Note: Descriptions are shown in the official language in which they were submitted.
1
THERMOSTAT WITH INTEGRATED SENSING SYSTEMS
15
[0001]
FIELD
[0002] This patent specification relates to system monitoring and
control, such
as the monitoring and control of heating, ventilation, and air conditioning
(HVAC)
systems. More particularly, this patent specification relates to a monitoring
and
control device, such as a thermostat, having integrated sensing systems.
BACKGROUND
[0003] Substantial effort and attention continues toward the development
of
newer and more sustainable energy supplies. The conservation of energy by
increased energy efficiency remains crucial to the world's energy future.
According
to an October 2010 report from the U.S. Department of Energy, heating and
cooling account for 56% of the energy use in a typical U.S. home, making it
the
largest energy expense for most homes. Along with improvements in the physical
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plant associated with home heating and cooling (e.g., improved insulation,
higher
efficiency furnaces), substantial increases in energy efficiency can be
achieved by
better control and regulation of home heating and cooling equipment. By
activating
heating, ventilation, and air conditioning (HVAC) equipment for judiciously
selected
time intervals and carefully chosen operating levels, substantial energy can
be
saved while at the same time keeping the living space suitably comfortable for
its
occupants.
[0004] It would be beneficial, at both a societal level and on a per-home
basis,
for a large number of homes to have their existing older thermostats replaced
by
newer, microprocessor controlled "intelligent" thermostats having more
advanced
HVAC control capabilities that can save energy while also keeping the
occupants
comfortable. To do this, these thermostats will need more information from the
occupants as well as the environments where the thermostats are located.
Sensors
in the home will gather real-time and historic data, such as occupancy data,
to be
used by thermostat to automate the HVAC controls. By analyzing this data,
thermostats will make decisions on heating, cooling and saving energy. For at
least
this reason, it is important to make sure sensors used by thermostats produce
accurate data. At the same time, however, there is a tension that can arise
between increasing the number and kinds of sensors on the thermostat, on the
one
hand, while also provisioning the thermostat with a reasonably compact and
visually pleasing form factor, on the other hand, for increasing the overall
appeal of
the intelligent thermostat to the purchasing public.
SUMMARY
[0005] .. Provided according to one or more embodiments is a thermostat having
a housing, the housing including a forward-facing surface, the thermostat
comprising a passive infrared (PIR) motion sensor disposed inside the housing
for
sensing occupancy in the vicinity of the thermostat. The PIR motion sensor has
a
radiation receiving surface and is able to detect the lateral movement of an
occupant in front of the forward-facing surface of the housing. The thermostat
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further comprises a grille member having one or more openings and included
along
the forward-facing surface of the housing, the grille member being placed over
the
radiation receiving surface of the PIR motion sensor. The grille member is
configured and dimensioned to visually conceal and protect the PIR motion
sensor
disposed inside the housing, the visual concealment promoting a visually
pleasing
quality of the thermostat, while at the same time permitting the PIR motion
sensor
to effectively detect the lateral movement of the occupant. In one embodiment,
the
grille member openings are slit-like openings oriented along a substantially
horizontal direction.
[0006] In one embodiment a temperature sensor is also positioned behind the
grille member, the temperature sensor also being visually concealed behind the
grille member. In one embodiment the grille member is formed from a thermally
conductive material such as a metal, and the temperature sensor is placed in
thermal communication with the metallic grille, such as by using a thermal
paste or
the like. Advantageously, in addition to exposing the temperature sensor to
ambient room air by virtue of the grille openings, the metallic grille member
can
further improve temperature sensing performance by acting as a sort of
"thermal
antenna" for the temperature sensor.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] FIG. 1 is a diagram illustrating an exemplary enclosure using a
thermostat implemented in accordance with aspects of the present invention for
controlling one or more environmental conditions;
[0008] FIG. 2 is a schematic diagram of an HVAC system controlled using a
thermostat designed in accordance with implementations of the present
invention;
[0009] FIGS. 3A-3B illustrate a grille member affixed to a forward-facing
surface of a thermostat designed in accordance with implementations of the
present invention;
[0010] FIGS. 4A-B illustrate a user's hand controlling a thermostat
designed in
accordance with implementations of the present invention;
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[0011] FIGS. 5A-5G illustrate a thermostat in various states of disassembly
and
the position of a grille member designed in accordance with the present
invention
in relationship to sensors and other components associated with the
thermostat;
[0012] FIG. 6 illustrates a perspective view of partially assembled head
unit
front from the thermostat showing the positioning of sensors in relation to
the grille
member designed in accordance with aspects of the present invention;
[0013] FIG. 7A-7B illustrates infrared sources interacting with the slit-
like
openings in a grille member designed in accordance with the present invention;
[0014] FIGS. 8A-8D illustrate altering the openings of a grille member
along a
vertical distance to change the sensitivity of a PIR motion sensor in
accordance
with aspects of the present invention;
[0015] FIG. 9 is flow chart diagram that outlines the operations associated
with
integrating sensor capabilities with a thermostat and grille member in
accordance
with aspects of the present invention;
[0016] FIGS. 10-17 are omitted from the instant patent specification;
[0017] FIGS. 18A-B illustrate front and perspective views, respectively, of
a
visually appealing thermostat having a user-friendly interface in accordance
with
aspects of the present invention;
[0018] FIG. 18C illustrates a cross-sectional view of the thermostat of
FIGS.
18A-18B;
[0019] FIGS. 19A-19B illustrate exploded front and rear perspective views,
respectively, of a head unit and a backplate of the thermostat of FIGS. 18A-
18C;
[0020] FIGS. 20A-20B illustrate exploded front and rear perspective views,
respectively, of the head unit of FIGS. 19A-19B;
[0021] FIGS. 21A-21B illustrate exploded front and rear perspective views,
respectively, of a frontal assembly of the head unit of FIGS. 20A-20B;
[0022] FIGS. 22A-22B illustrate exploded front and rear perspective views,
respectively, of the backplate of FIGS. 19A-19B;
[0023] FIG. 23 illustrates an exploded perspective upward view of the head
unit
of FIGS. 19A-19B;
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[0024] FIG. 24 illustrates a head-on view of a head unit circuit board of
the
head unit of FIGS. 19A-19B;
[0025] FIG. 25 illustrates a rear view of a backplate circuit board of
the
backplate of FIGS. 19A-19B;
[0026] FIGS. 26A-26C illustrate conceptual examples of a sleep-wake timing
dynamic between a relatively high-powered head unit microprocessor of a
thermostat and a relatively low-powered backplate microcontroller of the
thermostat
in accordance with aspects of the present invention;
[0027] FIG. 27 illustrates an overview diagram of the functional
software,
firmware, and/or programming architecture of a thermostat head unit
microprocessor in accordance with aspects of the present invention;
[0028] FIG. 28 illustrates an overview diagram of the functional
software,
firmware, and/or programming architecture of a thermostat backplate
microcontroller in accordance with aspects of the present invention; and
[0029] FIG. 29 illustrates a front view of wiring terminals of a thermostat
backplate in accordance with aspects of the present invention.
DETAILED DESCRIPTION
[0030] In the following detailed description, for purposes of
explanation,
numerous specific details are set forth to provide a thorough understanding of
the
various implementations of the present invention. Those of ordinary skill in
the art
will realize that these various implementations of the present invention are
illustrative only and are not intended to be limiting in any way. Other
implementations of the present invention will readily suggest themselves to
such
skilled persons having the benefit of this disclosure.
[0031] In addition, for clarity purposes, not all of the routine features
of the
implementations described herein are shown or described. One of ordinary skill
in
the art would readily appreciate that in the development of any such actual
implementation, numerous implementation-specific decisions may be required to
achieve specific design objectives. These design objectives will vary from one
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implementation to another and from one developer to another. Moreover, it will
be
appreciated that such a development effort might be complex and time-consuming
but would nevertheless be a routine engineering undertaking for those of
ordinary
skill in the art having the benefit of this disclosure.
[0032] It is to be appreciated that while one or more implementations are
described further herein in the context of typical HVAC system used in a
residential
home, such as single-family residential home, the scope of the present
teachings is
not so limited. More generally, thermostats according to one or more of the
preferred implementations are applicable for a wide variety of enclosures
having
one or more HVAC systems including, without limitation, duplexes, townhomes,
multi-unit apartment buildings, hotels, retail stores, office buildings and
industrial
buildings. Further, it is to be appreciated that while the terms user,
customer,
installer, homeowner, occupant, guest, tenant, landlord, repair person, and
the like
may be used to refer to the person or persons who are interacting with the
thermostat or other device or user interface in the context of one or more
scenarios
described herein, these references are by no means to be considered as
limiting
the scope of the present teachings with respect to the person or persons who
are
performing such actions.
[0033] The subject matter of this patent specification relates to the
subject
matter of the following commonly assigned applications
U.S. Ser. No. 12/881,430 filed September 14,
2010; U.S. Ser. No. 12/881,463 filed September 14, 2010; U.S. Prov. Ser. No.
61/415,771 filed November 19, 2010; U.S. Prov. Ser. No. 61/429,093 filed
December 31, 2010; U.S. Ser. No. 12/984,602 filed January 4, 2011; U.S. Ser.
No.
12/987,257 filed January 10, 2011; U.S. Ser. No. 13/033,573 filed February 23,
2011; U.S. Ser. No. 29/386,021, filed February 23, 2011; U.S. Ser. No.
13/034,666
filed February 24, 2011; U.S. Ser. No. 13/034,674 filed February 24, 2011;
U.S.
Ser. No. 13/034,678 filed February 24, 2011; U.S. Ser. No. 13/038,191 filed
March
1,2011; U.S. Ser. No. 13/038,206 filed March 1,2011; U.S. Ser. No. 29/399,609
filed August 16, 2011; U.S. Ser. No. 29/399,614 filed August 16, 2011; U.S.
Ser.
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No. 29/399,617 filed August 16, 2011; U.S. Ser. No. 29/399,618 filed August
16,
2011; U.S. Ser. No. 29/399,621 filed August 16, 2011; U.S. Ser. No. 29/399,623
filed August 16, 2011; U.S. Ser. No. 29/399,625 filed August 16, 2011; U.S.
Ser.
No. 29/399,627 filed August 16, 2011; U.S. Ser. No. 29/399,630 filed August
16,
2011; U.S. Ser. No. 29/399,632 filed August 16, 2011; U.S. Ser. No. 29/399,633
filed August 16, 2011; U.S. Ser. No. 29/399,636 filed August 16, 2011; U.S.
Ser.
No. 29/399,637 filed August 16, 2011; U.S. Ser. No. 13/199,108, filed August
17,
2011; U.S. Ser. No. 13/267,871 filed October 6, 2011; U.S. Ser. No. 13/267,877
filed October 6, 2011; U.S. Ser. No. 13/269,501, filed October 7, 2011; U.S.
Ser.
No. 29/404,096 filed October 14, 2011; U.S. Ser. No. 29/404,097 filed October
14,
2011; U.S. Ser. No. 29/404,098 filed October 14, 2011; U.S. Ser. No.
29/404,099
filed October 14, 2011; U.S. Ser. No. 29/404,101 filed October 14, 2011; U.S.
Ser.
No. 29/404,103 filed October 14, 2011; U.S. Ser. No. 29/404,104 filed October
14,
2011; U.S. Ser. No. 29/404,105 filed October 14, 2011; U.S. Ser. No.
13/275,307
filed October 17, 2011; U.S. Ser. No. 13/275,311 filed October 17, 2011; U.S.
Ser.
No. 13/317,423 filed October 17, 2011; U.S. Ser. No. 13/279,151 filed October
21,
2011; U.S. Ser. No. 13/317,557 filed October 21, 2011; and U.S. Prov. Ser. No.
61/627,996 filed October 21, 2011.
[0034] FIG. 1 is a diagram illustrating an exemplary enclosure using a
thermostat 110 implemented in accordance with the present invention for
controlling one or more environmental conditions. For example, enclosure 100
illustrates a single-family dwelling type of enclosure using thermostat 110
for the
control of heating and cooling provided by an HVAC system 120. Alternate
implementations of the present invention may be used with other types of
enclosures including a duplex, an apartment within an apartment building, a
light
commercial structure such as an office or retail store, or a structure or
enclosure
that is a combination of these and other types of enclosures.
[0035] Some implementations of thermostat 110 in FIG. 1 incorporate one
or
more sensors to gather data from the environment associated with enclosure
100.
Sensors incorporated in thermostat 110 may detect occupancy, temperature,
light
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and other environmental conditions and influence the control and operation of
HVAC system 120. Thermostat 110 uses a grille member (not shown in FIG. 1)
implemented in accordance with the present invention to cover the sensors. In
part,
the grille member of the present invention adds to the appeal and attraction
of the
thermostat 110 as the sensors in thermostat 110 do not protrude, or attract
attention from occupants of enclosure 100 and the thermostat 110 fits with
almost
any decor. Keeping sensors within thermostat 110 also reduces the likelihood
of
damage and loss of calibration during manufacture, delivery, installation or
use of
thermostat 110. Yet despite covering these sensors, the specialized design of
the
grille member facilitates accurately gathering occupancy, temperature and
other
data from the environment. Further details on this design and other aspects of
the
grille member are also described in detail later herein.
[0036] In some implementations, thermostat 110 may wirelessly communicate
with remote device 112 gathering information remotely from the user and from
the
environment detectable by the remote device 112. For example, the remote
device
112 can wirelessly communicate with the thermostat 110 providing user input
from
the remote location of remote device 112 or may be used to display information
to
a user, or both. Like thermostat 110, implementations of remote device 112 may
also include sensors to gather data related to occupancy, temperature, light
and
other environmental conditions. A grille member (not shown in FIG. 1) designed
in
accordance with the present invention may also be used to conceal these
sensors
maintaining an attractive and pleasing appearance of the remote device 112
within
the enclosure 100. In an alternate implementation, remote device 112 may also
be
located outside of the enclosure 100.
[0037] FIG. 2 is a schematic diagram of an HVAC system controlled using a
thermostat designed in accordance with implementations of the present
invention.
HVAC system 120 provides heating, cooling, ventilation, and/or air handling
for an
enclosure, such as a single-family home 100 depicted in FIG. 1. System 120
depicts a forced air type heating and cooling system, although according to
other
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implementations, other types of HVAC systems could be used such as radiant
heat
based systems, heat-pump based systems, and others.
[0038] In heating, heating coils or elements 242 within air handler 240
provide
a source of heat using electricity or gas via line 236. Cool air is drawn from
the
enclosure via return air duct 246 through filter 270, using fan 238 and is
heated
through heating coils or elements 242. The heated air flows back into the
enclosure at one or more locations via supply air duct system 252 and supply
air
registers such as register 250. In cooling, an outside compressor 230 passes a
gas
such as Freon through a set of heat exchanger coils 244 to cool the gas. The
gas
then goes through line 232 to the cooling coils 234 in the air handler 240
where it
expands, cools and cools the air being circulated via fan 238. A humidifier
254
may optionally be included in various implementations that returns moisture to
the
air before it passes through duct system 252. Although not shown in FIG. 2,
alternate implementations of HVAC system 120 may have other functionality such
as venting air to and from the outside, one or more dampers to control airflow
within the duct system 252 and an emergency heating unit. Overall operation of
HVAC system 120 is selectively actuated by control electronics 212
communicating
with thermostat 110 over control wires 248.
[0039] FIGS. 3A-3B illustrate a grille member incorporated in a
thermostat
designed in accordance with implementations of the present invention.
Thermostat
110 includes control circuitry and is electrically connected to an HVAC
system,
such as HVAC system 120 shown in FIG. 1 and FIG. 2. The design of a grille
member 324 compliments the sleek, simple, uncluttered and elegant design of
thermostat 110 while facilitating the integration and operation of sensors
located
within a housing 346 of the thermostat. In the implementation as illustrated,
thermostat 110 is enclosed by housing 346 with a forward-facing surface
including
a cover 314 and the grille member 324. Some implementations of housing 346
include a backplate 340 and a head unit 310. Housing 346 provides an
attractive
and durable configuration for one or more integrated sensors used by
thermostat
110 and contained therein. In some implementations, grille member 324 may be
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flush-mounted with the cover 314 on the forward-facing surface of housing 346.
Together grille member 324 as incorporated in housing 346 does not detract
from
home or commercial decor, and indeed can serve as a visually pleasing
centerpiece for the immediate location in which it is located.
[0040] A central display area 316 of cover 314 allows information related
to the
operation of the thermostat to be displayed while an outer area 326 of cover
314
may be made opaque using a paint or smoke finish. For example, central display
area 316 may be used to display a current temperature as illustrated in FIG.
3A
with the numerals, "75" indicating 75 degrees.
[0041] Grille member 324 is designed to conceal sensors from view promoting
a visually pleasing quality of the thermostat yet permitting them to receive
their
respective signals. Openings 318 in grille member 324 along the forward-facing
surface of the housing allow signals to pass through that would otherwise not
pass
through cover 314. For example, glass, polycarbonate or other similar
materials
used for cover 314 are capable of transmitting visible light but are highly
attenuating to infrared energy having longer wavelengths in the range of 10
microns, which is the radiation band of operation for many passive infrared
(PIR)
occupancy sensors. Notably, included in the thermostat according to some
preferred implementations is an ambient light sensor (not shown) and an active
proximity sensor (not shown) positioned near the top of the thermostat just
behind
the cover 314. Unlike PIR sensors, the ambient light sensor and active
proximity
sensor are configured to detect electromagnetic energy in the visible and
shorter-
infrared spectrum bands having wavelengths less than 1 micron, for which the
glass or polycarbonate materials of the cover 314 are not highly attenuating.
In
some implementations, grille member 324 includes openings 318 in accordance
with one or more implementations that allow the longer-wavelength infrared
radiation to pass through the openings towards a passive infrared (PIR) motion
sensor 330 as illustrated. Because grille member 324 is mounted over the
radiation
receiving surface of PIR motion sensor 330, PIR motion sensor 330 continues to
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receive the longer wavelength infrared radiation through the openings 318 and
detect occupancy in an enclosure.
[0042] Additional implementations of grille member 324 also facilitate
additional
sensors to detect other environmental conditions. In some implementations,
grille
member 324 helps a temperature sensor 334 situated inside of housing 346
measure the ambient temperature of air. Openings 318 in grille member 324
promote air flow towards temperature sensor 334 located below grille member
324
thus conveying outside temperatures to the interior of housing 346. In further
implementations, grille member 324 may be thermally coupled to temperature
sensor 334 promoting a transfer of heat from outside the housing 346. Details
on
the operation of grille member 324 with these and other sensors are described
in
further detail later herein.
[0043] Implementations of thermostat 110 are circular in shape and have
an
outer ring 312 for receiving user input. Side view of thermostat 110 in FIG.
3B
further highlights this curved spherical shape of cover 314 and grille member
324
gently arcing outward matching the corresponding surface portion of outer ring
312.
In some implementations, the curvature of cover 314 may tend to magnify
information displayed in central display area 316 thus making information
easier to
read by users. The shape of thermostat 110 not only provides a visually
appealing
accent when it is mounted on the wall but a natural shape for users to touch
and
adjust with their hands. Accordingly, the diameter of thermostat 110 may be
approximately 80mm or another diameter that readily fits the hand. In various
implementations, rotating outer ring 312 allows the user to make adjustments,
such
as selecting a new target temperature. For example, the target temperature may
be increased by rotating the outer ring 312 clockwise and decreased by
rotating the
outer ring 312 counter-clockwise.
[0044] Preferably, outer ring 312 is mechanically mounted in a manner
that
provides a smooth yet viscous feel to the user, for further promoting an
overall
feeling of elegance while also reducing spurious or unwanted rotational
inputs.
According to various implementations, outer ring 312 rotates on plastic
bearings
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and uses an optical digital encoder to measure the rotational movement and/or
rotational position of the outer ring 312. In accordance with alternate
implementations, other technologies such as mounting the outer ring 312 on a
central shaft may be employed.
[0045] .. In accordance with implementations of the present invention, vents
342
facilitate ventilation through gap 332 between the outer ring 312 and the body
of
head unit 310; through gap 344 between the head unit 310 and the backplate
340,
and into the backplate 340 via vents 342. Some of this air flow may also pass
through openings 318 and over sensors concealed by grille member 324. In
general, air circulation through gaps 332, 344, openings 318 and vents 342
serve
at least two purposes. Firstly, the air circulation allows the ambient air to
reach one
or more sensors located inside the thermostat. Secondly, the air circulation
allows
electronics in thermostat 110 to cool such that heat from the electronics does
not
significantly affect the sensing of the ambient air characteristics. Aside
from
openings 318, other entrance areas for air circulation such as gap 332, gap
344
and vents 342 are visually hidden from the user as shown in FIGs. 3A-3B, thus
allowing for a simple, visually uncluttered design that facilitates ease of
use by
users. Optional implementations of the present invention further include a
locking
mechanism that is engaged via turning the screw head 322 a quarter turn.
[0046] FIGS. 4A-B illustrate a user's hand controlling a thermostat
designed in
accordance with implementations of the present invention. As illustrated,
thermostat 110 is wall-mounted, circular in shape and has a rotatable outer
ring
312 for receiving user input. Cover 314 on thermostat 110 includes central
display
area 316 for providing information and feedback to the user before, during and
after operating thermostat 110. In some implementations, outer area 326 of
cover
314 delineates an area for the user to push or otherwise manipulate thermostat
110 and thus is made opaque with paint or smoke finish. In accordance with the
present invention, grille member 324 provides an additional area that the user
may
rest their hand while viewing or operating thermostat 110. It can be
appreciated
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that grille member 324 protects sensors from the user's hand yet allows the
sensors to receive signals and gather information on the environment.
[0047] Head unit 310 of thermostat 110 slides on to backplate (not shown)
and
further includes head unit front 402 and head unit frame 404. The head unit
front
402 includes outer ring 312, central display area 316 and outer area 326 of
cover
314 and grille member 324 designed in accordance with implementations of the
present invention. A portion of the electronics and sensors (not shown) in
thermostat 110 are also included within head unit front 402.
[0048] According to some implementations, for the combined purposes of
inspiring user confidence and further promoting visual and functional
elegance, the
thermostat 110 is controlled by only two types of user input, the first being
a
rotation of the outer ring 312 as illustrated in FIG. 4A (also referred to as
a "rotate
ring"), and the second being an inward push on the head unit front 402 until
an
audible and/or tactile "click" occurs as illustrated in FIG. 4B. According to
some
implementations, the inward push illustrated in FIG. 4B only causes the outer
ring
312 to move forward, while in other implementations the entire head unit front
402
moves inwardly together when pushed. In some implementations, cover 314 and
grille member 324 do not rotate with outer ring 312.
[0049] According to some implementations, multiple types of user input
may be
generated depending on the way a pushing inward of head unit front 402 is
effectuated. In some implementations a single brief push inward of head unit
front
402 until the audible and/or tactile click occurs followed by a release
(single click)
can be interpreted as one type of user input (also referred to as an "inward
click").
In other implementations, pushing the head unit front 402 in and holding with
an
the inward pressure for an amount of time such as 1-3 seconds can be
interpreted
as another type of user input (also referred to as a "press and hold").
According to
some further implementations, other types of user input can be effectuated by
a
user such as double and/or multiple clicks, and pressing and holding for
longer
and/or shorter periods of time. According to other implementations, speed-
sensitive or acceleration-sensitive rotational inputs may also be implemented
to
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create further types of user inputs (e.g., a very large and fast leftward
rotation
specifies an "Away" occupancy state, while a very large and fast rightward
rotation
specifies an "Occupied" occupancy state).
[0050] FIGS. 5A-5G illustrate a thermostat in various states of
disassembly and
the position of grille member 324 designed in accordance with the present
invention as it relates to sensors and other components. The disassembled view
of
thermostat 110 in FIG. 5A illustrates head unit 310 slidably removed from
backplate 340. In this configuration, it can be appreciated that backplate 340
can
function as a wall dock to the balance of the thermostat 110 contained in head
unit
310 thereby contributing to ease of installation, configuration and upgrading,
according to some implementations. For example, in such implementations a new,
upgraded or refurbished head unit 310 may be placed over an existing backplate
340 without requiring rewiring or remounting of thermostat 110 on the wall.
[0051] As previously illustrated and described, thermostat 110 is wall
mounted
having a circular shape and rotatable ring 312 for receiving user input.
Thermostat
110 has a cover 314 that includes a central display area 316 and outer area
326.
Head unit 310 portion of thermostat 110 slides onto and is affixed to back
plate
340. According to some implementations the connection of the head unit 310 to
backplate 340 can be accomplished using magnets, bayonet, latches and catches,
tabs or ribs with matching indentations, or simply friction on mating portions
of the
head unit 310 and backplate 340.
[0052] According to some implementations, a locking mechanism is
optionally
provided wherein a post 502 on the backplate 340 is engaged by a quarter turn
of a
latch using a flat head screw head or other type of screw heads connected with
the
latch. For example, a less common type of screw head such as a hex or torx may
be used to provide greater security and deter removal of head unit 310 when
thermostat 110 is installed in public locations. According to some
implementations,
the head unit 310 includes a processing system 504, display driver 508 and a
wireless communications system 510. The processing system 504 is adapted to
cause the display driver 508 and central display area 316 to display
information to
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the user, and to receiver user input via the rotating ring 312. The processing
system 504, according to some implementations, is capable of maintaining and
updating a thermodynamic model for the enclosure in which the HVAC system is
installed. For further detail on the thermodynamic modeling, see U.S. Patent
Ser.
No. 12/881,463 filed September 14, 2010.
According to some implementations, the wireless communications system
510 is used to communicate with a combination of devices such as personal
computers, other thermostats or remote devices and/or HVAC system components.
[0053] .. Electronics 512 and temperature sensor 514 are ventilated via vents
342 in backplate 340. A bubble level 516 is provided to aid in correctly
orienting
the thermostat 110 when it is mounting on a wall. Wire connectors 518 are
provided to allow for connection to HVAC system wires. Connection terminal 520
provides electrical connections between the head unit 310 and backplate 340.
[0054] FIGS. 5B-C illustrate a top and bottom view of a thermostat
backplate in
accordance with implementations of the present invention. The backplate 340 is
mounted on a wall using screws through two openings: round hole 522 and
slotted
hole 524. By using a slotted hole 524, the user or installer can make small
adjustments in the angle of mounting of backplate 340. As shown in FIG. 5B,
backplate 340 includes bubble level 516 including a window 526 through which
the
user can check and make a level mounting of backplate 340 on a wall. The HVAC
system wires pass through a large rectangular opening 528 and are connected to
wire connectors 518. According to some implementations, eight wire connectors
are provided as shown in FIG. 5B, and labeled with common HVAC system wire
names.
[0055] FIG. 5C illustrates the backside of backplate 340 facing the wall
when
thermostat 110 is wall mounted. In one implementation, a temperature sensor
514
(which, generally speaking, can be of coarser precision in comparison to the
head
unit temperature sensor 334, although the scope of the present teachings is
not so
limited) included in backplate 340 which allows the backplate 340 to operate
as a
functioning thermostat even when the head unit 310 has been removed. For
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example, the electronics 512 in backplate 340 includes a microcontroller (MCU)
processor, and driver circuitry for opening and closing the HVAC control
circuits.
For example, these control circuits can be used for turning on and turning off
the
one or more HVAC functions such as heating and cooling. The electronics 512
also includes flash memory which is used to store the series of programmed
settings that take effect at different times of the day. For example, a
default set of
programmed set point changes in flash memory may be carried out even when the
head unit 310 in FIG. 5A is not attached to the backplate 340. According to
some
implementations, the electronics 512 also includes power harvesting circuitry
so as
to obtain power from the HVAC control circuit(s) even when an HVAC common
power wire is not available.
[0056] FIGS. 5D-5E illustrates a perspective view of the head unit 310
portion
of the thermostat 110 assembled as a single component and disassembled into
multiple subcomponents. In the assembled single component illustrated in FIG.
5D,
head unit 310 includes a head unit front 402 and head unit frame 404. Head
unit
310 in FIG. 5D is conveniently designed to be separated from backplate (not
shown) and facilitates easy repair, replacement or upgrades to the
electronics,
firmware and software in the head unit 310. For example, the thermostat may be
upgraded by removing head unit 310 from the backplate and replacing with an
upgraded or new head unit 310.
[0057] As illustrated in FIG. 5E, head unit front 402 may further be
disassembled into grille member 324, cover 314, head unit frontal assembly 530
and outer ring 312. Head unit frontal assembly 530 is slidably mounted and
secured to head unit frame 404 urging outer ring 312 to be held between the
head
unit frontal assembly 530 and head unit frame 404. In some implementations,
outer
ring 312 is rotatable and receives user inputs through clockwise or
counterclockwise rotations while head unit frontal assembly 530 remains fixed
in
position.
[0058] Cover 314 fits over and protects display module 532, which is used
to
display information to a user viewing the thermostat. As an example,
information
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displayed by display module 532 may include a current temperature such as a
temperature of 75 degrees displayed by display module 532 in the central
display
area 316 in FIG. 3A. In other implementations, display module 532 may also
display a variety of other information to the user including setpoints,
configuration
information, diagnostics and thermostat programming details. Display module
532
in accordance with some implementations is a dot-matrix layout (individually
addressable) such that arbitrary shapes can be generated, rather than being a
segmented layout. According to other implementations, a combination of dot-
matrix
layout and a segmented layout may also be employed by display module 532.
[0059] Display module 532 may be implemented in accordance with the
present invention using a back-lit color liquid crystal display (LCD).
According to
other implementations, display module 532 may use display technologies such as
passive and/or monochrome LCD, organic light-emitting diode (OLED), or
electronic ink (e-ink) display technology. F-ink is a particularly well suited
display
technology for some implementations as it continues to reflect light while not
drawing power and energy. Additionally, E-ink display technology implemented
in
accordance with the present invention also conserves energy as it does not
require
a particularly short refresh time.
[0060] Grille member 324 may be used to conceal and protect a number of
different sensors in accordance with the present invention. In some
implementations, these sensors may include a temperature sensor 334 and PIR
motion sensor 330 sensor integrated with the thermostat. In the implementation
illustrated in FIG. 5E, PIR motion sensor 330 includes a Fresnel lens 534 to
help
direct infrared radiation onto the infrared sensitive elements (not shown in
FIG. 5E)
of the PIR motion sensor 330. Grille member 324 acts as a cover yet passes a
substantial amount of infrared radiation through Fresnel lens 534 and onto the
infrared sensitive elements. As will be described in detail later herein, the
design of
grille member 324 allows PIR motion sensor 330 to detect occupants movement
across a wide range of angles in the vicinity of the thermostat even when
covered
by grille member 324.
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[0061] Likewise, grille member 324 may also conceal temperature sensor
334
situated near the bottom of edge of Fresnel lens 534 as indicated in FIG. 5E.
The
grille member 324 helps protect the temperature sensor 334 from being damaged
and contributes to the overall streamlined appeal of the thermostat.
Additionally,
constructing grille member 324 from a heat conducting material, such as metal
or a
metallic alloy, helps absorb the ambient heat in the vicinity of the
thermostat and
deliver to temperature sensor 334 for a more accurate measurement.
[0062] FIGS. 5F-5G illustrates a perspective view of the head unit
frontal
assembly 530 appearing as one assembled component and disassembled into
multiple subcomponents. In some implementations, head unit frontal assembly
530
includes at least three subcomponents: a display module 532, a head unit front
plate 536 and head unit circuit board 538. Display module 532 serves to
display
information to a user and may be separated from head unit front plate 536 as
illustrated.
[0063] In accordance with some implementations, head unit front plate 536
is
disposed to receive temperature sensor 334 in a temperature sensor slot 540.
The
temperature sensor 334 is affixed to, and extends approximately normal to the
planar surface of head unit circuit board 538. In contrast, PIR motion sensor
330 is
coplanar with the surface of head unit circuit board 538 and thus also normal
to the
temperature sensor 334. When head unit circuit board 538 is slidably mounted
to
the backside of head unit front plate 536, temperature sensor 334 is urged
along
the normal to head unit circuit board 538 and inserted into temperature sensor
slot
540. Likewise, slidably mounting head unit circuit board 538 into the backside
of
head unit front plate 536 situates the infrared sensitive elements 331 behind
Fresnel lens 534 and making up PIR motion sensor 330 as previously illustrated
in
FIG. 5E and FIG. 3A.
[0064] Perspective view of partially assembled head unit front 402 in
FIG. 6
shows the positioning of grille member 324 designed in accordance with aspects
of
the present invention with respect to several sensors used by the thermostat.
In
some implementations, head unit front 402 as illustrated in FIG. 6 includes
the
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outer ring 312, grille member 324 positioned on head unit front assembly 530
with
cover 314 removed as illustrated. Head unit front 402 makes up a portion of
head
unit 310 and housing 346 illustrated in FIG. 3B, which is used to enclose the
thermostat.
[0065] .. In some implementations, grille member 324 covers one or more
sensors used by the thermostat and is attached to a forward-facing surface of
the
housing by way of the head unit front assembly 530. The design and position of
grille member 324 creates a smooth, sleek and visually pleasing impression to
users while also serving to improve the durability and function of the one or
more
sensors it conceals. In some implementations, benefits from grille member 324
may be attributed to a shape of openings 318, the materials used to make
grille
member 324 or a positioning of grille member 324 with respect to one or more
sensors, as well as combinations thereof.
[0066] In some implementations, placement of grille member 324 over PIR
motion sensor 334 as illustrated in FIG. 6 conceals and protects the sensor.
For
example, grille member 324 may protect PIR motion sensor 334 during
manufacture, shipping, installation or use from a user's hands operating the
thermostat as illustrated in FIG. 4A and 4B. Concealment not only protects the
PIR
motion sensor 334 but also promotes visually pleasing thermostat suitable for
use
in a variety of residential and commercial applications.
[0067] .. In accordance with implementations of the present invention, one or
more openings 318 in the grille member 324 design allow the PIR motion sensor
334, despite being concealed, to detect the lateral motion of occupants in a
room
or area. Positioning PIR motion sensor 334 along the forward-facing surface of
head unit front assembly 530 allows the sensor's radiation receiving elements
to
continue to detect the infrared radiation emitted by these occupants in the
vicinity
of the thermostat. As described in further detail later herein, PIR motion
sensor 334
may detect occupants moving laterally due to the shape of openings 318, which
are slit-like and elongated along a substantially horizontal direction. In
some
implementations, the Fresnel lens 534 helps focus the radiation from these
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occupants onto the infrared sensitive sensor elements (not shown in FIG. 6) of
the
PIR motion sensor 334. For example, the grille member 324 has one or more
openings placed over the radiation receiving elements and Fresnel lens 534 of
the
PIR motion sensor 334. While grille member 324 may be constructed from a
variety
of materials including metal, plastic, glass, carbon-composite, and metallic
alloy, it
is generally preferable for purposes of increased temperature sensing
precision for
the grille member to be made of a material with a high thermal conductivity,
such
as a metal or metallic alloy.
[0068] Grille member 324 may also enhance the operation of sensors in the
thermostat. In some implementations, temperature sensor 334 is not only
protected
but the detection of ambient temperatures is enhanced by placement of grille
member 324. For example, where grille member 324 is made from a thermally
conductive material such as a metal or metallic alloy, it operates as a
"thermal
antenna" and absorbs ambient temperature from a broader area than temperature
sensor 334 could otherwise sample. Temperature sensor 334 positioned
substantially normal to head unit circuit board 538 towards grille member 324
may
be close enough to receive heat absorbed by grille member 324.
[0069] In some implementations, applying a thermally conductive materials
542, such as a paste, thermal adhesive or thermal grease between temperature
sensor 334 and inward facing surface of grille member 324 improves the thermal
conductivity between these two components and the accuracy of the temperature
measurement. Thermally coupling grille member 324 with temperature sensor 334
assists temperature sensor 334 to measure the ambient air temperature outside
rather than inside of the housing holding the thermostat.
[0070] Some implementations of temperature sensor 330 may use a pair of
thermal sensors to more accurately measure ambient temperature. A first or
upper
thermal sensor 330a associated with temperature sensor 330 tends to gather
temperature data closer to the area outside or on the exterior of the
thermostat
while a second or lower thermal sensor 330b tends to collect temperature data
more closely associated with the interior of the housing. In one
implementation,
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each of the temperature sensors 330a and 330b comprises a Texas Instruments
TMP112 digital temperature sensor chip. To more accurately determine the
ambient temperature, the temperature taken from the lower thermal sensor 330b
is
taken into consideration in view of the temperatures measured by the upper
thermal sensor 330a and when determining the effective ambient temperature.
This configuration can advantageously be used to compensate for the effects of
internal heat produced in the thermostat by the microprocessor(s) and/or other
electronic components therein, thereby obviating or minimizing temperature
measurement errors that might otherwise be suffered. In some implementations,
the accuracy of the ambient temperature measurement may be further enhanced
by thermally coupling upper thermal sensor 330a of temperature sensor 330 to
grille member 324 as the upper thermal sensor 330a better reflects the ambient
temperature than lower thermal sensor 331b. Details on using a pair of thermal
sensors to determine an effective ambient temperature is disclosed in United
States Patent No. 4,741,476 issued May 3, 1988 entitled, "Digital Electronic
Thermostat With Correction for Triac Self Heating", by Russo et al.
[0071] With exemplary reference to FIGS. 5F-5G and FIG. 6, the mutual
positioning and configuration of the grille member 324, Fresnel lens 534, PIR
sensor 330, upper thermal sensor 330a, and lower thermal sensor 330b provides
for an advantageous and synergistic combination of physical compactness and
visual sensor concealment, along with promoting ambient temperature sensor
accuracy and preserving PIR occupancy sensing functionality. In some ways this
can be seen as one beneficial outcome of a "dual use' of a key volume of space
lying between the Fresnel lens 534 and the surface of the PIR sensor 334,
wherein
the necessary spacing between the Fresnel lens 534 and the surface of the PIR
sensor 334 also serves as the space across which a temperature gradient
between
the lower thermal sensor 330b and upper thermal sensor 330a is formed and
sensed, this temperature gradient being leveraged to provide better ambient
temperature sensing than would be provided by a single-point thermal sensor.
In
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turn, the compactness promoted by the configuration of elements
534/334/330a/330b allows them to be placed behind the grille 324 without the
necessity of substantially enlarging the outward protrusion of the overall
housing.
At the same time, for preferred implementations in which the grille member 324
is
metallic and thermally coupled to the upper thermal sensor 330a, the high
thermal
conductivity of the grille member 324 still further enhances the accuracy of
temperature measurement by acting as a "thermal antenna," which is in addition
to
its other functions of concealment and ambient air access.
[0072] FIG. 7A-7B illustrates in detail how infrared sources interact
with slit-like
openings in a grille member designed in accordance with the present invention.
To
highlight the interactions, FIG. 7A illustrates grille member 324 with
openings 318
and PIR motion sensor 330 positioned behind grille member 324 as it would be
in a
thermostat designed in accordance with the present invention. In accordance
with
some implementations, openings 318 are slit-like along a substantially
horizontal
direction as illustrated. Infrared sources may sweep across a continuous wide
range of angles such as by the lateral movement an occupant walking across a
room or other area. To represented this range, FIG. 7A has arrows representing
a
left infrared source 702, a center infrared source 706 and a right infrared
source
704. For example, an occupant walking across a room in front of a thermostat
with
grille member 324 may first emit radiation appearing as a left infrared source
702
then gradually a center infrared source 706 and then gradually a right
infrared
source 704.
[0073] As FIG. 7A shows schematically, the slit-like openings 318 of
grille
member 324 allow a wide range of infrared sources to pass through towards PIR
motion sensor 330. Both left infrared source 702 and right infrared source 704
may
pass along the elongated horizontal openings 318 as indicated by the arrows of
these sources. Center infrared source 706 also passes through openings 318 in
grille member 324 as allowed by the vertical height of one or more of the
elongated
slits. It therefore can also be appreciated that the openings 318 from grille
member
324 having a slit-like shape allow the PIR motion sensor 330 to detect the
radiation
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emitted by an occupant moving laterally across a wide-range of angles near the
thermostat. For example, grille member 324 can detect an occupant moving on
the
left side of grille member 324 as a left infrared source 702 or on the right
side of
grille member 324 as a right infrared source 704. A person moving
approximately
in the center of grille member 324 would appear as a center infrared source
706
and also pass through openings 318 towards PIR motion sensor 330. Indeed,
grille
member 324 would also pass many other infrared sources at angles between left
infrared source 702, center infrared source 706 and right infrared source 704
through openings 318 towards PIR motion sensor 330.
[0074] FIG. 7B illustrates the effect of an occupant moving past a PIR
motion
sensor in a thermostat covered by a grille member of the present invention.
The
PIR motion sensor (not shown in FIG. 7B) sits behind grille member 324 much
like
PIR motion sensor 330 in FIG. 7A. The PIR motion sensor is capable of
detecting a
lateral change of radiation 710 caused by a laterally moving source of
infrared
radiation such as a person walking in a room. To make the occupancy detector
work properly, these lateral changes in radiation 710 caused by the occupant
must
be distinguished from overall changes in the infrared radiation caused by
sunlight
and ambient heat sometimes referred to as the common-mode signal.
[0075] In some implementations, the PIR motion sensor has a pair of
differential sensing elements setup with opposing polarity to reject the
common-
mode signal produced by radiation 710. When occupant 708 is not present or not
moving, sudden overall changes in radiation 710 caused by sunlight, heat or
vibration produce complimentary signals from the pair of differential sensing
elements simultaneously. The complimentary signals from the pair of
differential
sensing elements immediately cancel out these false-positive or common-mode
signals.
[0076] In comparison, an occupant 708 moving laterally in the direction
of the
arrows in FIG. 7B across a room or other space near thermostat 110 creates a
local change in radiation 710. The local change in radiation 710 is detected
and not
canceled out with the common-mode signal portion of radiation 710 as the
sensing
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elements are arranged along a horizontal axis and triggered sequentially, not
simultaneously, by the lateral movement,. Because openings 318 in grille
member
324 are slit-like, radiation 710 enters thermostat 110 and is detected by PIR
motion
sensor whether the occupant 708 is moving laterally from the far right, far
left or
laterally near the center area near the thermostat.
[0077] FIGS. 8A-8D illustrate altering the openings of a grille member
along a
vertical distance to change the sensitivity of a PIR motion sensor in
accordance
with aspects of the present invention. Generally, the PIR motion sensor's
sensitivity
to the height of occupants can be changed by varying the vertical span of the
openings in a grille member. In accordance with some implementations, a grille
member 802 illustrated in FIG. 8A is located on a forward-facing surface of
the
thermostat 810 mounted on a wall. Thermostat 810 is partially shown in FIG. 8B
for
convenience yet is similar to thermostat 110 described and illustrated in FIG.
3A.
Grille member 802 in FIG. 8A has several rows of openings 806, each having a
slit-
like shape and organized along a vertical span 804. Accordingly, a PIR motion
sensor (not shown in FIGS. 8A-80) behind grille member 802 used with
thermostat
810 in FIG. 8B and has an angle of sensitivity 808 or . If an occupant's
height is
within the angle of sensitivity 808 then the PIR motion sensor in thermostat
810 in
FIG. 8B should be able to detect the radiation emitted from the occupant's
lateral
movement. Conversely, an occupant whose height falls below the angle of
sensitivity 808, is not likely to be detected by the PIR motion sensor in
thermostat
810 in FIG. 8B.
[0078] In accordance with an alternate implementation, sensitivity to
height
may be decreased as illustrated in FIG. 8C by reducing the number of rows or
openings across the vertical span. Compared with grille member 802, the number
of rows of openings 816 in grille member 812 illustrated in FIG. 8C are fewer
in
number than the rows of openings 806. Moreover, openings 816 in grille member
812 are spread over a vertical span 814 that is both narrower and positioned
higher
than vertical span 804 in grille member 802. Consequently, using grille member
812 in thermostat 810 in FIG. 80 results in a narrower angle of sensitivity
818 or
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compared with the angle of sensitivity 808 or previously described. For
example,
a PIR motion sensor behind grille member 812 on thermostat 810 in FIG. 8D will
not detect occupants whose height is outside the angle of sensitivity 818 or .
As a
result, the same occupants detected by thermostat 810 with grille member 802
might not be tall enough to be detected by thermostat 810 using grille member
812.
Depending on the installation, it may be more desirable to use a grille member
more like grille member 812 in order to limit detection of occupants that are
taller in
height. To detect occupants that may be shorter in height, use of grille
member 802
in thermostat 810 may be more desirable.
[0079] Since FIGS. 8A-8D are meant to be illustrative, the shape, number,
size,
organization and location of openings in grille member 802 and 812 are but
exemplary and used for comparison purposes. Indeed, the designs of grille
members of the present invention should not be limited by specific sizes,
number of
openings, specific shapes or the absolute or relative positions of these or
other
features.
[0080] In some implementations, different grille members may be
manufactured
with a different number of openings having slit-like dimensions arranged in
one or
more rows. For example, a person installing thermostat 810 may select and
install
different grille members depending on the desired sensitivity to the heights
of the
occupants and the location of the thermostat 810 on a wall or other location.
In
other implementations, the installer may use a mask member attached to the
back
openings in the grille member to modify the openings and adjust the
sensitivity to
height. Instead of manufacturing different grille members, one grille member
can be
altered using the mask member to cover or uncover the desired number of
openings in the grille member. For example, the mask member may be plastic or
metal fittings with slit-like dimensions applied to the backside of grille
member 802
that fill one or more of openings 806. These fittings of the mask member may
be
finished in the same tone or color as the surface of grille member 802 in
order to
blend into the overall appearance of the grille member 802. Accordingly, the
sensitivity to the height of occupants may be varied depending on the coverage
by
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the mask member of the substantially horizontal slit-like openings used to
pass the
emitted radiation to the receiving surface of the PIR motion sensor.
[0081] Referring to FIG. 9, a flow chart diagram outlines the operations
associated with integrating sensor capabilities with a thermostat and grille
member
in accordance with aspects of the present invention. In some implementations,
the
integration operations include providing a housing for the thermostat designed
to
provide an attractive and durable configuration for one or more integrated
sensors
(902). Housing for the thermostat may be housing 346 and thermostat 110
illustrated in FIG. 3B as previously described. The thermostat is enclosed by
the
housing with a forward-facing surface for a cover and grille member in
accordance
with aspects of the present invention. The one or more integrated sensors
protected by the housing may include an occupancy sensor such as a PIR motion
detector, a temperature sensor, a humidity sensor, a proximity sensor or other
sensors that might be useful in operating a thermostat. Placing these and
other
sensors inside the housing protects them from being accidentally jarred or
broken
during manufacture, shipping, installation or use. Because sensors are
protected
inside the housing, they are more likely to retain their calibration and
provide
accurate measurement results for the thermostat.
[0082] Additionally, the integration operations may also provide a
passive
infrared (PIR) motion sensor disposed inside the housing and used to sense
occupancy in the vicinity of the thermostat (904). In some implementations,
the PIR
motion sensor has a radiation receiving surface able to detect the radiation
emitted
towards the forward-facing surface of the housing by the lateral movement of a
nearby occupant. Occupancy information detected by the PIR motion sensor may
be used by the thermostat to better adjust heating or cooling operations of an
HVAC in an enclosure such as a residential house. In some implementations, a
thermostat may use the occupancy information to turn the HVAC on when
occupancy is detected and off when no occupancy is detected by the PIR motion
sensor. In alternate implementations, the thermostat may use the occupancy
information generated by the PIR motion sensor as part of a heuristic that
learns
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when an enclosure is likely to be occupied or unoccupied and anticipates the
heating or cooling requirements. This heuristic may use real-time and historic
geographic weather trends and other factors combined with learned occupancy
patterns to determine when the enclosure needs cooling or heating. A
temperature
sensor disposed inside the housing may also be provided to detect the ambient
temperature in the vicinity of the thermostat. The PIR motion sensor and
temperature sensor may be similar to PIR motion sensor 330 and temperature
sensor 334 respectively illustrated in FIG. 6 as previously described.
[0083] Integration operations in accordance with the present invention
may
further attach a grille member along a forward-facing surface of the housing
and
placed over the radiation receiving surface of the PIR motion sensor (906). As
previously described, the grille member may substantially conceal and protects
the
PIR motion sensor disposed inside the housing. Concealing the PIR motion
sensor
promotes a visually pleasing quality of the thermostat as well as protects the
PIR
motion sensor during manufacture, shipment, installation and use. In some
implementations, the grille member may be similar to grille member 324
previously
described and illustrated in accordance with FIG. 3A. Accordingly, the grille
member may be manufactured from one or more materials selected from a set of
materials including: metal, plastic, glass, carbon-composite, metallic-carbon
composite and metallic alloy. The grille member may be a thermally conductive
material such as a metal or metal alloy and may be thermally coupled to the
temperature sensor also disposed inside the housing of the thermostat. In some
implementations, thermally coupling the temperature sensor to the grille
member
assists with the temperature sensors ability to measure an ambient temperature
of
air measured outside of the housing rather than inside of the housing.
[0084] FIGS. 18A-B illustrate a visually pleasing thermostat 1800 having
a
user-friendly interface, according to some embodiments. The thermostat 1800 of
FIGS. 18A-18B is generally similar to the thermostat 110 of FIGS. 3A-3B,
supra,
with additional and/or alternative aspects thereof being described
hereinbelow.
The term "thermostat" is used hereinbelow to represent a particular type of
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Versatile Sensing and Control Unit (VSCU) that is described in the commonly
assigned U.S. Prov. Ser. No. 61/429,093, supra, that is particularly
applicable for
HVAC control in an enclosure. Although "thermostat" and "VSCU unit" may be
seen as generally interchangeable for the contexts of HVAC control of an
enclosure, it is within the scope of the present teachings for each of the
embodiments hereinabove and hereinbelow to be applied to such VSCU units
having control functionality over measurable characteristics other than
temperature
(e.g., pressure, flow rate, height, position, velocity, acceleration,
capacity, power,
loudness, brightness) for any of a variety of different control systems
involving the
governance of one or more measurable characteristics of one or more physical
systems, and/or the governance of other energy or resource consuming systems
such as water usage systems, air usage systems, systems involving the usage of
other natural resources, and systems involving the usage of various other
forms of
energy. Unlike many prior art thermostats, thermostat 1800 preferably has a
sleek,
simple, uncluttered and elegant design that does not detract from home
decoration,
and indeed can serve as a visually pleasing centerpiece for the immediate
location
in which it is installed. Moreover, user interaction with thermostat 1800 is
facilitated
and greatly enhanced over known conventional thermostats by the design of
thermostat 1800. The thermostat 1800 includes control circuitry and is
electrically
connected to an HVAC system, such as is shown with thermostat 110 in FIGS. 1
and 2, supra. Thermostat 1800 is wall mounted, is circular in shape, and has
an
outer rotatable ring 1812 for receiving user input. Thermostat 1800 is
circular in
shape in that it appears as a generally disk-like circular object when mounted
on
the wall. Thermostat 1800 has a large front face lying inside the outer ring
1812.
According to some embodiments, thermostat 1800 is approximately 80 mm in
diameter. The outer rotatable ring 1812 allows the user to make adjustments,
such
as selecting a new target temperature. For example, by rotating the outer ring
1812 clockwise, the target temperature can be increased, and by rotating the
outer
ring 1812 counter-clockwise, the target temperature can be decreased. The
front
face of the thermostat 1800 comprises a clear cover 1814 that according to
some
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embodiments is polycarbonate, and a metallic portion 1824 preferably having a
number of slots formed therein as shown. According to some embodiments, the
surface of cover 1814 and metallic portion 1824 form a common outward arc or
spherical shape gently arcing outward, and this gentle arcing shape is
continued by
the outer ring 1812.
[0085] Although being formed from a single lens-like piece of material
such as
polycarbonate, the cover 1814 has two different regions or portions including
an
outer portion 18140 and a central portion 1814i. According to some
embodiments,
the cover 1814 is painted or smoked around the outer portion 18140, but leaves
the central portion 1814i visibly clear so as to facilitate viewing of an
electronic
display 1816 disposed thereunderneath. According to some embodiments, the
curved cover 1814 acts as a lens that tends to magnify the information being
displayed in electronic display 1816 to users. According to some embodiments
the
central electronic display 1816 is a dot-matrix layout (individually
addressable)
such that arbitrary shapes can be generated, rather than being a segmented
layout. According to some embodiments, a combination of dot-matrix layout and
segmented layout is employed. According to some embodiments, central display
1816 is a backlit color liquid crystal display (LCD). An example of
information
displayed on the electronic display 1816 is illustrated in FIG. 18A, and
includes
central numerals 1820 that are representative of a current setpoint
temperature.
According to some embodiments, metallic portion 1824 has number of slot-like
openings so as to facilitate the use of a passive infrared motion sensor 1830
mounted therebeneath. The metallic portion 1824 can alternatively be termed a
metallic front grille portion. Further description of the metallic
portion/front grille
portion is provided in the commonly assigned U.S. Ser. No. 13/199,108, supra.
The thermostat 1800 is preferably constructed such that the electronic display
1816
is at a fixed orientation and does not rotate with the outer ring 1812, so
that the
electronic display 1816 remains easily read by the user. For some embodiments,
the cover 1814 and metallic portion 1824 also remain at a fixed orientation
and do
not rotate with the outer ring 1812. According to one embodiment in which the
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diameter of the thermostat 1800 is about 80 mm, the diameter of the electronic
display 1816 is about 45 mm. According to some embodiments an LED indicator
1880 is positioned beneath portion 1824 to act as a low-power-consuming
indicator
of certain status conditions. For, example the LED indicator 1880 can be used
to
display blinking red when a rechargeable battery of the thermostat (see FIG.
4A,
infra) is very low and is being recharged. More generally, the LED indicator
1880
can be used for communicating one or more status codes or error codes by
virtue
of red color, green color, various combinations of red and green, various
different
blinking rates, and so forth, which can be useful for troubleshooting
purposes.
[0086] Motion sensing as well as other techniques can be use used in the
detection and/or predict of occupancy, as is described further in the commonly
assigned U.S. Ser. No. 12/881,430, supra. According to some embodiments,
occupancy information is used in generating an effective and efficient
scheduled
program. Preferably, an active proximity sensor 1870A is provided to detect an
approaching user by infrared light reflection, and an ambient light sensor
1870B is
provided to sense visible light. The proximity sensor 1870A can be used to
detect
proximity in the range of about one meter so that the thermostat 1800 can
initiate
"waking up" when the user is approaching the thermostat and prior to the user
touching the thermostat. Such use of proximity sensing is useful for enhancing
the
user experience by being "ready" for interaction as soon as, or very soon
after the
user is ready to interact with the thermostat. Further, the wake-up-on-
proximity
functionality also allows for energy savings within the thermostat by
"sleeping"
when no user interaction is taking place our about to take place. The ambient
light
sensor 1870B can be used for a variety of intelligence-gathering purposes,
such as
for facilitating confirmation of occupancy when sharp rising or falling edges
are
detected (because it is likely that there are occupants who are turning the
lights on
and off), and such as for detecting long term (e.g., 24-hour) patterns of
ambient
light intensity for confirming and/or automatically establishing the time of
day.
[0087] According to some embodiments, for the combined purposes of
inspiring
user confidence and further promoting visual and functional elegance, the
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thermostat 1800 is controlled by only two types of user input, the first being
a
rotation of the outer ring 1812 as shown in FIG. 18A (referenced hereafter as
a
"rotate ring" or "ring rotation" input), and the second being an inward push
on an
outer cap 1808 (see FIG. 18B) until an audible and/or tactile "click" occurs
(referenced hereafter as an "inward click" or simply "click" input). For the
embodiment of FIGS. 18A-18B, the outer cap 1808 is an assembly that includes
all
of the outer ring 1812, cover 1814, electronic display 1816, and metallic
portion
1824. When pressed inwardly by the user, the outer cap 1808 travels inwardly
by
a small amount, such as 0.5 mm, against an interior metallic dome switch (not
shown), and then springably travels back outwardly by that same amount when
the
inward pressure is released, providing a satisfying tactile "click" sensation
to the
user's hand, along with a corresponding gentle audible clicking sound. Thus,
for
the embodiment of FIGS. 18A-18B, an inward click can be achieved by direct
pressing on the outer ring 1812 itself, or by indirect pressing of the outer
ring by
virtue of providing inward pressure on the cover 1814, metallic portion 1814,
or by
various combinations thereof. For other embodiments, the thermostat 1800 can
be mechanically configured such that only the outer ring 1812 travels inwardly
for
the inward click input, while the cover 1814 and metallic portion 1824 remain
motionless. It is to be appreciated that a variety of different selections and
combinations of the particular mechanical elements that will travel inwardly
to
achieve the "inward click" input are within the scope of the present
teachings,
whether it be the outer ring 1812 itself, some part of the cover 1814, or some
combination thereof. However, it has been found particularly advantageous to
provide the user with an ability to quickly go back and forth between
registering
"ring rotations" and "inward clicks" with a single hand and with minimal
amount of
time and effort involved, and so the ability to provide an inward click
directly by
pressing the outer ring 1812 has been found particularly advantageous, since
the
user's fingers do not need to be lifted out of contact with the device, or
slid along its
surface, in order to go between ring rotations and inward clicks. Moreover, by
virtue of the strategic placement of the electronic display 1816 centrally
inside the
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rotatable ring 1812, a further advantage is provided in that the user can
naturally
focus their attention on the electronic display throughout the input process,
right in
the middle of where their hand is performing its functions. The combination of
intuitive outer ring rotation, especially as applied to (but not limited to)
the changing
of a thermostat's setpoint temperature, conveniently folded together with the
satisfying physical sensation of inward clicking, together with accommodating
natural focus on the electronic display in the central midst of their fingers'
activity,
adds significantly to an intuitive, seamless, and downright fun user
experience.
Further descriptions of advantageous mechanical user-interfaces and related
designs, which are employed according to some embodiments, can be found in
U.S. Ser. No. 13/033,573, supra, U.S. Ser. No. 29/386,021, supra, and U.S.
Ser.
No. 13/199,108, supra.
[0088] FIG. 18C illustrates a cross-sectional view of a shell portion
1809 of a
frame of the thermostat of FIGS. 18A-B, which has been found to provide a
particularly pleasing and adaptable visual appearance of the overall
thermostat
1800 when viewed against a variety of different wall colors and wall textures
in a
variety of different home environments and home settings. While the thermostat
itself will functionally adapt to the user's schedule as described herein and
in one
or more of the commonly assigned incorporated applications, supra, the outer
shell
portion 1809 is specially configured to convey a "chameleon" quality or
characteristic such that the overall device appears to naturally blend in, in
a visual
and decorative sense, with many of the most common wall colors and wall
textures
found in home and business environments, at least in part because it will
appear to
assume the surrounding colors and even textures when viewed from many
different
angles. The shell portion 1809 has the shape of a frustum that is gently
curved
when viewed in cross-section, and comprises a sidewall 1876 that is made of a
clear solid material, such as polycarbonate plastic. The sidewall 1876 is
backpainted with a substantially flat silver- or nickel- colored paint, the
paint being
applied to an inside surface 1878 of the sidewall 1876 but not to an outside
surface
1877 thereof. The outside surface 1877 is smooth and glossy but is not
painted.
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The sidewall 1876 can have a thickness T of about 1.5 mm, a diameter dl of
about
78.8 mm at a first end that is nearer to the wall when mounted, and a diameter
d2
of about 81.2 mm at a second end that is farther from the wall when mounted,
the
diameter change taking place across an outward width dimension "h" of about
22.5
mm, the diameter change taking place in either a linear fashion or, more
preferably,
a slightly nonlinear fashion with increasing outward distance to form a
slightly
curved shape when viewed in profile, as shown in FIG. 18C. The outer ring 1812
of outer cap 1808 is preferably constructed to match the diameter d2 where
disposed near the second end of the shell portion 1809 across a modestly sized
gap g1therefrom, and then to gently arc back inwardly to meet the cover 1814
across a small gap g2. It is to be appreciated, of course, that FIG. 18C only
illustrates the outer shell portion 1809 of the thermostat 1800, and that
there are
many electronic components internal thereto that are omitted from FIG. 18C for
clarity of presentation, such electronic components being described further
hereinbelow and/or in other ones of the commonly assigned incorporated
applications, such as U.S. Ser. No. 13/199,108, supra.
[0089] According to some embodiments, the thermostat 1800 includes a
processing system 1860, display driver 1864 and a wireless communications
system 1866. The processing system 1860 is adapted to cause the display driver
1864 and display area 1816 to display information to the user, and to receiver
user
input via the rotatable ring 1812. The processing system 1860, according to
some
embodiments, is capable of carrying out the governance of the operation of
thermostat 1800 including the user interface features described herein. The
processing system 1860 is further programmed and configured to carry out other
operations as described further hereinbelow and/or in other ones of the
commonly
assigned incorporated applications. For example, processing system 1860 is
further programmed and configured to maintain and update a thermodynamic
model for the enclosure in which the HVAC system is installed, such as
described
in U.S. Ser. No. 12/881,463, supra. According to some embodiments, the
wireless
communications system 1866 is used to communicate with devices such as
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personal computers and/or other thermostats or HVAC system components, which
can be peer-to-peer communications, communications through one or more
servers located on a private network, or and/or communications through a cloud-
based service.
[0090] FIGS. 19A-19B illustrate exploded front and rear perspective views,
respectively, of the thermostat 1800 with respect to its two main components,
which are the head unit 1900 and the back plate 2000. Further technical and/or
functional descriptions of various ones of the electrical and mechanical
components illustrated hereinbelow can be found in one or more of the commonly
assigned incorporated applications, such as U.S. Ser. No. 13/199,108, supra.
In
the drawings shown, the "z" direction is outward from the wall, the "y"
direction is
the head-to-toe direction relative to a walk-up user, and the "x" direction is
the
user's left-to-right direction.
[0091] FIGS. 20A-20B illustrate exploded front and rear perspective
views,
respectively, of the head unit 1900 with respect to its primary components.
Head
unit 1900 includes a head unit frame 1910, the outer ring 1920 (which is
manipulated for ring rotations), a head unit frontal assembly 1930, a front
lens
1980, and a front grille 1990. Electrical components on the head unit frontal
assembly 1930 can connect to electrical components on the backplate 2000 by
virtue of ribbon cables and/or other plug type electrical connectors.
[0092] FIGS. 21A-21B illustrate exploded front and rear perspective
views,
respectively, of the head unit frontal assembly 1930 with respect to its
primary
components. Head unit frontal assembly 1930 comprises a head unit circuit
board
1940, a head unit front plate 1950, and an LCD module 1960. The components of
the front side of head unit circuit board 1940 are hidden behind an RF shield
in
FIG. 21A but are discussed in more detail below with respect to FIG. 24. On
the
back of the head unit circuit board 1940 is a rechargeable Lithium-Ion battery
1944,
which for one preferred embodiment has a nominal voltage of 3.7 volts and a
nominal capacity of 560 mAh. To extend battery life, however, the battery 1944
is
normally not charged beyond 450 mAh by the thermostat battery charging
circuitry.
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Moreover, although the battery 1944 is rated to be capable of being charged to
4.2
volts, the thermostat battery charging circuitry normally does not charge it
beyond
3.95 volts. Also visible in FIG. 21B is an optical finger navigation module
1942 that
is configured and positioned to sense rotation of the outer ring 1920. The
module
1942 uses methods analogous to the operation of optical computer mice to sense
the movement of a texturable surface on a facing periphery of the outer ring
1920.
Notably, the module 1942 is one of the very few sensors that is controlled by
the
relatively power-intensive head unit microprocessor rather than the relatively
low-
power backplate microprocessor. This is achievable without excessive power
drain
implications because the head unit microprocessor will invariably be awake
already
when the user is manually turning the dial, so there is no excessive wake-up
power
drain anyway. Advantageously, very fast response can also be provided by the
head unit microprocessor. Also visible in FIG. 21A is a Fresnel lens 1957 that
operates in conjunction with a PIR motion sensor disposes thereunderneath.
[0093] FIGS. 22A-22B illustrate exploded front and rear perspective views,
respectively, of the backplate unit 2000 with respect to its primary
components.
Backplate unit 2000 comprises a backplate rear plate 2010, a backplate circuit
board 2020, and a backplate cover 2080. Visible in FIG. 22A are the HVAC wire
connectors 2022 that include integrated wire insertion sensing circuitry, and
two
relatively large capacitors 2024 that are used by part of the power stealing
circuitry
that is mounted on the back side of the backplate circuit board 2020 and
discussed
further below with respect to FIG. 25.
[0094] FIG. 23 illustrates a perspective view of a partially assembled head
unit
front 1900 showing the positioning of grille member 1990 designed in
accordance
with aspects of the present invention with respect to several sensors used by
the
thermostat. In some implementations, as described further in U.S. 13/199,108,
supra, placement of grille member 1990 over the Fresnel lens 1957 and an
associated PIR motion sensor 334 conceals and protects these PIR sensing
elements, while horizontal slots in the grille member 1990 allow the PIR
motion
sensing hardware, despite being concealed, to detect the lateral motion of
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occupants in a room or area. A temperature sensor 330 uses a pair of thermal
sensors to more accurately measure ambient temperature. The first or upper
thermal
sensor 330a associated with temperature sensor 330 tends to gather temperature
data closer to the area outside or on the exterior of the thermostat while a
second
or lower thermal sensor 330b tends to collect temperature data more closely
associated with the interior of the housing. In one implementation, each of
the
temperature sensors 330a and 330b comprises a Texas Instruments TMP112
digital temperature sensor chip, while the PIR motion sensor 334 comprises
PerkinElmer DigiPyro PYD 1998 dual element pyrodetector.
[0095] To more accurately determine the ambient temperature, the
temperature
taken from the lower thermal sensor 330b is taken into consideration in view
of the
temperatures measured by the upper thermal sensor 330a and when determining
the effective ambient temperature. This configuration can advantageously be
used
to compensate for the effects of internal heat produced in the thermostat by
the
microprocessor(s) and/or other electronic components therein, thereby
obviating or
minimizing temperature measurement errors that might otherwise be suffered. In
some implementations, the accuracy of the ambient temperature measurement
may be further enhanced by thermally coupling upper thermal sensor 330a of
temperature sensor 330 to grille member 1990 as the upper thermal sensor 330a
better reflects the ambient temperature than lower thermal sensor 334b.
Details on
using a pair of thermal sensors to determine an effective ambient temperature
is
disclosed in U. S. Pat. 4741476.
[0096] FIG. 24 illustrates a head-on view of the head unit circuit board
1940,
which comprises a head unit microprocessor 2402 (such as a Texas Instruments
AM3703 chip) and an associated oscillator 2404, along with DDR SDRAM memory
2406, and mass NAND storage 2408. For Wi-Fl capability, there is provided in a
separate compartment of RE shielding 2434 a Wi-Fi module 2410, such as a
Murata Wireless Solutions LBWA19XSLZ module, which is based on the Texas
Instruments WL1270 chipset supporting the 802.11 b/g/n WLAN standard. For the
Wi-Fi module 2410 is supporting circuitry 2412 including an oscillator 2414.
For
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ZigBee capability, there is provided also in a separately shielded RF
compartment
a ZigBee module 2416, which can be, for example, a C2530F256 module from
Texas Instruments. For the ZigBee module 2416 there is provided supporting
circuitry 2418 including an oscillator 2419 and a low-noise amplifier 2420.
Also
provided is display backlight voltage conversion circuitry 2422, piezoelectric
driving
circuitry 2424, and power management circuitry 2426 (local power rails, etc.).
Provided on a flex circuit 2428 that attaches to the back of the head unit
circuit
board by a flex circuit connector 2430 is a proximity and ambient light sensor
(PROX/ALS), more particularly a Silicon Labs SI1142 Proximity/Ambient Light
Sensor with an I2C Interface. Also provided is battery charging-supervision-
disconnect circuitry 2432, and spring/RE antennas 2436. Also provided is a
temperature sensor 2438 (rising perpendicular to the circuit board in the +z
direction containing two separate temperature sensing elements at different
distances from the circuit board), and a PIR motion sensor 2440. Notably, even
though the PROX/ALS and temperature sensors 2438 and PIR motion sensor 2440
are physically located on the head unit circuit board 1940, all these sensors
are
polled and controlled by the low-power backplate microcontroller on the
backplate
circuit board, to which they are electrically connected.
[0097] FIG. 25 illustrates a rear view of the backplate circuit board
2020,
comprising a backplate processor/microcontroller 2502, such as a Texas
Instruments MSP430F System-on-Chip Microcontroller that includes an on-board
memory 2503. The backplate circuit board 2020 further comprises power supply
circuitry 2504, which includes power-stealing circuitry, and switch circuitry
2506 for
each HVAC respective HVAC function. For each such function the switch
circuitry
2506 includes an isolation transformer 2508 and a back-to-back NFET package
2510. The use of FETs in the switching circuitry allows for "active power
stealing",
i.e., taking power during the HVAC "ON" cycle, by briefly diverting power from
the
HVAC relay circuit to the reservoir capacitors for a very small interval, such
as 100
micro-seconds. This time is small enough not to trip the HVAC relay into the
"off"
state but is sufficient to charge up the reservoir capacitors. The use of FETs
allows
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for this fast switching time (100 micro-seconds), which would be difficult to
achieve
using relays (which stay on for tens of milliseconds). Also, such relays would
readily degrade doing this kind of fast switching, and they would also make
audible
noise too. In contrast, the FETS operate with essentially no audible noise.
Also
provided is a combined temperature/humidity sensor module 2512, such as a
Sensirion SHT21 module. The backplate microcontroller 2502 performs polling of
the various sensors, sensing for mechanical wire insertion at installation,
alerting
the head unit regarding current vs. setpoint temperature conditions and
actuating
the switches accordingly, and other functions such as looking for appropriate
signal
on the inserted wire at installation.
[0098] In
accordance with the teachings of the commonly assigned U.S. Ser.
No. 13/269,501, supra, the commonly assigned U.S. Ser. No. 13/275,307, supra,
and others of the commonly assigned incorporated applications, the thermostat
1800 represents an advanced, multi-sensing, microprocessor-controlled
intelligent
or "learning" thermostat that provides a rich combination of processing
capabilities,
intuitive and visually pleasing user interfaces, network connectivity, and
energy-
saving capabilities (including the presently described auto-away/auto-arrival
algorithms) while at the same time not requiring a so-called "C-wire" from the
HVAC system or line power from a household wall plug, even though such
advanced functionalities can require a greater instantaneous power draw than a
"power-stealing" option (i.e., extracting smaller amounts of electrical power
from
one or more HVAC call relays) can safely provide. By way of example, the head
unit microprocessor 2402 can draw on the order of 250 mW when awake and
processing, the LCD module 1960 can draw on the order of 250 mW when active.
Moreover, the Wi-Fi module 2410 can draw 250 mW when active, and needs to be
active on a consistent basis such as at a consistent 2% duty cycle in common
scenarios. However, in order to avoid falsely tripping the HVAC relays for a
large
number of commercially used HVAC systems, power-stealing circuitry is often
limited to power providing capacities on the order of 100 mW ¨200 mW, which
would not be enough to supply the needed power for many common scenarios.
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[0099] The thermostat 1800 resolves such issues at least by virtue of the
use of
the rechargeable battery 1944 (or equivalently capable onboard power storage
medium) that will recharge during time intervals in which the hardware power
usage is less than what power stealing can safely provide, and that will
discharge
to provide the needed extra electrical power during time intervals in which
the
hardware power usage is greater than what power stealing can safely provide.
In
order to operate in a battery-conscious manner that promotes reduced power
usage and extended service life of the rechargeable battery, the thermostat
1800 is
provided with both (i) a relatively powerful and relatively power-intensive
first
processor (such as a Texas Instruments AM3703 microprocessor) that is capable
of quickly performing more complex functions such as driving a visually
pleasing
user interface display and performing various mathematical learning
computations,
and (ii) a relatively less powerful and less power-intensive second processor
(such
as a Texas Instruments MS P430 microcontroller) for performing less intensive
tasks, including driving and controlling the occupancy sensors. To conserve
valuable power, the first processor is maintained in a "sleep" state for
extended
periods of time and is "woken up" only for occasions in which its capabilities
are
needed, whereas the second processor is kept on more or less continuously
(although preferably slowing down or disabling certain internal clocks for
brief
periodic intervals to conserve power) to perform its relatively low-power
tasks. The
first and second processors are mutually configured such that the second
processor can "wake" the first processor on the occurrence of certain events,
which
can be termed "wake-on" facilities. These wake-on facilities can be turned on
and
turned off as part of different functional and/or power-saving goals to be
achieved.
For example, a "wake-on-PROX" facility can be provided by which the second
processor, when detecting a user's hand approaching the thermostat dial by
virtue
of an active proximity sensor (PROX, such as provided by a Silicon Labs SI1142
Proximity/Ambient Light Sensor with I2C Interface), will "wake up" the first
processor so that it can provide a visual display to the approaching user and
be
ready to respond more rapidly when their hand touches the dial. As another
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example, a "wake-on-PIR" facility can be provided by which the second
processor
will wake up the first processor when detecting motion somewhere in the
general
vicinity of the thermostat by virtue of a passive infrared motion sensor (PIR,
such
as provided by a PerkinElmer DigiPyro PYD 1998 dual element pyrodetector).
Notably, wake-on-PIR is not synonymous with auto-arrival, as there would need
to
be N consecutive buckets of sensed PIR activity to invoke auto-arrival,
whereas
only a single sufficient motion event can trigger a wake-on-PIR wake-up.
[00100] FIGS. 26A-26C illustrate conceptual examples of the sleep-wake timing
dynamic, at progressively larger time scales, that can be achieved between the
head unit (HU) microprocessor and the backplate (BP) microcontroller that
advantageously provides a good balance between performance, responsiveness,
intelligence, and power usage. The higher plot value for each represents a
"wake"
state (or an equivalent higher power state) and the lower plot value for each
represents a "sleep" state (or an equivalent lower power state). As
illustrated, the
backplate microcontroller is active much more often for polling the sensors
and
similar relatively low-power tasks, whereas the head unit microprocessor stays
asleep much more often, being woken up for "important" occasions such as user
interfacing, network communication, and learning algorithm computation, and so
forth. A variety of different strategies for optimizing sleep versus wake
scenarios
can be achieved by the disclosed architecture and is within the scope of the
present teachings. For example, the commonly assigned U.S. Ser. No.
13/275,307, supra, describes a strategy for conserving head unit
microprocessor
"wake" time while still maintaining effective and timely communications with a
cloud-based thermostat management server via the thermostat's Wi-Fi facility.
[00101] FIG. 27 illustrates a self-descriptive overview of the functional
software,
firmware, and/or programming architecture of the head unit microprocessor 2402
for achieving its described functionalities. FIG. 28 illustrates a self-
descriptive
overview of the functional software, firmware, and/or programming architecture
of
the backplate microcontroller 2502 for achieving its described
functionalities.
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[00102] FIG. 29 illustrates a view of the wiring terminals as presented to the
user
when the backplate is exposed. As described in the commonly assigned U.S. Ser.
No. 13/034,666, supra, each wiring terminal is configured such that the
insertion of
a wire thereinto is detected and made apparent to the backplate
microcontroller
and ultimately the head unit microprocessor. According to a preferred
embodiment, if the insertion of a particular wire is detected, a further check
is
automatically carried out by the thermostat to ensure that signals appropriate
to
that particular wire are present. For one preferred embodiment, there is
automatically measured a voltage waveform between that wiring node and a
"local
ground" of the thermostat. The measured waveform should have an RMS-type
voltage metric that is above a predetermined threshold value, and if such
predetermined value is not reached, then a wiring error condition is indicated
to the
user. The predetermined threshold value, which may vary from circuit design to
circuit design depending on the particular selection of the local ground, can
be
empirically determined using data from a population of typical HVAC systems to
statistically determine a suitable threshold value. For some embodiments, the
"local ground" or "system ground" can be created from (i) the Rh line and/or
Rc
terminal, and (ii) whichever of the G, Y, or W terminals from which power
stealing is
being performed, these two lines going into a full-bridge rectifier (FWR)
which has
the local ground as one of its outputs.
[00103] While examples and implementations have been described, they should
not serve to limit any aspect of the present invention. Accordingly, various
modifications may be made without departing from the spirit and scope of the
invention. Indeed, while the occupancy sensor positioned behind the grille
member
is characterized in one or more embodiments supra as being a PIR sensor, for
which the above-described configurations are particularly advantageous, the
scope
of the present teachings is not so limited. Moreover, it is to be appreciated
that
while the grille member is characterized in one or more embodiments supra as
being generally forward-facing, which is useful for more common scenarios in
which the thermostat is mounted on a wall at a moderate height above the floor
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that makes it easy to reach, the scope of the present teachings is not so
limited. By
way of example, there is provided in some further embodiments a thermostat,
comprising a housing including a region of interest-facing surface (R01-facing
surface), where the ROI corresponds to the relevant area or volume of the
house
(or other enclosure) for which occupancy or occupancy-related events are to be
sensed. The thermostat further includes an occupancy sensor disposed inside
the
housing and used to sense occupancy in the ROI, the occupancy sensor having at
least one receiving surface and being able to detect the presence and/or
movement of the occupant in the ROI. The thermostat further includes a grille
member having one or more openings and included along the ROI-facing surface
of the housing and placed over the one or more receiving surfaces of the
occupancy sensor that substantially conceals and protects the occupancy sensor
disposed inside the housing, whereby the concealment of the occupancy sensor
by
the grille member promotes a visually pleasing quality of the thermostat yet
permits
the occupancy sensor to effectively detect the presence and/or movement of the
occupant in the ROI. The ROI-facing surface can be a forward-facing surface
for a
conventional wall-mounted location, or can be a downward-facing surface
(including a diagonally-outward downward angle) for a mounting location that
is
above a doorway, for example, such that persons going in and out of the room
are
sensed. The occupancy sensor can include, for example, one or more of a PIR
sensor, an actively transmitting proximity sensor, an ambient light sensor,
and an
ultrasound sensor. In the case of a PIR sensor and a mounting location over
the
doorway, the slotted openings in the grille member can be oriented in a
direction
normal to the door opening, such that movement toward and away from the door
is
more optimally sensed. It is to be further appreciated that the term
thermostat, as
used hereinabove and hereinbelow, can include thermostats having direct
control
wires to an HVAC system, and can further include thermostats that do not
connect
directly with the HVAC system, but that sense an ambient temperature at one
location in an enclosure and cooperatively communicate by wired or wireless
data
connections with a separate thermostat unit located elsewhere in the
enclosure,
CA 02818396 2013-05-16
WO 2012/068507 PCT/US2011/061479
- 43 -
wherein the separate thermostat unit does have direct control wires to the
HVAC
system. Accordingly, the invention is not limited to the above-described
implementations, but instead is defined by the appended claims in light of
their full
scope of equivalents.
