CVT Shaft Offset Layout for Compact Power-Split Packaging
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Continuously variable transmissions (CVTs) face challenges in achieving a compact design due to limited installation space, particularly in the overall length and height, which restricts their application in vehicles and other machines.
Innovation Solution
A compact design for CVTs is achieved by offsetting and geometrically arranging the input and output shafts horizontally and vertically, integrating a hydrostatic transmission parallel to the variator transmission, reducing tooth engagements, and utilizing a one-piece housing with a flat bearing plate for modular integration.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If the number of tooth engagements between gearwheels is reduced to increase efficiency, then energy loss decreases, but the installation space requirements become more complex
Solution Approach 1:
The patent offsets the output shaft horizontally and vertically with respect to the input shaft, transitioning from a conventional aligned configuration to a three-dimensional offset arrangement. This dimensional change allows the power flow to be split between hydrostatic and mechanical branches without increasing the number of tooth engagements, thereby reducing energy loss while managing installation space complexity through spatial optimization
2Length of moving object
If the overall length of the transmission is reduced to save installation space, then the installation space decreases, but the shaft positions become more constrained
Solution Approach 1:
The patent employs horizontal and vertical offsetting of shafts to achieve compact overall length while maintaining shaft position flexibility. By utilizing three-dimensional spatial arrangement rather than linear alignment, the design reduces the transmission's length in the vehicle direction while preserving the necessary adaptability for power distribution between hydrostatic and mechanical branches
Solution Approach 2:
The patent integrates multiple functional components including the variator transmission, hydrostatic transmission, and clutch assemblies within a compact housing. The components are nested and arranged to optimize space utilization, with the offset shaft configuration allowing efficient packaging that maintains both compact length and shaft position flexibility
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This configuration reduces installation space, enabling efficient power distribution, improved efficiency, noise reduction, and enhanced ride comfort while allowing for additional modules and standardization of components.
Implementation Method 1
a hydrostatic transmission (60) which is arranged geometrically parallel to the variator transmission (50) in a side view in the installation position
Implementation Method 2
the input shaft (20) is connected to the intermediate shaft (40) via one or more tooth engagements by means of gearwheels
Data Source
AI summary
A continuously variable transmission has an input shaft, an output shaft, an intermediate shaft connected to the output shaft and to the input shaft via one or more tooth engagements, a variator transmission arranged on the intermediate shaft, a hydrostatic transmission, a housing, and a bearing plate. The housing at least partially encloses the input shaft, the output shaft, and the intermediate shaft. The hydrostatic transmission is arranged geometrically parallel to the variator transmission, and the power flow can be split therebetween. The output shaft is offset horizontally and vertically with respect to the input shaft. The housing is in one piece and open on one side. The components are held in the housing by the bearing plate in the mounted state. One or more of the housing and the bearing plate have flat surfaces on outer sides, which are configured to fasten module components on the continuously variable transmission.