| 摘要 |
<p>A mirror is mounted in the open end of a circular housing by means of a universal joint formed by a stud which projects from the rear of the mirror into a spherically-shaped knuckle joint that is seated at diametrally opposite sides in a pair of "Teflon"* ring bearings carried by two plates that are held over opposite sides of the knuckle by a pair of adjusting screws which can be selectively tightened or loosened to control the resistance to movement of the mirror universally about the center of the joint. The housing is releasably attachable to the hub cap of a front wheel by a plurality of clamps adjustably mounted on arms which project radially from the housing. In use pressure can be applied to the face of the mirror, during rotation of the wheel, to effect coarse adjustment of the mirror into an operating position normal to the axis of rotation of the wheel, and when the wheel is stopped, fine adjustment of the mirror can be effected by screws that are mounted on the housing around the periphery of the mirror. *A REGISTERED TRADEMARK</p> |
