GB2318838A

GB2318838A - Pump for dispensing viscous material

Info

Publication number: GB2318838A
Application number: GB9726142A
Authority: GB
Inventors: Robert T Topper; John W Gilliom; James M Tucker
Original assignee: White Consolidated Industries Inc
Current assignee: White Consolidated Industries Inc
Priority date: 1993-12-10
Filing date: 1994-12-02
Publication date: 1998-05-06
Anticipated expiration: 2014-12-02
Also published as: GB2318838B; GB9726139D0; GB2318837A; GB2318839A; GB9726142D0; GB2318836A; GB2318839B; GB2318837B; GB9726146D0; GB9726140D0; GB2318836B

Abstract

A reciprocating piston has coaxial inner and outer piston members 138,140 which are movable along a piston rod 78 relative to each other to act as a one-way valve. Upon movement of the piston within a cylinder 86 in a dispensing direction, material contained therein, such as ice cream or the like, is pressurised out of a dispensing nozzle 188 whilst simultaneously new material is sucked into the cylinder from a collapsible container 40. A shearing action between an inner annular surface 144 of the outer piston 140 and an outer cylindrical surface 162 of the inner piston 138 is generated as they move into sealing engagement with each other and helps to cut through or deform particulate material obstructions between the two. Upon movement in a reverse direction, the two piston members 138,140 move apart to allow the piston to pass through previously suctioned material within the cylinder. The pump may be motor driven.

Description

1 2318838 1 VISCOUS "MATERIAL DISPENSER AND METHOD FOR DISPENSING

2 BACKGROUND OF THE INVENTION

3 The present invention relates in general to devices 4 and methods for dispensing flowable materials having high viscosities, and more particularly to the dispensing of 6 soft serve frozen confections such as ice cream and the 7 like.

8 A frozen confection, such as ice cream, frozen yogurt, 9 sherbet, or sorbet, is termed "soft serve" when it is at a temperature within a range of approximately 10 to 20F, for 11 example 18OF, so as to have a viscosity that will enable it 12 to flow through a dispensing nozzle into an edible cone or 13 other suitable container whereupon the soft serve 14 confection is immediately consumed. Traditionally, complex is machines have been provided at retail outlets to 16 manufacture, store and dispense soft serve frozen 17 confections. The complexity of the machines makes them is costly not only to acquire but also to maintain, both from 19 an operational and a hygienic standpoint. Also, the quality of the soft serve confection is difficult to 21 control.due to variations in the ingredients loaded into 22 the machinef and due to variations in the level of skill of 23 the machine operators. Further, it is difficult to 24 provide, at the retail level, a wide variety of types and flavors of soft serve frozen confections since the noted 26 machines must each be dedicated to providing only a few 27 types and flavors of confections at any given time, and 28 since the number of machines per retail outlet is limited 29 by cost and space considerations.

As an alternative to the above, it has been proposed 31 that soft serve frozen confections be manufactured at a 32 central facility, and then stored at the facility in 33 portable containers at a low storage temperature of CF or 1 below. By use of a central manufacturing and storage 2 facility, the cost and quality of the frozen confections 3 could be more readily controlled. Also, an inventory of 4 prefilled containers providing a wide range of types and flavors of frozen confections could be established. The 6 containers could then be shipped on demand from inventory 7 to retail outlets wherein they would be thawed or tempered 8 to a "soft serve" temperature. The containerized soft 9 serve frozen confections could then be dispensed at the retail outlet from a simpler and more compact machine that 11 would only function as a dispenser and storage means.

12 Examples of dispensers for containerized soft serve 13 confections are illustrated by U.S. Patents 5,048,724, 14 5,069,364, 5,215,222, and 5,244,277, all of which are expressly incorporated herein. The noted patents disclose 16 dispensers wherein collapsible or otherwise deformable 17 containers are mechanically compressed to expel or extrude 18 soft serve frozen confections therefrom for each individual 19 serving. While the noted compression type soft serve dispensers arguably represent an advance in the art, it has 21 been found that repeated compression of soft serve frozen 22 confections, which can contain up to 4o air, may degrade 23 the quality of the dispensed product. It is believed that 24 repeated pressurization of the frozen confection within the container causes undesirable ice crystals to form within 26 the confection, degrading the taste and texture of the 27 dispensed confection. Although this effect is small or 28 almost negligible for each pressurization/depressurization 29 cycle, since the entire volume of confection within the containers of these patents is repeatedly pressurized the 31 cumulative effect is substantial and noticeable.

32 Also, the discharge rate from the earlier noted 33 patented devices, which mechanically compress the product, 34 is highly dependent upon product viscosity and, therefore, product formulation and temperature. For example, high fat 36 content chocolate ice cream having a relatively high 1 viscosity may have to be dispensed at a higher "soft serve" 2 temperature, or a higher pressure, than a lower viscosity 3 sorbet.

4 It is therefore an object of the present invention to provide a dispenser for containerized frozen confections 6 and the like of the soft serve type that can operate over a 7 relatively wide "soft serve" temperature range wherein 8 frozen confections at the same temperature, but of 9 substantially different viscosities can be dispensed. It is a further object of the present invention to provide a 11 dispenser that will eliminate repeated compression or 12 pressurization of the frozen confection within the 13 container, and minimize compression or pressurization of 14 dispensed frozen confection, so as to avoid or at least iS minimize the above noted problems associated therewith. It 16 is also an object of the invention to provide a dispenser 17 that will dispense ice cream in controlled predetermined 18 amounts for purposes of portion control. It is a further 19 object of the invention to provide a delivery means including a dispensing valve which is operable to dispense 21 viscous material with a minimum of compression or 22 pressurization of the viscous material being dispensed 23 therefrom.

24 It is to be noted that while the above background and subsequent description of the invention focus mainly on the

26 dispensing of soft serve frozen confections, it is clearly 27 contemplated by the inventors that the invention may have 28 applications to the dispensing of other high viscous food 29 products, such as prepared vegetables and nutritional supplements.

1 SUMMARY OF THE INVENTION

2 In accordance with the present invention, a dispenser 3 for viscous material such as ice cream and the like 4 preferably includes a supply source of viscous material constituted by a portable container for storing the viscous 6 material. The dispenser also includes a delivery means for 7 discharging the viscous material, and a pump means 8 connected between the supply source and the delivery means 9 to establish fluid communication therebetween.

The pump means includes a pump member which is 11 reciprocally movable in two directions. When the pump 12 member moves in the first of its two directions, it 13 pressurizes the viscous material to thereby push the 14 material toward the delivery means for discharge thereof 15 and to simultaneously extract viscous material from the 16 supply source by means of suction. The pump member is 17 movable in the second or opposite of its two directions is without causing substantial movement of the viscous 19 material relative to the delivery means or the supply 20 source.

21 In further accordance with the present invention, a 22 dispenser is provided which is operable to dispense 23 containerized frozen confections and the like of the soft- 24 serve type over a relatively wide temperature and viscosity range. The dispenser utilizes a positive displacement pump 26 that dispenses predetermined quantities of confection with 27 minimal compression of the confection being dispensed, and 28 eliminates compression of the confection in the container, 29 thereby avoiding or at least minimizing the problems, e-g ice crystal formation, present in the prior art dispensing

31 methods.

32 In further accordance with the present invention, the 33 delivery means includes a dispensing valve for discharging 34 viscous material. The dispensing valve includes a valve 35 body which provides an inlet port, an outlet port, and a 1 chamber in.fluid communication with said ports. The 2 viscous material flows from the inlet port to the outlet 3 port via the chamber when the valve is in an open 4 condition.

The dispensing valve further comprises a poppet member 6 contained within the valve body and movable between a 7 closed position when seated and sealed against the outlet 8 port, and an open position when unseated and spaced from 9 said outlet port. When in the seated and sealed position, the poppet member precludes the flow of viscous material 11 out of the outlet port. when in the open position, the 12 poppet member permits the flow of viscous material out of 13 the outlet port.

14 The poppet member provides a surface which is acted upon by the pressurized viscous material within said 16 chamber. The dispensing valve also includes a biasing 17 means? e.g. a compression spring, which biases the poppet 18 member toward its closed position. The poppet member is 19 movable to its open position against the bias force of the biasing means solely by viscous material pressure which is 21 created by movement of the pump member in the first of its 22 two directions. Movement of the poppet member to its 23 closed position is a result of the combination of the 24 biasing force and a transient reduced pressure condition or suction force developed within the chamber by the pump 26 means during movement of the pump member in the second of 27 its two direction.

1 BRIEF DESCRIPTION OF THE DRAWINGS

2 These and further features of the present invention 3 will be apparent with reference to the following 4 description and drawings, wherein:

FIG. 1 is a front perspective view of a dispenser 6 according to the present invention; 7 FIG. 2 is a side elevational view, in cross-section, 8 of the dispenser of FIG. 1; 9 FIG. 3 is a side elevational view, in cross-section, of a dispensing pump, a portable container and a delivery 11 means in accordance with the present invention; 12 FIGS. 4A-4D show the dispensing pump and delivery 13 means of FIG. 3 in various sequential operating conditions; 14 FIG. 5 is a front exploded perspective view of the pump and dispensing valve; 16 FIG. 6 is a top plan view of a rack mounting block and 17 rack according to the present invention; 18 FIG. 7 is a rear elevational view of a discharge 19 cylinder of the delivery means according to the present invention; 21 FIG. 8 is a front elevational view of a conduit member 22 of the dispensing pump according to the present invention; 23 FIG. 9A is a front elevational view of an alternative 24 portable container according to the present invention; FIG. 9B is a front elevational view of another 26 alternative portable container according to the present 27 invention; 28 FIG. 9C is a front elevational view of a further 29 alternative portable container according to the present invention.

1 DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

2 A dispenser according to the present invention is 3 generally illustrated in FIGS. 1 and 2, and includes a 4 thermally insulated dispensing cabinet 10 having opposed vertical side walls 12 (one shown), horizontal top and 6 bottom walls 14 and 16, and a vertical rear wall 18. The 7 bottom wall 16 is spaced from a supporting surface by a 8 base member 20 which houses various components, such as a 9 conventional refrigeration compressor (not shown) and a conventional condenser structure (not shown). A front 11 portion of the cabinet 10 provides spaced upper and lower 12 openings 22, 24 which are separated by an inset panel 26, 13 the openings 22, 24 being closed by upper and lower doors 14 28, 30 which are preferably mounted for pivotal movement about their left edge using appropriate hinge structures, 16 as illustrated most clearly in FIG. 1. A drip pan 31 is 17 provided above the lower door 30 and is removably attached is to the lower end of inset panel 26, as illustrated.

19 The upper door 28 provides control devices, such as push buttons 32 (one for each of the two dispensing pump 21 means to be subsequently illustrated), to control 22 dispensing of frozen confection, and one or more inside 23 recesses or pockets 34 which receive and thermally insulate 24 frozen confection delivery means, as will be described more fully hereafter. The panel 26, walls 12, 14f 16, and 18, 26 and doors 28 and 30 of the dispensing cabinet 10 are 27 thermally insulated to reduce the energy required to 28 maintain the temperature provided in the interior of the 29 cabinet, which is typically between about 10 to 200F.

Figure 2 shows that the interior of the dispensing 31 cabinet 10 is generally divided into upper and lower 32 compartments or sections 36 and 38. The lower section 38 33 serves as a storage and temperature conditioning 34 (tempering) cabinet whereby the temperature of a plurality of portable containers 40 of frozen confection, which hold -a- 1 between about two to five gallons of frozen confection and 2 are typically introduced into the tempering cabinet at a 3 temperature of about OOF or below, slowly rises to a 4 dispensing temperature of between about 10 to 20OF over an extended period of time, generally between about twelve and 6 thirty-six hours. After the frozen confection within a 7 particular container 40 is tempered or brought to the 8 dispensing temperature, that particular container is ready 9 to be placed in the upper section 36 and the confection dispensed therefrom upon demand.

11 The lower section 38 also houses refrigeration 12 equipment including an evaporator structure 42 and a 13 plurality of fans 44 that work in conjunction with the 14 compressor and condenser structure housed within the base member 20 in the conventional manner as is known in the 16 art. The fans 44 are operable to circulate relatively 17 warmer air from the upper and lower sections 36, 38 of the 18 dispensing cabinet 10 past the evaporator 42 and to 19 circulate relatively colder air throughout the dispensing cabinet 10 as a result of the evaporators cooling effect.

21 Temperature within the sections 36, 38 is preferably 22 controlled by introducing electrical heat via resistance 23 type heating elements (not shown) in response to control 24 signals provided by a proportional temperature controller (not shown), as is known in the art, to offset the cooling 26 capacity of the refrigeration equipment and thus maintain 27 the temperature within the upper and lower sections within 28 a predetermined range, i.e. the dispensing or "soft serve" 29 temperature. Naturally, any number of known equivalent temperature maintenance systems can be used without 31 departing from the scope of the present invention.

32 For reasons of cleanliness, the upper section 36 is 33 preferably separated by a dividing partition or wall 46 34 into front and rear regions 48 and 50. The rear region 50 houses a reversible motor 52, which preferably operates on 36 standard 120V# 60 Hz power, and a gear reduction unit 54.

1 The front region 48 houses a dispensing pump means 56, 2 which will be described hereafter.

3 A sliding rack 58, which is preferably enclosed by a 4 flexible bellows 60, extends through an opening in the dividing wall 46 and operably connects the motor 52 to the 6 dispensing pump means 56 via the gear reduction unit 54.

7 FIG. 6 shows that the sliding rack 58 is movably mounted 8 for.reciprocating motion within a groove or channel 62 in a 9 mounting block 64 beneath the motor 52 and provides a series of lengthwise extending teeth 66 which mesh with a 11 pinion gear 68 provided by the gear reduction unit 54 (see 12 FIG. 2). As the motor 52 is operated in a first mode or 13 direction, the rack 58 is moved in a corresponding first 14 direction by the pinion gear 68. Similarly, when the motor 52 is reversed to operate in a second mode or direction the 16 rack 58 is moved in an opposite or second direction by the 17 pinion gear 68. As such, the rack 58 and dispensing pump is means 56, which are connected together as will be 19 subsequently illustrated, are reciprocally operated.

Within the mounting block 64 are provided limit 21 switches 70 and 72 which, as the rack 58 travels back-and 22 forth, sense the position of a notch 73 in the rack 58 and 23 control the operation of the motor 52 accordingly. More 24 specifically, position-relative signals provided by the limit switches 70 and 72 are used to control when the motor 26 52 is reversed to operate in the second mode or direction 27 and to turn the motor off when a complete dispensing cycle 28 has been completed. As the motor is operated in the first 29 mode or direction, and the limit switch 70 engages the notch 73. the motor 52 will be reversed to operate in the 31 second mode or direction. When the limit switch 72 engages 32 the notch 73 the motor 52 will be turned off. By provision 33 of additional notches in the rack, a number of different 34 rack travel or stroke lengths, and a corresponding number of different volumes of dispensed frozen confection (i.e., 36 4 oz., 6 oz., 8 oz.), can be provided.

1 Alternatively, the limit switches 70, 72 could be 2 replaced by an optical encoder which would count the number 3 of revolutions of a motor shaft (not shown) or the pinion 4 gear 68 and control the motor 52 such that a predetermined volume of material is dispensed. Other alternatives 6 include a timer means which would measure the time period 7 of motor operation in each direction corresponding to a 8 predetermined volume of dispensed material or a stepper 9 motor under microprocessor control which would track and control the position of a pump piston and, therefore, the 11 volume of dispensed material. Other equivalent control 12 means and methods could also be provided without departing 13 from the scope of the present invention.

J 14 With continuing reference to FIG. 2, and also to FIGS.

3-8, a terminal end 74 of the rack 58 is pinned or 16 otherwise attached to a connector 76 which releasably 17 receives a piston rod 78 provided by the dispensing pump is means 56. In the illustrated and preferred embodiment a 19 spring clip 80 releasably attaches the piston rod 78 to the connector 76 to aid in quick assembly and disassembly of 21 the dispensing pump means 56 for cleaning or maintenance.

22 Any number of equivalent attachment means can be 23 substituted for this arrangement without departing from the 24 scope of the present invention.

The dispensing pump means 56 comprises a dispensing 26 pump 82 and delivery means 84. Although two such 27 dispensing pump means 56 are contained within the cabinet 28 10 of the illustrated and preferred embodiment, it is 29 anticipated that the size and number of dispensing pumps 82, delivery means 84, and containers 40 will vary 31 depending upon the anticipated volume of frozen confection 32 to be served, and the number of flavors or types of 33 confections desired to be dispensed at any given time.

34 The dispensing pump 82 provides a conduit member or pump cylinder 86 and the delivery means 84 provides a 36 discharge cylinder 88. The conduit member 86 and discharge 1 cylinder 88. are removably connected to one another by 2 connector means 89, as will be described more fully 3 hereafter. The conduit member 86 serially connects the 4 container 40 and the delivery means 84 and has a first or rear end which is closed by a removable plug-like end wall 6 member 90 and an opposite front or second end having an 7 integral end wall 92. A cylindrical outlet spout or male 8 connection 94 projects outwardly from the second end of the 9 conduit member 86 and provides a pair of annular, axially spaced apart ribs 96 and a series of radially extending 11 mounting tabs 98 (FIGS. 5 and 8). The annular ribs 96 12 define a groove therebetween for receipt of an 0-ring 100, 13 while the tabs 98 are adapted to be received by an inlet or 14 female mounting portion 102 of the discharge cylinder 88 in is a twist-and-lock fashion, as will be apparent from the 16 discussion to follow. The outlet spout 94, which defines a 17 conduit member outlet port 104, and the conduit member 86 18 are generally coaxial, with the outlet spout 94 having a 19 smaller diameter than the conduit member 86.

Near the rear or first end of the conduit member 86 is 21 provided an inlet port 106. The inlet port 106 includes an 22 upwardly extending inlet spout 108 with which the container 23 40 communicates. In the preferred embodiment, a container 24 adapter and mounting member 110 is provided to secure and support the container 40 on the inlet spout 108 of the 26 conduit member 86.

27 As is best shown in FIG. 3, the adapter member 110 28 provides a downwardly extending, centrally located, 29 cylindrical member 112 which receives the inlet spout 108, an upwardly extending cylindrical member 114 which projects 31 into a lower end of the container 40, and a ring shaped 32 body member 116. An outer peripheral portion 118 of the 33 body m er 116 receives and vertically supports a lower 34 peripheral edge of the container 40, as illustrated.

The inlet spout 108 abuts an annular surface or stop 36 119of the adapter 110 to limit insertion or travel of the 1 spout 108 into the downwardly extending cylindrical member 2 112. Preferably, the downwardly extending cylindrical 3 member 112 of the adapter 110 is permanently attached to 4 the inlet spout 108 by adhesives, ultrasonic welding, or the like. Alternatively, the adapter member 110 could be 6 integrally formed with the conduit member 86. Further, the 7 adapter 110 can be removably secured to the inlet spout 108 8 by.a threaded connection or other means to allow the 9 adapter member 110 to be replaced by another adapter member designed to receive a different container having, for 11 example, a larger or smaller diameter than the illustrated 12 container 40.

13 The upwardly extending cylindrical member 114 is 14 preferably resilient and radially deformed inwardly as it is received by the container 40 to seal the engagement 16 therebetween in a fluid-tight manner. An annular rib 120 17 is provided on the outer surface of the upwardly extending 18 cylindrical m er 114 to further seal the adapter member 19 110 on the container 40. Alternatively, the upwardly extending cylindrical member 114 could be formed of a more 21 radially stiff material and provided with an 0-ring or 22 other appropriate sealing means to sealably secure the 23 container 40 to the adapter 110. Also, the container 40 24 could provided a threaded spout which could be threadably received by the upwardly extending cylindrical member 114 26 having mating threads.

27 From the foregoing it should be clear that the adapter 28 member 110 described herein is specially designed for 29 receipt of the preferred and illustrated container 40.

since the dispensing pump means 56 is adapted for use with 31 various types of containerst some of which are illustrated 32 hereinafter in FIGS. 9A-9C, the present invention is not to 33 be limited to the specific adapter member 110 or container 34 40 disclosed herein. Rather, it is anticipated that the adapter member 110 will be interchangeable with various 1 other equivalent adapter members for supporting and 2 mounting various other containers.

3 Adjacent the inlet port 106, the rear or first end of 4 the conduit member 86 provides a groove for threadably receiving threads 122 provided by the end wall member 90 to 6 releasably secure the end wall member 90 thereto. The 7 threads 122 engage an annular terminal or outer surface 123 8 of the conduit member 86 to limit insertion or travel of 9 the end wall member 90 into the conduit member (see FIGS. 3 and 5). The end wall member 90 is generally cylindrical, 11 and has a cut-away top portion 124 which aligns with the 12 inlet port 106 when the threads 122 engage the outer 13 surface 123 of the conduit member 86 to thereby allow 14 viscous material to be freely introduced into the conduit is member 86, as illustrated in FIGS. 3 and 5. The end wall 16 member 90 has a cylindrical outer surface 126 which, with 17 the aid of an 0-ring 128, sealingly engages the inner 18 circumference of the conduit member 86 adjacent the inlet 19 port 106, as illustrated. A pair of gripping tabs 130 extend from the end wall member 90 to allow a user to 21 rotate the end wall member 90 for installation and removal 22 thereof.

23 A central circular hole 132 (FIG. 5) is provided in 24 the end wall member 90 through which the piston rod 78 slidably extends. A circular groove surrounds the circular 26 hole 132 and receives an 0-ring 134 which slidably seals 27 the engagement of the end wall member 90 and the piston rod 28 78. Thus, the end wall member 90 seals the rear or first 29 end of the conduit member 86 while allowing the piston rod 78 to move reciprocally and axially relative to the conduit 31 member 86. While the preferred end wall member 90 is 32 illustrated in the drawings and described hereinabove, it 33 should be clear that various other means could be 34 substituted for the illustrated end wall member 90 without departing from the scope of the present invention.

1 The dispensing pump 82 comprises an assembly including 2 a pump member or valved piston 136 (see FIG. 5) in addition 3 to the piston rod 78, conduit member 86 and the end wall 4 member 90. The piston 136 has coaxial inner and outer piston members 138 and 140 which are axially movable along 6 the piston rod 78 relative to one another in a telescoping 7 manner. As will be described more fully hereafter, there 8 is -lost motion between the inner and outer piston members 9 138, 140 to allow the inner piston member 138 to move relative to the outer piston member 140 during operation of 11 the dispensing pump 82.

12 The outer piston member 140 includes a series of arms 13 142 that extend radially inwardly from an inner annular 14 surface 144 to a central hub 146 (see FIG. 5). A flow path for viscous material is defined by the hollow or open area 16 between the hub 146, arms 142, and inner annular surface 17 144. The hub 146 is formed of a resilient plastic and 18 defines a slot-like snap-on, snap-off, U-shaped opening 148 19 for releasably receiving a reduced diameter portion or extension 78a of the piston rod 78. Preferably, the open 21 end of the U-shaped opening 148 is slightly smaller than 22 the diameter of the piston rod 78, causing the arms of the 23 "U" to outwardly deform and releasably snap the piston rod 24 78 into place during assembly. Snap-fitting the outer piston member 140 on the reduced diameter portion 78a of 26 the piston rod 78 facilitates assembly and disassembly of 27 the dispensing pump means 56 for cleaning. The reduced 28 diameter portion 78a of the piston rod 78 provides a 29 terminal knob or button 150 to retain the outer piston member 140 thereon. The knob or button 150 is sized to 31 allow its insertion between the arms 142 during assembly of 32 the piston rod 78 on the outer piston member 140.

33 The outer piston member 140 also provides an outer 34 cylindrical surface 152 and forward and rearward facing annular surfaces 154 and 156 (see FIG. 3). The rearward 36 facing annular surface 156 is radially contoured or 1 beveled, as illustrated, to direct or funnel viscous 2 material into the hollow interior portion of the outer 3 piston member 140. The forward annular surface 154 is 4 generally planar. The outer cylindrical surface 152 is designed to slide adjacent the inner surface of the conduit 6 member 86. A relatively forward end of the outer 7 cylindrical surface 152 provides an annular groove for 8 receipt of an 0-ring 158 which seals the interface between 9 the outer piston member 140 and the conduit member 86.

More specifically, the 0-ring 158 slidably and sealably 11 engages the inner surface of the conduit member 86.

12 The inner piston member 138 has an outer cylindrical 13 surface 162, forward and rearward-facing surfaces 163, 164, 14 and a centrally located threaded bore 166. The threaded bore 166 allows the inner piston member 138 to be 16 threadably and removably secured to the piston rod 78. The 17 outer cylindrical surface 162, which slidably mates with is the inner annular surface 144 of the outer piston member 19 140, has formed therein an annular or circumferential groove for receipt of an 0-ring 168 which seals the 21 engagement of the outer cylindrical surface 162 with the 22 inner annular surface 144 of the outer piston member 140.

23 As will be described more fully with regard to operation of 24 the dispensing pump 82, when the inner piston member 138 moves into sealing engagement with the outer piston member 26 140 there is, in accordance with the present invention, a 27 shearing action between the mating surfaces provided by the 28 inner annular surface 144 of the outer pistonmember 140 29 and the outer cylindrical surface 162 of the inner piston member 138. The shearing action or interface area created 31 at the mating surfaces helps to remove or shear particulate 32 material, such as nuts and fruit, from the area of sealing 33 engagement between inner and outer piston members 138 and 34 140, thereby insuring sealing engagement between the inner and outer piston members.

1 Thus, the inner piston member 138 is fixed to the 2 piston rod 78 and cannot move relative thereto during 3 operation of the dispensing pump 82 while the outer piston 4 member 140 is removably and slidably secured to the piston rod 78 and has a limited range of axial motion relative to 6 the inner piston member 138. In the illustrated 7 embodiment, movement of the inner piston member 138 8 relative to the outer piston member 140 (i.e., the lost 9 motion) is limited to the distance between the button or knob 150 on the piston rod 78 and the forward facing 11 surface 163 of the inner piston member 138, less the 12 thickness of the hub 146.

13 The dispensing pump 82 is assembled outside of the 14 conduit member 86 by snap fitting the reduced diameter portion 78a of the piston rod 78, which already has the 16 inner piston member 138 threadably secured thereto, to the 17 hub 146 of the outer piston member 140. The piston 136 is is inserted into the rear or first end of the conduit member 19 86 and the end wall member 90 is pushed onto the piston rod 78 and threadably secured to the conduit member 86.

21 The dispensing pump 82 is placed in the front region 22 48 (see FIG. 2) of the cabinet 10 such that the end of the 23 piston rod 78 extends into the connector 76 and is 24 attached, via the connector 76 and spring clip 80, to the rack 58 as discussed earlier. The conduit member 86 26 provides exterior mounting projections 170 (see FIG. 5) 27 which are secured to a cabinet-provided support surface 28 (not shown) by conventional fasteners such as thumb screws 29 (not shown) to complete installation of the dispensing PUMP 82 within the cabinet 10.

31 With reference to FIGS. 3 and 7, the mounting portion 32 102 of the discharge cylinder 88 has a cylindrical body 174 33 including an outer end with inner and outer annular 34 retaining walls 176, 178, a discontinuous clover-shaped annular groove 180, and a series of stop surfaces 182. The 36 stop surfaces 182 are provided between the inner and outer 1 retaining walls 176, 178, and form the discontinuities in 2 the annular groove 180. Radial notches 184 are provided in 3 the outer retaining wall 178 to receive the mounting tabs 4 98 of the conduit member outlet spout 94. During assembly, and with the conduit member 86 of the dispensing pump 82 6 fixed in position within the cabinet 10, the inlet or 7 female mounting portion 102 of the discharge cylinder 88 is 8 positioned relative to the male connection or outlet spout 9 94 such that the cylindrical body 174 slidably receives the male connection or outlet spout 94 and the mounting tabs 98 11 are received by the notches 184 in the outer retaining wall 12 178. Thereafter, the discharge cylinder 88 is rotated 13 counterclockwise, causing the mounting tabs 98 to slide 14 into the annular groove 180 between the inner and outer retaining walls 176, 178, with rotation being limited by 16 the stop surfaces 182 such that the discharge cylinder 88 17 is generally vertically oriented, as illustrated. The 0 is ring 100 provided on the outlet spout 94 slidably engages 19 the inner wall of the cylindrical body 174 to seal the union of the female mounting portion 102 and the male 21 connection or outlet spout 94.

22 In addition to the inlet or mounting portion 102, the 23 discharge cylinder 88 includes a hollow main body 186 and a 24 reduced-diameter lower cylindrical extension or nozzle 188.

The inlet or mounting portion 102 projects from the main 26 body 186 and serves as a valve inlet port thereto. The 27 main body 186 and nozzle 188 receive a piston-like poppet 28 member 190 that is reciprocally movable within the 29 discharge cylinder 88 and serves as a delivery valve for viscous material from the conduit member 86 toward and 31 through an outlet provided at a lower end of the nozzle 32 188. A side of the main body 186 remote from the inlet or 33 mounting portion 102 generally matches the shape of the 34 poppet member 190 while a side proximate to the mounting portion 102 is scooped-out to allow viscous material to 36 enter the discharge cylinder 88, as illustrated. An 1 annular shoulder surface 192 surrounds an upper end of the 2 nozzle 188 and serves as a seat against which the poppet 3 member 190 seals.

4 The outer surface of the discharge cylinder 88 provides a pair of lugs or ears 194 which are adapted to be 6 releasably received by slotted openings 196 (FIG. 5) in a 7 cap 198 which is part of the delivery means 84. Although 8 the-cap 198 is preferably attached to the main body 186 9 with a bayonet-type connection as illustrated, it should be clear that threads or other suitable attachment means could 11 be employed without departing from the scope of the present 12 invention. The cap 198 includes projections 200 to 13 facilitate user-rotation thereof during assembly and 14 disassembly of the deliver means 84 for cleaning and is maintenance and a vent hole 199 (FIG. 5).

16 The delivery means 84 includes a compression or coil 17 type biasing spring 202 in addition to the poppet member 18 190, discharge cylinder 88, and cap 198. The poppet member 19 190 is slidably received within the discharge cylinder 88 and provides an enlarged diameter upper portion 204 and a 21 reduced diameter lower portion 206. The upper portion 204 22 provides an annular groove for receipt of an 0-ring 208 23 which slidably seals against the inner surface of the main 24 body 186 at a location upwardly spaced from the mounting portion 102 providing the valve inlet port. The lower 26 portion 206 provides an annular groove within which an 0 27 ring 210 is received, as illustrated. The 0-ring 210 is 28 provided to seal or seat against the annular shoulder 29 surface 192 thereby closing the valve. A frustoconical transition surface 212 is provided intermediate the upper 31 and lower portions 204 and 206 of the poppet member 190.

32 The transition surface 212 serves as a surface against 33 which the force of pressurized viscous material bears and 34 forces the poppet member 190 upwardly, as will be described more fully hereafter.

1 The lower portion 206 of the poppet member 190 has a 2 closed bottom end 214 (see FIG. 3) and is slidably received 3 within the nozzle 188. As the poppet member 190 moves 4 downwardly in the discharge cylinder 88, there is a shearing action between edge portions provided by an outer 6 surface of the lower portion 206 of the poppet member 190 7 and the inner surface of the nozzle 188 to help remove 8 particulate matter, such as nuts or fruit, from the nozzle 9 188.

The upper portion 204 of the poppet member 190 11 provides a cup shaped interior having an upstanding 12 cylindrical member 216 which receives a lower end 218 of 13 the spring 202. An upper end 220 of the spring 202 is 14 received by a cylindrical member 222 which projects downwardly from the center of the cap 198.

16 The delivery means 84 is assembled by sliding the 17 poppet member 190 downwardly into the discharge cylinder is 88. Thereafter, the upper end 220 of the coil spring 202 19 is placed over the cylindrical member 222 of the cap 198, and the cap is placed over the open top end of main body 21 186 of the discharge cylinder 88 such that the lower end 22 218 of the spring 202 is received by the upstanding 23 cylindrical member 216 of the poppet 190. The cap 198 is 24 secured to the discharge cylinder 88 by pushing downwardly to compress the spring 202 and then rotating the cap 198 to 26 allow the lugs 194 provided by the discharge cylinder 88 to 27 be received within the slotted openings 196 of the cap 198.

28 At this point the oring 210 on the lower portion 206 of 29 the poppet member 190 is seated on the annular shoulder surface 192 due to the bias of the compressed spring 202 31 and the 0-ring 208 of the upper member 204 is in sealing 32 engagement with the inner surface of the main body 186 at a 33 location upwardly spaced from the inlet port or mounting 34 portion 102 as illustrated in FIG. 3. Thereafter the discharge cylinder 88 is attached to the conduit member 86 36 as described hereinbefore.

1 With the dispensing pump means 56 assembled and a 2 container 40 of viscous material, such as frozen 3 confection, placed and sealed upon the inlet spout 108, 4 dispensing of viscous material is ready to begin.

Initially, the conduit member 86 is charged or primed with 6 viscous material from the container 40 by operating the 7 dispensing pump means 56 through one or more cycles, as 8 wil.1 be described hereafter, to introduce or fill the 9 conduit member 86 with viscous material. As noted 10 hereinbefore, positioning of the piston 136 within the 11 conduit member 86 is controlled by the rack 58 and motor 52 12 in response to signals from the limit switches 70 and 72.

13 The dispensing pump means 56 is generally in the 14 configuration shown in FIG. 4A at the start of a dispensing 15 cycle wherein chambers A and B in front of and behind the 16 piston 136, respectively, are fully charged with viscous 17 material. Manipulation of the control devices or push is buttons 32 (see FIG. 1) operates the motor 52 in a first 19 mode or direction in which the pinion gear 68 drives the rack 58 and associated piston rod 78 leftwardly (as shown 21 in FIG. 4A) through the conduit member 86. Since the outer 22 piston member 140 is in sealing engagement with the conduit 23 member 86 and is slidably mounted on the reduced diameter 24 portion 78a of the piston rod 78, there is lost motion between the inner and outer piston members 138, 140, and 26 the inner piston member 138 moves toward and into sealing 27 engagement with the outer piston member 140 (FIG. 4B). As 28 such, the inner and outer piston members 138 and 140 are in 29 sealing engagement with each other and are prepared to move 30 together down the conduit member 86 toward the integral end 31 wall 92.

32. As the piston 136 moves along the inner surface of the 33 conduit member 86, the viscous material in region A in 34 front of the piston 136 is pressurized and therefore pushed 35 or pumped toward the outlet port 104 while a vacuum or low 36 pressure condition is simultaneously developed in region B 1 behind the piston 136. The vacuum or low pressure 2 condition created in the conduit member 86 suctions or 3 evacuates viscous material from the container 40 into 4 region B behind the piston 136.

The pushed or pumped viscous material flows through 6 the outlet port 104 and into the main body 186 of the 7 discharge cylinder 88, below the transition surface 212 of 8 the poppet member 190. The pressurized or pumped viscous 9 material provided by movement of the piston 136 bears against the transition surface 212 and forces the poppet 11 member 190 to move upwardly against the bias of the spring 12 202, thereby unseating the 0-ring 210 from the shoulder 13 surface 192 and thus allowing viscous material within the 14 discharge cylinder 88 to be dispensed from the cylindrical is extension or nozzle 188.

16 At the end of a discharging or dispensing stroke, the 17 dispensing pump means 56 is generally positioned as shown is in FIG. 4C. Although the piston 136 is no longer pushing 19 or pumping viscous material out of the nozzle 188, the poppet member 190 of the delivery means 56 does not return 21 to its sealing position because the spring bias of the 22 spring 202 is preferably not strong enough to force the 23 viscous material remaining within the discharge cylinder 88 24 out of the nozzle 188. Naturally, the spring strength could be chosen such that the spring 202 would force the 26 poppet member 190 to seat on the shoulder surface 192 at 27 the end of the discharge stroke.

28 However, increasing the spring strength would also 29 increase the pressure necessary to overcome the spring bias and unseat the poppet member 190 from the shoulder surface 31 192 during the discharge stroke and would correspondingly 32 increase the energy required to dispense viscous material 33 from the region A toward an amount comparable to the energy 34 expended in suctioning or evacuating viscous material out of the container 40 and into region B. In the preferred 36 and illustrated embodiment it is desired that the energy 1 required to push or pump the viscous material from region A 2 out of nozzle 188 be relatively small or minimal as 3 compared with the energy expended in suctioning or 4 evacuating viscous material out of the container 40 and into region B of the conduit member 86. Moreover, 6 increasing the spring strength may result in an unwanted 7 high velocity burst or discharge of viscous material from 8 the'nozzle 188. Also, if a higher strength spring is 9 employed, the poppet member 190 may only move upwardly relative to the shoulder surface 192 a short distance and 11 therefore act as a strainer to restrict or prevent 12 dispensing of solid particulates, such as nuts and fruit, 13 through the nozzle 188. Furthermore, the use of a higher 14 strength spring will result in additional compression or is pressurization of the viscous material to be dispensed, 16 which may lead to undesirable ice crystal formation, as 17 discussed earlier.

is As the motor 52 is reversed to operate in a second 19 mode or reverse direction due to signals from the limit switch 70, the outer piston member 14o remains stationary 21 due to its sealing engagement with the conduit member 86 22 and the slidable mounting of the outer piston member 140 on 23 the reduced diameter portion 78a of the piston rod while 24 the inner piston member 138 moves rearwardly relative to the out er piston member 140. As the inner piston member 26 138 moves rearwardly relative to the outer piston member 27 140, the 0-ring 168 slides across the inner annular surface 28 144 of the outer piston member 140 and produces a vacuum or 29 reduced pressure condition in region A and discharge cylinder 88. The transient vacuum or suction force thus 31 created tends to draw a small amount viscous material 32 within the cylindrical extension or nozzle 188 back into 33 the main body 186 and cooperates with the spring 202 to 34 return the poppet member 190 to the sealing or seated condition illustrated in FIG. 4D.

1 Further rearward movement of the piston rod 78 causes 2 the piston 136 to be configured as shown in FIG. 4D wherein 3 the inner and outer piston members 138 and 140 are spaced 4 from each other and the terminal knob or button 150 is in contact with the hub 146 and forces the outer piston member 6 140 to move rearwardly with the piston rod 78 and inner 7 piston member 138. As the piston 136 is pulled through the 8 viscous material which had previously been drawn or 9 suctioned into region B by the piston 136 during the discharge or dispensing stroke, the inwardly-directed 11 contour of the rearward annular surface 156 funnels or 12 directs viscous material into the open interior of the 13 outer piston member 140 wherein it flows past the arms 142 14 and hub 146 and into region A at the forward side of the piston 136. As such, the inner piston member 138 acts as a 16 valve mechanism to allow the piston 136 to pass through the 17 viscous material without causing substantial movement of 18 the viscous material through the conduit member 86 in the 19 rearward direction. Movement of the viscous material past the inner piston member 138 and through the outer piston 21 member 140 homogenizes or stirs the viscous material, so as 22. to enhance the consistency and texture of the dispensed 23 product. When the piston 136 reaches the terminal position 24 illustrated in FIG. 4A at the completion of a dispensing cycle, the limit switch 72 engages the notch 73 and turns 26 the motor 52 off (see FIG. 6).

27 As the dispensing pump means 56 is operated through 28 each of a number of dispensing cycles, viscous material is 29 dispensed upon demand from the container 40 and the container collapses or otherwise deforms and thereby, in 31 effect. reduces its internal volume available for holding 32 viscous material. The container illustrated in..FIGS. 2-4D 33 provides a cylindrical outer wall 237, rigid fixed top and 34 bottom end walls 238, 239 and an inner flexible bag 240, The cylindrical outer wall is preferably formed of card 36 board or the like while the end walls 238, 239 are 1 preferably formed of plastic or stainless steel. The bag 2 240, which is preferably formed of a flexible plastic, is 3 preferably secured at a midpoint thereof to the interior of 4 the cylindrical outer wall 237 to help insure that the bag 240 properly collapses toward the inlet spout 108 during 6 evacuation of viscous material from the container 40. The 7 closed end of the flexible bag 240 has secured thereto a 8 stiff or rigid disc 241, preferably of plastic, which moves 9 downwardly with the bag 240 as viscous material is evacuated therefrom and prevents the closed end of the bag 11 240 from being suctioned into the inlet spout 108 by 12 operation of the dispensing pump 82. The open end of the 13 bag 240 is crimped together with the bottom end wall 239 to 14 the lower edge of the cylindrical outer wall 237, as illustrated best in FIGS. 3-4D. Naturally, other means of 16 sealably connecting the bag 240 to the bottom end wall 239 17 and the outer wall 237 are known in the art and could be is employed.

19 Alternatively, with reference to FIG..9A, a container 400 which comprises a coiled wire or spring member 232 21 trapped between inner and outer cylindrical plastic layers 22 234, 236, could be used in place of the container 40. One 23 or more turns of coiled wire is provided at the top and 24 bottom ends of the container 40f to help stiffen the ends.

Another alternative container 4011 is shown in FIG. 9B 26 provides a rigid cylindrical outer wall 224, rigid top and 27 bottom fixed end walls 226 and 228, and an axially movable 28 piston 230. The piston 230 is generally disc-shaped and is 29 located above the viscous material to be dispensed and moves downwardly with the material as it is drawn or 31 suctioned toward the inlet spout 108 by operation of the 32 dispensing pump means 56. For a more detailed.description

33 of the container 40, see U.S. Patent No. 5,244,277, which 34 has previously been incorporated herein by reference. A third alternative container 40f11 is shown in FIG. 9C 36 wherein the container is of the collapsible bellows type 1 having a series of pleated folds 244 to allow the container 2 4000' to collapse toward the inlet spout 108. For a more 3 detailed description of the container 40 illustrated in

4 FIG. 9C, see U.S. Patent No. 5,215,222, which has been previously incorporated herein by reference.

6 It should be understood that the term "collapsible 7 container" as used herein is intended to refer to a containers wherein the available volume for viscous 9 material storage is reduced as viscous material is dispensed from the container. As such, the term 11 "collapsible container" shall have its broadest possible 12 meaning and includes containers which have deformable 13 sidewalls or axially movable pistons or ends walls, as 14 disc16sed in the above-noted patents, and any equivalent containers which deform, are reconfigured, or change shape 16 to alter the internal volume available for storage of 17 viscous material as viscous material is dispensed 18 therefrom.

19 When viscous material will not be dispensed for a period of time, such as at the end of the working day, it 21 is desirable to remove the delivery means 84 from the 22 dispensing pump 82. The delivery means 84 is removed or 23 unattached from the dispensing pump by rotating the 24 discharge cylinder 88 clockwise to align the mounting tabs 98 of the male connection or outlet spout 94 with the 26 notched openings 184 in the outer retaining wall 178 of the 27 inlet or female mounting portion 102, and pulling the 28 discharge cylinder 88 away from the dispensing pump 82.

29 Thereafter, a valved or vented cap (not shown) can be placed on the male connection or outlet spout 94. The cap 31 can be a plug which is inserted into the outlet spout 94 32 and which will allow viscous material to flow therethrough 33 if the pump is unintentionally or accidentally operated 34 without the dispensing means 84. The provision of a valved or vented cap would prevent damage to the dispensing pump 36 means due to an overload or overpressure being developed 1 within the conduit member 86. Since there are several 2 structures for providing this function known in the art, 3 and since the cap does not form a part of the present 4 invention, no specific structure for the cap has been illustrated in the present application.

6 Once the cap is installed on the outlet spout 94, the 7 viscous material within the conduit member 86 is isolated 8 from atmosphere and foreign material is prevented from 9 being introduced into the conduit member 86 via the outlet spout 94. If desired, the container 40 and dispensing pump 11 82 can be removed from the cabinet 10 and placed in storage 12 until further dispensing is desired. otherwise, the 13 container 40 and dispensing pump 82 can remain within the 14 dispensing cabinet 10 until the next time dispensing is desired, at which point a clean delivery means 84 can be 16 reattached to the conduit member 86 via the connector means 17 89, as described earlier. By providing a removable 18 delivery means 84, only the portion of the viscous material 19 which is contained within the delivery means 84 must be discarded at the end of the working day, the viscous 21 material within the conduit member 86 being retained for 22 dispensing at a later time. Moreover, only the delivery 23 means 84 must be disassembled for cleaning at the end of 24 the working day. This represents an improvement in the art wherein a greater volume of viscous material must be 26 discarded or wasted when the dispenser is not to be 27 operated for a period of time and wherein the entire pump 28 must be disass emb led and cleaned at the end of each working 29 day.

It should be further understood that the electric 31 motor 52 described herein to drive the dispensing pump 32 means 56 can be replaced by an type of power-operated means 33 (i.e., non-manual), such as hydraulic or pneumatic drive 34 means, and the like. Therefore, the term "motor driven" used in the claims appended hereto shall be given its 36 broadest possible scope, and shall not be limited to the 1 electric motor described hereinbefore. Furthermore, the 2 inventors contemplate that the dispensing pump means could 3 be non-motor driven. i.e., that it could be adapted for 4 manual operation.

While the preferred embodiment of the present 6 invention is shown and described herein, it is to be 7 understood that the same is not so limited but shall cover a and include any and all modifications thereof which fall 9 within the purview of the invention. For example, while preferred, the dispensing cabinet 10 need not include a 11 tampering cabinet. Also, although an automatic poppet-type 12 valve is disclosed as part of the delivery means of the 13 present invention, it is clear that other types of manual 14 or automatic valves could be employed without departing from the scope and spirit of the invention as defined by 16 the claims appended hereto. Moreover, several equivalent 17 types of containers can be used with the dispensing pump is means 56 of the present invention. Likewise, the sealing 19 0-rings described herein are interchangeable with other suitable sealing means. It is also contemplated that the 21 conduit member 86 and discharge cylinder 88 could be 22 integrally formed as a single unit and that the portable 23 containers described herein could be replaced by a 24 refilla ble viscous material receiving hopper or receptacle or other non-portable container. Therefore, the scope of 26 the present invention is not to be limited to the preferred 27 embodiment illustrated herein, but is rather only defined 28 by the claims appended hereto.

Claims

CLAIMS:

1. A motor driven pump comprising:

an inlet means for said material; an outlet means for said material; and reciprocating pump means connected between said inlet means and said outlet means to establish fluid communication therebetween, said pump means having a pump member linearly movable in two directions, said pump member, when moving in one of said linear directions, pressurizing said viscous material to move it toward said outlet means while simultaneously suctioning said material is from said inlet means, said pump member being movable in the other of said linear directions without causing substantial movement of said viscous material toward said inlet means or from said outlet means, said pump member having two portions that are movable relative to each other, said portions moving toward each other when moving in said one linear direction, and away from each other when moving in the other linear direction, said portions including shearing means for deforming or cutting through particulate matter located at an interface area between said portions wherein said portions can move freely toward each other without interference from said particulate matter.

-29

2. A pump according to claim 1, wherein said pump includes a conduit member which defines said inlet and outlet means and said pump member is a piston including inner and outer piston members, said outer piston member being in sliding and sealing engagement with the conduit member and said piston members being movable relative to each other between an engaged and sealed position and a spaced apart and unsealed position.

3. A pump according to claim 2, wherein said shearing means comprises said inner and outer piston members, said inner and outer piston members providing mating surfaces which slidingly and sealingly engage, said mating surfaces producing a shearing action when moved relative to one another to prevent particulate material from remaining between the inner and outer piston members at said mating surfaces.

4. A pump according to claim 3, wherein when said pump member is moved in the other linear direction said viscous material flows around the inner piston member and through the outer piston member.