Abstract: A winding circuit for use in a fan includes first and second integrated circuits that each include a transistor for powering first and second fan windings in the fan, and at least one of a thermal shutdown element that switches the winding circuit "off" if the integrated circuit reaches a predetermined temperature, and a current regulating circuit. The fan includes a rotor having a magnet, and a stator having a magnet sensor to alternatively transmit current to the first and second windings, which also are located in the stator. The integrated circuits may be autoprotected MOSFETs and the magnet sensor may be a Hall effect sensor.

Abstract: A fluid pump includes main support bearings for supporting the impeller shaft and back-up bearings for supporting the shaft upon failure of the main support bearings. The back-up bearings are positioned between the main support bearings and shaft driver/motor, and have a radial clearance with the shaft which is greater than the radial clearance between the main support bearings and shaft and yet is small enough to prevent any shards that may result from failure of the main support bearings from passing through the radial clearance space between the back-up bearings and shaft and damaging other rotating parts of the pump. A diagnostic monitor detects wear or failure of the main support bearings by sensing relative shaft displacement. Also, a controller causes the driver to shut down when a predetermined amount of allowable wear of the main support bearings is reached.

Abstract: An inlet pipe (7) and a discharge pipe (9) of a centrifugal compressor (1) are provided with respective solenoid valves (16, 17) for allowing a flow of fluid in a direction of flow under operation of fluid compression. One end of a bypass pipe (20) is connected to a part of the inlet pipe (7) located between the solenoid valve (16) and an impeller room (6). The other end of the bypass pipe (20) is connected to a part of the discharge pipe (9) located between the impeller room (6) and the solenoid valve (17). The bypass pipe (20) is provided with a solenoid valve (21) which closes under operation of fluid compression of the centrifugal compressor (1) while opening under deactivating operation of the centrifugal compressor (1).

Abstract: A vibrating compressor of the present invention, which comprises a piston driving section for driving a piston by supplying a piston driving force, a displacement detecting section connected in an axial direction of the piston, an upper dead point position detecting section for detecting an upper dead point position based on a piston position signal from the displacement detecting section, and a driving force control section for changing the driving force supplied to the piston by the piston driving section according to a difference between the upper dead point position and a preset upper dead point position reference value immediately after the upper dead point position detecting section detects the upper dead point position, prevents its compression efficiency from decreasing due to stabilization and prevents a device from being damaged. In the vibrating compressor, it is also possible to calculate a stroke based on a detected piston position or to control the driving force based on a detected frequency.

Abstract: A photoresist storage and supply device. The device includes a control unit for generating a number of on/off signals. A number of gas supply valves are open to let gas pass according to the on/off signals. A number of photoresist solution storage vessels store photoresist solution and receive the gas from a corresponding gas supply valve. A buffer vessel receives the photoresist solution, under pressure of the gas, from a selected photoresist solution storage vessel. A liquid level sensor mounted on the buffer vessel detects the solution level in the buffer vessel and generates a control signal when the photoresist solution level in the buffer vessel is below a certain threshold. A gas exhaust valve is coupled to the control unit, and expels gas from inside the buffer vessel according to an on/off signal.

Abstract: A control system for an aircraft's electrically driven hydraulic pump. An electronic motor controller having closed loop feedback is utilized to directly control the prime mover speed in response to pump loading.

Abstract: A motion sensor for connecting to the housing of a gasoline dispenser which is used to dispense gasoline to vehicles. The motion sensor includes components to detect motion, such as that caused by a vehicle striking the dispenser housing, and provides a signal to a controller which cuts off electrical power through an electrical supply line to electrical components of the dispenser. With power disconnected from electrical components of the dispenser, potential arcing of electricity to those electrical components when they become damaged, or potential arcing when the electrical supply line becomes damaged can be prevented to potentially prevent a resulting fire or explosion.

Abstract: A positive displacement vacuum pump, in which a plurality of rotors are driven into synchronous operation by independent motors, uses a rotational position sensor making use of the electromagnetic induction effect for obtaining rotational position information for the individual shafts. The rotational position sensor is cooled.

Abstract: A downhole rotary pump driven by a polished rod and a string of sucker rods from the earth's surface by a variable or fixed frequency, three phase electric motor, is controlled by measurements of power consumed by the electric motor and by measurements of the rotary speed of the polished rod, the combinations of such measurements being indicative of the torque exerted on the polished rod. Determinations of such torque being either within or outside of predetermined upper and lower torque limits are used to either maintain the rotary speed of the downhole pump, or to vary the rotary speed of the downhole pump, or alternatively, to completely shutdown the downhole pump. Power generated by the motor is monitored and the measured value of power may also be used to terminate motor operation when a low power limit is exceeded.

Abstract: A method for operating a motor/compressor combination, especially for hermetically-encapsulated small refrigerating machines, comprises a compressor having a periodically operating displacement element, which is driven by a brushless motor (3). To start the motor, it is subjected to asynchronous and then synchronous commutation of its stator windings (7,8,9). For starting, the rotor is turned by asynchronous commutation from any given rest position to a starting position that facilitates running-up and is then started from that starting position. A motor/compressor combination for carrying out that method has a control arrangement (10) which, in asynchronous commutation, enables the current-application patterns to succeed one another in such a manner that the rotor is turned from the rest position to the starting position and is started therefrom. In that manner, the motor/compressor combination can be started reliably even in the event of unfavourable conditions.

Abstract: A contactless output section makes a circuit including a fan motor and an ac power source when a receive portion receives a command signal. A diode bridge and a direct current regulated circuit smooth and regulate dc current. An operation part is provided with power from the direct current regulated circuit, compares a measured temperature with a set temperature, and generates and provides a command signal for the receive portion of the contactless output section.

Abstract: A vacuum pump includes a plurality of rotors of different outer diameters accommodated in a housing so that a fluid transportation space is defined by the housing and the plural rotors. Rotary shafts are integrally formed with the respective rotors and a first motor, which is a high frequency motor, for driving the rotary shaft of the smaller diameter rotor as a driving shaft. A second motor, which is an AC servo motor or pulse motor, is provided for driving the other rotary shaft as a driven shaft. A rotation detecting device is provided adjacent each shaft for detecting rotating angles and/or rotating speeds of the first and second motors. Also provided is a fluid suction port and a fluid discharge port which are formed in the housing, and a control device for controlling rotation of the driven shaft based on data from the rotation detecting device so as to synchronize the rotation of the driven shaft driven by the second motor with that of the driving shaft driven by the first motor.

Abstract: A method and apparatus for controlling the speed of a progressing cavity liquid well pump by driving the pump with a variable speed drive device while measuring the amount of liquid production from the pump. The speed of the pump is varied in speed steps, either upwardly or downwardly, by the variable speed drive device while measuring liquid production, to maintain a linear relationship between liquid production and pump speed.

Abstract: Balancing the load between compressors is not trivial. An approach is disclosed to balance loads for compression systems which have the characteristic that the surge parameters, S, change in the same direction with rotational speed during the balancing process. Load balancing control involves equalizing the pressure ratio, rotational speed, or power (or functions of these) when the compressors are operating far from surge. Then, as surge is approached, all compressors are controlled, such that they arrive at their surge control lines simultaneously.

Abstract: A method and apparatus are disclosed for controlling a multicompressor station so that the overall work requirement of the station is minimized while maintaining the compressors in a non-surge conditions. The apparatus includes interconnected control loops for controlling the turbine speed of variable speed compressors or the throttling valves of constant speed compressors that determine a set of criterion for computing the value and sign of the first derivative of work performed by the station. The speed of each compressor is then set to reduce overall system work while maintaining discharge pressure of the station and maintaining the compressors in a non-surge operating format. The method includes the steps of computing the criterion, computing the value and sign of the first derivative of the work function and adjusting the compressor speed to minimize station work while maintaining the compressors in a non-surge condition.

Abstract: A ceiling fan having interchangeable plug-in circuit completion modules for varying the electrical driver circuitry of the fan. Each module is selectively designed to complete a motor driving circuit and/or a light driving circuit and are preferably installed in the switch housing of the fan. In addition, the modules contain selectively designed circuitry to enable a user to either manually or remotely control the fan. Since the modules are interchangeable, the driver control circuitry of the fan may be easily converted between manual and remote control.

Abstract: A device for constant, automatic regulation of water pressure and flow in a water supply plant, comprising an electric pump fitted in the main water pipe, an adjustable pressure switch connected to the main water pipe, and an electronic control unit, which switches the pump on if the pressure falls short of a predetermined level or switches it off if a predetermined pressure level is exceeded. The device is characterized in that a turbine, incorporated in the water pipe, acts as a sensor, cooperating with a rotation signal transmitter which is connected to the electronic control unit in order to keep the pump switched on as long as the sensor detects a flow of water.

Abstract: Air handling apparatus (10) delivers a volume of air at a generally constant flow rate regardless of changes in the operating conditions of a system with which the apparatus is used. A blower (12) pushes air from one point to another. The blower is operated by a blower motor (14). A switch (16) controls application of power to the motor. Sensors (20) are used to sense the current drawn by the motor and the motor's operating speed. A flow controller (22) establishes a desired air flow rate to be provided by the blower. A processor (18) is responsive to the sensed current (I), motor speed (S), an input (C) from the flow controller, and constants (K1-K4) related to performance characteristics of the blower to determine a torque required by the motor to produce a predetermined air flow rate. The torque value is determined as a function of the combined motor speed input from the sensor and an input from the flow controller.

Abstract: A vacuum pump system for multi-stage gas inlet systems and including a pumping unit formed of a turbomolecular pump and one or several further pumps arranged downstream of the turbomolecular pump and the rotors of which are located on the same shaft as the rotor of the turbomolecular pump, and an additional intermittently operated dry running pump, which discharges against atmospheric pressure.

Abstract: In a magnetically suspended type pump, an operating state of the pump can be obtained without using a pressure gauge and a flowmeter. In addition, in the case where the magnetically suspended type pump is applied to a blood pump, in order to reduce the number of connections in a flow path and to avoid thrombus formation, a correlation between current flowing in a motor and flow or a correlation between current flowing in the motor and pressure is obtained in advance, and the speed of rotation of motor is varied by a speed of rotation control circuit in response to an instruction from a CPU circuit, based on the obtained correlation between current and flow or between current and pressure, whereby flow or pressure is controlled.

Abstract: Precise control of the vertical motion of a piston or series of pistons within a cylindrical housing of a positive displacement pumping device to precisely set the discharge volume of viscous and non-viscous liquid products from the pistons. Uses a linear ball bearing screw actuated by an electronically-controlled servo motor. An electronic pulse generator incorporated in the servo motor provides pulses which are counted and used to set the maximum range of movement of the pistons.

Abstract: A pump having electronic and mechanical components which allow an individually adjustable operation. Certain components periodically transform a driving current for an electrical drive. An adjustable clock generator adjusts transformation frequency. Pumping volume is determined and limited as desired by means of a position detection device. The pump also includes components for measuring the driving current that interact with an adjustable current-limiting device, thus allowing the pumping pressure of the pump to be adjusted and limited. The pump may include several pump cylinders which are controlled by a position control circuit in such a way that the generated partial vacuum follows a predetermined time characteristic.

Abstract: The device comprises: a branch (5) from the outlet (M) of the pump to a cavity (7) partially delimited by a membrane (14); a moving element (16, 22, 24) in a casing (9); a spring (36) pushing said element (16, 22, 24) toward the membrane (14) and capable of yielding under the action of a relatively restricted pressure of the water which reaches said cavity (7) and acts on the membrane; and moving electrical contacts (26) on said element (16, 22, 24), interacting with fixed contacts (28) of a supply circuit of the pump, to enable the pump to be switched on and to switch it off in the absence of pressure acting on the membrane (14).

Abstract: A friction pump, which is equipped with at least one actively controlled magnetic radial bearing, wherein, in order to satisfy the extreme requirements necessary through the tight tolerances of pump elements and an emergency bearing, the high rotational speed and the magnetic support, a special control arrangement for the cooperation of rotor, positional sensors and the magnetic bearing control loop so that a safe operation of the pump at extreme requirements is assured in a simple manner without the use of any additional constructional elements.

Abstract: A pump system comprising a pump having a centrifugal impeller driven by an electric motor, a pair of upper and lower float switches for detecting a high water level HWL and a low water level LWL, respectively, a controller for outputting a control signal on the basis of preset rotational speeds for low and high-speed operations and a preset rotational speed increment rate, together with output signals from the upper and lower float switches, and a frequency converter for varying the rotational speed of the electric motor on the basis of the control signal from the controller, the pump system is capable of exhibiting the required pumping performance and of controlling the flow rate and the pump head.

Abstract: A booster compressor system modulates discharge pressure with a proportional regulator in fluid communication between the compressor discharge and a servo control for a valve to the compressor inlet. The servo control comprises a double acting piston connected to a valve control rod. In one embodiment, the proportional regulator is of a negative signal type and communicates to a side of the piston for urging the piston to a valve opening position. A valve closing pressure is applied by a non-relieving regulator in fluid communication between the compressor discharge and the other side of the servo control piston. As the discharge pressure increases, the proportional regulator out let pressure decreases thereby resulting in the servo control allowing the intake valve to the compressor inlet to close. This, in turn, reduces the compressor discharge pressure thereby resulting in the proportional regulator controlling the valve to partially open once more.

Abstract: A solenoid valve for a water purification system. The solenoid valve contains a fluid valve which can move between an opened position and a closed position, and a coil which moves the valve to the open position when a first voltage is supplied to the coil and maintains the valve in the open position as a second voltage is supplied to the coil. The coil is coupled to a control circuit which initially supplies the first voltage to the coil when the valve is to be opened, and then reduces the first voltage to the second voltage after the valve is in the open position.

Abstract: A pump control system has a pump unit composed of a turbo pump, a motor for operating the turbo pump, and a frequency/voltage converter for generating a frequency and a voltage to energize the motor. The rotational speed of the turbo pump is varied in order to equalize the current of the motor to a constant current irrespective of the head of the pump. The pump can be operated to take fully advantage of the current capacity of the motor.

Abstract: A soft-start pump controller system for controlling a pump motor includes a switching device for supplying power to the pump motor; a periodic duty cycle generator for periodically actuating the switching device at a fraction of the full duty cycle to operate the pump at a reduced, quieter level; a sensor for sensing the current drawn by the pump motor; a reference circuit; and a liquid detector for detecting the presence of the liquid to be pumped, responsive to the sensor and the reference circuit, for overriding the periodic duty cycle generator and actuating the switching device to operate the pump motor continuously at full power when the motor current exceeds a predetermined level indicating liquid is present.

Abstract: An improved dual-stage pump system is provided for the accurate pumping and filtering of viscous fluids. Two hydraulically activated pumps are provided in series with a filter and reservoir disposed in-line between the two pumps. The reservoir acts as a source bottle for the second pump and allows the first pump to pump the viscous fluid through the filter at a rate independent of the dispensing rate of the second pump. By operating the first pump at a rate independent of the second pump, back pressure at the filter is avoided. Each hydraulically activated diaphragm pump is equipped with an improved diaphragm that is pre-formed to the geometries of the process fluid cavity thereby eliminating any inaccuracies in the operation of the pumps due to expansion of retraction of the diaphragm during pump operation.

Abstract: An axial-flow pump combined with an electric motor coaxially arranged therearound. The rotor (1) and stator (2) are common to both the electric motor and the pump. The rotor comprises a central tubular portion (11) defining a central channel (14) with a wall (15) provided with blades (16). The blades preferable do not extend as far as the channel axis (3) so that they define a central free area therealong. The outer portion of the rotor (1) has pairs of permanent magnets (24, 25) with stator coils (9) therebetween. The coils are actuated and deactuated by an electronic switching device (28) controlled by sensors (36, 37) for sensing markings on the rotor. The length of the rotor is smaller than its outer diameter. Said pump may be used to pump liquids or gases and drive vehicles, particularly submarines.

Abstract: A medical infusion pump (10) including an improved electric motor assembly (256). The medical infusion pump (10) includes a pumping mechanism (250) and a pump chamber (132) in an operative position with respect to the pumping mechanism (250), the pumping mechanism (250) manipulating the pump chamber (132) to pump liquid through the pump chamber. An electric motor (256) having a rotatable drive shaft (316) is operably linked to the pump driving mechanism (250) and the pump driving mechanism (250) pumps a select amount of liquid through the pump chamber (132) on each rotation of the electric motor drive shaft (316). The improved electric motor assembly (256) includes a motor having a portion of a drive shaft (388) extending therefrom. A magnet (392) is attached to the extending portion of the drive shaft for rotation with the drive shaft.

Abstract: A hand-held vacuum pump with an attached vacuum limiter valve is disclosed. The pump includes a cylinder coupled with a handle, a piston in the cylinder coupled with another handle, along with a suitable valving assembly for allowing a vacuum to be drawn at an inlet of the pump. More particularly, there is also disclosed a vacuum limiter which can be attached to or form an integral part of the pump. The vacuum limiter includes a valve which is attached to the cylinder outlet port and which is adjustable for allowing the limit vacuum to be set.

Abstract: An oil pump driving device drives an oil pump combined with a transmission coupled to an engine for supplying working oil to lubricate the transmission and enable the transmission to make gear shifts. The transmission includes a first power transmitting mechanism for connecting the output shaft of an electric motor to the drive shaft of the oil pump, and a second power transmitting path for connecting the output shaft of the engine to the drive shaft of the oil pump. A controller for selecting one of the first and second power transmitting mechanisms at a time selects the first power transmitting mechanism to drive the oil pump with the electric motor when the rotational speed of the output shaft of the engine is lower than a predetermined speed, and selects the second power transmitting mechanism to drive the oil pump with the engine when the rotational speed of the output shaft of the engine exceeds the predetermined speed.

Abstract: Fluid pounding in a pumpjack is minimized by dictating the length of the run cycles of the pumpjack. The pumpjack is first allowed to pump down until a fluid pounding state is reached, at which time it is shut down. The time it takes to reach this state is monitored. Using the length of time it took to reach the fluid pounding state, the pumpjack is set to run a predetermined number of dictated cycles for a length of time which is 70-99% of the time it took to reach the fluid pounding state. During these predetermined number of cycles if the pumpjack again reaches a fluid pounding state the time is reset based on this new information, and the number of predetermined number of dictated cycles left is finished. After the predetermined number of cycles has finished, the process is repeated by allowing the pumpjack to run to a fluid pounding state.

Abstract: Air handling apparatus (10) for delivering a volume of air at a generally constant flow rate regardless of changes in the operating conditions of a system with which the apparatus is used. A blower (12) pushes air from one point to another. The blower is operated by a blower motor (14). A switch (16) controls application of power to the motor. Sensors (20) are used to sense the voltage supplied to the motor, the current drawn by the motor, and the motor's operating speed. A flow controller (22) establishes a desired air flow rate to be provided by the blower. A processor (18) is responsive to the sensed voltage (V), current (I), and speed (S), an input (C) from the flow controller, and constants (K1-K4) related to performance characteristics of the blower to determine a torque required by the motor to produce a predetermined air flow rate. The torque value is determined as a function of the combined motor speed input from the sensor and an input from the flow controller.

Abstract: An electric contactor for the motor of a reciprocating pump such as an oil well walking beam pump, and other cyclic loads, uses the power drawn by the load to determine the phase angle of the pump without the need for a separate phase signalling sensor. The contactor couples the electric pump motor to a power line, and has a power sensor and peak detector. The power sensor can be responsive to RMS AC power or simply to current amplitude and polarity. The motor passes through a minimum power at the extreme top and bottom of a pump stroke, and the phase position at the top of the stroke is preferably detected by sensing for the power reversal that occurs as the momentum of the pump causes regeneration by the motor. The contactor can have overcurrent and/or undervoltage protection features, can include contacts for rearranging the motor windings to vary pump operation, and can report the phase to a pump control and monitoring system, whereby process variables are assessed as a function of phase.

Abstract: A solution pumping system is disclosed which is embodied as a disposable pump cassette including a self-contained positive displacement pump, and an associated pump driver including a reciprocable pump piston for driving the pump of the cassette. This system is particularly suited for use in compounding in preparation of parenteral solutions for administration to patients. In order to promote high liquid output with minimum peak pumping pressures, the controls of the system operate to provide a "square" pumping pressure waveform, thus optimizing performance of the system. This is achieved by selectively varying the velocity of the pump piston during its operation.

Abstract: An apparatus and method for mixing and delivering plural liquid components in a selected volume ratio. For each component, a separate motor drives a separate rotary gear pump that delivers the component to a common mixing and delivery device (spray gun). The speed of each motor, and correspondingly the volume of fluid delivered by that pump, is determined by a respective programmable computer. The individual computers are interlinked, with one master computer and the rest slave(s). Desired motor speeds are input into the computers in a selected ratio. A change in the speed of the master motor therefore produces a corresponding change in the speed of a slave motor according to the ratio. Actual motor speed is monitored and transmitted to the respective computer for feedback control. A simple manual ratio test is provided for calibration of the system. Each pump is magnetically coupled to its respective motor drive shaft.

Abstract: In a suction-controlled ring gear pump a continuous elimination of the vacuum occurring in the displacement cells of the pump at higher speed is achieved by a long distance of the displacement cells from the end of the suction region to the start of the outlet opening and the resulting diminishing of the displacement cells. To avoid squeeze oil when operating at low speed, the displacement cells following each other in the displacement direction between the gear teeth are each connected to the adjacent displacement cells by overflow passages which pass through the gear teeth and in which check valves prevent a flow against the displacement direction. To obtain an increased pump power when reaching specific operating parameters the flow resistance in the suction conduit can be reduced and the effective edge of the pressure kidney shifted forwardly by connection of a further preceding pressure kidney.

Abstract: An improved augmentor fuel supply system including a fuel source, a pump for pressurizing the fuel, a flow control means for controlling the flow and pressure of fuel to a fuel disbursement means (e.g., an augmentor) and a return path for recirculating unburned fuel. The flow control means includes a restrictor means such as a small orifice in parallel with a controllable valve. The restrictor means allows fuel to flow to the fuel disbursement means when the controllable valve is shut off. Further, according to the present invention, a second restrictor means, such as a small orifice is included in the return path. Finally, a check valve is included in the return path to ensure that fuel does not flow into the augmentor through the return path.

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: There is disclosed herein a small and compact vacuum pump which serves as a portable vacuum source. The pump basically includes a cylinder coupled with a handle, and a piston in the cylinder coupled with another handle, along with a suitable valving assembly for allowing a vacuum to be drawn at an inlet of the pump. More particularly, there is also disclosed a vacuum limiter which can be attached to or form an integral part of the pump. The vacuum limiter includes an assembly having a pair of valves one of which is adjustable for allowing the limit vacuum to be set. The adjustable valve is a metering check valve and the second valve is a holding check valve upstream of the first.

Abstract: A rotary screw compressor with a lift valve comprising a valve member having two rigidly connected cylindrical sections of different diameter. The valve member is displaceably mounted in a valve housing extending through the high pressure end wall of the compressor. The valve housing sealingly surrounds each of the cylindrical sections. The section of the smaller diameter and the corresponding part of the valve housing face the working space of the machine. The lift valve is mounted such that the direction of motion of the valve member is inclined relative to the axial direction of the compressor.

Abstract: One or more throttles are accommodated in a compression line and/or in a suction line to damp surges in reciprocating compressors. The size of the open cross-section of the throttle can be varied. The size is established to prevent surges from exceeding a prescribed limit.

Abstract: A multicylinder rotary compressor has a plurality of cylinders housing rolling pistons which are rotated inside the cylinders by a common crankshaft. Each cylinder has a separate suction pipe. At least one of the suction pipes has a check valve which may be closed to unload the cylinder to which the suction pipe is connected. The check valve has a housing and a slider which can slide inside the housing between an open position and a closed position. The check valve may be closed by introduction of high-pressure refrigerant gas into the space beneath the slider to push it to the closed position when a cylinder is to be unloaded. In another form of the invention, the check valve is closed by a spring made of a shape-memory alloy and a heater for heating the spring above a prescribed temperature at which the allow changes shape. When a cylinder is to be unloaded, the heater is turned on, and the shape-memory alloy deforms into a shape such as to force the slide to the closed position.

Abstract: In an electromagnetic pump, the inner end of an outlet pipe fixed in a pump housing extends for a predetermined length inside a sleeve housing a plunger to form a pump delivery pulsation absorption chamber around the outlet pipe. The inner end opening of this pipe is selectively closed by a control valve serving as a guide member for slidably guiding a valve body of a delivery valve along the axial direction. The fuel leakage prevention control valve and the pulsation absorption chamber are simply and optimally formed with a single construction.

Abstract: Vacuum pumping system comprises a plurality of vacuum processing vessels, semiconductor processing reactors, and the like, connected to a common manifold evacuated by a generously large central vacuum unit. The manifold is maintained at a substantially constant designated pre-set pressure higher than the pressures within the reactors by means of a gas bleed inlet valve controllably feeding an inert gas into the manifold. A blower package with valving, interposed between each reactor and the common manifold, discharges directly into the manifold and prevents pressure surges and excursions in the manifold and reactors as well as permitting each reactor to operate at different pressures independently of the existing manifold pressure.

Abstract: A scroll type compressor is disclosed which includes a housing with an inner chamber and fluid inlet and outlet ports connected to the inner chamber. A fixed scroll, which is mounted within the housing, has a circular end plate from which a first spiral wrap extends. An orbiting scroll also is mounted within the housing for orbital motion with respect to the fixed scroll. The orbiting scroll has a circular end plate from which a second spiral wrap extends; the first and second wraps interfit to define at least one pair of sealed off fluid pockets. The end plate of the fixed scroll partitions the inner chamber of the housing into a suction chamber and rear chamber. The rear chamber is divided into a discharge chamber and an intermediate pressure chamber. The circular end plate of the fixed scroll has at least one pair of holes symmetrically positioned to connect the sealed off fluid pockets to the intermediate pressure chamber.

Abstract: A diesel engine fuel supply system having an injector pump, a fuel tank, a fuel inlet conduit between the fuel tank and the injector pump and a fuel return conduit between the injector pump and the fuel tank, a venting fuel valve including a valve body, an adapter for mounting the valve body on the injector pump, a fuel inlet on the valve body for receiving the fuel inlet conduit, a fuel outlet on the valve body for transmitting fuel to the injector pump, a vent in the valve body in communication with the atmosphere, a valve spool in the valve body movable to a first position for effecting communication between the fuel inlet and the fuel outlet to supply fuel to the injector pump while preventing venting of the fuel outlet to the atmosphere through the venting means, and the valve spool being movable to a second position for preventing communication between the fuel inlet and the fuel outlet and for effecting communication between the injector pump and the atmosphere to thereby vent the injector pump and pre