Abstract: A check valve is provided which may be integrated into a scroll compressor that prevents static cohesion sticking forces between a valve disc member and a retainer member of the check valve housing. Such static cohesion sticking forces may be particularly generated due to oil mist generation in such scroll compressors which create a thin lubricant film between the valve disc and the stop plate of the check valve housing, creating suction type static cohesion when dislodgment of the valve disc away from the stop plate is attempted. A relief region is created between the retainer and the valve disc creating a minimal contact surface area that greatly reduces and/or eliminates such static cohesion sticking forces. For example, the valve disc may be dished to have a concave surface that faces the retainer element provided by the stop plate.

Abstract: A compressor includes a slide valve (24) having a passage that can be in fluid communication with a discharge plenum (22) and a suction plenum (20). The slide valve (24) position may be axially adjusted to control an amount of refrigerant that is compressed between a male rotor (14) and a female rotor (12) in the compressor based upon a system control scheme that determines capacity demand. The passage (28) is in fluid communication with the discharge plenum (22) and the suction plenum (20) when the slide valve is in a fully unloaded position or a partially unloaded position. A compressor housing blocks an opening to the passage when the slide valve (24) is in a fully loaded position. The location of the opening (36) in the slide valve determines what point in axial travel of the slide valve that fluid bypass begins.

Abstract: A compressor (20) has an unloading slide valve (100). The valve has a valve element (102) having a range between a first condition and a second condition, the second condition being unloaded relative to the first condition. A piston (124) is in a cylinder (128) and mechanically coupled to the valve element. A control valve (40; 42) is coupled to a headspace (138) of the cylinder to selectively expose the headspace to a fluid source (144), pressure of fluid in the headspace producing a force on the piston and valve element in a direction from the second condition toward the first condition. The compressor includes means (190, 192; 210; 220) for relieving excess pressure in the headspace.

Abstract: A compressor includes a slide valve (24) having a passage that can be in fluid communication with a discharge plenum (22) and a suction plenum (20). The slide valve (24) position may be axially adjusted to control an amount of refrigerant that is compressed between a male rotor (14) and a female rotor (12) in the compressor based upon a system control scheme that determines capacity demand. The passage (28) is in fluid communication with the discharge plenum (22) and the suction plenum (20) when the slide valve is in a fully unloaded position or a partially unloaded position. A compressor housing blocks an opening to the passage when the slide valve (24) is in a fully loaded position. The location of the opening (36) in the slide valve determines what point in axial travel of the slide valve that fluid bypass begins.

Abstract: A check valve is provided which may be integrated into a scroll compressor that prevents static cohesion sticking forces between a valve disc member and a retainer member of the check valve housing. Such static cohesion sticking forces may be particularly generated due to oil mist generation in such scroll compressors which create a thin lubricant film between the valve disc and the stop plate of the check valve housing, creating suction type static cohesion when dislodgment of the valve disc away from the stop plate is attempted. A relief region is created between the retainer and the valve disc creating a minimal contact surface area that greatly reduces and/or eliminates such static cohesion sticking forces. For example, the valve disc may be dished to have a concave surface that faces the retainer element provided by the stop plate.

Abstract: A compressor (20) has an unloading slide valve (100). The valve has a valve element (102) having a range between a first condition and a second condition, the second condition being unloaded relative to the first condition. A piston (124) is in a cylinder (128) and mechanically coupled to the valve element. A control valve (40; 42) is coupled to a headspace (138) of the cylinder to selectively expose the headspace to a fluid source (144), pressure of fluid in the headspace producing a force on the piston and valve element in a direction from the second condition toward the first condition. The compressor includes means (190, 192; 210; 220) for relieving excess pressure in the headspace.

Abstract: A compressor is powered by a motor which is, in turn, powered by a variable speed drive (VSD). The voltage/frequency relationship of the VSD may be adjusted dynamically to maximize efficiency or permit performance within a compressor performance envelope otherwise unavailable in view of the VSD and motor.

Abstract: The annular piston of a rolling piston compressor coacts with a groove in valving action such that the groove serves as a supplemental discharge flow area but gas therein is prevented from constituting part of the suction flow. The groove may be in the motor end bearing and/or pump end bearing and permits flow from the compression chamber to the interior of the piston which is in fluid communication with the interior of the shell while the compression chamber is undergoing discharge.

Abstract: There is disclosed a flow controller-flow sensor combination especiably suited for gas chromatograph applications wherein a transducer monitors the pressure at the inlet and outlet of a flow restrictor element in the controller thereby to monitor the differential pressure across the restrictor; the differential pressure being proportional to the gas velocity through the flow restrictor element. In one form of the invention, a second flow restrictor element is provided in one input line to the transducer which preferably is of relatively low impedance in order to delay the buildup of the pressure head of the corresponding input of the transducer sensor, thus to enable the pressure at the outlet of the flow restrictor in the controller to buildup gradually so as not to exceed the maximum differential pressure specifications for said transducer.