Abstract: A reciprocating compressor may include a shell, a first cylinder, a plate, a second cylinder, and a piston. The first cylinder may be disposed within the shell and may include a first valve. The plate may be fixed relative to the first cylinder and may include a second valve. The second cylinder may be axially aligned with the first cylinder and may be moveable relative to the first cylinder between first and second positions. The piston may be disposed within the second cylinder and may include a third valve. The piston may reciprocate relative to the first and second cylinders. The piston and the plate may define a first compression chamber therebetween. The piston and the first cylinder may define a second compression chamber therebetween. A fluid-injection passage extending through the first cylinder selectively provides a working fluid from a source to the second compression chamber.

Abstract: A system and method are provided including a system controller for a refrigeration or HVAC system having a compressor rack with a compressor and a condensing unit with a condenser fan. The system controller monitors and controls operation of the refrigeration or HVAC system. A rack controller monitors and controls operation of the compressor rack and determines compressor rack power consumption data. A condensing unit controller monitors and controls operation of the condensing unit and determines condensing unit power consumption data. The system controller receives the compressor rack power consumption data and the condensing unit power consumption data, determines a total power consumption of the refrigeration or HVAC system, determines a predicted power consumption or a benchmark power consumption for the refrigeration system, compares the total power consumption with the predicted power consumption or the benchmark power consumption, and generates an alert based on the comparison.

Abstract: A system and a method are provided including a system controller for a refrigeration or HVAC system having a compressor rack with a compressor and a condensing unit with a condenser fan. The system controller monitors and controls operation of the refrigeration or HVAC system. A rack controller monitors and controls operation of the compressor rack. The system controller determines a flood-back discharge temperature corresponding to a flood-back condition, receives an actual discharge temperature associated with the compressor rack, compares the actual discharge temperature with the flood-back discharge temperature, and generates a notification to the rack controller based on the comparison.

Abstract: A refrigerant compressor includes an electric motor. A current sensor measures current flow to the electric motor. A switching device is configured to close and open to allow and prevent current flow to the electric motor, respectively. A maximum continuous current (MCC) device includes a stored digital value corresponding to a maximum continuous current for the electric motor. A motor protection module: communicates with the MCC device, the current sensor, and the switching device; determines a first MCC for the electric motor as a function of the stored digital value received from the MCC device; selectively sets a predetermined MCC to the first MCC; and controls the switching device based on a comparison of the current flow to the electric motor and the predetermined MCC.

Abstract: A reciprocating compressor may include a shell, a first cylinder, a plate, a second cylinder, and a piston. The first cylinder may be disposed within the shell and may include a first valve. The plate may be fixed relative to the first cylinder and may include a second valve. The second cylinder may be axially aligned with the first cylinder and may be moveable relative to the first cylinder between first and second positions. The piston may be disposed within the second cylinder and may include a third valve. The piston may reciprocate relative to the first and second cylinders. The piston and the plate may define a first compression chamber therebetween. The piston and the first cylinder may define a second compression chamber therebetween.

Abstract: A compressor may include a compression cylinder, a compression piston, a crankshaft, an injection bore, a position sensor, and a valve assembly. The compression piston is disposed within the compression cylinder and is operable to compress a vapor disposed within the compression cylinder from a suction pressure to a discharge pressure. The crankshaft is operable to cycle the compression piston within the compression cylinder. The injection bore may be in fluid communication with the compression cylinder and may be operable to selectively communicate intermediate-pressure vapor at a pressure between the suction pressure and said discharge pressure to the compression cylinder. The position sensor may measure a rotational position of the crankshaft. The valve assembly may be associated with the injection bore. The valve assembly may be operable to control passage of fluid from the injection bore into the compression cylinder in response to data provided by the position sensor.

Abstract: A refrigerant compressor includes an electric motor. A current sensor measures current flow to the electric motor. A switching device is configured to close and open to allow and prevent current flow to the electric motor, respectively. A maximum continuous current (MCC) device includes a stored digital value corresponding to a maximum continuous current for the electric motor. A motor protection module: communicates with the MCC device, the current sensor, and the switching device; determines a first MCC for the electric motor as a function of the stored digital value received from the MCC device; selectively sets a predetermined MCC to the first MCC; and controls the switching device based on a comparison of the current flow to the electric motor and the predetermined MCC.

Abstract: A system includes a refrigerant compressor including an electric motor, a current sensor that measures current flow to the electric motor, a switching device configured to close and open to allow and prevent current flow to the electric motor, respectively, a maximum continuous current (MCC) device that includes a resistance corresponding to a maximum continuous current for the electric motor, and a motor protection module. The motor protection module communicates with the MCC device, the current sensor, and the switching device and determines a first MCC value for the electric motor as a function of the resistance of the MCC device. The motor protection module also selectively sets a predetermined MCC to the first MCC and controls the switching device based on a comparison of the current flow to the electric motor and the predetermined MCC.

Abstract: A reciprocating compressor may include a shell, a first cylinder, a plate, a second cylinder, and a piston. The first cylinder may be disposed within the shell and may include a first valve. The plate may be fixed relative to the first cylinder and may include a second valve. The second cylinder may be axially aligned with the first cylinder and may be moveable relative to the first cylinder between first and second positions. The piston may be disposed within the second cylinder and may include a third valve. The piston may reciprocate relative to the first and second cylinders. The piston and the plate may define a first compression chamber therebetween. The piston and the first cylinder may define a second compression chamber therebetween.

Abstract: A compressor is provided and may include a first compression mechanism, a first valve plate including a first port, and a first manifold including a first cylinder having a first piston disposed therein. The first piston may be movable between a first position opening the first port and a second position closing the first port. The compressor may additionally include a second compression mechanism, a second valve plate including a second port, and a second manifold including a second cylinder having a second piston disposed therein. The second piston may be movable between a first position opening the second port and a second position closing the second port. A valve assembly may move one of the first and second pistons into the first position while maintaining the other of the first and second pistons in the second position.

Abstract: An apparatus is provided and may include a control valve that moves a pressure-responsive unloader valve between a first position permitting flow through a valve plate and into a compression mechanism and a second position restricting flow through the valve plate and into the compression mechanism. The control valve may include at least one pressure-responsive valve member movable between a first state supplying discharge-pressure gas to the unloader valve to urge the unloader valve into one of the first position and the second position and a second state venting the discharge-pressure gas from the unloader valve to move the unloader valve into the other of the first position and the second position.

Abstract: A compressor assembly is provided and may include a first compression cylinder, a first compression piston disposed within the first compression cylinder that compresses a vapor disposed within the first compression cylinder, and a crankshaft that cycles the first compression piston within the first compression cylinder. The compressor assembly may additionally include a first control piston moveable between a first state restricting passage of intermediate-pressure fluid into the first compression cylinder and a second state permitting passage of intermediate-pressure fluid into the first compression cylinder.

Abstract: A compressor assembly is provided and may include a compression cylinder and a compression piston disposed within the compression cylinder that compresses a vapor disposed within the compression cylinder from a suction pressure to a discharge pressure. The compressor assembly may additionally include a crankshaft that cycles the compression piston within the compression cylinder and an injection port in fluid communication with the compression cylinder that selectively communicates intermediate-pressure vapor at a pressure between the suction pressure vapor and the discharge pressure vapor to the compression cylinder. The injection port may communicate the intermediate-pressure vapor to the compression cylinder when the compression piston exposes the injection port and may be prevented from communicating the intermediate-pressure vapor to the compression cylinder when the compression piston blocks the injection port.

Abstract: An apparatus is provided and may include a compression mechanism, a valve plate having a plurality of ports, a header, and a plurality of cylinders disposed within the header. A plurality of pistons may be respectively disposed in the plurality of cylinders and may be movable between a first position separated from the valve plate and permitting flow through the plurality of ports and into the compression mechanism and a second position engaging the valve plate and restricting flow through the plurality of ports and into the compression mechanism. A chamber may be disposed within each of the cylinders and may receive a pressurized fluid in a first mode to move the piston into the second position and may vent the pressurized fluid in a second mode to move the piston into the first position. One of the chambers may include a different diameter than the other of the chambers.

Abstract: An apparatus is provided and may include a compression mechanism, a valve plate including a plurality of ports in fluid communication with the compression mechanism, and a header disposed adjacent to the valve plate. A plurality of cylinders may be disposed within the header and a plurality of pistons may be respectively disposed in the plurality of cylinders and may be movable between a first position separated from the valve plate and a second position engaging the valve plate. A chamber may be disposed within each of the cylinders and may receive a pressurized fluid in a first mode to move the piston into the second position and may vent the pressurized fluid in a second mode to move the piston into the first position. One of the chambers may include a smaller volume than the other of the chambers.

Abstract: An apparatus is provided and may include a control valve that moves a pressure-responsive unloader valve between a first position permitting flow through a valve plate and into a compression mechanism and a second position restricting flow through the valve plate and into the compression mechanism. The control valve may include at least one pressure-responsive valve member movable between a first state supplying discharge-pressure gas to the unloader valve to urge the unloader valve into one of the first position and the second position and a second state venting the discharge-pressure gas from the unloader valve to move the unloader valve into the other of the first position and the second position.

Abstract: An apparatus is provided and may include a compression mechanism, a valve plate associated with the compression mechanism and having at least one port in fluid communication with the compression mechanism, and a manifold disposed adjacent to the valve plate. A cylinder may be formed in the manifold and a piston may be disposed within the manifold and may be movable relative to the manifold between a first position separated from the valve plate and a second position engaging the valve plate. A valve element may be disposed within the piston and may be movable relative to the piston and the manifold. The valve element may be movable between an open position spaced apart from the valve plate and permitting flow through the port and into the compression mechanism and a closed position engaging the valve plate and restricting flow through the port and into the compression mechanism.

Abstract: An apparatus is provided and may include a compression mechanism, a valve plate including a plurality of ports in fluid communication with the compression mechanism, and a header disposed adjacent to the valve plate. A plurality of cylinders may be disposed within the header and a plurality of pistons may be respectively disposed in the plurality of cylinders and may be movable between a first position separated from the valve plate and a second position engaging the valve plate. A chamber may be disposed within each of the cylinders and may receive a pressurized fluid in a first mode to move the piston into the second position and may vent the pressurized fluid in a second mode to move the piston into the first position. One of the chambers may include a smaller volume than the other of the chambers.

Abstract: An apparatus is provided and may include a compression mechanism, a valve plate associated with the compression mechanism and having at least one port in fluid communication with the compression mechanism, and a manifold disposed adjacent to the valve plate. A cylinder may be formed in the manifold and a piston may be disposed within the manifold and may be movable relative to the manifold between a first position separated from the valve plate and a second position engaging the valve plate. A valve element may be disposed within the piston and may be movable relative to the piston and the manifold. The valve element may be movable between an open position spaced apart from the valve plate and permitting flow through the port and into the compression mechanism and a closed position engaging the valve plate and restricting flow through the port and into the compression mechanism.

Abstract: A reciprocating compressor is provided with a seal casing and includes a motor and a uni-body member which is mounted to the motor and provides a cylinder and head portion formed as a unitary member in order to reduce the number of machining operations and the number of parts required for assembly of the reciprocating compressor.