Abstract:
The invention features a method and device for introducing fluid material into a climate control system. The fluid material can include a lubricant or a leak detection additive. The device includes a housing having an exit orifice and a housing holder having a trigger. Multiple doses of fluid material can be delivered to systems using the same housing. The method and device can allow a user to provide more economical, faster and cleaner service than with smaller volume systems, because, for example, less time is used to change the housing, eliminating or reducing contact with the fluid material and contamination of the work environment with the fluid material. The housing holder is compact and lightweight due to the absence of an external support structure holding the housing.

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates to a method and device for introducing fluid material into a climate control system, in particular an air conditioning system. 
     Leak detection additives can be used to detect leaks in fluid systems, such as climate control systems, hydraulic systems, engine oil systems, automatic transmission systems, fuel systems, brake systems, or radiator coolant systems. Climate control systems include heating, cooling, ventilating, and air conditioning systems. Some leak detection additives are emissive substances such as, for example, fluorescent or phosphorescent dyes. Suitable leak detection additives used in climate control systems include naphthalimide dyes, perylene dyes, thioxanthane dyes, coumarin dyes, or fluorescein dyes. Leaks can be detected by observing light emission from the dye at leak sites by exciting the dye with a light source having suitable wavelength or intensity. In general, the dyes fluoresce brightly when excited by light in the 190 to 700 nanometer wavelength range. 
     A variety of systems have been developed to introduce leak detection dyes into air conditioning systems. For example, previous injector designs include flow-chamber systems and syringe-type systems for introducing liquid dyes into the system. A flow-chamber system generally has a reservoir into which a leak detection dye solution is poured or a dye capsule is loaded and sealed. A carrier is then passed through the reservoir to transport the dye into the system. A syringe-type system generally has a chamber that is loaded by pouring the leak detection dye into the chamber or is preloaded by the manufacturer. The dye is then forced from the chamber into the closed system. Other injector systems include mist diffusers. 
     SUMMARY OF THE INVENTION 
     The invention features a method and device for introducing fluid material into a climate control system. The fluid material can include a lubricant or a leak detection additive. The device includes a housing having an exit orifice and a housing holder having a trigger. The housing can contain a large volume of fluid material relative to a controlled delivery volume of fluid material delivered from the device with a single motion of the trigger. The controlled delivery volume delivered to the system using the device is a relatively small portion of the large volume in a full housing. As a result, multiple doses of fluid material (e.g., up to 60 doses) can be delivered to systems using the same housing. Delivery of multiple doses of fluid material from the housing can result in more economical, faster and cleaner service than with smaller volume systems, because, for example, less time is used to change the housing. This can eliminate or reduce contact with the fluid material and contamination of the work environment with the fluid material. In addition, the exit orifice can be adapted to attach to many different fittings, adding to the flexibility of the system. The housing holder is compact and lightweight due to the absence of an external support structure to hold outer portions of the housing. Moreover, the size of the housing is not limited by the presence of an external support. 
     In one aspect, the invention features a fluid material delivery device. The device includes a housing having an exit orifice, a side wall, a movable plate within the housing in contact with the side wall, and a driver receiving end having a recessed region. The movable plate is externally accessible through the driver receiving end. The device also includes a housing holder having a handle, a trigger that moves relative to the handle, a housing receiver engaged with the driver receiving end, and a driver capable of moving the movable plate. The housing receiver includes a housing support substantially positioned within the recessed region and between the driver and the side wall. The driver includes a push rod attached to a pusher. The pusher is positioned within the driver receiving end and contacts the movable plate. The trigger is mechanically coupled to the driver such that the push rod moves the pusher and the movable plate when the trigger moves toward the handle. The device also includes a friction sleeve surrounding and slideably contacting the push rod within the housing holder and a stop that maintains the friction sleeve within the housing holder. 
     In another aspect, the invention features a housing holder of a fluid material delivery device. The housing holder has a handle, a trigger that moves relative to the handle, a housing receiver capable of engaging with a driver receiving end of a housing, and a driver capable of moving a movable plate of the housing. The housing receiver includes a housing support capable of being substantially positioned within a recessed region of the housing and between the driver and a side wall of the housing. The driver includes a push rod attached to a pusher. The pusher is capable of being positioned within the driver receiving end and capable of contacting the movable plate and the trigger being mechanically coupled to the driver such that the push rod moves the pusher when the trigger moves toward the handle. A friction sleeve surrounds and slideably contacts the push rod within the housing holder and a stop that maintains the friction sleeve within the housing holder. 
     The housing can include a locking tab. The housing receiver can include a locking lug. When the housing is engaged with the housing receiver, the locking tab is removably secured to the locking tab, for example, by twisting the housing into the housing receiver. The housing holder can include a compressible gasket between the driver receiving end and the housing receiver. The gasket can seal the housing to the housing holder. The exit orifice of the housing can be engageable with a high pressure side refrigerant port or a low pressure side refrigerant port. The exit orifice can include a one-way flow valve. The one-way flow valve can help prevent the system from pressurizing the housing due to internal system pressure. The housing can contain a lubricant or a leak detection additive, such as a naphthalimide dye. 
     The housing holder can include a handle and a trigger that moves relative to the handle. The driver can includes a push rod attached to a pusher. The pusher can be positioned within the driver receiving end, contacting the movable plate. The trigger is mechanically coupled to the driver such that the push rod moves the pusher and the movable plate when the trigger moves toward the handle. The trigger can be pivotally connected to the handle. In preferred embodiments, the housing holder can include a friction sleeve surrounding and slideably contacting the push rod within the housing holder. The housing holder can also include a stop that maintains the friction sleeve within the housing holder. The housing holder can contact the housing only at the driver receiving end. 
     In another aspect, the invention features a method of introducing a fluid material into a component of a climate control system. The method includes forcing the fluid material from the fluid material delivery device into the component. The fluid material exits the housing through the exit orifice. The method can include attaching the housing to the housing receiver by inserting the driver receiving end into the housing receiver and rotating the housing relative to the housing receiver to secure a locking tab of the housing with a locking lug of the housing receiver. In preferred embodiments, the method includes attaching the exit orifice of the housing to a high pressure side refrigerant port or a low pressure side refrigerant port of an assembled climate control system. 
     In another aspect, the invention features a leak detection kit including the housing, which can be loaded with a leak detection additive, a housing receiver, a hose assembly for attaching the housing to a climate control system, and a lamp, such as an ultraviolet lamp for detecting the leak detection additive. The kit can also include adapters for attaching the housing to a variety of systems and light filtering eye-wear that can help enhance detection of leaks. Examples of suitable lamps and eye-wear are described, for example, in U.S. Pat. Nos. 5,959,306, 5,742,066 and 5,674,000. The kit can be housed in a case. 
     Additional features and advantages of the invention will become apparent from the detailed description of the invention. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective diagram depicting a housing and a housing holder. 
     FIG. 2 is a perspective diagram depicting a fluid material delivery device. 
     FIG. 3 is a schematic diagram depicting a cutaway view of a fluid material delivery device. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     The method and device of the invention can be used to introduce fluid material, such as a lubricant or leak detection additive, into a climate control system. The climate control system can be a heating, ventilating, refrigeration, or air conditioning system. The air conditioning system can be a mobile (e.g., automotive, portable, residential), or commercial air conditioning system. The air conditioning system can be charged with a refrigerant, which can include hydrochlorofluorocarbons, hydrofluorocarbons, carbon dioxide, ammonia, halogenated or ether derivatives of methane or ethane, or halogenated ether or cyclic derivatives of propane, butane, pentane, or other hydrocarbons. The system can also include a lubricant. 
     Suitable fluid materials that can be introduced into climate control systems using the device and method of the invention include a lubricant, such as a polyalkylene glycol (e.g., a polyethylene glycol), mineral oil, alkyl benzene, polyvinyl ether, or a polyol ester or a leak detection additive. Other fluid materials can be delivered to other systems using the device, including: oils; transmission fluids; glues, epoxys and other adhesives; antifreeze; glycol; water; brake fluid; hydraulic oil; or fuel. The leak detection additive can include a naphthalimide dye, a perylene dye, a coumarin dye, a thioxanthane dye, or a derivative thereof. 
     Referring to FIGS. 1 and 2, fluid material delivery device  10  is constructed of housing  20  and housing holder  21 . Housing  20  can be made of molded plastic, such as polyethylene or polypropylene. Housing  20  can be a single-use (disposable) or refillable cartridge. Housing  20  has exit orifice  22 , through which the fluid material contained in housing  20  flows when the device is operated. Exit orifice  22  is engageable to the climate control system. In particular, exit orifice  22  can couple to a high pressure side refrigerant port or a low pressure side refrigerant port, for example, via a hose. By using various adapters, exit orifice  22  can couple to an R 134   a  high side or low side port, a 14 mm connector, a 14 mm male port, a 14 mm female port, a ¼ inch male flare port, a ¼ inch female flare port, a ⅜ inch male flare port, a ⅜ inch female flare port, a ½ inch ACME male port, or a ½ inch ACME female port. Exit orifice  22  includes one-way flow valve  24 . One-way flow valve  24  can be a check valve that prevents pressure in the system from backing up into device  10 . 
     Referring to FIGS. 1-3, housing  20  also includes side wall  26  and driver receiving end  28 . Locking tabs  30  are present at driver receiving end  28 . Locking tabs  30  removably attach housing  20  to housing holder  21 . Housing receiver  32  of housing holder  21  engages driver receiving end  28 . Locking lugs  34  are part of housing receiver  32  that removably secures to locking tabs  30 . As depicted in FIG. 2, when driver receiving end  28  is inserted into housing receiver  32  by the motion shown in arrow A, and housing  20  is then rotated relative to housing receiver  32  by the motion shown in arrow B, thereby securing housing  20  to housing receiver  32 . 
     Housing holder  21  also includes driver  36  that is capable of forcing the fluid material from housing  20 . Driver  36  has push rod  37  attached to pusher  38 . Housing holder  21  includes handle  39  and trigger  40  that moves relative to handle  39 , moving driver  36  toward housing  20 . Housing holder  21  contacts housing  20  only at driver receiving end  28 , allowing housing holder  21  to be compact and lightweight due to the absence of an external support structure to hold the housing. The size of housing can be constrained by the length of driver  36 . 
     Referring to FIG. 3, housing  20  contains fluid material  42 . Fluid material  42  is held in housing  20  by movable plate  44 , which is located within housing  20 , contacting and sealing with side wall  26 . The seal between movable plate  44  and side wall  26  prevents fluid material  42  from leaking. Compressible gasket  46  forms a seal between driver receiving end  28  and housing receiver  32 . 
     Driver receiving end  28  has recessed region  48  which allows movable plate  44  to be externally accessed. Driver  36  extends into recessed region  48  so that pusher  38  contacts movable plate  44 . Driver  36  is capable of exerting pressure on and moving movable plate  44 . Trigger  40  and handle  39  are pivotally attached via pin  45 . Stop  47  and stop  49  limit the range of motion of trigger  40  with respect to handle  39 . Spring  50  bias trigger  40  toward stop  47 . Trigger  40  is mechanically coupled to driver  36  such that push rod  37  moves pusher  38  toward housing  20  when the trigger and handle assembly is squeezed. 
     The positions of stop  47  and stop  49  regulate the distance that pusher  38  can move, which thereby controls the amount of fluid material  42  that is forced from housing  20  during a single squeezing stroke. The positions of stop  47  and stop  49 , and the diameter of housing  20  are selected so that a single squeeze of trigger  40  deposits sufficient leak detection additive in the system to detect leaks. Stop  47  and stop  49  are positioned so that a single, complete squeeze of the trigger expels ⅙ ounce of fluid material from housing  20 . Housing  20  can contain 10 ounces of fluid material so that  60  applications of fluid material can be delivered from housing  20 . Squeezing trigger  40  forces fluid material  42  from fluid material delivery device  10  and into a component of the climate control system. 
     When trigger  40  is moved toward handle  39 , ratchet pawl  52  engages with ratchet teeth  54  on push rod  37 , moving pusher  38  into housing  20 . Ratchet pawl  52  is pivotally mounted to trigger  40  for releasable engagement with ratchet teeth  54 . Spring  56  biases ratchet pawl  52  into engagement with ratchet teeth  54 . Squeezing trigger  40  and handle  39  together causes driver  36  to move toward housing  20  and when trigger  40  is released, ratchet pawl  52  advances along ratchet teeth  54 . Driver  36  can be reset by releasing ratchet pawl  52  from teeth  54 , for example, by rotating push rod  37 , and pulling rod  37  away from housing  20 . Motion of pusher  38  toward housing  20  exerts pressure on movable plate  44 , which forces fluid material  42  from housing  20  as trigger  40  moves toward handle  39 . 
     Housing support  60  is positioned within the recessed region and between push rod  37  and side wall  26 . Housing support  60  can assist in aligning housing  20  with driver  36 . Outer edge  62  of housing support  60  is close to the inner portion of side wall  26 . The clearance between outer edge  62  and side wall  26  is between about 0.005 inch and 0.030 inch, preferably between 0.010 inch and 0.020 inch. The clearance is less than the flange of locking tabs  30 . Comer  63  of housing support  60  is even with or extends beyond locking lugs  34 . The position of corner  63  and outer edge  62  hold housing  20  in place when pressure is being exerted by pusher  38  to force fluid material  42  from housing  20 . When housing support  60  is not present, the pressure of pusher  38  allows side wall  26  of housing  20  to bend inward slightly, which causes locking lugs  34  and locking tabs  30  to slip or break. As a result, housing  20  can detach from housing holder  21 . Slippage can occur at a pressure of about 30 psi. When housing support  60  was present so that comer  63  was even with locking lugs  34  and the clearance between outer edge  62  and side wall  26  was about 0.040 inch, pressures of 80 psi were tolerated without causing housing  20  to slip or break. When comer  63  extends beyond locking lugs  34 , and the clearance is decreased, even higher pressures can be sustained. These increased operating pressures allow the device to deliver fluid materials to climate control systems cleanly and accurately, even with higher pressures in the system. 
     Housing holder  21  also includes friction sleeve  70 , which surrounds and slideably contacts push rod  37 . Stop  72  maintains friction sleeve  70  within housing holder  21 . Push rod  37  slides through friction sleeve  70  when trigger  40  is squeezed. If ratchet pawl  52  is not engaged with teeth  54 , friction sleeve  70  prevents movement of driver  36  by gravity. 
     While the description above refers to particular embodiments of the present invention, it will be understood that many modifications may be made without departing from the spirit thereof. The accompanying claims are intended to cover such modifications as would fall within the true scope and spirit of the present invention. 
     The presently disclosed embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims, rather than the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.