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| Number | Title | Issue Date |
| 8011289 | Half-sleeved and sleeveless plastic piston pumps In one aspect, a brake pump assembly with a hydraulic block and a pumping element including a polymer piston that is received in a piston bore. A circumference of the polymer piston defines a high-pressure seal slideably engaging adjacent structure. The polymer pist... | 09/06/2011 |
| 6960195 | Metering receptacle A metering receptacle has an elongate hollow body which at one end has a closable exit opening, and which at the other end is closable by way of a plastic plunger stopper. The plunger stopper is at the same time longitudinally displaceable in the hollow body by way ... | 11/01/2005 |
| 5865091 | Piston assembly for stirling engine A piston assembly for a double-acting engine such as a double-acting Stirling engine. A pair of sealing rings located on opposite sides of a sealing washer are positioned between a base section and a dome section of a piston head. These sealing rings are ... | 02/02/1999 |
| 5618169 | Water well pump cylinder components Water well pump plunger efficiency is improved by providing a pair of upwardly open outwardly flared wall cups surrounding a pump plunger and supported in superposed relation by a sleeve in the lowermost cup. A fluid passageway through the base of the upp... | 04/08/1997 |
| 5363744 | Accumulator piston having multiple elastomeric seals An accumulator piston is formed as a two-piece plastic molding for simplifying its construction and for cost reduction and weight reduction purposes. The piston has a radially stepped construction in which each step includes a radial flange carrying an an... | 11/15/1994 |
| 5303637 | Piston assembly structure for an hydraulic cylinder Portable lift structure for moving a support platform between a comparatively dry position above the surrounding deck of a liquid spa tank to a wetting position in the spa tank including two longitudinally extending structural members pivotally connected ... | 04/19/1994 |
| 5271313 | Position-controlled actuator A position-controlled actuator including a double acting pneumatic actuator, a selector valve which causes function of the actuator, a comparator which controls the action of the selector valve in response to a comparison between an input signal and a sig... | 12/21/1993 |
| 4771675 | Swabbing apparatus A swabbing apparatus has a plurality of swab cups molded on a single core, with at least two swab cups having a different fluid load carrying capacity, so that the swabbing apparatus will have a relatively broad fluid load carrying capacity. Each swab cup... | 09/20/1988 |
| 4770085 | Hydraulic jack A hydraulic jack includes a body (1) with front (2) and rear (3) covers and a rod (4) moving relative to said body (1) and having at least one projection made therein and mounting an additional member (7) and at least two grooves which form the respective... | 09/13/1988 |
| 4751870 | Seals for gas and oil well swabs Seal for maintaining gas-tight contact between casing wall and, particularly, automatic well swabs. The seal includes an upper portion containing a reinforcing tube and being minimally less in diameter than the casing interior, a tapering midsection and a... | 06/21/1988 |
| 4528896 | Dynamic seals for gas and oil well swabs Gas and oil well swabs, particularly a dynamic seal for maintaining gas-tight contact between the moving swab and the well casing. The seal includes a reinforcing tube and a flexible annulus having an upper throat portion complementally engaging the exter... | 07/16/1985 |
| 4452370 | Bottom closure for container A piston-shaped bottom closure for a hollow container has a closing member arranged so that when the closure is inserted into a container the closing member extends transversely of an inner wall of the container, a hollow guiding member extending from the... | 06/05/1984 |
| 4329916 | Packer nose assembly A packer nose assembly for pumping downhole equipment of the free type into and out of a tubing string located within a borehole. The assembly includes a mandrel having a lower end portion attachable to the downhole equipment and an upper end portion term... | 05/18/1982 |
