Abstract: A pump controller causes a first plunger pump and a second plunger pump connected in series or in parallel to perform intake and compression actions alternately at substantially constant cycles, sets a pressurizing chamber of one of the plunger pumps to a state of a higher pressure than the pressurizing chamber of the other plunger pump, and performs flow rate control by adjusting lift amounts of the first plunger and the second plunger. Thus, it is possible to provide a pump for liquid chromatograph, and a liquid chromatograph, which are capable of reducing pulsations even when an ejection flow rate is changed.

Abstract: Disclosed herein is a sample introducing apparatus which is designed such that the analytical flow path runs from the needle to the separation column without the flow path switching means placed at the downstream side of the needle. This design reduces dead volume, which in turn reduces the diffusion of the sample injected into the analytical flow path. Moreover, the absence of the flow path switching means at the downstream side of the needle to inject a sample into the analytical flow path eliminates connection of the pipe with the flow path switching means. This prevents the sample from remaining in the connecting part, thereby reducing sample carry-over and improving the accuracy of analysis.

Abstract: A liquid sample introducing apparatus capable of executing a process with high reliability and high speed is realized. An injection valve includes a sample storage loop connected to a mobile phase flow passage for supplying a sample to a detector of a liquid chromatograph apparatus. A sample is sucked in a needle through a valve and a pipe by a syringe, being introduced to the sample storage loop, being supplied to the mobile phase flow passage. A washing solution from a washing solution bottle is supplied to the needle by a washing unit through the valve and the pipe to wash the inner wall of the needle. The washing solution from the washing solution bottle is supplied to a washing tank by the washing unit through the valve and a pipe to wash the external wall of the needle in the washing tank.

Abstract: Disclosed is a liquid chromatograph provided with: a first flow path switching means which switches between connection of a sample storage loop to a mobile phase flow path and separation of the sample storage loop from the mobile phase flow path; a needle which suctions and discharges a sample; a weighing means which performs suction and discharge of the sample to the needle while weighing the sample; a cleaning solution feeding means which feeds a cleaning solution; a second flow path switching means which switches between at least two types of cleaning solutions; a third flow path switching means which switches between connection of the needle and the weighing means and connection of the needle and the cleaning solution feeding means; and a control means which controls operation of the first flow path switching means, the weighing means, the cleaning solution feeding means, the second flow path switching means, and the third flow path switching means, wherein the total amount of the sample is injected into

Abstract: It is possible to correctly determine whether a change in the pressure or flow rate is caused by normal opening and closing operations of a check valve and to monitor in real time whether an operation of a check valve is normal or abnormal in a liquid supply device. Light is introduced in the check valve and a change in the quantity of light transmitted through or reflected by the check valve, caused by the opening and closing of the valve is detected, so that the opening and closing operations of the check valve can be directly detected. The check valve is arranged in a pipe in the liquid supply device, and a change in the pressure in the pipe is monitored on the basis of a signal from a pressure sensor and a signal which represents the opening and closing of the check valve.

Abstract: A liquid sample introducing apparatus capable of executing a process with high reliability and high speed is realized. An injection valve includes a sample storage loop connected to a mobile phase flow passage for supplying a sample to a detector of a liquid chromatograph apparatus. A sample is sucked in a needle through a valve and a pipe by a syringe, being introduced to the sample storage loop, being supplied to the mobile phase flow passage. A washing solution from a washing solution bottle is supplied to the needle by a washing unit through the valve and the pipe to wash the inner wall of the needle. The washing solution from the washing solution bottle is supplied to a washing tank by the washing unit through the valve and a pipe to wash the external wall of the needle in the washing tank.

Abstract: Both a column having high-pressure resistance and capable of performing high-speed separation and analysis even with a small flow rate and a liquid chromatograph apparatus using the column are provided. A separation column according to the present invention has a monolithic rod being arranged in the center, being made of a porous material, and having a circular cross section, a filler layer arranged such that it encircles a circumferential surface of the monolithic rod, and a cylindrical support medium arranged outside the filler layer. The filler layer is formed by filling a tube-like gap between the monolithic rod and the support medium with particles or beads.

Abstract: Provided is a highly safe chromatography device that does not sacrifice user-friendliness during the addition and replacement of a sample holding container. The chromatography device has doors 10, 11, a door locking mechanism 15, and a sensor 13 for detecting whether the doors 10, 11 are open or closed. The doors 10, 11 are opened and closed to place a sample holding container 6 and a sample rack 1 in the chromatography device. The door locking mechanism 15 is operated to lock the doors 10, 11 when the sensor 13 indicates that the doors 10, 11 are closed and the analysis of a sample in the sample holding container 6 starts, and is operated to unlock the doors 10, 11 when a return operation and a washing operation terminate after a needle 2, a syringe 9, and other mechanical parts operate. Consequently, the sample holding container can be safely added or replaced without having to perform, for instance, a procedure for executing a pause function.

Abstract: A pump controller causes a first plunger pump and a second plunger pump connected in series or in parallel to perform intake and compression actions alternately at substantially constant cycles, sets a pressurizing chamber of one of the plunger pumps to a state of a higher pressure than the pressurizing chamber of the other plunger pump, and performs flow rate control by adjusting lift amounts of the first plunger and the second plunger. Thus, it is possible to provide a pump for liquid chromatograph, and a liquid chromatograph, which are capable of reducing pulsations even when an ejection flow rate is changed.

Abstract: Disclosed herein is a sample introducing apparatus which is designed such that the analytical flow path runs from the needle to the separation column without the flow path switching means placed at the downstream side of the needle. This design reduces dead volume, which in turn reduces the diffusion of the sample injected into the analytical flow path. Moreover, the absence of the flow path switching means at the downstream side of the needle to inject a sample into the analytical flow path eliminates connection of the pipe with the flow path switching means. This prevents the sample from remaining in the connecting part, thereby reducing sample carry-over and improving the accuracy of analysis.

Abstract: A sample rack 1 in which sample holding container 6 containing sample liquid is loaded and cooled via a cooling device 8 includes containing sections 40 adapted to receive the sample holding containers 6, and groove portions 11 disposed with inclination below the bottom surface of the containing section 40. The bottom surface of the containing section 40 communicates with the groove portion 11. The dew condensation water introduced into the groove portion 11 is discharged to the outside of the sample rack 1 via an opening portion 12 provided on the side surface of the sample rack 1. In this way, since the dew condensation water is forcibly discharged, workability encountered during removal of the sample rack and sample cooling capacity can be improved.

Abstract: A liquid sample introducing apparatus capable of executing a process with high reliability and high speed is realized. An injection valve includes a sample storage loop connected to a mobile phase flow passage for supplying a sample to a detector of a liquid chromatograph apparatus. A sample is sucked in a needle through a valve and a pipe by a syringe, being introduced to the sample storage loop, being supplied to the mobile phase flow passage. A washing solution from a washing solution bottle is supplied to the needle by a washing unit through the valve and the pipe to wash the inner wall of the needle. The washing solution from the washing solution bottle is supplied to a washing tank by the washing unit through the valve and a pipe to wash the external wall of the needle in the washing tank.

Abstract: Disclosed herein is a sample introducing apparatus which is designed such that the analytical flow path runs from the needle to the separation column without the flow path switching means placed at the downstream side of the needle. This design reduces dead volume, which in turn reduces the diffusion of the sample injected into the analytical flow path. Moreover, the absence of the flow path switching means at the downstream side of the needle to inject a sample into the analytical flow path eliminates connection of the pipe with the flow path switching means. This prevents the sample from remaining in the connecting part, thereby reducing sample carry-over and improving the accuracy of analysis.

Abstract: Disclosed herein is a stable solvent delivery device capable of delivering solvent both at high pressure and at constant flow rate. A solvent delivery device comprises a plurality of plungers which reciprocate in the respective pump chambers including an eluent charge side pump chamber and an eluent discharge side pump chamber, a motor to reciprocate these plungers, a control unit to control the operation of the motor, valves which are respectively set at the eluent inlet and outlet of the eluent charge side pump chamber, a first sensor to measure the quantity of load received by the plunger in the eluent charge side pump chamber, and a second sensor to measure the pressure of the eluent discharged from the eluent discharge side pump chamber.

Abstract: It is possible to correctly determine whether a change in the pressure or flow rate is caused by normal opening and closing operations of a check valve and to monitor in real time whether an operation of a check valve is normal or abnormal in a liquid supply device. Light is introduced in the check valve and a change in the quantity of light transmitted through or reflected by the check valve, caused by the opening and closing of the valve is detected, so that the opening and closing operations of the check valve can be directly detected. The check valve is arranged in a pipe in the liquid supply device, and a change in the pressure in the pipe is monitored on the basis of a signal from a pressure sensor and a signal which represents the opening and closing of the check valve.

Abstract: A pump device which accurately detects a flow rate of a pump, performs real-time control of the flow rate, and thus can suppress a flow rate error caused by occurrence of pulsation. Control of a pump rotation speed by a pressure sensor has low responsiveness in a low pressure region, and a correlation between a pressure and a flow rate is incomplete in a high flow rate region. With this taken into consideration, a flow rate sensor is disposed at an outlet port of a second pump. A position detection sensor detects a point where a first pump is shifted from a suction mode to a discharge mode. Moreover, the flow rate sensor detects that there is no discharge from the pump, and that there is discharge from the pump alone. Accordingly, a controller sets a rotation speed of a motor to a speed double the previous speed (double the normal rotation speed).

Abstract: Disclosed herein is a separation column comprising a porous block covered with a coating wherein space-free adhesion is attainable therebetween by low temperature process without releasing octadecylsilyl bases and others from the porous block. A monolith rod 1 is covered with a metal or resin coating 2. Then, the monolith rod 1 covered by the coating 2 is further covered with a rod retainer 3 made of a low melting point metal (melting point 100-200 degrees C.) to form a column body 19. Since the rod retainer 3 is formed by pressure molding at low temperature (100-200 degrees C.). It is therefore possible to absorb the surface irregularities of the monolith rod 1 by the coating 2 while octadecylsilyl bases and others from are released when the retainer 3 is formed. This allows the potential separation ability of the porous block to be brought out maximally.

Abstract: A pump device is realized, which accurately detects a flow rate of a pump, performs real-time control of the flow rate, and thus can suppress a flow rate error caused by occurrence of pulsation. Control of a pump rotation speed by a pressure sensor has low responsiveness in a low pressure region, and a correlation between a pressure and a flow rate is incomplete in a high flow rate region. With this taken into consideration, a flow rate sensor 10 is disposed at an outlet port 9 of a second pump 4. A position detection sensor 14 detects a point where a first pump 3 is shifted from a suction mode to a discharge mode. Moreover, the flow rate sensor 10 detects that there is no discharge from the pump 3, and that there is discharge from the pump 4 alone. Accordingly, a controller 15 sets a rotation speed of a motor 12 to a speed double the previous speed (double the normal rotation speed).

Abstract: The present invention provides a separation column including a monolithic rod without a resin coating material. The separation column can prevent the monolithic rod from destroying, and a liquid can be delivered at a high pressure into the separation column. The separation column includes the monolithic rod (monolithic silica rod) in a tapered-columnar shape, and a clad with the interior formed in a tapered-columnar shape. The monolithic rod is built into the clad.

Abstract: Disclosed herein is a stable solvent delivery device capable of delivering solvent both at high pressure and at constant flow rate. A solvent delivery device comprises a plurality of plungers which reciprocate in the respective pump chambers including an eluent charge side pump chamber and an eluent discharge side pump chamber, a motor to reciprocate these plungers, a control unit to control the operation of the motor, valves which are respectively set at the eluent inlet and outlet of the eluent charge side pump chamber, a first sensor to measure the quantity of load received by the plunger in the eluent charge side pump chamber, and a second sensor to measure the pressure of the eluent discharged from the eluent discharge side pump chamber.