JP2004236477A - Permanent magnet rotor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a permanent magnet rotor exhibiting excellent magnetic characteristics and sufficient mechanical strength in which heat generation can be suppressed. <P>SOLUTION: The permanent magnet rotor comprises a rotor yoke 20 having salient pole parts 23 on the outer circumferential part and provided with a magnet insertion hole 24 in the salient pole part 23, permanent magnet pieces 40 inserted into the magnet insertion holes 24, and end face plates 30A and 30B arranged along the end face of the rotor yoke 20 and closing the magnet insertion holes 24. The end face plate 30A, 30B is provided, on the outer circumferential part thereof, with a plurality of stop claws 34 projecting in the axial direction of the rotor yoke 20 and the stop claw 34 is stopped at the level difference part 26 of the salient pole part 23. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a permanent magnet rotor having a permanent magnet embedded in a rotor core.
[0002]
[Prior art]
2. Description of the Related Art As a rotor used in a rotating electric machine such as an electric motor or a generator, a permanent magnet rotor in which a permanent magnet is embedded in a rotor core is known (for example, see Patent Documents 1 and 2). In the conventional permanent magnet type rotor, for example, as shown in FIG. 7, a large number of salient pole portions 91 are provided on an outer peripheral portion of a rotor core 90 formed by laminating many silicon steel plates, and a rotor core 90 is provided on each salient pole portion 91. The magnet insertion holes 92 penetrating in the axial direction are provided, and a permanent magnet piece 93 is inserted and arranged in each magnet insertion hole 92. Here, the width t of a portion (hereinafter, referred to as a holding portion) 94 of the salient pole portion 91 which is located on the outer side in the circumferential direction of the magnet insertion hole 92 is reduced in order to reduce a leakage magnetic flux in the rotor. (See, for example, Patent Document 3).
[0003]
[Patent Document 1]
JP-A-5-284680 [Patent Document 2]
JP-A-6-269140 [Patent Document 3]
JP-A-2002-209350
[Problems to be solved by the invention]
However, the holding portion 94 is a portion where the stress due to the centrifugal force is concentrated when the permanent magnet type rotor rotates, and if the width t of the holding portion 94 is made too small, the mechanical strength is reduced. On the other hand, if the width t of the holding portion 94 is increased with priority given to the mechanical strength, the magnetic flux of the permanent magnet piece 93 is short-circuited, and the heat generated by the magnet is increased, which is disadvantageous.
Accordingly, the present invention provides a permanent magnet rotor having excellent magnetic properties, capable of suppressing heat generation, and having sufficient mechanical strength.
[0005]
[Means for Solving the Problems]
In order to solve the above problem, the invention according to claim 1 has a salient pole portion (for example, a salient pole portion 23 in an embodiment described later) on an outer peripheral portion, and a magnet insertion hole (for example, A rotor core (for example, a rotor yoke 20 in an embodiment to be described later) provided with a magnet insertion hole 24 in an embodiment to be described later, and a permanent magnet piece (for example, an embodiment to be described later) inserted into the magnet insertion hole. Permanent magnet pole piece 40) and end plates (for example, end plates 30A and 30B in an embodiment described later) disposed along the end surface of the rotor core and closing the magnet insertion holes. In a rotor (for example, a permanent magnet rotor 1 in an embodiment to be described later), the end face plate has a plurality of locking claws (for example, an embodiment to be described later) protruding on an outer peripheral portion in an axial direction of the rotor core. It includes a locking claw 34) in the form, the locking pawl, characterized in that is engaged with the outer peripheral surface of the salient pole portion.
[0006]
With this configuration, when a centrifugal force causes a radially outward pulling force to act on the rotor core and the permanent magnet pieces, the locking claws of the end face plate can resist this force. That is, since a part of the stress due to the centrifugal force can be received by the locking claw of the end face plate, the stress in the holding portion adjacent to the magnet insertion hole can be reduced, and the width of the holding portion can be reduced. it can.
[0007]
According to a second aspect of the present invention, in the first aspect of the present invention, a step portion (for example, a step portion 26 in an embodiment described later) is provided at an end of the outer peripheral surface of the salient pole portion, and the step portion is provided. Wherein the locking claw is locked.
With this configuration, the locking claw of the end face plate does not protrude from the outer peripheral surface of the salient pole portion.
[0008]
The invention according to claim 3 has a salient pole portion (for example, a salient pole portion 23 in an embodiment described later) on an outer peripheral portion, and a magnet insertion hole (for example, a magnet insertion hole in an embodiment described later). A rotor core provided with the hole 24) (for example, the rotor yoke 20 in an embodiment described later), a permanent magnet piece inserted in the magnet insertion hole (for example, a permanent magnetic pole piece 40 in an embodiment described later), A permanent magnet rotor (for example, an end plate 30A, 30B in an embodiment described later) disposed along an end surface of the rotor core and closing the magnet insertion hole (for example, an embodiment described later) In the permanent magnet type rotor 1) according to the embodiment, the end face plate includes a plurality of locking claws (for example, locking claws 35 according to an embodiment described later) that protrude in the axial direction of the rotor core. Wherein the locking claw is engaged with the outer peripheral surface of the inserted permanent magnet pieces in the magnet insertion holes.
[0009]
With this configuration, when a centrifugal force exerts a radially outward pulling force on the permanent magnet pieces, the locking claws of the end face plate can resist this force. That is, since a part of the stress due to the centrifugal force can be received by the locking claw of the end face plate, the stress in the holding portion adjacent to the magnet insertion hole can be reduced, and the width of the holding portion can be reduced. it can.
[0010]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an embodiment of a permanent magnet type rotor according to the present invention will be described with reference to the drawings of FIGS.
1 and 2 are a plan view and an exploded perspective view of a permanent magnet type rotor (hereinafter abbreviated as a rotor) 1 according to the present invention, which can be used for a rotating electric machine such as a motor or a generator.
The rotor 1 includes a rotor 10, a rotor yoke (rotor core) 20, a pair of end plates 30A and 30B, and a number of permanent magnetic pole pieces 40.
[0011]
The rotor 10 has a hollow drum shape, and is integrally formed by casting or forging. A chamfer for guiding when the rotor yoke 20 is pressed into a corner which is a boundary between the outer peripheral surface 11 and the one end surface 12 of the cylindrical rotor. On the other hand, at the corner which is the boundary between the outer peripheral surface 11 and the other end surface 13 of the rotor, the end plate 30A is brought into contact with the extending portion 13a extending outward from the other end surface 13. Relief groove 13b is formed. Three grooves 14 are formed in the outer peripheral surface 11 of the rotor at equal intervals in the circumferential direction along the axial direction.
[0012]
The end plates 30A and 30B are exactly the same, but the mounting directions along the axial direction are reversed. Here, the end plate 30A will be described, and the description of the end plate 30B will be omitted. The end face plate 30A has an annular shape, and the inner diameter of a hole 32 formed in the center of the plate portion 31 is formed slightly smaller than the outer diameter of the outer peripheral surface 11 of the rotor 10 for press-fitting. In addition, three projections 33 are provided radially inward at the inner peripheral end of the plate portion 31, and a number of locking claws 34 are provided at predetermined intervals in the circumferential direction at the outer peripheral end at right angles in the thickness direction. It is provided standing up. That is, the locking claw 34 protrudes along the axial direction of the end face plate 30A. The end plates 30A and 30B are made of, for example, a non-magnetic austenitic stainless steel SUS304.
[0013]
The rotor yoke 20 is formed by laminating a number of electromagnetic steel sheets 28 having the same shape and the same size, and has an annular shape. At the center of the rotor yoke 20, a through hole 21 into which the rotor 10 is inserted is provided, and three projections 22 are provided on the inner peripheral surface thereof at equal intervals in the circumferential direction.
The rotor yoke 20 is provided with a number of salient pole portions 23 on its outer peripheral portion, and a magnet insertion hole 24 into which a permanent magnet piece 40 is inserted is provided on the base side of each salient pole portion 23.
[0014]
As shown in FIG. 3, the width dimension t of a portion (hereinafter, referred to as a holding portion) 25 of the salient pole portion 23 which is located on the outer side in the circumferential direction of the magnet insertion hole 24 is for suppressing a short circuit of the magnetic flux of the permanent magnetic pole piece 40. , And is set very small to suppress heat generation. Further, the outer circumferential end of each salient pole portion 23 of the rotor yoke 20 has substantially the same width as the locking claw 34 of the end face plates 30A and 30B and a depth substantially equal to the thickness of the locking claw 34. The formed steps 26, 26 are provided.
[0015]
The rotor 1 is assembled as follows, for example.
First, the end face plate 30A is press-fitted from the one end face 12 side of the rotor 10 to the outer peripheral face 11 of the rotor 10 and fitted therein. At this time, the protrusion 33 of the end face plate 30A is press-fitted while being engaged with the groove 14 of the outer peripheral surface 11 of the rotor 10.
Next, the rotor yoke 20 is pressed into the outer peripheral surface 11 of the rotor 10 from the one end surface 12 side of the rotor 10 and fitted therein. At that time, the protrusion 22 of the rotor yoke 20 is press-fitted while engaging with the groove 14 of the outer peripheral surface 11 of the rotor 10. By pressing the projections 33 and 22 into engagement with the grooves 14 in this manner, the projections 33 of the end face plate 30A and the projections 22 of the rotor yoke 20 are arranged so as to coincide with each other, and as shown in FIG. Are engaged with the step 26 of the salient pole portion 23 of the rotor yoke 20. As a result, the locking claw 34 is locked on the outer peripheral surface of the salient pole portion 23.
[0016]
Subsequently, one permanent magnetic pole piece 40 is inserted into each magnet insertion hole 24 of the rotor yoke 20, and then the end face plate 30 </ b> B is press-fitted from one end face 12 side of the rotor 10 to the outer peripheral face 11 of the rotor 10. . At that time, the protrusion 33 of the end face plate 30B is press-fitted while being engaged with the groove 14 of the outer peripheral surface 11 of the rotor 10. Therefore, similarly to the end face plate 30A, the protrusion 33 of the end face plate 30B and the protrusion 22 of the rotor yoke 20 are arranged so as to coincide with each other, and each locking claw 34 of the end face plate 30B is connected to the stepped portion 26 of the salient pole portion 23 of the rotor yoke 20. Is locked. Thereby, the locking claw 34 of the end face plate 30B is also locked to the outer peripheral surface of the salient pole portion 23.
[0017]
By assembling as described above, the rotor 10, the rotor yoke 20, the permanent magnetic pole piece 40, and the end face plates 30A and 30B are integrated, and the rotor 1 as shown in FIG. 1 is completed. In the rotor assembled in this manner, the openings at both ends of each magnet insertion hole 24 are closed by the end plates 30A and 30B, and the permanent magnetic pole piece 40 is prevented from coming off the rotor yoke 20. The locking claw 34 is locked only to the step 26 of the plurality of electromagnetic steel plates 28 arranged near both ends in the axial direction of the rotor yoke 20, and the step of the electromagnetic steel plate 28 arranged in the central portion in the axial direction. The part 26 is not locked. With this configuration, it is not necessary to prepare a plurality of types of electromagnetic steel sheets 23a, and it is possible to use only one type.
[0018]
In the rotor 1 configured as described above, the projections 22 of the rotor yoke 20 and the projections 33 of the end plates 30A, 30B are engaged with the grooves 14 of the rotor 10, and the locking claws of the end plates 30A, 30B. Since 34 is locked to the step 26 formed on the outer periphery of the rotor yoke 20, the rotor 10, the rotor yoke 20, and the end plates 30A and 30B do not shift from each other in the circumferential direction.
[0019]
In addition, since the locking claws 34 of the end plates 30A and 30B are locked to the step portions 26 formed on the outer periphery of the rotor yoke 20, the salient pole portions 23 of the rotor yoke 20 by centrifugal force when the rotor 1 rotates. When a radial pulling force acts on the permanent magnet piece 40, the locking claws 34 of the end face plates 30A and 30B and the holding portion 25 of the rotor yoke 20 oppose this force and prevent the holding portion 25 from being damaged. . That is, since a part of the stress due to the centrifugal force is received by the locking claws 34 of the end face plates 30A and 30B, the stress in the holding portion 25 of the rotor yoke 20 can be reduced. As a result, the width t of the holding portion 25 can be reduced.
Since the locking claw 34 is locked to the step 26, the outer surface of the locking claw 34 and the outer peripheral surface of the salient pole portion 23 are flush with each other, and the gap between the stator of the rotating electric machine and the rotor yoke 20 is increased. No need.
[0020]
Therefore, in the rotor 1, the mechanical strength of the rotor 1 can be sufficiently increased even if the width dimension t of the holding portion 25 is reduced. In other words, the mechanical strength of the rotor 1 can be increased without increasing the width t of the holding portion 25. Further, since the width dimension of the holding portion 25 can be reduced, a short circuit of the magnetic flux of the permanent magnetic pole piece 40 can be suppressed, and heat generation can be suppressed.
[0021]
In the above-described embodiment, the step portion 26 is provided on the salient pole portion 23 of the rotor yoke 20, and the locking claw 34 of the end face plates 30A, 30B is locked to the step portion 26, as shown in FIG. Then, a cut is made in a predetermined portion of the plate portion 31 of the end face plates 30A, 30B, and a portion surrounded by the cut is projected in the axial direction to form a locking claw 35, and as shown in FIG. Claw insertion holes 27 bulging radially outward are provided at both ends of each magnet insertion hole 24 continuously with the magnet insertion holes 24, and locking claws 35 are locked at both ends of the outer peripheral surface of the permanent magnetic pole piece 40. You may do so.
[0022]
In this way, when the centrifugal force generated when the rotor 1 rotates causes a radially outward pulling force to act on the permanent magnet piece 40, the locking claws 35 of the end face plates 30A and 30B oppose this force. The permanent pole piece 40 is prevented from moving radially outward. As a result, the force that pulls the permanent magnetic pole piece 40 outward in the radial direction does not act on the salient pole portion 23 of the rotor yoke 20 and the stress due to the centrifugal force in the holding portion 25 can be reduced. Can be reduced.
Therefore, even with this configuration, the mechanical strength of the rotor 1 can be increased without increasing the width t of the holding portion 25, and the width of the holding portion 25 can be reduced. Therefore, a short circuit of the magnetic flux of the permanent magnetic pole piece 40 can be suppressed, and heat generation can be suppressed.
[0023]
【The invention's effect】
As described above, according to the first aspect of the invention, a part of the stress due to the centrifugal force can be received by the locking claw of the end face plate, so that the stress of the holding portion adjacent to the magnet insertion hole is reduced. The width of the holding portion can be reduced. Therefore, the mechanical strength of the permanent magnet type rotor can be sufficiently increased without increasing the width of the holding portion, and the width of the holding portion is reduced to short-circuit the magnetic flux of the permanent magnetic pole piece. , And an excellent effect that heat generation can be suppressed.
[0024]
According to the invention according to claim 2, in addition to the effect of claim 1, since the locking claw of the end face plate does not protrude from the outer peripheral surface of the salient pole portion, the gap between the rotor core and the stator is not increased. This has the effect of ending.
[0025]
According to the invention according to claim 3, a part of the stress due to the centrifugal force can be received by the locking claw of the end face plate, so that the stress of the holding portion adjacent to the magnet insertion hole can be reduced, and the holding portion can be reduced. Can be reduced in width. Therefore, the mechanical strength of the permanent magnet type rotor can be sufficiently increased without increasing the width of the holding portion, and the width of the holding portion is reduced to short-circuit the magnetic flux of the permanent magnetic pole piece. , And an excellent effect that heat generation can be suppressed.
[Brief description of the drawings]
FIG. 1 is a plan view of a permanent magnet type rotor according to a first embodiment of the present invention.
FIG. 2 is an exploded perspective view of the permanent magnet rotor according to the first embodiment.
FIG. 3 is a sectional view of a main part of the permanent magnet type rotor according to the first embodiment.
FIG. 4 is an external perspective view of a main part of the permanent magnet rotor according to the first embodiment.
FIG. 5 is an external perspective view of a main part of an end face plate used in a permanent magnet type rotor according to a second embodiment of the present invention.
FIG. 6 is a sectional view of a main part of a permanent magnet rotor according to the second embodiment.
FIG. 7 is a sectional view of a main part of a conventional permanent magnet type rotor.
[Explanation of symbols]
1 permanent magnet type rotor 20 rotor yoke (rotor core)
23 salient pole portion 24 magnet insertion hole 26 step portions 30A, 30B end face plates 34, 35 locking claw 40 permanent magnetic pole piece

Claims (3)

A rotor core having a salient pole portion on an outer peripheral portion and a magnet insertion hole provided in the salient pole portion; a permanent magnet piece inserted into the magnet insertion hole; and a magnet arranged along an end face of the rotor core. An end plate closing the insertion hole, and a permanent magnet type rotor having:
The end plate is provided with a plurality of locking claws protruding in an axial direction of the rotor core on an outer peripheral portion, and the locking claws are locked on an outer peripheral surface of the salient pole portion. Rotor. 2. The permanent magnet type rotor according to claim 1, wherein a step portion is provided at an end of an outer peripheral surface of the salient pole portion, and the locking claw is locked on the step portion. 3. A rotor core having a salient pole portion on an outer peripheral portion and a magnet insertion hole provided in the salient pole portion; a permanent magnet piece inserted into the magnet insertion hole; and a magnet arranged along an end face of the rotor core. An end plate closing the insertion hole, and a permanent magnet type rotor having:
The end plate includes a plurality of locking claws protruding in the axial direction of the rotor core, and the locking claws are locked to an outer peripheral surface of a permanent magnet piece inserted into the magnet insertion hole. Permanent magnet rotor.

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