Patent Publication Number: US-2011068120-A1

Title: Dispensing Apparatus and Method for Semi-Solid Product

Description:
CROSS-REFERENCES TO RELATED APPLICATIONS 
     This application is a continuation of U.S. patent application Ser. No. 12/683,116, filed Jan. 6, 2010, pending; which is a continuation of U.S. patent application Ser. No. 10/479,894, filed Apr. 14, 2005, now U.S. Pat. No. 7,665,630; which is the U.S. national phase of International Application No. PCT/GB02/02772 filed Jun. 17, 2002 which designated the U.S. and claims priority to Great Britain Patent Application No. 0114685.1 filed Jun. 15, 2001, the entire contents of each of which are hereby incorporated by reference. 
    
    
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
     (NOT APPLICABLE) 
     BACKGROUND OF THE INVENTION 
     This invention relates to a method and apparatus for dispensing products from containers, in particular the dispensing of products by extrusion, the product having a consistency suited to extrusion. 
     It has been proposed to dispense food products, such as ice cream, from containers by extrusion and several kinds of containers have been proposed for this purpose including a large multi-portion container and containers which are suited to dispensing a single portion of product. 
     In dispensing product from multi-portion containers, problems have arisen in arranging for portions to be dispensed without manual intervention, that is the delivery of portions has usually had to be achieved by manual operation of a valve. 
     BRIEF SUMMARY OF THE INVENTION 
     An object of the invention is to provide a dispensing system and method in which the dispensing of portions may be more easily controlled and, if necessary, without manual operation of the outlet valve. 
     According to one aspect, the invention provides a method of dispensing semi-solid product by extrusion wherein a container of product is pressurised to cause the product to be discharged by extrusion through an outlet from the container into a flexible tube, controlling the flow of product from the outlet through the tube to an outlet nozzle and drive means for causing the flexible tube to be compressed to express product from the tube towards the nozzle. 
     Preferably the flow of product is controlled by a first inlet valve between the container outlet and the flexible tube and a second outlet valve between the flexible tube and the nozzle. 
     The first valve may be opened to admit product into the tube with the second valve closed, the first valve may then be closed and the second valve opened, and then the drive means may then be operated to compress the tube and express product in the tube through said nozzle which is located downstream of the second valve. 
     Conveniently, operation of the drive means is controlled to express a predetermined portion of the product in the tube through the nozzle, the size of the portion ranging between all said product in the tube and a proportion of said product. 
     The drive means may include tube engagement means which is moveable reciprocally towards and away from tube to compress the tube. 
     Preferably the first and second valves are spaced apart along the tube to open and close the tube by reciprocal movement to engage, deform and close the tube at said spaced positions. 
     The container outlet may be releasably connected to the tube, which tube extends downwards towards the outlet nozzle which is shaped to shape product discharged therethrough and which may be releasably attached to the tube. 
     In one arrangement the drive means include tube engagement means moveable along the tube towards the outlet nozzle to discharge the tube contents. 
     The tube engagement means may include a roller which engages the tube at one end thereof and moves towards the outlet nozzle after said engagement. 
     The flow of product from the container may be controlled by an outlet valve between the tube and the nozzle, and by the drive means. Preferably the container and flexible tube are contained within a refrigerated environment, the nozzle projecting outwards from said environment. 
     According to another feature of the invention there is provided apparatus for dispensing semi-solid product, comprising a container of product, the container having an outlet, pressurising means for putting product in the container under pressure to thereby extrude product from the outlet, flexible tube means communicating with the outlet at one end and with an outlet nozzle at the other end, drive means for engaging the flexible tube to deform the tube and cause product in the tube to be discharged through said nozzle, and valve means for controlling the flow of product from the nozzle. 
     Preferably, the valve means includes a valve adjacent the nozzle, which valve controls the flow of product from the tube to the nozzle. 
     The valve means may include a further valve between the container outlet and the tube to control flow of product to the tube. 
     The drive means conveniently includes a reciprocal drive member arranged to engage the flexible tube to deform and flatten the tube whereby to cause product in the tube to be discharged from said nozzle. 
     In one arrangement the reciprocal member is moveable along the tube towards said nozzle after engaging the tube. 
     The container outlet and the flexible tube may be releasably connected to one another, and the tube is removable from the apparatus for replacement and/or sanitising. 
     Preferably the container and the flexible tube are located in a refrigerated housing whereby to keep product frozen, the nozzle projecting outwardly from the housing. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Further features of the invention will appear from the following description of an embodiment of the invention given by way of example only and with reference to the drawings, in which: 
         FIG. 1  is a vertical, schematic section through one embodiment of dispensing apparatus, 
         FIG. 2  is a vertical section of part of the apparatus of  FIG. 1  at one stage of operation, 
         FIG. 3  is a view corresponding to  FIG. 2  in another stage of operation, 
         FIG. 4  is a view corresponding to  FIG. 2  in another stage of operation, 
         FIG. 4A  is a vertical section of that part of the apparatus of  FIGS. 2-4  with a modified drive, 
         FIG. 5  is a partial vertical section of an alternative arrangement of that shown in  FIGS. 1-4 , 
         FIG. 6  is an alternative drive arrangement to that shown in  FIG. 5 , 
         FIG. 7  is a view corresponding to  FIG. 6  showing one stage of operation, 
         FIG. 8  is a view corresponding to  FIG. 7  in another stage of operation, 
         FIG. 9  is a view corresponding to  FIGS. 7 and 8  in another stage of operation, 
         FIG. 10  is a view corresponding to  FIGS. 6-9  in another stage of operation, 
         FIG. 11  is a schematic vertical section through alternative apparatus to that of  FIG. 1  employing a different container, 
         FIG. 12  is a view of the apparatus of  FIG. 11  showing recharging of a container, 
         FIG. 13A  and  FIG. 13B  are embodiments of container suitable for use in the  FIG. 1  apparatus. 
         FIG. 14A  is a vertical section through apparatus similar to that of  FIG. 1  employing the container of  FIG. 13B , 
         FIG. 14B  is a side elevation of the apparatus in  FIG. 14A , 
         FIG. 15  is a side elevation of apparatus similar to that of  FIG. 1  employing two containers, 
         FIG. 16  is an elevation showing an alternative drive system for dispensing from containers, 
         FIG. 17  is a vertical section of apparatus similar to that of  FIG. 1  showing container removal arrangement, 
         FIG. 18  is a view corresponding to  FIG. 17  showing another container removal arrangement, 
         FIG. 19A  and  FIG. 19B  show container discharge means for the apparatus of  FIG. 1  in alternative positions, 
         FIGS. 20A ,  20 B and  20 C show a container drive arrangement with overload protection in three different positions, 
         FIGS. 21A ,  21 B and  21 C show part of another container drive system with overload protection, and 
         FIG. 22  shows in vertical section apparatus similar to that of  FIG. 1  with drive overload protection. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring to the drawings and firstly to  FIGS. 1-4 , there is shown apparatus for dispensing semi-solid or viscous ice cream product. The apparatus includes a housing  10  which has refrigeration means  11  whereby the interior of the housing  10  is kept at a suitable temperature, usually below freezing point, but sometimes above, suited to the food products (usually ice cream product) to be dispensed. The housing  10  is arranged to have storage capacity for filled ice-cream containers  12  to be dispensed. A container  12  ready to be dispensed is located on a seating  13  mounted within the housing  10 . 
     The container  12  is formed with a base portion  14  and a closure  15  which has an upwardly directed deformable portion which, during dispensing of product from within the container, is deformed by being inverted until it adopts the contours of the inner surface of the base  14  by which time the container contents are fully discharged. In this case, the outlet on the container is formed with a nozzle  39  which tapers inwardly away from the container  12 . The closure  15  is usually located over the base  14  when the base has been filled with product to thereby seal the container, the closure  15  fitting over the upper edges of the base  14 . 
     The base  14  and closure  15  are preferably heat-sealed to one another when filled. In some cases the container  12  is formed as a sealed assembly before product is introduced into the container in which case the container is filled through the nozzle  39 . Heat sealing prevents re-use of the container. 
     The container  12  is located on the seating  14  which has an opening in its base through which the nozzle  39  is directed. There is also provided an abutment plate  18  to resist the pressure exerted on the container during dispensing. Dispensing is caused by a drive arrangement  20  which consists of a plunger  21  mounted on a rod  22  and driven by a linear drive arrangement  23 , the linear drive arrangement usually taking the form of an electric motor, rotation of which is converted into a linear reciprocating movement of the plunger  21 . The drive arrangement is mounted on the housing pivotable about a pivot axis  24 . 
     The plunger  21  is arranged to engage the deformable portion of the container  12  whereby to deform that portion downwardly towards the base  14  and thereby discharging, by extrusion, ice cream from the container through the nozzle  39 , which has a smaller cross-section than the container. 
     The nozzle  39  is releasably, sealingly connected to a flexible tube  25  which extends downward from the outlet nozzle  39  and the tube  25  is integral with or connected to a discharge nozzle  26  at its opposite end. 
     The tube  25  is sufficiently flexible to be deformed so that it is substantially flat with one inner side wall of the tube engaging the opposite side wall. Alternatively, the tube  25  is deformable so that the tube retains a part circular shape over the portion into which the other portion deforms, the tube being supported by a part circular support. 
     Associated with the flexible tube  25  are upper and lower valves  27  and  28 . The valves  27  and  28  are reciprocally moveable towards and away from the tube  25  whereby to pinch the tube and act to prevent product from passing along the tube beyond the associated valve. For this purpose the head of the valve is formed with a tapered end which extends across the width of the tube  25 , in each case. Alternatively the heads of the valves are shaped according to the shape of the tube support. 
     In addition to the valves  27  and  28  there is provided a reciprocally moveable tube discharge plate  29  comprising a flat plate which is arranged to engage the tube  25  and cause the contents to pass downwardly and out of the nozzle  26  when the valve  28  is open. Alternatively, the plate  29  is formed with a portion engaging the tube which is shaped according to the shape of the tube support, for example, part circular. 
     The valve  28  has drive means  30  to move the valve backwards and forwards between a closed and an open position. Similarly the valve  27  has drive means  31  which causes movement of the valve head towards and away from the tube  25 . As illustrated in  FIG. 1  the drive means  31  also is arranged to move the drive plate  29  but the valve  27  and the drive plate  29  may have separate drive means. The drive means are conveniently linear drives which include an electric motor whose rotary movement is converted into a linear movement, for example through a worm and worm-wheel. 
     There will now be described the sequence by which discharge of containers  12  is achieved with particular reference to  FIGS. 1-4 . 
     In  FIG. 1  the container  12  is put under pressure by engagement by the plunger  21 , the valve  27  is in the open position and the valve  28  is closed. The tube  25  fills with product extruded from a container  12  and pressure is released from the container  12  after a specific lapse of time ( FIG. 1 ) and the plunger  21  may be backed off from the container  12 . 
     The valve  27  is now closed to restrict further passage of product into the tube  25  and valve  28  is opened. When the valve  27  has closed the upper end of the tube  25 , the discharge member  29  begins to engage the tube  25 , as shown in  FIG. 2 , so that product is discharged from the tube  25  through the nozzle  26  into a receptacle for the product (not shown) which may be a cone or dish. Pressure of the member  29  continues to be applied to the tube  25  so that product in the tube  25  can be fully discharged from the nozzle  26  ( FIG. 3 ). If desired, only a predetermined portion of the product in the tube  25  may be discharged, movement of the member  29  being interrupted when the required amount has been discharged and the drive means  31  may be programmed to move a measured predetermined amount or for a predetermined time depending, for example, on a prepayment made to the apparatus in coin-freed mode. Thus, for example, half the amount in the tube  25  may be discharged for half the payment required for discharge from the full tube. 
     More particularly the apparatus may be arranged to dispense any preselected amount of product between complete discharge of the tube and minimum discharge. The user may be able to select the amount dispensed by the use of controls or buttons on the apparatus, for example, for 120 ml, 180 ml or 250 ml, or by the amount of payment made by, for example, coin or note insertion, credit card or the like and one payment may enable several portions of different sizes to be dispensed. The control on the apparatus may include audible information to the user, for example, by electronic voice information. The preselected amounts to be dispensed are transmitted to the dispensing means which moves to dispense the selected amounts. 
     After the required amount has been discharged from the tube  25 , the valve  28  is moved to a closed position, as shown in  FIG. 4 . Thereafter the member  29  and the valve  27  are withdrawn from engagement with the tube  25  so that the tube  25  may be refilled upon application of further pressure to the container  12 . 
     In determining the quantity discharged, account is taken of a small quantity discharged by operation of the valves. 
     It is usually not desirable for product in the container  12  to be pressurised for extended periods when not in use as this can affect the quality of the product in the container. Accordingly, control means may be provided to automatically back off the plunger  21  from the container after a predetermined lapse of time since the apparatus was last operated. Backing off may move the plunger back a small distance from the container. 
     It will be appreciated that the drive  23  for the plunger  21  operates at a fixed speed which permits ready control of dispensing quantities from the container  12  by time and/or distance. 
     As shown in  FIG. 1-4  the member  29  and valve  27  are driven by a common drive  31  but it will be appreciated that a further drive similar to the drive  31  can be employed for operating the valve  27  so that this is operated independently of the member  29 . In the illustrated arrangement, using a common drive  31 , the valve  27  incorporates spring means  33  whereby after the valve  27  has engaged the tube  25  to stop flow from the container  12  the support for the valve  27  is moveable forward with member  29  to compress the tube  25 , the spring  33  compressing to enable the valve  27  to take up said further movement. An abutment plate  35  is provided behind the tube  25  to act as an abutment to the compressive action on the tube  25  by the valves  27 , 28  and member  29 . 
     Product discharging from the nozzle  26  is directed downwardly so that the product descends under gravity into the receptacle and there is provided a drip tray  36  to receive any product falling from the nozzle  26 , there being defined a recess  37  in which the receptacle is held by the operator. 
     The container  12  is formed with a tapering nozzle  39  which defines the outlet from the container  12  and the nozzle is arranged to sealingly engage into the upper end of the tube  25 , the tube  25  being readily releasable from the nozzle  39  for replacement and/or cleaning. The member  29  is conveniently attachable to the side of the tube  25  which it engages. After a dispensing action the member  29  may be moved rearwards drawing the tube with it which acts to draw back into the tube product which is below the member  29  and in the nozzle  26 . 
     In order to readily release the tube  25  and associated nozzle for cleaning or replacement, the abutment plate  35  may be hinged to move it out of the way and access through a door into the housing permits removal of the tube, preferably without the use of tools. The tube  25  may be washable or may be replaced. 
     Referring now to  FIG. 4A  there is shown the arrangement of  FIGS. 1-4  in which the drives  30  and  31  are replaced by a single drive  32  directly connected to member  29  and valve  27  and connected by a gear wheel  34  to the valve  28 . The gear wheel  34  meshes with teeth on the member  29  and teeth on the support for the valve  28  so that as the member  29  moves in one direction the valve  28  moves in the opposite direction. The valve  28  is provided with a spring  28 A similar to the spring  33  for valve  27 . 
     Thus as member  29  moves to pressurise the tube  25  the valve  28  moves rearwards to permit passage of product to the nozzle  26 . A reverse movement has the opposite action and the valve  28  closes the bottom end of the tube  25 . 
     Referring to  FIGS. 5-10  there is shown an alternative to the reciprocal pushing member  29  in which product is discharged from the tube  25  by a roller  40  carried on the end of a rod  41  driven by reciprocal drive means  42 . The drive means is carried on a pivot  43  for pivotal movement of the roller  40  up and down about the pivot  43 . The roller  40  is arranged to engage the tube  25  towards the upper end of the tube to compress the tube at its upper end and then to move down the tube, compressing the tube as it passes towards the lower end of the tube. Such downward movement of the roller  40  may be achieved by the axis of the guide means and rod  41  being inclined to the horizontal and when the roller has fully compressed the tube  25  it moves downwards towards the lower end of the tube, as seen in  FIG. 6 . Alternatively, the roller may be located in a cam track  45  so that as the roller is extended it moves along the cam track  25 , initially inclined to the axis of the tube and then over portion  45 A extending in the longitudinal direction of the tube  25  ( FIG. 5 ). In each case, the roller effects movement of the product from the tube  25  and through the nozzle  26  when the valve  28  is opened. 
     In the arrangement of  FIGS. 5 and 6  it may be possible to omit the valve  27  since the roller  40  will close the upper end of the tube  25  in its initial movement and, as the roller  40  moves down the tube further product can be admitted to the upper end of the tube behind the roller. An alternative arrangement for the cam track is shown in  FIG. 5  in which the cam track itself is pivoted about its lower end at  47 . 
     It will be appreciated that the nozzle  26  is shaped to shape product being discharged, usually in a star shape to give an attractive appearance to the product. 
     It will also be appreciated that with the use of the roller arrangement  40 , the roller can pass along the tube a predetermined amount to discharge a predetermined quantity of the product which may be less than the total product contained within the tube  25 . After the roller  40  has moved a predetermined amount, the valve  28  is closed to prevent further discharge. The full sequence of emptying the tube  25  is shown in  FIGS. 6-10 . 
     The tube  25  may have at each end flanges  25 A by which the ends of the tube are located and locked in the apparatus. The nozzle  26  is arranged to be slideable into the housing and the abutment plate  35  is hinged so that upon opening the front door of the housing  10  and moving the plate away, the nozzle is removeable. 
     Instead of the tube  25  being engageable with the plate  35  it may be locatable inside a rigid housing and may be made fixed to the housing so that the tube is removeable for cleaning. It may also be arranged that the tube  25 , nozzle  26  and plate  35  are integral and removeable as a unit and made of material suitable for sanitising, such as steel or plastics. 
     The container  12  may be located on a support which, when the plunger is moved upwards clear of the container, is slideable forwards on guides (not shown) to access the container support and replace the container in its support. Alternatively the support  13  for the container  12  may be hinged to allow the support to be pivoted forwards to remove and replace the container with support  13 . 
     Turning now to  FIGS. 11 and 12  there is shown an alternative form of apparatus in which the same reference numbers are used for similar parts. Thus, there is a housing  10 , the interior of which is refrigerated by refrigeration means  11  contained in the base of the housing. A similar form of portion control mechanism is employed as for the previous embodiment including valves  27  and  28 , a pushing member  29  engaging a flexible tube  25  into which product is extruded from a container. However, in this case the container is different from the container  12  of the previous embodiment and is shown at  50  in  FIG. 12 . It is generally cylindrical and collapsible having an outlet nozzle  51  extending from one end in the lateral direction. The container  50  is for location within a cylinder  52  having a piston  53  at one end moveable along the cylinder towards the other end to compress the container  50  and cause it to reduce in volume, discharging product from the container under such pressure through the outlet  51 . In this case the piston  53  is moved by a linkage  54 , generally termed scissors or a lazy tongs linkage which is moved towards an expanded position,  FIG. 11 , by a drive arrangement  55  having a rod  56  one end of which is attached to the linkage  54  whereby upon retraction of the rod  56  the linkage  54  is expanded to move the piston along the cylinder  52 . In the operating position of  FIG. 11  the end of the cylinder  52  is closed by an abutment member  58  against which the container  50  is engaged. The nozzle  51  extends through a side opening in the cylinder  52  to lie in sealing engagement with the tube  25 . The linkage  54  is used to allow the dimensions between the front and back of the apparatus to be kept to a minimum. 
     The cylinder  52  is pivotable about a pivot  60  by operation of a drive  62  which moves the end of the cylinder remote from the outlet up and down whereby to expose the container  50  ( FIG. 12 ) from the abutment  58  and allow access to the container  50  whereby to enable the container to be removed from the cylinder  52  when empty, and for full containers  50  to be located within the cylinder  52 , when required. The container  50  is generally formed of flexible plastics material to enable it to collapse as product is discharged therefrom. In another arrangement the container is discharged by a piston within the container. 
     Referring now to  FIGS. 13A and 13B  there is shown two forms of container similar to that shown  FIGS. 1-4 , the container of  FIG. 13A  having a single outlet nozzle  39  located centrally of the base  14  of the container, the nozzle  39  tapering inwardly away from the container. The base  14  is of generally circular section and has a curved profile and extends upwardly to define a shoulder  65  and then an outwardly tapering upper portion  66  terminating in a lip  67 . The container has an upper closure member  15  of which the central portion  15 A is deformable and invertable to move downwardly into the curvilinear portion of the base  14  so that when the container is discharged fully the portion  15 A lies closely adjacent the base  14 . The outer part of the closure  15  has an upwardly directed portion  68  whose upper edge extends over the lip  67  to secure the closure  15  on the base  14  by mechanically locking. If desired the closure  15  and the base  14  are secured together by heat-sealing. This may be done after the container has been filled with product. Alternatively the closure  15  may be sealed on the base  14  before admitting product to the container in which case product is admitted to the container through the nozzle  39 . 
     Other shapes of container can also be employed, for example, rectangular with radiused corners. 
     The container of  FIG. 13B  is similar to that of  FIG. 13A  except that in this case two outlet nozzles  39  are formed in the base  14 . The twin nozzle arrangement permits apparatus to be employed in which there are two discharge paths for product from the container, as shown in  FIGS. 14A and 14B . Thus, if required two receptacles can be filled at the same time from the same container at the same or different rates and with the same or different quantities of product in each receptacle. The apparatus of  FIGS. 14A and 14B  may in other respects be similar to the apparatus of  FIGS. 1-4  except two sets of valves and discharge members are provided, one for each path of product. 
     Sauces or other additional product can be dispensed at the outlet area, for example, using a liquid pump, with the possibility of a different sauce for each outlet. 
     Referring now to  FIG. 15 , there is shown apparatus in which two containers  12  may be employed at the same time, there being two plungers  21 , one for each container, and one or two discharge paths from the two containers. If there is one discharge path then one container provides a back up for the container which is being used. If two discharge paths are provided, there may be two discharge operations which can be effected simultaneously and each container may contain different product. 
     In the arrangement with one discharge path there is provided a three way manifold valve  69  by which supply may be switched from one or other of the containers  12 , when one becomes empty, and the operation may be automatic. The front of the housing  10  is provided with doors  68  one for each side of the housing to access one or other of the individual dispensers. Dispensing may continue when the container at one side is being changed. A central division is provided between the two dispensers to prevent access to the working parts of the operational dispenser during refilling. 
     Referring now to  FIG. 16  there is shown an arrangement for use on the apparatus of  FIGS. 1-4  whereby the discharge plunger may be moved and put to one side of the container, or to the back or front of the container, between operative movements of the plunger  21 . Thus as the plunger  21  is moved upwardly from engagement from the container  12  it moves along a cam track  70  having two portions  70 A and  70 B of which portion  70 A lies along the axis of compressive movement of the plunger and portion  70 B is inclined thereto. The drive means  23  is pivotally attached at  24  so that as the plunger moves upwards a pin  71  carried on the rod  22  passes upwards along the portion  70 A and then side ways along the portion  70 B of the track, the drive  23  pivoting to one side. In the latter position, the plunger has moved to give more ready access to an empty container  12  which can then be released from the seating  13  and a full container replaces the empty one, access being obtained to the container through a door in the front of the housing  10 . 
     Referring to  FIG. 17  a similar requirement is met by the drive  23  being displaceable about axis  24  to give access to the empty container  12 , this time through a rear door  74  into the housing  10 . 
       FIG. 18  shows the drive  23  displaced rearwards, for example, by the arrangement of  FIG. 16  to give access to recharging the container  12 . 
     Referring now to  FIGS. 19A and 19B , there is shown an arrangement by which overload, or maximum selected load, in the drive  23  is detected by a simple mechanical arrangement. As shown, the drive  23  is carried on a pivot  24  carried on a rod  75 . The rod  75  in turn carries an arm  76  moveable between lower and upper switches  77  and  78 . A fixed abutment plate  79  is located on the rod  75  and a domed spring  80  extends between the fixed member  79  and the lower end of the rod  75 . Normally the spring  80  is fully extended and the arm  76  engages with the switch  77 . If the pressure in the drive  23  exceeds a predetermined high value, the pressure overcomes the resistance of the spring  80  and the rod  75  with the arm  76  moves upwards so that the arm  76  engages with the switch  78  and tells the drive that too much, or the selected pressure is being applied and switches off the drive. This situation may arise if the drive has reached the end of its travel and the container is empty. Alternatively, if the product within the container is too hard to extrude, then the drive signals this fact and interrupts the drive arrangement.  FIG. 19B  shows the drive and associated spring  80  when drive pressure has been exceeded. 
     Referring now to  FIGS. 20A-20C , there is shown a further drive overload arrangement similar to that of  FIGS. 19A and 19B  having a drive  82  and rod  83 , the drive  82  being connected at one end to a further rod  84  about which are located springs  85  and  86 , one to each side of a fixed abutment  87 , there being an arm  88  extending from the rod  84  and the arm being engageable with switches  89  and  90 . 
     Thus, on extension of the drive  82  in one direction with a force sufficient to exceed a predetermined pressure, the spring  85  will compress and cause the switch  90  to be operated. In the other direction, the spring  86  will be compressed and cause the switch  89  to be operated. This arrangement is for particular application to the apparatus of  FIGS. 11 and 12 . 
     Referring now to  FIGS. 21A ,  21 B and  21 C there is shown a further arrangement for detecting pressure overload. This is similar to those in the previous embodiments except that in this case the rod  75  has located around it two domed springs  92  and  93 , in series, which are arranged to operate at different pressures so that upon the force applied exceeding a first predetermined value, one spring  92  is compressed and at a higher predetermined pressure, spring  93  is compressed. This causes the arm  76  to operate a series of three switches  94 , 95  and  96  in sequence, thereby enabling control of the operation of the drive within three pressure parameters. More than two sets of springs can be used to give more pressure parameters. 
       FIG. 22  shows the incorporation of the drive overload system of  FIGS. 19A and 19B  in to apparatus similar to that of  FIGS. 1-4  except that in this case, the tube  25  has a simple cut off valve  97  which, when open, permits discharge of product through nozzle  26  and, when closed, prevents discharge of product from the container  12 . There is then no control of individual portions in the manner of the previous embodiment. The valve  97  simply controls the flow from the container on an off/on basis. However, there may be control of the time the valve  97  is operated thereby controlling the amount of product dispensed by preselection. 
     The overload arrangement functions to tell the operator when a container has emptied or when product within the container is too hard to be discharged. It can be confirmed whether the container is empty by linking the signal to the main drive to determine ‘empty’ as opposed to ‘too hard’. A light signal can then be used as an indication. 
     Instead of using linear or mechanical drives for the discharge of the container contents and operation of the valve and tube discharge other drive means may be employed, for example, pneumatically hydraulically on other drive media. The use of linear drives which operate at constant speeds enables the apparatus to be controlled by the position of the moveable terms and in accordance with the time for which the drives have been operating which eases the control of the apparatus. However, proximity switches can be used to detect when various operations can be performed. 
     The housing  10  is refrigerated to retain product in the container at the desired dispensing temperature. However if containers are stored in the housing and introduced at lower than dispensing temperature this will have the effect of lowering the temperature in the housing. Accordingly, the housing may have heater means as well as cooling means to heat up the internal space as well as to keep the product and the air within the housing at the required low temperature. Alternatively stored containers may be held in a compartment separate from the main body of the housing in which compartment heating can take place to raise the temperature of the product to a dispensing temperature. It is also helpful to have ventilation/circulating air within the housing. It may also be helpful to be able to select the temperature within the housing or part thereof according to the product to be dispensed when different products have different dispensing temperatures. 
     While the invention has been described in connection with what is presently considered to be the most practical and preferred embodiments, it is to be understood that the invention is not to be limited to the disclosed embodiments, but on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.