Abstract: In the embodiment shown, the invention comprises a suction/check valve interposed in a gas inlet channel, the channel being open at one end for communication with the atmosphere, and at the opposite end for communication with a gas compressor inlet port. The valve has a bleed hole formed therein for slowly blowing down the compressor receiver at shutdown. A second check valve is operatively interposed between the receiver and the atmosphere for depressurizing the receiver when the compressor unloads. A conduit which communicates with both valves provides a valve-operating, fluid, pilot-pressure to close off the suction/check valve, and to interdict its bleed hole, and to open the second check valve, with compressor unloading.

Abstract: The invention comprises a die-cast housing of substantially dish shape having a peripheral bolting flange for replaceable mounting thereof to the end wall of an oil-flooded gas compressor. The housing has a partition formed therein to subdivide the same into a first, gas admittance area and a second, air/oil separator and oil reservoir area. The housing has a first port formed therein opening onto the first area for admitting ambient air thereinto for conduct thereof to a compressor gas inlet port, and a second port opening onto the second area for discharging compressed gas therethrough. The second area of the die-cast housing is adapted to confine therewithin the compressed gas discharge pipe of a compressor and, therebelow, a reservoir of oil.

Abstract: In the embodiment depicted, the system comprises a gas compressing arrangement of first and second rotary compressing stages with an intercooler and an aftercooler for condensing and removing moisture from the compressed gas product. In order to cool the gas compressor, generally, and the second-stage rotor shafts in particular, the cooled, de-moisturized, compressed-gas product is used. Thus, the second-stage rotor shafts are axially bored or hollowed, and a tube is supported within the bore. The tube is through-connected with the outlet of the aftercooler to admit the cooled, compressed gas product into the bore, and, in turn, the compressed gas product is discharged from the bore. Accordingly, the cooled, compressed gas product is cycled through the bore, constantly to cool the shafts all the while that the compressor is running, or under load.

Abstract: The unloading means comprise unloading ports, and valving therefor, for step-control unloading of a gas compressor. In a first embodiment, the unloading means are provided in side walls of a rotary, positive displacement, gas compressor, and in an alternate embodiment the unloading means are disposed within end walls (of a rotary, positive displacement, gas compressor), and comprehends means for step-control of a plural-stage machine.

Abstract: The unloading means comprise unloading ports, and valving therefor, for step-control unloading of a gas compressor. In a first embodiment, the unloading means are provided in side walls of a rotary, positive displacement, gas compressor, and in an alternate embodiment the unloading means are disposed within end walls (of a rotary, positive displacement, gas compressor), and comprehends means for step-control of a plural-stage machine.