| 摘要 |
A device, eg ball castor (11), providing multi-directional movement comprisi ng a housing (13) having at least one rolling member located partially their. e g ball (12) Bearing means comprising sets of ball bearings held in annular rac es transmit the load of a trolley, etc carried by the device to ball (12) and also act to centre ball (12). A brake having pad (22) is urged against the t op of ball (12) by a screw or spring to resist rolling movement of ball (12).</ SDOAB> |
