I need to accurately control the movement of the cylinder piston image to the left and right, and I need to choose a double-acting single-piston cylinder.

I guess, the so-called "precise" control you need to move the cylinder piston left and right is probably that you need the cylinder to stop accurately while moving left and right. Now I just don't know how precise you need to be.

The answer is as follows:

1。 The moving direction and stopping (including locking) of the cylinder can only be controlled by the directional valve. In your case, the three-position five-way valve is a necessary choice, and there are three kinds.

Three-position five-way middle sealing solenoid valve (or air valve) closes the air inlet when it reaches the required position for movement, so as to maintain the air pressure in the chambers at both ends of the piston;

The three-position five-way middle release solenoid valve (or air valve) closes the air inlet and releases the air pressure in the cavities at both ends of the piston when the piston reaches the required position for movement;

Three-position five-way medium-pressure electromagnetic valve (or air valve), when it reaches the position required for movement, the switch keeps both ends of the piston entering the equal air pressure at the same time;

All three can achieve intermediate position stop. The first stop position is the most accurate; The second stop position takes the longest time and is the most unstable (because there is no air at both ends of the cylinder piston); The third stop position is the most stable (because both ends of the cylinder always maintain equal air pressure);

2.。 Stop precision (the "precision" you need). This is closely related to the form of the cylinder, the diameter of the cylinder, the moving speed of the cylinder, and the quality of the solenoid valve or gas valve. I want to know what your "accuracy" is. The specific physical examples are as follows:

. A. Ordinary double-acting cylinder, installed horizontally, with cylinder diameter D=32, pressure P=5, speed V= 150mm/s, solenoid valve with good quality and stop accuracy of about 4mm; It can be kept for 3~4 minutes, and will slowly move to the rod cavity at first;

B. Double-acting cylinder with locking, installed vertically, cylinder diameter D=80, pressure P=5, speed V=200mm/s, Japanese SMC three-position five-way sealed solenoid valve, vertical load 40Kg, positioning accuracy 3mm；; It can be kept for more than 3 minutes (it will be switched once at work); There is no change without loading heavy objects for more than 3 hours;

C. Ordinary double-acting cylinder, installed horizontally, with cylinder diameter D=32, pressure P=5, speed V= 150mm/s, Yadek solenoid valve (probably fake), and stopping accuracy of about 5mm; If it can be kept for 5-8 seconds, it will start to move slowly beyond the positioning range;

3。 Once again, the moving direction and stopping (including locking) of the cylinder can only be controlled by the directional valve at first. Others, such as two pins of single chip microcomputer control two directions respectively, magnetic induction switch control, combined device formed by arranging and installing pneumatic servo valves, etc. Electrical control is futile because only the valve can control the movement of gas in the cylinder.