JPS6334320A - Sealing device for rolling bearing - Google Patents

Abstract

PURPOSE:To prevent the entry of mud into a bearing, by providing sealing portions at three positions of an inner periphery, an outer periphery and an intermediate therebetween of the bearing, and thereby hindering the mud from entering from any directions. CONSTITUTION:When mud in a puddle passes through a sealing portion formed by a middle portion 54 of an outer seal 50, the mud is collected in a space 61 defined by an intermediate lip 47 of an inner seal 40. Further, there is formed a non-contact sealing portion between a lip portion 49 of the intermediate lip 47 and the middle portion 54 of the outer seal 50, so that the entry of the mud to the inner side may be prevented. Further, there is formed an inner peripheral sealing portion between a main lip portion 44 and an inner ring 20, so that the mud having entered a space 62 may be prevented from entering the inside of the bearing. Thus, the entry of the mud from any directions may be prevented.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a sealing device for a rolling bearing, and in particular improves the sealing structure and ease of assembly of a rolling bearing sealed by a multi-layered seal. be.

[Conventional technology]

BACKGROUND ART Conventionally, as a rolling bearing for machines and devices used in places where there is a lot of muddy water and other foreign matter, a structure shown in FIG. 5, for example, is known.

In the figure, balls 30 are disposed as rolling elements between an outer ring (stationary raceway ring) 10 fitted to the housing l and an inner ring (rotation side raceway ring) 20 fitted to the shaft 2. A deep groove ball bearing is shown. A double sealing mechanism consisting of an external seal 4 and a slinger 8 is provided on the axially outer side of this bearing.

A lip portion 6 consisting of an inner lip portion 6a and an outer lip portion 6b is provided on the inner peripheral side of the outer seal 4, and a lip portion 6 is provided on the radially inner side of the inner lip portion 6a and the radially outer side of the outer lip portion 6b. 7a and 7b are provided respectively.

The above-mentioned external seal 4 is fitted and attached to the inner circumferential surface of the housing 1 on both the left and right sides, and the slinger 8 has a U-shaped cross section, and the opening side of the fixing part 8b on both the left and right sides is axially inward. The slinger 8 on the left side is fitted onto the outer peripheral surface of the shoulder of the shaft 2, and the slinger 8 on the right side is fitted onto the outer peripheral surface of the inner ring holder 2a fitted onto the shaft 2.

The lip 7a of the inner lip portion 6a of the left outer seal 4 is attached to the outer peripheral surface of the shoulder of the shaft 2, and the lip 7a of the inner lip portion 6a of the right outer seal 4 is attached to the outer circumferential surface of the inner ring retainer 2a. oriented and in contact, both outer seals 4
The lips 7b of the outer lip portion 6b contact the planar annular portion of the slinger 8 in the direction opposite to the ball 30 and facing radially outward, so that a contact type seal portion is formed at two locations. It is configured. In addition to this, the inner lip portion 6a
Grease is sealed in the space 8d between the outer lip 6b and the outer lip 6b to prevent muddy water and other foreign matter from entering the bearing through the outer lip 6b. Grease is also sealed between the pair of external seals 4.

[Problem that the invention seeks to solve]

In a rolling bearing provided with the sealing mechanism as described above, muddy water and the like outside the bearing accumulates on the outer periphery of the outer lip portion 6b, but enters the outer lip portion 6b by passing through the glue knob 7b. This muddy water etc. that entered is removed from the inner lip portion 6a.
and the outer lip portion 6b.
However, the muddy water etc. that come out from this space 8d are
Invades the inside of the bearing from the lip 7a of the inner lip portion 6a,
This will lead to bearing damage.

In addition, in the above bearing, the outer seal 4 is attached to the housing 1, and the slinger 8 is attached to the shaft 2 and the inner ring retainer 2a, so the structure around the bearing is complicated, and the bearing is attached during assembly. There is a problem in that a separate process is required, and the overall number of assembly steps increases.

Further, the outer seal 4 includes a lip 7a of the inner ring lip portion 6a.
is brought into contact with the outer circumferential surface of the shoulder of the shaft 2 and the outer circumferential surface of the inner ring holder 2a, which requires the troublesome work of grinding these sliding surfaces to achieve a predetermined precision. .

Furthermore, since the axial distance between the pair of external seals 4 is large, a large amount of grease is sealed in the external seals 4, which is a cause of high costs.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems, simplify the seal structure of a rolling bearing sealed by a multiple seal mechanism, and provide a sealing device that is easy to assemble.

[Failure to solve the problem]

The sealing device of the present invention includes an inner seal mounted on an outer ring on at least one shaft end side of a rolling bearing and an outer seal attached to the inner ring.

The inner seal is attached by fitting the outer mounting portion to the inner circumferential surface of the outer ring. A lip portion is provided to be connected to the mounting portion, and between the outer circumferential side and the inner circumferential side, there is a cylindrical portion extending axially outward from the inner seal, and a cylindrical portion that is bent radially outward from the edge of the cylindrical portion. An intermediate lip portion made of an elastic body having a lip portion is provided.

The outer seal is attached by fitting the inner circumferential mounting part to the outer circumferential surface of the inner ring, and between the inner circumferential side and the outer circumferential side, there is a seal that connects to the mounting part axially outward and radially outward. A middle step portion is provided that is located radially outwardly from the middle lip portion of the inner seal and extends axially inwardly through the annular portion,
On the outer circumferential side, an inclined part is provided that extends obliquely outward in the axial direction by turning from the intermediate position or the axially inner edge of the middle step part.

The lip portion of the main lip portion of the inner seal contacts the outer circumferential surface of the inner ring or the outer circumferential surface of the mounting portion of the outer seal to form an inner seal portion, and the lip portion of the intermediate lip portion contacts the outer circumferential surface of the inner ring or the outer circumferential surface of the mounting portion of the outer seal, and the lip portion of the intermediate lip portion contacts the outer circumferential surface of the inner ring or the outer circumferential surface of the mounting portion of the outer seal. The intermediate seal part is in contact with the inner circumferential surface of the outer ring or with a slight gap therebetween, and the 1st I oblique part of the outer seal is in contact with the inner circumferential surface of the outer ring or the inner circumferential surface of the mounting part of the inner seal. Alternatively, the outer peripheral side seal portion is formed with a slight gap between them.

Of the space surrounded by the inner seal and the outer seal and defined between the outer ring and the inner ring, a small space (both on the inner peripheral side of the intermediate lip portion of the inner seal) is filled with grease.

(Function) In the sealing device of the present invention, muddy water etc. on the outside of the bearing is absorbed into the inside by the outer circumferential side seal portion that is constructed between the inclined portion of the outer seal and the inner circumferential surface of the outer ring or inner seal mounting portion. Intrusion is prevented.

The muddy water, etc. that has entered through this outer seal part accumulates in the space formed between the middle lip part of the inner seal and the middle part of the outer seal, and further accumulates in the space formed between the middle lip part of the inner seal and the middle part of the outer seal. Intrusion into the interior is prevented by an intermediate seal portion configured between the lip portion and the inner circumferential surface of the middle portion of the outer seal.

Even if muddy water, etc. accumulated in this space passes through the intermediate seal part and enters, there will be no leakage between the lip part of the main lip part of the inner seal and the outer peripheral surface of the inner ring or outer seal mounting part. Intrusion into the interior is prevented by the inner peripheral side seal portion.

Grease is filled in the inner space of the intermediate lip of the inner seal, so muddy water, etc. that may pass through the intermediate seal and enter the inner space of the intermediate lip is limited to a small amount. be done.

In addition, the intermediate lip portion consists of a cylindrical portion and a lip portion whose tip extends outward in the radial direction, and has a horizontal cross-section, so that muddy water etc. that has accumulated on the outer circumferential side of the intermediate lip portion can be removed.
The intermediate lip portion plays the role of M, making it easier to flow toward the outer seal portion.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings.

FIG. 1 is a longitudinal cross-sectional side view of the hip half showing a first embodiment of the present invention.

In the bearing in this embodiment, both ends of the outer ring 10 and the inner ring 20 in the axial direction are wide bearings extending outward in the axial direction, and the bearing itself has an inner seal 40 and an outer seal 50. It is assembled.

In addition, in the same figure, the symbol l is a housing, 1a is a retaining ring for fixing the outer ring, 2 is a shaft, 2a is an inner ring holder 30 is a ball, 31
indicate the cage, respectively.

A circumferential groove 11 for mounting an inner seal is formed on the inner circumferential surface of the outer ring 1O that is axially inner than both end surfaces of the outer ring 10, and a circumferential groove 11 for mounting an inner seal is formed on the outer circumferential surface of the inner ring 20 that is axially inner than both end surfaces of the inner ring 20. A slope portion 21 is formed.

On the inner circumferential surface of the outer ring 10 that is axially outer than the circumferential groove 11, a large diameter part 13 for sliding contact with the outer seal is formed as a cylindrical surface via a medium diameter part 12. A small diameter portion 23 for attaching an outer seal is formed as a cylindrical surface on the outer circumferential surface on the outer side in the direction.

The inner seal 40 includes an annular portion (core bar) 41 made of a metal body.
The outer circumferential side, the inner circumferential side, and the intermediate portion thereof are respectively made of an elastic body such as rubber or synthetic resin, and have a mounting portion 42 and a main lip portion 44.
, and the intermediate lip portion 47.

An auxiliary lip 43 is provided on the outer circumferential surface of the mounting portion 42 of the inner seal 40, which branches diagonally outward in the axial direction via an annular groove. The main lip part 44 has a lip part 45 on its inner peripheral edge that extends diagonally inward on the outside in the axial direction, that is, in a direction to prevent muddy water from entering, and a lip part 45 that branches from the outer peripheral side of the main lip part 44 and extends diagonally inward in the axial direction. An auxiliary lip 46 extending diagonally inward is provided. Further, the intermediate lip portion 47 is provided with a cylindrical or conical cylindrical portion 48 extending axially outward from the inner seal 40 and a lip portion 49 bent radially outward from its axially outer edge. ing.

The outer seal 50 includes a cylindrical mounting portion 52 on the inner peripheral side and an annular portion 53 that is connected to the axially outer edge of the mounting portion 52 and bent radially outward.
The outer circumferential side of 3 is integrated with a middle section 54 and a main lip section 57 made of an elastic material such as rubber or synthetic resin. A portion of the outer seal 50 that opposes the inner seal 40 in the axial direction is located on the outer side in the axial direction.

The middle portion 54 of the outer seal 50 includes a cylindrical portion 55 extending axially inward and obliquely outward from the outer circumferential edge of the annular portion 53, and a lip portion 56 bending radially outward from the axially inner edge of the cylindrical portion 55. It is provided. At the intermediate position of this middle section 54,
A main lip portion (slanted portion) 57 is provided which extends obliquely outward in the axial direction, that is, in a direction to prevent muddy water from entering through a bent portion extending outward in the radial direction, and the outer peripheral edge thereof is the lip portion. It is part 58.

The above-mentioned inner seal 40 and outer seal 50 are constructed by fitting the respective mounting portions 42 and 52 into the circumferential groove 11 of the outer ring 10 and the small diameter portion 23 of the inner ring 20, so that the respective constituent parts can be placed between each other at a predetermined distance. It is now assembled with the relative positions maintained.

The auxiliary lip 43 of the attachment part 42 of the assembled inner seal 40 contacts the medium diameter part 12 of the outer ring lO axially outward to form a contact type seal part on the outer peripheral side, and the main lip part 44 The lip portion 45 extends axially outward toward the inner ring 2.
The auxiliary lip 46 of the main lip portion 44 is in contact with the slope portion 21 of the inner ring 20 to form a contact-type inner circumferential side seal portion, and the auxiliary lip 46 of the main lip portion 44 approaches the shoulder of the inner ring 20 with a slight gap in the axially inward direction. The intermediate lip portion 47 is located on the inner circumferential side of the middle portion 54 of the outer seal 50, and the lip portion 49 thereof is on the inner circumferential surface of the middle portion 54 of the outer seal 50. They are close to each other with a slight gap between them, and form a non-contact type intermediate seal between the outer circumferential side and the inner circumferential side.

Additionally, the lip portion 5 of the main lip portion 57 of the outer seal 50
8 contacts the large diameter portion 13 of the outer ring 10 toward the outside in the axial direction to constitute a contact type outer circumferential side seal portion, and the lip portion 56 of the middle step portion 54 contacts the large diameter portion 13 of the outer ring 10 slightly. A non-contact type seal portion is formed adjacent to each other with a gap of 100 mm between them.

Between the outer ring 10 and the inner ring 20 that are sealed by the inner seal 40 and the outer seal 50 that constitute the seal portion as described above, there is a middle part 54 of the outer seal 50 and the inner seal 4.
A space 6 divided into three by an intermediate lip 47 of 0
0.61.62 are formed in communication with each other. Grease is sealed in these spaces 60, 61, 62, and this grease is applied to the outside of the bearing by the outer seal portion of the main lip portion 57 of the outer seal 50 that is in sliding contact with the large diameter portion 13 of the outer ring 10. leakage is prevented.

The intermediate portion 54 of the outer seal 50 and the intermediate lip portion 47 of the inner seal 40 in the space portions 61 and 62 each have a function as a foreign matter reservoir such as muddy water.

In the bearing configured as described above, the auxiliary lip 46 on the inner peripheral side of the inner seal 40 has the function of guiding the lubricating grease sealed inside the inner seal 40 toward the balls 30 and flowing it to the outside of the bearing. The leakage of this grease to the outside of the bearing is also prevented by the contact-type inner peripheral side seal portion between the main lip portion 44 and the inner ring 20.

When this bearing is used, for example, in a place where there is a large amount of muddy water, the muddy water is shaken off by the centrifugal force of the main lip portion 57 of the outer seal 50 extending diagonally outward in the axial direction, and the large amount of the outer ring 10. Intrusion into the inside of the bearing is prevented by the outer peripheral side seal portion of the main lip portion 57 that is in sliding contact with the diameter portion 13.

Even if muddy water tries to pass through this outer seal part, the spaces 60 and 61 between the outer seal 50 and the inner seal 40
．． Since grease is sealed in the seal 62, only a small amount of muddy water can enter the outer seal 5.
This will accumulate in a space (reservoir) 60 formed by the middle section 54 of 0. Since the lip portion 56 of the middle portion 54 forms a non-contact type seal portion with the middle diameter portion 12 of the outer ring 10, this accumulated mud water passes through this seal portion by 1tllll to the inner peripheral side. Since the auxiliary lip 43 of the mounting portion 42 of the inner seal 40 slides against the inner diameter portion 12 of the outer ring 10 to form a contact type seal portion, this seal portion prevents the inside of the bearing from leaking. will be prevented from entering.

Even if this accumulated muddy water passes through the seal part formed by the middle part 54 of the outer seal 50, a space (pool part) 61 is formed on the inner circumferential side by the middle lip part 47 of the inner seal 40. , the liquid will accumulate in this space (reservoir) 61 again, and the lip portion 49 of the intermediate lip portion 47 will form a non-contact type seal portion between it and the intermediate portion 54 of the outer seal 50. Because of this structure, leakage to the inner circumferential side through this seal portion is prevented.

Further, this accumulated mud water passes through the seal portion formed by the intermediate lip portion 47 of the inner seal 40 and enters the space portion 62 on the inner peripheral side thereof.
Even if it leaks into the bearing, it is prevented from entering the inside of the bearing because a contact-type inner peripheral side seal part is formed between the main lip part 44 of the inner seal 40 and the inner ring 20.

FIG. 2 is a vertical cross-sectional side view of the upper half of a second embodiment of the invention.

Since this embodiment is also an application of the present invention to the deep groove ball bearing shown in FIG. 1, the same parts are designated by the same reference numerals.

The inner seal 40 is assembled to the large diameter portion 13 formed on the inner circumferential surface of the portion extending outward in the axial direction from both ends of the outer ring 10, and the small diameter portion formed on the outer circumferential surface of the extending portion of the inner ring 20. An outer seal 50 is assembled to 23.

The inner seal 40 includes a planar annular portion 41 and a mounting portion 42 on the outer circumferential side of which are integrally molded from a metal body.
2 has a cylindrical shape extending outward in the axial direction of the annular part 41 in parallel with the axial direction, and the inner peripheral side and the middle of the annular part 41 are respectively made of a main lip part 44 and an intermediate lip made of an elastic body such as rubber or synthetic resin. The main lip part 44 of the inner seal 40, which is integral with the part 47, is configured as a lip part 45 that extends obliquely inward on the outside in the axial direction, that is, in a direction that prevents muddy water from entering. Lip part 4
7 includes a cylindrical or conical cylindrical portion 48 extending axially outward from the inner seal 40, and a diagonally outer portion extending axially inward through a portion bent radially outward from the axially outer end edge of the cylindrical portion 48. That is, a lip portion 49 extending in a direction to prevent muddy water from entering is provided.

The outer seal 50 is made of a metal body, and has an annular portion 53 bent radially outward connected to an axially outer edge of a cylindrical mounting portion 52 on the inner circumferential side. A middle section 54 extending substantially parallel to the axial direction is provided on the outer circumferential side, and a section is provided on the outer peripheral side of the middle section 54 by turning axially outward from the axially inner edge of the middle section 54 and extending obliquely outward, that is, in a direction to prevent muddy water from entering. An extending inclined portion 57 is provided.

The above-mentioned inner seal 40 and outer seal 50 have respective mounting portions 42 and 52 attached to the large diameter portion 13 of the outer ring 10 and the inner ring 20.
By fitting into the small diameter portion 23 of the holder, the respective constituent parts are assembled with each other maintaining a predetermined relative position.

The main lip portion 44 of the assembled inner seal 40 contacts the outer circumferential surface of the mounting portion 52 of the outer seal 50 toward the outside in the axial direction to constitute a contact-type inner circumferential side seal portion, and the intermediate lip portion 47 is located on the inner peripheral side of the middle stage part 54 of the outer seal 50, and its lip part 49 contacts the inner peripheral surface of the middle stage part 54 of the outer seal 50 axially inward, thereby forming a contact type intermediate seal. It makes up the department.

Further, the outer circumferential edge of the inclined portion 57 of the outer seal 50 is close to the inner circumferential surface of the mounting portion 42 of the inner seal 40 with a slight gap therebetween, thereby forming a non-contact outer circumferential side seal portion.

Between the outer ring 10 and the inner ring 20, which are sealed by the inner seal 40 and the outer seal 50 that constitute the seal portion as described above, there is a gap between the outer circumference side and the inner circumference side by the intermediate lip part 47 of the inner seal 40. Space portions 61 and 62 are formed.

The intermediate lip portion 47 of the inner seal 40 within the space portion 61 on the outer peripheral side also has a function as a foreign matter reservoir such as muddy water. Grease is sealed in the space 62 on the inner peripheral side, and this grease is applied to the intermediate lip portion 4 of the inner seal 40 that slides into the middle portion 54 of the outer seal 50.
The intermediate seal section 7 prevents leakage to the outside of the bearing.

In the bearing configured as described above, the lubricating grease sealed inside the inner seal 40 is applied to the inner peripheral side seal portion of the contact type between the main lip portion 44 of the inner seal 40 and the mounting portion 52 of the outer seal 50. This prevents leakage to the outside of the bearing.

Even when this bearing is used, for example, in a place where there is a large amount of muddy water, the shaking action due to the centrifugal force of the inclined portion 57 of the outer seal 50 extending obliquely outward in the axial direction can be applied, as in the above embodiment. The outer peripheral edge of the inclined portion 57 and the inner seal 4
The non-contact type outer circumferential side seal formed between the bearing and the mounting portion 42 prevents muddy water from entering from outside the bearing.

Even if muddy water passes through this outer seal portion, the muddy water that has entered will be absorbed into the intermediate lip portion 4 of the inner seal 4o.
7, and the lip portion 49 of the intermediate lip portion 47 forms the intermediate portion 5 of the outer seal 50.
4 to form a contact-type intermediate seal portion, leakage to the inner peripheral side through this seal portion is prevented.

Even if this accumulated muddy water tries to pass through the seal part formed by the intermediate lip part 47 of the inner seal 40, the space part 6 on the inner peripheral side
2 is filled with grease, so only a small amount of muddy water can enter. The muddy water that has leaked into the inner space 62 is channeled into the inside of the bearing by the contact-type inner seal formed between the main lip 44 of the inner seal 40 and the mounting portion 52 of the outer seal 50. intrusion is prevented.

FIG. 3 is a vertical cross-sectional side view of the upper half of a third embodiment of the present invention.

In this embodiment, an inner seal 40 and an outer seal 50 similar to those of the second embodiment are assembled.
The axial length of the mounting portion 42 of the inner seal 40 and the mounting portion 52 of the outer seal 50 is shorter than that in the second embodiment, and the main lip portion 44 of the inner seal 40 is longer than that of the inner ring 20.
The inclined part 57 of the outer seal 50 is in contact with the outer peripheral surface (small diameter part) 23 of the outer ring 10 to form an inner peripheral side seal part, and the inclined part 57 of the outer ring 10 is close to the inner peripheral surface (large diameter part) 13 of the outer ring 10 with a slight gap therebetween. This constitutes an outer seal portion.

The configurations other than those described above are the same as those of the second embodiment, and their functions are also the same, so the same parts will be denoted by the same reference numerals and repeated explanations will be omitted.

FIG. 4 is a vertical cross-sectional side view of the upper half of the fourth embodiment of the present invention.

In this embodiment, an inner seal 40 and an outer seal 50, which have the same structure as the second embodiment, are assembled on both axial ends of a bearing sealed by an inner seal 3.

Similar to the inner seal of the first embodiment, the inner seal 3 has an annular core metal 3'', a mounting portion 3d made of an elastic material such as rubber or synthetic resin, and a main lip portion 3a, which are arranged on the outer circumference and the inner circumference, respectively. It is integrated with the sides.

An auxiliary lip 3e that branches outward in the axial direction via an annular groove is provided on the outer circumferential surface of the mounting portion 3d of the internal seal 3. A lip portion 3b extending in a direction to prevent intrusion and an auxiliary lip 3C extending diagonally inward in the axial direction are provided.

This internal seal 3 is assembled by fitting its mounting portion 3d into the circumferential groove 11 of the outer ring IO, and the auxiliary lip 3e of the mounting portion 3d is oriented outward in the axial direction to form the inner diameter portion 12 of the outer ring IO.
The lip portion 3b of the main lip portion 3a contacts the slope portion 21 of the inner ring 20 toward the outside in the axial direction to form a contact type seal portion on the inner peripheral side. The auxiliary lip 3C of the main lip portion 3a approaches the shoulder of the inner ring 20 with a slight gap inward toward the axial direction, thereby forming a non-contact type seal portion.

Since the structure and assembly of the inner seal 40 and the outer seal 50 are the same as in the second embodiment, the same parts will be designated by the same reference numerals and repeated explanation will be omitted.

In this embodiment, the grease is applied not only to the space 62 on the inner peripheral side formed by the inner seal 40 and the outer seal 50, but also to the space 63 formed between the inner seal 3 and the inner seal 40 and the pair of It is also enclosed between the internal seals 3.

According to this embodiment, muddy water outside the bearing is removed from the outer seal 50.
It leaks into the space 62 on the inner circumferential side through the outer seal part formed by the inclined part 57 of the inner seal 40 and the intermediate seal part formed by the intermediate lip part 47 of the inner seal 40, and leaks into the inner circumferential side seal part formed by the main lip part 44 of the inner seal 40. Even if an attempt is made to pass through the side seal part, the amount of grease that can enter is limited to a very small amount by the grease sealed in the space 63 between the inner seal 3 and the inner seal 40, and furthermore, the amount of muddy water that has entered this space 63 is limited to a very small amount. is prevented from entering the inside of the bearing by the seal portion formed by the auxiliary lip 3e on the outer circumferential side of the internal seal 3 and the seal portion formed by the main lip portion 3a on the inner circumferential side.

In each of the above embodiments, the shaft end portions on both the left and right sides of the bearing,
Although we have illustrated and explained the case where a double-structure seal mechanism is provided that combines an inner seal and an outer seal, depending on the type of machine and equipment to which the bearing is installed, the bearing installation position, etc. Only the end side can have a double seal structure according to the present invention.

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

Furthermore, the metal portion of the inner seal may also be coated with rubber or synthetic resin on its front surface.

〔Effect of the invention〕

As explained above, in the sealing device of the present invention, an inner seal having a main lip part and an intermediate lip part is attached to the outer ring on at least one shaft end/side of a rolling bearing, and the inner ring has a middle part and an inclined part. The main lip of the inner seal contacts the inner ring or the mounting part of the outer seal, and the intermediate lip contacts the middle part of the outer seal. In addition, the inclined part of the outer seal forms a contact or non-contact type outer peripheral seal part between the outer ring or the mounting part of the inner seal, and the inner seal Among the spaces defined between the inner and outer rings and surrounded by the outer seal, at least the inner space is filled with grease.

Therefore, in this invention, since the inner seal and the outer seal can be treated as a multi-seal bearing in which the inner seal and the outer seal are integrally assembled inside the bearing, the process of assembling the bearing is simplified, and the assembly process is simplified. It becomes possible to significantly reduce man-hours.

Further, in this invention, the main lip portion of the inner seal,
In other words, the lip part of the sloped part of the outer seal is made to come into sliding contact with the outer circumferential surface of the inner ring and the inner circumferential surface of the outer ring, respectively, so unlike conventional bearings of this type, the shoulder of the shaft, the inner ring presser, etc. The process of grinding is also unnecessary.

In addition, in this invention, since the inner seal and the outer seal are assembled integrally with the bearing, not only the space between these seals becomes narrower, but also the inner seal is provided inside the inner seal. Since the space between the inner seal and the inner seal can be narrowed even in cases where the inner seal is closed, and the distance between the pair of inner seals can be shortened, only a small amount of grease is required to be sealed in these spaces, resulting in low cost. It becomes a cost-effective sealing device.

Furthermore, in the present invention, the bearing has seal portions at three locations: the inner periphery, the outer periphery, and the middle between the inner and outer peripheries, and the lip portion of the inner periphery side seal portion and the inclined portion of the outer periphery side seal portion are aligned at different locations. Since the bearings are also oriented in a direction to prevent muddy water from entering, the amount of muddy water entering into the inside of the bearing is reduced.

Therefore, according to the present invention, the sealing of a rolling bearing has an excellent sealing function due to its multilayer structure, does not require maintenance management such as replenishment of lubricating grease, and has a simple structure and easy assembly. A device is obtained.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional side view showing the upper half of a first embodiment of the invention, FIG. 2 is a longitudinal sectional side view showing the upper half of a second embodiment of the invention, and FIG. FIG. 4 is a vertical side view showing the upper half of the fourth embodiment of the present invention, and FIG. 5 is the upper half of the conventional deep ball bearing sealing device. FIG. In the figure, 10 is an outer ring, 20 is an inner ring, 40 is an inner seal, and 4
2 is a mounting portion of the inner seal, 44 is a main lip portion of the inner seal, 45 is a lip portion thereof, 47 is an intermediate lip portion of the inner seal, 48, 49 is a cylindrical portion thereof, a lip portion, 50
52 is the outer seal, 53 is the mounting part of the outer seal, annular part, 54 is the middle part of the outer seal, 57 is the inclined part of the outer seal, 61.62 is the outer circumferential space of the middle lip of the inner seal, and This is the circumferential space.

Claims (4)

[Claims] (1) In a sealing device that seals at least one shaft end side of a rolling bearing with built-in lubricating grease, the inner seal attached to the shaft end side of the outer ring has an axially outer diagonal inner seal. A main lip part having a lip part made of an elastic body extending in the direction is provided, and a cylindrical part extending axially outward from the inner seal and a cylindrical part between the main lip part and the mounting part on the outer peripheral side are provided. The outer seal is provided with an intermediate lip portion made of an elastic body and has a lip portion bent radially outward from the edge of the portion, and the outer seal is attached to the inner ring and is located axially outer than the inner seal. , a middle portion extending axially inward via an annular portion connected to the axially outer side of the inner circumferential mounting portion and extending radially outwardly is located radially outwardly than the intermediate lip portion of the inner seal; The outer circumferential side is provided with an inclined part that turns from the edge or middle of the middle stage part and extends obliquely outward in the axial direction, and the lip part of the main lip part of the inner seal is formed on the inner ring. Contacting the outer circumferential surface or the outer circumferential surface of the mounting portion of the outer seal to form an inner circumferential seal portion, and the lip portion of the intermediate lip portion contacting the inner circumferential surface of the middle portion of the outer seal, or
Or configure an intermediate seal part with a slight gap,
The inclined portion of the outer seal contacts the inner circumferential surface of the outer ring or the inner circumferential surface of the mounting portion of the inner seal, or forms an outer seal portion with a slight gap, and is surrounded by the inner seal and the outer seal. 1. A sealing device for a rolling bearing, characterized in that, of a space defined between an outer ring and an inner ring, at least a space on the inner peripheral side of an intermediate lip portion of an inner seal is filled with grease. (2) The attachment portion of the inner seal is made of an elastic body, and is provided with an auxiliary lip that branches obliquely outward in the axial direction from the attachment portion and contacts the inner circumferential surface of the outer ring. Sealing device for rolling bearings. (3) Claims 1 or 2 further include an auxiliary lip that branches obliquely inward in the axial direction from the main lip portion of the inner seal and approaches the outer peripheral surface of the inner ring with a slight gap therebetween. Sealing device for rolling bearings as described in . (4) The attachment part and the annular part of the outer seal are made of a metal body, and the middle part made of an elastic body and the inclined part that turns from the middle and contacts the inner circumferential surface of the outer ring are integral with the annular part, Claims 1 to 3 further include a lip portion bent radially outward from the edge of the middle portion and adjacent to the inner circumferential surface of the outer ring with a slight gap therebetween. Sealing device for rolling bearings.