JP3149796B2 - Electronic component mounting equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic component mounting apparatus for transferring and mounting electronic components on a substrate.

[0002]

2. Description of the Related Art An electronic component mounting apparatus for mounting an electronic component (hereinafter, referred to as a chip) on a substrate such as a lead frame or a printed circuit board picks up a chip provided in a chip supply unit such as a wafer by vacuum suction to a collet. And mounted on a substrate (for example, Japanese Patent Application Laid-Open
No. 15099).

FIG. 6 is a sectional view of a collet elevating mechanism provided in a transfer head of a conventional electronic component mounting apparatus,
The collet elevating mechanism described in the above-mentioned Japanese Patent Application Laid-Open No. 1-215099 or the like is shown for easy understanding. In the figure, reference numeral 1 denotes an elevating shaft, at the lower end of which a collet 2 is provided. The collet 2 holds the chip 3 by vacuum suction, and mounts the chip 3 on the substrate 17 by performing a lifting operation above the substrate 17. In FIG. 6,
The mechanism of the vacuum suction system is omitted.

Reference numeral 4 denotes a holder. The elevating shaft 1 is inserted into a sleeve 5 mounted on the holder 4 so as to be able to move up and down. The upper part of the sleeve 5 is inserted into the outer cylinder 6. A washer 7 is provided at the upper end of the elevating shaft 1, and the washer 7 lands on the outer cylinder 6. The outer cylinder 6 is repelled upward by a first spring 8. A pin 9 projects laterally from the washer 7, and the pin 9 and the holder 4 are connected by a second spring 10. The second spring 10
The lifting shaft 1 is pushed downward.

[0005] Reference numeral 11 denotes a shaft, at the lower end of which is provided an engaging element 12 having a U-shaped cross section. The engaging element 12 is engaged with a pin 19 extending from the outer cylinder 6. The shaft 11 is inserted into the sleeve 13 so as to be able to move up and down, and is repelled upward by a third spring 14. A block 15 is provided at the upper end of the shaft 11, and a pressing rod 16 is further provided above the block 15. Elements denoted by reference numerals 11 to 16 constitute pressing means of the elevating shaft 1 and are provided on a mounting stage for mounting the chip 3 on the substrate 17.

In the above configuration, when the elevating shaft 1 moves to the position where the chip 3 is mounted, the pressing rod 16 descends and pushes down the shaft 11 against the spring force of the third spring 14. Then, the outer cylinder 6 descends, and is pulled by the second spring 10, so that the elevating shaft 1 also descends,
As a result, the chip 3 held by the collet 2 is
Lands on the bond 18 applied to the upper surface of the. Next, when the vacuum suction state of the chip 3 is released and the pressing rod 16 is raised, the shaft 11 is raised by the spring force of the third spring 14. Then, the outer cylinder 6 is raised by the spring force of the second spring 8, and the washer 7 and the elevating shaft 1 are pushed up by the outer cylinder 6. As described above, the elevating shaft 1 performs the elevating operation, and the chip 3 is mounted on the substrate 17. The spring force of the first spring 8 is set to be larger than the spring force of the second spring 10.

[0007]

Although the chip size varies depending on the type of the chip 3, it is desirable that the larger the chip size, the more strongly the chip 3 is pressed against the substrate 17 and mounted. However, in the above-described conventional configuration, since the collet 2 presses the chip 3 against the substrate 17 by the spring force of the third spring 10, the third type is changed according to the type change of the chip 3 (that is, the change of the chip size). The adjustment of the spring force of the spring 10 must be performed, and the adjustment of the spring force requires a great deal of labor and time, and the magnitude of the spring force tends to fluctuate due to the individual error of the operator. There was a problem that it was difficult. In particular, in the case of a multi-collet type transfer head having various sizes of collets so as to be able to cope with various kinds of chips, the spring force of the spring must be adjusted every time the collet to be used is changed. The above problems were even more pronounced.

Accordingly, the present invention provides an electronic component mounting apparatus having a transfer head capable of easily changing the magnitude of a pressing force (load) applied from a collet to a chip when the chip is mounted on a substrate. Aim.

[0009]

According to the present invention, there is provided a transfer head of an electronic component mounting apparatus, comprising: a lifting shaft having a collet at a lower end portion for sucking a chip under vacuum; and a holder for holding a plurality of lifting shafts so as to be able to move up and down. A spring for resiliently moving the elevating shaft upward, pressing means for pressing the elevating shaft downward with a predetermined pressing force against the spring force of the spring, and moving the holder relative to the pressing means. Collet selecting means for causing any one of the plurality of elevating shafts to be positioned at an elevating operation position by the pressing means, and changing the pressing force of the pressing means according to the selecting operation of the collet selecting means. A pressing force changing unit , wherein the pressing force changing unit is provided with the pressing unit.
A piston unit that can be pushed down and this piston
The electropneumatic regulator connected to the unit and this piston
Shaft connected to the plunger of the
Controlling the electro-pneumatic regulator and the engaging element engaged with
A control device, wherein the collet is lowered and the chip is
After landing on the board, the piston
Transfer the load applied from the unit to the lifting shaft
Then, the chip was pressed against the substrate .

[0010]

According to the present invention having the above construction, the pressing force can be changed by the pressing force changing means in accordance with the chip size of the chip on which the collet is vacuum-sucked. It can be mounted on a substrate with pressure.

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view of an electronic component mounting apparatus according to one embodiment of the present invention, FIG. 2 is a cross-sectional view of a transfer head of the electronic component mounting apparatus, and FIG. 4 and 5 are partial cross-sectional views of a transfer head of the electronic component mounting apparatus.

First, the overall structure of the electronic component mounting apparatus will be described with reference to FIG. Reference numeral 1 denotes a machine body, in front of which a wafer 2 as a chip supply unit, a chip displacement correcting unit 3 and a positioning unit 4 for a substrate 5 are provided in a horizontal line. Numeral 6 denotes a correction claw, which slides on the displacement correcting unit 3 in the X direction or the Y direction and presses against the chip, thereby correcting the displacement of the chip.

A sliding plate 7 is provided on the front surface of the machine body 1. The sliding plate 7 reciprocates in the lateral direction along the guide rail 8. A drive box 10 is provided on the machine body 1. A groove cam 11 is provided on a side surface of the drive box 10. Reference numeral 13 denotes a drive shaft, a cam follower (not shown) provided at a rear end thereof.
Is a cam groove 1 formed in a ring shape on the side surface of the groove cam 11.
2 is fitted. Therefore, when the drive unit incorporated in the drive box 10 is driven to rotate the groove cam 11, the drive shaft 13 reciprocates in its longitudinal direction.

A horizontal shaft 14 is formed integrally with the drive shaft 13. Three arms 15a, 15b, 15c extend forward from the horizontal shaft 14. A roller 16 is mounted on the distal end of each of the arms 15a to 15c. Key-shaped levers 17a, 17b and 17c are provided in front of the arms 15a to 15c so as to be rotatable up and down around a pin 18. A vertical rod 19 is provided at the tip of each of the levers 17a to 17c. When the drive shaft 13 moves forward, the arms 5a to 15c also move forward, and the upper ends of the levers 17a to 17c are pushed by the roller 16,
The levers 17a to 17c rotate about the pin 18, and the rod 19 descends. When the drive shaft 13 retreats, the levers 17a to 17c are repelled by springs (not shown), rotate in the opposite direction to the previous direction, and the rod 19 rises. As described above, the rod 1 is interlocked with the rotation of the groove cam 11.
9 performs up and down operations. As will be described later, when the rod 19 moves up and down, the nozzle shaft of the transfer head (described later) moves up and down.

In FIG. 1, a rotating shaft 21 extends downward from the drive box 10. A lever 22 is connected to a lower portion of the rotating shaft 21. The lever 2 has a shaft 2
3 are connected. The tip of the shaft 23 is the sliding plate 7
Is joined to. When the drive unit built in the drive box 10 is driven, the rotating shaft 21 rotates horizontally and the lever 22
Rotates 180 ° reciprocally in the horizontal direction about the rotation shaft 21. Thus, the sliding plate 7 connected to the lever 22 via the shaft 23 reciprocates in the lateral direction along the guide rail 8.

A transfer head 40 and a sub-transfer head 70 are mounted on the front surface of the slide plate 7. As described above, when the sliding plate 7 reciprocates in the horizontal direction, the sub-transfer head 70 reciprocates between the wafer 2 and the misalignment correction unit 3,
The chips 9 of the wafer 2 are transferred and mounted on the displacement correcting unit 3. Further, the transfer head 40 reciprocates between the displacement correcting unit 3 and the substrate 5, and transfers and mounts the chip 9 whose positional displacement has been corrected on the displacement correcting unit 3 to the substrate 5.

Next, the structure of the transfer head 40 will be described in detail with reference to FIGS. In FIG. 2, 41
Is a holder having an upper flange 41a and a lower flange 41b. A pipe 42 is inserted into the center of the holder 41. Reference numeral 43 denotes a collet selection motor, which horizontally rotates the holder 41 via a pulley 44, a belt 45, and a pulley 46. 47 is a bearing unit.

Four lifting shafts 48 are inserted into the flange portions 41a and 41b in a vertical posture. A collet 49 is provided at the lower end of the elevating shaft 48.
The elevating shaft 48 and the collet 49 are connected to a pneumatic unit (not shown). When the motor 43 is driven, the holder 41 rotates about the pipe 42 and moves the elevating shaft 48 provided with a desired collet 49 to a use position (a position provided with a pressing means 60 described later). That is, the rotation mechanism of the holder 41 such as the motor 43 serves as a collet selection unit. In the present embodiment, there are four collets 49 around the holder 41, and an optimum collet 49 is selected and used according to the chip size. The elevating shaft 48 is inserted into the sleeve 50 so as to be vertically movable. The upper part of the sleeve 50 is inserted into the outer cylinder 51.
The pipe 42 itself is fixed by a method not shown so as not to rotate.

A spring 52 is interposed between the outer cylinder 51 and the lower flange 41b.
Is popping upwards. 2 and 3, an enlarged portion 53 is formed at an upper portion of the elevating shaft 48.
A pin 54 projects laterally from the enlarged portion 53.

Next, the pressing means 60 of the elevating shaft 48 will be described with reference to FIG. Reference numeral 61 denotes a sleeve standing on the holding frame 55 of the holder 41,
2 is inserted to be able to move up and down. A block 63 is provided at the upper end of the rod 62, and a spring 64 is interposed between the block 63 and the sleeve 61.
The spring 64 has resiliently pushed the rod 62 upward. A piston unit 65 is provided at the lower end of the rod 62. Reference numeral 66 denotes a plunger of the piston unit 65, and an engagement member 67 having a U-shaped cross section is coupled to a lower end of the plunger. An electropneumatic regulator 68 is connected to the piston unit 65. The electropneumatic regulator 68 is controlled by the control device 69. The piston unit 65, the electropneumatic regulator 68, and the control device 69 serve as pressing force changing means for changing the pressing force of the pressing means 60 according to the type of chip.

When the motor 43 is driven to rotate the holder 41 about the pipe 42, the elevating shaft 48 holding the chip 9 in the collet 49 rotates about the pipe 42 integrally with the holder 41, and its pin 54 is the engaging element 6
7 stops at the position where it engages. The right elevating shaft 48 in FIG. 2 and FIG. 4 show the state at this time. In this state, as shown in FIG.
Reference numeral 5 is apart from the upper end of the outer cylinder 51 (see the gap G1), and the enlarged portion 53 of the elevating shaft 48 is grounded to the upper end of the outer cylinder 51. At this time, the upper end of the outer cylinder 51 hits the lower surface of the upper flange 41a, thereby defining a rising limit.

Next, as shown in FIG. 5, the pressing rod 19 descends and pushes down the rod 62. Then, the piston unit 65 descends, and its lower surface hits the upper end of the outer cylinder 51,
The outer cylinder 51 is pushed down, and the outer cylinder 51 and the elevating shaft 48 descend. Next, when the chip 9 lands on the upper surface of the substrate 5,
When the piston unit 65 further descends, the enlarged portion 53 separates from the upper end of the outer cylinder 51 (see the gap G2), the lowering operation of the elevating shaft 48 is free from the outer cylinder 51, and the groove upper surface of the engaging element 67 Thereafter, only the load applied from the piston unit 65 is transmitted to the elevating shaft 48 via the engaging element 67 and the pin 54, and the chip 9 sucked by the collet 49 is pressed against the substrate 5. Can be

That is, in this device, the chip 9 can be pressed against the substrate 5 only by the load applied from the piston unit 65. Therefore, by controlling the electropneumatic regulator 68 by the control device 69, the chip size can be adjusted. An optimum load can be applied to the chip 9 and pressed against the substrate 5. Then, when the operation of pressing the chip 9 against the substrate 5 is completed, the vacuum suction state of the chip 9 by the collet 49 is released, and if the pressing rod 19 is raised, the state returns to the initial state shown in FIG.

[0024]

According to the present invention having the above-described structure, the pressing force can be changed by the pressing force changing means in accordance with the chip size of the chip on which the collet has been vacuum-adsorbed. It 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 sectional view of a transfer head of the electronic component mounting apparatus according to one embodiment of the present invention;

FIG. 3 is a perspective view of the vicinity of an upper end of a lifting shaft of a transfer head of the electronic component mounting apparatus according to the embodiment of the present invention;

FIG. 4 is a partial sectional view of a transfer head of the electronic component mounting apparatus according to one embodiment of the present invention;

FIG. 5 is a partial cross-sectional view of a transfer head of the electronic component mounting apparatus according to one embodiment of the present invention.

FIG. 6 is a cross-sectional view of a collet elevating mechanism provided in a transfer head of a conventional electronic component mounting apparatus.

[Explanation of symbols]

 2 Wafer 5 Substrate 9 Chip 40 Transfer head 41 Holder 43 Motor 48 Elevating shaft 49 Collet 52 Spring 60 Pressing means 65 Piston unit 67 Electropneumatic regulator 69 Controller

Claims (1)

(57) [Claims] An electronic component mounting apparatus for picking up a chip by a transfer head and transferring and mounting the chip on a substrate positioned at a positioning portion, wherein the transfer head has a collet at a lower end portion for vacuum-sucking the chip. Shaft and
A holder for holding a plurality of the elevating shafts so as to be able to move up and down, a spring for resiliently lifting the elevating shafts,
Pressing means for pressing down the elevating shaft with a predetermined pressing force against the spring force of the spring; and any one of the plurality of elevating shafts by moving the holder relative to the pressing means. or one collet selecting means for positioning the elevating operation position by said pressing means, and a pressing force changing means for changing the pressing force of the pressing means in response to the selection operation of the collet selection means, variable pressing force
A piston whose pushing means is pushed down by the pushing means
Unit and the electro-pneumatic rail connected to this piston unit.
Regulator and plunger of this piston unit.
An engaging element engaged with the lifting shaft and
A control device for controlling the empty regulator.
After the chip descends and the chip lands on the board,
Load applied from the piston unit via a child
To the elevating shaft and press the chip against the substrate
Electronic component mounting apparatus is characterized in that the so that.