US4076214A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Double-acting jack having a position stop
Assignee: Individual
•
Filing: 1976-12-20
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Granted: 1978-02-28
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Expires: 1996-12-20
Abstract
Abstract A double-acting jack having a working chamber is fitted with an adjustable stop against which its piston comes to rest. The stop is constituted by a nonrotatable nut, which is axially displaceable by an axially nondisplaceable lead screw with which it meshes. The stop includes means for controlling the supply of pressurized fluid from a supply line to the working chamber, the supply line being opened whenever the piston and its associated rod are not in the end-of-stroke position and closed whenever the piston and its rod are in the end-of-stroke position. The lead screw is mounted to have a slight amount of axial play. The supply line terminates in an annular opening provided on a shoulder of the lead screw, which defines a valve, or in it seat.
Inventors
- 👤 Pierre Colly
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 06:26
CPC Classifications
F; F15; F15B; F15B15/00; F15B15/20; F15B15/24; B; B30; B30B; B30B15/00; B30B15/16; B30B15/18
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
150 words
In a double-acting jack fitted with an adjustable positive mechanical stop, against which its piston comes to rest and having a working chamber, the positive mechanical stop being constituted by a nonrotatable nut, the nut being axially displaceable by an axially nondisplaceable lead screw with which it meshes, and the screw being capable of being set in rotation for the purpose of adjusting the position of the nut, the improvement wherein said positive mechanical stop which limits the stroke of said piston includes means for controlling the supply of pressurized fluid from a supply line to said working chamber of the jack by opening the supply line to said working chamber when the fluid is pressurized and said piston and said rod are not at a given end-of-stroke position and by closing the supply line to said chamber as soon as said piston and said rod reach the end-of-stroke position.
Claim 2
Dependent Claim
150 words
In a double-acting jack fitted with an adjustable positive mechanical stop, against which its piston comes to rest and having a working chamber, the positive mechanical stop being constituted by a nonrotatable nut, the nut being axially displaceable by an axially nondisplaceable lead screw with which it meshes, and the screw being capable of being set in rotation for the purpose of adjusting the position of the nut, the improvement wherein said positive mechanical stop which limits the stroke of said piston includes means for controlling the supply of pressurized fluid from a supply line to said working chamber of the jack by opening the supply line to said working chamber when the fluid is pressurized and said piston and said rod are not at a given end-of-stroke position and by closing the supply line to said chamber as soon as said piston and said rod reach the end-of-stroke position.
Claim 3
Dependent Claim
91 words
An improved double-acting jack according to claim 1, including a bottom plate and wherein said lead screw is mounted with a slight amount of axial play, a portion of said screw being located on said bottom plate of the jack and being provided with a shoulder, said shoulder being turned toward the inside of the jack and constituting a check valve whose seat is located in said plate, said supply line for the pressurized fluid terminating in an annular opening provided in said shoulder forming the valve of said lead screw.
Claim 4
Dependent Claim
79 words
An improved double-acting jack according to claim 1, including a bottom plate and wherein said lead screw is mounted with a slight amount of axial play, a portion of said screw being located on said bottom plate of the jack and being provided with a shoulder, said shoulder being turned toward the inside of the jack and constituting a check valve whose seat is located in said plate, said supply line for the pressurized fluid terminating in said seat.
References Cited (Backward Citations)
US3951042A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-02-27 | 1981-08-29 | 1982-02-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-02-27 | 1985-08-29 | 1986-02-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-02-27 | 1989-08-29 | 1990-02-28 | $7700.00 | Window Closed / Lapsed |