Patent US3812938A successfully refreshed from Google Patents.
US3812938A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Shock absorber
Assignee: Tenneco Automotive Europe BVBA
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Filing: 1972-03-30
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Granted: 1974-05-28
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Expires: 1992-03-30
Abstract
Abstract A shock absorber comprising an elongated cylindrical pressure cylinder having a piston reciprocally disposed therewithin and connected to a piston rod extending outwardly from one end thereof, the piston rod carrying a dirt shield which extends coaxially of the pressure cylinder and in partial surrounding relationship therewith. The pressure cylinder is adapted to be filled with preselected quantities of a hydraulic damping fluid and a pressurized gas for damping reciprocal movement of the piston therewithin. The piston is provided with a novel valve arrangement which controls the compression and rebound characteristics of the shock absorber, and one end of the pressure cylinder is provided with a novel rod guide assembly which is designed so as to provide for convenient charging of the cylinder with the aforesaid pressurized gas. The interior of the pressure cylinder is provided with a generally helically shaped baffle arrangement which is compressible axially within the cylinder in response to reciprocal movement of the piston therein and functions to prevent undesirable foaming or aeration of the hydraulic fluid during operation of the shock absorber.
Inventors
- 👤 J Fader
- 👤 R Beets
- 👤 J Keijzer
- 👤 M Graulus
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 16:39
CPC Classifications
F; F16; F16F; F16F9/00; F16F9/32; F16F9/38; F16F9/10; F16F9/14; F16F9/16; F16F9/18; F16F9/19; F16F9/36; F16F9/362
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
257 words
In combination in a hydraulic shock absorber, a hollow cylinder member, a piston reciprocable within said member, a piston rod connected to said piston and extending axially outwardly from one end of said member, an annular rod guide secured within and closing one end of said cylinder member and defining an axially extending bore through which said piston rod extends, a cylindrical anti-friction bushing fabricated of low coefficient of friction polymeric material secured within said bore, a first enlarged diameter counterbore formed at one end of said guide member coaxially of said bore, a generally cup-shaped seal support member disposed within said counterbore and abuttingly engaged with one axial end of said bushing for preventing axial movement thereof toward said counterbore, an annular fluid seal disposed within said support member having an inner peripheral portion slidably sealingly engaged with the outer periphery of said piston rod, a radial shoulder projecting interiorly of said bore at the end thereof opposite said counterbore, said shoulder being abuttingly engaged with the other axial end of said bushing, whereby said bushing is retained between said shoulder and said cup member against any axial displacement relative to said guide member, a second enlarged diameter counterbore formed at the opposite end of said guide member from said first mentioned counterbore, an annular fluid seal disposed within said second counterbore and adapted for sliding sealing engagement with the outer periphery of said piston rod, and a retaining plate nestingly received within another counterbore adjacent said second counterbore for retaining said last mentioned seal therewithin.
Claim 2
Dependent Claim
257 words
In combination in a hydraulic shock absorber, a hollow cylinder member, a piston reciprocable within said member, a piston rod connected to said piston and extending axially outwardly from one end of said member, an annular rod guide secured within and closing one end of said cylinder member and defining an axially extending bore through which said piston rod extends, a cylindrical anti-friction bushing fabricated of low coefficient of friction polymeric material secured within said bore, a first enlarged diameter counterbore formed at one end of said guide member coaxially of said bore, a generally cup-shaped seal support member disposed within said counterbore and abuttingly engaged with one axial end of said bushing for preventing axial movement thereof toward said counterbore, an annular fluid seal disposed within said support member having an inner peripheral portion slidably sealingly engaged with the outer periphery of said piston rod, a radial shoulder projecting interiorly of said bore at the end thereof opposite said counterbore, said shoulder being abuttingly engaged with the other axial end of said bushing, whereby said bushing is retained between said shoulder and said cup member against any axial displacement relative to said guide member, a second enlarged diameter counterbore formed at the opposite end of said guide member from said first mentioned counterbore, an annular fluid seal disposed within said second counterbore and adapted for sliding sealing engagement with the outer periphery of said piston rod, and a retaining plate nestingly received within another counterbore adjacent said second counterbore for retaining said last mentioned seal therewithin.
Claim 3
Dependent Claim
44 words
The invention as set forth in claim 1 which includes an annular ring interposed between the outer periphery of said rod guide and the inner periphery of said cylindrical member for retaining said rod guide at a preselected axial position within said cylindrical member.
Claim 4
Dependent Claim
28 words
The invention as set forth in claim 1 which includes an end cap member for supporting said rod guide at a preselected axial position within said cylindrical member.
Claim 5
Dependent Claim
57 words
The invention as set forth in claim 1 wherein said first mentioned fluid seal is disposed at the axially outer end of said cylindrical member and is adapted to operate as a wiping element to prevent road dirt, moisture or the like from entering between the exterior of said piston rod and the interior of said bushing.
Claim 6
Dependent Claim
15 words
The invention as set forth in claim 1 wherein said bushing is fabricated of Teflon.
Claim 7
Dependent Claim
37 words
The invention as set forth in claim 1 which includes means for exerting a resilient radial force against one of said fluid seals for urging the same into engagement with the outer periphery of said piston rod.
Claim 8
Dependent Claim
18 words
The invention as set forth in claim 6 wherein said radial force applying means comprises a garter spring.
Claim 9
Dependent Claim
23 words
The invention as set forth in claim 6 wherein said radial force applying means is operatively associated with said second mentioned fluid seal.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-05-27 | 1977-11-26 | 1978-05-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-05-27 | 1981-11-26 | 1982-05-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-05-27 | 1985-11-26 | 1986-05-28 | $7700.00 | Window Closed / Lapsed |