Abstract: To provide a valve that is easily assembled and has a low possibility of breakage of a coupled section even when the valve has to be downsized or subjected to a large load. A valve has a valve unit and a drive unit, is configured to include: a first recess that is a recess formed in either one of a second stem or a first stem and is formed with a groove at a predetermined position on an inner circumferential surface of the recess; a second recess formed in another one thereof; a stem pin accommodated in both of the recesses; an urging member that is accommodated in the first recess and urges the stem pin to the other side; a sidewall through-hole that penetrates a sidewall of the second recess horizontally; and a ball that enters the sidewall through-hole.

Abstract: To provide a diaphragm and a diaphragm valve which solve a problem of deterioration of air-tightness due to insufficient tightening of a bolt and damage to the diaphragm due to over-tightening of the bolt, as well as reducing variations in performance such as durability of the diaphragm and simplifying tightening work. A diaphragm is provided with a through hole having a diameter larger than a diameter through which a bolt can be fitly inserted. A bolt insertion cylinder made of metal through which the bolt can be inserted is fitted in the through hole. A height of the bolt insertion cylinder is equal to or less than a height of the through hole.