JPS6173820A - Laser hardening device - Google Patents

Abstract

PURPOSE:To provide a titled device which hardens satisfactorily a metallic surface without generating the surface melting state by the constitution consisting in charging successively the angle for attaching each reflecting specular face of a polyhedral reflecting mirror constituted to a rotating body and hardening the metallic surface by the beam reflected from the rotating body. CONSTITUTION:This laser hadening device rotates the rotating body 1 constituting the polyhedral reflecting mirror made to a prism or pyramidal shape in an arrow direction by means of a motor 2, irradiates the laser beam condensed by a lens 3 thereto and hardens the work W moving in the arrow direction by the reflected beam thereof. The respective reflecting specular faces 11, 12- of the above-mentioned polyhedral reflecting mirror are attached successively at prescribed angle differences in the above-mentioned device. The respective scanning focal lines 41, 42- by the face 11- form scanning 4 of a prescribed width by spacing from each other at the distances conforming to the differences in the above-mentioned attaching angle. The irradiation time of the beam energy in the surface to be hardened is thus increased and the deep and uniform hardening is made possible without melting.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a laser hardening device, and more particularly to a laser hardening device using a rotating polygonal reflecting mirror.

[Conventional technology]

Conventionally, as this type of apparatus, there has been one shown in FIG. 5 (Machines and Tools, APR, 1984P-58).

In the figure, (1) a rotating body constituting a polygonal prism-shaped or polygonal pyramid-shaped polygonal reflecting mirror, (2) a high-speed motor that rotates the rotating body (1) at a high speed of about 2000 to 10000 r, p, m; (3) is a germanium lens that condenses the laser beam from the laser oscillation head and irradiates it onto the polygonal reflecting mirror, and focuses the reflected beam near the surface of the workpiece W.

Next, the effect will be explained. The laser beam from the laser oscillation head is focused by a lens (3) and is focused on each surface (
1at) to (1an) and reflected, at a constant speed,
For example, the beam is focused near the metal surface of the workpiece W moving at about 1 m/min, and the concentrated beam energy heats the metal surface of the workpiece W to perform surface hardening. In this case, since the rotating body (1) is rotating at high speed, each reflecting mirror surface (1a+) - (law)... (1an
) and are reflected sequentially. Reflection on each reflecting mirror surface is performed while moving from the ridge line with the front surface to the ridge line with the next surface through the entire flat mirror surface, and due to the change in the angle of incidence and reflection due to the rotation, the reflection on the workpiece The focal point (4) on the surface of W is moved so as to scan linearly with a predetermined width. On the other hand, since the workpiece W is moving at a constant speed in a direction perpendicular to the scanning focal line (4), each reflecting mirror surface (la,) to (Ian)
The scanning focal lines (4) are moved parallel to each other, and the metal surface is hardened with a predetermined hood.

[Problem that the invention seeks to solve]

In the conventional laser hardening equipment described above, each reflective mirror surface of the multifaceted mirror is installed at an equal distance from the axis, so
The scanning focal lines of each reflecting mirror surface touch 14 times in parallel and sequentially with a width corresponding to the movement of the workpiece and the rotational speed of the rotating body. Therefore, the degree of concentration of beam energy per unit time in a unit area by a laser beam causes linear cracking force, which causes surface melting and deteriorates hardening performance. especially,
At both ends of the hardened portion, the degree of energy concentration was particularly high, making it impossible to achieve uniform hardening, and the surface condition deteriorated due to melting. In addition, since it is a linear quenching process,
It is easily affected by the shape of the beam (mode, light focusing ability), and there are problems such as uniform hardening being impossible.

This BA is made to solve such problems, and the purpose is to provide a laser hardening equipment R that can obtain good furnace hardening performance.0 [Problems? Means for Solving] In the laser hardening apparatus according to the present invention, the mounting angles of the respective reflecting mirror surfaces of the multifaceted reflection C formed on the rotating body are made to differ by a predetermined angle difference. ]-Characteristics.

[Effect]

Since the present invention is configured as described above, movement of the beam focus due to reflection from side edge to side edge on each reflecting mirror surface is the same as in the conventional example, but parallel scanning by adjacent reflecting mirror surfaces is possible. The distance between the focal lines is separated by a width corresponding to the difference in the mounting angle of the reflecting mirror surfaces, and by the high-speed rotation of the rotating body and the constant speed movement of the workpiece, multiple scanning focal lines within a predetermined plane, that is, a rectangular plane. The beam energy is distributed and irradiated. Therefore, the beam energy vs. time on the hardened surface becomes longer, and the hardening depth can be increased without causing surface melting. ! - can be deepened and over-irradiation of the beam energy at both ends of the hardened part (1 avoided);

Also, since it is a planar hardening, it is uniformly hardened without being affected by the shape of the laser beam (mode, light focusing ability). It can be carried out.

〔Example〕

Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

In Figure 1, (1) is a rotating body, (1,) ~ (1
,,) are the rotating bodies (reflecting mirror surfaces sequentially attached to the IH at a predetermined angle difference, (2) is the motor that rotates the rotating body (1) at high speed, (3) is the germanium lens, (4) ,)
~(4tz) σ is the scanning focal line on the workpiece W by each reflecting surface.

Next, the effect will be explained. As shown in FIGS. 2 and 5, each reflective mirror surface (1,) to (1□,) attached to the rotating body (1) has an installation angle of (1,
) are arranged at different angles of 6 in sequence, such as 11θ, (1□) and 10θ. In this way, the laser beam from the laser f emitter head is focused by the lens (3), and is focused on each of the reflecting mirror surfaces (11) to (11) of the rotating body (1) that is rotated at high speed by the motor (2). The beam is reflected and focused near the surface of the workpiece W moving at a constant speed, and the concentrated beam energy heats and hardens the metal surface.In this case, each scanning by each reflecting mirror surface The focal lines are the same as those of the conventional example, or the scanning focal lines (4,) to (4□) are formed by the reflecting mirror surfaces (1,) to (1°) whose mounting angles are sequentially different by a predetermined angle θ. Due to the rotation of the rotating body (1), the first scanning focal line (4,) and the last scanning focal line (4t) become parallel and separated by a distance of 7 degrees, compared to the difference in angle. A predetermined width is accommodated between the rotating body (11), and in one rotation of the rotating body (
1) high speed rotation, e.g. 2000-10000r, p,
rotation of about m and the speed of the punched workpiece W, for example, 1 m/
With a shift L... of the order of min., the subsequent rotation moves them so that they are adjacent to each other, and as shown in Fig. 4, irradiation is performed to fill the unirradiated area between each scanning focal line, resulting in a rectangular surface as a whole. irradiation with a beam energy of . This planar beam energy irradiation requires a longer irradiation time of the beam energy on the surface of the workpiece W, resulting in surface melting and
The hardening depth can be increased without causing melting, and deterioration of the surface condition due to surface melting, especially at both ends of the hardened portion, is prevented. Further, since the beam energy is irradiated in a planar manner, uniform hardening can be performed without being affected by the shape of the laser beam due to the mode, convergence, etc.

Furthermore, since hardening is performed in a planar manner, hardening can be performed not only in the scanning focal line and direct direction, but also when the workpiece W is moved in any direction, so that its applicability can be expanded.

〔Effect of the invention〕

Since this invention is configured as described above, the hardening depth can be deepened without surface melting, and hardening uniformity can be obtained, greatly improving the performance of laser hardening equipment, and furthermore, its application You can increase your sexuality.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram of an embodiment according to the present invention, Fig. 2 is a plan view of the rotating body, Fig. 6 is a line diagram showing the mounting angle of each reflecting mirror surface, and Fig. 4 is an explanation showing each scanning focal line. FIG. 5 is an explanatory diagram showing a conventional example. In the figure, (1) a rotating body, (1,) to (11) each reflecting mirror surface, (2) a high-speed motor, (3) a lens, and (4)
) is the scanning focal line. Note that the numbers in each figure indicate the same or corresponding parts.

Claims (2)

[Claims] (1) In a device in which a rotating body constituting a polygonal columnar or polygonal pyramid-shaped polygonal reflecting mirror is irradiated with a laser beam and the metal surface is hardened with the reflected beam, the mounting angle of each reflecting mirror surface of the polygonal reflecting mirror is A laser hardening device characterized by having sequentially different values. (2) The laser hardening apparatus according to claim 1, wherein the difference in the mounting angles of the respective reflecting mirror surfaces of the polygonal reflecting mirror is made equal over one circumference.