Hairpin and method for manufacturing and assembling hairpin

Abstract

The present invention relates to a hairpin wound around a stator and, more specifically, to a hairpin with improved ease of manufacture and assembly. In the hairpin and a method for manufacturing and assembling the hairpin according to the present invention, the hairpin includes at least two bending parts, and thus, when applied to an induction motor having a low number of poles, prevents the end height of a coil assembly comprising the hairpin from becoming excessively high, reduces manufacturing costs, and can ensure motor performance. Moreover, when a plurality of the hairpins are inserted into the stator, a portion of the overlapping parts of the hairpins is bent toward the outside of the center of the stator, thereby having the effect of making it easy for the plurality of hairpins to be inserted overlapped.

Description

Hairpins and methods for making and assembling hairpins

[0001] The present invention relates to a hairpin wound on a stator, and more particularly, to a hairpin having improved ease of manufacture and assembly.

[0002] Conventional industrial induction motors have employed annular stator windings. While this approach offered ease of manufacture and cost savings, its low space factor of 40-45% limited its ability to significantly improve motor performance. In contrast, hairpin windings offer a high space factor of over 60%, offering significantly superior performance compared to annular windings. Consequently, they have been primarily used in high-performance applications such as aviation and automotive.

[0003] However, hairpin windings have primarily been used in high-performance motors due to the complex manufacturing process that requires individual strands and the difficulty in obtaining standardized windings. This has limited their application to general industrial induction motors. However, with the recent increase in demand for high-performance motors, the cost of hairpin winding production has decreased, leading to an increase in their use in industrial induction motors.

[0004] However, the existing hairpin winding technology was mainly used in multi-pole motors, such as automotive motors with 8 or more poles. When applied to induction motors with a low number of poles (e.g., 4 or 6 poles), the coil end part expanded, resulting in an excessively high coil end height, significantly reducing efficiency in terms of space utilization. This also led to increased manufacturing costs and deterioration in motor performance.

[0005] [Prior Art Literature]

[0006] [Patent Document]

[0007] (Patent Document 1) Republic of Korea Publication No. 10-2014-0083730 "Phase Arrangement Structure of Hairpin Winding Motor"

[0008] The present invention has been devised to solve the above problems, and the purpose of the present invention is to provide a hairpin and a method for manufacturing and assembling the hairpin, which can prevent the end height of a coil assembly made of a hairpin from becoming excessively high when applied to an induction motor having a low number of poles by including two or more banding portions in the hairpin, reduce the manufacturing cost, and secure the motor performance.

[0009] In addition, a method for manufacturing and assembling a hairpin is provided, which enables multiple hairpins to be easily inserted in an overlapping manner by banding a portion of the overlapping portion between hairpins toward the outside of the center of the stator as multiple hairpins are inserted into the stator.

[0010] In order to solve the above-described problem, a hairpin according to one embodiment of the present invention is a hairpin which is a coil strand that is inserted into a stator and wound, the hairpin including two insertion portions provided at both ends of the hairpin, inserted into a shoe of the stator, and extending in the axial direction of the stator, and a connection portion including two or more first bending portions that connect the two insertion portions and are bent at a predetermined angle, and the insertion portion and the connection portion are formed integrally to form a hairpin which is a single coil strand.

[0011] In addition, the hairpin is characterized in that it includes a second banding portion positioned at a connecting portion of the insertion portion and the connecting portion and banded at a predetermined angle.

[0012] Additionally, the second banding portion is characterized in that one of the insert portions is positioned on the outer side of the stator in the circumferential direction compared to the connecting portion.

[0013] In addition, the first banding portion and the second banding portion are formed in a semicircular shape with one side and the other side being flat, and the insertion portion and the connecting portion are connected to the corners without curvature.

[0014] Additionally, the bending angle in the first banding section is characterized by being greater than the bending angle in the second banding section.

[0015] Additionally, the bending angles in each first banding section are characterized by being the same.

[0016] Additionally, it is characterized in that at least two of the bending angles in each first banding section are different from each other.

[0017] Additionally, the connecting portion is characterized by including two first extension portions, one end of which is connected to one of the insert portions and the other end of which is connected to one of the first banding portions, and one or more second extension portions, both ends of which are connected to the first banding portion.

[0018] Additionally, the extension length of the second extension is characterized by being longer than the extension length of each of the first extensions.

[0019] Additionally, the extension lengths of each first extension are characterized by being equal to each other.

[0020] Additionally, it is characterized in that the extension lengths of each first extension are different from each other.

[0021] In addition, it is characterized by including (a) a step of injecting an insertion portion and a connection portion of a hairpin, (b) a step of forming a first banding portion and a second banding portion by banding the insertion portion and the connection portion of the hairpin, and (c) a step of inserting the hairpin into a stator and assembling it.

[0022] In addition, step (b) is characterized by including a step of forming two or more first banding parts by banding a connecting part (b1), and a step of forming a second banding part by banding a connecting part of an insertion part and a connecting part (b2).

[0023] The hairpin of the present invention and the method for manufacturing and assembling the hairpin by the above configuration have the effect of preventing the end height of the coil assembly made of the hairpin from becoming excessively high, reducing the manufacturing cost, and securing the motor performance when applied to an induction motor having a low number of poles by including two or more banding portions in the hairpin.

[0024] In addition, as multiple hairpins are inserted into the stator, there is an effect of making it easy for multiple hairpins to be inserted while overlapping by banding a portion of the overlapping portion between the hairpins toward the outside of the center of the stator.

[0025] Fig. 1 is a plan view showing a stator in which a hairpin of the present invention is wound.

[0026] Figure 2 is a perspective view showing the entire hairpin of the present invention.

[0027] Fig. 3 is a partial perspective view showing a stator in which a hairpin of the present invention is wound.

[0028] Figure 4 is a partial perspective view showing the second banding portion of the present invention.

[0029] Figures 5 and 6 are schematic diagrams showing the hairpin of the present invention.

[0030] Figure 7 is a flowchart illustrating a method for manufacturing and assembling a hairpin of the present invention.

[0031] Figure 8 is a flowchart illustrating detailed steps of the banding step in the method for manufacturing and assembling a hairpin of the present invention.

[0032] Hereinafter, the technical concept of the present invention will be described in more detail using the attached drawings. Prior to this, it should be noted that the terms and words used in this specification and claims should not be construed as limited to their conventional or dictionary meanings. Based on the principle that the inventor can appropriately define the concept of a term to best explain his or her invention, they should be interpreted in a way that aligns with the technical concept of the present invention.

[0033] Hereinafter, the basic configuration of the present invention will be described with reference to FIGS. 1 and 2.

[0034] As illustrated in FIG. 1, the hairpin (1000) of the present invention may be a coil strand made of copper that is wound around a stator (S) of an induction motor. At this time, as illustrated in FIG. 2, the hairpin (1000) may be composed of two regions: an insertion portion (100) and a connection portion (200). More specifically, the insertion portion (100) is provided at both ends of the hairpin (1000), is fitted into a shoe of the stator (S), and may extend in the axial direction of the stator (S). Two insertion portions (1000) may be provided, one at each end of the hairpin (1000). In addition, the connection portion (200) may connect two insertion portions (100) and may include two or more first bending portions (210) that are bent at a predetermined angle. As described above, it is preferable that the insertion portion (100) and the connection portion (200) be formed integrally to form a hairpin (1000) which is a single coil strand.

[0035] In this way, since the connecting portion (200) includes two or more first bending portions (210), when applied to a low-pole motor, that is, when the coil pitch angle is wide and the extension length of the connecting portion (200) is lengthened accordingly, the axial height of the connecting portion (200) can be prevented from becoming excessively high. Accordingly, space utilization can be increased and efficiency reduction due to increased copper loss can be minimized. In addition, in the case of the conventional hairpin (1000), since there was a limit to the bending angle at which it could be bent, when applied to a low-pole motor, the axial height of the end portion of the hairpin (1000) could become excessively high. However, in the case of the present invention, this can be solved by including two or more first bending portions (210).

[0036] Additionally, the hairpin (1000) may include a second banding portion (110) positioned on the connecting portion (200) of the insertion portion (100) and the connecting portion (200) and bent at a predetermined angle. By including the second banding portion (110), the insertion portion (100) and the connecting portion (200) can be distinguished.

[0037] Hereinafter, the second banding portion (110) of the present invention will be described in more detail with reference to FIGS. 3 and 4.

[0038] As illustrated in FIG. 3, the hairpin (1000) can be bent such that one of the second bending portions (110) is positioned on the outer side of the stator (S) in the circumferential direction compared to the connecting portion (200) of the insertion portion (100). Accordingly, even if a plurality of hairpins (1000) are wound around the stator (S) and a certain portion overlaps with each other, a position for winding each hairpin (1000) can be secured.

[0039] In addition, as illustrated in FIG. 4, the first bending portion (210) and the second bending portion (110) may be formed in a semicircular shape with one side and the other side flat, and the insertion portion (100) and the connection portion (200) may be formed to be connected to corners without curvature. That is, the second bending portion (110) may not be simply bent, but may be bent while twisting one or more times. Accordingly, one of the insertion portions (100) in the second bending portion (110) may be easily bent so that it is positioned on the outer side of the circumference of the stator (S) compared to the connection portion (200).

[0040] Hereinafter, the numerical limitations of the hairpin (1000) of the present invention will be described in more detail with reference to FIGS. 5 and 6.

[0041] As shown in Fig. 5, the bending angle in the first banding section (210) is , And, the bending angle in the second banding section (110) When this is said, the bending angle in the first banding section (210) , is the banding angle in the second banding section (110) It can be larger. Accordingly, the shape of the connecting portion (200) in which the first banding portion (210) is formed can take on a gentle shape, and accordingly, even if the number of poles of the stator (S) is low and the coil pitch angle is widened, the axial protrusion height of the coil end portion can be reduced so as not to become excessively high.

[0042] At this time, the bending angles in each of the first bending portions (210) may be the same. Accordingly, the hairpin (1000) may be formed symmetrically with respect to the extension direction center of the connecting portion (200), and winding to the stator (S) may be facilitated. Alternatively, at least any two of the bending angles in each of the first bending portions (210) may be different from each other. Accordingly, it may be easily applied when the stator (S) has a special shape, or when the hairpin (1000) is to be wound in a specific shape.

[0043] In addition, as illustrated in FIG. 6, the connecting portion (200) may include two first extension portions (220) having one end connected to one of the insert portions (100) and the other end connected to one of the first banding portions (210), and one or more second extension portions (230) having both ends connected to the first banding portion (210), wherein the extension length of each of the first extension portions (220) is , And, the extension length of the second extension (230) When this is said, the extension length of the second extension (230) is the extension length of each first extension (220) , It can be longer. Accordingly, even if the number of poles of the stator (S) is reduced and the coil pitch angle is widened, the axial protrusion height of the coil end can be reduced so that it does not become excessively high.

[0044] At this time, it is preferable that the extension lengths of each of the first extension portions (220) are the same. Accordingly, the hairpin (1000) can be formed symmetrically with respect to the extension direction center of the connecting portion (200), and winding to the stator (S) can be facilitated. Alternatively, it is preferable that the extension lengths of each of the first extension portions (220) are different from each other. Accordingly, it can be easily applied even when the stator (S) has a special shape, or when the hairpin (1000) is to be wound in a specific shape.

[0045] Hereinafter, the manufacturing and assembly method of the hairpin (1000) of the present invention will be described in more detail with reference to FIGS. 7 and 8.

[0046] As illustrated in FIG. 7, the method for manufacturing and assembling a hairpin (1000) may include (a) a step of injecting an insertion portion (100) and a connection portion (200) of the hairpin (1000), (b) a step of forming a first banding portion (210) and a second banding portion (110) by bending the insertion portion (100) and the connection portion (200) of the hairpin (1000), and (c) a step of inserting and assembling the hairpin (1000) into a stator (S). In addition, as illustrated in FIG. 8, step (b) may include a step of (b1) forming two or more first banding portions (210) by banding the connecting portion (200), and a step of (b2) forming a second banding portion (110) by banding the connecting portion (200) of the insertion portion (100) and the connecting portion (200). At this time, steps (a), (b), and (c) may be performed in any order regardless of the order of description or may be performed simultaneously depending on the application. Steps (b1) and (b2) may also be performed in any order regardless of the order of description or may be performed simultaneously depending on the application.

[0047] At this time, the bending angle in the first banding portion (210) formed in step (b1) is , And, the bending angle in the second banding part (110) formed in step (b2) When this is said, the bending angle in the first banding section (210) , is the banding angle in the second banding section (110) It can be larger. Accordingly, the shape of the connecting portion (200) in which the first banding portion (210) is formed can take on a gentle shape, and accordingly, even if the number of poles of the stator (S) is low and the coil pitch angle is widened, the axial protrusion height of the coil end portion can be reduced so as not to become excessively high.

[0048] At this time, the bending angles in each of the first bending portions (210) may be the same. Accordingly, the hairpin (1000) may be formed symmetrically with respect to the extension direction center of the connecting portion (200), and winding to the stator (S) may be facilitated. Alternatively, at least any two of the bending angles in each of the first bending portions (210) may be different from each other. Accordingly, it may be easily applied when the stator (S) has a special shape, or when the hairpin (1000) is to be wound in a specific shape.

[0049] In addition, the second bending portion (110) formed in step (b2) can be bent so that one of the insertion portions (100) is positioned on the outer side of the stator (S) in the circumferential direction compared to the connection portion (200). Accordingly, even if a plurality of hairpins (1000) are wound around the stator (S) and a certain portion overlaps with each other, a position for winding each hairpin (1000) can be secured. In addition, the first bending portion (210) and the second bending portion (110) can be formed in a semicircular shape with one side and the other side flat, and the insertion portion (100) and the connection portion (200) can be formed so that they are connected at corners without curvature. That is, the second bending portion (110) can be bent by twisting one or more times rather than simply bending. Accordingly, one of the insertion portions (100) in the second banding portion (110) can be easily banded so that it is positioned on the outer side of the stator (S) in the circumferential direction compared to the connecting portion (200).

[0050] The technical concept of the present invention should not be construed solely based on the above-described embodiments. The scope of application is diverse, and various modifications and variations are possible within the scope of those skilled in the art without departing from the spirit of the invention as claimed in the claims. Therefore, such improvements and modifications, as long as they are obvious to those skilled in the art, fall within the scope of protection of the present invention.

[0051] The technical concept of the present invention should not be construed solely based on the above-described embodiments. The scope of application is diverse, and various modifications and variations are possible within the scope of those skilled in the art without departing from the spirit of the invention as claimed in the claims. Therefore, such improvements and modifications, as long as they are obvious to those skilled in the art, fall within the scope of protection of the present invention.

[0052] [Explanation of symbols]

[0053] 1000: Hairpin

[0054] 100: Insertion part

[0055] 110: Second banding section

[0056] 200: Connection

[0057] 210: First banding section

[0058] 220: 1st extension

[0059] 230: Second Extension

[0060] S: Stator

Claims

1. In a hairpin, which is a coil strand that is wound by being inserted into a stator, Two inserts provided at both ends of the hairpin, fitted into the shoes of the stator, and extending in the axial direction of the stator; A connecting portion including two or more first banding portions that connect the two above-mentioned insert portions and are bent at a predetermined angle; A hairpin characterized in that the insertion portion and the connection portion are formed integrally to form the hairpin as a single coil strand.

2. In paragraph 1, The above hairpin is, A hairpin characterized by including a second banding portion positioned at a connecting portion of the insertion portion and the connecting portion and banded at a predetermined angle.

3. In paragraph 2, A hairpin characterized in that the second banding portion is banded so that one of the insert portions is positioned on the outer side of the stator in the circumferential direction compared to the connecting portion.

4. In paragraph 2, The first banding portion and the second banding portion are, A hairpin characterized in that one side and the other side are formed in a flat semicircle shape, and the insertion part and the connecting part are connected to a corner without a curve.

5. In paragraph 2, The bending angle in the first banding section is A hairpin characterized in that the banding angle in the second banding section is greater than the banding angle.

6. In paragraph 1, A hairpin characterized in that the bending angles in each of the first banding portions are the same.

7. In paragraph 1, A hairpin characterized in that at least two of the bending angles in each of the first banding portions are different from each other.

8. In paragraph 1, The above connection part, Two first extension parts, one end of which is connected to one of the above insertion parts and the other end of which is connected to one of the first banding parts, A hairpin characterized in that both ends include at least one second extension portion connected to the first banding portion.

9. In paragraph 8, The extension length of the above second extension is, A hairpin characterized in that the extension length is longer than that of each of the first extension portions.

10. In paragraph 8, A hairpin characterized in that the extension lengths of each of the first extension portions are equal to each other.

11. In paragraph 8, A hairpin characterized in that the extension lengths of each of the first extension portions are different from each other.

12. In the method for manufacturing and assembling a hairpin, manufacturing and assembling the hairpin of the first paragraph, (a) a step of injecting the insertion portion and the connecting portion of the hairpin; (b) a step of forming the first banding portion and the second banding portion by banding the insertion portion and the connection portion of the hairpin; (c) A method for manufacturing and assembling a hairpin, characterized in that it comprises a step of inserting the hairpin into the stator and assembling it.

13. In paragraph 12, Step (b) above, (b1) a step of forming two or more of the first banding parts by banding the above connecting part, (b2) A method for manufacturing and assembling a hairpin, characterized in that it includes a step of forming a second banding portion by banding the connecting portion of the insertion portion and the connecting portion.

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