Resistance Alters Relative To Direction Of Thrust Member (e.g., High Resistance In One Direction, Low In The Other) Patents (Class 188/281)
  • Patent number: 7740263
    Abstract: A front wheel supporting structure for a motorcycle (1) includes a pair of front forks (10, 20) provided on the right and left sides of a front wheel (2) for supporting the front wheel (2) to a frame (5) of the motorcycle (1). The front forks (10, 20) includes a first front fork (20) which generates a damping force for damping a vibration of the front wheel (2) depending on an amplitude of the vibration, and a second front fork (10) which generates a damping force for damping a vibration of the front wheel not depending on the amplitude of the vibration. By thus combining the front forks (10, 20) having different damping force characteristics, the front wheel supporting structure can absorb vibrations of various velocities and amplitudes.
    Type: Grant
    Filed: September 12, 2007
    Date of Patent: June 22, 2010
    Assignee: Kayaba Industry Co., Ltd.
    Inventor: Hideo Inaguma
  • Patent number: 7690667
    Abstract: A bicycle shock absorber and methods for differentiating between rider-induced forces and terrain-induced forces includes a first fluid chamber having fluid contained therein, a piston for compressing the fluid within the fluid chamber, a second fluid chamber coupled to the first fluid chamber by a fluid communication hose, and an inertial valve disposed within the second fluid chamber. The inertial valve opens in response to terrain-induced forces and provides communication of fluid compressed by the piston from the first fluid chamber to the second fluid chamber. The inertial valve does not open in response to rider-induced forces.
    Type: Grant
    Filed: April 30, 2009
    Date of Patent: April 6, 2010
    Assignee: Specialized Bicycle Components, Inc.
    Inventor: Michael McAndrews
  • Patent number: 7523818
    Abstract: A vibration damper with amplitude-selective damping force includes a cylinder containing a damping medium, a piston rod which is axially movable in the cylinder, and a piston assembly arranged for axial movement in the damping medium, the piston assembly being connected to the piston rod and dividing the cylinder into a working space around the piston rod and a working space opposite the piston rod, the piston assembly includes a piston body having connecting channels for opposite directions of flow between the working spaces, and valve disks which open the channels in respective opposite directions. A pilot assembly includes an axially movable shifting ring which controls a flow connection between the working spaces as a function of movement of the piston rod, and a pair of stop surfaces which limit axial movement of the shifting ring, wherein the stop surfaces are independent of the piston body and the valve disks.
    Type: Grant
    Filed: December 7, 2005
    Date of Patent: April 28, 2009
    Assignee: ZF Friedrichshafen AG
    Inventors: Thomas Hammer, Michael Doppernas, Matthias Planitzer, Manfred Denner
  • Patent number: 7438164
    Abstract: A shock absorber includes a pressure tube with a piston slidably disposed therein. A separate valve includes a fluid circuit for fluid low in rebound and a fluid circuit for fluid flow in compression. Each fluid circuit includes a variable orifice which allows selection between a firm rebound with a soft compression, a soft rebound with a soft compression and a soft rebound with a firm compression. Each variable orifice is in communication with a blowoff valve in such a manner that they provide a variable blowoff feature to the blowoff valves.
    Type: Grant
    Filed: December 8, 2003
    Date of Patent: October 21, 2008
    Assignee: Tenneco Automotive Operating Company Inc.
    Inventors: Gary W Groves, Karl Kazmirski, David L Steed, Michael L Zebolsky
  • Patent number: 7320388
    Abstract: A two-stage shock absorber has a pressure tube within which a valve assembly is slidably disposed. A piston rod is attached to the valve assembly and extends out of the pressure tube. A ring is slidably disposed within the pressure tube and engages the valve assembly. After a specified amount of movement of the valve assembly with respect to the pressure tube in an extension movement of the shock absorber, the sleeve engages a plurality of spirally positioned bores and reduces the fluid flow through the valve assembly to progressively switch the shock absorber from soft damping to firm damping. In another embodiment the sleeve engages a spiral groove of variable depth to reduce the fluid flow through the valve assembly to progressively switch the shock absorber from soft damping to firm damping.
    Type: Grant
    Filed: September 15, 2003
    Date of Patent: January 22, 2008
    Assignee: Tenneco Automotive Operating Company Inc.
    Inventor: Simon A de Molina
  • Patent number: 7293634
    Abstract: A hydraulic shock absorber comprises a cylindrical chamber (3), which is closed at one end and in which is axially slidably guided a piston member 85), supported by a piston rod (8) and at its peripheral surface carrying a surrounding non-slotted elastic ring element (6), the peripheral piston member surface being conically converging in a direction away from the closed chamber end and the inner surface of the ring element also conically converging in the same direction, the ring element (6) furthermore being axially reciprocably mounted on the piston member (5) between a first rigid abutment 84) at the end of said member (5) closest to the closed and (10) of the chamber (3), and a second rigid abutment (7) on the piston member (5) at a spacing from the first abutment (4) exceeding the axial length of the ring element (6).
    Type: Grant
    Filed: July 12, 2002
    Date of Patent: November 13, 2007
    Assignee: ASA-Suspension AB
    Inventor: Jan-Erik Rova
  • Patent number: 6981578
    Abstract: A shock absorber of a monotube type utilizes a mechanically fixed base valve to regulate oil flow between the compression and compensation chambers, and a compressible bladder in the compensation chamber to allow volume compensation, which, together, eliminate the need for pressurized gas and a floating piston found in conventionally known monotube dampers.
    Type: Grant
    Filed: July 16, 2004
    Date of Patent: January 3, 2006
    Inventors: Troy Leiphart, James D. Hansen
  • Publication number: 20040163905
    Abstract: A position-sensitive shock absorbing device with a single cast body construction is provided. The device has a tubular member, a moveable piston within the tubular member, a first hydraulic fluid chamber defined by an interior volume of the tubular member, a bypass member attached to an outside area of the tubular member. The bypass member surrounds a portion of the tubular member and a second hydraulic fluid chamber is defined by a volume between the tubular member and the bypass member. A first and a second opening in a side of the tubular member are arranged such that the openings are fluidly connected with each other and with both the first and second hydraulic fluid chamber.
    Type: Application
    Filed: February 24, 2003
    Publication date: August 26, 2004
    Inventors: Douglas K. Braswell, Del R. Nelson, Brian W. Dick
  • Publication number: 20030132072
    Abstract: In one embodiment, a suspension system includes a hydraulic assembly. A cylindrical spacer is attached to the hydraulic assembly. An annular seating member is removably coupled to the cylindrical spacer and supports a biasing member. In another embodiment, the annular seating member is coupled to the hydraulic assembly. A support member is removably coupled to the cylindrical assembly.
    Type: Application
    Filed: April 25, 2002
    Publication date: July 17, 2003
    Inventors: Seiji Sawai, Kouji Sakai
  • Publication number: 20020104722
    Abstract: Vibration damper comprising a damping medium-filled pressure tube, in which a displacer is installed, where a damping device produces a damping force as a function of the movement of the displacer. A damping force-limiting device, independently of the flow of the damping medium, becomes active above a certain damping force threshold value, which is defined as a function of the vehicle. At least a partial section of the force-limiting device is connected in a fixed manner to the pressure tube below the damping force threshold value and travels an operating distance which is associated with a change in the volume of the pressure tube when the force threshold is exceeded.
    Type: Application
    Filed: February 4, 2002
    Publication date: August 8, 2002
    Applicant: ZF Sachs AG
    Inventors: Dieter Lutz, Gottfried Zimmermann
  • Patent number: 6427986
    Abstract: An air chamber (53) of a damping force adjusting mechanism (49) disposed in a hydraulic shock absorber (3) of a damping force adjusting type communicates with an air chamber (7) of an air spring through a tubular path (57). A free piston (51) is transferred in accordance with the pressure of the air chamber and a spool (46) is transferred to shift a damping force. The damping force presents a soft characteristic both on the extending side and on the retracting side in a usual status, presents a hard characteristic on the extending side and a soft characteristic on the retracting side when the pressure of the air chamber is high, and presents a soft characteristic on the extending side and a hard characteristic on the retracting side when the pressure of the air chamber (7) is low. The damping force can be obtained, which approximates the damping force control on the basis of a so-called sky-hook theory.
    Type: Grant
    Filed: March 30, 2000
    Date of Patent: August 6, 2002
    Assignee: Tokico, Ltd.
    Inventors: Hiroshi Sakai, Akinori Kurusu, Nobuyuki Ichimaru, Takao Kohara, Satoshi Ohsawa
  • Patent number: 6412614
    Abstract: A shock absorber for damping shock energy generated by downhole perforating guns or stimulation devices is described. The shock absorber includes a spring assembly including at least a first spring and a second spring, the first spring having a tension greater than the second spring; a damper assembly; and a housing retaining the spring assembly and the damper assembly and including ends adapted for connection into a casing perforation assembly. The provision of springs of increasing stiffness permits the force generated by the perforating gun to be absorbed gradually and smoothly.
    Type: Grant
    Filed: September 20, 1999
    Date of Patent: July 2, 2002
    Assignees: Core Laboratories Canada Ltd., Computalog Ltd.
    Inventors: Timothy Edward Lagrange, Andrew Antoine Buzinsky, David O. Carlson
  • 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
  • Patent number: 6412606
    Abstract: A damper includes a barrel axially slidably mounted on a shaft, an elastic ring mounted inside the barrel around the shaft, arched pressure blocks mounted abutted against one another inside the elastic ring around the shaft, each arched pressure block having an axially extended sloping groove, steel balls respectively arranged in the sloping groove of each arched pressure block in contact with the periphery of the shaft, a rigid locating ring mounted inside the barrel to support the steel balls in the sloping groove of each arched pressure block, a screw cap threaded into one side of the barrel, a compression spring stopped between the screw cap and the locating ring, a hollow adjustment screw member threaded into one side of the barrel to support the steel balls in the sloping groove of each arched pressure block against the locating ring.
    Type: Grant
    Filed: October 3, 2001
    Date of Patent: July 2, 2002
    Inventor: Chun-Liang Wu
  • Patent number: 6390257
    Abstract: A suspension damper or shock absorber for a vehicle suspension system includes a piston assembly across which damping fluid is metered to control relative movement between the vehicle body and chassis. The piston assembly includes a piston plate in which a first set of openings are provided for fluid communication during the rebound stroke of the piston assembly and a second set of openings for communication of damping fluid during the opposite compression stroke. A wall circumscribes the first set of openings to define a recess receiving damping fluid from the first set of openings. A valve disc engages the wall and opens at a predetermined pressure differential. At pressure differentials less than the predetermined pressure differential, highly restricted flow is permitted through a bypass passage formed by a coined depression in the rim of the wall having a continuously curved, preferably semicircular cross section, to provide damping for low level inputs.
    Type: Grant
    Filed: February 16, 2000
    Date of Patent: May 21, 2002
    Assignee: Delphi Technologies, Inc.
    Inventor: Mark R. Naples
  • Patent number: 6390457
    Abstract: A gas spring includes an outer tube; a base plate; a head plate; an inner tube mounted to extend between the head plate and the base plate; a piston/rod assembly mounted to reciprocate vertically in the inner tube between a retracted, compressed position and an extended, rest position; a valve ring coaxially mounted around the rod to reciprocate between the main piston and head plate; a primary gas chamber; a relief chamber; seals for preventing fluid flow from the primary and relief chambers; a passageway providing communication between the primary gas chamber and relief chamber; and, valve apparatus for controlling fluid flow between the primary and relief chambers. The valve apparatus operates to open and close the fluid flow as a function of the position and direction of travel of the piston/rod assembly.
    Type: Grant
    Filed: February 14, 2001
    Date of Patent: May 21, 2002
    Inventor: Ralph Roper
  • Patent number: 6382373
    Abstract: A gas shock absorber has a pressure tube which defines a working chamber. A piston divides the working chamber into an upper working chamber and a lower working chamber. A series of extension passages extend through the piston and are opened and closed by an extension valve assembly. A series of compression passages extend through the piston and are opened and closed by a compression valve assembly. An open flow path defined by the extension valve assembly extends through the piston between the upper and lower working chambers. A rod guide assembly is located between the pressure tube and a piston rod. The rod guide assembly includes an oil chamber for sealing and lubricating the piston rod.
    Type: Grant
    Filed: September 20, 1999
    Date of Patent: May 7, 2002
    Assignee: Tenneco Automotive Inc.
    Inventors: Luc Lemmens, Stefaan Duym
  • Patent number: 6374966
    Abstract: The housing of a shock absorber is constructed to include an inner chamber surrounded by an outer chamber. The inner chamber is divided by the piston to which the piston rod is connected into two portions. One of these portion has a number of orifices that fluidly connect that portion to the outer chamber. A piston slidably and movably fitted along the length of the outer chamber divides the outer chamber into two compartments, one of which is in fluid communication with the portion of the inner chamber to which it is connected by means of the orifices. An incompressible fluid is provided in the fluidly interconnected compartment and portion. A biasing force acts against the piston in the outer chamber by means of a pressurized gas provided in the other compartment of the outer chamber. With the shock absorber thus constructed, when the piston rod moves, the piston to which it is connected would force an exchange of fluid between the inner chamber and the outer chamber, which acts as a reservoir.
    Type: Grant
    Filed: November 29, 1999
    Date of Patent: April 23, 2002
    Assignee: Lillbacka Jetair Oy
    Inventor: Jorma Lillbacka
  • Patent number: 6360857
    Abstract: A shock absorber comprises an adjustment component movable in two degrees of freedom. When the adjustment component is adjusted within one of its degrees of freedom of movement, a characteristic, such as the compression damping, is adjusted and when the adjustment component is adjusted within the other of its degrees of freedom of movement another characteristic, such as the rebound damping, is adjusted. The invention extends to a method of adjusting the operation of a shock absorber.
    Type: Grant
    Filed: March 8, 2000
    Date of Patent: March 26, 2002
    Assignee: Fox Factory, Inc.
    Inventors: Robert C. Fox, John Marking
  • Patent number: 6352145
    Abstract: A two-stage shock absorber has a pressure tube within which a valve assembly is slidably disposed. A piston rod is attached to the valve assembly and extends out of the pressure tube. A ring is slidably disposed within the pressure tube and engages the valve assembly. After a specified amount of movement of the valve assembly with respect to the pressure tube in an extension movement of the shock absorber, the sleeve engages a metered slot and reduces the fluid flow through the valve assembly to progressively switch the shock absorber from soft damping to firm damping.
    Type: Grant
    Filed: October 7, 1998
    Date of Patent: March 5, 2002
    Assignee: Tenneco Automotive Inc.
    Inventors: Simon Anne DeMolina, Karl C. Kazmirski
  • Publication number: 20020003072
    Abstract: Shock absorber, having a cylinder in which a piston rod is arranged as a displacer and which has a piston which subdivides a working space filled with damping medium into two working chambers. Arranged concentrically with this cylinder is an outer tube which, together with the cylinder, forms an annular space sealed off from the atmosphere by seals. The outer tube, together with the piston rod, executes a synchronous movement relative to the cylinder as a function of the reciprocating movement. At least one of the seals of the annular space is arranged in a fixed location with respect to the cylinder, and at least another one of the seals is arranged in a fixed location with respect to the outer tube, so that the annular space has a volume which varies as a function of the reciprocating position of the shock absorber. The annular space is connected via at least one flow connection to at least one of the working chambers.
    Type: Application
    Filed: May 30, 2001
    Publication date: January 10, 2002
    Applicant: Sachs Race Engineering GmbH
    Inventors: Theo Rottenberger, Markus Reinhart
  • Patent number: 6298959
    Abstract: A motion-restraining arrangement is described, which has a motion restrainer, which has a housing that is essentially stationary. It includes a restraining device, and a connecting member movable relative to the housing. The housing can be connected to a movable part to be restrained in its movement. Furthermore a switch having two contacts is connected to the housing. The operating member for the switch is provided on the connecting member. The switch may be operated by the operating member pressing contacts against one another.
    Type: Grant
    Filed: June 16, 2000
    Date of Patent: October 9, 2001
    Assignee: Hoerauf & Kohler Verwaltungs KG
    Inventors: Wilfried Willner, Hans Possler, Christof Oles
  • Patent number: 6206152
    Abstract: A vibration damper with variable damping force, including a cylinder, in which a piston with a piston rod is arranged in axially movable fashion, whereby an adjustable damping valve is activated in dependence on the deflection distance and the activation of the adjustable damping valve is carried out via a stabilizer. The vibration damper has further damping valves, whose damping effects are independent of activation by the stabilizer. The adjustable damping valve, during equilateral deflection and rebound travel of the piston rod on a vehicle axle or unilateral rebound travel, has a damping force setting that is smaller than the damping force of the further damping valves of the vibration damper.
    Type: Grant
    Filed: March 8, 1999
    Date of Patent: March 27, 2001
    Assignee: Mannesmann Sachs AG
    Inventors: Manfred Grundei, Otto Samonil
  • Patent number: 6182575
    Abstract: The invention relates to adjustable stop-wagon retarders with locking function for wagons at high speed and disposal methods thereof, which are suitable for railway marshaling yards or rail lines where it is required to prevent wagons from running away, which are hydraulic equipment of no external energy source to automatically regulate wagon's speed and disposal methods of such equipment. The stop-wagon retarder is characterized in that a uni-directional return unit comprising a sealing valve plate and adjustable throttle valve, and a locking control valve composing of switch valve and positioning unit are mounted in the piston assembly, which make the returning speed and the locking speed for wagon at high speed adjustable, thus the aim of setting the retarder with different control levels and thresholds according to the wagon speed is realized.
    Type: Grant
    Filed: August 6, 1998
    Date of Patent: February 6, 2001
    Assignee: China TDJ System Research Centre
    Inventors: Yongting Liu, Qian Wang, Lining Wang, Mingzhu Wang, Hongbo Yu, Peiwen Chang, Libin Zhang
  • Patent number: 6129343
    Abstract: A gas spring comprising a cylindrical body in which a main piston is slidable and carries a piston rod extending in sealed manner outwardly of the cylinder. The main piston includes a bore connecting with a labyrinthine passageway. The interior of the cylinder contains a fluid comprising gas under pressure and (optionally) some oil. The gas urges the piston rod outwardly of the cylinder. During the corresponding travel of the piston, the fluid transfers from one side of the piston to the other in a controlled manner through the bore and the passageway to allow relatively rapid travel. However, when the main piston comes into contact with a second piston, freely slidable on the piston rod and biassed towards the main piston by a compression spring, this contact closes off the end of the fluid passageway, and fluid can now only transfer through the main piston by passing through a narrow radial channel, thus reducing the speed of outward travel of the piston rod.
    Type: Grant
    Filed: May 19, 1998
    Date of Patent: October 10, 2000
    Assignee: Draftex Industries Limited
    Inventor: Eric Ecarnot
  • Patent number: 5957252
    Abstract: An improved hydraulic suspension unit has a springing force and rebound damping which are related to one another so as to allow certain wheel movements to occour without the resistance of rebound damping. A primary springing force provided by a pressurized gas, a coil spring and elastomer or any combination therof acts directly through the shock fluid via a floating piston, bladder or flexible diaphragm. The primary spring force acts directly through the shock fluid, and thus directly on a rebound damping valve so that the rebound damping valve is only able to dampen the stored energy. The spring provides a maximun in tuning and adjustment capability for varying conditions with easily variable reload and rate. The rebound damping valve can also be adjusted, both to determine the maximum rebound resistance when damping springing energy, and thus maximum shock shaft velocity, and to determine the magnitude of th shaft movements that are allowed to occur without rebound damping.
    Type: Grant
    Filed: August 2, 1996
    Date of Patent: September 28, 1999
    Inventor: Brian D. Berthold
  • Patent number: 5927448
    Abstract: A shock absorber capable of exhibiting increased shock absorbing characteristics and constantly ensuring desired characteristics irrespective of applications intended. A cylinder is formed therein with a first hollow section of a large diameter and a second hollow section of a small diameter. A piston includes an end wall and a peripheral wall and is formed into a size sufficient to be moved in the second hollow section. The peripheral wall is formed with a plurality of orifices and the end wall is formed with a piston rod insertion through-hole and at least one viscous fluid passage hole. The piston rod is provided thereon with first and second flanges, which are spaced from each other at an interval larger than a thickness of the end wall of the piston and arranged so as to interpose the end wall therebetween.
    Type: Grant
    Filed: March 10, 1997
    Date of Patent: July 27, 1999
    Assignee: Fuji Seiki Kabushiki Kaisha
    Inventor: Fumio Yamazaki
  • Patent number: 5890568
    Abstract: A twin-tube shock damper has a hollow piston rod (5) which extends towards the top of the working cylinder (1), a baseplate (8) which closes off the working cylinder and a disc (7) which is arranged inside the working cylinder between the piston (4) and the baseplate and has one or more passages (16) and a non-return valve (17) which allows upward flow through the passages, a central tube (10), a connection (11) between the hollow piston rod and the space above the piston, a damping valve (21) which operates in one direction of flow and servo-control means having an excitation chamber (18) and an excitable coil (30). A control valve in the form of a hollow piston (25) movable in a control valve cylinder (22) provided with orifices (24) and a hollow shaft (27) guided in a valve shaft guide (26) provided with orifices (28) are located in the excitation chamber. Both the control valve cylinder and the control valve are pushed by spring means (23, 29) in the direction of the damping valve body (17).
    Type: Grant
    Filed: June 9, 1997
    Date of Patent: April 6, 1999
    Assignee: Koni B.V.
    Inventors: Cornelis De Kock, Paul De Kock
  • Patent number: 5845749
    Abstract: A linear motion absorber for damping linear movement utilizing a cylinder having a reciprocal piston located therein. The cylinder and piston are molded of synthetic plastic and the piston is of an extended length and a diameter slightly less than the inner diameter of the cylinder as to be self aligning therewith and includes a homogeneous annular lip seal to produce unidirectional sealing. The piston stem or rod is also of a synthetic plastic material and in the rigid stem embodiment homogeneously extends from the piston. The piston rod may also consist of a flexible synthetic strand attached to the piston for transmitting tension forces, and a compression spring within the cylinder acting upon the piston will position the piston to a retracted position. The open end of the cylinder is sealed by a removable cap entirely formed of a synthetic plastic material which may be readily affixed to the cylinder to produce a closed circuit during damping.
    Type: Grant
    Filed: October 11, 1995
    Date of Patent: December 8, 1998
    Assignee: TMJ Properties, L.L.C.
    Inventors: Ralph D. Moretz, William D. Solomon, Ronald L. Johncox
  • Patent number: 5781873
    Abstract: In apparatus and method for controlling a damping force characteristic for a vehicular suspension system, a control force (F) based on an ideal Sky Hook theory is generated even when a low responsive characteristic and less expensive actuator such as a stepping motor associated with an adjuster of each shock absorber and which is not enabled to respond to an unsprung mass resonance frequency and a control signal based on a sprung mass vertical velocity and on a relative velocity between a vehicle body (sprung mass) and a road wheel assembly (unsprung mass) is formed using a signal processing circuit so that the control signal is formed in a low frequency band. The damping force characteristic of each shock absorber is controlled on the basis of the formed control signal.
    Type: Grant
    Filed: September 29, 1995
    Date of Patent: July 14, 1998
    Assignee: Unisia Jecs Corporation
    Inventor: Mitsuo Sasaki
  • Patent number: 5535861
    Abstract: A plurality of embodiments of dual-rate linear dampers which can be utilized as hold open rods. These dampers provide significantly greater resistance to movement in one direction than in the other and, in one embodiment, effectively lock in the hold open position unless and until the design breakover force is incurred. The comparative resistance to movement in the two linear directions can be altered within the range of between five and ten times the force in the resistive embodiment by varying a number of parameters including, but not limited to, the number of disks in the string, the thickness of the disk flange, the number and depth of grooves in one or both surfaces of the flange, the tapering of the flange, and the properties of the elastomer.
    Type: Grant
    Filed: June 8, 1995
    Date of Patent: July 16, 1996
    Assignee: Lord Corporation
    Inventor: Robert A. Young
  • Patent number: 5458218
    Abstract: A suspension system with at least one hydraulic spring strut. At least a portion of the hydraulic medium is displaced into a hydropneumatic spring reservoir during the compression movement of the spring strut, and that portion of the hydraulic medium flows back into the spring strut during the expansion movement. At least the expansion flow is conveyed through the flow path of a damping valve and damped due to the fact that the flow path is continuously closed and reopened in an alternating fashion by means of a valve element once a expansion flow is present. The valve element is bypassed via a bypass which is constructed in such a way that a pressure compensation between the sections of the flow path arranged on both sides of the valve element is ensured in the static condition in which essentially no flow is present; and that the bypass essentially loses this pressure compensation function in the dynamic condition in which a flow is present.
    Type: Grant
    Filed: December 14, 1993
    Date of Patent: October 17, 1995
    Assignee: Hemscheidt Fahrwerktechnik GmbH & Co. KG
    Inventor: Walter Runkel
  • Patent number: 5454451
    Abstract: In order to develop sufficient vibration damping performance and effectively prevent transmission of goading vibrations and others in a vibration damping device using an electrorheological fluid, if the moving directions of vibration input side member and vibration output side member of the device are opposite to each other, a voltage applied to electrodes in the device is increased to increase the viscosity of the electrorheological fluid, while if absolute value of vibration acceleration velocity in the vibration input side member exceeds a given value, a voltage applied to the electrodes is always decreased to decrease the viscosity of the fluid.
    Type: Grant
    Filed: December 24, 1992
    Date of Patent: October 3, 1995
    Assignee: Bridgestone Corporation
    Inventors: Satoru Kawamata, Masatoshi Ohishi, Norio Nihei, Takeshi Kimura
  • Patent number: 5363945
    Abstract: A direct acting shock absorber for damping the movement of the body of an automobile is disclosed. The shock absorber comprises a pressure cylinder forming a working chamber having first and second portions operable to store damping fluid. A piston is disposed within the pressure cylinder between the first and second portions of the working chamber. The shock absorber further comprises a fluid reservoir operable to store damping fluid. The shock absorber also includes a valve for permitting damping fluid to flow from the first portion of the working chamber to the fluid reservoir during movement of the piston in a first direction. Finally, a second valve is provided for permitting damping fluid to flow from the fluid reservoir to the second portion of the working chamber during movement of the piston in a second direction.
    Type: Grant
    Filed: May 7, 1993
    Date of Patent: November 15, 1994
    Assignee: Monroe Auto Equipment Company
    Inventors: Magnus B. Lizell, Bert Vanroye
  • Patent number: 5328004
    Abstract: A hydraulic suspension damper includes a fluid-filled cylinder divided into first and second fluid chambers by a reciprocating piston. A bypass valve assembly includes a first pressure responsive valve assembly in fluid connection with one of the fluid chambers and a second pressure responsive valve assembly in fluid connection with the other fluid chamber. The pressure responsive valve assemblies direct fluid to an unidirectional electromechanical valve assembly. Operation of the bypass valve assembly permits independent control of fluid during compression and rebound strokes of the damper.
    Type: Grant
    Filed: August 21, 1992
    Date of Patent: July 12, 1994
    Assignee: General Motors Corporation
    Inventors: Wayne V. Fannin, James M. Pees
  • Patent number: 5257680
    Abstract: Several improved embodiments of surface effect dampers that produce a damping force including both hysteretic and frictional components. Various improvements include an amplitude sensitive feature or decoupler mechanism to eliminate or greatly reduce the damping for low amplitude input conditions as compared to high amplitude inputs, provisions for increasing the damping force in a non-linear manner, and features for providing significantly greater damping in one direction than the other. Other embodiments include an improved rotational surface effect damper useful for damping rotational motion, and a multiaxial damper which can be used, for example, as a motor mount which has the capability for the piston to tilt relative to the axis of its piston rod, allowing accommodation of torsional rotation of the engine while not compromising vibration isolation.
    Type: Grant
    Filed: December 20, 1991
    Date of Patent: November 2, 1993
    Assignee: Lord Corporation
    Inventors: Patrick E. Corcoran, Richard P. Thorn
  • Patent number: 5230407
    Abstract: A linkage rod for absorbing shocks and vibrations has a housing with a central bore. A spacer tube and a spacer load plate are inserted into the central bore. Several resilient members preferably formed of crimped metal wire strands are located in the central bore between the spacer load plate and a piston load plate. A mounting member has a shoulder formed between body and neck portions. A snubber cap having a central opening with an inwardly-directed wall is positioned around the mounting member. A snubber nut is attached to the mounting member to trap the inwardly-directed wall between the snubber nut and the shoulder. The snubber cap is fastened to the housing and the mounting member may move axially relative to the housing. The resilient members resist axial movement of the mounting member.
    Type: Grant
    Filed: May 22, 1992
    Date of Patent: July 27, 1993
    Assignee: Applied Power Inc.
    Inventors: Gary T. Smith, William S. Jensen, Edwin Banks, Andy Pork, Michael R. Teeter
  • Patent number: 5211268
    Abstract: A direct acting shock absorber for damping the movement of the body of an automobile is disclosed. The shock absorber comprises a pressure cylinder forming a working chamber having first and second portions operable to store damping fluid. A piston is disposed within the pressure cylinder between the first and second portions of the working chamber. The shock absorber further comprises a fluid reservoir operable to store damping fluid. The shock absorber also includes a valve for permitting damping fluid to flow from the first portion of the working chamber to the fluid reservoir during movement of the piston in a first direction. Finally, a second valve is provided for permitting damping fluid to flow from the fluid reservoir to the second portion of the working chamber during movement of the piston in a second direction.
    Type: Grant
    Filed: July 9, 1990
    Date of Patent: May 18, 1993
    Assignee: Monroe Auto Equipment Company
    Inventors: Magnus B. Lizell, Bert Vanroye
  • Patent number: 5133435
    Abstract: A dry friction shock absorber including a casing having an internal surface, a piston of low coefficient of friction bearing material having an external surface in contiguous relationship with the internal surface of the casing, attachment fittings on the piston and the casing for moving the piston into the casing when the shock absorber is subjected to shock forces, and expanding structure within the piston for tending to move the external surface of the piston outwardly toward the internal surface of the casing to increase the friction therebetween when the shock absorbing force is applied to the shock absorber for moving the piston into the casing. Adjustment structure is provided for varying the expanding force on the piston. A shock absorber of the foregoing type wherein the expanding structure is not activated when the piston moves slowly relative to the casing but which produces an expanding force on the piston when the shock absorber is subjected to shock forces both in tension and compression.
    Type: Grant
    Filed: December 20, 1989
    Date of Patent: July 28, 1992
    Assignee: Tayco Developments, Inc.
    Inventor: Paul H. Taylor
  • Patent number: 4955460
    Abstract: A direct acting shock absorber for damping the movement of the body of an automobile is disclosed. The shock absorber comprises a pressure cylinder forming a working chamber having first and second portions operable to store damping fluid. A piston is disposed within the pressure cylinder between the first and second portions of the working chamber. The shock absorber further comprises a fluid reservoir operable to store damping fluid. The shock absorber also includes a valve for permitting damping fluid to flow from the first portion of the working chamber to the fluid reservoir during movement of the piston in a first direction. Finally, a second valve is provided for permitting damping fluid to flow from the fluid reservoir to the second portion of the working chamber during movement of the piston in a second direction.
    Type: Grant
    Filed: March 13, 1989
    Date of Patent: September 11, 1990
    Assignee: Monroe Auto Equipment Company
    Inventors: Magnus B. Lizell, Albert E. Vanroye
  • Patent number: 4948103
    Abstract: A spring-loaded dampening actuator includes a cylindrically-shaped body member, a piston rod, a coil spring, and a one-way lip seal member. The lip seal member engages an inner sidewall of the body member only when a force is applied by means of a coil spring so as to push the piston rod out from the body member at a dampened or controlled rate of speed.
    Type: Grant
    Filed: January 30, 1989
    Date of Patent: August 14, 1990
    Assignee: Illinois Tool Works, Inc.
    Inventors: Patrick J. Bowden, Beryle S. Doyle
  • Patent number: 4834088
    Abstract: A shock absorber for vehicles with pneumatic suspension, particularly for use with heavy vehicles, of the type comprising a cylinder, a rod movable axially in the cylinder, a piston carried by the rod and dividing the cylinder into a cylindrical chamber and an annular chamber, a pressurized fluid filling the cylindrical and annular chambers, a first circuit for allowing the fluid to flow from the annular chamber to the cylindrical chamber when the shock absorber is working under extension, a second circuit for allowing the fluid to flow from the cylindrical chamber to the annular chamber when the shock absorber is working under compression, a pressurized fluid reservoir connectable to the cylindrical and annular chambers and flow regulators mounted in the first and second circuits, the flow regulators being controlled by the fluid pressure against the action of the pressure of the compressed air of the pneumatic suspension of the vehicle.
    Type: Grant
    Filed: March 1, 1988
    Date of Patent: May 30, 1989
    Assignee: Jimecal
    Inventor: Henri R. Jeanson
  • Patent number: 4817766
    Abstract: The invention relates to an arrangement for damping shifting movements in a mechanical, synchronized multispeed transmission. Where such shifting movements are performed with the aid of a servo-mechanism, for exmaple a pneumatic piston cylinder unit, there is the risk that the gear teeth will be damaged when brought into engagement with each other. In the arrangement according to the invention, a pressure medium-filled damper is used without any communication with a separate pressure medium reservoir, thus eliminating the risk of malfunction due to foam formation in the pressure medium as well as achieving a desirable damping of the shifting movement. The invention is characterized for this purpose in that the piston in the damper is arranged on a piston rod which extends through the cylinder portion of the damper, so that upon relative movement between the piston and the cylinder portion, the volume of the damper filled with pressure medium remains constant.
    Type: Grant
    Filed: March 2, 1988
    Date of Patent: April 4, 1989
    Assignee: Saab-Scania Aktiebolag
    Inventor: Nils H. Nilsson
  • Patent number: 4785922
    Abstract: A constant-pressure hydraulic shock-absorbing device suitable for use as a recoil brake in a weapon system. By use of a piston that decreases in diameter as the applied force increases, a constant resistive force independent of the applied force is obtained. The varying diameter of the piston creates a varying aperture for the displacement of fluid by the piston, thus varying the resistive force. This results in minimum travel and/or minimum/maximum force transmitted through the shock absorber for a given applied energy.
    Type: Grant
    Filed: October 2, 1987
    Date of Patent: November 22, 1988
    Inventor: Lawrence R. Kiehart
  • Patent number: 4703838
    Abstract: A recoil damper (10) for a reciprocating member (12) mounted in a housing (24) includes a annular ring (38,138) mounted adjacent a shoulder (28) formed on the reciprocation member, the annular ring (38,138) mounted in a viscous fluid interior of the housing. The annular ring (38,138) cooperates with the shoulder (28) of the reciprocating member (12) to allow a relatively free flow of the viscous fluid around the shoulder (28) upon motion of the reciprocating member (12) in one direction and to restrict flow of the viscous fluid around the shoulder (28) upon motion of the reciprocating member (12) in the other opposite direction.
    Type: Grant
    Filed: September 25, 1982
    Date of Patent: November 3, 1987
    Assignee: Caterpillar Tractor Co.
    Inventors: Michael A. Roussin, Delwin E. Cobb
  • Patent number: 4651979
    Abstract: For a temperature-compensated gas spring, which consists of a container in which a concentrically arranged cylinder is arranged, where a main pressure chamber is separated in sealing manner from an auxiliary pressure chamber by a piston which is connected with a piston rod, a damping arrangement is provided for controlling the outward thrust speed. This is effected in that a damping chamber is arranged in which a damping piston provided with damping valves slides, the damping piston being arranged on an auxiliary piston rod which is in axially fixed connection with the piston rod.
    Type: Grant
    Filed: September 4, 1985
    Date of Patent: March 24, 1987
    Assignee: Stabilus GmbH
    Inventors: Herbert Freitag, Castor Fuhrmann, Bernd Kortgen
  • Patent number: 4647026
    Abstract: In a pneumatic or hydropneumatic tension spring which consists of a container in which a cylinder is concentrically arranged and a liquid and/or gas filling under pressure has an inward force upon a piston rod, between a working chamber on the piston rod side and an annular chamber a damper device is arranged which generates a greater damping effect in the inward movement of the piston rod than in the outward movement of the piston rod. Due to this measure a damped inward movement of the piston rod is achieved while the extraction of the piston rod can be effected without appreciable damping.
    Type: Grant
    Filed: September 4, 1985
    Date of Patent: March 3, 1987
    Assignee: Stabilus GmbH
    Inventors: Martin Siemann, Wolfgang Luhn
  • Patent number: 4623049
    Abstract: Tubular members (22, 24) define a pressure chamber (26) and a reserve chamber (28) between them. A first variable metered hydraulic orifice area is provided between chambers (26, 28) by openings (32) in a metering tube (30). A second metered hydraulic orifice area is provided by fixed orifice (94). In a first mode of operation, both such areas are open during an initial retraction of members (22, 24). Control tube (34) is coaxial with metering tube (30) and has openings (36). In the first mode, latch (62) locks tubes (30, 34) together with openings (32, 36) aligned. Relative extension of members (22, 24) following the initial retraction causes pressure in chamber (28) to rise above pressure in chamber (26) and latch (62) to release control tube (34). Spring (40) moves tube (34) into a closed position in which it blocks openings (32). Shock absorber (20) then operates in its second mode in which fixed orifice (94) remains open and openings (32) remain closed.
    Type: Grant
    Filed: August 1, 1985
    Date of Patent: November 18, 1986
    Assignee: The Boeing Company
    Inventor: Steven M. Warren
  • Patent number: 4583621
    Abstract: An oscillation damping device having a differentiated action in the two directions of sliding of a rigid stem with respect to a rigid case, comprising a plurality of rigid rolling elements, interposed between a rolling race of viscoelastic material and one or more skidding metallic races, shaped in such a way that upon moving the stem in one direction, the rolling elements are encased within said metallic races, spaced out from the viscoelastic race and exert a limited braking effect, while upon moving the stem in the opposite direction, the rolling elements are advanced into interference with the viscoelastic race and thereby exert a strong braking effect.
    Type: Grant
    Filed: March 19, 1984
    Date of Patent: April 22, 1986
    Assignee: Industrie Pirelli S.p.A.
    Inventor: Giorgio Tangorra
  • Patent number: 4443926
    Abstract: A method of assembly of a shock absorber is disclosed. A cell, formed of plys of polymeric material impervious to hydraulic fluid and a high molecular gas, while pervious to air and water vapor, is wrapped about the inner tubular container, secured thereto by clips at a midsection of the cell, and effectively inserted into the outer tubular container even though the cell contains a predetermined quantity of gas. The containers can preferably be filled with hydraulic fluid prior to insertion.
    Type: Grant
    Filed: February 8, 1982
    Date of Patent: April 24, 1984
    Assignee: Ford Motor Company
    Inventors: Robert M. Pearson, Robert J. Womac