摘要 |
A plunger barrel has a sliding bore in which a plunger is slid, a sleeve acceptor in the shape of a hole for a control sleeve which is formed in an intermediate portion of the sliding bore and a window portion which is opened in a wall defining the sleeve acceptor. The plunger barrel is manufactured by the steps of preparing a blank having one end portion and another end portion, forming a first bore axially from the one end portion of the blank, so as to provide a diameter equal to that of the sleeve acceptor, to an intermediate portion of the blank, drawing the one end portion of the blank so that a portion in which the sleeve acceptor is formed remains, forming a second sliding bore in the blank so as to penetrate from the one end portion to the other end portion of the blank, and forming a window portion in a wall of the sleeve acceptor. |