JP2022182184A - Welding structure, and welding method - Google Patents

Abstract

A welded structure and a welding method that achieve both cost reduction and reliability improvement are provided. A welded structure between a lead terminal (2) of an electronic component and a busbar terminal (1) of a busbar, wherein the lead terminal (2) has a bent portion (5) that bends the leading end portion (7) of the lead terminal, and the busbar terminal (1) is a lead terminal. 2, and the weld 1a covers the bent portion 5. As shown in FIG. In the welding method for welding the lead terminal 2 of the electronic component and the busbar terminal 1 of the busbar, the leading end 7 of the lead terminal is bent to form the bent portion 5, which is positioned higher than the leading end 7 of the lead terminal. The front end portion 1a of the busbar terminal 1 is melted and welded so as to cover the bent portion 5. As shown in FIG. [Selection drawing] Fig. 4

Description

The present invention relates to a welded structure and welding method.

As a background art of the present invention, in Patent Document 1 below, lead legs 61 and 62 of a plurality of electrical components are provided in a bus bar fixed to a resin case in order to improve solder connection failure, which is a known problem. and a welding protrusion 21 are welded together to prevent cracks from occurring in the connecting portion.

JP-A-2002-134956

However, in the technique of Patent Document 1, if the amount of oxygen differs depending on the lot of the copper terminal material, voids (blowholes) may be formed at the weld interface under the same conditions, resulting in differences in weldability. . Also, if an attempt is made to connect using oxygen-free copper, which is difficult to stably supply, in order to avoid the generation of voids, there is a problem of increased costs. In view of this, the present invention proposes a welded structure and a welding method that achieve both cost reduction and reliability improvement.

In the welded structure of the lead terminal of the electronic component and the bus bar terminal of the bus bar according to the present invention, the lead terminal has a bent portion that bends the tip of the lead terminal, and the bus bar terminal is welded to the lead terminal. a welded portion overlying the bent portion.
Further, in the welding method of the present invention for welding a lead terminal of an electronic component and a busbar terminal of a busbar, the tip of the lead terminal is bent to form a bent portion, and the bent portion is positioned higher than the tip of the lead terminal. The tip of a certain bus bar terminal is melted and welded so as to cover the bent portion.

According to the present invention, it is possible to provide a welded structure and a welding method that achieve both cost reduction and reliability improvement.

1 is an exploded perspective view of an inverter that employs the welded structure of the present invention; FIG. Capacitor of FIG. FIG. 4 is a diagram showing the positional relationship between busbar terminals and capacitor terminals when they are connected; The figure which shows the welding method of the busbar terminal 1 and the lead terminal 2 based on one Embodiment of this invention. The figure which shows the whole welding chuck part of FIG. The three-dimensional perspective view of FIG. FIG. 3 is a diagram showing parameters of TIG welding comparing the present invention and the conventional invention; A first modification of FIG. A second modification of FIG. 3. The 3rd modification of FIG.

Embodiments of the present invention will be described below with reference to the drawings. The following description and drawings are examples for explaining the present invention, and are appropriately omitted and simplified for clarity of explanation. The present invention can also be implemented in various other forms. Unless otherwise specified, each component may be singular or plural.

The position, size, shape, range, etc. of each component shown in the drawings may not represent the actual position, size, shape, range, etc., in order to facilitate understanding of the invention. As such, the present invention is not necessarily limited to the locations, sizes, shapes, extents, etc., disclosed in the drawings.

(One embodiment and overall configuration of the present invention)
FIG. 1 is an exploded perspective view of an inverter that employs the welded structure of the present invention.

Inverter case 12 accommodates capacitor 8 , substrate 11 having a control circuit, and molded bus bar 10 in addition to a power module (not shown), and is sealed with inverter cover 9 . Capacitor 8 having round-bar terminals (lead terminals 2 to be described later) is assembled to molded bus bar 10 by TIG welding and arranged between inverter case 12 and molded bus bar 10 .

FIG. 2 is a diagram of the capacitor 8 in FIG. 1, and FIG. 3 is a diagram showing the positional relationship when the busbar terminals and the capacitor terminals are connected.

A capacitor 8, which is an electronic component, has lead terminals 2, which are capacitor terminals. A molded busbar 10 has a busbar terminal 1 welded to a terminal 2 .

Regarding the terminals 2, for example, there is a capacitor 8 (see FIG. 2) in which the adjacent lead terminals 2 are close to each other. As a result of welding one of the lead terminals 2 protruding from the two adjacent capacitors 8 to the busbar terminal 1, no change was observed in the other lead terminal 2 which was not welded. For this reason, it is considered that there is no or little influence of interference due to changes in conditions, etc. (see FIGS. 9 and 10) when the lead terminals 2 are joined, which will be described later.

FIG. 4 is a diagram showing a method of welding the busbar terminal 1 and the lead terminal 2 according to one embodiment of the present invention.

TIG welding (arc welding) is performed on the busbar terminal 1 and the lead terminal 2 by a machine (not shown) having an electrode portion 4 and a welding chuck portion 3 . At this time, the lead terminal 2 adjacent to the busbar terminal 1 is formed with a bent portion 5 by bending the tip of the lead terminal 2 . The lead terminal 2 is bent in a direction away from the busbar terminal 1 into a doglegged shape. Also, in order to melt more of the busbar terminal 1 during welding, the busbar welded portion 1a is provided at the tip of the busbar terminal 1 at a position higher than the height of the bent lead terminal 2 . At the time of welding, the busbar welded portion 1a is melted to cover the entire bent portion 5.例文帳に追加As a result, the tip portion of the busbar terminal 1 is melted to form a welded portion, and the busbar terminal 1 and the lead terminal 2 are welded so that the bent portion 5 is entirely covered by the welded portion.

Such a welded structure has the following effects. First, since the lead terminal 2 is welded with the bent portion 5 provided in comparison with the conventional lead terminal, the welded surface is enlarged, so that electrical connection can be established even if a void occurs. The smaller the internal angle of the bent portion 5 (the larger the bent angle), the larger the welding surface, so the welding effect of the present invention becomes more pronounced. Also, the weld of the present invention does not require the use of hard-to-market oxygen-free copper, which is required to avoid voiding. As a result, strong connections can be made even with copper, which contains a large amount of oxygen.

The bent portion 5 of the lead terminal 2 has an allowable angle 5a, and as shown in FIG. 4, if the inner angle of the bent portion is an acute angle or a right angle (in the range of ◯), the effects of the present invention can be realized. If the internal bending angle of the lead terminal 2 is an obtuse angle (in the range of x), the bent portion 5 of the lead terminal 2 will melt completely, resulting in a state in which the welded portion has a large amount of oxygen. is not included in the implementation conditions. For the same reason, the case where the height of the lead terminal 2 is larger than the busbar welded portion 1a is not included in the implementation conditions of the present invention. Moreover, the lead terminal 2 has a length 7 that can be bent until it hits the welding chuck portion 3 .

5 is a view showing the entire welding chuck portion of FIG. 4, and FIG. 6 is a three-dimensional perspective view of FIG.

It is desirable that the electrode part 4 is installed in a state of being floated with respect to the busbar terminal 1 . Moreover, it is desirable that the welding chuck portion 3 is held at a position at a predetermined distance from the tip of the busbar terminal 1 .

FIG. 7 is a diagram showing TIG welding parameters comparing the present invention and the conventional invention.

TIG welding includes preflow, initial energization, upslope, main energization, downslope, and afterflow processes. Of these, conventionally, for the down slope, as shown in the down slope 6, the welding temperature is raised and the down slope time is lengthened in order to remove voids in the state where the bent portion 5 is not present. However, by adopting the present invention, the downslope time can be shortened as shown by the downslope 6a. Therefore, the time until the welding process is completed can be shortened.

8 to 10 are first to third modifications of one embodiment of the present invention, respectively.

As described above, the lead terminal 2 interferes with the welding chuck portion 3 during TIG welding, so from the viewpoint of mass production and tolerance setting, the welding machine at the production site limits the length of the bent portion to 7. There is The length 7a of the bent portion shown in FIG. The length 7b of the bent portion shown in FIG. The length 7c of the bent portion shown in FIG. 10 is perpendicular to the busbar terminal 1, and this is a modification in which the step of bending the lead terminal 2 is the easiest.

According to one embodiment of the present invention described above, the following effects are obtained.

(1) The welded structure between the lead terminal 2 of the electronic component and the busbar terminal 1 of the busbar 10 is such that the lead terminal 2 has a bent portion 5 where the tip of the lead terminal 2 is bent, and the busbar terminal 1 is connected to the lead terminal 2. The welded portion 1a is welded to the , and the welded portion 1a covers the bent portion 5. As shown in FIG. By doing so, it is possible to provide a welded structure that achieves both cost reduction and reliability improvement.

(2) The bent portion 5 of the lead terminal 2 is bent in a direction away from the busbar terminal 1 . By doing so, the welding area is increased.

(3) The lead terminal 2 is bent so that the tip of the lead terminal 2 is parallel to the busbar terminal 1 . By doing so, the welding area is maximized.

(4) The lead terminal 2 is bent so that the tip of the lead terminal 2 is perpendicular to the busbar terminal 1 . By doing so, the bending process can be simplified.

(5) The bent portion 5 of the lead terminal 2 has an acute inner angle. By doing so, the bent portion 5 having the maximum length with respect to the welding chuck portion 3 can be obtained.

(6) The welding method for welding the lead terminal 2 of the electronic component and the busbar terminal 1 of the busbar is to bend the tip of the lead terminal 2 to form the bent portion 5 , which is positioned higher than the tip of the lead terminal 2 . The tip 1a of the busbar terminal 1 is melted and welded so as to cover the bent portion 5. - 特許庁By doing so, it is possible to provide a welding method that achieves both cost reduction and reliability improvement.

The present invention is not limited to the above-described embodiments, and various modifications and other configurations can be combined without departing from the scope of the invention. Moreover, the present invention is not limited to those having all the configurations described in the above embodiments, and includes those having some of the configurations omitted.

1 busbar terminal 1a busbar welded portion (tip of busbar terminal)
2 lead terminal (capacitor terminal)
3 Welding chuck part 4 Electrode part 5 Bending part 5a Allowable angle of bending part 6 Conventional down slope 6a Down slope of the present invention 7, 7a to 7c Tip part of lead terminal 8 Capacitor 9 Inverter cover 10 Molded bus bar 11 Substrate 12 Inverter case

Claims (6)

A welded structure between a lead terminal of an electronic component and a busbar terminal of a busbar,
The lead terminal has a bent portion that bends the tip of the lead terminal,
The busbar terminal has a welded portion welded to the lead terminal,
The welded portion covers the bent portion. The welded structure. A welded structure according to claim 1,
The welded structure is such that the bent portion is bent in a direction away from the busbar terminal. The welded structure according to claim 1 or 2,
The welded structure is such that the lead terminal is bent such that a tip of the lead terminal is parallel to the busbar terminal. The welded structure according to claim 1 or 2,
The welded structure is such that the lead terminal is bent such that a tip of the lead terminal is perpendicular to the busbar terminal. The welded structure according to claim 1 or 2,
The welded structure, wherein the bent portion of the lead terminal has an acute internal angle. A welding method for welding a lead terminal of an electronic component and a busbar terminal of a busbar, comprising:
forming a bent portion by bending the tip of the lead terminal;
A welding method in which the tip of the busbar terminal positioned higher than the tip of the lead terminal is melted and welded so as to cover the bent portion.

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