US3902401A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Hydraulic flow amplifier valve
Assignee: Caterpillar Inc
•
Filing: 1974-04-08
•
Granted: 1975-09-02
•
Expires: 1994-04-08
Abstract
Abstract A hydraulic flow amplifier valve assembly for regulating fluid flow to steering jacks. A steering control valve receives fluid directly from a pump and is pilot operated by fluid from a conventional metering unit to provide amplified flow of pump fluid to the jacks. A blocker valve passes fluid from the steering valve during steering motion of the jacks and otherwise isolates the jacks to prevent fluid loss. A lock valve protects against steering wheel slippage during overpressure conditions and also permits pilot fluid provided by the metering unit to operate the steering jacks in the event of pressure failure.
Inventors
- 👤 Thomas E Allen
- 👤 Gordon W Johnson
- 👤 Richard L M Sears
- 👤 Chester L Strantz
- 👤 John B Waggoner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 00:51
CPC Classifications
F; F15; F15B; F15B13/00; F15B13/02; F15B13/022; B; B62; B62D; B62D5/00; B62D5/06; B62D5/30; B62D5/32; F15B11/00; F15B11/16; F15B11/161; F15B11/162; F15B13/04; F15B13/0416; F15B13/0417; F15B2211/00; F15B2211/30; F15B2211/305; F15B2211/30505; F15B2211/30525; F15B2211/3053; F15B2211/30535; F15B2211/3056; F15B2211/30565; F15B2211/32; F15B2211/329; F15B2211/50; F15B2211/57; F15B2211/60; F15B2211/605; F15B2211/6051; F15B2211/6054; F15B2211/6055; F15B2211/635; F15B2211/6355; F15B2211/70; F15B2211/71; F15B2211/7114; F15B2211/7128; F15B2211/75
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
288 words
A fluid system comprising a fluid motor means, a source of fluid under pressure, means defining a fluid inlet connected with the source, fluid metering means being operable to transfer liquid from said source thereacross at a rate proportional to a desired rate of operation for the fluid motor means, means for receiving fluid transferred by the metering means, a control valve means connected with said fluid inlet and said motor means, said control valve means also connected with said means for receiving fluid for response to metering fluid flow therein, said control valve means being pilot operated by said metering fluid flow to direct fluid from the inlet to the motor means at a rate proportional to said pilot flow from said metering means, pressure compensating means connected through conduit means with the control valve means and said fluid inlet, said pressure compensating means being operable to regulate fluid pressure within the fluid inlet, and blocker means to normally block fluid flow to the motor means and thus fix the operating position of the motor means, said blocker means being responsive to said pilot flow to permit passage of fluid flow to the motor means, relief means for shifting the blocker means to connect the motor means to drain in response to overpressure above a preselected level in the motor means, said control valve means and said blocker means being formed by a single valve assembly comprising a slidable spool responsive to pilot flow to communicate fluid from the inlet to a downstream conduit connected with the fluid motor means, first orifice means connecting said pilot flow to the downstream conduit and second orifice means connecting fluid flow from said single valve assembly to said downstream conduit.
Claim 2
Dependent Claim
288 words
A fluid system comprising a fluid motor means, a source of fluid under pressure, means defining a fluid inlet connected with the source, fluid metering means being operable to transfer liquid from said source thereacross at a rate proportional to a desired rate of operation for the fluid motor means, means for receiving fluid transferred by the metering means, a control valve means connected with said fluid inlet and said motor means, said control valve means also connected with said means for receiving fluid for response to metering fluid flow therein, said control valve means being pilot operated by said metering fluid flow to direct fluid from the inlet to the motor means at a rate proportional to said pilot flow from said metering means, pressure compensating means connected through conduit means with the control valve means and said fluid inlet, said pressure compensating means being operable to regulate fluid pressure within the fluid inlet, and blocker means to normally block fluid flow to the motor means and thus fix the operating position of the motor means, said blocker means being responsive to said pilot flow to permit passage of fluid flow to the motor means, relief means for shifting the blocker means to connect the motor means to drain in response to overpressure above a preselected level in the motor means, said control valve means and said blocker means being formed by a single valve assembly comprising a slidable spool responsive to pilot flow to communicate fluid from the inlet to a downstream conduit connected with the fluid motor means, first orifice means connecting said pilot flow to the downstream conduit and second orifice means connecting fluid flow from said single valve assembly to said downstream conduit.
Claim 3
Dependent Claim
85 words
The combination of claim 1 further comprising a signal pressure selector valve responsive to pilot flow and disposed between the spool of said single valve assembly and said second orifice means and a feedback pressure selector shuttle valve disposed between said signal pressure selector valve and said pressure compensating means, said two selector valves being responsive to pilot flow to connect a portion of said fluid flow from said single valve assembly between its spool and said second orifice means with said pressure compensating means.
Claim 4
Dependent Claim
34 words
The combination of claim 1 wherein the pressure drops across the first orifice means and the second orifice means are substantially equal and variable to attain said desired rate of operation of said motor.
Claim 5
Dependent Claim
281 words
A fluid system comprising a fluid motor means, a source of fluid under pressure, means defining a fluid inlet connected with said source, fluid metering means being operable to transfer fluid from said source thereacross at a rate proportional to a desired rate of operation for the fluid motor means, means for receiving fluid transferred by said metering means, a control valve means connected with said fluid inlet and said motor means, said control valve means also connected with said means for receiving for response to metering fluid flow therein, said control valve means being pilot operated by said metering fluid flow to direct fluid from the inlet to the motor means at a rate proportional to said pilot flow from said metering means, pressure compensating means connected through conduit means with said control valve means and said fluid inlet, said pressure compensating means being operable to regulate fluid pressure within the fluid inlet, and blocker means to normally block fluid flow to the motor means and thus fix its operating position, said Blocker means being responsive to said pilot flow to permit passage of fluid flow to the motor means, relief means for shifting the blocker means to connect the motor means to drain in response to overpressure above a preselected level within the motor means, said control valve means and said blocker means being provided by a single valve assembly comprising a slidable spool responsive to pilot flow to communicate fluid from the inlet to a downstream conduit connected with the fluid motor means, orifice means receiving fluid from said inlet, said orifice means directing inlet fluid from said spool in said single valve assembly to said downstream conduit.
Claim 6
Dependent Claim
281 words
A fluid system comprising a fluid motor means, a source of fluid under pressure, means defining a fluid inlet connected with said source, fluid metering means being operable to transfer fluid from said source thereacross at a rate proportional to a desired rate of operation for the fluid motor means, means for receiving fluid transferred by said metering means, a control valve means connected with said fluid inlet and said motor means, said control valve means also connected with said means for receiving for response to metering fluid flow therein, said control valve means being pilot operated by said metering fluid flow to direct fluid from the inlet to the motor means at a rate proportional to said pilot flow from said metering means, pressure compensating means connected through conduit means with said control valve means and said fluid inlet, said pressure compensating means being operable to regulate fluid pressure within the fluid inlet, and blocker means to normally block fluid flow to the motor means and thus fix its operating position, said Blocker means being responsive to said pilot flow to permit passage of fluid flow to the motor means, relief means for shifting the blocker means to connect the motor means to drain in response to overpressure above a preselected level within the motor means, said control valve means and said blocker means being provided by a single valve assembly comprising a slidable spool responsive to pilot flow to communicate fluid from the inlet to a downstream conduit connected with the fluid motor means, orifice means receiving fluid from said inlet, said orifice means directing inlet fluid from said spool in said single valve assembly to said downstream conduit.
Claim 7
Dependent Claim
83 words
The combination of claim 4 further comprising a signal pressure selector valve responsive to pilot flow and disposed between the spool of said single valve assembly and said orifice means and a feedback pressure selector shuttle valve disposed between said signal pressure selector valve and said pressure compensating means, said two selector valves being responsive to pilot flow to connect a portion of said fluid flow from said single valve assembly between its spool and said orifice means with said pressure compensating means.
References Cited (Backward Citations)
US3234957A
Cited
US3260325A
Cited
US3411416A
Cited
US3347041A
Cited
US3739690A
Cited
US3827453A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-09-01 | 1979-03-03 | 1979-09-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-09-01 | 1983-03-03 | 1983-09-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-09-01 | 1987-03-03 | 1987-09-02 | $7700.00 | Window Closed / Lapsed |