JP5417586B2 - Laser processing apparatus and laser processing method - Google Patents

Description

  The present invention relates to a laser processing apparatus and a laser processing method for drilling a workpiece by irradiating a laser beam, and more particularly to a laser processing apparatus and a laser processing method for drilling a sheet-shaped workpiece or a hollow workpiece.

Conventionally, a method of drilling a hollow extruded material using a laser beam has been studied. In drilling with laser light, drilling is performed by concentrating energy only at the focal position of the beam. For this reason, when laser light is applied to the peripheral wall of the cylindrical material, only the peripheral wall has a perforating action, and the peripheral wall on the opposite side does not have a perforating action, which is suitable for perforating the peripheral wall of the cylindrical material.
In addition, since there is a tendency for laser drilled debris to enter the hollow part during drilling, as a method for suppressing or preventing this, gas is introduced into the hollow part through the gas introduction pipe, and the atmospheric pressure in the hollow part is increased to atmospheric pressure or higher. It is known to increase to a predetermined pressure. In this internal pressure state, when puncturing by irradiating laser light to the scheduled drilling position of the peripheral wall of the hollow extruded material, as soon as the drilling is performed, an air flow from the inside of the hollow portion to the outside is caused by the pressure difference inside and outside the extruded material hollow portion, The action of the airflow suppresses or prevents the penetration of perforated debris into the hollow portion (see, for example, Patent Document 1).

  However, if the hole is a small hole with a diameter of about 1 mm or less, it can be drilled by the above method. Will be blown out. When the outer periphery of a hole having a diameter of about 10 mm is continuously melted with a laser beam, arc-shaped grooves are opened, and the momentum of the gas ejected from the inside to the outside gradually decreases.

  Also, unlike a hollow metal body such as aluminum, when a resin hollow molded product molded by blow molding or the like is drilled with a laser beam, smoke with finer particles is generated instead of the drilled debris by the laser beam. . In a resin hollow molded product used in food containers, a fuel tank, an ink cartridge, and the like, it is necessary to prevent smoke generated during drilling by laser light from entering the resin hollow molded product.

  FIG. 8A shows an external perspective view of a resin hollow molded product (hollow body workpiece) 50 that is a hollow body workpiece that has been drilled by a conventional drill or a drilling method using laser light. The resin hollow molded product 50 has a box shape with one surface as an inclined surface, and is provided with a mouth 51 through which a liquid such as a beverage is taken in and out. When blow molding is performed, gas is introduced from the mouth 51 to expand the inside.

FIG. 8B is an external perspective view of a state in which the resin hollow molded product 50 is laid down sideways, and shows a state after a hole 52 is drilled in the center of the upper surface. Since the hollow resin molded product 50 is thin and is made of resin, there is a problem that it cannot be perforated well by a processing method in which a pressing force is applied from above such as a drill, and a problem that chips as cutting waste enter the hollow body. there were.
Even in the drilling method using laser light, there is a problem that smoke during drilling enters the hollow body.

JP-A-5-305469 (FIG. 1)

The present invention has been made to solve such problems, and as a drilling method, when a workpiece is drilled with a laser beam, the first task is to stably drill the hole with a laser beam. A second problem is to stably discharge gas and smoke generated when a workpiece is drilled with laser light.
In particular, the present invention has a third problem of stably drilling holes with laser light when a blow molded resin hollow molded product or the like is drilled with laser light. The fourth problem is to prevent the smoke generated when the holes are perforated with laser light from entering the hollow portion.

The present invention comprises laser means, assist gas delivery means, smoke exhaustion means, and pressurized gas delivery means for delivering pressurized gas to the hollow work, and the laser light is emitted to the hollow work. A laser processing apparatus for irradiating and punching , wherein a pressurized gas injection hole for sending the pressurized gas to a hollow portion is formed in advance in the hollow workpiece, and the laser beam of the hollow workpiece is formed. transmits the assist gas in the assist gas delivery means to the irradiation side, the pressurized gas is delivered by the pressurized gas delivery means in the hollow portion of the hollow body work, the said pressurized gas delivery pressure to said hollow body work with drilling by irradiating a laser beam to the hollow body work while greater than the assist gas delivery pressure, in the flue gas section, the assist gas delivery primarily in the laser beam irradiation side of the hollow body work The smoke generated during drilling is configured such that the flue gas.

  With this configuration, at the moment when the hole is opened in the workpiece, the pressurized gas overflows from the hole opened in the workpiece, and the assist gas is discharged to the outside together with the smoke generated at the time of drilling. As a result, the assist gas does not push down the melted portion at the peripheral edge of the workpiece during drilling. Further, for example, when the arc-shaped groove hole is continuously melted with a laser beam in order to open a hole having a diameter of about 10 mm or more, the remaining portion at the center surrounded by the groove hole is lifted by the pressurized gas. Will open stably.

  When punching a blow molded resin hollow molded product with laser light, the assist gas and smoke generated during drilling are prevented from entering the hollow part by the pressurized gas overflowing from the open hole. , Exhausted outside by smoke exhaustion means.

  According to the present invention, when drilling a workpiece with a laser beam as a drilling method, the hole can be stably drilled with a laser beam, and the assist gas and smoke generated when the workpiece is drilled with a laser beam can be stabilized. Can be discharged. In particular, when a blow molded resin hollow molded product or the like is drilled with laser light, the holes can be stably drilled with laser light. Further, it is possible to prevent the smoke generated when the assist gas or the hollow resin molded product is perforated with laser light from entering the hollow portion.

Sectional drawing of the laser processing apparatus which concerns on Embodiment 1 of this invention. The top view which showed the laser processing apparatus and workpiece | work which concern on Embodiment 1 of this invention. The flowchart of the laser processing method which concerns on Embodiment 1 of this invention. The flowchart of the laser processing method which concerns on Embodiment 2 of this invention. Sectional drawing which shows the drilling state of the laser processing apparatus which concerns on Embodiment 2 of this invention. Sectional drawing which shows the drilling state by the other Example of the laser processing apparatus which concerns on Embodiment 2 of this invention. Sectional drawing of the laser processing apparatus which concerns on Embodiment 3 of this invention. (A) External perspective view of a resin hollow molded product that is a conventional drilling target (B) External perspective view when the resin hollow molded product that is a conventional drilling target is drilled.

(Embodiment 1)
Embodiment 1 of the present invention will be described. FIG. 1 shows a cross-sectional view of a laser processing apparatus 1 according to the first embodiment. A laser means 10 guides laser light from a laser oscillator (not shown) directly below the laser head 11 by a reflection lens (not shown) and irradiates the surface of the hollow work 50 with the laser light to punch holes 52. I have to.

  An assist gas nozzle 12 is provided below the laser head 11, and assist gas from an assist gas delivery means 20 (not shown) is blown directly under the laser head 11 via a pressure adjusting valve 21. Reference numeral 13 denotes a laser head hood that shields the space near the laser head 11 from the outside air and is generated by a perforating operation using assist gas or laser light that accumulates inside the laser head hood 13 from the smoke exhaust port 14 provided on the side surface. The smoke is discharged by a smoke exhausting means 40 (not shown).

  50 is a hollow body work, and the port 51 is used as a pressurized gas intake port. Pressurized gas is delivered from the pressurized gas intake 51 by a pressurized gas delivery means (not shown). The pressure P1 of the pressurized gas is made larger than the assist gas delivery pressure P2 by a pressure adjusting valve for pressurized gas (not shown). At the smoke outlet 14 of the laser head hood 13, the discharge pressure P3 is made smaller than the assist gas delivery pressure P2. As described above, the pressure in the vicinity of the laser head 11 is reduced from P1 to P3 such that P1> P2> P3, so that the smoke generated by the perforation work by the pressurized gas, the assist gas, and the laser beam is reduced. It flows stably as shown by the arrows in the figure.

  As described above, the laser head hood 13 is disposed close to the workpiece so as to shield the space near the laser head 11 from the outside air. Therefore, for example, when the outer periphery of a hole having a diameter of about 10 mm is continuously melted with a laser beam, the arc-shaped groove hole is sequentially enlarged. However, the pressurized gas is accumulated in the laser head hood 13 and from the smoke exhaust port 14. Discharged. The pressurized gas is not released to the outside at once. If the magnitude relationship of the pressure in the vicinity of the laser head 11 is maintained as P1> P2> P3, there is an advantage that an operation for increasing the air pressure in the hollow portion to a predetermined pressure is not required as the size of the slot increases. There is.

When the mouth 51 is not open, a needle-like needle may be pierced to make a small hole and pressurized gas may be inserted, and the hole 51 may be closed when the drilling operation is completed. Moreover, about what provided the rubber part in the hollow body workpiece | work, you may make it pressurize gas by inserting the needle-like needle into the said rubber part.
FIG. 2 shows a plan view when the laser processing apparatus according to Embodiment 1 is arranged on a workpiece. In FIG. 2, for easy understanding, the assist gas delivery means 20 is arranged on the right side of the laser means 10, and the smoke exhaust means 40 is arranged on the left side so that the assist gas passes from the assist gas delivery means 20 directly below the laser head 11 of the laser means 10. The state of being discharged from the laser head hood 13 by the smoke exhausting means 40 is indicated by arrows. For example, in order to open a hole having a size of about 10 mm, the laser head 11 is turned as indicated by an arrow A. At this time, the laser means 10, the assist gas delivery means 20, and the smoke exhausting means 40 are moved together with the turning operation of the arrow A of the laser head 11. Reference numeral 50 denotes a hollow body work, and a pressurized gas is delivered from a pressurized gas intake 51 by a pressurized gas delivery means (not shown).

  FIG. 3 shows a flowchart of an operation method of the laser processing apparatus 1 according to the first embodiment. In step S <b> 1, a pressurized gas, specifically compressed air, is sent to the hollow portion of the hollow workpiece 50. Next, in step S <b> 2, assist gas is sent from the assist gas nozzle 12 to the surface of the hollow body work 50. When the pressurized gas delivery pressure is greater than the assist gas delivery pressure, the hollow body workpiece 50 is irradiated with laser light to be perforated (step S3). Simultaneously with the irradiation of the laser beam, the smoke generated by the assist gas and the drilling operation is discharged from the smoke exhaust port 14 of the laser head hood 13 using the smoke exhaust means 40. It should be noted that the pressurized gas enters the laser head hood 13 from the moment when the hole 52 is opened in the drilling operation, but the pressurized gas that has entered also is discharged.

  By performing the above operation method, the hole 52 can be stably drilled without bringing a tool into contact with the surface of the hollow work 50. Moreover, since the pressurized gas is filled in the hollow part of the hollow body work 50 and the pressurized gas delivery pressure is higher than the assist gas delivery pressure, the hollow part of the hollow body work 50 is generated by the assist gas or the drilling operation. The effect that smoke does not enter is obtained.

In the above description, in order to facilitate understanding, the case where the laser light irradiation position is moved on the circumference and a hole having a size of about 10 mm is formed is described. However, the present invention moves the laser light irradiation position. Can also be applied to the case where a laser beam irradiation position is slightly moved to make a hole slightly larger than the beam diameter of the laser beam, the effect of stably drilling the hole as described above, The effect that the smoke at the time of drilling can be discharged in a predetermined direction is obtained.
(Embodiment 2)
A second embodiment will be described. In the second embodiment, control for increasing the suction force of the smoke exhausting means 40 is performed only for a specific timing period, and the portion cut out immediately below the laser head 11 by the drilling operation is automatically discharged from the vicinity of the laser head 11. .

  The structure of the laser processing apparatus 2 of the second embodiment is basically the same as that of the first embodiment. The operation method of the second embodiment will be described with reference to the flowchart of FIG. The operation from step S1 to step S4 is basically the same as that of the flowchart of FIG. 3 already described, except that step S1 and step S2 are performed simultaneously. When step S1 and step S2 are performed simultaneously, there is an advantage that the working time can be shortened.

  What is new in the flowchart of FIG. 4 is that the operation of step S5 is added. In step S5, the suction force of the smoke exhausting means 40 is increased during the timing period before and after the portion 53 cut immediately below the laser head 11 by the drilling operation is cut. As a result, the portion 53 cut out immediately below the laser head 11 by the drilling operation can be discharged and removed from the vicinity of the laser head 11.

  FIG. 5 shows the operation of step S5, that is, the portion 53 cut from the hollow work 50 directly under the laser head 11 by the drilling operation, and the assist gas and the smoke are discharged from the portion directly under the laser head 11 by the suction force of the smoke discharging means 40. The movement is shown schematically. Since the portion 53 cut out from the hollow work 50 is made of resin and is light, it floats upward due to the pressure difference and moves as indicated by an imaginary line 53 ′ in FIG. 5 to be discharged from the smoke outlet 14 of the laser head hood. Is done.

  If the suction force of the smoke exhausting means 40 is increased and the delivery pressure of the pressurized gas delivery means 30 is instantaneously increased, the portion 53 cut out immediately below the laser head 11 can be pushed out. As described above, according to the present invention, not only the stable drilling is performed, but also the assist gas or smoke is not put into the hollow part of the hollow work, and further, the part cut out from the hollow work is automatically taken out from the vicinity of the laser head. be able to. If the hole is larger than twice the beam diameter of the laser beam, a part of the material is not melted and is cut out as a small piece. According to the present invention, the cut out piece is automatically cut from the vicinity of the laser head. The effect that it can be taken out is obtained.

FIG. 6 shows a modification of the laser processing apparatus according to Embodiment 2 of the present invention, in which the laser beam irradiation direction of the laser processing apparatus is set to the horizontal direction. As a result, the portion 53 ′ cut out from the hollow body workpiece falls downward due to its own weight, so that it can be easily taken out from the vicinity of the laser head. Note that if the fusing start position and fusing end position by laser light are the upper part of the cut out piece as shown in FIG. 6, the lower part of the cut out piece by the pressurized gas is inclined in a direction that can be easily discharged, so that the weight falls stably. .
(Embodiment 3)
Embodiment 3 of the present invention will be described. The third embodiment is characterized in that the same gas is used for the pressurized gas and the assist gas. Since the same gas is used for the pressurized gas and the assist gas, as shown in FIG. 7, the assist gas is also sent from the assist gas delivery means 20 to the hollow portion of the hollow work 50 through the pressure adjusting valve 22. . By the first pressure adjusting valve 22, the assist gas is delivered at the first pressure P <b> 1 so as to serve as a pressurized gas in the hollow body work 50. Then, the assist gas delivered at the first pressure P1 by the pressure adjusting valve 22 passes through the second pressure adjusting valve 23 to the laser head 11 of the laser means 10 at a pressure P2 smaller than the first pressure P1. Sending out. Since the gas delivery means is shared, there is an advantage that the apparatus can be simplified.

The operation of the third embodiment is basically the same as the operation of FIG. 3 shown in the first embodiment. In addition, you may perforate by the operation | movement of FIG. In that case, the cut portion can be automatically taken out from the vicinity of the laser head.
In the first, second, and third embodiments, the case where the workpiece to be drilled is a hollow workpiece has been described. However, the workpiece is not limited to the drilling of a hollow workpiece, but can be used for punching a sheet-like workpiece such as a plastic sheet. Can do. In addition, the workpiece that is an object to be laser processed may be, for example, a plate material or a thin cylindrical workpiece, and the material may be not only a resin but also a metal such as aluminum or iron.

  INDUSTRIAL APPLICABILITY The present invention can be used for drilling a resin hollow molded product such as a food container, a fuel tank, or an ink cartridge. Moreover, not only the drilling work of the hollow work but also the punching work of a sheet-like work such as a plastic sheet can be used.

DESCRIPTION OF SYMBOLS 10 Laser means 11 Laser head 12 Assist gas nozzle 13 Laser head hood 14 Smoke exhaust port 20 Assist gas delivery means 21, 22, 23 Pressure adjusting valve 30 Pressurized gas delivery means 40 Smoke exhaust means 50 Hollow body work 51 Pressurized gas collection Slot 52 holes

Claims (2)

Laser means;
Assist gas delivery means;
Smoke removal means;
A pressurized gas delivery means for delivering pressurized gas to the hollow body workpiece,
A laser processing apparatus for piercing by irradiating the hollow workpiece with a laser beam,
In the hollow body work, a pressurized gas injection hole for sending the pressurized gas to the hollow part is formed in advance , and the assist gas is delivered to the laser beam irradiation side of the hollow body work by the assist gas delivery means. The hollow body is delivered in a state where pressurized gas is delivered by the pressurized gas delivery means to the hollow portion of the hollow body work, and the pressurized gas delivery pressure for the hollow body work is greater than the assist gas delivery pressure. While irradiating the workpiece with laser light and drilling,
The laser processing apparatus, wherein the smoke exhausting means is configured to exhaust the assist gas delivered to the laser beam irradiation side of the hollow body work and the smoke generated during drilling. Laser means;
Assist gas delivery means;
Smoke removal means;
A pressurized gas delivery means for delivering pressurized gas to a hollow body workpiece that is a resin hollow molded product ,
A laser processing apparatus for piercing by irradiating the hollow workpiece with a laser beam,
In the hollow body work, a pressurized gas injection hole for sending the pressurized gas to the hollow part is formed in advance , and the assist gas is delivered to the laser beam irradiation side of the hollow body work by the assist gas delivery means. The hollow body is delivered in a state where pressurized gas is delivered by the pressurized gas delivery means to the hollow portion of the hollow body work, and the pressurized gas delivery pressure for the hollow body work is greater than the assist gas delivery pressure. The workpiece is perforated by irradiating it with laser light, and the smoke exhausting means is configured to exhaust the assist gas delivered mainly to the laser light irradiation side of the hollow body workpiece and the smoke generated during perforation. Laser processing equipment.

Images