JP4751948B1 - Component mounting apparatus and component mounting method - Google Patents

Abstract

By appropriately adjusting the mounting position of a component in accordance with the amount of printing misalignment, the component is mounted on a substrate satisfactorily while preventing the occurrence of solder failure.
A paste-like solder 2 is printed on an electrode 1a formed on a substrate 1 so as to be shifted by ΔX in the X-axis direction, and the amount of printing deviation ΔX in the X-axis direction is relatively large, and an allowable correction range. Xa is exceeded. In this case, when the component 3 is mounted at a predetermined position that is closer to the substrate electrode 1a than the position where the solder 2 is printed and spaced from the position of the substrate electrode 1a to the printed position within the correction allowable range, It is possible to suppress the solder 2a from spreading on the substrate 3 during the reflow process, and to prevent the adjacent substrate electrode 1a ′ from bridging. Also, the solder 2 sandwiched between the component electrode 3a and the substrate 1 melts and flows toward the electrode 3a, spreads over the entire electrode 1a, provides a self-alignment effect, and is soldered to the correct position.
[Selection] Figure 2

Description

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

In order to manufacture a substrate on which electronic components are mounted (hereinafter referred to as “component mounting substrate”), a printing process in which solder is printed on the electrodes formed on the substrate, so-called substrate electrodes, by a printing device, and the substrate on which the solder is printed On the other hand, a mounting process of mounting a component by the component mounting apparatus and a reflow process of passing the substrate on which the component is mounted in a reflow furnace are executed in this order. Among these processes, in the printing process, the paste solder is placed on the surface of the substrate through the mask opening in a state where the mask in which the opening corresponding to the substrate electrode pattern is formed and the substrate are accurately aligned. Printed on. In this way, in the printing process, the mask is aligned with the substrate, and the positional deviation of the solder with respect to the substrate electrode, that is, the amount of printing deviation is planned to be zero. However, it is very difficult to make the printing misalignment amount zero in the actual printing process.

  By the way, in the reflow process, solder sandwiched between so-called component electrodes such as electrodes and leads formed on the substrate electrode of the substrate and the outer shell of the electronic component melts and flows. At that time, the mounting position of the electronic component may be corrected by a so-called self-alignment effect in which the electronic component moves to the center position side of the substrate electrode due to the solder flow. Therefore, in the invention described in Patent Document 1, for example, the magnitude of the self-alignment effect is determined from the print misalignment state, and the mounting position of the electronic component is switched according to the determination result. More specifically, when the self-alignment effect is large, the electronic component is mounted on the basis of the solder printing position, while when the self-alignment effect is small, the electronic component is mounted on the basis of the electrode position on the substrate.

JP 2007-110170 A (FIGS. 20 and 21)

  In the invention described in Patent Document 1, when the self-alignment effect is small, for example, when the solder is printed out of the electrode formed on the substrate, it is determined that the self-alignment effect is small, and the electrode position on the substrate The electronic parts are mounted on the basis of For this reason, as will be described later, the solder that protrudes from the electrode by the reflow process melts and adheres to the end face of the electronic component, and further wets along the end face to cause a solder defect.

  The present invention has been made in view of the above problems, and by appropriately adjusting the mounting position of the component according to the amount of printing deviation, it is possible to mount the component satisfactorily on the substrate while preventing the occurrence of solder failure. An object is to provide a component mounting apparatus and a component mounting method.

  A component mounting apparatus according to the present invention is a component mounting apparatus for mounting a component on a substrate in which solder is printed on an electrode formed on the substrate, and a head for mounting the component on the substrate in order to achieve the above object. A control unit that controls the operation of the head unit and adjusts the position where the component is mounted in accordance with the amount of printed solder misalignment with respect to the electrode, and the control unit expresses the amount of misaligned printing by melting the solder If the mounting position of the component is within the allowable correction range that can be corrected to the electrode side due to the self-alignment effect, the component is mounted based on the position where the solder is printed, while the amount of misalignment exceeds the allowable correction range The component is mounted on the basis of a predetermined position that is closer to the electrode than the position where the solder is printed and spaced from the position of the electrode toward the printed position within the correction allowable range. It is characterized by a door.

  A component mounting method according to the present invention is a component mounting method for mounting a component on a substrate in which solder is printed on an electrode formed on the substrate, and in order to achieve the above object, the amount of print misalignment of the solder with respect to the electrode The amount of print misalignment, the step of comparing the amount of misalignment with the correction allowable range in which the mounting position of the component can be corrected to the electrode side due to the self-alignment effect expressed by melting of the solder, and the amount of print misalignment is within the allowable range of correction. In some cases, the component is mounted with reference to the position where the solder is printed, while when the amount of printing misalignment exceeds the allowable correction range, it is closer to the electrode than the position where the solder is printed and from the position of the electrode. And a step of mounting a component on the basis of a predetermined position separated from the printed position within the correction allowable range.

  In the invention configured as described above (component mounting apparatus and component mounting method), the position where the component is mounted is adjusted according to the amount of solder printing misalignment with respect to the electrode formed on the substrate. More specifically, when the amount of printing 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-alignment effect, the component is mounted with reference to the position where the solder is printed. In this way, the component is satisfactorily mounted on the substrate by utilizing the self-alignment effect. On the other hand, when the amount of printing deviation exceeds the allowable correction range, that is, when the alignment effect cannot be expected, the printed image is closer to the electrode than the position where the solder is printed and within the correction allowable range from the electrode position. Components are mounted on the basis of a predetermined position separated to the position side. This reduces the amount of solder that spreads toward the adjacent electrodes on the board during reflow processing, and prevents the occurrence of solder defects while mounting components at the correct position based on the board electrode position. Is possible. The details will be described later with reference to specific examples.

  As described above, the position reference for component mounting is adjusted based on whether or not the amount of solder printing misalignment with respect to the electrode is within a correction allowable range in which the mounting position of the component can be corrected to the electrode side due to the self-alignment effect. The component can be mounted at a correct position based on the position of the electrode on the substrate while preventing the occurrence of solder failure.

It is a block diagram which shows the production system of the component mounting board | substrate which mounted components on the board | substrate. It is a figure which shows typically the relationship between the alignment aspect in a component mounting process, and the solder state after a reflow process when the comparatively big printing gap | deviation has generate | occur | produced. It is a schematic diagram which shows the aspect of component mounting according to component information and the amount of printing gaps. It is a schematic diagram which shows the aspect of component mounting according to component information and the amount of printing gaps. It is a top view which shows one Embodiment of the component mounting apparatus concerning this invention. It is a block diagram which shows the main electrical structures of the mounting machine shown in FIG. It is a flowchart which shows the program edit process performed with a printing apparatus before producing a component mounting board. It is a flowchart which shows the program edit process performed with a control apparatus before producing a component mounting board. 6 is a flowchart illustrating a printing process performed by a printing apparatus. It is a flowchart which shows the component mounting process by a mounting machine. It is a flowchart which shows the component mounting process by a mounting machine.

<Relationship between printing misalignment and self-alignment effect>
Before detailed description of the embodiments of the component mounting apparatus and the component mounting method according to the present invention, printing misalignment that occurs in a component mounting board production system generally used in the past will be described and the amount of misprinting will be described. Consider the relationship between the self-alignment effect.

  FIG. 1 is a block diagram showing a production system of a component mounting board in which components are mounted on a board. In this production system, an electrode formed on a substrate, that is, a printing device 10 that prints solder on a so-called substrate electrode, a printing inspection device 20 that inspects a substrate printed by the printing device 10 to obtain a printing displacement amount, A mounting machine (corresponding to the “component mounting apparatus” of the present invention) 30 for mounting components on a printed board and a reflow furnace 40 for performing a reflow process on the board on which the components are mounted are provided. These devices 10, 20, 30, 40 are connected to a local area network LAN. A control device (server PC) 50 that controls the entire production system is connected to the local area network LAN. Various information such as a printing program, a board program, and a printing misalignment amount can be communicated between the control device 50 and each of the devices 10, 20, 30, and 40 via a local area network. In this production system, communication is performed between the control device 50 and each of the devices 10, 20, 30, and 40 by a wired LAN, but the communication method and mode are not limited to this.

  In the production system configured as described above, paste solder is printed on the substrate by the printing apparatus 10 in accordance with the printing program created by the control apparatus 50. That is, in the printing apparatus 10, the substrate carried in by the substrate carrying-in unit is clamped by the substrate moving stage and aligned with a predetermined position directly below the mask, and then solder printing is performed on the substrate. During this solder printing, the solder may be printed out of alignment with the substrate electrode. Therefore, in the production system of FIG. 1, after the printing process and before the mounting process, an inspection is performed by the print inspection apparatus 20, and a printing misalignment amount is obtained for each part mounting part.

  When the amount of printing misalignment is relatively small, the component can be satisfactorily soldered to the substrate electrode by using the self-alignment effect as described in Patent Document 1. In this case, when the component is mounted on the board with the solder printing position as a reference, the solder sandwiched between so-called component electrodes such as electrodes and leads formed on the substrate electrode and the outer shell of the component by reflow processing performed after the mounting processing is performed. It melts and flows, and the component moves to the center position of the substrate electrode by the self-alignment effect. In this way, when the amount of printing misalignment is within the allowable correction range in which the mounting position of the component can be corrected to the substrate electrode side due to the self-alignment effect expressed by the melting of the solder, the component is placed on the board with the solder printing position as a reference It is preferable to implement in.

  On the other hand, when the amount of printing misalignment exceeds the allowable correction range, the following problems may occur when component mounting is performed using the solder printing position as a reference or the board electrode position as a reference. Hereinafter, a case where the component mounting process and the reflow process are performed on the basis of the above will be described by exemplifying a case where the printing misalignment occurs only in the certain direction X.

  FIG. 2 is a diagram schematically showing the relationship between the alignment mode in the component mounting process and the solder state after the reflow process when a relatively large printing deviation occurs. Here, as shown in the figure, the paste-like solder 2 is printed on the substrate electrode 1a formed on the substrate 1 with a deviation of ΔX in the X-axis direction (the thickness of the solder 2 is almost equal to the mask thickness). Although the same H0), but does not reach the adjacent substrate electrode 1a '(ΔXb> 0), the printing deviation amount ΔX in the X-axis direction is relatively large, and the maximum value Xa of the allowable correction range (included in component information described later) The allowable correction value Xa) is exceeded. In this case, for example, as shown in FIG. 5A, the positional shift amount ΔX1 of the component 3 is made the same as the printing misalignment amount ΔX so that the component electrode 3a is matched with the solder printing position of the printing misalignment amount ΔX as a reference. The component 3 is mounted on the substrate 1 by shifting (the thickness of the solder 2 between the component 3 and the substrate 1 is smaller than H0 due to the positive pressure acting on the component 3 when the component 3 is mounted and the weight of the component 3) When the reflow process is performed, a part of the melted solder 2 gets wet on the surface of the substrate electrode 1a and spreads to the left in the figure, and the surface tension of the spread solder 2 tries to draw the component electrode 3a to the left in the figure. Since the amount of printing deviation ΔX is large, the wetting spread of the molten solder does not reach the left end of the substrate electrode 1a and even if the surface tension is applied, the component 3 is kept in the same position until the component electrode 3a completely matches the substrate electrode 1a. Cannot move leftOn the other hand, when the component 3 is mounted on the substrate 1, the thickness of the solder 2 between the component 3 and the substrate 1 becomes smaller than H0, so that the solder 2a that protrudes to the right of the component 3 from the component 3 is melted by the reflow process. Although it tries to spread to the right, it is attracted to the component 3 that moves slightly to the left in the figure, so that it does not reach the adjacent substrate electrode 1a ′ (distance ΔXb> 0 from the solder 2a to the adjacent substrate electrode 1a ′). ). That is, after the reflow process, a solder defect called a solder bridge does not occur, but a mounting position defect that the component 3 cannot be mounted at a correct position with respect to the electrode position of the substrate occurs.

  Further, for example, as shown in FIG. 5B, when the component electrode 3a of the component 3 is mounted on the substrate 1 with the substrate electrode position as a reference and the reflow process is performed, the component 3 is correct with respect to the electrode position of the substrate. Although the mounting position failure that the mounting is not possible at the position does not occur, the following problem occurs. That is, when the substrate electrode position reference is used, when the component 3 is mounted on the substrate 1 to the solder 2 protruding from the substrate electrode 1a in the printed solder 2, the thickness of the solder 2 between the component 3 and the substrate 1 is Due to the fact that it becomes smaller than H0, solder that protrudes from the component 3 to the right side of the figure is added. Thus, the solder 2a protruding from the substrate electrode 1a has almost zero or extremely small area in contact with the component electrode 3a, and most of the solder 2a protruding from the substrate electrode 1a can flow in a free state. . On the other hand, since the component 3 does not move even when the reflow process is performed, the flowable solder 2a does not move to the left in the figure. For this reason, the solder 2a that can flow in a free state reaches the adjacent substrate electrode 1a '. That is, it becomes a solder bridge and a solder failure occurs.

  On the other hand, as shown in FIG. 6C, the amount ΔX1 that is closer to the substrate electrode 1a than the position of the printing displacement amount ΔX on which the solder 2 is printed and that shifts the position of the component 3 when mounted is set as a correction allowable value Xa. When the component 3 is mounted with (= maximum correction allowable range Xa), the solder 2 sandwiched between the substrate electrode 1a and the component electrode 3a is melted in the reflow process and wetted with respect to both the electrodes 1a and 3a. Since the component electrode 3a is drawn to the left by the spread surface tension of the solder 2, the amount of displacement of the component electrode 3a with respect to the substrate electrode 1a is a correction allowable value Xa smaller than FIG. The component 3 moves to the left in the figure until the component electrode 3a of the component 3 completely coincides with the substrate electrode 1a, and after reflow processing, the component 3 can be mounted at a correct position based on the electrode position of the substrate 1. Further, when the component 3 is mounted on the substrate 1 to the solder 2 protruding from the component 3 among the printed solder 2, the thickness of the solder 2 between the component 3 and the substrate 1 is smaller than H0. The solder 2a protruding from the part 3 is formed by adding solder protruding to the right side of the part 3. The solder 2a protruding from the part 3 is melted by the reflow process and further spreads to the right side, but is drawn to the part 3 moving to the left side of the figure. Therefore, since it does not reach the adjacent substrate electrode 1a ′ (ΔXb> 0), a solder failure such as a solder bridge does not occur.

Incidentally, as shown in FIG. 2 (b), solder 2a that protrudes from the component 3 before the reflow process to flow by a reflow process, Ri Do overlapping length of the 'substrate electrode 1a reach the' substrate electrode 1a is a DerutaXc, If the overlap length ΔXc is relatively small , the position of the component electrode 3a relative to the substrate electrode 1a is determined by separating the mounting position of the component 3 from the substrate electrode position reference to a predetermined position exceeding ΔXc within the correction allowable range. Since the shift amount is within a small allowable correction range, the component 3 moves to the left in the drawing until the component electrode 3a of the component 3 completely coincides with the substrate electrode 1a by the reflow process, and the component 3 is referenced to the electrode position of the substrate 1. It can be mounted at the correct position. Since the moving amount of the component 3 exceeds ΔXc, the solder 2a protruding from the component 3 before the reflow process is attracted to the component 3 that moves to the left in the figure in the melted state and is moved to the adjacent substrate electrode 1a ′. Does not reach and does not cause solder bridging.

  In the above, the case where the print misalignment occurs in the X axis direction is considered. However, when the print misalignment occurs in the Y axis direction (direction perpendicular to the paper surface of FIG. 2) perpendicular to the X axis direction, The case where printing misalignment occurs in the two-dimensional plane in the X-axis direction and the Y-axis direction can be considered in the same manner as described above. That is, it is affected by the direction of the component (longitudinal direction (YA direction in FIG. 3) and width direction (XA direction in FIG. 3) in which two component electrodes 3a are arranged).

  In the longitudinal direction in which two component electrodes 3a are arranged (the YA direction in FIG. 3), the surface of the solder 2 that works between the substrate electrode 3a and the component electrode because the solder 2 wets and spreads on the substrate electrode 3a when melted. Since the tension acts at two places, the self-alignment effect is easily obtained, and the allowable correction range is wider than the width direction (XA direction in FIG. 3).

  The correction allowable range is also affected by the size of the component 3. For example, the self-alignment effect is difficult to obtain because the weight of the relatively large component 3 increases. For example, as shown in FIG. 3, a “solder reference flag” indicating whether or not to allow component mounting based on the solder printing position is provided in the component information stored in the control device 50. Is desirable. In addition, as a permissible correction range for each part, an alignment limit value “correction allowable value Xa” of print misalignment in the component direction XA and an alignment limit value “correction allowable value Ya” of misalignment of the print misalignment in the component direction YA are additionally stored in the part information. It is desirable to keep it. That is, the “solder reference flag” in the component information is set to “1” before component mounting, component mounting based on the solder printing position is permitted, and the amount of printing deviation is within the correction allowable range (X-axis direction). In the case where the print misalignment amount ΔX is equal to or smaller than the correction allowable value Xa and the print misalignment amount ΔY in the Y-axis direction is equal to or smaller than the allowable correction value Ya), as shown in FIG. The component mounting position can be corrected using the alignment effect. On the other hand, as shown in FIG. 5B, although the “solder reference flag” is set to “1” and component mounting is permitted based on the solder printing position, the amount of printing deviation exceeds the allowable correction range. If the print misalignment amount ΔY in the Y-axis direction exceeds the allowable correction value Ya in FIG. 7B, component mounting is performed based on the position of the allowable correction range, that is, the position of the allowable correction value Ya. As a result, defective solder can be effectively prevented.

  Further, when the mounting direction to the board 1 is different even though the component 3 is the same, the amount of printing misalignment is caused by making the coordinate system (XA, YA) of the component 3 correspond to the coordinate system (X, Y) of the mounting machine 30. What is necessary is just to determine whether it is in the correction | amendment tolerance. For example, as shown in FIG. 4, when the component 3 is rotated 90 ° and mounted on the substrate 1, whether or not the printing deviation amount ΔX in the X-axis direction is equal to or smaller than the “correction allowable value Ya” of the component 3, Whether or not the alignment effect can be obtained can be determined based on whether or not the printing deviation amount in the direction is equal to or smaller than the “correction allowable value Xa” of the component 3.

  As described above, since the above-described relationship exists between the print misalignment amount and the self-alignment effect, it is determined whether the print misalignment amount is within the correction allowable range, and then the component is determined based on the solder position reference or the allowable position reference. It is desirable to implement. Further, it is desirable that the correction allowable range is optimized according to the type of the component 3 and the mounting direction on the board 1.

  Therefore, in the embodiment described below, component mounting is performed based on the solder position reference or the allowable position reference after determining whether or not the printing deviation amount is within the correction allowable range based on the above consideration. However, in the next embodiment, the print deviation amount is not obtained by the print inspection apparatus 20 but the print deviation amount is obtained based on the correction value detected by the printing apparatus 10. That is, in the embodiment described below, a component mounting board is produced by a production system that does not include the print inspection apparatus 20.

<Embodiment>
FIG. 5 is a plan view showing a mounting machine as an embodiment of the component mounting apparatus according to the present invention. FIG. 6 is a block diagram showing the main electrical configuration of the mounting machine shown in FIG. In this mounting machine 30, a substrate transport mechanism 302 is disposed on a base 311, and the printed substrate 1 on which paste-like solder is printed by the printing apparatus 10 can be transported in a predetermined transport direction X. . More specifically, the substrate transport mechanism 302 has a pair of conveyors 321 and 321 that transport the substrate 1 from the right side to the left side of FIG. Then, the conveyors 321 and 321 carry in the substrate 1, stop it at a predetermined mounting work position (the position of the substrate 1 shown in the figure), and fix and hold the substrate 1 with a holding device (not shown). Then, the electronic component 3 (see FIGS. 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 attached to the head unit 306 recognizes an image of the holding state of the electronic component 3 by the mounting head 361, and the recognition result is output to a controller (control unit) 340 that controls the entire mounting machine 30. The On the other hand, the controller 340 controls the transfer operation based on the image recognition result and the board program, and mounts the electronic component 3 on the board 1 on the basis of the position according to the print displacement amount as will be described later. When the mounting process is completed for all the components to be mounted on the substrate 1, the substrate transport mechanism 302 carries out the substrate 1.

  The component supply unit 304 described above is arranged on the front side (+ Y axis direction side) and the rear side (−Y axis direction side) of the substrate transport mechanism 302 configured as described above. These component supply units 304 include a number of tape feeders 304a. Each tape feeder 304 a is provided with a reel (not shown) around which a tape storing and holding the electronic component 3 is wound, so that the electronic component 3 can be supplied to the head unit 306. That is, on each tape, small chip electronic components 3 such as an integrated circuit (IC), a transistor, and a capacitor are stored and held at predetermined intervals. Then, the tape feeder 304a feeds the tape from the reel to the head unit 306 side, so that the electronic component 3 in the tape is intermittently fed out. As a result, the electronic component 3 can be picked up by the mounting head 361 of the head unit 306. It becomes.

  The head unit 306 transports the electronic component 3 to the substrate 1 while being sucked and held by the mounting head 361 and transfers the electronic component 3 to a position designated by the user. Then, a total of twelve mounting heads 361 including six mounting heads 361F arranged in a line in the X-axis direction on the front side and six mounting heads 361R arranged in a line in the X-axis direction on the rear side are arranged. Have.

  In the head unit 306, six mounting heads 361F extending in the vertical direction Z are provided in a row at an equal pitch in the X-axis direction (the conveyance direction of the substrate 1 by the substrate conveyance mechanism 302). Further, a rear row configured in the same manner as the front row is provided on the rear side (−Y-axis direction side) with respect to the mounting head 361F. That is, six mounting heads 361R extending in the vertical direction Z are provided in a row at an equal pitch in the X-axis direction.

  In addition, a component suction nozzle (not shown) is attached to the tip of each mounting head 361. The negative pressure generator and the same positive pressure generator are connected to each component suction nozzle via an electric switching valve (not shown). It is possible to communicate with either the pressure generation device or the atmosphere, and the controller 340 applies a negative pressure adsorption force from the negative pressure generation device to the component adsorption nozzle, so that the lower end portion (tip portion) of the component adsorption nozzle is provided. ) Attracts the upper surface of the electronic component 3 and can hold the component. Conversely, when the controller 340 supplies positive pressure from the positive pressure generator to the component suction nozzle, the electronic head 3 is released from being held by the mounting head 361, and the electronic component 3 is instantaneously mounted on the substrate 1 by the positive pressure. To do. After the electronic component 3 is mounted, the component suction nozzle is opened to the atmosphere. Thus, in the head unit 306, the electronic component 3 can be attached and detached by controlling the negative pressure adsorption force and the positive pressure supply by the controller 340.

  Each mounting head 361 can be moved up and down (moved in the Z-axis direction) with respect to the head unit 306 by a nozzle lifting / lowering driving mechanism using the Z-axis motor 381 as a driving source, and nozzle rotation using the R-axis motor 382 as a driving source. The drive mechanism can rotate around the central axis of the nozzle. Among these drive mechanisms, the nozzle raising / lowering drive mechanism raises and lowers the mounting head 361 between a lowered position when sucking or mounting and a raised position when carrying or imaging. On the other hand, the nozzle rotation drive mechanism is a mechanism for rotating the component suction nozzle as necessary to match the mounting direction of the electronic component 3 or to correct the suction displacement in the R-axis direction. Thus, the electronic component 3 can be positioned in a predetermined R-axis direction during mounting.

  Further, the head unit 306 transports the electronic component 3 sucked by these mounting heads 361 between the component supply unit 304 and the substrate 1 and mounts it on the substrate 1. It is possible to move in the direction and the Y-axis direction (direction orthogonal to the X-axis and Z-axis directions). That is, the head unit 306 is supported so as to be movable along the X axis with respect to the mounting head support member 363 extending in the X axis direction. Further, both ends of the mounting head support member 363 are supported by a fixed rail 364 in the Y-axis direction, and are movable along the fixed rail 364 in the Y-axis direction. The head unit 306 is driven in the X-axis direction by the X-axis motor 365 via the ball screw 366, and the mounting head support member 363 is driven in the Y-axis direction by the Y-axis motor 367 via the ball screw 368. .

  As described above, the head unit 306 can transport the electronic component 3 attracted by the mounting head 361 from the component supply unit 304 to a target position. In this embodiment, a component recognition camera 307 is attached to the head unit 306 in order to sequentially capture and recognize the suction holding state of the electronic component 3 in the mounting head 361 during component conveyance. In addition to the component recognition camera 307, a board recognition camera 308 is attached to the head unit 306. The substrate recognition camera 308 has a function of recognizing a substrate position and a substrate direction by photographing a plurality of fiducial marks attached to the substrate 1 on the mounting work position. In addition, by moving the head unit 306 above the component supply position of the feeder 304a, it is possible to take an image of the component fed by the feeder 304a by the board recognition camera 308, the component storage portion of the tape, and the like from above.

The mounting machine 30 configured as described above is provided with a controller 340 that controls the entire mounting machine. 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 configured by a CPU or the like, and controls each part of the mounting machine according to a board program stored in advance in the storage unit 342 to perform component mounting based on a position reference corresponding to the amount of printing deviation. The storage unit 342 can store a board program executed by the mounting machine 30. This board program is created by the controller 5 10 of the control device 50 or by another program creation device.

An X-axis motor 365, a Y-axis motor 367, a Z-axis motor 381 and an R-axis motor 382 are electrically connected to the motor control unit 343, and drive control of each motor is performed. Each of the motors 365, 367, 381, and 382 is provided with an encoder (not shown) that outputs a pulse signal corresponding to the rotation state of the motor. The pulse signal output from each encoder is configured to be captured by the controller 340, and the arithmetic processing unit 341 that receives these signals acquires information on the rotation amount of each axis motor 365, 367, 381, 382, by controlling the motors of the respective axes 365,367,381,382 together with the motor control unit 343, the suction nozzle has a configuration that can be moved to any position on the base 3 11.

  In addition, a component recognition camera 307 and a board recognition camera 308 are electrically connected to the image processing unit 344, and imaging signals output from these cameras 307 and 308 are respectively taken into the image processing unit 344. Then, in the image processing unit 344, the analysis of the component image and the analysis of the board image are performed based on the captured imaging signal. As a result, the type, suction status, suction position, and suction direction of the electronic component 3 with respect to the component suction nozzle are image-recognized, the suitability of the electronic component 3 with respect to the suction nozzle, the suction quality, and the suction displacement are detected. Recognize the image. In addition, it is possible to recognize the positional relationship between the component or the component storage unit and the component supply position, thereby detecting a positional deviation of the component relative to the component supply position, or feeding the component to the component supply position. Can be detected.

  In the mounting machine 30, a display / operation unit 350 is provided to display a board program, component information, and the like. The display / operation unit 350 is also used by an operator to input information such as various data and commands to the controller 340. Further, the mounter 30 is provided with a server communication control unit 345 in order to exchange various data such as a board program and component information with the control device 50.

  The control device 50 includes a controller 510 that can create a board program as described above. The controller 510 can create a printing program in addition to the board program, and can control the entire production system. To do. The controller 510 is provided with an arithmetic processing unit 511 configured by a CPU or the like, a storage unit 512 such as a hard disk drive, and a communication control unit 513. Further, the storage unit 512 stores the above-described board program, printing program, component information, and the like. Then, as described below, the production of the component mounting board is executed according to the board program and the printing program. Note that reference numeral 520 in the drawing displays a print program, a board program, component information, and the like created by the arithmetic processing unit 511, and an operator inputs information such as various data and commands to the controller 510. Display / operation unit.

  Next, an operation of producing a component mounting board by a production system (printing apparatus 10 + mounting machine 30 + reflow furnace 40 + control apparatus 50) including the mounting machine 30 configured as described above will be described with reference to FIGS. To do.

  FIG. 7 is a flowchart showing a program editing process executed by the printing apparatus before producing the component mounting board. FIG. 8 is a flowchart showing a program editing process executed by the control device before producing the component mounting board. FIG. 9 is a flowchart showing printing processing by the printing apparatus. Further, FIGS. 10 and 11 are flowcharts showing component mounting processing by the mounting machine.

  When the component mounting board is produced by the production system, a program editing process for adapting to the production of the component mounting board is executed by the printing device 10 and the control device 50 before the production. First, a controller (not shown) provided in the printing apparatus 10 executes a program editing process shown in FIG. That is, this controller edits the printing program by controlling each part of the printing apparatus 10 as follows. First, in step S11, a print program corresponding to the component mounting board among the print programs stored in the storage unit 512 of the control device 50 is read and read into a storage unit (not shown) provided in the controller. In the printing apparatus 10, the mask having an opening corresponding to the electrode pattern formed on the substrate 1 is fixed to the mask holding unit. However, the fixing position may be shifted from a preset position and fixed. is there. Therefore, the fiducial mark attached to the lower surface of the mask is imaged by the mask recognition camera, and the X axis of the printing apparatus 10 corresponding to the X axis direction, the Y axis direction, and the R axis direction of the mounting machine 30 based on the captured image, respectively. The fixed displacement amounts ΔX1, ΔY1, and ΔR1 of the mask in the direction, the Y-axis direction, and the R-axis direction are calculated. In the printing apparatus 10 that moves and aligns the substrate 1 with respect to the fixed mask and prints, the movement amount of the substrate 1 that compensates for the fixed displacement of the mask in this alignment, that is, the “mask fixed displacement correction value” is .DELTA.X1, .DELTA.Y1, .DELTA.R1 which are the same as the fixed displacement of the mask with respect to the X axis direction, Y axis direction and R axis direction. (Step S12).

  Then, the entire mask is imaged by the mask recognition camera (step S13). Since the mask imaging result thus obtained, that is, the entire mask image, includes a fiducial mark and a mask opening, the center position of each mask opening based on the fiducial mark from the mask imaging result. And information such as size is calculated, and these data are stored in the printing program (step S14). When the editing of the printing program is completed in this way, the edited printing program is returned to the storage unit 512 of the control device 50.

  On the other hand, in the control device 50, as shown in FIG. 8, the controller 510 executes the program editing process shown in FIG. That is, the print program edited by the printing apparatus 10 is read from the storage unit 512 into the working memory space, and the board program corresponding to the component mounting board is read out of the board programs stored in the storage unit 512, Is read into the memory space (step S21). Then, the center position and size information of the mask opening corresponding to the component mounting coordinates set in the board program with reference to the fiducial mark of the mask are extracted from the printing program (step S22). Subsequently, offsets ΔX0 and ΔY0 of the mask opening relative to the component mounting coordinates from the component mounting coordinates based on the fiducial mark of the substrate and the position of the mask opening relative to the fiducial mark of the mask. Is calculated. The offsets ΔX0 and ΔY0 resulting from the opening processing error for the mask are stored in association with the mounting coordinates as the mask opening offsets ΔX0 and ΔY0 in the X-axis direction and the Y-axis direction of the mounting machine 30 (step S23). When such processing (steps S22 and S23) is performed on all the mounted coordinates (determined as “YES” in step S24), the board program edited in this way is written in the storage unit 512 (step S25).

  When the editing of the printing program and the board program is thus completed, the printing apparatus 10 reads a desired edited printing program from the storage unit 512 of the control apparatus 50 (step S31), and the controller of the printing apparatus 10 prints the printing apparatus according to the printing program. 10 is controlled to execute the printing process shown in FIG. In this printing apparatus 10, when the substrate 1 on which the electrode pattern is formed is carried into a predetermined substrate fixing position and fixed, the substrate 1 is displaced when the substrate 1 is fixed at the substrate fixing position. Therefore, the fiducial mark of the substrate 1 is imaged by the substrate recognition camera, and the fixed displacement amounts ΔX2, ΔY2, etc. of the substrate 1 in the X-axis direction, the Y-axis direction, and the R-axis direction of the printing apparatus based on the captured image. Find ΔR2. In a printing machine that moves and aligns the substrate 1 with respect to the fixed mask and prints, the movement amount of the substrate 1 in the alignment that compensates for the fixed displacement of the substrate 1, that is, the “substrate fixed displacement correction value” is: It can be calculated as -ΔX2, -ΔY2, and -ΔR2 obtained by reversing the fixed shift amounts ΔX2, ΔY2, and ΔR2 of the substrate 1 with respect to the X-axis direction, the Y-axis direction, and the R-axis direction (step). S32).

  Then, mask fixed displacement correction values ΔX1, ΔY1, ΔR1 and substrate fixed displacement correction values −ΔX2, −ΔY2, and −ΔR2 in the X axis direction, the Y axis direction, and the R axis direction of the printing apparatus 10 set in the printing program. , And misregistration amounts ΔX3, ΔY3, ΔR3 at the time of print alignment stored in the storage unit 512 of the control device 50 (because the substrate 1 is moved and aligned with the mask, the print alignment correction value is ΔX3 , ΔY3, ΔR3 (The initial values when printing on the first substrate 1 are all set to 0 for ΔX3, ΔY3, and ΔR3) to add the substrate 1 to the X-axis direction and the Y-axis direction. The substrate 1 is positioned with respect to the mask so that the fiducial mark on the lower surface of the mask and the fiducial mark on the substrate coincide with each other in the R-axis direction. Simultaneously with the start of positioning of the substrate 1 with respect to the mask, the substrate 1 is raised toward the mask, and the substrate 1 is brought into close contact with the lower surface of the mask in a state where the positioning of the substrate 1 with respect to the mask is completed. Thereafter, paste-like solder is supplied to the upper surface of the mask, and the squeegee is moved in the Y-axis direction while controlling the printing load and moving speed. Thereby, solder is printed on the electrode formed on the substrate 1 through the opening of the mask (step S33).

  Further, in this embodiment, an opening for alignment confirmation is provided in the mask, the substrate 1 after printing is imaged by the substrate recognition camera 1, and the position of the printed solder by the alignment confirmation opening on the substrate 1 is The positional deviation amounts ΔX3, ΔY3, and ΔR3 at the time of printing alignment are obtained, and these are transferred to the controller 340 of the mounting machine 30 through the local area network as printing alignment correction values ΔX3, ΔY3, and ΔR3 (step S34).

  When the printing process for the substrate 1 is completed, the substrate 1 is moved downward and returned to the original position by the amount moved for positioning the substrate 1 with respect to the mask. Then, after the substrate 1 is released, the printed substrate 1 is carried out toward the mounting machine 30 by a substrate transport mechanism such as a conveyor (step S35).

In printed mounter 30 board 1 is sent, select the substrate program in which the controller 340 is stored in the storage unit 342 (step S41), the respective parts of the mounting device 30 has Tsu and its substrate Program The component mounting process shown in FIGS. 10 and 11 is executed under control. The board 1 transported from the printing apparatus 10 is kept waiting at a predetermined standby position, and when the component mounting process is possible in the mounting machine 30, the board transport mechanism 302 waits for a component not mounted. The board | substrate 1 is carried in, it stops at a predetermined mounting operation position (position of the board | substrate 1 shown in FIG. 5), and the board | substrate 1 is fixed and hold | maintained with the holding device which is not illustrated (step S42). Since the positional displacement of the substrate 1 may occur when the substrate is fixed, the fiducial mark of the substrate 1 is imaged by the substrate recognition camera 308, and the X axis direction and the Y axis of the mounting machine 30 are based on the captured image. The fixed displacement amounts ΔX4, ΔY4, ΔR4 of the substrate 1 in the direction and the R-axis direction are calculated as “substrate fixed displacement correction values” (step S43).

  In the next step S44, the offsets ΔX0 and ΔY0 of the mask openings with respect to the mounting coordinates of the parts transferred from the printing apparatus 10 and the positional deviation amounts ΔX3, ΔY3 and ΔR3 at the time of printing alignment are received and the controller 340 Store in the storage unit 342. In this embodiment, the offsets ΔX0 and ΔY0 of the mask openings and the misregistration amounts ΔX3, ΔY3 and ΔR3 at the time of printing alignment are directly transferred from the printing apparatus 10 to the mounting machine 30. The data may be transferred via the storage unit. In this case, the storage unit of the control device 50 sets the offsets ΔX0, ΔY0 of the mask openings and the positional deviation amounts ΔX3, ΔY3, ΔR3 at the time of printing alignment. It functions as a buffer, and the printing apparatus 10 and the mounting machine 30 can transmit and receive offsets ΔX0 and ΔY0 of the respective mask openings and misregistration amounts ΔX3, ΔY3, and ΔR3 at the time of printing alignment at an appropriate timing.

  When the preparation for component mounting is completed in this way, the component information relating to the component belonging to the initial mounting group among the component group to be mounted on the substrate 1 is read from the control device 50 (step S45). This component information is various pieces of information for mounting on the board 1, and as shown in FIGS. 3 and 4, in addition to the component dimensions, the solder reference flag, the correction allowable value Xa of the component direction XA, and the component direction YA YA correction allowable value Ya is included. If component information or the like is already stored in the storage unit 342 at this stage, the information is used.

  In the next step S46, the correction allowable values Xa and Ya set in the component information regarding the components mounted in the current mounting group are read. In the next step S47, the head unit 306 is moved to the component supply unit 304, and the electronic component 3 is sucked by the component suction nozzle mounted on the tip of the mounting head 361. Then, the component recognition camera 307 captures an image of the suction state of the component 3 by the component suction nozzle. Based on the imaging result, suction displacement amounts ΔX5, ΔY5, and ΔR5 in the X-axis direction, the Y-axis direction, and the R-axis direction are obtained. The values −ΔX5, −ΔY5, and −ΔR5 that are reversed in polarity are calculated as “adsorption deviation correction values” (step S48).

  Here, when the head unit 306 is driven and controlled as it is according to the component mounting coordinates Xp, Yp, and Rp set in the substrate program and mounted on the substrate 1, the component adsorption nozzle is affected by the effects of the substrate fixing deviation and the component adsorption deviation. The sucked electronic component 3 is mounted at a position different from the electrode formed on the substrate 1. Accordingly, the fixed displacement correction values ΔX4, ΔY4, ΔR4 calculated in step S43 and the suction displacement correction values -ΔX5, -ΔY5, -ΔR5 calculated in step S48 are added to the component mounting coordinates Xp, Yp, Rp, respectively. Then, the component mounting coordinates Xp, Yp, Rp are corrected (this correction calculation is referred to as “coordinate calculation A”). The lead 3a of the electronic component 3 can be aligned with the electrode 1a formed on the substrate 1 by mounting the component 3 on the component mounting coordinates Xp, Yp, Rp thus corrected. That is, mounting the component 3 on the component mounting coordinates Xp, Yp, Rp obtained by the coordinate calculation A means mounting the component 3 on the substrate 1 based on the electrode position.

  Here, when the solder 2 is accurately printed on the electrode 1a and the amount of printing deviation is zero, it is desirable to mount the component 3 on the component mounting coordinates Xp, Yp, Rp obtained by the coordinate calculation A. However, it is difficult to perform the printing process without causing any printing misalignment. Therefore, in this embodiment, it is determined whether or not component mounting based on the solder printing position is permitted by setting “1” in the “solder reference flag” included in the component information (step S50). . When the determination result is “YES”, that is, when the solder reference flag is ON, a series of processes (steps S51 to S58) described below are executed to further correct the component mounting coordinates Xp, Yp, and Rp. Then, component mounting is executed (step S59). On the other hand, when the determination result is “NO”, that is, the solder reference flag is OFF (“0” is set in the “solder reference flag” of the component information), the coordinate calculation A in step S49 is performed. The component 3 is mounted on the obtained component mounting coordinates Xp, Yp, Rp, that is, the component 3 is mounted on the substrate 1 based on the electrode position (step S59).

In step S51 of the above series of processes, the mask opening is calculated with respect to the calculated coordinates (component mounting positions in the coordinate system set on the base 311 of the mounting machine 30) Xp, Yp, Rp obtained by the coordinate calculation A in step S49. Considering the offsets ΔX0, ΔY0 and misregistration amounts ΔX3, ΔY3, ΔR3 at the time of printing alignment, coordinates (prints related to soldering of corresponding parts in the coordinate system set on the base 311 of the mounting machine 30 are printed. (Center position of solder pattern) Xq, Yq, and Rq are calculated. That is, the following formula: Xq = Xp + ΔX0 + ΔX3
Yq = Yp + ΔY0 + ΔY3
Rq = Rp + ΔR3
To obtain the coordinates Xq, Yq, Rq.

  In step S52, a difference (= ΔX0 + ΔX3) between the X-axis coordinate Xq of the calculated coordinate obtained in step S51 and the X-axis coordinate Xp of the component mounting coordinate obtained in step S49 is obtained, and the absolute value of this difference is set in the component information. It is determined whether or not the correction allowable value Xa is not less than. As described above, in the present embodiment, the amount of printing deviation is obtained by obtaining the difference between the X-axis coordinate Xq and the X-axis coordinate Xp, which exceeds the correction allowable value Xa, that is, the printing deviation is relatively large, and the alignment effect cannot be expected. In the case (see FIG. 2), the component mounting coordinates are corrected by adding the correction allowable value Xa to the X-axis coordinates Xp of the component mounting coordinates obtained in step S49 (subtraction if the difference value is negative) (step S53). ). In this case, by executing step S59 described later, the component 3 is mounted on the substrate 1 on the basis of the allowable position in the X-axis direction as shown in FIG.

  On the other hand, if the printing misalignment amount is equal to or smaller than the allowable correction value Xa, that is, the self-alignment effect is obtained, the X-axis coordinate Xq calculated in step S51 is added to the X-axis coordinate Xp of the component mounting coordinate obtained in step S49. Is rewritten (step S54). In this case, the component 3 is mounted on the substrate 1 on the basis of the solder printing position in the X-axis direction by executing step S59 described later.

Further, in the Y-axis direction, the Y-axis coordinate Yp of the component mounting coordinates is corrected similarly to the X-axis direction (steps S55 to S57). That is, the absolute value of the difference between the Y-axis coordinate Yq of the calculated coordinate obtained in step S51 and the Y-axis coordinate Yp of the component mounting coordinate obtained in step S49, that is, the amount of printing misalignment in the Y-axis direction is greater than the allowable correction value Ya. It is determined whether or not there is (step S55). If the amount of printing misalignment in the Y-axis direction exceeds the allowable correction value Ya, that is, if the printing misalignment is relatively large and the alignment effect cannot be expected, the allowable correction value is added to the Y-axis coordinate Yp of the component mounting coordinates obtained in step S49. Ya is added (subtracted if the difference value is negative) to correct the component mounting coordinates (step S56). On the other hand, when the printing misalignment amount is equal to or less than the allowable correction value Ya, that is, when the self-alignment effect is obtained, the Y-axis coordinate calculated in step S51 is added to the Y-axis coordinate Yp of the component mounting coordinate obtained in step S49. Yq is input and rewritten (step S57).

  The R-axis direction is rewritten by inputting the R-axis coordinate Rq calculated in step S51 to the R-axis coordinate Rp of the component mounting coordinate obtained in step S49 regardless of the amount of printing misalignment (step S58). .

  As described above, when the solder reference flag is set to “1” and the component mounting based on the solder printing position is permitted, the component mounting coordinates corrected in accordance with the printing misalignment amount and the solder reference flag “ If it is set to “0”, the component suction nozzle is moved to the component mounting coordinates calculated in step S49, and then the component sucked and held by the component suction nozzle is mounted on the substrate 1 (step S59). While such component mounting is not completed for all components (determined as “NO” in step S60), information on the next mounting group is read (step S61 in FIG. 10), and then the process returns to step S46 to mount the component. Repeat this step.

  When the mounting of all components onto the substrate 1 is completed, the component-mounted substrate 1 is unloaded from the mounting machine 30 by the substrate transport mechanism 302 (step S62), and reflow processing is performed by the next reflow furnace 40.

  As described above, when the printing misalignment amount is within the allowable correction range (smaller than the allowable correction value Xa in the X-axis direction and smaller than the allowable correction value Ya in the Y-axis direction), the component 3 on the basis of the solder printing position. By performing the reflow process after the component mounting process, the self-alignment effect is effectively expressed, and the component 3 can be mounted on the substrate satisfactorily. If the amount of misalignment exceeds the allowable correction range (greater than the allowable correction value Xa in the X-axis direction and greater than the allowable correction value Ya in the Y-axis direction), and the alignment effect cannot be expected, the allowable limit position (X-axis) Since the component 3 is mounted on the substrate 1 with reference to the position of the allowable correction value Xa in the direction and the position of the allowable correction value Ya in the Y-axis direction, the component 3 is prevented while preventing the occurrence of defective solder as described above. Can be satisfactorily mounted on the substrate 1.

  The present invention is not limited to the above-described embodiment, and various modifications other than those described above can be made without departing from the spirit of the present invention. For example, in the above-described embodiment, the print misregistration amount is calculated in consideration of the mask opening offsets ΔX0 and ΔY0 obtained based on the mask image in addition to the misregistration amounts ΔX3, ΔY3, and ΔR3 at the time of print alignment. The amount of printing misalignment may be obtained considering only the above. Alternatively, the print inspection apparatus 20 may be incorporated in the production system, and the amount of print misalignment detected by the print inspection apparatus 20 may be used. Note that when only the mask opening offsets ΔX0 and ΔY0 obtained based on the mask image are taken into consideration, the printing misalignment amount is obtained, step S34 in FIG. 9 can be omitted, and the camera imaging time and the like can be saved.

  Further, as in the above-described embodiment, when the printing misalignment is greater than or equal to the correction allowable range, the position of the component 3 to be mounted as a component is set as a correction allowable value, or from the substrate electrode position reference to a predetermined position within the correction allowable range By separating, the solder 2 sandwiched between the substrate electrode 1a and the component electrode 3a is melted in the reflow process and wetted with respect to both the electrodes 1a and 3a and spreads to the left in the figure, and the surface tension of the spread solder 2 is increased. Then, the component electrode 3a is pulled to the left in the drawing, and the component 3 moves to the left in the drawing until the component electrode 3a of the component 3 coincides with the substrate electrode 1a. Can be mounted in the correct position. Further, the solder 2a protruding from the part 3 before reflowing is melted by the reflow process and tries to spread further to the right, but is attracted to the part 3 that moves to the left in the figure, so that the adjacent substrate electrode 1a ' Since it does not reach, no solder failure such as a solder bridge occurs.

  In addition, the application target of the present invention is not limited to the mounting machine having the above-described configuration, and can be applied to any component mounting apparatus that mounts components on a board. Further, the component mounting apparatus to which the present invention can be applied is not limited to that incorporated in a production system, and the present invention can also be applied to a mounting machine that operates independently.

DESCRIPTION OF SYMBOLS 1 ... Board | substrate 1a ... Electrode 2 ... Solder 3 ... (Electronic) component 30 ... Mounting machine (component mounting apparatus)
306 ... Head unit 340 ... Controller (control unit)
341 ... arithmetic processing unit (control unit)

Claims (5)

A component mounting apparatus for mounting a component on a substrate having solder printed on electrodes formed on the substrate,
A head unit for mounting the component on the substrate;
A control unit that controls the operation of the head unit and adjusts the position where the component is mounted according to the amount of print misalignment of the solder with respect to the electrode;
The controller is
When the printing misalignment is within a correction allowable range in which the mounting position of the component can be corrected on the electrode side by a self-alignment effect expressed by melting of the solder, the position where the solder is printed is used as a reference. While mounting the component,
When the printing misalignment exceeds the correction allowable range, the solder is closer to the electrode than the position where the solder is printed, and is separated from the position of the electrode toward the printed position within the correction allowable range. A component mounting apparatus for mounting the component on the basis of a predetermined position.   The component mounting apparatus according to claim 1, wherein a position of a correction allowable value that is a maximum value of the correction allowable range is set as the predetermined position.   The component mounting apparatus according to claim 1, wherein the control unit sets the allowable correction range according to a type of the component.   4. The component mounting apparatus according to claim 1, wherein the control unit sets the allowable correction range in accordance with a direction in the component. 5. A component mounting method for mounting a component on a substrate in which solder is printed on an electrode formed on the substrate,
A step of obtaining a printing deviation amount of the solder with respect to the electrode;
Comparing the amount of printing misalignment with a correction allowable range in which the mounting position of the component can be corrected on the electrode side by a self-alignment effect expressed by melting the solder;
When the printing misalignment is within the allowable correction range, the component is mounted on the basis of the position where the solder is printed. On the other hand, when the misprinting amount exceeds the allowable correction range, the solder Mounting the component on the basis of a predetermined position that is closer to the electrode than the printed position and spaced from the electrode position within the correction allowable range toward the printed position. A component mounting method characterized by the above.

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