| 摘要 |
A twin-wheel castor comprises a moulded plastics body 1 and a pair of inset moulded plastics wheels 2. The body 1 has an upwardly open bore to receive a mounting spindle. The wheels 2 are respectively mounted on the ends of a steel spindle 4 which is a tight interference fit in a through bore 5 in the body moulding 1,with an end chamfer on the spindle providing a lead on assembly. A snap-on fixing of the wheels 2 on the ends of the spindle 4, with the wheels 2 free to rotate on the spindle 4, employs interengaging formations moulded in mounting bores 13 of the wheels 2 and formed by a rolling process on the metal spindle 4. Each such formation, both in the wheels 2 and on the spindle 4, comprises a peripheral projection in the form of an annular lip and an adjoining peripheral groove. <IMAGE> |
