Patent US4712531A successfully refreshed from Google Patents.
US3580286A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Spool valve
Assignee: Stewart Warner Corp
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Filing: 1969-04-04
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Granted: 1971-05-25
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Expires: 1989-04-04
Abstract
Abstract A unitary sleeve member formed of a nylon-molybdenum disulfide composition is fixedly carried in concentric fashion intermediate of the valve casing and a reciprocating valve spool and in contact with the peripheral surface of the valve spool.
Inventors
- 👤 Sidney D Bash
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 11:47
CPC Classifications
F; F16; F16K; F16K11/00; F16K11/02; F16K11/06; F16K11/065; F16K11/07; F16K11/0716; F15; F15B; F15B13/00; F15B13/02; F15B13/04; Y; Y10; Y10T; Y10T137/00; Y10T137/8593; Y10T137/86493; Y10T137/86574; Y10T137/8667; Y10T137/86694; Y10T137/86702
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
329 words
In a spool valve including a valve casing having means defining a longitudinally extending internal fluid cavity, a plurality of longitudinally spaced fluid ports carried by said casing and opening up into said cavity with two of said ports being load ports longitudinally spaced on respective opposite sides of a pressure port, a cylindrical spool coaxially positioned within said casing cavity for reciprocating movement along said casing axis, the improvement comprising: a sleeve assembly fixedly positioned within said casing and concentrically positioned between said spool and said casing internal wall with said sleeve assembly having at least a spool contact surface formed of a nylon-molybdenum disulfide composition, a unitary sleeve member formed entirely of nylon-molybdenum disulfide composition having a plurality of longitudinally spaced circumferential grooves in the outer periphery of said sleeve membEr each communicating with a respective one of said longitudinally spaced fluid pressure and load ports, said sleeve member having a series of circumferentially spaced, radial holes for said pressure port and a plurality of longitudinally spaced series of circumferentially spaced radial holes for each load port with each radial hole extending inwardly from the respective groove to the spool contact surface of said sleeve member, the radial holes communicating with each load port groove each being of relatively small diameter with the longitudinally outwardly spaced series of holes for each load port having an enlarged coaxial diameter portion communicating between the respective load port groove and the small diameter portion extending inwardly to said spool contact surface whereby increased flow is adapted to be provided by said enlarged diameter portion, and a pair of longitudinally spaced peripheral seals carried by said spool for each load port with said seals adapted to be positioned longitudinally outwardly of either respective series of small diameter radial holes of the respective load port in response to said spool being positioned to connect the pressure port with the respective load port for controlling the flow rate through said load port accordingly.
Claim 2
Dependent Claim
329 words
In a spool valve including a valve casing having means defining a longitudinally extending internal fluid cavity, a plurality of longitudinally spaced fluid ports carried by said casing and opening up into said cavity with two of said ports being load ports longitudinally spaced on respective opposite sides of a pressure port, a cylindrical spool coaxially positioned within said casing cavity for reciprocating movement along said casing axis, the improvement comprising: a sleeve assembly fixedly positioned within said casing and concentrically positioned between said spool and said casing internal wall with said sleeve assembly having at least a spool contact surface formed of a nylon-molybdenum disulfide composition, a unitary sleeve member formed entirely of nylon-molybdenum disulfide composition having a plurality of longitudinally spaced circumferential grooves in the outer periphery of said sleeve membEr each communicating with a respective one of said longitudinally spaced fluid pressure and load ports, said sleeve member having a series of circumferentially spaced, radial holes for said pressure port and a plurality of longitudinally spaced series of circumferentially spaced radial holes for each load port with each radial hole extending inwardly from the respective groove to the spool contact surface of said sleeve member, the radial holes communicating with each load port groove each being of relatively small diameter with the longitudinally outwardly spaced series of holes for each load port having an enlarged coaxial diameter portion communicating between the respective load port groove and the small diameter portion extending inwardly to said spool contact surface whereby increased flow is adapted to be provided by said enlarged diameter portion, and a pair of longitudinally spaced peripheral seals carried by said spool for each load port with said seals adapted to be positioned longitudinally outwardly of either respective series of small diameter radial holes of the respective load port in response to said spool being positioned to connect the pressure port with the respective load port for controlling the flow rate through said load port accordingly.
Claim 3
Dependent Claim
141 words
In a spool valve including a valve casing having means defining a longitudinally extending internal fluid cavity, a plurality of longitudinally spaced fluid ports carried by said casing and opening up into said cavity, a cylindrical spool coaxially positioned within said casing cavity for reciprocating movement along said casing axis, the improvement comprising: a unitary sleeve assembly formed entirely of nylon-molybdenum disulfide fixedly positioned within said casing and concentrically positioned between said spool and said casing internal wall with said sleeve assembly having at least a spool contact surface formed of a nylon-molybdenum disulfide composition, said sleeve member having annular slots formed within the ends of said sleeve member, and annular metal rings received by said slots and at least flush with the ends of said sleeve member to facilitate the fixed positioning of said sleeve member within said casing cavity.
Claim 4
Dependent Claim
141 words
In a spool valve including a valve casing having means defining a longitudinally extending internal fluid cavity, a plurality of longitudinally spaced fluid ports carried by said casing and opening up into said cavity, a cylindrical spool coaxially positioned within said casing cavity for reciprocating movement along said casing axis, the improvement comprising: a unitary sleeve assembly formed entirely of nylon-molybdenum disulfide fixedly positioned within said casing and concentrically positioned between said spool and said casing internal wall with said sleeve assembly having at least a spool contact surface formed of a nylon-molybdenum disulfide composition, said sleeve member having annular slots formed within the ends of said sleeve member, and annular metal rings received by said slots and at least flush with the ends of said sleeve member to facilitate the fixed positioning of said sleeve member within said casing cavity.
Claim 5
Dependent Claim
40 words
The spool valve as claimed in claim 2 wherein; said annular metal rings are formed of stainless steel and L-shaped in cross section and having radial flanges which extend radially outwardly from said annular slots toward said casing side walls.
Claim 6
Dependent Claim
293 words
In a spool valve including a valve casing having means defining a longitudinally extending internal fluid cavity, a plurality of longitudinally spaced fluid ports carried by said casing and opening up into said cavity, a cylindrical spool coaxially positioned within said casing cavity for reciprocating movement along said casing axis to opposite limit positions, the improvement comprising: a sleeve assembly fixedly positioned within said casing and concentrically positioned between said spool and said casing internal wall with said sleeve assembly having at least a spool contact surface formed of nylon-molybdenum disulfide composition, means on said casing defining a central fluid pressure inlet port and a pair of pressurized fluid load ports each longitudinally spaced on a respective opposite side of said inlet port, means defining a fluid pressure exhaust port in said casing longitudinally spaced adjacent one of said load ports, means carried by said spool for alternately connecting and disconnecting the central fluid pressure inlet port with a respective one of said pressurized fluid load ports and alternately connecting said exhaust port with said one load port in response to said spool being reciprocated to a respective one of said opposite limit positions, said cylindrical spool having a central bore in continuous connection with said exhaust port and alternately connected with the other load port in response to said spool being reciprocated to a limit position in which said other load port is disconnected from said inlet port, aNd means in said bore automatically operated in response to the movement of said spool from each limit position for applying fluid pressure from the load port disconnected from said inlet port to assist the movement of said spool in a respective direction for further disconnecting said disconnected load port from said inlet port.
Claim 7
Dependent Claim
293 words
In a spool valve including a valve casing having means defining a longitudinally extending internal fluid cavity, a plurality of longitudinally spaced fluid ports carried by said casing and opening up into said cavity, a cylindrical spool coaxially positioned within said casing cavity for reciprocating movement along said casing axis to opposite limit positions, the improvement comprising: a sleeve assembly fixedly positioned within said casing and concentrically positioned between said spool and said casing internal wall with said sleeve assembly having at least a spool contact surface formed of nylon-molybdenum disulfide composition, means on said casing defining a central fluid pressure inlet port and a pair of pressurized fluid load ports each longitudinally spaced on a respective opposite side of said inlet port, means defining a fluid pressure exhaust port in said casing longitudinally spaced adjacent one of said load ports, means carried by said spool for alternately connecting and disconnecting the central fluid pressure inlet port with a respective one of said pressurized fluid load ports and alternately connecting said exhaust port with said one load port in response to said spool being reciprocated to a respective one of said opposite limit positions, said cylindrical spool having a central bore in continuous connection with said exhaust port and alternately connected with the other load port in response to said spool being reciprocated to a limit position in which said other load port is disconnected from said inlet port, aNd means in said bore automatically operated in response to the movement of said spool from each limit position for applying fluid pressure from the load port disconnected from said inlet port to assist the movement of said spool in a respective direction for further disconnecting said disconnected load port from said inlet port.
Claim 8
Dependent Claim
150 words
The spool valve as claimed in claim 4 wherein said bore in said spool has at least one radially projecting, small-diameter hole for each load port extending from said spool bore to the outer surface thereof adapted to communicate fluid pressure from the respective load port to said bore after disconnection of said load port from said inlet pressure port, and said automatically operated means comprises a tube of slightly smaller diameter than said spool valve bore, having a flared end and fixedly positioned with said bore, and a ball valve of lesser diameter than said bore but of a larger diameter than the internal diameter of said tube positioned within said spool bore, between said tube flared end and one said spool radial hole for engagement alternately with said flared end and one radial hole in response to fluid pressure applied respectively through said one radial hole and tube.
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) | 1974-05-24 | 1974-11-23 | 1975-05-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-05-24 | 1978-11-23 | 1979-05-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-05-24 | 1982-11-23 | 1983-05-25 | $7700.00 | Window Closed / Lapsed |