JP2001096389A - Method and equipment for laser beam machining for rotary body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a laser beam machining equipment for a rotary body which performs machining accurately and efficiently without stopping the rotation of work and moving optical system of laser beam. SOLUTION: This laser beam machining equipment performs machining by irradiating multiple targets where machining is needed on the rotating work, which is powered by rotary driving system, with pulse laser beam. On the side of incidence of pulse laser beam that irradiates the work, arrange a rotating mask 10 with multiple pinhole 10a that regulate beam pattern by which multiple targets on the work are irradiated. Each of the multiple pinholes corresponds with each of the multiple targets on the work one by one. The equipment has the synchronous system 14 that the rotation powered by rotary driving system synchronizes with maintains that of rotating mask so that the laser beam that passes through a pinhole can irradiate a corresponding target that needs to be machined on the work.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laser processing method and a laser processing apparatus for irradiating a laser beam onto a rotating workpiece mounted on a rotary table.

[0002]

2. Description of the Related Art In applications where processing is completed by irradiating a single or a plurality of pulsed laser beams onto the same portion to be processed of a workpiece (eg, spot welding, percussion drilling, etc.), the workpiece rotates. There is a case that it is necessary to process while performing. When the workpiece is moving at a certain speed due to the rotation of the workpiece, the irradiation position of the pulsed laser light extends in the moving direction of the workpiece, due to the irradiation time of the pulsed laser light or the time width of the pulse, Precise processing cannot be performed.

[0003]

For example, assuming that the pulse width of the pulsed laser beam is W ₁ (msec) and the moving speed of the processed part is v, as shown in FIG. The shape of ₁ is d ₂ = d ₁ + v · W
It becomes length d ₂ of substantially rectangular shape defined by _1.

[0004] In order to prevent this, it is difficult to rotate an optical system such as an optical fiber for transmitting pulsed laser light, a reflection mirror, and a lens so as to follow a rotating work.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a laser processing method for a rotating body capable of performing high-precision and efficient processing without stopping the rotation of a workpiece and without rotating an optical system of pulsed laser light. It is to provide a method and a processing device.

Another object of the present invention is to provide a laser processing method and a processing apparatus which can eliminate the influence of the irradiation time of the pulsed laser beam or the time of the pulse width and realize highly accurate processing.

[0007]

According to the present invention, a plurality of processed parts of a rotating work or a plurality of processed parts of a rotating work are irradiated with laser light to perform processing. A laser processing method for a rotating body, wherein a pulsed laser light is used as the laser light, and a laser beam is emitted once per rotation to a portion to be processed of the work. Provided.

In this laser processing method, the laser beam is rotated in synchronization with the rotating workpiece and passes through a rotary mask having a plurality of laser light passage areas and an imaging lens disposed below the rotary mask. Thus, the laser light irradiation is performed.

According to the present invention, a laser beam is applied to a plurality of processed parts of a work rotating by a rotary drive mechanism or a plurality of processed parts of a work rotated by a rotary drive mechanism. A laser processing apparatus for performing processing, wherein a rotating mask having a plurality of laser light passages that defines a beam pattern for irradiating a portion to be processed of the work is arranged on a laser light incident side of the work, The laser light passing area corresponds to a plurality of processed parts of the work or the processed parts of the plurality of works on a one-to-one basis. A laser for a rotating body, comprising: synchronous driving means for synchronizing rotation of the rotary driving mechanism and rotation of the rotary mask so as to irradiate a processing portion. Engineering equipment is provided.

The laser light passage area is a pinhole, and an image of the pinhole is formed between the laser light passing through the pinhole and the work on a portion to be processed of the work. Are arranged.

In addition, by using a pulsed laser beam as the laser beam, it is possible to irradiate a portion to be processed of the work with one laser beam per rotation of the rotary table.

The source of the pulsed laser light is preferably a YAG pulse laser oscillator.
A rotation sensor for detecting a rotation amount is provided at a rotation drive source of the rotation mask, and a detection signal from the rotation sensor is transmitted to the YAG.
By using the pulse as the laser oscillation trigger signal of the pulse laser oscillator, the laser beam can be emitted when the image of the laser beam passage area of the rotary mask reaches a position that overlaps the processed part of the workpiece.

The synchronous drive means may include a third gear interposed between a first gear provided on a rotary shaft of the rotary mask and a second gear provided on a rotary shaft of the rotary drive mechanism. These gears are driven to rotate, and the first gear and the second gear are realized by selecting the gear ratio of each gear so that they rotate in the same rotational direction at 1: 1.

If the radius r1 from the center of rotation of the rotary mask to the laser beam passage area and the radius r2 from the center of rotation of the workpiece to the radius r2 from the workpiece are different, the synchronous driving means may be used. Drives one of the gears to rotate by interposing a third gear between a first gear provided on a rotation shaft of the rotary mask and a second gear provided on a rotation shaft of the rotation drive mechanism. The distance L between the rotation center of the rotating mask and the rotation center of the work and the image forming ratio are set to predetermined values, respectively, and the rotation speed of the rotation mask and the rotation speed of the work are the same. It is realized by rotating in the same direction.

[0015]

FIG. 1 shows an embodiment of a laser processing apparatus for a rotating body according to the present invention. The apparatus includes a rotating mask 10 having a plurality of pinholes 10a,
An image forming lens 12 disposed between the rotary mask 10 and the work 11 to form an image of 0a on a processed portion of the work 11 as a work, a rotary table 13 for mounting the work 11, A synchronous drive system 14 for synchronizing the rotation of the rotary mask 10 with the rotation of the rotary table 13;
A photoelectric sensor 15 for synchronizing the rotation of the rotary mask 10 with the oscillation of a laser pulse in a pulse laser oscillator (not shown) is provided. Note that a YAG pulse laser oscillator is preferable as the pulse laser oscillator, but is not limited thereto.

FIG. 2 is a diagram showing the relationship between the rotary mask 10 and the work 11. Here, a case where processing is performed on a plurality of locations of the work 11 mounted on the rotary table 13 will be described. The rotating mask 10 is formed with a plurality of pinholes 10a that define the passband of the pulsed laser light at intervals in the circumferential direction. On the other hand, the work 11
A plurality of portions spaced apart in the circumferential direction form the processed portion 11a.
Then, processing with a pulsed laser beam, for example, drilling is performed on each of the portions to be processed. For this reason, the plurality of pinholes 10a correspond one-to-one to the plurality of processing portions 11a of the workpiece 11.

Here, the synchronous drive system 14 is provided between a first gear 16 provided on a rotary shaft 10-1 of the rotary mask 10 and a second gear 17 provided on a rotary shaft 13-1 of the rotary table 13. The first gear 16 is rotatably driven by a motor or the like with a third gear 18 interposed therebetween, and the gear ratio of each gear is selected. That is, the first gear 16 and the second gear 16
The gear ratio of the gear 17 is 1: 1 and always rotated in the same rotation direction.
The setting is set such that the image of “a” and the respective processed portions 11 a of the work 11 are located at positions overlapping each other during one rotation.

As shown in FIG. 2, the imaging ratio, the radius r1 from the center of rotation of the rotary mask 10 to the pinhole 10a, and the radius r2 from the center of rotation of the workpiece 11 to the portion to be processed 11a are as shown in FIG. , R2 are different, the distance L between the rotation axis 10-1 and the rotation axis 13-1 is required to overlap the image of the pinhole 10a and the processing target portion 11a.
Is set to L = r1 + r2, and the image forming ratio = r2 / r1
This is realized by: Also in this case, the rotating shaft 10-
1 and the rotation speed of the rotating shaft 13-1 are the same and in the same rotation direction.

The photoelectric sensor 15 irradiates light to a projection 19 provided on the first gear 16 and detects that reflected light from the projection 19 has entered to detect one rotation of the rotary mask 10. . In particular, this detection is performed when the image of one pinhole 10a of the rotary mask 10 and the one processed part 11a of the work 11 come to a position overlapping each other, and the generation cycle of the detection signal is set to By dividing the frequency by the number, the frequency-divided signal of the detection signal from the photoelectric sensor 15 can be used as a trigger signal of the laser pulse in the pulse laser oscillator. In this way, the pulsed laser light from the pulse laser oscillator passes through each pinhole 10a when the image of each pinhole 10a of the rotary mask 10 and each processing portion 11a of the workpiece 11 come to a position where they overlap each other. Thus, each workpiece 11a of the workpiece 11 is irradiated.

As a result, one processing portion 11a has:
One rotation of the work 11 emits one pulsed laser beam. However, the beam diameter φD of the pulsed laser light is
Distance L over which pinhole 10a moves at laser irradiation time t
It is adjusted to a size that can cover.

Referring to FIGS. 3 and 4, for convenience, a case in which the number of the pinhole 10a and the portion to be processed 11a is one will be described. Since the rotating mask 10 is rotating, the pinhole 10a moves from P1 to P2 at a certain time, and its trajectory becomes an arc P1P2. The image of the arc P1P2 is formed by the imaging lens 12
As a result, the arc P1′P2 ′ on the work 11 is obtained, and the locus of the image becomes the arc P1′P2 ′. In addition, a certain time is
This is the irradiation time per pulsed laser beam.

In particular, the image forming ratio by the image forming lens 12 is 1:
In the case of 1, the result is as shown in FIG. Since the rotating mask 10, the rotating table 13 and the work 11 are rotating synchronously,
The point where the laser light is irradiated within the irradiation time of the pulsed laser light is the same point on the work 11 even if the work 11 is rotating. As a result, the problem described with reference to FIG. 5 does not occur.

The work 11 is not always in a circular shape as shown. For example, a plurality of works may be arranged at equal angular intervals on the same circumference centered on the rotation center on the turntable 13 in some cases.
In such a case, a plurality of pinholes are provided in the rotating mask 10 as described above. The rotary mask 10 is not limited to a pinhole, and a hole having a pattern corresponding to a processing pattern for a workpiece is provided.

Further, the spot diameter of the pulsed laser beam on the portion to be processed can be changed by changing the image forming ratio of the image forming lens 12. When the imaging ratio is other than 1: 1, the pinhole 10 on the rotary mask 10
This can be handled by optimizing the radial position of a.

Further, in the above embodiment, the case where pulsed laser light is used has been described, but the laser light may be continuous light. In this case, the rotary mask 10 is continuously irradiated with the laser beam. However, the operation after passing through the pinhole 10a is the same, and the trigger by the photoelectric sensor 15 is unnecessary.

[0026]

According to the present invention, accurate and efficient machining can be performed without stopping the rotation of the work and without rotating the optical system of the laser beam. In the case of the laser beam, the effect of the irradiation time or the time of the pulse width is eliminated, and accurate processing can be realized.

[Brief description of the drawings]

FIG. 1 is a diagram showing an embodiment of a laser processing apparatus according to the present invention.

FIG. 2 is a diagram showing a relationship between a rotary mask and a work in FIG. 1;

FIG. 3 is a view for explaining an operation when a rotating work is irradiated with a laser beam through a rotary mask in FIG. 1 in the case of a single pinhole.

FIG. 4 is a diagram for explaining the relationship between the rotating mask, the imaging lens, and the rotating work in FIG. 1 in the case of one pinhole.

FIG. 5 is a diagram for explaining an irradiation pattern when a pulsed laser beam is irradiated on a stationary object and a moving object.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Rotation mask 10a Pinhole 11 Work 11a Worked part 12 Imaging lens 13 Rotary table 14 Synchronous drive system 15 Photoelectric sensor 16, 17, 18 First, second, and third gear 19 Projection

Claims (9)

[Claims] 1. A laser processing method for irradiating a laser beam to a plurality of processed parts of a rotating work or a processed part of a plurality of rotating works to perform processing. A laser processing method for a rotating body, characterized in that a pulsed laser beam is used as a laser beam, and a laser beam is emitted once per rotation to a portion to be processed of the work. 2. A laser processing method according to claim 1, wherein said rotating mask rotates in synchronization with said rotating work and has a plurality of laser light passage areas, and a bonding mask disposed below said rotating mask. A laser processing method for a rotating body, wherein the irradiation of the laser beam is performed via an image lens. 3. A laser processing for irradiating a laser beam to a plurality of processing portions of a workpiece rotated by a rotation driving mechanism or a plurality of processing portions of a plurality of workpieces rotating by a rotation driving mechanism. An apparatus, comprising: a rotating mask having a plurality of laser light passage areas defining a beam pattern for irradiating a portion to be processed of the work, on a laser light incident side with respect to the work; Is a one-to-one correspondence with a plurality of processed parts of the work or a plurality of processed parts of the work.
The synchronization between the rotation of the rotary drive mechanism and the rotation of the rotary mask is performed so that the laser light that has passed through a certain laser light passage area is irradiated to the corresponding workpiece. A laser processing apparatus for a rotating body, comprising a synchronous drive unit. 4. The laser processing apparatus according to claim 3, wherein the laser light passage area is a pinhole, and an image of the pinhole is provided between the laser light passing through the pinhole and the work. A laser processing apparatus for a rotating body, wherein an image forming lens for forming an image on a portion to be processed is arranged. 5. The laser processing apparatus according to claim 3, wherein a pulsed laser beam is used as the laser beam, and a portion to be processed of the work is irradiated with one laser beam per rotation of the rotary table. A laser processing apparatus for a rotating body, characterized in that: 6. A laser processing apparatus for a rotating body according to claim 5, wherein a YAG pulse laser oscillator is used as a source of said pulsed laser light. 7. A laser processing apparatus according to claim 6, wherein a rotation sensor for detecting a rotation amount is provided in a rotation driving source of said rotation mask, and a detection signal from said rotation sensor is used as said Y signal.
By using the laser pulse as a laser oscillation trigger signal of an AG pulse laser oscillator, a laser beam is emitted when a laser beam passage area of the rotary mask reaches a position overlapping a portion to be processed of the work. Laser processing equipment for rotating bodies. 8. A laser processing apparatus according to claim 3, wherein said synchronous drive means includes a first gear provided on a rotation shaft of said rotary mask and a second gear provided on a rotation shaft of said rotation drive mechanism. A third gear is interposed between the first gear and the second gear, and the first gear and the second gear rotate in the same rotational direction at a ratio of 1: 1. A laser processing apparatus for a rotating body, which is realized by selecting the following. 9. The laser processing apparatus according to claim 3, wherein a radius r1 from the rotation center of the rotary mask to the laser light passage area and a radius r2 from the rotation center of the workpiece to the processing portion. If r2 is different,
The synchronous driving means includes a third gear interposed between a first gear provided on a rotation shaft of the rotary mask and a second gear provided on a rotation shaft of the rotation driving mechanism, and Is rotated, the distance L between the rotation center of the rotary mask and the rotation center of the work is set to a predetermined value, and the image forming ratio is set to a predetermined value. A laser processing apparatus for a rotating body, wherein the laser processing apparatus is realized by rotating the same number in the same direction.