JPS622906Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a water draining device for a rotating electrical machine such as an electric motor or a generator.

[Conventional technology]

Generally, in a rotating electrical machine such as an electric motor or a generator, a water drain hole is provided at the bottom of the housing to prevent water from accumulating inside the machine due to dew condensation or the like.

However, for example, in starter motors installed in vehicles such as cars and motorcycles, the lower part of the housing may also be exposed to water, so water can infiltrate into the housing through the drain hole, causing electrical insulation to deteriorate. There were problems such as corrosion of conductive parts and poor lubrication of moving parts.

Therefore, conventionally, in this type of rotating electric machine, a water drain device is used, which is formed by connecting a pipe such as a rubber tube to a water drain hole provided in the lower part of the housing.

In addition, Japanese Utility Model Application Publication No. 49-115605 discloses that a cylindrical drain breather jacket with a drainage hole at the bottom has a burr on the peripheral edge during punching, and a drain hole located at a position off the center. A drain breather has been proposed in which a plurality of partition plates each having holes are stacked one upon another with the burrs facing the same direction.

[Problem that the invention attempts to solve]

However, a water draining device using a rubber tube has the disadvantage that the water ingress prevention effect is not sufficient because the inlet position of the water ingress is simply shifted by the pipe.

Furthermore, the drain breather described in Japanese Utility Model Application Publication No. 49-115605 has the drawback that it requires a large number of man-hours for processing and assembling, resulting in low productivity.

SUMMARY OF THE INVENTION An object of the present invention is to provide a water draining device for a rotating electrical machine that can eliminate the drawbacks of the prior art, improve productivity, and completely prevent water intrusion.

[Means for solving problems]

The water draining device for a rotating electric machine according to the present invention includes:
A labyrinth tube is connected to a drain hole provided in the lower part of the housing of the rotating electrical machine, and the labyrinth tube includes a pair of pieces that are placed face-to-face to form a tube shape, and both pieces are aligned with each other. They are integrally molded and connected to each other by bendable hinge parts formed between adjacent sides of the , and the engaging parts formed on each of the other sides engage with each other. Therefore, it is configured to maintain the tube shape, and furthermore, a plurality of baffle plates are arranged on the inner circumferential surfaces of both pieces alternately with respect to the center line direction in a state where the tube body is formed. At the same time, each piece protrudes from the other piece, leaving a passage on the other piece.

[Effect]

According to the above-mentioned means, the water in the housing is
The water is discharged to the outside through the drain hole → the passage formed between each baffle plate in the labyrinth pipe. On the other hand, water does not enter the housing because it is blocked by the baffle plate of the labyrinth pipe.

And since the labyrinth tube is integrally molded,
It is suitable for mass production, and the assembly into the rotating electrical machine requires only connecting the labyrinth pipe to the drain hole of the housing, resulting in extremely high productivity.

〔Example〕

FIG. 1 is a partially cutaway side view showing an embodiment of a water draining device for a rotating electrical machine according to the present invention, and shows a case where the water draining device is applied to a starter motor, which is an example of a rotating electrical machine.

In this embodiment, a drain hole 3 is opened laterally (horizontally) in the lower part of the housing 2 containing the motor 1, etc., and a labyrinth pipe 4 made of synthetic resin or the like is provided in the drain hole 3. are connected so that the passages communicate with each other. This tube 4 is formed into an elbow tube shape, and the opposite end side to the connection side hangs down vertically.

This labyrinth tube 4 is constructed as shown in FIGS. 2 to 6. This tube 4 is a pair of pieces 5
a, 5b, and both pieces 5a, 5b each have a shape formed by vertically halving an elbow tube body. A baffle plate 6 having a substantially semicircular plate shape is provided on the inner peripheral surface of the vertical portion of both pieces 5a and 5b.
2 pieces and 1 piece, respectively, are provided protrudingly so as to partition a semi-cylindrical space, and 1 piece of one piece 5a
One baffle plate 6 is placed in the center of the other piece 5b.
The baffle plates 6, 6 are arranged at upper and lower positions, respectively. As shown in FIG. 5, both pieces 5a and 5b are placed with their open surfaces facing upward and adjacent to each other on one side of their vertical portions via bendable hinge portions 7 formed on the adjacent sides. are connected to each other, therefore both pieces 5
a and 5b are integrally molded from synthetic resin or the like at the same time. Engagement parts 8 and 9 that engage with each other are protruded from both ends and the center of both pieces 5a and 5b, respectively, and both pieces 8 and 9 have a semi-cylindrical shape. The engaging state is brought about by holding the engaging portion 9 formed in the.

Next, the action will be explained.

The water in the housing 2 gradually flows down and collects in the lower water drain hole 3, from which it flows into the labyrinth pipe 4 and is discharged. This drainage water passes through the pipe 4 and reaches the baffle plate 6, where it is obstructed, but since it is constantly subject to gravity, it eventually passes through the baffle plate 6 and flows down from the lower end opening of the pipe 4 to the outside.

When the pipe 4 is exposed to water from below, the water enters the pipe 4 from the lower end opening. However, this infiltration force comes into contact with the baffle plate 6 and the infiltration force is weakened, and eventually the infiltration force is lost. The water that has lost its infiltration force is now subject to gravity, so as with the drainage from inside the housing,
It goes down the baffle plate 6 that it has just crossed and flows down from the opening at the lower end of the tube. Therefore, water is completely prevented from flowing back into the housing from the drain hole.

In the above embodiment, the case where the labyrinth pipe 4 is formed as a curved pipe has been described, but as shown in FIG. 6, it may be formed as a straight pipe 4A.

Further, the baffle plate of the labyrinth tube is not limited to the above-mentioned embodiment, but may be configured as shown in FIGS. 8A, B, C, and D, respectively.

FIG. 8A shows an embodiment in which the tips of the baffle plates of both pieces overlap with the other, and according to this embodiment, the effect of preventing water from entering becomes even more remarkable.

FIG. 8B shows an embodiment in which the upper surface of the baffle plate is formed into an inclined surface. According to this embodiment, the drainage action can be promoted by the inclined surface without impairing the effect of blocking water intrusion. In addition, it is possible to improve the ease of demolding during piece molding.

FIG. 8C shows an embodiment in which the upper baffle plate is formed short and the lower baffle plate is lengthened to overlap. According to this embodiment, water intrusion from the outside is prevented. At the same time, it becomes easier to drain water from inside.

Figure 8D shows an embodiment in which the baffle plates are overlapped and their tips are tilted downward (toward the discharge port). According to this embodiment, the effect of preventing external water intrusion and the effect of promoting internal drainage are achieved. It becomes even more noticeable.

Note that the structure of the baffle plates is not limited to this embodiment, and the number of baffle plates may be increased or decreased as desired. Furthermore, the labyrinth tube is not limited to a cylindrical shape.

[Effect of idea]

As explained above, according to the present invention, since labyrinth pipes in which an appropriate number of baffle plates are alternately arranged leaving passages on the inner peripheral surface of the other side are used as drain pipes, water can be drained from inside the housing. Infiltration from the outside can be completely prevented without impairing the function.

In addition, since the labyrinth tube is configured to have a split structure and the baffle plate is configured to protrude from the other piece leaving a passage, the labyrinth tube can be molded with a mold and can be manufactured at low cost. In addition, the shape of the baffle plate can be freely designed because it has good die-cutting properties.

Furthermore, in the drain breather described in Japanese Utility Model Application Publication No. 49-115605, it is necessary to store multiple partition plates one by one with their burrs facing the same direction within the outer cover. In the present invention, since the work of connecting the labyrinth pipe to the drain hole is sufficient, the assembly workability is good, and together with the integral moldability of the labyrinth pipe, productivity can be greatly improved.

[Brief explanation of the drawing]

Fig. 1 is a partially cutaway side view showing one embodiment of the present invention, Fig. 2 is an enlarged partial sectional view of the main part, Fig. 3 is an enlarged cross-sectional view taken along the line of Fig. 2, and Fig. 4 is an enlarged cross-sectional view of the main part. Second
Fig. 5 is an exploded perspective view of the labyrinth tube, Fig. 6 is an assembled perspective view, Fig. 7 is a perspective view of main parts showing another embodiment of the present invention, Fig. 8A, B, C, and D are partial sectional views showing modified examples of baffle plates, respectively. DESCRIPTION OF SYMBOLS 1... Motor, 2... Housing, 3... Drain hole, 4... Labyrinth pipe, 5a, 5b... Piece, 6... Baffle plate, 7... Hinge part, 8, 9...
Engagement part.

Claims (1)

[Scope of utility model registration request] A labyrinth pipe is connected to a drain hole provided in the lower part of the housing of the rotating electrical machine, and the labyrinth pipe includes a pair of pieces that are placed face-to-face to form a pipe shape, and both pieces are connected to each other. They are integrally molded and connected to each other by bendable hinge parts formed between adjacent sides, and the engaging parts formed on each of the other sides engage with each other. Further, a plurality of baffle plates are arranged on the inner circumferential surfaces of both pieces alternately with respect to the center line direction in a state where the tube body is formed. A water draining device for a rotating electric machine, which is protruded from each piece, leaving a passage in the other piece.