Detailed explanation of several positions of solenoid valve

"Tong" and "Position" are important concepts of pneumatic reversing solenoid valve. Different "on" and "position" constitute different types of pneumatic reversing solenoid valves. Generally speaking, "two-position valve" and "three-position valve" mean 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 the two, three, and four of the valve body of the reversing valve are not connected and can be connected to different oil pipes or gas in the system Interface, different oil passages / gas paths can only be communicated through the valve switch when the spool is displaced

      The previous "several positions", if you want to see the working status of this valve, it can be said as several positions. If there is a pneumatic component symbol, it is better understood. The square on the icon represents the valve body (there is an arrow in it) (Or T line). The "pass" in the back means that there are several points on one of the squares (the points that intersect with the arrow line and the T line), which is the pass.

      The meaning of the graphic symbols is generally as follows:

     (1) Use a box to indicate the working position of the valve. A few boxes indicate how many "bits";

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

     (3) The symbol "┻" or "┳" in the box indicates that the path is not accessible;

     (4) If there are several interfaces connected to the outside of the box, it means that they are “passive”;

     (5) In general, the oil inlet / air inlet of the valve and the system oil supply or gas connection is indicated by the letter p; the oil return / air return of the valve and the system oil return / air connection is t (sometimes o) The port / air port where the valve is connected to the actuator is indicated by a, b, etc. Sometimes the leakage port is represented by 1 on the graphic symbol;

     (6) The directional 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 neutral position in the graphic symbol is the normal position of the three-position valve. The two-position valve using a spring return is the normal state of the channel in the box close to the spring. When drawing the system diagram, the oil / gas path should generally be connected to the normal position of the directional valve.