Manually push down the pressure handle, the volume in the spring cavity decreases and the pressure rises. The liquid enters the nozzle cavity through the hole of the valve core, and then sprays the liquid out through the nozzle. At this time, loosen the pressure handle and the pressure in the spring cavity The volume increases and negative pressure is formed. The sphere opens under the action of negative pressure, and the liquid in the bottle enters the spring cavity. At this time, there is already a certain amount of liquid in the valve body. When the handle is pressed again, the liquid stored in the valve body will be Punch upwards, spray out through the nozzle;
From the above working principle, the key to a good pump head is to pay special attention to the following places:
1. The glass ball or steel ball under the spring. The seal here is very important. It is related to the strength of the liquid in the spring cavity. If there is leakage, part of the liquid will leak into the bottle when the pressure handle is pressed. And affect the effect of liquid spray; 2. It is the sealing ring at the upper end of the valve body. If it leaks here, the upward force of the liquid will be reduced when the pressure handle is released, resulting in a small amount of liquid stored in the valve body, which will also affect the spray effect; 3 , The fit between the pressure handle and the valve core. If the fit here is loose and leaks, there will be a certain resistance when the liquid rushes up to the nozzle, and the liquid will flow back. If it leaks here, it will also affect the spray effect; 4. The design of the nozzle. The design of the nozzle is directly related to the spray effect. For details, please refer to the next page to explain the nozzle design in detail;
Therefore, the function of the general pump head is to detect these four positions, and other appearance and coordination problems are tested according to the routine;
