JPS58155199A - Detector for position of material to be worked - 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 The present invention relates to a device for detecting the position of a workpiece transported by a transport device in a direction orthogonal to the transport direction.

When transporting a vehicle body (by a transport device) and performing mounting, welding, or sealing work on the vehicle body by a robot placed parallel to the transport device, the position is perpendicular to the transport direction of the unit and perpendicular to the transport direction. It is required to accurately detect the position in the direction in which the object is to be detected. By the way, when trying to detect the position of a car body in a direction perpendicular to the transport direction by contacting the car body, it is necessary to avoid causing damage such as scratches to the car body. Preferably, the contact action is performed automatically.

The present invention was made in view of the above-mentioned pupil point.

With that purpose, ζro automatically attaches to the workpiece without causing any damage to the workpiece! ! It is an object of the present invention to provide a position detection device for a workpiece that can detect the position of a workpiece in a direction perpendicular to the transport direction of the vehicle body by touching the vehicle body.

Next, a preferred example according to the present invention will be explained based on one aspect.

In the figure, brackets 2 and 3 are fixed to the support base IK.
Fi, a shaft 5 is rotatably provided via a bearing 4; one end of an arm 7 is rotatably attached to the shaft 5 via a bearing 6; A roller 8 made of Nirarethane rubber is attached to the tip of the arm 7 so as to be rotatable in the entry direction about the center line 9 of the arm 7. One end of the piston rod 13 of the air cylinder 12 is attached to the round shaft 10 attached to the arm 7 via a bearing 11.
- The cylinder body 14 of the cylinder 12 is rotatably attached to one end of the support member 16 via the shaft 15, and the other end of the support member 16 is attached to the cylinder body 14. 17 to the shaft 5.

One end of the fill spring 18 as a pulling member is attached to the shaft 10, and the springs 18, &.

The other end is attached to a bottle 19 planted in a bracket. A social gear 21 meshes with a gear 20 fixed to one end of a shaft 50.

The detector attached to the bracket 3 is a seven p-tary type encoder 220 fixed to the rotating wheel 23. In the stoppers 24 and 25 provided by bridging the brackets 2 and 3, the stopper 24 prevents the support member 16 from rotating more than a certain amount in the B direction about the axis 5, and the stopper 2S Prevents rotation beyond a certain amount in the opposite direction, that is, in the C direction. Defined by a piston 26 in the cylinder body 14 7v, in two tigers 27 and 28.

[27 is a one-way valve 29. Variable throttle passage 30 and solenoid valve 3
1 to the compressed air source 32 through the one-way valve 33. The compressed air source 32 is connected to a compressed air generation source 32 via a variable throttle passage 34 and a solenoid valve 31, respectively. The valve 31 is operated by a signal from the control device 35. The control device 3S is
9. having an up-down counter 36 receiving two electrical signals from the encoder 22 resulting from rotation of the shaft 23 in directions B and C; The counter 36 integrates a signal indicating the amount of rotation in the B direction supplied from the encoder 22 when the shaft 230B rotates, and uses this integrated value as the rotation amount in the C direction supplied from the encoder 22 when the shaft 23 rotates in the C direction. Subtract by the signal indicating the amount.

A vehicle body 37 as a workpiece is placed on a conveyor 39 running on rails 38 and conveyed in the D direction. car body 3
In order to detect the arrival at a predetermined position in the transport direction of 7, that is, in the D direction, a light emitting device 4 is provided facing downstream in the D direction.
An optical detector 42 consisting of 0 and a photoelectric converter 641 is provided, and a detection signal of the detector 42 is supplied to the control device 35. The nine-jointed robot body 44, which is placed on a moving device 43 so as to be moved in a direction parallel to the conveying direction of the vehicle body 37, that is, in the D direction and the E direction opposite thereto, is operated by a program taught and stored in advance. Using the data, the car body 37 is painted with scissors, for example.

The scissors 50 for detecting the position of the workpiece constructed in this way is arranged near the rail 38 in the spreading work area. vehicle body 3) by the device 50 in a direction perpendicular to the OD force direction;
That is, to explain the operation of detecting the position in the F direction, before the detection operation, the valve 31 is set to the position 11 shown in FIG. 5, the air cylinder 12 is most retracted, and the support member The arm 7 is urged by the 16#i spring 18 and comes into contact with the stopper 25, and the arm 7 is set at the position 9151. When the vehicle body 37 is transported in the direction D by the transport device 39 and the light of J emission @40 is blocked by the vehicle body 37, the photoelectric converter 41 no longer receives light, and as a result, the detector 4
2 supplies the control device 35 with a signal indicating the arrival of the vehicle body 37, and upon reception of this signal, the control device 35 and the source 32
The compressed air in the chamber 28 is supplied to the chamber 27 via the valve 31.29 and the restriction passage 30, while the compressed air in the chamber 28 is supplied to the restriction passage 3.
4 and valve 3"1 to be discharged to the outside via valve 3"1.
Set 1. ii! When compressed air is supplied to 27,
The rod 13aF protrudes in the direction L, and the rod 130F protrudes in the direction, so that only the arm 7, which is not recessed, moves B around the shaft 5.
rotated in the direction. When the center line 52 of the spring 18 passes through the center of the shaft 5 during the rotation of the arm 7 in the direction B, the spring 18 also generates a force that causes the arm 7 to rotate in the direction B. vertical line l1
When the arm 7 is rotated in the B direction beyond i153, a force that causes the arm 7 to rotate in the B direction is also generated due to the arm's own weight. When all the rods 13 are protruded from the cylinder body 14, the three pistons 26 and the cylinder body 14 come into contact with each other, so that the air cylinder rotates in the B direction due to the tension of the spring 18 and the arm 7's own weight. 12 and the support member 16 are also rotated in the crow's direction around the shaft 5! As a result of i1+, the 1-meter wheels 20 and 21 are rotated, and the encoder 22 generates a signal indicating the amount of rotation in the B direction, and this signal is counted by the counter 36. When the arm 7 is further rotated in the direction B, the roller 8 comes into contact with the front surface of the vehicle body 37, and as a result, zero rotation in the direction B of the arm 70B is prevented. After a predetermined period of time has passed since the reception of the vehicle body arrival signal from the detection valve 42, the control device 35 sets the solenoid valve 31 to the state shown in No. 5-.

The value accumulated by the counter 36, that is, the detected position of the vehicle body 37 in the F direction is supplied to the control device of the robot body 44. To this, compressed air from source 32 is supplied via valve 31.33 and passage 34, while 1jj12π0 compressed air is supplied to this.

Passage 30. It is discharged to the outside via the valve 31, and the μrad 13
It is moved in the #'iC direction and begins to move. As the rod 13 moves in the C direction, the arm 7 is rotated in the C direction about the shaft 5 with respect to the support member 16, and rotational torque in the C direction is applied to the arm 7 by the spring 18 and its own weight. The support member 16 is also rotated in the C direction and comes into contact with the stopper 25. As a result of the shaft 23 being rotated by the rotation of the support member 16 in the C direction, a signal for subtracting the accumulated content of the counter 36 is output from the encoder 22, and the stopper 25 of the support member 16 comes into contact with the counter 36. The content of becomes zero. Furthermore, since compressed air is supplied to 1i28, the 'pb' rad 13 is moved in the direction C, and the arm 7 is finally reset to position 51.

The robot main body 440 control device determines the difference between the detected position in the direction orthogonal to the B direction, that is, the F direction, supplied from the counter 36, and a preset reference position, and corrects the stored program data based on this difference. Add the main body 4
The operation of 0 or more for activating 4 is repeated each time a new vehicle body is transported one after another. The stopper 24 is moved past the arm 7 and the support member 16 when they are rotated in the B direction.

In order to prevent the arm 7 from being reset to the position 51 due to the movement of the rod 13DG, the support member 1
6 is prevented from rotating beyond a certain amount in the B direction.

Incidentally, if the vehicle body 37 is displaced by a certain amount or more in the direction FKM orthogonal to the direction B,

The tension of the nine coil springs 18 may be set to be extremely small to activate the alarm.
The roller 8 is practically pushed into the vehicle body 37 by the weight of the arm 7! You may also touch it.

As mentioned above, according to the present invention, the rounding allows the arm to contact the workpiece with extremely high force.

In addition, there is no risk of damaging the workpiece.

A large detection operation that allows the arm to rotate to a predetermined position using the F cylinder can be automatically and quickly performed. On top of that,
In the rotation of the arm O, the rotary encoder is rotated only within the necessary range for position detection, so that the position detection resolution can be increased, and the displacement of the workpiece can be detected with high accuracy.

[Brief explanation of drawings]

Fig. 1 is an explanatory diagram of a preferred example of the present invention applied to a car body painting line, Fig. 2 is a side view of the car body coating line of Fig. 1111, Fig. 3 is a side view of the detection device shown in Fig. 1, FIG. 4 is a detailed view of the detection device shown in FIG. 3, and FIG. 5 is an explanatory diagram of the operation of the detection device shown in FIG. 3. F...Arm, 12...Air cylinder. 18... Coils Fring. Agent Yoshimasa Kawaguchi

Claims (1)

[Claims] A device for detecting the position of a workpiece transported by a transport device in a direction perpendicular to the transport direction, comprising an arm rotatably supported on a base at one end; Detects an air cylinder whose other end is pivoted to the base, a pull member whose one end is attached to an arm, and the other end to the base, and the amount of rotation of the air cylinder with respect to the base. When the arm is rotated relative to a predetermined lid base due to the extension of the air cylinder, the air cylinder and arm are further rotated relative to the base in four directions, and the other end of the arm is rotated relative to the base. A device for detecting the position of a movable workpiece, which is configured to approach the workpiece.