A shunt-enhanced decompression and pulsation trap (SEDAPT) for a screw compressor assists internal compression (IC), reduces gas pulsation and NVH (Noise, Vibration & Harshness), and improves off-design efficiency, without using a slide valve and/or a serial pulsation dampener. The SEDAPT includes an inner casing, e.g., an integral part of the compressor chamber, and an outer casing, e.g., surrounding part of the inner casing near the compressor discharge port, forming at least one diffusing chamber with an outflow orifice or nozzle equipped with an ODV (one-direction valve) at the outflow exit and a feedback region that provides a feedback outflow loop between the compressor chamber and the compressor discharge port. The SEDAPT automatically bleeds or compensates cavity pressure to meet different outlet pressures, eliminates or reduces energy waste, gas pulsations and NVH associated with any over-compression and under-compression before the discharge port opens.

A lower end plate includes: bolt holes through which bolts penetrate; a lower discharge valve; a lower discharge-valve accommodating recessed portion into which the lower discharge valve is accommodated; and a lower discharge-chamber recessed portion. A lower end plate cover is provided with a bulging portion. A lower end-plate cover chamber is formed by the lower discharge-valve accommodating recessed portion, the lower discharge-chamber recessed portion, and the bulging portion. Refrigerant passage holes include main refrigerant passage holes provided on the lower discharge-chamber recessed portion, and sub-refrigerant passage holes provided between the bolt hole and the lower discharge-valve accommodating recessed portion away from the lower discharge-valve accommodating recessed portion. The bulging portion is, in a cross section orthogonal to a rotating shaft, formed so as to overlap with at least a part of each of the main refrigerant passage holes and the sub-refrigerant passage holes.

A variable capacity compressor is provided, including: two cylinders and a middle plate; at least one flow channel provided in the middle plate, wherein one end of the flow channel is connected to an exhaust chamber of any one of the two cylinders, the other end is connected to a suction chamber of the other one of the two cylinders. In present disclosure, by setting a flow channel in the middle plate of the variable capacity compressor, the exhaust chamber of one cylinder is connected to the suction chamber of the other cylinder. When the flow channel is completely closed, the two cylinders operate independently; when the flow channel is opened, the refrigerant in the exhaust chamber flows into the suction chamber through the flow channel, that is, the upper cylinders and the lower cylinder are connected to each other, which can adjust the capacity of the compressor.

A rotary compressor may include a case, a cylinder, a roller, a vane, a main bearing and a sub bearing, and a discharge passage defined in the main bearing or the sub bearing to discharge refrigerant compressed in a compression space. The discharge passage may include at least one discharge hole formed through the main bearing or the sub bearing, and at least one discharge guide groove having a first end that communicates with the at least one discharge hole and a second end that extends from the at least one discharge hole toward a contact point between the cylinder and the roller and is recessed from one surface of the main bearing or the sub bearing forming the compression space. Accordingly, an amount of refrigerant remaining in the compression space even after a discharge stroke may be reduced.

A scroll compressor may include a first scroll and a second scroll orbiting relative to the first scroll to form compression chambers, a discharge port provided in the first scroll to discharge refrigerant compressed in the compression chamber, a discharge passage formed through the first discharged through the discharge to an upper side of the frame, and a discharge cover coupled to the first scroll and having a space to accommodate end portions of the discharge port and the discharge passage to guide the refrigerant discharged through the discharge port to the discharge passage. A volume of a discharge space defined in the space by the first scroll may be 4.5 or more, obtained by dividing a volume of the discharge space by a total volume of an initial compression chamber among the compression chambers.

A shunt-enhanced compression and pulsation trap (SECAPT) for a screw compressor assists internal compression (IC), reduces gas pulsation and NVH, and improves off-design efficiency, without using a slide valve and/or a serial pulsation dampener. The SECAPT includes an inner casing (e.g., an integral part of the compressor chamber) and an outer casing (e.g., surrounding part of the inner casing near the compressor discharge port) forming at least one diffusing chamber with a nozzle and a feedback region that provides a feedback flow loop between the compressor chamber and the compressor discharge port. The SECAPT automatically compensates cavity pressure to meet different outlet pressures (hence eliminating under-compression and/or over-compression when the discharge port opens), partially recovers potential energy associated with the under-compression (UC), and traps and attenuates gas pulsations and noise before the discharge port opens.

A coupling assembly arranged between an input shaft and a rotor shaft of a supercharger includes a first hub, a second hub, a first side coupling assembly, a second side coupling assembly, a central hub and a plurality of coupler pins. The first hub is mounted for concurrent rotation with the input shaft. The second hub is mounted for concurrent rotation with the rotor shaft. The first side coupling assembly has a first side coupling body and a first side elastomeric insert. The first side coupling body includes an inboard body portion having a first series of pockets and an outboard body portion having a second series of pockets. The first side elastomeric insert has a first and second plurality of lobes. The pockets of the first and second series of pockets are tangentially offset relative to each other and each receive respective first and second plurality of lobes therein.

The invention is related to a pulsation muffler (100) for a gaseous medium flow (107), which is supplied by a compressor. The pulsation muffler (100) comprises a housing (101) extending along a central axis with a medium flow inlet (106) and a medium flow outlet; several tubular absorber elements (108) concentrically arranged in the housing (10) and fluidically arranged one behind the other. Each tubular absorber element (108) is provided with an inlet area and an outlet area, positioned at an axial distance from each other. Between the respective radially adjacent wall sections of different absorber elements (108), a flow compartment (112, 114) is maintained for the medium flow (107).

In a rotary compressor, a lower end plate includes a lower discharge valve that opens and closes a lower discharge hole, a lower discharge-valve accommodating recessed portion in which the lower discharge valve is accommodated, and a lower discharge-chamber recessed portion that is formed so as to overlap with the lower discharge hole side of the lower discharge-valve accommodating recessed portion and communicates with a refrigerant passage hole. A lower end plate cover is formed in a flat-plate shape and is provided with a bulging portion having a portion facing the lower discharge hole. An upper end-plate cover chamber is formed by the lower discharge-valve accommodating recessed portion, the lower discharge-chamber recessed portion, and the bulging portion. The bulging portion has a volume of 1/18 or greater and 1/9 or less of a total of air volumes of an upper compression chamber and a lower compression chamber.

A silencer for vacuum pumps which allows only for unidirectional flow and which reduces the noises caused by the air discharged at the exhaust of said pump. The silencer features baffles to divert and disrupt the flow and an umbrella check valve to ensure the unidirectionality of the discharge flow.