US4244389A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Flow control valve
Assignee: JIDOSHAKIKI CO Ltd
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Filing: 1979-04-05
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Granted: 1981-01-13
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Expires: 1999-04-05
Abstract
Abstract A flow control valve in which the hydraulic pressure difference exerted on a spool valve is controlled by regulating the degree of throttling of a variable orifice and the oil which is discharged from an oil pump is partly returned to the suction side of the oil pump in response to the degree of actuation of the spool valve according to the above hydraulic pressure difference, thereby controlling the quantity of oil that is fed to hydraulic devices. The flow passage to communicate the oil pump with the hydraulic devices includes a flow passage which permits the hydraulic oil to pass through a hole in which the spool valve is fitted, and a variable orifice is composed of an opening of the flow passage into the hole and a small diameter portion formed on the spool valve. The throttling of the variable orifice is attained by covering the opening with a predetermined clearance by the above small diameter portion.
Inventors
- 👤 Yoshiyuki Shimoura
- 👤 Asaji Kuroda
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 07:52
CPC Classifications
B; B62; B62D; B62D6/00; Y; Y10; Y10T; Y10T137/00; Y10T137/2496; Y10T137/2559; Y10T137/2574; Y10T137/2579; Y10T137/2582; Y10T137/2584
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
318 words
A flow control valve, comprising: a housing having an elongated hole therein, an inlet port extending laterally from said hole between the longitudinal ends thereof and adapted to be connected to a supply of pressure fluid, an outlet port extending laterally from said hole and adapted to be connected to a load device, said outlet port being located relative to said inlet port so that the pressure fluid can flow from said inlet port through said hole to said outlet port, said housing having a bypass port extending laterally from said hole and adapted to be connected to return pressure fluid to said supply, said bypass port being longitudinally offset from said inlet port and said outlet port, said housing having a first passage extending from said inlet port to one longitudinal end of said hole adjacent said bypass port and a second passage extending from said outlet port to the opposite longitudinal end of said hole; a spool valve slidably disposed in said hole for longitudinal movement therein, said spool valve having first, second and third valve lands slidably and sealingly engaging the wall of said hole, said first valve land being disposed between said first passage and said bypass port and being movable across said bypass port to open or close same, said third valve land being disposed between said inlet and outlet ports and said opposite longitudinal end of said hole, said second valve land being disposed between said bypass port and said inlet and outlet ports, said second valve land including a portion of reduced diameter spaced from the wall of said hole and adapted to be moved in said hole between said inlet and outlet ports to form a predetermined clearance defining a variable flow passage in said hole and extending between said inlet port and said outlet port when said valve spool is moved toward said opposite longitudinal end of said hole.
Claim 2
Dependent Claim
318 words
A flow control valve, comprising: a housing having an elongated hole therein, an inlet port extending laterally from said hole between the longitudinal ends thereof and adapted to be connected to a supply of pressure fluid, an outlet port extending laterally from said hole and adapted to be connected to a load device, said outlet port being located relative to said inlet port so that the pressure fluid can flow from said inlet port through said hole to said outlet port, said housing having a bypass port extending laterally from said hole and adapted to be connected to return pressure fluid to said supply, said bypass port being longitudinally offset from said inlet port and said outlet port, said housing having a first passage extending from said inlet port to one longitudinal end of said hole adjacent said bypass port and a second passage extending from said outlet port to the opposite longitudinal end of said hole; a spool valve slidably disposed in said hole for longitudinal movement therein, said spool valve having first, second and third valve lands slidably and sealingly engaging the wall of said hole, said first valve land being disposed between said first passage and said bypass port and being movable across said bypass port to open or close same, said third valve land being disposed between said inlet and outlet ports and said opposite longitudinal end of said hole, said second valve land being disposed between said bypass port and said inlet and outlet ports, said second valve land including a portion of reduced diameter spaced from the wall of said hole and adapted to be moved in said hole between said inlet and outlet ports to form a predetermined clearance defining a variable flow passage in said hole and extending between said inlet port and said outlet port when said valve spool is moved toward said opposite longitudinal end of said hole.
Claim 3
Dependent Claim
25 words
The flow control valve as claimed in claim 1, wherein said portion of reduced diameter is composed of a cylindrical surface having a uniform diameter.
Claim 4
Dependent Claim
43 words
The flow control valve as claimed in claim 1, wherein said portion of reduced diameter is provided with stepped surfaces or surfaces of non-uniform diameter which vary said clearance when said spool valve is moved toward said opposite longitudinal end of said hole.
Claim 5
Dependent Claim
26 words
The flow control valve as claimed in claim 3, wherein said portion of reduced diameter is provided with a plurality of cylindrical surfaces of different diameters.
Claim 6
Dependent Claim
23 words
The flow control valve as claimed in claim 3, wherein said portion of reduced diameter is provided with one or more conical surfaces.
Claim 7
Dependent Claim
23 words
The flow control valve as claimed in claim 5, wherein said portion of reduced diameter is provided with one or more cylindrical surfaces.
Claim 8
Dependent Claim
32 words
The flow control valve as claimed in claim 5 or claim 6, wherein the diameter of said conical surface progressively decreases in a direction toward said opposite longitudinal end of said hole.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-01-13 | 1984-07-14 | 1985-01-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-01-13 | 1988-07-14 | 1989-01-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-01-13 | 1992-07-14 | 1993-01-13 | $7700.00 | Window Closed / Lapsed |