An Experimental Case Study
In this chapter, the friction-induced vibration of the lead screws incorporated in the horizontal drive mechanism of a type of powered seat adjuster is studied. The horizontal drive mechanism is constructed of two parallel lead screw slider systems. Torque is transmitted from a DC motor to the two lead screws through worm gearboxes. Flexible couplings connect the gearboxes to the motor and to the two lead screws. The nuts are stationary and are connected to the seat frame. The lead screw sliders together with the motor and gearboxes move with the seat as the lead screws advance in the nuts. In some cases, an extra force applied (by the passenger) in the direction of motion causes the system to generate audible noise, which is unacceptable to the car manufacturer.