Auxiliary Transmission Compact Layout for Power Unit Miniaturization
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing vehicle driving force transmission structures face challenges in miniaturization when an auxiliary transmission is provided as a separate body from the internal combustion engine, leading to increased overall size of the power unit.
Innovation Solution
A vehicle driving force transmission structure is designed with a main transmission having a transmission shaft group parallel to the crankshaft within the crankcase, and an auxiliary transmission as a separate body connecting to the main transmission, featuring a transmission driving mechanism, oil collecting ribs, and fuel supply ports to facilitate compact integration around the crankcase, eliminating the need for an oil pump space and allowing for integration of the output power shaft.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If an auxiliary transmission is provided as a separate body from the internal combustion engine, then the auxiliary transmission can be independently designed and maintained, but the overall size of the power unit increases
Solution Approach 1:
The auxiliary transmission is disposed within the periphery of the large rotational body (alternator), and the transmission driving mechanism is integrated below the large rotational body. This nesting arrangement allows the auxiliary transmission to occupy space that would otherwise be unused, achieving compact integration without increasing the overall power unit size.
Solution Approach 2:
The transmission shaft groups of both main and auxiliary transmissions are arranged parallel to each other and to the crankshaft, creating a multi-dimensional spatial arrangement. This allows efficient packing of transmission components in three-dimensional space around the large rotational body, minimizing the footprint while maintaining functional independence.
2Volume of moving object
If the auxiliary transmission is disposed compactly around the crankcase, then miniaturization of the power unit is achieved, but space for oil pump and fuel supply is limited
Solution Approach 1:
The auxiliary transmission case itself serves as the fuel supply system. Fuel supply ports are formed directly in the auxiliary transmission case, and oil collecting ribs guide lubricating oil to the transmission mechanisms. This eliminates the need for separate oil pumps and complex fuel supply components, achieving self-service lubrication and fuel delivery within the compact structure.
Solution Approach 2:
The auxiliary transmission case performs multiple functions: it houses the transmission mechanisms, serves as a fuel reservoir through integrated fuel supply ports, provides lubrication through oil collecting ribs, and supports the transmission shafts. This multi-functionality reduces the number of separate components needed, enabling compact disposition while maintaining complete oil supply and fuel delivery systems.
3Volume of moving object
If the transmission driving mechanism is disposed below the large rotational body, then compact integration is achieved, but accessibility for maintenance is reduced
Solution Approach 1:
The auxiliary transmission is designed as a separate body that can be independently removed from the power unit. The transmission case is separable from the crankcase, allowing the entire auxiliary transmission assembly to be extracted as one unit for maintenance. This segmentation enables compact integration during operation while facilitating easy removal and servicing without disassembling the entire power unit.
Data Source
AI summary
The vehicle driving force transmission structure of a power unit can include a main transmission having a transmission shaft group and parallel to a crankshaft and provided in a crankcase on the side of the crankshaft. The transmission structure can also include a large rotational body provided at an end of the crankshaft, and an auxiliary transmission provided as a separate body from and connecting to the main transmission. The auxiliary transmission has a transmission shaft group parallel to the transmission shaft group of the main transmission and disposed so as to form a periphery of the large rotational body. The auxiliary transmission includes a transmission driving mechanism disposed below the large rotational body.