Mechanical Landing Gear Uplock via Cam Plate and Hook
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional aircraft uplock mechanisms are complex and heavy due to their reliance on hydraulic systems, which complicates their design and functionality, necessitating a more lightweight and simpler solution for locking landing gear in a stowed position during flight.
Innovation Solution
A mechanically operated uplock system utilizing a cam plate, hook, follower, and biasing members to securely lock and unlock the landing gear, featuring a cam channel, stopper, and manual release system, which reduces weight and part count by eliminating hydraulic actuation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If hydraulic actuation systems are used for uplock mechanisms, then the landing gear can be reliably locked in stowed position, but the system becomes complex and heavy
Solution Approach 1:
The patent extracts and eliminates the hydraulic actuation system from the uplock mechanism, replacing it with a purely mechanical system. The follower member is directly actuated by landing gear movement through cam surfaces, removing the need for hydraulic actuators while maintaining the locking function. This extraction resolves the contradiction by eliminating the source of complexity and weight without compromising reliability.
Solution Approach 2:
The uplock mechanism is designed to be self-actuating through the movement of the landing gear itself. The follower member follows cam surfaces that are directly driven by landing gear position changes, causing automatic engagement and disengagement of the locking mechanism without requiring external hydraulic power. This self-service approach eliminates complex control systems while maintaining reliable operation.
2Reliability
If hydraulic actuation systems are used for uplock mechanisms, then the landing gear can be locked in stowed position, but the system weight increases
Solution Approach 1:
The patent removes the hydraulic actuation system entirely from the uplock mechanism, eliminating the weight of hydraulic actuators, fluid lines, and associated components. The mechanical follower-cam-stopper system uses only structural components and springs, dramatically reducing the weight of the moving parts while maintaining the locking function through direct mechanical coupling to landing gear movement.
Solution Approach 2:
The mechanism uses the kinetic energy and movement of the landing gear itself to actuate the locking mechanism through the follower and cam surfaces, eliminating the need for heavy hydraulic power systems. Only light spring components are needed to provide biasing forces, rather than heavy hydraulic actuators, resulting in significant weight reduction while maintaining reliable locking.
3Device complexity
If conventional spring loaded catch systems are used, then the uplock mechanism is simpler, but it cannot withstand significant forces during flight
Solution Approach 1:
The patent uses cam surfaces with specific curved geometries to provide mechanical advantage and force multiplication. The cam profiles are designed to convert the relatively small movement of the follower into large locking forces at the stopper and latch points. This curved surface geometry allows the simple mechanical system to generate the high forces needed to secure the landing gear during flight without adding hydraulic complexity.
Solution Approach 2:
The mechanism is designed to be dynamically loaded during the locking process, where the follower's movement through the cam surfaces creates progressive engagement of the stopper and latch members. The system utilizes the dynamic movement and inertia of the landing gear to generate the necessary locking forces, rather than relying solely on static spring forces, thereby achieving high strength with a simple mechanical design.
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
The system provides a lightweight, passive, and self-operated mechanism that effectively secures the landing gear in a stowed position while allowing for efficient deployment, capable of withstanding significant forces and designed for reliability and simplicity.
Implementation Method 1
a first biasing member configured to bias the stopper in a first rotational direction relative to the cam plate
Implementation Method 2
a follower rotatably coupled to the hook, wherein a portion of the follower moves within the cam channel
Implementation Method 3
The first biasing member comprises a compression spring
Implementation Method 4
the second biasing member comprises a tension spring
Data Source
AI summary
An uplock system includes a cam plate comprising a cam channel, a hook configured to rotate with respect to the cam plate, a follower rotatably coupled to the hook, wherein a portion of the follower moves within the cam channel in response to rotation of the hook, a stopper configured to engage the follower, and a first biasing member configured to bias the stopper towards the follower to stop the follower from moving within the cam channel, thereby locking the hook in a locked position.