Printed coil unit for small size actuator
First Claim
1. A printed coil unit for an actuator of a small size comprising at least one printed coil sheet having opposed planar surfaces separated by a defined thickness;
- a magnet magnetized so as to present at least one magnetic pole in a given plane, said printed coil sheet being disposed in opposition to said magnet and having at least one spiral conductor pattern deposited in said plane,wherein at least one magnetic sensor element having a thickness smaller than said defined thickness of said printed coil sheet, is formed in a region of said printed coil sheet located in the vicinity of and outside of said spiral conductor patterns, said magnetic sensor element being confined within the exposed surfaces of said printed coil sheet.
1 Assignment
0 Petitions
Accused Products
Abstract
A printed coil unit for use in a very thin type flat brushless motor or a linear actuator, in which a magnetic sensor element having a thickness smaller than 0.6 mm is embedded integrally within the coil unit without projecting therefrom in a region located outside and in the vicinity of spiral conductor coil patterns. The printed coil unit includes a single printed coil sheet or a lamination of such coil sheets each having more than one spiral conductor patterns on the same plane. A magnetic sensor element, such as Hall element or magneto-resistance element having a thickness equal to or smaller than that of the printed coil sheet is embedded within the coil sheet at blank regions located between adjacent spiral conductor patterns, or regions made availably by diminishing the size of a selected one of the spiral conductor patterns. A moving speed detecting coil or patterned conductor can be additionally provided on the other available area of the coil sheet.
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Citations
15 Claims
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1. A printed coil unit for an actuator of a small size comprising at least one printed coil sheet having opposed planar surfaces separated by a defined thickness;
- a magnet magnetized so as to present at least one magnetic pole in a given plane, said printed coil sheet being disposed in opposition to said magnet and having at least one spiral conductor pattern deposited in said plane,
wherein at least one magnetic sensor element having a thickness smaller than said defined thickness of said printed coil sheet, is formed in a region of said printed coil sheet located in the vicinity of and outside of said spiral conductor patterns, said magnetic sensor element being confined within the exposed surfaces of said printed coil sheet. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10)
- a magnet magnetized so as to present at least one magnetic pole in a given plane, said printed coil sheet being disposed in opposition to said magnet and having at least one spiral conductor pattern deposited in said plane,
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11. A flat brushless motor of a small size comprising a printed coil unit composed of a lamination of a plurality of disc-shaped printed coil sheets each having a plurality of spiral conductor patterns, said lamination constituting a stator;
- a magnetic yoke member for supporting said printed coil unit disposed thereon;
a disc-shaped magnet disposed in opposition to said coil unit with a small cap between said magnet and said conductor pattern, said magnet being uniformly magnetized with alternating poles in the circumferential direction and serving as a rotor; and
a rotatable supporting shaft for supporting said magnet and said yoke member at respective centers,wherein said magnet has n paired magnetic poles arrayed in the circumferential direction and has an inner diameter r1 and an outer diameter r2, each of said printed coil sheets being provided with a row of 2n spiral conductor patterns disposed circumferentially, at least one of said printed coil sheets having opposed planar disc surfaces and a magnetic sensor element disposed in said printed coil sheet with a magneto-sensitive portion of said sensor element located in opposition to said magnet at a position within a region lying outside of said spiral conductor patterns at a distance R given by the range r1 ≦
R≦
r2 ×
1.1 from the center of said magnet, said magnetic sensor element being enclosed within a notch formed in said one printed coil sheet, said sensor element being confined between the planes determined by the opposed surfaces of said one printed coil sheet. - View Dependent Claims (12, 13, 14, 15)
- a magnetic yoke member for supporting said printed coil unit disposed thereon;
Specification