JP3511049B2 - Laser processing equipment - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laser processing apparatus for performing processing such as cutting and welding with a laser beam, and more particularly to a laser processing apparatus capable of accurately performing small circle processing.

[0002]

2. Description of the Related Art Conventionally, in laser processing such as cutting of metal, for example, X, Y, and Z provided in a laser processing apparatus.
In addition to the moving shaft for machining the shaft, an articulated machining device having a plurality of machining rotary shafts provided in the machining head is used, and three-dimensional machining of a flat plate or a three-dimensional work based on a predetermined machining program. Is being done.

In particular, when performing circular machining, a predetermined pattern program for controlling the machining head so as to draw a circular locus using a composite vector of a plurality of axes is created, and the circular machining is performed by this pattern program. It was done.

[0004]

However, in the case of the above-mentioned conventional technique, there is a problem that the control of the machining head is complicated and a complicated movement is caused by a plurality of control axes. Especially, in the three-dimensional work, there is a problem of interference between the work and the machining head, and further, since the control is performed by calculation,
There was a problem that a continuous and precise circular locus could not be obtained.

In order to solve such a problem, for example, as shown in Japanese Patent Laid-Open No. 63-76784, another rotating shaft is added to the head, and the reflecting mirror is moved in the radial direction from the center of the rotating shaft. By providing a slide mechanism that translates the optical axis in parallel and expands and contracts, and also uses a head that also moves the condensing part together with the mirror, the desired radius can be obtained by rotating the rotary shaft only in accordance with the slide amount. The method of performing circle processing is also adopted. However, the head using the slide cylinder as described above has a drawback that the head itself having a slide mechanism for moving the mirror becomes large, and there is also a problem that it becomes expensive in manufacturing. Also,
There is also a problem that alignment adjustment of the optical axis of the mirror for reflection is structurally difficult.

Therefore, as a further solution, there is one disclosed in Japanese Patent Laid-Open No. 2-169195. Here, similarly to the above, another method is adopted in which another rotating shaft is added to the head and the condensing lens is moved in the radial direction from the center thereof to decenter the condensing point. In this case, the straight line connecting the incident point of the laser optical axis to the lens and the condensing point has an angle with the rotation axis, and the work cut surface is not perpendicular to the work upper surface and the cutting accuracy There is a problem that is bad.

The present invention has been made in view of the above problems of the prior art, and an object of the present invention is to provide a laser machining apparatus capable of highly accurate small circle machining with a simple structure.

[0008]

SUMMARY OF THE INVENTION The present invention is directed to an introduction portion into which laser light is introduced from a laser oscillator through a laser optical path, and a rotation rotatable about the optical axis with respect to the introduction portion. It has a laser processing head provided with a cylinder and a lens holder that holds a condenser lens and is attached to the rotating cylinder, and transmits the laser light guided to the introduction part and transmits the laser light to a predetermined axis. A prism moving member which has a pair of prisms attached to the rotary cylinder along the optical axis direction in parallel with each other and each having an inclined surface, and which relatively separates the pair of prisms in the optical axis direction. And a lens moving device for moving the lens holder with respect to the rotary cylinder in a direction orthogonal to the optical axis and in a refracting direction of laser light by the prism. Further, of the pair of prisms, the laser light incident side prism is moved in the optical axis direction by the prism moving member, and the laser light emitting side prism and the condenser lens of the pair of prisms are integrally provided. A laser processing device in which a condenser lens integrally provided with this prism is moved by the lens moving device.

Further, according to the present invention, an introduction portion into which laser light is introduced from a laser oscillator through a laser optical path, a rotary cylinder rotatable about the optical axis with respect to the introduction portion, and a condenser. And a laser processing head provided with a lens, each of which has a surface that transmits the laser light guided to the introduction portion and that is inclined by a predetermined angle with respect to the optical axis thereof and is parallel to each other in the optical axis direction. A laser processing apparatus provided with a pair of prisms attached to the rotary cylinder along the laser beam emitting side with respect to the condenser lens, and a prism moving member that relatively separates the pair of prisms in the optical axis direction. Is. Further, a prism moving member that forms a laser light incident side prism of the pair of prisms integrally with the condenser lens, and separates the laser light emitting side prism of the pair of prisms in the optical axis direction. It is a laser processing device provided.

[0010]

In the laser processing apparatus of the present invention, the lens moving device causes the lens to be decentered from the center of rotation of the rotary cylinder by the radius of the circle to be processed, and the pair of prisms are moved in accordance with the movement of the lens holder. The optical axis of the laser light emitted from the laser light emitting prism of the pair of prisms is moved in the same direction as the moving direction of the lens in parallel by a distance equal to the eccentricity amount. By rotating the rotary cylinder, relatively small circle machining can be performed easily and accurately.

Further, in the laser processing apparatus of the present invention, the prism is arranged on the laser beam emitting side of the condenser lens,
By moving one of the prisms in the direction of the optical axis of the laser light, the optical axis of the emitted laser light is moved in parallel, and by rotating the rotary cylinder in the same manner as above, a relatively small circle can be easily processed. This is something that can be done accurately.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. The laser processing apparatus of this embodiment is shown in FIG.
As shown in, the movable table 3 is fixed to the fixed column 2.
Is provided so as to be movable in the X-axis direction in the drawing, and a Y-axis saddle 4 is provided in the fixed column 2 so as to be movable in the Y-axis direction in the drawing. Furthermore, the above Y-axis saddle 4
Further, a Z-axis saddle 5 is provided so as to be movable in the Z-axis direction in the drawing. A head support 6 is attached to the Z-axis saddle 5, and a laser processing head 10 is attached to the head support 6.

The laser processing head 10 includes a rotating bracket 7 which is attached to the head support 6 and rotates about an α axis which coincides with the optical axis of laser light from the head support 6.
The rotating bracket 7 is provided with an introducing portion 8 rotatably provided around a β axis orthogonal to the α axis.
The optical axis of the laser beam is set at 90 at the base end of the rotating bracket 7.
A mirror 11 that turns in a direction that coincides with the β-axis at an angle of degrees is attached, and a mirror 12 that reflects the laser light reflected by the mirror 11 by 90 degrees is also attached to the introduction portion 8. As a result, the three-dimensional position of the head support 6 is determined by the three-axis control of X, Y, and Z, and the laser irradiation direction of the processing head 10 is determined by adding the two axes of α and β. It has become so.

A laser oscillator 9 is provided on the side of the column 2.
Is provided between the laser oscillator 9 and the processing head 10, and a Y-axis duct 1a and a Z-axis duct 1b in which a laser optical path for guiding laser light is formed are provided. Then, the laser light is transmitted from the Z-axis duct 1b to the rotating bracket 7
It is introduced to the tip of the processing head 10 by the mirror 11 and the mirror 12 of the introduction unit 8.

As shown in FIG. 1, a slide cylinder 13 is attached to the processing head 10 at the tip of the introduction portion 8 so as to be slidable in the Z-axis direction along the incident laser optical axis. A rotary cylinder 14 is attached to the cylinder 13 via a bearing 15 so as to be rotatable about the laser optical axis. Further, as shown in FIG. 2, a motor 16 for rotation driving is mounted on the slide cylinder 13, and an output shaft (not shown) of the motor 16 has an outer periphery of the rotation cylinder 14 via a gear (not shown). It meshes with the gear 17 formed on the.

Inside the rotary cylinder 14, a prism 20 having a right-angled triangular cross section, which is fixed above the rotary cylinder 14, is provided with its center coincident with the incident optical axis of the laser light. The upper surface 20a of the prism 20 is orthogonal to the laser optical axis, and the surface on the emitting side obliquely intersects the laser optical axis at a predetermined angle 2
It is formed in 0b. Below the prism 20, a prism 22 having a slope 22b parallel to the slope 20b of the prism 20 is provided facing the bottom of the slope 20a, and a lower surface 22a of the prism 22 is a surface orthogonal to the laser optical axis. Has been formed.

The prism 22 is fixed to a support member 24, guided by a pair of guide holes 26 formed in the support member 24, and is vertically movable along a pair of guide posts 28 in the Z-axis direction. . The guide post 28 constitutes a prism moving member together with the guide hole 26, and a lens holder 30 provided at the lower end of the rotary cylinder 14.
Is projected on. The lens holder 30 includes a cylindrical holder body 30a and a support body 30b that integrally supports the holder body 30a. This lens holder 3
In the holder body 30a of No. 0, a condenser lens 31 for condensing the laser light on the work W is attached by a lens mount 32. And this lens holder 30
2 is a portion of the support 30b, which is slidably supported in the left-right direction in FIG. 1 along a pair of guides 33 provided on both sides of the lower end of the rotary cylinder 14 as shown in FIGS. ,
The lens 31 moves together with the movement of the lens holder 30.

As shown in FIGS. 3 and 4, the lens holder 30 is moved by the lens moving device 34 in a direction in which the prism 20 refracts the laser light and is orthogonal to the optical axis of the laser light. The moving device 34 includes a motor 35 and a ball screw mechanism 37 having a screw shaft 36. A pulley 38 is attached to the output shaft 35a of the motor 35, and a timing belt 40 is wound around the pulley 39 on the screw shaft 36 side. Then, the nut portion 41 of the ball screw mechanism 37 is provided integrally with the lens holder 30, and the lens holder 30 is moved back and forth in the axial direction of the screw shaft 36 by the rotation of the screw shaft 36.

As shown in FIG. 5, an interlocking mechanism 42 which is a prism moving member for moving the supporting member 24 of the prism 22 is attached to the inner surface of the lens holder 30 on the side of the rotary cylinder 14. This interlocking mechanism 42 is used for the lens holder 30.
A holding member 43 fixed to the holding member 43 and an L-shaped swinging member 45 pivotally supported by the holding member 43 by a holding shaft 44. The L-shaped swinging member 45 has its corners pivotally supported by the holding shaft 44, a U-shaped notch 45a formed at the lower end, and a U-shaped notch at the other tip. The portion 45b is formed. The notch portion 45 a engages with the fixed pin 46 that protrudes inward from the inner surface of the rotary cylinder 14, and the notch portion 45 b engages with the moving pin 47 that projects laterally of the support member 24. is doing.

As shown in FIG. 1, all the mechanical parts such as the lens moving device 34 and the interlocking mechanism 42 are covered with a cover 48.
It is covered with and is protected from laser light and spatter. A nozzle 50 that emits laser light is fixed to the lower end of the lens holder 30, and the tip of the nozzle 50 is located close to the work W.

A gap sensor composed of a capacitance sensor (not shown) for detecting the distance from the work W is attached to the tip of the nozzle 50, and the output of the gap sensor is input to a control device (not shown). ing. Then, a gap control device 52 controlled by this control device is provided in the introduction part 8, a sliding part 53 of this gap control device 52 is fixed to the slide tube 13, and the slide tube 13 emits laser light. The gap between the nozzle 50 and the workpiece W is controllable by sliding in the axial direction.

Further, the processing head 10 of this embodiment includes
An air introduction pipe line 60 for introducing prism cooling air is formed in the slide cylinder 13, and an opening 61 of the air introduction pipe line 60 opens toward the upper surface 20 a of the prism 20. Further, another air introduction conduit 62 is formed toward the slope 20b of the prism 20. Further, an air introduction conduit 63 for supplying cooling air to the slope 22b and the bottom surface 22a of the prism 22 that is movably provided.
Is formed on the lens holder 30. The air introduction pipe line 63 communicates with an air supply pipe 64 projecting from the lens holder 30, the air supply pipe 64 is inserted into a guide hole 66 formed in the support member 24, and the movement of the support member 24 is prevented. It is possible. The guide hole 66 is formed with an opening 67 opening toward the inclined surface 22b of the prism 22 and an opening 68 opening toward the lower surface 22a. Further, the lens holder 30 is provided with an opening 69 that is connected to the air introduction conduit 63 and opens toward the incident surface of the condenser lens 31. Further, the holder main body 30a of the lens holder 30 is provided with an introduction port 70 for an assist gas used during processing.

Next, the operation of the laser processing apparatus of this embodiment will be described below. The operation of the processing head 10 is similar to that of a known laser processing head, and the processing head 10 moves in the X, Y, and Z directions according to the workpiece,
The machining head 10 rotates about the α and β axes, and
Dimensional processing is performed. As for the type of processing, the power of the laser can be adjusted to appropriately perform cutting, welding and the like.

Further, especially when small circle machining is performed, the motor 3
The lens moving device 34 is driven by 5, and the condenser lens 31
The center of is translated from the center of rotation of the rotary cylinder 14 by the radius R of the circle to be drawn. At this time, the support member 24 moves together with the lens holder 30 by the guide post 28 protruding from the lens holder 30. Further, at this time, the interlocking mechanism 42 causes the holding member 43 of the interlocking mechanism 42 to move with the movement of the lens holder 30, and the swinging member 45 engaged with the fixing pin 46 as shown in FIG. Swing clockwise. Then, the notch portion 45b engaged with the moving pin 47 protruding from the supporting member 24 causes the supporting member 24
Is pushed down diagonally. As a result, the prism 2
2 moves obliquely downward with respect to the prism 20 by a predetermined amount in the same posture. As shown in FIG. 6, this downward movement amount is a distance required for the optical axis of the laser light to move in parallel from B1 to B2 in the same direction by a distance R equal to the movement amount R of the lens 31. .

In this state, X,
The machining head 10 is controlled by simultaneously controlling the Y and Z axes and the α and β axes.
Is positioned in a predetermined processing position at a predetermined processing position.
As a result, the incident optical axis B1 of the processing head 10 is located at the center of the circle to be drawn, and the optical axis is set to an angle orthogonal to the plane including the circle. At this time, the tip of the nozzle 50 is positioned on the circumference of the circle to be drawn, and the eccentric emission optical axis B
2 coincides with this circumference. And in this state,
By irradiating laser light while driving the rotor 16 and rotating the rotary cylinder 14, circular machining with a desired radius R can be easily performed without moving the other control shafts. On the contrary to the above, it is also possible to drive the motor 35 to obtain a predetermined processing radius after positioning the processing head 10 at a predetermined processing position.

In addition to the NC control axis, the rotary axis of the rotary cylinder 14 is the U axis, and the rotary axis for moving the condenser lens 31 is the V axis. Both axes can be automatically controlled by a machining program. In this case, the optical axis control for performing processing of any shape from piercing to circular processing is performed by X, Y,
It can be performed by simply controlling the U and V axes without moving the Z axis. Therefore, it is possible to perform not only a perfect circle but also various shapes such as an ellipse and a rectangle by organizing a machining program and adding software separately.

According to the laser processing apparatus of this embodiment, by simply positioning the processing head 10 at a predetermined processing position and in a predetermined processing posture, the rotary drive unit rotates the rotary cylinder 14 to rotate the rotary head 14 in that state. -By irradiating the laser light, the focal point of the laser light moves while drawing a circular locus of a predetermined radius centered on the rotation center of the rotary cylinder 14 to perform small circle machining such as cutting by the laser light. Easy to do. Furthermore, since the prism 22 is provided so as to be movable obliquely downward, the prism 22 can be made small, which also contributes to the reduction in size and weight of the processing head 10.

The pair of prisms 20 and 22 may be arranged so that the laser optical axes can be moved in parallel, and one or both of them may be moved relative to each other. . The movement of the prism 22 is
In addition to the one linked with the lens holder 30, the lens holder 30 may be independently controlled to move, and a large prism 22 is provided.
It may be one that is simply moved downward. That is, if the lower prism 22 is large enough to cover the required movement amount R, the prism 22 need only move downward by a necessary amount.

Next, a second embodiment of the present invention will be described with reference to FIG.
It will be explained based on. Here, the same members as those in the above-described embodiment are designated by the same reference numerals, and the description thereof will be omitted. This example
The optical member 72 in which the condenser lens 31 is integrated is provided on the bottom surface 22a of the prism 22 of the first embodiment.
In this case, the prism 20 is moved up and down in the optical axis direction, and the optical member 72 in which the prism 22 and the condenser lens 31 are integrated.
Should be attached to the lens holder 30 and moved in the direction orthogonal to the optical axis as in the first embodiment.

Next, a third embodiment of the present invention will be described with reference to FIG.
It will be explained based on. Here, the same members as those in the above-described embodiment are designated by the same reference numerals, and the description thereof will be omitted. In this embodiment, a pair of prisms 20 and 22 are arranged on the laser light emitting side of the condenser lens 31. In this case, the condenser lens 31 and the prism 20 may be fixed, and may be located at the rotation center of the rotary cylinder 14. Further, the moving member of the prism 22 may be the same as that of the above-mentioned embodiment, and the lens holder 30 of the first embodiment holds a simple window instead of the condenser lens in this embodiment,
In addition, any moving member that can move by the radius R of the desired machining circle in the direction orthogonal to the optical axis while holding the nozzle 50 at the tip may be used.

Next, a fourth embodiment of the present invention will be described with reference to FIG.
A description will be given based on 0. Here, the same members as those in the above-described embodiment are designated by the same reference numerals, and the description thereof will be omitted. In this embodiment, an optical member 71 in which the prism 20 of the pair of prisms 20 and 22 of the third embodiment and the condenser lens 31 are integrated is provided. In this case, the optical member 71 may be fixed and may be located at the rotation center of the rotary cylinder 14. The moving member of the prism 22 may be the same as that of the first embodiment as in the third embodiment, and the lens holder 30 of the first embodiment is orthogonal to the optical axis in this embodiment. Radius R of the desired machining circle in the direction
Any moving member that can move by an amount may be used.

The laser processing head of this invention is shown in FIG.
Not only the laser processing device as shown in Fig. 4, but also other articulated robots for laser processing and laser processing machines for flat plate processing can be attached, and the processing target is As for the kind of member, resin and various other materials can be arbitrarily selected in addition to metal.

[0033]

According to the present invention, the condenser lens inside the machining head is moved in accordance with the radius of the circle to be machined, and one of the pair of prisms is moved together with this to rotate the laser optical axis. Since the cylinder is decentered in parallel to the rotation axis and is aligned with the center of the lens, it is possible to perform highly accurate small circle machining with a simple structure and without complicated control. Further, since the prism is arranged below the condenser lens and the optical axis of the laser light is moved in parallel only by moving the prism in the optical axis direction, a simple mechanism does not require complicated control. It is possible to perform highly accurate small circle machining.

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing a first embodiment of a processing head of a laser processing apparatus according to the present invention.

FIG. 2 is a partially cutaway front view of the processing head of this embodiment.

FIG. 3 is a bottom view of the lens holder of this embodiment.

4 is a cross-sectional view taken along the line AA of FIG.

FIG. 5 is a front view showing the interlocking mechanism of this embodiment.

FIG. 6 is an explanatory view showing the movement of the prism of this embodiment.

FIG. 7 is a schematic view showing a laser processing apparatus of this embodiment.

FIG. 8 is a schematic diagram showing an optical system of a second embodiment of the present invention.

FIG. 9 is a schematic view showing an optical system of a third embodiment of the present invention.

FIG. 10 is a schematic diagram showing an optical system of a fourth embodiment of the present invention.

[Explanation of symbols]

8 Introduction 9 Laser oscillator 10 Processing head 14 rotating cylinder 20,22 prism 30 lens holder 31 Condensing lens 34 Lens moving device 42 interlocking mechanism

Claims (4)

(57) [Claims] 1. An introduction part into which laser light emitted from a laser oscillator is introduced via a laser optical path, and a rotary cylinder rotatable about the optical axis of the laser light with respect to this introduction part. In a laser processing apparatus having a laser processing head including a lens holder that holds a condenser lens provided on the rotary cylinder, a laser beam guided to the introduction portion is transmitted and tilted at a predetermined angle with respect to the optical axis. A pair of prisms having parallel surfaces, which are parallel to each other and are attached to the rotary cylinder along the optical axis direction, and a prism moving member that relatively separates the pair of prisms in the optical axis direction, A lens moving device that moves the lens holder in a direction orthogonal to the optical axis with respect to the rotating cylinder in a refraction direction of laser light by the prism, wherein the prism moving member is
It has an interlocking mechanism that interlocks with the movement of the lens moving device.
Only the amount corresponding to the movement amount of the lens holder
A laser processing apparatus characterized by moving one of them. 2. A laser beam incident side prism of the pair of prisms is provided movably in the optical axis direction by the prism moving member, and a laser beam emission side prism and the condenser lens of the pair of prisms. And are integrated,
2. The laser processing according to claim 1, wherein the condenser lens integrally provided with the prism is moved by the lens moving device in a direction orthogonal to the optical axis and in a refracting direction of laser light by the prism. apparatus. 3. An introduction part into which laser light emitted from a laser oscillator is introduced via a laser optical path, and a rotary cylinder rotatable about the optical axis of the laser light with respect to this introduction part. In a laser processing apparatus having a laser processing head composed of a condenser lens for condensing laser light, each has a surface that transmits the laser light guided to the introduction part and is inclined at a predetermined angle with respect to its optical axis. Then, a pair of prisms attached to the rotary cylinder in parallel with each other along the optical axis direction are provided on the laser light emitting side of the condenser lens, and the pair of prisms are relatively separated from each other in the optical axis direction. A laser processing apparatus provided with a prism moving member. 4. A prism in which a laser light incident side prism of the pair of prisms is formed integrally with the condensing lens, and a laser light emitting side prism of the pair of prisms is separated in the optical axis direction. The laser processing apparatus according to claim 3, further comprising a moving member.