Shape Memory Injector for Intraocular Lens Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current injector arrangements for intraocular lenses have complex drive units, which can lead to uneven advancement of the plunger, and existing solutions do not provide a simple structure for controlling the speed of the plunger during lens insertion, potentially causing the lens to be pushed out uncontrolled.
Innovation Solution
An injector arrangement with a drive unit featuring a shape memory material actuator, such as Nitinol, and a heating device, which uses electrical resistance measurement to control the actuator's length and speed, ensuring controlled and precise insertion of the intraocular lens, and an energy source for heating the lens to make it more flexible.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a motor-driven drive unit is used to move the plunger, then the plunger advancement can be controlled, but the device complexity increases
Solution Approach 1:
The patent replaces the motor-driven mechanical system with a shape memory alloy-based thermal actuation system. The plunger is moved by heating the shape memory alloy actuator, which changes its physical properties and drives the plunger through thermal expansion rather than mechanical motor rotation, thereby simplifying the drive unit structure while maintaining controlled advancement
Solution Approach 2:
The patent changes the physical parameter of the actuator material from a motor-driven mechanical system to a shape memory alloy that responds to temperature changes. By controlling the temperature of the actuator through electrical heating, the plunger advancement is controlled without requiring a complex motor-driven mechanism
2Device complexity
If manual pressing of the plunger is used, then the device structure is simple, but the plunger advancement becomes uneven
Solution Approach 1:
The patent replaces manual mechanical pressing with an electrically-heated shape memory alloy actuator system. This substitution provides controlled, uniform thermal expansion that drives the plunger at a consistent rate, eliminating the uneven advancement caused by manual pressing while keeping the device structure relatively simple
Solution Approach 2:
The patent incorporates a control unit that monitors and regulates the heating of the shape memory alloy actuator. This feedback control ensures that the actuator temperature is maintained within optimal parameters, resulting in uniform and controlled plunger advancement throughout the injection process
3Productivity
If the plunger speed is high during lens insertion, then the insertion process is faster, but the lens may be ejected uncontrolled
Solution Approach 1:
The patent employs dynamic control of the plunger speed by adjusting the heating rate of the shape memory alloy actuator throughout the injection process. The control unit modulates the heating power to accelerate the plunger initially for faster insertion, then gradually reduces the heating rate near the end to slow down the plunger movement, ensuring the lens is deposited controlledly without uncontrolled ejection
Solution Approach 2:
The patent uses periodic or staged heating cycles of the shape memory alloy actuator. The heating is applied in controlled stages: initial rapid heating for fast plunger movement and lens insertion, followed by reduced or stopped heating as the lens approaches the target position, creating a speed-profiled insertion process that maintains 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
The solution provides a simple and controlled mechanism for inserting intraocular lenses, ensuring precise and controlled advancement of the plunger, preventing uncontrolled ejection of the lens and making the process more efficient.
Implementation Method 1
an actuator (2) having a shape memory material with a transition temperature, a first longitudinal end (8) and a second longitudinal end (9)... when the actuator (2) is heated to a temperature above the transition temperature, it changes its length
Implementation Method 2
a heating device (18) which is configured to heat the actuator (2) to a temperature above the transition temperature
Implementation Method 3
the resistance measuring device is preferably configured to measure the electrical resistance from the first longitudinal end to the second longitudinal end
Data Source
Figure 1~2
Figure 3~4
AI summary
The invention relates to an injector arrangement (1) having an actuator (2), which has a shape-memory material with a transition temperature, a first longitudinal end (8) and a second longitudinal end (9), having a support seat (6) on which the actuator (2) is supported in the region of the first longitudinal end (8), having a plunger (3) which is mounted longitudinally displaceably in the injector arrangement (1), wherein the plunger (3) is configured, through its longitudinal displacement, to displace an intraocular lens (16) and is secured on the second longitudinal end (9), and having a heating device which is configured to heat the actuator (2) to a temperature above the transition temperature, as a result of which the actuator (2) changes its length, and the plunger (3) is thus longitudinally displaced.