Low-energy-consumption long-service-life bearing

Abstract

The utility model discloses a bearing with low energy consumption and long service life. The bearing comprises an inner ring, an outer flange, a retainer, an outer ring, a small flange and a tapered roller, one end of the inner ring is a small-head end, a small flange is sleeved on the small-head end, the other end of the inner ring is a large-head end, and an inner raceway is arranged between the large-head end and the small-head end. An inner hole of the outer ring comprises an outer raceway section and a cylindrical section, and an outer flange is further arranged on the side, close to the outer raceway section, of the outer ring. In the assembly state, the inner ring is located in an inner hole of the outer ring, and the inner raceway, the outer raceway and the step part form a friction working area. A retainer is arranged in the working area, the tapered roller is located in a retainer window, and the retainer drives the roller to rotate along the inner raceway, the outer raceway and the step portion during working. The bearing has the advantages of being small in number of parts, good in assembly 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, ultra-long in service life, integrated, free of pre-tightening all the time, zero in clearance and the like, and has the advantages of improving the efficiency of a transmission system, saving energy, reducing emission and the like.

Description

Technical Field

[0001] The utility model relates to the field of rolling bearings, in particular to a low-energy-consumption and long-life bearing. Background Art

[0002] With the rapid development of modern industry, bearings, as core components in mechanical transmission mechanisms, are increasingly being given more stringent functions, such as greater loads, faster speeds, longer lifespans, and higher rigidity. In addition, higher requirements are placed on bearings in terms of transmission efficiency, noise, vibration, temperature rise, price, energy conservation, and environmental protection. Taking into account the requirements for bearings based on the above factors, the main purpose is to reduce operating costs, improve energy utilization, extend the service life of bearings, and contribute to cost savings, energy conservation, and emission reduction. Existing bearings, especially motor vehicle wheel hub bearings, have the following problems that need to be solved urgently:

[0003] 1. Spalling of the bearing working surface: Due to the unreasonable design of the bearing and the fact that high-speed, heavy-load bearings generally use roller bearings, the temperature of the bearing will inevitably rise under the dual effects of high speed and heavy load. Moreover, the temperature rise of each component of the bearing is different. To prevent the bearing from "stuck" or even "seized" when the temperature rises to a certain level, the bearing must be provided with clearance, and the bearing must be guaranteed to operate smoothly under extreme temperature rise conditions. Although sufficient clearance solves the "stuck" problem, it also brings an equally serious problem, namely spalling of the bearing working surface. The existence of bearing clearance makes it impossible for the various components within the bearing to bear the load evenly and uniformly. For example, the raceway of the stationary inner or outer ring is divided into load and non-load areas. The entire raceway working surface only bears the load in the local load area, and spalling of the working surface occurs in this area. This is caused by stress concentration. Due to the existence of clearance, the inner and outer raceways and rollers actually bear excessive loads rather than a uniform load, which greatly shortens the bearing life.

[0004] 2. Temperature rise and ablation problems of bearing parts: 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, deep groove ball bearings or cylindrical roller bearings used in motors 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. For example, if there is clearance in the bearings, there will be slight collisions between the rolling elements and the retainers and the inner and outer raceways, which will cause temperature rise. In addition, in order to bear a certain axial force, the existing motor vehicle hub bearings are designed with an angular contact structure inside. Under normal Under working conditions, the wheel hub bearings of motor vehicles only bear pure radial loads and axial loads only when turning. However, due to their internal angular contact structure, even if the motor vehicle travels in a straight line for more than 99.99% of the time, additional harmful 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 grease to evaporate and oxidize. Over time, the grease will age, solidify, and fail, causing increased friction and wear inside the bearing, and ultimately leading to bearing burnout and scrap.

[0005] 3. High energy consumption problem: From the analysis in the second paragraph above, it can be seen that almost all motor vehicle wheel hub bearings are angular contact bearings. When running in a straight line, they will generate additional harmful derived axial loads. These derived axial loads will inevitably generate friction torque. If the motor vehicle is to run normally, it must overcome this derived friction torque, which will consume energy. The additional increase in energy consumption also increases the operating cost of the motor vehicle.

[0006] 4. Bearing clearance: Bearing clearance significantly affects bearing life, temperature rise, noise, vibration, and other factors. Existing structures make it impossible to adjust bearing clearance to zero in design or process, resulting in reduced performance and shortened life, requiring regular overhauls and maintenance. Utility Model Content

[0007] The utility model aims to provide a low-energy-consumption and long-life bearing, which comprises an inner ring, an outer rib, a retainer, an outer ring, a small rib and a plurality of tapered rollers.

[0008] The inner ring as a whole is a structure with a conical middle and cylindrical ends and a cylindrical hole inside. The end with a smaller radius of the cylindrical segment at both ends is marked as the small head end, and the end with a larger radius is marked as the large head end. The area between the large head end and the small head end is marked as the inner raceway.

[0009] The small rib is a hollow cylindrical structure, which is sleeved on the outer cylindrical surface of the small head end of the inner ring. A working surface is provided on the end surface of the small rib facing the large head end of the inner ring.

[0010] The outer ring is a hollow rotating body. The inner hole of the outer ring includes an outer raceway section and a cylindrical section. The inner hole of the outer raceway section is conical in shape. The end with the smaller radius of the outer raceway section is marked as the small diameter end, and the end with the larger radius is marked as the large diameter end. The small diameter end is connected to the cylindrical section.

[0011] The outer rib is an annular structure as a whole, including an outer rib body and a step portion. One end of the outer rib body is connected to the large diameter end of the outer raceway section, and the inner side wall at the connection position is provided with an annular step portion.

[0012] When the inner ring and the outer ring are assembled, the inner ring is located in the inner hole of the outer ring, and the inner raceway, the outer raceway and the step portion form a friction working area.

[0013] A retainer is installed in the friction working area.

[0014] The plurality of tapered rollers are located in the friction working area and are evenly separated by retainer windows. In the working state, the tapered rollers rotate in the friction working area against the steps of the inner raceway, the outer raceway and the outer rib.

[0015] Furthermore, the outer diameter of the inner raceway segment gradually increases from the small end to the large end.

[0016] Furthermore, the semi-cone angle of the outer raceway is a=1° to 9°.

[0017] Furthermore, the tapered roller is a cone-shaped structure, and the tapered surface of the tapered roller is in contact with the inner raceway and the outer raceway with zero clearance.

[0018] Furthermore, the tapered roller is a cone-shaped structure, and the end with a larger radius is marked as a spherical base surface, and the spherical base surface contacts the step portion of the outer rib.

[0019] Furthermore, the inner ring and the small rib are an integrally formed structure.

[0020] Furthermore, the small rib and the inner ring are two parts.

[0021] A plurality of screw holes are provided on the outer cylindrical surface of the small rib. When the small rib is assembled, cylindrical pins with interference fit or overfit with the screw holes are placed in the screw holes. The small rib is axially positioned and locked on the inner ring through the set screw and the thread on the end of the cylindrical pin away from the set screw.

[0022] Furthermore, the outer ring and the outer rib are two parts or an integrally formed structure.

[0023] Furthermore, the bearing further includes an outer oil seal and an inner oil seal.

[0024] The outer oil seal is arranged between the inner ring big head end and the outer rib, has an interference fit with the inner hole of the outer rib body, and has an interference sealing fit with the outer cylindrical surface of the inner ring big head end.

[0025] The inner oil seal is arranged between the small rib and the outer ring cylindrical section, has an interference fit with the inner hole of the outer ring cylindrical section, and has an interference sealing fit with the outer cylindrical surface of the small rib.

[0026] The technical effect of the present invention is unquestionable, and the beneficial effects of the present invention are as follows:

[0027] The utility model has the advantages of small number of parts, good assembly performance, compact structure, large load, low cost, low temperature rise, low noise, low friction torque, super energy saving, zero clearance during normal operation, ultra-long life, high strength, high torque rigidity, high reliability, and high stability. It is widely used to replace motor vehicle wheel hub bearings and many mechanisms that require control of bearing clearance. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 This is a schematic diagram of a low-energy-consumption and long-life bearing structure;

[0029] Figure 2 Schematic diagram of the outer ring structure;

[0030] Figure 3 Schematic diagram of the inner ring structure;

[0031] Figure 4 Schematic diagram of the small rib structure;

[0032] Figure 5 Schematic diagram of the retainer structure;

[0033] Figure 6 Schematic diagram of roller structure;

[0034] Figure 7 Schematic diagram of the connection between the inner ring and the small rib;

[0035] Figure 8 This is the working principle diagram of the bearing without adjustment (control) and zero clearance;

[0036] Figure 9 This is the axial force transmission route diagram when the bearing is subjected to axial force in the left direction;

[0037] Figure 10 This is the axial force transmission route diagram when the bearing is subjected to rightward axial force;

[0038] Figure 11 Schematic diagrams of the most typical internal structure and force analysis of the first, second, and third generation wheel hub units for existing passenger cars;

[0039] Figure 12This is a schematic diagram of the internal heating parts of existing double-row tapered roller bearing products;

[0040] Figure 13 This is a schematic diagram of existing rail transit wheelset (axle box) bearing products;

[0041] Figure 14 This is a graph showing the change in axial clearance of the bearing described in this application under conditions of thermal expansion and contraction;

[0042] Figure 15 The force analysis diagram for each single row of the existing double-row tapered roller bearing;

[0043] Figure 16 This is a force analysis diagram of a low-energy-consumption and long-life bearing;

[0044] Figure 17 This is a schematic diagram of the internal heating parts of a low-energy-consumption and long-life bearing;

[0045] Figure 18 Schematic diagram of bearing axial clearance and relative bearing life;

[0046] Figure 19 This is a schematic diagram of the application of the bearing described in this application on the wheel end of the steering axle of a commercial vehicle;

[0047] Figure 20 A schematic diagram of the application of a low-energy-consumption, long-life bearing with a different internal structure on the wheel end of a commercial vehicle steering axle;

[0048] Figure 21 This is a schematic diagram of the application of the bearing described in this application on the wheel end of the drive axle of a commercial vehicle;

[0049] Figure 22 A schematic diagram of the application of a low-energy-consumption, long-life bearing with a different internal structure on the wheel end of a commercial vehicle drive axle;

[0050] Figure 23 A schematic diagram of the application of a low-energy-consumption, long-life bearing with a different internal structure on the wheel end of a passenger vehicle, namely the third-generation wheel hub unit assembly;

[0051] Figure 24 A schematic diagram of the application of a low-energy-consumption, long-life bearing with a different internal structure on the wheel end of a passenger vehicle, namely the fourth-generation wheel hub unit assembly;

[0052] Figure 25 This is a schematic diagram of the existing rail transit gearbox structure;

[0053] Figure 26 This is a schematic diagram of the application of a low-energy-consumption and long-life bearing with a different internal structure in a rail transit gearbox.

[0054] In the figure: inner ring 1, inner raceway 101, small head end 102, large head end 103, outer oil seal 2, outer rib 3, outer rib body 301, step portion 302, retainer 4, outer ring 5, small rib 6, working surface 601, tapered roller 7, tapered roller heating part 703, inner oil seal 8, cylindrical pin 9, set screw 10. Passenger vehicle wheel hub bearing outer ring 1101, passenger vehicle wheel hub bearing inner ring 1102, steel ball 1103, double-row tapered roller bearing outer ring 1201, double-row tapered roller bearing inner ring 1202, double-row tapered roller bearing roller 1203, double-row tapered roller bearing roller heating part 1204, existing rail transit wheelset (axle box) bearing outer ring 1301, existing rail transit wheelset (axle box) bearing inner ring 1302, existing rail transit wheelset (axle box) bearing roller 1303, commercial vehicle steering axle wheel end assembly hub 1401, steering knuckle 1402, external oil seal 1403, inner oil seal 1404, ABS ring gear 1405, brake disc 1406, rim adapter plate 1407, bearing outer ring and wheel hub integrated into one part 1408, commercial vehicle drive axle wheel end assembly hub 1501, half shaft 1502, shaft tube 1503, brake drum 1504, rim 1505, bearing outer ring and commercial vehicle drive axle hub integrated into one part 1506, universal joint cover 17, cylindrical roller bearing 18, tapered roller bearing 19, four-point contact ball bearing 20, input shaft 21, output shaft 22, low-energy consumption and long-life bearing 23. DETAILED DESCRIPTION

[0055] The present invention will be further described below with reference to the following embodiments. However, it should not be understood that the scope of the present invention is limited to the following embodiments. Without departing from the above technical concept of the present invention, various substitutions and modifications based on common technical knowledge and customary means in the field should be included in the scope of protection of the present invention.

[0056] Example 1:

[0057] A low-energy-consumption and long-life bearing comprises an inner ring 1, an outer rib 3, a retainer 4, an outer ring 5, a small rib 6 and a plurality of tapered rollers 7.

[0058] The inner ring 1 as a whole is a rotating body structure with a conical middle, cylindrical ends and a hollow interior. The end with a smaller radius of the cylindrical segment at both ends is marked as a small head end 102, and the end with a larger radius is marked as a large head end 103. The area between the large head end 103 and the small head end 102 is marked as an inner raceway 101 section.

[0059] The small rib 6 is a hollow cylindrical structure, which is mounted on the outer cylindrical surface of the inner ring small head end 102 . A working surface 601 is provided on the end surface of the small rib 6 facing the large head end 103 .

[0060] The outer ring 5 is a hollow rotating body. The inner hole of the outer ring 5 includes an outer raceway 501 and a cylindrical section 502. The inner hole of the outer raceway 501 is conical in shape. The end with the smaller radius of the outer raceway 501 is designated as the small-diameter end, and the end with the larger radius is designated as the large-diameter end. The small-diameter end is connected to the cylindrical section 502.

[0061] The outer rib 3 is an annular structure, comprising an outer rib body 301 and a step portion 302. One end of the outer rib body 301 is connected to the large diameter end of the outer raceway 501, and an annular step portion 302 is provided on the inner side of the connection position.

[0062] When the inner ring 1 and the outer ring 5 are assembled together, the inner ring 1 is located in the inner hole of the outer ring 5, so that the inner raceway 101, the outer raceway 501 and the step portion 302 form a friction working area;

[0063] A retainer 4 is installed in the friction working area.

[0064] The tapered rollers 7 are located within the retainer 4 window in the friction working area and are evenly spaced apart by the retainer 4. During operation, the retainer 4 drives the tapered rollers 7 to rotate within the friction working area against the inner raceway 101, the outer raceway 501, and the stepped portion 302 of the outer rib.

[0065] Example 2:

[0066] The main structure of this embodiment is the same as that of embodiment 1. Furthermore, the outer diameter of the inner raceway 101 section gradually increases from the small end 102 to the large end 103.

[0067] Example 3:

[0068] The main structure of this embodiment is the same as any one of Embodiments 1 to 2. Furthermore, the semi-cone angle of the outer raceway 501 is a=1° to 9°.

[0069] Example 4:

[0070] The main structure of this embodiment is the same as any one of Embodiments 1 to 3. Furthermore, the semi-cone angle of the outer raceway 501 is a=1°.

[0071] Example 5:

[0072] The main structure of this embodiment is the same as any one of Embodiments 1 to 3. Furthermore, the semi-cone angle of the outer raceway 501 is a=9°.

[0073] Example 6:

[0074] The main structure of this embodiment is the same as any one of embodiments 1 to 5. Furthermore, the tapered roller 7 is a conical structure, and the conical surface of the tapered roller 7 is in contact with the inner raceway 101 and the outer raceway 501 with zero clearance.

[0075] Example 7:

[0076] The main structure of this embodiment is the same as any one of Embodiments 1 to 6. Furthermore, the tapered roller 7 is a conical structure, and the end with a larger radius is marked as a spherical base surface 701 , and the spherical base surface 701 is in contact with the step portion 302 .

[0077] Example 8:

[0078] The main structure of this embodiment is the same as any one of Embodiments 1 to 7. Furthermore, the inner ring 1 and the small rib 6 are an integrally formed structure.

[0079] Example 9:

[0080] The main structure of this embodiment is the same as any one of Embodiments 1 to 7. Furthermore, the small rib 6 and the inner ring 1 are two parts.

[0081] A plurality of screw holes are provided on the outer cylindrical surface of the small rib 6. When the small rib 6 is mounted on the outer cylindrical surface of the small head end 102 of the inner ring, a cylindrical pin with an interference fit or an overfit with the screw hole is placed in the screw hole, and the cylindrical pin is pushed to move in the screw hole by the set screw. The small rib 6 is axially positioned and locked on the inner ring 1 by the thread on one end of the cylindrical pin away from the set screw.

[0082] Example 10:

[0083] The main structure of this embodiment is the same as any one of the embodiments 1 to 7 and 9. Furthermore, the small rib 6 is mechanically fixed to the outer cylindrical surface of the small head of the inner ring 1. In this embodiment, the parts diagram of the small rib 6 is shown in FIG. Figure 4 The inner hole is positioned and fixed on the outer cylindrical surface of the small head of the inner ring 1 by means of threads or interference fit.

[0084] One of the most common positioning and fixing methods is to fix the small end face of the inner ring 1 to the small rib 6 (see Figure 7 ).

[0085] The other is that the small rib 6 of the low energy consumption and long life bearing is fixed on the outer cylindrical surface of the small head end 102 of the inner ring 1 through an internal thread (see Figure 17), several screw holes are drilled in the radial direction of the small rib 6, and there is a cylindrical pin inside the screw hole. There is a small interference fit or transition fit between the cylindrical pin and the screw hole. Before turning the internal thread of the small rib 6, use a set screw to push the cylindrical pin to move in the screw hole, ensure that the cylindrical pin slightly protrudes from the inner hole, and then use a thread cutter to turn the internal thread hole of the small rib 6. When the bearing needs to remove the roller 7 and the retainer 4, first loosen the set screw, and the cylindrical pin and the outer thread 102 of the small head of the inner ring 1 are no longer locked. Unscrew the small rib 6, and the roller 7 and the retainer 4 slide out of the inner raceway 101 of the inner ring together. Clean the roller 7, retainer 4 and the inner ring 1 separately. After checking that everything is correct, assemble the roller 7 and the retainer 4 to the inner raceway 101 of the inner ring 1, screw the small rib 6 onto the outer thread 102 of the small head of the inner ring 1, tighten the set screw, and the small rib 6 is firmly fixed on the outer thread 102 of the small head of the inner ring 1.

[0086] The third type is that the small rib 6 of the low energy consumption and long life bearing is fixed on the outer cylindrical surface of the small head end 102 of the inner ring 1 through an internal thread (see Figure 1 ), in order to prevent the small rib 6 from loosening, thread locking glue can be applied between the threads, or the small rib 6 can be fixed to the outer cylindrical surface of the small head end 102 of the inner ring 1 by other means.

[0087] In fact, due to the advantages of ultra-long maintenance-free period, ultra-long life, high rigidity, high reliability and high stability of this low-energy-consumption and long-life bearing, the maintenance cycle of the bearing is greatly extended.

[0088] Example 11:

[0089] The main structure of this embodiment is the same as any one of Embodiments 1 to 10, and the outer ring 5 and the outer rib 3 are two parts.

[0090] Example 12:

[0091] The main structure of this embodiment is the same as any one of Embodiments 1 to 10, and the outer ring 5 and the outer rib 3 are an integrally formed structure.

[0092] Example 13:

[0093] The main structure of this embodiment is the same as any one of Embodiments 1 to 12, and the bearing further includes an outer oil seal 2 and an inner oil seal 8.

[0094] The outer oil seal 2 is arranged between the inner ring big head end 103 and the outer rib 3 , and has an interference fit with the inner hole of the outer rib body 301 and an interference sealing fit with the outer cylindrical surface of the inner ring big head end 103 .

[0095] The inner oil seal 8 is arranged between the small rib 6 and the outer cylindrical section 502 , and has an interference fit with the inner hole of the outer cylindrical section 502 and an interference sealing fit with the outer cylindrical surface of the small rib 6 .

[0096] Example 14:

[0097] The main structure of this embodiment is the same as any one of Embodiments 1 to 13. Furthermore, the inner hole at the cylindrical section 502 is cylindrical in shape.

[0098] Example 15:

[0099] The main structure of this embodiment is the same as any one of embodiments 1 to 14. Furthermore, a low-energy consumption and long-life bearing includes an inner ring 1, an outer oil seal 2, an outer rib 3, a retainer 4, an outer ring 5, a small rib 6, a tapered roller 7 and an inner oil seal 8.

[0100] The outer conical surface of the middle section of the inner ring 1 is the inner raceway 101. The portion of the inner ring 1 at the left end of the inner raceway 101 is marked as the small end, and the portion at the right end is marked as the large end. The outer circle of the small end is the cylindrical surface 102. The inner raceway 101 is conical.

[0101] The small rib 6 is an annular structure and is sleeved on the cylindrical surface 102. A working surface 601 is provided on the end surface of the small rib 6 facing the inner raceway 101.

[0102] The inner hole of the outer ring 5 is marked as an outer raceway 501 and a cylindrical section 502 from the outer or small end to the inner end. The outer raceway 501 is in a conical shape. The small diameter end of the outer raceway 501 is connected to the cylindrical section 502.

[0103] The outer rib 3 includes an outer rib body 301 and a step portion 302. The outer rib 3 is arranged on the outer end side of the outer ring 5. The step portion 302 is located between the small end of the outer ring 5 and the outer rib body 301.

[0104] The outer ring 5 is coaxially mounted on the outer side of the inner ring 1. The outer raceway 501, inner raceway 101, small rib 6, and step 302 together form a friction working area. The retainer 4 is positioned within the friction working area. The retainer 4 has windows containing tapered rollers 7, which are positioned within the friction working area. The retainer 4 drives the tapered rollers 7 to rotate along the inner and outer raceways. The tapered surfaces of the tapered rollers 7 contact the inner raceway 101 and outer raceway 501, while the spherical base surfaces 701 contact the step 302.

[0105] The outer oil seal 2 is positioned in the gap between the outer cylindrical surface of the large end 103 of the inner ring 1 and the outer rib 3. The outer oil seal 2 is positioned on the outer end. The outer diameter of the outer oil seal 2 forms an interference fit with the inner bore of the outer rib body 301, while the lip of the outer oil seal 2 forms an interference, sealing fit with the outer cylindrical surface 103 of the large end of the inner ring 1.

[0106] The inner oil seal 8 is positioned in the gap between the small rib 6 and the inner cylindrical section 502 of the outer ring 5. The inner oil seal 8 is positioned on the inner end. The outer diameter of the inner oil seal 8 forms an interference fit with the inner bore of the cylindrical section 502, while the lip of the inner oil seal 8 forms an interference, sealing fit with the outer diameter of the small rib 6.

[0107] Example 16:

[0108] The main structure of this embodiment is the same as any one of Embodiments 1 to 15. Furthermore, it is well known that, in theory, when the bearing clearance is 0, the rolling bearing is in the optimal operating state. However, in actual operation, for transmission mechanisms with heavy loads and axial loads, tapered roller bearings are generally used for support. Currently, due to designers' lack of understanding of the actual operating conditions of bearings, the designed bearings have the problem of large temperature rise. Moreover, the temperature rise of each component of the bearing varies. In most cases, the temperature rise of the inner ring and roller is higher than that of the outer ring. This is because there is sliding friction between the spherical base surface of the roller and the large rib of the inner ring. The large sliding friction coefficient generates more frictional heat and a large temperature rise. In order to prevent the bearing temperature from rising to a certain level and causing "stuck" or even "seizure", clearance must be left in the bearing. The existence of clearance seriously affects the load state of the bearing, causing the roller and the raceways of the inner and outer rings to always bear uneven and non-uniform loads, leading to a series of problems such as working surface spalling, noise, vibration, temperature increase, and shortened service life. This seems to be a vicious circle, but the root cause is that the designers did not really design according to the actual operating conditions of the bearings during the design phase.

[0109] The utility model is a low-energy consumption, long-life bearing, which is mainly designed to solve the problem of needing to adjust and maintain a certain amount of bearing clearance on existing equipment, as well as the need to control the bearing clearance during the production stage of the bearing. The current situation is that the hub bearings of all motor vehicles such as cars, tractors, ordinary trains, subways and high-speed trains need to control the clearance, and the bearings in parts such as high-speed trains and subway gearboxes also need to control the clearance; therefore, the problem to be solved by the utility model has a wide range of commonalities, that is, without the need to adjust, control and maintain a certain amount of clearance during the production and assembly stages, the working clearance of the bearing is always 0, that is, the bearing is always in the best working condition.

[0110] The working principle of this low energy consumption and long life bearing with zero clearance:

[0111] The low energy consumption and long life bearing of the utility model has an internal structure that determines that no adjustment or pre-tightening is required and the clearance is always at 0 (see Figure 8), for the convenience of explaining the problem, only three parts that affect the bearing clearance are retained, and the other parts not related to the clearance are deleted. Since the weight and wind resistance of all motor vehicles are applied to the outer circle of the outer ring (or inner ring) in the form of radial load, the outer circle transfers the radial load to the outer raceway, and the outer raceway transfers the load to the roller. This radial force generates a derived axial force on the outer raceway. The radial force and the derived axial force force the roller to move toward the big end (or the right side) of the trumpet formed by the outer raceway and the inner raceway. When the spherical base surface 701 of the roller moves to the end face of the step portion 302 of the outer rib, the clearance between the spherical base surface of the roller in the axial direction and the end face of the step portion of the outer rib is 0; the radial load makes the radial clearance between the conical surface of the roller and the inner raceway and the outer raceway also 0. Regardless of whether the motor vehicle is stopped or in motion, as long as there is weight on the outer ring of the bearing, the bearing is always in the optimal working state of 0 clearance. The bearing's zero-clearance operating state ensures that the rolling elements and inner and outer raceways always bear the load evenly and uniformly, completely eliminating the situation where the rolling elements and inner and outer raceways could bear excessive loads locally due to clearance. This fundamentally eliminates the problem of premature spalling of the rolling elements and inner and outer raceways. Furthermore, because the bearing is always in a zero-clearance operating state, the temperature rise, noise, and vibration of the bearing itself are always kept to a minimum.

[0112] Example 17:

[0113] The main structure of this embodiment is the same as any of Embodiments 1 to 16. Furthermore, the low-energy consumption, long-life bearing of the present invention is a special single-row tapered roller bearing capable of simultaneously supporting radial loads and axial loads in two directions. In contrast, existing single-row tapered roller bearings can only support radial loads and axial loads in one direction, while existing double-row angular contact bearings can support radial loads and axial loads in two directions.

[0114] Although the utility model low energy consumption and long life bearing is a single row tapered roller bearing, it can bear radial load and axial load in two directions at the same time (see Figure 9 、 10 ), when the inner ring is subjected to an axial force in the left direction, the axial force is transmitted through the AA path, that is, inner ring-inner raceway-roller-outer raceway-outer ring; when the inner ring is subjected to an axial force in the right direction, the axial force is transmitted through the BB path, that is, inner ring-small rib-small end face of the roller-spherical base surface of the roller-step end face of the outer rib-outer rib (outer ring).

[0115] Example 18:

[0116] The main structure of this embodiment is the same as any one of Embodiments 1 to 17. Furthermore, the low-energy consumption and long-life bearing of the utility model can significantly reduce temperature rise and energy consumption.

[0117] With a huge global population of motor vehicles, existing wheel hub bearings for motor vehicles suffer from high temperature rise and energy consumption. This temperature rise reduces grease viscosity, accelerating evaporation and oxidation. Long-term temperature rise causes grease to solidify, age, and fail, increasing bearing friction and wear, which in turn shortens bearing life. High energy consumption also drives up vehicle operating costs. The following compares the bearings of this invention with wheel hub bearings for passenger cars, commercial vehicles, and wheelset (or axlebox) bearings for rail transit vehicles, which have a large market share. The temperature rise and energy consumption of these bearings are calculated in detail.

[0118] 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 Figure 11 );

[0119] Existing commercial vehicle wheel hub bearings widely use two single-row tapered roller bearings, or double-row tapered roller bearings of the first and second generation hub units. Whether it is a single-row or double-row hub bearing, the most common internal contact angle is 15° (see Figure 12 );

[0120] The vast majority of existing rail transportation vehicles, whether they are wheelset bearings for ordinary freight and passenger trains, or axlebox bearings for subway and high-speed trains, are double-row tapered roller bearings, with an internal contact angle of 10° being the most common (see Figure 13 );

[0121] The contact angle of a certain type of low energy consumption and long life bearing of the utility model is a=1.4° (see Figure 14 ). Through query, all the contact angle values ​​of the above four types of motor vehicle bearings are as follows:

[0122] Table 1: Four widely representative values ​​of internal contact angles of motor vehicle wheel hub bearings

[0123]

[0124] (1) Calculation of derived axial force of passenger car wheel hub bearings.

[0125] Although the development of passenger car wheel hub units has gone through the first, second and third generations, their internal structure has not changed. They are all designed with double-row angular contact balls, and their contact angle is generally 36° (see Figure 11 ), when the car is moving in a straight line, the wheel hub bearing mainly bears the pure radial load Q a , pure radial load Q a Acting on the outer ring, the outer ring Q a Evenly distribute it to two rows of steel balls, and the two rows of steel balls then put Q aTransfer to the two inner rings, so that each row of bearings bears 0.5Q a The radial load, due to the contact angle of 36 degrees, each row of ball bearings generates 0.5Q in the inner and outer grooves. a tan36°=0.36Q a The additional harmful derived axial load, the two column loads add up to 0.72Q a , the steel ball and the inner and outer channels generate 0.72Q respectively a The additional harmful derived axial load amounts to 72% of the total pure radial load applied to the four wheel hub bearings by the entire vehicle and wind resistance.

[0126] (2) Calculation of derived axial force of commercial vehicle wheel hub bearings.

[0127] Existing commercial vehicle wheel hub bearings are either two single-row tapered roller bearings or first and second generation double-row tapered roller bearing hub units (see Figure 12 ), when a pure radial force Q is applied to the outer ring a When the outer ring passes through the two rows of rollers, Q a The force is evenly transferred to the two inner rings, so as long as the force of one inner and outer raceway and roller is calculated, and then multiplied by 2, the force of the entire bearing is obtained. In this case, it can be further simplified and the two inner and outer raceways and two rows of rollers can be calculated as one inner and outer raceway and one row of rollers, which is equivalent to a single-row bearing bearing a pure radial force Q a , its force analysis is shown in Figure 15 According to the parameters listed in Table 1 above, the semi-cone angle a of the outer raceway of the bearing is 15°, the semi-cone angle b of the inner raceway is 11.4°, and the angle c of the large rib is 11.9°. When the outer ring is subjected to a pure radial force Q a When the outer ring transfers the pure radial force Q through the roller a The vertical and horizontal forces are applied to the inner ring raceway and rib respectively. The roller is in equilibrium under the action of the three forces of the inner and outer raceways and the large rib, so:

[0128] Q n -Q i -Q y =0 (1)

[0129] Q a -Q e +Q x =0 (2)

[0130] Among them, Q n =Q m sina, Q a =Q m cosa, Q i =Q b sinb,Qe =Q b cosb,Q x =Q z sinc,Q y =Q z cosc, substituting these six equations into equations (1) and (2) and simplifying them, we get:

[0131] Q b =Q m (sinasinc+cosacosc) / (sinbsinc+cosccosb) (3)

[0132] Q z =Q m (sinacosb-cosasinb) / (sinbsinc+cosccosb) (4)

[0133] Substituting the previous angle values ​​of a, b, and c into (3) and (4) yields:

[0134]

[0135] The radial force borne by the inner ring is:

[0136]

[0137] The axial force borne by the inner ring raceway is:

[0138] Q i =Q b sinb=Q m sinb=0.198Q m =0.198Q a / cos15°=0.21Q a

[0139] The axial force on the outer ring raceway is Q n =Q a taga=0.27Q a

[0140] The axial force on the large flange is Q y =Q z cosc=0.063Q m cos11.9°=0.06Q a

[0141] (3) Calculation of derived axial force of rail transit wheelset (axle box) bearings.

[0142] The existing rail transit wheel set (axle box) bearing is a double row tapered roller bearing (see Figure 13), when the EMU body applies a pure radial force Q to the outer ring a When the outer ring passes through the two rows of rollers, Q a The force is evenly transferred to the two inner rings. Since all the parameters of the two inner and outer raceways and the two rows of rollers are the same, it is only necessary to calculate the force of one inner and outer raceway and roller, and then multiply it by 2 to get the force of the entire bearing. In this case, it can be further simplified and the two inner and outer raceways and the two rows of rollers can be calculated as one inner and outer raceway and one row of rollers, which is equivalent to a single-row bearing bearing a pure radial force Q a , its force analysis is shown in Figure 15 According to the parameters listed in Table 1 above, the semi-cone angle a of the outer raceway of the bearing is 10°, the semi-cone angle b of the inner raceway is 8°, and the angle c of the large rib is 8.5°. When the outer ring is subjected to a pure radial force Q a When the outer ring transfers the pure radial force Q through the roller a Decomposed into vertical and horizontal forces applied to the inner raceway and rib respectively, the roller is in equilibrium under the action of these three forces: the inner and outer raceways and the large rib. Therefore, there are four equations (1), (2), (3), and (4) in Section (2). Substituting the angle values ​​of a, b, and c into equations (3) and (4) and simplifying them, we get:

[0143] Q b =Q m (sinasinc+cosacosc) / (sinbsinc+cosccosb)=Q m

[0144] Q z =Q m (sinacosb-cosasinb) / (sinbsinc+cosccosb)=0.035Q m

[0145] The radial force borne by the inner ring is:

[0146] Q e +Q x =Q b cosb+Q z sinc=0.99Q m +0.148×0.035Q m

[0147] =0.995Q a / cosa=1.01Q a

[0148] The axial force borne by the inner raceway is:

[0149] Q i =Qb sinb=Q m sinb=0.139Q m =0.139Q a / cos10°=0.14Q a

[0150] The axial force on the outer ring raceway is Q n =Q a taga=0.18Q a

[0151] The axial force on the large flange is Q y =Q z cosc=0.035Q m cosc=0.04Q a

[0152] (4) Calculation of the derived axial force of this low-energy-consumption and long-life bearing.

[0153] When the outer ring of this low energy consumption and long life bearing is subjected to pure radial force Qa, the outer ring transmits Qa to the inner ring through the rollers. The force analysis is shown in Figure 16 According to the parameters listed in Table 1 above, the semi-cone angle a of the outer raceway of the bearing is 1.4°, the semi-cone angle b of the inner raceway is 1°, and the angle c of the large rib is 1.37°. When the outer ring is subjected to a pure radial force Q a When the outer ring transfers the pure radial force Q through the roller a Decomposed into vertical and horizontal forces applied to the inner raceway and rib respectively, the roller is in equilibrium under the action of these three forces: the inner and outer raceways and the large rib. Therefore, there are four equations (1), (2), (3), and (4) in Section (2). Substituting the angle values ​​of a, b, and c into equations (3) and (4) and simplifying them, we get:

[0154] Q b =Q m (sinasinc+cosacosc) / (sinbsinc+cosccosb)=Q m

[0155] Q z =Q m (sinacosb-cosasinb) / (sinbsinc+coscccosb)=0.007Q m

[0156] The radial force borne by the inner ring is:

[0157]

[0158] The axial force borne by the inner ring raceway is:

[0159] Q n -Q y =Q m sina-Q z cosc=Q m (sina-0.007cosc)=0.017Q m =0.017Q a / cosa=0.017Q a

[0160] The axial force on the outer ring raceway is Q n =Q a taga=0.024Q a

[0161] The axial force on the outer flange is Q y =Q a cosc=0.007Q m cosc=0.007Q a

[0162] (5) Comparison of temperature rise and energy consumption of several bearings

[0163] The following conclusions can be drawn from the calculations in (1), (2), (3), and (4):

[0164] A. When the outer rings of the four bearings are subjected to pure radial force, the outer rings transmit almost the same radial force to the inner rings through the rollers, that is, Q e =Q a , the radial force borne by the rib is too small to be considered.

[0165] B. From Table 2, we can see the following facts: When the four bearings are subjected to the same pure radial load Q a In this case, passenger cars generated 0.72Q a Additional harmful derived axial loads, commercial vehicles generate 0.27Q a The additional harmful derived axial load, the rail transit wheel set (axle box) bearing generates 0.18Q a In addition to the harmful derived axial load, this low energy consumption and long life bearing produces 0.024Q a Additional harmful derived axial loads; The additional harmful derived axial loads generated by these four bearings account for 72%, 27%, 18% and 2.4% of the pure radial effective load borne by the bearings respectively. It can be seen that through innovative design, the patented bearing greatly reduces the additional harmful derived axial loads.

[0166] Table 2: The magnitude of the harmful derived axial force on the internal parts of the existing bearings and the bearings of the patentee's utility model, as well as the percentage of the harmful axial load to the effective load.

[0167]

[0168] These additional harmful derived axial loads generate a certain amount of friction F = μQ between the steel balls and the inner and outer raceways of ball bearings, and between the rollers and the inner and outer raceways and ribs of roller bearings. b (Q b Represents the additional harmful derived axial force borne by each part of the bearing, μ is the friction coefficient), according to the torque calculation formula T = Fr, r represents the distance from the point of action of the friction force to the center line of the bearing, the axial friction torque between the various parts inside the bearing can be calculated; according to the relationship between power and torque: P = Tω (P represents power, ω represents angular velocity), the power generated between the various parts inside the bearing can be calculated, and then according to the calculation formula of work and power: W = Pt (t represents time), the above three formulas are sorted out to obtain the following formula: W = Q b μrωt, 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. From this, we can draw the following conclusion: the temperature rise and energy consumption caused by the bearing bearing the additional harmful derived axial load are proportional to the derived axial load, friction coefficient, size, speed and running time borne by the bearing. Under the premise of the same friction coefficient, size, speed and running time, the only way to reduce the temperature rise and energy consumption is to reduce the additional harmful derived axial load Q b One of the innovative designs of this patented bearing is to significantly reduce the contact angle of the bearing, so that the additional harmful derived axial load Q borne by each part of the bearing is reduced to b It is reduced to the limit, resulting in a significant reduction in temperature rise and energy consumption, completely eliminating the root cause of "hot shaft" and "hot cut shaft" in the wheelset (axle box) bearings of rail transit vehicles, and completely eliminating the overheating problem in the wheel hub of motor vehicles.

[0169] C. Whether it is a wheel hub bearing for a commercial vehicle or a wheel set (axle box) bearing for a rail transit vehicle, the heating part 1204 is shown in the diagram when it is working. Figure 12In addition to the normal heat generated by the friction between the various parts of the bearing due to the radial force, the heat generated by the friction between the various parts due to the axial force is abnormal heat. Both theoretical analysis and experiments have verified that the part of the existing bearing that generates the most heat is between the ball base surface 701 of the roller and the outer rib 3. Because the ball base surface 701 of the roller and the outer rib 3 are sliding friction, the friction coefficient is much greater than the rolling friction coefficient; although the heat generated by the rolling friction between the inner and outer raceways and rollers due to the axial force is roughly the same, the outer ring has a surface area about twice that of the inner ring, and the outer ring is either exposed to the elements or exposed to the elements. When exposed to the air, or in the wheel hub or axle box, the heat can be easily dissipated or transferred. However, since the inner ring is installed on the axle, whether it is a solid shaft or a hollow shaft, the heat is not easy to dissipate. Therefore, the heat generated by the inner ring and the roller is much greater than that of the outer ring. In order to prevent the bearing from "stuck" or "stuck", the clearance can only be increased. This is the root cause of "hot shaft" and "thermal breakage" in rail transit wheelset (axle box) bearings; due to the abnormal temperature rise caused by long-term heating, the grease evaporates and oxidizes faster, and then ages and solidifies and fails, so motor vehicles always need to replace the grease frequently, which is the so-called maintenance.

[0170] In addition to the significant reduction in the additional harmful derived axial force discussed in Section B above, the low energy consumption and long life bearing has a more reasonable distribution of internal heat sources or temperature fields (see heating part 703). Figure 17 ), the outer rib of the low-energy consumption and long-life bearing moves from the inner ring to the edge of the outer ring, and the heat generated by the inner ring is less than the heat generated by the outer ring and the roller. Since the surface area of ​​the outer ring is about twice that of the inner ring, and the outer ring is either exposed to the air or in the wheel hub or axle box, the heat can be easily dissipated or transferred, so the heat dissipation effect is much better than that of existing bearings. In addition, since the rollers of the low-energy consumption and long-life bearing are always in contact with the inner and outer raceways, the heat on the inner ring can also be easily dissipated or transferred through the rollers and outer ring. Therefore, the temperature rise of the inner and outer rings and rollers is relatively low, and "stuck" or "stuck" will not occur.

[0171] Furthermore, temperature rise is significantly reduced, grease evaporation and oxidation are slowed or even eliminated, significantly extending bearing life and reducing the energy consumption required to drive the vehicle. It is worth noting that this low-energy, long-life bearing is suitable for wheel hubs in various motor vehicles, including automobiles, tricycles, motorcycles, agricultural machinery, tractors, and construction machinery. It is also suitable for installation in conventional freight and passenger trains, as well as for use as wheel set (axle box) bearings in subway and high-speed trainsets. It is also suitable for various high-speed, heavy-load applications, particularly those involving high axial forces and requiring controlled bearing clearance.

[0172] Furthermore, the oil film within this low-energy, long-life bearing is always in normal working order, significantly extending the life of the bearing and the lubricant. In many operating conditions, existing bearings, due to the presence of play, experience a situation where the load, which should be evenly and uniformly borne by all rolling elements and the inner and outer raceways, is instead subjected to localized overloads and even cyclic loads on some parts. When the overload exceeds the oil pressure generated between the rolling elements and the inner and outer raceways, an oil film cannot form between the rolling elements and the raceways, resulting in dry friction, which severely affects the bearing's lubrication, shortening the bearing's life and causing the lubricant to lose effectiveness. Since the load is evenly borne by all rolling elements in this low-energy, long-life bearing, the lubricant accumulates in the wedge-shaped gap between the rolling elements and the inner and outer raceways, generating oil pressure. When the oil pressure exceeds the load borne by the rolling elements, it lifts the rolling elements, forming an oil film between them and the raceways, significantly extending the life of the bearing and the lubricant.

[0173] Example 19:

[0174] The main structure of this embodiment is the same as that of Example 18. Furthermore, this low-energy consumption and long-life bearing is used in commercial wheel end assemblies.

[0175] As can be seen from Table 2, the contact angle inside the bearings of existing commercial vehicle wheel hub bearings, whether they are two single-row tapered roller bearings or first- and second-generation commercial vehicle wheel hub units, is mostly around 15°. This angle is designed to be too large, causing the existing wheel hub bearings to bear a large additional harmful derived axial load. This axial load accounts for 27% of the weight of the commercial vehicle itself and the wind resistance combined. To drive this 27% additional harmful derived axial load, the commercial vehicle must consume the same proportion of energy. This consumed energy is 100% converted into heat, resulting in serious heating of the existing commercial vehicle wheel hub bearings. In particular, the temperature rise of the inner ring and rollers is higher than that of the outer ring. The grease evaporates, oxidizes, ages, and solidifies severely, and the grease (oil) needs to be replaced within a short period of time. This so-called maintenance is costly and time-consuming, seriously affecting the life of the wheel hub bearing. In order to prevent the wheel hub bearing from "stuck" or even "stuck" due to heating, the bearing must have sufficient clearance, which seriously affects the life of the wheel hub bearing (see Figure 18 ) According to practical experience, if the axial clearance is 0.15mm, the wheel hub bearing life is only about 50% of that with zero clearance. Existing commercial vehicle wheel hub bearings generally have clearances exceeding 0.15mm (including the impact of the positioning tolerances of various components on clearance), which explains their extremely short lifespan. Furthermore, commercial vehicle wheel end assemblies are often designed outdated, with numerous parts, large size, complex structure and processes, and high manufacturing costs. This low-energy, long-life bearing can address these issues.

[0176] (1) Application of this low-energy consumption and long-life bearing in the steering axle wheel end assembly of commercial vehicles.

[0177] The application of this low energy consumption and long life bearing in the wheel end assembly of the steering axle of commercial vehicles is shown in Figure 19 Due to the needs of actual working conditions, the low energy consumption and long life bearings on the steering axle wheel end assembly of commercial vehicles are Figure 1 The low energy consumption and long life bearings of this company are different as follows:

[0178] The outer oil seal 2 is removed from the low-energy, long-life bearing and fabricated as a separate outer oil seal, which is placed on the outside of the outer rib 3. This seal can both seal the grease inside the bearing and transmit axial force. Alternatively, the outer rib 3 and the outer oil seal 2 can be optimized into a single component, which is more convenient to manufacture. The inner oil seal 8 of the bearing is also removed from the low-energy, long-life bearing and fabricated as a separate outer oil seal, which is placed on the inside of the wheel hub, sealing the grease inside the bearing and preventing it from leaking. The wheel rim and brake disc (or brake drum) are fastened to the wheel hub (or the hub flange) with screws.

[0179] Furthermore, the steering axle wheel end assembly of this commercial vehicle is upgraded (see Figure 20 ),exist Figure 19 On this basis, the outer ring of the low-energy consumption and long-life bearing and the wheel hub are integrated into a part 1408, and the rim (or rim adapter plate) and the brake disc (or brake drum) are fastened to the wheel hub (or the flange of the wheel hub) by screws.

[0180] (2) Application of this low-energy consumption and long-life bearing in the wheel end assembly of the commercial vehicle drive axle.

[0181] The application of this low energy consumption and long life bearing in the commercial vehicle drive axle wheel end assembly is shown in Figure 21 Due to the needs of actual working conditions, the low energy consumption and long life bearings on the wheel end assembly of the commercial vehicle drive axle are Figure 1 The low energy consumption and long life bearings of this company are different as follows:

[0182] In addition to the outer oil seal and outer flange Figure 21 In addition to the structure, you can also refer to the other structures in the previous section (1). The inner oil seal 8 of the bearing is removed from the low-energy consumption and long-life bearing and is made into a separate outer oil seal and placed inside the wheel hub to seal the grease inside the bearing and prevent it from leaking out. The rim and brake disc (or brake drum) are fastened to the wheel hub (or the flange of the wheel hub) by screws.

[0183] Furthermore, the commercial vehicle drive axle wheel end assembly is upgraded (see Figure 22 ),exist Figure 21On the basis of the low energy consumption and long life bearing, the outer ring and the wheel hub are integrated into a part 1506, and the rim and the brake disc (or brake drum) are fastened to the wheel hub (or the flange of the wheel hub) by screws.

[0184] Example 20:

[0185] The main structure of this embodiment is the same as that of embodiment 18. Furthermore, this low-energy consumption and long-life bearing is used in a passenger car wheel end assembly.

[0186] As we all know, existing passenger car wheel hub bearings generally use the first, second, and third generation hub units, most of which have double row angular contact ball bearing structures (see Figure 11 The contact angles between the two rows of steel balls and the inner and outer raceways are mostly 36°. This excessively large angle causes existing wheel hub bearings to bear significant additional, harmful derived axial loads. As shown in Table 2, this axial load accounts for 72% of the combined weight of the passenger vehicle and windage. To drive this 72% of additional, harmful derived axial load, the passenger vehicle necessarily consumes a similar amount of energy, 100% of which is converted into heat. This leads to significant heating in existing passenger vehicle wheel hub bearings, grease evaporation, oxidation, aging, and solidification, resulting in significant energy waste and a serious impact on the wheel hub bearing life. Furthermore, although third-generation wheel hub units are currently the highest-grade wheel hub bearings used in large-scale vehicle installations, they have numerous parts, poor moment rigidity, a bulky design, complex structure, and difficult processing and manufacturing processes, resulting in high costs. This low-energy, long-life bearing can address these issues.

[0187] Since the third generation wheel hub unit is the highest level wheel hub bearing installed in large quantities, this low energy consumption and long life bearing is also used as an example to illustrate the problem. The application of this low energy consumption and long life bearing in passenger car wheel end assembly is shown in Figure 2. Figure 23 Due to the needs of actual working conditions, the low energy consumption and long life bearings on the passenger wheel end assembly are Figure 1 The low energy consumption and long life bearings of this company are different as follows:

[0188] The inner and outer rings of the bearing are designed with flanges. Figure 23 In addition to the structure, you can also refer to the other structures in the previous section (1). The second-generation hub unit is just a flange designed on the outer ring of the low-energy consumption and long-life bearing, and its interior is still the structure of the low-energy consumption and long-life bearing. Therefore, the first, second and third generation hub units for passenger cars that use the innovative design of the low-energy consumption and long-life bearing are all protected by patents.

[0189] Furthermore, the passenger wheel end assembly is upgraded to the fourth generation hub unit (see Figure 24), based on the third generation hub unit, the universal joint cover 17 is mechanically connected to the inner ring of the low energy consumption and long life bearing, which saves the processing of internal and external splines and saves raw materials.

[0190] Example 21:

[0191] The main structure of this embodiment is the same as that of Example 18. Furthermore, this low-energy consumption and long-life bearing is used in rail transit vehicles.

[0192] Existing ordinary freight and passenger train wheel bearings, subway and high-speed rail EMU axle box bearings, mostly use double row tapered roller bearings (see Figure 13 ), and most of them are imported bearings, or foreign-funded domestically produced, which is a typical "bottleneck" project. The contact angle of the wheelset (axle box) bearings of existing rail transit vehicles is mostly 10°. This angle is designed to be too large, causing the existing wheelset (axle box) bearings to bear a large additional harmful derived axial load. As can be seen from Table 2, this axial load accounts for 18% of the combined weight of the rail transit vehicle itself and wind resistance. To drive this 18% additional harmful derived axial load, the rail transit vehicle must consume the same proportion of energy. This consumed energy is 100% converted into heat, resulting in serious heating of the existing rail transit wheelset (axle box) bearings, serious grease evaporation, oxidation, aging, and solidification, and serious energy waste, which seriously affects the life of the rail transit wheelset (axle box) bearings. In addition, the existing rail transit wheelset (axle box) bearings are large in size, complex in structure, difficult in process and manufacturing, and costly. This low-energy consumption and long-life bearing can solve the above problems.

[0193] This low energy consumption and long life bearing is used as a wheel set (axle box) bearing (see Figure 1 ) can be installed on rail vehicle axles. Through its innovative internal structural design, this low-energy, long-life bearing not only completely resolves the previously detailed issue of abnormal spalling of bearing components in rail transit wheelsets (axleboxes), but also significantly reduces the additional, harmful, derived axial load borne by existing wheelset (axlebox) bearings from 18% of their radial load to 2.4%. This translates to a corresponding reduction in heat and energy consumption. This innovation alone significantly reduces temperature rise, energy consumption, and grease evaporation, oxidation, curing, and aging. It also completely eliminates the "pumping effect" of grease that can easily occur with existing bearing structures. Furthermore, it completely resolves the "hot axle," "hot-cut axle," and "burning axle" issues that have plagued the rail transit industry both domestically and internationally for over 200 years. By optimizing the internal temperature distribution of the bearing, the temperature rise of each component is uniform, resulting in smoother heat transfer and more effective heat dissipation.

[0194] The detailed analysis is as follows (see Figure 1and 14 ): As we all know, in addition to the temperature rise, the temperature rise of each part of the existing rail transit wheelset (axle box) bearings is not the same. The existing bearings have a contact angle of 10°. In theory, there is sliding friction between the ball base surface of the roller and the large rib. The sliding friction coefficient is much higher than the rolling friction coefficient, resulting in the highest heat generation and temperature rise between the roller and the large rib. In addition, the roller and the inner and outer raceways generate almost the same friction temperature rise. Due to the large clearance, the roller only contacts the outer raceway once in a very narrow load-bearing area of ​​the outer ring for each rotation. The heat of the roller is difficult to transfer to the outer ring. Therefore, the temperature rise of the inner ring and roller of the existing bearing is greater than that of the outer ring. The actual operation of the bearing just verifies this. According to the above theory, the existing wheelset (axle box) bearings have an interference fit between the inner ring and the axle, and the heat of the inner ring is easily transferred to the axle, causing the temperature of the axle to rise along with the inner ring. On the contrary, since the outer ring is either tightly fitted with the axle box or most of the outer circle is exposed to the air, and the area of ​​the outer ring is about twice that of the inner ring, the heat generated by the outer ring can be easily dissipated into the air directly or through the axle box. As time accumulates, when the temperature of the inner ring and the axle rises to a certain level, "hot axle", "burning axle" and "hot-cut axle" accidents occur. Because the outer rib 3 and outer ring 5 of this low-energy, long-life bearing are either integrated or constructed as two separate parts, the inner ring, lacking a rib, generates less heat than the outer ring. This significantly reduces the amount of harmful heat generated in the entire bearing from 18% to 2.4%. Because the outer ring has a larger heat dissipation area than the inner ring, even if the heat generated by the outer ring and outer rib exceeds that of the inner ring, the heat can easily be dissipated directly or through the axle box to the air because the outer ring is either tightly fitted with the axle box or most of its outer circumference is exposed to the air. Furthermore, because all rollers are in constant contact with the inner and outer raceways and the outer rib with zero clearance, heat from all bearing components is easily dissipated to the air through the outer ring.

[0195] Example 22:

[0196] The main structure of this embodiment is the same as that of Example 18. Furthermore, this low-energy consumption and long-life bearing is used in the transmission mechanism of the rail transit gearbox.

[0197] Many transmission mechanisms, especially gear transmissions, require roller bearings to support the load when transmitting high-speed, heavy-load transmissions. Because helical gears offer numerous advantages over spur gears when transmitting high-speed, heavy-load transmissions, existing high-speed, heavy-load gear transmissions employ either tapered roller bearings or a combination of cylindrical roller bearings and thrust ball bearings. Regardless of the configuration, the high-speed, heavy-load transmissions generate relatively high heat in the bearings, requiring clearance, as in the various existing bearings discussed above. This clearance significantly shortens bearing life and increases noise, temperature, and vibration. The existing rail transit gearbox bearings in this embodiment are all imported, representing a typical bottleneck. China boasts the largest number of subway and high-speed trainsets worldwide, with each eight-car standard subway or high-speed train requiring 16 gearboxes. Therefore, using subway and high-speed trainset gearboxes as an example to illustrate the widespread commonality of these issues is of significant practical significance.

[0198] The existing main high-speed EMU gearboxes all use a single-stage helical gear transmission (see Figure 25 ), this transmission structure is simple, requires fewer shafts, requires fewer bearings, and has high transmission efficiency. It is most commonly used on high-speed EMUs. The input shaft 21 generally uses a four-point contact ball bearing 20 plus two cylindrical roller bearings 18. The four-point contact ball bearing 20 bears the axial load of the entire input shaft 21, while all radial loads on the input shaft are borne by the two cylindrical bearings. Therefore, in the design of the bearing seat, the bearing seat and the outer ring of the four-point contact ball bearing adopt a clearance fit; the bearing seat and the two cylindrical bearings adopt a transition fit. This arrangement is safer and more reliable than using two tapered bearings on the input shaft. Because the input shaft rotates at a high speed, the tapered bearing needs to bear both radial and axial loads during operation. The rolling elements are in rolling contact with the inner ring raceway and sliding contact with the ribs at the same time, generating higher heat, which places higher demands on the tapered bearings. Therefore, the current high-speed EMU gearbox input shaft bearing arrangement mainly adopts a four-point contact ball bearing plus two cylindrical bearings.

[0199] The output shaft of the gearbox has a much lower speed than the input shaft and has to bear a large axial load. Therefore, the bearings are generally paired with tapered bearings. The existing tapered bearings can withstand high axial forces but also generate a lot of heat. After the tapered bearings are installed, the axial clearance needs to be adjusted to adapt to the clearance reduction caused by the operating temperature rise. Due to the high speed and heavy load, the radial clearance of the cylindrical roller bearings of the input shaft is 0.065-0.1mm, and the radial clearance of the tapered roller bearings of the output shaft is 0.16-0.22mm. Such a large clearance seriously affects the life of the bearings (see Figure 18 ), while the noise, vibration and temperature rise of the entire gearbox also increase.

[0200] The use of this low energy consumption and long life bearing can solve the above problems (see Figure 26 ). First, because the clearance of these low-energy, long-life bearings is zero, the life of the gearbox bearings is greatly extended, as is the mileage between "scheduled repairs" for the gearbox. At the same time, the noise, vibration, and temperature rise are significantly reduced. Because the input shaft uses two low-energy, long-life bearings with a contact angle below 3°, these two bearings, like existing cylindrical roller bearings, can withstand both high speeds and large radial loads, as well as small axial loads, reducing the number of existing three bearings to two. Because the output shaft uses two low-energy, long-life bearings with a contact angle designed based on the ratio of radial to axial loads borne by the large gear, these two bearings, like existing tapered roller bearings, can withstand both large axial loads and large radial loads. Furthermore, the optimized contact angle achieves optimal transmission efficiency.

[0201] Example 23:

[0202] The main structure of this embodiment is the same as any one of the embodiments 1 to 22. Furthermore, the low energy consumption and long life bearing is in the optimal working state of zero clearance when working, which means that the clearance between the spherical base surface 701 of the roller 7 and the end surface of the step portion 302 of the outer rib 3, and between the conical surface of the roller 7 and the inner raceway 101 of the inner ring 1 and the outer raceway 501 of the outer ring 5 is always zero (see Figure 8 ).

[0203] The axial clearance T value between the small end face 702 of the roller 7 and the working face 601 of the small rib 6 of the low energy consumption and long life bearing is (see Figure 14 ) size has nothing to do with the load and life of the bearing. Only when the vehicle makes a sharp turn, the centrifugal force generated causes axial relative movement between the inner ring 1, the outer ring 5 and the outer rib 3. The spherical base surface 701 and the small end surface 702 of the roller 7 simultaneously contact the step 302 of the outer rib 3 and the working surface 601 of the small rib 6, respectively, to transmit the axial force to the inner ring 1 or the outer ring 5 and the outer rib 3. After turning the corner, the centrifugal force or axial force disappears, the bearing only bears pure radial load, and the bearing returns to the optimal working state of 0 clearance.

[0204] The size of the axial clearance T between the small end face 702 of the roller 7 and the working surface 601 of the small rib 6 is only related to the temperature rise of the bearing parts. Since the temperature rise of the low-energy consumption and long-life bearing is greatly reduced compared with the existing bearings, and the heat generation of each part is almost the same, although the inner and outer rings have a certain amount of expansion, in most cases, only one of the inner or outer ring is axially positioned and clamped, and the axial freedom of the other is limited by the former, such as commercial vehicle wheel hub bearings (see Figures 19-24), their common feature is that the inner ring 1 is axially positioned and clamped. When the inner ring 1, outer ring 5, roller 7 and outer rib 3 expand due to heat, the elongation in the longitudinal direction due to thermal expansion is almost equal, so the axial clearance T value between the small end face 702 of the roller 7 and the working surface 601 of the small rib 6 is almost unaffected. A major feature of the internal structural design of this low-energy consumption and long-life bearing is that the inner ring 1, outer ring 5 and roller 7 heat up uniformly. As a result, the expansion of the inner and outer rings and rollers is almost equal, both radially and axially. Even if the combined radial expansion of the inner ring 1 and roller 7 is greater than that of the outer ring 5, the outer ring 5 and outer rib 3 will drive the roller 7 toward the small end 102 of the inner ring 1, slightly reducing the T value mentioned above. In addition, because the outer ring and the hub and axle box are fitted with a transition or small clearance, if the outer ring expands slightly due to temperature rise, it only reduces the clearance between the outer ring, the hub and axle box, and the bearing still operates normally.

Claims

1. A low energy consumption and long life bearing, characterized by: It comprises an inner ring (1), an outer rib (3), a retainer (4), an outer ring (5), a small rib (6) and a plurality of tapered rollers (7); The inner ring (1) is a structure with a cone shape in the middle, a cylindrical shape at both ends, and a cylindrical hole inside. The end with a smaller radius of the cylindrical segments at both ends is marked as a small end (102), and the end with a larger radius is marked as a large end (103). The area between the large end (103) and the small end (102) is marked as an inner raceway (101); The small rib (6) is a hollow cylindrical structure, which is mounted on the outer cylindrical surface of the inner ring small head end (102), and a working surface (601) is provided on the end surface of the small rib (6) facing the large head end (103); The outer ring (5) is a hollow rotating body structure; the inner hole of the outer ring (5) includes an outer raceway (501) section and a cylindrical section (502); the inner hole of the outer raceway (501) section is in a conical shape, and the end with a smaller radius of the outer raceway (501) section is recorded as a small diameter end, and the end with a larger radius is recorded as a large diameter end, and the small diameter end is connected to the cylindrical section (502); The outer rib (3) is an annular structure as a whole, comprising an outer rib body (301) and a step portion (302); one end of the outer rib body (301) is connected or communicated with the large diameter end of the outer raceway (501), and an annular step portion (302) is provided on the inner side wall at the intersection position; When the inner ring (1) and the outer ring (5) are assembled, the inner ring (1) is located in the inner hole of the outer ring (5), and the inner raceway (101), the outer raceway (501) and the step portion (302) form a friction working area; A retainer (4) is installed in the friction working area; The plurality of tapered rollers (7) are located in the friction working area and are evenly separated by the retainer (4) window; in the working state, the tapered rollers (7) rotate in the friction working area along the inner raceway (101), the outer raceway (501) and the step portion (302) of the outer rib.

2. The low energy consumption and long life bearing according to claim 1, characterized in that: The outer diameter of the inner raceway (101) section gradually increases from the small end (102) to the large end (103).

3. The low energy consumption and long life bearing according to claim 1, characterized in that: The semi-cone angle of the outer raceway (501) is a=1° to 9°.

4. The low energy consumption and long life bearing according to claim 1, characterized in that: The tapered roller (7) is a cone-shaped structure, and the tapered surface of the tapered roller (7) is in contact with the inner raceway (101) and the outer raceway (501) with zero clearance.

5. The low energy consumption and long life bearing according to claim 1, characterized in that: The tapered roller (7) is a cone-shaped structure, and the end with a larger radius is marked as a spherical base surface (701), and the spherical base surface (701) is in contact with the step portion (302).

6. The low energy consumption and long life bearing according to claim 1, characterized in that: The inner ring (1) and the small rib (6) are an integrally formed structure.

7. The low energy consumption and long life bearing according to claim 1, characterized in that: The small rib (6) and the inner ring (1) are two parts; A plurality of screw holes are provided on the outer cylindrical surface of the small rib (6). When the small rib (6) is assembled, cylindrical pins are placed in the screw holes with an interference fit or an overfit with the screw holes. The small rib (6) is axially positioned and locked on the inner ring (1) by means of a set screw and a thread on one end of the cylindrical pin away from the set screw.

8. The low energy consumption and long life bearing according to claim 1, characterized in that: The outer ring (5) and the outer rib (3) are two parts or an integrally formed structure.

9. The low energy consumption and long life bearing according to claim 1, characterized in that: The bearing further comprises an outer oil seal (2) and an inner oil seal (8); The outer oil seal (2) is arranged between the inner ring big end (103) and the outer rib (3), and is interference fit with the inner hole of the outer rib body (301), and is interference sealing fit with the outer cylindrical surface of the inner ring big end (103); The inner oil seal (8) is arranged between the small rib (6) and the outer cylindrical section (502), and is interference-fitted with the inner hole of the outer cylindrical section (502) and interference-sealed with the outer cylindrical surface of the small rib (6).

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