| 摘要 |
PROBLEM TO BE SOLVED: To restrain the deterioration in ride-comfort by influence of inertia.SOLUTION: In a compression stroke, a ball screw shaft 31 relatively moves in the upper direction to an electric motor 50, and an upper end surface 32b of a ball screw nut 32 abuts on a flat surface 60cp of a rotor 60. Thus, rotation of the ball screw nut 32 is transmitted to the rotor 60. In an extension stroke, a lower end surface 32c of the ball screw nut 32 abuts on an upper surface of a first spur gear 71. Thus, rotation of the ball screw nut 32 is transmitted to the rotor 60 via the first spur gear 71, a second spur gear 72 and a rotor internal gear 73. Thus, in both of the compression stroke and the extension stroke, since the rotor 60 rotates in the same direction, inertia force of the rotor 60 is reduced. |
