JP2014047815A - Rotation supporter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To attain a structure that can sufficiently bear a load even in any load area in a case of changing the load of a shell-shaped needle bearing, and can prevent loss torque based on the rotation resistance of a bearing part from uselessly increasing.SOLUTION: The radial gap of a first bearing part 18 is properly made smaller than the radial gap of a second bearing part 19. Consequently, in a state where a load is relatively small, the load is borne only with the first bearing part 18, and in a state where a load is relatively large, the load is borne with the first and second bearing parts 18, 19.

Description

  The present invention relates to an improvement in a rotation support device used by being incorporated in various mechanical devices such as transmissions for various vehicles such as automobiles and motorcycles, machine tools, and construction machines.

  As shown in FIG. 5, in the automobile transmission, the end of the rotary shaft 1 that is a part of the gear shaft and the shaft member is connected to the housing 2 that is the outer diameter side member by the shell-type needle bearing 3. It is supported rotatably. For this purpose, a mounting hole 4 is provided in a part of the housing 2, and the shell needle bearing 3 is assembled between the inner peripheral surface of the mounting hole 4 and the outer peripheral surface of the end portion of the rotary shaft 1. Yes.

  This shell-type needle bearing 3 is a double-row type described in Patent Document 1 or the like and has been widely known, and includes a shell-type outer ring 5, a plurality of radial needles 6, 6, and a pair of Radial cages 7 and 7 are provided. Among these, the shell-shaped outer ring 5 is formed by subjecting a hard metal plate material such as case-hardened steel or bearing steel, which is a metal plate, to plastic processing such as drawing, and includes a cylindrical portion 8 and the cylindrical portion. 8 is provided with a pair of inward flange portions 9 and 9 formed by bending both axial end portions in the radial direction. A pair of outer ring raceways 10 and 10 are formed on both axial halves of the inner peripheral surface of the cylindrical portion 8, which is a single cylindrical surface. Such a shell-shaped outer ring 5 is fixed to the housing 2 by internally fitting the cylindrical portion 8 into the mounting hole 4 with an interference fit having a uniform fastening allowance as a whole. Further, a portion of the outer peripheral surface of the end portion of the rotating shaft 1 that is a single cylindrical surface is opposed to the outer ring raceways 10 and 10 as a pair of inner ring raceways 11 and 11. Each of the radial needles 6, 6, each made of steel, is made of a steel plate between the outer ring raceways 10, 10 and the inner ring raceways 11, 11. It is provided so as to be able to roll while being held by the radial holders 7 and 7.

  By the way, the magnitude | size of the load load of the rolling bearing used by incorporating in the rotation support part of the gear shaft which comprises the transmission for motor vehicles like the shell type needle bearing 3 mentioned above changes at the time of use. For this reason, the rolling bearing is required to have a load capacity that can sufficiently support the maximum value of the load. On the other hand, in the case of the shell-type needle bearing 3 described above, since the rows of the radial needles 6 and 6 are double rows, it is easy to ensure a load capacity large enough to meet the requirements.

However, in the case of the conventional structure described above, there is room for improvement in the following points.
That is, in the case of the above-described conventional structure, the specifications of the bearing portions in both rows (the diameter of the outer ring raceway 10, the diameter of the inner ring raceway 11, the diameter and number of rolling surfaces of the radial needles 6 and 6, etc. ) Are equal to each other. Further, the tightening margin of the fitting portion between the mounting hole 4 and the cylindrical portion 8 constituting the shell-shaped outer ring 5 is uniform throughout (the diameter reduction amount of the outer ring raceways 10 and 10 accompanying the fitting is the same). )It has become. For this reason, the radial clearances (internal clearances in the radial direction) of the bearing portions in both rows are equal to each other. Therefore, regardless of the magnitude of the load that changes during use, the load is always shared and supported by the bearing portions of both rows. In other words, this load is not limited to the case where the load is large enough to be supported if it is not shared by the bearings in both rows, but when the load is small enough to be supported by only one of the rows. Moreover, it will be in the state which shares and supports the said load load by the bearing part of both rows.
On the other hand, with respect to the bearings in both rows, the load load is supported (the load zone is generated) rather than the load load is not supported (the load zone is not generated). The rotation resistance becomes larger.
Therefore, in the case of the conventional structure described above, the bearing portions of both rows are originally in a state where the load load can be supported by only one of the bearing portions (the load load is relatively small). There is a tendency that the loss torque (dynamic torque) based on the rotational resistance of the motor becomes uselessly large.

  Note that a dual clutch transmission (DCT), which is a kind of transmission for automobiles and motorcycles, has a mounting hole provided in a central portion in the radial direction of an outer diameter side gear shaft that is an outer diameter side member that rotates during use. A rotation support device is assembled between a peripheral surface and an outer peripheral surface of an inner diameter side gear shaft that is a shaft member that rotates in use. In use, the gear shafts rotate relative to each other, and the rolling bearing allows the gear shafts to rotate relative to each other while bearing a radial load acting between the gear shafts. Even when a double-row shell-type needle bearing is used as the rolling bearing constituting such a rotation support device, the above-described problem also occurs.

Japanese Patent Laid-Open No. 2005-42879

  In view of the circumstances as described above, the present invention can sufficiently support this load load in any load load region in an application in which the magnitude of the load load changes during use. The present invention has been invented to realize a structure capable of suppressing the loss torque based on the rotational resistance from increasing unnecessarily.

The rotation support device of the present invention includes an outer diameter side member having an attachment hole, a shaft member provided concentrically with the attachment hole on the inner diameter side of the attachment hole, an inner peripheral surface of the attachment hole, and a shaft member. And a shell-type needle bearing assembled with the outer peripheral surface.
Of these, the shell type needle bearing includes a shell type outer ring and a plurality of radial needles.
Of these, the shell-shaped outer ring is made of a metal plate and has cylindrical outer ring raceways at a plurality of axial positions on the inner peripheral surface, and is fitted and fixed in the mounting hole.
Each of the radial needles is provided between the outer ring raceway and a pair of inner ring raceways each provided on a portion of the outer peripheral surface of the shaft member facing the outer raceway. In addition, a plurality of pieces are provided for both rows so as to be freely rollable.
In particular, in the rotation support device of the present invention, the shell type needle bearing is configured in a state where the shell type needle bearing is assembled between the inner peripheral surface of the mounting hole and the outer peripheral surface of the shaft member. The radial gaps of the bearing portions in each row are made different from each other.
In the present invention, the outer diameter side member may be a housing that does not rotate even when used, and the shaft member may be implemented as a rotating shaft that rotates when used, or the outer diameter side member may be used. In addition to a rotating body that rotates sometimes, the shaft member can be implemented as a stationary shaft (fixed shaft) that does not rotate during use. Furthermore, regarding the configuration of the outer diameter side member and the shaft member, the configuration of the invention described in claim 6 described later can be employed.

When practicing the present invention, preferably, as in the invention described in claim 2, the basic dynamic load rating of each bearing portion is increased as the bearing portion has a smaller radial clearance.
In this case, for example, as in the invention described in claim 3, as a means for increasing the basic dynamic load rating of each bearing portion as the bearing portion having a smaller radial clearance, the number of the radial needles is set as the radial clearance. The means for increasing the bearing portion with a smaller diameter, the means for increasing the diameter of the rolling surface of the radial needle with a bearing portion with a smaller radial clearance, and the axial length of the rolling surface of the radial needle with a radial At least one means selected from the means for increasing the bearing portion with a smaller clearance can be employed.
Further, in this case, for example, as in the invention described in claim 4, the bearings in which the diameter of the outer ring raceway and the diameter of the inner ring raceway constituting each bearing portion are made larger in basic dynamic load rating, respectively. The department can be enlarged.
Further, when adopting a means for increasing the diameter of the rolling surface of the radial needle as the bearing portion having a smaller radial clearance, the bearing portions are configured as in the invention described in claim 5, for example. The diameter of the inner ring raceway is made equal to each other between the bearing portions, and the diameter of the outer ring raceway constituting each bearing portion is made larger as the bearing portion having a larger diameter of the rolling surface of the radial needle. .

  When carrying out the present invention, for example, as in the invention described in claim 6, the outer diameter side member is a rotating member that rotates around the central axis of the mounting hole when in use, and the shaft member Can be used as a rotating shaft that rotates about its own central axis when used, and the rotating member and the rotating shaft can be used in a state of rotating relative to each other. The invention described in claim 6 can be implemented as a rotary support device used by being incorporated in the DCT described above, for example. That is, in this case, the rotating member that is the outer diameter side member is the outer diameter side gear shaft, the rotating shaft that is the shaft member is the inner diameter side gear shaft, and the shell needle bearing is the outer diameter side shaft. A rolling bearing assembled between the inner peripheral surface of the mounting hole of the side gear shaft and the outer peripheral surface of the inner diameter side gear shaft.

  In the case of carrying out the present invention, the outer diameter side member is a housing that does not rotate even when used, the shaft member is a rotating shaft that rotates when used, and the shell needle bearing is one end of the rotating shaft. Assemble between the outer peripheral surface of the portion and the inner peripheral surface of the mounting hole, and at a position farther from one end edge of the rotating shaft than the bearing portion of each row constituting the shell-type needle bearing with a part of the rotating shaft. When used in a state where a radial load is applied, preferably, as in the invention described in claim 7, the radial gaps of the bearing portions of the respective rows exist at positions farther from one end edge of the rotary shaft. Make the bearing part smaller.

In carrying out the present invention, preferably, as in the invention described in claim 8, adjacent to each other in the axial direction at a portion between the inner peripheral surface of the shell-shaped outer ring and the outer peripheral surface of the shaft member. An annular spacer is arranged between the radial needles constituting the matching bearing portion.
When carrying out the present invention, for example, as in the invention described in claim 9, a stepped surface provided in a part of the inner peripheral surface of the shell-shaped outer ring in the axial direction and an axis of the outer peripheral surface of the shaft member. A thrust bearing can be installed between the step surface provided in a part of the direction. The thrust bearing includes a pair of thrust raceway surfaces opposed to each other in the axial direction, and a plurality of thrust needles provided between the thrust raceway surfaces so as to be able to roll while being held by a thrust holder. It is equipped with. The two thrust raceway surfaces may be provided on the side surfaces of the thrust raceway rings formed separately from the shell-shaped outer ring and the shaft member, respectively, or at least one of the two step surfaces, The thrust raceway surface can also be used.

  In the case of the rotary support device of the present invention configured as described above, only a small load is acting on the shell-type needle bearing (for example, only a load based on a preload set at the time of operation stop is acting. Load load begins to be generated immediately after the start of operation, and the transmission torque is small), among the bearings in each row, a load zone is generated only in the bearing with the smallest radial clearance. It will be in the state. From this state, when the load increases, the amount of elastic deformation of each member increases accordingly, and the bearings in the remaining rows also generate load zones in order from the smallest radial clearance. Begin to. Eventually, a load zone is generated in the bearing portions of all rows. In any state, the load is supported only by the bearing portion where the load zone is generated. Further, the rotational resistance of the bearings in each row is smaller in the state where the load area is not generated than in the state where the load area is generated. Therefore, in the case of the present invention, if the radial gaps of the bearing portions in each row are appropriately regulated in consideration of the range of the load load that changes during use, the load load is not limited regardless of the magnitude of the load load. The load can be shared and supported by the minimum number of bearings. As a result, it is possible to sufficiently support this load load in any load load region, and it is possible to prevent the loss torque based on the rotational resistance of the bearing portions of each row from becoming unnecessarily large.

Moreover, if the structure of the invention described in claim 2 is adopted, it is possible to easily balance the life of the bearing portions in each row. In other words, in the case of the present invention, the bearing portion with a smaller radial gap is in a state of supporting this load load from the stage where the load load is smaller. For this reason, the load frequency (support time) of the load is increased (longer) as the bearing portion has a smaller radial clearance. Further, in the case of the present invention, when the load load is shared and supported by a plurality of bearing portions, the width of the load zone generated in each of the bearing portions becomes wider as the bearing portion having a smaller radial clearance. That is, the load sharing ratio of the load is increased as the bearing portion has a smaller radial clearance. Therefore, in the case of the present invention, a bearing portion with a smaller radial clearance is used under severe load conditions. On the other hand, in the case of the invention described in claim 2, the basic dynamic load rating of the bearings in each row is set so that the bearings with smaller radial clearances (the bearings used under more severe load conditions). ), Bigger. For this reason, it is possible to easily balance the lifetimes of the bearing portions in each row.
If the configuration of the invention described in claim 5 is adopted, it is not necessary to form a step surface between the inner ring raceways adjacent in the axial direction at a part of the outer peripheral surface of the shaft member. Therefore, the shaft member can be easily processed accordingly.

In addition, if the configuration of the invention described in claim 7 is adopted, a bearing portion having a smaller radial clearance is arranged in order from a portion close to the point of action of the radial load in one end portion of the rotating shaft as the shaft member. It becomes a state. For this reason, the bending rigidity of the said rotating shaft with respect to the said radial load can be ensured efficiently.
Further, if the configuration of the invention described in claim 8 is adopted, the axial displacement of the radial needle constituting the pair of bearing portions disposed on both sides in the axial direction of the spacer is regulated by the annular spacer. Easy to do.
If the structure of the invention described in claim 9 is adopted, the thrust load acting between the shaft member and the mating member with the shell-shaped outer ring fitted therein can be supported by the thrust bearing. In addition, since the thrust bearing is assembled between the shell-shaped outer ring and the shaft member, the rotation support portion between the shaft member and the mating member can be made compact, and the rotation support portion can be configured with respect to the rotation support portion. The assemblability of the thrust bearing can be improved.

The fragmentary sectional view which shows the 1st example of embodiment of this invention. The fragmentary sectional view which shows the 2nd example. The fragmentary sectional view which shows the 3rd example. The fragmentary sectional view which shows the 4th example. The fragmentary sectional view which shows one example of the conventional structure.

[First example of embodiment]
FIG. 1 shows a first example of an embodiment of the present invention corresponding to claims 1 to 4 and 7. The rotation support device of this example includes a housing 2a that constitutes an automobile transmission, a rotation shaft 1a that is a gear shaft and a shaft member, and a shell-type needle bearing 3a. One end of the rotating shaft 1a is rotatably supported by the shell needle bearing 3a with respect to the housing 2a.

  The shell type needle bearing 3a includes a shell type outer ring 5a, a plurality of radial needles 6 and 6, and a pair of radial cages 7a and 7b. Of these, the shell-shaped outer ring 5a is formed by subjecting a hard metal plate material such as case-hardened steel, bearing steel or the like, which is a metal plate, to plastic processing such as drawing processing. It has a pair of inward flange portions 9a and 9b formed by bending both axial end portions of the stepped cylindrical portion 12 radially inward. Of these, the stepped cylindrical portion 12 includes a large-diameter cylindrical portion 13 and a small-diameter cylindrical portion 14 that are arranged concentrically with each other, and an annular portion 15 that connects the end edges in the axial direction of both the cylindrical portions 13 and 14. Consists of. The inner peripheral surfaces of the cylindrical portions 13 and 14, each of which is a cylindrical surface, serve as a pair of outer ring raceways 10a and 10b. In the shell-shaped outer ring 5a having such a configuration, both the cylindrical portions 13 and 14 are fitted into the inner peripheral surface of the stepped mounting hole 4a provided in a part of the housing 2a by an interference fit. . At the same time, the outer surface of the inner flange 9b on the smaller diameter side of the inner flanges 9a, 9b and the outer surface of the ring portion 15 are provided on the inner peripheral surface of the mounting hole 4a. By abutting against the step surface, the shell-shaped outer ring 5a is positioned in the axial direction with respect to the housing 2a.

  Further, one end portion of the rotating shaft 1a, which is made of steel, is disposed concentrically with the shell-shaped outer ring 5a on the inner diameter side of the shell-shaped outer ring 5a. One end of the rotating shaft 1a is formed by concentrically providing a small-diameter portion 16 on the tip side (left side in FIG. 1) and a large-diameter portion 17 on the center side (right side in FIG. 1). The outer peripheral surface of the large-diameter portion 17 and the outer peripheral surface of the small-diameter portion 16, each of which is a cylindrical surface, are used as a pair of inner ring raceways 11a and 11b.

  Further, each of the radial needles 6, 6, each made of steel, is made of a steel plate between the outer ring raceways 10 a, 10 b and the inner ring raceways 11 a, 11 b. It is provided so that it can roll while being held by the radial holders 7a and 7b. Further, in this state, each includes an outer ring raceway 10a (10b), an inner ring raceway 11a (11b), a plurality of radial needles 6 and 6, and a radial cage 7a (7b) for each row. The radial needles 6, 6 and the radial cage 7 a constituting the first bearing portion 18 on the large diameter side of the bearing portions 18, 19 in both rows are the inner surface of the inward flange portion 9 a on the large diameter side and the ring. The axial displacement is restricted by the inner surface of the portion 15. On the other hand, the radial needles 6 and 6 and the radial cage 7b constituting the second bearing portion 18 on the small diameter side are among the inner surface of the inward flange portion 9b on the small diameter side and the outer peripheral surface of the rotating shaft 1a. The axial displacement is regulated by the step surface 20 provided between the inner ring raceways 11a and 11b. Further, in the case of this example, the radial needles 6 and 6 are the same in the two rows of bearing portions 18 and 19 having the same specifications.

  In the case of the present example, the radial gap between the first and second bearing portions 18 and 19 is arranged on the side far from the one end edge (tip edge) of the rotary shaft 1a (the axial center). The bearing portion 18 is smaller than the second bearing portion 19 disposed on the side close to the one end edge (close to the end portion in the axial direction). For this reason, in the case of this example, the assembly state shown in the figure (with the inner fitting of the shell-shaped outer ring 5a into the mounting hole 4a by the interference fit, both the outer ring raceways 10a and 10b are elastically reduced in diameter. In this state, the diameter difference between the outer ring raceway 10a and the inner ring raceway 11a constituting the first bearing portion 18 is determined from the diameter difference between the outer ring raceway 10b and the inner ring raceway 11b constituting the second bearing portion 19. Is also small.

  Further, in this example, the basic dynamic load rating of the first and second bearing portions 18 and 19 is the first bearing portion 18 having a relatively small radial gap and the second bearing portion 19 having a relatively large radial gap. Is bigger than. For this reason, in the case of this example, the number of radial needles 6, 6 constituting the first bearing portion 18 is made larger than the number of radial needles 6, 6 constituting the second bearing portion 19. Yes. Here, in the case of this example, the installation space (cylindrical space) of the radial needles 6 and 6 constituting the first bearing portion 18 is the installation space of the radial needles 6 and 6 constituting the second bearing portion 19 ( Since the diameter dimension is larger than the cylindrical space), the circumferential length is also longer. Therefore, as described above, it is easy to increase the number of radial needles 6 and 6 constituting the first bearing portion 18 as compared with the number of radial needles 6 and 6 constituting the second bearing portion 19.

  In the case of this example, the other end (not shown) of the rotary shaft 1a is rotatably supported by another rolling bearing with respect to the housing 2a. A gear is fixed to an axial intermediate portion (not shown) of the rotary shaft 1a. During the operation of the automobile transmission, a radial load acts on the intermediate portion in the axial direction of the rotary shaft 1a via the gear. The magnitude of the radial load varies depending on the driving state of the automobile transmission (the greater the transmission torque, the larger the radial load). Along with this, the magnitudes of the load loads of the shell-type needle bearing 3a and the other rolling bearings also change.

  In the case of the rotary support device of the present example configured as described above, only a very small load is acting on the shell-type needle bearing 3a (for example, only a load based on a preload set at the time of operation stop). In the state where the load is applied, the state where the load starts to be generated immediately after the start of operation, and the state where the torque transmitted by the rotating shaft 1a is small). Of these, only the first bearing portion 18 having a relatively small radial gap is in a state where a load zone is generated. From this state, when the load increases, the amount of elastic deformation of each member increases accordingly, and a load zone also starts to occur in the second bearing portion 19 having a relatively large radial gap. That is, when the load increases beyond a certain value, load zones are generated in the first and second bearing portions 18 and 19, respectively. In any state, the load is supported only by the bearing portion where the load zone is generated. Further, the rotational resistance of the first and second bearing portions 18 and 19 is smaller in the state where the load area is not generated than in the state where the load area is generated. Therefore, in the case of this example, if the radial gap between the first and second bearing portions 18 and 19 is appropriately regulated in consideration of the range of the load load that changes during use, the magnitude of the load load is increased. Regardless of this, this load can be supported alone or in a shared manner by the minimum number (one or two rows) of bearing portions 18 (19). As a result, it is possible to sufficiently support the load load in any load load region, and it is possible to suppress the loss torque based on the rotational resistances of the first and second bearing portions 18 and 19 from becoming unnecessarily large.

  In the case of this example, the first bearing portion 18 having a relatively small radial gap is in a state of supporting this load load from the stage where the load load is smaller than that of the second bearing portion 19 having a relatively large radial gap. become. For this reason, the load frequency (support time) of the load is greater (longer) at the first bearing portion 18 than at the second bearing portion 19. In the case of this example, when the load load is shared and supported by the first and second bearing portions 18 and 19, the load range generated in the first and second bearing portions 18 and 19. The first bearing portion 18 having a relatively small radial gap is wider than the second bearing portion 19 having a relatively large radial gap. That is, the load sharing ratio of the load load is greater in the first bearing portion 18 than in the second bearing portion 19. Therefore, in the case of this example, the first bearing portion 18 is used under severer load conditions than the second bearing portion 19. On the other hand, in the case of this example, the basic dynamic load rating of the first bearing portion 18 used under relatively severe load conditions is the same as the basic dynamic load rating of the second bearing portion 19 used under relatively loose load conditions. It is larger than the rated load. For this reason, in the case of this example, compared with the case where the basic dynamic load ratings of the first and second bearing portions 18 and 19 are equal to each other, these first and second bearing portions 18 are used. , 19 lifespans can be brought close to each other.

  In the case of this example, among the first and second bearing portions 18 and 19, the first bearing portion 18 where the load zone is generated first with the increase of the load load is generated later. It arrange | positions in the position near the axial direction intermediate part which is an action point of the radial load of the said rotating shaft 1a rather than the 2nd bearing part 19 to do. For this reason, the span of the rotating shaft 1a (the interval between the pair of bearing portions provided at both ends in the axial direction) is shortened, and the bending rigidity of the rotating shaft 1a with respect to the radial load can be efficiently secured.

[Second Example of Embodiment]
FIG. 2 shows a second example of an embodiment of the present invention corresponding to claims 1 to 4, 7 and 8. In the case of this example, in the portion between the inner peripheral surface of the shell-shaped outer ring 5a and the outer peripheral surface of the rotary shaft 1a, the portion between the first and second bearing portions 18, 19 (more specifically, With respect to the axial direction, an annular spacer 21 is disposed on the inner surface of the annular portion 15 of the shell-shaped outer ring 5a and the stepped surface 20 of the rotating shaft 1a. The spacer 21 regulates the displacement of the radial cages 7a and 7b and the radial needles 6 and 6 constituting the first and second bearing portions 18 and 19 in the approaching direction. In addition, although the material which comprises the said spacer 21 is not specifically limited, Preferably, it is good to use the material (for example, oil-containing metal, highly functional resin) which has high intensity | strength and is easy to slip.
Since the structure and operation of the other parts are the same as in the case of the first example shown in FIG. 1 described above, the same parts are denoted by the same reference numerals, and redundant description is omitted.

[Third example of embodiment]
FIG. 3 shows a third example of an embodiment of the present invention corresponding to claims 1 to 3, 5, 7 and 8. In the case of this example, in order to make the basic dynamic load rating of the first bearing portion 18a with a relatively small radial gap larger than the basic dynamic load rating of the second bearing portion 19 with a relatively large radial gap, The diameter of the rolling surface of the radial needles 6a, 6a constituting the first bearing portion 18a is made larger than the diameter of the rolling surface of the radial needles 6, 6 constituting the second bearing portion 19. That is, in the case of this example, the outer peripheral surface of one end portion of the rotary shaft 1b is a single cylindrical surface, and the outer diameter dimensions of the inner ring raceways 11c and 11b provided on the outer peripheral surface of the one end portion are made equal to each other. ing. Thus, the radial width between the outer ring raceway 10a and the inner ring raceway 11c constituting the first bearing portion 18a is set to the radial direction between the outer ring raceway 10b and the inner ring raceway 11b constituting the second bearing portion 19. By making it sufficiently larger than the width, the rolling surfaces of the radial needles 6a, 6 can have a diameter difference between the bearing portions 18a, 19 as described above. In the case of carrying out the structure of this example, if the basic dynamic load rating of the first bearing portion 18a is within a range that can be larger than the basic dynamic load rating of the second bearing portion 19, these first and first The number of radial needles 6a, 6 constituting the two-bearing portions 18a, 19 may be different from each other or may be equal to each other.
Since the structure and operation of the other parts are the same as in the case of the second example shown in FIG. 2 described above, the same parts are denoted by the same reference numerals, and redundant description is omitted.

[Fourth Example of Embodiment]
FIG. 4 shows a fourth example of the embodiment of the invention corresponding to claims 1 to 4, 7, and 9. In the case of this example, the thrust bearing 22 is assembled to a portion adjacent to the first bearing portion 18 on the opposite side to the second bearing portion 19 between the shell-shaped outer ring 5b and the rotary shaft 1c. Yes. For this purpose, the second circular ring portion 23 is provided in a state of being bent at a right angle radially outward from the inner end edge (the right end edge in FIG. 4) of the large-diameter cylindrical portion 13 constituting the shell-shaped outer ring 5b. The second large-diameter cylindrical portion 24 is provided so as to be bent at a right angle from the outer peripheral edge of the second annular portion 23 to the axially inner side (right side in FIG. 4). In addition, a second large diameter portion 25 having a larger outer diameter than the large diameter portion 17 is provided in a portion adjacent to the proximal end side of the large diameter portion 17 at a portion near one end of the rotary shaft 1c. A third large diameter portion 26 having a larger outer diameter than the second large diameter portion 25 is provided in a portion adjacent to the proximal end side of the second large diameter portion 25. And in the state which has arrange | positioned the said thrust bearing 22 in the part between the internal peripheral surface of said 2nd large diameter cylindrical part 24, and the outer peripheral surface of said 2nd large diameter part 25, this thrust bearing 22 is a level | step difference surface. The second annular portion 23 is sandwiched between an inner surface and a stepped surface 27 existing between the outer peripheral surface of the second large diameter portion 25 and the outer peripheral surface of the third large diameter portion 26. . In the illustrated state of use, the outer surface of the second annular portion 23 is in contact with a stepped surface provided on the inner surface of the mounting hole 4b of the housing 2b.

  The thrust bearing 22 includes a pair of thrust raceways 30 and 31 each having an annular inner raceway surface 28 and 29 that are opposed to each other in the axial direction, each made of a steel plate, and both thrust raceways. A plurality of thrust needles 33 and 33 each made of steel are provided between the surfaces 28 and 29 so as to be able to roll while being held by a thrust retainer 32 made of a steel plate. Of the two thrust raceways 30, 31, the outer surface of one thrust raceway 30 is the stepped surface 27, and the outer surface of the other thrust raceway 31 is the inner surface of the second annular ring portion 23. , Respectively. In the case of this example, the radial cage 7 a and the radial needles 6, 6 constituting the second bearing portion 19 are between the outer peripheral surface of the large diameter portion 17 and the outer peripheral surface of the second large diameter portion 25. The displacement inward in the axial direction is restricted by the step surface 34 existing in

According to the rotation support device of this example configured as described above, the thrust load acting between the rotating shaft 1c and the housing 2b can be supported by the thrust bearing 22. Further, since the thrust bearing 22 is assembled between the shell-shaped outer ring 5b and the rotary shaft 1c, the rotation support portion at one end of the rotary shaft 1c with respect to the housing 2b can be made compact, and this The assembling property of the thrust bearing 22 to the rotation support portion can be improved.
Since the structure and operation of the other parts are the same as in the case of the first example shown in FIG. 1 described above, the same parts are denoted by the same reference numerals, and redundant description is omitted.

Although not shown in each of the above-described embodiments, when the present invention is implemented, as a means for varying the basic dynamic load rating of the bearing portions in each row, the radial needle rolling for each bearing portion in each row. It is also possible to adopt means for varying the axial length of the surface.
Moreover, when providing a thrust bearing, this thrust bearing can also be arrange | positioned between the bearing parts adjacent to an axial direction.

DESCRIPTION OF SYMBOLS 1, 1a-1c Rotating shaft 2, 2a, 2b Housing 3, 3a-3d Shell type needle bearing 4, 4a, 4b Mounting hole 5, 5a, 5b Shell type outer ring 6, 6a Radial needle 7, 7a-7c Radial cage 8 Cylindrical portion 9, 9a, 9b Inward flange portion 10, 10a, 10b Outer ring raceway 11, 11a-11c Inner ring raceway 12 Stepped cylindrical portion 13 Large diameter cylindrical portion 14 Small diameter cylindrical portion 15 Circular ring portion 16 Small diameter portion 17 Large diameter portion 18, 18a First bearing portion 19 Second bearing portion 20 Stepped surface 21 Spacer 22 Thrust bearing 23 Second annular portion 24 Second large diameter cylindrical portion 25 Second large diameter portion 26 Third large diameter portion 27 Stepped surface 28 Thrust raceway surface 29 Thrust raceway surface 30 Thrust raceway ring 31 Thrust raceway ring 32 Thrust retainer 33 Thrust needle 34 Step surface

Claims (9)

The outer diameter side member having the mounting hole, the shaft member provided concentrically with the mounting hole on the inner diameter side of the mounting hole, and the inner peripheral surface of the mounting hole and the outer peripheral surface of the shaft member are assembled. Shell-type needle bearings,
The shell needle bearing includes a shell outer ring and a plurality of radial needles.
Of these, the shell-shaped outer ring is made of a metal plate and has cylindrical outer ring raceways at a plurality of axial positions on the inner peripheral surface, and is fitted and fixed in the mounting hole.
Each of the radial needles is provided between the outer ring raceway and a pair of inner ring raceways each having a cylindrical surface provided on a portion of the outer peripheral surface of the shaft member facing the outer raceway. Multiple rolls are provided for both rows,
In the rotation support device,
When the shell-type needle bearings are assembled between the inner peripheral surface of the mounting hole and the outer peripheral surface of the shaft member, the radial clearances of the bearing portions of the rows constituting the shell-type needle bearings are different from each other. Rotating support device characterized by that.   The rotation support device according to claim 1, wherein the basic dynamic load rating of each bearing portion is increased as the bearing portion has a smaller radial clearance.   Means for increasing the basic dynamic load rating of each bearing portion as the bearing portion with a smaller radial clearance, means for increasing the number of the radial needles with a bearing portion with a smaller radial clearance, and rolling of the radial needle The diameter of the surface is selected from a means for increasing the bearing portion with a smaller radial clearance, and a means for increasing the axial length of the rolling surface of the radial needle as the bearing portion with a smaller radial clearance. The rotation support device according to claim 2, wherein at least one means is employed.   4. The rotation support device according to claim 3, wherein a diameter of the outer ring raceway and a diameter of the inner ring raceway constituting each bearing portion are increased as a bearing portion having a larger basic dynamic load rating.   A means for increasing the diameter of the rolling surface of the radial needle as the bearing portion having a smaller radial clearance is employed, and the diameters of the inner ring raceways constituting the bearing portions are equal to each other. In addition, the rotation support device according to claim 3, wherein the diameter of the outer ring raceway constituting each bearing portion is increased as the bearing portion having a larger diameter of the rolling surface of the radial needle.   The outer diameter side member is a rotating member that rotates around the central axis of the mounting hole when used, the shaft member is a rotating shaft that rotates about its own central axis when used, and the rotation The rotation support device according to any one of claims 1 to 5, wherein the member and the rotation shaft are used in a state of rotating relative to each other.   The outer diameter side member is a housing that does not rotate even when used, the shaft member is a rotating shaft that rotates when used, and the shell-type needle bearing has an outer peripheral surface of one end of the rotating shaft and the mounting hole. It is assembled between the inner peripheral surface, and the radial clearance of the bearing portions of each row constituting the shell-type needle bearing is smaller as the bearing portion is located farther from one end edge of the rotating shaft. The rotation according to any one of claims 1 to 5, wherein the rotation is used in a state in which a radial load acts on a part of the rotating shaft farther from one end edge of the rotating shaft than the bearings. Support device.   An annular spacer is arranged between the radial needles constituting the bearing portions adjacent to each other in the axial direction at a portion between the inner peripheral surface of the shell-shaped outer ring and the outer peripheral surface of the shaft member. The rotation support device according to any one of claims 1 to 7.   A thrust bearing is installed between a step surface provided in a part in the axial direction of the inner peripheral surface of the shell-shaped outer ring and a step surface provided in a part in the axial direction of the outer peripheral surface of the shaft member. Includes a pair of thrust raceway surfaces opposed to each other in the axial direction, and a plurality of thrust needles provided between the two thrust raceway surfaces so as to be able to roll while being held by a thrust retainer. The rotation support device according to claim 1, wherein the rotation support device is a device.

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