JP5810627B2 - Tandem angular ball bearings and outer ring side assemblies for tandem angular ball bearings - Google Patents

Description

  The present invention relates to an improvement in a tandem angular ball bearing that is incorporated in a rotary machine such as a differential gear and a transfer device for an automobile and supports a rotating shaft that rotates in a state where a radial load and a thrust load are applied.

  Various structures for rotatably supporting a pinion shaft constituting a differential gear for automobiles in a differential case are widely known as described in Patent Documents 1-6. When operating a differential device for automobiles, a large radial load and thrust load are simultaneously applied to the pinion shaft. Use a bearing that supports the pinion shaft with sufficiently large load capacity in both radial and thrust directions. There is a need to. For this reason, the pinion shaft is rotatably supported inside the differential case by using a pair of tapered roller bearings having different contact angles described in, for example, Patent Document 1 and having different contact angles. Yes.

  As is well known in the technical field of rolling bearings, tapered roller bearings have a larger dynamic torque (rotational resistance) instead of a larger load capacity than ball bearings. For this reason, due to the recent trend of reducing fuel consumption of automobiles, radial and thrust loads are applied as at least one of the pair of rolling bearings for supporting the pinion shaft with respect to the differential case. As described in Patent Document 1, it has been conventionally considered to use a tandem angular ball bearing that can be supported. Tandem angular ball bearings do not involve large sliding contact as in the case of tapered roller bearings during operation, so that the dynamic torque can be kept low and the resistance of the differential gear can be reduced.

  FIG. 15 shows an example of a conventional structure of a rotation support device for a pinion shaft for a differential gear, which is configured by an angular ball bearing described in Patent Document 2. Since the structure and operation of the entire differential gear are well known and described in Patent Documents 1 to 6, the illustration and detailed description are omitted, and only the structure of the rotation support device portion will be described below. To do. A pair of ball bearings 1 and 2 are arranged inside the differential case in a state of being separated from each other, and the pinion shaft 3 is supported by these ball bearings 1 and 2. These ball bearings 1 and 2 are angular ball bearings in which the balls have contact angles, and the contact angles of these ball bearings 1 and 2 are opposite to each other. Therefore, the pinion shaft 3 is rotatably supported in the differential case in a state where not only a radial load but also a thrust load in both directions is supported.

  Among the ball bearings 1 and 2, a tandem angular ball bearing is used as the ball bearing 1 on the pinion gear 4 side (left side in FIG. 15, hereinafter referred to as “pinion gear side”) that supports a relatively large radial load and thrust load. Is used. On the other hand, the ball bearing 2 on the side opposite to the pinion gear 4 that supports only a relatively small radial load and thrust load (the right side in FIG. 15, hereinafter referred to as “anti-pinion gear side”) uses a single-row angular ball bearing. doing. In addition, as described in Patent Documents 2 to 6, a structure in which not only the pinion gear side but also the anti-pinion gear side has a tandem angular ball bearing has been conventionally known. The ball bearing 1 on the pinion gear side supports a thrust load in a direction away from the ring gear (not shown) meshed with the pinion gear 4 (rightward in FIG. 15) in addition to the radial load. On the other hand, the ball bearing 2 on the anti-pinion gear side supports a thrust load in a direction approaching the ring gear (leftward in FIG. 15) in addition to the radial load.

  In this example, the pinion gear-side ball bearing 1, which is a tandem angular ball bearing, includes an outer ring 5, an inner ring 6, a plurality of balls 7, and a pair of cages 8 and 9. The outer ring 5 is provided with double-row angular outer ring raceways 10 and 11 having different inner diameters on the inner peripheral surface. The inner diameters of both outer ring raceways 10 and 11 are larger in the outer ring raceway 10 on the pinion gear side, and smaller in the outer ring raceway 11 on the anti-pinion gear side. Further, the inner ring 6 is disposed concentrically with the outer ring 5 on the inner diameter side of the outer ring 5, and has a double row angular type in which outer diameters are different from each other in a portion of the outer peripheral surface facing both the outer ring raceways 10 and 11. Inner ring raceways 12 and 13 are provided. The outer diameters of both the inner ring raceways 12 and 13 are larger in the inner ring raceway 12 on the pinion gear side and smaller in the outer ring raceway 13 on the anti-pinion gear side. Further, each ball 7 is provided with a contact angle in the same direction (parallel combination type) in both rows between the outer raceways 10 and 11 and the inner raceways 12 and 13 in each row. In this state, it is provided so as to be able to roll freely. Further, both the cages 8 and 9 have different diameters, and each retains the balls 7 in both rows so as to roll freely. It should be noted that the diameters of the balls 7 in both rows may be the same or different from each other.

  Unlike the tapered roller bearing, the tandem angular ball bearing 1 of the first example of this conventional structure does not involve a large sliding contact during operation, so that the dynamic torque can be kept low and the resistance of the differential gear can be reduced. Further, since the balls 7 arranged in double rows support the radial load and the thrust load generated at the meshing portion of the pinion gear 4 and the ring gear, it is possible to sufficiently secure the load capacity regarding the loads in both directions. However, in this ball bearing 1, due to the tandem angular structure, the following improvements are required from the viewpoint of ensuring sufficient reliability in terms of durability.

  That is, the outer ring 5 constituting the ball bearing 1 needs to be fitted into the support hole 22 of the support portion 21 provided inside the differential case by an interference fit. Similarly, the inner ring 6 is fastened to the pinion shaft 3. It is necessary to externally fit. The reason for this is that during the operation of the differential gear, the occurrence of creep at the fitting portion between the outer ring 5 and the inner ring 6 and the mating member is prevented, and rattling due to wear occurs at these fitting portions. This is to prevent things. However, in a state where the constituent members of the ball bearing 1 are assembled so as not to be separated from each other, the outer ring 5 cannot be fitted and fixed to the support hole 22 and the inner ring 6 to the pinion shaft 3 by interference fit. The reason for this is that with this fitting and fixing work, Brinell indentations are formed in parts of both outer ring raceways 10 and 11 and both inner ring raceways 12 and 13 where the rolling surfaces of each ball 7 are in contact. This is because not only does it cause excessive vibration and noise during operation of the ball bearing 1, but also the durability is significantly impaired.

  For this reason, when the ball bearing 1 is assembled between the inner peripheral surface of the support hole 22 and the outer peripheral surface of the pinion shaft 3, for example, as described in Patent Document 3, the ball bearing 1 Before the assembly of each member is completed, the outer ring 5 is fitted into the support hole 22 by interference fitting, the inner ring 6 is fitted into the pinion shaft 3 by interference fitting, and the outer ring 5 and the inner ring 6 are then fitted. They are combined through each ball 7. At this time, prior to the combination of the outer ring 5 and the inner ring 6, each ball 7 has a circumferential surface portion of one of the race rings (inner diameter side portions of both outer ring races 10 and 11, or both inner ring raceways 12. , 13 on the outer diameter side portion), in a state of being held by both cages 8 and 9. Then, the other race ring is made to enter the inner diameter side portion or the outer diameter side portion of each ball 7 together with the member fitted and fixed to the other race ring. Then, the rolling surface of each ball 7 is brought into contact with the outer ring raceway and the inner ring raceway.

  During assembly of such a ball bearing 1, the differential case with the outer ring 5 fitted and fixed and the pinion shaft 3 with the inner ring 6 fitted and fixed are positioned with sufficient accuracy, and the central axis of the inner ring 6 and the outer ring If the inner ring 6 and the outer ring 5 are brought close to each other in the axial direction and the inner ring 6 is inserted into the inner diameter side of the outer ring 5 while the center axis of the outer ring 5 is accurately aligned, the durability of the ball bearing 1 after assembly There is no particular problem. However, the center axis of the inner ring 6 and the center axis of the outer ring 5 do not coincide with each other due to variations in accuracy of the assembling apparatus, poor adjustment, etc., for example, there is an inclination or eccentricity in these, or both rows When the inner ring 6 and the outer ring 5 are combined in a state in which there is a deviation in the arrangement state of each ball 7 such as an inclination between the balls 7, the rotation of each ball 7 held on one raceway ring There is a possibility that the moving surface and the peripheral surface of the other raceway will bump against each other vigorously or rub against each other. Such a possibility can also occur when the balls 7 held by the two cages 8 and 9 are arranged on the peripheral surface portion of one of the race rings.

  On the other hand, of the inner peripheral surface of the outer ring 5 and the outer peripheral surface of the inner ring 6, the outer ring raceways 10 and 11 and the inner ring raceways 12 and 13 are smooth polished surfaces. The surface may be rough or have sharp corners. When the outer ring 5 and the inner ring 6 are combined with each other, if these rough surfaces or corners strike against some of the rolling surfaces of the balls 7 or rub against each other, the rolling surfaces may be damaged. Damage can occur. The occurrence of such damage not only facilitates the generation of large vibrations and noise during operation of the differential gear incorporating the ball bearing 1, but also causes an excessive decrease in the life of the ball. It may impair durability.

16 to 18 show another example of the conventional structure of a tandem angular ball bearing described in Patent Document 6. FIG. The basic structure of the tandem angular ball bearing of the second example of the conventional structure is the same as that of the first example of the conventional structure. In addition, although it is the same also in a 1st example, the contact angle of the mutually same direction (parallel combination type) is provided to each ball 7 which comprises a large diameter side ball row, and each ball 7 which comprises a small diameter side ball row. Has been. The contact angles θ ₁ and θ ₂ of these two rows can be the same (θ ₁ = θ ₂ ) or different (θ ₁ ≠ θ ₂ ).

  In the second example of this conventional structure, the outer ring 5a is on one side in the axial direction of both the large diameter side and small diameter side outer ring raceways 10 and 11 ("one side in the axial direction" means the left side of FIGS. On the other hand, the right side of FIGS.16 to 18 is referred to as “other side” in the axial direction.) No groove shoulder is provided on the other side, and groove shoulders 16b and 17b are provided only on the other side in the axial direction. On the other hand, the inner ring 6a is provided with groove shoulders 18a, 18b, 19a, and 19b on both sides in the axial direction of both the large diameter side and small diameter side inner ring raceways 12 and 13, respectively. Further, both the large-diameter side and small-diameter side cages 8 and 9 hold the balls 7 in the pockets 14 and 15 so that the balls 7 come out from the pockets 14 and 15 in the radial direction. It is configured to prevent it.

  When assembling the tandem angular ball bearing of the second example of the conventional structure, first, an inner ring side assembly 31 as shown by a solid line in FIG. 17 is assembled. For this purpose, each ball 7 is held in the pockets 14 and 15 of both the large-diameter side and small-diameter side retainers 8 and 9 as indicated by chain lines in FIG. Each ball 7 held in each pocket 14 of the large-diameter side cage 8 is brought closest to the outer diameter side of the large-diameter side cage 8 without elastically deforming the large-diameter side cage 8. In this state, the diameter of the inscribed circle of each ball 7 is at least smaller than the outer diameters of the groove shoulder portions 18 a and 18 b existing on both axial sides of the large-diameter side inner ring raceway 12. Further, each ball 7 held in each pocket 15 of the small diameter side retainer 9 is in a state of being closest to the outer diameter side of the small diameter side retainer 9 without elastically deforming the small diameter side retainer 9. The diameter of the inscribed circle of each ball 7 is at least smaller than the outer diameter of the groove shoulder portions 19a, 19b existing on both axial sides of the small-diameter side inner ring raceway 13. If the balls 7 are held in the pockets 14 and 15 of the large-diameter side and small-diameter side cages 8 and 9 as described above, then these large-diameter sides are indicated as indicated by arrows in FIG. The balls 7 held by the small diameter side cages 8 and 9 are caused to enter the outer diameter side of the inner ring 6a from the other side in the axial direction of the inner ring 6a. As a result, as shown by the solid line in the figure, each ball 7 held by both the large diameter side and small diameter side cages 8 and 9 is moved to the outer diameter side of both the large diameter side and small diameter side inner ring raceways 12 and 13. Assemble. At this time, the balls 7 held by the large-diameter side and small-diameter side cages 8 and 9 are elastically deformed by the large-diameter side and small-diameter side cages 8 and 9, and the inscribed circles of these balls 7 are inscribed. Passing through each of the groove shoulders 18b, 19a, 19b while expanding the diameter. After passing, the diameter of the inscribed circle of each ball 7 is reduced by elastic restoration of both the large-diameter side and small-diameter side cages 8 and 9, and these balls 7 are both large-diameter side and small-diameter side inner ring raceways. 12 and 13 are assembled on the outer diameter side.

In this way, in the state where the inner ring side assembly 31 is completed, the balls 7 held by the large diameter side and small diameter side cages 8 and 9 are respectively connected to the large diameter side and small diameter side cages 8 and 9. The pocket shoulders 14a, 18b are prevented from slipping out from the inside of the pockets 14, 15 to the outer diameter side, and from slipping out from both the large diameter side and the small diameter side inner ring raceways 12, 13 in the axial direction. It is blocked by 19a and 19b. For this reason, the inner ring 6 a and the large-diameter side and small-diameter side cages 8 and 9 and the balls 7 can be handled integrally as the inner ring-side assembly 31. After the inner ring side assembly 31 is assembled, the inner ring side assembly 31 is then inserted into the inner diameter side of the outer ring 5a from one axial side of the outer ring 5a as shown in FIG. As a result, as shown in FIG. 16, the balls 7 held by both the large diameter side and small diameter side cages 8 and 9 are assembled to the inner diameter side of the large diameter side and small diameter side outer ring raceways 10 and 11. Complete assembly of tandem angular contact ball bearings. In the case of the second example of the conventional structure, there is no groove shoulder on each of the axially one side portions of the large-diameter side and small-diameter side outer ring raceways 10 and 11, and therefore the inner ring side assembly 31 as described above. Can be inserted smoothly.

  In the second example of the conventional structure, the tandem angular ball bearing can be handled by dividing it into two elements, the outer ring 5a and the inner ring side assembly 31. For this reason, if the inner ring side assembly 31 is assembled after being assembled by a bearing manufacturer and then shipped, it is easy to assemble the tandem angular ball bearing at the place of use at the assembly site of various rotary machine devices such as differential devices. Can do.

  Also in the case of the second example of such a conventional structure, as in the first example of the conventional structure, this tandem angular ball bearing is used as the inner peripheral surface of the support hole 22 of the support member 21 provided inside the differential case. And the outer peripheral surface of the pinion shaft 3, the outer ring 5 a is fitted into the support hole 22 by an interference fit, and the inner ring 6 a is fitted to the tip end portion of the pinion shaft 3 by an interference fit. The outer ring 5 a and the inner ring 6 a are combined through the balls 7.

  When the tandem angular ball bearing of the second example of the conventional structure is used, the inner ring 6a is held on both the large-diameter side and the small-diameter side before the inner ring 6a is fitted on the tip portion of the pinion shaft 3 by an interference fit. The inner ring side assembly 31 can be integrally handled together with the balls 8 and 9 and the balls 7. That is, even if the inner ring side assembly 31 is assembled, if the work of externally fitting the inner ring 6a to the pinion shaft 3 is performed by pressing the axial end surface of the inner ring 6a, the outer fitting work is accompanied. Indentations are not formed in the portions where the rolling surfaces of the balls 7 are in contact with each other on the large diameter side and small diameter side inner ring raceways 12 and 13. Therefore, it is possible to easily assemble the tandem angular ball bearing between the inner peripheral surface of the support hole 22 and the outer peripheral surface of the pinion shaft 3 without damaging the constituent members.

However, the tandem angular contact ball bearing of the second example of the conventional structure has the following problems to be solved.
The first problem is a problem caused by the absence of a groove shoulder in each of the axially one side portions of both the large diameter side and small diameter side outer ring raceways 10 and 11. For example, if this type of tandem angular ball bearing is used in combination with a device that supplies lubricating oil to the bearing only during operation, such as some differential gears, both the large-diameter and small-diameter outer rings are used when stopped. Lubricating oil does not remain in the lower end portions of the tracks 10, 11, and the lubricating oil flows out to the outside through axial one side portions of the lower end portions of both the large diameter side and small diameter side outer ring raceways 10, 11. . For this reason, there is a problem that it is difficult to improve the initial lubrication when the operation is resumed.

The second problem is caused by a state in which the plurality of balls 7 are exposed at the outermost portion in the radial direction of the inner ring side assembly 31 in a state where the inner ring side assembly 31 is assembled. That is, before assembling the tandem angular ball bearing, each ball 7 constituting the inner ring side assembly 31 is likely to collide with other articles during transportation, and the rolling surface of each ball 7 is damaged such as scratches. There is a problem that it is likely to occur.
Such a problem is also a problem that leads to a decrease in durability of the tandem angular ball bearing.

  Until now, many attempts have been made to improve the characteristics of tandem angular contact ball bearings, such as reduction of dynamic torque. However, in publicly known documents including Patent Documents 1 to 6, there is no description about a technique for preventing the rolling surface of each ball from being damaged when assembling the tandem angular ball bearing. In the current situation, the above-mentioned problems have not been sufficiently solved.

JP 11-48805 A JP 2004-169890 A JP 2004-183745 A JP 2009-138895 A JP 2002-523710A JP 2004-124996 A

In view of the circumstances as described above, the present invention, when assembled between the inner peripheral surface of a fixed portion such as a support portion provided inside a housing such as a differential case and the outer peripheral surface of the rotating shaft, Prevents damage such as scratches on the rolling surface of the ball from causing excessive life reduction, prevents excessive vibration and noise during operation, and has excellent durability An object of the present invention is to provide a tandem angular contact type ball bearing that can ensure high performance.
Further, the present invention aims to realize a structure in which a tandem angular ball bearing can be handled by being divided into two elements and a plurality of balls do not collide with other articles during the conveyance. is there.

The tandem angular ball bearing of the present invention basically has a large-diameter outer ring raceway having a relatively large diameter on one side in the axial direction of the inner peripheral surface, as in the case of conventionally known tandem angular ball bearings. Similarly, an outer ring having a relatively small diameter outer ring raceway on the other side in the axial direction, a large inner ring raceway having a relatively large diameter on one axial side of the outer peripheral surface, and a diameter on the other side in the same axial direction. Each of which has a relatively small small-diameter side inner ring raceway, an annular large-diameter side retainer having pockets at multiple circumferential positions, and pockets at multiple circumferential positions. An annular small-diameter side cage having a relatively small diameter, and the large-diameter side outer ring raceway and the large-diameter side inner ring raceway in a state of being held in each pocket of the large-diameter side cage. The large-diameter ball array A plurality of balls formed, and a small-diameter side ball that is rotatably provided between the small-diameter side outer ring raceway and the small-diameter side inner ring raceway while being held in each pocket of the small-diameter side cage. And a plurality of balls constituting a row. Further, contact angles in the same direction are given to the balls constituting the large-diameter side ball row and the balls constituting the small-diameter side ball row.

In particular, in the tandem angular contact ball bearing of the present invention, the outer ring includes groove shoulder portions on both axial sides of the large-diameter side outer ring raceway and axially other side portions of the small-diameter side outer ring raceway, respectively. It has.
At the same time, the inner ring is provided with a groove shoulder in each of one axial part of the large-diameter side inner ring raceway and one axial part of the small-diameter side inner ring raceway. The side portions and the other axial side portion of the small-diameter inner ring raceway are not provided with groove shoulders, respectively.
In addition, the large diameter side retainer and the small diameter side retainer are provided on the peripheral edge of the opening on the inner diameter side of each pocket over the entire circumference, thereby opening the inner diameter side of each pocket. The ball is prevented from coming out from the inside of each pocket to the inner diameter side in a state where the width is slightly smaller than the diameter of each ball and the balls are held in the pockets.
Further, each ball held in each pocket of the large-diameter side cage is in a state of being closest to the inner diameter side of the large-diameter side cage without elastically deforming the large-diameter side cage. The diameters of the circumscribed circles of these balls are larger than the inner diameters of the groove shoulder portions existing on both axial sides of the large-diameter side outer ring raceway.

In the present invention , preferably, the outer ring is provided with groove shoulders on both sides in the axial direction of the large diameter side outer ring raceway and on both sides in the axial direction of the small diameter side outer ring raceway .

Alternatively, the outer ring is configured not to include a groove shoulder on one axial side portion of the small-diameter side outer ring raceway . Further , the large-diameter side cage and the small-diameter side cage combine the outer ring , the large-diameter side cage, and the small-diameter side cage and the balls in the same positional relationship as a completed state as a ball bearing. In the state in which the outer ring side assembly is configured, the ends close to each other are provided with shapes facing each other in the axial direction.

A tandem angular ball bearing according to another invention deviating from the technical scope of the present invention includes an outer ring, an inner ring, and a plurality of balls in the same manner as a conventionally known tandem angular ball bearing. The outer ring is provided with two rows of outer ring raceways having different inner diameters on the inner peripheral surface, each of which is an angular type. Further, the inner ring is provided on the inner diameter side of the outer ring concentrically with the outer ring, and provided with two rows of inner ring raceways, each having an angular shape, having different outer diameters on the outer peripheral surface. Further, each of the balls rolls in a state where a contact angle in the same direction is given between both the inner ring raceways and the outer ring raceways for each row. It is provided freely.

In particular, a tandem angular contact ball bearing according to another invention is a continuous portion from an outer ring raceway having a small inner diameter to an end face having a larger inner diameter among both axial end surfaces of the outer ring, of the inner peripheral surface of the outer ring. And the entire part from the inner ring raceway with a large outer diameter to the continuous part with the end face with the smaller outer diameter among the axial end faces of the inner ring. The cross-sectional shape does not have a differentiable corner, that is, has no sharp corner, and is a polished smooth surface.

In the interpretation of the present invention, the inner peripheral surface of the outer ring is defined as the entire surface of the outer ring surface that can be seen from the inside in the radial direction. Therefore, not only the inner peripheral surface portion that is clearly directed radially inward, but also the inner peripheral surface of the outer ring not only with respect to the continuous portion having a circular arc cross section that exists between the inner peripheral surface portion and the axial end surface. include. In addition, this continuous part says from the boundary continuous with the said internal peripheral surface part to an outer peripheral part. Similarly, the outer peripheral surface of the inner ring is defined as the entire surface of the inner ring surface that can be seen from the outside in the radial direction, and not only the outer peripheral surface portion that is clearly directed radially outward, but also this outer peripheral surface. As for the continuous portion having an arc cross section existing between the portion and the axial end surface, the boundary from the boundary portion continuous with the outer peripheral surface portion to the inner peripheral edge portion of the continuous portion is included in the outer peripheral surface of the inner ring. To do.

The tandem angular contact ball bearing of the present invention rotatably supports, for example, a rotating shaft constituting a mechanical device incorporated in a power transmission system of an automobile, that is, a pinion shaft constituting a differential device or a transfer device, and the like. It can be suitably used for the purpose of supporting the radial and axial loads acting on the rotating shaft.

According to the tandem angular contact ball bearing of the present invention, the groove shoulders are provided on both axial sides of at least the large-diameter outer ring raceway among the large-diameter side or small-diameter side outer raceway. For this reason, for example, in a device in which lubricating oil is supplied to the bearing only during operation, as in some differential gears, when the tandem angular ball bearing of the present invention is used in combination, Of both outer ring raceways, the lubricating oil can remain in the lower end portion of the outer ring raceway where the groove shoulders exist on both axial sides. Therefore, it is possible to improve the initial lubrication in both rows when the operation is resumed. That is, when there are groove shoulders on both axial sides of both outer ring raceways, the state where the lubricating oil remains in the lower ends of both the large diameter side and small diameter side outer ring raceways when the operation is stopped. become. For this reason, when the operation is restarted, the initial lubrication of both rows can be made good by the lubricating oil accumulated at both lower ends. Further, only the large diameter side outer raceway, when groove shoulder portions in the axial direction on both sides is provided, when the stop of the operation, the as lubricating oil is accumulated only in the lower end of the large diameter side outer ring raceway state become. However, at the same time when the operation is resumed, a part of the lubricating oil collected at the lower end of the large-diameter outer ring raceway is pushed out by the balls rolling on the outer ring raceway and overflows to the outside. By entering, not only the row including the large-diameter side outer ring raceway but also the row including the small-diameter side outer ring raceway can improve the initial lubrication.

In addition , the outer ring, both the large-diameter side and small-diameter side cages, and the balls constituting both the large-diameter side and the small-diameter side ball rows are combined in the same state as when the assembly of the tandem angular ball bearing is completed. Therefore, it is possible to handle each of these parts integrally as an outer ring side assembly.
In this case, the tandem angular ball bearing can be handled by being divided into two components, that is, an outer ring side assembly and an inner ring. For this reason, if this outer ring side assembly is assembled and then shipped by a bearing manufacturer, etc., the assembly work of the tandem angular ball bearing of the present invention at the location of use is facilitated at the assembly site of various rotary machine devices such as differential devices. Can be done.
In particular, in the case of the present invention, the plurality of balls are arranged on the inner diameter side of the outer ring in a state where the outer ring side assembly is assembled. For this reason, it is possible to avoid the problem that each ball hits another article and is damaged during transportation before assembling the tandem angular ball bearing.
In carrying out the present invention, preferably, the hardness of each ball is set higher than the hardness of the race (at least the inner ring). The degree of increase is about 1 or more in terms of Rockwell hardness (HRc). Thus, if the hardness of the surface of each said ball | bowl is made high, damage to the surface of these each ball | bowl can be suppressed more reliably.

Moreover, according to the tandem angular ball bearing according to another invention as described above, the inner peripheral surface of the fixed portion such as a support portion provided in the housing such as the differential case, and the outer peripheral surface of the rotating shaft It is possible to prevent damage such as scratches from occurring on the rolling surface of each ball, which causes an excessive decrease in the service life. That is, in the tandem angular contact ball bearing according to another invention, when combining the outer ring that is internally fitted and fixed to the fixed portion and the inner ring that is fitted and fixed to the rotary shaft among the inner circumferential surface of the outer ring and the outer circumferential surface of the inner ring. In addition, the entire portion where the rolling surface of the ball may come into contact has no sharp corners and is a smooth surface. Therefore, even when the rolling surface of any of the balls hits any part of the inner peripheral surface of the outer ring or the outer peripheral surface of the inner ring or rubs strongly during the assembly operation, No damage such as scratches as described above occurs on the rolling surface of the ball. For this reason, during operation of a tandem angular ball bearing, it is possible to prevent excessive vibration and noise due to damage of the rolling surface of any ball, and to ensure sufficient durability of the tandem angular ball bearing I can do it.

The half part sectional view of the tandem angular ball bearing which shows the 1st example of the reference example about the present invention. Similarly, half sectional drawing for showing the part which should ensure the curvature radius of a cross-sectional shape among the internal peripheral surface of an outer ring | wheel, and the outer peripheral surface of an inner ring | wheel. Similarly, the half sectional view for showing the part which should make the surface smooth in the part which removed from the inner ring surface of the outer ring and the outer ring surface of the inner ring from the outer ring track and the inner ring track. Similarly, prior to internal fitting of the outer ring to the support portion, a half sectional view showing a state in which balls are assembled to the inner diameter side of the outer ring. Similarly, after the outer ring having a plurality of balls assembled on the inner diameter side is fitted and fixed to the support portion, a sectional view of a half showing the state in which the inner ring is fitted and fixed to the pinion shaft in advance on the inner diameter side of each of these balls. Sectional drawing of the tandem angular ball bearing which shows the 1st example of embodiment of this invention. Similarly, sectional drawing which shows some cages which hold | maintained the ball. Similarly, sectional drawing which shows the condition which assembles an outer ring side assembly. Similarly, sectional drawing which shows the situation which completes a tandem angular ball bearing by combining an outer ring side assembly and an inner ring. Sectional drawing of the tandem angular ball bearing which shows the 2nd example of embodiment of this invention. Similarly, sectional drawing which shows the condition which assembles an outer ring side assembly. Sectional drawing of the tandem angular ball bearing which shows the 2nd example of the reference example regarding this invention. Similarly, sectional drawing which shows the condition which assembles an outer ring side assembly. Sectional drawing of the tandem angular ball bearing which shows the 3rd example of embodiment of this invention. The half part sectional view which shows an example of the rotation support part of the pinion shaft which comprises the differential gear incorporating the tandem angular ball bearing of the conventional structure. Sectional drawing which shows another example of the tandem angular ball bearing of conventional structure. Similarly, sectional drawing which shows the condition which assembles an inner ring side assembly. Similarly, sectional drawing which shows the condition which combines an outer ring and an inner ring side assembly, and completes a tandem angular ball bearing.

[First example of reference example ]
FIGS. 1-5 has shown the 1st example of the reference example regarding this invention based on another invention . The ball bearing 1a of this reference example , which is a tandem angular ball bearing, includes an outer ring 5b, an inner ring 6b, a plurality of balls 7, and a pair of cages 8 and 9. The outer ring 5 b is provided with two rows of outer ring raceways 10, 11 having different inner diameters and each being an angular type on the inner peripheral surface. The inner ring 6b is disposed concentrically with the outer ring 5b on the inner diameter side of the outer ring 5b, and each of the outer peripheral surfaces facing the outer ring raceways 10 and 11 is an angular type and has an outer diameter. Two different inner ring raceways 12 and 13 are provided. During operation, a thrust load is applied between the outer ring 5b and the inner ring 6b in such a direction as to press the outer ring 5b to the left in FIG. 1 and the inner ring 6b to the right in the same manner. In a state of being incorporated in the differential gear, the side of the inner ring 6b whose outer peripheral surface has a large diameter becomes the input side, and a thrust load directed rightward in FIGS. 1 to 3 and 5 is applied to the inner ring 6b. On the other hand, the side of the outer ring 5b whose inner peripheral surface has a small diameter is the output side of this thrust load, and a leftward force in FIGS. 1 to 5 is applied to the outer ring 5b as a reaction force against this thrust load.

  The inner diameters of both outer ring raceways 10 and 11 are larger in the outer ring raceway 10 on the front side (left side in FIG. 1) of the reaction force acting on the outer ring 5b, and in the same way on the outer ring raceway 11 on the rear side (right side in FIG. 1). Is small. The outer diameters of the inner ring raceways 12 and 13 are larger in the inner ring raceway 12 on the rear side (left side in FIG. 1) of the thrust load acting on the inner ring 6b, and the inner ring raceway on the front side (right side in FIG. 1). 13 is smaller. Further, a plurality of balls 7 are provided between the outer ring raceways 10 and 11 and the inner ring raceways 12 and 13 in each row, and contact angles α and β in the same direction between the rows. It is provided so that it can roll freely. That is, the ball bearing 1a is a parallel combination type. The contact angles α and β may be the same or different from each other. Further, both the retainers 8 and 9 have different diameters, and each retains the balls 7 in both rows so as to roll freely. The basic structure of the ball bearing 1a is the same as that of the conventional tandem angular ball bearing 1 shown in FIG.

In particular, in the case of the ball bearing 1a of the present reference example , the inner ring surface of the outer ring 5b, the outer ring raceway 11 having a small inner diameter, and the end face 23 on the side having the larger inner diameter among the axial end faces of the outer ring 5b; The entire portion up to the continuous portion has no corner portion that cannot be differentiated with respect to the cross-sectional shape, that is, has no sharp corner portion, and is a smooth surface that is smoothly continuous and polished. Further, the entire portion of the outer ring surface of the inner ring 6b from the inner ring raceway 12 having a large outer diameter to the continuous part with the end surface 24 on the side having the smaller outer diameter of both end surfaces in the axial direction of the inner ring 6b has a cross-sectional shape. With respect to the surface, there is no non-differentiable corner, and the surface is smoothly continuous and polished. Note that the end faces 23 and 24 themselves do not necessarily have to be smooth surfaces, but they can be made smooth. However, the corner portions 25a and 25g, which are continuous portions between the both end surfaces 23 and 24 and the inner peripheral surface of the outer ring 5b or the outer peripheral surface of the inner ring 6b, are smooth surfaces.

The above point will be described in more detail with reference to FIGS. Of the inner peripheral surface of the outer ring 5b, both outer ring raceways 10 and 11 and among the outer peripheral surface of the inner ring 6b, both inner ring raceways 12 and 13 are conventionally polished with a rotating grindstone to form smooth surfaces. In this reference example , not only this part, but also the conventional structure, the rough surface and the sharp corners were left as they were without any special processing such as polishing. Of these, the portions other than the portions of the tracks 10 to 13 are polished to form a smooth surface.

  For example, a total of nine corners 25a to 25i of the six positions on the inner peripheral surface of the outer ring 5b and the three positions on the outer peripheral surface of the inner ring 6b, shown by the dotted circles in FIG. Of these, the corners 25c, 25d, 25f, 25h, and 25i existing at the side edge portions of the tracks 10, 11, and 13 are polished unless special processing is performed. The edge shape formed at the time (the tip having a non-differentiable cross-sectional shape) is left as it is. In addition, the remaining corner portions 25a, 25b, 25e, and 25g also retain the edge shape formed when the adjacent surfaces are cut. In short, unless special processing is performed, in any corner portion 25a to 25i, a cross-sectional shape that cannot be differentiated, that is, a single tangent cannot be set with respect to a certain point, and the radius of curvature of the cross-sectional shape is almost equal. A sharp shape of 0 is left as it is.

  In addition, the inclined surface portions 26a to 26d at a total of four positions, each of the two positions of the inner peripheral surface of the outer ring 5b and the outer peripheral surface of the inner ring 6b, as shown by the chain line ellipses in FIG. As for the two cylindrical surface portions 27a and 27b continuous from the large diameter side, the cut surface and the heat-treated skin are left as they are unless special processing is performed. Such a rough surface tends to cause damage to the rolling surface of the ball 7 when the ball bearing 1 is assembled.

In the case of the present reference example , the outer peripheral surface of the outer ring 5b and the outer peripheral surface of the inner ring 6b are polished to the portions other than both the outer ring raceways 10 and 11 and the both inner ring raceways 12 and 13, and the inclined surface portions 26a to 26d. And each cylindrical surface part 27a, 27b is made into the smooth surface. That is, the surface roughness of each of the inclined surface portions 26a to 26d and the cylindrical surface portions 27a and 27b is a smooth surface having an arithmetic average roughness (Ra) of about 0.4 μm. The surface roughness of each of the inclined surface portions 26a to 26d and the cylindrical surface portions 27a and 27b is about 0.4 μm Ra as described above in consideration of polishing simultaneously with the respective tracks 10 to 13 as will be described later. It is said. However, even if Ra is about 0.6 μm, and further Ra is about 0.8 μm, there is no problem in terms of preventing damage to the rolling surface of the ball 7. A smaller surface roughness value is preferable from the viewpoint of preventing damage to the rolling surface of the balls 7 and obtaining good quality tracks 10 to 13, but even if it is excessively small, the processing cost only increases. In consideration of the processing cost, it is not realistic to make the surface roughness Ra smaller than 0.2 μm.

  If each inclined surface part 26a-26d and both cylindrical surface parts 27a, 27b are made into the above smooth surfaces, these each surface parts 26a-26d, 27a, 27b and the rolling surface of each ball 7 rubbed somewhat strongly. Even so, the rolling surface of each ball 7 is not damaged so as to cause an excessive decrease in life. The surface roughness of each of the surface portions 26a to 26d, 27a, and 27b is the same as the surface roughness of each of the tracks 10 to 13 before super finishing, which will be described later. preferable. This reason will be described later.

  Further, among the inner peripheral surface of the outer ring 5b, the corners 25a to 25f existing between the surfaces existing from the end surface 23 to the outer ring raceway 11 on the small diameter side, and the outer peripheral surface of the inner ring 6b. The corner portions 25g to 25i existing in the portion from the end surface 24 to the inclined surface portion 26d are convex curved surfaces having a curvature radius of a cross-sectional shape of 0.2 mm or more by polishing, and each of the surface portions 26a to 26d, The smooth surface is equivalent to 27a and 27b. The upper limit value of the radius of curvature related to the cross-sectional shape of each corner 25a to 25i is not particularly limited. The larger the radius of curvature, the more advantageous in terms of preventing damage to the rolling surface of each ball 7. However, even if it is increased, no further damage prevention effect can be expected, and it is adjacent to the raceway surface. The corner portions 25c, 25d, 25f, 25h, and 25i are adversely affected by the holding function of the balls 7 and the securing of the width dimension of the rolling surface. Therefore, the maximum value of the radius of curvature is restricted by design considerations in consideration of these points and, in some cases, the shape and material of the cages 8 and 9. In the case of a tandem angular ball bearing for supporting a pinion shaft of a differential gear or a transfer device, it is not preferable to increase the radius of curvature to a level exceeding 1 mm. In addition, the cross-sectional shape of each corner | angular part 25a-25i may be a single circular arc, or the complex circular arc which carried out the smooth continuous by combining several circular arcs from which a curvature radius mutually differs. In this case, the curvature radius of the arc portion having the smallest curvature radius is set to 0.2 mm or more.

  In addition to increasing the radius of curvature of the cross-sectional shape of each corner 25a to 25i, the work to make the shape and properties (surface roughness) of the inner peripheral surface of the outer ring 5b and the outer peripheral surface of the inner ring 6b as described above, It is preferable to use a so-called rotary grindstone that has a bus bar shape that matches the bus bar shape of the peripheral surface to be machined. The reason for this is that not only can the shape and properties of the peripheral surface be processed at once, but the processing efficiency is not only good, but also the peripheral portion is divided in the width direction and processed with separate grindstones. This is to eliminate the possibility of the occurrence of sharp steps on the surface. For these reasons, it is preferable to finish the peripheral surfaces with a general-purpose rotary grindstone. However, in the case of a general-purpose rotary grindstone, it is realistic to have the same properties over the entire width. For this reason, the surface roughness of the inclined surfaces 26a to 26d is preferably the same as the surface roughness of the tracks 10 to 13. In addition, even with respect to the cylindrical surface portions 27a and 27b existing in the portion between the corner portions 25b and 25c and the portion between the corner portions 25e and 25f, the entire surface is processed with a rotary grindstone to obtain a similar smooth surface. . This is because both cylindrical surface portions 27a and 27b also rub against the rolling surface of each ball 7 when the ball bearing 1a is assembled.

Further, as described above, each of the tracks 10 to 12 is subjected to superfinishing after making the surface roughness Ra a smooth surface of about 0.4 μm. Along with this super-finishing process, a very slight bent portion is formed with respect to the cross-sectional shape at the boundary between each track 10-12 and the portion adjacent to each track 10-12. There is a possibility that the generatrix of the portion adjacent to 10 to 12 does not completely exist in the tangential direction with respect to the arc of the cross-sectional shape of each of the tracks 10 to 12. However, the bending angle of such a bent portion, that is, the deviation of the direction of the generatrix with respect to the complete tangential direction is extremely small, and the bent portion causes excessive life reduction on the rolling surface of each ball 7. There will be no damage such as scratches. Therefore, the bent portion generated by such super finishing is not treated as a non-differentiable corner portion in the interpretation of another invention .

As described above, the tandem angular ball bearing 1a of the present reference example is provided between the inner peripheral surface of the support hole 22a provided in the support portion 21a provided in the differential case and the outer peripheral surface of the pinion shaft 3a ( As shown in FIG. 4, first, as shown in FIG. 4, in a state where the balls 7 in both rows are held by the cages 8 and 9, respectively, a double row is provided on the inner peripheral surface of the outer ring 5b. The outer ring raceways 10 and 11 are assembled on the inner diameter side. The inner diameters of the cylindrical surface portions 27a and 27b adjacent to the outer ring raceways 10 and 11 are slightly smaller than the inner diameters of the bottom portions (the portions with the largest inner diameters) of the outer ring raceways 10 and 11. Therefore, the balls 7 held by the cages 8 and 9 are elastically deformed by the cages 8 and 9 to reduce the diameter of the circumscribed circle of the balls 7, and the edge on the large diameter side. Pass through the department. After passing, the diameter of the circumscribed circle of each ball 7 is expanded by elastic restoration of both the cages 8, 9, and a part of the rolling surface of each ball 7 is elastically applied to both outer ring raceways 10, 11. Make contact. As a result, as shown in the upper right part of FIG. 5, each ball 7 is assembled to the inner diameter side of the outer ring 5 b via both the cages 8 and 9 so as not to be inadvertently separated. Accordingly, the inner diameters of both cylindrical surface portions 27a and 27b are determined by the material, thickness, shape, dimensions, etc., taking into account the amount of elastic deformation of both cages 8 and 9, etc., and ease of assembly and non-separability after assembly. Designed to be compatible with both.

  In any case, during the assembling work as described above, each ball 7 may hit or rub against the corners 25a to 25f and the inclined portions 26a and 26b existing on the inner peripheral surface of the outer ring 5b. . However, each of these corners 25a to 25f is a convex curved surface having a radius of curvature of 0.2 mm or more, and both inclined portions 26a and 26b and both cylindrical surface portions 27a and 27b are smooth surfaces. The moving surface is not damaged to the extent that it causes an excessive decrease in life. In this manner, the operation of assembling these balls 7 on the inner diameter side of the outer ring 5b can be performed at a bearing manufacturing factory.

  As described above, the outer ring 5b in which the balls 7 are assembled on the inner diameter side is transported to a differential gear assembly factory, and, as shown in the upper right portion of FIG. Since this inner fitting fixing work can be performed by pressing the end surface 23 on the large diameter side of the outer ring 5b, the rolling surfaces of the balls 7 are not strongly pressed against the outer ring raceways 10 and 11, and both the outer ring raceways are provided. Brinell indentations are not formed on 10 and 11.

  In this way, when the outer ring 5b is fitted and fixed to the inner diameter side of the support hole 22a, the inner ring 6b is then inserted into the inner diameter side of each ball 7 held on the inner diameter side of the outer ring 5b. Prior to this insertion operation, the inner ring 6b is externally fixed to the pinion shaft 3a by an interference fit as shown in the lower left part of FIG. In this way, when the inner ring 6b is inserted into the inner diameter side of each ball 7 as shown by a thick arrow in FIG. 5, each of the balls 7 has a corner portion 25g to 25i or an inclination that exists on the outer peripheral surface of the inner ring 6b. There is a possibility of hitting or rubbing against the surface portions 26c and 26d. However, since each of the corner portions 25g to 25i is a convex curved surface having a radius of curvature of 0.2 mm or more, and the both inclined surface portions 26c and 26d are smooth surfaces, the rolling surface of each ball 7 is It will not be damaged to the extent that it will cause excessive life reduction.

As a result, when the ball bearing 1a of the present reference example , which is a tandem angular ball bearing, is assembled between the support portion 21a and the pinion shaft 3a, the rolling contact surface of each ball 7 causes excessive life reduction. It is possible to prevent the occurrence of damage such as scratches. Therefore, during operation of a differential gear or the like incorporating the ball bearing 1a, excessive vibration and noise are not generated due to damage of the rolling surface of any of the balls 7, and the ball bearing 1a and The durability of a device such as a differential gear incorporating this can be sufficiently secured.

[ First example of embodiment]
6 to 9 show a first example of an embodiment according to the present invention . The tandem angular ball bearing of this example includes an outer ring 5c, an inner ring 6c, both large-diameter and small-diameter side cages 8a and 9a, and a plurality of balls 7 constituting both large-diameter and small-diameter side ball arrays. Is provided. The outer ring 5c is provided with double-row angular type large-diameter and small-diameter both outer ring raceways 10 and 11 having different inner diameters on the inner peripheral surface. Further, the inner ring 6c has double-row angular type large-diameter and small-diameter inner ring raceways 12 and 13 having different outer diameters on the outer peripheral surface. The large-diameter side and small-diameter side cages 8a and 9a are all formed in an annular shape and have pockets 14a and 15a at a plurality of locations at equal intervals in the circumferential direction. Further, each ball 7 constituting the large diameter side ball row is held between each large diameter side outer ring raceway 10 and the large diameter side inner ring raceway 12 while being held in each pocket 14a of the large diameter side cage 8a. It is provided to roll freely. Further, each ball 7 constituting the small diameter side ball train is rollable between the small diameter side outer ring raceway 11 and the small diameter side inner ring raceway 13 while being held in each pocket 15a of the small diameter side retainer 9a. Is provided. In this state, contact angles in the same direction (parallel combination type) are given to the balls 7 constituting the large diameter side ball row and the balls 7 constituting the small diameter side ball row. The contact angles θ ₁ and θ ₂ of these two rows can be the same (θ ₁ = θ ₂ ) or different (θ ₁ ≠ θ ₂ ). The basic configuration of the tandem angular ball bearing described above is the same as that of the conventional structure.

  In particular, in the case of this example, the outer ring 5c is provided with groove shoulders 16a, 16b, 17a, and 17b on both sides in the axial direction of both the large diameter side and small diameter side outer ring raceways 10 and 11, respectively. On the other hand, the inner ring 6c is one side in the axial direction of both the large-diameter side and small-diameter side inner ring raceways 12 and 13 ("one side" with respect to the axial direction refers to the left side of FIGS. 6 and 8-13. The groove shoulders 18a and 19a are provided only on the right side of FIGS. 6 and 8 to 13 on the other side in the axial direction, and no groove shoulder is provided on the other side in the axial direction. Further, both the large-diameter side and small-diameter side cages 8a and 9a hold the balls 7 in the pockets 14a and 15a, and the balls 7 come out from the pockets 14a and 15a to at least the inner diameter side. It has a structure that can prevent things. Specifically, as shown in detail in FIG. 7, the opening width (opening diameter) W on the inner diameter side of each pocket 14a (15a) of both the large diameter side and small diameter side retainers 8a (9a) 7 slightly smaller than the diameter D (W <D). As a result, the engagement margin 32 having a width dimension of slightly less than (D−W) / 2 (“weak” is due to the pocket gap) is formed around the periphery of the opening peripheral edge of each pocket 14a (15a) on the inner diameter side. Is provided.

  When assembling the tandem angular ball bearing of this example configured as described above, first, an outer ring side assembly 33 as shown by a solid line in FIG. 8 is assembled. For this purpose, first, each ball 7 is held in each pocket 14a, 15a of both the large-diameter side and small-diameter side retainers 8a, 9a as indicated by the chain line in FIG. The balls 7 held in the pockets 14a of the large-diameter side cage 8a are placed on the inner diameter side of the large-diameter side cage 8a without elastically deforming the large-diameter side cage 8a. The diameter of the circumscribed circle of each of the balls 7 in the close state is larger than at least the inner diameters of the groove shoulder portions 16 a and 16 b existing on both axial sides of the large-diameter outer ring raceway 10. Further, each ball 7 held in each pocket 15a of the small-diameter side retainer 9a is brought close to the inner diameter side of the small-diameter side retainer 9a without elastically deforming the small-diameter side retainer 9a. The diameter of the circumscribed circle of each ball 7 is at least larger than the inner diameters of the groove shoulder portions 17a and 17b existing on both axial sides of the small-diameter outer ring raceway 11.

  In any case, if the balls 7 are held in the pockets 14a and 15a of both the large-diameter side and small-diameter side cages 8a and 9a as described above, then as shown by the arrows in FIG. The balls 7 held by the large-diameter side and small-diameter side cages 8a and 9a are inserted into the inner diameter side of the outer ring 5c from one axial side of the outer ring 5c. As a result, as shown by the solid line in the figure, the balls 7 held by the large-diameter side and small-diameter side cages 8a and 9a are assembled to the inner diameter side of the large-diameter side and small-diameter side outer ring raceways 10 and 11, respectively. . At this time, the balls 7 held by the large-diameter side and small-diameter side cages 8a and 9a are elastically deformed by the large-diameter side and small-diameter side cages 8a and 9a. It passes through each groove shoulder 16a, 16b, 17a while reducing the diameter of the circle. Then, after passing, the diameter of the circumscribed circle of each ball 7 is expanded by elastic restoration of both the large diameter side and small diameter side cages 8a, 9a, and each ball 7 has a large diameter side, a small diameter side outer ring raceway 10, 11 is assembled to the inner diameter side.

  In the state where the outer ring side assembly 33 is completed in this manner, the balls 7 held by both the large diameter side and small diameter side cages 8a and 9a are respectively connected to the large diameter side and small diameter side cages 8a and 9a. Are prevented from coming out from the inside of each pocket 14a, 15a to the inner diameter side, and coming out in the axial direction from the inside of both the large diameter side and small diameter side outer ring raceways 10, 11, respectively, the groove shoulder portions 16a, 16b. , 17a, 17b. For this reason, the outer ring 5c, the large-diameter side and small-diameter side cages 8a, 9a, and the balls 7 can be handled integrally (in a non-separated state) as the outer ring-side assembly 33. If such an outer ring side assembly 33 is assembled, then, as indicated by an arrow in FIG. 9, the inner ring 6 c is connected to the inner diameter side of the outer ring side assembly 33 from one axial direction of the outer ring side assembly 33. insert. As a result, as shown in FIG. 6, the balls 7 held by the large-diameter side and small-diameter side cages 8a and 9a are assembled on the outer-diameter side of the large-diameter side and small-diameter side inner ring raceways 12 and 13, respectively. To complete the assembly of the tandem angular contact ball bearing. In the case of this example, there are no groove shoulders on the other axial portions of the large-diameter side and small-diameter side inner ring raceways 12 and 13, respectively. Therefore, the insertion work of the inner ring 6c as described above is smoothly performed. Yes.

  According to the tandem angular ball bearing of this example configured as described above, this tandem angular ball bearing can be handled by dividing it into two elements, the outer ring side assembly 33 and the inner ring 6c. For this reason, if the outer ring side assembly 33 is assembled by a bearing manufacturer and then shipped, the operation of assembling the tandem angular ball bearing at the place of use can be easily performed at the assembly site of various rotary machine devices such as a differential device.

  For example, when the tandem angular ball bearing of this example is used as a rolling bearing that supports a portion near the tip (pinion gear) of the pinion shaft constituting the differential device, the outer ring side assembly 33 is assembled, The outer ring 5c is fitted into the support hole 22 provided in the differential case by an interference fit, and the inner ring 6c is fitted to the portion near the tip of the pinion shaft 3 by an interference fit. In this case, the outer ring 5c can be fitted into the support hole 22 with an interference fit by pressing the axial end surface of the outer ring 5c. For this reason, an indentation is not formed in the part where each ball 7 is contacting among both large diameter side and small diameter side outer ring raceways 10 and 11 with this internal fitting operation. Thereafter, by inserting the inner ring 6c into the inner diameter side of the outer ring side assembly 33 as shown in FIG. 9 described above, the tandem angular ball bearing of this example is inserted between the support hole 22 and the pinion shaft 3, Can be assembled easily.

  Further, in the case of the tandem angular ball bearing of this example, groove shoulder portions 16a, 16b, 17a, and 17b are provided on both sides in the axial direction of both the large diameter side and small diameter side outer ring raceways 10 and 11, respectively. For this reason, for example, when using the tandem angular ball bearing of this example in a device that supplies lubricating oil to the bearing only during operation, such as some differential devices, when the operation is stopped, Lubricating oil can remain in the lower end portions of both the large-diameter side and small-diameter side outer ring raceways 10 and 11. For this reason, when the operation is resumed, the initial lubrication in both rows can be made good by the lubricating oil accumulated at both lower ends.

Even when the structure of this example is implemented, it is preferable that the outer ring with the smaller inner diameter is formed on the inner peripheral surface of the outer ring 5c, as in the case of the first example of the reference example shown in FIGS. The entire portion from the raceway 11 to the continuous portion with the end surface 23 on the side with the larger inner diameter of both end surfaces in the axial direction of the outer ring 5c is smoothly continuous and polished without sharp corners. A smooth surface is used (implemented in accordance with the aspect of another invention ). Further, of the outer peripheral surface of the inner ring 6c, the entire portion from the inner ring raceway 12 having a large outer diameter to the continuous part with the end surface 24 on the side having a smaller outer diameter is smoothly continuously polished and polished. To do. The properties of both end surfaces 23 and 24 and the properties of the corners that are continuous portions of the both end surfaces 23 and 24 and the inner peripheral surface of the outer ring 5c or the outer peripheral surface of the inner ring 6c are the same as in the first example of the reference example . To. If such a configuration is adopted, in addition to the operations and effects of this example described above, damage such as scratches may occur on the rolling surface of each ball 7 during the assembly work of the tandem angular ball bearing of this example. The durability of the tandem angular ball bearing and the rotating machine device incorporating the same can be sufficiently secured.

[ Second Example of Embodiment]
10-11 has shown the 2nd example of embodiment of this invention based on this invention. In the case of this example, the shapes of the outer ring 5d and the large diameter side cage 8b are different from those of the first example of the above-described embodiment . That is, the outer ring 5d is provided with groove shoulders 16a, 16b, and 17b only on both sides in the axial direction of the large-diameter side outer ring raceway 10 and on the other side in the axial direction of the small-diameter side outer ring raceway 11, respectively. A groove shoulder portion is not provided on one side portion of the side outer ring raceway 11 in the axial direction. The large-diameter side cage 8b is formed with an inward flange-like flange 34 at the other axial end, and the outer surface of the flange 34 is axially one end surface of the small-diameter side cage 9a in the axial direction. They are facing each other.

  When assembling the tandem angular ball bearing of this example as described above, first, an outer ring side assembly 33a as shown by a solid line in FIG. 11 is assembled. For this purpose, first, as indicated by a chain line in the figure, each ball 7 is held in each pocket 14a, 15a of both the large diameter side and small diameter side retainers 8b, 9a. Next, as indicated by arrows in the figure, the balls 7 held by both the large-diameter side and small-diameter side cages 8b and 9a are inserted into the inner diameter side of the outer ring 5d from one axial side of the outer ring 5d. . As a result, as shown by the solid line in the figure, the balls 7 held by the large diameter side and small diameter side cages 8b and 9a are assembled to the inner diameter side of the large diameter side and small diameter side outer ring raceways 10 and 11, respectively. . At this time, each ball 7 held by the small diameter side cage 9a can be smoothly inserted into the inner diameter side of the small diameter side outer ring raceway 11 regardless of the existence of the respective groove shoulder portions 16a, 16b. On the other hand, each ball 7 held by the large-diameter side cage 8b elastically deforms the large-diameter side cage 8b to reduce the diameter of the circumscribed circle of each ball 7, and the groove shoulder portion 16a. Pass through. After the passage, the diameter of the circumscribed circle of each ball 7 is expanded by the elastic restoration of the large-diameter side cage 8b, and the respective balls 7 are assembled on the inner diameter side of the large-diameter outer ring raceway 10.

  In the state where the outer ring side assembly 33a is completed in this way, the balls 7 held by the large diameter side and small diameter side cages 8b and 9a are respectively connected to the large diameter side and small diameter side cages 8b and 9a. Are prevented from coming out from the inside of each pocket 14a, 15a to the inner diameter side. Further, each ball 7 held by the large-diameter side cage 8b slips out from the inside of the large-diameter side outer ring raceway 10 in the axial direction. It is blocked by 16a and 16b. Further, each ball 7 held by the small-diameter side retainer 9a is pulled out from the inside of the small-diameter side outer ring raceway 11 to one side in the axial direction. It is prevented by coming into contact (engagement) with the outer surface of the flange 34, and is also prevented from coming out to the other side in the axial direction by the groove shoulder 17b existing on the other side in the axial direction of the small-diameter outer ring raceway 11. Is done. Therefore, the outer ring 5d, the large-diameter side and small-diameter side cages 8b and 9a, and the balls 7 can be integrally handled as the outer ring-side assembly 33a. After such an outer ring side assembly 33a is assembled, the inner ring 6c is then inserted into the inner diameter side of the outer ring side assembly 33a from one axial direction of the outer ring side assembly 33a. As a result, as shown in FIG. 10, the balls 7 held by both the large-diameter side and small-diameter side cages 8b and 9a are assembled on the outer-diameter side of both the large-diameter side and small-diameter side inner ring raceways 12 and 13. To complete the assembly of the tandem angular contact ball bearing.

  Also in the case of the tandem angular ball bearing of this example configured as described above, this tandem angular ball bearing can be handled by dividing it into two elements, the outer ring side assembly 33a and the inner ring 6c. For this reason, if the outer ring side assembly 33a is assembled after being assembled by a bearing manufacturer and then shipped, the operation of assembling the tandem angular ball bearing at the use location can be easily performed at the assembly site of various rotary machine devices such as a differential device.

Further, in the case of the tandem angular ball bearing of this example, groove shoulder portions 16 a and 16 b are provided on both axial sides of the large-diameter side outer ring raceway 10, respectively. For this reason, for example, when using the tandem angular ball bearing of this example in a device that supplies lubricating oil to the bearing only during operation, such as some differential devices, when the operation is stopped, Lubricating oil can remain in the lower end portion of the large-diameter side outer ring raceway 10. Therefore, the initial lubrication of both rows when the operation is resumed becomes good. That is, with respect to the row including the large-diameter side outer ring raceway 10, the initial lubrication of the row can be satisfactorily performed by the lubricating oil accumulated at the lower end portion of the large-diameter side outer ring raceway 10. On the other hand, with respect to the row including the small-diameter side outer ring raceway 11, at the same time when the operation is resumed, a part of the lubricating oil accumulated at the lower end of the large-diameter side outer ring raceway 10 rolls on the large-diameter side outer ring raceway 10 part. It is pushed by the balls 7 and overflows to the outside, and this enters the small diameter side outer ring raceway 11, whereby the initial lubrication of the row becomes good. Other configurations and operations are basically the same as those in the first example of the above-described embodiment, including preferably that the inner peripheral surface of the outer ring 5d and the outer peripheral surface of the inner ring 6c are smooth surfaces. It is.

  In particular, in the case of the structure of this example, the balls 7 held by both the large-diameter side and small-diameter side cages 8b and 9a are assembled on the inner diameter side of both the large-diameter side and small-diameter side outer ring raceways 10 and 11. At this time, each ball 7 held by the large-diameter side cage 8b only needs to come into contact with the groove shoulder 16a, which is advantageous from the viewpoint of preventing damage to each ball 7. In addition, since the flange portion 34 is formed in the large-diameter side retainer 8b, the assembly of the outer ring-side assembly 33a can be performed without forming a groove shoulder in one axial portion of the small-diameter outer ring raceway 11. In this state, it is possible to effectively prevent the balls 7 held by the small diameter side cage 9a from slipping out from the inside of the small diameter side outer ring raceway 11 to one side in the axial direction. Therefore, in the case of the structure of this example, after assembling the ball bearing as shown in FIG. 10, the inner ring 6c can be smoothly pulled out to the left side (one side in the axial direction). The outer ring side assembly 33a can be prevented from being scattered.

[ Second example of reference example ]
12-13 has shown the 2nd example of the reference example regarding this invention . In the case of this reference example , the outer ring 5e and the shape of a part of both the large diameter side and small diameter side cages 8c, 9c are different from those of the first example of the embodiment shown in FIGS. . That is, the outer ring 5e is provided with groove shoulders 16b, 17a, and 17b only on the other axial side portion of the large-diameter side outer ring raceway 10 and on both axial sides of the small-diameter side outer ring raceway 11, respectively. A groove shoulder portion is not provided on one side portion of the side outer ring raceway 10 in the axial direction. Further, the large-diameter side cage 8c is provided with an inward engagement portion 35 at the other end in the axial direction of the inner peripheral surface over the entire circumference. Further, the small-diameter side retainer 9c is provided with an outward engagement portion 36 over the entire circumference at one end portion in the axial direction of the outer peripheral surface. The outward engagement portion 36 and the inward engagement portion 35 are engaged with each other with the inner surfaces of the engagement portions 35 and 36 facing each other.

When assembling the tandem angular ball bearing of this reference example as described above, first, an outer ring side assembly 33b as shown by a solid line in FIG. 13 is assembled. For this purpose, first, as shown by the chain line in the figure, in the state where the inward engagement portion 35 of the large diameter side retainer 8c and the outward engagement portion 36 of the small diameter side retainer 9c are engaged, Each ball 7 is held in each pocket 14a, 15a of both the large diameter side and small diameter side cages 8c, 9c. Next, as indicated by arrows in the figure, the balls 7 held by both the large-diameter side and small-diameter side cages 8c and 9c are inserted into the inner diameter side of the outer ring 5e from one side in the axial direction of the outer ring 5e. . As a result, as shown by the solid line in the figure, the balls 7 held by the large-diameter side and small-diameter side cages 8c and 9c are assembled to the inner diameter side of the large-diameter side and small-diameter side outer ring raceways 10 and 11, respectively. . At this time, each ball 7 held by the small diameter side cage 9c passes through the groove shoulder portion 17a while elastically deforming the small diameter side cage 9c and reducing the diameter of the circumscribed circle of each ball 7. . Then, after passing, the diameter of the circumscribed circle of each ball 7 is expanded by the elastic restoration of the small-diameter side cage 9 c, and each of these balls 7 is assembled on the inner diameter side of the small-diameter side outer ring raceway 11. On the other hand, each ball 7 held by the large diameter side cage 8 c can be smoothly inserted into the inner diameter side of the large diameter side outer ring raceway 10.

  In the state where the outer ring side assembly 33b is completed in this manner, the balls 7 held by both the large diameter side and small diameter side cages 8c and 9c are the large diameter side and small diameter side cages 8c and 9c. Are prevented from coming out from the inside of each pocket 14a, 15a to the inner diameter side. Further, the balls 7 held by the small-diameter side retainer 9c slip out in the axial direction from the inside of the small-diameter side outer ring raceway 11, so that the groove shoulder portions 17a, 17b existing on both axial sides of the small-diameter side outer ring raceway 11 are provided. Is prevented by. Further, each ball 7 held by the large-diameter side cage 8c is pulled out from the inside of the large-diameter side outer ring raceway 10 to one side in the axial direction. The groove shoulder 16b existing on the other side in the axial direction of the large-diameter outer ring raceway 10 is prevented from being engaged with the outward engagement portion 36 of the container 9c, and also coming out to the other side in the axial direction. Is prevented by. Therefore, the outer ring 5e, both the large diameter side and small diameter side cages 8c and 9c, and the balls 7 can be integrally handled as the outer ring side assembly 33b. When such an outer ring side assembly 33b is assembled, the inner ring 6a is then inserted into the inner diameter side of the outer ring side assembly 33b from one axial direction of the outer ring side assembly 33b. Thus, as shown in FIG. 12, the balls 7 held by the large-diameter side and small-diameter side cages 8c and 9c are assembled to the outer-diameter side of the large-diameter side and small-diameter side inner ring raceways 10 and 11, respectively. To complete the assembly of the tandem angular contact ball bearing.

Also in the case of the tandem angular ball bearing of this reference example configured as described above, this tandem angular ball bearing can be handled by dividing it into two elements, the outer ring side assembly 33b and the inner ring 6a. For this reason, if the outer ring side assembly 33b is assembled after being assembled by a bearing manufacturer and then shipped, the operation of assembling the tandem angular ball bearing at the use location can be easily performed at the assembly site of various rotary machine devices such as a differential device.

In the case of the tandem angular ball bearing of this reference example , groove shoulder portions 17a and 17b are provided on both axial sides of the small-diameter outer ring raceway 11, respectively. For this reason, for example, when using the tandem angular ball bearing of this example in a device that supplies lubricating oil to the bearing only during operation, such as some differential devices, when the operation is stopped, Lubricating oil can remain in the lower end portion of the small-diameter side outer ring raceway 11. Therefore, the initial lubrication of both rows when the operation is resumed becomes good. That is, with respect to the row including the small-diameter side outer ring raceway 11, the initial lubricating of the row can be improved by the lubricating oil accumulated at the lower end portion of the small-diameter side outer ring raceway 11. On the other hand, with respect to the row including the large-diameter side outer ring raceway 10, at the same time when the operation is resumed, a part of the lubricating oil accumulated in the lower end portion of the small-diameter side outer ring raceway 11 rolls on the small-diameter side outer ring raceway 11 7 is pushed out and overflows to the outside, and this enters the large-diameter outer ring raceway 10, whereby the initial lubrication of the row becomes good. Other configurations and operations are preferably the same as those of the first example of the embodiment shown in FIGS. 6 to 9 described above, including making the inner peripheral surface of the outer ring 5e and the outer peripheral surface of the inner ring 6a smooth. Same as the case.

In each of the above-described embodiments and reference examples , as the large-diameter side and small-diameter side both-side cages, the main body portion, that is, the portion that holds each ball has a cylindrical shape. However, when carrying out the present invention, as the large-diameter side and small-diameter side retainers, those having a non-cylindrical shape of the main body portion, for example, a partially conical cylindrical shape can also be employed.

[ Third example of embodiment]
FIG. 14 shows a third example of an embodiment of the present invention according to the present invention and another invention . In the case of this example, between the pair of outer ring raceways 10 and 11 on the inner circumferential surface of the outer ring 5d in the axial direction, and between the pair of inner ring raceways 12 and 13 on the outer circumferential surface of the inner ring 6c in the axial direction intermediate portion. Locking grooves 37a and 37b are formed in the part over the entire circumference. These locking grooves 37a and 37b are used when the outer ring 5d is extracted from the inner diameter side of the support portion 21a (see FIG. 5) or when the inner ring 6c is extracted from the periphery of the pinion shaft 3a (see FIG. 5). Used to lock the tip of the extraction jig. The locking grooves 37a and 37b are formed in a portion that has a rectangular cross-sectional shape and does not interfere with the cages 8b and 9a in order to easily lock the tip of the extraction jig. Generally, when the outer ring 5d is extracted from the inner diameter side of the support portion 21a, the distal end portion of the extraction jig is locked to the shoulder portion of the end portion on the small diameter side of the inner peripheral surface of the outer ring 5d. . Further, when the inner ring 6c is extracted from the periphery of the pinion shaft 3a, the tip of the extraction jig is locked to the shoulder of the outer diameter side end of the inner ring 6c. However, if a limit design such as increasing the diameter of the balls 7 or 7 is performed in order to secure the load capacity, the axial thickness of the shoulders may be reduced, and the shoulders may be damaged. There is. In such a case, one or both of the locking grooves 37a and 37b may be provided.

In the case of this example, the locking grooves 37a and 37b as described above are provided, and both side edges of the opening portions of both the locking grooves 37a and 37b, that is, inside both the locking grooves 37a and 37b. A continuous portion between the side surface and the inner peripheral surface of the outer ring 5d or the outer peripheral surface of the inner ring 6c is a smooth surface that hardly damages the rolling surfaces of the balls 7 and 7 when the tandem angular ball bearing is assembled. Specifically, a convex curve having a radius of curvature of a cross-sectional shape of 0.2 mm or more is obtained by polishing each continuous portion. Moreover, even if such a continuous part is polished, it can be carried out simultaneously with other parts by using a rotary grindstone of a total type. Functions and effects other than the provision of the both locking grooves 37a and 37b and the side edges of each opening being smooth surfaces are the same as the first example of the reference example shown in FIGS. Since this is the same as the second example of the embodiment shown in FIG. It should be noted that making both side edges of the opening portions of both the locking grooves 37a and 37b smooth is carried out only in the aspect according to another invention (for example, the locking grooves are formed in the structure shown in FIGS. 1 to 5 described above). Can also be provided).

  The present invention is not limited to an apparatus incorporated in an automobile drive system such as an automotive differential gear or a transfer apparatus, but is incorporated in various rotating machine apparatuses, and a rotating shaft that rotates with a radial load and a thrust load applied thereto. Applicable to tandem angular ball bearings for bearings. In addition, the assembly order is not limited to the example shown unless otherwise specified, and each ball and cage are assembled on the outer diameter side of the inner ring as described in Patent Document 3 described above. In this state, the inner ring can be externally fitted and fixed to a rotary shaft such as a pinion shaft, and then the outer ring fitted and fixed to the housing or the like can be assembled around each ball. Furthermore, after the race rings such as the outer ring and the inner ring are fitted and fixed to the mating member, the balls can be assembled together with the cage on the inner diameter side or the outer diameter side of the race ring.

DESCRIPTION OF SYMBOLS 1, 1a Ball bearing 2 Ball bearing 3, 3a Pinion shaft 4 Pinion gear 5, 5a-5e Outer ring 6, 6a-6c Inner ring 7 Ball 8, 8a-8c Large diameter side cage 9, 9a, 9c Small diameter side cage 10 Large Diameter outer ring raceway 11 Small diameter outer ring raceway 12 Large diameter inner ring raceway 13 Small diameter inner ring raceway 14, 14 a Pocket 15, 15 a Pocket 16 a, 16 b Groove shoulder 17 a, 17 b Groove shoulder 18 a, 18 b Groove shoulder 19 a, 19 b Groove Shoulder portion 21, 21a Support portion 22, 22a Support hole 23 End surface 24 End surface 25a-25j Corner portion 26a-26d Inclined surface portion 27a, 27b Cylindrical surface portion 31 Inner ring side assembly 32 Engagement allowance 33, 33a, 33b Outer ring side assembly 34 鍔Part 35 Inward engagement part 36 Outward engagement part 37a, 37b Locking groove

Claims (4)

An outer ring having a large-diameter outer ring raceway having a relatively large diameter on one axial side of the inner peripheral surface and a small-diameter side outer ring raceway having a relatively small diameter on the other axial side;
An inner ring having a large-diameter inner ring raceway having a relatively large diameter on one axial side of the outer peripheral surface and a small-diameter side inner ring raceway having a relatively small diameter on the other axial side,
An annular large-diameter side cage having pockets at a plurality of locations in the circumferential direction and having a relatively large diameter;
An annular small-diameter side cage having pockets at a plurality of locations in the circumferential direction and having a relatively small diameter,
In a state of being held in each pocket of the large-diameter side cage, a large-diameter side ball train is provided that is freely rollable between the large-diameter side outer ring raceway and the large-diameter side inner ring raceway. Multiple balls,
A plurality of balls constituting a small-diameter-side ball array that is rotatably provided between the small-diameter side outer ring raceway and the small-diameter side inner ring raceway while being held in each pocket of the small-diameter side cage. And
In the tandem angular contact ball bearing in which each ball constituting the large diameter side ball row and each ball constituting the small diameter side ball row are given contact angles in the same direction,
The outer ring includes groove shoulders on both sides in the axial direction of the large-diameter side outer ring raceway and on the other side in the axial direction of the small-diameter side outer ring raceway ,
The inner ring includes a groove shoulder on each of one axial portion of the large-diameter side inner ring raceway and one axial portion of the small-diameter side inner ring raceway, and another axially other side portion of the large-diameter side inner ring raceway. And the axially other side portion of the small-diameter side inner ring raceway is not provided with a groove shoulder respectively,
The large-diameter side cage and the small-diameter side cage are provided with an engagement margin all around the inner periphery of the opening on the inner diameter side of each pocket. With each ball slightly smaller than the diameter and holding each ball in each of these pockets, these balls are prevented from coming out from the inside of each pocket to the inner diameter side.
Without elastically deforming the large-diameter side cage, each of the balls held in the pockets of the large-diameter side cage is closest to the inner diameter side of the large-diameter side cage. The diameter of the circumscribed circle of the ball is larger than the inner diameter of the groove shoulder portion existing on both axial sides of the large-diameter outer ring raceway.
A tandem angular contact ball bearing characterized by The outer ring, the axial both sides of the small-diameter side outer ring raceway, each include a groove shoulder portion, tandem angular contact type ball bearing according to claim 1. The outer ring is not provided with a groove shoulder on one axial side portion of the small diameter side outer ring raceway , and the large diameter side retainer and the small diameter side retainer are the outer ring , the large diameter side retainer, and the small diameter In a state in which an outer ring side assembly is formed by combining the side cage and each of the balls in the same positional relationship as the completed state as a ball bearing, the ends close to each other have a shape facing each other in the axial direction. A tandem angular ball bearing according to claim 1 . In order to constitute the tandem angular ball bearing according to any one of claims 1 to 3, the outer ring, the large-diameter side cage, the small-diameter side cage, and the balls are combined. An outer ring side assembly for tandem angular ball bearings .

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