Abstract:
An automatic dispensing machine provides a portioning chamber, which is separate from the main dispensing chamber. In a preferred embodiment, it also provides a pneumatically-actuated suction to pull the main dispensing valve down to remove used product bags and insert new bags, and it provides an automatically-controlled lift platform to lift up new product to be Inserted into the cylinder. It also provides a dispensing valve design, which provides clean cut-off of product to minimize dripping.

Description:
[0001]     This application claims priority from U.S. Provisional Applications Ser. No. 60/131,312, filed Apr. 27, 1999 and Ser. No. 60/175,952, filed Jan. 13, 2000. Ice cream dispensing machines are known, in which the ice cream or other product is placed in a cylinder, and a plunger moves along the cylinder, pushing the product out a spout. A known machine is shown in U.S. Pat. No. 5,421,484 “Beach”, which is hereby incorporated by reference. These machines are operated by a person pulling a lever. While the lever is being pulled, it causes a valve to open to provide air pressure, which causes the plunger to move in the cylinder, dispensing the ice cream. Pulling the lever also opens a dispensing valve, so the product which is being pushed by the plunger can leave the machine through the dispensing valve. Usually, the machine has more than one cylinder, each cylinder having its own control lever, and each cylinder being independently operated. 
     
    
     BACKGROUND OF THE INVENTION  
       [0002]     The problem with these prior art machines is that they provide no portion control. The amount of product that is dispensed depends on the individual operator. One operator may dispense large servings, and another operator may dispense small servings, so there is no consistency in the serving size. This also means that the price being charged for the serving may be too much or too little, depending upon the size of the serving that is dispensed. Also, this arrangement is not suitable for automatic dispensing from a coin-operated dispenser.  
         [0003]     The problem of coming up with an economical, reliable, automatic dispensing machine has been considered for several years by various companies, but nobody has yet designed a practical solution. The portions cannot be measured accurately by weighing the cone or cup into which the product is dispensed, because part of the portion being dispensed is still suspended form the dispenser. The portions cannot be measured by measuring flow rate, because the viscosity of the fluid changes dramatically with slight changes in ambient conditions or slight changes in temperature or recipe. It is difficult to measure accurately by measuring the distance dispenser plunger represents a large volume.  
       SUMMARY OF THE INVENTION  
       [0004]     The purpose of the present invention is to provide simple, accurate, economical, reliable, easily cleaned, automatic portion control for dispensing machines.  
         [0005]     The present invention accurately measures the volume of product that is dispensed. Rather than measuring the distance traveled by the main, large plunger, a second smaller-diameter portioning plunger is provided, which can be more accurately controlled. The portioning plunger may have only a single stop for dispensing only a single portion size at a time, or multiple stops may be provided to permit different portion sizes.  
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0006]      FIG. 1  is a front view of a dispensing machine made in accordance with the present invention;  
         [0007]      FIG. 2  is a front sectional view of the machine of  FIG. 1 ;  
         [0008]      FIG. 3  is a side view of the machine of  FIG. 1 ;  
         [0009]      FIG. 4  is a side sectional view partially broken away form the machine of  FIG. 1 ;  
         [0010]      FIG. 5  is a schematic side view showing a first step in the dispensing process of the machine of  FIG. 1 ;  
         [0011]      FIG. 6  is the same as  FIG. 5  but showing the next step of the process;  
         [0012]      FIG. 7  is the same as  FIG. 6  but showing the next step of the process;  
         [0013]      FIG. 8  is the same as  FIG. 7  but showing the next step of the process;  
         [0014]      FIG. 9  is the same as  FIG. 8  but showing the next step of the process;  
         [0015]      FIG. 10  is the same as  FIG. 9  but showing the next step of the process;  
         [0016]      FIG. 11  is a perspective view of parts of the dispenser of  FIG. 1 , including the main product cylinder, the portioning cylinder, and the dispensing cylinder as well as the actuators which control the movement of plungers in those cylinders;  
         [0017]      FIG. 12  is a perspective view of the inside of the door of  FIG. 1  partially as well as the actuators which control the movement of plungers in those cylinders;  
         [0018]      FIG. 12  is a perspective view of the inside of the door of  FIG. 1  partially broken away;  
         [0019]      FIG. 13  is a perspective view of the upper cover half for the main product cylinder, the portioning cylinder, plunger, and actuator, and the dispensing cylinder, plunger and actuator of  FIG. 1 ;  
         [0020]      FIG. 13A  is a side sectional view through the cover, portioning cylinder, and dispensing cylinder of  FIG. 13 ;  
         [0021]      FIG. 13B  is a top view of the cover of  FIG. 13 ;  
         [0022]      FIG. 13C  is a side view of the portioning cylinder of  FIG. 13 ;  
         [0023]      FIG. 14  is a schematic side view of the dispenser of  FIG. 1 ;  
         [0024]      FIG. 15  is the same view as  FIG. 14  but showing the storage platform partially pivoted forward;  
         [0025]      FIG. 16  is the same view as  FIG. 15  but showing the storage platform fully pivoted forward for loading spare product;  
         [0026]      FIG. 17  is a side view of the storage platform of  FIG. 14 ;  
         [0027]      FIG. 18  is a front view of the storage platform of  FIG. 14 ;  
         [0028]      FIG. 19  is a side view of the tube which provides the fluid path from the main product cylinder to the product outlet of the machine of  FIG. 1 ;  
         [0029]      FIG. 20  is a top view of the tube of  FIG. 19 ;  
         [0030]      FIG. 21  is a bottom view of the tube of  FIG. 20 ;  
         [0031]      FIG. 22  is a side view of an alternative tube to provide the fluid path from the main product cylinder to the product outlet without the use of a portioning cylinder;  
         [0032]      FIG. 23  is a top view of the tube of  FIG. 22 ;  
         [0033]      FIG. 24  is a bottom view of the tube of  FIG. 22 ;  
         [0034]      FIG. 25  is a sectional view of the dispensing tube of  FIGS. 19 and 22 ;  
         [0035]      FIG. 26  is an enlarged view of the bottom portion of the dispensing tube of  FIG. 25 ;  
         [0036]      FIG. 27  is a sectional view through the dispensing tube, portioning and dispensing cylinder of the machine of  FIG. 1 ;  
         [0037]      FIG. 28  is a schematic of the portion of the pneumatic control system for the machine of  FIG. 1  which controls the portioning and dispensing actuators;  
         [0038]      FIG. 29  is a schematic of the portion of the pneumatic control system of the machine of  FIG. 1  which controls the main product cylinders; and  
         [0039]      FIG. 30  is a schematic for an alternate electrical control system to control the machine of  FIG. 1 .  
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0040]      FIGS. 1-4  are schematic views of an example of a dispending machine  10  made in accordance with the present invention. THE machine  10  includes a refrigerated storage chamber  12  and a door  14  which pivots relative to the housing of the refrigerated storage chamber  12  so that, in a first position, the door  14  closes the storage chamber  12 , and, in a second position, the door  14  provided access into the storage chamber  12 .  
         [0041]     This particular machine  10  dispenses four cylinders of product at any given time. Obviously, the number of cylinders form which the dispenser is designed can be varied, depending on the customer&#39;s needs. The four main product cylinders  16  stand adjacent to each other in the front of the refrigerated tempering and storage chamber  12 . Extra product  18  is stored on a storage platform  20  behind the main product cylinders  16 . The storage platform  20  rests on the bottom of the storage chamber  12  and is mounted to the sidewalls of the refrigerated chamber  12  at left and right pivot points  22 . There is a bar  23  extending along the platform  20  in from of the extra product bags  18 , and there are left and right linkage plates  25 , pivotably connected to the platform bar  23  and to a main product cylinder bar  27 .  
         [0042]     On the inside surface of the door  14  is a spring-biased button  24 , which is depressed when the door closes and which projects outwardly when the door opens. This serves as a sensor. On the side of the door  14  is another button or a key lock  26 , which is manually shifted in position in order to signal the control system to unlock the door  14 . There are holes  28  through the door, which permit product-dispensing tubes  30  to extend through from the inside of the door to the outside of the door. Inside the door  14  are dispenser actuators  32  and portioning actuators  34 . On the front surface of the door  14  are lights or other “ready” indicators  36 , small portion buttons  38 , and large portion buttons  40 . Also on the front of the machine  10 , below the door  14 , are foot actuator pedals or buttons  42 .  
         [0043]      FIGS. 5-10  show schematically the main operating components of the dispenser  10  and the normal sequence for dispensing product. A spare bag  18  of product  44  is placed inside a main product cylinder  16 . A dispensing path  46  is provided between the main product cylinder and the product outlet  48  by the tube  30 . Along the dispensing path  46  are a portioning cylinder or chamber  50  and a dispensing cylinder or chamber  52 , which will be described in more detail later. There is a main piston  54  in the main product cylinder  16 , which pushes product  44  out of the main cylinder  16  to dispense the product  44  from the machine  10 . There is a portioning plunger  56  in the portioning cylinder  50 , and there is a dispensing plunger  58  in the dispensing cylinder  52 . There is a portioning plunger actuator cylinder  60 , and there is a dispensing plunger actuator cylinder  62 , which actuate their respective plungers  56 ,  58 . The main dispensing cylinder  16  has a flexible cylindrical bag of product  44  inside. It should be noted that the portioning cylinder  50  has a much smaller diameter of approximately six to ten inches, the portioning chamber  50  may have a diameter of approximately two inches.  
         [0044]      FIG. 5  shows the normal starting point. In order to dispense one portion, the operator checks to be sure that the “ready” indicator  36  for that particular dispenser is on, indicating that the dispenser is ready to dispense product, and then the operator depresses a dispensing button  38  or  40 , selecting the portion size to be dispensed. This causes the piston  56  to be extended to dispense a portion of product.  FIG. 6  shows the dispensing plunger  58  retracting.  FIG. 7  shows the portioning plunger  56  extending to push product  44  out the outlet  48 . Once the product has been dispensed, the dispensing plunger  58  is extended to close off the outlet  48 , and the main piston  54  is pushed upwardly to refill the portioning chamber  50 , as shown in  FIG. 8 . This returns the machine to the initial position, as shown in  FIG. 9 , where the process can be repeated, as shown in  FIG. 10 .  
         [0045]      FIGS. 11-13C ,  19 - 21 , and  25 - 27  show the fluid pathway and the main moving parts in more detail. The cylinder  16  has a bag  18  of product  44  inside and has a plunger or piston  54 , which seals against the internal wall of the cylinder  16 . A fluid, preferably air, is received below the piston  54  through a port  64  in order to push the piston upwardly. In order to retract the piston  54 , a vacuum is pulled though the port  64 , as will be described later. Fixed to the tope of the cylinder  16  is a lower cover half  66 . An upper cover half  68  is hinged to the lower cover half  66  about the pivot axis  70 , which is the axis of the tube  27 , which extends through all the cover halves  66 ,  68 . The upper and lower cover halves  69 ,  66  surround and support the dispending tube  30 , which has one end inside the bag  18  of product  44  and the other end forming the outlet  48 . A portioning cylinder  50  fits into the sleeve and is locked into position with a twisting motion, as will be described later. When the upper and lower cover halves  68 ,  66  are clamped together, as is well known in the art, the bottom surface of the portioning cylinder  50  abuts and seals against an O-ring seal  73  on an upwardly-projecting sealing surface of an upwardly-directed opening  67  in the tube  30 . Flanges  69  on the outer surface of the tube  30  keep the tube centered in its proper position with respect to the cover. The tube  30  projects inside of the spout (not shown) on the bag  18  and seals against the bag&#39;s spout, thereby providing a sealed pathway from the inside of the bag  18  through the tube  30  to the outlet  48 , as is well known in the art. (The portioning cylinder sleeve  47  and portioning cylinder  50  are not part of the typical tube  30  known in the art.)  
         [0046]     The inner surface of the portioning sleeve  47  is tapered inwardly at the bottom and defines four vertical grooves  53 . The portioning cylinder or chamber  50  has a corresponding taper near the bottom, and terminated at its bottom edge with wings  55 , which, for installation, slide down the vertical grooves  53  to a point below the grooves  53 . The portioning cylinder  50  is then twisted, thereby locking the portioning cylinder  50  in position on the upper cover half  68  as shown in  FIG. 13A . The portioning cylinder  50  is made as a separate, removable piece for ease in cleaning. The top outer edge of the portioning cylinder  50  defines threads  57 , and a cap  65  is threaded onto the top edge of the cylinder  50  to prevent the portioning plunger  56  from accidentally lifting completely out of the portioning cylinder  50 . The cap  65  projects inwardly only far enough to stop the plunger  56 , but is otherwise open, in order to permit the portioning actuator  60  to act on the plunger  56  from above. The portioning plunger  56  fits down into the portioning cylinder  50  and seal against the inner surface of the portioning cylinder  50  by means of O-ring seals. It can be seen in  FIGS. 11, 13 , and  13 A that the portioning plunger  56  has a simple cylindrical shape with flat top and bottom surfaces  71 .  
         [0047]     The dispensing plunger  58  is also cylindrical in shape, but it has a groove  58 A in its outer surface, which defines a circular flange  58 B. It also has grooves which receive O-ring seals, and it has a tapered outer surface near the bottom and a concave bottom surface, which will be described below. This shape of the dispensing plunger  58  is preferred, because it does not Interfere with closing the upper cover half  68  with the plunger  58  in place, and because it does not require the plunger  58  to have any particular orientation in order to connect to its actuator when the door closes. It should be noted that, during operation of the dispensing machine  10 , the locations of the portioning chamber  50  and dispensing chamber  52  remain fixed relative to the cylinder  16 , and the plungers  56 ,  58  remain in their respective chambers  50 ,  52 , so when the door opens and closes, the plungers  56 ,  58  must separate from and then rejoin their respective actuators  32 ,  34  as indicated by the arrows in  FIG. 11 .  
         [0048]     The bottom of the dispensing cylinder  52  and its respective dispensing plunger  58  have a special shape which helps prevent product from sticking to the dispenser and dripping after the dispensing cylinder is closed. The dispensing cylinder or housing  52  is cylindrically-shaped, but, at the outlet  48 , there are inwardly and downwardly projecting, pointed leaves  49  extending from the cylindrical side wall of the cylinder  52 . The dispenser plunger  58 , at its lower edge, defines an inwardly and downwardly tapered surface  59 , which intersects at circle  61  with a central concave surface  63 . The circle  61  contacts the points of the leaves  49  when the plunger  58  is down, and the tapered surface  59  of the plunger  58  lays at the same angle as the leaves  61  and firmly contacts the inner surface of the leaves  49 . The firm contact between the tapered surface and the leaves, the spacing between the leaves, and the intersection of the circle  61  with the points of the leaves provides little opportunity for product to adhere to the dispenser outlet  48 . This greatly reduces any dripping problem.  
         [0049]     The actuators  32 ,  34  preferably are fluid-operated cylinders  60 ,  2  as shown in these figures, although electrically-operated actuators could also be used. A portioning piston rod  60 A projects from the portioning actuator cylinder  62 . At the bottom of the portioning piston rod  60 A is a flat disk  60 B. At the bottom of the dispensing actuator  62 A is a flat receptacle  62 B, having a C-shaped cross section. The C-shaped receptacle  62 B receives and hooks around the flange  58 B of the dispensing plunger  58  so it can raise and lower the dispensing plunger  58  as the dispensing piston rod  62 A travels up and down. The dispensing cylinder  62  preferably is spring-biased downwardly.  
         [0050]     As part of the control system, switches  72  are mounted inside the door  14 . The number of switches  72  is selected depending upon the number of different portion sizes to be dispensed by the dispenser.  FIG. 13  shows three switches  72  for a dispenser that dispenses two portion sizes, and  FIG. 12  shows two switches for a dispenser that dispenses a single portion size. A contactor rod  74  is mounted to move up and down with the portion actuator rod  60 A, and the contactor rod  74  includes a contactor  76 , which is fixed on the contactor rod  74  and contacts the switches  72  as it travels up and down. This controls the portion size, as will be explained later. A locking latch  78  is provided on the inside of the door  14  and is rotated by the control system which is actuated by the key or bottom  26  on the side of the door. The locking latch is received in a slot (not shown) on the wall of the refrigerated chamber  12  to lock the door.  
         [0051]      FIGS. 14-18  show a lift and tilt system, which helps shift stored bags  18  of product upwardly and forwardly to make it easier for the operator to reach them when it is time to re-load a main product cylinder. The extra containers  18  of product  44  are stored within the tempering-refrigeration chamber  12  behind the dispensing cylinders  16  on the platform  20 . The platform  20  is raised and lowered by a lift cylinder  80 , which is actuated by a manually-operated switch. Then the cylinder  80  is pressurized, it causes the platform  20  to shift upwardly and forwardly, pivoting about the pivot points  22 . This also pivots the main cylinders  16  forward, making the extra containers  18  readily accessible. Once an extra container  18  has been removed form the tempering-refrigerated chamber and set aside, and perhaps another container  18  has been placed onto the platform  20  for tempering, the operator actuates a switch to retract the cylinder  80 , returning the platform to its initial position. This lift and tilt system can only be activated when the service door  14  is open.  
         [0052]     The normal sequence for reloading the product cylinders  16  is as follows:  
         [0053]     First, the door  14  is opened. Then the operator activates a switch, which causes the platform  20  to pivot forward. Then the operator removes a stored bag  18  from the platform, sets it aside, activates a switch to return the platform  20  to its original position, and closes the door  14 . Then, the operator puts a clean tube  30  on the new bag  18 , pressing the tube  30  against the opening in the bag to seal the tube to the bag. Then, the operator opens the door  14 , opens the upper cover  68  for the main product cylinder  16  to be refilled, hits the foot pedal for that cylinder to pull the main plunger  54  down a bit, and removes the used product bag. Then the operator takes the newly prepared bag  18  with tube  30  installed, set it on the plunger  54 , and presses and holds the foot switch to retract eh plunger  54 , guiding the bag  18  as it travels downwardly with the plunger  54 . Then the operator closes the upper cover  68  and clamps the upper and lower cover halves together. Then the operator closes the door  14  and the machine is ready to dispense the new product.  
         [0054]     The only parts of the dispenser that contact product are the bag  18 , the tube  30 , the portioning chamber  50  and portioning plunger  56 , and the dispensing chamber  52  and dispensing plunger  58 . The bag  18  generally is thrown away when it is empty, although I could be recycled. The other contact parts can readily be removed and replaced with clean parts, and the used parts can be brought to a sink or washbasin and cleaned for re-use later.  
         [0055]      FIGS. 22-24  show an alternative embodiment of a tube  30 A, which could replace the tube  30  if portion control is not desired. If this tube  30 A were used, the operator would simply press the dispensing button for the desired time period to dispense product.  
         [0056]     The schematic of the control system for the machine of  FIG. 1  is shown in  FIG. 28 . In this preferred embodiment, the control system is pneumatic and includes a pneumatic circuit board. While the schematic shown in  FIG. 28  is for a single product cylinder dispenser, it is understood that the dispensing machine is intended to have a plurality of dispensers, so some parts of the system will be repeated multiple times in one machine. For example, in the preferred embodiment, there are four dispensing cylinders  16  in the machine and four corresponding small portion and large portion buttons and actuators for the four cylinders.  
         [0057]     The dispenser actuator cylinder  62  and the portioning actuator cylinder  60  are shown on the right side of the schematic. There is a compressor (not shown), which provides pressurized air to run the system. The pressurized supply sir enters the system at the point  82  and enters through the door switch valve  84 , which is activated by the door open button  26 , when the door is open.  FIG. 28  shows the position of the door switch valve  84  when the door is closed. The machine will only dispense product when the door  14  is closed. Supply air is also provided to various valves at points indicted by the letter “S”.  
         [0058]     When the service door  14  is open, the door switch  84  causes the dispenser actuator valve  86  to send supply air to the top of the dispenser actuator cylinder  62 , which extends the dispensing plunger  58  to close off the outlet  48 . When the door is open, it also causes supply air to be sent to the bottom of the portion actuator control cylinder  60 , retracting the portioning control cylinder  60 . It also prevents a pilot signal from the portion control form passing to pilot the ice cream cylinder valve  88 , shown in  FIG. 29 , which prevents the man piston  54  from pushing product out of the main cylinder  16 . It also permits the manual valve  90  to be activated by the operator, to cause the platform lifting cylinder  80  to be extended, lifting the product support platform  20  and to be retracted, returning the support platform  20  to its starting position.  
         [0059]     When the service door is closed, the door switch  84  moves to its second position, shown in  FIG. 28 . In this position, supply air is connected to the large and small portion start buttons  38 ,  40  and to the first sequencing control valve  92 .  
         [0060]     To dispense a large portion of product, the operator first pushes the large product start buttons  38 , which permits supply air to pass through the large portion start valve  38  to the small/large pilot control valve  93 , shifting that valve to the left, so that the dispensing will not stop until the portioning actuator  60  sees contact with the lowermost portioning switch  72 C. The air passing through the large portion valve  38  also passes through a shuttle valve to the pilot valve  94 . Unless the main piston  54  is being pushed, which would close off the pilot valve  94 , the valve  94  will then provide pressure to the top of the valve  86 , moving it to its second position, which permits supply air to enter the bottom of the dispensing plunger  58 . It also sends supply air to the top of the portioning actuator cylinder  60 , which moves the portioning plunger  56  down. The portioning plunger  56  will continue to move downwardly, dispensing the product, until the lowermost switch  72 C is contacted by the contactor  76 , at which point supply air will pass through the switch  72 C, through a shuttle valve, and will pilot the first sequence control valve  92  to the left, causing supply air to pass through the first sequence control valve  92  to cause compressed air to raise the main piston  54 , and causing the pilot valve  94  o shift to the right and the small/large pilot valve to shift to the left. The air going through the lowermost switch  72 C will also cause the dispensing actuator  62  to shift downwardly, closing the outlet, and relieves pressure from the portioning cylinder  60 , so that the product being pushed up by the main piston  54  will fill the portioning chamber  50 , causing the portion actuating cylinder  60  to move upwardly until the uppermost switch  72 A is tripped by the contactor  76 .  
         [0061]     It also causes the sequencing valve  92  to shift to the right, relieving air pressure from the main dispensing cylinder  16 , and readying the system for the next time an operator presses a button  38  or  40 . When the upper position switch  72 A is switched, it gives a signal to the “Ready Indicator”  36 , telling the operator that the machine is ready again to dispense product.  
         [0062]     To dispense a small portion, the operator presses the small portion button  40 , which allows air to pass through the door switch valve  84 , through the small portion switching valve  40 , to the left side of the small/large pilot valve  93  shifted to the right, supply air passes through the small/large pilot valve  93  to the middle switch  72 B, so that, when the middle switch  72 B is tripped, the first sequence control valve is shifted to the left, the dispensing actuator is shifted downwardly, pressure is relieved form the portioning actuator cylinder  60 , and the main cylinder  16  is pressurized pushing the product up, out of the main cylinder  16  in order to refill the portioning chamber for next time. While this schematic does not show a payment receiving control (such as a coin or bill or credit card receiver) which must be activated before the valves  38 ,  40  can be activated, it will be obvious that such a modification may be made in order to make this machine completely self-vending, so that it could be placed in a public location for direct access by customers.  
         [0063]     The portion of the control system providing compressed air or vacuum to the bottom of the main dispensing cylinder is shown in  FIG. 29 . The pilot signal  87  coming from the lower left side of the schematic on  FIG. 28  enters its respective point in  FIG. 29 . When a pilot signal is received into the cylinder  16  to push product up, out of the cylinder  16 . Alternatively, if the door  14  is open and one of the foot switched  42  is depressed, air will pass through the door switch valve  84  through the foot switch  42 , to the shuttle valve for the respective cylinder  16 , again opening a path onto the cylinder  16 . However, in this case, the pressurized air supply S coming form the compressor will be passed through a Venturi circuit, drawing a vacuum on the bottom of the respective cylinder  16  and pulling the piston  54  down. If there is no pilot signal  87  and the door is closed (or the door is open and the foot switch  42  has not been depressed), then the main cylinder control valve  88  vents the bottom of the main cylinder  16  to atmosphere. It is very advantageous that the controls for this system are fluid-operated, as this avoids the problem of having electrical coils for an electrical control system in the area, where they would tend to heat the product.  
         [0064]      FIG. 30  shows an alternative control system, in which electrical controls are used instead of the pneumatic controls described above. In this case, there would be a central processor  100 , which would receive inputs from the various operator-actuated controls and the sensors and which would then transmit signals to the appropriate actuators (usually solenoid valves) to open and close the valves to operate the machine as described earlier.  
         [0065]     It will be obvious to those skilled in the art that modifications may be made to the embodiments described above without departing from the scope of the present invention.