Abstract: A method of assembling and manufacturing a laminated rotor is provided which uses laminations having a thin bridge thickness. Different techniques are provided for preventing the molten material used in the casting or injection molding operation from leaking or seeping between the laminations during casting. In one technique, the laminations are stacked and oriented in the conventional way, and then both axial and radial pressures are applied to the stacked laminations to hold the laminations in position for the casting process. In another technique, the laminations are formed or extruded with a lip or collar portion that fit in a countersunk portion of an adjacent lamination and forms a wall or barrier between the laminations to prevent the leakage of the molten material during the casting or injection molding operation.

Abstract: A resistive muffler attenuates sound generated by the gas intake and suction valve during compressor operation of a refrigerant compressor. The resistive muffler is assembled inline with the suction gas flow of the compressor and is positioned within the compressor housing. The resistive muffler attenuates the sound generated by the compressor during its operation as refrigerant gas is drawn into the compressor from an evaporator and passes through the resistive muffler in transit to the suction valve and hence to the region of the compressor where the gas is physically compressed. The resistive muffler includes a muffler housing having an intake end and an exhaust end. An acoustic foam assembly is incorporated into the muffler housing.

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 rotary compressor having a housing with a motor and an internal accumulator located on the low pressure side and an oil sump located on the high pressure side. A sealing means positioned within the housing defines a first low pressure chamber and a second high pressure chamber. The sealing means substantially maintains the pressure differential between the chambers by segregating high pressure fluid in the high pressure chamber from low pressure fluid in the low pressure chamber. The fluid entering the housing is separated into a gas portion and a liquid portion, the liquid portion being directed downward toward the motor to provide cooling for the motor while the gas portion is directed to a compressor portion through a channeling means internal to the compressor housing. The liquid portion collects above the sealing means.

Abstract: A three phase motor starting system is provided to reduce the in-rush current to the motor in order to obtain a soft start of the motor. The soft start of the motor equates to reduced impact forces on motor parts and device components connected to the motor during startup of the motor, especially a startup resulting from a reversal of the direction of rotation of the motor. The system uses an impedance load in series with the motor windings of the motor to reduce the in-rush current to the motor windings, which results in a reduced acceleration of the motor shaft and a soft start to the motor. The impedance loads used by the system can be a resistive load, a capacitive load or an inductive load, depending on the type of impedance load that is desired for the soft start of the motor.

Abstract: A control system is provided for generating discrete stepped output capacities in a refrigeration system. The refrigeration system is preferably a multi-evaporator system having two or more multi-capacity compressors. The multi-capacity compressors can be any kind of reciprocating compressor or scroll compressor that can provide two or more different output capacities. The contributions of the compressors to the overall system capacity can be equal, or more preferably, they can be unequal, i.e., one compressor provides more capacity than the other compressor(s). The control system generates the stepped capacities of the refrigeration system by configuring and controlling the operation of the compressors and the output capacity provided by the compressors.

Abstract: A reciprocating compressor having a linear motor, at least one piston and cylinder arrangement and a mechanism operatively connecting the linear motor to the piston and cylinder arrangement is provided. The piston and cylinder arrangement operate to compress a fluid, preferably a refrigerant gas. The piston and cylinder arrangement has a cylinder, a piston configured and disposed to travel in the cylinder and a piston rod connected to the piston. The mechanism connects the linear motor to the piston rod to move the piston in the cylinder upon operation of the linear motor. The mechanism is configured and disposed to limit overtravel of the piston in the cylinder in response to a light load of the reciprocating compressor and to limit undertravel of the piston in the cylinder in response to a heavy load in the reciprocating compressor.

Abstract: A compression device for use in a HVAC&R system that includes a compressor for compressing vaporized refrigerant having a compressor inlet and compressor outlet for directing compressed refrigerant downstream along a first conduit to a condenser. An accumulator is provided for preventing liquid refrigerant from reaching the compressor. The accumulator has an accumulator inlet for receiving refrigerant along a second conduit from an upstream evaporator and an accumulator outlet in fluid communication with the compressor inlet for receiving vaporized refrigerant therein. The accumulator and compressor are integrally connected thereto so that the accumulator and compressor may be installed into a refrigerant recycling system by connecting the compressor outlet with the first conduit and connecting the accumulator inlet with the second conduit. A desiccant is disposed inside the accumulator between the accumulator inlet and outlet for removing moisture from the refrigerant.

Abstract: A crankshaft having at least two eccentric members of different diameter and a method of assembling a reciprocating compressor using a crankshaft having at least two eccentric members of different diameter are provided. A crankshaft having two eccentric members of different diameter is provided for more easily assembling a four-cylinder reciprocating compressor. The eccentric member having a smaller diameter is more easily inserted through apertures of connecting rods having a larger diameter than the eccentric member.

Abstract: A compressor for providing automatic capacity modulation is disclosed. The compressor comprises a compression chamber, a compressing member, a reexpansion area, a flow passage, a valve member, and a biasing member. The flow passage is in fluid communication with the compression chamber and the reexpansion area. In one position, the valve member permits flow through the flow passage and in a second position it prevents flow. The valve member is subjected to a first operating condition of fluid on one side and a second operating condition of the fluid on the other side. The biasing member exerts a biasing force on the valve member. When the first operating condition reaches a predetermined point relative to the second operating condition, the valve member moves and effects a change in the capacity of the compressor.

Abstract: A rotary compressor having a housing with a motor and an internal accumulator located on the low pressure side and an oil sump located on the high pressure side. A sealing means positioned within the housing defines a first chamber and a second chamber. The sealing means substantially maintains the pressure differential between the chambers by segregating high pressure fluid in the second chamber from low pressure fluid in the first chamber. The fluid entering the housing is separated into a gas portion and a liquid portion, the liquid portion being directed downward toward the motor to provide cooling for the motor while the gas portion is directed to a compressor portion. The liquid portion collects about the motor above the sealing means. An orifice or aperture through the sealing means allows liquid collected above the sealing means to be reintroduced into the compressor suction inlet and metered into the refrigerant gas in a controlled fashion and resupply the sump with lubricant.

Abstract: A system and method for controlling a variable capacity compressor driven by a motor. Preferably, said system and method are used with a reversible, two-stage compressor motor. In one embodiment, the method includes, for example, operating the variable capacity compressor at a first capacity to satisfy a demand for heating or cooling; detecting a change in the demand for heating or cooling; operating the variable capacity compressor at a second, different capacity based on the detected change in demand; detecting an operating parameter that can indicate an opportunity to increase compressor efficiency when the compressor is operating at a given capacity; and varying the torque applied by the motor when the detected operating parameter indicates an opportunity to increase efficiency of the compressor by varying the torque.

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 crankshaft having at least two eccentric members of different diameter and a method of assembling a reciprocating compressor using a crankshaft having at least two eccentric members of different diameter are provided. A crankshaft having two eccentric members of different diameter is provided for more easily assembling a four-cylinder reciprocating compressor. The eccentric member having a smaller diameter is more easily inserted through apertures of connecting rods having a larger diameter than the eccentric member.

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 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.

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.

Abstract: A shaft load balancing system includes a housing divided into a first chamber at a first operating pressure and a second chamber at a second, lower operating pressure. A shaft passes from the first chamber into the second chamber. The shaft includes a first end in the first chamber, a second end in the second chamber, and a substantially axial channel connecting the first end and the second end. The first end is in fluid communication with a fluid reservoir in the housing. A reaction member engages the second end. The reaction member includes a compression volume in fluid communication with the channel. A pressure differential between the chambers forces fluid from the fluid reservoir through the channel and into the compression volume. The reaction member transmits the fluid force to the housing, allowing the fluid to create a force on the second end of the shaft.

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 re-expansion chamber.

Abstract: A compressor system includes a housing with a low pressure first chamber and a high pressure second chamber. A motor in the first chamber has a shaft that passes into the second chamber. A compressor in the housing is operably connected to the motor by the shaft. The second chamber contains an oil sump storing lubricating oil for the compressor. A fluid path through the compressor system includes a first orifice in the housing communicating a suction tube with the first chamber, a first fluid passage communicating the first chamber with the compressor suction port, a second fluid passage communicating the compressor discharge port with the second chamber, and a second orifice in the housing communicating the second chamber with a discharge tube. By the action of the compressor, the fluid in the first chamber is maintained at compressor suction pressure and the fluid in the second chamber is maintained at compressor discharge pressure.