JP2565096Y2 - Laser marking device - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laser marking device which irradiates a target object with a laser beam and draws figures such as characters and symbols on the target object.

[0002]

_2. Description of the Related Art A laser marking apparatus includes, for example, a CO ₂ laser as a laser source, and irradiates a laser beam from the CO ₂ laser onto a surface of an object through a scanner constituted by a galvanometer mirror or the like. By drawing a figure on the surface of an object by controlling the deflection operation of the computer. For example, as shown in FIG. 1, an object (81) conveyed by a carrier (41) such as a belt conveyor.
When a predetermined figure is drawn on a target, in the conventional laser marking apparatus, the target (81) is placed on the marking head (8).
0), the carriage (41) is stopped, and the laser beam is irradiated on the surface of the stationary object (81) by irradiating the laser beam from the marking head (80) with X. It scans in the axis and Y-axis directions.

[0003]

However, in the conventional laser marking apparatus, since the object must be stationary during drawing of the figure, a plurality of objects conveyed by the carrier (41) as shown in FIG. Object (8
In the case of continuously drawing a figure in 1), the carrier 41 must be stopped every time the figure is drawn, and there has been a problem of poor production efficiency. SUMMARY OF THE INVENTION It is an object of the present invention to provide a laser marking device capable of accurately drawing a graphic element on an object while moving the object.

[0004]

A laser marking device according to the present invention comprises a laser source, an optical scanning system for deflecting laser light from the laser source in a two-dimensional direction, and a control system for controlling the operation of the optical scanning system. And the displacement information of the moving object
Means for inputting sequentially . The control system, the sequential input
Based on the force has been the displacement information, data coordinate correction means for correcting the direction of the position change is provided for the position change amount corresponding laser beam marking of the object, corrected coordinates obtained from said coordinate correction means Data is provided to the optical scanning system.

[0005]

In the above laser marking apparatus, the scanning by the laser beam is performed without stopping the movement of the object. In this process, displacement information indicating a change in the position of the object is input to the control system every moment. On the other hand, the coordinate data obtained from the coordinate generating means represents the coordinates of the laser beam irradiation position on the stationary object. In the operation of the optical scanning system, for example, when laser light is to be scanned in the X-axis direction (or Y-direction) in accordance with the coordinate data from the coordinate generating means, the X-axis direction (or Y-direction) of the target object The X-axis coordinate value of the laser beam irradiation position (or Y
(Axis coordinate values) are corrected, and the coordinate conversion is performed from the relative coordinates on the object to the absolute coordinates including the moving plane of the object. According to the coordinate data on the absolute coordinates (corrected coordinate data), accurate drawing is performed even on a moving object.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the drawings. As shown in FIG. 1, an object (81) is placed on a carrier (41) and transported in one direction. The transport speed is, for example, 40 m / min. A position detector (42) composed of a rotary encoder or the like is attached to the carrier (41), and detects the moving distance of the target (81). The position detector (42) emits an encoder pulse P according to the moving distance of the carrier (41) as shown in FIG.

A marking head (80) incorporating a CO ₂ laser beam and an optical scanning system is attached above a carrier (41) via a support arm (43). ) Facing the surface. The marking head (80) is connected to a controller (40) to be described later, and controls the ON / OFF operation of the CO ₂ laser and the deflection operation of the optical scanning system. The laser scanning speed of the marking head (80) is, for example, 3000 mm / sec.
c. The position detection signal obtained from the position detector (42) is sent to the controller (40), and is used for controlling the optical scanning system by the controller (40).

FIG. 3 shows an internal configuration of the controller (40). The ROM (2) and the RAM (3) are connected to an address bus and a data bus of the CPU (1), and a graphic drawing is performed. GDC which is LSI
(Graphic display controller) (4) is connected. As the GDC (4), for example, “μPC72123” manufactured by NEC can be used.

The ROM (2) stores graphic data for each of a plurality of line elements constituting various graphics. In the figure data, the line type of the line element (straight line, ellipse, etc.)
And the coordinates of the start and end points of the line element, and in the case of an ellipse, the center coordinates and the lengths of the long axis and short axis are stored. Further, the graphic data includes laser ON / OFF basic data for turning on the laser at the start point of the line element and turning off the laser at the end point.

The CPU (1) executes a computer program registered in the ROM (2) to create a graphic drawing command including the graphic data, and stores the command in G
Supply to DC (4). GDC (4) is CPU (1)
Receives a command for one line element from
Based on the command, a set of a large number of coordinate data representing a locus connecting the start point and the end point of the line element is calculated. Laser ON / OFF data corresponding to the start point and the end point of the trajectory is calculated based on the laser ON / OFF basic data. The data output speed of the GDC (4) is, for example, when one straight line is drawn, the output time of one coordinate is 0.2 μs, and the operation of an X-axis scanner (8) and a Y-axis scanner (9) described later. Speed (at least 5.0 μs per coordinate)
It is much faster than.

The coordinate data and the laser ON / OFF data calculated by the GDC (4) are sent to the FIFO memory (5) through the graphic address bus GA and the graphic data bus GD, respectively. The FIFO memory (5) has a capacity capable of storing, for example, 64 pieces of coordinate data on a locus, data is stored in order at each address, and the stored data is sequentially read out at a constant speed.

Among the data output from the FIFO memory (5) at a constant speed, the coordinate data Ax in the X-axis direction is supplied to the first input terminal of the X adder (50), and the coordinate data A in the Y-axis direction is inputted.
y is input to a first input terminal of a Y adder (51).
The laser ON / OFF output from the FIFO memory (5)
The OFF data D is sent to the laser control circuit (13), and a control signal for ON / OFF control of the CO ₂ laser (14) is created.

On the other hand, the encoder pulse P from the position detector (42) is given to each timing signal input terminal of the latch circuit (20) and the reset signal generating circuit (44).
A reference clock circuit (22) is connected to a data input port of the latch circuit (20) via a counter (21). The reset signal RE is input to the counter (21) from the reset signal generation circuit (44). The counter (21) counts the clock CLK from the reference clock circuit (22) generated within the cycle T as shown in FIG. 2B while being reset every cycle T of the encoder pulse P by the reset signal RE. The count value is output to the latch circuit (20). When a data read command is issued from the CPU (1) to the latch circuit (20) via the address bus, the data latched by the latch circuit (20) is read by the CPU (1) via the data bus. Become. In response, the CPU (1) calculates position correction data Bx in the X-axis direction and position correction data By in the Y-axis direction. The calculation process at this time will be described later.

The data bus of the CPU (1) has a latch X (10) for latching the position correction data Bx in the X-axis direction and a latch Y for latching the position correction data By in the Y-axis direction. (11) is connected, and each output terminal is connected to each second input terminal of the X adder (50) and the Y adder (51). Output terminals of the X adder (50) and the Y adder (51) are connected to an X-axis scanner (8) and a Y-axis scanner (9) via D / A converters (6) and (7), respectively. .

The operation of the laser marking device when the object (81) is conveyed in the X-axis direction by the carrier (41) as shown in FIG. 1 will be described below. The position detector (42) is provided in accordance with the moving distance of the carriage (41) as shown in FIG.
(A) The encoder pulse P shown in FIG.
Is sent to the reset signal generation circuit (44), and the counter (21) is reset. The counter (21) starts counting the clock CLK from the reference clock circuit (22) at the same time as the reset. When the next encoder pulse P is generated, the pulse P is sent to the latch circuit (20), so that the counter (2)
The count value of 1) is latched by the latch circuit (20). Thereafter, the CPU (1) sends the latch circuit (2
By accessing (0), the count value is taken into the CPU (1). In response, the CPU
(1) calculates the period T by converting the count value into time.

Further, the CPU (1) calculates position correction data Bx in the X-axis direction and position correction data By in the Y-axis direction based on the value of the cycle T. In the case of the embodiment, since the carriage (41) moves in the X-axis direction,
The position correction data By is zero. Here, the distance that the object (81) moves within one cycle T of the encoder pulse P is d, the unit distance of scanning by the X-axis scanner (8), that is, the pitch of dots forming a figure (or a coordinate unit). Assuming that the corresponding length is b, the time c required for the object (81) to move by one dot pitch is represented by the following equation (1).

[0017]

C = b / (d / T) = (b / d) × T

Therefore, when the object (81) is moving in the positive direction of the X axis, position correction data Bx for increasing the coordinate data by one dot per time c is calculated, and the correction is performed. By operating the X-axis scanner (8) based on the corrected coordinate data obtained by adding the data to the original coordinate data, an accurate figure can be drawn on the moving object (81). In FIG. 3, after the position correction data Bx obtained from the CPU (1) is latched by the latch X (10), the timing is such that the coordinate data Ax is sent from the FIFO memory (5) to the X adder (50). , The position correction data Bx of the latch X (10) is added to the X adder (50).
Sent to As a result, the coordinate data Ax and the position correction data Bx are added by the X adder (50), and the corrected coordinate data Ax 'obtained thereby is sent to the X-axis scanner (8) via the D / A converter (6). Supplied.

When the object (81) is conveyed in the Y-axis direction by the carrier (41), position correction data By is calculated in the same manner, and corrected coordinate data obtained by adding the corrected data to the original coordinate data. , The Y-axis scanner (9) is operated. That is, in FIG.
The position correction data By obtained from (1) or the latch Y (1
After being latched in 1), the position correction data By of the latch Y (11) is changed to Y in accordance with the timing at which the coordinate data Ay is sent from the FIFO memory (5) to the Y adder (51).
It is sent to the adder (51). Then, the Y adder (5
In 1), the coordinate data Ay and the position correction data By are added, and the corrected coordinate data Ay 'obtained by this is added to D /
It is supplied to a Y-axis scanner (9) via an A converter (7).

For example, as shown in FIG. 4, when the surface of an object (81) moving at a constant speed in the X-axis direction is scanned in the order of →→→ to draw a rectangle, coordinate data Ax is expressed as
It changes in the X-axis direction as shown in FIG. here,
The position of the object (81) changes at a constant speed as shown in FIG. 5 (b), and the corrected coordinate data Ax 'shown in FIG. 5 (c) is calculated according to the change in the position, and the corrected coordinate data Ax' is calculated. , The scanning in the X-axis direction is performed. As a result, the rectangle in FIG. 4 is accurately drawn on the surface of the moving object (81).

[0021]

[0022]

The description of the above embodiments is for the purpose of explaining the present invention, and should not be construed as limiting the invention described in the claims for utility model registration or reducing the scope. Further, the configuration of each part of the present invention is not limited to the above-described embodiment, and it is needless to say that various modifications can be made within the technical scope described in the claims for utility model registration.

[0024]

According to the laser marking device of the present invention, since a graphic element can be accurately drawn on an object while moving the object, the marking can be performed continuously on a plurality of objects. , High production efficiency can be obtained. Also,
Input even when the moving speed of the object fluctuates
Since the data for drawing is corrected according to the displacement information,
Appropriate drawing can be performed regardless of movement.

[Brief description of the drawings]

FIG. 1 is a perspective view of the entire laser marking device.

FIG. 2 is a time chart of an encoder pulse and a clock.

FIG. 3 is a block diagram showing the inside of a controller.

FIG. 4 is a diagram illustrating a moving direction of an object and a scanning path of a scanner.

FIG. 5 is a graph showing a time change of coordinate data, a position of an object, and corrected coordinate data.

[Explanation of symbols]

 1 CPU 40 Controller 41 Carrier 42 Speed Detector 80 Marking Head 81 Target

Continuation of front page (56) References JP-A-59-45091 (JP, A) JP-A-5-169286 (JP, A)

Claims (2)

(57) [Scope of request for utility model registration] 1. A laser marking device which draws a figure such as a character or a symbol on the surface of a moving object by irradiating the surface of the moving object with the laser light and scanning the laser light in a two-dimensional direction. A laser source, an optical scanning system for deflecting laser light from the laser source in a two-dimensional direction, a control system for controlling the operation of the optical scanning system, and means for sequentially inputting displacement information of a moving object. comprising, in the control system, Exiled
Coordinate correction means for correcting data for drawing the laser beam in the direction of the position change by an amount corresponding to the position change of the target object based on the next input displacement information is provided, and obtained from the coordinate correction means. A laser marking device for supplying correction data to the optical scanning system. 2. A laser marking device which draws a figure such as a character or a symbol on the surface of a moving object by irradiating the surface of the moving object with the laser light and scanning the laser light in a two-dimensional direction. A laser source, an optical scanning system for deflecting laser light from the laser source in a two-dimensional direction, a control system for controlling the operation of the optical scanning system, and means for sequentially inputting displacement information of a moving object. The control system includes: coordinate generating means for generating coordinate data corresponding to a figure to be drawn; and, based on the sequentially input displacement information, changing the coordinate data by the position change of the target object in the direction of the position change. And a coordinate correcting means for performing correction, and supplying corrected coordinate data obtained from the coordinate correcting means to an optical scanning system.