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US3604205A Expired / Lapsed US ⏱️ 0.0 years remaining

Hydraulic fluid circuit

Assignee: Caterpillar Inc
•
Filing: 1969-06-19
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Granted: 1971-09-14
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Expires: 1989-06-19
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Abstract

Abstract A hydraulic circuit having one or more pumps adjacent motor means in a machine with hydraulic motors which are supplied by the circuit being located in a relatively remote location from the pumps. A control valve is associated with each hydraulic motor and includes a return line in communication with a first hydraulic fluid tank. An assembly of one or more pumps for delivering fluid under pressure to the control valves is located adjacent the motor means and is driven by the motor means. A second hydraulic fluid tank is associated with the pump assembly, the second tank providing fluid to the pumps and being in communication with the first tank by a return conduit for delivering fluid from the first tank to the second tank. To prevent rupture of the first tank, a baffle is preferably arranged within that tank to assure a constant air pocket above the fluid.

Inventors

  • 👤 Thomas H Geselbracht
  • 👤 David S Vinton

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-25 06:47
CPC Classifications
F; F15; F15B; F15B1/00; F15B1/26; F15B1/265; Y; Y10; Y10T; Y10T137/00; Y10T137/2931; Y10T137/3115; Y10T137/3118

Claims Analysis

Total Claims: 12
Claim 1
Independent Claim 163 words
A hydraulic circuit for a machine having a motor means and a hydraulic motor remotely located from the motor means of the machine, comprising at least one hydraulic pump associated in driven relation with the motor means a control valve associated with the hydraulic motor, said control valve being in communication with a fluid outlet conduit of said pump, said control valve being selectively operable to deliver fluid under pressure for operating the motor, a first hydraulic fluid tank associated with said control valve, said first tank being in communication with a fluid return from said valve, a second hydraulic fluid tank associated with said pump, said second tank being in communication with an inlet conduit to said pump, and a return conduit providing substantially free communication between said first and second tanks for delivering hydraulic fluid from said first tank to said second tank, said return conduit including a stand pipe in said first tank for establishing a normal fluid level therein.
Claim 2
Dependent Claim 163 words
A hydraulic circuit for a machine having a motor means and a hydraulic motor remotely located from the motor means of the machine, comprising at least one hydraulic pump associated in driven relation with the motor means a control valve associated with the hydraulic motor, said control valve being in communication with a fluid outlet conduit of said pump, said control valve being selectively operable to deliver fluid under pressure for operating the motor, a first hydraulic fluid tank associated with said control valve, said first tank being in communication with a fluid return from said valve, a second hydraulic fluid tank associated with said pump, said second tank being in communication with an inlet conduit to said pump, and a return conduit providing substantially free communication between said first and second tanks for delivering hydraulic fluid from said first tank to said second tank, said return conduit including a stand pipe in said first tank for establishing a normal fluid level therein.
Claim 3
Dependent Claim 27 words
The invention of claim 1 wherein said control valve is of a type for immersion in hydraulic fluid and said valve is disposed within said first tank.
Claim 4
Dependent Claim 47 words
The invention of claim 1 wherein the machine includes a plurality of the hydraulic motors and further comprising one of said control valves associated with each hydraulic motor. 4 The invention of claim 3 further comprising a plurality of said pumps respectively associated with said control valves.
Claim 5
Dependent Claim 37 words
The invention of claim 3 wherein said control valves are of a type suitable for immersion in hydraulic fluid, said control valves being arranged in generally horizontal relation within said first tank generally adjacent the bottom thereof.
Claim 6
Dependent Claim 33 words
The invention of claim 1 wherein said two tanks are relatively disposed upon the machine so that the fluid level is normally somewhat higher in said first tank than in said second tank.
Claim 7
Dependent Claim 18 words
The invention of claim 1 wherein the machine is a vehicle and the motor means is its engine.
Claim 8
Dependent Claim 31 words
The invention of claim 1 wherein baffle means are secured to a generally continuous portion of said first tank for maintaining an air pocket at the top of said first tank.
Claim 9
Dependent Claim 31 words
The invention of claim 8 wherein a removable cover is arranged atop said first tank and said baffle means is a cylindrical member secured to the cover and extending downwardly therefrom.
Claim 10
Dependent Claim 155 words
A hydraulic circuit for a vehicle having motor means, at least one implement and a hydraulic motor for operating the implement being remotely located from the motor means, comprising a hydraulic pump associated with and coupled in driven relation to the motor means, a control valve hydrauLically associated with the hydraulic motor, said control valve being in communication with said pump by a high-pressure fluid conduit, a first hydraulic fluid tank associated with said control valve, said first tank being in communication with a fluid return line from said valve, a second hydraulic fluid tank associated with said pump, said second tank being in communication with an inlet conduit for delivering hydraulic fluid to said pump, and a return conduit substantially freely communicating said two tanks for delivering fluid from said first tank to said second tank, said return conduit including a stand pipe in said first tank for establishing a normal fluid level therein.
Claim 11
Dependent Claim 155 words
A hydraulic circuit for a vehicle having motor means, at least one implement and a hydraulic motor for operating the implement being remotely located from the motor means, comprising a hydraulic pump associated with and coupled in driven relation to the motor means, a control valve hydrauLically associated with the hydraulic motor, said control valve being in communication with said pump by a high-pressure fluid conduit, a first hydraulic fluid tank associated with said control valve, said first tank being in communication with a fluid return line from said valve, a second hydraulic fluid tank associated with said pump, said second tank being in communication with an inlet conduit for delivering hydraulic fluid to said pump, and a return conduit substantially freely communicating said two tanks for delivering fluid from said first tank to said second tank, said return conduit including a stand pipe in said first tank for establishing a normal fluid level therein.
Claim 12
Dependent Claim 49 words
The invention of claim 10 wherein the vehicle includes a plurality of the hydraulic motors, a plurality of control valves being respectively associated with the hydraulic motors and arranged in generally horizontal relation within said first tank, a plurality of said pump being in respective communication with said valves.

References Cited (Backward Citations)

US3234855A Cited
US3222865A Cited
US3222866A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1974-09-13 1975-03-15 1975-09-14 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1978-09-13 1979-03-15 1979-09-14 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1982-09-13 1983-03-15 1983-09-14 $7700.00 Window Closed / Lapsed

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