A large-opening axle box

Abstract

The present application relates to railway freight car technical field, aims at solving the problem that the prior art cannot meet the new generation four array THDS full light spot straight detection, the sample of temperature sampling is few, the detection precision is insufficient, it is difficult to truly reflect bearing heat distribution, and the reliability of axle temperature early warning is poor, and provides a large opening axle box, including arc saddle surface, tangent straight line segment and eight-shaped straight line segment; The tangent straight line segment is tangent to the lower end of the arc saddle surface, the eight-shaped straight line segment is connected to the lower end of the tangent straight line segment and extends downward and outward, and the lower end of the eight-shaped straight line segment is transitionally connected with the spring support platform of the axle box; The lower part of the axle box forms a large opening detection opening, and the detection beam of the infrared axle temperature detection system directly detects the surface of the bearing outer ring in the large opening detection opening in the form of full light spot. The beneficial effects of the present application are to realize two array and four array THDS full light spot straight detection, eliminate detection error, increase sampling quantity, improve the reliability of axle temperature early warning, and ensure the bearing strength of the axle box.

Description

Technical Field

[0001] This invention relates to the field of railway freight car technology, and more specifically, to a large-opening axle box. Background Technology

[0002] Currently, railway bogies worldwide are mainly divided into two structural types: cast steel three-piece type and welded frame type. The axle box system of the cast steel three-piece type bogie generally consists of rolling bearing assembly, bearing saddle, and rubber pad. It has a simple structure, strong adaptability, and good maintenance process. In this axle box system, the outer ring of the bearing directly mates with the bearing saddle surface to achieve load transfer. There is no separate axle box body, and the transverse geometric cross-section of the bearing saddle surface is nearly semi-circular. Nearly half of the lower part of the bearing body is exposed, which can meet the full-spot direct detection requirements of the existing railway freight car infrared axle temperature detection system (THDS). The axle box system of the welded frame type bogie generally consists of rolling bearing assembly, axle box body, spring assembly, and vibration damping device. Its structure is more complex and the maintenance process is relatively low. The existing axle box body and bearing mating type is mostly a full circular structure or a near-full circular structure, that is, the transverse geometric cross-section of the axle box is a closed structure, or only a detection process hole of limited size is set in the lower part of the axle box body.

[0003] The existing circular axle box uses a closed circular saddle surface to fit the bearing outer ring, which cannot directly detect the bearing body temperature. The actual bearing temperature can only be estimated by indirectly detecting the axle box temperature. Due to factors such as the axle box structure distribution and manufacturing defects, the detection data has a large temperature difference error and low detection accuracy. The solution of configuring axle end temperature monitoring device is only suitable for electrified vehicles and cannot be adapted to the current railway freight cars in the de-energized state. Although the existing near-circular axle box has detection process holes in the lower part of the saddle surface, the size of the process holes is generally small due to the structural limitations of adjacent components. The number of temperature samples that can be collected is very limited and cannot meet the full-spot direct detection requirements of the new generation four-array THDS. It is difficult to comprehensively and accurately reflect the thermal distribution of the bearing body, resulting in insufficient timeliness and accuracy of axle temperature warning, which is not conducive to ensuring the operational safety of railway freight cars. Summary of the Invention

[0004] The present invention aims to provide a large-aperture axle box to solve the problems in the existing technology that cannot meet the requirements of the new generation of four-array THDS full-spot direct detection, the small number of temperature sampling samples, the insufficient detection accuracy, the difficulty in truly reflecting the bearing heat distribution, and the poor reliability of shaft temperature early warning.

[0005] This invention is implemented as follows: This invention provides a large-opening axle box body, which is applied to welded frame bogies for railway freight cars. The transverse geometric cross-section of the axle box body has a composite curve structure, including a circular arc saddle surface, a tangent straight line segment, and a figure-eight straight line segment connected in sequence. The aforementioned arc-shaped saddle surface is used to mate with the outer ring of the bearing to transmit vertical loads. The aforementioned tangential straight line segment is tangentially connected to the lower end of the aforementioned arc-shaped saddle surface. The aforementioned figure-eight straight line segment is connected to the lower end of the aforementioned tangential straight line segment and extends downward and outward. The lower end of the aforementioned figure-eight straight line segment is transitionally connected to the spring support of the axle box body. The lower part of the aforementioned axle box body forms a large-aperture detection opening, and the detection beam of the infrared shaft temperature detection system probes the outer ring surface of the bearing inside the large-aperture detection opening in the form of a full-spot light.

[0006] Preferably, the angle between the aforementioned figure-eight straight segment and the central axis of the axle box section is 45°, and the aforementioned angle is compatible with the detection elevation angle and horizontal angle parameters of the infrared axle temperature detection system.

[0007] Preferably, the maximum longitudinal dimension of the aforementioned large-aperture detection opening is 530mm, which satisfies the requirement that the longitudinal displacement of the infrared axial temperature detection system's full-spot direct detection reaches 160mm.

[0008] Preferably, the maximum lateral dimension of the aforementioned large-aperture detection opening is 320mm, covering the full spot detection range of the infrared axle temperature detection system under the condition of maximum lateral displacement of the wheelset.

[0009] Preferably, the spring bearing platform of the aforementioned axle box is provided with a bearing surface, and the bearing surface is arranged parallel to the aforementioned figure-eight straight segment.

[0010] Preferably, the axle box body extends longitudinally along the vehicle and is laterally offset to form an axle box skirt, and the cross-section of the axle box skirt has an inverted "L" shape.

[0011] Preferably, the middle part of the axle box skirt is provided with discontinuous V-shaped reinforcing ribs.

[0012] Preferably, the lower part of the primary spring support of the aforementioned axle box body is provided with a semi-closed grid-shaped anti-crushing structure.

[0013] Preferably, the infrared axial temperature detection system includes a two-array THDS and a four-array THDS, and the large-aperture detection opening simultaneously satisfies the full-spot direct detection of both the two-array THDS and the four-array THDS.

[0014] Preferably, a transition arc is provided at the junction of the arc-shaped saddle surface and the tangent line segment, and at the junction of the tangent line segment and the figure-eight line segment.

[0015] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are: 1. The accuracy of shaft temperature detection has been significantly improved.

[0016] This invention employs a composite curved cross-section consisting of a circular arc saddle surface, a tangent straight line segment, and a figure-eight straight line segment connected in sequence. This creates a large-aperture detection opening at the bottom of the axle box, allowing the infrared axle temperature detection system to directly irradiate the outer ring surface of the bearing with a full-spot light. This replaces the indirect detection method using a traditional circular axle box, completely eliminating temperature conduction errors caused by differences in axle box structure and manufacturing deviations, thus fundamentally improving the accuracy of axle temperature detection data.

[0017] 2. The integrity of the sampling data has been greatly enhanced.

[0018] The large-aperture detection opening achieves maximum size design in both the longitudinal and transverse directions, effectively extending the effective detection time when a vehicle passes through the THDS detection point. The number of effective temperature samples per unit time is significantly increased compared to traditional structures, enabling more comprehensive and continuous collection of heat distribution data on the bearing surface. This accurately reflects the bearing's operating temperature state, providing sufficient and reliable data support for early warning of axle temperature faults, effectively improving the timeliness and accuracy of axle temperature warnings, and ensuring the operational safety of railway freight cars.

[0019] 3. The structural load-bearing capacity is stable and reliable.

[0020] By arranging the bearing surface of the spring bearing platform parallel to the figure-eight straight segment and setting smooth transition arcs at the joints of each structural segment, a smooth and uniform vertical load transfer path is ensured, avoiding stress concentration caused by abrupt changes in cross-section. The axle box skirt structure with an inverted "L" shaped cross-section effectively compensates for the weakening of vertical bending stiffness caused by the large opening design. The semi-closed grid-shaped anti-crushing structure set at the bottom of the spring bearing platform further enhances the local compressive bearing capacity of the bearing platform. The multiple structural reinforcement designs jointly ensure the overall structural strength, deformation resistance, and fatigue durability of the axle box, enabling it to meet the load-bearing requirements of the vehicle under all working conditions and throughout its entire life cycle, even with a large opening layout.

[0021] 4. It has strong versatility and adaptability, and outstanding engineering value.

[0022] The overall structural design fully considers multiple constraints such as the vehicle's lower clearance, the maximum lateral displacement of the wheelset, and the assembly space of adjacent components. It can be adapted and installed without modifying the existing welded frame bogie's primary suspension overall structure. It is also compatible with two-array and four-array THDS detection equipment. Its application scope covers multiple types of railway freight car bogies, and it has a good foundation for engineering promotion and application value. Attached Figure Description

[0023] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0024] Figure 1 This is a transverse cross-sectional view of a large-aperture axle box body according to an embodiment of the present invention; Figure 2 This is a front view of the positional relationship between the shaft box and the two-array THDS detector in an embodiment of the present invention; Figure 3 This is a side view showing the positional relationship between the shaft housing and the two-array THDS detector in an embodiment of the present invention; Figure 4 This is a top view showing the positional relationship between the shaft box and the two-array THDS detector in an embodiment of the present invention; Figure 5 This is a front view of the positional relationship between the shaft housing and the four-array THDS detector in an embodiment of the present invention; Figure 6 This is a side view showing the positional relationship between the shaft housing and the four-array THDS detector in an embodiment of the present invention; Figure 7 This is a top view showing the positional relationship between the shaft box and the four-array THDS detector in an embodiment of the present invention; Figure 8 This is a front view of the axle box skirt in an embodiment of the present invention; Figure 9 This is an embodiment of the present invention. Figure 8 Sectional view at point AA; Figure 10 This is a bottom view of a large-aperture axle box body according to an embodiment of the present invention.

[0025] Icons: 1-Axle box body, 2-Circular arc saddle surface, 3-Tangent segment, 4-Figure-eight straight segment, 5-Large opening detection opening, 6-Infrared axle temperature detection system, 7-Bearing surface, 8-Axle box skirt, 9-Reinforcing rib, 10-Anti-crushing structure, 11-Dual array THDS, 12-Four array THDS, 13-First inner detection beam, 14-First outer detection beam, 15-Second inner detection beam, 16-Middle detection beam I, 17-Middle detection beam II, 18-Second outer detection beam. Detailed Implementation

[0026] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0027] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0028] Example See Figures 1-10 This embodiment proposes a large-opening axle box body, which is applied to the welded frame bogie of railway freight cars. The transverse geometric cross-section of the axle box body 1 is a composite curve structure, including a circular arc saddle surface 2, a tangent straight line segment 3 and a figure-eight straight line segment 4 connected in sequence. The arc-shaped saddle surface 2 is used to mate with the outer ring of the bearing to transmit vertical loads. The tangent straight section 3 is tangentially connected to the lower end of the arc-shaped saddle surface 2. The figure-eight straight section 4 is connected to the lower end of the tangent straight section 3 and extends downward and outward. The lower end of the figure-eight straight section 4 is transitionally connected to the spring support of the axle box 1. A large-aperture detection opening 5 is formed at the lower part of the axle box 1, and the detection beam of the infrared shaft temperature detection system 6 directly probes the outer ring surface of the bearing inside the large-aperture detection opening 5 in the form of a full-spot light.

[0029] During operation, the arc-shaped saddle surface 2 cooperates with the outer ring of the bearing to transmit the vertical load. The load is transmitted to the spring support through the tangential straight section 3 and the figure-eight straight section 4. The detection beam of the infrared shaft temperature detection system 6 directly probes the surface of the outer ring of the bearing in the form of a full spot through the large-opening detection opening 5, realizing the direct acquisition of the bearing temperature.

[0030] The large-opening axle box disclosed in this embodiment adopts a composite curved transverse geometric section composed of a circular arc saddle surface 2, a tangent straight line segment 3, and a figure-eight straight line segment 4 connected in sequence. Under the premise of ensuring stable transmission of the vertical load of the bearing outer ring and achieving a smooth transition connection with the spring support, a large-opening detection opening 5 is formed at the lower part of the axle box 1. This allows the detection beam of the infrared shaft temperature detection system 6 to directly probe the surface of the bearing outer ring in the form of a full spot, thereby achieving direct and accurate acquisition of the bearing temperature.

[0031] See Figures 1-10In this embodiment, the angle between the figure-eight straight segment 4 and the central axis of the cross section of the axle box 1 is 45°, which is compatible with the detection elevation angle and horizontal angle parameters of the infrared axle temperature detection system 6.

[0032] Specifically, the design of the figure-eight straight segment 4 with a 45° included angle can accurately match the detection elevation angle and horizontal angle parameters of the infrared shaft temperature detection system 6, ensuring that the detection beam can directly hit the outer ring surface of the bearing in the form of a full spot without obstruction, avoiding the side wall of the shaft housing 1 from blocking the light path. While ensuring the transition connection strength between the shaft housing 1 and the spring support, it maximizes the effective detection range of the lower detection opening and improves the accuracy and reliability of shaft temperature detection.

[0033] See Figures 1-10 In this embodiment, the maximum longitudinal dimension of the large-aperture detection opening 5 is 530mm, which satisfies the requirement that the longitudinal displacement of the infrared shaft temperature detection system 6, which has a full-spot direct detection capability, reaches 160mm.

[0034] Specifically, the design of setting the maximum longitudinal size of the detection opening to 530mm, which can cover a longitudinal displacement of 160mm, effectively extends the effective duration of the full-spot direct detection when the vehicle passes through the 6 detection points of the infrared axle temperature detection system. This significantly increases the number of effective temperature samples per unit time, allowing for more comprehensive and continuous collection of thermal distribution data of the bearing body. It also accurately reflects the actual operating temperature state of the bearing, effectively improving the timeliness and accuracy of axle temperature fault early warning and ensuring the safe operation of railway freight cars.

[0035] See Figures 1-10 In this embodiment, the maximum lateral dimension of the large-aperture detection opening 5 is 320mm, covering the full spot detection range of the infrared axle temperature detection system 6 under the condition of maximum lateral displacement of the wheelset.

[0036] Specifically, the maximum lateral size of the detection opening is set to 320mm, which can fully cover the maximum lateral displacement of the wheelset caused by factors such as wheel-rail lateral clearance, wheel flange wear, and track lateral tolerance. This ensures that the full spot of the infrared axle temperature detection system 6 can directly hit the outer surface of the bearing without obstruction under any lateral displacement of the wheelset, avoiding the problems of detection spot truncation and sampling data loss caused by lateral displacement of the wheelset. This ensures the effectiveness and data integrity of axle temperature detection under all vehicle operating conditions and improves the stability and reliability of axle temperature warning.

[0037] See Figures 1-10 In this embodiment, a bearing surface 7 is provided on the spring bearing platform of the axle box 1. The bearing surface 7 and the figure-eight straight line segment 4 are arranged parallel to each other to achieve coordinated structural deformation and smooth load transmission.

[0038] Specifically, by setting the bearing surface 7 of the spring bearing platform and the figure-eight straight segment 4 as parallel structures, the vertical load transmitted by the primary suspension can be evenly and smoothly transmitted along the parallel wall to the mating area of ​​the saddle surface and the bearing, avoiding stress concentration problems caused by abrupt changes in cross section and structural incoordination, achieving coordinated and unified structural deformation, and effectively improving the overall bearing capacity and fatigue reliability of the axle box 1 on the basis of the structure of the large-opening detection opening 5, ensuring the structural safety of the bogie during long-term operation.

[0039] See Figures 1-10 In this embodiment, the axle box body 1 extends longitudinally along the vehicle and is laterally offset to form an axle box skirt 8. The cross-section of the axle box skirt 8 has an inverted "L" shape structure, which is used to compensate for the weakening of vertical bending stiffness caused by the large opening structure.

[0040] Specifically, the axle box skirt 8 structure with an inverted "L" shaped cross-section is adopted. Under the multiple dimensional constraints of the vehicle's lower limit, lateral outer limit, and inner wheel structure, it can effectively compensate for the weakening of the vertical bending stiffness of the axle box 1 caused by the design of the large-opening detection opening 5. This significantly improves the bending load-bearing capacity and structural stability of the skirt part, avoids excessive structural deformation or fatigue damage caused by the large-opening layout, and ensures that the overall mechanical performance of the axle box 1 meets the requirements for long-term use while ensuring the full-spot direct detection space requirements of the infrared axle temperature detection system 6.

[0041] See Figures 1-10 In this embodiment, the middle part of the axle box skirt 8 is provided with discontinuous V-shaped reinforcing ribs 9.

[0042] Specifically, discontinuous V-shaped reinforcing ribs 9 are set in the middle of the axle box skirt 8, which can effectively strengthen the structural stiffness of the skirt part along the load transmission direction, further offsetting the weakening of vertical bending performance caused by the design of the large-opening detection opening 5, and improving the structural deformation resistance and fatigue life. At the same time, the discontinuous arrangement can avoid blocking the detection beam of the infrared axle temperature detection system 6. Under the premise of ensuring that the effective range of the full beam direct detection is not interfered with, the mechanical performance of the axle box body 1 is improved with a lower increase in structural weight, taking into account both the detection function requirements and structural reliability.

[0043] See Figures 1-10 In this embodiment, a semi-closed grid-shaped anti-crushing structure 10 is provided at the lower part of the primary spring support of the axle box 1 to improve the compressive bearing capacity of the spring support.

[0044] Specifically, a semi-closed grid-shaped anti-crushing structure 10 is set at the lower part of the primary spring bearing platform, which can effectively enhance the local compressive stiffness and load-bearing capacity of the bearing platform, evenly distribute the vertical load transmitted by the primary spring, avoid local crushing deformation and stress concentration problems of the bearing platform under heavy load and impact conditions, significantly improve the structural reliability and fatigue life of the axle box 1, and the semi-closed structure form has both good forming processability and lightweight effect, which is compatible with the overall structural layout of the large-opening axle box 1.

[0045] See Figures 1-10 In this embodiment, the infrared axial temperature detection system 6 includes a two-array THDS11 and a four-array THDS12, and the large-aperture detection opening 5 simultaneously meets the full-spot direct detection requirements of both the two-array THDS11 and the four-array THDS12.

[0046] Specifically, the large-aperture detection opening 5 can simultaneously adapt to the full-spot direct detection requirements of both two-array and four-array infrared shaft temperature detection systems 6, without requiring structural modifications to the shaft housing 1 for different detection methods, significantly improving the versatility and adaptability of the shaft housing 1; at the same time, it can realize direct detection of bearing body temperature, completely eliminating temperature difference errors caused by indirect measurement, and with the multi-dimensional detection of the four-array multi-beam system, it can more comprehensively collect bearing surface heat distribution data, effectively improving the timeliness and accuracy of shaft temperature fault early warning, and ensuring the safe operation of railway freight cars.

[0047] See Figures 1-10 In this embodiment, transition arcs (not shown in the figure) are provided at the junction of the arc-shaped saddle surface 2 and the tangent straight line segment 3, and at the junction of the tangent straight line segment 3 and the figure-eight straight line segment 4, in order to achieve a smooth connection.

[0048] Specifically, transition arcs are set at the junctions of the arc-shaped saddle surface 2 and the tangent straight line segment 3, and the junction of the tangent straight line segment 3 and the figure-eight straight line segment 4 to achieve smooth connection. This can effectively eliminate stress concentration caused by abrupt changes in the structural cross-section, avoid stress peaks at the junctions during load transfer, significantly improve the fatigue strength and structural durability of the axle box 1, optimize the load transmission path, ensure the stability of the mechanical properties of the large-aperture cross-section structure, and also help improve the casting processability of the axle box 1 and reduce the risk of forming defects.

[0049] See Figures 1-10In this embodiment, the figure-eight straight segment 4 is a symmetrical figure-eight structure, symmetrically distributed on both sides of the axle box 1 in the transverse direction, with its lower end transitionally connected to the spring bearing on the corresponding side. This symmetrical figure-eight arrangement ensures that the stress state on both sides of the axle box 1 is balanced and consistent, guaranteeing that the vertical load is uniformly transmitted to the spring bearing along both side walls, avoiding uneven structural stress caused by eccentric loading. Simultaneously, the symmetrical sidewall layout allows for symmetrical detection spaces on both sides of the lower axle box 1, accommodating the symmetrically arranged infrared axle temperature detection optical paths on both sides of the bogie, ensuring consistent axle temperature detection conditions for the bearings on both sides.

[0050] See Figures 1-10 In this embodiment, the large-aperture detection opening 5 has an overall axisymmetric and centrosymmetric structure, and the opening profile is adapted to the full-spot detection range of the infrared axle temperature detection system 6. The axisymmetric and centrosymmetric opening profile design allows the detection opening to completely cover the projection range of the detection beam under all working conditions, including lateral displacement of the wheelset and longitudinal passage of the vehicle through the detection point, avoiding the light spot being truncated by the opening edge and causing sampling data failure; at the same time, the opening profile is precisely matched with the full-spot detection range, controlling the opening size as much as possible while meeting the detection requirements, and reducing the impact on the overall structural strength of the axle box 1.

[0051] See Figures 1-10 In this embodiment, the axle box skirt 8 is offset outward in the lateral direction of the vehicle by 160mm. The lateral offset dimension of 160mm is the optimal value determined by combining the constraints of the vehicle's lower limit, the maximum lateral displacement of the wheelset, and the horizontal angle of the THDS detection. This value provides sufficient lateral space for the large-aperture detection opening 5, ensuring that the lateral detection range of the entire light spot is unobstructed, without exceeding the vehicle's limit requirements. At the same time, it matches the maximum lateral dimension of the detection opening, providing space for the arrangement of the stiffness reinforcement structure of the inverted "L" shaped section.

[0052] See Figures 1-10 In this embodiment, the arc-shaped saddle surface 2, the tangent line segment 3, and the figure-eight straight line segment 4 together form an open cross-sectional structure that is narrow at the top and wide at the bottom. The arc-shaped saddle surface 2 has an arc angle of less than 180°, and the lower surface of the bearing outer ring is exposed to the detection side through a large-aperture detection opening 5. The open cross-section, which is narrow at the top and wide at the bottom, breaks the closed structure of the traditional full-circle or near-full-circle shaft housing 1. Through the arc angle design of less than 180°, the lower half of the bearing outer ring is fully exposed while ensuring the effective bearing contact area between the saddle surface and the bearing outer ring. This provides the infrared shaft temperature detection system 6 with space to directly probe the bearing body from the cross-sectional structure, thus realizing the direct detection of the bearing temperature.

[0053] See Figures 1-10In this embodiment, the dual-array THDS11 includes a first inner probe beam 13 and a first outer probe beam 14, and the quad-array THDS12 includes a second inner probe beam 15, a middle probe beam I 16, a middle probe beam II 17, and a second outer probe beam 18. The large-aperture detection opening 5 can cover the entire beam path of all probe beams. The large-aperture detection opening 5 has sufficient dimensional margin in both longitudinal and transverse dimensions, and can simultaneously cover the two probe beams of the dual-array THDS11 and the four probe beams of the quad-array THDS12. This allows the same shaft housing 1 structure to be compatible with both existing dual-array and new-generation quad-array shaft temperature detection devices, without requiring modification of the shaft housing structure for different detection standards, greatly improving the product's versatility and adaptability.

[0054] See Figures 1-10 In this embodiment, the axle box 1 undergoes a heat treatment, and a galvanized anti-corrosion layer is provided on its outer surface. The heat treatment can effectively improve the comprehensive mechanical properties of the base material of the axle box 1, giving the structure both high strength and toughness, and better bearing the alternating loads and impact loads during bogie operation; the galvanized anti-corrosion layer on the outer surface can isolate external rainwater, dust and corrosive media, significantly improving the corrosion resistance of the axle box 1 in the complex outdoor operating environment of railways, extending the product's life cycle and reducing maintenance costs.

[0055] See Figures 1-10 In this embodiment, the grid-shaped anti-crushing structure 10 is a semi-closed structure with an open bottom, located directly below the bearing surface 7 of the primary spring support. Positioning the anti-crushing structure 10 directly below the spring bearing surface 7 allows it to directly receive and distribute the concentrated vertical load transmitted by the primary springs. The grid-shaped multi-grid rib structure evenly distributes the load to the surrounding substrate, effectively improving the local compressive strength of the support and preventing localized crushing deformation under heavy impact. The semi-closed design with an open bottom facilitates demolding during casting, simplifying the manufacturing process, and also controls the structural weight while ensuring reinforcement, achieving a lightweight design.

[0056] See Figures 1-10 In this embodiment, the large-opening axle box 1 is designed for welded frame bogies of railway freight cars. The core objective is to meet the full-spot direct detection requirements of the two-array and four-array infrared axle temperature detection system 6 (THDS). At the same time, it takes into account the bogie primary suspension assembly requirements, vehicle clearance constraints and the strength requirements of the axle box 1 itself. By combining cross-sectional structure optimization, detection opening extreme value design and load-bearing structure reinforcement, the bearing temperature can be directly and accurately detected while ensuring structural reliability.

[0057] In terms of overall structural layout, the transverse geometric section of the axle box 1 adopts a composite curve design, which is composed of a circular arc saddle surface 2, a tangent straight line segment 3, and a figure-eight straight line segment 4 connected in sequence. Among them, the circular arc saddle surface 2 cooperates with the outer ring of the bearing to transmit the vertical load, the tangent straight line segment 3 is tangentially transitioned to the lower end of the saddle surface, and the figure-eight straight line segment 4 extends downward and outward and is smoothly connected to the spring support. The angle between the figure-eight straight line segment 4 and the cross-sectional axis is set to 45°, which is compatible with the detection elevation angle and horizontal angle parameters of THDS. From the cross-sectional shape, sufficient optical path space is reserved for full-spot direct detection.

[0058] For the lower detection opening, the design maximizes both longitudinal and lateral dimensions. The longitudinal dimension is determined by considering the primary axle box suspension arrangement, the friction pairs and wear plates of the vibration damping device, and the assembly requirements of adjacent components such as the steel spring assembly, reaching a maximum of 530mm, which can cover a longitudinal detection displacement of 160mm. The lateral dimension comprehensively considers the maximum lateral displacement of the wheelset caused by factors such as wheel-rail lateral clearance, wheelset inner distance deviation, wheel flange wear, and track lateral tolerance, and is determined by combining the vehicle's lower clearance constraints, reaching a maximum of 320mm. Compared to traditional small-sized detection apertures, this large opening design significantly increases the effective sampling quantity. Under the same vehicle operating speed and sampling frequency, the sampling quantity of the two-array THDS11 and four-array THDS12 can reach 152 times and 305 times that of the original structure, respectively.

[0059] To compensate for the impact of the large opening design on structural strength, the scheme simultaneously optimized the load transfer path and strengthened key structural components. On the one hand, the bearing surface 7 of the spring bearing platform and the figure-eight straight segment 4 were set as parallel structures to avoid abrupt changes in cross-section and structural inconsistencies, ensuring smooth load transfer and coordinated structural deformation. On the other hand, for the axle box skirt 8, a structure with an inverted "L" shape cross-section was adopted, combined with discontinuous figure-eight reinforcing ribs 9 in the middle, to compensate for the weakening of vertical bending stiffness caused by the large opening layout. At the same time, a semi-closed grid-shaped anti-crushing structure 10 was set at the lower part of the primary spring bearing platform to effectively improve the local compressive bearing capacity of the bearing platform and ensure that the axle box 1 meets the strength requirements under all working conditions and throughout its entire life cycle.

[0060] Overall, this large-aperture axle box 1 can simultaneously meet the full-spot direct detection requirements of both two-array and four-array THDS equipment, completely eliminating the temperature conduction error caused by indirect detection in traditional circular axle box 1. The significantly increased sampling quantity can more comprehensively and realistically reflect the thermal distribution state of the bearing body, effectively improving the timeliness and accuracy of axle temperature warning, providing reliable protection for the safe operation of railway freight cars. At the same time, the structural design takes into account both manufacturability and engineering adaptability, and has good promotion and application value.

[0061] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A large-opening axle box body, used in welded frame bogies for railway freight cars, characterized in that: The transverse geometric cross-section of the axle box body (1) is a composite curve structure, including a circular arc saddle surface (2), a tangent straight line segment (3), and a figure-eight straight line segment (4) connected in sequence; The arc-shaped saddle surface (2) is used to cooperate with the outer ring of the bearing to transmit vertical load. The tangent straight segment (3) is tangentially connected to the lower end of the arc-shaped saddle surface (2). The figure-eight straight segment (4) is connected to the lower end of the tangent straight segment (3) and extends downward and outward. The lower end of the figure-eight straight segment (4) is transitionally connected to the spring support of the axle box body (1). The lower part of the axle box (1) forms a large-aperture detection opening (5), and the detection beam of the infrared shaft temperature detection system (6) probes the outer ring surface of the bearing inside the large-aperture detection opening (5) in the form of a full-spot.

2. The large-opening axle box body according to claim 1, characterized in that: The angle between the figure-eight straight segment (4) and the central axis of the cross section of the axle box (1) is 45°, and the angle is compatible with the detection elevation angle and horizontal angle parameters of the infrared axle temperature detection system (6).

3. The large-opening axle box body according to claim 1, characterized in that: The maximum longitudinal dimension of the large-aperture detection opening (5) is 530mm, which satisfies the requirement that the longitudinal displacement of the infrared shaft temperature detection system (6) reaches 160mm for full-spot direct detection.

4. The large-opening axle box body according to claim 1, characterized in that: The maximum lateral dimension of the large-aperture detection opening (5) is 320mm, covering the full spot detection range of the infrared shaft temperature detection system (6) under the condition of maximum lateral displacement of the wheelset.

5. A large-opening axle box body according to claim 1, characterized in that: The bearing surface (7) is provided on the spring support of the axle box body (1), and the bearing surface (7) is arranged parallel to the figure-eight straight segment (4).

6. A large-opening axle box body according to claim 1, characterized in that: The axle box body (1) extends longitudinally along the vehicle and is laterally offset to form an axle box skirt (8), the cross-section of which has an inverted "L" shape.

7. A large-opening axle box body according to claim 6, characterized in that: The middle part of the axle box skirt (8) is provided with discontinuous V-shaped reinforcing ribs (9).

8. A large-opening axle box body according to claim 1, characterized in that: The lower part of the primary spring support of the axle box body (1) is provided with a semi-closed grid-shaped anti-crushing structure (10).

9. A large-opening axle box body according to claim 1, characterized in that: The infrared axial temperature detection system (6) includes a two-array THDS (11) and a four-array THDS (12), and the large-aperture detection opening (5) simultaneously satisfies the full-spot direct detection of both the two-array THDS (11) and the four-array THDS (12).

10. A large-opening axle box body according to claim 1, characterized in that: Transition arcs are provided at the junctions of the arc-shaped saddle surface (2) and the tangent straight line segment (3), and at the junctions of the tangent straight line segment (3) and the figure-eight straight line segment (4).

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