US 4,035,677 A · Rotor of a micro motor

Abstract

In a rotor of a micro motor, a magnet is indirectly attached to a rotor shaft by means of a pair of bushes without using any adhesive material. The pair of bushes comprises upper and lower bushes which are respectively mounted by means of an interference fit around the rotor shaft. Each bush comprises a cylindrical portion in the center of which a hole is formed, and a flange portion having around its periphery an annular notched portion. The notched portion of the upper bush is formed on a lower surface of the flange portion adjacent to the outer periphery of the cylindrical portion while the annular notched portion of the lower bush is formed on an upper surface of the flange portion adjacent to the outer periphery of the cylindrical portion, and due to the notched portions, each flange portion is provided with a certain degree of resiliency. The magnet is loosely fitted over the outer periphery of the cylindrical portions of the respective bushes and disposed between the flange portions thereof so that it is clamped between the flange portions of the bushed by means of the resiliency of the flange portions and thereby fixed between both bushes.

Claims7

Dependent claims

A rotor structure of a micro motor for use with timepieces and the like comprising:

a rotor shaft;
an upper bush and a lower bush connected to said rotor shaft and extending in axially spaced relationship therealong, each bush comprising a cylindrical portion having a hole in the center thereof through which extends said rotor shaft, a flange portion connected to said cylindrical portion at the end thereof remote from the other bush, and means rendering said flange portion resilient to a certain degree with respect to the axial direction of said rotor shaft;
and a magnet having a hole therein disposed around the cylindrical portions of both said upper and lower bushes and being resiliently clamped at opposite ends between the flange portions of said upper and lower bushes thereby fixing said magnet relative to said rotor shaft by the resiliency of said flange portions and without use of adhesive.

Dependencies are inferred from the claim text.

Rotor of a micro motor

Life of this patent

Rotor of a micro motor

Life of this patent

Abstract

Claims7