JP2017034795A - Rotary electric machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rotary electric machine capable of maintaining bearing grease on an electric motor at appropriate level and ensuring the efficiency of the electric motor while preventing abnormal degradation or leakage of grease.SOLUTION: The rotary electric machine comprises: a grease injection path 1a formed between a bearing 4 and an end bracket 1; a grease discharge port 1b communicated with the grease injection path 1a; an annular body having an outer periphery plane which is configured to be rotatably in contact with an inner peripheral surface opposite to an outer periphery of a shaft 5 being interposed by a grease pocket 6, and to be rotatably in contact with an inner peripheral surface of a shaft through hole of the end bracket 1; and a grease scraper extending in a lubricant flow path, which is disposed at the bearing side of the annular body.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a device for discharging a lubricant supplied to a bearing and its peripheral bearings, and a rotating electrical machine having the device.

  In general, the discharge of lubricant (grease, etc.) supplied to a bearing of a rotating electric machine such as an electric motor often depends on a natural drop due to gravity or a force pushed out by a newly lubricated lubricant. On the other hand, if the lubricant is not properly discharged or excessively lubricated, the lubricant pocket for storing the waste lubricant will fill up and the rolling resistance of the bearing will increase, leading to abnormal heat generation. There was a risk of shortening the service life. Therefore, it is important to discharge the lubricant appropriately.

  JP-A-2002-66295 (Patent Document 1) is known as a related art in this technical field. In Patent Document 1, for the purpose of providing a vertical stirrer in which injected grease is sequentially discharged and the bearing temperature does not rise abnormally, a bearing 20 and a bearing holder 24 and the injected grease are placed in the bearing. In the vertical stirrer in which the baffle ring 26 for retaining and the seal mechanism 40 are sequentially fitted to the drive shaft and the grease discharge hole 27 penetrating the bearing holder 24 in the lateral direction is provided below the baffle ring. A structure in which the sleeve 41 of the seal mechanism at the same level as the grease discharge hole 27 has the grease discharge blade 28 is disclosed.

JP 2002-66295 A

  As mentioned above, many of the lubricant discharging methods of rotating electrical machines are the natural fall method or the method of injecting and extruding new lubricant, but the lubricant is solidified due to aging and does not fall naturally, or depending on the supply amount The lubricant pocket may become full, and the lubricant may leak from locations other than the discharge port, such as the shaft penetration part of the end bracket. Leakage of lubricant from locations other than the lubricating oil outlet will contaminate the environment and should be avoided.

  Patent Document 1 discloses a mechanism for forcibly discharging the lubricant, and a structure in which the grease discharge blade constantly pushes the grease that has flowed downward from the bearing to the grease discharge hole side during rotation as the drive shaft rotates. It has become. Therefore, the problem that the grease discharge stress of the grease discharge blade becomes a rotation loss of the drive shaft remains. In particular, Patent Document 1 has a problem that the supply amount of grease is increased for the purpose of preventing abnormal temperature rise of the bearing in a closed space where heat dissipation is difficult, which further increases the rotation loss.

In order to solve the above-described problems, the present invention is, as an example, a rotating electrical machine, a lubricant channel formed between a bearing and a bracket, and a discharge hole communicating with the lubricant channel. An annular body having an inner peripheral surface facing the outer periphery of the drive shaft through a gap and an outer peripheral surface rotatably contacting the inner peripheral surface of the drive shaft through hole of the bracket, and an annular body extending into the lubricant flow path And a lubricant discharge member disposed on the bearing side.

  According to the present invention, overfilling of the lubricant inside the bearing box can be prevented without making a complicated structure, and leakage from other than the grease discharge port, abnormal temperature rise of the bearing, and loss increase can be prevented. .

It is sectional drawing of the grease discharge structure of the electric motor in a present Example. FIG. 2 is a partially enlarged view of FIG. It is a cross-sectional perspective view of the grease discharge structure of the electric motor in a present Example. It is the schematic diagram which showed the structural example of the lubricant discharging apparatus in a present Example. It is sectional drawing of the grease discharge structure of the conventional electric motor.

  First, a conventional method for discharging a lubricant (such as grease), which is a premise of the present invention, will be described. FIG. 5 is a cross-sectional view of a conventional grease discharging structure for an electric motor. In FIG. 5, the arrows indicate the flow of lubricated grease. The grease lubricated from the grease nipple 3 passes through the grease injection path 1 a provided in the end bracket 1, and covers the bearing inner cover 2, the bearing 4, and the end bracket. The waste grease is supplied to the inside of the bearing box 1 and accumulated in the grease pocket 6 and discharged from a grease discharge port (discharge hole) 1b provided in the lower portion of the end bracket 1. The shaft 5 is rotatably supported by the end bracket 1 via a bearing 4. In such a system that relies on the force of gravity falling due to gravity or the force pushed out by newly lubricated grease, the grease may not be discharged normally, increasing the rolling resistance of the bearing and increasing the bearing and lubricant. There was a problem that the lifetime was shortened.

  Therefore, in this embodiment, a mechanism for forcibly discharging the lubricant with a simple structure is provided. Hereinafter, the present embodiment will be described with reference to the drawings.

  FIG. 1 shows a cross-sectional view of a grease discharging structure for an electric motor in the present embodiment. 1, the same components as those in FIG. 5 are denoted by the same reference numerals, and description thereof is omitted. 1 is different from FIG. 5 in that a lubricant discharging device 7 is provided. As shown in FIG. 1, the lubricant discharge device 7 is a device for scraping out grease in a grease pocket 6 which is a lubricant flow path formed between the bearing 4 and the end bracket 1.

  FIG. 2 is an enlarged view of a peripheral portion of the lubricant discharging device 7 surrounded by a dotted line in FIG. As shown in FIG. 2, the lubricant discharge device 7 includes a grease scraper 7b and an annular body 7a that are lubricant discharge members. FIG. 3 shows a cross-sectional perspective view of the grease discharge structure of the electric motor in this embodiment. In FIG. 3, the end bracket 1 is a cross-sectional view, and a perspective view of the shaft 5 and the annular body 7 a of the lubricant discharging device 7 is shown. As shown in FIGS. 2 and 3, the annular body 7 a of the lubricant discharging device 7 rotates with the inner peripheral surface facing the outer periphery of the shaft 5 through a gap and the inner peripheral surface of the shaft 5 through hole of the end bracket 1. It is an annular body having an outer peripheral surface that comes into contact with it, and rotates independently of the rotation of the shaft 5. Further, the grease scraper 7b is fixed and arranged on the annular body 7a. Therefore, by rotating the annular body 7a as necessary, the grease in the grease pocket 6 can be scraped out to the grease discharge port 1b by the grease scraper 7b and forcibly discharged.

  The lubricant discharging device 7 can be fixed to the end bracket 1 by fitting with an inlay, and can be freely attached to and detached from the end bracket 1 by moving in the direction of the shaft 5. In other words, the annular body 7a has a multistage shape in which the outer cylindrical surface has an outer diameter in the axial direction smaller than the inner diameter in the axial direction.

  FIG. 4 is a schematic diagram illustrating a configuration example of the lubricant discharging device 7. FIG. 4A shows the lubricant discharging device 7 shown in FIGS. 1 to 3, in which a cylindrical portion on the bearing side is provided on the annular body 7a, and a grease scraper 7b is fixed thereto. . In FIG. 4B, there is no cylindrical portion on the bearing side of the annular body 7a, and the grease scraper 7b is integrally extended from the intermediate cylindrical portion. Further, as shown in FIG. 4C, the grease scraper 7b is bolted to an intermediate cylindrical portion with the structure of FIG. 4B. Further, as shown in FIG. 4D, although the rotation direction is limited, in order to efficiently scrape, the grease scraper 7b may be angled with respect to a direction perpendicular to the drive shaft. That is, the grease scraper 7b is inclined with respect to the rotation direction of the annular body 7a. Like illustration, you may incline toward the rotation direction of the annular body 7a, and you may incline toward the reverse rotation direction as shown with a dotted line. In other words, the angle may be given toward the inner diameter side of the annular body 7a, or the angle may be given toward the outer diameter side. If it is assumed that the grease scraper 7 is rotated in both directions, it is desirable to install the grease scraper 7b so as to be perpendicular to the rotating direction.

  In the above description, the grease scraper 7b is described as one, but a plurality of grease scrapers 7b may be provided.

  Further, there is a possibility that the grease in the grease pocket 6 is solidified and the grease to be discharged continues to rotate together with the lubricant discharging device 7 even if the lubricant discharging device 7 is rotated, and the grease cannot be scraped to the grease discharging port 1b. Conceivable. As shown in FIG. 3, it is also effective to provide a discharge wall 1c for pushing out the grease scraped by the grease scraper 7b in the vicinity of the grease discharge port 1b. A protrusion may be used instead of the discharge wall.

  Further, when not in use, the lubricant discharge device 7 is preferably fixed so as not to be detached from the end bracket 1 especially during operation of the electric motor. Therefore, a fixing bolt may be provided in the lubricant discharging device 7 and fixed to the end bracket 1 with a bolt. If the bolt cannot be directly fixed to the end bracket 1 due to the structure, the lubricant discharge device 7 is sandwiched and fixed to the end bracket 1 using a discharge device fixing plate 8 and a discharge device fixing bolt 9 as shown in FIG. May be. That is, the engaging member (discharge device fixing plate 8) that is in contact with the outer end surface of the annular body 7a and the outer end surface of the bracket 1 on the outer diameter side of the shaft 5 is engaged with the outer end surface of the annular body 7a. There is a bolt (discharge device fixing bolt 9) for fixing the stop member. In this case, the discharge device fixing plate 8 may have a disk shape surrounding the shaft 5 or a member that covers only a part of the outer periphery of the shaft 5.

  In addition, a handle may be attached to the grease discharge device 7 in order to rotate the lubricant discharge device 7, but the grease discharge device fixing bolt 9 can also be used as a handle, thereby making the structure easier. Can be expected.

  Further, a groove may be provided in the inner diameter portion of the lubricant discharging device 7 so that grease does not leak out.

  As described above, the present embodiment is a rotating electrical machine, and includes a lubricant channel formed between a bearing and a bracket, a discharge hole communicating with the lubricant channel, an outer periphery of a drive shaft, and a gap. And an annular body having an outer peripheral surface rotatably contacting the inner peripheral surface of the bracket and the inner peripheral surface of the drive shaft through hole of the bracket, and a lubricant extending in the lubricant flow path and disposed on the bearing side of the annular body It is set as the structure which has a discharge member.

  Accordingly, overfilling of the lubricant inside the bearing box can be prevented without a complicated structure, and leakage from other than the grease discharge port, abnormal temperature rise of the bearing, and increase in loss can be prevented. In addition, the lubricant can be discharged regardless of whether the lubricant channel is up, down, left, or right.

  Although the embodiments have been described above, the present invention is not limited to the above-described embodiments, and includes various modifications. For example, the above-described embodiments have been described in detail for easy understanding of the present invention, and are not necessarily limited to those having all the configurations described.

DESCRIPTION OF SYMBOLS 1 ... End bracket, 1a ... Grease injection path, 1b ... Grease discharge port, 1c ... Discharge wall, 2 ... Bearing cover, 3 ... Grease nipple, 4 ... Bearing, 5 ... Shaft, 6 ... Grease pocket, 7 ... Lubricant Discharge device, 7a ... annular body, 7b ... grease scraping, 8 ... grease discharge device fixing plate, 9 ... grease discharge device fixing bolt

Claims (9)

A lubricant channel formed between the bearing and the bracket;
A discharge hole communicating with the lubricant flow path;
An annular body having an inner peripheral surface facing the outer periphery of the drive shaft via a gap and an outer peripheral surface that rotatably contacts the inner peripheral surface of the through hole of the drive shaft of the bracket;
A rotating electrical machine comprising: a lubricant discharge member extending into the lubricant flow path and disposed on the bearing side of the annular body. The rotating electrical machine according to claim 1,
The rotating electrical machine, wherein the annular body can be fixed to the bracket. The rotating electrical machine according to claim 2,
A rotating electrical machine, wherein the annular body and the bracket are fixed using a spigot fitting. The rotating electrical machine according to claim 2,
A rotating electrical machine using a bolt for fixing the annular body and the bracket. The rotating electrical machine according to claim 4,
A rotating electrical machine characterized in that the annular body and the lubricant discharge member disposed on the annular body are rotated using a bolt used for fixing the annular body and the bracket as a handle. The rotating electrical machine according to claim 1,
A rotating electrical machine having a wall or a protrusion installed so as to guide the lubricant scraped by the lubricant discharge member to the discharge hole. The rotating electrical machine according to claim 1,
The rotating electrical machine according to claim 1, wherein the lubricant discharging member is disposed on the annular body at an angle with respect to a direction perpendicular to the drive shaft. The rotating electrical machine according to claim 1,
A rotating electrical machine comprising a plurality of the lubricant discharge members. The rotating electrical machine according to claim 1,
A rotating electrical machine comprising a groove in an inner diameter portion of the annular body.

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