JP2005198463A - Rotating electrical machine housing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce eddy current loss without lowering rotational torque and cost.
A housing 132 of a rotating electrical machine including a stator and a rotor is provided so as to face a slot, and a housing member that covers the stator and an eddy current corresponding to a magnetic flux generated by a current flowing through a coil of the slot. Includes openings 128 and 130 provided at portions formed by the housing member.
[Selection] Figure 5

Description

  The present invention relates to a structure of a rotating electric machine including a rotor and a stator, and more particularly to a structure of a housing.

  Conventionally, in a rotating electrical machine composed of a stator and a rotor, the stator is composed of a stator iron core in which a plurality of slots are formed, and a coil wound around a tooth provided between the slots. The rotor is composed of a rotor iron core, a magnet having a magnetic force, and a shaft serving as a rotation axis. A magnetic field is generated by supplying power to the coil. Based on the generated magnetic field, a flow of magnetic flux is formed between the rotor and the stator, so that the rotor obtains a rotational force. At this time, the magnetic flux not only flows to the stator and the rotor, but also flows to the outside as a leakage magnetic flux. For example, the leakage magnetic flux is generated in the direction parallel to the rotation axis of the rotating electrical machine from the teeth. Then, the leakage magnetic flux turns back and forms a flow to the adjacent teeth.

  At this time, an eddy current is generated in the housing covering the rotating electrical machine according to the leakage magnetic flux. Based on the eddy current generated in the housing, power loss due to the eddy current, so-called eddy current loss occurs. For such a problem, there is a technique disclosed in the following publications.

  Patent Document 1 (Japanese Patent Laid-Open No. 2001-251831) discloses a technique for reducing the generation of eddy current due to magnetic flux leaking from a rotor magnet in a brushless motor and suppressing the temperature rise of the brushless motor due to eddy current loss. This brushless motor includes a rotating body that includes a ring-shaped rotor magnet and is rotatably held around an axis, and a stator that is disposed with a magnet gap in a radial direction with respect to the rotor magnet. The rotor magnet has an open magnetic path at a portion other than the side facing the stator. And the magnetic body is arrange | positioned at the open magnetic path side of the rotor magnet.

According to Patent Document 1, the magnetic flux leaking from the rotor magnet is attracted to the magnetic material. And the magnetic flux which penetrates in the other fixed member arrange | positioned in the vicinity of the rotor magnet decreases. For this reason, the generation of eddy current is reduced in other fixing members in which the magnetic flux leaking from the rotor magnet is reduced. Eddy currents are generated in the magnetic body, but this magnetic body is arranged on the open magnetic path side and has a large distance from the rotor magnet. Therefore, the eddy current generated in the magnetic body is reduced. As a result, the generation of eddy currents in the entire brushless motor is reduced. In this way, the temperature rise of the brushless motor due to eddy current loss is suppressed.
JP 2001-251831 A

  In the brushless motor disclosed in Patent Document 1, a magnetic shield such as a magnetic body is attached to a housing of a rotating electrical machine. Therefore, since the magnetic flux leakage is attracted to the magnetic shield, the magnetic flux entering the housing can be reduced. However, in the magnetic shield, there is a problem in that the leakage flux itself increases because the magnetic resistance decreases. The increase in leakage flux causes a decrease in effective magnetic flux that contributes to the generation of rotational force (hereinafter referred to as rotational torque) of the rotating electrical machine. As a result, there has been a problem that the rotational torque of the rotating electrical machine is reduced. Further, since the magnetic shield is attached to the housing of the rotating electric machine, there is a problem that the number of parts increases, resulting in an increase in cost.

  The present invention has been made in order to solve the above-described problems, and an object of the present invention is to provide a housing for a rotating electrical machine that can reduce eddy current loss without reducing rotational torque and cost. Is to provide.

  A rotating electrical machine housing according to a first aspect of the present invention is a rotating electrical machine housing including a stator and a rotor. The stator has a slot around which the coil is wound. The housing includes a housing member that faces the slot and covers the stator, and an opening that is provided at a site where an eddy current corresponding to the magnetic flux generated by the current flowing through the coil is formed by the housing member. .

According to the first invention, the housing of the rotating electrical machine is formed with the housing member provided to face the slot and covering the stator, and an eddy current corresponding to the magnetic flux generated by the current flowing through the coil is formed by the housing member. By including the opening provided in the part, the eddy current can be effectively reduced without increasing the leakage magnetic flux. That is, the eddy current is generated according to the leakage magnetic flux from the teeth between the slots. At this time, the electromotive force generated by the leakage magnetic flux is represented by V (electromotive force) = − dφ (change in leakage magnetic flux) / dt (time) based on Lenz's law. The generated eddy current circulates in the housing of the rotating electrical machine to form an eddy current circuit. Therefore, for example, when an opening is provided at a portion corresponding to the eddy current path so as to divide the path of the eddy current circuit, the path of the eddy current circuit is divided by an insulator called air. This division is to increase the electrical resistance of the eddy current circuit. That is, the eddy current is represented by I (eddy current) = V / R (resistance) based on Ohm's law. Therefore, the eddy current decreases as the electrical resistance increases. The eddy current loss can be expressed by eddy current loss = I ² (eddy current) × R = V ² / R. Therefore, eddy current loss can be reduced as the electrical resistance increases. Further, since the magnetic resistance of the housing does not change, the leakage flux does not increase. Therefore, since the effective magnetic flux contributing to the torque generation is not reduced, the rotational torque does not decrease. Moreover, since the opening is provided in the housing, the number of parts is not increased. Therefore, an increase in cost can be suppressed. Therefore, it is possible to provide a housing for a rotating electrical machine that can reduce eddy current loss without lowering rotational torque and increasing costs.

  In the housing of the rotating electrical machine according to the second invention, in addition to the configuration of the first invention, the opening is formed by projecting the sectional shape of the slot onto the housing member in a direction parallel to the rotation axis. It is formed in the housing member so as to include the projected shape.

  According to the second invention, the opening is formed in the housing member so as to include a projected shape formed by projecting the cross-sectional shape of the slot onto the housing member. The eddy current loss generated according to the leakage magnetic flux becomes large at a portion on the slot of the stator. Therefore, the path of the eddy current circuit can be divided by an insulator called air by forming the opening so as to include the projected shape formed by projecting the cross-sectional shape of the slot. Therefore, the electrical resistance of the eddy current circuit can be increased. Therefore, eddy current can be reduced. That is, eddy current loss can be reduced.

  In the housing of the rotating electrical machine according to the third invention, in addition to the configuration of the second invention, the opening is formed in the housing member along the outer edge of the projected shape.

  According to the third aspect, by forming the opening in the housing member along the outer edge of the projected shape, the path of the eddy current circuit can be divided at a portion on the slot where the eddy current loss is high. As a result, since the electrical resistance of the eddy current circuit can be increased, the eddy current is reduced. Therefore, eddy current loss can be reduced.

  In the housing of the rotating electrical machine according to the fourth invention, in addition to the configuration of the first invention, the opening is a slit-like hole provided along the circumferential direction at a position corresponding to the slot of the housing member. .

  According to the fourth invention, since the eddy current flows in the radial direction, a slit-like hole is provided in the housing member along the circumferential direction provided at a position corresponding to the slot of the housing member (for example, the central portion of the slot). Thus, the eddy current path can be divided. And since the electrical resistance in an eddy current circuit can be increased with the insulator of the air on a path | route, an eddy current can be reduced. Therefore, eddy current loss can be reduced. Furthermore, the rigidity of the housing can be ensured as compared with the case where the opening is formed along the outer edge of the projected shape formed by projecting the sectional shape of the slot in a direction parallel to the rotation axis of the rotating electrical machine.

  In the rotating electrical machine housing according to the fifth aspect of the invention, in addition to the configuration of the fourth aspect of the invention, the position is shifted in the radial direction with respect to the slit-like hole provided at the position corresponding to the slot adjacent to the slot. It is the position.

  According to the fifth invention, the position where the slit-shaped hole is provided is the position shifted in the radial direction with respect to the slit-shaped hole provided at the position corresponding to the adjacent slot, thereby corresponding to the adjacent slot. A slit-like hole long in the circumferential direction can be provided in the housing member without overlapping with a slit-like hole provided at the position. Therefore, the rigidity of the housing can be ensured and the eddy current can be effectively reduced. Therefore, eddy current loss can be reduced.

  In the rotating electrical machine housing according to the sixth aspect of the invention, in addition to the configuration of the first aspect, the opening has a dimension that is longer in the direction perpendicular to the eddy current path than in the direction parallel to the path. These slit-shaped holes are formed in the housing member.

  According to the sixth aspect of the present invention, the housing member is provided with the slit-like hole whose dimension in the direction perpendicular to the path of the eddy current circuit is longer than the dimension in the direction parallel to the path. And eddy current can be reduced. That is, if the area of the opening is small, an eddy current flows along the opening, so that the path of the eddy current circuit cannot be divided. Therefore, in the slit-like hole, the eddy current path can be divided by setting the dimension in the direction orthogonal to the path to be longer than the dimension in the direction parallel to the path. And since the electrical resistance in an eddy current circuit can be increased with the insulator of the air on a path | route, an eddy current can be reduced. Therefore, eddy current loss can be reduced. Furthermore, the rigidity of the housing can be ensured as compared with the case where the opening is formed along the outer edge of the projected shape formed by projecting the sectional shape of the slot in a direction parallel to the rotation axis of the rotating electrical machine.

  In the housing of the rotating electrical machine according to the seventh invention, in addition to the structure of the sixth invention, the opening is formed by arranging a plurality of slit-shaped holes in the radial direction of the rotating electrical machine in the housing member. Is.

  According to the seventh invention, the opening is formed by slit-like holes arranged in a plurality (for example, three) in the radial direction of the rotating electrical machine. Thereby, the path | route of an eddy current circuit can be divided. And the electrical resistance in an eddy current circuit can be increased with the insulator called the air on a path | route. Therefore, eddy current can be reduced. Further, since the eddy current flows in the radial direction, the eddy current can be effectively reduced by arranging three slit-shaped holes in the housing member. Furthermore, the rigidity of the housing can be ensured as compared with the case where the opening is formed along the outer edge of the projected shape formed by projecting the sectional shape of the slot in a direction parallel to the rotation axis of the rotating electrical machine.

  In the rotary electric machine housing according to the eighth invention, in addition to the configuration of the sixth invention, the opening is formed by a slit-like hole along the radial direction starting from a position corresponding to the center of the magnetic flux of the housing. Is formed.

  According to the eighth aspect of the present invention, the path of the eddy current circuit is divided by providing a slit-like hole in the housing member along the radial direction starting from a position corresponding to the center of the magnetic flux of the housing as the opening. Can do. And the electrical resistance in an eddy current circuit can be increased with the insulator called the air on a path | route. Therefore, eddy current can be reduced. Furthermore, the rigidity of the housing can be ensured as compared with the case where the opening is formed along the outer edge of the projected shape formed by projecting the sectional shape of the slot in a direction parallel to the rotation axis of the rotating electrical machine.

  In the rotating electrical machine housing according to the ninth invention, in addition to the structure of any one of the first to seventh inventions, the opening is generated by the eddy current path and the current flowing in the coil of the slot adjacent to the slot. It is formed in the housing member so as to overlap the eddy current path corresponding to the magnetic flux to be generated.

  According to the ninth aspect, the opening is formed in the housing member so as to overlap the eddy current path and the eddy current path corresponding to the magnetic flux generated by the current flowing in the coil of the slot adjacent to the slot. By providing an opening so that two paths overlap each slot, one eddy current circuit can be divided at two locations. Therefore, the eddy current can be effectively reduced. Or the path | route of the two eddy current circuits which generate | occur | produce in two adjacent teeth can be divided | segmented by an at least 1 opening part. Therefore, eddy current can be reduced while ensuring the rigidity of the housing.

  A housing for a rotating electrical machine according to a tenth aspect of the invention is a housing for a rotating electrical machine including a stator and a rotor. The stator has a slot around which the coil is wound. The housing includes a housing member that faces the slot and covers the stator. The housing member is a non-magnetic material and is formed of a material having a high electrical resistivity.

  According to the tenth invention, the housing member is made of a non-magnetic material having a high electrical resistivity (for example, ceramics or resin), so that the housing member can be compared with the case where the opening is provided in the housing member. There is no reduction in rigidity. In addition, by using a material having a high electrical resistivity for the housing, since the electrical resistance is high, an eddy current is less likely to flow than a metal having a low electrical resistance such as an aluminum alloy generally used as a material for the housing. Therefore, eddy current can be reduced. Therefore, eddy current loss can be reduced. Further, since it is not necessary to provide an opening in the housing, the inside and outside of the motor can be separated. For example, it is effective when there is oil inside the motor and it should not leak outside.

  In the rotating electrical machine housing according to the eleventh invention, in addition to the structure of the tenth invention, the material is ceramics or resin.

  According to the eleventh invention, a metal having a low electrical resistance, such as an aluminum alloy, which is generally used as a material for a housing, is made of a ceramic or resin having a high electrical resistivity as a material for the housing member. As a result, the eddy current generated in the housing can be reduced. Furthermore, since it is not necessary to provide an opening, the rigidity of the housing does not decrease.

  Hereinafter, a housing for a rotating electrical machine according to an embodiment of the present invention will be described with reference to the drawings. In the following description, the same parts are denoted by the same reference numerals. Their names and functions are also the same. Therefore, detailed description thereof will not be repeated.

<First Embodiment>
First, the structure of the rotating electrical machine will be described before the housing of the rotating electrical machine according to the present embodiment is described in detail.

  As shown in FIG. 1, the rotating electrical machine 150 includes a rotor composed of a rotor core 102, an end plate 104, and a shaft 106, and a stator composed of a stator core 108 and a coil (not shown). FIG. 1 shows one of the four divided in the circumferential direction of the rotating electrical machine 150.

  The stator core 108 has a hollow cylindrical shape. The stator core 108 has a plurality of slots 112 and 114 in a direction parallel to the rotation axis of the rotating electrical machine 150. A tooth 110 is formed between the slots 112 and 114. A coil (not shown) is wound around the teeth 110. The hollow portion of the stator core 108 has a cylindrical rotor. The rotor includes a rotor core 102 formed by embedding a permanent magnet having magnetic force, an end plate 104 provided on an end surface of the rotor core 102, the rotor core 102 and the end plate 104, and a shaft serving as a rotation axis. 106.

  As shown in FIG. 2, the rotary electric machine 150 is provided with a housing 100 that covers the stator so as to face the slots 112 and 114. The housing 100 is provided for the purpose of fixing the bearing of the rotor shaft 106 and the stator. That is, the housing 100 is fixed to the stator. A bearing portion of the rotor shaft 106 is provided in the housing 100. By assembling the rotor, the rotor and the stator can maintain a predetermined positional relationship. The material of the housing 100 is generally an aluminum alloy such as Al-12Si, but is not particularly limited.

  Here, when electric power is supplied to the coil 116 wound around the teeth shown in FIG. 2, a magnetic flux is generated in the coil 116 in accordance with the flow of current. The magnetic flux generated in the coil 116 forms a magnetic flux flow between the stator and the rotor. In accordance with the flow of the magnetic flux, the rotor obtains a rotational force (hereinafter referred to as rotational torque). At this time, the magnetic flux generated in the coil 116 flows not only to the stator and the rotor but also to the outside as a leakage magnetic flux. For example, the leakage magnetic flux is generated from the tooth 110 around which the coil 116 is wound in a direction parallel to the rotation axis of the rotating electrical machine 150. The leakage magnetic flux generated in the direction parallel to the rotation axis is folded back to form a flow to the teeth adjacent to the teeth 110. And the eddy current which is an induced current arises in the housing 100 by the leakage magnetic flux which arose from the teeth 110, and the leakage magnetic flux which flows into the adjacent teeth. The eddy current flows in a direction based on the right-handed screw law depending on the direction of the leakage magnetic flux. At this time, as shown in FIG. 3, eddy current circuits 118, 120, and 122 that form a eddy current path are formed by circulating to the housing 100 due to the leakage magnetic flux. In the formed eddy current circuits 118, 120, and 122, power loss due to eddy current, so-called eddy current loss, occurs based on the eddy current. The power lost in the housing 100 is finally converted into thermal energy. The eddy current loss generated based on such eddy current tends to be large at a place where the density of eddy current is high. As shown in FIG. 3, eddy currents flow in the same direction in the eddy current circuits 118, 120, and 122. Therefore, as shown in FIG. 4, the eddy current density is high in the eddy current loss portions 124 and 126 on the slot (dotted line in FIG. 4). Therefore, the eddy current loss in the eddy current loss parts 124 and 126 is large.

  Therefore, the housing of the rotating electrical machine according to the present embodiment has an opening at a portion corresponding to the path of the eddy current corresponding to the magnetic flux generated by the current flowing through the coil of the slot. Specifically, the opening is formed in the housing so as to include a projected shape formed by projecting the sectional shape of the slot onto the housing in a direction parallel to the rotation axis of the rotating electrical machine. Here, the shape of the opening is not particularly limited, but in the present embodiment, for example, the opening is formed in the housing along the outer edge of the projected shape.

  As shown in FIG. 5, the housing 132 is projected onto the housing 132 in a direction parallel to the rotation axis in a plane perpendicular to the rotation axis of the plurality of slots 112, 114 of the stator core 108. Openings 128 and 130 are provided in the housing 132 along the outer edge of the projected shape. Although the manufacturing method of the housing 132 provided with the opening parts 128 and 130 is not specifically limited, For example, it forms by press molding.

As described above, according to the housing of the rotating electrical machine according to the first embodiment, the housing of the rotating electrical machine is generated by the housing member that is provided to face the slot and covers the stator, and the current flowing through the coil. By including an opening provided in a portion where the eddy current corresponding to the magnetic flux is formed by the housing member, the eddy current can be effectively reduced without increasing the leakage magnetic flux. That is, the eddy current is generated according to the leakage magnetic flux from the teeth between the slots. At this time, the electromotive force generated by the leakage magnetic flux is represented by V (electromotive force) = − dφ (change in leakage magnetic flux) / dt (time) based on Lenz's law. The generated eddy current circulates in the housing of the rotating electrical machine to form an eddy current circuit. Therefore, for example, when an opening is provided at a portion corresponding to the eddy current path so as to divide the path of the eddy current circuit, the path of the eddy current circuit is divided by an insulator called air. This division is to increase the electrical resistance of the eddy current circuit. That is, the eddy current is represented by I (eddy current) = V / R (resistance) based on Ohm's law. Therefore, the eddy current decreases as the electrical resistance increases. The eddy current loss can be expressed by eddy current loss = I ² (eddy current) × R = V ² / R. Therefore, eddy current loss can be reduced as the electrical resistance increases. Further, since the magnetic resistance of the housing does not change, the leakage flux does not increase. Therefore, since the effective magnetic flux contributing to torque generation is not reduced, the rotational torque does not decrease. Moreover, since the opening is provided in the housing, the number of parts is not increased. Therefore, an increase in cost can be suppressed. Therefore, it is possible to provide a housing for a rotating electrical machine that can reduce eddy current loss without lowering rotational torque and increasing costs.

  The opening is formed in the housing so as to include a projected shape formed by projecting the cross-sectional shape of the slot onto the housing in a direction parallel to the rotation axis of the rotating electrical machine. The eddy current loss generated according to the leakage magnetic flux becomes large at a portion on the slot of the stator. Therefore, by forming an opening in the housing along the outer edge of the projected shape formed by projecting the cross-sectional shape of the slot, the path of the eddy current circuit can be divided by an insulator called air. Therefore, the electrical resistance of the eddy current circuit can be increased. Therefore, eddy current can be reduced.

  Also, the opening is formed in the housing so that the eddy current path and the eddy current path corresponding to the magnetic flux generated by the current flowing in the coil of the slot adjacent to the slot overlap. By providing an opening so that two paths overlap each slot, one eddy current circuit can be divided at two locations. Therefore, the eddy current can be effectively reduced. Or the path | route of the two eddy current circuits which generate | occur | produce in two adjacent teeth can be divided | segmented by an at least 1 opening part. Therefore, eddy current can be reduced while ensuring the rigidity of the housing.

<Second Embodiment>
Hereinafter, the housing of the rotating electrical machine according to the second embodiment of the present invention will be described.

  The rotating electrical machine according to the present embodiment has the same configuration as the rotating electrical machine 150 according to the first embodiment except for the housing 132. They are given the same reference numerals. Their functions are the same. Therefore, detailed description thereof will not be repeated here.

  The rotary electric machine housing 200 according to the second embodiment is provided with a plurality of slit-shaped holes arranged in the radial direction of the rotary electric machine 150 so as to overlap the paths of the eddy current circuits 208 and 210. The number of slits is not particularly limited. For example, in the present embodiment, three slit-shaped holes 202, 204, and 206 are provided in the housing 200 in the radial direction. Further, it is assumed that three slit-shaped holes as shown in FIG. 6 are provided in all overlapping portions of the eddy current circuit path on the circumference of the housing 200. In this way, the eddy current can be reduced by dividing the path of the eddy current circuits 208 and 210.

  At this time, the slit-shaped holes 202, 204, and 206 have dimensions that are longer in the direction perpendicular to the path of the eddy current circuits 208 and 210 than in the direction parallel to the path. In the present embodiment, the slit-shaped holes 202, 204, 206 are longer in the direction perpendicular to the radial direction of the rotating electrical machine than the length in the direction perpendicular to the path of the eddy current circuit of the eddy current loss portion 212. And

  As described above, according to the housing of the rotating electrical machine according to the second embodiment, the slit-like dimension in which the dimension in the direction perpendicular to the eddy current path as the opening is longer than the dimension in the direction parallel to the path. By providing the hole in the housing, the rigidity of the housing can be ensured and the eddy current can be reduced. That is, if the area of the opening is small, an eddy current flows along the opening, so that the path of the eddy current circuit cannot be divided. Therefore, in the slit-like hole, the eddy current path can be divided by setting the dimension in the direction orthogonal to the path to be longer than the dimension in the direction parallel to the path. And since the electrical resistance in an eddy current circuit can be increased by the insulation part called air on a path | route, an eddy current can be reduced. Therefore, eddy current loss can be reduced. Furthermore, the rigidity of the housing can be ensured as compared with the case where the opening is formed along the outer edge of the projected shape formed by projecting the sectional shape of the slot in a direction parallel to the rotation axis of the rotating electrical machine.

  The opening is formed by three slit-shaped holes arranged in the radial direction of the rotating electrical machine. Thereby, the path | route of an eddy current circuit can be divided.

  The opening is formed in the housing so that the eddy current path and the eddy current path corresponding to the magnetic flux generated by the current flowing in the coil of the slot adjacent to the slot overlap. By providing an opening so that two paths overlap each slot, one eddy current circuit can be divided at two locations. Therefore, the eddy current can be effectively reduced. Or the path | route of the two eddy current circuits which generate | occur | produce in two adjacent teeth can be divided | segmented by an at least 1 opening part. Therefore, eddy current can be reduced while ensuring the rigidity of the housing.

<Modification of Second Embodiment>
A rotating electrical machine housing according to a modification of the second embodiment of the present invention will be described below.

  The rotating electrical machine according to this modification has the same configuration as that of the rotating electrical machine 150 according to the second embodiment described above, except for the housing 200. They are given the same reference numerals. Their functions are the same. Therefore, detailed description thereof will not be repeated here.

  In the housing 300 of the rotating electrical machine according to the present modification, slit-like holes are provided at positions corresponding to the slots or the teeth between the slots on the path of the eddy current circuit.

  Specifically, for example, as shown in FIG. 7, the path of the eddy current circuit 302 generated in the housing 300 and the path of the eddy current circuit formed based on the magnetic flux from the adjacent teeth overlap. A slit-shaped hole 304 is provided along the circumferential direction at a position corresponding to the center of the slot of the housing 300. Then, a hole having the same shape as the slit-like hole 304 is provided at each position corresponding to every slot on the circumference of the housing 300. Since the eddy current flows in the radial direction, the path of the eddy current can be divided by providing a slit-like hole in the housing along the circumferential direction.

  Further, if a long slit-like hole is provided along the circumferential direction, it overlaps with a slit-like hole corresponding to an adjacent slot, and the housing cannot be realized. Alternatively, the rigidity of the housing may not be ensured. Therefore, as shown in FIG. 8, the slit-shaped holes 312 are alternately arranged in the radial direction by shifting the holes on the slits long in the circumferential direction from the slit-shaped holes provided at positions corresponding to the adjacent slots. May be. By providing a longer slit-like hole in the circumferential direction, the path of eddy current can be effectively divided. At this time, the rigidity of the housing can be ensured by disposing the slit-like holes alternately in the circumferential direction while shifting in the radial direction.

  Alternatively, the slit-shaped hole is provided in the housing 300 as shown in FIG. 9 starting from a position corresponding to the center of the leakage magnetic flux of the housing 300. For example, as shown in FIG. 9A, the slit-shaped hole 306 rotates inward from the center of the leakage magnetic flux passing through the housing 300 from the center of the tooth on the path of the eddy current circuit 302 with respect to the housing 300. It is provided along the radial direction of the electric machine 150. At this time, the shape of the slit-shaped hole is such that the dimension in the direction perpendicular to the path of the eddy current circuit is longer than the dimension in the direction parallel to the path. Then, a hole having the same shape as the slit-shaped hole 306 may be provided at a position corresponding to the center of the leakage magnetic flux passing through the housing 300.

  Alternatively, as shown in FIG. 9B, the slit-shaped hole 308 has a diameter outside the center of the leakage magnetic flux that penetrates the housing 300 from the center of the tooth on the path of the eddy current circuit 302 with respect to the housing 300. You may provide along a direction.

  Alternatively, as shown in FIG. 9C, the slit-shaped hole 310 has a leakage magnetic flux penetrating through the housing 300 from the center of the tooth so as to divide the eddy current circuit 310 at two locations with respect to the housing 300. You may provide along radial direction based on a center.

  As described above, according to the housing of the rotating electric machine according to this modification, the rigidity of the housing is ensured by providing the slit-like holes at positions corresponding to the respective teeth or slots on the path of the eddy current circuit. In addition, eddy current can be reduced. Therefore, eddy current loss can be reduced.

<Third Embodiment>
Hereinafter, the housing of the rotating electrical machine according to the third embodiment of the present invention will be described.

  The rotating electrical machine according to the present embodiment has the same configuration as the rotating electrical machine 150 according to the first embodiment except for the housing 132. They are given the same reference numerals. Their functions are the same. Therefore, detailed description thereof will not be repeated here.

  The housing of the rotating electrical machine according to the third embodiment is made of a material that is non-magnetic and has a high electrical resistivity. Thereby, compared with the case where an opening part is provided in a housing, there is no rigidity fall of a housing. In addition, by using a material having a high electrical resistivity for the housing, since the electrical resistance is high, an eddy current is less likely to flow than a metal having a low electrical resistance such as an aluminum alloy generally used as a material for the housing. Therefore, eddy current can be reduced. Further, since there is no need to provide an opening in the housing, the inside of the motor and the outside can be partitioned. For example, it is effective when there is oil inside the motor and it should not leak outside. The material of the housing is not particularly limited as long as it is a non-magnetic material and has high electrical and low efficiency. For example, it is ceramic or resin.

  As described above, according to the rotating electrical machine housing according to the third embodiment, the material of the rotating electrical machine housing is a non-magnetic material such as ceramics or resin, and has a high electrical resistivity. By using the material, the eddy current generated in the housing can be reduced. Therefore, eddy current loss can be reduced without reducing the rigidity of the housing.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

It is a figure which shows the external appearance of a rotary electric machine. It is a figure which shows the external appearance of the housing attached to the rotary electric machine. It is a figure which shows the path | route of the eddy current circuit formed in the housing of the rotary electric machine which concerns on 1st Embodiment. It is a figure which shows a site | part with a large eddy current loss formed in the housing of the rotary electric machine which concerns on 1st Embodiment. It is a figure which shows the external appearance of the housing of the rotary electric machine which concerns on 1st Embodiment. It is a figure which shows the external appearance of the housing of the rotary electric machine which concerns on 2nd Embodiment. It is a front view (the 1) of the housing of the rotation electrical machinery concerning the modification of a 2nd embodiment. It is a front view (the 2) of the housing of the rotary electric machine which concerns on the modification of 2nd Embodiment. It is a front view (the 3) of the housing of the rotary electric machine which concerns on the modification of 2nd Embodiment.

Explanation of symbols

  100, 132, 200, 300 housing, 102 rotor core, 104 end plate, 106 shaft, 108 stator core, 110 teeth, 112, 114 slot, 116 coil, 118, 120, 122, 208, 210, 302 eddy current circuit, 124, 126, 212 Eddy current loss part, 128, 130 opening part, 150 rotating electrical machine, 202, 204, 206, 304, 306, 308, 310, 312 Slit-like holes.

Claims (11)

A rotating electrical machine housing comprising a stator and a rotor, the stator having a slot around which a coil is wound,
The housing is
A housing member that is provided opposite to the slot and covers the stator;
A housing for a rotating electrical machine, comprising: an opening provided in a portion where an eddy current corresponding to a magnetic flux generated by a current flowing through the coil is formed by the housing member.   The housing of a rotating electrical machine according to claim 1, wherein the opening is formed in the housing member so as to include a projected shape formed by projecting a cross-sectional shape of the slot onto the housing member.   The rotating electrical machine housing according to claim 2, wherein the opening is formed in the housing member along an outer edge of the projected shape.   The rotating electrical machine housing according to claim 1, wherein the opening is a slit-shaped hole provided along a circumferential direction at a position corresponding to the slot of the housing member.   5. The rotating electrical machine housing according to claim 4, wherein the position is a position shifted in a radial direction with respect to a slit-like hole provided at a position corresponding to a slot adjacent to the slot.   2. The opening according to claim 1, wherein the opening is formed by providing a slit-like hole in the housing member whose dimension in a direction orthogonal to the path of the eddy current is longer than a dimension in a direction parallel to the path. The housing of the rotating electric machine described.   The housing of a rotating electrical machine according to claim 6, wherein the opening is formed in the slit-like holes arranged in a plurality in the radial direction of the rotating electrical machine.   The housing of a rotating electrical machine according to claim 6, wherein the opening is formed by the slit-shaped hole along a radial direction starting from a position corresponding to the center of the magnetic flux of the housing.   The opening is formed in the housing member so as to overlap a path of the eddy current and a path of eddy current corresponding to a magnetic flux generated by a current flowing in a coil of a slot adjacent to the slot. The housing | casing of the rotary electric machine in any one of 1-7. A rotating electrical machine housing comprising a stator and a rotor, the stator having a slot around which a coil is wound,
The housing is
A housing member provided to face the slot and covering the stator;
The housing member is a non-magnetic material, and is formed of a material having a high electrical resistivity.   The housing for a rotating electrical machine according to claim 10, wherein the material is ceramic or resin.

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