Flywheel Module Hydraulic Accumulator for Hybrid Start-Stop
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing flywheel modules in vehicle transmission systems are complex and inefficient, leading to energy losses and inability to start the vehicle in hybrid applications due to lack of pressure when the driving source is switched off.
Innovation Solution
Incorporating a hydraulic buffer and an electromotor to downsize the hydraulic pump, along with a freewheel bearing to allow the pump to be electrically driven beyond the input shaft speed, and using a hydraulic accumulator to provide pressure when the driving source is off, while also simplifying the coupling mechanisms with splines and reducing gearing complexity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If the hydraulic pump is directly connected to the node and over-dimensioned to ensure sufficient flow, then the flow requirement is met, but energy losses increase and the pump produces more losses than necessary
Solution Approach 1:
The hydraulic accumulator is pre-charged with hydraulic fluid under pressure before the driving source is switched off. This preliminary action ensures that when the driving source is off, the accumulator can immediately provide the necessary hydraulic pressure and flow for vehicle launch without requiring an oversized pump to continuously maintain pressure.
2Use of energy by moving object
If the driving source is switched off in hybrid applications, then fuel consumption is reduced, but no pressure is available for enabling the launch of the vehicle
Solution Approach 1:
The hydraulic accumulator is pre-charged with hydraulic fluid under pressure before the driving source is switched off. This preliminary action ensures that when the driving source is off, the accumulator can immediately provide the necessary hydraulic pressure and flow for vehicle launch without requiring an oversized pump to continuously maintain pressure.
Solution Approach 2:
The hydraulic accumulator acts as an intermediary energy storage device between the driving source and the hydraulic pump. It stores hydraulic pressure and releases it when needed, decoupling the pump operation from the driving source status and ensuring reliable vehicle launch capability even when the driving source is off.
3Loss of energy
If the pump is down-sized to reduce energy losses, then energy efficiency improves, but insufficient flow is produced during normal working conditions
Solution Approach 1:
The hydraulic accumulator is pre-charged with hydraulic fluid under pressure before the driving source is switched off. This preliminary action ensures that when the driving source is off, the accumulator can immediately provide the necessary hydraulic pressure and flow for vehicle launch without requiring an oversized pump to continuously maintain pressure.
Solution Approach 2:
The system changes the operational parameters of the pump by using the accumulator to supplement flow during peak demand periods. This allows the pump to operate at lower, more efficient parameters during normal conditions while still meeting high flow requirements when the accumulator releases stored pressure.
4Reliability
If the known flywheel module configuration is used, then the transmission system is complete, but the device complexity increases
Solution Approach 1:
The patent extracts the hydraulic accumulator from the complex known flywheel module configuration and positions it as a separate component connected to the node. This extraction simplifies the overall system architecture by separating the pressure storage function from the flywheel mechanism, reducing device complexity while maintaining transmission system completeness.
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 energy waste, ensures sufficient flow for normal operations, and enables vehicle launch without direct pressure from the pump, improving efficiency and functionality in hybrid start-stop scenarios.
Implementation Method 1
the flywheel module comprises a hydraulic buffer which is connected to the node
Implementation Method 2
The flywheel module further preferably comprises an electromotor which can drive the pump
Implementation Method 3
a freewheel bearing which is positioned between on the one hand the pump plus electromotor and the node on the other
Data Source
Figure 1~2
Figure 3~4
Figure 5~6
AI summary
A flywheel module (9) comprises a coupling unit (11) which has an input shaft (15) and an output shaft (17). This coupling unit (11) has a first coupling (23) of which a first coupling half (25) can be connected to a combustion engine (3) and a second coupling half (27) can be connected to a continuously variable transmission (7). The flywheel module (9) further comprises a flywheel unit (13) which has an in/output (28) and is formed by a flywheel (29) and a reduction gear unit (31) connected to the flywheel (29). This flywheel unit (13) is exclusively connected to the in/output (28) via the coupling unit (11).