JPS63103309A - Automatic chemical analyzer - Google Patents

Abstract

PURPOSE:To prevent the idle heating state of a heater by stopping automatically energization of the heater when a water level less than the reference value is detected. CONSTITUTION:An annular constant-temperature bath 1 of an automatic chemical analyzer is filled with the isothermal water 2 and kept a fixed temperature. The water 2 is obtained by leading the water in a water supply tank 6 into a heat bottle 9 via a three-way valve 7 and a pump 8 and heated by a heater 10. A reaction solution 4 is added into the water 2 together with a reaction cell 3 and the absorbance is measured by a photometric system 5 in response to the reaction state. In this case, a level sensor 12 is provided to the water in the bath 1 and the detecting signal for water level is sent to a control part 13. The part 13 consists of a microprocessor, etc., and functions to stop energization to the heater 10 when the detecting signal received from the sensor 12 is less than a reference level L1. Thus an overheat state, etc., can be avoided.

Description

[Detailed Description of the Invention] [Objective of the Invention] (Industrial Application Field) The present invention is an automatic method for measuring the absorbance inside a reaction cell with the reaction cell placed in constant temperature water heated to a predetermined temperature by a heater. Regarding chemical analysis equipment.

(Prior art) Human serum, etc. is used as a sample, a desired reagent is added to cause a chemical reaction, and the state of this reaction is optically measured to provide photometric data for renal diagnosis. An automatic chemical analyzer is known. In order to photometrically measure the reaction state inside the reaction cell using such an analyzer, it is necessary to maintain the reaction cell into which the sample and reagent have been dispensed at a constant predetermined temperature. Measurements are performed while the device is placed in a constant temperature bath filled with constant temperature water heated to a predetermined temperature.

(Problems to be Solved by the Invention) Incidentally, in such automatic chemical analyzers, electricity is often applied to the heater without supplying water to the thermostatic chamber, resulting in so-called dry heating. There was a risk of burning out the equipment.

The present invention was made in order to solve such problems, and it is an object of the present invention to provide an automatic chemical analyzer that automatically stops energizing the heater when water is not supplied. .

[Structure of the Invention] (Means for Solving the Problems) In order to achieve the above object, the present invention includes a level sensor that detects the level of constant-temperature water, and a heater that stops energizing when the water level falls below a reference level. It is characterized by comprising a control means for stopping the vehicle.

(Function) When the level sensor constantly detects the water level of the constant temperature water and detects that it has fallen below the reference level, the control means receives this result and outputs a control signal to stop energizing the heater. Therefore, the operation of the heater is immediately stopped, thereby preventing overheating or overheating.

(Embodiment) Fig. 1 is a block diagram showing an automatic chemical analyzer according to an embodiment of the present invention, in which an annular constant temperature bath 1 is filled with constant temperature water 2, and this constant temperature water 2 is kept at a constant temperature, for example, 37°C. It is set to hang.

The constant temperature water 2 is produced by sucking water in a water tank 6 through a three-way valve 7 with a pump 8 and guiding it into a heat bottle 9.
It is obtained by being heated by a heater 10 placed in a heat bottle 9, and is constantly circulated.

A plurality of reaction cells 3 into which a reaction solution 4 consisting of a sample and a reagent is injected are arranged in the constant temperature water 2, and are driven to rotate in a constant cycle.

A photometry system 5 is arranged in the middle of the reaction cell 30 rotation path,
This photometry system 5 is configured such that when a reaction cell 3 crosses an optical path 5b directed from a light source 5a offset by δ2 on the inner circumferential side of an annular constant temperature bath 1 to a detector 5C provided on the outer circumferential side, the reaction inside the reaction cell 3 is detected. The absorbance according to the reaction state of the liquid 4 is measured and output as photometric data. 'E :'A Encounter 1
A level sensor 12 consisting of a float switch or the like is provided for the constant temperature water 2 inside, and this level sensor 12 always detects the water level of the constant temperature water 2 and sends this detection signal to the control section 13. Assuming that the optical path 5b in the photometry system 5 is fixed at level L, the level sensor 1
It is desirable that water level 2 is at a certain level (reference level) 11 or higher, which is higher than this level. These L
The level difference between L1 and L1 is set to, for example, 2 to 3 m, and setting this level difference is a necessary condition for suppressing variations in photometric data.

The control unit 13 is composed of a microprocessor, etc., and the detection signal inputted from the level sensor 12 is
A control operation in which it is determined whether the level is higher or lower than level L1, and if the level is higher than L1, the heater 10 is continuously energized, and if it is 11 or lower, the heater 10 is stopped energized. I do. 11 is a radiator.

Next, the operation of this embodiment will be explained.

Water is sucked from a water supply tank 6 by a pump 8 and heated by a heater 10 in a heat bottle 9 to provide constant temperature water at a predetermined temperature to the constant temperature bath 1. In this state, when the water level below the reference level is detected by the level sensor 12 and this detection signal is output to the control unit 13, the water control unit 13 immediately operates to stop the power supply to the heater 10. .

Therefore, from now on i! Since the constant temperature water 2 is not heated, overheating will not occur.Also, even if the constant temperature water 2 in the constant temperature bath 1 is rarely empty, or even if there is only a very small amount of water, the same operation will be performed to prevent dry boiling. be done.

On the other hand, if the level sensor 12 detects a water level that is one or more above the reference level, this is a desirable state, and the control unit 13 causes the heater 10 to continue to be energized.

FIG. 2 shows another embodiment of the present invention, in which a second level sensor 14 is provided inside the heat bottle 9 instead of the previous embodiment. This second
The level sensor 14 always detects the water level L2 of the constant temperature water 2 in the heat bottle 9, and this detection signal (second detection signal) is sent to the control unit 13 together with the detection signal (first detection signal) from the level sensor 12. Output to. The control unit 13 performs a logical product (AND) of both signals, and outputs both level sensors 12.
14 are both above the predetermined levels L1 and 12, the heater 10 is energized, and when either or both are below the level, the heater 10 is de-energized.

Therefore, in the case of this embodiment, the level sensor 12 and the second
Even if only one of the level sensors 14 is at or above the reference level, the heater 10 is not energized. This makes it possible to prevent overheating and emptying when the water level not only in the constant temperature bath 12 but also in the heat bottle 9 is below the reference level.

As described above, according to the embodiment of the present invention, it is possible to prevent the heater from running dry, thereby avoiding the danger of burning out the device.

In addition, if a water level below the standard level is detected and it is necessary to stop the power supply to the heater, an alarm will be generated or a caption will be displayed on the display. ! It is also possible to give a visual or visual warning, thereby making the surroundings more reliably aware of the occurrence of danger.

[Effects of the Invention] As described above, according to the present invention, when a water level below the %i%j level is detected, the power supply to the heater is automatically stopped, thereby preventing the heater from running dry. Can be done.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an automatic chemical analyzer according to an embodiment of the present invention, and FIG. 2 is a block diagram showing an automatic chemical analyzer according to another embodiment of the present invention. 1... Constant temperature (carbon dioxide, 2... Constant temperature water, 3... Reaction cell, 5... Photometry system, 5b... Optical path, 8... Pump,
9... Heat bottle, 10... Heater, 12.1
4...Level sensor, 13...Control unit.

Claims (3)

[Claims] (1) Place the reaction cell into which samples and reagents are dispensed in a constant temperature bath filled with constant temperature water heated to a predetermined temperature by a heater, and create an optical path from the constant temperature water to the inside of the reaction cell. An automatic chemical analyzer for measuring the absorbance of water, characterized by comprising a level sensor for detecting the level of the constant temperature water, and a control means for stopping power supply to the heater when the water level falls below a reference level. Chemical analyzer. (2) The automatic chemical analyzer according to claim 1, wherein the reference level of the water level is set at a position higher than the optical path. (3) The heater is disposed in a heat bottle filled with constant temperature water, and a second level sensor is provided in the heat bottle, and the control means is configured to control at least one of the level sensor and the second level sensor. The automatic chemical analyzer according to claim 1 or 2, wherein the automatic chemical analyzer stops energization when detecting a water level below a reference level.