JP3770072B2 - Electronic component mounting method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an electronic component mounting method for transferring and mounting an electronic component on a substrate.
[0002]
[Prior art]
The electronic component mounting apparatus moves the transfer head above the electronic component supply unit, causes the nozzle provided in the transfer head to move down and up, and vacuum-sucks the electronic component to the lower end of the nozzle. Then, the transfer head is moved upward above the substrate, and the nozzle is lowered and raised again to mount the electronic component at a predetermined coordinate position on the substrate.
[0003]
As described above, when the electronic component is picked up by causing the nozzle to move down / up, if the lowering stroke is too large, the lower end of the nozzle strongly presses the upper surface of the electronic component to destroy the electronic component. If the lowering stroke is too small, the nozzle cannot land on the upper surface of the electronic component, and the electronic component cannot be properly picked up, resulting in a pickup error. Therefore, the lowering stroke of the nozzle must be optimally controlled.
[0004]
In recent years, miniaturization of electronic components has progressed, and the accuracy required for nozzle lowering stroke control has become higher. For example, when targeting microchip components, the lowering stroke is controlled within an extremely narrow error range of about 0.05 mm. Is required. Such chip parts are generally supplied in a taping state, and a tape holding electronic parts by a plurality of tape feeders arranged in the electronic part supply section is pitch-fed to a pickup position by a transfer head.
[0005]
[Problems to be solved by the invention]
However, since the pick-up position of the electronic component in the tape feeder is structurally overhanging from the base portion on which the tape feeder is placed, the height position tends to vary, and the height position of many tape feeders is set as described above. It is very difficult to install within the tolerance range. For this reason, in the conventional electronic component mounting method, there is a problem that when picking up a minute component, problems such as a suction error or damage to the electronic component are likely to occur during pick-up.
[0006]
Accordingly, an object of the present invention is to provide an electronic component mounting method that can prevent pickup mistakes and damage to electronic components.
[0007]
[Means for Solving the Problems]
The electronic component mounting method of the present invention is an electronic component mounting method in which an electronic component held on a tape is picked up by a suction nozzle of a transfer head and mounted on a substrate, and the tape is supplied to a pickup position by the transfer head. A step of mounting a dummy jig of the tape feeder on a feeder base on which the tape feeder is mounted, and a height of a height detection point set on the dummy jig corresponding to the electronic component pickup position of the tape feeder Mounting a height position detecting means for detecting a position on a fixed part of the electronic component mounting apparatus; detecting a height position of the height detection point by the height position detecting means; and detecting the height position A step of storing the result in the storage unit of the electronic component mounting apparatus, and a process for obtaining the component height position of the electronic component based on the stored height position detection result Then, the electronic component held on the tape is vacuum-sucked by the suction nozzle to be picked up by the suction nozzle and picked up on the substrate positioned on the positioning unit by controlling the descending stroke of the transfer head based on the data of the component height position. Mounting process.
[0008]
According to the present invention, the height position of the height detection point set in correspondence with the electronic component pickup position of the tape feeder is detected by the height position detection means on the dummy jig of the tape feeder mounted on the feeder base. By determining the height position of the electronic component based on the detection result of the height position, it is possible to appropriately control the descending stroke of the transfer head when picking up the electronic component, such as picking up error or damage to the electronic component. Problems can be prevented.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Next, embodiments of the present invention will be described with reference to the drawings. 1 is a plan view of an electronic component mounting apparatus according to an embodiment of the present invention, FIG. 2 is a side view of the electronic component mounting apparatus according to an embodiment of the present invention, and FIG. 3 is an electronic circuit according to an embodiment of the present invention. FIG. 4 is an explanatory diagram of tape feeder height detection of the electronic component mounting apparatus according to the embodiment of the present invention.
[0010]
First, the structure of the electronic component mounting apparatus will be described with reference to FIGS. In FIG. 1, a large number of tape feeders 2 for supplying electronic components are arranged in parallel in the electronic component supply unit 1. The tape feeder 2 is mounted on the feeder base 1b (see FIGS. 2 and 4), and moves in the lateral direction by driving the feed screw 3 to rotate.
[0011]
A rotary head 4 is disposed on the front side of the supply unit 1. The rotary head 4 rotates index around the main shaft O, and a plurality of transfer heads 5 are provided on the circumference thereof. As shown in FIG. 2, the transfer head 5 includes a plurality of suction nozzles 5 a, and the transfer head 5 moves up and down while being located at the pickup position P of the electronic component. The electronic component is picked up and picked up from the pickup position 2a by the suction nozzle 5a.
[0012]
In this electronic component pick-up operation, the feed screw 3 is rotationally driven by a motor (not shown) to move the tape feeder 2 containing a desired electronic component to the pick-up position P. The transfer head 5 is rotated around its axis by a rotation mechanism (not shown), and a plurality of suction nozzles 5a provided on the circumference are selected, and the horizontal direction of the electronic component vacuum-sucked at the lower end of the suction nozzle 5a is selected. Set the angle in the rotation direction.
[0013]
The lifting / lowering operation of the transfer head 5 can be stopped at an arbitrary height position by digital control. Thus, during the pickup operation, the pickup height can be individually set according to the pickup position 2a of each tape feeder 2.
[0014]
The electronic component picked up at the pickup position P moves in the direction of arrow a shown in FIG. 1 by the index rotation of the rotary head 4 and reaches the recognition station 7. In the recognition station 7, the electronic component held by the suction nozzle 5a is imaged by the camera from below. Then, by performing image processing on the image data obtained by the imaging, the electronic component is recognized and the positional deviation is detected.
[0015]
The front side of the rotary head 4 is a positioning portion for the substrate 9, and a movable table 10 for positioning the substrate 9 is disposed in the positioning portion. The transfer head 5 moved from the recognition station 7 reaches the mounting position M on the substrate 9 and moves up and down there to mount the electronic component held by the suction nozzle 5 a on the substrate 9.
[0016]
Next, the control system will be described with reference to FIG. In FIG. 3, a control unit 20 is a CPU, and controls the operation and arithmetic processing of the entire electronic component mounting apparatus. The program storage unit 21 stores various programs necessary for electronic component mounting operation and arithmetic processing. The mounting data storage unit 22 stores mounting coordinate data indicating the position of the mounting point of the electronic component to be mounted and mounting data such as component data.
[0017]
The feeder height storage unit 23 stores the height position of the pickup position 2 a of the tape feeder 2 for each tape feeder 2. As will be described later, the height position data is obtained by attaching a removable height detection unit 27 (height position detection means) to a fixed portion around the supply unit 1 on which the tape feeder 2 is arranged. It is acquired by measuring a predetermined part of the dummy jig of the tape feeder attached to 1b. The mechanism drive unit 24 drives mechanism units such as the rotary head 4 and the movable table 10. The image recognition unit 25 recognizes image data obtained by imaging an electronic component at the recognition station 7 and performs identification and position detection of the electronic component. The data capturing unit 26 captures the height position data detected by the height detection unit 27 and stores it in the feeder height storage unit 23.
[0018]
This electronic component mounting apparatus is configured as described above, and tape feeder height detection by this electronic component mounting apparatus will be described below with reference to FIG. When the product type is switched in the electronic component mounting operation, the supply unit 1 performs the rearrangement to replace the tape feeder 2 corresponding to the new board on the feeder base 1b. Since the tape feeder 2 is mounted in a form in which the pickup position 2a by the transfer head 5 is overhanged from the feeder base 1b, the height position of the pickup position 2a in the mounted state depends on variations in planar accuracy of the feeder base 1b. The height position is not necessarily adapted to the pickup operation by the transfer head 5.
[0019]
Therefore, the variation in the planar accuracy of the feeder base 1b is obtained in advance, and the suction height correction is performed to correct the suction height by the suction nozzle 5a of the transfer head 5 by this variation during the pickup operation. Hereinafter, a method for acquiring correction data for correcting the suction height will be described. First, as shown in FIG. 4, a dummy jig 2 ′ is mounted on the feeder base 1b. The dummy jig 2 ′ has a shape similar to that of the tape feeder 2, and a height detection point 2 ′ a is set at a position corresponding to the pickup position 2 a of the tape feeder 2. The dummy jig 2 'has a shape accuracy set so that the height position of the height detection point 2'a accurately corresponds to the height position of the electronic component at the pickup position 2a in the state of being mounted on the feeder base 1b. ing.
[0020]
Next, a displacement sensor 27a is mounted via a bracket 28 on a fixed portion around the supply unit 1 in which a large number of tape feeders 2 are arranged. At this time, the detection target point of the displacement sensor 27a is aligned with the height detection point 2′a of the dummy jig 2 ′. The displacement sensor 27a is connected to the detection unit 27b, and the detection unit 27b obtains height position data of the height detection point 2′a based on the detection signal of the displacement sensor 27a. That is, the distance from the reference height position of the displacement sensor 27a to the height detection point 2′a of the dummy jig 2 ′ is obtained, and the height position data obtained by converting this distance into the height position on the machine coordinate system is obtained. Desired. The displacement sensor 27 a and the detection unit 27 b constitute a height detection unit 27.
[0021]
In the feeder height detection, the detection unit 27b is connected to the data capturing unit 26 (see FIG. 3) of the electronic component mounting apparatus. Then, the height position of the height detection point 2'a at the position corresponding to each tape feeder 2 is detected while sequentially moving the dummy jig 2 'mounted on the feeder base 1b. The detected feeder height data (height position detection result) is stored in the feeder height data storage unit 23 via the data capturing unit 26.
[0022]
In detecting the height of the feeder, a dummy jig 2 'may be mounted at a position corresponding to each tape feeder on the feeder base 1b to obtain the height position of each tape feeder. The tape feeder to be detected may be set by extraction, and the feeder height data of another tape feeder located in the middle may be obtained from these height measurement data by interpolation.
[0023]
The feeder height data obtained and stored in this way is read out by the control unit 20, and the control unit 20 determines the height position of the electronic component at the pickup position 2a of each tape feeder 2 based on the feeder height data. Is calculated. During the mounting operation, the descending stroke of the transfer head 5 is controlled based on the height data of the electronic component thus obtained. As a result, when the electronic component is picked up by the suction nozzle 5a, the gap between the lower end of the suction nozzle 5a and the upper surface of the electronic component located at the pickup position 2a is always kept at an appropriate gap.
[0024]
Therefore, even when targeting a small chip that requires a high degree of suction position accuracy at the time of pick-up, a suction error caused by suction from the suction nozzle 5a with an excessive gap or pressing of the suction nozzle 5a against an electronic component Good pickup operation can be ensured without causing problems such as component damage.
[0025]
In the above embodiment, since the height detection unit 27 is configured to be detachable, it can be mounted and used only when necessary, and no extra device space is required. Moreover, since it can be shared by a plurality of mounting apparatuses, the apparatus cost can be reduced.
[0026]
【The invention's effect】
According to the present invention, the height position of the height detection point set in correspondence with the electronic component pickup position of the tape feeder is detected by the height position detection means on the dummy jig of the tape feeder mounted on the feeder base. Since the height position of the electronic component is obtained based on the detection result of the height position, it is possible to appropriately control the descending stroke of the transfer head at the time of picking up, such as picking up error or damage to the electronic component. Problems can be prevented.
[Brief description of 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 side view of the electronic component mounting apparatus according to an embodiment of the present invention. FIG. 4 is a block diagram showing a configuration of a control system of the electronic component mounting apparatus. FIG. 4 is an explanatory diagram of tape feeder height detection of the electronic component mounting apparatus according to the embodiment of the present invention.
DESCRIPTION OF SYMBOLS 1 Supply part 2 Tape feeder 2a Pickup position 2 'Dummy jig 2'a Height detection point 5 Transfer head 5a Adsorption nozzle 9 Substrate 23 Feeder height storage part 27 Height detection unit

Claims (1)

An electronic component mounting method for picking up an electronic component held on a tape by a suction nozzle of a transfer head and mounting it on a substrate, on a feeder base on which a tape feeder for supplying the tape to a pickup position by the transfer head is mounted Mounting a dummy jig of the tape feeder on the head, and a height position detecting means for detecting a height position of a height detection point set corresponding to the electronic component pickup position of the tape feeder on the dummy jig Mounting the electronic component mounting apparatus on a fixed part, detecting the height position of the height detection point by the height position detecting means, and storing the height position detection result in the storage unit of the electronic component mounting apparatus A step of storing the electronic component, a step of obtaining a component height position of the electronic component based on the stored height position detection result, and a data of the component height position. And a step of controlling the descending stroke of the transfer head based on the above, and picking up the electronic components held on the tape by vacuum suction with the suction nozzle and mounting them on the substrate positioned in the positioning portion. Electronic component mounting method.

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