One kind of wheel motors directly connected with the tractor, because they do not use the gear box, hence the name no gears. Governor - (1) a mechanical speed control equipment. The elevator, this is a rope used to brake the centrifugal traction device. It will lead to car safety device. When the elevator down to the speed exceeds a predetermined value, it will start the power switch and check the elevator. (2) in terms of the escalator, which is a direct effect of the centrifugal device, when the escalator speed when the power and braking.
