JP2017158398A - Rotating electric machine - Google Patents

Abstract

An object of the present invention is to efficiently cool a rotor while ensuring a sufficient member strength of the rotor. A rotating electrical machine includes a sealed casing, a rotating shaft that is rotatably supported by the casing via a bearing, a rotor that is fixed to an outer peripheral surface of the rotating shaft, and that rotates together with the rotating shaft, and a rotor And a stator fixed to the casing. The rotor includes a plurality of rotor cores formed by laminating metal plates having openings into which the rotation shafts are inserted in the axial direction of the rotation shafts, and a plurality of cores penetrating in a direction perpendicular to the rotation shafts. A first ventilation duct, and a ventilation block disposed between two adjacent rotor cores. [Selection] Figure 1

Description

  The present invention relates to a rotating electrical machine such as a generator.

  In general, a rotating electrical machine such as a generator has a stator housed in a casing and a rotor. In such a rotating electric machine, it is necessary to cool the stator and the rotor efficiently. Therefore, a method of cooling using a stirring fan provided inside the casing, a method of cooling using air flowing through a ventilation duct of a stator core or a rotor core, and the like have been proposed.

JP 2009-6687 A

  In order to improve the performance of a rotating electrical machine, it is an important issue to efficiently cool a rotor that rotates at a high speed. In a large rotating electrical machine, cooled air is used as a refrigerant, the refrigerant is pushed from one end or both ends of the rotating electrical machine, and passes through a gap between the stator and the rotor or a ventilation duct provided in the laminated core. Generally, it is returned to a heat exchanger provided in the machine or discharged to the outside. However, the rotor may not be provided with a duct due to problems with the member cost and strength of the rotor. In this case, the refrigerant that cools the rotor passes only through the rotor surface. In particular, when the refrigerant is pushed in from both sides, there is a concern that the temperature of the refrigerant rises toward the center of the rotating electrical machine.

  Accordingly, an object of the present invention is to solve the problem of efficiently cooling the rotor while sufficiently securing the member strength of the rotor.

  A rotating electrical machine according to an embodiment of the present invention includes a casing having a hermetically sealed structure, a rotating shaft that is rotatably supported by the casing via a bearing, and is fixed to an outer peripheral surface of the rotating shaft and rotates together with the rotating shaft. A rotor that faces the rotor and is fixed to the casing, and the rotor has a metal plate having an opening into which the rotation shaft is inserted. A plurality of rotor cores formed by being laminated in the axial direction, and a plurality of first ventilation ducts penetrating in a direction perpendicular to the rotation axis are provided, and between two adjacent rotor cores. And a ventilation block arranged.

  ADVANTAGE OF THE INVENTION According to this invention, a rotor can be cooled efficiently, ensuring the member intensity | strength of a rotor sufficiently.

Sectional drawing which shows the internal structure of the rotary electric machine which concerns on the 1st Embodiment of this invention. The perspective view of the ventilation block shown in FIG. The front view of the tooth | gear part in the broken-line area | region of FIG. FIG. 3 is a transparent top view showing a structure of a tooth portion in a broken line region of FIG. 2. The permeation | transmission upper surface figure which shows the connection structure of the tooth | gear part of a ventilation block and balance weight in the 2nd Embodiment of this invention. Sectional drawing which shows the internal structure of the rotary electric machine which concerns on the 3rd Embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

<First Embodiment>
FIG. 1 is a cross-sectional view showing the internal structure of the rotating electrical machine 10 according to the first embodiment of the present invention. As shown in FIG. 1, in the rotating electrical machine 10, a rotating shaft 12 is rotatably supported via a bearing 13 in a sealed casing 11.

  The rotating shaft 12 has a ventilation groove 121 on the outer peripheral surface of the shaft that extends from the outside of the rotor 14 in the axial direction to a position facing a rotor internal ventilation duct 142a described later. Further, in the present embodiment, the ventilation grooves 121 are formed at six locations at a pitch angle interval of 60 ° on the outer peripheral surface of the shaft, but the number, interval, and width of the ventilation grooves 121 are rotated. It can be appropriately changed in consideration of the strength of the shaft 12 and the ventilation efficiency.

  The rotor 14 is fixed to the outer peripheral surface of the rotating shaft 12 concentrically with the rotating shaft 12 and rotates together with the rotating shaft 12. The rotor 14 includes a rotor core 141, a ventilation block 142, a rotor bar 143, and a short-circuit ring 144.

  The rotor core 141 is formed in a hollow cylindrical shape as a whole by laminating metal plates in which an opening into which the rotating shaft 12 is inserted is laminated in the axial direction of the rotating shaft 12. The ventilation block 142 is a ring-shaped member disposed so as to be sandwiched between two adjacent rotor cores 141, and the rotation shaft 12 is inserted through the hollow portion. Inside the ventilation block 142, a plurality of in-rotor ventilation ducts 142 a that communicate the inner peripheral surface side and the outer peripheral surface side of the rotor 14 in the radial direction of the rotating shaft 12 are provided.

  2 is a perspective view of the ventilation block 142 shown in FIG. 1, FIG. 3 is a front view of the protrusion 142b in the broken line area A of FIG. 2, and FIG. 4 is a transparent view showing the internal structure of the protrusion 142b in the area A. It is a top view. As shown in FIG. 2, the ventilation block 142 has a plurality of projecting portions 142 b that are provided at a predetermined pitch angle θ and project in a direction (radial direction) orthogonal to the rotation shaft 12. In addition, the cross-sectional shape of the rotor internal ventilation duct 142a is not limited to a circle, and the cross-sectional shape of the protrusion 142b is not limited to a rectangle.

  As shown in FIGS. 3 and 4, the plurality of in-rotor ventilation ducts 142 a are provided on the end surface side of the plurality of protrusions 142 b (that is, on the outer peripheral surface side of the ventilation block 142) and the inner peripheral surface of the ventilation block 142. It is formed so as to communicate with the side. The rotor internal ventilation duct 142a is provided at a pitch angle θ with the point O as the center, and extends from the inner peripheral surface of the ventilation block 142 toward the outer peripheral surface. Furthermore, a plurality of recesses 142c into which rotor bars 143 described later are fitted are formed between the plurality of protrusions 142b.

  The rotor bar 143 is a rod-shaped member formed of a conductive material such as a copper alloy, and is fixed by being fitted into the plurality of recesses 142c. Further, the axial end portion of each rotor bar 143 protrudes outward in the axial direction from the axial end portion of the rotor core 141.

  The short-circuit ring 144 is a ring-shaped member formed of a conductive material, and is disposed on both sides of the rotor 14 in the axial direction. The short-circuit ring 144 electrically connects the rotor bars 143 protruding from the axial end of the rotor core 141.

  The stator 15 includes a ring-shaped stator core 151 formed concentrically with the rotary shaft 12 and a stator winding 152 wound around the stator core 151. The outer peripheral surface side is fixed to the upper and lower inner wall surfaces of the casing 11 so as to face the rotor 14 on the surface side. Coil ends 153 that are ends of the stator winding 152 protrude outward in the axial direction from both ends of the stator core 151.

  Further, the stator 15 is formed in a radial direction at a position corresponding to the width of the rotor internal ventilation duct 142a at a position facing the rotor internal ventilation duct 142a (first ventilation duct) in the axial direction. 15 has a stator internal ventilation duct 154 (second ventilation duct) communicating the inner peripheral surface side and the outer peripheral surface side.

  As shown in FIG. 1, the upper region Z2 and the lower region Z3 of the casing 11 include cooling fins 17 that cool the air circulating in the casing 11 and a stirring fan 18 that stirs the air in the casing 11. Is provided.

  Hereinafter, the operation of the rotating electrical machine 10 configured as described above will be described.

  When the rotating electrical machine 10 is driven, the rotor 14 rotates with the rotating shaft 12. At this time, the stirring fan 18 provided in the upper and lower regions of the casing 11 also rotates to stir the air in the casing 11. As indicated by a one-dot chain line arrow in FIG. 1, the air stirred by the stirring fan 18 arranged in the upper region Z2 flows into the central region Z1 and passes through the periphery of the coil end 153 of the stator winding 152. Thus, the stator 15 is lowered while being cooled, and is guided in the direction of the rotary shaft 12. Similarly, the air stirred by the stirring fan 18 disposed in the lower region Z3 flows into the central region Z1, passes through the coil end 153, and rises while cooling the stator 15, so that the rotating shaft Guided in 12 directions.

  Next, the air guided in the direction of the rotary shaft 12 flows in the axial direction through the ventilation groove 121 of the rotary shaft 12 and is guided to the inlet of the rotor internal ventilation duct 142a.

  Next, the air guided to the inlet of the rotor internal ventilation duct 142 a passes through the rotor internal ventilation duct 142 a, and cools the rotor iron core 141 through the ventilation block 142, while the rotor internal ventilation duct 142 a You will be guided to the exit.

  Next, the air guided to the outlet of the rotor internal ventilation duct 142a is in the direction of the gap between the rotor 14 and the stator 15 or the inlet of the stator internal ventilation duct 154 disposed opposite to the rotor internal ventilation duct 142a. Guided in the direction. The air guided in the gap direction is guided toward both ends of the rotating shaft 12 while cooling the rotor 14 and the stator 15 from the surface, and joins the circulating air. On the other hand, the air guided to the inlet of the stator internal ventilation duct 154 passes through the stator internal ventilation duct 154, and is guided from the duct outlet to the upper region Z2 and the lower region Z3, respectively.

  Next, the air guided from the outlet of the stator internal duct 154 to the upper region Z2 and the lower region Z3, respectively, is cooled by the cooling fins 17 arranged in each region, and moves toward the stirring fan 18, Stir again.

  Thus, according to the rotating electrical machine 10 according to the present embodiment, the following effects can be obtained.

(1) When the rotating electrical machine 10 is driven, the air in the casing 11 flows through the ventilation block 142 (the ventilation duct 142a in the rotor), so that the rotor 14 can be cooled from the inside.

(2) The ventilation block 142 is a member different from the rotor core 141 and the rotor core 141 itself has a ductless structure. Therefore, unlike the case where a duct is formed in the rotor core 141, the rotor 14 Can be avoided.

(3) By providing the ventilation groove 121 on the outer peripheral surface of the rotary shaft 12 and disposing the stator ventilation duct 154 having the same width as the rotor ventilation duct 142a at the center of the stator 15, A circulating flow is formed in the casing 11, and components such as the rotor 14 can be efficiently cooled.

(4) Since it is not necessary to provide a plurality of ducts in the rotor iron core 141 itself, the iron core length can be shortened, and the manufacturing cost can be reduced.

(5) Since the structure can be mounted simply by adding the ventilation block 142 between the two rotor cores 141, the mounting can be easily performed without making a significant design change.

<Second Embodiment>
Then, the rotary electric machine 10 which concerns on the 2nd Embodiment of this invention is demonstrated. In addition, since the code | symbol which is common with the code | symbol in the said 1st Embodiment shows a common object, description is abbreviate | omitted and the difference from 1st Embodiment shall be demonstrated in detail.

  FIG. 5 is a transparent top view showing a connection structure between the protruding portion 142b and the balance weight 16 in the second embodiment of the present invention. As shown in the figure, the rotor internal ventilation duct 142a has a female screw hole 142d in the vicinity of the end in the outer circumferential direction. In the present embodiment, the female screw hole portion 142d is formed in all of the plurality of protruding portions 142b, but may be formed only in a part.

  Further, the rotating electrical machine 10 according to the present embodiment includes a balance weight 16 having a male screw portion 161 formed at one end. The male screw portion 161 of the balance weight 16 is formed in a size and shape that can be screwed into the female screw hole portion 142d of the rotor internal ventilation duct 142a. The number of balance weights 16 may be equal to or less than the number of female screw hole portions 142d, and individual weights may be changed. In FIG. 5, the balance weight 16 includes a hexagonal portion, but may not include this.

  Thus, according to the rotating electrical machine 10 according to the present embodiment, in addition to the effects of the first embodiment, the male screw portion 161 of the balance weight 16 is replaced with the female screw hole portion 142d of the plurality of projecting portions 142b. By screwing into either one, a new effect that the center of gravity of the entire rotor 14 can be finely adjusted is produced.

<Third Embodiment>
Next, the rotating electrical machine 10 according to the third embodiment of the present invention will be described. In addition, since the code | symbol which is common with the code | symbol in the said 1st Embodiment shows a common object, description is abbreviate | omitted and the difference from 1st Embodiment shall be demonstrated in detail.

  FIG. 6 is a cross-sectional view showing the internal structure of the rotating electrical machine 10 according to the present embodiment. As shown in the figure, the rotating electrical machine 10 according to the present embodiment is fixed to the outer side of the rotor 14 on the outer peripheral surface of the rotating shaft 12, and the center direction of the rotor 14 is increased as the rotating shaft 12 rotates. The second embodiment is different from the first embodiment in that a stirring fan 122 for blowing air is further provided.

  Thus, according to the rotating electrical machine 10 according to the present embodiment, since the stirring fan 122 guides the air in the casing 11 into the ventilation groove 121 of the rotating shaft 12, the circulation of air is promoted, and the rotor 14. The cooling efficiency can be further increased. Further, by providing the stirring fan 122, air can be circulated in the casing 11 without providing the stirring fan 18 in the upper region Z2 and the lower region Z3.

<Modification>
In each of the embodiments described above, the number of rotor cores 141 is two, and only one ventilation block 142 is disposed between the two rotor cores 141. However, the number of rotor cores 141 is not necessarily two. The number of ventilation blocks 142 is also the same. That is, three or more rotor iron cores 141 may be provided, and the plurality of ventilation blocks 142 may be spaced from each other and disposed between different iron cores. By providing a plurality of ventilation blocks 142 inside the rotor 14, the cooling efficiency can be further improved.

  Moreover, although the rotary electric machine 10 of the said embodiment was an electric motor of the system which does not have a permanent magnet, it was shown as an example of a rotary electric machine to the last, and the ventilation block 142 is provided also in the rotary electric machine of a system with a permanent magnet. Applicable.

  As mentioned above, although several embodiment of this invention was described, these embodiment is shown as an example and is not intending limiting the range of invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

DESCRIPTION OF SYMBOLS 10 ... Rotary electric machine 11 ... Casing 12 ... Rotating shaft 121 ... Ventilation groove 122 ... Stirring fan 13 ... Bearing 14 ... Rotor 141 ... Rotor core 142 ... Ventilation block 142a ... Rotor internal ventilation duct (1st ventilation duct)
142b ... projection 142c ... concave 142d ... female screw hole 143 ... rotor bar 144 ... short circuit ring 15 ... stator 151 ... stator iron core 152 ... stator winding 153 ... coil end 154 ... ventilation duct in the stator (second Ventilation duct)
16 ... Balance weight 161 ... Male screw part 17 ... Cooling fin 18 ... Stirring fan

Claims (7)

A sealed casing;
A rotating shaft rotatably supported by the casing via a bearing;
A rotor fixed to the outer peripheral surface of the rotating shaft and rotating together with the rotating shaft;
A stator fixed to the casing opposite the rotor;
With
The rotor is
A plurality of rotor cores formed by laminating a metal plate in which an opening into which the rotating shaft is inserted is laminated in an axial direction of the rotating shaft;
A plurality of first ventilation ducts penetrating in a direction perpendicular to the rotation axis are provided, and a ventilation block disposed between two adjacent rotor cores;
A rotating electric machine comprising:   2. The rotating electrical machine according to claim 1, wherein the rotating shaft has a ventilation groove on an outer peripheral surface of the shaft that extends from the outside of the rotor to a position facing the first ventilation duct. A balance weight having a male thread at one end; and
3. The rotating electrical machine according to claim 1, wherein the first ventilation duct has a female screw hole portion that can be screwed with the male screw portion in the vicinity of an end portion in an outer peripheral direction. The ventilation block is provided at intervals of a predetermined pitch angle, and has a plurality of protrusions protruding in a direction perpendicular to the rotation axis,
The rotating electrical machine according to claim 3, wherein the female screw hole is formed in the plurality of protrusions.   5. The rotating electrical machine according to claim 1, wherein two or more ventilation blocks are provided, and are arranged between the plurality of rotor cores spaced apart from each other. .   The said stator has a 2nd ventilation duct formed in the position of the axial direction of the said rotating shaft facing the said 1st ventilation duct, and penetrated in the direction orthogonal to the said rotating shaft. The rotating electrical machine according to any one of claims 1 to 5.   The rotating electrical machine according to claim 1, further comprising a stirring fan provided on the rotating shaft.

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