| 摘要 |
PROBLEM TO BE SOLVED: To contrive not to form the outside of a barrel cylinder thick even when a grip member is formed on the barrel cylinder, and in addition, prevent a peeling off or a positional slip or the like of the grip member from occurring as far as possible by a method wherein at a gripping area of the barrel cylinder, the grip member is formed integrally together with the barrel cylinder as in the manner of a two-color molding or an insert-molding. SOLUTION: At an area to be gripped of a barrel cylinder 1, a grip member 13 made of an elastic material is integrally formed on the barrel cylinder 1 by a procedure of a two-color molding or an insert-molding. For the grip member 13, a material which is easily welded to the barrel cylinder 1 is selected. Then, due to being easy to weld, even when the grip member 13 is thinly molded, a peeling off and a positional slip to the barrel cylinder 1, are prevented from occurring. In addition, the grip member 13 is not formed to the front end part of the barrel cylinder 1, but a location which is slightly retracted from the front end part is made the front end part of the grip member 13. That is, at the front end of the grip member 13 of the barrel cylinder 1, a flange part 17 is formed, and the outer diameter of the flange 17 is formed to be the same as the outer diameter of the front end of the grip member 13, or slightly larger. |
