JPS58623A - Oil-containing sintered bearing - Google Patents

Abstract

PURPOSE:To provide a bearing itself with an oil supply function, by chamfering the inner edge of at least one end face of the bearing and providing grooves extending from the chamfered edge to the peripheral surface of the bearing. CONSTITUTION:The inner edge of at least one of the end faces 9a, 9b of an oil- containing sintered bearing 9 is chamfered at 10. Grooves 11 are provided so that they extend from the chamfered edge 10 to the peripheral surface of the bearing 9. The grooves 11 function to conduct outgoing oil to the peripheral surface of the bearing 9.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a sintered oil-impregnated bearing that is particularly suitable for relatively small-diameter motors, including coreless motors.

This type of oil-impregnated bearing manufactured by powder metallurgy includes:
It has the excellent advantage of being self-lubricating. This self-lubricating property is due to the fact that the oil impregnated in the bearing emerges from the gap between the shaft and the bearing as the shaft rotates. , resulting in a decrease in lubrication ability. Therefore, in order to prevent this decrease in lubrication ability, a lubrication mechanism such as KFi or a felt material wrapped around the outer periphery is generally attached when a sintered oil-impregnated bearing is used.

However, in the case of wrinkled motors, there are extremely difficult problems in installing such a lubrication mechanism, both in terms of the available space and in terms of not impairing the wrinkled appearance. Therefore, in the case of small motors, no lubrication mechanism is attached as in other motors.

By explaining this point in some detail using the coreless motor shown in FIG. 1 as an example, the purpose of Jin's invention will be made clear. It is located inside the casing l and supports the oil-impregnated bearings 2 and 3 #i motor shaft 4 in question here, and these bearings 2 and 3 themselves are fixed to a resin support 5 by press fitting, etc., and this resin The support 5 is attached to the inner surface of the casing l by means of an iron core 6. on the other hand,
The l1fi element 7 and the coil 8 are press-fitted onto the motor shaft 4, so that the round shaft 4 is supported by the bearing 2゜3 and rotates at the same time as the l1fi element 7 and the coil 8. become.

When the motor shaft 4 rotates in this way, the bearings 2 and 3
The oil impregnated therein seeps out into the contact area between the bearings 2 and 3 and the motor shaft 4. As a result, the above-mentioned lubrication occurs, but some of the oil that has seeped out is scattered to the outside from the opening of the bearing hole. This rounding causes oil stains inside the casing, and the oil that is impregnated with the casing is consumed rapidly, causing the lubrication ability to deteriorate in a short period of time.

This caused problems such as self-seizing of the O4-tashaft 4, resulting in problems in durability.

This item 4@ was created taking the above points into consideration. Therefore, it is possible to provide a sintered oil-impregnated bearing in which the inside of the bearing has the same function as the conventional oil bunkering mechanism described above, without requiring any new space. I love you.

Hereinafter, 1FK of the present invention will be explained in detail with reference to the attached FIGS. 2 and 3.

In the sintered oil-impregnated bearing 9 of the present invention, as shown in FIG.
A key feature is that a chamfer LO is provided at the intersection with LOIIS, and a groove 11 is provided running from the chamfer LOIIS to the outer circumferential side of the bearing.

Regarding the chamfer o10, either taper or radius is fine, but if the chamfer is tapered, the dimension should be 0.
．． The angle of the round chamfer 10 is preferably about 2 degrees or more, and is usually 45 degrees, but it can also be made smaller. The point is that the oil that flows out at the time of turning is the chamfer 1.
All you have to do is make it possible to smoothly connect to 擲11 弒 along 0w6 minutes.

On the other hand, the groove 11ri following the chamfer 10, as shown in FIG. 3, guides the outflowing oil toward the outer circumferential side of the bearing 9 as indicated by the arrow indicated by the broken line. Therefore, the shape of the groove 11 may be arbitrary as long as the guiding function is not impaired, but from the viewpoint of workability, it is preferable to form it in a straight line. Straight groove 1
1, the actual depth Fio is 1 W or more, and the width is πDx (0.05 to 0.7), where D is the inner diameter of the bearing 9.
It is better to

Furthermore, the number of grooves 11 can be one or more (preferably 2 to 6), but in the case of multiple grooves, it is of course better to arrange them at equal angles along the circumferential direction. be.

In the case of the illustrated example, the handle lO and the groove 11 are connected to the bearing 9.
However, when used in place of the bearing 2.3 in the coreless motor mentioned above, it is necessary to install a It is not necessary to provide the recesses 10 and grooves 11, but when the sides of the nine ends are open, it is also more effective for oil recovery to use a washer 12 as shown in Figure 3.

As described above, in the sintered oil-impregnated bearing 9 according to the present invention, by providing the face relief lO and the groove 11 on at least four end faces 9R (9b) portions of the bearing, the oil bunkering mechanism can be attached thereto. Because of this function, it is possible to obtain the excellent effect of being able to easily solve problems such as oil stains and sealed envelopes when there is no oil bunkering mechanism. It was a platform. Since these chamfers 10 and grooves 11 do not require any new space, they can immediately respond to the trend toward smaller diameters in coreless motors and the like.

Although the present invention is particularly suitable for relatively small vibration motors such as coreless motors, it can also be widely applied to other types of motors.

By briefly describing the results of a mounting test using a coreless motor, the effects of this invention will be specifically clarified.

■ [Ear J bearing] Material: 8n91G, 00.5-1 remaining is substantially Ou, density is a, 9g/cc, oil content is 2
1-(Volume) 0 dimensions: outer diameter 8 g, inner diameter 3.2 da, thickness 4
．． 7+w.

■ [Test results] 1) In the case of the conventional example without groove 11 but with a 0.15° chamfer on the inner diameter surface: Seizure occurred after 1500 hours of operation, and there was constant oil stains inside the casing. . Furthermore, at the end of this operation, the oil content had decreased at 9 trenches.

11) In the case of the present invention which is similar to the example shown in FIG.
): No seizure was observed even after 2500 hours of operation, and there was no oil stain inside the casing. Also, at the end of the operation,
The oil content was 13-, and it was flexible for use.

44. Brief description of the drawings 8g1 Figure is a sectional view showing the configuration of a coreless motor using this type of bearing, Figure 2 shows an embodiment of the present invention, (a) is a front view, and (a) is a front view. 1), and FIG. 3 is a partial view showing the use case lIl of the example in FIG. 2.

9... Bearing according to this invention, 9m, 9b... End face,
9C... Bearing inner diameter surface, 10... Chamfering, 11...
groove.

Applicant Mitsubishi Metals Corporation Representative Bensioshi Shiga Masatake

Claims (1)

[Claims] At least one end face portion of both end faces of the bearing,
A sintered oil-impregnated bearing characterized in that a chamfer is formed at the intersection of the end and the inner diameter surface of the bearing, and a groove is provided extending from the chamfer to the outer circumferential side of the bearing.