Abstract: An infusion pump incorporates a cassette formed by bonding of two substantially flat sheets. The fluid to be infused to the patient comes into contact only with the cassette. The cassette includes first and second flexible sheets which define a pumping chamber therebetween. The infusion pump is provided with a pumping member having a hub and a plurality of petal-shaped sections extending radially outward therefrom and pivotal relative thereto. A stepping motor can be operated to move the pumping member against the second flexible sheet to decrease the volume of the pumping chamber and pump fluid to the patient. A load cell monitors the force exerted by the stepping motor on the hub. An outlet restriction valve is electronically controlled by a second stepping motor in response to the pressure sensed by the load cell to control pumping to a predetermined pressure.

Abstract: A device for generating a vacuum comprises a liquid-ring vacuum pump driven by an electric motor and operating with a working fluid. A mixture of compressed air and working fluid from the pump flows to a preseparator which separates a major portion of the working fluid from the gaseous mixture. The separated working fluid is fed from a reservoir in the preseparator via a liquid cooling coil back to the liquid-ring vacuum pump, while the gas still loaded with a residue of the working fluid is fed to a fine separator by means of a gas cooler, working fluid separated in the fine separator being returned to the pump via a return line. The preseparator and the fine separator are physically spaced from one another. The gas cooler and the liquid cooling coil are also physically spaced from one another and are located in the path of the cooling air stream for the electric motor.

Abstract: A closed loop control is provided to control pressure and/or temperature in a system where one or more liquid ring vacuum pumps evacuate a recipient. The suction ability of the liquid ring vacuum pumps is controlled either by speed control, operating water temperature, switching-on and -off of pumps or bypass-air. Simultaneous control of all operating characteristics is achieved with a programmable electronic controller.

Abstract: An electronic control system for a variable displacement pump comprises apparatus for sensing the actual position of the displacement determinative element and the actual rotational speed of the pump cylinder block, and for producing representative signals which are combined to produce a signal indicative of actual output flow rate. The displacement determinative elements position and the cylinder rotational speed are sensed directly by sensors mounted within the housing of the pump. The speed sensor is disposed in close proximity to, and aligned with marks inscribed on, the outer surface of the rotatable cylinder block. The volumetric efficiency of the pump is also sensed by and used to determine the actual flow rate.

Abstract: A bellows pump with the improvement of an adjustable index for uniformly controlling the amount of fluid displaced in each expansion and compression cycle.

Abstract: Herein disclosed is an ejector pump which can be used favorably with a sucking disk for carrying an article. In the bore of a pump body, there are fitted a nozzle block having a nozzle hole and an ejector block which has an ejector hole aligned with the nozzle hole of the nozzle block, so that a suction chamber formed between the nozzle hole and the ejector hole may communicate with a suction port which is formed in one side of the pump body. Fitted in the pump body, too, is a spool valve for opening or closing a communication passage providing communication between the nozzle hole and the compressed air inlet port of the pump body. The spool valve is controlled by an electromagnetic change-over valve disposed outside of the pump body. The pump has the advantage that the compressed air can be supplied at a high flow rate to establish a strong sucking force even with a relatively small-sized electromagnetic change-over valve.

Abstract: A variable capacity radial piston pump is disclosed, in which the radially outer ends of the pistons are constrained by engagement with the radially inner surface of a cam ring assembly that includes a radially inner ring, a radially outer ring, and rollable bearings between the inner and outer rings. The cam ring is shiftably mounted in the pump housing so that its magnitude of eccentricity relative to the pump rotor can be varied in order to vary the magnitude of suction and compression forces generated in the working fluid in the rotor chambers associated with the respective pistons. Several mechanisms for affecting the cam ring/rotor eccentricity variation are shown and described.

Abstract: A double acting type compressor has a main body which is formed by a cylinder block and a pair of cylinder heads secured to opposite ends of the cylinder block. The main body is formed therein with a pair of discharge chambers arranged at opposite ends thereof, a discharge passageway communicating the discharge chambers with each other, and a discharge port communicating substantially directly with the discharge passageway. A pulsation attenuating means formed of restriction hole means is provided between each of the discharge chambers and the discharge passageway. Compression medium in each of the discharge chambers flows into the discharge passageway through the restriction hole means of the pulsation attenuating means, while simultaneously having its pulsations attenuated, and then is supplied into an associated external circuit through the discharge port.

Abstract: A liquid fuel pumping apparatus for supplying fuel to an internal combustion engine has a rotary distributor member in which is mounted a plurality of pumping plungers which are engaged at their outer ends by cam followers which engage the internal surface of a cam ring. The distributor member is axially movable to vary the quantity of fuel supplied. Each follower includes a roller and a shoe and in order to reduce the amount of material required to produce the cam ring, the rollers are of a length substantially equal to the width of the cam ring and are held against axial movement relative to the cam ring. The shoes are held against axial movement relative to the distributor member. The width of the cam ring and the roller are such that the safe Hertzian stress in the cam ring is not exceeded, the additional width of the cam ring to accommodate the movement of the distributor member in previous designs not being required.

Abstract: An evacuation system for removing corrosive gas from a process tube during processing of semiconductor wafers. An aspirator is used for an initial pump down of the process tube to approximately 200 TORR. The aspirator has no moving parts and does not react to the corrosive gas. The aspirator is controlled by a control circuit which utilizes a series of relays to open a ball valve and start the aspirator. After 200 TORR is reached, the aspirator is shut off, the ball valve is closed and a high vacuum pump is utilized to complete the evacuation. Because the vacuum pump is exposed to a reduced volume of corrosive gas, its lifetime is correspondingly increased.

Abstract: A control circuit for a radial piston pump that uses a four position control valve and an orifice to regulate fluid flow from the stroke control chamber to the pump inlet. The control valve also regulates the addition of high pressure fluid for destroking the pump and provides pressure relief of the pump output during destroking to eliminate pressure spikes. Elimination of pressure spikes is done by an overshoot function which relieves high pressure output fluid directly to the pump inlet and to the pump control chamber while also venting the pump control chamber to the pump inlet. V-notch openings in the control valve for regulating the addition of high pressure fluid to the stroke control chamber enhance control during steady state operations. The circuit also uses a down sized orifice between the stroke control chamber and the pump inlet which allows a portion of the pump destroking phase to be done by piston leakage flow, thereby minimizing control fluid usage.

Abstract: A fluid machine comprises a cylinder block mounted on a rotary shaft, a rotary plate an axis of which is intersecting with an axis of the rotary shaft by an acute angle, a gear engaging mechanism for engaging the rotary plate with the rotary shaft to cyclically rotate the same, a piston supported by the rotary plate and inserted into a throughhole provided in the cylinder block a suction system and a delivery system for effecting suction and delivery operation by a rotation of the cylinder block and the piston, a spherical contact portion disposed between the rotary plate and the rotary shaft and adapted to receive thrust generated between the same, and a passage for leading to the spherical contact portion a high-pressure working gas including lubricating oil generated in the delivery system.

Abstract: A gas bearing system for a piston 24 of a linear compressor 20 in which gas from the piston head space 26 is injected into a high pressure reservoir 106 within the piston when the working fluid in the piston head space is at high pressure. In one embodiment, gas from a low pressure reservoir 104 is exhausted into it when the piston working space fluid is at low pressure. Gas flow is directed between high pressure and areas of low pressure during operation of the piston. This gas flow is directed between the piston and its surrounding sleeve 30 in a manner which holds the piston 24 in suspension away from the sleeve 30 to thereby reduce the friction and wear experienced by the piston and sleeve.

Abstract: A fluid displacement rotary machine is disclosed, more specifically a rotating piston compressor enclosed in a casing formed with a vent through which may freely enter the gas or vapor to be compressed. Radial cylinders are part of a rotor rotatably supported by a shaft co-axial with the rotor. The rotor is power-driven. The piston connecting rods rotate about a stud fixed to the casing and eccentric to the rotor. Each cylinder head includes a scoop rotating therewith and adapted to channel the gas or vapor into the cylinder head; and further includes a delivery pipe connected to a bore formed in the rotor supporting shaft which extends externally of one casing end wall. The cylinders and the pistons rotate in respective annular paths and yet the pistons make a reciprocating movement within their cylinders because of the eccentric mounting of the stud relative to the rotor axis.

Abstract: A portable engine-pump assembly for use in firefighting applications is constructed of a high-speed, lightweight engine and a double-suction pump. The engine is arranged with a vertical crankshaft for driving the pump which is mounted adjacent thereto with a vertical pump shaft coupled to the crankshaft. The assembly is designed to provide high lift, high efficiency and a steady high flow volume and to be compact and light in weight.

Abstract: A hydraulic radial piston machine for stepplessly displaceable piston stroke has a plurality of pistons which are formed as roller bodies and abut linearly with their circular spherical regions against a control curve which is formed on a control ring displaceable relative to a cylinder body of the machine, wherein the control curve is formed as a symmetrical spatial curve such that the curve regions which form both the inner dead point for the pistons and the outer dead point for the pistons change in the displacement direction of the control ring.

Abstract: A liquid pump motor control for a liquid chromatograph. The control detects when the pump needs to be refilled. Then, the pump motor is accelerated at a first rate for a given number of pulses. Then the motor is accelerated at substantially its maximum rate until a selected maximum speed is reached. Thereafter the speed is maintained at its maximum until the time calculated to begin deceleration. The motor is then decelerated substantially at its maximum deceleration rate until the speed is close to the final desired speed. Then deceleration occurs at a slower rate for a fixed number of pulses. The number of pulses applied to the stepping motor from the beginning of acceleration until the end of deceleration is constant regardless of the beginning or ending pulse rates.

Abstract: A fluid-raising apparatus includes a compression chamber which receives liquid, from an elevated source, such that gas in the chamber is pressurized and used to lift fluid through a vertical conduit. When the chamber fills with liquid, a float lifts a drain plug so that draining commences automatically. The effluent passes through a discharge tube wherein, during draining, the liquid pushes on a piston. The piston, in turn, holds a liquid inlet valve closed until draining is complete.

Abstract: A suction valve for a small refrigeration compressor is in the form of a thin sheet metal reed having a sealing portion adapted to make sealing contact with a valve seat around the suction port on a valve plate. The valve reed is formed from a valve sheet by an outline defining cut so that the valve reed is integral with the sheet. The valve reed has a reduced width neck portion and in this neck portion the material is plastically deformed along a bend line so that in a normal unstressed condition the sealing portion of the reed is spaced away from the valve seat by a slight distance and as soon as the piston starts on the compression stroke the fluid pressure forces the sealing portion into sealing engagement to prevent back-flow through the suction port. When the piston starts the suction stroke, the biasing of the valve reed causes the sealing portion to move out of engagement with the valve seat before there is a substantial pressure differential across the suction valve.

Abstract: A fluid device of the axial piston type having high and low pressure operating passages, one of which may be an inlet and the other an outlet depending upon the pumping or motoring function of the device. The fluid device which may be of the fixed or variable displacement type has a rotatable cylinder barrel with each end of a plurality of pistons disposed for reciprocation within cylinder bores in the cylinder barrel, and cylinder ports successively communicating each of the cylinder bores with arcuate inlet and outlet passages formed in a valving face disposed at one end of the cylinder barrel. The other ends of the pistons are drivingly engaged by an inclined thrust plate assembly disposed to impart a reciprocal stroking movement to the pistons within the cylinder bores as the cylinder barrel is rotated.