Water stop valve

A water stop valve, comprising a valve body, a valve stein, a water plugging stopper, and a drive mechanism;

• a water inlet channel and a water outlet channel being formed in the valve body, a water sealing surface being disposed between the water inlet channel and the water outlet channel, the water sealing surface being in communication with the water inlet channel and the water outlet channel;
• a cavity being formed in the valve body above the water sealing surface, a mounting hole being formed in the valve body above the cavity;
• a middle portion of the valve stein being movably and sealedly mounted in the mounting hole, an upper portion of the valve stein extending out of the mounting hole and being connected to the drive mechanism, the drive mechanism driving the valve stein to move up and down, a back-pressure hole being formed in the water plugging stopper, a lower portion of the valve stein being movably mounted in the back-pressure hole of the water plugging stopper;
• the water-plugging stopper being disposed in the cavity, a water-passing gap being defined between the water-plugging stopper and the cavity, a back-pressure cavity being formed above the water-plugging stopper, the water-passing gap being in communication with the water inlet channel and the back-pressure cavity, the back-pressure cavity being in communication with the back-pressure hole, the back-pressure hole being in communication with the water outlet channel, a sealing end surface matching the back-pressure hole being formed on the valve stein;
• wherein when the valve stein moves upwards, the sealing end surface opens the back-pressure hole, and the water inlet channel is in communication with the water outlet channel to feed in water;
• when the valve stein moves downwards and drives the water plugging stopper to move downwards, the sealing end surface blocks the back-pressure hole, and the water plugging stopper blocks the water sealing surface, such that water enters the back-pressure cavity via the water-passing gap, and water pressure enables the water-plugging stopper to block the water sealing surface to stop the water.