Patent ID: 7225677

Claim:
A pressure gauge, comprising: a body having an inlet, an outlet, and a shunt hole; a pressure meter assembled to the shunt hole; an inlet duct provided with a check valve, being assembled to the inlet of the body; and an outlet duct provided with an outlet, being assembled to the outlet of the body; wherein the check valve comprises a first cavity and a connected second cavity, the first cavity having a first through hole, the second cavity having a third through hole, a second through hole being defined between the first and second cavities, the first, second, and third through holes being aligned in a straight line, a shaft extending through the first, second, and third through holes, the shaft having opposite ends respectively forming a first flange corresponding in position to the first through hole and a valve corresponding in position to the third through hole, the shaft forming a second flange positioned in the second cavity, a spring arranged being the second flange and an inner wall surface of the second cavity.