JPS63124747A - Rotor for high-speed rotary electric machine - Google Patents

Abstract

PURPOSE:To prevent a connecting part between a short-circuit ring and a secondary conductor from generating a crack upon high-speed rotation, by a method wherein a reinforced molding frame abuts against and fixed to both end surfaces of a rotor core and a space, formed at the inside of the frame, is filled with aluminum to form the short-circuit ring, equipped with a projection, integrally with the rotor core. CONSTITUTION:Reinforced molding frames 4a1, 4b1 abuts against both end surfaces of a rotor 1 and are fixed thereto by bolts 14 and nuts 15. These molding frames 4a1, 4b1 are provided with a space 22 at the inside thereof, a down gate 12 and a vent hole 13. Molten aluminum is cast into the space 22 through the down gate 12 and the short-circuit rings 3a1, 3b1, which are equipped with projections and integral with the frames 4a1, 4b1, are formed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Field of Application) The present invention relates to improving the retention of short-circuit rings formed on both end faces of a rotor core of a high-speed rotating N machine.

(Prior Art) As shown in Fig. 4, the rotor of a conventional high-speed rotating electric machine has a rotor core 1 laminated to a predetermined thickness, a secondary conductor 2 mainly made of aluminum material, and a rotor core 1 that is laminated to a predetermined thickness. It has short circuit rings 3a and 3b on both end faces. These short circuit rings 3a and 3b
form a taber, and reinforcing plates 4a and 4b, which are also made of a taber, are used to match the taber and the short circuit ring 3a.
and holding down 3b. The rotor core 1 and reinforcing plates 4a and 4b are shrink-fitted to the shaft 5, and a screw 6 is further attached to the shaft 5.
Screw together the nuts 7a and 7b where you cut the shaft 5.
The reinforcing plates 4a and 4 are supported by the large shaft diameter portion 8 which is a part of the
b, the shorting rings 3a and 3b and the rotor core 1 are held down in the axial direction by nuts 7a and 7b. Further, a rotor 20 for high speed rotation [5] comprising bearings 9a and 9b attached to both sides of the shaft 5 is disclosed in Japanese Utility Model Application Publication No. 49-42404.

The rotor 20 formed in this manner is supported by the tapered fitting portions of the reinforcements ff1la and 4b against the short circuit rings 3a and 3b popping out in the outer circumferential direction due to centrifugal force due to high speed rotation.

(Problems to be Solved by the Invention) However, in the above-described structure, the side surfaces of the short-circuiting rings 3a and 3b are tapered to provide reinforcement against the short-circuiting rings 3a and 3b popping out due to centrifugal force, and the reinforcing plate 4a and 4b taber processing must be applied.

The above-mentioned taper processing has the drawback that it requires high precision processing and long processing time.

In addition, if the machining accuracy is poor and the tapered shapes of the shorting rings 3a and 3b do not match the tapered shapes of the reinforcing plates 4a and 4b, and there is a slight gap, a short circuit may occur at the gap due to centrifugal force during high speed rotation. There is a drawback that cracks occur at the joints between the rings 3a and 3b and the secondary conductor 2, and furthermore, they are susceptible to breakage.

Further, it is necessary to machine the screw 6 on the shaft 5, and stress concentration at the torsion 6 reduces the rotational torsional allowable stress of the shaft 5 during high-speed rotation, resulting in fatigue failure after long-term operation.

The present invention improves the above-mentioned drawbacks by fixing reinforcing plates with overlaid short-circuit ring molds on both end faces of the rotor core laminated to a predetermined thickness with bolts, and one side of the short-circuit ring molds. One lagoon is provided in the mold, and a gas vent hole is provided in the other mold. Molten aluminum is injected from the sprue under moderate pressure conditions, and the secondary conductor and short-circuit ring are molded as one piece, which is suitable for high-speed rotation. It is an object of the present invention to provide a rotor for a high-speed rotating electric machine that can prevent a short-circuit ring from jumping out in the outer circumferential direction due to centrifugal horns.

[Structure of the Invention] (Means for Solving the Problem) In order to solve this problem, the present invention provides fI! One end of the single-layered rotor core is brought into contact with a reinforcing plate that also serves as a mold, in which a mold for short-circuiting 11 with a sprue is stacked, and the other end serves as a reinforcing plate that also serves as a mold for a short-circuiting ring having a gas vent hole. The plates are brought into contact with each other, and the laminated rotor core is tightened with multiple bolts to the reinforcing plate that also serves as a mold for the short I8 rings at both ends, and molten aluminum is poured from the sprue under moderate pressure conditions. A rotor core made by integrally molding a secondary conductor and a protruding short-circuit ring by injection is shrink-fitted to the shaft.

(Function) The function of the rotor of the high-speed rotating electric machine configured as described above will be explained. The reinforcing plate, which also serves as a forming mold for the short-circuit ring that is fixed in contact with both ends of the rotor core laminated to a predetermined thickness, is used to form the short-circuit ring with projections when molten aluminum is injected from the sprue. When the resulting rotor is operated at high speed, it serves the purpose of reinforcing the protruding short-circuit ring to prevent it from popping out in the circumferential direction due to the centrifugal force of high-speed rotation.

(Example) Examples of the present invention will be described below with reference to the drawings. 1st
The figure is a cross-sectional view of a rotor of a high-speed rotating electrical machine showing an embodiment of the present invention, and FIG. 2 is a cross-sectional view for explaining an example of a rotor casting manufacturing method. However, the same parts as in the prior art will be denoted by the same reference numerals and detailed explanations will be omitted. As shown in FIGS. 1 and 2, a large number of rotor blanks 10 are inserted into the core metal 11 to form a stacked state, and a space 22 in which a short-circuit ring 3a1 with projections is formed on the end face of the stacked rotor core 1. and a reinforcing plate 4al which also serves as a mold and has a sprue 12 is brought into contact with the reinforcing plate 4al. - On the other end surface, a space 22 forming a short circuit ring 3b1 with a protrusion and a gas vent hole 1 are provided.
3 is brought into contact with the reinforcing plate 4b1 which also serves as a mold, and is tightened and fixed with a plurality of bolts 14 and nuts 15, and the lower mold 16, middle mold 17. The mold is closed with the upper mold 18.

Next, molten aluminum is injected from the sprue 12 under moderate pressure conditions to integrally mold the protruding short-circuit rings 3a1 and 3bl and the secondary conductor 2. In this case, when molten aluminum is injected from the sprue 12, it sequentially ascends through the space 22 forming the protruding short-circuit ring 3al of the mold reinforcing plate 4al and the slot 19 of the rotor plate 10, thereby reinforcing the mold and reinforcing the mold. The space 22 forming the protruding short-circuit ring 3bl of the plate 4bl is filled. The aluminum cast into the sprue 12 and the gas vent hole 13 forms protrusions on the short-circuit rings, forming protrusion-equipped short-circuit rings 3a1 and 3b1. The formed rotor 21 is then shrink-fitted onto the shaft 5, and bearings 9a and 9b are attached to both ends of the shaft 5.

The operation of the rotor 21 of each high-speed rotation type configured in this way will be explained. The reinforcing plates 4al and 4bl, which also serve as forming molds, have spaces 22 on both end faces of the stator core 1 to form short-circuit rings 3al and 3bl with protrusions, which are fastened with a plurality of bolts 14 and nuts 15. When pouring from the sprue 12, use the short-circuit rings 3a1 and 3bl with protrusions.
It plays the role of a mold for molding. In addition, when the rotor 21 is operated at high speed, the short circuit ring 3 with protrusions is generated due to the centrifugal force of the high speed rotation.
This serves as reinforcement to prevent a1 and 3b1 from popping out in the circumferential direction.

Since the spaces 22 forming the protruding short-circuit rings 3a1 and 3b1 of the reinforcing plates 4a1 and 4bl, which are fixed in contact with both ends of the rotor core 1, are filled with molten aluminum and solidified, the protruded short-circuit rings 3a1 and 3b1 do not need to be processed into a tapered shape. In addition, the short-circuiting rings 3a1 and 3b1 with protrusions and the reinforcing plates 4al and 4bl, which also serve as molds, are filled with aluminum without any gaps, and the joint portions of the short-circuiting rings 3a1 and 3bl with protrusions and the secondary conductor 2 are filled by centrifugal force during high-speed rotation. No cracks will occur.

4al and 4bl for reinforcing molds are multiple bolts 1
4 and nuts 15, and since the rotor core 1 is shrink-fitted to the shaft 5, the reinforcing plates 4a1 and 4b1, which also serve as molds, are held in the shaft 5 in the axial direction. The screw 6 and the large shaft diameter part 8 are no longer required, and the screw machining of the shaft 5 is eliminated, stress concentration at the threaded portion is eliminated, and the allowable rotational torsional stress of the shaft 5 during high-speed rotation is increased, resulting in high-quality rotation of electrical machinery. child can provide.

Further, since the large diameter portion 8 of the shaft 5 is not required, the maximum diameter of the shaft 5 can be reduced, and the material of the shaft 5 can be saved. Furthermore, the rotor core 1 can be fixed in any position by shrink fitting,
The shaft 5 can be used in common regardless of the stacking thickness of the rotor core 1, and the shaft 5 can be standardized.

FIG. 4 shows an embodiment of the bale, in which molten aluminum is injected into the rotor by a low-pressure casting method, and a special mold is not required.

[Effects of the Invention] According to the present invention, a reinforcing plate that also serves as a forming mold and has a space therein for forming a shorting ring with a protrusion is fixed in contact with both end faces of the rotor core with bolts and nuts, and aluminum is inserted into the space. Since the short-circuiting ring with protrusions is integrally molded to meet the above requirements, there is no need to process the short-circuiting ring into a tabular shape.The short-circuiting ring with protrusions and the reinforcing plate are filled with aluminum without any gaps, and the short-circuiting ring is formed by the centrifugal force during high-speed rotation. It is possible to provide a rotor that is free from the risk of cracks occurring at the joint portion between the main conductor and the secondary conductor.

[BRIEF DESCRIPTION OF THE DRAWINGS] Fig. 1 is a sectional view of a rotor of a high-speed rotating electric machine showing an embodiment of the present invention, and Fig. 2 is a sectional view illustrating an example of a method for manufacturing a rotor of the present invention. , FIG. 3 is a diagram corresponding to FIG. 2 of the relaxed embodiment of the present invention, and FIG. 4 is a diagram corresponding to FIG. 1 of the prior art. 1... Rotor core, 2... Secondary conductor, 3a1.3
b1... Short circuit ring with protrusion, 4a1.4b1... Reinforcement plate that also serves as mold, 12... Sprue, 13... Gas vent hole, 19... Slot,
20.21...Rotor, 22...Space.

Claims (1)

[Claims] In a rotor of a high-speed rotating electrical machine that has a short-circuit ring and a secondary conductor formed by casting a conductive material into the slots of the rotor core, a space in which a short-circuit ring with protrusions is formed inside and a sprue communicating with this space. A reinforcing plate that also serves as a forming mold and has a gas vent hole is brought into contact with both end faces of the rotor core, and is tightened and fixed, and a conductive material is cast into the space, the sprue, the gas vent hole, and the slot of the rotor core to form a short-circuit ring with protrusions. A rotor for a high-speed rotating electric machine characterized by integrally molding a secondary conductor and a secondary conductor.