| 摘要 |
<p>PURPOSE: To perform four-wheel steering with a simple constitution and select one among a variety of traveling states by changing only the gear ratio of a gear assembly by a method wherein a four-wheel steering mechanism includes a motor as a driving source, a speed reducing gear mechanism, first and second motion converting devices, a cam and a steering bar. CONSTITUTION: When a motor 13 is operated in the normal direction according to control inputs, a front wheel tie rod 4 is moved in a specified direction between the left and right directions by a speed reducing gear mechanism 14 and a first motion converting device 19, and front wheels 1 are changed from the frontal direction to the specified direction via the tie rod 4, a knuckle arm 3 and a king pin 2. A second motion converting device 20 converts the amount of rotation on a horizontal axil of the speed reducing gear mechanism 14 to an amount of rotation on the horizontal axil at a specified angle corresponding to a specified gear ratio set in the speed reducing mechanism 14. A steering lever 24 is swung a specified amount by the rotation on the horizontal axil. Therefore, a rear wheel tie rod 8 pivoted on the steering lever 24 is moved in a specified direction between the left and right directions or in both directions corresponding to the swing amount of the steering lever 24, so that rear wheels 5 are changed from the frontal direction to a direction between the left and right directions or both directions.</p> |
