Photovoltaic junction box

Abstract

The invention belongs to the technical field of solar photovoltaics, and particularly discloses a photovoltaic junction box. According to the photovoltaic junction box provided by the invention, the pin of the diode and one end of the terminal are welded with the welding part of the heat dissipation piece through electric resistance welding, and heat generated when the diode works can be transmitted to the heat dissipation piece through the pin of the diode and is dissipated through the heat dissipation piece, so that the heat dissipation efficiency when the diode works is improved; therefore, the heat dissipation performance of the photovoltaic junction box is improved, and the heat dissipation pieces also play a role in fixing and supporting the pins and the terminals of the diodes. One end of the terminal is conductively connected with the pin of the diode, the other end of the terminal is welded with the bus bar through laser welding, the terminal plays a role in middle transition connection, the terminal does not need to play a main role in heat dissipation, the size of the terminal can be relatively reduced, the structure of the terminal is simplified, the bus bar is connected with the terminal through laser welding, tin soldering is replaced, and the cost is reduced. And the tin welding cost is saved, so that the production cost is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of solar photovoltaic technology, and particularly to a photovoltaic junction box. Background Art

[0002] A photovoltaic junction box is a connector between a photovoltaic cell array composed of photovoltaic cell modules and a photovoltaic cell charging control device. Its main function is to connect and protect solar photovoltaic modules, connect the electricity generated by photovoltaic cells to external circuits, and export the electric energy generated by photovoltaic cell modules through cables.

[0003] Traditional photovoltaic junction boxes usually include parts such as a base, terminals, diodes, and a box cover. The pins of the diodes are welded to the terminals, then the diodes with welded terminals are placed into the base, and then the bus bars are welded to the terminals. Finally, glue is poured into the base, and the box cover is buckled onto the base. In the photovoltaic junction box of the prior art, the heat generated when the diodes work is dissipated through the terminals, and the heat dissipation efficiency is low, thus resulting in poor heat dissipation performance of the photovoltaic junction box. Summary of the Invention

[0004] The purpose of the present invention is to provide a photovoltaic junction box, which improves the heat dissipation efficiency when the diodes work, and thus enhances the heat dissipation performance of the photovoltaic junction box.

[0005] To achieve this purpose, the present invention adopts the following technical solutions:

[0006] A photovoltaic junction box, comprising:

[0007] A diode;

[0008] Terminals;

[0009] A heat dissipation member, the heat dissipation member includes a welding part, one ends of the pins of the diode and one ends of the terminals are both welded to the welding part by resistance welding, and the pins of the diode are electrically connected to the terminals, and the other ends of the terminals are used for welding with bus bars by laser welding.

[0010] As an optional technical solution of the above photovoltaic junction box, the welding part includes a welding plate, the welding plate, the pins of the diode and the terminals are stacked, and the pins of the diode or the terminals are welded to one side surface of the welding plate.

[0011] As an optional technical solution of the above photovoltaic junction box, a plurality of grooves are arranged at intervals on one side surface of the welding plate for welding with the pins of the diode or the terminals.

[0012] As an optional technical solution of the above photovoltaic junction box, first heat dissipation plates are arranged on both opposite sides of the welding part, and the first heat dissipation plates extend towards the side away from the welding surface of the welding part and the pins of the diode.

[0013] As an alternative technical solution of the above photovoltaic junction box, the heat dissipation member further includes a connecting portion, one end of the connecting portion is connected to one end of the welding portion, second heat dissipation plates are provided on both opposite sides of the connecting portion, the second heat dissipation plates are arranged at an angle with the connecting portion, and the second heat dissipation plates extend in a direction away from the connecting portion, the other end of the terminal is placed between the two second heat dissipation plates, and the second heat dissipation plates are arranged higher than the other end of the terminal.

[0014] As an alternative technical solution of the above photovoltaic junction box, the photovoltaic junction box further includes a base, the heat dissipation member is arranged in the base, and the connecting portion is attached to the bottom wall of the base;

[0015] And / or, the projected area of the connecting portion on the bottom wall of the base is larger than the projected area of the welding portion on the bottom wall of the base.

[0016] As an alternative technical solution of the above photovoltaic junction box, a third heat dissipation plate is provided at the other end of the connecting portion, the third heat dissipation plate is arranged at an angle with the connecting portion, and the third heat dissipation plate extends in a direction away from the connecting portion, the third heat dissipation plate is arranged higher than the other end of the terminal.

[0017] As an alternative technical solution of the above photovoltaic junction box, the terminal includes a resistance welding connection portion and a laser welding connection portion connected to the resistance welding connection portion, the resistance welding connection portion is welded to the welding portion and is electrically connected to the pin of the diode, and the laser welding connection portion is used for welding with the bus bar.

[0018] As an alternative technical solution of the above photovoltaic junction box, the terminal further includes a cable connection portion, the cable connection portion is connected to the laser welding connection portion, and the cable connection portion is arranged opposite to the resistance welding connection portion, and a cable is electrically connected to the cable connection portion.

[0019] As an alternative technical solution of the above photovoltaic junction box, the resistance welding connection portion includes a plurality of connecting plates arranged at intervals, one end of the connecting plate is connected to the laser welding connection portion, and the connecting plate is placed between the welding portion and the pin of the diode.

[0020] As an alternative technical solution of the above photovoltaic junction box, the laser welding connection portion is in a plate-like structure, one end of the connecting plate is bent and connected to one end of the laser welding connection portion, and one side surface of the laser welding connection portion is used for fitting and welding with the bus bar.

[0021] As an alternative technical solution of the above photovoltaic junction box, both the resistance welding connection part and the laser welding connection part are in a plate-like structure, the resistance welding connection part and the laser welding connection part are coplanar, and the pin of the diode is placed between the resistance welding connection part and the welding part.

[0022] Advantages of the present invention:

[0023] For the photovoltaic junction box provided by the present invention, one end of the pin of the diode and one end of the terminal are both welded to the welding part of the heat dissipation part by resistance welding. When the diode works, the heat generated can be transferred to the heat dissipation part through the pin of the diode and dissipated through the heat dissipation part, improving the heat dissipation efficiency when the diode works, and then enhancing the heat dissipation performance of the photovoltaic junction box. Moreover, the heat dissipation part also plays a role in fixing and supporting the pins of the diode and the terminal; one end of the terminal is electrically connected to the pin of the diode, and the other end of the terminal is welded to the bus bar by laser welding. The terminal plays an intermediate transition connection role. The terminal does not need to bear the main heat dissipation function, so the size of the terminal can be relatively reduced, and the structure of the terminal can be simplified. In addition, the bus bar is connected to the terminal by laser welding, replacing soldering, saving the cost of welding tin, and thus reducing the production cost. In addition, the heat generated when the diode works can also be conducted to the bus bar and taken out of the photovoltaic junction box by the heat-conducting bus bar, playing an efficient heat dissipation role. Description of the drawings

[0024] Figure 1 is an exploded view of a positive-type photovoltaic junction box provided by an embodiment of the present invention;

[0025] Figure 2 is a schematic structural diagram of the connection between the heat dissipation part, the terminal and the diode provided by an embodiment of the present invention;

[0026] Figure 3 is a schematic structural diagram of the interior of the base provided by an embodiment of the present invention;

[0027] Figure 4 is a schematic structural diagram of the base filled with insulating glue provided by an embodiment of the present invention;

[0028] Figure 5 is a schematic structural diagram of the base with a box cover buckled thereon provided by an embodiment of the present invention;

[0029] Figure 6 is a schematic structural diagram of a heat dissipation part provided by an embodiment of the present invention;

[0030] Figure 7 is another schematic structural diagram of a heat dissipation part provided by an embodiment of the present invention;

[0031] Figure 8 is a first schematic structural diagram of a terminal provided by an embodiment of the present invention;

[0032] Figure 9 is the second structural schematic diagram of the terminal provided by the embodiment of the present invention;

[0033] Figure 10 is the front view of the second structure of the terminal provided by the embodiment of the present invention;

[0034] Figure 11 is the third structural schematic diagram of the terminal provided by the embodiment of the present invention;

[0035] Figure 12 is the fourth structural schematic diagram of the terminal provided by the embodiment of the present invention;

[0036] Figure 13 is the front view of the fourth structure of the terminal provided by the embodiment of the present invention;

[0037] Figure 14 is the connection structural schematic diagram of the diode, connection plate and welding part provided by the embodiment of the present invention;

[0038] Figure 15 is the cross-sectional view of an internal structure of the base provided by the embodiment of the present invention;

[0039] Figure 16 is the exploded view of a photovoltaic junction box of an intermediate pole type provided by the embodiment of the present invention;

[0040] Figure 17 is the exploded view of a photovoltaic junction box of a negative pole type provided by the embodiment of the present invention;

[0041] Figure 18 is the connection structural schematic diagram of the resistance welding connection part, diode and welding part provided by the embodiment of the present invention;

[0042] Figure 19 is another structural schematic diagram of the connection of the heat dissipation part, terminal and diode provided by the embodiment of the present invention;

[0043] Figure 20 is the cross-sectional view of another internal structure of the base provided by the embodiment of the present invention;

[0044] Figure 21 is the exploded view of another photovoltaic junction box of an intermediate pole type provided by the embodiment of the present invention;

[0045] Figure 22 is the exploded view of another photovoltaic junction box of a positive pole type provided by the embodiment of the present invention;

[0046] Figure 23 is the exploded view of another photovoltaic junction box of a negative pole type provided by the embodiment of the present invention.

[0047] In the figure:

[0048] 1. Diode; 2. Heat sink; 3. Terminal; 4. Bus bar; 5. Cable; 6. Base; 7. Lid; 8. Pressing buckle; 9. Insulating glue;

[0049] 21. Welding part; 211. Groove; 22. First heat sink plate; 23. Connection part; 24. Second heat sink plate; 25. Third heat sink plate;

[0050] 31. Resistance welding connection part; 311. Connection plate; 32. Laser welding connection part; 33. Cable connection part. Detailed implementation mode

[0051] The present invention will be further described in detail below with reference to the drawings and embodiments. It can be understood that the specific embodiments described herein are only used to explain the present invention, rather than limiting the present invention. In addition, it should be noted that for the convenience of description, only the parts related to the present invention are shown in the drawings, rather than all the structures.

[0052] In the description of the present invention, unless otherwise clearly defined and limited, the terms "connected", "connected" and "fixed" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated; it can be a mechanical connection or an electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, and it can be the communication inside two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0053] In the present invention, unless otherwise clearly defined and limited, the first feature being "above" or "below" the second feature may include the direct contact between the first and second features, or may include that the first and second features are not in direct contact but in contact through other features between them. Moreover, the first feature being "above", "above" and "on" the second feature includes that the first feature is directly above and obliquely above the second feature, or only means that the first feature has a higher horizontal height than the second feature. The first feature being "below", "below" and "under" the second feature includes that the first feature is directly below and obliquely below the second feature, or only means that the first feature has a lower horizontal height than the second feature.

[0054] In the description of this embodiment, the orientation or positional relationships such as "above", "below", "right", etc. are based on the orientation or positional relationships shown in the drawings, and are only for the convenience of description and simplifying the operation, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to the present invention. In addition, the terms "first" and "second" are only used for distinction in description and have no special meanings.

[0055] AsFigures 1 to 3 As shown, this embodiment provides a photovoltaic junction box, which includes a diode 1, a terminal 3 and a heat sink 2. The heat sink 2 includes a welding portion 21, and the pin of the diode 1 and one end of the terminal 3 are both welded to the welding portion 21 by resistance welding, and the pin of the diode 1 is conductively connected to the terminal 3. The other end of the terminal 3 is used to be welded to the busbar 4 by laser welding. The pin of the diode 1 and one end of the terminal 3 are both welded to the welding part 21 of the heat sink 2 by resistance welding. The heat generated by the diode 1 when working can be transferred to the heat sink 2 through the pin of the diode 1 and dissipated through the heat sink 2, thereby improving the heat dissipation efficiency of the diode 1 when working, thereby improving the heat dissipation performance of the photovoltaic junction box, and the heat sink 2 also plays a role in fixing and supporting the pin of the diode 1 and the terminal 3; one end of the terminal 3 is conductively connected to the pin of the diode 1, and the other end of the terminal 3 is welded to the busbar 4 by laser welding, and the terminal 3 plays the role of an intermediate transition connection. The terminal 3 does not need to bear the main heat dissipation role, which can relatively reduce the size of the terminal 3 and simplify the structure of the terminal 3. The busbar 4 is connected to the terminal 3 by laser welding, instead of tin soldering, saving the cost of welding tin, thereby reducing the production cost. In addition, the heat generated by the diode 1 when working can also be conducted to the busbar 4, and the busbar 4 conducts the heat out of the photovoltaic junction box, which plays a role in efficient heat dissipation.

[0056] The diode 1 has two pins, and each pin of the diode 1 is respectively provided with a heat sink 2, a terminal 3 and a busbar 4, so that the current flows through the first busbar 4, the first terminal 3, the first pin of the diode 1, the diode 1, the second pin of the diode 1, the second terminal 3 and the second busbar 4 in sequence.

[0057] See also Figure 3 As shown, the photovoltaic junction box also includes a base 6, the diode 1 and the heat sink 2 are arranged in the base 6, the bottom of the base 6 is provided with a through hole, one end of the busbar 4 is penetrated by the through hole and connected to the other end of the terminal 3. Specifically, in combination Figures 1 to 3 As shown, one end of the busbar 4 is bent into a U-shaped structure, the busbar 4 is placed on the upper surface of the terminal 3, and is welded to the terminal 3 by laser welding to achieve a conductive connection between the busbar 4 and the terminal 3, thereby achieving an electrical connection between the photovoltaic junction box and the photovoltaic cell. During assembly, the pins of the diode 1, the terminal 3 and the welding portion 21 of the heat sink 2 are first welded by resistance welding, and then the welded diode 1, the terminal 3 and the heat sink 2 are placed in the base 6. When the photovoltaic junction box is used, one end of the busbar 4 is penetrated by a through hole and is welded to the other end of the terminal 3 by laser welding. Since the busbar 4 covers the upper surface of the terminal 3, laser welding is used instead of soldering to weld the busbar 4. While reducing production costs, it is also convenient to weld the busbar 4 to the terminal 3.

[0058] like Figure 4As shown, the base 6 is filled with insulating glue 9. The heat generated when the diode 1 works can be dissipated to the outside of the photovoltaic junction box through the heat sink 2, the insulating glue 9, and the side wall of the base 6 in sequence. Moreover, the insulating glue 9 also plays a role in fixing the diode 1, the heat sink 2, the terminal 3, and the bus bar 4.

[0059] As Figure 5 shown, the photovoltaic junction box further includes a box cover 7. After the insulating glue 9 is filled in the base 6, the box cover 7 is buckled onto the base 6 to protect the insulating glue 9 in the base 6.

[0060] Combined Figure 2 and Figure 6 shown, in order to improve the connection strength between the pin of the diode 1 or the terminal 3 and the welding part 21, in some embodiments, the welding part 21 includes a welding plate. The welding plate, the pin of the diode 1, and the terminal 3 are stacked, and the pin of the diode 1 or the terminal 3 is welded to the surface of the welding plate on the side with the groove 211, increasing the welding area between the pin of the diode 1, the terminal 3, and the welding plate, and improving the connection reliability between the pin of the diode 1 or the terminal 3 and the welding part 21.

[0061] Further optionally, the surface of the welding plate for welding with the pin of the diode 1 or the terminal 3 is provided with a plurality of grooves 211 at intervals. During resistance welding, the molten metal liquid flows into the grooves 211, further improving the connection strength between the pin of the diode 1 or the terminal 3 and the welding part 21.

[0062] As Figure 6 and Figure 7 shown, first heat dissipation plates 22 are provided on both opposite sides of the welding part 21. The first heat dissipation plates 22 extend toward the side away from the welding surface between the welding part 21 and the pin of the diode 1. The heat generated when the diode 1 works is transferred to the first heat dissipation plates 22 through the pin of the diode 1 and the welding part 21, and then dissipated to the outside through the insulating glue 9 and the side wall of the base 6, further improving the heat dissipation performance of the photovoltaic junction box. Optionally, the first heat dissipation plates 22 are connected to the edges of the welding plates of the welding part 21, and the first heat dissipation plates 22 are perpendicular to the welding plates, so as to facilitate the installation of the heat sink 2 into the base 6 without affecting the connection between the pin of the diode 1 and the welding plate. In addition, the first heat dissipation plates 22 also play a role in shielding. During the process of resistance welding, the first heat dissipation plates 22 can block the molten metal liquid from flowing to both sides, reducing the loss of the metal liquid and ensuring the effective welding area.

[0063] The heat dissipation component 2 further includes a connecting portion 23. One end of the connecting portion 23 is connected to one end of the welding portion 21. Second heat dissipation plates 24 are provided on both opposite sides of the connecting portion 23. The second heat dissipation plates 24 are arranged at an angle with the connecting portion 23, and the second heat dissipation plates 24 extend in a direction away from the connecting portion 23. The other end of the terminal 3 is placed between the two second heat dissipation plates 24, and the second heat dissipation plates 24 are arranged higher than the other end of the terminal 3. The heat generated when the diode 1 works can also be dissipated through the connecting portion 23 and the two second heat dissipation plates 24. The heat can be dissipated to the outside through the connecting portion 23, the insulating glue 9 and the bottom wall of the base 6. The heat can also be dissipated to the outside through the connecting portion 23, the two second heat dissipation plates 24, the insulating glue 9 and the side wall of the base 6, further improving the heat dissipation performance of the photovoltaic junction box. When laser welding the bus bar 4, the second heat dissipation plates 24 can also block the welding metal sparks from splashing outward, protecting other components inside the photovoltaic junction box from damage, preventing the inside of the base 6 from being burned, and reducing the dielectric strength of the bonding area between the inner wall of the base 6 and the insulating glue 9 after the insulating glue 9 is potted in the base 6. The connecting portion 23 can be a plate-like structure. One end of the connecting portion 23 is connected to one end of the welding plate, and the area of the connecting portion 23 is larger than that of the welding plate to increase the heat dissipation area as much as possible. The second heat dissipation plates 24 are connected to the edge of the connecting portion 23, and the second heat dissipation plates 24 are perpendicular to the connecting portion 23 to facilitate the installation of the heat dissipation component 2 into the base 6. The heat dissipation component 2 is arranged in the base 6, and the connecting portion 23 is attached to the bottom wall of the base 6. The connecting portion 23 serves as the main heat dissipation part of the heat dissipation component 2, and the connecting portion 23 is arranged close to the bottom wall of the base 6 to improve the heat dissipation efficiency.

[0064] Further, the projected area of the connecting portion 23 on the bottom wall of the base 6 is larger than the projected area of the welding portion 21 on the bottom wall of the base 6, and the connecting portion 23 plays a main heat dissipation role.

[0065] Further optionally, as Figure 7 shown, a third heat dissipation plate 25 is provided at the other end of the connecting portion 23. The third heat dissipation plate 25 is arranged at an angle with the connecting portion 23, and the third heat dissipation plate 25 extends in a direction away from the connecting portion 23. The third heat dissipation plate 25 is arranged higher than the other end of the terminal 3. The heat generated when the diode 1 works can be dissipated to the outside through the connecting portion 23, the third heat dissipation plate 25, the insulating glue 9 and the side wall of the base 6, further improving the heat dissipation performance of the photovoltaic junction box. When laser welding the bus bar 4, the third heat dissipation plate 25 can also block the welding metal sparks from splashing outward, protecting other components inside the photovoltaic junction box from damage, preventing the inside of the base 6 from being burned, and reducing the dielectric strength of the bonding area between the inner wall of the base 6 and the insulating glue 9 after the insulating glue 9 is potted in the base 6. The third heat dissipation plate 25 can be connected to the edge of the connecting portion 23, and the third heat dissipation plate 25 is perpendicular to the connecting portion 23 to facilitate the installation of the heat dissipation component 2 into the base 6.

[0066] As Figures 8 to 13As shown, in some embodiments, the terminal 3 includes a resistance welding connection portion 31 and a laser welding connection portion 32 connected to the resistance welding connection portion 31, the resistance welding connection portion 31 is welded to the welding portion 21 and is conductively connected to the pin of the diode 1, and the laser welding connection portion 32 is welded to the busbar 4. The resistance welding connection portion 31 can be placed between the pin of the diode 1 and the welding portion 21, or the pin of the diode 1 is placed between the resistance welding connection portion 31 and the welding portion 21. The setting of this structure can reduce the distance between the busbar 4 and the diode 1, thereby improving the conductivity between the busbar 4 and the diode 1.

[0067] Further optionally, if Figure 9 , Figure 10 , Figure 12 and Figure 13 As shown, the terminal 3 also includes a cable connection portion 33, the cable connection portion 33 is connected to the laser welding connection portion 32, and the cable connection portion 33 is arranged opposite to the resistance welding connection portion 31, and the cable connection portion 33 is conductively connected to the cable 5. The cable 5 is used to connect to the circuit outside the photovoltaic junction box, thereby realizing the connection between the photovoltaic junction box and the external circuit.

[0068] See also Figure 1 As shown, the cable 5 passes through the side wall of the base 6, one end of the cable 5 is placed inside the base 6 and connected to the cable connection part 33, and the other end of the cable 5 is placed outside the base 6 for connecting to an external circuit. The side wall of the base 6 is opened for the cable 5 to pass through, and the base 6 is also connected to a wire buckle 8, which is connected to the outer wall of the base 6 to cooperate with the base 6 to fix the cable 5 on the base 6, so as to prevent the cable 5 from being dragged and desoldering from the cable connection part 33.

[0069] In one practicable manner, continue to see Figures 8 to 10 As shown, the resistance welding connection part 31 includes a plurality of connection plates 311 arranged at intervals, and one end of the connection plate 311 is connected to the laser welding connection part 32. Figure 14 and Figure 15 As shown, the connecting plate 311 is placed between the welding portion 21 and the pin of the diode 1. Optionally, the connecting plate 311 can be inserted into the groove 211 of the welding plate. During resistance welding, the molten metal liquid can fill the groove 211 and the space between the connecting plate 311 and the pin of the diode 1, thereby improving the reliability of the connection between the welding plate, the connecting plate 311 and the pin of the diode 1.

[0070] The grooves 211 can be divided into two types. The inner diameter of one type of groove 211 is larger than that of the other type of groove 211 . The groove 211 with a larger inner diameter matches the size of the connecting plate 311 .

[0071] like Figure 8 and Figure 9As shown, the laser welding connection part 32 is a plate-like structure. One end of the connecting plate 311 is bent and connected to one end of the laser welding connection part 32. The bus bar 4 is attached to and welded to one side surface of the laser welding connection part 32. The laser welding connection part 32 and the connecting plate 311 are not in the same plane, so as to facilitate the welding of the laser welding connection part 32 and the bus bar 4, and the pin of the diode 1 connected to the connecting plate 311 will not interfere with the bus bar 4.

[0072] For the terminal 3 with the cable connection part 33, the cable connection part 33 is a plate-like structure. One end of the cable connection part 33 is bent and connected to the other end of the laser welding connection part 32. The cable connection part 33 is arranged higher than the laser welding connection part 32. The resistance welding connection part 31, the laser welding connection part 32 and the cable connection part 33 form a stepped shape to facilitate the welding of the cable connection part 33 and the cable 5. In order to improve the reliability of the connection between the cable 5 and the cable connection part 33, a convex rib is provided on the side of the cable connection part 33 where it is connected to the cable 5. Optionally, the width of the cable connection part 33 is smaller than that of the laser welding connection part 32, reducing the production cost and meeting the stable connection between the cable 5 and the cable connection part 33. The width of the laser welding connection part 32 is equal to that of the resistance welding connection part 31, ensuring the reliability of the connection between the bus bar 4 and the laser welding connection part 32, and the reliability of the connection between the pin of the diode 1 and the resistance welding connection part 31.

[0073] Both the terminal 3 composed of the resistance welding connection part 31 and the laser welding connection part 32 or the terminal 3 composed of the resistance welding connection part 31, the laser welding connection part 32 and the cable connection part 33 are integrally formed structures, and the stepped-shaped terminal 3 can be formed by stamping process.

[0074] In this embodiment, the terminal 3 has two structural forms, as Figure 8 shown. The structure of the first terminal includes the resistance welding connection part 31 and the laser welding connection part 32. The structures of the resistance welding connection part 31 and the laser welding connection part 32 are as described above, and the terminal 3 does not need to be connected to the cable 5. The structure of this terminal corresponds to the first heat sink 2 as Figure 7 shown. The structure of the first heat sink 2 includes a welding part 21, a connecting part 23, a first heat dissipation plate 22, a second heat dissipation plate 24 and a third heat dissipation plate 25.

[0075] As Figure 9 shown, the structure of the second terminal 3 includes the resistance welding connection part 31, the laser welding connection part 32 and the cable connection part 33. The structures of the resistance welding connection part 31, the laser welding connection part 32 and the cable connection part 33 are as described above. The structure of this terminal 3 corresponds to the second heat sink 2 as Figure 6 shown. The structure of the second heat sink 2 includes a welding part 21, a connecting part 23, a first heat dissipation plate 22 and a second heat dissipation plate 24. The third heat dissipation plate 25 is not provided, providing an avoidance space for the cable connection part 33 to connect the cable 5.

[0076] There are three types of photovoltaic junction boxes, namely the positive junction box, the intermediate junction box, and the negative junction box.

[0077] As Figure 16 shown, for the intermediate junction box, the cable 5 does not need to be set in the junction box. In order to improve the heat dissipation performance of the junction box, the first type of terminal 3 and the first type of heat sink 2 are set in the junction box.

[0078] Figure 1 is an exploded view of the positive junction box, Figure 17 is an exploded view of the negative junction box. As Figure 1 and Figure 17 shown, for the positive junction box and the negative junction box, the cable 5 needs to be set in the junction box. One of the terminals 3 in the junction box is the first type of terminal 3, the heat sink 2 is the first type of heat sink 2, the other terminal 3 is the second type of terminal 3, and the heat sink 2 is the second type of heat sink 2.

[0079] In another implementable manner, as Figure 11 , Figure 12 , Figure 18 , Figure 19 and Figure 20 shown, both the resistance welding connection part 31 and the laser welding connection part 32 are plate-like structures. The resistance welding connection part 31 and the laser welding connection part 32 are coplanar. The pin of the diode 1 is placed between the resistance welding connection part 31 and the welding part 21. After the pin of the diode 1 is welded to the resistance welding connection part 31, it is also convenient for the bus bar 4 to be welded to the laser welding connection part 32, which is convenient for assembly.

[0080] As Figure 12 shown, for the terminal 3 with the cable connection part 33, the cable connection part 33 is a plate-like structure. One end of the cable connection part 33 is bent and connected to the other end of the laser welding connection part 32. The cable connection part 33 is arranged higher than the laser welding connection part 32. The laser welding connection part 32 and the cable connection part 33 form a stepped shape to facilitate the welding of the cable connection part 33 and the cable 5. In order to improve the reliability of the connection between the cable 5 and the cable connection part 33, a convex rib is provided on the side where the cable connection part 33 is connected to the cable 5. Optionally, the width of the cable connection part 33 is smaller than that of the laser welding connection part 32, which reduces the production cost and only needs to meet the stable connection between the cable 5 and the cable connection part 33. The width of the laser welding connection part 32 is equal to that of the resistance welding connection part 31 to ensure the reliability of the connection between the bus bar 4 and the laser welding connection part 32, and the reliability of the connection between the pin of the diode 1 and the resistance welding connection part 31.

[0081] The resistance welding connection part 31 and the laser welding connection part 32 that form the terminal 3, or the terminal 3 formed by the resistance welding connection part 31, the laser welding connection part 32, and the cable connection part 33, are all integrally formed structures, and the stepped terminal 3 can be formed by stamping process.

[0082] In this implementation, the terminal has two structural forms. For example, Figure 11 As shown, the structure of the first type of terminal 3 includes a resistance welding connection part 31 and a laser welding connection part 32. The structures of the electronic welding connection part 31 and the laser welding connection part 32 are as described above, and the terminal 3 does not need to be connected to the cable 5. The structure of this terminal 3 corresponds to the first type of heat sink 2 as shown in Figure 7 As shown, the structure of the first type of heat sink 2 includes a welding part 21, a connection part 23, a first heat dissipation plate 22, a second heat dissipation plate 24, and a third heat dissipation plate 25.

[0083] For example, Figure 12 As shown, the structure of the second type of terminal 3 includes a resistance welding connection part 31, a laser welding connection part 32, and a cable connection part 33. The structures of the resistance welding connection part 31, the laser welding connection part 32, and the cable connection part 33 are as described above. The structure of this terminal 3 corresponds to the second type of heat sink 2 as shown in Figure 6 As shown, the structure of the second type of heat sink 2 includes a welding part 21, a connection part 23, a first heat dissipation plate 22, and a second heat dissipation plate 24. The absence of the third heat dissipation plate 25 provides a clearance space for the cable connection part 33 to connect the cable 5.

[0084] There are three types of photovoltaic junction boxes, namely the positive terminal junction box, the intermediate terminal junction box, and the negative terminal junction box.

[0085] For example, Figure 21 As shown, for the intermediate terminal junction box, the cable 5 does not need to be set in the junction box. In order to improve the heat dissipation performance of the junction box, the first type of terminal 3 and the first type of heat sink 2 as described above are set in the junction box.

[0086] For example, Figure 22 and Figure 23 As shown, for the positive terminal junction box and the negative terminal junction box, the cable 5 needs to be set in the junction box. One of the terminals 3 in the junction box is the first type of terminal 3 as described above, the heat sink 2 is the first type of heat sink 2, the other terminal 3 is the second type of terminal 3 as described above, and the heat sink 2 is the second type of heat sink 2.

[0087] The material of the above-mentioned heat sink 2 is a heat-conducting material to improve the heat dissipation efficiency. In the present invention, the heat sink 2 only functions to dissipate heat and support the pins of the diode 1, and does not play a conductive role. Therefore, the heat sink 2 can not only be made of copper, but also other materials with good heat dissipation effects such as steel and aluminum. Compared with copper, the material cost is lower, thereby reducing the production cost of the photovoltaic junction box. The terminal 3 realizes the conductive connection between the pins of the diode 1 and the bus bar 4, or the conductive connection between the cable 5 and the pins of the diode 1. Therefore, the material of the terminal 3 is copper. Since the terminal 3 does not need to play a heat dissipation role, the size of the terminal 3 can be smaller than that of the terminal in the prior art. Heat dissipation is carried out through the provided heat sink 2, and the heat sink 2 can use materials such as steel or aluminum with a lower cost than copper, thereby reducing the production cost of the photovoltaic junction box.

[0088] The heat sink 2 is an integrally formed structure, and usually adopts a stamping process to form a welded part 21, a connecting part 23, a first heat sink 22 and a second heat sink 24 that are integrally connected, or a welded part 21, a connecting part 23, a first heat sink 22, a second heat sink 24 and a third heat sink 25 that are integrally connected.

[0089] Obviously, the above-mentioned embodiments of the present invention are only examples for clearly explaining the present invention, and are not intended to limit the embodiments of the present invention. For those of ordinary skill in the art, various obvious changes, re-adjustments and substitutions can be made without departing from the protection scope of the present invention. It is not necessary and impossible to enumerate all the embodiments here. Any modifications, equivalent substitutions and improvements made within the spirit and principle of the present invention shall be included in the protection scope of the claims of the present invention.

Claims

1. A photovoltaic junction box, characterized in that: include: Diode (1); terminal(3); A heat sink (2), the heat sink (2) comprising a welding portion (21), the pin of the diode (1) and one end of the terminal (3) being welded to the welding portion (21) by resistance welding, and the pin of the diode (1) being conductively connected to the terminal (3), and the other end of the terminal (3) being used for welding to a busbar (4) by laser welding.

2. The photovoltaic junction box according to claim 1, characterized in that: The welding portion (21) comprises a welding plate, wherein the welding plate, the pin of the diode (1) and the terminal (3) are stacked, and the pin of the diode (1) or the terminal (3) is welded to a surface of one side of the welding plate.

3. The photovoltaic junction box according to claim 2, characterized in that: A plurality of grooves (211) are arranged at intervals on a surface of one side of the welding plate for welding with the pin of the diode (1) or the terminal (3).

4. The photovoltaic junction box according to claim 1, characterized in that: First heat sinks (22) are provided on opposite sides of the welding portion (21), and the first heat sinks (22) extend toward a side away from the welding portion (21) and the pin welding surface of the diode (1).

5. The photovoltaic junction box according to claim 4, characterized in that: The heat sink (2) further comprises a connecting portion (23), one end of the connecting portion (23) being connected to one end of the welding portion (21), second heat sinks (24) being provided on opposite sides of the connecting portion (23), the second heat sinks (24) being arranged at an angle to the connecting portion (23), and the second heat sinks (24) extending in a direction away from the connecting portion (23), the other end of the terminal (3) being disposed between the two second heat sinks (24), and the second heat sink (24) being arranged higher than the other end of the terminal (3).

6. The photovoltaic junction box according to claim 5, characterized in that: The photovoltaic junction box further comprises a base (6), the heat sink (2) is arranged in the base (6), and the connecting portion (23) is in contact with the bottom wall of the base (6); And / or, a projection area of ​​the connecting portion (23) on the bottom wall of the base (6) is greater than a projection area of ​​the welding portion (21) on the bottom wall of the base (6).

7. The photovoltaic junction box according to claim 5, characterized in that: A third heat sink (25) is provided at the other end of the connecting portion (23); the third heat sink (25) is arranged at an angle with the connecting portion (23), and the third heat sink (25) extends in a direction away from the connecting portion (23); the third heat sink (25) is arranged higher than the other end of the terminal (3).

8. The photovoltaic junction box according to claim 1, characterized in that: The terminal (3) comprises a resistance welding connection part (31) and a laser welding connection part (32) connected to the resistance welding connection part (31), the resistance welding connection part (31) is welded to the welding part (21) and is conductively connected to the pin of the diode (1), and the laser welding connection part (32) is used for welding to the busbar (4).

9. The photovoltaic junction box according to claim 8, characterized in that: The terminal (3) further comprises a cable connection portion (33), wherein the cable connection portion (33) is connected to the laser welding connection portion (32), and the cable connection portion (33) is arranged opposite to the resistance welding connection portion (31), and the cable connection portion (33) is conductively connected to a cable (5).

10. The photovoltaic junction box according to claim 8 or 9, characterized in that: The resistance welding connection part (31) comprises a plurality of connection plates (311) arranged at intervals, one end of the connection plate (311) is connected to the laser welding connection part (32), and the connection plate (311) is placed between the welding part (21) and the pin of the diode (1).

11. The photovoltaic junction box according to claim 10, characterized in that: The laser welding connection part (32) is a plate-like structure, one end of the connection plate (311) is bent and connected to one end of the laser welding connection part (32), and one side surface of the laser welding connection part (32) is used to fit and weld with the busbar (4).

12. The photovoltaic junction box according to claim 8 or 9, characterized in that: The resistance welding connection part (31) and the laser welding connection part (32) are both plate-shaped structures; the resistance welding connection part (31) and the laser welding connection part (32) are coplanar; and the pin of the diode (1) is placed between the resistance welding connection part (31) and the welding part (21).

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