JP7637907B2 - Solder precoat forming device and mounting board manufacturing device - Google Patents

Description

The present invention relates to a solder precoat forming apparatus and a mounting board manufacturing apparatus.

There is a known electronic component mounting method for manufacturing an electronic component mounting board by mounting electronic components on a board by solder bonding (for example, Patent Document 1). The method of Patent Document 1 includes a step of printing a solder paste and a step of placing electronic components on the solder paste and performing reflow soldering. However, such a method (solder paste printing method) may not be compatible with high-density mounting. For this reason, in recent years, a method of forming a solder coating in advance on the lands of a board on which electronic components are to be placed (solder precoat method) is once again attracting attention (for example, Patent Document 2). The formed solder coating may be called a "solder precoat".

JP 2013-243222 A JP 2018-167297 A

When a manufacturer of electronic component mounted boards wants to manufacture electronic component mounted boards using the solder precoat method, they need to obtain boards that have already been precoated with solder. There are two ways to do this: either procure boards with precoated solder from an outside source, or prepare them in-house. However, procuring them from an outside source increases the manufacturing costs of electronic component mounted boards. It also makes it difficult to quickly respond to design changes to electronic component mounted boards.

On the other hand, if preparing in-house, it is not impossible to use the mounting line that manufactures electronic component mounted boards to form the solder precoat. However, in that case, the settings of the mounting line must be changed depending on whether the solder precoat is formed or the electronic component mounted board is manufactured, which complicates operation and is not practical. Also, because the mounting line is not a facility designed specifically for forming solder precoats, the equipment is expensive and large for its purpose.

In this situation, one of the objects of the present invention is to provide a solder precoat forming device for forming a solder precoat on a substrate. One of the objects of the present invention is to provide a mounted substrate manufacturing device that forms a solder precoat on a substrate and further mounts electronic components on the substrate.

One aspect of the present invention relates to a solder precoat forming device. The device is a solder precoat forming device for forming a solder precoat on a substrate, and includes a solder paste supplying section that supplies solder paste to the substrate in a solder paste supplying area, a heating section including a heating device that heats the solder paste supplied to the substrate to form a solder precoat, a first substrate transporting section that transports the substrate in the solder paste supplying section, a second substrate transporting section that transports the substrate in the heating section, and a control section that controls the first and second substrate transporting sections.

Another aspect of the present invention relates to a mounting board manufacturing apparatus. The mounting board manufacturing apparatus is an apparatus for manufacturing a mounting board including a substrate and electronic components soldered onto the substrate, and includes a solder paste supplying section that supplies solder paste to the substrate in a solder paste supplying area, a first heating section including a heating device that heats the solder paste supplied to the substrate to form a solder precoat, an electronic component mounting device that mounts the electronic components on the solder precoat formed on the substrate, a second heating section that melts the solder precoat on which the electronic components are mounted to solder the electronic components to the substrate, and a substrate transporting device that transports the substrate from the solder paste supplying section to the first heating section, the electronic component mounting device, and the second heating section.

According to the present invention, there is provided a solder precoat forming apparatus for forming a solder precoat on a substrate, and a mounting substrate manufacturing apparatus including a substrate and electronic components soldered onto the substrate.
The novel features of the present invention are set forth in the appended claims, but the present invention, both in terms of structure and content, together with other objects and features of the present invention, will be better understood from the following detailed description taken in conjunction with the drawings.

FIG. 1 is a diagram showing an example of a solder precoat forming apparatus of the present invention. FIG. 2 is a diagram showing a part of an example of a solder precoat forming apparatus of the present invention. FIG. 2 is a diagram showing a part of an example of a solder precoat forming apparatus of the present invention. 2 is a cross-sectional view of an example of a substrate and a mask plate used in the solder precoat forming apparatus of the present invention. FIG. 2 is a cross-sectional view of an example of a substrate and a mask plate used in the solder precoat forming apparatus of the present invention. FIG. 2 is a plan view of an example of a substrate and a mask plate used in the solder precoat forming apparatus of the present invention. FIG. 1 is a diagram showing one step of an example of screen printing using the solder precoat forming apparatus of the present invention. 1 is a diagram showing one step of an example of screen printing using the solder precoat forming apparatus of the present invention. 1 is a cross-sectional view of an example of a substrate on which a solder precoat is formed. FIG. 1 is a diagram showing an example of a mounting substrate manufacturing apparatus according to the present invention. FIG. 1 is a diagram illustrating an example of an electronic component mounting device. 1 is an explanatory diagram of an example of a process for mounting electronic components on a substrate. 1 is an explanatory diagram of an example of a process for mounting electronic components on a substrate. 1 is an explanatory diagram of an example of a process for mounting electronic components on a substrate.

In the following, an example of a solder precoat forming apparatus and an example of a mounting substrate manufacturing apparatus of the present invention will be specifically described with reference to the drawings. Note that all the drawings used in the following description are schematic diagrams.

(Solder precoat forming device)
A solder precoat forming apparatus according to the present invention is an apparatus for forming a solder precoat on a substrate, the apparatus including a solder paste supplying section that supplies solder paste to the substrate in a solder paste supplying area, a heating section including a heating device that heats the solder paste supplied to the substrate to form a solder precoat, a first substrate transporting section that transports the substrate in the solder paste supplying section, a second substrate transporting section that transports the substrate in the heating section, and a control section that controls the first and second substrate transporting sections.

The control unit controls the first and second substrate transport units. There are no particular limitations on the configuration of the control unit, and it is possible to apply a configuration similar to that of a known control unit. For example, the control unit may include a central processing unit (CPU) and a storage device (memory). A program for controlling the first and second substrate transport units may be stored in the storage device.

In the solder precoat forming device, the first and second substrate transport units are controlled by a control unit. Therefore, the solder precoat forming device makes it easy to control substrate transport. In addition, the solder precoat forming device makes it possible to consistently supply solder paste and heat to form a solder precoat in a single device. Therefore, by using the solder precoat forming device in a manufacturing line that manufactures electronic component mounting boards, the configuration of the manufacturing line can be shortened and simplified. In other words, the solder precoat forming device can be preferably used in a manufacturing line that manufactures electronic component mounting boards.

The solder precoat forming apparatus of the present invention may further include a cooling section that cools the substrate transported from the heating section. In this case, the solder precoat forming apparatus may further include a third substrate transport section that transports the substrate in the cooling section, and the control section may control the third substrate transport section.

In the solder precoat forming apparatus of the present invention, the second substrate transport unit may receive and transport the substrate transported from the solder paste supply unit by the first substrate transport unit.

In the solder precoat forming device of the present invention, the solder paste supply unit may supply the solder paste to the substrate by screen printing. In this case, the solder paste supply unit may screen print the solder paste using a mask having an opening larger than the solder precoat to be formed.

Currently, in response to the miniaturization of electronic components, the lands on which the solder precoat is formed are also becoming smaller, and the openings of the masks used in screen printing are also becoming smaller. When using such a mask, in order to properly supply the solder paste, it is necessary to use a solder paste containing fine solder particles. However, solder paste containing fine solder particles is expensive, and this increases the manufacturing costs of electronic component mounting boards. By using a mask with openings larger than the lands on which the solder precoat is formed, it becomes possible to use inexpensive solder paste. In other words, it becomes possible to form the solder precoat inexpensively.

In the solder precoat forming apparatus of the present invention, the heating device may include a local heating device capable of locally heating a portion of the solder paste supplied to the substrate. In this case, the local heating device may perform heating by microwaves or induction heating (heating by electromagnetic induction). The local heating device may perform heating by using hot air, soft beams, infrared rays, radiant heat, etc. Furthermore, when the heating device includes a local heating device, the heating section may include a substrate heating device that heats the entire substrate. By auxiliary heating of the entire substrate with the substrate heating device, it becomes easier to melt the solder with the local heating device.

(Mounting board manufacturing equipment)
The mounting board manufacturing apparatus of the present invention is an apparatus for manufacturing a mounting board including a substrate and electronic components soldered onto the substrate, the apparatus including a solder paste supplying section that supplies solder paste to the substrate in a solder paste supplying area, a first heating section including a heating device that heats the solder paste supplied to the substrate to form a solder precoat, an electronic component mounting device that mounts electronic components on the solder precoat formed on the substrate, a second heating section that melts the solder precoat on which the electronic components are mounted to solder the electronic components to the substrate, and a substrate transporting device that transports the substrate from the solder paste supplying section to the first heating section, the electronic component mounting device, and the second heating section.

The mounting board manufacturing apparatus of the present invention can consistently and efficiently carry out processes from forming a solder precoat on the board to soldering electronic components.

The mounting board manufacturing apparatus of the present invention may further include a cooling section arranged between the first heating section and the electronic component mounting device, and the cooling section may cool the substrate transported from the first heating section.

The mounting board manufacturing apparatus of the present invention may further include a flux application section disposed between the first heating section and the electronic component mounting device, and the flux application section may apply solder flux onto the solder precoat before the electronic components are mounted. In addition, when the mounting board manufacturing apparatus includes the cooling section, the flux application section is disposed between the cooling section and the electronic component mounting device.

The configuration of an example of a solder precoat forming device 10 according to an embodiment of the present invention is shown in Figure 1. In this specification, the direction along which the substrate 1 is transported is referred to as the X-axis, the perpendicular direction is referred to as the Z-axis, and the direction perpendicular to the X-axis and Z-axis is referred to as the Y-axis. The directions along each axis are referred to as the X-direction, Y-direction, and Z-direction, respectively.

The solder precoat forming device 10 is a device that forms a solder precoat portion on a substrate 1. As shown in FIG. 1, the solder precoat forming device 10 includes a solder paste supplying section 100, a heating section 210, and a cooling section 220. These are arranged in a row in the X-axis direction on a base 101. Inside these, a substrate conveying section 230 that conveys the substrate along the X-axis direction is arranged. The solder paste supplying section 100 supplies solder paste to the substrate 1. The heating section 210 heats the solder paste supplied to the substrate 1 to melt the solder particles contained in the solder paste. The cooling section 220 cools and solidifies the melted solder particles (hereinafter sometimes referred to as "molten solder"). The substrate conveying section 230 conveys the substrate 1 in the order of the solder paste supplying section 100, the heating section 210, and the cooling section 220. Inside the base 101, a control section 20 for controlling the solder precoat forming device 10 is arranged. The control unit 20 controls the solder paste supply unit 100, the heating unit 210, the cooling unit 220, and the substrate transport unit 230 to cause the solder precoat forming apparatus 10 to execute the operation of forming a solder precoat on the substrate 1. In this manner, the solder precoat forming apparatus 10 of the present invention is an apparatus that integrally includes the solder paste supply unit 100 and the heating unit 210 necessary for forming the solder precoat.

(Solder paste supply section)
The solder paste supply unit 100 shown in the first embodiment supplies the solder paste onto the substrate 1 by screen printing. As described above, the solder paste may be supplied by a method other than screen printing. For ease of understanding, FIG. 1 shows an example in which the substrate 1 is disposed in each of the solder paste supply unit 100, the heating unit 210, and the cooling unit 220.

The solder paste supply unit 100 includes a movable table 102, a lifting mechanism 103, a printing stage 104, a printing head 113, a camera unit 115, a mask plate (mask) 116, a printing stage conveyor (first board transport unit) 231, a board input conveyor 234, and a board relay conveyor (second board transport unit) 232.

Schematic diagrams of the print stage 104 and the periphery of the print head 113 as viewed from the substrate carry-in conveyor 234 side are shown in Figures 2 and 3. Note that in the following schematic diagrams, illustrations of components that are not necessary for the explanation may be omitted.

A pair of support frames 11 are erected on the base 101 with a gap between them in the X direction. A movable table 102 is arranged on the base 101 sandwiched between the support frames 11. A lifting mechanism 103 that raises and lowers the print stage 104 is arranged on the movable table 102. The movable table 102 moves the lifting mechanism 103 in the horizontal direction (directions along the X-axis and Y-axis, and directions of rotation in a horizontal plane centered on the Z-axis; the same applies below), thereby moving the print stage 104 in the horizontal direction. The lifting mechanism 103 moves the print stage 104 along the Z-axis, i.e., raises and lowers it.

The printing stage 104 includes a base 104a connected to the lifting mechanism 103. A support column 104b is provided on the upper surface of the base 104a. A substrate guide 104c extending along the X-axis is connected to the upper end of the support column 104b. A printing stage conveyor 231 including a belt for transporting the substrate 1 is disposed inside the substrate guide 104c.

The printing stage conveyor 231 is capable of transferring the substrate 1 between the substrate carry-in conveyor 234 arranged to pass through the opening of one of the support frames 11 and the substrate relay conveyor 232 arranged to pass through the opening of the other support frame 11. The substrate 1 carried in by the substrate carry-in conveyor 234 is transferred to the printing stage conveyor 231 and transported to the solder paste supply area PA, where it is held by the printing stage 104. The substrate 1 to which the solder paste has been supplied in the printing stage 104 is transported out of the solder paste supply area PA of the printing stage conveyor 231 and transferred to the substrate relay conveyor 232. In this embodiment, the printing stage conveyor 231 functions as a first substrate transport section that transports the substrate 1 in the solder paste supply section 100 (for example, the solder paste supply area PA). The substrate relay conveyor 232 functions as a second substrate transport section that transports the substrate 1 in the heating section 210. The control unit 20 controls the print stage conveyor 231 (first board transport unit) and the board relay conveyor 232 (second board transport unit).

A backup lifting mechanism 104e is disposed on the upper surface of the base 104a. The backup lifting mechanism 104e raises and lowers a backup section 104f that supports the substrate 1 from below. When the substrate 1 is carried into the solder paste supply area PA of the print stage conveyor 231, the backup section 104f is raised so that the bottom surface of the substrate 1 is supported by the backup section 104f.

A side clamper 104d extending along the X-axis is provided on each of the upper surfaces of the pair of substrate guides 104c. The side clampers 104d are opened and closed by a drive mechanism (not shown). The backup section 104f supports the lower surface of the substrate 1 and at the same time raises the substrate 1 to a height where the upper surface of the substrate 1 and the upper surface of the side clampers 104d are aligned. When the side clampers 104d are closed with the substrate 1 and the side clampers 104d aligned, both side surfaces of the substrate 1 are sandwiched between the side clampers 104d and the substrate 1 is fixed. In this way, the printing stage 104 holds the substrate 1.

A support beam 113a supporting the print head 113 is disposed at the upper end of the pair of support frames 11 so as to be movable in the Y direction via a linear guide mechanism 11a. One end of the support beam 113a is connected to a well-known print head moving mechanism 11b consisting of a feed screw and a motor for rotating the feed screw. When the print head moving mechanism 11b is driven, the print head 113 moves back and forth in the Y direction, which is the squeegeeing direction.

As shown in Figure 2, the print head 113 is provided with a rear squeegee 113b and a front squeegee 113c that extend downward from the support beam 113a. By driving the squeegee drive unit 113d provided on the upper surface of the support beam 113a, either the rear squeegee 113b or the front squeegee 113c is lowered depending on the squeegeeing direction.

A mask plate 116 is disposed horizontally below the print head 113. An opening is formed in the mask plate 116 penetrating in the thickness direction. This opening is an opening (pattern hole) 116a (see FIG. 4A) and is formed to correspond to the arrangement and shape of the lands 1b formed on the substrate 1. The solder paste supply unit 100 performs screen printing to supply the solder paste P onto the substrate 1 in a predetermined printing pattern by moving the solder paste P (see FIG. 3 and FIG. 5A) supplied to the upper surface of the mask plate 116 with either the rear squeegee 113b or the front squeegee 113c.

Now, with reference to Figures 4A to 4C, an example of the substrate 1 on which the solder precoat is formed and the mask plate 116 used in screen printing will be described. Figure 4A is a cross-sectional view of the substrate and mask plate, Figure 4B is a cross-sectional view showing the substrate and mask plate aligned and overlapped, and Figure 4C is a plan view showing the substrate and mask plate aligned and overlapped. Figure 4B is a cross-sectional view taken along line A-A in Figure 4C. As shown in Figure 4A, the substrate 1 includes a plate-shaped portion 1a and a number of lands 1b formed on the plate-shaped portion 1a. The lands 1b are part of the wiring pattern and are the portions on which the solder precoat is formed.

As shown in FIG. 4A, a plurality of openings 116a are formed in the mask plate 116. The positions of the openings 116a correspond to the positions of the lands 1b. However, in the example shown in embodiment 1, the openings 116a are larger than the corresponding lands 1b. In other words, the area of the openings 116a is larger than the area of the corresponding lands 1b. Therefore, when the substrate 1 is perfectly aligned to the mask plate 116 in an ideal state, the lands 1b are located inside the openings 116a.

When the size of land 1b is small, if opening 116a having the same shape (i.e., the same area) as land 1b is used, there may be a case where the solder particles filled in opening 116a by screen printing are insufficient. To avoid this, it is possible to use a solder paste with a very small particle size of solder particles, but in that case, it is necessary to use an expensive solder paste. Therefore, by using opening 116a larger than the area of the corresponding land 1b as in this embodiment, it is possible to solve the problem of solder shortage and the cost problem.

A camera unit 115 is disposed below the mask plate 116. The camera unit 115 can be moved in the X and Y directions by a well-known camera movement mechanism (not shown) fixed to the support frame 11. The camera unit 115 has a built-in camera that photographs the substrate 1 and the mask plate 116 held on the printing stage 104. A substrate reference mark (not shown) for recognizing the position of the substrate 1 is formed on the surface of the substrate 1. Meanwhile, a mask reference mark or hole for the same purpose is formed on the mask plate 116. The control unit 20 photographs the substrate reference mark and the mask reference mark with the camera unit 115 to obtain an image, and performs image recognition of the obtained image to calculate the relative positional deviation between the substrate 1 and the mask plate 116. Then, the moving table 102 is driven to adjust the position of the printing stage 104 so that the positional deviation between the two is zero or minimized, thereby aligning the substrate 1 and the mask plate 116.

(Heating section)
Next, a description will be given of the configuration of the heating unit 210. The heating unit 210 includes a housing 213 that covers the downstream side of the board relay conveyor 232 extending from the solder paste supply unit 100, and a board heating device 211 and a local heating device 212 (heating device) that are arranged inside the housing 213. The housing 213 is formed with an air vent 215 for exhausting volatile components from the solder paste P that are generated by heating.

The local heating device 212 is disposed above the board relay conveyor 232 and can be moved horizontally by a moving mechanism 216 disposed in the housing 213. The local heating device 212 may be any device that locally heats the board 1 or the solder paste P, such as by microwave heating or induction heating. A heating area HA is provided on the board relay conveyor 232, and the local heating device 212 locally heats a portion of the solder paste P of the board 1 located in the heating area HA to melt the solder contained in the portion of the solder paste P. The board heating device 211 is disposed below the board relay conveyor 232 and heats the entire board 1 located in the heating area HA from below. The heating by the board heating device 211 supplementarily heats the board 1 to facilitate the melting of the solder by the local heating device 212. Note that if the solder in the solder paste P can be melted without the board heating device 211, the board heating device 211 may be omitted.

The board relay conveyor 232 receives the board 1 to which the solder paste P has been supplied by the solder paste supply unit 100 and transports it to the heating area HA. Then, when the melting of the solder by the local heating device 212 is completed, the board 1 is transported from the heating area HA to the cooling unit 220 described later. In this embodiment, the board relay conveyor 232 serves as a second board transport unit that transports the board 1 in the heating area HA where heating is performed by the heating device. The board relay conveyor 232 extends from the solder paste supply unit 100 to the heating unit 210 and is shared by both. This allows the board 1 to be transported smoothly from the solder paste supply unit 100 to the heating unit 210, and simplifies and miniaturizes the solder precoat manufacturing device. In this embodiment, the section of the board relay conveyor 232 covered by the housing 213 corresponds to the second board transport unit that transports the board in the heating unit 210. The substrate relay conveyor 232 may be composed of a plurality of substrate transport conveyors separated into a section passing through the heating region HA and other sections. In this case, the substrate transport conveyor in the section passing through the heating region HA corresponds to the second substrate transport section.

(Cooling section)
Next, the configuration of the cooling section 220 will be described. The cooling section 220 includes a housing 224 that covers the board discharge conveyor 233, and a cooling fan (cooling device) 221 arranged inside the housing 224. The housing 224 has vent holes 220a and 220b for introducing and discharging cooling air. The board 1 on the board discharge conveyor 233 is cooled by operating the cooling fan 221. This causes the solder melted in the heating section 210 to be cooled and solidified. In this embodiment, the board discharge conveyor 233 belongs to the board transport conveyor that constitutes the board transport section 230, and corresponds to the third board transport section that transports the board in the cooling section.

The solder precoat forming device 10 of this embodiment is configured as described above. The operation of the solder precoat forming device 10 and the solder precoat forming method will be described below. The control unit 20 operates the board carry-in conveyor 234 and the printing stage conveyor 231 to transport the board 1 on which the solder precoat has not been formed to the solder paste supply area PA. When the board 1 is transported to the solder paste supply area PA, the control unit 20 operates the backup lifting mechanism 104e to have the backup unit 104f support the board 1, and has the side clamper 104d clamp the board. As a result, the printing stage 104 holds the board 1.

Next, the horizontal position of the substrate 1 relative to the mask plate 116 is aligned. To align the substrate 1, first, the substrate reference mark of the substrate 1 held on the printing stage 104 is photographed by the camera unit 115 before the substrate 1 is brought into contact with the mask plate 116. Then, by processing the photographed image, position information regarding the horizontal position of the substrate 1 is obtained (substrate recognition). Note that the position information regarding the horizontal position of the mask plate 116 is previously obtained from the mask reference mark photographed by the camera unit 115 (mask recognition). The control unit 20 calculates the relative positional deviation between the substrate 1 and the mask plate 116 from the positional information regarding the horizontal position of the substrate 1 and the positional information regarding the horizontal position of the mask plate 116, and drives the moving table 102 to adjust the position of the printing stage 104 so that the positional deviation between the two is zero or minimal.

Next, the control unit 20 drives the lifting mechanism 103 to raise the substrate 1 and bring it into contact with the underside of the mask plate 116. Figure 4B shows the state in which the substrate 1 is in contact with the underside of the mask plate 116.

Next, the control unit 20 operates the print head 113 to screen print the solder paste P on the substrate 1. In screen printing, the solder paste P on the upper surface of the mask plate 116 is first moved over the mask plate 116 using the rear squeegee 113b or the front squeegee 113c. As a result, a portion of the solder paste P that has passed through the opening 116a is filled into the opening 116a. FIG. 5A shows the screen printing performed by the rear squeegee 113b. When the rear squeegee 113b moves in the direction of the arrow X1 while in contact with the upper surface of the mask plate 116, the solder paste P on the upper surface of the mask plate 116 is pushed by the rear squeegee 113b and moves over the mask plate 116. Then, when the solder paste P passes through the opening 116a, a portion of it is filled into the opening 116a and supplied to the surface of the land 1b.

Next, the control unit 20 drives the lifting mechanism 103 to separate the substrate 1 from the mask plate 116 (plate separation). FIG. 5B is a cross-sectional view showing the separated substrate 1 and mask plate 116. When the substrate 1 is separated from the mask plate 116, the solder paste P filled in the opening 116a is separated from the mask plate 116 and transferred to the land 1b. The solder paste P transferred to the land 1b is distributed in an island shape on the surface of the substrate 1, but in places where the distance between the lands 1b is small, a connection portion P1 may be formed in which the solder paste P on adjacent lands 1b is connected.

Next, the control unit 20 operates the side clamper 104d and the backup lifting mechanism 104e to release the fixation of the substrate 1 by the side clamper 104d, and lowers the backup unit 104f to place the substrate 1 on the belt of the print stage conveyor 231. Then, the control unit 20 operates the print stage conveyor 231 and the substrate relay conveyor 232 to transport the substrate 1 to the heating area HA in the heating unit 210.

Next, the control unit 20 heats the solder paste P of the substrate 1 located in the heating area HA by the local heating device 212 to melt the solder contained in the solder paste P. The substrate 1 transported to the heating area HA is heated by the substrate heating device 211. This is an auxiliary heating to facilitate the melting of the solder by the local heating device 212. When a predetermined time has elapsed since the heating by the substrate heating device 211, the control unit 20 operates the moving mechanism 216 to sequentially face the local heating device 212 to the solder paste P supplied to the substrate 1. This causes the solder in the solder paste P to melt and spread over the surface of the land 1b. Even if there is a connection portion P1 between adjacent lands 1b, the solder on the land 1b is melted first by the local heating device 212, so that the solder at the connection portion P1 is attracted to the melted solder. Therefore, so-called solder bridges do not occur.

Next, when the control unit 20 has finished melting the solder using the local heating device 212, it operates the board relay conveyor 232 and the board discharge conveyor 233 to transport the board 1 to the cooling unit 220. The cooling unit 220 operates the cooling fan 221 to blow air taken in from the air vents 220a and/or 220b onto the board 1 to cool it. Note that if there is no special need to cool the board 1, cooling by the cooling unit 220 may be omitted.

The cooled substrate 1 is discharged from the cooling section 220 by driving the substrate discharge conveyor 233. In this manner, the solder precoat 2 is formed on the lands 1b on the substrate 1 (Figure 6).

The solder precoat forming device 10 can be used alone, but can also be used in a state where it is incorporated into a mounting substrate manufacturing device. Next, a mounting substrate manufacturing device 400 equipped with the solder precoat forming device 10 will be described with reference to Figures 7 and 8. Note that the solder flux 3 is omitted from Figure 8.

7 is a schematic top view of the configuration of a mounting board manufacturing apparatus 400 according to an embodiment of the present invention. The mounting board manufacturing apparatus 400 includes a loader 80, a solder precoat forming apparatus 10, a solder precoat inspection apparatus 30, a flux application apparatus (flux application section) 40, an electronic component mounting apparatus (electronic component mounting section) 50a, 50b, 50c, a component mounting state inspection apparatus 60, a reflow apparatus (second heating section) 70, and an unloader 90. The solder precoat forming apparatus 10 includes a solder paste supply section 100, a heating section (first heating section) 210, a cooling section 220, and a substrate conveying section 230 that conveys the substrate 1. The substrate conveying section 230 conveys the substrate 1 received from the loader 80 that supplies the substrate 1, in the order of the solder paste supply section 100, the heating section 210, and the cooling section 220. The solder precoat forming apparatus 10 is the same as that described above, so a detailed description thereof will be omitted.

The solder precoat inspection device 30 inspects the shape of the solder precoat 2 (Figure 6) formed on the substrate 1. The solder precoat inspection device 30 measures the shape and volume of the solder precoat 2 using optical measuring devices such as a camera or a three-dimensional measuring machine, and determines whether it meets predetermined standards. The solder precoat inspection device 30 is equipped with a substrate transport conveyor 330 that transports the substrate 1. The substrate transport conveyor 330 receives the substrate 1 on which the solder precoat 2 has been formed from the substrate transport section 230 of the solder precoat inspection device 30, transports it into the device, and then transports the substrate 1 that has completed inspection to a downstream device.

The flux application device 40 applies solder flux 3 (see FIG. 9A) to the solder precoat 2. The flux application device 40 is equipped with application mechanisms such as screen printing, a dispenser, and a sprayer. The flux application device 40 also has a board transport conveyor 340 that transports the board 1. The board transport conveyor 340 transports the board 1 received from the solder precoat inspection device 30 into the device 40 and transports the board 1 coated with flux to a downstream device.

The electronic component mounting devices 50a, 50b, and 50c mount electronic components 4 on the solder precoat 2 covered with solder flux 3. The electronic component mounting devices 50a, 50b, and 50c are equipped with board transport conveyors 350a, 350b, and 350c that transport the board 1. The board transport conveyors 350a, 350b, and 350c transport the board 1 received from the upstream device into each device, and transport the board 1 with the electronic components 4 mounted thereon to the downstream device. Note that the electronic component mounting devices 50b and 50c have the same configuration as the electronic component mounting device 50a, so from here on, only the electronic component mounting device 50a will be described in detail, and the description of the electronic component mounting devices 50b and 50c will be omitted.

8, electronic component mounting device 50a includes a plurality of component supply units 58 arranged on the sides of board transport conveyor 350a, a mounting head 51, and a board support section 55. Board transport conveyor 350a includes a pair of board guides 53L, 53R extending parallel to the X direction, and belt conveyors 54L, 54R provided on opposing surfaces of board guides 53L, 53R.

The belt conveyors 54R and 54L support both ends of the board 1 in the Y direction from below, and are driven by a drive source (not shown) to transport the board 1 in the X direction. The middle part of the board transport conveyor 350a in the X direction is a work area W where electronic components 4 are mounted on the board 1. Below this work area W, a board support part 55 is arranged to support the board 1 from below.

The board support section 55 is provided with a plurality of backup pins 56 that support the underside of the board 1, and a backup pin lifting section 57 that lifts and lowers the backup pins 56. In addition, upper surface pressers 59L, 59R that cover the upper side of the belt conveyors 54L, 54R are attached to the board guides 53L, 53R at the locations corresponding to the work area W. When the backup pin lifting section 57 is driven in a state in which the board 1 is carried into the work area W by the belt conveyors 54R, 54L, the backup pins 56 push up the board 1 and press the upper surfaces of both ends in the Y direction against the upper surface pressers 59L, 59R. As a result, the board 1 is temporarily fixed in the work area W while being sandwiched from above and below by the plurality of backup pins 56 and the pair of upper surface pressers 59L, 59R. The board transport conveyor 350a of the electronic component mounting device 50a carries the board 1 received from the upstream into the work area W in the device, and carries the board 1 after mounting the electronic components 4 to the downstream device.

The electronic component mounting device 50a includes a mounting head 51 and a movement mechanism (not shown) that moves the mounting head 51 in the X and Y directions. The mounting head 51 is equipped with a plurality of suction nozzles 52 that suck and hold the electronic components 4, and further includes a nozzle drive mechanism (not shown) that raises and lowers the suction nozzles 52 and rotates them around the Z axis. The mounting head 51 holds the electronic components 4 supplied by the component supply unit 58 with the suction nozzles 52 and performs the task of mounting the electronic components 4 on a board 1 temporarily fixed in the work area W.

The component mounting state inspection device 60 inspects the mounting state of the electronic components 4 on the board 1. Inspection items include misalignment, poor posture, and the presence or absence of the electronic components 4. The component mounting state inspection device 60 recognizes the mounting state of the electronic components 4, such as the mounting position, posture, and presence or absence, using optical measuring devices such as cameras and three-dimensional measuring machines, and judges whether or not the mounting state satisfies predetermined standards. The component mounting state inspection device 60 is equipped with a board transport conveyor 360 that transports the board 1. The board transport conveyor 360 receives the board 1 on which the electronic components 4 are mounted from the board transport conveyor 350c of the electronic component mounting device 50c, transports it into the device, and transports the board 1 that has completed inspection to a downstream device.

The reflow device 70 includes a plurality of heating devices (not shown) that heat the boards transported by the board transport conveyor 370 that transports the boards 1, and a cooling device (not shown) that cools the heated boards 1. The heating devices heat the boards 1 to a temperature higher than the melting point of the solder, melting the solder precoat. The cooling devices blow cooling air onto the boards 1 to cool the boards 1 and solidify the molten solder precoat. The reflow device 70 solders the electronic components 4 to the boards 1 by transporting the boards 1 from the heating devices to the cooling devices using the board transport conveyor 370. The board transport conveyor 370 transports the boards 1 (electronic component mounted boards) that have been soldered to the unloader 90. The unloader 90 retrieves the boards from the board transport conveyor 370.

1, the mounting board manufacturing apparatus 400 includes a board conveying device 300 including the board conveying section 230 of the solder precoat forming apparatus 10 and board conveying conveyors 330, 340, 350a, 350b, 350c, 360, and 370 provided in each apparatus. The board conveying device 300 conveys the board 1 from the solder paste supply section 100 of the solder precoat forming apparatus 10 to the heating section 210 (first heating section), the component mounting device (50a, 50b, 50c), and the reflow device 70 (second heating section). In this way, by connecting each device from the solder precoat forming apparatus 10 to the reflow device 70, a mounting board manufacturing apparatus 400 can be realized that can continuously perform the process from forming the solder precoat on the board 1 to soldering the electronic component 4 to the board 1.

Next, an example of a method for manufacturing a mounting board in the mounting board manufacturing apparatus 400 will be described below. First, the loader 80 supplies the board 1 to the solder precoat forming apparatus 10. The solder precoat forming apparatus 10 forms a solder precoat 2 on the board 1 received from the loader 80, and transports the board 1 with the solder precoat 2 formed thereon to the solder precoat inspection apparatus 30. Note that the explanation of the method for forming the solder precoat 2 by the solder precoat forming apparatus 10 will be omitted as it overlaps with the content described above.

Next, the solder precoat forming device 10 inspects the solder precoat 2 formed on the board 1, and transports the inspected board 1 to the flux application device 40. As shown in FIG. 9A, the flux application device 40 applies solder flux 3 to cover the solder precoat 2. FIG. 9A shows an example in which the solder flux 3 is applied uniformly on the board 1 to cover multiple solder precoats 2. However, the solder flux 3 may be applied in dots corresponding to each solder precoat 2. The solder precoat forming device 10 transports the board 1 to which the solder flux 3 has been applied to the electronic component mounting device 50a.

Next, the electronic component mounting device 50a mounts the electronic component 4 on the board 1 to which the solder flux 3 has been applied. In the example shown in FIG. 9B, the electronic component 4 includes two terminal portions 4a and an element portion 4b. The electronic component mounting device 50a aligns the terminal portion 4a with the solder precoat 2 and places the electronic component 4 on the solder precoat 2 to which the solder flux 3 has been applied. The mounting work of the electronic component 4 is performed on the board 1 that has been carried into the work area W by the board transport conveyor 350a and temporarily fixed by the board support portion 55 in the work area W. The mounting head 51 holds the electronic component 4 supplied from the component supply unit 58 with the suction nozzle 52 and mounts it on the board 1 in the work area W (FIG. 8). The mounted electronic component 4 is temporarily fixed to the board 1 by the adhesive solder flux 3. This prevents the board 1 from being displaced from the solder precoat 2 due to vibration caused by transport. The electronic component mounting device 50a conveys the board 1 on which the electronic components have been mounted to the downstream electronic component mounting device 50b, where the electronic components are similarly mounted.

Next, the component mounting state inspection device 60 inspects the mounting state of the electronic components 4 mounted on the board 1 that has been removed from the electronic component mounting device 50c. After completing the inspection, the board is removed to the downstream reflow device 70.

Next, the reflow device 70 heats the board 1 to solder the electronic components 4. The reflow device 70 heats the board 1, which is being transported by the board transport conveyor 370, with heating devices arranged above and below the board transport conveyor 370, to melt the solder precoat 2 on the board 1 on which the multiple electronic components 4 are arranged. The board 1 is then cooled with a cooling device arranged at the end of the board transport conveyor 370 to solidify the molten solder precoat. This electrically connects the electronic components 4 to the lands 1b via the solder joints 5 (solder precoat that has solidified after melting). In other words, the electronic components 4 are mounted on the board 1. In this manner, the electronic component mounting board 1x is manufactured.

This is the above embodiment of the present invention, but modifications may be made without departing from the scope of the present invention. The solder paste supply unit may be anything other than screen printing as long as it can supply solder paste to a specified area of the board, and may be configured as an applicator such as a dispenser. However, in consideration of cost and productivity, the present embodiment employing screen printing is preferable. Also, the heating device does not need to be a localized heater. It may be one that heats the entire board, or one that heats the board by placing it on a hot plate.

The present invention can be used in a solder precoat forming apparatus and a mounting board manufacturing apparatus.
Although the present invention has been described with respect to the presently preferred embodiments, such disclosure should not be interpreted as limiting. Various variations and modifications will no doubt become apparent to those skilled in the art to which the present invention pertains upon reading the above disclosure. Accordingly, the appended claims should be interpreted to cover all variations and modifications without departing from the true spirit and scope of the present invention.

1: Substrate 2: Solder precoat 5: Solder bonding section 10: Solder precoat forming device 20: Control section 50a, 50b, 50c: Electronic component mounting device 100: Solder paste supply section 210: Heating section 211: Substrate heating device 212: Local heating device 220: Cooling section 230: Substrate transport section 231: Printing stage conveyor (first substrate transport section)
232: Board relay conveyor (second board transport unit)
233: Substrate unloading conveyor (third substrate transport unit)
234: Substrate carry-in conveyor 300: Substrate transport device 400: Mounting substrate manufacturing device HA: Heating area P: Solder paste PA: Solder paste supply area

Claims (9)

A solder precoat forming apparatus for forming a solder precoat on a substrate, comprising:
a solder paste supply unit that supplies solder paste to the substrate in a solder paste supply area;
A heating unit including a heating device that heats the solder paste supplied to the substrate to form a solder precoat;
a first substrate transport unit that transports the substrate in the solder paste supply unit;
a second substrate transport unit that transports the substrate in the heating unit;
A control unit that controls the first and second substrate transport units;
Equipped with
the heating device includes a local heating device capable of locally heating a portion of the solder paste supplied to the substrate,
The heating section includes a substrate heating device that heats the entire substrate . The solder precoat forming device according to claim 1, further comprising a cooling section for cooling the substrate transported from the heating section. a third substrate transport unit configured to transport the substrate in the cooling unit;
The solder precoat forming apparatus according to claim 2 , wherein the control unit controls the third substrate transport unit. The solder precoat forming device according to any one of claims 1 to 3, wherein the second substrate transport unit receives and transports the substrate transported from the solder paste supply unit by the first substrate transport unit. The solder precoat forming device according to any one of claims 1 to 4, wherein the solder paste supply unit supplies the solder paste to the substrate by screen printing. The solder precoat forming device according to any one of claims 1 to 5, wherein the local heating device performs heating by microwaves or induction heating. 1. A mounting board manufacturing apparatus for manufacturing a mounting board including a substrate and electronic components soldered onto the substrate, comprising:
a solder paste supply unit that supplies solder paste to the substrate in a solder paste supply area;
a first heating unit including a heating device that heats the solder paste supplied to the substrate to form a solder precoat;
an electronic component mounting device that mounts the electronic components on the solder precoat formed on the substrate;
a second heating section that melts the solder precoat on which the electronic component is mounted to solder the electronic component to the substrate;
a substrate conveying device that conveys the substrate from the solder paste supplying unit to the first heating unit, the electronic component mounting device, and the second heating unit;
Equipped with
the heating device includes a local heating device capable of locally heating a portion of the solder paste supplied to the substrate,
The first heating section includes a substrate heating device that heats the entire substrate . Further comprising a cooling unit disposed between the first heating unit and the electronic component mounting device,
The mounting substrate manufacturing apparatus according to claim 7 , wherein the cooling section cools the substrate transferred from the first heating section. The electronic component mounting device further includes a flux coating unit disposed between the first heating unit and the electronic component mounting device,
9. The mounting board manufacturing apparatus according to claim 7 , wherein the flux applying section applies solder flux onto the solder precoat before the electronic components are mounted.

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