JP2000263475A - Marking device by tracking conveyance - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a marking device by a tracking conveyance to dispense with alignment and a stop of works and perform marking as the work is conveyed. SOLUTION: Works 3 are placed on a conveyor 1 at intervals of a plurality of works and in a position and an attitude at random. Photographing is effected one time at preset intervals of a photographing distance (one pitch) by a camera 9. An arm robot 17 moves a printing part 15 to a position above the work 3 and following of the work 3 is started. A printing work is carried out with movement of a printing part 15 continued at the same speed as that of the conveyor 1. In this case, following of a movement speed is carried out by a signal of an encoder pulse.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a marking device using tracking transport, and more particularly to a marking device using tracking transport that can perform marking while transporting a workpiece without the need to align or stop the workpiece.

[0002]

2. Description of the Related Art A conventional marking device is a combination of a printing device by ink spraying or a printing device by dot printing by a laser device, a work transport device, and an alignment device for aligning a work to be printed. Be composed.

[0003] The work is aligned upstream of the transport device or while being transported, and is passed through the position of the printing device. At this time, printing is performed on the work by the printing device while passing the work or temporarily stopping the work.

[0004]

By the way, in the conventional marking device, the work to be printed has to be aligned, so that an aligning device such as a parts feeder is required, and the work which is difficult to align is manually performed. Alignment was taking place. Further, when the work is stopped at the printing position, a stop unit is required.

As described above, the aligning device, the stopping unit,
In addition, extra equipment and steps such as manual intervention are required, and the operation rate is reduced due to trouble of the equipment, and waste is caused in the transport efficiency and the work efficiency.

SUMMARY OF THE INVENTION The present invention has been made in view of such conventional problems, and an object of the present invention is to provide a marking device by tracking conveyance capable of performing marking while conveying a work without necessity of aligning and stopping the works. And

[0007]

SUMMARY OF THE INVENTION Accordingly, the present invention provides a transporting device driven by a motor, an encoder for detecting a moving distance of the transporting device, an interval, a position,
At least one work whose posture is randomly fed, a camera that images the work each time a movement distance detected by the encoder reaches a predetermined distance, an initial position of the work imaged by the camera, and / or Or image processing means for calculating the posture, a printing area which is set downstream of the feeding point of the work in the moving direction of the transfer device and is capable of marking the work, and a work area of the work calculated by the image processing means. Current position / posture calculating means for calculating the current position and / or posture of the work by adding the movement distance detected by the encoder to the initial position and / or posture; The current position and / or current position of the work calculated by the current position / posture calculation means while following the movement distance detected by the encoder. Based on the posture, an arm robot that performs at least one of rotation, horizontal movement, descent and ascent in a horizontal plane to perform marking on the work, and is disposed at an end of the arm robot, The apparatus includes a marker head that performs marking on the work, and a marking data processing unit that performs at least one of reading, editing, and saving of marking data to be applied to the work from the marker head.

[0008] The transport device is driven by a motor. The encoder can detect the moving distance of the transport device. The work is placed on at least one transfer device. This work is supplied at random with intervals, positions, and postures. The camera captures an image of the workpiece each time the moving distance detected by the encoder reaches a predetermined distance. The camera captures the entire image of the workpiece at least once within the field of view of the camera.

The predetermined distance is set such that the entire image of the work can be imaged at least once. For example, if the predetermined distance is too large within the range of the field of view of the camera, the entire work may not be imaged.

[0010] On the other hand, if the interval is too narrow, many images of the whole work are taken at short intervals within the field of view of the camera, which is wasteful. However, it is possible to use, for example, only the first one of the plurality of images.
It should be noted that the reason why the imaging is performed based on the moving distance detected by the encoder is to provide a temporal relationship with the subsequent marking processing.

[0011] The image processing means calculates the initial position and / or posture of the work imaged by the camera. The printing area is an area that is set downstream from the material supply point of the work in the moving direction of the transport device and is capable of marking the work.

The current position / posture calculating means calculates the initial position and / or posture of the work calculated by the image processing means.
The current position and / or posture of the work is calculated by adding the moving distance detected by the encoder.

When a work enters the printing area, the arm robot follows the movement distance detected by the encoder. Then, in order to perform marking on the work based on the current position and / or posture of the work calculated by the current position / posture calculation means, at least one of rotation, parallel movement, descent, and ascent in a horizontal plane is performed. Perform two actions.

The coordinate system includes a camera coordinate system to which the camera belongs and a robot coordinate system to which the arm robot belongs. The initial position and / or posture of the work and the current position and / or posture of the work are easily processed. In consideration of pod computation efficiency, data is converted into one virtual coordinate system in advance.

Whether a work has entered the print area is determined by
Judge from the current position of the work calculated by the current position / posture calculation means. For this reason, a special position detection sensor or the like is not required, so that the configuration can be made at a low cost.

The marker head is provided at an end of the arm robot and performs marking on a work. The marker head is capable of, for example, printing, printing, engraving, marking, and the like, and may be in contact with or not in contact with the work. The reason why the arm robot is lowered or raised is to prevent the marker head from colliding with the convex portion when marking the concave portion of the workpiece when the workpiece has irregularities.

The marking data processing means performs at least one of reading, editing, and saving of the marking data given to the work from the marker head. As the marking data, data created by another computer or the like may be read and used, or data edited by marking data processing means may be used. As described above, since there is no need for work alignment, an alignment device is unnecessary. In addition, the operation rate is not reduced by the trouble of the alignment device.

Further, since the arm robot performs marking in a form following the work, a work stop unit is not required. Further, a decrease in the operation rate due to the trouble of the stop unit is eliminated. The work efficiency is increased because the marking work is performed while being transported. Further, tooling (for example, a clamper or the like) due to a difference in workpiece shape is not required. Even when the workpiece is difficult to align, no manual intervention is required.

Further, the present invention provides the above-mentioned arm robot,
When the work enters the print area, based on the current position and / or posture of the work calculated by the current position / posture calculation means, the work moves to a start point of marking on the work, and the start point is set. As a criterion,
All the marking data stored by the marking data processing means is marked on the work at one time while following the moving distance detected by the encoder.

The arm robot moves to a start point of marking on the workpiece. Then, with the start point as a reference, all the marking data stored by the marking data processing means is marked on the workpiece at one time while following the moving distance detected by the encoder. Thereby, marking in the case of stamping or the like can be easily performed. All of the marking data refers to data that can be marked at a time by the marker head.

Further, according to the present invention, the marking data stored by the marking data processing means includes at least one of characters, graphics, symbols, patterns, images, and colors continuous in the row direction and / or the column direction. When the work enters the print area, the arm robot is based on a current position and / or posture of the work calculated by the current position / posture calculation means.
Move to the starting point of marking for the workpiece,
Aiming at the marking direction calculated from the posture while following the movement distance detected by the encoder from the start point, the marking data stored by the marking data processing unit is sequentially and continuously applied to the workpiece in the row direction or It is characterized by marking in the column direction.

The marking data is continuous data including at least one of continuous characters, figures, symbols, patterns, images, and colors. This marking data is
It may be continuous in the row direction or continuous in the column direction. Further, both directions may be continuous.

In this case, when the work enters the print area, the arm robot moves to the start point of the marking on the work based on the current position and / or posture of the work calculated by the current position / posture calculation means. . The marking direction is calculated from this posture. Then, the marking data is marked in the marking direction while following the moving distance detected by the encoder from the start point.

At this time, the marking is performed on the workpiece sequentially and continuously in the row direction or the column direction. That is,
After marking the plurality of dots in the row direction, the operation of moving the arm robot in the column direction and marking the plurality of dots in the row direction again is repeated. Alternatively, the marking may be repeated for each unit such as one character. From the above, the position and / or
Alternatively, continuous data can be easily marked on works having different postures.

[0025]

Embodiments of the present invention will be described below. FIG. 1 shows an overall external view of an embodiment of the present invention. In FIG. 1, a plurality of works 3 are randomly placed on a conveyor 1 at intervals, positions, and postures. The conveyor 1 is rotated by a motor 5.
The moving distance of the conveyor 1 is detected by an encoder pulse output from the encoder 7.

A camera 9 is arranged above the conveyor 1 so as to monitor a predetermined range on the conveyor 1. Lights 11 and 13 are provided to clarify the shadow of the work 3. The printing unit 15 is attached to the tip of the arm robot 17.

FIG. 2 is a simplified plan view of an embodiment of the present invention.
FIG. 3 shows a simplified front view of the embodiment of the present invention. FIG.
In FIG. 3 and FIG. 3, a print area 19 is an area where the work of printing on the work 3 is performed within a range where the arm robot 17 can operate.

Next, the positioning of the conveyor 1, the camera 9, and the arm robot 17, which are main components of the embodiment of the present invention, will be described. First, the moving distance of the conveyor 1 per encoder pulse is calculated by actual measurement. The predetermined position of the conveyor 1 is moved, and the moving distance of the conveyor 1 at that time and the positional relationship of the arm robot 17 when following the movement are corrected. Then, the moving distance of the arm robot 17 per pixel of the camera 9 is corrected.

Although there are a camera coordinate system to which the camera 9 belongs and a robot coordinate system to which the arm robot 17 belongs, global coordinates in which the moving direction of the conveyor 1 is made coincident with the X axis in consideration of ease of data processing and calculation efficiency. Define the system.
As described above, the positional relationship between the conveyor 1, the camera 9, and the arm robot 17 is determined in advance by calibration.

Next, the operation of the embodiment of the present invention will be described with reference to the flowcharts of FIGS. First, the image recognition task in FIG. 4 will be described. In step 0, an image recognition task is started. In step 1 (abbreviated as S1 in the figure; the same applies hereinafter), the motor 5 is driven to operate the conveyor 1.
As shown in FIG. 2, a plurality of works 3 are randomly placed on the conveyor 1 at intervals, positions, and postures. However, the surface to be printed is positioned upward.

In step 2, it is determined whether or not a predetermined imaging distance interval (1 pitch) has been reached. If the pitch has reached 1 pitch, the process proceeds to step 3, where an image is taken by the camera 9. For example, when a camera having a visual range of 400 mm is used, about 100 to 200 mm is defined as one pitch, and imaging is performed once for each pitch.

As described above, the imaging distance interval is set at least once in the visual field range so that the entire image of the work 3 can be imaged. Images cut off in the middle of the work 3 are discarded by image processing. Counting to one pitch is performed by an encoder pulse output from the encoder 7.

In step 4, only the whole image of the work 3 is detected first, and all the shapes of the work 3 detected in the field of view at subsequent pitches are discarded in order to simplify the image processing. I do.

In step 5, the inclination of the work 3 and the start point 21 for starting printing are stored and registered together with the coordinate values in the global coordinate system. The value of the registered data changes at any time depending on the amount of movement of the conveyor 1. If the stop button has not been pressed in step 6, step 2
And the process is repeated from the imaging by the camera 9. Step 6
If the stop button is pressed in step, the image recognition task ends in step S7.

Next, the robot operation task of FIG. 5 will be described. In step 10, a robot operation task is started. In step 11, it is determined whether there is data of the work 3 registered in step 5. If the data of the work 3 has been registered, the process proceeds to step 12 to start printing.

However, the arm robot 17 is waiting at a predetermined position upstream of the print area 19 until the work 3 completely enters the print area 19. The arm robot 17 waits upstream because the work 3 flows from the upstream.
In order to minimize the moving distance of the vehicle. If the data of the work 3 is not registered, the arm robot 17 keeps waiting.

In step 12, the printing unit 15 attached to the arm robot 17 is moved above the work 3 as shown in FIG. At this time, the printing unit 15 is rotated in a horizontal plane based on the inclination of the work 3 registered in step 5 and the start point 21 at which printing is started, and is moved in parallel to the start point 21 at which printing is started.

Next, at step 13, the arm robot 17
Starts following the work 3. And step 14
Then, the printing unit 15 is lowered as shown in FIG. In step 15, while moving from FIG. 6B to FIG. 6C, the printing operation is performed while continuing the movement at the same speed as the conveyor 1.

The movement speed is followed by an encoder pulse signal. Then, in step 16, the printing unit 15 is raised as shown in FIG. In step 17, the arm robot 17 ends following the work 3.

As shown in FIG. 7, when the printing on the work 3 is, for example, one character, the arm robot 17 is moved while following the moving speed of the conveyor 1 and calculated based on the current position and posture of the work 3. It is possible to perform spot-like printing based on the start point 21 thus set. In this case, printing can be performed in a short time.

On the other hand, as shown in FIG. 8, when the printing on the work 3 is, for example, continuous data, the arm robot 17 is first moved to the start point 21 calculated based on the current position and posture of the work 3. . Further, a printing direction for printing continuous data can be calculated from this attitude.

From this start point 21, print data is printed in the print direction while following the movement distance detected by the encoder 7. In this case, continuous data can be easily printed even on the work 3 having different positions and postures.

In the case where there are a plurality of works 3, the printing operation is repeated by assigning a priority to the order in which the works 3 have entered the printing area 19. After one printing operation on the work 3 is completed, the work 3 may temporarily return to the standby state position, or may move to the current position and orientation of the next work 3 without returning, and may continue printing.

The lowering of the printing unit 15 in step 14 and the raising of the printing unit 15 in step 16 are caused, for example, when the work 3 has irregularities. This is to avoid damage.

If the stop button is pressed in step 18, the robot operation task ends in step 19.
If the stop button has not been pressed in step 18,
Returning to step 11, the operations from step 11 to step 17 are repeated as long as the work 3 exists.

[0046]

As described above, according to the present invention, based on the movement distance detected by the encoder, the marker head is marked on the work while following the current position and / or posture of the work. Therefore, there is no need to align or stop the work. For this reason, a work alignment device and a stop unit are not required, and the operation rate is not reduced due to troubles of the alignment device and the like at low cost. The work efficiency is increased because the marking work is performed while being transported.

[Brief description of the drawings]

FIG. 1 is an overall external view of an embodiment of the present invention.

FIG. 2 is a simplified plan view of an embodiment of the present invention.

FIG. 3 is a simplified front view of an embodiment of the present invention.

FIG. 4 is a flowchart illustrating an image recognition task.

FIG. 5 is a flowchart illustrating a robot operation task.

FIG. 6 is a diagram showing a printing operation.

FIG. 7 is a diagram showing a case where a work is printed in a spot manner.

FIG. 8 is a diagram showing a case where continuous data is printed on a workpiece.

[Explanation of symbols]

 1 Conveyor 3 Work 5 Motor 7 Encoder 9 Camera 15 Printing unit 17 Arm robot 19 Printing area 21 Start point

Claims (3)

[Claims] 1. A transfer device driven by a motor, an encoder for detecting a moving distance of the transfer device, at least one work whose interval, position, and posture are randomly supplied to the transfer device; A camera which takes an image every time the moving distance detected by the encoder reaches a predetermined distance, and an initial position and / or a position of the workpiece imaged by the camera.
Or image processing means for calculating the posture, a printing area which is set downstream of the feeding point of the work in the moving direction of the transfer device and is capable of marking the work, and a work area of the work calculated by the image processing means. Initial position and / or
Or a current position / posture calculating means for calculating a current position and / or posture of the work by adding a movement distance detected by the encoder to the posture, and when the work enters the print area, While following the movement distance detected by the encoder, based on the current position and / or posture of the work calculated by the current position / posture calculation means, rotation and translation in a horizontal plane for marking the work. , An arm robot that performs at least one of the descending and the ascending operations, a marker head that is disposed at an end of the arm robot, and performs marking on the work, and is provided to the work from the marker head. Marking data processing means for performing at least one of reading, editing and storage of the marking data; Marking device according to a tracking transport, characterized in that the. 2. The arm robot according to claim 1, wherein when the work enters the print area, the arm robot sets a mark on the work based on a current position and / or posture of the work calculated by the current position / posture calculation means. It moves to a start point, and marks all of the marking data stored by the marking data processing means on the work at one time while following the movement distance detected by the encoder with the start point as a reference. The marking device according to claim 1, wherein: 3. The marking data stored by the marking data processing means is continuous data including at least one of a character, a graphic, a symbol, a pattern, an image, and a color continuous in a row direction and / or a column direction. When the work enters the print area, the arm robot moves to a start point of marking on the work based on the current position and / or posture of the work calculated by the current position / posture calculation means. Then, while following the moving distance detected by the encoder from the start point, the marking data stored by the marking data processing means is sequentially and continuously performed on the workpiece in a marking direction calculated from the posture. 2. A marking by tracking transport according to claim 1, wherein the marking is performed in a direction or a row direction. Device.