Abstract: A series of check valves are disclosed for use in a scroll compressor which control and dampen the closing of the check valve to reduce noise during rapid pressure fluctuations encountered during normal operation and to control loss of gas in a discharge passage. In one check valve, a reed valve or poppet valve is employed to control the motion of a main valve to a closed position. In another check valve, suction pressure is used to reduce the closing force of the main valve. In another check valve, the main refrigerant flow passes through a converging, diverging passage to create a relatively low pressure chamber to reduce the closing force of the main valve. In another check valve, the reverse flow from the discharge plenum either does not act to close the valve or acts on a reduced surface area.

Abstract: A molded, one piece electrolytic cell head is provided which is obtained from a closed mold. The structure weighs more than 100 pounds and is comprised of bulk polymerized monomers having norbornene functionality. The structure provides improved performance over cell heads comprised of fiber glass reinforced polyester since fiber reinforcement is not required.