JP5815367B2 - Tandem type double row angular contact ball bearing - Google Patents

Description

  The present invention relates to a tandem type double row angular contact ball bearing.

  As the bearing, there is an angular ball bearing capable of applying a radial load and an axial load in one direction. The ball and the inner ring / outer ring have a contact angle. The larger the contact angle, the greater the load capacity of the axial load, and the smaller the contact angle, the more advantageous for high-speed rotation.

  By the way, in order to reduce rolling resistance, there is a double row angular contact ball bearing (tandem type) as an alternative to the tapered roller bearing (Patent Document 1). In addition, there is one in which this tandem type double row angular ball bearing is used for an automobile transfer (Patent Document 2). A transfer is a 4WD vehicle that transmits the power coming from the transmission to the front and rear wheels. Usually, a differential device (differential device) is also built in. I'm calling. A double row angular contact ball bearing is a structure in which a single row angular contact ball bearing is combined on the back and the inner ring and outer ring are integrated into one body, so that it can load an axial load in both directions, and has a load capacity for moment load. It is a certain bearing.

  As shown in FIG. 5, the tandem type double-row angular ball bearing includes an inner ring 2 having double-row raceway surfaces 1a and 1b and double-row raceway surfaces 3a and 3b corresponding to the raceway surfaces 1a and 1b of the inner ring 2. And an outer ring 4 and double-row ball groups 5 and 6 interposed between the raceways 1a, 1b, 3a and 3b of each row of the inner ring 2 and the outer ring 4. The double row ball groups 5 and 6 have different pitch circle diameters. The balls 7 and 8 of the ball groups 5 and 6 are held by cages 9 and 10 disposed between the inner ring 2 and the outer ring 4.

  As shown in FIG. 6, the differential device described in Patent Document 2 includes a differential case 101, a differential reduction mechanism (not shown) arranged in the differential case 101, and a ring gear (see FIG. And a pinion shaft 105 that supports the pinion gear 104. The pinion shaft 105 is rotatably supported in the differential case 101 via bearings 106 and 107.

  And tandem type double row angular contact ball bearings are used for the bearings 106 and 107, respectively. One bearing 106 disposed on the pinion gear 104 side has a large-diameter side end surface 2a of the inner ring 2 (an end surface protruding to the pinion gear 104 side from the outer ring 4) press-contacts the end surface 104a of the pinion gear 104, and The end surface 4 a on the side opposite to the pinion gear is in pressure contact with a step surface 108 formed on the inner surface of the case 101.

  The other bearing 107 has a large-diameter side end surface 2a of the inner ring 2 (an end surface protruding to the side opposite to the pinion gear from the outer ring 4) press-contacts the end edge 100a of the pinion flange 100, and an end surface 4a of the outer ring 4 on the pinion gear side. The step 51 is in pressure contact with the step surface 109 formed on the inner surface of the case 51. Further, the pinion shaft 105 has a large diameter on the pinion gear 104 side to form a stepped portion 105a, and a sleeve 110 is interposed between the stepped portion 105a and the inner ring 2 of the other bearing 107.

  In this case, a preload is applied to the bearings 106 and 107 via the pinion flange 100 by screwing a nut member (not shown) to the threaded portion 111 at the end of the pinion shaft 105. That is, by applying preload to the bearings 106 and 107, the rigidity of the bearing support structure is increased, the position of the pinion shaft 105 is stabilized, and the meshing with the ring gear is improved.

  Further, the inner ring 2, the outer ring 4, the balls 7, 8 and the like of the bearings 106 and 107 are made of bearing steel such as SUJ2.

  Further, in the pinion shaft support bearing device shown in Patent Document 3, the pinion front side bearing is a single row angular ball bearing, and the axial clearance thereof is substantially the same as the small diameter row axial clearance of the tandem angular ball bearing of the pinion rear side bearing. It is prescribed. Thereby, the ratio of the load distribution between the single row angular contact and the tandem angular contact ball bearing is made uniform.

Japanese Patent No. 181547 Special Table 2002-52370 JP 2004-190728 A

  By the way, when both the pinion front and rear bearings are tandem angular ball bearings, the clearance cannot be set by the conventional technology. For this reason, in the thing of the said patent document 3, the pinion front side bearing is made into the single row angular ball bearing, and the pinion rear side bearing is made into the tandem angular ball bearing.

  However, although the load on the pinion front side is smaller than that on the pinion rear side, both pinion front and rear bearings must be tandem angular ball bearings to prevent excessive surface pressure and shoulder climbing. There is. For this reason, conventionally, a differential using a tandem angular ball bearing is generally a tandem angular ball bearing for both the pinion front and rear bearings.

  In this way, when both the pinion front and rear bearings are tandem angular ball bearings, if the load distribution of the large diameter row and small diameter row in the tandem angular ball bearing alone is not even, either the large diameter row or the small diameter row On the other hand, there is a possibility that the load ratio increases and the service life is shortened.

  Therefore, in view of such circumstances, the present invention aims to provide a tandem double-row angular contact ball bearing in which the load ratio between the large-diameter row and the small-diameter row is equalized when a load is applied, and the life can be extended. To do.

The Dandem double row angular contact ball bearing of the present invention includes an inner ring having a double row raceway surface, an outer ring having a double row raceway surface corresponding to the raceway surface of the inner ring, and a raceway surface between each row of the inner ring and the outer ring. Tandem type double-row angular contact ball bearings having double-row ball groups interposed with different pitch circle diameters, which accommodate balls only on the small-diameter row side when no load is applied. a set width when, have inner and outer rings is larger than the set width when accommodating the balls of the ball group only large径列side, at the time of load application, the balls of the ball group only the small-diameter column-side The inner ring and the outer ring are the same when the group width when accommodated and the group width when the balls of the ball group are accommodated only on the large diameter row side. Here, the set width is the axial length of the entire ball bearing.

  According to the tandem double-row angular contact ball bearing of the present invention, it is possible to equalize the load ratio between the small diameter row side and the large diameter row side when a load is applied. The load with the same assembly width when the load is applied is a preload load, for example, an initial load applied to the pinion shaft support bearing of the differential device.

In addition, other Dandem double row angular contact ball bearings include an inner ring having a double row raceway surface, an outer ring having a double row raceway surface corresponding to the raceway surface of the inner ring, and a raceway surface of each row of the inner ring and the outer ring. A tandem double-row angular contact ball bearing with a double-row ball group interposed between them with different pitch circle diameters, and accommodates the balls of the ball-group only on the small-diameter row side when no load is applied The inner group and outer ring have a set width that is larger than the set width when the ball group balls are accommodated only on the large diameter row side, and the ball group balls only on the small diameter row side when a load is applied. The inner ring and the outer ring have the same amount of elastic displacement in the axial direction when the ball is accommodated and the amount of elastic displacement in the axial direction when the balls of the ball group are accommodated only on the large diameter row side . By setting in this way, the set width when the balls are accommodated only on the small diameter row side and the set width when the balls are accommodated only on the large diameter row side can be stably made the same. At this time, at least the axial elastic displacement amount when the ball group ball is accommodated only on the small diameter row side and the axial elastic displacement amount when the ball group ball is accommodated only on the large diameter row side are at least the ball diameter, the initial contact angle, the curvature of the inner ring raceway surface, and on the basis of parameters including the curvature of the raceway surface of the outer ring can be Rukoto the same.

  The cage material may be made of at least one selected from, for example, polyamide, polyphenylene sulfite, and polyether ether ketone. That is, the cage can be a resin cage such as engineering plastic.

  The cage is preferably filled with a reinforcing material, and the filling rate is preferably 30% or more. The reinforcing material may be a fiber reinforced plastic (FRP) such as carbon fiber or glass fiber.

  The ball may be made of ceramics. Thus, by making the ball made of ceramics, the contact portion between the ball and the outer ring raceway surface and the inner ring raceway surface as compared with the ball bearing using a steel ball that has been generally used conventionally. It is possible to reduce the rolling friction acting on the. In other words, since ceramic balls and outer rings and inner rings made of hard metal such as steel are brought into contact with each other, different materials are in contact with each other. Is reduced. At the same time, ceramic balls have a smaller amount of elastic deformation than steel balls, so that the Hertzian contact ellipse present at the abutting portion is reduced. Furthermore, since the specific gravity is smaller than that of metal and the inertial mass is small, the rolling resistance of the ceramic ball itself is also small.

  At least one member of the inner ring, the outer ring, and the ball may be subjected to nitriding treatment. Here, the nitriding treatment is performed by exposing a steel containing a nitride-forming element such as aluminum, chromium or molybdenum to an atmosphere containing ammonia or nitrogen and heating it in a temperature range below the austenitizing temperature. This is a treatment in which nitrogen is infiltrated into the vicinity of the surface (within 1 mm) and cured. Abrasion resistance, fatigue resistance, corrosion resistance, and heat resistance can be improved.

  At least any one member of the inner ring, the outer ring, and the ball may be strengthened by crystal grain refinement. The crystal grain refinement strengthening process is, for example, a process of second quenching the carbonitrided structure at a low temperature. By applying this grain refinement strengthening, the crystal grains of the steel material become smaller and the fatigue strength is improved.

  Carburized steel may be sufficient as at least any one member among an inner ring | wheel, an outer ring | wheel, and a ball | bowl. Here, the carburized steel is steel whose surface has been hardened by carburizing (chadding) after carburizing. Carburization is a process of heating in a medium containing carbon in order to increase the carbon content of the steel surface. Solid carburization with coke, charcoal, etc., liquid carburization with cyanide, gas carburization with carbon monoxide, methane, etc. Carburized steel has high wear resistance and is persistent inside.

  The carburized steel may be chromium molybdenum steel or chrome steel. Examples of chromium molybdenum steel include SMn420 and SCM435. Examples of chromium steel include SCr415 and SCr420.

  The tandem double-row angular contact ball bearing includes a differential case, a differential reduction mechanism disposed in the differential case, a pinion gear that meshes with a ring gear of the differential reduction mechanism, and a pinion shaft that supports the pinion gear. It can be used for a differential device.

  In the tandem double-row angular contact ball bearing of the present invention, when the load is applied, the load ratio of the small diameter row side and the large diameter row side can be made uniform, and the life can be extended.

  In particular, by setting the axial elastic displacement amount when the ball is accommodated only on the small diameter row side and the axial elastic displacement amount when the ball is accommodated only on the large diameter row side to be the same, the load The load ratio can be made more uniform.

  If resin cages such as engineering plastics such as polyamide, polyphenylene sulfite, and polyether ether ketone are used, the weight is small and the coefficient of friction is small, which is suitable for reducing torque loss and cage wear at the time of starting the bearing. In particular, since the resin cage can be formed by injection molding, there is an advantage that even a cage having a unique shape can be easily manufactured.

  When the reinforcing material is filled at a filling rate of 30% or more, the strength of the cage can be improved, and the tandem double-row angular ball bearing is stable.

  If ceramic balls are used, the weight can be reduced, the contact area can be reduced, and the torque of the bearing can be reduced.

  For at least one of the inner ring, outer ring, and ball, nitriding treatment, crystal grain refinement strengthening, or carburizing steel use, take advantage of the characteristics of each steel material Thus, the service life can be further extended.

  By using the tandem type double-row angular ball bearing as described above for the differential device, a high-quality differential device can be provided.

It is a principal part expanded sectional view of the tandem type double row angular contact ball bearing which shows the embodiment of the present invention. In the tandem double-row angular contact ball bearing shown in FIG. 1, the assembled width in a state where the balls are accommodated only on the small diameter side is shown, (a) is an enlarged cross-sectional view of the main part when no load is applied, (b) It is a principal part expanded sectional view at the time of load loading. In the tandem double-row angular contact ball bearing shown in FIG. 1, the assembled width in a state in which balls are accommodated only on the large diameter side is shown, (a) is an enlarged cross-sectional view of the main part when no load is applied, (b) These are the principal part expanded sectional views at the time of load loading. It is sectional drawing of the differential apparatus using the tandem type | mold double row angular contact ball bearing shown in the said FIG. It is sectional drawing of the conventional tandem type double row angular contact ball bearing. It is sectional drawing of the differential apparatus using the conventional tandem type double row angular contact ball bearing.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows a tandem double-row angular contact ball bearing according to the present invention. The tandem double-row angular contact ball bearing includes an inner ring 12 having double-row raceway surfaces 11a and 11b, and a raceway surface 11a of the inner ring 12; The outer ring 14 having double-row raceway surfaces 13a and 13b corresponding to 11b, and the double-row ball groups 15 and 16 interposed between the raceways 11a, 11b, 13a and 13b of each row of the inner ring 12 and the outer ring 14 With. The ball groups 15 and 16 have different pitch circle diameters D1 and D2, respectively. In this case, D1 <D2. On the outer diameter surface of the inner ring 12, a circumferential groove 23 is formed between the raceway surfaces 11a and 11b.

The ball groups 15 and 16 are held by holders 19 and 20, respectively. One retainer 19 includes a ring-shaped main body portion 19a in which a plurality of pockets 30 are formed at a predetermined pitch along the circumferential direction, and an outer surface projecting in an outer diameter direction at an axially inner end portion of the main body portion 19a. A flange portion 19b and an inner flange portion 19c protruding in the inner diameter direction are provided at the axially inner end portion of the main body portion 19a. The other cage 20 is made of a ring body in which a plurality of pockets 31 are formed at a predetermined pitch along the circumferential direction.
Then, in the pockets 30 and 31 of the cages 19 and 20, balls 27 and 28 as rolling elements are held.

  Further, the contact angle α1 of the small-diameter side ball 27 is made larger than the contact angle α2 of the large-diameter side ball 28. A contact point Pa (Pb) of the ball 27 (28) with the raceway surface 11a (11b) of the inner ring 12 and a contact point Qa (Qb) of the ball 27 (28) with the raceway surface 13a (13b) of the outer ring 14 are defined. A straight line ma (mb) is formed, and a straight line n orthogonal to the central axis L of the bearing is formed. An angle α1 (α2) formed by the straight line ma (mb) and the straight line n is a contact angle. In the present invention, α1> α2. If the contact angle is large, the load capacity of the axial load is increased. Conversely, if the contact angle is small, it is advantageous for high-speed rotation. Therefore, in the present invention, in order to take advantage of both the advantage of a large contact angle and the advantage of a small contact angle, the contact angle of the small-diameter side ball is made larger than the contact angle of the large-diameter side ball.

  The cages 19 and 20 are resin cages. This resin is preferably an engineering plastic. Here, the engineering plastic is an abbreviation for engineering plastics, which is excellent in heat resistance among synthetic resins and can be used in fields where strength is required. Engineering plastics include general-purpose engineering plastics and super engineering plastics. The engineering plastics used for the cages 19 and 20 include both. The following are typical examples. These are examples of engineering plastics, and engineering plastics are not limited to the following. The resin holders 19 and 20 can be formed by, for example, injection molding.

  General-purpose engineering plastics include polycarbonate (PC), polyamide 6 (PA6), polyamide 66 (PA66), polyacetal (POM), modified polyphenylene ether (m-PPE), polybutylene terephthalate (PBT), GF reinforced polyethylene terephthalate (GF). -PET), ultra high molecular weight polyethylene (UHMW-PE) and the like. Super engineering plastics include polysulfone (PSF), polyethersulfone (PES), polyphenylene sulfide (PPS), polyarylate (PAR), polyamideimide (PAI), polyetherimide (PEI), and polyetheretherketone. (PEEK), liquid crystal polymer (LCP), thermoplastic polyimide (TPI), polybenzimidazole (PBI), polymethylbenten (TPX), poly 1,4-cyclohexanedimethylene terephthalate (PCT), polyamide 46 (PA46), There are polyamide 6T (PA6T), polyamide 9T (PA9T), polyamide 11,12 (PA11,12), fluororesin, polyphthalamide (PPA) and the like.

  When the cages 19 and 20 are such resin cages, it is preferable to fill a reinforcing material (resin reinforcing material). The filling rate is preferably 30% or more. The reinforcing material may be a fiber reinforced plastic (FRP) such as carbon fiber or glass fiber. Here, the carbon fiber is a fiber made by carbonizing an acrylic fiber or pitch (by-products such as petroleum, coal, coal tar, etc.) at a high temperature. Carbon fibers using the former raw material are classified as PAN (Polyacrylonitrile), and carbon fibers using the latter are classified as PITCH. It is an aggregate of carbon in a broad sense. High strength is obtained by the combination of graphite. Graphite is an elemental mineral consisting of carbon. Carbon fiber is excellent in wear resistance, heat resistance, thermal stretchability, acid resistance, electrical conductivity, tensile resistance, and the like, and has an advantage of being lighter than metals such as aluminum. Further, the glass fiber is a fibrous material made by thinly stretching a molten glass and rapidly solidifying it. They are classified into long fibers and short fibers according to the fiber type, and are roughly classified into alkali glass fibers and alkali-containing glass fibers according to the composition. Glass fiber is excellent in corrosion resistance, heat resistance, moisture resistance, and electrical insulation. For this reason, it becomes a lightweight and strong raw material by mixing carbon fiber and glass fiber with resin.

  By the way, in this bearing, any member of the inner ring 12, the outer ring 14, and the balls 27 and 28 is made of carburized steel such as SCM420 (chromium molybdenum steel), SCM435 (chromium molybdenum steel), SCr415 (chromium steel). Is. Here, the carburized steel is steel whose surface has been hardened by carburizing (chadding) after carburizing. Carburization is a process of heating in a medium containing carbon in order to increase the carbon content of the steel surface.

  For carburizing, for example, the following heat treatment process is performed. First, preheating at a predetermined temperature (for example, 840 ° C.) is performed for a predetermined time (for example, 30 minutes), and then carburizing process (for example, about 90 to 150 minutes) by heating to a predetermined high temperature (for example, 930 ° C.). I do. Next, for example, diffusion is performed for about 30 minutes, and for example, quenching at about 850 ° C. is performed for about 30 minutes.

  Further, any member of the inner ring 12, the outer ring 14, and the balls 27 and 28 may be subjected to nitriding treatment. Here, the nitriding treatment is performed by exposing a steel containing a nitride-forming element such as aluminum, chromium or molybdenum to an atmosphere containing ammonia or nitrogen and heating it in a temperature range below the austenitizing temperature. This is a treatment in which nitrogen is infiltrated into the vicinity of the surface (within 1 mm) and cured. Abrasion resistance, fatigue resistance, corrosion resistance, and heat resistance can be improved.

  Further, at least any one member of the inner ring 12, the outer ring 14, and the balls 27 and 28 may be strengthened by crystal grain refinement. The crystal grain refinement strengthening process (FA process) is, for example, a process of second quenching the carbonitrided structure at a low temperature. By applying this grain refinement strengthening, the crystal grains of the steel material become smaller and the fatigue strength is improved.

  In the FA treatment, nitriding treatment is performed for the purpose of lowering the Ac1 transformation point of steel while sufficiently dissolving carbon in martensite at the time of primary quenching, and then the holding temperature of the secondary quenching process is lowered. This is a method for obtaining fine crystal grains.

  For the inner ring 12 and the outer ring 14, bearing steel such as SUJ2 can be used. The balls 27 and 28 can be made of steel balls (SUJ2), stainless steel balls (SUS440C), carbon steel balls (SWCH10), ceramic balls, and the like.

When ceramic balls are used for the balls 27 and 28, a combination of different materials is used for the bearing steel inner ring 12 and outer ring 14, and the specific gravity is smaller than that of the steel rolling elements. And wear is reduced. The type of ceramic constituting the balls 27 and 28 is not particularly limited. For example, silicon nitride (Si ₃ N ₄ ), zirconia (ZrO ₂ ), silicon carbide (SiC), alumina (Al ₂ O ₃ ) and the like are preferable. Can be used for In consideration of friction characteristics, workability, specific gravity, etc., silicon nitride is particularly desirable. Further, the forming method of the ceramic rolling element is not particularly limited, and any forming method such as normal pressure, pressurization, and HIP can be used. These ceramic rolling elements are primary molded by die molding or granulation molding, and the ball obtained by secondary molding by atmospheric pressure sintering, pressure sintering, HIP sintering, etc. is finished by lapping etc. To be a completed ball. Of these, the cheapest raw spheres can be obtained by granulation molding-atmospheric pressure sintering, but if higher performance is required, those subjected to HIP sintering or pressure sintering are desirable.

  FIG. 4 shows a differential apparatus using a tandem type double-row angular ball bearing according to the present invention. This differential apparatus includes a differential case 51, a differential reduction mechanism 52 arranged in the differential case 51, a differential A pinion gear 54 that meshes with the ring gear 53 of the speed reduction mechanism 52 and a pinion shaft 55 that supports the pinion gear 54 are provided, and the pinion shaft 55 is rotatably supported in the differential case 51 via bearings 56 and 57.

  The tandem double-row angular ball bearings shown in FIGS. 1 and 2 are used for the bearings 56 and 57, respectively. One of the bearings 56 disposed on the pinion gear 54 side is in contact with the end portion 33 of the inner ring 12 of the bearing 56, that is, the end surface 12a, on the end surface 54a of the pinion gear 54 of the pinion shaft 55, and the end surface of the outer ring 14 on the side opposite to the pinion gear. 14 a is in pressure contact with a step surface 58 formed on the inner surface of the case 51.

  In the other bearing 57, the end portion 33 of the inner ring 12, that is, the end surface 12 a (the end surface on the opposite flange side) is pressed against the end edge 50 a of the pinion flange 50, and the end surface 14 a of the outer ring 14 on the pinion gear side is on the inner surface of the case 51. It is in pressure contact with the formed step surface 59. A sleeve 60 is interposed between the one bearing 56 and the inner ring 12 of the other bearing 57.

  In this case, a preload is applied to the bearings 56 and 57 via the pinion flange 50 by screwing the nut member 62 into the threaded portion 61 at the end of the pinion shaft 55.

  By the way, in the tandem double-row angular contact ball bearing of the present invention, when no load is applied, the assembled width A0 (see FIG. 2A) when the balls 27 are accommodated only on the small-diameter row side is set on the large-diameter row side. Only the set width B0 (see FIG. 3A) when the ball 28 is accommodated is set. That is, A0> B0. Here, the set width is the axial length of the entire ball bearing.

  When the load is applied, the assembled width A1 (see FIG. 2B) when the balls 27 are accommodated only on the small diameter row side and the assembled width B1 when the balls 28 are accommodated only on the large diameter row side (see FIG. 2). 3 (b)) is set the same. The load with the same assembly width when the load is applied is a preload load, for example, an initial load applied to the pinion shaft support bearing of the differential device.

  In addition, when the preload is applied, the axial elastic deformation amount δa1 when the ball 27 is accommodated on the small diameter side (small diameter row) (the state shown in FIG. 2B) and the ball on the large diameter side (large diameter row). When 28 is accommodated (state shown in FIG. 3B), the axial elastic deformation amount δa2 is set to be the same. In this case, it is set based on parameters such as the ball diameter of the ball 27 (28), the initial contact angle, the curvature of the raceway surface 11a (11b) of the inner ring 12, the curvature of the raceway surface 13a (13b) of the outer ring 14.

Here, the axial elastic deformation amount δa1 (δa2) is expressed by the following equation (1). In Equations 1 and 2, Da1 (Da2) is the ball diameter (steel ball diameter), α1 (α2) is the initial contact angle (contact angle when no load is applied), and C1 is the raceway surface of the inner ring 12. 11 a and an elastic constant determined by the curvature of the raceway surface 13 a of the outer ring 14. C2 is an elastic constant determined by the curvature of the raceway surface 11b of the inner ring 12 and the raceway surface 13b of the outer ring 14.

Further, P ₀ in Equation 1 (Equation 2) is a load applied to one ball, and is represented by the following Equation 3 (Equation 4). Here, Z is the number of balls, and Fa is a preload (axial load).

  In the tandem double-row angular contact ball bearing of the present invention, when the load is applied, the load ratio of the small diameter row side and the large diameter row side can be made uniform, and the life can be extended.

  In particular, the axial elastic displacement when the ball 27 is accommodated only on the small diameter row side and the axial elastic displacement when the ball 28 is accommodated only on the large diameter row side are set to be the same. Further, the load load ratio can be made more uniform.

  If resin cages such as engineering plastics such as polyamide, polyphenylene sulfite, and polyether ether ketone are used, the weight is small and the coefficient of friction is small, which is suitable for reducing torque loss and cage wear at the time of starting the bearing. In particular, since the resin cage can be formed by injection molding, there is an advantage that even a cage having a unique shape can be easily manufactured.

  When the reinforcing material is filled at a filling rate of 30% or more, the strength of the cage can be improved, and the tandem double-row angular ball bearing is stable.

  If the ceramic balls 27 and 28 are used, the weight can be reduced, the contact area can be reduced, and the torque of the bearing can be reduced.

  In the case where at least one member of the inner ring 12, the outer ring 14, and the balls 27, 28 is subjected to nitriding treatment, crystal grain refinement strengthening, or carburizing steel, each steel material This makes it possible to take advantage of the characteristics of the material and to further extend the service life.

  By using the tandem type double-row angular ball bearing as described above for the differential device, a high-quality differential device can be provided.

  As described above, the embodiments of the present invention have been described. However, the present invention is not limited to the above-described embodiments, and various modifications can be made. For example, the tandem double-row angular ball bearing has various configurations other than the differential device. It can be used for machines, devices, tools, etc. Further, the number of balls 27 and 28 of the ball groups 15 and 16, the diameter of the sphere, and the like can be arbitrarily changed. Furthermore, in the said embodiment, although the ball groups 15 and 16 were 2 rows, 3 or more rows may be sufficient. The difference between the pitch circle diameters D1 and D2 of the ball groups 15 and 16 can be variously changed according to the machine, device, tool and the like to be used. The carburized steel used is not limited to SCM420 (chromium molybdenum steel), SCM435 (chromium molybdenum steel), and SCr415 (chromium steel), and may be other carburized steel.

  The cages 19 and 20 may be iron plate cages (formed by punching a metal plate). As the metal plate, rolled steel plate such as cold rolled steel plate (SPC) and hot rolled mild steel plate (SPH), spring steel, and the like can be used. In the case of a cold rolled steel plate (SPC) or a hot rolled mild steel plate (SPH), it is preferable to subject the surface to surface hardening treatment such as carbonitriding treatment or gas soft nitriding treatment. By making the cages 19 and 20 made of iron plate, the rigidity of the cage can be increased, and the balls 27 and 28 can be stably held over a long period of time. Moreover, it is excellent in oil resistance and can prevent material deterioration due to immersion in oil.

11a, 13a Raceway surface 12 Inner ring 14 Outer ring 15, 16 Ball group 19, 20 Cage 27, 28 Ball 51 Differential case 52 Differential reduction mechanism 54 Pinion gear 55 Pinion shaft

Claims (10)

An inner ring having a double-row raceway surface, an outer ring having a double-row raceway surface corresponding to the raceway surface of the inner ring, and a raceway surface in each row of the inner ring and the outer ring are interposed with different pitch circle diameters. A tandem type double row angular contact ball bearing with a double row ball group,
When no load is applied, there are inner and outer rings whose combined width when the ball group ball is accommodated only on the small diameter row side is larger than that when the ball group ball is accommodated only on the large diameter row side. and, at the time of load application, the inner and outer rings and a set width when accommodating the balls of the ball group only to the set width and large径列side when accommodating a ball of the ball group only the small-diameter column-side in the same tandem double row angular contact ball bearing, characterized in that a. An inner ring having a double-row raceway surface, an outer ring having a double-row raceway surface corresponding to the raceway surface of the inner ring, and a raceway surface in each row of the inner ring and the outer ring are interposed with different pitch circle diameters. A tandem type double row angular contact ball bearing with a double row ball group,
When no load is applied, there are inner and outer rings whose combined width when the ball group ball is accommodated only on the small diameter row side is larger than that when the ball group ball is accommodated only on the large diameter row side. When the load is applied, the axial elastic displacement amount when the ball group ball is accommodated only on the small diameter row side, and the axial elastic displacement amount when the ball group ball is accommodated only on the large diameter row side features and to filter tandem type double row angular contact ball bearings to be the inner ring and the outer ring was the same. An axial elastic displacement amount when the ball group ball is accommodated only on the small diameter row side and an axial elastic displacement amount when the ball group ball is accommodated only on the large diameter row side are at least the ball diameter, initial value contact angle, the curvature of the inner ring raceway surface, and on the basis of parameters including the curvature of the raceway surface of the outer ring, a tandem-type double row angular contact ball bearing according to claim 2, characterized in that it has the same.   The tandem type double row angular structure according to any one of claims 1 to 3, wherein the cage material is made of at least one selected from polyamide, polyphenylene sulfite, and polyether ether ketone. Ball bearing.   The tandem double-row angular ball bearing according to any one of claims 1 to 4, wherein the cage is filled with a reinforcing material, and a filling rate thereof is set to 30% or more.   The tandem double-row angular contact ball bearing according to any one of claims 1 to 5, wherein the ball is made of ceramics.   6. The tandem double-row angular contact ball bearing according to claim 1, wherein at least any one member of an inner ring, an outer ring, and a ball is subjected to nitriding treatment.   6. The tandem double-row angular contact ball bearing according to claim 1, wherein at least any one member of an inner ring, an outer ring, and a ball is subjected to grain refinement strengthening. .   6. The tandem double-row angular contact ball bearing according to claim 1, wherein at least one member of the inner ring, the outer ring, and the ball is carburized steel.   The tandem-type double-row angular contact ball bearing according to any one of claims 1 to 9, wherein a differential case, a differential reduction mechanism disposed in the differential case, and a differential reduction mechanism are provided. A tandem double-row angular contact ball bearing characterized by being used in a differential device including a pinion gear meshing with a ring gear and a pinion shaft that supports the pinion gear.

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