US3828288A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnetic actuator device
Assignee: Allis Chalmers Corp
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Filing: 1973-05-29
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Granted: 1974-08-06
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Expires: 1993-05-29
Abstract
Abstract There is provided in accordance with an embodiment of the invention a magnetic actuator device comprising an annular-shaped permanent magnet having magnetic pole pieces in contact with the opposite axial ends of the permanent magnet. A bobbin member of a nonmagnetic electrically insulating material such as nylon is coaxially and concentrically positioned within the central opening of the annular permanent magnet. A trip coil connected to an electrical signal source is positioned on the hollow cylindrical hub of the bobbin. A cylindrical plunger or armature of magnetic material is positioned for axial linear sliding movement in the hollow hub of the bobbin. The forward end of the plunger carries a colored stud member which projects forwardly of the front pole piece and serves by its position as an indicator of whether the magnetic actuator device is in tripped or untripped condition. The rearwardly facing end of the magnetic plunger carries a nonmagnetic spindle which projects rearwardly through the rear pole piece and bears against a spiral spring mounted on the rear or outer surface of the rear pole piece. Normally, the magnetic actuator device is in a magnetically latched condition in which the rearwardly facing end of the plunger bears against the inner face of the rear pole piece, with the armature being held in this magnetically latched position against the force of the spring by the magnetic flux from the permanent magnet passing through the magnetic plunger. Upon the receipt of a momentary electrical signal pulse on the coil, a magnetomotive force with resulting magnetic flux is set up by the coil which opposes the magnetic flux of the permanent magnet to a sufficient extent to permit the spring to rapidly move the plunger to its forward or tripped position, thereby causing the signal indicator carried by the plunger to be projected forwardly to a position in which it indicates that the magnetic actuator device has been tripped. The linear movement of the plunger to tripped position upon the receipt of a trip signal on the coil may also be used to actuate a suitable switch, such as a microswitch, positioned contiguous the magnetic actuator device. The magnetic actuator device may be reset after tripping by manually pushing the plunger rearwardly against the spring force until it magnetically latches against the inner surface of the rear pole piece.
Inventors
- 👤 D Boyd
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 12:51
CPC Classifications
H; H01; H01F; H01F7/00; H01F7/06; H01F7/08; H01F7/16; H01F7/1607; H01F7/1615; G; G08; G08B; G08B5/00; G08B5/22; H01F7/165; H01F7/121; H01F7/122; H01H; H01H71/00; H01H71/10; H01H71/12; H01H71/24; H01H71/32; H01H71/321; H01H71/322
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
297 words
A magnetic actuator device comprising a permanent magnet, said magnet having a central opening therein, a bobbin of nonmagnetic material positioned within said central opening in concentric coaxial relation to said permanent magnet, an electrical winding positioned on said bobbin, said winding being adapted to be connected to an electric signal source, a first magnetic pole piece in contact with one axial end of said permanent magnet, a second magnetic pole piece in contact with the opposite axial end of said permanent magnet, said bobbin having a hollow hub lying substantially along the central longitudinal axis of said actuator device, a magnetic armature positioned in said hollow hub of said bobbin and being axially movable along said hub, means carried by said armature at one end of said armature contiguous said first magnetic pole piece, said means being movable by movement of said armature to an extended position forwardly of said first magnetic pole piece, a spindle member carried by the opposite end of said armature and movable with said armature, said spindle member extending through a passage in said second magnetic pole piece, a spring mounted on the outer surface of said second magnetic pole piece, said spindle member engaging said spring, said armature being movable against the force of said spring to a position in which it is magnetically latched by magnetic flux from said permanent magnet against the inner surface of said second magnetic pole piece, a signal on said electrical winding being effective to counteract the magnetic effect of said permanent magnet of said armature sufficiently to permit said spring to move saId armature axially away from said second pole piece, whereby to cause said means carried by said armature to be projected to an extended position forwardly of said first pole piece.
Claim 2
Dependent Claim
297 words
A magnetic actuator device comprising a permanent magnet, said magnet having a central opening therein, a bobbin of nonmagnetic material positioned within said central opening in concentric coaxial relation to said permanent magnet, an electrical winding positioned on said bobbin, said winding being adapted to be connected to an electric signal source, a first magnetic pole piece in contact with one axial end of said permanent magnet, a second magnetic pole piece in contact with the opposite axial end of said permanent magnet, said bobbin having a hollow hub lying substantially along the central longitudinal axis of said actuator device, a magnetic armature positioned in said hollow hub of said bobbin and being axially movable along said hub, means carried by said armature at one end of said armature contiguous said first magnetic pole piece, said means being movable by movement of said armature to an extended position forwardly of said first magnetic pole piece, a spindle member carried by the opposite end of said armature and movable with said armature, said spindle member extending through a passage in said second magnetic pole piece, a spring mounted on the outer surface of said second magnetic pole piece, said spindle member engaging said spring, said armature being movable against the force of said spring to a position in which it is magnetically latched by magnetic flux from said permanent magnet against the inner surface of said second magnetic pole piece, a signal on said electrical winding being effective to counteract the magnetic effect of said permanent magnet of said armature sufficiently to permit said spring to move saId armature axially away from said second pole piece, whereby to cause said means carried by said armature to be projected to an extended position forwardly of said first pole piece.
Claim 3
Dependent Claim
40 words
A magnetic actuator device as defined in claim 1 in which said means carried by said armature at said one end of said armature is an indicating device to indicate whether said actuator device has been moved to tripped position.
Claim 4
Dependent Claim
30 words
A magnetic actuator device as defined in claim 1 in which said means carried by said armature comprises a sleeve-like stud member mounted on an integral extension of said armature.
Claim 5
Dependent Claim
53 words
A magnetic actuator device as defined in claim 1 comprising a sheet of spring-like metal secured to said outer surface of said second pole piece, and a spiral spring etched from said sheet of metal but remaining connected to said sheet of metal, said spindle engaging and being engaged by said spiral spring.
Claim 6
Dependent Claim
105 words
A magnetic actuator device as defined in claim 4 in which said first pole piece has a circular outer periphery having a diameter substantially the same as the outer diameter of said annular permanent magnet, said second pole piece having a semicircular outer periphery having substantially the same radius as the outer radius of said annular permanent magnet, the remaining portion of the periphery of said second pole piece being of generally rectangular-shape and formed of straight edges, the outer peripheral contour of said sheet of spring-like metal being substantially the same as the peripheral contour of the outer face of said second pole piece.
Claim 7
Dependent Claim
28 words
A magnetic actuator device as defined in claim 1 in which said permanent magnet is of annular shape, and said central opening is defined by said annular shape.
Claim 8
Dependent Claim
58 words
A magnetic actuator device as defined in claim 1 in which the axial end of said armature which magnetically latches against the inner surface of said second magnetic pole piece lies substantially entirely radially inwardly of said permanent magnet and has a substantially smaller area than the area of said inner surface of said second magnetic pole piece.
Claim 9
Dependent Claim
18 words
A magnetic actuator device as defined in claim 1 in which said spindle is made of nonmagnetic material.
Claim 10
Dependent Claim
62 words
A magnetic actuator device as defined in claim 1 in which said means carried by said armature remains projected in said extended position until said armature is reset by a force external of said device against the force of said spring to a position in which said armature is again magnetically latched against the inner surface of said second magnetic pole piece.
Claim 11
Dependent Claim
134 words
A magnetic actuator device as defined in claim 1 in which said spindle includes an enlarged head portion engaging said spring, said head portion serving as a stop which engages the outer surface of said second pole piece to limit the tripping movement of said armature, the distance of the axial tripping movement of said armature as determined by the position of said head portion being such that upon completion of said tripping movement said armature has moved a sufficient axial distance away from the inner surface of said magnetic pole piece that said armature must be reset by a force external of said magnetic actuator device against the force of said spring to a position in which said armature is again magnetically latched against the inner surface of said second magnetic pole piece.
Claim 12
Dependent Claim
350 words
A magnetic actuator device comprising a permanent magnet, said magnet having a central opening therein, a bobbin of nonmagnetic material positioned within said central opening in coaxial relation to said permanent magnet, an electrical winding positioned on said bobbin, said winding being adapted to be connected to an electric signal source, a first magnetic pole piece in contact with one axial end of said permanent magnet, a second magnetic pole piece in contact with the opposite axial end of said permanent magnet, said bobbin having a hollow hub lying substantially along the central longitudinal axis of said actuator device, a magnetic armAture positioned in said hollow hub of said bobbin and being axially movable along said hub, an indicator device carried by said armature at one end of said armature contiguous said first magnetic pole piece, said indicator device being movable by movement of said armature to an extended position forwardly of said first magnetic pole piece, a spindle member carried by the opposite end of said armature and movable with said armature, said spindle member extending through a passage in said second magnetic pole piece, a spring mounted on the outer surface of said second magnetic pole piece, said spindle member engaging said spring, said armature being movable against the force of said spring to a position in which it is magnetically latched by magnetic flux from said permanent magnet against the inner surface of said second magnetic pole piece, a signal on said electrical winding being effective to counteract the magnetic effect of said permanent magnet on said armature sufficiently to permit said spring to move said armature axially away from said second pole piece, whereby to cause said indicator device carried by said armature to be projected to said extended position forwardly of said first pole piece, said indicator device remaining projected in said extended position until said armature is reset by a force external of said magnetic actuator device against the force of said spring to a position in which said armature is again magnetically latched against the inner surface of said second magnetic pole piece.
Claim 13
Dependent Claim
350 words
A magnetic actuator device comprising a permanent magnet, said magnet having a central opening therein, a bobbin of nonmagnetic material positioned within said central opening in coaxial relation to said permanent magnet, an electrical winding positioned on said bobbin, said winding being adapted to be connected to an electric signal source, a first magnetic pole piece in contact with one axial end of said permanent magnet, a second magnetic pole piece in contact with the opposite axial end of said permanent magnet, said bobbin having a hollow hub lying substantially along the central longitudinal axis of said actuator device, a magnetic armAture positioned in said hollow hub of said bobbin and being axially movable along said hub, an indicator device carried by said armature at one end of said armature contiguous said first magnetic pole piece, said indicator device being movable by movement of said armature to an extended position forwardly of said first magnetic pole piece, a spindle member carried by the opposite end of said armature and movable with said armature, said spindle member extending through a passage in said second magnetic pole piece, a spring mounted on the outer surface of said second magnetic pole piece, said spindle member engaging said spring, said armature being movable against the force of said spring to a position in which it is magnetically latched by magnetic flux from said permanent magnet against the inner surface of said second magnetic pole piece, a signal on said electrical winding being effective to counteract the magnetic effect of said permanent magnet on said armature sufficiently to permit said spring to move said armature axially away from said second pole piece, whereby to cause said indicator device carried by said armature to be projected to said extended position forwardly of said first pole piece, said indicator device remaining projected in said extended position until said armature is reset by a force external of said magnetic actuator device against the force of said spring to a position in which said armature is again magnetically latched against the inner surface of said second magnetic pole piece.
Claim 14
Dependent Claim
28 words
A magnetic actuator device as defined in claim 11 in which said permanent magnet is of annular shape, and said central opening is defined by said annular shape.
Claim 15
Dependent Claim
18 words
A magnetic actuator device as defined in claim 11 in which said spindle is made of nonmagnetic material.
Claim 16
Dependent Claim
134 words
A magnetic actuator device as defined in claim 11 in which said spindle includes an enlarged head portion engaging said spring, said head portion serving as a stop which engages the outer surface of said second pole piece to limit the tripping movement of said armature, the distance of the axial tripping movement of said armature as determined by the position of said head portion being such that upon completion of said tripping movement said armature has moved a sufficient axial distance away from the inner surface of said magnetic pole piece that said armature must be reset by a force external of said magnetic actuator device against the force of said spring to a position in which said armature is again magnetically latched against the inner surface of said second magnetic pole piece.
Claim 17
Dependent Claim
53 words
A magnetic actuator device as defined in claim 11 comprising a sheet of spring-like metal secured to said outer surface of said second pole piece, and a spiral spring etched from said sheet of metal but remaining connected to said sheet of metal, said spindle engaging and being engaged by said spiral spring.
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) | 1977-08-05 | 1978-02-04 | 1978-08-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-08-05 | 1982-02-04 | 1982-08-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-08-05 | 1986-02-04 | 1986-08-06 | $7700.00 | Window Closed / Lapsed |