Photovoltaic junction box
By setting through-holes on the connecting pieces of the photovoltaic junction box, the pins and busbars can be directly connected, which solves the problem of high material cost of conductive sheets and achieves efficient heat dissipation and cost reduction.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- ZHEJIANG CHINT XINHUI PV CO LTD
- Filing Date
- 2025-05-09
- Publication Date
- 2026-05-01
AI Technical Summary
Existing photovoltaic junction boxes struggle to balance heat dissipation performance and cost, as the conductive sheets must both conduct electricity and dissipate heat, resulting in high material costs.
A through-hole is provided on the connector to allow the pins and busbars to make direct contact. The connector serves only as a heat sink and is made of non-conductive or weakly conductive material. The pins are embedded in the through-hole and filled with a conductive and thermally conductive welding medium.
It improves heat dissipation efficiency, reduces material costs, increases the contact area of pins and connectors, and enhances overall heat dissipation performance.
Smart Images
Figure CN224191902U_ABST
Abstract
Description
Photovoltaic junction box Technical Field
[0001] This utility model relates to the field of photovoltaic technology, and in particular to a photovoltaic junction box. Background Technology
[0002] The photovoltaic junction box is an important part of the photovoltaic module, serving the functions of connection and protection. Currently, a typical photovoltaic junction box generally includes cables, diodes, and two conductive plates. The two pins of the diode extend to the lower side of the two conductive plates and are connected to the corresponding conductive plates. The two busbars on the photovoltaic module extend to the upper side of the two conductive plates and are connected to the corresponding conductive plates.
[0003] Conductive sheets provide conductivity, allowing pins and busbars to be electrically connected. Cables can be connected to one of the pins to achieve electrical continuity between the cable, pin, and busbar. Diodes generate significant heat during bypass protection, reaching temperatures close to 200°C, requiring both reliable conduction and reliable heat dissipation. Because conductive sheets serve the dual purpose of conduction and heat dissipation, they must be made of conductive materials (such as copper), leading to increased costs. Summary of the Invention
[0004] The purpose of this invention is to provide a photovoltaic junction box that improves heat dissipation performance and reduces costs.
[0005] To achieve this objective, the present invention adopts the following technical solution:
[0006] A photovoltaic junction box is used to connect two busbars. The photovoltaic junction box includes a diode and two spaced-apart connecting pieces. The diode has two pins, which extend to the lower side of the two connecting pieces and are connected to the corresponding connecting pieces. The connecting ends of the two busbars extend to the upper side of the two connecting pieces and are connected to the corresponding connecting pieces, so that the two pins are electrically connected to the two busbars respectively.
[0007] At least one of the two connecting pieces is provided with a through-hole, and the pin corresponding to the connecting piece with the through-hole is embedded in the through-hole. The connecting end of the busbar corresponding to the connecting piece with the through-hole is connected to the connecting piece and is in direct contact with the pin.
[0008] As an alternative, the through-hole is filled with a conductive welding medium, and the connection ends of the pins and the busbar are welded to the welding medium.
[0009] As an alternative, the welding medium protrudes from the through-hole and forms a welding end face on the upper side of the connecting piece, and the connecting end of the busbar is welded to the welding end face.
[0010] As an alternative, after the pin is embedded in the through-hole, the pin deforms according to the shape of the through-hole.
[0011] As an alternative, the connecting piece is provided with a heat dissipation coating at least at the edge of the through-hole, and the pin is in contact with the heat dissipation coating.
[0012] As an alternative, the connecting piece has multiple spaced recessed grooves on the inner wall of the through opening.
[0013] As an alternative, both connecting pieces are provided with through holes, and the two pins are respectively embedded in the two through holes.
[0014] As an optional solution, the photovoltaic junction box also includes a cable and a conductive connector, one end of which is connected to one of the pins, and the other end of which is connected to the cable.
[0015] As an optional solution, the photovoltaic junction box further includes a bottom box and a cover plate. The bottom box is provided with a receiving cavity and a wire-passing hole communicating with the receiving cavity. The diode and the two connecting pieces are both disposed in the receiving cavity. The cable extends into the receiving cavity through the wire-passing hole and is connected to one of the pins. The cover plate is disposed on the bottom box to cover the receiving cavity.
[0016] As an alternative, the width of the through-hole is smaller than the diameter of the pin.
[0017] The beneficial effects of this utility model are:
[0018] The photovoltaic junction box provided by this utility model, by setting a through-hole on the connecting piece, allows the pins and busbars corresponding to the connecting piece with the through-hole to be located on both sides of the connecting piece and directly contacted through the through-hole, thereby achieving conductivity between the pins and busbars and improving heat dissipation efficiency. In addition, the connecting piece with the through-hole can be made of non-conductive or weakly conductive materials, so that the connecting piece only serves as a heat dissipation component, reducing costs. Furthermore, embedding the pins into the through-hole increases the contact area between the pins and the connecting piece, further improving heat dissipation performance. Attached Figure Description
[0019] Figure 1 is a structural schematic diagram of the photovoltaic junction box and busbar provided in an embodiment of the present invention;
[0020] Figure 2 is a structural schematic diagram of the photovoltaic junction box (without the cover plate) and busbar provided in the embodiment of this utility model;
[0021] Figure 3 is an exploded view of the photovoltaic junction box provided in an embodiment of the present invention;
[0022] Figure 4 is a cross-sectional view of the photovoltaic junction box provided in an embodiment of the present invention;
[0023] Figure 5 is an enlarged view of the structure at point A in Figure 4;
[0024] Figure 6 is a schematic diagram of the structure of the connecting piece after being filled with welding medium according to an embodiment of the present utility model;
[0025] Figure 7 is a schematic diagram of the structure of the connecting piece without welding medium in an embodiment of this utility model;
[0026] Figure 8 is a schematic diagram of the structure of the bottom box involved in the embodiment of this utility model;
[0027] Figure 9 is a structural schematic diagram of a conductive connector according to an embodiment of this utility model;
[0028] Figure 10 is a structural schematic diagram of another conductive connector involved in an embodiment of this utility model.
[0029] In the picture:
[0030] 100. Busbar; 101. Connecting end;
[0031] 1. Cables;
[0032] 2. Diode; 21. Pins;
[0033] 3. Connecting piece; 31. Through port; 311. Recessed groove; 32. Welding medium; 321. Welding end face;
[0034] 4. Conductive connector; 41. Riveting part; 42. Welding part; 43. Process groove;
[0035] 5. Base box; 51. Receiving cavity; 52. Wire hole; 53. Wire pressing groove;
[0036] 6. Cover plate;
[0037] 7. Seam clamps. Detailed Implementation
[0038] The embodiments of this utility model are described in detail below. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar parts or parts having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this utility model, and should not be construed as limiting this utility model.
[0039] In the description of this utility model, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection or a detachable connection; a mechanical connection or an electrical connection; a direct connection or an indirect connection through an intermediate medium; or the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.
[0040] In the description of this utility model, unless otherwise expressly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.
[0041] The technical solution of this utility model will be further described below with reference to the accompanying drawings and specific embodiments.
[0042] As shown in Figures 1-10, this embodiment of the present invention provides a photovoltaic junction box for connecting a busbar 100 of a photovoltaic module. The photovoltaic junction box is used to connect to two busbars 100.
[0043] The photovoltaic junction box includes a diode 2 and two spaced-apart connecting pieces 3. The diode 2 has two pins 21, which extend to the lower side of the two connecting pieces 3 and are connected to the corresponding connecting pieces 3. The connecting ends 101 of the two busbars 100 extend to the upper side of the two connecting pieces 3 and are connected to the corresponding connecting pieces 3.
[0044] Specifically, at least one of the two connecting pieces 3 is provided with a through port 31, and the pin 21 corresponding to the connecting piece 3 with the through port 31 is embedded in the through port 31. The connecting end 101 of the busbar 100 corresponding to the connecting piece 3 with the through port 31 is connected to the connecting piece 3 and is electrically connected to the pin 21 embedded in the through port 31.
[0045] This photovoltaic junction box, by setting a through-hole 31 on the connecting piece 3, allows the pin 21 and the busbar 100 corresponding to the connecting piece 3 with the through-hole 31 to be located on both sides of the connecting piece 3 and directly and tightly connected to each other through the through-hole 31, so as to realize the conductivity of the pin 21 and the busbar 100, thereby improving the heat dissipation efficiency. In addition, the connecting piece 3 with the through-hole 31 can be made of non-conductive or weakly conductive materials, so that the connecting piece 3 only serves as a heat dissipation component, reducing costs. Furthermore, the pin 21 being embedded in the through-hole 31 can increase the contact area between the pin 21 and the connecting piece 3, further improving the heat dissipation performance.
[0046] It should be noted that in order to achieve a conductive connection between another pin 21 and another bus 100, the connecting piece 3 without the through port 31 still needs to have conductive properties, so that after the pin 21 is connected to the connecting piece 3 on the lower side and the bus 100 is connected to the connecting piece 3 on the upper side, the other pin 21 and the other bus 100 are conductively connected through the connecting piece 3 due to the conductive properties of the connecting piece 3.
[0047] Optionally, in order to improve the overall heat dissipation performance of the photovoltaic junction box and reduce costs, each of the two connecting pieces 3 is provided with a through-hole 31, and the two pins 21 are respectively inserted into the through-hole 31 from the lower side of the two connecting pieces 3. The connecting ends 101 of the two busbars 100 are electrically connected to the two pins 21 from the upper side of the two connecting pieces 3.
[0048] Furthermore, as shown in Figures 4-6, after the pin 21 is embedded in the through-hole 31, the through-hole 31 is filled with a welding medium 32. The welding medium 32 can fully fill the gap between the pin 21 and the through-hole 31, so that the filling medium 32 forms a heat-conducting channel, increases the heat-conducting area, and improves the heat dissipation performance. After the welding medium 32 is filled, the pin 21 and the connecting piece 3 can be welded together to fix the pin 21. The connecting end 101 of the busbar 100 can be welded to the welding medium 32 to achieve the welding connection between the connecting end 101 of the busbar 100 and the connecting piece 3. The welding medium 32 has both electrical conductivity and thermal conductivity, so that the pin 21 and the busbar 100 can conduct electricity and improve the heat dissipation capacity of the pin 21.
[0049] Optionally, the welding medium 32 can be selected as tin or other hot fusion material. The molten tin or other hot fusion material is filled into the through-hole 31, so that the tin or other hot fusion material can automatically fill the gap and achieve the welding connection between the pin 21 and the connecting piece 3 after solidification.
[0050] Optionally, to facilitate welding of the connecting end 101 of the busbar 100 to the welding medium 32, when the welding medium 32 is filled into the through-hole 31, the welding medium 32 protrudes from the through-hole 31 and forms a welding end face 321 on the upper side of the connecting piece 3. The connecting end 101 of the busbar 100 is then welded to the welding end face 321. By making the welding medium 32 protrude from the through-hole 31, the welding area of the welding end face 321 can be increased, making it easier to weld the connecting end 101 of the busbar 100 to the welding end face 321, and also improving the weld strength.
[0051] Optionally, the width of the through-hole 31 is smaller than the diameter of the pin 21. During the process of inserting the pin 21 into the through-hole 31, a pressing method can be used to press the pin 21 into the through-hole 31. During pressing, the pin 21 can deform according to the shape of the through-hole 31, and the pin 21 can be deformed into a convex, I-shaped, or other structure to achieve a fixed connection with the connecting piece 3. By pressing, the contact area between the pin 21 and the through-hole 31 can be increased, thereby improving heat dissipation performance.
[0052] Optionally, as shown in Figure 7, the connecting piece 3 has a plurality of spaced recessed grooves 311 on the inner wall of the through-hole 31. When the pin 21 is pressed into the through-hole 31, the pin 21 deforms and fills the recessed grooves 311, further increasing the contact area between the pin 21 and the connecting piece 3 and improving heat dissipation performance. Moreover, when the pin 21 is pressed, it can also distribute the stress concentration caused by the processing of the connecting piece 3, reduce the deformation of the connecting piece 3, and improve the structural strength of the connecting piece 3.
[0053] Optionally, the connecting piece 3 may have a heat-dissipating coating (selected as a graphene layer or a tin layer) at least at the edge of the through-hole 31, and the pin 21 may be in contact with the heat-dissipating coating. The heat-dissipating coating can improve the thermal conductivity. Of course, the connecting piece 3 may also be coated with a heat-dissipating coating all over.
[0054] Referring to Figures 2-3 and Figure 8, in order to facilitate the electrical connection between the photovoltaic junction box and the photovoltaic module, the photovoltaic junction box also includes a cable 1. One end of the cable 1 is connected to pin 21, and the other end of the cable 1 is connected to the photovoltaic module.
[0055] The photovoltaic junction box also includes a bottom box 5 and a cover plate 6. The bottom box 5 is provided with a receiving cavity 51 and a wire hole 52 communicating with the receiving cavity 51. The diode 2 and two connecting pieces 3 are all located in the receiving cavity 51. The cable 1 extends into the receiving cavity 51 through the wire hole 52 and is connected to a pin 21. The cover plate 6 is placed on the bottom box 5 to cover the receiving cavity 51. The bottom box 5 can provide installation space for the connecting pieces 3 and can be fixed. The cover plate 6 can be used to prevent debris from falling into the receiving cavity 51.
[0056] In order to secure the cable 1, the photovoltaic junction box also includes a wire clamp 7. The wall of the through hole 52 is provided with a wire clamping groove 53, and the wire clamp 7 is placed in the wire clamping groove 53 and presses against the cable 1.
[0057] To facilitate the connection between cable 1 and pin 21, the photovoltaic junction box also includes a conductive connector 4, one end of which is connected to a pin 21, and the other end of which is connected to cable 1.
[0058] Optionally, the conductive connector 4 has two structures, as shown in Figure 9. One structure of the conductive connector 4 has a riveting part 41 at the other end, which is riveted to the cable 1. As shown in Figure 10, the other structure of the conductive connector 4 has a welding part 42 at the other end, which has a process groove 43. The process groove 43 can make the welding part 42 form a rib, which can facilitate resistance welding between the welding part 42 and the cable 1.
[0059] The photovoltaic junction box described above can be manufactured using the following method:
[0060] A through-hole 31 is made on the connecting piece 3;
[0061] The pin 21 of diode 2 is pressed into the through-hole 31 from the underside of the corresponding connecting piece 3. By pressing the pin 21 into the through-hole 31, the pin 21 deforms due to the squeezing action and is embedded in the through-hole 31.
[0062] Solder cable 1 to the corresponding pin 21;
[0063] Welding medium 32 is filled into the upper through-hole 31 of the connecting piece 3. The welding medium 32 protrudes from the through-hole 31 and forms a welding end face 321 on the upper side of the connecting piece 3 for welding with the busbar 100.
[0064] Understandably, before welding the busbar 100, the welded diode 2 and connecting piece 3 can be installed inside the base box 5; after welding the busbar 100, the cover plate 6 can be placed on the base box 5.
[0065] The photovoltaic junction box manufactured using the above method ensures that the connecting piece 3 does not conduct electricity but only serves for heat dissipation. This allows the connecting piece 3 to be made from inexpensive non-conductive or weakly conductive materials (such as iron or aluminum), reducing costs and improving heat dissipation performance. Furthermore, by pressing the pin 21 into the through-hole 31, the pin 21 deforms, increasing the contact area between the pin 21 and the connecting piece 3, further enhancing heat dissipation. Filling the through-hole 31 with the welding medium 32 not only fills the gap between the pin 21 and the through-hole 31 but also facilitates the welding of the busbar 100. By directly connecting the cable 1, diode 2, and busbar 100 through the welding medium 32, heat dissipation is effectively improved, the loop resistance within the base box 5 is reduced, and conductivity is increased.
[0066] 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 photovoltaic junction box for connecting two busbars (100), the photovoltaic junction box comprising a diode (2) and two spaced connecting pieces (3), the diode (2) having two pins (21), the two pins (21) extending to the lower side of the two connecting pieces (3) and connecting to the corresponding connecting pieces (3), the connecting ends (101) of the two busbars (100) extending to the upper side of the two connecting pieces (3) and connecting to the corresponding connecting pieces (3), so that the two pins (21) are electrically connected to the two busbars (100) respectively; characterized in that, At least one of the two connecting pieces (3) is provided with a through port (31), and the pin (21) corresponding to the connecting piece (3) with the through port (31) is embedded in the through port (31). The connecting end (101) of the busbar (100) corresponding to the connecting piece (3) with the through port (31) is connected to the connecting piece (3) and is in direct contact with the pin (21).
2. The photovoltaic junction box according to claim 1, characterized in that, The through-hole (31) is filled with a conductive welding medium (32), and the pin (21) and the connection end (101) of the busbar (100) are both welded to the welding medium (32).
3. The photovoltaic junction box according to claim 2, characterized in that, The welding medium (32) protrudes from the through-hole (31) and forms a welding end face (321) on the upper side of the connecting piece (3), and the connecting end (101) of the busbar (100) is welded to the welding end face (321).
4. The photovoltaic junction box according to claim 1, characterized in that, After the pin (21) is embedded in the through-hole (31), the pin (21) deforms according to the shape of the through-hole (31).
5. The photovoltaic junction box according to claim 1, characterized in that, The connecting piece (3) has a heat dissipation coating at least at the edge of the through-hole (31), and the pin (21) is in contact with the heat dissipation coating.
6. The photovoltaic junction box according to claim 1, characterized in that, The connecting piece (3) has a plurality of spaced recessed grooves (311) on the inner wall of the through opening (31).
7. The photovoltaic junction box according to claim 1, characterized in that, Both connecting pieces (3) are provided with through ports (31), and the two pins (21) are respectively embedded in the two through ports (31).
8. The photovoltaic junction box according to claim 1, characterized in that, The photovoltaic junction box also includes a cable (1) and a conductive connector (4), one end of which is connected to one of the pins (21), and the other end of which is connected to the cable (1).
9. The photovoltaic junction box according to claim 8, characterized in that, The photovoltaic junction box also includes a bottom box (5) and a cover plate (6). The bottom box (5) is provided with a receiving cavity (51) and a wire hole (52) communicating with the receiving cavity (51). The diode (2) and the two connecting pieces (3) are both disposed in the receiving cavity (51). The cable (1) extends into the receiving cavity (51) through the wire hole (52) and is connected to one of the pins (21). The cover plate (6) is disposed on the bottom box (5) to cover the receiving cavity (51).
10. The photovoltaic junction box according to claim 9, characterized in that, The width of the through-hole (31) is smaller than the diameter of the pin (21).