JP2018179234A - Rolling bearing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To avoid dry run by supplying a lubricant to a rolling contact part between and among an inner ring, an outer ring and rolling bodies even if the supply of the lubricant is stopped, and to continue rotation for a constant time.SOLUTION: In a cage 18 of a rolling bearing, rolling bodies 16 are assembled into a part of pockets 36 out of a plurality of the pockets 36, and an oil accumulation member 50 which can absorb and accumulate a lubricant, and can discharge the accumulated lubricant is assembled into the other pocket 36 except for a part of the pockets 36. The oil accumulation member 50 is assembled while separating from an outside raceway surface 20 and an inside raceway surface 24 in a radial direction.SELECTED DRAWING: Figure 3

Description

  The present invention relates to the lubrication of rolling bearings.

In the case of a rolling bearing, in order to lubricate a raceway and the like, a lubricating device may be installed outside to forcibly supply lubricating oil. Thus, while the lubricating method using the oil supply device can reliably lubricate the raceway surface etc., when the supply of lubricating oil is stopped due to a failure of the oil supply device, the lubricating oil on the raceway surface etc. Since it exhausts rapidly, it may cause problems such as burn-in at an early stage. Thus, it is called "dry run" to rotate in a state where the lubricating oil is depleted.
In applications such as aircraft, damage to rolling bearings has a large impact on safety, so as described above, even if lubricating oil supply is stopped for any reason, dry run conditions are avoided, at least The ability to sustain rotation for a minute is required.

  For example, in the rolling bearing of Patent Document 1, a self-lubricating coating such as silver is formed on the surface of a cage. In this rolling bearing, in order to guide the rotation of the cage, sliding contact is made between the outer circumferential surface of the cage and the inner circumferential surface of the outer ring. The sliding contact surface is usually lubricated with lubricating oil, but if the lubricating device breaks down and the lubricating oil is depleted, silver covering the cage intervenes in the sliding part. Prevents burn-in.

JP, 2010-2034, A

  In the cage of the rolling bearing described in Patent Document 1, a self-lubricating coating of silver or the like is formed on the entire circumference, so that it is possible to lubricate the sliding contact portion with the directly contacting outer ring even if a dry run occurs. . However, since the cage does not come in direct contact with the raceway surface, a self-lubricating substance such as silver does not easily intervene at the portion where the raceway surface and the rolling element make rolling contact. For this reason, when a dry run occurs, there is a possibility that a problem such as seizing may occur at the rolling contact portion.

  Therefore, according to the present invention, even when the supply of the lubricating oil is stopped, the lubricating oil is supplied to the rolling contact portion between the inner ring and the outer ring and the rolling element to avoid the dry run and maintain the rotation for a fixed time. The purpose is to provide a rolling bearing that can be

  According to the present invention, an outer ring having an outer raceway surface formed on the inner periphery, an inner ring having an inner raceway surface formed on the outer periphery, and a plurality of rollers disposed rollably between the outer raceway surface and the inner raceway surface A rolling bearing, and a cage having a plurality of pockets defined by a pair of axially opposed annular portions and a plurality of pillars axially connecting the annular portions, In the cage, the rolling element is assembled to some pockets of the plurality of pockets, and lubricating oil is absorbed and accumulated in the other pockets excluding the some pockets An oil storage member is assembled which can release the lubricating oil which can be accumulated and accumulated, and the oil storage member is assembled radially spaced apart from the outer raceway surface and the inner raceway surface. It is characterized by

  According to the present invention, even when the supply of lubricating oil is stopped, the lubricating oil can be supplied to the rolling contact portion between the inner ring and the outer ring and the rolling element to avoid dry run and maintain rotation for a fixed time. A bearing can be provided.

It is an axial sectional view of this embodiment. It is an explanatory view explaining composition of a holder. It is a principal part enlarged view of the cross section in the position of XX of FIG. It is sectional drawing in the position of YY of FIG.

One embodiment of the present invention (hereinafter, the present embodiment) will be described in detail with reference to the drawings. FIG. 1 is an axial sectional view of a rolling bearing 10 according to the present embodiment. The rolling bearing 10 is a cylindrical roller bearing, and is used, for example, for supporting a main shaft of a jet engine of an aircraft.
The rolling bearing 10 includes an outer ring 12, an inner ring 14, a plurality of cylindrical rollers 16 as rolling elements, and a cage 18. The outer ring 12 and the inner ring 14 are respectively annular and coaxially combined, and the inner ring 14 is rotatable inside the outer ring 12. In the following description, the direction of the bearing center axis O is referred to as the axial direction, the direction orthogonal to the bearing center axis O is referred to as the radial direction, and the direction around the bearing center axis O is referred to as the circumferential direction.

  The outer ring 12 is made of heat-resistant alloy steel such as M50. An outer raceway surface 20 is formed on the inner peripheral side. The outer raceway surface 20 has a cylindrical shape, and a radially inward projecting weir 22 is provided on both axial outer sides thereof. The axially inner side surface 22 a of each weir 22 serves as a guide surface when the cylindrical roller 16 rolls in the circumferential direction. Further, the inner circumferential surface 22 c of the weir 22 is a cylindrical surface coaxial with the outer raceway surface 20 and serves as a guiding surface when the cage 18 rotates.

  The inner ring 14 is made of heat-resistant alloy steel such as M50. A cylindrical inner raceway surface 24 is formed on the outer peripheral side.

  The cylindrical roller 16 is made of heat-resistant alloy steel such as M50. The outer peripheral surface 26 has a cylindrical shape, and a pair of end surfaces 27 and 27 which are orthogonal to the central axis of the cylindrical roller 16 and are parallel to each other are formed at both ends in the axial direction. The cylindrical roller 16 is disposed so as to be rotatable in the circumferential direction between the outer raceway surface 20 and the inner raceway surface 24, and rotatably supports the inner race 14 with respect to the outer race 12.

FIG. 2 is an explanatory view for explaining the configuration of the holder 18.
The cage 18 is annular and made of nickel chromium molybdenum steel. The outer peripheral surface 30 (see FIG. 1) has a cylindrical shape, and its outer diameter is slightly smaller than the inner diameter of the crucible 22. As shown in FIG. 2, the cage 18 includes a pair of annular portions 32 and 32 axially spaced apart and coaxially formed, and a plurality of pillar portions 34 axially connecting the annular portions 32. ing. Thus, a plurality of radially penetrating pockets 36 are formed side by side in the circumferential direction by being defined by the pair of annular portions 32 and the pair of column portions 34 adjacent in the circumferential direction.

In the present embodiment, the oil storage member 38 is integrally incorporated in a pair of pockets 36, 36 which are radially opposed with the bearing center axis O interposed therebetween. In the following description, the pair of pockets 36 is referred to as pocket A and pocket B, respectively.
The oil storage member 38 has a cylindrical outer peripheral surface 50, and is integrally assembled with the holder 18 by a pin 42 as a support member. The pocket A shows the state before the oil storage member 38 is assembled, and the pocket B shows the state after the oil storage member 38 is assembled. Details of the oil accumulation member 38 will be described later.

One cylindrical roller 16 (not shown in FIG. 2) is inserted in each of the pockets 36 except the pockets A and B in which the oil accumulation member 38 is incorporated. The axial dimension of the pocket 36 is slightly larger than the axial dimension of the cylindrical roller 16. Further, when the cylindrical roller 16 is inserted into the pocket 36 and the cylindrical roller 16 is brought into contact with one of the column portions 34, the cylindrical roller 16 does not come in contact with the other column portion. Thus, the cylindrical rollers 16 are rotatable in each pocket 36.
Thus, the cylindrical roller 16 is disposed at a predetermined distance between the outer raceway surface 20 and the inner raceway surface 24 by the cage 18.

  FIG. 3 is an enlarged view of an essential part in which the cross section in the direction orthogonal to the bearing center axis O is viewed in the axial direction at the position of XX in FIG. 1. Two wings 44 and 44 are formed on the inner circumferential side of each column 34. Each wing 44 extends along the outer peripheral surface 26 of the cylindrical roller 16 inserted in the pocket 36 toward the inside of the pocket 36. The distance h between a pair of wings 44 formed on both sides in the circumferential direction of each pocket 36 is smaller than the outer diameter dimension d0 of the cylindrical roller 16. Therefore, it is possible to prevent the cylindrical roller 16 from falling off the pocket 36 at the time of assembly of the rolling bearing 10.

  The oil storage member 38 will be described in detail with reference to FIG. FIG. 4 is an axial cross-sectional view at a position Y-Y in FIG. 3 and shows a cross section of the oil accumulation member 38. As shown in FIG.

The oil accumulation member 38 is formed of a cylindrical core member 46 formed of metal or resin, and an oil holding portion 48 attached to the outer periphery of the core member 46 and covering the core member 46. In the core 46, a support hole 40 penetrating in the axial direction of the core 46 is formed.
The oil holding portion 48 of the present embodiment is a sponge-like sponge, and is manufactured by foam-molding a synthetic resin material such as polyurethane. The sponge thus produced is porous and has numerous fine pores formed therein. For this reason, when immersed in a liquid such as lubricating oil, the liquid is absorbed inside the sponge by capillary action. In addition, by applying external force to the sponge, the absorbed liquid can be easily released to the outside.

  As a material of the oil holding portion 48, a cloth base phenol resin laminated tube in which a cloth as a main base and a phenol resin as a binder are formed into a circular tube shape in addition to a resin material (JIS K 6914 PTR-FCM) Or, felt, sintered metal, etc. can be used. These materials have numerous fine pores formed therein, and can absorb and release lubricating oil. In addition, the material of the oil holding | maintenance part 48 is an illustration, Comprising: It is not limited to these. The oil storage member 38 may be entirely formed of a porous material such as a sponge, including the oil holding portion 48 and the core 46.

  As shown in FIG. 3, the outer diameter dimension d1 of the oil storage member 38 is smaller than the outer diameter dimension d0 of the cylindrical roller 16 (d1 <d0). Thus, the outer circumferential surface 50 is held with the outer raceway surface 20 and the inner raceway surface 24 with gaps s1 and s2 in the radial direction, and is not in contact with the outer raceway surface 20 and the inner raceway surface 24.

As mentioned above, the oil accumulation member 38 is supported by the pin 42.
In the pockets A and B in which the oil storage member 38 is assembled, the pin holes 41 penetrating in the axial direction are formed in the pair of annular portions 32 defining the pocket 36. The pin holes 41, 41 respectively provided in the pair of annular portions 32 are formed on one straight line parallel to the central axis of the cage 18.
After the oil storage member 38 is inserted into the pockets A and B, the pin 42 is inserted through the pin holes 41 and 41 and the support hole 40. The pin 42 is fitted into the pin hole 41 in an interference fit. The entire length of the pin 42 is slightly shorter than the full width in the axial direction of the retainer 18, and the pin 42 is prevented from falling off by being crimped in the opening of the pin hole 41 after being fitted into the pin hole 41.
Further, the inner diameter of the support hole 40 is set to be slightly larger than the outer diameter of the pin 42, and the oil storage member 38 is rotatable around the pin 42.

  Thus, the oil storage member 38 is held integrally with the holder 18 by the pin 42. Assuming that the oil accumulation member 38 is inserted into the pocket 36 similarly to the cylindrical roller 16 without providing the pin 42, when the rolling bearing 10 is assembled, between the wing 44 and the wing 44 facing in the circumferential direction There is a risk of falling off from the gap. In the rolling bearing 10 of the present embodiment, since the oil storage member 38 is assembled integrally with the cage 18 by the pin 42, there is no risk of falling off, and the assembling property of the rolling bearing 10 is improved.

  The holding member for holding the oil storage member 38 may be a bolt. In this case, although not shown, bolt holes and screw holes are formed in the annular portion 32 axially defining the pockets A and B in the same direction as the pin holes 41 in FIG. 4. The bolt hole is formed in the annular portion 32 on one side in the axial direction, and the inner diameter dimension is larger than the outer diameter dimension of the bolt. The screw hole is formed in the annular portion 32 on the other side in the axial direction. The oil accumulation member 38 is held integrally with the retainer 18 by tightening the bolts through the bolt holes and the support holes 40.

Thus, in the rolling bearing 10, the outer race 12 and the inner race 14 are rotatably supported by the cylindrical rollers 16 and the oil storage member 38 holding the lubricating oil is integrally assembled with the retainer 18.
When the inner ring 14 rotates relative to the outer ring 12, the cylindrical roller 16 rolls around the outer raceway surface 20 and the inner raceway surface 24 and revolves around the bearing center axis O. Since each cylindrical roller is incorporated in the pocket 36 of the cage 18, the cage 18 rotates around the bearing center axis O with the movement of the cylindrical roller 16. The outer peripheral surface 30 of the cage 18 is guided by the inner peripheral surface 22 c of the ridge 22 of the outer ring 12, and can rotate coaxially with the outer ring 12. At this time, the oil accumulation member 38 revolves around the bearing central axis O together with the cage 18.

Next, the operation of this embodiment will be described with reference to FIG.
The rolling bearing 10 is supplied with lubricating oil by a pump (not shown). The lubricating oil flows into an annular space K radially interposed between the inner periphery of the outer ring 12 and the outer periphery of the inner ring 14. As a result, the rolling contact portion between the outer raceway surface 20 and the inner raceway surface 24 and the cylindrical roller 16 is lubricated, and a large amount of lubrication is constantly applied to the oil accumulation member 38 integrally assembled to the cage 18. Oil is supplied. As described above, the oil accumulation member 38 is provided with the oil holding portion 48 which is porous and has numerous fine holes formed therein. Therefore, the lubricating oil supplied to the oil accumulation member 38 is absorbed by the fine holes by capillary action. Thus, the rolling bearing 10 rotates in a state in which the oil accumulation member 38 holds a large amount of lubricating oil.

Next, the case where the supply of lubricating oil from the supply pump is stopped for some reason will be described.
When the supply of the lubricating oil is stopped, the lubrication state of the rolling contact portion between the outer raceway surface 20 and the inner raceway surface 24 and the cylindrical roller 16 is rapidly deteriorated. In the case where no measure is taken, the lubricating oil is depleted, so the rolling contact portion of the rolling bearing 10 is in a dry run state.

In the rolling bearing 10 of the present embodiment, since the inner ring 14 continues to rotate, the oil storage member 38 integrally assembled with the cage 18 rotates around the bearing center axis O together with the cage 18. ing.
Since a large amount of lubricating oil is held in the oil accumulation member 38, when the supply of the lubricating oil from the supply pump is stopped and the lubricating oil does not exist around the oil accumulation member 38, The lubricating oil held by the oil accumulation member 38 is discharged by centrifugal force, and splashes radially outward and adheres to the radially outer outer raceway surface 20.
Since the oil accumulation member 38 is provided at the same axial position as the cylindrical roller 16, the cylindrical roller 16 reliably rolls on the outer raceway surface 20 to which the lubricating oil adheres. Therefore, lubricating oil can be effectively supplied to the rolling contact portion between the outer raceway surface 20 and the cylindrical roller 16. Furthermore, since the lubricating oil adhering to the outer peripheral surface 26 of the cylindrical roller 16 moves to the inner raceway surface 24 with the rotation of the cylindrical roller 16, lubricating the contact portion between the inner raceway surface 24 and the cylindrical roller 16 it can.
Thus, in the rolling bearing 10 of the present embodiment, even when the supply of lubricating oil from the supply pump is stopped, the rolling contact portion between the outer raceway surface 20 and the inner raceway surface 24 and the cylindrical roller 16 is maintained for a fixed time , Lubricating oil can be supplied.

Further, in the present embodiment, the oil accumulation member 38 is not in contact with the outer raceway surface 20 and the inner raceway surface 24. For this reason, the oil accumulation member 38 does not increase the rotational resistance of the rolling bearing 10.
When the inner ring 14 rotates, the cage 18 rotates in the same direction as the inner ring 14, and the rotational speed of the cage 18 is approximately one half of the rotational speed of the inner ring 14. Therefore, assuming that the oil storage member 38 contacts either the outer raceway surface 20 or the inner raceway surface 24, the sliding friction at the contact portion causes the rotational resistance of the member having the larger rotation speed to be increased. The disadvantage is that the energy is increased and the energy for rotating the device is increased.
On the other hand, in the rolling bearing 10 of the present embodiment, since the oil storage member 38 does not contact the outer raceway surface 20 and the inner raceway surface 24, the rotation resistance of the rolling bearing 10 is not increased, and the device is rotated. It is possible to prevent an increase in energy for

  In the present embodiment, the oil storage member 38 is rotatable around the pin 42. Therefore, even if the oil storage member 38 contacts the outer raceway surface 20 and the inner raceway surface 24, the oil storage member 38 is rotated around the pin 42 by the rotation of the inner ring 14 or the outer ring 12. Or, there is no sliding contact between the inner ring 14 and the cage 18. In particular, in the present embodiment, since the outer circumferential surface 50 of the oil accumulation member 38 has a cylindrical shape, when in contact with each of the raceway surfaces 20 and 24, rolling contact is made smoothly. Therefore, the rotational resistance of the inner ring 14 or the outer ring 12 does not increase, and the energy of rotating the device does not increase.

Further, in the rolling bearing 10 of the present embodiment, when the supply of the lubricating oil from the supply pump is stopped, the lubricating oil absorbed in advance in the oil accumulation member 38 is released and supplied to the rolling contact portion. .
Generally, the characteristics of the lubricating oil used to lubricate the rolling bearing 10 largely change depending on the oil type, additives and the like. For this reason, in the rolling bearing 10 used for an aircraft etc., the suitable lubricating oil is selected according to the use conditions, for example, the atmospheric temperature, the rotational speed, the magnitude of the load, and the like.

Assuming that an oil-impregnated resin impregnated with another lubricating oil beforehand is used as the oil accumulation member 38, the lubrication supplied to the rolling contact surface after the supply of the lubricating oil from the supply pump is stopped. The oil will be different from the lubricating oil previously supplied. For this reason, when the supply of the lubricating oil from the supply pump is stopped, the lubricating oil of a type different from the lubricating oil properly selected according to the use condition is supplied, so the lubricating performance is sufficiently exhibited. It can not be done, and there is still a possibility that a problem such as seizing may occur in the rolling contact portion.
On the other hand, in the present embodiment, even when the supply of lubricating oil from the supply pump is stopped, the rolling contact portion is supplied with the same lubricating oil as the lubricating oil that was supplied before the supply was stopped. can do. For this reason, generation | occurrence | production of malfunctions, such as a seizure in a rolling contact part, can be prevented reliably.

  The mass of the oil accumulation member 38 is increased by holding a large amount of lubricating oil. In the present embodiment, the oil storage member 38 is incorporated in the pocket 36 formed at a position facing in the radial direction of the retainer 18. For this reason, the mass of the retainer 18 is uniform in the circumferential direction, and it is possible to suppress the occurrence of vibration or the like due to unbalance. In the present embodiment, the oil storage members 38 are provided in the two pockets A and B facing in the radial direction, but the oil storage members 38 may be assembled equally in three or more in the circumferential direction. Since the load bearing performance of the rolling bearing 10 is reduced by reducing the number of cylindrical rollers 16, it is desirable to set the number of oil storage members 38 to one third or less of the total number of pockets.

  As described above, in the rolling bearing 10 of the present embodiment, even if the supply of lubricating oil is stopped, the lubricating oil is supplied to the rolling contact portion between the inner ring 14 and the outer ring 12 and the cylindrical roller 16 to perform dry running. Can be avoided and the rotation can be maintained for a fixed time.

In this embodiment, although the rolling bearing 10 demonstrated the cylindrical roller bearing whose rolling element is a cylindrical roller, it is not limited to this. For example, it can be applied to various types of rolling bearings such as deep groove ball bearings, tapered roller bearings, spherical roller bearings and the like.
Further, the present invention is not limited to the above-described embodiment, and various other modifications are possible.

10: rolling bearing, 12: outer ring, 14: inner ring, 16: cylindrical roller, 18: cage, 20: outer raceway surface, 22: weir, 24: inner raceway surface, 32: annular portion, 34: post, 36 : Pocket, 38: Oil accumulation member, 40: Support hole, 42: Pin, 46: Core material, 48: Oil holding portion

Claims (3)

An outer ring having an outer raceway surface formed on the inner periphery,
An inner ring having an inner raceway formed on the outer periphery,
A plurality of rolling elements rollably disposed between the outer raceway surface and the inner raceway surface;
A rolling bearing comprising: a pair of axially opposed annular portions; and a cage having a plurality of pockets defined by a plurality of pillars axially connecting the annular portions, the roller bearing comprising:
In the cage, the rolling element is assembled to some pockets of the plurality of pockets, and lubricating oil is absorbed and accumulated in the other pockets excluding the some pockets An oil accumulation member capable of releasing the accumulated lubricating oil is assembled.
The rolling bearing characterized in that the oil storage member is radially spaced apart from the outer raceway surface and the inner raceway surface.   The oil storage member is supported integrally with the retainer by a support member which is bridged in the axial direction of the retainer by the pair of annular portions, and is rotatable around the support member. The rolling bearing of claim 1. The rolling bearing according to claim 1 or 2, wherein the oil storage member comprises an oil holding portion made of a sponge-like sponge.

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