JP6069029B2 - Rotating electric machine - Google Patents

Description

  Embodiments described herein relate generally to a rotating electrical machine.

Conventionally, in a rotating electrical machine such as an electric motor or a generator, a stator and a rotor are provided inside a housing, a rotating shaft projects outside the housing, and a fan is attached to the projecting portion of the rotating shaft. A fully-enclosed external fan attached by means of is provided.
In this case, it is conceivable that water enters from the outside into the inside through a portion where the mounting portion of the fan and the protruding portion of the rotating shaft come into contact. In particular, this is likely to occur when the entire rotating electrical machine is installed and used in a vertical axis state in which the rotation axis is directed vertically.

As described above, when water enters from the outside to the inside, the lubricant applied between the rotating shaft and the bearing that supports the shaft deteriorates, causing problems such as rusting and further burning of the bearing. .
As a countermeasure, in addition to a fan guard having air permeability (water permeability), a cap-shaped cover is further provided outside the fan (see, for example, Patent Document 1).

JP-A-5-3644

However, in the case where the cap-shaped cover is provided outside the fan as described above, the air permeability by the fan is impaired and the cooling performance of the rotating electrical machine is lowered. In addition, the product cost increases.
Furthermore, for example, when a pump is coupled as a rotational load to the rotating electrical machine, an impeller is fitted to the rotating shaft and attached with a nut, but the rotating shaft is constrained so that the rotating shaft does not rotate together. In the end, it is impossible to do so, so that the cover cannot be provided, and there is a problem due to water immersion from the outside through the portion where the mounting portion of the fan and the protruding portion of the rotating shaft are in contact with each other. There are restrictions such as inviting or providing a cover after the pump is connected.

  Therefore, it is possible to prevent water from entering through the portion where the fan mounting portion and the projecting portion of the rotating shaft come into contact without requiring a conventional cap-shaped cover, and the rotating shaft is also restrained by the cap-shaped cover. Provided is a rotating electrical machine that can be performed regardless of the situation.

The rotating electrical machine according to the present embodiment has a stator and a rotor inside the housing, the rotating shaft projects outside the housing, and a fan is attached to the projecting portion of the rotating shaft by the mounting portion. The fan mounting portion is provided with a cover portion that faces the contact portion between the mounting portion and the projecting portion of the rotating shaft so as to cover the projecting portion end surface of the rotating shaft from the contacting portion in a water-tight manner. Further, an engaged portion for engaging a tool that restrains rotation of the rotating shaft is provided.

Enlarged longitudinal sectional view of the main part showing the first embodiment Full side view The top view (a) of a part in the principal part which shows 2nd Embodiment, and FIG. 1 equivalent figure (b) FIG. 3 equivalent view showing the third embodiment

The first embodiment will be described below with reference to FIGS. 1 and 2.
First, FIG. 2 shows the overall configuration of the rotating electrical machine, and a stator 2 is provided on the inner periphery of the frame 1. The stator 2 includes an iron core (stator iron core) 2a and windings (stator winding) 2b installed on the iron core 2a.
A rotor 3 is disposed inside the stator 2, and the rotor 3 includes an iron core (rotor iron core) 3a and a winding provided on the iron core 3a, particularly in this case a squirrel-cage winding. (Rotor winding) 3b.

At the center of the rotor 3, a rotating shaft 4 is inserted in the axial direction (in the drawing, the whole rotating electric machine is shown in the vertical axis state in the vertical direction).
Brackets 5 and 6 are coupled to both ends of the frame 1 in the axial direction by a plurality of bolts 7 and 8 and nuts 9 and 10, respectively. Both ends 4 a and 4 a of the rotating shaft 4 are connected to the brackets 5 and 6. 4b is supported via bearings 11 and 12, respectively. Both the brackets 5 and 6 constitute a casing 13 that encloses the stator 2 and the rotor 3 together with the frame 1, and both end portions 4a and 4b of the rotating shaft 4 are connected to the casing 13 (both brackets 5 and 6). ) Protrudes outward.

Of both end portions 4a and 4b of the rotating shaft 4 protruding from the housing 13, one end portion 4a is an output shaft to which a rotating load (not shown) is connected. A fan 14 is attached to the other end 4 b of the rotating shaft 4. That is, the rotating electrical machine of the present embodiment is a fully enclosed outer fan-shaped rotating electrical machine.
The fan 14 has a mounting portion 14a at the center, and the mounting portion 14a is fitted to the other end portion 4b of the rotating shaft 4 so that the screw 15 is a liquid sealant in the radial direction (left and right in the figure). The fan 14 is attached to the other end portion 4b of the rotating shaft 4 by being screwed through and engaged with the rotating shaft 4. An umbrella-shaped circular base portion 14b exists radially outward from the mounting portion 14a of the fan 14, and a plurality of wing portions 14c project from the outer surface side of the base portion 14b.

Then, inward in the radial direction from the mounting portion 14 a of the fan 14, the end surface 4 c of the rotating shaft 4 faces the portion S where the mounting portion 14 a contacts the other end portion 4 b of the rotating shaft 4 from the contacting portion S. A non-porous covering portion 14d that covers water tightly is provided integrally.
In addition, a fan guard 16 that covers the entire fan 14 is coupled to the frame 1 at the end on the fan 14 side. The fan guard 16 has, for example, a honeycomb-like portion facing the fan 14 in the axial direction, and has a large number of ventilation holes.
Further, the frame 1 has a large number of fins 1a for heat dissipation, and all the fins 1a protrude in the radial direction of the frame 1 and extend in the axial direction.

In the case of the configuration as described above, when the coil 2 b of the stator 2 is energized, the rotor 3 rotates with the rotating shaft 4 and the fan 14 rotates integrally with the rotating shaft 4. The rotated fan 14 blows air toward the housing 13 and cools the housing 13 transferred from the stator 2.
The fan 14 has a cover portion 14d that faces the portion S where the mounting portion 14a and the other end portion 4b of the rotating shaft 4 are in contact and covers the end surface 4c of the rotating shaft 4 in a watertight manner from the contacting portion S. The portion 14d prevents water from entering from the outside through a portion where the mounting portion 14a of the fan 14 and the other end portion 4b which is the protruding portion of the rotating shaft 4 are in contact with each other.

Therefore, without the need for a conventional shade-like cover, it is possible to prevent deterioration of the lubricant applied between the rotating shaft 4 and the bearing 12 that supports the rotating shaft 4 due to water immersion. Furthermore, the occurrence of defects such as burnout can be avoided. In addition, since the conventional shade-shaped cover is not required, the ventilation performance by the fan 14 can be secured well, the cooling performance of the rotating electrical machine can be obtained well, and the product cost can be increased. Can be avoided.
Further, when, for example, a pump is coupled as a rotational load to the rotating electrical machine, it is possible to constrain the rotating shaft so that the rotating shaft does not rotate together, regardless of the conventional shade-shaped cover.

  3 and 4 show the second and third embodiments, the same parts as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted. Only the part is described.

[Second Embodiment]
In the second embodiment shown in FIG. 3, an engaged portion 21 for engaging a tool (not shown) is provided on the cover portion 14 d of the fan 14. In this case, the engaged portion 21 is a cross-shaped groove, and the rotation of the rotary shaft 4 from the fan 14 is restrained by inserting and engaging a tool having a cross-shaped tip at the engaged portion 21. Or a rotational force is transmitted from the fan 14 to the rotary shaft 4.

  By doing so, it is possible to more reliably prevent co-rotation of the rotating shaft 4 when, for example, a pump is coupled as a rotational load to the rotating electrical machine, or to transmit the rotational force to the rotating shaft 4 more reliably. it can.

[Third Embodiment]
Also in the third embodiment shown in FIG. 4, an engaged portion 31 for engaging a tool (not shown) is provided in the cover portion 14 d of the fan 14. In this case, the engaged portion 31 is a slot (−)-shaped groove, and a tool having a −-shaped tip is inserted into the engaged portion 31 and engaged with the engaged portion 31, whereby the rotating shaft 4 is rotated from the fan 14. , Or the rotational force is transmitted from the fan 14 to the rotary shaft 4.
By doing in this way, the effect similar to the above-mentioned can be acquired.

The rotating electrical machine described above is not limited to the above embodiment, and can be implemented with appropriate modifications within a range not departing from the gist.
In addition, although several embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the 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.

  In the drawings, 2 is a stator, 3 is a rotor, 4 is a rotating shaft, 4b is the other end (projecting portion) of the rotating shaft, 13 is a housing, 14 is a fan, 14a is a fan mounting portion, and 14d is a cover. , S is a portion where the mounting portion of the fan is in contact with the protruding portion of the rotating shaft, and 21 and 31 are engaged portions.

Claims (1)

In a rotating electrical machine having a stator and a rotor inside a housing, projecting a rotating shaft to the outside of the housing, and attaching a fan to the projecting portion of the rotating shaft by an attaching portion,
A cover portion is provided on the mounting portion of the fan so as to face the portion where the mounting portion and the protruding portion of the rotating shaft are in contact with each other, and covers the protruding end surface of the rotating shaft from the contacting portion.
An electrical rotating machine according to claim 1, wherein an engaged portion for engaging a tool that restrains rotation of the rotary shaft is provided in the cover portion.

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