The phenomenon of this failure is that after the exhaust valve is closed, the rubber ball is used to pressurize, and the pressure is always on. When the ball is pinched, the pressure is lifted. When the pinch is released, the mercury column comes down again, or after the pressure is applied, it stops. Pressurized, the mercury column drops quickly.
The method of maintenance is to fold and compress the rubber tubes from the rubber ball to the mercury storage bottle and from the mercury storage bottle to the armband airbag respectively after the pressurization. Observe whether the mercury continues to fall, and eliminate the leak-finding part by section. . If the rubber bag leaks, it should be replaced; if the rubber ball unit leaks, check the ball end check valve or exhaust valve leak, otherwise it should be replaced; if the rubber valve leaks, can rubber ball Divide from the exhaust valve: screw-fastened, after opening, you can see a small section of the rubber tube similar to the bicycle tire valve core; dial-type, after removing the ball, but also from the exhaust valve Take out such a section of valve core, use your fingers to move the rubber tube, you can find a crack on both sides, if there is wool flocculation in the crack, pressuring, when loosening the ball, the crack can not be closed, just hit the The mercury column will come down again. The dirt in the cracks is cleaned, and the resulting air leakage problem can be eliminated.