Having Varying Area Of Chamber Passageway For Thrust Member Patents (Class 188/288)
  • Patent number: 10670107
    Abstract: A hydraulic damper for a vehicle including a main tube. A first piston assembly is slideably disposed in the main tube and axially divides the main tube into a rebound chamber and a primary compression chamber. A hydraulic compression stop assembly is disposed in the primary compression chamber and includes a narrowed section extending between an open end and a closed end. A second piston assembly is slideably disposed in the narrowed section and is coupled with the first piston assembly. The second piston assembly has a piston tube that extends between an opened end and a shut end. A displaceable partition is slideably disposed in the piston tube. A first auxiliary compression chamber is defined between the partition and the closed end of the narrowed section. A second auxiliary compression chamber is defined between the partition and the shut end of the piston tube.
    Type: Grant
    Filed: December 15, 2017
    Date of Patent: June 2, 2020
    Assignee: BEIJINGWEST INDUSTRIES CO., LTD.
    Inventor: Piotr Andrzej Flacht
  • Patent number: 10603974
    Abstract: A damper assembly includes a main tube disposed on a center axis and defines a fluid chamber for containing a working fluid. A main piston is disposed in the fluid chamber dividing the fluid chamber into a rebound and a compression chamber. A piston rod is attached to the main piston for moving the main piston between a compression stroke and a rebound stroke. An additional piston is attached to the piston rod adjacent to the main piston. The additional piston includes a body having an upper and a lower member defining a groove. A sealing ring is disposed in the groove and being radially expandable in response to a working fluid pressure. The sealing ring includes at least one annular collar extending outwardly from the sealing ring for forming a locking engagement with the upper and lower members to limit the radial expansion of the sealing ring.
    Type: Grant
    Filed: September 21, 2018
    Date of Patent: March 31, 2020
    Assignee: BEIJINGWEST INDUSTRIES CO., LTD.
    Inventors: Dominik Kasprzyk, Piotr Grzegorz Maton, Pawel Edward Kus
  • Patent number: 10557515
    Abstract: A gas pressure spring comprising a housing having a gas-filled interior, a longitudinal axis, a closed housing end and an open housing end which is situated opposite the closed housing end. The gas pressure spring additionally includes a piston rod which is displaceable along the longitudinal axis and is guided out of the housing in a sealed manner through the open housing end, a piston unit which is fastened on the piston rod and a damping unit for damping the displacement of the piston unit.
    Type: Grant
    Filed: January 26, 2017
    Date of Patent: February 11, 2020
    Assignee: SUSPA GmbH
    Inventor: Siegfried Keller
  • Patent number: 9976542
    Abstract: A linear telescopic actuator (1) that comprises a cylinder (2), a sliding part (3), a spring seat (4) and a first compression spring (5) capable of resiliently opposing the sliding part (3) approaching the spring seat (4). The spring seat (4) presents an outer annular groove (6) and the cylinder (2) includes an inner annular groove (7). The actuator (1) also presents a blocking part (8), the actuator (1) being adapted to adopt selectively an assembled configuration and a disassembled configuration. The blocking part (8) in the assembled configuration is engaged inside the inner and outer annular grooves (6, 7). The blocking part (8) in the disassembled configuration being disengaged from one of the grooves so as to allow spring seat (4) to slide in the cylinder (2).
    Type: Grant
    Filed: August 24, 2016
    Date of Patent: May 22, 2018
    Assignee: SAFRAN LANDING SYSTEMS CANADA INC.
    Inventor: Gary Ataman
  • Patent number: 9416840
    Abstract: A gas spring for forming equipment, including a piston received at least partially in a cylinder for reciprocation between extended and retracted positions, and including a throttling passage disposed between the piston and the cylinder in fluid communication between first and second pressure chambers during at least a portion of the reciprocation of the piston. The throttling passage is of variable cross-sectional area, which varies with a length of the passage to at least partially restrict gas flow therethrough in a manner varying with return of the piston toward its extended position to decelerate the piston at a predetermined rate.
    Type: Grant
    Filed: January 23, 2012
    Date of Patent: August 16, 2016
    Assignee: DADCO, INC.
    Inventor: Jason L. Vandine
  • Patent number: 8955654
    Abstract: A vehicle shock absorber generates an additional counter-force acting counter to the direction of movement near the limit position of movement. The shock absorber substantially comprises a damping medium-filled damping cylinder that is divided into two damping chambers by a main piston. The main piston is axially moveable relative to the damping cylinder and is attached to a piston rod. A second piston/damping piston that contains one or more first and second through-ducts is mounted to the piston rod. The ducts are defined by first and second flow-limiting devices such as multiple thin washers. The damping piston slides in a restricting space located in the damping cylinder. The restricting space has an inside diameter smaller than the inside diameter of the damping cylinder. The additional counter-force is substantially constant throughout the entire stroke in order to create gentle braking of the damping movement.
    Type: Grant
    Filed: December 10, 2008
    Date of Patent: February 17, 2015
    Assignee: Ohlins Racing AB
    Inventors: Nils Göran Nygren, Magnus Danek, Johan Jarl
  • Patent number: 8857579
    Abstract: A shock absorber comprises a tubular housing (10), a cover (14), and a piston (34) defining within the tubular housing (10) a working chamber (W) 34g 34h and an accumulator chamber (A). A first fluid pathway (34p, 42, 34g) and a second fluid pathway (46, T, 34f) arranged in parallel connect the working chamber (W) to the accumulator chamber (A). The first fluid pathway establishes a permanent fluid communication between the working chamber (W) and the accumulator chamber (A). A valve assembly comprises an obturating element (44) arranged around the piston (34) and slidable along an axial length of the piston (34). The second fluid pathway comprises a first pathway section (34f) formed through the piston and a second pathway section (46, T) formed between the piston (34) and the obturating element (44). The second fluid pathway is able to selectively assume an open configuration and a closed configuration, and it has a lower fluid resistance than the fluid resistance of the first fluid pathway.
    Type: Grant
    Filed: October 13, 2010
    Date of Patent: October 14, 2014
    Assignee: Cultraro Automazione Engineering S.R.L.
    Inventor: Antonino Cultraro
  • Patent number: 8776965
    Abstract: A shock absorber that absorbs a vibration using a working fluid charged into a first chamber and a second chamber comprises a tube body, an inserted body, a tip end of which is inserted into the tube body from an end portion of the tube body, and a partition wall portion that is provided on the tip end of the inserted body to be capable of sliding within the tube body and partitions an interior of the tube body into the first chamber and the second chamber. The shock absorber comprises a connecting portion that is provided within a partition wall portion sliding region of the tube body and connects the first chamber and the second chamber when the partition wall portion passes thereby.
    Type: Grant
    Filed: June 21, 2010
    Date of Patent: July 15, 2014
    Assignee: Kayaba Industry Co., Ltd.
    Inventor: Nobuhiro Noguchi
  • Patent number: 8657086
    Abstract: An identical engagement hole 12b is formed in each of first and second brackets 1, 2. A first engagement portion 31c is formed in a damper body 31 of a rotary damper 3. A distal end portion of a rotor 32 of the rotary damper 3 is non-rotatably inserted in an adapter 4. A third engagement portion 46 is formed in an outer circumference of the adapter 4. The first engagement portion 31c is non-rotatably inserted in the engagement hole 12b of the first bracket 1. The third engagement portion 46 is non-rotatably inserted in the engagement hole 12b of the second bracket 2.
    Type: Grant
    Filed: May 11, 2011
    Date of Patent: February 25, 2014
    Assignee: Sugatsune Kogyo Co., Ltd.
    Inventor: Shinpei Iwata
  • Patent number: 8485326
    Abstract: In the inside of a cylinder tube, there are provided a piston chamber and an adjusting chamber communicating each other, and these both chambers are filled with oil in a pressurized condition, and further, there are provided a piston moving in an axial direction in the piston chamber and a rod coupled to the piston. An elastic member is located in the inside of the adjusting chamber in a state that a reservoir tank is formed in the adjusting chamber by being compressed by pressurizing force of the oil, and impact is absorbed in such a way that the elastic member is caused to extend and contract by the oil flowing in/flowing out the reservoir tank by movement of the rod.
    Type: Grant
    Filed: March 18, 2008
    Date of Patent: July 16, 2013
    Assignee: SMC Corporation
    Inventor: Eiko Miyasato
  • Patent number: 8479895
    Abstract: A vibration damper with stroke-dependent damping force includes a cylinder in which a piston rod with a piston is axially movable. The piston divides the cylinder into two work spaces filled with damping medium. A bypass between the work spaces is opened or closed depending on the piston position. The piston has a damping valve for at least one through-flow direction formed by a valve body that partially covers a through-flow channel in the damping valve. The valve body has first and second pressure-actuated surfaces on opposite sides of the valve body. The action of the second pressure-actuated surface depends on the position of the piston in relation to the bypass. The first pressure-actuated surface exerts a lifting force and the second pressure-actuated surface exerts a closing force on the valve disk. The second pressure-actuated surface is connected to a control space and a connection channel that overlaps with the bypass depending on the stroke position of the piston.
    Type: Grant
    Filed: March 16, 2011
    Date of Patent: July 9, 2013
    Assignee: ZF Friedrichshafen AG
    Inventors: Steffen Heyn, Bernd Zeissner
  • Patent number: 8448760
    Abstract: A buffering, energy absorbing, system has tapered grooves within either the inner surface of a cylindrical main body or along the sides of a piston head to allow fluid flow, where the tapered grooves increasingly or decreasingly restrict the flow of fluid between the inside of the main body and an accumulator.
    Type: Grant
    Filed: August 30, 2007
    Date of Patent: May 28, 2013
    Assignee: The United States of America as Represented by the Secretary of the Army
    Inventor: Gary J. Houtsma
  • Patent number: 8348028
    Abstract: In a pneumatic damper for slowing down movable furniture parts, comprising a cylinder and a piston movably disposed in the cylinder so as to form a displacement chamber at one side and a vacuum chamber at the other side of the piston, the piston includes a seal element which, in one end position thereof, is in close contact with the wall of the cylinder whose cross-section increases toward the opposite end of the cylinder so that the sealing effect collapses when the piston approaches its other end position and the piston includes a piston rod, which has a diameter of less than 35% of the piston diameter and sealingly extends through a cylinder end wall.
    Type: Grant
    Filed: September 26, 2005
    Date of Patent: January 8, 2013
    Inventors: Günther Zimmer, Martin Zimmer
  • Patent number: 8282086
    Abstract: There is provided a vibration isolator in which a restriction passage for causing a main fluid chamber and a sub-fluid chamber to communicate with each other is changed over to one of a first restriction passage and a second restriction passage according to a change in the frequency of vibrations in a short period of time, and the size of the isolator is made small efficiently. A plunger member 78 closes an orifice opening 74 when being moved to a closing position against the urging force of a coil spring 90 by the fluid pressure in a pressurization space 130, and opens the orifice opening 74 when being returned to an opening position by the urging force of the coil spring 90. For the orifice opening 74, the opening ratio R between the transverse opening width along the axial direction and the longitudinal opening width along the circumferential direction is set in the range of 2?R?25, further preferably 5?R?20.
    Type: Grant
    Filed: September 6, 2006
    Date of Patent: October 9, 2012
    Assignee: Bridgestone Corporation
    Inventor: Akira Ueki
  • Publication number: 20120247891
    Abstract: Provided is a shock absorber enabling stable stop by damping at a terminal of a stroke and covering demanded impact-absorbing models. The shock absorber has a piston chamber, a start part for piston movement, a decelerating part, and an end part for stopping the piston. The start part forms a curve to provide a diameter larger than a virtual tapered surface formed within a stroke range of the piston and to be outward to a central axis of the piston chamber. In the decelerating part, a variation of diameter reduction is increased with the result that the diameter becomes smaller than the tapered surface, and a curve is formed so the change in variation of diameter reduction reaches the maximum variation point and turns negative. In the end part, the variation of diameter reduction is decreased with the result that a curve which enables piston stopping by damping is formed.
    Type: Application
    Filed: March 12, 2012
    Publication date: October 4, 2012
    Applicant: SMC CORPORATION
    Inventors: Eiko MIYASATO, Masayuki Ishikawa, Tsuyoshi Mita, Akira Hiroki, Youji Takakuwa, Kouichi Matsuzaki, Toshio Minakuchi, Mariko Kessoku, Kodai Yoshinaga
  • Patent number: 8251376
    Abstract: A bicycle suspension includes a stroke adjustment unit, a suspension damper, a damper adjustment unit, and an electronic controller. The stroke adjustment unit is configured to adjust a stroke of the bicycle suspension, which is configured to expand and contract within the stroke. The suspension damper is configured to apply damping force to the bicycle suspension. The damper adjustment unit is configured to adjust the damping force applied by the suspension damper. The electronic controller is configured to control the stroke adjustment unit and the damper adjustment unit.
    Type: Grant
    Filed: July 17, 2009
    Date of Patent: August 28, 2012
    Assignee: Shimano Inc.
    Inventors: Seiji Mouri, Tsuyoshi Miyake
  • Publication number: 20120205208
    Abstract: A shock absorber comprises a tubular housing (10), a cover (14), and a piston (34) defining within the tubular housing (10) a working chamber (W) and an accumulator chamber (A). A first fluid pathway (34p, 42, 34g) and a second fluid pathway (46, T, 34f) arranged in parallel connect the working chamber (W) to the accumulator chamber (A). The first fluid pathway establishes a permanent fluid communication between the working chamber (W) and the accumulator chamber (A). A valve assembly comprises an obturating element (44) arranged around the piston (34) and slidable along an axial length of the piston (34). The second fluid pathway comprises a first pathway section (34f) formed through the piston and a second pathway section (46, T) formed between the piston (34) and the obturating element (44). The second fluid pathway is able to selectively assume an open configuration and a closed configuration, and it has a lower fluid resistance than the fluid resistance of the first fluid pathway.
    Type: Application
    Filed: October 13, 2010
    Publication date: August 16, 2012
    Inventor: Antonino Cultraro
  • Patent number: 8220602
    Abstract: Damping movement device of pieces of furniture which are movable relative to stationary parts. The device has a cylinder with a piston movable in a longitudinal direction, forming a modifiable working chamber filled with liquid medium. The liquid medium is transferred in a throttled manner. A piston rod is sealingly guided and connected to one side of the piston. The movement of the parts of furniture which is to be damped is transmitted to the piston via the outer end of the piston rod facing away from the piston. A volume compensating mechanism is provided. The piston rod is coupled to the piston with overflow ports. The non-return disk with overflow port is moved into sealing contact with the facing piston face. A spring biasing the facing faces of the non-return disk and the piston into the spaced-apart position is arranged between the non-return disk and the piston.
    Type: Grant
    Filed: June 9, 2005
    Date of Patent: July 17, 2012
    Assignee: Alfit AG
    Inventor: Guenter Grabher
  • Patent number: 8205729
    Abstract: A cylinder chamber filled with a liquid, a piston disposed inside the cylinder chamber, a piston rod connected to the piston, and an accumulator allowing the piston rod to generate a damping force by receiving the liquid from a compression side of the cylinder chamber are included, and on an internal periphery of the cylinder chamber, one line of a helical damping groove is formed within a stroke range of the piston, a groove width of the damping groove is constant over the entire length of the damping groove, a depth of the damping groove gradually decreases along a spiral toward the direction in which the piston rod is pushed in, and a length of the piston in a direction along the axis line is smaller than a pitch of the damping groove.
    Type: Grant
    Filed: June 23, 2008
    Date of Patent: June 26, 2012
    Assignee: SMC Corporation
    Inventors: Eiko Miyasato, Soichi Sato
  • Patent number: 8162112
    Abstract: Methods and apparatus for accommodating vehicle suspensions that may bottom out. Some embodiments of the present invention include the secondary shock absorber placed within a primary shock absorber. Yet clear embodiments describe a shock absorber having multiple fluid flowpaths during compression, with one of the flowpaths being active near the bottoming-out condition.
    Type: Grant
    Filed: February 11, 2008
    Date of Patent: April 24, 2012
    Assignee: Competition Tire East
    Inventors: Bill J. Gartner, Andrew Benjamin Lambert
  • Publication number: 20120090931
    Abstract: A hydraulic shock absorber comprising a main tube divided, by a piston-rod extending through the extension chamber. The shock absorber is further provided with a hydraulic rebound stop, called HRS fixed in the extension chamber and comprising a HRS-tube restricting the main tube, bottom and an 10 entry. The HRS also has HRS-piston freely slidably mounted on the rod and having a diameter adjusted to the HRS-tube and being provided with at least one fluid-passage substantially axially oriented. The axial displacements of the HRS-piston are limited between a Rebound-stop and a HRS-ring, both fixed to the rod. The fluid-passage is open to a flow of fluid when in abutment against the HRS-ring and being sealed when in abutment against the Rebound-stop.
    Type: Application
    Filed: October 15, 2010
    Publication date: April 19, 2012
    Inventors: Olaf Krazewski, Waldemar Widla, Pawel Slusarczyk
  • Patent number: 8157064
    Abstract: Disclosed is a shock absorber for a drawer. The shock absorber includes a body filled with fluid, a piston member inserted into the body while being coupled with a rod, and a buffering member installed in the body to prevent the body from being broken by receiving pressure change of fluid when the piston member moves forward and backward. According to the shock absorber, high impact force generated when the drawer is closed can be absorbed and efficiently distributed, so that the drawer can be silently operated.
    Type: Grant
    Filed: May 29, 2008
    Date of Patent: April 17, 2012
    Assignee: Moonju Hardware Co., Ltd.
    Inventor: Jaehong Kim
  • Publication number: 20120061194
    Abstract: A shock absorber includes: a working tube having a first internal diameter portion and a second internal diameter portion, an internal diameter of which is smaller than an internal diameter of the first internal diameter portion; a piston valve having an external diameter corresponding to the internal diameter of the first internal diameter portion and sliding along the inner surface of the first internal diameter portion; and a damping piston having an external diameter corresponding to the internal diameter of the second internal diameter portion and sliding along the inner surface of the second internal diameter portion. The second internal diameter portion is disposed at a lower portion of the working tube, such that it interacts with the damping piston when a full bump of the shock absorber occurs. The second internal diameter portion includes a slit that is formed in a longitudinal direction and faces the damping piston.
    Type: Application
    Filed: September 7, 2011
    Publication date: March 15, 2012
    Inventor: Chun Sung YU
  • Patent number: 7565956
    Abstract: A shock absorber has an outer tube, an inner tub, a piston rod, a piston and a damping device. The inner tube is slidably inserted into the outer tube and has an inner space with an inner diameter. The piston is securely mounted on the piston rod, is slidably held inside the inner tube to divide the inner space of the inner tube into two segments and has at least one channel. The damping device has a plug and a sleeve. The plug is securely attached to the piston and has a diameter. The sleeve is securely mounted in the inner tube and has an inner diameter. The diameter of the plug is smaller than the inner diameters of the inner tube and the sleeve. The inner diameter of the sleeve is smaller than that of the inner tube.
    Type: Grant
    Filed: July 25, 2006
    Date of Patent: July 28, 2009
    Inventors: Chung-Chia Lee, Chung-Che Lee
  • Publication number: 20080164449
    Abstract: A passive energy absorbing strut for dynamic restraint includes a hydraulic cylinder, a hydraulic piston rod extending from the cylinder, a rod stem on the end of the rod and having a flange and a stop at opposite ends, a floating piston member sleeved on the stem between the flange and the stop, the piston member having fluid passages therethrough, and a piston spring urging the piston member away from the flange. The flange is sized to restrict the piston passages when the piston member engages the flange. The piston member is driven toward the flange in reaction to initiation of sudden extension of the strut, thereby restricting the piston passages and the flow of hydraulic fluid therethrough. The strut is connected between a piston and cylinder of a pneumatic vehicle end lift to damp sudden extension of the lift in response to loss of the load.
    Type: Application
    Filed: January 8, 2008
    Publication date: July 10, 2008
    Inventors: Joseph L. Gray, Ralph S. McKee
  • Patent number: 7111711
    Abstract: Vibration damper, containing a damping medium-filled cylinder, in which a piston rod with a piston is installed with freedom of axial movement, where, as a function of the stroke of the piston, a bypass connects a working space on the piston rod side to a working space on the side away from the piston rod, the two spaces being separated from each other by the piston, where the piston has at least one through-channel for at least one flow direction, the outlet side this channel being at least partially covered by at least one valve disk, so that a surface is present on the valve disk upon which pressure can act in the opening direction of the disk, where, in addition to the said pressure-actuated surface, the valve disk also has a second pressure-actuated surface, which is separated from the first when the valve disk is closed and which can be put into action by the bypass, so that the effects of the two pressure-actuated surfaces are added to each other.
    Type: Grant
    Filed: February 17, 2004
    Date of Patent: September 26, 2006
    Assignee: ZF Sachs AG
    Inventor: Manfred Grundei
  • Patent number: 7104369
    Abstract: A piston rod with a piston is installed with freedom of axial movement in a damping medium-filled cylinder, where, as a function of the stroke position of the piston, a bypass connects the two working spaces separated from each other by the piston. The piston has at least one through-channel for at least one flow direction, which channel is at least partially covered on the outlet side by at least one valve disk, so that a first pressure-actuated surface to which pressure can be applied in the opening direction is present on the valve disk. In addition to the first pressure-actuated surface, the valve disk has a second pressure-actuated surface, which is separated from the first when the valve disk is closed and which can be actuated via the bypass, in which case the effects of the two pressure-actuated surfaces are additive.
    Type: Grant
    Filed: September 22, 2004
    Date of Patent: September 12, 2006
    Assignee: ZF Friedrichshafen AG
    Inventors: Steffen Heyn, Frank Gundermann, Christian Böhm, Bernd Zeissner, Manfred Grundei
  • Patent number: 6739609
    Abstract: The production of sharp shocks is prevented by increasing resilient gas characteristics in response to the compression stroke acting on a front fork. The front fork comprises a tube 1 connected to the vehicle body and a tube 2 connected to the vehicle wheels and engaging to slide freely with respect to the tube 1. A damper 3 and a suspension spring 7 which is biased in a direction in which the tubes 1, 2 are extended are provided in an interior space between the vehicle-body tube 1 and the vehicle-wheels tube 2. A first gas chamber 4 and an oil chamber 5 into which oil is introduced from the damper 3 are formed in the interior space. A second gas chamber 9 is provided which is connected to the first gas chamber 4 through a orifice 10. A space A which is provided between the outer periphery of the suspension spring 7 and the inner periphery of the vehicle-body tube 1 and is closed by entry of the tip 2a of the vehicle-wheel tube 2.
    Type: Grant
    Filed: June 24, 2002
    Date of Patent: May 25, 2004
    Assignee: Kayaba Industry Co., Ltd.
    Inventor: Tetsuya Miyabe
  • Patent number: 6568664
    Abstract: A flow restriction part (10) which provides a resistance to high speed oil is provided in a reservoir (R), and an air chamber (A2) which contracts according to an oil pressure is disposed underneath this flow restriction part (10). Providing such flow restriction part and air chamber in addition to an air chamber (A1), a repulsive force when the front fork contracts at high speed, such as during sudden braking, increases larger than during normal contraction while mechanical vibration caused by road unevenness during normal running is absorbed.
    Type: Grant
    Filed: October 10, 2001
    Date of Patent: May 27, 2003
    Assignee: Kayaba Kogyo Kabushiki Kaisha
    Inventor: Ken Furuya
  • Patent number: 6446771
    Abstract: A shock absorber is made with a bleed function and preferably a non-return valve function associated with the bleed function. The shock absorber has a cylinder (3) and, working in the latter in working medium and arranged on a piston rod (4), a piston arrangement. The latter comprises at least two first and second pistons (5, 6) arranged at a distance from one another on the piston rod. At least one piston (5) can, in connection with an end position, be introduced into a first space so as, depending on its position in or at the space, to bring about a modified or varied damping force relative to when the piston is located outside the space. The piston rod (4) is provided with an inner second space (15) which is arranged so as to contain said bleed and/or non-return valve function. Additionally or alternatively, the piston (6) working outside the first space is provided with a member performing a bleed function and with any associated non-return valve function.
    Type: Grant
    Filed: November 10, 1999
    Date of Patent: September 10, 2002
    Assignee: Öhlins Racing AB
    Inventors: Torkel Sintorn, Oskar Löfgren
  • Patent number: 6442796
    Abstract: An air damper consists of a tubular cylinder with opposite ends, a piston movable in the cylinder, a first coil spring for resiliently biasing the piston in the direction of one end of the cylinder, a string for transferring dampening effect produced by a motion of the piston to an openable object, a shaft with a flange slidably fitted into the piston and a second coil spring interposed between the flange of the shaft and the piston inside the first coil spring. The second coil spring exerts a resilient biasing force at later stages of the motion of the piston in the direction of the other end of the tubular cylinder.
    Type: Grant
    Filed: January 5, 2001
    Date of Patent: September 3, 2002
    Assignee: Piolax, Inc.
    Inventors: Oomi Arisaka, Seiji Takasugi, Masato Suzuki
  • Publication number: 20020104723
    Abstract: Hydraulic tension stop for vibration dampers, shock absorbers, or similar piston-cylinder assemblies, where each assembly has a fluid-filled working space, the boundaries of which are formed axially by a piston rod guide and the piston and radially by the cylinder and the piston rod which carries the piston, part of this working space also belonging to the tension stop. A stop ring is mounted on the piston rod, which ring cooperates with a slotted, outwardly tensioned damping ring, so that the tension damping can be varied as a function of the stroke. When the stop ring reaches a predetermined position, the damping ring seats in a rest-position channel in a slide face permanently attached to the cylinder, the channel having a conical surface.
    Type: Application
    Filed: February 4, 2002
    Publication date: August 8, 2002
    Applicant: ZF Sachs AG
    Inventor: Steffen Obst
  • Patent number: 6269919
    Abstract: The damper includes a cylindrical housing with a cylindrical passageway formed therewithin. A piston traverses the cylindrical passageway. A strand element is integrally molded with the piston on a first end and integrally molded with an attachment element on a second end. The portion of the cylindrical passageway through which the piston traverses when the damper is in its retracted position has a reduced diameter.
    Type: Grant
    Filed: June 8, 1999
    Date of Patent: August 7, 2001
    Assignee: Illinois Tool Works Inc.
    Inventors: Steven L. Bivens, Eric Parker
  • Patent number: 6189662
    Abstract: The damper includes a cylindrical housing with a cylindrical passageway formed therewithin. A piston traverses the cylindrical passageway. A monofilament element is integral with the piston on a first end and includes a plurality of molded annular rings on a second end. The molded annular rings serve as a male element for engaging a female clamping element with internal serrations. This allows for the female clamping element to be positioned along an adjustable distance with respect to the male element. The portion of the cylindrical passageway through which the piston traverses when the damper is in its retracted position has a reduced diameter.
    Type: Grant
    Filed: September 14, 1998
    Date of Patent: February 20, 2001
    Assignee: Illinois Tool Works Inc.
    Inventors: Steven L. Bivens, Eric Parker
  • Patent number: 5971117
    Abstract: A piston-cylinder aggregate comprising a cylinder in which an axially movable piston rod is arranged is provided. The piston rod has two pistons, which are separated from each other and which produce a damping force of a variable magnitude depending on the piston rod's stroke position. The piston-cylinder aggregate has a bypass area defined in its inner wall along a portion of the length of the cylinder, so that the damping force is at least reduced in the stroke area of the bypass, and the two pistons have a separation equal to or less than the length of the bypass, such that depending on the position of the piston rod, a damping force of variable magnitude is produced. For example, when both pistons are disposed within a section of the cylinder defined by the bypass area, the dampening force exerted by the piston rod is minimized, while when both pistons are outside the bypass area, the dampening force in both stroke directions is maximized.
    Type: Grant
    Filed: May 6, 1997
    Date of Patent: October 26, 1999
    Assignee: Fichtel & Sachs AG
    Inventors: Manfred Grundei, Hans Reimer, Harald Holzapfel
  • Patent number: 5884734
    Abstract: An air damper includes: a piston adapted to reciprocate in a cylinder; an annular recessed portion formed along an outer periphery of the piston; a sealing member fitted in the recessed portion in a slidable manner, adapted to slidingly contact an inner peripheral surface of the cylinder, and forming air chambers on both sides of the piston, respectively, together with the piston; a communicating device allowing the air chambers formed on both sides of the piston to communicate with each other or not to communicate with each other depending on a stopping position of the sealing member; and a reduced-diameter portion formed by reducing a diameter of the cylinder on one end side thereof so as to gradually increase a frictional force between an inner periphery of the reduced-diameter portion and the sealing member.
    Type: Grant
    Filed: May 23, 1997
    Date of Patent: March 23, 1999
    Assignee: Nifco Inc.
    Inventors: Kouji Hiramoto, Takashi Yao, Koji Toida
  • Patent number: 5799759
    Abstract: A positioning element to position two objects which are movable in relation to one another includes a cylinder in which there is an axially movable piston rod with a piston. The piston sealingly divides the cylinder into two working chambers by a piston ring, each of the working chambers containing blocking medium. The sealing by the piston ring can be bypassed during an insertion stroke of the piston rod. The piston includes a piston base body and a valve element, the valve element being movable along the base body to open and close a flow connection between the working chambers. An external opening force can displace the valve element to open the flow connection and permit an automatic extension stroke of the piston rod. The valve element remains open during the extension stroke on account of the flow of blocking medium through the flow connection. The valve element can be displaced to close the flow connection in response to stopping the extension stroke of the piston rod to position the two objects.
    Type: Grant
    Filed: March 7, 1997
    Date of Patent: September 1, 1998
    Assignee: Stabilus GmbH
    Inventor: Klaus Koch
  • Patent number: 5769190
    Abstract: A shock absorber utilizes an array of restrictive rebound fluid flow passages radially formed in a piston assembly. The flow passages are defined by a relatively narrow entrance and a relatively wide exit. A contoured wall form one wall of the passage. The restrictive rebound fluid flow passages restrict the flow-through of rebound fluid. The damping characteristics of the shock absorber are determined by the restriction caused by the general shape of the passages. Because restriction produced by the passages is a function of the contour of the passages and the entrance and exit widths, virtually any damping curve may be achieved by forming a passage having a selected contour.
    Type: Grant
    Filed: January 16, 1996
    Date of Patent: June 23, 1998
    Assignee: Tenneco Automotive Inc.
    Inventor: Stefan Deferme
  • Patent number: 5702091
    Abstract: A gas spring for the hatchback or other closure member of a motor vehicle body automatically stops at an intermediate position between the fully closed and fully opened positions. A piston carrying a piston rod separates the interior of a cylindrical body into first and second chambers. Gas under pressure forces the piston and piston rod towards the extended position to open the closure member, a restricted gas path through a groove in the cylinder wall allowing gas to flow from the second chamber to the first chamber. A third chamber is also defined within the cylinder and has an uninterrupted wall portion and a wall portion incorporating a groove. The third chamber is on the opposite side of the second chamber to the first chamber and has a smaller diameter than the first and second chambers.
    Type: Grant
    Filed: July 11, 1996
    Date of Patent: December 30, 1997
    Assignee: Draftex Industries Limited
    Inventors: Etienne Perrin, Dominique Dony
  • Patent number: 5577579
    Abstract: A suspension damper and a method of manufacturing a suspension damper so that a common cylinder end assembly is used with dampers having cylinder tubes of varying diameters to accommodate piston assemblies having various desirable performance characteristics resulting from the specific diameter thereof. This provides a way of varying the cylinder tube to suit the specifically selected piston assembly while reducing component part proliferation of the complicated cylinder end assembly part of the damper.
    Type: Grant
    Filed: October 30, 1995
    Date of Patent: November 26, 1996
    Assignee: General Motors Corporation
    Inventor: Randall L. Derr
  • Patent number: 5409087
    Abstract: A hydraulic dashpot for motor vehicles. It has a cylinder that accommodates a fluid. A shock-absorbing piston travels back and forth in the cylinder and divides it into two displacement chambers. The piston is connected to a rod that extends through a centering component at one end of the cylinder. A hydraulic decompression-stroke limiter consists of a cup-shaped recess below the rod-centering component and of another piston on the piston rod above the shock-absorbing piston. Channels extend through the stroke-limiting piston and are blocked off in the decompression-stroke direction. The object is a less expensive dashpot. The stroke-limiting piston consists of a thin stroke-limiting disk with a diameter slightly shorter than the critical diameter of the recess and resting on a thicker support.
    Type: Grant
    Filed: June 3, 1994
    Date of Patent: April 25, 1995
    Assignee: August Bilstein GmbH & Co. KG
    Inventors: Rolf Angermann, Reinhard Holscher, Volker Hansemann, Berthold Kolz, Walter Theobald, Friedrich Wiegand
  • Patent number: 5325943
    Abstract: A variable orifice damper includes a sealed cylinder, a piston rod mounted for sliding movement along the axis of the cylinder carrying a piston head and a tail rod, the piston rod and tail rod extending from the interior of the cylinder outward beyond a corresponding support surface on the cylinder wall. The cylinder contains a cavity portion whose internal size varies along the cylinder axis located axially between two adjacent cavity portions of larger size than the intermediate cavity portion. The piston head has a surface whose cross sectional area varies along the axis of the cylinder and is adapted to pass through the cavity portion of variable size, the piston head and cavity portion defining a orifice of variable size therebetween. The piston rod has a bore containing a separator piston actuated by fluid passing the orifice and adapted to compress gas held in the bore.
    Type: Grant
    Filed: June 17, 1992
    Date of Patent: July 5, 1994
    Assignee: The Boeing Company
    Inventor: Harry C. Ralph
  • Patent number: 5217212
    Abstract: A shock absorber having a tubular body member provided with an accumulator chamber in one end thereof, and an axially aligned piston chamber in the other end thereof. A combination piston and piston rod member is telescopically mounted in the piston chamber. A check valve assembly is mounted in the tubular body member, which permits a metered flow of shock absorber oil from the piston chamber into the accumulator chamber when the combination piston and piston rod member is moved in an inward direction in the tubular body member, and which allows a free flow of the oil from the accumulator chamber when the combination piston and piston rod member is moved in an outward direction in the tubular body member.
    Type: Grant
    Filed: March 26, 1992
    Date of Patent: June 8, 1993
    Assignee: Ace Controls, Inc.
    Inventors: William J. Chorkey, Sr., David R. Claydon
  • Patent number: 5095581
    Abstract: A mechanism is provided for maintaining an open door in a selected fixed position includes a hydraulic cylinder having first and second ends. One end of a shaft axially disposed in the cylinder, passes through a hydraulic seal at one end of the cylinder. A piston is axially disposed on the shaft near its other end, and includes o-rings for sealing it against the cylinder walls. The piston includes first and second axially-disposed bores. First and second discs, each including an aperture are axially mounted on the shaft in contact with the opposing faces of the piston and are positioned such that the aperture of each is substantially aligned with one of the bores and blocks the other bore. The discs are held against the faces of the piston with a predetermined amount of force.
    Type: Grant
    Filed: June 12, 1991
    Date of Patent: March 17, 1992
    Assignee: J. Sarto Co.
    Inventor: Julius A. Sarto
  • Patent number: 4964625
    Abstract: A hydraulic damper has an oil lock mechanism for preventing bottoming when the hydraulic damper is fully compressed. The hydraulic damper also includes an outer tube, an inner tube, a cylinder movable with the inner tube, a piston rod movable with the outer tube, a piston fixed to a distal end of the piston rod, and a coil spring disposed in the inner tube. The oil lock mechanism comprises an oil lock piece mounted on an upper end of the cylinder, and an oil lock tube disposed concentrically between the cylinder and the inner tube and having a larger-diameter portion which can be spaced from the oil lock piece when the hydraulic damper is extended and a smaller-diameter portion which can be held in sliding contact with the oil lock piece when the hydraulic damper is compressed.
    Type: Grant
    Filed: July 12, 1988
    Date of Patent: October 23, 1990
    Assignee: Kabushiki Kaisha Showa Seisakusho
    Inventor: Sadao Kawamura
  • Patent number: 4901828
    Abstract: A shock absorber for damping the movement of the body of an automobile is provided. The shock absorber comprises a pressure cylinder forming a working chamber operable to store damping fluid. The shock absorber further comprises a reciprocating piston disposed in the working chamber operable to divide the working chamber into first and second portions. An axially extending piston rod is disposed within the working chamber and is connected to the piston. Finally, the shock absorber includes an annular collar and a split ring for controlling the displacement of the piston.
    Type: Grant
    Filed: May 31, 1989
    Date of Patent: February 20, 1990
    Assignee: Monroe Auto Equipment Company
    Inventors: Robert J. Schmidt, Jerome J. Zawada, Jr.
  • Patent number: 4846317
    Abstract: An apparatus for damping relative movement of parts. The apparatus includes a cylinder defining a fluid chamber. A piston is located in the fluid chamber and divides the fluid chamber into first and second fluid chamber portions. The piston is connected to one of the parts and the cylinder is connected to the other of the parts. The piston and cylinder move relatively in compression and expansion strokes to damp relative movement of the parts. A fluid reservoir is in fluid communication with the first fluid chamber portion. A first valve controls fluid flow from the first fluid chamber portion into the fluid reservoir upon movement of the piston and cylinder during a compression stroke. A damping control provides a variable damping force resisting movement of the piston and cylinder during an expansion stroke. The damping control includes a second valve movable with the piston for controlling the fluid flow from the second fluid chamber portion to the first fluid chamber portion.
    Type: Grant
    Filed: August 25, 1987
    Date of Patent: July 11, 1989
    Assignee: TRW Inc.
    Inventor: Bernard C. Hudgens
  • Patent number: 4821851
    Abstract: Suspension damper with double drum variable valving within the confines of the piston which strokes within the damper that is rotatable to predetermined stations in one revolution to provide a wide range of jounce and rebound damping characteristics and rotatable in an opposite direction from any station for maximized valve restriction producing optimized vehicle lift and dive control.
    Type: Grant
    Filed: August 21, 1987
    Date of Patent: April 18, 1989
    Assignee: General Motors Corporation
    Inventors: William C. Kruckemeier, Gustavus P. Bock, Wayne V. Fannin
  • Patent number: 4819770
    Abstract: A hydraulic device is provided for controlling the rate of relative movement of first and second members between predetermined first and second stations. The device includes a housing connected to the first member and provided with a first cavity for hydraulic fluid and a second cavity for hydraulic fluid segregated from the first cavity. The first cavity has adjacent first and second segments with the second segment having a greater cross-sectional area. An orifice is disposed adjacent an end portion of the first cavity first segment which is remote from the second segment and interconnects the cavities. A valve is remote from the orifice and permits restricted hydraulic fluid flow from the first cavity to the second cavity and substantially unrestricted hydraulic flow from the second cavity to the first cavity. The direction of flow through the valve depends upon the direction of movement of a piston mounted for reciprocatory movement within the first cavity.
    Type: Grant
    Filed: October 13, 1987
    Date of Patent: April 11, 1989
    Assignee: Rite-Hite Corporation
    Inventor: Norbert Hahn
  • Patent number: 4797971
    Abstract: A control mechanism for a door of a motor vehicle is described that is actuated via an inside and outside handle and comprises a piston-cylinder unit arranged between a door post and the vehicle door. It has a piston provided with passage openings for a pressure medium, the piston interacting with an interior valve that separates two working chambers of the cylinder from one another. The control mechanism is equipped with a blocking valve controlling the medium flow, this blocking valve being arranged in a control circuit connecting the two working chambers of the cylinder, acting against the flow direction. This blocking valve, via a control element at a door handle, can be controlled in such a way that the door is blocked in at least one intermediate position. The cylinder has at least one overflow duct between the two working chambers, the flow-through of which is controlled by the piston of the unit. The duct extends over an area into which the piston dips, up to a door opening angle of about 30.degree.
    Type: Grant
    Filed: January 27, 1987
    Date of Patent: January 17, 1989
    Assignee: Dr. Ing. h.c.F. Porsche Aktiengesellschaft
    Inventors: Georg Eger, Rainer Srock