A vacuum generation system and method utilizes a dual-action piston-cylinder vacuum generation system to evacuate a vacuum storage. Saturated steam of higher than ambient pressure is inserted into a condensation cylinder with two chambers separated by a movable piston. Steam moves the piston to fill one chamber while expel gaseous content and condensate out of the other chamber. Steam is then condensed to a rough vacuum (RV) state by cooling. By repeated operations of inserting and condensing steam in each chamber alternatively, a sustained vacuum generation is achieved. A multi-level vacuum storage is also disclosed with a high vacuum (HV) storage placed inside a rough vacuum (RV) storage to reduce leakage as well as mechanical stresses. The vacuum generation system and method is extended for creating a prime mover or actuator to drive vacuum pumps maximizing thermal energy usage for increased vacuuming capacity.

A compressor moves a fluid from an inlet to an outlet and provides a pressure differential there between due to respective pistons moving in and out of a plurality of piston chambers via a piston rod. A rotating shaft extends through a grooved end plate, and the rotating shaft is connected to either the grooved end plate or the piston rod. The grooved end plate defines an off center or eccentric groove. A bearing extends from the piston rod and fits within the groove such that when the rotational motion of the shaft rotates either the piston rod or the grooved end plate, the piston rod slides back and forth relative to the rotating shaft. Each position of the bearing within the groove determines a corresponding position of the piston rod relative to the rotating shaft. Each pair of pistons may extend from a single, continuous piston rod.

A variable-pressure air pump includes a first cylinder with a first chamber and a second cylinder with a second chamber movably connected with one another. The second chamber fluidly communicable with the outside of the variable-pressure air pump selectively. A discharge device includes a connecting member and a switch movably connected with one another. The connecting member defines at least one discharge hole fluidly connecting with the second chamber. The switch has at least one flow guide portion and at least one blocking portion. The switch is movable between a first position in which the at least one flow guide portion is adjacent and opens to the at least one discharge hole and a second position in which the at least one blocking portion is adjacent to and blocks the at least one discharge hole.

A pump system includes a housing defining a first internal volume and a second internal volume, a first piston positioned to separate the first internal volume into a first chamber and a second chamber, a second piston positioned to separate the second internal volume into a third chamber and a fourth chamber, a directional control valve (DCV) fluidly coupled to the second chamber and the fourth chamber, a first relief valve fluidly coupled to the DCV via a first control line and the second chamber via a first sensing line, a first orifice positioned along the first sensing line, a second relief valve fluidly coupled to the DCV via a second control line and the fourth chamber via a second sensing line, and a second orifice positioned along the second sensing line.

The invention relates to a method for operating a piston compressor (100) having a reciprocating piston (111) in a cylinder (110), wherein an inlet valve (112) and an outlet valve (113) are provided in the cylinder (110) on the side of a medium (b) which is to be compressed and conveyed, wherein the reciprocating piston (111) is moved to and fro by way of a hydraulic drive (120, 121) with a hydraulic piston (120) with the use of a hydraulic medium (a) in a first volume (141), with which the reciprocating piston (111) is loaded on the side of the hydraulic drive (120, 121), wherein, if required, hydraulic medium (a) is fed into the first volume (141) and/or is discharged from the first volume (141) in a manner which is dependent on a position of the hydraulic piston (120) and/or a rotational angle ((p) of a shaft (121) which is provided for moving the hydraulic piston (120) in relation to a position (x) of the reciprocating piston (120) and/or a pressure (p) in the first volume (141), and to a piston compressor (100) of this type.

A GM cryocooler includes a first cold head including a first displacer that is reciprocable in an axial direction, a first drive piston that drives the first displacer in the axial direction, and a first drive chamber that houses the first drive piston; a second cold head including a second displacer that is reciprocable in the axial direction, and a second cylinder that houses the second displacer; a first intake valve that is connected to both the first drive chamber and the second cylinder so as to supply working gas in parallel to the first drive chamber and the second cylinder; and a first exhaust valve that is connected to both the first drive chamber and the second cylinder so as to collect the working gas in parallel from the first drive chamber and the second cylinder.

An apparatus and method for sensing the position of a piston in a valve in a gas compressor or the position of a piston in a free piston engine. The apparatus includes a plurality of valve sensors, a plurality of magnets, and a plurality of valve sense modules coupled to the valve sensors and a controller coupled to the plurality of valve sense modules. The method includes processing information received from the valve sensors to determine the linear position of the valves in the gas compressor or a piston in a free piston engine.

The purpose of the present invention is to provide a reciprocating compressor which is a compact, light-weight, portable air compressor such that deterioration of performance due to problems such as wear on the surface finish of the cylinder when the compressor is used for a long period of time outside the operating temperature range thereof is prevented. To achieve this, the cylinder temperature is detected, and control is carried out so that the compressor is restarted at a lower restart pressure when the temperature is lower than a prescribed value and stopped (and also restarted, preferably) at a low pressure when the temperature is higher than a prescribed value.

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.

A method and apparatus for controlling a compressor to switch a cylinder mode and an air conditioner system. The method for controlling a compressor to switch a cylinder mode includes: determining that a compressor is required to switch from a single-cylinder operation mode to a two-cylinder operation mode; determining whether a system pressure differential is within a first preset system pressure differential interval; if not, adjusting a system control parameter such that the system pressure differential is within the first preset system pressure differential interval; and controlling the compressor to switch from the single-cylinder operation mode to the two-cylinder operation mode.