JP6530170B2 - Permanent magnet embedded type rotor - Google Patents

Description

  The present invention relates to a permanent magnet embedded type rotor which can be rotatably supported by a bearing provided in a motor chamber and lubricated by lubricating oil supplied to the motor chamber.

  A screw compressor used for an air conditioner, a refrigerator, or the like is provided with such a permanent magnet embedded type rotor (hereinafter, simply referred to as a "rotor"). As described in Patent Document 1, the rotor provided in the screw compressor is rotatably supported at its both ends by a pair of bearings provided in the motorized casing. In the motorized casing, oil flow paths capable of supplying lubricating oil to respective bearings are connected, and the lubricating oil is supplied to the bearings via these oil flow paths to lubricate the bearings.

  For example, as described in Patent Document 2, a rotor provided in such an electric casing is formed by laminating a plurality of laminated plates made of a magnetic material, and having a predetermined interval in the axial direction of the rotor. An intermediate plate is interposed between the fixed plates at both axial ends of the rotor, and the fixed plates are fastened and fixed via the shaft portion inserted between the fixed plates. is there.

JP, 2011-1937, A JP 2008-99479 A

  The rotor described in Patent Document 2 is in a state in which the hole formed in the fixing plate is exposed in order to insert the rotation center axis of the rotor. Therefore, when the lubricating oil supplied into the motorized casing passes through the bearing and enters the motorized casing, the lubricating oil is introduced into the rotor from the gap between the central axis of rotation of the rotor and the hole of the fixed plate. There is a risk of intrusion. When the lubricating oil intrudes into the rotor, the lubricating oil moves radially outward in the rotor due to the centrifugal force accompanying the rotation of the rotor, the rotor becomes unbalanced, and there is a possibility that the rotor vibrates when the rotor rotates. It occurs.

  In view of the above-described circumstances, at least one embodiment of the present invention is a permanent magnet embedded type rotor capable of suppressing the possibility of lubricating oil entering the rotor and the rotor becoming unbalanced and the rotor vibrating when the rotor rotates. Intended to be provided.

A permanent magnet embedded type rotor according to at least one embodiment of the present invention is
A permanent magnet embedded type rotor which can be rotatably supported by a bearing provided in a motor chamber and supplied with lubricating oil, comprising:
A plurality of rotor laminates made of magnetic material are laminated, and the plurality of rotor laminates are fixed by laminate plate sandwiching plates and fixing plates provided in order from the inner side to the outer side of both axial direction end portions to embed permanent magnets inside. The rotor body,
And a rotation center shaft which is disposed coaxially with the rotation center axis of the rotor body portion and which is rotatable through the rotor body portion integrally with the rotor body portion.
A hole for inserting the central axis of rotation is formed in the laminated plate sandwiching plate and the fixed plate,
The laminated plate is inserted into and attached to a central axis of rotation extending from the sandwiching plate and the fixed plate, and covers the hole of the fixed plate and the insertion hole through which the central axis of rotation is inserted. A rotor cover having a contact side surface portion,
An external thread surface of the rotor cover which is screwed and mounted on the rotation center shaft extending from the rotor cover and which is screwed on the rotation center shaft, and the rotor cover radially outside the insertion hole portion of the rotor cover A rotor fixing portion having a fixed side portion contacting with the
The hole portion of the fixing plate is closed by the rotor cover, and the hole portion of the fixing plate is configured to be disconnected from the outside .

  According to the permanent magnet embedded rotor, the cover side surface portion of the rotor cover is in contact with the outer surface radially outward of the hole portion of the fixing plate, and the rotor fixing portion rotates from the axial end portion of the rotor main portion The fixed side surface portion contacts with the outer surface of the rotor cover which is screwed to the central shaft and which is radially outer than the insertion hole portion of the rotor cover. For this reason, when the rotor fixing portion is screwed to the rotation center shaft and the rotor cover is fastened and fixed to the fixing plate, the outer side surface of the fixing plate on the radially outer side contacts the cover side surface portion of the rotor cover. Also, the fixed side surface portion of the rotor fixing portion contacts the outer side surface of the rotor cover. Further, the hole portion of the fixing plate is closed by the rotor cover, and the insertion hole portion of the rotor cover is closed by screwing with the flat portion of the rotor fixing portion and the rotation center axis. For this reason, communication with the exterior is interrupted | blocked and the hole of a stationary plate can prevent a possibility that lubricating oil may penetrate | invade in a rotor main-body part. Therefore, the lubricant embedded in the rotor main body causes the rotor main body to be unbalanced, and a permanent magnet embedded rotor can be realized which can suppress the possibility of the rotor main body vibrating when the rotor main body rotates.

Further, the permanent magnet embedded type rotor according to at least one embodiment of the present invention is
A permanent magnet embedded type rotor which can be rotatably supported by a bearing provided in a motor chamber and supplied with lubricating oil, comprising:
A plurality of rotor laminates made of magnetic material are laminated, and the plurality of rotor laminates are fixed by laminate plate sandwiching plates and fixing plates provided in order from the inner side to the outer side of both axial direction end portions to embed permanent magnets inside. The rotor body,
And a rotation center shaft which is disposed coaxially with the rotation center axis of the rotor body portion and which is rotatable through the rotor body portion integrally with the rotor body portion.
A hole for inserting the central axis of rotation is formed in the laminated plate sandwiching plate and the fixed plate,
The inner diameter of the hole portion of the fixing plate is larger than the inner diameter of the hole portion of the laminated plate sandwiching plate,
The laminated plate is attached to the sandwiching plate and a rotation center shaft extending from the fixed plate, the outer peripheral edge portion is disposed close to the inner surface of the hole of the fixed plate, and the inner side surface contacts the outer side surface of the laminated plate sandwiching plate The flange portion is configured such that the outer side surface is in contact with the inner surface of the annular step portion formed on the outer peripheral surface of the rotation center shaft.

  According to the permanent magnet embedded type rotor, the outer peripheral edge portion of the flange portion is disposed close to the inner surface of the hole portion of the fixed plate, the inner side surface of the flange portion contacts the outer surface of the laminated plate sandwiching plate, and the outer side of the flange portion The side surface contacts the inner surface of the annular step portion formed on the outer peripheral surface of the rotation center axis. For this reason, communication with the exterior is interrupted | blocked and the hole of a stationary plate can prevent a possibility that lubricating oil may penetrate | invade in a rotor main-body part. Therefore, the lubricant embedded in the rotor main body causes the rotor main body to be unbalanced, and a permanent magnet embedded rotor can be realized which can suppress the possibility of the rotor main body vibrating when the rotor main body rotates.

Also, in some embodiments,
An intermediate plate is interposed in the rotor body at a predetermined interval in the axial direction,
The rotor laminate is
The rotor is formed in a circular shape, and a plurality of slots for embedding the permanent magnet are formed along the peripheral edge on the inner side of the peripheral edge of the rotor laminate, and the rotor is interposed between a pair of slots adjacent in the circumferential direction. Forming a through hole in close proximity to the peripheral edge of the laminate;
The intermediate plate is
A plurality of slots are formed along the peripheral edge on the inner side of the peripheral edge of the intermediate plate, and are formed radially outward at the peripheral edge between a pair of slots adjacent in the circumferential direction of the intermediate plate. Form a notched hole where the
The notch hole portion is configured to communicate with the hole portion formed in the rotor laminated plate in contact with both surfaces of the intermediate plate in which the notch hole portion is formed.

  In this case, since the notch hole portion communicates with the hole portion formed in the rotor laminated plate contacting the both surfaces of the intermediate plate in which the notch hole portion is formed, the lubricating oil intrudes into the rotor main body portion In this case, the lubricating oil moves radially outward through the gap between the rotor laminates of the rotor main body by the centrifugal force accompanying the rotation of the rotor main body, but holes are formed in the peripheral part of the rotor laminate. Also, the hole communicates with a notch formed in the intermediate plate. For this reason, the lubricating oil moved radially outward of the rotor main body portion is discharged to the outside through the notch portion after being moved into the hole portion by the centrifugal force. Therefore, even when the lubricating oil intrudes into the rotor main body, the lubricating oil can be reliably discharged to the outside. Therefore, it is possible to realize a permanent magnet embedded type rotor that can suppress the possibility that the lubricating oil is retained in the rotor and the rotor becomes unbalanced and vibrates.

  According to at least some embodiments of the present invention, it is possible to provide a permanent magnet embedded rotor that can suppress the possibility of lubricating oil entering the rotor and the rotor becoming unbalanced and the rotor vibrating when the rotor rotates. With the goal.

It is a sectional view in plane view of a screw compressor provided with a permanent magnet embedded type rotor concerning one embodiment of the present invention. It is a sectional view of a permanent magnet embedded type rotor. It is an exploded perspective view of a permanent magnet embedded type rotor. It is a side view of a rotor lamination board which constitutes a part of permanent magnet embedded type rotor. It is a side view of the middle board which constitutes a part of permanent magnet embedded type rotor. It is a side view of a laminated board pinching plate which constitutes a part of permanent magnet embedded type rotor. It is a side view of the fixed board which constitutes a part of permanent magnet embedded type rotor. It is the A section enlarged view of a permanent magnet embedded type rotor shown in FIG. It is a side view of a rotor cover of a permanent magnet embedded type rotor.

  Hereinafter, an embodiment in which the present invention is shown in the drawings will be described in detail with reference to FIGS. 1 to 9. However, the dimensions, materials, shapes, relative arrangements, and the like of the components described in this embodiment are not intended to limit the scope of the present invention thereto alone, unless otherwise specified.

  First, before describing the embodiment of the permanent magnet embedded rotor according to the present invention, the screw compressor including the permanent magnet embedded rotor will be outlined. FIG. 1 shows a cross-sectional view of the screw compressor in a plan view. In the screw compressor, as shown in FIG. 1, a low stage compressor 10, a high stage compressor 20, and a motor 30 are arranged in series, and these devices are connected in series to a single rotor shaft (male rotor shaft 16, 24) and a central axis of rotation 60. The low-stage compressor 10 has a pair of male and female screw rotors 11 and 12 arranged in parallel, and is rotatably accommodated in the low-stage rotor casing 13 in a mutually meshed state. A low stage inlet casing 15 is disposed between the low stage rotor casing 13 and the sealed motor casing 31 of the motor 30. A pair of male and female screw rotors 21 and 22 are arranged in parallel in the high-stage compressor 20, and these screw rotors 21 and 22 are rotatably accommodated in the high-stage rotor casing 23 in a mutually meshed state.

  The screw rotors 11 and 12 of the low-stage compressor 10 are disposed in the left-right direction, and the screw rotors 21 and 22 of the high-stage compressor 20 are disposed in the vertical direction. The male rotor shaft 16 of the low stage pressure screw rotor 11 and the male rotor shaft 24 of the high stage pressure screw rotor 21 are separately configured, and are integrally rotatably coupled by a coupling 26. The male rotor shaft 16 of the low-stage compressor 10 is integrally and rotatably coupled to a rotation center shaft 60 of the motor 30 via a coupling 35.

  The motor 30 has a closed motor casing 31, and the closed motor casing 31 is connected to the lower stage inlet casing 15 so that the inside is airtight. The motor 30 includes a permanent magnet embedded rotor 40 (hereinafter simply referred to as the “rotor 40”) rotatably supported in the sealed motor casing 31, although the details will be described later. The rotor 40 is a so-called IPM motor in which permanent magnets are embedded in the rotor main body 41 (motor rotor). In the closed motor casing 31, a plurality of cooling water channels 31a are formed in the circumferential direction. Cooling water is circulated in the cooling water passage 31 a, and is cooled from the outside of the sealed motor casing 31 by the cooling water.

  The compressor side end of the rotation center shaft 60 provided in the motor 30 is rotatably supported via a bearing 36 mounted in the hermetic motor casing 31. Lubricant oil o is supplied to the inside of the bearing 36 from an oil passage 31 c formed in a bearing portion 36 d in the sealed motor casing 31. The motor end side end of the rotation center shaft 60 of the motor 30 is rotatably supported via a bearing 38 mounted in the sealed motor casing 31. The lubricating oil o is supplied to the inside of the bearing 38 from the oil passage 31b.

  In the single-machine oil-cooled two-stage screw compressor 1, the gas refrigerant is first compressed by the low-stage compressor 10 and then compressed to a higher pressure by the high-stage compressor 20.

  Next, the permanent magnet embedded type rotor 40 will be described with reference to FIGS. 2 is a cross-sectional view of the rotor 40, and FIG. 3 is an exploded perspective view of the rotor 40. As shown in FIG. As shown in FIGS. 2 and 3, the rotor 40 includes a rotor body 41, a rotation center shaft 60, and a rotor fixing portion 70 for fixing the rotor body 41 to the rotation center shaft 60. The rotor main body 41 is formed by laminating a plurality of rotor laminates 42 made of a magnetic material, and interposing an intermediate plate 45 with a predetermined interval in the rotor axial direction between the plurality of rotor laminates 42 laminated, The permanent magnets 53 are embedded in the plurality of rotor laminated plates 42 and the intermediate plates 45 by the laminated plate sandwiching plates 46 and the fixed plates 47 and the fastening portions 51 provided at both axial direction end portions.

  The rotor main body 41 is formed in a cylindrical shape, and a communication hole 41 a through which the rotation center shaft 60 can be inserted is formed at the center of the rotor main body 41. FIG. 4 is a side view of the rotor laminate plate 42. As shown in FIG. 4, the rotor laminate plate 42 is formed in a disk shape, and is formed by, for example, pressing an electromagnetic steel plate such as a silicon steel plate about 0.35 to 0.5 mm. At a central portion of the rotor laminated plate 42, a hole 42a is formed through which the rotation center shaft 60 (see FIG. 2) is inserted. The hole portion 42 a is formed in a long hole shape, and integrally connects the rotor laminated plate 42 and the rotation center shaft 60 with respect to the rotation direction of the rotation center shaft 60.

  A plurality of slots 42 b for inserting the permanent magnets 53 (see FIG. 3) are formed along the peripheral edge inside the peripheral edge of the rotor laminate plate 42. The slots 42b extend in a direction intersecting the other circumferentially adjacent slots 42b, and the circumferentially adjacent pair of slots 42b are concave (or V-shaped) radially outward of the rotor laminate plate 42. It is formed to extend. Further, at both end portions of a pair of slots 42b adjacent in the circumferential direction of the rotor laminate plate 42, through holes 42c are formed to be close to the peripheral edge of the rotor laminate plate 42 and in communication with the slots 42b. The through holes 42 c are formed substantially in a triangular shape when viewed in the central axis direction of the rotor laminated plate 42, and are formed symmetrically with respect to an imaginary line k extending in the radial direction of the rotor laminated plate 42. .

  Further, a plurality of fixing holes 42d penetrating at a predetermined interval in the circumferential direction are provided in the peripheral portion of the rotor laminated plate 42. Bolts 51a for integrally fixing the plurality of laminated rotor laminated plates 42 are inserted into the fixing holes 42d (see FIG. 2). Therefore, when the rotor 40 rotates, the peripheral portion can be firmly fixed against the centrifugal force acting on the peripheral portion of the rotor laminate plate 42 radially outside the slot 42 b.

  As shown in FIG. 5 (side view), the intermediate plate 45 is configured substantially the same as the rotor laminated plate 42. For this reason, the intermediate plate 45 demonstrates the part different from the rotor laminated plate 42, attaches | subjects the code | symbol same about the aspect same as the rotor laminated plate 42, and abbreviate | omits the description. The intermediate plate 45 has substantially the same external dimensions as the rotor laminated plate 42. Between the pair of slots 42b adjacent in the circumferential direction of the peripheral portion of the intermediate plate 45, there is no through hole portion 42c (see FIG. 4) described above, and a notch hole portion 45a is provided. The notch hole 45a is formed such that the radially outer end is open. The notch hole 45a has a size communicating with the through hole 42c (see FIG. 4) formed in the rotor laminated plate 42 in contact with both surfaces of the intermediate plate 45 in which the notch hole 45a is formed. ing. The notch hole portion 45a opens in the outer peripheral surface of the rotor main body portion 41 in a state where the rotor laminated plate 42 and the intermediate plate 45 are laminated (see FIG. 3).

  As shown in FIG. 6 (side view), the laminated plate sandwiching plates 46 and 46 'have substantially the same configuration as the intermediate plate 45 described above, so only the points different from the intermediate plate 45 will be described, The same parts as those of the intermediate plate 45 are given the same reference numerals and the description thereof is omitted. The laminated sandwiching plates 46, 46 ′ have substantially the same external dimensions as the intermediate plate 45. In the circumferential direction of the peripheral portion of the laminated plate sandwiching plate 46, 46 ', the notch hole portion 45a provided by the intermediate plate 45 is not provided. The thickness of the laminated plate sandwiching plate 46, 46 'is a thickness (for example, 3 mm) having a strength necessary to sandwich and fix the motor rotor consisting of the rotor laminated plate 42 and the intermediate plate 45 from both sides. There is.

  The fixing plate 47 is formed in an annular shape as shown in FIG. 7 (side view). The outer peripheral edge of the fixing plate 47 is located on the inner diameter side of the outer peripheral edge of the laminated plate sandwiching plate 46, and is located radially outward of the fixing hole 42d. At a central portion of the fixing plate 47, a hole 47a for inserting the rotation center shaft 60 is formed. The inner diameter of the hole 47a is larger than the outer diameter of the rotor shaft 60a of the rotation center shaft 60 and is provided with a plurality of rotor laminates 42 and the middle plate 45, as shown in FIG. It has a dimension so that it may be located inside fixed hole 42d 'formed in the innermost among fixed holes 42d. For this reason, the rotation center shaft 60 can be easily inserted into the fixing plate 47. The hole 47a of the fixing plate 47 is not limited to a circular shape, and may be any shape such as a square, a rectangle, or a polygon as long as the rotation center shaft 60 can be inserted. A plurality of fixing holes 47 b are formed on the peripheral edge of the fixing plate 47 at predetermined intervals in the circumferential direction.

  The rotor lamination plate 42, the intermediate plate 45, the lamination plate sandwiching plates 46 and 46 ', and the fixing plates 47 and 47' constituting the rotor main body 41 are disposed at both axial ends of the rotor main body 41, as shown in FIG. It is integrally fixed by the fastening part 51 which penetrates and fastens between a pair of fixed plates 47 and 47 'arrange | positioned. The fastening portion 51 includes a bolt 51 a penetrating the rotor main body 41 and a nut 51 b screwed to the tip of the bolt 51 a. The fastening portion 51 may be configured by a shaft portion provided with a male screw portion at both ends thereof and nuts 51 screwed to both ends of the shaft portion. The shaft portion 51a1 of the bolt 51a is a fixing hole 47b, 47b 'of the fixing plate 47 disposed on one end side in the axial direction of the rotor main body 41, a fixing hole 42d, 42d' and an intermediate plate 45 of the rotor laminated plate 42, a laminated plate The fixing holes 42 d and 42 d ′ of the sandwiching plates 46 and 46 ′ and the fixing holes 47 b and 47 b ′ of the fixing plate 47 ′ disposed on the other axial end side of the rotor main body 41 are inserted.

  The rotation center shaft 60 is formed stepwise in the axial direction, and the compressor side shaft 60j for determining the rotor position, the rotor shaft 60a for supporting the rotor main body 41, and the rotor shaft 60a extend from one end side of the rotor shaft 60a. Shafts 60f and 60b having a diameter smaller than that of the shaft 60a, a motor end shaft 60c extending from one end of the shaft 60b and having a diameter smaller than the shaft 60b, and a compressor-side shaft on the other end of the rotor shaft 60a. A bearing mounting shaft portion 60h and a shaft portion 60d are provided which extend from the portion 60j and have a diameter smaller than that of the compressor side shaft portion 60j.

  The motor end shaft portion 60c and the bearing mounting shaft portion 60h are supported by the bearings 38, 36 (see FIG. 1), and the rotor main body portion 41 is rotatable in a state of supporting both ends. At the outer peripheral edge on one end side of the rotor shaft 60a, when the rotor shaft 60a is viewed from the axial direction, a part of the outer peripheral edge is cut at the position on one side and the other with the axis at the center A pair of flat portions 60e extending in the axial direction is formed. The rotor laminated plate 42, the intermediate plate 45, and the holes 42a of the laminated plate sandwiching plates 46 and 46 'are passed through the rotor shaft 60a in which the flat portion 60e is formed. The rotor lamination plate 42, the intermediate plate 45, and the lamination plate sandwiching plates 46 and 46 'are fixed. As a method of fixing the rotor laminated plate 42 and the intermediate plate 45 to the rotor shaft portion 60a, a keying method may be adopted.

It is done. The rotor cover 65 and the rotor fixing portion 70 are inserted into the male screw portion 60i, so that the rotor main body 41 is fixed in the axial direction of the rotation center shaft 60, and lubricating oil is prevented from entering the rotor main body 41 Do.

  As shown in FIG. 9 (side view), the rotor cover 65 has a plate shape and is formed in an annular shape in a side view. In the central portion of the rotor cover 65, an insertion hole 65a through which the rotation center shaft 60 extending from the axial end of the rotor main body 41 can be inserted is formed. The inner diameter of the insertion hole portion 65a has a dimension in which the outer diameter of the shaft portion 60f is inserted, as shown in FIG. 8 (a partially enlarged view). Further, the outer diameter of the rotor cover 65 has a dimension that does not interfere with the innermost fastening portion 51 of the plurality of fastening portions 51, and the outer diameter is smaller than the hole 47a of the fixing plate 47. It has large dimensions. Therefore, the inner surface of the rotor cover 65 (hereinafter referred to as “cover side surface portion 65 b”) contacts the outer surface 47 c of the fixing plate 47 which is radially outward of the hole 47 a of the fixing plate 47. Therefore, the lubricating oil can be prevented from entering from between the outer side surface 47 c of the fixing plate 47 and the cover side surface portion 65 b of the rotor cover 65.

  The rotor fixing portion 70 is formed in a disk shape, and has a fixed main body portion 71 formed with a female screw portion 71a that can be screwed to the male screw portion 60i of the rotation center shaft 60 at the central portion, and the other axial end of the fixed main body portion 71 And an annular flange portion 72 projecting radially outward. The outer diameter of the flange portion 72 is smaller than the outer diameter of the rotor cover 65, and has an inner diameter dimension that the outer diameter of the shaft portion 60f enters. An inner side surface of the flange portion 72 (hereinafter, referred to as “fixed side surface portion 72 a”) extends in a direction orthogonal to the axial center direction of the rotor fixing portion 70 and contacts the outer surface 65 c of the rotor cover 65. Further, inside the central portion of the fixed main body portion 71, a female screw portion 71a which can be screwed to the male screw portion 60i of the rotation center shaft 60 is formed.

  Therefore, the lubricating oil can be prevented from entering from between the outer surface 65 c of the rotor cover 65 and the inner surface of the flange portion 72. Further, since the fixed main body portion 71 and the flange portion 72 of the rotor fixing portion 70 are screwed into the male screw portion 60i of the rotation center shaft 60, the rotor cover is viewed from the portion where the rotor fixing portion 70 and the rotation center shaft 60 are screwed together. It is possible to effectively suppress the possibility that the lubricating oil may intrude into the side of the insertion hole 65a of 65.

  In the present embodiment, as shown in FIG. 2, on the compressor side, a fixing plate 47 ′ is installed on the outside of the laminated plate sandwiching plate 46 ′ on the other end side of the rotor main body 41. A flange portion 72 'which can be inserted into the rotor shaft portion 60a having a flat portion 60e formed in an inner diameter portion is disposed, and each is in close contact with the outer surface of the laminated plate sandwiching plate 46'. The outer diameter of the flange portion 72 'is set such that the gap between the hole portion of the fixing plate 47' and the outer diameter of the flange portion 72 'is as small as possible. For this reason, lubricating oil is prevented from intruding into the rotor main body 41.

  The flange portion 72 'contacts the step portion 60g formed at the compressor-side shaft portion 60j side end of the other end of the flat portion 60e and is axially positioned. In addition, when the rotor fixing portion 70 is screwed to the rotor shaft portion 60a with the rotation center shaft 60 extending from one end side of the rotor body portion 41 inserted into the rotor shaft portion 60a, the rotor body portion 41 is at the other end in the axial direction And the cover side surface portion 65b of the inner side of the rotor cover 65 is in close contact with the outer side surface 47c of the fixing plate 47, and the cover side surface portion of the rotor cover 65 disposed on one axial end side of the rotor main body 41 The rotor main body portion 41 is fixed to the rotation center shaft 60 in a state where the 65 b is in close contact with the outer side surface 47 c of the fixing plate 47.

  As described above, in the permanent magnet embedded rotor 40 according to the present embodiment, as shown in FIG. 8, the cover side surface portion 65 b on the inner side of the rotor cover 65 is in contact with the outer surface radially outward of the hole 47 a of the fixing plate 47. The fixed side surface 72 a of the flange 72 of the rotor fixing portion 70 is in contact with the outer side surface 65 c of the rotor cover 65. For this reason, there is no possibility that lubricating oil may intrude between the fixed plate 47 and the rotor cover 65 and between the rotor cover 65 and the flange portion 72 of the rotor fixed portion 70. Further, since the rotor fixing portion 70 is screwed to the rotation center shaft 60, the lubricating oil is directed to the hole 47a side of the fixing plate 47 from the portion where the rotor fixing portion 70 and the rotation center shaft 60 are screwing together. There is no risk of intrusion. Accordingly, the communication between the hole 47a of the fixing plate 47 and the outside is blocked, and the possibility that the lubricating oil intrudes into the rotor main body 41 from the hole 47a of the fixing plate 47 can be prevented. Further, on the compressor side, by reducing the gap between the inner diameter of the hole portion 47a of the fixed plate 47 'and the outer diameter of the flange portion 72', it is possible to reduce the amount of lubricating oil entering. Therefore, the lubricating oil is retained in the rotor 40, and the rotor 40 becomes unbalanced, and it is possible to suppress the possibility of occurrence of vibration when the rotor rotates.

  Further, as shown in FIG. 3, in the rotor 40 of the present embodiment, the intermediate plate 45 is provided with the notch hole 45 a, and the notch hole 45 a is formed on the rotor laminate plate 42 in contact with both surfaces of the intermediate plate 45. Since the communication is made with the formed through hole 42c (see FIG. 4), when the lubricating oil intrudes into the rotor main body 41, the lubricating oil becomes the rotor main body by the centrifugal force accompanying the rotation of the rotor main body 41. The rotor laminate plate 42 is moved radially outward through the gap between the rotor laminate plates 42 or between the rotor laminate plate 42 and the intermediate plate 45, but a through hole 42c is formed in the peripheral portion of the rotor laminate plate 42. The hole 42 c communicates with the notch hole 45 a of the intermediate plate 45. For this reason, the lubricating oil moved to the radially outer side of the rotor main body 41 is moved into the through hole 42c by the centrifugal force and then discharged to the outside through the notch hole 45a. Therefore, even when the lubricating oil intrudes into the rotor main body 41, the lubricating oil can be reliably discharged to the outside. Accordingly, the lubricant embedded in the rotor 40 causes the rotor 40 to be unbalanced, and thus the permanent magnet embedded rotor 40 capable of suppressing the possibility of the rotor 140 vibrating when the rotor 40 rotates can be realized.

DESCRIPTION OF SYMBOLS 1 screw compressor 10 low stage compressor 11, 12, 21, 22 screw rotor 13 low stage rotor casing 15 low stage inlet casing 16, 24 male rotor shaft 20 high stage compressor 23 high stage rotor casing 26, 35 coupling Reference Signs List 30 motor 31 sealed motor casing 31a cooling water passage 31b, 31c oil passage 31d bearing portion 36, 38 bearing 37 casing 40 permanent magnet embedded rotor 41 rotor main body portion 41a communicating hole portion 42 rotor laminated plate 42a, 47a hole portion 42b slot 42c penetrating Holes 42d, 42d ', 47b, 47b' Fixing holes 45 Intermediate plates 45a Notched holes 47, 47 'Fixing plates 47c, 65c Outer surface 51 Fastening portion 51a Bolt 51b Nut 51c Shaft portion 53 Permanent magnet 60 Rotation center shaft 60a Rotor shaft 60b 60d, 60f Shaft 60c Motor end shaft 60e Flat 60g Step 60h Bearing mounting shaft 46, 46 'Laminated plate sandwiching plate 60i Male thread 60j Compressor side shaft 65 Rotor cover 65a Insertion hole 65b Cover side Part 70 Rotor fixing part 71 Fixed main body part 71a, 72b Female screw part 72 Flange part 72a Fixed side part o Lubricating oil

Claims (5)

A permanent magnet embedded type rotor which can be rotatably supported by a bearing provided in a motor chamber and supplied with lubricating oil, comprising:
A plurality of rotor laminates made of magnetic material are laminated, and the plurality of rotor laminates are fixed by laminate plate sandwiching plates and fixing plates provided in order from the inner side to the outer side of both axial direction end portions to embed permanent magnets inside. The rotor body,
And a rotation center shaft which is disposed coaxially with the rotation center axis of the rotor body portion and which is rotatable through the rotor body portion integrally with the rotor body portion.
A hole for inserting the central axis of rotation is formed in the laminated plate sandwiching plate and the fixed plate,
The laminated plate is inserted into and attached to a central axis of rotation extending from the sandwiching plate and the fixed plate, and covers the hole of the fixed plate and the insertion hole through which the central axis of rotation is inserted. A rotor cover having a contact side surface portion,
An external thread surface of the rotor cover which is screwed and mounted on the rotation center shaft extending from the rotor cover and which is screwed on the rotation center shaft, and the rotor cover radially outside the insertion hole portion of the rotor cover A rotor fixing portion having a fixed side portion contacting with the
The hole portion of the fixed plate is closed by the rotor cover, and the hole portion of the fixed plate is configured to be shut off from communication with the outside. A hole for inserting the central axis of rotation is formed in the laminated plate sandwiching plate and the fixed plate,
The inner diameter of the hole portion of the fixing plate is larger than the inner diameter of the hole portion of the laminated plate sandwiching plate,
The laminated plate is attached to the first end side of the rotation center shaft extending from the sandwiching plate and the fixed plate, the outer peripheral edge portion is disposed close to the inner surface of the hole of the fixed plate, and the inner side is the laminated plate sandwiching plate The permanent magnet according to claim 1, further comprising: a first flange portion in contact with the outer surface of the ring, the outer surface being in contact with the inner surface of the annular step portion formed on the outer peripheral surface of the rotation center shaft. Magnet embedded rotor. It is mounted on the second end of the laminated central plate and the second end opposite to the first end of the central axis of rotation extending from the fixed plate, and the inner peripheral edge contacts the outer surface of the central axis of rotation, It further comprises a second flange portion that contacts the rotor cover at the radially outer side of the inner peripheral edge portion,
The permanent magnet embedded type rotor according to claim 1 or 2 , wherein the rotor cover contacts the fixing plate on the outer peripheral side of the second flange portion. A fixing main body for fixing the rotor cover to the fixing plate via the second flange;
The permanent magnet embedded type rotor according to claim 3 , wherein the second flange portion contacts the rotor cover on an outer peripheral side of the fixed main body portion. An intermediate plate is interposed in the rotor body at a predetermined interval in the axial direction,
The rotor laminate is
The rotor is formed in a circular shape, and a plurality of slots for embedding the permanent magnet are formed along the peripheral edge on the inner side of the peripheral edge of the rotor laminate, and the rotor is interposed between a pair of slots adjacent in the circumferential direction. Forming a through hole in close proximity to the peripheral edge of the laminate;
The intermediate plate is
A plurality of slots are formed along the peripheral edge on the inner side of the peripheral edge of the intermediate plate, and are formed radially outward at the peripheral edge between a pair of slots adjacent in the circumferential direction of the intermediate plate. Form a notched hole where the
The said notch hole part is in communication with the said hole part formed in the rotor laminated plate which contacts the both surfaces of the intermediate plate in which this notch hole part was formed. A permanent magnet embedded type rotor according to any one of the preceding claims.

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