Abstract: Transmission between drive shaft and a driven shaft, which transmission includes a housing and at least a driven gearwheel that is mounted on the driven shaft and a drive gearwheel that is mounted on a drive shaft. The housing is provided with an outlet opening, which outlet opening is placed in the radial extension of one of the gearwheels.

Abstract: The liquid level of a liquid supply compressor including a gas-liquid separator is dynamically monitored. A liquid supply gas compressor includes a compressor body; a gas-liquid separator separates liquid from compressed gas, to store the liquid; a liquid piping system supplies liquid stored to the compressor body; an internal pipe extends in an internal space of the gas-liquid separator, and includes at least two hole portions, with different disposition positions in a height direction, on an internal side to communicate with the piping system; and a sensor detecting pressure or temperature of fluid flowing through the piping system.

Abstract: Oil-injected multistage compressor device including a low-pressure compressor element (2) with a gas inlet (4a) for gas to be compressed and a gas outlet (5a) for low-pressure compressed gas and a high-pressure stage compressor element (3) with a gas inlet (4b) for low-pressure compressed gas and a gas outlet (5b) for high-pressure compressed gas. The gas outlet (5a) of element (2) is connected to inlet (4b) of element (3) via a conduit (6). The conduit (6) has a regulatable intercooler (9) configured to regulate the temperature at the gas inlet (4b) of the high-pressure stage compressor element (3) so that it is above the dew point. The intercooler (9) includes a regulatable air cooler and/or a regulatable water cooler, and is configured to adjust the temperature of the air or water by using a bypass conduit (16) and/or by screening off part of the intercooler (9).

Abstract: A compressor system can include a lubricant injection system useful to supply lubricant to an airend. The compressor system can include a variable lubricant flow valve which can be regulated by a controller on the basis of operating conditions of the compressor system. In one form the compressor system also includes an oil separator and/or an oil cooler with or without a thermal control valve. The controller can have one or more modes of operation, including a mode in which the controller regulates the flow of lubricant to the airend to increase an internal flow area of the valve when the airend is operated at an unloaded or loaded condition. In some forms the controller can regulate the lubricant flow valve and/or the thermal control valve and/or the lubricant cooler.

Abstract: Provided is a liquid supply mechanism including: a plurality of liquid supply sections each including a plurality of branch paths whose central axes intersect with each other, and a supply path having a side surface to which the plurality of branch paths of the plurality of liquid supply sections are directly connected, respectively, and supplying liquid, which is supplied from an upstream, to the branch paths.

Abstract: The present invention effectively cools air in a compression process at a high stage when an oil is supplied at the same pressure at a low stage and the high stage. Provided is a liquid-cooled type compressor including: a liquid-cooled type compressor body; at least one first nozzle; and at least one second nozzle, the at least one first nozzle and the at least one second nozzle each having a plurality of injection ports per nozzle and supplying a refrigerant through the injection ports into an inside of the compressor body, the second nozzle having the injection ports each having a diameter larger than a diameter of each of the injection ports of the first nozzle.

Abstract: Provided is an air compressor which helps to attain a proper discharge air temperature and which is superior in energy saving property.

Abstract: Method for cooling a liquid-injected compressor element, where a liquid is injected in the compression chamber of the compressor element (2) via an injection valve (13). The method includes the step of adjusting the quantity of liquid which is injected in the compression chamber of this compressor element (2) as a function of a specific adjusting parameter, irrespective of any other possible adjustments. The quantity of liquid to be injected is adjusted by using a second injection valve (19), which has the shape of an adjustable valve to this end.

Abstract: The invention relates to a device and a method for icing prevention regulation for a heat pump evaporator (3) in air conditioning systems of vehicles, composed of a subsection (1) of a refrigerant circuit which can be operated both as a heat pump and also as an air conditioning system. The device comprises the heat pump evaporator (3), an electrical or mechanical refrigerant compressor (4), a cooler fan (9) which is attached to the heat pump evaporator (3) and which draws ambient air (11) upstream from and through the heat pump evaporator (3) at an adjustable flow speed, and which thus permits a permanent flow of ambient air (11) over the heat pump evaporator surface, a first temperature sensor (6) in or on the refrigerant line (5, 5a) upstream from the heat pump evaporator (3) with respect to the heat pump operating direction, and a control and regulating unit (8).

Abstract: A device for controlling the oil temperature of an oil-injected compressor installation with a compressor element that is provided with a gas inlet and an outlet for compressed gas that is connected to an oil separator that is connected by an injection pipe to the compressor element. A cooler is affixed in a part of the injection pipe that can be bypassed by means of a bypass pipe. The device is also provided with an extra pipe that is intended to be connected in parallel with the bypass pipe and the cooler, and in which an energy recovery system can be connected. Additionally, the device is provided with a flow distributor through the cooler, the bypass pipe and the extra pipe, and a controller for controlling these temperature control devices at the outlet of the compressor element.

Abstract: The present disclosure provides a system including an oil flooded compressor operable for compressing a working fluid. A dehumidifier is positioned upstream of the compressor to reduce the humidity of working fluid entering the compressor and to cool oil while regenerating the dehumidifier. A heat exchanger positioned upstream of the compressor includes passageways for oil and compressible working fluid to be transported in a heat transfer relationship therethrough such that the temperature of the oil is reduced within the heat exchanger. A control system including an electronic controller is operable for controlling an inlet temperature of the oil entering the compressor, controlling an inlet temperature and humidity of working fluid entering the compressor and a discharge temperature of the working fluid exiting the compressor.

Abstract: The present invention relates to a technology of efficiently cooling a vacuum pump that produces a vacuum in a process chamber of a semiconductor manufacturing facility. The present invention provides a new type of vacuum pump cooling method that keeps the internal temperature of a vacuum pump at a predetermined level by circulating oil through rotors of the vacuum pump, such that it is possible to prevent a rapid increase in the temperature of the vacuum pump and smoothly lubricate bearings at the early stage of operation, whereby it is possible to ensure stability when performing processes and operating the pump and economically maintain the facility.

Abstract: A method for controlling a compressor device (1) with a compressor element (2) and oil circuit (14) with oil (15) that is injected into the compressor element (2) by a fan (19) via a cooler (18), with a bypass pipe (20) across the cooler (18), whereby when the temperature (T) of the compressor element (2) is less than a value (Tset), the method including the following steps: switching the fan (19) off; when the temperature (T) is still less than Tset, driving the oil (15) via the bypass pipe (20); when the temperature (T) is still less than Tset, decreasing the quantity of oil (15) that is injected into the compressor element (2) until the temperature (T) is equal to Tset.

Abstract: An aircraft includes a cooling compartment and an evaporative chiller configured to cool the cooling compartment. The evaporative chiller includes a compressor, an evaporator having airflow to the cooling compartment, and a condenser. The condenser has an exhaust airflow to cool the condenser. The evaporative chiller has a condensate removal system removing condensate produced by the evaporator using the exhaust airflow of the condenser to discharge the condensate.

Abstract: A vacuum pump includes a rotor and a housing, which define a vacuum chamber. Rotation of the rotor generates negative pressure in the vacuum chamber. The vacuum pump includes an oil introduction passage, which is connected to an oil pump to introduce oil into the vacuum pump, and an atmosphere communication passage, which opens in the atmosphere to introduce air into the vacuum pump. The vacuum pump further includes a valve and a spring, which serve as a communication control mechanism. The communication control mechanism provides communication between the vacuum chamber and the oil introduction passage and closes the atmosphere communication passage when the vacuum pump is driven. The communication control mechanism provides communication between the vacuum chamber and the atmosphere communication passage and closes the oil introduction passage when the vacuum pump is stopped.

Abstract: An approach is provided for compressing location trajectories based on map structure. A compression platform causes, at least in part, a mapping of at least one location trajectory to at least one map to determine one or more intersections traveled along the at least one location trajectory. The compression platform further determines at least one compression key based, at least in part, on one or more outgoing roads of the one or more intersections. The compression platform also causes, at least in part, a compression of the at least one location trajectory based, at least in part, on the at least one compression key.

Abstract: An oil separator capable of preventing breakage in a float with an extremely simple configuration is provided. An oil separator is to separate oil in a refrigerant that is discharged from a compressor and return the oil to the compressor. The oil separator includes: a tank, into which a refrigerant discharged from the compressor flows; a float having a hollow therein that is held vertically movably in the tank, the float moving up and down with a change of an oil level in the tank; and a needle valve to return oil in the tank to the compressor in accordance with up/down movement of the float. The float includes an equalizing tube having a lower end that opens at a bottom part in the float and an upper end that opens outside of the float and above the oil level in the tank.

Abstract: A compressor may include a shell, a compression mechanism, first and second temperature sensors, and a control module. The shell may define a lubricant sump. The compression mechanism may be disposed within the shell and may be operable to compress a working fluid. The first temperature sensor may be at least partially disposed within the shell at a first position. The second temperature sensor may be at least partially disposed within the shell at a second position that is vertically higher than the first position. The control module may be in communication with the first and second temperature sensors and the pressure sensor and may determine whether a liquid level in the lubricant sump is below a predetermined level based on data received from the first and second temperature sensors.

Abstract: A compressor includes a main body having in a housing a vane back-pressure space configured to project a vane forming a compression room for compressing gas, and a centrifugal oil separator. A discharge section to which the gas from the oil separator is ejected is formed in the housing, and the oil separator includes a pressure-adjusting valve configured to adjust pressure of the vane back-pressure space according to pressure of the discharge section. The pressure-adjusting valve is arranged in the oil separator without being affected by the gas ejected from the oil separator.

Abstract: A method and a device for compressing a gas-phase medium, particularly hydrogen or natural gas, in a single-stage or multistage process using at least one piston compressor, wherein the medium may have a water content up to total saturation with water. The medium to be compressed is heated before the compression at least to such point that the water is unable to condense out during the compression process, and the compressed medium undergoes a water separation process.

Abstract: A water cooled rotary screw compressor system.

Abstract: In order to improve a screw compressor comprising a housing, at least one screw rotor arranged in a compressor housing of the housing, a lubricant sump which is arranged on the high pressure side and in which lubricant collects, and a lubricant supply device which supplies lubricant from the lubricant sump to the at least one screw rotor, in such a manner that the amount of circulating lubricant can be kept as small as possible for adequate lubrication, it is suggested that the lubricant supply device comprise a first lubricant supply system and a second lubricant supply system, that the first lubricant supply system supply lubricant to the at least one screw rotor during operation of the screw compressor and that the second lubricant supply system additionally supply lubricant to the at least one screw rotor and thereby be activatable and deactivatable.

Abstract: In a water-supply line for performing water-supply to the rotors and the mechanical seal of a compressor, or in a condensed-water collection line for collecting condensed water of a dryer into the inlet port of the compressor, a water reservoir is provided at a position higher than the water-supply unit of the compressor. Moreover, there are provided a start-time water-supply line and a solenoid valve set up therein. Here, the start-time water-supply line establishes the connection between the lower portion of the water reservoir, and the inlet port of the compressor and the water-supply unit of the mechanical seal.

Abstract: A sliding vane rotary expander is used in a waste heat recovery system for a power plant. One example rotary expander has multiple stages with the vane assemblies disposed in bearing supported rings. Another example rotary expander has multiple stages with the vane assemblies disposed in an elliptical cavity. A balance valve equalizes the flow within the stages. Single stage rotary expanders may also be used.

Abstract: In a water injection air compressor including a compressor main body for compressing air, a water-feed line for feeding water to an actuation chamber in the compressor main body, an air release valve for releasing the compressed air from the compressor main body, and a control panel for executing an on-load operation mode in which water is fed into the actuation chamber and an air release valve is closed and a no-load operation mode in which the water is fed into the actuation chamber and the air release valve is opened, wherein the control panel further executes a dry operation mode in which the water is prevented from being fed into the actuation chamber and with the air release valve is opened.

Abstract: A rotary compressor or expander include a cylindrical housing chamber, a rotatable cylindrical rotor mounted eccentrically with respect to housing chamber center, a cylindrical rotor liner free to move around the rotor, and a pivoting generally circular arc vane hinged to the rotor liner. Cavity or buckets engraved to the outer surface of the rotor liner together with corresponding inlet nozzle flow provide additional momentum impulse transfer from working fluid to expander eccentric rotor. The inlet of the rotary expander is equipped with a rotating valve synchronous to the eccentric rotor, regulating the admission time and duration of the entering working fluid. The exhaust of the rotary compressor is equipped with either a check valve or a rotating valve synchronizing the fluid discharge time and duration.

Abstract: A compressor system includes a lubricant reservoir, a screw compressor, and a valve. The screw compressor includes a housing defining a compression chamber having a suction port, a discharge port, a first lubricant feed port located between the suction port and the discharge port, and a second lubricant feed port located between the discharge port and the first lubricant feed port. The valve is in fluid communication with the lubricant reservoir, the first lubricant feed port via a first lubricant feed passageway, and the second lubricant feed port via a second lubricant feed passageway. The valve is movable between a first position and a second position. In the first position, the valve fluidly connects the lubricant reservoir to the first lubricant feed passageway to direct lubricant to the first lubricant feed port. In the second position, the valve fluidly connects the lubricant reservoir to the second lubricant feed passageway to direct lubricant to the second lubricant feed port.

Abstract: In order to improve a screw compressor comprising a housing, at least one screw rotor arranged in a compressor housing of the housing, a lubricant sump which is arranged on the high pressure side and in which lubricant collects, and a lubricant supply device which supplies lubricant from the lubricant sump to the at least one screw rotor, in such a manner that the amount of circulating lubricant can be kept as small as possible for adequate lubrication, it is suggested that the lubricant supply device comprise a first lubricant supply system and a second lubricant supply system, that the first lubricant supply system supply lubricant to the at least one screw rotor during operation of the screw compressor and that the second lubricant supply system additionally supply lubricant to the at least one screw rotor and thereby be activatable and deactivatable.

Abstract: A compressor includes a main body having in a housing a vane back-pressure space configured to project a vane forming a compression room for compressing gas, and a centrifugal oil separator, wherein a discharge section to which the gas from the oil separator is ejected is formed in the housing, the oil separator includes a pressure-adjusting valve configured to adjust pressure of the vane back-pressure space according to pressure of the discharge section, and the pressure-adjusting valve is provided in the oil separator without being affected by the gas ejected from the oil separator.

Abstract: A compressor and an expander are provided in a refrigerant circuit of an air conditioner. In the compressor, refrigerator oil is supplied from an oil reservoir to a compression mechanism. In the expander, the refrigerator oil is supplied from an oil reservoir to an expansion mechanism. Internal spaces of a compressor casing and an expander casing communicate with each other through an equalizing pipe. An oil pipe connecting the compressor casing and the expander casing is provided with an oil amount adjusting valve operated on the basis of an output signal of an oil level sensor. When the oil amount adjusting valve is opened, the oil reservoir in the compressor casing and the oil reservoir in the expander casing communicate with each other to allow the refrigerator oil to flow through the oil pipe.

Abstract: An oil-cooled type screw compressor includes shafts mounted on rotors in a casing and extended to two sides of the rotors. Thrust plates rotate with the shafts. The thrust plates are sealed while spacing them from the rotors and define first and second spaces. Thrust bearings are arranged in the first and second spaces. An oil feed passage communicates with the one of the first and second spaces that is located on the side to apply a force against the thrust force to the thrust plates when boosted. An oil discharge passage communicates with the one of the first and second spaces that is located on the side to apply a force against the anti-thrust force to the thrust plates when boosted, to establish the communication between the space inside and an oil discharge target. An oil distribution passage distributes oil between the first space and the second space.

Abstract: A two-stage screw compressor has a low-pressure stage screw compressor and a high-pressure stage screw compressor integrally constructed. Compression space is formed by a male rotor and a female rotor, and operation gas is fed for compression to the compression space. A method of supplying lubrication oil prevents degradation of volumetric efficiency caused by return of lubrication oil, coming from a bearing and a shaft sealing device, to the low-pressure stage screw compressor. As a result, refrigeration capacity is improved and the amount of the lubrication oil is reduced.

Abstract: Device to prevent the formation of condensate in compressed gas coming from an oil-injected compressor element which is connected to an oil separator which is connected to the compressor element by an injection pipe, and wherein a cooler is provided in the injection pipe which can be bridged by means of a bypass. A controlled mixing valve is connected to the injection pipe and to the bypass, and a control device controls the mixing valve to adjust the compressed air temperature by adjusting the flow distribution through the mixing valve.

Abstract: A screw compressor is disclosed wherein a pair of rotor shafts are disposed horizontally and an oil sump is formed at the bottom of a bearing casing which accommodates bearings for supporting the rotor shafts, a bearing lower portion being soaked into oil present in the oil sump for lubrication. The screw compressor comprises a chamber provided separately from the bearing casing, an oil line for communication between the oil sump in the bearing casing and the chamber and oil level detecting means disposed in the chamber. According to this structure, the oil level in the bearing casing can be checked accurately and there is no fear of oil shortage in the bearings.

Abstract: A water-lubricated compressor has a discharge on-off valve in a discharge channel located between a discharge port of a compressor body and a water separating/recovering unit. A water circulation on-off valve is disposed in a water circulation channel located between a water cooler and a water supply portion in the compressor body. A gas release channel provides communication between a gas phase portion of the water separating/recovering unit and the exterior of the water separating/recovering unit. A gas release on-off valve is disposed in the gas release channel. When the compressor body is not in operation, the discharge on-off valve and the water circulation on-off valve are closed and the gas release on-off valve is opened, allowing water to be recovered to the water separating/recovering unit. When there is no demand for compressed gas, it is possible to remove water from the water cooler, which otherwise may be damaged.

Abstract: Method for cooling a liquid-injected compressor element, whereby a liquid is injected in the compression chamber of this compressor element (2) via an injection valve (13), said method comprising the step of adjusting the quantity of liquid which is injected in the compression chamber of this compressor element (2) as a function of a specific adjusting parameter, irrespective of any other possible adjustments, wherein the quantity of liquid to be injected is adjusted by means of a second injection valve (19), which has the shape of an adjustable valve to this end.

Abstract: In a water injection air compressor including a compressor main body for compressing air, a water-feed line for feeding water to an actuation chamber in the compressor main body, an air release valve for releasing the compressed air from the compressor main body, and a control panel for executing an on-load operation mode in which water is fed into the actuation chamber and an air release valve is closed and a no-load operation mode in which the water is fed into the actuation chamber and the air release valve is opened, wherein the control panel further executes a dry operation mode in which the water is prevented from being fed into the actuation chamber and with the air release valve is opened.

Abstract: A method for lubricating a screw expander includes condensing a mixture of working fluid and lubricant fed from the screw expander, through a condenser. At least a portion of the mixture of working fluid and lubricant fed from the condenser is pressurized from a first pressure to a second pressure through a pump. The method also includes separating the lubricant from the condensed working fluid of the at least portion of the mixture via a separator and feeding the lubricant to the screw expander; or separating the lubricant from the working fluid of the at least portion of the mixture via an evaporator and feeding the lubricant to the screw expander; or feeding the at least portion of the mixture of condensed working fluid and lubricant to the screw expander; or combinations thereof.

Abstract: An improved, piston-based, pressure-transforming barrier fluid support apparatus is disclosed that can support both the pressurized and unpressurized barrier fluid requirements of a shaft-driven machine from a single unit. The disclosed apparatus includes both a pressurized section that stores, cools, cleans, and pressure regulates pressurized barrier fluid, and an unpressurized section that stores, cools, and cleans unpressurized barrier fluid. The disclosed apparatus causes debris in the pressurized barrier fluid to gravitationally migrate away from the piston, so as to prevent piston fouling. If the piston rod becomes detached, it is expelled downward for enhanced safety. Removable covers and/or a removable cylinder can provide enhanced access for cleaning and maintenance. Embodiments include a common cover that is shared by the pressurized and unpressurized sections and serves as a common manifold for cost-efficient fluid connections thereto.

Abstract: A fluid compressing system includes: a rotary compressor including a housing defining an oil chamber and an oil-releasing port in fluid communication with the oil chamber; a discharging pipeline connected to the housing for passage of a high pressurized fluid therethrough; an oil-adjusting tank connected to the discharging pipeline and the oil-releasing port for receiving lubricant oil from the oil chamber so as to alleviate oil swirling in the oil chamber; an oil filter connected to the discharging pipeline for separating the lubricant oil from the high pressurized fluid; and a first capillary connected to the oil filter and the housing for recycling filtered lubricant oil from the oil filter into the oil chamber.

Abstract: Device to prevent the formation of condensate in compressed gas coming from an oil-injected compressor element (2) which is connected to an oil separator (9) which is connected to the above-mentioned compressor element (2) by means of an injection pipe (12), and whereby a cooler (14) is provided in the above-mentioned injection pipe (12) which can be bridged by means of a bypass (21), characterised in that it is provided with a controlled mixing valve (16) which is connected to the above-mentioned injection pipe (12) and to the above-mentioned bypass (21), and with a control device (38) for controlling said mixing valve (16) for the adjustment of the compressed air temperature (Tw) by adjusting the flow distribution through the mixing valve (16).

Abstract: Compressor installation with a water-injected compressor element to which an inlet line (4) and an outlet line (5) are connected, an air inlet filter (13) to which said inlet line (4) is connected, a water separator (6) into which said outlet line (5) feeds and a return line (7) between this water separator (6) and the compressor element (2), characterised in that said air inlet filter (13) takes the form of a wet filter to which a water supply is connected.

Abstract: A compressor of this invention includes a flow passage supplying lubricant to an outlet bearing and to an inlet bearing. An orifice is disposed within the flow passages for controlling lubricant flow to the bearing assemblies. A choke orifice is disposed in series with one of the orifices for either the inlet or outlet for controlling lubricant flow relative to the other orifice.

Abstract: A volumetric compressor comprising: a casing provided with a suction chamber and a delivery chamber, between which a pair of screw rotors is included; a pan containing oil, and a delivery adjustment unit equipped with a slide valve, cooperating with the rotors and with a fluid-operated actuator, in which it is possible to identify an active chamber with a sliding piston connected to the slide valve. The adjustment unit comprises a flow switching unit, that connects the active chamber of the actuator to the pan and to the suction chamber and comprises a static flow switch removably associated with a switching solenoid valve electrically connected to a control unit. The switching solenoid valve is suited to be associated, alternatively, with different static flow switches that make it possible to obtain deliveries of compressed fluid varying discretely or continuously, depending on the position of the slide valve with respect to the rotors.

Abstract: A rotary screw compressor with an oil feed system that has a plurality of oil orifice nozzles to feed oil to the compressor rotors and the compressor bearings. One of the oil orifice nozzles is generally always provided with a regulated flow of oil. At least one and preferably two on/off oil valves can be selectively opened and closed. Each of the on/off oil valves are of a different size and are selectively opened and closed to step regulate the amount of oil being fed to the compression chamber according to a predetermined compression chamber discharge temperature.

Abstract: A fluid compressing system includes: a rotary compressor including a housing defining an oil chamber and an oil-releasing port in fluid communication with the oil chamber; a discharging pipeline connected to the housing for passage of a high pressurized fluid therethrough; an oil-adjusting tank connected to the discharging pipeline and the oil-releasing port for receiving lubricant oil from the oil chamber so as to alleviate oil swirling in the oil chamber; an oil filter connected to the discharging pipeline for separating the lubricant oil from the high pressurized fluid; and a first capillary connected to the oil filter and the housing for recycling filtered lubricant oil from the oil filter into the oil chamber.

Abstract: A muffler that is externally mounted to a housing shell of a compressor. To externally mount the muffler to the housing shell and prevent unnecessary vibration of the muffler during compressor operation, an attachment device connects an essentially central portion of the muffler to the housing shell. The attachment device may also be adapted to house a pressure- or temperature-related sensor device.

Abstract: A water-injected compressor, which injects the water inside the separator 3 into the compressor and discharges the water along with compressed air into the separator and then gains condensed and separated water, has the compressor stopping and then, if staying at a stop for a predetermined duration of time without activating, becoming activated and operating for a set duration of time.

Abstract: A screw-type vacuum pump (1) is tempered such that characteristics of the pump are not substantially altered when the pump is subjected to thermal stress. In order to achieve said aim, cooling is adjusted according to an operating state of the screw-type vacuum pump (1), preferably to maintain a substantially constant pump gap (4).

Abstract: The invention relates to a method for controlling the oil recirculation in an oil-injected screw-type compressor which, between the oil separator (10) and the compressor element (1), comprises an oil recirculation conduit (17) in which an oil cooler (18) is installed which is bridged-over by a passage or bypass (30), said control taking place by means of a thermostatic valve (24) having a valve element (26) which can be moved by means of a temperature-sensitive element (34). During the transition of the screw compressor from the unloaded to the loaded condition, the effect of the temperature-sensitive element (34) temporarily is switched off at least partially, such that the valve element (26) takes a position in which, regardless of the temperature of the oil, at least the bypass (30) is open and thus the recirculation of oil from the oil separator (10) to the compressor element (1) takes place through this bypass (30).