JPH04798A - Electronic component mounting apparatus - Google Patents

Abstract

PURPOSE:To eliminate a takeup mistake, a placing mistake by measuring the thickness of an electronic component sucked to a nozzle by a measuring unit, calculating the average value of the thicknesses of the components by a computer, and regulating an elevation stroke of the nozzle based on the average value. CONSTITUTION:A transfer head 7 which sucks an electronic component C in a supply unit 12 is conveyed to a placing unit 3 by the indexing of a rotary head 2. A measuring unit 80 is arranged on the way of a conveying path to measure the thickness of the component C sucked to the lower end of a nozzle 8, the measurement signal is input to a computer 59, which calculates the average value of the thicknesses D1-Dn of the components C1-Cn registered in the computer 59 in advance and the measured values to correct the thickness, and then a pulse motor 50 for driving a regulator 58 is controlled based on the correction value thereafter, thereby regulating the elevation stroke of the head 7.

Description

Detailed Description of the Invention (Industrial Field of Application) The present invention relates to an electronic component mounting apparatus, in which the thickness of an electronic component attracted to a nozzle is measured by a measuring device, an average value thereof is obtained, and this average value is Based on this, by adjusting the vertical stroke of the nozzle, it is possible to eliminate tick-up errors and mounting errors of electronic components.

(Prior art) An electronic component mounting apparatus is designed to tick up electronic components by raising and lowering a nozzle of a transfer head in an electronic component supply section, and then transfer and mount the picked up electronic components onto a board in a mounting section. It has become.

(Problem to be solved by the invention) However, since electronic component mounting equipment is operated at high speed, there is a problem in which the nozzle easily makes many mistakes in ticking up electronic components.One of the causes of this is that the nozzle Because of the variation in the height of the lower end, the present applicant has previously proposed a solution to this problem (Japanese Patent Laid-Open No. 1-261899). However, tick-up errors are caused not only by the above causes but also by variations in the thickness of electronic components. In other words, even if the electronic component is the same, there will be variations in thickness due to molding errors, and if the thickness is too small, the bottom end of the nozzle will not be able to land on the top surface of the electronic component, resulting in a tick-up error and the thickness will be too large. Then, the lower end of the nozzle lands strongly on the top surface of the electronic component, destroying the electronic component.

Furthermore, for the same reason, a mounting error occurs in the mounting section. In other words, if the thickness of the electronic component is too small, the electronic component will not be able to land on the board even if the nozzle descends, and the nozzle will release the suction state before landing, causing the electronic component to fall naturally. This may cause misalignment or vertical alignment. Furthermore, if the thickness of the electronic component is too large, the electronic component that lands on the board will be pressed by the nozzle and destroyed.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a means for eliminating tick-up errors and mounting errors caused by variations in the thickness of electronic components.

(Means for Solving the Problems) For this purpose, the present invention includes an electronic component supply section and a mounting section for mounting the electronic component on a board, and in the supply section,
In an electronic component mounting apparatus in which a nozzle of a transfer head is raised and lowered to attract electronic components to the lower end of the nozzle and transferred and mounted on the board, a measuring device is installed between the supply section and the mounting section. The measuring device measures the thickness of the electronic components attracted to the nozzle, calculates the average value of the thickness of the electronic components using a computer, and then adjusts the vertical stroke of the nozzle based on this average value. It is designed to adjust.

(Function) In the above configuration, when the electronic component is picked up in the supply section and transferred to the transfer nozzle, the measuring device detects the electronic components adsorbed to the lower end of the nozzle. Measure the thickness of the part. This measurement is performed for each type of electronic component, and the average value of the thickness of each electronic component is calculated. Based on this average value, the nozzle's vertical stroke is adjusted to eliminate tick-up errors and mounting errors.

(Example) Hereinafter, the present invention will be described in detail with reference to the drawings, taking a rotary head type electronic component mounting apparatus as an example.

FIG. 1 is a perspective view of an electronic component mounting apparatus, in which 1 is a main box, 2 is a rotary head rotatably attached to the lower part of this box I, 3 is an XY child table, and 5 is a mounting device for electronic components. Department. 6 is a board positioned on the mounting part 3 by the clamp part IO, and the board 6 is
The child table 5 slides in any direction J and is positioned. On the lower surface of the rotary head 2, a large number of transfer hend doors are arranged in parallel along the circumferential direction, and each transfer head 7 is equipped with a nozzle 8 that protrudes downward (see also Figure 2). reference). A spring 9 is provided to allow the nozzle 8 to move slightly up and down.

This nozzle 8 is connected to the electronic component C at its lower end by vacuum pressure.
adsorbs.

FIG. 3 is a plan view of the rotary head 2, and 12 is a supply section for electronic components C disposed on the opposite side of the mounting section 3, and as described later, index rotation of the rotary head 2 in the N direction is performed. Then, by the vertical movement of the nozzle 8, the electronic component C in the supply section 12 is picked up and transferred and mounted on the board 6.

In FIG. 3, reference numeral 13 denotes a recognition device disposed between the supply section 12 and the mounting section 30, which detects errors in the XY force direction and rotation direction of the electronic component C attracted to the lower end of the nozzle 8. . The XY force direction error is corrected by moving the substrate 6 in the same direction. Furthermore, the error in the rotational direction is detected by driving the motor 14 (see FIG. 2) mounted on the rotary head 2, which drives the belt 15, spline shaft 16, gear 17, etc.
18 etc., the transfer head 7 is rotated in the H direction (see FIG. 3) about its axial center line for correction. Reference numeral 80 denotes a measuring device disposed on the transfer path from the supply section 12 to the mounting section 3, which measures the thickness of the electronic component C adsorbed by the nozzle 8. The detailed structure will be explained with reference to FIG.

81 is the mounting bracket, 82 is this bracket 81
83 is a cam driven by the pulse motor 82, 84 is a cam follower that comes into contact with the circumferential surface of the cam 83, and 85 is an elevating plate connected to the cam follower 84 via a connecting member 86. . The elevating plate 85 is connected to the bracket 81 via spring members 87, 87 that urge it downward, and when the cam 83 is rotated by the drive of the motor 82, the elevating plate 85s moves up and down in the vertical direction P. 88 is a guide rail attached to the front surface of the bracket 81, 89 is a slider attached to the back surface of the elevating plate 85, and the slider 89 moves up and down along the guide rail 88. Reference numeral 90 denotes a support plate attached to the lower end of the elevating plate 85, which protrudes horizontally to the front, and measurement elements 91 and 92 are disposed at its tip across the conveyance path of the nozzle 8.

When the pulse motor 82 is driven to rotate the cam 83,
The support plate 90, which follows the circumferential surface of the cam 83 via the cam follower 84, descends from above to below (see the solid line and chain line in FIG. 6), and measures the thickness of the electronic component C attracted to the lower end of the nozzle 8. , the measurement results are input to a computer 59 (described later). The rotational speed of the cam 83 is synchronized with the index rotation pitch of the rotary head 2, and the above measurement is performed by driving the pulse motor 82 while the rotary head 2 is intermittently stopped.

Next, the drive mechanism of the transfer head 7 will be explained with reference to FIGS. 1 and 2.

20 is a drive unit box disposed directly above the rotary head 2 in the box 1, and 2 is a drive unit box 20.
22 is a support frame. The rotary head 2 is attached to the output shaft 23a of the drive unit box 20, and the rotary head 2 is driven by the drive unit 21.
rotates the index. The drive unit 21 is a servo motor, and its power is transmitted to the transfer head 7 via a transmission path described below, and the transfer head 7 is moved up and down with a predetermined stroke.

25a is another output shaft 23b of the drive unit box 20
The pulley attached to 25b is another pulley,
Reference numeral 26 is a timing belt which is wound around eight times around the pulleys 25a and 25b, and 27 is a rotation axis of the pulley 25b. Cams 30 and 30 are attached to both ends of the rotating shaft 27 in order to raise and lower the transfer head 7 at two locations, the supply section 12 and the mounting section 3. Since the elevating mechanism for the transfer head 7 in the supply section 12 and the mounting section 3 is the same, the elevating and lowering mechanism on the mounting section 3 side will be described below with particular reference to FIG. 2.

31 is a cam follower that comes into contact with the circumferential surface of the cam 30;
It is pivoted to a key-shaped lever 33. A coil spring 34 presses the cam follower 31 against the cam 30. The cam follower 31 moves up and down following the rotation of the cam 30, and the lever 33 swings about the pin 32 in the direction of arrow a. That is, these members 30 to 34 constitute a first drive direction converting section 35 that converts the rotational movement of the cam 30 into the swinging movement of the lever 33.

A tie rod 40 is arranged horizontally, and rollers 41 and 42 are pivotally attached to both ends of the tie rod. One roller 41 is connected to the groove 3 formed at the lower end of the lever 33.
6, and the other roller 42 is connected to another lever 4
It fits into the groove 44 of No. 3. When the lever 33 swings, the tie rod 40 reciprocates in the horizontal direction, and the lever 43
swings in the direction of arrow C around pin 45.

50 is a pulse motor disposed above the tie loft 40, 51 is its support bracket, 52 is a coupling, 53
is a screw rod, and the tie loft 40 is moved up and down in the vertical direction d by driving the pulse motor 50. This motor 50 is automatically controlled by a computer 59. Data on the thickness of each electronic component to be sequentially mounted on the board 6 is input into the computer 59 in advance, and the motor 50 is controlled by transmitting pulses based on the data. The tie rod 40 is moved up and down by the motor 50, and the movement is transmitted to the lifting shaft 63 of the transfer head 7.

Reference numerals 54 and 55 denote guide members for guiding the vertical movement of the tie rod 40 (see FIG. 1), 56 a guide member for guiding horizontal reciprocation, and 57 a support member for the guide members 55 and 56.

Reference numeral 60 denotes a second driving direction converting section, which includes a guide body 61 erected on the bottom surface of the main body box 1, a slider 62 that moves up and down along the guide body 61, and the like. Grooves are formed on both sides of the slider 62, one groove holds the roll 46 of the lever 43, and the other groove holds the roll attached to the upper part of the lifting shaft 63 of the transfer head 7. 64 are fitted.

65 is a ring guide for another roll 64 attached to the upper part of the shaft 63, and 66 is a lifting guide for the shaft 63. FIG. 4 schematically shows the transmission mechanism from the drive section 21 to the lifting shaft 63, and the operation will be explained next with reference to this figure.

Due to the continuous rotation of the cam 30, the lever 33 swings in the direction of arrow a, and the tie rod 40 reciprocates in the horizontal direction. Then, the other lever 43 swings in the direction of arrow C, the slider 62 moves up and down along the guide body 61, and therefore the transfer head 7 connected to the slider 62 via the shaft 63 also moves up and down.

Here, as shown by the solid line in the figure, when the tie rod 40 is in a high position and the roll 41 has entered deeply into the groove 36 of the lever 33, the tie rod 40 is reciprocated by the lever 33, and its horizontal The stroke L in the direction is short, so the swing of the other lever 43 is also small, and the vertical stroke S1 of the transfer head 7 is short. On the other hand, when the tie rod 40 is at a low position and the roll 41 has entered the groove 36 shallowly, as shown by the chain line in the figure, the tie rod 40 reciprocates with a large stroke L, and therefore the transfer head The lifting stroke S2 of No. 7 is also long. In this way, the vertical stroke of the transfer head 7 is controlled by the tie rod 40.
Varies depending on the height. Therefore, this device can adjust the stroke size of the transfer head 7 set by the shape of the cam 30 by driving the motor 50 automatically controlled by the computer 59 to change the height of the tie rod 40. I can do it. In this way, the tie rod 40 and the means for vertically moving the tie rod 40 are connected to the first drive direction converting section 3.
5 to the second drive direction converting section 60.

The present apparatus has the above-mentioned configuration, and the operation of the present apparatus will be explained next with reference to FIG.

The transfer head 7 that has adsorbed the electronic component C in the supply section 12
is transported to the mounting section 3 by index rotation of the rotary head 2. A measuring device 80 is disposed in the middle of the conveyance path, and this measures the thickness of the electronic component C attracted to the lower end of the nozzle 8. The measurement signal is input to the computer 59, and is The thickness is corrected by calculating the thickness D1 to Dn of each electronic component 01 to Cn registered in 59 and the average value of these measured values. The pulse motor 50 that drives the transfer head 58 is controlled to adjust the vertical stroke of the transfer head 7.

In FIG. 7, SL, S2...Sn indicate lifting strokes based on the thicknesses D1 to Dn registered in the computer 59 in advance.

As shown in this figure, due to variations in the thickness of electronic components C1 to Cn, stroke errors ΔSl and ΔS
2...ΔSn exists.

However, these errors ΔS1 to ΔSn are based on the thickness D registered in the computer 59 by measuring the thickness of each of the electronic components 01 to Cn by the measuring device 80 as described above.
1 to Dn and adjust the vertical stroke of the transfer head 7 based on this correction value, so that the nozzle 8 reliably picks up the electronic component C.

Of course, if the vertical stroke of the transfer head 7 due to the variation in the thickness of the electronic component C is corrected in this way, the vertical stroke of the transfer head 7 in the mounting section 3 will also be appropriate, and the electronic component C attracted to the nozzle 8 will be corrected. can be reliably mounted on the board 6. Note that the present invention is not limited to the above-mentioned embodiments, and can also be applied to an electronic component mounting apparatus that mounts an electronic component on a board while moving a transfer head in the X and Y directions, for example.

(Effects of the Invention) As described above, the present invention includes a supply section for electronic components and a mounting section for mounting the electronic components on a board, and in the supply section, the nozzle of the transfer head is raised and lowered to remove the nozzle. In an electronic component mounting apparatus that picks up electronic components at the lower end and transfers and mounts them onto the board, a measuring device is disposed between the supplying section and the mounting section, and the measuring device allows the electronic components to be picked up by the nozzle. The thickness of the electronic components is measured, the average value of the thickness of the electronic components is calculated by a computer, and the vertical stroke of the nozzle is adjusted based on this average value. The vertical stroke of the nozzle is corrected in response to variations in the height, and one electronic component in the supply section can be reliably picked up and mounted on the mounting section.

[Brief explanation of drawings]

The top view and FIG. 3 are a plan view and a front view of the rotary head. 3... Loading section 6... Board 7... Transfer head 8... Nozzle 12... Supply section 59... Computer 80... Measuring device

Claims (1)

[Claims] The electronic component supply unit includes a supply unit for electronic components and a mounting unit for mounting the electronic components on a board, and in the supply unit, a nozzle of a transfer head is raised and lowered to adsorb the electronic component to the lower end of the nozzle,
In the electronic component mounting apparatus for transferring and mounting on the board, a measuring device is disposed between the supply section and the mounting section,
This measuring device measures the thickness of the electronic components attracted to the nozzle, calculates the average value of the thickness of the electronic components using a computer, and adjusts the vertical stroke of the nozzle based on this average value. An electronic component mounting device characterized by: