Abstract: A scroll-type refrigeration compressor is disclosed which incorporates an efficient, reliable, low cost modulation system employing a single actuator to effect switching between full and reduced capacity operation. The modulation system of the present invention includes an elongated member movably supported on the non-orbiting scroll which operates to ensure simultaneous opening and closing one or more unloading passages thus avoiding the possibility of even transient pressure imbalances between opposed compression pockets during operation of the compressor. In one embodiment, the elongated member has the opposite ends interconnected by springs and is rotatably movable to effect the intended modulation. In another embodiment, the elongated member is movable generally along a radial line of the non-orbiting scroll member.

Abstract: An improved capacity modulation system for scroll-type compressors is disclosed in which a valve body of a solenoid valve assembly is secured to the inner wall of the hermetic shell and the actuating coil is mounted on the outer surface thereof. The actuating coil includes a plunger/valve member which cooperates with passages provided in the valve body to selectively actuate the capacity modulation arrangement utilizing compressed fluid. The construction offers the advantage that all fluid pressure lines are located within the hermetic shell and thus protected from potential damage, the solenoid coil may be easily changed/replaced to accommodate different available operating voltages and/or malfunction thereof and the system can be easily tested prior to final welding of the outer shell.

Abstract: A scroll-type compressor having a capacity modulation system of the delayed suction type is disclosed which incorporates a valving ring rotatably supported on one of the scroll members. Seals are provided acting between the valving ring and scroll member which serve to effect a fluid tight sealing relationship therebetween when the compressor is operating in a full capacity mode thus reducing the need for maintaining tight tolerances during manufacture of the valving ring.

Abstract: A valve assembly has a discharge valve member and a suction valve member. One of these valve members includes a reed valve. The reed valve has a tab which includes a slot which engages a cantilevered pin. The cantilevered pin allows flexing of the pin upon contact with the reed valve. In addition, the cantilever mounting of the pin provides a lubricant reservoir for lubricating the interface between the pin and the reed valve.