JP2018064384A - Totally enclosed fan cooled type rotary electric machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To secure the cooling efficiency of a totally enclosed fan cooled type rotary electric machine with a simpler structure.SOLUTION: An totally enclosed fan cooled type rotary electric machine 100 includes: a rotor 10 having a rotor shaft 11 and a rotor core 12; a stator 20 having a stator core 21 and a stator coil 22; a frame 40; a coupling side bearing 32 and an anti-coupling side bearing 31; a coupling side bearing bracket 52 and an anti-coupling side bearing bracket 51; an inner fan 55 which is attached to a position between the anti-coupling side bearing 31 of the rotor shaft 11 and the rotor core 12 and drives a cooling gas; and an outer fan 56 which is attached to the outer side of the anti-coupling side bearing 31 of the rotor shaft 11. An outflow direction of the cooling gas from the inner fan 55 inclines to the radial outer side and the anti-coupling side bearing bracket 51 side.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a fully enclosed outer fan-shaped rotating electrical machine.

  The all-enclosed fan-shaped rotating electrical machine includes a rotor having a rotor shaft and a rotor core, and a stator, and the rotor core and the stator are housed in a closed space formed by a frame or the like.

  Cooling for removing heat generated in the stator and the rotor core is usually performed by circulation of a cooling gas such as air in the sealed space and forced ventilation of outside air outside the closed space.

  Specifically, an internal fan attached to the rotor shaft is provided for circulating the cooling gas in the sealed space. Further, in order to forcibly blow outside air, there are many examples in which an outside fan is provided at one end (on the opposite side) of the rotor shaft of the rotor to forcibly blow outside air (see Patent Document 1).

JP2015-95932A

  When a cooler having a cooling pipe is provided, heat transfer from the inside to the outside of the closed space is performed by heat transfer from the outer surface to the inner surface of the cooling pipe, that is, heat transfer in the cooling pipe.

  On the other hand, in the case of the fin frame system not having a cooling pipe, for example, an internal cooling gas passage extends in the frame in the axial direction and is provided at intervals in the circumferential direction. Moreover, the fin is provided in the outer surface in the area | region where the channel | path is not formed in the circumferential direction. Thus, the area of the boundary of the heat transfer between the inside and the outside of the closed space, that is, the heat transfer area is secured.

  In order to further improve the cooling capacity in the fin frame system, for example, there is a method of improving the heat transfer rate by increasing the flow velocity inside and outside the heat transfer surface. For this purpose, it is necessary to improve the capacity of the outer fan and the inner fan. Since the outer fan and the inner fan are attached to the rotor shaft, the rotational speed cannot be increased. Therefore, it is necessary to increase the diameter of the outer fan and the inner fan.

  As the number of poles decreases, the spacing between the upper and lower openings increases and the space for connecting the ends, that is, the axially outer portions of the stator core, increases. The length that the portion protrudes outward in the axial direction is increased. For this reason, the end of the stator winding is arranged on the radially outer side of the inner fan.

  In such a state, in order to increase the diameter of the inner fan, if the mounting position of the inner fan on the rotor shaft is outside the end of the stator winding, it is necessary to increase the axial length of the rotating electrical machine body. Is not preferable.

  Then, an object of this invention is to ensure the cooling efficiency of a fully-closed outside fan-shaped rotary electric machine by the simplified structure.

  In order to achieve the above-mentioned object, a fully-enclosed fan-shaped rotating electrical machine according to the present invention includes a rotor shaft that extends in the axial direction and is rotatably supported, and a cylindrical rotor that is provided on the radially outer side of the rotor shaft. A rotor having an iron core, a stator iron core provided radially outside the rotor iron core, a stator having a stator winding that passes through an inner portion of the stator iron core in the axial direction, and A frame that is disposed outside the stator in the radial direction and that houses the rotor core and the stator, and a coupling that supports the rotor shaft on both sides of the rotor shaft in the axial direction across the rotor core. A side bearing and an anti-coupling side bearing, and a coupling-side bearing bracket and an anti-coupling side bearing bracket that fixedly support the coupling-side bearing and the anti-coupling side bearing and connect to the axial end of the frame; An inner fan that is mounted at a position between the anti-coupling side bearing of the rotor shaft and the rotor core and drives a cooling gas, and is attached to the outer side in the axial direction of the anti-coupling side bearing of the rotor shaft. A coupling-side bearing bracket and an outer fan that supplies the outside air to the outer surface of the frame, and the cooling gas outflow direction from the inner fan is inclined radially outward and toward the anti-coupling-side bearing bracket. It is characterized by.

  ADVANTAGE OF THE INVENTION According to this invention, the cooling efficiency of a fully enclosed external fan-shaped rotary electric machine can be ensured with the simplified structure.

It is a longitudinal cross-sectional view which shows the structure of the fully-closed outer fan-shaped rotary electric machine which concerns on 1st Embodiment. FIG. 2 is a cross-sectional view taken along the line II-II in FIG. 1 illustrating the configuration of the fully-enclosed outer fan-shaped rotating electrical machine according to the first embodiment. It is a longitudinal cross-sectional view which shows the structure of the fully enclosed outer fan type rotary electric machine which concerns on 2nd Embodiment.

  Hereinafter, with reference to the drawings, a fully enclosed outer fan-shaped rotating electrical machine according to an embodiment of the present invention will be described. Here, the same or similar parts are denoted by common reference numerals, and redundant description is omitted.

[First Embodiment]
FIG. 1 is an elevational cross-sectional view showing the configuration of a fully closed outer fan-shaped rotating electrical machine according to the first embodiment. 2 is a cross-sectional view taken along line II-II in FIG.

  The fully-enclosed fan-shaped rotating electrical machine 100 includes a rotor 10, a stator 20, and a frame 40.

  The rotor 10 includes a rotor shaft 11 extending in the axial direction and a rotor core 12 provided on the radially outer side of the rotor shaft 11. The rotor shaft 11 has a coupling portion 11a at one end portion in the axial direction.

  The joint portion 11a is a driven portion when the fully-enclosed external fan-type rotating electrical machine 100 is an electric motor, and is a joint portion with a prime mover when the fully-closed external-fan electrical rotating machine 100 is a generator. Hereinafter, regarding the axial direction, the direction from the center in the axial direction of the fully enclosed outer sector rotating electric machine 100 toward the coupling portion 11a is referred to as a coupling side, and the opposite direction is referred to as an anti-coupling side.

  The rotor shaft 11 is rotatably supported by a coupling-side bearing 32 on the coupling side and an anti-coupling-side bearing 31 on the anti-coupling side on both sides in the axial direction across the rotor core 12. An inner fan 55 described later is provided at a position of the rotor shaft 11 between the rotor core 12 and the anti-coupling side bearing 31.

  The stator 20 is a cylindrical stator core 21 disposed with a gap on the outer side in the radial direction of the rotor core 12. The stator 20 is formed on the inner side in the circumferential direction of the stator core 21, and is spaced apart from each other in the circumferential direction. And a stator winding 22 passing through a plurality of axially extending slots (not shown).

  The frame 40 is cylindrical and is on the outer side in the radial direction of the stator core 21 and accommodates the rotor core 12 and the stator 20. Four flow passages 41 are formed in the circumferential direction of the frame 40 and extend in the axial direction at intervals. Each flow passage 41 communicates with the internal space of the frame 40 via an outlet opening 41b formed on the coupling side and an inlet opening 41a formed on the anti-coupling side. A plurality of external fins 43 are provided on the outer surface of the circumferential portion where the flow passage 41 is not formed. The external fins 43 extend in the axial direction and expand in the radial direction.

  The axial end of the cylindrical frame 40 has a coupling side bearing bracket 52 that supports the coupling side bearing 32 on the coupling side and an anti-coupling side bearing bracket that supports the anti-coupling side bearing 31 on the anti-coupling side. 51 is provided. The coupling side bearing bracket 52 and the anti-coupling side bearing bracket 51 form a closed space 40 a together with the frame 40. An inner fan 55 is provided at a position of the rotor shaft 11 between the rotor core 12 and the anti-coupling side bearing 31, and a cooling gas such as air is driven by the inner fan 55 in the closed space 40 a. Circulate.

  The inner surfaces of the coupling side bearing bracket 52 and the anti-coupling side bearing bracket 51 are guided along the flow so that the flow of the cooling gas is smooth, that is, the pressure loss due to the circulation of the cooling gas is suppressed. A curved surface with a proper shape is formed.

  An outer fan 56 is provided on the outer side in the axial direction of the anti-coupling side bearing 31 of the rotor shaft 11. An outer fan cover 56 a is provided outside the outer fan 56. The outer fan cover 56a is formed with a suction hole 56c through which the outer fan 56 sucks outside air. On the suction side of the outer fan 56, a guide 56b is provided. The outer fan 56 is a centrifugal type. Therefore, the outside air is sucked in the axial direction along the guide 56b and is pumped radially outward.

  The cooling gas pressure-fed by the outer fan 56 flows out in the axial direction along the outer surface of the frame 40 by the outer fan cover 56a. The cooling gas that has flowed out flows while cooling the outer surfaces of the outer fins 43 provided on the outer surface of the frame 40 and the radially outer portion of the flow passage 41 formed in the frame 40.

  As described above, the inner fan 55 is attached to the rotor shaft 11 at a position between the rotor core 12 and the anti-coupling side bearing 31. The inner fan 55 sucks the cooling gas from the rotor core 12 and the stator 20 side, pumps the cooling gas in the radial direction, and flows it into the inlet opening 41 a of the flow passage 41 formed in the frame 40.

  The inner fan 55 is formed such that the outflow direction from the inner fan 55 is inclined from the radially outward direction to the anti-coupling side bearing bracket 51 side. That is, the cooling gas at the outlet of the inner fan 55 is pumped in the direction of the anti-coupling side bearing bracket 51 and flows radially outward along the inner surface of the anti-coupling side bearing bracket 51, and then the plurality of inlet openings 41a. Flows into the flow passage 41 from the

  In the present embodiment thus formed, the flow velocity of the cooling gas on the inner surface side of the anti-coupling side bearing bracket 51 is increased. On the outer surface side of the anti-coupling side bearing bracket 51, outside air flows by the outside fan 56. Therefore, the flow velocity of the fluid is ensured both on the inner surface side and the outer surface side of the anti-coupling side bearing bracket 51, and the thermal conductivity between the inner surface side and the outer surface side of the anti-coupling side bearing bracket 51 increases. For this reason, in addition to the heat removal through the frame 40, the heat removal through the anti-coupling side bearing bracket 51 is reliably performed.

  As described above, the fully-enclosed fan-shaped rotating electrical machine according to the present embodiment can improve the cooling efficiency of the fully-enclosed external fan-shaped rotating electrical machine 100 with a simplified configuration without depending on a complicated configuration.

[Second Embodiment]
FIG. 3 is an elevational cross-sectional view showing a configuration of a fully enclosed outer fan-shaped rotating electrical machine according to the second embodiment. This embodiment is a modification of the first embodiment.

  In the fully-closed outer fan-shaped rotating electrical machine 100 according to the second embodiment, a plurality of inner fins 51 a are provided on the inner surface of the anti-coupling side bearing bracket 51. The inner fins 51a are provided radially in the radial direction and expand in the axial direction.

  A plurality of outer fins 51 b are provided on the outer surface of the anti-coupling side bearing bracket 51. The outer fins 51b are provided radially in the radial direction and expand in the axial direction.

  As a result, it is possible to increase the heat transfer area in the heat removal through the anti-coupling side bearing bracket 51.

  As described above, in the fully closed outer fan-shaped rotating electrical machine according to the second embodiment, the heat removal through the anti-coupling side bearing bracket 51 is further reliably performed, and the cooling efficiency of the fully-closed outer fan-shaped rotating electrical machine is further increased. Can be improved.

[Other Embodiments]
As mentioned above, although embodiment of this invention was described, embodiment is shown as an example and is not intending limiting the range of invention. For example, in the embodiment, the case of a horizontal type rotary electric machine has been described as an example, but the case of a vertical type may be used.

  Furthermore, the embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the spirit of the invention. The embodiments and the modifications thereof are included in the scope of the invention and the scope of the invention, and are also included in the invention described in the claims and the equivalents thereof.

  DESCRIPTION OF SYMBOLS 10 ... Rotor, 11 ... Rotor shaft, 11a ... Coupling part, 12 ... Rotor iron core, 20 ... Stator, 21 ... Stator iron core, 22 ... Stator winding, 31 ... Anti-coupling side bearing, 32 ... Coupling side Bearing, 40 ... Frame, 40a ... Closed space, 41 ... Flow passage, 41a ... Inlet opening, 41b ... Outlet opening, 43 ... Outer fin (fin), 51 ... Anti-coupling side bearing bracket, 51a ... Inner fin (fin), 51b, outer fins (fins), 52 ... coupling side bearing bracket, 55 ... inner fan, 56 ... outer fan, 56a ... outer fan cover, 56b ... guide, 56c ... suction hole, 100 ... fully-closed outer fan-shaped rotating electric machine

Claims (6)

A rotor shaft that extends in the axial direction and is rotatably supported, and a cylindrical rotor iron core provided radially outside the rotor shaft;
A stator core having a stator core provided on the outer side in the radial direction of the rotor core, and a stator winding penetrating the inner part of the stator core in the axial direction;
A frame that is disposed outside the stator in the radial direction and houses the rotor core and the stator;
A coupling-side bearing and an anti-coupling-side bearing that support the rotor shaft on both sides of the rotor shaft in the axial direction across the rotor core;
A coupling-side bearing bracket and an anti-coupling-side bearing bracket that fixedly support the coupling-side bearing and the anti-coupling-side bearing, respectively, and are connected to the axial ends of the frame;
An inner fan that is attached to a position between the anti-coupling side bearing of the rotor shaft and the rotor core and drives a cooling gas;
An outer fan mounted on the outer side of the anti-coupling side bearing of the rotor shaft to supply outside air to the outer surface of the anti-coupling side bearing bracket and the frame;
With
The fully-enclosed outer fan-shaped rotating electrical machine is characterized in that the cooling gas flow-out direction from the inner fan is inclined radially outward and toward the anti-coupling side bearing bracket.   The fully-enclosed outer fan-shaped rotating electrical machine according to claim 1, wherein a curved surface having a smooth shape is formed on an inner surface of the anti-coupling bearing bracket so as to guide the cooling gas.   The cooling gas driven by the inner fan flows into the frame, and axially extending flow passages are arranged in the circumferential direction so as to flow out to the opposite side of the inner fan across the stator core. The fully-enclosed outer fan-shaped rotating electrical machine according to claim 1 or 2, wherein the fully-enclosed outer fan-shaped rotating electrical machine is formed at intervals.   The rotating electrical machine according to any one of claims 1 to 3, wherein the frame further includes a plurality of fins provided on an outer surface.   The rotating electrical machine according to any one of claims 1 to 4, wherein the anti-coupling side bearing bracket has fins provided on an inner surface thereof.   The rotating electrical machine according to any one of claims 1 to 5, wherein the anti-coupling side bearing bracket has fins provided on an outer surface.

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