DIAPHRAGM ACTUATOR AND SECONDARY AIR CONTROLLER

摘要

PROBLEM TO BE SOLVED: To reduce the number of parts required for connecting a rod and a diaphragm mutually and suppress changes of an effective area of the diaphragm to obtain stable characteristic in a diaphragm actuator having integrally a ringlike nipped part, a disclike rod connection part arranged coaxially with the nipped part, and an annular connection part connecting inner periphery of the nipped part and outer periphery of the rod connection part mutually and having a mountain shape rising on one side in the axial direction in a natural condition to connect one end of the rod with the rod connection part of the diaphragm making both faces face a first pressure chamber and a second pressure chamber. SOLUTION: One end of the rod 35 is mold-connected with the rod connection part 31b of the diaphragm 31, and a vertex P of the annular connection part 31c which has the mountain shape in the natural condition is arranged at a position closer to a nipped part 31a side than the center between the inner periphery of the nipped part 31a and the outer periphery of the rod connection part 31b.