Abstract: A human-powered pump assembly includes a frame and a treadle pivot attached to the frame, such that the treadle pivot defines a horizontal rotational axis. The pump assembly includes a pair of treadles coupled to the treadle pivot and a rocker pivot attached to the frame, such that the rocker pivot defines a separate horizontal rotational axis. The pump assembly includes a reciprocating rocker coupled to the rocker pivot and to the pair of treadles to constrain the motion thereof, such that the rocker pivot axis is located below the treadle pivot axis.

Abstract: A modular pump system permits combining multiple discrete pump assemblies in serial and/or parallel configurations to tailor system output to user needs. The assemblies may be combined by hand quickly, without the needs for tools, to permit use in remote areas.

Abstract: A modular pump system permits combining multiple discrete pump assemblies in serial and/or parallel configurations to tailor system output to user needs. The assemblies may be combined by hand quickly, without the needs for tools, to permit use in remote areas.

Abstract: A human-powered pump assembly includes a frame and a treadle pivot attached to the frame, such that the treadle pivot defines a horizontal rotational axis. The pump assembly includes a pair of treadles coupled to the treadle pivot and a rocker pivot attached to the frame, such that the rocker pivot defines a separate horizontal rotational axis. The pump assembly includes a reciprocating rocker coupled to the rocker pivot and to the pair of treadles to constrain the motion thereof, such that the rocker pivot axis is located below the treadle pivot axis.

Abstract: A human-powered pump assembly includes a frame and a treadle pivot attached to the frame, such that the treadle pivot defines a horizontal rotational axis. The pump assembly includes a pair of treadles coupled to the treadle pivot and a rocker pivot attached to the frame, such that the rocker pivot defines a separate horizontal rotational axis. The pump assembly includes a reciprocating rocker coupled to the rocker pivot and to the pair of treadles to constrain the motion thereof, such that the rocker pivot axis is located below the treadle pivot axis.

Abstract: The invention relates to a double-acting pump system for use in moving a fluid. The pump system includes a means for inputting power at a location remote from the double-acting pump. The system allows for manual power input, such as through a local pumping unit. The double-acting pump may define an interior volume and include a first end chamber in fluid communication with the local pumping unit, a second end chamber in fluid communication with the local pumping unit, a central chamber having a separating section, and a driving element (e.g., a double-ended piston) slidably located within the interior volume of the double-acting pump. The separating section may include an inlet valve section (e.g., two inlet valves) and an outlet valve section (e.g., two outlet valves).

Abstract: A human-powered pump assembly includes a frame and a treadle pivot attached to the frame, such that the treadle pivot defines a horizontal rotational axis. The pump assembly includes a pair of treadles coupled to the treadle pivot and a rocker pivot attached to the frame, such that the rocker pivot defines a separate horizontal rotational axis. The pump assembly includes a reciprocating rocker coupled to the rocker pivot and to the pair of treadles to constrain the motion thereof, such that the rocker pivot axis is located below the treadle pivot axis.

Abstract: Provided herein is an innovative human powered pumping device comprising a piston and cylinder pumping mechanism that is hinged off a base. In use, the piston is driven in and out of the cylinder by a handle which is pushed and pulled by the operator. The base is resting on the ground and the cylinder is hinged off the base such that the pumping mechanism can rotate with respect to the base during the pumping motion.

Abstract: Provided herein are exemplary embodiments of an efficient pump apparatus. In one embodiment the pump apparatus comprises a piston assembly loosely disposed within a cylinder. The piston assembly includes a driving cable connecting a top leaky piston and a bottom leaky piston having a check valve connected thereto. The cylinder includes an outlet pipe at an upper portion thereof and a check valve located at a lower end of the cylinder. The pistons move in the cylinder at a velocity relative to the conduit such that as the pistons move along the cylinder they create a substantial tortuous leak path forming a hydrodynamic seal between the pistons and the cylinder.

Abstract: Apparatus and method for determining the level of particulate contamination within the fluid of a hydraulic system. System fluid is introduced through a non-return valve into a space where it is contained by a piston. The structure of the piston includes relatively-movable parts defining a restricted orifice to which fluid, having passed through a drilling in the piston, may escape to drain. When the piston is moved so as to tend to reduce the trapped volume, fluid is expelled from the volume through the drilling and clearance until the clearance becomes blocked by contaminants. The degree of contamination may then be derived from the distance that the piston has moved. The separate parts of piston structure are then relatively-moved to clear the orifice and allow the rest of the trapped fluid to escape, after which the orifice is reset and another volume of fluid introduced to be tested. The piston may be driven by reaction with the system fluid, or alternatively by means independent of that fluid.

Abstract: Apparatus and method for determining the level of particulate contamination within the fluid of a hydraulic system. System fluid is introduced through a non-return valve into a space where it is contained by a piston. The structure of the piston includes relatively-movable parts defining a restricted orifice to which fluid, having passed through a drilling in the piston, may escape to drain. When the piston is moved so as to tend to reduce the trapped volume, fluid is expelled from the volume through the drilling and clearance until the clearance becomes blocked by contaminants. The degree of contamination may then be derived from the distance that the piston has moved. The separate parts of piston structure are then relatively-moved to clear the orifice and allow the rest of the trapped fluid to escape, after which the orifice is reset and another volume of fluid introduced to be tested. The piston may be driven by reaction with the system fluid, or alternatively by means independent of that fluid.

Abstract: A device for determining the level of particulate contamination in a hydraulic system. Between the inlet and outlet of the device the fluid passes through the narrow clearance between a piston and a surrounding bore. As the clearance becomes obstructed by contaminant, pressure rises in a chamber upstream of the piston. Rise of this pressure above a certain level is detected by a detector which both triggers a counter and operates a solenoid to withdraw the piston and release trapped contaminant, after which the piston returns and another cycle of contaminant build-up begins. The frequency of the release of the piston indicates the degree of contamination of the fluid. Instead of pressure build-up, parameters related to fluid flow may be used to trigger the counter and the release of contaminants from clearance, and means may be provided to meter individual, fixed-volume charges from the general body of fluid and discharge them through a clearance.

Abstract: A high-pressure piston pump in which a low-viscosity working liquid supplied at a first pressure is delivered at a second, ultra-high pressure of, typically, up to 4,000 bars, for use in jet cutting and cleaning operations comprises a cylinder enclosing a first variable volume chamber for a viscous, operating liquid between a main piston and a subsidiary piston, and a second variable volume chamber for the working liquid, between the subsidiary piston and the head end of the cylinder. Operating liquid which leaks from the first chamber during working strokes of the pump and which thus reduces the volume of liquid in the first chamber, is replaced through a non-return valve in the main piston during non-working strokes as a result of the reduction in pressure in the first chamber. The subsidiary piston is provided with a coupling engageable with the main piston for limiting movement of the main piston away from the subsidiary piston during non-working strokes of the pump.