Hydraulic Actuator Pitchlock With Pressure-Differential Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing hydraulic actuator systems face challenges in efficiently controlling the movement of a movable member between two hydraulic chambers, particularly in preventing unwanted movement and maintaining precise control with a simplified valve configuration, which can lead to issues like high pressure peaks and 'blow-by' due to complex valve arrangements and multiple dynamic seals.
Innovation Solution
The actuator system incorporates a resilient biasing member, a stop member, and a movable locking mechanism within the first hydraulic chamber, allowing for controlled pressure management between the chambers to prevent movement towards one chamber while allowing movement towards the other, utilizing a simplified control system with an electro-hydraulic servovalve and valves to operate in multiple modes, including 'coarse', 'fine', 'feather', and 'pitchlock' modes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a complex valve arrangement with multiple dynamic seals is used to control movement between hydraulic chambers, then precise control is achieved, but high pressure peaks and blow-by occur
Solution Approach 1:
The patent extracts and eliminates the complex valve arrangement with multiple dynamic seals from the hydraulic system. Instead, it uses a simplified valve configuration that directly controls pressure differential between chambers without requiring multiple seals, thereby eliminating the source of pressure peaks and blow-by while maintaining control precision
Solution Approach 2:
The patent changes the control parameter from mechanical position control via complex valves to pressure differential control via a simplified valve arrangement. By controlling the pressure differential between the two hydraulic chambers, the system achieves precise movement control without the need for multiple dynamic seals, thus eliminating pressure instability issues
2Device complexity
If a simplified valve configuration is used to reduce complexity, then fewer dynamic seals are needed, but control precision may be compromised
Solution Approach 1:
The patent replaces the complex mechanical valve arrangement with a simplified valve configuration that controls pressure differential. This substitution maintains control precision by focusing on pressure control rather than mechanical position control, achieving the same functional result with fewer components and less complexity
Solution Approach 2:
The patent uses hydraulic pressure differential control to achieve precise movement control. By controlling the pressure difference between two chambers acting on opposite sides of the movable member, the system achieves accurate position control without requiring complex mechanical valve arrangements with multiple dynamic seals
3Reliability
If multiple dynamic seals are used in complex valve arrangements, then control is maintained, but blow-by and pressure leaks occur
Solution Approach 1:
The patent extracts and removes the multiple dynamic seals from the valve arrangement. By eliminating these seals entirely through a simplified valve configuration, the system prevents blow-by and pressure leaks at their source while maintaining control reliability through direct pressure differential control
Solution Approach 2:
The patent converts the potential harm of complex valve arrangements with multiple seals into benefit by using a simplified configuration. The simplification itself becomes the solution, eliminating the seals that cause blow-by and leaks while maintaining or even improving control reliability through more direct pressure control
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 enables efficient, precise control of the movable member in various modes with reduced risk of high pressure peaks and 'blow-by', allowing for fewer dynamic seals and simplified hydraulic control, effectively managing movement and pitch adjustments in propeller systems.
Implementation Method 1
a resilient biasing member arranged for biasing the second wall in a direction towards the first wall
Implementation Method 2
The first chamber may be pressurised by a first fluid and the second chamber may be pressurised by a second fluid, wherein the pressures in the chambers may be controlled so as to move the position of the yoke
Data Source
Figure 1
Figure 2
Figure 3
AI summary
An actuator is disclosed comprising: a moveable member (202); a first hydraulic chamber (204) in contact with a first surface of the moveable member (202); a second hydraulic chamber (206) in contact with a second, opposing surface of the moveable member (202); a movable locking mechanism (210) coupled to a moveable wall (218) of the second hydraulic chamber (206); and a resilient biasing member (214) acting on the moveable wall (218) of the second hydraulic chamber (206) so as to bias the moveable wall and locking mechanism. The actuator is configured to selectively vary the pressure in the second hydraulic chamber (206) so that the resilient biasing member (214) is able to bias the moveable wall (218) to move, thereby moving the locking mechanism (210) to engage the moveable member (202) so as to prevent the movement of the moveable member (202) towards at least one of the first and second hydraulic chambers (204, 206).