JPH0128519B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides an IC or a
This relates to a device that automatically positions and automatically joins the leads of mounted components such as LSI.

[Conventional technology]

Conventionally, when attaching flat pack components such as ICs and LSIs to a printed board, the printed board is placed in advance at a specified position on a table that can be moved in the X and Y directions, and a large number of parts printed on the printed board are After accurately positioning the leads of the component on the bonding pad, a fixing method is used in which solder that has been previously adhered and solidified is reheated and bonded (hereinafter referred to as reflow soldering). This positioning work is performed by using an optical microscope or by enlarging and projecting the lead portion of the component onto a screen and manually performing minute positional movements.

[Problem to be solved by the invention]

However, the conventional alignment method described above has a problem in that it takes time to obtain high alignment accuracy. Note that automatic alignment methods have also been devised, but these generally involve detecting a part of the component, such as a corner of the component, with an optical detector and aligning the parts.

However, such a method has a problem in that, for example, if the lead of one terminal at the end of a component selected as an alignment reference is bent, the alignment of the component may become incorrect.

The purpose of the present invention was to solve the above-mentioned problems, and to provide a new automatic component positioning and joining device equipped with a precision movement mechanism using optical detection in the X, Y directions and rotation angle direction. be.

[Means to solve the problem]

In order to achieve the above-mentioned object, the present invention is an apparatus for precisely positioning and joining flat pack-shaped parts on the joining pad of a printed circuit board placed on a rough moving table, and the invention is an apparatus for suctioning and joining the parts to be positioned at the lower end. A main shaft having a spline shaft integrally formed at its upper end is vertically supported by a spherical bearing containing a linear bearing, and a spline bearing is provided at the upper end of the main shaft through which the spline shaft is inserted. A rotation adjustment mechanism and an X, Y precision movement mechanism are connected to the spline bearing via a swing joint, and the alignment relationship between the component held by the suction means and the joining pad on the printed board is detected. The apparatus further includes an optical control means for controlling the operation of the precision movement mechanism.

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of an automatic positioning and joining device for parts according to the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a schematic configuration diagram for explaining one embodiment of the present invention.

In the figure, reference numeral 1 denotes an X, Y moving table capable of moving a printed board 2 on which a plurality of bonding pads 21 are formed, in the X and Y directions, and 3 a plurality of leads 31 mounted on the printed board 2. It is a component consisting of a flat pack type IC etc. equipped with
On the component 3, a component chuck 62 for suctioning and holding the component 3 is disposed at the lower end connected to the vacuum pump 7, and a main shaft 6 (not shown) is integrally formed with a spline shaft 63 at the upper end. A linear bearing 40 with a built-in ball 40a provided on the B support substrate 5 supported by a vertical movement support means allows for vertical movement, and a spherical bearing 11 containing the linear bearing 40 allows for rotation and movement forward, backward, left and right. It is supported vertically so that it can swing.

The spline shaft 63 is a precision movement mechanism arranged on a support (not shown), that is, an X, Y, θ mechanism fixed on an XY movement table 13a arranged on the support.
The table 13 is inserted into and supported by a spline bearing 137 disposed through a swing joint 136 equipped with a gear 135 so as to be movable in the vertical direction.
By driving a rotation angle motor 133 disposed on the table 13, the table 13 can be minutely rotated in forward and reverse directions via a motor-side gear 134 combined with the gear 135.

The specific structure of the spline bearing 137 and the swing joint 136 through which the spline shaft 63 is inserted and supported is as shown in the partially enlarged perspective view of FIG.
The gear 13 is inserted into a through hole provided at a predetermined position of the X, Y, θ table 13 through a bearing 139.
An outer ring 136a on which a number 5 is fitted is rotatably disposed, and an inner ring 136b is supported within the outer ring 136a so as to be swingable in the X direction by a pair of pivots 138b. 137 is also supported swingably in the Y direction by a pair of pivots 138a.

Therefore, as shown in FIG. 1, the X, Y, θ table 13 is moved by the X-axis motor 13 of the
1 and the Y-axis motor 132, the swinging motion in the X and Y directions of the main shaft 6, which is integrated with the spline shaft 63 inserted through the spline bearing 137, causes the ball to move in the X and Y directions. This is achieved smoothly using the bearing 11 as a fulcrum, and the movement of the main shaft 6 in the rotation angle direction, that is, the θ direction, is achieved by driving the rotation angle motor 133 from the motor side gear 134 to the swing joint side gear 135 to the swing joint 136. → Spline bearing 137 → Smooth transmission via spline shaft 63.

Further, reference numeral 4 denotes an A support board which is supported by a vertical movement support means (not shown) and which lifts and lowers the B support board 5 via a stopper 41 by driving the A cylinder 14a and the B cylinder 14b.
A reflow chip 12 is held so as to correspond to the upper bonding pad 21. 8 is a support rod attached to the B support board 5; 9 is a lead 31 of the component 3 to the bonding pad 21 of the printed board 2;
A sensor camera 10 detects the positional relationship between the X, Y and θ tables 13 in a predetermined direction based on the position signal output; It is a C cylinder that moves up and down to engage the main shaft lever 101 with the groove of the main shaft 6, thereby slightly raising and lowering the supported main shaft 6.

Next, the operation of the above device configuration will be explained using FIG. 1.

First, a printed board 2 on which a plurality of bonding pads 21 are formed is placed at a prescribed position on the X, Y moving table 1, and the mounting position of the component 3 consisting of an IC or the like on the printed board 2 is determined by the printed circuit board 2. A component chuck 62 at the lower end of the main shaft 6 facing away from the plate 2
After the A cylinder 14a is turned on (the B cylinder 14b is turned off), the A support substrate 4 to which the A cylinder 14a is connected is raised to the uppermost position in the direction of the arrow.

At this time, the B support board 5 is also pushed up by contact with the stopper 41 provided on the A support board 4 which is rising, and rises together with the main shaft lever 1 attached to the B support board 5 and driven by the C cylinder 10.
The main shaft 6, which is engaged and supported by 01, also rises in the direction of arrow F.

Next, the component 3 is temporarily placed on the printed board 2 corresponding to the component chuck 62 by another component transfer means (not shown), and the C cylinder 10 is moved.
OFF, operate the main shaft lever 101, lower the main shaft 6 in the direction of arrow G, bring the component chuck 62 at the lower end of the main shaft 6 into contact with the component 3, and at the same time open a vacuum suction hole in the component chuck 62. 61
The vacuum pump 7 connected to the vacuum pump 7 is driven to hold the component 3 on the component chuck 62 by suction.

Next, turn on the C cylinder 10 and turn on the main shaft lever 1.
01 is operated to raise the main shaft 6 with the component 3 sucked up to the highest position in the direction of arrow F. Here, the A cylinder 14a is turned off again, and the B support substrate 5 supported by the A support substrate 4 is lowered together via the A support substrate 4 and the stopper 41, and the B support substrate 5 is The support rod 8 is stopped at the position where the tip of the support rod 8 attached to the board contacts the printed board 2. At this time, the A support substrate 4 is stopped at a position slightly lower than that.

In this way, the lead 31 of the component held by the component chuck 62 faces the bonding pad 21 of the printed board 2 with a predetermined small gap maintained. Here, the sensor camera 9 is operated to image the positional relationship between the leads 31 of the component 3 and the bonding pads 21 of the printed board 2 facing each other, and the positioning is controlled based on the imaged signal. Not alignment control circuit,
That is, the optical detection device shown in FIG. 2, which will be described later, detects the
Drive the axis motor 131 and the Y-axis motor 132,
The X, Y, θ table 13 is moved in the X, Y directions, the main shaft 6 is oscillated in the X, Y directions via the swing joint 136, and the spherical bearing 11 is used as a fulcrum, and the rotation angle motor 133 is moved. By driving, the main shaft 6 is slightly rotated in the forward and reverse directions to accurately position the lead 31 of the component 3 at the lower end of the main shaft 6 on the bonding pad 21 of the opposing printed board 2.

After completing this alignment, the A cylinder 14a is
By turning on the A support board 4 and raising it to the highest level, the B support board 5 and the main shaft 6 are also raised, and the component 3 is separated from the top of the printed board 2, and the surface of the bonding pad 21 of the printed board 2 is After applying flux by a means not shown, A
At the same time, the cylinder 14a is turned off, and the C cylinder 10 is also turned off, and the A support board 4, B support board 5, and main shaft 6 are lowered, and the leads 31 of the component 3 are lowered.
is in close contact with the bonding pad 21 of the printed board 2, turn on the B cylinder 14b, lower the A support board 4, and bring the reflow chip 12 provided on the A support board 4 into contact with the lead 31 and press it. do. Then, a current is applied to the reflow chip 12 to connect the bonding pad 21 and the leads 3 of the component 3.
The solder attached to 1 in advance is heated and melted to join them together.

After this bonding, turn off the current to the reflow step 12.
After turning OFF and releasing the suction of the component 3 by the component chuck 62 after a predetermined cooling time, the B cylinder 14b is turned OFF and the reflow chip 12 is raised together with the A support board 4, and the B support board 5 and the main shaft are also lifted. By raising the printed board 2
The joining of the component 3 to the joining pad 21 is completed.

Note that there is a risk that the vapor of the flux applied to the printed board 2 during soldering may adhere to the lens of the sensor camera 9.
This is prevented by installing an air jet nozzle (not shown) near the lens to prevent flux vapor from flowing into the lens.

FIG. 2 is a schematic diagram for explaining the outline of an optical detection device that controls the alignment of the leads 31 of the component 3 to the bonding pads 21 of the opposing printed board 2, and shows the same part as in FIG. 1. The same reference numerals are added to .

In the figure, 3 is the bonding pad 2 of the printed board 2.
For example, it is a part consisting of an IC package with a large number of leads 31 to be aligned on the side, and a sensor camera is placed above these. 9 is placed.

Then, the sensor camera 9 detects the component 3.
The imaged video signal V is waveform-shaped by a waveform shaping circuit 15, and is sent to a microprocessor (MPU) as digital signal data D. )17. In addition, a clock signal CLK, a start signal ST, etc. are also output. 16 is an input/output interface section therebetween.

In the microprocessor 17, the data D
A forward signal F or a backward signal B is applied to the drive control circuit 18 based on the result of the calculation process, and the control signal from the circuit 18 controls the XY moving table 13a in the precision movement mechanism. X-axis motor 131 and Y-axis motor 1
32 and a rotation angle motor 133 on the X, Y, θ table 13, the main shaft 6 is moved by moving the X, Y, θ table 13 in the X and Y directions. The component 3, which is suctioned and held by the component chuck 62 at the lower end of the main shaft, is moved in the directions of arrows X, Y, and θ through the swing joint 136 and with the spherical bearing 11 as a fulcrum. Positioning is performed until the leads 31 of the printed circuit board 2 are accurately aligned with the bonding pads 21 of the printed board 2. A keyboard 20 is used to input various program information to control the microprocessor 17, and is also connected to the microprocessor 17 via an input/output interface section 22.

In addition, in this embodiment, an example has been described in which a cylinder-based driving means is used as a driving source for raising and lowering the A support substrate 4 and the B support substrate 5, but the present invention is limited to such a cylinder-based driving means. Alternatively, a driving means using a motor may be used instead. Furthermore, the flux applied to the surface of the printed circuit board 2 may be pre-flux. Furthermore, although vacuum suction is used to chuck the parts, it is also possible to chuck the parts mechanically.

〔Effect of the invention〕

As is clear from the above description, according to the automatic component positioning and joining device according to the present invention, the leads of a component such as a flat pack IC can be automatically positioned with respect to the joining pad of a printed circuit board without manual work. It is now possible to perform this process with high accuracy, significantly improving the quality of printed circuit boards on which components such as flat pack ICs are mounted, and improving the efficiency of the alignment process and soldering process. The effect is great.

[Brief explanation of drawings]

FIG. 1 is a schematic configuration diagram for explaining an embodiment of an automatic positioning and joining device for parts according to the present invention;
FIG. 2 is a schematic diagram for explaining the outline of the optical detection device according to the present invention, and FIG. 3 is a schematic diagram for explaining the outline of the optical detection device according to the present invention.
FIG. 2 is a partially enlarged perspective view showing a specific example structure of a spline shaft, a swing joint, and a main shaft and a spherical bearing integrated with the spline shaft in the figure. In Figures 1 to 3, 1 is an X, Y moving table, 2 is a printed circuit board, 3 is a component, 4 is an A support board, 5 is a B support board, 6 is a main shaft, 7 is a vacuum pump, and 8 is a support 9 is a sensor camera, 10 is a C cylinder, 11 is a spherical bearing, 12 is a reflow chip, 13 is an X, Y, θ table, 13a is an X, Y
A moving table, 14a is an A cylinder, 14b is a B cylinder, 15 is a waveform shaping circuit, 16 and 22 are input/output interface sections, 17 is a microprocessor,
18 is a drive control circuit, 19 is a motor, 20 is a keyboard, 21 is a joining pad, 31 is a lead, 40
41 is a linear bearing, 41 is a stopper, 61 is a vacuum suction hole, 62 is a component chuck, 101 is a main shaft support lever, 136 is a swing joint, and 137 is a spline bearing.

Claims (1)

[Scope of Claims] 1. A device for precisely positioning and joining a flat pack type component 3 on a joining pad 21 of a printed circuit board 2 placed on a coarse moving table 1, which sucks the component 3 to be positioned at the lower end. A spline shaft 63 is provided at the upper end.
A main shaft 6 integrally formed with the main shaft 6 is vertically supported by a spherical bearing 11 containing a linear bearing 40, and a spline bearing 137 is provided through which the spline shaft 63 at the upper end of the main shaft 6 is inserted. The rotation adjustment mechanism and the X, Y precision movement mechanism are connected via the swing joint 136, and the alignment relationship between the component 3 held by suction by the suction means 62 and the bonding pad 21 on the printed board 2 is detected. and an optical control means for controlling the operation of the precision movement mechanism.