JPH01298800A - Electronic component mounting device - Google Patents

Abstract

PURPOSE:To enable mounting in high density without causing position slippage of components resulting from the interference with the neighboring components by rotating a holding means or a slowing the lowering speed of the holding means in case that there is a fear of the holding means or the electronic components interfering with the neighboring components on a circuit board due to position slippage of the holding means. CONSTITUTION:A mounting device detects the runout condition of an absorbing nozzle 20 to electronic components 40 at a station S4 by a TV camera 26 when the electronic components are mounted. At this time, in the rotation of the specific absorbing nozzle 20 to decide the mounting direction of electronic components 41 at a ( theta+theta) rotary station S5, when the nozzle 20 hits on the neighboring components 41 by the runout of the nozzle 20, it is further compensated for rotation by 180 deg. at a station S5. Or, in case that it does not meet this condition, the lowering speed of the nozzle 20 at the time of mounting of components 40 is lowered down so as to weaken shock when the nozzle 20 hits on the neighboring parts 41. Hereby, position slippage of electronic components is prevented, and mounting density and equality in mounting of the electronic components can be improved.

Description

[Detailed description of the invention]

[Field of Industrial Application] The present invention relates to a 5A device in which an electronic component is held by a holding means and the electronic component is mounted at a predetermined position on a circuit board, and particularly relates to a surface mount type electronic component. [Summary of the Invention] Automatic mounting device for surface mount type electronic components When mounting an electronic component, the suction nozzle is moved at a predetermined angle based on the amount of positional deviation of the electronic component suctioned by the suction nozzle, so that the suction nozzle does not hit adjacent and already mounted electronic components. Mounting is performed after the electronic component has been rotated 180 degrees.In addition, the suction nozzle may be attached to parts that cannot be rotated 180 degrees, or even if the above measures are taken, the suction nozzle may In the case of interference, the descending speed of the suction nozzle is slowed down, thereby reducing the impact on adjacent electronic components. In a circuit board in which electronic components are mounted on the circuit board using a surface mount type mounting device such as the one shown in FIG. After that, the electronic component 4 is sucked by a suction nozzle 5, and the electronic component 4 is mounted by lowering the nozzle 5. Part 4 board 1
The adhesion force to the solder cream 3 depends on the adhesive force of the solder cream 3. However, the adhesive strength of this solder cream 3 is very small. Furthermore, as shown in FIGS. 8 and 9, in many cases, the electronic component 4 is suction-held in a state in which the electronic component 4 is offset from the center of the suction nozzle 5.

[Problems to be solved by the invention]

As described above, due to the correlation between the size of the electronic component 4 and the size of the suction surface of the suction nozzle 5, a part of the suction nozzle 5 may protrude from the electronic component 4frX as shown in FIG. In the case where the suction nozzle 5 protrudes from the edge of the electronic component 4, if the electronic component 4 is already mounted at an adjacent position in the protruding direction, the tenth
As shown in the figure and FIG. 11, the suction nozzle 5 may hit the electronic component 4 that has already been mounted. Since the descending speed of the suction nozzle 5 during mounting is constant, when the suction nozzle 5 hits the mounted electronic component 4,
The position of the mounted electronic component 4 will shift due to the impact at that time. In order to prevent such a problem, as shown in FIG. 12, the distance between adjacent electronic components 4 may be increased so that the suction nozzle 5 does not hit the adjacent electronic components 4. However, increasing the distance between adjacent electronic components 4 will reduce the mounting density of the electronic components 4 on the circuit board 1, which will hinder miniaturization of the circuit device. The present invention was made in view of these problems, and even if an electronic component is mounted eccentrically to the suction nozzle, the component may interfere with adjacent components and become misaligned. It is an object of the present invention to provide a mounting device for electronic components that does not cause problems and also enables high-density mounting. Means for Solving Problem 1 The present invention provides an apparatus in which an electronic component is held by a holding means and the electronic component is mounted at a predetermined position on a circuit board, in which the positional deviation of the holding means is fixed. If there is a risk that the holding means or the electronic component may interfere with an adjacent electronic component on the circuit board, the holding means is rotated approximately 180 degrees or the descending speed of the holding means is slowed down. . 1. Therefore, according to the present invention, if there is a possibility that the holding means or the electronic component to be mounted next may interfere with the already mounted electronic component, the holding means is rotated 180 degrees or The lowering speed of the holding means is reduced, thereby preventing interference with adjacent parts,
Alternatively, lff1l will be decreased. Embodiment K] FIG. 2 shows the overall configuration of an electronic component mounting device according to an embodiment of the present invention, in which a plurality of component cassettes 10 are arranged side by side on a moving table 11. It has become. The movable table 11 is supported movably in its length direction by a pair of guide rods 12, and
A feed screw 13 is engaged with this moving table 11. Moreover, the feed screw 13 is driven by a motor 14, so that the movable table 11 is moved in the length direction of the guide rod 12. A rotary table 17 is disposed in front of the movable table 11, and is intermittently rotated about a main shaft 18. Ten component holding units 19 are provided on the rotary table 17 along the circumferential direction. These holding units 19 are provided with suction nozzles 20 for holding electronic components on their lower ends, and have gears 21 on their upper ends. The gear 21 is the gear 23 of the actuator 22 or the gear 25 of the actuator 24.
The suction nozzle 20 is driven by meshing with the suction nozzle 20. Also, a television camera 26 is installed at a predetermined position below the rotary table 17.
is arranged, and the suction nozzle 2 is detected by this camera 26.
It is designed to recognize electronic components that are held at 0. A circuit board 30 on which electronic components are mounted is arranged on an XY table 31. The table 31 is guided by a guide rod 32, and the actuator 33
It is adapted to be moved in the length direction, that is, in the X-axis direction. and a base 34 that supports the guide rod 32.
is guided by a guide rod 35 and moved in the Y-axis direction by an actuator 36. In such a mounting device, a suction nozzle 20 suctions and holds a component from a predetermined cassette 10 at station S1 shown in FIG. The table 17 is rotated intermittently every 36 degrees, and a television camera 26 is used at the station S4 to detect device misalignment of electronic components. Then, at the next station S5, the electronic component is oriented in the mounting direction, and the deviation in the rotational direction is corrected, and the actuator 22 is controlled to rotate by (Δθ+θ). After this, electronic components are mounted 1- at the next station S6. The orientation of the electronic component is achieved by rotating the suction nozzle 20 at the S5 station. On the other hand, as for the deviation in the X-axis direction and the Y-axis direction, the stopping position of the circuit board 30 can be changed by moving the X-Y table 31 on which the circuit board 30 is set using actuators 33 and 36, respectively. I try to do it. After the component is mounted at station $6, the actuator 24 is used to rotate the suction nozzle 20 by -(Δθ100) at the next station S7, thereby bringing the suction nozzle 20 to the origin in the rotation direction. I'm trying to get it back. Furthermore, when mounting an electronic component, this mounting device uses one of the following two methods to move the suction nozzle 20 adjacently depending on the type of the adjacent electronic component that has already been mounted or the electronic component to be mounted. This is to prevent the electronic component from shifting its position due to hitting an already mounted electronic component. As shown in FIG. 1, the mounting direction of the electronic component 40 is 1.
An electronic component 40 that does not have polarity, such as a fixed resistor or a multilayer ceramic capacitor, which does not cause any problem even when rotated by 80 degrees,
If there is enough space on either side of the electronic component 40 to be mounted so that the suction nozzle 20 protruding from the component 40 does not hit the already mounted electronic component 41, the suction nozzle 20 I'm trying to rotate it 180 degrees. That is, as shown in FIG. 5, the state in which the suction nozzle 20 protrudes from the electronic component 40 is detected by the television camera 26 at 84 stations. At this time (Δθ
+θ) When the suction nozzle 20 is rotated in a predetermined manner to determine the mounting direction of the electronic component 41 at the rotation station S5, the suction nozzle 20 protrudes and hits the adjacent electronic component 41 as shown in FIG. 1A. Sometimes, an additional 180 degree rotation correction is performed at the $5 station. This prevents the suction nozzle 20 from hitting the adjacent electronic component 41 as shown in FIG. 1B. That is, depending on the protruding state of the suction nozzle 20, a rotation correction of roughly 0 degrees or 180 degrees is performed for a predetermined rotation at the (Δθ+θ) rotation station S5. In the case shown in Figure 4 where the above conditions are not satisfied,
As shown in FIG. 5, the speed at which the suction nozzle 20 descends when mounting the electronic component 40 is slowed down to weaken the impact when the suction nozzle 20 hits the adjacent electronic component 41. The flowchart shown in FIG. 5 for carrying out such operations is executed in a computer constituting the control unit of the mounting apparatus shown in FIG. The above-described measures are taken on the assumption that the position of the mounted electronic component 41 adjacent to the mounted electronic component 40 or the edge portion of the component 40, 41 is known. However, conventional chip placers do not have such information in the form of final data. Therefore, this mounting device automatically creates such data. The mounting device mounts electronic components 4 for each board 30 to be mounted.
0.41 is mounted, that is, the data of the mount center position in the X-axis direction and the Y-axis direction is input in advance. Then, based on this information, the XY table 31 on which the circuit board 30 is set is moved so that the components 40 and 41 are mounted at predetermined positions. As shown in FIG. 6, if the center of the suction nozzle 20 coincides with the center of the suctioned component, the suction nozzle 20 will be located at the center of the land 42. However, in reality, the suction nozzle 20
In order to hold the part 40 by suction, the position of the suction nozzle 20 is corrected by the amount of this shift before mounting the part 40. This correction is performed in two directions: the X-axis direction and the Y-axis direction. Particularly problematic this time is the correction in the X-axis direction with adjacent parts. Electronic components 40 mounted there
What is necessary is to find the permissible range of the correction value in the X-axis direction to prevent the suction nozzle 20 from hitting the mounted component 41 in each case. Therefore, a method for automatically calculating this allowable range will be described below. When mounting the electronic component 40, if the correction value of the actual position of the suction nozzle 20 in the X-axis direction exceeds the above-mentioned tolerance range, the suction nozzle 20 will hit the adjacent electronic component 41. This operation causes the nozzle 20 to slowly descend. To calculate the allowable range of the correction value in the X-axis direction, as shown in FIG.
6 and capture at 84 stations. Then, the length from the center of the suction nozzle 20 to its outer periphery, that is, the radius, is calculated by pattern recognition. Next, it is detected whether or not electronic components 41 have already been mounted on both sides of the electronic component 40, which is the opposite image of the mount, based on the NC data that defines the position information for mounting the electronic component 40 on the mount 1. In this judgment step, the mounted electronic components 4
1 exists, the distance in the X-axis direction between the center of this electronic component 41 and the center of the position where the electronic component 40 to be mounted is placed is calculated. A mounting device that detects the position of the electronic component 40 using the television camera 26 generally has external shape information of the component 40 as data for pattern recognition. Therefore, the distance from the center position of the electronic component 40 to be mounted to the edge of the adjacent electronic component 41 is calculated using this information and the data regarding the distance between the centers of the components determined by the above calculation. Then, the value obtained by subtracting the data of the radius of the suction nozzle 200 based on the pattern recognition from the data obtained here becomes the allowable range of the correction value of the suction nozzle 20 in the X-axis direction. The mode is selected using data regarding the allowable range of the offset amount. That is, when mounting the electronic component 40, the positional relationship information between this component 40 and the mounted electronic component 41 adjacent thereto is
It is automatically created based on component external shape information, component mounting position information, and pattern recognition information when the component 40 is sucked by the suction nozzle 20. Based on the positional relationship information of the electronic component 40 mounted on the mount 1 and the electronic component 41 mounted adjacent thereto, the suction nozzle 2
One of three modes is automatically specified: a mode in which the suction nozzle 20 is rotated by θ, a mode in which the suction nozzle 20 is further rotated by 180 degrees, and a mode in which the descending speed of the suction nozzle 20 is slowed down. [Effects of the Invention] As described above, the present invention rotates the holding means approximately 181 times when there is a possibility that the holding means or the electronic component may interfere with an adjacent electronic component on the circuit board due to misalignment of the holding means. The descending speed of the holding means is slowed down. As a result, even if the electronic components are mounted at narrow intervals, the electronic components will not be misaligned, thereby improving the accuracy of mounting and improving the quality of mounting the electronic components.

[Brief explanation of the drawing]

Figure 1 is a plan view showing the mounting operation by rotating the suction nozzle by 180 degrees, Figure 2 is a perspective view of the main parts showing the overall structure of the mounting device, and Figure 3 is a plan view showing the structure of the station of the mounting device. Figure 4 is a plan view when the descending speed is slowed down, Figure 5 is a flowchart showing the mounting operation, Figure 6 is a plan view showing the operation of correcting the position of the suction nozzle, and Figure 7 is the allowable offset m. Flowchart showing the operation of calculating the value, FIG. 8 is a front view showing the mounting operation of parts using a conventional suction nozzle, FIG. 9 is a plan view of the same, FIG. FIG. 11 is a plan view showing the operation of interfering with adjacent parts, and FIG. 12 is a plan view when the pitch of the mount is widened. The names of the main parts in the drawings are as follows. 19...Component holding unit 20...Suction nozzle 21...Gear 22...Actuator 23...Gear 26...TV camera 30...Circuit board 40...Electronic component 41... electronic components

Claims (2)

[Claims] 1. In an apparatus in which an electronic component is held by a holding means and the electronic component is mounted at a predetermined position on a circuit board, the holding means or the electronic component may be attached to a circuit due to a positional shift of the holding means. An electronic component mounting device characterized in that the holding means is rotated approximately 180 degrees when there is a risk of interference with an adjacent electronic component on a board. 2. In an apparatus in which an electronic component is held by a holding means and the electronic component is mounted at a predetermined position on a circuit board, the holding means or the electronic component may be mounted on the circuit board due to a positional shift of the holding means. A mounting device for electronic components, characterized in that the lowering speed of the holding means is slowed down when there is a risk of interference with an adjacent component.