WO2012173550A1 - Device for damping of a piston inside a cylinder housing - Google Patents

Device for damping of a piston inside a cylinder housing Download PDF

Info

Publication number
WO2012173550A1
WO2012173550A1 PCT/SE2012/050561 SE2012050561W WO2012173550A1 WO 2012173550 A1 WO2012173550 A1 WO 2012173550A1 SE 2012050561 W SE2012050561 W SE 2012050561W WO 2012173550 A1 WO2012173550 A1 WO 2012173550A1
Authority
WO
WIPO (PCT)
Prior art keywords
damping
piston
cylinder
recess
protrusion
Prior art date
Application number
PCT/SE2012/050561
Other languages
French (fr)
Inventor
Jan Erik ROVA
Original Assignee
Asa-Suspension Ab
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Asa-Suspension Ab filed Critical Asa-Suspension Ab
Priority to EP12800071.8A priority Critical patent/EP2721307A4/en
Publication of WO2012173550A1 publication Critical patent/WO2012173550A1/en

Links

Classifications

    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B15/00Fluid-actuated devices for displacing a member from one position to another; Gearing associated therewith
    • F15B15/20Other details, e.g. assembly with regulating devices
    • F15B15/22Other details, e.g. assembly with regulating devices for accelerating or decelerating the stroke
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B15/00Fluid-actuated devices for displacing a member from one position to another; Gearing associated therewith
    • F15B15/08Characterised by the construction of the motor unit
    • F15B15/14Characterised by the construction of the motor unit of the straight-cylinder type
    • F15B15/1423Component parts; Constructional details
    • F15B15/1466Hollow piston sliding over a stationary rod inside the cylinder
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B15/00Fluid-actuated devices for displacing a member from one position to another; Gearing associated therewith
    • F15B15/20Other details, e.g. assembly with regulating devices
    • F15B15/22Other details, e.g. assembly with regulating devices for accelerating or decelerating the stroke
    • F15B15/226Other details, e.g. assembly with regulating devices for accelerating or decelerating the stroke having elastic elements, e.g. springs, rubber pads
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16FSPRINGS; SHOCK-ABSORBERS; MEANS FOR DAMPING VIBRATION
    • F16F9/00Springs, vibration-dampers, shock-absorbers, or similarly-constructed movement-dampers using a fluid or the equivalent as damping medium
    • F16F9/32Details
    • F16F9/50Special means providing automatic damping adjustment, i.e. self-adjustment of damping by particular sliding movements of a valve element, other than flexions or displacement of valve discs; Special means providing self-adjustment of spring characteristics
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16JPISTONS; CYLINDERS; SEALINGS
    • F16J10/00Engine or like cylinders; Features of hollow, e.g. cylindrical, bodies in general
    • F16J10/02Cylinders designed to receive moving pistons or plungers

Definitions

  • the present invention concerns a device for damping of a piston being connected to a piston rod and being moveable to and fro inside a cylinder housing of a cylinder, including a damping recess being associated with the piston and a damping protrusion for co-operation with the damping recess and for attachment to a first cylinder end wall of the cylinder housing, wherein the damping protrusion, with a aid of a first sealing device, is arranged to establish a damping chamber in co-operation with a contact portion inside the damping recess for damping the movement of the piston inside the cylinder housing in the region of a first position of the piston.
  • the invention also concerns a hydraulic cylinder and a shock absorber including such a device as well as a use of such a device .
  • the restriction can be comprised of the very slot between the damping protrusion and the damping recess, a throttle arranged in a particularly arranged throttle channel or a combination thereof.
  • the aim of the present invention is to provide a further developed device for damping allowing effective damping at the same time as possibility of a compact construction.
  • the damping recess is constructed to extend through the piston and into the piston rod and is arranged to receive the damping protrusion in said first position, and - that the damping protrusion in the area of its free end is provided with a second sealing device in order to establish a damping chamber in co-operation with said contact portion also in a second position of the piston.
  • an increased stroke length of a hydraulic device such as a hydraulic cylinder or a shock absorber can be achieved using the same axial dimensions as in a conventional hydraulic device such as a hydraulic cylinder or a shock absorber.
  • each sealing device includes a conical portion that is widening in the direction of the respective adjacent end of the damping protrusion, whereupon a flexible sealing ring having conical inside is axially moveable, it is achieved that the damping will be self regulating.
  • Self regulation is based on the fact that the damping protrusion is provided with a conical portion which is widening in the direction of an adjacent cylinder end wall and thus is diminishing inwards, towards the centre of the cylinder, and whereupon a flexible damping ring with a conical inside is axially moveably arranged.
  • the damping ring will be pressed more or less upwards on the conical portion and consequently will expand more or less radially.
  • a damping slot between the periphery of the damping ring and the inside of the damping recess will vary depending on the pressure difference between the sides of the damping ring, which results in that the damping will be dependent on the speed of the piston. The higher the speed of the piston, the greater the resulting damping will become.
  • damping properties can be adapted to the prevailing conditions of the application in question by dimensioning the lengths, diameters, cone angles of the parts involved as well as the hardness and the flexible properties of the sealing rings.
  • the contact portion is in the form of a portion having reduced inner diameter compared to the remaining parts of the damping recess. It is preferred that the contact portion is comprised of an inner portion of a sleeve inserted inside the damping recess.
  • first and the second sealing devices prefferably have different characteristics in order to obtain different damping properties for the movements in the two movement directions of the piston. This can be suitable if for example different forces are expected in the different directions .
  • the inventive device is advantageously arranged in a hydraulic cylinder which exhibits inlet/outlet for hydraulic liquid, and which is normally arranged to perform work in connection with a linear movement controlled by supply of said hydraulic liquid.
  • the device is then applied firstly to provide end position damping of the piston movement in the both directions.
  • the first direction of the piston is then a first end position and the second position of the piston is then a second end position.
  • the inventive device is advantageously also applied in respect of a shock absorber, which contains a hydraulic liquid and is normally arranged to damp a movement between two machine parts controlled by the limitation of flow of said hydraulic liquid.
  • the device is then applicable in order to provide extra damping in different length positions or end positions of the piston.
  • Figs. 1 and 2 show axial sections through a hydraulic cylinder according to the invention with arrangements for end position damping in both directions in a first and in a second position of the piston.
  • Figs. 1 and 2 illustrate a preferred variant of an inventive hydraulic cylinder 1 with a piston 3 being end position damped in both direction, being connected to a piston rod 4 and being moveable to and fro inside a cylinder housing 2.
  • a first cylinder end wall indicated with 5 exhibits a feed channel 7 for hydraulic liquid.
  • a second cylinder end wall is indicated with 6. From the first cylinder 1 end wall 5 extends a damping protrusion 9 in principle in form of a central rod, which extends from a proximal end 10 through essentially the entire axial length of the hydraulic cylinder to a distal free end 11.
  • the damping protrusion is a unit including a central screw, which co-operates with a screw hole in the first cylinder end wall.
  • the piston is as conventional provided with usual seals for the co-operation with the cylinder housing.
  • a damping recess 8 is arranged inside the piston and the piston rod. Altogether, a hollow inside these components form a recess, comprising said damping recess 8, arranged to receive the damping protrusion in a first end position of the piston, which is shown in Fig. 1.
  • the damping protrusion 9 exhibits a first sealing device 12 for cooperation with a contact portion 17 in the form of a portion such as a sleeve with reduced inner diameter compared to the remaining portion of the damping recess, in order to establish a damping chamber in the region of a first end position of the piston 3. This position is shown in Fig. 1.
  • protrusion 9 exhibit a second sealing device 15 for cooperation with said contact portion 17, in order to establish a damping chamber also in a region of a second end position of the piston 3, opposite to the first cylinder end wall 5. This position is shown in Fig. 2.
  • Each sealing device 12, 15 includes a conical portion 14 and 16, respectively, that is widening in the direction of the respective adjacent end 10, 11 of the damping recess 9. Onto these portions there is a respective flexible sealing ring 13 and 18, having a conical inside, axially moveable.
  • the damping will hereby be self regulating for reasons explained above.
  • the invention can be modified within the scoop of the following claims. It is for example possible to construct both damping devices with different characteristics in order to obtain different damping properties for the movements in the two movement directions of the piston.
  • the hydraulic cylinder can be constructed differently from what is shown on the drawings, as can the construction of the piston and the piston rod as well as of the contact
  • the damping protrusion can be made differently and be fastened to the first cylinder end wall with alternative means from what is shown. It is further possible to adapt the length of the parts of the damping protrusion in order to ensure that damping is obtained at desired positions of the piston.
  • An inventive shock absorber includes a hydraulic liquid, and is normally arranged to damp a movement between two
  • the device according to the invention is hereby applicable in order to provide extra damping in
  • the piston can in this case exhibit normal sealing devices vis-avis the cylinder housing and the first and second sealing devices can be arranged for damping in other positions than end positions in order to adapt the shock absorber to

Landscapes

  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Fluid-Damping Devices (AREA)

Abstract

A device for damping of a piston (3) being connected to a piston rod (4) and being moveable to and fro inside a cylinder housing (2) of a cylinder, including a damping recess (8) being associated with the piston and a damping protrusion for co-operation with the damping recess and for attachment to a first cylinder end wall (5) of the cylinder housing, wherein the damping protrusion, with a aid of a first sealing device (12), is arranged to establish a damping chamber in co¬ operation with a contact portion (17) inside the damping recess for damping the movement of the piston (3) inside the cylinder housing. The damping protrusion (8) extends axially over essentially the entire length of the cylinder housing with a proximal end (10) attached to the first cylinder end wall (5) and with a distal, free end (11) in a region inside the hydraulic cylinder opposite to the first cylinder end wall (5). The damping recess (8) extends through the piston and into the piston rod (4) and is arranged to receive the damping protrusion (9) in said first position. The damping protrusion (9) in the area of its free end (11) is provided with a second sealing device (15) in order to establish a damping chamber in co-operation with said contact portion (17) also in a second position of the piston (3). The invention also relates to hydraulic cylinder, a shock absorber and use in a hydraulic cylinder and a shock absorber.

Description

DEVICE FOR DAMPING OF A PISTON INSIDE A CYLINDER HOUSING
FIELD OF THE INVENTION
The present invention concerns a device for damping of a piston being connected to a piston rod and being moveable to and fro inside a cylinder housing of a cylinder, including a damping recess being associated with the piston and a damping protrusion for co-operation with the damping recess and for attachment to a first cylinder end wall of the cylinder housing, wherein the damping protrusion, with a aid of a first sealing device, is arranged to establish a damping chamber in co-operation with a contact portion inside the damping recess for damping the movement of the piston inside the cylinder housing in the region of a first position of the piston. The invention also concerns a hydraulic cylinder and a shock absorber including such a device as well as a use of such a device .
BACKGROUND OF THE INVENTION
Devices for damping are previously known in the form of arrangements for end position damping in hydraulic cylinders with a moveable piston inside a cylinder room. In an end position of the piston close to a cylinder end wall, a damping chamber is arranged to be established in that a damping protrusion on the one element (the piston or the cylinder end wall) will enter a damping recess in the other element.
Hereby a damping chamber is established which contains a certain amount of hydraulic liquid. During the final movement of the piston in the direction of an end position with
established damping chamber, at least a part of this liquid will now be forced to pass some form of restriction.
Hereby the kinetic energy of the piston and possible associated components will be absorbed by the hydraulic liquid and be transformed to heat in the liquid and adjacent
elements. The restriction can be comprised of the very slot between the damping protrusion and the damping recess, a throttle arranged in a particularly arranged throttle channel or a combination thereof.
For end position damping in both directions, arrangements are known which comprise damping recesses and damping
protrusions associated with both cylinder end walls of the hydraulic cylinder. On the piston rod side it is here arranged such that a damping protrusion is arranged surrounding the piston rod and that a corresponding damping recess is arranged adjacent to the piston rod opening of the cylinder end wall in question. Such a solution requires increased axial dimensions in order to give room for the damping devices.
AIM AND MOST IMPORTANT FEATURES OF THE INVENTION
The aim of the present invention is to provide a further developed device for damping allowing effective damping at the same time as possibility of a compact construction.
This aims are achieved in respect of a device of the kind indicated above in: - that the damping protrusion is
constructed to extend axially in an inside portion of the length of the cylinder housing with a proximal end to be attached to the first cylinder end wall and with a distal, free end in a region inside the hydraulic cylinder opposite to the first cylinder end wall, - that the damping recess is constructed to extend through the piston and into the piston rod and is arranged to receive the damping protrusion in said first position, and - that the damping protrusion in the area of its free end is provided with a second sealing device in order to establish a damping chamber in co-operation with said contact portion also in a second position of the piston. Hereby is achieved that the device can be produced axially very compact, since the components belonging to the damping arrangements as a whole are positional inside the hollow piston and the hollow piston rod of a hydraulic device such as a hydraulic cylinder or a shock absorber.
Hereby no elements have to extend axially from the piston or the cylinder end walls, elements that would unavoidably result in increased axial length of a hydraulic cylinder or a shock absorber wherein they would be inserted.
This is a great advantage since maintained stroke length of a hydraulic device such as a hydraulic cylinder or a shock absorber can be achieved with axially reduced dimensions.
Reversed, an increased stroke length of a hydraulic device such a hydraulic cylinder or a shock absorber can be achieved using the same axial dimensions as in a conventional hydraulic device such as a hydraulic cylinder or a shock absorber.
When, in a preferred aspect of the invention, each sealing device includes a conical portion that is widening in the direction of the respective adjacent end of the damping protrusion, whereupon a flexible sealing ring having conical inside is axially moveable, it is achieved that the damping will be self regulating. Self regulation is based on the fact that the damping protrusion is provided with a conical portion which is widening in the direction of an adjacent cylinder end wall and thus is diminishing inwards, towards the centre of the cylinder, and whereupon a flexible damping ring with a conical inside is axially moveably arranged.
Depending on the speed of the piston when the damping chamber is established, the damping ring will be pressed more or less upwards on the conical portion and consequently will expand more or less radially. Hereby a damping slot between the periphery of the damping ring and the inside of the damping recess will vary depending on the pressure difference between the sides of the damping ring, which results in that the damping will be dependent on the speed of the piston. The higher the speed of the piston, the greater the resulting damping will become.
It should be understood that damping properties can be adapted to the prevailing conditions of the application in question by dimensioning the lengths, diameters, cone angles of the parts involved as well as the hardness and the flexible properties of the sealing rings.
When the damping recess is a bore in the piston rod, manufacture is simplified and an economical and technically advantageous construction is ensured.
Suitably the contact portion is in the form of a portion having reduced inner diameter compared to the remaining parts of the damping recess. It is preferred that the contact portion is comprised of an inner portion of a sleeve inserted inside the damping recess.
It is possible to construct the first and the second sealing devices to have different characteristics in order to obtain different damping properties for the movements in the two movement directions of the piston. This can be suitable if for example different forces are expected in the different directions .
The inventive device is advantageously arranged in a hydraulic cylinder which exhibits inlet/outlet for hydraulic liquid, and which is normally arranged to perform work in connection with a linear movement controlled by supply of said hydraulic liquid. The device is then applied firstly to provide end position damping of the piston movement in the both directions. The first direction of the piston is then a first end position and the second position of the piston is then a second end position. The inventive device is advantageously also applied in respect of a shock absorber, which contains a hydraulic liquid and is normally arranged to damp a movement between two machine parts controlled by the limitation of flow of said hydraulic liquid. The device is then applicable in order to provide extra damping in different length positions or end positions of the piston.
BRIEF DESCRIPTION OF DRAWINGS
The invention will now be explained in more detail by way of embodiments and with reference to the drawing, whereon:
Figs. 1 and 2 show axial sections through a hydraulic cylinder according to the invention with arrangements for end position damping in both directions in a first and in a second position of the piston.
DESCRIPTION OF EMBODIMENT
Figs. 1 and 2 illustrate a preferred variant of an inventive hydraulic cylinder 1 with a piston 3 being end position damped in both direction, being connected to a piston rod 4 and being moveable to and fro inside a cylinder housing 2. A first cylinder end wall indicated with 5 exhibits a feed channel 7 for hydraulic liquid. A second cylinder end wall is indicated with 6. From the first cylinder 1 end wall 5 extends a damping protrusion 9 in principle in form of a central rod, which extends from a proximal end 10 through essentially the entire axial length of the hydraulic cylinder to a distal free end 11.
In the shown example, the damping protrusion is a unit including a central screw, which co-operates with a screw hole in the first cylinder end wall. Onto the screw there are arranged components having bores corresponding to the screw, components forming distance portions as well as parts of the sealing devices.
The piston is as conventional provided with usual seals for the co-operation with the cylinder housing.
A damping recess 8 is arranged inside the piston and the piston rod. Altogether, a hollow inside these components form a recess, comprising said damping recess 8, arranged to receive the damping protrusion in a first end position of the piston, which is shown in Fig. 1.
In the region of its proximal end 10, the damping protrusion 9 exhibits a first sealing device 12 for cooperation with a contact portion 17 in the form of a portion such as a sleeve with reduced inner diameter compared to the remaining portion of the damping recess, in order to establish a damping chamber in the region of a first end position of the piston 3. This position is shown in Fig. 1.
Also in the area of its free end 11, the damping
protrusion 9 exhibit a second sealing device 15 for cooperation with said contact portion 17, in order to establish a damping chamber also in a region of a second end position of the piston 3, opposite to the first cylinder end wall 5. This position is shown in Fig. 2.
Each sealing device 12, 15 includes a conical portion 14 and 16, respectively, that is widening in the direction of the respective adjacent end 10, 11 of the damping recess 9. Onto these portions there is a respective flexible sealing ring 13 and 18, having a conical inside, axially moveable. The damping will hereby be self regulating for reasons explained above.
The invention can be modified within the scoop of the following claims. It is for example possible to construct both damping devices with different characteristics in order to obtain different damping properties for the movements in the two movement directions of the piston. The hydraulic cylinder can be constructed differently from what is shown on the drawings, as can the construction of the piston and the piston rod as well as of the contact
portion. The damping protrusion can be made differently and be fastened to the first cylinder end wall with alternative means from what is shown. It is further possible to adapt the length of the parts of the damping protrusion in order to ensure that damping is obtained at desired positions of the piston.
The invention has been described in the above embodiments to the background of a hydraulic cylinder, but it is equally applicable in respect of a shock absorber.
An inventive shock absorber includes a hydraulic liquid, and is normally arranged to damp a movement between two
machine parts controlled by the limitation of flow of said hydraulic liquid. The device according to the invention is hereby applicable in order to provide extra damping in
different length positions or end positions of the piston. The piston can in this case exhibit normal sealing devices vis-avis the cylinder housing and the first and second sealing devices can be arranged for damping in other positions than end positions in order to adapt the shock absorber to
requirements of the applications in question.

Claims

8 2 7 -06- 2012 C L A I M S
1. Device for damping of a piston (3) being connected to a piston rod (4) and being moveable to and fro inside a cylinder housing (2) of a cylinder, including a damping recess (8) being associated with the piston and a damping protrusion for co-operation with the damping recess and for attachment to a first cylinder end wall (5) of the cylinder housing, wherein the damping protrusion, with a aid of a first sealing device (12), is arranged to establish a damping chamber in cooperation with a contact portion (17) inside the damping recess for damping the movement of the piston (3) inside the cylinder housing in the region of a first position of the piston (3 ) ,
c h a r a c t e r i z e d in
- that the damping protrusion (8) is constructed to extend axially in an inside portion of the length of the cylinder housing with a proximal end (10) to be attached to the first cylinder end wall (5) and with a distal, free end (11) in a region inside the hydraulic cylinder opposite to the first cylinder end wall (5) ,
- that the damping recess (8) is constructed to extend through the piston and into the piston rod (4) and is arranged to receive the damping protrusion (9) in said first position, and - that the damping protrusion (9) in the area of its free end (11) is provided with a second sealing device (15) in order to establish a damping chamber in co-operation with said contact portion (17) also in a second position of the piston (3) .
2. Device according to claim 1, c h a r a c t e r i z e d in that each sealing device (12,-15) includes a conical portion (14,-16) that is widening in the direction of the respective adjacent end of the damping protrusion (9) , whereupon a flexible sealing ring (13; 18) having conical inside is axially moveable .
3. Device according to claim 1 or 2 , c h a r a c t e r i z e d in that the damping recess (8) is a bore inside the piston rod .
4. Device according to claim 1, 2 or 3,
c h a r a c t e r i z e d in that the contact portion (17) is in the form of a portion having reduced inner diameter compared to the remaining parts of the damping recess .
5. Device according to any one of the previous claims, c h a r a c t e r i z e d in that the first and the second sealing devices (12; 15) have different characteristics in order to obtain different damping properties for the movements in the two movement directions of the piston (3) .
6. Hydraulic cylinder with a piston being moveable to and fro inside a cylinder housing between two cylinder end walls, the piston being connected to a piston rod, wherein the hydraulic cylinder includes a device according to any one of the claims 1 - 5.
7. Shock absorber with a piston being moveable to and fro inside a cylinder housing between two cylinder end walls, the piston being connected to a piston rod, wherein the shock absorber includes a device according to any one of the claims 1 - 5.
8. Use of a device according to any one of the claims 1 - 5, in any one from the group: a hydraulic cylinder, a shock absorber .
PCT/SE2012/050561 2011-06-17 2012-05-25 Device for damping of a piston inside a cylinder housing WO2012173550A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
EP12800071.8A EP2721307A4 (en) 2011-06-17 2012-05-25 Device for damping of a piston inside a cylinder housing

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
SE1100471A SE536053C2 (en) 2011-06-17 2011-06-17 Device for damping in a piston cylinder device
SE1100471-0 2011-06-17

Publications (1)

Publication Number Publication Date
WO2012173550A1 true WO2012173550A1 (en) 2012-12-20

Family

ID=47357827

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/SE2012/050561 WO2012173550A1 (en) 2011-06-17 2012-05-25 Device for damping of a piston inside a cylinder housing

Country Status (3)

Country Link
EP (1) EP2721307A4 (en)
SE (1) SE536053C2 (en)
WO (1) WO2012173550A1 (en)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103438049A (en) * 2013-08-30 2013-12-11 长治清华机械厂 Oil cylinder of drilling and exploring measuring device
WO2016127382A1 (en) * 2015-02-13 2016-08-18 National Oilwell Varco Petroleum Equipment (Shanghai) Co., Ltd. Reciprocating pump
CN108397440A (en) * 2018-04-11 2018-08-14 江阴市军炫智能装备有限公司 A kind of fast unit for medium-and-large-sized hydraulic pressure metal bits cuber
CN117536946A (en) * 2023-12-29 2024-02-09 浙江路得坦摩汽车部件股份有限公司 Damping linear change oil hydraulic cylinder with buffering function

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4352318A (en) * 1980-03-06 1982-10-05 Miller Fluid Power Corporation Expandable cushion plunger for piston and cylinder devices
CH677963A5 (en) * 1989-01-23 1991-07-15 Hydraulika Gmbh Hydraulic or pneumatic operating cylinder - has cylinder piston and piston rod, brake cylinder and brake bushing with throttles
US5224413A (en) * 1992-07-13 1993-07-06 Mosier Industries, Inc. Impact dampening means for power cylinders
US20020184997A1 (en) * 2001-06-08 2002-12-12 Festo Corporation Double acting cylinder with integral end position volume chambers

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR1361134A (en) * 1963-06-25 1964-05-15 Bbc Brown Boveri & Cie Air damped pneumatic control system
US3559776A (en) * 1969-06-17 1971-02-02 Gen Motors Corp Shock lockout and piston system
DE2755878A1 (en) * 1977-12-15 1979-06-21 Licentia Gmbh HYDRAULIC WORK CYLINDER WITH ADJUSTABLE DAMPING
DE3017403A1 (en) * 1980-05-07 1981-11-12 Stabilus Gmbh, 5400 Koblenz HYDROPNEUMATIC FEED CYLINDER
US6481335B2 (en) * 1999-12-23 2002-11-19 Mark Y. Shteynberg Hybrid actuator
ITTO20020504A1 (en) * 2002-06-14 2003-12-15 Vep Automation Srl ARM SWING DAMPING DEVICE OF A SWING LEVER TYPE HANDLING EQUIPMENT

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4352318A (en) * 1980-03-06 1982-10-05 Miller Fluid Power Corporation Expandable cushion plunger for piston and cylinder devices
CH677963A5 (en) * 1989-01-23 1991-07-15 Hydraulika Gmbh Hydraulic or pneumatic operating cylinder - has cylinder piston and piston rod, brake cylinder and brake bushing with throttles
US5224413A (en) * 1992-07-13 1993-07-06 Mosier Industries, Inc. Impact dampening means for power cylinders
US20020184997A1 (en) * 2001-06-08 2002-12-12 Festo Corporation Double acting cylinder with integral end position volume chambers

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See also references of EP2721307A4 *

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103438049A (en) * 2013-08-30 2013-12-11 长治清华机械厂 Oil cylinder of drilling and exploring measuring device
CN103438049B (en) * 2013-08-30 2016-05-04 长治清华机械厂 Probing analyzer oil cylinder
WO2016127382A1 (en) * 2015-02-13 2016-08-18 National Oilwell Varco Petroleum Equipment (Shanghai) Co., Ltd. Reciprocating pump
CN108397440A (en) * 2018-04-11 2018-08-14 江阴市军炫智能装备有限公司 A kind of fast unit for medium-and-large-sized hydraulic pressure metal bits cuber
CN117536946A (en) * 2023-12-29 2024-02-09 浙江路得坦摩汽车部件股份有限公司 Damping linear change oil hydraulic cylinder with buffering function
CN117536946B (en) * 2023-12-29 2024-04-30 浙江路得坦摩汽车部件股份有限公司 Damping linear change oil hydraulic cylinder with buffering function

Also Published As

Publication number Publication date
SE1100471A1 (en) 2012-12-18
SE536053C2 (en) 2013-04-16
EP2721307A4 (en) 2015-07-08
EP2721307A1 (en) 2014-04-23

Similar Documents

Publication Publication Date Title
KR102131400B1 (en) Hydraulic damper with a hydraulic compression stop assembly
KR101858196B1 (en) Hydraulic suspension damper with a hydro-mechanical stroke stop
EP2992158B1 (en) Improvements in damper assemblies
US10578185B2 (en) Shock absorber
US10174802B2 (en) Hydraulic damper with a hydraulic stop arrangement
EP2828546B1 (en) Hydraulic damper with adjustable rebound valve assembly
CN107850165B (en) Vibration damper for a motor vehicle
EP2807396B1 (en) Improvements in damper assemblies
EP2721307A1 (en) Device for damping of a piston inside a cylinder housing
CN104411997B (en) It is suitable to the damper of hinge
CN108006141A (en) A kind of hydraulic bjuffer
CN112483579A (en) Hydraulic damper with pull stop and push stop
CN108150578A (en) A kind of liquid condenser for becoming the damping of working clearance no maximum
CN106870499B (en) A kind of damping buffering valve
CN102410278A (en) Multistage single-action hydraulic cylinder and engineering machinery provided with same
JP2018150952A (en) Pressure shock absorber
CN108343696B (en) Vibration damper
CN105156558A (en) Self-adaptive magneto-rheological damper with single-rod variable cylinder body
CN104204550A (en) Hydraulic cylinder
CN102401068B (en) Orifice Valve
JP2016521832A (en) Installation of fluid flow hat for actuated valve
CN104452576B (en) Speed displacement two lock adjustable type viscous damper
CN208024754U (en) Minitype damper and its piston
KR20160076592A (en) Mr fluid damper
JP5346324B2 (en) Damping valve

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 12800071

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

REEP Request for entry into the european phase

Ref document number: 2012800071

Country of ref document: EP

WWE Wipo information: entry into national phase

Ref document number: 2012800071

Country of ref document: EP