JP2584338B2 - Component mounting device - Google Patents

Description

The present invention relates to an apparatus for mounting a surface mount component on a circuit board.

(B) Conventional technology In order to mount a surface mount component on a circuit board, a vacuum suction type pick and place device is usually used. There is also a type in which a component positioning jaw is provided on a head portion for performing a pick and place operation, and the component is centered around a nozzle center. One example is described in JP-A-62-111496.

(C) Problems to be Solved by the Invention The present invention aims to enable fine adjustment of a component positioning jaw in the component mounting apparatus as described above.

(D) Means for Solving the Problems In the present invention, the component mounting device is provided with the following configuration.

(A) a spindle which is vertically arranged and has a vacuum suction path inside; (b) a nozzle which is mounted on a lower end of the spindle and which communicates with the vacuum suction path at the time of mounting; Power means for vertically moving the spindle (d) swingably supported by a structure that supports the spindle so as to be able to move up and down, and centering the parts adsorbed on the nozzles by a movement of closing their tips. (E) a power means for causing the component positioning jaw to open and close; (f) a support shaft for at least one of the component positioning jaw pair; Eccentric shaft for free end fine movement.

(E) Operation When the eccentric shaft is rotated, the fulcrum of the component positioning jaw moves, and accordingly, the free end of the component positioning jaw also displaces. This enables fine adjustment.

(F) Example An example will be described below with reference to the drawings.

—Overall Configuration— FIG. 1 shows a schematic configuration of the component mounting apparatus 10. The component mounting apparatus 10 has a box-shaped base 11, on which an XY stage is mounted.
Components such as 20, a head unit 30, a nozzle replacement unit 140, a conveyor unit 150, a substrate support unit 160, and a first component supply unit 170 are arranged. Reference numeral 180 denotes a second component supply unit placed beside the base 11. A first imaging unit 191 and a second imaging unit 192 are attached to the head unit, and a third imaging unit is provided beside the conveyor unit 150.
An imaging unit 193 is provided. Next, each component will be described in detail.

-XY stage- The XY stage 20 is a column that stands from the four corners of the base 11.
By 21, it is supported high above the base 11. 22 is XY
A bridge part that forms part of the stage 20 connects the upper ends of the two columns 21 in the direction of the short side of the base 11. twenty three
Is a linear slide guide which is also a part of the XY stage 20 and connects the upper ends of the two columns 21 in the long side direction of the base 11. The two linear slide guides 23 support the X motion block 24. The X motion block 24 is moved along the linear slide guide 23 by a ball screw 25 bridged between the two bridge portions 22 and a motor 26 for rotating the ball screw 25. The X-movement block 24 incorporates a Y-movement unit that supports the head unit 30 and moves the head unit 30 in a direction perpendicular to the linear slide guide 23. The mechanism of the movement of the Y motion unit is also the same as that of the X motion block 24, using a ball screw and a motor.

—Head Unit— The head unit 30 is supported by the XY stage 20 in a suspended state, and includes a mechanism shown in FIG. That is, in FIG. 3, reference numeral 31 denotes a vertically arranged spindle, which is supported at the center of a hollow shaft 32 by a slide bearing 3 so as to be slidable in the axial direction, that is, vertically movable. The hollow shaft 32 is rotatably supported in a frame structure 34 via a bearing 35. That is, the spindle 31 can move up and down and rotate, and pick and place a part by moving up and down, and orient the part in a predetermined direction by turning. The mechanism of vertical movement and rotation will be described later.

The spindle 31 is formed by joining two upper and lower pipes, and a central portion is a vacuum suction path 36. At the upper end of the spindle 31, a flange 37 and a joint holder 38 are provided.
It is fixed in the form stacked in this order. The joint holder is equipped with a rotary joint 39, from which a vacuum hose 40 is installed horizontally.
Extends. In order to keep the direction of the vacuum hose 40 constant, in other words, to prevent the vacuum hose 40 from rotating even when the spindle 31 rotates, the following measures have been taken. That is, the ring 41 is arranged outside the joint holder 38. A bearing 42 is interposed between the ring 41 and the joint holder 38,
The ring 41 is rotatable with respect to the joint holder 38. ring
A stay 43 shown in FIG. 5 is fixed to the upper surface of 41, and a joint 39 penetrates the stay 43, whereby the ring 41 and the joint 39 are connected so as not to rotate with each other. Reference numeral 44 denotes a plate-shaped bracket fixed to the side surface of the ring 41. A vertical groove 45 is formed from the lower edge, and rollers 46 rotating around a horizontal axis are attached to both sides of the groove 45. The roller 46 stops the rotation of the ring 41 and the rotation of the joint 39 by sandwiching a lever (described later) for lifting the flange 37. As shown in FIG. 4, a tension coil spring 47 is stretched between the ring 41 and the frame structure 34, and applies a downward force to the spindle 31.

The lower end of the spindle 31 is tapered and the nozzle 50 is detachably fitted thereto. At the same time, the vacuum suction path 36 communicates with the nozzle 50. Reference numeral 51 denotes a pair of levers pivotally supported on the outer surface of the spindle 31. The pair of levers 52 engage the grooves 53 on the outer surface of the nozzle 50 (FIG. 13) to prevent the nozzle 50 from falling off. . A tension coil spring 54 is stretched between the pair of levers 51.
A force is generated that causes the roller 52 to elastically contact the nozzle 50. The nozzle 50 can be replaced with another type prepared in the nozzle replacement unit 140.

At the lower end of the hollow shaft 32, a square mount base 60 as shown in FIG. 8 is formed, in which two pairs of component positioning jaws 61a, 61b, 62a, 62b are respectively formed in a vertical plane. It is pivoted so that it can swing. The arrangement state of the component positioning jaws 61a, 61b, 62a, 62b in the space is as shown in FIGS. That is, the pair of component positioning jaws 61a and 61b and the pair of 62a and 62b
As a result, the jaw tips 63 of the component positioning jaws 61a and 61b and the jaw tips 64 of the component positioning jaws 62a and 62b sandwich the component from directions orthogonal to each other.

The opening / closing mechanism of the component positioning jaws 61a, 61b, 62a, 62b is as follows. Note that the component positioning jaw
Since the opening and closing mechanism is the same for both 61a, 61b and 62a, 62b,
Here, only the component positioning jaws 61a and 61b will be described. As can be seen in FIG. 10, the component positioning jaws 61
A tension coil spring 65 is stretched at a position above the swing center of a and 61b, so that the jaw tips 63 and 63 are urged away from each other. Parts positioning jaw 61
Protruding pieces 66a, 66b are formed on the opposing side surfaces of a, 61b, also above the swing center. The protruding pieces 66a and 66b overlap in the depth direction of the paper in FIG. 10, and the roller 68 of the slider 67 scoops up the overlapping portion. When the slider 67 slides upward along the outer surface of the hollow shaft 32, the jaw tips 63, 63 approach as shown in FIG. 11, and conversely, when the slider 67 descends, the jaw tips 63, 63
Will be away from each other. The slider 67 is slid by a flange cylinder 69 fitted to the outside of the hollow shaft 32. The flange cylinder 69 and the slider 67 are connected by a tension coil spring 70, and when the flange cylinder 69 is pulled up, the slider 67 also rises. As shown in FIG. 13, the slider 67 is a flanged cylinder.
It has an upper extension 71 extending to the outer surface of 69, and two rollers 73 are pivotally supported vertically spaced in a vertically elongated hole 72 formed therein. Reference numeral 74 denotes a cover fixed to the flange cylinder 69 by screws 75, which fits into the recess of the upper extension 71 and serves to maintain the slider 67 on the outer surface of the hollow shaft 32. The cover 71 has a leg 76 through which a screw 75 passes, which penetrates the slot 72. The upper end of the cover 74 is engaged with the flange cylinder 69, thereby preventing the cover 74 from rotating around the screw 75. Also the protrusion on the back of the cover 74
77 sandwiches the roller 73 between itself and the flange cylinder 69 to ensure smooth movement of the slider 67. Reference numeral 78 shown in FIGS. 4 and 5 is a holder for retaining the component positioning jaws 61a, 61b, 62a, 62b.

The component positioning jaws 61a, 61b, 62a, 62b are provided with an adjusting mechanism for finely adjusting the position of the swing end.
14 and 15, taking the component positioning jaws 61a and 61b as an example.
A description will be given based on the drawings. The eccentric shaft 80 constitutes the support shaft of the component positioning jaws 61a and 61b. The eccentric shaft 80 has a shaft center portion 81 that fits into the mount base 60, and a first eccentric portion 82 and a second eccentric portion 83 located outside the mount base 60. A bearing 84 is fitted outside the first eccentric portion 82,
The component positioning jaws 61a and 61b are supported via the bearing 84. The second eccentric part 83 is larger in diameter than the first eccentric part 82,
It has a flat portion 85 on both sides and can be turned around with a spanner. The flat portion 85 projects outside from a window 86 opened in the holder 78. The phases of the eccentricity of the first eccentric portion 82 and the second eccentric portion 83 are the same, and the direction of the first eccentric portion 82 can be seen by looking at the second eccentric portion 83 from the outside. The eccentric shaft 80 is fixed to the mount base 60 by a bolt 87 penetrating the eccentric portion 81, and can be rotated by loosening the bolt 87. The effect of the rotation of the eccentric shaft 80 will be described with reference to FIG. Although the eccentric shaft 80 of the component positioning jaw 61a is drawn with the eccentric portion facing the horizontal direction, the eccentric shaft 80 arranged in this shape rotates the component positioning jaw 61a
a is mainly displaced in the vertical direction. Although the eccentric shaft 80 of the component positioning jaw 61b is drawn with the eccentric part oriented vertically, the eccentric shaft 80 arranged in this shape causes the component positioning jaw 61b to mainly displace in the lateral direction due to its rotation. Cause. In this way, even if the adjusting mechanism is not provided on both of the pair of component positioning jaws, the practical purpose is achieved only by providing the adjusting mechanism on one of the pair.

The vertical movement of the spindle 31 and the flange cylinder 69 is
16 is a cam device 90 shown in FIGS. 16 to 23. FIG. Reference numeral 91 denotes a frame of a cam device 90 on which a cam shaft 92 is horizontally supported. The cam shaft 92 is connected to a pulse motor 93 fixed to a frame 91, and has two cams 94 and 95 fixed outside. Reference numeral 96 denotes a lever located above the cam shaft 92 and supported by a support shaft 97 so as to be able to swing in a vertical plane, and has a cam follower roller 98 in contact with the cam 94 at an intermediate portion.
At the free end, a roller that supports the flange 37 of the spindle 31
99 is installed. The lever 96 is 2 when viewed from above.
The plate is placed in parallel, and one end of the plate enters between the rollers 46 of the bracket 44 and the ring 41
The rotation of is stopped. Below the cam shaft 92, upper and lower two-stage levers 100 and 101 are arranged. The lever 100 is supported by a support shaft 102 so that it can swing in a vertical plane.
And a cam follower roller 103 that comes into contact with. Lever 101
Is supported by a pivot 104 so that it can swing in a vertical plane,
The free end has a roller 105 that engages with the flange cylinder 69.
A free end of the lever 100 and an intermediate portion of the lever 101 are connected by a turn-buckle type link 106. 107 is lever 10
This is a tension coil spring that connects to 1 and pulls it up.
Is generated.

In FIG. 20, reference numeral 110 denotes an AC servomotor fixed to the frame 91, which is a timing pulley 111 fixed to the hollow shaft 32.
To rotate through the timing belt 112. The rotation of the hollow shaft 32 is transmitted to the spindle 31 by the mechanism shown in FIGS. That is, a transmission piece 113 is fixed to the spindle 31, and the transmission piece 113 extends outward through a slit 114 formed at a corner of the mount base 60. The transmission piece 113 that has come out of the hollow shaft 32 is sandwiched between a pair of rollers 115 pivotally supported by the mount base 60. In order to maintain the rotation transmission from the hollow shaft 32 regardless of whether the spindle 31 is up or down, the portion of the transmission piece 113 located outside the mount base 60 has a sufficient length in the up and down direction. In order to eliminate backlash in the rotating direction of the hollow shaft 32 and the spindle 31, an adjusting mechanism using an eccentric shaft is used for one roller 115, as in the case of the positioning jaw, so that the roller 115 can be slightly moved in the lateral direction. I have.

Reference numeral 120 in FIG. 23 is a brake mechanism provided for the camshaft 92. The brake mechanism 120 includes a brake wheel 121 fixed to the cam shaft 92, a brake shoe 122 swingably mounted on the frame 91, a spring 123 for bringing the brake shoe 122 into contact with the brake wheel 121, and an attachment of the spring 123. The main component is a solenoid 124 that pulls the brake shoe 122 in a direction opposite to the force. Brake wheel 121
The brake shoe 122 is composed of a pinion and a rack. A current flows through the solenoid 124 at the same time that the component mounting device 10 is energized, and the brake shoe 122 is separated from the brake wheel 121 as shown in FIG. When the power supply to the component mounting device 10 is cut off, the brake shoe 122 contacts the brake wheel 121 as shown in FIG.
Stop the rotation of.

At the lower end of the frame structure 34, a flat rectangular frame 13 is provided.
Fix 0. One illuminating body 131 is attached to each of two opposing sides of the frame body 130 so as to illuminate the center direction of the frame body 130, respectively. The lighting body 131 is formed of a cold cathode ray tube.

-Nozzle replacement unit-The nozzle replacement unit 140 always holds multiple types of nozzles,
Although the nozzle at the lower end of the spindle 31 is replaced according to the type of the component, its mechanism is not the gist of the present invention, and therefore the description is omitted, and the above-mentioned Japanese Patent Application Laid-Open Nos.
It is only stated that a mechanism as described in Japanese Patent Application Laid-Open No. 3-16700 and Japanese Patent Application Laid-Open No. 1-121138 is adopted. This nozzle is roughly divided into a normal type nozzle 50 as shown in FIGS. 10 to 13, and an image recognition nozzle 14 shown in FIG.
There are 1 and 2 types. The image recognition nozzle 141 is for handling a component whose position is determined by image recognition, such as a flat pack IC, and has a horizontal background plate 142 above the component suction unit. Background plate 142
Is made of a transparent plastic having a rectangular shape in a plan view, provided with a special reflective layer 143 on the upper surface, and scatters and reflects light incident from an edge portion at the interface with the reflective layer 143 and emits the light from the lower surface.

-Conveyor part- The conveyor part 150 has a fixed rail part 151 and a movable rail part 152.
Having. “Movable” of the movable rail section 152 means that the distance between the movable rail section 152 and the fixed rail section 151 can be adjusted. Both the fixed rail portion 151 and the movable rail portion 152 have a belt 153 on the inner surface, and convey the circuit board 1 by this. Positioning means for stopping the circuit board 1 at a fixed position is provided in the middle of the conveyor section 150, but this is not shown.

—Substrate Support Unit— The substrate support unit 160 supports the circuit board 1 positioned on the conveyor unit 150 from below, and prevents the circuit board 1 from bending even when the spindle 31 applies pressure. JP
A mechanism similar to that described in JP-A-59-29492 can be employed.

-First Component Supply Unit- The first component supply unit 170 includes a plurality of component supply modules 171 arranged in a line. The individual component supply modules 171 are for supplying the normal surface mount components 2 (chip capacitors, chip resistors, etc.) shown in FIG. 10 to FIG.
And supply them one by one. Component supply module
As 171, those described in JP-B-62-52960 can be employed.

-Second component supply unit- The second component supply unit 180 is mainly composed of a cabinet 181 installed beside the base 11, but also includes a positioning unit 182 installed on the base 11 along with the nozzle replacement unit 140. It is a part of. The cabinet 181 is equipped with a rectangular coordinate robot 183, which is a cabinet 181.
A multi-leaded component 3 such as a flat pack IC (FIG. 19) is picked up from a tray (not shown) in the
Put on 182. The positioning portion 182 pushes the multi-lead component 3 so that the plurality of jaws do not bend the lead, thereby roughly positioning the lead. Then, the head unit 30 approaches the positioning unit 182 and picks up the multi-lead component 3.

-Imaging Unit- The first imaging unit 191, the second imaging unit 192, and the third imaging unit 193 are each mainly composed of an industrial television camera. The first imaging unit 191 and the second imaging unit 192 are attached to the head unit 30. The first imaging unit 191 is provided with a fiducial mark (fid) printed on the circuit board 1.
The second imaging unit 192 is also used to recognize a foot pattern (land pattern for soldering the leads of the multi-lead component 3) printed on the circuit board 1 as well. The third imaging unit 193 is installed beside the positioning unit 182 so as to look upward, and is used for recognition of the multi-lead component 3 sucked by the image recognition nozzle 141.

—Control Unit— The automatic control system of the component mounting device 10 is as shown in FIG. Reference numeral 200 denotes a main body control unit, and the central processing unit is a central processing unit 201, which includes a memory 202, a CRT 203,
A keyboard 204 is included. The central processing unit 201 controls the illumination controller 206, the XY stage controller 207, the head controller 208, the nozzle replacement controller 209, the conveyor controller 210, the board support controller 211, and the component supply controller 212 via the bus line 205. I do. The illumination controller 206 controls the illumination unit 213, and the illumination unit 213 includes the first imaging unit 191 and the second imaging unit 19
Second, the collective designation of the illumination units combined with the third imaging unit 193, and the illumination body 131 is also included therein.

A recognition unit 220 is provided separately from the main body control unit 200. This is the central processing unit 221 and the attached memory 222, CRT 223,
A / D converter 225 connected to bus 221 via bus line 224,
An image processing unit 226 is provided. A / D converter 225 is the first
It is connected to the imaging unit 191, the second imaging unit 192, and the third imaging unit 193. The central processing unit 221 is provided in the central processing unit 20 of the main body control unit 200.
1 and a communication line 230. A communication line 231 with an external device is also connected to the central processing unit 201.

—Operation— Before starting the component mounting apparatus 10, the spindle 31 is in the raised position, and the brake shoe 122 is in contact with the brake wheel 121. When power is supplied for operation, the solenoid 124 operates to separate the brake shoe 122 from the brake wheel 121, and the camshaft 92 becomes rotatable. In the following, we will start picking and placing parts, but here, first,
The description will proceed assuming that the normal nozzle 50 is mounted on the spindle 31. At the same time as the operation starts, the XY stage 20 moves the head unit 30 onto an arbitrary component supply module 171 of the first component supply unit 170. Here, when the pulse motor 93 rotates the cam shaft 92 clockwise in the figure from the angular position in FIG. 18 to the angular position in FIG. 16, the free end of the lever 96 is lowered, and the spindle 31 is lowered, The nozzle 50 sucks the component 2. The free ends of levers 100 and 101 also go down,
As a result of the lowering of the flange cylinder 69, the component positioning jaws 61
a, 61b, 62a, 62b open outward. After picking up part 2,
When the cam shaft 92 is rotated counterclockwise, the spindle 31 moves up with the part 2. Due to the relationship between the cam curves of the cams 94 and 95, until the nozzle 50 reaches the height shown in FIG.
69 has no movement. When the nozzle 50 reaches the height of FIG. 17, the spindle 31 stops rising despite the rotation of the cam shaft 92, and the flange cylinder 69 starts to rise instead. Then, the component positioning jaws 61a, 61b, 62a, 62b are closed, and the component 2 is brought to the center of the nozzle 50. When the part 2 is sandwiched, the part positioning jaw cannot be closed any more, but the excess stroke of the flange cylinder 69 thereafter is absorbed by the extension of the extension coil spring 70 (FIG. 12). Following or simultaneously with the centering of part 2,
The AC servomotor 110 rotates the hollow shaft 32 to turn the component 2 in a predetermined direction. While these actions take place, XY
The stage 20 moves the head unit 30 to a predetermined coordinate position on the circuit board 1. The circuit board 1 is applied with an adhesive (by screen printing or a dispenser) at a component mounting position in a previous process, and is positioned on the conveyor unit 150.
Further, the displacement of the circuit pattern of the circuit board 1 is determined by the first imaging unit.
191 is checked by recognizing the fiducial mark, X
It is corrected in the movement of the Y stage 20. Spindle 3
When 1 is lowered and the component 2 is moved to the circuit board 1, one cycle of the pick and place operation is completed. If the positioning accuracy of the component positioning jaws 61a, 61b, 62a, 62b decreases due to wear of the jaw tips 63, 64, etc., the eccentric shaft
Rotate 80 to restore accuracy.

When mounting the multi-lead component 3 using the image recognition nozzle 141, the raising of the spindle 31 is stopped short of the upper limit of the stroke. That is, in the state of FIG. 19, the image recognition nozzle 141 has the component positioning jaws 61a, 61b, 62a,
It is outside the operating area of 62b. At this time, the background plate 142 is
When the illuminator 131 is turned on at the same height as 1, light from the illuminator 131 enters from the edge of the background plate 142 and is turned downward by the reflective layer 143 to raise the silhouette of the multi-lead component 3. The head unit 30 in this state is connected to the third imaging unit 19
3 and check the misalignment of the multi-lead component 3 with respect to the image recognition nozzle 141. After that, the head unit 30 is moved onto the rotating substrate 1 and superimposed on the foot pattern checked by the second imaging unit 192 with the deviation corrected.

Even if a power failure occurs during the pick-and-place operation, the rotation of the cam shaft 92 is stopped by the brake mechanism 120, so that the spindle 31 does not fall, and the circuit board 1 is damaged or the nozzle is damaged. No.

(G) Effects of the Invention According to the present invention, the component positioning jaw is finely moved only by giving an angle change to the eccentric shaft, and the operation is very simple.

[Brief description of the drawings]

FIG. 1 shows an embodiment of the present invention. FIG. 1 is a partially cutaway perspective view of a component mounting apparatus, FIG. 2 is a block diagram showing a control system, FIG. FIG. 3 is a side view of the portion of FIG. 3, and FIG. 5 is a side view of the portion of FIG. 3 as viewed from a direction perpendicular to FIG. FIG. 6 is a partial sectional view of a part of the head section taken along a plane different from FIG. 3, and FIG.
It is a front view of the part of a figure. FIG. 8 is a bottom view of the head portion, in which the component positioning jaws are cut away and partially cut away, and FIG. 9 is a bottom view of only the component positioning jaws. 10 to 12 are partial front views showing the opening / closing mechanism of the component positioning jaw and its movement, and FIG. 13 is a partial sectional view presented for the same purpose. 14 and 15 are a partial front view and a partial cross-sectional view illustrating a fine adjustment mechanism of the component positioning jaw. 16 to 19 are explanatory views of the function of the cam, and FIGS. 20 to 22 are horizontal sectional views showing the structure of the cam device and the lever related thereto. FIG. 23 is a sectional view showing a brake mechanism, and FIGS. 24 and 25 are partial front views showing the structure and operation of the brake mechanism. 1 ... Component mounting device, 31 ... Spindle, 36 ... Vacuum suction path, 50 ... Nozzle, 141 ... Nozzle for image recognition, 9
0, 93 ... Cam device and pulse motor constituting power means, 61a, 61b, 62a, 62b ... Part positioning jaws, 80 ...
... Eccentric shaft.

Claims (1)

(57) [Claims] 1. A component mounting apparatus having the following configuration. (A) a spindle which is vertically arranged and has a vacuum suction path inside; (b) a nozzle which is mounted on a lower end of the spindle and which communicates with the vacuum suction path at the time of mounting; Power means for vertically moving the spindle (d) swingably supported by a structure that supports the spindle so as to be able to move up and down, and centering the parts adsorbed on the nozzles by a movement of closing their tips. (E) a power means for causing the component positioning jaw to open and close; (f) a support shaft for at least one of the component positioning jaw pair; Eccentric shaft for free end fine movement.