JP6070792B1 - Evaluation board - Google Patents

Abstract

An evaluation plate capable of accurately evaluating a jet state of molten solder is provided. An evaluation plate 5 includes a flat plate portion 6 having a surface 9 formed flat and having a through hole 11a and a through hole 11b opened on the surface 9, and a groove 12a and a groove 12b opened on the surface 10. . The through hole 11a opens at the bottom surface of the groove 12a. The through hole 11b has the same diameter as the through hole 11a and opens at the bottom surface of the groove 12b. The groove 12a and the groove 12b have a width in the X direction larger than a width in the Y direction orthogonal to the X direction. The distance in the Y direction between the through hole 11a and the through hole 11b is larger than the diameter of the through hole 11a. [Selection] Figure 3

Description

  The present invention relates to an evaluation plate for evaluating a jet state of molten solder.

  Patent Document 1 describes an evaluation plate used when evaluating a jet state of molten solder. The evaluation plate described in Patent Document 1 includes a large number of through holes. The evaluator visually determines how the molten solder enters the through hole formed in the evaluation plate, and determines whether or not the jet state of the molten solder is appropriate.

JP 2014-216390 A

  When using the evaluation plate described in Patent Document 1, the evaluator determines whether or not the molten solder jet state is appropriate based on how the molten solder enters the through hole. The evaluator must confirm the degree of penetration of the molten solder into each through hole in a short time during which the through hole passes over the molten solder. When the molten solder overflows from the through hole, the molten solder collides with the wall surface that forms the dent above the through hole, and the molten solder immediately returns to the through hole. For this reason, there existed a problem that evaluation of a jet state was difficult.

  The present invention has been made to solve the above-described problems. An object of the present invention is to provide an evaluation plate that can accurately evaluate a jet state of molten solder.

In the evaluation plate according to the present invention, the first surface is formed flat, and a first through hole and a second through hole that open on the first surface, and a first groove and a second groove that open on the second surface are formed. And a first guide plate and a second guide plate that are provided on the flat plate portion and have better solder wettability than the flat plate portion . The second surface faces in a direction opposite to the direction in which the first surface faces. The first through hole opens at the bottom surface of the first groove. The second through hole has the same diameter as the first through hole and opens at the bottom surface of the second groove. The first groove and the second groove have a width in the first direction larger than a width in the second direction orthogonal to the first direction. A portion of the edge forming the first through hole that is closest to one end of the first groove in the first direction is formed of the first guide plate. Of the edge that forms the second through hole, the portion of the second groove closest to the one end in the first direction is made of the second guide plate.

The evaluation plate according to the present invention includes a flat plate portion in which the first through hole and the second through hole, the first groove and the second groove are formed, and a first guide plate and a second guide plate provided in the flat plate portion. Is provided. The first through hole opens at the bottom surface of the first groove, and the second through hole opens at the bottom surface of the second groove. The first groove and the second groove have a width in the first direction larger than a width in the second direction orthogonal to the first direction. A portion of the edge forming the first through hole that is closest to one end of the first groove in the first direction is formed of the first guide plate. Of the edge that forms the second through hole, the portion of the second groove closest to the one end in the first direction is made of the second guide plate. With the evaluation plate according to the present invention, it is possible to accurately evaluate the molten solder jet state.

It is sectional drawing which shows the principal part of a jet solder tank. It is sectional drawing which shows the principal part of a jet solder tank. It is a top view which shows the evaluation board in Embodiment 1 of this invention. It is a front view which shows the evaluation board in Embodiment 1 of this invention. It is sectional drawing which shows the principal part of the evaluation board in Embodiment 1 of this invention. It is a figure for demonstrating the formation position of the through-hole with respect to a groove | channel. It is a figure which shows the example by which a to-be-held part is hold | maintained at a conveyor. It is a figure for demonstrating the evaluation method using an evaluation board. It is a figure for demonstrating the evaluation method using an evaluation board. It is a figure for demonstrating the evaluation method using an evaluation board. It is a figure for demonstrating the evaluation method using an evaluation board. It is a figure which shows the state of the molten solder which overflowed from the through-hole. It is a figure which shows the state of the molten solder which overflowed from the through-hole. It is a top view which shows the other example of the evaluation board in Embodiment 1 of this invention. It is a top view which shows the other example of the evaluation board in Embodiment 1 of this invention. It is a top view which shows the evaluation board in Embodiment 2 of this invention. It is a figure which shows the example of arrangement | positioning of a guide plate. It is a figure which shows the example of arrangement | positioning of a guide plate. It is a figure which shows the example of arrangement | positioning of a guide plate. It is a figure which shows the other structural example of a guide plate.

  The present invention will be described with reference to the accompanying drawings. The overlapping description is simplified or omitted as appropriate. In each figure, the same reference numerals indicate the same or corresponding parts.

Embodiment 1 FIG.
First, a jet solder bath will be described with reference to FIGS. FIG.1 and FIG.2 is sectional drawing which shows the principal part of a jet solder tank. The jet solder bath includes a nozzle 1 and a pump (not shown). The pump ejects the molten solder 2 upward from the nozzle 1. The molten solder 2 jetted from the nozzle 1 has a certain range of the liquid surface 2a like a convex mirror surface.

  FIG. 2 shows a state when an electronic component (not shown) is soldered to the printed wiring board 3. The printed wiring board 3 is conveyed by the conveyor 4 so as to cross over the nozzle 1 in a state where electronic components are mounted. When the printed wiring board 3 passes above the nozzle 1, the lower surface of the printed wiring board 3 is immersed in the molten solder 2 jetted from the nozzle 1. When the molten solder 2 attached to the printed wiring board 3 is cooled and solidified, the electronic component is soldered to the printed wiring board 3.

  The state of the molten solder 2 jetted from the nozzle 1 affects the quality of the printed circuit board. By keeping the molten solder 2 jetted from the nozzle 1 constant in an appropriate state, the quality of the printed circuit board can be improved. Hereinafter, an evaluation plate for evaluating the jet state of the molten solder 2 will be described in detail with reference to FIGS.

  FIG. 3 is a plan view showing evaluation plate 5 according to Embodiment 1 of the present invention. FIG. 4 is a front view showing evaluation plate 5 according to Embodiment 1 of the present invention. FIG. 5 is a cross-sectional view showing a main part of evaluation plate 5 in Embodiment 1 of the present invention. FIG. 5 shows an AA cross section of FIG.

  The evaluation plate 5 includes, for example, a flat plate portion 6, a reinforcing portion 7, and a held portion 8. The flat plate part 6 is formed from a plate-shaped member, for example. One surface 9 of the flat plate portion 6 is formed flat. The other surface 10 of the flat plate portion 6 is also formed flat. However, the flatness required for the surface 9 is not required for the surface 10. The surface 10 faces in a direction opposite to the direction in which the surface 9 faces. In the example shown in the present embodiment, the surface 9 of the flat plate portion 6 corresponds to the first surface in the claims. The surface 10 of the flat plate portion 6 corresponds to the second surface in the claims.

  A plurality of through holes 11 and a plurality of grooves 12 are formed in the flat plate portion 6. In the present embodiment, an example in which ten through holes 11 and ten grooves 12 are formed in the flat plate portion 6 is shown. When individually specifying the through holes 11 formed in the flat plate portion 6, they are represented as through holes 11 a to 11 j as shown in FIG. 3. Similarly, when the grooves 12 formed in the flat plate portion 6 are individually specified, they are represented as grooves 12a to 12j as shown in FIG. The number of through holes 11 formed in the flat plate portion 6 is not limited to the example shown in the present embodiment. The number of the grooves 12 formed in the flat plate portion 6 is not limited to the example shown in the present embodiment.

  The through hole 11 opens at the surface 9. For example, the through hole 11 a opens at the surface 9. The through hole 11 b opens at the surface 9. Similarly, the through hole 11 j opens at the surface 9. The through hole 11 opens at the bottom surface of the groove 12. For example, the through hole 11a opens at the bottom surface of the groove 12a. The through hole 11b opens at the bottom surface of the groove 12b. Similarly, the through hole 11j opens at the bottom surface of the groove 12j. It is preferable that a chamfering process is performed on the portion where the through hole 11 opens at the bottom surface of the groove 12 as shown in FIG.

  The shape of the through hole 11 is the same. In the present embodiment, an example in which the through hole 11 is circular is shown. The shape of the through hole 11 is not limited to the example shown in the present embodiment. The through hole 11 may be square. Further, the diameters of the through holes 11 are the same. For example, the diameters of the through holes 11 are all 5 mm. The diameter of the through hole 11 is not limited to the example shown in the present embodiment.

  When the X direction and the Y direction are set as shown in FIG. 3, the through holes 11 a to 11 j are formed so as to be aligned in the Y direction, for example. The X direction and the Y direction are directions parallel to the surface 9 of the flat plate portion 6. The distance in the Y direction between the two through holes 11 is larger than the diameter of the through hole 11. For example, the distance in the Y direction between the through hole 11a and the through hole 11b is larger than the diameter of the through hole 11a. The distance in the Y direction between the through hole 11b and the through hole 11c is larger than the diameter of the through hole 11b. Similarly, the distance in the Y direction between the through hole 11i and the through hole 11j is larger than the diameter of the through hole 11i.

  In the example shown in the present embodiment, one of the through holes 11a to 11j corresponds to the first through hole in the claims. The other one of the through holes 11a to 11j corresponds to the second through hole in the claims.

  The groove 12 opens at the surface 10. The groove 12 has a width W1 in the X direction larger than a width W2 in the Y direction. For example, the width W1 is 100 mm. The width W2 is 10 mm. The width W1 and the width W2 are not limited to the examples shown in this embodiment. However, it is preferable that the widths W2 of the grooves 12 are the same. Further, the depth of the groove 12 is the same. Therefore, the depths of the through holes 11 are the same. The grooves 12a to 12j are formed to be aligned in the Y direction, for example.

  In the example shown in the present embodiment, one of the grooves 12a to 12j corresponds to the first groove in the claims. For example, if the through-hole 11a is a 1st through-hole, the groove | channel 12a which the through-hole 11a opens in a bottom face will become a 1st groove | channel. In the example shown in the present embodiment, another one of the grooves 12a to 12j corresponds to the second groove in the claims. For example, if the through hole 11b is the second through hole, the groove 12b in which the through hole 11b opens at the bottom surface becomes the second groove.

  FIG. 6 is a diagram for explaining a position where the through hole 11 is formed with respect to the groove 12. As shown in FIG. 6, the through hole 11 is formed at a position closer to the other end 13 b than the one end 13 a in the X direction of the groove 12. The distance from the through hole 11 to the one end 13 a of the groove 12 is longer than the distance from the through hole 11 to the other end 13 b of the groove 12. Further, the distance from the through hole 11 to the one end 13a of the groove 12 is larger than the width W2 of the groove 12 in the Y direction. FIG. 6 shows a preferred arrangement in which the through hole 11 is extremely close to the other end 13 b side of the groove 12. The formation position of the through-hole 11 shown in FIG. 6 is an example. The formation position of the through hole 11 with respect to the groove 12 is not limited to the example shown in FIG.

  The reinforcing portion 7 is provided to give the evaluation plate 5 a certain strength. The reinforcing portion 7 is provided on the flat plate portion 6. The reinforcement part 7 is provided in the flat plate part 6 so that it may protrude from the surface 10 of the flat plate part 6, for example. In the example shown in the present embodiment, when the evaluation plate 5 is viewed from the surface 10 side of the flat plate portion 6, the reinforcing portion 7 is disposed so as to surround the periphery of the groove 12.

  The held portion 8 is a portion held by the conveyor 4. The held portion 8 is provided at the edges on both sides of the flat plate portion 6 along the X direction. FIG. 7 is a diagram illustrating an example in which the held portion 8 is held on the conveyor 4. For example, the evaluation plate 5 is held by the conveyor 4 when the held portion 8 is sandwiched between the claws 4 a of the conveyor 4.

  Next, a method for evaluating the jet state of the molten solder 2 using the evaluation plate 5 will be described in detail with reference to FIGS. 8 to 11 are diagrams for explaining an evaluation method using the evaluation plate 5. 8, FIG. 9 and FIG. 11 are views of the jet solder bath as seen from above. FIG. 10 shows a CC cross section of FIG.

  First, as shown in FIG. 1, molten solder 2 is ejected from a nozzle 1. Next, the evaluation plate 5 shown in FIG. 3 is attached to the conveyor 4 as shown in FIGS. And the evaluation board 5 is conveyed by the conveyor 4 so that the upper direction of the nozzle 1 may be crossed similarly to the time of soldering an electronic component to the printed wiring board 3. FIG.

  An arrow B in FIG. 8 indicates a direction in which the evaluation plate 5 is conveyed by the conveyor 4. The X direction shown in FIG. 3 is a direction parallel to the arrow B. The Y direction is a direction orthogonal to the X direction. For example, the evaluation plate 5 is attached to the conveyor 4 such that the groove 12 extends rearward from the through hole 11. In the example shown in the present embodiment, the other end 13b of the groove 12 is arranged in front of the one end 13a with respect to the conveying direction by the conveyor 4.

  When the evaluation plate 5 passes above the nozzle 1, the downward surface 9 of the flat plate portion 6 is immersed in the molten solder 2 jetted from the nozzle 1. 9 and 10 show a state in which a part of the surface 9 of the flat plate portion 6 is immersed in the molten solder 2 jetted from the nozzle 1. Further, when the evaluation plate 5 passes above the nozzle 1, a part of the molten solder 2 jetted from the nozzle 1 enters the through hole 11 from below. The diameter of the through hole 11 and the depth of the groove 12 are set so that the molten solder 2 overflows the through hole 11 when the evaluation plate 5 passes above the nozzle 1 if the jet state of the molten solder 2 is appropriate. Is done.

  12 and 13 are views showing a state of the molten solder 2 overflowing from the through hole 11. FIG. 12 shows an example in which the jet state of the molten solder 2 is appropriate. If the jet state of the molten solder 2 is appropriate, there is no significant difference in the amount of the molten solder 2 overflowing from the through holes 11a to 11j. For example, the difference between the amount of molten solder 2 overflowing from the through hole 11a and the amount of molten solder 2 overflowing from the through hole 11j falls within a certain range. Similarly, the molten solder 2 overflows from the through holes 11a to 11j.

  FIG. 12 shows an example in which the evaluation plate 5 includes a mark 14. For example, the mark 14 is attached in accordance with the position where the tip of the molten solder 2 overflowing from the through hole 11 reaches when the jet state of the molten solder 2 is appropriate. If the evaluation plate 5 includes the mark 14, the position of the tip of the molten solder 2 overflowing from the through hole 11 and the position of the mark 14 can be compared to perform a more accurate evaluation. The evaluation plate 5 may include a mark 14 indicating the range.

  The diameter of the through hole 11 and the width W1 of the groove 12 are set so that the molten solder 2 overflowing from the through hole 11 does not reach the one end 13a of the groove 12 when the jet state of the molten solder 2 is appropriate. It is preferable. The molten solder 2 reaching the one end 13a of the groove 12 hits the wall surface and flows backward. As a result, the flow of the molten solder 2 in the groove 12 is disturbed.

  FIG. 13 shows an example in which the jet state of the molten solder 2 is not appropriate. FIG. 13 shows an example in which the liquid level 2a of the molten solder 2 jetted from the nozzle 1 is inclined. When the liquid level 2a is inclined, there is a difference in the amount of the molten solder 2 overflowing from the through holes 11a to 11j. The evaluator can determine that the jet state of the molten solder 2 is not appropriate based on the amount of the molten solder 2 overflowing from the through holes 11a to 11j.

  By using the evaluation plate 5 having the above configuration, the jet state of the molten solder 2 can be accurately evaluated. For example, the evaluation plate 5 has the through holes 11 and the grooves 12 on the assumption that the molten solder 2 overflows from the through holes 11. Since the groove 12 extends from the through hole 11 to the opposite side in the conveying direction, the molten solder 2 overflowing from the through hole 11 is accumulated in the groove 12 when the evaluation plate 5 passes above the nozzle 1. Further, since the width W1 of the groove 12 is larger than the width W2, it is possible to prevent the molten solder 2 from coming into contact with the wall surface facing the conveyance direction and returning to the through hole 11 immediately after overflowing the through hole 11. The evaluator can appropriately evaluate the jet state of the molten solder 2 by looking at the molten solder 2 accumulated in the groove 12.

  Since the evaluation plate 5 is in direct contact with the high-temperature molten solder 2, it is preferable to have sufficient heat resistance. Thereby, the excessive curvature, twist, and expansion | swelling of the evaluation board 5 can be prevented.

  In the present embodiment, the example in which the jet state of the molten solder 2 is evaluated based on how the molten solder 2 accumulates in the groove 12 has been described. The jet state may be evaluated by weighing the molten solder 2 accumulated in the groove 12.

  The molten solder 2 overflowing from the through hole 11 is gradually cooled and solidified in the groove 12. After the evaluation plate 5 completely passes over the nozzle 1, the evaluation plate 5 is removed from the conveyor 4 and the solidified solder is removed from the groove 12. By measuring the weight of the solder removed from the groove 12, the jet state of the molten solder 2 can be evaluated.

  For example, if the weight of the solder removed from the groove 12 is within the first reference range, it can be determined that the jet state of the molten solder 2 is appropriate. The first reference range is set in advance. For example, if the weight of the solder removed from the groove 12a is within the first reference range, it is determined that the jet state of the molten solder 2 at the position where the through hole 11a is formed is appropriate. Moreover, you may judge whether the jet state of the molten solder 2 is appropriate by comparing the weight of the solder removed from the grooves 12a-12j. For example, if the difference between the heaviest and the lightest of the solders removed from the grooves 12a to 12j is within the second reference range, it can be determined that the jet state of the molten solder 2 is appropriate. The second reference range is set in advance.

  When evaluating the jet state of the molten solder 2 based on the weight of the solder removed from the groove 12, it is not necessary to attach the mark 14 to the flat plate portion 6. Moreover, when evaluating the jet state of the molten solder 2 based on the weight of the solder removed from the groove 12, the through holes 11a to 11j do not have to be aligned in the Y direction. 14 and 15 are plan views showing other examples of the evaluation plate 5 according to Embodiment 1 of the present invention. In the example shown in FIGS. 14 and 15, not all the through holes 11 are aligned in the Y direction. In the example shown in FIG. 14, not all the grooves 12 are aligned. Even if the evaluation plate 5 as shown in FIGS. 14 and 15 is used, the jet state of the molten solder 2 can be appropriately evaluated.

Embodiment 2. FIG.
FIG. 16 is a plan view showing evaluation plate 5 according to Embodiment 2 of the present invention. The evaluation plate 5 further includes, for example, a guide plate 15 in addition to the flat plate portion 6, the reinforcing portion 7 and the held portion 8. The configuration of the reinforcing portion 7 is the same as the configuration disclosed in the first embodiment. The configuration of the held portion 8 is the same as the configuration disclosed in the first embodiment. Of the configurations of the flat plate portion 6, configurations not described in the present embodiment are the same as any of the configurations disclosed in the first embodiment.

  The guide plate 15 is provided so that the molten solder 2 entering the through hole 11 can easily enter the groove 12. For example, when the material of the flat plate portion 6 is resin, a metal plate having better solder wettability than the flat plate portion 6 is employed as the guide plate 15. The guide plate 15 is provided on the flat plate portion 6. In the present embodiment, an example in which the guide plate 15 is arranged corresponding to each of the ten through holes 11 is shown. When the guide plates 15 are specified individually, they are represented as guide plates 15a to 15j as shown in FIG.

  17 to 19 are diagrams showing examples of arrangement of the guide plate 15. 17 and 18 are diagrams corresponding to the DD cross section of FIG. 16. FIG. 17 shows an example in which the guide plate 15 is arranged so that the surface of the guide plate 15 is flush with the surface of the flat plate portion 6 that forms the bottom surface of the groove 12. For example, the surface of the guide plate 15a is flush with the surface of the flat plate portion 6 that forms the bottom surface of the groove 12a. The surface of the guide plate 15b is flush with the surface of the flat plate portion 6 that forms the bottom surface of the groove 12b. Similarly, the surface of the guide plate 15j is flush with the surface of the flat plate portion 6 that forms the bottom surface of the groove 12j. In the arrangement example shown in FIG. 17, it is possible to suppress the occurrence of disturbance in the flow of the molten solder 2 in the groove 12.

  FIG. 18 shows an example in which the guide plate 15 is arranged so that the guide plate 15 protrudes from the surface of the flat plate portion 6 that forms the bottom surface of the groove 12. For example, the guide plate 15a protrudes from the surface of the flat plate portion 6 that forms the bottom surface of the groove 12a. The guide plate 15b protrudes from the surface of the flat plate portion 6 that forms the bottom surface of the groove 12b. Similarly, the guide plate 15j protrudes from the surface of the flat plate portion 6 that forms the bottom surface of the groove 12j. In the arrangement example shown in FIG. 18, the guide plate 15 can be easily attached. When the thin guide plate 15 is adopted, the arrangement example shown in FIG. 18 is preferable.

  As shown in FIG. 19, the guide plate 15 is disposed so as to extend from the through hole 11 toward the one end 13 a of the groove 12. Of the edges forming the through hole 11, the portion E closest to the one end 13 a of the groove 12 is formed of the guide plate 15. For example, a portion E that forms a part of the edge of the through hole 11a is composed of the guide plate 15a. A portion E that forms part of the edge of the through hole 11b is formed of a guide plate 15b. Similarly, a portion E forming a part of the edge of the through hole 11j is composed of a guide plate 15j. The number of guide plates 15 provided in the flat plate portion 6 is not limited to the example shown in the present embodiment.

  With the evaluation plate 5 having the above configuration, the molten solder 2 entering the through hole 11 can be guided to the groove 12 by the guide plate 15. It can suppress that the approach to the groove | channel 12 of the molten solder 2 is inhibited by the surface tension of the molten solder 2.

  In the present embodiment, an example in which the width of the guide plate 15 matches the diameter of the through hole 11 is shown. The configuration of the guide plate 15 is not limited to the above example as long as the molten solder 2 that has entered the through hole 11 can easily enter the groove 12. FIG. 20 is a diagram illustrating another configuration example of the guide plate 15. The width of the guide plate 15 shown in FIG. 20 is smaller than the diameter of the through hole 11. Even if the guide plate 15 shown in FIG. 20 is employed, the same effect as described above can be obtained.

  DESCRIPTION OF SYMBOLS 1 Nozzle, 2 Molten solder, 3 Printed wiring board, 4 Conveyor, 5 Evaluation board, 6 Flat plate part, 7 Reinforcement part, 8 Held part, 9 Surface, 10 Surface, 11 Through-hole, 12 Groove, 13a One end, 13b Other End, 14 mark, 15 guide plate

Claims (6)

An evaluation plate for evaluating a jet state of molten solder,
A flat plate portion in which a first surface is formed flat, and a first through hole and a second through hole opened in the first surface and a first groove and a second groove opened in the second surface ;
A first guide plate and a second guide plate which are provided on the flat plate portion and have better solder wettability than the flat plate portion;
With
The second surface is oriented in a direction opposite to the direction of the first surface;
The first through hole opens at the bottom surface of the first groove,
The second through hole has the same diameter as the first through hole and opens at the bottom surface of the second groove,
The first groove and the second groove have a width in a first direction larger than a width in a second direction orthogonal to the first direction,
Of the edge forming the first through hole, the portion of the first groove closest to the one end in the first direction is composed of the first guide plate,
Of the edge forming the second through hole, the portion closest to the one end of the second groove in the first direction is the evaluation plate made of the second guide plate. The evaluation plate according to claim 1, wherein a distance in the second direction between an end portion of the first through hole and an end portion of the second through hole is larger than a diameter of the first through hole. The evaluation plate according to claim 1 or 2 , wherein the first through hole and the second through hole are formed side by side in the second direction. The first through hole is formed at a position closer to the other end than one end of the first groove in the first direction,
4. The evaluation plate according to claim 1, wherein the second through hole is formed at a position closer to the other end than one end of the second groove in the first direction. 5. The surface of the first guide plate is flush with the surface of the flat plate portion forming the bottom surface of the first groove,
5. The evaluation plate according to claim 1 , wherein a surface of the second guide plate is flush with a surface of the flat plate portion that forms a bottom surface of the second groove. The first guide plate protrudes from the surface of the flat plate portion forming the bottom surface of the first groove,
The evaluation plate according to any one of claims 1 to 4, wherein the second guide plate protrudes from a surface of the flat plate portion that forms a bottom surface of the second groove.

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