Abstract:
An electro-mechanical locking system for vending machine doors and the like having a function that facilitates securing a movable gasketed door and effectively seals the movable door wherein a lock assembly comprises a motor driven device that is attached to one of the movable door assembly or cabinet body and has a rotatable and translatable shaft with a bayonet end having an arrow shape end that engages a slotted stationary device that is generally located in the cabinet body. Driving members cause the translational and rotational movement of the bayonet end and are configured to move in a curvilinear or sinusoidal path so there is a smooth transition and some rotation along with translational movement.

Description:
CROSS-REFERENCE TO RELATED PATENT APPLICATIONS 
     This patent application claims the benefit of U.S. Provisional Patent Application No. 60/252,210, filed Nov. 21, 2000 and it is a continuation-in-part thereof. 
    
    
     FIELD OF THE INVENTION 
     This invention relates generally to locking devices and, more particularly, locking devices for vending machines and the like. 
     BACKGROUND OF THE INVENTION 
     Pop out and cam out lock assemblies and the like are well known art. Such assemblies are commonly used for example to prevent unauthorized access to vending machines. Vending machines being further defined as devices such as refrigerated soft drink machines, food (snack) machines, candy machines, coin changers, mass transit collection systems, storage boxes, and the like. These conventional locking devices are so well defined that dimensional standards exist for the vending industry. Several patents have been issued for modifications and improvements in the field of these devices. For example, T handles or pop-out handle devices are well known in the industry; see, U.S. Pat. Nos. 3,089,330 (Kerr), 3,550,412 (Pitel et al.), 4,552,001 (Roop), 4,760,721 (Steinbach), 4,899,561 (Myers), and 5,548,982 (Rawling). The pop-out assemblies and the like also facilitate the sealing of the gasket on many of the vending machines described above. This sealing action is derived typically from a screw type action of the threaded shaft of the pop-out handle as it threads itself into the stationary device in the cabinet structure. The force to tighten the door comes from a multiplication of hand forces that are exerted on the various designed members of the Pop-out lock. Therefore, the amount of force is very subjective and is cause for improper sealing of the vending machine. It is desirable in the industry to have the door locked and properly sealed. 
     The pop-out handle and its summary of inventions with improvements still present a clear security risk. The pop-out handle itself must be located on an exterior surface of the vending machine. The handle must be located on the exterior to allow for lock access with a variety of keys and to allow the operator to turn the screw tight in an attempt to seal the door. This allows for a variety of attack methods. Efforts to prevent unauthorized entry on machines with Pop-out handles have included adding secondary locking devices such as padlocks with hasps to effectively cover the handle or manufacturing the handle out of exotic alloys or adding steel hardened plates and the like. Each invention whilst improving the security of the basic handle still keeps the basic handle in its original form and utility. 
     The conventional pop-out handle lock assemblies include two generally T-shaped components, which cooperated to secure a movable door of a typical vending machine. More specifically, such Pop-out assemblies typically comprise of a generally T shaped housing mounted to the movable door and generally T shaped lock housing handle which is received by and nested within the generally T shaped housing. The T shaped lock handle housing has an integral handle and shell with additional provisions for a stem portion that is generally threaded. The shell is designed to facilitate the mounting of a cylindrical lock assembly. The two T shaped members are disposed so as to be secured by a lock stud that protrudes through both members. The T shaped lock handle housing includes a slot that allows the stem to disengage when the handle is pushed rearwards. 
     The movable door may be opened by rotating the lock key and causing the lock stud to retract. Further this action by retracting the T shaped lock handle housing allowing it to slide longitudinally along its axis until it engages the end of the stem. After the stem has engaged the T shaped lock handle housing the operator is free to rotate the housing. This rotation causes the screw to extend and disengage from the stationary device attached to the cabinet. After disengaging the movable door can then be opened. 
     By reversing the above process the door is secured with the following exception. The lock stud may or may not be spring tensioned to allow the T shaped handle housing to be pushed back without further action from the key or lock. 
     Because goods and currency are customarily stored within the cabinet structure there is a greater need for higher levels of security. 
     Prior art such as Myers U.S. Pat. No. 6,068,487 does provide means by which to latch and effectively pull in or seal the movable door and it does provide a reasonable level of security but it is severely restricted in applications because of complexity and cost. Major changes are required to allow fitment into vending machines and the like. Claghorn U.S. Pat. Nos. 5,813,257 and Glick 5,823.027 still use the T handle embodiment. Hyatt U.S. Pat. No. 6,005,487 provides extensive encryption and an electronic key with battery power source independent from the vending machine. 
     The present invention provides such a locking device and method of locking that is not intrusive into the vending machine, capable of being key-less electronically operated, and enables obtaining a reliable, secure seal for vending machine doors having gaskets. These and other advantages of the invention, as well as additional inventive features, will be apparent from the description of the invention provided herein. 
     BRIEF SUMMARY OF THE INVENTION 
     The invention provides an optionally key-less electronically operated bayonet locking device and method of operating the same wherein a rotatable and translatable bayonet device or means having an arrow shaped end is carried by respective ones of the vending machine door and cabinet and a stationary slotted receiving member carried by the other one of the respective door and cabinet. The bayonet device arrow shaped end enters the slottted receiving member and then rotates to secure the door and the end translates longitudinally pull in the door for effectively sealing a door gasket on the machine. The locking device is constructed so as to enable that rotation at least in the transitional phase with longitudinal translation of the arrow shaped end occurs together. 
     OBJECTS OF THE INVENTION 
     Accordingly, a primary object of the invention is provide a bayonet locking device for a vending machine or the like that can remove the point of attack from the outside of the vending machine, therefore, giving a vending machine equipped with this device a higher level of security. 
     A secondary objective is to facilitate the proper sealing of the movable door. 
     As a related object of the invention, the locking device provides a reduction in manual effort for operation, which in turn will reduce the potential for bodily injuries. 
     Also related to the sealing action is the ancillary improvement objective for keeping the temperature inside the vending machine more consistent and aiding in reducing energy consumption as well as reducing mechanical compressor failures. Related to compressor failures is the possible exposure of the environment to harmful ozone depleting gases. 
     An additional object of the invention is to allow for a variety of different access disciplines such as electrically controlled or electronically controlled, and also enabling use of a variety of commercially available communication mediums to open the movable door. Communication mediums such as IRDA, RFID, RF, IR, Magnetic cards, Smart Cards, Keypads, Cellular phone, Pager networks, Dallas ibutton, merely by way of example, can be used with the locking device of the present invention. 
     Another further object is to allow the lock to be controlled in such a manner as to indicate which key or access device was used to access the vending machine. 
     Also provided is the ability to couple with the vending machine electric supply in such a manner as to allow the vending machine to operate within prescribed wattage limitations. 
     Also embodied into the objectives is the ability to maintain the door seal for extended periods of time and not have cause to cease up or freeze the mechanism. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     In the drawings, whereas similar reference numerals denote similar elements throughout the several views: 
     FIG. 1 is a perspective view of a typical vending machine having the lock mounted thereto and incorporating the basic elements of the system. 
     FIG. 2 is an exploded perspective view of the lock assembly depicted in FIG.  1 . 
     FIG. 3 are three assembly views of the stationary device that is mounted in the cabinet depicted in FIG.  1 . 
     FIG. 4 is perspective assembly view of the lock and stationary device, as the lock would be considered open. This figure is directly respective to FIG.  6 . 
     FIG. 5 is a perspective assembly view of the lock and stationary device, as the lock would be considered as locked. This figure is directly respective to FIG.  7 . 
     FIG. 6 is a partial cross sectional view depicting relative position of internal lock components in the open state. This figure is directly respective to FIG.  4 . 
     FIG. 7 is a partial cross section view depicting relative position of internal lock components in the locked state. This figure is directly respective to FIG.  5 . 
     FIG.  8  and FIG. 9 defines one of many possible logic flow charts that allow the lock to open and close. 
     FIG. 10 is a perspective as well as a sectional view of the rotatable shaft 
     FIG. 11 is a plan view of the central cylindrical housing. 
     While the present invention will be described and disclosed in connection with certain preferred embodiments and procedures, it is not intended to limit the invention to the specific embodiments. On the contrary, it is intended to cover all such alternatives, modifications, and equivalents that fall within the spirit and scope of the present invention as defined by the appended claims. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The above objects are accomplished by providing a locking device that can be totally housed inside the cabinet and movable door structure of vending machines. The locking system is composed of two mechanical devices that interact using electronics to control the interaction that allows the vending machine to be a highly secure device. 
     The first part of the mechanical lock consists of central cylindrical housing, a rotatable shaft, and a ramped gear housing, motor drive and cross pin with rollers. The second part of the mechanical lock is the stationary device that consists of method for attaching it to the cabinet as well as a slotted plate that receives the rotatable shaft while the door is closing. 
     The locking action begins by moving the arrow shaped end of the rotatable shaft into the slotted plate on the stationary device. This action causes a movable plate that is located in the stationary device to change the state of an electrical switch. This sends a signal to a control device and activates a gear motor. The gear motor rotates the ramped gear housing and causes the pin to react with a radially slot on the central cylindrical housing. The rotatable shaft is nested inside the central housing and the pin passes through a slot that is machined parallel through the shaft. The pin is nested in such a manner as to facilitate two bearing surfaces on either side of the central cylindrical housing. As the pin moves it follows the contours of the slot located in the central cylindrical housing. The slot is curved so to allow a smooth transition from a radial motion to a parallel motion. The parallel motion causes the pin to move up the ramps located inside the ramped gear housing. This action causes the rotatable shaft to draw into the central cylindrical housing. Rollers are provided on the pin to reduce friction. The curvilinear shape of the slot in the central cylindrical housing keeps the rollers from jamming as the action transitions from radial to linear motion and provides a somewhat sinusoidal path of movement. Steel ramps are nested in the ramped gear housing. These ramps provide high wear surfaces for the pin rollers and prevents plastic failure of the ramped gear housing. The steel ramps are curved and are effectively are standing on end inside the ramped gear housing. These ramps transfer all on the compressive forces of the pin rollers to the mounting plate surface of the lock. An additional wear plate is located between the ramped gear housing and mounting plate surface of the lock. The motion of the pin as it moves up the ramp is transferred from the ramp surface to the central cylindrical housing slot, then the pin follows the slot pushing on a screw that is located in the back of the rotatable shaft. By adjusting this screw in and out of the rotatable shaft the relative position of the rotatable shaft is changed. The length of the motion is controlled by the height of the ramp surfaces. The gear motor stops when it is signaled by either an electrical switch that is located on the ramped gear housing or excessive current (wattage). The function of the rotatable shaft is further defined by using a second sensing switch on the ramped gear housing. This sensing switch detects the rotatable shaft as it begins its rotation. If the movable door is allowed to open before the rotatable shaft has rotated far enough to cause the arrow to be positioned behind the slotted plate on the stationary device the rotatable shaft will return to the position where the arrow can be removed by opening the movable door on the vending machine. 
     To unlock the door, the motor receives a signal to energize. The motor turns the opposite direction that was used to lock the movable door. The ramped gear housing rotates and the pin with rollers follows the ramp. The pin travels along the parallel surface. This action causes the rotatable shaft to extend itself. This action releases the sealing. The pin continues to follow the parallel slot until it transitions to the sinusoidal shape and begins its radial movement. This radial movement causes the rotatable shaft to turn. The turning action is stopped after the pin has run out of ramp surface or the motor turns off. There is a switch that monitors the ramped gear housing position. 
     The stationary housing on the cabinet side of the vending machine can have its slotted plate either orientated vertically or horizontally when it is allowed to receive the arrow of the rotatable shaft. The vertical shape is desirable where the movable vending door is allowed to sag over time. This sagging will have cause to make the horizontal slotted plate not functional. The vertical design also facilitates manufacturing tolerances for the movable plate. The horizontal slotted stationary device movable plate is subject to unobtainable manufacturing tolerances. 
     The third item of the locking system is considered to be the logic required to operate the gear motor. 
     The object of access medium is defined as it is embedded into the logic system above. The access mediums are generally commercially available for integration into the locking system. 
     Referring now to the drawings, there is shown in FIG. 1 a typical vending machine  10  having a stationary cabinet  20  and a movable door  30  hinged and attached thereto. As it is customary in the art, the cabinet  20  includes a product compartment chamber (not detailed) where products to be vended (sold) are stored. In addition, the movable door  30  includes provisions for the collection and storage of money collected by the sales of products contained within the vending machine. 
     The specified locking system referenced by numeral  100  is shown in FIG. 1, and as being attached to the movable door  30  using common commercial fasteners. The stationary device is referenced by numeral  200  is shown in FIG.  1 . The stationary device  200  is fastened to the cabinet  20  also using common commercial fasteners. The location of the locking system in the movable door  30  is generally opposite the hinged side of the movable door  30  and is generally centrally located on the vertical plane. 
     In the second illustrated embodiment FIG. 2 the ramped gear housing  110  is shown assembled to central cylindrical housing  120 . It is retained in place between a snap ring  122  and a larger diameter of the central cylindrical housing  120  a rear ramped cover  121  provides a surface for the snap ring  122  to rest on. The rotatable shaft  130  is shown with the bayonet end having an arrow-shaped end section/portion  131  of the rotatable shaft in the vertical position. The central cylindrical housing  120  is fastened to the mounting system  140  with a threaded fastener  123  and key slots  141  provided in the mounting system  140 . The central cylindrical housing  120  is stationary in the mounting system  140 . In FIG. 6 two steel ramp sections  125  rest on the washer  124 . The adjuster screw  132  is threaded into the rotatable shaft  130  and passes through a hole at the rear of the central cylindrical housing  120 . The gear motor drive  150  turns the worm gear  151  and that in turn rotates the ramped gear housing  110 . Two switches  160  provide electrical feed back to the logic board  170 . There are surfaces  111  on the ramped gear housing  110  that activate the switches as the ramped gear housing  110  rotates. 
     The stationary receiver unit  200 FIG. 3 is mounted into the stationary cabinet  20  as shown in FIG. 1 using the holes  203 . The slotted plate  204  receives the bayonet end arrow section  131  as shown in FIG. 4. A moveable plate  201  is pushed rearward by the arrow section  131  which causes the movable plate  201  to rotate about the axle  205  and activates the switch  202  activating the gear motor  150  as shown in FIG. 2. A flat spring  206  that is nested in both sides of the receiver unit having two curved shapes allows the slotted plate  204  to move horizontally both directions. After the arrow section  131  is removed from the stationary receiver unit  200 , the flat spring will reposition the slotted plate  204  about its original centerline position as it relates to the stationary receiver  200 . This movement allows for horizontal manufacturing tolerances for both the cabinet  20  and the door  30  as the lock  100  and the stationary receiver  200  are mounted. The vertical slot in the slotted plate  204  allows for vertical tolerances. 
     In FIG. 5 the ramped gear housing  110  has continued to rotate causing the arrow section  131  of the rotatable shaft to move horizontally. The specific action will be detailed in subsequent sections. After the arrow section is horizontal the rotatable shaft  130  moves longitudinally into the central cylindrical housing  120 . 
     Two rollers  181  are positioned about pin  180  in FIG.  6 . Pin  180  passes through the central cylindrical housing  120  and a longitudinal slot in the rotatable shaft  130 . The rollers  181  provide anti-friction and wear areas for the pin  180  and the steel ramps  125  as the unit operates. 
     The pin  180  is positioned in an L shaped slot  131 FIG. 11 in the central cylindrical housing  120 . In FIG. 6 it is shown resting in place at what is to be considered as the base of the L shape slot  131 . 
     As the gear motor  150  activates it rotates the worm gear  151  this causes the ramped gear  110  to rotate. This in turn causes the pin  180  to move radially around the base of the L shape slot  131  in the cylindrical housing  120 . This causes the arrow section  131  to rotate. As the ramped gear  110  continues to rotate the pin  180  makes contact with the side of the L shaped slot  131 . The pin  180  then begins to move up the side of the L shaped slot  131  because the steel ramps  125  pushes the pin longitudinally. This longitudinal action was described earlier in this embodiment so as to describe its utility for this application. The shape of the L shaped slot  131  is conceived in such a manner as to prevent the rollers  181  from jamming as the pin  180  transitions from radial movement to a longitudinal direction. 
     The pin  180  actually facilitates the pushing action on the rotatable shaft  130  through the adjuster screw  132 . While it is possible to have the pin  180  push on the end of the longitudinal slot in the rotatable shaft  130  it is desirable to allow for adjustment. 
     The longitudinal slot  134  in FIG.  6  and FIG. 10 is closed on both ends of the rotatable shaft. A threaded hole is provided through the centerline of the shaft intersecting the longitudinal slot  134  on the end opposite of the arrow portion  131  of the rotatable shaft. The longitudinal slot  134  provides the area for driving the rotation of the rotatable shaft. A chamfer  135  area is required to the prevent plastic deformation of the slotted area  134  of the outside diameter of the rotatable shaft  130  in reaching the inside bore diameter of the center cylindrical housing  120 . A common compression spring (Not shown) is provided on the end of the rotatable shaft  120  and is housed inside the center cylindrical housing  120  at the end where the adjuster screw  132  is located. This spring provides a cushion effect when the mechanism is considered unlocked or open. That is to say when the arrow portion  131  of the rotatable shaft  130  is vertical. 
     FIG. 8 Flow-chart indicate the unlock to locked event and vise versa. The control of the lock as it described in this embodiment may use a variety of methods to control it. While electronics (solid-state) type of controls are the current acceptable methodology the logic can be controlled with electromechanical relays. Communication signals to control the lock may derive from any number of means as described earlier. 
     All references, including publications, patent applications, and patents, cited herein are hereby incorporated by reference to the same extent as if each reference were individually and specifically indicated to be incorporated by reference and were set forth in its entirety herein. 
     The use of the terms “a” and “an” and “the” and similar referents in the context of describing the invention (especially in the context of the following claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. Recitation of ranges of values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g., “such as”) provided herein, is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention unless otherwise claimed. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the invention. 
     Preferred embodiments of this invention are described herein, including the best mode known to the inventors for carrying out the invention. Of course, variations of those preferred embodiments will become apparent to those of ordinary skill in the art upon reading the foregoing description. The inventors expect skilled artisans to employ such variations as appropriate, and the inventors intend for the invention to be practiced otherwise than as specifically described herein. Accordingly, this invention includes all modifications and equivalents of the subject matter recited in the claims appended hereto as permitted by applicable law. Moreover, any combination of the above-described elements in all possible variations thereof is encompassed by the invention unless otherwise indicated herein or otherwise clearly contradicted by context.