Abstract:
A vending machine apparatus ( 32 ) comprising a housing defining an internal cavity and an article storage area ( 76 ) positioned inside the cavity. The article storage area ( 76 ) has a cooling unit associated therewith for cooling the article storage area ( 76 ). A thermal barrier ( 12 ) is disposed within the housing and positioned between an outer perimeter of the article storage area ( 76 ) and the remainder of the internal cavity so as to substantially divide the internal cavity into first and second thermally separated sections ( 17   a–b ), with the cooling unit being located in the first section ( 17   a ). An opening in a portion of the housing is located in at least one of the first or second sections ( 17   a–b ), and a first air moving device is positioned in one of the first or second sections ( 17   a–b ) for causing an air flow path which removes heat developed by the cooling unit, from the first section inside the cavity.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
   This application claims priority under 35USC 120 of U.S. Provisional Patent Application No. 60/360,130 filed Feb. 26, 2002, entitled “Thermal Separating Baffle In A Vending Machine”. The entire disclosure of this patent application is incorporated herein by reference in its entirety. 

   SUMMARY OF THE INVENTION 
   The present invention provides a thermal separating baffle in a refrigerated vending machine. 

   
     BRIEF DESCRIPTIONS OF THE DRAWINGS 
     The accompanying drawings, which are incorporated herein and constitute part of this specification, illustrate exemplary preferred embodiments and details of the invention, and together with the general description given above and the detailed description given below, serve to explain the features of the invention. 
       FIG. 1  is a side section view of an exemplary vending machine useful for illustrating one embodiment of a thermal barrier constructed and operating in accordance with the principles of the present invention. 
       FIG. 2  is a simplified top section view along lines  2 — 2  of  FIG. 1 . 
       FIG. 3  is a simplified cross-section side view of a storage cabinet of the type usable in a vending machine of the type illustrated in  FIG. 1 , useful for illustrating a further aspect of the invention relating to the use of thermal barriers in a vending machine. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     FIG. 1  illustrates a prior art vending machine  10 , such as known by prior U.S. Pat. No. 5,240,139, which is modified so as to illustrate one aspect of the present invention. Machine  10  has an outer housing  11  and hinged front door  9  for forming a cabinet for the vending machine. Housing  11  includes therein a refrigerated insulated compartment  12  for storing articles to be vended. In one embodiment, refrigerated compartment  12  has associated therewith a refrigeration unit  16  and a displaceable thermal separating door  14  positioned over an opening  15  in one side, in this case the topside, of compartment  12 . Door  14  provides a thermal separation at the opening  15  between the remainder of the interior of the vending machine and the interior of compartment  12 . The above-noted U.S. Pat. No. 5,240,139 shows and describes several different embodiments for door  14 , including a single-piece hinged door which makes a vertical arcuate motion during opening/closing, as well as several “sliding” door designs. It is also noted that an “air curtain” can also form a thermal barrier that functions as a door, as well as merely having an air gap over compartment  12 , which in some situations may be sufficient for effective operation of the vending machine, since cold air sinks, and therefore tends to stay within compartment  12  when left undisturbed. Compartment  12  includes therein open-topped subdivided sections  72  adapted for storing articles  74 , such as ice cream or other frozen or refrigerated foods in a cooled environment until they are selected to be dispensed by a user of vending machine  10 . A plurality of divider walls  76  are positioned inside compartment  12  so as to form the subdivided sections  72 . 
   In operation, after a user of the vending machine has inserted the proper payment and made a valid selection of an item stored in the vending machine, a control mechanism  40  of machine  10 , of conventional design, causes an article pickup carriage  20  having a suction hose  22  and pickup head  52  hanging therefrom, to be laterally positioned over the section  72  which stores at least one of the selected articles. In the illustrated embodiment, movement of carriage  20  causes door  14  to become displaced, via cable  68  and rollers  70 , so as to provide entry and egress of article pickup head  52 . The control mechanism  40  then causes a motor in carriage  20  to operate so that the article pickup head  52  controllably enters the selected compartment  72 , suction generated by a blower motor  7  is conducted thereto via hose  22  (the full length of hose for connection to blower motor  7  is not shown in this Figure, but as one of ordinary skill in this art would realize, is required) and the selected article  74  thereby becomes secured to the article pickup head  52 . The motor in carriage  20  is operated again, this time in a reverse direction, so as to extract article pickup head  52 , and the selected article, from compartment  72 , and deposit the selected article in a customer retrieval area  16 . A customer access door  18  allows the user access to retrieve the dispensed article. 
   In view of the public availability of the above-noted patent, and the widely known construction and operation of vending machines of this type, no further description of how to make and use a vending machine of the type described so far, is considered necessary. 
   It is noted that in the illustrated embodiment, compartment  12  may comprise a “static” cooling system, such as a chest freezer, i.e., where, as well know to those of ordinary skill in the art, the refrigeration coils are located in the walls of compartment  12 . More specifically, the evaporator coil portion  12   a  (not specifically shown in detail) of the refrigeration coils will be in good thermal contact with the interior of compartment  12 , and the condenser coil portion  12   b  (not specifically shown in detail) of the refrigeration coils will be separated therefrom via thermal insulation  12   c,  and in good thermal contact with the outer walls of compartment  12 . This known type of system results in the outer walls of compartment  12  radiating the heat generated by the system into volume  32 , which, in accordance with the present invention is thermally separated from the volume in housing  11  having the opening into compartment  12 , i.e., volume  31 . Alternatively, compartment  12  could be cooled by a fan-based refrigeration system. Heat generated by compressor  16  or other portions of the refrigeration system could be more directly exhausted outside of housing  11  by appropriately positioned channeling to vent  36 . 
   With such a device, during normal machine operation, the thermal barriers between the cooled and ambient areas inside of housing  11 , in this case doors  14  and  18 , are opened and closed many times, thereby repeatedly exposing warm air from housing  11  to the cooled air in compartment  12 . Since cold air is heavier than warm air, when the door  14  is opened, the colder air tends to stay in the storage compartments  72 , however, typically there is some unwanted mixing of the ambient air with the refrigerated air at the top of the storage compartments  72 , at least partially due to air currents caused movements of the picker head, the opening and closing of door  14  and other parts of machine  10 , thereby introducing unwanted heat into the freezer. At least some of this unwanted hot air was generated by the compressor and condenser as described above. 
   It is one object of the present invention reduce this unwanted mixing of hot air in compartment  12 . 
   Accordingly, in accordance with one aspect of the present invention, a thermal insulator or baffle  19  is provided about the periphery of the compartment  12  so as to effectively form first and second thermally separate volumes  31  and  32  within housing  11 . It is noted that it is not necessary for the thermal separation provided by baffle  19  of the invention to be “leak-proof” for substantial benefits in thermal efficiency to be achieved. 
   Referring simultaneously to  FIGS. 1 and 2 , illustrating a preferred embodiment of this aspect of the invention, these volumes are shown vertically oriented. More specifically, volume  32  is located in the lower portion of housing  11  and thermally separates some of the heat generating components, such as refrigeration unit  16  and the suction generating blower motor  7 , from the remainder of the interior of housing  11 , which is located above volume  32 . Volume  31  is located in the upper portion of housing  11  and above volume  32 , and includes therein opening  15  and door  14 , which provide access into the cooled article storage areas  72 . 
   In accordance with a further aspect of the present invention, separate ventilation is provided for each of volumes  31  and  32 , comprising, for example, passive vents  34  and  36 , respectively, which allow air flow from inside housing  11  to outside housing  11 , or passive vents having powered fans (not specifically shown, but which are aligned with vents  34  and  36 ) to improve the exhaust airflow. Of course, suitable “inlet” airflow would be required if sufficient openings are not already provided, for example by the opening into the customer retrieval area  16  or near the bottom of front door  9 . 
   Baffle  19  can be attached to the inside walls of housing  11  or the outside walls of the compartment  12 , or a combination of both, in order to effectively make the separate thermal volumes  31  and  32 . 
   It is noted that for that portion of compartment  12  facing the front door  9 , the baffle can be attached to portions of the door  9  rather than the inside walls of housing  11 . It is also noted that appropriate flexibility and/or openings and/or flaps may be needed as part of baffle  19  to form an effective thermal seal around various other parts of vending machine, such as customer retrieval area  16  or an alternative type of opener for door  14 . 
   In accordance with a further aspect of the present invention, the air flow generated by a fan that is used to conduct heat away from the suction generating blower motor  7 , and/or compressor  16 , is directed to the thermal volume  32 , where it can be conducted to the exterior of housing  11  either passively or by the use of a fan, via vent  36 . Alternatively, as noted above, vent  34  could also be used if suitable ventilation ducting is provided so the exhausted heat does not adversely affect volume  31  as it passes therethrough. 
   It is noted that the cooled air which enters pickup head  52  during the dispensing operation may be directed into the thermal volume  31  or  32 , where it can be conducted to the exterior of housing  11  either passively or using fans, via vents  34  or  36 . Alternatively, since the “suction-air” substantially comprises cooled air taken from freezer  12 , thermal efficiency may benefit if this air remain inside volume  31 . 
   In accordance with an even further aspect of the present invention, compartment  12  can be mechanically mounted and electrically connected within housing  11  so as to be at least partially removable therefrom, such as by the use of sliding tracks mounted between a bottom portion of compartment  12  and housing  11 , so as to assist in repositioning of compartment  12  to be at least partially outside of housing  11  during re-loading of compartment  12  with fresh articles to be vended. If necessary, any electrical connection to compartment  12  required for operating the cooling equipment associated therewith, could be selectively disconnectable, so as to facilitate the repositioning of compartment  12 . 
   While the present invention has been disclosed with reference to certain embodiments, numerous modifications, alterations and changes to the described embodiments are possible without departing from the sphere and scope of the present invention, as defined above, and claims which follow at the end of this description. 
   For example, it is noted that the invention described herein is not limited to any specific type of article retrieving device (such as the illustrated pickup head  52 ). For example, it may be desirable for the robotic positioning mechanism to include a rotary device (R, θ) of the type including an I beam of fixed length (or telescopic sections), for establishing an “R” movement for pickup head  52 , and where pivoting of the I beam establishes a “θ” movement. Alternatively, in other environments for the invention, the pickup head positioning mechanism may include an articulated arm or scissor system, or use a totally different dispensing technique, such a the more conventional spiral wire dispenser mechanism. Other types of suitable pickup devices include a mechanical claw or scoop, a magnetic attracting device, a portable suction generator, etc. 
   Additionally, it is noted that the principles of the present invention described herein may be advantageously combined with other ones of my inventions, such as the invention described in U.S. Ser. No. 60/360,128 entitled THERMAL BARRIER FOR A REFRIGERATED COMPARTMENT IN A VENDING MACHINE, incorporated in full herein by reference. This invention provides an additional thermal barrier at the open-topped article discharge opening of each compartment  72  (called a bin  22  in this other description), the purpose of which is to also reduce the problem of heat entering the storage compartments  72  when the door  14  is open. This additional thermal barrier is able to be selectively penetrated or opened in alignment with the top of each of compartments  72  during the dispensing operation, so as to not prevent the passage of stored articles out the top of the compartments  72 , but at other times provides an additional thermal barrier over the tops of compartments  72 . 
     FIG. 3  illustrates a further aspect of invention relating to use of thermal baffles in vending machines. More specifically, in accordance with this aspect of the invention, in order to provide a simple, low cost and reliable vending machine which has storage capabilities for both frozen articles (such as ice cream or meals), as well as articles that are merely cooled to temperatures above freezing (such as chocolate confections or fresh foods), compartment  12  includes an additional thermal barrier arrangement, e.g., walls  13 , arranged therein for creating a “less cooled” environment  17   a , and an environment  17   b  which is cooled to a greater extent than environment  17   a . Environment  17   b  comprises the remainder of the interior of compartment  12 . In the embodiment where compartment  12  comprises a static freezer, walls  13  are provided in direct contact with the walls forming 3 sides (and possibly the bottom as well) of compartment  12 , and a wall  13   a  is provided so as to divide the interior of compartment  12  into environments  17   a  and  17   b.    
   It is also noted that the present invention is particularly advantageous when compartment  12  is of the type which has the evaporator coils distributed along and in thermal contact with the inside walls which form the main interior volume of compartment  12 , and the condenser coils are thermally insulated from the evaporator coils and distributed along and in thermal contact with the walls which form the outside perimeter of compartment  12 . With this type of freezer, no fans are required for the refrigeration system since the cooling effect of the evaporator coils is directly radiated to the interior of compartment  12 , and the heat generated by the refrigeration system is directly radiated by the outside walls of compartment  12  to the external environment. Such chest freezers are commonly available form many sources. 
   Note, in an alternative embodiment of the invention, contact by walls  13  to the interior walls of compartment  12  does not have to be direct, and in fact can be with as few as one of the walls used to form environment  17   a.    
   Control of the size of environment  17   a  is easily adjusted by adjusting the placement of wall  13   a , which can be facilitated by, for example, a series of preformed slots in the floor and/or interior walls of compartment  12 , which slots can be engaged by tabs (not shown) about the periphery of wall  13   a . Alternatively, the insulated walls  13  used for forming compartments  17   a  and  17   b , may comprise a pre-assembled box or tub having an open top, which can be simply placed/dropped inside compartment  12 , thereby dividing compartment  12  into the two thermally separate environments. 
   Control of the temperature inside environment  17   a  can be adjusted by appropriate sizing of the thickness of walls  13 , and to some extent, also wall  13   a . For example, a wall  13  having a thickness W 1  in contact with a cooled interior wall of compartment  12  would have twice the insulation characteristics of one having a thickness W 2 , and therefore the thickness of walls  13  can to a great extent relatively simply determine the amount of cooling provided to environment  17   a  as compared with that provided to environment  17   b.    
   Additional control of the temperature inside environment  17   a  can be provided by a vent  21  formed in a wall that is common with the frozen environment, i.e. in wall  13   a,  to allow flow of cooled air from environment  17   b  into environment  17   a . Additionally, vent  21  could include a baffle for selectively varying the size or flow rate of the opening in wall  13   a. Additionally, a powered device, such as a fan  21     a  could alter the flow rate between these environments. In this case, the baffle or fan could be controlled by a temperature sensing device mounted in environment  17   a  or  17   b , such as an electrical or mechanical thermostat. Furthermore, the vent  21  could be located at a height in wall  13   a  which is different than that show in  FIG. 3 , such as near the top. Even furthermore, vent  21 , or an additional vent, not shown, could be located in a wall of compartment  12  so as to provide a flow of ambient air from outside of compartment  12  into environment  17   a  or  17   b  in order to warm the respective environment. 
   As shown in  FIG. 3 , door  14  of  FIG. 1  could still be used over environment  17   b , and a separately operating door  14 ′ could be used over environment  17   a , to further enhance thermal efficiency. Alternatively, a commonly operating door  14  could be used without departing from the scope of the invention. 
   Even furthermore, it is noted that the “dual-temperature” cooled environment invention described herein finds advantageous use in combination with the perimeter thermal baffle invention noted above, as well as in combination with the above-noted invention described in U.S. Ser. No. 60/360,128 entitled entitled THERMAL BARRIER FOR A REFRIGERATED COMPARTMENT IN A VENDING MACHINE. Note, the principles of this aspect of the invention are equally applicable to making more than two, i.e., three or even more, thermally separated sections in article storage compartment  12 . 
   Accordingly, it is intended that the present invention not be limited to the described embodiments, but that it has the full scope defined by the above language and following claims, as well as equivalents thereof.