JP2007227492A - Electronic component mounter and mounting method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electronic component mounter and mounting method in which suction holding state of an electronic component can be judged accurately and efficiently. <P>SOLUTION: In the electronic component mounter for taking out an electronic component from a component feeding section by vacuum suction and mounting it on a substrate using a mounting head equipped with a suction nozzle, suction state after the electronic component is taken out from the component feeding section by the mounting head is inspected by judging the suction state based on the vacuum pressure in the vacuum suction path from the suction nozzle, or by judging the holding state through component recognition for imaging the electronic component held by the suction nozzle based on data prestored in a data library, and the judgment is used properly depending on the objective electronic component and the aptitude of the suction nozzle. Consequently, suction holding state of the electronic component can be judged accurately and efficiently. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an electronic component mounting apparatus and an electronic component mounting method for taking out an electronic component from a component supply unit with a mounting head and mounting the electronic component on a substrate.

  In an electronic component mounting apparatus that mounts electronic components on a substrate, a component mounting operation in which the electronic components are taken out from the component supply unit by the mounting head and transferred to the substrate is repeatedly executed. As a method for holding the electronic component by the mounting head, a method by vacuum suction is frequently used. In this method, the electronic component is held by using the negative pressure generated by vacuum suction from the suction hole in a state where the suction nozzle having the suction hole provided at the lower end is in contact with the upper surface of the electronic component. There is an advantage that the holding state can be controlled only by turning on / off the vacuum suction, but the suction holding state is not necessarily stable because the vacuum suction state changes depending on various factors, and the electronic parts are securely held and held. There is a drawback that release is not guaranteed.

For this reason, in the electronic component mounting apparatus using the suction nozzle that holds the electronic component by vacuum suction, after a pickup operation for taking out the electronic component by moving the suction nozzle up and down by the component supply unit, for example, at a predetermined timing of the mounting operation, It is confirmed whether or not the electronic component is normally sucked and held. Conventionally, as a method for inspecting the suction holding state of the electronic component, a method of detecting the degree of vacuum of a vacuum suction circuit (see, for example, Patent Document 1), or the presence or absence of an electronic component at the lower end of the suction nozzle is used to detect an object by an optical sensor And a method of determining by image recognition using a camera (see, for example, Patent Document 2).
JP-A 64-86088 JP-A-62-199322

  However, the determination of the suction holding state of the electronic component by the above method has the following difficulties. First, in the method of detecting the degree of vacuum in the suction nozzle, it is difficult to determine the suction state due to the use of a small diameter nozzle having a small suction hole diameter when a minute part is targeted. That is, since the pressure loss at the time of vacuum suction is large in the small-diameter nozzle, there is no great difference between the degree of vacuum in the suction nozzle when the chip is sucked and the degree of vacuum when the chip is not sucked. . In comparison with the suction capacity of the suction means for vacuum suction of the suction nozzle, the amount of suction air sucked from the narrow suction hole in the absence of electronic components and the suction of electronic components with the electronic components held by suction This is because there is no significant difference between the amount of suction air sucked due to leakage with the nozzle.

  In addition, if the suction holding state determination is performed by detecting the presence / absence of electronic parts using image recognition, the suction nozzle must be moved to the imaging position by the camera every time inspection is performed, and the movement time of the mounting head increases, which increases the operating efficiency. It is against the request for improvement. As described above, the electronic component suction holding state determination in the conventional electronic component mounting apparatus has a problem that it is difficult to perform accurate determination efficiently.

  Accordingly, an object of the present invention is to provide an electronic component mounting apparatus and an electronic component mounting method capable of accurately and efficiently performing the determination of an electronic component suction holding state.

An electronic component mounting apparatus according to the present invention is an electronic component mounting apparatus that takes out an electronic component from a component supply unit by vacuum suction using a mounting head equipped with a suction nozzle, and mounts the electronic component on a substrate. A suction state determination means for determining a suction state of an electronic component in the suction nozzle by detecting a vacuum pressure inside;

  Holding state determination means for optically recognizing an electronic component held by the mounting head to determine a holding state of the electronic component in the suction nozzle, component data on the electronic component, and a nozzle on the suction nozzle A data library for storing a plurality of types of data, and whether the suction state determination unit or the holding state determination unit determines whether the component suction holding state is correct after the electronic component is taken out from the component supply unit by the suction nozzle. And an inspection method determination unit for determining based on the component data and / or nozzle data.

  The electronic component mounting method of the present invention detects a vacuum pressure in a suction head that vacuum-sucks the suction nozzle, and a mounting head that vacuum-sucks the electronic component from a component supply unit by suction suction using a suction nozzle, and transfers and mounts it on a substrate. A suction state determination means for determining the suction state of the electronic component by the above, and a holding state determination for optically recognizing the electronic component held by the mounting head to determine the holding state of the electronic component in the suction nozzle An electronic component mounting method for mounting different electronic components on a board by an electronic component mounting apparatus comprising means and a data library storing a plurality of types of component data for the electronic component and nozzle data for the suction nozzle, respectively, Pre-judgment judgment of the component suction holding state after the electronic component is taken out from the component supply unit by the suction nozzle Whether it carried out in one of the adsorption state determining means and the holding state determining means is determined based on the component data and or nozzle data.

  According to the present invention, whether the suction holding state after the electronic component is taken out from the component supply unit by the mounting head is determined by the suction state determining unit based on the vacuum pressure or the holding state determining unit based on the component recognition. By making a decision based on the component data and / or nozzle data and using them appropriately according to the suitability of the target electronic component and the suction nozzle, it is possible to accurately and efficiently determine the suction holding state of the electronic component.

  Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a plan view of an electronic component mounting apparatus according to an embodiment of the present invention. FIG. 2 is a functional explanatory diagram of the configuration and holding state determination of the mounting head in the electronic component mounting apparatus according to an embodiment of the present invention. FIG. 4 is a functional explanatory diagram of the configuration of the unit mounting head and the suction state determination in the electronic component mounting apparatus according to the embodiment of the present invention, and FIG. 4 shows the configuration of the control system of the electronic component mounting apparatus according to the embodiment of the present invention. FIG. 5 is an explanatory diagram of a data library in the electronic component mounting apparatus according to the embodiment of the present invention, and FIG. 6 is a flowchart showing the electronic component mounting method according to the embodiment of the present invention.

  First, the configuration of the electronic component mounting apparatus will be described with reference to FIG. 1, FIG. 2, and FIG. In FIG. 1, a transport path 2 is disposed in the center of the base 1 in the X direction (substrate transport direction). The conveyance path 2 conveys the substrate 3 carried in from the upstream side and positions it on the mounting stage. On both sides of the conveyance path 2, component supply units 4 are arranged, and each component supply unit 4 has a plurality of tape feeders 5 arranged in parallel. The tape feeder 5 feeds a component to a component suction position by a suction nozzle of a mounting head described below by pitch-feeding a carrier tape holding an electronic component (hereinafter simply abbreviated as “component”).

Y-axis tables 6A and 6B are disposed on both ends of the upper surface of the base 1, and two X-axis tables 7A and 7B are installed on the Y-axis tables 6A and 6B. By driving the Y-axis table 6A, the X-axis table 7A moves horizontally in the Y direction, and by driving the Y-axis table 6B, the X-axis table 7B moves horizontally in the Y direction. Mounted on the X-axis tables 7A and 7B are a mounting head 8 and a substrate recognition camera 9 that moves integrally with the mounting head 8, respectively.

  By driving the Y-axis table 6A, the X-axis table 7A, the Y-axis table 6B, and the X-axis table 7B in combination, the mounting head 8 moves horizontally. As a result, the mounting head 8 takes out the components from the respective component supply units 4, transports and mounts the components on the substrate 3 positioned in the transport path 2. The Y-axis table 6A, the X-axis table 7A, the Y-axis table 6B, and the X-axis table 7B serve as a head moving mechanism that moves the mounting head 8. The substrate recognition camera 9 moved onto the substrate 3 together with the mounting head 8 by the head moving mechanism captures and recognizes the substrate 3.

  As shown in FIG. 2A, the mounting head 8 is a multiple head having a plurality of unit mounting heads 8a, and each unit mounting head 8a has a suction nozzle 12 for vacuum-sucking and holding a component 13. It is installed. Each unit mounting head 8a includes a nozzle raising / lowering mechanism for raising and lowering the suction nozzle 12 and a nozzle rotating mechanism for rotating the suction nozzle 12 about its axis.

  A component imaging unit 10 and a nozzle holding unit 11 are disposed on the path from the component supply unit 4 to the conveyance path 2. The component imaging unit 10 includes an illumination unit 14 and a component recognition camera 15 as shown in FIG. The nozzle holding unit 11 stores a plurality of types of suction nozzles 12 in a predetermined posture, and the mounting head 8 accesses the nozzle holding unit 11 to perform a nozzle replacement operation. The nozzle is replaced accordingly. In the present embodiment, since the component mounting operation is performed for a plurality of types of components, the nozzle holding unit 11 stores a plurality of types of suction nozzles 12 corresponding to these component types.

  When the mounting head 8 that has taken out components from the component supply unit 4 by vacuum suction moves to the substrate 3 positioned on the mounting stage of the conveyance path 2, the component 13 held by the suction nozzle 12 is moved above the component imaging unit 10. 2, the component recognition camera 15 acquires an image of the component P held by the suction nozzle 12 as shown in FIG.

  The component recognition camera 15 is connected to the recognition processing unit 16, and the recognition processing unit 16 recognizes the image data acquired by the component recognition camera 15, so that the component holding state at the lower end of the suction nozzle 12, that is, That is, it is possible to acquire data for detecting the presence / absence of a component and misalignment. The recognition result is sent to the holding state determination unit 24c (see also FIG. 4), and thereby, the holding state of the component in the suction nozzle 12, that is, the presence / absence of the component and the displacement state are determined. Accordingly, the component imaging unit 10, the recognition processing unit 16, and the holding state determination unit 24 c optically recognize the component held by the mounting head 8 to determine the holding state of the component in the suction nozzle 12. It is a state determination means.

  As shown in FIG. 3, the suction nozzle 12 is detachably mounted on a nozzle mounting portion 8b provided on the unit mounting head 8a. A suction passage 13 is connected to the nozzle mounting portion 8b, and the suction passage 13 communicates with a suction hole provided in the suction nozzle 12 in a state where the suction nozzle 12 is attached. The intake passage 13 is connected to a vacuum pump 19 via a valve 18 for suction on / off. By opening and closing the valve 18 with the vacuum pump 19 driven, on / off of vacuum suction from the suction nozzle 12 is controlled. Is done.

A vacuum pressure sensor 17 is connected to the intake passage 13, and the vacuum pressure sensor 17 detects the vacuum pressure in the intake passage 13. The detection result is transmitted to the suction state determination unit 24b (see also FIG. 4), thereby determining the suction state in the suction nozzle 12. That is, in the state where the suction nozzle 12 normally sucks and holds the component, the suction hole of the suction nozzle 12 is almost closed by the suction holding surface of the component, so that the vacuum pressure ( The absolute value of the negative pressure increases.

  On the other hand, even if the vacuum pump 19 is driven in a state where no component is held by the suction nozzle 12, air is sucked from the suction hole of the suction nozzle 12, so that the vacuum pressure in the intake passage 13 is kept low. do not do. Even when the component is held by the suction nozzle 12, the vacuum in the above-described correct holding state is also caused by the vacuum leak even when the position is greatly displaced and the suction hole is partially in communication with the outside. The pressure is not reached.

  In such a case, the component is held by the suction nozzle, but its holding state is unstable, causing a large positional shift during the component mounting operation, or even falling off the holding state. May cause problems. If the mounting operation is continued while leaving such a defect, a mounting error or a machine trouble occurs. Therefore, after the mounting head 8 takes out the component from the component supply unit 4, the component suction state by the suction nozzle 12 is as early as possible. It is necessary to judge correctness.

  In the present embodiment, immediately after the pickup operation of the suction nozzle 12 picking up and holding the component by the component supply unit 4, first, the correctness of the component suction state is determined by detecting the vacuum pressure in the suction path 13. I try to judge. That is, a threshold that can stably separate the vacuum pressure in the suction path 13 in the above-described correct suction holding state and the vacuum pressure in a state where no part is present or the part is largely displaced beyond the allowable range. The value Vth is set in advance for each nozzle type of the suction nozzle 12. Then, during actual work operation, the vacuum pressure measured by the vacuum degree sensor 17 is compared with this threshold value vth.

  That is, as shown in FIG. 3B, if the measurement result of the vacuum pressure sensor 17 exceeds a predetermined threshold value Vth, the component is sucked and held in a normal state by the suction nozzle 12, If the threshold value Vth is not satisfied, it can be determined that the component is not held in the suction nozzle 12 or is held in an abnormal state such as a large displacement. The determination process based on the threshold value Vth is performed by the suction state determination unit 24b. Accordingly, the vacuum pressure sensor 17 and the suction state determination unit 24b serve as a suction state determination unit that determines the suction state of the components in the suction nozzle 12 by detecting the vacuum pressure in the suction passage that vacuum-sucks the suction nozzle 12. Yes. In the present embodiment, this method that can be determined immediately after the pickup operation by the suction nozzle is preferentially applied.

  Next, the configuration of the control system of the component mounting apparatus will be described with reference to FIG. The control unit 20 performs overall control of each unit described below. The storage unit 21 stores a program necessary for operation control of each unit of the component mounting apparatus and various data. These data include a parts library 21a, a nozzle library 21b, and a combination library 21c.

  The parts library 21a is a part number, shape type, size, and usable nozzle type for a plurality of types of parts such as parts P1, P2, and P3 shown in FIG. Etc. are edited as a data library. The component P1 is a component having a relatively large size D1 having a connection bump 22a on the lower surface side such as a BGA. The component P2 is a rectangular small chip component having a minute size D2, and the suction holding surface 22b is not a perfect plane, and has a characteristic that it easily causes a vacuum leak when sucked and held by the suction nozzle 12. . The third component P3 is a deformed component having a large shape such as a connector and having a concave portion such as a groove 22c provided in the outer shape, and similarly, a vacuum leak inevitably occurs when suctioned by the suction nozzle 12.

The nozzle library 21b can hold the nozzle number, shape type, and suction holding of the suction nozzles 12 that can be used in the unit mounting head 8a of the component mounting apparatus, for example, the suction nozzles 12A, 12B, and 12C shown in FIG. Data such as component types are edited in a library format. The suction nozzle 12A is a small-diameter nozzle having a small diameter d1 corresponding to a small component (for example, the component P2) having a small suction holding surface, and the suction nozzle 12B is intended for a normal size component having a relatively large suction holding surface. This is a standard diameter nozzle having a diameter d2 larger than d1. Further, the suction nozzle 12C includes a block-like suction portion 23 so that a large component can be held by a wide suction holding surface.

  The combination library 21c stores component-nozzle combination data as shown in FIG. The part-nozzle combination data is data indicating a classification of the suction holding inspection method selected in advance based on the difficulty level of the suction state detection when the part shown in the part library 22a is held by the suction nozzle 12 shown in the nozzle library 22b. Are compiled and edited.

  Therefore, the storage unit 21 is a data library that stores a plurality of types of component data for components to be mounted and nozzle data for suction nozzles, and further stores the combination library data described above. When performing mounting work for multiple types of components using the same electronic component mounting device, refer to the data library with such a configuration to find an appropriate suction state detection method corresponding to each component suction nozzle. You can choose.

  That is, when the component P1 is targeted, the suction nozzle 12C having a large suction surface is selected as the compatible nozzle, and in this case, the classification V (suction state detection based on vacuum pressure) is set in advance. On the other hand, when the component P2 is targeted, even if the suction nozzle 12A suitable for this type is sucked and held, the component P2 has a vacuum leak between the suction holding surface and the suction surface of the suction nozzle as described above. It is easy to occur, and there is no big difference in the vacuum pressure between the state where the parts are normally sucked and held by the suction nozzle 12 and the case where no parts are present, and it is difficult to determine the suction holding state based on the measured vacuum pressure.

  Further, when the suction nozzle 12C is used for the component P3, the same problem arises due to a vacuum leak due to the presence of the groove 22c on the suction holding surface of the component 3. Therefore, when adopting a combination having a high degree of difficulty in detecting the suction state based on the vacuum pressure, the category R (holding state detection by component recognition) is applied. As a result, a stable determination result can be obtained in determining whether the component suction holding state is correct. That is, when this section R is applied, the determination of the holding state of the component is also performed at the time of component recognition without performing the suction state determination based on the vacuum pressure.

  In the present embodiment, in addition to the parts library 21a and the nozzle library 21b, the component-nozzle combination data shown in FIG. 5C is created in advance and stored in the storage unit 21 as the combination library 21c. Although an example is shown, only the parts library 21a and the nozzle library 21b are stored, and the classification of the method used for the suction holding correct / incorrect determination is determined by the function of the suction holding correct / incorrect determination unit 24 described below. May be. In addition, when the nozzle type or the component type to be applied is limited, the above-described division R / V may be fixed and allocated in advance for each component or each nozzle type.

The suction holding correct / incorrect determination unit 24 has a function of determining whether or not the suction holding state of the component in each suction nozzle 12 of the mounting head 8 that has picked up the component from the component supply unit 4 is correct. The state determination unit 24b and the holding state determination unit 24c are configured. The inspection method determination unit 24a determines whether or not the suction holding state is correct by referring to the suction state determination unit 24b described below.
It has a function of determining which one of the holding state determination units 24c performs.

  This inspection method determination is determined based on the difficulty level of the suction state detection determined by any one of the parts library 21a and the nozzle library 21b stored in the storage unit 21 as described above, or a combination of these data. . That is, the inspection method determination unit 24a determines whether the suction state determination unit or the holding state determination unit determines the correctness of the suction holding state of the component after the component is taken out from the component supply unit 4 by the suction nozzle 12. The determination is made based on the component data and / or nozzle data stored in the storage unit 21. This determination is made based on the difficulty level of component suction state detection determined for the combination of component data and nozzle data.

  The recognition processing unit 16 has a function of recognizing the imaging result of the component recognition camera 15, and the holding state determination unit 24 c performs the component holding state in the suction nozzle 12 based on the recognition result, that is, the presence / absence and position of the component. It is determined whether or not the degree of deviation is within an allowable range. The head moving mechanism 25 is a Y-axis table 6A, 6B and an X-axis table 7A, 7B that move the mounting head 8, and its operation is controlled by the control unit 20. The Z-axis drive unit 26 and the Θ-axis drive unit 27 drive the nozzle lifting / lowering mechanism and the nozzle rotation mechanism of each unit mounting head 8a provided in the mounting head 8, and each control of the operation is similarly performed by the control unit 20. Is called.

  Next, with reference to FIG. 6, the electronic component mounting method performed using this electronic component mounting apparatus is demonstrated. When the component mounting operation is started, first, the mounting head 8 moves to the component suction position of the component supply unit 4 (ST1). Next, component suction by the mounting head 8 is performed (ST2). That is, the suction nozzles 12 mounted on the unit mounting heads 8a of the mounting head 8 are sequentially aligned with the parts feeder 5 that stores the components to be mounted, and the suction nozzle 12 is lowered to remove the components by vacuum suction. Pick-up operation to hold and take out.

  At this timing, the inspection method determination unit 24a performs the inspection method determination based on the combination of the type of the suction nozzle 12 mounted on the mounting head 8 and the type of the component extracted in the pickup operation (ST3). ). That is, in the combination library 21c, it is set in advance whether the suction state determination unit or the holding state determination unit determines whether the suction state is correct after the part is taken out from the part supply unit 4 by the suction nozzle 12. Based on the classification data, the inspection method determination unit 24a determines the determination.

  Here, if it is determined that the suction state determination based on the classification V, that is, the degree of vacuum should be applied, the components in the suction nozzle 12 by the suction state determination unit 24 b based on the vacuum pressure measured by the vacuum pressure sensor 17. Is determined (ST4). If it is determined here that the suction state NG (there is no part or there is a positional deviation exceeding the allowable range), the pickup operation by the suction nozzle 12 is executed again. In other words, when there is a positional deviation, after the component with the positional deviation is dropped and collected, if there is no part, the component suction of (ST2) is executed again. If it is determined in (ST4) that the suction state is OK (there is a component and the positional deviation is less than the allowable range), the mounting head 8 is moved to a recognition position by the component imaging unit 10 (ST5) Execute component recognition for the purpose of deviation detection. In other words, the component image acquired by the component recognition camera 15 is recognized to detect the positional deviation of the component.

On the other hand, if it is determined in (ST3) that the classification R, that is, the holding state determination by component recognition should be applied, the process proceeds to (ST5) without executing (ST4), and the presence / absence of a component is determined. For the purpose of both determination and misregistration detection, holding state determination by component recognition is executed (ST6). If it is determined here that there is no component, the mounting head 8 is moved to the suction position of the component supply unit 4, and each step after (ST2) is executed again. If it is determined in (ST6) that there is a component, the position deviation detection of the component is also executed at the same time. Then, in the process of moving the mounting head 8 to the mounting position, a position correcting operation is executed based on the amount of positional deviation detected in (ST6) (ST7), and the component is mounted on the mounting point of the board 3. (ST8).

  As described above, according to the present invention, whether or not the suction holding state is correct after the component is taken out from the component supply unit 4 by the mounting head 8 is determined based on the suction state determination unit based on the measured vacuum pressure and the holding state determination unit based on the component recognition. It is determined based on component data and / or nozzle data. Thereby, these can be properly used according to the suitability of the target component and the suction nozzle, and the suction holding state determination of the component can be performed accurately and efficiently.

  The component mounting apparatus and the component mounting method of the present invention have an effect that the suction holding state of the component can be accurately and efficiently performed, and the component is taken out from the component supply unit by vacuum suction by the mounting head having the suction nozzle. It can be used for transfer and mounting on a substrate.

The top view of the component mounting apparatus of one embodiment of this invention Functional explanatory diagram of configuration and holding state determination of mounting head in component mounting apparatus according to one embodiment of the present invention Functional explanatory diagram of unit mounting head configuration and suction state determination in the component mounting apparatus of one embodiment of the present invention The block diagram which shows the structure of the control system of the component mounting apparatus of one embodiment of this invention Explanatory drawing of the data library in the component mounting apparatus of one embodiment of this invention The flowchart which shows the component mounting method of one embodiment of this invention

Explanation of symbols

3 Substrate 4 Component supply unit 8 Mount head 8a Unit transfer head 12, 12A, 12B, 12C Suction nozzle 13 Intake passage 15 Component recognition camera 17 Vacuum pressure sensor P, P1, P2, P3 Component

Claims (4)

An electronic component mounting apparatus that takes out an electronic component from a component supply unit by vacuum suction using a mounting head equipped with a suction nozzle and mounts it on a substrate,
A suction state determination means for determining a suction state of an electronic component in the suction nozzle by detecting a vacuum pressure in an intake passage for vacuum suction of the suction nozzle;
Holding state determination means for optically recognizing the electronic component held by the mounting head to determine the holding state of the electronic component in the suction nozzle;
A data library storing a plurality of types of component data for the electronic component and nozzle data for the suction nozzle;
Based on the component data and / or nozzle data, whether the suction state determination unit or the holding state determination unit determines whether the component suction holding state is correct after the electronic component is taken out from the component supply unit by the suction nozzle. An electronic component mounting apparatus comprising an inspection method determination unit for determining.   The electronic component mounting apparatus, wherein the inspection method determination unit performs the determination based on a detection difficulty level of a component suction state determined for a combination of the component data and nozzle data. Judgment status of electronic components is determined by detecting the vacuum pressure in the intake head that vacuum-sucks the suction nozzle and the mounting head that vacuum-sucks and picks up the electronic component from the component supply unit. A holding state determining unit that determines the holding state of the electronic component in the suction nozzle by optically recognizing the electronic component held by the mounting head, and a component for the electronic component An electronic component mounting method for mounting different electronic components on a board by an electronic component mounting apparatus including a data library storing a plurality of types of data and nozzle data for suction nozzles,
Based on the component data and / or nozzle data, whether the suction state determination unit or the holding state determination unit determines whether the component suction holding state is correct after the electronic component is taken out from the component supply unit by the suction nozzle. An electronic component mounting method characterized by determining. The electronic component mounting method according to claim 1, wherein the determination is performed based on a detection difficulty level of a component suction state determined for a combination of the component data and nozzle data.

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