Abstract: A centrifugal compressor includes a first stage and a second stage. At least one of the first stage and the second stage includes an impeller and a shroud spaced from the impeller and configured to guide a fluid flow through the impeller. The shroud is selectively moveable between an engaged position and a disengaged position.

Abstract: This disclosure relates to a compressor having a partially hollow shaft. In particular, an exemplary compressor includes a shaft which is partially hollow, and at least one impeller rotatably coupled to the shaft. The compressor may be a refrigerant compressor used in a heating, ventilation, and air conditioning (HVAC) chiller system.

Abstract: This disclosure relates to a compressor having a partially hollow shaft. In particular, an exemplary compressor includes a shaft which is partially hollow, and at least one impeller rotatably coupled to the shaft. The compressor may be a refrigerant compressor used in a heating, ventilation, and air conditioning (HVAC) chiller system.

Abstract: A centrifugal compressor includes a first stage and a second stage. At least one of the first stage and the second stage includes an impeller and a shroud spaced from the impeller and configured to guide a fluid flow through the impeller. The shroud is selectively moveable between an engaged position and a disengaged position.

Abstract: A scroll compressor and a sealing method and sealing arrangement for a mid-pressure chamber thereof are provided. The scroll compressor includes: a scroll compressor shell; a housing, mounted inside the scroll compressor shell; a fixed scroll, fixed onto the housing; an orbiting scroll, supported on the housing and cooperating with the fixed scroll; a driving mechanism, located between the orbiting scroll and the housing and connected to the orbiting scroll to drive the orbiting scroll to orbit; and a mid-pressure chamber, which is a cavity surrounded by a hub of the orbiting scroll and a part of the housing and which is sealed by two sealing members.

Abstract: A sealed compressor has an electric motor driving a compressor pump unit, and a shell enclosing the electric motor and compressor pump unit. An electrical connector with the shell supplies electrical power to the motor. A terminal housing is mounted to an outer surface of the shell, and a terminal plug is received within the terminal housing. The terminal plug has electric connections to connect into the electric connector within the shell. The housing includes a cover plate enclosing a chamber for the housing and which receives the terminal plug. A spring extends from the terminal plug, and reacts against a surface of the cover to bias the terminal plug to maintain the electric connection between the terminal plug and the electrical connector in the shell.

Abstract: A sealed compressor has an electric motor driving a compressor pump unit, and a shell enclosing the electric motor and compressor pump unit. An electrical connector with the shell supplies electrical power to the motor. A terminal housing is mounted to an outer surface of the shell, and a terminal plug is received within the terminal housing. The terminal plug has electric connections to connect into the electric connector within the shell. The housing includes a cover plate enclosing a chamber for the housing and which receives the terminal plug. A spring extends from the terminal plug, and reacts against a surface of the cover to bias the terminal plug to maintain the electric connection between the terminal plug and the electrical connector in the shell.

Abstract: A valve for selectively allowing the return of oil from a discharge plenum to a suction plenum includes a passage which is selectively opened or blocked by a valve spool. The valve spool sees a pressure from a discharge pressure location upstream of a discharge check valve on one face, and a discharge pressure from a discharge plenum on an opposed face. While the compressor is running, the two pressures should be relatively equal. The face which sees the pressure from the chamber upstream of the check valve is larger than the face which sees the pressure from the discharge plenum. Thus, when the compressor is running, the valve spool is biased to a first position at which it allows oil return from the discharge plenum to the suction plenum. However, upon shutdown of the compressor, the pressure in the chamber upstream of the discharge valve drops. The valve spool will be driven to a second position at which it blocks communication for oil return.

Abstract: A scroll compressor comprises a first scroll member having a generally spiral wrap and a second scroll member having a generally spiral wrap. The generally spiral wraps interfit to define compression chambers. A pair of ports leads from the compression chambers. A pair of valves selectively blocks flow of refrigerant from the ports leaving the compression chambers. The valves selectively control the flow such that flow may pass from neither of the two ports, from both of the two ports, or from only one of the two ports to provide three levels of capacity control.

Abstract: A scroll compressor is provided with an oil return tube having an outlet for directing oil toward a motor protector for an electric motor. The oil supply tube is positioned to be at an angle relative to the drive axis of a shaft driven by the electric motor. This ensures that the outlet of the oil supply tube can be properly positioned relative to the electric motor. Under normal conditions, an adequate flow of refrigerant will pull the oil from the oil supply tube and away from the motor protector. However, should there be an inadequate flow of refrigerant within the sealed compressor, the oil will contact the motor protector, which in turn may stop operation of the electric motor.

Abstract: A scroll compressor includes a scroll member having a base and a generally spiral wrap that extends from the base to define a portion of a compression chamber. The scroll member is made of a cast iron material comprising a microstructure having graphite nodules.

Abstract: A spacer is positioned between an outer periphery of a motor stator, and the inner periphery of a center shell for a sealed compressor. The spacer allows a relatively small diameter motor to be used in a relatively large diameter center shell. The spacer includes a bearing mount in a lower plate, and a plurality of axially extending fingers positioned between the stator and the center shell. The spacer also includes a stop for proper positioning of the stator within the center shell.

Abstract: A self-modulating scroll compressor includes a built-in volume ratio that is defined as the ratio of a volume of a compression pocket just after completion of suction, i.e. at a beginning of a compression cycle, to the volume of the compression pocket just prior to discharge, i.e. at the end of the compression cycle. The built-in volume ratio can be controlled by the geometry of the scrolls and can be modified by, for example, extending the wrap or adding more turns to the wrap. Because the built-in volume ratio decreases to an effective volume ratio at lower capacity operation, the built-in volume ratio is at least 2.4 in order to optimize overall compressor efficiency.

Abstract: A scroll compressor has a reed valve mounted on a central discharge port. The reed valve has a valve portion at a first end and a pin holding the reed valve onto a non-orbiting scroll member at a second end. The reed valve extends along a plane which is non-perpendicular to a drive axis of a drive shaft such that the second end, which receives the pin, is further removed from the compression chambers than is the first end of the reed valve, which covers the central discharge port.

Abstract: A scroll compressor is provided having appropriate clearance for movement of the orbiting scroll member. Clearance is provided without requiring contact between the crankcase, which supports the orbiting scroll, and the non-orbiting scroll member. Clearance is established during the assembly process using installation tooling that establishes locations of components using a reference point. Clearance is also established using spacers.

Abstract: A valve for selectively allowing the return of oil from a discharge plenum to a suction plenum includes a passage which is selectively opened or blocked by a valve spool. The valve spool sees a pressure from a discharge pressure location upstream of a discharge check valve on one face, and a discharge pressure from a discharge plenum on an opposed face. While the compressor is running, the two pressures should be relatively equal. The face which sees the pressure from the chamber upstream of the check valve is larger than the face which sees the pressure from the discharge plenum. Thus, when the compressor is running, the valve spool is biased to a first position at which it allows oil return from the discharge plenum to the suction plenum. However, upon shutdown of the compressor, the pressure in the chamber upstream of the discharge valve drops. The valve spool will be driven to a second position at which it blocks communication for oil return.

Abstract: A compressor is provided with a dimple and a lower end cap to receive a positioning fixture pin to position the lower end cap prior to a welding operation. The use of the dimple ensures the lower end cap is properly positioned when welding occurs. In the past, lower end caps have often been mis-aligned when welded to the center shell. Further, the dimple provides the dual function of positioning a magnet within the compressor housing.

Abstract: A scroll compressor comprises a first scroll member having a generally spiral wrap and a second scroll member having a generally spiral wrap. The generally spiral wraps interfit to define compression chambers. A pair of ports leads from the compression chambers. A pair of valves selectively blocks flow of refrigerant from the ports leaving the compression chambers. The valves selectively control the flow such that flow may pass from neither of the two ports, from both of the two ports, or from only one of the two ports to provide three levels of capacity control.

Abstract: A scroll compressor has a reed valve mounted on a central discharge port. The reed valve has a valve portion at a first end and a pin holding the reed valve onto a non-orbiting scroll member at a second end. The reed valve extends along a plane which is non-perpendicular to a drive axis of a drive shaft such that the second end, which receives the pin, is further removed from the compression chambers than is the first end of the reed valve, which covers the central discharge port.

Abstract: A scroll compressor has a stepped wrap such that there is a greater height outer portion and a lesser height more central portion. Bypass ports are associated with the transition zone between the higher and lesser height portions. By providing the bypass port in a stepped scroll compressor, greater reductions in capacity can be achieved than have been provided in the prior art.