Swing-Type SMA Actuator for Automated Locking
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing SMA-based solutions for controlling locks and car fuel lids lack an effective mechanism to block or unblock movable elements, such as in SMA-controlled lock systems, where the use of motors or micromotors is typically required for such functions.
Innovation Solution
A swing-type SMA actuator comprising a stationary frame and a swingable part connected by a pivoting element, with two shape memory alloy wires engaged to connecting elements on the swingable part, allowing for controlled movement and locking of a movable element using Joule heating to disengage a locking mechanism, enabling automatic operation without continuous power application.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Extent of automation
If SMA wires are used to control locks or car fuel lids, then automation and control are improved, but the ability to block/unblock movable elements is insufficient
Solution Approach 1:
The actuator is divided into distinct functional components: a swingable part for movement, a locking element for blocking, and a movable element for actuation. This segmentation allows each component to specialize in its function, with the locking element specifically designed to engage with the movable element to provide reliable blocking capability while the SMA wires provide automated control.
Solution Approach 2:
The locking element acts as an intermediary mechanism between the swingable part and the movable element. It translates the swing motion generated by SMA wire actuation into a reliable blocking action by engaging with the movable element, thereby bridging the gap between automated control and secure blocking capability.
2Reliability
If motors or micromotors are used for blocking/unblocking functions, then reliability is improved, but device complexity and encumbrance increase
Solution Approach 1:
The swingable part serves multiple functions: it acts as a lever arm for the locking element, provides structural support for the SMA wire connections, and enables the blocking action through its swing motion. This multi-functionality eliminates the need for separate motor components, reducing device complexity while maintaining reliable blocking capability.
Solution Approach 2:
The locking element is designed to automatically engage with the movable element through the swing motion of the swingable part, without requiring additional actuators or control systems. The SMA wires directly drive the swingable part, which in turn activates the locking mechanism, creating a self-service system that reduces overall complexity.
3Extent of automation
If SMA wires are engaged to connecting elements on the swingable part, then automation control is improved, but the mechanism for blocking movable elements becomes more complex
Solution Approach 1:
The locking element is merged with the swingable part, forming an integrated assembly where the locking element is positioned on the swingable part and moves with it. This merging reduces the number of separate components and simplifies the overall structure while maintaining the ability to block the movable element through the swing motion.
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 SMA actuator provides reliable and automated control of movable elements, replacing traditional motors in applications like car fuel lid control, offering improved reliability and reduced encumbrance with enhanced stability through bistable positioning and efficient thermal management.
Implementation Method 1
two shape memory alloy wires (14, 14') engaged to two connecting elements (15, 15') present on the swingable part (12) and vertically separated from the pivoting element (13)... The movement of the swingable part 12 is achieved by means of two antagonistic shape memory alloy wires 14, 14' that are alternately actuated via Joule heating.
Implementation Method 2
two shape memory alloy wires (14, 14') engaged to two connecting elements (15, 15') present on the swingable part (12)... The movement of the swingable part 12 is achieved by means of two antagonistic shape memory alloy wires 14, 14' that are alternately actuated via Joule heating.
Data Source
Figure 1A
Figure 1B
Figure 2A~2B
AI summary
The present invention is inherent to a swing-type Shape Memory Alloy (SMA) actuator (10) comprising a stationary frame (11) and a swingable part (12) that are coupled by means of a pivot (13) allowing the swing of the swingable part (12), two SMA wires (14, 14') being engaged to two connecting elements (15, 15') present respectively on a left and right portion of the swingable part (12) and vertically separated from the pivot (13), such that the activation of one of the SMA wires (14, 14') causes the swing of the swingable part (12) in either the clockwise or counter-clockwise direction.