US20050263362A1 - Structure of piston for hydraulic shock absorber - Google Patents

Structure of piston for hydraulic shock absorber Download PDF

Info

Publication number
US20050263362A1
US20050263362A1 US11/133,458 US13345805A US2005263362A1 US 20050263362 A1 US20050263362 A1 US 20050263362A1 US 13345805 A US13345805 A US 13345805A US 2005263362 A1 US2005263362 A1 US 2005263362A1
Authority
US
United States
Prior art keywords
piston
piston rod
insert axis
axis portion
shock absorber
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.)
Abandoned
Application number
US11/133,458
Other languages
English (en)
Inventor
Akihisa Oota
Atsushi Noritake
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.)
KYB Corp
Original Assignee
Kayaba Industry Co 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
Application filed by Kayaba Industry Co Ltd filed Critical Kayaba Industry Co Ltd
Assigned to KAYABA INDUSTRY CO., LTD. reassignment KAYABA INDUSTRY CO., LTD. ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: NORITAKE, ATSUSHI, OOTA, AKIHISA
Publication of US20050263362A1 publication Critical patent/US20050263362A1/en
Abandoned legal-status Critical Current

Links

Images

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
    • F16F9/3207—Constructional features
    • F16F9/3228—Constructional features of connections between pistons and piston rods

Definitions

  • the present invention relates to a hydraulic shock absorber used for a suspension in an automobile or the like, and in particular, to a structure of a piston therefor.
  • a compression-side valve stopper 41 , a compression-side washer 42 , a compression-side damping valve 43 , a piston 44 , an expansion-side damping valve 45 , an expansion-side washer 46 , and an expansion-side valve stopper 47 are sequentially inserted and stacked to form a piston assembly body 48 in a temporary assembling state, which is transported to an assembling process to a piston rod 49 .
  • the present invention from a viewpoint of the foregoing problems, has an object of providing a structure of a piston for a hydraulic shock absorber, which can easily incorporate a piston to a piston rod, provide an easy assembling job, and reduce assembling costs.
  • the present invention comprises a hydraulic shock absorber provided with a cylinder, a piston sliding in the cylinder, and a piston rod to a top end of which the piston is connected.
  • the hydraulic shock absorber comprises a piston rod insert axis portion formed separately from the piston rod, a damping valve inserted and fixed in the piston rod insert axis portion together with the piston, and a combination member combining the piston rod insert axis portion with the top end of the piston rod.
  • FIG. 1 is a cross sectional view showing a substantial part of a piston assembly structure for a hydraulic shock absorber in a preferred embodiment of the present invention
  • FIG. 2 is a cross sectional view of a substantial part showing an assembling method of a piston in FIG. 1 ;
  • FIG. 3 is a cross sectional view of a substantial part showing a different preferred embodiment from the preferred embodiment in FIG. 1 ;
  • FIG. 4 is a cross sectional view of a substantial part showing a further preferred embodiment from the preferred embodiment in FIG. 1 ;
  • FIG. 5 is a cross sectional view of a substantial part showing a furthermore preferred embodiment from the preferred embodiment in FIG. 1 ;
  • FIG. 6 is a cross sectional view of a substantial part showing a furthermore different preferred embodiment from the preferred embodiment in FIG. 1 ;
  • FIG. 7 shows a conventional example and is a cross sectional view of a substantial part showing an assembling state of a piston unit
  • FIG. 8 shows the same conventional example and is a cross sectional view of a substantial part showing a state where the piston in FIG. 7 is incorporated in the piston rod.
  • a piston rod 2 connected to a piston 4 is located in a cylinder 1 .
  • a piston rod insert axis portion 3 is provided in a top end of the piston rod 2 , and the piston 4 is inserted in the piston rod insert axis portion 3 .
  • the piston 4 is bolted together with an expansion-side damping valve 6 and a compression-side damping valve 7 each provided on each face of the piston 4 by a nut 8 .
  • a screw bore 11 having a female screw on an inner peripheral surface is formed in an axis center of the top end of the piston rod 2 and a screw shaft 12 having a male screw threaded into the female screw is formed in the piston rod insert axis portion 3 formed separately from the piston rod 2 .
  • Threading the screw shaft 12 of the piston rod insert axis portion 3 into the screw hole 11 allows the piston rod insert axis portion 3 to be mounted and fixed coaxially to the top end of the piston rod 2 .
  • An engagement member 14 having a diameter larger than that of the screw shaft 12 is formed integrally with the piston rod insert axis portion 3 in the half thereof.
  • a pair of flat faces 14 a are formed in part of an outer peripheral surface of the engagement member 14 .
  • a screw portion 23 having a male screw is provided in the top end of the piston rod insert axis portion 3 to screw the piston nut 8 therein to be described later.
  • a mounting bore 5 is provided in the center of the piston 4 so as to go through the piston 4 , which is inserted through the mounting bore 5 into the piston rod insert axis portion 3 .
  • An expansion-side port 15 and a compression-side port 16 are formed in the piston 4 .
  • the compression-side damping valve 7 composed of a plurality of leaf valves opening/closing the compression-side port 16 is inserted in the piston rod insert axis portion 3 at a back side (refer to an upper face in FIG. 1 ) of the piston 4 , and a washer 18 and a valve stopper 19 are inserted similarly therein and arranged on the upper face of the compression-side damping valve 7 .
  • the expansion-side damping valve 6 composed of a plurality of leaf valves opening/closing the expansion-side port 15 is inserted in the piston rod insert axis portion 3 at a front side (refer to a lower face in FIG. 1 ) of the piston 4 , and further, a washer 22 is inserted therein.
  • Threading the piston nut 8 into the screw portion 23 allows the compression-side valve stopper 19 , the washer 18 , the compression-side damping valve 7 , the piston 4 , the expansion-side damping valve 6 , and the washer 22 to be clamped and fixed between the engagement member 14 and the piston nut 8 .
  • each of the compression-side and the expansion-side damping valve 6 and 7 is supported radially at an inner peripheral portion thereof between the engagement member 14 and the piston nut 8 , and is flexible and deformable freely at an outer peripheral portion thereof.
  • a clamp bore 24 for inserting a hexagonal head bolt wrench is provided in the top end of the piston rod insert axis portion 3 , and insert and rotation of the hexagonal head bolt wrench in the clamp bore 24 causes the piston rod insert axis portion 3 to be screwed into the screw bore 11 of the piston rod 2 .
  • a piston structure unit configured as above will be assembled as below.
  • a tool 27 is prepared for temporarily assembling the piston structure unit.
  • the tool 27 is provided with a concave portion 25 in which the screw shaft 12 of the piston rod insert axis portion 3 is inserted with a clearance between the screw shaft 12 and the concave portion 25 , and an engagement portion 26 in which the flat portion 14 a of the engagement member 14 is inserted and engaged.
  • the piston rod insert axis portion 3 is inserted and supported in the opposite directions to the upper and lower directions in FIG. 1 .
  • the engagement member 14 of the piston rod insert axis portion 3 is unrotatably fixed to the engagement portion 26 of the tool 27 , and the compression-side valve stopper 19 , the washer 18 , a plurality of the compression-side damping valves 7 , the piston 4 , a plurality of the expansion-side damping valves 6 , and the washer 22 are sequentially stacked and inserted.
  • the piston assembly body 28 as formed in such a way is transported to an assembling process to the piston rod 2 .
  • the compression-side valve stopper 19 , the washer 18 , a plurality of the compression-side damping valves 7 , the piston 4 , a plurality of the expansion-side damping valves 6 , and the washer 22 are sequentially stacked and inserted in the piston rod insert axis portion 3 formed separately from the piston rod 2 , which are clamped and fixed by the piston nut 8 , thereby completing the piston assembly body 0 . 28 beforehand. Only threading the piston assembly body 28 into the screw bore 11 of the piston rod 2 causes the piston 4 to be incorporated to the piston rod 2 .
  • a thin, cylindrical, and expansion regulation member 30 may be interposed between the engagement portion 14 and the piston rod 2 .
  • a bottom portion 30 a of the expansion regulation member 30 is placed and fixed between the top end of the piston rod 2 and the engagement member 14 of the piston rod insert axis portion 3 .
  • the expansion regulation member 30 is brought into contact with an inner periphery of an top end of the cylinder 1 at the state where the piston rod 2 is expanded at the maximum, thereby blocking the further expansion of the piston rod 2 .
  • an alternative to the engagement member 14 in the above-described preferred embodiment is a movable engagement member 31 having a nut structure formed separately from the piston rod insert axis portion 3 , and the piston rod insert axis portion 3 is formed in a bar shape on an entire outer periphery of which a male screw portion 32 is formed.
  • a cylindrical collar 33 is inserted into an inner periphery of a mounting bore 5 of the piston 4 to seal the outer peripheral surface of the male screw portion 32 , thereby preventing leakage of the operating oil.
  • the engagement member 31 in FIG. 4 is not used.
  • the piston nut 8 is screwed into the piston rod insert axis portion 3 formed in a bar shape. In this state, the piston nut 8 is placed on the tool to be positioned in a lower side of the piston rod insert axis portion 3 as opposite to an upper side in FIG. 2 .
  • the washer 22 , a plurality of the expansion-side damping valves 6 , the piston 4 , the washer 18 , a plurality of the compression-side damping valves 7 , and the valve stopper 19 are sequentially inserted, thereby forming the piston assembly body 28 .
  • the top end of the male screw portion 32 of the piston rod insert axis portion 3 in the piston assembly body 28 is screwed and fixed into the screw bore 11 of the piston rod 2 , thus completing the incorporation to the piston rod 2 .
  • piston assembly body 28 is not fixed to the piston rod insert axis portion 3 , the piston assembly body 28 does not drop down so long as the piston assembly body 28 is not positioned to be directed downwards, an assembly work efficiency can be maintained properly. And since the piston assembly body 28 is held between the piston nut 8 and a lower end of the piston rod 2 , the engagement member 31 becomes unnecessary, thus reducing the number of components and shortening an axial length of the piston.
  • the preferred embodiment differs from the preferred embodiment in FIG. 5 in that the piston nut 8 is formed integrally with the piston rod insert axis portion 3 .
  • the piston nut 8 is formed integrally with the piston rod insert axis portion 3 and the screw shaft 12 is formed in an end as opposite to the piston nut 8 to be screwed into the screw bore 11 of the piston rod 2 .
  • the male screw is not formed in a portion of the piston rod insert axis portion 3 into which the piston 4 or the like is inserted, there exists no clearance between the piston rod insert axis portion 3 and an inner peripheral surface of the expansion-side damping valve 6 , the compression-side damping valve 7 , or the piston, thus avoiding leakage of the operating oil.
  • an assembling process of the piston is the same as that in FIG. 5 .
  • the expansion-side damping valve 6 , the compression-side damping valve 7 , the piston 4 , and the like are incorporated into the piston rod insert axis portion 3 to form the piston assembly body 28 , and thereafter, the screw shaft 12 is screwed into the top end of the piston rod 2 to fix the piston assembly body 28 .
  • the piston rod insert axis portion and the base end of the piston rod are combined by a screw joint, but the present invention is not limited to this, and may adopt any fixation structure thereof.
US11/133,458 2004-05-27 2005-05-20 Structure of piston for hydraulic shock absorber Abandoned US20050263362A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2004157192A JP2005337382A (ja) 2004-05-27 2004-05-27 油圧緩衝器のピストン組付構造
JP2004-157192 2004-05-27

Publications (1)

Publication Number Publication Date
US20050263362A1 true US20050263362A1 (en) 2005-12-01

Family

ID=34936943

Family Applications (1)

Application Number Title Priority Date Filing Date
US11/133,458 Abandoned US20050263362A1 (en) 2004-05-27 2005-05-20 Structure of piston for hydraulic shock absorber

Country Status (3)

Country Link
US (1) US20050263362A1 (ja)
EP (1) EP1600661A1 (ja)
JP (1) JP2005337382A (ja)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9677640B2 (en) 2012-01-24 2017-06-13 Titus International Plc Damper assemblies

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102013008890A1 (de) * 2013-05-27 2014-08-28 Thyssenkrupp Bilstein Gmbh Schwingungsdämpfer für ein Fahrzeug

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4934491A (en) * 1987-12-14 1990-06-19 Atsugi Motor Parts Company, Limited Shock absorber with improved structure of thrusting piston assembly
US4989701A (en) * 1988-02-22 1991-02-05 Atsugi Motor Parts Company Ltd Shock absorber
US5207300A (en) * 1990-06-29 1993-05-04 Boge Aktiengesellschaft Hydraulic, adjustable vibration damper for motor vehicles
US5878852A (en) * 1995-09-29 1999-03-09 Kayaba Kogyo Kabushiki Kaisha Vehicular height control device
US6868947B2 (en) * 2000-10-20 2005-03-22 Krupp Bilstein Gmbh Piston for a hydraulic dashpot, and method of manufacturing such a piston

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP4048003B2 (ja) 1999-07-06 2008-02-13 カヤバ工業株式会社 油圧緩衝器のピストン組立体組付け方法
JP2003042209A (ja) * 2001-08-01 2003-02-13 Kayaba Ind Co Ltd ダンパー構造

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4934491A (en) * 1987-12-14 1990-06-19 Atsugi Motor Parts Company, Limited Shock absorber with improved structure of thrusting piston assembly
US4989701A (en) * 1988-02-22 1991-02-05 Atsugi Motor Parts Company Ltd Shock absorber
US5207300A (en) * 1990-06-29 1993-05-04 Boge Aktiengesellschaft Hydraulic, adjustable vibration damper for motor vehicles
US5878852A (en) * 1995-09-29 1999-03-09 Kayaba Kogyo Kabushiki Kaisha Vehicular height control device
US6868947B2 (en) * 2000-10-20 2005-03-22 Krupp Bilstein Gmbh Piston for a hydraulic dashpot, and method of manufacturing such a piston

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9677640B2 (en) 2012-01-24 2017-06-13 Titus International Plc Damper assemblies

Also Published As

Publication number Publication date
JP2005337382A (ja) 2005-12-08
EP1600661A1 (en) 2005-11-30

Similar Documents

Publication Publication Date Title
US8966752B2 (en) Shaft such as a camshaft for internal combustion engines
US5335757A (en) Hydraulic adjustable vibration damper
MXPA01003218A (es) Dispositivo para colocar, apretar o contraer un elemento de sujecion anular.
US4934491A (en) Shock absorber with improved structure of thrusting piston assembly
US4809651A (en) Valve tappet apparatus
US20050263362A1 (en) Structure of piston for hydraulic shock absorber
JPH0835546A (ja) 油圧式オートテンショナ
US7533646B2 (en) Balancing shaft for an internal combustion engine and a method for the production thereof
EP1253029A2 (en) A vehicle suspension
JP7369011B2 (ja) シリンダ装置
JP3062578B2 (ja) 油圧緩衝器のベースバルブ取付構造
JPH02286981A (ja) ボールバルブ
US6823769B2 (en) Device and method for fixing a piston or a piston rod attachment to a piston rod
JPS5918194Y2 (ja) シリンダ装置
JPS6329923Y2 (ja)
RU2070481C1 (ru) Патрон для крепления осевого инструмента
JP7378343B2 (ja) ピストンロッドアセンブリ、緩衝器およびピストンロッドアセンブリの製造方法
US11261765B1 (en) Control valve assembly of a variable cam timing phaser
JP2003172392A (ja) バルブボディの定着構造
JP3573169B2 (ja) フロントフォーク
JPH0728430Y2 (ja) 液圧緩衝器のピストンバルブ取付構造
KR100914595B1 (ko) 피스톤 로드의 체결 지그
KR100217608B1 (ko) 쇽업쇼바의 부품 분해 조립용 지그
KR100598835B1 (ko) 신장부를 구비한 쇼크업소버
JPH0640342Y2 (ja) 減衰力可変型液圧緩衝器

Legal Events

Date Code Title Description
AS Assignment

Owner name: KAYABA INDUSTRY CO., LTD., JAPAN

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:OOTA, AKIHISA;NORITAKE, ATSUSHI;REEL/FRAME:016887/0817

Effective date: 20050628

STCB Information on status: application discontinuation

Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION