What is a solenoid valve, what is a solenoid valve, the electrical symbol of a solenoid valve

What is a solenoid valve? What is a solenoid valve? A solenoid valve is an industrial equipment controlled by electromagnetism. It is particularly common in industrial machine control and industrial valves. It can control the direction, flow, speed and other parameters of the medium to achieve control. Valve switch control. Solenoid valves can cooperate with different circuits to achieve desired control, and can also ensure control accuracy and flexibility. Solenoid valves are basic components of automation used to control fluids and are actuators;not limited to hydraulics and pneumatics. Solenoid valves are used to control the direction of hydraulic flow. The mechanical equipment in the factory is generally controlled by hydraulic steel, so solenoid valves are used. There is a sealed cavity inside the solenoid valve. There are through holes at different positions. Each through hole leads to a different oil pipe. There is a valve in the middle of the cavity and two electromagnets on both sides. When the solenoid coil on which side is energized, the valve body will be attracted to which side. By controlling the movement of the valve body, different oil drain holes will be blocked or leaked, while the oil inlet hole is normally open, so the hydraulic oil will Entering the different oil drain pipes, the oil piston then drives the piston rod through oil pressure. In this way, the mechanical movement is controlled by controlling the current of the electromagnet. The electrical symbol of the solenoid valve is as shown in the figure: The solenoid valve symbol refers to a schematic diagram describing the function of the solenoid valve. It is usually used in pneumatic system design and product identification to help pneumatic system designers and solenoid valve users understand product functions. During the design process, it is often necessary to look at the gas circuit diagram. Various solenoid valves appear on the drawings as their corresponding pneumatic symbols. This representation is the solenoid valve symbol. The "number" in front depends on how many working states the valve has. It can be said that it is several. If there is a pneumatic component symbol, it will be easier to understand. On the icon, it represents the square of the valve body (with arrows or arrows inside). T line) There are as many as there are. The following "several connections" represent several points on one of the squares (points that intersect with the arrow line and T line), which are several connections. The meaning of the graphic symbol of the solenoid valve: 1. Use a box to indicate the working position of the valve. The number of boxes indicates how many "positions" there are;2. The arrow in the box indicates that the oil circuit is connected, but the direction of the arrow It does not necessarily indicate the actual direction of the liquid flow;3. The symbols "┻" or "┳" in the box indicate that the passage is blocked;4. The number of interfaces connected to the outside of the box indicates how many are "open";5. Generally , the oil inlet/air inlet connected to the system oil supply line or gas line is represented by the letter p;the oil return/air return port connected to the system oil return line/gas line is represented by t (sometimes o);and The oil/air ports connecting the valve and the actuator are represented by a, b, etc. Sometimes l is used on the graphic symbol to represent the leakage port;6. The reversing valve has two or more working positions, one of which is the normal position, which is the position of the valve core when it is not subject to control force. The middle position in the graphic symbol is the normal position of the three-position valve. The two-position valve that uses a spring to return the valve takes the passage state in the box close to the spring as its normal position. When drawing a system diagram, the oil/gas circuit should generally be connected to the normal position of the reversing valve. Representation methods of solenoid valve symbols in different application industries: 1. Process industry In the flow chart (PID diagram) with control points in the process industry, the graphical symbol of the solenoid valve is shown in Figure 1. Figure 1 Solenoid valve symbol on the PID diagram 2. Mechanical industry In the mechanical industry or mechatronics pneumatic and hydraulic transmission systems, the graphic symbols used are as shown in Figure 2, a two-position three-way solenoid valve, arranged up and down and arranged left and right. Symbol diagram. Figure 2 Schematic diagram of the solenoid valve graphic symbol: the upper and lower boxes are not two cavities, but represent the state of energization and non-energization respectively. The upper box (left box) represents the direction and port of fluid flow after energization. , the box below (box on the right) represents the direction and port of fluid flow when no power is supplied. In this dual-state drawing method, the pipeline connections are drawn without power, that is, in the lower box (right box). The numbers 1, 2, and 3 in the figure adopt the domestic and international numerical designation method, as well as the letter designation method. Specific markings: the air inlet is 1 or P, the exhaust port is 5 or R, the exhaust port is 3 or S, the working port is 2 or A, and the working port is 4 or B. Others 12, 14, 82, and 84 belong to the pilot section. The box of the icon represents the working position of the solenoid valve, and the number of boxes indicates the number of "positions". The arrow within the box indicates that the fluid is connected, but the direction of the arrow does not necessarily indicate the actual direction of the fluid. A T-shaped symbol in a box indicates that the path is blocked. The number of interfaces connected to the outside of the box indicates how many "connections" there are. Generally speaking, the two-position two-way, two-position three-way, two-position four-way, and two-position five-way are based on the above. The reversing valve has two or more working positions, one of which is the normal position, that is, the valve plug is not in the