JPH038060Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a waterproof structure for a motor that is installed in a location exposed to muddy water, rainwater, etc.

[Problems to be solved by the prior art and the invention]

Generally, some motors of this type are sometimes assembled in locations where they are exposed to mud or rainwater, and such motors must be appropriately waterproofed. However, conventionally, the waterproof structure of the motor is as shown in FIG. 3, in which a bearing step 2a is formed at the bottom of the cylinder of the yoke 2, and a bearing 7a provided with an appropriate waterproofing means is installed inside the bearing step 2a. However, the waterproof structure provided on the bearing part 7a is still not sufficient, especially when it is heavily exposed to water, or when a motor for a fan installed in a car, motorcycle, etc. In such cases, there is a drawback that when the motor is exposed to water, it is impossible to prevent water from penetrating through the output shaft. For this reason, it is proposed to add some kind of waterproofing means to the yoke, but in this case, the structure for assembling the waterproofing means to the yoke becomes complicated, and new methods such as the need to prepare a specially shaped yoke are required. There were some shortcomings that became a problem.

[Means to solve the problem]

The present invention was devised in view of the above-mentioned circumstances with the aim of providing a waterproof structure for a motor that can eliminate these drawbacks.
A bearing stepped portion is formed in the yoke of the motor in which a bearing portion for the output shaft is housed, and a cap body is integrally fitted onto the outer periphery of the bearing stepped portion to cover the protruding portion of the output shaft from the yoke. In addition, the cap body is further characterized in that an oil seal whose lip portion slides in contact with the output shaft is installed inside the cap body, and grease is filled between the oil seal and the yoke.

With this configuration, the present invention makes it possible to utilize the yoke with a bearing step, which has been widely used in the past, as it is, and to create a motor with an advanced waterproof structure. .

〔Example〕

Next, one embodiment of the present invention will be described based on the drawings. In the drawings, reference numeral 1 denotes a motor for a fan, and the motor 1 is composed of a yoke 2, a permanent magnet 3, a rotor 4, an output shaft 5, etc., which are all conventional. A fan 6 and a cup washer 11, which will be described later, are integrally supported by a tightening nut 8 at the protruding end of a protruding portion of the output shaft 5 that protrudes from the yoke 2.

A bearing stepped portion 2a is bent at the bottom of the cylinder on the fan mounting portion side of the yoke 2, and a bearing portion 7 is formed on the inner peripheral side of the bearing stepped portion 2a, so that the output shaft 5 can rotate. It is supported on a shaft for free movement. on the other hand,
Reference numeral 9 denotes a cap body, and the cap body 9 is formed of a cylindrical body with a stepped structure, with a stepped portion 9c formed between a large diameter portion 9a and a small diameter portion 9b. The stepped portion 9c of the body 9 includes a flange portion 10 having a larger diameter than the large diameter portion 9a, and a flange portion 10 having a larger diameter than the small diameter portion 9b.
It has a structure in which it is fitted onto the outer periphery of the body and is integrally fitted and fixed by appropriate fixing means such as spot welding. And the cap body 9 is
By press-fitting the large diameter portion 9a to the outer periphery of the bearing stepped portion 2a of the yoke 2, it is integrally assembled to the yoke 2, but in this state,
The small diameter portion 9b of the cap body 9 is configured to loosely fit over a protruding portion of the output shaft 5 that protrudes from the yoke 2. In addition, an oil seal 12 whose lip portion 12a is configured to come into sliding contact with the output shaft 5 is housed in the small diameter portion 9b of the cap body 9. is filled with grease G,
The sliding surface between the lip portion 12a and the output shaft 5 is lubricated. Further, when the cap body 9 is assembled to the yoke 2, the outer periphery of the flange 10 is connected to a cup washer 11 that rotates integrally with the fan 6.
They face each other so that a narrow gap A exists between them and the inner circumferential surface of the cup washer 11. edge and yoke 2
The waterproof structure of the embodiment of the present invention is constructed in this way.

In the embodiment of the present invention constructed as described above, the fan 6 is rotated by the rotation of the output shaft 5 driven by the motor 1, and a wind blowing effect is produced as in the conventional case. Even if the motor is exposed to rainwater or the like, water can be reliably prevented from entering the motor. In other words, rainwater is 1
The infiltrated water then tries to further infiltrate into the motor 1 along the output shaft 5, but this water enters the oil seal 12 installed in the cap body 9,
The lip portion 12a of the oil seal 12 is subjected to a double and almost complete waterproofing effect due to the grease G filled therein to lubricate the lip portion 12a, and therefore water is completely prevented from penetrating into the motor 1. do not have.

In this way, in the present invention, the oil seal 12
The double waterproof structure of the oil seal lubrication grease G can reliably prevent water from entering the motor 1.
It is possible to impart highly waterproof performance to the motor. Moreover, this high degree of waterproof performance is achieved by fitting the cap body 9 into the cap body 9 by effectively utilizing the outer circumference of the bearing stepped portion 2a required for providing the bearing portion 7 for the output shaft 5. The oil seal 12 and the grease G can be applied reliably by an extremely simple structure in which the oil seal 12 and the grease G are filled internally. can be carried out as is, and there is no need to prepare a specially shaped yoke 2 to provide excellent waterproofing means. Furthermore, the lip portion 12a is lubricated by being supplied with grease G little by little due to the sealing effect of the oil seal 12, so no unnecessary load is applied to the rotation of the output shaft 5.

Further, as shown in this embodiment, gaps A and B are formed between the yoke 2 side and the cup washer 11, and these gaps A and B are formed as the motor is driven.
Since the two-stage labyrinth effect at B can be achieved,
It is possible to more reliably prevent muddy water etc. from entering into the cup washer 11, and it is also possible to expect the effect of sucking out the grease G to the lip portion 12a, thereby further improving the waterproofing effect. This is advantageous in that it also achieves a reliable and effective protection function for the lip portion 12a.

[Function and effect]

In summary, since the present invention is constructed as described above, water that attempts to enter the motor is absorbed by the oil seal filled inside the cap body provided on the yoke to cover the protruding portion of the output shaft. The grease provides a double waterproofing effect, and therefore, infiltration into the motor is almost completely prevented. Moreover, this high degree of waterproofing can be achieved using an extremely simple structure in which the cap body is fitted onto the outer periphery of the bearing stepped portion of the yoke, with the interior filled with an oil seal and grease. To,
Since this cap body can be mounted by effectively utilizing the bearing step part of the yoke, there is no need to use a specially shaped yoke, and it can be attached directly to a motor using a yoke with a general-purpose structure in which a bearing step part is formed. This is something that can be implemented.

[Brief explanation of the drawing]

The drawings show an embodiment of the waterproof structure of the motor according to the present invention, in which FIG. 1 is a sectional front view of the main part of the motor, FIG. 2 is an enlarged sectional view of the main part, and FIG.
The figure is a sectional front view of a main part of a motor showing a conventional example. In the figure, 1 is a motor, 2 is a yoke, 2a is a bearing stepped portion, 5 is an output shaft, 7 is a bearing portion, 9 is a cap body, 12 is an oil seal, and G is grease.

Claims (1)

[Scope of utility model registration request] A bearing stepped portion is formed in the yoke of the motor in which a bearing portion for the output shaft is housed, and a cap body is integrally fitted onto the outer periphery of the bearing stepped portion to cover the protruding portion of the output shaft from the yoke. The waterproof structure for a motor is further characterized in that the cap body includes an oil seal whose lip portion slides in contact with the output shaft, and grease is filled between the oil seal and the yoke.