A positive-displacement compressor having an automatic system for adjusting compression ratio and designed for installation in a conditioning or refrigeration system for a fluid includes a suction chamber for sucking the fluid with a variable suction pressure, a delivery chamber for delivering the fluid with a delivery pressure greater than the suction pressure, a compression chamber interposed between the suction chamber and the delivery chamber and communicating with the delivery chamber via one or more discharge ports, a compression element to compress the fluid to the compression pressure, a motor driving the compression element, and an adjusting system of the compression ratio. The adjustment system includes a mechanical valve interposed between the compression chamber and the delivery chamber that automatically varies discharge port apertures in response to a pressure differential between delivery chamber and compression chamber to instantaneously equalize compression and and delivery pressure and improve compressor efficiency.

A positive-displacement compressor having an automatic system for adjusting compression ratio and designed for installation in a conditioning or refrigeration system for a fluid includes a suction chamber for sucking the fluid with a variable suction pressure, a delivery chamber for delivering the fluid with a delivery pressure greater than the suction pressure, a compression chamber interposed between the suction chamber and the delivery chamber and communicating with the delivery chamber via one or more discharge ports, a compression element to compress the fluid to the compression pressure, a motor driving the compression element, and an adjusting system of the compression ratio. The adjustment system includes a mechanical valve interposed between the compression chamber and the delivery chamber that automatically varies discharge port apertures in response to a pressure differential between delivery chamber and compression chamber to instantaneously equalize compression and and delivery pressure and improve compressor efficiency.

The present disclosure is related to a slide valve, a slide valve adjustment mechanism and a screw compressor. The slide valve includes a static slide valve and a moving slide valve, wherein the static slide valve is fixedly installed in a slide valve cavity and provided with an axially-penetrating valve hole; a plurality of bypass holes communicating with the valve hole (110) are formed in the sidewall of the static slide valve, and an exhaust port is formed in the sidewall of one end of the static slide valve. The slide valve may avoid scraping between the slide valve and a screw rotor and the slide valve cavity. Gaps between the slide valve and parts which cooperate with same are reduced, so that the leakage is reduced while the energy efficiency of the compressor is increased.

The present disclosure is related to a slide valve, a slide valve adjustment mechanism and a screw compressor. The slide valve includes a static slide valve and a moving slide valve, wherein the static slide valve is fixedly installed in a slide valve cavity and provided with an axially-penetrating valve hole; a plurality of bypass holes communicating with the valve hole (110) are formed in the sidewall of the static slide valve, and an exhaust port is formed in the sidewall of one end of the static slide valve. The slide valve may avoid scraping between the slide valve and a screw rotor and the slide valve cavity. Gaps between the slide valve and parts which cooperate with same are reduced, so that the leakage is reduced while the energy efficiency of the compressor is increased.

A screw compressor according to an embodiment includes a rotor casing, a pair of screw rotors disposed in the rotor casing and engaging with each other, and a movable portion disposed so as to be movable in a rotor shaft direction of the pair of screw rotors. The movable portion includes liquefied liquid supply ports capable of supplying a liquefied liquid of a compressed gas toward tooth groove spaces formed by the pair of screw rotors.

A single screw compressor comprises a main rotor and at least one gate rotor, a casing for the main rotor having a discharge port at a discharge end of the casing, and a slide slidable within a bore in the casing adjacent the main rotor. The slide has a cut-out (6) between first (2) and second (4) sealing parts of the slide, the slide is slidable between a high volume ratio position where the cut-out (6) is within the casing and provides a path to the discharge port, and a low volume ratio position where the slide is beyond the discharge end of the casing to provide a fixed discharge path in the bore of the casing.

A single screw compressor comprises a main rotor and at least one gate rotor, a casing for the main rotor having a discharge port at a discharge end of the casing, and a slide slidable within a bore in the casing adjacent the main rotor. The slide has a cut-out (6) between first (2) and second (4) sealing parts of the slide, the slide is slidable between a high volume ratio position where the cut-out (6) is within the casing and provides a path to the discharge port, and a low volume ratio position where the slide is beyond the discharge end of the casing to provide a fixed discharge path in the bore of the casing.

Some embodiments of the present disclosure provide a slide valve for a compressor and a screw compressor with the slide valve. The slide valve for the compressor includes a slide valve main body (10), the slide valve main body (10) is provided with a gas replenishing chamber (11) therein, a surface, facing to a compression chamber of the compressor, of the slide valve main body (10) is provided with a gas replenishing outlet hole (12), and the gas replenishing outlet hole (12) is in communication with the gas replenishing chamber (11).

Some embodiments of the present disclosure provide a slide valve for a compressor and a screw compressor with the slide valve. The slide valve for the compressor includes a slide valve main body (10), the slide valve main body (10) is provided with a gas replenishing chamber (11) therein, a surface, facing to a compression chamber of the compressor, of the slide valve main body (10) is provided with a gas replenishing outlet hole (12), and the gas replenishing outlet hole (12) is in communication with the gas replenishing chamber (11).

A compressor unit including a screw compressor having a compressor housing that has a screw rotor chamber arranged in the compressor housing, two screw rotors that are arranged in the screw rotor chamber and are mounted on the compressor housing to be rotatable about a respective screw rotor axis, and at least one control slider, which is arranged in a slider channel of the compressor housing, is adjacent to both screw rotors and is movable in a direction of displacement parallel to the screw rotor axes and takes a form such that it affects the final volume and/or the initial volume, wherein there is provided on the screw compressor a compressor operational control unit that takes a form such that it performs a compressor operating function that assists at least one operation of the compressor unit.