Diaphragm Retainer Ring Cantilever for Sensor Creepage

Solution Overview

Problem

Conventional surgical cassettes for ophthalmic procedures face issues such as insufficient creepage or clearance margins between displacement sensors and diaphragms, misalignment due to inadequate lead-in, and the inability to maintain a robust hermetic seal with the surgical console.

Innovation Solution

The surgical cassette incorporates a diaphragm retainer ring with a cantilever portion that provides increased creepage and clearance margins, acts as a lead-in for displacement sensors, and enhances the robustness of the hermetic seal during ultrasonic welding.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If conventional surgical cassettes are used without a cantilever portion, then the structure is simpler, but the creepage and clearance margins between the displacement sensor and diaphragm are insufficient

Engineering Contradiction:

Improvecreepage and clearance marginVSAvoidstructure complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The diaphragm retainer ring is segmented into distinct functional portions: a base portion for mounting, a cantilever portion extending over the diaphragm, and a flange portion for sealing. This segmentation allows each portion to be optimized for its specific function while maintaining overall structural integrity.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The cantilever portion extends in a radial direction from the base, creating a three-dimensional structure that provides both mechanical support and electrical clearance. This dimensional approach allows the sensor to be positioned close to the diaphragm for measurement while maintaining sufficient creepage and clearance margins through the vertical and radial spacing provided by the cantilever geometry.

Inventive Principle:

Principle #17Another dimension (Dimensionality change)

2Manufacturing precision

If conventional surgical cassettes without adequate lead-in are used, then the assembly is faster, but misalignment between the console and surgical cassette occurs

Engineering Contradiction:

Improvealignment precisionVSAvoidassembly difficulty

Core Design Contradiction:

Manufacturing precisionVSEase of manufacture

Solution Approach 1:

The cantilever portion is pre-formed with a specific geometry that acts as a mechanical guide or lead-in for the displacement sensor. This preliminary structural feature ensures proper alignment is achieved automatically during assembly, eliminating the need for complex alignment procedures or additional adjustment steps.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The cantilever portion serves as an intermediary mechanical element between the base and the displacement sensor. It provides a physical interface that guides the sensor into correct position, mediating the alignment between the console mounting features and the cassette components without requiring direct precision mating between all surfaces.

Inventive Principle:

Principle #24Intermediary (Mediator)

3Strength

If the cantilever portion is not robust enough, then the device is less complex, but cracking or splitting occurs during the welding process

Engineering Contradiction:

Improvewelding robustnessVSAvoidstructural complexity

Core Design Contradiction:

StrengthVSDevice complexity

Solution Approach 1:

The diaphragm retainer ring exhibits local quality variations: the base portion provides rigid mounting, the cantilever portion provides flexible stress distribution, and the flange portion provides sealing. This localized optimization of structural properties allows the cantilever to be robust enough to withstand welding stresses without requiring the entire structure to be overly reinforced.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The diaphragm retainer ring may be formed from composite materials or material combinations that provide both the rigidity needed for welding robustness and the flexibility needed for stress distribution. The integration of different material properties within a single component allows simultaneous achievement of welding strength and crack prevention.

Inventive Principle:

Principle #40Composite materials

4Measurement precision

If insufficient lead-in is provided, then the device is simpler, but misalignment between the displacement sensor and diaphragm occurs

Engineering Contradiction:

Improvesensor alignmentVSAvoidstructural complexity

Core Design Contradiction:

Measurement precisionVSDevice complexity

Solution Approach 1:

The cantilever portion is pre-formed with a specific geometry that acts as a mechanical guide or lead-in for the displacement sensor. This preliminary structural feature ensures proper alignment is achieved automatically during assembly, eliminating the need for complex alignment procedures or additional adjustment steps.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The cantilever portion serves as an intermediary mechanical element between the base and the displacement sensor. It provides a physical interface that guides the sensor into correct position, mediating the alignment between the console mounting features and the cassette components without requiring direct precision mating between all surfaces.

Inventive Principle:

Principle #24Intermediary (Mediator)

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

This configuration ensures accurate alignment and proper sealing between the surgical cassette and the console, while also preventing misalignment and stress concentrations during welding, thereby improving the reliability and performance of ophthalmic surgical procedures.

Implementation Method 1

providing a creepage and clearance margin between a displacement sensor disposed on the surgical console and the diaphragm

Methodology Applied

Scientific EffectCreepage and clearance:

Implementation Method 2

the displacement sensor may induce an eddy current within the top surface of the diaphragm to ascertain its location

Methodology Applied

Scientific EffectEddy current: Eddy Currents

Implementation Method 3

enhances the robustness of the hermetic seal during ultrasonic welding

Methodology Applied

Scientific EffectUltrasonic welding: Ultrasonic Vibration

Data Source

PatentUS20250135088A1Diaphragm retainer ring for ophthalmic surgical cassettes

Publication Date: 2025.05.01 ALCON INC

AI summary

Embodiments disclosed herein provide a surgical cassette including pump assemblies with improved contact between a displacement sensor disposed within a surgical console and a diaphragm disposed within the surgical cassette. Each pump assembly includes a diaphragm retainer ring that provides a sufficient creepage and clearance margin, acts as a lead-in for the displacement sensor, assists in preventing misalignment, and provides robustness for the ultrasonic welding process which couples the diaphragm retainer ring to the surgical console. The diaphragm retainer ring is impregnated with a lubricant so to facilitate seating of the displacement sensor with the cassette. A cantilever portion of the diaphragm retainer ring increases a creepage and clearance margin, as well as increases overall part strength in the event of a collision with the displacement sensor and during ultrasonic welding. An insulator is also provided that further increases the creepage and clearance margin.