Abstract:
The extension for top of refrigerant can for dispensing without a valve is used for supplying refrigerant to the air conditioning unit of a vehicle using a conventional refrigerant charging hose. The extension allows the contents of the refrigerant can to be delivered without having to attach a conventional shutoff valve to the canister. The extension includes a seal over the opening in the refrigerant can with a valve stem that extends through the center of the seal. The extension includes an actuator cap that fits over the seal on the top of the canister. The actuator cap houses an actuator for releasing the contents of the container. The actuator has a depression tab that is hingedly connected to the interior of the actuator cap for releasing the contents of the canister into the charging hose that is secured to a threaded projection on the front of the cap.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     1. Field of the Invention  
         [0002]     The present invention relates to air conditioning apparatus, and more particularly to a refrigerant delivery assembly for delivering refrigerant to an air conditioner from a canister containing pressurized refrigerant using a standard, reusable charging hose secured to a threaded dispensing cap.  
         [0003]     2. Description of the Related Art  
         [0004]     A common technique for adding refrigerant to an automobile air conditioning unit is to connect a charging hose assembly between a suction line service fitting on the air conditioning unit and a small canister containing refrigerant, and then allowing the refrigerant to flow through the charging hose into the air conditioning unit. The conventional charging hose assemblies include a charging hose, a shutoff valve connected to one end of the hose and a disconnect coupler fitting secured to the other end of the hose. The shutoff valve is screwed onto a threaded outlet portion disposed on the top surface of the canister and the coupler fitting is secured to the service fitting on the air conditioning unit. The lever on the top of the valve is rotated to lower a piercing pin member located inside the valve. The pin member pierces the outlet portion of the canister. The lever on the valve is then rotated in the opposite direction to allow the charging hose to communicate with the interior of the canister. This allows the contents of the canister to flow through the charging hose into the air conditioning unit.  
         [0005]     Several problems exist with the current method for adding refrigerant to an automobile cooling system. One problem is that there is a high possibility of discharging an undesirable amount of refrigerant into the atmosphere. If the disconnect coupler fitting is removed before the shutoff valve is closed, all of the remaining refrigerant in the canister will escape into the atmosphere. Another problem with the current method is that it is extremely time-consuming to have to add the valve to each canister of coolant and then secure the standard charging hose onto the valve. Finally, an additional problem with the present delivery method is that is difficult to control the amount of refrigerant being added into the air conditioning unit.  
         [0006]     The following patent documents disclose inventions improving on the current automobile refrigerant delivery methods or methods and devices for discharging other materials from an aerosol type canister.  
         [0007]     Several patents disclose improved distribution caps for monitoring the amount of pressurized material being released from an aerosol type canister. European Patent 49,180, published on Apr. 7, 1982, discloses a one-piece distribution cap for a pressurized container and its assembly. United Kingdom Patent 2,097,061, published on Oct. 27, 1982, discloses an actuator cap for pressurized dispensers. U.S. Pat. No. 3,314,576, issued on Apr. 18, 1967 to Focht et al., discloses a cap for dispensing aerosols. German Patent 4,303,157, published on Aug. 11, 1994, discloses an actuating device for metering closure of a pressurized container. Each of the above caps includes an integrated push button or lever that is manually depressed to release a portion of the contents of the pressured canister. The portion of the contents that is released is regulated by the duration that the push button or lever is depressed.  
         [0008]     Several patents disclose devices for, and methods of, adding refrigerant to an automobile air conditioning unit using shutoff valves as discussed above. U.S. Pat. No. 6,385,986, issued on May 14, 2002 to Ferris et al., discloses a refrigerant charging hose assembly. U.S. Pat. No. 6,481,221, issued on Nov. 19, 2002 to Ferris et al., and U.S. patent Publication No. 2002/0189265, published on Dec. 19, 2002, each disclose an apparatus, methods and compositions for placing additive fluids into a refrigerant circuit. U.S. Pat. No. 6,360,554, issued on Mar. 26, 2002 to Trachtenberg, discloses a single can automotive air conditioner refill and treatment. Each of these patent documents discloses a device for adding refrigerant to an automobile air conditioning unit using a shutoff valve that is screwed to the top of the canister.  
         [0009]     U.S. Pat. No. 4,895,190, issued on Jan. 23, 1990 to Gillen, discloses an actuator and hose assembly for aerosol containers. The actuator includes a fluid hose having a conventional fitting at one end for coupling the hose with a fluid receiver and an actuator sub assembly coupled to the other end of the hose. The sub assembly comprises an actuator cap sealed to the top of a canister having a press down actuator for releasing the contents of the canister. The hose is connected to the actuator by a hose connector.  
         [0010]     U.S. Pat. No. 4,941,600, issued on Jul. 17, 1990 to Berriochoa et al., discloses a dispenser lock assembly for a pressurized container. The lock assembly locks the valve stem of an aerosol container in the open position. The lock assembly includes a cap with an interior recess and an actuator tab connected to the cap and extending across the valve stem within the interior recess. A hook portion is provided on a ring lock for engaging the tab when the tab is depressed to move the valve to the open position.  
         [0011]     U.S. Pat. No. 5,305,784, issued on Apr. 26, 1994 to Carter, discloses a tire inflation hose assembly. The hose assembly connects a container of pressurized tire inflation material and a valve system of a tire. The hose assembly includes a release valve assembly for coupling to the container and for releasing the pressurized material contained inside. A tube transports the released material to a nozzle that is adapted for matting with the valve stem of the tire.  
         [0012]     U.S. Pat. No. 5,611,466, issued to Hsiao on Mar. 18, 1997, discloses a releasing unit for a container in which a pressurized material is enclosed. The releasing unit has a cap a nozzle assembly with a hose portion. The nozzle assembly is engaged to a releasing valve of the container and the cap has a skirt portion mounted to a top of the container and having a slot defined in the skirt portion for the hose to extend through.  
         [0013]     U.S. Pat. No. 6,382,469, issued on May 7, 2002 to Carter et al., discloses a tire inflation actuator. The actuator has a body that is securable to container of pressurized material. The actuator includes a depressible finger tab for releasing the contents of the container and a latch for releasably securing the tab in a depressed position. A hose is secured to the actuator for delivering the contents of the container.  
         [0014]     None of the above mentioned patents disclose an actuator cap having a threaded projection for receiving the threaded connector of a conventional refrigerant charging hose.  
         [0015]     None of the above inventions and patents, taken either singly or in combination, is seen to describe the instant invention as claimed. Thus an extension for the top of a refrigerant can for dispensing without a valve, thereby solving the aforementioned problems, is desired.  
       SUMMARY OF THE INVENTION  
       [0016]     The extension for the top of a refrigerant can for dispensing without a valve is used for supplying refrigerant to the air conditioning unit of a vehicle engine. The extension for the top of the can is adapted for using a conventional refrigerant charging hose for delivering the contents of the can to the air conditioning unit. The extension also allows the same charging hose to be reused several times. The extension allows the contents of the refrigerant can to be delivered to a vehicle without having to attach a conventional shutoff valve to the top of the canister.  
         [0017]     The present invention includes a seal over the opening in the top of the refrigerant can. The seal includes an aerosol valve stem that extends through the center of the seal. The extension includes an actuator cap that fits over the seal on the top of the canister. The actuator cap houses an actuator for releasing the contents of the container. The actuator has a depression tab that is hingedly connected to the interior of the actuator cap. When a pressing force is applied to the depression tab, the valve stem is forced downward, releasing a controlled portion of the contents of the refrigerant canister.  
         [0018]     The actuator cap also has a threaded projection extending outward from its front surface. The threaded projection is adapted to receive a threaded connector on a first end of a conventional refrigerant charging hose. The charging hose is connected in fluid communication with the valve stem through a channel in the projection so that as the contents of the refrigerant canister are released, the contents are directed through the charging hose to the vehicle.  
         [0019]     Accordingly, it is a principal object of the invention to provide an extension for the top of a refrigerant canister that does not require securing a conventional shutoff valve to the top of the canister.  
         [0020]     It is another object of the invention to provide an extension for the top of a refrigerant canister that allows a conventional refrigerant charging tube to be secured to the canister and then reused with subsequent canisters.  
         [0021]     It is a further object of the invention to provide an extension for the top of a refrigerant canister that allows the user to easily regulate the portion of the canister contents that is released.  
         [0022]     It is an object of the invention to provide improved elements and arrangements thereof for the purposes described which is inexpensive, dependable and fully effective in accomplishing its intended purposes.  
         [0023]     These and other objects of the present invention will become readily apparent upon further review of the following specification and drawings. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0024]      FIG. 1  is an environmental, perspective view of an extension for the top of a refrigerant can for dispensing without a valve according to the present invention.  
         [0025]      FIG. 2  is a perspective view of the extension for the top of the refrigerant can according to the present invention.  
         [0026]      FIG. 3  is an exploded, perspective view of the extension for the top of the refrigerant can according to the present invention.  
         [0027]      FIG. 4A  is a top view of an actuator cap of the extension for the top of the refrigerant can according to the present invention.  
         [0028]      FIG. 4B  is a side cross-sectional view of the actuator cap of the extension for the top of the refrigerant can according to the present invention.  
     
    
       [0029]     Similar reference characters denote corresponding features consistently throughout the attached drawings.  
       DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0030]     The present invention is an extension for the top of a refrigerant can for dispensing the contents of the can without the use of an attachable shutoff valve. The present invention may be designed as an extension that will be added to a pre-existing refrigerant canister, or as a new refrigerant canister having the discharging extension secured to the top of the canister. According to the preferred embodiment of the present invention, the extension is designed for delivering refrigerant from a pressurized canister to the air conditioning unit of a vehicle.  FIG. 1  is an environmental perspective view of the refrigerant canister with the discharge extension  10  secured to a vehicle air conditioning unit.  
         [0031]      FIG. 2  is a perspective view of the refrigerant can with extension  10  according to the present invention. The refrigerant can with extension  10  generally comprises a pressurized fluid canister  20  with an actuator cap  30  attached to the top of the canister  20 . According to a preferred embodiment of the present invention, the pressurized fluid canister  20  contains vehicle air conditioning refrigerant.  FIG. 2  further depicts a conventional refrigerant charging hose  60  secured to the actuator cap  30 . The refrigerant can with extension  10  may be designed with the charging hose  60  integrally secured to the actuator cap  30 , or preferably, the refrigerant can with extension  10  may be designed to receive a pre-existing charging hose  60  so that the charging hose  60  may be removed and reused with subsequent refrigerant cans  10 .  
         [0032]      FIG. 3  is an exploded perspective view of the present invention  10  depicting its individual elements. The refrigerant can with extension  10  comprises the refrigerant canister  20 , a canister cover  70 , an actuator cap  30 , and an actuator cap lid  50 . The canister  20  has vertical sidewalls forming a generally cylindrical main body  20  with a sloped top end and a bottom end  22 . A canister opening  26  is disposed in the center of the top end. The top end has an upstanding rim  24  surrounding the opening  24 . The upstanding rim  24  is adapted for securing the actuator cap  30  to the can.  
         [0033]     The canister cover  70  is disposed over the opening  26  in the top of the canister  20 . The canister cover  70  has a circular lip portion  72  that is disposed around the entire circumference of the canister cover  70 . The lip portion  72  mounts the canister cover onto the upstanding rim  24  on the canister  20  to form a seal that prevents the contents of the canister  20  from escaping. The canister cover  70  has a conventional upwardly biased and extending, axially movable, tubular aerosol valve stem  74 . The valve stem  74  extends through the center of the canister cover  70  having a bottom portion  76  that extends into the canister  20 . The valve stem  74  is upwardly biased by the pressure of the contents of the canister  20 , and may also be additionally biased by a biasing means, such as a spring (not shown). The valve stem  74  is coupled inside of the canister cover  70  so that when the stem  74  is shifted or moved downwardly, the contents of the canister  20  are released. When downward pressure on the stem  74  is removed and the stem  74  is released, the stem  74  is upwardly biased by the pressure inside of the canister  20  so that it returns to its original position to prevent further release of the canister  20  contents.  
         [0034]     The actuator cap  30  comprises a generally cylindrical bottom skirt portion  31  having an overall diameter, and further comprises an upper rim portion  34  having an overall diameter that is slightly smaller than that of the bottom skirt portion  31 . The lower skirt portion  31  is adapted for mounting the actuator cap  30  onto the canister  20 . The interior of the bottom skirt portion  31  is hollow, defining an opening along the bottom edge  32  of the actuator cap  32 . The bottom edge  32  of the actuator cap  30  frictionally engages the upstanding rim  24  of the canister  20  to securely mount the actuator cap  30 .  
         [0035]     The upper rim portion  34  extends from the lower skirt portion  31  and provides an aperture or a top opening for accommodating a depressible actuator tab  36 . The upper rim portion  34  does not extend around the entire outer periphery of the actuator cap  30  in order to provide a recess in the rim portion  34 , as shown in  FIG. 3 . The recess provides access to the actuator tab  36 . The actuator tab  36  is pivotally secured to the actuator cap  30  by a flexible actuator hinge  40  (shown in  FIG. 4A ).  
         [0036]     The actuator cap  30  further comprises a threaded projection  38  that extends outwardly from the upper rim portion  34  of the cap  30 . The threaded projection  38  is adapted for receiving a threaded connector of a discharge tube for delivering the released contents of the canister  20  to the air conditioning unit of a vehicle. The threaded projection  38  includes an opening  39  that allows the released contents of the canister  20  to pass out of the actuator cap  30 . Preferably, the threaded projection  38  has a diameter of {fraction (7/16)} inches and a pitch of  20  threads/inch to accommodate an automobile air conditioning unit. For alternative applications the threaded projection has a diameter of {fraction (8/16)} or ½ inches and a pitch of  16  threads/inch. These dimensions, however, are only exemplary and do not limit the threaded projection  38 . The dimensions of the threaded projection  38  may be altered to accommodate any fastener.  
         [0037]     The actuator cap lid  50  is an openable, protective cover that is secured to the actuator cap  30 . The lid  50  has a flat top surface  54  that prevents incidental depression of the actuator tab  36  when the invention  10  is not in use. The lid  50  further comprises a open bottom portion  52  that is adapted for releasably fitting over the upper rim portion  34  of the actuator cap  30 . The lid  50  is hingedly secured to the actuator cap  30  by a hinge  55  disposed along the lid  50 .  
         [0038]      FIG. 4A  is a top view of the actuator cap  30 . The actuator tab  36  is a depressible tab that is pressed downward by the user&#39;s finger. The top surface of the actuator tab  36  includes a plurality of finger gripping grooves  37 . The gripping grooves  37  provide a frictional surface for the user&#39;s fingers. The actuator tab  36  is secured to the cap  30  by hinge  40 . The hinge  40  allows for movement of the actuator tab  36  between an unactuated position and a depressed actuated position. In the depressed actuated position the valve stem  74  is actuated to release the contents of the canister  20 .  
         [0039]      FIG. 4B  is a side cross sectional view of the actuator cap  30 . A stem receiving orifice  33  is disposed on the bottom of the actuator tab  36 . When the actuator cap  30  is positioned on the top of the canister  20 , the stem receiving orifice  33  engages the top of the valve stem  74 . The actuator cap  30  further comprises a discharge channel  35  that extends through the center of the threaded projection  38  to the discharge opening  39 . The discharge channel  35  is in fluid communication with the valve stem  74  so that as the contents of the canister  20  are released through the valve stem  74  the discharge channel  35  will transfer the contents out of the discharge opening  39 .  
         [0040]     The actuator cap  30  may optionally include an integrated locking mechanism. The locking mechanism holds the actuator tab  36  in a depressed actuated position without the user having to hold his finger on the tab  36 . The locking mechanism preferably comprises a lock hook  42  that is integrally formed in the skirt portion  31  of the actuator cap  30 . The locking mechanism also comprises a lock engaging hook  44  on the bottom of the actuator tab  36 . Once the actuator tab  36  is depressed to a certain degree, the engaging hook  44  engages the lock hook  42  to lock the actuator tab  36  in place.  
         [0041]      FIG. 3  depicts a conventional refrigerant charging hose  60 . The charging hose  60  is a conventional hose used my mechanics for delivering refrigerant to the air conditioning unit of a vehicle. The charging hose  60  comprises an elongate tubular main body  61  having a receiving end  62  and a discharge end  63 . A threaded fitting  64  is secured to the receiving end  62  of the charging hose  60 . The threaded fitting  64  engages the threaded projection  38  of the actuator cap  30 . A disconnect coupler fitting  66  is secured to the discharge end  63  of the charging hose  60 . The disconnect fitting  66  is a conventional fitting that is adapted to couple with the recharging nipple on a vehicle air conditioning unit. The canister with extension  10  may be designed with a discharge hose integrally mounted to the threaded projection  38 . This would require, however, that a new hose be used every time a new canister was used. According to one preferred embodiment of the present invention the threaded projection  38  is adapted to engage the threaded fitting  64  of a pre-existing conventional charging hose  60  so that the charging hose  60  may be removed and re-used with subsequent canisters  20 .  
         [0042]     To operate the refrigerant canister with extension  10  the user must first secure the actuator cap  30  to the top of the canister  20 . Next the threaded fitting  64  of the charging hose  60  is secured to the threaded projection  38  of the actuator cap  30 . The lid  50  is then removed revealing the actuator tab  36 . The user than depresses the actuator tab  36  to engage the valve stem  74  and to release a portion of the canister&#39;s  20  contents. The user may hold the actuator tab  36  down manually or use the locking device to hold the tab  36  in the actuated position. The present invention  10  allows the user to regulate the portion of the contents that is being released. If the user only needs to deliver a small amount of refrigerant to a vehicle, then once the desired amount of the contents is discharged, the user simply removes pressure from the actuator tab  36  and replaces the lid  50  for later use.  
         [0043]     According to certain aspects of the present invention  10 , the actuator cap  30  may be designed in two different forms. The actuator cap  30  may be made pre-attached to a new canister  20 . The actuator cap  30  may also be made as an attachment for a pre-existing canister  20 . The actuator cap  30  is capable of fitting onto any conventional aerosol type canister.  
         [0044]     It is to be understood that the present invention is not limited to the embodiments described above, but encompasses any and all embodiments within the scope of the following claims.