JP2009287678A - Roller bearing and bearing structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a roller bearing improved in service life. <P>SOLUTION: A cylindrical roller bearing 7 comprises: an inner ring 2 provided with an inner ring raceway 2k outside in the radial direction; an outer ring 1 provided with an outer ring raceway 1k inside in the radial direction; and a plurality of rollers 4 arranged between the inner ring 2 and the outer ring 1. An axial end of the outer ring raceway 1k is provided with a relief groove 20 extending in the circumferential direction. The outer diameter surface 1g of the outer ring 1 is provided with a recessed part 21 recessed inside in the radial direction to store lubricating oil. The outer ring 1 is provided with an oil communication hole 22 passing through the outer ring 1 to connect the recessed part 21 and the relief groove 20 to each other so that the lubricating oil passes there through. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a roller bearing and a bearing structure, and more particularly to a roller bearing and a bearing structure used in an aircraft jet engine.

  A bearing that supports a main shaft of a gas turbine engine such as an aircraft jet engine rotates at a high speed and is used under a high temperature condition. Therefore, in order to prevent seizure of the bearing, deformation due to heat generation, and the like, a mechanism for supplying lubricating oil for cooling and lubrication from the outside of the bearing to the inside of the bearing is provided.

  Further, it is required that the bearing can be used in the same way as the normal time when the lubricating oil is supplied even when the oil supply is cut off in the event of an emergency, or when the so-called lubricating oil is not supplied from the outside.

  Here, in such a dry run, a bearing that efficiently uses the lubricating oil accumulated in the bearing is disclosed in Japanese Patent Laid-Open No. 2006-316846 (Patent Document 1).

According to Patent Document 1, the bearing includes an inner ring, an outer ring, a plurality of rolling elements disposed between the inner ring and the outer ring, and a cage that holds the plurality of rolling elements. And the oil groove which stores lubricating oil is provided in the internal diameter surface of the outer ring | wheel located in the axial direction both sides of a track surface, or the internal diameter surface of the holder | retainer located in the axial direction both sides of the pocket which accommodates a rolling element. The oil groove has a shape with a narrow opening width, and a plurality of oil grooves are provided in the axial direction. The bearings prevent the seizure of the bearings and the like by storing the lubricating oil in this oil groove at normal times when the lubricating oil is supplied, and appropriately supplying the lubricating oil stored in the oil groove during dry running into the bearing. It is said.
Japanese Patent Laying-Open No. 2006-316846 (FIGS. 1 and 2)

  In the bearing disclosed in Patent Document 1, since the raceway surface is provided on the inner diameter surface of the outer ring, a region for providing an oil groove in the axial direction must be secured in order to store a large amount of lubricating oil. Therefore, it is difficult to secure a sufficient area for providing the oil groove. Moreover, since the pocket for accommodating a rolling element is provided also in the internal diameter surface of a holder | retainer, it is difficult to ensure sufficient area | region for providing an oil groove. As a result, the number of oil grooves is reduced, and sufficient lubricating oil cannot be stored. In dry running, the lubricating oil is insufficient and seizure or the like occurs, thereby shortening the bearing life.

  An object of the present invention is to provide a roller bearing capable of extending the life.

  Another object of the present invention is to provide a bearing structure capable of extending the life.

  The roller bearing according to the present invention includes an inner ring having an inner ring raceway surface provided radially outward, an outer ring having an outer ring raceway surface radially provided, and a plurality of rollers disposed between the inner ring and the outer ring. Prepare. The outer ring raceway surface is provided with a circumferentially extending groove at the axial end, and the outer ring outer diameter surface is provided with a recess recessed radially inward to store lubricating oil. Is provided with an oil passage hole that penetrates the outer ring so as to connect the recess and the thin groove and allows the lubricating oil to pass therethrough.

  Thus, since the recessed part which accumulates lubricating oil is provided in the outer diameter surface of an outer ring | wheel, a recessed part can be provided without considering a track surface. Therefore, a large amount of lubricating oil can be stored. And since the lubricating oil collected in the recessed part is supplied to the inside of a bearing from a thin groove through an oil passage hole, lubricating oil can be appropriately supplied to the inside of a bearing. Therefore, by using the accumulated lubricating oil, it is possible to prevent seizure or the like and extend the life.

  As one embodiment, the oil passage hole is provided so as to extend in a direction perpendicular to the rotation axis direction of the roller bearing. By doing so, the lubricating oil can be easily supplied into the bearing.

  As another embodiment, the oil passage hole is provided so as to extend obliquely with respect to the rotation axis direction of the roller bearing.

  More preferably, a plurality of oil passage holes are provided. By carrying out like this, lubricating oil can be supplied to each part of a bearing.

  More preferably, each of the plurality of oil passage holes is equally arranged in the circumferential direction. By doing so, the lubricating oil can be supplied uniformly in the circumferential direction.

  In another aspect of the present invention, a bearing structure includes any of the roller bearings described above, and a housing having an oil passage that is provided radially outside the roller bearing and supplies lubricating oil to the recess. . Since such a bearing structure includes the roller bearing described above, it is possible to extend the life.

  Preferably, the supply amount of the lubricating oil per unit time supplied to the recess through the oil passage at a normal time is more than the supply amount of the lubricant oil per unit time supplied from the recess to the inside of the bearing through the oil passage hole. Adjusting means for adjusting to increase is provided. By doing so, the lubricating oil can be reliably accumulated in the recess during normal operation.

  Since the roller bearing according to the present invention is provided with a recess for storing lubricating oil on the outer diameter surface of the outer ring, the recess can be provided without considering the raceway surface. Therefore, a large amount of lubricating oil can be stored. And since the lubricating oil collected in the recessed part is supplied to the inside of a bearing from a thin groove through an oil passage hole, lubricating oil can be appropriately supplied to the inside of a bearing. Therefore, by using the accumulated lubricating oil, it is possible to prevent seizure or the like and extend the life.

  In addition, since the bearing structure according to the present invention includes the above-described roller bearing, the life can be extended.

  Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a longitudinal sectional view showing a bearing structure 10 including a cylindrical roller bearing 7 according to an embodiment of the present invention. A plurality of cylindrical roller bearings 7 are attached to a main shaft of a helicopter engine, a main shaft of an aircraft jet engine, and the like, and rotatably support the main shaft.

  The bearing structure 10 includes a cylindrical roller bearing 7 and a housing 11 provided on the radially outer side of the cylindrical roller bearing 7.

  The housing 11 has an oil passage 23 for supplying lubricating oil.

  The cylindrical roller bearing 7 is disposed in an annular region 3 formed between the inner ring 2 fitted to the main shaft 6 and rotating at a high speed together with the main shaft 6, the outer ring 1 fixed to the housing 11, and the inner ring 2 and the outer ring 1. A plurality of cylindrical rollers 4 and a cage 5 that holds the circumferential intervals of the plurality of cylindrical rollers 4 constant.

  The inner ring 2 is provided with inner ring collar portions 9 that protrude radially outward at both ends in the axial direction. Further, the inner ring 2 is provided with an inner ring raceway surface 2k on which the cylindrical rollers 4 roll on the radially outer side.

  FIG. 2 is a view of the outer ring 1 shown in FIG. 1 as viewed from the outside in the radial direction. In FIG. 2, only a part of the outer ring 1 is shown. With reference to FIGS. 1 and 2, the outer ring 1 is provided with outer ring flanges 8 protruding radially inward at both axial ends. Further, the outer ring 1 is provided with an outer ring raceway surface 1k on which the cylindrical roller 4 rolls radially inward.

  At both end portions in the axial direction of the outer ring raceway surface 1k, a cut groove 20 extending in the circumferential direction is provided. The relief groove 20 is provided in a boundary portion between the outer ring raceway surface 1k and the axially central side end face 8t of each outer ring flange 8.

  Further, a concave portion 21 that is recessed radially inward is provided on the outer diameter surface 1 g of the outer ring 1. The recess 21 has a shape continuous in the circumferential direction. The axial width of the recess 21 is larger than the axial width of the cylindrical roller 4. Lubricating oil supplied from an oil passage 23 provided in the housing 11 is supplied toward the recess 21. The recess 21 stores lubricating oil supplied from the oil passage 23.

  Further, the outer ring 1 is provided with an oil passage hole 22 that penetrates the outer ring 1 so as to connect the recess 21 and the cut groove 20 and allows lubricating oil to pass therethrough. The oil passage hole 22 has a straight shape and is provided so as to extend in a direction perpendicular to the rotation axis direction of the cylindrical roller bearing 7. In addition, the oil passage holes 22 are provided in the recess grooves 20 on both sides in the axial direction at the same position in the axial direction. A plurality of oil passage holes 22 are provided, and each of them is equally arranged in the circumferential direction. The oil passage hole 22 allows the lubricating oil stored in the recess 21 to pass therethrough.

  Here, the supply route of the lubricating oil at the normal time will be described. In addition, the normal time is a state where the lubricating oil is supplied from the outside of the bearing other than during the dry run. Lubricating oil is supplied from the oil passage 23 toward the recess 21 while the inner ring 2 and the main shaft 6 rotate at high speed. The recess 21 stores the lubricating oil supplied from the oil passage 23. Therefore, when the lubricating oil is further supplied from the oil passage 23 toward the concave portion 21, the lubricating oil accumulated in the concave portion 21 overflows from the concave portion 21 to the outer diameter surface 1 g of the outer ring 1. The overflowing lubricating oil travels from the outer diameter surface 1g of the outer ring 1 to both end surfaces 1t in the axial direction to cool the bearing.

  Next, a lubricating oil supply path during dry running will be described. During the dry run, the supply of lubricating oil from the oil passage 23 is shut off. However, during the dry run, the inner ring 2 and the main shaft 6 rotate at a high speed as in the normal state, so that the temperature of the bearing rises. As a result, the viscosity of the lubricating oil becomes lower than that at the normal time described above, so that the lubricating oil stored in the concave portion 21 at the normal time can easily flow from the oil passage hole 22. Accordingly, the lubricating oil is supplied to the inside of the bearing through the oil passage hole 22, the cut groove 20, and the like.

  As described above, the cylindrical roller bearing 7 is provided with the concave portion 21 that accumulates the lubricating oil on the outer diameter surface 1g of the outer ring 1, so that the concave portion 21 can be provided without considering the raceway surface 1k. Therefore, a large amount of lubricating oil can be stored. And since the lubricating oil collected in the recessed part 21 is supplied into the inside of a bearing from the thin groove 20 through the oil passage hole 22, lubricating oil can be appropriately supplied into the inside of a bearing. Therefore, by using the accumulated lubricating oil, it is possible to prevent seizure or the like and extend the life.

  Moreover, since the bearing structure 10 provided with such a cylindrical roller bearing 7 includes the above-described cylindrical roller bearing 7, it is possible to extend the life.

  Moreover, in this embodiment, since the oil passage hole 22 passes through the thin groove 20, the lubricating oil can be easily supplied to the peripheral surface and the end surface of the cylindrical roller 4. Further, the relief groove 20 can temporarily hold the lubricating oil flowing from the oil passage hole 22.

  In this embodiment, the oil passage hole 22 is provided so as to extend in a direction perpendicular to the rotation axis direction of the cylindrical roller bearing 7. By doing so, the lubricating oil can be easily supplied into the cylindrical roller bearing 7.

  In this embodiment, a plurality of oil passage holes 22 are provided. By doing so, lubricating oil can be supplied to each part of the cylindrical roller bearing 7.

  Further, in this embodiment, each of the plurality of oil passage holes 22 is equally arranged in the circumferential direction. By doing so, the lubricating oil can be supplied uniformly in the circumferential direction.

  In this embodiment, the axial width of the oil passage hole 22 is larger than the axial width of the cylindrical roller 4. Thereby, the quantity which accumulate | stores lubricating oil can be increased more.

  In addition, the slimming groove 20 can utilize what was formed at the time of manufacture of the outer ring | wheel 1. FIG. Specifically, when the outer ring raceway surface 1k is ground, the grindstone comes into contact with the outer ring flange portion 8 at the boundary portion between the outer ring raceway surface 1k and the axially central end surface 8t of each outer ring flange portion 8. It cannot be ground. Therefore, in order to avoid contact between the portion where the outer ring raceway surface 1 k cannot be ground and the cylindrical roller 4, a boundary portion between the outer ring raceway surface 1 k and the axially central end surface 8 t of each outer ring flange 8 is formed. Then, the relief groove 20 is formed. By doing so, it is not necessary to add a process for forming the thinning groove 20.

  Further, in a normal time, the supply amount of the lubricating oil per unit time supplied to the recess 21 through the oil passage 23 is the supply of the lubricating oil per unit time supplied from the recess 21 to the inside of the bearing through the oil passage hole 22. You may provide the adjustment means to adjust so that it may become larger than quantity. By so doing, the lubricating oil can be reliably stored in the recess 21 in normal times.

  As the adjusting means, for example, the supply amount of the lubricating oil per unit time supplied to the recess 21 through the oil passage 23 is the amount of the lubricating oil per unit time supplied from the recess 21 to the inside of the bearing through the oil passage hole 22. The number of oil passage holes 22 is adjusted so as to be larger than the supply amount. Further, the oil passage hole 22 may be adjusted by changing the size of the hole. Alternatively, the flow resistance of the oil passage hole 22 may be adjusted to be larger than the flow resistance of the oil path 23. Specifically, the flow passage resistance is increased by making the shape of the oil passage hole 22 not the straight shape described above but a complicated and complicated shape. Further, the total cross-sectional area of the oil passage 23 may be adjusted by making it larger than the total cross-sectional area of the oil passage holes 22.

  In the above embodiment, the example in which the oil passage hole 22 is provided so as to extend in a direction perpendicular to the rotation axis direction of the cylindrical roller bearing 7 has been described. You may provide so that it may incline and extend with respect to the rotation axis direction. Furthermore, you may combine what extends in a perpendicular direction, and what extends in inclination. FIG. 3 is a view showing an example in which the oil passage holes 24 are provided so as to extend obliquely with respect to the rotation axis direction of the cylindrical roller bearing 7. FIG. 3 shows only the part indicated by III in FIG. With reference to FIG. 3, the oil passage hole 24 located on one side in the axial direction is provided so as to be inclined and extend with respect to the rotational axis direction of the cylindrical roller bearing 7.

  Moreover, although the oil-permeable hole 22 demonstrated the example which is a straight shape, it may not be restricted to this but may be curvilinear.

  In the above embodiment, the example in which each of the plurality of oil passage holes 22 is equally arranged in the circumferential direction has been described. Also good.

  Further, in the above-described embodiment, the oil passage hole 22 has been described as an example in which the axial direction is provided in the thin groove 20 on both sides in the axial direction. You may provide in a different position.

  Further, in the above-described embodiment, the example in which the oil passage hole 22 is provided in each of the thin grooves 20 on both sides in the axial direction has been described. However, the present invention is not limited thereto, and only the thin groove 20 on one axial direction is provided. It may be provided.

  In the above-described embodiment, the example in which the axial width of the oil passage hole 22 is larger than the axial width of the cylindrical roller 4 has been described. However, the present invention is not limited thereto, and for example, the axial width of the cylindrical roller 4 The same width may be sufficient, and the width | variety smaller than the axial direction width of the cylindrical roller 4 may be sufficient.

  In the above-described embodiment, the example in which the concave portion 21 has a shape that is continuous in the circumferential direction has been described. However, the shape is not limited to this, and the shape may extend in the axial direction or may be annular. .

  Further, in the above-described embodiment, the example where the fillet groove 20 is provided at both axial end portions of the outer ring raceway surface 1k has been described. However, the present invention is not limited to this, and one axial end of the outer ring raceway surface 1k is provided. It may be provided only in the part.

  In the above embodiment, the example in which the cylindrical roller bearing 7 includes the cage 5 has been described. However, the present invention is not limited thereto, and the present invention can be applied to the cylindrical roller bearing 7 that does not include the cage 5.

  In the above embodiment, an example in which the present invention is applied to the cylindrical roller bearing 7 has been described. However, the present invention is not limited thereto, and rollers such as a tapered roller bearing, a self-aligning roller bearing, and a thrust roller bearing are used. It can be applied to a roller bearing provided.

  As mentioned above, although embodiment of this invention was described with reference to drawings, this invention is not limited to the thing of embodiment shown in figure. Various modifications and variations can be made to the illustrated embodiment within the same range or equivalent range as the present invention.

  The present invention is effectively used as a roller bearing and a bearing structure used for a main shaft of an aircraft jet engine.

It is a longitudinal section showing a bearing structure provided with a cylindrical roller bearing concerning one embodiment of this invention. It is the figure which looked at the outer ring | wheel shown in FIG. 1 from the radial direction outer side. It is a figure which shows the example which provided the oil-permeable hole so that it might incline and extend with respect to the rotating shaft direction of a cylindrical roller bearing.

Explanation of symbols

  1 outer ring, 1g outer ring outer diameter surface, 1t outer ring end face, 1k outer ring raceway surface, 2 inner ring, 2k inner ring raceway surface, 3 annular area, 4 cylindrical roller, 5 cage, 6 main shaft, 7 cylindrical roller bearing, 8 outer ring鍔 part, 9 inner ring heel part, 8t axial end side face of outer ring heel part, 10 bearing structure, 11 housing, 20 blind groove, 21 recess, 22, 24 oil passage hole, 23 oil passage.

Claims (7)

An inner ring having an inner ring raceway surface radially outward;
An outer ring having an outer ring raceway surface radially inward;
A roller bearing comprising a plurality of rollers disposed between the inner ring and the outer ring,
In the axial end of the outer ring raceway surface, there is provided a slotted groove extending in the circumferential direction,
On the outer diameter surface of the outer ring, a recess that is recessed radially inward and accumulates lubricating oil is provided,
A roller bearing in which the outer ring is provided with an oil passage hole that passes through the outer ring so as to connect the recess and the recess groove and allows lubricating oil to flow therethrough. The roller bearing according to claim 1, wherein the oil passage hole is provided so as to extend in a direction perpendicular to a rotation axis direction of the roller bearing. The roller bearing according to claim 1, wherein the oil passage hole is provided so as to extend obliquely with respect to a rotation axis direction of the roller bearing. The roller bearing according to claim 1, wherein a plurality of the oil passage holes are provided. The roller bearing according to claim 4, wherein each of the plurality of oil passage holes provided is equally distributed in a circumferential direction. A roller bearing according to any one of claims 1 to 5,
A bearing structure comprising: a housing provided on a radially outer side of the roller bearing and having an oil passage for supplying lubricating oil to the recess. In a normal state, the supply amount of lubricating oil per unit time supplied to the recess through the oil passage is greater than the supply amount of lubricant oil per unit time supplied from the recess to the inside of the bearing through the oil passage hole. The bearing structure according to claim 6, further comprising adjusting means for adjusting so as to be larger.

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