JP2002196008A - Autosampler - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an autosampler preventing detection error of a sample cell detecting sensor due to reflected light from fingers gripping a sample cell. SOLUTION: A low reflectivity substance 3c comprising black matt coating is applied to a lower end part of a pair of fingers 3a gripping the sample cell 1. By this, since an infrared ray from a light emitting device 5a of the sample cell detecting sensor 5 is absorbed by the low reflectivity substance 3c and its reflected light is reduced, the detection error due to the reflected light from the fingers 3a can be eliminated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic sample transfer autosampler mainly used in a thermal analyzer.

[0002]

2. Description of the Related Art In a conventional autosampler, a plate-shaped or rod-shaped finger attached to a transfer arm grips a sample cell arranged in a sample tray and transfers it to a detector position. At this time, an optical sensor is arranged near the transfer path of the finger, light is applied to the lower surface of the sample cell being transferred, and the presence or absence of the sample cell is confirmed by detecting the reflected light.

[0003]

In the conventional autosampler, the presence of the sample cell gripped by the finger is detected by the optical sensor as described above. However, in order to reliably detect the presence of the sample cell, the optical sensor is used. Must be close to the sample cell. However, if the optical sensor is too close to the finger, light will also be reflected from the lower end surface of the finger in the direction of the optical sensor, and the optical sensor will react as if there is a sample cell even though the finger is not holding the sample cell. There is a problem that it will. The present invention has been made in view of such circumstances, and has as its object to provide an autosampler that can reliably detect the presence or absence of a sample cell in a transfer process.

[0004]

In order to achieve the above object, an autosampler according to the present invention comprises: a holding section for holding a sample cell containing a sample to be analyzed; and an arm for driving the holding section. In an autosampler equipped with an optical sensor that automatically transfers a plurality of sample cells onto a detector sequentially and detects the presence or absence of a sample cell in a holding unit during transfer, the lower end surface of the sample cell holding unit receives light from the optical sensor. The present invention is characterized in that a low-reflection material that does not reflect incident light is applied, or the lower end surface of the sample cell holding portion is inclined at an acute angle so that reflected light does not enter the optical sensor. By using the above configuration, the autosampler of the present invention can surely confirm the presence or absence of the sample cell being transferred.

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an autosampler according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a perspective view showing a configuration when the autosampler of the present invention is used in a thermal analyzer. This autosampler has a plurality of recesses or through holes 2a for mounting the sample cell 1 and a rotating shaft 2b.
Sample transport mechanism 3 comprising a sample tray 2 having the following structure, a finger 3a for gripping the sample cell 1, and a transport arm 3b for transporting the sample cell 1 to the position of the detector 4.
A sample cell detection sensor 5 for detecting whether or not the sample cell 1 is gripped by the finger 3a being transferred; and a control device 6 for mounting these components and controlling the operation of the components. It is composed of a housing 7 for housing.

A motor M1 for rotating the transfer arm 3b in the horizontal direction as shown in FIG. 2, a motor M2 for moving the finger 3a up and down via the transfer arm 3b, Finger 3a
A motor M3 for opening and closing left and right, and a motor M4 for rotating or stopping the sample tray 2 are incorporated in the sample tray 2, respectively. The sample cell detection sensor 5 includes a light emitting element 5a that emits a light beam toward the sample cell 1 being transferred, and a light receiving element 5b that detects the reflected light.

As shown in FIG. 2, the control device 6 includes a ROM 62 for storing a control program for executing the transfer of the sample cell 1 by the present autosampler, a RAM 63 for transferring data in and out, and an arithmetic operation in the control program. A CPU 61 for executing control, and an I / O for outputting a drive signal for controlling the sample tray 2 and the sample transport mechanism 3 based on a control signal from the CPU 61 and for taking in a detection signal from the sample cell detection sensor 5. It comprises an I / O interface 64, an input device 66 for inputting a command signal for starting automatic analysis and the like, and an I / O interface 65 for an output device 67 for outputting information from the sample cell detection sensor 5.

FIG. 3 shows a finger 3 according to the present invention.
FIG. 2A shows a side view (a) and a front view (b) thereof according to the embodiment of FIG. As shown in FIG.
A low-reflectance substance 3c that does not reflect incident light from the light emitting element 5a of the sample cell detection sensor 5 is applied to the lower end surface of the sample cell detection sensor 5. The light emitting element 5a and the light receiving element 5b can be configured by individually arranging a light emitting diode and a photodiode, but a general-purpose photoelectric sensor in which these are integrated can also be used. For example, when a semiconductor light emitting element such as GaAs that emits infrared light is used as the light emitting element 5a, black luster paint is used as the low reflectance material 3c, and a quantum photodiode or a thermal pyroelectric infrared light is used as the light receiving element 5a. Sensors can be used.

Next, the automatic analysis operation of the thermal analyzer using the above-configured autosampler will be described with reference to FIGS. When an automatic analysis start command is input to the input device 66, the finger 3a is moved together with the transfer arm 3b to a specified position on the sample tray 2 by the motor M1 and is opened left and right by the motor M3. Descend to the position. And finger 3a
Indicates that after holding the sample cell 1 by the motor M3,
2, the sample cell 1 is moved to a certain height by the motor M1 and then transferred to the detector 4 by the motor M1.

The sample cell 1 held by the finger 3a is moved from the sample tray 2 to the detector 4 (FIG. 4).
During the transfer in the direction of the arrow (a), the sample cell detection sensor 5 detects the presence or absence of the sample cell 1. FIG. 4 is a diagram for explaining the operation of the sample cell detection sensor 5 when there is the sample cell 1 (a) and when there is no sample cell 1 (b). That is, when the sample cell 1 is gripped by the finger 3a, the infrared light from the light emitting element 5a is reflected by the lower end surface of the sample cell 1 and enters the light receiving element 5b as shown in FIG. The holding of the cell 1 is confirmed.

On the other hand, when the sample cell 1 is not gripped by the finger 3a, as shown in FIG.
Even if the infrared ray from a strikes the lower end surface of the finger 3a, it is absorbed by the black matte painted surface, so that the incident light of the infrared ray on the light receiving element 5b disappears, and it is ensured that the sample cell 1 is not gripped by the finger 3a. It is confirmed.

The finger 3a stops on the detector 4, and after the sample cell 1 is mounted on the detector 4 by the motor M2, the motors M1 to M3 are driven to return to the sample tray 2. Then, the heating furnace 8 is lowered onto the detector 4, the sample cell 1 on the detector 4 is accommodated in the heating furnace 8 and heated, and thermogravimetry for thermal analysis is performed. When the sample reaches a predetermined set temperature, the thermogravimetry is ended, and the heating operation of the heating furnace 8 is stopped. After the temperature in the furnace has decreased to a preset temperature, the heating furnace 8 rises, and the sample cell 1 whose measurement has been completed by the operation of the finger 3a is transferred from the detector 4 to the original position to complete one cycle. Then, shift to the next cycle. In the next cycle, first, the sample tray 2 is rotated by one pitch, and the next sample cell 1 is moved to a position below the finger 3a.
Then, similarly to the above cycle, the sample cell 1 is gripped by the finger 3a, transferred onto the detector 4, and heated to perform thermogravimetry.

FIG. 5 shows a cross-sectional view and a sample cell detection sensor 5 according to another embodiment of the finger 3a. As shown in the drawing, the lower end of the finger 3d is finished so that its side surface is inclined and the lower end surface has no flat portion. Thereby, the light beam incident on the lower end portion of the finger 3d from the light emitting element 5a is reflected in the arrow direction A deviating from the direction of the light receiving element 5b, so that it is possible to reliably detect that the sample cell 1 is not gripped.

According to the present invention, a low-reflectance material is applied to the lower end surface of the finger to prevent the sample cell detection sensor from being determined to be present even when there is no sample cell due to the reflected light from the lower end surface while the finger is moving. It is characterized by eliminating reflected light by changing the direction of light reflection by inclining the reflection surface.The types of light, low-reflectance substance and finger shape of the sample cell detection sensor are The invention is not limited only to the embodiments.

[0015]

According to the autosampler of the present invention, the presence / absence of the sample cell can be determined by bringing the sample cell detection sensor sufficiently close to the finger. The presence or absence of a cell can be reliably determined.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of an autosampler according to an embodiment of the present invention.

FIG. 2 is a configuration diagram of a control device according to an embodiment.

FIG. 3 is a side view (a) and a front view (b) of the finger of the embodiment.

FIG. 4 shows a sample cell using a finger according to the embodiment (a).
It is operation | movement explanatory drawing in the case of (b).

FIG. 5 is an operation explanatory view of another finger of the embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Sample cell 2 ... Sample tray 3 ... Sample transfer mechanism 3a, 3d ... Finger 3b ... Transfer arm 3c ... Low reflectivity substance 4 ... Detector 5 ... Sample cell detection sensor 5a ... Light emitting element 5b ... Light receiving element 6 ... Control device 66 ... input device 67 ... output device 7 ... housing 8 ... heating furnace 9 ... heating furnace moving mechanism

Claims (1)

[Claims] An arm for driving the holding unit; a plurality of sample cells automatically and sequentially transferred to a detector; In an autosampler equipped with an optical sensor that detects the presence or absence of a sample cell in the holding unit, apply a low-reflection material that does not reflect incident light from the optical sensor to the lower end surface of the sample cell holding unit, or An autosampler wherein a lower end surface is inclined at an acute angle so that reflected light does not enter the optical sensor.