| 摘要 |
An actuator is provided which comprises a cylinder within which are a piston (1), a piston rod (7) and a mechanical linkage arranged to transmit axial movement of the piston to the piston rod at a relative speed which decreases as the piston nears the end of its travel towards the piston rod. A rigid member constituted by a pivot disc (14) and link plates (16, 16a) is pivoted to the piston rod at a first pivot point. A link (17) is pivoted at a second pivot point (18) to the link plates and at its top end is pivoted to the piston (1). A pin (23) supported in the cylinder at an axial postion intermediate the piston and the piston rod end of the cylinder for transverse sliding movement is pivoted to or pivotally engageable within the disc (14) at a third pivot point. When the piston is at the far end of its travel from the piston rod the second and third pivot points respectively constituted by the pivot (18) and the pin (23) are both on the same side of the piston axis, whereas when the piston moves towards the piston rod, the second pivot point moves to the other side of the piston axis. In a preferred arrangement the pin (23) disengages with the disc (14) when the piston rod is at the far end of its travel. |
