referring now to the drawings and particularly to fig1 a dispensing apparatus according to the present invention is shown generally at 10 to comprise a generally box - like housing 12 having a housing closure 14 removably mounted to the upper portion thereof for access into the interior of said housing . the apparatus 10 is seen to be conveniently disposable on a service shelf . a dispensing station 16 is seen to be provided in an external face of the housing 12 , the dispensing station 16 being also shown in fig2 and 4 to comprise a splash guard 18 of substantially semi - cylindrical conformation , the splash guard 18 having a perimetric flange 20 for mounting said guard 18 to adjacent surface portions of the face of the housing 12 . the dispensing station 16 further comprises a platform 22 having a perforated drain plate 24 disposed thereover , a use container or cup into which a beverage is to be dispensed being disposable on the drain plate 24 in a position suitable for dispensing of a dry beverage base powder and a reconstituting liquid or extraction medium into the container for mixing therein . a hot water selector 26 and dry beverage base powder selectors 28 , which selectors can comprise &# 34 ; push &# 34 ; buttons , are positioned on the face of the housing adjacent the dispensing station 16 . activation of a product selector 28 provides both the necessary powder and water for preparation of a desired beverage while the hot water selector 26 will deliver only hot water when required for other dietary purposes . referring now particularly to fig2 the housing 12 is seen to contain a warm air flow subsystem shown generally at 30 , a dry beverage base powder containing and dispensing subsystem shown generally at 40 , a dry beverage base powder delivery subsystem shown generally at 50 , and , as shown in fig4 and 5 , a water supply subsystem shown generally at 60 . the warm air flow subsystem 30 is seen to comprise a convection tube 32 which can be l - shaped to provide a horizontally directed output at 34 of warm air heated within an air inlet chamber 36 by a resistance heating element 38 , air being drawn into the air inlet chamber 36 from externally of the housing 12 to be heated in a known fashion by the heating element 38 . warm air exiting the chamber 36 rises through the convection tube 32 and is directed into a primary warm air chamber 80 defined by a cylindrical chamber housing 82 . a lower end portion of a conical housing 84 extends into the chamber 80 through an upper end portion of the housing 82 , the conical housing 84 partially defining a secondary warm air chamber 86 in cooperation with a substantially cylindrical upper housing portion 88 formed unitarily with the conical housing 84 . a plurality of delivery chutes 90 are disposed within the secondary warm air chamber 86 , lower end portions of the chutes 90 extending from the lower open end of the conical housing 84 and into the primary warm air chamber 80 . a cover 92 of substantially cylindrical conformation is seen to be open at the lower end thereof and closed at the upper end , the cover 92 being received over the cylindrical upper housing portion 88 to further define the secondary warm air chamber 86 . the cover 92 is provided with a diametric upstanding plate 93 on the upper closed end portion thereof with the upper edge being arcuate and provided with a notch 94 . a pivotal u - shaped fastening member 96 is mounted on an interior structural portion of the housing 12 and engages notch 94 for releasably holding the cover 92 in place over the cylindrical upper housing portion 88 . the cover 92 and the housing portion 88 have cutout portions 98 and 99 , respectively , which align to allow extension of free end portions of auger - containing delivery tubes 100 , said free end portions of said delivery tubes 100 further extending into the secondary warm air chamber 86 through a cutout portion 102 in each of the delivery chutes 90 . containers 42 store the dry beverage base powders dispensed by the apparatus 10 into the use container shown in phantom at 104 in fig2 . each of the containers 42 contains a dry powder useful as a beverage base for producing a given beverage when mixed with a suitable liquid in the use container 104 . a powder metering mechanism 44 is provided beneath each of the containers 42 , the metering mechanism 44 preferably comprising a motor - driven auger 46 such as can be better seen in fig3 . each auger 46 is housed within an auger housing 48 , which auger housing 48 communicates at one end with one each of the delivery tubes 100 , each auger 46 extending into the interior of each of the delivery tubes 100 . at the other ends of the auger housings 48 , electrically driven motors 49 are mounted for power rotation of the augers 46 on selection of the appropriate dry beverage base powder selectors 28 , said selectors 28 being electrically connected through appropriate electrical relays to the motors 49 . as can be particularly seen in fig2 the interior of each of the containers 42 communicates with the interior of the auger housing 48 surmounted by said containers 42 , dry beverage base powders contained within the containers 42 being gravity fed into said auger housings 48 . therefore , on actuation of one of the augers 46 , a quantity of the dry beverage base powder contained within the surmounting container 42 is caused to be displaced into the associated delivery tube 100 and dispensed from the end of said tube 100 into the associated delivery chute 90 . the dry powder thus dispensed into the delivery chute 90 is gravity - fed from the lower end of said chute 90 through output nozzle 52 disposed beneath and aligned with the lower ends of the delivery chutes 90 , the dry powder being thereby discharged into the use container 104 . as will be described hereinafter , liquid discharged into the use container 104 for mixing with the dry beverage base powder dispensed as indicated hereinabove exits the water supply subsystem 60 through a conduit 62 , the free end of which extends through the output nozzle 52 into surmounting relation to the use container 104 . as can further be seen in fig2 the upper ends of the delivery chutes 90 extend above the delivery tubes 100 to prevent accidental discharge of dry powder from any one of the delivery tubes 100 into any one of the delivery chutes 90 not immediately associated with said delivery tube 100 . as can further be seen in fig2 each delivery chute 90 has a tab member 108 , a notch 110 being formed between the body of the delivery chute 90 and the tab member 108 , the notch 110 receiving a wall segment of the cylindrical upper housing portion 88 thereinto to suspendibly mount the delivery chutes 90 within the chamber 86 . the warm air exiting the convection tube 32 causes the temperature in the primary warm air chamber 80 to be approximately 50 degrees f . over ambient temperature . the heated air within the primary chamber 80 heats the lower ends of the delivery chutes 90 and further heats the conical housing 84 and upper housing portion 88 to provide a temperature within the secondary warm air chamber 86 of approximately 10 degrees f . over ambient . the flow of warm air through the primary chamber 80 also provides a positive pressure within the secondary chamber 86 , ambient air having moisture or other contaminant present therein being therefore prevented from moving into the secondary chamber 86 through the opening in the lower portion of the conical housing 84 through which the lower ends of the delivery chutes 90 extend . the structure thus described provides a temperature gradient between the lower ends of the delivery chutes 90 and the upper ends thereof , the delivery tubes 100 extending into the second chamber 86 and usually containing dry beverage base powder therewithin being at a lower temperature than the temperature within the primary chamber 80 to prevent deterioration of said powder . as can further be seen in fig3 an auger shut - off switch 106 is provided to prevent dispensing of the dry beverage base powders contained within the containers 42 during periods when the apparatus 10 is unattended . as can further be seen in fig3 the delivery chutes 90 are preferably formed substantially as frusto - conical sections , the upper ends of the chutes 90 being of a larger diameter than are the lower ends of said chutes . referring now to fig6 the cover 92 can be seen in detail to be held over the secondary chamber 86 by the fastening member 96 , free ends of the fastening member 96 being mounted for rotation by means of fixed mounting tabs 112 attached to interior structural portions of the housing 12 . referring once again to fig2 the perforated drain plate 24 is seen to be spaced from planar interior portions of the platform 22 , said interior portions of the platform 22 comprising a spillage reservoir which may be connected to a drain ( not shown ), water spilled within the confines of the platform 22 flowing through the apertures in the plate 24 and into the reservoir portion of the platform 22 for containment therein . the reservoir portion of the platform 22 is intended to be of sufficient volumetric capacity to contain at least a full single discharge of water from the conduit 62 . referring now particularly to fig4 and 5 , the water supply subsystem 60 is seen to comprise a hot water storage tank 54 having a heater element 56 disposed therein , the heater element 56 being thermostatically controlled in a known manner . relatively cold water is supplied to the tank 54 from externally of the housing 12 through a water inlet supply line 58 having an inlet valve 64 disposed in said line 58 for controlling the flow of water into the tank 54 . as water enters the tank 54 through the supply line 58 , heated water is caused to rise in a riser tube 68 until a syphon tube 62 is caused to be primed . at this point , the hot water flowing out of the syphon tube 62 equals the cold water entering the tank 54 through the supply line 58 except for a small portion of water which flows through a make - up orifice 70 through a lower wall portion 71 of a make - up reservoir 72 defined by partition 73 located within riser tube 68 . when the valve 64 is closed , hot water will continue to be run until the water in the riser tube 68 is below the inlet of the syphon tube 62 , at which time the heater element 56 can be activated to cause the water in the tank 54 to expand and rise within the riser tube 68 . water entering the make - up reservoir 72 through the orifice 70 is maintained therein until needed to make - up water lost through evaporation such as occurs during extended inoperative periods . effectively , the use of a relatively small riser tube 68 results in a very short elapsed time between the opening of the inlet valve 64 and the flow of hot water through the syphon tube 62 . further , the present structure provides a relatively short time between the opening of the inlet valve 64 and the discontinuation of flow through the syphon tube 62 while maintaining a large capacity with the ability to provide a rapid &# 34 ; first drink response &# 34 ; due to the presence of make - up water within the make - up reservoir 72 . a vapor relief tube 74 is vented to ambient through the housing 12 . a thermostat 76 is seen to control actuation of the heater element 56 . further , a deflector 78 acts to maintain the relatively cold water entering the tank 54 in the lower portions of said tank 54 on entry of the water into said tank . referring again to fig2 the housing closure 14 is seen to have lids 114 for each of the containers 42 permanently attached thereto , the lids 114 being formed of a flexible plastic material . the lids 114 are each seen to have an upwardly extending annular flange 116 formed thereon , the flanges 116 abutting and sealing with perimetric upper edge portions 118 of the containers 42 . it is to be understood that the containers 42 , and thus the lids 114 , can be formed in a square , rectangular , cylindrical , or other cross section as desired . the containers 42 are seen to extend at the upper ends thereof through openings 120 formed in a deck plate 122 comprising an upper internal structural portion of the housing 12 . vertically oriented flange members 124 are disposed about perimetric edges of the openings 120 . the containers 42 are seen to have downwardly extending flange members 126 formed about the upper portions thereof and extending from the exterior surfaces of said containers 42 , the flange members 124 being received within a recess defined by the flange members 126 and external surfaces of the upper portions of the containers 42 spaced from said flange members 126 . therefore , the mating flange members 124 and 126 effectively seal the openings 120 to prevent spillage of dry beverage base powder into the interior of the apparatus 10 when the containers 42 are filled with said dry powders . accordingly , all of the containers 42 are exposed for inspection and refilling on opening of the housing closure 14 , closing of the housing closure 14 bringing the lids into closing relation with the containers 42 in a single movement . since this dispenser will be used in hospital pantries , it will most likely be mounted beneath a shelf between adjacent equipment or articles thus necessitating that the dispenser be moved forwardly for refilling the canisters or for other service . in order to accommodate such movement , the water supply is through a metal reinforced flexible tube rather than standard copper tubing which will break when repeatedly bent . also , a limited direction wheel system is provided for facilitating outward and inward movement of the dispenser . the wheels 13 have a brake ( not shown ) which renders the wheels immobile when the dispenser is in use . the tracks 15 support the dispenser on a support surface of lower shelf 17 . slides similar to conventional drawer slides may also be used to support the dispenser beneath a shelf , on a counter top or any other surface such that lateral movement will be prevented thereby preventing pinched fingers when moving the dispenser in relation to a pantry shelf or the like . the product strength ( ratio of product to water ) adjustments are made by altering the auger rather than the time cycle and there is only one cold beverage selection and two hot beverage selections which enables a unique control circuit to be used . one hot beverage selection is active when the unit is at rest so that when the push button is depressed , a hot beverage will be dispensed . this reduces the control problem to selection between one hot and one cold beverage as the water select relay is normally in the hot water mode . the cold beverage selection push button actuates a second relay which deenergizes the hot water select relay to enable tap water to flow directly to the use container thus enabling the control arrangement to use only two relays or relay switches ( not shown ) to provide four selections with each push button also operating a timer for controlling the product motor or coil . the foregoing is considered as illustrative only of the principles of the invention . further , since numerous modifications and changes will readily occur to those skilled in the art , it is not desired to limit the invention to the exact construction and operation shown and described , and accordingly , all suitable modifications and equivalents may be resorted to , falling within the scope of the invention .
automatic dispensing apparatus for dispensing predetermined quantities of different beverages from one dispensing station , the invention comprises a housing having a water supply subsystem located therein for supplying either hot or cold water to the dispensing station for ejection into a cup , the housing further having a plurality of dry powder beverage base containers , each container having a powder metering mechanism for ejecting a predetermined quantity of powder into a delivery chute , the delivery chute directing the powder into the cup for mixing with the hot or cold water . portions of the powder metering mechanisms remote from the containers and upper portions of the delivery chutes , one delivery chute being provided for each container to avoid cross - contamination , are disposed within a warm air enclosure to prevent moisture contamination of the dry powders . a warm air flow subsystem heats the warm air enclosure and , by producing a positive pressure therein relative to ambient pressure at the lower ends of the delivery chutes , prevents the movement of moisture - laden air upwardly through the delivery chutes into contaminating contact with the container and the dry powders contained therein .