The valve (10) has valve structure (12) guided in a stem guide lifting structure through a drive device (15) against a valve seat surface (18) of a valve seat ring in closed position or in opposite direction away from valve seat ring in an open position to...

A braking device of a DC motor (21) has a position detecting means (41) to detect a position of a motor shaft (29), a rotational speed detecting means to detect a rotational speed of the motor and a braking means (74) to generate a braking force based on a...