Ship signal monitoring module structure and ship automation system

Abstract

The invention provides a ship signal monitoring module structure and a ship automation system, the ship signal monitoring module structure comprises a case, a panel assembly, a back plate and a plurality of functional modules, the structure adopts a systematic electromagnetic shielding and electrostatic discharge design, and the ship signal monitoring module structure comprises a case-level shielding system and a control system, the inner surface subjected to conductive oxidation treatment, the elastic shielding reed in contact with the mounting bracket and the independent grounding interface form a first-stage shielding and grounding path; according to the module-level shielding system, gaps between panels of all functional modules are filled with shielding materials, and the panels and the case are electrically and continuously connected through elastic shielding reeds and anti-falling screws to form second-level shielding. According to the board card level shielding system, a circuit layout and protection design including a complete ground plane, an isolation design and an electrostatic discharge strip is adopted for a PCB board card of each functional module, and third-level shielding is formed. And the case-level shielding system, the module-level shielding system and the board-card-level shielding system are connected with one another through low-impedance grounding paths to form a comprehensive protection system for cooperative work.

Description

Technical Field

[0001] This invention belongs to the technical field of ship electronic equipment structure design, and in particular relates to a ship signal monitoring module structure and ship automation system, especially a multi-layer shielding structure that can effectively suppress electromagnetic interference and provide reliable electrostatic protection. Background Technology

[0002] The presence of numerous cables, electrical equipment, and radar systems in ship engine rooms and bridges results in strong electromagnetic radiation. Signal monitoring modules commonly used on ships are susceptible to interference from this electromagnetic radiation, affecting their operational stability and signal acquisition accuracy.

[0003] Currently, to avoid the aforementioned interference, shipboard signal monitoring modules typically employ metal cabinets for electromagnetic shielding. Installing the signal monitoring modules within a metal cabinet effectively shields the equipment inside.

[0004] The disadvantages of using this type of electromagnetic shielding method are as follows: To achieve sufficient shielding, the production and processing costs of the cabinet will increase, adding extra material and coating costs and weight. At the same time, the heat dissipation and shielding effect of the cabinet are mutually restrictive; pursuing a high shielding effect will limit heat dissipation within the cabinet, thus increasing the cost of the heat dissipation solution. Furthermore, simply using the cabinet for shielding is unlikely to achieve satisfactory results.

[0005] Therefore, a systematic, multi-layered, low-impedance shielding and grounding structure design is needed to comprehensively improve the electromagnetic compatibility and anti-electrostatic discharge capability of ship signal monitoring modules. Summary of the Invention

[0006] In view of this, the purpose of this invention is to solve the problem that the current ship signal monitoring module uses a cabinet shielding method, which has high requirements for the cost and weight of the cabinet.

[0007] In a first aspect, embodiments of the present invention provide a ship signal monitoring module structure, based on a chassis, a panel assembly, a backplate, and multiple functional modules. The structure employs a systematic electromagnetic shielding and electrostatic discharge design, including:

[0008] Chassis-level shielding system: The chassis serves as the overall shielding shell, and the first level of shielding and grounding path is formed by the conductive anodized inner surface, the elastic shielding springs that contact the mounting bracket, and the independent grounding interface;

[0009] Modular shielding system: The gaps between the panels of each functional module are filled with shielding material, and the panels are electrically connected to the chassis through elastic shielding springs and anti-loosening screws, forming a second level of shielding;

[0010] Board-level shielding system: The PCB boards of each functional module adopt circuit layout and protection design including a complete ground plane, isolation design and electrostatic discharge strip, which constitutes the third level of shielding;

[0011] The chassis-level, module-level, and board-level shielding systems are interconnected through a low-impedance grounding path to form a comprehensive protection system that works in concert.

[0012] Preferably, the low-impedance grounding path includes:

[0013] Internal module path: The PCB board is connected to the plug-in panel by metal screws, and the connection points of the PCB board are copper-plated.

[0014] Module to chassis path: The plug-in panel is connected to the electrostatic discharge strip inside the chassis via elastic shielding springs and metal anti-loosening screws;

[0015] Chassis to ground path: The grounding threaded hole on the side wall of the chassis is connected to the external grounding copper busbar through the grounding wire;

[0016] Backplane grounding path: The signal ground and protective ground on the backplane module are connected through an RC network to provide a discharge path for static electricity.

[0017] Preferably, the PCB design in the board-level shielding system includes: adopting a multi-layer board structure and laying a complete ground plane; grounding the critical clock signal lines; setting independent system working ground GND, channel working ground GND_ISO and system protective ground PGND, wherein PGND is connected to the panel through panel fixing screws, and GND and PGND are connected through resistors and capacitors.

[0018] Preferably, the board-level shielding system further includes a channel isolation design, employing isolated power supplies and signal isolators to achieve electrical isolation between channels and the system, and between channels themselves.

[0019] Preferably, the chassis and main structural components are made of aluminum alloy, and all contact surfaces are treated with conductive oxidation; the shielding material filling the gaps between the panels in the module-level shielding system is stainless steel spring sheets.

[0020] Preferably, the chassis is provided with a mounting flange, which can be installed in a cabinet or wall-mounted using a wall-mounting bracket; when wall-mounted, the contact area between the chassis and the wall-mounting bracket is treated with conductive oxidation to ensure good contact.

[0021] The embodiments of the present invention bring the following beneficial effects:

[0022] This invention constructs a complete electromagnetic protection system through a three-in-one shielding and grounding design at the chassis, module, and board levels, ensuring the high reliability of the module in the complex electromagnetic environment of a ship. It is technically easy to implement, has a low cost, and provides better overall shielding.

[0023] Other features and advantages of the invention will be set forth in the following description, and some features will be obvious from the description or may be learned by practicing the invention. The objects and other advantages of the invention are realized and obtained through the structures particularly pointed out in the description, claims, and drawings.

[0024] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the module and chassis provided in an embodiment of the present invention.

[0026] Figure 2 This is a schematic diagram of the signal monitoring module provided in an embodiment of the present invention.

[0027] Figure 3 This is a schematic diagram of the chassis-level shielding and grounding path provided in an embodiment of the present invention.

[0028] Figure 4 This is a schematic diagram of the electrostatic discharge strip for the circuit board provided in an embodiment of the present invention. Detailed Implementation

[0029] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0030] This embodiment describes a signal monitoring module installed in the engine room of a ship. The chassis is made of aluminum alloy profile, and all internal surfaces and contact surfaces with the wall mount bracket are treated with conductive oxidation. During installation, the chassis is first fixed to the bulkhead using the wall mount bracket, ensuring that the contact surfaces are clean and the elastic shielding springs are under good pressure. The lead wire of the external grounding copper busbar is connected to the M6 ​​grounding threaded hole on the right side of the chassis. The PCB board is fixed to its corresponding aluminum alloy panel using copper pillars and metal screws, with a large area of ​​copper plating around the screw mounting holes on the PCB. Then, these modules are inserted into the corresponding sockets on the back panel of the chassis via the guide rails on the front side of the chassis. During insertion, the stainless steel springs on the side of the panel are in close contact with the adjacent panel, and the elastic shielding springs at the top of the panel are in contact with the upper beam of the chassis. Finally, each module panel is fastened to the chassis with metal anti-loosening screws, which also connect the module panel to the electrostatic discharge strip inside the chassis.

[0031] For details, please refer to the following structure. Figures 1-4 It mainly includes a chassis, front panel assembly, backplane (such as BM7001), and 18 functional modules. The systematic electromagnetic shielding and electrostatic discharge are divided into three levels:

[0032] 1. Chassis-level shielding system:

[0033] Overall shielding: The chassis frame is made of aluminum alloy profiles, which serve as the main shielding body, supporting, protecting and electromagnetically shielding the internal components.

[0034] Surface treatment: The fixed contact surfaces of the chassis and cabinet or wall mount bracket, as well as the inner surfaces of chassis components, are all subjected to conductive oxidation treatment to reduce contact resistance. Specifically, the surface treatment involves spraying a fine-textured black powder, Pantong Black 5C, onto the cut surfaces of openings to ensure reliable electrical connections at screws, springs, and other joints.

[0035] Flexible contact: The chassis is designed with flexible shielding springs to ensure electrical continuity with the mounting bracket.

[0036] Independent grounding: The right side of the chassis is equipped with a dedicated grounding threaded hole, which can be directly connected to the external grounding copper busbar through the grounding wire to provide a low impedance earth path.

[0037] 2. Module-level shielding system:

[0038] Panel-to-panel shielding: Stainless steel springs and other elastic shielding materials are inlaid in the side gaps between adjacent plug-in panels to increase electrical continuity between plug-in components and fill the gaps. Beryllium copper alloy elastic shielding springs are preferred as the elastic shielding material.

[0039] Panel-to-Chassis Connection: A spring-loaded retaining clip is installed at the connection point between the panel and the chassis, and secured with a metal anti-loosening screw. This screw directly connects the module to the electrostatic discharge strip inside the chassis.

[0040] Internal grounding: The metal casings of components mounted on the panel (such as buttons and indicator lights) must make reliable contact with the panel. The inner surface of the panel undergoes conductive oxidation treatment.

[0041] 3. Board-level shielding system:

[0042] PCB Design: A multi-layer board design is adopted, with a complete ground plane to facilitate the discharge of interference signals.

[0043] Optimize wiring: reduce wire discontinuities and avoid 90° bends; ground the clock signal lines; reduce loop area.

[0044] Component selection: Prioritize low-power, surface-mount packaged components with good EMC performance.

[0045] Grounding Design: System operating ground GND, digital circuit reference ground, uses multi-point grounding. Channel operating ground GND_ISO provides an independent reference ground for analog channel circuits. System protective ground PGND is used for electrostatic discharge. PGND is connected to the panel via panel mounting screws. GND and PGND are connected via a resistor and capacitor to discharge high-frequency electrostatic signals.

[0046] Isolation and Protection: The channels employ an isolation design, using isolated power supplies and signal isolators to prevent crosstalk between channels and between channels and the system. The board features an electrostatic discharge strip, providing a pre-defined discharge path for any static electricity that may be introduced into the interface. The interface circuitry incorporates dedicated EMC protection design (e.g., the addition of TVS diodes). The electrostatic discharge strip is designed to surround the board interface, connecting to the inner layer and outer shell via vias and screws. The anti-loosening screws are segmented and threadless to ensure they will not fall off due to vibration even if loosened; surrounding the board interface, they are tightly connected to the inner layer's PGND plane via multiple vias.

[0047] Synergy of the three levels of systems: The shielding systems mentioned above are interconnected through the low-impedance grounding path (inside the module -> from the module to the chassis -> from the chassis to the ground) to form a complete Faraday cage and a high-efficiency electrostatic discharge network from the chip level to the system level, thereby synergistically improving the overall EMC performance.

[0048] In this embodiment of the invention, the chassis passed the electromagnetic compatibility test of a third-party organization and meets the GD22-2015 standard.

[0049] It should be noted that, in this document, the terms “comprising,” “including,” or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0050] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A ship signal monitoring module structure, comprising a chassis, a panel assembly, a backplane, and multiple functional modules, characterized in that, The structure employs a systematic electromagnetic shielding and electrostatic discharge design, including: Chassis-level shielding system: The chassis serves as the overall shielding shell, and the first level of shielding and grounding path is formed by the conductive anodized inner surface, the elastic shielding springs that contact the mounting bracket, and the independent grounding interface; Modular shielding system: The gaps between the panels of each functional module are filled with shielding material, and the panels are electrically connected to the chassis through elastic shielding springs and anti-loosening screws, forming a second level of shielding; Board-level shielding system: The PCB boards of each functional module adopt circuit layout and protection design including a complete ground plane, isolation design and electrostatic discharge strip, which constitutes the third level of shielding; The chassis-level, module-level, and board-level shielding systems are interconnected through a low-impedance grounding path to form a comprehensive protection system that works in concert.

2. The structure of the ship signal monitoring module according to claim 1, characterized in that, The low-impedance grounding path includes: Internal module path: The PCB board is connected to the plug-in panel by metal screws, and the connection points of the PCB board are copper-plated. Module to chassis path: The plug-in panel is connected to the electrostatic discharge strip inside the chassis via elastic shielding springs and metal anti-loosening screws; Chassis to ground path: The grounding threaded hole on the side wall of the chassis is connected to the external grounding copper busbar through the grounding wire; Backplane grounding path: The signal ground and protective ground on the backplane module are connected through an RC network to provide a discharge path for static electricity.

3. The structure of the ship signal monitoring module according to claim 1, characterized in that, The PCB design of the board-level shielding system includes: It adopts a multi-layer board structure and lays a complete ground plane; Grounding is applied to critical clock signal lines; Set up independent system working ground GND, channel working ground GND_ISO and system protection ground PGND. PGND is connected to the panel via panel mounting screws, and GND and PGND are connected via resistors and capacitors.

4. The structure of the ship signal monitoring module according to claim 3, characterized in that, The board-level shielding system also includes a channel isolation design, employing isolated power supplies and signal isolators to achieve electrical isolation between channels and the system, and between channels themselves.

5. The structure of the ship signal monitoring module according to claim 1, characterized in that, The chassis and main structural components are made of aluminum alloy, and all contact surfaces are treated with conductive oxidation; the shielding material filling the gaps between the panels in the module-level shielding system is stainless steel spring sheets.

6. The structure of the ship signal monitoring module according to claim 1, characterized in that, The chassis is equipped with a mounting flange and can be installed in a cabinet or wall-mounted using a wall-mounting bracket. When wall-mounted, the contact area between the chassis and the wall-mounting bracket is treated with conductive oxidation to ensure good contact.

7. A ship automation system, characterized in that, The structure includes a ship signal monitoring module with high shielding reliability as described in any one of claims 1-6.

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