JPH11129175A - Articulated robot - Google Patents

Abstract

PROBLEM TO BE SOLVED: To shorten a total time required for movement of a workpiece even as orientation of a workpiece is effected and to improve the movement efficiency of a workpiece. SOLUTION: An installation part 8 for a workpiece 20 and a sensor part 10 to detect a positional deviation of a workpiece 20 are arranged at movement parts 2 and 3 of which a reticulated robot 1 consists. With the workpiece 20 installed at the installation part 8 for the moving parts 2 and 3, detection by the sensor part 20 and movement by the movement parts 2 and 3 are constituted so as to be practicable.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to an articulated robot. More specifically, the present invention relates to an improvement of an articulated robot that transports a work such as a semiconductor wafer.

[0002]

2. Description of the Related Art An articulated robot is used to move a work such as a semiconductor wafer from a cassette to a process apparatus for performing a photo process, film formation, etching, and the like. The robot 100 includes, for example, a base 101, a first arm 102, a second arm 103, and a hand unit 104 as shown in FIG. 9A, and moves the work 107 from the cassette 105 to the process device 106.

In the case where a semiconductor wafer is used as the material of the work 107, for example, the direction of the work 107 is fixed when performing a heat treatment or a film forming process due to the directionality of the crystal of the semiconductor wafer. It is necessary to Therefore, when moving the workpieces, the orientations of the workpieces 107,..., 107 placed on the process apparatus 106 must be oriented in the same direction.

Accordingly, a mark such as a notch or a D-flat is provided at a predetermined position on the edge of the work 107, and a work rotating device called an aligner 108 having a means for detecting the mark is mounted on a cassette 105 as shown in FIG. And the process device 106. FIG.
The work 107 taken out from the cassette 105 by the hand unit 104 as shown in FIGS. 9A to 9C is temporarily placed on the aligner 108 (FIG. 9D), and rotated to a position facing a predetermined direction. After the orientations are aligned, it is moved and placed on the process device 106 (FIG. 9E,
(F)).

[0005]

However, for example, a series of work transfer devices arranged as shown in FIG. 10 (the base 101 in this case, the work is transferred to each of the process devices 106,... However, there is a problem that it takes a long time to transport the work 107 in some cases. That is, each work 107,
.., 107 are oriented in a predetermined direction.
8 while the two cassettes 105, 105 and the plurality of process devices 106,
, 106, only one aligner 108 is arranged. Therefore, for example, the cassette 10 on the lower side in FIG.
When moving the work 107 from the fifth to the lowermost process device 106, the work 107 must be passed through the aligner 108. In such a case, the moving distance of the robot 100 becomes long, and the movement of the work 107 It takes time.

Further, even when the workpiece 107 is moved along a path having a short moving distance (for example, from the cassette 105 on the upper side in the figure to the process device 106 located on the upper side in the figure), the orientation is ended after the orientation starts. Since the work 107 cannot be moved until this time, the robot 100 must wait until the work is completed, and the movement of the work 107 always requires a certain time or more.

Accordingly, an object of the present invention is to provide an articulated robot capable of shortening the total time required for moving a work while performing work orientation and improving the movement efficiency of the work.

[0008]

In order to achieve the above object, according to the first aspect of the present invention, a second moving unit is movably held via a joint with respect to a first moving unit, and a second moving unit is provided. A multi-joint robot in which a workpiece is set on a workpiece position shift amount detecting means by a hand unit provided at a tip end of the unit and the position shift amount of the work is detected by the work position shift amount detecting means. The moving part to be configured is provided with a work setting part and a sensor part for detecting a positional deviation of the work so that the work can be detected by the sensor part and moved by the moving part in a state where the work is set in the moving part setting part. Make up.

Therefore, the work set in the setting section is
The workpiece is moved by the moving unit at the same time as the work displacement is detected by the work displacement detecting means. That is, according to the articulated robot, the movement of the workpiece and the detection of the displacement of the workpiece can be simultaneously performed independently of each other.

[0010] In the articulated robot according to the second aspect, the installation section has a rotating means for rotating the installed work, and the sensor section is a sensor for detecting an end position of the work. Therefore, the work set in the setting part is rotated by the rotating means, and a mark such as a notch provided in the end is detected by the sensor.

[0013] In the articulated robot according to the third aspect, the second moving section is constituted by the second arm and the third arm connected to the second arm, and the installation section and the sensor section are formed by the first moving section or the first moving section. It is provided on two arms. Therefore, three nodes of the second arm, the third arm, and the hand portion are formed beyond the first moving portion, and the workpiece is held by rotating these nodes as appropriate, or held by the hand portion. Correctly placed work.

In the articulated robot according to the fourth aspect, the first moving part is a slide moving part, and the second arm, the third arm, and the hand part are rotatably connected to the slide moving part by the joint part. Become. Therefore, the second arm,
The third arm and the hand unit are rotatable with respect to the slide moving unit, and can move the work while the slide moving unit is sliding.

[0013] In the articulated robot according to the fifth aspect, the first moving section is a rotary table, and the second arm, the third arm, and the hand section are rotatably connected to the rotary table by the joint section. Therefore, the second arm, the third arm
The arm and the hand unit are rotatable with respect to the rotary table, and can move the work while the rotary table is rotating.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The configuration of the present invention will be described below in detail based on an example of an embodiment shown in the drawings.

FIG. 1 shows an embodiment of the articulated robot of the present invention. The articulated robot 1 includes a first moving unit 2
And a second moving unit 3 and a hand unit 4 for holding the work 20
And a scalar (horizontal joint) type multi-joint moving unit. Here, the first moving unit 2 is a slide moving unit 21, and the second moving unit 3 and the hand unit 4 are rotatably connected to the slide moving unit 21 by joints 23 and 34. The slide moving unit 21 moves linearly as shown, and is provided so as to position the articulated robot 1 in front of each of the cassettes 5 and 5 and each of the process devices 6,. The second moving unit 3 includes a second arm 31 and a third arm 32 connected to the second arm 31. Then, the work 20 is set on the work position shift amount detecting means 13 by the hand unit 4 provided at the tip of the second moving unit 3, and the work position shift amount of the work 20 is detected by the work position shift amount detecting means 13. Have been able to.

In the articulated robot 1 of the present embodiment, the moving part 2 (or the moving part 3) constituting the articulated robot 1 is provided with an installation part 8 of the work 20 and a sensor part 10 for detecting a displacement of the work 20. Is provided so that detection by the sensor unit 10 and movement by the moving unit 2 are possible in a state where the work 20 is installed on the setting unit 8 of the moving unit 2 (or the moving unit 3). The sensor unit 10 here is a sensor that detects an end position of the work 20. In the articulated robot 1 in which the second moving unit 3 includes the second arm 31 and the third arm 32 as in the present embodiment, the installation unit 8 and the sensor unit 10 may be provided in the first moving unit 2. Alternatively, it may be provided on the second arm 31.

The installation section 8 is provided so as to be vertically movable as shown in FIG. 8 so that the work 20 can be transferred to and from the hand section 4, and the work 20 can be fixed by its tip. It is provided as follows. The means for fixing the work 20 is not particularly limited, but is provided so as to be able to be sucked here. Therefore, work 2
When the hand unit 4 holding 0 is positioned right above the installation unit 8, the installation unit 8 rises and sucks and receives the work 20, while it rises again after the orientation is completed, and this time the work 20 is hand-held. Transfer to part 4 and hold again.

Further, the installation section 8 is provided so as to move independently of the movement of the moving section 2 and the moving section 3. That is, a rotating means for rotating the work 20 is provided so that the orientation on the installation unit 8 can be performed independently of the movement when the moving units 2 and 3 move the work 20. The rotating unit is a turntable driven by a driving unit 9 such as a motor. Further, the articulated robot 1 is provided with an analysis device 11 for analyzing data obtained by the sensor unit 10, and the installation unit 8, the driving unit 9, the sensor unit 10, and the analysis device 11 constitute an aligner 7. ing. The aligner 7 is provided so as to be able to detect both the displacement of the work 20 in the rotational direction and the displacement of the center position. In this embodiment, the aligner 7 functions as the work position displacement amount detecting means 13. Have Therefore, an example of the aligner 7 will be described below, and an outline of the orientation function of the aligner 7 will be described first.

The aligner 7 rotates the placed work 20.
Notch 20a (or
(D cut called orientation flat)
Is detected, all the placed workpieces 20,
…, Oriente to adjust the direction and holding angle of 20
It has an optional function. Aligner shown in Figure 2
At 7, the installation section 8 has a turntable (spindle)
However, the driving means 9 includes a stepping motor (including a reduction gear).
However, a line type CCD is used for the sensor unit 10.
Have been. This orientation function is provided by the driving means 9.
The installation unit 8 is rotated by the
Measurement and analysis device 11 consisting of a microprocessor, etc.
Analysis of multi-point data by
It is configured. Therefore, using this aligner 7
To perform the orientation of the work 20, first place
The completed work 20 is rotated together with the turntable 8, and the
The outer peripheral portion of the work 20 is arranged at a pitch of 1 mm by the sensor portion 10.
to scan. Here, the notch 20a on the outer peripheral part of the work is detected.
Do not stop the rotation of the work 20 immediately
Then, data for at least one rotation is collected (FIG. 3).
In addition, data processing is performed simultaneously with scanning.
Point moved 0.8 mm from 0 mm moving average
Is determined to be near the notch 20a. And in FIG.
A data string consisting of four points near the notch 20a shown
Then, the center 20c of the work 20 is obtained by calculation. this
First, P_n-1And P_{n + 2}Due to misalignment of the work 20
Is calculated, and then a right-angled isosceles triangle is formed.
P located on the edge of the notch 20a _nAnd P_{n + 1}And from
The angle φ of the helix 20a is obtained by calculation. Also, this operation
At the same time, set to the specified position based on the vicinity of the notch 20a.
The placing section 8 is rotated. Furthermore, for estimating the shape of the notch 20a
Rotate by a very small amount calculated from
Make corrections. As a result, the notch 20a reaches the predetermined position.
Moved to the same orientation to finish orientation
I do. The above calculation process is briefly summarized and shown in the table.
This is shown in FIG. 5 as an example.

Further, using the data obtained by the sensor section 10, it is possible to measure the deviation from the center when the work 20 is placed on the installation section 8. The data obtained by the above-described optical measurement by the line CCD 10 is used for the detection of the displacement, but the data corresponding to the notch 20a used in the orientation is deleted. First, as shown in FIG. 6, two arbitrary points P1 and P2 on the circumference of the work 20 separated by about 180 degrees are extracted, and a straight line connecting the two points is defined as N1, and a midpoint between P1 and P2. A normal line of N1 passing through M1 (that is, a perpendicular bisector of the line segment P1P2) is defined as N2. Another two points P3 and P4 are similarly extracted, and a straight line N3 is obtained by connecting P3 and P4.
The normal of N3 at the midpoint M2 between P3 and P4 is N4. The intersection of N3 and N4 at this time is the center 20c of the work 20 to be obtained. At this point, the detection of the positional deviation may be terminated, but the above-described analysis is performed for several orders over the entire circumference of the work 20 and the obtained values are averaged to perform detection with higher accuracy. It is desirable to do so.

According to the articulated robot 1 of the present invention configured as described above, it is possible to simultaneously perform the detection of the work position deviation amount and the movement of the work by the moving unit 2 when the work 20 is installed on the installation unit 8. It becomes possible. That is, the work 20
Orientation function to rotate (or use this data result to detect the displacement of the work center 20c)
And the movement of the first moving section 2 for moving the work 20 are formed so as to be independent of each other and to be able to proceed simultaneously, so that the work 20 is directed toward the process device 6 while being oriented on a robot. Can be moved. Therefore, there is no need to go through the conventional aligner position, and the articulated robot 1 can move the work 20 from the cassette 5 to the process device 6 in the shortest path. In addition, since the aligner 7 is integrally formed with the articulated robot 1, a space for installing the aligner as in the related art is not required, and the space can be effectively used by the space. In addition, since the articulated robot 1 and the aligner 7 are integrated, there is no need to perform a position adjustment operation when the aligner 7 is replaced.

The above embodiment is an example of a preferred embodiment of the present invention, but the present invention is not limited to this, and various modifications can be made without departing from the spirit of the present invention. For example, the first moving unit 2 in the present embodiment is configured by the slide moving unit 21, for example, as shown in FIGS.
As shown in FIG. 1, the first moving unit 2 including the turntable 22 may be used. Such a first moving unit 2
Has the same function as the arm in that the work 20 is moved by rotating, and also has a role as a base supporting the second moving unit 3 and the installation unit 8. In the embodiment shown in this figure, the above-described second arm 31, third arm 32, and hand unit 4 are connected to the rotary table 22 constituting the first moving unit 2 by the joint units 23, 24, and 34.
To form a moving unit.
In the articulated robot 1 in this case, the moving operation and the orientation of the work 20 can be performed simultaneously to reduce the time required for moving the work, as in the above-described embodiment. Further, by providing the slide moving unit 21 and the rotary table 22 in combination, the first moving unit 2 that can perform both the slide movement and the rotation may be formed.

[0023]

As is clear from the above description, in the articulated robot according to the first aspect of the present invention, the moving part constituting the articulated robot has a work installation part and a sensor part for detecting a positional deviation of the work. Is provided so that the detection by the sensor unit and the movement by the moving unit can be performed in a state where the work is installed on the installation unit of the moving unit, so that the work movement and the work position deviation detection are independent of each other. Can be done simultaneously. Accordingly, the work can be moved while detecting the positional deviation amount of the work, and the time required to move the work from the cassette to the process device is reduced. In addition, since the work setting section and the sensor section are provided on the articulated robot, the space can be effectively used as compared with a case where these are separately provided, and adjustment work at the time of replacement is not required. .

Further, in the articulated robot according to the second aspect of the invention, the installation section has a rotating means for rotating the installed work, and the sensor section is a sensor for detecting an end position of the work. Accordingly, the amount of positional deviation can be detected while rotating the work installed on the installation unit by the rotating means, and the work can be aligned so as to face a predetermined direction.

Further, in the articulated robot according to the third aspect of the present invention, the second moving section is constituted by the second arm and the third arm connected to the second arm, and the installation section and the sensor section are constituted by the first moving section. Alternatively, since the second arm, the second arm, the third arm, and the three nodes of the hand unit, which are provided from the first moving unit, are appropriately rotated, the work is properly held, or the work is set on the installation unit. Can be installed correctly.

In the articulated robot according to a fourth aspect of the present invention, the first moving unit is a slide moving unit, and the second arm, the third arm, and the hand unit are rotatably connected to the slide moving unit by the joint. Therefore, the second arm and the like can be rotated with respect to the slide moving unit even while the slide moving unit is moving. Therefore, while the work is moved by the slide moving unit, the work can be set on the setting unit or held by the second arm or the like, thereby moving the work from the cassette to the process device. Can be shortened.

Further, in the articulated robot according to the fifth aspect, the first moving section is a rotary table, and the second arm, the third arm, and the hand section are rotatably connected to the rotary table by the joint section. Therefore, the second arm and the like can be rotated with respect to the rotary table while the rotary table is rotating. Therefore, while the work is moved by the rotary table, the work can be installed on the installation section or held by the second arm or the like, thereby making it possible to move the work from the cassette to the process device. The time required can be reduced.

[Brief description of the drawings]

FIG. 1 is a plan view illustrating an embodiment of an articulated robot according to the present invention.

FIG. 2 is a perspective view showing an aligner that constitutes a work position deviation detecting unit.

FIG. 3 is a diagram illustrating an output of optical measurement by a line CCD.

FIG. 4 is an enlarged view of the inside of the circle in FIG. 3;

FIG. 5 is a diagram simply showing a calculation process when performing a workpiece orientation.

FIG. 6 is a diagram showing a mechanism for detecting the center of a work.

FIG. 7 is a plan view showing another embodiment of the articulated robot of the present invention.

FIG. 8 is a side view showing another embodiment of the articulated robot of the present invention.

FIG. 9 is a plan view showing a conventional articulated robot, in which a process of taking out a work from a cassette and moving it to a process device via an aligner is shown in order from (A) to (F).

FIG. 10 is a plan view showing how a conventional articulated robot moves a work.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Articulated robot 2 1st moving part 3 2nd moving part 4 Hand part 8 Installation part 10 Sensor part 13 Work position deviation detection means 20 Work 21 Slide moving part 22 Rotary table 23 Joint part 24 Joint part 31 Second arm 32 3rd arm 34 joint

Claims (5)

[Claims] 1. A first moving part is connected to a second moving part via a joint part.
The moving part is movably held, and the work is set on the work displacement detecting means by a hand provided at the tip of the second moving part, and the work displacement is detected by the work displacement detecting means. In the articulated robot configured to detect, the moving unit constituting the articulated robot is provided with an installation unit for the work and a sensor unit for detecting a displacement of the work, and the installation unit for the moving unit is provided. A multi-joint robot configured so that detection by the sensor unit and movement by the moving unit are possible in a state where the robot is installed in the robot. 2. The apparatus according to claim 1, wherein the installation section has a rotation unit for rotating the installed work, and the sensor section is a sensor for detecting an end position of the work. Articulated robot. 3. The method according to claim 2, wherein the second moving unit includes a second arm and the second arm.
3. The articulated robot according to claim 1, wherein the articulated robot is configured by a third arm connected to the arm, and the installation unit and the sensor unit are provided on the first moving unit or the second arm. 4. 4. The first moving unit is a slide moving unit, and the second moving unit includes a second arm, a third arm,
4. The articulated robot according to claim 3, wherein the hand unit is rotatably connected to the joint unit. 5. The first moving unit is a rotary table,
4. The articulated robot according to claim 3, wherein the second arm, the third arm, and the hand unit are rotatably connected to the rotary table by joints.