Vehicle Gearbox Axial Coupling Eliminating Reverse Gear Weight
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Solution Overview
Problem
Existing gearboxes for heavy vehicles face issues with slow shift times, high energy consumption, noise, and maintenance costs due to complex synchronisation devices and the presence of a reverse gear in the main gearbox, which increases weight and fuel consumption.
Innovation Solution
A gearbox design featuring axially shiftable coupling sleeves that allow for efficient torque transmission and eliminate the need for a reverse gear in the main gearbox, incorporating oblique teeth and splines for reduced noise and stress, and a simplified construction for quicker shifting and easier repair.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a reverse gear is included in the main gearbox, then the vehicle can achieve reverse motion capability, but the weight of the main gearbox increases and fuel consumption increases
Solution Approach 1:
The transmission system is divided into two separate gearboxes: the main gearbox handles forward gears only, and a separate range gearbox handles reverse gear and range changes. This segmentation removes the reverse gear from the main gearbox, reducing its weight while maintaining the vehicle's reverse motion capability through the range gearbox.
2Reliability
If complex synchronisation devices are used in the gearbox, then synchronous gear shifting can be achieved, but the shift time increases and energy consumption increases
Solution Approach 1:
The complex synchronisation devices are removed from the range gearbox. Instead, a simplified shifting mechanism using coupling sleeves and splines is implemented, which achieves gear changes without traditional synchronisers, thereby reducing shift time and energy consumption while maintaining reliable gear engagement.
Solution Approach 2:
Instead of using synchronisation rings that engage teeth to achieve synchronous shifting, the patent inverts the approach by using free-wheeling coupling sleeves with splines that allow torque transmission without requiring tooth engagement synchronisation. This eliminates the need for complex synchronisation mechanisms.
3Ease of manufacture
If traditional gear design with straight teeth is used, then manufacturing is simpler, but noise emission increases and stress on components increases
Solution Approach 1:
The gear teeth are designed with oblique (helical) configuration instead of straight teeth. This parameter change in tooth geometry reduces noise emission and distributes stress more evenly across the gear mesh, while the manufacturing process remains feasible through standard helical gear cutting methods.
4Volume of moving object
If the range gearbox uses a compact design, then space is saved, but the coupling sleeves require longer axial strokes for shifting
Solution Approach 1:
The coupling sleeves are designed with splines that engage in a radial direction rather than requiring long axial strokes. This dimensional change in the engagement mechanism allows the sleeves to achieve secure coupling with minimal axial movement, enabling a compact gearbox design while maintaining effective torque transmission.
Data Source
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AI summary
The invention relates to a gearbox (2) for vehicles, comprising a planetary gearbox (14) with a ring gear (22), a sun wheel (18) and a planetary wheel carrier (20), on which at least one planetary wheel (24) is mounted in a rotatable manner, which ring gear (22) and sun wheel (18) engage with the at least one planetary wheel (24) through teeth (32); and a first axially shiftable coupling sleeve (40), which in a first gear position is arranged to disconnect an input shaft (16) to the gearbox (2) from the planetary wheel carrier (20), and in a second gear position is arranged to connect the input shaft (16) with the planetary wheel carrier (20). A second axially shiftable coupling sleeve (42) is arranged to connect a gearbox house (12) surrounding the planetary gearbox (14) with the ring gear (22) in the first gear position, and arranged to disconnect the gearbox house (12) from the ring gear (22) in the second gear position,. A third axially shiftable coupling sleeve (43) is arranged to connect the ring gear (22) with an output shaft (28) in a third gear position, wherein the second axially shiftable coupling sleeve (42) is arranged to connect the planetary wheel carrier (20) with the gearbox house (12) in the third gear position The invention also relates to a vehicle (1) comprising such a gearbox (2).