U.S. patent number RE34,337 [Application Number 07/308,863] was granted by the patent office on 1993-08-10 for beverage dispenser with automatic cup-filling control and method for beverage dispensing.
This patent grant is currently assigned to IMI Cornelius Inc.. Invention is credited to Clay Bennett.
United States Patent |
RE34,337 |
Bennett |
August 10, 1993 |
Beverage dispenser with automatic cup-filling control and method
for beverage dispensing
Abstract
An automatic cup-filling control arrangement for beverage
dispensers utilizes the spray or mist of liquid droplets, formed by
flowing beverage striking beverage already in the cup, to complete
an electrical circuit. This electrical circuit extends from an
electrically conducting member, such as an actuating lever, to
beverage flowing through a dispensing valve. When the mist of
droplets permits a pre-established magnitude of current to flow
between the actuating lever and the flowing beverage, which occurs
when beverage in the cup reaches a pre-determined level, dispensing
of the beverage is terminated.
Inventors: |
Bennett; Clay (Payson, AZ) |
Assignee: |
IMI Cornelius Inc. (Anoka,
MN)
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Family
ID: |
26976487 |
Appl.
No.: |
07/308,863 |
Filed: |
February 9, 1989 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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Reissue of: |
743568 |
Jun 11, 1985 |
04641692 |
Feb 10, 1987 |
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Current U.S.
Class: |
141/95; 327/110;
141/198; 141/1; 307/118 |
Current CPC
Class: |
A47J
31/402 (20130101); G07F 13/10 (20130101); B67D
1/1238 (20130101) |
Current International
Class: |
A47J
31/40 (20060101); B67D 1/12 (20060101); B67D
1/00 (20060101); G07F 13/10 (20060101); B65B
003/04 () |
Field of
Search: |
;141/1,95,94,96,83,192,198,360,361,362 ;73/29R,34R,294 ;137/390,392
;307/118,247.1 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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1206609 |
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Dec 1965 |
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DE |
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2234105 |
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Feb 1973 |
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DE |
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1388755 |
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Jul 1965 |
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FR |
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295506 |
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Mar 1954 |
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CH |
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153916 |
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Aug 1963 |
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SU |
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819448 |
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Sep 1959 |
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GB |
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Primary Examiner: Cusick; Ernest G.
Attorney, Agent or Firm: Hakanson; Sten Erik
Claims
I claim:
1. A beverage dispenser having an arrangement for automatically
controlling the filling of a cup.Iadd., the cup having a top rim
and having an interior volume for holding the beverage, the
boundaries of the interior volume defined generally by a cup bottom
surface, a cup sidewall surface and a top surface, the top surface
having a perimeter defined by the cup rim, the beverage dispenser
.Iaddend.comprising:
at least one valve means for controlling discharge of beverage from
said .Iadd.at least one .Iaddend.source into the cup to be
filled;
actuating means to cause said .Iadd.at least one .Iaddend.valve
means to be energized to initiate dispensing of the beverage into
the cup to be filled;
an electrically conductive member associated with the beverage
dispenser and disposed to be positioned adjacent to and outside of
the cup that is being filled;
circuit means electrically interconnecting said electrically
conductive member and said .Iadd.at least one .Iaddend.valve means
to thereby electrically interconnect said conductive member with
beverage flowing through said .Iadd.at least one .Iaddend.valve
means .Iadd.and the conductive member providing for such current
flow wherein no portion thereof extends into the volume of the cup
and wherein no portion thereof extends transversely therefrom
terminating adjacent to the cup top surface.Iaddend.; and
control means for operating said .Iadd.at least one .Iaddend.valve
means in response to a change in impedance between said
electrically conductive member and the beverage, when the cup has
been filled to a predetermined level, to discontinue beverage flow
to the cup.
2. A beverage dispenser as claimed in claim 1 wherein said
actuating means and said electrically conductive member are
combined in an actuating lever.
3. A beverage dispenser as claimed in claim 2 wherein said
actuating lever is activated by pressing the cup to be filled
against it.
4. A beverage dispenser as claimed in claim 1 wherein the change in
impedance is effected by droplets of beverage, which are produced
by flowing beverage striking beverage already in the cup, forming
an electrical current path between said electrically conductive
member and the beverage.
5. A beverage dispenser as claimed in claim 4 wherein said droplets
of beverage are in a foam created during the dispensing of a
carbonated beverage.
6. A beverage dispenser as claimed in claim 4 wherein said control
means comprises a flip-flop circuit that changes state upon current
flow of a pre-established magnitude between the beverage and said
electrically conductive member, the change in state of said
flip-flop circuit closing said .Iadd.at least one .Iaddend.valve
means to terminate beverage flow to the cup being filled.
7. A beverage dispenser as claimed in claim 1 wherein said
.[.circuit means comprises a continuous metallic path from.].
.Iadd.at least one valve means further includes .Iaddend.an outer
metallic structure .[.of said valve means.]. .Iadd.and said circuit
means further including a continuous metallic path from said outer
metallic structure .Iaddend.to beverage passing through said
.Iadd.at least one .Iaddend.valve means to .[.complete an.].
.Iadd.provide for .Iaddend.electrical connection to the
beverage.
8. A beverage dispenser as claimed in claim 7 wherein said circuit
means further .[.comprises.]. .Iadd.includes .Iaddend.an electrical
connection from said metallic structure to .Iadd.a .Iaddend.logic
ground.
9. A beverage dispenser as claimed in claim 1 wherein said .Iadd.at
least one .Iaddend.is a solenoid valve and said control means
comprises:
a power switch to pass electrical energy to said solenoid valve
when beverage is to be dispensed; and
a flip-flop circuit to close said power switch when said solenoid
valve is to be energized, said flip-flop circuit changing state to
open said power switch in response to said change in impedance
between said electrically conductive member and the beverage.
10. A beverage dispenser as claimed in claim 1 wherein a portion of
said control means is also a part of said circuit means.
11. A beverage dispenser as claimed in claim 1 .[.wherein a
plurality of beverage sources and associated valves are.].
.Iadd.and further including a plurality of valve means each valve
means connectable to a separate source of beverage and said
plurality of valve means .Iaddend.controlled by said control
means.
12. A beverage dispenser as claimed in claim 1 and further
comprising a manual override switch to re-initiate dispensing if
the cup was not filled to the pre-determined level during the
previous dispensing operation.
13. A beverage dispenser having an arrangement for automatically
controlling the filling of a cup, .Iadd.the cup having a top rim
and having an interior volume for holding the beverage, the
boundaries of the interior volume defined generally by a cup bottom
surface, a cup sidewall surface and a top surface, the top surface
having a perimeter defined by the cup rim, the beverage dispenser
.Iaddend.comprising:
at least one source of beverage;
at least one solenoid valve for controlling discharge of beverage
from said .Iadd.at least one .Iaddend.source into the cup to be
filled;
an outer metallic structure associated with said .Iadd.at least one
.Iaddend.solenoid valve, a continuous metallic path existing from
said metallic structure to beverage passing through said solenoid
valve;
a power supply;
an electrical connection from said metallic structure .[.one side
of.]. said power supply;
a power switch to pass power to said at least one solenoid valve
when beverage is to be dispensed;
an actuating lever to initiate dispensing of beverage;
a flip-flop circuit responsive to said actuating lever to close
said power switch when said at least one solenoid valve is to be
energized to dispense beverage; and
an electrical circuit including said flip-flop circuit, said power
supply, said electrical connection, said metallic structure and
said metallic path to electrically interconnect said actuating
lever and the beverage flowing through said .Iadd.at least one
.Iaddend.valve during dispensing, said circuit being completed for
current flow of a pre-established magnitude by droplets of
beverage, which are produced by flowing beverage striking beverage
in the cup when the cup has been filled to a .[.pre-determined.].
level .Iadd.permitting such pre-established current flow.Iaddend.,
the current of said pre-established magnitude changing the state of
said flip-flop circuit to open said power switch and de-energize
said .Iadd.at least one .Iaddend.solenoid valve.Iadd., and the
actuating lever providing for such current flow wherein no portion
thereof extends into the volume of the cup and wherein no portion
thereof extends transversely therefrom terminating adjacent to the
cup top surface.Iaddend..
14. A beverage dispenser as claimed in claim 13 wherein said
electrical connection .[.comprises.]. .Iadd.is connected to a logic
ground side of said power supply and wherein said electrical
connection further includes .Iaddend.a resistor and a capacitor
.Iadd.connected .Iaddend.in parallel between said metallic
structure and said logic ground. .Iadd.
15. A method for automatically filling a cup, the cup having a top
rim and having an interior volume for holding the beverage, the
boundaries of the interior volume defined generally by a cup bottom
surface, a cup sidewall and a top surface, the top surface having a
perimeter defined by the cup rim, the method comprising the steps
of:
placing the cup adjacent an electrically conductive member,
dispensing beverage into the cup from a valve,
electrifying the beverage as it is dispensed into the cup,
sensing a current flow between the beverage and the conductive
member during the dispensing of beverage into the cup, and the
sensed current flow occurring wherein no portion of the conductive
member extends into the volume of the cup and wherein no portion
thereof extends transversely therefrom terminating adjacent to the
cup top surface, and
stopping the flow of beverage from the valve to the cup when the
sensed current flow exceeds a pre-determined value. .Iaddend.
.Iadd.
16. The method as defined in claim 15, and further including the
steps of re-initiating the dispensing of the beverage into the cup
after a first stopping of the flow of beverage from the valve to
the cup,
sensing a current flow between the beverage and the conductive
member during the re-initiated dispensing of beverage into the cup,
and the sensed current flow occurring wherein no portion of the
conductive member extends into the volume of the cup and wherein no
portion thereof extends transversely therefrom terminating adjacent
to the cup top surface, and
stopping the flow of beverage from the valve to the cup when the
sensed current flow again exceeds the pre-determined value.
.Iaddend. .Iadd.
17. The dispenser as defined in claim 1, and said actuating means
and electrically conductive member comprising an electrically
conductive lever, and the lever pivotally secured and depending
below the at least one valve means and having a substantially flat
electrically conductive cup facing surface portion for contacting
the cup when the cup is pressed against the lever. .Iaddend.
.Iadd.18. The dispenser as defined in claim 13, and the lever
pivotally suspended and depending below the at least one valve
means and having a substantially flat electrically conductive cup
facing surface for contacting the cup when the cup is pressed
against the lever. .Iaddend. .Iadd.19. A beverage dispensing
apparatus for filling a cup with a liquid beverage, the cup having
a top rim and having an interior volume for holding the beverage,
the boundaries of the interior volume defined generally by a cup
bottom surface, a cup sidewall surface and a top surface, the top
surface having a perimeter defined by the cup rim, the dispensing
apparatus automatically filling the cup to a level substantially
adjacent to the cup top surface, the beverage dispensing apparatus
comprising:
a beverage dispensing valve connected to a source of beverage, and
including a solenoid for opening and closing the valve,
switch means connected to an electrical power source and to the
solenoid to pass power thereto for operating the solenoid,
a lever pivotally secured and depending below the valve, the lever
for actuating the switch means by pressing of the cup to be filled
against the lever, and the lever having a substantially flat
electrically conductive surface portion along a length thereof for
contacting the cup when the cup is pressed there against, and
electrical circuit means connected to the electrical power source
for providing electrical current to the valve for electrically
connecting the current source to the beverage as it flows from the
source thereof through the valve and is dispensed into the cup, and
the circuit including electrical control means, the control means
connected to the conductive portion of the lever and to the
solenoid for closing the valve and stopping dispensing of beverage
into the cup when the control means senses a pre-established
magnitude of current flow between the beverage and the lever
conductive portion, and the conductive portion providing for such
current flow wherein no conductive portion thereof extends into the
volume of the cup and wherein no conductive portion thereof extends
transversely from the lever terminating adjacent to the cup top
surface. .Iaddend. .Iadd.20. A beverage dispenser as claimed in
claim 19, and the control means further including means to
re-initiate dispensing if the cup interior volume was not filled
with the beverage to a desired level during a previous dispensing
operation. .Iaddend.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates generally to beverage dispensers, and more
specifically, this invention relates to a .Iadd.method of and a
.Iaddend.beverage controlling the filling of a cup to a
pre-determined level.
2. Description of the Prior Art
The dispensing of beverages into a cup for immediate consumption is
a long-established art. In the earlier forms of dispensers, the
beverage to be consumed was discharged into a cup or other
receptacle under manual control. Such an approach requires an
operator to institute dispensing and to terminate dispensing. This
system is acceptable in some environments, such as a soda fountain
or a concession stand, but even in such environments it requires
the operator to spend the time required to observe the filling of
the cup. Also, there is frequently considerable spillage, and the
portions of beverage will inevitably vary.
Most beverage dispensing involves the mixing of a flavor
concentrate with a suitable diluent, such as soda water or plain
water. There are two basic approaches to mixing the concentrate and
diluent. The first is the pre-mix approach (i.e., the concentrate
and diluent are mixed prior to dispensing), while this other is the
post-mix approach (i.e., the concentrate and diluent are mixed
during dispensing). With the advent of automatic vending machines,
the need for an automatic portion control was immediately obvious.
Some early beverage dispensers carried over the manual control
aspect, but the problems of spillage (including deliberate wasting)
and greatly variable size of portions required as automatic portion
control.
The automatic portion controls that were developed, and which are
still in use today, employ a measuring of the amount of pre-mixed
beverage (in the pre-mix application) or the amount of concentrate
and diluent (in the post-mix application) that are discharged.
While this system has been generally satisfactory, there are still
some problems that make automatic filling control based upon the
actual product in the cup, rather than the amount of beverage to be
discharged, highly desirable. Attempts to provide portion control
based upon beverage in the cup, such as a weight measuring system,
have not been very satisfactory.
While there may be some cases in which the portion control of
current dispensers is based upon the actual volume of beverage to
be discharged, most beverage dispensers now utilize solenoid
valves. Accordingly, the measurement of beverage to be discharged
is generally based upon actuating the solenoid valve for a given
amount of time. The time is calculated to permit the valve to
discharge the desired amount of beverage. However, the time
calculation is based upon a given rate of flow, which assumes a
given orifice size. During usage, the beverage (particularly the
concentrate in a post-mix system) may well accumulate to decrease
the effective orifice size, thus reducing the rate of flow and
resulting in a discharge of less beverage than desired. In the case
of a post-mix apparatus, not only may the portion be undesirably
small, but since accumulation will normally be more of a problem
with the concentrate than the diluent, the resulting beverage may
also be weaker than desired.
Another difficulty is that basing portion size upon amount of
beverage discharge, even if the portion control is not adversely
affected by accumulation of beverage build-up in the valve, is that
the dispensed portion is dependent upon the size of the cup. In
other words, only a single size of cup may be utilized. However, in
many locations, such as, for example, a cafeteria line, it is
desirable to be able to dispense beverages in a variety of sizes of
cups. Since it is usually not feasible to have a separate dispenser
for each size of cup, manually controlled dispensers are still
generally employed in such locations. The result, as indicated
above, is spillage or waste and variation in the size of the
portions. Automatic control based upon the level of liquid in a
cup, regardless of the size of the cup, would be most helpful in
environments such as this.
SUMMARY OF THE INVENTION
The present invention provides an arrangement for accurately
filling a cup with beverage to a pre-determined level, regardless
of the size of the cup and based upon the amount of beverage in the
cup, rather than the amount of beverage discharged by the
dispenser. This highly desirable result is achieved by establishing
an electrical circuit through the flowing beverage and a mist or
foam of droplets of the beverage that are produced by flowing
beverage striking the beverage in the cup. Since the invention
works the same for both a pre-mixed or post-mixed beverage, the
term beverage, as used herein, will refer not only to a completed
mixture of the constituents, but also to the individual
constituents singly or in combination.
The present invention will be utilized in connection with a
dispenser having one or more sources of beverage, such as
relatively large containers, from which a beverage or a selection
of beverages may be discharged. Beverage from the containers is
conveyed to a valve assembly for discharge controlled by a valve,
preferably a solenoid valve. In the case of pre-mixed beverages,
there will be a single container and a single solenoid valve for
each beverage to be dispensed, while in the case of post-mixed
beverages there will be a container of concentrate and a container
of diluent, each with its associated solenoid valve, for each
beverage to be dispensed. As the operation of the invention is
substantially identical for both a pre-mixed beverage apparatus and
a post-mixed beverage apparatus, with the exception of the number
of solenoids to be energized and the number of valves, the
description herein is applicable to both types of systems.
In order to complete an electrical circuit to the beverage flowing
through the solenoid valves, advantage is taken of the fact that a
continuous metallic path exists between beverage passing through
each of the solenoid valves and an outer metallic structure, such
as a mounting member or a magnetic shield surrounding the solenoid
valves. As a result of this continuous metallic path, electrical
current can pass from the outer metallic structure to the flowing
beverage. By connecting the outer metallic structure into an
electrical circuit, such as by connecting it to one side of a power
supply, the flowing beverage may be included as part of the
complete electrical circuit.
Energization of the solenoid valves is dependent upon a power
switch that is closed to pass power to the solenoid when beverage
is to be dispensed. An example of a suitable power switch is a
triac connected in series with the solenoid coils.
Control of the triac power switch is achieved through a flip-flop
circuit that produces a signal to trigger the triac to a conducting
or closed circuit condition when it is desired to energize the
solenoid valves to dispense a beverage. Activation of the flip-flop
circuit to produce this signal is achieved by means of an actuating
lever that energizes a microswitch to trigger the flip-flop
circuit. This actuating lever is normally activated by pressing the
cup to be filled against the actuating lever, which then initiates
dispensing of the beverage. Alternatively, the cup could be placed
adjacent a stationary electrically conductive member and initiation
of dispensing could be achieved by a different actuating mechanism,
such as a push button.
An electrical circuit, which includes the flip-flop circuit, a
power supply, the connection from the power supply to the outer
metallic structure of the solenoids, and the metallic path from the
outer metallic structure to the interior of the valves,
interconnects the actuating lever (or other electrically conductive
member) and the flowing beverage. As the cup fills with the
beverage, a mist or spray of small droplets of the beverage (in the
case of a carbonated beverage the droplets are in the form of a
foam) increases the amount of moisture between the actuating lever
and the stream of beverage. This mist or spray results from the
flowing beverage striking the beverage in the cup and causing the
droplets to be thrown into the air. In the case of a post-mixed
beverage, this spray or mist may include droplets of the
constituents as well as the mixed beverage.
As the beverage in the cup reaches a pre-determined level, the
density of the mist between the actuating lever and the flowing
beverage increases to the point that the impedance between the
lever and the beverage is decreased to a value that permits a
current flow of a pre-established magnitude to flow. This
pre-established magnitude of current will trigger the flip-flop to
change states and cause the triac to return to a non-conducting or
open circuit condition, thus de-energizing the solenoid valves and
terminating the dispensing of the beverage.
If for some reason the cup has not been filled to the desired
level, a manual override switch is provided to set the flip-flop
circuit to trigger the triac to the closed circuit condition and
start the cup-filling sequence over again.
With this arrangement, the pre-determined level to which the cup is
to be filled can be selected by adjusting the magnitude of current
required to established a triggering of the flip-flop. Thus, the
cup will be filled to the pre-determined level regardless of the
size of the cup and without depending upon the discharge of a
premeasured quantity of beverage.
.Iadd.A method of dispensing beverage into a cup with level sensing
and respective automatic shut-off of dispensing includes permitting
an electrical current to flow to an electrically conductive member
outside of and adjacent to the cup. .Iaddend.
These and other objects, advantages and features of this invention
will hereinafter appear, and for purposes of illustration, but not
of limitation, an exemplary embodiment of the subject invention is
shown in the appended drawing.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a side elevational view of a beverage dispenser valve
assembly and dispensing nozzle constructed in accordance with the
present invention.
FIG. 2 is a front elevational view of the beverage dispensing valve
assembly and dispensing nozzle of FIG. 1.
FIG. 3 is a top plan view of the beverage dispenser portion of FIG.
1.
FIG. 4 is a schematic circuit diagram of an automatic fill-control
circuit constructed in accordance with the present invention.
FIG. 5 is a cross-sectional view taken line 5--5 of FIG. 1.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
A preferred embodiment of a solenoid valve arrangement, with a
dispensing nozzle, for achieving the goals of the present invention
is illustrated in FIGS. 1-3 and 5. Although this invention may be
utilized equally well with either a pre-mix or a post-mix type of
dispenser, the preferred embodiment disclosed herein illustrates
the use of the invention in a post-mix apparatus. As indicated
above, the term "beverage" will be used in a general sense to refer
both to the completed beverage to be consumed and to the individual
constituents, such as concentrate and/or diluent.
A solenoid valve structure 11, in this preferred embodiment,
includes a pair of solenoid coils 13 and 15. Of course, if a
pre-mixed beverage were to be discharged, only a single solenoid
coil and the corresponding valve would be utilized. Solenoid coils
13 and 15 are any suitable type of electrically energized coil,
various types of which have been utilized in the dispensing field
in the past.
Each of the solenoids 13 and 15 is secured to an associated
mounting bracket 17 or 19, respectively. Mounting brackets 17 and
19 are formed of any suitable relatively strong metal to adequately
support the respective solenoid coils 13 and 15 and to provide a
magnetic path about the solenoid structure. Mounting brackets 17
and 19 are secured to their respective solenoids by lock nuts 21
and 23. Brackets 17 and 19 are interconnected by a retaining strip
24 that is secured to the respective frames at each end thereof by
the lock nuts 21 and 23.
Electrical energy is supplied to solenoid 13 by means of angle tabs
25 and 27, while electrical energy is supplied to solenoid 15
through similar angle tabs 29 and 31. In this preferred embodiment,
the solenoids are AC solenoids energized from a 24 volt source of
alternating current, although any suitable electrical power source
could be employed with appropriate current modification.
Each of the solenoids 13 and 15 is also mounted on an associated
valve body 33 and 35, respectively. Valve body 35 is also provided
with an output nozzle 37 that is the dispensing nozzle of the
dispenser. Nozzle 37 is secured to valve body 35 by a washer or
other retaining member 36 and a pair of attaching devices, such as
screws 38 and 40.
A metallic valve housing 39 is secured in valve body 35 with a
suitable liquid-tight seal 41. Metallic housing 39 has a generally
cylindrical extending portion 43 that fits in the core of solenoid
coil 15 to provide a metallic sleeve in which the metallic plunger
45 of solenoid 15 reciprocates. Sleeve 43 is sealed at its upper
end by an extending metallic stem 47, to which lock nut 23 is
affixed.
Since stem 47 is in intimate contact with sleeve 43, there is a
continuous metallic path from stem 47 to housing 30. In addition,
metallic plunger 45 rides in sleeve 43 with a relatively close
tolerance and is electrically connected to sleeve 43 either by
direct contact therewith or by a liquid film therebetween. Thus, an
electrical connection to any beverage located in the interior 49 of
housing 30 may be made through stem 47.
Plunger 45 is provided with a valve plug 51, which is normally
driven into contact with a valve seat 53 by a bias spring 55.
Energization of solenoid 15 will move plunger 45 against the bias
of spring 55 to remove the valve plug 51 from valve seat 53. This
opens the interior 49 of housing 30 to the nozzle 37. Therefore, so
long as solenoid 15 is energized, beverage introduced to the
interior 49 of housing 39 through a conduit 57 may be passed to
nozzle 37 through a conduit 59 for discharge into a suitable cup
61. (The term "cup" is understood to refer to any suitable
receptacle for the beverage.)
A similar metallic housing 63 and sleeve 65 is mounted on valve
body 33 for the solenoid 13. In the case of a post-mix apparatus as
disclosed herein, the solenoid 15 might be used to control the
discharge of concentrate, while solenoid 13 might be utilized to
control the discharge of a diluent, such as soda water or plain
water.
Housings 39 and 63 are secured to valve bodies 33 and 35 by a
retaining clip 67. Retaining clip 67 is secured to valve bodies 33
and 35 by suitable attaching devices, such as screws 69, 71, 73,
75, 77 and 79.
Inlet bushings 81 and 83 provide a source of beverage. In this
preferred embodiment of a post-mix apparatus, a beverage
concentrate and a diluent are inserted through these bushings. Set
screws 85 and 87 may be utilized to secure inlet bushings 81 and 83
to valve body 33. A flow control assembly 89 is mounted on valve
body 33 and is provided with a set screw 91 for adjustment
thereof.
To initiate dispensing, an actuating lever 93 is provided.
Actuating lever 93 is illustrated as U-shaped bale in this
preferred embodiment, although any suitable shape of size of
actuating lever may be utilized. For purposes of this invention, a
significant aspect of actuating lever 93 is that it be constructed
of an electrically conducting metal. (It may be noted that it would
also be possible to place a stationary electrical conducting member
adjacent the cup and to initiate dispensing by a different type of
actuator, such as a push-button on the dispenser.)
A mounting bracket 95 for actuating lever 93 is mounted on valve
body 33 by suitable attaching devices such as screws 97 and 99.
Actuating lever 93 is also mounted on a cross arm 101 through a
sleeve 103 placed between retaining rings 105 and 107. A reduced
diameter portion 109 of actuating lever 93 extends above retaining
ring 107.
Actuating lever 93 is mounted for a pivoted motion as the bottom
end thereof adjacent nozzle 37 is pushed away from the nozzle 37.
This pivoting motion of actuating lever 93 causes sleeve 103 to
bear against a flexible spring-type arm 111. As arm 111 is flexed,
it bears against a microswitch 113 to initiate dispensing of
beverage by the apparatus. A flexible arm 115, similar to arm 111,
is located opposite the flexible arm 111.
A circuit for achieving the automatic fill control of the present
invention is illustrated in FIG. 4. An AC source is connected to
terminals 117 and 119, such as a 24 volt AC supply. In the circuit
of this preferred embodiment, terminal 119 is the AC or logic
ground. When microswitch 113 is in its normal or non-actuated
position, actuating lever 93 (shown schematically) is electrically
connected to ground through microswitch 113.
The 24 volt AC signal is half-wave rectified by diode D1. The
half-wave rectified output of diode D1 is passed to a voltage
regulator circuit 121 through a current limiting resistor R1.
Voltage regulator 121 provides a 15 volt DC potential to ground
(V+) at terminals 123 and 125. A filter capacitor C1 at the input
of voltage regulator 121 is connected in parallel with a bleed
resistor R2 at the input to voltage regulator 121. Another bleed
resistor R3 is connected to ground at the output of voltage
regulator 121.
A noise suppressor 127, such as a pair of back-to-back Zener
diodes, may be provided at the input across terminals 117 and 119.
However, in many applications, this noise suppressor will not be
required.
Solenoid coils 13 and 15 are shown schematically, as well as the
plunger or armature 45 for coil 15 and a similar armature or
plunger 129 for solenoid coil 13. A resistor R4 and a capacitor C2
connect a metallic component or structure 131 of the solenoid
structure to logic ground. The metallic structure 131 may be any
portion of the solenoid valve structure 11 that provides an
electrically conductive path to the beverage in an associated
housing, such as housing 39 associated with solenoid coil 15. Thus,
in the valve assembly described above, metallic structure 131 could
be stem 47. In other solenoid arrangements, a magnetic shield is
placed around the solenoids and is connected with a metallic path
to the beverage in the valve, and thus such a magnetic shield could
serve as the metal component 131. In any event, the necessary
aspect is that an electrical connection be made from one side of
the supply, in this case the AC ground, to a beverage passing
through the valve for dispensing.
Energization of solenoids 13 and 15 is controlled by a power
switch, in this preferred embodiment a triac 133 connected between
solenoid coils 13 and 15 and ground. A series arrangement of a
resistor R5 and a capacitor C3 is connected across the triac to
provide a filtering function and to assure turnoff of the triac at
the end of the dispensing function.
A control signal, in the form of a gating current, is applied to
the gate of triac 133 by a transistor Q1 through a resistor R6.
Transistor Q1 has a resistor R7 connected between its emitter and
base, and the input signal to the base is supplied through a
resistor R8.
The input signal to the base of transistor Q1 is provided b a
flip-flop circuit formed by NAND gates 135 and 137. The outputs of
the flip-flop circuit is inverted by NAND gates 139 and 141. NAND
gates 135, 137, 139 and 141 are located in a standard CMOS chip,
which provides a highly sensitive flip-flop circuit that responds
to relatively very small changes in current. Pins of the flip-flop
circuit chip are indicated by the corresponding numerals 1-14.
A parallel arrangement of a resistor R9 and a capacitor C4 connects
one of the inputs of NAND gate 135 to the other input of that NAND
gate and to the output of NAND gate 137. One side of this circuit,
and one input to NAND gate 135, is also connected directly to the
electrical circuit that leads to actuating lever 93.
A resistor R10 and capacitor C5 are connected from the DC potential
at terminal 125 to an input of NAND gate 137. The mid-point of
resistor R10 and capacitor C5 is connected to the normally open
terminal 143 of microswitch 113. Another resistor R11 is connected
in parallel across resistor R10 and capacitor C5.
Closing of microswitch 113 by activation of actuating lever 93
provides a set signal through capacitor C5 to the input of NAND
gate 137 to initiate dispensing. In the event that the dispensing
operation, described hereinafter, does not fill cup 61 to the
desired level, a manually actuated switch 145 may be supplied to
re-initiate the dispensing operation.
While the components of the circuit of FIG. 4 may be varied to
achieve desired results in any particular application, a circuit
utilizing the following components has been successfully
operated:
______________________________________ COMPONENT VALUE OR TYPE
______________________________________ R1 47 ohm. 1/4 watt R2 4.7
kohm. 1/4 watt R3 47 kohm. 1/4 watt R4 100 kohm. 1/4 watt R5 100
ohm. 1/4 watt R6 1 kohm. 1/4 watt R7 3 kohm. 1/4 watt R8 3 kohm.
1/4 watt R9 1 megohm. 1/4 watt R10 100 kohm. 1/4 watt R11 100 kohm.
1/4 watt C1 150 microfarad, 35 volt C2 .01 microfarad, 100 volt C3
.01 microfarad, 100 volt C4 .001 microfarad C5 .01 microfarad Q1 2N
3638 Triac 133 Q 20C4L3 Voltage Regulator 121 V39ZA1 NAND Gate
Circuit CD4011 ______________________________________
When it is desired to dispense beverage to fill a cup to a
pre-determined level, actuating lever 93 is activated, such as by
pushing it with the cup. This results in microswitch 113 connecting
the normally open contact 143 to logic ground. This connects the
input 6 (the numbered connections for the NAND gates 135-141 tare
the pin connections identified on the CD4011 logic chip) of NAND
gate 137 to ground through capacitor C5. This negative going signal
causes the output of NAND gate 137 at pin 4 to go to a "1" or
positive stage, which is conveyed to pin 2 of NAND gate 135. Since
microswitch 113 no longer connects pin 1 of NAND gate 135 to
ground, pin 1 also receives the positive output of NAND gate 137
through capacitor C4 and resistor R9, so that the output of NAND
gate 135 at pin 3 is a "0" or negative signal. The "0" at pin 3 is
connected to pin 5 of NAND gate 137 to hold pin 4 at the "1" output
until the circuit is reset.
The output of NAND gate 137 is inverted by NAND gates 139 and 141
and applied to the base of transistor Q1 through resistor R8. This
negative going signal triggers transistor Q1, which provides gate
current for triac 133 through resistor R6. Triac 133 is thus
switched to a closed circuit or conducting state to connect
solenoid coils 13 and 15 across terminals 117 and 119 for
energization by the AC source. Energization of solenoids 13 and 15
opens the respective valves for discharge of a beverage, such as
into cup 61.
As cup 61 fills, a spray or mist of droplets of liquid (which may
be the mixed beverage, the individual constituents, or a
combination thereof) is formed adjacent the top of the beverage
already in the cup. In the case of a carbonated beverage, the spray
or mist will be a foam produced by the carbon dioxide and droplets
of liquid.
As the cup fills to a pre-determined level, the spray, mist or foam
will create an electrically conductive path between the actuating
lever 93 and the beverage flowing into cup 61. As the quantity of
liquid droplets grows with increase of the beverage level in cup
61, the impedance of the electrically conductive path between
actuating lever 93 and the flowing beverage will decrease until a
current of a sufficient magnitude can flow to reset the flip-flop
circuit. Due to the relatively sensitive nature of the flip-flop
circuit utilized, in the preferred embodiment disclosed herein, a
current flow on the order of 5 microamperes is sufficient to
initiate the reset operation.
The relatively small current flows from the positive output at pin
4 of NAND gate 137, through the resistor R9 to actuating lever 93
and from actuating lever 93 to logic ground through the spray or
mist of liquid droplets, the flowing beverage, the metallic path to
the metallic structure 131 and capacitor C2. The current flowing
through this path to begin charging of capacitor C2 produces a
sufficiently negative going potential on pin 1 of NAND gate 135 to
change the output of the NAND gate 135 to a "1" or positive signal.
Since capacitor C5 has charged to the DC potential on terminal 125
through the resistor R11, both inputs to the NAND gate 137 are
positive, so that a "0" or negative signal is produced at the
output of NAND gate 137. Thus, the flip-flop circuit formed by NAND
gates 135 and 137 is reset, and the "0" or negative pulse on pin 4
at the output of NAND gate 137 is inverted into a positive signal
that turns off transistor Q1, which removes the gate current to
triac 133. Triac 133 is thus switches to an open circuit or
non-conducting state, so that the solenoid coils 13 and 18 are no
longer energized and the discharge of beverage is discontinued.
If the cup 61 has not been filled to the desired level, the manual
override switch 145 may be closed to connect pin 6 of NAND gate 137
to ground, which produces a negative going pulse that sets the
flip-flop formed by NAND gates 135 and 137 back to the state
required to initiate dispensing. The cycle of dispensing and
turnoff as described above is then reinitiated.
It should be understood that various modifications, changes and
variations may be made in the arrangement, operation and details of
construction of the elements disclosed herein without departing
from the spirit and scope of this invention.
* * * * *