Abstract: First and second pistons are mounted to a common shaft which reciprocates during compression and suction strokes. During each of the strokes, fluid is pumped out at an outlet, via a one-way valve on the second piston. The one-way valve is opened or closed depending on whether the first and second pistons are in the compression or suction stroke. Additionally, pressure from the outlet assists in traversing the first and second pistons in the compression stroke. During the suction stroke, the fluid pressure applies a force on the first piston to counteract the fluid pressure on the second piston so that a smaller spring may be used. The size requirements of the solenoid and spring are reduced. Additionally, the fluid pump provides lower pressure spikes, since fluid is pumped out during both the compression and suction strokes and also provides a more even flow of fluid.

Abstract: A method of controlling a gear pump comprising two meshing gear wheels (11, 12), wherein the two gear wheels (11, 12) are driven via respective shafts (2, 3) each by a drive unit (7, 8). A current position of the one gear wheel (11, 12) is determined with respect to the current position of the other gear wheel (12, 11), and the current position of the one gear wheel (11, 12) is continuously adjusted with respect to the current position of the other gear wheel (12, 11) according to specified predefined operating conditions.

Abstract: A supercharged internal combustion engine including a pressurized fluid outlet, the engine comprising a two-ended piston, with one end received in a combustion chamber, and another end received in a hydraulic chamber. The piston further including a portion intermediate the two ends and received within an air chamber, and the air chamber has an air outlet communicating with a combustion air inlet to the combustion chamber.

Abstract: A dual-direction pump includes two cylinders arranged on opposite sides of a head portion and an inlet return-flow prevention device and a leakproof device mounted between the cylinder and the head portion for avoiding leakage at the juncture between the cylinder and the head portion or leakage induced by reverse flow in one of the cylinders in the case of a single-sided pumping operation in the other cylinder. The head portion has an outlet port to which an outlet return-flow prevention device is mounted. A knob is rotatably mounted to the outlet pot and a nut is fixed to the knob for selectively engaging an inflation valve to avert detachment. The outlet return-flow prevention device prevents reverse or return flow induced in the outlet port in order to reduce resistance caused thereby and enhances pumping efficiency.

Abstract: A pump includes a cylinder, a piston assembly, a first nozzle, a valve, a controller, a ring and a second nozzle. The cylinder defines first and second chambers and first and second channels for communication between the chambers. The piston assembly is received in the first chamber. The first nozzle defines a channel. The valve is received in the first chamber. The controller defines an axial channel and a radial channel communicated with the axial channel, and is received in the second chamber and linked to the valve through the second channel. The controller is movable between a first position for allowing the valve to seal the second channel and a second position for driving the valve to open the second channel. The ring is mounted on the controller so as to divide the second chamber into a first portion for communication between the first channel and the channel of the first nozzle and a second portion for communication between the second channel and the radial channel of the controller.

Abstract: The dual stage, dual mode air pump is selectively operable in a low pressure, high volume mode or a high pressure, low volume mode. It includes a pump head, an outer tube that is engaged to the pump head, an inner tube that is engaged to the pump head and a middle tube that is slidably engaged to both the outer tube and the inner tube. A mode pump switch is utilized to allow the pump operator to change the mode of the pump. In the preferred embodiment, the mode switch is disposed within the pump head. It includes an air passageway having a manually switchable valve disposed therein. In the high volume, low pressure mode the valve switch is closed, whereupon pumped air passes into a pneumatic article engaged to the end of the pump. When the valve switch is opened, the pump is operable in the low volume high pressure mode, and a portion of the pumped air is outletted into the ambient environment, rather than being pumped into the pneumatic article.

Abstract: A hydraulic oil well pump drive system for driving an oil well sucker rod includes a master piston positioned within a master cylinder for axial displacement between first and second ends of the master cylinder. The master piston has a piston drive rod which extends through one end of the master cylinder. The drive rod is connected to a crank pin of an eccentric crank. A center seal assembly divides the master cylinder into a working chamber and a pressure chamber in opposite ends of the master cylinder. Each respective chamber defines a fluid volume which varies with the displacement of the master piston. The master piston displacement creates a bi-directional flow of working fluid from the working chamber. A wellhead hydraulic assembly is operably connected to the oil well sucker rod and is in fluid communication with the master cylinder working chamber to receive the working fluid flow.

Abstract: A precision metering, multiple fluid pumping system comprised of a main pump for pumping a primary fluid and an auxiliary pump for pumping a secondary fluid adjustably linked to work in unison with the main pump. The auxiliary pump is linked to the main pump through a rack and pinion gear system connected to an oscillating arm that operates the auxiliary pump simultaneously with the main pump. The auxiliary pump is infinitely adjustable over a selected range by varying the connecting point of the auxiliary pump to the oscillating arm. The connecting point is varied by a worm screw adjustment that provides precision adjustment and metering of a secondary fluid. The system also includes a clutch mechanism between the auxiliary pump oscillating arm and a rack and pinion gear system to disengage the auxiliary pump for priming.

Abstract: A precision metering, multiple fluid pumping system comprised of a main pump for pumping a primary fluid and an auxiliary pump for pumping a secondary fluid adjustably linked to work in unison with the main pump. The auxiliary pump is linked to the main pump through a rack and pinion gear system connected to an oscillating arm that operates the auxiliary pump simultaneously with the main pump. The auxiliary pump is infinitely adjustable over a selected range by varying the connecting point of the auxiliary pump to the oscillating arm. The connecting point is varied by a worm screw adjustment that provides precision adjustment and metering of a secondary fluid. The system also includes a clutch mechanism between the auxiliary pump oscillating arm and a rack and pinion gear system to disengage the auxiliary pump for priming.

Abstract: An oscillatory pump includes a cylinder (9) having normally-closed valves (10,13) of flexible material fixedly located at the inlet (A.sub.c) and outlet (B.sub.c) ends of the cylinder (9), and a piston (1) having an inlet (A.sub.p) and an outlet (B.sub.p). The piston (1) is reciprocatable within the cylinder (9) and is provided with a further valve (6) of flexible material movable with the piston (1) and located at the outlet end (B.sub.p) of the piston (1). The piston (1) is constructed to allow fluid to pass from an inlet chamber (C1) formed between the inlet valve (10) and the inlet end (A.sub.p) of the piston (1) to an outlet chamber (C2) formed between the further valve (6) and the outlet valve (13) in response of the piston (1) within the cylinder (9). The valve includes a valve seat having a generally conical first surface portion and a second surface portion located radially inwardly of the first surface portion and extending generally parallel to the axis of the first surface portion.