Abstract: A method for providing supplemental flow control of working fluid through a transport climate control circuit during a start-stop cooling operation mode is provided. The method includes closing a main liquid suction solenoid valve disposed between a condenser and an evaporator of the transport climate control circuit when the compressor is OFF. The method also includes monitoring a climate controlled space temperature within a climate controlled space. When the climate controlled space temperature is greater than or equal to a setpoint temperature, the method includes turning a compressor ON, and opening the main liquid suction solenoid valve when a suction pressure at the suction port of the compressor is less than or equal to a predetermined suction pressure threshold. When the climate controlled space temperature is less than or equal to the setpoint temperature, the method includes turning the compressor OFF, and closing the main liquid suction solenoid valve.

Abstract: Manual hydraulic override pumps for use with actuators are described herein. An example apparatus includes a manifold including a reservoir port to be fluidly coupled to a reservoir of fluid, a pump port to be fluidly coupled to a pump, a first actuator port to be fluidly coupled to a first chamber of an actuator, and a second actuator port to be fluidly coupled to a second chamber of the actuator. The example apparatus also includes a rotor disposed in a cavity formed in the manifold. The rotor is rotatable between a first actuating position in which the rotor fluidly couples the first actuator port and the pump port, and a second actuating position in which the rotor fluidly couples the second actuator port and the pump port.

Abstract: There is provided a wobble plate piston water pump for use in a pressure washer and driven by a driving source, the water pump includes a pump body, a wobble plate, four or more pistons and a water passage defined by a water inlet and a water outlet. The driving source being electric powered and having a power consumption of less than or equal to a 15 ampere draw at 120 volts or 220 volts or the driving source being gas powered and having an engine displacement of less than or equal to 250 cubic centimetres.

Abstract: A two-stage variable-displacement oil pump includes a casing having a suction port for suctioning oil stored in an oil tank and a discharge port for discharging, to a main gallery; an outer cam ring rotatably installed with respect to a pivot shaft provided inside the casing and having a rotary chamber therein; a rotor installed to be eccentric relative to the outer cam ring, rotating in concert with a rotation of a driving shaft, and including a plurality of vanes radially and slidably installed on an outer circumferential surface of the rotor; a support spring having one end contacting a spring support part formed on an outer side surface of the cam ring and the other end contacting an inner side surface of the casing; and a regulating chamber provided between the outer cam ring and the casing.

Abstract: Disclosed is a hydraulic pressure supply system of an automatic transmission for a hybrid vehicle. A hydraulic pressure supply system of an automatic transmission for a hybrid vehicle pumps oil stored in an oil pan using an oil pump to supply the oil to a high pressure part and a low pressure part. The hydraulic pressure supply system includes a separate motor/generator cooling route which uses an oil flow recirculated in a line regulator valve and an another oil flow recirculated in a reducing valve.

Abstract: A variable-capacity compressor that includes a housing having an inlet for receipt of refrigerant and an outlet for return of refrigerant, and a plurality of compressing elements contained in the housing between the inlet and the outlet. The variable capacity compressor includes a valve having an electrical control. The valve is dedicated to fewer than all of the compressing elements. The valve is movable between a first state which communicates refrigerant flow to the compressing elements, and a second state that reduces or stops flow to the compressing elements. In an embodiment of the invention, an unloading controller has an operational modulation mode that includes cycling the valve between on and off states to provide a portion of compressor capacity. The unloading controller is further programmed to provide a minimum delay time between transitions between the first and second states, but no maximum dwell time between transitions.

Abstract: Hydraulic drive and method for driving a pressure booster of a high-pressure apparatus. The hydraulic drive includes a pressure medium pump having one of a constant displacement pump and a pump conveying a constant volume per revolution, a servo motor coupled to drive the pump, and a controller structured to at least one of electrically control, regulate and switch the servo motor, which is arranged on at least one of a low pressure side and a high pressure side of the pressure booster.

Abstract: A multi-stage centrifugal pump assembly allows for multiple fixed ratio pressure levels. The multiple pressure levels permit optimization of actuation loops without the need for pressure regulators, and can be used directly by the actuators.

Abstract: A fuel system includes a pump unit having at least a fixed displacement pump supplying pressurized flow. A fuel control assembly receives flow from the pump unit and includes at least one metering valve and at least one throttling valve. A control (bypass valve control) for the fixed displacement pump receives first and second pressure signals indicative of a pressure differential across the throttling valve, or across the metering valve/throttling valve combination, for altering output from the fixed displacement pump in response to the pressure differential. In other embodiments, the pump unit includes a centrifugal pump and a fixed displacement pump that can be fully or partially redundant depending on sizing of the pumps, and the system requirements.

Abstract: The present disclosure relates to a hydraulic system of a construction machine. The hydraulic system of the construction machine includes: an electronic proportional pressure reducing valve configured to control a flow rate, to which a maximum pressure is input as a control current value, and which is set to a minimum flow rate; a gear pump configured to provide pilot operation oil to the EPPRV; a shuttle valve configured to compare a pressure of first pilot operation oil passing through the EPPRV and a pressure of a flow rate control signal, and output second pilot operation oil having the greater pressure; a hydraulic pump of which a swash plate angle is controlled by the second pilot operation oil; and a pump control device configured to control a pressure of the EPPRV to be decreased from a maximum pressure by a predetermined inclination when the flow rate control signal is generated.

Abstract: The invention relates to a wind turbine being provided with a fluid displacement means for ensuring a certain increased pumping capacity at a certain reduced rotational speed of the main shaft of the rotor and thus of a drive shaft from a gear box of the wind turbine. The invention also relates to a wind turbine being provided with fluid displacement means for ensuring a certain increased pumping capacity at a certain increased rotational speed of the main shaft of the rotor and thus of a drive shaft from a gear box of the wind turbine. The means may be mechanical, hydraulic, pneumatic or electrical. Additionally, the invention relates to a method for operating a wind turbine being provided with such fluid displacement means.

Abstract: A hydraulic power device for effecting operation of at least one load, the hydraulic power device including a motor having a predetermined motor speed rating and motor power rating, at least one pump operably coupled to the motor, the pump being configured to provide, to the at least one load, a predetermined hydraulic fluid flow at the predetermined motor speed rating, and a variable frequency drive connected to the motor, the variable frequency drive being configured to effect operation of the motor at a speed above the predetermined motor speed rating such that the at least one pump operates to provide an excess hydraulic fluid flow during operation of the motor substantially above the predetermined motor speed rating where the excess fluid flow is greater than the predetermined hydraulic fluid flow.

Abstract: An oil pump unit with a variable flow rate includes lubrication pumps and a control pump that are driven by rotation of a crankshaft of an engine, and changes an oil supply amount from the control pump to each part of the engine, in which the control pump includes a plurality of oil pumps that have different discharge rates.

Abstract: A method is provided for regulating a charge air pressure of an engine having an exhaust gas supercharger, a fresh gas supply device, an air system having an air treatment system and a compressor chargeable by the supercharger, and an engine controller. The method detects an engine torque requirement; determines a current charge air pressure and a current pressure of the air system; compares the current charge air pressure to a target charge air pressure corresponding to the torque requirement, compares the current air system pressure to a target operating air system pressure, and regulates the charge air pressure by suppressing supply of compressed air from the supercharger to the compressor when the current charge air pressure is less than the corresponding target charge air pressure and the current pressure of the air system is greater than or equal to the target operating pressure of the air system.

Abstract: A system for changing a pump displacement configuration includes a blender that provides low-pressure fluid to a pump. The pump has a power end and fluid end, where the fluid end includes a number of plungers. The system includes an actuator that couples the power end with a selectable subset of the plungers. The system further includes a controller that selects a subset of the plungers according to a job pumping rate, a job pumping pressure, and/or a fluid end failure event indicator. The controller further commands the actuator to couple the selected subset of the plungers to the power end.

Abstract: A pump arrangement for fluid in an automotive transmission system includes, but is not limited to a first, low-pressure pump stage and a second, high-pressure pump stage, the first pump stage supplying low-pressure fluid to a lubrication/cooling system and to the inlet of second pump stage, which supplies high pressure fluid to a hydraulic control system. Fluid from both systems is returned via a reservoir and filter to the first pump stage.

Abstract: A fuel supply installation for a turbojet including two volumetric pumps for combining their flow rates is disclosed. The pumps include a main pump dimensioned for the full gas rate and an auxiliary pump controlled and dimensioned to provide the supplementary flow rate necessary on ignition.

Abstract: A transmission is provided for a mobile machine. The transmission may have a plurality of available gear combinations selectively engaged to produce multiple stepped output ratios. The transmission may also have a first fluid pump and a second fluid pump. The first fluid pump may be configured to pressurize a first flow of fluid. The second fluid pump may have variable displacement to pressurize a second flow of fluid. At least one of the first and second flows of fluid may be directed to cause selective engagement of the plurality of available gear combinations.

Abstract: A fuel delivery and control system is provided including a dual pump fluid circuit configuration comprising a fixed positive displacement pump sized to supply the main engine burn flow ranging from above windmill through cruise, a positive displacement actuation pump including a variable pressure regulator, wherein the actuation pump is sized to supply fluid to engine actuators, valves and other hydraulically operated engine components and a pump flow sharing system interconnecting the two pumps. The combined flow from the two pumps is sufficient to meet the engine flow demand for windmill relight and maximum flow conditions. During cruise or normal operating conditions, the pumps operate in completely isolated flow circuits, minimizing recirculation and therefore heat input into the fuel supply system.

Abstract: A fuel supply system includes a fuel metering pump and a servo-flow pump that are used to supply fuel to one or more fuel manifolds and one or more fluid-operated actuators, respectively. The fuel metering pump and the servo-flow pump are driven by the same electric motor(s).

Abstract: A fuel delivery and control system is provided including a dual pump fluid circuit configuration comprising a fixed positive displacement pump sized to supply the main engine burn flow ranging from above windmill through cruise and a variable displacement pump sized to supply fluid to engine actuators, valves and other hydraulically operated engine components with a pump flow sharing system interconnecting the two pumps. The combined flow from the two pumps is sufficient to meet the engine flow demand for windmill relight and maximum flow conditions. During cruise or normal operating conditions, the pumps operate in completely isolated flow circuits, minimizing recirculation and therefore heat input into the fuel supply system.

Abstract: A split-pressure, dual-pump system for supplying hydraulic fluid to a multi-speed transmission is provided. The system includes a low-pressure work circuit operatively connected to a fixed displacement pump, and a high-pressure work circuit operatively connected to a variable displacement pump. The system also includes a regulator valve fluidly coupled to the variable displacement pump via a decrease circuit and an overage circuit for regulating the flow of fluid to the high-pressure work circuit. The invention consists of separating the high-pressure needs of the system into a separate work circuit from the low-pressure needs of the system, and optimizing pump design separately for each work circuit to maximize transmission efficiency and reduce parasitic losses. A method of supplying hydraulic fluid to a multi-speed transmission at variable flow and pressure is also provided.

Abstract: A device including a first discharge passage from a first rotor assembly to an engine, a first return passage that returns to an intake side of the first rotor assembly, a second discharge passage from a second rotor assembly to the engine, a second return passage that returns to an intake side of the second rotor assembly, and a pressure control valve whose valve main body is provided between a discharge port from the second rotor assembly and the first discharge passage. The first discharge passage and the second discharge passage are coupled, and a flow passage control is executed in each of: a low revolution range; an intermediate revolution range; and a high revolution range.

Abstract: Method for adjusting a compressed air installation using several electrically driven compressors of what is called the “loaded/unloaded” type and/or the turbo compressor type and/or the compressor type with variable rotational speed, wherein these compressors are each connected to a single compressed air network with their outlets, and wherein use is made of a control box which makes it possible to adjust the pressure in the compressed air network around a target pressure to be set. The adjustment takes place by controlling the flow of one or several of the compressors, in particular in order to increase the overall flow supplied by the compressors when the pressure drops too much, and in order to lower the overall supplied flow when the pressure becomes too high.

Abstract: A pump head suitable for use in a fuel pump for a common rail fuel injection system, comprises a pump head housing defining a plunger bore and a pumping chamber. Fuel is pressurized within the pumping chamber by a plunger reciprocating within the plunger bore. The pump head housing includes an inlet valve arrangement for controlling fuel flow into the pumping chamber. The inlet valve arrangement includes a valve member movable between open and closed positions in response to fuel pressure within a gallery. The gallery communicates with an external chamber defined by a closure means externally mounted to the pump head housing. In use, the gallery communicates with a source of low-pressure fuel via the external chamber. The pump head housing has a projection which locates the closure member on the pump head housing.

Abstract: A compressor control system includes at least one variable compressor, at least one fixed-capacity compressor, and a controller. The controller modulates the variable compressor based on a suction pressure reading of the variable compressor. In addition, the controller selectively toggles the fixed-capacity compressor between a run mode and a shutdown mode based on an operating parameter of the variable compressor.

Abstract: The present invention discloses a control apparatus for a linear compressor which can vary a cooling force and prevent an inrush current. The control apparatus for the linear compressor includes a coil winding body laminated on the linear compressor, a first capacitor connected in series to the coil winding body, a capacitance varying unit being formed in a parallel structure to the first capacitor, and having a capacitor switch, and a control unit for inducing an output change of the linear compressor, by varying the whole capacitance of the control apparatus by controlling the capacitor switch.

Abstract: A fast fill pump system for a self-propelled field sprayer includes high capacity centrifugal pump for tank filling. The centrifugal pump is connected in parallel with the fill connection and primed by a lower capacity diaphragm spraying pump. Two check valves and a pressure sensor allow the sprayer control to automatically control the pump priming and tank filling with the activation of one switch. The two-pump system preserves tank filling speed, even during operation of eductor or tank agitation functions. The centrifugal pump can be removed and the spraying pump operated to fill the tank without substantial base machine modification.

Abstract: A split-pressure, dual-pump system for supplying hydraulic fluid to a multi-speed transmission is provided. The system includes a low-pressure work circuit operatively connected to a fixed displacement pump, and a high-pressure work circuit operatively connected to a variable displacement pump. The system also includes a regulator valve fluidly coupled to the variable displacement pump via a decrease circuit and an overage circuit for regulating the flow of fluid to the high-pressure work circuit. The invention consists of separating the high-pressure needs of the system into a separate work circuit from the low-pressure needs of the system, and optimizing pump design separately for each work circuit to maximize transmission efficiency and reduce parasitic losses. A method of supplying hydraulic fluid to a multi-speed transmission at variable flow and pressure is also provided.

Abstract: A first pump of small capacity and a second pump of large capacity are connected directly with each other and are driven by a variable-speed motor. The rotational speed of the variable-speed motor is controlled by a control device. In a first mode, a first discharge line of the first pump and a second discharge line of the second pump are disconnected with each other, making the first pump unloaded. With the first pump in the unloaded state, a constant-horsepower operation is performed, where the discharge fluid is brought into a high pressure by relatively small torque. In a second mode, the first discharge line and the second discharge line are connected with each other by a switching valve. With the first and second discharge lines in the connected state, a constant-horsepower operation is performed, where a high flow rate of discharge fluid is discharged at relatively low rotational speed.

Abstract: A variable capacity rotary compressor to prevent eccentric bushes from rotating faster than a rotating shaft, and includes upper and lower compression chambers having different interior capacities thereof, and the rotating shaft with upper and lower eccentric cams being provided thereon to be eccentric from the rotating shaft in a common direction. Upper and lower eccentric bushes are fitted over the upper and lower eccentric cams, respectively, with a slot provided there between. A locking pin changes a position of the upper or lower eccentric bush to a maximum eccentric position. Upper and lower brake units are, respectively, provided between the upper eccentric cam and the upper eccentric bush, and between the lower eccentric cam and the lower eccentric bush. The upper and lower brake units, respectively, include first and second upper brake balls, and first and second lower brake balls, to restrain the upper and lower eccentric bushes.

Abstract: A variable capacity rotary compressor including first and second compression chambers having different capacities, and a rotating shaft. First and second eccentric cams are mounted to the rotating shaft to be eccentric in a same direction. First and second eccentric bushes are fitted over the first and second eccentric cams to make an angle between eccentric lines of the first and second eccentric bushes be less than 180°. A locking pin functions to change a position of the first or second eccentric bush to a maximum eccentric position. Further, a slot is formed on the rotating shaft between the first and second eccentric bushes. In this case, the slot having a predetermined length is formed to have a same angle as the angle between the eccentric lines of the first and second eccentric bushes. The locking pin is inserted into the slot.

Abstract: A variable capacity rotary compressor including upper and lower compression chambers having different interior capacities, and a rotating shaft. Upper and lower eccentric cams are provided on the rotating shaft to be eccentric from the rotating shaft in a same direction. Upper and lower eccentric bushes are fitted over the upper and lower eccentric cams, respectively, in such a way that a maximum eccentric part of the upper eccentric bush is opposite to that of the lower eccentric bush, with a slot provided between the upper and lower eccentric bushes. A locking pin functions to change a position of the upper or lower eccentric bush to a maximum eccentric position. Further, upper and lower brake units are respectively provided between the upper eccentric cam and the upper eccentric bush, and between the lower eccentric cam and the lower eccentric bush.

Abstract: A variable capacity rotary compressor including a housing to define therein two compression chambers having different capacities, a rotating shaft transmit ting a rotating force from a drive unit to the two compression chambers, two eccentric parts are provided on an outer surface of the rotating shaft to be placed in the two compression chambers, respectively. Two eccentric bushes, having different weights respectively fitted over the eccentric parts to rotate relative to the rotating shaft within predetermined angles, a pair of force transmission parts, provided on opposite sides of the eccentric unit, to receive the rotating force of the rotating shaft so that one of the two eccentric bushes rotates while being eccentric from the rotating shaft and a remaining one of the two eccentric bushes rotates while being released from eccentricity from the rotating shaft, according to a rotating direction of the rotating shaft.

Abstract: The invention is a device and method in a high-pressure chromatography system, such as a supercritical fluid chromatography (SFC) system, that uses a pump as a pressure source for precision pumping of a compressible fluid. The preferred exemplary embodiment comprises a pressure regulation assembly installed downstream from a compressible fluid pump but prior to combining the compressible flow with a relatively incompressible modifier flow stream. The present invention allows the replacement of an high-grade SFC pump in the compressible fluid flow stream with an inexpensive and imprecise pump. The imprecise pump becomes capable of moving the compressible fluid flow stream in a precise flow rate and pattern. The assembly dampens the damaging effects of an imprecise pump, such as large pressure oscillations caused by flow ripples and noisy pressure signals that do not meet precise SFC pumping requirements.

Abstract: A variable capacity rotary compressor is designed to make a pressure of a high-pressure side be uniformly applied to upper and lower ends of a roller of a low-pressure side, allowing the roller of the low-pressure side to be smoothly rotated. The compressor includes a housing to define two compression chambers which are partitioned by a partition plate. Two flanges are mounted to predetermined positions of the compression chambers to close openings of the compression chambers. A rotating shaft passes through the compression chambers and the partition plate. Two eccentric units are mounted to the rotating shaft to be placed in the compression chambers. One of the eccentric units is eccentric from the rotating shaft to execute a compression operation while a remaining one of the eccentric units is released from eccentricity from the rotating shaft to execute an idle rotation, according to a rotating direction of the rotating shaft.

Abstract: A variable capacity rotary compressor, which is designed to make an internal pressure of a compression chamber, where an idle rotation is executed, be equal to an outlet side pressure of the rotary compressor, thus minimizing a rotating resistance. The compressor includes a housing partitioned into two compression chambers having different capacities by a partition plate. A rotating shaft rotates in the compression chambers. Two eccentric units are mounted to the rotating shaft to be placed in the compression chambers, and execute a compression rotation and an idle rotation according to a rotating direction of the rotating shaft. A pressure control unit functions to apply the pressure of the outlet side of the compressor to the compression chamber which executes the idle rotation. The pressure control unit includes a path control channel which is vertically provided through the partition plate to be placed at a position outside the compression chambers.

Abstract: Disclosed are an air conditioning system with two compressors and a method for operating the same, so as to variably change a compression capacity of a refrigerant according to the variation of cooling load. Herein, when a full operation order is inputted to the two compressors in order to satisfy increased cooling load, the first compressor is first operated, and then the second compressor having a compression capacity of a refrigerant smaller than that of the first compressor is additionally operated, so that a current peak value for operating the compressors does not exceed an allowable current range of a circuit breaker installed in a home or building, thereby safely controlling the air conditioning system and simultaneously allowing the current to be provided to other electric appliances, thus improving users' convenience.

Abstract: The present invention relates to a circuit for controlling a discharge amount of a hydraulic pump which is capable of constantly supplying a discharge amount of a hydraulic pump to an actuator irrespective of a load pressure of the actuator even when an engine operates at a low speed, wherein the circuit comprises a variable displacement hydraulic pump connected with an engine; an actuator connected with the hydraulic pump; a center bypass type directional switching valve installed in a flow path between the hydraulic pump and the actuator for controlling a start, stop and directional switching of the actuator during a switching operation; a pilot signal generating means installed in a down stream side of a center bypass path of the directional switching valve for controlling a discharge amount of the hydraulic pump; and a discharge amount adjusting valve which is installed in a supply path of the actuator of the center bypass type directional switching valve for controlling a discharge amount of hydraulic fl

Abstract: A variable capacity rotary compressor, which precisely controls variation of a compression capability into a desired discharge pressure, and which minimizes a resistance to rotation of a rotating shaft, and thus improves the capacity of the rotary compressor.

Abstract: The invention relates to a hydraulic system (1) comprising a main pump (12) and a precompression pump (5), whereby the outlet (8) of the precompression pump (5) is connected by a connecting line (9) to the inlet (11) of the main pump (12). The outlet (16) of the main pump (12) can be connected by a working line (17) to a consumer (A, B). The volume flow at the inlet (11) of the main pump (12) is changeable. The aim of the invention is to achieve greater efficiency. The precompression pump (5) comprises an adjusting device (6) for adjusting the flow rate.

Abstract: A first bypass valve (27) that sets discharge capacity to 60% is provided in a first scroll 21 of an asymmetrical spiral-type scroll compressor. Also, a second bypass valve (40) that makes suction side and discharge side communicated with each other so that set load of the compressor becomes 50% is provided outside a scroll of the first scroll (21). In this way, by closing the first and second bypass valves (27, 40), effective load of the compressor is set to 100%. Also, by opening the first bypass valve (27) and concurrently closing the second bypass valve (40), the effective load of the compressor is set to 60%. Further, by opening both the first and second bypass valves (27, 40), the effective load of the compressor is set to 30%.

Abstract: A method and apparatus are provided for continuously dispensing precise quantities of a liquid from a dispenser holding tank into a receiving tank. A first elastic tube permits fluid flow between the holding tank and the receiving tank and a first peristaltic pump controls the flow rate of liquid through the first elastic tube. A second elastic tube permits fluid flow between the holding tank and the receiving tank and a second peristaltic pump controls the flow rate of liquid through the second elastic tube. The flow rates through the first and second elastic tubes are independently controlled. The flow rate through the first elastic tube is maintained generally constant and at a substantially greater rate than the flow rate of the second elastic tube. The flow rate in the second elastic tube is varied to maintain a desired total flow rate into the receiving tank.

Abstract: A compressor protection and control subsystem for a rotary compressor provides temperature pressure, mis-wiring and vibrational protection for the scroll machine. The vibrational protection comprises a vibration sensor which is integrated on the circuit board of the protection and control subsystem. The vibration sensor, in conjunction with at least one timer, monitors the vibrations of the scroll machine and will shut down the machine when excess vibrations are sensed over a prespecified period of time. The temperature system monitors operating temperature conditions the pressure system monitors operating pressures and the mis-wiring system monitors the power supplied to the compressor. Once an undesirable characteristic is identified, the operation of the scroll machine is stopped. These protection systems are integrated into a single subsystem which identifies the reason of shutting off the scroll machine in order to simplify repairs needed.

Abstract: The invention relates to an oil pump for an internal combustion engine with at least one pair of toothed wheels which are in mutual engagement, at least one intake port and at least one outlet port. An improved supply of oil at reduced driving power can be achieved with at least two pairs of toothed wheels; a first common shaft, which a first toothed wheel of each pair of toothed wheels is arranged, and means are provided to charge the individual pairs of toothed wheels with oil depending on the required quantity of conveyed oil.

Abstract: A pump which can operate in a number of different modes, wherein each mode corresponds to a different output of the pump. The pump may have a plurality of pump chambers located within a pump housing. The pump chambers may be arranged in fluid communication with an inlet port and an outlet port. Each pump chamber may have a pumping device which draws in fluid from the inlet port during an intake stroke and pushes fluid through the outlet port during a discharge stroke. The pump may also have a plurality of electronically controlled valve assemblies which control the output of the pump. Each valve assembly can be selectively switched to a by-pass state for by-passing the fluid flowing from the pump chamber back to the inlet port during the discharge stroke of a pumping device. The pump may operate in a number of different modes which each have a distinct output. Each mode may be defined by which valves are chosen to be switched to their by-pass state.

Abstract: A total power regulation device for a plurality of variable displacement pumps (1, 2), each having a regulation valve (18) which regulates its displacement volume, which is acted upon--against a counter-pressure--by a control pressure corresponding to the working pressure of the variable displacement pump. When the control pressure exceeds the counter-pressure, the regulation valve regulates the variable displacement pump along a characteristic line (KL) of constant torque. To adjust the desired values of the individual drive torques simply, and to prevent torques from exceeding a desired value, an electronic control unit (16)--connected to measuring detectors (25) for detecting the displacement volumes of the variable displacement pumps--stores the desired value totals of the counter-pressures and the torque characteristic lines (KL) of the variable displacement pumps, and has a desired value setting device (27) for dividing the desired value total.

Abstract: A multicylinder rotary compressor capable of performing high performance capacity control operation without the need for an external piping or for a thicker partition plate which leads to a taller rotary compressing element or a longer bearing span of a bearing. The multicylinder rotary compressor has a rotary compressing element housed in a hermetic enclosure; wherein the rotary compressing element is equipped with an intermediate partition plate, a cylinder provided on each side of the partition plate, a rotary shaft having eccentric sections which are shifted relative to each other by 180 degrees in the direction of shaft rotation, rollers fitted onto the eccentric sections of the rotary shaft and which rotate in the cylinders, and bearings which seal the cylinders.

Abstract: The present invention relates to an oil supply system with at least one pressure and/or volume dependent controllable pump (1) and an oil tank (5) or the like from which the pump draws oil and delivers it with controlled output pressure or output volume to a system (8) to be supplied.

Abstract: An energy-efficient refrigeration system includes a dual cylinder compressor and a compressor controller coupled to the compressor to control compressor capacity by selection of a predetermined refrigerant flow path through the compressor. The dual cylinder compressor includes first and second cylinders with respective first and second pistons that are horizontally opposed and coupled together by a fixed and non-pivoting connecting rod. The void volume of one cylinder is typically greater than the void volume of the other cylinder, and the compressor typically is a scotch-yoke drive apparatus or, alternatively, a linear voice coil drive apparatus.