Abstract: A method for joining an inlet/outlet pipe to a heat exchanger core in which a standard coupler of stepped cylindrical shape is first brazed integrally to the core. A unique pipe is then attached inside the outer end of the coupler purely mechanically, with a compression ring that is forced axially over the outside of the coupler to compress the inner surface of the coupler against the outer surface of the pipe. The axial force is applied between the ring and an integral bead on the coupler, so as to protect the coupler braze joint from damage.

Abstract: In order to reduce refrigerant leakage from an automotive air conditioning system, the leakage paths are kept sealed by automatically reducing the output of a variable displacement compressor (12) after initial operation of the engine for a predetermined number of five minutes, and then only for a predetermined number of ten seconds, that is, so long as there has been an air conditioning on signal by the operator. After the reduction in output for ten seconds, the output of the compressor (12) is returned to full output for a predetermined number of two air-conditioning minutes, which is then followed by another ten seconds of reduced output.

Abstract: A blowoff valve assembly includes a diaphragm separating a refrigerant connection from an ambient port open to the atmosphere. The refrigerant connection is preferably connected to air conditioning system such that the diaphragm is in contact with refrigerant from the system. The diaphragm is deflectable based on the pressure of the refrigerant and is operatively connected to a switch. When pressure of the refrigerant drops to a predetermined level, the diaphragm deflects to activate the switch. Additionally, the assembly also includes a detonable squib that explodes and ruptures the diaphragm, allowing the refrigerant to flow from the refrigerant connection to the atmosphere. Additional features, such as sensors for detecting refrigerant outside of the system, a collision subsystem, and an associated controller are also disclosed.

Abstract: Each blow-off valve includes a valve body with a first movable wall defining a portion of the liquid fluid passage therein and a second movable wall defining a portion of the suction fluid passage therein. An actuator interconnects the movable walls for simultaneously moving the walls and opening the fluid passages in response to the electrical leakage-warning signal. In the species of FIGS. 2 and 3, the movable walls are integrally united with the valve body and include frangible sections that are fractured by an explosive squib to separate the movable walls from the body to simultaneously open the liquid and suction fluid passages. In the species of FIG. 5, the movable walls are separate valve elements disposed in a circular bore that opens the passages to the ambient surroundings. The actuator includes a spring, for biasing each of the valve elements out of its respective bore, and a holding device that weakens in response to the electrical leakage-warning signal.