Electromechanical Actuator Jammed State Recovery
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional electromechanical actuators with screw mechanisms can become jammed, leading to failure in driving systems, especially when electric motors stop or experience malfunctions, resulting in inability to advance or retract the output portion with respect to the housing.
Innovation Solution
An electromechanical actuator design incorporating a sliding support mechanism and a piston portion that uses fluid pressure to maintain the drive portion's position, allowing the driven portion to advance and withdraw even if a jammed state occurs, utilizing both electric power and fluid pressure as driving sources.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If a screw mechanism is used to convert rotational driving force to linear driving force, then the actuator can output linear driving force, but a jammed state may occur in the screw mechanism due to prying or seizure
Solution Approach 1:
A piston portion is introduced as an intermediary between the electric motor and the screw mechanism. The piston can move linearly within the housing and is connected to the drive portion through a sliding support mechanism, allowing it to mediate the transmission of force while maintaining the ability to extract and reset the jammed screw mechanism.
Solution Approach 2:
The actuator is divided into functionally independent segments: the electric motor, the piston portion, the sliding support mechanism, and the screw mechanism. This segmentation allows the screw mechanism to be extracted and replaced independently when jammed, while the piston and motor remain functional.
2Ease of operation
If the electric motor stops due to jammed state or malfunction, then the actuator becomes unable to be driven
Solution Approach 1:
The piston portion serves as a mediator that can operate independently of the electric motor. When the motor stops, the piston can still be manually moved to advance or retract the output portion, ensuring the actuator remains operable.
Solution Approach 2:
The sliding support mechanism allows the piston to move freely within the housing without requiring motor activation. The piston can be manually positioned and the screw mechanism can be manually advanced or retracted, enabling the system to service itself in emergency situations.
3Reliability
If a piston portion is added to control drive portion position using fluid pressure, then the drive portion position can be maintained, but the device complexity increases
Solution Approach 1:
The piston portion serves multiple functions: it maintains the drive portion position through fluid pressure, allows manual operation when the motor fails, and provides a means to extract and reset the screw mechanism. This multi-functionality justifies the added complexity.
Solution Approach 2:
Fluid pressure is used to control the piston position and maintain the drive portion at a predetermined position. This hydraulic/pneumatic system provides precise control while maintaining simplicity in the control mechanism.
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
Enables continuous operation of the actuator by maintaining the drive portion's position and allowing controlled movement of the driven portion, even in jammed states or motor stoppages, ensuring reliable operation of connected equipment.
Implementation Method 1
the piston portion being controlled so as to be at a predetermined position in the advancing and withdrawing direction with respect to the housing by means of pressure of a fluid supplied to and discharged from the housing
Implementation Method 2
a sliding support mechanism that transmits rotational force of the electric motor to the drive portion and allows the drive portion to slide in the advancing and withdrawing direction with respect to the electric motor
Data Source
AI summary
An actuator is driven even if a jammed state, a motor stop, or the like occurs. An electromechanical actuator includes: an electric motor attached to a housing; a conversion mechanism portion having a drive portion that is driven to rotate by the electric motor and a driven portion that is driven by the drive portion and advances and withdraws in a predetermined advancing and withdrawing direction, the conversion mechanism portion being accommodated in the housing; a sliding support mechanism that transmits rotational force of the electric motor to the drive portion and allows the drive portion to slide in the advancing and withdrawing direction with respect to the electric motor; and a piston portion controlled so as to be at a predetermined position in the advancing and withdrawing direction with respect to the housing by means of pressure of a fluid supplied to and discharged from the housing.