Rotor of electrical rotating device

Abstract

A rotor (2) of an electrical rotating device comprises: a rotor core (5); a permanent magnet (6) mounted on an outer peripheral surface of the rotor core (5); armoring (7) that is divided into a plurality of parts in an axial direction, which is the direction of a rotation axis (O) of the rotor (2), and holds the permanent magnet (6) from the outside; a seal tube (8) clamped between the permanent magnet and the armoring (7); and a pair of end plates (9) that clamps the rotor core (5) and the permanent magnet (6) from both sides in the axial direction. An inner engagement protrusion (8a) that engages with an outer peripheral edge of the end plate (9) is formed on an inner peripheral edge of one end of the seal tube (8) in the axial direction.

Description

Rotor of a rotating electrical machine

[0001] The present disclosure relates to a rotor of an electrical rotating device.

[0002] Patent Document 1 below discloses a rotor for a rotating electric machine. The rotor disclosed in Patent Document 1 is a surface permanent magnet (SPM) type rotor for a rotating electric machine, and has multiple permanent magnets attached circumferentially to its outer periphery. The multiple permanent magnets on the outer periphery also form multiple rows parallel to the direction of the rotor's rotation axis. An armor is also attached to the outside of the permanent magnets to prevent the permanent magnets from coming off the rotor due to the centrifugal force of the rotating rotor. In Patent Document 1, the armor is called a retaining sleeve. In order to suppress heat generation due to eddy current loss in the armor, the armor is divided into multiple pieces in the axial direction, which is the direction of the rotor's rotation axis. In Patent Document 1, the divided armor, i.e., the divided retaining sleeve, is called a divided sleeve.

[0003] In addition, in the rotor disclosed in Patent Document 1, flow paths for a coolant for cooling the rotor including permanent magnets are formed on the outer or inner peripheral surfaces of the permanent magnets along the axial direction. The rotor also includes a seal pipe to prevent the coolant from leaking from the inside to the outside of the rotor through gaps between axially adjacent permanent magnets and gaps between axially adjacent armour rings due to the centrifugal force of the rotating rotor. The seal pipe is called a seal ring in Patent Document 1. The seal pipe is provided between the permanent magnets and the armour ring.

[0004] International Publication No. 2021 / 192444

[0005] In the rotor disclosed in the above-mentioned Patent Document 1, there is a concern that the seal tube may be misaligned with respect to the permanent magnet in the axial direction of the rotor.

[0006] Therefore, an object of the rotor for a rotating electric machine according to the present disclosure is to effectively prevent the seal tube from being misaligned with the permanent magnet in the axial direction of the rotor.

[0007] The rotor of the rotating electric machine according to the present disclosure comprises a rotor core, a plurality of permanent magnets arranged circumferentially on the outer surface of the rotor core, an armature divided into a plurality of pieces in the axial direction, which is the direction of the rotor's rotation axis, and holding the permanent magnets from the outside, a seal tube sandwiched between the permanent magnets and the armature, and a pair of end plates sandwiching the rotor core and the plurality of permanent magnets from both sides in the axial direction, and an inner engaging protrusion that engages with the outer peripheral edge of the end plate is formed on the inner peripheral edge at one axial end of the seal tube.

[0008] The inner circumferential edge of the seal pipe at the other axial end may also be formed with the inner engaging projection that engages with the outer circumferential edge of the end plate.

[0009] Here, an engagement surface of the inner engagement projection with the outer circumferential edge of the end plate may be an annular plane perpendicular to the axial direction.

[0010] Alternatively, the surface of the inner engaging projection that engages with the outer peripheral edge of the end plate may be an annular tapered surface whose inner diameter decreases toward the axial end edge of the seal pipe.

[0011] Furthermore, an outer engaging protrusion that engages with an inner peripheral edge of the armor ring may be further formed on an outer peripheral edge of the seal pipe at the one axial end.

[0012] The outer circumferential edge of the seal pipe at the other axial end may also be formed with the outer engaging projection that engages with the inner circumferential edge of the armoring.

[0013] Here, an engagement surface of the outer engagement projection with the inner peripheral edge of the armoring may be an annular plane perpendicular to the axial direction.

[0014] Alternatively, the engaging surface of the outer engaging projection with the inner peripheral edge of the armoring may be an annular tapered surface whose outer diameter increases toward the axial end edge of the seal pipe.

[0015] According to the rotor for a rotating electric machine according to the present disclosure, it is possible to effectively prevent the seal tube from being displaced relative to the permanent magnet in the axial direction of the rotor.

[0016] Fig. 1 is a cross-sectional view including the rotation axis of a rotor according to an embodiment. Fig. 2 is a cross-sectional view perpendicular to the rotation axis of the rotor. Fig. 3 is an enlarged cross-sectional view of a main part of a rotor according to a first embodiment. Fig. 4 is an enlarged cross-sectional view of a main part of a rotor according to a second embodiment.

[0017] Hereinafter, the rotor 2 of the rotating electrical machine 1 according to the embodiments (first and second embodiments) will be described with reference to the drawings.

[0018] The rotor 2 of the embodiment is a rotor of a rotating electric machine 1. The rotating electric machine 1 of the embodiment functions as a generator. FIG. 1 is a cross-sectional view of the rotor 2 including the rotation axis O, and FIG. 2 is a cross-sectional view perpendicular to the rotation axis O. Note that FIG. 1 is also a cross-sectional view taken along line I-I in FIG. 2, showing only one side with respect to the rotation axis O. FIG. 2 is also a cross-sectional view taken along line II-II in FIG. 1. The differences between the first embodiment and the second embodiment cannot be seen in FIGS. 1 and 2. FIGS. 3 and 4 are enlarged cross-sectional views of a portion X in FIG. 1, with FIG. 3 showing the first embodiment and FIG. 4 showing the second embodiment. Note that the size ratios of the components in FIG. 1 and FIG. 2 are slightly different, but this does not hinder understanding of the embodiments.

[0019] As shown in Fig. 1, the rotating electric machine 1 includes a rotor 2 that rotates around a rotation axis O, and a stator 3 disposed on the outside of the rotor 2. A rotating shaft 4 of the rotor 2 is formed integrally with a rotating shaft of an external device (not shown) provided on the left side of Fig. 1. The rotating electric machine 1, which serves as a generator, generates electricity when the rotor 2 is rotated by the rotating shaft 4, which is rotated by the external device. In this embodiment, the rotating shaft 4 is a hollow shaft. The rotating shaft 4 extends from the rotor 2 toward the external device and is rotatably supported by bearings inside the external device.

[0020] The rotor 2 includes a rotor core 5 fixed to the rotating shaft 4, a plurality of permanent magnets 6 attached to the outer periphery of the rotor core 5 in a circumferentially aligned arrangement, and an armor ring 7 arranged radially outward of the permanent magnets 6. The rotating electric machine 1 serving as a generator in this embodiment is an SPM-type generator. A cross section perpendicular to the rotation axis O of the rotor 2 is approximately octagonal as shown in FIG. 2 , and the rotor core 5 is hollow inside. The permanent magnets 6 are attached to each side of the octagon of the rotor core 5, with eight permanent magnets 6 arranged in the circumferential direction. On the peripheral surface of the rotor core 5, the permanent magnets 6 form eight rows parallel to the rotation axis O. Hereinafter, the direction of the rotation axis O of the rotor 2 will also be simply referred to as the axial direction.

[0021] The armor 7 is a cylindrical metal member disposed on the outside of the permanent magnet 6, and holds the permanent magnet 6 so that it does not come off the rotor core 5 due to centrifugal force when the rotor 2 rotates. The armor 7 may be formed from a material other than metal, for example, carbon fiber reinforced plastic (CFRP). Eddy currents are generated in the metal armor 7 as the magnetic flux density varies with the rotation of the rotor 2, and heat is generated in the armor 7. In this embodiment, in order to prevent the permanent magnet 6 from being heated by the heat of the armor 7, the entire armor 7 is composed of a large number of divided armors 7a each having a small axial width in order to reduce these eddy currents.

[0022] Adjacent armour ring segments 7a are in close contact with each other, and the entire armour ring 7 forms a cylindrical shape that covers all of the permanent magnets 6. Because the armour ring 7 is made up of multiple annular armour ring segments 7a, the electrical resistance between adjacent armour ring segments 7a increases and the flux linkage per armour ring segment 7a decreases, reducing eddy currents and loss. As a result, heat generation due to eddy current loss can also be reduced.

[0023] Additionally, a cylindrical seal pipe 8 is sandwiched between the permanent magnet 6 and the armature 7. The seal pipe 8 is a member that prevents the coolant circulating inside the rotor 2 from leaking from the joints of the divided armature 7a to the outside of the rotor 2. The circulation of the coolant and the seal pipe 8 will be described in detail later.

[0024] A pair of end plates 9 are fixed to both axial end surfaces of the rotor core 5, sandwiching the permanent magnets 6 from both axial sides. A retaining disk 10 or a retaining ring 11 is disposed in a hole formed in the center of each circular end plate 9. The retaining disk 10 is fixed to the end of the rotating shaft 4, which is a hollow shaft, opposite the external device (the end on the right side in FIG. 1). The retaining ring 11 is fixed to a position of the rotating shaft 4 closer to the external device (the left side in FIG. 1).

[0025] At part X in Figure 1, the outer peripheral edge of the end plate 9 contacts the inner peripheral surface of the seal pipe 8. Part X will be described in detail later with reference to Figures 3 and 4. An O-ring is attached to the contact peripheral surface between the outer peripheral edge of the retainer disk 10 and the inner peripheral edge of the end plate 9 to prevent leakage of the coolant. A coolant inlet 13 is formed in the center of the retainer disk 10, and this inlet 13 is connected to a coolant delivery pump (not shown) and a coolant supply source (not shown).

[0026] Next, the coolant circulation path will be described with reference to Figure 1. A circular storage chamber 14 is formed inside the center of the retaining disk 10 to receive the coolant supplied to the interior of the rotor 2 from the inlet 13. The rotation axis O of the rotor 2 passes through the center of the circular storage chamber 14. Twelve outlet holes 14a are formed on the inner circumferential surface of the storage chamber 14. Radial inlet flow passages P1 are formed from each outlet hole 14a, radiating from the rotation axis O. That is, each radial inlet flow passage P1 is extended radially in the radial direction of the rotor 2, reaching the position of the permanent magnets 6.

[0027] More specifically, each radial introduction passage P1 is formed by a first segment P1a formed on the rotating shaft 4 and a second segment P1b formed on the end plate 9. The second segment P1b formed on the end plate 9 is formed as a groove on the inner surface of the end plate 9. The radially outer end of each radial introduction passage P1 is connected to an annular introduction passage P2 formed between the outer periphery of the end plate 9 and the permanent magnet 6. The annular introduction passage P2 is formed between the radially outer end of each radial introduction passage P1 and the seal pipe 8, and the center of the annular introduction passage P2 coincides with the rotation axis O. At multiple circumferential locations inside the annular introduction passage P2, the inner surface of the end plate 9 contacts the permanent magnet 6 so as not to block the flow of coolant through the annular introduction passage P2.

[0028] As shown in FIG. 2 , five axial flow passages P3 are formed on the outer peripheral surface of each permanent magnet 6, parallel to the axial direction. The axial flow passages P3 are coolant flow passages formed on the surface of the permanent magnet 6. One end of each axial flow passage P3 is connected to the annular inlet passage P2. The other end of each axial flow passage P3 is connected to an annular outlet passage P4 similar to the annular inlet passage P2. A plurality of radial outlet passages P5 similar to the radial inlet passages P1 are formed radially, i.e., radially, and their radially outer ends are connected to the annular outlet passage P4. The radial outlet passages P5 are formed by grooves formed on the inner surface of the end plate 9 and grooves formed on the end face of the rotor core 5. The radially inner ends of each radial outlet passage P5 reach the rotating shaft 4 and are connected to an annular outlet passage P6 formed between the rotating shaft 4 and the retaining ring 11. The annular outlet passage P6 is connected to an external device (not shown).

[0029] The flow of coolant inside the rotor 2 will now be described. The coolant supplied to the reservoir chamber 14 flows toward the outer periphery in the radial introduction passages P1 due to the supply liquid pressure and the centrifugal force generated by the rotation of the rotor 2. The coolant flowing through the radial introduction passages P1 comes into contact with the end face of the rotor core 5 and also cools the rotor core 5. The coolant is introduced from the radial introduction passages P1 through the annular introduction passage P2 into the axial passages P3, and cools the permanent magnets 6 while flowing through the axial passages P3. In this embodiment, the axial passages P3 are formed on the surface of the permanent magnets 6 close to the armature 7, and therefore the coolant flowing through the axial passages P3 also cools the armature 7 through the seal pipes 8.

[0030] The coolant that has flowed through the axial flow path P3 is discharged to the annular outlet flow path P4 and further to the radial outlet flow path P5. The supply pressure of the coolant causes the coolant to flow through the radial outlet flow path P5 toward the rotation axis O and is discharged into the annular discharge flow path P6. The coolant discharged into the annular discharge flow path P6 is supplied to an external device (not shown).

[0031] Next, the seal pipe 8 disposed between the permanent magnet 6 and the armature 7 will be described. As described above, the armature 7 is composed of divided armature segments 7a that are divided in the axial direction. As a result, joints are formed between adjacent divided armature segments 7a. The seal pipe 8 prevents the coolant flowing through the axial flow path P3 from leaking from the joints of the divided armature segments 7a due to centrifugal force caused by the rotation of the rotor 2. The seal pipe 8 covers the joints of the divided armature segments 7a from the radially inner side of the armature 7, preventing the coolant from leaking from the joints.

[0032] The seal pipe 8 is attached to the outside of the permanent magnet 6 by first expanding it in the radial direction using a shrink fitting (press-fit) or the like and then reducing its diameter. There is a concern that the seal pipe 8 attached in this manner may become misaligned in the axial direction with respect to the permanent magnet 6. Therefore, in the first embodiment, as shown in Figure 3, which is an enlarged view of part X in Figure 1, an inner engaging protrusion 8a that engages with the outer circumferential edge of the end plate 9 is formed on the inner circumferential edge of one axial end of the seal pipe 8 (the end on the right side in Figure 1).

[0033] The inner engaging protrusion 8a is formed around the entire inner periphery of the seal pipe 8. Furthermore, an engaging step that engages with the inner engaging protrusion 8a is formed on the outer periphery of the end plate 9 to match the shape of the inner engaging protrusion 8a. In this embodiment, the engaging surface of the inner engaging protrusion 8a with the outer periphery of the end plate 9 is an annular plane perpendicular to the axial direction. By forming the inner engaging protrusion 8a that engages with the outer periphery of the end plate 9 on the inner periphery of the seal pipe 8 in this manner, leftward displacement of the seal pipe 8 relative to the permanent magnet 6 in Figure 3 can be prevented. Furthermore, because the engaging surface of the inner engaging protrusion 8a with the outer periphery of the end plate 9 is an annular plane perpendicular to the axial direction, the seal pipe 8 does not move over the engaging surface and become displaced leftward in Figure 3, and the seal pipe 8 and the end plate 9 are firmly engaged. As a result, axial displacement of the seal pipe 8 relative to the permanent magnet 6 is reliably prevented.

[0034] In this embodiment, an inner engaging projection 8a that engages with the outer peripheral edge of the end plate 9 is also formed on the inner peripheral edge of the other axial end of the seal pipe 8 (the left end in FIG. 1 ). Therefore, in this embodiment, rightward positional displacement of the seal pipe 8 relative to the permanent magnet 6 at the left end in FIG. 1 can also be prevented. That is, in this embodiment, positional displacement of the seal pipe 8 relative to the permanent magnet 6 in both directions in FIG. 1 is prevented. Again, because the engagement surface of the inner engaging projection 8a with the outer peripheral edge of the end plate 9 is an annular plane perpendicular to the axial direction, the seal pipe 8 will not move over the engagement surface and be displaced rightward at the left end in FIG. 1 , and the seal pipe 8 and the end plate 9 are firmly engaged with each other.

[0035] The armor ring 7 is also attached to the outside of the seal pipe 8 by first expanding it in the radial direction by shrink fitting or the like and then reducing its diameter. There is also a concern that the armor ring 7 attached in this manner may become misaligned in the axial direction with respect to the seal pipe 8. Therefore, in this embodiment, as shown in Figure 3, an outer engaging protrusion 8b that engages with the inner peripheral edge of the armor ring 7 is also formed on the outer peripheral edge at one axial end of the seal pipe 8 (the end on the right side in Figure 1). More specifically, an outer engaging protrusion 8b that engages with the inner peripheral edge of the axially outermost divided armor ring 7a is formed at one axial end of the seal pipe 8.

[0036] The outer engaging projections 8b are formed around the entire outer periphery of the seal pipe 8. Furthermore, an engaging step that engages with the outer engaging projections 8b is formed on the inner periphery of the armor 7, i.e., the outermost divided armor ring 7a, to match the shape of the outer engaging projections 8b. In this embodiment, the engaging surface of the outer engaging projections 8b with the inner periphery of the armor 7 is an annular plane perpendicular to the axial direction. Forming the outer engaging projections 8b that engage with the inner periphery of the armor 7 on the outer periphery of the seal pipe 8 in this manner prevents leftward displacement of the seal pipe 8 relative to the armor 7 in FIG. 3 . In other words, rightward displacement of the armor 7 relative to the seal pipe 8 in FIG. 3 can be prevented. Furthermore, because the engaging surface of the outer engaging projections 8b with the inner periphery of the armor 7 is an annular plane perpendicular to the axial direction, the seal pipe 8 does not move over the engaging surface and become displaced leftward in FIG. 3 , and the seal pipe 8 and the armor 7 are firmly engaged with each other. As a result, axial positional displacement of the armoring 7 relative to the seal pipe 8 is reliably prevented.

[0037] In the present embodiment, an outer engaging projection 8b that engages with the inner peripheral edge of the armor 7 is also formed on the outer peripheral edge at the other axial end of the seal pipe 8 (the left end in FIG. 1 ). Therefore, in the present embodiment, rightward positional deviation of the seal pipe 8 relative to the armor 7 can also be prevented at the left end in FIG. 1 . In other words, leftward positional deviation of the armor 7 relative to the seal pipe 8 can be prevented at the left end in FIG. 1 . That is, in the present embodiment, positional deviation of the armor 7 relative to the seal pipe 8 to both the left and right in FIG. 1 is prevented. Here again, because the engagement surface of the outer engaging projection 8b with the inner peripheral edge of the armor 7 is an annular plane perpendicular to the axial direction, the seal pipe 8 does not move over the engagement surface and shift to the right at the left end in FIG. 1 , and the seal pipe 8 and the armor 7 are firmly engaged with each other.

[0038] Next, a second embodiment will be described with reference to Fig. 4. The difference between this embodiment and the first embodiment shown in Fig. 3 described above is the shape of the engagement surface between the inner engaging projection 8a and the outer peripheral edge of the end plate 9, and the shape of the engagement surface between the outer engaging projection 8b and the inner peripheral edge of the armor ring 7. Since the other configurations are the same, the same or equivalent configurations are designated by the same reference numerals and redundant description thereof will be omitted.

[0039] In this embodiment as well, an inner engaging protrusion 8a that engages with the outer peripheral edge of the end plate 9 is formed on the inner peripheral edge at one axial end (the end on the right side in FIG. 1) of the seal pipe 8. Also, an inner engaging protrusion 8a that engages with the outer peripheral edge of the end plate 9 is formed on the inner peripheral edge at the other axial end (the end on the left side in FIG. 1) of the seal pipe 8. This makes it possible to prevent the seal pipe 8 from being displaced in the axial direction relative to the permanent magnet 6.

[0040] In this embodiment, the engagement surface of the inner engaging projection 8a with the outer peripheral edge of the end plate 9 is an annular tapered surface whose inner diameter decreases toward the axial end edge of the seal pipe 8. As described above, the seal pipe 8 is attached to the outer peripheral surface of the permanent magnet 6 by first expanding its diameter and then contracting it. By forming the tapered surface described above, the axial position of the seal pipe 8 relative to the end plate 9 is automatically guided to the correct position by the annular tapered surface when the seal pipe 8 is contracted. Furthermore, at this time, a clamping force acts on the permanent magnets 6 arranged in the axial direction from both sides, so that the permanent magnets 6 are firmly held not only in the radial direction but also in the axial direction.

[0041] Furthermore, an outer engaging protrusion 8b that engages with the inner peripheral edge of the armor ring 7 is formed on the outer peripheral edge at one axial end (the end on the right side in FIG. 1 ) of the seal pipe 8. Furthermore, an outer engaging protrusion 8b that engages with the inner peripheral edge of the armor ring 7 is also formed on the outer peripheral edge at the other axial end (the end on the left side in FIG. 1 ) of the seal pipe 8. This makes it possible to prevent the seal pipe 8 from being displaced in the axial direction relative to the armor ring 7. In other words, it is possible to prevent the armor ring 7 from being displaced in the axial direction relative to the seal pipe 8.

[0042] The engagement surface of the outer engaging projection 8b with the inner peripheral edge of the armor 7 is an annular tapered surface whose outer diameter increases toward the axial end edge of the seal pipe 8. As described above, the armor 7, i.e., the multiple divided armor rings 7a, are attached to the outer peripheral surface of the seal pipe 8 by first expanding the diameter and then contracting it. By forming the above-described annular tapered surface, the axial position of the armor ring 7 with respect to the seal pipe 8 is automatically guided to the correct position by the annular tapered surface when the armor ring 7 is contracted. Furthermore, at this time, a clamping force acts from both sides on the divided armor rings 7a lined up in the axial direction, so that the multiple divided armor rings 7a are firmly held in the axial direction.

[0043] Furthermore, the pressure of the coolant in the annular inlet flow path P2 and the annular outlet flow path P6 increases due to centrifugal force as the rotor 2 rotates. By forming the inner engaging protrusions 8a on the seal pipe 8 that engage with the outer peripheral edge of the end plate 9 as in the above embodiment, it is possible to suppress axial outward deflection of the outer peripheral edge of the end plate 9 due to the pressure of the coolant.

[0044] The rotor 2 of the rotating electric machine 1 of the above-described embodiments (first and second embodiments) includes a rotor core 5, permanent magnets 6, an armoring 7, a seal pipe 8, and end plates 9. The permanent magnets 6 are attached to the outer peripheral surface of the rotor core 5 in a circumferentially aligned arrangement. The armoring 7 is divided into multiple pieces in the axial direction of the rotor 2 and holds the permanent magnets 6 from the outside. The seal pipes 8 are sandwiched between the permanent magnets 6 and the armoring 7. A pair of end plates 9 sandwich the rotor core 5 and the permanent magnets 6 from both sides in the axial direction. Here, an inner engaging protrusion 8a that engages with the outer peripheral edge of the end plate 9 is formed on the inner peripheral edge at one axial end of the seal pipe 8. This prevents the seal pipe 8 from being misaligned in the axial direction relative to the end plate 9, i.e., relative to the permanent magnets 6.

[0045] In the above embodiment, an inner engaging projection 8a that engages with the outer peripheral edge of the end plate 9 is also formed on the inner peripheral edge at the other axial end of the seal pipe 8. In this way, it is preferable to form the inner engaging projection 8a not only at one end of the seal pipe 8 but also at the other end, that is, to form the inner engaging projection 8a at both axial ends of the seal pipe 8. In this way, it is possible to prevent misalignment of the seal pipe 8 relative to the end plate 9, i.e., relative to the permanent magnet 6, in both directions along the axial direction.

[0046] Furthermore, in the first embodiment, the engagement surface of the inner engagement projection 8 a with the outer peripheral edge of the end plate 9 is an annular plane perpendicular to the axial direction. By making the engagement surface an annular plane perpendicular to the axial direction, the seal pipe 8 and the end plate 9 are firmly engaged, and axial displacement of the seal pipe 8 relative to the permanent magnet 6 is reliably prevented.

[0047] Alternatively, in the second embodiment, the engagement surface of the inner engaging projection 8a with the outer peripheral edge of the end plate 9 is an annular tapered surface whose inner diameter decreases toward the axial end edge of the seal pipe 8. By making the engagement surface an annular tapered surface in this way, the axial position of the seal pipe 8 relative to the end plate 9 is automatically guided to the correct position by the annular tapered surface. In addition, a clamping force acts from both sides on the permanent magnets 6 arranged in the axial direction, so that the permanent magnets 6 are firmly held in the axial direction as well.

[0048] In the above embodiment, an outer engaging protrusion 8b that engages with the inner peripheral edge of the armor ring 7 is also formed on the outer peripheral edge at one axial end of the seal pipe 8. This makes it possible to prevent the seal pipe 8 from being displaced in the axial direction relative to the armor ring 7. In other words, it is possible to prevent the armor ring 7 from being displaced in the axial direction relative to the seal pipe 8.

[0049] Furthermore, in the above embodiment, an outer engaging projection 8b that engages with the inner peripheral edge of the armor ring 7 is also formed on the outer peripheral edge at the other axial end of the seal pipe 8. In this way, it is preferable to form the outer engaging projection 8b not only at one end of the seal pipe 8 but also at the other end, that is, to form the outer engaging projection 8b on both axial ends of the seal pipe 8. In this way, it is possible to prevent misalignment of the seal pipe 8 relative to the armor ring 7 in both directions along the axial direction. In other words, it is possible to prevent misalignment of the armor ring 7 relative to the seal pipe 8 in both directions along the axial direction.

[0050] Furthermore, in the first embodiment, the engagement surface of the outer engagement projection 8b with the inner peripheral edge of the armor 7 is an annular plane perpendicular to the axial direction. By making the engagement surface an annular plane perpendicular to the axial direction in this manner, the seal pipe 8 and the armor 7 are firmly engaged, thereby reliably preventing axial displacement of the seal pipe 8 relative to the armor 7. In other words, axial displacement of the armor 7 relative to the seal pipe 8 is reliably prevented.

[0051] Alternatively, in the second embodiment, the engagement surface of the outer engagement projection 8b with the inner peripheral edge of the armor ring 7 is an annular tapered surface whose outer diameter increases toward the axial end edge of the seal pipe 8. By forming the engagement surface as an annular tapered surface in this manner, the axial position of the armor ring 7 relative to the seal pipe 8 is automatically guided to the correct position by the annular tapered surface. In addition, a clamping force acts from both sides on the divided armor rings 7 that are lined up in the axial direction, so that the divided armor rings 7 are firmly held in the axial direction.

[0052] Although several embodiments have been described, modifications or variations of the embodiments can be made based on the above disclosure. All components of the above embodiments and all features described in the claims may be individually extracted and combined as long as they are not mutually contradictory. For example, although the inner engaging protrusion 8a and the outer engaging protrusion 8b are preferably formed on both ends of the seal pipe 8, they may be provided on only one of the ends. Also, the inner engaging protrusion 8a may be provided on both ends, while the outer engaging protrusion 8b may be provided on only one of the ends.

[0053] The shape of the engagement surfaces of the inner engagement protrusion 8 a and the outer engagement protrusion 8 b can also be selected appropriately. For example, the engagement surface of the inner engagement protrusion 8 a at one end may be an annular flat surface perpendicular to the axial direction, and the engagement surface of the inner engagement protrusion 8 a at the other end may be the above-mentioned annular tapered surface. Alternatively, the engagement surface of the inner engagement protrusion 8 a may be an annular flat surface perpendicular to the axial direction, and the engagement surface of the outer engagement protrusion 8 b may be the above-mentioned annular tapered surface.

[0054] Although the rotating electric machine 1 including the rotor 2 in the above embodiment is a generator, the rotor of the present disclosure can also be applied to a rotor of an electric motor that receives electric power and outputs power. That is, the rotor of the present disclosure can be applied to a rotating electric machine such as a generator or an electric motor. Furthermore, in the above embodiment, the axial flow passage P3 is formed on the radially outer surface of the permanent magnet 6, but it may be formed on the radially inner surface of the permanent magnet 6. That is, in this case, the axial flow passage P3 is formed between the rotor core 5 and the permanent magnet 6. In this case, too, the coolant flowing through the axial flow passage P3 can move from the joint between axially adjacent permanent magnets 6 to the radially outer surface of the permanent magnet 6, so the above-mentioned seal pipe 8 can still prevent the coolant from leaking to the outside of the rotor 2.

[0055] The entire contents of Japanese Patent Application No. 2023-143394 (filed September 5, 2023) are hereby incorporated by reference into this specification.

[0056] REFERENCE SIGNS LIST 1 Rotating electric machine 2 Rotor 5 Rotor core 6 Permanent magnet 7 Armoring 7a Split armoring 8 Seal tube 8a Inner engaging projection 8b Outer engaging projection 9 End plate O Rotating shaft (of rotor 2)

Claims

1. A rotor for a rotating electric machine comprising: a rotor core; a plurality of permanent magnets attached in a circumferential direction on the outer surface of the rotor core; an armature divided into several pieces in the axial direction, which is the direction of the rotation axis of the rotor, and holding the permanent magnets from the outside; a seal tube sandwiched between the permanent magnets and the armature; and a pair of end plates sandwiching the rotor core and the plurality of permanent magnets from both sides in the axial direction, wherein an inner engagement protrusion is formed on the inner peripheral edge at one axial end of the seal tube that engages with the outer peripheral edge of the end plate.

2. A rotor for a rotating electric machine as described in claim 1, wherein the inner peripheral edge at the other axial end of the seal pipe is also formed with an inner engagement protrusion that engages with the outer peripheral edge of the end plate.

3. A rotor for a rotating electric machine according to claim 1 or 2, wherein the engagement surface of the inner engagement projection with the outer circumferential edge of the end plate is an annular plane perpendicular to the axial direction.

4. A rotor for a rotating electric machine as claimed in claim 1 or 2, wherein the engagement surface of the inner engagement projection with the outer peripheral edge of the end plate is an annular tapered surface whose inner diameter decreases towards the axial end edge of the seal pipe.

5. A rotor for a rotating electric machine according to claim 1 or 2, wherein an outer peripheral edge of the seal pipe at one axial end is also formed with an outer engaging protrusion which engages with the inner peripheral edge of the armouring.

6. A rotor for a rotating electric machine as claimed in claim 5, wherein the outer peripheral edge at the other axial end of the seal pipe is also formed with an outer engagement protrusion which engages with the inner peripheral edge of the armouring.

7. A rotor for a rotating electric machine according to claim 6, wherein an engagement surface of said outer engagement projection with said inner peripheral edge of said armouring is an annular flat surface perpendicular to said axial direction.

8. A rotor for a rotating electric machine as claimed in claim 6, wherein the engagement surface of the outer engagement projection with the inner peripheral edge of the armouring is an annular tapered surface whose outer diameter increases towards the axial end edge of the seal pipe.

Images