JPH089773Y2 - Reagent heating device in sample analyzer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a compact reagent warming device that can bring a reagent used in a sample analyzer to a predetermined temperature with a small fluctuation range. .

[Conventional technology]

2. Description of the Related Art Conventionally, there has been used a device for heating by electrically immersing an electrically insulated heating wire in a liquid to be heated. Japanese Patent Laid-Open No. 53
Japanese Patent Laid-Open No. 41292 discloses a device in which a quartz glass tube is spirally formed and a heater having a heating wire enclosed therein is used. Japanese Patent Publication No. 60-46656 discloses a device in which a device for making the liquid level constant is added to the device disclosed in the above-mentioned publication.

In these devices, a liquid temperature detector is provided in the vicinity of the liquid discharge port of the liquid storage container accommodating the liquid to be heated and the heater so that the liquid temperature is detected and the power supply of the heating wire is turned on / off. Has become.

[Problems to be solved by the device]

In the conventional device, the heat from the heating wire is first transferred to the air in the glass tube, then to the glass tube and then to the liquid near the glass tube. The heated liquid near the glass tube transfers heat to the liquid near the liquid temperature detector mainly by the liquid flow. This heat transfer rate is considerably slower than that in metal. Also, it is greatly affected by the velocity of the liquid flow. Further, since the volume of air in the glass tube is large, the temperature of the glass tube does not immediately drop even when the heating wire is turned off.

For this reason, the liquid temperature may become considerably constant as compared with the set temperature in a part of the liquid, and bubbles easily occur in the liquid. Further, there is a problem that the fluctuation range of the liquid temperature is wide and the fluctuation range easily changes depending on the flow velocity. Further, there are many difficult steps such as glass processing when the quartz glass pipe is sealed in the liquid reservoir and work for sealing the heating wire in the quartz glass pipe, resulting in high processing cost. Moreover, there is a problem that it is made of glass and there is a risk of breakage. Another problem is that since the heating wire is on / off controlled, noise disturbance is likely to occur in other electric circuits.

The present invention was made in order to solve these problems, and controls the heat generation of the power transistor linearly, that is, linearly to face the group of reagent solution flow channels in a metal block that maintains a constant temperature. The object of the present invention is to provide a reagent warming device in a sample analyzer which can be made compact, has small fluctuations in liquid temperature, is low in cost, and has high safety by being configured to be provided.

[Means for solving the problem]

The reagent warming device in the sample analyzer of the present invention has a group of metal pipes (stainless steel pipes) facing each other on opposite sides of a constant temperature block (aluminum block, for example) made of a metal having high thermal conductivity. (In the drawing, the case of distributing to the left and right is shown as an example), the end of the metal pipe is connected with a pipe to form a reagent flow path, and the metal pipe of the constant temperature block is formed. A recess is provided substantially in the center between the groups, a linear control circuit unit and a power transistor are arranged in the recess, and the power transistor and the temperature detection sensor (thermistor) of the linear control circuit unit are thermally conductively attached to the constant temperature block. Further, it is characterized in that all of these components are covered with a heat insulating material.

[Action]

The heat generated from the power transistor is conducted through the aluminum block to the group of stainless steel pipes that are embedded in opposition to each other, and is transferred from the stainless steel pipe to the reagent liquid flowing inside the pipe.

Since aluminum and stainless steel have good thermal conductivity, the temperature of the reagent solution rises in a short time. Since the heat capacity of the power transistor is much smaller than that of the aluminum block, the amount of heat remaining in the power transistor is small. Further, since the heat generation amount of the power transistor is linearly controlled, the temperature fluctuation of the aluminum block becomes small.

〔Example〕

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. However, unless otherwise specified, the materials, shapes, relative positions, etc. of the constituent members described in this embodiment are not intended to limit the scope of the present invention to them only, and are merely descriptions. It's just an example.

FIG. 1 is a perspective view showing an embodiment of the device of the present invention, and FIG. 2 is a sectional view taken along the line AA in FIG. However, the heat insulating material 7 in FIG. 2 is not shown in FIG. FIG. 3 shows a linear control circuit.

In the figure, reference numeral 1 denotes a metal that transmits heat well, for example, a block made of aluminum (hereinafter referred to as aluminum block 1). Reference numeral 2 denotes a pipe made of metal, for example, stainless steel (hereinafter referred to as stainless pipe 2). As shown in FIG. 2, a plurality of stainless pipes 2 are embedded in an aluminum block 1 having an H-shaped cross section with both ends partially exposed. The end of the stainless steel pipe 2 forms a flow path in which a plurality of stainless steel pipes 2 communicate with each other by a pipe 3 made of a synthetic resin, for example, vinyl chloride (hereinafter referred to as a vinyl chloride pipe 3), outside the aluminum block 1. Are joined together. A power transistor 4 and a linear control circuit unit 5 are attached to a recess 9 in the center of the aluminum block 1.

The temperature detecting thermistor 6 is embedded in the aluminum block 1 near the stainless pipe 2. It is appropriate that the position is about 1/4 from the outlet of the communicating channel length as shown in FIG. The entire component described above is covered with a heat insulating material 7.

FIG. 3 is a circuit diagram showing the periphery of the linear control circuit unit 5, the power transistor 4, and the thermistor 6. A box enclosed by a broken line shows a circuit block, and 8 is an AC input terminal.
A rectifying / smoothing unit that converts a low-voltage AC voltage input from 10 into a DC voltage. Reference numeral 11 is an amplifier, and 12 is a temperature error detector. The amount of heat generated by the power transistor 4 is calculated by a temperature error detection unit including a Zener diode 13 and resistors 14, 15, 16, and 17.
It is linearly controlled according to the temperature difference (error) between the set temperature and the temperature detected by the thermistor 6 detected at 12. The larger the temperature difference, the larger the amount of heat generation. However, heat is generated only when the detected temperature is lower than the set temperature. Since the linear control circuit unit 5 is a low voltage circuit and is linearly controlled, it does not give noise to other electric circuits.

Although one power transistor 4 is shown in FIG. 3, it can be divided into several power transistors to generate heat. The heat generated from the power transistor 4 is conducted to the stainless steel pipe 2 through the aluminum block 1 and is transferred from the stainless steel pipe 2 to the reagent solution flowing in the stainless steel pipe 2. The thermal conductivity of metal is good,
When the inner diameter of the stainless steel pipe 2 is reduced, the liquid amount is small and the temperature of the reagent liquid rises in a short time. Further, since the thermal conductivity is good, the temperature difference depending on the location in the aluminum block 1 is small. Since the heat capacity of the power transistor 4 is extremely smaller than that of the aluminum block 1, the amount of heat remaining in the power transistor 4 is small. Further, since the heat generation amount of the power transistor 4 is linearly controlled, the temperature variation of the aluminum block 1 is small. Therefore, the reagent in the stainless steel pipe 2 rarely exceeds the set temperature, and bubbles are unlikely to occur in the liquid.

In the device of the embodiment, as the power transistor 4
Using two 35 W ones, a reagent at 3 ° C. was flowed at a flow rate of 40 ml per minute through a stainless pipe 2 having an inner diameter of 3 mm and a length of 1.7 m. The liquid temperature at the outlet of the stainless steel pipe 2 is 22 ℃ + 1 ℃ and 22 ℃ when the set temperature of the linear control circuit section 5 is 22 ℃.
It was within the range of -2 ° C.

[Effect of device]

Since the reagent warming device in the sample analyzer of the present invention is configured as described above, it has the following effects.

(1) A plurality of metal pipe groups are provided so as to face each other, a recess (a recess) is provided substantially in the center between the metal pipe groups of the embedded constant temperature block, and a power transistor and a linear control circuit are disposed in the recess. Since the power transistor and the temperature detection sensor of the linear control circuit are mounted in a constant temperature block in a heat conductive manner, and the whole is covered with a heat insulating material, the device is compact and the power transistor is connected to the pipe. Is more evenly distributed, so that the heat transfer to each pipe is more evenly distributed, and the reagent can be brought to a predetermined temperature with a small fluctuation range.

(2) With the above configuration, the rate of heat transfer is high and the control of heat generation is good, so the temperature fluctuation of the reagent is small. Further, since the liquid temperature of the reagent does not rise excessively, the generation of bubbles is small. Moreover, it does not affect other electrical circuits in the analyzer.

(3) Processing is easier than glass, and cost can be reduced. Also, there is no risk of breakage compared to glass.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of a reagent warming device in the sample analyzer of the present invention, and FIG. 2 is AA in FIG.
FIG. 3 is a circuit diagram showing the linear control circuit section, the power transistor, and the surroundings of the thermistor. DESCRIPTION OF SYMBOLS 1 ... Aluminum block, 2 ... Stainless steel pipe, 3 ... PVC pipe, 4 ... Power transistor, 5 ... Linear control circuit part, 6 ... Thermistor, 7 ... Thermal insulation material, 8 ... Rectification smoothing part, 9
... Concave part, 10 ... AC input terminal, 11 ... Amplifying part, 12 ... Temperature error detecting part, 13 ... Zener diode, 14,15,16,17 ... Resistance

Claims (1)

[Scope of utility model registration request] 1. A reagent in which a plurality of metal pipe groups are embedded facing each other at opposite sides of a thermostatic block made of a metal having a high thermal conductivity, and the ends of the metal pipes are connected by pipes. A flow path is formed, a recess is provided substantially in the center between the metal pipe groups of the constant temperature block, a linear control circuit unit and a power transistor are arranged in the recess, and a power transistor and a temperature detection sensor of the linear control circuit unit are provided. Is attached to a thermostat block in a heat conductive manner, and further, these constituent elements are all covered with a heat insulating material. A reagent warming apparatus in a sample analyzer.