Actuator Locking Pin Mechanism for Hydraulic Failure Failsafe
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Solution Overview
Problem
Existing locking mechanisms for actuators are expensive, complex, and prone to failure due to their reliance on hydraulic systems, which are costly to manufacture and maintain, and often require frequent maintenance or replacement.
Innovation Solution
A locking hydraulic actuator mechanism featuring a piston-style locking pin that uses a mechanical bias, such as a spring, to lock the actuator in place, allowing for reliable locking in both extended and retracted positions, even in the event of hydraulic pressure loss, with a simplified design that reduces the number of components and manufacturing costs.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a hydraulic control system is used for the locking mechanism, then the actuator can be locked in position, but the system becomes expensive to manufacture and maintain
Solution Approach 1:
The patent extracts the locking function from the complex hydraulic control system and implements it through a separate, simpler mechanical locking mechanism with a locking pin that engages with a locking surface on the piston rod. This mechanical locking system operates independently from the hydraulic actuation system, eliminating the need for complex hydraulic control components while maintaining reliable locking capability.
Solution Approach 2:
The patent replaces the hydraulic control system with a mechanical locking system. Instead of using hydraulic pressure control to maintain the locked state, the invention uses a mechanical locking pin that physically engages with the piston rod. This substitution eliminates hydraulic valves, seals, and control circuits, significantly reducing system complexity and maintenance requirements.
2Reliability
If present locking mechanisms are used, then the actuator can be locked, but the mechanisms have numerous parts and are susceptible to breakage and wear
Solution Approach 1:
The locking mechanism is segmented into distinct functional components: a locking pin mounted on the actuator housing and a corresponding locking surface on the piston rod. This segmentation allows each component to be optimized for its specific function and manufactured using appropriate processes, reducing overall complexity and manufacturing cost while maintaining reliability.
Solution Approach 2:
The locking pin and locking surface are designed as simple, robust mechanical components that can be manufactured at low cost using standard machining processes. The design accepts that these components may wear over time and can be easily replaced, rather than designing for indefinite life. This approach significantly reduces manufacturing cost while maintaining adequate reliability for the application.
3Reliability
If present locking mechanisms are used, then the actuator can be locked in position, but regular maintenance or replacement is required at high cost
Solution Approach 1:
The locking mechanism is designed to be self-servicing in normal operation, with the locking pin automatically engaging the locking surface when the piston rod reaches its retracted position. The mechanical design ensures that the locking function is maintained without requiring external control systems or regular maintenance intervention, significantly reducing maintenance costs and complexity.
Solution Approach 2:
The locking function is extracted as a separate mechanical subsystem that operates independently from the hydraulic actuation system. This extraction allows the locking mechanism to be maintained, repaired, or replaced without affecting the hydraulic system, and vice versa. The simplified mechanical design requires minimal maintenance compared to integrated hydraulic locking systems.
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 solution provides a cost-effective, reliable, and low-maintenance locking mechanism that can lock actuators in specific positions with minimal parts, ensuring robustness and reliability, and acts as a failsafe in case of hydraulic failure, reducing maintenance and overhaul costs.
Implementation Method 1
the locking pin can be mechanically biased towards the locking position by a spring
Implementation Method 2
the lower interior actuator chamber is in fluid communication with the lower chamber of the interior cavity such that hydraulic fluid received in the lower interior actuator chamber exerts an unlocking force on the locking pin to move the locking pin towards the unlocked position
Implementation Method 3
the upper interior actuator chamber is in fluid communication with the upper chamber of the interior cavity such that hydraulic fluid received in the upper interior actuator chamber exerts a locking force on the locking pin to move the locking pin to the locked position
Data Source
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AI summary
A locking mechanism for locking an actuator piston within an actuator cylinder housing is disclosed. The locking mechanism comprises a locking pin that is moveable between extended and retracted positions. The locking pin can be moved using a controller, such as a hydraulic controller, for example. In the extended position the locking pin engages the actuator piston thereby locking the actuator piston in a specific position. The locking mechanism includes a mechanical bias (such as a spring or other mechanical system) that biases the locking pin towards an extended position to lock the actuator piston when counter-pressure on the locking pin is lower than the pressure provided by the mechanical bias. The locking pin can be hydraulically operated so that hydraulic pressure that forces the actuator piston to retract also exerts force on the locking pin to move it from a locked position to an unlocked position.