Valve

A valve comprising:

• a valve body that is formed therein with a fluid channel and a valve seat arranged in the fluid channel;
• a diaphragm that abuts and separates from a seat surface of the valve seat;
• a hollow bonnet that fixes a circumferential edge of the diaphragm to the valve body;
• a diaphragm presser that abuts the diaphragm and presses the diaphragm to the valve seat side;
• a lower stem that is formed with a male screw on an outer circumferential surface, the male screw being threaded to a female screw that is formed on an inner circumferential surface of the bonnet;
• and
• an upper stem, one end portion of which is engaged with the lower stem, and another end portion of which is projected from the bonnet and is engaged with an operation handle, wherein
• in an engagement section between the upper stem and the lower stem, either one of end surfaces is formed with a pair of fan-shaped abutment sections, and the other end surface is formed with a projected section, the projected section having:
• a pair of substantially fan-shaped missing sections, each of which has a longer arc length than a circular arc of the fan-shaped abutment section;
• and a
• vertical surface that makes surface contact with a planar lateral surface of the fan-shaped abutment section.

A hybrid valve comprising:

• a valve body that is formed therein with a fluid channel;
• and a valve seat arranged in the fluid channel;
• a diaphragm that abuts and separates from a seat surface of the valve seat;
• a hollow bonnet that fixes a circumferential edge of the diaphragm to the valve body;
• a diaphragm presser that abuts the diaphragm and presses the diaphragm against the valve seat side;
• and
• a piston that causes the diaphragm presser to move in an axial direction by a working fluid or pressing means, and a stem that causes the piston to move in the axial direction by a manual operation, the hybrid valve having:
• the piston having a piston body, a pressing shaft, and a working fluid introduction shaft, the piston body slidingly contacting an inner circumferential surface of a cylinder, and the pressing shaft extending both sides in the axial direction from the piston body;
• a stepped cylindrical intermediate body that is fixed to the bonnet and is formed with an engagement cylindrical section on an opposite bonnet side, the engagement cylindrical section having a smaller diameter than a bonnet fixed side;
• and
• a rotary body that is formed with a working fluid introduction hole, through which the working fluid is introduced to a circumferential surface fitted to the engagement cylindrical section, wherein
• the intermediate body is formed therein with a central through-hole, to which the working fluid introduction shaft is fitted, and a communication hole that connects an internal channel of the working fluid introduction shaft and the working fluid introduction hole.