JPH08288698A - Mounting method for electronic component - Google Patents

Abstract

PURPOSE: To suitable take up or mount an electronic component by using the elevational stroke of a nozzle at the time of mounting a reference electronic component on a board as a reference stroke, and setting the elevational stroke by adding a correction value to the difference of the thickness of the component to the reference stroke for the other electronic component. CONSTITUTION: The elevational stroke when a reference electronic component is mounted on the board 6 of an electronic component mounting unit 3 by the nozzle 8 of a mounting head 7 is used as a reference stroke, the correction value of the stroke based on the difference of the thicknesses of the reference component, the other electronic component is used as the number of revolutions of a nozzle elevation motor 50 and calculated by a computer 59 to be obtained. The stroke of the nozzle 8 when the other component is mounted on the board 6 is added to the correction value at the reference stroke to be set. Thus, the component can be taken up from the supply unit or mounted at the board 6 by the suitable stroke of the nozzle 8 corresponding to the change in the thickness of the component.

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 electronic components on a board.

[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 a high speed, there is known an electronic component mounting apparatus. FIG. 6 is a plan view of a rotary head of a conventional electronic component mounting apparatus.
Is a rotary head, and a plurality of mounting heads 101 are arranged in parallel on the lower surface thereof 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 including an XY table.
03 is provided. In this electronic component mounting apparatus, the mounting head 101 is moved up and down in the supply unit 102 to adsorb the electronic component C, and then the rotary head 100 is intermittently rotated in the N direction to mount the mounting head 101 on the mounting unit 10.
Substrate 10 on which the electronic component C is set on the mounting portion 103 by moving the mounting head 101 up and down again.
It is designed to be mounted on the 4.

FIG. 7 is a front view of a drive 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, 105 and 106 are a drive unit box and a motor for rotating the rotary head 100 in the N direction, 107 is a transmission belt, and 10 is a drive belt.
8 is a first composed of a cam 108a and a cam follower 108b.
Drive direction changing portion, 109 and 110 are transmission levers and tie rods, 111 is a lever, and 112 is a slider 11.
2a and the like, a driving direction changing portion, 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 and the cam 108a rotates, the cam follower 108b moves up and down, and the lever 109 swings around the pin 109a in the arrow a direction. Then, the tie rod 110 reciprocates in the horizontal direction b, and the lever 11
1 also swings in the direction of arrow c around the pin 111a, and the slider 112a moves up and down. Then, the shaft 113 also moves up and down, 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 nozzle 114 of the mounting head 101 is moved up and down in the supply unit 102 to take up the electronic component C.

[0005]

The ascending / descending stroke of the nozzle 114 of the conventional electronic component mounting apparatus is as follows.
It is constant due to the shape of 8a, and the cam 108a is designed to obtain the desired lifting stroke. 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 type of conventional electronic component mounting apparatus, when changing the lifting stroke of the nozzle of the mounting head, a cam that obtains the desired average stroke must be designed and manufactured each time and replaced with the cam set in the apparatus. did not become. However, the design and manufacture of the cam requires considerable labor and cost, and the replacement work of the cam is very troublesome, and there is a problem that the operation of the device must be stopped during the replacement.

Further, in the conventional electronic component mounting apparatus, since the lifting stroke set to the average stroke is constant, it is possible to freely adjust the lifting stroke according to the change in the thickness of the electronic component during the work. Was not possible. Therefore, when the thickness of the electronic component is thicker than the average value, the lifting stroke (average stroke Sm) becomes too large as shown in FIG. 8A, and therefore, when the mounting head 101 descends, the lower end of the nozzle 114 is lowered. There is a risk that the portion may hit the upper surface of the electronic component C strongly and destroy it. Such trouble occurs in both the supply unit 102 and the mounting unit 103.

On the contrary, when the thickness of the electronic component is thinner than the average value, the lifting stroke is too short, and therefore, even when the mounting head 101 is lowered in the supply unit 102, the nozzle 114 is There is a gap t between the lower end and the upper surface of the electronic component C, and the electronic component C cannot be reliably adsorbed (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 while floating in the air. There was a problem that the ball naturally dropped onto 104 and could not land in the correct position with the correct posture (see FIG. 8C). As can be understood from the above description, in this type of device,
A simple and proper setting of the lifting stroke of the mounting head is a very important issue.

Another means is known as means for setting the lifting stroke of the mounting head. This means is a means for substantially adjusting the elevating stroke of the mounting head by elevating and lowering the mounting portion such as an XY table according to the thickness of the electronic component. However, it is difficult for this means to finely respond to the change in the thickness of the electronic component, and simply to set the two stages of high and low to roughly respond to the change in the thickness of the electronic component. There were many mounting mistakes on the board. In addition, since this kind of supply unit is generally fixed to a table fixed on the floor, it is practically impossible or difficult to raise and lower like a mounting unit, and therefore such a means can be moved up and down in the supply unit. It is at least not generally applicable to the means for adjusting the stroke. Even if the supply unit is arranged to be movable up and down so that the lifting stroke of the mounting head can be adjusted, 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. Such a problem of the lifting stroke of the nozzle is not limited to the electronic component mounting apparatus having the rotary head, and the mounting head described in, for example, Japanese Patent Laid-Open No. 63-14500 is horizontally moved in the X direction and the Y direction. Let me
The same can be seen in the electronic component mounting apparatus of the type in which the electronic component provided in the electronic component supply unit is mounted on the substrate positioned in the mounting unit.

Therefore, according to the present invention, in response to a change in the thickness of the electronic component, the electronic component can be taken up from the supply section or mounted on the substrate by an appropriate stroke for raising and lowering the nozzle. The purpose is to provide a method.

[0010]

According to a first aspect of the present invention, a nozzle of a mounting head is raised and lowered in an electronic component supply section 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 a mounting method of an electronic component in which the electronic component is mounted on the board by moving the nozzle to the mounting portion and raising and lowering the nozzle in the mounting portion again, the nozzle of the mounting head mounts the reference electronic component on the substrate of the mounting portion. When the lifting stroke is set as a reference stroke, and a correction value of the lifting stroke based on the difference in thickness between the reference electronic component and other electronic components is calculated as a rotation speed of the nozzle lifting motor by a computer, and The ascending / descending stroke of the nozzle when the electronic component (1) 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 nozzle of the mounting head is moved up and down in the electronic component supply unit to mount the electronic component on the lower end of the nozzle, and then the mounting head is moved to the electronic component mounting portion. In an electronic component mounting method in which the electronic component is mounted on the board by elevating the nozzle again in the mounting unit, the lifting stroke when the nozzle of the mounting head takes up the reference electronic component from the supply unit is used as a reference. A stroke, and a correction value of a lifting stroke based on a difference in thickness between the reference electronic component and another electronic component is calculated as a rotation speed of a nozzle lifting motor by a computer to obtain the other electronic component. The up-and-down stroke of the nozzle when taking up from is set by adding the correction value to the reference stroke.

[0012]

According to the first aspect of the present invention, when the reference stroke is the ascending / descending stroke of the nozzle when the reference electronic component is mounted on the substrate, the reference stroke is applied to other electronic components. By adding a correction value due to the difference in the thickness of the electronic component to, it is possible to accurately set the lifting stroke.

According to the second aspect of the present invention, if the lifting stroke of the nozzle at the time of taking up the reference electronic component is used as the reference stroke, for other electronic components other than that, the thickness of the electronic component is added to this reference stroke. By adding a correction value based on the difference in height, the lifting stroke can be set accurately.

(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 drive 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 drive mechanism, and FIG. 5 is a front view of the nozzle.

In FIG. 1, reference numeral 1 is a main body box, 2 is a rotary head rotatably mounted on the lower portion of the main body box 1, and 3 is an electronic component mounting portion including an X table 4 and a Y table 5. 6 is a mounting part 3 and a clamp part 1
Substrate 6 clamped by 0 and set, substrate 6
Is slid in an arbitrary direction J by the sliding of the X table 4 and the Y table 5, and is positioned at a predetermined position. A large number of mounting heads 7 are arranged in parallel on the lower surface of the rotary head 2 along the circumferential direction thereof, and each mounting head 7 is provided with a nozzle 8 projecting downward (see also FIG. 2). . Reference numeral 9 is 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. Reference numeral 12 is a supply portion for the electronic component C disposed on the opposite side of the mounting portion 3, and as will be described later, an intermittent rotation operation of the rotary head 2 is performed. By moving the nozzle 8 of the mounting head 7 up and down, the electronic component C of the supply unit 12 is transported to the substrate 6 and mounted on it. Reference numeral 13 denotes a recognition device disposed between the supply unit 12 and the mounting unit 3, which is composed of an optical system and includes a nozzle 8
The twist (horizontal rotation angle) of the electronic component C attracted to the lower end of the nozzle 8 with respect to the axis of the nozzle 8 is detected, and the detection signal outputs the motor 14 mounted on the upper surface of the rotary head 2 (see FIG. 2). ) Is driven, and the mounting head 7 is rotated in the H direction (FIG. 3) about its axis through the belt 15, the spline shaft 16, the gears 17 and 18, and the like.
The twist of the electronic component C attracted to the nozzle 8 is corrected. Next, the drive mechanism of the mounting head 7 will be described with reference to FIGS. 1 and 2.

Reference numeral 20 is a drive unit box disposed directly above the rotary head 2 in the main body box 1, 21 is a drive unit of the drive unit box 20, and 22 is 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 drive of the drive unit 21. The drive unit 21 is a pulse motor, the power of which is transmitted to the mounting head 7 via a transmission path described below, and raises and lowers the nozzle 8 of the mounting head 7 in 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.
The timing belt is tuned to a and 25b, and 27 is the rotation shaft of the pulley 25b. At both ends of the rotary shaft 27, the nozzle 8 of the mounting head 7 is provided at two locations, the supply section 12 and the mounting section 3.
Two cams 30, 30 are mounted to raise and lower the. Since the lifting mechanism of the nozzle 8 of the mounting head 7 in the supply unit 12 and the mounting unit 3 is the same, the drive mechanism on the mounting unit 3 side will be described below with particular reference to FIG.

Reference numeral 31 is a cam follower that comes into contact with the peripheral surface of the cam 30, and is pivotally attached to a key-shaped lever 33. Three
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 moves the arrow a around the pin 32.
Rocks in the direction. That is, these members 30 to 34
Constitute a first drive direction conversion portion 35 that converts the rotational movement of the cam 30 into the swing movement of the lever 33.

Reference numeral 40 is a tie rod, which is arranged horizontally, and rollers 41 and 42 are axially attached to both ends thereof. One roller 41 is fitted in the groove 36 formed in the lower end of the lever 33, and the other roller 42 is fitted in the groove 44 of the other lever 43. Lever 33
When oscillates, the tie rod 40 reciprocates in the horizontal direction b, and the lever 43 oscillates around the pin 45 in the direction of arrow c.

Reference numeral 50 is a pulse motor arranged above the tie rod 40, 51 is a support bracket thereof, 52 is a coupling, 53 is a screw rod, and the tie rod 40 is moved up and down in the vertical direction d by driving the pulse motor 50. . The pulse motor 50 is automatically controlled by the computer 59. 54 and 55 are guide members for guiding the vertical movement of the tie rod 40 (see FIG. 1), 56 is a guide member for guiding horizontal reciprocating movement, and 57 is a support member for the guide members 55, 56.

Reference numeral 60 denotes a second drive direction changing portion, which is composed of a guide body 61 provided upright on the bottom surface of the main body box 1, a slider 62 which moves up and down along the guide body 61, and the like. Grooves are formed on both sides of the slider 62. The roll 46 of the lever 43 is fitted in one groove, and the roll 64 mounted on the upper shaft 63 of the mounting head 7 is fitted in the other groove. I am fit. 65 is another roll 64 mounted on the upper part of the shaft 63
Is a ring guide, and 66 is a lifting guide for the shaft 63. FIG. 4 schematically shows the transmission mechanism from the drive unit 21 to the mounting head 7 described above. Next, the operation will be described with reference to FIG.

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 b with this. 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 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 portion 36 of the lever 33, the tie rod 40 is reciprocated slightly by the lever 33 and its horizontal The stroke L in the direction is short, the swing of the other lever 43 is small, and the lifting stroke S1 of the mounting head 7 is short. On the contrary, as shown by the chain line in FIG. 4, the position of the tie rod 40 is low,
When the roll 41 is shallowly entering the groove portion 36, the tie rod 40 reciprocates with a large stroke L, and therefore the lifting stroke S2 of the nozzle 8 of the mounting head 7 is also long. In this way, the lifting stroke of the mounting head 7 changes depending on the height of the tie rod 40. Therefore, the electronic component mounting apparatus drives the pulse motor 50 automatically controlled by the computer 59 to change the height of the tie rod 40, thereby changing 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 nozzle lifting motor. The height of the tie rod 40 need not be changed by the pulse motor 50 or the computer 59, which will be described later in the embodiment.

In this way, the tie rod 40 and the tie rod 4 are
The vertical movement means of 0 is from the first drive direction conversion unit 35 to the second drive direction conversion unit 35.
Of the amount of transmission transmitted to the drive direction conversion unit 60 of the
Is composed. Therefore, as shown in FIG.
Electronic components C1, C2, C3, ...
If the amount of rotation of the pulse motor 50 according to the magnitude of the thicknesses D1, D2, D3 ... Dn (which is known) is programmed in advance and input to the computer 59,
It is possible to easily obtain the lifting stroke of the nozzle 8 of the mounting head 7 required to properly mount the electronic components C1 to Cn on the substrate 6. Of course, in the supply unit 12, the lifting stroke required to suck the electronic component to the lower end of the nozzle 8 can be obtained in the same manner. Next, a series of work procedures by this 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 placed on the substrate 6.
0 is controlled, and the control value at that time is detected by the computer 59 and stored. With such a teaching means, the lifting stroke for mounting the electronic component C1 having the thickness D1 on the substrate 6 is set as the reference stroke S1. Then, 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 in 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 replaced with the other electronic components C2.
It serves as a reference electronic component for determining the lifting stroke of the nozzle 8 when the 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 first electronic component C1 which is the reference electronic component The thickness difference ΔD2 to ΔDn from the thickness D1 is also known. Therefore, each difference ΔD2 to ΔDn is calculated in advance by the computer 59 as a function of the rotation speed of the pulse motor 50 and programmed, and a predetermined pulse signal is sent from the computer 59 to control the rotation speed of the pulse motor 50. For example, the nozzle 8 of the mounting head 7 can be moved up and down with the lifting strokes S2 to Sn required to properly mount 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, whereby the lifting stroke of the nozzle 8 of the mounting head 7 can be freely set. It is possible to adjust, and such an advantage is extremely important for the electronic component mounting apparatus of this kind in which high speed and accuracy of work are important.

The above operation has been described by taking the case where the electronic component is mounted on the substrate 6 in the mounting portion 3 as an example, but the same is true when the electronic component of the supply portion 12 is moved up and down by moving the nozzle 8 of the mounting head 7. Is. That is, also in this case, the lifting stroke required when the reference electronic component is first taken up from the supply unit 12 is detected, and this lifting stroke is used as the reference stroke, and the lifting and lowering required for taking up the second and subsequent electronic components is performed. The stroke may control the pulse motor 50 based on the difference in thickness from the first electronic component.

[0027]

According to the present invention, the reference stroke is the lifting stroke of the nozzle when the reference electronic component is taken up from the supply section or mounted on the substrate, and other electronic components are set to this reference stroke. Since the elevation stroke is set by adding the correction value due to the difference in the thickness of the electronic components, the electronic components with various thicknesses are surely adsorbed to the lower end of the nozzle of the mounting head to take up. , Can be mounted on a substrate.

[Brief description of 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 mounting head driving mechanism 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 the embodiment of the present invention.

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

FIG. 5 is a front view of the 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 drive 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]

 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 lifting motor) 59 computer C1 standard electronic parts C2-Cn other electronic parts

Claims (2)

[Claims] 1. 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, and then the mounting head is moved to an electronic component mounting portion, and again at this mounting portion. In a mounting method of an electronic component in which an electronic component is mounted on a substrate by moving a nozzle up and down, a nozzle of the mounting head uses a lifting stroke when mounting a reference electronic component on the substrate of the mounting portion as a reference stroke, and When the correction value of the lifting stroke based on the difference in thickness between the reference electronic component and the other electronic component is calculated by the computer as the rotation speed of the nozzle lifting motor, and when the other electronic component is mounted on the substrate, An electronic component mounting method, wherein an elevation 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, and then the mounting head is moved to an electronic component mounting portion, and the mounting portion is again mounted. In a mounting method of an electronic component in which a nozzle is moved up and down to mount an electronic component on a substrate, 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 the correction value of the lifting stroke based on the difference in thickness between the reference electronic component and the other electronic component is calculated by the computer as the rotation speed of the nozzle lifting motor, and the other electronic component is taken up from the supply unit. The electronic device is characterized in that the up / down stroke of the nozzle is set by adding the correction value to the reference stroke. Implementation of the goods.