A dual-piece electronic tag for a vehicle

Abstract

This utility model discloses a dual-chip vehicle-mounted electronic tag, belonging to the technical field of vehicle-mounted electronic equipment. The tag includes an OBU (On-Board Unit) host and a detachable user card mounted on the OBU host. The user card includes a card housing, a dual-interface card unit, a display unit, and an energy storage unit. The dual-interface card unit is located inside the card housing and has both contact and contactless communication interfaces. The display unit is located on the surface or inside the card housing and can be displayed through the housing for information display. The energy storage unit is located inside the card housing and is electrically connected to the display unit. This utility model, through the built-in energy storage unit in the user card, allows the display unit to operate independently for at least 30 seconds after the user card is removed from the OBU host. Users can directly check their card balance and transaction status at manual lanes or service points without relying on host power or dedicated card reading equipment, effectively solving the problem of existing dual-chip OBU user cards being unable to independently display information after removal.

Description

Technical Field

[0001] This utility model belongs to the field of vehicle electronic equipment technology, and in particular relates to a dual-plate vehicle electronic tag. Background Technology

[0002] In the Electronic Toll Collection (ETC) system, the On-Board Unit (OBU) is the core device for vehicle identification and electronic toll deduction. The existing dual-chip OBU consists of an OBU host and a detachable user card. When the user card is inserted into the host, it supports non-stop toll collection. After being removed, it can be used in manual toll lanes to complete the card swipe deduction in a contactless manner, thus accommodating both ETC passage and manual toll collection scenarios.

[0003] However, existing dual-chip OBUs still have the following shortcomings: First, the user card does not have an independent display function. Users need to rely on the display module on the OBU host or insert the card into a dedicated reading and writing device to understand information such as the card balance and transaction status. After the card is removed, the information on the card cannot be obtained intuitively, which is inconvenient to use.

[0004] Secondly, when the ETC lane malfunctions and the user needs to switch to the manual lane, the user cannot directly view the transaction amount, balance, or other information on the card after removing the card, which affects the user experience.

[0005] Although the single-chip OBU is small in size, it does not have a physical user card and cannot be used for settlement in manual lanes, thus limiting its applicable scenarios.

[0006] Therefore, there is an urgent need to design a dual-plate vehicle-mounted electronic tag to solve the problems mentioned above. Utility Model Content

[0007] The purpose of this utility model is to provide a dual-chip vehicle-mounted electronic tag that can independently display information even after the user card is removed from the OBU host, making it convenient for users to intuitively view the card balance and transaction status without relying on the OBU host display module. This solves the problem in existing dual-chip OBUs where the user card cannot independently display information after being removed from the host, resulting in users not being able to intuitively obtain card information at manual lanes or service outlets, thus affecting the convenience of use.

[0008] To achieve the above objectives, the specific technical solution of this utility model for a dual-piece vehicle-mounted electronic tag is as follows: A dual-chip vehicle-mounted electronic tag includes an OBU (On-Board Unit) host and a detachable user card mounted on the OBU host. The user card includes: Card housing; The dual-interface card unit is located inside the card housing and has a contact communication interface and a non-contact communication interface. The display unit is located on the surface or inside the card housing and can be displayed through the card housing; it is used to display information. The energy storage unit is located inside the card housing and is electrically connected to the display unit; After the user card is installed on the OBU host, the display unit is powered by the OBU host through the contact communication interface, and the energy storage unit is charged by the OBU host through the contact communication interface. When the user card is separated from the OBU host, the energy storage unit supplies power to the display unit to maintain the information display.

[0009] Furthermore, the user card also includes a charging management circuit, which is connected in series between the contact communication interface and the energy storage unit. When the user card is connected to the OBU host, the charging management circuit controls the charging current and charging voltage of the energy storage unit and prevents the energy storage unit from supplying power to the OBU host in reverse. When the user card is separated from the OBU host, the charging management circuit cuts off the electrical connection between the energy storage unit and the contact communication interface.

[0010] Furthermore, the user card also includes a display control chip, which is electrically connected to the dual interface card unit, the energy storage unit, and the display unit, respectively. When the user card is combined with the OBU host, the dual interface card unit receives display commands and display data from the OBU host through a contact communication interface, and forwards the display commands and display data to the display control chip, which drives the display unit to display. When the user card is separated from the OBU host, the energy storage unit supplies power to the dual interface card unit, the display control chip, and the display unit. The dual interface card unit sends display data to the display control chip, which drives the display unit to display.

[0011] Furthermore, the dual-interface card unit includes a dual-interface card chip and a contact array. The dual-interface card chip and the contact array are electrically connected. The contact array is disposed on the card housing and is used to contact and cooperate with the OBU host to form a contact-type communication interface. The dual-interface card chip is electrically connected to the display control chip.

[0012] Furthermore, the dual-interface card unit also includes a high-frequency coil antenna, which is electrically connected to the contactless communication interface of the dual-interface card chip to enable contactless card reading.

[0013] Furthermore, the display unit includes an LED lamp matrix, which is electrically connected to the display control chip to illuminate and display information.

[0014] Furthermore, the OBU host includes a host housing and an ETC main control board. The ETC main control board is installed inside the host housing and is equipped with a spring pin array. The spring pin array and the contact array make contact with each other to form a contact communication interface.

[0015] Furthermore, the main unit casing is provided with an installation card slot, in which the user card can be detachably installed.

[0016] Furthermore, the OBU host and the user card are detachably fixedly connected via a magnetic structure; The main unit housing has a first connector, the position of which corresponds to the card slot. The card housing has a second connector, and the first connector and the second connector are magnetically attracted to each other so that one side of the user card is attached to the OBU main unit.

[0017] Furthermore, the OBU host and the user card are detachably fixedly connected via a snap-fit ​​structure; The side wall of the mounting slot is provided with a buckle, and the card housing is provided with a limiting component. The position of the limiting component corresponds to the position of the buckle. The buckle and the limiting component engage to fix the user card in the mounting slot.

[0018] This utility model has the following advantages: By using the built-in energy storage unit in the user card, the user card can still independently maintain the operation of the display unit for no less than 30 seconds after being removed from the OBU host. Users can directly check the card balance and transaction status at manual lanes or service outlets without relying on host power supply or dedicated card reading equipment. This effectively solves the problem that existing dual-chip OBU user cards are completely disabled and unable to display information independently after being removed. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the structure of the OBU host and user card of this utility model; Figure 2 This is a schematic diagram of the structure of the OBU host and the user card after separation. Figure 3 This is an exploded view of the user card of this utility model; Figure 4 This is an exploded view of the OBU host of this utility model; Figure 5 This is a schematic diagram of the structure of the OBU host and the user card connected by a magnetic attraction structure. Figure 6 This is a schematic diagram of the structure of the OBU host and the user card connected by a snap-fit ​​structure. Figure 7 This is a schematic diagram of the electrical control connection of the OBU host of this utility model; Figure 8 This is a schematic diagram of the electronic control connection of the user card of this utility model; The markings in the diagram are as follows: 1. OBU main unit; 11. Main unit housing; 111. Main unit lower housing; 112. Main unit upper housing; 12. Mounting card slot; 13. Spring pin hole; 14. ETC main control board; 15. Spring pin array; 16. Adhesive backing; 17. Buckle; 18. Guide post; 2. User card; 21. Card housing; 211. Card lower housing; 212. Card upper housing; 213. Light mask; 22. Card plate; 23. Display unit; 24. Limiting component; 25. Guide groove. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0021] Those skilled in the art will understand that although some embodiments herein include certain features included in other embodiments but not others, combinations of features from different embodiments are intended to be within the scope of this invention and form different embodiments. For example, in the claims, any of the claimed embodiments can be used in any combination.

[0022] The following is a reference to the appendix. Figure 1 To be continued Figure 8 This invention describes a dual-plate vehicle-mounted electronic tag.

[0023] A dual-plate vehicle-mounted electronic tag includes an OBU host 1 and a detachable user card 2 mounted on the OBU host 1.

[0024] User card 2 includes card housing 21 and card plate 22, with card plate 22 installed inside card housing 21.

[0025] The card housing 21 includes an upper card housing 212, a display film, a light mask 213, and a lower card housing 211. The middle area of ​​the upper card housing 212 is semi-transparent, allowing the display light of the display unit 23 to pass through. The upper card housing 212 is provided with support columns for the installation and positioning of the display film, the light mask 213, and the card plate 22. The display film is a PC structure display template, with a display pattern area and a non-display pattern area. The display pattern area is transparent, and the non-display pattern area is black and opaque. The light mask 213 is a non-transparent hollow structure, with hollowed-out positions corresponding to the transparent areas of the display film, used to prevent the display light of the display unit 23 from scattering. The lower card housing 211 and the upper card housing 212 are mated together and ultrasonically welded into one piece, providing good protection. In other embodiments of this utility model, the lower card housing 211 and the upper card housing 212 can also be connected into one piece in other ways. The connection method between the lower card housing 211 and the upper card housing 212 is not limited here.

[0026] The card plate 22 is fixed in its relative position by the support column. After the card body 21 is fused together, the position of the card plate 22 is also fixed.

[0027] User card 2 also includes a dual interface card unit, a display unit 23, and an energy storage unit.

[0028] The dual-interface card unit is located inside the card housing 21 and has a contact communication interface and a non-contact communication interface.

[0029] The contact communication interface conforms to the ISO / IEC 7816 standard, and the contactless communication interface conforms to the ISO / IEC 14443 standard.

[0030] The dual-interface card unit is set on the card plate 22.

[0031] The dual-interface card unit includes a dual-interface card chip, a contact array, and a high-frequency coil antenna. The dual-interface card chip, contact array, and high-frequency coil antenna are all located on the card plate 22. The dual-interface card chip and the contact array are electrically connected. The contact array is located on the card housing 21 and is used to contact and cooperate with the OBU host 1 to form a contact communication interface. The dual-interface card chip is electrically connected to the display control chip. The high-frequency coil antenna is electrically connected to the contactless communication interface of the dual-interface card chip to realize contactless card reading.

[0032] The display unit 23 is disposed on the surface or inside the card housing 21 and can be displayed through the card housing 21 for displaying information; specifically, the display unit 23 includes an LED lamp bead matrix, which is electrically connected to the display control chip for illuminating and displaying information.

[0033] The energy storage unit is located inside the card housing 21 and is electrically connected to the display unit 23. Specifically, the energy storage unit is located on the card plate 22. The energy storage unit can be a supercapacitor, a rechargeable thin-film battery, a rechargeable solid-state micro battery, a lithium-ion capacitor, etc., as long as the energy storage unit can be accommodated inside the card housing 21.

[0034] The energy storage unit is preferably a supercapacitor with a thickness not exceeding 0.5 mm.

[0035] When user card 2 is installed on OBU host 1, display unit 23 is powered by OBU host 1 through contact communication interface, and energy storage unit is charged by OBU host 1 through contact communication interface; when user card 2 is separated from OBU host 1, energy storage unit powers display unit 23 to maintain information display on display unit 23.

[0036] User card 2 also includes a charging management circuit, which is connected in series between the contact communication interface and the energy storage unit. When user card 2 is connected to OBU host 1, the charging management circuit controls the charging current and charging voltage of the energy storage unit and prevents the energy storage unit from supplying power to OBU host 1 in reverse. When user card 2 is separated from OBU host 1, the charging management circuit cuts off the electrical connection between the energy storage unit and the contact communication interface.

[0037] User card 2 also includes a display control chip, which is electrically connected to the dual interface card unit, the energy storage unit, and the display unit. When user card 2 is combined with OBU host 1, the dual interface card unit receives display commands and display data from OBU host through a contact communication interface and forwards the display commands and display data to the display control chip, which drives the display unit to display. When user card 2 is separated from OBU host 1, the energy storage unit supplies power to the dual interface card unit, the display control chip, and the display unit. The dual interface card unit sends display data to the display control chip, which drives the display unit to display. Specifically, the display control chip is located on card board 22.

[0038] The OBU host 1 includes a host housing 11 and an ETC main control board 14, with the ETC main control board 14 installed inside the host housing 11.

[0039] The main unit housing 11 includes a lower main unit housing 111 and an upper main unit housing 112. The upper main unit housing 112 and the lower main unit housing 111 are joined together to form the main unit housing 11. The ETC main control board 14 is fixed to the lower main unit housing 111 by the buckle 17 structure on the lower main unit housing 111 without the need for screws.

[0040] A solar charging panel is installed on the lower housing 111 of the main unit. The solar charging panel is fixed to the lower housing 111 of the main unit by glue or heat fusion. A speaker is also installed on the lower housing 111 of the main unit. The speaker is fixed to the lower housing 111 of the main unit by glue. The bottom of the lower housing 111 of the main unit is provided with adhesive backing 16 and anti-tampering post holes. Adhesive backing 16 is used to install the OBU main unit 1 on the surface of objects such as the windshield of a vehicle. Anti-tampering post holes are used for the anti-tampering switch handle on the ETC main control board 14 to extend. The handle is surrounded by adhesive backing 16. After the device is activated, the anti-tampering switch is in the pressed state. After the device is removed from the mounting surface, the anti-tampering switch pops open and the device enters the disabled state.

[0041] The main unit housing 11 is also equipped with a button switch, a slide switch and a USB port. The button switch is used to control the Bluetooth function to be turned on or off; the slide switch is used to control the ETC function to be turned on or off; and the USB port is used for communication and charging.

[0042] The main unit housing 112 is equipped with a status indicator lens. The status lights on the ETC main control board 14 display the device status to the user through the lens, including low battery status, charging status, fully charged status, transaction status, Bluetooth status, etc.

[0043] The ETC main control board 14 is equipped with a spring pin array 15, which contacts and engages with the contact array to form a contact communication interface.

[0044] like Figure 7 As shown, the ETC main control board 14 integrates an MCU & BT SOC, an ESAM encryption chip, and a DSRC chip, which together constitute the electronic control core of the OBU host 1. The MCU & BT SOC is a system-on-a-chip that integrates microcontroller (MCU) and Bluetooth (BT) communication functions. It is responsible for running the control program of the OBU host 1, centrally handling functions such as transaction control, communication scheduling, status detection, and Bluetooth connection. The ESAM encryption chip is an embedded security control module used to securely store keys and account information, and to perform encryption and decryption operations on sensitive transaction data to ensure transaction security. The DSRC chip is a dedicated short-range communication chip operating in the 5.8GHz frequency band, used to establish a dedicated short-range communication link between the ETC lane and the roadside unit, enabling vehicle identification and non-stop toll collection transactions.

[0045] The main unit housing 11 is provided with an installation slot 12, and the user card 2 is detachably installed in the installation slot 12. Specifically, the installation slot 12 is provided on the main unit housing 112, and the bottom of the installation slot 12 is provided with a spring pin hole 13. The spring pin array 15 on the ETC main control board 14 protrudes through the spring pin hole 13 and is slightly higher than the bottom of the installation slot 12.

[0046] When user card 2 is installed in the card slot 12 of OBU host 1, the pin array 15 on ETC main control board 14 and the contact array on card plate 22 make contact and cooperate to form a contact communication interface. At this time, the dual interface card chip receives transaction instructions, updated balance and / or transaction amount and other display data from OBU host 1 through the contact array, and forwards the display instructions and display data to the display control chip. The display control chip drives the display unit 23 to display so that the user can view it. At the same time, OBU host 1 charges the energy storage unit through the contact array.

[0047] When user card 2 is removed from OBU host 1, the energy storage unit automatically switches to discharge state to supply power to the dual interface card chip, display control chip and display unit 23. The dual interface card chip sends display data (including card balance, transaction amount, etc.) to the display control chip, which drives the display unit to continue displaying, so that user card 2 can continue to view the latest card information after being removed from OBU host 1. Since the dual interface card unit has extremely low power consumption, the energy storage unit can maintain the operation of the dual interface card unit, display control chip and display unit 23 for no less than 30 seconds.

[0048] After the user card 2 is disconnected from the OBU host 1, its high-frequency coil antenna can be used to communicate with the 13.56MHz or NFC reader / writer at the service outlet for contactless communication, enabling operations such as recharging and querying transaction records.

[0049] In this embodiment, the user card 2 uses a dual-interface card chip as the data core. When connected, the dual-interface card chip receives transaction data and display data from the OBU host 1 through a contact array. On the one hand, it updates the account information stored in its own memory, and on the other hand, it forwards the data to be displayed to the display control chip, which drives the display unit to display the data. When disconnected, the dual-interface card chip remains in working condition, powered by the energy storage unit. The dual-interface card chip continuously sends the latest display data to the display control chip, ensuring that the display unit always displays the real-time information stored in the card.

[0050] Compared with the prior art, this utility model, through the built-in energy storage unit of the user card 2, enables the user card 2 to independently maintain the operation of the display unit 23 for no less than 30 seconds after being removed from the OBU host 1. Users can directly check the card balance and transaction status at manual lanes or service outlets without relying on host power supply or dedicated card reading equipment. This effectively solves the problem that the existing dual-chip OBU user card 2 is completely disabled and unable to display information independently after being removed.

[0051] In the first embodiment of the connection method between the OBU host 1 and the user card 2, the OBU host 1 and the user card 2 are fixedly connected in a separable manner through a magnetic attraction structure; A first connector is provided inside the main unit housing 11, and the position of the first connector corresponds to the mounting slot 12. A second connector is provided inside the card housing 21. The first connector and the second connector are magnetically attracted to each other so that one side of the user card 2 is abutted and attracted to the OBU main unit 1. Specifically, one of the first connector and the second connector is a magnet, and the other is a ferromagnetic metal.

[0052] Preferably, the upper third of the lower casing 211 of the user card 2 is angled at 5 degrees. When removing it, press the upper part of the user card 2 with a little force, and use the angled structure at the bottom of the user card 2 to make the magnetic part pop up and detach.

[0053] In a second embodiment of the connection method between the OBU host 1 and the user card 2, the OBU host 1 and the user card 2 are fixedly connected in a separable manner through a snap-fit ​​structure. The side wall of the mounting slot 12 is provided with a buckle 17, and the card housing 21 is provided with a limiting member 24. The position of the limiting member 24 corresponds to the position of the buckle 17. The buckle 17 and the limiting member 24 engage to fix the user card 2 in the mounting slot 12.

[0054] Preferably, the side wall of the mounting slot 12 is provided with a guide post 18, and the card housing 21 is provided with a guide groove 25. The position of the guide post 18 corresponds to the position of the guide groove 25. The guide post 18 can slide and be inserted along the guide groove 25. Through the cooperation of the guide post 18 and the guide groove 25, the user card 2 is guided to be inserted into the mounting slot 12 in a predetermined direction, so as to achieve precise positioning between the user card 2 and the host housing 11, while preventing the user card 2 from being inserted backwards or tilted.

[0055] During installation, the user holds the user card 2, aligns the guide groove 25 with the guide post 18, and smoothly pushes the user card 2 into the mounting slot 12 along the direction of the guide post 18. The guide post 18 slides along the guide groove 25 to the bottom, achieving initial positioning of the user card 2 and the host. During continued pushing, the snap-on 17, utilizing its elastic deformation, slides past the limiting member 24 and springs back to its original position, engaging with the limiting member 24 to achieve a secure connection between the user card 2 and the host housing 11. At this time, the spring pin array 15 on the ETC main control board 14 and the contact array on the user card 2 are accurately aligned and make contact, forming a stable contact communication interface. To remove, the user card 2 can be removed by applying slight force using the auxiliary handle on the host housing 112, allowing the snap-on 17 to disengage from the limiting member 24.

[0056] When a vehicle enters the ETC lane, user card 2 and OBU host 1 are connected. The roadside unit continuously sends inquiry signals, and the DSRC communication module in OBU host 1 is activated and establishes a link with the roadside unit. OBU host 1 requests data from the dual-interface card unit in user card 2 through the contact interaction between the pin array 15 and the contact array. After the dual-interface card unit completes security authentication, it returns the encrypted account information to OBU host 1 through the contact communication interface. OBU host 1 then forwards the information to the roadside unit, which uploads the data to the backend system to complete authentication and deduction. After successful deduction, an instruction is issued, and the vehicle passes through.

[0057] When a user needs to recharge user card 2 or check transaction records at a service point, they can directly remove user card 2 from OBU host 1. After user card 2 is removed from OBU host 1, the energy storage unit automatically supplies power to the dual interface card chip, display control chip, and display unit 23, displaying the card balance or transaction status information for the user's convenience. Subsequently, the user takes user card 2 to the 13.56MHz or NFC reader / writer at the service point and performs contactless reading and writing operations through the high-frequency coil antenna. After the operation is completed, the user brings user card 2 close to OBU host 1, and is guided to reset and reconnect through magnetic attraction or buckle 17, and the system can be put back into use.

[0058] Obviously, the above embodiments of this utility model are merely examples for clearly illustrating the present utility model, and are not intended to limit the implementation of the present utility model. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this utility model should be included within the protection scope of the claims of this utility model.

Claims

1. A dual-plate vehicle-mounted electronic tag, comprising an OBU host and a detachable user card mounted on the OBU host, characterized in that, User cards include: Card housing; The dual-interface card unit is located inside the card housing and has a contact communication interface and a non-contact communication interface. The display unit is located on the surface or inside the card housing and can be displayed through the card housing; it is used to display information. The energy storage unit is located inside the card housing and is electrically connected to the display unit; After the user card is installed on the OBU host, the display unit is powered by the OBU host through the contact communication interface, and the energy storage unit is charged by the OBU host through the contact communication interface. When the user card is separated from the OBU host, the energy storage unit supplies power to the display unit to maintain the information display.

2. The dual-piece vehicle-mounted electronic tag according to claim 1, characterized in that, The user card also includes a charging management circuit, which is connected in series between the contact communication interface and the energy storage unit. When the user card is connected to the OBU host, the charging management circuit controls the charging current and charging voltage of the energy storage unit and prevents the energy storage unit from supplying power to the OBU host in reverse. When the user card is separated from the OBU host, the charging management circuit cuts off the electrical connection between the energy storage unit and the contact communication interface.

3. The dual-piece vehicle-mounted electronic tag according to claim 1, characterized in that, The user card also includes a display control chip, which is electrically connected to the dual interface card unit, the energy storage unit, and the display unit. When the user card is connected to the OBU host, the dual interface card unit receives display commands and display data from the OBU host through a contact communication interface, and forwards the display commands and display data to the display control chip, which drives the display unit to display. When the user card is disconnected from the OBU host, the energy storage unit supplies power to the dual interface card unit, the display control chip, and the display unit. The dual interface card unit sends display data to the display control chip, which drives the display unit to display.

4. The dual-piece vehicle-mounted electronic tag according to claim 3, characterized in that, The dual-interface card unit includes a dual-interface card chip and a contact array. The dual-interface card chip and the contact array are electrically connected. The contact array is set on the card housing and is used to contact and cooperate with the OBU host to form a contact-type communication interface. The dual-interface card chip is electrically connected to the display control chip.

5. The dual-piece vehicle-mounted electronic tag according to claim 4, characterized in that, The dual-interface card unit also includes a high-frequency coil antenna, which is electrically connected to the contactless communication interface of the dual-interface card chip to enable contactless card reading.

6. The dual-piece vehicle-mounted electronic tag according to claim 3, characterized in that, The display unit includes an LED matrix, which is electrically connected to a display control chip to illuminate and display information.

7. The dual-piece vehicle-mounted electronic tag according to claim 4, characterized in that, The OBU host includes a host housing and an ETC main control board. The ETC main control board is installed inside the host housing and has a spring pin array. The spring pin array and the contact array make contact with each other to form a contact communication interface.

8. The dual-piece vehicle-mounted electronic tag according to claim 7, characterized in that, The main unit casing has an installation card slot, in which the user card can be detachably installed.

9. The dual-piece vehicle-mounted electronic tag according to claim 8, characterized in that, The OBU host and the user card are connected by a detachable magnetic structure. The main unit housing has a first connector, the position of which corresponds to the card slot. The card housing has a second connector, and the first connector and the second connector are magnetically attracted to each other so that one side of the user card is attached to the OBU main unit.

10. The dual-piece vehicle-mounted electronic tag according to claim 8, characterized in that, The OBU host and the user card are fixedly connected by a snap-fit ​​structure that allows for separation. The side wall of the mounting slot is provided with a buckle, and the card housing is provided with a limiting component. The position of the limiting component corresponds to the position of the buckle. The buckle and the limiting component engage to fix the user card in the mounting slot.

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