Abstract: A compressor having an internal refrigerant gas passage selectively connected to and disconnected from an external refrigerant circuit separately provided from the compressor is described. The compressor has a plurality of pistons reciprocable in a plurality of cylinder bores in a housing for compressing gas supplied from the external refrigerant circuit to the internal refrigerant gas passage. A drive shaft is rotatably supported by the housing. A swash plate is supported on the drive shaft for integral rotation with inclining motion with respect to the drive shaft. The swash plate is movable between a maximum inclined angle and a minimum inclined angle. The disconnecting device disconnects the internal refrigerant gas passage from the external refrigerant circuit when the swash plate is at the minimum inclined angle. The internal refrigerant gas passage includes a first passage which connects a crank chamber and a suction chamber to deliver the refrigerant gas from the crank chamber to the suction chamber.

Abstract: The oil sump and suction plenum of a hermetic compressor are in continuous fluid communication through an oil equalization port assembly. Additionally, communication is established between the oil sump and the suction plenum if pressure in the oil sump is greater than that in the suction plenum by more than a few pounds. Multiplexing is established through a port in the suction plenum.

Abstract: A swash plate type compressor is connected with an external refrigerant gas circuit. A device accommodated in the compressor disconnects the external circuit with the suction chamber when the swash plate is at the minimum inclining angle. A pressure decreasing passage creates the connection between the crank chamber and the suction chamber to decrease the pressure in the crank chamber. This passage releases the pressure in the crank chamber to the suction chamber when the pressure in the crank chamber is greater than the pressure in the suction chamber so that the swash plate is inclined toward the maximum inclining angle. An adjusting device adjusts the pressure in the pressure decreasing passage so that the pressure decreasing passage is opened to a greater degree when the swash plate is at the maximum inclining angle than when the swash plate is between the maximum and minimum inclining angles.

Abstract: A compressor has a refrigerant gas passage selectively connected to and disconnected from a refrigerant circuit separately provided from the compressor. The compressor has a plurality of pistons reciprocable in a housing for compressing refrigerant gas. A drive shaft is rotatably supported by the housing. A swash plate is supported on the drive shaft for integral rotation with inclining motion with respect to the drive shaft to drive the pistons. The swash plate is movable between a maximum inclined angle and a minimum inclined angle. A disconnecting member disconnects the refrigerant circuit from the refrigerant gas passage when the swash plate is at the minimum inclined angle. A bleed hole bleeds the refrigerant gas from the refrigerant gas passage to the refrigerant circuit to suppress rapid increase of the inclined angle when the disconnecting member operates.

Abstract: A scroll type refrigerant compressor having an axial housing means defining a discharge chamber and a low pressure chamber around the discharge chamber, a stationary scroll , and a movable scroll. The movable scroll engages the stationary scroll and moves along a predetermined orbiting path respective to the stationary scroll. The stationary and movable scrolls define compression chambers therebetween. The stationary end plate of the stationary scroll includes a pair of relief ports for fluid communication between the compression chamber and the low pressure chamber. The compressor further comprises a valve plate in the form of a ring with a pair of valve ports. The valve plate is rotatable about the axis of the compressor between an open position where the valve port is aligned with the relief port to provide fluid communication between the compression chambers and the low pressure chamber and a closed position where the valve port separates the compression chamber from the low pressure chamber.

Abstract: A variable capacity vane compressor uses a linear actuator. The linear actuator is pivotally connected to a valve plate to rotate the valve plate between minimum delivery and maximum delivery positions. The actuator has springs on each end which bias the actuator to an equilibrium position between the full and minimum delivery positions for start up. Control pressure is supplied to one side of the actuator while the other side of the actuator is at intake pressure.

Abstract: An apparatus for electronically controlling the flow of low pressure gas to a compressor and preventing backflow from the compressor, the apparatus including a housing in fluid communication with the compressor, where the housing has a chamber, a housing inlet for receiving a low pressure gas, and a housing discharge port for flowing the low pressure gas to the compressor and through which backflow gas flows from the compressor. A valve member having a contact end is movable within the chamber along a predetermined path. The apparatus also includes a drive for moving an actuator along an axis. The actuator has an extension with an end adapted to abut the contact end of the valve member to thereby move the valve member along the path toward the housing inlet. The valve member is movable along the path and away from the inlet, when the actuator is retracted, by the flow of low pressure gas through the inlet.

Abstract: An induction regulator valve is incorporated in the induction manifold of a compressor to provide for infinitely variable regulation of the output from the rotary type compressor, in particular the screw-type compressor. The closing piece of the induction regulator valve can be adjusted by means of an actuator system. To improve this regulation performance of this system, in particular to reduce its sensitivity when the regulator valve is almost closed, the spring system is formed so that its stiffness varies along the length of its spring path, the stiffness of the spring system being smaller when the induction regulator valve is open than when it approaches the closed position of the closing piece of the induction regulator valve.

Abstract: A control valve for a variable rotary vane compressor is modular. The control operates an actuator to vary the position of a rotary valve plate located between the intake chamber and the compression chamber. The control valve locates in a cavity which has a suction pressure portion, a control pressure portion, and a discharge pressure portion. The control valve has an end cap and a valve seat member connected together by a sleeve. A valve element engages a seat in the valve seat member. The spring and a bias pin urge the valve element to the closed position. A bellows located within the sleeve has a stem that contacts the valve element to move it off of the seat. The sleeve allows the distance between the valve seat member and the end cap to be varied to preset the bellows prior to installation in the compressor.

Abstract: A compressor has an air inlet valve for controlling air intake when demand for service air from the compressor changes. The valve has a housing with an inlet and an outlet which is connected to a compressor. A rod in the housing is movable relative to the housing and has a shoulder and a piston. A movable valve member is mounted on the rod and a spring is interposed between the piston and the housing for moving the shoulder into engagement with the valve member and biasing the valve member toward the closed position. The housing has a chamber on each side of the piston for receiving air that discharges from the compressor. Air pressure is connected to one of the chambers to move the valve member toward the closed position when the pressure of air in the receiver tank exceeds a set-point.

Abstract: An intake control valve for a screw-type compressor is built into the intake line, which it alternatingly opens or closes. The intake control valve, designed as a double seat valve, has a locking body (17), to which are assigned two opposing valve seats, namely a return flow seat (7) and an intake seat (9). Upon starting the screw-type compressor, the locking body (17) is pulled onto the intake seat (9) by means of the resulting intake pressure. As soon as a specific operating pressure is reached, the locking body (17) is lifted from the intake seat (9) by means of the pressure medium by way of a control cylinder (10) with a control piston (11) and moved into an intermediate position between its two seats (7, 9), so that the screw-type compressor can totally transport.

Abstract: A start control for a compressor has an air inlet valve for reducing flow intake when a compressor is started. The valve has a housing with an inlet and an outlet which is connected to a compressor. A rod in the housing is movable relative to the housing and has a shoulder and a piston. A movable plate is mounted on the rod and a spring is interposed between the plate and the housing for biasing the plate toward a closed position in which the housing inlet is at least partially closed. A second spring is interposed between the piston and the housing for moving the shoulder into engagement with the plate and biasing the plate toward the closed position. The housing has a chamber on each side of the piston for receiving air that discharges from the compressor. Air pressure applied to one side of the piston assists the first spring and the second spring move the plate toward the closed position when the compressor is in a start mode of operation.

Abstract: An electronically controlled gas compressor inlet valve includes a housing mounted on the compressor in fluid communication with an inlet of the compressor. A piston member is moveable linearly within the housing along a path of travel, into and out of occluding relation with the compressor inlet. A linear positioning device is connected to the piston member. The linear positioning device positions the piston member linearly, in a predetermined location, along the path of travel. A vent maintains a predetermined atmospheric pressure across the piston member. A sensor determines compressor inlet pressure, and generates a signal in response to a predetermined inlet pressure. A controller is operatively connected to the stepper motor for controlling actuation of the stepper motor in response to the signal generated by the sensor.

Abstract: A hydraulic pressure system includes a pump and a dry valve situated in the inlet of the pump, the dry valve being actuated by a pilot valve capable of capturing the pressure differentials between inlet and outlet of the pump for shifting the dry valve between opened and closed positions. In the dry operational mode, the pump inlet operates at a pressure below atmospheric, thus providing a pressure differential substantial enough to move the dry valve to an opened position. In the preferred form, the pilot valve is a solenoid actuated two-position, four-way, spring loaded valve. The dry valve is a gate valve directly coupled to a fluid control motor.

Abstract: A variable capacity vane compressor has an axial pressure device for applying variable axial pressure to a rotary valve. The rotary valve plate locates in a rotary valve housing and changes the capacity of the compressor due to its rotary position. An actuator member rotates the rotary valve plate in response to varying pressure in the discharge and intake chambers. A control valve supplies a variable control pressure to the actuating member for moving the actuating member to rotate the rotary valve plate. An annular axial pressure chamber is located between the rotary valve housing and the rotary valve plate. A control pressure port leads from the control valve to the axial pressure chamber. A seal member within the axial pressure chamber applies an axial force on a bearing located on the rotary valve plate. The control valve which supplies variable pressure used to vary the actuator member position also supplies the control pressure to the axial pressure chamber.

Abstract: An oil-free scroll compressor comprising a plurality of oil-free scroll compressing mechanism blocks, each for compressing a gas, and a motor or motors for driving the plurality of oil-free scroll compressing mechanism blocks. In operation, an air is suctioned into the compressor through a filter and a throttle valve and then divided and sucked into first and second oil-free scroll compressing mechanism blocks, which act to increase the pressure of the air to a predetermined pressure. The compressed air is cooled by an after-cooler and supplied to the compressed air user side. The scroll compressing mechanism blocks are driven by a dual-shaft motor through belts. Under no-load condition, the throttle valve is closed and a release valve is opened, whereby the compressed air held between the blocks and check valves is released.

Abstract: An apparatus for regulating the fluid throughput of a rotary screw compressor from a full capacity operating condition to a desired predetermined capacity operating condition includes a turn valve or spiral valve which is disposed in fluid communication with a low pressure fluid. A stepping motor positions the turn valve in a predetermined orientation. A position sensing means is operably connected to the turn valve. The position sensing means detects the angular orientation of the turn valve. A pressure sensing means detects a compressor service pressure. An electronic control means directs the stepping motor in a predetermined orientation. The electronic control means is independently operable to regulate the fluid throughput of the rotary screw compressor from a full capacity operating condition to a predetermined capacity operating condition in response to the first pressure sensing means.

Abstract: An apparatus for regulating a compressor lubrication system includes an oil-flooded rotary gas compressor, a reservoir flow connected to the compressor, a heat exchanger for cooling a lubricant, and a controller. A thermal mixing valve regulates the temperature of the lubricant flowing to the compressor. A first temperature sensor measures a discharge temperature at a compressor outlet, and provides a signal corresponding to the discharge temperature to the controller. A second temperature sensor measures a lubricant temperature at a lubricant inlet to the compressor, and provides a signal corresponding to the lubricant temperature to the controller. A pressure sensor measures the pressure at the outlet of the compressor, and provides a corresponding pressure signal to the controller. A valve means continuously regulates the supply of lubricant to the compressor, the valve means being controlled by the controller in response to the temperature signal of the first temperature sensor and the pressure signal.

Abstract: The present invention provides a check valve which, when placed at the end of a pump suction pipe, allows the pump to draw fluid therethrough from a continuously replenished, below-ground fluid source. When the fluid in the fluid source has been depleted to a level below that which allows fluid to be drawn therefrom by the pump, the present check valve maintains the suction pipe full of fluid. The check valve also maintains the suction pipe full of fluid when the pump has been shut off. In this manner, the pump can resume drawing fluid from the fluid source without the need for priming.

Abstract: The discharge flow from a rotary vane pump is metered by directing a portion of the pump discharge back into the pump inlet area. A servo controlled actuator apportions the relative amounts of inlet fluid and returns fluid which enters the vane cavities. This arrangement allows for the use of a fixed cam which provides improved pump performance as compared to comparable movable cam pump designs.

Abstract: A screw vacuum pump is capable of reducing the load thereon at the time of evacuation of a gas at atmospheric pressure by the use of a throttle plate. The screw vacuum pump has male and female rotors which rotate in meshing engagement with each other around two parallel axes, respectively, in a casing so that a gas that is sucked in from a suction opening is introduced through a suction port into a groove space defined between the male and female rotors and the casing is then discharged from a discharge opening through a discharge port, wherein the throttle plate is provided upstream of and near the opening of the suction port.

Abstract: A Roots-type machine is connected to an enclosure to be evacuated via a suction inlet portion, and to a primary pump via a delivery outlet portion. A bellows is disposed transversely in the inlet portion, one end of the bellows being fixed in gastight manner in the wall, and the other end being closed and movable, so that the bellows forms a regulating member for regulating the gas-flow sectional area in the inlet portion. The outside face of the movable end of the bellows is subjected to the pressure in the inlet portion, and the inside face of the movable end is subjected to the pressure in the delivery outlet portion via a rod passing through the wall, and via a channel. The invention applies to Roots-type machines, in particular for automatically regulating the pumping speed so as to match it to the flow-rate of the corresponding primary pump.

Abstract: A variable capacity vane compressor includes a bearing arrangement having a radial bearing radially supporting a drive shaft of the compressor, and a thrust bearing rotatably supporting a capacity control element. The bearing arrangement comprises an annular member fixed in a through hole formed through a side block of the compressor, through which the drive shaft extends. The annular member has an inner peripheral surface in which the radial and thrust bearings are received. The annular member is formed of a material having a coefficient of thermal expansion substantially equal to that of a material forming the radial bearing. The thrust bearing has a first race disposed on a side thereof close to a rotor of the compressor, and a second race disposed on a side remote from the rotor. The first race is force-fitted in a through hole formed through the capacity control element and slidably fitted in the inner peripheral surface of the annular member.

Abstract: An improved rotary-type vacuum pump includes a lubrication circuit in which an oil inlet port of an oil suction duct is directed towards the floor of the pump casing, rotors having oil spaces filled with oil between the vanes, an oil filter provided at the outside of the pump housing, and an excess pressure discharge valve immersed in the oil and being disposed at a terminating portion of the lubrication circuit. The mounting of other essential elements of the pump unit is concentrated on the front cover and the pump housing of the pump.

Abstract: A hydraulic pump of the rotary vane type comprises a first throttle bore and a second throttle bore disposed in parallel between a pressure chamber of the pump and a delivery passage, and a variable flow throttle valve is provided which is responsive to a difference between a vane back-up pressure and a pressure within the delivery passage to vary an opening degree of the first throttle bore.

Abstract: In a compressor having an oil sump located therein, a restricted communication is provided between the oil sump and the suction plenum. As a result, froth generation due to a rapid pressure drop in the oil sump is reduced. A relief valve is provided to limit the pressure differential between the suction plenum and the oil sump.

Abstract: A variable capacity compressor comprises a control element for determining the timing of start of compression of refrigerant gas. Control pressure which acts on the control element to displace same between the minimum capacity position and the maximum capacity position is created in a high-pressure chamber by introducing discharge pressure thereinto. An electromagnetic valve opens and closes a passageway which commincates between the high-pressure chamber and a suction chamber by a pulse signal supplied from an ECU to control an amount of refrigerant gas leaking from the former into the latter to thereby control the level of the control pressure. The ECU makes the width of at least a first pulse or at least a first pulse base of the pulse signal wider than that of the following pulses or pulse bases, when the control element should start to be displaced between the minimum capacity position and the maximum capacity position.

Abstract: A fluid flow control system maintains a constant, controllable, low flow rate through an orifice; intermittently operates a pump at an efficient, relatively high flow rate; and moderates flow between the pump and the orifice. The system is energy efficient and accurate.

Abstract: To enable the prevention of smearing an equipment and its periphery with lubricating oil, the alleviation of a burden in maintenance of the equipment by reducing a decrement of the lubricating oil, and the lowering of running cost, an oil-cooled compressor has a suction control valve 5 in a suction passage 3 and an air discharge valve 9 in a discharge passage 6 in a compressor body 1. An oil discharge passage 16 is formed for leading outside the lubricating oil supplied to bearing and shaft seal sections of the compressor body 1, an oil return passage 17 communicating with the inlet side of the suction control valve 5, an oil reservoir section 18 located between the oil discharge passage 16 and the oil return passage 17, and an air discharge passage 19 arranged with one end connected to the outlet port of the air discharge valve 9 and its another end reaching the oil reservoir section 18.

Abstract: In a non-clutch compressor, by controlling a differential pressure between a crank chamber accommodating an oscillating plate therein and a cylinder chamber in a suction stroke, an incline angle of the oscillating plate is sequentially changed so that a maximum stroke of a piston is changeable. The compressor includes a passage opening and closing device arranged at an inlet section of one of a suction pipe connecting with a suction chamber of the compressor and the suction chamber, and a pressure control valve arranged between a discharge chamber and the crank chamber, the valve opening in a case where pressure in the suction chamber is less than a set value. In the compressor, a cross-sectional area (A) of a passage of a discharge hole for connecting the crank chamber with the suction chamber is expressed by an equation: 0.5<(A)<1.8 mm.sup.2.

Abstract: This invention relates to a radial piston pump in whose suction bore (22) a load regulator (24) is inserted. The pump is to be regulated so that a constant stream and, as required, a variable large regulating stream will be available. For this purpose, a spool valve (26) that can be activated electromagnetically is inserted in a bore (23) that intersects the suction bore (22) and that spool valve can establish a connection to a suction duct (28) that is connected to a cam chamber (14) to make the regulating stream available by means of a collar (33). From suction bore (22) there furthermore branches off a shutter bore (34) that is likewise connected to the cam chamber (14) via a ring groove (35) and additional bores (36) in the pump housing (3). Shutter bore (34) limits the constant stream. The regulating stream is supplied to a consumer with fluctuating power consumption, for example, a hydrofan, that is powered with an rpm proportional to the cooling water temperature.

Abstract: A variable capacity vane compressor has a thrust bearing received in an annular recess formed in the inner peripheral surface of a through hole of a side block through which a drive shaft extends. The thrust bearing axially supports a capacity control element for controlling timing of start of compression of refrigerant gas. An annular member is force-fitted in the annular recess to urge one race of the thrust bearing against the side block. Another race of the thrust bearing is slidably fitted in the inner peripheral surface of the annular member. This race is force-fitted in a hole of the capacity control element through which the drive shaft extends. The inner peripheral surfaces of the two races are spaced from the outer peripheral surface of the drive shaft.

Abstract: A device and method are shown for controlling tank vapors on a petroleum storage tank of the type having a tank vapor line which runs to a suction scrubber. The scrubber being connected by conduit to a reciprocating compressor which, in turn, is connected to a compressed vapor discharge line for passing compressed vapors to a gas sales line. The reciprocating compressor is operated to draw tank vapor through the suction scrubber and through the reciprocating compressor to discharge vapor through the compressed vapor discharge line. A pneumatic control valve is installed in the tank vapor line for controlling the flow of tank vapors to the suction scrubber. A pilot valve is provided as a part of the pneumatic control valve for controlling the operation of the control valve. The control valve is operated to maintain a vacuum in the tank vapor line between the control valve and the suction scrubber to eliminate the tendency of tank vapor to liquify in the tank vapor line.

Abstract: Device for controlling the pressure in a hydraulic pressure system in which the output of a constantly running pump which feeds pressure medium to a pressure system is controlled by means of a suction throttle valve which itself is actuated as a function of the pressure in the pressure system of the vacuum in the connection between pump and suction throttle valve.An over pressure in the pump output acts to close the throttle valve, while under vacuum in the pump outlet acts to open the throttle valve, thus allowing for a two point control without additional control valves.

Abstract: A variable capacity vane compressor has a control element for determining timing of start of compression of a refrigerant gas. In a high-pressure chamber there prevails control pressure which acts on the control element for urging same toward a maximum capacity position thereof. The control pressure is created by introducing the refrigerant gas from a discharging space within which discharge pressure prevails into the high-pressure chamber via a high pressure-introducing passageway. The high pressure-introducing passageway has a restriction hole for restricting flow of the refrigerant gas. An electromagnetic value opens and closes the restriction hole in response to an external control signal. The refrigerant gas is allowed to constantly leak from the high-pressure chamber into a suction chamber via a leak passage, the leak passage having a cross-sectional area smaller than that of the restriction hole.

Abstract: A variable-delivery vane-type rotary compressor including receiving means for defining a space for rotatably receiving a disc-shaped rotary closure member, which is associated with one of the end openings of a by-pass passage, within the end wall of a compression chamber. The receiving means may also be provided on the peripheral wall of the compression chamber. The bearing means is provided between the rotary closure member and the end wall of the compression chamber.

Abstract: In accordance with the present invention there is provided a hydraulic drive assembly including a driven member having a hydraulic pump located therein for selectively circulating liquids within the driven member, a drive shaft connected to the driven member for turning the drive shaft of the hydraulic pump, and a control member for selectively varying the flow of fluids from the pump.

Abstract: A surging prediction device for a centrifugal compressor has a differential pressure detector and a controller. The detector detects a differential pressure between a hub side pressure in the vicinity of an inlet or a diffuser in the centrifugal compressor and a shroud side presser in the vicinity of the inlet of the diffuser. The controller compares the detected differential pressure from the detector with a set differential pressure beforehand set so as to be lower than a surging differential pressure between the hub side pressure and the shroud side pressure at an occurrence time of surging, and outputs a surging signal predicting an occurrence of surging when the detected differential pressure becomes higher than the set differential pressure.

Abstract: A vane compressor includes a cylinder having a pair of side blocks. A communication passage is formed through at least one of the side blocks. The communication passage has one end thereof opening into a discharge pressure chamber, and another end thereof opening in a rotor side end face of the at least one of the side blocks at a location corresponding to the orbital path of an end of a back pressure chamber defined in each of vane slits having a vane slidably fitted therein. The communication passage is provided therein with a valve which opens the communication passage when the difference between pressure in the discharge pressure chamber and pressure in the back pressure chamber is below a predetermined value, and closes same when the difference in pressure is above the predetermined valve.

Abstract: A variable capacity vane compressor has a first oil sump formed in a bottom of a discharge pressure chamber arranged at one side of a cylinder close to one side block, and a second oil sump formed in a bottom of a suction chamber arranged at another side of the cylinder close to the other side block. An oil passageway communicates between the first oil sump and the second oil sump. A control element is arranged in the other side block for rotation about its own axis in opposite directions to thereby vary the compression starting timing. A pressure chamber acts to apply control pressure created from discharge pressure from the cylinder to the control element for causing rotation of the control element. A seal member is fitted on the control element such that part of the seal member is located in the pressure chamber. A high pressure-introducing passageway is formed in the other side block and communicates with the second oil sump.

Abstract: In a scroll type of compressor having a stationary scroll, a movable scroll opposed to the stationary scroll and rotatable thereabout but not rotatable about its own axis, so that a closed chamber which decreases in volume during the rotation of the movable scroll is defined by and between the stationary scroll and the movable scroll, and an introduction passage through which a coolant is introduced into the compressor, wherein a capacity varying apparatus comprises a suction restriction mechanism provided in the introduction passage to control the cross sectional area thereof in accordance with the pressure of the coolant, a by-pass passage extending through the stationary scroll to connect the portion of the closed chamber connected to start ends of scroll portions provided on the movable and stationary scrolls, while being reduced in volume, to suction pressure area in the compressor, a by-pass opening and closing mechanism provided in the by-pass passage to open and close the latter in accordance with the

Abstract: A variable capacity vane compressor has a control element rotatable in response to the difference between suction pressure and control pressure for varying the compression starting timing and hence the capacity. A communication passage extends between the suction chamber and a high pressure chamber in which the control pressure is created. A spool valve opens and closes the communicating passage. An electromagnetic actuator generates an electromagnetic force to cause the spool valve to open the communication passage when energized. A control unit is arranged outside of the compressor and supplies the actuator with an external control signal for energizing the actuator.

Abstract: A compressor coupled to a load of smaller capacity is provided for loading with a setpoint adjusting circuit substituting a pseudo-setpoint signal for the pressure signal derived from the load, so that the master-controller operates in response to a signal increasing gradually from a low initial value until matching in magnitude with the assigned setpoint signal for normal operation. The master-controller is modified so as to bypass the normal modulation means during loading, a minimum inlet valve opening being imposed initially and concurrently the bypass valve being allowed to close under the low initial value, inlet valve control being enabled after the bypass valve has closed and in accordance with said gradual increase of the pseudo-setpoint signal. After load pressure has reached the assigned pressure setpoint in magnitude, the master-controller normal operation is reinstated.

Abstract: A compressor suitable for use in a vehicle cooling system. The compressor includes a cylinder having a cylindrical inner wall surface, a rotor supported by a crankshaft having an eccentric portion in the cylinder. A pair of vanes are carried at diametrically opposed positions by the rotor to extend in a radial direction, each of the vanes having a radially outward edge which is in sliding contact with the inner wall surface of the cylinder. End plates are secured to the cylinder at the axially opposite ends of the cylinder. A link mechanism is provided between the rotor and at least one of the end plates so that the rotor conducts a reciprocating angular movement in an angular range in response to a rotation of the crankshaft. The inner wall surface of the cylinder, the vanes and the end plates define working chambers of which volumes are variable in response to the angular movement of the rotor.

Abstract: A variable capacity vane compressor in which one end face of a side block facing the rotor is formed therein with an annular recess in a bottom of which is formed a second recess. A control element rotatably received in the annular recess for varying the timing of commencement of the compressor. The control element cooperates with the second recess to define therebetween a pressure working space. The control element has a pressure-receiving protuberance slidably fitted in the pressure working space to divide same into a first pressure chamber and a second pressure chamber. A communication passage extends between the first pressure chamber and a low pressure zone. A control valve device is arranged in the communication passage for opening and closing the communication passage in response to suction pressure. A sealing device is provided in the bottom of the annular recess and engages portions of the control element other than the pressure-receiving protuberance.

Abstract: A vane compressor has at least one compression space defined between a rotor and a cylinder. A shaft seal and a bearing are fitted on a driving shaft and disposed adjacent to each other. A lubricating oil supply device supplies compression medium to the shaft seal and the bearing, through at least one passage extending between the at least one compression space and the shaft seal and the bearing. The at least one passage has an open end opening into the at least one compression space at a predetermined circumferential location at which pressure within the at least one compression space changes from a negative value into a positive value when each of the vanes passes the predetermined circumferential location, whereby lubrication and cooling of the shaft seal and the bearing is effected in an efficient manner.

Abstract: An anti-return safety apparatus for an installation comprising a vacuum vessel connected to a vacuum pump having an oil seal, wherein the apparatus comprises a valve constituted by a rigid tube having a flexible tube situated therein with the two ends of the flexible tube being fixed in sealed manner to the ends of the rigid tube, a control orifice being provided through the wall of the rigid tube in the vicinity of the middle thereof, the valve being connected between the vessel and the suction inlet to the pump, and in that a slide valve suitable for establishing two different communication paths is provided suitable for establishing a connection between a common outlet C and one or other of two distinct inlets a, and b, the common outlet C being connected to the control orifice of the valve having the flexible tube, the inlet a being connected to the suction inlet of the pump, and the inlet b being opened to atmospheric pressure, the slide valve being electromagnetically controlled by a coil, itself contro

Abstract: In a compressor control system, a subcontroller is coupled with the master-controller in order to detect, when the bypass valve is being modulated, whether there is a deviation between the minimum inlet valve position assigned to the system and the actual inlet valve position. In such case, correction of the inlet valve position is automatically effected by the subcontroller in either direction to restore the minimum assigned inlet valve position.

Abstract: A variable-delivery vane-type rotary compressor including receiving means for defining a space for rotatably receiving a disc-shaped rotary closure member, which is associated with one of the end openings of a by-pass passage, within the end wall of a compression chamber. The receiving means may also be provided on the peripheral wall of the compression chamber. The bearing means is provided between the rotary closure member and the end wall of the compression chamber.

Abstract: A hydraulic system is provided including a hydraulic pump which is continuously coupled with the engine of a utility such as a dump truck utilized for snow-ice removal. When hydraulic implements employed on the truck are not actuated, the pump operates in a cavitation mode. During this cavitation mode of operation, there is no ingress of air through seals or the like to a venting of the gear pump chamber essentially to tank or atmosphere. A poppet valve is actuated in conjunction with periodic use of hydraulic elements on the truck to actuate the pump to an operational or pressurized mode. A key actuated calibrating system is employed to calibrate snow-ice removal components in a secure manner. Calibration is provided in conjunction with EEPROM memory.