Fluent material handling – with receiver or receiver coacting mea – Combined
Reexamination Certificate
1998-10-30
2001-01-09
Douglas, Steven O. (Department: 3751)
Fluent material handling, with receiver or receiver coacting mea
Combined
C141S067000, C141S038000, C062S077000, C062S292000
Reexamination Certificate
active
06170541
ABSTRACT:
BACKGROUND OF THE INVENTION
The invention relates to a method of introducing a leak detection dye composition into a climate control system, and a system for introducing the dye composition into the system.
Leak detection methods have been developed to analyze fluid systems, such as climate control systems, i.e., heating, cooling, ventilating, and air conditioning systems, for leaks using dyes. Some methods employ emissive substances, such as, for example, fluorescent or phosphorescent dyes that are added to the refrigerants and/or lubricants of a climate control system. Suitable leak detection dyes include a naphthalimide dye, a perylene dye, a thioxanthane dye, a coumarin dye, or a fluorescein dye, and derivatives thereof.
Leaks can be detected by observing light emission from the dye at leak sites resulting from excitation of the dye with a light source having particular illumination characteristics (e.g., at wavelengths suitable to excite the dye and cause light emission from the dye). In general, the dyes emit brightly when excited by light in the 190 to 700 nanometer wavelength range.
SUMMARY OF THE INVENTION
In general, the invention features a leak detection dye introduction system for introducing a leak detection dye composition into a climate control system. The leak detection dye introduction system can include a housing loaded with a leak detection dye composition and an adaptor for introducing the leak detection dye composition into a transfer unit which is used to introduce the dye into the climate control system.
In one aspect, the invention features a method of introducing a leak detection dye composition into a climate control system. The method includes connecting a transfer unit to an outlet of a housing, opening the valve assembly; transferring the leak detection dye composition into the transfer unit, removing the transfer from the outlet, connecting the transfer unit to a climate control system, and introducing the leak detection dye composition from the transfer unit into the climate control system. The outlet includes a valve assembly and the housing includes a leak detection dye composition.
In other embodiments, the transferring step can include transporting the leak detection dye composition under a pressure differential from the housing into the transport unit. In yet another embodiment, the method can include the step of charging the climate control system with a refrigerant through the transfer unit.
The transfer unit can be under reduced pressure prior to being connected to the outlet. The transfer unit can be a low-side service hose. The transfer unit can include an actuating valve. Additionally, the transfer unit can be a component of a refrigerant charging unit, e.g., a refrigerant recovery and recycling system. The leak detection dye composition can have a volume of less than 0.5 ounces. The climate control system can be an air conditioning system.
In another aspect, the invention features a method of introducing a leak detection dye composition into a climate control system. The method includes loading a leak detection dye composition from a housing into a reduced pressure transfer unit, and charging a climate control system with a refrigerant through the reduced pressure transfer unit to transport the leak detection dye composition into the climate control system.
In another aspect, the invention features a leak detection dye introduction system including an adaptor having an outlet connectable to a transfer unit having an actuating valve, an inlet connected by a flow path to the outlet, the inlet being connectable to a housing containing a leak detection dye, and a valve assembly located between the inlet and the outlet the valve assembly being opened and closed by the activating valve of the transfer unit.
In other embodiments, the inlet can be threaded. Additionally, the actuating valve of the transfer unit can include a stem that actuates the valve assembly.
Typically, the housing can have a volume of less than about 1 ounce, preferably less than about 0.75 ounces, and more preferably less than about 0.5 ounces. For example, the housing volume can be between 1.0 and 0.25 ounces. In general, less than 1 ounce of leak detection dye composition is loaded into the housing. Preferably, the volume of leak detection dye composition introduced into the systems is less than about 0.75 ounces, and more preferably less than about 0.5 ounces. For example, the leak detection dye composition can have a volume between about 0.50 and 0.10 ounces (e.g., about 0.25 ounces).
The leak detection dye composition includes a leak detection dye. Examples of a dye include a naphthalimide dye, a perylene dye, a coumarin dye, a thioxanthane dye, a fluorescein dye, or a derivative thereof, or other dye compatible with climate control systems. The dye composition exhibits fluid flow. Preferably, the dye composition can be a liquid.
The leak detection dye composition can also include a refrigerant or a lubricant. The refrigerant can include chlorofluorocarbons, 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. Examples of a refrigerant include 1,1,1,2-tetrafluoroethane (R-134a, Allied Signal, Morristown, N.J.) and dichlorodifluoromethane (R-12, DuPont, Wilmington, Del.). The lubricant can include polyalkylene glycols, polyolesters, mineral oils, polyvinyl ethers, alkylbenzenes, or other synthetic lubricating materials. Additionally, the leak detection dye composition can include other additives used in climate control systems.
The climate control system can be a mobile, stationary, window air conditioning system such as an automotive, portable, residential, or commercial air conditioning system, or any other hermetic system that employs a refrigerant and lubricant.
The method of introducing a leak detection dye into a climate control system can reduce spillage of dye during injection, since the dye is transferred into the transfer unit from the housing in a sealed system. Also, by using a reduced pressure transfer unit, the risk of spilling dye is reduced. Accordingly, the introduction of dye can be cleaner. The leak detection introduction system can be used to deliver more consistent amounts of a leak detection dye into a climate control system. The leak detection dye introduction system is compact, making it easy to handle and use. The leak detection delivery system can be more efficient at delivering a fixed amount of dye composition to the system.
For example, the leak detection injection system can be used in conjunction with standard refrigerant charging units, such as refrigerant recovery and recycling systems. Thus, the leak detection dye introduction system can minimize servicing time and effort. The small volume of the leak detection dye composition used in the leak detection dye system can reduce the amount of extraneous materials (e.g., dye, extra lubricant, and extra refrigerant) introduced into a climate control system.
Additional features and advantages of the invention will become apparent from the detailed description of the preferred embodiments of the invention.
REFERENCES:
patent: 2096099 (1937-10-01), Gaugler
patent: 3785164 (1974-01-01), Wrenn
patent: 3937029 (1976-02-01), Grahl et al.
patent: 4612798 (1986-09-01), Roberts
patent: 4693118 (1987-09-01), Roberts
patent: 4938063 (1990-07-01), Leighley
patent: 5070917 (1991-12-01), Ferris et al.
patent: 5149453 (1992-09-01), Parekh
patent: 5167140 (1992-12-01), Cooper et al.
patent: 5272882 (1993-12-01), Degier et al.
patent: 5357782 (1994-10-01), Henry
patent: 5673722 (1997-10-01), Brass
patent: 5826636 (1998-10-01), Trigiani
patent: 5967204 (1999-10-01), Ferris et al.
Davis, “Pinpointing Vehicle Leaks Faster with Ultraviolet Light”, The American Society for Nondestructive Testing, Inc., Nov. 1989, vol. 47, No. 11, pp. 1248-1250.
Davis, “Pinpointing HFC-134a leaks is easy if you use the proper equipment”, Air Conditioning Heati
Bright Solutions Inc.
Douglas Steven O.
Fish & Richardson PC
Huynh Khoa
LandOfFree
Leak detection dye introduction system and method does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Leak detection dye introduction system and method, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Leak detection dye introduction system and method will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2469029