JP5239540B2 - Rolling bearings and bearing units - Google Patents

Description

  The present invention relates to a rolling bearing and a bearing unit that are lubricated with a shaft oil supply.

  In general, when a rolling bearing rotates, the air around the bearing is rotated along with the rotation of the bearing to generate an air curtain. When rolling bearings are rotated at a high speed due to the recent demand for high-speed rotation, the layer of air curtain generated also increases, which makes it difficult to introduce lubricating oil into the bearing and causes, for example, bearing seizure due to lack of lubricating oil. There was a risk.

  For example, the rolling bearing unit 100 as shown in FIG. 9 is inexpensive and is widely used as a bearing unit. However, during high-speed rotation, the lubricating oil supplied from the lubricating oil supply port 101 cannot penetrate the air curtain. There was a risk that the lubricating oil would not run through the bearing, resulting in a shortage of lubricating oil.

In order to cope with this problem, in Patent Document 1, a spacer 202 is provided between inner rings 201 and 201 arranged side by side as shown in FIG. A rolling bearing 200 is disclosed in which the lubricating oil can penetrate the air curtain by increasing the inertial force.
JP 2008-19948 A

  However, with this structure, there is a problem that it is necessary to provide a spacer, which increases the cost, and it is necessary to secure a space for providing the spacer, and in some cases, it cannot be installed. It was.

  The present invention has been made in order to eliminate such inconveniences, and the object of the present invention is to provide a rolling bearing and a rolling bearing capable of supplying lubricating oil inside the bearing even at high speed rotation while reducing cost and saving space. It is to provide a bearing unit.

The above object of the present invention can be achieved by the following constitution.
(1) An inner ring, an outer ring, and a plurality of rolling elements disposed between the inner ring and the outer ring so as to be freely rollable in the circumferential direction, a lubricating oil supply port is formed, and the inner ring is externally fitted In rolling bearings where lubricating oil can be supplied from the shaft,
A lubricating oil intake portion that extends radially inward from the inner peripheral surface of the outer ring and converts the flow of the lubricating oil discharged from the lubricating oil supply port to the rolling bearing side in the vicinity of the position facing the lubricating oil supply port Is provided,
The lubricating oil intake portion includes a tapered portion that gradually increases in diameter toward the rolling bearing side, an inner peripheral surface that extends substantially parallel to the shaft and is positioned on the inner diameter side of the tapered portion, and the tapered portion. A vertical surface that connects the inner peripheral surface in the radial direction,
The distance between the shaft and the inner circumferential surface, rather short than the distance between the vertical surface and the inner ring end face,
The inner peripheral surface is opposed to the shaft through a gap,
The rolling bearing according to claim 1, wherein the lubricating oil flowing into the bearing is discharged to a side opposite to the lubricating oil intake portion .
(2) The rolling bearing according to (1), wherein the lubricating oil intake portion is formed in the outer ring.
(3) The rolling bearing according to (1 ) ,
In a bearing unit comprising a housing in which the outer ring is fitted,
The bearing unit, wherein the lubricating oil intake portion is formed in the housing.
(4) The rolling bearing according to (1 ) ,
A housing in which the outer ring is fitted;
In a bearing unit comprising a ring member between the housing and the rolling bearing in the axial direction,
The bearing unit, wherein the lubricating oil intake portion is formed in the ring member.

  According to the rolling bearing and the rolling bearing unit of the present invention, the flow of the lubricating oil that extends radially inward from the inner peripheral surface of the outer ring and is discharged from the lubricating oil supply port in the vicinity of the position facing the lubricating oil supply port. Since there is a lubricating oil intake section that converts to the rolling bearing side, the flow of lubricating oil discharged from the lubrication supply port is converted to the bearing side, and even during high-speed rotation, it passes through the air curtain and is required inside the bearing. Can be supplied.

  In addition, by forming the lubricating oil intake part in the outer ring or in the housing in which the bearing is inserted, the components of the rolling bearing or the bearing unit can be used as the lubricating oil intake part, so that a separate spacer can be used. There is no need to provide it, and it is possible to achieve low cost and space saving.

  Hereinafter, embodiments of a rolling bearing and a rolling bearing unit according to the present invention will be described in detail with reference to the drawings.

<First Embodiment>
As shown in FIG. 1, the rolling bearing unit 10 of the present embodiment includes an inner ring 21, an outer ring 22, and a plurality of rolling elements that are disposed between the inner ring 21 and the outer ring 22 so as to be freely rotatable in the circumferential direction. A deep groove ball bearing 20 having a certain ball 23, a housing 30 in which the outer ring 22 is fitted, and a rotary shaft 40 in which the inner ring 23 is fitted are provided.

  The inner ring 21 has an inner ring raceway groove 21a formed in the outer peripheral surface thereof, and a rotary shaft 40 is fitted in the inner peripheral surface thereof.

  The outer ring 22 has an outer ring raceway groove 22a formed in an inner peripheral surface thereof, and a housing 30 is fitted on the outer peripheral surface thereof.

  The plurality of balls 23 are rotatably arranged between the inner ring raceway groove 21 a of the inner ring 21 and the outer ring raceway groove 22 a of the outer ring 22, and are held at substantially equal intervals in the circumferential direction by the cage 24. And the outer ring 22 can freely rotate relative to each other.

  The retainer 24 is a so-called crown-shaped retainer. The retainer 24 is provided with an annular portion 24a on the lubricating oil supply port 42 side described later, and a pocket for retaining the ball 23 is open on the opposite side.

  The rotating shaft 40 includes a step portion 41 on one axial side (right side in the drawing) for positioning on the one axial side of the inner ring 21, and an outer peripheral surface on the other axial side with the deep groove ball bearing 20 interposed therebetween. A lubricating oil supply passage 43 is formed in which a lubricating oil supply port 42 is opened.

  An annular convex portion 31 that restricts the movement of the deep groove ball bearing 20 to the other side in the axial direction (left side in the drawing) is extended on the housing 30 inward in the radial direction.

  Further, the convex portion 31 is provided in the vicinity of a position facing the lubricating oil supply port 42 formed in the rotating shaft 40, and the inner peripheral surface of the convex portion 31 is radially inward from the inner peripheral surface of the outer ring 22. Extending to the vicinity of the outer peripheral surface of the inner ring 21.

  Further, a tapered surface 32 (tapered portion) that gradually increases in diameter toward the deep groove ball bearing 20 side is formed on the inner peripheral surface of the convex portion 31, and the tapered surface 32 is inclined by approximately 45 ° with respect to the radial direction. Yes. The outermost diameter portion 32 a of the tapered surface 32 is located slightly outside the pitch circle diameter PCD of the ball 23, and the outermost diameter portion 32 a of the tapered surface 32 is the outer peripheral surface of the inner ring 21 and the inner periphery of the outer ring 22. It is comprised so that it may open to the bearing space formed of the surface. Thereby, in this embodiment, the taper surface 32 formed in the internal peripheral surface of the convex part 31 and the convex part 31 converts the flow of the lubricating oil discharged | emitted from the lubricating oil supply port 42 to the deep groove ball bearing 20 side. The lubricating oil take-in part 50 is configured.

  Further, the axial length Lt of the tapered surface 32 is longer than the axial length Lo of the lubricating oil supply port 42.

  In the bearing unit 10 configured in this way, the lubricating oil is discharged from the lubricating oil supply port 42 to the outside of the rotating shaft 40 through the lubricating oil supply passage 43 formed in the rotating shaft 40 perpendicular to the axial direction. The At this time, the lubricating oil flows radially outward due to the centrifugal force of the rotating shaft 40, and the flow of the lubricating oil is converted from the radial direction to the axial direction by the tapered surface 32 formed on the convex portion 31 of the housing 30. Lubricating oil that has flowed into the bearing is agitated by the cage 24 and balls 23 as the deep groove ball bearing 20 rotates, and is discharged from the end of the deep groove ball bearing 20 on the side opposite to the inflow side.

  According to the bearing unit 10 of the present embodiment, the convex portion 31 and the tapered surface 32 formed on the inner peripheral surface of the convex portion 31 function as the lubricating oil intake portion 50, and lubrication discharged from the lubricating oil supply port 42. Since the oil flow is converted to the deep groove ball bearing 20 side, the amount of lubricating oil that does not flow into the deep groove ball bearing 20 but flows to the opposite side to the deep groove ball bearing 20 side can be reduced, and the lubricating oil to the deep groove ball bearing 20 side can be reduced. The amount can be increased. Thereby, even at the time of high speed rotation, the lubricating oil can penetrate the air curtain and supply the necessary lubricating oil into the bearing.

  Moreover, since the convex part 31 and the taper surface 32 can be provided in the housing 30, the increase in a number of parts can be suppressed and, thereby, cost reduction can be aimed at. Furthermore, a general-purpose bearing can be used. In addition, the convex part 31 should just protrude toward the rotating shaft 40 from the internal peripheral surface of the housing 30, and may protrude so that a step part may be formed, or may protrude in the shape of a flange.

  Further, since the axial length Lt of the tapered surface 32 is longer than the axial length Lo of the lubricating oil supply port 42, even if the lubricating oil discharged from the lubricating oil supply port 42 has diffused. Since the lubricating oil is guided into the bearing along the tapered surface 32, more lubricating oil can be supplied to the deep groove ball bearing 20 side.

  In the present embodiment, the inclination of the tapered surface 32 is approximately 45 ° with respect to the rotation shaft 40, but is not particularly limited to this, and can be adjusted to an arbitrary angle. Further, instead of the tapered surface 32, an arc portion having an arc-shaped cross section may be formed.

  Further, in the present embodiment, the outermost diameter portion 32a of the tapered surface 32 is set to be positioned slightly on the outer diameter side from the pitch circle diameter PCD of the balls 23. The effect of the present invention can be achieved if it is set to be on the larger diameter side and on the smaller diameter side than the inner peripheral surface of the outer ring 22.

Second Embodiment
FIG. 2 is a longitudinal sectional view of an essential part of a bearing unit according to the second embodiment of the present invention. In the figure, the same components as those in the first embodiment are denoted by the same reference numerals and description thereof is omitted.
In the bearing unit 10 </ b> A of the present embodiment, a stepped portion 62 is provided instead of the tapered surface 32 as shown in FIG. 2.

  The step portion 62 is opposed to the lubricating oil supply port 42, extends substantially parallel to the rotation shaft 40, and is positioned in the vicinity of the pitch circle diameter PCD of the ball, and the radial direction from the first inner peripheral surface 63. A second inner peripheral surface 64 that is inside and extends substantially parallel to the rotation shaft 40 and is located in the vicinity of the outer peripheral surface of the inner ring 21, and a first inner peripheral surface 63 and a second inner peripheral surface 64 are connected to each other in the radial direction. In this embodiment, the stepped portion 31 and the stepped portion 62 formed at the tip of the protruding portion 31 flow the lubricating oil discharged from the lubricating oil supply port 42 in the deep groove ball bearing 20. The lubricating oil intake part 50 to be converted to the side is configured.

  As a result, like the tapered surface 32 of the first embodiment, the lubricating oil discharged from the lubricating oil supply port 42 by the first inner peripheral surface 63 and the vertical wall 64 constituting the stepped portion 62 is removed from the radial direction. The flow of the lubricating oil is converted in the direction, and the necessary lubricating oil can be supplied into the bearing through the air curtain even at high speed rotation.

  FIG. 3 is a cross-sectional view of a main part showing a modification of the second embodiment of the present invention. As shown in FIG. 3, the bearing unit 10 </ b> B of the present modification is configured such that the first inner peripheral surface 63 of the second embodiment is positioned in the vicinity of the inner peripheral surface of the outer ring 22.

  Thereby, the radial direction length of the vertical surface 65 becomes long, and the space formed by the first inner peripheral surface 63 and the vertical surface 65 can be secured. Thereby, the flow of the lubricating oil to the opposite side to the deep groove ball bearing 20 is suppressed by the vertical wall 63, and the flow of the lubricating oil is converted from the radial direction to the axial direction by the step portion 62 formed in the housing 30. .

<Third Embodiment>
FIG. 4 is a longitudinal sectional view of an essential part of a bearing unit according to a third embodiment of the present invention. In the figure, the same components as those of the second embodiment are denoted by the same reference numerals and description thereof is omitted.
In the bearing unit 10C of the present embodiment, as shown in FIG. 4, the first inner peripheral surface 63 in the second embodiment is replaced with a tapered surface that gradually increases in diameter toward the deep groove ball bearing 20 side, The peripheral surface 64 is extended to the vicinity of the outer peripheral surface of the rotating shaft 40. In the present embodiment, the convex portion 31 and the stepped portion 62 formed at the tip of the convex portion 31 are lubricated from the lubricating oil supply port 42. The lubricating oil intake part 50 which converts the flow of oil to the deep groove ball bearing 20 side is configured.

  Thereby, the flow of the lubricating oil is converted from the radial direction to the axial direction by the tapered first inner peripheral surface 63a formed on the convex portion 31 of the housing 30. Further, the radial length of the vertical surface 65 is increased, and a space formed by the first inner peripheral surface 63a and the vertical surface 65 can be secured. Thereby, the flow of the lubricating oil to the opposite side to the deep groove ball bearing 20 is suppressed by the vertical wall 65, and the lubricating oil can pass through the air curtain and supply the necessary lubricating oil into the bearing even during high-speed rotation. it can.

  Further, since the second inner peripheral surface 64a extends to the vicinity of the outer peripheral surface of the rotating shaft 40, the escape route of the lubricating oil bounced off by the first inner peripheral surface 63a can be reduced, and more lubricating oil can be stored. The deep groove ball bearing 20 can be penetrated.

<Fourth embodiment>
FIG. 5 is a longitudinal sectional view of an essential part of a bearing unit according to a fourth embodiment of the present invention. In the figure, the same components as those in the first embodiment are denoted by the same reference numerals and description thereof is omitted.
In the bearing unit 10D of the present embodiment, as shown in FIG. 5, a ring member is provided between the convex portion 31 of the housing 30 and the outer ring 22 of the deep groove ball bearing 20 and in the vicinity of the position facing the lubrication supply port 42. 70 is provided, and the inner peripheral surface of the ring member 70 extends radially inward from the inner peripheral surface of the outer ring 22 to the vicinity of the outer peripheral surface of the inner ring 21.

  Further, a tapered surface 72 (tapered portion) that gradually increases in diameter toward the deep groove ball bearing 20 side is formed on the inner peripheral surface of the ring member 70, and the tapered surface 72 is inclined by approximately 45 ° with respect to the rotating shaft 40. ing. In the present embodiment, the ring member 70 and the tapered surface 72 formed on the inner circumferential surface of the ring member 70 convert the lubricating oil flow discharged from the lubricating oil supply port 42 to the deep groove ball bearing side. The insertion part 50 is comprised. The configuration of the tapered surface 72 is the same as that of the tapered surface 32 of the first embodiment.

  As a result, like the tapered surface 32 of the first embodiment, the flow of the lubricating oil is converted from the radial direction to the axial direction by the tapered surface 72 formed on the inner peripheral surface of the ring member 70. As a result, the necessary lubricating oil can be supplied into the bearing through the air curtain even during high-speed rotation.

  FIG. 6 is a partial perspective view of a ring member showing a modification of the fourth embodiment of the present invention. In this modification, as shown in FIG. 6, a screw portion 74 in which a female screw is formed is formed on the inner peripheral surface 73 of the ring member 70 of the fourth embodiment.

  As the lubricating oil flows along the thread groove, the lubricating oil flows toward the deep groove ball bearing 20. As a result, the threaded portion 74 together with the tapered surface 72 can generate a flow of lubricating oil toward the deep groove ball bearing side, and supply the necessary lubricating oil into the bearing through the air curtain even during high-speed rotation. be able to. The angle of the lubricating oil supply path 43 may be adjusted so that the lubricating oil flows along the thread groove.

<Fifth Embodiment>
FIG. 7 is a longitudinal sectional view of an essential part of a bearing unit according to a fifth embodiment of the present invention. In the figure, the same components as those in the first embodiment are denoted by the same reference numerals and description thereof is omitted.
In the bearing unit 10E of the present embodiment, as shown in FIG. 7, a flange portion 80 extending in the radial direction is integrally formed at the end portion on the one axial side of the outer ring 22, and the inner peripheral surface of the flange portion 80 is The outer ring 22 extends radially inward from the inner circumferential surface of the outer ring 22 to the vicinity of the outer circumferential surface of the inner ring 21.

  Further, a tapered surface 82 (tapered portion) that gradually increases in diameter toward the deep groove ball bearing 20 side is formed on the inner peripheral surface of the flange portion 80, and the tapered surface 82 is inclined by approximately 45 ° with respect to the rotating shaft 40. ing. In this embodiment, the flange portion 80 and the tapered surface 82 formed on the inner peripheral surface of the flange portion 80 convert the lubricating oil flow discharged from the lubricating oil supply port 42 to the deep groove ball bearing side. The insertion part 50 is comprised. The configuration of the tapered surface 82 is the same as the tapered surface 32 of the first embodiment.

  As a result, like the tapered surface 32 of the first embodiment, the flow of the lubricating oil is converted from the radial direction to the axial direction by the tapered surface 82 formed on the inner peripheral surface of the flange portion 80 of the outer ring 22. As a result, the necessary lubricating oil can be supplied into the bearing through the air curtain even during high-speed rotation.

  Further, in the present embodiment, since the lubricating oil intake portion 50 is provided in the deep groove ball bearing 20 itself, it is not necessary to perform special processing on the housing 30 and the number of parts can be reduced.

[Penetration oil amount comparison test]
Next, examples of the bearing unit according to the present invention will be described.
Using the bearing units shown in FIGS. 8 (a) and 8 (b), the ratio of the amount of penetrating oil discharged through the bearing to the amount of oil supplied from the lubricating oil supply port is obtained under the following conditions. It was.

  The bearing unit shown in FIG. 8 (a) used as an example is an example of the bearing unit 10 of the fourth embodiment shown in FIG. 5, and the bearing unit shown in FIG. 8 (b) used as a comparative example is a ring. 8A differs from the bearing unit shown in FIG. 8A in that the inner diameter of the member is substantially flush with the inner peripheral surface of the outer ring. However, the same test is used except for the inner diameter of the ring member. The test was conducted under conditions.

<specification>
Bearing name number: Single row deep groove ball bearing 6909
Ball pitch circle diameter: 56.5mm
Cage: Spherical pocket crown type cage Cage material: Polyamide 46 (filled with 25% carbon fiber)

<Test conditions>
Lubrication method: VG24 mineral oil forced lubrication Oil quantity: 0.5 L / min
Lubrication temperature: 40 ° C
Rotation speed: 10000rpm
Load: 20kgf

  Table 1 shows the test results of the penetration oil amount comparison test. From the result of this comparative test, it can be seen that more than twice as much lubricating oil penetrates the bearing in the bearing unit of this example compared to the comparative example.

  From the above results, in the vicinity of the position facing the lubricating oil supply port, the lubricating oil intake that extends radially inward from the inner peripheral surface of the outer ring and discharges the lubricating oil flow discharged from the lubricating oil supply port to the rolling bearing side. It can be seen that more lubricating oil passes through the bearing by providing the insertion portion. As a result, the necessary lubricating oil can be supplied into the bearing through the air curtain even during high-speed rotation.

  In addition, this invention is not limited to embodiment mentioned above, A deformation | transformation, improvement, etc. are possible suitably. In addition, the material, shape, dimension, numerical value, form, number, arrangement location, and the like of each component in the above-described embodiment are arbitrary and are not limited as long as the present invention can be achieved.

  For example, although the crown type cage is illustrated as the cage of the present embodiment, the present invention is not limited to this, and a known cage shape and cage material can be used.

  Moreover, although the deep groove ball bearing was illustrated as a bearing of this embodiment, not only this but a well-known rolling bearing, for example, an angular ball bearing, a roller bearing, etc. can be used.

It is principal part sectional drawing of the bearing unit of 1st Embodiment which concerns on this invention. It is principal part sectional drawing of the bearing unit of 2nd Embodiment which concerns on this invention. It is principal part sectional drawing of the bearing unit of the modification of 2nd Embodiment which concerns on this invention. It is principal part sectional drawing of the bearing unit of 3rd Embodiment which concerns on this invention. It is principal part sectional drawing of the bearing unit of 4th Embodiment which concerns on this invention. It is a fragmentary perspective view of the ring member in the bearing unit of the modification of 4th Embodiment which concerns on this invention. It is principal part sectional drawing of the bearing unit of 5th Embodiment which concerns on this invention. It is principal part sectional drawing of the bearing unit used for the penetration oil amount comparison test, (a) is principal part sectional drawing of the bearing unit of an Example, (b) is principal part sectional drawing of the bearing unit of a comparative example. It is sectional drawing of the conventional bearing unit. It is sectional drawing of the bearing unit of patent document 1. FIG.

Explanation of symbols

10, 10A, 10B, 10C, 10D, 10E Bearing unit 20 Deep groove ball bearing (rolling bearing)
21 Inner ring 22 Outer ring 23 Ball 24 Cage 30 Housing 31 Projection 40 Rotating shaft (axis)
50 Lubricating oil intake part 32, 72, 82 Tapered surface (tapered part)
62 steps 70 ring member 80 collar

Claims (4)

An inner ring, an outer ring, and a plurality of rolling elements disposed between the inner ring and the outer ring so as to be freely rollable in the circumferential direction, are lubricated from a shaft on which a lubricating oil supply port is formed and the inner ring is fitted externally. In rolling bearings where oil can be supplied,
A lubricating oil intake portion that extends radially inward from the inner peripheral surface of the outer ring and converts the flow of the lubricating oil discharged from the lubricating oil supply port to the rolling bearing side in the vicinity of the position facing the lubricating oil supply port Is provided,
The lubricating oil intake portion includes a tapered portion that gradually increases in diameter toward the rolling bearing side, an inner peripheral surface that extends substantially parallel to the shaft and is positioned on the inner diameter side of the tapered portion, and the tapered portion. A vertical surface that connects the inner peripheral surface in the radial direction,
The distance between the shaft and the inner circumferential surface, rather short than the distance between the vertical surface and the inner ring end face,
The inner peripheral surface is opposed to the shaft through a gap,
The rolling bearing according to claim 1, wherein the lubricating oil flowing into the bearing is discharged to a side opposite to the lubricating oil intake portion .   The rolling bearing according to claim 1, wherein the lubricating oil intake portion is formed in the outer ring. A rolling bearing according to claim 1 ;
In a bearing unit comprising a housing in which the outer ring is fitted,
The bearing unit, wherein the lubricating oil intake portion is formed in the housing. A rolling bearing according to claim 1 ;
A housing in which the outer ring is fitted;
In a bearing unit comprising a ring member between the housing and the rolling bearing in the axial direction,
The bearing unit, wherein the lubricating oil intake portion is formed in the ring member.

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