JPH01231633A - Rotary electric machine - Google Patents

Abstract

PURPOSE:To perform individual judgement of degradation of insulation of respective insulating members on the outer circumference of a shaft, by providing a conductive ring member held between the shaft and the frame cover in insulating state. CONSTITUTION:An insulating member 6l is provided at one end of a shaft 2 between the shaft 2 and a grounded frame 1, while insulating members 6r, 8 coupled in series are placed at the outer end of the shaft 2 then they are coupled in parallel. When insulation of the insulating members 6, 6r, 8 is not degraded, resistances at points M1, M2, M3 can be represented by the formulae I-III. When the insulating member 6r is degraded, i.e. when X2=0, R2=0, R1, R3not equal to 0 thus leaving resistance slightly. When the insulating member 6l is degraded, i.e. when X3=0, R3=0, R1, R2not equal to 0 thus leaving resistance lower than that when there is no problem in the insulation. By such arrangement, degradation of insulation can be detected without requiring overall dismantling.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a rotating electric machine equipped with an axial current prevention structure.

[Conventional technology]

FIG. 5 is a partially exploded side view of a conventional rotating electrical machine, in which numeral 1 indicates a metal cylindrical frame, and numeral 2 indicates a metal shaft of a rotor. The shaft 2 has metal bearings 3 at both ends.
4! , 3r, and each bearing 31, 3r is fixed to a metal placket 41.4r fixed to the center of each metal cover 5ff, 5r provided at both ends of the frame 1, respectively.

Cover 57! , both 6N of the peripheral part of 5r and frame 1
Flange part 1j provided inside the part! , Ir and a ring-shaped insulating material 6j between them! , 6r are interposed, and are held in an insulated state from each other, and are integrally fastened using bolts, nuts, etc.

Note that the frame 1 is grounded through an installation stand (not shown) or the like.

Therefore, since insulating materials 6ff and 6r are interposed between the bearing 31.3r of the shaft 2 and the frame I, both the bearings 3
Bearing 3p even if shaft voltage occurs between C3r.

As a result, each bearing 3L is cut off between 3r and frame 1.
No shaft current flows through 3r, and damage to bearing 3L3r is prevented.

Note that the bearings 31.3r on both sides are covered with insulating material 61.3r, respectively. ．． 6r is used to maintain the bearing 3123r insulated from the frame l in order to protect the bearing 3123r even when other equipment is directly connected to both ends of the shaft 2.

[ill the invention tries to solve! [Problem] By the way, in the conventional device as described above, a decrease in Meg is detected during maintenance inspection and the insulation material 6z is removed.

Even if it is assumed that the insulation properties of 6r have deteriorated, the insulation material 6j! , 6r needs to be replaced, and in the end, the entire structure including the frame 1, bracket 41.4r, etc., must be disassembled to make a decision, which is a hassle.

The present invention has been made in view of the above circumstances, and its purpose is to make it possible to determine whether or not the insulation properties of the insulating material have deteriorated without damaging the bearing insulation and without having to disassemble the entire bearing. Our goal is to provide rotating electrical machines.

[Means for Solving the Problems] In the rotating electric machine according to the present invention, an insulating material is provided between the frame and the cover on one end side of the frame to maintain the insulated state, and a frame is provided between the insulating material. , a conductive ring member held insulated from the cover is interposed.

[Effect]

According to the present invention, it is thereby possible to individually determine the presence or absence of insulation deterioration of each insulating material on the outer periphery of the bearing without disassembling the bearing.

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be specifically described below based on drawings showing embodiments thereof.

Fig. 1 is a partially fragmented side view of a rotating electric machine according to the present invention, Fig.
．． Figure 3 is a partially enlarged view showing the connection between the frame and the cover, in which 1 is the cylindrical frame, 2 is the shaft of the rotor, and 3j! , 3r is a bearing, i.

4r is a bracket, FM, 5r is a cover, and 6L6r is an insulating material, and all other members except the insulating material 6L6r are mainly made of metal.

The shaft 2 is a bracket l attached to the center of the cover 5C5r with both ends thereof being pivotally supported by bearings 3L3r! , 4r.

Cover 5j! , 5r are provided at the periphery of the cover 51 with an insulating material 61 interposed between the flanges ILb provided on the inside of both ends of the frame l in the axial direction. The insulating material 6r, the conductive ring member 7, and the insulating material 8 are interposed and are integrally fastened using bolts and bolts (not shown), respectively. The conductive ring member 7 is made of metal and has an annular shape, and a part of the periphery has a connecting piece (
(not shown), and the frame 1. is sandwiched between the insulating materials 6r and 8. It is interposed between the cover 5r and the cover 5r in an insulated state.

This allows each bearing 31°3r to pivotally support both ends of the shaft 2.
, the bracket 4r, and the cover 5r are maintained in an insulated state with respect to a frame grounded via an unillustrated installation stand or the like.

FIG. 4 shows each of the above-mentioned insulating materials 67! , 6r and 8, the shaft 2 and the grounded frame 1 are connected at one end of the shaft 2 with an insulating material 61 interposed, and at the other end of the shaft 2. Insulating material 6r connected in series
, 8 are connected in parallel.

In such a rotating electric machine according to the present invention, a decrease in Meg is detected during maintenance and inspection, and the insulating material 6j!
, 6r, the insulation properties of the conductive ring member 7 and the frame 1, between the conductive ring member 7 and one end of the shaft 2, and between the frame 1 and the shaft. 2
Regarding the three locations M, , Mg, and M, between the other end,
The resistance value is measured using a resistance measuring device such as a megger.

If the insulation properties of the insulating materials 61.6r and 8 have not deteriorated, and the respective resistance values are set to Xl+x2+X3 Ω, the respective resistance values of Ml, M2, and M3 are R+, Rz,
Rs is as shown in the following formulas (11 to (3)).

xl+x2+X3 By the way, if the insulation material 6r has deteriorated, in other words x
In the case of 2-0, (II ~ (31 2 to R2'=O.

R,, R3≠0, and although the value of R,, R, is smaller than the value when there is no problem with insulation, some resistance remains. Also, if the insulation IJ'6ffi has deteriorated, in other words, if x3-00, the same <
R:+=0. R+, R2≠0, and R,,R
Although the value of 2 is smaller than the value when there is no problem with insulation, it means that some resistance remains.

Of course, the presence or absence of insulation deterioration of the insulating material 8 can also be determined in the same manner.

Although the above-mentioned embodiment has been described with respect to a configuration applied to a horizontal rotating electric machine, the present invention is not limited to this at all, and it goes without saying that the present invention can also be applied to a vertical rotating electric machine. Furthermore, although the insulating material 8 has been described in terms of a configuration in which it is provided between the frame 1 and the cover 5r on the load side, it is substantially the same even if it is provided between the frame I and the cover 5p.

〔Effect of the invention〕

As described above, in the rotating electric machine according to the present invention, it is possible to detect the presence or absence of insulation deterioration without impairing the insulation function for the bearing, and without disassembling the whole, and to detect the presence or absence of insulation deterioration without disassembling the entire device. The present invention has excellent effects, such as the fact that it is sufficient to disassemble only the parts, which greatly reduces the labor required for maintenance and inspection work.

[Brief explanation of the drawing]

Fig. 1 is a partially fragmented side view of a rotating electric machine according to the present invention, Fig.
, 3 is a partially exploded side view showing the connecting portion between the frame and the cover, FIG. 4 is an electric circuit diagram including each insulating material, and FIG. 5 is a partially exploded side view of a conventional rotating electric machine. ■...Frame 2...Shaft 3L3r...Bearing 4
1.4r...Bracket FM, 5r...Cover 6
L6r... Insulating material 7... Conductive ring member 8...
・Insulating material In the figures, the same symbols indicate the same or equivalent parts. Agent Masu Oiwa 5th

Claims (1)

[Scope of Claims] 1. A rotating electric machine in which bearings for supporting both ends of a rotor shaft are fixed to covers fixed to both ends of a frame with insulating materials interposed therebetween, the frame and its A rotating electrical machine characterized by interposing an insulating material between the cover at one end portion and the insulating material to maintain the insulating state between the two, and a conductive ring member between the insulating material and the conductive ring member that is insulated from the frame and the cover. .