JPS6030849B2 - bearing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a bearing device used in a high-speed rotating machine such as a gas turbine reducer.

Generally, for high-speed, high-load rotating shafts, so-called combination bearings, in which two bearings are placed side by side in the direction of the sea bream, are used to reduce the load on each bearing, thereby preventing a decline in the durability of the bearings. There is.

In a bearing device using such a combination bearing, conventionally, as shown in FIG. 3, two angular ball bearings 61,
An annular spacer 63 is inserted between the bearings 62, a lubricating oil injection nozzle 64 is provided in the spacer 63, and the bearings 61 and 62 are lubricated with the lubricating oil A from the nozzle 64.

In this case, in order to apply the necessary preload to each angular contact ball bearing 61, 62, the bearing housing is configured with a hydraulic cylinder 65, and the high pressure oil B supplied to the pressure chamber 66 of this hydraulic cylinder 65 causes the hydraulic Move the cylinder 65 to the right 6
7, thereby pressing the outer rings 69, 70 in the right direction 67 through the nut 68 screwed onto the hydraulic cylinder 65. The above is an example of a bearing device that uses a hydraulic cylinder 65 to generate pressing force, but since it is necessary to operate the hydraulic cylinder 65 before the bearings 61 and 62 rotate, it is necessary to use a separate hydraulic cylinder. The disadvantage is that a generator is required.

An object of the present invention is to provide a bearing device which has an excellent effect that does not require generation of hydraulic pressure before operation as described above by incorporating a pressing method using a spring.

In order to achieve the above object, the present invention sets a pair of bearings to bear thrust loads in different axial directions, and uses a spring that presses the outer end surface of the outer ring of one of the bearings in the axial direction. The outer end surface of the outer ring of the other bearing is brought into contact with the stopper portion formed in the bearing housing, and the spacer inserted between both outer rings and having a lubricating oil injection nozzle is inserted between both inner rings. A lubricating oil injecting nozzle is inserted between the pair of bearings by the spring member so that it can float in the opposite direction between the two outer rings while the spacer inserted between them is pressed between the inner rings. This eliminates the need for a hydraulic pressure generating device. Embodiments of the present invention will be described below with reference to the drawings.

In FIG. 1, reference numeral 11 denotes a rotating shaft, such as an input shaft in a gaster pin speed reducer, which rotates at high speed.
13 are installed respectively. two bearing devices 12,
13 are basically the same, so here we will use the left bearing device 1.
2 will be explained.

Unlike the conventional example shown in FIG. 3, the pair of angular contact ball bearings 14 and 15 are arranged face-to-face, so that each bearing bears a thrust load in different axial directions. As clearly shown in FIG. The outer end surface (right end surface) of the inner ring 17 in the bearing 15
is in direct contact with the stopper step portion 21 of the rotating shaft 11.

Therefore, the above-mentioned subesa 18 is
It is squeezed between. Outer rings 22, 2 of the bearings 14, 15
3 is housed in a bearing housing 24, and this bearing housing 24 is housed in a reduction gear case 25. A rotation prevention ring 26 is inserted between the bearing housing 24 and the reduction gear case 25, and its projection 26a prevents the housing 24 from rotating relative to the case 25. Between the inner end surfaces of both outer rings 22 and 23,
An annular spacer 27 is inserted, and a lubricating oil injection nozzle 28 is provided on this spacer 27, and the lubricating oil A supplied to the injection nozzle 28 through the lubricating oil supply passage 29 is transferred to the injection nozzle 28. is injected into each bearing 14,15.

In FIG. 1, reference numeral 31 denotes a spring portion that presses the outer rings 22 and 23 in the direction of the ball, and is enclosed in the bearing housing 24.
One end 31a is held under pressure by a holding member 32 screwed into the bearing housing 34, and the other end 31b holds the outer end surface (left end surface) of the outer ring 22 of the bearing 14 in the right direction 33.
Press to.

With the outer ring 22 being pressed in the right direction 33 and the aforementioned spacer 18 being pinched between the two inner rings 16 and 17, the spacer 27 is moved as shown in FIG. is set to be able to float in the direction of the ball between both outer rings 22 and 23,
As a result, the outer ring 23 of the bearing 15 is subjected to a pressing force in the left direction 35 by the stopper portion 34 of the bearing housing 24 . Therefore, the pressing force of the spring member 31 is canceled out within the bearing housing 24 and is not transmitted to the rotating shaft 11.
In this way, the pressing force (preload force) is not transmitted to the rotating shaft 11, which is completely different from the subordinate example shown in FIG. Furthermore, the spacer 27 is set to be able to float in the axial direction, which is in stark contrast to the conventional spacer 68 shown in FIG. 3, which is pinched between the outer rings 69 and 70. be. The spacer 27 is in loose contact with the inner peripheral surface of the bearing housing 24 in order to be able to float in the axial direction. Therefore, a gap 36 is created between both side surfaces of the spacer 27 and both outer rings 22 and 23. Not only does it occur;
A slight gap 37 is also created between the outer peripheral surface of the spacer 27 and the inner peripheral surface of the bearing housing 24.

Therefore, it seems that there is a possibility that a part of the lubricating oil A supplied from the lubricating oil supply passage 29 to the injection nozzle 28 may leak into the bearings 14 and 15 through the gaps 36 and 37, but in reality In the type of bearing having a retainer 39 of a pawl 38, the lubricating oil A that has entered the gap 36 between the spacer 27 and the outer rings 22, 23 due to the centrifugal force accompanying the rotation of the retainer 39 is It has been confirmed that this forms a high-pressure liquid film and that this high pressure suppresses the leakage. However, when the centrifugal force of the retainer 39 exceeds 4 mm, such as during deceleration operation, the leakage suppressing effect may not be expected to be very effective. Therefore, a seal ring 41 made of rubber is fixed to both sides of the outer peripheral portion of the spacer 27 by, for example, welding, and this seal ring 41 prevents the leakage. The above seal ring 41
is made of highly elastic rubber, so the spacer 27 is
It is not strongly compressed between 2 and 23 and is still able to float in all directions of the axis. Further, the outer rings 22 and 23 of each of the bearings 14 and 15 are not fixed to the bearing housing 24 but are internally inserted into the bearing housing 24 so as to receive sufficient pressing force from the spring member 31.

Therefore, in order to prevent the outer rings 22 and 23 from rotating with respect to the bearing housing 24, a first rotation preventing pin 42 is inserted through the stopper portion 34 of the bearing housing 24 to prevent the outer rings 22 and 23 from rotating.
3, and a second detent pin 43 is inserted into the outer rings 22 and 23 through the spacer 27.
The second anti-rotation pin 43 also prevents the spacer 27 from rotating relative to the bearing housing 24. In the above configuration, the left angular ball bearing 14 of the bearing device 12 in FIG. The necessary preload is created and it operates normally.

At this time, the load surfaces 44, 4 on the left bearing 14
The load line 46 connecting 5 points is located on the right side on the rotating shaft 11 and has a load point 47, whereas the load line 46 connecting the load surfaces 48 and 49 on the right bearing 15 is located on the left side. and has a load point 51, so both load points 47 and 51
The distance a in the axial direction becomes smaller, and the rotation axis 11
The tolerance for load imbalance between the bearings 14 and 15 due to the inclination of the bearings becomes wider. Therefore, the allowable degree of inclination of the rotating shaft 11 can be increased. Although the front-to-face bearing configuration that can reduce the above-mentioned distance a has been widely used in the past, this invention has the advantage of being applied to a front-to-face bearing configuration with a spacer. . Moreover, since the pressing force in the axial direction of each bearing 14, 15 is an elastic force by the spring part village 31, the inner ring 16,
When the ball 17 becomes hot and expands greatly in the axial direction, the outer rings 22 and 23 are displaced in the axial direction against the elastic pressing force.
, 23 is prevented from becoming excessive. If the above-mentioned pressing force is not an elastic force but a fixed force, the contact pressure of the balls 38 becomes excessive due to expansion of the inner rings 16 and 17, which may cause the bearings 14 and 15 to break. Furthermore, since both the angular contact ball bearings 14 and 15 are assembled face-to-face, unlike the conventional case, the entrance areas of the openings 52 and 53 facing each other with the injection nozzle 28 in between are equal. , 15 becomes the same, and as a result, each bearing 14
, 15, and the durability of the bearing device is improved.

Further, as described above, the spacer 27 is connected to the bearing housing 24.
The spacer 27 can be easily attached to the bearing housing 24 because the spacer 27 can be loosely attached to the inner circumferential surface of the bearing housing 24 .

Although angular contact ball bearings 14 and 15 were used in the above embodiment, deep groove ball bearings may also be used. In that case, the outer ring of each bearing receives an elastic force in a certain direction, thereby preventing the balls from floating. Since this is suppressed, fretting between the balls and the inner and outer rings is prevented, which has the effect of improving the durability of the bearing.

Further, as in the case of angular contact ball bearings, there is an advantage that the distance in the direction of the load between the load points of each deep groove ball bearing is reduced, and the permissible inclination of the rotating shaft is correspondingly increased. As explained above, according to the present invention, in a bearing device in which a lubricating oil injection nozzle is disposed between a pair of bearings, each bearing is preloaded with a simple and inexpensive structure to prevent normal operation of the bearings. It is possible to provide guarantees, prevent damage due to thermal expansion, and prevent fretting.

Furthermore, since the axial distance between the load points of each bearing is reduced and the permissible inclination of the rotating shaft is increased, attachment of the bearing device to the rotating shaft is facilitated. Furthermore, since the spacer provided with the injection nozzle may be loosely attached to the bearing housing, the spacer can be easily attached to the bearing housing.

In addition, when high-speed angular contact ball bearings are used as bearings, since they are used in a face-to-face combination, each angular contact ball bearing is equally lubricated, which has the advantage of improving the durability of the bearing.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view showing an embodiment of the present invention, FIG. 2 is a longitudinal sectional view showing the main part of FIG. 1, and FIG. 3 is a longitudinal sectional view showing a conventional example. 11... Rotating shaft, 12, 13... Bearing device, 14,
15... A pair of bearings, 16, 17... Inner ring, 18.
...Surface, 22, 23... Outer ring, 24... Bearing housing, 27... Spacer, 28... Lubricating oil injection nozzle, 34... Stopper part, A...; Lube oil. Figure 1 Figure 3 Figure 2

Claims (1)

[Claims] 1 A pair of bearings that are arranged in parallel in the axial direction and bear thrust loads in different axial directions are fitted into a bearing housing, and a spacer is interposed between the inner rings of these bearings, and a spacer is interposed between the outer rings. A lubricating oil injection nozzle for the bearing is provided in this spacer, a spring member is provided to press the outer end surface of the outer ring in one bearing in the axial direction, and a stopper portion formed in the bearing housing is provided with a lubricating oil injection nozzle for the bearing. A bearing device, wherein the outer end surface of the outer ring is abutted against the spacer, and the spacer is configured to float in the axial direction between the outer rings with the spacer being pressed between the inner rings.