Motorized seat adjustment device for motor vehicle, has screw`s shoulder comprising safety thread with pitch identical to and synchronized with pitch of screw`s part, and nut`s thread engaged with safety thread when nut is engaged with part

摘要

#CMT# #/CMT# The device has an electric motor (7) for actuating a driving screw connected with a nut (15). The screw has a part (9v) with a pitch different from a pitch of another part (9c). The part (9v) varies linear displacement speed of the nut on the screw in a predetermined manner based on relative position of the nut on the screw. The screw has a shoulder (9e) comprising additional safety thread with a pitch identical to and synchronized with the pitch of the part (9c). The nut has an internal thread engaged with the safety thread when the nut is engaged with the part (9c). #CMT#USE : #/CMT# Motorized device for longitudinally adjusting a seat (claimed) of a motor vehicle with respect to a floor pan of the vehicle. #CMT#ADVANTAGE : #/CMT# The arrangement of the device permits fine adjustment of position of the seat at low speed and at variable high speed. The arrangement of the safety thread enables improvement of resistance against high external efforts such as traction, wrenching or compression efforts, thus enabling the seat to conserve the adjusted position irrespective of high external efforts. The device is reliable and permits obtaining speed variation in a simple, inexpensive and robust manner. #CMT#DESCRIPTION OF DRAWINGS : #/CMT# The drawing shows a lateral elevational view of an angular position adjustment mechanism actuated by a motorized seat adjustment device. 7 : Electric motor 9c, 9v : Driving screw`s parts 9e : Shoulder 15 : Nut 17 : Seat element.