U.S. patent number 3,916,963 [Application Number 05/478,895] was granted by the patent office on 1975-11-04 for automatic drink dispenser.
This patent grant is currently assigned to Rolar, Inc.. Invention is credited to Lawrence D. McIntosh.
United States Patent |
3,916,963 |
McIntosh |
November 4, 1975 |
**Please see images for:
( Certificate of Correction ) ** |
Automatic drink dispenser
Abstract
An automatic drink dispenser for filling cups with liquid when
placed in receiving position on a support platform and including a
solenoid controlled valve for dispensing liquid into said cups
comprises at least one contact member positioned to make contact
with the liquid dispensed into said cup in said receiving position
when the liquid reaches a predetermined level therein and means
electrically interconnecting said contact member and said solenoid
control valve for controlling said valve to stop the flow of liquid
when the liquid reaches a predetermined level in the cup.
Inventors: |
McIntosh; Lawrence D. (Chicago,
IL) |
Assignee: |
Rolar, Inc. (Arlington Heights,
IL)
|
Family
ID: |
23901812 |
Appl.
No.: |
05/478,895 |
Filed: |
June 13, 1974 |
Current U.S.
Class: |
141/198; 141/95;
141/361; 141/367 |
Current CPC
Class: |
B67D
3/00 (20130101) |
Current International
Class: |
B67D
3/00 (20060101); B65B 003/26 () |
Field of
Search: |
;141/94,95,96,100,105,193,198,250,283,267,351-362,367,373,378,206,208,209,218 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Bell, Jr.; Houston S.
Attorney, Agent or Firm: Mason, Kolehmainen, Rathburn &
Wyss
Claims
What is claimed as new and desired to be secured by Letters Patent
of the United States is:
1. In combination with a soft drink dispenser of the type having a
solenoid controlled dispensing valve for discharging liquid into a
cup placed in a receiving position, a control unit comprising probe
means for making contact with the liquid dispensed into a cup
placed in said receiving position when said liquid reaches a
predetermined level in said cup, first means actuated by said probe
means upon movement of a cup into said receiving position for
actuating said solenoid controlled dispensing valve of said
dispenser to discharge liquid into said cup and second means
actuated by the contact of said liquid in said cup with said probe
means when said liquid reaches said predetermined level for
actuating said solenoid controlled valve of said dispenser to shut
off the discharge of liquid.
2. The apparatus of claim 1 wherein said probe means comprises a
pair of spaced apart probes having lower end portions for
contacting said liquid in said cup and pivotally supported above
said cup for pivotal movement upon engagement by a cup moved
transversely thereof into said receiving position.
3. The apparatus of claim 2 wherein said probes hang downwardly in
a normal position when not engaged with a cup and are pivotally
moved to a switch activating position by engagement of said lower
end portions thereof with a cup moved transversely against said
probes.
4. The apparatus of claim 3 wherein said first means includes
switch means activated by the pivotal movement of said probes from
said normal position to said activating position for initiating the
discharge of liquid into said cup placed in said receiving
position.
5. The apparatus of claim 3 wherein said lower end portions of said
probes are formed in an S-shape with a lower leg for contact with
the liquid in a cup for one height and a curved segment
interconnecting said lower leg with an upper portion thereof for
contact with the liquid in a cup of greater height at a higher
level.
6. The apparatus of claim 4 including an actuator connected with an
upper portion of said probes eccentric of the point of pivotal
support thereof for engaging said switch means to operate the same
when said probes are moved to said activating position.
7. An automatic dispenser for filling cups with liquid comprising
means for supporting said cups in position to receive said liquid,
a liquid dispenser including a nozzle spaced above said cup
supporting means and including a solenoid controlled valve for
controlling the dispensing of liquid into a cup placed in said
receiving position, at least one contact member positioned to make
electrical contact with the liquid dispensed into a cup in said
receiving position when said liquid reaches a predetermined level,
means activated by the placement of a cup in receiving position on
said supporting means for actuating said solenoid controlled valve
to dispense liquid into said cup, and control circuit means
electrically interconnecting said contact member and said solenoid
controlled valve for actuating said valve to stop the dispensing of
liquid into a cup in said receiving position when the liquid
attains said predetermined level in said cup for making electrical
contact with said contact member.
8. The dispenser of claim 7 including a pair of spaced apart
contact members for making contact with said liquid dispensed into
said cup in said receiving position whereby electrical current is
carried through said liquid between said members.
9. The dispenser of claim 7 wherein said control circuit means
includes switch means for initiating the dispensing of liquid and
mechanically actuated by said contact member when a cup is moved
into contact therewith during placement in said receiving
position.
10. The dispenser of claim 8 wherein each of said contact members
include first and second contact areas spaced at different levels
for making contact with the liquid adjacent said different levels
when contained in cups of different capacity.
11. An automatic control system for installation on a liquid
dispenser of the type having a solenoid controlled dispensing valve
for discharging liquid into a cup placed in a receiving position on
a support member, said system including a control circuit
comprising probe means attachable on said dispenser for making
contact with the liquid dispensed into a cup placed in said
receiving position when said liquid reaches a predetermined level
in said cup, first means mechanically actuated by said probe means
upon movement of a cup into said receiving position for
electrically controlling said solenoid controlled dispensing valve
of said dispenser to discharge liquid into said cup and second
means electrically actuated by the contact of said liquid in said
cup with said probe means when said liquid reaches said
predetermined level for controlling said solenoid controlled valve
of said dispenser to shut off the discharge of liquid.
12. The apparatus of claim 11 wherein said probe means comprises a
support bracket removable attached to said dispenser and a pair of
spaced apart probes having lower end portions for contacting said
liquid in said cup and pivotally supported on said bracket above
said cup for pivotal movement from a first position to a second
position upon engagement by a cup moved transversely of said probes
into said receiving position on the support member of said
dispenser.
13. The apparatus of claim 13 wherein said probes hang freely
downwardly in said first position while not engaged with a cup and
are pivotally moved to said second position by mechanical
engagement of lower end portions of said probes with a cup moved
transversely against said probes into said receiving position on
said support member of said dispenser.
14. The apparatus of claim 13 wherein said first means includes
switch means activated by the pivotal movement of said probes from
said first position to said second position for initiating the
discharge of liquid into said cup placed in said receiving
position.
15. The apparatus of claim 13 wherein said lower end portions of
said probes are formed in an S-shape with a lower leg for contact
with the liquid in a cup of one height and a curved segment
interconnecting said lower leg with an upper portion thereof for
contact with the liquid in a cup of greater height at a higher
level.
16. The apparatus of claim 14 including an actuator connected with
an upper portion of said probes eccentric of the point of pivotal
support thereof for engaging said switch means to operate the same
when said probes are moved to said activating position.
17. The apparatus of claim 12 wherein said probes are detachably
supported from said support bracket, said support bracket including
means for securing the same to said dispenser at a selected level
in a range of levels above said support member of said dispenser
for accommodating cups of different heights.
18. The apparatus of claim 11 wherein said control system includes
a housing detachably mounted on said dispenser and circuit means
connectable with said solenoid controlled valve of said dispenser
for push button control of the same to start and stop the
dispensing of liquid into a cup placed on said support
platform.
19. Apparatus for automatically controlling the flow of liquid
dispensed through a solenoid controlled valve into a cup placed in
a receiving position, said apparatus including first means
activated by the placement of said cup in said receiving position
for initiating the flow of liquid dispensed through said valve and
second means including a pair of contact members positioned to
establish a path for electrical current therebetween through the
liquid dispensed into said cup in receiving position when said
liquid reaches a predetermined level in said cup for activating
said valve to shut off the flow of liquid therethrough.
20. The apparatus of claim 19 wherein said contact members include
lower contact areas adapted to make electrical contact with said
liquid reaching said predetermined level in said cup and upper
contact areas spaced upwardly of said lower areas for making
electrical contact with the liquid in a taller cup placed in
receiving position when said liquid reaches a second level spaced
above said predetermined level.
21. The apparatus of claim 20 wherein said lower contact areas of
said contact members are offset horizontally of said upper contact
areas to clear the interior of a taller cup placed in receiving
position.
22. The apparatus of claim 21 wherein said lower and upper contact
areas of each contact member are formed of a continuous
electrically conductive probe in a substantially S-shaped
configuration.
23. The apparatus of claim 19 wherein said means for initiating the
flow of liquid comprises a depending lever pivotally supported for
actuating a switch when a cup is placed in said receiving position,
said control apparatus comprising means for detachably supporting
said contact members from said lever for making contact with the
liquid dispensed into said cup.
24. The apparatus of claim 23 wherein said means for detachably
supporting said contact members is adjustably positioned on said
lever for adjusting said predetermined level.
25. The apparatus of claim 23 wherein said contact members are
detachably supported from said supporting means.
26. The apparatus of claim 19 further comprising a relay having a
relay coil and normally closed contacts connected in circuit with
said solenoid controlled valve, means connected to said relay coil
for energizing said coil, means for interrupting the energization
of said relay coil in response to the operation of said cup
placement activated means, and means responsive to said electrical
contact through said liquid for re-energizing said relay coil.
27. The apparatus of claim 26 wherein said relay coil energizing
means includes a controlled rectifier having main electrodes
connected in series with said relay coil and a control electrode,
said interrupting means includes switch means activated by said cup
placement activated means connected in circuit with said controlled
rectifier for interrupting the flow of current through said
controlled rectifier upon activation thereof, and said electrical
contact responsive means includes transistor means electrically
coupled to said contact members and said control electrode, said
transistor means being responsive to electrical contact through
said liquid for rendering said controlled rectifier conductive.
28. The apparatus of claim 27 further including second manually
operable means for interrupting the flow of current through said
controlled rectifier, and manually operable switch means for
rendering said controlled rectifier conductive.
Description
The present invention relates to an automatic dispenser for filling
cups or other receptacles with liquid such as soft drinks, coffee
and the like and more particularly, relates to an automatic
dispenser system of the type wherein once a dispensing cycle is
initiated, flow is continued until the liquid reaches a
predetermined level in a receptacle or cup.
Many beverage and liquid dispensing devices are available today for
dispensing carbonated beverages, juices, coffee, iced tea and other
liquids into waiting containers or cups placed in a receiving
position. These prior art dispensers generally include a support
platform having grating for draining excess liquid and supporting
the cups or receptacles while they are being filled. The liquid is
dispensed from a control head spaced upwardly above the support
platform and containing one or more solenoid controlled valves for
controlling the flow of fluid during a dispensing operation. In
many carbonated beverage dispensing units, a pair of solenoid
controlled valves are utilized, one for controlling the flow of
syrup and another for controlling the flow of carbonated water.
These solenoid valves are activated by a mechanical lever which is
depressed or pivoted by contact with a cup placed in receiving
position. The lever activates a microswitch used for energizing the
solenoid windings to open the dispensing valves to dispose liquid
into the receiving position. The flow of liquid continues until
such time as the cup is manually removed or pulled away from
contact with the mechanical lever.
In the fast food industry in particular, there has developed a
great need for an automatic dispenser which will fill cups to a
predetermined level and then shut off the flow automatically to
prevent underfilling or the messy spillage and waste resulting from
overfilling cups. Several different types of systems have been
tried, however, these systems suffer from numerous drawbacks. One
such system uses a time control approach and is ineffective because
of different flow rates and pressures encountered and because of
different amounts of ice placed in the awaiting cups. Different
sizes of cups also present difficulties for a time controlled
dispensing cycle. Another system has been tried wherein a metered
volume of liquid is dispensed and this system suffers from the
drawback that there is no uniformity in the amount or density of
ice placed in the awaiting cups (usually a manual operation) and
hence a fixed and metered volume of liquid is sometimes less than
required to fill a container or in other instances, more than
required and causes overfilling and spillage.
The present invention provides an automatic control system for a
beverage dispenser which is foolproof in operation and which
eliminates the foregoing problems encountered with prior art
devices.
It is an object of the present invention to provide a new and
improved automatic liquid dispenser for dispensing liquids into
receptacles.
It is another object of the invention to provide an automatic
liquid dispenser which automatically shuts off the flow of liquid
into a cup when the liquid reaches a predetermined level.
It is another object of the present invention to provide a new and
improved automatic liquid dispenser which provides for easy and
repeated filling of cups or receptacles to a predetermined fill
level without requiring operator attention.
Another object of the present invention is to provide a new and
improved automatic liquid dispenser which is operable to handle
several different fill heights or levels for cups or receptacles of
different sizes.
Another object of the present invention is to provide a new and
improved automatic liquid dispenser which is reliable in operation,
easy to clean and sanitize and which requires little or no operator
skill or attention during operation.
Another object of the invention is to provide a new and improved
automatic liquid dispenser system capable of both manual or
automatic operation.
Another object of the present invention is to provide a new and
improved automatic liquid dispenser in accordance with the
foregoing object which can be manually operated to start or stop
the dispensing of liquid by means of conveniently located push
buttons.
It is another object of the invention to provide a new and improved
automatic liquid dispenser control system which is compatible with
and capable of being easily installed for use with presently
existing mechanically actuated dispensers.
Another object of the present invention is to provide a new and
improved automatic liquid dispenser in accordance with the
foregoing object which utilizes the mechanical lever of an existing
device for initiating a dispensing cycle and provides electrical
control for shutting off the flow when a desired fill level is
reached.
Another object of the present invention is to provide a new and
improved automatic liquid dispenser system particularly suitable
for rapid installation and integration with presently existing soft
drink dispensing devices, which system is relatively low in cost,
easy to install and assemble and extremely reliable and foolproof
in operation.
Another object of the present invention is to provide a new and
improved automatic liquid dispenser system in accordance with the
foregoing object which system can be easily turned off if desired
to return the original drink dispenser with which the system is
integrated to a normal mechanical operation.
Another object of the present invention is to provide a new and
improved automatic liquid dispenser employing novel means for
automatically filling cups of different sizes.
The foregoing and other objects of the present invention are
accomplished in an illustrated embodiment by way of representation
and not limitation comprising in combination with a liquid
dispenser of the type having a solenoid controlled dispensing valve
for discharging liquid into a cup or receptacle placed in a
receiving position. The automatic system comprises means activated
by the placement of a cup in a receiving position for initiating
the dispensing of liquid through solenoid controlled valves and
includes liquid contact means for making electrical contact through
the liquid dispensed into the cup for controlling the solenoid
valve to shut off the flow of liquid when the liquid reaches a
predetermined level.
For a better understanding of the present invention reference
should be had to the following detailed description taken in
conjunction with the drawings in which:
FIG. 1 is a side elevational view, with portions broken away of a
soft drink dispenser having an automatic control system in
accordance with the features of the present invention;
FIG. 2 is a front elevational view of the apparatus of FIG. 1;
FIG. 3 is a schematic, electromechanical diagram of the automatic
liquid dispenser system in accordance with the features of the
present invention;
FIG. 4 is an enlarged fragmentary elevational view illustrating
electrical contact members or probes in accordance with the
invention for providing automatic shutoff when predetermined liquid
filling levels are reached;
FIG. 5 is a front elevational view looking in the direction of
arrows 5--5 of FIG. 4; and
FIG. 6 is a cross-sectional view taken substantially along lines
6--6 of FIG. 4.
Referring now more particularly to the drawings, therein is
illustrated a new and improved automatic liquid dispenser
constructed in accordance with the features of the present
invention and generally referred to by the reference numeral 10.
The dispenser 10 includes a base or cup supporting platform 12
having a liquid drain therein, an upright support post 14 from
which is mounted a dispensing head 16 having a lower section 18 and
a modified upper or top section 20 constructed in accordance with
the features of the present invention. The lower support platform
12 is adapted to support cups 22 and 24 of several different sizes
placed in receiving position thereon beneath a liquid mixing
discharge funnel 26 having an outlet at the lower end thereof for
dispensing a flow of liquid into an awaiting cup.
The lower section 18 of the dispensing head 16 provides support and
enclosure for one or more solenoid controlled dispensing valves 28,
each having a solenoid winding 28a (FIG. 3) operable to open the
valves when energized with current, for example supplied from a
24-volt AC source. In a dispenser for soft drinks and the like one
of the solenoid valves may be supplied with syrup through a supply
tube 30 which extends rearwardly from the control valve and
downwardly through the support post 14 to a source of syrup (not
shown). A similar supply line is provided for carbonated water and
the syrup and carbonated water are mixed in the dispensing funnel
26 when the respective solenoid controlled valves 28 are open
during a dispensing operation. As shown in FIG. 1, the solenoid
valves 28 for syrup and carbonated water are arranged in tandem and
the syrup and carbonated water discharged through the valves is
directed via open ended tubes or conduits 32 as shown schematically
in FIG. 3 for mixing in the funnel 26 as the soft drinks are
dispensed. In dispensers for beverages other than soft drinks only,
one dispensing valve may be required and in other instances, more
than a pair of valves may be needed for dispensing the desired
number of different fluids.
In prior art devices, the control of fluid dispensing through the
solenoid valve 28 is provided by a mechanical actuator lever 34
extending downwardly from the dispensing head 16 toward the support
platform 12. The lower end of the lever or an adjustable extension
thereon is manually contacted by the placement of a cup 22 or 24 in
receiving position. As best shown in FIG. 1, the mechanical lever
24 is pivotable about a rib 36 provided in the lower section 18 of
the dispensing head and a bias spring 38 is provided to normally
bias the lever in a clockwise direction, as viewed in FIGS. 1 and
4, to a nondispensing or normally shut off position wherein the
solenoid windings 28a are de-energized and the respective valves
controlled thereby are closed. In the prior art devices, the lever
34 is normally provided with an adjustable lower extension for
making direct mechanical contact with the cups. In accordance with
the present invention, the adjustable lower lever extension is
removed as mechanical holding of a cup against the lever 34 or
direct contact between the cup and lever extension is no longer
required when the automatic dispensing system is in operation.
The upper end of the lever 34 is adapted to actuate the operator of
a microswitch 40 having a common terminal "C", a normally open
contact "n.o.," and a normally closed contact "n.c." The windings
28a of the one or more solenoid valves in the dispenser head 16 are
each wired in series with the normally open and common contacts of
the microswitch 40 (see FIG. 3). In the mechanical mode of
operation, when the lever 24 or lever extension is pivoted in a
counterclockwise direction as shown by the arrow "A" (FIG. 3) by
contact or engagement with a cup the normally open circuit is
closed via the microswitch and the solenoid windings 28a are
energized to pen the valves and thereby dispense fluid. In the
mechanical mode of operation of the prior art, the fluid flow once
initiated as described continues until the microswitch is
deactivated, usually when an operator manually removes a filled
cup. This situation oftentimes resulted in the overflow of cups as
operators frequently became busy with other chores or were
unattentive. Overflowing liquid causes sanitation problems and
economic waste and is carried away to the sewer through the drain
in the cup support platform 12.
In accordance with the present invention, the mechanical lever 34
of an existing or prior art drink dispenser (after having the lower
lever extension removed therefrom) is utilized for initiating a
dispensing cycle when either a large or small cup 22 or 24 is
placed in receiving position on the platform 12 by movement of the
cup in a lateral direction as indicated by the arrow "B" of FIGS. 1
and 4. A pair of depending contact members or probes 42 are
pivotally supported on a common bracket 44, which bracket is
removably attached to the mechanical lever 34 at the desired level.
As best shown in FIG. 6, the bracket 44 includes a slot 44a for
receiving the lever 34 and a removable thumb screw 46 is provided
for securing the bracket in place on the lever 34. The depending
probes or contact members 42 are preferably formed of stainless
steel for sanitary reasons and are adapted to make electrical
contact with liquid dispensed into an awaiting cup 22 or 24 placed
in a receiving position on the support platform 12 as shown in FIG.
4. The lower end portion of each probe is formed in a modified
"S-shaped" configuration as shown and at the lower end 42a or tip
the probes make contact with the liquid in a small cup 22 when the
liquid level reaches or approaches the upper rim of the cup at a
predetermined fill level indicated by the level line "C." In the
case of carbonated beverages the bubbles developed on the surface
of the liquid filling a cup 22 may make electrical contact with the
lower ends 42a of the probes 42 slightly before the liquid level
actually reaches the level "C," however, in the case of
noncarbonated beverages having relatively few bubbles develop on
the surface the liquid normally reaches the level "C" to establish
electrical contact through the liquid between the parallel
probes.
The difference in fill levels between various types of liquids most
commonly dispensed with the device 10 is relatively small and in
the most part inconsequential. Upwardly from the lower ends 42a,
the probes are provided with relatively straight, short length legs
42b and these legs comprise the base of the generally S-shaped
configuration of the probes as best shown in FIGS. 4. The probes 42
provide a mechanical as well as an electrical function and provide
a mechanical extension for the actuating lever 34 when installed
thereon. When cups 22 or 24 are placed in liquid receiving position
on the receiving platform 12 as shown by movement of the cups from
left to right in the direction of the arrows "B" the probes are
engaged momentarily and the lever 34 moves in a counterclockwise
direction. This action causes the common and normally open contacts
of the microswitch 40 to close. With a small size cup 22, the upper
edge of the rim is momentarily engaged against the legs 42b to
pivot the lever 34 and momentarily actuates the microswitch 40.
When the cup is released in placed as shown, the lower ends 42a of
the probes are extended into the interior of the cup ready for
making electrical contact with the liquid dispensed therein when
the liquid reaches the predetermined filling level "C." Vertical
adjustment of the probe support bracket 44 on the lever 34 by
loosening and retightening the thumb screw 46 provides an easy and
rapid means for adjusting the height of the filling level "C" above
the platform 12. Once the upper lip of a cup 22 is passed under the
lower ends 42a of the probes and released to rest in the receiving
position as shown, there is no forceful engagement between the
probes and the cup and the lever 34 and probes 42 then return to
the normal or neutral position under the influence of the bias
spring 38. In the neutral position the microswitch 40 is no longer
actuated by the upper end of the lever 34. The "S-shaped" portion
of the probes 42 provides a secondary, higher level, electrical
contact area indicated by the reference numeral 42c for controlling
the dispensing of the liquid when filling cups 24 of larger height.
This second or higher predetermined filling level is indicated by
the level line "D." As larger cups 24 are moved into receiving
position on the platform 12 in the direction of the arrows "B" of
FIG. 4, the upper edge or lip of the cup is passed under the
contact areas 42c and the outside surface of the cup is contacted
against the legs 42b momentarily thereby pivoting the lever 34 to
momentarily actuate the microswitch 40 as previously described.
After the momentary contact between a cup 24 and the probe legs 42b
is discontinued by release of the cup to rest in the receiving
position as shown, the cup surface may be spaced slightly apart
from the legs 42b of the probes (distance "E") so that the bias
spring 38 again returns the lever 34 and probes 42 to the normal or
neutral position wherein the microswitch 40 is no longer actuated.
It should be noted that both the small and large cups 22 and 24 are
tilted slightly as they are moved into receiving position on the
platform 12 and the arrow "B" indicates the relative path of travel
of the cups during this movement. The cups are tilted slightly
during movement into the receiving position but when released for
filling, the cups rest in the upright position normally spaced
apart from the probes mechanically as shown in enlarged detail in
FIG. 4. The lower contact areas at the ends 42a of the probes
extend into the interior of the small cups 22 ready for terminating
the flow at the end of the dispensing cycle when the liquid in the
cup reaches or approaches the level "C." Similarly, with the large
cups 24, the outer edge of the cup is spaced slightly from the
mechanical engagement with the forward edges of the legs 42b of the
probes so that the probes 42 and lever 34 may remain in the neutral
position during the filling operation in a large cup without
maintaining the actuation of the microswitch 40 as the filling
operation proceeds.
At the upper end portion, each probe 42 includes a straight section
extended upwardly through a passage provided in a support block 48.
The support blocks are removably secured for pivotal movement on
opposite sides of the probe support bracket 44. As best shown in
FIG. 6 a pair of removable thumb screws 50 are provided for
securing the probe support blocks 48 to the sides of the bracket
44. In addition to the provision for adjusting the level of the
probe support bracket 44 on the mechanical lever 34 by loosening
and retightening of the thumb screw 46, each individual probe 42
may be adjusted relative to its support block 48 and for this
purpose a transverse set screw 52 is provided. The upper end
portions of the probes 42 extend upwardly beyond the upper edges of
the support blocks 48 and male or female electrical connectors 54
are mounted on the upper ends of the probes for making electrical
contact with appropriate male or female connectors 56 that are
provided on flexible control leads 58.
As shown schematically in FIG. 3, and in FIGS. 1 and 4, the leads
58 from the probes 42 extend upwardly into the dispenser control
head 16 and pairs of male/female connectors 54 and 56 provide
convenient means for connecting and disconnecting the level sensing
probes from an electrical circuit board in the control head when it
is desired to remove the probes and supporting assembly for
cleaning or service purposes. As will be seen in FIG. 4, the upper
portions of the probes and the mechanical lever 34 are sloped from
the vertical in the normal or neutral position and placement of a
large or small cup in receiving position by insertion generally
transversely of the probes in the direction of the arrows "B" onto
the support platform 12 causes the probes and lever to pivot in a
counterclockwise direction indicated by the arrows "A."
The probes are pivotally interconnected with the support bracket 44
by means of the thumb screws 50 but pivotal movement of the probes
in a counterclockwise direction relative to the support bracket 44
is prevented by a pair of inwardly directed stop pins 60 which
engage surfaces defined by the sides of triangular shaped recess
44b on the rearward edges of side flanges of the bracket. Relative
pivotal movement of the probes 42 in a clockwise direction relative
to the support bracket is permitted, however as the pins may move
out of the recesses and this relative pivotal action permits liquid
filled cups 22 and 24 to be removed from the support platform 12
without substantial interference.
Referring now to FIG. 3 and the electrical portion of the schematic
diagram therein shown, it will be seen that 24-volt A.C. power is
supplied to the one or more solenoid windings 28a (which are
connected in parallel) through a pair of A.C. power leads 62 and
64. One lead 62 is connected to one end of the solenoid windings
and the other lead 64 is connected to the normally open (n.o)
contact of the microswitch 40. The common (c) contact of the
microswitch is connected via a lead 66 to the opposite end of the
one or more solenoid windings 28a so that any time the manual
actuator lever 34 depresses the microswitch the solenoids are
energized with 24-volt A.C. power to open the valves 28 controlled
thereby and permit fluid flow.
In accordance with the present invention, the lower section 18 of
the dispenser control head 16 supports the solenoid valves 28, the
microswitch 40 and the mechanical actuator lever 34 along with the
probe assembly associated therewith. However, the existing or
original equipment upper section of the dispensing head is replaced
by a new upper section 20 constructed in accordance with the
features of the present invention. The new upper head section 20 is
designed and adapted to replace the upper sections originally
furnished with an existing dispenser 10 and when replacement is
made along with electrical connections and installation of the
probe assembly, an existing dispenser is converted rapidly and
easily into an automatic unit in accordance with the present
invention. As best shown in FIG. 1, the upper section 20 of the
dispenser head comprises a housing having a front wall, a back wall
and an inverted U-shaped cross-sectioned top and side wall
combination secured in place on the lower housing section 18 by a
single cap screw 68 which is threadedly received in a bracket 28b
normally provided with the dispenser for holding solenoid windings
of the valves 28 in place. As indicated in FIG. 2, the front wall
of the upper housing section 20 provides a supporting panel for a
double pole, single throw, "on-off" switch indicated by the
reference numerals 70 in FIGS. 1, 2 and 3. To the left of the
switch as viewed in FIG. 2, there is provided a normally closed,
pushbutton type, "start" switch 72 and on the right hand side of
the switch 70 there is provided a normally open, pushbutton type,
"stop" switch 74. The automatic control feature in accordance with
the present invention can be locked in or out with the switch 70
and by moving the switch to the "off" position normal mechanical
operation of the dispenser with the lever 34 is utilized. In
addition, manual electrically controlled operation of the unit can
be obtained by starting and stopping of a dispensing cycle with the
pushbutton 72 and pushbutton switch 74, respectively.
Referring now to FIGS. 1 and 2, the automatic control system of the
present invention includes a circuit generally indicated by the
reference numeral 76 (FIG. 3) and preferably provided on printed
circuit board 78 mounted in the upper portion of the upper head
section 20. Low voltage D.C. power in the order of 41/2 volts may
be obtained for operation of the circuit 76 either through a step
down transformer 80 and the rectifiers 82 powered from the 24-volt
A.C. source used for the solenoid windings 28a and in this case
electrical connection to the 24-volt A.C. source within the head 16
may be conveniently made, or a separate source of low voltage D.C.
power may be used. When installing the automatic system of the
invention on an existing manually operated dispenser the electrical
connections are simple to make and are conveniently
accomplished.
Positive D.C. voltage is supplied to the circuit 76 through one
side (right hand) of the on-off switch 70 and a lead 84 is
connected from the switch to one terminal of the normally closed,
push button start switch 72. The opposite terminal of the "start"
switch 72 is connected via a lead 86 to the normally closed (n.c.)
contact of the microswitch 40 in the lower housing section 18 of
the dispensing head 16. With the microswitch in the unactuated or
normal position, a current path is provided through the normally
closed (n.c.) terminal and the common (c) terminal and positive
voltage is thus supplied via a lead 88 and branch lead 90 to one
side of a relay coil 92. The coil when energized operated to open a
pair of normally closed contacts which are wired in parallel with
the common (c) and normally open (n.o.) terminals of the
microswitch 40 via the lead 88 and a lead 94. The other side of the
"on-off" switch 70 is wired in the lead 88 between the common
terminal (c) of the microswitch 40 and the right hand contact of
the normally closed, relay contacts operationally controlled by the
relay coil 92. When the "on-off" switch 70 is moved to the off
position, the normally closed contacts of the relay coil 92 can no
longer make the circuit to energize the solenoids 28a and only
manual operation of the dispenser can be utilized.
The relay coil 92 is parallel with a resistor 96 and is normally
energized by a silicon controlled rectifier 98 in order to maintain
the contacts of the relay coil 92 open. This allows the solenoid
valves 28 to be operated by mechanical actuation of the microswitch
40. The energizing circuit for the relay coil 92 includes the lead
94, the normally closed switch 72, the normally closed contacts of
the microswitch 40, the lead 90, the relay coil 92, the anode of
the silicon controlled rectifier 98, which is connected to the
relay coil 92, and the cathode of the silicon controlled rectifier
98 which is connected to the negative source of direct current
potential. When current through the energizing circuit for the
relay coil 92 is interrupted by opening either the normally closed
"start" switch 72 or the normally closed contacts of the
microswitch 40, the silicon controlled rectifier 98 is rendered
nonconductive and remains nonconductive until a triggering signal
is applied to its gate. When the silicon controlled rectifier 98 is
rendered nonconductive, the contacts of the relay coil 92 close to
energize the solenoid valves 28 and dispense the beverage.
The triggering of the silicon controlled rectifier 98 is controlled
by a transistor 104 having its emitter connected to the gate of the
controlled rectifier 98, its collector connected to a source of
direct current potential by resistors 106 and 114 and the normally
closed contacts of the microswitch 40. The emitter of the
transistor 104 is connected to a source of negative potential (lead
100) by means of a resistor 110. A capacitor 108 is connected
between the base of the transistor 104 and the source of negative
potential to filter out switching transients.
Once the silicon controlled rectifier 98 has been rendered
nonconductive to dispense the beverage, the dispensing of the
beverage is terminated by again rendering the controlled rectifier
98 conductive. This is accomplished by applying a positive
potential to the base of the transistor 104. The positive potential
is obtained from the common terminal (c) of the microswitch 40 and
may be applied to the base of the transistor 104 by either the
"stop" switch 74 or an electrical connection between the probes
42.
In automatic operation, the electrical connection between the
probes is provided by the conductivity of the beverage when the
liquid reaches the predetermined upper or lower contact areas 42a
or 42c of the probes. The stop switch 74 serves to terminate the
dispensing of the beverage should the level of the beverage fail to
reach the probes for any reason. Alternatively, the "start" switch
push button 72 and the stop switch push button 74, which are
momentary type switches, may be used to manually control the
dispensing operation. In automatic operation, the dispensing
operation is initiated by actuating the mechanical lever 34 and
terminated by the liquid reaching one of the predetermined levels
on the probes dependent on whether a small cup 22 or large cup 24
is placed in receiving position.
Although the present invention has been described with reference to
a single illustrative embodiment thereof, it should be understood
that numerous other modifications and embodiments can be devised by
those skilled in the art that will fall within the spirit and scope
of the principles of this invention.
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