Ultrasonic sensor for detecting the dispensing of a product

#1. Field of the Invention

#The present invention pertains to the art of vending machines and, more particularly, to an ultrasonic sensor for detecting passage of a product container to a delivery portion of the vending machine.

#2. Discussion of the Prior Art

#FIG. 1 is a plan view of a vending machine showing a main door in an open position exposing internal structure of the machine including an ultrasonic vend sensor arranged in a product delivery chute in accordance with the present invention;

#FIG. 2 is an enlarged view of the product delivery chute of the vending machine of FIG. 1 showing the particular arrangement of the vend sensor of the present invention;

#FIG. 3 is a exploded view showing the vend sensor of the present invention;

#With initial reference to FIG. 1, a vending machine 2 includes a cabinet frame 4 having top, bottom, side and rear walls 6–10 that collectively define a central cavity 14. In a manner known in the art, a first pair of wheels or casters 16 and 17 are secured to a front edge portion of bottom wall 7 to facilitate the positioning of vending machine 2. Of course it should be realized that a second pair of wheels (not shown) are also arranged on a rear portion of bottom wall 7. A door 18 is pivotally mounted to cabinet frame 4 to selectively enable access to central cavity 14 in order to load various product containers or other commodities into vending machine 2. Door 18 is provided with a locking mechanism, shown in the form of a threaded rod 19, to retain door 18 in a closed position so as to prevent pilfering of the commodities from central cavity 14. Door 18 is also provided with an opening 20 to enable a consumer to remove a vended product container or other commodity from vending machine 2.

#Central cavity 14 includes a storage section 21, a dispensing section 22, a delivery section 24 and a lower section 26. Storage section 21 is provided to hold products in escrow until a vending operation is performed. Towards that end, storage section 21 is provided with a plurality of vertically extending column walls 32–36 which, together with side walls 8 and 9, form a plurality of column or stack areas 40–45. In the embodiment shown in FIG. 1, stack areas 40–45 constitute single stack columns. However, it should be understood that the present invention also encompasses vending machines having multi-stack columns. In any event, stack areas 40–45 are partitioned by walls 32–36 to contain, separate and support a plurality of generally cylindrical containers 49 which, in the embodiment shown, constitute soda cans.

#As further shown in FIG. 1, dispensing section 22 is provided with a frontal support wall 60 having arranged thereon a plurality of vend motors, one of which is indicated at 65. As will be discussed more fully below, a plurality of cradles (not shown) are arranged behind frontal support wall 60. Actually, each column or stack area 40–45 is provided with an associated cradle (not shown) that is operated through a respective one of the plurality of vend motors 65. Upon selection of a particular product container 49 or other commodity, one of the plurality of vend motors 65 is activated to rotate a respective cradle causing a product container 49, corresponding to the selected product to emerge from vending machine 2. That is, product container 49 is transported to a product delivery chute 70 provided in delivery section 24 which is exposed to opening 20 in door 18. In order to maintain containers 49 in a refrigerated state, lower section 26 is provided with a cooling system 75. In general, the above description is provided for the sake of completeness and to enable a better understanding of the invention. The present invention is particularly directed to the incorporation of a vend sensor for detecting that a product has been dispensed from vending machine 2.