JPH07267160A - Part mounting device - Google Patents

Abstract

PURPOSE:To prevent the occurrence of interference between the servo system of a supporting unit and a robot control system by a method wherein an encoder is arranged at the supporting unit or the robot, and a function is provided to transmit an output, in which the output of the encoder is reflected, to the other and control by following the other by means of the output. CONSTITUTION:A part hold hand 2 supported by a robot 1 is supported in the vicinity of a part mounting position by a different support unit 26. An output in which the output of an encoder mounted on the supporting unit 26 or the robot 1 is reflected is transmitted to the other 1 or 26 and the other 1 or 26 is caused to follow for control by means of the output. This constitution prevents the occurrence of interference between the surveo system of the supporting unit 26 and the control system of the robot 1 and performs high- precise positioning of a work.

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 for supporting a component holding hand supported by a robot by another support unit near a component mounting position, such as a vehicle door mounting device. It relates to the control device.

[0002]

2. Description of the Related Art FIG. 11 shows an outline of a door assembly line using a conventional door assembly device.

The illustrated door assembling apparatus is a 6-axis robot 1.
And a door holding jig 4 and a hinge pin inserting jig 6 attached to the robot 1, the door holding jig 4 and the hinge pin inserting jig 6 are configured separately, and the door holding jig 4 is always a robot. The hinge pin insertion jig 6 is attached to and detached from the door holding jig 4 each time the door 8 is attached to the body 10.

Further, the door assembling apparatus is arranged at the door assembling station 12, and the body 10 is intermittently fed into the door assembling station 12 by the body conveying line 14 and the door conveying line 16 is provided.
The door 8 is carried in by intermittent feeding by this, and the hinge pin insertion jig circulation line 18 is arranged in the door assembly station 12, and the hinge pin insertion jig 6 is moved by the circulation line 18 via the jig mounting table 20. A jig pin (not shown) is circulated between the jig passing position 22 and the tweezers position 24, and a hinge pin (not shown) is set on the hinge pin inserting jig 6 manually or automatically at the tweezers position. The tool 6 is moved to the jig transfer position 2 by the circulation line 18.
2 to the door holding jig 4, and at the jig passing position 22, the empty hinge pin inserting jig 6 having no hinge pin after the hinge pin is inserted is received from the door holding jig 4, and is received. Above tweezers position 2
4 to set the hinge pin at the tweezer position 24.

[0005]

By the way, like the above door assembling apparatus for a vehicle, the component holding hand 2 of the robot 1 simply grips the door 8 and brings it to the body assembling position, and the body side hinge hole. In the case where the door is attached to the door through the pin on the door side, the door 8 is generally heavy and the moving speed of the component holding hand 2 swinging between A and B is set to a high speed. Overhang including parts holding hands occurs. That is, a shake (elastic deformation) of 10 to 15 cm occurs at the tip of the robot component holding hand. For this reason, the reliability when passing through a narrow space is lost, and the body may be damaged.

Therefore, as a prior application, the applicant of the present invention, as shown in FIGS. 9 and 10, has an X-axis motor 3 composed of a servo motor, slightly before the door mounting position on the body 10.
The positioning jig 26, which is a movable table equipped with the 5, Y-axis motor 45 and is movable in the X and Y planes, is arranged, while under the robot's component holding hand 2, more precisely, the robot's grip 3
The fitting pin 28 is provided under the robot hand, and the pin 28 at the lower end of the robot hand is fitted into the positioning jig 26, and then the positioning jig 26 and the robot component holding hand 2 are held while maintaining the fitted state. It is proposed that the door 8 is moved to the door assembling position by synchronously moving together.

The above-mentioned structure is adopted because the amount of overhang and the amount of backlash are physical quantities that cannot be grasped by the encoder. In this regard, in conventional robot control, a method such as using a laser sensor to check the amount of displacement in space is used, and the robot itself is corrected by the detected amount of displacement, or the amount of overhang during teaching is foreseen. The method of teaching a little more experience value is adopted.

However, after depositing the door in the positioning jig 26, the positioning jig 26 and the robot component holding hand 2 must be moved together to the door mounting position in synchronization, so that the robot control system can be repaired. Prepare a tool servo system,
In both cases, the control is such that a vector having the same size and direction is simultaneously created. For this reason, if the control of both is not appropriate, the control of both control systems interferes with each other during the transportation of the door to the mounting position, which makes it impossible to position the workpiece with high accuracy or the servo motor is burnt out. Cause such a situation.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to solve the above problems and to grasp a physical quantity such as an overhang or a backlash which cannot be usually grasped by an encoder, and to detect a servo system of a support unit such as the above positioning jig. It is an object of the present invention to provide a component mounting device that eliminates the interference between the robot control system and a robot control system and enables highly accurate positioning of a work.

[0010]

In order to achieve the above object, the present invention provides a component mounting apparatus for supporting a component holding hand supported by a robot by another support unit near a component mounting position, The support unit or the robot is provided with an encoder, and an output that reflects the output of the encoder is transmitted to the other, and the output is followed to control the other to control it (claim 1).

In this component mounting device, the encoder may be provided on the support unit side (claim 2) or the encoder may be provided on the robot side (claim 1).

[0012]

[Function] Since the output reflecting the encoder output is transmitted from one of the support unit or the robot to the other and the other is followed and controlled by this output, interference between the control systems is eliminated and highly accurate workpiece positioning is possible. it can.

This is because, for example, when the port unit side is a 2-axis jig servo system and the robot side is a 6-axis servo system, it is possible to perform control that cannot be performed by a simple 8-axis robot. Distinguished from control. Therefore, the type of robot does not matter in the present invention.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the accompanying drawings.

6 to 8 show the mechanical construction of a door assembling apparatus for assembling a vehicle door to a body by a robot. Basically, it is the same as that already described with reference to FIGS. 9 to 11, and the same components are designated by the same reference numerals. However, in the door assembly apparatus of FIGS. 6 to 8, the grip portion 3 of the robot, which is the clamp unit, has the fingers 3a and 3b above and below it.
Is configured to be opened and closed by a cylinder 3c.
Two fitting pins 28 are provided on the lower surface of b. In addition, a positioning jig (support unit) 26, which is an X, Y moving table as a vibration and elastic deformation preventing device, is provided with two fitting holes 27 corresponding to this. The positioning jig 26 is moved in the X and Y planes by the X axis motor 35 and the Y axis motor 45. Reference numeral 29 is a control panel equipped with the following control system.

In FIG. 1 and FIG. 2, the upper side is the system component of the jig servo system 30, and the lower side is the robot servo system 50. As shown in FIG. 5, the vectors of the X, Y jig servo system 30 and the robot servo system 50 are set so that their directions and magnitudes are the same.

The jig servo system 30 side has a positioning jig 26.
Each of the two axes (X and Y axes) is controlled, and the portion indicated by block 31 controls the movement of point A (workpiece fixing point by the jig) in FIG. That is,
For X axis, axis controller 32, servo amplifier 3
4, X-axis motor 35 (MX), encoder 36 (EX)
X is equipped with a feedback control system composed of
The output of the encoder 36 provided in the shaft motor 35 is fed back to the shaft controller 32 as a feedback signal SX. Regarding the Y-axis, a feedback control system including an axis controller 42, a servo amplifier 44, a Y-axis motor 45 (MY), and an encoder 46 (EY) is provided, and the encoder 46 provided in the Y-axis motor 45 is provided. Is output to the axis controller 42 as a feedback signal SY. The block 31 controls the movement of the workpiece fixing point A (FIG. 4) by the jig.

For the axis controllers 32 and 42 of the "jig servo system 30", as shown in FIG.
Slave control systems 33 and 43 (black coating in the figure) are provided to add a function of sending the feedback signals SXF and SYF after adding the feedback signals EX and EY.

Next, on the robot servo system 50 side, similarly, for each of the normal 4 to 6 axes constituting the robot 1, in the present embodiment, each of the 6 axes, each axis controller 53, servo amplifier 54, and servo as shown in the drawing. Motor 56 (M1 to M
6) and a feedback control system composed of encoders 58 (E1 to E6) are provided, and the output of the encoder 58 provided in each axis motor 56 is fed back to the axis controller 53 as a feedback signal F. The overall control system 51 controls the movement of point B (workpiece fixing point by the robot) in FIG.

A master / slave control system 52 (black coating in the figure) is provided for the "robot servo system 50" to receive feedback signals SXF and SYF from the jig servo system 30. The function to follow is added.

4 and 5 are diagrams for explaining the operation, and the meanings of the symbols in the drawings are as follows. MX: X-direction traveling motor MY: Y-direction vertical movement motor A: Work piece fixing point by jig B: Work piece fixing point by robot (XA, YA, ZA): A point coordinate VA: A point movement vector (XB, YB , ZB): B point coordinate VB: B point movement vector ......: Workpiece As described above, the vector vectors of the X, Y jig servo system 30 and the robot servo system 50 are both as shown in FIG. The directions and sizes are set to be the same.

FIG. 3 is a flow chart when the door 8 is stored in the positioning jig 26. Until the door 8 is stored in the positioning jig 26, the control by the robot servo system 50 is the main, and from the stored state, the control by the jig servo system 30 is the main. By doing so, the overhang amount including the robot 1 and the component holding hand 2 is ignored.

In FIG. 3, first, the jig servo system 30 controls x and y to perform jig operation (steps S1 and S4). On the other hand, coordinate conversion to an absolute coordinate system is performed, and the result of feedback control is sent out as feedback signals SXF and SYF, and the robot servo system 5
0 is received, and each physical quantity is transmitted from the servo of the jig servo system 30 to the servo of the robot servo system 50 (steps S2 to S5).

In the robot servo system 50, after receiving the feedback signals SXF and SYF, the vector V of the jig servo system is received.
The difference between A and own vector VB (vector Vε) is calculated, the own movement vector S7 is corrected by Vε, and the robot is operated (steps S52 to S8). Thus, the robot servo system 50 follows the parts of the jig servo system 30.

In short, two servo systems of X and Y, and
If there is a robot system that controls it, the control is completely included in the overhang amount of the robot and the component holding hand, so this is completely separated and another servo system controls it. Therefore, the calculation circuit is used to perform the subtraction, and the normal servo feedback loop is rotated to obtain the displacement amount of both. The feedback value is mainly the amount of displacement on the jig servo system side when the door is left in the positioning jig. For that difference,
Make the robot servo system follow. In this way, by dynamically rotating the servo system with respect to the two systems, the two device parts are simultaneously moved.

In the above embodiment, in addition to the robot control system, another jig servo system having an encoder is provided.
Positioning up to depositing in the positioning jig 26 is the work of the robot side, and up to the place where the door is fitted to the body is the work of the biaxial jig servo system. According to this, since the robot servo system 50 flexibly follows the parts of the jig servo system 30, it is possible to obtain a high mounting position accuracy of the parts.

In the embodiment, the output reflecting the output of the encoder obtained by the support unit is transmitted to the other robot servo system to follow and control, but the output of the encoder obtained by the robot servo system is reflected. Output
It can also be sent to the servo system of the support unit for follow-up control. In this case, an encoder is provided on each axis on the robot side or a selected axis.

[0028]

In summary, according to the present invention, interference between control systems can be eliminated and workpiece positioning can be performed with high accuracy.

[Brief description of drawings]

FIG. 1 is a block diagram showing a control device according to an embodiment of a component mounting device of the present invention.

FIG. 2 is a diagram showing a master-slave relationship between a jig servo system and a robot servo system.

FIG. 3 is a diagram showing a part of a control flow of the control device of FIG.

FIG. 4 is a diagram for explaining a control operation of the present invention.

FIG. 5 is a diagram for explaining the control operation of the present invention.

FIG. 6 is a side view showing a component mounting device according to an embodiment of the present invention.

FIG. 7 is a front view showing a component mounting device according to an embodiment of the present invention.

FIG. 8 is a plan view showing a component mounting device according to an embodiment of the present invention.

FIG. 9 is a perspective view showing a component mounting device according to another embodiment of the present invention.

FIG. 10 is a top view showing a component mounting device according to another embodiment of the present invention.

FIG. 11 shows an outline of a door assembly line using a conventional door assembly device.

[Explanation of symbols]

 1 Robot 2 Robot Parts Holding Hand 3 Robot Grip 3a, 3b Finger 3c Cylinder 4 Door Holding Jig 6 Hinge Pin Inserting Jig 8 Door 10 Body 12 Door Assembly Station 14 Body Transfer Line 16 Door Transfer Line 18 Hinge Pin Insertion Fix Tool circulation line 20 Jig mounting table 22 Jig transfer position 24 Tweezer position 26 Positioning jig (support unit) 27 Fitting hole 28 Fitting pin 29 Control panel 31 Block 32 Axis controller 33 Master / slave control system 34 Servo amplifier 35 X-axis motor 36 Encoder 42 Axis controller 43 Master / slave control system 44 Servo amplifier 45 Y-axis motor 46 Encoder 50 Robot servo system 51 Overall control system 52 Master / slave controller System 53 Axis controller 54 Servo amplifier 56 Servo motor 58 Encoder

Claims (3)

[Claims] 1. A component mounting device in which a component holding hand supported by a robot is supported by another support unit near a component mounting position, and an encoder is provided in the support unit or the robot, and the output of this encoder is reflected. A component mounting device having a function of transmitting the output to the other and controlling the other by following the output. 2. The component mounting device according to claim 1,
A component mounting device characterized in that the encoder is provided on the support unit side. 3. The component mounting device according to claim 1,
A component mounting device characterized in that an encoder is provided on the robot side.