Patent US2980964A successfully refreshed from Google Patents.
Patent US3574418A successfully refreshed from Google Patents.
US3574418A
Expired / Lapsed
US
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Shock absorber for endless-track-type tractors and the like
Assignee: Hitachi Ltd
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Filing: 1969-02-07
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Granted: 1971-04-13
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Expires: 1989-02-07
Abstract
Abstract A shock absorber for the endless track of a vehicle providing three oil cylinders, namely, an actuating cylinder responsive to shock motion, a shock-absorbing cylinder and a tension-adjusting cylinder and means for controlling the flow of fluid to these cylinders so that when any shock motion is applied to the actuating cylinder, the oil within the oil-filled chamber of the cylinder is forced to flow into the shock-absorbing cylinder, whereby the shock motion can be absorbed; whereas, if the endless track becomes loose, the oil within the oil-filled chamber of the tension-adjusting cylinder is forced to flow into the oil-filled chamber of the actuating cylinder, whereby the tension of the endless track belt can be recovered.
Inventors
- 👤 Nobuya Okabe
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 14:37
CPC Classifications
B; B62; B62D; B62D55/00; B62D55/08; B62D55/30; F; F16; F16F; F16F9/00; F16F9/10; F16F9/14; F16F9/16; F16F9/22; F16H; F16H7/00; F16H7/08; F16H2007/0802; F16H2007/0806; F16H2007/0812; F16H7/0848; F16H2007/0859
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
236 words
A shock absorber for endless-track-type tractors and the like including means for keeping the tension of an endless track belt at a constant value, which comprises: a first oil cylinder including a first piston, a piston rod, and a first oil-filled chamber formed on one side of said first piston; a second oil cylinder for shock absorption including a second piston, a second oil-filled chamber formed on one side of said second piston, and a shock-absorbing spring arranged within the cylinder between said second piston and the wall thereof so as to apply pressure to the oil within the second oil-filled chamber by way of the second piston; a third oil cylinder for tension adjustment including a third piston, a third oil-filled chamber formed on one side of said third piston, and a tension-adjusting spring arranged within the cylinder between said third piston and the wall thereof so as to apply pressure to the oil within the third oil-filled chamber by way of the third piston; a first oil-passage means connecting the oil-filled chambers of said first and second cylinders; a second oil-passage means connecting the oil-filled chamber of said first and third cylinders; means for prohibiting oil-flow from the first oil-filled chamber to the third oil-filled cHamber in response to shock pressures applied to the first oil-filled chamber by way of the first piston; and means for manually adjusting the strength of said tensionadjusting spring.
Claim 2
Dependent Claim
236 words
A shock absorber for endless-track-type tractors and the like including means for keeping the tension of an endless track belt at a constant value, which comprises: a first oil cylinder including a first piston, a piston rod, and a first oil-filled chamber formed on one side of said first piston; a second oil cylinder for shock absorption including a second piston, a second oil-filled chamber formed on one side of said second piston, and a shock-absorbing spring arranged within the cylinder between said second piston and the wall thereof so as to apply pressure to the oil within the second oil-filled chamber by way of the second piston; a third oil cylinder for tension adjustment including a third piston, a third oil-filled chamber formed on one side of said third piston, and a tension-adjusting spring arranged within the cylinder between said third piston and the wall thereof so as to apply pressure to the oil within the third oil-filled chamber by way of the third piston; a first oil-passage means connecting the oil-filled chambers of said first and second cylinders; a second oil-passage means connecting the oil-filled chamber of said first and third cylinders; means for prohibiting oil-flow from the first oil-filled chamber to the third oil-filled cHamber in response to shock pressures applied to the first oil-filled chamber by way of the first piston; and means for manually adjusting the strength of said tensionadjusting spring.
Claim 3
Dependent Claim
15 words
A shock absorber according to claim 1, wherein said prohibiting means comprises a nonreturn valve.
Claim 4
Dependent Claim
27 words
A shock absorber according to claim 1, wherein said prohibiting means comprises a sufficiently narrow passage to effectively prevent fluid flow therethrough in response to transient pressures.
Claim 5
Dependent Claim
34 words
A shock absorber according to claim 1, wherein the effective strength of the shock-absorbing spring within said second cylinder is selected to be larger than that of the tension-adjusting spring within said third cylinder.
Claim 6
Dependent Claim
30 words
A shock absorber according to claim 1, wherein said adjusting means comprises a cap screwed into the outer end portion of said inner cylinder member to receive said tension-adjusting spring.
Claim 7
Dependent Claim
252 words
A shock absorber for endless-track-type tractors and the like including means for keeping the tension of an endless track belt at a constant value, which comprises: an outer cylinder member; an inner cylinder member coaxially fixed within said outer cylinder member with one end terminating within said outer cylinder; a partition member formed at said one end portion of said inner cylinder and extending to the inner wall of said outer cylinder to divide the outer cylinder member into first and second cylinder chambers; a first piston located within said first cylinder chamber; a piston rod for actuating said first piston; a second piston having a ringlike shape located within said second cylinder chamber so as to slide on the outer surface of said inner cylinder member; a shock-absorbing spring located within said second cylinder chamber so as to push said second piston toward said partition member; a third piston located within said inner cylinder member; a tension-adjusting spring located within the inner cylinder member so as to push said third piston toward said partition member; first oil-passage means formed through said partition member to connect both of said first and second cylinder chambers; second oil-passage means formed through said partition member to connect both said first cylinder chamber and said inner cylinder member; means for prohibiting the oil-flow from said first cylinder chamber to said inner cylinder member when the former oil-filled chamber is suddenly pressured by said first piston; and means for manually adjusting the strength of said tension-adjusting spring.
Claim 8
Dependent Claim
252 words
A shock absorber for endless-track-type tractors and the like including means for keeping the tension of an endless track belt at a constant value, which comprises: an outer cylinder member; an inner cylinder member coaxially fixed within said outer cylinder member with one end terminating within said outer cylinder; a partition member formed at said one end portion of said inner cylinder and extending to the inner wall of said outer cylinder to divide the outer cylinder member into first and second cylinder chambers; a first piston located within said first cylinder chamber; a piston rod for actuating said first piston; a second piston having a ringlike shape located within said second cylinder chamber so as to slide on the outer surface of said inner cylinder member; a shock-absorbing spring located within said second cylinder chamber so as to push said second piston toward said partition member; a third piston located within said inner cylinder member; a tension-adjusting spring located within the inner cylinder member so as to push said third piston toward said partition member; first oil-passage means formed through said partition member to connect both of said first and second cylinder chambers; second oil-passage means formed through said partition member to connect both said first cylinder chamber and said inner cylinder member; means for prohibiting the oil-flow from said first cylinder chamber to said inner cylinder member when the former oil-filled chamber is suddenly pressured by said first piston; and means for manually adjusting the strength of said tension-adjusting spring.
Claim 9
Dependent Claim
30 words
A shock absorber according to claim 6, wherein said adjusting means comprises a cap screwed into the outer end portion of said inner cylinder member to receive said tension-adjusting spring.
Claim 10
Dependent Claim
15 words
A shock absorber according to claim 6, wherein said prohibiting means comprises a nonreturn valve.
Claim 11
Dependent Claim
27 words
A shock absorber according to claim 6, wherein said prohibiting means comprises a sufficiently narrow passage to effectively prevent fluid flow therethrough in response to transient pressures.
Claim 12
Dependent Claim
34 words
A shock absorber according to claim 6, wherein the effective strength of the shock-absorbing spring within said second cylinder chamber is selected larger than that of the tension-adjusting spring within said inner cylinder member.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-04-12 | 1974-10-12 | 1975-04-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-04-12 | 1978-10-12 | 1979-04-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-04-12 | 1982-10-12 | 1983-04-13 | $7700.00 | Window Closed / Lapsed |