Hydraulic Indenter Apparatus for Precision Metal Testing

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing indentation apparatus for detecting mechanical features of metal materials face challenges with high inertia, mechanical wear, structural complexity, and bulkiness due to mechanical force amplification, which affects precision and centering accuracy.

Innovation Solution

The apparatus employs a hydraulic force amplification system using bellows and position sensors arranged at 120° around the indenter to reduce fluid leakage and linear deformation, enabling precise measurements with reduced mechanical wear and size, and utilizes a rotating element with a translating mechanism for generating controlled force.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If mechanical amplification is used to control indenter stroke, then measurement precision is improved, but device complexity and mechanical wear increase

Engineering Contradiction:
Improveindenter stroke measurement precisionVSAvoidmechanical amplification structure complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent replaces the traditional mechanical amplification system with a hydraulic amplification system. The hydraulic system uses fluid pressure transmission to achieve force and motion amplification without complex mechanical linkages, thereby reducing mechanical wear and structural complexity while maintaining measurement precision through controlled fluid displacement.

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

Solution Approach 2:

The patent employs a hydraulic actuator with a piston and cylinder arrangement to amplify the indenter stroke. The hydraulic system transmits force through incompressible fluid, providing smooth and precise control of the indenter penetration depth without the inertia and wear associated with mechanical gear systems.

Inventive Principle:
Principle #29Pneumatics and hydraulics

2Measurement precision

If mechanical amplification is used to control indenter stroke, then measurement precision is improved, but inertia increases

Engineering Contradiction:
Improveindenter stroke control precisionVSAvoidsystem inertia
Core Design Contradiction:
Measurement precisionVSWeight of moving object

Solution Approach 1:

The patent substitutes the heavy mechanical amplification mechanism with a hydraulic system that has significantly lower moving mass. The hydraulic fluid transmits force without the inertia of gears, shafts, and linkages, enabling faster response times and reduced oscillations during indentation testing.

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

3Measurement precision

If high structural stiffness with guides is used to ensure centering precision, then centering accuracy is improved, but device complexity and encumbrance increase

Engineering Contradiction:
Improveindenter centering precisionVSAvoidstructural complexity with guides
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent removes the complex guide structures from the indenter assembly by relying on the inherent stiffness of the hydraulic actuator and the rigid mounting structure. The indenter is directly coupled to the hydraulic piston, eliminating the need for separate guiding mechanisms while maintaining centering precision through proper alignment of the hydraulic system.

Inventive Principle:
Principle #2Taking out (Extraction)

4Force

If traditional hydraulic actuators with sliding pistons are used, then force amplification is achieved, but fluid leakage occurs

Engineering Contradiction:
Improvehydraulic force amplificationVSAvoidfluid transmission reliability
Core Design Contradiction:
ForceVSReliability

Solution Approach 1:

The patent employs flexible bellows instead of rigid sliding pistons for hydraulic actuation. The bellows expand and contract to accommodate volume changes in the hydraulic fluid while maintaining sealed containment, thereby preventing leakage while still achieving the necessary force amplification through hydraulic pressure.

Inventive Principle:
Principle #30Flexible shells and thin films

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 solution provides a lightweight, compact, and precise apparatus for detecting mechanical features of metal materials, reducing mechanical wear and enhancing measurement accuracy by independent rotation correction and hydraulic force amplification.

Implementation Method 1

a second hydraulic actuator, in hydraulic connection with the first actuator, the second hydraulic actuator having a cross section larger than the first actuator and being operatively connected to the indenter to which it transmits the amplified force

Methodology Applied
Scientific EffectHydraulic amplification: Pascal's Law

Implementation Method 2

at least one among the first and the second hydraulic actuator is a bellows. This way, it is possible to reduce the loss of fluid of transmission that would leak if the hydraulic actuator were a piston slidingly mounted in a cylinder

Methodology Applied
Scientific EffectFlexible sealing:

Implementation Method 3

The arrangement of the position sensor near the indenter allows reducing possible linear deformation to which the apparatus is subject while detecting the data. According to the invention, the means for measuring the depth of penetration h of the indenter in the sample provides three position sensors that are not aligned and are arranged near the indenter same

Methodology Applied
Scientific EffectPosition sensing:

Data Source

PatentEP1946069B1Apparatus for detecting mechanical features of materials
Publication Date: 2017.08.02 S M SCIENZIA MACHINALE
  • EP1946069B1 patent drawingFigure 1~3
  • EP1946069B1 patent drawingFigure 4~5
  • EP1946069B1 patent drawingFigure 6~7

AI summary

An apparatus (1) for detecting mechanical features of materials, in particular metal materials, comprising an indenter (10) adapted to be pushed against a sample material (15) in which it penetrates for a depth (h) and responsive to the hardness of the materials same. The apparatus (1) provides means for generating a measured force (F) and a transmission gear (35) which changes the rotational motion of shaft (40) of motor (30) into a linear reversible movement. The force generated is then amplified in a hydraulic way and transmitted to thr indenter (10) . This solution allows to lighten and to reduce the size of the mechanisms for generating the force, reducing also wear and mechanical backlash, as well as costs and overall dimensions. An advantage is also to measure with precision the stroke of the indenter with corresponding control in precision of the penetration (h) of the indenter in the sample material.