JPH0513272B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to an automatic analyzer, particularly a sample collecting and dispensing device used in an automatic biochemical analyzer for serum and the like.

(b) Prior art An automatic biochemical analyzer separates a sample, such as serum, into a reaction tube, dilutes it with a diluent, adds a reagent to it, mixes it, and reacts, and then transfers this reaction solution to a flow cell in the measuring section. The most commonly used devices are those that measure the absorbance by suctioning into the air. By the way, in this automatic analysis, when collecting serum etc. from the sample tank, if foreign substances such as fibrin generated in serum are mixed in the sample, these foreign substances will be sucked out as the sample is collected and the separation will be interrupted. Note: This will cause the nozzle to become clogged. If the dispensing nozzle becomes clogged, the amount of sample dispensed will fluctuate and the analysis operation must be interrupted. However, as a means of detecting the suction of foreign matter, a pressure sensor is inserted into the liquid flow path, and the pressure There is a way to detect anomalies in values. However, using a pressure sensor is expensive,
Furthermore, the complexity of the channel configuration adversely affects the dispensing accuracy.

(C) Purpose The present invention was made with the object of solving the above-mentioned problems and providing a new means for detecting whether foreign matter is clogged in the dispensing nozzle using a simple mechanism.

(d) Configuration Next, the configuration of this invention will be explained.

The sample collection/dispensing device according to the present invention uses a pulse motor to drive the pump when the pump suctions and discharges the sample at the dispensing nozzle, and when aspirating the sample, the pulse motor sends out the sample. A circuit for discriminating the waveform of a pulse signal is configured to determine the hunting state of the waveform, thereby detecting clogging of a dispensing nozzle with foreign matter. That is, this invention aspirates and separates a specimen contained in a specimen container,
A dispensing nozzle for discharging and injecting the suctioned and fractionated specimen into the reaction tube, a pump for causing the dispensing nozzle to suction and discharge the specimen or suction and send out pure water, and a drive means for driving this pump. In a specimen collection/dispensing device comprising a drive circuit and a control circuit for the drive means, the drive means is a pulse motor, and the load on the pump drive system is determined by discriminating the waveform of the pulse signal from the pulse motor. It is characterized by being provided with a waveform discrimination circuit that discriminates the magnitude of the waveform.

(e) Examples Examples of the present invention will be described below based on the drawings.

FIG. 1 is a schematic diagram showing the outline of the configuration of a sample collection/dispensing device which is an embodiment of the present invention. This sample collection dispenser includes a dispensing nozzle 11, a three-way switching valve 1
2, a pump 13, a pulse motor 14 for driving the pump 13, a drive circuit 15 and a control circuit 16 for the pulse motor 14, a waveform discrimination circuit 17 for a pulse signal output from the pulse motor 14, and the like. Its operation will be briefly explained. First, the dispensing nozzle 11 is set to the position indicated by the solid line, and with the dispensing nozzle 11 and the pump 13 communicating with each other via the three-way switching valve 12, the pulse motor 14, the spur gear 18, and the threaded rod are connected. 19, power is transmitted by the horizontal rod 20, and the vertical rod 2
Lower 1. As a result, the sample 23 contained in the sample container 22 is suctioned and fractionated into the dispensing nozzle 11 . Next, the dispensing nozzle 11 is moved to the position indicated by the two-dot chain line, and the dispensing nozzle 11 is
The pulse motor 14 is rotated in the opposite direction while the pump 13 remains in communication with the pump 13 in the flow path, and its power is transmitted to the vertical rod 21 to raise it. As a result, the sample collected by the dispensing nozzle 11 is discharged and injected into the reaction tube 24. Thereafter, the three-way switching valve 12 is switched to connect the pure water container 25 and the pump 13 in a flow path. In this state, the pulse motor 14 is driven and the vertical rod 21 is lowered to draw pure water 26 into the pump 13. Next, the three-way switching valve 12 is switched again, and the pulse motor 14 is driven to raise the vertical rod 21 while the dispensing nozzle 11 and the pump 13 are in fluid communication with each other. As a result, pure water 26 is dispensed into the nozzle 1.
1 to the reaction tube 24. Then, the dispensing nozzle 11 is moved again to the position indicated by the solid line to return to the initial operation.

In this dispenser, the waveform discrimination circuit 1
7 is provided, by which the state of hunting in the waveform of the pulse signal sent out from the pulse motor 14 is determined, and the presence or absence of clogging in the dispensing nozzle is detected. That is, the waveform discrimination circuit 17 determines the magnitude of the load on the pulse motor 14 during sample aspiration. At this time, if the waveform at point a becomes as shown in FIG. 2A, the load is light and there is no foreign material clogging, indicating normal operation. On the other hand, if the waveform hunting at point a is small as shown in FIG. 2B, the load is high, and the dispensing nozzle 11
You can see that there is a foreign object stuck in the. In addition, during waveform discrimination, AC amplification is performed only for section b,
The presence or absence of a blockage may be determined by detecting that the output is smaller than in a normal state.

(f) Effects The sample collection dispenser according to the present invention has the above-described configuration, so it can be manufactured at a lower cost than a dispenser using a pressure sensor, and it can also be manufactured at a lower cost than a dispenser using a pressure sensor. Since there is no need to insert
The flow path configuration is simple and does not adversely affect dispensing accuracy.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram showing the outline of the configuration of a sample collection/dispensing device which is an embodiment of the present invention, and FIG. 2 is a diagram showing the relationship between the waveform of the pulse signal output from the pulse motor and the presence or absence of clogging. FIG. 11...Dispensing nozzle, 12...Three-way switching valve, 1
3...Pump, 14...Pulse motor, 15...
... Drive circuit, 16 ... Control circuit, 17 ... Waveform discrimination circuit, 22 ... Sample container, 23 ... Sample, 24
...Reaction tube, 25...Pure water container.

Claims (1)

[Claims] 1 A dispensing nozzle for aspirating and dispensing the sample contained in a sample container and discharging and injecting the aspirated sample into the reaction tube, and a dispensing nozzle for discharging the sample or suctioning and sending out pure water with this dispensing nozzle. a pump for driving the pump, a driving means for driving the pump,
In a sample collection/dispensing device comprising a drive circuit and a control circuit for the drive means, the drive means is a pulse motor, and the waveform of the pulse signal from the pulse motor is discriminated to determine the magnitude of the load on the pump drive system. A sample collection/dispensing device characterized by being equipped with a waveform discrimination circuit for discriminating.