Shaft system structure of gearbox driving shaft

Abstract

The utility model relates to a shaft system structure of a gearbox driving shaft, and belongs to the field of gearboxes. According to the technical scheme, the gearbox driving shaft system structure comprises a driving shaft, the driving shaft comprises a spline section and an optical axis section, a blocking structure is arranged between the spline section and the optical axis section, and the outer diameter of the blocking structure is larger than the large diameter of the spline section; a first driving gear is installed on the spline section, an inner spline is arranged in an inner hole of the first driving gear, a diameter expanding structure is arranged in an inner hole of the first end of the first driving gear, the inner diameter of the diameter expanding structure is matched with the outer diameter of the blocking structure, and a positioning ring is concentrically installed at the second end of the first driving gear. And the inner diameter of the positioning ring is matched with the large diameter of the spline section. The expanding structure skips the tail end of the spline section to be matched with the blocking structure, the positioning ring is in large-diameter fit with the spline section, and the influence of clearance change at the two ends of the spline pair is effectively eliminated. The positioning ring and the blocking structure are easy to machine, so that the assembly stability of the gearbox gear and the gear shaft is remarkably improved, and the service life of a gearbox is prolonged.

Description

Technical Field

[0001] This utility model relates to the field of gearboxes, and in particular to a gearbox drive shaft system structure. Background Technology

[0002] The gearbox is an important component of a vehicle's powertrain. It is responsible for transmitting the power output from the engine to the axle. During the power transmission process, it changes the gear ratio and forms various gear ratio combinations through the meshing of gears of different sizes, thereby controlling the vehicle's torque.

[0003] The gearbox internally consists of a gear train structure. During assembly, the gears are mostly connected to the gear shaft via spline pairs. A spline pair comprises an external spline on the shaft and an internal spline extending from the gear's inner bore. The external spline has multiple circumferentially distributed key teeth, while the internal spline has corresponding keyways. During operation, the meshing of these two splines achieves circumferential fixation of the shaft and hub, as well as torque transmission. It can also be designed to allow for axial movement or fixation. Spline pairs offer significant advantages: high torque capacity, high centering accuracy, uniform stress distribution, and long service life.

[0004] During the machining of external splines on the shaft, one end of the spline teeth is located at the end of the shaft body, while the other end gradually transitions to the smooth shaft portion of the shaft body. At the end connected to the smooth shaft, due to limitations in the machining process, the tooth root of the spline gradually rises, presenting a slope shape in the shaft cross-section. This results in a decrease in the clearance between the internal and external spline teeth when the internal spline of the gear is close to this end, while the clearance at the other end is greater than that at the first end. Consequently, during the meshing process of the gearbox's drive gear, the spline end of the gear is prone to alternating oscillation, causing slippage on the meshing tooth surface. This, combined with scuffing and pitting corrosion on the tooth surface, accelerates tooth surface damage, thus affecting the normal operation and service life of the gearbox. Utility Model Content

[0005] This invention addresses the problem in current gearboxes where the gears mounted at the root of the external spline on the gear shaft are affected by the spline machining shape, resulting in uneven clearance at both ends, alternating oscillation, slippage of the meshing tooth surface, and scuffing, which, combined with pitting, accelerates tooth surface damage. The invention provides a gearbox drive shaft system structure.

[0006] To solve the above problems, the technical solution adopted by this utility model is a gearbox drive shaft system structure, including a drive shaft, which includes a splined section and a smooth shaft section. A blocking structure is provided between the splined section and the smooth shaft section, and the outer diameter of the blocking structure is larger than the major diameter of the splined section. A first drive gear is mounted on the splined section. The inner hole of the first drive gear has an internal spline, and the inner hole at the first end of the first drive gear has an expansion structure. The inner diameter of the expansion structure matches the outer diameter of the blocking structure. A positioning ring is concentrically mounted at the second end of the first drive gear, and the inner diameter of the positioning ring matches the major diameter of the splined section. In this solution, independent mating structures are provided at both ends of the internal spline of the first drive gear. On the one hand, the expansion structure directly matches the blocking structure on the drive shaft, skipping the end of the splined section. On the other hand, the positioning ring matches the major diameter of the splined section, i.e., the external spline, eliminating the influence of clearance changes at both ends of the spline pair. The positioning ring and the blocking structure are easy to process, which is conducive to strict precision control, thereby improving the assembly stability of the gearbox gear and gear shaft and increasing the service life of the gearbox.

[0007] As a preferred implementation of the gearbox drive shaft system structure, the major diameter of the splined section is smaller than the outer diameter of the smooth shaft section, and the blocking structure is a shoulder disposed between the splined section and the smooth shaft section, the outer diameter of which is smaller than the outer diameter of the smooth shaft section. This design makes the shaft system structure more compact and reasonable. The shoulder, as a blocking structure, has a mature and reasonable processing technology, making it easy to ensure dimensional accuracy, further improving the reliability and stability of the shaft system structure, effectively avoiding component interference and damage caused by unreasonable structure, and ensuring smooth power transmission.

[0008] As a preferred implementation of the gearbox drive shaft system structure, in the axial direction, the internal spline of the first drive gear includes a first internal spline end and a second internal spline segment. The first internal spline segment is close to the first end of the first drive gear, and the second internal spline segment is close to the second end of the first drive gear. The tooth tip height of the first internal spline segment is smaller than that of the second internal spline segment, and the first internal spline segment forms the expanded diameter structure. This design cleverly utilizes the difference in tooth tip height of the internal splines to form the expanded diameter structure, which precisely matches the blocking structure, further optimizing the connection method between the gear and the shaft and enhancing the tightness and stability of the fit.

[0009] As a preferred implementation of the transmission drive shaft system structure, a second drive gear is also installed on the splined section, located at the end of the splined section away from the optical shaft section. The multi-gear configuration enriches the transmission ratio selection of the transmission, meets the power requirements of the vehicle under more operating conditions, and improves the vehicle's versatility and adaptability.

[0010] As a preferred embodiment of the transmission drive shaft system structure, a spacer is provided between the first drive gear and the second drive gear. The first end of the spacer abuts against the side end face of the positioning ring, and the second end of the spacer abuts against the side end face of the second drive gear. The spacer effectively ensures that the axial distance between the two drive gears is precisely fixed, avoiding axial movement of the gears during operation, improving the smoothness of gear transmission, reducing poor meshing and increased wear caused by changes in gear spacing, and extending the service life of the gears and the entire transmission.

[0011] As a preferred embodiment of the gearbox drive shaft system structure, a countersunk hole is formed at the second end of the first drive gear. The diameter of the countersunk hole is larger than the diameter of the center hole of the first drive gear, and the locating ring is installed in the countersunk hole. The installation of the locating ring is more stable and reliable, improving the assembly accuracy between the locating ring and the first drive gear, and further enhancing the stability of the entire shaft system structure.

[0012] As a preferred embodiment of the transmission drive shaft system structure, a transmission gear set is mounted on the optical shaft section via bearings. The transmission gear set includes a first gear disc and a second gear disc coaxially and fixedly connected. The diameter of the first gear disc is larger than the diameter of the second gear disc, and in the axial direction, the first gear disc is positioned close to the first drive gear. The transmission gear set further expands the transmission ratio range of the transmission, and the interlocking of gear discs of different diameters enables more precise power adjustment.

[0013] As a preferred embodiment of the gearbox drive shaft system structure, a locking gear is fixedly provided at the end of the optical shaft segment away from the spline segment.

[0014] As a preferred embodiment of the gearbox drive shaft system structure, the locking gear and the drive shaft are an integral structure. This integrated design reduces the number of connection points between components, improves the overall integrity and strength of the structure, reduces the risk of failure due to loose connections, simplifies machining and assembly processes, improves production efficiency, and helps ensure consistent product quality.

[0015] As a preferred implementation of the transmission drive shaft system structure, the fit clearance range between the inner diameter of the locating ring and the major diameter of the spline segment is the same as the clearance range between the inner diameter of the expansion structure and the outer diameter of the blocking structure, both being 2-3 microns. Maintaining the clearances on both sides within the same small range further improves the assembly accuracy and operational stability of the shaft system structure, extends the service life of the transmission, and enhances the overall performance of the vehicle.

[0016] As can be seen from the above technical solutions, the advantages of this utility model are as follows: This solution features a unique mating structure at both ends of the spline inside the first drive gear. During gearbox operation, the spline clearance changes with operating conditions; this structure eliminates the impact of clearance variations. Through mechanical structure, the gear and gear shaft maintain a precise relative position, improving assembly stability and extending the gearbox's service life. The shaft shoulder acts as a blocking structure, planning the shaft system layout to ensure a compact and reasonable shaft system and smooth power transmission. The height difference of the internal spline tooth tips forms an expansion structure, optimizing the tightness of the gear-shaft connection and making power transmission more direct and efficient. The multi-gear configuration provides the gearbox with a wide range of transmission ratios. Whether the vehicle is frequently starting and stopping in urban congestion or cruising at high speeds, it can match appropriate transmission ratios to meet diverse operating conditions, improving vehicle versatility and adaptability. The spacer fixes the distance between the drive gears, preventing poor gear meshing, reducing wear, and extending the gearbox's lifespan. The countersunk hole mounting locating ring enhances shaft system stability. The transmission gear set widens the transmission ratio range, enabling fine power adjustment to meet the power output requirements of different scenarios. The integrated structure of the locking gear and drive shaft enhances structural integrity and strength, simplifies manufacturing processes, and ensures consistent product quality. Precise control of the fit clearance improves the assembly and operational stability of the shaft system, comprehensively enhancing gearbox performance and lifespan, and ensuring stable and efficient operation of the gearbox under various working conditions. Attached Figure Description

[0017] To more clearly illustrate the technical solution of this utility model, the drawings used in the description will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the gearbox drive shaft system structure according to a specific embodiment of the present invention.

[0019] Figure 2 This is a schematic diagram of the assembly structure of the first drive gear and the positioning ring in the drive shaft system structure of the gearbox according to a specific embodiment of the present invention.

[0020] Explanation of main figure symbols

[0021] 1. Drive shaft, 11. Spline section, 12. Optical shaft section, 13. Shaft shoulder, 2. First drive gear, 3. Locating ring, 4. Second drive gear, 5. Spacer, 6. Gear set, 7. Locking gear. Detailed Implementation

[0022] To make the objectives, features, and advantages of this utility model more apparent and understandable, the technical solutions of this utility model will be clearly and completely described below with reference to the accompanying drawings of the specific embodiments. Obviously, the embodiments described below are only some embodiments of this utility model, and not all embodiments. Based on the embodiments of this patent, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this patent.

[0023] This solution eliminates the impact of spline clearance variations by incorporating unique mating structures at both ends of the spline within the first drive gear, improving the assembly stability of the gear and gear shaft, and extending the service life of the transmission. The shaft shoulder acts as a blocking structure, ensuring a compact and rational shaft system and smooth power transmission. The difference in the tip height of the internal spline teeth creates an expanded diameter structure, optimizing the tightness of the gear-shaft connection. Multiple gears provide a variety of transmission ratios to meet diverse operating conditions, improving vehicle versatility and adaptability. Spacers precisely fix the drive gear spacing, reducing poor gear meshing and wear, and extending transmission life. Countersunk mounting locating rings enhance shaft system stability. The transmission gear set expands the transmission ratio range, enabling precise power adjustment. The locking gear and drive shaft are integrated into a single structure, improving structural integrity and strength, simplifying the process, and ensuring consistent product quality. Precise control of the mating clearance further enhances the assembly and operational stability of the shaft system, improving transmission performance and lifespan.

[0024] The above description of the disclosed embodiments enables those skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A gearbox driveshaft axle system comprising a driveshaft (1), characterized in that, The driving shaft (1) comprises a spline section (11) and a smooth shaft section (12), a blocking structure is arranged between the spline section (11) and the smooth shaft section (12), and the outer diameter of the blocking structure is greater than the large diameter of the spline section (11); The first driving gear (2) is mounted on the spline section (11), the inner hole of the first driving gear (2) is provided with internal splines, the inner hole of the first end of the first driving gear (2) is provided with an expansion structure, the inner diameter of the expansion structure matches the outer diameter of the blocking structure, the second end of the first driving gear (2) is coaxially provided with a positioning ring (3), and the inner diameter of the positioning ring (3) matches the large diameter of the spline section (11).

2. A gearbox drive shaft arrangement according to claim 1, wherein, The large diameter of the spline section (11) is smaller than the outer diameter of the smooth shaft section (12), the blocking structure is a shaft shoulder (13) arranged between the spline section (11) and the smooth shaft section (12), and the outer diameter of the shaft shoulder (13) is smaller than the outer diameter of the smooth shaft section (12).

3. A gearbox drive shaft arrangement according to claim 1, wherein, In the axial direction, the internal splines of the first driving gear (2) comprise a first internal spline section and a second internal spline section, the first internal spline section is close to the first end of the first driving gear (2), the second internal spline section is close to the second end of the first driving gear (2), the tooth crest height of the first internal spline section is smaller than the tooth crest height of the second internal spline section, and the first internal spline section forms the expansion structure.

4. A gearbox drive shaft arrangement according to claim 1, wherein, The spline section (11) is further provided with a second driving gear (4), and the second driving gear (4) is located at one end of the spline section (11) away from the smooth shaft section (12).

5. A gearbox drive shaft arrangement according to claim 4, wherein, A spacer sleeve (5) is arranged between the first driving gear (2) and the second driving gear (4), the first end of the spacer sleeve (5) abuts against the side end face of the positioning ring (3), and the second end of the spacer sleeve (5) abuts against the side end face of the second driving gear (4).

6. A gearbox drive shaft arrangement according to claim 1, wherein, The second end of the first driving gear (2) is provided with a counterbore, the diameter of the counterbore is greater than the diameter of the center hole of the first driving gear (2), and the positioning ring (3) is mounted in the counterbore.

7. A gearbox drive shaft arrangement according to claim 1, wherein, The smooth shaft section (12) is provided with a variable speed gear set (6) through a bearing, the variable speed gear set (6) comprises coaxially fixed first and second toothed discs, the diameter of the first toothed disc is greater than the diameter of the second toothed disc, and the first toothed disc is arranged close to the first driving gear (2) in the axial direction.

8. A gearbox drive shaft arrangement according to claim 7, wherein, One end of the smooth shaft section (12) away from the spline section (11) is fixedly provided with a locking gear (7).

9. A gearbox drive shaft arrangement according to claim 8, wherein, The locking gear (7) and the driving shaft (1) are an integral structure.

10. A gearbox drive shaft arrangement according to claim 1, wherein, The matching gap range between the inner diameter of the positioning ring (3) and the large diameter of the spline section (11) is the same as the gap range between the inner diameter of the expansion structure and the outer diameter of the blocking structure, and both are 2-3 wires.

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