| 摘要 |
PURPOSE:To improve the assembling properties and maintainability and to prevent an electrostatic noise by a method wherein nesting projection parts are provided on a nose, a rear cover is abutted against a heat radiator, and a spring small raised part provided on an arm of a fixed spring is abutted against an inner wall step of the radiator. CONSTITUTION:In the loading of a radiator 7 on a head body 10, an inner wall of the radiator 7 is shaped into a cylinder circumscribing a frame 1, and one or more cutout parts 7b for positioning the radiator 7 with respect to a nose 8 are provided on one end face 7a of the radiator 7 which is vertical to the direction of the shaft center of a head. The same number of projection parts 8b to be nested are provided also on the nose 8. An abutting part 7d to abut a rear cover 14 against the radiator 7 is provided. On the other hand, any of one or more spring small raised parts 6a provided on two or more arms 6c of a fixed spring 6 is abutted against a step 7c provided on the inner wall of the radiator 7. In this manner, assembling properties and maintainability can be improved, and an impact dot head free from an electrostatic noise can be obtained. |
