A scroll type positive displacement assembly includes a first scroll and a second scroll, where the second scroll is configured to orbit with respect to a center of the first scroll without rotating with respect to the first scroll. Together, the first scroll and the second scroll define a compression chamber between two seal points where the first scroll and the second scroll contact one another as the second scroll orbits with respect to the first scroll during a compression cycle, and the two seal points come together proximate to a discharge port between the first scroll and the second scroll such that there is at least substantially no dead space between the first scroll and the second scroll at an end of the compression cycle. For example, the two seal points remain in sealing contact during at least one hundred and eighty (180) degrees of the compression cycle.

A scroll type positive displacement assembly includes a first scroll and a second scroll, where the second scroll is configured to orbit with respect to a center of the first scroll without rotating with respect to the first scroll. Together, the first scroll and the second scroll define a compression chamber between two seal points where the first scroll and the second scroll contact one another as the second scroll orbits with respect to the first scroll during a compression cycle, and the two seal points come together proximate to a discharge port between the first scroll and the second scroll such that there is at least substantially no dead space between the first scroll and the second scroll at an end of the compression cycle. For example, the two seal points remain in sealing contact during at least one hundred and eighty (180) degrees of the compression cycle.

A pumping system is provided, including a rough-vacuum pump; a Roots vacuum pump including a pumping stage having a stator inside which two Roots rotors are configured to rotate synchronously in opposite directions to drive a gas to be pumped between an inlet orifice and an outlet orifice; and a pipeline connecting the outlet orifice to an intake of the rough-vacuum pump, a shortest distance between an edge of the outlet orifice and each of the Roots rotors in the pumping stage being less than 3 cm, and the outlet orifice being situated at the end of an upstream tube of the pipeline that passes into the pumping stage.

A pumping system is provided, including a rough-vacuum pump; a Roots vacuum pump including a pumping stage having a stator inside which two Roots rotors are configured to rotate synchronously in opposite directions to drive a gas to be pumped between an inlet orifice and an outlet orifice; and a pipeline connecting the outlet orifice to an intake of the rough-vacuum pump, a shortest distance between an edge of the outlet orifice and each of the Roots rotors in the pumping stage being less than 3 cm, and the outlet orifice being situated at the end of an upstream tube of the pipeline that passes into the pumping stage.

A damping apparatus for an exhaust valve in a compressor, an exhaust valve assembly having the damping apparatus, and a compressor using the exhaust valve assembly. The damping apparatus comprises a fixed body; the fixed body comprises an exhaust hole comprises an exhaust hole through which a compression cavity and an exhaust cavity are in fluid communication with each other; the exhaust hole comprises an inlet, an outlet, and an intermediate cavity provided between the inlet and the outlet and allowing the inlet and the outlet to be in fluid communication with each other; the intermediate cavity is configured to enable the backflow of the gas from the exhaust cavity to form a vortex in the intermediate cavity. The damping apparatus has advantages of reducing the force and frequency of impacts on an exhaust valve plate, and prolonging the service life of the valve plate.

A damping apparatus for an exhaust valve in a compressor, an exhaust valve assembly having the damping apparatus, and a compressor using the exhaust valve assembly. The damping apparatus comprises a fixed body; the fixed body comprises an exhaust hole comprises an exhaust hole through which a compression cavity and an exhaust cavity are in fluid communication with each other; the exhaust hole comprises an inlet, an outlet, and an intermediate cavity provided between the inlet and the outlet and allowing the inlet and the outlet to be in fluid communication with each other; the intermediate cavity is configured to enable the backflow of the gas from the exhaust cavity to form a vortex in the intermediate cavity. The damping apparatus has advantages of reducing the force and frequency of impacts on an exhaust valve plate, and prolonging the service life of the valve plate.

A rotary compressor includes a cylinder having a vane slot and a compression chamber, a shaft having an eccentric portion and configured to perpendicularly pass through a center of the compression chamber, a roller having a coupling groove and configured to orbit in the compression chamber by rotation of the shaft, and a vane having a vane hinge coupled to the coupling groove and a vane body being inserted into the vane slot and configured to divide the compression chamber into a discharge space and a suction space. A shape of the discharge-sided groove close to the discharge space and a shape of the suction-sided groove close to the suction space are asymmetrically formed between the vane hinge and the vane body with respect to the a central axis of the vane.

A rotary compressor includes a cylinder having a vane slot and a compression chamber, a shaft having an eccentric portion and configured to perpendicularly pass through a center of the compression chamber, a roller having a coupling groove and configured to orbit in the compression chamber by rotation of the shaft, and a vane having a vane hinge coupled to the coupling groove and a vane body being inserted into the vane slot and configured to divide the compression chamber into a discharge space and a suction space. A shape of the discharge-sided groove close to the discharge space and a shape of the suction-sided groove close to the suction space are asymmetrically formed between the vane hinge and the vane body with respect to the a central axis of the vane.

A horizontal compressor includes a case; a high and low pressure separating plate dividing an inner space of the case into a high-pressure chamber and a low-pressure chamber; a compressor in the high-pressure chamber configured to be operated by a motor to compress refrigerant; a suction pipe in the case to communicate with the low-pressure chamber and through which the refrigerant is sucked; and an internal suction pipe to pass through the high and low pressure separating plate, one end of the internal suction pipe connected to the compressor and another end of the internal suction pipe to communicate with the low-pressure chamber so that the refrigerant in the low-pressure chamber flows into the compressor, wherein the internal suction pipe includes a connecting pipe adjacent to a lower surface of the case parallel to a central axis of the case.

A horizontal compressor includes a case; a high and low pressure separating plate dividing an inner space of the case into a high-pressure chamber and a low-pressure chamber; a compressor in the high-pressure chamber configured to be operated by a motor to compress refrigerant; a suction pipe in the case to communicate with the low-pressure chamber and through which the refrigerant is sucked; and an internal suction pipe to pass through the high and low pressure separating plate, one end of the internal suction pipe connected to the compressor and another end of the internal suction pipe to communicate with the low-pressure chamber so that the refrigerant in the low-pressure chamber flows into the compressor, wherein the internal suction pipe includes a connecting pipe adjacent to a lower surface of the case parallel to a central axis of the case.