| 摘要 |
A castor wheel assembly for chairs and the like is disclosed in which the wheel axle and hub are permitted a limited vertical stroke in a slot, a vertically arranged spring being active against the peripheral surface of the axle so that, when the chair is unloaded, the springs of the wheels urge the latter down so that the hubs may engage a friction surface. When the user seats on the chair, the springs are compressed and the rotation of the wheels is unhindered. The total force of the springs in a chair shall overcome the chair's own weight. |
