| 摘要 |
PURPOSE:To improve the operation sense of a photographer by forming an outer cylinder and an inner cylinder which are fitted or screwed to a middle cylinder, to a sandwitch-shaped forming structure consisting of a skin layer and a core layer, selecting a material having a good sliding property as a resin material of the skin layer, and using a material which can secure the strength, as a resin material of the core layer. CONSTITUTION:A middle cylinder 2 used as a forming use die member, as well, and an outer cylinder 4 and an inner cylinder 6 are formed as one body at the same time. Especially, by forming the outer cylinder 4 and the inner cylinder 6 for rotating relatively against the middle cylinder 2, to a forming structure of a sandwich structure, a surface resin material for sliding with the middle cylinder 2 becomes a material having a good affinity of the slidability against the middle cylinder material, and as for structure material, a glass fiber contained resin whose strength is excellent can be formed, and a lens barrel which is excellent in its strength and slidability is obtained. For instance, in case a metal, for instance, aluminum has been used in consideration of a fact that the middle cylinder 2 is used as a forming use die member, in case it has been seen as a lens barrel unit of a three layer structure of the outer cylinder, the middle cylinder and the inner cylinder, it can be contributed in order to secure the dimension accuracy at the time of forming the outer cylinder and the inner cylinder, and as a result, a lens barrel having a high lens movement accuracy can be obtained. |
