Variable Valve Duration and Lift System for Engine Weight Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing engine technologies face challenges in optimizing valve operation based on engine speed, requiring complex designs for variable valve timing and lift, which can increase weight, driving resistance, and production costs.
Innovation Solution
A variable valve duration/variable valve lift system with a simple construction that includes a camshaft, adjustable cam portions, a solenoid valve, and a position controller to change the relative phase angle and hydraulic pressure, allowing for simultaneous adjustment of valve opening duration and lift according to engine operation conditions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If variable valve timing and lift systems are implemented to optimize valve operation based on engine speed, then valve operation efficiency is improved, but device complexity and weight increase
Solution Approach 1:
The patent combines variable valve timing and variable valve lift functions into a single integrated system. The camshaft assembly includes both timing adjustment capability (through the inner bracket and slider housing mechanism) and lift control (through the valve lift component with plunger and lock pin). This merging of functions reduces the number of separate components and simplifies the overall system construction while maintaining both timing and lift variability.
Solution Approach 2:
The camshaft assembly serves multiple functions simultaneously: it provides fixed timing operation, variable timing operation (through rotation of inner bracket relative to slider housing), fixed lift operation, and variable lift operation (through plunger displacement in valve lift). This multi-functionality allows a single component to replace what would traditionally require multiple separate systems, reducing complexity.
2Manufacturing precision
If complex variable valve timing systems are designed to achieve optimal valve operation, then valve timing precision is improved, but production costs increase
Solution Approach 1:
The timing adjustment mechanism is segmented into discrete positional states (first position for fixed timing, second position for variable timing) achieved through the slider housing and inner bracket configuration. The valve lift is similarly segmented into fixed and variable states through the plunger and lock pin mechanism. This segmentation allows for precise timing control while using simpler, more manufacturable components compared to continuously variable systems.
3Adaptability or versatility
If additional components are added to achieve variable valve duration and lift, then valve control flexibility is improved, but engine weight increases
Solution Approach 1:
The valve lift component is nested within the bridge structure, with the plunger and lock pin mechanism integrated into the existing valve train components. The inner bracket and slider housing are nested within the camshaft assembly. This nesting approach allows variable valve duration and lift functionality to be achieved by integrating control mechanisms into existing structural components rather than adding entirely separate systems, thereby minimizing weight increase.
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 system reduces engine weight and driving resistance, enhances productivity, and lowers production costs by allowing for flexible valve operation without excessive modification to existing engines, while maintaining efficient air or air/fuel mixture supply across varying conditions.
Implementation Method 1
a solenoid valve configured to selectively supply hydraulic pressure, a position controller configured to selectively change a position of the slider housing according to the selective supplying of the hydraulic pressure from the solenoid valve
Implementation Method 2
a lost motion spring disposed within the first bridge and elastically supporting the plunger
Data Source
AI summary
A variable valve duration/variable valve lift system may include a camshaft, a first cam portion including a first cam, into which the camshaft is inserted and of which a relative phase angle of the first cam with respect to the camshaft is variable, an inner bracket transmitting rotation of the camshaft to the first cam portion, a slider housing into which the inner bracket is rotatably inserted, a first rocker arm having a first end contacting the first cam, a rocker shaft to which the first rocker arm is rotatably connected, a solenoid valve configured to selectively supply hydraulic pressure, a position controller configured to selectively change a position of the slider housing, a first bridge connected to a second end of the first rocker arm and to which a first valve is connected, and a valve lift disposed within the first bridge.