Patent ID: 7090193
Filing Date: 2006-08-15
Classification: F16K

Abstract:
1. A butterfly valve in which a cylindrical flow passage is formed in the valve body such as to penetrate the valve body, a sheet ring made of elastic sealing material is mounted in the valve body, a disk-like valve element which comes into contact with and separates from the sheet ring is rotatably and pivotally supported by the sheet ring, a valve rod shaft supporting portion is formed in a radial direction of the valve body, the valve rod shaft supporting portion pivotally supports valve rods which pivotally support the valve element, an actuator is connected to an outer end of one of the valve rods, thereby driving and rotating the valve element, wherein a portion of the one valve rod which extends outward is pivotally supported, the valve shaft cylindrical portion which is connected to the valve rod shaft supporting portion is made of material different from that of the valve body, ends of the valve shaft cylindrical portion and the valve rod shaft supporting portion are formed into rectangular cylindrical recess and projection which are fitted to each other, a fitting projection and a fitting groove which fit to fitting surfaces of the valve shaft cylindrical portion and the valve rod shaft supporting portion are formed, a connection pin is driven into the fitting portions of the valve shaft cylindrical portion and the valve rod shaft supporting portion and they are connected to each other in a falling-out preventing state.