Hybrid Vehicle Lubrication Pump Control for Transmission Cooling
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In hybrid vehicle driving systems, when the neutral position is selected while driving, the lubrication pump is not driven, leading to inadequate lubrication and potential overheating due to the lack of mechanical rotation of the transmission components.
Innovation Solution
A hybrid vehicle driving system that includes a lubrication pump connected to the first input shaft, which can be driven by either the electric motor or the internal combustion engine when necessary, ensuring continuous lubrication by determining the lubricated state and rotating the first input shaft to activate the pump, even in neutral gear conditions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If the neutral position is selected while the vehicle is driven, then the vehicle can coast without engine power transmission, but the lubrication pump is not driven and the transmission components overheat
Solution Approach 1:
The control unit determines whether lubrication is necessary before the transmission components overheat, and activates the lubrication pump in advance by rotating the first input shaft through the electric motor or engine. This preliminary action prevents overheating while maintaining coasting capability.
Solution Approach 2:
The system uses the electric motor or engine itself to rotate the first input shaft and drive the lubrication pump, making the powertrain serve dual purposes: propulsion and lubrication maintenance during coasting.
2Reliability
If the lubrication pump is always driven to ensure continuous lubrication, then the transmission is adequately lubricated, but energy is wasted when lubrication is not necessary
Solution Approach 1:
The system dynamically adjusts the operation of the lubrication pump based on real-time conditions. The control unit determines whether lubrication is necessary and activates the pump only when needed, transforming the static always-on system into a dynamic conditional system that optimizes energy usage while maintaining reliability.
Solution Approach 2:
The system changes the operational parameters of the lubrication pump from continuous operation to conditional operation based on detected lubrication needs, thereby reducing energy consumption while maintaining adequate lubrication reliability.
3Reliability
If the first input shaft is rotated by the electric motor to drive the lubrication pump, then continuous lubrication is achieved during coasting, but additional energy consumption occurs
Solution Approach 1:
The electric motor, which is already part of the powertrain system, is utilized to rotate the first input shaft and drive the lubrication pump. This self-service approach uses existing system components rather than adding separate lubrication mechanisms, thereby achieving lubrication continuity while minimizing additional energy consumption.
4Productivity
If a dual-clutch transmission mechanism is used with selective engagement, then gear shifting efficiency is improved, but the lubrication pump may not be driven during neutral coasting
Solution Approach 1:
The first input shaft serves multiple functions: it transmits power during engine-driven operation and rotates the lubrication pump during electric motor-driven coasting. This multi-functionality ensures that the same component can maintain lubrication availability without compromising gear shifting efficiency of the dual-clutch transmission.
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 solution maintains the lubricated state of the transmission, reduces energy wastage, improves durability by synchronizing the rotation speed of the first input shaft with the third speed gear, and allows for air conditioning and lubrication of the electric motor, ensuring efficient operation and reduced friction.
Implementation Method 1
a lubrication pump (122) which is connected to the first main shaft (11) to thereby implement the lubrication of the transmission (20)
Implementation Method 2
the electric motor (7), and a transmission (20) having: a first input shaft (11) which is in engagement with the electric motor (7)
Implementation Method 3
an internal combustion engine (6), and a transmission (20) having: a first input shaft (11) which is in engagement with the electric motor (7)
Implementation Method 4
a first gear train including plural gears which are electively connected to the first input shaft (202a)
Data Source
AI summary
The present invention provides a hybrid vehicle driving system which can implement sufficient lubrication while a vehicle is being driven. A hybrid vehicle driving system 1 of the invention includes a lubrication pump 122 which is connected to a first input shaft 11 and which is adapted to lubricate a transmission 20 and a lubricated state determination unit 55 which determines a lubricated state of the transmission 20. When the lubricated state determination unit 55 determines that lubrication is necessary, the first input shaft 11 is rotated by an electric motor 7 so as to drive the lubrication pump 122, or the first input shaft 11 is rotated by an internal combustion engine 6 by engaging a first engaging and disengaging unit to thereby drive the lubrication pump 122.