US4078681A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Dual pump hydraulic control system with predetermined flow crossover provision
Assignee: Caterpillar Inc
•
Filing: 1976-08-24
•
Granted: 1978-03-14
•
Expires: 1996-08-24
Abstract
Abstract A dual pump hydraulic control system with a predetermined flow crossover provision is disclosed including a first hydraulic control circuit having a first source of fluid pressure, a first motor, a first distributor valve in communication with the first source and moveable into an actuating condition for directing fluid to the first motor, a second motor, a second distributor valve in interrupted series communication with the first distributor valve and moveable into an actuating condition for directing fluid to the second motor; a second hydraulic control circuit having a second source of fluid pressure, a third motor, a third distributor valve in communication with the second source for directing fluid to the third motor; and a crossover valve and resolver network responsive to the actuating condition of the first distributor valve and to the actuating condition of the second distributor valve for communicating fluid from the second source to the second motor to supplement fluid from the first source to the second motor while preventing full fluid flow from both the first and second sources thereto. Such hydraulic system is particularly adapted to simultaneous swing and stick-in movement of a hydraulic excavator.
Inventors
- 👤 Jesse L. Field, Jr.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 20:35
CPC Classifications
B; B62; B62D; B62D11/00; B62D11/02; B62D11/06; B62D11/10; B62D11/14; B62D11/18; E; E02; E02F; E02F9/00; E02F9/20; E02F9/22; E02F9/2221; E02F9/2239; E02F9/2278; E02F9/2292; E02F9/2296; F; F15; F15B; F15B11/00; F15B11/16; F15B11/17; F15B2211/00; F15B2211/20; F15B2211/205; F15B2211/2053; F15B2211/20546; F15B2211/20576; F15B2211/30; F15B2211/305; F15B2211/30505; F15B2211/31; F15B2211/3105; F15B2211/3116; F15B2211/32; F15B2211/329; F15B2211/40; F15B2211/405; F15B2211/40515; F15B2211/415; F15B2211/41554; F15B2211/42; F15B2211/428; F15B2211/46; F15B2211/60; F15B2211/635; F15B2211/6355; F15B2211/67; F15B2211/70; F15B2211/71; F15B2211/7142
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
164 words
A dual pump hydraulic control system with predetermined flow crossover provision, comprising: a first hydraulic control circuit including a first source of fluid pressure, a first motor, a first distributor valve in communication with said first source and having an actuating condition for directing fluid to said first motor, a second motor, a second distributor valve in interrupted series communication with said first distributor valve and having an actuating condition for directing remaining fluid from said first source to said second motor; a second hydraulic control circuit including a second source of fluid pressure, a third motor, a third distributor valve in communication with said second source for direction fluid to said third motor; and crossover valve means including a spring-biased, two position valve automatically responsive to said actuating condition to said first distributor valve and to said actuating condition of said second distributor valve for communicating fluid from said second source to said second motor while preventing full flow from both sources thereto.
Claim 2
Dependent Claim
164 words
A dual pump hydraulic control system with predetermined flow crossover provision, comprising: a first hydraulic control circuit including a first source of fluid pressure, a first motor, a first distributor valve in communication with said first source and having an actuating condition for directing fluid to said first motor, a second motor, a second distributor valve in interrupted series communication with said first distributor valve and having an actuating condition for directing remaining fluid from said first source to said second motor; a second hydraulic control circuit including a second source of fluid pressure, a third motor, a third distributor valve in communication with said second source for direction fluid to said third motor; and crossover valve means including a spring-biased, two position valve automatically responsive to said actuating condition to said first distributor valve and to said actuating condition of said second distributor valve for communicating fluid from said second source to said second motor while preventing full flow from both sources thereto.
Claim 3
Dependent Claim
37 words
The control system of claim 1 including an outlet conduit from said third distributor valve, and wherein said crossover valve means includes a crossover line which communicates flow in said outlet conduit to said second distributor valve.
Claim 4
Dependent Claim
93 words
The control system of claim 2 including pilot control valve means for remotely positioning said distributor valves and including a pair of signal lines communicating with the opposite ends of said first distributor valve and effective at a predetermined pressure level for moving it from a central open-centered condition to direct fluid to said first motor, said crossover valve means being responsive to a drop in pressure below said pressure level in either of said signal lines for preventing fluid flow from both said first and second sources to said second distributor valve.
Claim 5
Dependent Claim
202 words
An improved dual pump hydraulic control system of the type having a first control circuit including a first fluid pressure source, a first motor, a first distributor valve in communication with said first source for selectively directing fluid to said first motor, a second motor, a second distributor valve in interrupted downstream series communication with said first distributor valve for selectively directing fluid to said second motor, a second fluid pressure source, a third motor, a third distributor valve in communication with said second source for selectively directing fluid to said third motor, a depressurized outlet line leading from said third distributor valve, a blocker valve associated with said outlet line, a crossover line between said outlet line and said second distributor valve, wherein the improvement comprises: resolver network means including a two-position selector valve and shuttle valve means responsive to either direction of actuation of said first distributor valve for preconditioning said selector valve, moving said blocker valve into a position blocking said outlet line and communicating fluid flow from said second source through said crossover line to said second distributor valve and to said second motor for supplementing excess flow from said first source and said first distributor valve thereto.
Claim 6
Dependent Claim
202 words
An improved dual pump hydraulic control system of the type having a first control circuit including a first fluid pressure source, a first motor, a first distributor valve in communication with said first source for selectively directing fluid to said first motor, a second motor, a second distributor valve in interrupted downstream series communication with said first distributor valve for selectively directing fluid to said second motor, a second fluid pressure source, a third motor, a third distributor valve in communication with said second source for selectively directing fluid to said third motor, a depressurized outlet line leading from said third distributor valve, a blocker valve associated with said outlet line, a crossover line between said outlet line and said second distributor valve, wherein the improvement comprises: resolver network means including a two-position selector valve and shuttle valve means responsive to either direction of actuation of said first distributor valve for preconditioning said selector valve, moving said blocker valve into a position blocking said outlet line and communicating fluid flow from said second source through said crossover line to said second distributor valve and to said second motor for supplementing excess flow from said first source and said first distributor valve thereto.
Claim 7
Dependent Claim
153 words
A hydraulic control system for an excavator having a rotatable superstructure, a boom pivotally mounted on the superstructure, a stick mounted on the boom, and a bucket mounted on the stick, the system comprising: a first source of fluid pressure; a second source of fluid pressure; a swing motor for controlling movement of said super-structure; a stick control motor; a bucket control motor; first distributor valve means for initially connecting said first source to said swing motor and then in interrupted series connecting said first source to said stick control motor; second distributor valve mens for connecting said second source to said bucket control motor; and crossover valve means for communicating fluid from said second source to said stick control motor in response to actuation of said swing motor and to actuation of said stick control motor solely in one direction of movement thereof while preventing full flow from both of said sources.
Claim 8
Dependent Claim
153 words
A hydraulic control system for an excavator having a rotatable superstructure, a boom pivotally mounted on the superstructure, a stick mounted on the boom, and a bucket mounted on the stick, the system comprising: a first source of fluid pressure; a second source of fluid pressure; a swing motor for controlling movement of said super-structure; a stick control motor; a bucket control motor; first distributor valve means for initially connecting said first source to said swing motor and then in interrupted series connecting said first source to said stick control motor; second distributor valve mens for connecting said second source to said bucket control motor; and crossover valve means for communicating fluid from said second source to said stick control motor in response to actuation of said swing motor and to actuation of said stick control motor solely in one direction of movement thereof while preventing full flow from both of said sources.
Claim 9
Dependent Claim
61 words
The control system of claim 5 including an outlet line from said second distributor valve means, and wherein said crossover valve means includes a blocker valve disposed in said outlet line and a resolver network responsive to position said blocker valve in a crossover mode of operation only when said first distributor valve means is supplying fluid to said swing motor.
Claim 10
Dependent Claim
36 words
The control system of claim 6 wherein said resolver network includes selector valve means for permitting full flow of fluid from both of said sources to said stick control motor in said one direction of movement.
Claim 11
Dependent Claim
67 words
The control system of claim 7 including a boom control motor, and wherein said second distributor valve means also connects said second source to said boom control motor in interrupted subservient series to said bucket control motor, said crossover means and said selector means also permitting full flow of fluid from both of said sources to said boom control motor in at least one direction of movement.
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 |