Indentation Testing Instrument Frame Compliance Correction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing indentation testing instruments face errors in machine frame compliance correction due to presuming methods, leading to inaccurate measurements of material hardness, and require multiple displacement gauges for precise measurement.
Innovation Solution
The instrument employs a loading lever and a reference lever with displacement sensors to measure indentation depths, allowing for the calculation of machine frame compliance and correction of indentation depth measurements using a correlation function between load and compliance, thereby eliminating errors and improving precision.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If a correction method based on presuming machine frame compliance is used (as in ISO14577), then the measurement process is simplified, but measurement precision deteriorates due to errors in the presuming method
Solution Approach 1:
The patent replaces the presumptive calculation method with direct physical measurement using a displacement gauge. The machine frame compliance is measured by detecting the actual displacement of the indenter when applied to a rigid reference surface, substituting theoretical computation with empirical measurement to eliminate presumption errors.
Solution Approach 2:
The system uses the indentation testing instrument's own displacement gauge to measure its machine frame compliance, allowing the instrument to self-characterize its compliance without requiring external equipment or presumptive calculations based on specimen test results.
2Measurement precision
If multiple displacement gauges are used to measure both machine frame distortion and indenter indentation depth, then measurement precision is improved, but device complexity increases
Solution Approach 1:
The patent makes a single displacement gauge multi-functional by enabling it to measure both machine frame compliance and indenter indentation depth through different measurement modes. The gauge measures displacement relative to the machine frame for compliance characterization and relative to the specimen for indentation depth, eliminating the need for separate measurement devices.
Solution Approach 2:
The patent combines the functions of measuring machine frame distortion and indenter indentation depth into a single displacement gauge measurement system. By measuring the position of the indenter relative to the machine frame and calculating compliance from this single measurement, the patent merges what would traditionally require multiple gauges into one integrated measurement approach.
Data Source
AI summary
An indentation testing instrument including: a loading lever supported pivotally; an indenter provided on the loading lever; a displacement sensor movable section; a loading lever driving section; a reference lever supported pivotally having a same shaft center as the loading lever; a contactor provided on the reference lever as a positional reference of a tip portion of the indenter; a displacement sensor fixing section; a reference lever driving section; a stopper to stop the reference lever; a specimen surface reference measurement member to turn the loading lever from a state that the contactor touches the specimen surface, and to measure a first indentation depth amount; and a machine frame reference measurement member to turn the loading lever from a state that the reference lever touches the stopper and the contactor is spaced apart from the specimen surface, and to measure a second indentation depth amount.