| 摘要 |
A counter-balancing mechanism is provided that includes a support for supporting an article to be tilted about a horizontal axis, and an annular cam movable with the support, wherein the cam has a cam surface which varies in height in a direction normal to the plane of rotation of the support. A cam follower is loaded by a resilient member, whereby, as the support rotates, the cam follower and resilient member cause a return force to be exerted on the cam surface to substantially counteract the torque caused by the rotation of the support. A reaction member for varying the return force in accordance with a load on the support is provided, wherein the cam is able to rotate about its own axis which is offset from the axis of rotation of the support, and wherein the reaction member includes a variable reaction point, against which the cam follower force reacts, at or offset from the axis of rotation of the support, thereby to cause the return force exerted due to rotation of the support about a particular angle to be varied. |
