JPH0852578A - Laser marking device and its method - Google Patents

Abstract

PURPOSE:To provide a marking device and its method by which the kinds of marking letters and symbols are changed at extremely high speed. CONSTITUTION:The device is provided with a laser light source 50, first stencil unit 10 with revolving stencils 11, 12, second stencil unit 20 with revolving stencils 21, 22, and light path switching mirrors 31, 32 by which the light path of the laser beam is switched between the first light path 15 that goes by way of the first stencil unit 10 and the second light path 25 that goes by way of the second stencil unit 20. The laser marking method is such that a marking processing is successively performed on continuously supplied objects and that the kinds of letters and symbols to he marked are changed by switching the light path of a laser beam through the light path switching mirrors 31, 32 by means of the laser marking device.

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 and a laser marking method, and more particularly to a marking device and a marking method capable of changing the types of characters and symbols to be marked at extremely high speed.

[0002]

2. Description of the Related Art Marking by a laser is capable of high-speed processing, has few marking mistakes, and has a low operating cost. In recent years, marking has been actively performed in place of conventional marking with ink or marking with machine. .

FIG. 1 is a plan view showing the outline of a conventional laser marking device. This marking device is a device that sequentially marks two-digit numbers on an object W that is continuously supplied. Here, the object W is an electronic component such as a capacitor, and the two-digit number to be marked indicates the manufacturing date of the electronic component.

In FIG. 1, 1 is a laser light source comprising a carbon dioxide laser oscillator, 2 is a cylindrical lens, 3 is an imaging lens, and 4 is a stencil unit. The stencil unit 4 includes a rotary stencil 4A (for tens),
Rotating stencil 4B (for unit digit) and motors 4AM, 4
It has BM and control systems 4AC and 4BC.

As shown in FIG. 2, the rotary stencil 4A
In (for tens place), three sets of translucent parts representing numbers from 0 to 3 are arranged along the periphery thereof, and the rotary stencil 4B
In (for one's place), light-transmitting portions representing numbers from 0 to 9 are arranged along the periphery thereof. Therefore, by combining the rotary stencil 4A and the rotary stencil 4B, a number (date) from "01" to "31" can be marked.

When the product related to the object W continuously supplied to the marking device is switched to a product having a different manufacturing date (usually, a product manufactured on the day following the date of marking). , It is necessary to change the type of numbers to be marked accordingly.

Here, the type of numeral of "tens place" can be changed by rotating the rotary stencil 4A by the motor 4AM controlled and operated by the control system 4AC. On the other hand, the type of the digit of “one's place” can be changed by rotating the rotary stencil 4B by the motor 4BM controlled and operated by the control system 4BC.

For example, the procedure for changing the type of the digit of "one's place" is as follows. (1) The reference origin (0 degree) on the rotary stencil 4B is detected by the origin sensor s1. (2) A rotating stencil that is required to position the light-transmitting portion that represents the number [n + 1] to be marked next, on the optical path of the laser light, in place of the light-transmitting portion that represents the number [n] that is being marked. The rotation angle of 4B is obtained by the control system 4BC. (3) Send the signal corresponding to the rotation angle obtained in (2) to the motor 4B.
Then, the rotary stencil 4B is rotated to the rotation angle. As a result, the number [n +
1] will be located. (4) In order to make the stop position of the translucent part representing the number [n + 1] with respect to the optical path of the laser light appropriate, the position error due to mechanical error is corrected (fine adjustment). For example,
The position sensor s2 detects position deviation data (position deviation direction / amount) with respect to an appropriate stop position based on a positioning mark provided corresponding to the translucent portion,
These data are fed back to the control system 4BC.
The control system 4BC uses the motor 4BM to correct the positional deviation.
The control signal is sent to the motor 4BM, and the motor 4BM that receives the control signal makes a minute rotation to correct the positional deviation. The procedure for changing the type of the "tens place" is almost the same as the above.

[0009]

However, the supply speed of the objects W supplied to the marking device shown in FIG. 1 is, for example, about 20 sheets per second, and therefore the processing time per marking is about 50 msec. It is said that

However, in the conventional marking apparatus as shown in FIG. 1, since the type of numeral is changed by the mechanical means of rotating the stencil using the motor,
It takes a long time (50ms) to switch the date.
(time exceeding ec) is required. Then, during this period, there is a problem that the marking processing cannot be performed on the object supplied to the apparatus, and products without date display are generated and mixed.

In order to solve such a problem, it is conceivable that the supply of the object is temporarily stopped when the date is switched, but the marking process is usually operated at a very high takt speed for 24 hours. Since it is one step of the production line, it is practically impossible to stop the supply of the object because the whole line is stopped.

The reason why the switching time exceeding 50 msec is required when switching the marking date by a mechanical means is considered as follows. (1) Operating time For example, when switching from “30 days” to “01 days” using the rotary stencils 4A and 4B as shown in FIG. 2, the rotary stencil 4A is replaced with a light-transmitting part representing the number [3]. Therefore, it is necessary to rotate 30 degrees (360/12) in order to position the light-transmitting part that represents the number [0] on the optical path of the laser light. In the rotating stencil 4B, replace the light-transmitting part that represents the number [0] with the light-transmitting part. Therefore, it is necessary to rotate by 36 degrees (36/10) in order to position the light-transmitting portion representing the number [1] on the optical path of the laser light. With such a rotation angle, it is possible to set the operation time within 50 msec.

However, when switching from "28th" (end of February) to "01th", in the rotating stencil 4A, the translucent part representing the number [2] is replaced with the translucent part representing the number [0]. Rotation of 60 degrees ([2] → [3] → [0]) is required to position the laser beam on the optical path, and in the rotating stencil 4B, a numeral [8] is used in place of the transparent portion. 1] is rotated by 108 degrees ([8] → [9] → [0] → to position the light-transmitting portion on the optical path of the laser light.
[1]) is required. When the rotation angle (moving distance of the transparent portion) is large, the operation time is 5
It is extremely difficult to set the time within 0 msec.

(2) Vibration Suppression Time The rotating stencil vibrates for a while after the completion of the rotation operation by the motor, and even if the marking process is performed in such a state, it is positioned on the optical path of the laser beam. Accurate processing cannot be performed because the translucent part is not completely stationary. That is, as the time required to switch the date, not only the above operation time but also the time until the vibration of the rotary stencil subsides (vibration suppression time) must be considered. However, when the present inventors conducted experiments under various conditions, it was found that the vibration suppression time (for example, the amplitude of the translucent portion was 0.1 mm after the end of the rotation operation).
50 to 150 ms as the time to settle within
It was confirmed that ec was required. Although it is possible to forcibly stop the vibration of the rotary stencil by providing the cam mechanism, in such a case, the apparatus becomes complicated and large, which is not preferable.

The present invention has been made based on the above circumstances. It is an object of the present invention to provide a marking device capable of changing the type of a character or symbol to be marked at an extremely high speed, regardless of the length of the operation time of the stencil and the vibration suppression time. Another object of the present invention is to provide a marking method capable of changing the types of characters and symbols to be marked extremely quickly.

[0016]

A laser marking apparatus according to the present invention comprises a laser light source and a first rotating stencil having light-transmitting portions representing a plurality of types of characters and symbols arranged along a peripheral edge thereof. The second stencil unit (2) having a stencil unit (10) and a rotating stencil in which light-transmitting portions representing a plurality of types of characters and symbols are arranged along the periphery.
0) and the optical path of the laser light from the laser light source to the marking object, the first stencil unit (10)
It is characterized by comprising an optical path switching mirror (31, 32) for switching between a first optical path passing through the second stencil unit (20) and a second optical path passing through the second stencil unit (20).

A laser marking method according to the present invention is a laser marking method for sequentially performing marking processing on an object which is continuously supplied, wherein an optical path switching mirror (31, 32) is used by using the laser marking device. By switching the optical path of the laser light, the type of characters and symbols to be marked is changed.

[0018]

Operation: The optical path of the laser beam is selected by the optical path switching mirror, and marking processing is performed using either one of the two stencil units, and in the meantime, the other waiting unit attempts to perform marking next. It is set so that the light-transmitting portion representing the character / symbol to be placed is located on the optical path of the laser light to be switched next. Then, after switching the optical path of the laser light by the optical path switching mirror,
The marking process is performed using the other unit. In this way, since the type of characters / symbols to be marked is changed using the optical path switching mirror, it is possible to change the type of characters / symbols to extremely high speed regardless of the operation time and vibration suppression time of the rotary stencil. You can That is,
(1) The operation time of the optical path switching mirror is extremely shorter than that of the rotary stencil, and (2) the rotary stencil of the other unit is completely stationary, so it is not necessary to consider its vibration suppression time. In addition, (3) Even if a slight vibration occurs in this optical path switching mirror after the operation of the optical path switching mirror, as long as a certain amount of laser light passing through the light transmitting part of the rotating stencil reaches the object. , Accurate marking process is performed.

[0019]

Hereinafter, embodiments of the present invention will be described.
The present invention is not limited to these.

FIG. 3 is an explanatory perspective view showing an example of the marking device of the present invention, and FIG. 4 is a schematic plan view of this device. This marking device is applied to the target objects W (electronic parts) that are continuously supplied at a rate of 20 sheets per second, in sequence.
It is a device for marking digits (manufacturing date). The numbers indicating the year of manufacture and the month of manufacture are marked by another stencil (not shown).

In FIGS. 3 and 4, reference numeral 50 designates TEA.
-CO ₂ laser light source, 10 is a first stencil unit, 20 is a second stencil unit, 3
Reference numerals 1 and 32 are optical path switching mirrors, 33 and 34 are mirror driving mechanisms, 41, 42, 43 and 44 are fixed mirrors, 61 is a cylindrical lens, and 62 is an imaging lens.

The first stencil unit 10 has a rotary stencil 11 (for tens place: diameter 220 mm), a rotary stencil 12 (for one place: diameter 220 mm), and motors 11M and 12M. Motor 11M, 12M
Is composed of, for example, a pulse motor or a servo motor, and is controlled by a control system (not shown) to rotate the rotary stencils 11 and 12.
Can be rotated and stopped at any angular position. The rotary stencil 11 is similar to the rotary stencil 4A shown in FIG.
In the same manner as the rotary stencil 4B shown in FIG. 2, light-transmitting portions representing numbers 0 to 9 are arranged along the periphery thereof. Therefore, by combining the rotary stencil 11 and the rotary stencil 12, from “01” to “3
Numbers (dates) up to 1 ”can be marked. Here, the kind of the number of "tens place" is the motor 11M.
Can be changed by rotating the rotary stencil 11, and the type of the digit of “one place” is the motor 1
It can be replaced by rotating the rotary stencil 12 with 2M.

The second stencil unit 20 has a rotary stencil 21 (for tens place: diameter 220 mm), a rotary stencil 22 (for one place: diameter 220 mm), and motors 21M and 22M. Motor 21M, 22M
Is composed of, for example, a pulse motor or a servo motor, and is controlled by a control system (not shown) to rotate the stencils 21 and 22.
Can be rotated and stopped at any angular position. Similar to the rotary stencil 4A shown in FIG. 2, the rotary stencil 21 has three sets of light-transmitting portions representing numbers 0 to 3 arranged along the periphery thereof, and the rotary stencil 22 has
In the same manner as the rotary stencil 4B shown in FIG. 2, light-transmitting portions representing numbers 0 to 9 are arranged along the periphery thereof. Therefore, by combining the rotary stencil 21 and the rotary stencil 22, from “01” to “3
Numbers (dates) up to 1 ”can be marked. Here, the type of the number of "tens place" is the motor 21M.
It can be changed by rotating the rotary stencil 21, and the type of the digit of "one place" is the motor 2
It can be replaced by rotating the rotary stencil 22 with 2M.

The optical path switching mirrors 31 and 32 fix the optical path of the laser light from the laser light source 50 to the object W to the first optical path 15 passing through the fixed mirror 41, the rotary stencils 11 and 12, and the fixed mirror 42. It is means for switching between the mirror 43, the rotating stencils 21, 22 and the second optical path 25 passing through the fixed mirror 44.

The optical path switching mirror 31 has an angular position facing the fixed mirror 41 by the mirror driving mechanism 33,
The optical path switching mirror 32 is rotated by an angle position facing the fixed mirror 43, and the optical path switching mirror 32 is moved by the mirror driving mechanism 34.
The angular position facing the fixed mirror 42 and the fixed mirror 44
To rotate between the angular position facing. Here, the rotation angle (beam deflection angle) of the optical path switching mirrors 31, 32 is, for example, 80 to 100 degrees, and the time required for rotation is extremely short, about 15 to 40 msec. As described above, as the mirror drive mechanisms 33 and 34 that can rotate the optical path switching mirrors 31 and 32 at high speed, for example, a galvanometer drive mechanism can be used.

With the marking device having the above-described configuration, marking processing and date switching are performed as follows. (1) The optical path switching mirrors 31 and 32 are fixed at angular positions as shown in FIG. 4 (a), and the first optical path 15 passing through the rotary stencils 11 and 12 is selected as the optical path of the laser light. The object W is marked with "28", which is the date of the last day of the month. Specifically, the rotary stencil 11
The translucent part that represents the number [2] and the rotating stencil 1
2 and the light-transmitting portion representing the number [8] in the first optical path 15
Position it on top. (2) The rotating stencil 2 is on standby while the marking process using the rotating stencils 11 and 12 is being performed.
The dates of 1 and 22 are set to "01" of the next day. Specifically, the light-transmitting portion that represents the number [0] on the rotary stencil 21 and the light-transmitting portion that represents the number [1] on the rotary stencil 22 are positioned on the second optical path 25. (3) At the time when the object W relating to the product manufactured on the next day (1 day) is supplied, the optical path switching mirrors 31 and 32 are rotated and fixed until they reach the angular position as shown in FIG. , Switching to the second optical path 25 as the optical path of the laser light,
"01" is the object W using the rotating stencils 21 and 22.
Marking processing on. (4) The rotating stencil 1 is on standby while the marking process using the rotating stencils 21 and 22 is being performed.
1 and 12 are set to the date "02" of the next day. Less than,
Similarly, every time the number (date) to be marked is changed, the optical path (rotating stencil) of the laser light is switched to continue the marking process.

According to this embodiment, the optical path switching mirror 3
Since the numbers to be marked are changed using 1, 32,
It is possible to change the date to the object W at an extremely high speed regardless of the length of the operation time and the vibration suppression time of the rotary stencil. That is, (1) optical path switching mirrors 31, 32
The operating time of is about 20 mes, which is extremely short compared to the operating time of the rotary stencil, and (2) the rotary stencil in standby at the time of switching is completely stationary, so it is necessary to consider the vibration suppression time. Moreover, it is not necessary to provide a cam mechanism or the like for forcibly stopping the vibration. Furthermore, (3) Optical path switching mirror 3 after the switching operation is completed.
Even if slight vibrations occur in 1 and 32, accurate marking processing is performed as long as a certain amount of laser light passing through the light transmitting portion of the rotary stencil reaches the object. Further, in the case of the rotating stencil in standby, it is not necessary to consider the length of the operation time and the vibration suppression time. Therefore, the control means for the rotational drive of the rotary stencil can have a simple structure.

[0028]

According to the present invention, the type of characters or symbols to be marked can be changed extremely quickly regardless of the length of the stencil operation time and vibration suppression time.
Further, since it is not necessary to consider the vibration suppression time of the stencil, it is not necessary to provide a cam mechanism or the like for forcibly stopping the vibration of the stencil, and the device can be simplified and downsized.

[Brief description of drawings]

FIG. 1 is a plan view showing an outline of a conventional laser marking device.

FIG. 2 is an explanatory diagram showing an arrangement state of translucent parts in a rotary stencil.

FIG. 3 is an explanatory perspective view showing an example of a marking device of the present invention.

FIG. 4 is a schematic plan view showing an example of a marking device of the present invention.

[Explanation of symbols]

 10 1st stencil unit 11, 12 rotary stencil 11M, 12M motor 20 2nd stencil unit 21, 22 rotary stencil 21M, 22M motor 31, 32 optical path switching mirror 33, 34 mirror drive mechanism 41-44 fixed mirror 50 laser light source 61 Cylindrical lens 62 Imaging lens

Claims (2)

[Claims] 1. A laser light source, a first stencil unit (10) having a rotating stencil in which light-transmitting portions representing a plurality of types of characters and symbols are arranged along a peripheral edge, and a plurality of types of characters and A second stencil unit (20) having a rotating stencil in which light-transmitting portions representing symbols are arranged along the peripheral edge, and an optical path of laser light from the laser light source to a marking target are defined by the first stencil unit. A first optical path through the stencil unit (10) and the second stencil unit (20)
A laser marking device comprising: an optical path switching mirror (31, 32) for switching between the optical path and a second optical path. 2. A laser marking method for sequentially performing marking processing on objects that are continuously supplied, wherein the laser marking apparatus according to claim 1 is used, and a laser is provided by an optical path switching mirror (31, 32). A laser marking method characterized by changing the type of characters and symbols to be marked by switching the optical path of light.