JP2701048B2 - Rotor and its manufacturing method - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotor of a rotating machine such as a motor or a generator, and more particularly to a rotor having an improved shaft hole condition and a method of manufacturing the same.

[Related Art] A rotating machine such as an electric motor or a generator generally includes a substantially cylindrical rotor and a stator surrounding the rotor. FIG. 4 is a perspective view for conceptually explaining an example of the configuration of the rotor. Reference numeral 2 denotes a cylindrical laminated iron core, and reference numeral 4 denotes a shaft press-fit into a shaft hole 6 of the laminated iron core. .

The shaft hole 6 is formed coaxially through the center of the laminated iron core 2, and the shaft 4 pressed into the shaft hole 6 becomes coaxial with the laminated iron core 2. The laminated iron core 2 is formed by coaxially laminating and integrating circular iron plates 2a formed by punching an electric iron plate such as a silicon steel plate into a disk shape.

The circular iron plate 2a is formed, for example, by punching a silicon steel plate by a punching press or the like, first punching a hole having the same diameter as the shaft hole 6 at a central position, and then punching a substantially disk-shaped outer shape around this hole. It is formed by punching out sequentially with a punching press. The shaft hole 6 is formed by laminating the circular iron plates 2a manufactured in this way and connecting the central holes thereof to one.

The shaft 4 is inserted into the shaft hole 6 of the laminated iron core 2.
By press-fitting in the direction of arrow A (see FIG. 4). FIG. 5 is a sectional view showing an internal state of the rotor formed by press-fitting the shaft 4 into the shaft hole 6 of the laminated iron core 2, and the shaft 4 is coaxially fixed to the laminated iron core 2.

[Problems to be Solved by the Invention] In the conventional rotor and the method for manufacturing the same as described above, when the shaft is press-fitted into the shaft hole of the laminated iron core, the shaft is galled depending on the size of the press-fitting allowance of the shaft hole. May occur or the laminated iron core may be deformed, so after press punching, the shaft hole must be shaved with a reamer or broach, and the press-fit allowance must be post-processed to an appropriate size. There was a problem.

In addition, when laminating circular iron plates based on the shaft hole, the outer periphery of the rotor becomes uneven, and the outer periphery must be cut by post-processing in order to maintain the gap between the stator and the rotor. was there.

Further, when the cross-sectional shape of the shaft hole 6 is a spline shape as shown in FIG. 6 or 7, no post-processing for press-fitting is required, but the tolerance of the inner diameter φA is extremely strict. However, processing into such a shape itself is extremely troublesome, and there is a problem that the shaft must also be processed into a shape corresponding to this.

The present invention has been made in order to solve these problems, and an object of the present invention is to provide a rotor in which a shaft is press-fitted and fixed in a shaft hole and a method of manufacturing the same.

[Means for Solving the Problems] A rotor according to the present invention includes a laminated iron core having a central shaft hole, and a shaft fitted in the shaft hole, and the laminated iron core has a hole. A plurality of circular iron plates are laminated and integrated in a columnar shape based on the outer diameter, and the center of the hole is offset from the center based on the outer diameter of the circular plate by a predetermined distance δ in the radial direction. The line connecting the center of the hole and the center based on the outer diameter of the circular iron plate is shifted by a predetermined angle between adjacent circular iron plates in the rotation direction, and the hole is formed by laminating the circular iron plates. The inner surface of the shaft hole has a step formed by the inner peripheral edge of the hole of the iron plate, and the inner diameter of the hole formed by the protrusion of the step is equal to the outer diameter of the shaft or The above problem has been solved by increasing the size.

Here, it is preferable that the predetermined angle is 360 ° / M (M = 2 to 8).

Further, the method for manufacturing a rotor according to the present invention is characterized in that a hole that is laminated to form a shaft hole is formed in an iron plate, and the iron plate formed with the hole is punched into a disk shape by using a die. A method in which a circular iron plate formed by punching in a shape is pressed into the die to be laminated and integrated in a columnar shape to form a laminated core, and a shaft is fitted into a shaft hole of the laminated core. When punching, the center of the hole is deviated by a predetermined distance δ from the center axis of the die, and every time the iron plate is punched and a circular iron plate is laminated, the die is shifted by a predetermined angle about the center axis thereof. The above problem is solved by rotating.

[Operation] In the present invention, since the center of the hole of the circular iron plate is displaced by a predetermined distance δ in the radial direction from the center of the shaft hole at every predetermined angle, the inner surface of the shaft hole of the laminated iron core is regularly arranged. A step is formed, the area of the shaft hole that comes into contact with the shaft when the shaft is inserted into the shaft hole is reduced, and the frictional resistance when the shaft is inserted into the shaft hole of the laminated iron core is reduced.

Also, since the center of the hole of the circular iron plate is deviated by a predetermined distance δ in the radial direction from the center of the shaft hole at a predetermined angle, the center of gravity of each circular plate is uniformly distributed around the center axis of the shaft hole. , The center of gravity of the laminated iron core coincides with the center of the shaft hole.

FIG. 1 is a perspective view showing an example of a laminated iron core of a rotor according to the present invention. A laminated iron core 2 of a rotor is formed by a circular iron plate 2a having a hole in the center and a central axis 8 of a shaft hole 6. (See FIG. 2). The layers are sequentially rotated while being shifted by 90.degree.

FIG. 2 is a plan view showing the rotor laminated iron core 2 viewed from above, where a point 10a is the center of the top circular iron plate 2a, a point 10b is a center of the second circular iron plate 2a from the top, Point 10c is the center of the third circular iron plate 2a from the top, and point 10d is the center of the fourth circular iron plate 2a from the top.

The circular iron plates 2a are thus laminated while being sequentially rotated, and the amount of deviation of the center of the circular iron plate 2a with respect to the central axis 8 of the shaft hole 6 is indicated by δ in FIG.

The diameter D ₁ of the shaft hole 6 of the laminated iron core 2 is a cylindrical space 12 having a diameter D ₂ formed by passing the circular iron plates 2a from top to bottom when they are laminated.
As the shaft 4 of the diameter D ₃ is sized to better fit the slightly larger-formed laminated rotor iron core 2 as described above are can be prepared, for example, as follows .

First, at the time of press punching, the hole to be the shaft hole 6 is punched by shifting in a predetermined direction by δ from the position to be the central axis 8 in the subsequent outer diameter punching step, and then, in the outer diameter punching step, Before punching, the laminated iron core that has been punched out and laminated into the die is 360 ゜ / M
After being rotated (an integer of 8), the outer diameter is punched out, and the formed circular iron plate 2a is sequentially laminated on the laminated iron core in the rotated die. Thereby, a regular step is formed on the inner surface of the shaft hole 6 (see FIG. 1).

Next, when the adhesive 14 is injected into the gap between the shaft 4 and the shaft hole 6 and left for a predetermined time, the adhesive 14 is solidified and the shaft 4 is fixed to the shaft hole 6 as shown in FIG. You. As described above, the adhesive 4 is poured into the gap between the shaft 4 and the shaft hole 6 so that the shaft 4 is connected to the shaft hole 6 of the laminated iron core 22.
Can be fixed easily.

The amount of deviation δ of the hole in the circular iron plate 2a needs to be an amount in which the adhesive 14 works most effectively, but this is adjusted when the mold is manufactured.

Further, in the above description, the rotation of the circular iron plate 2a is 360 ° / M
(M is an integer of 2 to 8), but the rotation of the iron plate 2a is not limited to this, and a normal skew angle (for example, 3 ° or other small angle) performed to improve electric characteristics It is also possible to manufacture a laminated iron core by rotating it by minutes.

[Effect of the Invention] Since the present invention is configured as described above, a regular step is formed on the inner surface of the shaft hole of the laminated iron core, and when the shaft is inserted into the shaft hole, the shaft hole contacts the shaft. The area is reduced, the frictional resistance when the shaft is inserted into the shaft hole of the laminated iron core is reduced, and the press-in allowance can be reduced as much as possible in the process of pressing the shaft into the iron core for the rotor. This has the effect of increasing the quality of the steel, reducing the defect rate, and eliminating the need for correcting (post-processing) the shaft hole.

In addition, since the centers of the holes of the circular iron plates are laminated by being shifted by a predetermined distance δ in the radial direction from the center of the shaft hole at predetermined angles, that is, the circular iron plates are rotated and stacked, so that the center of gravity of each circular iron plate is It is uniformly distributed around the center axis of the hole, and the center of gravity of the laminated iron core coincides with the center of the shaft hole, thereby improving the balance of the laminated iron core and contributing to a reduction in rotor manufacturing cost.

Further, in the present invention, since the circular iron plates are laminated on the basis of the outer diameter, there is an effect that the outer periphery need not be cut by post-processing in order to form a gap with the stator.

[Brief description of the drawings]

1 is a perspective view of a laminated core of a rotor according to the present invention, FIG. 2 is a plan view of FIG. 1, and FIG. 3 is a cross section of the rotor formed by inserting a shaft into that of FIG. Fig. 4 is an exploded perspective view of a conventional rotor, Fig. 5 is a cross-sectional view of the conventional rotor, and Figs. 6 and 7 show examples of the shape of the shaft hole of the conventional laminated iron core. FIG. 2 ... Laminated iron core, 2a ... Circular iron plate, 4 ... Shaft, 6 ...
… Shaft hole, 8… Center axis, 10a, 10b, 10c, 10d… Center, 12
…… Cylindrical space, 14… Adhesive, D ₁ , D ₂ , D ₃ …… Diameter, δ
...... The amount of deviation.

Claims (4)

(57) [Claims] 1. A laminated iron core having a shaft hole at the center thereof, and a shaft fitted into the shaft hole, wherein the laminated iron core is formed by forming a plurality of circular iron plates having holes into circles based on an outer diameter. The center of the hole is deviated by a predetermined distance δ in the radial direction from the center based on the outer diameter of the iron plate, and the center of the hole and the outer diameter of the iron plate The line connecting the center with respect to is shifted in the rotational direction by a predetermined angle between the adjacent circular iron plates, the hole forms a shaft hole by laminating the circular iron plates, and the inner surface of the shaft hole has A rotor having a step formed by an inner peripheral edge of a hole of the circular iron plate, and an inner diameter of a hole formed by a protrusion of the step is equal to or larger than an outer diameter of the shaft. 2. The rotor according to claim 1, wherein the predetermined angle is 360 ° / M (M = 2 to 8). 3. The rotor according to claim 1, wherein the predetermined angle is an angle corresponding to a skew amount. 4. A hole formed in an iron plate, which is laminated to form a shaft hole, and the iron plate having the hole formed therein is punched into a disk shape by using a die, and is also formed by punching into a disk shape. A method in which a circular iron plate is pushed into the die to be laminated and integrated in a columnar shape to form a laminated core, and a shaft is fitted into a shaft hole of the laminated core. Is deviated by a predetermined distance δ from the central axis of the die, and the die is rotated by a predetermined angle about the central axis each time the iron plate is punched and a circular iron plate is laminated. Rotor manufacturing method.