JPH0138332Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a skidding prevention device when a rolling bearing such as a ball bearing or a roller bearing is used under light load and high speed rotation.

In general, in rolling bearings, driving force from the inner or outer ring is transmitted to the rolling elements by the shear friction force of an oil film that does not occur on the rolling contact surface. Therefore,
Lubrication of rolling bearings is essential to prevent wear, heat generation, seizure, etc.

However, in the case of radial type rolling bearings used under high speed and light loads, there is a limit to the driving force that can be exerted through the oil film formed between the outer ring or the inner ring. Due to the increased rolling resistance due to centrifugal force, the viscosity of the oil, and the stirring resistance, the rolling elements are no longer able to perform pure rolling interlock and rotate while sliding. Abnormal damage caused by this orbital slip phenomenon is called Schizdeng.
The above-mentioned sliding phenomenon occurs in both ball bearings and roller bearings under high-speed, light-load operating conditions.

As a means to prevent such squeezing, the radial clearance of the bearing is partially reduced by making the outer ring raceway of the bearing elliptical or eccentric (Japanese Patent Application Laid-open No. 52-36245, 91652
(No. 1), or one in which the housing bore fitted with the outer ring of the bearing is partially relieved, and the deformation of the outer ring is used to partially reduce the radial clearance of the bearing (Japanese Patent Publication No. 25-966). However, in the conventional products mentioned above, each of these is determined by a preset amount of eccentricity or escape amount, and this can be arbitrarily changed (adjusted) during use.
The drawback was that I couldn't do it. That is,
The drawback was that each method had to be treated individually depending on the conditions of use.

In addition to the above-mentioned conventional methods, for example,
Publication No. 6055 discloses skidding prevention using hydraulic pressure, but since the type disclosed in this publication relates to an auxiliary bearing installed in parallel to the main bearing, a mating member is attached to the outer circumferential surface of the outer ring of the bearing. There is no fitting surface for the outer ring (housing), and a minute gap is formed over the entire width and circumference of the outer ring, and the structure is such that fluid passes through this minute gap, so there is no problem with fluid flow. However, this type requires a special sealing structure to prevent fluid leakage, and there are still problems with this type, such as the fact that it cannot be used as a normal main bearing because it does not have the above-mentioned fitting surface. .

This invention eliminates the above-mentioned drawbacks and problems by adopting the configuration described in claim 1 of the utility model registration claim, and also partially reduces the amount of preload in the radial direction of the bearing during use. The gap in the radial direction of the bearing is adjusted arbitrarily to make the gap in the radial direction negative, thereby effectively preventing the above-mentioned skidding.

Next, an embodiment of the device of this invention shown in FIGS. 1 to 3 will be explained. 1 is a shaft, 2 is a cylindrical roller bearing, 3 is an inner ring thereof, 4 is a cylindrical roller, 5 is an outer ring, and 6 is an outer ring. 4 is fitted into a ring body which can be handled integrally with the outer ring 5; 7 is a housing; 71 is a pressure fluid passage formed in the housing and is connected to an external pressure oil supply source (not shown); Connected.

The bearing 2 is a well-known NU-type cylindrical roller bearing with an outer ring collar, and the ring body 6 integrally fitted and held with the outer ring 5 of the bearing 2 has a ring body 6 as shown in FIGS. 1 and 2. At approximately the center of the inner circumferential surface corresponding to the outer circumferential surface of the outer ring, a fitting surface 51 is left on both sides thereof to tightly fit with the outer ring and form a sealing part at the fitting part, and the fitting surface 51 is formed in the circumferential direction. a circumferential groove 61 connected to the
The recessed portion 62 connected to the circumferential groove 61 is approximately symmetrical.
The circumferential groove 61 is connected to a supply hole 63 provided through the annular body in the radial direction. As shown in FIG. 3, the ring body 6 is integrated with the bearing 2 by press-fitting the outer ring of the bearing 2 onto its inner peripheral surface. In this case, it is necessary that the mutually fitting surfaces 51 are fitted in a sealed state so that the pressure oil supplied to the recess through the circumferential groove 61 does not leak. Therefore, if the sealing performance is poor with mere fitting, an appropriate sealing means such as an O-ring or adhesive may be used on the fitting surface.

In the above embodiment, the circumferential groove 61 has a width l ₁ that does not impede the passage of pressure oil, and the width l ₂ of the recess satisfies the relationship l ₁ < l 2 and the width _{l 2} of the annular body is is within a width l ₃ and is deeper than the circumferential groove 61;
Further, the circumferential length _l4 is determined in consideration of the amount of deformation applied to the outer ring.

Next, the action (relationship with pressure oil) during operation in the above embodiment will be explained in the assembled state shown first. Circumferential groove 61
is fed under pressure and supplied to the recess 62. That is,
Pressure oil supplied from the outside passes through a passage 61A surrounded by the circumferential groove 61 and the outer circumferential surface of the outer ring, and is supplied to a space 62A surrounded by the recess and the outer circumferential surface of the outer ring. Then, the outer ring 5 of the bearing is deformed into an elliptical shape pressed by the pressure of the pressure oil in the space 62A, the radial clearance of the deformed portion becomes a negative value, and a preload in the radial direction is applied to that portion. As a result, the driving force between the rolling elements and the raceway increases.

Since the skiddening prevention device of this invention is constructed as described above, the outer ring is deformed by the pressure of the pressure fluid supplied from the outside, and as a result, the radial clearance of the bearing partially becomes a negative value. Preload is applied in the radial direction. As a result, it goes without saying that it is possible to prevent Schizdeng.
In particular, since the preload in the radial direction can be easily adjusted by changing the pressure of the fluid, the skidding can be more effectively prevented, and assembly and handling become easier.

As for the pressure fluid supplied from the outside, there are cases in which lubricating oil supplied to the bearing is used, and pressure fluid (oil, air, etc.) which is supplied independently (dedicated) and unrelated to bearing lubrication. There are cases.

Furthermore, in the embodiment, a configuration was described in which the bearing was fitted and held in the bore of the housing via the annular body, but the outer ring of the bearing was directly fitted and held in the bore without using the ring. It may also be implemented. In this case, the aforementioned circumferential groove 61 and recess 62 formed on the inner peripheral surface of the annular body are formed on the inner peripheral surface of the housing that faces the outer ring.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view of a main part showing an embodiment of the device of this invention, Fig. 2 is an axial cross-sectional view of the ring body used in the device shown in Fig. 1, and Fig. 3 is a sectional view of the ring body used in the device shown in Fig. 2. FIG. 2 is a cross-sectional view of a main part showing a state in which the shown ring body and the cylindrical roller bearing are fitted together. In the symbols of the examples, 1 is the shaft, 2 is the cylindrical roller bearing,
3 is an inner ring, 4 is a cylindrical roller, 5 is an outer ring, 6 is an annular body,
61 is a circumferential groove, 62 is a recess, 63 is a supply hole, and 7 is a housing.

Claims (1)

[Claims for Utility Model Registration] (1) A holding device for a rolling bearing in which the outer ring 5 of the rolling bearing is fitted and held in the bore of a housing 7 either directly or through an annular body 6 fitted to the outer ring 5. At approximately the center of the inner circumferential surface of the housing 7 or the ring body 6, which corresponds to the outer circumferential surface of the outer ring 5, a fitting surface 51 that closely fits the outer ring is left on both sides, and an external pressure fluid is provided. It has a circumferential groove 61 connected to the supply source, and one or more recesses 62 that are wider and deeper than the circumferential groove 61 and connected to the circumferential groove 61, and the pressurized fluid passes through the circumferential groove 61 from the pressure fluid supply source. A skidding prevention device for a rolling bearing, characterized in that an outer ring portion facing the recess 62 is pressed by the pressure fluid supplied to the recess 62, and a preload is applied to the portion in the radial direction. (2) Utility Model Registration Claim 1: The skidding prevention device for a rolling bearing according to claim 1, wherein the pressure fluid is part of lubricating oil that is branched from a lubricating oil path that lubricates the bearing.