Parking lock device

摘要

A rotation of a right wheel (3RR) and a rotation of a left wheel (3RL) of a vehicle are locked respectively by independent parking lock mechanisms (6). Each parking lock mechanism (6) comprises a locking operation prevention mechanism (63c,63d) which mechanically prevents the locking operation of the parking lock mechanism (6) when a wheel rotation speed exceeds a predetermined parking lock prevention wheel rotation speed. The controller (CU, 10) is programmed to prevent the locking operation of the parking lock mechanisms (6) of the right and left wheels (3RR, 3RL) when a predetermined parking lock permitting condition based on wheel rotation speeds of the right wheel (3RR) and the left wheel (3RL) is not satisfied, thereby preventing a state in which one of the right and left wheels (3RR, 3RL) is prevented from rotating while the other is not prevented from rotating.

主权项

1. A parking lock device for a vehicle having a right wheel and a left wheel, comprising:
a right parking lock mechanism which locks a rotation of the right wheel, the right parking lock mechanism comprising a locking operation prevention mechanism which mechanically prevents a locking operation of the right parking lock mechanism when a wheel rotation speed of the right wheel exceeds a predetermined parking lock prevention wheel rotation speed; a left parking lock mechanism which locks a rotation of the left wheel, the left parking lock mechanism comprising a locking operation prevention mechanism which mechanically prevents a locking operation of the left parking lock mechanism when a wheel rotation speed of the left wheel exceeds the predetermined parking lock prevention wheel rotation speed; a rotation speed sensor which detects a wheel rotation speed of the right wheel; a rotation speed sensor which detects a wheel rotation speed of the left wheel; and a programmable controller programmed to execute the following steps when a shift lever of the vehicle shifts to a parking range:
determining if a predetermined parking lock permitting condition is satisfied on the basis of the wheel rotation speed of the right wheel and the wheel rotation speed of the left wheel;preventing the locking operation of both of the right parking lock mechanism and the left parking lock mechanism when the predetermined parking lock permitting condition is not satisfied; anddetermining that the predetermined parking lock permitting condition is not satisfied when a difference between the wheel rotation speed of the right wheel and the wheel rotation speed of the left wheel is greater than a predetermined speed difference.