Wall Portion Comprises Plural Axially Aligned Flexible Elements Patents (Class 92/251)
  • Patent number: 8561523
    Abstract: A reciprocating pump including a piston is disclosed. In some embodiments, the piston includes an annular hub, a flexible sealing element coupled to an outer surface of the hub, and a sleeve seated on the outer surface of the hub adjacent the sealing element. The sleeve is axially moveable relative to the hub to compress the sealing element. The sealing element includes a lip, which is displaced radially outward when the sleeve compresses the sealing element.
    Type: Grant
    Filed: April 23, 2008
    Date of Patent: October 22, 2013
    Assignee: National Oilwell Varco, L.P.
    Inventors: Andrew Dale Riley, Randall Ferrain Weaver
  • Patent number: 7685929
    Abstract: The present invention provides a telescopic hoist comprising a series of telescopically arranged tubular sections wherein the tubular sections are made in nitrided steel.
    Type: Grant
    Filed: January 6, 2004
    Date of Patent: March 30, 2010
    Assignee: Industries Mailhot Inc.
    Inventor: Luc Mainville
  • Patent number: 6938538
    Abstract: A bore seal telescopic hoist is formed of a series of telescopically arranged tubular sections each having a circumferential reservoir. A circumferential wiper is lodged in the reservoir and is used to collect debris or dirt which may be present on the inner wall of an adjacent tubular section.
    Type: Grant
    Filed: June 22, 2000
    Date of Patent: September 6, 2005
    Assignee: Industries Mailhot Inc.
    Inventor: Luc Mainville
  • Patent number: 6212998
    Abstract: A design for a packing assembly for a reciprocating piston pump is shown which allows for tighter tolerancing and increased packing life.
    Type: Grant
    Filed: December 21, 1998
    Date of Patent: April 10, 2001
    Assignee: Graco Minnesota Inc.
    Inventors: David J. Thompson, Thomas D. Lindblom
  • Patent number: 6186747
    Abstract: An axial plunger slurry pump comprises a pump body, a sloping cam plate, a swashplate, cylinders, plungers and a pump head. Each of the plungers comprises a plunger body with a rubber piston positioned in its front end and being able to slide over it, and an oil receiving gap communicating with an oil passage disposed between two facing end surfaces of the plunger body and the rubber piston. There are check valves each of which is provided in an oil passage between a ball of each of two-ball links, which ball is coupled with the swashplate, and the swashplate. Each of the cylinder and the plunger body are fitted together by means of a half-and-half locating pad, a cylinder sleeve, a pressing cap, and a locking device. The pump may be used widely in drilling, electric power, mine, building, and metallurgy, etc., for conveying mud, mortar, ore pulp, coal pulp, concrete, etc.
    Type: Grant
    Filed: July 6, 1999
    Date of Patent: February 13, 2001
    Inventors: Haiwei Zhou, Xuming Yin
  • Patent number: 5293811
    Abstract: A control fin actuator (28) for a guided missile (20) includes a pressure actuator (40) having a slidable piston (44) inside a housing (42). Rolling diaphragm seals (50, 56) of the top piston face (46) and the bottom piston face (48) to the inside wall of the housing (42) divide the interior of the housing (42) into at least two chambers (54, 58). The rolling diaphragm seals (50, 56) eliminate sliding friction as the piston (44) moves within the housing. The two chambers (54, 58) are controllably pressurized to slide the piston (44) within the housing (42), thereby moving a push rod (78) attached to the piston (44) and extending out of the housing (42). The push rod (78) is connected to a missile control fin output shaft (24) by a taut band connector (80) that avoids backlash. A magnet (86) may be positioned adjacent to the push rod (78) to induce eddy currents in the push rod (78), thereby providing a damping force that increases with increasing rate of movement.
    Type: Grant
    Filed: August 2, 1991
    Date of Patent: March 15, 1994
    Assignee: Hughes Aircraft Company
    Inventors: Charles M. DeLair, Russell B. Cline
  • Patent number: 4735129
    Abstract: Disclosed is a single acting mud pump piston assembly adapted for use in a mud pump mechanism including a piston and having an end portion with a shoulder reciprocatingly mounted in a cylinder. The assembly includes a circular flange mounted on the end portion in abuttment with the shoulder. A hub is removably mounted on the end portion in abuttment with the flange. A piston cap is mounted about the hub in abuttment with the flange. The assembly is held together by a washer and a nut engaging the end portion.
    Type: Grant
    Filed: June 3, 1983
    Date of Patent: April 5, 1988
    Assignee: Chromium Corporation
    Inventor: James G. Sjoberg
  • Patent number: 4697992
    Abstract: A refrigerant compressor includes a piston with two circumferential grooves on the outer surface of the piston, one of the grooves being located near the top and the other near the bottom. Conical piston rings made of plastic are disposed in the grooves. The piston rings, which have an outer diameter greater than that of the piston, have a curved surface shaped so that the outer diameter of the curved surface at one axial end of the piston ring is smaller than that at the other axial end. This unique arrangement of the curved conical seals reduces the loss of horsepower in motor driven refrigerant compressors by providing improved sealing between the piston and cylinder.
    Type: Grant
    Filed: February 12, 1986
    Date of Patent: October 6, 1987
    Assignee: Sanden Corporation
    Inventors: Hideharu Hatakeyama, Hidenao Takahashi
  • Patent number: 4598630
    Abstract: A double action slurry pump is provided having a shelf-flushing piston assembly mounted in a mating cylinder. The piston assembly includes a first piston having a peripheral sealing means and a reciprocating piston rod for driving the first piston. Second and third power pistons mounted adjacent opposite sides of the first piston include sealing discs and form respective first and second chambers with the first piston and the adjacent cylinder wall. The second and third power pistons serve to pump the slurry on the sides opposite the flushing fluid chambers. Each of the pumping pistons includes hollow carriers that cooperate with shoulders fixed to the piston rod to provide limited lost motion movement. The resulting lost motion serves to vary the size of the first and second chambers. During the stroke of the piston assembly in one direction, feed lines in the piston rod provide flushing fluid to the expanding second chamber.
    Type: Grant
    Filed: April 24, 1985
    Date of Patent: July 8, 1986
    Assignee: University of KY Research Foundation
    Inventor: David T. Kao
  • Patent number: 4594055
    Abstract: A piston assembly for a reciprocating piston type compressor includes a piston slidably disposed within aluminum alloy cylinders. The pistons have two annular grooves provided toward opposite ends on their outer peripheral surfaces. A conical shaped piston ring formed of resin and having an outer diameter larger than the outer diameter of the piston is disposed in each groove. The conical shaped piston ring creates a gap between the piston and cylinder to prevent direct contact between the piston and cylinder to thereby avoid abnormal wearing while effectively maintaining the flow of lubricating oil from the cylindrical chamber to the crank chamber.
    Type: Grant
    Filed: December 20, 1984
    Date of Patent: June 10, 1986
    Assignee: Sanden Corporation
    Inventors: Hideharu Hatakeyama, Hidenao Takahashi
  • Patent number: 4476771
    Abstract: A slurry pump is provided having a self-flushing piston assembly mounted in a mating cylinder. The piston assembly includes a first piston having a peripheral sealing member and a reciprocating piston rod for driving the first piston for pumping action. A second piston mounted adjacent to the first piston includes a sealing member and forms an enclosed chamber with the first piston. A lost motion coupler connects the pistons together and varies the size of the chamber. On the return stroke of the piston assembly, flushing liquid on the non-slurry side is sucked into the chamber as the chamber expands. On the power stroke, the flushing liquid is forced past the second sealing member to remove slurry particles and prevent wear of the cylinder. The disc on the first piston has sufficient flexibility to allow filling of the chamber and an accumulator is provided to control the back pressure after the chamber has been filled on the return stroke.
    Type: Grant
    Filed: September 30, 1982
    Date of Patent: October 16, 1984
    Assignee: University of Kentucky Research Foundation
    Inventor: David T. Kao
  • Patent number: 4346903
    Abstract: A high-pressure seal having a dynamic seal ring and a static seal ring supported by a backup ring is improved upon such that support ring is a one-piece construction having sealing chambers respectively defined together with the bore wall of the cylinder with the piston recess for the dynamic and static seal rings. The seal chamber for the static seal ring is formed to induce a stretching of this ring when the high-pressure seal is assembled in place, whereby the seal between the piston and cylinder is improved as the static seal ring is stretched to provide a tight seal between the backup ring and the piston.
    Type: Grant
    Filed: March 18, 1981
    Date of Patent: August 31, 1982
    Assignee: Klockner-Werke AG
    Inventor: Siegfried Heiermann
  • Patent number: 4294164
    Abstract: A piston for use in pneumatically operated piston-cylinder apparatus has a disc-shaped steel core for connection with a piston rod, a sealing ring of resilient material surrounding the core and having an integral sealing lip extending from each axial end an incomplete guide ring fitted around the sealing ring. The guide ring is formed of a graphite-filled plastics material and embraces a circumferential surface of the sealing ring to be axially fixed but radially resilient relative to the piston core.
    Type: Grant
    Filed: December 4, 1979
    Date of Patent: October 13, 1981
    Inventor: Kurt Stoll
  • Patent number: 4078810
    Abstract: A seal unit for movement through a flow conductor for pumpdown piston or well swab service, including a mandrel body, a seal element mounting sleeve disposed for limited travel on the body, and elastic annular seal means secured on the mounting sleeve to seal with the flow conductor wall in response to a first fluid differential across the unit and to permit controlled bypass and load transfer under a second higher differential. The seal means includes spaced annular lips or fins and an annular choke ring which is expanded by limited sleeve movement in response to a fluid pressure differential load applied across the fins. When the pressure differential across the fins exceeds a predetermined value, the sleeve expands the choke ring which assumes a major portion of the pressure differential load relieving the fins to reduce fin wear. As a pumpdown piston, the unit is pumped along a flow conductor to drive a tool train by fluid flow in a direction from the fins toward the choke ring.
    Type: Grant
    Filed: September 14, 1976
    Date of Patent: March 14, 1978
    Assignee: Otis Engineering Corporation
    Inventor: Henry P. Arendt