US3762514A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Support column of adjustable length
Assignee: Stabilus Industrie und Handels GmbH
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Filing: 1971-05-17
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Granted: 1973-10-02
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Expires: 1991-05-17
Abstract
Abstract In a column of adjustable length having a cylinder, a piston assembly movable in the cylinder cavity and partly projecting from the same in an axial direction, a first or primary valve operable from outside the cylinder cavity which is divided by the piston assembly into two compartments, and a liquid filling the cylinder cavity except for a cushion of compressed gas, the movement of the piston assembly against the restraint of the gas cushion is blocked by a second, automatic valve in a fixed partitition wall between the piston and the gas cushion in response to sudden movement of the piston assembly inward of the cylinder.
Inventors
- 👤 H Freitag
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 00:14
CPC Classifications
F; F16; F16F; F16F9/00; F16F9/32; F16F9/56; A; A47; A47C; A47C3/00; A47C3/20; A47C3/30
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
277 words
A column of adjustable length comprising, in combination: a. a cylinder member having an axis and enclosing a cavity; b. a piston member movable axially in said cavity and dividing the same into two compartments; c. a piston rod member fixedly fastened to said piston member and extending from the same axially outward of said cavity; d. first valve means operably interposed between said compartments; e. first valve operating means accessible from outside said cavity for moving said valve means toward and away from a position in which said valve means seals said compartments from each other; f. a body of liquid filling one of said compartments and a portion of the other compartment in all operative positions of said piston member; g. a body of gas under a pressure higher than atmospheric pressure filling the remainder of said other compartment; h. a wall member in said portion of said other compartment and dividing the same into one part adjacent said piston member and remote from said body of gas, and another part adjacent said body of gas and remote from said piston member; i. means defining a passage connecting said parts; j. second valve means movable toward and away from a position in which said second valve means prevents liquid flow through said passage; k. second valve operating means responsive to an increase in liquid pressure in said one part for moving said second valve means into said position thereof; and l. biasing means biasing said second valve means away from said position thereof with a force sufficient to maintain liquid flow through said passage until said pressure in said one part exceeds a predetermined value.
Claim 2
Dependent Claim
277 words
A column of adjustable length comprising, in combination: a. a cylinder member having an axis and enclosing a cavity; b. a piston member movable axially in said cavity and dividing the same into two compartments; c. a piston rod member fixedly fastened to said piston member and extending from the same axially outward of said cavity; d. first valve means operably interposed between said compartments; e. first valve operating means accessible from outside said cavity for moving said valve means toward and away from a position in which said valve means seals said compartments from each other; f. a body of liquid filling one of said compartments and a portion of the other compartment in all operative positions of said piston member; g. a body of gas under a pressure higher than atmospheric pressure filling the remainder of said other compartment; h. a wall member in said portion of said other compartment and dividing the same into one part adjacent said piston member and remote from said body of gas, and another part adjacent said body of gas and remote from said piston member; i. means defining a passage connecting said parts; j. second valve means movable toward and away from a position in which said second valve means prevents liquid flow through said passage; k. second valve operating means responsive to an increase in liquid pressure in said one part for moving said second valve means into said position thereof; and l. biasing means biasing said second valve means away from said position thereof with a force sufficient to maintain liquid flow through said passage until said pressure in said one part exceeds a predetermined value.
Claim 3
Dependent Claim
275 words
A column of adjustable length comprising, in combination: a. a cylinder member having an axis and enclosing a cavity; b. a piston member movable axially in said cavity and dividing the same into two compartments; c. a piston rod member fixedly fastened to said piston member and extending from the same axially outward of said cavity; d. first valve means operably interposed between said compartments; e. first valve operating means accessible from outside said cavity for moving said valve means toward and away from a position in which said valve means seals said compartments from each other; f. a body of liquid filling one of said compartments and a portion of the other compartment in all operative positions of said piston member; g. a body of gas under a pressure higher than atmospheric pressure filling the remainder of said other compartment; h. a wall member in said portion of said other compartment and dividing the same into one part adjacent said piston member and remote from said body of gas, and another part adjacent said body of gas and remote from said piston member; i. means defining a passage connecting said parts; j. second valve means movable toward and away from a position in which said second valve means prevents liquid flow through said passage; k. second valve operating means responsive to liquid flow from said one part to said other part for moving said second valve means into said position thereof; and l. yieldably resilient means biasing said second valve means away from said position thereof with a force sufficient to maintain liquid flow through said passage until said flow exceeds a predetermined rate.
Claim 4
Dependent Claim
275 words
A column of adjustable length comprising, in combination: a. a cylinder member having an axis and enclosing a cavity; b. a piston member movable axially in said cavity and dividing the same into two compartments; c. a piston rod member fixedly fastened to said piston member and extending from the same axially outward of said cavity; d. first valve means operably interposed between said compartments; e. first valve operating means accessible from outside said cavity for moving said valve means toward and away from a position in which said valve means seals said compartments from each other; f. a body of liquid filling one of said compartments and a portion of the other compartment in all operative positions of said piston member; g. a body of gas under a pressure higher than atmospheric pressure filling the remainder of said other compartment; h. a wall member in said portion of said other compartment and dividing the same into one part adjacent said piston member and remote from said body of gas, and another part adjacent said body of gas and remote from said piston member; i. means defining a passage connecting said parts; j. second valve means movable toward and away from a position in which said second valve means prevents liquid flow through said passage; k. second valve operating means responsive to liquid flow from said one part to said other part for moving said second valve means into said position thereof; and l. yieldably resilient means biasing said second valve means away from said position thereof with a force sufficient to maintain liquid flow through said passage until said flow exceeds a predetermined rate.
Claim 5
Dependent Claim
27 words
A column as set forth in claim 2, further comprising fastening means fastening said wall member to said cylinder in sealing engagment in a fixed axial position.
Claim 6
Dependent Claim
29 words
A column as set forth in claim 2, said yieldably resilient means including spring means having two spaced portions respectively engaging said wall members and said second valve means.
Claim 7
Dependent Claim
16 words
A column as set forth in claim 2, said yieldably resilient means including a cup spring.
Claim 8
Dependent Claim
29 words
A column as set forth in claim 2, further comprising a partition member axially movable in said cavity in sealing engagement with said cylinder member and separating said bodies.
Claim 9
Dependent Claim
86 words
A column as set forth in claim 2, said piston member and said piston rod member jointly constituting a piston assembly, said assembly being formed with a conduit (19, 20, 21) connecting said two compartments, said first valve means including a valve member movable relative to said conduit in an axial direction between a conduit-opening position and a conduit-closing position, and said first valve operating means including an operating member received in said piston rod member for axial movement and fixedly secured to said valve member.
Claim 10
Dependent Claim
36 words
A column as set forth in claim 2, the pressure of said body of gas being sufficient to drive said piston rod member outward of said cavity when said first and second valve means are open.
Claim 11
Dependent Claim
58 words
A column as set forth in claim 2, said second valve operating means including an operating member having two opposite faces respectively exposed to said liquid in said two parts when said second valve means is away from said position thereof, and a motion transmitting member connecting said operating member to said second valve means for joint movement.
Claim 12
Dependent Claim
65 words
A column as set forth in claim 9, said wall member being formed with a bore constituting said passage, said bore having two orifices communicating with said two parts respectively, said motion transmitting member being received in said bore with a clearance sufficient for flow of liquid between said two parts, said second valve means and said operating member being located adjacent said orifices respectively.
Claim 13
Dependent Claim
56 words
A column as set forth in claim 10, said clearance constituting an annular gap about said motion transmitting member, said operating member being formed with a throttling opening therethrough communicating with said gap and with one of said two parts and constituting said passage, said second valve means when in said position thereof closing said gap.
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) | 1976-10-01 | 1977-04-02 | 1977-10-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-10-01 | 1981-04-02 | 1981-10-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-10-01 | 1985-04-02 | 1985-10-02 | $7700.00 | Window Closed / Lapsed |