JP2006258131A - Rolling bearing - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rolling bearing which has a superior waterproofness and dustproofness without increasing a slide-contact torque of a seal lip and is manufactured at low costs. <P>SOLUTION: The rolling bearing 10 has a sealing unit 15 which provides an annular metal core 16 and an annular elastic member 17 fixed on the metal core 16. The elastic member 17 has the main seal lip 17b which is projected from its inner peripheral edge to an inward axial direction and is in slide-contact with a seal groove 12b arranged on an edge of an inner ring 12, and the auxiliary seal lip 17e which is prepared more outward than the main seal lip 17b in a radial direction and is in slide-contact with a side face 22a of an annular member 22 coaxially arranged with an inner ring 12. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a rolling bearing, and more particularly to a rolling bearing suitable for supporting a rotating shaft of a vehicular auxiliary machine such as an automobile exposed to foreign matter such as muddy water and dust.

  For example, an automobile auxiliary machine such as an alternator uses an engine as a drive source, and an endless belt or the like is provided between a drive pulley fixed to the crankshaft of the engine and a driven pulley fixed to a rotating shaft of the automobile auxiliary machine. The winding transmission member is wound and driven. Rolling bearings that are used in automobile auxiliary equipment such as alternators are often used in poor environments where foreign matter such as water, muddy water, and dust from the road surface scatters around. This is one of the factors that cause problems in rotation by entering the bearing. Also, the alternator is provided with a metal brush for rectifying current in the vicinity of the rolling bearing, so wear powder generated from the metal brush enters the rolling bearing and abnormally wears the rotating shaft and the rolling bearing. There was a fear.

  As shown in FIG. 3, a conventional rolling bearing 100 used for an alternator or the like includes an outer ring 101, an inner ring 102, and a plurality of balls 103 that are rotatably arranged between the outer ring 101 and the inner ring 102, And a sealing device 104 that seals between the outer ring 101 and the inner ring 102. In the sealing device 104, the outer peripheral edge 104a is fixed to the engaging groove 101a at the end of the outer ring 101, and the seal lip 104b formed at the inner peripheral edge is formed at the outer peripheral surface end of the inner ring 102. 102a is disposed in sliding contact with 102a. In addition, an annular slinger (draining plate) 106 that rotates adjacent to the inner ring 102 and rotates together with the rotation shaft 105 is disposed on the rotation shaft 105. The rolling bearing 100 prevents the intrusion of foreign matter into the rolling bearing 100 by the sealing function of the sealing device 104 and the draining function of the slinger 106, thereby making the rolling bearing 100 waterproof and dustproof.

In addition, the rolling bearing 110 shown in FIG. 4 forms a main seal lip 111a on the inner peripheral edge of the sealing device 111 and an auxiliary seal lip 111b on the outer surface near the main seal lip 111a. The main seal lip 111a is in sliding contact with the seal groove 102a of the inner ring 102, and the auxiliary seal lip 111b is disposed close to the seal groove 102a, so that the rolling bearing 110 is waterproof and dustproof (see, for example, Patent Document 1). .
Japanese Patent Laid-Open No. 2001-200857 (page 3-4, FIG. 1)

  However, the conventional rolling bearing 100 shown in FIG. 3 is designed to be waterproof and dustproof due to the centrifugal force action by the rotation of the slinger 106 and the sealing function of the seal lip 104 b, but between the sealing device 104 and the slinger 106. Since there is a relatively large gap C, foreign matter such as water, muddy water, and dust that has entered through the gap C can easily reach the sliding contact portion between the seal lip 104b and the seal groove 102a, and the waterproof and dustproof properties are not always sufficient. It wasn't.

  Further, the sealing device 111 of the rolling bearing 110 shown in FIG. 4 has a labyrinth seal by providing an auxiliary seal lip 111b close to and opposed to the side surface of the slinger 106 to achieve waterproofing and dustproofing. Since there is still a gap C between the seal lip 111b and the slinger 106, foreign matter can pass through the gap C and reach the sliding contact portion between the main seal lip 111a and the seal groove 102a and enter the rolling bearing 110. There was room for further improvement.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a rolling bearing that can be manufactured at low cost without increasing the sliding contact torque of the seal lip and having excellent waterproofness and dustproofness. There is.

The above object of the present invention can be achieved by the following constitution.
(1) An outer ring having an outer ring raceway surface formed on an inner peripheral surface, an inner ring having an outer ring raceway surface formed on an outer peripheral surface, and a rollable arrangement between the outer ring raceway surface and the inner ring raceway surface. A rolling bearing comprising a plurality of rolling elements and a sealing device whose outer peripheral edge is fixed to an axial end of the outer ring and seals between the outer ring and the inner ring,
The sealing device includes an annular cored bar and an annular elastic member fixed to the cored bar,
The elastic member protrudes inward in the axial direction from an inner peripheral edge thereof, and is provided in a radially outward direction from the main seal lip, and is in slidable contact with a seal groove provided at an end of the inner ring, and A rolling bearing comprising: an auxiliary seal lip slidably contactable with a side surface of an annular member disposed coaxially with the inner ring.
(2) The rolling bearing according to (1), wherein the auxiliary seal lip is disposed on an axially outer side of the cored bar.
(3) The elastic member is formed radially outward from the main seal lip and protrudes inward in the axial direction, and is formed radially outward from the sub seal lip and protrudes inward in the axial direction. The rolling bearing according to (1) or (2), further comprising: a grease lip.
(4) The rolling bearing according to any one of (1) to (3), wherein the annular member is a slinger disposed adjacent to the inner ring and used in an alternator.

  According to the rolling bearing of the present invention, the elastic member of the sealing device includes a main seal lip projecting inward in the axial direction from the inner peripheral edge thereof and slidably in contact with a seal groove provided at an end of the inner ring. An auxiliary seal lip that is slidably contacted with the side surface of the annular member that is provided radially outward and coaxially with the inner ring is provided, so that water, muddy water, and dust are generated by the centrifugal force action of the annular member. Etc. are difficult to reach the main seal lip and have great waterproof and dustproof properties.

  In addition, since the auxiliary seal lip is arranged outward in the axial direction of the core bar, the movement of the auxiliary seal lip due to contact is transmitted to the main seal lip by the core bar having a large mechanical strength, so that the main seal lip is sealed. Stable sealing performance is always given without adversely affecting performance. Further, the auxiliary seal lip is arranged on the outer side in the axial direction of the metal core, so that the auxiliary seal lip is lightly connected to the annular member when the auxiliary seal lip is in strong contact with the annular member at the initial stage of installation of the rolling bearing. Since it wears out until it comes into a contact state, the contact of the auxiliary seal lip hardly affects the main seal lip, and the increase in torque due to the increase of the contact seal lip can be reduced.

Hereinafter, an embodiment of a rolling bearing according to the present invention will be described in detail with reference to the drawings.
As shown in FIGS. 1 and 2, the rolling bearing 10 of the present embodiment is used by being incorporated in an auxiliary machine for an automobile such as an alternator, an outer ring 11 on which a housing 20 is fitted, and a rotary shaft 21. Includes an inner ring 12, a plurality of balls 13 that are rolling elements, a retainer 14, and a sealing device 15.

  An outer ring raceway surface 11 a is formed on the inner peripheral surface of the outer ring 11, and an inner ring raceway surface 12 a is formed on the outer peripheral surface of the inner ring 12. The plurality of balls 13 are arranged to freely roll between the outer ring raceway surface 11a and the inner ring raceway surface 12a, and are held at equal intervals in the circumferential direction by the cage 14. A sealing device 15 (only one is shown in FIG. 1) disposed on both sides of the ball 13 between the outer ring 11 and the inner ring 12 is grease (not shown) enclosed in the rolling bearing 10 outside the rolling bearing 10. And foreign matter (eg, water, muddy water, dust, etc.) outside the rolling bearing 10 is prevented from entering the inside.

  The sealing device 15 includes a cored bar 16 in which a metal plate such as a steel plate is formed in an annular shape, and an annular elastic member 17 fixed to the cored bar 16. The sealing device 15 press-fits the outer peripheral edge portion 17a of the elastic member 17 that covers the outer peripheral edge of the metal core 16 and projects slightly outward in the radial direction into the locking groove 11b formed at the end of the outer ring 11. It is being fixed to the outer ring | wheel 11 by latching by etc. The elastic member 17 extends radially inward from the inner peripheral edge of the cored bar 16, and a main seal lip 17b protruding inward in the axial direction is formed at the inner peripheral edge. The main seal lip 17 b is in sliding contact with the side wall surface 12 c of the seal groove 12 b provided at the end of the inner ring 12. Further, the elastic member 17 is further formed with an auxiliary seal lip 17c and a grease lip 17d projecting inward in the axial direction on the inner surface radially outward from the main seal lip 17b, and close to the side wall surface 12c of the seal groove 12b. Opposed to each other.

  Further, the elastic member 17 is formed with an auxiliary seal lip 17e protruding outward in the axial direction on the outer side surface 16a of the cored bar 16 on the outer side in the radial direction from the main seal lip 17b. The auxiliary seal lip 17e is fixed to the rotary shaft 21, is coaxial with the inner ring 12, and is in sliding contact with the side surface 22a of the slinger 22 that is an annular member disposed adjacent to the inner ring 12.

  The operation of the rolling bearing 10 of this embodiment will be described. 1 and 2, the rolling bearing 10 is sealed by two locations, a main seal lip 17 b that is in sliding contact with the seal groove 12 b and an auxiliary seal lip 17 e that is in sliding contact with the slinger 22. The rolling bearing 10 is also waterproof and dustproof by the centrifugal force action of the slinger 22. That is, foreign matter adhering to the outer surface of the rotating slinger 22 is removed radially outward of the slinger 22 by centrifugal force acting on the foreign matter, and foreign matter such as water, muddy water, and dust outside the rolling bearing 10. Is prevented from entering by the auxiliary seal lip 17e slidably contacting the slinger 22, and reaching the slidable contact portion between the main seal lip 17b and the seal groove 12b is prevented. Even if foreign matter enters beyond the auxiliary seal lip 17e, the foreign matter is further prevented from entering the rolling bearing 10 by the main seal lip 17b slidably contacting the seal groove 12b.

  Further, since the sub seal lip 17c and the grease lip 17d form a labyrinth seal with the side wall surface 12c of the seal groove 12b that is close to each other, the labyrinth seal by the sub seal lip 17c is the same as the main seal lip 17b and the seal lip 17d. The foreign matter that has passed through the sliding contact portion of the groove 12 b is prevented from reaching the inside of the rolling bearing 10. Further, the labyrinth seal by the grease lip 17d prevents the grease filled in the rolling bearing 10 from leaking.

  Since the auxiliary seal lip 17e is disposed and firmly supported on the core bar 16 having a high mechanical strength, for example, the tightening margin of the auxiliary seal lip 17e is large at the initial installation of the slinger 22, and the auxiliary seal lip 17e slides strongly against the slinger 22. When contacting, the auxiliary seal lip 17e whose back surface is supported by the cored bar 16 is worn until the contact pressure with the slinger 22 becomes a minimum in a relatively short period of time, and thereafter the light contact state in which the rotational torque is stably reduced. To maintain. Further, since the auxiliary seal lip 17e supported by the metal core 16 is stable in shape and position, the influence due to the instability of the auxiliary seal lip 17e does not affect the main seal lip 17b.

  Therefore, according to the rolling bearing 10 of the present embodiment, the sealing device 15 includes the annular cored bar 16 and the annular elastic member 17 fixed to the cored bar 16. A main seal lip 17b projecting inward in the axial direction from the inner peripheral edge thereof and slidably in contact with a seal groove 12b provided at an end of the inner ring 12, provided radially outward from the main seal lip 17b, and the inner ring 12 Since the auxiliary seal lip 17e that can slide in contact with the side surface of the slinger 22 disposed coaxially with water, muddy water, dust and the like are difficult to reach the main seal lip, and have large waterproof and dustproof properties. Accordingly, it is possible to provide an inexpensive rolling bearing that can be used in an adverse environment where water, muddy water, dust, and the like are scattered around like an alternator.

  Further, according to the rolling bearing 10 of the present embodiment, the auxiliary seal lip 17e is disposed on the axially outer side of the cored bar 16, so that the attitude of the auxiliary seal lip 17e is increased by the cored bar 16 having high mechanical strength. The movement of the auxiliary seal lip due to contact is transmitted to the main seal lip and does not adversely affect the sealing performance of the main seal lip, so that a stable sealing performance is always provided. Further, the auxiliary seal lip is arranged on the outer side in the axial direction of the metal core, so that the auxiliary seal lip is lightly connected to the annular member when the auxiliary seal lip is in strong contact with the annular member at the initial stage of installation of the rolling bearing. Since it wears until it comes into a contact state, the contact of the auxiliary seal lip has little influence on the main seal lip thereafter, and the increase in torque due to the increase of the contact seal lip can be reduced.

  Furthermore, according to the rolling bearing 10 of the present embodiment, the elastic member 17 includes the sub seal lip 17c formed radially outward from the main seal lip 17b and protruding inward in the axial direction, and the sub seal lip 17c in the radial direction. A grease lip 17d that is formed outward and protrudes inward in the axial direction is further provided, so that a labyrinth seal is formed between the auxiliary seal lip 17c, the grease lip 17d, and the seal groove 12b of the inner ring 12, and foreign matter is mainly used. Even if it enters beyond the sliding contact portion of the seal lip 17b, it is prevented from entering the inside of the rolling bearing 10. Further, leakage of grease filled in the internal space of the rolling bearing 10 can be prevented.

  In addition, this invention is not limited to embodiment mentioned above, A deformation | transformation, improvement, etc. are possible suitably.

It is a principal part longitudinal cross-sectional view of the rolling bearing which is one Embodiment of this invention. FIG. 2 is an enlarged view of a portion surrounded by a circle II in FIG. 1. It is a principal part longitudinal cross-sectional view of the conventional rolling bearing. It is a principal part longitudinal cross-sectional view of another conventional rolling bearing.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Rolling bearing 11 Outer ring 11a Outer ring raceway surface 12 Inner ring 12a Inner ring raceway surface 12b Seal groove 13 Ball (rolling element)
DESCRIPTION OF SYMBOLS 15 Sealing device 16 Core metal 17 Elastic member 17a Outer peripheral edge part 17b Main seal lip 17c Sub seal lip 17d Grease lip 17e Auxiliary seal lip 22 Slinger (annular member)

Claims (4)

An outer ring having an outer ring raceway surface formed on an inner peripheral surface, an inner ring having an outer ring raceway surface formed on an outer peripheral surface, and a plurality of rolling elements disposed between the outer ring raceway surface and the inner ring raceway surface so as to be capable of rolling. A rolling bearing comprising: a moving body; and a sealing device having an outer peripheral edge portion fixed to an axial end portion of the outer ring and sealing between the outer ring and the inner ring,
The sealing device includes an annular cored bar and an annular elastic member fixed to the cored bar,
The elastic member protrudes inward in the axial direction from an inner peripheral edge thereof, and is provided in a radially outward direction from the main seal lip, and is in slidable contact with a seal groove provided at an end of the inner ring, and A rolling bearing comprising: an auxiliary seal lip slidably contactable with a side surface of an annular member disposed coaxially with the inner ring.   The rolling bearing according to claim 1, wherein the auxiliary seal lip is disposed outward in the axial direction of the cored bar.   The elastic member includes a sub seal lip formed radially outward from the main seal lip and protruding inward in the axial direction, and a grease lip formed outward in the radial direction from the sub seal lip and protruding in the axial direction. The rolling bearing according to claim 1, further comprising:   The rolling bearing according to claim 1, wherein the annular member is a slinger disposed adjacent to the inner ring, and is used for an alternator.

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