Abstract: A switching bearing assembly for a motor-driven spindle, e.g. a leadscrew adapted to drive a nut axially along the leadscrew, is provided with a bearing housing disposed between two fixed plates and biased centrally thereof by a plurality of compression springs. The housing is positioned to actuate switches which turn off the motor when the spindle bearing is overloaded, e.g. when the nut reaches the end of its travel or is otherwise impeded in its first axial movement. The housing is also provided with a spring-biased pin which bears upon an eccentric carried by the shaft to frictionally retard further rotation thereof once the motor has been turned off.