JPH041045B2 - - Google Patents

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention relates to a laser surface treatment device that uses a laser beam to improve the surface characteristics of a workpiece.
More specifically, the present invention relates to a device that can freely adjust the direction of irradiation of a laser beam onto the inner circumferential surface of a hole formed in a workpiece.

(Prior art) Laser hardening is applied to areas to be laser surface treated, such as the inner peripheral surface of a hole in a workpiece and the upper and lower surfaces of the workpiece, which have stepped portions where vertical and horizontal surfaces intersect. In this case, the vertical and horizontal surfaces were laser hardened separately.

(Problems to be Solved by the Invention) Therefore, in the past, the laser hardening operation was inefficient, and near the intersection of the vertical surface and the horizontal surface, there was a There were problems such as having to be hardened twice. In addition, when hardening the inner circumferential surface of a hole, if the cross-sectional shape of the laser beam is circular, the arcuate part will be in contact with the starting position and the end point of the hardening process along the inner circumferential surface. This makes uniform hardening difficult. Furthermore, if the above-mentioned positions at the start and end of the hardening process are superimposed, the start position of the hardening process will be heated and cooled twice, which is not desirable for uniform hardening. The problem is that there is no.

[Structure of the invention] (Means for solving the problem) In order to solve the conventional problem as described above,
The present invention includes an integration mirror that transforms the cross-sectional shape of the laser beam emitted from the laser oscillator into a square shape and substantially uniformizes the intensity distribution, on a support plate provided in the processing head of a laser surface treatment device. At the same time, a first bend mirror is installed to reflect the laser beam reflected from the integration mirror vertically downward, and a hole in the workpiece is attached to the lifting bracket supported vertically at the bottom of the support plate. A mirror holder bracket that can be freely inserted into the mirror holder is provided extending downward and supported horizontally so that the mirror holder bracket can be freely inserted into the mirror holder. A second bending mirror capable of horizontally reflecting the laser beam is provided, and a cooling chamber in which cooling water for cooling the second bending mirror can freely enter and exit the mirror holder supporting the second bending mirror in the upper part. and a mirror holder that is adjustable in angle about a horizontal axis of rotation perpendicular to the laser beam at a position that coincides with the axis of the vertical laser beam, and a gear provided at the bottom of the cooling chamber of the mirror holder. A pinion gear rotated by a small control motor attached to the lower end of the mirror holder bracket is engaged with the mirror holder bracket.

(Function) In the above configuration, by horizontally reflecting the laser beam incident on the bend mirror, the vertical surface of the workpiece can be irradiated, and the vertical surface can be laser hardened. By appropriately rotating the mirror holder to adjust the reflection direction and irradiating the intersection of the vertical and horizontal surfaces with a laser beam from, for example, a 45° direction, the vertical and horizontal surfaces are laser hardened in the same way. be able to.

As mentioned above, when laser hardening is performed, the cross-sectional shape of the laser beam is deformed into a rectangular shape.
In addition, since the strength distribution is made uniform, when connecting the start and end points of the hardening process, the rectangles are connected next to each other, and there is no need to overlap the start and end points, so that the hardening process is uniform throughout the entire area. Can be hardened.

(Example) Referring to FIGS. 1 and 2, a laser surface treatment apparatus 1 embodying the present invention includes a work table 3 that supports a work W to be surface-treated, and a side surface of the work table 3. A laser oscillator 5 that oscillates a laser beam LB to irradiate the workpiece W is provided at the position. Since this laser oscillator 5 may be of a general type, a detailed explanation thereof will be omitted.

The work table 3 is mounted in the X-axis direction (Fig. 1,
It is equipped with a movable table 7 that is movable in the horizontal direction (in the left-right direction in FIG. 2) and a rotary table 9 that is rotatable horizontally. (not shown). In this embodiment, the workpiece W is illustrated as a disk having holes H at an appropriate number of locations.

In the above configuration, by automatically performing the movement and positioning of the movable table 7 and the rotation and rotational positioning of the rotary table 9, a desired hole H of the workpiece W can be positioned at a predetermined position.

As can be understood from FIGS. 1 and 2, a column 11 is erected at a side position of the movement area of the work table 3. A guide member 13 extending across the top in the Y-axis direction is supported in a cantilevered manner. A processing head 15 that irradiates a desired position of the workpiece W with a laser beam LB from the laser oscillator 5 is supported on the guide member 13 so as to be movable in the Y-axis direction. This processing head 15
is equipped with an irradiation direction adjustment device 17 that can freely adjust the irradiation direction of the laser beam LB onto the workpiece W, as will be described in detail later. The processing head 15 is moved and positioned in the Y-axis direction by a servo motor 19 mounted on the column 11.

With the above configuration, the processing head 15 is moved and positioned in the Y-axis direction to correspond to the desired position of the workpiece W, and the workpiece W is irradiated with the laser beam LB from the laser oscillator 5 via the irradiation direction adjustment device 17. It will be understood that hardening of desired positions of the workpiece W can be performed.

By the way, when performing laser hardening on the surface of the workpiece W, if the reflectance of the workpiece surface is high, it is necessary to perform an appropriate coating treatment on the workpiece surface. Therefore, in this embodiment, a surface coating device 21 is arranged at a side position of the movement area of the work table 3. This surface coating device 21 acts to apply a suitable coating material such as manganese phosphate, carbon powder, silicon carbide, etc. to the desired surface of the workpiece W, and may be composed of, for example, a general coating robot or the like. be.

When performing laser hardening on a desired location of the workpiece W, in order to make the cross-sectional shape of the laser beam LB the desired cross-sectional shape and to make the intensity distribution of the beam approximately uniform within the cross-sectional shape to uniformly perform laser hardening, The processing head 15 is provided with beam deformation means.

More specifically, as shown in FIG. 3, the processing head 15 is provided with a vertical support plate 23, on which the laser beam LB oscillated from the laser oscillator 5 is transmitted. A first bend mirror 25 that reflects downward is attached.
Further, near the lower part of the support plate 23, an integration mirror 27 is mounted corresponding to the first bend mirror 25 so that the direction of reflection can be finely adjusted as appropriate.

The integration mirror 27 changes the cross-sectional shape of the laser beam LB from the laser oscillator 5.
In this example, the purpose is to transform the laser beam LB from a round shape to a square shape, and to make the beam intensity distribution approximately uniform within the cross-sectional shape of the laser beam LB.
A large number of rectangular plane mirrors 31 are mounted on a concave base 29. That is, a large number of plane mirrors 31
are appropriately arranged so that the focal plane has a rectangular shape and the beam intensity is uniform. Therefore, in other words, at the focal plane of the integration mirror 27, the laser beam
The cross-sectional shape of the LB is square, and the beam intensity is uniform over the cross-sectional area. Note that the focal length of the integration mirror 27 is set to be large.

Furthermore, a second bend mirror 33 is attached near the top of the support plate 23. This second bend mirror 33 reflects the laser beam LB from the integration mirror 27 vertically downward, and is provided so that the reflection direction can be finely adjusted. A concave lens 35 is disposed below the second bend mirror 33 as a device for collimating the laser beam LB. The focal position of this concave lens 35 is aligned with the focal point of the integration mirror 27. Therefore, the laser beam LB passing through the concave lens 35 becomes a parallel light beam with a square cross section and is irradiated vertically downward.

In order to irradiate the laser beam LB to the outer surface of the workpiece W or the inner circumferential surface of the hole H of the workpiece W, a bend mirror 37 that reflects the laser beam LB in an arbitrary direction is installed near the lower end of the concave lens 35. A mirror holder bracket 39 provided thereon is supported so as to be vertically movable and horizontally rotatable.

More specifically, as shown in FIG. 3, a ball screw mechanism (not shown) is provided on the back surface of the support plate 23, and by the operation of a servo motor 41 attached to the support plate 23, A lifting bracket 43 having an L-shaped cross section is provided to move up and down. An annular inner cylinder member 45 is rotatably supported at the lower part of the lifting bracket 43.
The mirror holder bracket 39 is attached to the lower part of the mirror holder.

The inner cylindrical member 45 is rotatably supported within a cylindrical outer cylindrical member 47 attached to the lower part of the lifting bracket 43. A driven pulley 51 is integrally attached to the upper part of the inner cylindrical member 45 and is rotatably supported by a boss portion of a flange member 49 attached to the lower part of the lifting bracket 43. This driven pulley 51 is a drive pulley 55 attached to the output shaft of a servo motor 53 attached to the lifting bracket 43.
and are interlocked and connected via a belt 57. Therefore, the mirror holder bracket 39 and the like are rotated by the operation of the servo motor 53.

The mirror holder bracket 39 rotatably supports a mirror holder 61 having a rotation shaft 59 in a direction perpendicular to the laser beam LB at a position coinciding with the axis of the laser beam LB.
The bend mirror 37 is attached to the mirror holder 61, and a cooling chamber 63 into which cooling water can freely enter and exit in order to cool the bend mirror 37 is formed in the attachment portion to which the bend mirror 37 is attached. Furthermore, the mirror holder 61 has a gear 65.
A small control motor 6 attached to the mirror holder bracket 39 is attached to this gear 65.
A pinion gear 69 rotated by 7 is engaged with the pinion gear 69. Therefore, by operating the control motor 67, the angle of inclination of the bend mirror 37 can be adjusted as desired, and the direction of reflection of the laser beam LB can be adjusted as desired.

In the above configuration, the work table 3
Hole H of workpiece W placed above or workpiece W
The outer surface of the mirror holder bracket 39 is made to correspond to the mirror holder bracket 39 as appropriate. After that, the lifting bracket 43 is lowered, and the mirror holder bracket 39 is inserted into the hole H of the workpiece W, so that the part of the inner peripheral surface of the hole H to be laser hardened corresponds to the bend mirror 37, or , the portion of the outer surface of the workpiece W to be laser hardened corresponds to the bend mirror 37.

As mentioned above, after matching the portion of the workpiece W to be laser hardened with the bend mirror 37,
When the laser beam LB is oscillated from the laser oscillator 5, the cross-sectional shape of the laser beam LB is transformed into a rectangular shape by the integration mirror 27, and after being made into parallel light by the concave lens 35, it enters the bend mirror 37. be done. and,
The bend mirror 37 irradiates the portion of the work W to be radar hardened. When laser hardening is performed on the inner circumferential surface of the hole H in the work W, the bend mirror 31 may be rotated by operating the servo motor 53. Moreover, when performing laser hardening on the circumferential surface of the workpiece W, the workpiece W may be rotated while being irradiated with the laser beam LB.

As described above, when performing laser hardening on the inner circumferential surface of the hole H in the workpiece W or the outer circumferential surface of the workpiece W, if the area to be laser hardened is near the intersection of the vertical plane and the horizontal plane, the control motor 67
By controlling the angle of inclination of the bend mirror 37, it is possible to irradiate the intersection with the laser beam LB from, for example, a 45° direction. Therefore, near the intersection, laser hardening can be performed simultaneously on the vertical and horizontal surfaces.

Furthermore, by adjusting the inclination angle of the bend mirror 37, the laser beam LB can be irradiated onto the laser hardened portion of the workpiece W from an obliquely upward direction or an obliquely downward direction. Therefore, for example, the outer periphery upper edge and lower end of the disc-shaped workpiece W,
Laser hardening can be performed without remounting the workpiece W. That is, the workpiece W placed horizontally can be irradiated with the laser beam from above and below.

Note that the present invention is not limited to the above-described embodiments, but can be implemented in other embodiments by making appropriate changes.

[Effects of the Invention] As can be understood from the description of the embodiments above, the gist of the present invention is as stated in the claims. According to the present invention, the following effects are achieved. It is.

First, the laser beam LB oscillated from the laser oscillator 5 is transformed into a rectangular cross-sectional shape by the integration mirror 27, and its intensity distribution is made substantially uniform. Therefore, when hardening the inner circumferential surface of a hole or the outer circumferential surface of a workpiece, for example, the boundary between the start and end of the hardening process will be in the form of adjacent rectangles touching each other, and There is no possibility that the entered part and finished part overlap. Therefore, the hardened portion can be hardened uniformly over the entire circumference.

Second, the mirror holder bracket 3 is provided at the bottom of the lifting bracket 43 that is movable up and down.
A mirror holder bracket 39 extends downward and is horizontally rotatable.
A mirror holder 61 supporting the second bend mirror 37 provided at the lower part of the mirror holder 61 is provided so as to be adjustable in angle. Therefore, for example, when hardening the upper surface and inner circumferential surface and the lower surface and inner circumferential surface of a hole formed in a workpiece, in the case of hardening the upper surface and inner circumferential surface, the laser beam LB may be heated diagonally. By adjusting the second bend mirror 37 so that the light is reflected downward and irradiating the upper edge of the hole, the upper surface and the inner circumferential surface can be hardened at the same time. In the case of the lower surface and the inner circumferential surface, the mirror holder bracket 29 is lowered into the hole and protrudes downward, and the direction of reflection of the laser beam LB by the second bend mirror 37 is adjusted diagonally upward, thereby forming the hole. By irradiating the lower edge with the laser beam LB, the lower surface and inner peripheral surface can be hardened simultaneously.

In this case, the angle of the mirror holder 61 is freely adjustable around the horizontal rotation axis 59 that is orthogonal to the laser beam LB at a position that coincides with the axis of the vertical laser beam LB.
The irradiation position can be precisely controlled.

Thirdly, since the mirror holder 61 is provided with the cooling chamber 63, the second bend mirror 37 can be effectively cooled.

Fourth, as a configuration for adjusting the angle of the mirror holder 61, a gear 65 is provided at the lower part of the cooling chamber 63 of the mirror holder 61, and a pinion is rotated by a small control motor 67 attached to the lower end of the bracket 39. Since the gear 69 is meshed with the mirror holder 69, the attachment portion of the mirror holder 61 to the mirror holder bracket 39 has a vertical configuration.
For example, compared to a case where a gear 65 is provided on the rotating shaft 59, the overall structure can be made thinner although it is longer in the vertical direction, and it can also be used when the hole H of the workpiece W is relatively small. It is possible.

[Brief explanation of drawings]

FIG. 1 is a front view of a laser surface treatment apparatus embodying the present invention, and FIG. 2 is a plan view thereof. FIG. 3 is an enlarged sectional view taken along the - line in FIG. 1. DESCRIPTION OF SYMBOLS 1... Laser surface treatment device, 15... Processing head, 39... Mirror holder bracket, 61...
Mirror holder, 37...Bend mirror.

Claims (1)

[Claims] 1 Processing head 15 in laser surface treatment equipment
An integration mirror 27 is provided on the support plate 23 provided in the laser oscillator 5 to transform the cross-sectional shape of the laser beam LB emitted from the laser oscillator 5 into a rectangular shape and to make the intensity distribution substantially uniform.
A first bend mirror 33 is attached and provided to reflect the laser beam LB reflected from the integration mirror 27 vertically downward, and the support plate 23
A mirror holder bracket 39, which can be freely inserted into the hole H of the work W, is provided on the lifting bracket 43 which is vertically movably supported at the lower part of the workpiece W, and which extends downwardly and is horizontally rotatably supported. A second bend mirror 37 is provided at the bottom of the holder bracket 39 and is capable of horizontally reflecting the laser beam LB reflected vertically downward by the first bend mirror 33. A cooling chamber 63 in which cooling water for cooling the second bend mirror 37 can freely enter and exit is provided in the mirror holder 61 which supports the above-mentioned second bend mirror 37 at the top, and a cooling chamber 63 is provided in which cooling water for cooling the second bend mirror 37 can freely enter and exit. A mirror holder 61 is provided so as to be adjustable in angle around an orthogonal horizontal rotation axis 59.
9 is engaged with a pinion gear 69 rotated by a small control motor 67 attached to the lower end of the laser surface processing apparatus.