| 摘要 |
A device for switching an electric motor, particularly for braking an electrically operated tool, comprises change-over switches 19' and 20' for connecting and disconnecting the electric motor to and from an associated power source, for reversing the polarity of a field winding or armature winding of the electric motor, and for enabling and disabling an electric braking circuit for the electric motor, also an actuating member 21' for the change-over switches 19', 20', a movable contact 32', which is associated with each change-over switch and is movable between a fixed ON contact 30' and an OFF contact 30, which is spaced an arcproof distance from said ON contact, and a sliding guide 40', which is associated with at least one movable contact 32' and is adapted to guide said movable contact over at least part of its path of movement during the switching operation. The actuating member consists of a switching slider 21', which cooperates with a toggle lever 54. Tension springs 60 linked to the toggle lever engage at their other end a pivoted lever 27' for moving the movable contact 32'. During the movement of the toggle lever 54 the springs 60, 61 are extended and are pivotally moved beyond a neutral position defined by the hinge 42' for the pivoted lever 27 so that a sudden switching operation is performed.
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