Abstract:
The reliability of a compressor may be improved by affixing an inertia-increasing member to the drive shaft of the compressor in order to reduce the forces imposed on a mechanical coupling between the drive shaft and a compression member when the rotation of the drive shaft is initiated. A method of selecting the size and configuration of the inertia-increasing member is also provided.
Abstract:
A compressor with a capacity modulation system includes a compression chamber, a rotatable shaft within the compression chamber, and a roller mounted on the shaft in contact with a wall of the compression chamber. A suction channel is in fluid communication with the compression chamber for providing fluid at a suction pressure and a discharge channel is in fluid communication with the compression chamber for removing fluid at a discharge pressure. A re-expansion channel adjacent to the compression chamber has a first end forming a re-expansion port in the wall of the compression chamber. A re-expansion chamber is connected to the re-expansion channel. A valve disposed in the re-expansion channel is movable between a first position, in which the valve allows fluid communication between the compression chamber and the re-expansion chamber, and a second position, in which the valve prevents fluid communication between the compression chamber and the re-expansion chamber. The compressor operates in a reduced capacity mode with the valve in the first position, and in a full capacity mode with the valve in the second position. In one embodiment, the valve operates in response to a parameter internal to the compressor, such as fluid pressure. In another embodiment, the valve operates in response to a parameter internal or external to the compressor, such as temperature or fluid pressure. A further embodiment utilizes multiple re-expansion chambers to achieve varying levels of capacity reduction.
Abstract:
A pressure equalization method and system is provided for starting a compressor while maintaining the condenser at a high pressure and includes a valve and a bleed port. The compressor has a compressor inlet for receiving a fluid at a first pressure and a compressor outlet for discharging the fluid at a second pressure, and is operable to compress the fluid from the first pressure to the second pressure. The valve is proximate to and in fluid communication with the compressor outlet and is movable to an open position when the compressor is operating to permit the fluid at the second pressure to flow through the valve and is movable to a closed position when the compressor stops operating to prevent backflow of the fluid at the second pressure through the valve toward the compressor inlet. The bleed port is upstream of the valve and in fluid communication with the compressor inlet to equalize the pressure of the fluid contained in the compressor when the compressor stops operating.
Abstract:
A two stage reciprocating compressor and associated HVAC systems and methods are disclosed. The reciprocating compressor includes a crankshaft having an eccentric crankpin, a reversible motor for rotating the crankshaft in a forward and a reverse direction, and an eccentric, two position cam rotatably mounted over the crankpin. The crankshaft and cam combine to cause the piston to have a first stroke when the motor operates in the forward direction and a second stroke when the motor operates in the reverse direction. The cam and crankpin also include stabilization means to restrict the relative rotation of the cam about the crankpin. A lubrication system is provided to lubricate the engaging surfaces of the crankshaft and cam and between the cam and the bearing surface of the connecting rod. There is also provided a control for selectively operating the motor either in the forward direction at a first power load or in the reverse direction at a reduced second power load. A protector for the motor is also provided. In addition, the application of the reciprocating compressor to both air conditioning and heat pump systems is disclosed.
Abstract:
A pressure equalization method and system is provided for starting a compressor while maintaining the compressor at a high pressure and comprises a valve and a bleed port. The compressor has a compressor inlet for receiving a fluid at a first pressure and a compressor outlet for discharging the fluid at a second pressure, and is operable to compress the fluid from the first pressure to the second pressure. The valve is proximate to and in fluid communication with the compressor outlet and is movable to an open position when the compressor is operating to allow the fluid at the second pressure to flow through the valve and is movable to a closed position when the compressor stops operating to prevent backflow of the fluid at the second pressure through the valve toward the compressor inlet. The bleed port is upstream of the valve and in fluid communication with the compressor inlet to equalize the pressure of the fluid contained in the compressor when the compressor stops operating.