JPH04322924A - parts mounting device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a component mounting device used for mounting electronic components such as semiconductor chips to a circuit board in the manufacturing process of electronic circuit boards.

0002

[Background Art] Generally, in the manufacturing process of electronic circuit boards, as a device for positioning and mounting electronic components such as semiconductor chips on the board, a nozzle that vacuum-chucks the components and a nozzle head that is rotatable and movable up and down are used. 2. Description of the Related Art A component mounting device is known that positions and mounts components by moving the nozzle head up and down and rotating on its own axis, and moving the nozzle head back and forth and left and right.

[0003] Conventionally, in this type of device,
As a countermeasure against misalignment of electronic components with respect to the nozzle during suction, the following configuration was adopted. That is, as seen in Japanese Patent Publication No. 62-10793, for example,
Two pairs of position regulating claws provided on the nozzle head center the electronic components attracted to the nozzle (positioning them relative to the nozzle) to prevent the electronic components from being attracted to the nozzle if they are misaligned. . Alternatively, the amount of adsorption deviation with respect to the nozzle is determined by image processing by capturing the adsorbed electronic component from below with an ITV camera, and the amount of movement of the nozzle head and the rotation angle of the nozzle relative to the mounting position of the component are corrected according to this amount of deviation. I was dealing with it.

0004

However, the position correction using the position regulating claw has the following problems. (1) Shocking force is applied to electronic components, reducing the reliability of the components. (2) Correction accuracy is determined by the machining accuracy and assembly accuracy of the claws. (3) If used for a long period of time, the correction accuracy will decrease due to bearing wear, etc.

On the other hand, position correction using an ITV camera has the following problems. (4) Image processing takes time and loading speed is slower than the claw type. (5) An expensive ITV camera image processing device is required and the cost is higher than that of the claw type.

The present invention has been developed in view of the above-mentioned conventional problems, and is capable of accurately and reliably correcting misalignment of components without damaging the components, and moreover, is fast in mounting speed and inexpensive. The purpose is to provide a parts mounting device.

[0007]

[Means for Solving the Problems] The component mounting device of the present invention has a nozzle head that rotatably and vertically movably supports a nozzle for removably holding a component with a suction section vertically below the nozzle. Along with moving it up and down and rotating it,
By moving the nozzle head in the horizontal direction,
In a component mounting device for positioning and mounting components, a light projecting unit that emits a horizontal parallel light beam to this region on one side of the region in which the component held by the nozzle moves up and down;
The nozzle head is characterized in that the nozzle head is provided with a light receiving part that receives the parallel light flux on the opposite side of the area with respect to the light projecting part and converts the brightness and darkness of the light into an electrical signal in accordance with the light receiving position.

[0008]

[Operation] With the above configuration, the parallel light beam is irradiated from the side surface of an electronic component such as a semiconductor chip, so that the portion of the external shape of the electronic component projected in the horizontal direction appears dark on the light receiving device. be able to. In other words, if the part is placed in the area where the light emitting part emits a parallel beam by moving the nozzle that has attracted the part horizontally up and down, this part will block a part of the parallel beam, and the outer shape of the part will be changed to the side. The projected area is detected as dark on the light receiving section.

In this state, while horizontally rotating the component by rotating the nozzle, the positions of both ends of the dark range in the direction orthogonal to the parallel light beam are
By sequentially storing the rotation angle of the part (nozzle) at that time and collecting this data at appropriate intervals until the part has rotated at least 180 degrees, this data can be used to determine the amount of positional deviation or rotation of the part with respect to the nozzle center. The amount of deviation (the inclination of the component with respect to the reference axis) can be determined through calculation processing.

That is, a component such as a semiconductor chip has a rectangular planar shape, and if it is horizontally rotated by 180 degrees or more, each side surface (long side and short side) becomes parallel to the above at any rotation angle. There is at least one time in each case when the parallel light beam becomes parallel to the parallel light beam (that is, when the vertical or horizontal direction of the component becomes parallel to the parallel light beam). Then, if a graph is drawn in which the horizontal axis is the rotation amount of the component and the vertical axis is the distance from the reference position to the edge of the dark range in the direction orthogonal to the parallel light beam, the side surface of the electronic component is the parallel light beam. A point on this graph at an amount of rotation that is parallel to , becomes an inflection point where the slope of the line on the graph is discontinuous.

[0011] For this reason, the data is processed and determined by, for example, a controller equipped with a microcomputer, and the position of both ends of the range in which the light receiving section becomes dark when the part becomes parallel to the parallel light beam and the rotation thereof are determined. It is possible to determine the amount of rotation, and calculate backward from this amount of rotation to determine the amount of rotational deviation between suction and rotation of the electronic component, and also to determine the positional deviation of the center of the electronic component in both directions from the positions of both ends. This is because, for example, if the direction of the parallel light beam is made to match the reference axis (direction of movement of the nozzle head), the amount of rotation when the component becomes parallel to the parallel light beam is the inclination of the component when it is picked up with respect to the reference axis. This is because there is nothing else. Further, since the position of the nozzle center in the direction orthogonal to the parallel light beam is known in advance, for example, when the longitudinal direction of the component becomes parallel to the parallel light beam, the center position of the dark range and the nozzle center position This is because the distance between the two is nothing but the amount of deviation in the suction position of the component in the vertical direction.

[0012] Therefore, if the amount of rotation of the nozzle or the amount of movement of the nozzle head when mounting (attaching) parts is corrected based on the obtained positional deviation data,
Even if the component is misaligned or tilted relative to the nozzle during suction, the component can be positioned with high precision and mounted on an electronic circuit board or the like.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. 1 to 8. FIG. 1 is a perspective view of a component mounting device. In the figure, numeral 1 is a base, numeral 2 is a controller that controls the operation of each part, and numeral 3 is a vertical axis (
The nozzle head is rotated around the θ axis) and moved in the vertical direction (Z direction).
It shows an XY robot that moves in the Y direction (back and forth and left and right directions). Further, reference numeral 4a is an X-axis moving mechanism of the XY robot 4, reference numeral 5 is a Y-axis motor of the XY robot 4 for moving the nozzle head 3 in the Y direction together with the X-axis moving mechanism 4, and reference numeral 6 is a Y-axis motor of the XY robot 4 for moving the nozzle head 3 in the The X-axis motor of the XY robot is used to move the robot in the directions; 7 is the θ-axis motor that rotates the parts attracted to the nozzle head 3; 8 is the operation panel; 9 is used to supply parts such as semiconductor chips. A tape feeder is shown.

FIG. 2 is a longitudinal sectional view of the nozzle head 3. In FIG. 2, the reference numeral 10 denotes a hollow nozzle shaft disposed in the vertical direction (Z-axis direction) within a prismatic body 3a constituting the outer frame of the nozzle head 3. is provided, and the parts are attracted to the tip of this nozzle 11. Reference numeral 12 indicates a nozzle guide, which is a guide for moving the nozzle shaft 10 in the vertical direction without rotating it. That is, the nozzle guide 12 is mounted within the body 3a by a bearing 17 and is rotatable about the same axis as the nozzle shaft 10. Note that the nozzle shaft 10 is slidably inserted on the axis within the nozzle guide 12;
Rotation with respect to the nozzle guide 12 is prevented by a rolling element 18 that is attached to the nozzle guide 12 and engages with a groove 10a on the outer periphery of the nozzle shaft 10.

Further, reference numeral 13 indicates a pulley, which is fixed to the upper end of the nozzle guide 12 and is connected to the θ-axis motor 7.
The timing belt is used to transmit the rotation of the nozzle guide 12 to the nozzle guide 12. Reference numeral 14 indicates a nozzle upper and lower cylinder, in which a piston 14a thereof is fitted into a working chamber 3b formed in a body 3a, and the tip of a rod 14b extending from the upper end of this piston 14a is connected to a nozzle shaft via a connecting plate 19. It is connected to the upper end of 10. That is, the nozzle shaft 10 is configured to move up and down (in the Z-axis direction) while sliding with respect to the nozzle guide 12 by the operation of the cylinder 14. Note that the nozzle upper and lower cylinders 14 can be operated, for example, by air pressure. Further, in this case, when the nozzle shaft 10 is raised by the cylinder 14, the component 16 attracted to the nozzle 11 is located in a region irradiated with a parallel light beam 15c, which will be described later.

The upper end of the nozzle shaft 10 is configured to be alternatively connected to an intake device such as a vacuum pump or a compressed air source, and by this switching, if the inside of the nozzle shaft 10 is evacuated, as shown in FIG. Part 1 as shown in 2
6 is attracted, and conversely, when compressed air is supplied, the component 16 is separated from the nozzle 11.

In FIG. 2, the reference numeral 15 indicates a length measuring unit provided on the lower surface of the body 3a. This length measuring unit 15 consists of a light projecting section 15a that emits a parallel light beam 15c, and a light receiving section 15b that receives this parallel light beam and converts it into an electrical signal in accordance with the light receiving position. The nozzles 11 are arranged to face each other across the vertical region.

Note that the parallel light beam 15 emitted by the light projecting section 15a
As shown in FIG. 3, c is parallel to a plane (that is, a horizontal plane) orthogonal to the central axis (Z-axis) of the nozzle 11, and its direction is in the Y-axis direction in this case. The width of the parallel light beam 15c in the horizontal direction is set to be larger than at least the outer shape of the component 16. In addition, the parallel light beam 15c
The thickness in the vertical direction (Z-axis direction) is set to be thinner than the thickness of the component 16, and when the nozzle 11 that has absorbed the component 16 is raised to the upper end, a part of the parallel light beam 15c is blocked by the component 16. It has become.

Then, as shown in FIG. 3, when the nozzle 11 that has picked up the component 16 is raised to the upper end, the distances S1 and S2 at which the parallel light beam 15c emitted from the light emitting section 15a is blocked by the component 16 are determined by the distances S1 and S2 from the light receiving section 15b. Based on the output signal of the length measuring unit controller 2 in the controller 2
It is determined by 0. Here, the distance S
As shown in FIG. 4, 1 and S2 are values representing the positions of the horizontal ends of the dark area in the light receiving section 15b when the parallel light beam 15c is blocked, and in this case, in FIG. The distance from the lower end to the lower end of the dark region is S1, and similarly the distance from the lower end of the parallel light beam 15c to the upper end of the dark region is S2. Note that the symbol S0 in FIG. 4 indicates the parallel light beam 1 in this figure.
5c to the axis of the nozzle 11, and this value is a constant value that is determined in advance based on the relative positional relationship between the length measuring unit 15 and the nozzle 11, regardless of the dimensions of the component 16 or the deviation of the suction position. .

FIG. 5 shows the configuration of the controller 2. The controller 2 includes an operation control section 17 that is connected to the operation panel 8 and controls the operation of the entire device, and an XY robot control section 1.
8, a nozzle head control section 19, a length measurement unit controller 20, and a memory 21.

The XY robot control section 18 has a function of controlling the XY robot 4 in response to commands from the motion control section 17 and moving the position of the nozzle 11 (nozzle head 3) to an arbitrary XY coordinate. The nozzle head control unit 19 controls θ
It controls the operation of the shaft motor 7, the nozzle upper and lower cylinders 14, or the switching of the connection of the nozzle shaft 10 to the compressed air source, sets the vertical position and rotation angle (θ) of the nozzle 11 as instructed, and also controls the nozzle Parts 16 to 11
It controls the adsorption or desorption of. memory 21
is the data for moving the nozzle 11 to the mounting position of the component 16 or its supply position, that is, the nozzle 11
It stores the XY coordinates of the position to be moved and the rotation angle of the nozzle 11, or the output from the length measuring unit controller 20.

Next, the operation of the component mounting apparatus constructed as described above will be explained with reference to FIGS. 6 to 8. FIG. 6 is a PAD diagram showing the operation of the controller 2 for detecting the positional deviation of the sucked electronic component with respect to the nozzle 11 and correcting the amount of deviation. This will be explained step by step below.

[Step S1] The coordinates (X1, Y1) of the position to which the nozzle 11 should move to receive the component 16 (in this case, for example, the position of the tape feeder 9) are read from the memory 21.

[Step S2] The coordinates (X1, Y1) read in step S1 are sent to the XY robot control section 18, and the nozzle 11 is moved to the position of the coordinates (X1, Y1).

[Step S3] Nozzle head control section 19
A nozzle lowering signal is sent to the upper and lower nozzle cylinders 14 to lower the nozzle 11 to the upper surface of the component 16 at the supply position.

[Step S4] Nozzle head control section 19
A component suction signal is sent to the electronic component 16 to cause the nozzle 11 to suction the electronic component 16.

[Step S5] Nozzle head control section 19
A nozzle raising signal is sent to the nozzle up/down cylinder 14 to raise the nozzle 11.

[Step S6] A variable i is initialized to 0.

[Step S7] Nozzle head control section 19
The rotation angle θ of the nozzle 11 is increased by Δθ from θ1 to θ2, and steps S7-1 to S7 are performed.
- Perform operations up to 4. That is, first set θ=θ1 and perform the operations from steps S7-1 to S7-4, then θ
=θ1+△θ and similarly steps S7-1 to S7-4
perform the following actions. Then, increase θ by △θ and θ=
Repeat until θ2. Note that θ1, θ2, and Δθ are constants stored in advance in the memory 21, and may be set to, for example, θ1=−30°, θ2=120°, and Δθ=0.05°.

[Step S7-1] The rotation angle θ of the nozzle 11 is sent to the nozzle head control section 19, and the θ-axis motor 7 is operated to rotate the nozzle 11 to the angle θ.

[Step S7-2] The distances S1 and S2 shown in FIG. 4 described above are read from the length measuring unit controller 20.

[Step S7-3] S1(i)=S1,
Write to the memory 21 as S2(i)=S2.

[Step S7-4] Increase the variable i by the value 1.

[Step S8] Set n=i-1.

[Step S9] From the measurement data S1(i)=S1(0) to S1(n) stored in the memory 21,
In a graph in which the horizontal axis is i (or θ) and the vertical axis is S1, the values i1 and i2 of i that give points of inflection are determined. That is, the value of the distance S1 or S2 obtained from the length measurement unit controller 20 when the electronic component 16 is rotated while being raised (maintained at the parallel beam irradiation position of the length measurement unit 15) is shown in FIG. As shown in FIG. Therefore, the value of i corresponding to the value of θ that gives these inflection points P1, Q1 or P2, Q2 is determined. (Note that the values of θ giving the inflection points P1 and P2 or the inflection points Q1 and Q2 are equal.)

[Step S10] The following formulas (1) and (2)
The vertical and horizontal lengths D and W of the component 16 are calculated by: In addition,
The dimensions of the component 16 can be calculated using these formulas because the electronic component 16 can be calculated at the rotation angle θc giving the inflection points P1 and P2.
This is because the longitudinal direction (D direction) of
This is because the horizontal direction (W direction) of the component 16 and the parallel light beam 15c are perpendicular to each other at .degree. D=S2(i1)-S1(i1)...(1)W=
S2(i2)-S1(i2)...(2)

003
7] [Step S11] Read out the nominal values Dn and Wn of the vertical and horizontal lengths of the component 16 and their allowable values △Da and △Wa stored in advance in the memory 21, and calculate the following equations (3) and (4). Determine whether or not you are satisfied. Then, when both equations are satisfied, steps S11-1 to S11-5 are executed, and otherwise, step S11-6 is executed. Dn-△Da≦D≦Dn+△Da ... (3) Wn-
△Wa≦W≦Wn+△Wn……(4)

[0038]
[Step S11-1] Calculate the suction rotational deviation amount θc and the suction position deviation amounts Dc and Wc shown in FIGS. 7 and 8. Here, the angle θc is the angle between the vertical direction of the component 16 and the X-axis direction of the XY robot 4. Further, the suction position deviation amount Dc is the deviation distance between the center position Oc of the component 16 and the axial center O of the nozzle 11, and is the distance along the vertical direction of the component 16, and the suction position deviation amount Wc is the deviation distance between the center position Oc of the component 16 and the axial center O of the nozzle 11. 16 along the lateral direction. The suction rotation deviation amount θc is determined in step S7-1.
When the part 16 is rotated to collect the data of S1(i) and S2(i) in S7-4, the part 16
It is equal to the rotation angle until the longitudinal direction of is perpendicular to the parallel light beam 15a, and is determined from the following equation (5). In addition, the adsorption position deviation amounts Dc and Wc are determined by the following equations (6) and (7), respectively. By these equations (6) and (7), Dc
, Wc are determined because S1(i1) and S2(i1) are the values of the distances S1 and S2 when the longitudinal direction of the component 16 is orthogonal to the parallel light beam 15c, and S1(i2) and S2(
This is because i2) is the value of the distances S1 and S2 when the lateral direction of the component 16 is orthogonal to the parallel light beam 15c. θc=△θ・i1+θ1
...(
5) Dc=(S1(i1)+S2(i
1))/2-S. ...(6)
Wc=(S1(i2)+S2(i2))/2−S. ...(7)

[Step S11
-2] From the memory 21, the mounting posture of the component 16 (rotation angle θ
r).

[Step S11-3] Considering the suction rotation deviation of the component 16, determine the rotation angle φ to orient the component 16 in an appropriate direction for mounting, and the suction position deviation amount D of the component 16.
Correction amount △x of the coordinate data for moving the component 16 to the appropriate mounting position by the XY robot 4 according to c, Wc
, △y. Since the rotation angle φ is the sum of the mounting attitude θr and the suction rotation deviation angle θc, the following formula (8) is obtained.
Also, the suction position deviation amount Dc of the component 16
, Wc and the X and Y axis directions of the XY robot 4 have the relationship shown in FIG.
It is determined by (10). φ=θc+θr
...(8)△x=Wc・sinφ+D
c・cosφ...(9)△y=Wc・cosφ+
Dc・sinφ...(10)

[Step S11-4] The nozzle rotation angle φ is sent to the nozzle head control section 19, and the nozzle 11 is rotated to the angle φ.

[Step S11-5] A command to move the nozzle 11 by (-△x, -△y) in the X-axis and Y-axis directions is sent to the XY robot control unit 18, and the XY robot 4 is moved from the current position to the X-axis. , -Δx and -Δy in the Y-axis direction, respectively.

[Step S11-6] An error flag is set.

As described above, the component mounting device of this embodiment can perform image processing when using a television camera by the signal from the length measuring unit 15, which has a simple structure consisting of a light projecting section and a light receiving section. By the process described above, which is extremely simple in comparison, and without bringing a claw or the like into contact with the component 16, the correction amounts θc, Δx, and Δy for the deviation in position or orientation of the component 16 when it is picked up can be determined. By making corrections based on this correction amount, part 1 can be fixed regardless of the deviation during suction.
6 can be accurately positioned at a desired position and mounted on an electronic circuit board or the like.

Furthermore, if the component 16 is not picked up horizontally, it is determined in step S11 that it is abnormal and an error is determined in step S11-6. This prevents parts from being picked up, corrected, and mounted in an abnormal state.

In the above embodiment, one length measuring unit is used, but another length measuring unit may be provided orthogonally to each other.

[0047]

[Effects of the Invention] As is clear from the above description, the component mounting device of the present invention is based on data obtained from a simple configuration consisting of a light emitter and a light receiver, and is extremely simple compared to image processing. Through processing, it is possible to determine the amount of correction for the deviation in the position or orientation of the part when it is picked up, without touching the part with a nail or the like, and by performing correction based on this amount of correction, it is possible to correct the deviation in the position or orientation of the part when it is picked up. Components can be accurately positioned at desired positions and mounted on electronic circuit boards, etc.

[0048] Therefore, the following various effects can be achieved. (1) Since it is a non-contact method, it does not cause damage to electronic components. (2) Since the size of the part that can be detected is determined by the width of the parallel light beam, there are few restrictions on the size of the part to be detected. (3) It is also possible to detect defective component shapes and suction errors (chip standing). (4) Since the device is small and the nozzle head is compact, the movement range of the nozzle head can be expanded, and there are no restrictions on the operation during suction and mounting. (5) Since signal processing is simple, the memory capacity and the like are small, making the device less expensive and processing speed faster, thereby shortening the mounting takt time. (6) Since optical systems such as mirrors and prisms are not required, the system is highly reliable and accurate, and requires no adjustment or maintenance.

[Brief explanation of drawings]

FIG. 1 is a perspective view of a component mounting device.

FIG. 2 is a sectional view of a nozzle head.

FIG. 3 is a partial side view of the nozzle head for explaining the length measuring unit.

FIG. 4 is a bottom view of the nozzle head for explaining the length measuring unit.

FIG. 5 is a block diagram showing the configuration of a controller.

FIG. 6 is a PAD diagram showing the operation procedure of the controller.

FIG. 7 is a diagram for explaining the relationship between the rotation of parts and the signal output by the light receiving section.

FIG. 8 is a diagram for explaining the amount of adsorption deviation of parts.

[Explanation of symbols]

3 Nozzle head 11 Nozzle 15a　Light projection part 15b Light receiving part 15c Parallel light beam 16 Parts

Claims (1)

[Claims] 1. A nozzle head for rotatably and vertically movably supporting a nozzle that removably holds a component with a suction section vertically downward; In a component mounting device that positions and attaches a component by moving it in the horizontal direction, a light projecting unit that emits a parallel light beam in the horizontal direction on one side of an area in which the component held by the nozzle moves up and down; A component characterized in that the nozzle head is provided with a light receiving part that receives the parallel light beam on the opposite side of the area with respect to the light projecting part and converts the brightness and darkness of the light into an electrical signal in accordance with the light receiving position. Mounting device.