Position Of Thrust Member Relative To Chamber Patents (Class 188/284)
  • Patent number: 6516257
    Abstract: The invention provides a method for independent axle control of a variable force damper system by providing at least one axle velocity signal from at least one vehicle sensor. The method then applies an axle control algorithm to the at least one axle velocity signal, thus determining at least one axle damping command as a function of the axle control algorithm.
    Type: Grant
    Filed: January 3, 2001
    Date of Patent: February 4, 2003
    Assignee: Delphi Technologies, Inc.
    Inventors: David A. Shal, Timothy J. Juuhl, Michael R. Lukuc
  • Patent number: 6467592
    Abstract: The hydraulic cylinder or shock absorber arrangement has a cylinder unit limiting an inner space in which a medium in the form of a gas or a liquid is intended to be placed. A forwardly and backwardly movable piston unit is placed such that it can slide within the space that is defined by the piston into a first chamber and a second chamber. An inlet/outlet is defined in the respective chambers of the cylinder unit for the addition to and removal of medium from the chambers together with devices which co-act in order to determine the relative position of the piston within the cylinder unit, an active first part of which is attached to the cylinder unit and arranged stretching into a recess that is arranged in the piston unit.
    Type: Grant
    Filed: March 26, 2001
    Date of Patent: October 22, 2002
    Inventor: Lars Dernebo
  • Patent number: 6454061
    Abstract: A powerful high frequency shock absorber/accelerator uses compressed air but maintains a substantially uniform level of force throughout retraction and extension strokes. A piston moving in an inner chamber compresses gas in the chamber. Initially, an aperture allows compressed gas to be pushed to an outer storage chamber surrounding the inner chamber. As the piston moves further, sealing structure seals gas coming through the aperture thereby isolating the compressed air in the outer chamber from the inner chamber. At the end of the retraction stroke the small amount of remaining air is vented to outside and the piston faces a small counterforce-generating member. When the extension stroke is initiated the counterforce-generating member moves the piston a small distance until the seal is broken. The force of the compressed air rushing back into the inner chamber drives the extension stroke. Additional embodiments include replacing outer chamber with external source of gas.
    Type: Grant
    Filed: October 17, 2001
    Date of Patent: September 24, 2002
    Inventor: Yevgeny Antonovsky
  • Patent number: 6443271
    Abstract: A shock absorber includes a housing, a piston slidable in the housing, a piston rod extending outwardly from the piston, a cup-shaped stop cap secured to the free end of the piston rod, and an adjusting ring which protrudes from the end of the housing and can be rotated to adjust the damping coefficient by adjusting the open cross-section of throttle openings through which a hydraulic fluid is displaced by the piston. When a load pushes against the stop cap, the maximum travel is limited by the stop cap bearing directly against a rigid end ring of the housing. The load forces are introduced directly from the stop cap into the housing, without applying any loads onto the adjusting ring or other components. The adjusting ring and a return spring coaxially on the piston rod are accommodated within the stop cap in the fully retracted position.
    Type: Grant
    Filed: June 13, 2001
    Date of Patent: September 3, 2002
    Assignee: Weforma GmbH
    Inventor: Armin Schmidt
  • 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
  • Publication number: 20020100649
    Abstract: A vehicle suspension damper configured to be arranged between a wheel assembly and a body of a vehicle is provided that includes a cylindrical reservoir tube with a piston mounted for reciprocating movement within the reservoir tube. A piston rod is connected to the piston and extending axially therefrom and through one end of the reservoir tube. An annular rod guide assembly surrounds the piston rod and includes a magnetic portion. A non-magnetic dust tube is disposed around the reservoir tube, the dust tube being operatively connected to the piston rod. A generally longitudinal sensor housing is formed in the dust tube adjacent the magnetic portion and a linear sensor is disposed in the sensor housing adapted to detect the position of the magnetic portion.
    Type: Application
    Filed: January 30, 2001
    Publication date: August 1, 2002
    Applicant: DELPHI AUTOMOTIVE SYSTEMS
    Inventors: Demetris A. Agrotis, Bradley S. Farrenkopf, Kari A. Roth, George A. Spaeth
  • Patent number: 6412615
    Abstract: A hydraulic shock absorber for motor vehicles produces additional damping, starting at a certain immersion depth of the piston rod. This takes place by an auxiliary cylinder positioned axially inside the cylinder which, when the piston rod is immersed, is closed by an auxiliary piston that moves at the same time. The associated pressure increase inside the hydraulic shock absorber causes a correspondingly designed valve to open inside the auxiliary cylinder. The fluid exchange that causes damping takes place between two working chambers of the cylinder through a connection of the two working chambers that runs through the auxiliary piston and reduces their opening cross section to the working chamber associated with the auxiliary piston by pushing the auxiliary piston into the auxiliary cylinder.
    Type: Grant
    Filed: September 15, 2000
    Date of Patent: July 2, 2002
    Assignee: Bayerische Motoren Werke AG
    Inventor: Laszlo Perez
  • Publication number: 20020011387
    Abstract: A shock-absorbing device includes an airtight cylindrical casing; at least one compressible springy ball arranged in the cylindrical casing; a main piston mounted in the cylindrical casing above the at least one compressible springy ball and reciprocated to compress the at least one compressible springy ball, the main piston having a piston rod extended out of the cylindrical casing; a damping substance flowing in the cylindrical casing; and a plurality of main piston valves respectively installed in said main piston for enabling the damping substance to flow between an upper chamber in the cylindrical casing above the main piston and a lower chamber in the cylindrical casing below the main piston.
    Type: Application
    Filed: March 20, 2001
    Publication date: January 31, 2002
    Inventor: Yu-Hsueh Chu
  • Patent number: 6318524
    Abstract: A piston-cylinder unit includes a cylinder with a piston rod guide and a piston rod with a piston axially movably mounted in the cylinder so that the piston rod runs through a hole in the piston rod guide. A movement determination device comprising a transmitter portion and a receiver portion determine the movement of the piston from the travel time of waves generated by the transmitter portion. The movement determination device is arranged inside the piston rod guide, and waves reflected by the piston-piston rod component group are analyzed to determine the movement of this component group.
    Type: Grant
    Filed: January 14, 1999
    Date of Patent: November 20, 2001
    Assignee: Mannesmann Sachs AG
    Inventors: Dieter Lutz, Achim Thomä
  • Patent number: 6305673
    Abstract: A vibration control system utilizes a liquid spring filled with a compressible liquid. In its most general embodiment, the vibration control system minimizes the transmission of vibration between a first mass and a second mass, i.e. vehicle frame/vehicle cabin, structure/ground, machinery/platform. The liquid spring can be either a passive or an active system. An active system utilizes a second volume of compressible fluid. A passive system only uses a single volume of fluid. Further, the liquid spring can provide either spring force or both spring and damping forces. Alternatively, a single volume liquid spring can be utilized in conjunction with a conventional damper.
    Type: Grant
    Filed: June 29, 2000
    Date of Patent: October 23, 2001
    Assignee: Liquidspring Technologies, Inc.
    Inventors: Damon Delorenzis, Richard J. Meyer
  • Publication number: 20010025753
    Abstract: A vibration damper includes a rebound, in particular a rebound spring. The vibration damper includes a piston which is formed on an axially movable piston rod and which separates two working chambers in a cylinder, the working chamber penetrated by the piston rod being closed off with a lid and containing the rebound. An out-stroke of the piston rod relative to the cylinder includes an idle-stroke which starts at a minimum out-stroke and in which the rebound does not counteract the piston rod movement, a working-stroke which ends at a maximum out-stroke and in which the rebound counteracts the piston rod movement, and a point of application at which the idle-stroke ends and the working-stroke begins. The vibration damper further includes an arrangement configured to adjust the point of application.
    Type: Application
    Filed: April 2, 2001
    Publication date: October 4, 2001
    Inventors: Wolfgang Pfundstein, Ralph Samietz, Reiner Scheu
  • Patent number: 6250612
    Abstract: A ram (10) with a hydraulic cylinder (22) and piston (52) has an electronics enclosure compartment (54) integrated within it at one end. The compartment (54) is formed by two clam shells (70, 72) which are bolted to the end of the cylinder (22) so as to create a chamber for housing the electronics (66). The outer clam shell (72) has an axially aligned ram mounting attachment (74) integrally formed on it, and the inner clam shell (70) has an axial opening to which is sealed a hollow tube (56) which extends axially within the ram (10) so as to enclose a sensor (60) which is associated with the electronics (66) in the compartment (54).
    Type: Grant
    Filed: March 2, 1999
    Date of Patent: June 26, 2001
    Assignee: Actuant Corporation
    Inventor: Robert A. Doll
  • Patent number: 6213261
    Abstract: A hydropneumatic spring, which is preferably articulately arranged between a vehicle body and a wheel guiding part in motor vehicles, has a fluid-filled cylinder which is entered by an outwardly sealed piston rod having a piston connected at the internal end. For altering spring force-deflection progressivity characteristic, a first working chamber of the cylinder is in constant hydraulic connection with a first spring energy store device and a second working chamber of the cylinder is in constant hydraulic connection with a second spring energy store device via a second valve device via a first valve device. In a mid spring deflection range, a second spring energy store device is connected via a second valve device and a bypass to the first spring energy store device. The bypass includes an axially extending channel arranged between the first working chamber and the second working chamber.
    Type: Grant
    Filed: January 14, 1998
    Date of Patent: April 10, 2001
    Assignee: Mannesmann Sachs AG
    Inventor: Ernst-Achim Kunkel
  • Patent number: 6199708
    Abstract: A railcar cushioning device with a gas charged cylinder and a piston contained in the cylinder for cushioning buff and draft impacts. An elastomer spring is contained in the cylinder between the piston and an end of the cylinder to locate the piston in a neutral position.
    Type: Grant
    Filed: March 5, 1999
    Date of Patent: March 13, 2001
    Assignee: ASF-Keystone, Inc.
    Inventor: Jay P. Monaco
  • 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: 5667041
    Abstract: A rebound cutoff feature is provided for a strut-type suspension damper which includes a hydraulic stop feature in combination with a mechanical stop to limit rebound travel. The strut's piston rod carries a valve collar which interacts with the sole flow passage between the compression and rebound chambers of the strut to hydraulically decelerate movement as the rebound travel limit of the strut is approached.
    Type: Grant
    Filed: November 3, 1995
    Date of Patent: September 16, 1997
    Assignee: General Motors Corporation
    Inventor: Eric Lee Jensen
  • Patent number: 5664286
    Abstract: A hinge mechanism has a damping mechanism and is capable of removing or reducing to the least extent the damping action of the damping mechanism when opening the seat or the seat lid of a toilet bowl, of securely holding the seat or the seat lid at the open position, of making the damping action effective so that the seat or the seat lid can turn gradually to its closed position and of avoiding the breakage of the damping mechanism due to jerky loading when the seat or the seat lid is turned with a jerk. The hinge mechanism comprises a case, a hinge shaft supporting the seat or the seat lid and supported in the case for rotation and axial movement, a fluidic damping mechanism formed between the case and the hinge shaft, and a resilient means biasing the hinge shaft in one direction.
    Type: Grant
    Filed: August 15, 1995
    Date of Patent: September 9, 1997
    Assignee: Katoh Electrical Machinery Co., Ltd.
    Inventor: Akira Sorimachi
  • Patent number: 5595270
    Abstract: Vibration damper, in particular a single-tube vibration damper, comprising a cylinder which is closed on the end by a piston rod guide which centers an axially movable piston rod with a piston, whereby the piston with its damping valves divides the cylinder into an upper and a lower work chamber, and a decompression stop in the form of a compression spring with a round wire cross section which is located in the upper working chamber, characterized by the fact that the compression spring is designed in multiple stages, whereby a first longitudinal segment of the spring interferes with the cylinder and is held in the cylinder by means of this interference fit, and an additional longitudinal segment forms a guide with respect to the piston rod.
    Type: Grant
    Filed: June 8, 1995
    Date of Patent: January 21, 1997
    Assignee: Fichtel & Sachs AG
    Inventors: Gunther Braun, Sabine Rucks
  • Patent number: 5535862
    Abstract: A suspension strut comprising a tube substantially closed at both ends and containing fluid; a piston assembly slidably mounted in the tube and making a sealing fit therewith, the piston assembly separating a compression chamber and a rebound chamber within the tube; a piston rod attached to the piston assembly and extending through the rebound chamber and out of one end of the tube; and a rebound stop mounted on the piston rod between the piston assembly and said one end of the tube, the rebound stop comprising a substantially rigid metallic ring secured to the piston rod and an annular bumper compressible between the metallic ring and the said one end of the tube during a rebound stroke, wherein the rebound stop and/or the one end of the tube is such as to alter the normal compression characteristics of the bumper on initial contact and compression of the bumper.
    Type: Grant
    Filed: January 18, 1995
    Date of Patent: July 16, 1996
    Assignee: ACG Deutschland GmbH
    Inventors: Erwin Jentsch, Hartmut Wollstadter
  • Patent number: 5509512
    Abstract: A vehicle, including a vehicle body, a chassis with wheels and tires on which the vehicle rests, a number of vehicle suspension springs and shock absorbers which are mounted between the wheels and the vehicle body and execute a change in their axial length as a function of the wheel spring travel in the form of a displacement between a piston fastened to a piston rod and a pressure tube of the shock absorber, and thereby displace a damping medium through a damping device, as well as an arrangement to fasten the piston rod and the pressure tube to the vehicle body and the wheel, characterized by the fact that the shock absorber has a damping force family of characteristics which consists of at least three individual damping force families of characteristics, the first damping force family of characteristics of which is designed so that it exerts a very low damping force, whereby this damping force family of characteristics is located in the vicinity of the normal spring deflection range of the shock absorber,
    Type: Grant
    Filed: February 17, 1994
    Date of Patent: April 23, 1996
    Assignee: Fichtel & Sachs AG
    Inventor: Manfred Grundei
  • 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: 5398786
    Abstract: According to an illustrative example of the invention a fluid damper comprises a cylinder and a piston rod axially movable through one axial end of the cylinder. The piston rod is provided with two damping pistons within a cavity inside the cylinder. The two pistons are axially spaced and in sealing engagement with an internal circumferential face of the cylinder. In a middle section of the cylinder there is provided a by-pass by an axial groove in the inner circumferential wall of the cylinder. In each axial position of the piston rod at least one piston is within the axial extent of the by-pass. When one of the pistons moves beyond the axial extent of the by-pass toward an axial cylinder end nearer to this piston, a throttled channel through this piston allows restricted fluid flow through the piston. When this piston moves in the other direction away from the nearer end of the cylinder, liquid can flow through this piston without substantial flow resistance.
    Type: Grant
    Filed: April 6, 1993
    Date of Patent: March 21, 1995
    Assignee: Stabilus GmbH
    Inventor: Rolf Mintgen
  • Patent number: 5368141
    Abstract: A displacement sensitive valve mechanism incorporated in a shock absorber for a motor vehicle suspension which provides substantially unrestricted hydraulic flow between a first rebound chamber and a second rebound chamber through a first range of displacement of a piston rod and progressively restricts the hydraulic flow between the first rebound chamber and the second rebound chamber during a second range of displacement of the piston, thereby progressively increasing the dampening force resisting displacement of the piston in the second range of displacement.
    Type: Grant
    Filed: December 27, 1993
    Date of Patent: November 29, 1994
    Assignee: Ford Motor Company
    Inventor: William H. Clarke
  • Patent number: 5333708
    Abstract: A twin-tube hydraulic damper includes a fluid-filled cylinder tube closed at its lower end by a cylinder end. A piston is slidably mounted in the cylinder tube and divides an interior volume of the cylinder tube into upper and lower chambers. A plurality of intake slots permit fluid to flow from a reservoir to the lower chamber. A plurality of exit flow openings permit fluid to flow from the lower chamber to the reservoir. A cut-off cap is slidably mounted on the cylinder end and sprung away from the cylinder end by a reaction spring. An annular wall formed on the cylinder end receives the cap as the piston engages an activation spring near the travel limit of a compression stroke. Reduced fluid flow through the exit flow openings increases the damping force to reduce harsh impacts.
    Type: Grant
    Filed: January 11, 1993
    Date of Patent: August 2, 1994
    Assignee: General Motors Corporation
    Inventors: Eric L. Jensen, Rachel J. Belvo, Randall L. Derr
  • Patent number: 5261843
    Abstract: Two embodiments of concentric tilt and trim cylinder arrangements for machine propulsion units for achieving trim and tilt-up operation. Each embodiment includes an arrangement that permits the outboard drive to pop up when an underwater obstacle is struck, but which preclude popping up operation when operating in reverse. In addition, one embodiment incorporates an arrangement for ensuring against inadvertent trim up when trim down is being called for.
    Type: Grant
    Filed: June 24, 1992
    Date of Patent: November 16, 1993
    Assignee: Sanshin Kogyo Kabushiki Kaisha
    Inventors: Eiichiro Tsujii, Yoshiyuki Katsumata
  • Patent number: 5219414
    Abstract: A shock absorber has a spring disc to close one end of a fluid path defined through a piston for generating damping force in response to piston stroke in one of bounding and rebounding direction. A coil spring is also provided for providing additional spring force for flow restriction and thus increasing damping force to be generated in response to the piston stroke in one of the bounding and rebounding directions. The coil spring is so oriented to become active in response to a piston stroke in a magnitude greater than a predetermined value and greater than a piston stroke criteria which defines neutral range of the piston stroke.
    Type: Grant
    Filed: December 23, 1991
    Date of Patent: June 15, 1993
    Assignee: Atsugi Unisia Corporation
    Inventor: Fumiyuki Yamaoka
  • Patent number: 5195914
    Abstract: A shock absorber adapted for use with the swivel bracket assembly of an outboard motor or the like, is disclosed, which swivel bracket assembly permits rotation of the motor to clear an underwater object if and when a boat strikes such an object. The shock absorber has a two stage operation in that it permits a swivel bracket assembly to rotate and provides a counterforce that is initially lower, and after some degree of rotation, preferably sufficient to have the drive shaft housing clear the object, provides a higher counterforce to continued rotation.
    Type: Grant
    Filed: February 25, 1991
    Date of Patent: March 23, 1993
    Assignee: Outboard Marine Corporation
    Inventors: Gregory J. Binversie, David C. Calamia, David J. Hall, H. Norman Petersen
  • Patent number: 5169131
    Abstract: A shock absorber capable of effectively functioning even in case of emergency or abnormality, significantly reducing the manufacturing cost and highly simplifying the structure. A piston is arranged so as to divide a liquid chamber defined in a casing into two liquid chamber sections and a liquid passage is arranged so as to cause the chamber sections to communicate with each other. Also, a movable guide member is provided in the casing and a spring is interposed between the guide member and a flange of an actuation rod, so that the return spring permits both actuation rod and movable guide member to carry out the return operation. Thus, the shock absorber eliminates arrangement of an accumulator in the shock absorber.
    Type: Grant
    Filed: November 18, 1991
    Date of Patent: December 8, 1992
    Assignee: Fuji Seiki Kabushiki Kaisha
    Inventor: Ryota Shimura
  • Patent number: 5160123
    Abstract: A buffer for railway vehicles includes a plunger telescopically received within an outer cylinder. An internal speed control valve, essentially independently of the forces acting on the buffer, causes the buffer to move inwardly at a predetermined initial velocity which is reduced by a uniform deceleration of such a level that the main portion of the plunger stroke is always used. The initial velocity corresponds to the maximum speed allowed during shunting operations, plus a safety margin determined by experience. The buffer has a leakage slot between the plunger and the cylinder to allow fluid flow around a throttling valve when the throttling valve is closed. The area of the leakage slot is dependent on the pressure within the buffer and the position of the plunger relative to the cylinder.
    Type: Grant
    Filed: December 28, 1990
    Date of Patent: November 3, 1992
    Inventor: Sten H. Danieli
  • Patent number: 5131512
    Abstract: In a hydraulic telescopic damper with a cylinder (10) and a piston (12) which has a check valve (O-ring 18) and a narrow opening (22), a valve member (30) is mounted on the side of piston (12) away from the pressure side. Valve member (30) is urged by the force of a spring (36) in a locking position of piston (12) and keeps opening (22) closed. The telescopic damper thereby locks automatically. Exerting an additional manual force on the piston rod can release the self-locking action once more.
    Type: Grant
    Filed: November 6, 1990
    Date of Patent: July 21, 1992
    Assignee: Friedhelm Steinhilber
    Inventors: Friedhelm Steinhilber, Ludwig Bantle, Heinz Frochte
  • Patent number: 5099745
    Abstract: The invention is low-noise, low-pressure torpedo launching system having cially designed ports connecting a water cylinder to an impulse tank and to a method for designing such ports. The invention uses specially designed C-shaped water cylinder discharge ports to provide a continuous and minimized pressure gradient as the ports are closed by the water piston. The resulting controlled deceleration of the water piston reduces operational noise, reduces mechanical stresses and eliminates the need for auxiliary dashpot components.
    Type: Grant
    Filed: July 25, 1990
    Date of Patent: March 31, 1992
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventors: Richard F. Hubbell, George Rosner
  • 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: 5024301
    Abstract: A shock absorber has a rebound stop assembly. The rebound stop assembly is mounted to the piston rod and includes an outer housing assembly slidably disposed within the working cylinder of the shock absorber and an inner housing member secured to the piston rod and slidably disposed in the outer housing member. The housing members define a damping chamber therebetween for receiving damping fluid therein. The rebound stop assembly also includes a damping device associated with the inner and outer housing members for creating a damping force in the shock absorber after a predetermined amount of rebound stroke of the piston within the working cylinder. A restrictive passage controls the flow of fluid from the damping chamber and this restrictive fluid flow provides additional damping at the end of the rebound stroke.
    Type: Grant
    Filed: May 23, 1990
    Date of Patent: June 18, 1991
    Assignee: Ford Motor Company
    Inventor: Robert H. Cook
  • 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: 4915364
    Abstract: A fluid suspension unit, particularly for heavy motor vehicles, comprising an outer cylinder and an inner cylinder slidably mounted within the outer cylinder, the outer and inner cylinders defining therein a chamber of variable volume containing hydraulic fluid and compressed gas. A diaphragm divides the chamber into two portions and has an opening therein which is normally closed by a mushroom valve. The upper portion of the chamber has a constant volume and a prefixed pressure and the lower portion has a variable volume and a variable pressure, lower or at most equal to that of the upper portion. The mushroom valve, normally closed, opens mechanically only when the suspension reaches a predetermined degree of compression that is when the pressure in the two portions of the chamber are the same. The valve is closed by gravity when the suspension returns to the same predetermined degree of compression.
    Type: Grant
    Filed: November 18, 1987
    Date of Patent: April 10, 1990
    Inventor: Roberto Perlini
  • Patent number: 4852703
    Abstract: A shock absorber adapted to be mounted between a body and a wheel shaft in a vehicle such as a car or a motorcycle for reducing shocks and vibrations derived from a road. The shock absorber includes a sub-cylinder mounted in a cylinder at one end thereof, a rebound cushion mounted in the sub-cylinder at one end thereof, and an oil-lock piston mounted on a piston rod of the cylinder in confronting relation to the interior of the sub-cylinder. As the piston approaches the end of the expanding stroke, the oil-lock piston is fitted in the sub-cylinder, at which time oil in the sub-cylinder is compressed and then flows into an oil chamber below the oil-lock piston via an annular gap around a periphery of the oil-lock piston and a small-diameter hole in the oil-lock piston. Due to the flow resistance of the small-diameter hole, an oil-lock load can be obtained.
    Type: Grant
    Filed: July 6, 1988
    Date of Patent: August 1, 1989
    Assignee: Kayaba Kogyo K.K
    Inventor: Yukio Nishimoto
  • Patent number: 4838393
    Abstract: A shock absorber (10) has a rebound stop assembly (22). The rebound stop assembly (22) rests upon a shoulder (30) fixed to a piston rod (16). The rebound stop assembly (22) includes an elastomeric ring (24) interposed between two collars (26 and 28) forming an annular chamber (74) therebetween. At the end of the rebound stroke of piston rod (16), the rebound stop assembly (22) is axially compressed between the shoulder (30) of piston rod (16) and the rod guide (18) until the elastomeric ring (24) deforms to abut the inner wall (64) of the working cylinder. As the elastomeric ring deforms, the annular chamber decreases in volume. A restrictive passage (71) allows a restrictive flow of fluid therefrom. An additional chamber (70) is formed which is in restrictive fluid communication through the passage (71) with section (68) of rebound chamber (20).
    Type: Grant
    Filed: September 20, 1982
    Date of Patent: June 13, 1989
    Assignee: Ford Motor Company
    Inventors: Jack W. Mourray, James P. Nagy
  • 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: 4782925
    Abstract: In a double-tube vibration damper the flow of liquid from the lower working chamber to the reservoir chamber is controlled by a bottom valve. This bottom valve has additionally the function of hydraulic abutment for the piston rod when the piston rod approaches its innermost position. An abutment spring is connected with the inner end of the piston rod. This abutment spring cooperates with a control body being a part of the bottom valve and being urged towards a minimum damping position by a return spring. When the abutment spring abuts against the control body at a predetermined position of inward movement of the piston rod the control body is displaced towards a maximum damping position. The control body cooperates with a flow passage. Various embodiments of the flow passage are proposed in order to vary the characteristics of the bottom valve with respect to its function as hydraulic abutment.
    Type: Grant
    Filed: December 31, 1986
    Date of Patent: November 8, 1988
    Assignee: Fichtel & Sachs AG
    Inventor: Manfred Grundei
  • Patent number: 4778127
    Abstract: A missile (10) and concepts for deploying the fins (14) thereof from a stored to a deployed position are disclosed. One device described has three main portions including: A first end portion (32) housing an initiator (22) that powers the device and a locking mechanism (26) that holds the fin at its stored and its locked position; a central portion (34) housing a driven piston (24) that rotates a positively connected fin (14) from the stored to the deployed position; and, a second end portion (36) housing a damping system that controls the rate of deployment of the fins.
    Type: Grant
    Filed: September 2, 1986
    Date of Patent: October 18, 1988
    Assignee: United Technologies Corporation
    Inventor: Jerome G. Duchesneau
  • Patent number: 4776440
    Abstract: A shock absorber comprises a cylinder with a cylindrical bore, an actuator piston with a rod slidably received in the bore, and an adjustment piston slidably received in the bore and resiliently kept in a predetermined position. The adjustment piston cooperates with the actuator piston to define an adjustment chamber therebetween. The adjustment piston is movable in response to pressure developing within the adjustment chamber to vary a rate of air flow between the adjustment chamber and the ambient atmosphere so as to decelerate the actuator piston during its extending movement relative to the cylinder, thus providing a slow and gradual extending movement of the actuator piston.
    Type: Grant
    Filed: December 3, 1985
    Date of Patent: October 11, 1988
    Assignees: Nissan Motor Co., Ltd., Kato Hatsujo Kaisha Ltd.
    Inventors: Katsumi Yamada, Toshinari Hojima
  • Patent number: 4768629
    Abstract: In a double-tube vibration damper the piston acts on an abutment spring when arriving at a predetermined position during its inward stroke. The abutment spring acts on a control member. The control member cooperates with a bottom passage to reduce the cross-sectional area of the bottom passage in response to the piston starting to act onto the abutment spring such as to reduce the cross-sectional area of the bottom passage. In this way a hydraulic abutment function is obtained on inward movement of the piston rod. The control member is biased by a return spring towards the abutment spring. The abutment spring acts with its end remote from the control member onto a friction ring, which friction ring is frictionally guided by the inner face of the cylinder. The biasing action of the return spring is larger than the force necessary for moving the friction ring along the inner face of the cylinder.
    Type: Grant
    Filed: September 18, 1986
    Date of Patent: September 6, 1988
    Assignee: Fichtel & Sachs AG
    Inventor: Felix Wossner
  • Patent number: 4756512
    Abstract: A shock absorber strut that includes an inner and an outer tube which slide one over the other. The combination of a keeper ring and a series of key stops secures the tubes while allowing independent motion therebetween. An elastomeric material contained within the tubes functions as the shock absorber material and bearing surfaces allow for easy movement between the tubes. A method is also provided for replacement of one of the bearing surfaces without removal of the entire strut from the vehicle even though the elastomeric material is under preload.
    Type: Grant
    Filed: December 15, 1986
    Date of Patent: July 12, 1988
    Assignee: Miner Enterprises, Inc.
    Inventor: Robert S. Toms, Jr.
  • Patent number: 4754955
    Abstract: An improved snubber apparatus for an air cushion within a forming press is provided. A floating piston is mounted within the air cushion and defines a snubbing chamber. As the air cushion returns to its top stroke position after yieldably deforming to cushion a member within the forming press, a movable piston within the air cushion contacts the floating piston, forcing it to move in the direction reducing the volume of the snubbing chamber. A check valve is provided between a cushion chamber and the snubbing chamber which maintains the pressure in the snubbing chamber at a minimum equivalent to the pressure in the cushion chamber. As the volume of the snubbing chamber is reduced, the air trapped within is rapidly compressed to a value snubbing the motion of the air cushion. The snubber valve is provided communicating with the snubbing chamber and maintained in a closed position by the air pressure within the cushion chamber.
    Type: Grant
    Filed: September 28, 1982
    Date of Patent: July 5, 1988
    Assignee: Verson Allsteel Press Company
    Inventors: Tsuruo Otsuka, Edward J. Brzezniak
  • Patent number: 4716930
    Abstract: A pneumatic time delay valve primarily adapted for use in the ejection system of electronic or optical countermeasure devices and the like wherein an explosive squib is employed to create a momentary charge of high pressure gas used to depress the firing pin on the device to activate the device and also to push the device out of an ejection tube. The invention comprises means for splitting the pressurized gas into a first conduit communicating with the firing pin and a second conduit communicating with the device to apply the ejection pressure thereon and a time delay valve disposed within the second conduit for delaying the application of the gas to the device. During the time delay period, a piston is forced down a cylindrical bore forcing metering fluid through an orifice.
    Type: Grant
    Filed: July 18, 1986
    Date of Patent: January 5, 1988
    Assignee: Sanders Associates, Inc.
    Inventors: Martin R. Richmond, Mark A. Hayner
  • Patent number: 4700611
    Abstract: A cushioning mechanism in a pneumatic cylinder utilizing a supplied air pressure, and a method of cushioning a piston in the pneumatic cylinder. Cushioning chambers are provided at opposite ends of a cylinder body of the pneumatic cylinder. Respective differential pressure valves and relief valves are provided between each of the cushioning chambers and an air supply. A cushioning member is disposed between each cushioning chamber and a cylinder bore. Air supplied under pressure from the air supply is stored in one of the cushioning chambers. When the piston is displaced to push the cushioning member, the air in the cushioning chamber is compressed to cushion the piston. As the cushioning member is moved a prescribed interval, the cushioning chamber is vented to atmosphere.
    Type: Grant
    Filed: September 13, 1984
    Date of Patent: October 20, 1987
    Assignee: Shoketsu Kinzoku Kogyo Kabushiki Kaisha
    Inventor: Junya Kaneko
  • Patent number: 4635766
    Abstract: A suspension strut for an automotive vehicle comprises a working cylinder, piston rod, a pressure piston carried within a working cylinder upon the piston rod, a first rod bearing located at one end of the working cylinder and a second piston rod bearing extending telescopically from piston rod and slidably engaged with the working cylinder.
    Type: Grant
    Filed: January 14, 1985
    Date of Patent: January 13, 1987
    Assignee: Ford Motor Company
    Inventor: Thomas R. Street, Jr.
  • Patent number: 4595159
    Abstract: Landing gear mechanism includes a restrictor assembly containing a primary orifice for controlling the rate of instroke of the gear during landing and a taxi instroke bypass valve which provides for increased flow of hydraulic fluid within the gear whenever the gear engages a bump during taxiing to reduce the damping loads that would otherwise occur if all of the hydraulic fluid were required to flow through the primary orifice. The taxi instroke bypass valve assembly includes a bypass passage around the primary orifice, and a slide member which is axially movable relative to the orifice restrictor assembly for opening and closing the bypass passage.
    Type: Grant
    Filed: November 13, 1984
    Date of Patent: June 17, 1986
    Assignee: Pneumo Corporation
    Inventor: Louis C. Hrusch
  • Patent number: 4590818
    Abstract: A speed change gear shift rod with cushioning function which is performed when the speed change gear is being operated is shown. The shift rod is supported in a freely slideable manner in the direction of the shaft, within a blind supporting hole provided inside a main case. An oil containment section is provided at the back of the supporting hole, formed between the end surface of the shaft end section and the back surface of the supporting hole during a speed change operation, when the shaft end section slides to the back of the supporting hole. An oil channel is also provided in the shaft end section or in the supporting hole, making it possible to divert oil from the inside to the outside of the previously mentioned shaft end section.
    Type: Grant
    Filed: April 6, 1984
    Date of Patent: May 27, 1986
    Assignee: Tochigifujisangyo Kabushikigaisha
    Inventor: Masao Teraoka
  • Patent number: 4570912
    Abstract: A pneumatic spring counterbalance extensible link including a closed end cylinder with an end connector, a piston and rod assembly within the cylinder and maintained therein by the crimped over end portion of the cylinder retaining a rod bushing and rod to cylinder seal assembly. The cylinder is pressurized preferably prior to assembly of the bushing and seal assembly into the cylinder. The piston assembly includes an effective check valve and orifice by-pass structure for metered gas flow past the piston in one direction and free flow past the piston in the other direction of piston movement. A small predetermined amount of oil is contained in the cylinder and provides lubrication for the seals and piston and provides a damping effect at the end of the extension stroke. A standpipe sleeve is secured on the piston extending toward the seal assembly around the piston rod and controls disposition of the oil to assure damping at the end of the extension stroke.
    Type: Grant
    Filed: October 8, 1982
    Date of Patent: February 18, 1986
    Assignee: AVM, Inc.
    Inventors: Daniel P. Dodson, George C. Ludwig