| 摘要 |
PROBLEM TO BE SOLVED: To provide a quantitative discharge device using a valve member which is of such a design that a sealing effect can be enhanced by giving a certain degree of freedom of making a displacement by outward expansion to the outside, with regard to the apex part which is slightly projectable from the outer circumferential surface of a piston body of an encircling seal of U-shape sectional form which constitutes an elastic seal member.SOLUTION: This quantitative discharge device operates with the help of a valve member on condition that an inner cylindrical body can be rotated by the drive force of a drive source and the extrusion actuator of the valve member can be removed from a drive actuating rod. In details, a stepped-shape notched part is circumferentially installed at the rear end part of the piston body of the extrusion actuator, and a male thread is formed at the rear end surface of the notched part. Further, an encircling seal with a U-shape sectional form, which has a notched part at the apex side and is equipped internally with an elastic ring capable of coming into contact under pressure with a perpendicular wall surface, is fitted into the notched part of the piston body. After these procedures, the perpendicular rear end surface of the encircling seal is screwed with the help of a ring-like hold-down tool which fits into the male thread, and the circumferential wall part of the encircling seal is displaced by outward expansion in inclined fashion, so that the apex surface of the circumferential wall part of the encircling seal, can slightly project from the outer circumferential surface of the piston body, using the elastic distortion of the elastic ring. |
