A plate-like support has a pair of opposite faces and is formed with a throughgoing opening. A synthetic-resin lamp holder having a longitudinally open socket is formed with a foot projecting generally perpendicularly of the socket through the opening and formed with respective longitudinally spaced front and back abutments bearing on one of the faces of the support and respective side retaining formations between the abutments. A plug engaged snugly against the other face of the support between the abutments of the foot is formed with a pair of retaining formations lookingly engageable with the formations of the foot. An electrical wire extends through the plug, through the opening, and between the abutments to the socket.

The present invention vehicle light fixture comprises a hollow lens and a quick detachable socket. The hollow lens has a base permanently affixed at the bottom. The base has an opening thereto. A light bulb is installed in the quick detachable socket such that the detachable socket can be partially inserted into the opening and interlocks itself within the opening, thereby maintaining the light bulb within the hollow dome lens. To replace a malfunctioned light bulb, the detachable socket can be unlocked by rotating the socket which loosens itself from the opening at the base, and removed from the base so that the malfunctioned light bulb can be replaced with a new light bulb without the entire light fixture being replaced.

A pressure force adjusting mechanism for a vibration wave driven motor for applying a predetermined pressure force for frictionally driving an annular elastic member in which a travelling vibration wave is formed relative to a movable member is provided with a fixed support member for supporting the elastic member so as to have a degree of freedom in the axial direction thereof, a pressing member for pressing the elastic member from the axial rear thereof toward the movable member, and a holding member receiving the reaction force of the pressing member and fixedly fitted to the fixed support member. The holding member and the fixed support member are fixed by a projected portion which is formed on the holding member being engaged with the bayonet type engagement portion of the fixed support member. The engagement portion has its pressure force holding engagement surface against which the projected portion bears formed into an inclined surface inclined with respect to the axial direction.