US 12,007,373 B2
Liquid chromatograph
Tomohiro Gomi, Kyoto (JP); and Daisuke Kitabayashi, Kyoto (JP)
Assigned to SHIMADZU CORPORATION, Kyoto (JP)
Appl. No. 17/438,419
Filed by SHIMADZU CORPORATION, Kyoto (JP)
PCT Filed Mar. 13, 2019, PCT No. PCT/JP2019/010420
§ 371(c)(1), (2) Date Sep. 11, 2021,
PCT Pub. No. WO2020/183684, PCT Pub. Date Sep. 17, 2020.
Prior Publication US 2022/0146474 A1, May 12, 2022
Int. Cl. G01N 30/20 (2006.01); G01N 30/32 (2006.01); G01N 30/86 (2006.01); G01N 30/02 (2006.01)
CPC G01N 30/8675 (2013.01) [G01N 30/32 (2013.01); G01N 2030/027 (2013.01)] 7 Claims
OG exemplary drawing
 
1. A liquid chromatograph comprising:
a liquid sending system having an analysis flow path and including:
a liquid sending pump for sending a mobile phase through the analysis flow path;
a sample injector that injects a sample into the mobile phase flowing through the analysis flow path;
a separation column provided on the analysis flow path and configured to separate the injected sample into components; and
a pressure sensor for detecting a liquid sending pressure in the analysis flow path, wherein the pressure sensor is located at a position farther upstream along the analysis flow path than the separation column;
computer circuitry configured to:
hold in memory a capacity value representing an internal capacity of the liquid sending system;
determine a reference fluctuation range of the liquid sending pressure based on the capacity value; and
periodically acquire liquid sending pressures detected by the pressure sensor;
obtain a fluctuation range of the liquid sending pressure in a certain during a driving period of the liquid sending pump; and
detect a liquid sending failure based on the obtained fluctuation range and the reference fluctuation range.