Starting Clutch Oil Flow Control for Slip-State Lubrication
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional lubrication systems for power transmission units with wet-type friction clutches often fail to supply oil adequately to both the starting clutch and other elements, such as automatic transmissions, due to a constant total oil circulation, leading to insufficient lubrication and cooling, especially when the clutch is in a slipping engagement state.
Innovation Solution
A lubrication system with a controller-regulated first and second control valve, which adjusts the oil flow rate into and out of the friction clutch, ensuring appropriate oil supply irrespective of the clutch's engagement state, maintaining an oil-sealed condition and balancing inflow and outflow, and incorporating a hydraulic circuit with low and high flow rate passages to manage oil distribution effectively.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a large amount of oil is supplied preferentially to the start clutch when it is in a slipping connect state, then the lubrication and cooling of the start clutch is improved, but the oil supply to other elements such as the automatic transmission becomes insufficient
Solution Approach 1:
The patent applies dynamics by making the oil supply system adjustable based on operating conditions. The control valve dynamically changes the flow rate of oil supplied to the start clutch according to the slip angular speed, transitioning between different supply modes (minimum supply at low slip speed, increased supply at high slip speed) to optimize lubrication while maintaining overall system balance
Solution Approach 2:
The patent changes the flow rate parameter of oil supply based on the operating state of the start clutch. By detecting slip angular speed and adjusting the control valve accordingly, the system varies the oil flow rate parameter to match the actual lubrication needs, preventing both over-supply and under-supply conditions
2Device complexity
If the total amount of oil circulating within the hydraulic circuits is kept constant, then the system simplicity is maintained, but the oil may not be supplied sufficiently to all elements when the start clutch requires preferential supply
Solution Approach 1:
The patent changes the flow rate parameter of oil supply based on the operating state of the start clutch. By detecting slip angular speed and adjusting the control valve accordingly, the system varies the oil flow rate parameter to match the actual lubrication needs, preventing both over-supply and under-supply conditions
Data Source
AI summary
A lubrication system for a power transmission unit that supplies oil to a starting clutch in an appropriate amount irrespective of an engagement state of the starting clutch. When the friction clutch is completely engaged or disengaged, a first control valve is brought into a low inflow rate mode, and the second control valve is brought into a low outflow rate mode. When the friction clutch is engaged while causing a slip the first control valve is brought into a high inflow rate mode, and the second control valve is brought a high outflow rate mode.