Patent US3890884A successfully refreshed from Google Patents.
US3890884A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Hydraulic actuator
Assignee: BorgWarner Automotive Transmission and Engine Component Corp
•
Filing: 1973-11-23
•
Granted: 1975-06-24
•
Expires: 1993-11-23
Abstract
Abstract An hydraulic actuator has a cup-like piston with a thrust assembly nested therein which is rockably mounted in the piston to avoid eccentric loading of the piston. A resilient collar resets or restores the thrust assembly to a centered position after each actuation. The apparatus is particularly advantageous where a compact actuator is required having a piston in which the head diameter is large relative to its length.
Inventors
- 👤 Russell E Silberschlag
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 02:39
CPC Classifications
F; F16; F16J; F16J1/00; F16J1/10; F16J1/14; F16J1/22; F16D; F16D55/00; F16D55/02; F16D55/22; F16D55/224; F16D55/225; F16D55/2255; F16D2125/00; F16D2125/02; F16D2125/06; F16D2125/18; F16D2125/58; F16D2125/587; Y; Y10; Y10T; Y10T403/00; Y10T403/32; Y10T403/32606; Y10T403/32631; Y10T403/32811
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
242 words
An hydraulic actuator comprising a housing member including a substantially cylindrical chamber opening outwardly through a wall thereof and a generally cup shaped piston slidably received within said chamber and adapted to move outwardly in response to fluid pressure in said chamber, said piston including head and skirt wall portions defining a central cavity opening outwardly of said actuator, said head portion including a seat in said cavity remote from the open end thereof, and a thrust assembly extending into said central cavity having an annular foot disposed outwardly of said piston, a strut having a head portion engageable with said seat extending through said central cavity between said annular foot and said piston head wall, and a resilient collar embracing said strut adjacent said annular foot having intersecting planar surfaces thereon defining a peripheral sharp edge frictionally engaging said skirt portion of said piston, said resilient collar being an elastomeric sleeve including a pair of spaced annular portions, one of said annular portions defining said sharp peripheral edge engaging said piston skirt adjacent said annular foot, and the other of said annular portions having a face abutting said piston head wall portion outwardly of said seat, said collar peripheral edge yieldably urging said strut toward a centered position with respect to said piston skirt permitting displacement of said strut from said centered position under load while substantiallY isolating said piston skirt from lateral forces imposed on said thrust assembly under load.
Claim 2
Dependent Claim
242 words
An hydraulic actuator comprising a housing member including a substantially cylindrical chamber opening outwardly through a wall thereof and a generally cup shaped piston slidably received within said chamber and adapted to move outwardly in response to fluid pressure in said chamber, said piston including head and skirt wall portions defining a central cavity opening outwardly of said actuator, said head portion including a seat in said cavity remote from the open end thereof, and a thrust assembly extending into said central cavity having an annular foot disposed outwardly of said piston, a strut having a head portion engageable with said seat extending through said central cavity between said annular foot and said piston head wall, and a resilient collar embracing said strut adjacent said annular foot having intersecting planar surfaces thereon defining a peripheral sharp edge frictionally engaging said skirt portion of said piston, said resilient collar being an elastomeric sleeve including a pair of spaced annular portions, one of said annular portions defining said sharp peripheral edge engaging said piston skirt adjacent said annular foot, and the other of said annular portions having a face abutting said piston head wall portion outwardly of said seat, said collar peripheral edge yieldably urging said strut toward a centered position with respect to said piston skirt permitting displacement of said strut from said centered position under load while substantiallY isolating said piston skirt from lateral forces imposed on said thrust assembly under load.
Claim 3
Dependent Claim
36 words
An actuator according to claim 1, said strut including a projection defining a shoulder remote from said head portion thereof, said annular foot being of frusto-conical configuration having a central portion thereof bearing against said shoulder.
Claim 4
Dependent Claim
40 words
An actuator according to claim 1, said piston skirt wall portion including rib portions projecting into said cavity and merging into said head portion, said collar including a yieldable annular portion defining said sharp peripheral edge engaging said rib portions.
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) | 1978-06-23 | 1978-12-23 | 1979-06-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-06-23 | 1982-12-23 | 1983-06-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-06-23 | 1986-12-23 | 1987-06-24 | $7700.00 | Window Closed / Lapsed |