Photovoltaic junction box

Abstract

The utility model discloses a photovoltaic junction box, including box body, the box cover is rotatably connected on box body, be equipped with main control circuit board in the box body, is equipped with core chip on main control circuit board, be equipped with a plurality of positioning post in the box body, be equipped with a plurality of first locating hole on main control circuit board, be equipped with first heat dissipation board above main control circuit board, another side linear distribution of first heat dissipation board has a plurality of radiating fins, the inner wall both sides of box body are equipped with mounting block respectively, is equipped with movable slot on mounting block, movable slot is slidably connected with triangular clamping block, and spring is equipped between triangular clamping block and the inner wall of movable slot, be equipped with a plurality of heat dissipation holes on box cover, the rear end side portion of box body is equipped with a plurality of communication interface, the right side portion of box body is equipped with power interface, the utility model installs internal component convenient and fast, and the heat dissipation performance is good, makes the component can efficient operation.

Description

Technical Field

[0001] This utility model relates to a junction box, specifically a photovoltaic junction box, and belongs to the field of junction box technology. Background Technology

[0002] A photovoltaic (PV) junction box is a core component of a PV module, acting as a "bridge" connecting the PV cell strings to external circuits. Its core function is to collect the direct current generated by the PV module, concentrating the current from multiple cells and outputting it through cables, while simultaneously establishing the electrical connection between the module and equipment such as inverters. For example, Chinese utility model patent CN206226373U discloses a junction box housing for solar PV modules, specifically including a junction box body with a groove at one end; a junction box cover with an elastic snap-fit ​​at one end and a concave buckle at the opposite end; wherein the elastic snap-fit ​​can elastically press against the groove, and the junction box cover is detachably connected to the junction box body. This type of junction box often uses screws to fix internal components, which is time-consuming to assemble; at the same time, its heat dissipation performance has room for improvement, and under prolonged operation, localized high temperatures may occur. If this situation persists, it may affect the stable operation of the internal components. Utility Model Content

[0003] The purpose of this invention is to provide a photovoltaic junction box. This invention allows for convenient and quick installation of internal components and provides good heat dissipation, enabling the components to operate efficiently.

[0004] The technical solution of this utility model is as follows: A photovoltaic junction box includes a box body with a cover rotatably connected to it; a main control circuit board is provided inside the box body, and a core chip is provided on the main control circuit board; multiple positioning posts are provided inside the box body; multiple first positioning holes are provided on the main control circuit board, and the first positioning holes cooperate with the positioning posts; a first heat sink is provided above the main control circuit board, and the first heat sink is attached to the core chip; multiple heat sink fins are linearly distributed on the other side of the first heat sink; mounting blocks are provided on both sides of the inner wall of the box body, and the mounting blocks are provided with movable grooves. Triangular locking blocks are slidably connected in the movable grooves, and springs are provided between the triangular locking blocks and the inner wall of the movable grooves; the lower end of the triangular locking blocks abuts against the first heat sink; multiple heat dissipation holes are provided on the cover; multiple communication interfaces are provided on the rear side of the box body, and the communication interfaces are connected to the main control circuit board; a power interface is provided on the right side of the box body, and the power interface is connected to the main control circuit board via a wire.

[0005] In the aforementioned photovoltaic junction box, a second heat sink is provided between the main control circuit board and the bottom of the box body. The second heat sink is provided with multiple second positioning holes, which cooperate with positioning posts. The second heat sink is provided with multiple mesh holes. The second heat sink is attached to the bottom of the main control circuit board.

[0006] The aforementioned photovoltaic junction box has a mounting groove on the bottom outer side of the box body, and a third heat dissipation plate is installed in the mounting groove.

[0007] The aforementioned photovoltaic junction box has multiple mounting ears on the bottom outer side of the box body, and mounting holes are provided on the mounting ears.

[0008] The aforementioned photovoltaic junction box has a sealing ring between the edge of the first heat sink and the inner wall of the box.

[0009] The aforementioned photovoltaic junction box has grooves on both sides of the main control circuit board, the first heat sink, and the second heat sink, with the grooves corresponding to the mounting blocks.

[0010] The aforementioned photovoltaic junction box has a locking mechanism between the box body and the cover.

[0011] Compared with the prior art, the present invention has the following beneficial effects: 1. In this utility model, when installing internal components, the main control circuit board is first precisely aligned with the positioning post inside the box through the first positioning hole to achieve rapid positioning; then, the first heat sink is placed above the main control circuit board and attached to the core chip. During placement, the first heat sink contacts the inclined surface of the triangular locking block, pushing the triangular locking block to slide into the movable slot. After the first heat sink is fully in place, the triangular locking block returns to its original position under the action of the spring force, tightly abutting against the top of the first heat sink, thus simultaneously and securely fixing the main control circuit board and the first heat sink. The assembly process is convenient and efficient, significantly saving installation time. In terms of heat dissipation, the heat generated by the core chip during operation can be directly conducted to the tightly attached first heat sink. The heat dissipation fins on the first heat sink effectively increase the heat dissipation area and accelerate heat diffusion. At the same time, multiple heat dissipation holes on the box cover form an air circulation channel, allowing heat to be quickly discharged from the box, avoiding local high temperature accumulation, and ensuring the stable and efficient operation of the core chip, main control circuit board, and other components. The communication interface connects to the main control circuit board, allowing for flexible adaptation to external data acquisition devices, monitoring terminals, and other equipment, facilitating real-time transmission of junction box operation data. This enables staff to remotely monitor equipment status and promptly detect and handle anomalies. The power interface connects to the main control circuit board via wires, ensuring clear location and separate layout from the communication interface to avoid wire confusion or tangling during wiring, improving wiring convenience. It also ensures a stable electrical connection between the external power supply or photovoltaic system power supply line and the main control circuit board, guaranteeing reliable current transmission and further enhancing the junction box's functional adaptability and safety.

[0012] 2. In this utility model, the second heat sink precisely engages with the positioning post inside the box through its second positioning hole. This allows for precise alignment during installation with the main control circuit board and the first heat sink, while also ensuring stable contact with the bottom of the main control circuit board. This ensures that the heat generated at the bottom of the main control circuit board can be efficiently conducted to the second heat sink. Furthermore, the multiple mesh holes on the second heat sink reduce its own weight, avoiding increased load on the box, while also increasing the contact area with air, accelerating heat diffusion to the bottom of the box. The heat transferred to the bottom of the box can be further conducted to the third heat sink on the outer bottom of the box, and finally dissipated quickly to the external environment by the third heat sink. This overcomes the limitation of relying solely on the first heat sink for heat dissipation above the main control circuit board, achieving bidirectional heat dissipation on both the top and bottom surfaces of the main control circuit board. This more comprehensively avoids localized high temperature accumulation, further ensuring the stable operation of the main control circuit board and core chip, and significantly improving the overall heat dissipation performance and long-term reliability of the junction box. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the structure of this utility model; Figure 2 This is a schematic diagram of the bottom structure of this utility model; Figure 3 This is a structural diagram of the main control circuit board inside the box; Figure 4 This is a schematic diagram of the structure of the second heat sink inside the body.

[0014] The labels in the attached diagram are as follows: 1-box body, 2-box cover, 3-main control circuit board, 4-core chip, 5-positioning post, 6-first positioning hole, 7-first heat sink, 8-heat sink fins, 9-mounting block, 10-movable slot, 11-triangular locking block, 12-heat dissipation hole, 13-communication interface, 14-power interface, 15-second heat sink, 16-second positioning hole, 17-mesh, 18-mounting slot, 19-third heat sink, 20-mounting ear, 21-mounting hole, 22-sealing ring, 23-groove, 24-lock. Detailed Implementation

[0015] The present invention will be further described below with reference to the accompanying drawings and embodiments, but this should not be construed as limiting the present invention.

[0016] Example: A photovoltaic junction box, configured as follows Figure 1-4As shown, the device includes a box body 1, made of flame-retardant PC / ABS alloy, which serves to support all internal components and isolate them from the external environment, providing a safe protective space for the internal components. A lid 2 is hinged to the box body 1. The lid 2 is made of the same flame-retardant PC / ABS alloy as the box body 1, with reinforcing ribs on its surface. It seals the box body 1, aids in heat dissipation, and protects the internal components from dust and moisture. A latch 24 is provided between the box body 1 and the lid 2, which engages to secure the two components, enabling a detachable and sealed connection for easy maintenance and ensuring reliable sealing. Multiple positioning posts 5 are integrally formed inside the box body 1. Figure 4 As shown, the housing 1 contains a second heat sink 15, made of 6063 aluminum alloy, used to conduct heat from the bottom of the main control circuit board 3, achieving bidirectional heat dissipation. Aluminum alloy has excellent thermal conductivity, and the anodized layer enhances corrosion resistance. The second heat sink 15 has multiple second positioning holes 16, which cooperate with positioning posts 5 to position and install the second heat sink 15, ensuring precise contact with the main control circuit board 3. The second heat sink 15 also has multiple mesh holes 17, used to reduce weight and increase the heat dissipation area. While reducing its own weight to avoid increasing the load on the housing 1, it increases the contact area with the air inside the housing. The mesh hole 17 structure breaks the air boundary layer on the surface of the heat sink, increasing heat convection and diffusion, and improving the heat transfer effect to the bottom of the housing 1. Figure 3As shown, a main control circuit board 3 is located above the second heat sink 15. The main control circuit board 3 is made of FR-4 epoxy fiberglass board and is used for integrated circuits and core chip 4 to realize photovoltaic current collection, signal processing, and device communication. The core chip 4 is soldered and fixed on the main control circuit board 3. The core chip 4 can be an MPPT chip or a shutdown chip, used to control the operation of the junction box and data processing, ensuring stable current transmission and status monitoring. The bottom of the second heat sink 15 is tightly attached to the bottom of the main control circuit board 3 to directly conduct heat from the bottom of the main control circuit board 3 and avoid heat accumulation at the bottom. The main control circuit board 3 is provided with multiple first positioning holes 6. The first positioning holes 6 cooperate with the positioning posts 5 to position the main control circuit board 3 and ensure that it is accurately aligned with the second heat sink 15 and the first heat sink 7. The main control circuit board 3 is provided with a first heat sink 7, which is made of 5052 aluminum alloy. It is used to conduct the high heat generated by the core chip 4 and quickly dissipate the working heat of the core chip 4. The first heat sink 7 and the core chip 4 are closely attached to each other with thermal grease to fill the gaps, enhance heat conduction, and avoid air gaps from affecting the heat conduction efficiency. On the other side of the first heat sink 7, there are multiple heat dissipation fins 8 linearly distributed. The heat dissipation fins 8 are integrally formed with the first heat sink 7 to increase the heat dissipation area and accelerate the diffusion of heat into the air inside the box. The inner walls of the housing 1 are provided with mounting blocks 9 on both sides, which are integrally formed with the housing 1. Each mounting block 9 has a movable groove 10, within which a triangular locking block 11 is slidably connected. The triangular locking block 11, made of plastic, is used to clamp the first heat sink 7 and fix the main control circuit board 3 to the heat sink. A spring is provided between the triangular locking block 11 and the inner wall of the movable groove 10 to provide a reset force. The spring, when compressed, generates a restoring force, enabling the triangular locking block 11 to automatically reset, eliminating the need for screws and simplifying the installation process. The lower end of the triangular locking block 11 abuts against the first heat sink 7 to secure it and prevent loosening. The housing cover 2 has multiple ventilation holes 12 to expel hot air from the housing, forming an air convection channel. The rear side of the housing 1 has multiple communication interfaces 13, which use RJ45 or RS485 standard interfaces. These interfaces are connected to the main control circuit board 3 to transmit data on the junction box's operating status, facilitating remote monitoring. The right side of the housing 1 is equipped with a power interface 14. The power interface 14 uses a waterproof plug for electrical connection, allowing access to an external power source or output of photovoltaic current. The power interface 14 is connected to the main control circuit board 3 via a wire for current transmission, ensuring power supply and generation transmission. The power interface 14 and communication interface 13 are separated to avoid wiring confusion and improve wiring convenience. Figure 2As shown, the outer bottom of the box 1 is provided with a mounting groove 18, which is integrally formed with the box 1 and is used to install, fix and fit the third heat sink 19. The mounting groove 18 is provided with the third heat sink 19, which is made of copper alloy and is used to dissipate the heat conducted to the bottom of the box 1, completing the heat dissipation closed loop. The heat transferred to the bottom of the box 1 can be further conducted to the third heat sink 19 on the outer bottom of the box 1, and finally quickly dissipated to the external environment by the third heat sink 19. This makes up for the limitation of relying solely on the first heat sink 7 to dissipate heat above the main control circuit board 3, and achieves bidirectional heat dissipation on both the upper and lower surfaces of the main control circuit board 3, thus completely avoiding local high temperatures. Figure 2 As shown, the outer bottom of the box 1 is provided with multiple mounting ears 20, and the mounting ears 20 are provided with mounting holes 21 for bolts to pass through for mechanical fixing. A sealing ring 22 is provided between the edge of the first heat sink 7 and the inner wall of the box 1. The sealing ring 22 is made of silicone and is used to seal the internal space of the box 1. To a certain extent, it can prevent moisture and dust above the sealed box 1 from entering and contacting the main control circuit board 3, forming a certain waterproof and dustproof barrier. The main control circuit board 3, the first heat sink 7 and the second heat sink 15 are provided with grooves 23 on both sides. The grooves 23 correspond to the mounting block 9 and are used to avoid the mounting block 9, so that the main control circuit board 3, the first heat sink 7 and the second heat sink 15 can be properly placed into the box 1 and accurately positioned.

[0017] Working principle: Component Installation and Fixing: During installation, first, precisely align the second heat sink 15 with the positioning post 5 inside the housing 1 through the second positioning hole 16, and place it smoothly into the bottom of the housing 1; then, place the main control circuit board 3 above the second heat sink 15 through the first positioning hole 6 and the positioning post 5, ensuring that the bottom of the main control circuit board 3 is tightly attached to the second heat sink 15; subsequently, cover the main control circuit board 3 with the first heat sink 7, making the first heat sink 7 completely attached to the core chip 4. During placement, the edge of the first heat sink 7 presses against the inclined surface of the triangular clip 11, pushing it forward. The triangular locking block 11 slides into the movable slot 10 and compresses the spring. When the first heat sink 7 is fully in place, the spring returns to its original position and pushes the triangular locking block 11 out. Its lower end tightly abuts against the first heat sink 7, simultaneously achieving a stable fixation between the main control circuit board 3, the second heat sink 15, and the first heat sink 7. Assembly can be completed without screws, making the operation convenient and efficient. At the same time, the grooves 23 on both sides of each component avoid each other with the mounting blocks 9 on the inner wall of the box 1, ensuring that each component can be smoothly inserted without positional interference. Finally, the box cover 2 is closed and fixed by the latch 24 to complete the overall assembly.

[0018] During operation, the core chip 4 serves as the control core. On the one hand, it achieves electrical connection with external circuits through the power interface 14, completes the collection and transmission of DC power from the photovoltaic module, and ensures stable current output or reception of external power supply. On the other hand, it collects the junction box operation data in real time and transmits it to the external monitoring terminal through the communication interface 13 on the back end, so that staff can remotely monitor the equipment status and detect abnormalities in a timely manner.

[0019] In terms of heat dissipation, the heat generated by the core chip 4 is quickly dissipated through a two-way path: the heat from above is directly conducted to the tightly fitted first heat sink 7, and the heat dissipation fins 8 on the first heat sink 7 increase the contact area with the air inside the box, accelerating the diffusion of heat into the air inside the box. The hot air is then discharged upward through the heat dissipation holes 12 on the box cover 2, forming a convection circulation. The heat from below is conducted to the second heat sink 15 attached to the bottom of the main control circuit board 3, and the mesh holes 17 on the second heat sink 15 further increase the air contact area, accelerating the transfer of heat to the bottom of the box body 1. The heat from the bottom of the box body 1 is then conducted to the third heat sink 19 in the outer mounting slot 18, and finally dissipated to the external environment by the third heat sink 19. This achieves two-way heat dissipation on both the upper and lower sides of the main control circuit board 3, effectively avoiding the accumulation of local high temperatures.

Claims

1. A photovoltaic junction box, characterized in that: The device includes a box body (1), on which a lid (2) is rotatably connected; a main control circuit board (3) is provided inside the box body (1), and a core chip (4) is provided on the main control circuit board (3); multiple positioning posts (5) are provided inside the box body (1); multiple first positioning holes (6) are provided on the main control circuit board (3), and the first positioning holes (6) cooperate with the positioning posts (5); a first heat sink (7) is provided above the main control circuit board (3), and the first heat sink (7) is attached to the core chip (4); multiple heat sink fins (8) are linearly distributed on the other side of the first heat sink (7); the inner walls of the box body (1) are divided into two sections. A separate mounting block (9) is provided, and a movable groove (10) is provided on the mounting block (9). A triangular locking block (11) is slidably connected in the movable groove (10). A spring is provided between the triangular locking block (11) and the inner wall of the movable groove (10). The lower end of the triangular locking block (11) abuts against the first heat sink (7). A plurality of heat dissipation holes (12) are provided on the cover (2). A plurality of communication interfaces (13) are provided on the rear side of the box body (1). The communication interfaces (13) are connected to the main control circuit board (3). A power interface (14) is provided on the right side of the box body (1). The power interface (14) is connected to the main control circuit board (3) via a wire.

2. The photovoltaic junction box according to claim 1, characterized in that: A second heat sink (15) is provided between the main control circuit board (3) and the bottom of the box (1). The second heat sink (15) is provided with a plurality of second positioning holes (16), which cooperate with the positioning post (5). The second heat sink (15) is provided with a plurality of mesh holes (17). The second heat sink (15) is attached to the bottom of the main control circuit board (3).

3. The photovoltaic junction box according to claim 1, characterized in that: The outer bottom of the box (1) is provided with a mounting groove (18), and a third heat dissipation plate (19) is provided in the mounting groove (18).

4. The photovoltaic junction box according to claim 1, characterized in that: The outer bottom of the box (1) is provided with a plurality of mounting ears (20), and the mounting ears (20) are provided with mounting holes (21).

5. The photovoltaic junction box according to claim 1, characterized in that: A sealing ring (22) is provided between the edge of the first heat sink (7) and the inner wall of the box (1).

6. The photovoltaic junction box according to claim 2, characterized in that: The main control circuit board (3), the first heat sink (7) and the second heat sink (15) are provided with grooves (23) on both sides, and the grooves (23) correspond to the mounting block (9).

7. The photovoltaic junction box according to claim 1, characterized in that: A latch (24) is provided between the box body (1) and the box lid (2).

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