Shimadzu Corporation

Daisuke Kitabayashi

Tomohiro Gomi

Shinya Imamura

Keisuke Ogawa

Masahide Gunji

Yusuke Yokoi

Masataka Nikko

Kota Kamei

A liquid chromatograph () includes a liquid-sending unit () for sending a mobile phase from a reservoir () to a column () through a tube () at a predetermined pressure. The unit () includes a pump () having a suction port () connected to the reservoir and an ejection port () connected to the tube directly or via another pump. A check valve () is provided for the ejection port. For the precompression process for opening this valve, a pressure application controller () controls the pressure applied to the mobile phase within the pump, based on the compressibility of the mobile phase and the amount of compression of the inner wall of the pump resulting from the pressure application, so as to reach the pressure at which the check valve opens before the mobile phase suctioned from the suction port is to be ejected from the ejection port.

Liquid chromatograph

A liquid sending failure detector acquires periodically a liquid sending pressure of a liquid sending mechanism consecutively sends liquid using at least one plunger pump that sends liquid by reciprocally driving a plunger such that a fluctuation is read in one driving period of the liquid sending mechanism, and detect a liquid sending failure of the liquid sending mechanism using an acquired liquid sending pressure. The liquid sending failure detector executes a pulsation detection step of obtaining a fluctuation range of the liquid sending pressure in a certain driving period of the liquid sending mechanism and detecting pulsation on a condition that a count of consecutive periods in which the fluctuation range exceeds a predetermined reference value exceeds a predetermined reference count, and a liquid sending failure detection step of detecting a liquid sending failure of the liquid sending mechanism when the pulsation is detected in the pulsation detection step.

Liquid sending system for liquid chromatograph

A chromatography system includes a liquid sending pump for sending a mobile phase in an analysis flow path, a sample injector that injects a sample into the analysis flow path, a separation column for separating the sample into components, a column oven for storing the separation column and adjusting a temperature of the separation column to a preset target temperature, a liquid sending controller configured to control an operation of the liquid sending pump, and a column protection flow rate setter configured to set a column protection flow rate. The liquid sending controller is configured to control the operation of the liquid sending pump such that, when the liquid sending pump starts sending the mobile phase, the flow rate of the mobile phase flowing through the analysis flow path does not exceed the column protection flow rate until a temperature in the column oven reaches the target temperature.

Chromatography system

A liquid chromatograph includes a liquid sending pump for sending a mobile phase, a sample injector that injects a sample into an analysis flow path through which a mobile phase from the liquid sending pump flows, a separation column that is provided on the analysis flow path and is to separate a sample that has been injected into the analysis flow path by the sample injector into components, a pressure sensor for detecting a liquid sending pressure in the analysis flow path located at a position farther upstream than the separation column, a damper capacity holder that holds an internal capacity of a system through which a mobile phase from the liquid sending pump flows as a damper capacity, a reference value determiner configured to determine a reference value of a fluctuation range of the liquid sending pressure when a liquid sending failure of the liquid sending pump occurs, using at least the damper capacity held by the damper capacity holder, and a liquid sending failure detector that is configured to periodically acquire a liquid sending pressure detected by the pressure sensor, obtain a fluctuation range of the liquid sending pressure in a certain driving period of the liquid sending pump and detect a liquid sending failure using the obtained fluctuation range and the reference value determined by the reference value determiner.

Liquid sent by a liquid sending pump flows through an analysis flow path. A sample is injected into the analysis flow path. A separation column is provided in the analysis flow path. A sample injected in the separation column is separated into components, and sample components obtained by separation are detected by a detector. The number of liquid sending pumps and a connection structure of the liquid sending pumps connected to the analysis flow path are specified by a system configuration specifier as a system configuration. A condition for detecting a liquid sending failure in a liquid sending pump that is preset for each type of system configuration is held by a condition holder. A condition corresponding to a system configuration is determined from conditions held by the condition holder. A liquid sending failure in a liquid sending pump is detected with use of the determined condition.

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Kyoto, Japan

Daisuke Kitabayashi