Laser Triangulation Density Measurement for Extreme Temperatures

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing devices for measuring bulk and tapped density of powders are limited by temperature sensitivity, particularly inductive sensors which lose accuracy at high temperatures and provide poor resolution when measuring at extreme temperatures.

Innovation Solution

A device using a laser distance measuring system positioned at a sufficient distance from the powder bed to minimize temperature influence, employing downward-oriented laser triangulation for accurate distance measurement over a broad temperature range (-80°C to 300°C), with a temperature adjusting mechanism to maintain optimal sensor conditions.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If an inductive sensor is used to measure the distance between the reference point and the powder bed, then the measurement accuracy is improved at ambient temperature, but the measurement accuracy deteriorates at high temperatures

Engineering Contradiction:
Improvedistance measurement accuracyVSAvoidoperating temperature range
Core Design Contradiction:
Measurement precisionVSTemperature

Solution Approach 1:

The patent replaces the inductive sensor (electromagnetic field-based) with a laser distance measuring device that uses optical triangulation. This substitution eliminates temperature sensitivity issues because optical measurements are not affected by thermal interference in the same way electromagnetic sensors are. The laser device measures distance by triangulating the position of a laser spot on the powder bed surface, providing accurate measurements across a broad temperature range from -80°C to 300°C.

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

Solution Approach 2:

The patent introduces a reflector as an intermediary element placed on the powder bed surface. The laser beam reflects off this reflector back to the sensor, enabling indirect measurement. This intermediary allows the sensor to be positioned at a distance from the powder bed while maintaining measurement accuracy, and the reflector serves as a stable reference point that is not affected by temperature changes.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Measurement precision

If the distance between the sensor and the powder bed is kept short to maintain measurement accuracy, then the measurement resolution is improved, but the sensor becomes too exposed to temperature and suffers damage

Engineering Contradiction:
Improvedistance measurement resolutionVSAvoidtemperature exposure to sensor
Core Design Contradiction:
Measurement precisionVSObject-affected harmful factors

Solution Approach 1:

The reflector acts as an intermediary that enables the sensor to be positioned farther from the powder bed. The laser beam travels to the reflector and back, effectively doubling the optical path length while allowing physical separation between the sensor and the hot/cold environment. This resolves the contradiction by decoupling measurement resolution from sensor proximity to the measured object.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent changes the measurement geometry from a direct vertical measurement to an angled triangulation measurement. By measuring at an angle and using trigonometric relationships, the system achieves high resolution measurements over longer distances. The laser spot position on the reflector is measured, and the distance is calculated using triangulation principles, effectively using a different dimensional approach to the measurement problem.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

3Measurement precision

If a cover element with metallic layer is placed on the powder sample, then the measurement accuracy is improved, but the device complexity increases

Engineering Contradiction:
Improvedistance measurement accuracyVSAvoidapparatus structure
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent extracts the requirement for a metallic cover element by replacing inductive sensing with optical laser triangulation. The laser method does not require the powder bed to have specific electromagnetic properties, eliminating the need for artificial metallic layers. This simplifies the overall device structure while maintaining or improving measurement accuracy.

Inventive Principle:
Principle #2Taking out (Extraction)

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 device achieves high accuracy and resolution in measuring bulk and tapped density across a wide temperature range, reducing the impact of temperature on measurement accuracy and extending the operational range of the device.

Implementation Method 1

employing downward-oriented laser triangulation for accurate distance measurement over a broad temperature range (-80°C to 300°C)

Methodology Applied
Scientific EffectLaser triangulation: LIDAR

Implementation Method 2

with a temperature adjusting mechanism to maintain optimal sensor conditions

Methodology Applied
Scientific EffectTemperature control: Heating

Data Source

PatentEP3924715B1Device and method for measuring bulk and/or tapped density, as well as packing dynamics
Publication Date: 2024.07.24 GRANUTOOLS
  • EP3924715B1 patent drawingFigure 1~2
  • EP3924715B1 patent drawingFigure 3~4B
  • EP3924715B1 patent drawingFigure 5~7

AI summary

Device and method for measuring bulk and/or tapped density as well as packing dynamics comprising a driving mechanism (31), a vessel (5) with temperature adjusting means (7) for containing a powder sample having a predetermined mass, said vessel (5) being provided to move up and down upon the operation of said driving mechanism (31), and a laser distance measuring device.