Patent ID: 8674573
Filing Date: 2014-03-18
Classification: B60L,B62M,H02K,Y02T

Abstract:
1. A direct-current motor comprising: a rotor having a rotation shaft; a stator surrounding the rotor; and a motor case that accommodates the stator and retains the stator, the motor case including a first case and a second case separable from each other in a direction of an axis of the rotation shaft of the rotor, the first case and the second case each having a separation edge extending around the stator; wherein the first case and the second case each have cut-away portions provided at angular positions circumferentially generally equidistantly spaced from each other and each extending parallel to the axis from the separation edge; wherein the separation edge of the first case and the separation edge of the second case each have abutment portions not formed with the cut-away portions, the abutment portions of the first case respectively abutting against the abutment portions of the second case; wherein the cut-away portions of the first case and the cut-away portions of the second case cooperatively define a plurality of windows that are disposed in a periphery of the motor case in circumferentially generally equidistantly spaced relation; wherein the stator has a plurality of bulges projecting radially outward from a peripheral surface thereof in association with the windows; wherein the bulges each have a fixing screw hole extending parallel to the axis for fixing the stator to the first case; wherein the first case has screw holes that are threadingly engaged with distal end portions of screws inserted through the fixing screw holes of the bulges; wherein the bulges are fitted in the windows, facilitating circumferential positioning between the stator and the motor case; wherein the motor case has a plurality of protuberances respectively provided around the windows and raised inward of the motor case; and wherein the protuberances abut against an outer peripheral surface of the stator.