Patent ID: 6877715

Claim:
A vacuum regulating valve comprising: a valve body which has a first port and a second port connected to an upstream side and a downstream side of a fluid passage, respectively, and which has a communication passage between said first port and said second port; a valve plug which opens/closes said communication passage by being displaced in an axial direction of said valve body by a pressure fluid; and a nose provided on said valve plug and having a circumferential surface facing an inner wall surface of said first port, wherein said nose has an outer circumferential diameter which is smaller than an inner circumferential diameter of said inner wall surface, so that said nose is detachable from said valve plug through said first port connected to a vacuum chamber, and wherein said circumferential surface of said nose is provided with a straight section and a plurality of tapered sections having diameters gradually reduced in a displacement direction in which said valve plug is seated on a valve seat.