Abstract: A vacuum system and a method of operating a vacuum system. The system comprises a vacuum line, a pump, a pump motor, a pressure adjusting assembly, a pressure sensor and a control device. The pump is connected to the vacuum line for drawing fluids therefrom, and the motor is connected to the pump to drive the pump. The pressure adjusting assembly is connected to the vacuum line for conducting fluid into that line at an adjustable rate. The pressure sensor is connected to the vacuum line to generate a pressure signal representing the pressure in the vacuum line. The control device receives the pressure signal and generates a system control signal that is used to adjust the pressure in the vacuum line. The specific manner in which the pressure in the vacuum line is adjusted depends on the value of that pressure, and in particular, whether that pressure is in a first range or a second range.

Abstract: The invention is a constant flow pump control system that compensates for a change in gas flow rate that is caused by a change in the load resistance, by making the speed change inversely with the change in load resistance, desirably by sensing the change in pressure and changing speed by an amount related to the pump performance characteristic that is required to restore the flow rate to its selected value. In a preferred embodiment the system includes a closed loop pump speed control in which a selected flow rate reference is combined with a pressure feedback to provide an inverse change in the pump speed reference function or a direct change in the motor speed feedback function to compensate for the change in flow rate caused by a change in flow resistance.

Abstract: A fuel injection pump has a housing (3) with a flange (5) and a bore (40) in which are arranged a sleeve (2) and a pump piston (1). A valve body (4) with a hollow core space (20) is located in an axial end portion of the sleeve (2). The valve body (4) has at both axial end portions (11, 12) hydraulic dampening means. In the zone of the top dead center of the pump piston (1), its head (13) cooperates directly with the axial end portion (11) of the valve body (4), actuating a valve seat (27). This valve seat (27) located between the valve body (4) and the sleeve (2) acts as a fuel intake and relief valve for the fuel delivery system. A fluid spring including a cylinder chamber (42) and an additional piston (44), as well as an actuating element (19), are located adjacent an axial end of the pump piston (1 ). The actuating element (19) is linked with a drive.

Abstract: A fuel pumping apparatus for supplying fuel to an internal combustion engine comprises a rotary distributor member mounting a pumping plunger slidable in a bore and moved inwardly to discharge fuel from the bore by cam lobes on the internal surface of a cam ring, the cam lobes acting on the plunger through a cam follower. A valve is provided which at a predetermined position during the inward movement of the plunger, is opened to lower the pressure in the bore and thereby to terminate fuel flow through an outlet. The valve is actuated by the cam lobes either from the cam follower or from the plunger.

Abstract: A gas lock breaker for oil well pumps includes a stationary barrel with a standing valve on the bottom, a reciprocating piston in the barrel with a traveling valve on the bottom of the piston, an unseating rod positioned above the standing valve and adapted to protrude into the traveling valve to unseat the ball closure thereof near the bottom extremity of the downstroke of the piston. For a conventional well of any normal depth equipped with a pump jack for piston displacement anywhere in the range of 1 to 5 meters (3.3 to 16.4 feet), the unseating rod protrudes through the traveling valve a distance of about 1 to 15 percent of the piston stroke, or about 5 to 13 cm. (2 to 5 in.). The standing valve cage is preferably 12 to 20 cm. (4.75 to 8.0 in.), and the traveling valve is set to approach within 15 to 30 cm. (6 to 12 in.) of the standing valve.

Abstract: Air entrained in a pumped liquid is released from a pumping chamber operated by a single piston and having an outlet passage controlled by a back-seating valve biased closed by a spring, when the piston near the end of its compression stroke causes positive mechanical engagement to open the outlet valve.

Abstract: A reciprocatory piston and cylinder machine particularly suitable for use as a vacuum pump includes a cylinder (17), a cylindrical piston (16) relatively slidably reciprocable within the cylinder (17), and means for substantially sealing the annular space between the piston (16) and cylinder (17) in lieu of oil or other liquid lubricant. The sealing means comprises a sleeve (102) of a low-friction material disposed under circumferential tension, and preferably also under longitudinal tension, on the cylindrical surface of the piston (16). Also disclosed is a reciprocatory piston and cylinder machine of particular prior construction having a one-way valve (42) in an exhaust port (30) ahead of a head portion (24) of the piston (16). The arrangement is such that, as the front face of the piston head portion (24) approaches the closed cylinder end (52), the piston head portion 24 physically moves the one-way valve (42) so as to open the exhaust port (30).

Abstract: The metering device for a liquid medium comprises a cylinder and a piston operatively disposed therein to define a metering chamber ahead of the piston. The outlet end of the cylinder is open and closed by check valve means. The piston is driven forwardly through a working stroke to force the liquid medium in the metering chamber out of the chamber and past the check valve means. The piston breaks the plane of the open end of the cylinder on each working stroke to preclude entrapment of air in the metering chamber and thus provide for more accurate metering.

Abstract: The metering device for a liquid medium comprises a cylinder and a piston operatively disposed therein to define a metering chamber ahead of the piston. The outlet end of the cylinder is open and closed by check valve means. The piston is driven forwardly through a working stroke to force the liquid medium in the metering chamber out of the chamber and past the check valve means. The piston breaks the plane of the open end of the cylinder on each working stroke to preclude entrapment of air in the metering chamber and thus provide for more accurate metering.

Abstract: A pump for feed-pumps of fuel injection systems for internal combustion engines having a manually actuatable element, which operates counter to the force of a restoring spring to effect an inward stroke of a piston which includes a valve tappet thereon that pushes open a ball valve to the fuel feeding system of a feed pump. In operation, a medium is positively displaced from a work chamber into the feeding system. Upon an automatic return stroke of the piston, a medium is aspirated from the fuel feeding system of the feed pump into the work cylinder and at the end of the return stroke the ball valve closes automatically. In its position of repose, the pump does not require its piston to be locked in place, and pressure impacts of the feed pump are prevented from reaching the piston.

Abstract: The hydraulic tool of this invention includes a pressure chamber into which a fluid is pumped. A pump chamber has an inlet port and outlet port at opposite ends thereof and a pump plunger extends into the chamber with an annular space around it. An annular shoulder is provided on either the chamber or the plunger and a seal ring or sleeve fits slidably on the other component to seal against the shoulder. A spring biases the seal ring against the shoulder, and when the pump is extended to force fluid out the outlet port, the pressure in the chamber augments the spring force. Then, when the rod is retracted to create a void, fluid in the reservoir forces the seal ring or sleeve away from the seat surface to enter the inlet port.

Abstract: A reciprocatory piston and cylinder machine particularly suitable for use as a vacuum pump includes a cylinder (17), a cylindrical piston (16) relatively slidably reciprocable within the cylinder (17), and means for substantially sealing the annular space between the piston (16) and cylinder (17) in lieu of oil or other liquid lubricant. The sealing means comprises a sleeve (102) of a low-friction material disposed under circumferential tension, and preferably also under longitudinal tension, on the cylindrical surface of the piston (16). Also disclosed is a reciprocatory differential piston and cylinder machine of particular prior construction having a one-way valve (42) in an exhaust port (30) ahead of a head portion (24) of the piston (16). The arrangement is such that, as the front face (28) of the piston head portion (24) approaches the cylinder end face (52), the front face (28) physically moves the one-way valve (42) so as to open the exhaust port (30).

Abstract: A reciprocating pump for delivering cutting fluid to the machining situs between a tool and a workpiece includes a collapsible piston which forms a substantial seal in the pump during the power stroke and then collapses during the relaxation stroke to allow the piston to reassume its initial position in preparation for the next power stroke. The pump includes an indexer and switch which maintain the pump in an operative condition, thereby delivering cutting fluid to the machining situs for a predetermined amount of displacement between the tool and workpiece prior to engagement and subsequent thereto. The indexer and switch exploit a predetermined amount of play in the switch to maintain the pump in an operative condition for the desired time.

Abstract: A device for precise metering of liquids for intravenous delivery to a patient, the device including a pumping chamber with a reciprocable diaphragm positioned therein. The device also includes check valves positioned at the pumping chamber inlet and outlet, and a gas retention chamber located upstream of the pumping chamber and having an upper portion providing for the formation of a gas-liquid interface and a lower portion from which liquid free of gas bubbles may be removed and directed into the pumping chamber.

Abstract: A device for precise metering of liquids for intravenous delivery to a patient, the device including a pumping chamber with a reciprocable diaphragm positioned therein. The device also includes valves positioned at the pumping chamber inlet and outlet, the valve at the pumping chamber inlet being operated independently of the pressure within the pumping chamber. The device also includes a gas retention chamber having an upper portion providing for the formation of the gas-liquid interface and a lower portion from which liquid free of gas bubbles may be removed.

Abstract: In connection with a land clearing saw, a sapling control substance dispensing device comprising a container for the sapling control substance, a control substance nozzle and a control substance duct leading from the container to the nozzle, this duct incorporating a manually operable valve (1) comprising a piston (4) provided with return spring (11) and a cylinder (5), with ports for the control substance entry duct (6) and exit duct (7), these ducts being provided with check valves (8,18). Within the piston has been installed an auxiliary piston (14) loaded with a spring (16) and which as the piston (4) is being moved opens or closes a needle valve (9) associated with the exit duct port.

Abstract: A pipe section with an exteriorally secured valve body is arranged to be inserted in a lower portion of a well pipe string containing sucker rods and a lower pump, the pipe section and valve body being disposed slightly above the pump itself. A lateral pin passes through a connecting bore between the pipe section and valve body and is arranged to be urged in a lateral direction to operate the valve when the sucker rods are moved beyond their normal stroke within the pipe string. Opening of the valve serves to place the column of fluid in the well pipe string into communication with the well annulus and thereby permit emptying the pipe string of the fluid column and thus permitting the pipe to be pulled for repairing the pump or for other operations without the disadvantage of the heavy hydrostatic pressure resulting from the fluid column.

Abstract: A specially designed valve is incorporated in the pumping tube of an oil well pump secured to the lower end of an oil well pipe string. In pumping the well, oil is drawn up through the pumping tube and oil pipe string to the surface. The check valve is arranged to be actuated from the surface of the well in response to lowering the sucker rods for operating the pump beyond the normal amplitude limits to thereby place into communication the oil in the pumping tube and pipe string with the annulus of the well between the well casing and exterior walls of the pumping tube pipe string thereby equalizing the hydrostatic pressure and permitting pulling of the well pipe for pump servicing or other operations.

Abstract: A device for modifying a shock absorber so that the preload of the shock absorber spring may be adjusted. The device has a chamber member having a cylindrical inner member with an inside diameter slightly larger than the outside diameter of the shock absorber body. The chamber also has a cylindrical outer member sealingly attached at the upper end to the inner member. A piston is slidingly positioned in the chamber between the outer and inner cylinders and the piston forms a seat for the shock absorber spring. Hydraulic fluid is pumped into the chamber and by the addition of hydraulic fluid the spring of the shock absorber is compressed and the amount of preload between the shock absorber's relatively moveable parts is thereby increased.

Abstract: An hydraulic pump comprising a plunger slidingly located within a housing. A first valve is adapted to allow fluid to be drawn from a reservoir into the housing during movement of the plunger in one direction, and a second valve is adapted to allow fluid to flow from the housing during the greater part of movement of the plunger in its other direction. A control apparatus is provided to control the second valve at or near the completion of the plunger's movement in the mentioned other direction to allow fluid to move back through the second valve and into the reservoir.

Abstract: This invention relates to liquid metering pumps and according to the invention such a pump comprises a cylinder permanently connected to an inlet passage for the liquid and in which said cylinder a plunger piston is arranged to slide said piston co-operating with a sealing gland on the inlet side. The piston is urged by an elastic member into contact with a reciprocable actuating rod which co-operates with a sealing gland on the outlet side. The two sealing glands are separated by a spacer to form an annular chamber around the plunger piston and the actuating rod.

Abstract: An automatic pressure valve primarily intended for use in compressors comprising a closing element in the form of a plate, a valve seat with a valve seat face, springs and a stop, the closing plate being so situated in the closed state of the valve that the face of the plate at the cylinder side is below the outer dead center position of the piston. In its top position, the closing element forms with the valve seat face a toroidal shaped gap which in axial section is similar in shape to a De Laval nozzle. The closing element is moved to its lower position, namely into contact with the valve seat face by lowering of the piston on which it rests.