High-performance radio frequency switch with full-shielding coaxial structure

Abstract

The invention discloses a high-performance radio frequency switch with a full-shielding coaxial structure, which comprises a shielding box body, a plurality of coaxial transmission line assemblies, a plurality of radio frequency reeds arranged in a shielding groove and an electromagnetic driving device, and is characterized in that the shielding box body is made of a metal material, and the shielding groove and a plurality of vertical holes vertically communicated with the shielding groove are formed in the shielding box body; each coaxial transmission line assembly is installed in the corresponding vertical hole, one end of each coaxial transmission line assembly penetrates out of the upper portion of the shielding box body to form an internal radio frequency contact, and the other end of each coaxial transmission line assembly penetrates out of the lower portion of the shielding box body to form a bottom radio frequency port used for achieving vertical interconnection with a user radio frequency board. Through the design of the shielding box body, external electromagnetic interference is effectively shielded, and the stability of radio frequency signals in the switch is ensured. The vertical interconnection with a user radio frequency board is realized by adopting the coaxial transmission line assembly, the impedance matching problem of a high frequency band is reduced, the frequency upper limit and the application frequency upper limit of the switch are improved, and the millimeter wave frequency band can be reached.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of electrical switches, in particular to a high-performance radio frequency switch with a full-shield coaxial structure. BACKGROUND

[0002] In today's communication and electronic technology field, microwave mechanical switches play a crucial role. With the rapid development of technology, various electronic devices are constantly moving towards miniaturization and high performance, which puts higher and higher requirements on the performance and size of microwave mechanical switches. Microwave mechanical switches are widely used in radar, communication base stations, satellite communication and many other fields, and their performance directly affects the working efficiency and stability of the entire system. A high-quality microwave mechanical switch can ensure accurate transmission and switching of signals, thereby ensuring the normal operation of the equipment. In modern communication systems, the demand for high-speed data transmission and complex signal processing is increasing, which requires microwave mechanical switches to have higher frequency response and lower loss to adapt to the increasing technical challenges.

[0003] In order to reduce the size and volume of microwave mechanical switches, related technologies often use microstrip transmission lines in the radio frequency part, and use a half-hole side structure for the radio frequency interface. For example, in related technologies, the circular coaxial transmission line and rectangular transmission line part of the traditional radio frequency mechanical switch are replaced by a microstrip surface of a coplanar waveguide structure. This method changes the structure of the transmission line and the form of the interface to some extent, reducing the size of the switch. Some switches also optimize the internal circuit layout and use integrated design to further reduce the size. These methods are common technical measures in the industry in pursuit of miniaturization.

[0004] However, these existing technical means have obvious defects. Poor impedance matching at high frequencies is a major problem, which limits the performance of the switch when used at high frequencies. The upper limit frequency of the switch itself is difficult to improve, and the upper limit frequency of the application is also low, which cannot meet the requirements of some high-frequency performance applications such as millimeter wave communication and radar systems. SUMMARY

[0005] In order to solve the technical problems in the prior art, the present application provides a high-performance radio frequency switch with a full-shield coaxial structure.

[0006] The high-performance radio frequency switch with a full-shield coaxial structure provided by the present application adopts the following technical solution: A high-performance radio frequency switch with a full-shield coaxial structure, comprising: A shielded box body made of a metal material, having a shielded slot and a plurality of vertical holes vertically communicating with the shielded slot inside; a plurality of coaxial transmission line assemblies, each of the coaxial transmission line assemblies is installed in a corresponding vertical hole, one end of each of the coaxial transmission line assemblies penetrates through the top of the shielding box to form an internal radio frequency contact, the other end of each of the coaxial transmission line assemblies penetrates through the bottom of the shielding box to form a bottom radio frequency port for vertical interconnection with a user radio frequency board; a plurality of radio frequency reeds arranged in the shielding groove, the radio frequency reeds are movable conductors; an electromagnetic driving device for driving at least one of the radio frequency reeds to move, so as to selectively connect or disconnect the internal radio frequency contacts of the plurality of coaxial transmission line assemblies, thereby achieving switching of a radio frequency signal path.

[0007] In some embodiments, the shielding box comprises a middle block, a top plate and a bottom plate, an upper surface of the middle block forms the shielding groove, the shielding groove is annular, the vertical holes are arranged in the middle block and penetrate through the upper and lower surfaces of the middle block, the top plate is fixed to the upper surface of the middle block to close the shielding groove, and the bottom plate is fixed to the lower surface of the middle block to close each of the vertical holes.

[0008] In some embodiments, the high-performance radio frequency switch of the fully shielded coaxial structure further comprises a reset mechanism, the reset mechanism comprises a reverse spring and a fixed medium, the reverse spring has a fixed end and a plurality of movable ends, the fixed end is fixed to the top plate, each of the movable ends is connected to a corresponding radio frequency reed through the fixed medium, and the movable ends are driven by the electromagnetic driving device.

[0009] In some embodiments, a first non-circular anti-rotation hole is arranged on the reverse spring, a second non-circular anti-rotation hole is arranged on the radio frequency reed, a clearance hole is arranged on the top plate, one end of the fixed medium is fixedly inserted into the first non-circular anti-rotation hole, and the other end of the fixed medium is fixedly inserted into the second non-circular anti-rotation hole after penetrating through the clearance hole.

[0010] In some embodiments, the fixed end is fixed to the top plate via at least one fixed block.

[0011] In some embodiments, each of the movable ends forms a force arm, and the electromagnetic driving device comprises a plurality of electromagnetic driving members, each of the electromagnetic driving members is used to drive a corresponding force arm to move.

[0012] In some embodiments, the electromagnetic driving member is an electromagnetic coil, the electromagnetic coil is fixed to the top plate and located above a corresponding force arm, the force arm is magnetically coupled to the electromagnetic coil, and the electromagnetic coil can be powered on or powered off to attract or release the corresponding force arm.

[0013] In some embodiments, a plurality of through holes are formed in the bottom plate and coaxially communicated with the vertical holes, the lower end of each of the coaxial transmission line assemblies passes through a corresponding through hole, and a patch is fixed to the lower end of each of the coaxial transmission line assemblies and arranged on the lower surface of the bottom plate.

[0014] In some embodiments, the number of coaxial transmission line assemblies is four, and the four coaxial transmission line assemblies are respectively used to connect different channels of the user radio frequency board.

[0015] In some embodiments, the high-performance radio frequency switch of the full-shield coaxial structure further comprises: a microcontroller; at least one position sensor for monitoring the position of the radio frequency reed (3); and at least one temperature sensor for monitoring the working temperature; The microcontroller is connected with the position sensor, the temperature sensor and the electromagnetic drive device (4) respectively, and is configured to: receive the position feedback signal of the position sensor to perform closed-loop control on the electromagnetic drive device (4), so as to accurately adjust the contact state of the radio frequency reed (3); and receive the temperature feedback signal of the temperature sensor to perform preset temperature compensation or warning action.

[0016] In summary, the present application has at least one of the following beneficial technical effects: 1. By designing the shielding box, the external electromagnetic interference is effectively shielded, and the stability of the internal radio frequency signal of the switch is ensured. The vertical interconnection with the user radio frequency board is realized by using the coaxial transmission line assembly, which reduces the impedance matching problem of the high frequency band, improves the upper limit of the frequency and the application frequency of the switch itself, and can reach the millimeter wave frequency band; 2. The electromagnetic drive device drives the radio frequency reed to move, realizes the switching of the radio frequency signal path, and the reset mechanism ensures the reset of the radio frequency reed, so that the switch can work stably and reliably. Compared with the prior art, the present switch significantly improves the high-frequency performance on the basis of miniaturization, and meets the demand of modern communication and electronic equipment for high-performance microwave mechanical switch; 3. By integrating the microcontroller and the sensor, the closed-loop control of the switch state and the temperature monitoring are realized. This not only ensures the accuracy and reliability of the switch action, but also realizes the fault prediction and health management (PHM), and improves the working stability and power tolerance of the switch in high-power and complex temperature environment, so that it becomes an intelligent sensing and execution node. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1is a perspective structural schematic view of a high-performance RF switch with a full shielding coaxial structure provided by an embodiment of the present application; Figure 2 is Figure 1 is a perspective structural schematic view of a high-performance RF switch with a full shielding coaxial structure in the Figure 3 is Figure 1 is a perspective structural schematic view of a high-performance RF switch with a full shielding coaxial structure in the Figure 4 is Figure 1 is a perspective structural schematic view of a coaxial transmission line assembly and a RF reed in the Figure 5 is Figure 4 is a perspective structural schematic view of a RF reed in the Figure 6 is Figure 4 is a perspective structural schematic view of a rebounding reed in the Figure 7 is Figure 1 is an exploded view of a shielding box and a RF reed in the Figure 8 is Figure 7 is an exploded view of a shielding box in the Mark explanation: 1, shielding box; 11, middle block; 111, shielding groove; 112, vertical hole; 12, top plate; 121, let go of the hole; 13, bottom plate; 131, through hole; 2, coaxial transmission line assembly; 21, internal RF contact; 22, bottom RF port; 23, patch; 3, RF reed; 31, second non-circular anti-rotation hole; 4, electromagnetic drive device; 41, electromagnetic drive piece; 5, reset mechanism; 51, rebounding reed; 511, fixed end; 512, movable end; 5121, force arm; 513, first non-circular anti-rotation hole; 52, fixed medium piece; 53, fixed block. DETAILED DESCRIPTION

[0018] The technical solutions in the embodiments of the present application will be further described in detail below with reference to the drawings. The described embodiments are only possible technical implementations of the present application, but are not limited thereto, and those skilled in the art can obtain other embodiments without creative labor under the circumstances of the embodiments of the present application.

[0019] The present application mainly uses a micro coaxial RF interface to realize vertical interconnection, which achieves the effect of improving the upper limit of switch frequency to the millimeter wave frequency band. The present application will be described in further detail below.

[0020] Embodiment 1

[0021] The high-performance radio frequency switch of the full shielding coaxial structure provided by the embodiment of the application comprises a shielding box body 1, a plurality of coaxial transmission line assemblies 2, a plurality of radio frequency reeds 3 and an electromagnetic driving device 4, wherein the shielding box body 1 is made of metal material and can shield external electromagnetic interference to ensure stable transmission of internal radio frequency signals. The plurality of coaxial transmission line assemblies 2 are respectively installed in vertical holes 112 of the shielding box body 1, one end of each of the coaxial transmission line assemblies 2 forms an internal radio frequency contact 21, and the other end forms a bottom radio frequency port 22, which can be vertically connected with a user radio frequency board. The radio frequency reed 3 is a movable conductor and is arranged in a shielding groove 111. The electromagnetic driving device 4 can drive the radio frequency reed 3 to move to connect or disconnect the internal radio frequency contact 21 of the coaxial transmission line assembly 2, so as to realize switching of a radio frequency signal path, and the transmission direction and path of the radio frequency signal can be flexibly changed according to actual requirements.

[0022] Specifically, the shielding box body 1 comprises a middle block 11, a top plate 12 and a bottom plate 13. The upper surface of the middle block 11 forms a ring-shaped shielding groove 111, and a vertical hole 112 is arranged in the middle block 11 and penetrates the upper and lower surfaces thereof. The top plate 12 is fixed to the upper surface of the middle block 11 to close the shielding groove 111 and prevent internal radio frequency signals from leaking to the outside. The bottom plate 13 is fixed to the lower surface of the middle block 11 to close the vertical holes 112 and further enhance the shielding effect. The top plate 12 and the bottom plate 13 can be fixed to the middle block 11 by welding or bolt connection and the like. For example, laser welding can be used in welding to make the connection more firm and ensure good sealing and conductivity.

[0023] Specifically, the coaxial transmission line assembly 2 can effectively reduce transmission loss and improve the quality of signal transmission. Each of the coaxial transmission line assemblies 2 is installed in a corresponding vertical hole 112, one end of each of the coaxial transmission line assemblies 2 penetrates the upper side of the shielding box body 1 to form an internal radio frequency contact 21, and the other end penetrates the lower side of the shielding box body 1 to form a bottom radio frequency port 22 for vertical connection with a user radio frequency board. The conductive part of the coaxial transmission line assembly 2 can be made of copper, because copper has good conductivity and can reduce signal attenuation in the transmission process. The insulating layer can be made of polytetrafluoroethylene or other low-loss materials to further improve the transmission performance. During installation, the coaxial transmission line assembly 2 can be inserted into the vertical hole 112 first, and then sealed with sealing glue to prevent external dust and moisture from entering and affecting the performance.

[0024] Specifically, the radio frequency reed 3 is a movable conductor and is arranged in the shielding groove 111. The radio frequency reed 3 can be made of beryllium bronze or other materials with good elasticity and strong conductivity, so as to ensure its movability and good conductivity. The radio frequency reed 3 can be designed in a sheet shape to increase the contact area with the internal radio frequency contact 21 and improve the stability of signal transmission.

[0025] Specifically, the electromagnetic driving device 4 is used to drive the at least one radio spring 3 to move. The electromagnetic driving device 4 can adopt an electromagnetic coil, which generates a magnetic field by being powered on and powered off, and attracts or releases the radio spring 3 to realize the movement thereof. When the electromagnetic coil is powered on, a magnetic field is generated to attract the radio spring 3 to move close, so as to be connected with the corresponding internal radio contact 21; when the electromagnetic coil is powered off, the magnetic field disappears, and the radio spring 3 returns to the original position under the action of its own elastic force, so as to be disconnected.

[0026] The embodiment also includes a reset mechanism 5, which includes a reverse spring 51 and a fixed medium 52. The reverse spring 51 has a fixed end 511 and a plurality of movable ends 512, and the fixed end 511 is fixed to the top plate 12. Each movable end 512 is connected with the corresponding radio spring 3 through the fixed medium 52, and is driven by the electromagnetic driving device 4. The fixed medium 52 is column-shaped, and functions to ensure the synchronous movement between the reverse spring 51 and the radio spring 3. The reverse spring 51 can be made of stainless steel or other materials with good elasticity and corrosion resistance, and the fixed medium 52 can be made of ceramic or other materials with good insulation performance.

[0027] The reverse spring 51 is provided with a first non-circular anti-rotation hole 513, the radio spring 3 is provided with a second non-circular anti-rotation hole 31, and the top plate 12 is provided with a clearance hole 121. One end of the fixed medium 52 is fixedly inserted into the first non-circular anti-rotation hole 513, and the other end is fixedly inserted into the second non-circular anti-rotation hole 31 after passing through the clearance hole 121. The design of the non-circular anti-rotation hole can prevent the fixed medium 52 from rotating, and ensure the connection stability of the reverse spring 51 and the radio spring 3. The fixed end 511 is fixed to the top plate 12 via at least one fixed block 53. The fixed block 53 can be made of aluminum alloy or other lightweight and high-strength materials, and the fixed end 511 of the reverse spring 51 is fixed to the top plate 12 by means of bolts or glue.

[0028] Each movable end 512 is formed with a force arm 5121, and the electromagnetic driving device 4 includes a plurality of electromagnetic driving members 41, each of which is used to drive the corresponding force arm 5121 to move. In this way, direct impact between the electromagnetic driving part and the radio part can be avoided, thereby improving the performance of the switch. The electromagnetic driving member 41 is an electromagnetic coil, which is fixed to the top plate 12 and located above the corresponding force arm 5121. The force arm 5121 is magnetically coupled with the electromagnetic coil, and the electromagnetic coil can be powered on or powered off to attract or release the corresponding force arm 5121.

[0029] A plurality of through holes 131 coaxially communicated with the vertical holes 112 are formed on the bottom plate 13, the lower ends of the coaxial transmission line assemblies 2 are respectively arranged to pass through the corresponding through holes 131, and the lower ends of the coaxial transmission line assemblies 2 are respectively fixed with the patches 23 arranged on the lower surface of the bottom plate 13. The patch 23 is used for facilitating the interface connection with the user radio frequency board. The patch 23 can be in the form of a solder pad, which is fixed on the lower end of the coaxial transmission line assembly 2 and the lower surface of the bottom plate 13 by welding to ensure good electrical connection.

[0030] The number of the coaxial transmission line assemblies 2 is four, and the four coaxial transmission line assemblies 2 are respectively used for connecting different channels of the user radio frequency board. In this way, the independent transmission and switching of multiple radio frequency signals can be realized, and different use requirements can be met.

[0031] The implementation principle of the embodiment is that the shielding box body 1 is designed to effectively shield external electromagnetic interference and ensure the stability of the internal radio frequency signal of the switch. The coaxial transmission line assembly 2 is used to realize the vertical interconnection with the user radio frequency board, which reduces the impedance matching problem of the high frequency band and improves the upper limit of the frequency and the upper limit of the application frequency of the switch itself, and can reach the millimeter wave frequency band. The electromagnetic driving device 4 drives the radio frequency reed 3 to move, and the reset mechanism 5 ensures the reset of the radio frequency reed 3, so that the switch can work stably and reliably. Compared with the prior art, the switch significantly improves the high-frequency performance on the basis of miniaturization, and meets the needs of modern communication and electronic equipment for high-performance microwave mechanical switches.

[0032] Embodiment 2

[0033] The difference between the embodiment and the above-mentioned embodiments is that the structure of the shielding box body can be manufactured in an integrated molding manner instead of being divided into an intermediate block, a top plate and a bottom plate. The integrated molding shielding box body can be manufactured by casting or other processes, has higher overall strength and better shielding effect. At the same time, high-precision numerical control machining technology can be used for machining the vertical holes to ensure the size accuracy and position accuracy of the vertical holes, thereby improving the installation accuracy of the coaxial transmission line assembly.

[0034] The implementation principle of the embodiment is that the integrated molding shielding box body reduces the assembly links and reduces the risk of reduced shielding performance caused by improper assembly. The high-precision vertical hole machining ensures the installation stability of the coaxial transmission line assembly, further improves the performance and reliability of the switch, and especially in a high-frequency environment, can better ensure the stable transmission of signals. Compared with the traditional assembled structure, the integrated molding shielding box body has higher consistency and durability.

[0035] Embodiment 3

[0036] The embodiment is further integrated with intelligent sensing and control unit based on the embodiment 1, so that the switch is upgraded from a passive executor to an intelligent sensing and executing node. The difference is that: Inside the shielding box 1, a microcontroller (MCU), at least one position sensor and at least one temperature sensor are also integrated.

[0037] Specifically, the position sensor (Hall sensor in this embodiment) is fixed on the top plate 12 for real-time non-contact monitoring of the accurate vertical position of the corresponding radio frequency reed 3 or force arm 5121. The temperature sensor is arranged on the middle block 11 near the internal radio frequency contact 21 to monitor the core working temperature of the switch when transmitting high-power signals in real time.

[0038] The microcontroller (MCU) is connected to the position sensor, temperature sensor and external electromagnetic drive 41 through internal circuit. It receives switch instructions from external system and forms a closed-loop control system according to sensor feedback information.

[0039] The implementation principle of the embodiment is: State sensing and closed-loop control: when the microcontroller (MCU) receives the switching instruction, it drives the electromagnetic drive 41 to work. At the same time, the position sensor feeds back the real-time displacement data of the radio frequency reed 3 to the MCU. The MCU can accurately adjust the driving current by comparing the actual position with the preset optimal contact position, so as to realize precise control of contact pressure and avoid driving overshoot or deficiency. In addition, the microcontroller (MCU) can record the number of switch actions and judge whether the contact is worn out by monitoring the long-term trend of position data, and actively compensate the driving stroke, so as to realize fault prediction and health management (PHM).

[0040] Temperature sensing and power compensation: when the switch is working, the temperature sensor monitors the contact temperature in real time. If the temperature exceeds the preset safety threshold, the MCU can perform two actions: one is to send an overheating alarm signal to the main system through a dedicated pin; the other is to fine-tune the driving parameters of the electromagnetic drive 41 according to the temperature data, so as to compensate for the change of contact pressure caused by thermal expansion and contraction of materials, thereby ensuring the working stability and power tolerance of the switch in high-power and wide-temperature environment.

[0041] By introducing intelligent sensing and control unit, the reliability, predictability and environmental adaptability of the switch are greatly improved, so that it is not only a signal switching tool, but also an intelligent component that can diagnose and adapt itself.

[0042] The above description of specific embodiments of the present application is not to be construed as the only embodiments of the present application. Various other changes and modifications can be made thereto without departing from the scope of the present application.

Claims

1. A high-performance radio frequency switch with a fully shielded coaxial structure, characterized in that: include: A shielding box (1), the shielding box (1) is made of a metal material and has a shielding slot (111) and a plurality of vertical holes (112) vertically connected to the shielding slot (111); A plurality of coaxial transmission line assemblies (2), each of the coaxial transmission line assemblies (2) being installed in the corresponding vertical hole (112), one end of which passes through the top of the shielding box (1) to form an internal radio frequency contact (21), and the other end of which passes through the bottom of the shielding box (1) to form a bottom radio frequency port (22) for vertically interconnecting with a user radio frequency board; A plurality of radio frequency reeds (3) arranged in the shielding slot (111), wherein the radio frequency reeds (3) are movable conductors; An electromagnetic drive device (4) is used to drive at least one of the radio frequency reeds (3) to move, so as to selectively connect or disconnect the internal radio frequency contacts (21) of the plurality of coaxial transmission line assemblies (2), thereby achieving switching of radio frequency signal paths.

2. The high-performance RF switch with a fully shielded coaxial structure according to claim 1, characterized in that: The shielding box (1) includes an intermediate block (11), a top plate (12) and a bottom plate (13); the upper surface of the intermediate block (11) forms the shielding groove (111); the shielding groove (111) is annular; the vertical holes (112) are opened in the intermediate block (11) and pass through the upper and lower surfaces of the intermediate block (11); the top plate (12) is fixed to the upper surface of the intermediate block (11) to close the shielding groove (111); the bottom plate (13) is fixed to the lower surface of the intermediate block (11) to close each of the vertical holes (112).

3. The high-performance RF switch with a fully shielded coaxial structure according to claim 2, characterized in that: The invention also includes a reset mechanism (5), wherein the reset mechanism (5) includes a counter-spring piece (51) and a fixed dielectric member (52), wherein the counter-spring piece (51) has a fixed end (511) and a plurality of movable ends (512), wherein the fixed end (511) is fixed to the top plate (12), and each movable end (512) is connected to the corresponding radio frequency spring piece (3) through the fixed dielectric member (52), and is driven together by the electromagnetic driving device (4).

4. The high-performance RF switch with a fully shielded coaxial structure according to claim 3, characterized in that: The anti-spring piece (51) is provided with a first non-circular anti-rotation hole (513), the radio frequency spring piece (3) is provided with a second non-circular anti-rotation hole (31), and the top plate (12) is provided with a clearance hole (121). One end of the fixed dielectric member (52) is fixedly inserted into the first non-circular anti-rotation hole (513), and the other end of the fixed dielectric member (52) passes through the clearance hole (121) and is fixedly inserted into the second non-circular anti-rotation hole (31).

5. The high-performance RF switch with a fully shielded coaxial structure according to claim 3, characterized in that: The fixed end (511) is fixed to the top plate (12) via at least one fixing block (53).

6. The high-performance RF switch with a fully shielded coaxial structure according to claim 3, characterized in that: Each movable end (512) is formed with a force-bearing arm (5121), and the electromagnetic driving device (4) includes a plurality of electromagnetic driving components (41), and each electromagnetic driving component (41) is used to drive the corresponding force-bearing arm (5121) to move.

7. The high-performance RF switch with a fully shielded coaxial structure according to claim 6, characterized in that: The electromagnetic driving component (41) is an electromagnetic coil, which is fixed to the top plate (12) and located above the corresponding force-bearing arm (5121). The force-bearing arm (5121) is magnetically coupled to the electromagnetic coil. The electromagnetic coil can be powered on or off to absorb or release the corresponding force-bearing arm (5121).

8. The high-performance RF switch with a fully shielded coaxial structure according to claim 2, characterized in that: The bottom plate (13) is provided with a plurality of through holes (131) coaxially connected to each of the vertical holes (112); the lower end of each of the coaxial transmission line components (2) passes through the corresponding through hole (131); the lower end of each of the coaxial transmission line components (2) is fixed with a patch (23); the patch (23) is arranged to be attached to the lower surface of the bottom plate (13).

9. The high-performance RF switch with a fully shielded coaxial structure according to claim 1, characterized in that: The number of the coaxial transmission line components (2) is four, and the four coaxial transmission line components are respectively used to connect different channels of the user radio frequency board.

10. The high-performance RF switch with a fully shielded coaxial structure according to claim 1, characterized in that: Also includes: a microcontroller; at least one position sensor for monitoring the position of the radio frequency reed (3); as well as at least one temperature sensor for monitoring operating temperature; The microcontroller is connected to the position sensor, the temperature sensor and the electromagnetic drive device (4) respectively, and is configured as follows: receiving a position feedback signal from the position sensor to perform closed-loop control on the electromagnetic drive device (4), thereby accurately adjusting the contact state of the radio frequency reed (3); as well as Receive the temperature feedback signal from the temperature sensor to perform a preset temperature compensation or alarm action.

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