Shimadzu Corporation

Takafumi Nakamura

Yoshiaki Maeda

Kenichi Yasunagi

An autosampler includes a pressure release operation unit for performing, by controlling operation of a needle drive mechanism and a switching mechanism, before a tip end of a needle is pulled out from an injection port following a state where a sampling channel is disposed between a feeding device and an analytical column, a pressure release operation of switching the switching mechanism in such a way that the sampling channel is not disposed between the feeding device and the analytical column and a system including the sampling channel is made an open system, and of performing standby until a pressure inside the sampling channel is returned to atmospheric pressure.

Autosampler

A liquid chromatograph analyzing device, which without an analyst having to set complicated processing conditions before measuring a sample, is able to processes unaffected by fluctuations in room temperature and appearance of ghost peaks. In a liquid chromatograph analyzing device, an automatic sampler, a liquid sending pump, a column oven and a detection device are controlled by a calculation processing device. In addition to chromatograph creation unit, which creates chromatograms of a sample based on input detection signals, the calculation processing device has a correction parameter holding section and correction formula setting unit. The correction formula setting unit provides to the liquid chromatograph analyzing device a functionality for the analyst to set correction formulas for incorporating in the chromatograms created by the chromatograph creation unit changes to environmental conditions such as fluctuations in temperature around the liquid chromatograph analyzing device.

Liquid chromatography analyzing device

The invention provides a needle moving device which can detect a fault in a signal provided by a system controller to a performing device. An X-direction driving motor () and a Y-direction driving motor () in a driving portion () of an autosampler () are provided with encoders () for measuring moving distances of a needle () in respective directions from rotation numbers of the respective driving motors (and). A determining portion () provided to a system controller () locates a position of the needle () after the movement based on signals from the encoders () and determines whether the position is a position of a designated sample vessel.

Needle moving device

An autosampler is provided with a needle, a measuring pump which sucks and discharges liquid through the needle, a movement mechanism for the needle, and an injection port which has a needle sealing surface. A sample liquid is sucked into the needle and then the sample liquid discharged with the tip of the needle pressed to the needle sealing surface. When cleaning the needle sealing surface, a cleaning liquid within the injection port is sucked and then the cleaning liquid is discharged and sucked into the injection port at a position at which the tip of the needle does not make contact with the needle sealing surface. Alternatively, after the cleaning liquid is discharged into the injection port, the needle may be caused to perform an up and down motion such that the tip of the needle contacts the needle sealing surface and then is lifted.

Autosampler with control unit for performing a cleaning operation

The present invention provides an analyzing system with which a serial analysis inclusive of a pretreatment can be easily performed in a liquid chromatograph, and even unskilled users can perform a desired analysis. The analyzing system according to the present invention includes: an edit screen display sectionfor displaying an edit screen for allowing a user to create a pretreatment program using an external variable; a batch table display sectionfor displaying a batch table used for serially executing a plurality of analyses, the batch table having an external-variable setting field for allowing the user to enter the aforementioned external variable; and a serial analysis execution sectionfor serially executing each of the analyses inclusive of a pretreatment operation of an auto-sampler according to the pretreatment program and the batch table.

Analyzing system for liquid chromatograph and control program for the same system

An easy and inexpensive signal readout method is provided for a photodiode array consisting of n pieces of photodiodes whose signals are sequentially read out from the first through nth photodiodes. The method includes a canceling process that is performed one or more times before performing a complete readout operation for sequentially reading out signals from all the photodiodes, and the canceling process includes the steps of sequentially reading out signals of a predetermined number of photodiodes starting from the first photodiode to cancel the signals of these photodiodes and then returning to the readout of the signal of the first photodiode. According to this method, it is possible to easily set an appropriate charging time for each photodiode and yet prevent the photodiodes from becoming saturated.

Photodiode array and signal readout method for the same

Provided is a differential refractive index detector having a light receiving element, a zero glass, a zero glass driving unit and a storing portion, and is capable of performing purging operation thoroughly based on a unified standard. The light receiving element receives a measuring light passing through cells (S, R) to generate a slit image. The zero glass makes the slit image parallelly move on the light receiving element. The zero glass driving unit makes the zero glass rotate. The storing portion stores a rotating angle of the zero glass when the same solution fills up the two cells (S, R). When a purging operation for replacing a reference solution in the flow cell is performed, the stored rotating angle is taken as a standard value for being compared with a current rotating angle of the zero glass. If the two angles are the same, the purging operation is finished.

Differential refractive index detector

Adjustment of a differential refractometer includes the steps of (a) equally focusing a slit image on separate portions of a photodetector, (b) decreasing the quantity of light of measuring beam, (c) making parallel movement of the slit image on the photodetector by a predetermined displacement, and (d) increasing the quantity of light of the measuring beam.

Growing community of inventors

Kyoto, Japan

Takafumi Nakamura