An automatic bar-loader for lathes including a channel for feeding of a bar to the lathe mandrel and a bar-pusher powered by an electric motor controlled by a control unit and having a head collet for grasping the tail of a bar in the channel to make it run therein. The data processing circuitry is operative to receive multiple samples of the input signal, and to determine a first value at least in part by multiplying each of the samples by respective ones of a first set of values for an impulse response and summing the results. The stapler also includes a manually adjustable depth adjuster for adjusting a depth of drive of the fasteners. When the seat base has been rotated from its nominal position, the carriage will generally be prevented from being released from the elongate positioning member. When a vehicle-body speed is smaller than a predetermined quick pressure reduction prohibiting speed, the ECU performs a quick pressure reduction prohibiting control to restrain a quick pressure reduction having a greater reduction amount than a predetermined reduction amount. The simulated signal and the processed photodiode signal are compared so as to generate a control signal for controlling modulation amplitude of the laser device and hence the extinction ratio.