A cylinder coupling structure of a compact air compressor includes a block, a tubular-shaped cylinder assembled to the block, a valve cover which covers the valve assembly, and at least one pressurized bolt which assembles the valve cover and the block. A piston is reciprocated inside the cylinder. A stator is assembled to the block, a rotator is located to relatively rotate as to the stator, and a crank axis is assembled to the rotator to integrally rotate with the rotator to be axially supported in the block and to be rotatable. A connecting rod, each of both ends thereof is connected to the crank axis and the piston, respectively.

A cylinder coupling structure of a compact air compressor includes a block, a tubular-shaped cylinder assembled to the block, a valve cover which covers the valve assembly, and at least one pressurized bolt which assembles the valve cover and the block. A piston is reciprocated inside the cylinder. A stator is assembled to the block, a rotator is located to relatively rotate as to the stator, and a crank axis is assembled to the rotator to integrally rotate with the rotator to be axially supported in the block and to be rotatable. A connecting rod, each of both ends thereof is connected to the crank axis and the piston, respectively.

A piston assembly for a piston pump includes an actuator rod, a piston coupled to the actuator rod and configured to contact a radially-inner wall of a cylinder, and an piston support structure coupled to the actuator rod and configured to contact the radially-inner wall of the cylinder. A fluid channel extends through the actuator rod and the piston support structure, and the fluid channel is configured to deliver a lubricating fluid to an annular space positioned between the piston and the piston support structure along an axial axis of the piston assembly.

A compressor includes a motor, a balance weight and a partition. The motor includes a rotor having a first end surface and a second end surface. The balance weight is disposed on the first end surface or the second end surface. The partition is disposed on the first end surface or the second end surface. The rotor has a through hole extending from the first end surface to the second end surface. The partition divides, from the through hole, at least one of a front region and a rear region. The front region is located in front of a front edge of the balance weight in a rotational direction of the rotor. The rear region is located behind a rear edge of the balance weight in the rotational direction of the rotor.

A valve for a reciprocating pump includes a housing, a first chamber, a second chamber, a first valve element, and a second valve element. The housing includes an inlet and an outlet. The first and second chambers are within the housing. The first chamber includes a first valve seat and is fluidly connected to the inlet. The second chamber includes a second valve seat and is fluidly connected to the outlet. The first valve element is disposed in the first chamber and includes a spring-loaded check valve element. The second valve element is disposed in the second chamber and includes a buoyant material.

The present application provides new and innovative high-pressure fluid systems for preventing seal burning due to gas auto-ignition. The provided systems include an o-ring disposed within a seal cavity of a cup seal to decrease the dead volume in the seal cavity. By reducing the dead volume, the o-ring decreases the volume of gas that is able to accumulate and thus helps prevent the gas from auto-igniting as the gas is compressed. By preventing the gas from auto-igniting, the provided system helps prevent seal burning, which helps prevent premature cup seal failure and prevent fluid contamination.

A compressor device for compressing a gas in at least one compression chamber in at least one compression cylinder is disclosed. In each of at least two drive cylinders, at least one drive piston is disposed, said at least one drive piston dividing each of the at least two drive cylinders into two drive chambers. The at least one first and second drive chamber, by way of a hydraulic fluid, are able to be periodically impinged with a fluid pressure in order for the respective drive piston to be moved. Each of the remaining drive chambers in the at least two drive cylinders, by way of a connection piece, are connected in a non-positive locking manner by a fluid. The movement of the drive pistons by way of at least one mechanical connection means is able to be transmitted to at least one compression piston.

A centrifugal-separation type oil separator includes a cylindrical separator body, and an inflow pipe arranged to introduce a fluid including an oil into the separator body. The inflow pipe includes a curved portion. A peripheral wall of the separator body and the inflow pipe include a common portion common to each other.

A valve for a reciprocating pump includes a housing, a first chamber, a second chamber, a first valve element, and a second valve element. The housing includes an inlet and an outlet. The first and second chambers are within the housing. The first chamber includes a first valve seat and is fluidly connected to the inlet. The second chamber includes a second valve seat and is fluidly connected to the outlet. The first valve element is disposed in the first chamber and includes a spring-loaded check valve element. The second valve element is disposed in the second chamber and includes a buoyant material.

A compressor includes a driving motor, a centrifugation space, a discharge pipe, a rotary shaft, a compression portion, a pump assembly, and an oil pickup. The centrifugation space is defined inside a case by a downstream side of the driving motor and the case, and enables centrifugation of a compressed refrigerant and a lubricant oil. The discharge pipe can discharge the refrigerant from the centrifugation space outside the case. The rotary shaft is coupled to a rotor of the driving motor and defines an oil supply path. The compression portion is provided at an upstream side of the driving motor and can compress the refrigerant as the rotary shaft rotates. The pump assembly is provided below the rotary shaft and can pump oil as rotated with the rotary shaft. The oil pickup defines an oil supply path between the pump assembly and a low oil space formed inside the case.