JP2012187606A - Laser beam machining device and laser beam machining method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a laser beam machining device which can stably make the center of the opening in a machining nozzle and the optical axis of a laser beam eccentric at a high speed and at high precision even in the case a temperature change is generated.SOLUTION: The laser beam machining device includes a control part (50), in the case a laser beam is emitted from a machining head, simultaneously, a machining gas is blown out, and a workpiece is subjected to cutting, which controls the amount of eccentricity between the center of a machining nozzle and the center of the optical axis of the laser beam by bi-axially moving a machining lens condensing the laser beam to the optical axis of the laser beam in a vertical plane. The control part performs the control of the amount of eccentricity by feedback-controlling the position of the machining lens so that measured positional information is made into the objective position, and further, compensates the positional information measured during the practice of the feedback control on the basis of the datum point positional information measured at a position which should be a datum point before the practice of the feedback control.

Description

  The present invention relates to a laser processing apparatus and a laser processing method for emitting a laser beam from a processing head and simultaneously ejecting a processing gas to perform cutting processing.

  In conventional laser cutting using a processing gas, the center of the processing nozzle that ejects the processing gas and the optical axis center of the laser beam are decentered, and the optical axis of the laser beam is moved in the direction of processing from the center of the processing nozzle opening. It is widely known to be offset. As a result, the flow direction of the melt and the sputter adhesion area are controlled, and high-quality cutting is possible.

  As a method of decentering the opening center of the processing nozzle and the optical axis of the laser beam, there are the following methods. For example, the processing nozzle is moved to an arbitrary position on a plane orthogonal to the laser beam by using two drive motors as driving devices, or an arbitrary surface on a curved surface with the laser beam optical axis as a normal line. A method of moving to a position is disclosed (for example, see Patent Document 1).

  As another method, the eccentric amount of the opening center of the machining nozzle with respect to the laser beam optical axis is set in advance by the material of the workpiece to be machined, the plate thickness, etc., and the machining nozzle is rotated together with the housing by the drive motor. A method for maintaining the direction and the eccentric direction is disclosed (for example, see Patent Document 2). Further, Patent Document 2 discloses a method in which the eccentric direction and the eccentric amount are detected by an encoder provided in a drive motor, and the machining head main body is scan-controlled by the NC.

  In addition to such a method, a method is also disclosed in which a mirror and a processing lens are swung by a crank mechanism using a small motor (see, for example, Patent Document 3).

Japanese Patent No. 3287112 Japanese Patent Laid-Open No. 11-90663 JP-A-5-169285

However, the prior art has the following problems.
The processing head main body in Patent Document 1 and Patent Document 2 is in a state where the pressure of the processing gas is constantly applied. Therefore, both a structure for moving while keeping airtightness and a pressure-resistant structure against gas pressure are required, and there is a problem that the structure of the processing head main body becomes complicated and the weight increases.

  Furthermore, in the case of a laser processing apparatus that scans the processing head body, if the weight of the processing head body increases, a load is applied to the scanning mechanism of the processing head body, the scanning speed decreases, and the scanning accuracy deteriorates. was there.

  Further, in Patent Document 3, a mechanical mechanism such as a ball screw, a spur gear (spur gear), or a crank mechanism is required to convert the rotational motion of the drive motor into a linear motion. In the mechanism, there is a problem that it is difficult to avoid backlash and the positioning accuracy is limited.

  Furthermore, neither direct measurement of the lens position or nozzle position nor position control by feedback of the lens position is disclosed in any patent document.

  The present invention has been made to solve the above-described problems. Even when a temperature change occurs due to heat generation of the moving mechanism, absorption of laser light, or the like, the present invention can be stably and rapidly performed with high accuracy. An object of the present invention is to obtain a laser processing apparatus and a laser processing method capable of decentering the opening center of the processing nozzle and the optical axis of the laser beam.

  A laser processing apparatus according to the present invention includes a laser oscillator that oscillates a laser beam, a gas supply unit that supplies a processing gas, and a laser beam oscillated from the laser oscillator is emitted from a processing nozzle and supplied from the gas supply unit. By ejecting the processed gas from the processing nozzle, the beam output of the laser beam oscillated from the laser oscillator based on the processing head body for cutting the workpiece to be processed and the type and processing conditions of the workpiece A control unit that controls the amount of processing gas supplied from the gas supply unit and controls the amount of eccentricity that offsets the optical axis of the laser beam emitted from the processing nozzle with respect to the opening center of the processing nozzle. The machining head body focuses the laser beam emitted from the laser oscillator toward the workpiece. A processing lens, a magnetic movement mechanism that moves the processing lens in two axes in a plane or curved surface perpendicular to the optical axis of the laser beam by magnetic driving by a plurality of electromagnets, and a position detector that measures positional information of the processing lens The control unit performs feedback control of the current values of the plurality of electromagnets so that the position information measured by the position detector becomes the target position, and moves the processing lens to the target position by two axes to perform eccentricity. In addition to performing quantity control, the position information measured by the position detector during the feedback control is compensated based on the origin position information measured by the position detector at the position that should originally be the origin before executing the feedback control. To do.

  Further, the laser processing method according to the present invention is a process for condensing a laser beam toward a work when a work gas is ejected at the same time as a laser beam is emitted from the work head, and the work to be processed is cut. Laser processing that controls the amount of eccentricity between the center of the processing nozzle that ejects processing gas and the center of the optical axis of the laser beam by moving the lens in two planes within a plane or curved surface perpendicular to the optical axis of the laser beam The method includes a step of measuring the position that should be the original origin of the processing lens as origin position information before execution of the eccentricity control, and position information of the processing lens measured during execution of the eccentricity control. Compensating based on the origin position information and a step of controlling the eccentricity so that the compensated position information becomes the target position.

  According to the laser processing apparatus and the laser processing method of the present invention, even when there is a change in the measurement value due to the temperature rise of the distance measurement system due to the current flowing in the electromagnet or the laser light absorbed by the lens. Measure the position that should originally be the origin in the temperature state at the time of actual processing, and correct the position of the processing lens based on this measurement result, thereby generating heat of the moving mechanism, absorption of laser light, etc. Even when a temperature change occurs due to the cause, it is possible to obtain a laser processing apparatus and a laser processing method capable of decentering the opening center of the processing nozzle and the optical axis of the laser beam stably with high speed and high accuracy. .

It is a block diagram which shows the laser processing apparatus by Embodiment 1 of this invention. It is sectional drawing which shows the usage condition of the process head main body of FIG. 1, the process nozzle, and the workpiece | work by Embodiment 1 of this invention. It is sectional drawing which shows another usage condition of the processing head main body of FIG. 1, the processing nozzle, and the workpiece | work by Embodiment 1 of this invention. It is a block diagram which shows the magnetic moving mechanism of FIG. 2 by Embodiment 1 of this invention. It is a block diagram which shows the usage condition of the magnetic moving mechanism of FIG. 2 by Embodiment 1 of this invention. It is another block diagram which shows the magnetic movement mechanism of previous FIG. 2 by Embodiment 1 of this invention. It is a block diagram which shows the magnetic moving mechanism of the laser processing apparatus by Embodiment 2 of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the drawings, the same or equivalent members and parts will be described with the same reference numerals. In each figure, the surface to be cut is defined as the xy plane, and the direction perpendicular thereto is defined as the z axis.

Embodiment 1 FIG.
FIG. 1 is a block diagram showing a laser processing apparatus according to Embodiment 1 of the present invention. The laser processing apparatus 100 according to the first embodiment includes a laser oscillator 10, a laser beam transmission system 20, a processing head body 30, a gas supply device 40 (gas cylinder 40), and a control device 50.

  The laser beam transmission system 20 transmits the laser beam 11 oscillated from the laser oscillator 10 into the machining head main body 30 via a plurality of mirrors 21. A processing nozzle 36 is attached to the processing head main body 30.

  Further, a processing gas introduction pipe 41 is connected to the gas cylinder 40, and the processing gas 43 is supplied to the processing nozzle 36 through the processing gas introduction pipe 41. A gas valve 42 for adjusting the supply amount of the processing gas 43 is provided in the middle of the processing gas introduction pipe 41.

  The control device 50 controls the supply amount of the processing gas 43 by the gas valve 42, the beam output of the laser oscillator 10, and the driving of the processing head main body 30 based on the type of workpiece 1 and the processing conditions.

  Here, the workpiece 1 is made of various materials such as metal, resin, ceramic, glass, and crystal. In particular, when the workpiece 1 is a metal, the processing gas 43 generates metal oxidation heat, and the cutting can be performed at a higher speed.

  FIG. 2 is a cross-sectional view showing how the machining head body 30, the machining nozzle 36, and the workpiece 1 of FIG. 1 according to Embodiment 1 of the present invention are used. More specifically, a detailed configuration at the time of piercing (processing for forming a through hole at a cutting start position) is shown.

  The processing head main body 30 includes a processing lens 31, a processing lens holding mechanism 32, a magnetic movement mechanism 33, a partition plate 34, and a fixed base 35. The processing lens 31 is arranged as a circle on the central axis inside the processing head body 30 during piercing. The processing lens holding mechanism 32 surrounds the processing lens 31 and holds the peripheral edge.

  The magnetic moving mechanism 33 is provided around the processing lens 31 and moves the processing lens holding mechanism 32 in a biaxial linear manner in a plane perpendicular to the optical axis 22a of the laser beam 22 (in the XY plane). The lens 31 is moved. The partition plate 34 is provided to face the processing lens 31 and prevents the processing gas 43 from entering the processing head main body 30 through the processing nozzle 36. The fixed base 35 fixes the magnetic movement mechanism 33, and details of the magnetic movement mechanism 33 will be described later.

In the processing nozzle 36, the tip end of the processing gas introduction pipe 41 faces the inside, and an opening 37 facing the workpiece 1 is formed at the tip. Then, the processing gas 43 is supplied from the gas cylinder 40 to the processing nozzle 36 through the processing gas introduction pipe 41. Here, for example, the gas cylinder 40 contains oxygen (O ₂ ) gas or nitrogen (N ₂ ) gas. In addition, a gas valve 42 for adjusting the supply amount of the processing gas 43 is attached to the processing gas introduction pipe 41, and the supply amount can be adjusted by the control device 50. Instead of the gas cylinder 40, a compressor that supplies high-pressure air may be used.

  The control device 50 is connected to the gas valve 42, the laser oscillator 10, and the magnetic movement mechanism 33. Based on the type of workpiece and processing conditions, the control device 50 supplies the processing gas 43, the beam output of the laser oscillator 10, and the processing lens. The position of 31 is controlled. Here, the control device 50 measures the distance between the position detector 331 fixed to the fixed base 35 and the position detector target 332 fixed to the processing lens holding mechanism 32 with the position detector 331, thereby processing. The position of the lens 31 is obtained.

  In such a laser processing apparatus 100 according to the first embodiment, the laser beam 22 oscillated from the laser oscillator 10 is guided into the processing head main body 30 via the laser beam transmission system 20. Further, in the machining head main body 30, the introduced laser beam 22 is collected by the machining lens 31 and irradiated onto the workpiece 1 through the opening 37 at the tip of the machining nozzle 36.

  The laser processing apparatus 100 shown in FIG. 2 shows a piercing process. For this reason, the workpiece 1 is stationary, and the optical axis 22 a of the laser beam 22 coincides with the center of the processing lens 31 and the opening center 37 a of the opening 37 of the processing nozzle 36.

  On the other hand, the processing gas 43 introduced from the processing gas introduction pipe 41 to the processing nozzle 36 is ejected from the opening 37 of the processing nozzle 36 onto the workpiece 1. In the workpiece 1, the material is heated, melted and blown off by the laser beam 22 and the processing gas 43. By this operation, the piercing hole 2 is formed, and a through hole serving as a cutting start position is formed.

  FIG. 3 is a cross-sectional view illustrating another usage mode of the processing head main body, the processing nozzle, and the workpiece of FIG. 1 according to the first embodiment of the present invention. More specifically, a detailed configuration at the time of the cutting process is shown, and the cutting groove 3 is formed in a portion of the workpiece 1 where the laser beam 22 is scanned, and the cutting process is performed.

  Here, FIG. 3 shows a case where the processing lens 31 is moved by the magnetic movement mechanism 33, and the processing lens central axis 31a is moved in the direction of reference numeral D1 in FIG. 3 with respect to the optical axis 22a. In this case, the laser beam 22 is bent in the direction of the processing lens central axis 31a and collected on the processing lens central axis 31a. Since the laser beam 22 is bent, the position of the laser beam 22 at the opening 37 portion of the processing nozzle 36 is away from the opening center 37a.

  For example, as shown in FIG. 3, when the position of the laser beam 22 is decentered in the processing progress direction with respect to the opening center 37a, the processing gas 43 and the melted material are formed after the cutting groove 3 is formed. 4 flows smoothly along the cutting groove 3.

  Here, the magnetic movement mechanism 33 is a combination of mechanisms that perform biaxial linear movement, and is controlled to an arbitrary position by the control device 50 based on the type of the workpiece 1 and the machining conditions. Further, the amount of eccentricity of the laser beam 22 is selected according to parameters such as the processing material of the workpiece 1, the thickness, the type of the processing gas 43, the spraying amount, the processing speed, and the intensity of the laser beam 22.

  FIG. 4 is a configuration diagram showing the magnetic movement mechanism 33 of FIG. 2 according to Embodiment 1 of the present invention. More specifically, the configuration of the magnetic movement mechanism 33 at the time of piercing is represented by an XY plane. The processing lens holding mechanism 32 that holds the processing lens 31 includes a first actuator 330 (1), a second actuator 330 (2), a third actuator 330 (3), and a fourth actuator 330 (4). It is attached from four directions.

  The first actuator 330 (1) and the second actuator 330 (2) provided to face the first actuator 330 (1) correspond to an actuator that moves the processing lens 31 in the x direction. . Further, the third actuator 330 (3) and the fourth actuator 330 (4) provided to face the third actuator 330 (3) are actuators that move the processing lens 31 in the y direction. Equivalent to.

  Further, each of the first actuator 330 (1) to the fourth actuator 330 (4) includes an electromagnet 330 a fixed to the rectangular fixed base 35, and the processing lens holding mechanism 32 facing each electromagnet 330 a. The magnetic target 330b is fixed. Here, the position of the processing lens holding mechanism 32 is defined in the z direction by a static pressure guide such as air, oil, magnetic fluid, or an elastic hinge guide constituted by a leaf spring or the like.

  Further, the x-direction position detector 331x is fixed to the fixed base 35, and the x-direction position detector target 332x is fixed to the processing lens holding mechanism 32 so as to face the x-direction position detector 331x. Then, the x-direction position detector 331x measures the distance to the x-direction position detector target 332x.

  Similarly, the y-direction position detector 331y is fixed to the fixed base 35, and the y-direction position detector target 332y is fixed to the processing lens holding mechanism 32 so as to be opposed thereto. Then, the y-direction position detector 331y measures the distance to the y-direction position detector target 332y.

  FIG. 4 shows the time of piercing as shown in FIG. 2, and the control device 50 causes each of the first actuators 330 so that the optical axis 22 a of the processing lens 31 passes through the center of the laser beam 22. (1)-The electric current which flows into each electromagnet 330a of the 4th actuator 330 (4) is controlled.

  At the same time, the x-direction position detector 331x measures the distance to the x-direction position detector target 332x, and the control device 50 reads the x-direction position information from the x-direction position detector 331x. Then, the control device 50 performs feedback control of the lens position so that the difference between the set value (target value) and the position information (feedback value) becomes small.

  On the other hand, FIG. 5 is a configuration diagram showing one usage mode of the magnetic movement mechanism 33 of FIG. 2 according to the first embodiment of the present invention. More specifically, the configuration of the magnetic movement mechanism 33 at the time of cutting is represented by an XY plane. As shown in FIG. 3, the machining lens central axis 31a is decentered in the X direction from the optical axis 22a. Shows the state.

  Here, based on the set value of the position to be decentered in the x direction, the control device 50 increases the current flowing through the electromagnet 330a of the first actuator 330 (1) and draws the magnetic target 330b to the electromagnet 330a. Thus, the processing lens holding mechanism 32 integrated with the magnetic target 330b is pulled toward the x minus side, and the processing lens 31 is moved in the x minus direction.

  At the same time, the x-direction position detector 331x measures the distance to the x-direction position detector target 332x, and the control device 50 reads the x-direction position information from the x-direction position detector 331x. The control device 50 performs feedback control of the actuator so that the difference between the set value (target value) and the position information (feedback value) becomes small.

  This example is an example in the case of moving in the X direction, and the control device 50 changes the value of the current flowing through each electromagnet 330a of the first actuator 330 (1) to the fourth actuator 330 (4). The processing lens holding mechanism 32 can be moved to an arbitrary position on the xy plane as long as the electromagnets 330a and the magnetic target 330b do not contact each other.

  That is, in FIG. 5, the case of moving in the X direction is illustrated, but the control device 50 also uses the y direction position detector 331y and the y direction position detector target 332y for the Y direction. Can be obtained. As a result, the control device 50 can move the processing lens 31 to an arbitrary position on the xy plane.

  Next, a specific description will be given of a method in which the control device 50 performs position compensation with respect to a temperature change based on position information acquired through the position detector. The electromagnet 330a generates heat when an electric current is passed, and this heat increases the temperature of the x-direction position detector 331x and the y-direction position detector 331y via the fixed base 35.

  Further, part of the energy of the laser beam 22 is absorbed by the processing lens 31 and converted into heat, and the temperatures of the x-direction position detector target 332x and the y-direction position detector target 332y are changed via the processing lens holding mechanism 32. Raise. Furthermore, the heat generated by the electromagnet 330a and the absorption of the energy of the laser beam 22 raises the temperature of the entire magnetic moving mechanism 33 in the contact portion and atmosphere.

  Due to these temperature rises, the measured values of the x-direction position detector 331x and the y-direction position detector 331y drift. As a result, accurate position information cannot be obtained, and the processing lens 31 cannot be moved to the target position.

  Therefore, the control device 50 in the laser processing apparatus 100 according to the first embodiment uses the x-direction position detector 331x and the y-direction position detector 331y in a state where an equal current is supplied to the four electromagnets 330a. The measured value is obtained as the origin position, and the position information measured after that is compensated.

  That is, this origin position corresponds to a position that should originally be the origin, and a measured value by the position detector is a result of temperature drift, but is an origin position with reproducibility based on a constant output from the actuator.

  As a result, the position where the electric attractive forces of the four electromagnets 330a are balanced can always be set as the origin, so that the position information of the processing lens 31 can be corrected and the lens position can be accurately controlled. As a result, the processing lens 31 is moved at a high speed by the magnetic attraction generated by the current flowing through the electromagnet 330a, and is positioned with high accuracy by control based on accurate position information.

  Therefore, even when the magnetic movement mechanism 33 changes in temperature due to heat generated by the electromagnet 330a or absorption of the laser beam 22, the center of the processing nozzle 36 and the optical axis 22a of the laser beam 22 are eccentric with high speed and high accuracy. be able to. Thereby, the processing gas 43 and the melt 4 can flow smoothly along the cutting groove 3 by biasing the optical axis 22a of the laser beam 22 from the opening center 37a of the processing nozzle 36 in the processing progress direction. High quality cutting can be performed.

  In order to compensate the position information using the measured values of the x-direction position detector 331x and the y-direction position detector 331y as the origin position in a state where an equal current flows through the electromagnet 330a, the machining head main body 30 is subjected to acceleration motion. It is necessary to be in a state where no operation is performed. This is because when the machining head main body 30 is accelerating, a force other than the attractive force of the electromagnet 330a is applied to the machining lens holding mechanism 32, and the machining lens holding mechanism 32 is not held at the origin position. Because.

  Further, during the processing of irradiating the workpiece 1 with the laser beam 22, the position information of the processing lens holding mechanism 32 is controlled, so that the position information cannot be compensated. Therefore, the control device 50 compensates the position information when the laser processing apparatus 100 is in the processing operation, the laser processing head main body 30 is stopped, and the workpiece 1 is not irradiated with the laser beam 22. The time for compensating the position information varies depending on the machining shape and machining path, but can be arbitrarily set by the control device 50.

  As described above, according to the first embodiment, even when the measured value changes due to the temperature rise of the distance measuring system due to the current flowing through the electromagnet or the laser light absorbed by the lens, In the temperature state at the time of processing, the position of the processing lens is corrected based on the measurement result by measuring the position that should originally be the origin.

  As a result, even when a temperature change occurs due to heat generation of the moving mechanism, absorption of laser light, etc., the center of the opening of the machining nozzle and the optical axis of the laser beam are decentered stably and at high speed. A laser processing apparatus and a laser processing method that can perform the processing can be obtained.

  Specifically, by compensating the position information during the time when the laser processing head while the laser processing machine is performing the processing operation is stopped, it is possible to follow a constantly changing temperature environment. Furthermore, even if the magnetic movement mechanism changes in temperature due to heat generation of the magnet, absorption of laser light, etc., stable high speed and high precision machining can be realized.

  In the above-described first embodiment, the case where each of the position detector and the position detector target in the x direction and the y direction is one set has been described. However, the present invention is not limited to such a configuration. . FIG. 6 is another configuration diagram showing the magnetic movement mechanism 33 of FIG. 2 according to the first embodiment of the present invention.

  For example, in FIG. 6, the second x-direction position detector 333 x and the second x-direction position detector 331 x and the second x-direction position detector target 332 x are positioned symmetrically with respect to the processing lens holding mechanism 32. The x-direction position detector target 334x is arranged. By adopting such two sets of arrangements, more stable position information can be obtained by differential measurement of the x-direction position detector 331x and the second x-direction position detector 333x. The same applies to the y direction.

  Furthermore, if a position detector and a position detector target are added, it is possible to detect posture information such as torsion of the processing lens holding mechanism 32 and movement in the z direction.

  As the position detector, those using eddy current, those using electrostatic capacity, those using light reflection, those using sound waves, etc., depending on the moving range and position accuracy of the processing lens holding mechanism 32. Can be selected arbitrarily.

Embodiment 2. FIG.
In the second embodiment, a magnetic movement mechanism 33A further provided with a spring holding mechanism compared to the configuration of the first embodiment will be described. FIG. 7 is a configuration diagram showing a magnetic movement mechanism 33A of the laser processing apparatus 100 according to the second embodiment of the present invention.

  In the second embodiment, one end of the first leaf spring 336 is connected to each of the four corners of the rectangular processed lens holding mechanism 32A. In FIG. 7, one end of a second leaf spring 337 extending outward at a substantially right angle to the first leaf spring 336 is connected to the other end of each first leaf spring 336 extending in the vertical direction. Yes. The connecting portions of the first plate spring 336 and the second plate spring 337 facing each other are connected by a holding member 335. Further, the other end of the second leaf spring 337 is connected to the fixed base 35.

  The first leaf spring 336 and the second leaf spring 337 are wide in the z direction and thin in the x direction or the y direction. By such a spring mechanism, the processing lens holding mechanism 32A is restricted from moving in the z direction and can move in the xy plane perpendicular to the optical axis 22a of the laser beam 22.

  Here, the 1st leaf | plate spring 336 is produced by punching the thin plate of spring steel materials, such as stainless steel, phosphor bronze, beryllium copper, into a rectangular flat plate, for example. The second leaf spring 337 is made of the same material as the first leaf spring 336 and is formed in the same shape. Moreover, the holding member 335 is produced by forming a thick plate material such as aluminum into a rectangular flat plate, for example.

  The first leaf spring 336, the second leaf spring 337, and the holding member 335 constitute an elastic hinge that restricts the processing lens 31 from moving in the z direction that is the direction of the optical axis 22a.

  Further, the x-direction position detector 331x is fixed to the fixed base 35, and the x-direction position detector target 332x is fixed to the processing lens holding mechanism 32A so as to face the x-direction position detector 331x. Then, the x-direction position detector 331x measures the distance to the x-direction position detector target 332x.

  Similarly, the y-direction position detector 331y is fixed to the fixed base 35, and oppositely, the y-direction position detector target 332y is fixed to the processing lens holding mechanism 32A. Then, the y-direction position detector 331y measures the distance to the y-direction position detector target 332y. Other configurations are the same as those of the laser processing apparatus 100 of the first embodiment.

  FIG. 7 shows a state in which the processing lens 31 is moving in the x minus direction, as in FIG. 5 in the first embodiment. In this state, the control device 50 controls the current flowing through the electromagnets 330a of the first actuator 330 (1) and the second actuator 330 (2). As a result, the four first leaf springs 336 are bent in the xy plane, and the electromagnetic force of the first actuator 330 (1) and the second actuator 330 (2) and the elastic force of the first leaf spring 336 are obtained. The position of the processing lens holding mechanism 32A is held at a balanced position.

  Further, when the processing lens 31 is moved in the y direction, the control device 50 controls the current flowing through the electromagnet 330a of the third actuator 330 (3) and the fourth actuator 330 (4). As a result, the four second leaf springs 337 having both ends fixed to the holding member 335 and the fixing base 35 are bent in the xy plane, and the third actuator 330 (3) and the fourth actuator 330 ( The position of the processing lens holding mechanism 32A is held at a position where the electromagnetic force of 4) and the elastic force of the second leaf spring 337 are balanced.

  At the same time, the x-direction position detector 331x measures the distance to the x-direction position detector target 332x, and the control device 50 reads the x-direction position information from the x-direction position detector 331x. Then, the control device 50 performs feedback control of the lens position so that the difference between the set value (target value) and the position information (feedback value) becomes small.

  By providing such a configuration, it is possible to obtain the same effect as the laser processing apparatus of the first embodiment, and furthermore, since the magnetic moving mechanism 33A includes an elastic hinge, a current is supplied to the electromagnet 330a. Even in a state where it does not flow, the processing lens holding mechanism 32A can be kept at a fixed position by the restoring force of the elastic hinge.

  That is, the fixed position of the processing lens holding mechanism 32A in a state where no current flows through the electromagnet 330a corresponds to the position that should be the original point, and the measured value by the position detector is a result of temperature drift. The origin position is reproducible based on a certain restoring force by the elastic hinge.

  Therefore, the position information can be compensated by obtaining the measured values of the x-direction position detector 331x and the y-direction position detector 331y as the origin position in a state where the current of the electromagnet 330a is zero. That is, since the position where the force of the elastic hinge is balanced can be made coincident with the origin of the position information of the processing lens, it is not necessary to extremely increase the current value of the specific electromagnet 330a when moving the lens. The current value of 330a can be made uneven.

  Therefore, even if the magnetic movement mechanism 33A changes in temperature due to heat generated by the electromagnet 330a, absorption of the laser beam 22, etc., the center of the processing nozzle 36 and the optical axis 22a of the laser beam 22 can be eccentric with high speed and high accuracy. In addition, the optical axis 22a of the laser beam 22 can be deviated from the opening center 37a of the processing nozzle 36 in the processing progress direction. As a result, the processing gas 43 and the melt 4 can flow smoothly along the cutting groove 3, and a high-quality cutting process can be performed.

  As described above, according to the second embodiment, the magnetic moving mechanism includes the elastic hinge. As a result, the same effect as in the first embodiment can be obtained, and the position information can be compensated based on the origin position measured with the electromagnet current set to zero. As a result, since the position where the force of the elastic hinge is balanced can be matched with the origin of the position information of the processing lens, it is not necessary to extremely increase the current value of a specific electromagnet when moving the lens. An effect can be obtained.

  1 Workpiece, 2 Piercing hole, 3 Cutting groove, 4 Melt, 10 Laser oscillator, 20 Laser beam transmission system, 21 Mirror, 22 Laser beam, 22a Optical axis, 30 Processing head body, 31 Processing lens, 31a Processing lens central axis , 32, 32A Processing lens holding mechanism, 33, 33A Magnetic movement mechanism, 330 (1) First actuator, 330 (2) Second actuator, 330 (3) Third actuator, 330 (4) Fourth Actuator, 330a Electromagnet, 330b Magnetic target, 331 position detector, 331x x-direction position detector, 331y y-direction position detector, 332 position detector target, 332x x-direction position detector target, 332y y-direction position detector target 333x second x-direction position detector, 33y second y-direction position detector, 334x second x-direction position detector target, 334y second y-direction position detector target, 335 holding member, 336 first leaf spring, 337 second leaf spring, 34 partition Plate, 35 Fixed base, 36 Processing nozzle, 37 opening, 37a Center of opening, 40 Gas supply device (gas supply unit), 42 Gas valve, 41 Processing gas introduction pipe, 43 Processing gas, 50 Control device (control unit), 100 Laser Processing equipment.

Claims (6)

A laser oscillator for oscillating a laser beam;
A gas supply for supplying the processing gas;
Processing that cuts the workpiece to be processed by emitting the laser beam oscillated from the laser oscillator from a processing nozzle and ejecting the processing gas supplied from the gas supply unit from the processing nozzle. The head body,
Based on the type and processing conditions of the workpiece, the beam output of the laser beam oscillated from the laser oscillator and the supply amount of the processing gas supplied from the gas supply unit are controlled and emitted from the processing nozzle. A laser processing apparatus comprising: a control unit that controls the amount of eccentricity that offsets the optical axis of the laser beam with respect to the opening center of the processing nozzle,
The processing head body is
A processing lens for condensing the laser beam oscillated from the laser oscillator toward the workpiece;
A magnetic movement mechanism that moves the processing lens biaxially in a plane perpendicular to the optical axis of the laser beam or in a curved surface by magnetic driving by a plurality of electromagnets;
A position detector for measuring position information of the processing lens,
The control unit feedback controls the current values of the plurality of electromagnets so that the position information measured by the position detector becomes a target position, and moves the processing lens to the target position by two axes. Performing the eccentricity control and measuring by the position detector during the execution of the feedback control based on the origin position information measured by the position detector at the position that should be the original origin before the execution of the feedback control. Compensating the position information to be performed. A laser processing apparatus, comprising: In the laser processing apparatus of Claim 1,
The said control part measures the said origin position information before execution of the said feedback control by setting the electric current value of these electromagnets equally. The laser processing apparatus characterized by the above-mentioned. In the laser processing apparatus of Claim 1,
The magnetic movement mechanism has an elastic hinge mechanism such that when the current values of the plurality of electromagnets are set to 0, the processing lens is originally at a position that should be the origin,
The control unit measures the origin position information before executing the feedback control by setting current values of the plurality of electromagnets to 0. The laser processing apparatus, wherein: The laser processing apparatus according to any one of claims 1 to 3,
The control unit measures the origin position information before execution of the feedback control, when the laser processing head is stopped, and when the laser beam is not irradiated on the workpiece. Laser processing equipment. In the laser processing apparatus of any one of Claims 1 thru | or 4,
The laser processing apparatus, wherein the control unit performs the eccentricity control so that a central axis of the processing lens is positioned on a processing progress direction side with respect to the opening center of the processing nozzle. When a laser beam is emitted from the machining head and a machining gas is ejected at the same time as a workpiece to be machined is cut, a machining lens that focuses the laser beam toward the workpiece is used as the optical axis of the laser beam. A laser processing method for controlling the amount of eccentricity between the center of the processing nozzle for ejecting the processing gas and the center of the optical axis of the laser beam by moving in two axes in a vertical plane or curved surface,
Measuring the position that should be the original origin of the processing lens as the origin position information before executing the control of the eccentricity; and
Compensating position information of the processing lens measured during execution of the control of the eccentricity based on the origin position information;
And a step of controlling the amount of eccentricity so that the compensated position information becomes a target position.

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