因为饮水机用有两种供水桶 Because water fountains use two kinds of water bottles 一种由供水站供水的纯净水桶（上面没口）和另一种是用自来水带过滤芯的供水桶（上面开口便于添加自来水）。 A clean bucket (no mouth) supplied by water supply stations (above) and another is a water tank with tap water, which can be used to add tap water. 第一种水桶的供水原理在简单不过了，学过初中物理的都知道。如瓶中的水之所以能倒出来是因为在倒水的同时有空气不断进入瓶中，只要瓶中的气压不小于瓶外的气压，水就，如果瓶中的气压小于瓶外的气压，水就会在瓶外的气压作用下阻止其流出。只要控制流入瓶中的空气就能控制水的流出，而这个办法就是利用水自身的密封能力。在饮水机放置水桶的下方还有个类似水盆的装置，当桶中的水流到盆中，并且水上升到刚好淹没到桶口，此时流入桶中的空气被阻断，桶内气压不能变化了，此时水就不会再从桶中流出，直到当水盆中的水下降，不在淹没桶口，空气又可进入，水又可流出，最后就这样重复。对于这种桶在上面开口的话等于是将桶外与桶内的气压拉通相等，这时桶内的水就会不受控的在引力的作用下流出来了。只有下面的桶才可以上面开口，因为它有水阀。 The water supply of the first bucket is as simple as it is, and you know the physics of junior high school. Like a bottle of water can be poured out because there is air in the water at the same time continue to come into the bottle, as long as the pressure in the bottle does not less than the pressure of the bottle, water, and if the air pressure is less than the bottle of bottle of air pressure, air pressure outside the water in the bottle under the action of preventing the outflow. As long as the air flowing into the bottle controls the flow of water, the solution is to use the water's own sealing capacity. Put down to the bottom of the bucket has a similar basin in water dispenser device, when the bucket of water into the basin, and water to rise to just flooded the barrel mouth, into the bucket in the air is blocked, at this time in barrel pressure can not change, the water comes out of the barrel will no longer, until when the water in the water drops, not submerged bucket mouth, air can enter again, water can flow out again, then repeat. For this kind of bucket in the above talk so the pressure within the barrel outside and barrel's equal, then the water in the bucket is not controlled in the downstream of gravity. Only the bottom bucket can be opened above because it has a water valve. 第二种桶则是利用浮力驱动锥形水阀控制桶中的水流出。也是当水盆中的水升的一定高度时带锥形水阀的浮球就会在浮力的作用下关闭桶的出水口。另外水盆中的水位越高，侵入水中的浮球面积也越多，浮球受到的浮力也越大，浮力越大作用于锥形水阀的力越大（相当于阀门关的越死）。还有一种是一方有开口另一方封闭的圆柱体，在封闭方连上锥形水阀的控水装置。由于开口按装于下方，当水盆中的水位上升并挤压半封闭圆柱体内的空气，然后在被挤压空气的反作用力下推动半封闭圆柱体向上，并带动锥形水阀关闭出水口。 The second bucket USES the buoyancy drive cone water valve to control the flow of water from the barrel. It is also when the water in the basin is raised that the float of the tapered valve will close the bucket by the buoyancy effect. And the higher the water level in birdbath, invades the floating ball in the water area is, the more the more float by the buoyancy of the, the greater the buoyancy effect on the greater the force of water cone valve (valve of the dead). Another is a cylinder that has a closed cylinder, which is connected to a conical water valve in the closed side. Due to open in the lower part, when the water level went up in the basin and squeeze the semi-closed air in the cylinder, and then under the reaction of squeezed the air pushing semi-closed cylinder upward, and drive the cone water closed the valve outlet.