Transmission With Freewheel Ring Gears for Load Shifting
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional transmissions in the vehicle sector cannot be shifted under load, requiring an additional clutch to interrupt the drivetrain, which is costly and increases component failure and maintenance needs.
Innovation Solution
A transmission design featuring a first and second planetary gear with a common planet carrier, independent ring gears, and a freewheel mechanism, allowing power shifting by selectively connecting the ring gears to the transmission housing, enabling gear changes without additional measures.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If an additional clutch is provided to interrupt the drivetrain for gear shifting, then gear shifting can be achieved, but the device complexity and maintenance requirements increase
Solution Approach 1:
The patent merges the gear shifting function with the existing planetary gear set structure. The freewheel mechanism is integrated into the planetary gear set, allowing gear changes to be achieved through the interaction of existing components (ring gears, planet carriers, sun gears) rather than adding a separate clutch system. This combining of functions eliminates the need for additional clutch components while maintaining load-shifting capability.
Solution Approach 2:
The planetary gear set is designed to serve multiple functions: power transmission and gear shifting. By enabling the ring gears to be selectively connected or disconnected from the housing through the freewheel mechanism, the same gear set structure performs both torque transmission and gear ratio changes, eliminating the need for dedicated clutch components found in conventional transmissions.
2Ease of operation
If an additional clutch is provided to interrupt the drivetrain for gear shifting, then gear shifting can be achieved, but reliability decreases due to more failure points
Solution Approach 1:
The gear shifting function is merged into the planetary gear set structure itself, eliminating the need for separate clutch components. By using the freewheel mechanism to selectively engage or disengage ring gears from the housing, the system achieves gear changes without introducing additional failure-prone components, thereby improving reliability.
3Ease of operation
If the drivetrain is interrupted with a clutch for gear shifting, then gear changes can be made, but continuous power transmission is lost
Solution Approach 1:
The system dynamically switches between different gear ratios by selectively engaging or disengaging the freewheel mechanism. This dynamic engagement allows the ring gears to be connected to or disconnected from the housing on demand, enabling gear changes without interrupting the continuous flow of power through the planetary gear set.
Solution Approach 2:
The planetary gear set maintains continuous power transmission throughout the gear shifting process. The freewheel mechanism allows one ring gear to remain engaged with the housing while the other is disengaged, ensuring that power flow is never interrupted during gear changes, thus maintaining continuous useful action.
4Device complexity
If a conventional transmission design is used, then the structure is simple, but load-shifting capability is lost
Solution Approach 1:
The planetary gear set is designed with dynamic engagement capabilities through the freewheel mechanism. The ring gears can be selectively connected or disconnected from the housing based on operational requirements, allowing the transmission to adapt between different gear ratios and maintain load-shifting capability while preserving structural simplicity.
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
Enables easy and efficient gear shifting under load without additional components, reducing maintenance and component failure risks, and allowing continuous operation without interrupting the driving torque.
Implementation Method 1
The first ring gear of the first planetary gear set is mounted to the gearbox housing via a freewheel. This allows both a rotationally fixed connection between the first ring gear and the gearbox housing, as well as rotation of the first ring gear relative to the gearbox housing.
Data Source
Figure 1~2
AI summary
The invention relates to a transmission (1) comprising a first planetary transmission (2), a second planetary transmission (3) which has a different gear ratio than the first planetary transmission (2), and a transmission housing (21). The first planetary transmission (2) and the second planetary transmission (3) have a common planet carrier (4), and a first ring gear (5) of the first planetary transmission (2) is mounted on the transmission housing (21) via a freewheel (7) such that a force transmission into the transmission housing (21) occurs via the first ring gear (5) when the freewheel (7) is blocked and via a second ring gear (6) of the second planetary transmission (3) when the freewheel (7) is restored.