Tissue Caliper With Magnetic Spring For Consistent Force

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Conventional tissue calipers using mechanical springs face inconsistencies in measurement due to varying force exertion with tissue thickness and viscoelastic properties of tissue, leading to unreliable data collection.

Innovation Solution

A tissue caliper employing a magnetic spring for consistent force over its working range, combined with an ergonomic design and a display assembly that locks measurements after a predetermined time, allowing for accurate and consistent thickness measurements across different tissue types.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Force

If a conventional mechanical spring is used to drive the caliper jaws, then the spring can provide the necessary force to open and close the caliper, but the force varies linearly with extension or compression length, creating measurement inconsistencies for tissue samples of different thicknesses

Engineering Contradiction:

Improvespring force consistencyVSAvoidtissue thickness measurement accuracy

Core Design Contradiction:

ForceVSMeasurement precision

Solution Approach 1:

The patent replaces the conventional mechanical spring with a magnetic spring system that uses magnetic fields instead of mechanical elasticity. The magnetic spring provides a more consistent force output across different compression distances, eliminating the linear force variation problem of mechanical springs and enabling accurate measurements across tissue samples of varying thicknesses.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent changes the fundamental parameter of force generation from mechanical elastic deformation to magnetic field interaction. By using magnetic attraction/repulsion forces that can be maintained at constant strength over a range of distances, the system achieves consistent clamping force regardless of tissue thickness, directly resolving the measurement precision issue.

Inventive Principle:

Principle #35Parameter changes

2Duration of action of moving object

If the caliper applies force to tissue for varied periods of time, then measurements can be taken at different clamping durations, but the viscoelastic properties of tissue cause completely different measurements to be recorded

Engineering Contradiction:

Improveclamping time flexibilityVSAvoidtissue thickness measurement consistency

Core Design Contradiction:

Duration of action of moving objectVSMeasurement precision

Solution Approach 1:

The patent incorporates a measurement locking feature that uses feedback timing to capture the stable measurement value. The system monitors the measurement over time and locks onto the consistent value once the tissue has settled under the constant magnetic spring force, eliminating the variability caused by different clamping durations while maintaining measurement flexibility.

Inventive Principle:

Principle #23Feedback

3Device complexity

If a standard spring is used in the caliper, then the caliper can operate with simple mechanics, but the caliper exerts a much greater force on thicker samples (1-inch) than on thinner samples (0.10-inch), creating measurement variability

Engineering Contradiction:

Improvespring mechanism simplicityVSAvoidmeasurement consistency across different tissue thicknesses

Core Design Contradiction:

Device complexityVSReliability

Solution Approach 1:

The patent replaces the simple mechanical spring with a magnetic spring system that maintains consistent force output. While this increases device complexity slightly, it dramatically improves reliability by ensuring that the same clamping force is applied regardless of whether the tissue sample is 0.10-inch or 1-inch thick, eliminating the measurement variability inherent in mechanical spring systems.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

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 magnetic spring provides consistent force across varying tissue thicknesses, while the ergonomic design and locking feature enhance measurement reliability and reduce variability, resulting in more accurate and user-friendly data collection.

Implementation Method 1

The activation assembly includes a magnetic spring for effecting the opening and closing of the caliper assembly. The magnetic spring may be operably connected to the sliding member.

Methodology Applied

Scientific EffectMagnetic spring: Magnetism

Implementation Method 2

The switch assembly may include a switch and an RC control circuit. The RC control circuit may be configured to lock the displayed measurement a predetermined time after the release of the switch.

Methodology Applied

Scientific EffectRC control circuit: Capacitance

Data Source

PatentUS9541367B2Tissue caliper

Publication Date: 2017.01.10 COVIDIEN LP

AI summary

A tissue caliper is provided. The tissue caliper includes a housing assembly including a tubular body, an activation assembly operably received within the housing assembly, and a caliper assembly operably connected to the activation assembly. The activation assembly includes a magnetic spring for effecting the opening and closing of the caliper assembly. Also provided is a kit for measuring tissue thickness.