Patent US4078778A successfully refreshed from Google Patents.
US4078778A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Gas spring
Assignee: Stabilus GmbH
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Filing: 1976-09-09
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Granted: 1978-03-14
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Expires: 1996-09-09
Abstract
Abstract In a gas spring having a cylinder and a piston rod movable within the cylinder, braking elements are provided which brake or block the movement of the piston rod with respect to the cylinder when the interior pressure within the cylinder is reduced below a predetermined pressure. So the risk is eliminated that the piston rod when under load is unintentionally moved into the cylinder with a high velocity when the gas pressure within the cylinder is lowered below the predetermined pressure. The braking elements are spring loaded and are held in an inoperative position by adequate pressure within the cylinder.
Inventors
- 👤 Franz-Josef Hubweber
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 04:16
CPC Classifications
F; F16; F16F; F16F9/00; F16F9/02; F16F9/0209; F16F9/0245; F16F9/0254
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
156 words
A gas spring comprising: (a) a cylinder having an axis and radially defining therein a cavity closed in one axial direction; (b) sealing means axially defining said cavity in the other axial direction; (c) a piston rod sealingly engaged by said sealing means for axial movement inward and outward of said cavity; (d) a body of gas in said cavity, the pressure of said gas being at least equal to atmospheric pressure and biasing said piston rod outward of said cavity when the pressure thereof is higher than atmospheric pressure; (e) braking means secured to said cylinder; (f) spring means mounted on said cylinder and biasing said braking means toward a position of engagement with said piston rod, said braking means impeding said movement when in said position; and (g) holding means secured to said cylinder and responsive to a predetermined minimum pressure of said gas for preventing movement of said braking means into said position.
Claim 2
Dependent Claim
156 words
A gas spring comprising: (a) a cylinder having an axis and radially defining therein a cavity closed in one axial direction; (b) sealing means axially defining said cavity in the other axial direction; (c) a piston rod sealingly engaged by said sealing means for axial movement inward and outward of said cavity; (d) a body of gas in said cavity, the pressure of said gas being at least equal to atmospheric pressure and biasing said piston rod outward of said cavity when the pressure thereof is higher than atmospheric pressure; (e) braking means secured to said cylinder; (f) spring means mounted on said cylinder and biasing said braking means toward a position of engagement with said piston rod, said braking means impeding said movement when in said position; and (g) holding means secured to said cylinder and responsive to a predetermined minimum pressure of said gas for preventing movement of said braking means into said position.
Claim 3
Dependent Claim
24 words
A gas spring according to claim 1, wherein said braking means in said position thereof prevent said inward axial movement of said piston rod.
Claim 4
Dependent Claim
35 words
A gas spring according to claim 2, wherein said holding means include a movable wall member in said cylinder, said gas and said spring means exerting pressure on said wall member in opposite respective diections.
Claim 5
Dependent Claim
39 words
A gas spring according to claim 3, wherein said wall member is formed with a passage extending axially therethrough and receiving said piston rod, said sealing means sealing said wall member to said piston rod and to said cylinder.
Claim 6
Dependent Claim
42 words
A gas spring according to claim 4, wherein said spring means are annular about said piston rod, respective radially extending faces of said wall member being directed axially inwardly and outwardly of said cavity, said spring means engaging said outwardly directed face.
Claim 7
Dependent Claim
27 words
A gas spring according to claim 5, further comprising means axially defining a chamber in said cylinder communicating with the ambient atmosphere and receiving said spring means.
Claim 8
Dependent Claim
17 words
A gas spring according to claim 5, wherein said spring means include at least one cup spring.
Claim 9
Dependent Claim
77 words
A gas spring according to claim 1, wherein said braking means include a collet chuck having a collet member receiving said piston rod and a clamping member engageable with said collet member for tightening said collet member about said piston rod, one of said members of the chuck being axially secured to said cylinder, and the other member of said chuck being axially movable in response to forces exerted by said spring means and said holding means.
Claim 10
Dependent Claim
47 words
A gas spring according to claim 8, wherein said clamping member is apertured and has an inner face in the aperture thereof, said collet member being received in said aperture and having an outer face opposite said inner face, at least one of said faces being conical.
Claim 11
Dependent Claim
15 words
A gas spring according to claim 8, wherein said one member is said clamping member.
Claim 12
Dependent Claim
26 words
A gas spring according to claim 10, wherein said holding means include a wall member axially movable in said cylinder and secured to said collet member.
Claim 13
Dependent Claim
48 words
A gas spring according to claim 11, wherein said sealing means seal said wall member to said cylinder, said wall member bounding said cavity, said collet member extending inward of said cavity from said wall member, and said clamping member being secured to said cylinder in said cavity.
Claim 14
Dependent Claim
35 words
A gas spring according to claim 11, wherein said clamping member is axially offset from said wall member outward of said cavity, and said collet member extends from said wall member toward said clamping member.
Claim 15
Dependent Claim
30 words
A gas spring according to claim 13, wherein said collet member has an annular disc portion having two radially extending faces respectively engaging said spring means and said wall member.
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) | 1981-03-13 | 1981-09-12 | 1982-03-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-03-13 | 1985-09-12 | 1986-03-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-03-13 | 1989-09-12 | 1990-03-14 | $7700.00 | Window Closed / Lapsed |