CN102164473A - Element mounting device and element mounting method - Google Patents

Abstract

The invention provides an element mounting device and an element mounting method. The element mounting device comprises a head assembly and a control part. Elements are installed on a substrate by the head assembly. The motion of the head assembly is controlled by the control part. Meanwhile, the mounting position of elements is adjusted according to the printing offset of the solder with respect to the electrode. When the printing offset is within a correction permissible range, the elements are installed on the substrate with the offset position of the solder on the substrate as a reference. The correction permissible range is set according to the self-correction effect exhibited by the fused solder, so that the mounting position of the elements is corrected to be at the electrode side. When the printing offset exceeds the correction permissible range, the elements are installed with the specified position close to the electrode as a reference within the offset range of the solder on the substrate. Therefore, the mounting position of the elements is adjusted according to the offset, so that the bad welding is prevented and the elements are satisfactorily installed on the substrate.

Description

Component mounting device and component mounting method

Technical Field

The present invention relates to a component mounting apparatus and a component mounting method for mounting a component on a substrate having electrodes printed with solder.

Background

In order to manufacture a substrate on which electronic components are mounted (hereinafter referred to as "component mounting substrate"), the following processes are sequentially performed: a printing step of printing solder on so-called substrate electrodes (or pads), which are electrodes formed on a substrate, by a printing apparatus; mounting a component on the substrate printed with the solder by using a component mounting apparatus; and a reflow step of passing the substrate mounted with the component through a reflow furnace. In the printing step among these steps, the solder paste is printed on the surface of the substrate through the openings of the stencil while the stencil having the openings corresponding to the substrate electrode patterns is accurately aligned with the substrate. In this way, in the printing step, the alignment of the stencil and the substrate is performed, and the positional displacement of the solder with respect to the substrate electrode, that is, the printing displacement amount is set to zero. However, it is very difficult to set the printing offset to zero in an actual printing process.

In the reflow step, the solder between the substrate electrodes of the substrate and so-called element electrodes such as electrodes and leads formed on the case of the electronic element is melted and flows. At this time, the mounting position of the electronic component is corrected by a so-called self-correcting effect in which the electronic component moves toward the center position side of the substrate electrode based on the solder flow. Therefore, for example, in the invention disclosed in japanese patent laid-open publication No. 2007-110170 (patent document 1) (see fig. 20 and 21), the magnitude of the self-correcting effect is determined based on the print offset state, and the mounting position of the electronic component is switched based on the determination result. More specifically, when the self-correcting effect is large, the electronic component is mounted with reference to the solder printing position, and when the self-correcting effect is small, the electronic component is mounted with reference to the electrode position of the substrate.

In the invention disclosed in patent document 1, when the self-correcting effect is small, for example, when solder is printed in a state of being greatly deviated from an electrode formed on a substrate, it is determined that the self-correcting effect is small, and an electronic component is mounted with the electrode position of the substrate as a reference. Therefore, as described later, the solder that has deviated from the electrode melts and adheres to the end surface of the electronic component by the reflow process, and further largely wets along the end surface, thereby causing a poor soldering.

Disclosure of Invention

The present invention has been made in view of the above problems, and an object of the present invention is to provide a component mounting apparatus and a component mounting method capable of preventing occurrence of soldering failure and satisfactorily mounting a component on a substrate by appropriately adjusting a mounting position of the component in accordance with a print offset amount.

In order to achieve the above object, a component mounting apparatus according to the present invention is a device for mounting a component on a substrate on which electrodes are formed and solder is printed on the electrodes, the device including: a head assembly mounting the component to the substrate; a control unit for controlling the operation of the head unit and adjusting the mounting position of the component according to the printing offset of the solder with respect to the electrode; wherein the control portion mounts the component with reference to a position of the solder deviated on the substrate as a deviation allowing range in which a mounting position of the component can be corrected to a correction allowing range on the electrode side by a self-correcting effect exhibited based on melting of the solder when the amount of the printing deviation is within the correction allowing range, and mounts the component with reference to a specified position which is closer to the electrode and the correction allowing range in the range of the solder deviated on the substrate (more strictly, a specified position which is closer to the electrode than a printing position of the solder and is apart from the position of the electrode within the correction allowing range to a position side on the substrate on which the solder is printed) when the amount of the printing deviation is out of the correction allowing range.

In order to achieve the above object, a component mounting method according to the present invention is a method for mounting a component on a substrate on which electrodes are formed and solder is printed on the electrodes, the method including the steps of: determining a printing offset amount of the solder with respect to the electrode; a step of comparing the printing offset amount with a correction allowable range that is a correction allowable range in which the mounting position of the component can be corrected to the electrode side by a self-correcting effect exhibited based on melting of the solder; and mounting the component with reference to a position of the solder deviated from the substrate as a reference when the print deviation amount is within the correction allowance range, and mounting the component with reference to a position of the solder deviated from the substrate by the electrode in a range of the solder deviated from the substrate as a reference when the print deviation amount is beyond the correction allowance range.

In the present invention (component mounting apparatus and component mounting method) configured as described above, the position of the mounted component is adjusted in accordance with the amount of print offset of the solder with respect to the electrode formed on the substrate. More specifically, in the case where the amount of print deviation is within a correction allowable range in which the mounting position of the component can be corrected to the electrode side by the self-correcting effect, the component is mounted with reference to the position where the solder is deviated on the substrate. By utilizing the self-alignment effect in this manner, the element can be mounted on the substrate satisfactorily. On the other hand, when the amount of print deviation exceeds the correction allowable range, that is, when the correction effect cannot be expected, the component is mounted with reference to a predetermined position in the correction allowable range out of the range in which the solder is deviated on the substrate. Thus, by reducing the amount of solder spreading by wetting to the adjacent electrodes on the substrate during the reflow process, it is possible to prevent the occurrence of defective soldering and to mount the component at the correct position with respect to the position of the electrode on the substrate. The present invention will be described in detail with reference to specific examples.

As described above, since the positional reference for mounting the component is adjusted depending on whether or not the amount of printing shift of the solder with respect to the electrode is within the correction allowable range in which the mounting position of the component can be corrected to the electrode side by the self-correcting effect, the occurrence of the soldering failure can be prevented, and the component can be mounted at the correct position with respect to the position of the electrode of the substrate.

Drawings

Fig. 1 is a block diagram showing a production system of a component-mounted substrate in which a component is mounted on a substrate.

Fig. 2 is a schematic diagram showing a relationship between a positioning form in the component mounting process and a solder state after the reflow process when a relatively large print misalignment occurs.

Fig. 3 is a schematic diagram showing an example of an element ((a) of fig. 3) and a graph showing information on the element ((B) of fig. 3).

Fig. 4 is a schematic view showing a component mounting form according to a printing offset amount.

Fig. 5 is a plan view showing an embodiment of a mounting machine (component mounting apparatus) according to the present invention.

Fig. 6 is a block diagram showing a main electrical configuration of the mounting machine shown in fig. 5.

Fig. 7 is an ER diagram showing an example of the configuration of the mounter-related control parameters shown in fig. 5.

Fig. 8 is a flowchart showing a setting process executed by the printing apparatus before the component mounting substrate is produced.

Fig. 9 is a flowchart showing a setting process executed by the control device before the component mounting substrate is produced.

Fig. 10 is a flowchart showing a printing process performed by the printing apparatus.

Fig. 11 is a flowchart showing a printing process performed by the mounting machine.

Fig. 12 is a flowchart showing a component mounting process performed by the mounting machine.

Fig. 13 is a flowchart showing a component mounting process performed by the mounting machine.

Detailed Description

< relationship between amount of print offset and self-correction effect >

Before describing in detail the embodiments of the component mounting apparatus and the component mounting method according to the present invention, a production system capable of applying the component mounting substrate of the present embodiment and a print offset generated in the production system will be described, and a relationship between a print offset amount and a self-correcting effect obtained by the present inventors will be described.

Fig. 1 is a block diagram showing a production system of a component-mounted substrate in which a component is mounted on a substrate. The production system is provided with: a printing device 10 for printing solder on an electrode formed on a substrate, that is, a so-called substrate electrode; a printing inspection device 20 for inspecting the substrate printed by the printing device 10 to obtain a printing offset; a mounting machine (corresponding to a "component mounting apparatus" of the present invention) 30 that mounts components on a substrate on which solder is printed; and a reflow furnace 40 for performing reflow processing on the substrate mounted with the components. These devices 10, 20, 30, 40 are connected to a Local Area Network (LAN). A control device (server computer) 50 that controls the entire production system is connected to the LAN. Further, between the control device 50 and each of the devices 10, 20, 30, and 40, information related to printing, various kinds of main information of a substrate or an element, and various kinds of processing information including a printing offset amount can be communicated via the LAN. In this production system, the communication between the control device 50 and each of the devices 10, 20, 30, and 40 is performed by a wired LAN, but the communication method and form are not limited to this.

In the production system configured as described above, the printing apparatus 10 prints the solder paste on the substrate according to each specification set by the control apparatus 50. That is, in the printing apparatus 10, the substrate carried in by the substrate carrying-in part is held by the substrate moving stage, and after the substrate is aligned to a predetermined position directly below the stencil, solder printing is performed on the substrate. In this solder printing, the solder printing on the substrate electrode may be shifted. Therefore, in the production system of fig. 1, the printing inspection apparatus 20 performs inspection after the printing process and before the mounting process, and the printing offset amount is obtained for each portion where component mounting is performed.

If the print offset amount is relatively small, the element can be favorably soldered to the substrate electrode by the self-alignment effect as disclosed in patent document 1. At this time, if the component is mounted on the substrate with reference to the solder printing position, the solder between the substrate electrode and a so-called component electrode such as an electrode or a lead formed on the housing of the component is melted and flows by the reflow process performed after the mounting process, and the component is moved to the substrate electrode center position by the self-alignment effect. In this way, if the amount of print deviation is within the correction allowable range in which the mounting position of the component can be corrected to the substrate electrode side by the self-correcting effect exhibited by the melting of the solder, it is preferable to mount the component on the substrate with the solder printing position as a reference.

On the other hand, if the amount of print deviation exceeds the correction allowable range, the following problem may occur if component mounting is performed with reference to the solder print position or the substrate electrode position. Hereinafter, a case where the component mounting process and the reflow process are performed based on the above-described criteria when the print misalignment occurs only in the predetermined direction X will be described as an example.

Fig. 2 is a schematic diagram showing a relationship between a positioning form in the component mounting process and a solder state after the reflow process when a relatively large print misalignment occurs. Here, as shown in fig. 2a, the print of the solder 2 in paste form is shifted by Δ X in the X-axis direction (the thickness of the solder 2 is H0 substantially equal to the thickness of the stencil) with respect to the substrate electrode 1a formed on the substrate 1 and does not reach the adjacent substrate electrode 1 a' (Δ Xb > 0), but the print shift amount Δ X in the X-axis direction is relatively large and exceeds the maximum value Xa (correction allowable value Xa included in the element information described later) of the correction allowable range. At this time, for example, as shown in fig. 2a, if the positional displacement amount Δ X1 of the component 3 is set to be the same as the printing displacement amount Δ X, and the component electrode 3a is aligned with the solder printing position of the printing displacement amount Δ X, and the reflow process is performed after the component 3 is mounted on the substrate 1 with the offset position from the substrate electrode (the thickness of the solder 2 between the component 3 and the substrate 1 becomes smaller than H0 due to the positive pressure acting on the component 3 at the time of mounting the component 3 or the self weight of the component 3), as shown in fig. 2B, a part of the molten solder 2 wets along the surface of the substrate electrode 1a and spreads to the left side of fig. 2B, and the component electrode 3a is pulled to the left side of the fig. 2 by the surface tension of the spread solder 2, but the printing displacement amount Δ X is large, and therefore the wetting spread of the molten solder does not reach the left end of the substrate electrode 1a, even if surface tension is applied, the element 3 cannot be moved leftward in the figure to a position where the element electrode 3a is completely aligned with the substrate electrode 1 a. On the other hand, when the element 3 is mounted on the substrate 1, the thickness of the solder 2 between the element 3 and the substrate 1 becomes smaller than H0, and the solder 2a deviated to the right in the figure from the element 3 melts by the reflow process and tends to spread further to the right, but the solder is pulled by the element 3 slightly moving to the left, and therefore does not reach the adjacent substrate electrode 1a '(the distance Δ Xb from the solder 2a to the adjacent substrate electrode 1 a' is greater than 0). That is, although a solder failure called a solder bridge does not occur after the reflow process, a mounting position failure occurs in which the element 3 cannot be mounted at a correct position with respect to the electrode position of the substrate.

Further, for example, as shown in fig. 2 (C), if the reflow process is performed after the element electrodes 3a of the element 3 are mounted on the substrate 1 with the substrate electrode positions as references, a mounting position failure in which the element 3 cannot be mounted at an accurate position with the electrode positions of the substrate as references does not occur, but the following problem occurs. That is, if the substrate electrode position is taken as a reference, in addition to the solder 2 deviated from the substrate electrode 1a among the printed solders 2, when the component 3 is mounted on the substrate 1, as shown in fig. 2 (D), since the thickness of the solder 2 between the component 3 and the substrate 1 becomes smaller than H0, the solder deviated to the right of fig. 2 (D) with respect to the component 3 is also increased. Thus, the area of contact between the solder 2a that has deviated from the substrate electrode 1a and the element electrode 3a is substantially zero or very small, and the solder 2a that has deviated from the substrate electrode 1a can flow almost freely. On the other hand, since the element 3 does not move even if the reflow process is performed, the flowable solder 2a does not move leftward in the figure. Therefore, the solder 2a that can flow in a free state reaches the adjacent substrate electrode 1 a'. That is, a solder bridge is formed, and a defective soldering occurs.

In contrast to this, as shown in fig. 2 (E), if the component 3 is mounted such that the position of the component 3 is closer to the substrate electrode 1a than the position of the print shift amount Δ X of the print solder 2 during mounting and the shift amount Δ X1 of the position of the component 3 is set to the correction allowable value Xa (which is the maximum value Xa of the correction allowable range), the solder 2 sandwiched between the substrate electrode 1a and the component electrode 3a is melted during reflow processing and wets both the electrodes 1a and 3a to spread leftward in the drawing, and the component electrode 3a is pulled leftward in fig. 2 (E) by the surface tension of the spread solder 2, and the component 3a is moved leftward in fig. 2 (E) until the component electrode 3a of the component 3 is completely aligned with the substrate electrode 1a because the shift amount of the component electrode 3a with respect to the substrate electrode 1a is smaller than the shift amount of fig. 2 (a) because the correction allowable value Xa, as shown in fig. 2 (F), the component 3 can be mounted at a correct position coinciding with the electrode position of the substrate 1 after the reflow process. Further, in addition to the solder 2 deviated from the element 3 among the printed solders 2, when the element 3 is mounted on the substrate 1, the solder 2 deviated from the element 3 to the right in (E) of fig. 2 is increased because the thickness of the solder 2 between the element 3 and the substrate 1 becomes smaller than H0, and the solder 2a formed to deviate from the element 3 is melted by the reflow process and tries to spread further to the right, but due to the pulling of the element 3 moved to the left in (F) of fig. 2, it does not reach the adjacent substrate electrode 1 a' (Δ Xb > 0), and thus a soldering failure such as a solder bridge does not occur.

Further, the solder 2a which is displaced from the substrate electrode 1a before the reflow process shown in fig. 2 (C) flows by the reflow process, and reaches the substrate electrode 1a 'and reaches the overlap length Δ Xc on the substrate electrode 1 a' as shown in fig. 2 (D), and at this time, if the overlap length Δ Xc is relatively small, the mounting position of the component 3 is moved within the correction allowable range to a predetermined position exceeding Δ Xc with respect to the substrate electrode position as a reference, whereby the amount of positional displacement of the component electrode 3a with respect to the substrate electrode 1a is within the small correction allowable range, and therefore, the component 3 is moved leftward in the drawing by the reflow process until the component electrode 3a of the component 3 is completely aligned with the substrate electrode 1a, and the component 3 can be mounted at a correct position with respect to the electrode position of the substrate 1. Since the amount of movement of the component 3 exceeds Δ Xc, the solder 2a that has deviated from the component 3 before the reflow process is pulled by the component 3 moving leftward in the molten state, and does not reach the adjacent substrate electrode 1 a', and a solder bridge is not caused.

Although the case where the print misalignment occurs in the X-axis direction has been described above, the case where the print misalignment occurs in the Y-axis direction (direction perpendicular to the paper surface of fig. 2) perpendicular to the X-axis direction, or in the two-dimensional plane of the X-axis direction and the Y-axis direction may be similarly described above. That is, the allowable correction range is influenced by the direction of the element (the longitudinal direction (YA direction of fig. 3 a) or the width direction (XA direction of fig. 3 a)) when the two element electrodes 3a are arranged side by side).

In the longitudinal direction (YA direction of fig. 3 (a)) when two element electrodes 3a are arranged side by side, the solder 2 wets and spreads on the substrate electrode 3a when melted, and the surface tension of the solder 2 acting between the substrate electrode 3a and the element electrode acts at two points, so that the self-correcting effect is easily obtained, and the correction allowable range is wider than the width direction (XA direction of fig. 3 (a)).

In addition, the correction allowable range is also affected by the size of the element 3. For example, the relatively large element 3 is also large in self weight, and therefore it is difficult to obtain a self-correcting effect. Preferably, as shown in fig. 3 (B), for example, the component information stored in the control device 50 is provided with a "solder reference mark" indicating whether component mounting is permitted or prohibited with reference to the solder printing position. It is preferable that, as the correction allowable range for each component, a correction limit value "correction allowable value XA" of the printing misalignment in the component direction XA and a correction limit value "correction allowable value YA" of the printing misalignment in the component direction YA are stored in advance in a component table for storing component information. The "solder reference mark" may be embodied using attributes such as Boolean (Boolean) type. Before component mounting, when the "solder reference flag" in the component information is set to "1" (True), component mounting is permitted with reference to the solder printing position, and when the print shift amount is within the correction allowance range as shown in fig. 4 (a) (the print shift amount Δ X in the X-axis direction is equal to or less than the correction allowance value Xa, and the print shift amount Δ Y in the Y-axis direction is equal to or less than the correction allowance value Ya), the component mounting position can be corrected with reference to the solder printing position by using the correction effect as shown in fig. 4 (B). On the other hand, although the "solder reference flag" is set to "1" to allow component mounting based on the solder printing position, if the printing shift amount exceeds the correction allowable range as shown in fig. 4 (C) (the printing shift amount Δ Y in the Y-axis direction in fig. 4 (C) exceeds the correction allowable value Ya), component mounting is performed based on the position of the correction allowable range, that is, the position of the correction allowable value Ya as shown in fig. 4 (D), whereby defective soldering can be effectively prevented.

As shown in fig. 4E, if the mounting direction on the board 1 is different for the same component 3, the coordinate system (XA, YA) of the component 3 may be converted into the coordinate system (X, Y) of the mounter 30, and it may be determined whether or not the print shift amount is within the correction allowable range. For example, when the element 3 is mounted on the substrate 1 after being rotated by 90 ° as shown in fig. 4E, it can be determined whether or not the correction effect can be obtained based on whether or not the printing shift amount Δ X in the X-axis direction is equal to or smaller than the "correction allowable value Ya" (see fig. 3B) of the element 3, or whether or not the printing shift amount in the Y-axis direction is equal to or smaller than the "correction allowable value Xa" (see fig. 3B) of the element 3.

Since the above-described relationship exists between the print deviation amount and the self-correcting effect, it is preferable to perform component mounting based on the solder position or the allowable position after determining whether the print deviation amount is within the correction allowable range. The allowable correction range is preferably optimized according to the type of the component 3 and the mounting direction on the substrate 1.

Therefore, in the embodiments described below, based on the relationship between the amount of print deviation and the self-correction effect obtained by the inventors and the examination by the inventors, the component mounting is performed based on the solder position or the allowable position after determining whether the amount of print deviation is within the correction allowable range. However, in the following embodiment, the printing offset amount is not obtained by the printing inspection device 20, but is obtained based on the correction value detected by the printing device 10. That is, in the embodiment described below, the component mounting substrate is produced by a production system that does not include the printing inspection apparatus 20.

< embodiment >

Fig. 5 is a plan view of a mounting machine showing an embodiment of the component mounting apparatus according to the present invention. Fig. 6 is a block diagram showing a main electrical configuration of the mounting machine shown in fig. 5. In the mounting machine 30, a substrate carrying mechanism 302 is provided on a base 311, and can carry the printed substrate 1 on which the cream solder has been printed by the printing apparatus 10 in a predetermined carrying direction (+ X axis direction). More specifically, the substrate conveyance mechanism 302 includes a pair of conveyance belts 321 and 321 for conveying the substrate 1 from the right side to the left side in fig. 5 on the base 311. After the substrate 1 is carried in, the conveyor belts 321 and 321 are stopped at a predetermined mounting work position (position of the substrate 1 shown in the present figure), and the substrate 1 is fixedly held by a holding device not shown in the figure. Next, the electronic component 3 (see fig. 2 to 4) supplied from the component supply unit 304 is transferred onto the substrate 1 by the mounting head 361 mounted on the head unit 306. At this time, the component recognition camera 307 mounted on the head unit 306 performs image recognition of the holding state of the electronic component 3 by the mounting head 361, and outputs the recognition result to the controller (control section) 340 that controls the entire mounter 30. On the other hand, the controller 340 controls the transfer operation based on the image recognition result and the information on the substrate, and mounts the electronic component 3 on the substrate 1 with reference to the position corresponding to the print shift amount as described later. After the mounting process of all the components to be mounted on the substrate 1 is completed, the substrate transfer mechanism 302 carries out the substrate 1.

The component supply unit 304 is provided on the front side (+ Y axis direction side) and the rear side (-Y axis direction side) of the substrate transfer mechanism 302 configured as described above. These component supply units 304 are provided with a plurality of tape feeders 304 a. Each tape feeder 304a is provided with a reel (not shown) for winding a tape for storing and holding the electronic component 3, and the electronic component 3 can be supplied to the head unit 306. That is, chip-type electronic components 3 in the form of small pieces, such as Integrated Circuits (ICs), transistors, and capacitors, are stored and held on the respective tapes at predetermined intervals. The tape feeder 304a feeds the tape from the reel to the head unit 306 side, whereby the electronic components 3 in the tape are intermittently fed, and as a result, the mounting head 361 of the head unit 306 can pick up the electronic components 3.

The head unit 306 conveys the electronic component 3 to the substrate 1 while being sucked and held by the mounting head 361, and transfers the electronic component to a position instructed by a user. The head unit 306 has 6 mounting heads 361F arranged in a line in the X-axis direction on the front side and 6 mounting heads 361R arranged in a line in the X-axis direction on the rear side, and a total of 12 mounting heads 361.

In the head unit 306, the 6 mounting heads 361F extending in the vertical direction Z are provided in a row at equal intervals in the X-axis direction (the direction in which the substrate 1 is conveyed by the substrate conveying mechanism 302). Further, the mounting head 361F is provided with a rear row on the rear side (the side in the Y axis direction) which is configured in the same manner as the front row. That is, the 6 mounting heads 361R extending in the vertical direction Z are provided in a row at equal intervals in the X-axis direction.

Further, a component suction nozzle (not shown) is attached to a distal end portion of each mounting head 361, each component suction nozzle is communicable with any one of the same negative pressure generating device, the same positive pressure generating device, and the atmosphere via an electric switching valve not shown, and a negative pressure suction force from the negative pressure generating device is supplied to the component suction nozzle by the control of the controller 340, whereby a lower end portion (distal end portion) of the component suction nozzle can suck the upper surface of the electronic component 3 and hold the component. In contrast, if the positive pressure from the positive pressure generating device is supplied to the component nozzles by the control of the controller 340, the suction holding of the electronic component 3 by the mounting head 361 is released, and the electronic component 3 is instantaneously mounted on the substrate 1 by the positive pressure. Then, after the electronic component 3 is mounted, the component suction nozzle is opened to the atmosphere. In this way, in the head unit 306, the controller 340 controls the supply of the negative pressure suction force and the positive pressure, and the electronic component 3 can be mounted/detached.

Each mounting head 361 is movable up and down (movement in the Z-axis direction) with respect to the head unit 306 by driving of a nozzle up-and-down driving mechanism using a Z-axis motor 381 as a driving source, and is rotatable around a nozzle center axis by driving of a nozzle rotation driving mechanism using an R-axis motor 382 that rotates around the Z-axis as a driving source. Among these drive mechanisms, the nozzle elevation drive mechanism elevates the mounting head 361 between a lowered position for suction or mounting and a raised position for conveyance or imaging. On the other hand, the nozzle rotation driving mechanism is a mechanism that rotates the component nozzle as necessary to align the direction of the electronic component 3 with the mounting direction or to correct a shift in suction in the R-axis direction, and the electronic component 3 can be positioned at a predetermined position in the R-axis direction during mounting by rotation driving.

The head unit 306 is movable in the X-axis direction and the Y-axis direction (directions orthogonal to the X-axis direction and the Z-axis direction) within a predetermined range of the base 311 in order to transfer the electronic component 3 sucked by the mounting heads 361 between the component supply unit 304 and the substrate 1 and mount the electronic component on the substrate 1. That is, the head assembly 306 is supported movably along the X axis with respect to the mounting head support member 363 extending in the X axis direction. Both ends of the mounting head supporting member 363 are supported by fixed rails 364 in the Y axis direction, and are movable in the Y axis direction along the fixed rails 364. The head unit 306 is driven in the X-axis direction by an X-axis motor 365 via a ball screw 366, and the head supporting member 363 is driven in the Y-axis direction by a Y-axis motor 367 via a ball screw 368.

In this way, the head unit 306 can carry the electronic component 3 sucked by the mounting head 361 from the component supply unit 304 to the target position. In the present embodiment, the head unit 306 is provided with a component recognition camera 307 for sequentially picking up images of the suction-held state of the electronic components 3 on the mounting head 361 during component conveyance and recognizing the images. Further, a substrate recognition camera 308 is mounted on the head unit 306 in addition to the component recognition camera 307. The substrate recognition camera 308 has a function of imaging a plurality of reference marks attached to the substrate 1 located at the mounting work position to recognize the substrate position and the substrate direction as images. Further, by moving the head unit 306 above the component supply position of the feeder 304a, the component or the component storage portion of the tape fed by the feeder 304a can be imaged from above by the board recognition camera 308.

The mounter 30 configured as described above is provided with a controller 340 for controlling the entire mounter. The controller 340 includes an arithmetic processing unit 341, a storage unit 342 such as a hard disk drive, a motor control unit 343, an image processing unit 344, and a server communication control unit 345. The arithmetic processing unit 341 is constituted by a CPU or the like, and controls each unit of the mounter in accordance with a mounting program stored in advance in the storage unit 342, and component mounting is performed with reference to a position corresponding to the print offset amount. The storage unit 342 may store various main information and processing information necessary for the mounting operation of the mounting machine 30. The main information and the processing information are information processed by the controller 510 of the control device 50 or another computer.

The motor controller 343 is electrically connected to the X-axis motor 365, the Y-axis motor 367, the Z-axis motor 381, and the R-axis motor 382 to drive and control the motors. Further, encoders (not shown) for outputting pulse signals according to the rotation states of the motors are attached to the motors 365, 367, 381, and 382, respectively. The pulse signals output from the encoders are introduced into the controller 340, and the arithmetic processing unit 341 receiving these signals acquires information on the rotation amounts of the axis motors 365, 367, 381, and 382, and controls the axis motors 365, 367, 381, and 382 together with the motor control unit 343, thereby moving the component suction nozzle to an arbitrary position on the base 311.

The image processing unit 344 is electrically connected to the component recognition camera 307 and the board recognition camera 308, and the imaging signals output from these cameras 307 and 308 are introduced into the image processing unit 344. Next, the image processing unit 344 analyzes the device image and the substrate image based on the introduced imaging signal. This allows the type, suction condition, suction position, and suction direction of the electronic component 3 on the component suction nozzle to be recognized as images, detects whether the electronic component 3 on the suction nozzle is proper, whether the suction is good, and a deviation in suction time, and also recognizes the substrate position and the substrate direction as images. Further, the positional relationship between the component or the component accommodation portion and the component supply position can be recognized, whereby it is possible to detect a positional deviation of the component or the like with respect to the component supply position, or whether the component is conveyed to the component supply position.

The mounter 30 is provided with a display/operation unit 350 for displaying main information, processing information, and the like. The display and operation unit 350 is also used for inputting information such as various data and commands to the controller 340 by the operator. The mounter 30 is also provided with a server communication control unit 345 for exchanging various data such as main information and processing information with the control device 50.

The control device 50 includes the controller 510 that can process the main information or the process information as described above. The controller 510 is provided with an arithmetic processing unit 511 including a CPU or the like, a storage unit 512 including a hard disk drive or the like, and a communication control unit 513, and can process the main information or the processing information, generate and edit a setting file at the time of operation of the printing apparatus 10 or the mounter 30, and control the entire production system. The storage unit 512 stores a table for storing various information necessary for the printing process and the mounting process. Here, the table refers to 1 or more data sets in which information is stored in a two-dimensional matrix. In the following description, following the definition of e.f.codd, a column (data item) of a table is referred to as an Attribute (Attribute), and a row (a set of information) of the table is referred to as a Tuple (Tuple). Further, any combination of attributes and tuples is referred to as a data set.

As shown in fig. 7, the storage section 512 stores a print table (T10 to T14), a board table (T20 to T23), an element table (T30), and the like. Then, as will be described later, the production of the component mounting substrate is performed in accordance with the main information and/or the processing information stored in the print table, the substrate table, and the component table.

The print table includes template master data T10, template opening T11, print data T12, and opening data T14. Tables T10, T11 include master information of the templates required for printing.

The template master data T10 includes coordinates X, Y of a fiducial mark for each template, and template fixing time offsets Δ X1, Δ Y1, and Δ R1 generated when the template is fixed at the time of printing can be calculated based on these coordinate data. In the present embodiment, the template master data T10 can have registered therein the misalignment offset values Δ X3, Δ Y3, and Δ R3, and the misalignment correction values Δ X3, Δ Y3, and Δ R3. The print registration positional displacement amounts Δ X3, Δ Y3, and Δ R3 are processing data for updating the displacement amount of the substrate with respect to the template for each template, and the initial value is set to 0. The alignment-time offset correction values Δ X3, Δ Y3, and Δ R3 are values that are updated every time the substrate is printed. Since the substrate 1 is moved to perform alignment with the template, the offset correction value is a positive value (Δ X3, Δ Y3, Δ R3) at the time of alignment.

The template opening T11 stores master data regarding the printing openings formed in the template for each opening.

The print data T12 stores various process data for each substrate to be produced. The print data T12 may store the template fixing offset amounts Δ X1, Δ Y1, and Δ R1, the substrate fixing offset amounts Δ X2, Δ Y2, and Δ R2 generated when the substrate is fixed to the printing table, the alignment offset amounts Δ X2, Δ Y2, and Δ R2 when the substrate and the template are aligned, and correction values corresponding to these offset amounts.

The opening data T14 stores processing data for each opening of the substrate to be produced. In the illustrated embodiment, the template opening offset may be stored for each opening of the template based on the coordinates of the fiducial marks of the template master data T10.

The substrate table includes substrate master data T20, component mounting master data T21, mounting data T22, and mounting detail data T23. The substrate master data T20 stores various master data (numbers, dimensions, coordinates of reference marks, and the like) of the substrate. The component mounting master data T21 holds information of mounted components for each substrate. The component mounting master data T21 also stores component mounting coordinates Xp, Yp, and Rp. The controller 340 of the mounter 30 refers to the board master data T20 and the component mounting master data T21, and thus refers to the component mounting coordinates Xp, Yp, and Rp for each component mounted on the board.

The mounting data T22 holds processing information for each substrate produced. In the mounting data, the substrate fixing offsets Δ X4, Δ Y4, and Δ R4 and the correction values Δ X4, Δ Y4, and Δ R4 generated when the substrate is fixed at the mounting position can be stored. The mounting specification data holds processing data for each component of the produced substrate. In the illustrated example, the component suction-time offset amounts Δ X5, Δ Y5, Δ R5 and correction values Δ X5, Δ Y5, Δ R5 generated when the component is sucked by the component suction nozzle can be stored. The mounting specification data T23 may store solder printing position reference coordinates Xq, Yq, and Rq, which will be described in detail later. Further, in the illustrated embodiment, in order to determine the orientation of the same element, an orientation flag is included in the attribute.

The element table includes element master data T30. As shown in fig. 3 (B), the component master data T30 includes a solder reference mark, XA correction permission value, and YA correction permission value, in addition to the number for specifying the component.

In FIG. 7, each of tables T10-T30 includes a Primary Key (PK) that uniquely determines a tuple and an external key (FK) that refers to the primary key, respectively. Therefore, by adding the value of the main keyword to the external keyword, the data can be associated. Thereby, as indicated by an arrow in fig. 7, for example, a component mounting coordinate can be associated with each component of the produced substrate. Also, the arrows in fig. 7 indicate the association (relationship) between tables. The correction values indicated by x in fig. 7 are derived attributes whose values can be derived from offsets by calculation, and do not necessarily need to be registered in the corresponding tables. In the present embodiment, all the initial values of the correction values are 0.

The table shown in fig. 7 is a theoretical structure, and does not necessarily need to be physically present in the same location. Therefore, not only all the data can be stored in the storage unit 512 of the control device 50 as in the present embodiment, but also the respective data can be physically distributed. In either case, the data stored in the table shown in fig. 7 can be referred to and updated by the printing apparatus 10, the mounting machine 30, and the control apparatus 50 theoretically as a single database. As a specific data reference method, a necessary data set is edited in a setting file and exchanged between apparatuses. For example, in the present embodiment, the offsets Δ X0 and Δ Y0 of the template openings and the positional offsets Δ X3, Δ Y3 and Δ R3 at the time of print registration are edited in the setting file and are directly transferred from the printing apparatus 10 to the mounting apparatus 30, but the offsets Δ X3, Δ Y3 and Δ R3 at the time of print registration may be directly transferred from the printing apparatus 10 to the mounting apparatus 30, or may be transferred via the storage unit of the control apparatus 50, and at this time, the storage unit of the control apparatus 50 functions as a buffer for the offsets Δ X0 and Δ Y0 of the template openings and the positional offsets Δ X3, Δ Y3 and Δ R3 at the time of print registration, and the printing apparatus 10 and the mounting apparatus 30 may edit and transmit the offsets Δ X0 and Δ Y0 of the template openings and the positional offsets Δ X3, Δ Y3 and Δ R3 at the. Alternatively, a database management system (DBMS) may be constructed for each device, and each device 10, 30, or 50 may refer to and update the table of fig. 7. At this time, when the printing apparatus 10, the mounter 30, and the control apparatus 50 refer to and update data, the DBMS ensures serializability (Serializable) of the data. Therefore, the problem of the mismatch of the data before the mounter 30 refers to the printing apparatus 10 for update can be prevented. The review or update of data may be embodied in programming of event procedures or SQL in each device.

Reference numeral 520 in fig. 6 denotes a display/operation unit for displaying a graph or the like of the data stored in the table shown in fig. 7, or for inputting information such as various data or instructions stored in the table shown in fig. 7 to the controller 510 by an operator.

Next, an operation of producing the component mounting board by the production system (printing apparatus 10+ mounting apparatus 30+ reflow oven 40+ control apparatus 50) including the mounting apparatus 30 configured as described above will be described with reference to fig. 8 to 13.

Fig. 8 is a flowchart showing a setting process executed by the printing apparatus before producing the component mounting substrate. Fig. 9 is a flowchart showing a setting process executed by the control device before producing the component mounting substrate. Fig. 10 is a flowchart showing a printing process performed by the printing apparatus. Fig. 11 to 13 are flowcharts showing a component mounting process performed by the mounting machine.

When the component mounting substrate is produced by the above-described production system, before the production, a setting process for adapting to the production of the component mounting substrate is executed by the printing apparatus 10 and the control apparatus 50. First, a controller (not shown) provided in the printing apparatus 10 executes a setting process shown in fig. 8. That is, the controller controls each part of the printing apparatus 10 to edit the print table as follows. First, in step S10, a data set corresponding to the above-described element mounting board in the table of fig. 7 is read out and written into a storage unit (not shown) provided in the controller.

In the printing apparatus 10, the stencil having the opening corresponding to the electrode pattern formed on the substrate 1 is fixed to the stencil holding portion, but the fixing position of the stencil may be fixed at a position deviated from a predetermined position. Therefore, in the next step S11, the fiducial marks marked on the lower surface of the template are picked up by the template recognition camera, and template fixing timing offsets Δ X1, Δ Y1, and Δ R1 in the X-axis direction, the Y-axis direction, and the R-axis direction of the printing apparatus 10 corresponding to the X-axis direction, the Y-axis direction, and the R-axis direction of the mounter 30, respectively, are calculated based on the picked-up images (step S12). In the printing apparatus 10 that performs printing by moving the substrate 1 relative to the fixed stencil and performing registration, the "stencil-fixing-time shift correction value" that is the amount of movement of the substrate 1 to compensate for the fixed shift of the stencil in the registration is Δ X1, Δ Y1, and Δ R1 that are the same as the fixed shift amounts of the stencil in each of the X-axis direction, the Y-axis direction, and the R-axis direction. (step S14).

Then, the entire template is photographed by the template recognition camera (step S15). Since the template entire image, which is the template imaging result obtained in this manner, includes the reference mark and the template opening, information such as the center position and the size of each template opening with the reference mark is calculated based on the template imaging result, and the data is stored in the print data T12 of the print table (step S16).

In control device 50, controller 510 executes the setting processing shown in fig. 9. That is, the data set relating to the print table edited by the printing apparatus 10 is written from the storage unit 512 into the working memory area, and the tuple corresponding to the component mounting board in the board table stored in the storage unit 512 is read out and written into the working memory area (step S20). Then, the counting variable i is initialized to 1 (step S21), and the component mounting coordinates Xp, Yp, and Rp set in the component mounting master data T21 of the board table are read (step S22). Next, the center coordinates of the template openings corresponding to the read element mounting coordinates Xp, Yp, and Rp and the size information with reference to the reference mark of the template are read from the opening data T14 in the print table (step S23). Next, based on the mounting coordinates of the component with reference to the reference mark of the substrate and the position of the stencil opening with reference to the reference mark of the stencil, deviations Δ X0 and Δ Y0 of the stencil opening from the mounting coordinates of the component are calculated. The offsets Δ X0 and Δ Y0 due to the opening processing error with respect to the template are stored as template opening offsets Δ X0 and Δ Y0 in the X-axis direction and the Y-axis direction of the mounter 30 in association with the mounting coordinates (step S24). Subsequently, the variable i is incremented (step S25), and it is determined whether all the processing has ended (step S26). In this way, the calculation processing of the offsets X0 and Y0 in steps S22 to S24 is performed for all the mounted coordinates. When it is determined in step S26 that all the processes have ended, the process ends. Through the processing of fig. 9, the offsets X0 and Y0 registered in the opening data T14 of the print table are registered in association with the component mounting coordinates Xp, Yp, and Rp for each piece of component mounting information of the board registered in the board table.

When the processing of fig. 9 is completed, the controller of the printing apparatus 10 controls each unit of the printing apparatus 10 in accordance with the information updated in the print table, and executes the printing processing shown in fig. 10. In this printing process, the printing apparatus 10 refers to the data sets necessary for the printing process from the respective tables stored in the storage unit 512 (step S30).

Since the substrate 1 on which the electrode pattern is formed is carried into a predetermined substrate fixing position and fixed, and the position of the substrate 1 may be shifted when the substrate 1 is fixed at the substrate fixing position, the printing apparatus 10 photographs reference marks of the substrate 1 with the substrate recognition camera, and obtains substrate fixing shift amounts Δ X2, Δ Y2, and Δ R2 in the X-axis direction, the Y-axis direction, and the R-axis direction of the printing apparatus 10 based on the photographed images (step S31). The calculated substrate fixing time shift amounts Δ X2, Δ Y2, and Δ R2 are registered in a tuple of the print data T12 corresponding to the substrate to be processed. In a printer that performs registration by moving a substrate 1 relative to a fixed stencil and performs printing, a movement amount of the substrate 1 at the time of registration, which compensates for a fixed offset of the substrate 1, that is, a "substrate-fixing-time offset correction value" can be calculated as values (- Δ X2, - Δ Y2, - Δ R2) obtained by inverting positive and negative substrate-fixing offset amounts Δ X2, Δ Y2, and Δ R2 in each of the X-axis direction, the Y-axis direction, and the R-axis direction (step S32).

Then, the template fixing time shift correction values Δ X1, Δ Y1, and Δ R1 and the substrate fixing time shift correction values Δ X2, - Δ Y2, and Δ R2 in the X-axis direction, the Y-axis direction, and the R-axis direction of the printing apparatus 10 set in the print data T12 of the print table are added to each other, and the alignment time shift amounts Δ X3, Δ Y3, and Δ R3 stored in the template main data T10 are integrated (updated) (step S33). The printing apparatus 10 moves the substrate 1 in the X-axis direction, the Y-axis direction, and the R-axis direction based on the updated displacement amounts Δ X3, Δ Y3, and Δ R3 at the time of alignment, and positions the substrate 1 and the template so that the reference marks on the lower surface of the template are aligned with the reference marks on the substrate. Then, at the same time as the positioning of the substrate 1 and the template is started, the substrate 1 is raised toward the template, and the substrate 1 is brought into close contact with the lower surface of the template in a state where the positioning of the substrate 1 and the template is completed. Subsequently, the solder in paste form is supplied to the upper surface of the stencil, and the squeegee is moved in the Y-axis direction while controlling the printing load and the moving speed. Thereby, solder is printed on the electrodes formed on the substrate 1 through the opening portions of the stencil (step S34).

In the present embodiment, the alignment confirmation openings are provided in the mask, the printed substrate 1 is imaged by the substrate recognition camera 1, and the alignment offset amounts Δ X3, Δ Y3, and Δ R3 are calculated from the positions of the printed solder printed through the alignment confirmation openings on the substrate 1 (step S35), and are updated as alignment offset correction values Δ X3, Δ Y3, and Δ R3 (step S36). In the update operation, the updated data is supplied to the mounting machine in the form of a setting file matched with the database of the control device 50.

After the printing process on the substrate 1 is completed, the substrate 1 is moved downward and returned by the amount moved for positioning the substrate 1 and the mask to the original position. After the fixing of the substrate 1 is released, the printed substrate 1 is carried out to the mounting machine 30 by a substrate carrying mechanism such as a carrying belt (step S37).

In the mounter 30 that has sent the printed substrate 1, the controller 340 controls each section of the mounter 30 in accordance with the mounting program stored in the storage section 342, and executes the component mounting process shown in fig. 11 to 13.

In this installation program, communication is first established with the control apparatus 50, and a data set necessary for the installation processing is referred to (step S40). In this case, the data set may be received at once in a batch unit, stored in the storage unit 342, and then the communication may be terminated, or the updated data may be received for each substrate. Then, the offsets Δ X0 and Δ Y0 of the respective template openings and the offsets Δ X3, Δ Y3 and Δ R3 at the time of alignment are referred to at this time.

The controller 340 carries in and fixes the substrate 1 carried from the printing apparatus 10 based on the data set referred to (step S41). Specifically, when the board 1 is caused to stand by at a predetermined standby position and component mounting processing can be performed by the mounting machine 30, the board 1 on which components are not mounted on the standby board is carried in by the board conveying mechanism 302, stopped at a predetermined mounting work position (the position of the board 1 shown in fig. 5), and the board 1 is fixed and held by a holding device not shown. Since the substrate 1 may be displaced when the substrate is fixed, the controller 340 images the reference mark of the substrate 1 by the substrate recognition camera 308, calculates the fixed displacement amounts Δ X4, Δ Y4, and Δ R4 of the substrate 1 in the X-axis direction, the Y-axis direction, and the R-axis direction of the mounter 30 as "substrate fixing displacement correction values" based on the imaged image, and stores the calculated values in the mounting data T22 (steps S42 and S43).

In the next step S44, the variable G is initialized to 1. The variable G indicates a group (component group) of components that are sucked by the component suction nozzle at one time. Then, in order to process the information related to each group of elements, the variable P is initialized to 1 in step S45. The variable P represents the number of times the element in group G is processed.

When the preparation for mounting components is completed, information on components belonging to the mounting group of the G-th group among the component groups to be mounted on the board 1 and the like are read from the setting file provided by the printing apparatus 10 (step S46). The component information is various information for mounting on the substrate 1, and includes attributes such as a solder reference mark, a correction allowable value XA in the component direction XA, and a YA correction allowable value YA in the component direction YA, in addition to the component size and the like, as shown in fig. 3 (B) or fig. 7. In addition, if at this stage, component information and the like have been stored in the storage portion 342 of the mounter 30, these pieces of information are used as long as serializability of data is maintained.

In the next step S46, the variable P is incremented, and steps S46, S47 are repeated until the information of all the elements within the G-th group is acquired in step S48.

Referring to fig. 12, after acquiring all the component information, the mounter 30 moves the head assembly 306 to the component supply section 304, and sucks the electronic component 3 by the component suction nozzle mounted at the distal end portion of the mounting head 361 (step S50). Then, the mounter 30 initializes the variable P to 1 again (step S51), and refers to the direction flag corresponding to the pth component from the component information (step S52). If the flag has a value of 1(True), the mounter 30 performs processing after converting the coordinates of the correction permission values Xa, Ya by 90 ° in the following processing (step S53).

Then, the mounting head 30 images the suction state of the component 3 by the component nozzle by the component recognition camera 307, calculates the suction-time offsets Δ X5, Δ Y5, and Δ R5 in the X-axis direction, the Y-axis direction, and the R-axis direction based on the imaging result, and stores them in the mounting detail data T23 of fig. 7 (step S54). Further, — Δ X5, - Δ Y5, and- Δ R5 for inverting the positive and negative directions are calculated as "shift correction values at the time of adsorption", and stored in the mounting detail data T23 of fig. 7 (step S55).

Here, when the head unit 306 is directly driven and controlled to be mounted on the substrate 1 in accordance with the component mounting coordinates Xp, Yp, and Rp set in the component mounting master data T21 in the substrate table, the electronic component 3 sucked by the component suction nozzle is mounted at a position different from the electrode formed on the substrate 1 due to the influence of the above-described offset at the time of fixing the substrate and the offset at the time of sucking the component. Therefore, in the present embodiment, in step S56, the fixed offset correction values Δ X4, Δ Y4, and Δ R4 calculated in step S43 and the adsorption-time offset correction values Δ X5, - Δ Y5, and- Δ R5 calculated in step S55 are added to the device-mounted coordinates Xp, Yp, and Rp, respectively, to correct the device-mounted coordinates Xp, Yp, and Rp (this correction calculation is referred to as "coordinate calculation a"). By mounting the component 3 on the component mounting coordinates Xp, Yp, and Rp thus corrected, the lead 3a of the electronic component 3 can be aligned with the substrate electrode 1a formed on the substrate 1. That is, mounting the element 3 on the element mounting coordinates Xp, Yp, and Rp obtained by the coordinate calculation a means mounting the element 3 on the substrate 1 with the electrode position as a reference.

Here, if the solder 2 is printed accurately on the substrate electrode 1a and the printing offset amount is zero, it is preferable to mount the component 3 on the component mounting coordinates Xp, Yp, and Rp obtained by the coordinate calculation a. However, it is difficult to perform the printing process without causing any printing misalignment. Therefore, in the present embodiment, it is determined whether or not the "solder reference flag" included in the component information is set to "1" to allow component mounting with the solder printing position as a reference (step S57). If the determination result is "True", that is, the solder reference flag is 1, a series of processes to be described next are executed (steps S58 to S66), and component mounting is executed on the basis of further correcting the component mounting coordinates Xp, Yp, Rp (step S69). On the other hand, if the determination result is "False", that is, if the solder reference flag is 0 or Null, the component 3 is mounted on the component mounting coordinates Xp, Yp, Rp obtained by the coordinate calculation a of step S56, that is, the component 3 is mounted on the substrate 1 with the electrode position as a reference (step S69).

In step S58 of the series of processing, coordinates (the center position of the printed solder pattern related to soldering of the corresponding component in the coordinate system set on the base 311 of the mounting machine 30) Xq, Yq, and Rq (this calculation is referred to as "coordinate calculation B") are calculated in consideration of the stencil opening offsets Δ X0 and Δ Y0 and the misalignment offsets Δ X3, Δ Y3, and Δ R3 at the calculated coordinates (the component mounting positions in the coordinate system set on the base 311 of the mounting machine 30) Xp, Yp, and Rp obtained in the coordinate calculation a of step S56. That is, according to the following numerical formula (1)

Xq＝Xp+ΔX0+ΔX3

Yq＝Yp+ΔY0+ΔY3 (1)

Rq＝Rp+ΔR3

Coordinates Xq, Yq, and Rq are obtained.

Referring to fig. 13, in step S60, the difference (Δ X0+ Δ X3) between the X-axis coordinate Xq of the calculated coordinates obtained in step S58 and the X-axis coordinate Xp of the component mounting coordinates obtained in step S56 is obtained, and it is determined whether or not the absolute value of the difference is equal to or greater than the correction allowable value Xa set in the component information. In this way, in the present embodiment, the difference between the X-axis coordinate Xq and the X-axis coordinate Xp is obtained to obtain the print offset amount, and if the print offset amount exceeds the correction allowable value Xa, that is, if the print offset amount is relatively large and the correction effect cannot be expected (see fig. 2), the correction allowable value Xa is added to the X-axis coordinate Xp of the component mounting coordinates obtained in step S56 (subtracted if the difference is negative) to correct the component mounting coordinates (step S61). At this time, by executing step S69 described later, the element 3 is mounted on the substrate 1 with the allowable position as a reference in the X-axis direction as shown in fig. 2 (E).

On the other hand, if the print shift amount is equal to or less than the correction allowable value Xa, that is, if the self-correction effect can be obtained, the value of the X-axis coordinate Xp of the element mounting coordinate obtained in step S56 is rewritten to the value of the X-axis coordinate Xq calculated in step S58 (step S62). At this time, by executing step S69 described later, the element 3 is mounted on the substrate 1 with the solder printing position as a reference in the X-axis direction.

In the Y-axis direction, the Y-axis coordinate Yp of the element mounting coordinate is corrected in the same manner as in the X-axis direction (steps S63 to S65). That is, it is determined whether or not the absolute value of the difference between the Y-axis coordinate Yq of the calculated coordinates obtained in step S58 and the Y-axis coordinate Yp of the element mounting coordinates obtained in step S56, that is, the print shift amount in the Y-axis direction is equal to or greater than the correction allowable value Ya (step S63). Then, if the amount of print deviation in the Y-axis direction exceeds the correction allowance value Ya, that is, if the print deviation is relatively large and the correction effect cannot be expected, the correction allowance value Ya is added to the Y-axis coordinate Yp of the component mounting coordinates obtained in step S56 (subtracted if the difference is negative) to correct the component mounting coordinates (step S64). On the other hand, if the printing offset amount is equal to or less than the correction allowable value Ya, that is, if the self-correction effect is obtained, the value of the Y-axis coordinate Yp of the element mounting coordinate obtained in step S56 is rewritten to the value of the Y-axis coordinate Yq calculated in step S58 (step S65).

In the R-axis direction, regardless of the amount of the print shift amount, the value of the R-axis coordinate Rp of the element mounting coordinate obtained in step S56 is rewritten to the value of the R-axis coordinate Rq calculated in step S58 (step S66).

The mounter 30 increases the variable P (step S67), and determines whether or not the correction processing of the component mounting coordinates Xp, Yp, Rp has been completed for all components in the G-th group (step S68). If the unprocessed element is r, the processing in step S52 is repeated. On the other hand, if the correction processing of the component mounting coordinates Xp, Yp, Rp of all the components in the G-th group is completed, the mounter 30 moves the component suction nozzles and then mounts the components sucked and held by the component suction nozzles onto the substrate 1 (step S69). At the time of this mounting, if the solder reference flag is set to "1" to allow component mounting with the solder printing position as a reference, the component mounting coordinates Xp, Yp, Rp are corrected in accordance with the printing shift amount. Further, if the solder reference flag is set to 0 or Null, the component mounting coordinates Xp, Yp, Rp calculated in step S56 are used as they are.

When the mounting of the G-th group of components is finished, the mounter 30 increases the variable G (step S70), and determines whether the mounting process of all groups has been completed (step S71). If such component mounting of all the components is not completed (if no is determined in step S71), the processing from step S45 in fig. 11 is repeated.

If the mounting of all the components on the substrate 1 is completed, the substrate 1 on which the components have been mounted is carried out of the mounting machine 30 by the substrate carrying mechanism 302 (step S72), and the reflow process is performed in the reflow furnace 40 next.

As described above, if the printing deviation amount is within the correction allowable range (smaller than the correction allowable value Xa in the X-axis direction and smaller than the correction allowable value Ya in the Y-axis direction), the component 3 is mounted with the solder printing position as a reference, and the self-correcting effect is effectively exhibited by performing the reflow process after the component mounting process, so that the component 3 can be mounted on the substrate well. Further, if the print deviation amount exceeds the correction allowable range (larger than the correction allowable value Xa in the X-axis direction and larger than the correction allowable value Ya in the Y-axis direction) and the correction effect cannot be expected, the component 3 is mounted on the substrate 1 with reference to the allowable limit position (the position of the correction allowable value Xa in the X-axis direction and the position of the correction allowable value Ya in the Y-axis direction), and therefore, as described above, the occurrence of the soldering failure can be prevented and the component 3 can be mounted on the substrate 1 satisfactorily.

The present invention is not limited to the above embodiments, and various modifications other than the above embodiments may be made without departing from the spirit of the invention. For example, in the above embodiment, the printing shift amount is calculated in consideration of the mask opening shifts Δ X0 and Δ Y0 calculated based on the mask image in addition to the shift amounts Δ X3, Δ Y3 and Δ R3 at the time of alignment, but the printing shift amount may be calculated in consideration of only one of them. Further, the printing inspection apparatus 20 may be incorporated into the production system, and the printing offset amount detected by the printing inspection apparatus 20 may be used. In addition, if the printing shift amount is calculated in consideration of only the stencil opening shifts Δ X0 and Δ Y0 calculated based on the stencil image, step S35 in fig. 10 can be omitted, and the time taken by the camera or the like can be saved.

Further, when the print deviation is equal to or larger than the correction allowable range as in the above-described embodiment, the position of the component 3 to be mounted with the component is set to the correction allowable value, or the position of the component 3 is deviated from the substrate electrode position as the reference to the predetermined position within the correction allowable range (that is, the solder is deviated to the predetermined position close to the substrate electrode 1a within the solder deviation range and within the correction allowable range, Δ X1 is secured as shown in (E) of fig. 2), whereby the solder 2 sandwiched between the substrate electrode 1a and the component electrode 3a is melted in the reflow process and is spread to the left of (E) of fig. 2 by wetting to both the electrodes 1a and 3a, and the component electrode 3a is pulled to the left of (E) of fig. 2 by the surface tension of the spread solder 2, and as shown in (F) of fig. 2, the component 3 is moved to the left of the component 3 so that the component electrode 3a is aligned with the substrate electrode 1a, so that the component 3 can be mounted at a correct position with reference to the electrode position of the substrate 1 after the reflow process. The solder 2a that has deviated from the element 3 before reflow is melted by the reflow process and tends to spread further rightward, but is pulled by the element 3 moving leftward in the drawing, and therefore does not reach the adjacent substrate electrode 1 a', and a soldering failure such as a solder bridge does not occur.

The object of the present invention is not limited to the mounting machine having the above-described configuration, and can be applied to a component mounting apparatus for mounting components on a substrate. The component mounting apparatus that can use the present invention is not limited to an apparatus incorporated in a production system, and the present invention can be used for a mounting machine that works alone.

Claims (7)

1. A component mounting apparatus for mounting a component on a substrate on which an electrode is formed and solder is printed on the electrode, the component mounting apparatus comprising:

a head assembly mounting the component to the substrate;

a control unit for controlling the operation of the head unit and adjusting the mounting position of the component according to the printing offset of the solder with respect to the electrode; wherein,

the control section mounts the component with reference to an off-position of the solder on the substrate when the print shift amount is within a correction allowable range that can correct the mounting position of the component to the electrode side by a self-correcting effect based on melting of the solder,

the control unit mounts the element with reference to a predetermined position in a range where solder is deviated from the substrate, the predetermined position being a correction allowable range and being close to the electrode, when the print deviation amount exceeds the correction allowable range.

2. A component mounting apparatus in accordance with claim 1, wherein:

the control unit sets a position of a correction allowable value, which is a maximum value of the correction allowable range, as the designated position.

3. A component mounting apparatus in accordance with claim 1, wherein:

the control unit sets the correction allowable range according to the type of the element.

4. A component mounting apparatus in accordance with claim 1, wherein:

the control unit sets the correction allowable range according to the direction of the element.

5. A component mounting apparatus in accordance with claim 1, wherein:

the control unit controls the operation of the head unit in consideration of an offset amount at the time of fixing the substrate on which the component is mounted, which is an offset amount generated at the time of fixing the substrate.

6. A component mounting apparatus in accordance with claim 1, wherein:

the control unit controls the operation of the head unit in consideration of a component suction offset amount generated when a component mounted on a substrate is sucked.

7. A component mounting method for mounting a component on a substrate on which an electrode is formed and solder is printed on the electrode, the component mounting method comprising:

determining a printing offset amount of the solder with respect to the electrode;

a step of comparing the printing offset amount with a correction allowable range that is a correction allowable range in which the mounting position of the component can be corrected to the electrode side by a self-correcting effect exhibited based on melting of the solder;

and mounting the component with reference to a position of the solder deviated from the substrate as a reference when the print deviation amount is within the correction allowance range, and mounting the component with reference to a position of the solder deviated from the substrate by the electrode in a range of the solder deviated from the substrate as a reference when the print deviation amount is beyond the correction allowance range.

Images