JPS58115363A - Temperature controlling method - Google Patents

Abstract

PURPOSE:To exercise control of temperature with a small change of temperature and in a small and simple structure, by transmitting the heat from a generator of uniform heat via a heat insulating plate. CONSTITUTION:The heat of a heat generator 15 is transmitted to a metallic generator 14 of uniform heat. Then a hollow block 11 is heated via a heat insulating plate 13 which has a close contact with the generator 14. Owing to this heat atenuating constitution, the temperature change of the block 11 is reduced. Thus the temperature is controlled in a small and simple structure via a temperature measuring matter 17 set at the side of the generator 14.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is directed to an am adjustment method which causes very little temperature fluctuation and is suitable for temperature adjustment of a detector for IIIKI single-body chromatography.

A liquid chromatograph detector is a liquid chromatograph detector.
This device converts changes in physical quantities such as the Shibagai coefficient, refractive index, dielectric constant, and conductivity of the solution distilled from the column into electrical signals. By the way, since all of these physical quantities are temperature dependent, precise temperature control is required to obtain excellent stability/reproducibility or an a madogram. In particular, since liquid chromatography detectors use a differential method for detection, not only the accuracy of the absolute value of the regulated temperature but also changes in the regulated temperature have a large impact on the results. It is desirable that the value be as small as possible (less than 1000 C). An @*i* clause device that satisfies these requirements is shown in FIG. This temperature control device is a detector 1 that detects the physical quantity of the distillate of the grass chromatograph.
A heating element 3 and a temperature sensing element 4 are attached to the hollow block 2, which is made of a material with a relatively large heat capacity such as aluminum alloy casting.
Temperature control is performed by continuously using a DC continuous proportional type or thyristor phase control type temperature controller.

However, in this type of heat filter 1 section device, when adjusting the temperature, the temperature in block 2 once exceeds the set temperature, and the dead time is long until the heat capacity of block 2 reaches the set temperature. The problem was that it took a long time. Furthermore, the temperature controller 5 is complicated, large-sized, and expensive.

This invention was made in view of the above circumstances, and although temperature fluctuations can be minimized, the structure is simple and small, and the settling time until the set temperature is reached is shortened. The purpose of this method is to provide a variable adjustment method that allows temperature adjustment, and is characterized by transmitting good heat controlled at a constant am from a heat equalizing plate to the object whose temperature is being adjusted through a heat insulating layer. .

The present invention will be described in detail below with reference to the drawings.

FIG. 2 shows an example of a temperature control device to which the one-variation control method of the present invention is applied, and reference numeral 11 in the figure is a hollow block to which the @FltA clause is applied. This hollow block 11
is made of aluminum alloy casting or the like, and a detector 12 such as a differential refractometer of a liquid chromatograph is provided inside the detector. The hollow tiles have a relatively large heat capacity of 0.2 Kcal/'0 or more. A heat insulating plate 13 of approximately the same size as the bottom surface is provided in close contact with the bottom surface of the hollow block 11. The heat insulating plate 13 is made of an elastic material and has a thermal diffusivity of about 0.5 m=''/h, and is made of a sheet with a thickness of approximately one crane. For example, a silicone rubber sheet is preferably used. be.

A uniform heating plate 14 having substantially the same size as the heat insulating plate 13 is provided in close contact with the heat insulating plate 13.

This uniform heating plate 14 includes a heating element 15, a metal plate 16, and a temperature measuring element 17. The heating element 15 is a hollow block 1
A planar heat generating sheet or the like having a size as close as possible to the size of the heat insulating plate 13 is used. The metal plate 16 is for uniformly conducting the heat of the heating element 15 to the heat insulating plate 13, and is made of a metal material with good thermal conductivity, such as an aluminum plate or a copper plate, and is approximately the same size as the heat insulating plate 13.
For example, an aluminum plate with a thickness of sass degree is used. The temperature measuring element 17 is attached to the metal plate 16 and measures the temperature of the metal plate 16, and is a highly sensitive resistance temperature measuring element, thermistor, or the like. And heating element 1
5 and the temperature measuring element 17 are connected to a temperature controller 18KI1. In this case, the temperature regulator 18 is a time ratio separate temperature regulator with an on/off cycle of 5 to 10 seconds and a proportional band of about 1°C.

The hollow block 11, the heat insulating plate 13, and the equalizing heat generating plate 14 are all wrapped in a heat insulating material 19 to provide sufficient heat insulation and prevent thermal disturbance O.

Next, the operation of the temperature control device configured in this way will be explained.

First, the temperature joint device 18 is set to a desired temperature 1t (To). When the temperature of the metal plate 16011m is very low, the heating element 15 generates heat by the temperature regulator 18, the metal plate 16 is heated, and the temperature of the metal plate 16 approaches the set temperature (Tol). The heating element 150 generates heat using a hollow block 1 that has good thermal conductivity and a small heat capacity.
Since the temperature of the metal plate 16, which is not directly thermally connected to the metal plate 1 and the heat insulating plate 13, is controlled, the temperature of the metal plate 16 quickly reaches the set temperature f(To). and,
The temperature of the metal plate 16 fluctuates around the set temperature [(Tol) with the fluctuation value determined by the temperature controller 1B as the upper and lower limits.
6 is conducted to the hollow block 11 via the heat insulating plate 13, but due to the effect of the thermal resistance and heat capacity of the heat insulating plate 13, the temperature fluctuation of the metal plate 16 is sufficiently attenuated and conducted to the hollow block 11. Ru. In this way, the hollow block 11
The temperature gradually changes to the set temperature [(T
o), and eventually reaches the set temperature f (Tol), but the temperature fluctuation becomes extremely slight. Finally, the hollow block 11 is heated by the metal plate 16 maintained at the set temperature f (To). Therefore, the temperature of the hollow block 11 does not have an overshoot phenomenon exceeding the set temperature, and as a result, the settling time until the temperature of the hollow block 11 reaches the set temperature is shortened.

Figure IN3 shows the am change of each part of the above-mentioned warm node apparatus. In the figure, the curved line B shows the state of temperature rise of the metal plate 16 to the set temperature, and the curve B shows the state of temperature rise of the hollow block 11 to the set temperature. Note that - line C is shown in FIG.
It shows the temperature increase state of the hollow block 2 due to @.

In the apparatus shown in FIG. 2, the heat insulating plate 13 has a thickness of 0.5 mm.
1E11 silicone rubber seam) Using an aluminum plate with a thickness of 3 mm as the metal stack 6, find out how much the temperature fluctuation of the heating element 15 is attenuated and transmitted to the hollow block 11. It was found that when temperature fluctuations are considered to be sinusoidal fluctuations, the difference is approximately 1/3. Furthermore, when comparing the delay time for temperature fluctuations in the conventional device shown in FIG. 1 with the delay time in temperature fluctuations in the device shown in FIG. 2, it was found that the temperature of the metal plate 16 in the device of the present invention It can be seen that the temperature of the hollow block 2 of the conventional device is lower than that of the conventional device.

Therefore, it was confirmed that the @variable adjustment method of the present invention enables control with less dead time and shortens the temperature settling time.

In the above example, the soaking heat generating plate 14 is made up of the metal plate 16 and the heating element 17, but the invention is not limited to this. ,
A structure in which the temperature measuring element 17 is attached to a thick metal plate 16 may also be used.

As explained above, the temperature control method of the present invention is such that heat controlled at a constant a degree from a uniform heating element is transmitted to an object to be temperature-controlled via a heat insulating plate. , a rounded, normal circuit structure in which temperature fluctuations in the heating element are sufficiently attenuated and heat is transferred to the object 5! Even by using a simple and compact time-proportional temperature fv4 regulator, temperature control with sufficiently suppressed AF fluctuations is possible, and ii [the entire system can be constructed in a small size and at low cost.

Moreover, overshoot phenomenon is prevented and settling time is shortened. Therefore, the temperature control device of the present invention is suitably used in devices that require highly accurate temperature I11 clauses, such as temperature control devices for liquid chromatograph detectors and other analytical instruments.

[Brief explanation of drawings]

Fig. 1 is a schematic block diagram showing a conventional temperature control device; Fig. 2 is a schematic block diagram showing an example of a temperature control device to which the temperature adjustment method of the present invention is applied; It is a graph showing the hollow block and metal plate of the device and the rising state of the hollow block of the conventional temperature joint device. 11...Hollow block, 13...Insulating board, 14...Soaking heating plate, ll5--Heating element, 16...Metal plate, 17 −・・・Temperature measuring body,
111---Temperature controller. Chrysanthemum t 1 (1 ζ'72 Figure 11 □98i-藺

Claims (1)

[Claims] At the same time, a heat insulating plate and a heat-equalizing plate are placed in close contact with the object to be adjusted, and a temperature measuring element is provided on the heat-equalizing plate, and the temperature-controlled heat from the temperature-controlled plate is applied to the object. A temperature control method characterized by heat transfer.