Double-row tapered roller bearing with low energy consumption and long service life

Abstract

The invention provides a double-row tapered roller bearing with low energy consumption and long service life. The bearing comprises an inner ring, an outer ring, a roller, a retainer, an outer flange and an oil seal. Compared with an existing bearing, the bearing has the advantages of being good in assembling performance, compact in structure, large in load, low in noise, low in driving torque, ultralow in temperature rise, ultralow in friction torque, ultralow in cost, integrated, super-energy-saving, super-long in mileage, free of maintenance, super-long in service life, high in strength, rigidity, reliability and stability and the like, the efficiency of a transmission system is remarkably improved, and the service life of the transmission system is prolonged. The energy consumption is obviously reduced; the energy is saved; the environment is protected.

Description

Technical Field

[0001] The invention relates to the field of rolling bearings, and in particular to a low-energy-consumption and long-life double-row tapered roller bearing. Background Art

[0002] As the core supporting element of the mechanical transmission system, bearings are known as the "joints" of industry. Their performance directly affects the reliability, energy efficiency and life of mechanical equipment. As modern industry develops towards high speed, heavy load and long life, bearings need to meet the stringent requirements of load capacity and dynamic performance. However, existing bearings have the following problems that need to be solved:

[0003] A. Clearance design paradox caused by temperature rise:

[0004] The clearance of the bearing has a significant impact on the bearing load, life, temperature rise, noise, vibration, etc. Figure 5 This is a diagram of the relationship between the axial clearance of the bearing and the relative bearing life. Zero clearance is the best working state of the rolling bearing. As the clearance increases, the noise, vibration, temperature rise and load of the rolling bearing become worse. Due to the existence of bearing clearance, the internal parts of the bearing cannot bear the load evenly and uniformly. For example, the raceway of the stationary inner ring or outer ring is divided into a load area and a non-load area. The entire raceway working surface is only borne by the local load area. The peeling of the working surface occurs in this area. This is caused by the stress concentration problem. Due to the existence of clearance, the inner and outer raceways and rollers actually bear super loads instead of uniform and average loads, which greatly shortens the bearing life. For existing rail transit wheels (or axle boxes) bearings, whether it is a double-row tapered roller bearing or a double-row cylindrical roller bearing, since the temperature of the inner ring is higher than that of the outer ring, a certain amount of clearance must be left to ensure that the bearing does not get stuck or stuck. The existing structure makes it impossible to adjust the bearing clearance to the optimal state, resulting in performance degradation, shortened life, and the need for regular overhaul and maintenance.

[0005] Figure 4 This is a schematic diagram of the heating parts of the existing double-row tapered roller bearings for automobile wheels. Figure 6 This is a schematic diagram of the heating parts of the double-row tapered roller bearings of existing rail transit vehicle wheelsets (or axle boxes). Figure 7 This is a schematic diagram of the heating parts of the double-row cylindrical roller bearings of existing rail transit vehicle wheelsets (or axle boxes). Figure 4 and Figure 6They are all double-row tapered roller bearings, but with different contact angles. When the weight and wind resistance of the motor vehicle are applied to the bearing in the form of radial force, heat is generated between the roller and the inner and outer raceways and the large rib due to friction. The heat generated by the rolling friction between the roller and the inner and outer raceways is almost the same, but because there is sliding friction between the large end face of the roller and the large rib, the sliding friction coefficient between the two friction surfaces is much larger than the rolling friction coefficient. Therefore, the roller and the inner ring generate the most heat, the roller and the inner ring have the largest temperature rise, and the thermal expansion of the roller and the inner ring is also greater than that of the outer ring. In order to ensure that the bearing does not "get stuck" or even "get stuck", a certain amount of clearance must be considered in the design of the bearing; for the existing rail transit wheels (or axle boxes) Figure 7 As for the double-row cylindrical roller bearing shown in the figure, since rail transit vehicles run in a straight line in most sections, the wheelset (or axle box) bearings only bear radial loads, and only rolling friction is generated between the rollers and the inner and outer raceways. The heat generated by the rolling friction between the rollers and the inner and outer raceways is almost the same, but because the inner hole of the inner ring is connected to the shaft, when the heat is transferred from the inner ring to the shaft, the heat can only be dissipated from the end face of the shaft, and the outer circle of the outer ring is connected to the housing hole, the heat can be easily dissipated through the housing, and the outer circle area of ​​most bearings is about twice that of the inner circle of the inner ring. In this way, the heat dissipation effect of the outer ring is much higher than that of the inner ring, resulting in a higher temperature of the inner ring than the outer ring. In order to prevent the bearing temperature from rising to a certain level and causing "stuck" or even "stuck" accidents, clearance must be left for the bearing in the design stage.

[0006] B. Thermal management and energy consumption issues:

[0007] The temperature rise of bearings is divided into normal temperature rise and abnormal temperature rise. Normal temperature rise refers to the temperature rise that matches the working conditions of the bearings. For example, the motor bearings only bear pure radial loads, and their temperature rise is normal temperature rise. Abnormal temperature rise refers to the temperature rise caused by the mismatch between the bearings and the working conditions they bear, such as the temperature rise caused by the clearance of the bearings, and the existing motor vehicle hub bearings are designed with an angular contact structure inside to bear a certain axial force. Under normal working conditions, the wheel hub bearings of motor vehicles only bear pure radial loads and only bear axial loads when turning. However, due to the angular contact structure inside, even if the motor vehicle travels in a straight line for more than 99.99% of the time, derived axial loads are still generated inside. The friction torque generated by this derived axial load is 100% converted into heat, resulting in abnormal temperature rise of the bearing. If the abnormal temperature rise of the bearing reaches a certain level, it will cause the evaporation and oxidation of the grease. Over time, the grease will become dry, aged, and ineffective, causing the friction and wear inside the bearing to increase, and ultimately causing the bearing to burn out and become scrapped. Almost all motor vehicles will generate derived axial loads when traveling in a straight line. The derived axial loads will inevitably produce friction torques. If the motor vehicle is to travel normally, this derived friction torque must be overcome, which consumes energy. The additional increase in energy consumption also increases the operating costs of the motor vehicle.

[0008] C. Lubrication and sealing system defects:

[0009] Whether it is the first to third generation wheel hub units for passenger cars or the first and second generation wheel hub units for commercial vehicles, they are all double-row angular contact bearings, and the contact angles are mostly in the range of 13° to 36° ( Figure 4 and 16 ), the frictional heat causes the grease to deteriorate faster, and the grease cannot be replaced. The so-called lifetime maintenance-free hub unit is often actually because the aftermarket cannot remove the seal ring and replace the grease, resulting in a maintenance-free mileage far lower than the design value. When the grease of the rail transit wheel set or axle box bearing needs to be replaced, even if all the bearing parts are still intact, the seal cover and cage still need to be replaced, which increases the maintenance cost.

[0010] Therefore, it is of great significance to develop a double-row tapered roller bearing with low energy consumption and long life. Summary of the invention

[0011] The purpose of the present invention is to provide a method for solving the problems existing in the prior art.

[0012] The technical solution adopted to achieve the purpose of the present invention is as follows: a low-energy-consumption and long-life double-row tapered roller bearing is provided to solve the problems existing in the prior art.

[0013] The technical solution adopted to achieve the purpose of the present invention is as follows: a low-energy consumption and long-life double-row tapered roller bearing, the double-row tapered roller bearing comprising two inner rings, two sealing rings, two outer ribs, two retainers, an outer ring and two rows of tapered rollers.

[0014] An inner raceway is provided on the circumferential outer circle of the middle section of the two inner rings. The inner raceway is in the shape of a conical surface. The portion of the inner ring located at the small end of the inner raceway is marked as a small head, and the portion located at the large end of the inner raceway is marked as a large head. A cylindrical surface is provided on the outer wall of the small head, and a cylindrical surface is provided on the outer wall of the large head. The small heads of the two inner rings are in contact with each other.

[0015] The inner hole of the outer ring includes two outer raceways, and a cylindrical section is between the two outer raceways. The outer raceways are in the shape of a conical surface. The small diameter ends of the two outer raceways are connected to the cylindrical section.

[0016] The two outer ribs include an outer rib body and a step portion. The outer rib body is an annular structure as a whole. The outer rib body is arranged at both ends of the outer ring. The step portion is arranged on the inner end surface of the outer rib body. The step portion has a working surface that is close to the ball base surface of the tapered roller. The outer ring is sleeved on the outer side of the two inner rings. The outer raceway, the inner raceway and the step portion enclose a friction working portion.

[0017] The two retainers are arranged in the friction working part. The retainer has a tapered roller in the window. The tapered roller rolls in the friction working part. The retainer guides the tapered roller to rotate along the outer raceway, the inner raceway and the step portion. The tapered surface of the tapered roller contacts the inner raceway and the outer raceway, and the ball base surface contacts the step portion.

[0018] The two sealing rings seal the bearing from two sides of the bearing respectively.

[0019] Furthermore, the semi-cone angle of the outer raceway is 1° to 45°.

[0020] Furthermore, the outer ring and the outer rib are an integral structure or a split structure.

[0021] Furthermore, the cylindrical surface of the large end of the inner ring contacts the sealing lip of the sealing ring. The outer circle of the sealing ring contacts the outer circle surface or the inner circle surface of the outer rib body.

[0022] Furthermore, the sealing ring is fastened to the outer rib by screws.

[0023] The technical effects of the present invention are unquestionable:

[0024] A. It has the advantages of good assembly performance, compact structure, large load, low temperature rise, low noise, low friction torque, super energy saving, almost no clearance during normal operation, and super long life;

[0025] B. The heat generation is greatly reduced compared with the existing wheel hub bearings, and the evaporation, oxidation and aging speed of the grease are greatly reduced, and the bearing life is greatly extended accordingly;

[0026] C. For motor vehicles and rail transit wheels, this bearing is used. Since the ribs are moved from the inner ring to the outer ring, on the one hand, the smaller contact angle greatly reduces the heat generation. On the other hand, due to the sliding friction between the two ribs of the outer ring and the rollers, the heat generated by the outer ring and the roller is greater than that of the inner ring. However, since the heat dissipation condition of the outer ring is better than that of the inner ring, when the contact angle is properly selected, the inner and outer rings and the rollers can have the same temperature rise. When the original clearance value of this low-energy consumption and long-life double-row tapered roller bearing is properly designed, the clearance value after installation is between 0 and a small value. In this way, this low-energy consumption and long-life double-row tapered roller bearing is always in the best working state of nearly 0 clearance, and the maintenance-free mileage and life are greatly extended;

[0027] D. For rail transit wheels or axle box bearings, when this low-energy consumption and long-life double-row tapered roller bearing runs to a certain mileage and needs to replace the grease, due to the advanced structural design, if the seal cover and retainer are not damaged, there is no need to replace them, saving huge costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 This is a schematic diagram of a low-energy-consumption, long-life double-row tapered roller bearing product;

[0029] Figure 2 A schematic diagram of a low energy consumption and long life double row tapered roller bearing product with a different internal structure;

[0030] Figure 3 A schematic diagram of a low-energy-consumption, long-life rail transit double-row tapered roller bearing product with a different internal structure;

[0031] Figure 4 This is a schematic diagram of the internal heating of a double-row tapered roller bearing for an existing automobile wheel hub;

[0032] Figure 5 It is a schematic diagram of bearing axial clearance and relative bearing life;

[0033] A low energy consumption and long life double row tapered roller bearing-4-

[0034] Figure 6 This is a schematic diagram of the internal heating parts of the existing rail transit wheel set (axle box) double-row tapered roller bearing product;

[0035] Figure 7 This is a schematic diagram of the internal heating parts of the existing rail transit wheel set (axle box) double-row cylindrical roller bearing product;

[0036] Figure 8 This is a schematic diagram of the existing double-row tapered roller bearing products for rail transit wheelsets (axle boxes);

[0037] Fig. 9 This is a schematic diagram of the internal heating parts of a low-energy-consumption, long-life double-row tapered roller bearing product;

[0038] Fig.10 This is the force analysis diagram of the existing double-row tapered roller bearing;

[0039] Fig.11 This is a force analysis diagram of a low-energy-consumption, long-life double-row tapered roller bearing product;

[0040] Fig.12 This is a schematic diagram of the outer ring of a double-row tapered roller bearing with low energy consumption and long life;

[0041] Fig.13 A schematic diagram of a roller product of a low-energy-consumption, long-life double-row tapered roller bearing;

[0042] Fig.14 This is a schematic diagram of the inner ring of a double-row tapered roller bearing with low energy consumption and long life;

[0043] Fig.15 A schematic diagram of a retainer product for a low-energy-consumption, long-life double-row tapered roller bearing;

[0044] Fig.16 It is a schematic diagram of the internal forces of the first, second and third generation wheel hub units of existing passenger cars;

[0045] Fig.17 This is a schematic diagram of the second generation of low energy consumption and long life commercial vehicle double row tapered roller bearings;

[0046] Fig.18 A schematic diagram of an upgraded second-generation low-energy-consumption and long-life commercial vehicle double-row tapered roller bearing;

[0047] Fig.19 This is a schematic diagram of the third generation of low energy consumption and long life passenger car double row tapered roller bearings;

[0048] Fig. 20 A schematic diagram of a low energy consumption and long life double row tapered roller bearing product with a different internal structure;

[0049] Fig.21 This is a schematic diagram of the fourth generation of low energy consumption and long life passenger car double row tapered roller bearings;

[0050] Fig. 22 Schematic diagram of a fourth-generation low-energy, long-life passenger car double-row tapered roller bearing with a different internal structure.

[0051] Fig.23 The figure is a schematic diagram of a fuel vehicle drive axle main reducer assembly using double-row tapered roller bearings.

[0052] In the figure: inner ring 1, sealing ring 2, outer rib 3, retainer 4, outer ring 5, tapered roller 6, screw 7. DETAILED DESCRIPTION

[0053] The present invention is further described below in conjunction with the embodiments, but it should not be understood that the above subject matter of the present invention is limited to the following embodiments. Without departing from the above technical ideas of the present invention, various substitutions and changes are made according to the common technical knowledge and customary means in the art, which should all be included in the protection scope of the present invention.

[0054] As we all know, in theory, when the bearing clearance is 0, the rolling bearing is in the best working state. However, in actual work, due to the designers' lack of understanding of the actual operating conditions of the bearings, the designed bearings have the problem of large temperature rise, and the temperature rise of the various parts that make up the bearings is different. In most cases, the temperature rise of the inner ring and the rolling element is higher than that of the outer ring. Because the inner hole of the inner ring is connected to the shaft, when the heat is transferred from the inner ring to the shaft, the heat can only be dissipated from the outer end of the shaft, and the outer circle of the outer ring is connected to the housing hole, the heat can easily be dissipated through the housing, and the outer circle area of ​​most bearings is about 2 times that of the inner circle of the inner ring. In this way, the heat dissipation effect of the outer ring is much higher than that of the inner ring, resulting in a higher temperature of the inner ring than the outer ring. In order to prevent the bearing temperature from rising to a certain level and causing "stuck" or even "stuck" accidents, clearance must be left for the bearing, and the existence of clearance seriously affects the working state of the bearing, causing the rolling element and the raceways of the inner and outer rings to always be in a relatively uneven and non-uniform working state, resulting in a series of problems such as noise, vibration, temperature increase and shortened life. This seems to be a vicious circle, but designers can make innovative and optimized designs based on the actual operating conditions of the bearing during the design phase to minimize the temperature difference between the inner and outer rings of the bearing.

[0055] See also Figure 1 , Figure 2 and Figure 3 This embodiment provides a low-energy-consumption and long-life double-row tapered roller bearing, including an inner ring unit, two sealing rings 2, an outer rib 3, a retainer 4, an outer ring 5 and tapered rollers 6.

[0056] See also Fig.14 The inner ring 1. An inner raceway 101 is provided on the circumferential outer circle of the middle section of the inner ring 1. The inner raceway 101 is in the shape of a conical surface. The portion of the inner ring 1 located at the small end of the inner raceway 101 is marked as a small head, and the portion located at the large end of the inner raceway 101 is marked as a large head. A cylindrical surface 102 is provided on the outer wall of the small head, and a cylindrical surface 103 is provided on the outer wall of the large head. The small heads of the two inner rings 1 are in contact with each other.

[0057] See also Fig.12 The inner hole of the outer ring 5 includes two outer raceways 501 with a cylindrical section 502 in the middle. The outer raceways 501 are in a conical shape. The small diameter ends of the two outer raceways 501 are connected to the cylindrical section 502.

[0058] The outer rib 3 includes an outer rib body 301 and a step portion 302. The outer rib is a low energy consumption and long life double row tapered roller bearing -6-

[0059] The body 301 is an annular structure as a whole. The outer rib body 301 is arranged at both ends of the outer ring 5. The step portion 302 is arranged on the inner end surface of the outer rib body 301. The step portion 302 is a working surface that is close to the ball base surface 601 of the tapered roller 6. The outer ring 5 is sleeved on the outside of the two inner rings 1. The outer raceway 501, the inner raceway 101 and the step portion 302 enclose a friction working part.

[0060] See also Fig.13 and Fig.15 The two retainers 4 are arranged in the friction working part. The window of the retainer 4 contains a tapered roller 6. The tapered roller 6 rolls in the friction working part. The retainer 4 guides the tapered roller 7 to rotate along the outer raceway 501, the inner raceway 101 and the step 302 in the circumferential direction. The tapered surface of the tapered roller 6 contacts the inner raceway 101 and the outer raceway 501, and the ball base surface 601 contacts the step 302.

[0061] The two sealing rings 2 seal the bearing from two sides of the bearing respectively.

[0062] The technical effects of this embodiment have the advantages of good assembly performance, compact structure, large load, low maintenance cost, low temperature rise, low noise, low friction torque, super energy saving, almost no clearance during normal operation, and ultra-long life; and advantages in maintenance:

[0063] 1. The working principle of this low energy consumption and long life double row tapered roller bearing is always in 0 to small positive clearance:

[0064] This embodiment changes the internal structure of the bearing to achieve almost the same temperature rise of the inner and outer rings and the rollers. When the bearing is in a zero to slight positive clearance after loading, it can be ensured that the bearing is always in a nearly zero clearance working state during operation. The specific principle is as follows: Figure 6 and 9As shown in the figure, two large ribs are transplanted from the inner ring of the existing bearing to the two end faces of the outer ring. From the previous analysis, it can be seen that the two parts with the largest heat generation in the bearing have changed from the inner ring and the roller to the outer ring and the roller. The reduction in the heat generated by the inner ring reduces the heat transferred from the inner ring to the shaft that matches the inner hole, so the temperature rise of the inner ring is slowed down; although the outer ring and the roller generate the most heat due to friction, the surface area of ​​the outer circle of the outer ring is about twice that of the inner hole, and the speed at which the heat is dissipated into the air through the parts that match the outer circle of the bearing is much greater, so the temperature rise of the outer ring and the roller is also slowed down; by transplanting the two large ribs from the inner ring of the existing bearing to the two end faces of the outer ring, it can be seen that the two parts with the largest heat generation in the bearing have changed from the inner ring and the roller to the outer ring and the roller. By designing the contact angle a to an appropriate value, it can be ensured that the temperature rise of the inner and outer rings and the rollers is almost the same. Since the bearing is in a state of 0 to small positive clearance after installation, the bearing is always in a working state of 0 to small positive clearance. The working state of nearly 0 clearance also reduces the noise and vibration of the bearing itself to the lowest level, so that the rolling elements and the inner and outer raceways of the bearing are always in contact, and the number of rollers bearing the load is greatly increased, which completely eliminates the working condition where the rolling elements and the inner and outer raceways bear super loads locally due to clearance factors. In principle, the problem of premature peeling of the rolling elements and the inner and outer raceways is completely eliminated.

[0065] 2. The low-energy-consumption and long-life double-row tapered roller bearing of this embodiment can significantly reduce temperature rise and energy consumption:

[0066] By significantly reducing the contact angle a of the bearing (see Fig. 9 ), so that the derived axial force borne by each bearing part is reduced to the limit, resulting in a significant reduction in temperature rise and energy consumption, extending the speed at which the bearing grease or lubricating oil fails due to temperature rise, and also extending the life of the bearing itself.

[0067] It is worth noting that the low-energy consumption and long-life double-row tapered roller bearing of this embodiment is mainly to solve the problem that the double-row tapered roller bearings of existing motor vehicles need to have a certain amount of bearing clearance, that is, the clearance of the bearing needs to be controlled within a certain range during the production stage of the bearing. The current situation is that the wheel hub bearings of all motor vehicles such as cars, tractors, ordinary trains, subways and high-speed trains need to control the clearance, so the problem to be solved in this embodiment has a wide range of commonality, that is, through innovative design and production control, the working clearance of the bearing is always within the range of 0 to a very small positive clearance.

[0068] Embodiment 2:

[0069] The main contents of this embodiment are the same as those of Embodiment 1, wherein the semi-cone angle of the outer raceway 501 is selected to be 1° to 45°.

[0070] Embodiment 3:

[0071] The main contents of this embodiment are the same as those of Embodiment 1 or 2, wherein, see Figure 2 and Figure 3 The outer ring 5 and the outer rib 3 are an integrated structure or a split structure. Under the condition that the function remains unchanged, the split structure is changed only for the convenience of implementation from the perspective of process.

[0072] Embodiment 4:

[0073] The main contents of this embodiment are the same as those of embodiments 1 to 3, wherein see Figure 2 and Figure 3 The large end cylindrical surface 103 of the inner ring 1 is in interference contact with the sealing lip of the sealing ring 2. The outer circle of the sealing ring 2 is matched with the outer circle surface or inner hole of the body 301 of the outer rib 3.

[0074] Embodiment 5:

[0075] The main contents of this embodiment are the same as those of embodiments 1 to 4, wherein the sealing ring 2 is fastened to the outer rib 3 by means of screws 7 .

[0076] Embodiment 6:

[0077] The main contents of this embodiment are the same as those of embodiments 1 to 5. Fig. 20 Due to technological requirements, the outer ring 5 can be divided into two separate symmetrical parts.

[0078] Embodiment 7:

[0079] Since the contact angles of the first, second, and third generation wheel hub units of automobiles are mostly between 13° and 36°, the heat generation is huge and the grease needs to be replaced regularly. However, since the sealing ring cannot be removed, the grease of the first, second, and third generation maintenance-free wheel hub units cannot be replaced, which greatly reduces the maintenance-free mileage. In this embodiment, the low-energy consumption and long-life double-row tapered roller bearings described in any one of embodiments 1 to 6 are used for wheel hub bearings of passenger cars, commercial vehicles, or rail transit vehicles. The contact angle a of the bearing is selected to be 1° to 3°, and its heat generation is greatly reduced compared to the existing wheel hub bearings, and the evaporation, oxidation, and aging rates of the grease are greatly reduced, and the bearing life is correspondingly greatly extended.

[0080] The following compares the wheel hub bearings of passenger cars, commercial vehicles, and rail transit vehicles, which have a huge market scale, with the bearings of this embodiment, and introduces in detail the temperature rise and energy consumption of these bearings.

[0081] Existing passenger car wheel hub bearings widely use the first, second and third generation hub units, most of which are based on double row angular contact ball bearings as the basic structure, and the most common contact angle is 36° (see Fig.16 );

[0082] Existing commercial vehicle wheel hub bearings widely use two single-row tapered roller bearings, or the first and second generation double-row tapered roller bearing hub units. Whether it is a single-row or double-row hub bearing, the most common internal contact angle is 15° (see Figure 4 );

[0083] The vast majority of existing rail transit vehicles, whether it is the wheelset bearings of ordinary freight and passenger trains, or the axle box bearings of subway and high-speed rail EMUs, are double-row tapered roller bearings, and the most common internal contact angle is 10° (see Figure 6 ), the force analysis diagram of these three types of motor vehicle hub bearings under the condition of 2Qa pure radial load is shown in Fig.16 and 10 , the derived axial load generated inside is as follows: 2Qa*tan36°=1.44Qa, 2Qa*tan15°=0.54Qa, 2Qa*tan10°=0.35Qa, the percentage of derived axial load to pure radial load is: 1.44Qa / 2Qa*100%=72%, 0.54Qa / 2Qa*100%=27%, 0.35Qa / 2Qa*100%=18%;

[0084] See also Fig. 9 and Fig.11 The force analysis diagram of the low energy consumption and long life double row tapered roller bearing of this embodiment is shown in FIG. Fig.11 . Taking the most commonly used contact angle a of 3° as an example, the derived axial load generated inside is as follows: 2Qa*tan3°=0.1Qa, and the percentage of the derived axial load to the pure radial load is: 0.1Qa / 2Qa*100%=5%. Through the above calculation, it can be concluded that the bearing of this embodiment reduces the percentage of the derived axial load to the effective load applied to the bearing by various existing motor vehicles from 72% to 18% to about 5%, greatly reducing the derived axial load; according to the first law of thermodynamics, that is, the law of conservation of energy, 100% of the work done by these derived axial loads is converted into heat.

[0085] Due to the different working conditions of passenger cars and commercial vehicles, the structure of this low-energy consumption and long-life double-row tapered roller bearing and the structure after upgrading are also different:

[0086] A. This low energy consumption and long life double row tapered roller bearing is used in commercial vehicle axles. Fig.17 This is a schematic diagram of a second-generation low-energy consumption and long-life double-row tapered roller bearing. In this embodiment, the bearing integrates the outer ring and the wheel hub into one part, and uses bolts to fix the brake drum (disc) and the rim (or adapter plate) to the outer ring of the second-generation low-energy consumption and long-life double-row tapered roller bearing. Through such an optimized design, the process is simplified, the weight is reduced, and the cost is reduced. Fig.18 A schematic diagram of an upgraded second-generation low-energy-consumption and long-life commercial vehicle double-row tapered roller bearing; and Fig.17 The second generation of low energy consumption and long life double row tapered roller bearings has a different structure. Fig.18 The second generation of low-energy and long-life commercial vehicle double-row tapered roller bearings have threaded holes on both ends of the outer ring, so that the wheel rim (or adapter plate) can be fixed on the left with bolts, and the brake drum (disc) can be fixed on the right with bolts. This optimized design further reduces weight and costs.

[0087] B. Application of this low energy consumption and long life double row tapered roller bearing in passenger car wheel end assembly. Fig.19 This is a schematic diagram of the third generation of low energy consumption and long life passenger car double row tapered roller bearings. Fig.21 This is a schematic diagram of the fourth generation of low energy consumption and long life passenger car double row tapered roller bearings. Fig. 22 The schematic diagram of an upgraded version of the fourth-generation low-energy consumption and long-life passenger car double-row tapered roller bearing is a schematic diagram of an upgraded version of the fourth-generation low-energy consumption and long-life passenger car double-row tapered roller bearing. The upgraded version of the fourth-generation low-energy consumption and long-life passenger car double-row tapered roller bearing integrates the separate inner ring and universal joint cover of the fourth-generation low-energy consumption and long-life passenger car double-row tapered roller bearing into one part, so as to optimize the manufacturing process and reduce costs.

[0088] Embodiment 8:

[0089] For existing rail transit wheelset (or axle box) bearings, whether it is a double-row tapered roller bearing or a double-row cylindrical roller bearing, since the temperature of the inner ring is higher than that of the outer ring, a certain amount of clearance must be left to ensure that the bearing does not get stuck or stuck. In this embodiment, the low-energy consumption and long-life double-row tapered roller bearing described in any one of embodiments 1 to 6 is used for rail transit wheelset bearings or axle box bearings. The contact angle a of the bearing is selected to be 1° to 4°. On the one hand, a smaller contact angle greatly reduces the heat generation. On the other hand, due to the sliding friction between the two ribs of the outer ring and the rollers, the heat generated by the outer ring and the rollers is greater than that of the inner ring. However, since the heat dissipation condition of the outer ring is better than that of the inner ring, when the contact angle is selected appropriately, it can be ensured that the inner and outer rings and the rollers have the same temperature rise. When the original clearance value of a low-energy consumption and long-life double-row tapered roller bearing of the present embodiment is properly designed, so that the clearance value after installation is between 0 and a very small value, the low-energy consumption and long-life double-row tapered roller bearing is always in the best working state of approximately 0 clearance, and the maintenance-free mileage and life are greatly extended; not only that, when the grease needs to be replaced, the existing axle box (or wheelset) bearing still needs to replace the sealing cover and retainer even if every part is intact; due to the advanced structural design of the bearing of the present embodiment, if the sealing cover and retainer are not damaged, there is no need to replace them, saving huge costs.

[0090] The existing rail transit wheelset (axle box) bearings have two structures: double-row tapered roller bearings and double-row cylindrical roller bearings, of which double-row tapered roller bearings are the main ones. Since the wheelset (or axle box) bearings are subjected to heavy loads and high speeds, the biggest problem of these two bearings is that the temperature rise of the inner ring is higher than that of the outer ring, resulting in a certain amount of clearance during the design. In particular, it is necessary to ensure that the axle box bearings of high-speed trains cannot be "stuck" or "stuck" during long-distance operation. The axial design value of the clearance of the double-row tapered roller bearings of high-speed trains is 0.7 4-0.8mm. Since the contact angle of the high-speed train is 10°, the radial clearance value converted is between 0.26-0.28mm (0.26=2*0.74*tan10°, 0.28=2*0.8*tan10°). Since the outer ring is fixed, the outer raceway bears local load. Such a large clearance value causes super load in a very narrow area on the circumference of the outer raceway, causing the outer raceway to peel off prematurely. Since the roller and the inner ring bear cyclic load, the peeling ratio of the roller surface and the inner raceway is much smaller than that of the outer raceway. This embodiment changes the internal structure to change the parts that generate the most heat from the inner ring and roller to the outer ring and roller. Since the heat dissipation effect of the outer ring is greater than that of the inner ring, the inner and outer rings and rollers have the same temperature rise when working. When the clearance of the bearing after loading is between 0 and a small positive clearance, half of the area of ​​the inner and outer raceway circumference bears the load, and half of the number of rollers bears the load. In this way, the bearing has the strongest load-bearing capacity and the longest life. In addition, the existing double-row tapered roller bearings for rail transit (see Figure 8 ) is fixed by the interference fit between the outer circle of the frame and the inner hole of the outer ring. Since the frame thickness of the sealing cover is limited and the hardness is very low, even if other fixing and clamping processes are added, it is difficult to prevent the sealing cover from falling off and failing. In this embodiment, since the two end faces of the outer ring of the bearing have a certain thickness, the sealing cover is fixed to the end face of the outer ring by screws 7, thus reducing the probability of the sealing cover falling off to 0; not only that, when the bearing is overhauled, it is necessary to disassemble the sealing cover, and it is only necessary to unscrew the screws 7 and then tighten the screws to the threaded holes evenly distributed on the circumference of the bottom surface of the sealing cover. Since the bottom surface of the threaded hole is also in contact with the end face of the outer ring, the sealing cover can be pushed out. The advantage of this structural design is that the sealing cover can be disassembled intact and can continue to be used. Similarly, due to the advanced design of this embodiment, the retainer can also be disassembled intact and can continue to be used, and the cost reduction effect is significant.

[0091] Embodiment 9:

[0092] The existing fuel commercial vehicle drive axle main reducer assembly is mostly composed of a driving bevel gear and two single-row tapered roller bearings. This structure is complex and large in size. An adjustment gasket is required to control the clearance between the two single-row tapered roller bearings. The driving bevel gear is a stepped shaft with a certain length, which has poor precision, poor rigidity, and poor load-bearing capacity. Since there must be a clearance between the two single-row tapered roller bearings, the driving and driven bevel gears cannot mesh well. These are the root causes of noise and vibration in the main reducer. In this embodiment, the low-energy consumption and long-life double-row tapered roller bearing described in any one of embodiments 1 to 6 is used in the fuel commercial vehicle drive axle main reducer assembly.

[0093] The schematic diagram of the main reducer assembly of the fuel commercial vehicle drive axle using the low energy consumption and long life double row tapered roller bearing is shown in Fig.23 Compared with the existing main reducer assembly, it is no longer necessary to use an adjustment sheet to control the bearing clearance. Moreover, the clearance of the low-energy consumption and long-life double-row tapered roller bearing after installation is between 0 and a tiny positive clearance. This is different from the existing two bearings where sufficient clearance must be left. Because the area with the highest heat generation in the existing bearing is located between the large rib of the inner ring and the large end face of the roller, the temperature of the inner ring and the roller is higher than that of the outer ring. Because the two inner rings and the active bevel gear shaft are matched, the heat is transferred from the inner ring to the active bevel gear shaft. Since the active bevel gear shaft is inside the bearing seat, the heat can only be transferred through the small end of the active bevel gear shaft. This is why the temperature of the inner ring and the roller is much higher than that of the outer ring. The expansion amount is greater than that of the outer ring. In order to avoid sticking or jamming, sufficient clearance must be left between the two bearings. The area with the highest heat generation of the low-energy consumption and long-life double-row tapered roller bearing is located between the large rib of the outer ring and the large end face of the roller. Since the surface area of ​​the outer circle of the outer ring is about twice the surface area of ​​the inner hole of the inner ring, and the outer side of the outer circle is the bearing seat, the heat generated by the outer ring and the roller can be easily transferred to the air through the bearing seat, so that the temperature difference between the inner and outer rings and the rollers of the bearing of this embodiment is greatly compressed compared with the existing structure, and the temperature of the outer ring and the roller is slightly higher than that of the inner ring. In this way, the low-energy consumption and long-life double-row tapered roller bearing is always in an approximately optimal working state with small clearance, and will never get stuck or jammed.

[0094] Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments, or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A low energy consumption and long life double row tapered roller bearing, characterized by: The double-row tapered roller bearing comprises two inner rings (1), two sealing rings (2), two outer ribs (3), two retainers (4), an outer ring (5) and two rows of tapered rollers (6); An inner raceway (101) is arranged on the circumferential outer circle of the middle section of the two inner rings (1); the inner raceway (101) is in the shape of a conical surface; the portion of the inner ring (1) located at the small end of the inner raceway (101) is marked as a small head, and the portion located at the large end of the inner raceway (101) is marked as a large head; a cylindrical surface (102) is arranged on the outer wall of the small head, and a cylindrical surface (103) is arranged on the outer wall of the large head; the small heads of the two inner rings (1) are in contact with each other; The inner hole of the outer ring (5) comprises two outer raceways (501), and a cylindrical section (502) is provided between the two outer raceways; the outer raceways (501) are in the shape of a conical surface; the small diameter ends of the two outer raceways (501) are connected to the cylindrical section (502); The outer rib (3) comprises an outer rib body (301) and a step portion (302); the outer rib body (301) is an annular structure as a whole; the outer rib body (301) is arranged at both ends of the outer ring (5); the step portion (302) is arranged on the inner ring surface of the outer rib body (301); the step portion (302) has a working surface that is in close contact with the spherical base surface (601) of the tapered roller (6); the outer ring (5) is sleeved on the outer side of the inner ring (1); the outer raceway (501), the inner raceway (101) and the step portion (302) together enclose a friction working portion; The retainer (4) is arranged in the friction working part; a tapered roller (6) is arranged in a window of the retainer (4); the tapered roller (6) rolls in the friction working part; the retainer (4) guides the tapered roller (7) to rotate along the outer raceway (501), the inner raceway (101) and the step portion (302); the tapered surface of the tapered roller (6) contacts the inner raceway (101) and the outer raceway (501), and the ball base surface (601) contacts the step portion (302); The two sealing rings (2) seal the bearing from both sides of the bearing respectively.

2. A low energy consumption and long life double row tapered roller bearing according to claim 1, characterized in that: The semi-cone angle of the outer raceway (501) is selected from 1° to 45°.

3. A low energy consumption and long life double row tapered roller bearing according to claim 1, characterized in that: The outer ring (5) and the outer rib (3) are of an integral structure or a split structure.

4. A low energy consumption and long life double row tapered roller bearing according to claims 1 to 3, characterized in that: The cylindrical surface (103) contacts the sealing lip of the sealing ring (2); the outer circle of the sealing ring (2) matches the outer annular surface or the inner annular surface of the outer rib body (301).

5. A low energy consumption and long life double row tapered roller bearing according to claim 4, characterized in that: The sealing ring (2) is fastened to the outer rib (3) by means of screws (7).

6. The low energy consumption and long life double row tapered roller bearing according to claim 1, characterized in that: The outer ring (5) can be made into two symmetrical parts.

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