JPH0697055B2 - Multiple seal type rolling bearing - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention is an improved seal configuration for a multiple seal type rolling bearing.

[Conventional technology]

Conventionally, a multi-seal type rolling bearing is assembled in a device used in a place where there is a lot of muddy water such as an agricultural machine. As a bearing of this type, for example, the structure disclosed in Japanese Utility Model Publication No. 46-3131 is used. Are known. In this bearing, the lips of the inner seal fitted on both ends of the outer ring in the axial direction are brought into contact with the concave grooves of the inner ring, and the outer ring of the inner seal is S
The structure is such that a flinger (outer seal) having a shaped cross section is fitted very closely to the inner ring, and a felt is interposed between the outer extended portion of this flinger and the inner seal to make contact.

[Problems to be solved by the invention]

Since the rolling bearing is provided with a predetermined clearance in the axial direction when assembled, the outer ring moves in the axial direction by the clearance with respect to the inner ring during operation. Therefore, in the above conventional rolling bearing, a large contact margin is provided in advance so that the contact pressure of the felt interposed between the inner seal and the outer seal does not drop below the required pressure even if the inner seal moves axially together with the outer ring. Need to be assembled.
For this reason, there is a drawback that the frictional resistance between the inner seal and the felt is increased, the rotational torque is increased, and the bearing performance is impaired.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a multiple seal type rolling bearing having a low torque seal structure by eliminating the above drawbacks.

[Means for solving problems]

The multiple seal type rolling bearing according to the present invention includes an inner seal having an outer ring attached to at least one shaft end side and an outer seal located axially outside of the outer ring and attached to the inner ring.

The inner seal is composed of a cored bar and an elastic member integrally provided on the axially inner side surface of the cored bar, and the cored bar has an outer peripheral portion and an intermediate portion extending axially outward from an inner peripheral edge of the outer peripheral portion, and an intermediate portion The inner peripheral portion of the elastic member extends radially inward, and the inner peripheral side of the elastic member has a lip portion extending obliquely inward on the outer side in the axial direction than the inner peripheral portion of the cored bar. It is located inside the axial direction.

The outer seal is composed of a cored bar and an elastic member integrally provided on an inner surface of the cored bar in the axial direction, and the elastic member is provided with a lip portion extending inward in the axial direction.

The inner seal has the outer peripheral portion of the core metal attached to the inner peripheral surface of the outer ring, and a non-contact type seal portion is formed with a slight gap between the inner peripheral portion of the core metal and the outer peripheral surface of the inner ring. The lip portion of the elastic member contacts the outer peripheral surface of the inner ring to form a contact-type seal portion.

The outer seal is attached by fitting the inner peripheral surface of the core metal to the outer peripheral surface of the inner ring, and the lip portion of the elastic member slides into contact with the outer peripheral surface of the middle portion of the core metal of the inner seal to make a contact-type seal. Make up part.

[Action]

In the multiple seal type rolling bearing of the present invention, the core metal of the inner seal is provided with the intermediate portion that extends outward in the axial direction, and the lip portion of the elastic member of the outer seal is slidably contacted with the outer peripheral surface of the intermediate portion. Even if the outer ring moves axially with respect to the inner ring when the bearing is used, the lip part of the elastic member of the outer seal contacts the outer peripheral surface of the middle part of the core metal of the inner seal and slides without changing contact pressure. Move.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a vertical sectional side view of an upper half portion showing a right side portion of a first embodiment of the present invention.

The bearing of this embodiment has a cage 15 between the outer ring 10 and the inner ring 14.
Is a deep groove ball bearing in which balls 16 with an arrow are arranged as rolling elements.

A peripheral groove 11 for mounting an inner seal is formed on the inner peripheral surface axially inward of the end surface of the outer ring 10, and the inner peripheral surface axially outer than the peripheral groove 11 is a large diameter portion 12. .

The inner seal 20 has a structure in which an elastic member 25 such as rubber is integrally fixed to the inner surface of the cored bar 21 in the axial direction by vulcanization adhesion or the like.

The core metal 21 of the inner seal 20 includes an annular outer peripheral portion 22 formed with an outer edge portion that bends inward in the axial direction, and an intermediate portion that extends from the inner peripheral edge of the outer peripheral portion 22 inwardly obliquely outward in the axial direction. Part 23
And an annular inner peripheral portion 24 extending radially inward from the inner peripheral edge of the intermediate portion 23.

The elastic member 25 of the inner seal 20 is attached to the inner surface in the axial direction from the outer peripheral portion 22 of the cored bar 21 to the intermediate peripheral portion 23 through the inner peripheral edge of the inner peripheral portion 24 to the radially outer portion, and is provided on the inner peripheral side. The attached annular portion 26 is provided with a lip portion 27 that extends inwardly obliquely inward in the axially outer direction with a space portion 28 between the annular portion 26 and the inner peripheral portion 24 of the cored bar 20.

The inner seal 20 has an outer peripheral portion 22 of the cored bar 21 and an elastic member 25.
It is assembled by press-fitting into the peripheral groove 11 of the outer ring 10 together with the outer peripheral part of the non-contact type seal with a small gap between the inner peripheral edge of the inner peripheral portion 24 of the cored bar 21 and the outer peripheral surface of the inner ring 14. The lip portion 27 of the elastic member 25 contacts the outer peripheral surface of the inner ring 14 to form a contact-type seal portion.

The outer seal 30 has a structure in which an elastic member 35 such as rubber is integrally fixed to the outer peripheral edge of the core metal 31 and the inner side surface in the axial direction by vulcanization adhesion or the like.

The core metal 31 of the outer seal 30 includes an annular inner peripheral portion 32 and an inner peripheral portion 32.
And an annular outer peripheral portion 34 that extends outward in the radial direction via a stepped portion 33 that is bent obliquely outward inward in the axial direction from the outer peripheral edge.

The elastic member 35 of the outer seal 30 includes an outer edge portion 36 that covers the axial inner side surface from the axial outer surface of the outer peripheral edge of the outer peripheral portion 34 of the core metal 31 through the outer diameter surface, and the outer peripheral portion 34 of the core metal 31. The annular portion 37 is attached to the inner surface in the axial direction between the stepped portion 33 and a part of the inner peripheral portion 32, and the annular portion 37 has a lip portion 38 extending obliquely outward on the inner side in the axial direction. Is located on the intermediate side.

The outer seal 30 is assembled by fitting the inner peripheral portion 32 of the core metal 31 to the outer peripheral surface of the inner ring 14, and the outer diameter surface of the outer edge portion 36 of the elastic member 35 is the large diameter portion 12 of the outer ring 10. A non-contact type seal portion is formed with a slight clearance from the inner peripheral surface of the end portion of the elastic member 35, and the lip portion 38 of the annular portion 37 of the elastic member 35 is attached to the inner seal 20.
A contact type seal portion is constituted by slidingly contacting the outer peripheral surface of the intermediate portion 23 of the core metal 21.

In the bearing having the above structure, the lubricating grease sealed inside the bearing is transferred to the outside by the contact-type seal portion formed between the lip portion 27 of the elastic member 25 of the inner seal 20 and the inner ring 14. Leakage is prevented.

Even when this bearing is used in the presence of a large amount of muddy water, the muddy water inside the bearing can be prevented by the non-contact type seal part formed between the outer edge portion 36 of the elastic member 35 of the outer seal 30 and the outer ring 10. Is prevented, and even if muddy water passes through this seal portion, the contact-type contact portion formed between the lip portion 38 of the elastic member 35 of the outer seal 30 and the intermediate portion 23 of the cored bar 21 of the inner seal 20. Intrusion is blocked by the seal part, and even if muddy water passes through this seal part, the inner peripheral part of the core metal 21 of the inner seal 20
The non-contact type seal part formed between the inner ring 14 and the inner ring 24 prevents the intrusion, and the muddy water which tries to enter the inside of the bearing through this seal part is the lip of the elastic member 25 of the inner seal 20. The contact-type seal portion formed between the portion 27 and the inner ring 14 will eventually block.

Even when the outer ring 10 moves axially with respect to the inner ring 14 during use of the bearing and the axial distance between the inner ring seal 20 and the outer seal 30 fluctuates, the lip of the elastic member 35 of the outer seal 30 is also changed. Since the portion 38 only repeats the vertical movement while sliding along the inclined surface of the intermediate portion 23 of the cored bar 21 of the inner seal 20, a situation in which the contact pressure is not significantly changed does not occur.

In particular, in this embodiment, the core metal 31 of the outer seal 30 is
Since the outer peripheral portion 34 of the outer peripheral portion 34 is provided with the outer edge portion 36 covering the elastic member 35, even if the clearance between the outer edge portion 36 of the elastic member 35 and the large diameter portion 12 of the outer ring 10 comes into contact with each other. It can be made extremely small so as not to interfere, and can be configured as a non-contact type seal portion having high sealing performance.

Further, since the core metal 31 of the outer seal 30 is provided with the stepped portion 33 by bending between the inner peripheral portion 32 and the outer peripheral portion 34, the strength of the core metal 31 of the outer seal 30 is increased. In addition to that, the contact area of the annular portion 37 of the elastic member 35 with respect to the cored bar 31 is increased, and the adhesive strength can be increased.

FIG. 2 is a vertical sectional side view of the upper half portion showing the right side portion of the second embodiment of the present invention.

The inner seal 20 and the outer seal 30 in this embodiment have the same constitutions as in the first embodiment,
The difference from the first embodiment is that the outer ring 10 has a short axial width, the outer edge portion 36 of the elastic member 35 of the outer seal 30 is axially outward from the end surface of the outer ring 10, and is located between the outer ring 10 and the outer ring 10. The non-contact type seal part is not configured.

With respect to the configuration other than the above, only the same reference numerals are given to the main parts, and detailed description will be omitted.

Also, the operation of this embodiment is the same except for the operation of the non-contact type seal portion of the outer seal, and therefore the repeated description is omitted.

FIG. 3 is a vertical sectional side view of an upper half portion showing a right side portion of a third embodiment of the present invention.

In this embodiment, the middle portion of the core bar 21 of the inner seal 20
23 has a cylindrical shape that extends outward in the axial direction in parallel with the axial direction, and the elastic member 25 is a part of the intermediate portion 23 of the cored bar 21 and the inner peripheral portion.
It is attached to a part of 24. The inner seal 20
The elastic member 25 may be attached to the inner surface in the axial direction from the outer peripheral portion 22 of the cored bar 21 through the intermediate portion 23 to the radially outer portion of the inner peripheral portion 24.

Further, the annular portion 37 of the elastic member 35 of the outer seal 30 is provided with a lip portion 38 extending inward in the axial direction in parallel with the axial direction, and the lip portion 38 is provided in the intermediate portion 23 of the core metal 21 of the inner seal 20.
The contact type seal portion is constituted by slidingly contacting the outer peripheral surface of the.

Since the configuration other than the above is the same as that of the first embodiment, the same reference numerals are given to the main parts, and the detailed description will be omitted.

According to this embodiment, when the outer ring 10 moves axially with respect to the inner ring 14 while the bearing is in use, the elastic member 35 of the outer seal 30 is
Since the lip portion 38 only slides in the axial direction along the cylindrical surface of the intermediate portion 23 of the cored bar 21 of the inner seal 20, no change in contact pressure occurs.

FIG. 4 is a vertical sectional side view of an upper half portion showing a right side portion of a fourth embodiment of the present invention.

In this embodiment, the core metal 31 of the outer seal 30 is not provided with a stepped portion and is molded into a flat annular shape as a whole, and the outer peripheral portion of the outer edge portion 36 of the elastic member 35 has an axially outer portion. Outer ring 10
It is located outside of the end face in the axial direction and is fitted and attached to the inner ring 14.

Since the configuration other than the above is the same as that of the first embodiment, the same reference numerals are given to the main parts, and the detailed description will be omitted.

According to this embodiment, when the bearing is used, the outer seal 30 and the outer ring are
The muddy water that tries to enter the inside of the bearing through the clearance between 10 and 10 is not shaken off by the centrifugal force of the outer edge portion 36 of the elastic member 35 of the outer seal 30 and shaken off to enter the inside of the bearing. The muddy water that tries to enter against this shaking-off action is blocked by the non-contact type seal part formed between the outer ring 10 and the axially inner portion of the outer peripheral surface of the outer edge portion 36 of the elastic member 35. To be done.

The multiple seal mechanism according to the present invention is not limited to the case where the multiple seal mechanism is provided at both left and right shaft ends of the bearing, and
Depending on the type of device, the mounting position of the bearing, etc., the multiple seal mechanism may be provided only on either shaft end side.

The present invention is not limited to the deep groove ball bearing of the above embodiment, and can be applied to other rolling bearings in the same manner as described above.

Further, the middle portion 23 of the core metal of the inner seal may extend obliquely outward in the axial direction, and the annular portion 37 of the elastic member of the outer seal has a lip portion 38 extending obliquely inward in the axial direction. It may be provided.

〔The invention's effect〕

As described above, the multiple seal type rolling bearing of the present invention extends axially outside between the outer peripheral portion and the inner peripheral portion of the core metal of the inner seal attached to the outer ring on at least one shaft end side of the bearing. An intermediate portion is provided to form a non-contact type seal portion between the inner peripheral portion of the core metal and the inner ring, and the lip portion of the elastic member integrally attached to the axial inner surface of the core metal and the inner ring An elastic member having a lip portion extending inward in the axial direction is integrally attached to the inner surface in the axial direction of the core metal of the outer seal attached to the inner ring, which constitutes a contact type seal portion, and the lip portion of the elastic member is attached. Is slidably contacted with the middle portion of the core metal of the inner seal to form a contact-type seal portion.

Therefore, according to the present invention, even when the outer ring moves axially with respect to the inner ring when the rolling bearing including the multiple seal mechanism including the inner seal and the outer seal is used, the lip portion of the elastic member of the outer seal can be used. The lip portion of the contact type seal part between the inner seal and the middle part of the core bar slides without changing the contact pressure to perform the desired sealing function. A rolling bearing provided with a low-torque multiple seal mechanism can be obtained without being affected by excessive contact pressure.

Further, according to the present invention, since the lip portion of the elastic member of the outer seal is in sliding contact with the intermediate portion axially inward of the inner peripheral portion of the core metal of the inner seal, the outer seal is brought close to the inner seal. It can be assembled, and the width dimension of the bearing can be shortened.

[Brief description of drawings]

FIG. 1 is a vertical sectional side view of an upper half portion showing a first embodiment of the present invention, FIG. 2 is a vertical sectional side view of an upper half portion showing a second embodiment of the present invention, and FIG. 3 is a third embodiment of the present invention. FIG. 4 is an upper half longitudinal side view showing an example, and FIG. 4 is an upper half longitudinal side view showing the fourth embodiment of the present invention. In the figure, 10 is an outer ring, 14 is an inner ring, 20 is an inner seal, 21 is an inner seal core metal, 22, 23, 24 are outer peripheral parts, middle parts, and inner peripheral parts of the core metal, and 25 is an inner seal elastic member. 27 is a lip portion of the elastic member, 30 is an outer seal, 31 is a core metal of the outer seal, 35 is an elastic member of the outer seal, and 38 is a lip portion of the elastic member.

Claims (3)

[Claims] 1. A rolling bearing which is sealed by an inner seal attached to at least one axial end of an outer ring and an outer ring seal located axially outside of the outer ring and attached to an inner ring. The seal is formed on the inner surface in the axial direction of the core metal having an outer peripheral portion attached to the outer ring, an intermediate portion extending axially outward from the inner peripheral edge of the outer peripheral portion, and an inner peripheral portion extending radially inward from the end edge of the intermediate portion. , An elastic member integrally provided with an inner peripheral portion having a lip portion that is located axially inward with respect to the inner peripheral portion of the core metal and extends obliquely inward on the axial outer side, and the outer seal is attached to the inner ring. An elastic member having a lip portion extending inward in the axial direction is integrally provided on the inner surface of the metal in the axial direction, and the inner peripheral portion of the core metal of the inner seal is separated from the outer peripheral surface of the inner ring by a slight gap. When the contact type seal part is configured At the same time, the lip portion of the elastic member is in contact with the outer peripheral surface of the inner ring to form a contact-type seal portion, and the lip portion of the elastic member of the outer seal is in sliding contact with the outer peripheral surface of the middle portion of the core metal of the inner seal. A multi-sealing type rolling bearing characterized by comprising a contact-type sealing portion. 2. A non-contact type seal in which an outer peripheral edge of an outer peripheral portion of a core metal of an outer seal is covered with an elastic member, and an outer diameter surface of the elastic member is slightly separated from an inner peripheral surface of an outer ring. The multi-sealing type rolling bearing according to claim 1, which constitutes a part. 3. The multiple seal type rolling bearing according to claim 1, wherein the outer seal has a cored bar whose outer peripheral portion is formed axially inward of the inner peripheral portion.