A method for controlling a compressor system comprising a plurality of compressors, wherein the compressor system is intended to maintain a predefined excess pressure in a pressurized fluid system, wherein decisions are met at fixed or variable intervals as to switching operations for adapting the system to current conditions, wherein —in a pre-selecting step, switching alternatives are excluded from the plurality of combinatorially available switching alternatives, —in a main selecting step, remaining switching alternatives are weighed against one another while referring to one or more optimization criterion (criteria) and optimum switching alternatives are selected from among the given criteria, and —in a control step, the selected switching alternative is output for implementation in the compressor system.

A compression mechanism portion housed in a closed case is provided with a partition plate located between a first cylinder and a second cylinder. The compression mechanism includes a first bearing discharge port formed to a first bearing and a first partition plate discharge port formed to the partition plate as discharge ports for discharging working fluid compressed in a first cylinder chamber, and also includes, as discharge port for discharging working fluid compressed in a second cylinder chamber, a second bearing discharge port formed to a second bearing and a second partition plate discharge port formed to the partition plate. A cross-sectional area of the first partition plate discharge port is formed to be smaller than a cross-sectional area of the first bearing discharge port, and a cross-sectional area of the second partition plate discharge port is formed to be smaller than a cross-sectional area of the second bearing discharge port.

A compression mechanism portion housed in a closed case is provided with a partition plate located between a first cylinder and a second cylinder. The compression mechanism includes a first bearing discharge port formed to a first bearing and a first partition plate discharge port formed to the partition plate as discharge ports for discharging working fluid compressed in a first cylinder chamber, and also includes, as discharge port for discharging working fluid compressed in a second cylinder chamber, a second bearing discharge port formed to a second bearing and a second partition plate discharge port formed to the partition plate. A cross-sectional area of the first partition plate discharge port is formed to be smaller than a cross-sectional area of the first bearing discharge port, and a cross-sectional area of the second partition plate discharge port is formed to be smaller than a cross-sectional area of the second bearing discharge port.

The present disclosure describes a load/unload control method for a compressor system with a rotating compressor connected to a pressure vessel. In the method, the present operating state can be monitored on the basis of a monitored/estimated electrical quantity of the compressor system, The method comprises an identification phase and an operational phase. In the identification phase, the compressor is operated at a constant rotational speed to generate two known pressures to the pressure vessel. At least one electrical quantity is monitored, and values of the electrical quantity corresponding to the pressure limits are stored. In the operational phase, reaching of a pressure limit may then be detected by comparing the present value of the monitored electrical quantity to the stored values.

A hydraulic pump is described, comprising at least one inlet duct for a fluid, at least one outlet duct for the fluid and at least one pumping unit interposed between the inlet and outlet ducts. At least one multifunction valve is interposed between the inlet duct, upstream of the pumping unit, and the outlet duct, downstream of the pumping unit, which valve is configured to divert the flow of fluid from the inlet duct to the outlet duct without the fluid flowing into the pumping unit. The multifunction valve comprises a valve body that defines an inner bypass channel in which a shutter element is axially movable, an actuator member operatively associated with the shutter element and configured to move it from a closing position to an opening position of the bypass channel, and an elastic contrast element operatively associated with the shutter element and configured to keep it in the first closing position of the bypass channel when such shutter element is not actuated by the actuator member. The actuator member consists of a bias spring manufactured with a shape memory alloy, configured to move the shutter element from the first closing position to the second opening position of the bypass channel when a predefined temperature value is reached.

The present invention relates to rotary screw positive displacement machines used as a vacuum pump wherein additional intake air is provided allowing cooling to the invention which permits extended operation at extreme vacuum pressure. The rotary screw nature of the vacuum pump allows operation without additional lubrication with the additional intake air ensuring that thermal expansion will not disrupt the tight tolerances of the invention. The invention allows simultaneous operation as a vacuum pump and air compressor.

The present invention relates to rotary screw positive displacement machines used as a vacuum pump wherein additional intake air is provided allowing cooling to the invention which permits extended operation at extreme vacuum pressure. The rotary screw nature of the vacuum pump allows operation without additional lubrication with the additional intake air ensuring that thermal expansion will not disrupt the tight tolerances of the invention. The invention allows simultaneous operation as a vacuum pump and air compressor.

A freezing device including a compressor that compresses sucked refrigerant using a compression mechanism and discharges compressed refrigerant includes a compressor, an inverter, and a controller. The compressor includes a motor, a low pressure unit, a compression space, a high pressure unit, a communication flow path, and a flow control valve. The inverter drives or stops the motor. The controller controls the inverter and the flow control valve. The controller performs, in stop control in which an operation of the compressor is stopped, braking control in which driving of the compression mechanism is prevented or suppressed, and pressure equalization control in which pressure in the high pressure unit is equalized with pressure in the low pressure unit.

Embodiments of the present disclosure provide a scroll compressor. The scroll compressor includes: a fixed scroll having an end plate and a fixed scroll wrap extending from the end plate; an orbiting scroll having an orbiting scroll wrap, the orbiting scroll wrap being engaged with the fixed scroll wrap to form a plurality of compression chambers for compressing a medium; a channel formed in the end plate of the fixed scroll, the channel leading to one compression chamber of the plurality of compression chambers; and a valve provided on the end plate of the fixed scroll, and configured to open when a pressure in the one compression chamber is higher than a predetermined pressure threshold so as to allow the medium in the one compression chamber to flow out of the one compression chamber through the channel. The scroll compressor according to the embodiments of the present disclosure, for example, can improve the performance of the scroll compressor.

Embodiments of the present disclosure provide a scroll compressor. The scroll compressor includes: a fixed scroll having an end plate and a fixed scroll wrap extending from the end plate; an orbiting scroll having an orbiting scroll wrap, the orbiting scroll wrap being engaged with the fixed scroll wrap to form a plurality of compression chambers for compressing a medium; a channel formed in the end plate of the fixed scroll, the channel leading to one compression chamber of the plurality of compression chambers; and a valve provided on the end plate of the fixed scroll, and configured to open when a pressure in the one compression chamber is higher than a predetermined pressure threshold so as to allow the medium in the one compression chamber to flow out of the one compression chamber through the channel. The scroll compressor according to the embodiments of the present disclosure, for example, can improve the performance of the scroll compressor.