JPH10339329A - Sealing device for rolling bearing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a high dust preventing performance and a characteristic of a low torque, and suppress noise of a lip by setting a ratio between a lip base thickness and a distance between a lip gravity center and a core end part to a specified level and less. SOLUTION: A sealing device 1 is formed as a seal of a contact type comprising a rubber seal 1a and core 1b annually, the thickness T of a lip 3 is thinned, the cross section of the lip 3 is enlarged so as to form the device 1 as a seal design. A fitting part 2 is fitted to the fitting groove 6 of an outer wheels 5, and the lip 3 is brought into contact with an inner wheel 7 side. The seal device 1 is formed in such a constitution that a ratio L/T between the thickness T of the lip 3 and a distance L between the gravity center 4 of the lip 3 and the core end part 1b is set to 1 or more and 2 and less. When the ratio L/T is 2 and less, the other constitution is set optionally without limiting to a shape and it is changed to the other shape within a range. When the ratio L/T is 2 or more, vibration is increased, a noise generating ratio is increased. When the ratio L/T is 2 and less, vibration is reduced, and the noise is not generated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sealing device for a rolling bearing used in an electromagnetic clutch or the like, and more particularly to an improvement in a contact type sealing device.

[0002]

2. Description of the Related Art Bearings used in automobile engines, such as electromagnetic clutches, are required to have both high dust-proof and low-torque characteristics, and in order to have both of these characteristics, a thin lip base is required. , Resulting in a sealing device design with a large lip cross-sectional area.

[0003]

However, there is no sealing device of such a configuration having both of the above characteristics which can suppress the noise caused by the squealing sound (vibration sound) of the sealing lip.

The inventor of the present invention has completed the present invention by paying attention to the fact that the lip squealing noise generation rate is caused by bearing rotation.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the prior art, and has as its object to provide both a high dust-proof property and a low torque property.
An object of the present invention is to provide a contact-type rolling bearing sealing device capable of suppressing a lip noise (vibration noise).

[0006]

The technical solution of the present invention for solving the above-mentioned problems is a contact-type seal comprising a rubber seal and a metal core, wherein the lip is brought into contact with the race. In the apparatus, the ratio between the lip base thickness and the length from the center of gravity of the lip to the end of the metal core is set to 2 or less.

[0007]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a rolling bearing sealing device according to an embodiment of the present invention.

The drawings show an embodiment of the sealing device for a rolling bearing of the present invention used for a rolling ball bearing (balls are not shown). In this embodiment, reference numeral 1 denotes a sealing device, and FIG.
Denotes an outer ring and 7 denotes an inner ring (see FIG. 1).

Further, the outer ring 5 and the inner ring 7 are not limited to the illustrated example, and are not limited to rolling elements (balls, rollers, etc.) and retainers (not shown). Other structures can be appropriately changed within the scope of the present invention, and the description thereof is omitted in this specification.

In the present embodiment, the sealing device 1 is a contact-type seal composed of a rubber seal 1a and a core bar 1b in an annular shape. The seal device 1 has a high dust-proof property and a low torque. The seal design has a small thickness T and a large cross-sectional area of the lip 3. The fitting portion 2 is fitted in the fitting groove 6 of the outer ring 5 so that the lip 3 is brought into contact with the inner ring 7 side.

The sealing device 1 has a lip ternary thickness T.
And the length L from the center of gravity 4 of the lip 3 to the end 1b 'of the cored bar.
Is set to 2 or less. Note that in reality, 1 ≦ L
/ T ≦ 2.

The sealing device 1 has a ratio of L / T of 2
Other configurations are not limited to the shapes shown in the drawings and are optional as long as they have the following configurations.
Other shapes are possible within the scope of the invention.

[0013] Figure 2, the sealing lip and the original thickness T of 3, the sealing lip from the center of gravity 4 3 and the ratio of the length L to the end 1b of the core 1b ', the vibration velocity of the lip portion (× 10 ^{- 3} m / s), the vertical axis represents the vibration speed of the lip, and the horizontal axis represents L.
/ T ratio. Also, FIG. 3 shows the relationship between the original thickness T of the seal lip 3 and the center of gravity 4 of the seal lip 3 to the end 1 of the metal core 1b.
The relationship between the ratio of the length L to b 'and the squealing sound generation rate (%) is shown, the ordinate represents the squealing sound generation rate (%), and the abscissa represents the L / T ratio. 2 and 3, when the L / T ratio is larger than 2, the vibration is large and the squealing sound generation rate is high, but when the L / T ratio is 2 or less, the vibration is small and the squealing sound generation rate (%) is 0 ( It does not occur).

[0014]

According to the present invention, the above structure is provided.
Since the ratio between the lip base thickness and the length from the center of gravity of the lip to the end of the metal core is made to be as small as 2 or less, the vibration is small, and as a result, the squealing sound (vibration sound) of the seal does not occur.

Therefore, it is possible to provide a contact-type rolling bearing sealing device which has both high dustproofness and low torque and can suppress the squeal (vibration) of the lip.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional front view showing an embodiment of the present invention.

FIG. 2 is a diagram showing the relationship between the ratio of the original thickness T of the seal lip to the length L from the center of gravity of the seal lip to the end of the core metal, and the vibration speed of the lip.

FIG. 3 is a diagram showing the relationship between the ratio of the original thickness T of the seal lip, the length L from the center of gravity of the seal lip to the end of the core metal, and the squealing sound generation rate.

[Explanation of symbols]

 1: Sealing device 1b ': Core end portion 3: Lip 4: Lip center of gravity 5: Outer ring 7: Inner ring L: Length from seal lip center of gravity to core end T: Seal lip base thickness

Claims (1)

[Claims] 1. A contact type sealing device comprising a rubber seal and a core bar, wherein a lip is brought into contact with a raceway, wherein a ratio between a lip base thickness and a length from a lip center of gravity to an end of the core bar is determined. A sealing device for a rolling bearing, wherein the number is 2 or less.