US3851285A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Control magnet for hydraulic control system valves
Assignee: Robert Bosch GmbH
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Filing: 1973-10-10
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Granted: 1974-11-26
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Expires: 1993-10-10
Abstract
Abstract A control magnet for a valve of a hydraulic control system has an armature axially movable on a shaft mounted in bearings for axial displacement. A compression spring between one end of the shaft and an end of the casing surrounding the device has a stiffness low enough so as to push the armature partly out of the coil all the way to its rest position from any initial position. The armature has longitudinal bores and grooves so that the surrounding medium will not interfere with quick operating time of the magnet. An annular core extends part way inside the winding and surrounds the compression spring.
Inventors
- 👤 G Rothfuss
- 👤 H Gand
- 👤 W Bredenbrock
- 👤 W Bohringer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 09:58
CPC Classifications
H; H01; H01F; H01F7/00; H01F7/06; H01F7/08; H01F7/16; H01F7/1607; F; F16; F16H; F16H61/00; F16K; F16K31/00; F16K31/02; F16K31/06; F16H2710/00; F16H2710/16; F16H2710/22; F16H61/02; F16H61/0202; F16H61/0251; H01F7/081; H01F2007/085
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
133 words
A control magnet suitable for magnetic valves comprising: a casing (11); an annular magnet winding (26) inside said casing; an armature (19) movable within said casing affixed on a rod (18) provided with bearings mounted in said casing for guiding and permitting axial movement of said armature in and out of said winding coaxially therewith, said armature being affixed to said rod at a position on said rod which is between said bearings and being provided with axially extending cavities, (24, 25), said rod having one extremity protruding into said winding and the other extremity wholly outside of said winding; and a compression spring held between said casing and the extremity of said rod which protrudes into said winding and arranged to urge said rod out of the space enclosed by said winding.
Claim 2
Dependent Claim
133 words
A control magnet suitable for magnetic valves comprising: a casing (11); an annular magnet winding (26) inside said casing; an armature (19) movable within said casing affixed on a rod (18) provided with bearings mounted in said casing for guiding and permitting axial movement of said armature in and out of said winding coaxially therewith, said armature being affixed to said rod at a position on said rod which is between said bearings and being provided with axially extending cavities, (24, 25), said rod having one extremity protruding into said winding and the other extremity wholly outside of said winding; and a compression spring held between said casing and the extremity of said rod which protrudes into said winding and arranged to urge said rod out of the space enclosed by said winding.
Claim 3
Dependent Claim
79 words
A control magnet as defined in claim 1 in which said compression spring (16) has a stiffness sufficiently small and an axial displacement in compression sufficiently large that said armature (19) is pressed all the way to its end rest position by said spring from any position it may assume when released, whereas the force of said compression spring may nevertheless be overcome by the attraction of the armature from its end rest position when said winding is energized.
Claim 4
Dependent Claim
28 words
A control magnet as defined in claim 1 in which at least part of said cavities are axially oriented grooves (24) on the periphery of said armature (19).
Claim 5
Dependent Claim
27 words
A control magnet as defined in claim 1 in which at least part of said cavities are bores (25) parallel to the axis of said armature (19).
Claim 6
Dependent Claim
22 words
A control magnet as defined in claim 1 in which said bearings are ball bearings disposed for axial movement of said rod.
Claim 7
Dependent Claim
24 words
A control magnet as defined in claim 1 in which said bearings are sliding surface bearings provided with polytetrafluoroethylene layers on the bearing surfaces.
Claim 8
Dependent Claim
21 words
A control magnet as defined in claim 1 in which said casing (11) provides a ferromagnetic path for the magnetic flux.
Claim 9
Dependent Claim
46 words
A control magnet as defined in claim 1 in which near the end of said winding away from said compression spring (16) a re-entrant cylindrical projection (33) of said casing provides a recess into which said end of said armature fits with a peripheral air gap.
Claim 10
Dependent Claim
39 words
A control magnet as defined in claim 8 in which in the quiescent position of said armature (19) said recess of said casing (11) closely surrounds said body of said armature for at least half of its axial length.
Claim 11
Dependent Claim
43 words
A control magnet as defined in claim 1 in which a tubular core (14) affixed to said casing extends inside said winding and slightly overlaps, without touching, said armature in the rest position of said armature, and also surrounds said compression spring (16).
Claim 12
Dependent Claim
29 words
A control magnet as defined in claim 10 in which said body of said armature (19) is beveled towards its end which is nearer to said compression spring (16).
Claim 13
Dependent Claim
26 words
A control magnet as defined in claim 11 in which the free end of the inner surface of said core (14) has an outward flare (31).
Claim 14
Dependent Claim
62 words
A control magnet as defined in claim 4 in which said armature includes an inner portion made of molded synthetic material forming an intermediate layer between the magnetic portion of said armature and the rod (18) on which said armature is mounted, and in which said bores (25) are located in the portion of said armature which is made of synthetic material.
Claim 15
Dependent Claim
36 words
A control magnet as defined in claim 1 in which said rod (18) is a substantially cylindrical rod and has a diameter that is less than half as great as the diameter of said armature (19).
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) | 1977-11-25 | 1978-05-27 | 1978-11-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-11-25 | 1982-05-27 | 1982-11-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-11-25 | 1986-05-27 | 1986-11-26 | $7700.00 | Window Closed / Lapsed |