JP2009296758A - Field element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a field element that facilitates the combination work of the field element and an armature. <P>SOLUTION: A magnetic plate 5 is arranged at the field element 2. A plurality of field element cores 21 located at the farther side apart from a rotating shaft Q from a permanent magnet 22 are arranged in the circumferential direction, and magnetically separated from one another with air gaps 23 therebetween. The magnetic plate 5 magnetically separates the field element cores 21 in a first position in which a fastening tool 66 is locked to the end 52c of a hole 52. The magnetic plate 5 magnetically connects the field element cores 21 in a second position in which the fastening tool 66 is locked to the end 52d of the hole 52. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a field element employed in a permanent magnet embedded motor that exhibits a so-called radial gap.

  A rotating electrical machine is generally composed of a stator and a rotor. When the stator is provided with an armature provided with an armature winding that generates a rotating magnetic field, and the rotor is provided with a field element provided with a permanent magnet that generates a field magnetic flux. There are many.

  A gap commonly referred to as an air gap is provided between the armature and the field element. The air gap is set small enough to allow the interaction between the rotating magnetic field and the field magnetic flux to function while allowing relative rotational movement between the rotor and the stator. As such an air gap, a so-called radial gap type in which a side surface of the air gap is perpendicular to the rotation axis of the rotor is often used.

  As the configuration of the field element, from the viewpoint of using reluctance torque, a permanent magnet embedded motor (also usable as an electric motor) in which a permanent magnet is provided inside the field element core is often employed.

  When a field element and an armature are combined to produce a radial gap type permanent magnet embedded motor having such a configuration, a direction parallel to the rotation axis (hereinafter referred to as “rotation axis direction”) is used. Insert one into the other. However, at this time, an attractive force acts between the permanent magnet of the field element and the teeth of the armature perpendicularly to the direction of the rotation axis. Therefore, the attraction force is a major obstacle to the work of combining the field element and the armature.

  In order to avoid such an obstacle, Patent Document 1 discloses a technique in which a permanent magnet of a field element is magnetized after combining an armature and a field element, or is incorporated into an armature while rotating the field element. Is disclosed.

  Patent Document 2 discloses a technique in which a member serving as a magnetic flux path moves so as to weaken the field when the electric motor rotates at high speed.

JP 2001-37171 A JP-A-11-275789

  However, in the method of magnetizing the permanent magnet of the field element after combining the armature and the field element, when the field element and the armature are disassembled along the rotation axis direction in order to perform maintenance of the electric motor. The above suction force works. In addition, the method of incorporating the armature into the armature while rotating the field element is considered to disassemble the field element and the armature in the same manner, but as described in paragraph 0020 of Patent Document 1, There is a need for a support device that supports the end of the rotor as a field element and a rotating device that can rotate at a speed sufficient to uniformly distribute the magnetic force.

  In the technique disclosed in Patent Document 2, the field is weakened during high-speed rotation of the motor, but the field is not weakened during assembly or maintenance of the motor.

  The present application has been made in view of the above-described viewpoints, and an object thereof is to provide a field element that can easily perform a work of combining a field element and an armature.

  A first aspect of the field element according to the present invention includes a plurality of first field element cores (21) arranged in the circumferential direction around a predetermined axis (Q) and the adjacent first field element cores. A plurality of permanent magnets (22) for supplying field magnetic fluxes having different polarities to the first field element core, and the first field element cores adjacent to each other in the first position. The magnetic cores are magnetically separated from each other, and the adjacent first field cores are magnetically connected to each other in the second position, and are movable between the first position and the second position. A magnetic plate (5).

  A second aspect of the field element according to the present invention is the first aspect, wherein a plurality of the magnetic plates (5) are arranged in the circumferential direction, and adjacent ones are magnetically separated from each other. It has magnetic pieces (50) mechanically connected. The magnetic plate moves in the circumferential direction between the first position and the second position. When the magnetic plate (5) is in the second position, the first of the pair of edges (51b) in the circumferential direction of each of the magnetic pieces covers the first in a plan view along the axis (Q). The first field element core (21) and the first field element core (21) covered with the other of the pair of edges are adjacent to each other.

  A third aspect of the field element according to the present invention is the first aspect, and is provided on a side opposite to the first field element core with respect to the permanent magnet (22) and functions as a back yoke. And a second field element core (24). The magnetic plate (5) magnetically separates the first field element core and the second field element core at the first position, and the first field element core and the second position at the second position. The second field element core is magnetically coupled.

  A fourth aspect of the field element according to the present invention is the third aspect, wherein a plurality of the magnetic plates (5) are arranged in the circumferential direction, and adjacent ones are magnetically separated from each other. It has magnetic pieces (50) mechanically connected. The magnetic plate moves in the circumferential direction between the first position and the second position, and when the magnetic plate (5) is in the first position, the permanent magnet (22) of each of the magnetic pieces. The side edge (51a) is located at the boundary between the permanent magnet and the first field element core, or closer to the first field element core than the boundary. When the magnetic plate (5) is in the second position, the side is adjacent to each other across the second field element core (24) in plan view along the axis (Q). The first field element core (21) that overlaps the first field element core and one of the pair of edges (51b) in the circumferential direction of each of the magnetic pieces overlaps, and the other of the pair of edges is The overlapping first field element cores (21) are adjacent to each other.

  A fifth aspect of the field element according to the present invention is any one of the second and fourth aspects, wherein the first field element is located laterally along the axis of the first field element core. A convex part (66) fixed to the core and projecting along the axis is further provided. The magnetic plate (5) has a hole (52) in the magnetic piece (50). The hole locks the convex portion when the magnetic plate is in the first position and the first end (52c) that locks the convex portion when the magnetic plate is in the first position. A second end (52d) and a guide edge (52a, 52b) for guiding the circumferential movement of the convex portion in the hole between the first end and the second end are provided as an extension.

  A field element according to a sixth aspect of the present invention is any one of the first to fifth aspects, wherein the first field element core is located on the opposite side of the axis with respect to the permanent magnet. To do.

  A seventh aspect of the field element according to the present invention is the sixth aspect, wherein the magnetic plate (5) connects the magnetic pieces (50) in a plane perpendicular to the axis (Q). And a nonmagnetic material.

  An eighth aspect of the field element according to the present invention is the sixth aspect, in which the magnetic plate (5) has a thickness different from other portions in the partial region (57).

  According to the first aspect of the field element according to the present invention, when the rotary electric machine is configured by combining the field element and the armature, the magnetic plate is moved to the second position. As a result, the permanent magnet is temporarily short-circuited, the generation of an attractive force between the permanent magnet and the armature core is suppressed, and the work of combining the field element and the armature becomes easy. After the rotating electrical machine is constructed, the short circuit of the permanent magnet is released and normal operation is performed. Since the first field element core is provided sideways along the axis, the structure is simpler than the structure in which the magnetic body for short-circuiting the permanent magnet is disposed inside the first field element core. is there. The magnetic plate also functions as an end plate for the steel plate when the first field element core is formed of laminated steel plates.

  According to the second aspect and the fourth aspect of the field element according to the present invention, the movement of the magnetic plate between the first position and the second position is simple.

  According to the 3rd aspect of the field element concerning this invention, the effect | action of the magnetic plate in a 2nd position increases.

  According to the fifth aspect of the field element of the present invention, the magnetic plate is easily guided and positioned in the circumferential direction to the first position and the second position.

  According to the seventh aspect of the field element of the present invention, the mechanical strength is increased without impairing the magnetic action of the magnetic plate.

  According to the eighth aspect of the field element of the present invention, the thickness deviation functions as a balancer that adjusts the center of gravity around the axis of the field element.

  FIG. 1 is a cross-sectional view showing a configuration of a radial gap type permanent magnet embedded motor that can employ a field element according to the present invention, and schematically shows a cross section perpendicular to the rotation axis Q of the motor.

  The motor includes an armature 4 that is a stator and a field element 2 that is a rotor surrounded by the armature 4.

  The armature 4 has a plurality of teeth 43, a yoke 42, and an armature winding 41 (drawn with a chain line to avoid complication of the drawing). The armature winding 41 is wound around each tooth 43. The teeth 43 have a wide portion 44 that extends in the circumferential direction on the field element 2 side. The wide portion 44 presents a surface 43 a that faces the field element 2. The teeth 43 are connected to each other by the yoke 42 on the side opposite to the wide portion 44.

  The field element 2 includes field element cores 21 and 24 and a permanent magnet 22. A plurality of field element cores 21 are arranged around the rotation axis Q in the circumferential direction. The permanent magnet 22 supplies a field magnetic flux to the field element core 21. The field magnetic fluxes respectively supplied to the adjacent field element cores 21 have different polarities.

  The field element core 24 is provided on the side opposite to the field element core 21 with respect to the permanent magnet 22 and functions as a back yoke. A shaft 30 extending in the direction of the rotation axis about the rotation axis Q is inserted through the field element core 24. The field element core 24 is provided with a through hole 64. When the motor using the field element 2 is mounted on the compressor, the through hole 64 functions as a passage for a compression target of the compressor (for example, a refrigerant of an air conditioner). When such a function is unnecessary, the through hole 64 is of course unnecessary.

  The field element core 24 and the shaft 30 are engaged by a wedge 31 so that they do not slide in the circumferential direction. As another method, the engagement with the wedge 31 may be omitted by press-fitting the field element core 24 into the shaft or shrink-fitting it.

  For example, the field element cores 21 and 24 are configured by laminating electromagnetic steel plates perpendicular to the rotation axis Q in the rotation axis direction. In this case, the field element core 21 is fastened in the direction of the rotation axis by the fastener 66. The fastener 66 may be provided on the field element core 24, or may be provided on both the field element cores 21 and 24. Further, each of the electromagnetic steel sheets desirably has the unevenness 65 in the field element core 21. The concave and convex portions 65 engage with each other between adjacent electrical steel sheets and perform a fastening function called “entanglement”.

  FIG. 2 is a side view showing a configuration of a radial gap type permanent magnet embedded motor that can employ the field element according to the present invention, and conceptually shows a side view of the motor viewed from a direction perpendicular to the rotation axis Q. ing.

  The motor also has a magnetic plate 5 that does not appear in FIG. The magnetic plate 5 is provided laterally along the rotation axis direction of the field element core 21. The fastener 66 also penetrates the magnetic plate 5. When the field element cores 21 and 24 are formed of laminated steel plates, the magnetic plate 5 functions as an end plate for the steel plates.

  In addition, when the field element cores 21 and 24 are not formed of a laminated steel plate, the fastener 66 need not be provided. However, it is desirable that a structure similar to the fastener 66 is provided for positioning the magnetic plate 5 in the circumferential direction as will be described later. Specifically, it is desirable to provide a protrusion that is fixed to the field element core 21 along the rotation axis direction of the field element core 21 and protrudes along the rotation axis. When the fastener 66 is provided, the function of the convex portion is secured by the fastener 66.

  FIG. 3 is a cross-sectional view showing the field element 2, schematically showing a cross section perpendicular to the rotation axis Q. The polarity of the field magnetic flux supplied from the permanent magnet 22 to the field element core 21 is indicated as “N” or “S” in the vicinity of the permanent magnet 22 of each field element core 21.

  Adjacent field element cores 21 are magnetically separated in the circumferential direction by a gap 23 extending substantially in the radial direction. However, structurally, adjacent field element cores 21 are connected to each other by a thin portion 26 on the side opposite to the rotation axis Q.

  The air gap 23 has a function of preventing the magnetic flux from flowing in a short circuit in the same permanent magnet 22 and a function of preventing the adjacent permanent magnet 22 from flowing in a short circuit via the adjacent field element cores 21. .

  The field element core 24 is magnetically separated from any field element core 21 by the air gap 23, but is structurally separated from the field element core 21 by the thin part 25 provided between the air gaps 23 via the thin part 26. Connected to

  However, the field element cores 21 and 24 may be separated from each other by the gap 23 without providing the thin portions 25 and 26. In this case, it is desirable to provide a separate mechanism for holding the field element core 21 against centrifugal force when the field element 2 rotates, such as the magnetic plate 5 holding the field element core 21.

  FIG. 4 is a plan view showing the magnetic plate 5, schematically showing a plane viewed along the rotation axis direction.

  The magnetic plate 5 has a plurality of magnetic pieces 50 arranged in the circumferential direction. Each of the magnetic pieces 50 presents a pair of edges 51b in the circumferential direction and a side 51a on the permanent magnet 22 side.

  Adjacent magnetic pieces 50 are mechanically coupled while being magnetically separated by the thin portion 51c. However, when the field element cores 21 and 24 are mechanically connected to each other, it is not always necessary to provide the thin portion 51c, and the magnetic pieces 50 may be separated from each other.

  A hole 52 is provided in the magnetic piece 50. The hole 52 has ends 52c and 52d and guide edges 52a and 52b as external extensions.

  FIG. 5 and FIG. 6 are diagrams for explaining the effect of the present embodiment, in which the field element 2 is shown with a cross section, the magnetic plate 5 is shown with a plane, and the rotation axis Q is overlapped. However, in order to avoid complication of the drawing, the magnetic plate 5 is drawn with a chain line. 5 and 6 can be almost grasped as a configuration in plan view as viewed along the rotation axis Q. However, although the end portion in the rotation axis direction of the fastener 66 is enlarged and fastens the magnetic plate 5 and the field element core 21, such an end portion does not appear in FIGS.

  FIG. 5 shows a state in which the end 52c locks the fastener 66, and FIG. 6 shows a state in which the end 52c locks the fastener 66. In the present embodiment, the positions of the magnetic plate 5 shown in FIGS. 5 and 6 are referred to as a first position and a second position, respectively. The guide edges 52a and 52b guide the circumferential movement of the fastener 66 in the hole 52 between the ends 52c and 52d.

  Thus, the magnetic plate 5 is movable in the circumferential direction between the first position and the second position. Specifically, various methods are conceivable, but it is also conceivable that the fastener 66 moves the magnetic plate 5 in the circumferential direction against the force of fastening the magnetic plate 5 to the field element core 21. The tightening force may be weakened to such an extent as to allow the above.

  As shown in FIG. 5, the magnetic plate 5 magnetically separates the adjacent field element cores 21 at the first position, and the adjacent field element cores 21 at the second position as shown in FIG. Magnetically coupled.

  Therefore, when the rotating electric machine is configured by combining the field element 2 and the armature 4 (see FIG. 1), the magnetic plate 5 is moved to the second position. As a result, the permanent magnet 22 is temporarily short-circuited, and the generation of an attractive force between the permanent magnet 22 and the armature core (for example, the teeth 43 shown in FIG. 1) is suppressed. 4 is easy to combine.

  After the rotating electrical machine is configured, the magnetic plate 5 is moved to the first position, the short circuit of the permanent magnet 22 is released, and the normal operation is performed.

  In addition, since the magnetic plate 5 is provided on the side along the rotation axis Q of the field element core 21, the configuration is such that a magnetic body for short-circuiting the permanent magnet 22 is disposed inside the field element core 21. It is simple compared.

  Further, when the magnetic plate 5 is in the second position, the field element core 21 covered by one of the edges 51b of the same magnetic piece 50 and the field covered by the other of the edges 51b in a plan view seen along the rotation axis Q. The child cores 21 are adjacent to each other. That is, the adjacent field element cores 21 are covered with the same magnetic piece 50 spreading in the circumferential direction. This is desirable from the viewpoint of realizing the movement of the magnetic plate 5 between the first position and the second position in a simple manner in which the magnetic plate 5 is moved in the circumferential direction.

  Further, it is desirable that the magnetic plate 5 magnetically separates the field element cores 21 and 24 from each other at the first position. Therefore, when the magnetic plate 5 is in the first position, each side 51a of the magnetic piece 50 is preferably located at the boundary between the permanent magnet 22 and the field element core 21 or closer to the field element core 21 than the boundary. .

  On the other hand, when the magnetic plate 5 is in the second position, the side 51a overlaps with a pair of field element cores 21 adjacent to each other across the field element core 24 in a plan view along the rotation axis Q. Is desirable. At this time, the field element core 21 covered by one of the edges 51b of the same magnetic piece 50 and the field element core 21 covered by the other edge 51b are adjacent to each other.

  Moreover, since the magnetic plate 5 magnetically connects the field element cores 21 and 24 to each other, the action of short-circuiting the permanent magnet 22 is great.

  Since the hole 52 has the guide edges 52a and 52b and the ends 51c and 51d, the magnetic plate 5 is easily guided and positioned in the circumferential direction to the first position and the second position.

  It is also desirable that the magnetic plate 5 further includes a nonmagnetic material that connects the magnetic pieces 50 in a plane perpendicular to the rotation axis Q. Specifically, the region surrounded by the side 51a and the edge 51b (see FIG. 4) is filled with resin or the like inside the thin portion 51c. This has the effect of increasing the mechanical strength without impairing the magnetic action of the magnetic plate 5.

  In addition, it is desirable that the magnetic plate 5 has a thickness different from other portions in the partial region 57 (see FIG. 4). This is because the thickness deviation functions as a balancer that adjusts the center of gravity of the field element 2 around the rotation axis Q.

  The above description describes a so-called inner rotor type motor in which the field element core 21 is located on the opposite side of the rotation axis Q with respect to the permanent magnet 22. Although the present invention can be applied to an outer rotor type motor, the outer rotor type has a small size in the radial direction of the field element. Therefore, when adopting a mode in which the holes 52 are provided in the magnetic plate 5, it is desirable to apply the present invention to the above-described inner rotor type motor.

It is sectional drawing which shows the structure of the motor which can employ | adopt the field element concerning this invention. It is a side view which shows the structure of the motor which can employ | adopt the field element concerning this invention. It is sectional drawing which shows a field element. It is a top view which shows a magnetic board. It is a figure explaining the effect of this Embodiment. It is a figure explaining the effect of this Embodiment.

Explanation of symbols

2 Field element 21, 24 Field element core 22 Permanent magnet 5 Magnetic plate 50 Magnetic piece 51a Side 51b Edge 57 Partial region Q Rotating shaft

Claims (8)

A plurality of first field element cores (21) arranged in a circumferential direction around a predetermined axis (Q);
A plurality of permanent magnets (22) for supplying field magnetic fluxes having different polarities to the adjacent first field element cores;
Next to the first field element core along the axis, the first field element cores adjacent to each other are magnetically separated at the first position, and adjacent to each other at the second position. A field element (2) comprising a magnetic plate (5) movable between the first position and the second position, wherein the first field element cores are magnetically coupled to each other. The magnetic plate (5) includes a plurality of magnetic pieces (50) that are arranged in the circumferential direction and mechanically connected while adjacent ones are magnetically separated from each other,
The magnetic plate moves in the circumferential direction between the first position and the second position;
When the magnetic plate (5) is in the second position, the first of the pair of edges (51b) in the circumferential direction of each of the magnetic pieces covers the first in a plan view along the axis (Q). The field element (2) according to claim 1, wherein the first field element core (21) and the first field element core (21) covered by the other of the pair of edges are adjacent to each other. A second field element core (24) provided on the opposite side of the first field element core with respect to the permanent magnet (22) and functioning as a back yoke.
Further comprising
The magnetic plate (5) magnetically separates the first field element core and the second field element core at the first position, and the first field element core and the second position at the second position. The field element (2) according to claim 1, wherein the field element (2) is magnetically coupled to the second field element core. The magnetic plate (5) includes a plurality of magnetic pieces (50) that are arranged in the circumferential direction and mechanically connected while adjacent ones are magnetically separated from each other,
The magnetic plate moves in the circumferential direction between the first position and the second position;
When the magnetic plate (5) is in the first position, the side (51a) on the permanent magnet (22) side of each of the magnetic pieces is the boundary between the permanent magnet and the first field element core, or Located closer to the first field element core than the boundary,
When the magnetic plate (5) is in the second position, the side is adjacent to each other across the second field element core (24) in plan view along the axis (Q). The first field element core (21) that overlaps the first field element core and one of the pair of edges (51b) in the circumferential direction of each of the magnetic pieces overlaps, and the other of the pair of edges is The field element (2) according to claim 3, wherein the overlapping first field element cores (21) are adjacent to each other. A convex portion (66) fixed to the first field element core laterally along the axis of the first field element core and protruding along the axis
Further comprising
The magnetic plate (5) has a hole (52) in the magnetic piece (50),
The hole locks the convex portion when the magnetic plate is in the first position and the first end (52c) that locks the convex portion when the magnetic plate is in the first position. The second end (52d) and a guide edge (52a, 52b) for guiding the circumferential movement of the convex portion in the hole between the first end and the second end are presented as an extension. 2. A field element (2) according to claim 4 or claim 4.   The field element (2) according to any one of claims 1 to 5, wherein the first field element core is located on a side opposite to the axis with respect to the permanent magnet.   The field element (2) according to claim 6, wherein the magnetic plate (5) further includes a non-magnetic material that connects the magnetic pieces (50) in a plane perpendicular to the axis (Q).   The field element (2) according to claim 6, wherein the magnetic plate (5) has a thickness different from other portions in a partial region (57) thereof.

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