JP2701831B2 - 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 for mounting an electronic component on a substrate.

[0002]

2. Description of the Related Art As an electronic component mounting apparatus for mounting electronic components such as ICs and LSIs on a substrate at high speed, a device equipped with a rotary head is known. FIG. 6 is a plan view of a rotary head of a conventional electronic component mounting apparatus.
Is a rotary head, on the lower surface of which a number of mounting heads 101 are juxtaposed along the circumferential direction. Below the rotary head 100, a supply unit 102 for electronic components such as trays and tapes, and a mounting unit 1 composed of an XY table
03 is provided. In this electronic component mounting apparatus, after the mounting head 101 is moved up and down in the supply unit 102 to suck the electronic component C, the mounting head 101 is intermittently rotated in the N direction so that the mounting head 101 is mounted on the mounting unit 10.
3, the mounting head 101 is moved up and down again, and the electronic component C is mounted on the mounting portion 103.
4

FIG. 7 is a front view of a driving mechanism of a mounting head of a conventional electronic component mounting apparatus, and FIG. 8 is a front view of a nozzle of the electronic component mounting apparatus. In FIG. 7, reference numerals 105 and 106 denote a drive unit box and a motor for rotating the rotary head 100 in the above-described N direction.
Reference numeral 8 denotes a first member including a cam 108a and a cam follower 108b.
, 109 and 110 are transmission levers and tie rods, 111 is a lever, and 112 is a slider 11.
A driving direction conversion unit 2a or the like, 113 is a shaft of the mounting head 101, and 114 is a nozzle protruding below the mounting head 101.

Next, the operation of the electronic component mounting apparatus will be described. When the motor 106 is driven to rotate the cam 108a, the cam follower 108b moves up and down, and the lever 109 swings around the pin 109a in the direction of arrow a. Then, the tie rod 110 reciprocates in the horizontal direction b, and the lever 11
1 also swings around the pin 111a in the direction of arrow c, and the slider 112a moves up and down. Then, the shaft 113 also moves up and down so that the nozzle 114 moves up and down, and the electronic component C adsorbed to the lower end of the nozzle 114 is mounted on the substrate 104. This operation is the same when the electronic component C is taken up by moving the nozzle 114 of the mounting head 101 up and down in the supply unit 102.

[0005]

The up-and-down stroke of the nozzle 114 of the conventional electronic component mounting apparatus is the same as that of the cam 10.
The cam 108a is designed so that a desired elevating stroke can be obtained. This elevating stroke is set as an average stroke corresponding to the average value of the thickness of the electronic component to be mounted. Therefore, in this kind of conventional electronic component mounting apparatus, when changing the elevating stroke of the nozzle of the mounting head, it is necessary to design and manufacture a cam capable of obtaining a desired average stroke each time and replace it with the cam set in the apparatus. did not become. However, designing and manufacturing the cam requires considerable labor and cost, and the replacement of the cam is extremely troublesome, and the operation of the apparatus must be stopped during the replacement.

Further, in the conventional electronic component mounting apparatus, since the elevating stroke set to the above-mentioned average stroke is constant, the elevating stroke can be freely adjusted according to a change in the thickness of the electronic component during work. Could not be done. Therefore, when the thickness of the electronic component is larger than the average value, the vertical stroke (average stroke Sm) becomes too large as shown in FIG. There is a possibility that the portion may strongly hit the upper surface of the electronic component C and break it. Such a trouble occurs in both the supply unit 102 and the mounting unit 103.

On the other hand, if the thickness of the electronic component is smaller than the average value, the up-and-down stroke is too short. A gap t is generated between the lower end and the upper surface of the electronic component C, and the electronic component C cannot be reliably sucked (see FIG. 8B).
In No. 03, even if the mounting head 101 is lowered, there is a gap t between the electronic component C and the substrate 104, and the electronic component C is released from the suction in a state of being suspended in the air. There is a problem that the robot naturally falls on the 104 and cannot land at a correct position in a correct posture (see FIG. 8C). As understood from the above description, in this type of device,
It is a very important task to easily and properly set the elevating stroke of the mounting head.

Another means is known as a means for setting the elevating stroke of the mounting head. This means is a means for substantially adjusting the up / down stroke of the mounting head by raising and lowering a mounting portion composed of an XY table or the like according to the thickness of the electronic component. However, this means is difficult to respond to the change in the thickness of the electronic component in detail, and merely responds roughly to the change in the thickness of the electronic component by simply setting two levels of height, There were many mounting errors on the substrate. Further, since this kind of supply unit is generally fixed on a table fixed on the floor, it is practically impossible or difficult to raise and lower like a mounting unit. It is at least generally inapplicable to means for adjusting the stroke. Even if the supply unit is arranged so as to be able to move up and down so as to adjust the elevating stroke of the mounting head, in this case, the supply unit and the mounting unit must be provided with these lifting means and control means separately. Therefore, the device becomes extremely complicated. The problem of such a stroke of raising and lowering the nozzle is not limited to the above-mentioned electronic component mounting apparatus having a rotary head, and for example, the mounting head described in JP-A-63-14500 is horizontally moved in the X direction and the Y direction. Let me
An electronic component mounting apparatus of a type in which an electronic component provided in an electronic component supply unit is mounted on a substrate positioned at a mounting unit has also been found.

Accordingly, the present invention provides a method for mounting an electronic component capable of taking up an electronic component from a supply portion or mounting the electronic component on a substrate with an appropriate nozzle up / down stroke in response to a change in the thickness of the electronic component. The aim is to provide a method.

[0010]

According to a first aspect of the present invention, a nozzle of a mounting head is moved up and down in a supply section of an electronic component to mount an electronic component on a lower end portion of the nozzle, and then the mounting head is mounted on the electronic component. In the electronic component mounting method in which the electronic component is mounted on the substrate by moving the nozzle up and down again at the mounting portion, the nozzle of the mounting head mounts the reference electronic component on the substrate of the mounting portion. The lifting stroke at the time of performing the above is set as a reference stroke, and a correction value of the lifting stroke based on the difference between the thickness of the reference electronic component and other electronic components is calculated by a computer as the rotation speed of the nozzle lifting motor. The lifting stroke of the nozzle when the electronic component is mounted on the substrate is set by adding the correction value to the reference stroke.

According to a second aspect of the present invention, the mounting head nozzle is moved up and down in the electronic component supply section to mount the electronic component on the lower end of the nozzle, and then the mounting head is moved to the electronic component mounting section. In the electronic component mounting method in which the electronic component is mounted on the substrate by moving the nozzle up and down again in the mounting portion, the vertical movement stroke when the nozzle of the mounting head takes up the standard electronic component from the supply portion is determined as a reference. A stroke, and a computer calculates a correction value of a lifting stroke based on a difference in thickness between the reference electronic component and another electronic component as a rotation speed of a nozzle lifting motor, and supplies the other electronic component to the supply unit. The up-and-down stroke of the nozzle at the time of take-up is set by adding the correction value to the reference stroke.

[0012]

According to the first aspect of the present invention, assuming that the up / down stroke of the nozzle when the reference electronic component is mounted on the substrate is the reference stroke, the other electronic components have the same reference stroke. By adding a correction value based on the difference in the thickness of the electronic component, the vertical stroke can be accurately set.

According to the second aspect of the present invention, assuming that the up / down stroke of the nozzle when the reference electronic component is taken up is the reference stroke, the other electronic components have the thickness of the electronic component as the reference stroke. By adding a correction value based on the difference in height, the up / down stroke can be accurately set.

(Embodiment 1) FIG. 1 is a perspective view of an electronic component mounting apparatus according to an embodiment of the present invention, FIG. 2 is a front view of a driving mechanism of the mounting head, and FIG. 3 is a plan view of the rotary head. FIG. 4 is a simplified front view of the driving mechanism, and FIG. 5 is a front view of the nozzle.

In FIG. 1, reference numeral 1 denotes a main body box, 2 denotes a rotary head rotatably mounted on a lower portion of the main body box 1, and 3 denotes a mounting portion of an electronic component comprising an X table 4 and a Y table 5. Reference numeral 6 denotes a mounting portion 3 and a clamp portion 1
0 is a substrate set by clamping with 0
Is slid in an arbitrary direction J by sliding of the X table 4 and the Y table 5, and is positioned at a predetermined position. On the lower surface of the rotary head 2, a number of mounting heads 7 are arranged side by side along the circumferential direction, and each mounting head 7 has a nozzle 8 projecting downward (see also FIG. 2). . Reference numeral 9 denotes a spring provided to allow a slight vertical movement of the nozzle 8. The nozzle 8 sucks an electronic component at its lower end by vacuum pressure.

FIG. 3 is a plan view of the rotary head 2. Numeral 12 denotes a supply section of the electronic component C provided on the opposite side of the mounting section 3, and the rotary head 2 intermittently rotates as described later. Then, the electronic component C of the supply unit 12 is transported to the substrate 6 and mounted on the substrate 6 by the elevating operation of the nozzle 8 of the mounting head 7. Reference numeral 13 denotes a recognition device provided between the supply unit 12 and the mounting unit 3, which comprises an optical system.
The twist (horizontal rotation angle) of the electronic component C sucked at the lower end of the nozzle 8 with respect to the axis of the nozzle 8 is detected, and a motor 14 (see FIG. ) To rotate the mounting head 7 in the H direction (FIG. 3) about its axis through the belt 15, the spline shaft 16, the gears 17, 18, and the like.
The torsion of the electronic component C sucked by the nozzle 8 is corrected. Next, the drive mechanism of the mounting head 7 will be described with reference to FIGS.

Reference numeral 20 denotes a drive unit box disposed immediately above the rotary head 2 in the main body box 1, reference numeral 21 denotes a drive unit of the drive unit box 20, and reference numeral 22 denotes a support frame. The rotary head 2 is attached to the output shaft 23a of the drive unit box 20.
The rotary head 2 is intermittently rotated horizontally by the driving of the driving unit 21. The driving unit 21 is a pulse motor, and its power is transmitted to the mounting head 7 via a transmission path described below, and moves the nozzle 8 of the mounting head 7 up and down at a predetermined stroke. 25a is a pulley attached to another output shaft 23b of the drive unit box 20, 25b is another pulley, and 26 is a pulley 25
A timing belt tuned to a and 25b, and 27 is a rotating shaft of the pulley 25b. At both ends of the rotating shaft 27, the nozzles 8 of the mounting head 7 are provided at two places, the supply unit 12 and the mounting unit 3.
The two cams 30, 30 are mounted to raise and lower the cam. Since the raising / lowering mechanism of the nozzle 8 of the mounting head 7 in the supply unit 12 and the mounting unit 3 is the same, the driving mechanism of the mounting unit 3 will be described below with reference to FIG.

Reference numeral 31 denotes a cam follower which comes into contact with the peripheral surface of the cam 30, and is pivotally mounted on a key-shaped lever 33. 3
Reference numeral 4 denotes a coil spring for pressing 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 has an arrow a about the pin 32.
Rocks in the direction. That is, these members 30 to 34
Constitutes a first drive direction converter 35 that converts the rotational movement of the cam 30 into the swing movement of the lever 33.

Reference numeral 40 denotes a tie rod which is disposed horizontally, and rollers 41 and 42 are axially mounted on both ends thereof. One roller 41 fits into a groove 36 formed at the lower end of the lever 33, and the other roller 42 fits into a groove 44 of another lever 43. Lever 33
Swings, the tie rod 40 reciprocates in the horizontal direction b, and the lever 43 swings about the pin 45 in the direction of arrow c.

Reference numeral 50 denotes a pulse motor disposed above the tie rod 40, 51 denotes a support bracket thereof, 52 denotes a coupling, and 53 denotes a screw rod. When the pulse motor 50 is driven, the tie rod 40 moves up and down in the vertical direction d. . The pulse motor 50 is automatically controlled by a computer 59. Reference numerals 54 and 55 denote guide members (see FIG. 1) for guiding the vertical movement of the tie rod 40, reference numeral 56 denotes a guide member for guiding horizontal reciprocation, and reference numeral 57 denotes a support member for the guide members 55 and 56.

Reference numeral 60 denotes a second driving direction changing portion, which comprises a guide member 61 erected on the bottom surface of the main body box 1, a slider 62 moving up and down along the guide member 61, and the like. Grooves are formed on both sides of the slider 62, and a roll 46 of the lever 43 is fitted in one groove, and a roll 64 mounted on the upper and lower shaft 63 of the mounting head 7 is fitted in the other groove. I agree. 65 is another roll 64 attached to the upper part of the shaft 63
A ring guide 66 is an elevating guide for the shaft 63. FIG. 4 schematically shows a transmission mechanism from the driving unit 21 to the mounting head 7, and the operation will be described with reference to FIG.

With 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 b. Then, the other lever 43 swings in the direction of arrow c, and the slider 62 moves up and down along the guide body 61. Therefore, the mounting head 7 connected to the slider 62 via the shaft 63 also moves up and down. Here, as shown by the solid line in FIG. 4, when the position of the tie rod 40 is high and the roll 41 is deeply entering the groove 36 of the lever 33, the tie rod 40 is reciprocated by the lever 33 to a small extent, and Direction L is short, the swing of the other lever 43 is also small, and the elevating stroke S1 of the mounting head 7 is short. On the contrary, the position of the tie rod 40 is low as shown by the chain line in FIG.
When the roll 41 enters the groove portion 36 shallowly, the tie rod 40 reciprocates with a large stroke L, and therefore, the vertical stroke S2 of the nozzle 8 of the mounting head 7 is also long. Thus, the lifting stroke of the mounting head 7 changes depending on the height of the tie rod 40. Therefore, the electronic component mounting apparatus changes the height of the tie rod 40 by driving the pulse motor 50 which is automatically controlled by the computer 59, and thereby the stroke of the nozzle 8 of the mounting head 7 set by the shape of the cam 30. The size can be adjusted. That is, the pulse motor 50 is a motor for raising and lowering the nozzle. The change of the height of the tie rod 40 does not need to be performed by the pulse motor 50 or the computer 59, and this will be described later in an embodiment.

As described above, the tie rod 40 and the tie rod 4
The up / down movement means of the first drive direction conversion unit 35
Of the amount of power transmitted to the driving direction converter 60
Is composed. Therefore, as shown in FIG.
Electronic components C1, C2, C3,.
If the rotation amount of the pulse motor 50 according to the magnitude of the thickness D1, D2, D3... Dn (which is known) is programmed in advance and input to the computer 59,
An up / down stroke of the nozzle 8 of the mounting head 7 necessary for appropriately mounting the electronic components C1 to Cn on the substrate 6 can be easily obtained. Needless to say, in the supply unit 12, a vertical stroke required to suck the electronic component to the lower end of the nozzle 8 can be obtained in a similar manner. Next, a series of operation procedures by the present apparatus will be further described with reference to FIG.

In the work schedule, the first electronic component C1 (see FIG. 5A) is mounted on the substrate 6 by moving the nozzle 8 of the mounting head 7 up and down. In this case, the pulse motor 5 that raises and lowers the tie rod 40 so that the electronic component C1 having the thickness D1 is properly formed on the substrate 6.
0 is controlled, and the control value at that time is detected and stored in the computer 59. By such teaching means, the elevating stroke for mounting the electronic component C1 having the thickness D1 on the substrate 6 is set as the reference stroke S1. The other electronic components C mounted on the substrate 6 after the second
The lifting strokes S2 to Sn of 2 to Cn are set by adding the difference ΔD2 to ΔDn of the thickness with the first electronic component C1 as a correction value of the reference stroke S1. That is, the first electronic component C1 is different from the other electronic components C2 to C2.
It serves as a reference electronic component for determining the up / down stroke of the nozzle 8 when Cn is mounted on the substrate 6.

That is, since the thicknesses D to Dn of the second and subsequent electronic components C2 to Cn shown in FIGS. 5B to 5E are known, the thickness of the first electronic component C1 as the reference electronic component is known. The thickness differences ΔD2 to ΔDn from the thickness D1 are also known. Therefore, each difference ΔD2 to ΔDn is calculated and calculated in advance by the computer 59 as a function of the rotation speed of the pulse motor 50, and a predetermined pulse signal is sent from the computer 59 to control the rotation speed of the pulse motor 50. For example, the nozzles 8 of the mounting head 7 can be moved up and down by the elevating strokes S2 to Sn necessary for properly mounting the electronic components C2 to Cn on the substrate 6. A remarkable advantage of this means is that the pulse motor 50 is automatically controlled by the computer 59 while the cam 30 is continuously rotated without stopping the operation of the apparatus, so that the lifting stroke of the nozzle 8 of the mounting head 7 can be freely adjusted. The advantage is that it is adjustable, and this advantage is extremely important for such an electronic component mounting apparatus in which high speed and accuracy of operation are emphasized.

The above operation has been described by taking as an example the case where the electronic component is mounted on the substrate 6 in the mounting unit 3. However, the same applies to the case where the electronic component of the supply unit 12 is taken up by moving the nozzle 8 of the mounting head 7 up and down. It is. That is, in this case as well, firstly, a rising / falling stroke at the time of taking up the reference electronic component from the supply unit 12 is detected, and this rising / falling stroke is set as the reference stroke, and the lifting / lowering necessary for the take-up of the second and subsequent electronic components is performed. The stroke may be controlled by controlling the pulse motor 50 based on a difference in thickness from the first electronic component.

[0027]

According to the present invention, a reference electronic component is taken up from a supply unit or a vertical stroke of a nozzle when the electronic component is mounted on a substrate is set as a standard stroke. Since the vertical stroke is set by adding a correction value based on the difference in the thickness of the electronic components, electronic components of various thicknesses are surely attracted to the lower end of the nozzle of the mounting head and taken up. Can be mounted on a substrate.

[Brief description of the drawings]

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

FIG. 2 is a front view of a driving mechanism of a mounting head of the electronic component mounting apparatus according to the embodiment of the present invention;

FIG. 3 is a plan view of a rotary head of the electronic component mounting apparatus according to one embodiment of the present invention;

FIG. 4 is a simplified front view of a drive mechanism of the electronic component mounting apparatus according to one embodiment of the present invention.

FIG. 5 is a front view of a nozzle of the electronic component mounting apparatus according to the embodiment of the present invention.

FIG. 6 is a plan view of a rotary head of a conventional electronic component mounting apparatus.

FIG. 7 is a front view of a driving mechanism of a mounting head of a conventional electronic component mounting apparatus.

FIG. 8 is a front view of a nozzle of a conventional electronic component mounting apparatus.

[Explanation of symbols]

 Reference Signs List 3 mounting part 6 substrate 7 mounting head 8 nozzle 12 supply part 21 pulse motor 30 cam 31 cam follower 40 tie rod 50 pulse motor (nozzle elevating motor) 59 computer C1 reference electronic parts C2 to Cn other electronic parts

Claims (2)

(57) [Claims] 1. A mounting head nozzle is moved up and down in a supply section of an electronic component to mount an electronic component on a lower end portion of the nozzle. Then, the mounting head is moved to a mounting portion of the electronic component, and then the mounting head is re-mounted in the mounting portion. In a mounting method of an electronic component in which an electronic component is mounted on a substrate by raising and lowering a nozzle, a lifting stroke when the nozzle of the mounting head mounts the reference electronic component on the substrate of the mounting portion is defined as a reference stroke, and The correction value of the vertical stroke based on the difference between the thickness of the reference electronic component and the other electronic component is calculated and calculated by a computer as the number of revolutions of the nozzle lifting / lowering motor, and is used when the other electronic component is mounted on the substrate. A method of mounting an electronic component, wherein the up / down stroke of the nozzle is set by adding the correction value to the reference stroke. 2. A mounting head nozzle is moved up and down in an electronic component supply section to mount an electronic component on a lower end portion of the nozzle. Then, the mounting head is moved to a mounting section of the electronic component, and the mounting section is again moved to the mounting section. In a mounting method of an electronic component in which an electronic component is mounted on a substrate by raising and lowering a nozzle, a lifting stroke when a nozzle of the mounting head takes up a reference electronic component from the supply unit is set as a reference stroke, and When a computer calculates a correction value of a lifting stroke based on a difference in thickness between a reference electronic component and another electronic component as a rotation speed of a nozzle lifting / lowering motor, and takes up the other electronic component from the supply unit. Wherein the lift stroke of the nozzle is set by adding the correction value to the reference stroke. Implementation of the goods.