JPH0964598A - Aligning method for automatic assembling system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an aligning method for an automatic assembling system in which the parts can be assembled while being aligned highly accurately with no limit to dimensions thereof. SOLUTION: The attitudes of a body 10 to be assembled and an assembling parts 11 are detected by measuring the position of more than one measuring part for each of them. The shift of body 10 to be assembled from the assembling position of assembling parts 11 is then determined based on the decision results of the attitude. Since the assembling parts 11 is aligned by means of an X-Y-X-θ robot while taking account of the shift thus determined, it can be assembled at an accurate assembling position into the body 10 to be assembled while judging the relative positional relationship between the body 10 and the parts 11 highly accurately regardless of the dimensions of the assembling parts 11.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of aligning an automatic assembling apparatus.

[0002]

2. Description of the Related Art Generally, a positioning chuck method and a method using image recognition have been widely adopted as a method of aligning a small component such as an electronic component in an automatic assembling apparatus.

For example, in the position recognition method for electronic components disclosed in Japanese Patent Laid-Open No. 4-42600, the assembled component is placed on a stage in a state of being released from a suction nozzle that holds and conveys the assembled component, and an entire image of the assembled component is displayed on a television. The position of the assembled component is determined by detecting the posture of the assembled component within the field of view of the camera.

Further, the method of detecting the inclination of an IC, which is an electronic component, disclosed in Japanese Patent Laid-Open No. 6-28473 is first described as IC.
The center of the IC is determined from the center of gravity of the pin to extract the center of gravity of the pin to detect the tilt for alignment.

Further, as shown in FIG.
Cylinder 10 by putting assembly part 103 on 01
A method of moving the rod 2 in the direction of arrow A to bring the assembly component 103 into contact with the positioning block 100 and mechanically aligning the assembly component 103 is also widely used.

[0006]

However, in the case of the position recognition method for electronic parts disclosed in the above-mentioned Japanese Patent Laid-Open No. 4-42600, it is necessary to put all the parts to be assembled into the field of view of the television camera. There is a limit on the size of an assembly part that can carry out an assembly work with high accuracy, and it is necessary to lower the image pickup magnification of a TV camera for an assembly part having a larger size, which causes a problem of lowering the assembly accuracy. is there.

In the case of the IC tilt detection method disclosed in Japanese Patent Laid-Open No. 6-28473, the IC is divided into two stages.
Since the pins and the center are detected, the time required for the assembling work becomes long and the assembling efficiency is reduced.

Further, in the case of the method shown in FIG. 7, when the assembly part 103 is mechanically aligned, the assembly part 1
Since 03 is applied to the positioning block 100, there is a problem that the assembly component 103 may be damaged.

Further, in any of the above-described method of recognizing the position of the electronic component and the method of detecting the inclination of the IC, the position of the assembled component in the rotational direction is to be corrected. , X direction, Y when rotated in a state where these actual center points are deviated
It does not consider the situation that the positional displacement in the direction occurs,
On the contrary, there is a problem that the misalignment in the X and Y directions becomes large by performing the correction around the rotation axis.

Therefore, the present invention provides a positioning method for an automatic assembling apparatus, which is capable of performing positioning with high accuracy without being restricted by the size of the assembled parts.

[0011]

According to the first aspect of the present invention,
Positioning of the assembly parts in the supply part is held by the part holding part provided in the transfer part and taken out, and the taken out assembly parts are moved to the assembly position of the assembly target to assemble the assembled parts In the method, the positions of at least two measuring portions of each of the assembled body and the assembled component are measured to detect the postures of the assembled body and the assembled component, and the detection results of the postures of the assembled body and the assembled component are detected. Amount of deviation of the assembling component with respect to the assembling position of the body to be assembled is determined based on the base, and the assembly component is positionally moved according to the amount of displacement obtained by the component holder to be assembled at the assembling position of the body to be assembled. It is characterized by.

According to a second aspect of the present invention, in the method of aligning an automatic assembling apparatus according to the first aspect of the invention, the positions of at least two measuring portions of the assembly component are detected by one measurement. Based on the detected position information of each measured portion, three displacement amounts including an X direction, a Y direction, and a displacement angle between the reference posture and the actual posture of the assembled component are obtained, and the component holding unit detects the displacement of the assembled component. The holding reference point and the actual holding point of the assembled part when the assembling part is rotated by the assembling angle in a state where the holding reference point and the actual holding point do not match The movement position of the assembled component is the same as when the assembled component is rotated by the assembly angle while the assembled component is held in the posture where It becomes the X direction, and calculates a correction amount in the Y direction and the angular direction, and is characterized in determining the amount of deviation assembly position of the object to be assembled body of the assembly component.

According to a third aspect of the invention, in the method for aligning an automatic assembling apparatus according to the first or second aspect of the invention, the position of at least two measuring portions of the assembled component is detected by holding the component. It is characterized in that the assembled parts are taken out from the supply part and held by the part.

According to the method of aligning the automatic assembling apparatus according to the first aspect, the assembly parts in the supply section are held and taken out by the part holding section provided in the transfer section, and moved to the assembly position of the assembly object. At the time of assembling the lever to the assembling position of the assembling parts, first, the positions of at least two measuring portions of the assembling body and the assembling parts are measured to detect the postures of the assembling body and the assembling parts, and then, Based on the detection results of these attitudes, the amount of deviation of the assembled parts with respect to the assembling position of the body to be assembled is obtained, and the component holding unit performs the positional alignment movement of the assembled parts according to the obtained amount of deviation. Therefore, regardless of the size of the assembly parts, it is possible to accurately determine the relative positional relationship between the assembly object and the assembly parts with high accuracy. It can be assembled viewed with a component in the assembly position of the assembly body.

According to the position aligning method of the automatic assembling apparatus according to the second aspect, in the position aligning method of the automatic assembling apparatus according to the first aspect of the present invention, the positions of at least two or more measuring portions of the assembly parts are set. Each is detected by one measurement, and based on the detected position information of each measured portion, three displacement amounts including the X direction, the Y direction, and the displacement angle between the reference posture and the actual posture of this assembled component are obtained. further,
When the assembly holding part holds the assembled part in a posture in which the holding reference point of the assembled part does not coincide with the actual holding point, and when the assembled part is rotated by the assembling angle, The moving position of the assembled component is the same when the assembled component is rotated by the assembly angle while the assembled component is held in the posture in which the holding reference point and the actual holding point match. And the amount of correction in the angular direction are calculated, and the amount of deviation of the assembling component with respect to the assembling position of the body to be assembled is obtained from these, so that the assembling component is held at a position displaced from its holding reference point. Even in this case, after detecting the posture of the assembly component, by rotating the assembly component according to the correction amount in the angular direction, Accurately, yet can be assembled the assembly parts in good condition of the cycle time is short efficiency assembled position of the assembly body.

According to a third aspect of the automatic assembly apparatus alignment method of the present invention, in the automatic assembly apparatus alignment method according to the first or second aspect of the present invention, at least two or more measurement portions of the assembly parts are measured. The position detection is performed while the assembled parts are taken out from the supply part and held by the part holding part, so that the posture detection including the handling error by the part holding part can be performed, and the assembled parts can be extremely accurately. It can be assembled at the assembly position of the assembled object.

[0017]

Embodiments of the present invention will be described below in detail.

(Embodiment) FIG. 1 schematically shows an automatic assembling apparatus according to a first embodiment of the present invention. This automatic assembling apparatus is arranged on a base 1 and on the base 1. X-Y-Z-θ robot 2 that is a component holding unit and X on the base 1
-Y-Z-? Conveyor 3, which is arranged below the robot 2 and constitutes a transfer unit for conveying the assembly target object 10, and the necessary assembly parts 11 are set in advance on the base 1 so that they can be supplied. It is equipped with a pallet 5 which is a supply unit to be stored and a pallet changer 4 which is provided with a plurality of pallets 5 and is automatically changed.

The X-Y-Z-.theta. Robot 2 has an X-axis arm 2a, a Y-axis arm 2b, a Z-axis arm 2c and a hand 2d rotatably attached downward from the Z-axis arm 2c and a suction nozzle 9. And the assembled component 1 mounted around the hand 2d and held by the suction nozzle 9.
1 and a ring illumination 12 for illuminating 1.

Instead of the XYZ-θ robot 2, a horizontal articulated robot, a SCARA type robot or the like can be used.

A television camera 6 for detecting the posture of the assembly object 10 is arranged in a portion of the XYZ-θ robot 2 where only the XY axes are concerned. The coaxial epi-illumination 8 that irradiates the measurement point of the assembly body 10 is arranged.

On the base 1, the XYZ is placed.
A television camera 7 for detecting the measurement point of the assembled component 11 held by the suction nozzle 9 attached to the lower end of the hand 2d of the θ robot 2 is arranged. A coaxial epi-illumination 13 is arranged to illuminate the measurement point of the component 11.

Below the base 1, a main controller 20 which is a control means for controlling the overall operation of the automatic assembling apparatus, and a robot for mainly controlling the operation of the XYZ-θ robot 2 are provided. Controller 21 and assembled body 1 imaged by the TV camera 6 and the TV camera 7
0 and an image processing device 22 for processing the image signal of the assembly component 11.

FIG. 2 shows an arrangement in which the assembly parts 11 are assembled to the assembly body 10 in association with the X-Y axes. Measurement marks 10a and 10b used to detect the posture of the assembly target 10 are attached to both corners of the assembly target assembly 10 on the diagonal line. Further, the assembly component 11 is formed, for example, in a pentagonal shape in plan view, and the measurement mark 11a used for detecting the posture is located at a position near the corner of the upper side and a position near the corner of one side shown in FIG. ,
11b is attached. The measurement marks 10a, 10b
The measurement marks 11a and 11b are indicated by circles in FIG. 2, but may have any shape as long as they can be processed by the image processing device 22.

FIG. 3 shows a control system of the automatic assembling apparatus. The main controller 20 for controlling the entire operation includes the television camera 6 and the coaxial epi-illumination 8, the television camera 7 and the coaxial epi-illumination 13. The pallet exchange 4, the robot controller 21 for controlling the XYZ-θ robot, the ring illumination 12, and the image processing device 22 are connected.

The main controller 20 is provided with the measurement mark 10 of the assembly body 10 and the assembly component 11.
a, 10b and the position information and dimensions of the measurement marks 11a and 11b, the assembling position and the assembling angle of the assembling component 11, the information of the pallet 5, and the operation sequence of the automatic assembling device is also stored, An operation command is sent to the robot controller 21 based on the information.

The robot controller 21 moves downward from the X-axis arm 2a, the Y-axis arm 2b, the Z-axis arm 2c and the Z-axis arm 2c of the XYZ-θ robot 2 based on the operation command from the main controller 20. The hand 2d and the suction nozzle 9 attached toward each are driven.

Further, the main controller 20 controls the image processing device 22 to execute the image processing at a necessary timing, and receives and stores the image-processed information.

Next, a method of aligning the assembly body 10 and the assembly component 11 by the above-described automatic assembly apparatus will be described with reference to FIGS. 4 to 6.

FIG. 4 shows the measurement marks 10a, 10b or the measurement marks 11a, 11b of the object 10 to be assembled or the parts 11 to be assembled by the TV camera 6 or the TV camera 7.
3 shows an image 30 obtained by picking up the image and performing image processing on the image processing device 22. In this case, the measurement mark 10a from the imaging center 31 of the TV camera 6 or the TV camera 7,
The following description will be made assuming that the deviation in the X direction from the reference point 32 of the measurement mark 10b or the measurement marks 11a and 11b is Xa and the deviation in the Y direction is Ya.

Further, FIG. 5 shows that the assembled component 10 shown in the posture W3 by holding the assembled component 11 in the actual posture W2 with respect to the assembled component 11 in the theoretically accurate posture W1 with respect to the XY axes. It shows the state of assembling to. Further, FIG. 6 is an enlarged view of a main part of FIG. 5, and a reference point P for calculating a correction operation amount described in detail later.
1 to P10 are entered.

Next, a specific example of a method of aligning the assembly object 10 and the assembly component 11 by the above-described automatic assembly apparatus will be described.

First, the body 10 to be assembled is conveyed to a predetermined assembly position by the conveyor 3 and stopped. Next, the robot controller 21 based on the operation command from the main controller 20 drives the X-axis arm 2 a and the Y-axis arm 2 b of the XYZ-θ robot 2 to mount the television camera 6 on the assembly target 10. Measurement mark 10a
Is moved above the position where it should theoretically exist, and the television camera 6 captures an image of the measurement mark 10a and sends an image pickup signal to the image processing device 22 for image processing and display. Similarly, the television camera 6 is attached to the measurement mark 10b of the body 10 to be assembled.
Is moved above the position where it should theoretically exist, and the television camera 6 captures an image of the measurement mark 10b and sends an image pickup signal to the image processing device 22 for image processing and display. In this way, the positions of the measurement marks 10a and 10b on the assembly target 10 are detected.

Here, the assembled body 10 as described above is used.
The theoretical two points in 3 are detected and replaced with the obtained two points to set a local coordinate system different from the original global coordinate system of the XYZ-θ robot 2. After that, the position of the assembly object 10 is corrected by using the local coordinate system to correct the deviation of the posture.

Next, the pallet exchange 4 is operated,
After the pallet 5 having the assembly parts 11 mounted thereon is taken out and placed at a predetermined position, the robot controller 21 based on the operation command from the main controller 20
The XYZ-θ robot 2 is operated to move the suction nozzle 9
Is placed on the holding reference point of the assembled component 11 on the pallet 5, and the Z-axis arm 2c is lowered in this state to suck and hold the holding reference point of the assembled component 11 by the suction nozzle 9. After that, the Z-axis arm 2c is lifted, the assembly component 11 is taken out from the pallet 5, and the X-
The YZ-θ robot 2 is operated and the measurement mark 11 of the assembly component 11 suction-held by the suction nozzle 9 is held.
The reference point of a is theoretically moved to a position that is the center of the image picked up by the TV camera 7. In this state, the television camera 7 captures an image of the measurement mark 11a and sends an image pickup signal to the image processing device 22 for image processing and display. Next, the XYZ-θ robot 2 uses the robot controller 21 to measure the measurement mark 1
The reference point of 1b theoretically moves to a position that is the center of image pickup of the television camera 7, and in this state, the television camera 7 takes an image of the measurement mark 11b and sends an image pickup signal to the image processing device 22 for image processing and display. In this way, the positions of the measurement marks 11a and 11b of the assembly component 11 are detected.

In this way, the positions of the measurement marks 10a and 10b of the assembly object 10 and the assembly component 11 are set.
After detecting the positions of the measurement marks 11a and 11b, the main controller 20 executes the detection of the posture of the assembly component 11 sucked and held by the suction nozzle 9 and the calculation of the correction operation amount based on these signals.

Hereinafter, the detection of the posture of the assembly part 11 and the calculation of the correction operation amount will be described in detail with reference to FIGS. 4 to 6.

Measurement points P2 (X1, Y) corresponding to the measurement marks 11a, 11b in the posture W1 of the assembly part 11
1) and P3 (X2, Y2), the straight line L1 has an inclination of M1 and an angle of X1 with the X axis, M1 = (Y1−Y2) / (X
1-X2), and .theta.1 can be expressed by equation 1.

[0039]

[Equation 1]

Next, the measurement point P2 (X1, Y1) and the measurement point P3 (X2, Y2) in the posture W1 of the assembly part 11 are described.
) Of the ideal position from (X3, Y3), (X4
, Y4), the actual posture W2 of the assembled component 11
At measurement points P5 (X5, Y5), P6 (X6, Y6)
) Is X5 = X1 + X3, Y5 in the XY coordinate system.
= Y1 + Y3, X6 = X2 + X4, Y6 = Y2 + Y4
It can be expressed by the following relationship.

Further, the posture W2 of the actual assembly part 11
At measurement points P5 (X5, Y5), P6 (X6, Y6)
), The inclination of the straight line L2 is M2, and the angle with the X axis is θ3
Then, M2 = (Y5-Y6) / (X6-X6) can be expressed, and .theta.3 can be expressed by equation 2.

[0042]

[Equation 2]

As a result, the angle difference θ5 between the posture W1 and the posture W2 of the assembled component 11 is θ5 = θ1
−θ3.

Next, the assembly parts 11 in the case of the posture W1
From the holding reference point P1 (X10, Y10) to the measurement point P3 (X2,
Y2) to X7 and Y7, respectively.
Then, the distance R1 between the holding reference point P1 and the measurement point P3 and the angle θ7 formed by these two points with the X axis are given by the following equations 3 and 4
Can be represented by

[0045]

(Equation 3)

[0046]

(Equation 4)

Assembly parts 11 in case of actual posture W2
Holding reference point P4 (X9, Y9) and measuring point P6 (X6,
The inclination θ9 of the straight line connecting to Y6) is θ9 = θ7−θ5.

Assembling parts 11 for posture W2
From the measurement point P6 (X6, Y6) of the holding reference point P4 (X9
, Y9) to the X-axis and Y-axis
, Y8, the assembled component 11 does not change in size between the posture W1 and the posture W2, and the holding reference point P1
The distance between the measuring point P6 and the measuring point P6 is
Since it is equal to the distance R1 from X8 = R1 cos θ9
, Y8 = R1 sin θ9. Therefore, the holding reference point P
The position of 4 (X9, Y9) is X9 = X6-X8, Y9 =
It can be represented by Y6-Y8.

Next, the assembly parts 11 in the case of the posture W1
From the holding reference point P1 (X10, Y10) of the mounting reference point P4 (X9, Y9) of the assembled component 11 in the actual posture W2.
) To the X-axis and Y-axis directions by X11 and Y11, respectively.
Then, X11 = X9-X10 and Y11 = Y9-Y10 can be expressed.

Next, when the actual posture of the body 10 to be assembled has an inclination of .theta.11 with respect to the ideal posture as shown in FIG. Need to rotate.

The holding reference point P1 (X) of the assembled component 11 in the posture W1
(10, Y10) as a center, the holding reference point P4 is moved by an angle θ11. At the moving point P7 (X13, Y13), the distances in the X axis direction and the Y direction from the holding reference point P1 are X12 and Y12, respectively. Then, X12 = X11cos θ11−Y11si
nθ11, Y12 = X11sin θ11−Y11cos θ11.

In FIG. 6, point P9 (X19, Y19)
Indicates the moving position of the measuring point P6 when the assembly part 11 in the case of the posture W2 is rotated by the angle θ11 about the holding reference point P1 (X10, Y10), and the point P8 (X18, Y10)
18) shows the moving position of the measuring point P5 when the assembly component 11 in the posture W2 is rotated by the angle θ11 about the holding reference point P1 (X10, Y10).

As described above, the distances X12 and Y12 are
The deviation amount is obtained when the assembled component 11 in the actual posture W2 is held at the holding reference point P1 and is rotated about the θ axis by the X-Y-Z-θ robot 2 by the angle θ11.

Therefore, as shown in FIG. 5, the assembled component 11 in the posture W1 is moved by a distance of X14 in the X-axis direction and Y14 in the Y-axis direction, and further rotated by an angle θ11 about the θ-axis. When it is desired to assemble the object to be assembled 10 in the state of W3, ideally the XYZ-θ robot 2 holds the assembly component 11 as shown in FIG.
It is necessary to move to (X15, Y15) and rotate about the θ axis by the angle θ11, but when it is displaced from the ideal position like the assembly component 11 in the actual posture W2. Needs to be corrected. Incidentally, P11 and P12 shown in FIG. 5 indicate measurement points in the state of posture W3.

Now, the moving point after the correction calculation is P13 (X16,
Y16), the coordinates X16 and Y16 are X16 = X15-X1
2, Y16 = Y15-Y12.

X16 = X15-X12, Y16 = Y15-Y12
Note that X12 and Y12 in the formula are values of the global coordinate system in the XYZ-θ robot 2, and other than these are local coordinate systems corresponding to the posture of the assembly target 10 described above. It is necessary.

Then, by moving the assembly part 11 to the movement point P13 (X16, Y16) by the XYZ-θ robot 2 and rotating it by the angle (θ11 + θ5), the position where the assembly part 11 should originally be assembled is set. Will occupy.

By moving the XYZ-θ robot 2 to the position of the data obtained as described above, rotating the θ-axis, and lowering the Z arm 2c, the suction nozzle 9 is moved.
Also descends, and the assembly component 11 moves onto the assembly target body 10. After this, the suction operation of the suction nozzle 9 is terminated and the Z arm 2c is raised. Then, the assembly component 11 is assembled to the assembly target body 10.

In this way, the assembly component 11 can be assembled to the assembly body 10 with high precision.

[0060]

According to the first aspect of the present invention, the assembled parts are accurately covered while accurately determining the relative positional relationship between the assembled body and the assembled parts regardless of the size of the assembled parts. It is possible to provide a method for aligning an automatic assembling apparatus that can be assembled at the assembly position of an assembly.

According to the second aspect of the present invention, including the case where the assembled component is held at a position deviated from the holding reference point, the assembled component is always accurately and efficiently in a short cycle time. It is possible to provide a position aligning method of an automatic assembling apparatus capable of assembling the assembly at the assembly position of the assembly target body.

According to the invention of claim 3, in addition to the effect of the invention of claim 1 or 2, posture detection including a handling error by the component holder can be performed, and the assembled component can be extremely highly accurate. It is possible to provide a method for aligning an automatic assembling apparatus that can be assembled at the assembly position of the assembly target.

[Brief description of drawings]

FIG. 1 is a schematic perspective view showing an embodiment of an automatic assembly apparatus of the present invention.

FIG. 2 is an explanatory diagram showing a positional relationship between an assembly component and an assembly object according to the present embodiment.

FIG. 3 is a block diagram showing a control system in the present embodiment.

FIG. 4 is an explanatory diagram showing a captured image of a measurement mark according to the present embodiment.

FIG. 5 is an explanatory diagram for obtaining a correction amount for an assembly position of an assembly component according to the present embodiment.

6 is a partially enlarged explanatory view of FIG.

FIG. 7 is an explanatory view showing a conventional method of aligning assembled parts.

[Explanation of symbols]

 1 Base 2 XYZ-θ Robot 5 Pallet 6 Television camera 7 Television camera 8 Coaxial epi-illumination 9 Adsorption nozzle 10 Assembly object 11 Assembly parts 12 Ring illumination 13 Coaxial epi-illumination 20 Main controller 21 Robot controller 22 Image processing Device 31 Center of camera 32 Reference point

Claims (3)

[Claims] 1. An automatic system for holding an assembly component in a supply unit by a component holder provided in a transfer unit and taking out the assembly component, moving the assembly component thus extracted to an assembly position of an assembly target body, and assembling the assembly component. In a method of aligning an assembling apparatus, the positions of at least two measuring portions of each of the assembling body and the assembling parts are measured to detect the postures of the assembling body and the assembling parts to detect the assembling body and the assembling parts. Based on the detection result of the posture, obtain the amount of deviation of the assembly parts with respect to the assembly position of the assembled body,
A positioning method for an automatic assembling apparatus, comprising: performing an alignment movement of the assembly component according to a displacement amount obtained by the component holding unit and assembling the assembly component at an assembly position of an assembly object. 2. The positions of at least two or more measurement parts of the assembly part are detected by one measurement, and the reference attitude and the actual attitude of the assembly part are detected based on the detected position information of each measurement part. The state in which the assembled component is held in such a posture that the holding reference point of the assembled component does not coincide with the actual holding point by the component holder while the three displacement amounts including the X direction, the Y direction, and the displacement angle are obtained. When the assembled component is rotated by the assembly angle and the component holding section holds the assembled component in a posture in which the holding reference point of the assembled component and the actual holding point of the assembled component match, assemble the assembled component. The correction amount in the X direction, the Y direction, and the angular direction, at which the moving position of the assembled component is the same as when the assembly is rotated by an angle, is calculated, and the assembled component is assembled. 2. A method for aligning an automatic assembling apparatus according to claim 1, wherein a displacement amount of the case with respect to an assembling position is obtained. 3. The detection of the positions of at least two measurement portions of the assembly component is performed while the assembly component is taken out from the supply unit and held by the component holder. A method for aligning the described automatic assembly apparatus.