JP2012146907A - Electronic component mounting method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electronic component mounting method capable of providing a position correction effect by using a proper surface correction data at always, even in the case where a temperature fluctuation occurs because of temporary change in device operation state.SOLUTION: A surface correction data is generated by recognizing a position reference point and each of a plurality of measurement points of a surface correction substrate using a camera. Here, a shaft temperature of a drive shaft which is measured for each drive shaft of a head moving mechanism that moves the camera and a mounting head, and individual displacement data representing a displacement amount from a measurement reference time point at a plurality of measurement points and a position reference point acquired by recognition at the time point, are related each other, and stored as a displacement/temperature correlation data. During the process in which the mounting head is positioned relative to the substrate at the time of a component mounting operation, a position correction amount of the mounting head is calculated based on the displacement amount acquired by recognizing the position reference point and the displacement/temperature correlation data.

Description

  The present invention relates to an electronic component mounting method for mounting an electronic component on a substrate.

  An electronic component mounting apparatus that picks up an electronic component from a component supply unit with a mounting head and mounts the electronic component on a substrate generally includes a camera for substrate recognition, and detects the position of the substrate by imaging the substrate with this camera. Based on the detection result, alignment at the time of component mounting is performed. The position of the optical system coordinates of the substrate recognition camera is not necessarily at the position indicated on the control data, and a positional shift occurs due to various factors. This positional deviation is not necessarily uniform due to the mechanism error of the moving mechanism for moving the camera, and indicates a specific positional deviation amount at each position in the mounting area to be mounted with the electronic component. For this reason, there is known an electronic component mounting apparatus having a function of performing so-called surface correction for obtaining these specific positional deviation amounts for each position in the mounting area (see, for example, Patent Document 1).

  In the prior art disclosed in this patent document, as a calibration method for surface correction, a calibration substrate in which measurement points are provided in a lattice shape is used, and a positional deviation amount is previously measured for each measurement point. The position error is obtained as a unique position error, and the position correction is performed by the position error unique to each mounting point during the mounting operation.

JP 2002-9495 A

  However, in the prior art including the above-mentioned patent document examples, the following problems have occurred due to the calibration execution timing for surface correction. That is, a precision driving mechanism such as a linear motor or a ball screw drive is used as a moving mechanism for moving a mounting head or a camera in an electronic component mounting apparatus. A complicated driving error is caused by the temperature change. For this reason, even if calibration is performed at a specific point in time and surface correction data is acquired, if temperature fluctuations occur due to changes in the operating state of the device over time, the surface correction data is no longer appropriate and effective position correction is performed. It was difficult to obtain an effect.

  Therefore, the present invention provides an electronic component mounting method that can always obtain an effective position correction effect using appropriate surface correction data even when temperature fluctuations occur due to changes in the operating state of the apparatus over time. The purpose is to do.

  In the electronic component mounting method of the present invention, the substrate positioned and held by the substrate holding unit is imaged with a substrate recognition camera to recognize the position, and the mounting head is moved by the head moving mechanism to take out the electronic component from the component supply unit. An electronic component mounting method for mounting the electronic component on the substrate by positioning the mounting head with respect to the substrate based on the result of the position recognition, for surface correction in which a plurality of measurement points are formed in a lattice shape The substrate is held by the substrate holding unit, and the camera is moved by the head moving mechanism, and the position is measured by sequentially imaging the plurality of measurement points and the position reference points where the positional relationship with the substrate holding unit is fixed. In addition, a position measurement step for acquiring individual displacement data indicating a displacement amount from a position at the measurement reference time for each drive shaft constituting the head moving mechanism, and the position measurement step are set in advance. In the process of repeatedly executing a plurality of times at a given timing, the shaft temperature measured as a representative temperature representatively indicating the temperature state of the drive shaft at the time point for each drive shaft and the individual displacement data acquired at the time point In the process of positioning the mounting head with respect to the substrate, the displacement / temperature correlation data storage step for storing the position reference point and the plurality of measurement points in the storage unit as displacement / temperature correlation data A position correction calculation step of calculating a position correction amount of the mounting head based on the displacement / temperature correlation data, and controlling the head moving mechanism by adding the position correction amount to the result of the position recognition, thereby controlling the mounting head. And a mounting execution step of mounting an electronic component by positioning with respect to the substrate.

  According to the present invention, a camera for recognizing a substrate and a head moving mechanism for moving a mounting head when generating surface correction data by recognizing a plurality of measurement points and position reference points of the surface correction substrate with a camera. For each drive shaft, the shaft temperature measured as the representative temperature at that time of the drive shaft is associated with the position reference point acquired at that time and the individual displacement data of a plurality of measurement points, and the position reference as displacement / temperature correlation data By storing the point and multiple measurement points in the storage unit and calculating the position correction amount of the mounting head based on the displacement / temperature correlation data in the process of positioning the mounting head with respect to the substrate during component mounting work Therefore, even when temperature fluctuations occur due to changes in the operating status of the equipment over time, an effective position correction effect is always obtained using appropriate surface correction data. Rukoto can.

The top view of the electronic component mounting apparatus of one embodiment of this invention Explanatory drawing of a structure and function of the mounting head in the electronic component mounting apparatus of one embodiment of this invention Explanatory drawing of the head movement mechanism and the surface correction board | substrate in the electronic component mounting apparatus of one embodiment of this invention The block diagram which shows the structure of the control system of the electronic component mounting apparatus of one embodiment of this invention Explanatory drawing of the displacement and temperature correlation data used for surface correction in the electronic component mounting method of one embodiment of the present invention The flowchart which shows the electronic component mounting process of one embodiment of this invention Explanatory drawing of the position measurement process in the component mounting method of one embodiment of this invention Explanatory drawing of the displacement and temperature correlation data of the position reference point in the electronic component mounting method of one embodiment of this invention, and the measurement point of the surface correction board | substrate The flowchart which shows the position correction amount calculation process in the electronic component mounting process of one embodiment of this invention Process explanatory drawing of the position correction amount calculation process in the electronic component mounting process of one embodiment of this invention

  First, the structure of the electronic component mounting apparatus 1 will be described with reference to FIGS. In FIG. 1, a substrate transport mechanism 2 is disposed in the center of the base 1a in the X direction (substrate transport direction). The substrate transport mechanism 2 transports the substrate 4 delivered from the upstream device, and positions and holds the substrate 4 at the mounting position by the substrate holder 3 provided in the transport path. A component supply unit 5 is disposed on both sides of the substrate transport mechanism 2, and a plurality of tape feeders 6 are arranged in parallel on the component supply unit 5. The tape feeder 6 feeds the electronic component to a take-out position by a mounting head described below by pitch-feeding a carrier tape holding the electronic component to be mounted.

  A Y-axis movement table 7 is provided on each of both ends of the upper surface of the base 1a, and two X-axis movement tables 8 are installed on the Y-axis movement table 7 so as to correspond to the respective component supply units 5. Has been. Each X-axis moving table 8 is equipped with a mounting head 10 and a substrate recognition camera 12 that moves integrally with the mounting head 10. The Y-axis moving table 7 and the X-axis moving table 8 constitute a head moving mechanism 9. By driving the head moving mechanism 9, the mounting head 10 and the substrate recognition camera 12 move horizontally in the X direction and the Y direction.

  As shown in FIG. 2, the mounting head 10 is a multiple head including a plurality of unit transfer heads 11 that hold one electronic component P, and each unit transfer head 11 is vacuum-sucked with the electronic component P. The suction nozzle 11a that is held by the above is provided. By driving a nozzle lifting mechanism (not shown) built in each unit transfer head 11, the suction nozzle 11a is lifted and lowered individually. Further, by driving the nozzle θ-axis motor 10a provided in common to the mounting head 10, the rotation mechanism of each unit transfer head 11 can be driven to rotate each suction nozzle 11a around the nozzle axis.

  By driving the head moving mechanism 9, the mounting head 10 sucks and takes out the electronic component P from the tape feeder 6 of the component supply unit 5 by the suction nozzle 11 a of each unit transfer head 11, and FIG. As shown in (b), the electronic component P is mounted on the mounting point on the upper surface of the substrate 4. Further, by moving the mounting head 10 above the substrate transport mechanism 2, the substrate recognition camera 12 also moves with the mounting head 10, and the mark posts 15 set on the upper surface of the substrate 4 and in the vicinity of the substrate 4 by the substrate recognition camera 12 are moved. The position can be detected by imaging. As a result, as shown in FIGS. 2B and 2A, the positional deviation amount between the optical origin OP of the imaging visual field 12a and the position detection target mark M (see the measurement point 41 and the position reference point 15a shown in FIG. 3). ΔX and ΔY can be detected.

  A component recognition camera 13 and a nozzle stocker 14 are disposed between the substrate transport mechanism 2 and the component supply unit 5. The mounting head 10 that has picked up the electronic component from the component supply unit 5 by the unit transfer head 11 moves above the component recognition camera 13, so that the component recognition camera 13 is held by the unit transfer head 11. Image P from below. The imaging results of the substrate recognition camera 12 and the component recognition camera 13 are subjected to recognition processing by a recognition processing unit 25 (see FIG. 4), thereby recognizing the position of the component mounting point on the substrate 4 and the electronic state held by the mounting head 10. The position recognition of the component P is performed, and in the component mounting operation of the electronic component P on the board 4, position correction at the time of component mounting is performed based on these position recognition results. In the nozzle stocker 14, suction nozzles 11 a mounted on the unit transfer head 11 are stored and held corresponding to a plurality of component types. In the component mounting operation, the mounting head 10 is accessed to the nozzle stocker 14 to execute the nozzle replacement operation, whereby the suction nozzle 11a mounted on the unit transfer head 11 is replaced according to the component type to be mounted. can do.

  Next, a surface correction data acquisition function provided in the electronic component mounting apparatus 1 will be described with reference to FIG. In the substrate recognition by the substrate recognition camera 12, the substrate recognition camera 12 at the time of imaging is caused by the drive error due to the temperature change of the Y-axis movement table 7 and the X-axis movement table 8 which are the drive axes constituting the head moving mechanism 9. A position shift occurs, and an error occurs in the position recognition result. This error is not necessarily uniform within the movement region of the substrate recognition camera 12 by the head moving mechanism 9, and indicates a unique position error at each position within the region. Such a position error is due to thermal expansion and contraction of each drive mechanism due to a change in temperature of the drive shaft, and thus is not uniform in time series, and also shows a different behavior depending on a change in temperature over time.

  For this reason, in the electronic component mounting apparatus 1 shown in the present embodiment, for so-called surface correction for correcting a specific position error at the time of imaging by the board recognition camera 12 at each position in the moving region by the head moving mechanism 9. Is obtained in a form corresponding to the temperature change with time of each drive shaft constituting the head moving mechanism 9. Hereinafter, a configuration provided in the electronic component mounting apparatus 1 in order to acquire surface correction data corresponding to such a temperature change with time will be described.

  As shown in FIG. 3, the Y-axis moving table 7 and the X-axis moving table 8 which are drive shafts constituting the head moving mechanism 9 include driving motors 7M and 8M, respectively. During the work operation of continuously driving the Y-axis moving table 7 and the X-axis moving table 8, the Y-axis moving table 7 and X are caused by various heat rise factors such as heat generation of the motors 7M and 8M themselves and frictional heat of the shaft driving mechanism. The axis movement table 8 increases in temperature as the operating time elapses. Due to the thermal deformation of the shaft drive mechanism due to this temperature change, an error occurs in the positional accuracy in the horizontal movement of the substrate recognition camera 12. Furthermore, the thermal deformation also affects the accuracy of the mounting posture of the board recognition camera 12, and the imaging optical axis of the board recognition camera 12 that should be in the vertical state tends to be slightly inclined from the vertical axis. . For this reason, the position of the imaging optical axis of the substrate recognition camera 12 on the upper surface of the substrate 4 to be imaged is shifted from the original position by an amount corresponding to an inclination, and an error occurs in position recognition by imaging.

  The error in the position recognition result due to the positional accuracy in the horizontal movement of the substrate recognition camera 12 and the inclination of the imaging optical axis is due to the temperature change of the Y-axis movement table 7 and the X-axis movement table 8 over time. In the present embodiment, the surface correction data that has been acquired in a fixed manner in the prior art can be acquired in a form associated with the temperature change of the Y-axis movement table 7 and the X-axis movement table 8 over time. The electronic component mounting apparatus 1 is configured.

  That is, in the electronic component mounting apparatus 1, temperature measurement points 7a and 8a are set in the vicinity of the motors 7M and 8M of the Y-axis moving table 7 and the X-axis moving table 8 constituting the head moving mechanism 9, and the X-axis is respectively set. The table temperature sensor S1 and the Y axis table temperature sensor S2 are arranged so that the temperature data of the temperature measurement points 7a and 8a can be acquired as the axis temperature of the Y axis movement table 7 and the X axis movement table 8 at an arbitrary timing. ing. The temperature measurement results obtained by the X-axis table temperature sensor S1 and the Y-axis table temperature sensor S2 are representative of the temperature states of the Y-axis movement table 7 and the X-axis movement table 8 that are drive axes constituting the head movement mechanism 9. It has the character as temperature (shaft temperature).

  The temperature measurement points 7a and 8a at which the X-axis table temperature sensor S1 and the Y-axis table temperature sensor S2 are disposed are set in the vicinity of the motors 7M and 8M here, but the temperature state of the drive shaft is representative. The temperature measurement points 7a and 8a may be appropriately selected as other positions as long as the positions are determined to be appropriate as the representative temperature measurement points shown. Of course, the representative temperature may be defined by a calculation process such as obtaining an average temperature based on temperatures measured at a plurality of locations. Then, the surface correction data is acquired in the form in which the shaft temperature measured in this way is associated with the individual displacement data described below.

  Here, the surface correction substrate 40 used for surface correction data acquisition will be described. As shown in FIG. 3B, the surface correction board 40 is a dummy board used as a dummy of the board 4 to be mounted with components, and has the same outer diameter as that of the board 4. On the upper surface of the surface correction substrate 40, measurement points 41 to be used for measuring the amount of positional deviation are formed in a grid arrangement with pitches px and py in the X direction and Y direction, respectively. At the time of surface correction data acquisition, as shown in FIG. 3A, the surface correction substrate 40 is held by the substrate holder 3 of the substrate transport mechanism 2, and in this state, the substrate recognition camera 12 is placed on the surface correction substrate 40. It moves, and each measurement point 41 is imaged with the board | substrate recognition camera 12 sequentially.

  At this time, the position reference point 15 a of the mark post 15 provided on the base 1 a with the positional relationship with the substrate holding unit 3 fixed in the vicinity of one outside of the substrate transport mechanism 2 is also measured together with the measurement point 41 and the substrate recognition camera 12. Is imaged. The absolute position of the mark post 15 in the horizontal direction is fixed in the electronic component mounting apparatus 1, and the position reference point 15a is used as a position reference point that does not change in the horizontal position in the process of component mounting work.

  Next, the configuration of the control system will be described with reference to FIG. The control unit 20 is an arithmetic device, and controls various units described below by executing various programs and data stored in the storage unit 21 to execute component mounting work and various arithmetic processes. The storage unit 21 stores mounting data 22 such as mounting coordinate data necessary for causing each unit to perform component mounting work, and displacement / temperature correlation data 23. The displacement / temperature correlation data 23 is surface correction data for correcting a position detection error of the substrate recognition camera 12 caused by a temperature change with time of the Y-axis movement table 7 and the X-axis movement table 8. The position measurement result executed at a predetermined timing for the correction substrate 40 is created by associating it with the axis temperatures of the Y-axis movement table 7 and the X-axis movement table 8. In the component mounting operation, the control unit 20 refers to the displacement / temperature correlation data 23 to calculate a position correction amount when the mounting head 10 is aligned with the substrate 4.

  The mechanism driving unit 24 drives the substrate transport mechanism 2, the X-axis movement table 8, the Y-axis movement table 7, and the mounting head 10 under the control of the control unit 20. Thereby, the board | substrate conveyance operation | movement which conveys and positions the board | substrate 4, and the component mounting operation | movement which mounts the electronic component P picked out from the component supply part 5 on the board | substrate 4 are performed. The recognition processing unit 25 performs recognition processing on the imaging results obtained by the component recognition camera 13 and the board recognition camera 12. Thereby, the position recognition of the component mounting point of the board | substrate 4 and the position recognition of the electronic component P in the state hold | maintained at the mounting head 10 are performed. The displacement detection unit 26 detects the position of the measurement point 41 and the position reference point 15a from the imaging result obtained by imaging the measurement point 41 of the surface correction substrate 40 and the position reference point 15a of the mark post 15 by the substrate recognition camera 12, and performs measurement. Processing for obtaining individual displacement data indicating the amount of displacement of the position from the measurement reference time set at the start is performed.

  The shaft temperature detector 27 detects the shaft temperatures of the Y-axis movement table 7 and the X-axis movement table 8 from the measurement output data of the X-axis table temperature sensor S1 and the Y-axis table temperature sensor S2. The surface correction data creation processing unit 28 includes the shaft temperature detected by the shaft temperature detection unit 27 and the individual displacement data detected by the displacement detection unit 26, that is, the positions of the measurement points 41 and the mark posts 15 on the surface correction substrate 40. A process of creating displacement / temperature correlation data is performed by associating the displacement of the reference point 15a from the measurement reference time point. The created displacement / temperature correlation data 23 is stored in the storage unit 21.

  A specific example of the displacement / temperature correlation data 23 stored in the storage unit 21 will be described with reference to FIG. This displacement / temperature correlation data is a simulated operation in which the mounting head 10 is reciprocated between the component supply unit 5 and the substrate 4 by the head moving mechanism 9 without actually mounting the component on the substrate in the electronic component mounting apparatus 1. Is obtained in the course of an aging operation that repeatedly executes. That is, in this process, the shaft temperature indicating the temperature state of the Y-axis movement table 7 and the X-axis movement table 8 gradually increases, and the arrival position at which the substrate recognition camera 12 moves slightly varies with this temperature change. Due to the variation of the arrival position, a positional deviation also occurs in the result of the position recognition by imaging the measurement point 41 and the position reference point 15a by the substrate recognition camera 12. Since this displacement amount is considered to depend on the temperature state of the Y-axis movement table 7 and the X-axis movement table 8, the displacement detection unit 26 detects the displacement amount in the aging operation in which the above-described simulation operation is repeatedly executed. And the shaft temperature detection by the shaft temperature detector 27 are executed in synchronization with each other at a predetermined interval. Then, the surface temperature data and the displacement amount obtained in synchronization are correlated by the surface correction data creation processing unit 28, thereby creating the displacement / temperature correlation data 23.

  FIG. 5 shows a data table DT in which the displacement / temperature correlation data 23 obtained in this way is displayed as a graph. Here, the horizontal axis represents the shaft temperature (° C.), the vertical axis represents the displacement amounts ΔX and ΔY (displacement amount μm from the measurement reference point), and the X-axis direction displacement amount ΔX and the X-axis table shaft temperature (X-axis table). The graph showing the correlation with the temperature measurement point 7a detected by the temperature sensor S1 is a solid curve L (X), the displacement amount ΔY in the Y-axis direction and the Y-axis table axis temperature (Y-axis table temperature sensor). A graph showing a correlation with the temperature of the temperature measurement point 8a detected by S2 is indicated by a dashed curve L (Y).

  In the graph showing the displacement / temperature correlation data 23, the position recognition by the substrate recognition camera 12 in a state where the temperatures of the Y-axis movement table 7 and the X-axis movement table 8 are increased to the axis temperatures by designating the axis temperature. Can be estimated. Also, by specifying the displacement amount, it is possible to estimate the shaft temperatures of the Y-axis movement table 7 and the X-axis movement table 8 in a state where the displacement amount of the position recognition by the substrate recognition camera 12 becomes the displacement amount.

  Next, the electronic component mounting process flow in the component mounting method of the present invention will be described with reference to FIG. In this component mounting method, the substrate 4 positioned and held by the substrate holding unit 3 is imaged by the substrate recognition camera 12 to recognize the position, the mounting head 10 is moved by the head moving mechanism 9, and the electronic component P is transferred from the component supply unit 5. The electronic component P is mounted on the substrate 4 by positioning the mounting head 10 with respect to the substrate 4 based on the result of position recognition by the substrate recognition camera 12.

  In FIG. 6, first, the surface correction substrate 40 on which a plurality of measurement points 41 are formed in a lattice shape is held by the substrate holding unit 3 (ST1). Next, the substrate recognition camera 12 is moved above the substrate 4 and the mark post 15 by the head moving mechanism 9, and as shown in FIGS. 7A and 7B, the plurality of measurement points 41 and the substrate holding unit 3 are connected. The position reference point 15a on the mark post 15 whose positional relationship is fixed is sequentially imaged (ST2) (see the imaging order indicated by arrows a, b, c, d, and e). Then, the displacement detection unit 26 measures the positions of these measurement points 41 and the position reference point 15a, and the individual displacement data indicating the amount of displacement from the position at the measurement reference point is used as a drive shaft constituting the head moving mechanism 9. Obtained for each axis movement table 7 and X-axis movement table 8 (ST3) (position measurement step).

  The above-described position measurement process is repeatedly performed a plurality of times at a preset timing in the process of an aging operation in which a simulation operation for reciprocating the mounting head 10 between the component supply unit 5 and the substrate 4 is repeatedly performed. In this process, the displacement / temperature correlation data is obtained by associating the shaft temperature of the drive shaft with the individual displacement data acquired at the time point for each drive shaft (ST4). Here, the shaft temperature measured as a representative temperature representatively indicating the temperature state of the drive shaft at the time point by the shaft temperature detection unit 27 and the individual displacement data acquired by the displacement detection unit 26 at the time point Surface correction data is created by associating with the correction data creation processing unit 28 and stored in the storage unit 21 for each of the position reference point 15a and the plurality of measurement points 41 (ST5) (displacement / temperature correlation data storage step).

  That is, as shown in FIG. 8, each measurement point 41 set on the surface correction substrate 40 corresponds to each of the measurement points 41 (1), (2), (3)... (I). The data tables DT (1), (2), (3)... (I)... Are created in the same manner as the data table DT of the displacement / temperature correlation data 23 shown in FIG. Similarly, a data table DT (BP) corresponding to the position reference point 15a on the upper surface is created.

  Thereafter, when the component mounting operation is started, the mounting head 10 is moved between the component supply unit 5 and the substrate 4 by the head moving mechanism 9, and the electronic component P taken out from the component supply unit 5 is transferred to the substrate 4. The component mounting operation to be mounted is repeatedly executed. In this component mounting operation, the position of the component mounting point on the board 4 is recognized by moving the board recognition camera 12 together with the mounting head 10 by the head moving mechanism 9, and the mounting head 10 is moved based on the position recognition result. Position with respect to the substrate 4. For this reason, in the component mounting operation, an error occurs in the position recognition result due to the temporal change of the temperature state of the Y-axis movement table 7 and the X-axis movement table 8 constituting the head movement mechanism 9.

  In order to correct this error, in the process of positioning the mounting head 10 with respect to the substrate 4, the position correction amount of the mounting head 10 is calculated based on the displacement / temperature correlation data 23 stored in the storage unit 21 (ST6). (Position correction calculation process). Then, the head moving mechanism 9 is controlled by adding the position correction amount based on the displacement / temperature correlation data 23 to the result of position recognition by the board recognition camera 12, thereby positioning the mounting head 10 with respect to the board 4. The component P is mounted (ST7) (mounting execution process).

  Next, the details of the above-described position correction calculation process will be described with reference to FIGS. In the position correction calculation step, first, the position reference point 15a is imaged by the substrate recognition camera 12, and individual displacement data of the position reference point 15a at that time is obtained (ST11). That is, as shown in FIG. 10A, the substrate recognition camera 12 is moved above the mark post 15, and the imaging result obtained by imaging the position reference point 15 a is detected by the displacement detection unit 26. Displacement amounts ΔX * and ΔY * of the position reference point 15a from the measurement reference point are obtained.

  Next, the shaft temperatures corresponding to the displacement amounts ΔX * and ΔY *, which are individual displacement data obtained, are obtained from the displacement / temperature correlation data 23 for each drive shaft. That is, as shown in FIG. 10B, in the data table DT (BP) which is the displacement / temperature correlation data 23 for the position reference point 15a, the shaft temperatures Tx and Ty respectively corresponding to the displacement amounts ΔX * and ΔY *. Is obtained from the curves L (X) and L (Y). In order to obtain the position correction amount corresponding to the shaft temperatures Tx and Ty, the mounting point MP of the board 4 that is the target in the component mounting operation among the displacement / temperature correlation data 23 stored in the storage unit 21. In addition, the data table DT (i) corresponding to the measurement point 41 (i) having the closest XY coordinate position in the component mounting area is referred to.

  That is, as shown in FIG. 10C, in the data table DT (i), displacement amounts ΔX (i) and ΔY (i) corresponding to the shaft temperatures Tx and Ty are indicated by the displacement / temperature correlation data 23. Obtained from the curves L (X) and L (Y). Then, the obtained displacement amounts ΔX (i) and ΔY (i) are set as position correction amounts in the component mounting operation for the mounting point MP. Thereby, even when the temperature states of the Y-axis moving table 7 and the X-axis moving table 8 constituting the head moving mechanism 9 are fluctuating with time, the temperature depends on the temperature state at the time when the component mounting operation is executed. In addition, the mounting position of the mounting head 10 to the substrate 4 can be adjusted in consideration of the appropriate position correction amount.

  In the above example, in the process of performing the component mounting operation, the position of the position reference point 15a is recognized by the board recognition camera 12, so that the shaft temperature is obtained via the data table DT (BP) included in the displacement / temperature correlation data 23. Tx and Ty are estimated, but the shaft temperature is directly obtained by the X-axis table temperature sensor S1 and the Y-axis table temperature sensor S2 disposed at the temperature measurement points 7a and 8a, and the displacement corresponding to the shaft temperature is obtained. The amounts ΔX (i) and ΔY (i) may be used as position correction amounts.

  As described above, the component mounting method shown in the present embodiment creates surface correction data by recognizing the measurement points 41 and the position reference points 15a of the surface correction substrate 40 by the substrate recognition camera 12. At this time, for each drive axis of the board recognition camera 12 for recognizing the board 4 and the head moving mechanism 9 for moving the mounting head 10, an axis temperature measured as a representative temperature representatively indicating a temperature state at the time of the drive axis The individual displacement data acquired for each measurement point 41 and the position reference point 15a at the time point is associated with each other, and the displacement / temperature correlation data 23 is stored in the storage unit 21 for each position reference point 15a and each measurement point 41. In the process of positioning the mounting head 10 with respect to the substrate 4 during component mounting work, the position of the mounting head 10 is determined based on the displacement / temperature correlation data 23. It is obtained by employing the method of calculating the correction amount. As a result, even when temperature fluctuations occur due to changes in the operating state of the apparatus over time, an effective position correction effect can always be obtained using appropriate surface correction data.

  The electronic component mounting method of the present invention has an effect that an effective position correction effect can always be obtained using appropriate surface correction data even when a temperature variation occurs due to a change in the operating state of the apparatus over time. And can be used in a field where a component is transferred and mounted on a substrate by a mounting head.

DESCRIPTION OF SYMBOLS 1 Electronic component mounting apparatus 3 Board | substrate holding part 4 Board | substrate 5 Component supply part 7 Y-axis movement table 7a, 8a Temperature measurement point 8 X-axis movement table 9 Head movement mechanism 10 Mounting head 11a Adsorption nozzle 12 Substrate recognition camera 15a Position reference point 40 Surface correction board 41 Measurement point M mark MP Mounting point DT Data table ΔX, ΔY Displacement

Claims (2)

Based on the result of the position recognition, the board positioned and held on the board holding part is imaged with a camera for board recognition to recognize the position, the mounting head is moved by the head moving mechanism and the electronic component is taken out from the component supply part. An electronic component mounting method for mounting an electronic component on a substrate by positioning the mounting head with respect to the substrate,
A substrate for surface correction in which a plurality of measurement points are formed in a lattice shape is held by the substrate holding unit, and the camera is moved by the head moving mechanism so that the positional relationship between the plurality of measurement points and the substrate holding unit is A position measuring step of sequentially imaging fixed position reference points to measure the position, and acquiring individual displacement data indicating the amount of displacement from the position at the measurement reference time for each drive axis constituting the head moving mechanism;
In the process of repeatedly performing the position measurement step a plurality of times at a preset timing, the shaft temperature measured as a representative temperature representatively indicating the temperature state of the drive shaft at the time point for each drive shaft and the time point Displacement / temperature correlation data storage step for associating the acquired individual displacement data and storing the position reference point and a plurality of measurement points in a storage unit as displacement / temperature correlation data;
In the process of positioning the mounting head with respect to the substrate, a position correction calculation step of calculating a position correction amount of the mounting head based on the displacement / temperature correlation data;
And a mounting execution step of mounting the electronic component by positioning the mounting head with respect to the substrate by controlling the head moving mechanism by adding the position correction amount to the position recognition result. Electronic component mounting method.   In the position correction calculation step, first, the position reference point is imaged by the camera to obtain the individual displacement data at the time point, and then the shaft temperature corresponding to the obtained individual displacement data is determined for each of the drive axes. Obtained from the temperature correlation data, further obtained individual displacement data corresponding to the obtained shaft temperature from the displacement / temperature correlation data for each drive shaft, and the displacement amount indicated in the obtained individual displacement data as a position correction amount. The electronic component mounting method according to claim 1, wherein:

Images