JP5852345B2 - Rotor and motor - Google Patents

Description

The present invention relates to a rotor and a motor .

Conventionally, a so-called IPM type rotor in which a rotor core has a through hole and a magnet is disposed in the through hole is widely known (see, for example, Patent Document 1).
The rotor of Patent Document 1 is configured by laminating a plurality of core sheets to form a rotor core, and in this core sheet, a short protruding inside the punched hole for the magnet with a length dimension greater than the gap between the magnet and the hole. A protrusion (claw) is provided, and the magnet is held by the protrusion.

Japanese Patent No. 3675037

  By the way, in the rotor as described above, the rotor core is provided with a short projecting portion that projects with a length that is greater than the gap between the magnet and the hole, and holds the magnet. However, since the gap is relatively narrow, the protruding portion tends to be shortened, and there is a possibility that the magnet is damaged by the protruding portion when the magnet is inserted into the hole.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a rotor and a motor that can be held while suppressing damage to a magnet in a through hole.

In order to solve the above-mentioned problem, an invention according to claim 1 is a rotor including a rotor core having a through hole and a magnet inserted and disposed in the through hole of the rotor core, wherein the magnet is the magnet. A recess is formed in the magnetizing direction and extending in an axial direction perpendicular to the magnetizing direction and opening in an axial end surface of the magnet, and is inserted between the recess and the through hole. And a biasing means for pressing and biasing the magnet by pressing the magnet , wherein the biasing means is formed in such a manner that a part of the plate-like member provided on the end face of the rotor core is bent in the axial direction. The gist.

In the present invention, the magnet is formed with a recess in the magnetizing direction of the magnet and a recess extending in the axial direction perpendicular to the magnetizing direction and opening in the axial end surface of the magnet. And it is provided between the said recessed part and the said through-hole, and the biasing means which presses and biases the said magnet by pressing the said recessed part is provided. Thus, by forming the recess in the magnet, the distance between the through hole and the magnet can be increased. This makes it possible to sufficiently lengthen the urging means even when forming a conventional urging means such as a claw, and to prevent damage to the recess by the urging means.
Further, since the urging means is formed in such a manner that a part of the plate-like member provided on the end face of the rotor core is bent in the axial direction, it is possible to prevent the magnet from falling off in the axial direction with only the plate-like member.

The gist of the invention described in claim 2 is that, in the rotor according to claim 1, the recess is formed at the center in the width direction of the magnet.
In this invention, since the concave portion is formed at the center in the width direction of the magnet, when the concave portion is pressed by the biasing means, the center position in the width direction suitable for weight balance can be pressed, so the magnet can be held stably. It becomes possible to do. Moreover, since it is the center in the width direction of the magnet, the magnetic flux balance is good.

  According to a third aspect of the present invention, in the rotor according to the first or second aspect, the concave portion has an arc shape when viewed in the axial direction, and the urging means is formed in an arc shape along the concave portion. Is the gist.

  In this invention, the concave portion has an arc shape when viewed in the axial direction, and the urging means is formed in an arc shape along the concave portion, so that the contact between the concave portion and the urging means is a surface contact, and the concave portion by the urging means (Magnet) damage can be further suppressed.

The gist of the invention described in claim 4 is that, in the rotor according to claim 1 or 2, the urging means is configured to come into contact with the recess at two or more points.
In this invention, since the urging means is configured to come into contact with the concave portion at two or more points, even if a molding error occurs when the urging means or the concave portion is formed, the urging means is in a stable position. The depression can be pressed.

According to a fifth aspect of the present invention, in the rotor according to any one of the first to fourth aspects, the plate-like member includes an axial urging unit that urges the magnet in the axial direction. Is the gist.
In this invention, the plate-like member can regulate the movement of the magnet in the axial direction by including the axial biasing means that presses and biases the magnet in the axial direction.

According to a sixth aspect of the present invention, in the rotor according to any one of the first to fifth aspects, the plate-like member is made of a magnetic material, and is an outer surface of the magnet orthogonal to the magnetizing direction of the magnet. It is the gist that it is configured in a separated state.

  In this invention, the plate-like member is made of a magnetic material and is in a state of being separated from the outer surface of the magnet perpendicular to the magnetizing direction of the magnet. Accordingly, the magnetic permeability of the rotor can be improved, and the plate-like member made of a magnetic material and the magnet do not contact (separate) on the outer surface of the magnet perpendicular to the magnetizing direction of the magnet. Therefore, the magnetic flux generated by the magnet can be reliably used as the rotational force of the rotor.

According to a seventh aspect of the present invention, in the rotor according to the sixth aspect, the urging means is formed in such a manner that it is bent from the side opposite to the stator of the magnet at the center in the circumferential direction of the magnet. The gist.
In the present invention, the urging means is formed in such a manner that it is bent from the opposite side of the magnet at the center in the circumferential direction of the magnet. Here, a gap is generated in the plate-like member after being cut and raised to the inner diameter side at the center in the circumferential direction of the magnet, but the magnetic flux flows from the inner peripheral surface on the opposite side of the magnet to both sides in the circumferential direction. In addition, the effect of using a plate-like member as a magnetic material is exhibited more than the magnetic resistance.
The gist of a motor according to an eighth aspect is that the rotor according to any one of the first to seventh aspects is provided.

Therefore, according to the above-described invention, it is possible to provide a rotor and a motor that can be held while suppressing damage to the magnet in the through hole.

It is sectional drawing of the motor in this embodiment. It is sectional drawing of the rotor and stator in the same as the above. It is sectional drawing of the rotor in the same as the above. It is a principal part enlarged view of the rotor in the same as the above. It is a principal part enlarged view of the rotor in another example. (A) is a principal part enlarged view of the rotor in another example, (b) is AA sectional drawing in (a). It is a principal part enlarged view of the rotor in another example. It is sectional drawing of the rotor in another example.

DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, an embodiment of the invention will be described with reference to the drawings.
As shown in FIG. 1, a motor case 11 constituting the motor 10 of the present embodiment includes a case main body 12 and a substantially disc-shaped cover plate 13 that closes an opening of the case main body 12. .

  The case main body 12 having a bottomed cylindrical shape includes a cylindrical cylindrical portion 12a, a closing portion 12b that closes one end in the axial direction of the cylindrical portion 12a (the upper end in FIG. 1), and the cylindrical portion 12a. It is comprised from the annular flange part 12c extended in the radial direction outer side from the other end part of an axial direction. The cylindrical portion 12a, the closing portion 12b, and the flange portion 12c are integrally formed. Further, the case body 12 of the present embodiment is formed by pressing a metal plate material. The cover plate 13 is fixed to the flange portion 12 c of the case body 12, whereby the opening of the case body 12 is closed by the cover plate 13.

  A cylindrical stator 21 is fixed to the inner peripheral surface of the cylindrical portion 12a. The stator 21 includes a cylindrical stator core 22 and a coil 23 wound around the stator core 22.

  As shown in FIGS. 1 and 2, the stator core 22 includes a cylindrical stator fixing portion 22a fixed to the cylindrical portion 12a and the coil 23 wound around the stator fixing portion 22a so as to extend radially inward. And a plurality of teeth 22b. The stator core 22 is composed of a plurality (12 in this embodiment) of divided cores 24 that are arranged in the circumferential direction and have teeth 22b.

  As shown in FIG. 2, each divided core 24 includes a divided fixing portion 24 a having an arc shape when viewed from the axial direction, and the teeth 22 b extending radially inward from the inner peripheral surface of the divided fixing portion 24 a. It is configured. In each divided core 24, the teeth 22b extend radially inward from the central portion in the circumferential direction of the divided fixing portion 24a, and each divided core 24 has a substantially T-shape when viewed in the axial direction. Moreover, the division | segmentation fixing | fixed part 24a and the teeth 22b are formed equally in the width | variety of an axial direction.

  As shown in FIG. 2, the plurality of split cores 24 are formed such that the tips of the teeth 22b face radially inward, and the cylindrical stator fixing portions 22a are formed by the split fixing portions 24a. The stator core 22 is formed by being connected.

  A rotor 31 is disposed inside the stator 21. The rotor 31 includes a columnar rotation shaft 32, a rotor core 33 fixed to the rotation shaft 32 so as to be integrally rotatable, and a plurality of (four in this embodiment) magnets 34 held by the rotor core 33. It is configured.

  The rotating shaft 32 is made of a magnetic material and has a cylindrical shape. The base end portion (the upper end portion in FIG. 1) on the opposite side of the rotating shaft 32 is pivotally supported by a bearing 32a provided at the central portion in the radial direction of the closing portion 12b. On the other hand, the front end portion, which is the output side, of the rotary shaft 32 is pivotally supported by a bearing 32 b provided at the radial center of the cover plate 13. The rotating shaft 32 is arranged concentrically with the stator core 22 on the radially inner side of the stator core 22. Further, the distal end portion of the rotating shaft 32 penetrates the central portion in the radial direction of the cover plate 13 and protrudes (exposes) to the outside of the motor case 11 to form an output shaft.

  As shown in FIGS. 1 and 2, the rotor core 33 includes a core body 35 formed by laminating a plurality of core sheets formed by stamping a metal plate made of a magnetic material, and an axial direction of the core body 35. And a disk-shaped plate-like portion 36 provided at both ends. The rotor core 33 is configured by laminating the core body 35 and a plate-like portion 36 made of a magnetic material, and has a cylindrical fixing portion 33a and four pieces integrally formed with the fixing portion 33a on the outer periphery of the fixing portion 33a. Pseudo magnetic pole 33b.

  The fixing hole 33c formed in the central portion in the radial direction of the fixing portion 33a penetrates the fixing portion 33a in the axial direction, and the inner diameter of the fixing hole 33c is set slightly smaller than the outer diameter of the rotating shaft 32. .

  In addition, a through hole 37 that penetrates in the axial direction is formed in a portion between the pseudo magnetic poles 33b on the outer peripheral surface of the fixed portion 33a. A magnet 34 is inserted into the through hole 37. Each magnet 34 has a rectangular parallelepiped shape that is long in the axial direction of the rotor core 33, and the length in the axial direction is substantially equal to the length in the axial direction of the rotor core 33. In addition, a concave portion 41 is formed at the central position in the width direction (circumferential direction) of the magnet 34 and has a concave shape radially outward when the through-hole 37 is inserted. The recess 41 has a shape that communicates (opens) to the axial end surface of the magnet 34.

  As shown in FIGS. 1 to 3, the magnet 34 has a concave portion 41 formed by an urging portion 42 formed by being cut and raised in the axial direction from the plate-like portion 36 in a state of being inserted into the through hole 37. It is held by being pressed.

  In the present embodiment, these magnets 34 are magnetized so that the radially outer end is an N pole and the radially inner end is an S pole. Therefore, in the rotor 31 of the present embodiment, four magnets 34 of the N poles among the S poles and the N poles are arranged in the circumferential direction with respect to the rotor core 33. Then, by inserting each magnet 34 into the through hole 37, the pseudo magnetic pole 33 b is arranged between the magnets 34 adjacent in the circumferential direction, and as a result, the N-pole magnet 34 and the pseudo magnetic pole 33 b are arranged in the circumferential direction. Alternatingly arranged. By arranging the magnet 34 in this way with respect to the rotor core 33 having the pseudo magnetic pole 33b, the pseudo magnetic pole 33b functions as an S pole in a pseudo manner. That is, the rotor 31 of this embodiment is a continuous pole type rotor in which the magnet 34 of one magnetic pole and the pseudo magnetic pole 33b functioning as the other magnetic pole are alternately arranged in the circumferential direction.

  As shown in FIG. 1, an annular sensor magnet 38 is provided on the rotary shaft 32 at a position between the tip surface (lower end surface in FIG. 1) of the rotary shaft 32 and the rotor core 33. 32 is fixed so as to be rotatable together. The sensor magnet 38 is magnetized so that the N pole and the S pole are alternately arranged in the circumferential direction.

  A circuit board 39 on which circuit elements (not shown) for controlling the motor 10 are mounted is fixed to the inner surface of the cover plate 13. On the circuit board 39, a hall sensor 40 is disposed so as to face the sensor magnet 38 in the axial direction. The hall sensor 40 is a hall IC provided with a hall element. The circuit board 39 is electrically connected to a drive control circuit (not shown) provided outside the motor 10.

Next, a method for fixing (holding) the magnet 34 by the urging portion 42 of the plate-like portion 36 will be described.
First, the shape of the urging portion 42 before cutting and raising will be described in detail. The urging portion 42 has the axial length (thickness) of the plate-like portion 36, and the radial length is obtained by adding the radial length of the concave portion 41 and the axial separation distance of the magnet 34 and the through hole 37. Four biasing portions 42 are formed on each plate-like portion 36 in accordance with the number of magnets 34 inserted into the through holes 37.

  For example, in a state where a magnet is inserted into the through hole 37 of the rotor core 33, each urging portion 42 of the plate-like portion 36 disposed on both sides of the core body 35 is cut and raised in the axial direction on the core body 35 side. . The urging portion 42 cut and raised is inserted between the concave portion 41 and the through hole 37, and the urging portion 42 presses the concave portion 41 in the radial direction. As a result, the magnet 34 is sandwiched and held by the inner peripheral surface 37 a on the radially outer side of the through hole 37 and the urging portion 42.

Next, an operation example (action) of the motor 10 configured as described above will be described.
In the motor 10, when power is supplied to the coil 23, the rotor 31 is rotated according to the rotating magnetic field generated by the stator 21. The hall sensor 40 detects a change in the magnetic field of the sensor magnet 38 that rotates integrally with the rotation shaft 32 of the rotor 31 and outputs a rotation detection signal that is a pulse signal corresponding to the detected change in the magnetic field to the drive control circuit. To do. The drive control circuit detects rotation information (rotation speed, rotation position, etc.) of the rotor 31 based on the rotation detection signal. The drive control circuit controls the power supplied to the stator 21 based on the detected rotation information of the rotor 31 so that the rotation speed of the rotor 31 becomes a desired rotation speed. Accordingly, power is supplied from the drive control circuit to the coil 23 according to the rotation state of the rotor 31.

Next, characteristic effects of the present embodiment will be described.
(1) The magnet 34 is formed with a recess 41 that is concave in the magnetizing direction (radial direction) of the magnet 34 and that extends in the axial direction perpendicular to the magnetizing direction and opens in the axial end surface of the magnet 34. The And the biasing part 42 which presses and biases the magnet 34 by inserting between the recessed part 41 and the through-hole 37 and pressing the recessed part 41 is provided. Thus, by forming the recess 41 in the magnet 34, the distance between the through hole 37 and the magnet 34 can be increased. Thereby, the length of the urging portion 42 can be made sufficiently long to prevent damage to the concave portion 41 (magnet 34) by the urging portion 42.

  (2) Since the concave portion 41 is formed at the center in the width direction of the magnet 34, when the concave portion 41 is pressed by the urging portion 42, a suitable center position in the width direction of the weight balance and magnetic balance can be pressed. It becomes possible to hold the magnet 34 stably.

  (3) Since the urging portion 42 is formed in such a manner that a part of the plate-like portion 36 provided on the end surface of the core body 35 constituting the rotor core is bent in the axial direction, the magnet 34 tries to move in the axial direction. Also, the urging portion 42 of the plate-like portion 36 serves as a stopper, and can contribute to preventing the magnet 34 from falling off in the axial direction.

In addition, you may change embodiment of this invention as follows.
In the above embodiment, although not particularly mentioned, the urging portion 42 may be formed in an arc shape along the concave portion 41 having an arc shape as viewed in the axial direction as shown in FIG. By setting it as such a structure, the contact of the recessed part 41 and the urging | biasing part 42 turns into a surface contact, and damage to the recessed part (magnet) by the urging | biasing part 42 can be suppressed more.

  In the above embodiment, although not particularly mentioned, a configuration in which the urging portion 42 and the recess 41 are in contact at two or more points may be employed. As such a configuration, for example, as shown in FIG. 5, the shape of the concave portion 51 viewed in the axial direction is a trapezoidal shape, and the shape of the biasing portion 52 viewed in the axial direction is a curved shape. 51a and 51b will contact the urging | biasing part 52 at two points. For this reason, even if a molding error occurs when the urging portion 52 and the concave portion 51 are formed, the concave portion 41 can be pressed by the urging portion 52 at a stable position.

  In the above embodiment, although not particularly mentioned, for example, as shown in FIGS. 6A and 6B, axial urging portions 60 and 61 for pressing and urging the magnet 34 in the axial direction may be formed. . The axial urging portions 60 and 61 are provided on each of the two plate-like portions 36 disposed on both sides of the core body 35 in the axial direction. By setting it as such a structure, the movement to the axial direction of the magnet 34 can be controlled.

  In the above embodiment, although not particularly mentioned, a plate made of a magnetic material so as to be separated from the outer circumferential surfaces 34a and 34b, which are outer surfaces of the magnet 34 orthogonal to the magnetization direction. The shape portion 36 may be configured. Specifically, as shown in FIG. 7, a predetermined gap X is formed between the plate-like portion 36 and the outer circumferential surfaces 34a, 34b of the magnet 34 in the circumferential direction. Accordingly, the magnetic permeability of the rotor can be improved, and the outer surface of the magnet 34 (circumferential outer surface) that is perpendicular to the magnetization direction of the magnet 34 is obtained when the plate-like portion 36 and the magnet 34 made of a magnetic material are used. 34a and 34b) are not in contact (separated), so that the magnetic flux generated by the magnet 34 can be reliably used as the rotational force of the rotor. The urging portion 42 may be cut and raised (bent) from the inner diameter side of the magnet 34 in the circumferential direction center (width direction center). In this case, a gap 65 is formed at the center of the magnet 34 in the circumferential direction after being cut and raised toward the inner diameter side. Therefore, the effect of using the plate-like portion 36 as a magnetic material is exhibited more than the magnetic resistance.

-In above-mentioned embodiment, although the plate-shaped part 36 was comprised with the magnetic material, it is not restricted to this.
In the above embodiment, the urging portion 42 is provided on the plate-like portion 36. However, for example, as shown in FIG. 8, the plate-like portion 36 is omitted and the radial direction ( A configuration in which a spring member 70 that is elastically deformed in the magnetization direction of the magnet 34 may be employed.

  In the above embodiment, the rotor 31 is configured as a so-called continuous pole type. However, the configuration is not limited thereto, and a configuration in which magnets having different polarities are alternately arranged in the circumferential direction may be employed. In short, what is necessary is just a so-called IPM type rotor in which a magnet is embedded in the rotor core 33.

Next, a technical idea that can be grasped from the above embodiment and another example will be added below.
(B) motor, comprising the B over data.

Thereby, the motor which can have an effect similar to the effect by the above-mentioned rotor can be provided.

  DESCRIPTION OF SYMBOLS 21 ... Stator, 31 ... Rotor, 33 ... Rotor core, 34 ... Magnet, 36 ... Plate-shaped part (plate-shaped member), 37 ... Through-hole, 41, 51 ... Recessed part, 42, 52 ... Biasing part (biasing means) , 60, 61... Axial urging portion (axial urging means), 65... Clearance, 70.

Claims (8)

A rotor having a rotor core having a through-hole and a magnet inserted and arranged in the through-hole of the rotor core and arranged to face the stator in the radial direction,
The magnet is concave in the magnetizing direction of the magnet and has a recess extending in the axial direction orthogonal to the magnetizing direction and opening in the axial end surface of the magnet.
An urging means for pressing and urging the magnet by being inserted between the recess and the through hole and pressing the recess ;
The rotor, wherein the urging means is formed in such a manner that a part of a plate-like member provided on the end face of the rotor core is bent in the axial direction . The rotor according to claim 1, wherein
The said recessed part was formed in the width direction center of the said magnet, The rotor characterized by the above-mentioned. The rotor according to claim 1 or 2,
The concave portion has an arc shape when viewed in the axial direction,
The rotor, wherein the biasing means is formed in an arc shape along the recess. The rotor according to claim 1 or 2,
The rotor, wherein the biasing means is configured to contact the concave portion at two or more points. In the rotor according to any one of claims 1 to 4 ,
The said plate-shaped member is provided with the axial direction biasing means which presses and biases the said magnet to an axial direction, The rotor characterized by the above-mentioned. In the rotor according to any one of claims 1 to 5 ,
The said plate-shaped member is comprised with the magnetic material, and was comprised in the state spaced apart from the outer surface of the magnet orthogonal to the magnetization direction of the said magnet. The rotor according to claim 6 , wherein
The rotor is characterized in that the biasing means is formed in such a manner that it is bent from the opposite side of the magnet at the center in the circumferential direction of the magnet. A motor comprising the rotor according to claim 1.

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