Multi-Idle Shaft DCT Reduces Transmission Length
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Double clutch transmission (DCT) systems face challenges in minimizing length and weight to accommodate multiple shift-stages, particularly in hybrid vehicles where engine bay space is limited, leading to increased complexity and production costs.
Innovation Solution
The power transmission apparatus disperses forward third, fourth, sixth, and reverse speed shifting gears on three idle shafts, reducing the overall length and part count, utilizing first and second input shafts, shifting output devices, and idle units with synchronizers to achieve ten forward speeds and one reverse speed.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If multiple shift-stages are added to achieve more speeds, then the transmission ratio range and fuel efficiency are improved, but the length and weight of the transmission apparatus increase
Solution Approach 1:
The transmission apparatus is divided into multiple independent idle shafts (first idle shaft, second idle shaft, third idle shaft) that can be arranged in parallel. Each idle shaft carries specific shifting gears for different speed stages, segmenting the overall transmission structure. This segmentation allows the long transmission train to be distributed across multiple compact shafts, reducing the total length while maintaining all necessary speed ratios.
Solution Approach 2:
Instead of arranging all shifting gears in a single linear sequence along one shaft, the invention transitions to a multi-dimensional arrangement by introducing multiple parallel idle shafts. The shifting gears are distributed across these shafts in a two-dimensional layout, converting a long one-dimensional arrangement into a compact multi-dimensional structure, thereby reducing the overall length of the transmission apparatus.
2Productivity
If multiple shift-stages are added to achieve more speeds, then the transmission ratio range and fuel efficiency are improved, but the weight of the transmission apparatus increases
Solution Approach 1:
The transmission apparatus is divided into multiple independent idle shafts (first idle shaft, second idle shaft, third idle shaft) that can be arranged in parallel. Each idle shaft carries specific shifting gears for different speed stages, segmenting the overall transmission structure. This segmentation allows the long transmission train to be distributed across multiple compact shafts, reducing the total length while maintaining all necessary speed ratios.
Solution Approach 2:
Instead of arranging all shifting gears in a single linear sequence along one shaft, the invention transitions to a multi-dimensional arrangement by introducing multiple parallel idle shafts. The shifting gears are distributed across these shafts in a two-dimensional layout, converting a long one-dimensional arrangement into a compact multi-dimensional structure, thereby reducing the overall length of the transmission apparatus.
3Ease of manufacture
If the number of parts is reduced to minimize length and weight, then the installability and production cost are improved, but the complexity of achieving multiple shift-stages increases
Solution Approach 1:
Each idle shaft serves multiple functions: it carries specific shifting gears, provides a mounting structure for synchronizers, and acts as a power transmission path. The parallel idle shafts collectively provide all necessary speed ratios while maintaining a modular structure. This multi-functionality reduces the need for additional auxiliary parts and simplifies the overall design despite the multiple shift-stages.
Solution Approach 2:
The invention employs a nested arrangement where shifting gears are disposed on idle shafts that are themselves arranged in a compact configuration. The synchronizers and other components are integrated within the idle shaft assemblies, creating a nested structure that maximizes space utilization and reduces the total number of external parts needed.
Data Source
AI summary
Ten forward speeds and one reverse speed are achieved by a power transmission apparatus for a vehicle including a double clutch, a plurality of input, output, and idle shafts, a plurality of gears fixed to or rotatable on the shafts, a plurality of synchronizers selectively synchronizing gears to the shafts.