THERMOSTAT A MINUTERIE A PILES

TIME CONTROLLED THERMOSTAT WITH BATTERY OPERATED TIMER

Abrégé anglais

ABSTRACT OF THE DISCLOSURE
A two wire rechargeable battery powered electric
time controlled thermostat apparatus adapted to be connected
by two wires to a source of alternating current voltage and
control apparatus for controlling the supply of temperature
condition medium to the space wherein the thermostat is
located with a rectifying circuit means in the thermostat ap-
paratus for recharging the battery from the source over the
two wires.

Revendications

The embodiments of the invention in which an exclu-
sive property or right is claimed are defined as follows:
1. An improvement in a two wire electric clock tempera-
ture control wherein a rechargeable battery powered clock ther-
mostat unit, comprising a continuously energized clock motor
and a thermostat means, is adapted to be located in a space
and is adapted to be connected by two wires to a remote second
unit comprising an alternating current power source and a con-
trol apparatus for controlling the operation of temperature con-
ditioning apparatus supplying temperature conditioned medium
to the space, the improvement comprising
rectifying means mounted in the thermostat unit,
and
circuit connecting means adapted for connecting said
power source through said two wires and said rectifying means
to the rechargeable battery to charge said battery.
2. The invention of claim 1 comprising,
current limiting means connected in said circuit
connecting means to limit the current to said rectifying means
to prevent operation of the control apparatus by a current flow
to said battery during the charging of said battery.
3. The invention of claim 1 wherein
said rectifying means comprises a diode bridge cir-
cuit to provide charging current to said battery on both cycles
of said alternating current power source.
4. In a two wire rechargeable battery powered electric
time controlled temperature control adapted to be connected by
two wires to a source of voltage and control apparatus for con-

Claim 4 continued
trolling the temperature of temperature conditioned medium de-
livered to a space wherein the control is to be located com-
prising,
temperature responsive control means,
electric time controlled means connected to said
temperature responsive control means to change the control
temperature to be maintained by said temperature responsive
control means during different time periods,
rechargeable battery means electrically connected
to energize said electric time controlled means, and
circuit means adapted to connect said battery means
to said two wires to charge said battery means.
5. The invention of claim 4 wherein
said source is an alternating current voltage source,
and
said circuit means comprises rectifying means to
convert power from said source to a unidirectional current
for charging said battery.
6. The invention of claim 5 comprising:
current limiting means connected in said circuit
means to limit the power drawn over said two wires for
charging said battery to prevent operation of the control
apparatus when the temperature control is not calling for
temperature conditioning.
7. The invention of claim 4 wherein;
said circuit means is adapted to connect said
battery to said source all the time.
8. The invention of claim 7 comprising:

Claim 8 continued
current limiting means connected in said circuit
means to limit the current drawn over said two wires to
charge said battery.

9. A unitary electrical time variable set point thermostatic device
adapted for use in a two wire control circuit of a heating system without
additional wiring comprising:
a. thermostatic control means having temperature set points and
responsive to ambient temperature for opening and closing a
thermostatic switch therein, said switch energizing said
control circuit to operate said heating system when said
ambient temperature varies a determined amount from said set
point;
b. electric timer means for cyclically changing said set point of
said thermostatic means from an initial value at a selected
time to a second value and at a selected time thereafter restor-
ing said set point to said initial value;
c. electrical energy storage means for continuously energizing
said timer means independent of said two wire control circuit,
said electrical energy storage means comprising a battery con-
nected to said electric timer means; and
d. means connected in said control circuit for charging said
battery during periods when said switch of said thermostatic
control means is open.
10. A device as defined in claim 9 wherein said electic timer means
includes an electric motor connected to said thermostatic control means for
mechanically changing said set point of said thermostatic control means at
said selected times.
11. A device as defined in claim 9 wherein said charging means comprises:
a. a diode, and

b. a charging resistor series connected with said diode and
said battery, said diode blocking current flow from said
battery except through said motor when said switch of said
thermostatic control means is closed.

Description

443
TIME CO~TROLLED THERMOSTAT
BACKGROU~D A~D SUMMARY OF THE INVE~TION ..
Time controlled or electric clock thermostats have
for many years required at least three wires to connect the .
thermostat to a remote source of power and a control apparatus
for a system for controlling the supply of temperature condi- ~
tion medium to the space wherein the thermostat is located. ¦:
In the modification of original construction in which two
wires are required for a simple thermostat, considerable dif-
ficulty is experienced when the system is to be converted for .
use with a clock thermostat as extra wires are pulled through
the wall.
To overcome the necessity of pulling extra wires : :~
to power a clock thermostat over the same two wires on which
the control apparatus is controlled, various expensive schemes
have been provided such as in the United States Clifford L. ~ ~ :
i Nelson et al Patent 3,620,448, issued ~ovember 16, 1971, and
: the United States Balthasar H. Pinckaers Patent 3,599,863,
issued August 17, 1971, wherein the clock motor is powered :
over the two wires and a signal of a diferent power factor
or waveform is superimposed over the two wires for controlling
: the remote control apparatus. :
Obviously, with the advent of lower power, extremely
accurate battery driven time controlled units or clocks, such ~
as the crystal oscillator type now available, the use of such ¦
a motor for powering an electric clock thermostat has been pro- ~
posed, however, because of the torque requirement that the ~ :.
motor must have to do the added work of directly moving a
: mechanism which changes the temperature maintained in the
space, power required from such a battery is large enough that
,, , .

443 : ~ ~
that frequent changing or recharging of the battery must be accomplished. .
The present invention provides a rechargeable battery powered
electric clock thermostat for use in a system for controlling remote control ~-
apparatus over two wires and for connecting the battery through a charging .
circuit over the same two wires to a remote power source; so that, an
electric clock thermostat can be used to replace a simple thermostat without
the expense of additional wires for providing a control circuit for the -
thermostat and an energization circuit for the clock motor.
Thus, in accordance with one broad aspect of the invention, there -~
is provided an improvement in a two wire electric clock temperature control -~
wherein a rechargeable battery powered clock thermostat unit, comprising a
continuously energized clock motor and a thermostat means, is adapted to be ; :~
located in a space and is adapted to be connected by two wires to a remote
second unit comprising an alternating current power source and a control ~-
apparatus for controlling the operation of temperature conditioning apparatus ;-~
supplying temperature conditioned medium to the space, the improvement . :~
comprising rectifying means mounted in the thermostat unit, and circuit
connecting means adapted for connecting sald power source through said two .~ ~
. wires and said rectifying means to the rechargeable battery to charge said ~-
~:: 20 battery. ;:
According to another broad aspect of the invention there is pro~
vided, in a two wire rechargeable battery powered electric time controlled
temperature control adapted to be connected by two wires to a source of
voltage and control apparatus for controlling the temperature of temperature :~
: conditioned medium delivered to a space wherein the control is to be located ~:
comprising, temperature responsive control means, electric time controlled
means connected to said temperature respons~ve control means to change the ;~
: control ~cemperature to be maintained by said temperature responsive control
: means during different time periods, rechargeable battery means electrically
connected to energize said electric time controlled means, and circuit means
adapted to connect said battery meane to said two wires to charge said
battery means.
,
~ -2-
;~ . , , . , , - . ::.

443
The embodiments of the present invention are shown in the
following figures of which
Figure 1 is a schematic showing of the connection of a battery
powered time controlled thermostat apparatus to a remote source of power
and control apparatus for controlling the supply of temperature condition
medium to the space in which the thermostat is mounted, and .
Figure 2 is a first embodiment of the present invention, and ~ .
Figure 3 is another embodiment of the invention, and ~-
Figure 4 is still another embodiment of the invention. ;~
DESCRIPTION OF THE INVENTION ::-
. ~ .,
Referring to Figure 1, the temperature in a space 10 is controlled :~
by a temperature responsive device or thermostat apparatus 11 connected by :
two wires 12 and 13 to a remote control panel 14. Panel 14 has a source of ~ :
power 15 and an output circuit 20 connected to a control apparatus or valve
21 of a system for controlling the supply of fuel or gas to a tempera-
,~ :
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,. . , . -

lOg¢443
ture conditioning apparatus or furnace 22 for temperature con-
ditioning or heating medium or air being circulated through
t~e space 10 through duct 23 by a fan 24.
Thermostat apparatus 11 has a temperature responsi~e
control means or mechanism for maintaining one of two different
levels of temperature or bimetal operated switch means 25, such
as a clock thermostat disclosed in the United States Carl. G ¦ `
Kronmiller Patent 2,558,617, issued June 26, 1951, comprising ¦
a bimetal element which controls a switch to complete a circuit
to provide power to remote control apaaratus 21. The tempera-
ture control of the thermostat apparatus 11 is adjusted by a
time controlled mechanism or clock driven by a motor 30 to
selectively adjust the control temperature maintained during
different time periods to typically maintain a daytime tempera-
ture of 72 and at 10:00 p.m. to change the control point of the
thermostat to maintain a nighttime temperature of 65 until
morning when the daytime temperature is again selected. Any
one particular type of thermostat apparatus 11 for 9electively-
maintaining different controlled temperatures in a space 10
~: ~ :
~: ao is not required for use in the present invention. Motor 30 is
a rechargeable battery powered motor connected to a battery 32 ~
whlch is recharged over the same two wires 12 and 13 by;a charging
` circuit to be described.
,
~ Referring to Figure 2, thermostat lI is shown con-
.',
`' 25 nected to panel 14 ~or controlling control apparatus or valve ¦
21. Temperature responslve switch 25 is adapted to connect ¦
the control circuit to the source of power 15 to ener~ize valve J
21. Circuit 31 is an adjustable circuit or energizing con-
ventional anticipation heater 26 thermally connected to tem-
perature responsive switch means 25. The voltage to heater
26, can be adjusted by selectively positioning input tap 27

4~3
to regulate the control of thermostat switch 25. ~otor 30 is
connected to rechargeable battery 32 for driving the time con-
trolled mechanism of thermostat 11. One terminal of battery
32 is connected by conductor 33 to a diode 34 to wire 12 and.
the other terminal of the battery is connected by conductor 35 r
through a limiting resistor 40 to the other wire 13 for pro-
viding a charging circuit to battery 32.
The battery is charged from source 15 all the time.
By means of a limiting resistor 40, the current drain from the.
source for the recharging of the battery is limited below that L
required to operate valve 21. The valve 21 will not operate
when the thermostat is not calling for heat.
The embodiment of the invention shown in Figure 3
comprises the thermostat 11 connected over wires 12 and 13 to
panel 14 with the source of power 15 and valve 21. The ther-~
mostat switch 25 is connected in parallel with motor 30 so that
when the switch is open current is suppl.ied through the diode
34 to recharge battery 32. A limiting resistor ~40 is connecte
to limit the current to prevent the operation of valve 21.
. ,
The embodiment of the invention as shown in Figure 4
has a thermostat 11 connected over two wires 12 and 13 to a
remote panel 14 having a source of power 15 and a valve 21. ~ ~:
Rectifying means 34 for supplying power to recharge battery 32 .
comprises a conventional diode bridge for providing a recti- ¦
fying current during both cycles of the alternating current ¦ ~
voltage of source 15. The current drain from the source is I .:
limited by limiting resistor 40. !