The solenoid valve is an industrial equipment controlled by solenoid, an automatic basic element for fluid control, and an actuator. The pneumatic solenoid valve is one of them. It blocks or leaks different oil drain holes by controlling the movement of the valve body. The oil inlet hole is normally open, and the hydraulic oil will enter different oil drain pipes, and then push the piston of the oil cylinder through the pressure of the oil in the pneumatic solenoid valve, In this way, the mechanical movement of the entire solenoid valve is controlled by controlling the current of the solenoid of the pneumatic solenoid valve.

How many positions and channels is the pneumatic solenoid valve?

The pneumatic solenoid valve has many openings and positions according to its functions and needs. There are two position two-way, two position three-way, two position five way, two position four-way and solenoid valve. (Two position five way and two position four-way are divided into single electric control and double electric control).

Yes: three position five way; Three position five way solenoid valve also includes three position five way solenoid valve for middle seal, three position five way solenoid valve for medium pressure, three position five way solenoid valve for middle discharge and three position four way solenoid valve. There are also four position five way solenoid valves (three solenoid heads) with special requirements.

Of course, the simplest and most commonly used are the two position three-way solenoid valve and the two position five way solenoid valve. If the cylinder (actuator) needs to stop in the middle, use the three position five way solenoid valve.

Detailed explanation of several positions and connections of solenoid valve:

Pass "and" position "are important concepts of pneumatic directional solenoid valve. Different types of pneumatic directional solenoid valves are formed by different "on-off" and "position".

Generally speaking, the "two position valve" and "three position valve" refer to that the spool of the reversing valve has two or three different working positions. The so-called "two-way valve", "three-way valve" and "four-way valve" refer to that there are two, three and four interfaces on the valve body of the reversing valve which are not connected with each other and can be connected with different oil pipes or gas pumps in the system. The front "several positions" can only be connected between different oil/gas channels through the switch of the valve port when the valve core is shifted. If you want to see how many working states the valve has, you can say it is several positions. If there is a symbol of pneumatic components, you can better understand it, The number of the square representing the valve body (with arrows or T lines inside) on the symbol is several. The "several passes" in the back represents the number of points on one of the squares (the point where the arrow line and T line intersect), which is called "several passes".

The meanings of graphic symbols are generally as follows:

(1) A box is used to indicate the working position of the valve, and several boxes are used to indicate the number of "positions";

(2) The arrow in the box indicates that the oil circuit is connected, but the arrow direction does not necessarily indicate the actual direction of liquid flow;

(3) The symbol "-" or "field" in the box indicates that the access is blocked;

(4) The number of interfaces connected outside the box indicates the number of connections;

(5) Generally, the oil inlet/air inlet connecting the valve with the system oil supply circuit or air is indicated by the letter p; The oil/gas return port connected between the valve and the system oil/gas return circuit is represented by t (sometimes o); The oil port/air port connecting the valve and the actuating element is indicated by a, b, etc. Sometimes, it is used on the graphic symbol to indicate the leaking oil port;

(6) The reversing valve has two or more working positions, one of which is the normal position, that is, the position where the valve core is not subjected to the operating force. The middle position in the graphic symbol is the normal position of the three position valve. The two position valve that uses spring return takes the channel state in the box close to the spring as its normal position. When drawing the system diagram, the oil/gas circuit should generally be connected to the normal position of the reversing valve.

On off, five way is provided with five channels for ventilation, one of which is connected with the air source, two of which are connected with the air inlet and outlet of the external air chamber of the double acting cylinder, and two of which are connected with the air inlet and outlet of the internal air chamber. The specific working principle can be referred to the working principle of the double acting pneumatic actuator: in terms of the air circuit (or liquid circuit), the two position three-way solenoid valve has one air inlet (connected to the air source), one air outlet (provided to the air source of the target equipment) 1 exhaust hole (generally a muffler is installed, and it can be omitted if it is not afraid of noise).

The two position five way solenoid valve has one air inlet (connected to the air supply), one positive acting air outlet and one negative acting air outlet (respectively provided to the air supply of one positive and one negative acting for the target equipment), one positive acting air outlet and one negative acting air outlet (with muffler installed). For small automatic control equipment, 8~12mm industrial rubber gas pipe is generally selected as the gas pipe. Electrically, the two position three-way solenoid valve is generally single electrically controlled (i.e., single coil), and the two position five way solenoid valve is generally double electrically controlled (i.e., double coil). The coil voltage class generally adopts DC24V, AC220V, etc. The two position three-way solenoid valve is divided into normally closed type and normally open type. The normally closed type means that the air circuit is disconnected when the coil is not energized, and the normally open type means that the air circuit is connected when the coil is not energized.

The action principle of the two position five way double electric control solenoid valve: if the positive action coil is energized, the positive action air circuit is connected (there is air in the air hole when the positive action is made). Even if the positive action coil is de energized, the positive action air circuit is still connected, and it will remain until the negative action coil is energized. If the reaction coil is powered on, the reaction air circuit is connected (there is air in the reaction air hole). Even if the reaction coil is powered off, the reaction air circuit is still connected and will remain until the positive coil is powered on. This is equivalent to "self-locking". Based on this characteristic of the two position five way double electric control solenoid valve, when designing the electromechanical control loop or compiling the PLC program, you can make the solenoid valve coil act for 1~2 seconds, which can protect the solenoid valve coil from damage.