Induction Shrink Holder Heating Control via Coil Inductance

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing shrinking devices for tool holders lack optimal automation, leading to overheating issues and structural damage due to inaccurate temperature measurement methods, which are prone to errors from surface color, texture, and contamination.

Innovation Solution

A method and device that measure the instantaneous inductance of the induction coil during heating, switching off the power supply when a predetermined value is reached, and utilize a compact design with shielding to reduce stray fields and improve temperature control, allowing precise heating and cooling of the tool holder sleeve section.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If temperature measurement is performed using infrared detector or touch-sensitive sensor, then temperature monitoring is enabled, but measurement accuracy deteriorates due to surface color, texture, and contamination

Engineering Contradiction:
Improvetemperature measurement accuracyVSAvoidsurface color, texture, and contamination influence
Core Design Contradiction:
Measurement precisionVSObject-affected harmful factors

Solution Approach 1:

The patent introduces an intermediary measurement approach by measuring the inductance of the induction coil instead of directly measuring the temperature of the cartridge case. The inductance change serves as a mediator that correlates with temperature rise without being affected by surface properties. This indirect measurement method eliminates the harmful effects of surface color, texture, and contamination on measurement accuracy.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent replaces the mechanical/optical measurement systems (infrared detectors and touch-sensitive sensors) with an electrical measurement system. By measuring the electrical inductance of the induction coil, which changes with temperature, the system avoids the limitations of optical and mechanical contact methods. This substitution of measurement principle fundamentally resolves the accuracy problems caused by surface conditions.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

2Temperature

If inductive heating is applied for extended duration to ensure adequate heating, then heating effectiveness is improved, but overheating and structural damage occur

Engineering Contradiction:
Improveheating effectivenessVSAvoidstructural integrity of cartridge case
Core Design Contradiction:
TemperatureVSReliability

Solution Approach 1:

The patent implements a feedback control system where the inductance of the induction coil is continuously monitored during heating. Since inductance changes with temperature, this provides real-time feedback on the thermal state of the cartridge case. The system can automatically adjust or terminate heating when the desired temperature is reached, preventing overheating and structural damage while ensuring adequate heating effectiveness.

Inventive Principle:
Principle #23Feedback

Solution Approach 2:

The patent introduces dynamic control of the heating process by continuously monitoring inductance changes and adjusting heating parameters accordingly. Instead of fixed-duration heating, the system adapts the heating process based on real-time inductance measurements, allowing optimal heating effectiveness while preventing excessive temperature rise that would compromise structural integrity.

Inventive Principle:
Principle #15Dynamics

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 approach ensures accurate temperature control, preventing overheating and structural damage, while enabling a compact, mobile shrinking device that can be safely and efficiently used on-site for tool changes.

Implementation Method 1

inductive heating of the sleeve section of a tool holder

Methodology Applied
Scientific EffectInductive heating: Induction Heating

Implementation Method 2

heated the sleeve portion of the tool holder to expand it

Methodology Applied
Scientific EffectThermal expansion: Thermal Expansion

Implementation Method 3

induction coil... supplied with an alternating current... for heating the sleeve section

Methodology Applied
Scientific EffectElectromagnetic induction: Electromagnetic Induction

Data Source

PatentEP3691409B1Shrinking apparatus with heating control
Publication Date: 2023.07.26 HAIMER
  • EP3691409B1 patent drawingFigure 1
  • EP3691409B1 patent drawingFigure 2
  • EP3691409B1 patent drawingFigure 3~4

AI summary

Method for monitoring the temperature of the sleeve portion of a tool holder inserted into the induction coil of a shrink device, wherein the instantaneous inductance of the induction coil is measured during inductive heating and the current supply to the induction coil is influenced when the instantaneous inductance approaches, reaches or exceeds a predetermined value.