Note: Descriptions are shown in the official language in which they were submitted.
~2S4~S~
This application has been divided out of Canadian Patent
Appllcation Serial No. 480,291 filed April 29, 1985.
The invention relates to a beverage-making dev;ce which constitutes
an 3mprovement over the prior art, particularly direc~ed to those devices
which automatically brew coffee.
In such devices, a water supply l;ne is in direct com munication
with an inlet valve for on-demand admittance of cold water to a water-
heating container in which a constant source of hot water for brewing
is avai]able. The inlet valve is electrically operated to open ~or a pre-
set bre~ing cycle equal to the amount of t;me required to provide
sufficient liquid to fill a receiving decanter, such as a coffee pot.
A running thermostat senses the temperature in the water container
and electrically communicates with a coiled, or looped, heat;ng element
so that the constant desired temperature is maintained.
~ 7ater systems for admitting cold water to the container include
inlet tube means for dispensing the incoming water at the bottom of the
container. As the cold water enters, displaced volumes of hot water at
the top of the container are siphoned from the container to a brewing
chamber, which is manually pre-filled with a load of fresh ground coffee.
As incoming water reduces the ~1ater temperature in the container, the
running thermostat senses this lower temperature and activates ihe heating
element. The heating element remains energized until the thermostat
senses that the required water temperature has been reached. With high
capacity e]ectric heating elements, a substantial temperature increase
occurs over A short period of time. Should the running thermostat fail
in the on position, a so-called "run away" condition will result whereby
the heater will stay energized. Thereafter, the heating element will
quickly evaporate the water and reach a dangerously high temperature.
In order to prevent overheating, conventional systems include high limit
thermostats. A high limit thermostat serves to de-activate the heating
e1ement when e~:cessive temperatures are sensed. This safety feature is
particularly useful ~hen someone has inadvertently failed to fill the water
container prior to initiating a brewing cycle. ~'ithout this feature the
running thermostat would b]indly sense the ambient air temperature inside
the empty container. In response, the heating element ~ould continue
lo operate until reaching a dAngerous "red-hot" condition.
~L~59~Q~i~
Customsrily, the hot water container is provided with a
hermetically sealed cover which supportive]y accomodates the aforesaid
siphon, running and high limit thermostats, and in]et tube means, as well
as the terminals for the heating element. A drawback to this typical
arrangement is that only the temperature at the cover is sensed by the
high ]imit thermostat. As a result, an excessively high temperature at
lower portions of the container, localized near the heating element, can
sometimes occur while the cover remains relatively cool. The remote
disposition of a high limit thermostat at the container cover is inherently
inefficient for detecting these temperature fluctuations at the bottom
half of the container. A thermostat system which can immediately detect
this dangerous condition, and promptly de-activate the heating element,
wou]d be a significant achievement.
Running thermostats are typically connected to an en]arged sensing
bulb by means of a thin capillary tube. The bulb end is usl~ally positioned
at the lower half of the container. The capillary tube must therefore
extend downwardly into the container to reach the bulb end. A ]ong
guide s]eeve is used to hold the bulb in p]ace. The guide sleeve is
attached to the cover and extends downwardly into the container to
surround and protect the capillary tube and the full length of the en]arged
bu]b end. Usually, guide sleeves are secured to the bottom of the heating
coil so that the bulbs are fixed in the proper orientation. De~iciencies
in this conventional arrangement have been encountered. Firstly, the
en]arged bulb end is limited to only sensing temperatures in the vicinity
of the bottom half or third of the container. Temperatures at the upper
portions are not detected, and may In fact be sufficiently high to brew
coffee without further activation of the heating coil. It would be
considerably more advantageous to detect the mean temperature of the
entire water volume. Secondly, conventional enlarged bulb thermostats
have a temperature-sensing spread of about 6-8~ F. Thereby, the heating
e~ement is not qu}ckly activated when the water becomes too cool and,
once activated, will unnecessarily remain on for a period of time after
the water has reached the desired temperature. A thermostat arrangement
that reacts to smaller temperature changes would be economically
beneficial, since the heater would be activated soon after the water falls
125~105~
below the usuRl brewing temperature of 205F. and then de-activated
very shortly after this is attained.
The guide sleeve arrangements in the prior art have hindered
maintenance procedures. In order to remove the thermostat and bulb
for repair, the cover has had to be removed in order to disconnect the
guide sleeve from the heating element. It would be a great aid to repair
personnel to eliminate the need for a guide sleeve and provide a running
thermostat, capil]ary tube and sensing tube that are completely
disengageable from the device without requiring other components, such
as the cover, to be disconnected or disturbed. A self-supporting sensing
means would greatly advance the solution to this problem. Savings in
maintenance time and repair costs would be made.
Automatic be~erage-making devices have also included means for
dispensing hot water for making tea, instant soup and the like. In the
past these systems simply drained hot ~ater directly from the water
container. By extracting a volume of hot water from the container, the
bre~ing capability of the device is diminished. Should a contemporaneous
brewing cycle be desired, the container must first be re-fi]led with colder
inlet u ater and then heated to elevate the temperature of the water to
the necessary brewing level. The re-filling step has usually been initiated
by the provision of a float switch arranged in the upper portion of the
container which detects the drop in the water level. The inlet valve is
electrically controlled by the switch which signals it to open until the
float is satisfied. Due to lime build-up the switches can close and become
inoperable. A hot water system that eliminates the need for a float
switch would be a significant advance in the art. It wou~d also be a
valuable improvement to provide a hot water s~stem which does not
borrow from the water in the container but still makes hot water
instantaneously avai]able for these other purposes.
In order to distribute the siphoned hot water over the coffee
grounds, typical beverage-making devices utilize resiliently biased spray
means over which the siphoned uater is directed. The spray means is
usually a flat, perforate disk. Other devices have used a sho\~erhead
type arrangernent wherein a siphon tube nozzle lluidly communicates ~ith
a spray means that is concave rather than disk-shaped. Spray means, ;n
either form, provide for sprinkling hot water over the coffee grounds,
~z~
which are disposed in the brewing basket, or chamber, therebelow. For
effective brewing to take place, a lazy drip îrom the spray means is
preferred for a uniform distribution of hot water over the ground coffee.
A common prob]em, particularly with flat spray disks, has been that the
siphoned water is too forcefully emitted in streams through a series of
disk orifices which create an equal number of holes bored into the mound
of cof~ee grounds. Quite oppositely, the desired drip phenomenon is an
even flow over the grounds. It would therefore be of great value to
provide a moderately paced gravity drip system ~hich elim;nates individual
spray streams through the dis~ orifices onto the ground coffee. Spray
disks also require cleaning due to the accurnulation of lime deposits and
other sediments found in water lines. As a result, the disks need to be
removed for clean;ng. The usual resilient connections between spray
disks and associated mounting collars render the disks removable, but are
inadequAte for achieving a tight engagement therebetween. A tight seal
bet~een the periphery of the spray disk and mounting collar is highly
desirable so that the siphoned hot ~Yater will not leflk around the edges
of the disk, but will be emitted only through the orifices.
Accordingly, a more effective interconnection between a spray disk
and mounting collar would be a significant improvement over the roregoing
devices. A positively locking connection would avoid the disadvantages
of the resilient connections found in the prior art. It would.also be
beneficial to provide a tight sealed engagement that also snugly lodges
a flexible gasket between the outer edge of the disk and the collar.
rhereby, edge leakage ~1ould be prevented and a random drip pattern
attained for the preferred even distribution of hot water over the coffee
grounds.
For standard size automatic beverage-making devices, the hot water
container normally holds at lesst three times the vo]ume of a conventional
coffee pot and usually takes the forrn of cylinder having a greater height
than w idth. Cleaning these relatively ]arge containers is necessary for
taste and sanitary reasons. In order to remove sedimentation, such as
]ime deposits, the prevailing technique involves operating the beverage-
m~ing device for several cycles with a de-liming solution pumE~ed through
the container. Orten, sediments st the container bottom are not dissolved
and must be manually removed. In a more rudimentary c]eaning method,
~Z5~63 5~
the container is simply tipped over to empty the water. The
latter is clearly an awkward and undesirable technique. A
bottom drain, which allows the container to be fully emptied,
would be preferable. Prior art devices have failed to provide
a separate bottom draining system, proba~ly due to the
problems encountered with attaching drain tubes. The customary
manner of affixing drains to metal containers is by welding.
A disadvantage to such fittings is that the welds corrode and
result in leakaye. Welding also creates a fixed drain
connection which impedes removing the con-tainer for repair and
otherwise generally limits access to other components inside
the device. It would accordingly be of significant value to
provide a non~welded bottom drain system which avoids corrosion
and leakage problems. In addition, it would be advantageous
for the drain system to be disengageable to permit easy access
to the interior of the device for the repair, or replacement,
of mechanical and electrical components.
The present invention offers an improvement for beverage-
making devices of the type described, which satisfies the
needs set forth above.
A unique container draining system is provided which
associates with an aperture at the bottom of the hot water
container. The system includes a flanged drain fitting partly
arranged interiorly of the container and partly extending
through the aperture to be thread-engaged with an elbow and
coupling assembly in a tightly sealed connection. A
conventional valve is connected to the coupling means and is
manually operable to facilitate emptying the water container.
The system eliminates the problems with welding and affords
quick disengagement from the container to allow easy access
to the interior of the device.
Specifically, the invention provides in a beverage-making
device of the type having a hot water contalner positioned
interiorly of a housing, means for conveying cold water to the
container and outlet means for discharging hot water therefrom,
the improvement comprising a bottom drain system disengageably
secured to the bottom of the container at a drain hole
~Z54L~S~
therethrough, said drain system including a drain fitting
having a flanged seat arranged interiorly of the container
around said drain hole, said fitting further including a
threaded stem depending from said flanged seat, said fit-ting
having bore extending therethrough, a sealing ring arranged
around said threaded stem and adapted to contact the under-
surface of the container bottom, a coupling means having a
threaded bore capable of thread engagement with said stem
whereby to be capable of pressing said sealing ring against
the undersurface of said container bottom, said coupling means
being connected to a coupling assembly, said coupling
assembly terminating at a connection with a valve means,
whereby said hot water container may be drained upon opening
$aid valve means.
BRIEF DESCRIPTION OF THE DR~WINGS
The improved beverage-making device is described in
conjunction with the following figures in which like
reference numerals are used throughout to identi:Ey the same
components, wherein:
Figure 1 is a perspective view of a beverage-making
device having the improvements of the invention housed
therein;
Figure 2 is a schematic view of the entire water flow
system for the beverage-making device of Figure 1, diagram-
matically showing the tap-off hot water system, spray disk
assembly and bottom drain system;
S~5fL
Figure 3 is a sectional view of the hot water container
of the beverage-making device showing the safety thermostat
arrangement, the sensing tube for the running thermostat
system, the water coil for the tap-off hot water system, and
the bottom drain system;
: Figure 4 is a plan view of the hot water container cover
assembly, including the improved running thermostat system
associated therewith and the inlet and outlet openings for the
water coil shown in Figure 3;
Figure 5 is a front elevational view of the improved
safety thermostat arrangement as shown in Figure 3;
Figure 6 is a sectional view taken along lines 6-6 of
Figure 4 showing the locking assembly for mounting the sensing
tube o~ the running thermostat system to the container cover
and a conventional bracket used for mounting a safety
thermostat at the cover;
Figure 7 is a perspective view of the mounting bracket for
the running thermostat as shown in Figure 4;
Figure 8 is a sectional view taken along lines 8-8 of
Figure 4 showing the outlet cap and baffle used for controlling
the discharge of brewing water siphoned from the container into
a siphon tube,
Figure 9 is a sectional view of a check valve provided for
the hot water system as shown in Figure 2;
Figure 10 is another schematic view of the entire water
flow system of the beverage-making device, diagrammatically
showing an alternative embodiment for the tap-off hot water
system;
Figure 11 is a sectional view of an alternate combination
check and relief valve provided for use in the hot water system
shown in Figure 10~
Figure 12 is an exploded perspective view of the improved
spray disk assembly as shown in Figure 2;
Figure 13 is an exploded perspective view of a portion of
the bottom drain system as shown in Figure 3;
Figure 14 is a side view of an alternate looped heating
element usable in conjunction with the invention; and
Figure 15 is a front view of the heating element as shown
in Figure 14.
~259L 13S3~
DETAILED DESCRIPTION OP THE PREFERRED EMBODIMENT
Introduction:
-
Figure 1 is a perspective view of the exterior of a coffee-making
device 10 which has a generally wel]-known desi~n and inc]udes an upper
housing 11 and lower housing 12. ~ brewing chamber 13 is removably
held by a conventional slide track means 14 in position for receiving hot
water siphoned from a heated tank disposed inside lower housing 12. A
decanter, or coffee pot 15, is stationed on a armer 16 and co}lects
incoming brewed coffee from the chamber. The warmer is activated in
the usual way by a switch 17. To keep previously brewed portions of
coffee warm, the upper housing 11 inc]udes two warmers l8 and 19. A
decanter 15 is filled with coffee and is shown stationed at ~armer 18.
The coffee maker 10 may also employ an auxiliary warmer unit 16A of
conventional design, shown in phantom lines in Figure 1.
The coffee maker 10 is operated by means of a control panel 20,
which includes a main switch 211 a brewing cycle switch 22 and a ready
light 23. Thè switch 21 activates the electrical system of the coffee
maker whereby a heating element and therrnostat arrangement cause a
stored volume of water to be heated to a desired brewing temperature,
as will be hereinafter described. A ready light 23 is illuminated when
the system is ready to provide hot water for brewing coffee. At that
point, a brewing cycle may be initiated by depressing the switch 22,
whereupon the hot water is siphoned onto coffee grounds contained within
the chamber 13. l~armers 18 and 19 are operated by the switches 24
nnd 25 located near the top of the panel 20.
The control panel 20 further inc1udes a hot water îaucet 26
e~;tending outwardly therefrom, which provides menns for dispensing wflter
from the tap-off water system of the invention, as will be described below.
Figure 2 is a schematic drawing of the internal components of the
coïfee maker 10. The upper housing 11 and lower housing 12 are shown
in dashed lines. It will be understood that the electrical circuitry for
the device 10 is provided in a conventional manner, such as found in the
wiring system for l~odel Nos. 8714 and 8715 made by B]oomfield Industr;es,
Inc., Chicago, Illinois. The relationships of the various components in
the wiring scheme, including the improved safety thermostat arrangement
~2~ S~
and the running thermostat system of the invention, are intended to be
connected in the circuit in this known manner, and the circuitry therefore
forms no part of the invention.
~ 7ith reference to };i~ures 2-~, it will be seen that the cofree-
making device 10 includes a hot water container, or tank, 27 which is
initially filled with a predetermined volume of water. In the illustrative
embodiment~ the tank 27 ho]ds approximately one gallon when fi]led to
the intended ma~;mum level of about one-half inch below the top of the
container. ~Yhen the su1itch 21 is on, the temperature of the water inside
the tank 27 is monitored by an improved running thermostat system 28.
The required brewing temperature is in the rsnge of from sbout 20~ F.
to about 205 F. To facilitate heating the water, a sheathe~ electrical
heating coil 29 is arranged within the tank and is in electrical
communication with the running thermostat system 28. When the running
thermostat system 28 detects that the water temperature has fallen below
the desired range, the system c]oses A circuit and activates the heating
coil 29 until such time that proper brewing temperature is achieved within
the container 27. The ready light 23 is electrically controlled by the
running thermostat system and is not il]uminated until the heating element
is de-activated.
As best viewed in Figures 3 and 4, a cover 30 closes the open top
of the tank 27 and is hermetically sealed thereto by means of a gasket
31 disposed between the upper rim Or the tank and the peripheral lip of
the cover in a known manner. The hot water is thereby safely sealed
within the tank.
~ hen freshly brewed coffee is desired, the brewing basket, or
cllamber 13 is ]ined with fi]ter paper and then manually loaded with a
predetermined amount of ground coffee. The coffee pot 15, as shown
in Figure 1, may then be placed onto the warmer 16 in position to receive
breu ed coffee from the chamber 13. Brewing cycle button 22 is then
pushed to initiate the brewing sequence.
The water flow system for providing brewing u-ater to the chamber
13 is best understood with reference to Figure 2, wherein a u~ater in]et
pipe 32 is arranged at the bottom portion of the housing 12 and is
connected to a water supply line (not shown). The inlet pipe 32 is in
fluid communic~tion with ~ solenoid valve 33 ~ hich is oper~ted by a
~2~4~S~
.
conventional timer mesns that begins its sequence when the button 22
is activated. The timer is calibrated to open the valve 33 for the period
of time required to admit a vo]ume of water sufficient to fill the coffee
pot lS. The valve 33 includes a cleanout 34 to enable it to be backflushed
u~hen lime deposits accumuIate at the valve. The flow rate from the
valve 33 ;s control]ed by an internal flo~1 control valve 35, which in the
exemp]ary embodiment permits 0.75 gallons per minute to pass into an
inlet pipe 36. The inlet pipe 36 directs the cold water uptvardly into a
basin 37 disposed within upper housing 11. The basin 37 is formed to have
a drain sump 38 for draining incoming water into a tube 39. Tube 39
directs the water through an aperture 39' of cover 30 and terminates
thereat to open into a funnel 40. Funnel 40 is affixed to the bottom of
the cover around aperture 39'. An inlet tube 41 is connected to the
funnel 40 and extends downwardly into the container 27 to discharge the
cold ~ater near the bottom of the container. The entering cold u~ater
displaces an equal volume of hot ~vater nesr the top of the cont~iner 27
wllich flows ;nto a siphon tube 42.
~ Yith reference to Figures 4 and 8, it will be noted that a raised
annu]ar shoulder 90 projects upwardly from the cover 30 and has a central
aperture 42' into which the siphon tube 42 is attached to be in fluid
communication with the hot water. An outlet cap 91 and a baffle 92
are welded at the undersurface of the shoulder 90 in a typical construction
whereby the r;sing, displaced hot ~vater is controlled in its passage
upwardly through the aperture 42' into the siphon tube. The siphon tube
42 slopes downwardly from the top of the container and discharges the
hot water into a spray disk assemMy 43, which distributes the water over
the coftee grounds in brewing chamber 13.
Fo]lowing the timed sequence, the valve 33 is closed, and the
hcated water within the brewing chamber 13 bathes the coffee grounds
therein, whereby brewed coffee seeps from the chamber, by gravity, into
the decanter 15. It will be understood that the calibration of the timer
means will preferably be made so that the portions of ~vater sbsorbed
by the grounds and lost in the rorm of steam are taken into account in
order that the decanter is filled to the necessary level.
In the event that pressure is built up within the container 27, a
vent tube 44 is affixed to the cover 30 at the aperture 44' to communicate
~s~
interiorly of the container 27. The vent tube extends upwardly from the
cover 30 to enter the basin 37 for dischsrge thereint Accordingly, excess
wster pressure will be relieved into the basin anc~ be safely drajned back
into the container via the drain sump 38.
Since the cold inlet water decreases the tank water temperature,
the running thermostat system 28 will sctivate the electricsl heating
element 29, in the msnner mentioned above. Follo~ing s ~rewing cycle,
rapid heating sometimes occurs with certain high capacity heating
elements. If the running thermostat is faulty and sticks in the on position,
a bac~;-up safety provision is needed to de-energize the heater before
the water completely boils away and the e]ement overheats. In Figure 4,
s typical arrangement for a sa~ety thermostat 45 is shown in phantom
lines and provides a means for detecting an overheating of the cover 30.
A standard bracket 46, sho~n in solid lines, offers the mounting mesns
for the safety thermostat 95. In coffee-making devices of the type
described, the running thermostat and the safety thermostat are connected
in series ~vith the heating e]ement whereby the safety thermostat will
override the running thermostat to de-activate the heating elerment ~hen
the cover reaches these overheated temperatures. Generally safety
thermostats are manufactured to hsve sn open temperature of about 226
F. This conventional arrangement has been satisfactory for heating
e]ements of 1800 watts or less, such as the looped elements 118 and
118' shown in Figures 14 and 15, and therefore may be practiced with
the other features of the invention herein described for these lower
capacity elements. Therefore, the cover 30 is preferably provided with
a bracket 46 in the event that the coffee maker lO is provided with the
]ower capacity heating elements. However, the arrangement of the
thermostat 45 has been found to be inefricient for the higher cnpacity
e]ements which can quickly overheat the lower portions of the container
27 long before the cover 30 becomes equally hot.
Improved Safety Thermostat Arrangement:
~ Vith reference to Figures 3 and S, an improved safety thermostat
arrangement is shown for use with the high capacity hesting elements
and replaces the e~:isting techniques, sl~ch as the thermostat 9S of Figure
4. ln the preferred embodiment, the heating coil 29 is a 230 volt, 4800
~;~5~5~L
wstt, 11 loop coil. Other high capacity heating e]ements, similar to the
heating element 29, may alternatively be provided, such MS a 120 volt,
2000 watt coil having 5 loops, or a 230 volt, 3500 watt coil having 8 loops.
The top loop of the coils is connected to a conventional termina~
assembly T by a vertical section of the heating element. The bottom
]oop of the coil is connected to a conventional termina~ assembly T1 by
a vertica~ section of the e]ement. Both of the terminal assemblies T and
T' provide water tight connections with cover 30 at terminal openings
29A and 29B, as best viewed in Figures 3 and 4.
It will be observed that the loops of the coil 29 extend annu]ar]y
near the side of the container 27. At these locations rapid increase in
temperature can occur. In solution of the problems ~-ith ~prior art systems,
there is provided à manually resettable thermostat 47 perferably mounted ---
adjacent the container 27 at or below the mid-point thereof and generally
close to the heating coil. The thermostat 47 has an e~posed bi-metal
disk 48 disposed against the side of the container. In the exemplary
embodirnent, the thermostat 47 is an Essex Internàtional Controls Division
thermostat Model No. ~04 58 having an open temperature of 226 ~. +
9 F. The thermostat 47 includes terminals 49 and 50 which are of the
spade-type variety, whereby the thermostat 47 is wired to be in series
with the running thermostat system 28. The thermostat 47 includes a
mounting plate S1 affixed to a housing 52 of the bi-metal disk 48. The
plate 51 extends transverse]y to the terminals 49 and 50 and has
side~vardly-open notches 53 and 54 at opposite sides thereof. A
cooperative bracket 55 is disclosed for the positioning of the thermostst
47 at the desired location along the tank 27. The bracket 55 is preferably
rnflde of stain]ess spring steel and has a mounting foot 56 and an upward]y
e~:tcnding 1Ong arm 57. The foot 56 is mechanically fastened by scre~vs
S to the bottom of the housing 12 and is made whereby to form an ang]e
of greater than 90~ with arm 57 before attachment in the coffee maker.
The affi~;ation of the foot 56 to housing 12 disposes the arm 57 At right
ang]es to the foot 56 and thus arm 57 is spring biased to-vard the container
27 in order to urge the therrnostat 47 ngAinst the container. A mechanical
fastening of the thermostat 47 to the bracket 55 is envisioned wherein
the upper end of the arm 57 is cut-out to form a seat 58 intermediate
a pair of upsthnding side ears 59 and 60. The ears 59 and 60 include
13
... .
holes which, as w~uld be understood, ar~ spaced to align with the notciles
53 and 54 so that screw fasteners S' may secure the mounting pla~e 51 to
the b~acket 55.
Preferably, the thermostat 47 is positioned so that the bi-metal
disk 98 contacts the side of tank 27 just slightly above the upper loop
of the heating coil 29 where rising heat from the coil will create the
hottest spot. If temperatures exceeding the thermostat capacity are
created st the bi-metal disk 48, as might occur when a defective or
stuck running thermostat fails to switch off and continues to energize
the heating element until finally all the water evaporates, the thermostat
opens the circuit to de-activate the heater 29. The thermostat 47 is
provided with a manual reset button 62, which requires the operator to
make the necessary reset once the heater has been shut down. A manually
resettable thermostat is preferable for this safety system, but
fllternatively, a self-resetting thermostat may a]so be used. Access to
the reset button 62 is provided by a removably-capped peek hole means
61 located in positional correspondence with the thermostat 47 along the
front face of the housing 12, as shown in Figure 1. A smflll screwdriver,
for example, may be ~Ised to push the button 62 and reset the thermostat
for subsequent use.
Improved RunninF Thermostat System.
The running thermostat system 28, which heretofore has been
generally discussed with regard to activating and de-activating the heating
element 29, will now be described in greater detail with reference made
to Figures 3, 4, 6 and 7. System 28 is fln impro~ement over previously
known arrangements, particularly because the mean temperature of the
entire water volume is sensed. Also, temperature variation is sensed
within a very narrow range. These are significant advances in the
beverage-making art because the device 10 is thereby rendered
considerably more efficient by only operating the heating element when
necessary.
The improved running thermostat system 28 inc]udes a thermostat
63 located at the cover 30. The thermostat 63 has an adjustable control
shaft 64 that enables the thermostat setting, and thereby the brewing
water temperflture, to be varied. Preferably, the thermostat 63 has the
14
s~
operating capacity of a ROBERl`S~AW Controls Company thermostat No.
K-944-12, or equivalent. Other suitable devices will be apparent to those
skil]ed in the art. The thermostat 63 is affixed wi th a mounting flange
65 having a pair of engageable holes 66 and 67. A cooperative mounting
bracket 68, best shown in Figures 4 and 7, supports the mounting î]ange
65, and thereby the thermostat 63, at cover 30. The bracket 68 comprises
a lower plate 69 integrally formed with a vertical p]atè 70, which inc]udes
a vertical slot .71, a horizontal s]ot 72, and a central, upwardly open
notch 73. The slots 71 and 72 correspond to the spacing of the ho]es 65
nnd 67 of the mounting flange 65. Screw fasteners 74 and 75 are provided
to be received through the slots 71 and 72 and thereafter engaged within
the holes 66 and 67 whereby to releasably hold the thermostat on the
bracket. In this arrangement, the thermostat 63 is easily removab]e from
the bracket 68 by partially unthreading the screws and thereafter simply
moving the thermostat first upwardly to disengage the fastener 74 from
the slot 71, and thereafter sidewardly to remove the fastener 75 from
the slot 72. This rernovability is a significant advantage for repair
personnel since, unlike previous devices, these threaded fasteners need
not be rernoved and therefore cannot become accidentally dropped within
the housing of the coffee-making device during repair.
A short capillary tube 76 associates with the thermostat 63 in a
conventional manner. However, the capillary tube 76 does not extend
downwardly into the container ~7 to meet a bulb end, such as found in
the prior art. Instead, a unique elongate and self-supporting sensing tube
77, best vie'wed in Figures 3 and 6, extends downwardly from the cover.
The sensing tube 77 is joined to the capillary tube 76 interiorly of a
fastening assembly 78, shown in the sectional view of ~igure 6. The
sensing tube 77 offers a great advance over the existing thermostat
systems inasmuch as no guide sleeve is nceded. Further, the sensing
tube need not be attached to the heating coil, which is customary with
known guide sleeve systems in order for the bulb to be maintained in
the proper vertical orientation at a specified depth within the hot ~ater
container.
The sensing tube 77 is hollow and is preferably made of stainless
steel. A conventional oil is contained within the tube 77 and is in f~uid
communication with the capillary tube 76 es would be clear. Sensing
~%~ 5~
tube 77 extends do~nwardly within the coi]s of the e~ement 29 and
lerrninates generally near the bottom thereof in a crimped end 79. The
tube 77 thereby extends ior substantially the full height of the container
27 and renders the system 28 capable of detecting the mean temperature
of substantially the entire volume of water within the tank. Existing
capillary buib devices usually have an outer diameter of greater than
0.30 inches. Thus, a g~lide sleeve of greater diameter is required to
surround the bulb end. In preferred form~ the sensing tube 77 has an
outside diameter less than 0.30 inches and therefore occupies a smaller
space. It has been found that this thinner construction allows the oil
therein to be quickly sensitive to the temperature changes whereby the
temperature detected at the thermostat 63 is closely reflective of the
temperature f]uctuations within the tank. As a resu]t, the system 28 is
capable of responding to temperature chflnge in a range of from about
2 to 3 F. spread and at least before a G F. change has occurred.
Existing systems are less precise and are responsive to spreads of about
6 to 8 F., or more.
Reference is now made to the locking means 78 shown in the
sectional view of Figure 6. It will be seen that the cflpillary tube 76
is so]dered to a tapering upper end of the sensing tube 77 generally
denoted by reference numeral 80. A fema]e fitting 81 is ~eld-connected
within and around an aperture 82 e~:tending through the cover 30. The
fitting 81 inc]udes a centrally threaded bore 83 which is thread engageable
with a lock nut 84. The lock nut 84 is hol]ow whereby to perrnit the
capi]]ary tube to pass therethrough and be joined with the tube 77 at
the so]der connection 80. At its ]ower end, the bore 83 includes an
inwardly extending annular shoulder 85 forming a bearing seat within the
fitting 81. A collar 86 is so]dered around the upper end of the sensing
tube 77 generally below the solder connection 80 and includes a peripheral
shoulder 87. Between the peripheral shoulder 87 and the annular shoulder
85, a water tight sealing means is provided by a rubber gasket 88 and
meta] ~-asher 89, which are compressed by the ]ock nut 84 as it threads
downY:ardly into engagement with the bore 83. Lock nut 84 a]so securely
fastens the collar 87 within the fitting 81 and thereby fixes the sensing
tube 77 in the orientation illustrated in Figure 3.
~Z5~
-
It will be appreciated that the running thermostat system 28 is
comp1etely disengageable from the cover 30 without the removal or
disturbance of any other components. Specifically, the thermostat 63
can be disengaged from the bracket 68 as explained, and by untightening
the lock nut 84, the sensing tube, with the capillary 76 attached thereto,
rnay be drawn upwardly out of the aperture 82 in a facile manner. ~Yhen
the need to rep]ace the thermostat 63 arises, repair is therefore expedited
and maintenance costs are reduced. It is contemplated that replacement
of the thermostat 63 will not be required as often as with existing
systems due to the capability of system 28 to sense the mean temperature
Or the water within a narrow temperature spread. By quickly reacting
to the tvater temperature changes, the heater is activated before the
temperature drops no more than 6 F. be]ow the usually desired brev~ing
temperature o 205~ F. Furthermore, the heating element will not remain
activated as long, since as the temperature is raised, the system 28 will
react to de-activate the element at no greater than about 6 F. above
the brewing temperature. This eff;ciency is critical with high capacity
heaters because they tend to deteriorate much more quick~y than the
]ower capacity elements. lt will also be clear that the hot water is
al most always made available at the proper temperature for making
coffee. The capability of the system 28 to minimize this activation time
and keep the water at the desired temperature are significant benefits
of the invention.
Tap Off Hot ~Yater S~1stem
The invention further provides a ta~off hot water system which
does not borrow from the water content within the container 27 and
requires no float switch means. With reference to Figures 2, 3 and 9,
it will be observed that the ta~off hot water system is generally denoted
by reference numeral 93. A significant feature of the system 93 is that
it taps cold vJster from the inlet pipe 32 by means of a T-fitting 94
located upstream of the inlet va]ve 33. A check valve 95 is connected
to the T-fitting 94 by a suitab]e connecting pipe means whereby a
minirnum water pressure is required before water is introduced into the
systern. The check valve 95 has a conventional construction, as shown
by the sectional view thereof in Figure 9, w herein a spring biased va]ve
~5~ 015~
96 controls the passage of water from an inlet chamber 97 into an outlet
chamber 98. In the preferred embodiment~ the check valve 9S requires
2 p.s.i. of pressure to open.
~ Yater conveyed through the check valve passes straight through a
T-fitting 99 into a tube 100 which directs the cold water into a
cornpression fitting 101 sealingly arranged within an aperture 101' at the
cover 30.
The important characteri~ing feature of the tap-off hot wster
system is the arrangement of a water coil 102 within the container 27.
The water coil lû2, in preferred form, is a hollow stainless steel tubing
having about at ]east an 8 ounce capacity. The coil 102 is concentrically
arranged above heating element 29 and spaced below the cover 30 as
shown in ~igure 3. Coil 102 includes an upright cold water receiving
tube 103 communicating with the lowest loop of the coil and a shorter
upright hot water outlet tube 104 communicating with the topmost loop
of the coil. The tube 103 is connected to the compression fitting 101
below the cover 30 to be in fluid communication with the tube 100.
Cold water entering from the tube 100 thereby circulates through the
coil 102 and is quickly heated due to the constantly maintained
temperature of the water resulting from the on and off activation of
the heating elen~ent 29, as described above.
It will be observed that in the preferred embodiment the water
coil 102 includes 14 loops arranged in a helical formation wherein adjacent
]oops are in contact. No need for additional heating of the coil is
required since it is p]aced generally at the upper half of the container
27 and is continuously surrounded by hotter rising water circu]ating past
the individual ]oops. A second compression fitting lOS is sealingly arranged
within an aperture 105' of the cover 30 and is connected to the outlet
tube 104 below the cover 30 and to a hot ~-ater discharge tube 106 above
the cover. The discharge tube 106 conveys hot water outwardly Or the
container 27 to pass through a speed valve 107 associated therea]ong.
The speed va]ve 107 is manually operable to permit varyin~ the water
pressure therethrough, such as when there are changes in the water supply
pressure entering the inlet pipe 32. The out]et tube 106 extends genera]ly
horizontal]y toward the control panel 20 and is connected thereat with
a ]ever-action faucet 26, as best viewed in Figures 1 and 2. The faucet
18
~;~S~05~
;
26 is preferably a conventionsl 100 p.s.i. to lS0 p.s.i. fa~cet, well known
to those skilled in this art.
~ t'hen hot water is needed for making tea9 instant soup, hot cocoa,
etc., the faucet 26 is manually opened and cold water flows inwardly
from the inlet 32 through the inlet tube 100 into the coil 102 to force
hot water in the coil to be pressured outwardly thereof into the tube
106 and dispensed via the faucet 26. Due to the continuous heat
transferred to the coil from the hot water in the container and the
unique he]ical coil arrangernent, by the time the cold water entering
from the inlet tube 100 reaches the outlet tube 104, it is RS substantially
as hot as the brewing ~- ater within the container 27. Thus, a constant
source of hot water is readily available without the need to borrow f'rom
the contents of container 27. It will be ~ppreciated that there is no
need to provide any noat limit switches which are otherwise required in
conventional hot water systems that simply drain the water tank to obtain
hot water.
Since the water heated within the coil 102 will naturally expand
and increase the pressure in the system 93, the faucet 26 may e~;perience
pressures in excess of its capacity and leak. Relief for this pressure is
provided by a pressure chamber 108, which is connected to the transverse
stem of the T-fitting 99 by a standard elbow 109, shown in Figure 2.
Any excess water pressure caused by expansion in the coil 102 ~Yill
therefore be relieved through the tube 100 into the chamber 108 and
prevent leakage at the faucet 269 or for that matter, at any other
components within system 93.
The plscement of the pressure chamber 108 is envisioned to be
vertically within the lower housing 12 of the coffee maker 10 generally
at a corner thereof and spaced from the container 27. In conventional
housing designs, the standard box-shaped lower housing affords roorn at
either of its rearward corners which provide sufficient space for stationing
the pressure chamber 108.
An alternate embodiment of a pressure relief means for the system
93 is disclosed in Figure 10. The same reference numerals ~re used to
denote the system 93 in both Figures 2 and lO, with the e~ception that
in Figure 10 the inlet tube comprises two sections, denoted lOOA and
100~, and it ill be observed that these A and B sections are created by
~2S~5~l
r~positioning the T-fitting 99. In this alternative, the pressure chamber
108 is deleted nnd the T-fitting 99 is re-located upwardly along the inlet
tube section lOOA generally adjacent the cover 30. The stem of the T-
fitting is oriented in the opposite direction with respect to that shown
in Figure 2. In this embodiment, the stem of the T-fitting is engaged
with the inlet tube section 100B, which directs the water flow into the
coil 102 as explained above. The other arm of the T fitting is connected
to a standard pressure relief valve 110. The relief valve 110 preferably
has an open pressure capacity of about 100 p.s.i. to 110 p.s.i., so that it
will open at a pressure level below the pressure capacity of the faucet
26, as would be clear.
Downstream of the pressure relief valve 110 a suitab~e elbow 111
connects the valve to an overflow tube 112. The overflow tube 112
extends to pASS through the wall of the basin 37 for discharge of overf]ow
water into the basin. Thus, the system 93 ~ ill be relieved of excessive
pressure by discharging it into the container 27 via the drain sump 38 in
a similar manner to the action of the vent tube 4~.
Figure 11 shows a twin valve assembly 113 alternatively usable in
the embodiment illustrated in Figure 10. The twin valve assembly 113
inc]udes, in a single housing, a check valve 114, a pressure relief valve
115, a T-fitting 116 and an elbow 117, which respectively replace the
check valve 95, the pressure relief valve 110, the T-fitting 99 and the
elbow 111, shown in Figure 10. The check valve 114 and the pressure
relief valve 115 are provided to open at the same respective levels of
water pressure as described for the check valve 95 and the pressure
relief valve 110. Thus, incoming water from the inlet tube section lOOA
is directed into the section lOOB through the T-fitting 116. ~hen excess
pressure is experienced by the system, the relief valve 115 opens and
directs water through the elbow 117 into the overflow tube 112. It is
envisioned that the twin valve assembly 113 would be arranged u~ithin
the system 93 in substantially the same location as the T-fitting 99 shown
in ~igure 10.
In preferred form, the inlet and outlet pipe means for the system
93 comprises standard on~quarter inch copper tubing but, of course, they
rnay have a ]arger or smaller size as needed.
:~L2~ S~l
Y~'hile the hot water system 93 has been described in conjunction
with a beversge-making device 10 heving a high capacity heating coil 29,
it should be apparent that the unique design for the water coil 102
permits the system to be equally suited for use in devices having a
variety of heater arrangements. For example, the system 93 may be
provided in combination with lower capacity heaters, such as the e]ements
118 and 118' ~phantom lines) shown in Figures 14 and 15. The e]ements
118 and 118' each have a pair of terminals t and t' which are capable
of being secured to a tank cover in substantially the same manner as
the terminals T and T' of the heating coil 29. The element 118 is a 100-
120 vo]t single loop heater having a 1300-1500 watt capacity, particularly
useful for standard electrical circuits in the United States7 Canada and
Japan. The e]ement 118' is 8 220-240 volt single loop heater having an
1800 watt capacity for use in the standard electrical circuit systems
found in Europe. Each heating element is formed to have a narrow
e]ongate J-shape ~Figure 14) which is adapted to be arranged within a
hot water tank generally at the central long axis thereof. It will be
understood that the coil 102 is capable of being disposed within the tank
to circumscribe either heater element 118 or 118' whereby the system
93 operates in the same way as explained above.
Clearly, the coil lQ2 may be provided to have a different diameter
and number of looped coils so to be approprintely sized for various
cylindrical tanl~ dimensions. A wide variety of loop shapes are also
intended to fall within the scope of the invention. It will be apparent
that the water coil is not limited to a helicAI configuration and may be
suitably shaped for use in contAiners that are polygonal in cross-section.
Improved Spray Disk As mbly:
With reference to Figures 2 and 12, the improved spray disk
assembly of the invention is shown and is general]y denoted by reference
numeral 43, previously mentioned above. Figure 12 is an exploded
perspective view of the assembly 43, which eomprises a mounting collar
119 associating with a flexible gasket 120 and a spray disk 121. The
mountin~ collar 119 is affixed at an undersur~ace 122 of the upper housing
11 around an opening 123 therethrough, which communicates with the
siphon tube 42. The col]ar 119 comprises a circu]ar top p]ate 124 having
~5~
8 centr~l opening 125 arranged at the opening 123. In the exem- v
embodiment, the top plate 124 is welded to the undersurface 122 and has
a depending peripheral side wall 125 formed therewith. The side wsU
125 includes a pair of dismetrically opposed bayonet slots 126 which
do~ nwardly open a$ 127 and upwardly terminate in hori~ontal portions
128. The gasket 120 is provided with an outside cliameter substantially
equal to the inside diameter of side wall 125 and has a height s]ightly
less than the height of the side wall and sufficient to extend from the
top plate 124 downwardly to meet the horizontal portions 128.
In the past, a siphon tube simp]y discharged onto a spray disk
which was resiliently held by a mounting collar. l`he improved sssembly
43 provides rigid locking and tight sealing between the mounting collar
119 and the disk 121 whereby leakage about the periphery of the disk 121
is avoided. The disk 121 is best described as a generally circular plste
h~ving a diameter sized to snugly fit within the side wall 125 and includes
a pair of oppositely extending radisl tongues 128. The tongues 128 include
a flat section 129 adjacènt the disk edge and terminate out~ard]y in U-
shaped portions 130. By grasping the U-shaped portions 130, the f]at
sections 129 are engageable at the bayonet slots 126 by moving the disk
121 upwardly to dispose the sections 129 within the openings 127.
Thereafter, the disk is rotated in a clock~ise direction to securely ]odge
the sections 129 within the horizontsl portions 128. Thereby, the gasket
120 is sealed against the top 124 and the disk 121 whereby to prevent
]eakage between the disk and the side wall 125.
The disk 121 is provided with a series of orifices 131 which are
flrranged to form a central imperforate portion 132. lYater, discharging
from the container 27 through the siphon tube 42, drips onto this
imperforate portion 131 and flows outwardly therefrom to randomly drip
through the orifices 131. As previously described, the f;low control valve
35 preferably limits the inlet rate of water flow to the tank 27 to about
0.75 gallons per minute. As a result, water is siphoned from the tank 27
in a moderate pace whereby the ~ater pressure emitted from the siphon
tube ~5 will be measured to be less than one inch of mercury.
The tight seal created by the locking engagement of the tongues
128 ~dthin the bayonet s]ots 126 assures thst the ~.~ater is directed through
the orifices and is prevented from leaking around the edges of disk 121.
22
~l2~
~ Vhen cleaning is required due to the accumulation of lime, or
other sediments, the operator can easily disconnect the disk by grasping
the U-shaped portions 13û and then twisting the disk 121 counterclock~ise
to disenga~e the sections 129 from the s]ots 128. This locking feature
of the assemb]y 43 will thereby be appreciated as providing a rigid, but
removsble, securement between the disk 121 and the mounting collar
12û, while completely eliminating any reliance upon resilient connections
which have proven unsuccessful heretofore.
Drain Systeln:
A UniQUe drain system 133 is provided for emptying the hot water
container of the beverage-mPking device 10 and is best viewed with
reference to Figures 3 and 13. The drain system 133 associates with a
central drain hole 134 at the bottom 135 of the container 27. The
systern 133 includes a drain fitting 136 which has an open bore 137 for
receiv;ng drainage therethrough and an upper annular flanged seat 138
residing interiorly of the container 27. A threaded stem 139 is integrally
formed with the seat 138 and extends downwardly through the drain hole
134. The bottom of the seat 138 is beveled at 140 and the container
bottom 135 includes a cooperatively depressed annular bevel 140' around
the drain hole 134 whereby the seat 138 can be flushly and tightly sealed
at the boLtom 135.
A coupling means comprising a female elbow 141 is provided for
engagement with the external threading of the fitting 136. In order for
the elbow 141 to threadably engage the fitting 136, the drain hole 134
nnd ~he stem 139 have flat sides 142 and 143, respectively. Thereby,
the bottom 135 is cooperative to act like a wrench and prevent the
fitting 136 from rotating in order to facilitate the engagement, or
disengagement, of the elbow 141.
The elbow 141 includes an upper annular seat 144 for the
accommodation of an O-ring 145 therein. Vpon thread engaging the
elbow 141 to the drain fitting 136, the O-ring 145 is compressed to seal
agsinst the undersurface of the annual bevel 140' to prevent ]eakage
therearound. A standard male coupling 146 engages the outlet side of
the elbow 141, and at its opposite end engages with a reducer coupling
147. A third coupling 148 engages the other side of the reducer coupling
23
.. ... . ... ______ ........... .......
~254~5~
147. Lastly, a rnanually operable drain cock 149 engages the outlet end
of the coupling 148. The coupling assembly 146-148 is of a sufficient
length whereby to dispose a drain cock 149 adjacent the housing 12. An
access cut-out (not shown) is provided through lhe housing so that the
drain cock can be easily reached when needed. In Figure 3, a hose 150,
shown in phantorn, is connected to the drsin cock in order to drain the
water from the tank 27 into a sink, pail, etc.
In conventional beverage-making devices, a removable rear pane]
is provided so that access to the internal components can be obtained
for maintenance and repair. By the provision of the drain system 133,
it will be clearly understood that the elbow 141, the coupling assembly
146-148 and the drain cock 149 are fully removable as a unit by simply
disconnecting the elbow 141 from the drain fitting 136. Thus, not only
can the system 133 be repaired, if necessary, but other surrounding
cornponents within the device 10 may be easily reached by simply
removing, and later easily replacing, the system.
The system 133 requires no welded connection with the tank 27,
and therefore the corrosion problems inherent in previously kno\~n welded
fittings is totally e]iminated.
AÇH~E~ MENTS
An improved beverage-making device has been disclosed which
safely and efficiently controls the heating element for tlle hot water
container by the provisions of an improved safety thermostat arrangement
nnd an improved running thermostat system. Additionally, the invention
includes a tap-off hot water system which dispenses hot water without
borrowing from the hot water container. Further, the invention achieves
the goal of providing an improved spray disk assembly that offers a
tightly sealing locking means for Ihe disk whereby the brewing water ;s
evenly and moderately distributed over all the coffee grounds contained
in the brewing chamber. Moreover, the invention provides for the
compIete drf~ining ~f the hot water tank by means of a unique bottom
drain system removsbly engaged at the bottom of the container in a
tightly sealing non-corrosive connection.
24
~2S4eE;I 5~
While the foregoing description of the invention has been directed
toward a preferred embodiment therefor, it will be apparent to others
that vari~us modifications and alternative embodiments fall within the
scope of this disclosure and the claims appended hereto.