US3687227A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Control circuit and lock valve for pivot axle lockout cylinders
Assignee: NORTHWEST ENGINEERING Co A CORP OF
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Filing: 1970-11-05
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Granted: 1972-08-29
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Expires: 1990-11-05
Abstract
Abstract A control circuit for the lockout cylinders of a pivot axle excavator carrier includes a normally closed lock valve that is automatically actuated during propelling to establish open communication between the cylinders to allow pivotal axle movement. The valve includes facing check valves which are unseated by oppositely moving shuttle spools to open a bypass passage, and an actuating line for the valve is connected to a hydraulic propel motor so that the valve is opened automatically upon propelling. In the preferred embodiment, a second actuating line for the valve is connected to a hydraulic outrigger cylinder so that the valve is also actuated automatically while outriggers are being set.
Inventors
- 👤 Gottfried Reuter
- 👤 Fortunato S Ajero
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 00:21
CPC Classifications
B; B60; B60G; B60G17/00; B60G17/005; B60G2200/00; B60G2200/30; B60G2200/32; B60G2204/00; B60G2204/40; B60G2204/46
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
107 words
A control circuit for an excavator carrier or the like having a propel motor, and a pivot axle with hydraulic lockout cylinders at each end, said control circuit comprising: a connecting line between the lockout cylinders which, when open, allows fluid communication therebetween to allow pivotal movement of the axle; a normally closed lock valve in the connecting line which is actuable to open the connecting line; and actuating circuit means between the propel motor and the lock valve to automatically actuate the lock valve upon activation of the propel motor, the lock valve automatically returning to closed position when the propel motor is no longer activated.
Claim 2
Dependent Claim
107 words
A control circuit for an excavator carrier or the like having a propel motor, and a pivot axle with hydraulic lockout cylinders at each end, said control circuit comprising: a connecting line between the lockout cylinders which, when open, allows fluid communication therebetween to allow pivotal movement of the axle; a normally closed lock valve in the connecting line which is actuable to open the connecting line; and actuating circuit means between the propel motor and the lock valve to automatically actuate the lock valve upon activation of the propel motor, the lock valve automatically returning to closed position when the propel motor is no longer activated.
Claim 3
Dependent Claim
48 words
The combination of claim 1 wherein the vehicle is also provided with outrigger means and operating means therefor; and there is a second actuating circuit means between the outrigger operating means and the lock valve to actuate the lock valve automatically on activation of the outrigger operating means.
Claim 4
Dependent Claim
46 words
The combination of claim 1 wherein the propel motor is a hydraulic motor; and the lock valve is hydraulically actuable and the actuating circuit includes a hydraulic line leading from the propel motor to the lock valve which is pressurized whenever the propel motor is activated.
Claim 5
Dependent Claim
68 words
The combination of claim 3 wherein the carrier is provided with extendable outrigger means and operating means therefor; and the outrigger operating means includes a hydraulic cylinder; and there is a second actuating circuit for the lock valve which comprises a hydraulic line leading from the lock valve and communicating with that end of the outrigger operating cylinder which is pressurized when the outrigger means is being extended.
Claim 6
Dependent Claim
136 words
The combination of claim 3 wherein the lock valve includes opposite inlet passages connected to respective parts of the line leading between the lockout cylinders; facing check valves of the entry sides of the inlet passages which are spring biased to normally close the same; a spool bore in alignment with the check valves; a pair of shuttle spools in the spool bore which are adapted to be moved away from one another to engage and unseat respective check valves; an actuating inlet leading to the spool bore between the shuttle spools; and a bypass passage the ends of which face respective check valves and are adapted to communicate with respective inlet passages and which bypasses the spool bore so that fluid can flow in either direction through the valve when the check valves are unseated.
Claim 7
Dependent Claim
160 words
The combination of claim 4 wherein the lock valve includes opposite inlet passages connected to respective parts of the line leading between the lockout cylinders; facing check valves of the entry sides of the inlet passages which are spring biased to normally close the same; a spool bore in alignment with the check valves; a pair of shuttle spools in the spool bore which are adapted to be moved away from one another to engate and unseat respective check valves; an actuating inlet leading to the spool bore between the shuttle spools; a bypass passage the ends of which face respective check valves and are adapted to communicate with respective inlet passages and which bypasses the spool bore so that fluid can flow in either direction through the valve when the check valves are unseated; and the hydraulic line of the second actuating circuit leads to the bypass passage so that pressure therein can act directly on the check valves.
References Cited (Backward Citations)
US3300232A
Cited
US3191954A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-08-29 | 1976-02-28 | 1976-08-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-08-29 | 1980-02-28 | 1980-08-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-08-29 | 1984-02-28 | 1984-08-29 | $7700.00 | Window Closed / Lapsed |