Anti-creeping multilayer printed circuit board structure for electric cooker

Abstract

The utility model discloses an anti-creeping multilayer printed circuit board structure for an electric cooker, which comprises a sealing layer, insulating layers and a wiring layer, the insulating layers are arranged in the sealing layer, a first conducting layer is arranged below the first group of insulating layers on the upper side in the sealing layer, a voltage sensor is arranged on one side of the first conducting layer, and a second conducting layer is arranged on the other side of the first conducting layer. One side of the voltage sensor is connected with an interface, the lower part of the first conductive layer is connected with a wiring layer through a pipeline, the bottom of the wiring layer is provided with a heat dissipation copper pipe, the lower part of the wiring layer is connected with a second conductive layer through a pipeline, one side of the second conductive layer is connected with a plurality of groups of grounding piles, and the grounding piles are connected with a power supply. The multiple groups of grounding piles are uniformly arranged along the horizontal direction of the second conductive layer, the waterproof material is adopted to seal the edge, so that the moisture resistance of the circuit board is improved, the voltage sensor is arranged on the conductive layer connected with the electric cooker to prevent the circuit board from being damaged by electric leakage, and the use safety is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of circuit board structures, in particular to a leakage-proof multilayer printed circuit board structure for an electric rice cooker. Background Art

[0002] As a common household appliance, the safety of rice cookers has received widespread attention. When designing existing printed circuit boards for rice cookers, the performance and integration of the circuit are often emphasized, but the risk of leakage in a humid environment or under insulation aging conditions may be ignored. Therefore, a structural design is needed that can not only ensure the performance of the circuit, but also effectively prevent leakage and improve the safety of the product.

[0003] According to the patent number CN108925033A, a leakage-proof circuit board for small household appliances includes a protective shell, a cover body and a circuit board body, both sides of the interior of the protective shell are threadedly installed with movable splints through adjusting bolts, the inner side of the protective shell between the movable splints is installed with a circuit board body, the surface of the circuit board body is provided with evenly distributed through holes, the interior of the through holes is provided with internal threads, a plastic column is movably installed inside the through holes, and the surface of the plastic column is provided with external threads, an adjustment knob is installed at one end of the plastic column, and a twisting groove is provided inside the adjustment knob, and the surfaces of both sides of the circuit board body are installed with fixed seats, and the fixed seats are respectively provided with slots and pins. This patent provides a series of structures to make the circuit board have the advantages of high protection, high safety and more convenient installation and disassembly during use.

[0004] However, the above design has insufficient anti-leakage performance in a humid environment where the electric cooker works during use, lacks the functions of preventing water ingress and detecting abnormal leakage and power-off, which reduces the safety of the circuit board. Therefore, in view of this, research and improvement are conducted on the existing structure and defects, and a leakage-proof multilayer printed circuit board structure for an electric cooker is proposed to achieve a more practical purpose. Utility Model Content

[0005] The utility model aims to provide a leakage-proof multilayer printed circuit board structure for an electric rice cooker, so as to solve the problem that the leakage-proof performance of the above-mentioned circuit board proposed in the background technology is insufficient during use, and the function of preventing water ingress and detecting abnormal leakage and power-off is lacking, so that the safety of the circuit board is reduced.

[0006] To achieve the above-mentioned purpose, the utility model provides the following technical scheme: a leakage-proof multilayer printed circuit board structure for an electric rice cooker, comprising a sealing layer, an insulating layer and a routing layer, characterized in that: an insulating layer is arranged inside the sealing layer, the insulating layer is arranged in four groups, and the four groups of insulating layers are evenly arranged along the vertical direction inside the sealing layer, a No. 1 conductive layer is arranged below the first group of insulating layers on the upper side of the inner part of the sealing layer, a voltage sensor is arranged on one side of the No. 1 conductive layer, an interface is connected to the wiring layer below the No. 1 conductive layer through a pipeline, a heat dissipation copper tube is arranged at the bottom of the routing layer, a No. 2 conductive layer is connected to one side of the No. 2 conductive layer through a pipeline, a grounding pile is connected to one side of the No. 2 conductive layer, a plurality of groups of grounding piles are arranged, and the plurality of groups of grounding piles are evenly arranged along the horizontal direction of the No. 2 conductive layer.

[0007] Furthermore, a group of the insulating layers are disposed above and below the routing layer, and the routing layer is separated from the first conductive layer and the second conductive layer by the insulating layers.

[0008] Furthermore, a group of the insulating layers is arranged below the second conductive layer, and a plurality of groups of holes are opened on the surface of the insulating layers so that the grounding piles are in contact with the ground through the holes.

[0009] Furthermore, the sealing layer is made of silicone resin material, the sealing layer is in the form of a rectangular frame, and the thickness of the sealing layer increases at the four corners.

[0010] Furthermore, the outer surfaces of the first conductive layer and the second conductive layer are provided with conductive wires by etching process, and the width of the conductive wires is 1.0-1.5 mm.

[0011] Furthermore, the heat dissipation copper tube is arranged at the bottom of the wiring layer in a serpentine layout, and the wall thickness of the heat dissipation copper tube is 0.5-1.0 mm.

[0012] Compared with the prior art, the utility model has the following beneficial effects: the electric cooker uses a leakage-proof multilayer printed circuit board structure, adopts a waterproof material to seal the edge to improve the moisture resistance of the circuit board, and is provided with a voltage sensor on the conductive layer connected to the electric cooker to prevent leakage from damaging the circuit board, thereby improving the safety of use. The specific contents are as follows:

[0013] The edges of the circuit board are sealed with sealants, such as silicone-based compounds, to prevent moisture and pollution from invading the board and reduce the risk of leakage and corrosion. The four corners of the sealing layer are thickened to create corner guards to reduce damage caused by mechanical impact and prevent cracks that may cause leakage. Multiple insulating layers are introduced between the conductive layers to increase the overall insulation performance of the circuit board. The insulating layer uses high dielectric strength materials, such as polyimide, which can withstand higher voltages without breakdown. At the same time, adding an insulating layer on one side of the top and bottom conductive layers can enhance the circuit board. The overall insulation performance prevents electrical short circuits and improves reliability. The wire width etched on the surface of the conductive layer is optimized to be 1.0-1.5mm. This width can ensure that the wire will not generate too much heat due to excessive resistance during long-term operation. At the same time, there is enough safety margin to handle possible current peaks, thereby reducing the heat generated by excessive resistance and reducing the risk of leakage. The two sides of the routing layer are separated from the conductive layer by an insulating layer. At the same time, a heat dissipation copper tube is arranged in a serpentine layout at the bottom of the routing layer to avoid the hot spot area causing degradation of the insulation material and indirectly causing leakage. The wall thickness of the copper tube can be between 0.5 and 1.0 mm. Such a thickness not only ensures good mechanical strength and avoids the problem of easy damage due to being too thin, but also maintains sufficient heat conduction efficiency. The serpentine layout can increase the coverage area of ​​the copper tube on the circuit board and accelerate the diffusion of heat through a larger surface area, which helps to disperse the heat more evenly, reduce the hot spot temperature, and prevent the occurrence of leakage caused by thermal changes in internal parts through heat dissipation. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is a schematic diagram of the main structure of a multi-layer printed circuit board structure for preventing leakage of electricity for an electric rice cooker according to the utility model;

[0015] Figure 2 This is a three-dimensional structural schematic diagram of a leakage-proof multilayer printed circuit board for an electric rice cooker according to the utility model;

[0016] Figure 3 The utility model is a schematic diagram of the bottom structure of a leakage-proof multilayer printed circuit board structure for an electric rice cooker.

[0017] In the figure: 1. Sealing layer; 2. Insulation layer; 3. Conductive layer No. 1; 4. Voltage sensor; 5. Interface; 6. Routing layer; 7. Heat dissipation copper tube; 8. Conductive layer No. 2; 9. Grounding pile; 10. Wire. DETAILED DESCRIPTION

[0018] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0019] See also Figure 1 - Figure 3The utility model provides a technical solution: a multi-layer printed circuit board structure for preventing leakage of electric rice cookers, including a sealing layer 1, an insulating layer 2 and a routing layer 6. The insulating layer 2 is arranged inside the sealing layer 1. The sealing layer 1 is made of silicone resin material. Silicone resin is selected as the sealing material because of its excellent temperature resistance, weather resistance and electrical insulation. The minimum and maximum thicknesses of the sealing layer are determined according to the environment in which the circuit board is expected to be used and the IP protection grade requirements. The common thickness range is between 0.5mm and 2mm. The sealing layer 1 is a rectangular frame, and the thickness at the four corners of the sealing layer 1 increases to form edge guards to reduce damage caused by mechanical impact and prevent cracks that may cause leakage. The insulating layer 2 is arranged in four groups, and the four groups of insulating layers 2 are evenly arranged in the vertical direction inside the sealing layer 1. The insulating layer is made of high dielectric strength materials, such as a specific grade of FR4 or polyimide. These materials can withstand higher voltages without breakdown, so that the circuit board maintains excellent anti-leakage performance. The upper side of the inner part of the sealing layer 1 is A first conductive layer 3 is arranged below a group of insulating layers 2, a voltage sensor 4 is arranged on one side of the first conductive layer 3, and the model of the voltage sensor 4 is LV25-P. The state of the circuit is monitored in real time by the voltage sensor 4. Once an abnormality is detected, the power supply is immediately cut off or other protective measures are taken. An interface 5 is connected to one side of the voltage sensor 4, and the circuit board can be connected to the rice cooker through the interface. A wiring layer 6 is connected below the first conductive layer 3 through a pipeline, and a group of insulating layers 2 are arranged above and below the wiring layer 6 to increase the insulation performance of the wiring layer 6 and prevent the occurrence of leakage from causing damage to the wiring layer 6. The insulation layer 2 separates the wiring layer 6 from the first conductive layer 3 and the second conductive layer 8. A heat dissipation copper tube 7 is provided at the bottom of the wiring layer 6. The heat dissipation copper tube 7 is made of copper material. The heat dissipation copper tube 7 is arranged at the bottom of the wiring layer 6 in a serpentine layout. The wall thickness of the heat dissipation copper tube 7 is 0.5-1.0 mm. Such a thickness not only ensures good mechanical strength and avoids the problem of easy damage due to being too thin, but also maintains sufficient heat conduction efficiency. The serpentine tube layout can increase the coverage area of ​​the heat dissipation copper tube 7 on the wiring layer 6, and accelerate the heat dissipation through a larger surface area. The amount of diffusion is helpful to disperse the heat more evenly, reduce the hot spot temperature, and avoid the influence of the internal temperature rise caused by the sealing effect of the sealing layer 1 on the use of the circuit board. The second conductive layer 8 is connected to the bottom of the wiring layer 6 through a pipeline. The outer surfaces of the first conductive layer 3 and the second conductive layer 8 are provided with wires 10 by etching process. The width of the wire 10 is 1.0-1.5mm. The wider the wire 10, the greater the current it can carry, because the wider wire 10 can provide a larger conductive cross-sectional area, thereby reducing the resistance and reducing the heat generated by the resistance. 1.0-1.The width of 5mm can ensure that the conductor 10 will not generate excessive heat due to excessive resistance during long-term operation, and at the same time, there is enough safety margin to handle possible current peaks. A grounding stake 9 is connected to one side of the second conductive layer 8. There are several groups of grounding stakes 9, and several groups of grounding stakes 9 are evenly arranged along the horizontal direction of the second conductive layer 8. Each group of grounding stakes 9 bears a part of the current load, thereby reducing the current density and voltage drop at a single point. This method of dispersing the burden helps to distribute the current more evenly and reduce the risk of leakage due to excessive local voltage. A group of insulating layers 2 is arranged below the second conductive layer 8. The surface of the insulating layer 2 is provided with several groups of holes, so that the grounding stakes 9 are in contact with the ground through the holes. .

[0020] Working principle: When using a multi-layer printed circuit board structure for preventing leakage of electricity for electric rice cookers, it is necessary to inspect the circuit board to check whether its various components are intact before use. Check the sealing performance of the sealing layer 1 to prevent moisture and pollution from invading the board and reduce the risk of leakage and corrosion. The edge guards set at the four corners of the sealing layer 1 are higher than the insulating layer 2 on the top of the circuit board to reduce damage caused by mechanical impact and prevent cracks that may cause leakage. After the interface 5 is connected to the electric rice cooker, the voltage sensor 4 starts working at the same time to monitor the status of the circuit in real time. Once an abnormality is detected, the power supply is immediately cut off or measures are taken. Other protective measures: insulating layers 2 are provided above and below the wiring layer 6 of the multi-layer circuit board. The integrity of the insulating layer 2 is checked. The design of the double-layer insulating layer 2 ensures the safety of the wiring layer 6. A heat dissipation copper tube 7 is provided at the bottom of the wiring layer 6. The heat dissipation copper tube 7 is arranged at the bottom of the wiring layer 6 in a serpentine layout. The wall thickness of the heat dissipation copper tube 7 is 0.5-1.0 mm. Such a thickness not only ensures good mechanical strength and avoids the problem of easy damage due to being too thin, but also maintains sufficient heat conduction efficiency. The serpentine tube layout can increase the coverage area of ​​the heat dissipation copper tube 7 on the wiring layer 6, through a larger The surface area is used to accelerate the diffusion of heat, which helps to disperse the heat more evenly, reduce the hot spot temperature, and avoid the influence of the internal temperature rise caused by the sealing effect of the sealing layer 1 on the use of the circuit board. There are wire layers above and below the routing layer 6. The No. 1 conductive layer 3 is directly connected to the rice cooker. The No. 2 conductive layer 8 is located at the bottom of the circuit board. Several groups of grounding stakes 9 are arranged evenly along the horizontal direction of the No. 2 conductive layer 8. Each group of grounding stakes 9 bears a part of the current load, thereby reducing the current density and voltage drop at a single point. This method of dispersing the burden helps to distribute the load more evenly. To distribute current and reduce the risk of leakage due to excessive local voltage, the surface of the conductive layer is provided with a wire 10 by etching. The width of the wire 10 is 1.0-1.5mm. The wider the wire 10, the greater the current it can carry, because the wider wire 10 can provide a larger conductive cross-sectional area, thereby reducing resistance and reducing the heat caused by resistance. A width of 1.0-1.5mm can ensure that the wire 10 will not generate excessive heat due to excessive resistance during long-term operation, and at the same time, there is enough safety margin to handle possible current peaks, thereby enhancing the anti-leakage performance of the circuit board.

Claims

1. A leakage-proof multilayer printed circuit board structure for an electric rice cooker, comprising a sealing layer (1), an insulating layer (2) and a wiring layer (6), characterized in that: An insulating layer (2) is arranged inside the sealing layer (1), and the insulating layer (2) is provided in four groups, and the four groups of insulating layers (2) are evenly arranged along the vertical direction inside the sealing layer (1); a first conductive layer (3) is arranged below the first group of insulating layers (2) on the upper side of the sealing layer (1); a voltage sensor (4) is arranged on one side of the first conductive layer (3); an interface (5) is connected to one side of the voltage sensor (4); a routing layer (6) is connected to the bottom of the first conductive layer (3) through a pipeline; a heat dissipation copper tube (7) is arranged at the bottom of the routing layer (6); a second conductive layer (8) is connected to the bottom of the routing layer (6) through a pipeline; a grounding pile (9) is connected to one side of the second conductive layer (8); a plurality of groups of grounding piles (9) are provided, and the plurality of groups of grounding piles (9) are evenly arranged along the horizontal direction of the second conductive layer (8).

2. The anti-leakage multilayer printed circuit board structure for an electric rice cooker according to claim 1, characterized in that: A group of insulating layers (2) are provided above and below the wiring layer (6), and the wiring layer (6) is separated from the first conductive layer (3) and the second conductive layer (8) by the insulating layers (2).

3. The anti-leakage multilayer printed circuit board structure for an electric rice cooker according to claim 1, characterized in that: A group of insulating layers (2) is arranged below the second conductive layer (8), and a plurality of groups of holes are opened on the surface of the insulating layer (2), so that the grounding piles (9) can contact the ground through the holes.

4. The anti-leakage multilayer printed circuit board structure for an electric rice cooker according to claim 1, characterized in that: The sealing layer (1) is made of silicone resin material, and is in the form of a rectangular frame, with the thickness of the four corners of the sealing layer (1) increasing.

5. The anti-leakage multilayer printed circuit board structure for an electric rice cooker according to claim 1, characterized in that: The outer surfaces of the first conductive layer (3) and the second conductive layer (8) are both provided with conductive wires (10) by means of an etching process, and the width of the conductive wires (10) is 1.0-1.5 mm.

6. The leakage-proof multilayer printed circuit board structure for an electric rice cooker according to claim 1, characterized in that: The heat dissipation copper tube (7) is arranged at the bottom of the wiring layer (6) in a serpentine layout, and the wall thickness of the heat dissipation copper tube (7) is 0.5-1.0 mm.

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