Height adjustment mechanism for seat headrest of motor vehicle, has locking arm including lower excrescence to exert locking effort on opposite sides of pin, where pin has micro-denture opposite to excrescence and on height adjustment zone

摘要

The mechanism has two pins (21', 22') parallel to each other such that a headrest slides along axial direction on the pins. A locking arm immobilizes the pins in the axial direction. The locking arm has a lower excrescence arranged for exerting locking effort on diametrically opposite sides of each pin in a locking position. The pin has a micro-denture (6) opposite to the lower excrescence and on a height adjustment zone (H). The pins have metal cores (213, 223) covered with plastic materials (214, 224), respectively.