Patent US6006086A successfully refreshed from Google Patents.
Patent US4776440A successfully refreshed from Google Patents.
US4776440A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Shock absorber with resiliently biased adjustment piston
Assignee: Piolax Inc
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Filing: 1985-12-03
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Granted: 1988-10-11
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Expires: 2005-12-03
Abstract
Abstract A shock absorber comprises a cylinder with a cylindrical bore, an actuator piston with a rod slidably received in the bore, and an adjustment piston slidably received in the bore and resiliently kept in a predetermined position. The adjustment piston cooperates with the actuator piston to define an adjustment chamber therebetween. The adjustment piston is movable in response to pressure developing within the adjustment chamber to vary a rate of air flow between the adjustment chamber and the ambient atmosphere so as to decelerate the actuator piston during its extending movement relative to the cylinder, thus providing a slow and gradual extending movement of the actuator piston.
Inventors
- 👤 Katsumi Yamada
- 👤 Toshinari Hojima
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 22:50
CPC Classifications
F; F16; F16F; F16F9/00; F16F9/02; F16F9/0209; F16F9/0245; F16F9/06; F16F9/32; F16F9/48; F16F9/49
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
170 words
A shock absorber comprising: a cylinder having a bore and a peripheral wall about an axis defining said bore, an actuator piston including a piston head disposed in said bore and slidably engaging said wall at a point along its axis and a rod extending out of said cylinder, an adjustment piston disposed in said bore and slidably engaging said wall at a point along its axis to cooperate with said piston head engagement point to define an adjustment chamber within said cylinder bore between the adjustment piston engagement point and piston head engagement point, a plurality of longitudinally disbursed passages through said wall between said bore and the ambient atmosphere, and means for resiliently biasing said adjustment piston with said adjustment piston engagement point at a predetermined position along the axis of the cylinder between two of the passages and allowing said adjustment piston to move longitudinally within said bore to vary a rate of fluid flow through said passages in response to forces applied to said actuator piston.
Claim 2
Dependent Claim
170 words
A shock absorber comprising: a cylinder having a bore and a peripheral wall about an axis defining said bore, an actuator piston including a piston head disposed in said bore and slidably engaging said wall at a point along its axis and a rod extending out of said cylinder, an adjustment piston disposed in said bore and slidably engaging said wall at a point along its axis to cooperate with said piston head engagement point to define an adjustment chamber within said cylinder bore between the adjustment piston engagement point and piston head engagement point, a plurality of longitudinally disbursed passages through said wall between said bore and the ambient atmosphere, and means for resiliently biasing said adjustment piston with said adjustment piston engagement point at a predetermined position along the axis of the cylinder between two of the passages and allowing said adjustment piston to move longitudinally within said bore to vary a rate of fluid flow through said passages in response to forces applied to said actuator piston.
Claim 3
Dependent Claim
46 words
A shock absorber as claimed in claim 1 wherein said passages include a first passage most distal from said piston head and larger than all other passages and said predetermined position of the adjustment piston engagement point is between said first passage and an adjacent passage.
Claim 4
Dependent Claim
45 words
A shock absorber as claimed in claim 1, wherein said cylinder has an apertured end wall closing one end of said bore, and said biasing means includes a spring having one end engaging said adjustment piston and an opposite end engaging said apertured end wall.
Claim 5
Dependent Claim
41 words
A shock absorber as claimed in claim 3, wherein said actuator piston has a position where said piston head provides a postive connection with said adjustment piston and said spring is preloaded to bias said adjustment piston and said actuator piston.
Claim 6
Dependent Claim
37 words
A shock absorber as claimed in claim 4, wherein said piston head and said adjustment piston have conical projections which extend into said adjustment chamber and come into contact with each other to provide said positive connection.
Claim 7
Dependent Claim
36 words
A shock absorber as claimed in claim 5, wherein said cylinder has an open end at an end of said bore which is opposite to said apertured end wall, said rod extending through said open end.
References Cited (Backward Citations)
US334105A
Cited
US1254106A
Cited
GB244550A
Cited
US1744514A
Cited
DE1834295U
Cited
US3218849A
Cited
US3307842A
Cited
US3531065A
Cited
DE2153285A1
Cited
DE2237914A1
Cited
DE2757711A1
Cited
JPS58174038A
Cited
JPS5927558A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-10-11 | 1992-04-11 | 1992-10-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-10-11 | 1996-04-11 | 1996-10-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-10-11 | 2000-04-11 | 2000-10-11 | $7700.00 | Window Closed / Lapsed |