Patent ID: 9108474
Filing Date: 2015-08-18
Classification: B60C,F16K,G01L,Y10T

Abstract:
1. A relief-valve device for an air pressure gauge comprising: a casing having a relief-valve assembly mounted in the assembling hole of the discharging member of the casing and having a valve shaft mounted axially slidably in the relief-valve assembly and selectively located at a released position or a pressed-down position relative to the discharging member and the valve seat, and having wherein when the valve shaft is located at the released position relative to the discharging member and the valve seat, the second seal ring airtightly contacts a portion of shaft member, and the third seal ring airtightly contacts the mounting cover and the valve head to close and prevent the valve hole from communicating with an external atmosphere; when the valve shaft is located at the pressed-down position relative to the discharging member and the valve seat, the second seal ring aligns contactlessly with the discharging notch of the shaft member, and the third seal ring separates from the mounting cover such that the valve hole, the discharging notch, the air passageway and the external atmosphere communicate with one another.