The disclosure discloses a method and a device for controlling cylinder switching of a compressor, a unit and an air conditioning system. The method includes: determining whether the compressor needs to perform cylinder switching; if so, adjusting current operating frequency according to a system pressure difference so that both the adjusted operating frequency and the system pressure difference meet a cylinder switching condition of the compressor; and controlling the compressor to perform cylinder switching. At the moment, the system pressure difference and the operation frequency are stable, and would not interfere the compressor's maintaining of the single-cylinder or double-cylinder operation state, which guarantees the energy efficiency of the unit where the compressor is located, and improves the use experience of a user.

Disclosed are a compressor control method, control apparatus and control system. The method include: receiving a cylinder switching instruction, and detecting operating parameters of a compressor; determining whether a cylinder switching operation is completed according to the operating parameters of the compressor; and after it is determined that the cylinder switching operation is completed, performing torque compensation.

A hydraulically operated compressor has a fixed piston and a fixed compression or outer cylinder. A drive or intermediate cylinder is located between the piston and outer cylinder. A compression chamber is formed between the drive cylinder and the outer cylinder. Drive fluid is pumped into and released from an interior chamber in the drive cylinder to reciprocate the drive cylinder. The drive fluid also provides cooling to the interior of the compressor.

A hermetic compressor may include a crankshaft having an input shaft rotatably supported on the cast-iron block along the crankshaft axis and connected to the electric motor rotary output, and an eccentric crankpin orbitally rotating about the axis as the crankshaft is rotated. A pair of opposed pistons may lie on the common plane. Each piston may be pivotably connected to one of the connecting rod piston ends to drive the pistons in an oscillatory manner within the cylinders as the crankshaft rotates. The piston and cylinder pairs may cause fluid to be pumped from the inlet port to the outlet port as the piston oscillates varying the volume of the enclosed space bound by the piston and the cylinder pairs.

A three-stage compression air pump includes a pump head and a pumping device. The pumping device includes first and second cylinders and a plunger. The first cylinder is connected with the pump head and coupled to a first piston moving in the second cylinder. The second cylinder includes a first end cap and a second end cap respectively coupled to the two ends thereof The first cylinder is inserted through the first end cap. The second end cap defines an orifice allowing outside air to flow into the second cylinder and includes a one-way valve preventing the air in the second cylinder from flowing outside the three-stage compression pump. The plunger is inserted in and movably coupled to the first cylinder and coupled to a second piston moving in the first cylinder and connected with the second end cap. The plunger is inserted through the first piston.

The present disclosure provides a control method of a compressor and a refrigerant circulation system. The control method includes deciding whether a current working volume state of the compressor is matched with a control instruction after the compressor completes a change to a working volume according to the control instruction; determining that the compressor operates normally in a case where the current working volume state of the compressor is matched with the control instruction; and determining that the compressor operates in fault in a case where the current working volume state of the compressor is not matched with the control instruction.

Systems and methods for enhancing performance in a reciprocating compressor are described. The compressor includes a cylinder, a crank shaft housing, a crank shaft, a motor, a motor housing and rod assembly. The rod assembly includes a coupling rod portion, a head portion, a cup seal, a cap and one or more valves. The rod assembly is configured to reciprocate within the cylinder so as to compress fluid within a space formed by the cylinder. The rod assembly is driven by the crank shaft. The one or more valves are configured to control air to the compressor. The one or more valves are removably coupled to the head portion, such that the one or more valves remain coupled to the head portion when the cap is detached from the coupling rod assembly.

A compressor having curved connecting rods, comprising cylinders (8), pistons (9), piston pins (10), curved connecting rods (11), a swing rod (12), a crank pin (13), a crankshaft (14) and the other components; when the compressor having curved connecting rods works, a power machine driving the crankshaft (14) to rotate, the rotation of the crankshaft (14) driving the crank pin (13) to push the swing rod (12) to swing left and right, and the movement, towards the left and right, of the swing rod (12) driving the curved connecting rods (11) and the pistons (9) to reciprocate within the cylinders (8) and perform work in a compression manner.

A gas transfer and depressurization system that is configured to transfer gas from a first location to a second location wherein during the transfer of gas the pressure of the first location is reduced. The gas transfer and depressurization system includes a drive chamber having an interior volume with a drive assembly movably disposed therein. A first cylinder and a second cylinder are operably coupled to the drive chamber on opposing sides thereof. The drive assembly includes a drive rod having portions extending into the first cylinder and second cylinder wherein the drive rod has pistons formed on opposing ends thereof. A controller is operably coupled to a compressed air source and is configured to provide compressed air into said drive chamber so as to reciprocally move the drive assembly. Gas blocks and coupling block are additionally present and facilitate flow of gas intermediate the first and second cylinders.

A drive system for a pump includes a housing defining an internal pressure chamber, a working fluid disposed within and charging the internal pressure chamber, and a reciprocating member disposed within the internal pressure chamber. A fluid displacement component has first and second surfaces. The first surface is configured to contact the working fluid and the second surface is configured to contact the process fluid. The area of the first surface is greater than the area of the second surface. A pull extends between and connects the reciprocating member and the fluid displacement component. The pull mechanically transfers a pulling force from the reciprocating member to the fluid displacement component.