To prevent unpleasant sound generated in brake operation by press- fitting a bush formed with a synthetic resin coating layer on the inner peripheral surface, into each engaging part of an armature to slidably fit the bush to the outer peripheral surface of a support member fixed to a field core.
A brake spring 10 interposed between the field core 1 and the armature 5 is accommodated in each spring hole 1d of the field core 1, and a brake disc 7 is clamped between a side plate 3 and the armature 5 by the spring force of the brake spring 10 to place a rotating shaft in a braking state. An electromagnetic coil 2 is excited to magnetically attract the armature 5 to a pole face 1b of the field coil 1 along a support member 4 through a bush 6 to release braking of the brake disc 7. In this case, a coating layer formed of a synthetic resin material is provided on the inner peripheral surface of the bush 6 to prevent unpleasant sound (backlash sound) caused by micro vibration generated between the armature 5 and the support member 4.
HAGIWARA HIROSHI
TAKAHASHI TSUNEHITO
SAITO YOSHIKAZU
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