Hybrid Powertrain With Center Synchronizing Unit
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional hybrid powertrains with engine clutches incur high costs and limited motor performance due to synchronized engine and motor speeds, complex power transmission paths during regenerative braking, which deteriorate efficiency.
Innovation Solution
A hybrid powertrain design that excludes engine clutches, featuring a center synchronizing unit and variable power transmission mechanism with conical frictional clutches, allowing independent motor control and shorter power transmission paths, enabling efficient regenerative braking and improved EV mode performance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If an engine clutch is used to connect the engine and motor, then the connection can be interrupted, but the manufacturing cost and weight increase
Solution Approach 1:
The patent removes the engine clutch from the powertrain system entirely. Instead of using a clutch to interrupt the connection between engine and motor, the system uses a direct mechanical connection through the transmission input shaft, allowing the connection to be maintained while using electronic control to manage power flow between engine and motor.
Solution Approach 2:
The transmission input shaft serves multiple functions: it connects the engine to the transmission, connects the motor to the transmission, and provides a common mounting axis for both power sources. This multi-functional design eliminates the need for separate clutch mechanisms while maintaining system reliability.
2Weight of moving object
If an engine clutch is used to connect the engine and motor, then the connection can be interrupted, but the weight increases
Solution Approach 1:
The engine clutch is completely removed from the system, eliminating its weight contribution. The connection reliability function is achieved through the direct mechanical coupling of the transmission input shaft with both engine and motor, which provides inherent structural reliability without additional weighting components.
3Device complexity
If the motor is located close to the input side of the transmission, then the hybrid powertrain can be configured, but the power transmission path becomes complex during regenerative braking
Solution Approach 1:
Instead of having the motor assist the engine at the input side and then transmitting power through the gear train to the output, the patent positions the motor to directly drive the transmission input shaft. During regenerative braking, this configuration allows the motor to directly receive kinetic energy from the drivetrain and convert it to electrical energy, creating a simplified and more efficient power flow path.
4Productivity
If the gear-shift map is set according to an optimum operation point of the engine, then the engine operates efficiently, but the motor performance cannot be sufficiently achieved
Solution Approach 1:
The system dynamically switches between engine-driven and motor-driven modes based on operating conditions. The transmission input shaft can be driven by the engine through the clutch, by the motor directly, or by both simultaneously, allowing the system to adapt to different power demands and optimize the performance of whichever power source is most efficient at that moment.
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 design reduces manufacturing costs and weight, enhances motor and engine operation, and improves powertrain efficiency by allowing independent motor control and shorter power transmission paths during regenerative braking, thus enhancing overall hybrid powertrain performance.
Implementation Method 1
a servo clutch configured to continuously vary a frictional force between the motor input shaft and the variable driving gear through an operation of the center synchronizing unit
Data Source
AI summary
A hybrid powertrain for a vehicle may include a first input shaft selectively connectable to an engine through a first clutch; a second input shaft selectively connectable to the engine through a second clutch and mounted to be coaxial with the first input shaft; a motor input shaft mounted to be coaxial with the first input shaft and to which a motor is connected; a first output shaft and a second output shaft each mounted in parallel to the first input shaft and the second input shaft; a center synchronizing unit mounted between the first input shaft and the motor input shaft and configured to interrupt a connection between the first input shaft and the motor input shaft; a plurality of pairs of circumscription gears configured to form a series of shift ratios used for driving of the vehicle; and a variable transmission mechanism.