Electromagnetic valve with shielding protective cover

Abstract

The utility model relates to the technical field of electromagnetic valves, in particular to an electromagnetic valve with a shielding protective cover, a shielding shell is made of pure copper materials, and due to the fact that copper has good conductivity, when electromagnetic waves meet the copper materials, induced current is generated on the surface of the shielding shell, and the shielding shell is called eddy current; the eddy current can generate an electromagnetic field opposite to an incident electromagnetic field, so that most incident electromagnetic waves are counteracted or reflected, penetration of electromagnetic energy is reduced, and in the high-frequency electromagnetic field, current tends to be concentrated on the surface of a conductor, which is a skin effect; due to the fact that the skin depth of copper is small, high-frequency electromagnetic waves are mainly conducted in a thin layer on the surface of the copper, electromagnetic energy is limited from spreading inwards, the shielding shell plays a role in preventing the electromagnetic energy from leaking outwards, the electromagnet, the piezoresistor and the TVS diode are connected in parallel, the electromagnet is subjected to two-stage protection, and the service life of the electromagnet is prolonged. And faults caused by damage of a single element are avoided.

Description

Technical Field

[0001] The utility model relates to the technical field of solenoid valves, and particularly relates to a solenoid valve with a shielding protective cover. Background Art

[0002] Nuclear power takes safety and reliability as the first principle. As the core component for controlling the valves of nuclear power plants, the safety and reliability of pneumatic actuators are particularly prominent. Therefore, as a dense reciprocating moving component, it is the most basic requirement to ensure its operation accuracy during long-term use.

[0003] Among nuclear-grade pneumatic actuators, only solenoid valves need to be powered on. According to the working characteristics of solenoid valves and the electromagnetic compatibility identification experience of linkage actuators, motors are prone to exceed the limit requirements during emission tests, and solenoid valves are prone to be broken down and burned out during surge tests.

[0004] Therefore, mainly for solenoid valves, it is necessary to increase shielding protection to prevent the leakage of electromagnetic energy, and at the same time increase the immunity to the environment, and add surge suppression measures to the solenoid valves to improve the tolerance to surge transients. At the same time, ensure the grounding of the whole machine and increase the bypass of electromagnetic interference signals, so that the solenoid valves are not affected by electromagnetic interference in the whole action process in nuclear power plants. Content of the Utility Model

[0005] (I) Technical Problems to be Solved

[0006] Aiming at the deficiencies of the prior art, the utility model provides a solenoid valve with a shielding protective cover, which solves the technical problems that the solenoid valve needs to increase shielding protection to prevent the leakage of electromagnetic energy, and at the same time increase the immunity to the environment, and add surge suppression measures to the solenoid valve to improve the tolerance to surge transients.

[0007] (II) Technical Solutions

[0008] To achieve the above purposes, the utility model is realized through the following technical solutions:

[0009] A solenoid valve with a shielding protective cover includes a shielding shell, an electromagnet, a varistor, a TVS diode, electrode plates, threaded electrode columns, a valve body, a valve core, a sealing ring, a magnet sheet, bolts, a ground wire access terminal and a power supply access terminal. The shielding shell is made of pure copper. The electromagnet is fixedly installed inside the shielding shell. The varistor is connected in parallel with the electromagnet through a wire. The TVS diode is connected in parallel with the electromagnet through a wire. The ground wire access terminal is fixedly installed at the side end of the shielding shell. Two power supply access terminals are fixedly installed at the top end of the shielding shell. Three electrode plates are respectively fixedly installed inside the ground wire access terminal and the power supply access terminal; the electrode plates are connected to the ends of the wires, and three threaded electrode columns are respectively threadedly installed inside the ground wire access terminal and the power supply access terminal.

[0010] Preferably, the valve body is fixedly installed at the side end of the shielding case through bolts, and the valve core is slidably installed inside the valve body.

[0011] Preferably, a plurality of sealing rings are fixedly installed on the valve core, and the magnet sheet is fixedly installed at the side end of the valve core.

[0012] (III) Beneficial effects

[0013] First, the shielding case is made of pure copper and completely wraps the electromagnet, which can isolate the electromagnetic fields inside and outside the shielding case, avoid the leakage of electromagnetic energy. At the same time, the shielding case is conducive to electroplating other metal materials to increase the corrosion resistance, achieving the effect of increasing the immunity to the environment.

[0014] Second, the varistor, TVS diode and electromagnet are connected in parallel with each other. The TVS diode has the advantages of fast response speed (usually in picoseconds), accurate clamping voltage, large power, low leakage current, etc. It can clamp the surge high voltage in the circuit at a safe level, and at the same time conduct the surge current to the ground. When an overvoltage higher than the threshold of the varistor appears in the circuit, its resistance rapidly decreases, clamping the overvoltage at a relatively fixed voltage value and absorbing a large current, thereby protecting the electromagnet and varistor connected in parallel with it. Both the varistor and TVS diode can protect the electromagnet, achieving the effect of improving the tolerance to surge transients. And when one of the components is damaged, the other can continue to protect the circuit, achieving the effect of improving the stability of surge suppression. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The above description is only an overview of the technical solution of the present invention. In order to be able to understand the technical means of the present invention more clearly and implement it according to the content of the specification, the following describes the preferred embodiments of the present invention in detail in conjunction with the drawings as follows.

[0016] Figure 1 is the structure diagram of the shielding case of the present invention;

[0017] Figure 2 is the cross-sectional structure diagram of the present invention;

[0018] Figure 3 is of the present invention Figure 1 amplified structure diagram at A;

[0019] Figure 4 is the cross-sectional structure diagram of the shielding case of the present invention;

[0020] Figure 5 is the circuit structure diagram of the present invention.

[0021] Legend: 1. Shielding case; 2. Electromagnet; 3. Varistor; 4. TVS diode; 5. Electrode plate; 6. Threaded electrode post; 7. Valve body; 8. Valve core; 9. Sealing ring; 11. Magnet sheet; 12. Bolt; 13. Ground wire access terminal; 14. Power supply access terminal. Detailed implementation

[0022] In the embodiment of the present application, by providing a solenoid valve with a shielding protective cover, the technical problems that the solenoid valve needs to increase shielding protection to prevent the leakage of electromagnetic energy, increase the immunity to the environment, and add surge suppression measures to the solenoid valve to improve the tolerance to surge transients are effectively solved. The shielding case is made of pure copper and completely wraps the electromagnet, which can isolate the electromagnetic fields inside and outside the shielding case, avoiding the leakage of electromagnetic energy. At the same time, the shielding case is conducive to electroplating other metal materials to increase the corrosion resistance, achieving the effect of increasing the immunity to the environment. The varistor and the TVS diode are connected in parallel with the electromagnet. The TVS diode has the advantages of fast response speed (usually in picoseconds), accurate clamping voltage, large power, and low leakage current. It can clamp the surge high voltage in the circuit at a safe level and at the same time conduct the surge current to the ground. When an overvoltage higher than the threshold of the varistor appears in the circuit, its resistance rapidly decreases, clamping the overvoltage at a relatively fixed voltage value and absorbing a large current, thereby protecting the electromagnet and the varistor connected in parallel with it. Both the varistor and the TVS diode can protect the electromagnet, achieving the effect of improving the tolerance to surge transients. And when one of the components is damaged, the other can continue to protect the circuit, achieving the effect of improving the stability of surge suppression.

[0023] Embodiment

[0024] As Figure 1 、 Figure 2 、 Figure 3 、 Figure 4 and Figure 5 shown, the technical solution in the embodiment of the present application effectively solves the technical problems that the solenoid valve needs to increase shielding protection to prevent the leakage of electromagnetic energy, increase the immunity to the environment, and add surge suppression measures to the solenoid valve to improve the tolerance to surge transients. The general idea is as follows:

[0025] In view of the problems existing in the prior art, the present utility model provides a solenoid valve with a shielding protective cover, including a shielding case 1, an electromagnet 2, a varistor 3, a TVS diode 4, an electrode plate 5, a threaded electrode post 6, a valve body 7, a valve core 8, a sealing ring 9, a magnet sheet 11, a bolt 12, a ground wire access terminal 13, and a power supply access terminal 14. The shielding case 1 is made of pure copper, and the electromagnet 2 is fixedly installed inside the shielding case 1.

[0026] The varistor 3 is connected in parallel with the electromagnet 2 through a wire, the TVS diode 4 is connected in parallel with the electromagnet 2 through a wire, the ground wire access terminal 13 is fixedly installed at the side end of the shielding case 1, the two power supply access terminals 14 are fixedly installed at the top end of the shielding case 1, and the three electrode plates 5 are respectively fixedly installed inside the ground wire access terminal 13 and the power supply access terminal 14; the electrode plates 5 are connected to the ends of the wires.

[0027] The three threaded electrode posts 6 are respectively installed inside the ground wire access terminal 13 and the power supply access terminal 14 by threading, the valve body 7 is fixedly installed at the side end of the shielding case 1 through the bolt 12, the valve core 8 is slidably installed inside the valve body 7, the plurality of sealing rings 9 are fixedly installed on the valve core 8, and the magnet piece 11 is fixedly installed at the side end of the valve core 8.

[0028] Working principle:

[0029] First step, during installation, insert the positive and negative poles of the two power supply wires into the corresponding power supply access terminals 14, then insert the ground wire into the ground wire access terminal 13, and then tighten the corresponding threaded electrode posts 6, then this device can be connected to the control system. The shielding case 1 is made of pure copper. Since copper has very good electrical conductivity, when electromagnetic waves encounter copper materials, induced currents will be generated on its surface, called eddy currents; these eddy currents will generate an electromagnetic field opposite to the incident electromagnetic field, thereby canceling or reflecting most of the incident electromagnetic waves, reducing the penetration of electromagnetic energy, and in high-frequency electromagnetic fields, the current tends to concentrate on the surface of the conductor, which is the skin effect; due to the small skin depth of copper, high-frequency electromagnetic waves are mainly conducted in a very thin layer on the surface of copper, thus restricting the propagation of electromagnetic energy to the inside, so that the shielding case 1 plays a role in blocking the leakage of electromagnetic energy. The shielding case 1 itself has a certain corrosion resistance, but corrosion may still occur in some specific environments. However, in dry air, copper is relatively stable. However, in environments with humidity and corrosive gases (such as sulfur dioxide, hydrogen sulfide, etc.), the surface of the shielding case 1 needs to be treated, such as tin plating, nickel plating, painting, etc.; due to the good electrical conductivity and ductility of the shielding case 1, it can uniformly receive the plating layer during the electroplating process and form a good bonding force with the plating layer, thereby improving the corrosion resistance.

[0030] In the second step, the TVS diode 4 is connected in parallel with the electromagnet 2. When a transient high-voltage pulse higher than the breakdown voltage of the TVS diode 4 appears in the circuit, the TVS diode 4 will quickly change from a high-resistance state to a low-resistance state, conduct, and divert the excessive current to the electrode plate 5 inside the ground wire access terminal 13, so that the large current is introduced into the ground wire, clamping the voltage at a safe level and protecting the electromagnet 2 at the back end from damage by excessive voltage. A varistor 3 is also connected in parallel between the TVS diode 4 and the electromagnet 2. Under normal operating conditions, the varistor 3 is in a high-resistance state and the current flowing through it is extremely small. When an overvoltage higher than the threshold value of the varistor 3 appears in the circuit, its resistance quickly decreases, clamping the overvoltage at a relatively fixed voltage value and absorbing a large current at the same time, thus protecting the electronic devices or circuits connected in parallel with it from damage by excessive voltage. The electromagnet 2, the varistor 3, and the TVS diode 4 are connected in parallel with each other, enabling the electromagnet 2 to be protected at two levels and preventing failures caused by the damage of a single component.

[0031] Finally, it should be noted that: Obviously, the above embodiments are only examples for clearly illustrating the present invention and are not limitations on the implementation manners. For those of ordinary skill in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation manners here. And the obvious changes or modifications derived therefrom still fall within the protection scope of the present invention.

Claims

1. A solenoid valve with a shielding protective cover, comprising a shielding shell (1), an electromagnet (2), a varistor (3), a TVS diode (4), an electrode plate (5), a threaded electrode post (6), a valve body (7), a valve core (8), a sealing ring (9), a magnet sheet (11), a bolt (12), a ground wire access terminal (13) and a power supply access terminal (14), characterized in that, The shielding case (1) is made of pure copper. The electromagnet (2) is fixedly installed inside the shielding case (1). The varistor (3) is connected in parallel with the electromagnet (2) through a wire. The TVS diode (4) is connected in parallel with the electromagnet (2) through a wire. The ground wire access terminal (13) is fixedly installed on the side end of the shielding case (1). The two power supply access terminals (14) are fixedly installed on the top end of the shielding case (1). The three electrode plates (5) are respectively fixedly installed inside the ground wire access terminal (13) and the power supply access terminal (14). Among them, the electrode plate (5) is connected to the end of the wire.

2. The solenoid valve with a shielding protective cover according to claim 1, characterized in that, The three threaded electrode posts (6) are respectively threadedly installed inside the ground wire access terminal (13) and the power supply access terminal (14).

3. The solenoid valve with a shielding protective cover according to claim 1, characterized in that, The valve body (7) is fixedly installed on the side end of the shielding case (1) through bolts (12).

4. The solenoid valve with a shielding protective cover according to claim 1, characterized in that, The valve core (8) is slidably installed inside the valve body (7).

5. The solenoid valve with a shielding protective cover according to claim 1, characterized in that, A plurality of sealing rings (9) are fixedly installed on the valve core (8).

6. The solenoid valve with a shielding protective cover according to claim 1, characterized in that, The magnet piece (11) is fixedly installed on the side end of the valve core (8).

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