Vessel Sealing Instrument Electrode Thermal Management

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing surgical instruments for tissue coagulation and vessel sealing often compromise between simplicity, robustness, and functionality, particularly in disposable and reusable designs, where thermal damage to tissues and inconsistent coagulation results are common issues.

Innovation Solution

A surgical instrument with an electrode unit consisting of a stamped and bent sheet metal part embedded in a plastic body, featuring angled strip sections with openings that reduce heat flow into the plastic, providing thermal and electrical insulation, and a knife guide groove for precise cutting, ensuring uniform coagulation and reduced thermal damage.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Object-affected harmful factors

If the electrode unit uses a solid sheet metal part embedded in plastic body, then thermal insulation is improved, but heat transfer to tissue is reduced

Engineering Contradiction:
Improvethermal damage to tissueVSAvoidheat transfer to tissue
Core Design Contradiction:
Object-affected harmful factorsVSUse of energy by moving object

Solution Approach 1:

The sheet metal part is designed with strip sections that extend into the plastic body, creating a porous-like structure with gaps between the strips. This allows the plastic to provide thermal insulation while maintaining sufficient heat transfer pathways through the strip sections to the tissue contact surface, resolving the contradiction between thermal insulation and heat transfer efficiency

Inventive Principle:
Principle #31Porous materials

Solution Approach 2:

The electrode unit combines sheet metal (conductive, heat-transferring material) with plastic body (insulating material) in a composite structure. The sheet metal part with strip sections embedded in the plastic body creates a composite electrode unit that balances thermal insulation properties of plastic with heat transfer capabilities of metal, addressing both requirements simultaneously

Inventive Principle:
Principle #40Composite materials

2Ease of manufacture

If the instrument is designed for disposable use, then manufacturing cost is reduced, but robustness and reusability are compromised

Engineering Contradiction:
Improvemanufacturing costVSAvoidrobustness
Core Design Contradiction:
Ease of manufactureVSReliability

Solution Approach 1:

The instrument is designed as a disposable device with a plastic body and integrated electrode unit that can be manufactured cost-effectively through injection molding. The sheet metal part is embedded during the molding process, creating a ready-to-use disposable instrument that eliminates the need for expensive sterilization and maintenance infrastructure while maintaining sufficient robustness for single-use applications

Inventive Principle:
Principle #27Cheap short-living objects (Disposable)

Solution Approach 2:

The sheet metal electrode part and plastic body are merged into a single integrated component through embedding during injection molding. This combination simplifies the overall structure, reduces the number of separate parts that need assembly and disassembly, and creates a robust yet cost-effective disposable instrument suitable for single-use scenarios

Inventive Principle:
Principle #5Merging (Combining)

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 design achieves consistent and reproducible coagulation results with minimal thermal damage to tissues, allowing for efficient sealing under various conditions, including difficult access, and maintains instrument safety and handling efficiency.

Implementation Method 1

The heat capacity of the sheet metal part and the thermal conductivity of the plastic body are relatively low. The tissue contact surface can therefore heat up to the desired tissue temperature very dynamically and without significant delay during use

Methodology Applied
Scientific EffectThermal insulation: Thermal Insulation

Implementation Method 2

Another advantage of embedding thin sheet metal parts, intended as electrode or tissue contact surfaces, into the plastic body lies in the thermal and electrical insulation of the sheet metal part from the surrounding tissue

Methodology Applied
Scientific EffectElectrical insulation: Dielectric

Implementation Method 3

The heat capacity of the sheet metal part and the thermal conductivity of the plastic body are relatively low. The tissue contact surface can therefore heat up to the desired tissue temperature very dynamically and without significant delay during use

Methodology Applied
Scientific EffectJoule heating: Joule Heating

Data Source

PatentEP3351198B1Vessel sealing instrument
Publication Date: 2019.08.14 ERBE ELEKTROMEDIZIN GMBH
  • EP3351198B1 patent drawingFigure 1~2
  • EP3351198B1 patent drawingFigure 3~4
  • EP3351198B1 patent drawingFigure 5~10

AI summary

The surgical instrument 10 according to the invention is particularly suitable for vessel sealing. It comprises a tool 15 having at least one branch 16 with an electrode unit 33. This unit consists of a sheet metal part 35, preferably designed as a stamped and bent part, and positively anchored in a plastic body 34, preferably designed as an injection-molded part. The parts extending into the plastic body 34, in particular strip sections 40, 41, have generously dimensioned openings 42, 42a or slots 43, 43a through which the plastic body 34 extends. This achieves not only a positive-locking anchoring of the sheet metal part 35 in the plastic body 34, but also a minimization of heat input into the plastic body 34.The heat capacity of the sheet metal part 35 and the thermal conductivity of the plastic body 34 are low, so that consistently good coagulation results are achieved even after repeated use in short succession, regardless of the initial temperature of the tissue contact surfaces 36.