JP2011231876A - Cage for thrust roller bearing, and thrust roller bearing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To increase the strength by simplifying a structure of a cage for a thrust roller bearing, and to hold a cylindrical roller.SOLUTION: A cage 6 includes an annular part 7, and a plurality of column parts 8 which are projected inwardly in the radial direction from the annular part 7 and integrated with the annular part 7 with intervals in the circumferential direction. A pocket 9 for accommodating a cylindrical roller is formed of the annular part 7 and the column parts 8, 8 adjacent thereto. A side surface 9a of the pocket 9 is formed into a cylindrical surface capable of holding the cylindrical roller, and a stopper part 14 to be engaged with an end face of the cylindrical roller is provided on a fore end of the pocket 9.

Description

  The present invention relates to a cage used for a high-load thrust roller bearing and a thrust roller bearing incorporating the same.

  As a cage used for a high-load thrust roller bearing used in a reducer of a pulverizer that pulverizes cement raw materials or the like, for example, as disclosed in Patent Document 1, an annular inner ring portion is used. Consists of a cage main body integrally provided with the inner ring portion with a plurality of radially projecting pillar portions, and an annular outer ring body that fits on the outer periphery of each pillar portion, and the tip of each pillar portion of the cage body Some pin holes in the radial direction are provided in the surface and the outer ring body, and the pins are press-fitted into the pin holes so that the cage body and the outer ring body are integrated.

  By integrating the cage main body and the outer ring body, a pocket for accommodating the cylindrical rollers is formed by the inner ring portion, the plurality of column portions, and the outer ring body of the cage main body. When the thrust roller bearing rotates, the end surface of the cylindrical roller to which centrifugal force acts is pressed against the end surface of the pocket, that is, the inner surface of the outer ring body, and rotates.

  However, the above thrust roller bearing retainer is loosened due to the vibration of the retainer caused by the rotation of the bearing or the cylindrical roller being strongly pressed against the inner surface of the outer ring body by centrifugal force. Cause.

  Further, during the rotation of the thrust roller bearing, the axial end surface of the cylindrical roller is in a state where only its outer peripheral edge is in contact with the inner surface of the annular outer ring body, so-called edge contact. In this state, the cylindrical roller is pressed against and slides on the inner surface of the outer ring body, which may cause local wear on the inner surface of the outer ring. For this reason, it is necessary to make the end face shape of a cylindrical roller into a spherical surface, and there exists a problem which the man-hour of a roller increases.

  In addition to the above, as shown in FIG. 10, there is one in which the upper and lower holding members are formed by dividing the cage in the horizontal direction. That is, the upper holding member integrally connects the upper outer ring portion 21a and the upper inner ring portion 22a by the pillar portion 23a. Similarly, the lower holding member posts the lower outer ring portion 21b and the lower inner ring portion 22b to the pillar. The parts 23b are integrally connected, and the cylindrical roller 24 is sandwiched between upper and lower holding members and connected by screws 25 or the like. In such a cage, it is necessary to precisely match the upper and lower holding members, and it takes time for processing, and the fastening may be loosened during use as described above.

  In these cages, at least two members are integrated by fastening means such as screws in order to hold the cylindrical rollers, and there is a problem that the number of parts increases and the assembly man-hour increases.

  On the other hand, there are some which use only the upper holding member of FIG. 10 as a retainer for the cylindrical roller, but there is a problem that the handleability is poor because the cylindrical roller cannot be held at all.

JP 2006-258130 A

  Accordingly, a first object of the present invention is to reduce the number of constituent members of the cylindrical roller cage as much as possible and to hold the cylindrical rollers within a certain range. A second problem of the present invention is to form a cage with a minimum number of members and to hold the cylindrical roller so as not to drop out of the cage. A third object of the present invention is to prevent edge contact with the pocket end surface of the cage even when a cylindrical roller having a normal flat end surface is used.

  In order to solve the first problem, a thrust roller bearing retainer according to the present invention includes an annular portion, and protrudes radially inward from the annular portion so as to be integrated with the annular portion at a circumferential interval. A plurality of pillars provided, and a pocket for accommodating cylindrical rollers is formed by the annular part and the adjacent pillar part, and a cylindrical surface along a circumferential outer periphery of the cylindrical roller is formed on a side surface of the pillar part. By doing so, the cylindrical roller is held so as not to fall off at least in the circumferential direction.

  In order to solve the second problem, in the present invention, a stopper portion for engaging the cylindrical roller is provided at the end portion of the pocket, thereby preventing the cylindrical roller from dropping off from the pocket in the axial direction. .

  In order to solve the third problem, in the present invention, the inner end surface of the pocket, that is, the inner surface of the annular portion is formed flat, and even if an ordinary cylindrical roller having a flat end surface is used, edge contact occurs. I tried not to.

  In the thrust roller bearing retainer, a pair of retainer divided bodies are formed by dividing the annular portion in the circumferential direction at the positions of the two pillar portions opposed in the diameter direction. It is good also as a structure which couple | bonded the slot part mutually and was integrated in cyclic | annular form.

  As a means for connecting both the cage divided bodies, a connecting portion that protrudes in the circumferential direction is formed in the split portion of the both cage divided bodies, and the connecting portion is formed at the tip thereof and protrudes in one axial direction. A radial ridge, and a radial groove provided between the ridge and the slit portion, the connecting portions of the two cage segments are overlapped with each other, and the ridge and the groove It is possible to adopt a configuration in which

  The annular portion and the plurality of pillar portions can be integrally formed by casting. Further, the annular portion and the plurality of column portions may be integrally formed by injection molding.

  The thrust roller bearing according to the present invention is completed by holding the cylindrical roller in the cage as described above and mounting the cage between a pair of washer disks.

  As described above, according to the present invention, a plurality of pillar portions are provided integrally with the annular portion, projecting radially inward from the annular portion and spaced in the circumferential direction, and the outer peripheral surface of the cylindrical roller on the side surface of the pillar portion. Since it can be held, the strength is high with a simple structure, and the cylindrical roller can be prevented from falling off the cage.

  Furthermore, since the end surface of the pocket is a flat surface, the cylindrical roller can be prevented from hitting the edge without special processing, and wear of the annular portion is suppressed.

Sectional drawing which shows the use condition of the cage for thrust roller bearings concerning 1st Embodiment of this invention Side view showing the above thrust roller bearing cage The enlarged plan view which shows the cage for thrust roller bearings same as the above Enlarged perspective view showing the same thrust roller bearing retainer (A) Explanatory drawing which shows the manufacturing method of the retainer for thrust roller bearings same as the above, (b) The longitudinal cross-sectional view which shows the processing state of the workpiece | work with a rotary processing tool, (c) The longitudinal cross-sectional view which shows the state after processing of a workpiece | work Enlarged perspective view showing the roller retaining portion of the same thrust roller bearing retainer The expanded perspective view which shows the other form of a roller retaining part same as the above Plan view showing split cage (A) Exploded perspective view showing the same slot part, (b) Enlarged perspective view showing the coupling state of the same slot part An exploded perspective view showing an example of a conventional cage for a thrust roller bearing

  Hereinafter, a first embodiment of the present invention will be described with reference to the accompanying drawings.

  FIG. 1 shows a thrust roller bearing incorporating a cage. As shown in the figure, this thrust roller bearing includes a pair of washer 1 and washer 2 that are opposed in the axial direction, and a plurality of cylindrical rollers 5 that are rolling elements interposed between the opposed surfaces of both washer 1 and 2. The cage 6 holds the cylindrical rollers 5 at intervals in the circumferential direction.

  The raceways 1 and 2 have raceways 3 and 4 on the inner surface in the axial direction, the raceway 3 and the raceway 4 are arranged so as to face each other, and cylindrical rollers 5 interposed between the facing surfaces follow the raceways 3 and 4. Rolling. The cylindrical roller 5 has end surfaces 5a orthogonal to the central axis on both sides, and the outer peripheral edge of the end surface 5a is chamfered.

This thrust roller bearing is used for a large capacity thrust roller bearing with a large axial load, for example, a reducer of a crusher for crushing cement raw materials, etc., and rotatably supports a shaft (not shown). ing. The cylindrical roller 5 is not limited to a straight cylindrical shape, and includes a convex roller (a barrel roller).

  As shown in FIGS. 2 and 3, the cage 6 that holds the plurality of cylindrical rollers 5 has an annular annular portion 7, and protrudes radially inwardly from the annular portion 7 and is annularly spaced in the circumferential direction. It has a plurality of pillars 8, 8... Integrally provided with the part 7.

  As shown in FIG. 4, the column portion 8 is integrally formed with the same thickness T as the annular portion 7, and the pocket 9 is circumferentially formed by the inner surface of the annular portion 7 and the side surface of the adjacent column portion 8. The cylindrical rollers 5 are accommodated in the pockets 9 so as to be able to roll.

As shown in FIG. 4, the side surface 9 a of the pocket 9 (opposite surface of the adjacent column portion 8) is formed on a cylindrical surface along the outer peripheral surface of the cylindrical roller 5 to be accommodated, and prevents the cylindrical roller 5 from coming off in the radial direction. is doing. Therefore, the thickness T is set to a range sufficient to form such a cylindrical surface and the outer peripheral surface of the cylindrical roller 5 can be in contact with the tracks 3 and 4. Further, the end surface 9 b of the pocket 9 (the inner surface of the annular portion 7) is formed as a flat surface orthogonal to the central axis of the side surface 9 a facing the pocket 9.

  In addition, what is necessary is just to form the side surface 9a of the pocket 9 in the curved surface which follows the outer peripheral surface of the convex roller, for example, when a cylindrical roller is a convex roller.

  Further, if the end surface 9b of the pocket 9 is formed to be a flat surface, even if the end surface 5a of the cylindrical roller 5 that is in contact with the end surface 9b is a flat surface (see FIG. 3), the edge contact does not occur. It is not necessary to form the end surface of the roller 5 into a spherical surface.

A method for manufacturing the cage 6 is as follows.
First, an annular work 11 made of metal is manufactured. The work 11 is manufactured in an annular shape having an axial cross section (cross section in a plane passing through the central axis of the work 11) in the annular portion 7 and the column portion 8 of the cage 6 over the entire circumference.

  Next, on the inner peripheral portion of the work 11, a rotary processing tool 12 having a cylindrical shape having the same diameter as the cylindrical roller 5 and having a processing portion on its end surface 12a is moved radially outward while rotating (FIG. 5). (See (a)). This movement is performed in a state where the rotation axis 13 provided on the center axis of the rotary machining tool 12 is aligned with the center axis of the cylindrical roller 5 accommodated in the pocket 9.

  Subsequently, the rotary processing tool 12 is further moved radially outward (see FIG. 5B), and the radial movement is stopped at a position where the cylindrical roller 5 can be accommodated. Thereafter, the rotary machining tool 12 is extracted from the workpiece 11 to form a pocket 9 (see FIG. 5C).

The rotary processing tool 12 has a cylindrical shape, and an end surface 12a is formed on a flat surface orthogonal to the central axis, and the end surface 12a includes a processing portion. For this reason, the side surface 9 a of the pocket 9 is formed on a cylindrical surface along the outer peripheral surface of the cylindrical roller 5, and the end surface 9 b of the pocket 9 is formed on a flat surface facing the end surface 5 a on the radially outer side of the cylindrical roller 5. .

As the rotary processing tool 12, for example, a milling cutter, an end mill, or a grindstone for grinding or polishing can be applied. Further, a roller having a slightly larger diameter than the outer diameter of the cylindrical roller 5 may be used. In this case, the rotary machining tool 12 is set to an outer diameter that can prevent the cylindrical roller 5 from coming off in the radial direction by the side surface 9 a of the pocket 9.

  By performing the above-described series of processes for the circumferentially equal intervals of the workpiece 11, the cage 6 in which the pockets 9 are formed at equal circumferential intervals can be manufactured. In the cage 6, a plurality of column portions 8 are integrally provided on the annular portion 7, and each column portion 8 is formed with the same thickness T as the thickness of the annular portion 7, and the strength of the cage 6 is ensured. it can.

  Further, the end surface 9 b of the pocket 9 can be formed in a flat surface, and the end surface 9 b of the pocket 9 can be opposed to the end surface 5 a on the radially outer side of the cylindrical roller 5.

  For example, in the case where the annular portion 7 and the column portion 8 of the cage 6 are made of metal, the annular portion 7 and the column portion 8 can be manufactured by the above-described cutting process or the like, but can be manufactured by casting. When manufactured by casting, the annular portion 7 and the column portion 8 are made of a material mainly composed of copper, for example, a brass alloy such as CAC301 or CAC302 standardized by JIS H5120, or a bronze alloy such as CAC406 or CAC407. Etc. can be used.

  In addition, the cage 6 is not limited to metal, and may be a synthetic resin injection-molded product. For example, polyphenylene sulfide resin (PPS resin), polyamide 46 (PA46), or the like is used as the resin material.

  It is preferable to provide means for preventing the cylindrical roller 5 from coming off from the pocket 9 in the axial direction. For example, as shown in FIG. 6, a roller retaining portion 14 with which the end surface 5 a of the cylindrical roller 5 engages can be provided at the opening edge in the axial direction of the pocket 9.

  The roller retaining portion 14 is formed at the tip portion of each column portion 8 and protrudes inward from the side surface 9 a of the pocket 9, and the protruding portion has a tapered surface 15 inclined inward toward the pocket 9. Is provided.

  The cylindrical roller 5 is accommodated in the pocket 9 by pressing the end face 5 a of the cylindrical roller 5 against the tapered surface 15 of the roller retaining part 14 to spread the roller retaining part 14. The cylindrical roller 5 in the pocket 9 is prevented from coming off in the axial direction because the retaining portion 14 is engaged with the end surface 5a on the inner side in the axial direction.

Furthermore, as described above, the side surface 9a of the pocket 9 is formed with a cylindrical surface along the outer peripheral surface of the cylindrical roller 5, so that the cylindrical roller 5 does not fall off from the upper and lower openings of the pocket 9. The cage 6 can maintain a state in which the cylindrical roller 5 is held in the pocket 9, and can be easily incorporated in the thrust roller bearing in this state.

  The cage 6 formed with such a roller retaining portion 14 is difficult to be machined with a rotary processing tool, and thus is preferably manufactured by casting or injection molding.

  The retaining portion 14 is not limited to the form shown in FIG. 6, and as shown in FIG. 7, as shown in FIG. Only a range of 5 roller lengths) may be formed on the cylindrical surface, and may be formed by a portion protruding in the circumferential direction from the axially inner side of the cylindrical surface.

  Further, as shown in FIG. 8, the cage 6 can be a bisected cage divided into two in the circumferential direction. The cage 6 is composed of a pair of cage segments 6a and 6b that are divided in the circumferential direction at the positions of the two pillars facing each other in the diameter direction of the annular portion 7, and the cage segments 6a and 6b The slits are connected to each other and integrated into an annular shape.

  As shown in FIG. 9A, a connecting portion 6c that protrudes in the circumferential direction is formed at the slit portion of both the cage divided bodies 6a and 6b. At the tip of the connecting portion 6c, a radial protrusion 6d protruding in one axial direction and a radial groove 6e provided between the protrusion 6d and the slit portion are formed.

  The connecting portions 6c of the cage divided body 6a and the cage divided body 6b are overlapped with each other, and the protrusions 6d and the grooves 6e are alternately fitted. By this fitting, the slit part is easily coupled, and the cage divided body 6a and the cage divided body 6b are integrated (see FIG. 9B).

  Thus, by making the cage 6 into a split cage, the cage can be easily formed by cutting.

DESCRIPTION OF SYMBOLS 1 washer 2 washer 3 track 4 track 5 cylindrical roller 5a end surface 6 cage 6a cage division body 6b cage division body 6c connection part 6d protrusion 6e groove 7 annular part 8 pillar part 9 pocket 9a side face 9b end face 11 workpiece DESCRIPTION OF SYMBOLS 12 Rotating tool 12a End surface 13 Rotating shaft 14 Retaining part 15 Tapered surface 21a Upper outer ring part 21b Lower outer ring part 22a Upper inner ring part 22b Lower inner ring part 23a Column part 23b Column part 24 Cylindrical roller 25 Screw

Claims (10)

  An annular portion, and a plurality of pillar portions that protrude radially inward from the annular portion and that are provided integrally with the annular portion at intervals in the circumferential direction, and the roller is formed by the annular portion and the adjacent pillar portion. A thrust roller bearing cage in which a pocket for storing the roller is formed, a cylindrical surface along the outer peripheral surface of the roller is formed on a side surface of the pocket, and the roller can be held.   The thrust roller bearing retainer according to claim 1, wherein a stopper means for engaging with an end face of the roller is provided at a tip portion of the column portion forming the pocket.   The thrust roller bearing retainer according to claim 1 or 2, wherein an end surface of the pocket is a flat surface.   A pair of cage divisions are formed by dividing the annular portion into two circumferentially at the positions of the two pillar portions facing each other in the diametrical direction, and the split portions of the cage division are coupled to each other. The thrust roller bearing retainer according to any one of claims 1 to 3, wherein the retainer is integrated in an annular shape.   A connecting portion that protrudes in the circumferential direction is formed in the split portion of each of the cage divided bodies, and the connecting portion is formed at a tip thereof in a radial direction protruding in one axial direction, the protruding portion, and the protrusion The thrust roller according to claim 4, further comprising a radial groove provided between the split opening, the connecting portions of the two cage divided bodies being overlapped with each other, and the protrusion and the groove being fitted together. Bearing cage.   The thrust roller bearing retainer according to any one of claims 1 to 5, wherein the annular portion and the plurality of column portions are integrally formed by casting.   The thrust roller bearing retainer according to any one of claims 1 to 5, wherein the annular portion and the plurality of column portions are integrally formed by injection molding.   The thrust roller bearing cage according to any one of claims 1 to 6, wherein the annular portion and the plurality of column portions are formed of a material mainly composed of copper.   The thrust roller bearing retainer according to any one of claims 1 to 5 or 7, wherein the annular portion and the plurality of column portions are formed of a synthetic resin. In a thrust roller bearing provided with a cage that holds a plurality of rollers interposed between a pair of washer circumferentially at intervals,
A thrust roller bearing, wherein the cage is the thrust roller bearing cage according to any one of claims 1 to 9.

Images