US 11,852,614 B2
Material testing machine and method of controlling material testing machine
Tohru Matsuura, Kyoto (JP)
Assigned to SHIMADZU CORPORATION, Kyoto (JP)
Appl. No. 17/297,455
Filed by SHIMADZU CORPORATION, Kyoto (JP)
PCT Filed Jun. 10, 2019, PCT No. PCT/JP2019/022931
§ 371(c)(1), (2) Date May 26, 2021,
PCT Pub. No. WO2020/110354, PCT Pub. Date Jun. 4, 2020.
Claims priority of application No. 2018-221910 (JP), filed on Nov. 28, 2018.
Prior Publication US 2022/0034775 A1, Feb. 3, 2022
Int. Cl. G01N 3/30 (2006.01); G01N 3/08 (2006.01); G05B 5/01 (2006.01); G05B 13/02 (2006.01)
CPC G01N 3/08 (2013.01) [G01N 3/30 (2013.01); G05B 5/01 (2013.01); G05B 13/0205 (2013.01); G01N 2203/0017 (2013.01); G01N 2203/0218 (2013.01)] 11 Claims
OG exemplary drawing
 
1. A material testing machine comprising:
a load mechanism that applies a load to a test object;
a load measurement device that measures the load applied to the test object; and
a control device that performs a feedback control for the load mechanism based on a deviation between a measurement value of the load and a target value of the load,
wherein a change in a physical quantity generated in the test object due to the load is measured, and
the control device comprises a hunting detection unit that detects hunting by comparing a frequency spectrum obtained by converting time-series data of the measurement value with a frequency spectrum obtained by converting time-series data of the target value, or by comparing a frequency spectrum obtained by converting time-series data of a command value of the feedback control with the frequency spectrum obtained by converting the time-series data of the target value.