The cylinder is used so much, do you really understand how the cylinder works? 【dynamic picture】

Foreword:

The cylinder is used so much, do you really understand how the cylinder works? So here, the editor of Shenwei will tell you about the practical application of the working principle of the cylinder. I believe that after reading this article, your confidence in using the cylinder will become stronger and stronger!







The actuator in the picture above has a variety of actions. Let’s take the most commonly used basic cylinder as an example to see what’s inside.

Basic structure of cylinder
The so-called pneumatic actuator is an element that uses compressed air as power to drive the mechanism to perform linear, swing and rotational movements.
Take the most commonly used basic cylinder as an example to see what's inside.






So here comes the question. I wonder if you can tell if it is a single-acting cylinder or a double-acting cylinder after looking at the picture above?



Classification of cylinders

Single acting cylinder:
The single-acting cylinder piston only supplies air to one side. The air pressure pushes the piston to generate thrust and then returns by spring or its own weight.



Just like, even if you are single, you can still go to the squash court and have a good time. Because the squash ball will bounce back to you.






Double acting cylinder:
The double-acting cylinder uses air pressure on both sides of the cylinder piston to achieve forward or backward movement.

So, change it to another one, and it becomes – you are lucky to have found your goddess and you can now play badminton with her.







Cylinder buffer

However, the cylinder also has a problem. If a buffer device is not used, when the piston reaches the end of its movement, especially for a cylinder with a long stroke and a fast speed, the kinetic energy of the piston hitting the end cover will be very large, which can easily damage parts and shorten the life of the cylinder. .
What's more, the noise caused by the impact is also quite terrible. If the noise of a cylinder without a buffer device is 70dB, the noise of the entire factory will be as high as 140dB, just like being on a jet runway for a long time. This has reached the limit of human intolerability and unbearable pain.

How to solve these problems? Our designers made a buffer design for the cylinder.

1Hydraulic buffer
The first and simplest method of cylinder buffering is to install a hydraulic buffer at the front end of the cylinder.




All joking aside, we still have to say something serious. The following is a diagram of the working principle of hydraulic buffering:





Through the unique damping hole design, mineral oil is used as the medium to smoothly realize the transition from high-speed light load to low-speed heavy load.
Features: A wide range of energy levels from small to large without the need for adjustment, allowing for optimal energy absorption.

2 rubber buffers
In order to install it more compactly in the factory, designers thought of another method, the second method: rubber buffering. (Buffer pads are provided at both ends of the piston rod)



Precautions:
1) The buffering capacity is fixed and unchangeable, and the buffering capacity is small. It is mostly used in small cylinders to prevent operating noise.
2) It is necessary to pay attention to deformation, peeling and other phenomena caused by rubber aging.

3 air buffers
The third method: air buffering. (When the piston moves, the buffer sleeve and sealing ring work together to form a closed air chamber/buffer cavity on one side to achieve buffering.)



The gas in the buffer chamber can only be discharged through the buffer valve. When the opening of the buffer valve is very small, the pressure in the cavity rises rapidly, and this pressure generates a reaction force on the piston, thereby decelerating the piston until it stops.

Precautions:
1) The buffering capacity is adjustable by adjusting the opening of the buffer valve. The smaller the opening, the greater the buffering force.
2) Cushioning is achieved by utilizing the back pressure during cylinder operation. The cylinder back pressure is small. Buffering capacity will also be smaller. When using, attention must be paid to the control method of load rate and cylinder speed.

Magnetic switch
At this point, we know how the cylinder moves freely. But everything has rules, and so does the movement of the cylinder. Have they all gone into place? Did you cross a line? Who should supervise this?
Magnetic switch - it is a feedback signal to determine whether the cylinder is running in place, and controls the corresponding solenoid valve to complete the switching action.
Principle: The magnetic ring moving with the piston approaches or leaves the switch, and the current in the switch is magnetized.