JP2006135246A - Terminal box for solar cell module - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent a rectifying function from being damaged thermally. <P>SOLUTION: A plurality of terminal boards 30 are mounted on a substrate 11, and electrically joint between a + electrode and - electrode of a solar cell module and an external connection cable 60 corresponding to both electrodes. A reverse-current bypass diode 50 is bridged between two corresponding terminal boards 30. An adiabatic spacing hole 36 is located on the terminal board 30, and does not disperse a heat from a solder to the surrounding of solder connection portion 90 with the conductive piece 51 of the bypass diode 50. Therefore, the heat from the solder can be collected to the solder connection portion 90. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a terminal box for a solar cell module.

  The solar power generation system supplies a direct current from a solar cell panel laid on the roof of a house to each electrical appliance via an inverter or the like. A solar cell panel consists of a plurality of solar cell modules, and has a structure in which the electrodes of each solar cell module are connected in series or in parallel via a terminal box.

As a conventional terminal box, two terminals are arranged adjacent to each other in the box, and one end is connected to a plus electrode and a minus electrode drawn from the back side of the solar cell module, and the other end is connected to an external connection cable. One provided with two terminal boards and a bypass diode bridged between the two terminal boards is known (for example, see Patent Document 1 below). The bypass diode is for short-circuiting the reverse current at the time of reverse load from one side of the external connection cable to the other, and the chip-like diode function part is sandwiched between the diode function part and the diode function part. It consists of a pair of conductor pieces to be connected. Both conductor pieces have a contact portion with the diode function portion between the overlapping regions, and extend in a direction away from the contact portion, and are soldered to a corresponding terminal plate in the middle of the extension.
Japanese Patent Laid-Open No. 2001-168368 (FIG. 2)

In the above case, when both conductor pieces are soldered to the terminal board, the heat from the solder is released from the terminal board, so the work time required for soldering becomes longer and the rectifying function of the diode function part is thermally damaged. There was concern.
The present invention has been completed based on the above circumstances, and an object thereof is to shorten the soldering operation time and to prevent the rectifying function from being thermally damaged.

  As means for achieving the above object, the invention of claim 1 is a plurality of terminals for electrically relaying between a positive electrode and a negative electrode of a solar cell module and an external connection cable corresponding to both electrodes. In the solar cell module terminal box in which plates are arranged side by side on the substrate and a rectifying device for bypass in reverse load is bridged between two corresponding terminal plates, the rectifying device has a rectifying function. A main body and a pair of conductor pieces that are connected to the rectifying element main body and soldered to the corresponding two terminal plates, respectively, and the terminal plate has a solder connection portion around the conductor piece. It is characterized in that it has a structure in which a thinning part is provided to prevent the heat generated by the solder from escaping.

  According to a second aspect of the present invention, in the first aspect, the thinning portion is disposed between the solder connection portion and the rectifying element main body to insulate the rectifying element main body from heat from the solder. It is characterized by its structure.

  A third aspect of the invention is characterized in that, in the first or second aspect of the invention, the thinned portion is formed by a hollow hole penetrating the terminal plate in the thickness direction.

  According to a fourth aspect of the present invention, in the method according to the third aspect, the lightening hole is formed together with the cut and raised pieces by cutting and raising a part of the terminal plate. It is characterized in that a positioning hole for positioning the rectifying element through the cut and raised piece in the process of placing on the terminal board is provided.

  Invention of Claim 5 is the thing in any one of Claim 1 thru | or 4, The said rectifier element main body is distribute | arranged inside the superposition | polymerization part with which the said pair of conductor piece overlapped in the thickness direction, The overlapping portion is characterized in that it is placed on one of the corresponding two terminal plates.

<Invention of Claim 1>
Since the terminal board is provided with a thinned part around the solder connection part with the conductor piece of the rectifying element so as not to let the heat from the solder escape, the heat from the solder is collected in the solder connection part. The soldering operation time can be shortened and the rectifying element body can be prevented from being thermally damaged.

<Invention of Claim 2>
Since the thinning part is arranged between the solder connection part and the rectifying element main body and has a structure that insulates the rectifying element main body from the heat from the solder, it becomes difficult for the heat from the solder to be transferred to the rectifying element main body side, The temperature rise of the rectifying element body can be suppressed.

<Invention of Claim 3>
Since the thinned portion is made of a hollow hole that penetrates the terminal plate in the thickness direction, it is superior in heat insulating properties as compared with the one formed by removing the terminal plate halfway in the thickness direction.

<Invention of Claim 4>
A lightening hole is formed along with the cut and raised piece of the terminal plate, and the conductor piece is provided with a positioning hole for positioning the rectifying element by inserting the cut and raised piece in the process of mounting on the terminal plate. Therefore, the positioning of the rectifying element can be achieved along with the formation of the heat removal thinning portion, and there is no need to separately provide a positioning means for the rectifying element.

<Invention of Claim 5>
The rectifier element body is arranged between the overlapping portions where the pair of conductor pieces overlap in the thickness direction, and the overlapping portion is placed on one of the corresponding two terminal plates. When the element body generates heat based on its function by energization, the heat can be dissipated from one terminal board, and an excessive temperature rise of the rectifying element body can be more effectively suppressed.

<Embodiment 1>
Embodiment 1 of the present invention will be described with reference to FIGS. The terminal box for a solar cell module according to the present embodiment is attached to the back side of a solar cell module (not shown) in which a large number of solar cells connected in series on the surface are arranged. A large number of terminal plates 30 arranged in the box body 10 and a reverse-flow bypass diode 50 (corresponding to the rectifying element of the present invention) bridged between the adjacent terminal plates 30 are configured.

  The box body 10 is formed of a synthetic resin material in a box shape having an open top surface, filled with an insulating resin, and covered with a cover (not shown) from above. Specifically, as shown in FIG. 1, the box body 10 includes a substantially rectangular substrate 11 on which a plurality of terminal plates 30 are placed side by side, and a side plate 12 that is raised from the peripheral edge of the substrate 11 and surrounds the four sides. And a partition wall 13 that is raised from a predetermined position on the substrate 11 and partitions the adjacent terminal plates 30. A plurality of substantially rectangular openings 14 are formed in the substrate 11, and the end portions of the terminal plates 30 corresponding to the openings 14 face each other. Leads (not shown) connected to both the positive electrode and the negative electrode of the solar cell module are inserted into each opening 14 of the substrate 11, and each inserted lead is soldered to the tip of the terminal plate 30. It is possible to connect.

  On the upper surface of the substrate 11, there is provided a locking projection 19 that can be closely fitted in a locked hole 35 provided in the terminal plate 30. The locking projection 19 is formed in a substantially rectangular shape in plan view. A pair of bendable locking pieces 17 project from two positions on both sides of the substrate 11 with the locking protrusion 19 interposed therebetween. Each locking piece 17 is configured to be vertically raised from the substrate 11 and then folded inward, and the upper surface of the terminal board 30 is pressed against the substrate 11 at the folded end. The locking pieces 17 are elastically expanded and deformed by sliding contact with both side portions of the corresponding terminal plate 30 in the process in which the terminal plate 30 is placed on the substrate 11, and the terminal plate 30 is placed on the substrate 11. Accordingly, the folded end is brought into contact with both side portions of the upper surface of the terminal board 30, and the terminal board 30 is pressed and fixed to the substrate 11 side.

  Further, notches 20 are provided on both side portions on one end side (the lower side shown in FIG. 1) of the side plate 12, and an external output cable 60 is fitted into the cutout 20 from above. The cable 60 is fixed by being fitted. The partition wall 13 is partitioned and formed along the outer edge shape of the terminal plate 30, and an insulating resin such as silicon resin is filled on the terminal plate 30 in the partition wall 13. That is, the partition wall 13 blocks the resin flow of the insulating resin, and contributes to the saving of the insulating resin by not filling the entire box body 10 with the insulating resin.

  The terminal plate 30 is formed in a long strip shape from one end to the other end by a conductive metal plate. Corresponding external connection cables 60 are connected to the terminal boards 30 arranged on both sides of the substrate 11. The core wire 62 is exposed at the end of the cable 60 due to the peeling of the covering 61, and the barrel portion 31 formed at the end of the terminal plate 30 is caulked to the core wire 62, whereby the cable 60 and the terminal plate 30. And are to be connected. A connector portion (not shown) is connected to the end of the cable 60.

Adjacent terminal plates 30 (excluding the terminal plates 30 arranged on both side portions of the substrate 11) are connected together at one end via a connecting portion 32. Of these, one terminal plate 30 does not have a contact point with the solar cell module side, is formed shorter than the other terminal plate 30, and is surrounded by a partition wall 13 around the tip. The heat radiation effect of heat generated by the bypass diode 50 is enhanced by the amount of the one terminal board 30 that is detoured. Attached portions 33 are provided on both side edges of the terminal plate 30 so as to project laterally, and the leading end edges of the attached portions 33 are arranged to face each other between the adjacent terminal plates 30.
In addition, a bypass diode 50 is bridged between adjacent terminal boards 30 so as to cover the attachment portion 33. In the illustrated case, three bypass diodes 50 are arranged in series across the terminal board 30.

  As shown in FIG. 3, the bypass diode 50 is composed of a mesa-type bare chip diode (corresponding to the rectifying device body of the present invention, not shown) and a pair of conductor pieces 51, and the two conductor pieces 51 overlap each other. The bare chip diode is sandwiched inside the portion 55 to be electrically connected to the bare chip diode. The bare chip diode has a structure in which an N-type region (cathode electrode) and a P-type region (anode electrode) are stacked in a trapezoidal shape (Mount Fuji) in order from bottom to top, and a glass film (not shown) is formed around the stacked structure. Z)). An N-side conductor piece 51A is disposed at a position facing the N-type region of both the conductor pieces 51, and a P-side conductor piece 51B is disposed at a position facing the P-type region. In the case of this embodiment, the N-side conductor piece 51A overlaps below the bare chip diode, and the P-side conductor piece 51B overlaps above the bare chip diode.

The N-side conductor piece 51A and the P-side conductor piece 51B extend in a direction away from the overlapping portion 55, and are connected to the corresponding terminal plate 30 by solder welding on the extending end side. The overlapping portion 55 is placed on the attachment portion 33 of the terminal plate 30 to which the N-side conductor piece 51A of the adjacent terminal plates 30 is connected.
As shown in FIG. 3, the N-side conductor piece 51A is thicker than the P-side conductor piece 51B, so that heat dissipation from the N-side conductor piece 51A is efficiently performed. Further, a stress relaxation portion 51E made of two strips is provided in the middle of the extending direction of the P-side conductor piece 51B, and the stress generated during welding to the terminal plate 30 is absorbed by the stress relaxation portion 51E. It is like that.

  The terminal plate 30 is formed with a through hole 36 penetrating from a part of the covering portion of the conductor pieces 51 to the vicinity thereof. Further, the inner side of the hole 36 in the terminal plate 30 is cut by raising the tip side of a portion formed by extending from one side end of the hole edge of the hole 30 to a substantially L shape. A piece 37 is formed. Specifically, the cut-and-raised piece 37 has a substantially square cross-section, and extends in the length direction of the terminal plate 30 from one side end portion on the long side along the arrangement direction of the terminal plates 30 among the hole edges of the lightening holes 36. After that, of the L-shaped pieces extending in the arrangement direction of the terminal plates 30, the portions extending in the arrangement direction of the terminal plates 30 are formed substantially vertically and face each other in parallel between the adjacent terminal plates 30. It is arranged as follows.

  In both conductor pieces 51, a positioning hole 56 is formed so as to penetrate the cut and raised piece 37 and position the bypass diode 50 at a position corresponding to the cut and raised piece 37. The hole edge of the positioning hole 56 is configured to include a portion along the cross-sectional shape of the cut and raised piece 37 so that the solder does not flow out from the positioning hole 56 to the terminal plate 30 side when the solder is applied thereto. is there. The position where the positioning hole 56 is formed is set at both end portions of both conductor pieces 51 apart from the overlapping portion 55 sandwiching the bare chip diode.

  Next, the manufacturing method and effects of this embodiment will be described. First, the terminal board 30 and the cable 60 are caulked and connected by caulking the barrel portion 31 of the terminal board 30 to the core wire 62 exposed at the end of the cable 60. Subsequently, the terminal board 30 is placed on the substrate 11 from above. In the process of placing the terminal plate 30 on the substrate 11, the locking projection 19 on the substrate 11 is fitted into the locked hole 35 of the terminal plate 30 and the locking piece 17 on the substrate 11 is brought into contact with the terminal plate 30. Then, it is elastically expanded and deformed by contact, and after that, the locking projection 19 is closely fitted in the locked hole 35 in a loosely controlled state, and the terminal plate 30 is restricted from being lifted by restoring the locking piece 17. In this state, it is pressed and fixed to the substrate 11 side. And regarding the terminal board 30 distribute | arranged to the both sides of the board | substrate 11, it attaches, covering the cable holding member 65 from the upper part on the cable 60, and fixes the cable 60 on the board | substrate 11. FIG.

  Subsequently, the bypass diode 50 is placed between the adjacent terminal plates 30. At this time, the bypass diode 50 is lowered onto the terminal plate 30 while the cut and raised pieces 37 raised on the terminal plate 30 are passed through the positioning holes 56 of the two conductor pieces 51.

  Next, solder welding is performed on the root portion of the cut and raised piece 37 of the terminal plate 30 to solder-connect the two conductor pieces 51 to the terminal plate 30. Thereby, on the terminal board 30, as shown in FIG.2 and FIG.3, the solder connection part 90 which makes a mountain shape from one surface of the long side of the cut-and-raised piece 37 to the positioning hole 56 is formed. Since the hole 36 of the terminal plate 30 is opened around the solder connection portion 90, that is, directly below and around the conductor piece 51 where the solder connection portion 90 is formed, the solder heat is transferred to the solder connection portion 90. The heat is collected at 90 so as not to escape from the terminal board 30.

  Thereafter, the box body 10 is bonded or fixed to the back surface side of the solar cell module with a bolt. In the process of attachment, the leads connected to both electrodes of the solar cell module are drawn into the box main body 10 through the openings 14 of the substrate 11, and the leads are soldered to the tip of the terminal plate 30. Then, the box body 10 is filled and solidified with an insulating resin such as silicon resin, and the box body 10 is sealed with a cover.

  As described above, according to the present embodiment, the heat insulation holes are formed around the solder connection portions 90 on the terminal board 30 so as to prevent the heat generated by the solder from escaping. Heat is collected in the solder connection portion 90. As a result, the soldering operation time can be shortened and the bare chip diode can be prevented from being thermally damaged.

Further, since the heat due to the solder is not easily transferred to the bare chip diode side by the hollow hole 36, an excessive temperature rise of the bare chip diode can be suppressed and its rectifying function can be maintained.
Further, a lightening hole 36 is formed together with the cut and raised piece 37 by cutting and raising a part of the terminal plate 30, and the cut and raised piece 37 is inserted into one surface of the conductor piece 51 in the process of mounting on the terminal plate 30. Since the positioning hole 56 for positioning the bypass diode 50 is provided, the positioning of the bypass diode 50 can be achieved along with the formation of the heat-insulating thinning hole 36, and a positioning means for the bypass diode 50 is not provided separately. That's it.
Furthermore, since the overlapping portion 55 sandwiched between the bare chip diodes is directly placed on the terminal plate 30 to which the N-side conductor piece 51A is connected, when the bare chip diode generates heat based on its function when energized, The heat can be dissipated from the terminal board 30, and an excessive temperature rise of the bare chip diode can be suppressed more effectively.

<Embodiment 2>
Next, a second embodiment of the present invention will be described with reference to FIG. The second embodiment is substantially the same as the first embodiment except that the bypass diode 50 is packaged by resin sealing and the cut and raised pieces 37 are not provided. Therefore, in FIG. 4, only the main structure around the bypass diode 50 is shown, and the other parts are not shown.

  The bypass diode 50 according to the second embodiment is solder-connected to the square block-shaped resin mold portion 54 that covers the periphery of the bare chip diode and the attachment portion 33 of the corresponding terminal plate 30 that protrudes forward from the front surface of the resin mold portion 54. And a pair of conductor pieces 53 (corresponding to each of P-type (anode side) and N-type (cathode side)). A thin projecting portion 58 is connected to the rear end portion of the resin mold portion 54 through a step 59. A screw member 80 is inserted into the projecting portion 58, whereby the bare chip diode 50 is screwed onto the substrate 11.

On the projecting end side of the attachment portion 33 of the terminal plate 30, a solder connection portion 91 with both conductor pieces 53 is formed. In the attachment portion 33 of the terminal plate 30, a lightening hole 38 is cut out at a position away from the solder connection portion 91 with the conductor piece 53 toward the base end side (left and right direction in FIG. 4) of the attachment portion 33. Is formed. The lightening hole 38 is substantially U-shaped and is open to one side of the attachment portion 33.
According to the second embodiment, the heat from the solder is prevented from escaping from the solder connection portion 91 by the lightening hole 38, so that the soldering operation time can be shortened and the bare chip diode is prevented from being thermally damaged. it can.

<Other embodiments>
The present invention is not limited to the embodiments described with reference to the above description and drawings. For example, the following embodiments are also included in the technical scope of the present invention, and further, within the scope not departing from the gist of the invention other than the following. Various modifications can be made.
(1) In the present invention, it is only necessary to provide a thinned portion for preventing the heat generated by the solder from escaping around the solder connection portion, and the present invention is not necessarily limited to the lightening hole. For example, the thinning portion may be merely thinning the terminal board halfway in the thickness direction.

  (2) In Embodiment 1, in consideration of the positioning of the bypass diode, the cut and raised pieces are erected on the terminal plate side and the positioning hole is provided on the bypass diode side. The cut and raised pieces need not be provided, and the positioning holes need not be provided on the bypass diode side.

The top view which shows the internal composition of the box main body in Embodiment 1 of this invention Side sectional view of the box body Enlarged cross section around bypass diode Enlarged plan view around the bypass diode in Embodiment 2 of the present invention

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Box main body 11 ... Board | substrate 12 ... Side board 30 ... Terminal board 36 ... Meat hole 37 ... Cut-and-raised piece 50 ... Bypass diode (rectifier element)
55 ... Superposition part 60 ... Cable

Claims (5)

A plurality of terminal plates that are electrically connected between the positive and negative electrodes of the solar cell module and the external connection cables corresponding to both electrodes are arranged in parallel on the substrate, and the two corresponding terminal plates are reversed. In the terminal box for the solar cell module in which the rectifying element for bypassing the load is bridged,
The rectifying element includes a rectifying element body having a rectifying function and a pair of conductor pieces connected to the rectifying element body and soldered to the corresponding two terminal plates, respectively.
A terminal box for a solar cell module, wherein the terminal plate is provided with a thinning portion for preventing the heat from the solder from escaping around a solder connection portion with the conductor piece. The said thinning part is arrange | positioned between the said solder connection part and the said rectifier element main body, and has a structure which insulates the said rectifier element main body from the heat | fever by the said solder. Terminal box for solar cell modules. The terminal box for a solar cell module according to claim 1 or 2, wherein the thinning portion is formed by a hole formed through the terminal plate in a thickness direction. The lightening hole is formed together with the cut and raised pieces by cutting and raising a part of the terminal board,
4. The solar cell according to claim 3, wherein the conductor piece is provided with a positioning hole for positioning the rectifying element through the cut and raised piece in the process of mounting on the terminal plate. Module terminal box. The rectifying device main body is arranged inside the overlapping portion where the pair of conductor pieces overlap in the thickness direction, and the overlapping portion is placed on one terminal plate of the corresponding two terminal plates. The terminal box for a solar cell module according to any one of claims 1 to 4, wherein the terminal box is for a solar cell module.

Images