JP2016090010A - Rolling bearing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rolling bearing suppressing occurrence of a flaw due to foreign matter, and excellent in a service life and productivity.SOLUTION: A rolling bearing 1 includes a pair of raceway rings 20, 30, a plurality of rolling bodies 40, 41 arranged in an annular space 18 between the pair of raceway rings 20, 30, and holders 50, 60 holding the plurality of rolling bodies 40, 41; and is lubricated with lubricant 3. The holders 50, 60 comprises resin, and has a plurality of guide projections 56, 66 arranged on a circumference on at least one of the inner peripheries and outer peripheries of the holders 50, 60, and guiding the lubricant 3 to a one-side direction of an axial direction. The guide projections 56, 66 are inclined to an axial line.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a rolling bearing, and more particularly to a rolling bearing lubricated with lubricating oil.

Rolling bearings used in automobile speed reducers and the like use lubricating oil as a lubricant for raceways where a plurality of rolling elements roll.
The lubricating oil is circulated and used inside the speed reducer or the like. For this reason, foreign matters such as wear particles of the reduction gear may be mixed in the lubricating oil and enter the inside of the rolling bearing together with the lubricating oil.

  When the foreign matter enters the raceway portion, rolling due to rolling of the rolling element causes wrinkles due to the foreign matter biting into the raceway portion, thereby reducing the bearing life. In particular, in the case of a ball bearing in which the plurality of rolling elements are balls, it is found that the wrinkles are more likely to occur than the roller bearings in which the plurality of rolling elements are rollers, and the life reduction due to the wrinkles is large. ing.

  In a reduction gear for an automobile, a rolling bearing having a plurality of rolling elements in two rows with different pitch circle diameters may be used. In a rolling bearing having a plurality of rolling elements of two rows with different pitch circle diameters, the lubricating oil flowing from the side of the row with the smaller pitch circle diameter is transferred from the row with the smaller pitch circle diameter to the row with the larger pitch circle diameter. The amount of lubricating oil guided to the side and passing through the inner space of the bearing is increased compared to a normal bearing.

When the amount of lubricating oil passing through the bearing internal space is large, a large stirring resistance is generated when the rolling element rolls, and the amount of foreign matter entering also increases.
Therefore, in order to reduce the agitation resistance of the lubricating oil and reduce the amount of the lubricating oil mixed with foreign matter passing through the inner space of the bearing, the retainer that holds the rolling elements is suppressed from flowing in the lubricating oil. There is a rolling bearing formed into a shape. (See Patent Document 1)

JP 2006-234100 A

  However, when the inflow of the lubricating oil into the bearing internal space is suppressed, the flow speed of the lubricating oil inside the rolling bearing decreases, and the movement of the foreign matter mixed in the lubricating oil becomes dull, and the inside of the bearing The foreign matter that has entered the space may remain in the track portion. When the foreign matter remains in the track portion, the occurrence of wrinkles in the track portion due to the biting of the foreign matter is greatly increased.

  The present invention provides a rolling bearing that suppresses the generation of wrinkles due to the foreign matter, prevents the foreign matter mixed in the lubricating oil from remaining in the raceway portion, and has excellent life and productivity. It is an object.

  In order to solve the above-mentioned problem, the structural feature of the invention according to claim 1 is that a plurality of rolling elements lubricated with lubricating oil and disposed in a pair of race rings and an annular space between the pair of race rings. A rolling bearing having a moving body and a cage for holding the plurality of rolling elements, wherein the lubricating oil is guided to at least one of an inner circumference and an outer circumference of the cage in one axial direction. On the other hand, it has oil guide means which inclines, the cage is made of resin, and the oil guide means is made up of a plurality of guide protrusions arranged on the circumference.

  According to the configuration of the present invention, with the rotation of the bearing, it is guided to the plurality of guide protrusions inclined with respect to the axis, and a flow toward one side of the rolling bearing is generated in the lubricating oil. By this flow, the lubricating oil in the bearing inner space is guided to the outside of the rolling bearing together with the foreign matter contained in the lubricating oil. As a result, foreign matter remaining in the track portion is reduced, and wrinkles of the track portion due to biting of the foreign matter, which are generated by rolling of the rolling elements, are suppressed, and a reduction in life due to wrinkles can be prevented. .

  Further, the cage is made of resin, and the plurality of guide protrusions can be easily formed by injection molding or the like. Further, the radial gap between the tip of the guide projection and the raceway where the guide projection faces in the radial direction is small, and most of the lubricating oil passing between the cage and the raceway is caused by the guide projection. Lubricant flow occurs. Due to the reliable flow of the lubricating oil between the cage and the raceway, the foreign matter remaining on the raceway portion is reduced, and the generation of wrinkles due to the foreign matter can be further suppressed.

  In order to solve the above-described problem, the structural feature of the invention according to claim 2 is that an end of the cage on one side in the axial direction of the guide projection and an axis on the other side in the axial direction of the adjacent guide projection are provided. An end means that it does not overlap in the circumferential direction.

  According to the configuration of the present invention, the guide protrusion that is inclined with respect to the axis can be easily formed using an injection molding die that is divided into two in the axial direction. That is, it is not necessary to use a complicated type such as a radial type and a complicated process, and the productivity of the cage is very excellent.

In order to solve the above-mentioned problem, the structural feature of the invention according to claim 3 is that the plurality of rolling elements are two rows of rolling elements having different pitch circle diameters,
The one direction in the axial direction is a direction in which the lubricating oil is guided in the axial direction from a row having a small pitch circle diameter to a row having a large pitch circle diameter.

  In rolling bearings having a plurality of rolling elements of two rows with different pitch circle diameters, in order to suppress the inflow of foreign matter into the rolling bearings and reduce the stirring resistance of the lubricating oil, A configuration that suppresses the inflow of lubricating oil as much as possible is adopted. When the inflow of lubricating oil into the rolling bearing is suppressed, the flow rate of the lubricating oil inside the rolling bearing decreases, the movement of the foreign matter mixed in the lubricating oil becomes dull, and the foreign matter becomes May remain in the track.

  According to the configuration of the present invention, the lubricating oil that has flowed into the inside of the rolling bearing from the side of the row having a small pitch circle diameter is guided to the plurality of guiding protrusions inclined with respect to the axis, A flow toward the side of the row having a large pitch circle diameter is generated, and the flow velocity is increased. By this flow, the lubricating oil in the inner space of the bearing is guided to the outside of the rolling bearing together with the foreign matter remaining in the raceway portion. The foreign matter remaining in the raceway portion is guided to the outside of the rolling bearing, so that wrinkles due to the foreign matter biting in the raceway portion caused by rolling of the rolling elements are suppressed, and the lifespan is shortened by wrinkles. Can be prevented.

  In order to solve the above problem, a structural feature of the invention according to claim 4 is that the plurality of rolling elements are a plurality of balls.

  When the rolling element is a ball, the rolling contact pressure is high. Compared with the case where the rolling element is a roller, wrinkles due to foreign matter are more likely to occur, and the effect of wrinkles on the life is greater. For this reason, by applying the configuration of the present invention to the rolling bearing in which the rolling element is a ball, it is possible to further suppress the decrease in the life due to the rod.

  As described above, according to the present invention, it is possible to provide a rolling bearing that suppresses generation of wrinkles due to foreign matters, has a long life, and has excellent productivity.

It is sectional drawing of the rolling bearing of one Embodiment of this invention. It is a perspective view of the holder | retainer of the rolling bearing of one Embodiment of this invention. It is explanatory drawing explaining the use condition of the rolling bearing of one Embodiment of this invention. It is sectional drawing explaining the shaping | molding die of the cage of the rolling bearing of one Embodiment of this invention. It is an expanded view explaining the shaping | molding die of the cage of the rolling bearing of one Embodiment of this invention.

  A rolling bearing according to an embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a cross-sectional view of a rolling bearing 1 according to an embodiment of the present invention.
FIG. 2 is a perspective view of the main part of the rolling bearing 1 according to the embodiment of the present invention, is an enlarged explanatory view of the cage, and schematically shows the main part. The arrow indicates the direction of rotation of the cage.

  1 and 2, a rolling bearing 1 according to an embodiment of the present invention includes an outer ring 20 in which two rows of outer ring raceways 21 and 22 having different diameters are formed on the inner circumference, and two rows of inner rings having different diameters on the outer circumference. A plurality of rolling elements arranged to be freely rollable in the bearing inner space 18, which is an annular space between the outer ring raceway 21 and the inner ring raceway 31, and a pair of raceways with the inner race 30 in which the raceways 31 and 32 are formed. Ball 40, a retainer 50 that holds the ball 40, a plurality of balls 41 as rolling elements that are disposed between the outer ring raceway 22 and the inner ring raceway 32, and a holder that holds the plurality of balls 41. Instrument 60.

  The outer ring 20 is a ring made of a steel material such as bearing steel, and outer ring raceways 21 and 22 having an arc-shaped cross section are formed on both sides of the inner circumference with an outer ring intermediate shoulder 23 at the center in the axial direction. The diameter of the outer ring raceway 21 is larger than the diameter of the outer ring raceway 22. An outer ring counter bore 24 is formed in the axial direction from the end of the outer ring raceway 21 opposite to the outer ring intermediate shoulder 23. An outer ring shoulder 25 is formed in the axial direction from the end of the outer ring raceway 22 opposite to the outer ring intermediate shoulder 23. Further, the outer diameter of the outer ring shoulder 25 is determined in consideration of the distance from the inner periphery of the cage 60 in order to suppress the inflow of the lubricating oil 3 into the bearing internal space 18.

The inner ring 30 is an annular body made of a steel material such as bearing steel, and two rows of inner ring raceways 31 and 32 having a circular arc shape are formed on the outer periphery in the center in the axial direction. The diameter of the inner ring raceway 31 is larger than the diameter of the inner ring raceway 32.
The plurality of balls 40 and 41 are steel balls for bearing made of a steel material such as bearing steel. The plurality of balls 40 and 41 are arranged in two rows having different pitch circle diameters, and the pitch circle diameter of the plurality of balls 40 is larger than the pitch circle diameter of the plurality of balls 41.

  The cages 50 and 60 are made of a resin such as reinforced polyamide and are formed by a mold. The cage 60 differs from the cage 50 only in size, and the configuration, function, action, and effect are the same as the cage 50. Therefore, the cage 50 will be described below, and the description of the cage 60 will be omitted.

  The cage 50 has two annular portions 52 and 53 at both axial ends, and a pillar portion 54 that connects the annular portions 52 and 53 in the axial direction, and the pillar portion 54 has both annular portions 52. , 53 together with the side surface of the rolling element 40, 53 constitutes a pocket 51 for holding the rolling element 40. The inner diameter of the annular part 52 is formed larger than the outer diameter of the annular part 53.

  The outer circumference of the annular portion 52 is a cylindrical cage outer circumference 55 parallel to the axis. A plurality of guide protrusions 56 are arranged on the circumference of the cage 55 equally on the circumference. The heights of the respective guide protrusions 56 are equal, and the front end portion 59 of the guide protrusion 56 faces the outer ring counter bore 24 of the outer ring 20, and the diameter of the circumscribed circle of each front end portion 59 is slightly smaller than the diameter of the outer ring counter bore 24. It is formed small.

  Further, each guide protrusion 56 is formed so that the opposite side to the axial pocket 51 is shifted in the rotational direction of the cage (the arrow direction in FIG. 2) with respect to the axial pocket 51 side. That is, the axial direction pocket 51 side is inclined with respect to the axial direction in the rotation direction of the cage (the arrow direction in FIG. 2). Furthermore, the rotation of the cage of the guide protrusion 56 adjacent to the one side in the axial direction, that is, the end of the pocket 51 side of the side surface 57 in the rotation direction of the cage 50 of each guide projection 56 and the rotation direction of the cage, respectively. The other side of the side surface 58 in the opposite direction to the direction, that is, the end opposite to the pocket 51 is formed in a positional relationship that does not overlap in the circumferential direction when viewed in the axial direction.

Hereinafter, the operation and effect of the rolling bearing 1 according to the embodiment of the present invention will be described.
FIG. 3 is an explanatory diagram for explaining a usage state of the rolling bearing 1 according to the embodiment of the present invention.

As shown in FIG. 3, the rolling bearing 1 is incorporated in a final reduction gear 10 of an automobile, and supports the small gear shaft 12 together with the rolling bearing 2 so as to be rotatable.
The final reduction gear 10 is filled with lubricating oil 3 for lubrication of the small gear 13 and the large gear 14 and lubrication of the rolling bearing 1 and the rolling bearing 2. When the vehicle moves forward, the lubricating oil 3 passes from the oil reservoir 17 through the inflow path 15, the bearing intermediate portion 16, and the bearing internal space 18 of the rolling bearing 1 by the rotation of the large gear 14 and circulates in the oil reservoir 17.

  Further, in the rolling bearing 1 according to the embodiment of the present invention, the radial gap between the distal end portion 59 of the guide projection 56 and the outer ring counter bore 24 of the outer ring 20 is small, and the outer circumference of the cage 50 and the outer ring counter bore 24 are reduced. Most of the lubricating oil 3 passing between them passes between the adjacent guide projections 56, that is, between the side surfaces 57 and 58.

  As the usage time elapses, the circulating lubricating oil 3 is mixed with foreign matter such as wear powder of the small gear 13 and the large gear 14, and a part of the lubricating oil 3 mixed with the foreign matter passes through the bearing internal space 18. Foreign matter mixed in the lubricating oil 3 passing through the bearing internal space 18 may remain on the outer ring raceway 21. When the ball 40 rolls on the outer ring raceway 21 where foreign matter remains, wrinkles are generated on the surface of the ball 40, the outer ring raceway 21, and the inner ring raceway 31.

Here, due to the rotation of the inner ring 30 of the rolling bearing 1 when the vehicle moves forward, the cage 50 rotates in the direction of the arrow in FIG.
In the rolling bearing 1 of one embodiment of the present invention. The plurality of guide protrusions 56 are formed such that the pocket 51 side is inclined in the axial direction with respect to the axial direction in the rotation direction of the cage (arrow direction in FIG. 2).

  Therefore, when the cage 50 rotates in the direction of the arrow in FIG. 2, the lubricating oil 3 between the adjacent guide projections 56, that is, between the side surface 57 and the side surface 58, has a plurality of guide projection side surfaces 58 inclined with respect to the axis. The direction of the flow is changed by this, and a flow is generated in the lubricating oil 3 in one axial direction, that is, in the direction of the oil sump 17 (the white arrow in FIG. 2). Also in the cage 60, as in the cage 50, a flow is generated in one direction, that is, in the direction of the oil sump 17 (the white arrow in FIG. 2).

  By this flow, the flow velocity of the lubricating oil 3 passing through the bearing internal space 18 of the rolling bearing 1 is increased, and the lubricating oil 3 has a large pitch circle diameter from a row having a small pitch circle diameter together with foreign matters remaining on the outer ring raceway 21. It is guided in the direction of the row, passes between the outer periphery of the cage 50 and the outer ring counter bore 24 and flows out in the direction of the oil sump 17 (the white arrow in FIG. 2). The same action as described above also occurs between the retainer 60 and the outer ring intermediate shoulder 23, and foreign matter remaining on the outer ring raceway 22 also flows out in the direction of the oil sump 17 (the white arrow in FIG. 2).

For this reason, the foreign matters remaining on the outer ring raceways 21 and 22 are reduced, and the occurrence of wrinkles on the outer ring raceways 21 and 22 and the inner ring raceways 31 and 32 due to the inclusion of the foreign matters is suppressed.
In particular, the rolling bearing 1 is a ball bearing in which a plurality of rolling elements are balls 40 and 41, the surface pressure of the rolling contact portion is high, and wrinkles are likely to occur. For this reason, the effect of preventing wrinkles due to the reduction of foreign matters is greater than that of a roller bearing in which a plurality of rolling elements are rollers.

  As described above, in the rolling bearing 1 according to the embodiment of the present invention, the wrinkles of the outer ring raceways 21 and 22 and the inner ring raceways 31 and 32 caused by the rolling of the balls 40 and 41 are suppressed, and the life reduction due to the wrinkles is prevented. be able to.

FIG. 4 is a cross-sectional view illustrating a forming die 70 of the cage 50 of the rolling bearing according to the embodiment of the present invention. The mold 70 includes an upper mold 71 and a lower mold 72.
FIG. 5 is a developed view for explaining a forming die 70 of the cage of the rolling bearing 1 according to the embodiment of the present invention, and shows a cross section taken along the line AA of FIG.

In the cage 50 of the rolling bearing 1 according to the embodiment of the present invention, the inner diameter dimension of the annular portion 52 is formed larger than the outer diameter dimension of the annular portion 53, and the upper mold 71 and the lower mold 72 are arranged in an axis line. Separation is possible in the direction.
Here, in the rolling bearing 1 according to the embodiment of the present invention, one end of the guide projection 55 adjacent to the axial pocket 51 side of the side surface 58 on the rotational direction side of the cage 50 is adjacent to the rotational direction of the cage. The guide protrusion 55 is formed in a positional relationship so as not to overlap in the circumferential direction with the axial pocket 51 on the side surface 57 opposite to the rotation direction of the cage 50 and the end on the opposite side. That is, there is a circumferential gap Δ between adjacent guide protrusions 55.

In the mold 70 of the cage 50, as shown in FIG. 5, there is a circumferential gap Δ between the guide projection forming surface 73 of the upper mold 71 and the guide projection forming surface 74 of the lower mold 72. By arranging slide surfaces 75 and 76 of the upper mold 71 and the lower mold 72 parallel to the axis in the middle of the gap Δ,
After molding, the upper mold 71 and the lower mold 72 can be easily separated in the axial direction.

  As described above, the rolling bearing 1 according to an embodiment of the present invention suppresses generation of wrinkles due to foreign matters, has a long life, and is excellent in productivity.

  In the above-described embodiment, the rotation direction of the cage of the guide projection 56 adjacent to the end portion on the axial pocket 51 side of the side surface 57 in the rotation direction of the cage 50 of one guide projection 56 and the rotation direction of the cage. In the present invention, the axial pocket 51 of the side surface 58 on the opposite side and the end on the opposite side are formed so as not to overlap each other in the circumferential direction. An end of the side surface 57 of the side surface 57 on the side of the axial pocket 51 and an end of the guide projection 56 adjacent to the direction of rotation of the cage opposite to the axial pocket 51 of the side surface 58 of the side surface 58 opposite to the direction of rotation of the cage. May be formed in a positional relationship overlapping in the circumferential direction.

  In the above-described embodiment, the rolling bearing 1 is a ball bearing having a plurality of balls having two rows of different pitch circle diameters. In the present invention, the ball bearing having a plurality of balls having two rows of equal pitch circle diameters, Other types of rolling bearings such as single row ball bearings may also be used.

  In the above-described embodiment, the plurality of guide protrusions 56 are formed on the outer periphery of the retainer 50. However, in the present invention, the plurality of guide protrusions 56 may be formed on the inner periphery of the retainer 50.

  In the above-described embodiment, the rolling bearing 1 is a ball bearing in which a plurality of rolling elements are balls 40 and 41. However, in the present invention, other types such as a tapered roller bearing in which the plurality of rolling elements are tapered rollers are used. It may be a rolling bearing.

  The present invention is not limited to such embodiments, and can naturally be implemented in various modes without departing from the gist of the present invention.

1, 2 ... Rolling bearings 3 ... Lubricating oil 11 ... Bearing internal space (annular space)
20 ... Outer ring (Raceway)
21, 22 ... Outer ring raceway 30 ... Inner ring (Raceway ring)
31, 32 ... Inner ring raceway 40, 41 ... Ball (rolling element)
50, 60 ... Cage 56, 66 ... Guide protrusion

Claims (4)

A rolling bearing having a pair of bearing rings, a plurality of rolling elements disposed in an annular space between the pair of bearing rings, and a cage for holding the plurality of rolling elements, and lubricated with lubricating oil Because
The cage is made of resin,
At least one of the inner periphery and the outer periphery of the cage has a plurality of guides arranged on the circumference to guide the lubricating oil in one axial direction;
The rolling bearing, wherein the plurality of guide protrusions are inclined with respect to an axis.   The rolling bearing according to claim 1, wherein an end portion on one side in the axial direction of the guide protrusion and an end portion on the other side in the axial direction of the adjacent guide protrusion do not overlap in the circumferential direction. The plurality of rolling elements are a plurality of rolling elements in two rows having different pitch circle diameters.
The one axial direction is a direction in which the lubricating oil is guided in the axial direction from a row having a small pitch circle diameter to a row having a large pitch circle diameter.
The rolling bearing according to claim 1, wherein the rolling bearing is provided.   4. The rolling bearing according to claim 1, wherein the plurality of rolling elements are a plurality of balls. 5.

Images