JP2007092793A - Sealed rolling bearing - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sealed rolling bearing having a sliding face of a seal groove with improved quantity of surface irregularities such as roughness and swelling and securing good concentricity and parallelism between a raceway and the seal groove. <P>SOLUTION: This sealed rolling bearing is a seal bearing, and at least an outer peripheral seal groove out of an inner peripheral seal groove and the outer peripheral seal groove has a machined surface. A seal is fixed to the inner peripheral seal groove of an outer ring, and a seal lip provided on the inner peripheral face of the seal is slid with the outer peripheral seal groove of an inner ring. The surface irregularity quantity on the sliding face with the seal lip on the outer peripheral seal groove is set below 2 μm. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a sealed rolling bearing.

  Conventionally, sealed roller bearings are shown, for example, in FIG. 7 (upper half sectional view of the center line XX) and FIG. 8 (Az portion in FIG. 7), FIG. 9 and FIG. Like the double row rolling bearing Hz, the outer ring 1z, the inner ring 2z, the retainer 4z that holds the ball 3z disposed between the inner race 11z of the outer ring 1z and the outer race 21z of the inner ring 2z, and the bearing The sealing seal 5z holds the lubricant G and prevents the entry of foreign matters such as water from the outside.

  In general, the sealing seal 5z is fixed to the inner peripheral sealing groove 15z of the outer ring 1z, and the outer peripheral sealing groove 25z of the inner ring 2z and the sealing lip 51z of the sealing seal 5z are kept in a sliding state, while water from the outside etc. And the leakage of lubricant such as grease G filled inside is prevented.

  Automobile auxiliary equipment (compressor, alternator, etc.) installed in the engine room of the car is driven by a belt for engine rotation, and a sealed roller bearing is used for the idler pulley and tension pulley used for the belt drive. Has been.

  In recent years, due to downsizing, weight reduction, and cost reduction, sealed roller bearings are often exposed to the outside air, and the usage environment has become increasingly severe. In such a case, water may be directly applied to the sealed rolling bearing, and the sealed rolling bearing is required to have more severe water resistance.

When foreign matter such as water or muddy water enters the sealed rolling bearing, problems such as deterioration of grease, deterioration of lubrication performance, and shortening of the bearing life may occur.
In order to improve the water resistance, there are methods such as improving the sealing seal and improving the sliding state between the inner ring and the sealing seal.

  However, the outer ring 1z and the inner ring 2z are heat-treated after the inner circumferential track 11z, the outer circumferential track 21z, the inner circumferential sealing groove 15z, and the outer circumferential sealing groove 25z are formed by turning or forging, respectively. Usually, deformation of the inner ring 2z also occurs.

  Therefore, after the heat treatment, the outer ring 1z and the inner ring 2z perform grinding of each raceway, but the seal grooves 15z and 25z are not subjected to finishing processing such as grinding or turning while being turned or forged. The surface unevenness amount of the sliding surface 251z of the seal groove 25z is not corrected, and the concentricity and parallelism between the tracks 11z and 21z and the seal grooves 15z and 25z are not corrected.

  9 and 10 are enlarged views of the inner peripheral seal groove 15z of the outer ring 1z and the outer peripheral seal groove 25z of the inner ring 2z, but the sliding surface 251z with the seal lip 51z is not processed after heat treatment, so The amount is not improved in a larger numerical state due to deformation due to heat treatment.

  Therefore, the sliding state between the seal lip 51z of the attached seal seal 5z and the sliding surface 251z of the outer peripheral seal groove 25z may not be satisfactory, and it is not possible to meet severe water resistance requirements. There is a fear.

There is a proposal for improving the sliding state (see, for example, Patent Document 1).
JP-A-6-246546

  However, in Patent Document 1, in order to correct the deformation due to the heat treatment of the track, a processing step is performed in which the track and the seal groove are cut after the heat treatment, and then the track is ground.

  However, in order to improve the sealing performance, the concentricity between the raceway and the seal groove is of course good, but further, the amount of surface irregularities such as roughness and undulation of the seal groove is reduced, and the seal lip and It is necessary to improve the sliding state with the sliding surface.

  In patent document 1, it is improvement about concentricity, Comprising: It does not mention about the improvement of surface unevenness amounts, such as the roughness of a seal groove, and a wave | undulation.

  The present invention has been made in view of the above points, and the present invention has a sliding surface of the seal groove with improved surface irregularities such as roughness and undulation, and in addition, the raceway and the seal groove It is an object of the present invention to provide a sealed rolling bearing that ensures good concentricity and parallelism.

In order to achieve the above object, the present invention provides:
An outer ring having an inner circumferential track and inner circumferential sealing grooves at both ends;
An inner ring having an outer peripheral track facing the inner peripheral track and an outer peripheral seal groove facing the inner peripheral seal groove at both ends;
A ball interposed between an inner circumferential track of the outer ring and an outer circumferential track of the inner ring;
In a sealed rolling bearing comprising a hermetic seal that seals a space between the outer ring and the inner ring,
At least the outer peripheral seal groove of the inner peripheral seal groove and the outer peripheral seal groove has a finished surface, the seal seal is fixed to the inner peripheral seal groove of the outer ring, and a seal lip is provided on the inner peripheral surface of the seal seal. The seal lip slides with the finished surface of the outer peripheral seal groove of the inner ring, and the surface unevenness of the finished surface, which is a sliding surface sliding with the seal lip, is 2 μm or less. A sealed rolling bearing is provided.

The present invention also provides:
An outer ring having an inner circumferential track and inner circumferential sealing grooves at both ends;
An inner ring having an outer peripheral track facing the inner peripheral track and an outer peripheral seal groove facing the inner peripheral seal groove at both ends;
A ball interposed between an inner circumferential track of the outer ring and an outer circumferential track of the inner ring;
In a sealed rolling bearing comprising a hermetic seal that seals a space between the outer ring and the inner ring,
Of the inner peripheral seal groove and the outer peripheral seal groove, at least the inner peripheral seal groove has a finished surface, the seal seal is fixed to the outer ring seal groove of the inner ring, and a seal lip is provided on the outer peripheral surface of the seal seal. The seal lip slides with the finish surface of the inner peripheral seal groove of the outer ring, and the surface unevenness of the finish surface that becomes a slide surface that slides with the seal lip is 2 μm or less. A sealed rolling bearing is provided.

  According to the present invention, there is provided a sealed roller bearing having a sliding surface of a seal groove with improved surface roughness such as roughness and undulation, and ensuring good concentricity and parallelism between the raceway and the seal groove. Can be provided.

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

(Embodiment 1)
The first embodiment of the present invention will be described with reference to FIGS. 1, 2, 3, and 4.

FIG. 1 is a cross-sectional view of the upper half of the center line XX of the sealed rolling bearing of this embodiment.
Sealed rolling bearing H ₁ of the present embodiment is an outer ring 1, an inner ring 2, balls 3, and holds the lubricant G in the cage 4, and the bearing to hold the ball, and to prevent the entry of foreign objects such as water from the outside It consists of a hermetic seal 5.

  In the following, individual components will be described. Since this embodiment is intended for the axial center line CL, referring to FIGS. 2, 3, and 4 which are enlarged views of the A part in FIG. In the figure, the left side will be mainly described.

  The outer ring 1 has double-row inner circumferential tracks 11 and 11 and inner circumferential sealing grooves 15 and 15 at both ends.

  The inner peripheral seal groove 15 has a plane 151 that is substantially perpendicular to the center line XX from the predetermined position facing the axially outward direction of the inner peripheral surface 12 of the outer ring 1 and a predetermined radial direction of the plane 151. A first cylindrical portion 152 directed axially outward from the position, an inclined surface 153 directed axially outward and radially inward from the first cylindrical portion 152, and a predetermined position of the inclined surface 153 following the inclined surface 153 And a second cylindrical portion 154 heading outward in the axial direction.

After the heat treatment, the inner peripheral track 11 is ground with reference to the inner peripheral surface 12. At this time, the inclined surface 153 or the inclined surface 153 and the flat surface 151 are turned or ground with reference to the inner peripheral surface 12. By applying this to the finished surface, the concentricity of the inclined surface 153 and the parallelism (axial runout) of the plane 151 with respect to the center line XX are improved. (See Fig. 1, Fig. 2, Fig. 3)
The inner ring 2 has outer circumferential tracks 21 and 21 that face the double-row inner circumferential tracks 11 and 11 of the outer ring 1, and outer circumferential seal grooves 25 and 25 at both ends.

  The outer peripheral seal groove 25 is directed from the predetermined position on the outer peripheral surface 22 in the axially outward direction to the radially inner side, and from the predetermined position on the first inclined surface 251 in the radial direction to the axially outward direction. The first cylindrical surface 252, the second inclined surface 253 that faces axially outward and radially outward from the first cylindrical surface 252, and the second inclined surface 253 following the second inclined surface 253 from the predetermined position toward the axially outward direction. Two cylindrical surfaces 254. The first inclined surface 251 is formed as an inclined surface that is substantially perpendicular to the center line XX.

  After the heat treatment of the inner ring 2, the outer peripheral race 21 is ground. At this time, the first inclined surface 251 of the outer peripheral seal groove 25 is finished by grinding or turning with respect to the outer peripheral race 21 or the outer peripheral surface 22. The surface is finished with a surface irregularity of 2 μm or less. Therefore, the amount of surface unevenness due to the roughness and undulation of the first inclined surface 251 is reduced, and the concentricity and parallelism (axial deflection) of the first inclined surface 251 with respect to the center line XX are improved. .

  In the present embodiment, as will be described later, in particular, the first inclined surface 251 is a sliding surface with the seal lip 51. Therefore, the first inclined surface 251 is a finished surface by grinding or turning, and the roughness, undulation, and inner circumference of the sliding surface It is necessary to reduce the degree of parallelism (axial deflection) with respect to the track 11.

  In the present embodiment, both the inner peripheral seal groove 15 of the outer ring 1 and the outer peripheral seal groove 25 of the inner ring 2 are preferably subjected to grinding or turning after heat treatment. Finishing may be applied only to the first inclined surface 251 of the inner ring 2 that forms the surface (see FIGS. 1, 2, and 4).

  In the present embodiment, as described above, the inner ring 2 has the first inclined surface 251 as the finished surface, but the seal lip 51 of the seal seal 5 is not limited to the first inclined surface 251, for example, the second In the case of a hermetic seal having another type of sealing lip that also slides with the cylindrical surface 254, the second cylindrical surface 254 is also implemented as a finished surface.

  The hermetic seal 5 includes a cored bar 52 and an elastic body 53 such as rubber that is baked around the cored bar 52 by a vulcanization process. The hermetic seal 5 includes a fixing portion 54 on the outer peripheral side of the elastic body 53. Has a seal lip 51.

  The cored bar 52 is composed of a cylindrical portion 521 and a flange portion 522 bent at a right angle inward in the radial direction from a predetermined position of the cylindrical portion 521, and the side that becomes the outer surface when the sealing seal 5 is attached to the rolling bearing (the antiball The elastic body 53 is mainly baked on the side).

  A fixing portion 54 is formed on the outer side in the radial direction of the cylindrical portion 521 of the core metal 52.

  A seal lip 51 is formed radially inward of the flange portion 522.

  The seal lip 51 includes a first radial lip 511, a second radial lip 512, and an axial lip 513.

  The ball 3 is held by a cage 4 and is interposed between the outer ring 1 and the inner ring 2.

  A predetermined amount of grease G is sealed inside the bearing.

  Next, a state in which the hermetic seal 5 is incorporated in the rolling bearing will be described.

  The fixing portion 54 of the hermetic seal 5 is fixed to the inner peripheral seal groove 15 of the outer ring 1.

  The first radial lip 511 and the second radial lip 512 of the seal lip 51 form a labyrinth clearance with the second cylindrical surface 254 of the outer peripheral seal groove 25 and the outer peripheral surface 22 of the inner ring 1 and do not slide.

  The axial lip 513 has the first inclined surface 251 as a sliding surface, but the first inclined surface 251 is a finished surface by grinding or turning, and the surface unevenness is small, so that the sliding state is good.

  Since the contact state between the axial lip 513 and the first inclined surface 251 is good as described above, it is possible to achieve high sealing, the wear of the axial lip 513 is small, and the raceway grooves between the first inclined surface 251 and the inner ring 2 are further reduced. 21 has good concentricity and parallelism (shaking in the axial direction), the contact pressure between the seal lip 51 and the first inclined surface 251 is constant in the circumferential direction, and further, the first inclined surface 251 is concentric. Since the value of degree and parallelism is small, torque fluctuation during one rotation of the bearing can be suppressed.

  The space of the outer peripheral seal groove 25 surrounded by the first radial lip 511 and the axial lip 513 is a space necessary as a storage space when foreign matter enters from the outside or when a lubricant such as grease leaks from the inside.

Next, the first inclined surface 251 of the peripheral sealing groove 25 of the inner ring 2 only (sliding surface) produced a bearing H ₁ rolling seal was finished surface by turning, Comparative Experiment Comparative Example which is not turning The results are shown below.
The inner peripheral seal groove 15 of the outer ring 1 is not finished.

Evaluation bearing: Double-row rolling bearing (double-row angular contact ball bearing)
Bearing specifications: Inner diameter: 35mm, Outer diameter: 52mm, Width: 20mm
Test content: Measurement of water intrusion when rotating in water for a certain period of time Test results:

Amount of water intrusion of the first inclined surface of the first inclined surface Presence or absence of turning Surface unevenness (μm)
No 19 0,05
32 0,52
28 0, 18
17 0,07
Yes 2 0:00
1 0,01
2 0,01
2 0,01
1 0:00
(Ii) The surface unevenness of the sliding surface is the maximum surface unevenness on the circumference including roughness and undulation, and is the larger value of the sliding surfaces on both sides.

After the heat treatment, the sliding surface of the inner ring 2 (the first inclined surface 251 in this embodiment) and the flat surface 151 and the inclined surface 153 of the inner peripheral seal groove 15 of the outer ring 1 for fixing the fixing portion 54 of the seal seal 5 are ground or turned. Although it is best to machine it to a finished surface, it has been found that a sufficient effect can be obtained even when turning only the sliding surface (first inclined surface 251) of the inner ring 2 if the surface unevenness is 2 μm or less. This is because the axial lip 513 and the first inclined surface 251 have a smaller contact area than that of the fixed portion 54 and are in dynamic contact with each other, and thus have a large influence on the sealing performance.

  Therefore, in this embodiment, the effect was confirmed only by processing the surface unevenness amount of the first inclined surface 251 sliding with the axial lip 513 to 2 μm or less. Finishing by processing may not be performed, but in addition to the first inclined surface 251 of the inner ring 2 being a finished surface, the inner circumferential seal groove 15 of the outer ring 1 is made a finished surface to achieve concentricity and parallelism. The degree can be improved and further effects can be achieved.

  Since there are types other than the type of hermetic seal shown in the present embodiment, the part to be finished can be determined based on the specifications of the hermetic seal, and a suitable sliding state can be obtained.

  These finishing processes can be performed without problems if a forming tool or a forming grindstone is used.

In the above description, a double row rolling bearing is used, but FIG. 5 shows a case where it is implemented in a single row rolling bearing H ₂ as a modification.

This modification is an example of changing the double row rolling bearing H ₁ of the first embodiment to the single row rolling bearing H _2, a description thereof will be omitted redundant with respect to other parts, as well as codes.

(Embodiment 2)
Next, the sliding surfaces of the sealing seal 5 on the inner peripheral seal groove 15 of the outer ring 1 is provided, the sealing rolling bearing H ₃ for fixing the fixing portion 54 of the hermetic seal 5 in the outer circumference seal groove 25 of the inner ring 2 in FIG. 6 Show.

  In the first embodiment described above, the outer peripheral seal groove 25 of the inner ring 2 is provided with a sliding surface with the seal seal 5, but in the second embodiment, the outer peripheral seal groove 25 of the inner ring 2 is used as the inner peripheral seal of the outer ring 1 in the first embodiment. Formed in the shape of the groove 15 to serve as a fixing portion of the seal seal 5, the inner peripheral seal groove 15 of the outer ring 1 is formed in the same shape as the outer peripheral seal groove 25 of the inner ring 2 of the first embodiment, and slides with the seal lip 51. Provide a surface.

  The hermetic seal 5 is configured such that the inner peripheral side is a fixing portion 54 to the inner ring 2 and the outer peripheral side is a seal lip 51.

  The first embodiment has a relationship in which the functions of the outer ring 1 and the inner ring 2 are replaced in the relationship with the hermetic seal.

The upper half sectional view explaining Embodiment 1 of the present invention is shown. The principal part of Embodiment 1 is shown. The principal part of the outer ring | wheel of Embodiment 1 is shown. The principal part of the inner ring of Embodiment 1 is shown. The modification of Embodiment 1 is shown. The upper half sectional view explaining Embodiment 2 of the present invention is shown. It is an upper half sectional view explaining a conventional example. FIG. 8 is a partial explanatory diagram of FIG. 7. An explanatory view of an outer ring of a conventional example is shown. An explanatory view of an inner ring of a conventional example is shown.

Explanation of symbols

H ₁ , H ₂ , H ₃ : Sealed rolling bearing 1: Outer ring 11: Inner circumferential track 12: Inner circumferential surface 13: Outer circumferential surface 15: Inner circumferential sealing groove 151: Plane 152: First cylindrical portion 153: Inclined surface 154: Second cylindrical portion 2: Inner ring 21: Outer raceway 22: Outer peripheral surface 25: Outer peripheral seal groove 251: First inclined surface 252: First cylindrical surface 253: Second inclined surface 254: Second cylindrical surface 3: Ball 4: Holding 5: Sealing seal 51: Sealing lip 511: First radial lip 512: Second radial lip 513: Axial lip 52: Core metal 521: Cylindrical part 522: Flange part 53: Elastic body 54: Fixing part G: Grease

Claims (2)

An outer ring having an inner circumferential track and inner circumferential sealing grooves at both ends;
An inner ring having an outer peripheral track facing the inner peripheral track and an outer peripheral seal groove facing the inner peripheral seal groove at both ends;
A ball interposed between an inner circumferential track of the outer ring and an outer circumferential track of the inner ring;
In a sealed rolling bearing comprising a hermetic seal that seals a space between the outer ring and the inner ring,
At least the outer peripheral seal groove of the inner peripheral seal groove and the outer peripheral seal groove has a finished surface, the seal seal is fixed to the inner peripheral seal groove of the outer ring, and a seal lip is provided on the inner peripheral surface of the seal seal. The seal lip slides with the finished surface of the outer peripheral seal groove of the inner ring, and the surface unevenness of the finished surface, which is a sliding surface sliding with the seal lip, is 2 μm or less. Sealed rolling bearing. An outer ring having an inner circumferential track and inner circumferential sealing grooves at both ends;
An inner ring having an outer peripheral track facing the inner peripheral track and an outer peripheral seal groove facing the inner peripheral seal groove at both ends;
A ball interposed between an inner circumferential track of the outer ring and an outer circumferential track of the inner ring;
In a sealed rolling bearing comprising a hermetic seal that seals a space between the outer ring and the inner ring,
Of the inner peripheral seal groove and the outer peripheral seal groove, at least the inner peripheral seal groove has a finished surface, the seal seal is fixed to the outer ring seal groove of the inner ring, and a seal lip is provided on the outer peripheral surface of the seal seal. The seal lip slides with the finish surface of the inner peripheral seal groove of the outer ring, and the surface unevenness of the finish surface that becomes a slide surface that slides with the seal lip is 2 μm or less. Sealed rolling bearing.

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