I took apart a simple spray bottle to see how it kept the fluid flowing from the reservoir to the nozzle in only one direction. This can be done by using a simple check valve made of two pieces of plastic, a spring and a small ball. This is a simple way to solve difficult problems.
Unidirectional flow
It is often useful to restrict traffic in one direction. A simple use case is in a spray bottle. Let's consider a simplified spray bottle with three main components: a container for storing fluid, a storage area for the fluid to be sprayed, and a nozzle connecting it to the outer space where we are going to dispense fluid. We need to take the fluid out of the reservoir, put it into the grading area, and then distribute it to the outside.
Fluid sounds like a technical term, but in this case, it is an important term. Fluid refers to anything that flows, which means that its particles are not fixed. This means that both gas and liquid are fluids. We should pay attention to movable particles, because they are particles that move and push themselves.
The main user interface of the spray bottle is the trigger. This is a simple lever with a push rod that extends to the grading area. After pressing the trigger, it will push the fluid in the grading area and then flow out of the nozzle. After the trigger is released, the spring pushes it back, creating a vacuum effect, pulling the fluid out of the reservoir to the grading area, and continuing to circulate with the next trigger.
Why works like this
Two important things happened here. First, when the plunger applies pressure to the fluid, it can only move to the outside through the nozzle. If the fluid only returns to the water tank, we will have a simple machine to draw the water out of the water tank and push the water back. This is not very helpful.
Likewise, when the trigger is pulled out, it must refill the grading area from the reservoir (not from any liquid from the outside). For water spray bottles, the external fluid is air. If it refills with air in the work area, attempting to spray will only eject air out of the nozzle. This will also be a simple machine that sprays only a small amount of air. Again, not very helpful.
solve these problems
Both problems are solved by using a simple connection that allows the fluid to move in only one direction. If we place a reservoir between the reservoir and the reservoir, we will never have to worry about fluid returning from the reservoir to the reservoir. This solved our first problem. If we also put the nozzle in the nozzle so that the fluid can only move from the grading to the nozzle, then when the trigger is released, the air will never enter the grading area.
Very helpful. We can construct a very simple one-way connection using three main components: a ball, a spring, and a cylinder with a hole at one end.
The spring pushes the ball toward the circular hole. This means that any liquid on the spring side will not pass through the ball hole because the ball will block the ball. The pressure from the spring and any pressure from the fluid on the right will push the ball closer to the hole, ensuring that there is no room for fluid to flow to the left.
Now, let's use the plunger to apply pressure on the left side, which causes the fluid on the left side to push toward the ball. If the pressure is greater than the pressure from the right side (from the spring and the fluid from the right side), it will push the ball back, allowing some fluid from the left side to escape around the ball through the hole. Now, the fluid successfully flows from left to right. When we stop applying pressure, the pressure from the right side again dominates and pushes the ball tightly back into the hole, forming a seal.
Please note that we are talking about fluid pressure. The pressure may come from water, oil, air or any other fluid. The general concept of stress is the same for everyone; many small particles bounce on the surface.
If we can apply pressure on one side, we can make it under pressure so that our fluid flows in only one direction.
Let's create a one-way connection that allows flow from the transition area to the nozzle. When we push the water in the staging area, it will force the water to flow through the nozzle, but when we release the trigger, the air will not re-enter. Here, the force that pushes the spring to open the valve is the resulting pressure. Pull the trigger from.
We also want to ensure that fluids can only flow from the reservoir to the staging area. We also add a one-way connection there.
This also makes sense. When we relax the trigger, we want it to draw water from the reservoir, but when we push the same water, we don't want it to return to the reservoir. Here, the force that pushes the spring to open the valve is the pressure generated by the vacuum on the spring side.
With these two check valves, we can now precisely control the direction of fluid flow and can successfully spray water.
Check valve from nozzle. In which direction should the ball point?
What if we want to be able to open the valve manually? In fact, this is the principle behind the air valves on car and bicycle tires. Instead of a ball, a spring will force a specially shaped pin to form a seal. Part of the pin protrudes from the valve so that you can push it from the other side of the valve.