| 摘要 |
PURPOSE:To reduce the outside diameter of a zoom lens by forming a spring into an approximately arc shape along the outside circumference of a lens and extremely decreasing the depth required for housing the spring to a moving cylinder for holding the lens. CONSTITUTION:The moving cylinder 5 is constituted of a flanged cylinder consisting of a cylindrical 51 for holding the lens and a flange part 52 and cylindrical body 53 to be fitted into an L-shaped space between the two parts 51 and 52. Cam pin housing holes 7a are provided at 120 deg. intervals to the cylindrical body 53. A recess 12 for housing the arc-shaped spring 10 is annularly provided to the fitting surface of the cylindrical body 53 and the cylindrical part 51. After the spring 10 is fitted onto the cylindrical part 51, the cylinder 53 is fitted to the cylindrical part 51 and the cylindrical body 53 is integrally coupled by set screws to the flange part 52 to constitute the moving cylinder 5. A rectilinear cylinder 4 is fitted onto the moving cylinder 5 and cam pins 3 are inserted into the respective holes 7a through a rectilinear groove 14 and thereafter the cylinder 4 is fitted and assembled to a cam cylinder 1.
|
