US3554528A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Energy dissipating hydraulic systems
Assignee: Individual
•
Filing: 1967-09-21
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Granted: 1971-01-12
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Expires: 1987-09-21
Abstract
Abstract Improvements in energy dissipating hydraulic systems are disclosed for dissipating the energy of impacting forces comprising an industrial-type hydraulic shock absorber having an hydraulic ram chamber and an hydraulic ram operative therein which has a single energy dissipating power stroke in respect to an impacting force acting in one direction thereon. A selfcontained hydraulic reservoir, a piston therein and yieldable means operative upon said piston are provided. Means interconnecting the ram chamber and the reservoir are provided so that a transfer of hydraulic liquid occurs in opposition to said yieldable means from said ram chamber to said reservoir under relatively free flow conditions for a first part of said power stroke and under flow restriction conditions for the remainder thereof. Said ram chamber provided with axially spaced orifices all but the last of which are closed off progressively by said hydraulic ram in its movement to its retracted position in said ram chamber during said power stroke. The first of said orifices being free flow orifices through which hydraulic liquid flows from said ram chamber to said reservoir under free flow conditions for a first part of said power stroke and the remainder of said orifices being flow restriction orifices through which hydraulic liquid flows from said ram chamber to said reservoir under flow restriction conditions for the remainder of said power stroke. Said hydraulic ram being fully retracted without closing off the last of said flow restriction orifices. At the end of the power stroke the reservoir piston effects a return of hydraulic liquid from the reservoir to the ram chamber to return the ram in the opposite direction in a single return stroke thereof. Said interconnecting means includes unidirectional valve means closed during said power stroke and open to the ram chamber during said return stroke.
Inventors
- 👤 Joseph R Kring
- 👤 Josef F Schraner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 18:47
CPC Classifications
F; F16; F16F; F16F9/00; F16F9/32; F16F9/44
Claims Analysis
Total Claims: 30
Claim 1
Independent Claim
383 words
Means in energy dissipating hydraulic systems for dissipating the energy of impacting forces comprising: a. an hydraulic ram chamber and an hydraulic ram operative out of one end thereof, said ram having a single energy dissipating power stroke in respect to an impacting force acting in one direction thereon; b. an hydraulic reservoir, a piston operative therein, and yieldable means operative upon said piston; c. means interconnecting said ram chamber and said reservoir so that a transfer of hydraulic liquid occurs in opposition to said yieldable means from said ram chamber to said reservoir under relatively free flow conditions for a first part of said power stroke and under flow restriction conditions for the remainder thereof; d. said ram chamber provided with axially spaced orifices all but the last of which are closed off progressively by said hydraulic ram in its movement to its retracted position in said ram chamber during said power stroke; the first of said orifices being free flow orifices through which hydraulic liquid flows from said ram chamber to said reservoir under free flow conditions for a first part of said power stroke and the remainder of said orifices being flow restriction orifices through which hydraulic liquid flows from said ram chamber to said reservoir under flow restriction conditions for the remainder of said power stroke; said hydraulic ram being fully retracted without closing off the last of said flow restriction orifices; e. said reservoir piston operative at the end of said power stroke to effect return of hydraulic liquid from the reservoir to the ram chamber to return the ram in the opposite direction in a single rapid return stroke thereof; and f. said interconnecting means including unidirectional valve means at the end of said ram chamber opposite that from which said ram operates which is closed during said power stroke and open to the ram chamber during said return stroke. . 2. Means according to claim 1 further comprising means for varying the area of said flow restriction orifices comprising concentric cylinders which have communicating flow restriction orifices and means for rotating said cylinders relative to each other to vary the effective flow area of said flow restriction orifices to alter the cushioning effect of said power stroke in accordance with the magnitude of the impacting force.
Claim 2
Dependent Claim
34 words
Means according to claim 2 in which the outer cylinder is provided with axially spaced slits and means for rotating said outer cylinder relative to the inner cylinder to vary said effective flow area.
Claim 3
Dependent Claim
42 words
Means according to claim 1 further comprising houSing means for the reservoir and said chamber having cooling fins on the exterior thereof for transfering heat from said hydraulic liquid to ambient air during both said power and return strokes for cooling purposes.
Claim 4
Dependent Claim
34 words
Means according to claim 1 in which the reservoir piston is provided with axially separable valve means permitting flow of hydraulic liquid through said piston during filling of said reservoir to prevent overfilling thereof.
Claim 5
Dependent Claim
24 words
An hydraulic shock absorber according to claim 1 having housing means with fins on its exterior for cooling hydraulic liquid therein via ambient air.
Claim 6
Dependent Claim
37 words
An hydraulic shock absorber according to claim 1 in which said ram includes a hard aluminum bronze piston sleeve and a pair of piston rings therefor and held thereon in diametrically opposed circumferential relationship to each other.
Claim 7
Dependent Claim
29 words
An hydraulic shock absorber according to claim 1 further comprising an end cap for the free end of said ram and resilient releasable holding means for said end cap.
Claim 8
Dependent Claim
30 words
An hydraulic shock absorber according to claim 8 further comprising an arcuately contoured impact plate for use in conjunction with said end cap for reducing side thrust on said ram.
Claim 9
Dependent Claim
48 words
An hydraulic shock absorber according to claim 1 in which the wall of said reservoir is provided by a honed liner and in which said yieldable means comprises compression spring means operating on the reservoir piston to maintain the hydraulic liquid in the reservoir under a yieldable pressure.
Claim 10
Dependent Claim
43 words
An hydraulic shock absorber according to claim 9 in which the reservoir piston is provided with liquid-tight seal means in respect to said liner and a piston ring in advance of said seal means to absorb surge hydraulic pressures on the reservoir piston.
Claim 11
Dependent Claim
31 words
An hydraulic shock absorber according to claim 3 in which said means for rotating said outer cylinder comprises a driftless gear train including a worm and a manually rotated knurled knob.
Claim 12
Dependent Claim
27 words
An hydraulic shock absorber according to claim 12 in which graduated readout means are provided on the gear train for determining the setting of said metering orifice.
Claim 13
Dependent Claim
34 words
An hydraulic shock absorber according to claim 13 in which said gear train includes a gear segment meshing with said worm and a bifurcated mechanism centering said gear segment in respect to said worm.
Claim 14
Dependent Claim
55 words
An hydraulic shock absorber according to claim 1 in which said reservoir piston comprises valve means including an axially moveable valve stem and liquid-tight seal means therefor and means to open said valve means when the reservoir piston reaches a predetermined position in its travel during filling of the shock absorber to prevent overfilling thereof.
Claim 15
Dependent Claim
33 words
An hydraulic shock absorber according to claim 3 in which said inner cylinder has a series of flats on its exterior circumferential surface and radial apertures through its wall intersection each such flat.
Claim 16
Dependent Claim
37 words
An hydraulic shock absorber according to claim 3 in which said flow restriction orifice on said outer cylinder comprises a series of annular grooves and a tangential flow restriction slot through its wall intersecting each such groove.
Claim 17
Dependent Claim
36 words
An hydraulic shock absorber according to claim 1 in which liquid-tight seal means are provided between said unidirectional valve means and said ram chamber comprising piston ring means operative against the wall of said ram chamber.
Claim 18
Dependent Claim
60 words
An hydraulic shock absorber according to claim 1 which is so constructed as to be operative in any position in which it may be mounted, and manually openable normally closed vent means at different locations on the body of said shock absorber so that the hydraulic liquid therein can be air-bled in every such mounted position of said shock absorber.
Claim 19
Dependent Claim
251 words
Process in energy dissipating hydraulic systems for dissipating the energy of impacting forces comprising: a. applying pressure in a single energy dissipating power stroke to hydraulic liquid in a hydraulic ram chamber via an impacting force acting in one Direction upon an hydraulic ram operating out of one end of said ram chamber; b. transferring hydraulic liquid from said ram chamber to hydraulic liquid in an hydraulic reservoir maintained under yieldable pressure; c. said transferring of hydraulic liquid being accomplished by movement of an hydraulic ram to its retracted position in said ram chamber during said power stroke by said ram progressively closing off all but the last of axially spaced orifices in said ram chamber; the first of said orifices being free flow orifices through which hydraulic liquid flows from said ram chamber to said reservoir under free flow conditions for a first part of said power stroke and the remainder of said orifices being flow restriction orifices through which hydraulic liquid flows from said ram chamber to said reservoir under flow restriction conditions for the remainder of said power stroke; said hydraulic ram being fully retracted without closing off the last of said flow restriction orifices; and d. at the end of said power stroke applying pressure to said hydraulic liquid in said ram chamber by effecting return of hydraulic liquid thereto from said reservoir under said yieldable pressure and under free flow conditions to produce a return force acting in the opposite direction in a single return stroke.
Claim 20
Dependent Claim
251 words
Process in energy dissipating hydraulic systems for dissipating the energy of impacting forces comprising: a. applying pressure in a single energy dissipating power stroke to hydraulic liquid in a hydraulic ram chamber via an impacting force acting in one Direction upon an hydraulic ram operating out of one end of said ram chamber; b. transferring hydraulic liquid from said ram chamber to hydraulic liquid in an hydraulic reservoir maintained under yieldable pressure; c. said transferring of hydraulic liquid being accomplished by movement of an hydraulic ram to its retracted position in said ram chamber during said power stroke by said ram progressively closing off all but the last of axially spaced orifices in said ram chamber; the first of said orifices being free flow orifices through which hydraulic liquid flows from said ram chamber to said reservoir under free flow conditions for a first part of said power stroke and the remainder of said orifices being flow restriction orifices through which hydraulic liquid flows from said ram chamber to said reservoir under flow restriction conditions for the remainder of said power stroke; said hydraulic ram being fully retracted without closing off the last of said flow restriction orifices; and d. at the end of said power stroke applying pressure to said hydraulic liquid in said ram chamber by effecting return of hydraulic liquid thereto from said reservoir under said yieldable pressure and under free flow conditions to produce a return force acting in the opposite direction in a single return stroke.
Claim 21
Dependent Claim
30 words
Process according to claim 20 in which said ram chamber and said reservoir are filled by transferring hydraulic liquid under pressure into said reservoir until it visibly flows out therefrom.
Claim 22
Dependent Claim
35 words
Process according to claim 20 in which a flow restricting orifice is moved relative to a cavity to alter the cushioning effect of said power stroke in accordance with the magnitude of the impacting force.
Claim 23
Dependent Claim
41 words
Process according to claim 22 in which said flow restricting orifice is rotated relative to said cavity between maximum and minimum area positions corresponding, respectively, to maximum and minimum flow of hydraulic liquid through said cavity and said flow restricting orifice.
Claim 24
Dependent Claim
26 words
Process according to claim 20 further comprising transfering heat from said hydraulic liquid to ambient air during both said power and return strokes for cooling purposes.
Claim 25
Dependent Claim
328 words
An industrial type hydraulic shock absorber having a center section and end plates bolted to said center section at opposite ends thereof, an hydraulic ram chamber defined by a cylinder fast in said center section between said end plates, an hydraulic ram operative in said ram chamber and out of one of said end plates, said ram having a single energy dissipating power stroke in respect to an impacting force acting in one direction thereon, an hydraulic reservoir defined by a chamber in said center section, a piston slidable in said reservoir and yieldable means operative upon said piston, means interconnecting said ram chamber and said reservoir so that a transfer of hydraulic liquid occurs in opposition to said yieldable means from said ram chamber to said reservoir under free flow conditions for a first part of said power stroke and under flow restriction conditions for the remainder thereof, said ram chamber provided with axially spaced orifices all but the last of which are closed off progressively by said hydraulic ram in its movement to its retracted position in said ram chamber during said power stroke. The first of said orifices being free flow orifices through which hydraulic liquid flows from said ram chamber to said reservoir under free flow conditions for a first part of said power stroke and the remainder of said orifices being flow restriction orifices through which hydraulic liquid flows from said ram chamber to said reservoir under flow restriction conditions for the remainder of said power stroke. Said hydraulic ram being fully retracted without closing off the last of said flow restriction orifices, said reservoir piston operative at the end of said power stroke to effect return of hydraulic liquid from the reservoir to the ram chamber to return the ram in the opposite direction in a singlE return stroke thereof, said interconnecting means including unidirectional valve means closed during said power stroke and open to the ram chamber during said return stroke.
Claim 26
Dependent Claim
328 words
An industrial type hydraulic shock absorber having a center section and end plates bolted to said center section at opposite ends thereof, an hydraulic ram chamber defined by a cylinder fast in said center section between said end plates, an hydraulic ram operative in said ram chamber and out of one of said end plates, said ram having a single energy dissipating power stroke in respect to an impacting force acting in one direction thereon, an hydraulic reservoir defined by a chamber in said center section, a piston slidable in said reservoir and yieldable means operative upon said piston, means interconnecting said ram chamber and said reservoir so that a transfer of hydraulic liquid occurs in opposition to said yieldable means from said ram chamber to said reservoir under free flow conditions for a first part of said power stroke and under flow restriction conditions for the remainder thereof, said ram chamber provided with axially spaced orifices all but the last of which are closed off progressively by said hydraulic ram in its movement to its retracted position in said ram chamber during said power stroke. The first of said orifices being free flow orifices through which hydraulic liquid flows from said ram chamber to said reservoir under free flow conditions for a first part of said power stroke and the remainder of said orifices being flow restriction orifices through which hydraulic liquid flows from said ram chamber to said reservoir under flow restriction conditions for the remainder of said power stroke. Said hydraulic ram being fully retracted without closing off the last of said flow restriction orifices, said reservoir piston operative at the end of said power stroke to effect return of hydraulic liquid from the reservoir to the ram chamber to return the ram in the opposite direction in a singlE return stroke thereof, said interconnecting means including unidirectional valve means closed during said power stroke and open to the ram chamber during said return stroke.
Claim 27
Dependent Claim
100 words
An hydraulic shock absorber according to claim 25 in which said ram chamber is defined by a first cylinder fast in said center section between said end plates, and further comprising an intermediate relief chamber defined by a cavity in said center section and a second cylinder concentric about and supported for rotation on said first cylinder, flow restriction means in said second cylinder providing a variable area metering orifice for flow of hydraulic liquid between said ram chamber and said intermediate relief chamber, and means for rotating said second cylinder to vary the effective area of said metering orifice.
Claim 28
Dependent Claim
26 words
An hydraulic shock absorber according to claim 26 in which resilient thrust washer means are provided between said first cylinder and one of said end plates.
Claim 29
Dependent Claim
37 words
An hydraulic shock absorber according to claim 25 in which the center section and end plates are sealed in respect to each other by gasket means comprising a metal layer sandwiched between a pair of asbestos layers.
Claim 30
Dependent Claim
34 words
An hydraulic shock absorber according to claim 25 in which each end plate is provided with mounting means by which the shock absorber can be front or rear mounted in respect to stationary structure.
References Cited (Backward Citations)
US1664486A
Cited
US3171640A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-01-11 | 1974-07-13 | 1975-01-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-01-11 | 1978-07-13 | 1979-01-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-01-11 | 1982-07-13 | 1983-01-12 | $7700.00 | Window Closed / Lapsed |