A rotary compressor, comprising: a housing, comprising a lubricant oil storage part for containing lubricating oil; a compression mechanism disposed in the housing; a driving mechanism driving the compression mechanism, the driving mechanism comprising a rotation shaft, through-holes extending along the axial direction of the rotating shaft are disposed inside the rotating shaft, and the rotation shaft is in fluid connection with the lubricating oil storage part via the through-holes; and an oil level sensor in fluid connection with the through-holes inside the rotation shaft via a pressurized collection channel. Also disclosed is a rotation mechanism, comprising an oil level sensor in fluid connection with the through-holes inside the rotation shaft via the pressurized collection channel. Accurate and reliable detection of the lubricating oil in a compressor can be done using the pressurized collection channel and the oil level sensor, thus greatly saving cost and improving compressor reliability.

An automatic oil level retention system for a compressor and a method for controlling a same, including: a normal oil return mode and an auxiliary oil return mode. When a lubricating oil liquid level monitored by a liquid level detection unit in real time is above a required liquid level height, the system initiates only the normal oil return mode; and when the lubricating oil liquid level monitored by the liquid level detection unit in real time is below the required liquid level height, the system initiates the auxiliary oil return mode, and the auxiliary oil return mode is closed and the normal oil return mode is initiated after the lubricating oil liquid level monitored in real time is lifted above the required liquid level height.

An automatic oil level retention system for a compressor and a method for controlling a same, including: a normal oil return mode and an auxiliary oil return mode. When a lubricating oil liquid level monitored by a liquid level detection unit in real time is above a required liquid level height, the system initiates only the normal oil return mode; and when the lubricating oil liquid level monitored by the liquid level detection unit in real time is below the required liquid level height, the system initiates the auxiliary oil return mode, and the auxiliary oil return mode is closed and the normal oil return mode is initiated after the lubricating oil liquid level monitored in real time is lifted above the required liquid level height.

A compressor includes a compressor housing, a fastening device arranged on the compressor housing, and a support device, connected to the fastening device, for a temperature sensor, the support device being designed to hold, by pressing, the temperature sensor against a wall of the compressor housing. The support device has, for multiple connection to the fastening device, at least two sections, located on different sides of the temperature sensor, wherein, when the compressor is used as intended, the temperature sensor is designed to brace against the compressor housing from below.

A variable mechanical lubricant pump provides a pressurized lubricant for an internal combustion engine. The lubricant pump includes a delivery port which is fluidically connected to the engine, a control ring which shifts between a maximum and a minimum eccentricity position, a pump rotor having slidable vanes which rotate in the control ring, a control ring preload spring which pushes the control ring into the maximum eccentricity position, a hydraulic control chamber which pushes the control ring into the minimum eccentricity position, a pressure galley pump port fluidically connected to the engine, and an overpressure valve fluidically associated with the delivery port. The pressure gallery pump port charges the hydraulic control chamber with a gallery pressure to control a remote gallery pressure of the engine via a control chamber pressure in the hydraulic control chamber. The overpressure valve opens if an applied lubricant pressure exceeds a predefined maximum pressure limit.

A variable mechanical lubricant pump provides a pressurized lubricant for an internal combustion engine. The lubricant pump includes a delivery port which is fluidically connected to the engine, a control ring which shifts between a maximum and a minimum eccentricity position, a pump rotor having slidable vanes which rotate in the control ring, a control ring preload spring which pushes the control ring into the maximum eccentricity position, a hydraulic control chamber which pushes the control ring into the minimum eccentricity position, a pressure galley pump port fluidically connected to the engine, and an overpressure valve fluidically associated with the delivery port. The pressure gallery pump port charges the hydraulic control chamber with a gallery pressure to control a remote gallery pressure of the engine via a control chamber pressure in the hydraulic control chamber. The overpressure valve opens if an applied lubricant pressure exceeds a predefined maximum pressure limit.

A method for controlling the speed of a compressor with a controller as a function of the available gas flow. The method includes the steps of setting a desired value for the inlet pressure; determining the inlet pressure; and determining the speed. The method further includes controlling the speed of the compressor by reducing or increasing it depending on whether the inlet pressure is less than or greater than a set desired value until the inlet pressure is equal to the set desired value where the characteristic data of the compressor relating to the efficiency and/or the Specific Energy Requirement (SER) as a function of the speed and the inlet pressure is provided and the desired value of the inlet pressure is adjusted on the basis of the aforementioned characteristic data so that the efficiency of the compressor is a maximum or the SER is a minimum.

An oil-injected screw air compressor includes a first stage compression chamber, an air buffering chamber, a second stage compression chamber, an oil cooler, a plurality of sensors, and a controller. The air buffering chamber is coupled to the first stage compression chamber. The second stare compression chamber is coupled to the air buffering chamber. The oil cooler cools the lubricating oil for the first stage compression chamber, the air buffering chamber and the second stage compression chamber. The sensors are respectively located at outlets of the first stage compression chamber, the air buffering chamber and the second stage compression chamber. The controller respectively and dynamically controls flow rates of the lubricating oil entering into the first stare compression chamber, the air buffering chamber and the second stage compression chamber according to temperature and pressure data measured by the sensors.

A screw compressor system for a utility vehicle has at least one screw compressor, at least one screw compressor drive and at least one control and/or regulation unit. The control and/or regulation unit is connected to the screw compressor drive and is designed and configured such that it monitors, when the screw compressor is in operation, the ratio of idle time and switched on time of the screw compressor drive and this ratio controls and regulates to a predetermined range.

A method for controlling the speed of a compressor with a controller as a function of the available gas flow comprising the following steps: setting a desired value for the inlet pressure; determining the inlet pressure; determining the speed; controlling the speed of the compressor by reducing or increasing it depending on whether the inlet pressure is less than or greater than the set desired value until the inlet pressure is equal to the set desired value; providing the characteristic data of the compressor relating to the efficiency and/or the Specific Energy Requirement (SER) as a function of the speed and the inlet pressure; adjusting the desired value of the inlet pressure on the basis of the aforementioned characteristic data and in such a way that the efficiency of the compressor is a maximum or the SER is a minimum.