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US4518938A Expired / Lapsed US ⏱️ 0.0 years remaining

Solenoid having low-friction coating internally of the armature sleeve

Assignee: Bosch Rexroth AG
•
Filing: 1984-03-01
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Granted: 1985-05-21
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Expires: 2004-03-01
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Abstract

Abstract Electromagnet solenoid with a housing in which a winding support supporting the magnet winding is arranged, having an armature which supports at least one stem and is mounted to be capable of moving to and fro within the winding support, and with end pieces terminating the housing. For guiding the armature a sleeve made of magnetic material is provided within the winding support, and said sleeve has on its surface directed towards the armature a sliding coating defining an air gap (i.e. a space free of magnetic material,) and in addition to serving for guiding the armature the said sleeve serves for redirecting magnetic flux.

Inventors

  • 👤 Reiner Bartholomaus
  • 👤 Christoph Gibas

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-07 10:16
CPC Classifications
H; H01; H01F; H01F7/00; H01F7/06; H01F7/08; H01F7/16; H01F7/1607; H01F7/081; H01F2007/085

Claims Analysis

Total Claims: 22
Claim 1
Independent Claim 18 words
A solenoid comprising: a housing having two ends; winding means adapted for being energized by flow of electricity;
Claim 2
Dependent Claim 18 words
A solenoid comprising: a housing having two ends; winding means adapted for being energized by flow of electricity;
Claim 3
Dependent Claim 137 words
winding support means, arranged within said housing, for supporting said winding means; an armature mounted for reciprocal movement within said winding support means in response to energization of said winding means; sleeve means, provided radially inward of said winding support means, for guiding said armature during its movement including a magnetically conductive supporting element provided on its inner surface with a non-magnetic low friction coating adapted to contact said armature so as to define an air gap facing said armature and a low friction bearing for said armature; at least one stem extending from said armature; first end piece means for closing one end of said housing; second end piece means for closing the other end of said housing; and bearing means, provided in one of said first and second end piece means, for guiding said stem.
Claim 4
Dependent Claim 137 words
winding support means, arranged within said housing, for supporting said winding means; an armature mounted for reciprocal movement within said winding support means in response to energization of said winding means; sleeve means, provided radially inward of said winding support means, for guiding said armature during its movement including a magnetically conductive supporting element provided on its inner surface with a non-magnetic low friction coating adapted to contact said armature so as to define an air gap facing said armature and a low friction bearing for said armature; at least one stem extending from said armature; first end piece means for closing one end of said housing; second end piece means for closing the other end of said housing; and bearing means, provided in one of said first and second end piece means, for guiding said stem.
Claim 5
Dependent Claim 13 words
A solenoid according to claim 1, wherein said solenoid comprises a switch magnet.
Claim 6
Dependent Claim 13 words
A solenoid according to claim 1, wherein said solenoid comprises a proportional magnet.
Claim 7
Dependent Claim 14 words
A solenoid according to claim 1, wherein said sleeve means is a DU sleeve.
Claim 8
Dependent Claim 38 words
A solenoid as in claim 1 wherein said bearing means is a sleeve inserted in said second end piece means and said second end piece includes a tapered nose extending toward said first end piece about said armature.
Claim 9
Dependent Claim 21 words
A solenoid according to claim 1, wherein said sleeve means are inserted in a bore formed within the winding support means.
Claim 10
Dependent Claim 27 words
A solenoid according to claim 1, wherein said sleeve means comprises two sleeves which are axially spaced from each other so as to form a hollow space.
Claim 11
Dependent Claim 23 words
A solenoid according to claim 7, wherein at least one of said two sleeves is shaped so as to constitute a proportional magnet.
Claim 12
Dependent Claim 14 words
A solenoid according to claim 1, wherein said low-friction coating is comprised of polytetrafluorethylene.
Claim 13
Dependent Claim 43 words
A solenoid according to claim 1, wherein said sleeve means comprises a copper-plated steel backing, with the inner surface having sintered thereto a porous layer of tin bronze powder, the pores of which are filled with a mixture of polytetrafluoroethylene and lead powder.
Claim 14
Dependent Claim 13 words
A solenoid according to claim 7, wherein one of the sleeves tapers upwardly.
Claim 15
Dependent Claim 28 words
A solenoid according to claim 7, wherein one of said sleeves is inserted into a bore defined by a flange of said housing and said winding support means.
Claim 16
Dependent Claim 39 words
A solenoid according to claim 7, wherein one of the sleeves is situated between the cylindrical inner wall of said first end piece means, the inner wall of said winding support means and the outer periphery of said armature.
Claim 17
Dependent Claim 32 words
A solenoid according to claim 7, wherein a bore in the first end piece means widens to a bore of larger diameter, thereby forming an abutment surface for one of said sleeves.
Claim 18
Dependent Claim 35 words
A solenoid according to claim 7, wherein the winding support means comprises a radially extending widening which also forms an annular abutment surface against which at least one of the sleeves can come to bear.
Claim 19
Dependent Claim 22 words
A solenoid according to claim 7, including a further bearing sleeve arranged axially offset relatively to at least one of the sleeves.
Claim 20
Dependent Claim 31 words
A solenoid according to claim 15, wherein one of said sleeves is a bearing sleeve arranged in the winding support means to abut said widening provided on said winding support means.
Claim 21
Dependent Claim 22 words
A solenoid according to claim 1, including a magnetically operated valve in combination therewith to be operated by means of said solenoid.
Claim 22
Dependent Claim 17 words
A solenoid according to claim 18, wherein said value is constructed within said second end piece means.

References Cited (Backward Citations)

US4149132A Cited
US4278959A Cited
DE3136174A1 Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1988-05-20 1988-11-19 1989-05-21 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1992-05-20 1992-11-19 1993-05-21 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1996-05-20 1996-11-19 1997-05-21 $7700.00 Window Closed / Lapsed

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