Vehicle air conditioning charging hose assembly and method

Air conditioning charging hose assembly and method allows for quick, safe and reliable air conditioning system testing and charging. The assembly includes a shut-off valve positioned proximate the supply fitting to allow a technician to quickly shut-off the refrigerant gas supply. The method also allows the technician to test the vehicle air conditioning system pressure when charging as the hose assembly is connected to the air conditioning system and when disconnected from the air conditioning system, allows the technician to determine the refrigerant gas canister pressure.

FIELD OF THE INVENTION

The invention herein pertains to an assembly and method to quickly, efficiently test and charge air conditioning (AC) systems and particularly pertains to an assembly and method for vehicle air conditioning systems.

Servicing air conditioning (AC) systems, especially for automobiles and other vehicles has become increasingly frequent, costly and competitive in recent years. Practically all U.S. cars and trucks are now equipped with air conditioning systems and it is recommended that these systems have at least annual testing and maintenance including charging to insure proper operation.

In order to provide proper and accurate testing and servicing of vehicle air conditioner systems, various types of tools and equipment have been manufactured to aid technicians, retail customers and others to insure proper servicing. In commercial shops and garages it is conventional to purchase refrigerant gas canisters which are threaded onto a hose assembly which is then connected to the vehicle air conditioning system for charging. The canister is punctured thereby releasing the refrigerant gas which flows generally through a hose and a gauge into the vehicle AC service port inlet. Typical hose assemblies are shown such as in U.S. Pat. Nos. 6,385,986 and 6,609,385 ('385) of Ferris et al., U.S. Pat. No. 6,978,636 of Motush et al. and U.S. Pat. No. 6,360,554 of Trachtenberg. These devices generally have a refrigerant gas canister fitting and a service port coupler whereas Motush et al. and Ferris et al. ('385) further include a gauge. Ferris et al. ('385) also utilizes a check valve downstream of the gauge. While these and other prior devices work well under normal circumstances additional features are desired to promote efficiency and save time, labor and to increase the safety of the servicing technician.

For these and other reasons the present invention was conceived and one of its objectives is to present an air conditioning charging hose assembly and method of use which includes a quick-turn shut-off valve positioned between the refrigerant supply fitting and the service port inlet coupler for quickly terminating the flow of refrigerant gas from the canister.

It is another objective of the present invention to provide a method for a service technician to more accurately test and charge a vehicle air conditioning system.

It is still another objective of the present invention to provide an air conditioning charging hose assembly having a gauge and shut-off valve which is conveniently located to allow the technician to pressure test both the refrigerant gas canister and the vehicle air conditioning system without having to always disassemble or disconnect the air conditioning charging hose assembly.

It is a further objective of the present invention to provide an air conditioning charging hose assembly which is relatively inexpensive to produce and which is safe and easy to use.

SUMMARY OF THE INVENTION

The aforesaid and other objectives are realized by providing an air conditioning charging hose assembly and method particularly for use on vehicle air conditioning systems. The preferred hose assembly is provided with a service port inlet coupler, a first hose section, a pressure gauge with charge markings on the face, a second hose section, a shut-off valve and a refrigerant supply fitting with a rotatable needle and knob for connection to a refrigerant gas canister. The hose assembly with the shut-off valve in a closed position is connected by the service port inlet coupler to a vehicle air conditioning system. A refrigerant gas canister is then threadably connected to the refrigerant supply fitting. The gas cannister may supply refrigerant gases, oil, dyes or other additives to the air conditioning system. The needle of the supply fitting is rotated by the knob to puncture the seal of a refrigerant gas canister whereby the shut-off valve can be opened to allow refrigerant gas to flow from the canister into the hose assembly and vehicle air conditioning system. A quick-turn shut-off valve is positioned at the end of the second hose section proximate the refrigerant supply fitting to allow the user to quickly discontinue the refrigerant gas flow into the vehicle air conditioner system as needed after the canister is punctured and before exhaustion. The quick-turn shut-off valve also allows the technician to remove or change the cannister without removing the hose assembly from the vehicle air conditioning system, thus preventing loss of refrigerant gases into the environment.

The method of use allows the hose assembly to remain connected to the vehicle air conditioner system while supplying refrigerants and/or testing the pressure of either the vehicle air conditioning system or the refrigerant gas canister since the quick-turn shut-off valve is positioned on the hose between the pressure gauge and the refrigerant supply fitting.

In another embodiment of the invention the refrigerant supply fitting includes a fixed needle which penetrates or punctures the refrigerant gas canister seal as the canister is threaded into the supply fitting.

In a further embodiment, the charging hose assembly does not include a pressure gauge for economy purposes.

For a better understanding of the invention and its operation, turning now to the drawings,FIG. 1shows preferred air conditioning charging hose assembly10having first flexible hose section11connected at one end to conventional service port inlet coupler14and standard pressure gauge13with a face15with charge (zone) markings16indicating a low charge (low pressure), a normal charge or overcharge connected to the other end. Charge markings16may be indicated by numbers, colors or both. Service port inlet coupler14is a conventional quick coupler which is normally closed but other embodiments such as a normally open service port coupler may be employed depending on the particular manufacturer and system to be serviced. Service port inlet coupler14engages standard inlet25of vehicle air conditioning system28(shown schematically) for fluid flow therebetween. Second flexible hose section12is connected at one end to pressure gauge13and shut-off valve22having finger lever24connected to the other end. Shut-off valve22is connected to and in fluid communication with refrigerant gas supply fitting17having knob19for threadably connecting to a standard refrigerant gas supply such as refrigerant gas canister20which may supply refrigerant gases, oil, dyes or other additives to air conditioning system28.

Refrigerant supply fitting17includes internal threads for receiving threaded outlet21of refrigerant gas canister20. Refrigerant supply fitting17includes a standard rotatable solid fitting needle18having knob19for rotating needle18to extend and thereby puncture the seal (not shown) of refrigerant gas canister20allowing the flow of refrigerant gas around solid needle18from canister20through hose assembly10into vehicle air conditioning system28. Refrigerant gas cannister20has a threaded top with standard puncture type seal for use with supply fitting17which could be replaced with a supply fitting (not shown) for use with a “snap-on” cannister (not shown) having a usual mechanical or manual gas release valve such as used on spray paint cans.

Shut-off valve22positioned at the proximal end of second flexible hose section12is joined to and in communication with supply fitting17. Second hose section12is likewise connected at its distal end to standard pressure gauge13. Typical shut-off valve22includes finger lever24for quick and easy manual manipulation to start or stop the flow of refrigerant gas from canister20. Shut-off valve22is a typical “quick-turn” shut-off valve in that finger lever24only rotates about ¼ turn from a fully open position to a fully closed position. Quick action shut-off valve22allows for rapid response and convenient control while supplying usual refrigerant gas such as R134a (not seen) from refrigerant gas canister20to inlet25of vehicle air conditioning system28. Shut-off valve22allows a technician to remove canister20or change refrigerant gas canisters without removing hose assembly10from air conditioning system28, thus preventing the harmful release of refrigerant gases into the atmosphere.

When service port inlet coupler14is removed from inlet25, service port inlet coupler14closes which allows refrigerant gas canister20to be pressure tested with quick-turn shut-off valve22opened by reading markings16on face15of pressure gauge13.

Quick-turn shut-off valve22is positioned for convenience and rapid operation and easy adjustment of refrigerant gas flow, thus allowing a technician to more precisely add the correct amount of refrigerant gas to charge air conditioning system28. Further, servicing is faster and safer in that the refrigerant gas flow from refrigerant gas canister20can be cut-off quickly by finger lever24of shut-off valve22, if necessary. In addition, quick-turn shut-off valve22allows hose assembly10to remain joined to refrigerant gas canister20after charging or testing is completed. Shut-off valve22further allows the technician to check the pressure of air conditioning system28while refrigerant gas canister20is connected and during the process of charging vehicle air conditioning system28. When shut-off valve22is closed by lever24, the pressure of vehicle air conditioning system28is tested and as necessary, shut-off valve22can be opened by lever24to finish charging air conditioning system28from refrigerant gas canister20.

In the method of servicing a typical air conditioning system, such as vehicle air conditioning system28, hose assembly10is connected to air conditioning system28by connecting service port inlet coupler14to inlet25with shut-off valve22closed by finger lever24. With hose assembly10so connected, pressure gauge13is read to determine the pressure of refrigerant within vehicle air conditioning system28. Next, if system28is low on refrigerant as determined by the test, a canister of conventional refrigerant gas such as canister20is then threadably joined to supply fitting17as shown inFIG. 1. Once refrigerant gas canister20is threaded thereon, knob19is rotated allowing fitting needle18to puncture and penetrate the seal (not shown) of refrigerant gas canister20. Next, finger lever24of quick-turn shut-off valve22is rotated ¼ turn to the open position, allowing gas from refrigerant gas canister20to flow through second hose section12, pressure gauge13, first hose section11, through service port inlet coupler14into inlet25and into vehicle air conditioning system28for charging. Once air conditioning system28has been sufficiently charged shut-off valve22is then closed to stop the flow of refrigerant gas and pressure gauge13is read to test the pressure of vehicle air conditioning system28. Should the pressure be insufficient shut-off valve22is opened by lever24to again supply refrigerant gas from canister20to system28. This step in the charging process is repeated until pressure gauge13supplies a desired reading from system28as determined by the technician. Once pressure gauge13reaches its required reading, shut-off valve22is closed and service port inlet coupler14is thereafter disconnected from inlet and automatically closes. The pressure of refrigerant gas remaining in canister20can then be tested by opening shut-off valve22and markings16of gauge13read and if empty canister20can be removed from supply fitting17and properly discarded. However, if refrigerant gas canister20is not empty and can be used again, shut-off valve22is closed to retain the refrigerant gas in canister20and hose assembly10can be stored with canister20still attached until another air conditioning system charging is needed.

InFIG. 2, alternate charging hose assembly30is seen which is identical to charging hose assembly10except that supply fitting32includes fixed hollow needle33seen in dashed lines. Shut-off valve22with finger lever24, hose sections11and12, gauge13and service port inlet coupler14are all identical to those shown in preferred hose assembly10described above. As earlier explained, supply fitting32is threaded onto threaded outlet21of refrigerant gas canister20allowing fixed hollow needle33to rotate into and penetrate the seal (not seen) of canister20, permitting refrigerant gas flow therethrough.

A third embodiment of the charging hose assembly is seen inFIG. 3. Here no pressure gauge is provided on hose41of charging hose assembly40. Shut-off valve22is available for use during the air conditioning system charging process. Hose assembly40is more economical to purchase but somewhat limits the technicians use and requires other equipment for air conditioning system pressure testing.