JP5239074B2 - Stator structure, motor and disk type recording apparatus - Google Patents

Description

  The present invention relates to a stator structure, a motor, and a disk type recording apparatus.

  Conventionally, three adjacent teeth are arranged in the circumferential direction of three sets at intervals of 120 °, and among each pair of teeth, the tooth tip width of the center tooth is configured to be larger than the tooth tip width of adjacent teeth on both sides. A stator structure is known that increases the amount of magnetic flux formed in a central tooth to improve torque (see, for example, Patent Document 1).

JP 2004-304928 A

  However, in the stator structure of Patent Document 1, the magnetic flux formed in the central tooth branches to two adjacent teeth (hereinafter referred to as outer teeth) on both sides via the core back. Furthermore, since magnetic flux from other teeth adjacent to the outer side in the circumferential direction also flows, there is a disadvantage that the magnetic flux density in the outer teeth increases and magnetic saturation occurs. When magnetic saturation occurs in the outer teeth, the magnetic flux formed in the central teeth is less likely to flow into the outer teeth, so the amount of magnetic flux generated in the central teeth is limited, and torque improvement is suppressed. There is an inconvenience.

  SUMMARY OF THE INVENTION The present invention has been made in view of the above-described circumstances, and it is possible to prevent the inconvenience that the amount of magnetic flux formed in the teeth is suppressed and to improve the generated torque, the motor and the disk. An object of the present invention is to provide a mold recording apparatus.

In order to achieve the above object, the present invention provides the following means.
The present invention comprises a plurality of teeth portions adjacent in the circumferential direction, and a core back portion that connects these teeth portions in the circumferential direction, and a plurality of segments arranged in the circumferential direction and a space between adjacent segments in the circumferential direction. A stator core having an inter-segment core back to be connected, and a coil wound around a tooth portion of the stator core, the segment including three teeth portions adjacent in the circumferential direction, and in each of the segments, The tooth tip width of the center tooth part is configured to be larger than the tooth tip widths of the tooth parts on both sides thereof, and the inter-segment core back has a smaller cross-sectional area than the core back part, and between the adjacent segments. Provided is a stator structure that suppresses inflow of magnetic flux and prevents magnetic flux saturation from occurring at the tooth portions on both sides .

According to the present invention, when a large amount of magnetic flux is formed in one tooth portion among the plurality of tooth portions constituting the segment, the magnetic flux branches and flows to the tooth portions on both sides via the core back portion. A magnetic circuit is formed.
In this case, since the cross-sectional area of the inter-segment core back that connects the segments in the circumferential direction is smaller than the cross-sectional area of the core back portion in the segment, the magnetic flux flowing over the segment is limited, and the segment It is possible to prevent magnetic flux saturation from occurring at the teeth portions on both sides of the inside.

In the above invention, it provided with three teeth, wherein the segments are circumferentially adjacent, in each segment, the tooth tip width of the central tooth portion has been configured larger than the tooth tip width of the teeth of both sides.
By doing in this way, when the magnetic pole of the permanent magnet of a rotor opposes the tooth tip of a center tooth part, the amount of magnetic flux which enters into a center tooth part from a permanent magnet can be increased, and torque is improved. Can do.
Moreover, in the said invention, the said core back part is integrally formed by the same steel plate as the teeth part of the both sides, and the said inter-segment core back is integrated by the other steel plate same as the said center teeth. The stator core is formed of the core back portion and the inter-segment core back, so that the bending direction of the tip of the central teeth portion is opposite to the bending direction of the tips of the teeth portions on both sides, It is good also as overlapping and forming in the thickness direction.
Moreover, in the said invention, the said core back part is formed by the laminated steel plate which laminated | stacked the steel plate, and the said core back part is formed by the at least 1 steel plate of the said laminated steel plate, The said core back part It is good also as having a smaller cross-sectional area.

In the said invention, it is good also as the segment which adjoins the circumferential direction comprises a mutually different phase.
By doing in this way, an adjacent segment can comprise a separate phase independently, and the flow of the magnetic flux beyond a segment can be made unnecessary.

Moreover, in the said invention, it is good also as the thickness dimension of the said inter-segment core back being smaller than the thickness dimension of the said core back part.
By doing in this way, if the width dimension of the inter-segment core back and the core back part is made equal, the cross-sectional area of the inter-segment core back can be made smaller than the cross-sectional area of the core back part. In this case, the thickness of the steel plate constituting the inter-segment core back may be formed thinner than the thickness of the steel plate constituting the core back portion, and the number of laminated steel plates constituting the inter-segment core back may be determined from the core back portion. It may be less.

In the above invention, the width dimension of the inter-segment core back may be smaller than the width dimension of the core back portion.
By doing in this way, if the thickness dimensions of the inter-segment core back and the core back portion are made equal, the cross-sectional area of the inter-segment core back can be made smaller than the cross-sectional area of the core back portion.

Further, the present invention provides a ring having a stator having any one of the above-described stator structures, and facing the tip of the teeth portion of the stator with a small gap in the radial direction and alternately arranging different magnetic poles in the circumferential direction. And a rotor including a permanent magnet configured as described above.
According to the present invention, by increasing the magnetic flux generated in the central tooth portion of the stator segment, a sufficient magnetic attraction force or magnetic repulsion force for the permanent magnet can be generated to rotate the rotor with a high torque. it can. Thereby, generation | occurrence | production of cogging and an increase in iron loss can be prevented.

The present invention also provides a disk-type recording apparatus comprising a disk-shaped recording medium and the motor that rotationally drives the recording medium.
According to the present invention, the disk-shaped recording medium can be stably rotated by the thin motor, and the apparatus can be thinned and the reliability can be improved.

  ADVANTAGE OF THE INVENTION According to this invention, there exists an effect that generation | occurrence | production of the problem which the amount of magnetic flux formed in teeth is suppressed can be prevented, and generated torque can be improved.

A stator structure, a motor, and a disk-type storage device according to a first embodiment of the present invention will be described below with reference to FIGS.
As shown in FIG. 1, the stator structure 1 according to the present embodiment includes a stator core 3 including a plurality of teeth portions 2 and a coil 4 wound around the teeth portions 2 of the stator core 3.

The stator core 3 includes a plurality of, for example, six segments 5 arranged at intervals in the circumferential direction, and an inter-segment core back 6 that connects the adjacent segments 5.
Each segment 5 includes a segment member 8 formed by connecting the radially outer ends of three teeth portions 2 adjacent in the circumferential direction by an arc-shaped connecting portion 7, and the plate thickness of the annular core back member 9. It is composed of parts that overlap in the direction. On the other hand, the inter-segment core back 6 is constituted by a core back member 9 in a portion where the segment members 8 are not overlapped.
Thereby, the stator core 3 is formed in the annular | circular shape which has the 18 teeth parts 2 which protrude in the radial direction inward as a whole.

  As shown in FIG. 2, the distal end portion 2 a disposed radially inward of each tooth portion 2 is bent into an L shape. Thereby, when each tooth part 2 is configured as a motor 10 as shown in FIG. 3, the tooth part 2 has a large area with respect to the ring-shaped permanent magnets 13 arranged with a minute gap inward in the radial direction. It is designed to face each other.

Of the three tooth portions 2 constituting the segment member 8, the central tooth portion 2 is formed with a larger tooth tip width than the tooth portions 2 on both sides thereof.
The segment member 8 is formed by integrally stacking the punched electromagnetic steel plates, so that the three tooth portions 2 and the arc-shaped connecting portion 7 are integrally formed. The connecting portion 7 of the segment member 8 and the core back member 9 have the same radial width dimension.

In each segment 5, the core back portion 20 of the segment 5 is configured by overlapping the connecting portion 7 of the segment member 8 and the core back member 9 in the thickness direction.
Therefore, the core back part 20 and the inter-segment core back 6 in each segment 5 are different from each other only in the number of layers, that is, the thickness dimension. Has a large cross-sectional area.

As shown in FIG. 3, the motor 10 according to the present embodiment includes a stator 11 having the stator structure 1 and a rotor 12 disposed radially inward of the stator 11.
As described above, the rotor 12 includes a ring-shaped permanent magnet 13 that is opposed to the front end of each tooth portion 2 of the stator 11 in the radial direction with a minute gap, and a shaft 14 that has the permanent magnet 13 disposed on the outer periphery. It has. The permanent magnet 13 has different magnetic poles arranged alternately in the circumferential direction. For example, the number of magnetic poles is 16.

  As shown in FIG. 4, the disk-type recording apparatus 15 according to the present embodiment is oscillated close to the surface of the disk-shaped magnetic recording medium 16 and the magnetic recording medium 16, so that the magnetic recording medium 16 On the other hand, a magnetic head 17 for writing and / or reading magnetic information and the motor 10 for fixing the magnetic recording medium 16 to the shaft 14 and rotating it around the central axis C are provided.

  According to the stator structure 1 according to the present embodiment configured as described above, the tooth tip width of the center tooth portion 2 of the segment 5 is formed larger than the tooth tip widths of the tooth portions 2 on both sides. As shown by arrow A, when the N magnetic pole of the permanent magnet 13 of the rotor 12 is directly opposed to the tooth tip of the central tooth portion 2, an electric current is passed through the coil 4 of the segment 5 as shown in FIG. Magnetic flux is formed in

  That is, the magnetic flux formed in the tooth portion 2 at the center of the segment 5 branches toward the tooth portions 2 on both sides on the tooth tip side and the core back portion 20 side. Accordingly, the magnetic flux of the central tooth portion 2 is formed almost twice as much as the magnetic flux of the tooth portions 2 on both sides. Since the central tooth portion 2 is formed wider than the tooth portions 2 on both sides, the magnetic flux is not saturated in the central tooth portion 2 even if double magnetic flux is formed.

  Further, since the cross-sectional area of the inter-segment core back 6 connecting the adjacent segments 5 is reduced as compared with the core back portion 20 in the segment 5, the flow of magnetic flux from the adjacent segments 5 is suppressed. . Therefore, saturation of the magnetic flux in the tooth portions 2 on both sides of each segment 5 does not occur.

  As a result, a large amount of magnetic flux is formed in the central tooth portion 2 of the segment 5, and the magnetic flux smoothly flows to the tooth portions 2 on both sides, so that the formation of magnetic flux in the central tooth portion 2 is not hindered. Many magnetic fluxes can be formed in the central tooth portion 2.

  Moreover, according to the motor 10 according to the present embodiment including the stator 11 having the stator structure 1 according to the present embodiment, the permanent magnet 13 disposed with a minute gap on the tooth tip side of the central tooth portion 2. In the meantime, a large magnetic repulsive force and / or magnetic attractive force can be generated, and the rotor 12 can be rotated with high torque. Accordingly, there is an advantage that the rotor 12 can be stably rotated with a high torque while reducing the thickness.

  Further, according to the disk type recording apparatus 15 using the motor 10, the disk-shaped magnetic storage medium 16 can be stably rotated while improving the reliability of information writing and reading while achieving a reduction in thickness. There is an advantage that you can.

  In the present embodiment, the stator core 3 is formed by overlapping the segment member 8 obtained by integrally punching the three adjacent tooth portions 2 and the arc-shaped connecting portion 7 and the annular core back member 9. Although configured, the present invention is not limited to this.

  For example, as shown in FIGS. 6 and 7, the central tooth portion 2A of each segment 5 is formed integrally with an annular core back member 9, and the tooth portions 2B on both sides adjacent to the central tooth portion 2A. Alternatively, the segment member 8 ′ obtained by integrally punching the arc-shaped connecting portion 7 may be overlapped in the thickness direction. In this case, as shown in FIG. 6, an increase in the thickness dimension can be prevented by directing the bending direction of the tips of the tooth portions 2A and 2B in the opposite direction.

  Further, as shown in FIG. 8, all the teeth portions 2 are integrally formed with an annular core back member 9, and the width dimension in the radial direction of the inter-segment core back 6 disposed between the segments 5 is defined as the segment. You may decide to form smaller than the core back part 20 in 5.

  Further, the coil 4 may be wound around all the tooth portions 2, 2 </ b> A, 2 </ b> B, or the coil 4 may be wound only at the center tooth portions 2, 2 </ b> A or only on the tooth portions 2, 2 </ b> B on both sides. By winding the coil 4 around more teeth 2 parts, the number of turns of the coil 4 wound around one tooth part 2 can be reduced, and the thickness dimension of the stator 11 can be suppressed.

  Further, in the present embodiment, the number of the teeth portions 2, 2 </ b> A, 2 </ b> B is 18 and the number of magnetic poles of the permanent magnet 13 is 16, but the number of magnetic poles may be 20 instead. Alternatively, the number of teeth 2, 2A, 2B may be 27, and the number of magnetic poles may be 24 or 30.

Moreover, in this embodiment, although the segment 5 was provided with the three teeth parts 2, it is not limited to this.
Further, in the present embodiment, among the three tooth portions 2 provided on the segment member 8, the tooth tip widths of the central tooth portions 2, 2 </ b> A are formed larger than the tooth tip widths of the tooth portions 2 on both sides thereof. A structure in which all the teeth portions 2, 2A, 2B have the same tooth tip width or the same cross-sectional area may be adopted.

It is a top view which shows the stator structure which concerns on the 1st Embodiment of this invention. It is a side view which shows the teeth part of the stator structure of FIG. It is a top view which shows a motor provided with the stator core which has the stator structure of FIG. It is a longitudinal cross-sectional view which shows a disk type recording apparatus provided with the motor of FIG. It is a figure explaining the magnetic flux formed in a segment in the motor of FIG. FIG. 7 is an exploded perspective view showing a modification of the stator structure of FIG. 1. It is a top view which shows the stator structure of FIG. FIG. 10 is a plan view showing another modification of the stator structure of FIG. 1.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Stator structure 2, 2A, 2B Teeth part 3 Stator core 4 Coil 5 Segment 6 Inter-segment core back 10 Motor 11 Stator 12 Rotor 13 Permanent magnet 15 Disc type recording device 16 Recording medium 20 Core back part

Claims (8)

A plurality of teeth portions adjacent to each other in the circumferential direction, and a core back portion that connects these teeth portions in the circumferential direction, and a plurality of segments arranged in the circumferential direction and a segment connecting the adjacent segments in the circumferential direction A stator core with a core back;
A coil wound around the teeth portion of the stator core,
The segment includes three teeth portions adjacent in the circumferential direction,
In each of the segments, the tooth tip width of the center tooth portion is configured to be larger than the tooth tip widths of the tooth portions on both sides thereof,
A stator structure in which the inter-segment core back has a smaller cross-sectional area than the core back portion , and suppresses the inflow of magnetic flux between the adjacent segments to prevent magnetic flux saturation from occurring in the tooth portions on both sides . The core back portion is integrally formed of the same steel plate as the tooth portions on both sides,
The inter-segment core back is integrally formed by another steel plate that is the same as the central tooth,
The stator core has the core back portion and the inter-segment core back in the thickness direction so that the bending direction of the tip of the central teeth portion is opposite to the bending direction of the tips of the teeth portions on both sides. The stator structure according to claim 1, wherein the stator structure is formed in an overlapping manner. The core back portion is formed by a laminated steel plate obtained by laminating steel plates,
The stator structure according to claim 1, wherein the inter-segment core back is formed of at least one steel plate of the laminated steel plates and has a smaller cross-sectional area than the core back portion. The stator structure according to any one of claims 1 to 3, wherein segments adjacent in the circumferential direction constitute phases different from each other. The stator structure according to any one of claims 1 to 4 , wherein a thickness dimension of the inter-segment core back is smaller than a thickness dimension of the core back portion. The stator structure according to any one of claims 1 to 5 , wherein a width dimension of the inter-segment core back is smaller than a width dimension of the core back portion. A stator having the stator structure according to any one of claims 1 to 6 ,
A motor comprising a rotor provided with a permanent magnet configured in a ring shape by facing a tip of the teeth portion of the stator with a minute gap in the radial direction and alternately arranging different magnetic poles in the circumferential direction. A disk-shaped recording medium;
A disk-type recording apparatus comprising: the motor according to claim 7 that rotationally drives the recording medium.

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