JPH0422969B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a hardening device, and more particularly to a laser hardening device that uses a laser to harden a corner portion of a shaft or the like having an eccentric portion.

[Conventional technology]

In general, in shafts with stepped parts of various shafts or eccentric parts such as crankshafts, even if the corner parts are rounded, the strength is weak and the parts tend to crack or break. Ta.

For this purpose, the strength of the shaft has conventionally been increased by hardening the entire shaft or a portion of the shaft using a normal heat treatment method such as induction hardening.

[Problem that the invention seeks to solve]

However, in the conventional technology, there were variations in hardening and it was difficult to obtain a constant hardening depth. Furthermore, even if you want to harden only a certain part, the heat energy accumulates while hardening that part, and you end up having to harden the whole part, making partial hardening difficult and resulting in wasted effort and money. The point was hot. Furthermore, for shafts having eccentric parts, such as crankshafts, there is a problem in that the hardening process is difficult and inefficient.

The present invention has been proposed in view of the above circumstances, and its first object is to make it possible to harden the corners of the eccentric part of a shaft, such as a crankshaft, which has an eccentric part. to
It is an object of the present invention to provide a laser hardening device having a rotatable laser head so as to be able to perform partial hardening by rotating 180 degrees to harden the other corner.

The second object is to provide a laser hardening device in which a laser head moves in synchronization with a circular locus drawn by the rotation of an eccentric part such as a crankshaft having an eccentric part, and hardens the corner part of the eccentric part. That's true.

[Means and actions for solving problems]

The above object of the present invention was achieved by the following laser hardening apparatus. The configuration is a laser processing machine equipped with a laser oscillator, a control device for the laser oscillator, and an operation panel, which is movable in the vertical direction to polarize the laser beam oscillated from the laser oscillator in a predetermined direction. a laser head that is rotatably mounted in a plane orthogonal to the direction of movement and includes a mirror that irradiates the laser beam to the hardened area; a first drive device that moves the laser head in a vertical direction; a second drive device for rotationally indexing the laser head, a first rotation axis in a direction orthogonal to the direction of movement of the laser head, and a second drive device at an eccentric position parallel to the rotation axis. a table on which a workpiece is placed, a third drive device that rotates the workpiece on the table around the rotation axis, and a fourth drive that moves the workpiece in the axial direction of the rotation axis. a fifth driving device for moving the table in a direction perpendicular to the axial direction of the rotating shaft and the vertical movement direction of the laser head; When hardening the second shaft and the periphery of the shaft end, the laser head is moved toward the workpiece by the operation of the first drive device and the fifth drive device while the workpiece is rotated by the third drive device. Circular interpolation is performed so that the hardening point irradiated by the laser head that maintains the same direction is eccentric from the rotation axis of the workpiece by an amount equivalent to the axis diameter of the second axis and draws a circular trajectory. This is a laser hardening device that includes a control section for controlling the laser hardening device.

With the above configuration, when a crankshaft or the like having an eccentric portion starts rotating, the movement of the eccentric portion is caused by the movement of the table (Y axis) and the laser head (Z axis) perpendicular to the rotation axis. In synchronization with this, the laser head moves to harden the corner portion of the eccentric portion. When the hardening of a certain part is completed, the driving source inside the box is driven, and the cylindrical part connected to the laser head is rotated 180 degrees by the meshing of the driving gear and the gear, and the hardening of the opposite corner part is started. Start heat treatment.

〔Example〕

Hereinafter, one embodiment of the present invention will be described in more detail based on the drawings.

(1) First, a machine to which the device of the present invention is applied will be explained.

FIG. 1 shows an overall front view of a laser processing machine used in the present invention, and FIG. 2 shows an enlarged partial sectional view of the vicinity of the laser head.

1 and 2, a table 3 is provided on a bed 2 of a laser processing machine 1 so as to be movable in the X and Y directions by a drive source (not shown). A crankshaft 6 is placed on the table 3 and has one end rotatably held by a chuck 4 and the other end supported by a roller 5.
Now, a laser head 7 is attached to a box 8 to irradiate the crankshaft 6 with laser light, and the box 8 is attached to a unit 9 and communicates with a laser oscillator 10 located on the left. Further, there is an operation panel 11 on the right front side, and an oscillator control device 12 is movably provided on the left front side.

Next, the laser head 7 will be explained in detail. A mirror (not shown) is inserted into the tip of the laser head 7 so that the laser beam reflected from inside the cylindrical body 13 is further reflected at a specific angle and irradiated onto a desired corner of the crankshaft 6. It's getting old. The laser head 7 is connected to the cylindrical body 13 and rotatably supported by a bearing holder 15 and a bearing 14 provided in a box 8 attached to the unit 9. A gear 16 is fitted onto a part of the cylindrical body part 13, and meshes with a drive gear 19 connected to a drive source 18, which is a second drive device fixed to a bracket 17 in the box 8, to drive the drive source. 18 makes the cylindrical body part 13
The function is to rotate 180°. The cylindrical body part 13
The upper part of the laser head 7 is expandable and retractable.
can be moved up and down (in the Z direction) by the first drive device. Further, a mirror (not shown) is installed in the upper part of the cylindrical body part 13, and the laser oscillator 10
The laser beam emitted from the laser beam is reflected by 90 degrees and guided to the laser head 7.

The general operation of the laser processing machine configured as described above will be explained.

The laser beam emitted from the laser oscillator 10 travels through a predetermined path inside the laser processing machine 1, and is turned 90 degrees by a mirror provided in the cylindrical body 13 above the laser head 7. Proceed towards the tip. The focal length of the laser beam is adjusted by a lens (not shown) provided at a predetermined position inside the cylindrical body, and further by a mirror attached to the tip of the laser head 7, the focal length of the laser beam is adjusted to a predetermined position on the crankshaft 6, etc. The angle is adjusted and irradiated so that it faces the corner of the screen.

On the other hand, for example, the crankshaft 6 and the like are rotated by a drive source 21, which is a third drive device, with the journal portion 20 as a rotation axis (A axis). At this time, the laser head 7, which irradiates the corner part of the crankshaft 6 etc. which is eccentric, also
Movement of table 3 in the Y-axis direction and laser head 7
By moving in the Z-axis direction, the eccentric part moves in synchronization with and follows the rotation of the eccentric part. After the laser beam hardening of one corner is completed, the drive source 18 in the box 8 is driven to rotate the drive gear 19, and further rotate the gear 16 meshing with the drive gear 19. Then, the other corner part is heat treated with laser light.
Rotate it 180 degrees and stop driving the drive source 18.

Next, the other corner portion is hardened with a laser beam by the same operation as described above. From then on,
By sequentially moving the table 3 in the X direction by the first drive device, the eccentric portion is positioned and the corner portion is hardened.

(2) Next, a specific configuration of the present invention will be explained.

FIG. 5 shows a block diagram representing an example of the configuration of the present invention.

In the figure, the laser hardening apparatus connects a central processing unit (hereinafter referred to as CPU) 50 via a main bus 50a to a display 51 with a keyboard, its input/output port 51a, and a machining program 52 incorporating various machining conditions. , a file 53 incorporating data such as laser head coordinate values and overrides, a Y-axis control servo motor 54 which is a fifth drive device that drives the table in the front-rear direction, that is, the Y-axis direction for circular interpolation, and its amplifier 54a. and an interpolator 54b, and a rate multiplier 5 representing the number of pulses generated per second.
5a, FP synchronization 55 to synchronize with interpolator 54b
an FP (feed pulse) control unit 55 that performs √2 control, and a Z-axis control servo motor 56 that is a first drive device that drives the laser head 7 in the vertical direction, that is, in the Z-axis direction for circular interpolation; The amplifier 56a and the interpolator 56b,
A rate multiplier 57a that represents the number of generated pulses per second, and an F.
FP consisting of P synchronization 57b and performing √2 control
(feed pulse) control unit 57, A-axis control servo motor 58 (drive source 21) that rotates the rotation axis (A-axis) for linear interpolation, and its amplifier 5.
8a, an interpolator 58b, a rate multiplier 59a that represents the number of generated pulses per second, and an F/P synchronizer 59b that synchronizes with the interpolator 58b. ) The control unit 59 and the FP
It is constructed by incorporating a calculation unit 60 that calculates the speed of the rotating shaft (A-axis) input to the control unit 59.

The operation of this device configured as described above will be explained.

First, the principle will be explained based on FIG. FIG. 3 shows the trajectory of the tip of the laser head 7 and the hardening point of the eccentric portion during rotation. For example, when the rotating shaft (A-axis) of the crankshaft 6 or the like is rotated, the eccentric hardening point P rotates while drawing a locus of circular motion in a plane perpendicular to the rotating shaft (indicated by a two-dot chain line).

The laser head 7 follows the rotation of the rotation axis (A-axis), and maintains a constant distance from the tip of the laser head 7 and the eccentric part hardening point P, which is hardened.
will move on the solid line part while rotating.

In this manner, the entire circumference of the eccentric pin is hardened only after one rotation while maintaining a certain relative speed to each other.

FIG. 4 shows a flowchart showing the overall flow of the laser hardening apparatus.

In the same figure, after starting, the first step is Y.
The starting point coordinates of the laser head are determined from the axis, Z-axis, radius, angle, etc., and in the second step, the required range of circular interpolation from 0° to 360° is determined. Next, in the second step, the number of FPs (feed pulses) of the arc is determined using the following formula as an example.

(For a complete circle) F.P number = (1+√2/2)・R・4 Now, if we complete the above formula by setting R to 100, we get F.P number = (1 + √2/2) x 100 x 4 = 682.8 becomes.

Next, in the second step, a straight line is created using the FP of the arc as a reference.
Find the FP number, and in the first step, find the linear velocity using the formula shown below as an example.

Speed of A-axis = number of FPs in a straight line / number of FPs in an arc x F or speed of A-axis = length of a straight line / length of an arc x F Now, set the speed of the arc (Z, Y) to 1000 and use the above formula. When completed, the A-axis speed = 360.0/682.8 x 1000 = 52.72, which is the synchronous speed.

Next, in the second step, it is checked whether or not to change the override. For example, depending on the size of eccentric parts such as the crankshaft 6, it may not be suitable to perform heat treatment at the same speed. In such a case, it is necessary to change the rotational speed, and the speed is changed according to a diagram showing override as shown in FIG.

If it is determined that it is necessary to change the override in the second stage, it is determined in the second stage whether or not the full circle is required.If the complete circle is not necessary, the range is determined on the coordinates from the start point to the end point, and the range is determined in the second stage. Proceed. In the second stage, if a complete rotation is required, the process advances to the second stage, determines override based on the data, and advances to the second stage. In the second step, each data set so far is set, and in the second step, hardening of the corner portion of the desired eccentric portion is executed.

〔Effect of the invention〕

As described above, according to the present invention, since the laser head moves following the rotation of the workpiece, in particular,
For example, it has become possible to effectively harden workpieces that have eccentric parts, such as crankshafts. Furthermore, since the mounting angle of the mirror at the tip of the laser head can be adjusted freely, it is possible to harden a desired portion such as a corner or another portion.

In addition, because the hardening is performed using a laser, which is unprecedented, there is little thermal deformation and a constant and uniform hardening depth can be maintained. Furthermore, energy accumulation due to hardening can be removed by changing the override, making it possible to provide a laser hardening device with great utility value.

[Brief explanation of drawings]

Fig. 1 shows an overall front view of the laser processing machine used in the present invention, Fig. 2 shows an enlarged partial sectional view of the vicinity of the laser head, and Fig. 3 shows rotation of the hardening point of the laser head tip and eccentric part. Fig. 4 shows a flow chart of the present invention;
FIG. 5 shows a block diagram representing an example of the configuration of the present invention, and FIG. 6 shows a diagram representing an override. DESCRIPTION OF SYMBOLS 1...Laser processing machine, 2...Bed, 3...Table, 6...Crankshaft, 7...Laser head, 10...Laser oscillator, 13...Cylinder part, 16...Gear, 19... Drive gear, 50...
Central processing unit, 52... Machining program, 54...
... Y-axis control servo motor, 55 ... FP (field pulse) control section, 56 ... Z-axis control servo motor, 57 ... FP (field pulse) control section,
58...A-axis control servo motor, 59...FP
(field pulse) control section, 60... calculation section,
E... Eccentric part, H... Laser head tip, P...
Eccentric quenching point.

Claims (1)

[Claims] 1. In a laser processing machine equipped with a laser oscillator, a control device for the laser oscillator, and an operation panel, the laser beam oscillated from the laser oscillator is moved in a vertical direction so as to irradiate polarized light in a predetermined direction. a laser head that is rotatably mounted in a plane orthogonal to the direction of movement and that includes a mirror that irradiates the laser beam to the hardened area; and a first drive that moves the laser head in a vertical direction. a second drive device for rotationally indexing the laser head; a second drive device having a first axis of rotation in a direction perpendicular to the direction of movement of the laser head and eccentrically parallel to the rotation axis; a table on which a workpiece having a second axis is mounted; a third drive device that rotates the workpiece on the table around the rotation axis; and a third drive device that moves the workpiece on the table in the axial direction of the rotation axis. a fifth driving device that moves the table in a direction perpendicular to the axial direction of the rotating shaft and the vertical movement direction of the laser head; and a workpiece eccentric part that rotates about the rotating shaft. When hardening the second shaft and the periphery of the shaft end, the third drive device rotates the workpiece while the first drive device and the fifth drive device operate to move the laser head to the workpiece. A hardening point irradiated by a laser head that is shifted in position relative to the object and maintained in the same direction draws a circular locus eccentric to the rotational axis of the workpiece by an amount equivalent to the axis diameter of the second axis. A laser hardening device consisting of a control section that performs circular interpolation control.