US4250416A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Moving-coil type motor
Assignee: Ricoh Co Ltd
•
Filing: 1978-10-26
•
Granted: 1981-02-10
•
Expires: 1998-10-26
Abstract
Abstract A moving-coil type motor according to the present invention is composed of a hollow moving coil to which electrical energy is to be applied, a magnetic circuit member made of a material having high permeability which consists of an inner portion disposed within the hollow part of said moving coil and an outer portion disposed outside the same coil, said inner and outer portions being interconnected at their rear ends, and a magnet installed on said magnetic circuit member. The foregoing moving coil is fixed to an arm member supported to be capable of oscillating around a shaft, is curved into a circular arc centering around said shaft, and has a square-shaped cross section. The magnetic circuit member is also curved into a circular arc centering around the foregoing shaft similar to the moving coil, and the shape of the cross section of both the inner portion and the outer portion thereof is square similar to the shape of cross section of the moving coil.
Inventors
- 👤 Junichi Watanabe
- 👤 Hiroshi Koide
- 👤 Shigemoto Temmyo
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 09:55
CPC Classifications
H; H02; H02K; H02K33/00; H02K33/18
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
223 words
In a moving-coil type motor for limited angular movement of an object, said motor including: a hollow moving coil to which electrical energy is to be applied; a magnetic circuit member made of a material having high permeability, said magnetic circuit member including an inner portion disposed within the hollow part of said moving coil and an outer portion disposed outside said moving coil, said inner and outer portions having interconnected rear ends; and a magnet installed on said magnetic circuit member; the improvement comprising an arm member, one end of said moving coil being fixed to the fore end of said arm member, and a shaft rotatable for limited angular movement of the object about the axis of said shaft, the base of said arm member being mounted on said rotatable shaft, said moving coil being curved into a circular arc centering around said shaft and having a rectangular-shaped cross section, said magnetic circuit member also being curved into a circular arc centering around said shaft similar to the moving coil, the cross section of each of said inner and outer portions being of rectangular shape similar to that of said moving coil, the length of the moving coil along its circular arc direction being greater than the length of the magnet along the circular arc direction of the magnetic circuit member.
Claim 2
Dependent Claim
223 words
In a moving-coil type motor for limited angular movement of an object, said motor including: a hollow moving coil to which electrical energy is to be applied; a magnetic circuit member made of a material having high permeability, said magnetic circuit member including an inner portion disposed within the hollow part of said moving coil and an outer portion disposed outside said moving coil, said inner and outer portions having interconnected rear ends; and a magnet installed on said magnetic circuit member; the improvement comprising an arm member, one end of said moving coil being fixed to the fore end of said arm member, and a shaft rotatable for limited angular movement of the object about the axis of said shaft, the base of said arm member being mounted on said rotatable shaft, said moving coil being curved into a circular arc centering around said shaft and having a rectangular-shaped cross section, said magnetic circuit member also being curved into a circular arc centering around said shaft similar to the moving coil, the cross section of each of said inner and outer portions being of rectangular shape similar to that of said moving coil, the length of the moving coil along its circular arc direction being greater than the length of the magnet along the circular arc direction of the magnetic circuit member.
Claim 3
Dependent Claim
31 words
A moving-coil type motor according to claim 1, in which any one of the side walls which comprise said square cross section outer portion of the magnetic circuit member is detachable.
Claim 4
Dependent Claim
29 words
A moving-coil type motor according to claim 2, in which said one side wall is planar and has its opposite length edges curved about the axis of said shaft.
Claim 5
Dependent Claim
24 words
A moving-coil type motor according to claim 1, in which said arm member and coil form the two limbs of a substantially L-shaped configuration.
Claim 6
Dependent Claim
62 words
A moving-coil type motor according to claim 1, including a sensor unit for detecting movement of said coil about said shaft, said sensor unit including a moving part mounted on the fore end of said arm member adjacent said coil for arcuate movement therewith and a fixed part disposed near the path of movement of said fore end of said arm member.
Claim 7
Dependent Claim
33 words
A moving-coil type motor according to claim 5, in which said coil and sensor unit moving part extend in opposite circumferential directions from said arm member and therewith form a substantially T-shaped configuration.
Claim 8
Dependent Claim
59 words
A moving-coil type motor according to claim 1, in which said magnetic circuit member includes an annular coil receiving recess which curves from its closed end to its open end along a circular arc centered on said shaft, said arm member being angularly offset from said magnetic circuit member, said angular offset being variable within a preselected angular range.
Claim 9
Dependent Claim
52 words
A moving-coil type motor according to claim 1, in which said longitudinally curved magnetic circuit member and longitudinally curved coil telescope angularly about the axis of said shaft, the extent of angular overlap of said longitudinally curved magnetic circuit member with said longitudinally curved coil being variable within a preselected angular range.
References Cited (Backward Citations)
US3440464A
Cited
US3659124A
Cited
US3751693A
Cited
US3743870A
Cited
US3813566A
Cited
US3816777A
Cited
US4079400A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-02-10 | 1984-08-11 | 1985-02-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-02-10 | 1988-08-11 | 1989-02-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-02-10 | 1992-08-11 | 1993-02-10 | $7700.00 | Window Closed / Lapsed |