Patent ID: 9709209
Date: 2017-07-18
CPC Classifications: B66F,F16M

Claim:
1. A load supporting device comprising: a supporting member for supporting a load, capable of being moved within a predetermined range along a predetermined direction; a spring member whose one end is fixed and another end applies a biasing force to the supporting member against the load in a direction along a moving direction of the supporting member; a cam follower; a first cam surface that abuts against the cam follower to transmit the load to a spring member side and that is inclined with respect to the biasing force direction; a second cam surface that abuts against the cam follower to transmit the biasing force to a supporting member side and that is inclined with respect to the biasing force direction; a third cam surface that abuts against the cam follower and is inclined with respect to the biasing force direction; a first side supporting portion that generates, at the first cam surface, a reaction force against the load that restricts a displacement of the first cam surface in a direction perpendicular to the biasing force direction; and a second side supporting portion that generates, at the second cam surface, a reaction force against a biasing force that restricts a displacement of the second cam surface in the direction perpendicular to the biasing force direction, wherein a pressing force of the third cam surface against the cam follower includes a first direction component along a direction of the biasing force generated depending on a position in the predetermined range over which the supporting member can be moved and a second direction component perpendicular to at least the biasing force direction, and the first cam surface, second cam surface, and third cam surface are designed such that in the predetermined range over which the supporting member can be moved, the load, biasing force of the spring member, pressing force of the third cam surface against the cam follower, a reaction force of the first side supporting portion against the first cam surface, and a reaction force of the second side supporting portion against the second cam surface are in equilibrium about the cam follower.