JP3185660B2 - Marking method and 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 marking method and apparatus for marking characters, figures, and the like on the surface of a workpiece (hereinafter referred to as "work") with a laser beam.

[0002]

2. Description of the Related Art A method of irradiating a laser beam has conventionally been known as one of methods for marking characters, figures, and the like on a work. For example, a laser marking method is used to draw characters / graphics on a work, and the laser marking method is performed as follows. (1) A mask (stencil) inserted in the light is irradiated with laser light, and the work is marked by the laser light passing through the character / graphic pattern applied to the mask. (2) By controlling the movement of the beam irradiation position, a predetermined character /
A figure pattern is marked on a work.

The movement control of the laser beam in the method (2) is performed, for example, by using two sets of galvanometer scanners attached to a motor whose rotation angle is controllable (optical mirrors attached to a motor whose rotation angle is controllable). Using a scanner that scans the image. FIG. 7 is a diagram showing a schematic configuration of a marking device for marking a workpiece by the method (2) described above.
Is a laser that emits a laser beam, 2 is the galvanometer scanner described above, and 3 is a system controller.
In the figure, a laser beam emitted from a laser 1 is reflected by two sets of mirrors of a galvanometer scanner 2 and is irradiated onto a work W. The system controller 3 sends the galvanometer scanner 2 an X-direction position control signal Sx and a Y-direction position control signal Sy corresponding to the character / graphic pattern.
To control the angles of the two mirrors of the galvanometer scanner 2.

FIG. 8 is a view showing the arrangement of mirrors of the galvanometer scanner 2. As shown in the figure, two sets of X-axis mirrors 2a and Y-axis mirrors 2b whose rotation axes are orthogonal to each other are provided, and the X-axis mirror 2a and the Y-axis mirror 2b are controlled by an X-axis scanner 2c and a Y-axis scanner 2d. Driven. Laser light emitted from the laser 1 is reflected by the X-axis mirror 2a and the Y-axis mirror 2b, and a laser beam is applied to a predetermined position on the workpiece W.

FIG. 9 is a diagram showing an example of the configuration of the galvanometer scanner 2. Although the figure shows a circuit configuration for driving the X-axis mirror 2a, the circuit configuration for driving the Y-axis mirror 2b is also the same. As shown in the figure, a mirror driving unit 2e and a position sensor unit 2f are connected to the rotation axis of the X-axis mirror 2a, and the mirror driving unit 2e changes the X-axis mirror 2a in accordance with the driving current Ix output from the amplifier Amp1. To rotate. The rotation angle of the X-axis mirror 2a is detected by the sensor Sen of the position sensor 2f. The output of the sensor Sen is given to the amplifier Amp2,
The amplifier Amp2 outputs a position signal Px corresponding to the rotation angle of the X-axis mirror 2a. On the other hand, the amplifier Amp1 compares the irradiation position control signal Sx given from the control unit to be described later with the position signal Px, outputs a driving current Ix according to the difference, and drives the mirror driving unit 2e. Therefore, the X-axis mirror 2a is controlled to a rotation angle according to the position control signal Sx.

FIG. 10 is a block diagram showing the configuration of the system shown in FIGS. 7 to 9. That is, the system controller 3 includes the control unit 3a,
The control unit 3a outputs the irradiation position control signals Sx and Sy (Sy is a Y-axis position control signal) and controls the laser 1. The comparison unit 2g (corresponding to the amplifier Amp1) of the galvanometer scanner 2 outputs the position control signals Sx, S
y and the position signal Px output from the position sensor 2f.
, Py (Py is a Y-axis position signal), and outputs drive currents Ix, Iy to the mirror driver 2e. The mirror driving section 2e drives the X-axis mirror 2a and the Y-axis mirror 2b according to the driving currents Ix and Iy. X-axis mirror 2a, Y
The rotation angle of the axis mirror 2b is detected by the position sensor 2f and fed back to the comparator 2g. On the other hand, the laser beam emitted by the laser 1 is reflected by the X-axis mirror 2a and the Y-axis mirror 2b of the galvanometer scanner 2, and the work W
Is irradiated. When the work W is irradiated with the laser beam as described above and the work W is marked, the irradiation amount of the laser beam is determined according to the material of the work W.
Therefore, it is necessary to scan the laser beam at a constant speed according to the material of the work W, and it is necessary to move the X-axis mirror 2a and the Y-axis mirror 2b of the galvanometer scanner 2 at a constant speed. That is, the irradiation position control signals Sx and Sy output from the control unit 3a also need to be changed at a certain constant speed.

[0007]

By the way, when the character "Z" shown in FIG. 11 is marked in the order of → in the figure, the laser beam temporarily stops at each vertex of 〜 in the figure. Since the movable part of the galvanometer scanner 2 has inertia, the X-axis mirror 2 of the galvanometer scanner 2 is used when the movement is stopped or started as described above.
a, the Y-axis mirror 2b does not rotate at a constant speed. For this reason, the moving speed of the laser beam becomes slow in the vicinity of each of the above points.

FIG. 12 is a diagram showing the operation at the time of starting / stopping the movement of the laser beam and the trajectory of the mark marked on the work W. For example, regarding the X axis, when the position control signal Sx is output as shown in the figure, the actual movement of the beam is slightly delayed with respect to the position control signal Sx as shown in the figure, When stopped, the beam movement speed becomes slow. Therefore, in the vicinity of each of the above points, the irradiation amount of the laser beam increases, and the line width of the mark and the depth of the mark become non-uniform. That is, as shown in the figure, the trajectory of the mark marked on the workpiece W has a large width near the movement start / stop point of the laser beam. On the other hand, the gain of the amplifier Amp1 shown in FIG.
, Iy, the movement of the beam can quickly follow the position control signals Sx, Sy. However, the feedback control system becomes a vibration system and causes overshoot at the start / stop of the movement of the light beam. In particular, this tendency becomes remarkable when the moving speed of the light beam is high.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems of the prior art. It is an object of the present invention to provide a method for marking on a workpiece with a light beam, in the vicinity of a vertex of a character / figure. Line width,
An object of the present invention is to provide a marking method and apparatus capable of making the marking depth uniform.

[0010]

According to the present invention, the above-mentioned object is solved as follows. (1) Give a position control signal to the galvanometer scanner,
When the irradiation position of the light beam on the object to be processed is controlled by the galvanometer scanner and the light beam starts moving from the vertex of the character / graphic when marking the character / graphic on the object. Adding a first signal in a direction for increasing the scanning speed of the light beam to the position control signal for a predetermined period;
When reaching the vicinity of the vertex of the figure, a second signal in a direction for reducing the scanning speed of the light beam is added to the position control signal for a predetermined period. ( 2 ) Provide a position control signal to the galvanometer scanner,
The galvanometer scanner controls the irradiation position of the light beam on the object to be processed, and when marking a character / graphic on the object, the light beam moves from the top of the character / graphic according to the position control signal. After the scanning is started, the output of the light beam to be introduced into the galvanometer scanner is gradually increased in accordance with the acceleration until the scanning speed of the light beam reaches a predetermined speed. After reaching the vicinity of the vertex of the figure, until the scanning speed of the light beam is reduced and stopped, the output of the light beam introduced into the galvanometer scanner is gradually reduced in accordance with the deceleration. ( 3 ) giving a position control signal to the galvanometer scanner,
By the galvanometer scanner, on the workpiece
By controlling the irradiation position of the light beam, characters / figure
When marking the shape, etc., the light beam
/ When starting to move from the vertex of the figure,
Direction to increase the scanning speed of the light beam to the position control signal
The first signal is added and the light beam is
/ After starting the movement from the top of the figure,
Started introducing light beams to galvanometer scanners,
Also, the light beam reaches near the vertex of the character / graphic.
When the light beam travels to the position control signal for a predetermined period,
Add the second signal in the direction to reduce the inspection speed
A predetermined time for the light beam to reach the top of the character / figure.
Stop the light input to the galvanometer scanner before
You. ( 4 ) The above (1) and ( 2 ) are used in combination.

In the first and fifth aspects of the present invention, the scanning speed of the light beam in the vicinity of the vertex constituting the character / graphic is determined by the scanning speed of the position control signal. , And the line width and the marking depth of the mark in the vicinity of the vertex of the character / graphic can be made substantially constant. According to the second and sixth aspects of the present invention, as described in ( 2 ) above, the output of the light beam is gradually changed in the vicinity of the vertex of the character / graphic where the scanning speed of the light beam becomes slow. Therefore, even if the moving speed of the work becomes slow near the vertex of the character / graphic, the line width and the marking depth of the mark to be marked on the work can be made substantially constant. According to the third and fourth aspects of the present invention, the above ( 3) and (4)
As a result , more precise marking can be performed.

[0012]

FIG. 1 is a diagram showing a first embodiment of the present invention. 10, the same components as those shown in FIG. 10 are denoted by the same reference numerals, 1 is a laser, 2 is the galvanometer scanner described above, and 2
a and 2b are an X-axis mirror, a Y-axis mirror, 2e is a mirror drive unit, 2f is a position sensor unit, and 2g is a comparison unit.
Reference numeral 3 denotes the system controller described above, and 3a
Is a control unit. The control section 3a in the present embodiment includes a position signal generating means 31 for outputting position control signals Sx and Sy of the laser beam, and a start signal Spx added to the position control signals Sx and Sy when the movement of the laser beam starts / stops. ,
A start / stop signal generating means 32 for outputting Spy and stop signals Smx and Smy is provided.

FIG. 2 is a diagram showing the operation at the time of starting / stopping the movement of the laser beam, the trajectory of the mark marked on the work W, and the driving signal given to the galvanometer scanner 2 in this embodiment. Although the movement of the beam by the axis mirror is shown, the same operation is performed for the Y axis mirror. Next, a first embodiment of the present invention will be described with reference to FIGS. At the start of the movement of the beam, the start / stop signal generating means 32 of the control unit 3a shown in FIG. 1 outputs a start signal Spx (in this case, positive), and this start signal Spx is the position control signal S
x is output to the comparison unit 2g. For this reason, as shown in FIG. 2, the value of the position control signal given to the comparison unit 2g is Sx + Spx (= Sx '), and the deviation between the actual beam position and the value of the position control signal increases. 2
The drive current I output by g temporarily increases. As a result, a large driving force is applied to the mirror driving unit 2e of the galvanometer scanner 2, and the moving speed of the laser beam rapidly rises.

When the beam is stopped, the start / stop signal generating means 32 of the control unit 3a shown in FIG.
(In this case, negative), the stop signal Smx is added to the position control signal Sx, and the position control signal Sx 'is
Is output to For this reason, the value of the position control signal given to the comparing unit 2g is Sx + Smx (= Sx ': Smx <0), and the deviation between the actual beam position and the value of the position control signal becomes large, as shown in FIG. Meanwhile, the drive current I output from the comparison unit 2g temporarily increases to the negative side. As a result, a large deceleration force is applied to the mirror driving unit 2e of the galvanometer scanner 2, and the moving speed of the laser beam rapidly decreases immediately before stopping. Therefore, the period during which the moving speed of the laser beam at the start / stop of the movement is slower than in the case of FIG. 12 can be shortened, and the line width and the marking depth of the mark to be marked on the work are shown in FIG. As shown, it can be substantially constant.

FIG. 3 shows a position control signal Sx + Spx, Sx + Smx to which the movement of the beam and the start / stop signal given to the comparator 2g are added when the movement of the beam is repeated.
In this figure, the position control signal Sx is shown as a signal that changes continuously. As shown in the figure, start / stop signals Spx and Smx are added to the position control signal Sx when the beam starts and stops moving, and the beam quickly follows the position control signal Sx, and the moving speed of the laser beam is reduced. The period can be shortened. In this embodiment, as described above, at the time of starting and stopping the movement of the beam, the position control signals Sx and Sy include the start signals Spx and Sx, respectively.
Since Spy and the stop signals Smx and Smy are added, it is possible to shorten the period in which the beam moves slowly without the beam going too far, and to reduce the line width and the marking depth of the mark to be marked on the work. It can be constant.

FIG. 4 is a diagram showing the configuration of a system according to the second and third embodiments of the present invention. In FIG.
Are denoted by the same reference numerals, 1 is a laser, 2 is the galvanometer scanner described above, 2a and 2b are X-axis mirrors, Y-axis mirrors, 2e is a mirror driving unit, 2f Denotes a position sensor unit, and 2g denotes a comparison unit. Reference numeral 3 denotes the system controller described above, and reference numeral 3a denotes a control unit. Control unit 3a in the present embodiment
Is provided with a position signal generating means 31 for outputting position control signals Sx and Sy of the laser beam, and a laser control means 33 for controlling the laser 1.

FIG. 5 is a diagram showing the actual beam movement and the laser drive signal in the second embodiment of the present invention. Although FIG. 5 shows the beam movement by the X-axis mirror, the same applies to the Y-axis mirror. The same operation is performed. The operation of the second embodiment of the present invention will be described with reference to FIGS. At the start of the beam movement, the laser control means 33 outputs the position control signal Sx as shown in FIG.
After 00 to 700 μsec, the laser drive signal L is turned on.
Therefore, the laser 1 starts irradiation of the laser beam a predetermined time after the beam starts moving.

For this reason, when the moving speed of the beam is low, the laser beam is not irradiated onto the work, and the beam is irradiated onto the work after the beam speed becomes constant. As shown in FIG. The line width and the marking depth of the mark to be marked on the work can be made substantially constant. The predetermined time is a time from when the position control signal Sx is output from the control unit 3a to when the X-axis mirror 2a and the Y-axis mirror 2b of the galvanometer scanner 2 start rotating at a constant speed, and is specific to the galvanometer scanner. Take the value of Since the distance ΔX that the beam moves in the above-mentioned predetermined time is a minute value, the influence on the mark (figure) to be marked can be practically ignored during this time even if the laser beam is not emitted.

Also, a predetermined time before the stop of the movement of the beam, the laser control means 33 turns off the laser drive signal L and stops the emission of the laser beam from the laser 1 as described above. Thus, similarly to the above, when the beam moving speed immediately before the stop of the beam is low, the laser beam is not irradiated onto the work, and the line width and the marking depth of the mark marked on the work can be made substantially constant. . Only the first embodiment noted before <br/>, can not be the moving speed of the beam at the movement start / stop of the beam completely constant. Therefore, in conjunction with the present embodiment, in the first embodiment, the beam you turn on the laser 1 from the start of the movement after the predetermined time. As a result, more precise marking can be performed.

In the second embodiment, since the laser 1 is turned on a predetermined time after the beam starts moving, the length of the mark at the start / stop of the marking is equal to the distance ΔX as described above. , And a minute break occurs in the mark. Since ΔX is a minute value, it can be neglected in the case of normal marking. However, in the case of performing very strict marking, this interruption may be a problem. In order to address the above problem, in a third embodiment described below, the output of the laser 1 is gradually increased at the start of the movement of the beam, and the output of the laser 1 is gradually decreased at the stop of the beam. To prevent the occurrence of interruption.

FIG. 6 is a diagram showing the actual beam movement and the laser drive signal in the third embodiment of the present invention. Although FIG. 6 shows the beam movement by the X-axis mirror, the same applies to the Y-axis mirror. The same operation is performed. The operation of the third embodiment of the present invention will be described with reference to FIGS. At the start of the movement of the beam, the laser control means 33 gradually increases the output of the laser beam emitted from the laser 1 for a predetermined time after the output of the position control signal Sx as shown in FIG.

That is, after the galvanometer scanner starts to move, marking is performed with the output of the laser beam being low while the moving speed is low, and when the moving speed of the galvanometer scanner is accelerated and the beam moving speed is increased, The marking is performed in a state where the output of the laser beam is large. Therefore, if the irradiation amount of the laser beam is controlled to an appropriate value according to the material of the work,
As shown in FIG. 6, the line width and the mark depth of the mark to be marked on the work can be made uniform. The predetermined time takes a unique value according to the galvanometer scanner as described in the second embodiment.
７００700 μsec.

Also, the laser control means 33 gradually reduces the output of the laser beam radiated from the laser 1 a predetermined time before stopping the movement of the beam, as described above. As a result, similarly to the above, when the beam moving speed immediately before the stop of the beam is low, the output of the laser beam irradiated on the work becomes small, and the line width and the mark depth of the mark marked on the work are made uniform. can do. FIG. 6 shows the case where the output of the laser beam is increased at a constant speed. However, if the output of the laser beam is changed according to the change in the beam moving speed on the work, more uniform marking can be performed. Can be. Further, the beam moving speed at the time of starting / stopping the beam cannot be made completely constant only by the first embodiment described above. If the output of the laser beam is gradually increased / decreased at the start / stop of the movement, more precise marking can be performed.

[0024]

As described above, in the present invention,
The following effects can be obtained. (1) When the light beam starts moving from the vertex of the character / figure, a first signal in a direction for increasing the scanning speed of the light beam is added to the position control signal for a predetermined period, and the light beam When the character reaches the vicinity of the vertex of the character / figure, the second signal in the direction for reducing the scanning speed of the light beam is added to the position control signal for a predetermined period.
The scanning speed of the light beam in the vicinity of the vertex forming the figure can be made close to the scanning speed of the position control signal,
The line width and the marking depth of the mark in the vicinity of the vertex of the figure can be made substantially constant.

( 2 ) After the light beam starts moving from the vertex of the character / figure according to the position control signal, until the scanning speed of the light beam accelerates and reaches a predetermined speed, the galvanometer scanner is synchronized with the acceleration. Gradually increases the output of the light beam to be introduced into the apparatus, and adjusts the light beam scanning speed until the scanning speed of the light beam stops after the light beam reaches the vicinity of the vertex of the character / graphic. Therefore, the output of the light beam to be introduced into the galvanometer scanner is gradually reduced, so that even if the moving speed of the work becomes slow near the vertex of the character / figure, the line width and the marking of the mark to be marked on the work are reduced. The depth can be made substantially constant.

( 3 ) Position control for galvanometer scanner
Signal to be processed by the galvanometer scanner.
By controlling the irradiation position of the light beam on the object,
When marking characters / graphics on objects,
When the system starts moving from the top of the above character / graphic,
During a fixed period, the position control signal increases the light beam scanning speed.
Add the first signal in the direction to
After the system starts moving from the top of the character / graphic,
After a lapse of time, the light beam is guided to the galvanometer scanner.
The light beam begins to enter
When reaching the vicinity of the point, the position control signal
The second signal in the direction to reduce the scanning speed of the light beam is applied.
The light beam reaches the top of the character / graphic
The light to the galvanometer scanner
Because it was Unishi I to stop the input, it is possible to perform more precise marking. (4) By using the above (1) and ( 2 ) together, more precise marking can be performed.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of a first exemplary embodiment of the present invention.

FIG. 2 is a diagram for explaining the operation of the first embodiment of the present invention.

FIG. 3 is a diagram illustrating an operation when a beam repeatedly stops moving.

FIG. 4 is a diagram showing a configuration of a second and a third embodiment of the present invention.

FIG. 5 is a diagram illustrating the operation of the second embodiment of the present invention.

FIG. 6 is a diagram for explaining the operation of the third embodiment of the present invention.

FIG. 7 is a diagram illustrating a configuration of a marking device that controls movement of a beam irradiation position.

FIG. 8 is a diagram showing an arrangement of mirrors of the galvanometer scanner.

FIG. 9 is a diagram illustrating an example of a configuration of a galvanometer scanner.

FIG. 10 is a block diagram of a marking device.

FIG. 11 is a diagram showing an example of characters to be marked.

FIG. 12 is a diagram showing an actual movement of a laser beam and a trajectory of a mark.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Laser 2 Galvanometer scanner 2a, 2b X-axis mirror, Y-axis mirror 2c X-axis scanner 2d Y-axis scanner 2e Mirror drive unit 2f Position sensor unit 2g Comparison unit 3 System controller 3a Control unit 31 Position signal generation means 32 Start / stop signal Generation means 33 Laser control means Amp1, Amp2 Amplifier Sen Position sensor

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) B23K 26/00-26/36

Claims (6)

(57) [Claims] 1. A marking method for giving a position control signal to a galvanometer scanner, controlling the irradiation position of a light beam on the object by the galvanometer scanner, and marking characters / graphics on the object. When the light beam starts moving from the top of the character / figure, a first signal in a direction for increasing the scanning speed of the light beam is added to the position control signal for a predetermined period; When the light beam reaches the vicinity of the vertex of the character / figure, a second signal in a direction for reducing the scanning speed of the light beam is added to the position control signal for a predetermined period. 2. A marking method for giving a position control signal to a galvanometer scanner, controlling the irradiation position of a light beam on an object to be processed by the galvanometer scanner, and marking characters / graphics on the object to be processed. After the light beam starts moving from the vertex of the character / figure according to the position control signal, the light beam is introduced into the galvanometer scanner according to the acceleration until the scanning speed of the light beam accelerates to reach a predetermined speed. The output of the light beam is gradually increased. Further, from the time when the light beam reaches the vicinity of the vertex of the character / figure until the scanning speed of the light beam is reduced and stopped, the galvanometer is adjusted in accordance with the deceleration. A marking method characterized by gradually reducing the output of a light beam introduced into a scanner. 3. A marking method for giving a position control signal to a galvanometer scanner, controlling the irradiation position of a light beam on the object to be processed by the galvanometer scanner, and marking characters / graphics on the object to be processed. When the light beam starts moving from the vertex of the character / figure, a first signal for increasing the scanning speed of the light beam is added to the position control signal for a predetermined period, Starts moving the light beam to the galvanometer scanner after a predetermined time elapses after moving from the vertex of the character / graphic, and when the light beam reaches near the vertex of the character / graphic, During the period, a second signal in a direction for reducing the scanning speed of the light beam is added to the position control signal, and the light beam reaches the vertex of the character / graphic. Before the constant time, the marking method characterized by stopping the introduction of light into the galvanometer scanner. 4. A marking method for applying a position control signal to a galvanometer scanner, controlling the irradiation position of a light beam on the object to be processed by the galvanometer scanner, and marking characters / graphics on the object to be processed. When the light beam starts moving from the vertex of the character / figure, a first signal for increasing the scanning speed of the light beam is added to the position control signal for a predetermined period, Starts moving from the top of the character / figure and gradually increases the output of the light beam introduced into the galvanometer scanner in accordance with the acceleration until the scanning speed of the light beam accelerates and reaches a predetermined speed. When the light beam reaches the vicinity of the vertex of the character / figure, the position control signal is supplied to the position control signal for a predetermined period so as to reduce the scanning speed of the light beam. During as well as adding the second signal, from the light beam reaches the vicinity apexes of the character / graphics, to the scanning speed of the light beam is stopped to decelerate,
A marking method characterized by gradually reducing the output of a light beam introduced into a galvanometer scanner in accordance with the deceleration. 5. A light beam emitting unit for emitting a light beam, a galvanometer scanner for controlling an irradiation position of a light beam on an object to mark a character / figure on the object, and a galvanometer scanner. A control unit for supplying a position control signal to drive the galvanometer scanner, wherein the control unit is configured to control the position control signal when the light beam starts moving from the vertex of the character / graphic. A first signal in the direction of increasing the scanning speed of the light beam is output for a predetermined period of time, and when the light beam reaches the vicinity of the vertex of the character / graphic, the scanning speed of the light beam is reduced by the position control signal. And a start / stop signal generating means for outputting a second signal in a direction to be driven for a predetermined period, and adding the first and second signals to the position control signal to generate a signal. A marking device provided to a rubanometer scanner. 6. A light beam emitting unit that emits a light beam, a galvanometer scanner that controls an irradiation position of a light beam on an object to mark a character / graphic on the object, and a galvanometer scanner. A control unit for giving a position control signal to drive the galvanometer scanner, wherein the control unit starts moving the light beam from the vertex of the character / graphic by the position control signal, Until the scanning speed of the light beam accelerates and reaches a predetermined speed, the output of the light beam introduced into the galvanometer scanner is gradually increased in accordance with the acceleration, and the light beam reaches the vicinity of the vertex of the character / graphic. After that, until the scanning speed of the light beam decelerates and stops, the light beam introduced into the galvanometer scanner is synchronized with the deceleration. A marking device comprising a light beam control means for gradually reducing the output of a system.