JPS6256746B2 - - Google Patents

Description

[Detailed description of the invention] (1) Object of the present invention When adjusting the balance of a rotating body such as a motor rotor using a laser beam, etc., it is possible to prevent temperature rise and burr generation on the rotating body as a workpiece. The purpose is to provide a method for adjusting the balance of the body.

(2) Disadvantages of the conventional example The present invention detects the unbalance caused by rotation, and removes material from the rotating body by irradiating it with a laser beam or the like while the rotating body is rotating. The present invention relates to a method for adjusting the balance of a rotating body by correcting the unbalance of the rotating body.

In recent years, there has been a trend for rotating bodies, such as small motors, to be smaller, with higher output, and faster rotation. For example, improvements in performance and functionality can be seen in devices that use fans, such as hair dryers and cleaners, by increasing the proportion of the fan in the overall product to increase capacity, or by making the entire device smaller and thinner to make it easier to use. .
However, the higher the rotation speed, the greater the vibrations generated, which is unfavorable in terms of motor performance and life. Conventionally, therefore, the balance of the rotor has been corrected by machining, but this is inefficient and takes a long time because the rotor must be rotated and stopped each time the balance is measured and corrected.

Recently, a method has been adopted to remove and correct the balance by irradiating the rotating body with a laser beam while rotating it. This allows measurement and correction to be performed at the same time, making it possible to correct small unbalances in the rotor in a short time. There is. Among lasers, those used for processing are mainly solid lasers such as ruby, YAG, and glass lasers, and gas lasers such as carbon dioxide gas lasers.

There have been reports that attempts have been made to adjust the balance of rotating bodies such as gyroscopes and turbines using lasers. As a method for this, a method has been devised in which the laser is rotated in synchronization with a rotating body so that the unbalanced portion remains stationary relative to the laser irradiation position.

However, in order to rotate the laser synchronously with the rotating body, it is necessary to rotate the optical system, which makes the device complicated.
Therefore, a method is used in which every time an unbalanced part of a rotating body comes to the laser irradiation position, a laser pulse is irradiated to make a hole in the rotating body and material is removed in order to reduce the weight of the rotating body.

When adjusting the balance of a rotating body using a laser beam, electron beam, etc., the amount of material that can be removed with a single (one pulse) laser beam irradiation is only a few mg/pulse using a pulse oscillation laser processing machine. That's about it. Accordingly, a rotor 1 as shown in FIG. 1 was manufactured.
The initial unbalance at one point is a number
If the amount is as much as 10 mg, as shown in Figure 2, it is necessary to shift the irradiation position of laser beam 2, etc. around one unbalanced point, drill holes over a wide area, and remove unnecessary material. 3 is a coil.
As a method for this purpose, for example, as shown in FIG. 3 or FIG. 4, the irradiation position of the laser beam or the like is shifted in the direction of one rotation of the rotating body 1 or in the direction of the rotation axis, and the amount equivalent to the unbalance is removed.

As shown in FIGS. 3 and 4, this amount of shift is determined by making the irradiation positions of laser beams or the like overlap little by little so that the holes formed have an overlapping portion.

However, this method has the following drawbacks.

(b) Since the irradiation positions of laser beams, etc. are overlapped, the weight removed per pulse is reduced by the amount of overlap.

(b) The temperature of the workpiece increases. Possible reasons for this are as follows.

(1) Most of the irradiation energy for the overlap is converted into heat.

(2) Since the holes are continuous, all of the molten metal does not scatter.

(c) Due to (b)-(2) above, some of the molten material (usually metal) remains on the contour of the hole and forms a burr.

The present invention seeks to eliminate the above drawbacks. DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be explained below based on drawings showing examples.

(3) Configuration and operation of the present invention When adjusting the balance of the rotating body 1 using a laser beam, etc., the irradiation position of the laser beam, etc. is set at an unbalanced location measured by a balancer, etc., as shown in FIGS. 5 to 7. irradiate without overlapping. At this time, the irradiation pitch of the laser beam or the like is set to be equal to or larger than the beam diameter in the direction of the rotation axis of the rotating body 1, and the next hole 3 is made. Further, in the rotational direction, a laser beam or the like is irradiated at pitch intervals that are longer than the pulse width (the width of the hole created by removing material with one pulse). In other words, the irradiation position of the laser beam etc. is shifted in a honeycomb pattern, and the material corresponding to the amount of unbalance is transferred from the rotating body 1 to the rotating body 1.
Delete it as if making hole 3.

(4) Effects of the present invention In the present invention, the balance of the rotating body is adjusted as described above, so (a) the temperature rise of the workpiece is small. (This eliminates the drawbacks of the conventional method.) (B) Since a single hole is drilled per pulse of irradiation with a laser beam, etc., no burrs are generated at the location where the material is removed.

(c) Since there is no overlap in the locations where the material is removed by the laser beam, etc., the amount removed per pulse is stable, and highly accurate balance adjustment is possible.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of a rotor of a motor, Figs. Figures to Figures 7 are diagrams showing one embodiment of the present invention,
5 and 6 are perspective views of essential parts, and FIG. 7 is a sectional view.

Claims (1)

[Claims] 1 In a method for adjusting the balance of a rotating body in which the rotating body is rotated and irradiated with laser beams, electron beams, etc. to remove unnecessary materials and balance the rotating body by drilling holes in the rotating body, one of the rotating bodies such as laser beams, electron beams, etc. A method for adjusting the balance of a rotating body in which the irradiation positions for an unbalanced spot are set at a pitch greater than the beam diameter in the direction of the rotational axis, and at a pitch greater than the pulse width in the rotational direction so that the holes do not overlap.