JP3347939B2 - Permanent magnet rotor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a permanent magnet for a rotating electric machine constituted by arranging a plurality of rare earth permanent magnets such as a neodymium-iron-boron magnet or a praseodymium magnet around a rotor shaft. The present invention relates to a rotor, and more particularly to a structure for fixing a permanent magnet.

[0002]

2. Description of the Related Art A permanent magnet fixing structure of a conventional permanent magnet rotor of this type is not shown, but is arranged on a rotor shaft as shown in, for example, Japanese Patent Application Laid-Open No. 61-39838. A structure in which the perimeter of the permanent magnet is fastened with a glass cloth impregnated with a resin and then fixed by curing the impregnated resin, or as shown in JP-A-58-195460, on the rotor shaft. A structure in which a permanent magnet is adhered and arranged, and a thin metal strip is wound around the permanent magnet to fix the permanent magnet.
As shown in Japanese Patent No. 543, a permanent magnet is bonded and arranged on a rotor shaft, a thin cylinder is fitted around the permanent magnet, and the thin cylinder is fixed by plastic deformation along the outer shape of the permanent magnet. And the like are proposed.

[0003]

Generally, permanent magnets are hard and brittle because rare-earth permanent magnets are used, and have a thermal expansion coefficient of an iron-based material that forms the rotor shaft. Is different. Incidentally, the thermal expansion coefficient of the iron-based material is 11 × 1
0 ^-6 / a is whereas ° C., neodymium - iron - thermal expansion coefficient of the boron-based magnet 0.7 × 10 ^-6 / ° C., the thermal expansion coefficient of praseodymium based magnet 2 to 3 × 10 ^-6 / ° C. It is. Therefore, when the permanent magnet is fixed by bonding, there is a problem that the deterioration of the adhesive or the growth of cracks due to the temperature change of the rotating electric machine shortens the life of the rotor and lowers the reliability. .

[0004] In addition, since the layer in which the adhesive is interposed obstructs the magnetic path, the performance of the rotating electric machine is reduced as compared with the case where the permanent magnet is in direct contact with, for example, the surface of the rotor shaft. In addition, when reinforcing members such as glass cloth, metal strip, and thin-walled cylinder are used as described above to supplement the adhesive force, these reinforcing members are interposed between the rotor and the stator. Therefore, there is a problem that the provision of an extra gap is equivalent to the provision of an extra gap, and the performance of the rotating electric machine is reduced.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems. An adhesive layer is provided at a position where a magnetic path is obstructed, and a reinforcing member is interposed between a rotor and a stator. It is an object of the present invention to provide a permanent magnet rotor capable of preventing a decrease in reliability and performance by adopting a configuration that does not perform such a process.

[0006]

According to a first aspect of the present invention, there is provided a permanent magnet rotor including a rotor shaft having a step formed with a large diameter at a part in an axial direction, and a stepped outer peripheral surface. It is arranged at a certain pitch in the circumferential direction and has the same length in the axial direction as the step.
A plurality of permanent magnets each having a shape, and a plurality of projecting connection portions that are elastically deformable in the axial and circumferential directions are formed at positions that are annular and abut against end faces of the respective permanent magnets on the outer peripheral portion.
And a pair of magnetic poles whose inner peripheral portion is in contact with the end face of the step.
A stone fixing plate is provided, and the inner peripheral portion of the magnet fixing plate is
In addition, each connecting part of the outer peripheral part
By welding or bonding to the end face,
The magnet is fixed to the rotor shaft .

According to a second aspect of the present invention, there is provided a permanent magnet rotor, comprising: a rotor shaft; a cylindrical member fitted to the rotor shaft and disposed at a predetermined position in the axial direction; A cylinder arranged on the outer peripheral surface of the member at a predetermined pitch in the circumferential direction
A plurality of permanent magnets having the same length dimension in the axial direction as the shape-like member, and a plurality of protrusion-like elastically deformable axially and circumferentially at a position in contact with an end face of each of the permanent magnets on the outer peripheral portion in an annular shape.
Each connecting part is formed, and the inner peripheral part is cylindrical
A pair of magnet fixing plates abutting on the end surface of the shaped member,
The inner peripheral part of the magnet fixing plate is attached to the end face of the cylindrical member,
Connect each connecting part to the end face of the corresponding permanent magnet
By welding or bonding, each permanent magnet is
It is designed to be fixed to the material .

According to a third aspect of the present invention, there is provided a permanent magnet rotor according to the second aspect, wherein a plurality of cylindrical members are provided.

According to a fourth aspect of the present invention, there is provided the permanent magnet rotor according to the third aspect, wherein each cylindrical member is rotated such that the positions of the permanent magnets are sequentially shifted by a predetermined angle in the circumferential direction. It is fitted to.

According to a fifth aspect of the present invention, there is provided a permanent magnet rotor according to any one of the first to fourth aspects, wherein the magnet fixing plate is connected to the same number of segment pieces as the permanent magnets, and these segment pieces are connected to each other. And a thin member.

A permanent magnet rotor according to a sixth aspect of the present invention is the permanent magnet rotor according to the second aspect, wherein the cylindrical member is constituted by a plurality of plate members laminated in the axial direction.

According to a seventh aspect of the present invention, there is provided a permanent magnet rotor according to the sixth aspect, wherein the plate-like member is composed of the same number of segment pieces as the permanent magnets connected to each other on the outer peripheral side. Are formed in a cylindrical shape by abutting their side ends.

According to an eighth aspect of the present invention, in the permanent magnet rotor according to the sixth or seventh aspect, each of the plate-shaped members located at both ends of the cylindrical member also serves as a magnet fixing plate. .

According to a ninth aspect of the present invention, there is provided a permanent magnet rotor according to any one of the first to eighth aspects, wherein the connecting portion is formed in a comb-like shape.

According to a tenth aspect of the present invention, there is provided a permanent magnet rotor according to any one of the first to eighth aspects, wherein the connecting portion is formed in a plurality of projections having a crack that does not break. is there.

A permanent magnet rotor according to claim 11 of the present invention has a plurality of plate-like members each having a rotor shaft and a crack which is fitted to the rotor shaft and which is not broken near the outer peripheral portion. A cylindrical member formed by laminating members, and fixed at a predetermined pitch in a circumferential direction of an outer peripheral surface of the cylindrical member,
And a plurality of permanent magnets to be arranged.

According to a twelfth aspect of the present invention, there is provided a permanent magnet rotor according to the eleventh aspect, wherein a crack that does not break is formed along a desired magnetic circuit.

According to a thirteenth aspect of the present invention, there is provided a permanent magnet rotor according to any one of the first to twelfth aspects, wherein the permanent magnet is fixed by energy beam welding, and the pulse feed pitch of the energy beam welding is energy beam welding. The diameter is set in a range of 1 to 1.5 times the diameter of a weld bead formed by welding.

A permanent magnet rotor according to a fourteenth aspect of the present invention is the permanent magnet rotor according to any one of the first to thirteenth aspects, wherein a rare earth permanent magnet such as a neodymium-iron-boron magnet or a praseodymium magnet is used as the permanent magnet. In this method, a permanent magnet is fixed by energy beam welding, and a member fixed to the permanent magnet is subjected to a boring treatment, boron diffusion plating, or nickel-boron plating.

A permanent magnet rotor according to a fifteenth aspect of the present invention is the permanent magnet rotor according to any one of the first to thirteenth aspects, wherein a rare earth permanent magnet such as a neodymium-iron-boron magnet or a praseodymium magnet is used as the permanent magnet. In the method, a permanent magnet is fixed by energy beam welding, and a member fixed to the permanent magnet is formed of a material containing a boron additive.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiment 1 FIG. FIG. 1 is a diagram showing a configuration of a permanent magnet rotor according to Embodiment 1 of the present invention, where (A) is a front view,
(B) is a side sectional view. FIG. 2 is a front view showing a configuration of a main part of the permanent magnet rotor in FIG. In the figure,
Reference numeral 1 denotes a rotor shaft having a step portion 1a having a large diameter formed at the center portion, and 2 is disposed on the outer peripheral surface of the step portion 1a of the rotor shaft 1 at a predetermined pitch in a circumferential direction. A plurality of permanent magnets made of a rare earth element such as a neodymium-iron-boron-based magnet or a praseodymium-based magnet.
It is formed in the same size as the length of a.

Reference numeral 3 denotes a pair of annular magnet fixing plates disposed so as to be in contact with the stepped portion 1a of the rotor shaft 1 and both end surfaces of the permanent magnets 2, respectively. A protruding connection portion 3a provided with a small crack that does not lead to breakage is formed at the position where the break occurs. And
These magnet fixing plates 3 and 3 have inner peripheral portions on the end face of the stepped portion 1a by welding, and outer peripheral portions of the respective permanent magnets 2 by laser welding via the connecting portion 3a as shown in FIG. Each permanent magnet 2 is fixed to the rotor shaft 1 by being fixed to the end face.

Next, the connecting portion 3a of the magnet fixing plate 3 of the magnet rotor according to the first embodiment configured as described above.
Next, a method for forming a minute crack that does not lead to fracture will be described with reference to FIG. First, an upper mold 4 having a number of projections 4a protruding by a dimension h at a predetermined position on the lower surface, and each of the projections being disposed below the upper mold 4 and corresponding to each of the projections 4a of the upper mold 4, respectively. A plate member 7 serving as the magnet fixing plate 3 is inserted between a first press die 6 including a lower die 5 having a concave portion 5a that can be fitted with the lower die 4a.

Next, the upper mold 4 is lowered and the lower surface is moved to the lower mold 5.
When the upper mold 4 is lifted and returned to its original position after being brought into contact with the upper surface of the, a half blanked portion 8 is formed as shown in the figure. Next, a second die including an upper die 9 having a flat lower surface and a lower die 10 having a flat upper surface is provided.
When the plate member 7 is inserted between the press dies 11 and the upper die 9 is lowered, the lower surface is brought into contact with the upper surface of the lower die 10, and then the upper die 9 is raised and returned to its original state. As shown schematically in FIG. 1, a minute crack 12 that does not break is formed.

As described above, according to the first embodiment, the connecting portion 3 fixed to the end surface of the permanent magnet 2 of the magnet fixing plate 3
a is formed by a plurality of projections provided with cracks that do not break, and the strength is locally weakened, so that the permanent magnet 2 and the magnet fixing plate 3 having different thermal expansion coefficients due to the temperature change of the rotating electric machine. Even if is expanded or contracted, the connecting portion 3a is elastically deformed in the axial and circumferential directions to absorb the difference in the amount of expansion and contraction,
Since good joining is achieved without excessive stress concentrated on the joining surface between the permanent magnet 2 and the magnet fixing plate 3, the life of the rotor is extended and the reliability is improved.

A magnet fixing plate 3 is provided on the end face side of the permanent magnet 2.
Since there is nothing between the rotor and the stator, there is no need to provide an extra gap, and the permanent magnet 2 and the outer peripheral surface of the rotor shaft 1 The direct contact eliminates the need for an adhesive layer or the like that hinders the magnetic path, thereby improving the performance of the rotating electric machine.

The magnet fixing plate 3 shown in FIG. 1 is elastically deformable in the axial and circumferential directions by forming the connecting portion 3a into a plurality of protrusions provided with cracks that do not break. As shown in FIG. 5, a position facing the end face of each permanent magnet 2 on the outer peripheral portion of the magnet fixing plate 13 is processed into a comb-like shape to form a connection portion 13a, and the laser is transmitted through the connection portion 13a. It may be fixed to the end face of the permanent magnet 2 by welding. The connecting portion 13a has a comb-teeth shape, the strength of which is locally weakened, and is elastically deformable in the axial and circumferential directions. Can be obtained.

Embodiment 2 FIG. 6 is a diagram showing a configuration of a permanent magnet rotor according to Embodiment 2 of the present invention.
7B is a front view, FIG. 7B is a side cross-sectional view, FIGS. 7 and 8 are views showing an assembling process of a main part of the permanent magnet rotor in FIG. 6, respectively, and FIG. It is a front view which shows a structure. In the figure, 14 is a rotor shaft, 15
Are two cylindrical members fitted to the rotor shaft 14, respectively, and 16 is, for example, neodymium-iron-iron disposed on the outer peripheral surface of each cylindrical member 15 at a predetermined pitch in the circumferential direction. A plurality of permanent magnets made of a rare earth element such as a boron-based magnet or a praseodymium-based magnet;
5 and a plurality of magnet fixing plates disposed so as to abut on both end surfaces of the permanent magnet 16, and a comb-shaped connecting portion 17 a at a position facing the end surface of each permanent magnet 16 on the outer peripheral portion. Is provided.

Next, a method of assembling the permanent magnet rotor according to the second embodiment configured as described above will be described. First, as shown in FIG. 7, a pair of magnet fixing plates 17 are fixed to both ends of each cylindrical member 15 by welding. Next, as shown in FIG. 8, the permanent magnet 16 is interposed between the connecting portions 17 a of the two magnet fixing plates 17 so as to abut against the outer peripheral surface of the cylindrical member 15, and as shown in FIG. The permanent magnet 16 is fixed on the outer periphery of the cylindrical member 15 by laser welding the connection portions 17 a of the magnet fixing plate 17. Finally, each unit assembled as described above is fixed at a predetermined position on the rotor shaft 14 to obtain a permanent magnet rotor.

As described above, according to the second embodiment, the cylindrical member 15 is fitted to the rotor shaft 14 and integrated therewith, so that the step as in the first embodiment is placed on the rotor shaft 14. There is no need to separately provide the portion, and the cost can be significantly reduced as compared with the case where the step portion is formed by being cut out from a large-diameter material. Also, magnet fixing plate 1
7 is connected to the end face of the permanent magnet 16
Are formed in the shape of a comb, and the strength is locally weakened, so that the permanent magnet 16 and the magnet fixing plate, each having a different thermal expansion coefficient due to a change in the temperature of the rotating electric machine, as in the first embodiment. Even if the member 17 expands or contracts, the connecting portion 17a elastically deforms in the axial and circumferential directions to absorb the difference in the amount of expansion and contraction, so that excessive stress concentrates on the joint surface between the permanent magnet 16 and the magnet fixing plate 17. As a result, good bonding is achieved, so that the life of the rotor is prolonged and the reliability is improved.

Further, since the magnet fixing plate 17 is disposed on the end face side of the permanent magnet 16, there is no intervening member between the rotor and the stator, so that there is no need to provide an extra gap. , And the permanent magnet 16 and the rotor shaft 1
4 is in direct contact with the outer peripheral surface, so that there is no intervening adhesive layer or the like that hinders the magnetic path, so that the performance of the rotating electric machine can be improved.

The magnet fixing plate 17 shown in FIG. 6 can be elastically deformed in the axial and circumferential directions by making the connecting portion 17a comb-shaped. As shown, it is needless to say that the same effect can be exerted even when the connecting portion is formed as a plurality of protrusions provided with cracks that do not break.

In the configuration of the permanent magnet rotor shown in FIG. 6, the positions of the permanent magnets 16 arranged on the respective cylindrical members 15 are arranged so as to be aligned in the axial direction.
As shown in FIG. 0, each of the cylindrical members 15 is sequentially shifted by the aforementioned angle so that the position of the permanent magnet 16 disposed on each of the cylindrical members 15 is sequentially shifted by a predetermined angle in the circumferential direction. If the rotor is fitted and fixed, the same effect as when the rotor is provided with skew can be obtained, and cogging torque, torque ripple, rotation unevenness, and the like can be reduced.

Embodiment 3 FIG. 11 is a diagram showing a configuration of a permanent magnet rotor according to Embodiment 3 of the present invention.
(A) is a front view, (B) is a side sectional view, FIG. 12 and FIG.
3 is a diagram showing an assembling process of a main part of the permanent magnet rotor in FIG. 11; In the figure, a rotor shaft 14, a cylindrical member 15, and a permanent magnet 16 are the same as those in the second embodiment shown in FIG. Reference numeral 18 denotes the same number of segment pieces 18a as the number of the permanent magnets 16 arranged on the outer periphery of the cylindrical member 15, a thin member 18b connecting these segment pieces 18a, and an end face of the permanent magnet 16 of each segment piece 18a. And a connecting portion 18c formed in a comb-like shape at a position where the magnet is fixed.

Next, a method of assembling the permanent magnet rotor according to the third embodiment configured as described above will be described. First, the magnet fixing plates 1 arranged in two rows as shown in FIG.
The permanent magnets 16 are inserted between the segments 8 and 18 at the same pitch as the segment pieces 18a, and the connecting portions 18c of the two magnet fixing plates 18 and 18 are laser-welded to both end surfaces of the permanent magnets 16 so that each permanent magnet 16 16 is fixed between both magnet fixing plates 18, 18. Next, as shown in FIG.
While sequentially deforming b, it is wound around the outer periphery of the cylindrical member 15 and each segment piece 18a is welded to the end face of the cylindrical member 15 to constitute one unit.
Finally, each unit assembled as described above is fixed at a predetermined position on the rotor shaft 14 to obtain a permanent magnet rotor.

As described above, according to the third embodiment, each permanent magnet 16 is inserted and fixed between the pair of band-shaped magnet fixing plates 18, 18, and each thin member of the magnet fixing plate 18 is fixed. Since the unit is formed by winding around the outer peripheral surface of the cylindrical member 15 while sequentially deforming the 18b, the workability of assembly is greatly improved. Also, magnet fixing plate 1
8 and the permanent magnet 16 can be arranged on a straight line, so that the permanent magnet 1
6 can be easily improved in comparison with the case of arranging and joining one by one, and when configured as a rotating electric machine, a high-precision rotor can be obtained, and consequently, cogging torque and torque. It is possible to reduce ripples and uneven rotation.

The magnet fixing plate 18 shown in FIG. 11 can be elastically deformed in the axial and circumferential directions by making the connecting portion 18c comb-shaped. As shown, it is needless to say that the same effect can be exerted even when the connecting portion is formed as a plurality of protrusions provided with cracks that do not break.

Embodiment 4 FIG. FIG. 14 is a diagram showing a configuration of a permanent magnet rotor according to Embodiment 4 of the present invention.
FIG. 15A is a front view, FIG. 15B is a side sectional view, and FIG. 15 is a view showing an assembling process of a main part of the permanent magnet rotor in FIG. In the figure, rotor shaft 14 and permanent magnet 16 are the same as those in the third embodiment shown in FIG. Reference numeral 19 denotes a cylindrical member composed of a plurality of plate members laminated in the axial direction. Reference numeral 20 denotes a cylindrical member that is laminated on both ends of the cylindrical member 19 together with the plate members, fixed by punching and integrated with the cylindrical member 19. In the magnet fixing plate thus formed, a comb-shaped connecting portion 20a is provided at a position facing the end face of each of the permanent magnets 16 on the outer peripheral portion.

Next, a method of assembling the permanent magnet rotor according to Embodiment 4 configured as described above will be described. First, as shown in FIG. 15, a plurality of plate members are stacked to form a cylindrical member 19, and at positions opposed to the end surfaces of the respective permanent magnets 16 on the outer peripheral portions of the plate members located at both ends.
A connecting portion 20a formed in a comb shape is provided to form the magnet fixing plate 20, and the magnet fixing plate 20 is pressed and swaged in a progressive press to be fixed integrally with another plate-like member. Next, each permanent magnet 16 is arranged at a position facing the connecting portion 20a, and the permanent magnet 16
By laser welding the end surface of each of the permanent magnets 16 and each connecting portion 20 a of the magnet fixing plate 20, each permanent magnet 16 is connected to the cylindrical member 19.
To form a single unit. And finally, each unit assembled as described above,
A permanent magnet rotor is obtained fixed at a predetermined position on the rotor shaft 14.

As described above, according to the fourth embodiment, the cylindrical member 19 has a laminated structure of a plurality of plate members, and the connecting portions 20a are formed in the plate members located at both ends to form the magnet fixing plate. 20, the connecting portion 20a and the permanent magnet 16
By laser welding with the end face of each permanent magnet 16
Is fixed to the outer peripheral surface of the cylindrical member 19, so that the life of the rotor is extended and the reliability is improved, and the performance of the rotating electric machine is improved as in the case of the second embodiment. Can be.

In the fourth embodiment, the magnet fixing plates 20 which are pressed at the same time and which are positioned at both ends of the plurality of plate members constituting the cylindrical member 19 are separate. May be punched out and fixed to the end face of the cylindrical member 19 by welding, and the connecting portion 20a may be formed as a plurality of protrusions provided with cracks that do not break as in the above-described embodiments. Needless to say, it's good.

Embodiment 5 FIG. FIG. 16 is a diagram showing a configuration of a permanent magnet rotor according to Embodiment 5 of the present invention.
(A) is a front view, (B) is a side sectional view, FIG. 17 and FIG.
FIG. 8 is a view showing an assembling process of a main part of the permanent magnet rotor in FIG. In the figure, rotor shaft 14 and permanent magnet 16 are the same as those in the fourth embodiment. 21 is formed by stacking a plurality of plate-like members including the same number of segment pieces 21a as the permanent magnet 16 formed in the shape shown in FIG. 17 and a thin member 21b that connects and integrates the outer peripheral sides of the segment pieces 21a, The cylindrical member 22 formed by deforming and winding the thin member 21b so that the side ends of the respective segment pieces 21a are in contact with each other. The cylindrical member 22 is formed of the outer peripheral portion of the plate member located at both ends of the cylindrical member 21. This is a magnet fixing plate configured by providing a comb-shaped connecting portion 22 a at a position facing the end face of each permanent magnet 16.

Next, a method of assembling the permanent magnet rotor according to Embodiment 5 configured as described above will be described. First, as shown in FIG. 17, the permanent magnets 16 are respectively inserted into the outer peripheral surface of the plate-like member constituting the cylindrical member 21 at positions corresponding to the respective connection portions 22a of the two magnet fixing plates 22, 22, and The respective permanent magnets 16 are fixed on the outer peripheral surface of each plate-like member constituting the cylindrical member 21 by laser welding the connection portions 22a of the fixing plates 22, 22 and both end surfaces of the permanent magnet 16. Next, as shown in FIG. 18, each thin member 21 b is rolled in while being sequentially deformed, and the side end surfaces of each segment piece 21 a are abutted and fixed, and the cylindrical member 21 b is fixed.
To form one unit. Finally, each unit assembled as described above is fixed at a predetermined position on the rotor shaft 14 to obtain a permanent magnet rotor.

As described above, according to the fifth embodiment, as shown in FIG. 17, the connecting portions 22a are provided on the outer peripheral sides of the laminated plate-like members, but the connecting portions 22a are provided.
And a magnet fixing plate 22 on the outer peripheral surface of the plate-shaped member.
The permanent magnets 1 are located at positions corresponding to the connection portions 22a of the
6 are inserted, and both end faces of these permanent magnets 16 are
Since the unit is formed by laser welding and integrally forming the cylindrical member 2a and forming the cylindrical member 21 by winding them, the workability of assembly is greatly improved. In addition, since the joining position between the magnet fixing plate 22 and the permanent magnet 16 can be arranged on a straight line, the accuracy of the joining position can be easily improved, and when configured as a rotating electric machine, high-precision rotation is achieved. Thus, a cogging torque, torque ripple, rotation unevenness and the like can be reduced.

Embodiment 6 FIG. FIG. 19 is a diagram showing a configuration of a permanent magnet rotor according to Embodiment 6 of the present invention.
(A) is a front view, (B) is a side sectional view. In the figure, rotor shaft 14 and permanent magnet 16 are the same as those in the fifth embodiment. Reference numeral 23 denotes a plurality of plate-like members provided with cracks 23a that do not lead to breakage in the vicinity of the outer peripheral portion.
Reference numeral 4 denotes a cylindrical member integrated in a mold by laminating and crimping these plate members 23, and each permanent magnet 16 is provided on the outer peripheral surface of the cylindrical member 24 in the circumferential direction. They are arranged at a predetermined pitch and fixed by laser welding 25. Each unit thus configured is fitted to the rotor shaft 14 and fixed by press fitting, shrink fitting, keying, bonding or welding to obtain a permanent magnet rotor.

As described above, according to the sixth embodiment, the cylindrical member 24 is formed by laminating the plurality of plate members 23 provided with the cracks 23a that do not lead to fracture near the outer peripheral portion. The permanent magnets are arranged on the outer peripheral surface of the cylindrical member 24 at a predetermined pitch in the circumferential direction and are fixed by laser welding 25. Therefore, the permanent magnets 16 having different thermal expansion coefficients depending on the temperature change of the rotating electric machine. In addition, even if the cylindrical member 24 expands and contracts, a crack 23a which is provided near the outer peripheral portion of each plate member 23 constituting the cylindrical member 24 and elastically deforms in the axial and circumferential directions. Since the difference in the amount is absorbed, good joining is achieved without excessive stress concentrated on the joining surface between the permanent magnet 16 and the cylindrical member 24, so that the life of the rotor is prolonged and the reliability is improved. I do.

Further, since there is no intervening member between the rotor and the stator, there is no need to provide an extra gap between the rotor and the stator, and the permanent magnet 16 and the cylindrical member 24 are not required. Because there is no direct contact with the outer peripheral surface of the
It is also possible to improve the performance of the rotating electric machine.

The plate member 23 shown in FIG. 19 as described above has a crack 23a near the outer periphery that does not break, thereby providing a difference in the amount of expansion and contraction between the permanent magnet 16 and the cylindrical member 24. However, as shown in FIG. 20, a cylindrical member 27 may be formed by stacking plate members 26 provided with cracks 26a that do not break along the magnetic circuit. In this case, distortion is generated in the crack 26a and the magnetic permeability is considerably reduced. Therefore, the crack 26a provided along these magnetic circuits functions as a magnetic barrier. And it is possible to easily obtain a high-efficiency rotor.

As shown in FIG. 21, a plurality of permanent magnets 16 are laser-welded 25 in the axial direction of one cylindrical member 28.
In this case, first, both ends of one permanent magnet 16 are laser-welded 25a and 25b, respectively, and then one end of the other permanent magnet 16 and the outer peripheral contact portions of the two permanent magnets 16 and 16 are laser-welded 25c, respectively. If the distance is set to 25d, the permanent magnets 16 can be arranged in close contact with each other, so that the size in the axial direction can be shortened, and the rotor and, consequently, the rotating electric machine can be downsized.

Embodiment 7 FIG. FIGS. 22 to 25 are views for explaining the invention in the seventh embodiment of the present invention. FIG. 22 shows a state where the permanent magnet 16 and the connecting portion 17a of the magnet fixing plate 17 shown in FIG. 9 are laser-welded. FIG. 23 is a diagram schematically showing a state in which the permanent magnet 16 and the cylindrical member 24 in FIG. 19 are laser-welded,
FIGS. 24 and 25 are schematic diagrams respectively showing the relationship between the welding strength and the laser pulse feed pitch. 22 and 23, d indicates the diameter of a weld bead formed by laser welding, and p indicates the pulse feed pitch of laser welding.

In FIG. 24, when observing the welding state of one bead of laser welding, a molten state is observed at the periphery of the bead, and in the central part of the heat input, the separation of the structure due to a rapid change in heat during welding is observed. As can be seen from the drawing, the strength at the periphery of the bead is the highest, and when the strength of one bead is shown in cross section, two peaks are formed. On the other hand, when observing the case where the pulse feed pitch p becomes smaller than the diameter of the bead as shown in FIG. 25, the heat input becomes large in the overlapping portion of the adjacent beads and becomes the same state as the central portion of the bead. Will be lower. That is, it is not the superimposed intensity but the actual intensity indicated by the broken line in the figure.

Therefore, the permanent magnet 16 and the magnet fixing plate 17
Is fixed to the connecting portion 17a or the cylindrical member 24 by laser welding, the pulse feed pitch p of laser welding is fixed.
Is equal to one of the diameter d of the weld bead formed by laser welding.
By setting the range to 1.5 times, the welding strength can be efficiently maintained at a high level.

Embodiment 8 FIG. When a rare earth permanent magnet such as a neodymium-iron-boron-based magnet or a praseodymium-based magnet is used, for example, as shown in FIG. 1, the magnet fixing plate 3 joined to the permanent magnet 2, and as shown in FIG. A boring treatment, boron diffusion plating or nickel-boron plating is applied to each joint portion such as the magnet fixing plate 20 joined to the permanent magnet 16 and the cylindrical member 24 joined to the permanent magnet 16 as shown in FIG. When energy beam welding such as welding is performed, the boron component contained in each of the permanent magnets 2, 16 and the like is fused in a molten state, so that the weld alloy layer is stabilized and the welding strength is improved.

Embodiment 9 FIG. Similarly to the case of the eighth embodiment, when a rare earth permanent magnet such as a neodymium-iron-boron-based magnet or a praseodymium-based magnet is used, for example, as shown in FIG. 3, the magnet fixing plate 20 joined to the permanent magnet 16 as shown in FIG. 14, and the permanent magnet 16 as shown in FIG.
Is formed of a material containing a boron additive, and energy beam welding, such as laser welding, is performed to form a molten state with the boron component contained in each of the permanent magnets 2, 16 and the like. Due to the fusion, the molten alloy layer is stabilized and the welding strength is improved.

In each of the first to sixth embodiments, a case has been described in which each of the permanent magnet and the magnet fixing plate is joined by laser welding.
In this case, there is no problem since the adhesive layer is not interposed at the position where the magnetic path is obstructed.

[0056]

As described above, according to the first aspect of the present invention, the rotor shaft having the step portion formed to have a large diameter in a part of the axial direction and the outer circumferential surface of the step portion in the circumferential direction are provided. A plurality of permanent magnets which are arranged at a predetermined pitch and have the same length dimension in the axial direction as the step portion, and an end face of each of the annular and outer peripheral permanent magnets
A projection that can be elastically deformed in the axial and circumferential directions at the contact position
A plurality of connection sites are formed,
A pair of magnet fixing plates whose peripheral portions are in contact with the end surfaces of the steps.
In addition, the inner peripheral part of the magnet fixing plate is
Fused parts are respectively fused to the end faces of the corresponding permanent magnets.
Each permanent magnet is attached to the rotor shaft by attaching or bonding.
Since the so that not fixed, it is possible to provide a permanent magnet rotor capable of preventing the degradation of reliability and performance.

According to the second aspect of the present invention, a rotor shaft, a cylindrical member fitted to the rotor shaft and disposed at a predetermined position in the axial direction, and an outer peripheral surface of the cylindrical member Are arranged at a predetermined pitch in the circumferential direction and are
A plurality of permanent magnets having the same length dimension, and a plurality of projecting connection portions which are annular and which can be elastically deformed in the axial and circumferential directions at positions contacting the end faces of the respective permanent magnets in the outer peripheral portion are respectively provided.
And an inner peripheral portion thereof is in contact with the end surface of the cylindrical member.
And a pair of magnet fixing plates that are in contact with each other.
Part on the end surface of the cylindrical member,
Welded or bonded to the end faces of the corresponding permanent magnets
The Rukoto, since the so that to secure each permanent magnet in the cylindrical member, it is possible to provide a permanent magnet rotor capable of preventing the degradation of reliability and performance.

According to a third aspect of the present invention, there is provided a permanent magnet rotor according to the second aspect, in which a plurality of cylindrical members are provided, so that a reduction in reliability and performance can be prevented. can do.

According to a fourth aspect of the present invention, in the third aspect, the cylindrical members are fitted to the rotor shaft such that the positions of the permanent magnets are sequentially shifted by a predetermined angle in the circumferential direction. Therefore, it is possible to provide a permanent magnet rotor capable of preventing reduction in reliability and performance, as well as reduction in cogging torque, torque ripple, and uneven rotation.

According to a fifth aspect of the present invention, in any one of the first to fourth aspects, the magnet fixing plate includes the same number of segment pieces as the permanent magnets and a thin member for connecting the segment pieces. Therefore, it is possible to provide a permanent magnet rotor capable of preventing deterioration of reliability and performance and improving operability of assembly.

According to a sixth aspect of the present invention, in the second aspect, since the cylindrical member is constituted by a plurality of plate members laminated in the axial direction, it is possible to prevent a decrease in reliability and performance. Can be provided.

According to a seventh aspect of the present invention, in the sixth aspect, the plate member is constituted by the same number of segment pieces as the permanent magnets connected to each other on the outer peripheral side, and the side ends of each segment piece are connected to each other. Are formed in a cylindrical shape by contact with the permanent magnet rotor, so that it is possible to provide a permanent magnet rotor capable of improving reliability and performance of the assembly as well as improving assembly workability. .

According to the eighth aspect of the present invention, in the sixth or seventh aspect, each plate-shaped member located at both ends of the cylindrical member also serves as a magnet fixing plate, so that reliability and performance are improved. It is possible to provide a permanent magnet rotor capable of improving the workability of assembly as well as preventing the lowering.

Further, according to the ninth aspect of the present invention, in any one of the first to eighth aspects, since the connecting portion is formed in a comb-like shape, it is possible to easily prevent a decrease in reliability and performance. And a simple permanent magnet rotor can be provided.

According to a tenth aspect of the present invention, in any one of the first to eighth aspects, the connecting portion is formed in a plurality of protrusions having cracks that do not lead to breakage.
It is possible to provide a permanent magnet rotor capable of easily preventing a decrease in reliability and performance.

According to an eleventh aspect of the present invention, a rotor shaft and a plurality of plate-like members each fitted with the rotor shaft and provided with a crack near the outer periphery that does not break are laminated. And a plurality of permanent magnets fixedly arranged at a predetermined pitch in the circumferential direction of the outer peripheral surface of the cylindrical member at a predetermined pitch, thereby preventing a reduction in reliability and performance. And a permanent magnet rotor capable of performing the same.

According to the twelfth aspect of the present invention, in the eleventh aspect, a crack that does not lead to fracture is formed along a desired magnetic circuit, so that the reliability and performance are prevented from deteriorating. A permanent magnet rotor capable of improving the efficiency can be provided.

According to a thirteenth aspect of the present invention, in any one of the first to twelfth aspects, the permanent magnet is fixed by energy beam welding, and the pulse feed pitch of the energy beam welding is formed by energy beam welding. To provide a permanent magnet rotor capable of efficiently maintaining high welding strength as well as preventing deterioration in reliability and performance because the diameter is set to be 1 to 1.5 times the diameter of the welding bead. can do.

According to a fourteenth aspect of the present invention, in any one of the first to thirteenth aspects, a rare earth permanent magnet such as a neodymium-iron-boron-based magnet or a praseodymium-based magnet is used as the permanent magnet. Is fixed by energy beam welding, and the member fixed to the permanent magnet is subjected to boration, boron diffusion plating or nickel-boron plating. A permanent magnet rotor capable of maintaining high strength can be provided.

According to a fifteenth aspect of the present invention, the permanent magnet according to any one of the first to thirteenth aspects uses a rare earth permanent magnet such as a neodymium-iron-boron-based magnet or a praseodymium-based magnet as the permanent magnet. Is fixed by energy beam welding, the member to be fixed to the permanent magnet is formed of a material containing a boron additive.
A permanent magnet rotor capable of efficiently maintaining high welding strength can be provided.

[Brief description of the drawings]

FIG. 1 shows a configuration of a permanent magnet rotor according to Embodiment 1 of the present invention, where (A) is a front view and (B) is a side sectional view.

FIG. 2 is a front view showing a configuration of a main part of the permanent magnet rotor in FIG. 1;

FIG. 3 is a diagram schematically showing details of a crack forming a connection site in FIG. 1;

FIG. 4 is a cross-sectional view illustrating a method of processing a crack forming a connection portion in FIG.

FIG. 5 is a front view showing a configuration of a permanent magnet rotor provided with a magnet fixing plate having a connecting portion formed in a comb shape different from a crack.

6A and 6B show a configuration of a permanent magnet rotor according to Embodiment 2 of the present invention, wherein FIG. 6A is a front view and FIG. 6B is a side sectional view.

7 is a view showing a part of an assembling process of a main part of the permanent magnet rotor in FIG. 6;

FIG. 8 is a view showing a part different from FIG. 7 of an assembling process of a main part of the permanent magnet rotor in FIG. 6;

FIG. 9 is a front view showing a configuration of a main part of the permanent magnet rotor in FIG. 6;

FIG. 10 is a side view showing a different configuration of the permanent magnet rotor according to Embodiment 2 of the present invention.

11A and 11B show a configuration of a permanent magnet rotor according to Embodiment 3 of the present invention, wherein FIG. 11A is a front view and FIG. 11B is a side sectional view.

12 is a diagram showing a part of an assembling process of a main part of the permanent magnet rotor in FIG. 11;

FIG. 13 is a view showing a part different from FIG. 12 of an assembling process of a main part of the permanent magnet rotor in FIG. 11;

14A and 14B show a configuration of a permanent magnet rotor according to Embodiment 4 of the present invention, wherein FIG. 14A is a front view and FIG. 14B is a side sectional view.

15 is a diagram showing an assembly process of the permanent magnet rotor shown in FIG.

16A and 16B show a configuration of a permanent magnet rotor according to Embodiment 5 of the present invention, wherein FIG. 16A is a front view, and FIG. 16B is a side sectional view.

17 is a view showing a part of an assembling process of a main part of the permanent magnet rotor in FIG. 16;

18 is a diagram illustrating a part of the process of assembling the main part of the permanent magnet rotor in FIG. 16 which is different from FIG. 17;

FIG. 19 shows a configuration of a permanent magnet rotor according to Embodiment 6 of the present invention, where (A) is a front view and (B) is a side sectional view.

20A and 20B show different configurations of a permanent magnet rotor according to Embodiment 6 of the present invention, wherein FIG. 20A is a front view, and FIG. 20B is a side sectional view.

FIG. 21 is a partial cross-sectional view showing still another configuration of the permanent magnet rotor according to Embodiment 6 of the present invention.

FIG. 22 is a diagram schematically showing a state where the permanent magnet and the connection portion of the magnet fixing plate shown in FIG. 9 are laser-welded.

FIG. 23 is a diagram schematically showing a state where the permanent magnet and the cylindrical member in FIG. 19 are laser-welded.

FIG. 24 is a diagram showing a distribution of welding strength when a laser pulse feed pitch is larger than a bead diameter.

FIG. 25 is a diagram showing a distribution of welding strength when a laser pulse feed pitch is smaller than a bead diameter.

[Explanation of symbols]

1,14 rotor shaft, 2,16 permanent magnet, 3,13,
17, 18, 20, 22 Magnet fixing plate, 3a, 13a,
17a, 18c, 20a, 22a connection site, 18a,
21a segment piece, 18b, 21b thin member, 8
Half blanked part, 12, 23a, 26a Crack, 15, 1
9, 21, 24, 27, 28 cylindrical member, 25, 25
a, 25b, 25c Laser welding, d diameter, p pitch.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H02K 1/17 H02K 1/27 H02K 15/03

Claims (15)

(57) [Claims] 1. A rotor shaft having a step portion formed on the large-diameter portion of the axial, disposed via a predetermined pitch in the circumferential direction on the outer peripheral surface of the stepped portion the stepped portion and the shaft Same length in direction
A plurality of permanent magnets having dimensions, and a plurality of projecting connection portions which are annular and which can be elastically deformed in the axial and circumferential directions at positions contacting the end faces of the respective permanent magnets at the outer peripheral portion are respectively formed.
And the inner peripheral portion abuts against the end face of the step.
An inner peripheral portion of the magnet fixing plate.
On the end face of the above step,
Welded or adhered to the end face of the corresponding permanent magnet.
The permanent magnet rotor according to any one of the preceding claims , wherein each of the permanent magnets is fixed to the rotor shaft . 2. A rotor shaft, a cylindrical member fitted to the rotor shaft and disposed at a predetermined position in the axial direction, and a predetermined pitch in a circumferential direction on an outer peripheral surface of the cylindrical member. Placed
A plurality of the permanent magnet, the end face an elastically deformable impact in the axial and circumferential directions in a position to abut the respective permanent magnets and the outer peripheral portion an annular having the same length dimension to the cylindrical member and the axial direction
While a plurality of raised connection sites are formed,
A pair of magnets whose inner peripheral portions are in contact with the end surface of the cylindrical member
And a fixing plate, wherein the inner peripheral portion of the magnet fixing plate has a cylindrical shape.
Corresponding to each connecting part of the outer peripheral part on the end face of the member
By welding or bonding to the end face of the permanent magnet respectively
A permanent magnet rotor , wherein each of the permanent magnets is fixed to the cylindrical member . 3. The permanent magnet rotor according to claim 2, wherein a plurality of cylindrical members are provided. 4. The permanent magnet rotation according to claim 3, wherein each cylindrical member is fitted to the rotor shaft such that the positions of the permanent magnets are sequentially shifted by a predetermined angle in the circumferential direction. Child. 5. The magnet fixing plate according to claim 1, wherein the same number of the segment pieces as the permanent magnets and a thin member connecting the respective segment pieces are provided. Permanent magnet rotor. 6. The permanent magnet rotor according to claim 2, wherein the cylindrical member is constituted by a plurality of plate members laminated in the axial direction. 7. The plate-shaped member is constituted by the same number of segment pieces as the permanent magnets connected to each other on the outer peripheral side, and is formed in a cylindrical shape by abutting the side ends of the respective segment pieces. 7. The permanent magnet rotor according to claim 6, wherein: 8. Each of the plate members located at both ends of the cylindrical member also serves as a magnet fixing plate.
Or a permanent magnet rotor according to 7. 9. The permanent magnet rotor according to claim 1, wherein the connecting portion is formed in a comb shape. 10. The permanent magnet rotor according to claim 1, wherein the connecting portion is formed in a plurality of protrusions provided with cracks that do not break. 11. A cylindrical member formed by laminating a rotor shaft, a plurality of plate members each fitted with the rotor shaft and provided with a crack near the outer periphery that does not break, and A permanent magnet rotor, comprising: a plurality of permanent magnets fixedly arranged at a predetermined pitch in a circumferential direction on an outer peripheral surface of a cylindrical member. 12. The crack that does not lead to fracture is formed along a desired magnetic circuit.
A permanent magnet rotor as described. 13. The fixing of the permanent magnet is performed by energy beam welding, and the pulse feed pitch of the energy beam welding is set in a range of 1 to 1.5 times the diameter of a weld bead formed by the energy beam welding. The permanent magnet rotor according to any one of claims 1 to 12, wherein: 14. A method in which a rare earth permanent magnet such as a neodymium-iron-boron magnet or a praseodymium magnet is used as the permanent magnet and the permanent magnet is fixed by energy beam welding. The permanent magnet rotor according to any one of claims 1 to 13, wherein the permanent magnet rotor has been subjected to boration treatment, boron diffusion plating, or nickel-boron plating. 15. A permanent magnet using a rare earth permanent magnet such as a neodymium-iron-boron magnet or a praseodymium magnet and fixing the permanent magnet by energy beam welding, wherein the member fixed to the permanent magnet is The permanent magnet rotor according to any one of claims 1 to 13, wherein the permanent magnet rotor is formed of a material containing a boron additive.