KR20220159797A - Method for manufacturing a stacked rotor for a axial flux induction generator and a stacked rotor using the same - Google Patents

Abstract

The present invention relates to a method for manufacturing a stacked rotor for an axial flux induction generator and a stacked rotor using the same. The method for manufacturing a stacked rotor, according to the present invention, comprises: a punching step (S1); a winding step (S2); a welding step (S3); a cutting molding step (S4); a cutting step (S5); and a shaft insertion step (S6). Therefore, iron loss can be efficiently reduced.

Description

Method for manufacturing a stacked rotor for a axial flux induction generator and a stacked rotor using the same}

The present invention relates to 'a manufacturing method of a multilayer rotor for an axial induction generator and a multilayer rotor thereby' , and more particularly, after winding an iron core, the iron core is molded together with aluminum by a casting process, and then in a cutting process It relates to a 'manufacturing method of a stacked rotor for an axial induction generator and a stacked rotor thereby', characterized in that iron loss due to hysteresis and eddy current can be reduced because it is completed by

In general, an axial induction generator is used to mount in a narrow space such as a vehicle or two-wheeled vehicle. The axial induction generator is configured such that a disk-shaped rotor 1 is rotatable inside a housing, and stators corresponding to both sides of the rotor 1 are configured inside the housing. A magnet is attached to the stator so that magnetic flux is generated in an axial direction.

A general manufacturing method of the rotor 1 will be described in conjunction with the accompanying drawings.

1 is a rotor for an axial induction generator according to the background art, (a) is a plan view of an iron core manufactured by casting, and (b) is a front view of an iron core manufactured by casting, and the following process precedes first.

As shown in FIG. 1, the disk-shaped iron core 10 is manufactured by casting. At this time, it should be understood that the shaft 30 is molded without being inserted in FIG. 1 (a). The iron core 10 has a shaft hole 11 formed in the center, and slits 15 open up and down and sideways are arranged in a circumferential direction.

FIG. 2 is a plan view showing that the molded iron core is molded together with aluminum as in FIG. 1, and the following process will be described.

The molded iron core 10 is put in a mold and molten aluminum is injected to fill the slit 15 with aluminum 20, cover the upper and lower surfaces of the iron core 10 with aluminum 20, and A ring-shaped rim F is molded along the circumference.

FIG. 3 is a perspective view illustrating the completion of the rotor for an axial induction generator by cutting the iron core that has undergone the process of FIG. 2, and the following process will be described.

The upper and lower surfaces of the iron core 10 molded together with the aluminum 20 and the rim F are cut to be manufactured according to the designed dimensions. And since the shaft 30 is inserted into the shaft hole 11 and fixed, manufacturing is completed.

As described above, according to the present invention examined, there were the following problems.

Generally, in a rotor used in a radial induction generator, a shaft passes through a plurality of stacked iron cores. Also, common grooves are formed in the plurality of iron cores, and the grooves are filled with aluminum by casting. Therefore, when the rotor is applied to a radial induction generator, magnetic flux is generated in a direction perpendicular to the shaft by a stator mounted around the iron core. That is, the magnetic flux passes through the iron core through the outer end of each iron core. In this way, since the iron core is used as a plurality of stacked iron cores instead of a single shape, it is possible to reduce power loss due to iron loss, that is, hysteresis loss and eddy-current loss. .

However, in the case of an axial induction generator, magnetic flux is generated in the axial direction with respect to the rotor 1. Therefore, in order to reduce iron loss, there is a need to laminate the iron core 10 in parallel with the magnetic flux direction like the radial induction generator. That is, a plurality of thin plate-shaped iron cores must be stacked in parallel with respect to the shaft. To this end, it is necessary to overlap and combine circular iron cores of different concentric circle shapes, but it is practically impossible to individually manufacture these iron cores so that they are in close contact with each other. Therefore, as shown in FIG. 1, there was no choice but to manufacture by casting with a single iron core 10. Therefore, there is a problem in that power loss due to iron loss cannot be reduced.

Korean Patent Registration No. 10-2246697 (April 26, 2021)

Through the 'manufacturing method of a multilayer rotor for an axial induction generator and a multilayer rotor according to the same' according to the present invention, the following problems are to be solved.

In the case of an axial induction generator, magnetic flux is generated in the axial direction with respect to the rotor. Therefore, in order to reduce iron loss, there is a need to laminate iron cores in parallel with the magnetic flux direction like the radial induction generator. To this end, it is necessary to overlap and combine circular iron cores of different concentric circle shapes, but it is practically impossible to individually manufacture these iron cores so that they are in close contact with each other. Therefore, there was no choice but to manufacture it by casting with a single iron core. Therefore, there is a problem in that power loss due to iron loss cannot be reduced.

The 'method of manufacturing a stacked rotor for an axial induction generator' according to the present invention includes the following steps in order to solve the above problems.

A punching step of punching holes in a strip-shaped iron core at a pitch prescribed in the longitudinal direction, a winding step of winding the iron core discharged through the punching step in a circular shape, and welding the iron core after the winding step to prevent unwinding A welding step of inserting a hub into the center and welding it to the iron core, and cutting one side (one of the upper and lower surfaces) of the iron core after the welding step to open one side (one of the upper and lower parts) of the hole After forming slits that open outward from the center of the iron core and are arranged along the circumferential direction, insert the core into the hub of the iron core, put the slit in an upward direction, and inject molten aluminum so that the aluminum A cutting molding step of covering one side of the iron core to form an edge, performing the same process on the opposite side of the iron core, and removing the core, and cutting the upper and lower surfaces of the iron core and the edge through the cutting molding step and a cutting step of exposing the upper and lower surfaces of the iron core and forming the rim to a prescribed size, and a shaft inserting step of inserting and fixing a shaft into the hub that has undergone the cutting step.

Further, in the winding step, a step of winding the hole radially overlaps the hole may be further included.

In addition, an insulating material may be selectively attached to the upper and lower surfaces of the iron core injected in the punching step.

Next , the 'laminated rotor according to the manufacturing method of the multilayer rotor for an axial induction generator' according to the present invention is manufactured by the above process.

The 'method for manufacturing a stacked rotor for an axial induction generator' according to the present invention has the following effects by the above solution.

Due to the characteristics of an axial induction generator, magnetic flux is generated in the axial direction. Therefore, since the present invention can have a shape in which iron cores are stacked in parallel with the axial direction, iron loss can be reduced more efficiently than those formed with a single iron core as in the background art. That is, power loss due to hysterical hands and eddy current hands can be reduced. In particular, as the thickness of the iron core is reduced, the iron loss can be more effectively reduced. In addition, as shown in FIG. 6, when an insulator is interposed between iron cores, iron loss can be further reduced.

1 is a rotor for an axial induction generator according to the background art, (a) is a plan view of an iron core manufactured by casting, (b) is a front view of the iron core manufactured by casting.
Figure 2 is a plan view showing that the molded iron core is molded together with aluminum as in Figure 1;
Figure 3 is a perspective view showing that the rotor for an axial induction generator is completed by cutting the iron core that has undergone the process of Figure 2;
Figure 4 is a flow chart showing a method of manufacturing a stacked rotor for an axial induction generator according to the present invention.
Figure 5 shows the punching step and the winding step in the method of manufacturing a stacked rotor for an axial induction generator according to the present invention, (a) is a view from the top, (b) is a view from the side Illustrated process diagram.
6 is a process diagram showing that an insulating material is attached to the lower or upper surface of the iron core in the punching step and the winding step as another embodiment of the manufacturing method of the multilayer rotor for an axial induction generator according to the present invention.
7 is a process chart showing a hub insertion step, a welding step, a first cutting step and a casting step in the method of manufacturing a multilayer rotor for an axial induction generator according to the present invention.
8 is a process chart showing a casting step and a first cutting step in the manufacturing method of a multilayer rotor for an axial induction generator according to the present invention.
Figure 9 is a process chart showing a shaft insertion step after the first cutting step in the method of manufacturing a stacked rotor for an axial induction generator according to the present invention.
Figure 10 is a screen of a thermometer measuring the internal temperature of the axial induction generator after 30 minutes of driving by the test, (a) is by the background art, (b) is an exemplary view showing the one according to the present invention.

Hereinafter, various embodiments of this document will be described with reference to the accompanying drawings. However, this is not intended to limit the technology described in this document to specific embodiments, and is to be understood as including various modifications, equivalents, and/or alternatives of the embodiments of this document. In connection with the description of the drawings, like reference numerals may be used for like elements.

In addition, expressions such as “first,” “second,” etc. used in this document may modify various components regardless of order and/or importance, and to distinguish one component from another. It is used only and does not limit the corresponding components. For example, 'first part' and 'second part' may indicate different parts regardless of order or importance. For example, without departing from the scope of rights described in this document, a first element may be called a second element, and similarly, the second element may also be renamed to the first element.

In addition, terms used in this document are only used to describe a specific embodiment, and may not be intended to limit the scope of other embodiments. Singular expressions may include plural expressions unless the context clearly dictates otherwise. Terms used herein, including technical or scientific terms, may have the same meaning as commonly understood by a person of ordinary skill in the technical field described in this document. Among the terms used in this document, terms defined in a general dictionary may be interpreted as having the same or similar meaning as the meaning in the context of the related art, and unless explicitly defined in this document, an ideal or excessively formal meaning. not be interpreted as In some cases, even terms defined in this document cannot be interpreted to exclude the embodiments of this document.

Hereinafter, looking at the present invention, 'method of manufacturing a stacked rotor for an axial induction generator' for solving the above problems together with the accompanying drawings.

Figure 4 is a flow chart showing a method for manufacturing a stacked rotor for an axial induction generator according to the present invention, Figure 5 is a punching step and a winding step in the manufacturing method for a stacked rotor for an axial induction generator according to the present invention As shown, (a) shows a view from above, and (b) is a process chart showing a view from the side. And Figure 6 is another embodiment of the method of manufacturing a stacked rotor for an axial induction generator according to the present invention, which is a process diagram showing that an insulating material is attached to the lower or upper surface of the iron core in the punching step and winding step. It is a process chart showing a hub insertion step, a welding step, a first cutting step, and a casting step in the method of manufacturing a multilayer rotor for an axial induction generator according to the present invention. And Figure 8 is a process chart showing the casting step and the first cutting step in the method of manufacturing a multilayer rotor for an axial induction generator according to the present invention, Figure 9 is a multilayer rotor for an axial induction generator according to the present invention It is a process chart showing the shaft insertion step after the first cutting step in the manufacturing method.

1. Punching step (S1)

As shown in FIG. 5, a punching step (S1) of punching holes 115 at a pitch defined in the length direction of the strip-shaped iron core 110 is performed. At this time, the iron core 110 uses a silicon steel plate, which is a material for reducing iron loss, and may have a thickness of 0.8 mm to 1.2 mm and a width of 20 mm to 30 mm. When the iron core 110 having the above dimensions is used, it is possible to prevent a phenomenon in which the shape is changed during punching and subsequent winding step (S2). At this time, punching is performed using a conventional punching machine (P). The punching machine P is a general one that is punched by a mold that reciprocates up and down.

As another embodiment, as shown in FIG. 6, in the punching step (S1), an insulating material (I) may be selectively attached to the upper and lower surfaces of the iron core 110. At this time, the thickness and width of the insulating material (I) may be the same as those of the iron core 110 as an example. As such, by using the iron core 110 to which the insulating material I is attached, the iron loss can be reduced because the insulating material I is interposed between the iron cores 110 stacked in the subsequent winding step (S2). In general, since the thickness of the iron core 110 is thin and the iron loss can be reduced as the insulating material (I) is interposed between the iron core 110, it is known to anyone skilled in the art, a detailed description thereof will be omitted.

2. Winding step (S2)

As shown in FIG. 5, a winding step (S2) of winding the iron core 110 discharged through the punching step (S1) in a circular shape is performed. That is, the iron core 110 is wound around the bobbin K rotated by a winding machine (not shown). Accordingly, the iron core 110 has a disk shape with a hub hole H formed in the center, and the iron core 110 is stacked in parallel with respect to the axial direction. In addition, since the adhesive is applied to the lower surface of the iron core 110 at this time, they are attached to each other in a wound state so that they do not come loose. The adhesive may be, for example, a silicone adhesive or the like.

As another embodiment, as shown in FIG. 6, when the insulating material (I) is selectively attached to the upper and lower surfaces of the iron core 110 in the punching step (S1), the insulating material (I) is interposed between the wound iron cores 110. Iron loss can be effectively reduced. At this time, since the adhesive is applied to the lower surface of the insulating material (I), it is attached to each other in a wound state so that it does not unwind. The adhesive may be, for example, a silicone adhesive or the like.

At this time, since the holes 115 are radially overlapped, the slits 117 are formed by the radially overlapped holes 115 in the first cutting step (S4).

3. Welding step (S3)

As shown in FIG. 7, the welding step of welding the iron core 110 that has gone through the winding step (S2) so that it does not unwind, inserting the hub 120 into the hub hole H formed in the center and welding it to the iron core 110 ( S3) is made. Since the welding step (S3) is performed in this way, the wound state can be maintained while the adhesive is solidified. That is, beads (B) are formed on the upper and lower surfaces of the wound iron core 110 to prevent unraveling. In addition, the hub 120 is a metal material in which a shaft hole 125 is formed, and is welded and attached to the iron core 110 along the circumference of the hub 120 .

4. Cutting molding step (S4)

As shown in FIG. 7, one side surface (one of the upper and lower surfaces) of the iron core 110 that has undergone the welding step (S3) is cut with a milling machine or a grinding machine. Accordingly, one side (either upper or lower portion) of the hole 115 is opened, and a slit 117 is formed that is open outward from the center of the iron core 110 and is arranged along the circumferential direction. Next, the core (C) is inserted into the hub 120 of the iron core 110 and put into the mold (M) with the slit 117 facing upward. Next, since the molten aluminum 140 is injected, the aluminum 140 covers one side of the iron core 110 and forms an edge F. After the aluminum 140 has solidified. The iron core 110 is separated from the mold (M).

After that, the same process of cutting and molding is performed on the opposite side of the iron core 110, and then the core C is removed. The core C serves to prevent the hub 120 from being filled with molten aluminum.

As such, the reason why one side of the iron core 110 undergoes the cutting and molding process and then the other side of the iron core 110 undergoes the cutting and molding process is to mold the wound iron core 110 without disassembling it. If both sides of the core 110 are sequentially cut, the bead B disappears and the core 110 is dismantled, so the molding process cannot be performed.

5. Cutting step (S5)

As shown in FIGS. 8 and 9, the upper and lower surfaces of the iron core 110 and the edge F are cut to expose the upper and lower surfaces of the iron core 110 to allow magnetic flux to pass through the cutting molding step (S4) A cutting step (S6) is made. Cutting is performed using a milling machine or a grinding machine to obtain the designed size and shape using a milling cutter, an end mill, or a grinding wheel. At this time, of course, the rim (F) has a shape of a prescribed dimension, and the hub 120 can also be cut.

6. Insertion step (S6)

The process of the present invention is completed by the shaft insertion step (S7) of inserting and fixing the shaft 130 to the hub 120 that has passed through the cutting step (S5).

Next, the multilayer rotor 100 according to the manufacturing method of the multilayer rotor for an axial induction generator according to the present invention is configured through the above manufacturing process, which is another claim of the present invention.

(Test Methods)

The performance of the rotor according to the above-described embodiment of the present invention (without the insulating material (I)) and the background art was tested as follows.

Exam Date: May 6, 2021

Test agency: Daegu Machinery Parts Research Institute - Dynamo test

Test name: Comparative test of characteristics of existing generator, silicon steel laminated rotor core and stator winding number increase core.

Test content: A generator equipped with a rotor according to an embodiment of the present invention is mounted on a motor characteristic test dynamo, rotated at 4,000 rpm, and continuously operated for 1 hour and 30 minutes to output electrical energy. Comparison of input electricity amount at no load, 8kW, 10kW continuous test.

(dynamo tester)

1. Input amount of electricity at no load

background art Example note input power 1.08kW 0.67kW 4,000 rpm/ no load test generator output 0 kW 0 kW 4,000 rpm/no load test

In the embodiment, it can be seen that the mechanical input power at no load is small and the no-load torque applied to the generator input shaft is small due to the lightweight rotor and precision balance.

2. 8kW continuous operation

background art Example note input power 10.243 kW 0.67kW 4,000rpm generator output 8.269kW 8.266kW 4,000rpm efficiency 80.7% 85% 4.3% improvement

3. 10kW continuous operation

background art Example note input power 12.637kW 12.293 kW 4,000rpm generator output 10.169kW 10.183 kW 4,000rpm efficiency 80.5% 82.9% 2.4% improvement

In addition, as a result of checking the temperature inside each induction generator through the above test, the same result as in FIG. 10 could be derived. That is, in (a) of FIG. 10, it can be seen that the temperature rises up to 164.0 ° C. as the temperature of the background art, and in (b) of FIG. 10, as the temperature of the embodiment, the temperature rises up to 92.8 ° C.

According to the present invention reviewed above, magnetic flux is generated in the axial direction due to the characteristics of the axial induction generator. Therefore, in the present invention, since the iron core 110 can be stacked in parallel with the axial direction, iron loss can be reduced more efficiently than a single iron core as in the background art. In particular, as the thickness of the iron core 110 is reduced, the iron loss can be more effectively reduced. Also, as shown in FIG. 6 , iron loss can be further reduced when an insulator is interposed between the iron cores 110 . That is, as can be seen from the above test example, it can be seen that the input to output efficiency is superior to that of the background art. In addition, since heat generated in the iron core 110 can be reduced compared to the background art, efficiency can be further improved.

S1: punching step S2: winding step
S3: welding step S4: first cutting step
S5: casting step S6: cutting step
S7: insertion step
100: Stacked rotor by manufacturing method of stacked rotor for axial induction generator
110: iron core 115: hole
117: slit I: insulating material
P: punching machine B: bead
120: hub 125: shaft hole
C: core 130: shaft
140: aluminum F: frame
M: mold K: bobbin
H: hub hole

Claims (4)

A punching step (S1) of punching holes 115 at a pitch prescribed in the length direction of the strip-shaped iron core 110;
A winding step (S2) of winding the iron core 110 discharged through the punching step (S1) in a circular shape;
A welding step (S3) of welding the iron core 110 that has passed through the winding step (S2) to prevent it from unwinding, inserting a hub 120 into the center and welding it to the iron core 110;
One side (one of the upper and lower surfaces) of the iron core 110 that has passed through the welding step (S3) is cut, and one side (one of the upper and lower parts) of the hole 115 is opened, and the iron core 110 After forming a slit 117 open outward from the center and arranged along the circumferential direction, the core C is inserted into the hub 120 of the iron core 110, and the slit 117 faces upward. After putting it in the mold (M) to do so, molten aluminum (140) is injected so that the aluminum (140) covers one side of the iron core (110) and forms an edge (F), and the process is performed on the iron core (110) A cutting molding step (S4) of removing the core (C) after performing the same on the opposite side of the;
Cutting to expose the upper and lower surfaces of the iron core 110 by cutting the upper and lower surfaces and the rim F of the iron core 110 that has passed through the cutting molding step (S4), and forming the rim F according to the prescribed dimensions. Step (S6),
A method of manufacturing a stacked rotor for an axial induction generator, characterized in that it comprises a shaft insertion step (S7) of inserting and fixing the shaft 130 to the hub 120 that has undergone the cutting step (S6).
According to claim 1,
In the winding step (S2), the method of manufacturing a stacked rotor for an axial induction generator, characterized in that the winding so that the hole 115 radially overlaps.
According to claim 2,
Method of manufacturing a stacked rotor for an axial induction generator, characterized in that the insulating material (I) is selectively attached to the upper and lower surfaces of the iron core 110 injected in the punching step (S1).
Stacked rotors by a manufacturing method of a stacked rotor for an axial induction generator, characterized in that manufactured by the manufacturing method of a stacked rotor for an axial induction generator according to any one of claims 1 to 3 .

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