CN114101826A

CN114101826A - Brazing filler metal member and brazing method

Info

Publication number: CN114101826A
Application number: CN202110714016.9A
Authority: CN
Inventors: 中原浩昭; 渡边裕彦
Original assignee: Fuji Electric Co Ltd
Current assignee: Fuji Electric Co Ltd
Priority date: 2020-08-28
Filing date: 2021-06-25
Publication date: 2022-03-01
Also published as: JP2022039778A

Abstract

The invention provides a brazing filler metal member which can be stably placed and can make molten brazing filler metal reach narrow parts. The brazing material member (10) includes a linear member (16), a planar mounting surface (20) formed along the longitudinal direction, a first inclined surface (22), and a second inclined surface (24). When viewed from the end face, the extension surface (20a) of the mounting surface (20) and the extension surface (22a) of the first inclined surface (22) form a first acute angle (theta 1), and the extension surface (20a) and the extension surface (24a) of the second inclined surface (24) form a second acute angle (theta 2). The first acute angle (theta 1) and the second acute angle (theta 2) are equal. The linear member (16) includes a hollow portion (16a) along the longitudinal direction. The hollow portion (16a) is filled with flux (18). A plurality of discharge holes (32) are provided in the mounting surface (20) and are aligned in the longitudinal direction and communicate with the hollow section (16 a).

Description

Brazing filler metal member and brazing method

Technical Field

The present invention relates to a brazing filler metal member and a brazing method.

Background

Since the base material is hardly melted at the time of brazing, the dimensional accuracy is high, and since the brazing filler metal reaches the gap of the base material due to wettability, the joining of the portion where the welding rod cannot directly reach can be realized, and the welding rod can be used for various applications.

Brazing is used, for example, to connect a cooling pipe to a bus bar in a distribution board (see patent document 1). In order to solder the cooling pipe to the bus bar, a flux is applied to the contact portion, and further, the operator heats the brazing member while closely adhering the brazing member to the contact portion to melt the brazing member. Brazing is performed from both sides of a portion where the bus bar and the cooling pipe are in contact, and a series of operations requires a certain degree of man-hours. The number of bus bars applied to the inside of the distribution board may be very large, and automation of the brazing work for the cooling pipe is desired.

Documents of the prior art

Patent document

Patent document 1: japanese Kokai publication Sho 58-21908

In order to automatically solder the cooling tube to the bus bar, it is conceivable to dispose a solder member in advance at a soldering site and heat the bus bar, the cooling tube, and the solder member while integrally conveying them.

However, since some vibration occurs during conveyance, the conventional brazing member is displaced by the swinging. Further, the flat bus bar is in contact with the cooling line having a circular cross section, and both sides of the contact portion are very narrow, so that it is difficult to sufficiently reach the melted brazing material member.

Disclosure of Invention

The present invention has been made in view of the above-described problems, and an object thereof is to provide a brazing material member and a brazing method that can be stably placed and can make a molten brazing material reach a narrow portion.

In order to solve the above-described problems and achieve the object, a brazing filler metal member according to the present invention is a wire-shaped brazing filler metal member, comprising: a first surface which is a plane formed along a length direction; and a second surface which is a plane formed along the longitudinal direction or a curved surface which is concave when viewed from the end surface, wherein the first surface and the second surface or their respective extension surfaces form a first acute angle when viewed from the end surface.

May also include: a hollow portion formed along a length direction; the soldering flux is filled in the hollow part; and a plurality of discharge holes formed in at least one of the first surface and the second surface, communicating with the hollow portion, and arranged in a longitudinal direction. The flux after melting can be supplied to the object to be soldered through the discharge hole as described above.

The discharge holes may be formed in a portion other than a range extending at least 10mm from both end surfaces in the longitudinal direction. This can suppress flux from flowing out to a portion other than a desired portion.

The weight ratio of the soldering flux to the whole is 3-5%.

The present invention may further include a third surface that is a flat surface formed along the longitudinal direction or a curved surface that is concave when viewed from the end surface, wherein the first surface and the third surface or their extension surfaces form a second acute angle when viewed from the end surface, and the first acute angle and the second acute angle are equal to each other. This improves the balance.

The first acute angle may be 45 to 75 degrees. This makes it possible to more favorably correspond to the object to be brazed.

Further, a brazing method according to the present invention is a brazing method for brazing an elongated member to a plate material using the brazing material member, comprising: disposing a convex portion of the elongated member, which is convex when viewed from an end surface, in contact with an upper surface of the plate material; disposing the brazing material member so that the first surface abuts against an upper surface of the plate material in a state where the first acute-angled portion is inserted into an acute-angled gap covered with the upper surface of the plate material and the convex portion of the elongated member in the up-down direction; and heating and melting the brazing material member.

The method may further include: the solder member is formed by providing the discharge holes in a linear member made of a solder having the hollow portion filled with the flux, and the solder member is heated and melted within 24 hours after the discharge holes are provided. This prevents deterioration in the quality of the flux.

The brazing material member may be disposed at a contact portion between the plate member and the elongated member from both sides. This improves the strength, thermal conductivity, and balance.

The brazing material member may be heated from a lower surface side through the plate material.

The plate material may be conveyed to a fixed heat source with the long member and the brazing material member placed thereon, and heated by the heat source. Even if a slight vibration is generated by the conveyance, the offset can be suppressed when the first plane of the plane is placed on the upper surface of the plate material.

In the present invention, the first surface of the flat surface is arranged to be in contact with the upper surface of the plate material, thereby stably placing the brazing material member. Further, the molten solder can reach the acute-angle gap as a narrow portion by being disposed so that the first acute-angle portion is inserted into the acute-angle gap.

Drawings

Fig. 1 is a perspective view of a brazing material member according to an embodiment.

Fig. 2 is an end view of the brazing member.

Fig. 3 is a bottom view of the brazing member.

Fig. 4 is a schematic side view of an extruder.

Fig. 5 is a diagram showing a molding process of a first strand blank extrusion-molded by an extruder, in which (a) is a diagram showing an initial stage, (b) is a diagram showing a halfway stage, and (c) is a diagram showing a final stage.

Fig. 6 is a schematic diagram showing a first example of a step of forming a second wire material without a discharge hole from a first wire material.

Fig. 7 is a schematic perspective view showing a second example of the process of forming the second wire material without the discharge hole from the first wire material.

Fig. 8 is a schematic perspective view showing a third example of the process of forming the second wire material without the discharge hole from the first wire material.

Fig. 9 is a view showing a first example of a step of forming a brazing material member by providing discharge holes in the second wire material.

Fig. 10 is a diagram showing a second example of the step of forming the brazing material member by providing the discharge holes in the second wire material.

Fig. 11 is a flowchart of a brazing method according to an embodiment.

Fig. 12 is a partially enlarged view of the solder member, the bus bar, and the cooling pipe in a state of being temporarily assembled as viewed from the end surface direction.

Fig. 13 is a perspective view of the brazing member, the bus bar, and the cooling pipe in a temporarily assembled state.

Fig. 14 is a view showing a brazing process.

Fig. 15 is a perspective view of the bus bar, the cooling pipe, and the brazed portion in a state after brazing.

Fig. 16 is an end view of a brazing member according to a modification, in which (a) is an end view showing the brazing member according to the first modification, (b) is an end view showing the brazing member according to the second modification, (c) is an end view showing the brazing member according to the third modification, (d) is an end view showing the brazing member according to the first modification, and (e) is an end view showing the brazing member according to the fourth modification.

Fig. 17 is a perspective view showing an example in which a brazing material member is applied when the cooling tube of the modification is brazed to the bus bar.

(symbol description)

10. 10A, 10B, 10C, 10D solder member

12 bus bar

12a upper surface

14. 14B cooling pipe

14a lower part (lower convex part)

16 Linear member

16a hollow part

16b end face

18 flux

20 carrying surface

22. 22A first inclined plane

22a, 22Aa, 24a, 24Aa extension surface

24. 24A second inclined plane

26. 28, 30 arc parts

32 discharge hole

40 acute angle clearance

42 assembly

44 brazing part

50 extruder

52a first line blank

52b second wire blank

100 conveying heater

104 heating unit (heating source)

Theta 1 first acute angle

Second acute angle of theta 2

Detailed Description

Hereinafter, embodiments of the brazing material member and the brazing method according to the present invention will be described in detail with reference to the drawings. The present invention is not limited to the embodiments.

Fig. 1 is a perspective view of a brazing filler metal member 10 of an embodiment. Fig. 2 is an end view of the brazing member 10. Fig. 3 is a bottom view of the brazing member 10. The brazing material member 10 is used, for example, to braze the cooling pipe 14 (long member, see fig. 13) to the bus bar 12 (plate material, see fig. 13). The bus bar 12 is a plate material of copper, and is used as an electrical conductor. The cooling pipe 14 is a copper pipe and is a refrigerant flow path for cooling the bus bar 12.

As shown in fig. 1, the brazing member 10 includes a long linear member 16 having a hollow portion 16a and a flux 18 filled in the hollow portion 16 a. The hollow portion 16a is formed along the longitudinal direction of the linear member 16. The filled flux 18 is shown in the figure 1 with dots as evident.

The linear member 16 is a solder material, and is a solder material containing tin, silver, copper, nickel, or the like as a component, for example. The linear member 16 may be brazing filler metal. The flux 18 is, for example, a rosin resin, including organic carboxylic acids, thionic agents, and the like. The weight ratio of the flux 18 to the whole is 3 to 5%. The flux 18 has a lower melting point than the linear member 16 and melts at a stage earlier than the melting of the linear member 16 during brazing.

As shown in fig. 2, the brazing member 10 has a substantially triangular shape on an end surface, and includes a mounting surface (first surface) 20, a first inclined surface (second surface) 22, and a second inclined surface (third surface) 24 formed in the longitudinal direction. The mounting surface 20 is a surface mounted on the upper surface 12a (see fig. 12) of the bus bar 12. In this case, the placement surface 20, the first inclined surface 22, and the second inclined surface 24 are all flat surfaces.

The mounting surface 20 and the first inclined surface 22 are connected by a convex smooth arcuate portion 26. The mounting surface 20 and the second inclined surface 24 are connected by a convex smooth arc portion 28. The first and second

inclined surfaces

22, 24 are connected by a convex smooth circular arc 30. The shape of the arc portion 30 is slightly gentler than the

other arc portions

26, 28, and the total height H of the brazing member 10 is suppressed. The total height H is set to an appropriate value because it is easier to insert the total height H into an acute angle gap 40 (see fig. 12) described later, but if the total height H is too low, a necessary volume cannot be obtained.

When viewed from the end face, the extension surface 20a of the mounting surface 20 and the extension surface 22a of the first inclined surface 22 form a first acute angle θ 1, and the extension surface 20a and the extension surface 24a of the second inclined surface 24 form a second acute angle θ 2. However, the placement surface 20 and the first inclined surface 22 may directly form the first acute angle θ 1 without the arc portion 26, and the placement surface 20 and the second inclined surface 24 may directly form the second acute angle θ 2 without the arc portion 28. The brazing member 10 has a bilaterally symmetric shape when viewed from the end face, and the first acute angle θ 1 and the second acute angle θ 2 are equal.

The mounting surface 20, the first inclined surface 22, and the second inclined surface 24 of the brazing member 10 are preferably surfaces that mutually form an equilateral triangle. That is, θ 1 — θ 2 is preferably 60 degrees. In view of the shape based on the equilateral triangle as described above, it is preferable in terms of stability of placement, strength balance, and ease of manufacture. The first acute angle θ 1 and the second acute angle θ 2 are further described later. The hollow portion 16a has a substantially triangular cross section along the outer shape of the solder member 10.

As shown in fig. 3, a plurality of discharge holes 32 are formed in the mounting surface 20 of the brazing material member 10. The discharge holes 32 are circular holes and are arranged in a line at equal intervals in the longitudinal direction at the center of the mounting surface 20. The discharge hole 32 is a hole perpendicular to the mounting surface 20, and communicates with the hollow portion 16 a. The discharge holes 32 are members for discharging the flux 18 from the hollow portion 16a to the outside at a stage earlier than the melting of the linear member 16 when the brazing material member 10 is used for brazing.

The hole diameter D of the discharge holes 32 is preferably in the range of 30% to 50% with respect to the width D of the brazing material member 10. The reason for this is that when the pore diameter d is too small, the flow of the molten flux 18 may be obstructed. In contrast, in the case of being excessively large, the melted linear member 16 is not uniform in the longitudinal direction, which may cause shape deformation, a volume reduction around the discharge hole 32, a difference in heat capacity per unit length from a portion without the discharge hole 32, and deterioration of uniform wettability at the time of melting, thereby there is a fear that a bonding defect may occur. In the brazing material member 10 of the present embodiment, the width D is 2.6mm, and the hole diameter D is Φ 1.3mm which is 50% of the width D.

The pitch p of the discharge holes 32 is preferably 10mm or less. This is because, if the thickness is 10mm or more, the melted flux 18 cannot be sufficiently supplied to the joint portion of the bus bar 12 and the narrow portion of the cooling pipe 14, and there is a fear that a poor joint may occur.

Further, if the drain hole 32 is set too close to the end surface 16b, the melted flux 18 may flow out to the back surface of the bus bar 12, and the linear member 16 that is successively melted may also flow out to the back surface. The flux 18 and the linear member 16 flowing out to the back surface of the bus bar 12 need to be removed afterwards according to conditions.

In contrast, the discharge holes 32 of the brazing member 10 are formed in the longitudinal direction except for the portions extending by the predetermined length L from the both end surfaces 16b, so that the molten flux 18 discharged from the discharge holes 32 does not flow out to the back surface of the bus bar 12, or the amount of the flux 18 is sufficiently suppressed. This also suppresses the melted linear member 16 from flowing out to the back surface. The predetermined length L is preferably at least 10mm, for example. In addition, it is preferable that the pitch p (see fig. 3) is set to L > p.

The following describes a method for producing the brazing material member 10. The brazing material member 10 is basically manufactured by first manufacturing a first wire material 52a in which the brazing material in a cylindrical shape is filled with the flux 18 (see fig. 5 c), and then manufacturing a second wire material 52b in which the wire diameter of the first wire material 52a is extruded and the cross-sectional shape is triangular (see fig. 6). Finally, the second wire material 52b is formed with the discharge holes 32, thereby obtaining the brazing member 10. The following further describes the details.

Fig. 4 is a schematic side view of extruder 50. Fig. 5 is a diagram showing a molding process of the first string blank 52a extrusion-molded by the extruder 50, in which (a) is a diagram showing an initial stage, (b) is a diagram showing a halfway stage, and (c) is a diagram showing a final stage. Fig. 6 is a schematic diagram showing a first example of a step of forming the second wire material 52b from the first wire material 52a in a state where the discharge hole 32 is not formed. Fig. 7 is a schematic perspective view showing a second example of the step of forming the second wire material 52b without the discharge hole 32 from the first wire material 52 a. Fig. 8 is a schematic perspective view showing a third example of the step of forming the second wire material 52b without the discharge hole 32 from the first wire material 52 a.

As shown in fig. 4, the extruder 50 is a member for extrusion-molding the first string material 52a from the billet (billet)54, and includes a container 56 for accommodating the billet 54, a die 58 provided at the front end of the container 56, a plunger 60 for extruding the billet 54 from the rear of the container 56, and a mandrel 62 disposed in the axial center portion of the whole. Die 58 is held by die ring 58 a. When the billet 54 is pushed out from the rear by the plunger 60, the billet 54 passes through the die head 58 on the front side and is led out to the outside so that the outer periphery thereof becomes circular, but at this time, the mandrel 62 is disposed at the center, so that a circular hollow portion is formed, and the first string material 52a is obtained. The billet 54 may be a cast cylindrical member of 2kg or more, preferably 10kg or more.

In the extrusion molding by the extruder 50, first, as shown in fig. 5 (a), a part of the billet 54 is formed into a plate shape, and the flux 18 is placed on the upper surface thereof. Next, during the course of the extrusion, as shown in fig. 5 (b), the billet 54 is deformed into an arc shape, and gradually surrounds the flux 18. Then, in the final stage, as shown in fig. 5 (c), the first wire material 52a in which the flux 18 is completely surrounded by the material 54 is obtained. Further, although the flux 18 is deteriorated when it contacts air for a long time, the first and

second wire materials

52a and 52b and the brazing material member 10 are covered with the brazing material so that the deterioration of the flux 18 can be prevented. However, it does not matter that the flux 18 contains a small amount of air bubbles in the hollow portion 16a in accordance with the manufacturing condition as long as the flux is not substantially deteriorated.

As shown in fig. 6, in the first example of the step of forming the second wire material 52b from the first wire material 52a, the first wire material 52a fed from the wire feeder 64 passes through the first strainer 66, the extruder 68, and the sintering furnace 70 to form the second wire material 52 b. The second wire blank 52b is further wound at a winder 76 via an exit machine 72 and a second tensioner 74. The wire feeder 64 and the winder 76 are in the form of rolls, for example.

The first strand 52a is extruded by the extruder 68 while changing the diameter and shape of the die, thereby obtaining a predetermined strand diameter and a substantially triangular cross-sectional shape. A predetermined heat treatment is performed in the sintering furnace 70. That is, heating is performed in the case of hot rolling, and cooling (water cooling, oil cooling, etc.) is performed in the case of cold rolling.

As shown in fig. 7, in a second example of the process of forming the second strand 52b from the first strand 52a, a die 78 and a stamp 80 are used. A V-groove 78a is formed in the upper surface of the die 78. The punch 80 is a plate-shaped member that can be lifted and lowered, and is disposed along the V-groove 78a above the die 78. The width of the punch 80 is set to be appropriately smaller than the width of the V-groove 78 a. The first string material 52a is intermittently transferred and disposed in the V-groove 78a, and is pressed by the pressing member 80 from above. Accordingly, the portion pressed by the pressing member 80 forms the mounting surface 20, and the portions pressed by the V-groove 78a form the first inclined surface 22 and the second inclined surface 24. Die 78 and punch 80 as described above are simple structures suitable for small volume production of second strand blank 52 b.

As shown in fig. 8, in a third example of the step of forming the second wire material 52b from the first wire material 52a, a first roller 82 and a second roller 84 are used, which are arranged with their axial centers parallel to each other. The distance between the first roller 82 and the second roller 84 may be adjustable. An annular V-groove 82a is formed in the circumferential surface of the first roller 82. A disk-shaped pressing member 84a is provided on the second roller 84. The pressing member 84a is disposed such that the outer peripheral portion thereof is fitted into the V-groove 82 a. The width of the punch 84a is set to be appropriately smaller than the width of the V-groove 82 a.

The first string material 52a is continuously transferred and passes through the V-groove 82a, and is pressed by the pressing member 84a from above. The first roller 82 and the second roller 84 rotate in opposite directions to introduce and form the first wire blank 52a, which is fed out as the second wire blank 52 b. Other methods of transferring the first string material 52a and the second string material 52b may be used. The portion of the second wire blank 52b pressed by the pressing member 84a forms the mounting surface 20, and the portion pressed by the V-groove 82a forms the first inclined surface 22 and the second inclined surface 24. With the first and

second rollers

82, 84 as described above, continuous operation is possible, suitable for mass production of the second wire blank 52 b.

Next, a process of forming the brazing material member 10 by providing the discharge holes 32 in the second wire material 52b will be described. Fig. 9 is a diagram showing a first example of the step of forming the brazing material member 10 by providing the discharge holes 32 in the second wire material 52 b. Fig. 10 is a diagram showing a second example of the step of forming the brazing member 10 by providing the discharge holes 32 in the second wire material 52 b.

As shown in fig. 9, in the first example of the step of forming the brazing member 10 by providing the discharge holes 32 in the second wire material 52b, the die head 86 and the punch press 88 are used. A V-groove 86a is formed in the upper surface of the die 86. The V-groove 86a having the escape groove 86b formed in the bottom of the V-groove 86a is similar to the V-groove 78a, for example. The punch press 88 is a plate-like member that can be raised and lowered, and is disposed along the V-groove 86a above the die 86. A plurality of punches 88a protruding downward from the lower surface of the punch press 88 are provided along the V-shaped grooves 86 a. The first string material 52a is intermittently transferred and arranged in the V-groove 86a, and is pressed from above by the punch press 88. Then, the plurality of punches 88a come into contact with the mounting surface 20 to punch the same, thereby forming the discharge holes 32. The die 86 and the punch press 88 as described above are simple structures, and are suitable for producing the brazing filler metal member 10 in a small amount. Support dies 90 can also be provided before and after the die 86 as desired. The support die 90 has a V-shaped groove 90a formed therein, so that the first and

second string materials

52a and 52b can be stably supported.

As shown in fig. 10, in the second example of the step of forming the brazing member 10 by providing the discharge holes 32 in the second wire material 52b, the die head 86 and the punch disc 92 are used. Die 86 is the same as the configuration shown in fig. 9. The punch disc 92 may be rotatable, and the distance between the die 86 and the punch disc 92 may be adjustable. A plurality of punches 92a protruding in the radial direction are provided on the circumferential surface of the punch disk 92. The punch 92a is, for example, the same as the punch 88a described above. The lower punch 88a is disposed so that the tip end portion fits into the V-groove 86 a.

The first string material 52a is continuously transferred and passes through the V-groove 86a, and at this time, the punch 92a abuts on the mounting surface 20 from above to punch a hole, thereby forming the discharge hole 32. In this step, the punch disc 92 is rotated to draw in and mold the first string material 52a, and the first string material is sent out as the second string material 52 b. Other methods of transferring the first string material 52a and the second string material 52b may be used. The die 86 and punch press circular plate 92 as described above can be operated continuously, and are suitable for mass production of the brazing member 10.

The V-groove 78a of the die 78, the V-groove 82a of the first roller 82, and the V-groove 86a of the die 86 have substantially the same shape. The V-shaped

grooves

78a, 82a, 86a have a symmetrical shape when viewed from the end face, and are suitable for forming the brazing material member 10 having a symmetrical shape when viewed from the end face. Since the V-

grooves

78a, 82a, and 86a have a symmetrical shape, it is preferable to uniformly disperse the pressing force generated by the punching or boring operation. If the first acute angle θ 1 and the second acute angle θ 2 are θ 1 — θ 2, the brazing filler metal member 10 can be produced by the die 78, the first roller 82, and the die 86 even if the sizes are different.

Next, a brazing method according to an embodiment of the present invention will be described. The brazing method of the present embodiment is a method of brazing the cooling tube 14 to the bus bar 12 using the brazing material member 10. In the brazing method of the present embodiment, another plate material may be used instead of the bus bar 12. Further, other elongate members including a convex portion at the lower side may be used instead of the cooling pipe 14. In fig. 12, a polygonal body 14A is shown by a phantom line as an example of the long member including the convex portion at the lower side as described above. In the above description of the method for manufacturing the brazing member 10, the state in which the discharge holes 32 are not formed is referred to as the second wire material 52b, and the state in which the discharge holes 32 are formed is referred to as the brazing member 10, but hereinafter, both are referred to as the brazing member 10 for convenience.

Fig. 11 is a flowchart of the brazing method according to the present embodiment. Fig. 12 is a partially enlarged view of the brazing member 10, the bus bar 12, and the cooling pipe 14 in a temporarily assembled state as viewed from the end surface direction. Fig. 13 is a perspective view of the brazing member 10, the bus bar 12, and the cooling pipe 14 in a temporarily assembled state. Fig. 14 is a view showing a brazing process. Fig. 15 is a perspective view of the bus bar 12, the cooling tube 14, and the brazed portion 44 in a brazed state.

As shown in fig. 11, in the brazing method according to the embodiment, first, in step S1, the cooling tube 14 is placed in contact with the upper surface 12a of the bus bar 12 (see fig. 12). At this time, the cooling pipe 14 may be temporarily fixed to the bus bar 12 at one or more small points by a fixing method (for example, TIG welding). In step S2, a predetermined length is cut out from the long brazing member 10 wound around the drum or the like. In step S3, the discharge holes 32 are formed in the brazing member 10. In step S4, the brazing material member 10 is placed in a state where the portion at the first acute angle θ 1 is inserted into the acute angle gap 40 covered with the upper surface 12a and the cooling pipe 14 in the upper and lower directions, and the placement surface 20 is brought into contact with the upper surface 12 a. In step S5, the brazing filler metal member 10 is heated by the conveyance heater 100 (see fig. 14). Hereinafter, each step will be described in further detail.

In step S1, the cooling tube 14 is placed in contact with the upper surface 12a of the bus bar 12, and thereby the acute-angle gap 40 is formed, which is covered with the lower portion (lower protruding portion) 14a of the cooling tube 14 and the upper surface 12a of the bus bar 12 in the top-bottom direction when viewed from the end face. The acute angle gap 40 is an acute angle gap, and is not necessarily limited to a gap in which two straight lines form an acute angle, and indicates a region sandwiched by a horizontal plane and an inclined plane or curved surface.

The length of the brazing filler metal member 10 cut out in step S2 is set to a length such that the end surface 16b coincides with the end surface 12b of the bus bar 12, as shown in fig. 13, for example.

The step of forming the discharge hole 32 in step S3 is described with reference to fig. 9 and 10. It is not preferable to leave the brazing member 10 for a long time from the time when the heating process of the brazing member 10 is performed in step S3 to step S5. This is because the flux 18 filled in the hollow portion 16a is exposed to the air when the discharge holes 32 are formed, and the quality deterioration is increased. When the heating and melting process of the brazing member 10 in step S5 is performed within 24 hours after the discharge holes 32 are provided in step S3, the deterioration of the quality of the flux 18 can be reduced.

In step S4, as shown in fig. 12, the brazing material member 10 is placed so that the portion of the first acute angle θ 1 (more specifically, the portion including the arc portion 26 in the region sandwiched between the placement surface 20 and the first inclined surface 22) is inserted into the acute angle gap 40. Thereby, the acute angle gap 40 is sufficiently closed, and the area is narrowed. Further, the brazing member 10 is preferably disposed so that the arc portion 30 or the first slope 22 contacts the cooling pipe 14 at the tangent point C or is sufficiently close to the cooling pipe 14 as close as possible to the contact portion P of the bus bar 12 and the cooling pipe 14. Thereby, the acute-angled gap 40 is further closed and both the brazing member 10 and the cooling pipe 14 are stabilized. However, when it is difficult to bring the brazing material member 10 and the cooling pipe 14 into contact over the entire length thereof due to the dimensional accuracy, shape, and the like of each other, it is needless to say that a part of them may be separated.

Since the solder member 10 is shaped so as to form the first acute angle θ 1 by the mounting surface 20 and the first inclined surface 22, this portion may be slightly pressed into the acute angle gap 40 and slightly inserted therein. This can further stabilize the brazing material member 10.

Since the brazing member 10 has a bilaterally symmetrical shape when viewed from the end face, if the mounting surface 20 is a lower surface when mounted on the upper surface 12a, it may be arranged in the opposite direction to that shown in fig. 12 (with the second inclined surface 24 facing the right side in fig. 12). That is, it is not necessary to particularly distinguish the first and

second slopes

22 and 24. Further, since the discharge holes 32 are formed in the mounting surface 20, the mounting surface can be easily distinguished from other surfaces.

As described above, the brazing material member 10 is disposed so that the mounting surface 20 is in contact with the upper surface 12 a. The mounting surface 20 is a flat surface, and stabilizes the brazing material member 10. Further, as described later, the brazing filler metal member 10 is heated from below via the bus bar 12. Then, the mounting surface 20 of the brazing material member 10 in contact with the upper surface 12a is heated to the hottest and is heated first. Therefore, the lower side of the flux 18 filled in the hollow portion 16a is heated at the beginning and is discharged from an earlier stage to the upper surface 12a through the discharge hole 32. Although the flux 18 is indirectly heated through the constituent members of the bus bar 12 and the mounting surface 20, the flux 18 is reliably discharged from the discharge holes 32 at a stage earlier than the melting of the linear member 16, and predetermined subsequent processing can be performed on the upper surface 12a, because the flux has a lower melting point than the linear member 16 and the discharge holes 32 are formed below.

Depending on the conditions, the discharge hole 32 may be provided on the first slope 22 so as to be directly opened to the acute angle gap 40 as shown by the imaginary line. That is, the discharge hole 32 may be formed in at least one of the mounting surface 20 and the first slope 22.

As shown in fig. 13, in this example, the end surface 14b of the cooling pipe 14 is arranged to coincide with the end surface 12b of the bus bar 12. The cooling pipe 14 is used for supplying a refrigerant from the outside through a joint. The end surface 14b of the cooling pipe 14 may protrude from the end surface 12b of the bus bar 12. On the other hand, the brazing member 10 is disposed so that the end surface 16b coincides with the end surface 12b of the bus bar 12, and the joint length between the cooling pipe 14 and the bus bar 12 is secured as long as possible. This improves the bonding strength and thermal conductivity between the two, and substantially closes the acute angle gap 40 to prevent foreign matter from being caught.

Two brazing members 10 are used, and are disposed in acute angle gaps 40 on both sides of one cooling pipe 14. That is, the brazing member 10 is disposed from both sides with respect to the contact portion P of the bus bar 12 and the cooling pipe 14. In addition, when it is difficult to bring the brazing material member 12 and the cooling pipe 14 into contact over the entire length thereof due to the dimensional accuracy, shape, and the like of each other, it is needless to say that a part of them may be separated. Hereinafter, the bus bar 12, the cooling pipe 14, and the two brazing members 10 temporarily assembled for brazing are referred to as an assembly 42.

As shown in fig. 14, the conveyance heater 100 used in step S5 automatically conveys and heats the packages 42, and this is suitable when the number of packages 42 to be processed is large. The conveyance heater 100 includes a loading unit 102, a heating unit 104, and a unloading unit 106. The loading unit 102 is a member that transports the package 42 to the heating unit 104 by the transport device 108. The conveying device 10 is, for example, a roller or a conveyor. Some preheating device may be provided in the carry-in unit 102. The heating unit 104 is a heating source for heating the assembly 42 from below, and is, for example, an induction heating device or a burner. The heating unit 104 is fixed. The package 42 may be heated while the package 42 is conveyed on the heating unit 104, may be temporarily stopped for heating, or may be decelerated for heating. The carrying-out unit 106 is a member for carrying out the heat-treated package 42, and is, for example, configured similarly to the carrying-in unit 102. Some cooling device may be provided in the carry-out unit 106.

Although the assembly 42 is automatically carried in the carrying heater 100, some vibration may be generated at the time of carrying. However, since the mounting surface 20 of the solder member 10 mounted on the upper surface 12a of the bus bar 12 is a flat surface, it is stably mounted without rolling or shifting in the lateral direction (direction orthogonal to the conveying direction). Therefore, the brazing filler metal member 10 and the brazing method using the brazing filler metal member 10 are suitable for use in equipment including an automatic conveying device in a part using the conveying heater 100 or the like, and for automation of brazing.

Further, even when the package 42 is temporarily stopped or accelerated and decelerated at the position of the heating unit 104, since the placement surface 20 is flat and in contact with the upper surface 12a in a wide area, an appropriate frictional force is ensured, and the package is stably placed without being displaced in the longitudinal direction (conveying direction). In this way, the brazing material member 10 can be heated without being displaced from the upper surface 12a, and the molten brazing material can reach a desired position.

In the heating unit 104, the brazing filler metal member 10 is heated from below via the bus bar 12. The flux 18 filled in the hollow portion 16a is heated from the mounting surface 20. The flux 18 has a melting point lower than that of the linear member 16, and is melted before the linear member 16 is melted, and is discharged from the discharge hole 32. Since the discharge hole 32 is formed in the mounting surface 20 which is the lower surface, it easily flows out to the upper surface 12a of the bus bar 12. The flowing flux 18 removes foreign substances and oxide films on the upper surface 12a and improves wettability. Since the brazing member 10 contains the flux 18 in this way, it is not necessary to perform a separate flux application process.

The flux 18 flowing out of the discharge hole 32 spreads on the upper surface 12a, but may be drawn into the narrow acute-angle gap 40 (see fig. 12) by capillary action and reach the contact point P.

The brazing material member 10 has a shape such that an extended surface 20a of the mounting surface 20 and an extended surface 22a of the first inclined surface 22 form a first acute angle θ 1 when viewed from the end surface. The tip portions of the mounting surface 20 and the first inclined surface 22, that is, portions including the arc portions 26, enter the acute-angle gaps 40 in the narrow portions, and the area of the acute-angle gaps 40 is narrowed. Therefore, the flux 18 flowing out of the discharge hole 32 is easily sucked into the acute angle gap 40 due to the capillary phenomenon.

Similarly, the linear member 16 melted after the flux 18 is melted may have improved wettability due to removal of an oxide film or surface contaminants by the flux 18, and may reach the contact portion P due to a capillary phenomenon caused by the shape of the acute-angled gap 40 in the narrow portion. That is, although it is difficult to directly fill the molten solder into the acute-angled gap 40 in the narrow portion, the portion inserted into the arc portion 26 is further narrowed to generate or enhance the capillary phenomenon, thereby guiding the molten solder. The brazing filler metal members 10 are heated while being provided on both sides of the cooling pipe 14, but it is a matter of course that both the brazing filler metal members 10 are simultaneously heated and melted by the heating means 104 of the conveyance heater 100. Therefore, the process time is greatly shortened as compared with the case where the operator heats the heating plate twice alone.

Fig. 15 is a perspective view of the brazing member 10 of the present embodiment, and the bus bar 12, the cooling pipe 14, and the brazed portion 44 in a state brazed by the brazing method. The cooling pipe 14 is brazed to the bus bar 12 at two locations of the brazing portions 44 on both sides. The brazing portion 44 is a member obtained by melting and then hardening the brazing material member 10. As shown in fig. 15, the brazing portion 44 is filled between the lower portion 14a of the cooling pipe 14 and the upper surface 12a of the bus bar 12 without a gap, in other words, in a portion where the acute-angled gap 40 (see fig. 12) is present without a gap. This is because, as described above, the brazing material member 10 does not undergo positional displacement due to conveyance, and is melted and reaches the contact point P in a state where a part thereof is inserted into the acute angle gap 40. This improves strength and thermal conductivity. Further, two brazed portions 44 are formed by brazing the brazing material member 10 to the cooling pipe 14 from both sides, so that the right-left balance is improved.

The brazed portions 44 are formed substantially uniformly throughout the entire length of the cooling tube 14. This is because the plurality of discharge holes 32 provided in the brazing member 10 are arranged at an appropriate pitch p (see fig. 3), the molten flux 18 is sufficiently spread, and the diameters of the discharge holes 32 are appropriately reduced to make the volume per unit length of the linear member 16 substantially uniform.

The brazing portion 44 is formed to a position substantially coincident with the end surface 12b of the bus bar 12, and hardly reaches the end surface 12b and the back surface. This is because the discharge holes 32 of the brazing member 10 are formed in the portions other than the portions extending at least 10mm from the end surface 16b, and the melted flux 18 hardly leaks out to the end surface 12b of the bus bar 12.

Fig. 16 is an end view showing a modification of the brazing member 10, fig. 16 (a) is an end view of the brazing member 10A of the first modification, fig. 16 (B) is an end view of the brazing member 10B of the second modification, fig. 16 (C) is an end view of the brazing member 10C of the third modification, and fig. 16 (D) is an end view of the brazing member 10D of the fourth modification. In each modification, the same portions as those of the brazing member 10 are denoted by the same reference numerals, and detailed description thereof is omitted.

As shown in fig. 16 (a), in the brazing member 10A of the first modification, the three

arc portions

26, 28, and 30 have the same shape, and the placement surface 20, the first inclined surface 22, and the second inclined surface 24 have the same area. In addition, θ 1 — θ 2 is 60 degrees. Since the brazing material member 10A has no directionality as described above and can have three surfaces as the placement surfaces 20, it is not necessary to distinguish the surfaces in the step of cutting the discharge holes 32 in the step S3.

As shown in fig. 16 (B), in the brazing material member 10B according to the second modification, no flat surface is provided in a portion corresponding to the second slope 24 of the brazing material member 10. Since the first acute angle θ is formed by the mounting surface 20 and the first inclined surface 22 in the brazing filler metal member 10B as described above, when the portion is heated in a state where the portion is inserted into the acute angle gap 40, the melted linear member 16 can be filled in the acute angle gap 40.

As shown in fig. 16 (C), the brazing filler metal member 10C according to the third modification is an example in which the first acute angle θ 1 and the second acute angle θ 2 are not 60 degrees, although θ 1 is equal to θ 2. As described above, the balance is good and preferable when the first acute angle θ 1 and the second acute angle θ 2 are 60 degrees, respectively, but a certain degree of margin is allowed in conformity with the shape of the member to be brazed (the cooling tube 14 in the example of the present invention). That is, it is preferable to set the angle to be appropriately larger than the tangent line of the partner member at the tangent point C (see fig. 12), but it is preferable to set the angle to be in the range of about 60 degrees ± 15 degrees (that is, 45 degrees to 75 degrees) to obtain a certain degree of versatility.

As shown in fig. 16 (D), a brazing member 10D according to a fourth modification example is an example in which a first inclined surface 22A and a second inclined surface 24A having curved surfaces are provided instead of the first inclined surface 22 and the second inclined surface 24 having flat surfaces. The first inclined surface 22A and the second inclined surface 24A are curved surfaces that are concave when viewed from the end surface. The first inclined surface 22A or the second inclined surface 24A having the curved surface as described above is disposed along the circumferential surface of the cylindrical cooling pipe 14, and the

arc portions

26 and 28 can be inserted further into the acute-angled gap 40. In this case, the extension surface 22Aa of the first inclined surface 22A may be defined as a tangent line of the vicinity of the lower end of the first inclined surface 22A. The same applies to the extension surface 24Aa of the second acute angle θ 2.

Fig. 17 is a perspective view showing an example in which the brazing member 10 is applied when the cooling tube 14B of the modification is brazed to the bus bar 12. As in the cooling pipe 14B of fig. 17, the elongated member brazed by the brazing material member 10 may have a curved shape. In this case, the brazing member 10 may be disposed so as to be bent along both sides of the cooling pipe 14B.

The present invention is not limited to the above-described embodiments, and can be freely modified within a scope not departing from the gist of the present invention.

Claims

1. A filler metal member that is a wire-like filler metal member, characterized by comprising:

a first surface which is a plane formed along a length direction; and

a second surface which is a plane formed along the longitudinal direction or a curved surface which is concave when viewed from the end surface,

the first and second faces, or respective elongated faces, form a first acute angle when viewed from the end face.

2. A brazing filler metal component according to claim 1, comprising:

a hollow portion formed along a length direction;

the soldering flux is filled in the hollow part; and

and a plurality of discharge holes formed in at least one of the first surface and the second surface, communicating with the hollow portion, and arranged in a longitudinal direction.

3. A brazing filler metal structure according to claim 2,

the weight ratio of the soldering flux to the whole is 3-5%.

4. A brazing filler metal member according to any one of claims 1 to 3,

and a third surface which is a flat surface formed on the peripheral surface or a curved surface which is concave when viewed from the end surface,

the first surface and the third surface, or the extension surfaces thereof, form a second acute angle when viewed from the end surface,

the first acute angle and the second acute angle are equal.

5. A brazing filler metal member according to any one of claims 1 to 4,

the first acute angle is 45 to 75 degrees.

6. A brazing method for brazing an elongated member to a plate material by using the brazing material member according to claim 2 or claim 3, comprising:

disposing a convex portion of the elongated member, which is convex when viewed from an end surface, in contact with an upper surface of the plate material;

disposing the brazing material member so that the first surface abuts against an upper surface of the plate material in a state where the first acute-angled portion is inserted into an acute-angled gap covered with the upper surface of the plate material and the convex portion of the elongated member in the up-down direction; and

the brazing material member is heated to be melted.

7. The brazing method according to claim 6,

comprises the following steps: the flux is filled in the hollow portion, and the discharge holes are provided in a linear member made of a brazing material, thereby forming the brazing material member.

8. The brazing method according to claim 6 or 7,

the brazing material member is disposed at a contact portion between the plate material and the elongated member from both sides.

9. The brazing method according to any one of claims 6 to 8,

the brazing material member is heated from a lower surface side via the plate material.

10. The brazing method according to any one of claims 6 to 9,

the plate material is transported to a fixed heat source with the long member and the brazing material member placed thereon, and is heated by the heat source.