Abstract: A unitary packing especially suitable for use in pumps which transport liquids such as water-based solutions or suspensions includes a generally concave working face having an outer cylindrical annular flange, a generally convex opposed face preshaped for complementary overlying engagement with the working side of a pump piston. The packing, during use, is characterized by substantially reduced stresses and an extended life when compared with conventional packings. The packing may also be structured for occasional axial rotation with respect to the cylinder wall of the pump, which rotation may be enhanced by providing a force-directing element on the concave working face of the packing, this occasional rotation serving to circumferentially reorient the outer cylindrical annular flange of the packing with respect to the inner wall of the pump cylinder to thereby uniformly distribute wear caused by imperfections such as occlusions in the cylinder lining.

Abstract: A piston-cylinder arrangement comprising a cylinder member and piston means mounted slideably therein, the piston means comprising a piston member and a packing member mounted on the piston member for movement therewith, wherein said packing member has first and second axially spaced radially outer surfaces dimensioned such that each contacts slidingly against said cylinder wall and wherein the piston means comprises a lubricant reservoir in communication with the space between said surfaces, which space is substantially closed by said cylinder wall.

Abstract: A sealing device in a cylindrical or annular working chamber in hydraulic mechanisms consists of a disk or plug formed as a sealing ring holder and from such a deformable material that by the action of increasing hydraulic fluid pressure the material radially expands into completely sealingly contact with the chamber. The disk or plug is provided with a sealing ring for performing the sealing function before said pressure increase.

Abstract: An improved sealing structure for a pressure fluid cylinder of the type comprising a cylinder, a longitudinal slot in the cylinder, and a driver attached to a piston movable in the cylinder, the driver extending through the slot. The sealing structure includes a strip positioned to overlie the slot in the sealing relation, the strip extending into sealing contact with the inside surface of the cylinder on opposite sides of the slot. That inside surface area of the cylinder which the strip overlies in sealing relation is provided with a cross-sectional radius greater than the cross-sectional radius of that cylinder surface area not in contact with the strip. Preferably the strip is chamfered on its inside surface toward its edges so that the height of the opposed strip edges is no greater than 0.1 mm.

Abstract: A mud pump piston comprising an annular elastomeric ring having an annular circumferential surface defining an acute angle circumferential tip of relatively small area which engages the pump cylinder wall and an annular anti-extrusion ring connected to and displaceable with the elastomeric ring, the elastomeric ring being configurated to correspond with and rest against a dish shaped surface of the anti-extrusion ring presenting a bevelled or diagonal slope extending from the outside diameter (acute to the axis of the mud pump piston) spanning substantially more than half of the radial distance occupied by the annular elastomeric ring and the annular anti-extrusion ring, which diagonal surface merges with a flat surface normal to the axis of the mud pump piston whereby hydro-planing is reduced because of the increased unit pressure load on the small tip area, along a line contact, the tip is automatically wear compensating, friction is substantially reduced by reason of the smaller high pressure wipe area, lo

Abstract: A sleeve seal for sealing a front end of a piston and a cylinder wall wherein the front surface of the sleeve seal remote from the front end of the piston is provided with circular coaxial undulations.

Abstract: Improved brake actuators of the type having both service chamber and spring emergency-parking chambers utilizing piston in each said chamber (no diaphragms); improved double piston brake actuator wherein the service chamber is inboard of the spring emergency chamber; improved double piston brake actuator having an inboard spring emergency-parking and an outboard service chamber.

Abstract: A grease gun plunger of elastic material formed to provide a central hub, a peripheral skirt, and a web joining the skirt to said hub, the web being unitary with said hub at a first end of the plunger and with the skirt at a second end of the plunger to comprise a generally conical partition across the plunger. The skirt has an outer surface which tapers inwardly in both axial directions from a location of maximum outside diameter near the second end of the plunger. The plunger has a peripheral groove around said second end, said groove having a radial dimension substantially equal to the radial thickness of said skirt.

Abstract: The walls of the plunger (piston) of the fuel metering pump are relatively thin so that, when pressurized, they expand to provide more effective sealing. A plug is then used in the bore of the plunger to reduce its volume. In one embodiment the wall thickness in the portion of the plunger between the valving openings is further reduced to increase the wall expansion, and thus sealing, adjacent the valving openings. In some embodiments, ends of the members about the plunger are provided with skirts to decrease their tendency to expand, thus improving the sealing.

Abstract: To permit dry operation of a piston within the cylinder, the cylinder is made of metal, and the piston is made of polytetrafluorethylene; the piston, preferably, is formed with an annular ring groove extending downwardly from an end face thereof to leave a circumferential lip, the groove having a spring located therein biasing the lip outwardly against the cylinder wall, to provide for sealing contact of the lip against the cylinder wall, which is additionally reinforced by pressure of the gas being compressed by movement of the piston within the cylinder, tending to expand the lip against the piston surface, at the time when the compression is highest, and sealing is the most desired.

Abstract: The present invention concerns a piston for high pressure hydraulic machines. Said piston comprises a cylindrical body having at the periphery thereof a resiliently deformable cylindrical flange which, in use, forms a tight seal with the cylinder, the flange being integral with the piston body and forming, by means of its inner surface, a recess in the end face of the piston which is subjected to high pressure.

Abstract: A radial motor powered by pressurized gas is disclosed as used for starting the internal combustion engine of a portable implement such as a powered chain saw or lawn mower. The motor is designed for economical manufacture and assembly, durability, and economy of gas used. It includes pistons formed of stiff resilient material that in assembly are snapped onto the outer ends of connecting rods and held in place during operation of the motor without the use of retaining rings, pivot pins or screws. The inner ends of these connecting rods are held in sockets in connecting rod mounting means either by the shapes of the sockets or by the resilience of either or both of the connecting rod and mounting means. The motor includes a rotatable valve driven by a free end of the crankshaft to feed gas to the cylinders.

Abstract: A piston and seal assembly is adapted to work in a cylinder, particularly a master cylinder of a vehicle braking system, the seal having a lip which sealingly engages the cylinder bore on the pressure stroke, an inner portion mounted on the piston, and an interconnecting portion between the lip and the inner portion. A retaining member holds the seal on the piston and engages the interconnecting portion during the return stroke of the piston so that the seal flexes about the line of engagement between the retaining member and the interconnecting portion to provide a recuperation flow path between the lip and the cylinder bore.

Abstract: Improved brake actuators of the type having both service chamber and spring emergency-parking chambers utilizing piston in each said chamber (no diaphragms); improved double piston brake actuator wherein the service chamber is inboard of the spring emergency chamber; improved double piston brake actuator having an inboard spring emergency-parking and an outboard service chamber.

Abstract: A small high speed direct connected motor compressor has a unitary piston and piston rod whereby the piston wobbles in the cylinder as the crank shaft rotates. The wobbling piston is sealed to the cylinder by a flanged disk of Teflon which forms both a seal and mechanical guide for the piston and which runs without lubrication in contact with a low-friction, surface-coated cylinder of high heat conductivity. The circular rim of the Teflon cup is warped from circular outline to elliptical outline twice per revolution while maintaining its seal with the walls of the cylinder. The structure involves small clearance spaces with consequent good efficiency.