JP2011114989A - Rotary electric machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rotary electric machine with stable rotation characteristics wherein a plurality of division cores are arranged annularly around the rotor and the cooling property is enhanced by each division core itself, and instability of reluctance between the division cores is solved. <P>SOLUTION: The rotary electric machine includes a pair of first and second bracket members facing each other, a magnet rotor with a rotating shaft bearing supported by the pair of brackets, a stator supported by the pair of brackets to form a plurality of magnetic teeth on the periphery of the magnet rotor, and a fastening member coupling the pair of brackets, wherein the stator is arranged annularly around the magnet rotor and constituted of a plurality of division cores formed by laminating electromagnetic steel plates and a winding wound around the respective division cores with an insulator interposed therebetween, and at least one of the pair of first and second brackets is formed of an annular magnetic material for magnetically coupling the division cores. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

The present invention relates to a rotating electrical machine in which a stator such as an electromagnetic motor or a generator is formed with a split core.

In general, rotating electric machines such as DC motors and generators are composed of a rotor and a stator having a rotating shaft. In an inner rotor type rotating electric machine, a magnet rotor is rotatably supported by a housing and a stator coil is provided on the outer periphery of the rotor. Structures arranged in a ring are widely known.

For example, as shown in FIG. 9 (a), there is known a rotating electrical machine having an appearance in which a stator core C is sandwiched between a pair of end brackets E1 and E2 made of aluminum die cast and a rotating shaft R1 protrudes from the center. Yes. The stator core C has a shape shown in FIG. 9B as disclosed in, for example, Patent Document 1 (Japanese Utility Model Publication No. 6-60284).

This stator core C is a single piece in which a thin plate material C2 made of a magnetic material is pressed, and a portion in which a rotor R is rotatably accommodated in a central portion, a magnetic pole portion C1, and a portion in which a stator coil is wound are arranged. The required number of magnetic plates are stacked. The rotor R includes a magnet rotor R2 and a rotation shaft R1.

Utility Kaihei 6-60284

As described above, the plurality of magnetic pole portions of the stator core made of a single magnetic plate obtained by punching out a thin plate made of a magnetic material by pressing are respectively projected toward the center. Therefore, the stator coil wound around the plurality of magnetic pole portions is very difficult to wind, and the automatic winding machine for automatic winding is complicated and quite expensive.

Therefore, in order to make it easy to wind a stator coil even with an ordinary automatic winding machine, each magnetic pole part of the stator core is formed by a divided core, and the stator coil is wound around each divided core. Later, the divided cores are combined to form one stator core.

However, when the stator core is formed of a plurality of divided cores, the magnetic resistance increases at the joints between the divided cores, making it difficult to form a magnetic circuit, causing magnetic instability, and causing rotation spots. .

  The present invention focuses on a pair of end brackets sandwiching a stator core in a sandwich shape with a rotating electric machine formed by combining a plurality of divided cores as a single stator core, and magnetically connecting the divided cores using the end brackets. Thus, the problem is to provide a rotating electrical machine that eliminates magnetic instability and has stable rotational characteristics free from rotational spots.

  In order to achieve the above object, a rotating electrical machine according to the present invention includes a pair of first and second bracket members facing each other, a magnet rotor having a rotation shaft supported by the pair of brackets, and a plurality of outer periphery of the magnet rotor. A stator supported by the pair of brackets so as to form a magnetic tooth, and a fastening member for connecting the pair of brackets, and the stator is arranged in an annular shape around the magnet rotor, and each has an electromagnetic steel plate. A rotating electrical machine comprising a plurality of stacked split cores and a winding wound around each of the split cores via an insulator, wherein at least one of the pair of first and second brackets is It is formed of an annular magnetic body that magnetically connects the divided cores.

Further, at least one of the pair of first and second brackets is integrally formed of a magnetic material.

Further, at least one of the pair of first and second brackets formed of the magnetic body is formed of an aluminum die-cast bracket body and an annular magnetic member fitted to the bracket body.

Still further, the outer ends of the plurality of split cores constitute an outer wall of the apparatus, and the outer ends are formed by forming partially protruding cooling fins.

As described above, the present invention is a rotating electrical machine in which a plurality of split cores are combined to form a single stator core, and at least one of a pair of end brackets sandwiching the stator core in a sandwich shape is magnetically coupled between the split cores. By forming the magnetic cores and magnetically connecting the divided cores, it is possible to eliminate the magnetic instability and provide a rotating electrical machine having stable rotational characteristics free from rotational spots.

In addition, as a result of magnetically connecting the split cores using end brackets, it is not necessary to enclose the split cores with a yoke case, and the end surfaces of the split cores can be configured as the outer wall surface of the device, and partly protrudes from the outer end By forming the cooling fins, the heat generated inside the apparatus can be efficiently and spontaneously released, the heat loss can be reduced, and the rotation efficiency can be increased.

It is explanatory drawing of the rotary electric machine concerning this invention, (a) shows a longitudinal cross-section, (b) is a perspective view of a core member, (c) is a structure figure of a core piece. FIG. 3 is an explanatory diagram of the structure of the stator shown in FIG. 1. It is explanatory drawing which shows the structure of a split core, (a) shows a connection state, (b) is explanatory drawing of an angle reference plane, (c) is the positioning block diagram of a 1st bracket. Split core laminated chain shape bracket support state diagram. It is explanatory drawing which shows 1st Embodiment of the 2nd bracket of FIG. 4, (a) shows a vertical section, (b) is an enlarged view of a 2nd contact surface. Explanatory drawing which shows 2nd Embodiment of the 2nd bracket different from FIG. Magnetic circuit structure explanatory drawing by a division | segmentation core and a bracket. The characteristic comparison figure of the rotary electric machine of this invention. Explanatory drawing of the conventional rotary electric machine.

  Hereinafter, the present invention will be described in detail based on preferred embodiments. First, the configuration of the rotating electrical machine according to the present invention will be described. As shown in FIG. 1A, the rotating electrical machine (hereinafter referred to as “motor”) M includes a rotor 10, a stator 20, a first bracket 30, a second bracket 40, and an outer casing (not shown). The The rotating electrical machine M shown in FIG. 1A is a brushless three-phase DC motor, and the present invention will be described below along the structure.

[Rotor configuration]
The rotor 10 includes a rotating shaft 11, a rotor core 12 formed integrally with the rotating shaft 11, and a magnet 13 formed on the outer periphery of the rotor core 12. The rotating shaft 11 is made of a metal material or other rod having a strength that can withstand a rotational load. The rotor core 12 is configured by molding a ferromagnetic metal powder such as iron powder, and is formed integrally with the rotating shaft 11. A magnet 13 is embedded in the outer periphery of the rotor core 12, and in the illustrated example, multiple magnetic poles of a multiple of 3 are formed. As for this magnetic pole, NS poles are alternately arranged at equal intervals on the outer periphery of the rotor. The magnet 13 is made of neodymium, ferrite, rare earth cobalt, and the like, and 8 poles, N poles, and S poles are alternately arranged around the rotor core 12 at equal intervals (45 degree intervals).

[Stator configuration]
The stator 20 is annularly arranged so as to surround the periphery of the rotor, and is configured by connecting a plurality of divided cores 21 (21a to 21l) in an annular shape. A winding wire 23 is wound around each of the split cores 21 a to 21 l via an insulator 22. As will be described later, the split core 21 is formed by laminating electromagnetic steel plates, for example, silicon steel plates obtained by adding silicon to iron in a stacked manner. Usually, a rolled steel sheet is punched into a predetermined shape with a press die to form the core piece 21x. A plurality of (for example, 50) core pieces 21x are stacked to form a core member. The insulator 22 is fitted into the core member, and the winding wire 23 is wound thereon. The number of turns of the winding wire 23 is determined in advance by a design value.

  In the illustrated embodiment (see FIG. 2), the divided core 21 is composed of 12 pieces (multiples of 4 in relation to a three-phase DC motor), and is arranged in a ring shape at intervals of 30 degrees, and each core piece 21x is interposed via an insulator 22. Winding wires 23a, 23b,... 231l are wound. In the twelve divided cores 21, the windings 23 having the same phase facing each other are connected to each other, and the three-phase divided cores 21a, 21e, and 21i are connected to the input terminals T1, T2, and T3 (see FIG. 2). . Therefore, the three-phase split cores 21a, 21e, and 21i need to be positioned at accurate angular positions around the rotor 10 at intervals of 120 degrees.

[Bracket configuration]
The rotor 10 and the stator 20 are fixed to the pair of first bracket 30 and second bracket 40. As shown in FIG. 1, the pair of first and second brackets 30 and 40 are connected to each other by a fastening member (a connecting bolt is shown in the figure) 50 to fix the rotor 10 and the stator 20 as follows. First, the rotating shaft 11 of the rotor 10 is rotatably supported by a bearing 31 provided on the first bracket 30 and two bearings 41 of the second bracket 40 at a predetermined distance (interval L). At the same time, the bearings 31 and 41 are provided with steps 32 and 42, and the steps 32 and 42 regulate the position of the positioning step (E-ring) 11e formed on the rotary shaft 11. As a result, the position of the rotor 10 is restricted by the first and second brackets 30 and 40 in the radial direction and the thrust direction, respectively.

  The first and second brackets 30 and 40 fix the stator 20 as follows. First, the structure of the stator 20 will be described. As described above, the stator 20 has a plurality of divided cores 21a to 21l (12 in the illustrated three-phase motor embodiment), an electromagnetic steel plate (for example, a silicon steel plate) having an appropriate shape. The core piece 21x is formed by stacking in a laminated shape. As shown in FIG. 1C, each of the core pieces 21x has a substantially fan-shaped cross section, and a plurality of (several dozen) pieces are overlapped to form one divided core 21.

  And the recessed part 21y and the convex part 21z are formed in the mutually adjacent site | part, and it connects with the chain form by fitting each other. The core piece 21x is provided with a coil winding portion 21w and a flange portion 21v, and a winding wire 23 is wound around the coil winding portion 21w with an insulator 22 interposed. The flange portion 21v is fixed to the first and second brackets 30 and 40.

  Further, in the illustrated example, an angle reference surface 21u is formed on the core piece 21x shown in FIG. The illustrated angle reference surface 21u is provided on a convex portion formed on the flange portion 21v of the core piece 21x, and engages with a positioning protrusion 34 formed on a first contact surface 33 of the first bracket 30 described later. As a result, the plurality of split cores 21a to 21l connected to each other in an annular shape are aligned at angular positions defined in the first bracket 30 described later.

  Furthermore, the above-described split core 21 is fixed to the first and second brackets 30 and 40 as follows. One of the brackets (first bracket 30) is formed with a first contact surface 33 that abuts and regulates one end surface (Sra shown in FIG. 4B) of the split core 21 in which the core pieces 21x are stacked in a stacked manner. ing. The first contact surfaces 33 are formed radially on the ring-shaped (annular) first bracket 30 according to the number of the split cores 21. The first contact surface 33 is configured by a plane that is in surface contact with the one end surface Sra of the split core 21.

In addition, each flange part 21v which forms the convex part protruded outward from each core piece 21x fulfills the effect as a cooling fin by projecting from the apparatus outer wall part, and efficiently generates heat generated inside the apparatus. To reduce heat loss and increase rotational efficiency

  In addition, the first bracket 30 is provided with a positioning projection 34 that regulates the angular position of the split core 21 (angular position in the rotor rotation direction). The positioning protrusions 34 are arranged at three positions at equal intervals of 120 degrees because the illustrated apparatus is a three-phase motor, and the angle reference plane 21u of the divided core 21 is made to coincide with this position.

  On the other hand, the other abutment surface 43 (second bracket 40) is formed with a second abutment surface 43 that abuts and regulates the other end surface (Srb shown in FIG. 4B) of the split core 21. The second contact surfaces 43 are also formed radially on the second bracket 40 having an annular cross section according to the number of the split cores 21. The second contact surface 43 is shown in FIGS. 5A and 5B, and FIG. 6 shows the second embodiment.

[Structure of the first and second brackets]
First, as shown in FIG. 5 (a), the first bracket 30 is an annular ring body made of a magnetic material that contacts and holds the bottom surface of the split core 21 on a bracket cover 30a formed by aluminum die casting. (Magnetic member) It consists of a structure fitted with 30b. In order to obtain a cooling effect, the annular ring body 30b forms a magnetic loop with the split core 21 in order to form the outer wall of the apparatus, thereby achieving magnetic stabilization of the split core 21. Similarly, in the second bracket 40, an annular ring body (second magnetic member) 40b made of a magnetic material is fitted to a bracket cover 40a formed by aluminum die casting at a position facing the upper surface of the split core 21. Consists of a structure. This annular ring body 40b is arranged at a position where it is not affected by the variation in the dimensions of the split cores 21 and can receive a magnetic action when forming the outer wall portion of the device in order to obtain a cooling effect in assembling the device. The divided core 21 is formed with a magnetic loop, and the divided core 21 is magnetically stabilized. Although the first and second bracket covers 30a and 40a and the annular ring bodies (first and second magnetic members) 30b and 40b are configured separately, they are configured as an integral member made of a magnetic material. Alternatively, a structure in which only one of the first and second bracket covers 30a and 40a is provided with a magnetic body or an annular ring body made of a magnetic material by a magnetic action may be used.

[Magnetic action of the first and second brackets]
In this way, the first bracket 30 and the second bracket 40 are each made of a magnetic material, and in the case of three-phase driving, the two divided cores 21 adjacent to each other as shown in FIG. A current is supplied to the winding 23 and each divided core 21 is excited. As a result, the rotor 10 is rotated in the direction of the arrow by being pulled by the excitation pole. In the state shown in the figure, for example, the south pole is excited on the opposite surface of the rotor 10 of the split core 21l, the north pole is excited on the outer wall surface, the north pole is on the opposite surface of the rotor 10 of the adjacent split core 21a, and the south pole is on the outer wall surface. Excited to form the first magnetic loop G1. At the same time, as shown in FIG. 7B, the magnetic flux output from the split core 21l enters the split core 21a through the annular ring body 30b which is the magnetic body of the first bracket 30, and the magnetic flux output from the split core 21a is the rotor. A second magnetic loop G2 that returns to the split core 21l via 10 is formed. Similarly, the magnetic flux output from the split core 21l enters the split core 21a through the annular ring body 40b which is the magnetic body of the second bracket 40, and the magnetic flux output from the split core 21a passes through the rotor 10 to the split core 21l. A returning third magnetic loop G3 is formed. As described above, compared to the case where the magnetic loop is formed only by the first magnetic loop G1, the second magnetic loop G2 and the third magnetic loop G3 are formed in this configuration, and the magnetic path becomes larger. The magnetic flux leaking outside the apparatus is drastically reduced, so that the magnetic instability is eliminated and the rotor 10 can be smoothly rotated. still,

[Performance characteristics with magnetic bracket]
Actually, as shown in the characteristic diagram shown in FIG. 8, compared to the case where the first and second brackets 30 and 40 are non-magnetic, the current change flowing through the split core 21 is a characteristic that is almost linear. The linear region width of the rotational torque is also widened.

[First Embodiment of Second Bracket]
The second bracket 40 has a second contact surface 43 formed as follows on the second bracket 40 shown in FIG. The second contact surface 43 is an inclined surface that is in line contact with the other end surface Srb of the split core 21 and is formed in a ring shape. That is, the edge of the other end surface Srb of the split core 21 contacts at an acute angle with the truncated cone-shaped inclined surface formed on the bracket. At the same time, the second contact surface 43 is made of a soft metal material or a resin material (shown is an aluminum alloy) with respect to the split core 21 formed of the above-described electromagnetic steel sheet (silicon steel or the like). Thus, the second contact surface 43 formed on the second bracket 40 is made of a material that is deformed so as to be crushed by the edge portion of the split core 21 under the fastening force of the fastening member 50 described later.

  As described above, the second abutting surface 43 is formed in a ring shape with an inclined surface, but the illustrated inclined surface has a regular truncated cone shape as shown in FIG. The rotating shafts 11 are arranged radially so as to coincide with the axis xx of the rotating shaft 11. As will be described later, when the plurality of divided cores 21a to 21l are clamped by the contact surface 43 of the second bracket 40, the divided cores are arranged at equal distances around the axis xx of the rotation shaft. This is to prevent the magnetic teeth from being biased.

[Second Embodiment of Second Bracket]
Further, a second contact surface 43 is formed on the second bracket 40 shown in FIG. 6 as follows. The second contact surface 43 is constituted by a spacer member 45 attached to a second bracket (metal material) 40, and the spacer member 45 is in surface contact with the other end surface Srb of the split core 21. The spacer member 45 is made of a resin material having magnetic properties by mixing a magnetic material that easily deforms by the fastening force of the fastening member 50 acting on the other end surface Srb of the split core 21. Therefore, the magnetic instability caused by the split core 21 can be eliminated by forming a magnetic loop based on the magnetic characteristics, and there are dimensional variations in the split cores 21a to 21l arranged in an annular shape. However, due to its easily deformable characteristics, the contact surface is deformed so as to follow the end surface of the core, and no gap is formed between them.

  As described above, the first and second brackets 30, 40 that join the rotor 10 and the stator 20 are integrated by the fastening member (connection bolt) 50, and the interval L is determined by the thickness dimension of the divided core 21. In addition, the housing of the rotating electrical machine M is configured by being covered with a cylindrical yoke (not shown).

  Next, the operation of the present invention will be described. As shown in FIG. 1, the rotor 10 is composed of the rotating shaft 11 and the magnet 13 as described above, and N poles and S poles are alternately arranged on the outer periphery of the rotor core 12. The rotor 10 is rotatably supported by bearings 31 and 41 of first and second brackets 30 and 40 in which a rotating shaft 11 is integrated by a fastening member 50. As a result, the magnetic pole formed by the magnet 13 of the rotor 10 is supported so as to rotate along a predetermined circular locus. At the same time, the position of the rotor 10 in the axial direction (thrust direction) is positioned and supported by the E-ring 11e at the steps 32 and 42 of the rotary shaft 11.

  As shown in FIG. 2, the stator 20 is composed of a plurality of divided cores 21a to 21l, and each of the divided cores 21a to 21l is fitted and connected by a concave portion 21y and a convex portion 21z formed in the core piece 21x. It is connected. Therefore, as shown in FIGS. 4B and 5A, each of the split cores 21a to 21l has a first end surface Sra of the first bracket 30 (annular ring body (first magnetic member) 30b). They are arranged in an annular shape with the contact surface 33 as a reference. At this time, the chained divided cores 21 have their angle reference surfaces 21 u aligned with the positioning protrusions 34 of the first bracket 30. As a result, the plurality of divided cores 21a to 21l can be positioned and arranged so that the end surfaces Sra thereof are aligned on the same plane, and the angular positions of the plurality of divided cores 21 linked in an annular shape are simultaneously positioned at predetermined positions. It becomes possible.

  Further, the other end surface Srb of the above-described split core 21 is pressed and supported by the second contact surface 43 of the second bracket 40 as shown in FIG. At this time, the second contact surface 43 is formed of an inclined surface (first embodiment) or a spacer member (second embodiment), and the second contact surface 43 is a material softer than the electrical steel sheet constituting the split core 21. Therefore, even if the thickness dimension between the plurality of split cores 21a to 21l varies, the second contact surface 43 is deformed and a gap or play between the other end surface Srb of the split core 21 is generated. There will be no spoil.

  Further, the second abutting surface 43 is formed as an inclined surface, and the inclined surface has a regular conical shape so that the vertex O coincides with the axis xx of the rotating shaft 11. As a result, the plurality of divided cores 21a to 21l can be arranged radially about the axis xx of the rotation shaft 11. This arrangement is automatically aligned by fastening the pair of first and second brackets 30 and 40 with the fastening member 50.

  Further, when the rotor 10 and the split core 21 are fixed between the first and second brackets, the magnetic force generated in the winding 23 of the stator 20 is the displacement force in the direction of the rotation axis (F shown in FIG. 4B). The displacement force F is set in a direction in which the rotor 10 is deflected toward the first contact surface 33 side of the first bracket 30.

  In this way, by displacing the positional relationship between the rotor 10 and the split cores 21a to 21l in the rotational axis direction by a predetermined distance, a displacement force in a direction biased toward the first contact surface 33 (reference surface) is applied to the rotor 10. However, since the split core 21 is aligned with this reference plane, no force that causes axial backlash during the rotation of the rotor 10 is applied.

  The present invention relates to a stator structure such as an electromagnetic motor and a generator, and a stator fixing structure provided with a coil related to a rotating electric machine using the same, and has industrial applicability.

M Rotating electric machine (motor)
10 Rotor 11 Rotating shaft 12 Rotor core 13 Magnet 20 Stator 21 Split core (21a to 21l)
30 1st bracket 30a Bracket cover 30b Annular ring body (first magnetic member)
40 Second bracket 40b Annular ring body (second magnetic member)

Claims (4)

A pair of first and second bracket members facing each other;
A magnet rotor having a rotation shaft supported by a pair of brackets;
A stator supported by the pair of brackets so as to form a plurality of magnetic teeth on the outer periphery of the magnet rotor;
A fastening member for connecting the pair of brackets;
With
The stator is
A plurality of split cores arranged in a ring around the magnet rotor and laminated with magnetic steel sheets, and
A winding wound around each of these split cores via an insulator;
A rotating electric machine composed of
At least one of the pair of first and second brackets is formed of an annular magnetic body that magnetically connects the divided cores. 2. The rotating electrical machine according to claim 1, wherein at least one of the pair of first and second brackets is integrally formed of a magnetic material. 2. The rotating electrical machine according to claim 1, wherein at least one of the pair of first second brackets formed of the magnetic body includes a bracket body and an annular magnetic member fitted to the bracket body. The outer ends of the plurality of split cores constitute an outer wall of the device,
The rotating electrical machine according to claim 1, wherein the outer end is formed with a partially protruding cooling fin.