Abstract: Controls for a dual element pump having first and second pumps with separate outputs wherein a modulating valve is positionable to control the amount of fuel delivered by a first pump to a fuel control and additionally to selectively control the utilization of flow delivered by the second pump. The flow from the second pump is bypassed when not needed through a pressure regulating valve having a minimal setting and with the setting of the pressure regulating valve being increased by operation of the modulating valve prior to the flow from the second pump being added to the flow from the first pump. The control of the modulating valve is by means of a flow control valve operating through dynamic compensator structure. The flow control valve is positioned by a head sensor including a jet pipe shiftable from a null position by a pressure differential signal delivered by two pressure sensing lines sensing a pressure differential across a variable area opening in a valve forming part of the fuel control.

Abstract: The invention relates to a venting device for oil-burning installations. A float arranged in a venting chamber controls both a connection between the venting chamber and the surrounding atmosphere and a connection between the venting chamber and the suction side of an oil pump included in the installation.

Abstract: A swash plate compressor is disclosed which is provided with a compression capacity control apparatus capable of returning an output pressure of a high pressure chamber of one cover to a low pressure chamber of the same cover. The control apparatus comprises a delivery chamber which is communicated with a high pressure chamber of the other cover, isolated from the high pressure chamber of the one cover and connected to a delivery conduit. The control apparatus also comprises a compression capacity control passageway providing communication between the delivery chamber and the low pressure and high pressure chambers of the one cover. A rotary three-way valve member is disposed in the control passageway to interrupt the communication between the delivery chamber and the high pressure chamber of the one cover while establishing communication between the low pressure and high pressure chambers of the one cover.

Abstract: A lubricant applying system which may have a plurality of lubricant injectors along a lubricant supply/return passage which receives lubricant under predetermined pressure through one end from a source for discharging and sequentially recharging the injector in one phase and in a second phase after the recharging permitting return of surplus lubricant from the injector through the passage to the lubricant source. A pressure sensor connected to the opposite end of the passage monitors pressure conditions in the passage. The lubricant injector has a displacement plunger and a cooperatively related metering plunger. The displacement plunger is responsive to lubricant passage line pressure which drives the displacement plunger in a displacement stroke, during which a passageway is connected by the displacement plunger with a metering chamber from which the metering plunger is driven by the pressure and the metering chamber charged while the metering plunger closes the lubricant passage.

Abstract: In an oil pump having two pump cartridges each acting as independent pumps, a pair of suction passages and a pair of discharge passages opened in a pair of pump chambers in the pump cartridges are formed in one pump body secured to one side of the cartridges, a flow control valve is contained in an opening extending in an axial direction of the pump body, and a pressure sensitive flow passage change over valve is contained in another valve opening perpendicular to the valve opening. The two valve openings are communicated with the discharge and suction openings.

Abstract: In an oil pump of the type comprising a cartridge having an elliptical cam ring in which a rotor having a plurality of vanes is rotated to form a pair of pump chambers symmetric with respect to an axis of rotor, and a pair of suction passages and two pairs of discharge passages are provided for the pair of pump chambers. A valve opening is formed coaxially with the rotor in a pump body secured to one side of the cartridge to contain the spool valve. A metering orifice is provided in a discharge passage to actuate the spool valve in response to a pressure differential such that when the pump speed is low all outputs of both pump chambers are supplied to a load, whereas when the pump speed is high a portion of the outputs is supplied the suction side. According to this construction it is possible to decrease power consumption and to decrease the size and weight of the oil pump.

Abstract: This liquid flow control apparatus is a delayed closure valve mechanism intended for use in an unloading bypass between the outlet and the inlet of a pump for supplying fuel to an oil burner. The valve mechanism includes a conduit having a large diameter section between two small diameter sections. A ball valve having a diameter smaller than the large diameter section and larger than the two small diameter sections is captured within the large diameter section. The large diameter section extends upwardly, so that the ball is biased by gravity to its inlet end. When the pump starts, the ball is moved by the discharge pressure of the pump until it engages the upper end of the large diameter section, whereupon the unloading bypass is closed and the discharge pressure of the pump is effective to open a cut-off valve leading to the nozzle of the oil burner. The length of the large diameter section determines the time delay between the starting of the pump and the delivery of oil to the nozzle of the burner.

Abstract: A compressor comprises a main compressor body of compressing air, an unloader valve device provided at the suction side of the main compressor body, a bleeding pipe provided between the ejection side of the main compressor body and the unloader valve device, and a controlling valve mechanism provided inside the bleeding pipe. The controlling valve mechanism opens by detecting the fluid pressure at the ejection side of the main compressor body. Further, the unloader valve device has a check valve which opens upon-no-load operation and stopping of the operation of the main compressor body, a main valve which opens due to the air released through the bleeding pipe when the controlling valve mechanism opens, a bleeding passage for releasing the released air supplied to the suction side of the check valve, and a relief passage which communicates when the main valve opens, to release the released air to the suction side of the main compressor body.

Abstract: A pair of pump bodies are disposed on the opposite sides of a rotor having vanes and a cam ring disposed in surrounding relationship with the rotor. These pump bodies serve the function of a sideplate and a pressure plate. The rotary shaft of the rotor is rotatably journaled in one of the pump bodies. A flow control valve is disposed in alignment with the axis of the other pump body, and a relief valve is disposed in surrounding relationship with the flow control valve. In this manner, the construction of various parts is simplified and the number of parts is reduced while simultaneously facilitating the machining operation. The overall length and the outer diameter as well as the weight of the pump can be reduced, advantageously reducing the manufacturing cost of the pump.

Abstract: A process to control the delivery of a single screw compressor comprising a screw meshing with two pinion wheels and rotatable inside a casing. A channel with obturating means is provided to connect the high pressure orifice pertaining to a one pinion-wheel and the low pressure orifice. Auxiliary orifices are arranged to connect the various zones of the casing exposed to pressure with the low pressure orifice, said auxiliary orifices being provided with obturating devices. Said orifices are sequentially opened to diminish the delivery, starting from the orifice located near the low pressure orifice. First, the orifices pertaining to the first pinion wheel are sequentially opened. Then, the channel connecting the high pressure orifice of the first pinion and the low pressure orifice is opened. Then, the auxiliary orifices pertaining to the second pinion are sequentially opened.

Abstract: A hydraulic fluid power system incorporating a supplemental pressurization system at the intake side of a hydraulic pump. The supplemental pressurization system includes a supplementary reservoir in communication with a primary fluid accumulator and an intake conduit of the hydraulic pump. The reservoir supplements hydraulic fluid flow to the intake side of the pump whenever intake line pressure drops below one atmosphere. Should the combined hydraulic fluid flow from the accumulator and the reservoir be insufficient to raise the intake pressure to prevent cavitation of the pump, an air ingestion valve opens to supply air to the intake side of the pump until proper pressurization is achieved, whereby the supplemental pressurization system closes off.

Abstract: A positive displacement pump system has two delivery passages communicating under the control of a valve with a main discharge passage and/or an overspill duct. The valve is constituted by a valve member slidably mounted in a valve bore and the valve member has lands and intermediate recesses controlling communication between the delivery passages and the overspill duct. The pressures upstream and downstream of a discharge orifice in the discharge passage are applied to the valve member in opposition to each other, increase of the pressure drop tending to move the valve member to increase the amount of fluid passed to the overspill duct. To overcome the known tendency for a valve member to be subjected by the hydraulic forces to a large closing force when the valve is open to only a small extent, the valve is designed to provide for a relatively large opening force at least when the valve is commencing to open.

Abstract: The present hydraulic system for driving a submersible pumping unit has an above-ground pump for pumping oil through a hydraulic motor in the submersible pumping unit which has a gate valve to prevent the reverse flow of water after the submersible pumping unit is turned off. A pressure regulating valve limits the oil pressure to the hydraulic motor. The inlet flow to the above-ground pump is filtered. In the present improvement, the hydraulic surge at start-up and shut-down is cushioned by bypassing hydraulic fluid through an accumulator which causes pressure at the motor in the submersible pumping unit to build-up relatively gradually at start-up and decrease relatively gradually at shut-down.

Abstract: A positive displacement pump system has first and second delivery passages for the pumped fluid and a main discharge passage. A control valve operating in dependence on the pressure drop across an orifice in the discharge passage diverts through overspill porting a proportion of the flow through the second delivery passage, the remainder added to the flow from the first delivery passage and passed to the discharge passage. The control valve also regulates the by-passing of a proportion of the flow from the first delivery passage to the overspill porting. As the said pressure drop increases, the control valve first increases the proportion of the flow from the second delivery passage diverted to the overspill porting and, as the pressure drop increases further, then commences to by-pass fluid from the first delivery passage to the overspill port, the quantity by-passed increasing with increase of said pressure drop.

Abstract: A fuel injection pump in which a relief channel is formed which communicates with the pump working chamber and is arranged to be blocked by a valve means, associated with a valve actuating means responsive to a pressure varying with engine r.p.m., during starting of the engine so that the fuel injection quantity is increased. Thus, improved starting characteristics of the engine can be obtained. Said relief channel may comprise a first channel communicating with the pump working chamber, and a second relief channel which has a portion thereof extending in the pump plunger to terminate in an outer periphery of the bottom end of said plunger and is so disposed as to communicate with the pump suction chamber after a predetermined delivery stroke length or prestroke has been executed. Communication between said first and second relief channels is adapted to be interrupted by said valve means at less than a predetermined engine r.p.m.

Abstract: A positive displacement pump system provides first and second delivery 11, 12 passages of which the first passage 11 communicates with a main discharge passage 15 containing a discharge orifice 17. The second delivery passage 12 opens to a valve bore and is in permanently open communication with the first delivery passage through an axial passage 29 in a valve member 20 slidably mounted in the valve bore. Lifting of the valve member with increasing pressure drop across the orifice 17 places the first delivery passage in communication with an overspill port 14. The pressure at the upstream and downstream sides of the orifice are applied against the lower end and the upper end 28 of the valve member so that the valve operates to maintain the pressure difference constant. The pressure difference between passage 29 and that applied against the upper end 28 of the valve member is therefore also substantially constant, so that leakage from passage 29 past the upper end 28 is constant.

Abstract: A fuel injection pump in which a relief channel is formed which communicates with the pump working chamber and is arranged to be blocked by a valve means, associated with a valve actuating means responsive to a pressure varying with engine r.p.m., during starting of the engine so that the fuel injection quantity is increased. Thus, improved starting characteristics of the engine can be obtained. Said relief channel may comprise a first channel communicating with the pump working chamber, and a second relief channel which has a portion thereof extending in the pump plunger to terminate in an outer periphery of the bottom end of said plunger and is so disposed as to communicate with the pump suction chamber after a predetermined delivery stroke length or prestroke has been executed. Communication between said first and second relief channels is adapted to be interrupted by said valve means at less than a predetermined engine r.p.m.

Abstract: Rotary displacement pump, of which the delivery pressure can be adjusted by modifying the losses in the gap between the lateral flank or flanks of one or more of the gear wheels and the house in which these gear wheels are enclosed, at the place of this gap also the mouth of a channel being present, which channel is or can be connected to a return line.

Abstract: A fluid pumping system comprises a fluid pump having multiple fluid outlet flows coupled to relatively low and high pressure loads. A control valve system controls the pressure levels of the low and high pressure flows, and relieves excess fluid from the high pressure flow to the low pressure flow to augment the low pressure flow.

Abstract: A combination shuttle and high pressure relief valve is provided within a hydrostatic drive or transmission system. The valve is constructed with a spool member in two sections. The sections include hooks that interact with one another to lock the spool sections together in one mode of operation, yet permitting the spool sections to act independently in another mode of operation. Complete fluid charging of the fluid system is ensured by dual flow circuitry between the system pump and motor, while a restrictor valve means is connected to the shuttle and pressure relief valve to provide continuous flow of fluid through a system filter.

Abstract: A fuel injection pump for diesel engines has a reciprocating pressure piston which also rotates to distribute fuel to the individual injection valves. At idling and low engine load, the duration of injection is extended by permitting part of the fuel advanced by the piston to flow back to the fuel storage compartment. The fuel control mechanism adjusts the piston stroke to compensate for this lost fuel, thereby extending the duration of injection and reducing engine noise.

Abstract: A helical screw air compressor unit has a rotary capacity control valve, a compressor inlet throttling valve, and a pressure relief valve for venting the compressor discharge conduit. A control circuit senses pressure in the compressed air supply system downstream of the compressor and operates the capacity control valve, inlet throttling valve, and pressure relief valve in a predetermined sequence to provide an improved power consumption characteristic for variable demand compressor applications. The control circuit includes a hydraulic control valve and an actuator for operating the rotary capacity control valve to regulate compressor throughput to maintain a predetermined pressure without overpressuring the supply system during operation at conditions of reduced demand for compressed air.