US3656076A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Time delay electromagnetic device
Assignee: RTX Corp
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Filing: 1970-02-02
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Granted: 1972-04-11
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Expires: 1990-02-02
Abstract
Abstract A time delay electromagnetic device includes a core for an electromagnetic coil having a tubular sleeve comprising a magnetizable and a non-magnetizable portion which is sealed at one end by a magnetizable pole piece and substantially filled with a damping liquid. A magnetizable plunger is positioned within the sleeve and includes a ball retaining cage and ball check valve positioned in a passage extending through the plunger. The cage is closed at one end and includes an aperture therein. When the plunger is attracted to the pole piece, the ball check valve blocks the flow of the liquid through the passage, causing the liquid to pass through a small space between the plunger and the sleeve to delay the movement of the plunger toward the pole piece.
Inventors
- 👤 Robert E Prouty
- 👤 John E Gilman
- 👤 James J Smith
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 02:24
CPC Classifications
H; H01; H01H; H01H50/00; H01H50/86; H01H50/88; H01F; H01F7/00; H01F7/06; H01F7/08; H01F7/088
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
246 words
A time delayed electromagnetic device of the type which is adapted to be actuated in response to a magnetic flux field, said device including a closed elongated stationary tubular sleeve substantially filled with fluid and adapted to be positioned in said field, magnetizable pole means at one end of said sleeve, a magnetizable tubular plunger positioned in said sleeve for axial movement therein in response to the condition of said flux field, said plunger having a fluid flow passage extending axially therethrough and check means associated therewith for controlling the flow through said passage, the improvement in said check means comprising in combination therewith: tubular cage means inserted into and fixed in said passage, the end of said cage means opposite said pole means being closed and having an aperture defined therein which communicates said passage with said sleeve, at least one finger means formed integrally with said cage means and extending in angular relationship to the axis of said tubular cage means, and ball means loosely positioned in said cage means and movable between said aperture and finger means, whereby when said plunger moves in a direction toward said pole means, said ball means moves into overlying relationship with said aperture to restrict the flow of fluid through said cage means and passage and when said plunger moves in a direction away from said pole means said ball means moves away from said aperture and is retained in said cage means by said finger means.
Claim 2
Dependent Claim
246 words
A time delayed electromagnetic device of the type which is adapted to be actuated in response to a magnetic flux field, said device including a closed elongated stationary tubular sleeve substantially filled with fluid and adapted to be positioned in said field, magnetizable pole means at one end of said sleeve, a magnetizable tubular plunger positioned in said sleeve for axial movement therein in response to the condition of said flux field, said plunger having a fluid flow passage extending axially therethrough and check means associated therewith for controlling the flow through said passage, the improvement in said check means comprising in combination therewith: tubular cage means inserted into and fixed in said passage, the end of said cage means opposite said pole means being closed and having an aperture defined therein which communicates said passage with said sleeve, at least one finger means formed integrally with said cage means and extending in angular relationship to the axis of said tubular cage means, and ball means loosely positioned in said cage means and movable between said aperture and finger means, whereby when said plunger moves in a direction toward said pole means, said ball means moves into overlying relationship with said aperture to restrict the flow of fluid through said cage means and passage and when said plunger moves in a direction away from said pole means said ball means moves away from said aperture and is retained in said cage means by said finger means.
Claim 3
Dependent Claim
15 words
The device of claim 1 wherein said cage means is formed of a non-magnetizable material.
Claim 4
Dependent Claim
22 words
The device of claim 1 wherein said cage means is insertably positioned at the end of said passage opposite said pole means.
Claim 5
Dependent Claim
50 words
The device of claim 3 wherein said closed end of said cage means comprises flange means formed integrally with said cage means and having a diameter larger than the diameter of said passage, said flange means being positioned between the ends of said plunger and sleeve opposite said pole means.
Claim 6
Dependent Claim
36 words
In the device of claim 1 including spring means in said sleeve for moving said plunger in a direction away from said pole means, said spring means bearing against said finger means opposite said ball means.
Claim 7
Dependent Claim
16 words
The device of claim 1 including non-magnetizable shading means between said pole means and said plunger.
Claim 8
Dependent Claim
41 words
The device of claim 4 wherein the diameter of said flange means is greater than the diameter of said plunger and the diameter of said plunger over a major portion of its length is less than the diameter of said sleeve.
Claim 9
Dependent Claim
25 words
The device of claim 1 wherein said elongated sleeve is magnetizable over a portion of its length and non-magnetizable over another portion of its length.
Claim 10
Dependent Claim
231 words
A time delayed electromagnetic device comprising: a plurality of conductive windings forming a coil, a core positioned within said coil and forming substantially the entire magnetic circuit of said coil, said core comprising, an elongated sealed sleeve substantially filled with fluid, a portion of said sleeve being non-magnetizable, a magnetizable pole piece positioned adjacent one end of said sleeve and said coil, said non-magnetizable portion of said sleeve being adjacent said pole piece. a magnetizable tubular plunger moveAbly positioned in said sleeve and having a passage extending therethrough, urging means normally urging said plunger toward the other end of said sleeve with a force insufficient to overcome the magnetic force exerted on said sleeve by said pole piece, and check means in said plunger comprising tubular cage means inserted axially into and fixed in said passage, one end of said cage means being closed and having an aperture therethrough which communicates said passage with said sleeve, ball valve means loosely positioned in said cage means and movable relative to said aperture so as to block the flow of fluid through said aperture and passage when said magnetic force is exerted on said plunger by said pole piece, and at least one resilient finger bent from said cage means and retaining said ball means in said cage means when said urging means urges said plunger toward said other end of said sleeve.
Claim 11
Dependent Claim
231 words
A time delayed electromagnetic device comprising: a plurality of conductive windings forming a coil, a core positioned within said coil and forming substantially the entire magnetic circuit of said coil, said core comprising, an elongated sealed sleeve substantially filled with fluid, a portion of said sleeve being non-magnetizable, a magnetizable pole piece positioned adjacent one end of said sleeve and said coil, said non-magnetizable portion of said sleeve being adjacent said pole piece. a magnetizable tubular plunger moveAbly positioned in said sleeve and having a passage extending therethrough, urging means normally urging said plunger toward the other end of said sleeve with a force insufficient to overcome the magnetic force exerted on said sleeve by said pole piece, and check means in said plunger comprising tubular cage means inserted axially into and fixed in said passage, one end of said cage means being closed and having an aperture therethrough which communicates said passage with said sleeve, ball valve means loosely positioned in said cage means and movable relative to said aperture so as to block the flow of fluid through said aperture and passage when said magnetic force is exerted on said plunger by said pole piece, and at least one resilient finger bent from said cage means and retaining said ball means in said cage means when said urging means urges said plunger toward said other end of said sleeve.
Claim 12
Dependent Claim
16 words
The device of claim 9 wherein said elongated sleeve is positioned substantially entirely within said coil.
Claim 13
Dependent Claim
40 words
The device of claim 9 wherein said one end of said cage means is closed by flange means formed integrally with said tubular cage means, said flange means being positioned between said plunger and said other end of said sleeve.
Claim 14
Dependent Claim
38 words
The device of claim 9 wherein said plunger is spaced slightly from said sleeve to define a space therebetween, said fluid flowing through said space when said ball valve means blocks the flow of fluid through said aperture.
Claim 15
Dependent Claim
129 words
A time delayed electromagnetic device of the type which is adapted to be actuated in response to a magnetic flux field, said device including a closed elongated stationary tubular sleeve substantially filled with fluid and adapted to be positioned in said field, magnetizable pole means at one end of said sleeve, a magnetizable tubular plunger positioned in said sleeve for axial movement therein in response to the condition of said flux field toward and away from said pole means, and check means restraining the movement of said plunger toward said pole means, the improvement comprising in combination therewith: first shading means positioned on said pole means external of said sleeve, and second shading means adjacent said pole means internal of said sleeve between said pole means and said plunger.
Claim 16
Dependent Claim
129 words
A time delayed electromagnetic device of the type which is adapted to be actuated in response to a magnetic flux field, said device including a closed elongated stationary tubular sleeve substantially filled with fluid and adapted to be positioned in said field, magnetizable pole means at one end of said sleeve, a magnetizable tubular plunger positioned in said sleeve for axial movement therein in response to the condition of said flux field toward and away from said pole means, and check means restraining the movement of said plunger toward said pole means, the improvement comprising in combination therewith: first shading means positioned on said pole means external of said sleeve, and second shading means adjacent said pole means internal of said sleeve between said pole means and said plunger.
Claim 17
Dependent Claim
23 words
The device of claim 13 wherein said shading means are non-magnetizable and said second shading means comprises a ring on said pole means.
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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) | 1975-04-11 | 1975-10-11 | 1976-04-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-04-11 | 1979-10-11 | 1980-04-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-04-11 | 1983-10-11 | 1984-04-11 | $7700.00 | Window Closed / Lapsed |