A scroll compressor is disclosed. The scroll compressor includes a compressor housing; an orbiting scroll member disposed within the housing; a non-orbiting scroll member disposed within the housing, wherein the orbiting scroll member and the non-orbiting scroll member are intermeshed thereby forming a compression chamber within the housing; and an endplate secured to the non-orbiting scroll member. The endplate includes a check valve surface configured to provide a stop for a check valve of the scroll compressor, a radial sealing surface configured to receive a radial seal, an unloading mechanism surface configured to provide a stop for an unloading mechanism, and a pressure chamber for controlling the unloading mechanism, the endplate also including an aperture that fluidly connects the compression chamber and a discharge chamber of the scroll compressor.

Systems and methods for scroll unloading detection are provided and include a scroll compressor having a scroll compression mechanism. A controller determines a predicted discharge temperature of the scroll compressor, receives an actual discharge temperature of the scroll compressor, and compares the predicted discharge temperature with the actual discharge temperature. The controller also compares a speed of the scroll compressor with a speed threshold and detects unloading of the scroll compression mechanism based on the comparison of the predicted discharge temperature with the actual discharge temperature and based on the comparison of the speed of the scroll compressor with the speed threshold. The controller performs at least one of generating an alert and a remediating action in response to detecting the unloading of the scroll compression mechanism.

The embodiments disclosed herein are directed to systems and methods to control a HVAC system based on a state of an unloader of a compressor of the HVAC system.

A refrigeration cycle device includes a compressor. The compressor includes a casing, a driving unit disposed in the casing, a compression unit coupled to the driving unit and configured to compress a refrigerant, and a valve configured to control a flow of the refrigerant in the casing. The valve includes a valve chamber including a main flow path in which the refrigerant is to flow, the main flow path including a refrigerant inlet and a refrigerant outlet. The valve also includes a floating body disposed in the valve chamber to open or close the main flow path, and a bypass flow path formed in the valve chamber and which is to be opened or closed by the floating body. When the driving unit is stopped and the bypass flow path is opened by the floating body, the refrigerant is to be detoured to the bypass flow path.

Methods and systems for controlling a chiller system to achieve control stability while maintaining optimum efficiency. Particularly, methods and systems for controlling a centrifugal compressor speed and an inlet guide vane position that establishes three distinct regions in the control path: (i) during initial unloading from full load, the inlet guide vane position is kept at a fully open position while the centrifugal compressor speed is changed to achieve the desired cooling capacity; (ii) between an inflection point and a transition point, keeping the centrifugal compressor speed constant while the inlet guide vane position is changed to achieve the desired cooling capacity; and (iii) between the transition point and zero cooling capacity, changing both the inlet guide vane position and the centrifugal compressor speed to achieve the desired cooling capacity.

A method of positioning an inlet guide vane assembly before start-up of a chiller system including a compressor, a condenser, and a cooler is provided including receiving a first input form sensors located in the cooler and the condenser. A saturation temperature is calculated based on the input from the sensors. A second input indicative of a minimum speed of a motor coupled to the compressor at start-up is received. Using the calculated saturation temperature and the second input, an allowable position of the inlet guide vane assembly is determined. The inlet guide vane assembly is then moved to the determined allowable position.

A compressor uses a refrigerant containing R1123 (1,1,2-trifluoroethylene) as a working fluid, and uses a polyvinyl ether oil as a compressor lubricating oil. In addition, a fixed scroll and a revolving scroll each having a spiral lap rising from an end plate, and a compression chamber which is formed by meshing the fixed scroll and the revolving scroll, are provided. In addition, a discharge hole which is provided at a center position of the end plate of the fixed scroll, and is open to a discharge chamber, a bypass hole which is provided in the end plate of the fixed scroll, and communicates with the compression chamber and the discharge chamber at a timing different from a timing at which the compression chamber communicates with the discharge hole, and a check valve which is provided in the bypass hole, and allows a flow from the compression chamber side to the discharge chamber side.

A compressor uses a refrigerant containing R1123 (1,1,2-trifluoroethylene) as a working fluid, and uses a polyol ester oil as a compressor lubricating oil. In addition, a fixed scroll and a revolving scroll each having a spiral lap rising from an end plate, and a compression chamber which is formed by meshing the fixed scroll and the revolving scroll, are provided. In addition, a discharge hole which is provided at a center position of the end plate of the fixed scroll, and is open to a discharge chamber, a bypass hole which is provided in the end plate of the fixed scroll, and communicates with the compression chamber and the discharge chamber at a timing different from a timing at which the compression chamber communicates with the discharge hole, and a check valve which is provided in the bypass hole, and allows a flow from the compression chamber side to the discharge chamber side.

The present invention describes a valve mechanism for refrigerating machines compressors. More specifically, the valve mechanism operates to allow the equalization of pressure between the compression chamber of a reciprocating compressor and the discharge volume of the same compressor. This equalization is aimed at reducing the torque required for departure. The present invention lies in the field of mechanical engineering, more specifically in the field of fluid and cooling mechanics.

A pressure relief arrangement in refrigerant circuits with one high-pressure side and one low-pressure side, which is characterized in that the high-pressure side is fluidically connected with the low-pressure side of the refrigerant circuit via an overpressure relief device, wherein the overpressure relief device causes pressure reduction of the overpressure in the case of overpressure on the high-pressure side and fluid flows from the high-pressure side to the low-pressure side of the refrigerant circuit.