Electric motor and manufacturing method of electric motor
AssigneeKitashiba Electric Co., Ltd.
InventorHiroshi Shirasaka
Life of this patent
Estimating the term…
Abstract
There is provided an electric motor and a manufacturing method of the electric motor capable of joining a brush and a commutator without placing load on components. An electric motor is formed at a side of a brush holder 13 with a second notch unit 32, and a groove unit 36 is formed on a brush 12 so that it overlaps the second notch unit 32 in the position where the brush 12 stored in the brush holder 13 does not abut against a commutator 8. By doing so, when joining the brush 12 and the commutator 8, the brush 12 may be temporarily fixed with respect to the brush holder 13 by pushing in the brush 12 in the brush holder 13 and coinciding the second notch unit 32 and the groove unit 36, and fixing a jig and the like to the groove unit 36 in this state.
Claims3
An electric motor equipped with a yoke which accommodates a rotor, and a bracket with a rear end coupled to the yoke and a front end coupled to an external surface of an engine case accommodating an engine operation unit, in which an output shaft of the rotor penetrates the bracket and extends into the engine case, comprising:
- a commutator provided on an outer periphery of the output shaft of the rotor for applying voltage to the rotor;
- a pair of columnar brushes which abuts against the commutator at one end thereof;
- a pair of tubular brush holders provided at a rear side of the bracket for storing the brush;
- and
- a pair of biasing elements which bias the brush stored in the brush holder to the commutator side;
- wherein the brush holder, in a state where the bracket is fixed to an assembling tool with an edge-shaped jig descending to a position positioned preliminarily, with a rear side of the bracket being the upper surface, has a slit-shaped notch unit formed at a position corresponding to the position to which the jig descends at an upper side surface of the brush holder, and
- the brush has a concave groove which is formed so as to overlap the notch unit at a position in which the brush stored in the brush holder does not abut against the commutator, and to which the jig is fitted.
A manufacturing method of an electric motor equipped with a yoke which accommodates a rotor, a bracket with a rear end coupled to the yoke and a front end coupled to an external surface of an engine case accommodating an engine operation unit, an output shaft of the rotor which penetrates the bracket and extends into the engine case, a commutator provided on an outer periphery of the output shaft for applying voltage to the rotor, a columnar brush which abuts against the commutator at one end thereof, a bottomed tubular brush holder provided at a rear side of the bracket for storing the brush, and a biasing element which biases the brush stored in the brush holder to the commutator side;
- comprising:
- a first step of inserting a coil spring as the biasing element to the brush holder provided on the bracket, in a state where the bracket is fixed to an assembly tool with an edge-shaped jig descending to a position positioned preliminarily, with a rear side of the bracket as the upper surface;
- a second step of coinciding a slit-shaped notch unit formed at an upper side surface of the brush holder corresponding to a position on which the jig descends, with a concave groove formed on a brush stored in the brush holder so as to overlap the notch unit at a position of the brush in which the brush does not abut against the commutator, and to which the jig fits;
- and
- a third step of fixing the brush by descending the jig in a state where the notch unit and the concave groove are coincided, and fitting the jig to the concave groove.
Dependencies are inferred from the claim text.