JP3077342B2 - Electronic component mounting method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of mounting an electronic component, and more particularly, to a method of mounting two or more multi-tables provided on a movable base in an electronic component supply area. The transfer head picks up the electronic components of the feeder placed on these two tables, and
The present invention relates to a method for quickly switching between these two tables in a method for mounting an electronic component mounted on a substrate on a Y table.

[0002]

2. Description of the Related Art As an electronic component mounting apparatus for mounting electronic components on a substrate, there are an electronic component supply device, an XY table for positioning the substrate, and a rotary head having a transfer head for transferring and mounting the electronic components to the substrate. The configured ones are widely implemented. The electronic component supply device includes a table on which a plurality of feeders such as a tape feeder and a tube feeder equipped with electronic components are placed, and a moving table that moves the table in a horizontal direction.

In such an electronic component mounting apparatus, while a transfer head rotates in an index, an electronic component of a desired feeder is picked up and mounted at a predetermined coordinate position on a substrate positioned on an XY table. I have.

[0004] A multi-table type electronic component supply apparatus in which a movable table is provided with a large number of tables has been proposed (Japanese Patent Application Laid-Open No. 1-300598). Such a multi-table type electronic component supply apparatus moves each table independently in the horizontal direction, and divides the table into a plurality of tables to reduce the weight of each table. There is an advantage that the moving speed can be increased and the mounting speed of the electronic component on the substrate can be increased.

[0005]

As a mounting form of electronic components in the multi-table type electronic component supply apparatus as described above, two tables out of a large number of tables are located in a supply area at a central portion of a movable base. When the electronic components on the two tables are mounted on a board on the XY table, that is, when, for example, 100 electronic components are mounted on one board, the first 50 components are supplied from one table. It is known that the remaining 50 are supplied from the other table to complete the mounting of the electronic component on one board. In this case, the electronic components are supplied to the transfer head while moving one of the tables in the horizontal direction, and when the supply of the electronic components from this table is completed, the table is retracted to the side and replaced with this table. Thus, the other table supplies the electronic components to the transfer head.

[0006] However, such table switching requires a considerable switching time (normally 1 to 1.2 seconds), and this switching time results in a loss time, which lowers the mounting efficiency.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an electronic component mounting method capable of minimizing a loss time at the time of switching tables and avoiding a reduction in electronic component mounting efficiency.

[0008]

According to the present invention, a histogram of the number of electronic components to be picked up from each feeder on a table is created, and the electronic head picked up from one table by a transfer head is prepared. If the recognition unit recognizes the component and it is confirmed that the electronic component is normally picked up, the number of the corresponding electronic components in the histogram is subtracted, and this subtraction is repeated, and the number of the electronic components in the histogram in one table is reduced. If the remaining number decreases, the other table is brought closer to the electronic component supply end scheduled position of the one table, and if the electronic components of the histogram of the one table are exhausted, the one table and the other table are used. Table is switched.

[0009]

According to the above arrangement, when the number of remaining electronic component histograms in one of the tables for supplying electronic components to the transfer head in the supply area decreases, the other table is added to this one table. Get closer. When the electronic components in the histogram of one of the tables become zero and retreat to the side, the other table immediately moves to the pickup position, and the supply of the electronic components to the transfer head can be continued. Loss time associated with switching can be greatly reduced.

[0010]

Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a perspective view of the electronic component mounting apparatus. 1
Is a main body box in which a rotary head 2 is provided. The rotary head 2 has a large number of transfer heads 3. An XY table 4 is provided below the rotary head 2. The XY table 4 moves the substrate 5 in the XY directions. Reference numeral 10 denotes an electronic component supply device, and its detailed structure will be described below.

Reference numeral 11 denotes a moving table, on which a large number of tables 12 are mounted. In this embodiment, the number of tables 12 is eight. By dividing the table 12 into a number of multi-tables in this manner, the weight of one table 12 is reduced, and even if the table 12 is moved at high speed on the moving base 11 and suddenly stopped, a large vibration is caused by the shock. , The stop position accuracy is improved, and movement can be started with good rise.

As shown in FIGS. 2 and 3, the movable base 11 is provided with a rail 13 in the X direction. Table 12
Is provided with a slider 14 that engages with the rail 13, and the table 12 moves laterally along the rail 13.

A feeder 15 for electronic components P is placed on the table 12. The feeder 15 is a tape feeder, and is configured by mounting a tape supply reel 17 on a frame 16, and supplies an electronic component P stored in a tape 18 to the transfer head 3.

The transfer head 3 has a nozzle 6, and at the pickup position K, the electronic component P of the feeder 15
To pick up. As the feeder, a tube feeder or the like is often used in addition to the tape feeder described above.

In FIG. 3, the center of the movable base 11 is a supply area A, and both sides are retreat areas B1 and B2. In the supply area A, two ball screws 21 and 22 are provided. Nuts 2 for ball screws 21 and 22
3, 24 are mounted (see FIG. 2), and nuts 23,
On the cylinder 24, cylinders 25 and 26 are provided. When the motors 27 and 28 are driven, the nuts 23 and 24 move along the ball screws 21 and 22. In FIG. 2, 3
Reference numerals 1 and 32 denote sliders and rails for guiding the sliding of the nuts 23 and 24, and 33 denotes a base. Holes 35 and 36 are formed in the lower part of the table 12. Cylinder 25, 2
The sixth rods 25a, 26a engage with the holes 35, 36.

When the ball screws 21 and 22 rotate in a state where the rods 25a and 26a are engaged with the holes 35 and 36, the table 12 is pulled by the rods 25a and 26a and is moved in the lateral direction (X direction). Go to That is, each of the components 21 to 26 serves as a first feeding unit of the table 12. Ball screws 21, 22 and nut 23,
Reference numeral 24 has an accurate feeding precision, and can stop the predetermined feeder 15 at the pickup position K of the transfer head 3 correctly.

In FIG. 1, a timing belt 41 is provided on the side of the movable base 11. 42 is a timing pulley and 43 is a drive motor. A long bracket 44 is attached to the timing belt 41.

A cylinder 45 is mounted on the bracket 44 (see also FIG. 2). Also this bracket 4
4, holes 46 for projecting the rod 45a of the cylinder 45 are formed at a pitch. In FIG. 2, a hole 47 is formed in the lower surface of the table 12. When the timing belt 41 rotates while the rod 45a of the cylinder 45 is engaged with the hole 47, the table 12 is pulled by the rod 45a and moves in the lateral direction (X direction). In FIG. 2, reference numerals 37 and 38 denote rails and sliders for guiding the movement of the bracket 44.

That is, the components 41 to 45 constitute the second feeding means of the table 12. This second
Feeding means 41 to 45 move the table 12 to the retreat area B
1, between B2 and the supply area A,
Therefore, the bracket 44 moves between the evacuation areas B1 on both sides and the evacuation area B2. Unlike the first feeding means 21 to 26, the second feeding means 41 to 45 do not require accurate feeding accuracy, and are therefore constituted by inexpensive components such as the timing belt 41.
49 is an electric cable.

2 and 3, the evacuation area B1,
A cylinder 48 is provided on the side of B2. When the rod 48a of the cylinder 48 presses against the side surface of the table 12, the retracted table 12
Fix so that it does not move unnecessarily due to the vibration of 1. That is, the cylinder 48 is a fixing means of the table 12 in the evacuation areas B1 and B2.

In FIG. 3, reference numeral Q1 denotes a first recognition unit, which detects whether or not the electronic component P is normally sucked at the lower end of the nozzle 6 by optical means such as an optical sensor. This recognition section Q1 is similar to the means described in Japanese Patent Application Laid-Open No. 61-142411. Q2 is a second recognition unit. FIG. 4 shows the recognition unit Q2, in which the camera 9 observes the electronic component P sucked by the nozzle 6, and recognizes the positional shift.

FIGS. 5A to 8B show two tables 12 (hereinafter referred to as tables A and 12) located in the supply area A.
Table B) and the change over time of the histogram of the electronic components of Table A. The electronic components P of the feeder 15 on the two tables A and B are mounted on the substrate 5 on the XY table 4. In this embodiment, ten feeders 15 (No. 1 to No. 10) are placed on the table A. This histogram is created based on a mounting program, and indicates the number of electronic components P to be picked up from each of the feeders 15 (No1 to No10) on the table A. If the first recognition unit Q1 or the second recognition unit Q2 recognizes that the electronic component P is normally picked up, the corresponding electronic component P in the histogram is subtracted by one.

FIG. 5A shows an initial state. At this time, the two tables A and B are approaching at a small interval t. The small interval t is a safety interval secured to avoid collision between the two tables A and B. Now, one table A is moved from the position shown in FIG. 5A to the supply start position shown in FIG. In this embodiment, first, the electronic component P of the No. 4 feeder 15 is supplied to the transfer head 3. Next, while reciprocating the table A in the horizontal direction (X direction), the feeders 15 having the desired electronic components P are sequentially stopped at the pickup position K, and the electronic components P are sequentially supplied to the transfer head 3.

The transfer head picking up the electronic component P to the nozzle 6 transfers the electronic component P to the substrate 5 on the XY table 4 while rotating the index. Then, it is checked whether or not the electronic component P is normally sucked to the nozzle 6, and if it is normally sucked, the number of histograms of the corresponding electronic component P is subtracted by one. Next, the electronic component P is observed by the second recognition unit Q2, and the displacement in the XYθ direction is recognized. Of the positional deviations in the XYθ directions, XY
The position shift in the direction is corrected by adjusting the movement stroke of the substrate 5 in the X and Y directions, and the position shift in the θ direction is corrected by rotating the nozzle 6 by θ. Mount. In this way, every time the recognition unit Q1 recognizes that the electronic component P has been normally picked up, the number of corresponding electronic components P in the histogram is repeatedly reduced by one.

FIG. 7A shows a state where the electronic component P of the feeder 15 of No. 10 is being picked up.
As shown in FIG. 7B, in this state, the electronic components P of the feeders 15 of No. 1 to No. 8 become zero due to the repetition of the subtraction. In this state, the electronic component P of the feeder 15 of No. 10 soon becomes zero, the electronic component P of the feeder 9 of No. 9 also becomes zero, and all the histograms of the electronic component P of one table A become zero. It turns out that the timing, that is, the time to switch the table A to the table B will come soon. In the table A, when the feeder 15 of No. 9, which supplies the electronic component P to the transfer head 3 last, is located at the pickup position K, the electronic component supply end position of the table A (all histograms of the electronic component P are zero) End position S1 can be easily determined from known data such as the dimensions of the table A. Then, the other table B, which has been waiting on the side until then, is moved to the right approach position S.
Slide 2 to prepare for switching between table A and table B. The interval between the two positions S1 and S2 at this time is the small distance t.

Subsequently, the last No. 9 feeder 15 of the table A is stopped at the pickup position K (FIG. 8).
(A)) When the electronic components P of the feeder 15 are picked up by the transfer head 3 and all the electronic components P in the histogram of the table A become zero, the table A is retracted to the side evacuation area B2. Then, the other table B moves to the pickup position K, and the supply of the electronic component P to the transfer head 3 is continued. As described above, the present method causes the other table B to approach the table A when the supply of the electronic component P from the one table A is near the end and the switching time between the table A and the table B is near. Therefore, the switching from the table A to the table B can be performed in a very short time (for example, about 0.3 seconds), and the loss time for the switching can be significantly reduced. Of course, the approach operation of the table B may be started earlier.

The reason why the number of histograms is subtracted after the recognition section Q1 recognizes that the electronic component P has been normally sucked is as follows. That is, the electronic component P of the feeder 15 is not always sucked normally by the nozzle 6, but may be sucked in a standing posture, for example. In such a case, the mounting of the electronic component P on the substrate 5 is stopped, and the nozzle 6 of another transfer head 3 picks up the electronic component P from the feeder 15 again and mounts the electronic component P on the substrate 5. Such an operation is generally called recovery.
Therefore, in the present method, the recognition unit Q1 recognizes that the electronic component P has been normally sucked, and confirms that the electronic component P is mounted on the board 5 as scheduled before subtracting the histogram. ing. Of course, the subtraction may be performed after the electronic component P is recognized by the second recognition unit Q2, and the recognition unit may perform the recognition arbitrarily. Therefore, it is desirable that the recognition be performed by the first recognition unit Q1, which is the upstream recognition unit.

FIG. 9 is a flowchart of the above operation. In step 1, histograms of all tables 12 are created. In step 2, the electronic component P is recognized by the recognition unit Q1 or Q2. In step 3, whether or not the pickup of the current table (table A in the present embodiment) is completed is selected. Next, if the recognition is normal, the histogram is subtracted (steps 4 and 5), and access to the table (table B in this embodiment) is selected. If NO, the process returns to Step 2, and the above operation is repeated. If YES, Table B approaches Table A (Step 7). This approach interval is the small interval t as described above. If an abnormality is detected in step 4, the above-described recovery is performed and error processing is performed. If YES in step 3, it is determined in step 8 whether or not all tables have been completed.
If O, switch the table and return to step 2
If S, the program is END.

[0029]

As described above, according to the present invention, when the number of remaining electronic component histograms in one table for supplying electronic components to the transfer head in the supply area decreases, the number of electronic component components decreases. When the histogram becomes zero, that is, when the table is switched, and the electronic component supply end position of this table at that time is known, the other waiting table is brought closer to this one table, and When the electronic component histogram becomes zero and retreats, the other table immediately moves to the pick-up position and the supply of electronic components to the transfer head can be continued, greatly reducing the loss time when switching tables. In addition, the mounting efficiency of electronic components can be improved.

[Brief description of the drawings]

FIG. 1 is a perspective view of an electronic component mounting apparatus according to the present invention.

FIG. 2 is a partial side view of the same.

FIG. 3 is a plan view of the same.

FIG. 4 is a partial side view of the same.

5A is a plan view of the same table, and FIG.

6A is a plan view of the table, and FIG.

7A is a plan view of the table, and FIG.

8A is a plan view of the table, and FIG.

FIG. 9 is the same flowchart.

[Explanation of symbols]

 Reference Signs List 3 Transfer head 4 XY table 5 Substrate 6 Nozzle 11 Moving table 12 Table 15 Feeder A Supply area P Electronic component Q1 Recognition unit Q2 Recognition unit S1 Scheduled end of electronic component supply

Continuation of front page (56) References JP-A-2-130897 (JP, A) JP-A-3-257900 (JP, A) JP-A-4-369294 (JP, A) JP-A-5-275886 (JP) JP-A-62-140499 (JP, A) JP-A-63-60599 (JP, A) JP-A-3-93297 (JP, A) JP-A-3-238897 (JP, A) (58) Field surveyed (Int. Cl. ⁷ , DB name) H05K 13/00 H05K 13/02

Claims (1)

(57) [Claims] 1. A multi-table is provided on a movable base, and two of the multi-tables are positioned in a supply area at the center of the movable base. Is picked up by a transfer head, and the transfer head rotates by an index, so that the electronic components of the feeders on the two tables are moved in XY.
In the electronic component mounting method, the electronic component picked up from the one table to the transfer head is recognized by a recognition unit provided in the middle of a path of the transfer head. Then, if it is confirmed that the pick-up is normally performed, the number of the corresponding electronic components in the histogram of the number of the electronic components to be picked up from each feeder on each of the tables is subtracted, and this subtraction is performed. If the number of remaining electronic components in the histogram of the above one table decreases repeatedly,
Bringing the other table closer to the electronic component supply end scheduled position of the one table, and then switching between the one table and the other table when the electronic components of the histogram of the one table are exhausted. An electronic component mounting method characterized by the above-mentioned.