GB2123922A - Hydraulic damper with adjustable flow path - Google Patents

Hydraulic damper with adjustable flow path Download PDF

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Publication number
GB2123922A
GB2123922A GB08316111A GB8316111A GB2123922A GB 2123922 A GB2123922 A GB 2123922A GB 08316111 A GB08316111 A GB 08316111A GB 8316111 A GB8316111 A GB 8316111A GB 2123922 A GB2123922 A GB 2123922A
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GB
United Kingdom
Prior art keywords
piston
cylinder
valve
passages
piston rod
Prior art date
Legal status (The legal status 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 status listed.)
Withdrawn
Application number
GB08316111A
Other versions
GB8316111D0 (en
Inventor
Akihiro Shimokura
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Tokico Ltd
Original Assignee
Tokico Ltd
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
Priority claimed from JP8896182U external-priority patent/JPS58191447U/en
Priority claimed from JP8896282U external-priority patent/JPS58191448U/en
Application filed by Tokico Ltd filed Critical Tokico Ltd
Publication of GB8316111D0 publication Critical patent/GB8316111D0/en
Publication of GB2123922A publication Critical patent/GB2123922A/en
Withdrawn legal-status Critical Current

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16F—SPRINGS; SHOCK-ABSORBERS; MEANS FOR DAMPING VIBRATION
    • F16F9/00—Springs, vibration-dampers, shock-absorbers, or similarly-constructed movement-dampers using a fluid or the equivalent as damping medium
    • F16F9/32—Details
    • F16F9/50—Special 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
    • F16F9/516—Special 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 resulting in the damping effects during contraction being different from the damping effects during extension, i.e. responsive to the direction of movement
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16F—SPRINGS; SHOCK-ABSORBERS; MEANS FOR DAMPING VIBRATION
    • F16F9/00—Springs, vibration-dampers, shock-absorbers, or similarly-constructed movement-dampers using a fluid or the equivalent as damping medium
    • F16F9/32—Details
    • F16F9/44—Means on or in the damper for manual or non-automatic adjustment; such means combined with temperature correction
    • F16F9/46—Means on or in the damper for manual or non-automatic adjustment; such means combined with temperature correction allowing control from a distance, i.e. location of means for control input being remote from site of valves, e.g. on damper external wall
    • F16F9/466—Throttling control, i.e. regulation of flow passage geometry
    • F16F9/467—Throttling control, i.e. regulation of flow passage geometry using rotary valves
    • F16F9/468—Throttling control, i.e. regulation of flow passage geometry using rotary valves controlling at least one bypass to main flow path

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  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Vehicle Body Suspensions (AREA)
  • Fluid-Damping Devices (AREA)

Abstract

A hydraulic damper comprises a cylinder 2 containing hydraulic liquid therein, a piston working 5 in the cylinder and partitioning the interior of the cylinder into two liquid chambers R1, R2, a hollow piston rod 4 connected to the piston, a passage formed in the piston rod for communicating the two liquid chambers and an adjusting valve member 21 for changing the effective passage area of the passage, the passage comprising two mutually independent passages L1, L2, and a check valve 26 being provided in one of the two passages for preventing liquid flow in one passage during either one of extension and contraction strokes. <IMAGE>

Description

SPECIFICATION Hydraulic damper This invention relates to a hydraulic damper of adjustable damping force type.
Recently, hydraulic dampers of adjustable damping force type have been utilized widely in automotive vehicles for improving the driving comfortableness by changing the damping force characteristics of the damper to match with the condition of the vehicle and of the road on which the vehicle is running. Namely, when the vehicle is running on a paved or smooth road the damping force is preferably decreased, and when the vehicle is running on a rough road, it is preferred to increase the damping force.
Various proposals have been made to adjust the damping force of hydraulic dampers from the outside. One of prior art hydraulic dampers of adjustable damping force type comprises a cylinder containing hydraulic liquid therein, a piston working in the cylinder and partitioning the interior of the cylinder into two liquid chambers, a hollow piston rod connected to the piston and extending out of the cylinder through one end thereof, a damping force generating mechanism mounted on the piston for generating damping force on at least one of extension and contraction strokes of the damper, a by-pass passage formed in the piston rod for communicating the two liquid chambers independently from the damping force generating mechanism, a valve member for adjusting the effective passage area of the by-pass passage, and an actuating rod connected to the valve member and extending through the piston rod. By operating the actuating rod from the outside, the liquid flow passing through the by-pass passage is adjusted and, thus, the damping force can easily be adjusted. However, the by-pass passage acts to adjust the damping force both in the extension and contraction strokes of the damper.
While, in usual hydraulic dampers used in the suspension system of the automotive vehicles, it has been determined that the damping force characteristics relative to the piston speed in the extension stroke of the damper are relatively large and relatively small in the contraction stroke of the damper.
When the adjustment of the damping force is effected by changing the effective passage area of a single by-pass passage, the change in the damping force in the extension stroke is larger than that in the contraction stroke and the ratio of the damping force between the extension and contraction strokes does not substantially change. However, in some cases, it is required to determine the range of adjustment in the damping force in the extension stroke as desired and also, to determine the range of adjustment in the contraction stroke as desired.
An object of the invention is to satisfy aforesaid requirements and, the invention relates to improvements in hydraulic damper of the kind including a cylinder containing hydraulic liquid therein, a piston working in the cylinder and partitioning the interior of the cylinder into two liquid chambers, a piston rod connected to the piston and extending out of the cylinder through one end thereof, a bore extending through the piston rod, a by-pass passage including a portion of the bore in the piston rod and a radial opening formed in the piston rod with one end thereof opening to one of the liquid chambers and the other end thereof opening to the other liquid chamber, an adjusting valve for adjusting the effective passage area of the passage, and an actuating rod connected to the adjusting valve and extending through the bore in the piston rod.According to the invention, the by-pass passage includes two branched passage portions, a check valve is provided in one of the branched passage portions to prevent the liquid flow in the one branched passage portion in either one of extension and contraction strokes, and the adjusting valve acts to adjust the liquid flow in the branched passages at least in the other of extension and contraction strokes.
According to the invention, the range of adjustment of the damping force in the extension stroke of the damper can be determined irrelevant to the range of adjustment of the damping force in the contraction stroke ofthe damper.
Further objects and advantages of the invention will hereinafter be explained in detail in conjunction with the drawings exemplifying some preferred embodiments of the invention, in which: Figure 1 is a longitudinal sectional view of a preferred embodiment of the invention, Figure 2 is an enlarged cross-sectional view taken along line 11- II in Figure 1; Figure 3 is an enlarged cross-sectional view taken along line Ill-Ill in Figure 1; Figure 4 is a diagram showing the relationship between damping force and piston speed of the damper of Figure 1; Figure 5 is an enlarged partial sectional view showing a modified form of the hydraulic damper; Figure 6 is a longitudinal sectional view of a second embodiment according to the invention, and Figure 7 is an enlarged view of the bottom valve in Figure 6.
Figure 1 shows a hydraulic damper according to a first embodiment of the invention, which comprises a dual tube type housing 1 consisting of an inner tube 2 constituting a cylinder according to the invention and an outer tube 3 coaxially surrounding the inner tube 2. A piston 5 is slidably received in the cylinder 2 and partitions the interior thereof into an upper liquid chamber R1 and a lower liquid chamber R2. A hollow piston rod 4 having a coaxial bore extending therethrough is connected to the piston 5 and extends through the upper chamber R1 and out of the housing 1 through the upper end of the housing 1. There is provided through the piston 5 a first passage 6 and a second passage 7 for communicating the two chambers R1 and R2. The passages 6 and 7 may consist respectively of two or more circumferentially spaced passages respectively.On the upper side of the piston 5, there is provided a first damping force generating valve 8 consisting of one or more annular resilient discs normally closing the first passage 6 and being adapted to open the passage 6 when the pressure in the lower chamber R2 exceeds the pressure in the upper chamber R1 by a predetermined amount. Similarly, a second damping force generating valve 10 is provided on the lower side of the piston 5 to normally close the second passage 7 and to open the passage 7 when the pressure in the upper chamber R1 exceeds the pressure in the lower chamber R2 by a predetermined amount.
The upper and lower chambers R, and R2 contain therein hydraulic liquid, and an annular space defined between the inner and outer tubes 2 and 3 contains gas G under pressure in the upper portion thereof and hydraulic liquid therein in the lower portion thereof. The annular space defines a reservoir chamber for compensating the change in the volume caused of the ingress or egress of the piston rod 4 into or out of the housing 1. The lower end of the reservoir chamber is connected to the lower end of the lower chamber R2 through a passage or opening 12. The upper end of the housing 1 is closed buy a cap 13, and a rod guide 14 is provided on the upper end of the cylinder 2 to guide the sliding movement of the piston rod 4.A seal member is disposed on the inner surface of the cap 13 to slidably engage with the piston rod 4 and to seal the interior of the housing 1 from the outside. A check valve is provided between the seal member and the rod guide 14to permit the fluid flow from the upper chamber R1 to the reservoir chamber through the clearance between the piston rod 4 and the rod guide 14 and to prevent the gas in the reservoir chamber from acting on the upper chamber R1. The lower end of the outer tube 3 is closed by a bottom cap 15, and a mounting ring 16 is secured to the bottom cap 15. Asuitable mounting device (not shown) is mounted or the upper end of the piston rod4.
The piston rod 4 has on the lower end a relatively large diameter counterbore to define a chamber R3 which is permanently communicated with the lower liquid chamber R2 A valve seat supporting member having an annular flange portion on the lower end of a tubular body portion is secured to the inner wall of the counterbore in the piston rod 4with the outer circumference of the annular flange being retained by suitable technique such as force4itting, C-ring or the like on the counterbore. An annular valve seat member 18 is mounted on the upper end of the valve seat supporting member 17. The valve seat supporting member has also a tubular body portion and a radially inwardly extending annular flange portion provided on the lower end of the tubular body portion.The flange portion of the valve seat member 18 defines a valve seat, and the tubular body portion has, as shown in Figure 2, four angularly spaced communicating passages 20. The tubular body portion of the valve seat supporting member 17 has also, as shown in Figure 3, four angularly spaced communicating passages 19.
A generally tubular valve member 21 having the inner diameter adapted to slidably engage with the outer circumference of the valve seat member 18 and the outer diameter adapted to slidably engage with the counterbore in the piston rod 14 acts to control the liquid flow between the chamber R3 and the upper liquid chamber R1. There are provided in the circumferential wall of the valve member 21 axially spaced and circumferentially extending cutouts 22 and 23 as shown in Figures 3 and 2.The cutouts 22 and 23 extend respectively by arcuate angle of about 90 degrees as shown, and there are also provided in the piston rod 4 axially spaced and circumferentially spaced three sets of radial openings 24, and 25" 242 and 252, and 243 and 253 having different cross-sectional area to cooperate respectively with cutouts 22 and 23 in the valve member 21.
The passage 19 in the valve seat supporting member 17, the cutout 22 in the valve member 21 and either of the radial openings 24,,242 and 243 constitute a first passage L1 connecting the chamber R3 with the liquid chamber R1, and the passage 20 in the valve seat member 18, the cutout 23 in the valve member 21 and either of the radial openings 25,,252 and 253 in the piston rod 4 constitute a second passage L2 connecting the chamber R3 with the liquid chamber R1 through the annular valve seat in the valve seat member 18. The valve seat in the valve seat member 18 is normally closed buy a check valve 26 which comprises a check valve member 28 and a biasing spring 27. The check valve 28 opens to permit the liquid flow from the chamber R3 to the chamber R1 but prevents the liquid flow in the opposite direction.
The effective passage area of the first and second passages L1 and L2 can be adjusted at three steps respectively by rotating the valve member 21. The valve member 21 is secured to an actuating rod 29 which extends through the central bore in the piston rod 4, and the upper end (not shown) of the actuating rod 29 projects out of the upper end of the piston rod 4 and is connected to a suitable actuating device (not shown).
In operation, when the piston rod 4 moves upward in Figure 1 in the extension stroke of the damper, the pressure in the upper chamber R1 increases as compared with the lower chamber r2, the check valve 26 closes and the first passage L, acts as a single by-pass passage. The damping force characteristics in the extension stroke are depicted by curves OP1 P1,, OP2P2', and OP3P3, in Figure 4. It will be understood that the rising up portions OP1, OP2 and OP3 in the curves are mainly determined by the effective passage area of the first passage L1 or the cross-sectional area (D1, D2 and D3) of the openings 24,i, 242 and 243 respectively.In the embodiment, the cross-sectional area of the opening 24, is the smallest and which defines the steepest line OP1 as shown in Figure 4. When the piston speed exceeds a predetermined speed, the second damping force generating valve 10 opens to generate a damping force such as shown in lines P1 P1 ', P2P2' and P3P3' in Figure 4. The difference between lines P1 P1 ', P2P2' and P3P3' is caused of the difference in the liquid flow passing through the orifice 24" 242 and 243.
In the contraction stroke of the damper, the piston rod 4 displaces downwards in the drawing and the liquid flows from the chamber P2 to the chamber P1.
The check valve 26 opens and the passages L1 and L2 constitute in parallel a by-pass passage. The damping force is depicted by either of lines Or101', Q2Q2' and 00303'. The rising up portions OQ1, 002 and 003 are determined respectively the effective passage area of the by-pass passage which are the sum of the cross-sectional area D1+d1, d2+d2 or d3+d3 of the openings 24, +25" 242+252 or 243+253.
When the piston speed increases the first damping force generating valve 8 opens and the damping force is determined by the liquid flow passing through the first communicating passage 6 and the by-pass passage L1+L2, and which is depicted by line Q,Q1', 0202' or03Q3,.
As heretofore described, the by-pass passage is formed, in the extension stroke of the damper, of a single passage L1 and, in the contraction stroke of the damper, of two passages L1 and L2, thus, it is possible to suitably determine the damping force in the extension stroke and in the contraction stroke, and to determine the ratio of the damping force between the extension stroke and the contraction stroke in the adjusted condition.According to the embodiment, the damping force depicted by line OQ3Q3' can be decreased sufficiently which enables to improve the driving comfortableness of an automobile running on a smooth road, while, the damping force depicted by line OQ1Q1' is maintained at relatively high, and the ratio between line OP3P3' and line 00303' is larger than the ratio between line OP1P1' and line OQ1Q1'.
Figure 5 shows another embodiment, wherein the valve seat member 18 and the valve member 21 in the first embodiment is substituted by a rotatable valve member 30. The valve member 30 has, in the circumferential wall, axially spaced and circumferentially extending cutouts 22 and 23, and is connected to the lower end of actuating rod 29. The valve member 30 is rotatably retained in the counterbore in the piston rod 4 by a retaining ring 31. Further, a plurality of axial openings 32 is formed in a radial wall provided in axially mid portion of the valve member 30. An annular plate-like check valve member 33 cooperates with the openings 32 and is biased toward the openings 32 to constitute the check valve 26. Shown at 36 in Figure 5 are seal rings provided on the upper and lower ends of the rotatable valve member 30, and at 37 is an O-ring for sealing the actuating rod 29.The operation of the second embodiment is similar to that of the first embodiment.
In the embodiments, the damping force in the contraction and extension strokes is adjusted at three steps, however, the number of adjusting steps may be determined as desired by changing the number of the openings 24 and 25 in the piston rod 4 and the configuration or the number of cutouts 22 and 23 in the valve member 21 or 30.
Figure 6 and Figure 7 show a third embodiment of the invention, which differs from the first embodiment in that a bottom valve 50 is provided in the lower end of the inner tube 2 and between the liquid chamber R2 and the lower end of the reservoir chamber. The construction of the piston 5 and the piston rod 4 and parts relating thereto are generally similar to the first embodiment with the same reference numerals being applied to corresponding parts, thus, detailed description therefor is omitted.
The bottom valve 50 comprises a generally tubular or inverted cup-shape upper cap 51 and an annular lower cap 52 mounted respectively on the lower end of the inner tube 2. An annular valve seat member 53 is disposed between the upper and lower caps 51 and 52 and is movable in the vertical direction. A vertical opening 54 acting as a fixed orifice of the bottom valve 50 extends through the central portion of the valve seat member 53, and a plurality of angularly spaced through holes 55 in the circumferential portion. An annular resilient valve member 56 consisting of a plurality of mutually overlapping discs is interposed between the valve seat member 53 and the lower cap 52 which normally covers the lower ends of the through holes 55. A biasing spring 57 is disposed between the upper cap 51 and the valve seat member 53 to bias downwards the valve seat member 53.
When the piston rod 4 moves upward in the extension stroke of the damper, the valve seat member 53 moves upward against the spring 57 due to the differential pressure between the reservoir chamber and the chamber R2, and a relatively large clearance is formed between the valve member 56 and the lower cap 52 so that a volume of liquid corresponding to the volume of the piston rod 4 egressing out of the upper chamber R1 is introduced from the reservoir chamber to the lower chamber r2 at a low resistance, as shown in Figure 6. At this condition, the holes 55 are closed.
The operation and the function of the by-pass passages L1 and L2 are similar to the first embodiment and, at that condition, the check valve 26 is closed. Thus, the by-pass passage L, defines the rising up portion OP1, OP2 or OP3 in the damping force characteristics. The disc valve 10 provided on the piston 5 acts to define the portion P,P,', P2P2' or P3P3' in the damping force characteristics as depicted in Figure 4.
When the piston rod 4 moves downward in the contraction stroke of the damper, the valve member 56 is clamped between the valve seat member 53 and the lower cap 52. When the piston speed is low, the valve member 56 closes the passages 55 and the liquid in the chamber R2 flows into the reservoir chamber only through the fixed orifice 54. Thereafter, in response to the increase in the piston speed, the valve member 56 is deflected as shown in Figure 7, the liquid corresponding to the volume of the piston rod ingressing into the cylinder 2 flows into the reservoir chamber through the passages 55 with a damping force being generated.
The operation and function of the by-pass passage L1 and L2 at that condition are similar to the first embodiment. The check valve 26 opens and the passage L1 and L2 cooperate to define the rising up portion OQ1, 002 or OQ3 in the damping force characteristics shown in Figure 4. The disc valve 8 provided on the piston 5 cooperate with the bottom valve 50 to define the portion Oi Oi', Q2Q2 or 0303' in Figure 4.
In the embodiments, the cross-section area or the diameter of the openings 24" 242,243, 2Si, 252 and 253 are defined as d1, d2, d3, D" D2 and D3 respectively, and it is assumed that d1 < d2 < d3, and D1 < D2 < D3. Further, by rotating the rotatable valve member 21, each pair of the smallest, the intermediate or the largest openings open simultaneously, thus, as shown in Figure 4, the rising up portions O0i, OQ2 and OQ3 in the contraction stroke are defined respectively by by-pass passages having effective passage areas of D1+d1, D2+d2 and D3+d3 as depicted in Figure 4.
It has been described that, in the contraction stroke of the damper, the damping force generating valve 8 on the piston 5 and the bottom valve 50 cooperate to define the portions Oil1', 0202' and 0303' in Figure 4, however, the characteristics of the valves 8 and 50 are preferably determined such that portions Q,Q,' and 0202' are mainly determined by the valve 8 and the portions 0303' is mainly determined that the bottom valve 50.It will be understood that the bottom valve 50 enables to sufficiently decrease the damping force defined by the portion 0303' as compared with the portion Q,Q,' or Q2Q2'. Thus, the ratio in the damping force between the extension and contraction strokes can further be increased at the maximum by-pass passage area condition as compared with the minimum by-pass passage area condition by providing the bottom valve 50.
In the embodiments, the damping force both in the extension and contraction strokes are adjusted at three steps respectively, but, the adjusting steps may be determined as desired by changing the number and arrangement of the opening 24 and 25 in the piston rod 4 and the configuration and the arrangement of cutouts 22 and 23 in the rotatable valve members 21.
As described heretofore, according to the invention, the damping force of the hydraulic damper can be adjusted at a desired wide range and the relationship between the damping force in the extension and contraction strokes of the damper can also be changed at a wide range. Thus, in applying the hydraulic damper in the suspension system of an automatic vehicle, the driving comfortableness in various operating conditions of the vehicle can further be improved.
Although the embodiments described relate to dual tube type hydraulic dampers, the invention can also be applied to single tube type hydraulic dam pers.

Claims (7)

1. A hydraulic damper comprising a cylinder containing hydraulic liquid therein, a piston working in the cylinder and partitioning the interior of the cylinder into two liquid chambers, a hollow piston rod connected to the piston and extending out of the cylinder through one end thereof, an internal cham ber formed in the piston rod to directly communicate with one of said two liquid chambers, two indepen dent passages formed in the piston rod to communicate respectively said internal chamber with the other of said two liquid chambers, a check valve provided in one of said passages, and an adjusting valve for adjusting the effective passage area of said two passages.
2. A hydraulic damper according to claim 1 wherein said check valve opens in the contraction stroke of the damper and closes in the extension stroke of the damper.
3. A hydraulic damper according to cliam 1 wherein a damping force generating valve mechanism is mounted on the piston and said passages act as by-pass passages of the valve mechanism.
4. A hydraulic damper according to claim 1 wherein said passages in the piston rod comprise respectively of a plurality of openings having different cross-sectional area and being selectively opened or closed by said adjusting valve.
5. A hydraulic damper according to claim 3 wherein said valve mechanism comprises disc valves cooperating with respective side surfaces of the piston to open when the piston moves in respective directions at respective predetermined high speed.
6. A hydraulic damper according to claim 1 wherein said cylinder is surrounded by a coaxial outer tube which defines between the cylinder an annular reservoir chamber containing therein gas and hydraulic liquid, and a bottom valve is provided between the lower end of the annular reservoir chamber and said one liquid chamber for generating a damping force in the contraction stroke of the damper.
7. A hydraulic damper substantially as hereinbefore described with reference to, and as illustrated in, Figures 1 to 4; or Figures 1 to 4 as modified by FigureS; or Figures 6 and 7 of the accompanying drawings.
GB08316111A 1982-06-15 1983-06-13 Hydraulic damper with adjustable flow path Withdrawn GB2123922A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP8896182U JPS58191447U (en) 1982-06-15 1982-06-15 Damping force adjustable hydraulic shock absorber
JP8896282U JPS58191448U (en) 1982-06-15 1982-06-15 Damping force adjustable hydraulic shock absorber

Publications (2)

Publication Number Publication Date
GB8316111D0 GB8316111D0 (en) 1983-07-20
GB2123922A true GB2123922A (en) 1984-02-08

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Family Applications (1)

Application Number Title Priority Date Filing Date
GB08316111A Withdrawn GB2123922A (en) 1982-06-15 1983-06-13 Hydraulic damper with adjustable flow path

Country Status (2)

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DE (1) DE3321680A1 (en)
GB (1) GB2123922A (en)

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GB2146734A (en) * 1983-09-20 1985-04-24 Tokico Ltd Hydraulic damper of adjustable damping force type
GB2147685A (en) * 1983-09-29 1985-05-15 Pipe Supports Ltd Damper with adjustable flow path
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CN105650055A (en) * 2016-03-31 2016-06-08 江阴市洪腾机械有限公司 Dual-piston-rod hydraulic cylinder
US9399383B2 (en) 2013-02-28 2016-07-26 Tenneco Automotive Operating Company Inc. Damper with integrated electronics
US9404551B2 (en) 2013-03-15 2016-08-02 Tenneco Automotive Operating Company Inc. Rod guide assembly with multi-piece valve assembly
CN106678246A (en) * 2017-03-01 2017-05-17 长春孔辉汽车科技股份有限公司 Adjustable damping absorber
US9879746B2 (en) 2013-03-15 2018-01-30 Tenneco Automotive Operating Company Inc. Rod guide system and method with multiple solenoid valve cartridges and multiple pressure regulated valve assemblies
US9879748B2 (en) 2013-03-15 2018-01-30 Tenneco Automotive Operating Company Inc. Two position valve with face seal and pressure relief port
US9884533B2 (en) 2013-02-28 2018-02-06 Tenneco Automotive Operating Company Inc. Autonomous control damper
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US10479160B2 (en) 2017-06-06 2019-11-19 Tenneco Automotive Operating Company Inc. Damper with printed circuit board carrier
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US4800994A (en) * 1983-09-20 1989-01-31 Tokico Ltd. Hydraulic damper of adjustable damping force type
GB2146734A (en) * 1983-09-20 1985-04-24 Tokico Ltd Hydraulic damper of adjustable damping force type
GB2147685A (en) * 1983-09-29 1985-05-15 Pipe Supports Ltd Damper with adjustable flow path
EP0179818A1 (en) * 1984-04-24 1986-05-07 Comdox No 70 Pty Ltd. Linear motion resistance cell
EP0179818A4 (en) * 1984-04-24 1987-09-21 Comdox Pty Ltd Linear motion resistance cell.
US4645044A (en) * 1984-06-20 1987-02-24 Tokico Ltd. Hydraulic damper of adjustable damping force type
GB2180320A (en) * 1985-09-11 1987-03-25 Fichtel & Sachs Ag Vibration damper with variable damping force
GB2180320B (en) * 1985-09-11 1989-09-06 Fichtel & Sachs Ag Vibration damper with variable damping force
US5044474A (en) * 1985-11-05 1991-09-03 Koni B.V. Electrically adjustable shock absorber
US4819771A (en) * 1986-02-15 1989-04-11 Daimler-Benz Ag Vibration damper for vehicles
US4765446A (en) * 1986-02-20 1988-08-23 Tokico Ltd. Hydraulic damper of adjustable damping force type
GB2207977A (en) * 1987-08-03 1989-02-15 Plastica & Met Ind Piston for shock absorbers
GB2207977B (en) * 1987-08-03 1992-01-22 Plastica & Met Ind Piston for shock absorbers
FR2621663A1 (en) * 1987-10-09 1989-04-14 Tokico Ltd Hydraulic damper of the adjustable damping force type
GB2265201A (en) * 1989-07-10 1993-09-22 Atsugi Unisia Corp Shock absorber
GB2265201B (en) * 1989-07-10 1994-01-05 Atsugi Unisia Corp Shock absorber
GB2236574A (en) * 1989-09-20 1991-04-10 Atsugi Unisia Corp Variable damping force shock absorber
US5193655A (en) * 1989-09-20 1993-03-16 Atsugia Unisia Corp. Variable damping force shock absorber with feature of linear and wide range damping force variation depending upon piston stroke speed
GB2236574B (en) * 1989-09-20 1993-05-12 Atsugi Unisia Corp Improvements in and relating to shock absorbers
WO1998039578A1 (en) * 1997-03-05 1998-09-11 Lord Corporation Two-way magnetorheological fluid valve assembly and devices utilizing same
US6095486A (en) * 1997-03-05 2000-08-01 Lord Corporation Two-way magnetorheological fluid valve assembly and devices utilizing same
US6158470A (en) * 1997-03-05 2000-12-12 Lord Corporation Two-way magnetorheological fluid valve assembly and devices utilizing same
US6659239B2 (en) * 2001-09-10 2003-12-09 Meritor Heavy Vehicle Technology, Llc Shock absorber through the rod damping adjustment
US7347307B2 (en) 2003-01-31 2008-03-25 Arvin Technologies Integrated damping adjustment valve
WO2004067990A1 (en) * 2003-01-31 2004-08-12 Arvin Technologies Integrated damping adjustment valve
ITFI20080178A1 (en) * 2008-09-17 2010-03-18 David Ciolini HYDRAULIC DAMPER
EP2166250A1 (en) * 2008-09-17 2010-03-24 Stefano Quirini Oleodynamic damper
US8616351B2 (en) 2009-10-06 2013-12-31 Tenneco Automotive Operating Company Inc. Damper with digital valve
US9810282B2 (en) 2009-10-06 2017-11-07 Tenneco Automotive Operating Company Inc. Damper with digital valve
US9150077B2 (en) 2009-10-06 2015-10-06 Tenneco Automotive Operating Company Inc. Damper with digital valve
US9695900B2 (en) 2009-10-06 2017-07-04 Tenneco Automotive Operating Company Inc. Damper with digital valve
US9109653B2 (en) 2010-05-20 2015-08-18 Suspa Gmbh Damper
CN102493969B (en) * 2011-12-19 2014-10-08 宁波千普机械制造有限公司 Hydraulic cylinder with double piston rods
CN102493969A (en) * 2011-12-19 2012-06-13 宁波千普机械制造有限公司 Hydraulic cylinder with double piston rods
US10000104B2 (en) 2013-02-28 2018-06-19 Tenneco Automotive Operating Company Inc. Damper with integrated electronics
US9217483B2 (en) 2013-02-28 2015-12-22 Tenneco Automotive Operating Company Inc. Valve switching controls for adjustable damper
US9925842B2 (en) 2013-02-28 2018-03-27 Tenneco Automotive Operating Company Inc. Valve switching controls for adjustable damper
US9399383B2 (en) 2013-02-28 2016-07-26 Tenneco Automotive Operating Company Inc. Damper with integrated electronics
US9884533B2 (en) 2013-02-28 2018-02-06 Tenneco Automotive Operating Company Inc. Autonomous control damper
US9802456B2 (en) 2013-02-28 2017-10-31 Tenneco Automotive Operating Company Inc. Damper with integrated electronics
US9404551B2 (en) 2013-03-15 2016-08-02 Tenneco Automotive Operating Company Inc. Rod guide assembly with multi-piece valve assembly
US9879746B2 (en) 2013-03-15 2018-01-30 Tenneco Automotive Operating Company Inc. Rod guide system and method with multiple solenoid valve cartridges and multiple pressure regulated valve assemblies
US9879748B2 (en) 2013-03-15 2018-01-30 Tenneco Automotive Operating Company Inc. Two position valve with face seal and pressure relief port
US9163691B2 (en) 2013-03-15 2015-10-20 Tenneco Automotive Operating Company Inc. Rod guide arrangement for electronically controlled valve applications
CN105650055A (en) * 2016-03-31 2016-06-08 江阴市洪腾机械有限公司 Dual-piston-rod hydraulic cylinder
CN106678246A (en) * 2017-03-01 2017-05-17 长春孔辉汽车科技股份有限公司 Adjustable damping absorber
US10479160B2 (en) 2017-06-06 2019-11-19 Tenneco Automotive Operating Company Inc. Damper with printed circuit board carrier
US10588233B2 (en) 2017-06-06 2020-03-10 Tenneco Automotive Operating Company Inc. Damper with printed circuit board carrier
ES2696800A1 (en) * 2017-07-17 2019-01-17 Gimeno Manuel Carcare Shock absorber cylinder. (Machine-translation by Google Translate, not legally binding)

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Publication number Publication date
DE3321680A1 (en) 1984-01-19
DE3321680C2 (en) 1991-08-01
GB8316111D0 (en) 1983-07-20

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