US3734129A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Hydraulic control valve
Assignee: Massey Ferguson Inc
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Filing: 1971-05-20
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Granted: 1973-05-22
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Expires: 1991-05-20
Abstract
Abstract A hydraulic directional valve system which may be used for controlling motor cylinders associated with a tractor or the like has paired sliding spool valves operated in opposite directions by a walking beam lever to control connection of an inlet and an outlet with either of a pair of motor ports. Slow rates of feed are obtained by metering the flow out of the motor port, whether induced by pump pressure or gravity. For this purpose, a pilot operated metering-out valve has its pilot controlled by the main spool to provide first a series of gradually increasing small openings and during final movement of the spool to cause instantaneous opening of a large pilot operated metering-out valve which opens in a direction opposite to the movement of the main spool. The system includes a pilot operated pressure relief valve which provides unloading of the supply pressure when all directional valves are in neutral, which provides also hydraulic detent release for the main spool during slow metering and when pressure builds up at the end of a motor stroke and which further provides overload relief at a still higher maximum pressure.
Inventors
- 👤 Dest J Van
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 06:59
CPC Classifications
F; F16; F16K; F16K11/00; F16K11/02; F16K11/06; F16K11/065; F16K11/07; F15; F15B; F15B11/00; F15B11/02; F15B11/04; F15B11/16; F15B13/00; F15B13/02; F15B13/04; F15B13/0401; F15B13/0402; F15B13/0405; F15B2211/00; F15B2211/20; F15B2211/205; F15B2211/2053; F15B2211/20538; F15B2211/30; F15B2211/305; F15B2211/30525; F15B2211/3056; F15B2211/30565; F15B2211/32; F15B2211/321; F15B2211/324; F15B2211/35; F15B2211/351; F15B2211/353; F15B2211/50; F15B2211/505; F15B2211/50509; F15B2211/50518; F15B2211/55; F15B2211/70; F15B2211/705; F15B2211/7051; F15B2211/7053; F15B2211/75; Y; Y10; Y10T; Y10T137/00; Y10T137/8593; Y10T137/87169; Y10T137/87233; Y10T137/87241
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
122 words
A hydraulic directional valve system comprising a body having a pair of spool-receiving bores, each with lateral ports for inlet and for outlet, with an axial port for flow to and from a motor and with a third lateral port connected by a one-way passage with the axial port; pair of main spools slidable in the bores to control flow between the lateral ports, operating means to shift the spools simultaneously in opposite directions, a seat in each axial port, a poppet coaxial with each spool and biased toward the seat by a spring and by pressure in the axial port, and means controlled by the main spool for moving the poppet in a direction opposite to motion of the main spool.
Claim 2
Dependent Claim
122 words
A hydraulic directional valve system comprising a body having a pair of spool-receiving bores, each with lateral ports for inlet and for outlet, with an axial port for flow to and from a motor and with a third lateral port connected by a one-way passage with the axial port; pair of main spools slidable in the bores to control flow between the lateral ports, operating means to shift the spools simultaneously in opposite directions, a seat in each axial port, a poppet coaxial with each spool and biased toward the seat by a spring and by pressure in the axial port, and means controlled by the main spool for moving the poppet in a direction opposite to motion of the main spool.
Claim 3
Dependent Claim
24 words
A valve system as defined in claim 1 wherein the last means includes a pilot valve controlling the pressure balance of the poppet valve.
Claim 4
Dependent Claim
33 words
A valve system as defined in claim 2 wherein the poppet valve includes an orifice therethrough and a pilot valve controlled by the main spool for restricting the orifice to unbalance the poppet.
Claim 5
Dependent Claim
164 words
A hydraulic directional valve system comprising a body having a pair of spool-receiving bores, each with a lateral port for inlet and for outlet, with an axial port for flow to aNd from a motor and with a third lateral port connected by a one-way passage with the axial port, a pair of main spools slidable in the bores to control flow between the lateral ports, operating means to shift the spools simultaneously in opposite directions, a seat in each axial port, a poppet coaxial with each spool and biased toward the seat by a spring and by pressure in the axial port, an oppositely facing smaller seat between each spool and its poppet, and a pilot valve normally closing the smaller seat and arranged to be progressively opened by motion of the main spool for metered flow out of the axial port and means on the pilot valve for rapidly opening the poppet after a further increment of motion of the main spool.
Claim 6
Dependent Claim
164 words
A hydraulic directional valve system comprising a body having a pair of spool-receiving bores, each with a lateral port for inlet and for outlet, with an axial port for flow to aNd from a motor and with a third lateral port connected by a one-way passage with the axial port, a pair of main spools slidable in the bores to control flow between the lateral ports, operating means to shift the spools simultaneously in opposite directions, a seat in each axial port, a poppet coaxial with each spool and biased toward the seat by a spring and by pressure in the axial port, an oppositely facing smaller seat between each spool and its poppet, and a pilot valve normally closing the smaller seat and arranged to be progressively opened by motion of the main spool for metered flow out of the axial port and means on the pilot valve for rapidly opening the poppet after a further increment of motion of the main spool.
Claim 7
Dependent Claim
52 words
A valve system as defined in claim 4 wherein the poppet has an axial orifice larger than the maximum orifice between the pilot valve and the smaller seat, and the pilot valve includes a pin for restricting the orifice in the poppet upon said further increment of motion of the main spool.
Claim 8
Dependent Claim
27 words
A valve system as defined in claim 5 wherein a common spring biases both the poppet and the pilot valve toward the large and small seats respectively.
Claim 9
Dependent Claim
36 words
A valve system as defined in claim 1 wherein the last means is rendered ineffective until a substantial pressure is built up in the inlet port thereby to prevent motor over-run under the action of gravity.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-05-21 | 1976-11-20 | 1977-05-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-05-21 | 1980-11-20 | 1981-05-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-05-21 | 1984-11-20 | 1985-05-22 | $7700.00 | Window Closed / Lapsed |