Abstract: A refrigerated transport system (20) comprises: a body (22) enclosing a refrigerated compartment. A refrigeration system (30) comprises: a charge of refrigerant; a compressor (36) for driving the refrigerant along a refrigerant flowpath (34); a first heat exchanger (38) along the refrigerant flowpath and positioned to reject heat to an external environment in a cooling mode; and a second heat exchanger (42) along the refrigerant flowpath and positioned to absorb heat from the refrigerated compartment in the cooling mode. The refrigerated transport system has a detector (232) for detecting leakage of the refrigerant.

Abstract: The seat of a suction valve of a reciprocating compressor is modified to limit the radial extent and thereby the area in which an annular oil film can be established between the valve and the valve seat. The preferred radial extent of the seating surface is 0.014 to 0.018 inches and the preferred ratio of the area of the suction valve seat to the passage therethrough is in the range of 13% to 25%.

Abstract: The seat of a suction valve of a reciprocating compressor is modified to limit the area in which an annular oil film can be established between the valve and the valve seat. The seat is configured to limit the oil film from 3% to 33% of the total inlet port opening. In a modified embodiment gas at discharge pressure exerts an opening bias to the suction valve at the end of the discharge stroke.

Abstract: In addition to seating on its valve seat during the combined compression and discharge stroke, the suction valve seats on the structure associated with the valve seat which has at least one shallow recessed area. In seating on its valve seat, the suction valve seats on the structure defining the shallow recesses to trap fluid therein. The recesses serve to reduce the area available for adhesion and the trapped fluid pressure provides an opening bias to the suction valve. If necessary, or desired, restricted communication between the compression chamber and the shallow recess can take place to provide a higher pressure in the recess at the time of transition from discharge to suction.

Abstract: A compressor having plural banks of cylinders can be operated multi-stage, single stage, plural parallel single stages and, when multi-stage, with or without an economizer. One of the low stage banks of cylinders can be unloaded to reduce the first stage output during multi-stage operation or to permit operation of a single stage when the second stage is bypassed.

Abstract: In a positive displacement compressor having a plurality of banks, operation can be multi-staged or single staged. Single stage operation can be of a single bank or plural banks in parallel. Switchover between modes of operation is under the control of a microprocessor responsive to sensed inputs. During pulldown under ambient or condenser entering air temperatures of 100.degree. F., or more, suction modulation is used to limit the suction pressure thereby permitting a switchover to two-stage operation and the use of an economizer.

Abstract: In a positive displacement compressor having a plurality of banks, operation can be multi-staged or single staged. Single stage operation can be of a single bank or plural banks in parallel. Switch-over between modes of operation is under the control of a microprocessor responsive to sensed inputs.

Abstract: In a compressor having an oil sump located therein, a restricted communication is provided between the oil sump and the suction plenum. As a result, froth generation due to a rapid pressure drop in the oil sump is reduced. A relief valve is provided to limit the pressure differential between the suction plenum and the oil sump.

Abstract: A wrist pin and wrist pin retainer are combined in a subassembly which prevents inadvertent removal of the retainer from the assembly. The subassembly is placed in a bore defined by a piston and a connecting rod with at least one annular groove formed in the bore. When the subassembly is located in the bore, the retainer coacts with the annular groove to secure the wrist pin in the bore.