Stator structure
The stator structure addresses the challenge of reducing magnetic material usage while maintaining strength by incorporating a non-planar annular magnetic path with concave-convex and bent portions, achieving a thin, strong stator without high-strength materials or additional components.
Patent Information
- Application Number
- JP2023197871
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2023-11-22
- Publication Date
- 2025-06-03
AI Technical Summary
Existing stator designs face challenges in reducing the amount of magnetic material used while maintaining strength, as thinning the stator decreases bending strength and resonance points, and adding external components like ribs increases cost.
The stator structure incorporates an annular magnetic path with a non-planar portion that includes concave-convex uneven surfaces and bent portions, which enhances bending strength and resonance points without using high-strength materials or additional components.
This design allows for a thin stator with required strength, suppressing deformation and resonance, thus eliminating the need for high-strength materials and additional reinforcement components.
Smart Images
Figure 2025084186000001_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to a stator structure, and particularly to a stator structure used in a resolver, a magnetostrictive sensor, a motor, or the like.
Background Art
[0002] In a resolver, a magnetostrictive sensor, a motor, or the like, there is a stator in which a stator coil is wound around a protruding magnetic pole portion. In this type of stator, a thin magnetic steel sheet may be used for the purpose of cost reduction and weight reduction by reducing the amount of magnetic material used.
[0003] Simply thinning the stator has problems such as a decrease in bending strength and resonance points. To solve this problem, as a conventional stator design method, (1) Do not make the steel sheet thinner than necessary, (2) Select a high-strength material for the steel sheet, (3) Add external components such as ribs to the stator to ensure bending strength, and such measures are necessary.
[0004] In the above (1), the amount of magnetic material used cannot be reduced. In the above (2), high-strength materials are expensive and it is not realistic to implement. In the above (3), there is a problem that the cost increases due to the addition of external components such as ribs. Therefore, cost reduction by reducing the amount of magnetic material used has been difficult in practice. Note that a structure in which external components such as ribs are added to ensure strength is described in Patent Document 1.
Prior Art Documents
Patent Documents
[0005]
Patent Document 1
Summary of the Invention
Problems to be Solved by the Invention
[0006] In Patent Document 1, the strength of the portion to be reinforced is reinforced by adding ribs in a direction perpendicular to the protruding portion which is the portion to be reinforced. Note that Patent Document 1 discloses integrally forming ribs in a direction perpendicular to a resin-made protruding portion.
[0007] However, the stator is made of a metal plate (steel plate), and there is a problem that the resin component integral forming technology of Patent Document 1 cannot be applied. The present invention has been made to solve the above problems, and an object thereof is to provide a stator which is thin and has a required strength without using a high-strength material and without providing additional components.
Means for Solving the Problems
[0008] The stator structure according to this invention has an annular magnetic path portion and a plurality of protruding magnetic pole portions protruding from the annular magnetic path portion inward at predetermined angular intervals. The annular magnetic path portion includes an annular planar portion and an annular non-planar portion.
[0009] The non-planar portion has an uneven portion where one surface is concave and the other surface is convex, and the uneven portion extends in the annular direction in the annular magnetic path portion.
[0010] In the stator structure according to this invention, the non-planar portion is composed of at least one portion extending in the annular direction.
[0011] In the stator structure according to this invention, when the non-planar portion is composed of at least one portion extending in the annular direction, let x be an odd number of 1 or more, and x discontinuous regions are provided in the non-planar portion, and the non-planar portion is composed of x uneven portions.
[0012] In the stator structure according to this invention, the non-planar portion is formed as a bent portion having a predetermined angle with respect to the planar portion at the outer periphery of the planar portion.
[0013] In the stator structure according to the present invention, the non-planar portion extends in the circumferential direction in the annular magnetic path portion, and includes an uneven portion having one concave surface and the other convex surface, and a bent portion having a predetermined angle with respect to the planar portion on the outer periphery of the planar portion.
Advantages of the Invention
[0014] In the stator structure according to the present invention, since it has an annular magnetic path portion and a plurality of protruding magnetic pole portions protruding inward from the annular magnetic path portion at predetermined angular intervals, and the annular magnetic path portion includes an annular planar portion and an annular non-planar portion, it is possible to provide a thin stator having the required strength without using a high-strength material and without providing additional components.
Brief Description of the Drawings
[0015]
Figure 1
Figure 2
Figure 3
Figure 4
Figure 5
Figure 6
Figure 7
Figure 8
Figure 9
Figure 10
Figure 11
Figure 12
Figure 13
Figure 14
Embodiments for Carrying Out the Invention
[0016] Hereinafter, embodiments of the stator structure of the present invention (hereinafter referred to as "the structure of the stator 100") will be described with reference to the drawings. In each figure, the same parts are denoted by the same reference numerals.
[0017] Embodiment 1. First, the structure of the stator 100 in Embodiment 1 will be described with reference to FIGS. 1 to 8. FIG. 1 is a perspective view showing the structure of the stator 100 according to Embodiment 1. FIG. 2 is a cross-sectional view showing the cross-section taken along line II-II of FIG. 1. FIGS. 3 to 6 are cross-sectional views showing modified examples of the non-planar portion of the stator 100 shown in FIG. 1. FIGS. 7 to 8 are perspective views showing modified examples of the non-planar portion of the stator 100 shown in FIG. 1.
[0018] [Structure of the stator 100 in Embodiment 1] The stator 100 mainly has an annular magnetic path portion 110 and a protruding magnetic pole portion 120. The annular magnetic path portion 110 and the protruding magnetic pole portion 120 are formed of a single electromagnetic steel sheet. The annular magnetic path portion 110 is formed in an annular shape. The protruding magnetic pole portion 120 protrudes a plurality of times at predetermined angular intervals inward from the annular magnetic path portion 110. The annular magnetic path portion 110 is provided with an annular planar portion 110a and an annular non-planar portion 130.
[0019] The flat portion 110a in the annular magnetic circuit portion 110 only needs to have a shape that is generally close to a plane, and various surface treatments such as embossing, anti-slip treatment, and roughness may be applied to the surface. Also, even if there are surface roughness, unevenness, undulations, and processing marks during steel plate manufacturing, etc. on the surface that does not function as the non-planar portion 130, that portion is treated as the flat portion 110a. Further, in the annular magnetic circuit portion 110, a region where the non-planar portion 130 is not formed may be treated as the flat portion 110a. The annular non-planar portion 130 is provided at any position of the annular magnetic circuit portion 110. The non-planar portion 130 is provided with concavo-convex portions 130a where one surface is concave and the other surface is convex. The concavo-convex portions 130a extend in the annular direction in the annular magnetic circuit portion 110. The concavo-convex portions 130a are formed by press working called bead working or string drawing.
[0020] In FIGS. 1 and 2, the concavo-convex portions 130a are formed to have a semi-circular cross-section. Note that the cross-section of the concavo-convex portions 130a can be deformed into shapes other than semi-circular, such as the V-shaped shown in FIG. 3, the trapezoidal shape shown in FIG. 4, the double semi-circular shape shown in FIG. 5, and the double semi-circular shape with different orientations shown in FIG. 6. Also, deformations by further combining FIGS. 2 to 6 are possible.
[0021] In FIG. 1, the non-planar portion 130 is formed as a continuous closed ring. That is, the non-planar portion 130 is composed of one continuous part extending in the annular direction. In contrast, the non-planar portion 130 can be composed of at least one non-continuous part extending in the annular direction. As shown in FIG. 7, by providing the discontinuous region 110b, it is possible to form a "C"-shaped non-planar portion 130. That is, the non-planar portion 130 is composed of one non-continuous part extending in the annular direction. In this case, the discontinuous region 110b can be used for positioning.
[0022] As shown in FIG. 8, by providing the discontinuous regions 110b1, 110b2, and 110b3, the non-planar portion 130 is composed of three non-continuous portions (concavo-convex portions 130a1 to 130a3) extending in the circumferential direction. In this case, the discontinuous regions 110b1, 110b2, and 110b3 can be used for positioning. Note that in order to ensure the bending strength, it is desirable that the discontinuous region 110b does not exist at symmetric positions such as 0° and 180°. That is, it is desirable that the number x of the discontinuous regions 110b1 to 110bx and the concavo-convex portions 130a1 to 130ax be an odd number (1, 3, 5,...) rather than an even number. In other words, when the non-planar portion 130 is discontinuous, it is desirable to set x as an odd number of 1 or more, provide x discontinuous regions 110bx in the non-planar portion 130, and configure the non-planar portion 130 with x concavo-convex portions 130ax.
[0023] [Effects Obtained by Embodiment 1] In the stator 100 according to Embodiment 1, it has an annular magnetic path portion 110 and a plurality of protruding magnetic pole portions 120 protruding from the annular magnetic path portion 110 inward at predetermined angular intervals. The annular magnetic path portion 110 includes an annular planar portion 110a and an annular non-planar portion 130. Here, since the annular non-planar portion 130 exists, the deformation of the entire annular magnetic path portion 110 including the planar portion 110a is suppressed. Thereby, even if the stator 100 is thinned, the bending strength increases. Further, due to the presence of the non-planar portion 130, the area of the planar portion 110a becomes smaller, and since the non-planar portion 130 functions the same as a fixed end, the resonance point rises, so resonance does not occur due to vibration during normal use. For this reason, it is not necessary to use a high-strength material, and it is not necessary to provide additional parts for reinforcement, and it becomes possible to provide a thin stator 100 having the required strength. The non-planar portion 130 can be formed by bead processing or string drawing processing in press working. Therefore, the non-planar portion 130 can be easily produced in the annular magnetic path portion 110 of the stator 100. The non-planar portion 130 is composed of a portion extending in at least one circumferential direction. Here, the non-planar portion 130 can be composed of any one of a single continuous portion extending in the circumferential direction, a non-continuous portion extending in the circumferential direction, and a plurality of non-continuous portions extending in the circumferential direction. In this case, the discontinuous region 110b can be used for positioning. In this case, if x is an odd number of 1 or more, and x discontinuous regions 110bx are provided in the non-planar portion 130 and the non-planar portion 130 is composed of x uneven portions 130ax, it is desirable from the viewpoint of ensuring bending strength that the discontinuous regions 110bx do not exist at symmetric positions such as 0° and 180°.
[0024] Embodiment 2. The structure of the stator 100 in Embodiment 2 will be described with reference to FIGS. 9 to 12. FIG. 9 is a perspective view showing the structure of the stator 100 according to Embodiment 2. FIG. 10 is a cross-sectional view showing a cross-section taken along line X-X of FIG. 9. FIGS. 11 to 12 are cross-sectional views showing cross-sections of modified examples of the non-planar portion 130 of the stator 100 shown in FIG. 9. In FIGS. 9 to 12, the same components as those described in Embodiment 1 are denoted by the same reference numerals, and redundant descriptions are omitted, and the description will be centered on the different portions.
[0025] [Structure of the stator 100 in Embodiment 2] The stator 100 mainly has an annular magnetic path portion 110 and a protruding magnetic pole portion 120. The annular magnetic path portion 110 is formed in an annular shape. The protruding magnetic pole portion 120 protrudes a plurality of times at predetermined angular intervals inward from the annular magnetic path portion 110. The annular magnetic path portion 110 is provided with an annular planar portion 110a and an annular non-planar portion 130.
[0026] The non-planar portion 130 is formed as a bent portion 130c having a predetermined angle with respect to the planar portion 110a on the outer periphery of the annular planar portion 110a. In FIGS. 9 and 10, the bending angle of the bent portion 130c is about 90°. For this reason, the bent portion 130c is formed in a wall shape or a cylindrical shape with respect to the planar portion 110a.
[0027] In FIG. 11, the bending angle of the bent portion 130c is approximately 70° which is less than 90°. Therefore, the bent portion 130c is formed in a mortar shape where the opening at the end is the widest and the opening becomes narrower toward the flat portion 110a. The 70° shown here is an example, and any angle exceeding 0° and less than 90° can be selected.
[0028] In FIG. 12, the bending angle of the bent portion 130c is approximately 110° which exceeds 90°. Therefore, the bent portion 130c is formed in a shape near the bottom of a cone where the opening becomes narrower as it moves away from the flat portion 110a. The 110° shown here is an example, and any angle exceeding 90° and less than 180° can be selected.
[0029] [Effects Obtained by Embodiment 2] In the stator 100 according to Embodiment 2, it has an annular magnetic path portion 110 and a plurality of protruding magnetic pole portions 120 that protrude from the annular magnetic path portion 110 inward at predetermined angular intervals. The annular magnetic path portion 110 includes an annular flat portion 110a and an annular non-flat portion 130. The non-flat portion 130 is formed as a bent portion 130c having a predetermined angle with respect to the flat portion 110a on the outer periphery of the annular magnetic path portion 110. Here, since the bent portion 130c exists as the annular non-flat portion 130, deformation of the entire annular magnetic path portion 110 including the flat portion 110a is suppressed. As a result, even when the stator 100 is thinned, the bending strength increases. Also, due to the presence of the bent portion 130c, the outer periphery of the annular magnetic path portion 110 becomes a fixed end and does not vibrate. Therefore, the resonance point rises and resonance does not occur due to vibration during normal use. For this reason, it is not necessary to use a high-strength material, and it is not necessary to provide additional parts for reinforcement, and it becomes possible to provide a stator 100 that is thin and has the required strength.
[0030] Embodiment 3. The structure of the stator 100 in Embodiment 3 will be described with reference to FIGS. 13 and 14. FIGS. 13 and 14 are cross-sectional views showing the cross-section of the structure of the stator 100 according to Embodiment 3. In FIGS. 13 and 14, the same components as those described in Embodiment 1 and Embodiment 2 are denoted by the same reference numerals, and redundant descriptions are omitted, and the description will be centered on the different parts.
[0031] [Structure of the Stator 100 in Embodiment 3] In the stator 100 shown in FIG. 13, the non-planar portion 130 is provided with an uneven portion 130a in which one surface is concave and the other surface is convex, similar to FIG. 2. The uneven portion 130a is formed so as to extend in the circumferential direction in the annular magnetic path portion 110. Note that the uneven portion 130a can be deformed as shown in FIGS. 3 to 8. The non-planar portion 130 is further formed with a bent portion 130c having a predetermined angle with respect to the planar portion 110a on the outer periphery of the annular planar portion 110a. Note that the bent portion 130c can be deformed as shown in FIGS. 11 and 12.
[0032] In the stator 100 shown in FIG. 13, the convex direction of the uneven portion 130a and the bending direction of the bent portion 130c face in opposite directions. On the other hand, in the stator 100 shown in FIG. 14, the convex direction of the uneven portion 130a and the bending direction of the bent portion 130c face in the same direction. Note that also in the stator 100 shown in FIG. 14, the uneven portion 130a can be deformed as shown in FIGS. 3 to 8. And also in the stator 100 shown in FIG. 14, the bent portion 130c can be deformed as shown in FIGS. 11 and 12.
[0033] [Effects Obtained by Embodiment 3] In the stator 100 according to Embodiment 3, as the annular non-planar portion 130, an annular planar portion 110a, and concavo-convex portions 130a and bent portions 130c are provided. Here, since the concavo-convex portions 130a and the bent portions 130c exist as the annular non-planar portion 130, deformation of the entire annular magnetic path portion 110 including the planar portion 110a is suppressed. In this case, since there are two types of non-planar portions 130, namely the concavo-convex portions 130a and the bent portions 130c, deformation of the entire annular magnetic path portion 110 is extremely effectively suppressed. As a result, even if the stator 100 is thinned, the bending strength increases. Further, the concavo-convex portions 130a and the bent portions 130c increase the bending strength and make it difficult to vibrate, so the resonance point rises and resonance does not occur due to vibration during normal use. Therefore, it is not necessary to use a high-strength material, and it is not necessary to provide additional components for reinforcement, and it is possible to provide a thin stator 100 having the required strength.
Description of reference numerals
[0034] 100 Stator, 110 Annular magnetic path portion, 110a Planar portion, 110b, 110b1~110bx Discontinuous region, 120 Protruding magnetic pole portion, 130 Non-planar portion, 130a, 130a1~130ax Concavo-convex portion, 130c Bent portion.
Claims
1. A stator structure having an annular magnetic circuit portion (110) and a plurality of protruding magnetic pole portions (120) protruding inward from the annular magnetic circuit portion (110) at predetermined angular intervals. The annular magnetic circuit portion (110) includes an annular planar portion (110a) and an annular non-planar portion (130). Stator structure.
2. The non-planar portion (130) has a concavo-convex portion (130a) with one surface being concave and the other surface being convex, and the concavo-convex portion (130a) extends in the annular direction in the annular magnetic circuit portion (110). The stator structure according to Claim 1.
3. The non-planar portion (130) is composed of at least one portion extending in the annular direction. The stator structure according to Claim 1.
4. When x is an odd number of 1 or more, x discontinuous regions (110bx) are provided in the non-planar portion (130), The non-planar portion (130) is composed of x concavo-convex portions (130ax). The stator structure according to Claim 3.
5. The non-planar portion (130) is formed as a bent portion (130c) having a predetermined angle with respect to the planar portion (110a) at the outer periphery of the planar portion (110a). The stator structure according to Claim 1.
6. The non-planar portion (130) includes a concavo-convex portion (130a) that extends in the annular direction in the annular magnetic circuit portion (110) and has one surface being concave and the other surface being convex, and a bent portion (130c) having a predetermined angle with respect to the planar portion (110a) at the outer periphery of the planar portion (110a). Including The stator structure according to Claim 1.
Citation Information
Patent Citations
Sensor assembly
JP2008076066A