JP2008256162A - Thrust roller bearing - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a thrust roller bearing capable of reducing manufacturing cost and enhancing manufacturing efficiency. <P>SOLUTION: In the thrust roller bearing 1 provided with a retainer 8 having a pocket 16 for rotatably holding a plurality of rolling elements 6 between both washers 2, 4, a circular curved surface 22 is formed on a surface facing the rolling surface of the rolling element 6 of the pocket 16 by forming and the curved surface 22 is formed to satisfy a conditional expression; d1, d2<d<d3 (d1, d2 are minimum distances at both sides of washers 2, 4 between curved surfaces 22a, 22b, d3 is the maximum distance between the curved surfaces 22a, 22b and d is the diameter of the rolling element.) A holding margin of the rolling element of the retainer 8 is specified as elastic deformation by which the rolling element can be inserted into the pocket 16 and a sealing member is provided at the outer circumferential side of the retainer 8 from the pocket 16 to form a gap between the retainer 8 and both the washers 2, 4 in a size to prevent a fine foreign substance from entering in a loaded raceway passage from between both the washers 2, 4. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a thrust roller bearing used, for example, in a roll neck of a rolling mill, and in particular, a thrust roller that prevents the rolling elements from falling off and separating and also prevents entry of minute foreign matter into a load raceway on a raceway surface. Related to bearings.

  Conventionally, for example, a thrust roller bearing 1 as shown in FIG. 4 is used in various machine tools such as a rolling mill. FIG. 4 is a view showing a configuration example of a thrust roller bearing 1 used for a roll neck of a rolling mill, (a) is a cross-sectional view showing a partially enlarged configuration of the thrust roller bearing, and (b). FIG. 4 is a cross-sectional view showing the cage partially enlarged, and FIG. 4C is a plan view showing the pockets of the cage partially enlarged. In this configuration example, the thrust roller bearing 1 is a double-type thrust tapered roller bearing using a tapered roller as a rolling element.

Such a thrust roller bearing 1 includes a shaft washer (bearing ring fitted to the shaft) 2, two housing washer (bearing rings fitted to the housing) 4 a and 4 b, a plurality of rolling elements 6, Two cages 8a and 8b are provided.
The shaft washer 2 is formed in an annular shape using carbon steel or the like, for example, and is fixed to a roll neck (not shown) of the rolling mill so as to rotatably support the roll neck. A shaft washer-side raceway surface 10 is formed on the surface of the shaft washer 2 facing the housing washer 4 over the entire circumferential direction of the shaft washer 2.

  Each housing washer 4a, 4b is formed in an annular shape using, for example, bearing steel or the like, similar to the shaft washer 2, and the axial washer 2 and Opposed to each other. A housing washer-side raceway surface 12 is formed on the surface of each housing washer 4a, 4b facing the shaft washer 2 over the entire circumferential direction of the housing washer 4.

The plurality of rolling elements 6 are constituted by tapered rollers formed using bearing steel or the like, and a load raceway 14 formed between the shaft washer side raceway surface 10 and the housing washer side raceway surface 12. It is arranged so that it can roll freely.
The cages 8a and 8b are disposed between the housing washer 4a and 4b and the shaft washer 2, respectively, are formed in an annular shape using low carbon steel or the like, and have a substantially hollow disc shape. It is comprised from the container main body 26 and the cyclic | annular fitting body 28 fitted to the radial direction outer side of the holder main body 26. As shown in FIG.

A plurality of pockets 16 are formed at predetermined intervals along the circumferential direction at the radially outer edge of the cage body 26. Each of the plurality of pockets 16 is formed with an opening in the radial direction outside, and has a shape that allows the rolling element 6 to be inserted into the pocket 16 from these opening portions.
The fitting body 28 is formed with a plurality of through holes penetrating in the radial direction. These through holes are viewed from the radial direction of the cage body 26 in a state in which the fitting body 28 is fitted to the cage body 26. Thus, it overlaps with the mounting hole of the pillar portion 30 formed between the adjacent pockets 16.

  When forming the cage 8, first, the rolling elements 6 are inserted into the pockets 16, and then the fitting body 28 is fitted to the cage body 26. Then, a pin 32 is driven into the pillar portion 30 between the pockets 16 to fasten the cage body 26 and the fitting body 28 to each other, thereby fitting the fitting body 28 into the cage body 26. When the fitting body 28 is fitted to the cage body 26, the cage 8 is formed, and the rolling elements 6 in each pocket 16 are rotatably held in the pocket 16 by the cage body 26 and the fitting body 28. .

  When the formed cages 8a and 8b are arranged between the housing washer 4a and 4b and the shaft washer 2, the thrust roller bearing 1 is formed. When the thrust roller bearing 1 is formed, the plurality of rolling elements 6 are arranged in the load raceway 14 and can roll along the axial raceway side raceway surface 10 and the housing raceway side raceway surface 12. A spacer 34 is arranged between the housing washer 4a and 4b on the outer peripheral side of the cage 8.

  The rolling mill in which such a thrust roller bearing 1 is used is controlled so as to accelerate the rotation speed at the start of rolling and to reduce the rotation speed at the end of rolling. In this case, for example, the rolling element 6 and the column part 30 may collide with each other due to acceleration or deceleration or due to the swing of the cage 8. In particular, the state in which the axial load is applied from the state where the axial load is not applied (the rolling element 6 is rotating while sliding along the shaft washer side raceway surface 10 and the housing washer side raceway surface 12). Since the rotation of the rolling element 6 is suddenly recovered and the number of revolutions rapidly increases, the collision force between the rolling element 6 and the column portion 30 also increases.

  As described above, when the collision between the rolling element 6 and the column portion 30 is repeated, the pin 32 that fastens the cage body 26 and the fitting body 28 may be loosened. If the pin 32 is loosened, the strength of the cage 8 may be reduced. In this case, when the retainer body 26 and the fitting body 28 are fastened, the pin 32 is driven over the fitting body 28 and the column portion 30, but when the pin 32 is loosened, the column portion 30. This is because it becomes a cantilever fixed beam state, and it becomes difficult to stably hold the rolling elements 6 by the cage 8. As a result, the thrust roller bearing 1 makes it difficult to stably support the roll neck of the rolling mill.

  Further, when the cage 8 includes the cage body 26 and the fitting body 28, both members (the cage body 26 and the fitting body) are used in order to fit the cage body 26 and the fitting body 28 with high accuracy. 28), high machining accuracy is required. In this case, labor and time required for processing are required, and the processing apparatus for the processing is also expensive. As a result, there is a possibility that the manufacturing cost of the cage 8 and the thrust roller bearing 1 increases. .

  Furthermore, when the retainer body 26 and the fitting body 28 are fastened by the pins 32, it is necessary to form through holes and mounting holes for driving the pins 32 in the pillar portions 30 and the fitting bodies 28 of the retainer body 26. . When forming such a through hole and a mounting hole, it is necessary to process the cage body 26 and the fitting body 28 together, which takes time and effort required for the processing, and a processing apparatus therefor Need to be prepared separately. As a result, there is a possibility that the manufacturing cost of the cage 8 and the thrust roller bearing 1 will increase.

  In addition, the column portion 30 into which the pin 32 is driven needs to be firmly formed to ensure the strength in order to hold the pin 32 firmly. In this case, if the pillar part 30 is made thick, the number of the pockets 16 will be restrict | limited according to it. If the number of pockets 16 can be increased, the number of rolling elements 6 can be increased accordingly, so that the thrust load capacity of the thrust roller bearing 1 can be increased. However, if the pillar portion 30 is thickened to hold the pins 32, the number of pockets 16 is limited accordingly, and it is difficult to increase the number of pockets 16. For this reason, there is a limit in increasing the thrust load capacity of the thrust roller bearing 1.

  When the thrust roller bearing 1 is assembled, the rolling elements 6 are inserted into the respective pockets 16 of the cage main body 26, and the cage main body 26 and the fitting body 28 are fastened to each other by the pins 32. 2 and the housing washer 4 are assembled and arranged. However, such work is troublesome and cumbersome, and there is a risk that the work time will be prolonged.

Furthermore, in the cage 8 described above, each pocket 16 is cut from the opening side with a cutting tool such as an end mill, for example, and the four corners of the cut pocket 16 have a relatively steep angle. ing. In this case, for example, when the rolling element 6 and the column portion 30 are repeatedly collided during operation of the rolling mill, stress is concentrated at the four corners of each pocket 16 and stress is generated in the cage 8. There is a risk of damage. As a result, it becomes difficult to stably hold the rolling elements 6 by the cage 8, and it may be difficult to stably support the roll neck of the rolling mill with the thrust roller bearing 1. There is.
In order to solve these problems, for example, there are thrust roller bearings described in Patent Documents 1 and 2.

  In the thrust roller bearing described in Patent Document 1, a cage is formed as a single unit, and in this cage, the rolling elements are arranged at predetermined intervals in the circumferential direction between both raceway surfaces, and are rotatable. A plurality of pockets to be held are integrally formed. Further, relief portions that are always in non-contact with the rolling elements are provided at the four corners of each pocket. Each pocket has an opening for inserting the rolling element into the pocket from both sides in the axial direction. At least one opening has a blade portion that holds the rolling element in the pocket protruding toward the pocket. Is provided. In the thrust roller bearing described in Patent Document 1, each pocket is formed by cutting using a milling cutter or the like.

  With the thrust roller bearing having such a configuration, since the cage is configured as a single unit, the strength (for example, rigidity) of the cage can be improved, and each rolling element is stably held at all times. Therefore, for example, it becomes possible to stably support the roll neck of the rolling mill over a long period of time. Also, since the strength of the entire cage does not decrease even if the pillar part is thinned, it is possible to increase the number of pockets and the number of rolling elements by narrowing the pillar part. Therefore, the load capacity of the thrust roller bearing can be increased.

Moreover, since it becomes possible to cut a plurality of pockets easily and in a short time using a milling cutter or the like, it is possible to reduce labor and time required for processing, and the cage and the thrust roller bearing Manufacturing costs can be greatly reduced.
In addition, since the rolling elements are prevented from falling off from the pockets by the blades, the cage is held between the shaft washer and the housing washer while the plural rolling elements are held by the retainer. It can be incorporated. As a result, it is possible to perform the assembling work more easily and in a shorter time than in the prior art.

  Furthermore, since the relief portions that are always in non-contact with the rolling elements are provided at the four corners of each pocket, for example, even if the rolling element collides with the pillars during operation of the rolling mill, It is possible to alleviate the stress concentration at the four corners. For this reason, it becomes possible to hold each rolling element stably, for example, it becomes possible to stably support a member using a thrust roller bearing such as a roll neck of a rolling mill for a long period of time. .

Further, the thrust roller bearing described in Patent Document 2 is filled with a solid lubricant between both washer plates over the entire circumference between the housing washer and the shaft washer. With this solid lubricant, A plurality of rolling elements are coupled to each other.
In the case of the thrust roller bearing having such a configuration, since the solid lubricant is filled in the bearing, the solid lubricant can prevent the rolling elements from dropping and separating. Further, since the sealing member is constituted by the solid lubricant, it is possible to prevent foreign matters such as dust from entering the bearing.

In addition, as a thrust bearing provided with the seal member, for example, there is one described in Patent Document 3.
In the thrust bearing described in Patent Document 3, an inner retaining ring is fixed to the inner peripheral edge of the outer ring, an outer retaining ring is fixed to the outer peripheral edge of the inner ring, and an inner seal ring is provided between the inner retaining ring and the inner ring. An outer seal ring is provided between the outer holding ring and the outer ring, and a labyrinth seal including a gap between the outer ring and the inner ring is provided in series with both the seal rings.
JP 2006-250155 A JP 2002-89568 A JP 7-317780 A

However, in the thrust roller bearing described in Patent Document 1, each pocket of the cage is formed by cutting using a cutting tool such as a milling cutter.
For this reason, compared to the case where pockets are formed by molding, such as rolling, forging, pressing, and injection molding, it takes time to manufacture the cage, so that the manufacturing cost of the cage increases, There is a risk that the production efficiency of the cage may be reduced.

  Further, in the thrust roller bearing described in Patent Document 2, since the seal member is made of a solid lubricant, a larger amount of solid lubrication is required than the amount actually required for lubrication of the thrust roller bearing. There is a possibility that a problem that an agent is required occurs. Moreover, there is a possibility that the problem that the solid lubricant scatters to the outside during the operation of the thrust roller bearing.

Further, in the thrust roller bearing described in Patent Document 3, since the inner ring and the inner seal ring and the outer ring and the outer seal ring slide when the thrust roller bearing is operated, the operability of the thrust roller bearing is improved. There is a possibility that the problem of lowering may occur.
The present invention has been made paying attention to the above-mentioned problems, and provides a thrust roller bearing capable of forming a pocket by molding and forming a seal member without using a solid lubricant. The task is to do.

In order to solve the above-mentioned problem, the invention described in claim 1 of the present invention includes a pair of bearing discs arranged to face each other so as to be relatively rotatable,
A plurality of rolling elements arranged so as to be freely rollable into a load raceway formed between the raceway surfaces of each of the pair of raceways;
And a cage having a plurality of pockets that are configured as a single unit and that rotatably hold the plurality of rolling elements one by one between the pair of washer plates,
The plurality of pockets are thrust roller bearings arranged at predetermined intervals in the circumferential direction of the washer,
On the surface of the pocket that faces the rolling surface of the rolling element, an arcuate curved portion that curves along the rolling surface is formed by molding,
The curved surface portion is a distance between the two curved surface portions facing each other with the rolling element interposed therebetween, and the minimum distances on the respective washer sides are d1 and d2, respectively, and the two facing each other with the rolling element interposed therebetween. When the maximum distance between the two curved surface portions is d3, and the diameter of the rolling element is d, it is formed so as to satisfy the conditional expression d1, d2 <d <d3,
The holding allowance of the rolling element of the cage is the amount of elastic deformation that allows the rolling element to be inserted into the pocket,
A gap between the cage and the pair of washer between the pair of washer and at least on the outer peripheral side of the pocket of the cage is such that a minute foreign matter does not enter the load raceway from the gap. A seal member as a gap is arranged.

According to the present invention, since the arc-shaped curved surface portion formed on the surface of the pocket rolling element facing the rolling surface is formed by molding, compared with the case where the pocket including the curved surface portion is formed by cutting. Thus, the manufacturing time of the cage can be shortened.
Further, according to the present invention, the curved surface portion is a distance between two curved surface portions facing each other with the rolling elements sandwiched therebetween, and the minimum distances on each washer are d1 and d2, respectively. When the maximum distance between the two curved surface portions is d3 and the diameter of the rolling element is d, it is formed so as to satisfy the conditional expression d1, d2 <d <d3. Furthermore, the holding allowance of the rolling element of the cage is the amount of elastic deformation that allows the rolling element to be inserted into the pocket.

  For this reason, it is possible to arrange the rolling elements in the pocket by elastically deforming the holding allowance of the rolling elements of the curved surface portion of the cage, and from the pocket only by the cage configured as a single unit. It is possible to prevent the rolling elements from dropping and separating. The rolling element holding allowance is a portion (d-d1 and d-d2) in which the gap between two curved surface portions facing each other with the rolling element interposed therebetween is narrower than the diameter d of the rolling element.

Further, according to the present invention, a gap between the cage and the pair of washer is provided between the pair of washer and at least on the outer peripheral side from the pocket of the cage, and a minute foreign matter enters the load raceway from the gap. Since the sealing member having a gap as small as possible is arranged, it is possible to suppress the entry of minute foreign matter into the load track.
Next, of the present invention, the invention described in claim 2 is the invention described in claim 1, wherein a surface of the seal member facing the pair of washer is close to the pair of washer. It is characterized by that.

According to the present invention, the surfaces of the seal member facing the pair of washer are close to the pair of washer so that the gap between the cage and the pair of washer is between the pair of washer and the load washer path. Since the gap is small enough to prevent entry of minute foreign matter, the seal member and the pair of washer are not in contact with each other, and the operability of the thrust roller bearing is improved as compared with the case where the seal member and the pair of washer are in contact with each other. Is possible.
The invention according to claim 3 is the invention according to claim 1, wherein the cage is formed of resin,
The seal member is in contact with the pair of washer plates to seal a gap between the cage and the pair of washer plates.

According to the present invention, since the cage is made of resin, it becomes easy to form the pocket by injection molding, and the manufacturing time of the cage is shortened compared to the case where the pocket is formed by cutting. Is possible.
Further, according to the present invention, since the seal member contacts the pair of washer plates and seals the gap between the cage and the pair of washer plates, the seal member and the pair of washer plates are not in contact with each other. In comparison, it is possible to further suppress the entry of minute foreign matter into the load track.

Next, among the present inventions, the invention described in claim 4 is the invention described in any one of claims 1 to 3, wherein the seal member is formed integrally with the retainer. It is characterized by being.
According to the present invention, since the seal member is formed integrally with the cage, the number of parts of the thrust roller bearing can be reduced, and the manufacturing cost of the thrust roller bearing can be reduced. The production efficiency of the thrust roller bearing can be improved.

  According to the present invention, since it becomes possible to reduce the manufacturing time of the cage, it is possible to reduce the manufacturing cost of the thrust roller bearing and to improve the manufacturing efficiency of the thrust roller bearing. Become.

Next, a first embodiment of the present invention will be described with reference to the drawings.
First, the structure of the thrust roller bearing of this embodiment is demonstrated using FIG.1 and FIG.2. In addition, about the same structure as the conventional thrust roller bearing shown in FIG. 4, the same code | symbol is attached | subjected and demonstrated.

FIG. 1 is a cross-sectional view of a thrust roller bearing 1.
As shown in FIG. 1, the thrust roller bearing 1 includes a shaft washer 2, a housing washer 4, a plurality of rolling elements 6, and a cage 8.
The shaft washer 2 is formed in an annular shape using, for example, bearing steel such as bearing steel SUJ2, and is fixed to a roll neck of a rolling mill and rotatably supports a fixed member. . An axial washer-side raceway surface 10 is formed on the surface of the axial washer 2 facing the housing washer 4 over the entire circumferential direction of the axial washer 2.

As with the shaft washer 2, the housing washer 4 is formed in an annular shape using, for example, bearing steel such as bearing steel SUJ2, and is disposed facing the axial washer 2 in the axial direction. A housing washer-side raceway surface 12 is formed on the surface of the housing washer 4 facing the axial washer 2 over the entire circumferential direction of the housing washer 4.
The plurality of rolling elements 6 are constituted by, for example, tapered rollers formed using bearing steel such as bearing steel SUJ2, and the like, between the shaft washer side raceway surface 10 and the housing washer side raceway surface 12. Are arranged so as to roll freely. In the present embodiment, a case where a thrust tapered roller bearing using a tapered roller as a rolling element is used as the thrust roller bearing 1 will be described as an example.

The cage 8 is disposed between the shaft washer 2 and the housing washer 4 and is formed in an annular shape using low carbon steel or the like.
The cage 8 is formed as a single unit and has a plurality of pockets 16.
The plurality of pockets 16 are arranged at predetermined intervals along the circumferential direction of the cage 8, and the plurality of rolling elements 6 can be freely rotated one by one between the shaft washer 2 and the housing washer 4. keeping.

Therefore, when the rolling element 6 is held in each pocket 16 and the cage 8 is disposed between the shaft washer 2 and the housing washer 4, the shaft washer 2 and the housing washer 4 are in contact with the rolling element 6. Thus, they are arranged to face each other so as to be rotatable relative to each other through the rolling.
On the outer peripheral side of the pocket 16 of the cage 8, a surface facing the shaft washer 2 and the housing washer 4 is close to the shaft washer 2 and the housing washer 4, so that the retainer 8 and the shaft washer 2 are located. And the sealing member 18 which narrows the clearance gap with the housing washer 4 is arrange | positioned.

The seal member 18 is attached to the cage 8 by means such as adhesion, and projections projecting from the outer peripheral portion of the cage 8 to the shaft washer 2 and the housing washer 4 are provided. It is formed by the annular member which has.
The gap formed between the shaft washer 2 and the seal member 18 and the gap formed between the housing washer 4 and the seal member 18 are gaps forming a labyrinth seal, that is, the shaft washer 2 and The gap between the housing raceway 4 and the housing raceway 4 is such that fine foreign matters such as particles do not enter the load raceway 14.

2 is a cross-sectional view taken along line II-II in FIG.
As shown in FIG. 2, an arcuate curved surface portion 22 that curves along the rolling surface 20 is formed on the surface of the pocket 16 that faces the rolling surface 20 of the rolling element 6 by molding. . In FIG. 2, for the sake of explanation, of the two curved surface portions 22 facing each other with the rolling element 6 interposed therebetween, the left curved surface portion 22 in the drawing is referred to as a curved surface portion 22 a, and the right curved surface portion 22 in the drawing. Is described as a curved surface portion 22b.

  Each of the curved surface portions 22a and 22b has a minimum distance d1 and d2 between the curved surface portion 22a and the curved surface portion 22b on the shaft washer 2 side and the housing washer 4 side, respectively. Is formed so as to satisfy the conditional expression d1, d2 <d <d3, where d3 is the maximum distance between the two and the diameter of the rolling element 6 is d. In FIG. 2, the minimum distance on the shaft washer 2 side is described as d1, and the minimum distance on the housing washer 4 side is described as d2. Further, in the present embodiment, a case where the minimum distance d1 on the shaft washer 2 side and the minimum distance d2 on the housing washer 4 side are the same length will be described as an example.

  Further, the cage 8 is formed such that the holding allowance of the rolling element is an elastic deformation amount in which the rolling element 6 can be inserted into the pocket 16. Specifically, the rolling element holding margin of the curved surface portion 22 is elastically deformed, and the minimum distance d1 on the shaft washer 2 side and the minimum distance d2 on the housing washer 4 side are greater than or equal to the diameter d of the rolling element 6. It is formed to become. Here, the rolling element holding allowance is a portion (d-d1 and d-d2) in which the gap between the curved surface portion 22a and the curved surface portion 22b is narrower than the diameter d of the rolling element.

Next, functions and effects of the thrust roller bearing 1 having the above-described configuration will be described.
When manufacturing the cage 8, an arcuate curved surface portion 22 that curves along the rolling surface 20 is formed on the surface of each pocket 16 of the cage 8 that faces the rolling surface of the rolling element 6. It is formed by a molding process such as forging.
When the thrust roller bearing 1 is assembled, the rolling elements 6 are inserted into the pockets 16 of the cage 8. Further, the seal member 18 is attached to the outer peripheral side of the cage 8 by means such as adhesion.

At this time, the retainer 8 is elastic so that the holding margin of the rolling element of the curved surface portion 22 is elastically deformed, and the minimum distance d1 on the shaft washer 2 side and the minimum distance d2 on the housing washer 4 side are It is formed so as to be equal to or larger than the diameter d of the rolling element 6.
Therefore, after elastically deforming the rolling element holding allowance of each curved surface portion 22a, 22b and inserting the rolling element 6 in each pocket 16, the rolling element holding allowance of each curved surface portion 22a, 22b is By restoring the elastically deformed state to the original state, the rolling elements 6 can be rotatably held in the pockets 16.

The curved surface portions 22a and 22b have the minimum distances d1 and d2 between the curved surface portion 22a and the curved surface portion 22b on the shaft washer 2 side and the housing washer 4 side, respectively. When the maximum distance to 22b is d3 and the diameter of the rolling element 6 is d, it is formed so as to satisfy the conditional expression d1, d2 <d <d3.
Therefore, after the rolling elements 6 are rotatably held in the pockets 16, the rolling elements 6 can be prevented from dropping and separating from the pockets 16, and the assembling work of the thrust roller bearing 1 can be prevented. It has become easy.

After the rolling elements 6 are rotatably held in the pockets 16, the cage 8 is disposed between the shaft washer 2 and the housing washer 4 to assemble the thrust roller bearing 1. When the thrust roller bearing 1 is assembled, the plurality of rolling elements 6 are arranged in the load raceway 14 and can roll along the axial raceway side raceway surface 10 and the housing raceway side raceway surface 12.
When the thrust roller bearing 1 is operated, each rolling element 6 rolls in the load raceway 14 so that the shaft washer 2 and the housing washer 4 rotate relative to each other.

At this time, since the seal member 18 is arranged on the outer peripheral side of the pocket 16 of the cage 8, particles such as particles from the space between the shaft washer 2 and the housing washer 4 into the load raceway 14. Intrusion of minute foreign matter is suppressed.
Therefore, in the case of the thrust roller bearing 1 of the present embodiment, an arcuate curved surface that curves along the rolling surface 20 on the surface of each pocket 16 of the cage 8 that faces the rolling surface of the rolling element 6. The part 22 is formed by a molding process such as forging.

For this reason, compared with the case where the pocket 16 including the curved surface portion 22 is formed by cutting, the manufacturing time of the cage 8 can be shortened, and the manufacturing cost of the cage 8 can be reduced. At the same time, the manufacturing efficiency of the cage 8 can be improved.
As a result, the manufacturing cost of the thrust roller bearing 1 can be reduced, and the manufacturing efficiency of the thrust roller bearing 1 can be improved.

Further, in the thrust roller bearing 1 of the present embodiment, the holding allowance of the rolling element included in the curved surface portion 22 of the cage 8 is elastically deformed, and the minimum distance d1 on the shaft washer 2 side and the housing washer 4 side Is formed such that the minimum distance d2 is equal to or larger than the diameter d of the rolling element 6.
For this reason, the rolling elements 6 can be rotatably held in the pockets 16, and the rolling elements 6 can be inserted into the pockets 16 and the pockets 16 can be inserted into the pockets 16 only by the cage 8 formed as a single unit. It becomes easy to hold the rolling elements 6 inserted into the pockets 16 in the pockets 16.

As a result, the assembly work of the thrust roller bearing 1 becomes easy, the manufacturing time of the thrust roller bearing 1 can be shortened, and the manufacturing cost of the thrust roller bearing 1 can be reduced.
Further, in the case of the thrust roller bearing 1 of the present embodiment, the curved surface portions 22a and 22b are set to have the minimum distance between the curved surface portion 22a and the curved surface portion 22b on the shaft washer 2 side and the housing washer 4 side, respectively. When d1 and d2, d3 is the maximum distance between the curved surface portion 22a and the curved surface portion 22b, and the diameter of the rolling element 6 is d, it is formed so as to satisfy the conditional expression d1, d2 <d <d3. is doing.

For this reason, after the rolling elements 6 are rotatably held in the pockets 16 only by the single holders 8, it is possible to prevent the rolling elements 6 from dropping and separating from the pockets 16. .
As a result, the assembly work of the thrust roller bearing 1 becomes easy, the manufacturing time of the thrust roller bearing 1 can be shortened, and the manufacturing cost of the thrust roller bearing 1 can be reduced.

Further, in the thrust roller bearing 1 of the present embodiment, since the seal member 18 is disposed on the outer peripheral side of the pocket 16 of the cage 8, a load is applied between the shaft washer 2 and the housing washer 4. Intrusion of minute foreign matters such as particles into the track 14 is suppressed.
For this reason, unlike the thrust roller bearing in which the seal member 18 is made of a solid lubricant, a larger amount of solid lubricant is not required than the amount actually required for lubricating the thrust roller bearing. The manufacturing cost of the thrust roller bearing can be reduced. Further, it is possible to prevent the solid lubricant from being scattered outside during the operation of the thrust roller bearing.

As a result, the operability and durability of the thrust roller bearing 1 can be prevented from being lowered, and the manufacturing cost of the thrust roller bearing 1 can be reduced. Further, it is possible to suppress adverse effects on the outside of the thrust roller bearing 1.
Further, in the thrust roller bearing 1 of the present embodiment, the seal member 18 is formed by an annular member having protrusions protruding to the shaft washer 2 and the housing washer 4, and the shaft of each protrusion is provided. The surfaces facing the washer 2 and the housing washer 4 are close to the axial washer 2 and the housing washer 4, respectively.

As a result, the seal member 18, the shaft washer 2 and the housing washer 4 are not in contact with each other. Therefore, the thrust roller bearing is operated in comparison with the thrust roller bearing in which the seal member, the shaft washer and the housing washer slide. It becomes possible to improve the property.
In the present embodiment, the case where a thrust tapered roller bearing having a tapered roller as a rolling element is used as the thrust roller bearing 1 has been described as an example. However, the present invention is not limited to this. You may apply the thrust roller bearing 1 of a form to the thrust roller bearing which uses a cylindrical roller as a rolling element.

  Further, in the thrust roller bearing 1 of the present embodiment, the case where the minimum distance d1 on the shaft washer 2 side and the minimum distance d2 on the housing washer 4 side are the same length has been described as an example. It is not limited to this. That is, both the minimum distance d1 on the shaft washer 2 side and the minimum distance d2 on the housing washer 4 side may be less than the diameter d of the rolling element 6, and the minimum distance d1 on the shaft washer 2 side. May be larger than the minimum distance d2 on the housing washer 4 side, and the minimum distance d2 on the housing washer 4 side may be larger than the minimum distance d1 on the axial washer 2 side. In this case, at least one of the minimum distance d1 on the shaft washer 2 side and the minimum distance d2 on the housing washer 4 side is elastically deformed by the holding allowance of the rolling elements of the curved surface portion 22 of the cage 8. What is necessary is just to form so that it may become more than the diameter d of the rolling element 6. FIG.

  Furthermore, in the thrust roller bearing 1 of the present embodiment, the seal member 18 is formed by an annular member having protruding portions that project to the shaft washer 2 and the housing washer 4, and this annular member is attached to the cage 8. However, it is not limited to this. That is, the seal member 18 may be formed integrally with the cage 8 by integrally forming the annular member and the cage 8. In this case, the number of parts of the thrust roller bearing 1 can be reduced, the manufacturing cost of the thrust roller bearing 1 can be reduced, and the manufacturing efficiency of the thrust roller bearing 1 can be improved. .

Next, a second embodiment of the present invention will be described.
FIG. 3 is a diagram showing a configuration of the thrust roller bearing 1 of the present embodiment.
As shown in FIG. 3, the configuration of the thrust roller bearing 1 of the present embodiment is the same as that of the first embodiment described above except for the configuration of the cage 8.
That is, the cage 8 provided in the thrust roller bearing 1 of the present embodiment is formed of, for example, a resin such as glass fiber reinforced nylon, and the cage 8 and the cage 8 are disposed on the inner peripheral side and the outer peripheral side of the pocket 16, respectively. It has the protrusion part 24 formed integrally.

Each protrusion 24 protrudes to the shaft washer 2 and the housing washer 4, and is in contact with the shaft washer 2 and the housing washer 4, so that the cage 8, the shaft washer 2, and the housing washer 4 The gap is sealed. That is, each protrusion 24 has a gap formed between the shaft washer 2 and the seal member 18 and a gap formed between the housing washer 4 and the seal member 18. A seal member is formed between the bearing plate 4 and the gap so that minute foreign matters such as particles do not enter the load raceway 14.
Other configurations are the same as those of the first embodiment described above.

Next, functions and effects of the thrust roller bearing having the above-described configuration will be described. In the following description, since the configuration other than the cage 8 is the same as that of the first embodiment described above, the operation of different parts will be mainly described.
When the thrust roller bearing 1 is operated, each rolling element 6 rolls in the load raceway 14 so that the shaft washer 2 and the housing washer 4 rotate relative to each other.

At this time, the cage 8 is made of resin, and the protrusions 24 formed on the inner and outer peripheral sides of the pocket 16 are in contact with the shaft washer 2 and the housing washer 4 for holding. The gap between the device 8 and the shaft washer 2 and the housing washer 4 is sealed.
For this reason, entry of minute foreign matters such as particles into the load raceway 14 from between the shaft washer 2 and the housing washer 4 is suppressed.

Therefore, in the thrust roller bearing 1 of the present embodiment, since the cage 8 is formed of resin, it is easy to form the pocket 16 by injection molding, compared with the case where the pocket 16 is formed by cutting. Thus, the manufacturing time of the cage 8 can be shortened.
As a result, the manufacturing cost of the cage 8 can be reduced, and the manufacturing efficiency of the cage 8 can be improved. Therefore, the manufacturing cost of the thrust roller bearing 1 can be reduced. At the same time, the manufacturing efficiency of the thrust roller bearing 1 can be improved.

Further, in the thrust roller bearing 1 of the present embodiment, the protrusions 24 formed integrally with the cage 8 on the inner peripheral side and the outer peripheral side of the pocket 16 are respectively formed on the shaft washer 2 and the housing washer. 4, the gap between the cage 8, the shaft washer 2 and the housing washer 4 is sealed.
As a result, it is possible to further suppress the entry of minute foreign matter into the load raceway 14 as compared with a thrust roller bearing in which the seal member 18, the shaft washer 2 and the housing washer 4 are not in contact with each other.
Other actions and effects are the same as those of the first embodiment described above.

It is sectional drawing which shows the structure of the thrust roller bearing of 1st embodiment of this invention. It is the II-II sectional view taken on the line of FIG. It is sectional drawing which shows the structure of the thrust roller bearing of 2nd embodiment of this invention. It is a figure which shows the structure of the conventional thrust roller bearing, (a) is sectional drawing which expands partially the structure of a thrust roller bearing, (b) is sectional drawing which expands a part of a cage, (C) is a top view which expands and shows partially each pocket of a holder | retainer.

Explanation of symbols

1 Thrust roller bearing 2 Axis washer (Race ring fitted to shaft)
4 Housing washer (Raceway ring that fits into the housing)
6 Rolling elements 8 Cage 10 Axial washer side raceway 12 Housing washer side raceway 14 Load raceway 16 Pocket 18 Seal member 20 Rolling surface 22 Curved part 24 Projection part 26 Cage body 28 Fitting body 30 Column part 32 Pin 34 spacer

Claims (4)

A pair of bearings disposed opposite to each other so as to be relatively rotatable;
A plurality of rolling elements arranged so as to be freely rollable into a load raceway formed between the raceway surfaces of each of the pair of raceways;
And a cage having a plurality of pockets that are configured as a single unit and that rotatably hold the plurality of rolling elements one by one between the pair of washer plates,
The plurality of pockets are thrust roller bearings arranged at predetermined intervals in the circumferential direction of the washer,
On the surface of the pocket that faces the rolling surface of the rolling element, an arcuate curved portion that curves along the rolling surface is formed by molding,
The curved surface portion is a distance between the two curved surface portions facing each other with the rolling element interposed therebetween, and the minimum distances on the respective washer sides are d1 and d2, respectively, and the two facing each other with the rolling element interposed therebetween. When the maximum distance between the two curved surface portions is d3, and the diameter of the rolling element is d, it is formed so as to satisfy the conditional expression d1, d2 <d <d3,
The holding allowance of the rolling element of the cage is the amount of elastic deformation that allows the rolling element to be inserted into the pocket,
A gap between the cage and the pair of washer between the pair of washer and at least on the outer peripheral side of the pocket of the cage is such that a minute foreign matter does not enter the load raceway from the gap. A thrust roller bearing characterized in that a seal member serving as a gap is arranged.   2. The thrust roller bearing according to claim 1, wherein surfaces of the seal member facing the pair of raceways are close to the pair of raceways. The cage is made of resin,
2. The thrust roller bearing according to claim 1, wherein the seal member is in contact with the pair of washer plates to seal a gap between the cage and the pair of washer plates. The thrust roller bearing according to any one of claims 1 to 3, wherein the seal member is formed integrally with the cage.