JP2007100775A - Thrust cylindrical roller bearing - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To achieve a structure suppressing the wear of an outer diameter side peripheral edge of each pocket 7 provided in a retainer 2a at low cost. <P>SOLUTION: Displacement of the retainer 2a to one edge side in the axial direction is regulated by engagement of engagement parts 18 and 19 on the outer and inner diameter sides, respectively, and a raceway face 10 of each cylindrical roller 8. Further, displacement of the retainer 2a to the other edge side in the axial direction is regulated by engaging the outer faces of the both flat plate parts 14 and 15 on the outer and inner diameter sides, respectively, and a race face of a race 25b. δ which is a roller protruding amount is made smaller than a radial direction length W of a chamfering part 11 of the cylindrical roller 8. The radial direction length W of the chamfering part 11 is made smaller than a thickness T of a metallic plate structuring the retainer 2a. By the above measures, the problem can be solved. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an improvement of a thrust cylindrical roller bearing incorporated in a rotation support portion of various mechanical devices such as an automobile transmission, a car air conditioner compressor, and a machine tool. Specifically, regarding the improvement of a thrust cylindrical roller bearing with a cage that can be manufactured at low cost by punching and bending a single metal plate, the wear of this cage is reduced and excellent durability is achieved. The structure which has this is implement | achieved. The thrust cylindrical roller bearing that is the subject of the present invention includes a thrust needle bearing that uses a needle (needle roller) having a larger axial dimension than the outer diameter as a rolling element. Therefore, the cylindrical roller described in the present specification and claims includes the needle.

  As a thrust cylindrical roller bearing provided with a cage that can be manufactured at a low cost by punching and bending a single metal plate, techniques described in Patent Documents 1 to 5 are known. FIGS. 5 to 9 show a first example of a thrust cylindrical roller bearing 1 having a conventional structure, which is known as described in each of these patent documents. The thrust cylindrical roller bearing 1 includes one cage 2 and a plurality of cylindrical rollers 8 and 8. The cage 2 is integrally formed by bending a metal plate such as a steel plate, and has a cylindrical inner diameter side rim portion 4, a cylindrical outer diameter side rim portion 5, and an intermediate plate portion 6. And a plurality of pockets 7,7.

  Among these, the inner diameter side rim portion 4 is present at the inner peripheral edge portion of the cage 2 and has an annular shape continuous over the entire circumference. Further, the outer diameter side rim portion 5 is present on the outer peripheral edge portion of the cage 2 and has an annular shape that is concentric with the inner diameter side rim portion 4 and is continuous over the entire circumference. Further, the intermediate plate portion 6 exists between the inner diameter side rim portion 4 and the outer diameter side rim portion 5, and the cross-sectional shape is bent with respect to the radial direction. Further, each of the pockets 7 and 7 is formed in the intermediate plate portion 6 intermittently in the radial direction with respect to the circumferential direction, and holds the cylindrical rollers 8 and 8 in a freely rollable manner inside each. To do.

As shown in FIG. 6, a central flat surface 9 extending in a direction perpendicular to the rotation center axis of each cylindrical roller 8, 8, and the central flat surface 9 A chamfered portion 11 having a partially conical convex surface shape or a convex curved surface shape having a partially convex arc shape is formed, which continues the outer peripheral edge and the rolling surface 10 over the entire circumference. In the case of the conventional structure, among the dimensions of the chamfered portion 11, the axial dimension L ₈ and the radial dimension W _{8 of} each cylindrical roller 8 are substantially equal (L ₈ ≈W ₈ ). Further, in the intermediate plate portion 6, the portions between the pockets 7, 7 adjacent in the circumferential direction are column portions 12, 12.

  The intermediate plate portion 6 includes a central flat plate portion 13, an outer diameter side flat plate portion 14, an inner diameter side flat plate portion 15, an inner diameter side continuous portion 16, and an outer diameter side continuous portion 17. Among these, the central flat plate portion 13 is a portion close to one end in the axial direction (the lower end of FIGS. 5, 7, 9) in the radial direction (the left-right direction in FIGS. 5, 7, the up-down direction in FIG. 8, the front-back direction in FIG. 9). Is formed. Further, the outer diameter side flat plate portion 14 is formed at a portion closer to the other end in the axial direction (upper end in FIGS. 5, 7 and 9) adjacent to the radially inner side (left side in FIG. 7) of the outer diameter side rim portion 5. Has been. Further, the inner diameter side flat plate portion 15 is formed in a portion near the other end in the axial direction adjacent to the radially outer side (right side in FIG. 7) of the inner diameter side rim portion 4. The outer diameter side and inner diameter side flat plate portions 14 and 15 are located on the same plane. Further, the inner diameter side continuous portion 16 continues the outer peripheral edge of the inner diameter side flat plate portion 15 and the inner peripheral edge of the central flat plate portion 13, and the outer diameter side continuous portion 17 is an outer periphery of the central flat plate portion 13. The peripheral edge and the inner peripheral edge of the outer diameter side flat plate portion 14 are made continuous. The distance between the inner diameter side and outer diameter side continuous portions 16 and 17 increases as the distance from the central flat plate portion 13 increases. The outer surface of the central flat plate portion 13 (the lower surface in FIGS. 5, 7, and 9) and the leading edges of the inner diameter side and outer diameter side rim portions 4, 5 are located on the same plane, or the central flat plate The outer surface of the portion 13 protrudes in the axial direction from the tip edge.

  The cage 2 configured as described above is a pair of race surfaces constituting the thrust cylindrical roller bearing 1 in a state where the cylindrical rollers 8 and 8 are rotatably held in the respective pockets 7 and 7. It is sandwiched between a pair of parallel planes facing each other in the axial direction. Among the flat plate portions 13 to 15 constituting the intermediate plate portion 6, the circumferential edge portions of the column portions 12 and 12 are the inner diameter side and the outer diameter side. Compared to the side edge portions of both continuous portions 16 and 17, they protrude slightly into the pockets 7 and 7.

  That is, in the outer diameter side flat plate portion 14 at the radially outer position and the inner diameter side flat plate portion 15 at the radially inner position, the circumferential end edges of the column portions 12 and 12 are respectively set on the outer diameter side. The locking portions 18 and 18 and the inner diameter side locking portions 19 and 19 are provided. Then, as shown in FIGS. 7 and 9 (A), the engagement between the outer diameter side and inner diameter side locking portions 18 and 19 and the rolling surfaces 10 of the cylindrical rollers 8 makes these cylinders. The axial direction of the cage 2 is such that a part of the roller 8 remains in the axial direction protruding from the central flat plate portion 13 and the leading edge of the inner diameter side and outer diameter side rim portions 4, 5. The axial displacement to one end side (the lower side in FIGS. 7 and 9) is restricted.

Further, in the central flat plate portion 13 at the intermediate position in the radial direction, the circumferential edge portions of the column portions 12 and 12 are set as central locking portions 20 and 20, respectively. Then, as shown in FIGS. 7 and 9B, due to the engagement between the central locking portions 20 and 20 and the rolling surfaces 10 of the cylindrical rollers 8, a part of the cylindrical rollers 8 is Axial displacement of the cage 2 toward the other axial end (upper side in FIGS. 7 and 9) so that the outer and inner diameter flat plate portions 14 and 15 remain protruding in the axial direction. Is regulated.
In short, in a state where the cylindrical rollers 8 and 8 are held in the pockets 7 and 7, the locking portions 18 to 20 and the rolling surfaces 10 of the cylindrical rollers 8 and 8 are engaged with each other. The axial displacement of the cage 2 with respect to the cylindrical rollers 8 and 8 is suppressed. That is, the positioning of the cage 2 in the axial direction is achieved by so-called roller guides (both side rollers are provided).

  By the way, when the thrust cylindrical roller bearing 1 as described above is used, a force directed radially outward of the cage 2 is applied to the cylindrical rollers 8 and 8 based on the centrifugal force. And by this force, the outer diameter side end surface 21 which becomes the radial direction outer side of the cage 2 among the axial direction both end surfaces of the cylindrical rollers 8 and 8 is the outer peripheral side portion of the pockets 7 and 7. The retainer 2 is pressed against the outer peripheral side peripheral edge 22 which is the radially outer side. As a result, the outer diameter side peripheral edge 22 and the outer diameter side end face 21 rub against each other at the portion indicated by the oblique lattice in FIG. However, the outer diameter side end face 21 is not uniformly pressed against the outer diameter side peripheral edge 22. In an actual case, the outer diameter side end surface 21 is pressed against the outer diameter side peripheral edge portion 22 due to the skew of the cylindrical rollers 8, 8 in the pockets 7, 7. In contact with each other.

  That is, when the thrust cylindrical roller bearing 1 is operated, it is ideal that the direction of the rotation axis of each of the cylindrical rollers 8 and 8 and the radial direction of the cage 2 coincide with each other. These two directions are inevitably inconsistent with each other. Such a skew is caused by the friction coefficient of the rolling contact portion between the rolling surface 10 of each of the cylindrical rollers 8 and 8 and the race surface being non-uniform in the length direction of the rolling contact portion. Further, the degree of contact between the outer diameter side end face 21 and the outer diameter side peripheral edge 22 becomes more significant as the deviation angle (skew angle) in both directions increases.

  While the cylindrical rollers 8 and 8 are skewed, a boundary portion between the outer peripheral edge portion of the central flat surface 9 and the chamfered portion 11 and the outer diameter side peripheral edge portion 22 in the outer diameter side end surface 21. When the two rub against each other, local stress concentration occurs in the rubbed portion (the contact surface pressure P increases), and rubs at a high rub-off speed V (the PV value that is a parameter associated with wear increases). Furthermore, it becomes difficult to form an oil film for lubrication in the rubbing portion, and metal contact is likely to occur in the rubbing portion. As a result, a part of the cage 2 made of a soft metal compared to the bearing steel constituting each of the cylindrical rollers 8 and 8, the outer peripheral side peripheral portion 22 portion, as shown in FIG. A recessed portion 23 is formed in which the degree of wear is remarkable on both sides in the circumferential direction of the cage 2.

  When such a recessed portion 23 becomes large to some extent, a chamfered portion 11 provided on the outer peripheral edge of the retainer 2 in the radial direction at a part of each of the cylindrical rollers 8, 8 is formed in the recessed portion 23. While entering, a so-called submergence occurs that is displaced radially outward of the cage 2 from the original position of the pockets 7 and 7. When such subsidence occurs, the sliding resistance of the roller end surface with respect to the cage increases, and the rotational resistance of the rotational support portion incorporating the thrust cylindrical roller bearing 1 increases. Not only is the performance deteriorated, but it may cause a failure such as flaking or seizure if it is remarkable. Wear that causes such inconvenience is more likely to occur than in the past, as the speed of rotation of various mechanical devices such as transmissions and car air conditioner compressors has increased due to recent improvements in automobile performance. ing.

JP-A-6-94038 JP 2000-213546 A JP 2002-206525 A JP-A-11-351245 JP 2003-83333 A

  The present invention has been invented to realize a structure capable of suppressing wear of the outer peripheral side peripheral portion of the pocket provided in the cage in view of the above-described circumstances.

Each of the thrust cylindrical roller bearings of the present invention includes a cage and a plurality of cylindrical rollers, like the conventionally known thrust cylindrical roller bearing.
Of these, the cage is formed in an annular shape as a whole, and includes a plurality of pockets arranged in a radial direction at a plurality of locations in the circumferential direction.
The cage is integrally formed by bending a metal plate, and includes an inner diameter side rim portion, an outer diameter side rim portion, an intermediate plate portion, the respective pockets, and a plurality of column portions. Prepare.
Of these, the inner diameter side rim portion is present at the inner peripheral edge and has an annular shape continuous over the entire circumference, and the outer diameter side rim portion is present at the outer peripheral edge portion and is concentric with the inner diameter side rim portion. It is an annular shape that continues around the entire circumference.
Further, the intermediate plate portion exists between the outer diameter side rim portion and the inner diameter side rim portion, and the cross-sectional shape is bent in the radial direction, and the central flat plate portion, the outer diameter side flat plate portion, The inner diameter side flat plate portion, the inner diameter side continuous portion, and the outer diameter side continuous portion.
Among these, the central flat plate portion is formed at a portion near one end in the axial direction at the radial intermediate portion.
Further, the outer diameter side flat plate portion is formed in a portion near the other end in the axial direction adjacent to the radially inner side of the outer diameter side rim portion.
Further, the inner diameter side flat plate portion is formed in a portion near the other end in the axial direction adjacent to the radially outer side of the inner diameter side rim portion.
The inner diameter side continuous portion continuously connects the outer peripheral edge of the inner diameter side flat plate portion and the inner peripheral edge of the central flat plate portion, and the outer diameter side continuous portion includes the outer peripheral edge of the central flat plate portion and the outer diameter side. The inner peripheral edge of the flat plate portion is made continuous.
The pockets are rectangular holes that are long in the radial direction of the intermediate plate portion, and are formed in the intermediate plate portion in the radial direction intermittently in the circumferential direction.
Moreover, each said pillar part is provided between the pockets adjacent to the circumferential direction.
Further, each of the cylindrical rollers is rotatably held in each pocket of the cage.

The thrust cylindrical roller bearing according to claim 1 supports a thrust load between a pair of members having race surfaces in rolling contact with the rolling surfaces of the cylindrical rollers.
In particular, in the thrust cylindrical roller bearing according to claim 1, the axial displacement of the cage toward the one end side in the axial direction is caused by the part of the outer diameter side flat plate portion and the inner diameter side flat plate portion. Due to the engagement between the outer diameter side locking portions and the inner diameter side locking portions provided at the circumferential edge of the column portion and the rolling surfaces of the cylindrical rollers, a part of these cylindrical rollers is The inner edge side and outer diameter side rim portions are regulated so as to remain protruding in the axial direction from the leading edge of the rim portion and the central flat plate portion.
Further, the axial displacement of the cage toward the other end in the axial direction is present on the outer surface of both the outer diameter side and the inner diameter side flat plate portions, and on the other end side in the axial direction of the cage among the two members. This is regulated by engagement with a race surface formed on one member.
That is, in the case of the invention described in claim 1, a one-side roller is provided that restricts only the displacement of the cage toward one end in the axial direction by the engagement between the rolling surface of each cylindrical roller and each pocket. It is said.

Further, in the thrust cylindrical roller bearing according to claim 5, the axial displacement of the cage toward the one end side in the axial direction is caused by a part of the outer diameter side flat plate portion and the inner diameter side flat plate portion. Due to the engagement between each outer diameter side locking portion and each inner diameter side locking portion provided at the circumferential edge and the rolling surface of each cylindrical roller, a part of each of these cylindrical rollers becomes the inner diameter side, The outer edge side rim portions are regulated so as to remain in a state of protruding in the axial direction from the leading edge and the central flat plate portion.
In addition, the axial displacement of the cage toward the other end in the axial direction is caused by each central locking portion provided at the circumferential edge of each column portion and each cylinder at a part of the central flat plate portion. Engagement with the rolling surface of the roller restricts a part of each of the cylindrical rollers to protrude in the axial direction from the outer diameter side flat plate portion and the inner diameter side flat plate portion.
That is, in the case of the invention described in claim 5, both side rollers are provided to restrict displacement of the cage in the axial direction by engagement between the rolling surfaces of the cylindrical rollers and the pockets. .

In particular, in the thrust cylindrical roller bearing according to claim 5, each cylindrical roller has a rotational center of each cylindrical roller at least on an outer diameter side end surface of the cage among both axial end surfaces. A central flat surface that extends in a direction perpendicular to the axis, and a chamfered portion that continuously connects the outer peripheral edge and the rolling surface of the central flat surface over the entire circumference.
Then, in the state where the cage is displaced to one end side in the axial direction and the outer diameter side locking portions and the inner diameter side locking portions are engaged with the rolling surfaces of the cylindrical rollers, The amount that a part of the roller protrudes from the outer surface of the outer diameter side flat plate portion (the amount of roller protrusion) is made smaller than the dimension of the chamfered portion in the radial direction of each cylindrical roller.
At the same time, in a state where the cage is displaced to the other end side in the axial direction and the central locking portions and the rolling surfaces of the cylindrical rollers are engaged with each other, a part of the cylindrical rollers is outside the outer side. The difference between the amount protruding from the outer surface of the radial side flat plate portion (roller drop amount) and the dimension of the chamfered portion in the radial direction of each cylindrical roller is made smaller than the plate thickness of the metal plate.
Further, at least one of the inner diameter side rim portion and the outer diameter side rim portion is penetrated in the radial direction of the cage at a position aligned with each pocket with respect to the circumferential direction of at least one rim portion. Oil holes are formed.

  According to the present invention configured as described above, wear on the outer peripheral side edge of each pocket provided in the cage is suppressed, and the outer diameter side end of each cylindrical roller based on this wear is outside the retainer. A thrust cylindrical roller bearing can be obtained that can be prevented from entering one side of the near-diameter portion.

  That is, in the case of the invention described in claim 1, since the cage is provided with one side roller, the displacement of the cage in the axial direction is restricted by the engagement of each pocket and the rolling surface of the cylindrical roller. Compared to the structure having both side rollers, skew is more likely to occur. However, since the gap between the rolling surface of each cylindrical roller and each pocket can be made larger than that of the structure having both side rollers, it is easy to hold the oil film on the rolling surface of each cylindrical roller. Hard to be scraped off). For this reason, even if the effect of suppressing the skew is not sufficient, it is easy to form an oil film on the surface of each cylindrical roller, and the outer peripheral edge of each pocket is worn as shown in FIG. It becomes difficult to form the recessed portion due to. And it can prevent that each said cylindrical roller sinks into the said holder | retainer.

  Further, in the case of the invention described in claim 1, it can be manufactured at a lower cost than a structure having both side rollers. That is, when the cage is provided with both side rollers, it is necessary to strictly regulate the gap between the rolling surface of each cylindrical roller and each pocket, so that high machining accuracy is required. This increases the manufacturing cost of the cage. On the other hand, when the cage is provided with one-sided rollers, high manufacturing accuracy is not required as compared with the structure in which both-sided rollers are provided, so that the manufacturing cost can be reduced. Therefore, according to the first aspect of the present invention, a structure in which a recessed portion due to wear is unlikely to be formed at the outer peripheral side peripheral portion of each pocket can be obtained at a low cost.

  In the case of the invention described in claim 1, only the displacement of the cage toward the one end side in the axial direction is provided with a roller, but conversely, the displacement of the cage at the other end side in the axial direction is provided with a roller. It is also conceivable to provide a race with displacement toward one end in the axial direction. Even in such a configuration, the gap between each pocket and the rolling surface of each cylindrical roller is increased, and an oil film is easily formed on the rolling surface of each cylindrical roller. However, if the cage is displaced to one end in the axial direction until it comes into contact with the race surface, the area of the rubbing portion between the axial end surface of each cylindrical roller and the outer peripheral side peripheral portion of each pocket becomes large, and rubbing occurs. The mating speed V increases. When the cylindrical rollers are skewed in this state, significant wear is likely to occur due to stress concentration at the sliding portion and an increase in PV value. Therefore, in the case of the invention described in the first aspect, the displacement of the cage toward the one end side in the axial direction is restricted by a roller.

  Further, in the case of the invention described in claim 5, the frictional portion between the outer peripheral side peripheral portion of each of the pockets and the outer peripheral side end surface of each cylindrical roller held in each of these pockets is compared with the conventional one. It can be accommodated within a narrow range, and this rubbing portion can be positioned closer to the central portion of each pocket in the circumferential direction. For this reason, the local stress concentration generated in the rubbing portion due to the one piece contact due to the skew can be alleviated, and the sliding speed V of the rubbing portion can be further reduced. As a result, it is difficult to form the recessed portion 23 due to wear as shown in FIG.

Further, since the difference between the roller drop amount and the radial dimension of the chamfered portion is made smaller than the thickness of the metal plate constituting the cage, the chamfered portion is different from the outer peripheral side peripheral portion of each pocket. By contacting, it is possible to prevent adverse effects on the smooth rotation of the cylindrical rollers, and durability can be improved.
Further, since the axial position of the cage is achieved by the engagement between the locking portions formed in the pockets and the rolling surfaces of the cylindrical rollers, both axial sides of the cage There is no rubbing against the opponent race surface. For this reason, it is possible to prevent the retainer from scraping off the lubricating oil adhering to the race surface and to satisfactorily lubricate the rolling contact portion between the race surface and the rolling surface of each cylindrical roller.

  Furthermore, since oil holes are formed at positions of at least one rim portion of the inner diameter side rim portion and the outer diameter side rim portion so as to align with the pockets, lubrication that can be supplied into the pockets is provided. By increasing the amount of oil, an oil film can be sufficiently formed on the surface of each cylindrical roller held in each of these pockets. In the case of the invention described in claim 5, since the axial displacement of the cage is regulated by the relationship between the radial dimension of the chamfered portion of each cylindrical roller and the plate thickness of the metal plate, the axial direction of this cage The displacement amount is smaller than that of a structure in which both side rollers are simply provided, and the gaps between the pockets and the rolling surfaces of the cylindrical rollers may be reduced. In this case, it is difficult for the lubricating oil to enter the pockets, and there is a possibility that the oil film is not sufficiently formed on the surfaces of the cylindrical rollers. On the other hand, by forming the oil holes, a sufficient amount of lubricating oil can be supplied into the pockets, and an oil film can be sufficiently formed on the surfaces of the cylindrical rollers. As a result, the wear at the rubbing portion between the outer diameter side peripheral portion of each pocket and the outer diameter side end surface of each cylindrical roller is suppressed, and the outer diameter side peripheral portion is shown in FIG. It is possible to more effectively prevent the formation of the recessed portion due to wear.

Preferably, when carrying out the invention described in claim 1, as described in claim 2, each cylindrical roller is placed on at least the outer diameter side end surface of the cage of each axial end surface. It is assumed that a central flat surface extending in a direction perpendicular to the rotation center axis and a chamfered portion that continues the outer peripheral edge and the rolling surface of the central flat surface over the entire circumference are provided.
Then, in the state where the cage is displaced to one end side in the axial direction and the outer diameter side locking portions and the inner diameter side locking portions are engaged with the rolling surfaces of the cylindrical rollers, The amount of a part of the cylindrical roller protruding from the outer surface of the outer diameter side flat plate portion (roller protrusion amount) is less than the dimension of the chamfered portion in the radial direction of each cylindrical roller.
At the same time, the width dimension of the chamfered portion in the radial direction of each cylindrical roller is made smaller than the thickness of the metal plate constituting the cage.

If constituted in this way, the friction part between the outer diameter side peripheral portion of each pocket and the outer diameter side end surface of each cylindrical roller held in each pocket is stored in a narrow range compared to the conventional case, This rubbing portion can be positioned at a portion closer to the center in the circumferential direction of each pocket. For this reason, local stress concentration occurring in the rubbing portion is less likely to occur due to a piece contact due to skew, and the sliding speed V of the rubbing portion can be kept small. As a result, it is possible to more effectively prevent the recessed portion due to wear as shown in FIG. 10 described above from being formed in the outer peripheral edge portion.
Furthermore, since the width dimension in the radial direction of the chamfered portion is smaller than the plate thickness of the metal plate constituting the cage, the chamfered portion comes into contact with the outer peripheral side peripheral portion of each pocket, An adverse effect on the smooth rotation of each cylindrical roller can be prevented, and durability can be improved.

Preferably, as described in claim 3, each of the pair of members is rotated when in use, and of these two members, it is present on one end side in the axial direction of the cage and faces the central flat plate portion. The present invention is applied to a structure in which the other member to be used has a faster rotation speed than the other member.
If comprised in this way, even if the said holder | retainer displaces to the member side which rotates at high speed, a clearance gap can always be ensured between the race surface of this member rotating at high speed, and this holder | retainer. For this reason, the lubricating oil can easily enter between the member on the high-speed rotation side and the cage, the lubricity of the race surface can be maintained over a long period of time, and durability and seizure resistance can be improved.

More preferably, as described in claim 4, at least part of at least one of the inner diameter side rim portion and the outer diameter side rim portion constituting the cage is aligned with each pocket in the circumferential direction. Oil holes that penetrate the rim portion in the radial direction of the retainer are formed at the positions where they are to be formed.
If comprised in this way, the quantity of the lubricating oil which can be supplied in each pocket can be increased, and an oil film can fully be formed in the surface of each cylindrical roller hold | maintained in these each pocket. As a result, it was possible to suppress wear at the rubbed portion between the outer peripheral side edge of each pocket and the outer diameter side end surface of each cylindrical roller, and the outer peripheral side peripheral part shown in FIG. It is possible to more effectively prevent the formation of the recessed portion due to wear.

When the invention described in claim 4 or 5 is carried out, preferably, as described in claim 6, each oil hole is formed at least in the inner diameter side rim portion.
If comprised in this way, it is the structure which supplies lubricating oil from the internal diameter side of a thrust cylindrical roller bearing, and it is easy to supply sufficient quantity of lubricating oil in each pocket using a centrifugal force for the transfer of this lubricating oil. .
More preferably, oil holes are formed in both the inner diameter side rim portion and the outer diameter side rim portion.
If comprised in this way, it will become easier to increase the flow volume of the lubricating oil which can be supplied in each pocket.

Moreover, when each invention described in the second to sixth aspects described above is carried out, preferably, as described in the seventh aspect, the surface roughness of the central flat surface of each cylindrical roller is 0 in terms of arithmetic average roughness. The surface roughness of the outer peripheral side peripheral portion of each pocket is 2.51 μm or less in terms of arithmetic average roughness.
If comprised in this way, it will become easy to form an oil film in the contact part of the center flat surface of each cylindrical roller and the outer peripheral side peripheral part of each pocket, and the amount of wear of these each contact part can be reduced. As a result, the cylindrical rollers can be more effectively prevented from entering the cage.

  1 and 2 show a first embodiment of the present invention corresponding to claims 1 to 3. The feature of this embodiment is that the retainer 2a is provided with a one-side roller, and the radial dimension (or center) of the chamfered portion 11 formed in the portion near the outer diameter of each axial end surface of each cylindrical roller 8,8. In relation to the diameter of the central flat surface 9 formed in the part) of the cylindrical rollers 8, 8 in the plurality of pockets 7, 7 provided in the radial direction in the intermediate plate part 6 constituting the retainer 2a. By restricting the movement, even though these cylindrical rollers 8 and 8 are provided with a central flat surface 9 at the center of the axial end surface, the outer peripheral side peripheral edge 22 of each pocket 7 This is to prevent the occurrence of wear that leads to the recess 23 shown in FIG. Since the configuration and operation of the other parts are the same as those of the conventional structure shown in FIGS. 5 to 9, the overlapping illustrations and explanations are omitted or simplified, and the following description will focus on the features of this embodiment. To do.

  In the case of the present embodiment, the thrust cylindrical roller bearing 1a supports a thrust load between the races 25a and 25b (not shown in FIG. 1), which are a pair of members recited in the claims. In the case of the present embodiment, the race 25a existing on one end side in the axial direction (the lower side in FIGS. 1 and 2) has a higher use rotational speed. In the case of the present embodiment, only the displacement of the cage 2a constituting the thrust roller bearing 1a toward the one end in the axial direction is performed between the pockets 7 and 7 and the rolling surfaces 10 of the cylindrical rollers 8 and 8. It is supposed to have a one-side roller that is restricted by engagement. That is, as shown in FIG. 2 (A), the cage 2a causes the axial displacement toward the one end side in the axial direction to be applied to the outer diameter side locking portions 18, 18 and the inner diameter side locking portions 19, 19 respectively. Are engaged with the rolling surface 10 of each cylindrical roller 8 so that a part of each of the cylindrical rollers 8 becomes the leading edge (lower end edge in FIG. 1) of both inner diameter side and outer diameter side rim parts 4 and 5a. The central flat plate portion 13 is restricted so as to remain in a state of protruding in the axial direction.

  Further, as shown in FIG. 2 (B), the cage 2a causes the axial displacement toward the other end in the axial direction (the upper side in FIGS. The outer surface (the upper surface in FIGS. 1 and 2) and the race surface formed on the race 25b on the other end side in the axial direction of the cage 2a of the races 25a and 25b are restricted. For this reason, the front end portion of the folded portion 26 (FIG. 1) of the outer diameter side rim portion 5a is prevented from projecting from the outer surfaces of the outer diameter side and inner diameter side flat plate portions 14 and 15. In the present embodiment, the folded portion 26 is formed, but the folded portion 26 may not be formed as in the conventional structure shown in FIGS. However, if the folded portion 26 is formed, the strength of the outer diameter side rim portion 5a is increased even if the force acting on the outer diameter side rim portion 5a is increased by the centrifugal force acting on each cylindrical roller 8 during operation. Easy to secure.

  In the case of the present embodiment, each cylindrical roller 8 is rolled on each end face in the axial direction with a central flat surface 9 extending in a direction perpendicular to the respective rotation center axes and the outer peripheral edge of the central flat surface 9. It is assumed that a chamfered portion 11 that makes the moving surface 10 continuous over the entire circumference is provided. Further, as shown in FIG. 2A, the cage 2a is displaced toward one end in the axial direction, and the outer diameter side locking portions 18, the inner diameter side locking portions 19 and the cylindrical rollers 8 are moved. In a state where the rolling contact surface 10 is engaged, a part of each of the cylindrical rollers 8 protrudes from the outer surfaces of the outer diameter side and inner diameter side flat plate portions 14 and 15 by δ (roller protrusion amount). I have to. And this protrusion amount (delta) is made less than the width dimension W of the said chamfer part 11 regarding the radial direction of each said cylindrical roller 8 ((delta) <W).

  Therefore, in a state where the outer diameter side and inner diameter side locking portions 18 and 19 are engaged with the rolling surfaces 10 of the cylindrical rollers 8, as shown by a diagonal lattice in FIG. The rubbing surface between the central flat surface 9 of each cylindrical roller 8 and the outer peripheral side peripheral edge portion 22 (FIG. 1) of each pocket 7 falls within the range of the thickness of the metal plate constituting the cage 2a. In other words, the chamfered portion 11 faces the outer surface side portion of the outer diameter side flat plate portion 14 away from the rotation axis of each cylindrical roller 8 in the outer diameter side peripheral edge portion 22, and the outer surface side near the outer surface. A gap exists between the portion and the chamfered portion 11 (no rubbing).

  In this embodiment, the width dimension W of the chamfered portion 11 in the radial direction of each cylindrical roller 8 is made smaller than the thickness T of the metal plate constituting the cage 2a (W <T). Yes. Therefore, even when the retainer 2a is displaced to the other end side in the axial direction and the outer surfaces of both the outer diameter side and inner diameter side flat plate portions 14 and 15 are engaged with the race surface of the race 25b, FIG. As shown by the oblique grid in FIG. 5B, the central flat surface 9 of each cylindrical roller 8 and the outer diameter side peripheral edge portion 22 of each pocket 7 rub against each other. In other words, the inner side surface edge of the outer diameter side peripheral edge portion 22 and the chamfered portion 11 do not rub against each other (contact with the edge).

  As described above, the reason why the width dimension W in the radial direction of the chamfered portion 11 is restricted to be less than the plate thickness T of the metal plate is that in the case of the present embodiment, the retainer 2a is provided with one side roller. 2 (B), the cage 2a is displaced to the other end in the axial direction under actual use conditions, and the outer surfaces of the outer diameter side and inner diameter side flat plate portions 14 and 15 and the race. This is because when the race surface 25b is engaged, the roller fall amount becomes zero. That is, as in the conventional structure shown in FIGS. 5 to 9 described above, the cage 2 can be displaced to the other end side in the axial direction until each pocket 7 and the rolling surface 10 of each cylindrical roller 2 are engaged. When a part of each cylindrical roller 8 remains protruding from the outer surface of both the outer diameter side and inner diameter side flat plate portions 14 and 15 {see (B) of FIGS. 7 and 9}, this protruding amount is the roller falling amount. Become. On the other hand, in the case of the present embodiment, the cage 2a can be displaced to the other axial end side until it engages with the race surface of the race 25b. Therefore, when the cage 2a is displaced to the other end side in the axial direction until the cage 2a engages with the race surface under actual use conditions, a part of each cylindrical roller 8 is both the outer diameter side and inner diameter side flat plate portions 14. , 15 does not protrude from the outer surface, so the amount of roller fall is zero. For this reason, in the case of the present embodiment, only the width dimension W of the chamfered portion 11 is taken into consideration, and the restriction is made in relation to the thickness T of the metal plate constituting the cage 2a.

  Further, in this embodiment, the surface roughness of the central flat surface 9 of each cylindrical roller 8 is 0.32 μm or less, preferably 0.3 μm or less in arithmetic mean roughness (Ra), and each pocket 7a. The surface roughness of the outer diameter side peripheral edge portion 22 is 2.51 μm or less, preferably 2.5 μm or less in terms of arithmetic average roughness (Ra).

  According to the embodiment configured as described above, the wear of the outer peripheral side peripheral edge portion 22 of each pocket 7 provided in the cage 2a is suppressed, and the outer diameter side end portion of each cylindrical roller 8 based on this wear is The thrust cylindrical roller bearing 1a that can prevent the cage 2a from entering one side of the outer diameter portion of the cage 2a can be realized at low cost. That is, in the present embodiment, since the cage 2a is provided with one-side rollers, skew is more likely to occur as compared with the structure shown in FIGS. However, as the displacement of the other axial end side of the cage 2a is provided with a race, the circumference of the rolling surface 10 of each cylindrical roller 8 and the central flat plate portion 13 constituting each pocket 7 is as follows. The gap between the central locking portions 20 and 20 formed at the direction edge can be made larger than that of the structure having the both side rollers. In addition, the oil film on the rolling surface 10 of each cylindrical roller 8 can be easily held (not easily scraped off) by the amount that the gap can be increased in this way. For this reason, even if the effect of suppressing the skew is not sufficient, it is easy to form an oil film on the surface of each cylindrical roller 8, and the outer peripheral side peripheral portion 22 of each pocket 7 is formed as shown in FIG. Moreover, it becomes difficult to form the recessed portion 23 due to wear. And it can prevent that each said cylindrical roller 8 sinks into the said holder | retainer 2a.

  Further, in the case of the present embodiment, it can be manufactured at a lower cost than the structure having the both-side rollers shown in FIGS. That is, when the cage is provided with both side rollers, it is necessary to strictly regulate the gap between the rolling surface 10 of each cylindrical roller 8 and each locking portion 18 to 20 constituting each pocket 7. Processing accuracy is required. For this reason, the manufacturing cost of a cage | basket becomes high. On the other hand, when the cage 2a is provided with one-side rollers as in this embodiment, a high processing accuracy is not required as compared with a structure in which both-side rollers are provided, and thus the manufacturing cost can be reduced. Specifically, high machining accuracy is not required for the central locking portions 20 and 20 of the central flat plate portion 13. Therefore, in the case of the present embodiment, a structure in which a recessed portion due to wear is difficult to be formed in the outer peripheral side peripheral edge portion 22 of each pocket 7 can be obtained at a low cost.

  In the case of this embodiment, only the displacement of the cage 2a toward one end in the axial direction is provided with a roller, but conversely, only the displacement of the cage 2a toward the other end in the axial direction is provided with a roller. It is also conceivable to provide a race with displacement toward one end side in the axial direction. Even in such a configuration, the clearance between the outer diameter side and inner diameter side engaging portions 18 and 19 constituting each pocket 7 and the rolling surface 10 of each cylindrical roller 8 is increased, and each of these cylindrical rollers It becomes easy to form an oil film on the eight rolling contact surfaces 10. However, when the cage 2a is displaced to one end side in the axial direction until it comes into contact with the race surface, the central flat surface 9 formed on the end surface in the axial direction of each cylindrical roller 8 and the outer peripheral side peripheral portion of each pocket 7 The area of the rubbing portion with 22 increases, and the rubbing speed V at the rubbing portion increases at the outer portion in the radial direction of each cylindrical roller 8. In addition, if the cylindrical rollers 8 are skewed in this state, significant wear is likely to occur due to stress concentration at the rubbing portion and an increase in PV value. Further, the roller protrusion amount δ is set to be less than the width dimension W of the chamfered portion 11 of each cylindrical roller 8, and the width dimension W of the chamfered portion 11 is set to the plate thickness T of the metal plate constituting the cage 2a. It becomes difficult to adopt a structure of less than. That is, it is necessary to increase the width dimension of the chamfered portion 11 as the amount of displacement toward the one end side in the axial direction increases, and in order to make the width dimension of the chamfered portion 11 smaller than the plate thickness of the metal plate, It is necessary to increase the thickness of the metal plate. Increasing the thickness of the metal plate is not preferable in terms of weight increase and processing difficulty. Therefore, in the case of the present embodiment, the displacement of the retainer 2a toward one end side in the axial direction (not the other end side in the axial direction) is restricted by a roller.

  Further, in the case of this embodiment, the race 25a existing on the roller holding side (in the case of this embodiment, the lower side in FIG. 2) is a member that rotates at a high speed. As described above, even when the cage 2a is displaced toward the race 25a, the race surface of the race 25a rotating at high speed and the outer surface (the lower surface in FIG. 2) of the central flat plate portion 13 constituting the cage 2a. A gap can always be secured between them. For this reason, it is possible to prevent the lubricating oil from easily entering between the race 25a and the cage 2a, and to prevent the amount of the lubricating oil present on the surface of the race 25a from being applied due to a large centrifugal force based on the high speed rotation. Further, the lubricity of the race surface of the race 25a can be maintained over a long period of time, and durability and seizure resistance can be improved. On the other hand, as shown in FIG. 2B, when the cage 2a tends to be displaced toward the race 25b, both the outer diameter side and inner diameter side flat plate portions 14 constituting the cage 2a. , 15 and the race surface of the race 25b are in contact with each other, or the gap between the two surfaces is reduced. For this reason, it becomes difficult for lubricating oil to enter between the race 25b and the cage 2a. However, the rotational speed of the race 25b is slow, and the centrifugal force that tries to shake off the lubricant that adheres to the surface of the race 25b is small. It can be suppressed.

  Further, in the case of this embodiment, by restricting the relationship between the roller protrusion amount δ and the width dimension W of the chamfered portion 11 as described above (δ <W), the outer peripheral side peripheral portion of each pocket 7 is set. 22 and the rubbing portion between the central flat surface 24 of the outer diameter side end surfaces of the cylindrical rollers 8 held in the pockets 7 are accommodated within a narrow range, and the rubbing portions are further accommodated in the pockets 7. It can be located in the central part of the circumferential direction. For this reason, even if a skew occurs, local stress concentration is unlikely to occur in the rubbing portion due to a piece contact due to the skew. Furthermore, the sliding speed of the rubbing portion can be kept small. As a result, it is possible to more effectively suppress the formation of the recessed portion 23 due to wear as shown in FIG. And it can prevent that each said cylindrical roller 8 sunk inside the said holder | retainer 2a. In the case of the present embodiment, the width dimension W of the chamfered portion 11 is smaller than the plate thickness T of the metal plate constituting the cage 2a (W <T). By contacting the outer diameter side peripheral edge portion 22 of each pocket 7, it is possible to prevent adverse effects on the smooth rotation of each cylindrical roller 8, and durability can be improved.

  In the case of this embodiment, the surface roughness of the central flat surface 9 of each cylindrical roller 8 is 0.32 μm or less (preferably 0 or 3 μm or less) in terms of arithmetic average roughness (Ra). The surface roughness of the outer peripheral side edge of the pocket 7 is set to 2.51 μm or less (preferably 2.5 μm or less) in terms of arithmetic average roughness (Ra). If comprised in this way, it will become easy to form an oil film in the contact part of the center flat surface 9 of each said cylindrical roller 8, and the said outer peripheral side peripheral part 22, and the amount of wear of these each contact part can be reduced. As a result, it is possible to more effectively prevent the cylindrical rollers 8 from entering the cage 2a.

Table 1 below shows the results of experiments conducted to confirm the effects of this example. In the experiment, a thrust cylindrical roller bearing having a pitch circle diameter (PCD) of 62 mm for each roller was operated at a rotational speed of 18000 min ⁻¹ for 20 hours, and then a large amount of the outer peripheral edge of each pocket of the cage was worn. The amount of wear (mm) at the outer peripheral edge was measured. In the experiment, three types of surface roughness Ra, 0.71 μm, 0.32 μm, and 0.16 μm of the central flat surface of the outer diameter side end surface are prepared for each cylindrical roller. The surface roughness of the diameter side peripheral portion was Ra, 3.64 μm, 2.51 μm, and 1.68 μm were prepared, and each was performed in combination. Further, various dimensional relationships between the cage and each cylindrical roller satisfy the conditions of this embodiment described above except for the central flat surface of each cylindrical roller and the surface roughness of the outer peripheral edge.

  As is apparent from Table 1, the wear amount of the outer peripheral side edge portion shows a good result in the whole range. In particular, the surface roughness of the central flat surface of the cylindrical roller is 0.32 μm in Ra. Hereinafter, better results are shown when the surface roughness of the outer peripheral edge is 2.51 μm or less. Therefore, if the various conditions of the present embodiment are satisfied and the surface roughness of the central flat surface and the outer diameter side peripheral edge is restricted, the wear amount of the outer diameter peripheral edge can be sufficiently suppressed, It can be seen that the cylindrical roller can be more effectively prevented from entering the cage.

  Although not shown in the drawings, as described in claim 4, each of the inner diameter side rim portion 4 and the outer diameter side rim portion 5a constituting the retainer 2a is arranged in the circumferential direction of at least one rim portion. You may form the oil hole which penetrates this rim | limb part to the radial direction of the said holder | retainer 2a in the position aligned with the pocket 7, respectively. With this configuration, the amount of lubricating oil that can be supplied into the pockets 7 can be increased, and an oil film can be sufficiently formed on the surfaces of the cylindrical rollers 8 held in the pockets 7. As a result, the wear at the rubbing portion between the outer peripheral side peripheral portion 22 of each pocket 7 and the central flat surface 9 of each cylindrical roller 8 is suppressed, and the outer peripheral side peripheral portion 22 has the above-described figure. As shown in FIG. 10, the formation of the recessed portion 23 due to wear can be more effectively prevented.

  The oil holes are preferably formed at least in the inner diameter side rim portion 4 as described in claim 6. With this configuration, the lubricating oil is supplied from the inner diameter side of the thrust cylindrical roller bearing 1a, and the centrifugal force generated by the rotation of the cage 2a is utilized for the transfer of the lubricating oil, so that each pocket 7 It is easy to supply a sufficient amount of lubricating oil. Furthermore, it is more preferable to form the oil holes in both the inner diameter side rim portion 4 and the outer diameter side rim portion 5a. If comprised in this way, it will become easier to increase the flow volume of the lubricating oil which can be supplied in the said each pocket 7. FIG.

  3 to 4 show a second embodiment of the present invention corresponding to claims 5 and 6. In this embodiment, both side rollers are provided to restrict the axial position of the cage 2b by engaging the circumferential edges of the pockets 7 and 7 with the rolling surfaces 10 of the cylindrical rollers 8 and 8. Adopted a structure. And in relation to the width dimension (or the diameter of the central flat surface 9 formed in the central portion) in the radial direction of the chamfered portion 11 formed in the portion closer to the outer diameter of each axial end surface of each cylindrical roller 8, 8 The movement of the cylindrical rollers 8 and 8 in the plurality of pockets 7 and 7 provided in the radial direction in the intermediate plate portion 6 constituting the cage 2b is restricted, and the pockets 7 are formed in the outer rim side rim portion 5b. Even if the cylindrical roller 8 having the central flat surface 9 at the center of the axial end face is used as the cylindrical rollers 8 by forming the oil holes 27, 27 communicating with the pockets 7, the pockets 7, 7 The outer diameter side peripheral edge portion 22 is prevented from being worn such that it is connected to the recessed portion 23 shown in FIG. Since the configuration and operation of the other parts are the same as those of the conventional structure shown in FIGS. 5 to 9, the overlapping illustrations and explanations are omitted or simplified, and the following description will focus on the features of this embodiment. To do.

In the case of the present embodiment, as shown in FIG. 4A, the cage 2b is displaced toward one end side in the axial direction (the lower side in FIGS. In a state where the side locking portions 18 and 18 and the inner diameter side locking portions 19 and 19 are engaged with the rolling surfaces 10 of the cylindrical rollers 8, a part of the cylindrical rollers 8 is part of the cage 2b. The amount of protrusion (roller protrusion amount) δ ₁ protruding from the outer surface of both the outer diameter side and inner diameter side flat plate portions 14 and 15 constituting the diameter is less than the dimension W of the chamfered portion 11 in the radial direction of each cylindrical roller 8 (δ ₁ < W). Accordingly, in a state where the outer diameter side and inner diameter side locking portions 18 and 19 are engaged with the rolling surfaces 10 of the cylindrical rollers 8, as shown by a diagonal lattice in FIG. The friction surface between the central flat surface 9 of each cylindrical roller 8 and the outer peripheral side peripheral edge portion 22 (FIG. 3) of each pocket 7 is within the range of the thickness of the metal plate constituting the cage 2b. . In other words, the chamfered portion 11 is opposed to a portion near the surface of the outer diameter side flat plate portion 14 away from the rotation axis of each cylindrical roller 8 in the outer diameter side peripheral edge portion 22 of each pocket 7. A gap exists between these portions close to the surface and the chamfered portion 11 (no rubbing).

Further, in this embodiment, as shown in FIG. 4B, the cage 2b is displaced to the other end side in the axial direction (upper side in FIGS. 3 and 4) with respect to each cylindrical roller 8. In a state where the central locking portions 20 and 20 are engaged with the rolling surfaces 10 of the cylindrical rollers 8, a part of each of the cylindrical rollers 8 is fixed to the outer diameter side and inner diameter side flat plate portions 14, 15 is projected from the outer surface by δ ₂ minutes (roller drop amount). Then, the difference (W−δ ₂ ) between the protrusion amount δ ₂ and the width dimension W of the chamfered portion 11 in the radial direction of each cylindrical roller 8 is determined from the thickness T of the metal plate constituting the cage 2b. Is also small {(W−δ ₂ ) <T}. Therefore, even when the central locking portions 20 and 20 and the rolling surfaces 10 of the cylindrical rollers 8 are engaged with each other, as shown in FIG. The central flat surface 9 and the outer diameter side peripheral edge 22 of each pocket 7 rub against each other. In other words, the inner surface side edge of the outer diameter side peripheral edge portion 22 and the chamfered portion 11 do not rub against each other (contact with the edge).

  In the case of the present embodiment, the outer diameter side rim portion 5b penetrates the outer diameter side rim portion 5b in the radial direction of the cage 2b at a position aligned with the pockets 7 in the circumferential direction. Oil holes 27 are formed. That is, in the case of the present embodiment, the outer diameter side rim portion 5b is composed of a cylindrical portion 28 that is continuous with the intermediate plate portion 6 and a folded portion 26 that is folded back 180 ° from the tip of the cylindrical portion 28. The tip of the folded portion 26 does not protrude from the outer surfaces of the outer diameter side and inner diameter side flat plate portions 14 and 15. In the case of the present embodiment, the cylindrical portion 28 and the folded portion 26 pass through the cylindrical portion 28 and the folded portion 26 in the radial direction of the cage 2b in the intermediate portion with respect to the axial direction of the cage 2b. Each oil hole 27, 27 is formed. The positions where these oil holes 27 are formed are aligned with the pockets 7 in the circumferential direction of the cage 2a. Therefore, in a state where the cylindrical rollers 8 are disposed in the pockets 7, the outer diameter side end surfaces 21 of the cylindrical rollers 8 and the oil holes 27, 27 face each other. In the case of the cage 2b of the present embodiment, the folded portion 26 is formed. However, the folded portion 26 may not be formed as in the conventional structure shown in FIGS. However, if the folded portion 26 is formed, the strength of the outer rim side rim portion 5b is increased even if the force acting on the outer rim side rim portion 5b is increased by the centrifugal force acting on each cylindrical roller 8 during operation. It becomes easy to secure.

  In the case of the present embodiment, the surface of the outer-diameter side flat plate portion 14 away from the rotation center axis of each cylindrical roller 8 in the outer-diameter side peripheral edge portion 22 of the outer-diameter side peripheral portion 22 {FIG. 4A). Of the cylindrical roller 8 and the central flat surface 9 of each cylindrical roller 8 are prevented from rubbing against each other. In other words, the rubbing portion between the outer peripheral side peripheral portion 22 of each pocket 7 and the central flat surface 9 of each cylindrical roller 8 held in each pocket 7 is shown in FIG. As indicated by the lattice, the pockets 7 are located at the central portions in the circumferential direction. For this reason, local stress concentration is less likely to occur in the rubbing portion due to a piece contact due to skew, and the sliding speed V of the rubbing portion can be kept small. As a result, it is possible to prevent the concave portion 23 due to wear as shown in FIG. 10 from being formed in the outer peripheral side peripheral edge portion 22 portion. Further, the inner edge of the outer peripheral edge 22 and the chamfered portion 11 do not come into contact with each other, and no significant wear occurs in the portion.

In this embodiment, the difference between the roller drop amount δ ₂ and the width dimension W in the radial direction of the chamfered portion 11 is made smaller than the thickness T of the metal plate constituting the cage 2b. Since the chamfered portion 11 is in contact with the outer diameter side peripheral edge portion 22 of each pocket 7, it is possible to prevent adverse effects on the smooth rotation of each cylindrical roller 8, and the durability can be improved.

  In the case of this embodiment, the axial position of the cage 2 b is related to the locking portions 18 to 20 formed in the pockets 7 and the rolling surfaces 10 of the cylindrical rollers 8. Therefore, the both side surfaces in the axial direction of the cage 2b do not rub against each other race surface. For this reason, it is possible to prevent the retainer 2b from scraping off the lubricating oil adhering to the race surface, and it is possible to satisfactorily lubricate the rolling contact portion between the race surface and the rolling surface 10 of each cylindrical roller 8. For this reason, it is possible to prevent damage to the rolling surface 10 and the respective race surfaces even under severe use conditions.

  Furthermore, since the oil holes 27 and 27 are formed at positions aligned with the respective pockets 7 of the outer diameter side rim portion 5b, the amount of lubricating oil that can be supplied into these pockets 7 is increased, An oil film can be sufficiently formed on the surface of each cylindrical roller 8 held in each pocket 7. In the case of the present embodiment, the axial displacement of the cage 2b is regulated by the relationship between the radial dimension of the chamfered portion 11 of each cylindrical roller 8 and the plate thickness of the metal plate. As shown in FIGS. 5 to 9, the amount of displacement in the direction is smaller than that of the structure in which the both-side rollers are simply provided, and the gaps between the pockets 7 and the rolling surfaces 10 of the cylindrical rollers 8. May also be smaller. In this case, it is difficult for the lubricating oil to enter the pockets 7 and the oil film may not be sufficiently formed on the surfaces of the cylindrical rollers 8. Therefore, by forming the oil holes 27, 27, a sufficient amount of lubricating oil can be supplied into the pockets 7, and an oil film can be sufficiently formed on the surface of the cylindrical rollers 8. As a result, it is possible to suppress wear at the rubbing portion between the outer peripheral side peripheral portion 22 of each pocket 7 and the central flat surface 9 of each cylindrical roller 8. As shown in FIG. 10, the formation of the recessed portion 23 due to wear can be more effectively prevented.

  The oil holes 27, 27 may be formed not in the outer diameter side rim portion 5 b but in the inner diameter side rim portion 4 as described in claim 6. With this configuration, the lubricating oil is supplied from the inner diameter side of the thrust cylindrical roller bearing 1b, and the centrifugal force generated by the rotation of the cage 2b is utilized for the transfer of the lubricating oil, so that each pocket 7 It is easy to supply a sufficient amount of lubricating oil. Further, if the oil holes 27 are formed in both the inner diameter side rim portion 4 and the outer diameter side rim portion 5b, the flow rate of the lubricating oil that can be supplied into each pocket 7 can be increased more easily.

  Also in this embodiment, as described in claim 7, the surface roughness of the central flat surface 9 of each cylindrical roller 8 is 0.32 μm or less (preferably 0.3 μm or less) in terms of arithmetic average roughness. In addition, the surface roughness of the outer peripheral edge 22 of each pocket 7 is preferably 2.51 μm or less (preferably 2.5 μm or less) in terms of arithmetic average roughness. If comprised in this way, it will become easy to form an oil film in the contact part of the center flat surface 9 of each said cylindrical roller 8, and the outer peripheral side peripheral part 22 of each said pocket 7, and the amount of wear of these each contact part will be reduced. Can be reduced. As a result, it is possible to more effectively prevent the cylindrical rollers 8 from entering the cage 2b.

Sectional drawing which shows Example 1 of this invention. In order to explain Example 1 of the present invention, (A) shows a state in which the cage is displaced toward one end in the axial direction with respect to the cylindrical roller, and (B) shows the other end in the axial direction with respect to the cylindrical roller. The figure corresponded in the Ei cross section of FIG. 1 which each shows the state displaced to the side. Sectional drawing which shows Example 2 of this invention. In order to explain Example 2 of the present invention, (A) shows a state in which the cage is displaced toward one end in the axial direction with respect to the cylindrical roller, and (B) shows the other end in the axial direction with respect to the cylindrical roller. FIG. 4 is a view corresponding to the cross section of FIG. 3, showing a state of being displaced to the side. Sectional drawing which shows an example of a conventional structure. The side view which takes out and shows a cylindrical roller. A thrust cylindrical roller bearing showing a state in which the cage is displaced to one end side in the axial direction shown in (A) and the other end side in the axial direction shown in (B) with respect to the cylindrical roller includes the central axis of the cage. The fragmentary sectional view shown in the state cut | disconnected by the virtual plane. The figure which shows this pocket in the state seen from the central-axis direction of the holder | retainer in order to show the shape of the pocket of a holder | retainer. Sectional drawing similar to FIG. 4 for demonstrating the inconvenience which arises when the dimension of the chamfering part of the axial direction end surface of a cylindrical roller is improper. The figure similar to FIG. 8 which shows the state which the outer peripheral side peripheral part of the pocket of the holder | retainer was worn out.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 1a, 1b Thrust cylindrical roller bearing 2, 2a, 2b Cage 4 Inner diameter side rim part 5, 5a, 5b Outer diameter side rim part 6 Intermediate | middle board part 7 Pocket 8 Cylindrical roller 9 Central flat surface 10 Rolling surface 11 Chamfering Part 12 Column 13 Central flat plate part 14 Outer diameter side flat part 15 Inner diameter side flat part 16 Inner diameter side continuous part 17 Outer diameter side continuous part 18 Outer diameter side locking part 19 Inner diameter side locking part 20 Central locking part 21 Outside Diameter side end face 22 Outer diameter side peripheral edge part 23 Recessed part 25a, 25b Race 26 Folded part 27 Oil hole 28 Cylindrical part

Claims (7)

  A cage that is formed in an annular shape and is provided with a plurality of pockets that are radially arranged at a plurality of locations in the circumferential direction, and a plurality of cylindrical rollers that are rotatably held in the pockets. The retainer is integrally formed by bending a metal plate, and is present on the inner peripheral edge, and is formed on an inner diameter side rim that is continuous over the entire circumference, and an outer peripheral edge. A circular outer diameter side rim portion that is concentric with the inner diameter side rim portion and continuous over the entire circumference, and a cross section that exists between the outer diameter side rim portion and the inner diameter side rim portion. An intermediate plate portion whose shape is bent with respect to the radial direction, and intermittently with respect to the circumferential direction in the intermediate plate portion, each pocket formed in the radial direction is provided between the pockets adjacent to each other in the circumferential direction. A plurality of pillar portions, and the intermediate plate portion is the same in the axial direction at the radially intermediate portion. A central flat plate portion formed in the near portion, an outer diameter side flat plate portion formed in a portion near the other axial end adjacent to the radially inner side of the outer diameter side rim portion, and a radially outer side of the inner diameter side rim portion An inner diameter side flat plate portion formed near the other end in the axial direction adjacent to the inner diameter side flat plate portion, an inner diameter side continuous portion that connects the outer peripheral edge of the inner diameter side flat plate portion and the inner peripheral edge of the central flat plate portion, It consists of an outer diameter side continuous part which makes an outer peripheral edge and the inner peripheral edge of the said outer diameter side flat plate part continue, and between a pair of members which have a race surface and a rolling surface of each said cylindrical roller, respectively. In a thrust cylindrical roller bearing for supporting a thrust load, the axial displacement of the cage toward the one end side in the axial direction is caused by a circle of each column portion at a part of the outer diameter side flat plate portion and the inner diameter side flat plate portion. Each outer diameter side locking portion and each inner diameter side locking portion provided at the circumferential edge and each of the above circles As a result of the engagement with the rolling surfaces of the rollers, a part of each of these cylindrical rollers remains in a state of protruding in the axial direction from the leading edge of the inner diameter side and outer diameter side rim portions and the central flat plate portion. The axial displacement of the cage toward the other axial end is controlled by the outer surface of both the outer diameter side and inner diameter side flat plate portions, and the other axial end side of the cage among the two members. A thrust cylindrical roller bearing that is regulated by engagement with a race surface formed on one member existing in the housing.   Each cylindrical roller has a central flat surface extending in a direction perpendicular to the respective rotation center axis on at least an outer diameter side end surface of the cage in both axial end surfaces, and an outer peripheral edge of the central flat surface and rolling. And a chamfered portion that is continuous over the entire circumference, and the cage is displaced to one end side in the axial direction so that each outer diameter side locking portion, each inner diameter side locking portion, and each of the above The amount of a part of each cylindrical roller protruding from the outer surface of the outer diameter side flat plate portion with the rolling surface of the cylindrical roller engaged is less than the dimension of the chamfered portion in the radial direction of each cylindrical roller. A thrust cylindrical roller bearing characterized in that the width dimension of the chamfered portion in the radial direction of each cylindrical roller is smaller than the thickness of the metal plate constituting the cage.   A pair of members are both rotated when in use, and of these two members, the other member that exists on one end side in the axial direction of the cage and faces the central flat plate portion is used rather than one member. The thrust cylindrical roller bearing according to claim 1, wherein the rotational speed is high.   Among the inner diameter side rim portion and the outer diameter side rim portion constituting the cage, at least a part of the rim portion, the rim portion is arranged at a position aligned with each pocket in the circumferential direction. The thrust cylindrical roller bearing according to any one of claims 1 to 3, wherein an oil hole penetrating in a radial direction is formed.   A cage that is formed in an annular shape and is provided with a plurality of pockets that are radially arranged at a plurality of locations in the circumferential direction, and a plurality of cylindrical rollers that are rotatably held in the pockets. The retainer is integrally formed by bending a metal plate, and is present on the inner peripheral edge, and is formed on an inner diameter side rim that is continuous over the entire circumference, and an outer peripheral edge. A circular outer diameter side rim portion that is concentric with the inner diameter side rim portion and continuous over the entire circumference, and a cross section that exists between the outer diameter side rim portion and the inner diameter side rim portion. An intermediate plate portion whose shape is bent with respect to the radial direction, and intermittently with respect to the circumferential direction in the intermediate plate portion, each pocket formed in the radial direction is provided between the pockets adjacent to each other in the circumferential direction. A plurality of pillar portions, and the intermediate plate portion is the same in the axial direction at the radially intermediate portion. A central flat plate portion formed in the near portion, an outer diameter side flat plate portion formed in a portion near the other axial end adjacent to the radially inner side of the outer diameter side rim portion, and a radially outer side of the inner diameter side rim portion An inner diameter side flat plate portion formed near the other end in the axial direction adjacent to the inner diameter side flat plate portion, an inner diameter side continuous portion that connects the outer peripheral edge of the inner diameter side flat plate portion and the inner peripheral edge of the central flat plate portion, An outer diameter side continuous portion that continues the outer peripheral edge and the inner peripheral edge of the outer diameter side flat plate portion, and the axial displacement of the cage toward the one end side in the axial direction is changed to the outer diameter side flat plate portion and the inner diameter side. By engaging each outer diameter side locking portion and each inner diameter side locking portion provided on the circumferential edge of each column portion with a part of the flat plate portion and the rolling surface of each cylindrical roller, these A part of each cylindrical roller is projected in the axial direction from the leading edge of both the inner diameter side and outer diameter side rim parts and the central flat plate part. And the axial displacement of the cage toward the other end in the axial direction is a part of the central flat plate portion and is provided at the circumferential edge of each column portion. Due to the engagement between the central locking portion and the rolling surface of each cylindrical roller, a part of each cylindrical roller remains protruding in the axial direction from the outer diameter side flat plate portion and the inner diameter side flat plate portion. In the thrust cylindrical roller bearing which is regulated in such a manner, each cylindrical roller has a direction perpendicular to each rotation center axis at least on the outer diameter side end face of the cage among the both axial end faces. And a chamfered portion for continuously connecting the outer peripheral edge of the central flat surface and the rolling surface over the entire circumference, and the cage is displaced toward one end in the axial direction. Each outer diameter side locking portion and each inner diameter side locking portion are engaged with the rolling surface of each cylindrical roller. Thus, the amount by which a part of each cylindrical roller protrudes from the outer surface of the outer diameter side flat plate part is made smaller than the dimension of the chamfered part in the radial direction of each cylindrical roller, and the cage is moved in the other axial end. The amount by which a part of each cylindrical roller protrudes from the outer surface of the outer-diameter side flat plate portion in a state where the central locking portion and the rolling surface of each cylindrical roller are engaged with each other. The difference between the dimension of the chamfered portion in the radial direction of each cylindrical roller is smaller than the plate thickness of the metal plate, and at least of the inner diameter side rim portion and the outer diameter side rim portion. A thrust cylindrical roller bearing characterized in that an oil hole penetrating the rim portion in the radial direction of the cage is formed at a position aligned with the pockets in the circumferential direction of one rim portion.   The thrust cylindrical roller bearing according to claim 4 or 5, wherein each oil hole is formed in at least the inner diameter side rim portion. The surface roughness of the central flat surface of each cylindrical roller is 0.32 μm or less in arithmetic mean roughness, and the surface roughness of the outer diameter side peripheral portion of each pocket is 2.51 μm or less in arithmetic mean roughness. A thrust cylindrical roller bearing according to any one of claims 2 to 6.

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