JPH1187805A - Laser marker - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a space-saving highly accurate laser marker without the danger of the disconnection of a coil wire at a low cost. SOLUTION: A swinging motor 23 is swung so as to swing a laser beam for ±L/2 each with a 0 point as a center in an (x) axis direction determined on an irradiation object plate 31. In the meantime, a swinging motor 33 scans a range from the 0 point to a -y point at a low speed. Then, at the time of reaching a prescribed coordinate point (x, y), that is at the time of reaching a part to start printing, the irradiation of the laser beam for a prescribed quantity and a prescribed length is singly performed by a laser beam source 21. When the swinging motor 33 reaches the -y point, it is returned to the 0 point again at a high speed. Parallelly to the return of the swinging motor 33 to the 0 point, an offset for-x is applied to the swinging motor 23. Thereafter, the swinging motor 23 performs swinging for ±L/2 each with -x as the center.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laser marker, and more particularly to a high-precision laser marker which is space-saving, low-cost, and has no risk of coil wire breaking.

[0002]

2. Description of the Related Art Conventionally, iron, wooden, and laser markers have been used.
When engraving numbers, characters, figures, and the like on a substrate made of resin or the like, a high-speed, high-precision, high-priced oscillating motor is used to reflect laser light on a mirror fixed to a main shaft and perform printing. At this time, a vector scan method is adopted as a method of engraving. FIG. 4 illustrates the vector scan method by taking the case of engraving characters as an example. In the vector scan method, numbers,
Characters, figures, and the like are regarded as continuous quantities, and the end points such as numbers are continuously engraved at a stretch. In FIG. 4, a letter A is engraved by scanning a laser beam from the end point to the body or the like. Thereafter, a predetermined number of characters and the like are continuously engraved in the x direction. After the completion of the marking in the x direction, the x direction is returned to the starting point, and the laser beam is moved to the next stage (y direction), and the characters and the like are similarly marked again.

[0003]

However, in the vector scan system, the laser light emitted from the laser light source is reflected by a mirror to scan a large swing angle in both the x and y directions. high speed,
High precision and high price are required. In order to swing the mirror at a high speed, high torque and low inertia are required as the performance of the swing motor. Therefore, the oscillating motor has a large size (for example, a diameter of 40 mm and a length of 100 mm).
Millimeters), and the storage space also increases. In addition, the heat generated by the swing motor increases, and a cooling device is required. Further, a material having a high heat-resistant grade such as a material of a coil wire, a member for holding the coil wire, etc., which constitutes the rocking motor, is required. In order to reduce the inertia of the swing motor, a moving coil type as shown in FIG. 5 is often used. In FIG. 5, the coil 3 is fixed to the main shaft 1. The upper and lower parts of the main shaft 1 are supported by bearings 5. A permanent magnet 7 is fixed to the outer periphery of the coil 3, and a yoke 9 is provided inside the coil 3. By passing a current through the coil lead wire 11, a torque is generated between the coil 3 and the permanent magnet 7. When an alternating current is passed through the coil lead wire 11, the swing motor 10 can swing at a predetermined angle. At this time, the coil lead wire 11 frequently moves according to the swing of the swing motor 10.
Therefore, there was a risk of disconnection of the coil wire. The present invention has been made in view of such conventional problems, and has as its object to provide a high-precision laser marker that is space-saving, low-cost, and has no risk of coil wire breaking.

[0004]

SUMMARY OF THE INVENTION Accordingly, the present invention provides a laser light source for irradiating a laser beam, and oscillating the laser beam emitted from the laser light source at a predetermined angle only in one of an x-axis direction and a y-axis direction. A first oscillating motor in which a first mirror is attached to an end of a main shaft; and a laser beam reflected by the first mirror is used to oscillate the y-axis when the first oscillating motor oscillates in the x-axis direction. A second mirror attached to an end of a main shaft to swing a predetermined angle in the x-axis direction when the first rocking motor swings in the y-axis direction in the first or second direction, and The plate to be irradiated with the laser light reflected by the mirror 2 is oscillated at a predetermined angle in the x-axis direction at a high speed, and travels in the y-axis direction at a low speed and returns. Swing at high speed, and the swing in the x-axis direction and the swing in the y-axis direction are synchronized. When indicia only by irradiating a laser beam from the laser light source, and configured to include a control means for applying a predetermined offset to the x-axis direction when the y-axis direction of the back. Laser light is emitted from a laser light source. First
A first mirror is attached to the end of the main shaft of the swing motor. Then, the first mirror oscillates the laser light emitted from the laser light source by a predetermined angle in the x-axis direction or the y-axis direction. The first mirror swings only in either the predetermined x-axis direction or the y-axis direction. Also, the second
A second mirror is attached to the end of the main shaft of the swing motor. Then, the second mirror further reflects the laser light reflected by the first mirror. The second rocking motor is responsible for the y-axis direction when the first rocking motor is responsible for the rocking in the x-axis direction, and the first rocking motor is for the y-axis.
When it is responsible for the swing in the axial direction, it is responsible for the swing in the x-axis direction. The laser light reflected by the second mirror is applied to the irradiation target plate. The portion of the irradiation target plate irradiated with the laser light melts or burns. As a result, the irradiation target plate is stamped. The control means causes the first rocking motor and the second rocking motor to rock at a predetermined angle in the x-axis direction at a high speed, and moves forward and backward in the y-axis direction at a low speed. Swing at high speed. The preset angle in the x-axis direction can be set to a limited small range, and the speed in the y-axis direction can be always low. An oscillating motor can be used. Therefore, heat generation is small, and a cooling device is not required. Also, the smaller the swing angle, the better the linearity between the swing angle and the swing angle command value. In the control in the x-axis direction and the y-axis direction, the laser light is emitted from the laser light source only at the time of engraving while synchronizing the first rocking motor, the second rocking motor, and the laser light source. Then, when a series of engraving operations are completed in the y-axis direction and returned to the starting point of the y-axis, x
A predetermined offset is applied in the axial direction. The reason for offsetting in the x-axis direction is to write the next character or the like in the x-axis direction. In the case where a plurality of characters or the like exist in the y-axis direction, the engraving may be performed in the next stage (y-axis direction) after the engraving operation is repeated in the x-axis direction. At this time, a predetermined offset may be applied in the y-axis direction.

Further, according to the present invention, a permanent magnet having a plurality of poles is fixed to a main shaft of at least one of the first oscillating motor and the second oscillating motor, and a predetermined distance is provided on the outer periphery of the permanent magnet. The drive coil was wound uniformly. A permanent magnet having a plurality of poles is fixed to at least one main shaft of the first swing motor and the second swing motor. The permanent magnet is swingable. Further, the drive coil is wound uniformly around the outer periphery of the permanent magnet at a predetermined distance. That is, since the swing motor may be small in size and low in torque, a moving magnet type can be used. In the moving magnet type, since the lead wire of the coil is fixed, there is no disconnection due to the swing.

[0006]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a laser marker according to an embodiment of the present invention. In FIG. 1, a laser light source 21
Is designed to emit laser light. The swing motor 23 has a mirror 27 attached to the end of the main shaft 25.
The mirror 27 reflects the laser light emitted from the laser light source 21. The swing motor 33 has a mirror 37 attached to an end of the main shaft 35. The mirror 37 further reflects the laser light reflected by the mirror 27. The laser light reflected by the mirror 27 and the mirror 37 is applied to the irradiation target plate 3.
1 is reached. The irradiation target plate 31 is a substrate made of wood, iron, resin, or the like. FIG. 2 shows an internal configuration diagram of the swing motor 23 and the swing motor 33. Swing motor 2
Since the swing motor 3 and the swing motor 33 have the same configuration, the swing motor 23 will be described as an example. 2, the swing motor 23 can arbitrarily control the rotation angle of the main shaft 25. Two-pole magnets 47a and 47b are fixed to the main shaft 25 in a radial direction in a cylindrical shape. Coil substrates 43a and 43b are arranged on the outer periphery of the magnets 47a and 47b at a predetermined distance. The drive coils 45 are provided on the coil substrates 43a and 43b.
a and 45b are evenly wound. Magnets 47a, 47
Rotation angle detecting magnets 41a and 41b for detecting the rotation angle of the main shaft 25 are disposed below b. A position detection sensor 49 is provided on the outer periphery of the rotation angle detection magnets 41a and 41b at a predetermined distance.

Next, the operation will be described. In FIG. 1, laser light is emitted from a laser light source 21. Mirror 27
Reflects this laser light. The mirror 27 is oscillated by a predetermined angle in the x-axis direction (the vertical direction in FIG. 1) defined on the irradiation target plate 31 by the oscillating motor 23. The predetermined angle depends on the distance between the mirror 27 and the mirror 37 and the distance between the mirror 37 and the irradiation target plate 31, but is an angle at which the range indicated by L in FIG. 1 can be scanned. The mirror 37 further reflects the laser light reflected by the mirror 27. The mirror 37 is swung at a predetermined angle by a swing motor 33 in the y-axis direction defined on the irradiation target plate 31. The predetermined angle depends on the distance between the mirror 37 and the irradiation target plate 31, but is an angle at which the range from the point 0 to the point -y in FIG. 1 can be scanned. When the laser beam reflected by the mirror 37 hits the irradiation target plate 31, the irradiated portion burns or melts, and characters or the like can be marked on the irradiation target plate 31. However, the present invention is not limited to the engraving, and may be other printing, printing, processing, or the like irradiated with laser light. Although the irradiation target plate 31 in FIG. 1 is a flat surface, it may be a cylinder or the like, and the shape of the irradiation target plate is not limited.

The oscillating motor 23 (also the oscillating motor 33) is scanned as follows. In FIG. 2, when a current is supplied to the drive coils 45a and 45b, a torque is generated between the drive coils 45a and 45b and the magnets 47a and 47b. If the current is stopped at a predetermined value, the main shaft 25 stops, and the drive coil 45a,
If an alternating current is passed through 45b, it is possible to perform a rocking motion of less than 180 degrees. When the main shaft 25 swings, an output proportional to the magnetic flux density is obtained from the position detection sensor 49. Therefore, by controlling the current of the drive coils 45a and 45b so that the output signal from the position detection sensor 49 becomes a predetermined value, it is possible to control the main shaft 25 to stop at a desired position. In addition, it is also possible to perform a simple reciprocating motion within a certain angle range by inputting the control signal to the drive coils 45a and 45b as an alternating current.

Next, a method for controlling a laser marker according to an embodiment of the present invention will be described. FIG. 3 shows a control flow of the laser marker. For example, a case in which characters A, B, and the like are engraved on the irradiation target plate 31 in a horizontal row will be described. The oscillating motor 23 oscillates around the zero point in the x-axis direction defined on the irradiation target plate 31 such that the laser light swings by ± L / 2. In this case, the dimension L is a predetermined length at a place where the division is good (for example, in a range of one character). The reason why the swing angle range of the swing motor 23 is limited to L is that the swing angle range is narrowed so that a small swing motor having no force can swing at high speed, and the linearity in the swing angle range is reduced. To make it better. As for the linearity in the swing angle range, the smaller the swing angle range, the better the linearity of the swing angle with respect to the input signal. On the other hand, the swing motor 33 scans the range from the point 0 to the point −y defined on the irradiation target plate 31 at a low speed. When a predetermined coordinate point (x, y) is reached, that is, when the print position is reached, the laser light source 21 irradiates a predetermined amount and a predetermined length of laser light in a single shot. The printing position, the predetermined amount and the predetermined length are determined by discretely separating the character A in advance. Therefore, the character A does not become a continuous line as in the vector scan system, but can be made to appear as a continuous line by increasing the density of the stamp. When the swing motor 33 reaches the point -y, it returns to the point 0 at a high speed again. The return time at this time is extremely short, and hardly affects the motor capacity. Therefore, a small swing motor is sufficient for the swing motor 33. That is, both the swing motor 23 and the swing motor 33 can be configured as a small laser marker having a diameter of about 15 mm and a length of about 20 mm to form a laser marker. Accordingly, both the swing motor 23 and the swing motor 33 generate less heat, and a cooling device is not required. In parallel with returning the swing motor 33 to the zero point, the swing motor 23 is offset by -x. Thereafter, the oscillating motor 23 oscillates by ± L / 2 around −x, and the oscillating motor 33 scans the range from the point 0 to the −y point at a low speed.
Then, the character B is stamped in the same manner as the character A described above. By repeating the above processing, characters and the like can be marked on the irradiation target plate 31. In addition, when engraving characters etc. in the next step,
At the end of the first stage marking, a predetermined amount of offset may be applied in the y-axis direction in parallel with returning the offset in the x-axis direction to zero. In addition, the swing motor 2 viewed from the laser light source 21
The arrangement order of 3 and the swing motor 33 may be reversed. At this time, the swing in the y-axis direction is performed first, and then the swing in the x-axis direction is performed. Further, the moving magnet type is used for the swing motor 23 and the swing motor 33, so that the coil lead wire does not move and there is no fear of disconnection.

[0010]

As described above, according to the present invention, the first rocking motor and the second rocking motor are rocked at a predetermined angle with respect to the x-axis direction at a high speed. In the axial direction, the swinging is performed at a low speed in the going direction and at a high speed in the returning direction, so that a small swinging motor with low torque can be used. Therefore, the laser marker can save heat at a small space and at low cost. Further, the linearity of the swing angle with respect to the input signal is improved as the swing angle range is limited, so that the accuracy of the marking can be increased. By using the moving magnet type for the swing motor, there is no need to worry about disconnection of the coil lead wire.

[0011]

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a laser marker according to an embodiment of the present invention.

FIG. 2 is an internal configuration diagram of a swing motor.

Fig. 3 Laser marker control flow

FIG. 4 is an explanatory diagram of a marking method of a vector scan method.

FIG. 5 is an internal configuration diagram of a moving coil type swing motor.

[Explanation of symbols]

 21 Laser light source 23, 33 Swing motor 25, 35 Main shaft 27, 37 Mirror 31 Irradiation target plate 45a, 45b Drive coil 47a, 47b Magnet

Claims (2)

[Claims] 1. A laser light source for irradiating a laser beam,
A first oscillating motor having a first mirror attached to an end of a main shaft for deflecting a laser beam emitted from the laser light source in one direction only in an x-axis direction or a y-axis direction; The laser light reflected by the mirror is predetermined in the y-axis direction when the first swing motor swings in the x-axis direction, or in the x-axis direction when the first swing motor swings in the y-axis direction. A second oscillating motor in which a second mirror is attached to an end of a main shaft for oscillating an angle, an irradiation target plate irradiated with laser light reflected by the second mirror, and an x-axis direction. It swings at a high speed by a preset angle, swings at a low speed in the y-axis direction, and swings at a high speed in the return direction. The swing in the x-axis direction and the swing in the y-axis direction are synchronized. A laser beam is emitted from the laser light source only at the time of engraving, and the x-axis is Laser marker, comprising the control means for applying a predetermined offset to the direction. 2. A permanent magnet having a plurality of poles is fixed to at least one of the main shafts of the first swing motor and the second swing motor, and a drive coil is equally spaced at a predetermined distance from an outer periphery of the permanent magnet. The laser marker according to claim 1, wherein the laser marker is wound.