US3794868A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electromagnetic device
Assignee: Individual
•
Filing: 1971-08-31
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Granted: 1974-02-26
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Expires: 1991-08-31
Abstract
Abstract An electro-magnetic torque motor has a permanent magnet pivotally mounted in a hollow frame of magnetisable material. Surrounding the magnet within the frame is a winding whose magnetic axis is angularly displaced from the magnetic axis of the magnet when the winding is not energised. Energisation of the winding tends to rotate the magnet within the winding in a direction to align the magnetic axes.
Inventors
- 👤 R Haigh
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 11:17
CPC Classifications
H; H01; H01F; H01F7/00; H01F7/06; H01F7/08; H01F7/14; F; F02; F02D; F02D9/00; F02D2700/00; F02D2700/02; F02D2700/0217; F02D2700/0261; F02D2700/0266
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
181 words
An electro magnetic torque motor comprising a frame formed from a material of high magnetic permeability and defining an internal cavity, said frame including a pair of side members extending in planes which are substantially mutually parallel, a permanent magnet mounted within said cavity for pivotal movement about an axis substantially parallel to the planes of said side members, the faces of the magnet adjacent the side members being of opposite polarity, so that in the absence of an external force on said magnet the latter moves towards an equilibrium position, relative to said frame, in which there is minimum reluctance in the flux path from the magnet, and a winding disposed in said cavity, the winding having a magnetic access which is substantially perpendicular to the pivotal access of the magnet and substantially parallel to the planes of the side members, the arrangement being such that when the winding energised the magnet will tend to turn about its pivotal axis away from equilibrium position to a position in which its magnetic axis will be aligned with that of the winding.
Claim 2
Dependent Claim
181 words
An electro magnetic torque motor comprising a frame formed from a material of high magnetic permeability and defining an internal cavity, said frame including a pair of side members extending in planes which are substantially mutually parallel, a permanent magnet mounted within said cavity for pivotal movement about an axis substantially parallel to the planes of said side members, the faces of the magnet adjacent the side members being of opposite polarity, so that in the absence of an external force on said magnet the latter moves towards an equilibrium position, relative to said frame, in which there is minimum reluctance in the flux path from the magnet, and a winding disposed in said cavity, the winding having a magnetic access which is substantially perpendicular to the pivotal access of the magnet and substantially parallel to the planes of the side members, the arrangement being such that when the winding energised the magnet will tend to turn about its pivotal axis away from equilibrium position to a position in which its magnetic axis will be aligned with that of the winding.
Claim 3
Dependent Claim
23 words
A torque motor as claimed in claim 1 in which the magnet has a substantially rectangular cross section perpendicular to its pivotal axis.
Claim 4
Dependent Claim
26 words
A torque motor as claimed in claim 2 in which the winding has a substantially triangular cross section perpendicular to the pivotal axis of the magnet.
Claim 5
Dependent Claim
31 words
A torque motor as claimed in claim 1 in which the surface of the magnet adjacent the windings is a surface of revolution centred on the pivotal axis of the magnet.
Claim 6
Dependent Claim
15 words
A torque motor as claimed in claim 4 in which the magnet is substantially cylindrical.
Claim 7
Dependent Claim
16 words
A torque motor as claimed in claim 4 in which the side members are part cylindrical.
Claim 8
Dependent Claim
25 words
A torque motor as claimed in claim 4 in which the windings define surfaces which lie closely adjacent the surfaces of revolution of the magnet.
Claim 9
Dependent Claim
81 words
A fluid flow control valve comprising an inlet, an outlet, a torque motor as claimed in claim 1, a spindle rotatable by the magnet, a projection on the spindle and a valve closure member between the inlet and the outlet and engageable by the projection to shut the valve when the spindle is in one angular position, the closure member being movable in response to a pressure at the inlet to open the valve in other angular positions of the spindle.
Claim 10
Dependent Claim
29 words
A valve as claimed in claim 1 in which the closure member is a half ball and the projection is engageable with the part-spherical surface of the half ball.
Claim 11
Dependent Claim
22 words
A valve as claimed in claim 9 in which the axis of the said spindle is spaced from the said part-spherical surface.
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) | 1977-02-25 | 1977-08-27 | 1978-02-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-02-25 | 1981-08-27 | 1982-02-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-02-25 | 1985-08-27 | 1986-02-26 | $7700.00 | Window Closed / Lapsed |