JPH10225068A - Method of manufacturing rotor core for AC rotating electric machine - Google Patents

Abstract

(57) [Problem] To provide a method of manufacturing a rotor core for an AC rotating electric machine, which is easy to manufacture and can greatly reduce a processing step and processing steps. SOLUTION: In a method of manufacturing a crown-shaped rotor core for an AC rotating electric machine, a plurality of magnetic pole pieces are integrally protruded from one end surface of a hollow cylindrical body in parallel with an axis of the hollow cylindrical body. By using a plate material having the same thickness, a material is formed on the inner edge of the hollow disk portion by radially and integrally projecting a plurality of trapezoidal pole pieces toward the inside of the hollow disk portion, The hollow disk portion of this material is drawn through a press forming means to form a crown having a hollow cylindrical body having an inner diameter substantially equal to the inner diameter of the hollow disk.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a rotor core for an AC rotating electric machine, and more particularly to a rotor core 2 having a plurality of comb-shaped magnetic pole pieces integrally projecting from an outer peripheral portion thereof in parallel with an axis. The present invention relates to a method for manufacturing a rotor core for an AC rotating electric machine, in which the magnetic pole pieces are arranged so as to enter each other between opposing magnetic pole pieces, and the two rotor cores are integrally formed.

[0002]

2. Description of the Related Art FIG. 5 is a longitudinal sectional view of an essential part showing an example of a conventional rotor for an AC rotary electric machine. In FIG. 5, reference numerals 1 and 2 denote rotor cores, each of which is made of a soft magnetic material such as S10C and has a plurality of magnetic pole pieces 3 provided integrally on an outer peripheral portion as described later. Reference numeral 4 denotes a boss portion, which is provided integrally with the center portion of the rotor core 2 and has a shaft hole 4a formed in the boss portion 4. Reference numeral 5 denotes a ring, which is formed of a non-magnetic material such as stainless steel. Then, after this ring 5 is fitted to the inner peripheral surface of the pole piece 3 of the rotor core 2, the magnetic pole piece 3 of the rotor core 1 is coaxially combined with the pole piece 3 of the rotor core 2 being inserted between the pole pieces 3, 3.

[0003] Next, the rotor cores 1 and 2 and the ring 5 are integrally fixed by welding the ring 5 and the pole piece 3 to each other. Reference numeral 6 denotes a shaft, which is formed of a structural material such as S48C, for example, and is pressed into a shaft hole 4a of the boss portion 4 of the rotor core 2 to be fixed.
In this case, if the shaft 6 is knurled at the fitting portion with the shaft hole 4a and then subjected to, for example, induction hardening, it is convenient to secure the fixing strength to the rotor core 2.

FIGS. 6 and 7 are perspective views showing the rotor cores 1 and 2 in FIG. 5, respectively, and the same parts are denoted by the same reference numerals as in FIG. 6 and 7, the pole pieces 3 are integrally formed on the outer peripheral portions of the rotor cores 1 and 2 in a trapezoidal and comb-teeth shape extending in a direction parallel to the axis.
Provide at equal intervals in the circumferential direction. Reference numerals 3a and 3b denote locking portions and fitting portions, respectively, for locking and fitting the ring 5 shown in FIG. 5, and are formed by machining means such as turning.

FIGS. 8 and 9 are perspective views showing steps of manufacturing the rotor cores 1 and 2, respectively. First, in FIG.
A short columnar raw material 1a having a predetermined size as shown in (a) is formed by hot forging to obtain a crown-shaped formed body 1b as shown in (b). 1c is a forged burr formed by forging. Next, unnecessary forging burrs 1c are punched out by trimming to obtain the rotor core 1 as shown in FIG.

Next, in FIG. 9, similarly to the one shown in FIG. 8, a short columnar material 2a having a predetermined size as shown in FIG. 8A is formed by hot forging, and as shown in FIG. After obtaining the molded body 2b, unnecessary forged burrs 1c are punched out by trimming as shown in FIG.

After the rotor cores 1 and 2 are formed, the pole pieces 3
Then, the rotor cores 1 and 2 are formed by reshaping and correcting a predetermined portion by machining.

[0008]

As described above, it is impossible to form the rotor cores 1 and 2 into their final shapes by hot forging, and the forged product is relatively large even by die forging. Draft and finish are required. In the forging process before the die forging, the boss 4 and the plurality of pole pieces 3 need to be protruded, so that not only skill is required for the forging operation but also a large amount of time and man-hours are required because of the complexity. There is a problem that.

[0009] Since the size variation after molding is large and the finishing margin is large as described above, the time and man-hour required for machining are also large, and a large amount of chips are generated. There is also a problem that the environment is deteriorated and the work of processing chips is complicated.

An object of the present invention is to provide a method of manufacturing a rotor core for an AC rotary electric machine which solves the above-mentioned problems in the prior art, is easy to manufacture, and can greatly reduce the number of processing steps and processing steps. Aim.

[0011]

In order to solve the above-mentioned problems, according to the present invention, a plurality of magnetic pole pieces are integrally protruded from one end face of a hollow cylinder in parallel with the axis of the hollow cylinder. In the manufacturing method of the crown-shaped rotor core for AC rotating electric machine, the plate material of equal thickness dimension made of a magnetic material,
A material formed by projecting a plurality of trapezoidal pole pieces radially and integrally toward the inside of the hollow disk portion is formed on the inner edge of the hollow disk portion, and the hollow disk portion of the material is formed. By press forming through a press forming means to form a crown having a hollow cylindrical body having an inner diameter substantially equal to the inner diameter of the hollow disk portion.

In the present invention, the length of the pole piece along the axial direction of the hollow cylinder can be formed larger than the length of the hollow cylinder in the axis direction. In the above invention, a punching process or a laser process can be adopted as a material forming means.

[0013]

1 and 2 are a plan view showing a material of a rotor core 1 and a perspective view showing the rotor core 1 according to an embodiment of the present invention, and the same parts are shown in FIGS. 8 are denoted by the same reference numerals. First, Figure 1
In the figure, reference numeral 10 denotes a raw material, for example, a plurality of trapezoidal pieces (FIG. 1) formed on the inner edge of the hollow disk portion 11 by stamping a plate material of equal thickness made of S10C into the hollow disk portion 11. The six magnetic pole pieces 3 are stamped and formed in a radially and integrally projecting shape at equal intervals in the circumferential direction.

The thickness of the plate material forming the material 10 is set to a size through which a magnetic flux required for the rotor core 1 shown in FIG. 5 can pass. The length of the pole piece 3 in the radial direction is preferably larger than the width of the hollow disk portion 11 in the radial direction.

Next, the blank 10 shown in FIG. 1 is formed into a crown-shaped rotor core 1 as shown in FIG. 2 by a press molding die. That is, the magnetic pole piece 3 of the material 10 shown in FIG. 1 is erected, and the hollow disk portion 11 is drawn to form a hollow cylindrical body 12 as shown in FIG. In this case, it is preferable that the inner diameter of the hollow cylindrical body 12 is formed to be substantially equal to the inner diameter of the hollow disk portion 11 shown in FIG.

The length of the hollow cylindrical body 12 in the axial direction is substantially equal to the width of the hollow disk portion 11 in the radial direction shown in FIG. The connection between the pole piece 3 and the hollow cylindrical body 12 or the hollow disk portion 11 shown in FIG. 1 is preferably provided with a slight roundness in order to facilitate the manufacture of a punching die. It is preferable to avoid stress concentration at the time.

FIGS. 3 and 4 are a plan view and a perspective view, respectively, showing the material of the rotor core 2 according to the embodiment of the present invention.
9 and the same reference numerals as those in FIG. First, in FIG. 3, reference numeral 20 denotes a raw material. For example, a plate material having an equal thickness made of, for example, S10C is punched toward the outer edge of the hollow disk portion 21 having the hole 22 by using a punching die. A plurality of trapezoidal pole pieces 3 (six in FIG. 3) are stamped and formed into radially and integrally protruding shapes at equal intervals in the circumferential direction.

The thickness of the plate material forming the material 20 is set to a size that allows the magnetic flux required for the rotor core 2 shown in FIG. 5 to pass, similarly to the material 10 shown in FIG. The outer diameter of the hollow disk portion 21 is formed to be substantially equal to or slightly smaller than the inner diameter of each of the hollow disk portion 11 and the hollow cylindrical body 12 shown in FIGS. . Further, the connection between the hollow disk portion 21 and the pole piece 3 is provided with a slight roundness in order to facilitate the manufacture of the punching die and to avoid stress concentration during the molding process described later. preferable.

Next, the blank 20 shown in FIG. 3 is formed into a crown-shaped rotor core 2 as shown in FIG. 4 by a press molding die. That is, the magnetic pole piece 3 of the material 20 shown in FIG.
The boss portion 4 formed by drilling the shaft hole 4a in a round bar made of is joined to the hollow disk portion 21. As the joining means, known means such as press fitting, welding, shrink fitting and the like can be used.

After molding the rotor cores 1 and 2 as described above,
As shown in FIGS. 6 and 7, the locking portion 3a and the fitting portion 3b are formed on the inner peripheral surface of the magnetic pole piece 3 by turning to obtain a rotor for an AC rotating electric machine as shown in FIG. is there. As a result of operating the rotor thus formed in an AC rotating electric machine, it was confirmed that sufficiently satisfactory characteristics could be exhibited.

In the above embodiment of the present invention, the example in which the blanks 10, 20 of the rotor cores 1, 2 are formed by stamping has been described. However, the blanks may be formed by laser machining using NC control means. According to such means, there is an advantage that it is possible to immediately cope with a local specification change of the rotor core. The boss portion 4 constituting the rotor core 2 may be a solid round bar lacking the shaft hole 4a at the time of joining with the hollow disk portion 21, and the shaft hole 4a may be formed after joining. Further, the number of the pole pieces 3 and the thickness dimensions of the rotor cores 1 and 2 can be appropriately selected according to the specifications of the AC rotating electric machine.

[0022]

Since the present invention has the configuration and operation as described above, the following effects can be obtained.

(1) Since the material of the rotor core is formed of a plate material having an equal thickness, the processing is easy, and the processing time and the number of processing steps can be reduced. (2) Variations in dimensions of each part of the rotor core are small, and high accuracy can be achieved.

(3) Since the raw material dimensions can be approximated to the final finished dimensions, the finishing margin is small, machining is easy, and the generation of chips is small, which can contribute to environmental improvement.

[Brief description of the drawings]

FIG. 1 is a plan view showing a material of a rotor core 1 according to an embodiment of the present invention.

FIG. 2 is a perspective view showing a rotor core 1 according to the embodiment of the present invention.

FIG. 3 is a plan view showing a material of a rotor core 2 according to the embodiment of the present invention.

FIG. 4 is a perspective view showing a rotor core 2 according to the embodiment of the present invention.

FIG. 5 is a longitudinal sectional view of a main part showing an example of a conventional rotor for an AC rotating electric machine.

FIG. 6 is a perspective view showing the rotor core 1 in FIG.

FIG. 7 is a perspective view showing the rotor core 2 in FIG.

FIG. 8 is a perspective view showing a manufacturing process of the rotor core 1.

FIG. 9 is a perspective view illustrating a manufacturing process of the rotor core 2.

[Explanation of symbols]

 1, 2 rotor core 3 pole piece

Claims (4)

[Claims] 1. A method for manufacturing a crown core-shaped rotor core for an AC rotating electric machine, comprising a plurality of magnetic pole pieces integrally projecting from one end surface of a hollow cylindrical body in parallel with an axis of the hollow cylindrical body. A material formed by projecting a plurality of trapezoidal pole pieces radially and integrally toward the inner side of the hollow disk portion on the inner edge of the hollow disk portion by using a plate material having an equal thickness dimension made of The hollow disk portion of this material is drawn through a press forming means to form a crown having a hollow cylindrical body having an inner diameter substantially equal to the inner diameter of the hollow disk. Of manufacturing a rotor core for an AC rotating electric machine. 2. The rotor core for an AC rotary electric machine according to claim 1, wherein the length of the pole piece along the axial direction of the hollow cylindrical body is formed larger than the length of the hollow cylindrical body in the axial direction. Manufacturing method. 3. The method for manufacturing a rotor core for an AC rotary electric machine according to claim 1, wherein the material forming means is punching. 4. The method for manufacturing a rotor core for an AC rotary electric machine according to claim 1, wherein the material forming means is laser processing.