JP2000039428A - Column thermostatic chamber - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily maintain the desorption or the like of a column and to accurately control temperature even in the column with various kinds of diversified outer shapes and outer diameters by providing a thermally conductive resin for thermally connecting a column being accommodated inside and an enclosure. SOLUTION: An enclosure 1 accommodates a column 7 inside and is divided into a body A and a lid B to facilitate the maintenance, for example, for exchanging the accommodated column 7. Also, a heat generation source (cooling source) 4 such as a heater or a thermoelectric element is arranged while it is thermally connected, and a temperature sensor 5 for controlling temperature is mounted. Then, a thermally conductive resin 6 for thermally connecting at least one portion of the column 7 and the enclosure 1 is equipped. Although there is no limitation as the thermally conductive resin 6 if it has improved thermal conductivity, a thermally conductive flexible resin whose shape can be changed according to the outer shape and outer diameter of the column 7 to be accommodated is preferable. By using this sort of resin, temperature can be accurately controlled in contact with the column 7 without any gap regardless of the outer shape or the like of the column 7.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a column thermostat used in a liquid chromatograph.

[0002]

2. Description of the Related Art As a column constant temperature device, a jacket device mounted on a column and flowing constant temperature water, a constant temperature water device for immersing the entire column, a block constant temperature device for sandwiching the column between metal blocks of aluminum or the like, and a constant air temperature inside the housing. There is known an air thermostat in which a column is kept inside and a column is housed therein.

[0003]

A jacket device which is attached to a column and in which constant temperature water flows and a constant temperature water device in which the entire column is immersed are frequently used for experimental purposes. However, in these constant temperature apparatuses, water used as a heat medium is liable to be polluted or the like, and there is a problem in use in that maintenance must be periodically performed and replaced.

[0004] The above-mentioned problem does not occur in a block thermostat in which a column is sandwiched between metal blocks of aluminum or the like because no liquid is used. However, if there is a gap between the column and the metal block, the efficiency of heat conduction is reduced. Therefore, when using columns having a wide variety of outer shapes and outer diameters, it is necessary to consider the fluctuations in the heat transfer efficiency of each column, or to replace and use blocks corresponding to the outer shapes and outer diameters of the columns. There are issues. In addition, the column shape is not merely a columnar shape, and in particular, since the end fitting portions at both ends may have different outer shapes and outer diameters from other portions, a metal block suitable for such a column is manufactured. There is a problem that it is difficult. In addition, there is a problem in maintenance such as the need to remove the metal block when replacing the column.

[0005] In the case of a block thermostat, it is possible to cope with columns having different external shapes and outer diameters to some extent by a method such as applying a thermal conductive grease between the column and the metal block to improve the thermal conductivity. However, in this case, there is a new problem that the column is contaminated with grease.

An air thermostat that keeps the air temperature inside the housing constant and houses the column inside the housing can be used irrespective of the dimensions and shape of the column, such as the outer diameter and outer diameter, and also allows maintenance such as desorption of the column. Although easy, air has a problem that accurate temperature control is difficult due to small heat capacity per volume.

Accordingly, an object of the present invention is to solve the above-mentioned problems of the conventional column thermostat, to easily perform maintenance such as desorption of the column, and to perform various operations without contaminating the column with grease or the like. It is an object of the present invention to provide a column thermostat capable of accurately controlling the temperature of a column having an outer diameter and an outer diameter.

[0008]

Means for Solving the Problems To achieve the above object, a column thermostat of the present invention is provided. A column formed of a heat conductor accommodating a column therein is thermally connected to the column. Column thermostat comprising a temperature control means provided with a thermally conductive resin for thermally communicating at least a part of the column housed therein and the housing. It is. Hereinafter, a column thermostat of the present invention will be described in detail based on an embodiment shown in the drawings.

[0009]

FIG. 1 shows the appearance of a column thermostat of the present invention, and FIG. 2 shows a sectional view thereof. The housing 1 of the column thermostat is made of a metal such as aluminum which is a heat conductor. It is preferable to attach a heat insulating material 2 such as urethane foam rubber to the outer surface of the housing. It is particularly preferable to cover the heat insulating material with a metal box or the like.

The housing is constructed so that its internal space 3 is sufficient to accommodate columns having a wide variety of external and external diameters. For example, the column thermostat of FIG. 1 or 2 accommodates both a 4.7 mm diameter column and a 10 cm length column (approximately 15 cm in length including end fittings at both ends) for analysis (center of the figure) and for pretreatment. The size was set to be as large as possible. In the example of FIG. 1 or 2, the outside of the urethane foam rubber is further covered with a steel plate in order to impart mechanical strength to the thermostat.

The housing is divided into at least two parts, for example, a main body A and a lid B, in order to facilitate maintenance such as installing the column 7 inside and further replacing the stored column. Preferably, a heat source (cooling source) 4 such as a heater or a thermoelectric element is arranged on one surface of the main body in a state of being in thermal communication with the heat source, but it may be arranged inside the housing.
For temperature control, preferably, a temperature sensor 5 such as a platinum temperature sensor is attached to the main body, and heat is generated based on the temperature sensor, a heat source (cooling source), and a housing temperature or a housing internal temperature detected by the temperature sensor. A control unit is constituted by a microcomputer (not shown) or the like that operates a source (cooling source) to heat or cool the housing, and controls the temperature to a preset temperature. The term "thermal communication" as used in the present invention means a relation in which heat is transmitted between means or members to be communicated, and the degree is not limited.

The heat conductive resin 6 used in the present invention is not limited as long as it has good heat conductivity, but the heat conductive resin 6 can change its shape according to the outer shape and outer diameter of the column to be stored. Resins are particularly preferred. By using such a resin, it is possible to achieve an effect that the column temperature can be accurately controlled by contacting the resin without any gap irrespective of the outer shape of the column.

As the heat conductive resin, a resin used for heat radiation of a semiconductor such as a heat radiation silicone rubber sheet can be used. As an example, a commercially available resin (Sircon (registered trademark) GR, manufactured by Fuji Polymer Co., Ltd.) can be exemplified. The thermal conductivity of these resins is about 2W · m-1 · K -1
1/100 times of aluminum, 1 of stainless steel
/ 10 times that of ordinary plastics. In the present invention, there is no limitation to use a resin having a higher thermal conductivity, for example, other than these exemplified resins.
The higher the flexibility of the heat conductive flexible resin, that is, the higher the flexibility, the better. It is particularly preferable that the column has such flexibility that the column is easily dented when pressed against the resin.

In the column thermostat of the present invention, at least a part of the column housed inside by the heat conductive flexible resin can be in thermal communication with the housing. More specifically, the resin is spread more than once on the inner surface of the housing,
An example of a device configured to be able to store a column in contact with the resin can be given. In the present invention, preferably,
Wrap the entire column with a thermally conductive flexible resin, or
As shown in (1), a pair of (two) thermally conductive flexible resins is used to sandwich a column housed between them. In such a configuration, the upper surface and the lower surface of the column in the figure are in contact with the resin, and the resin on the lower surface is in communication with the housing, so that the temperature control can be performed more easily and accurately. In particular, in the latter configuration, it is sufficient to remove only the upper resin even when the column is detached.

When two resins are used as shown in FIG. 2, it is sufficient if one of them is in thermal communication with the housing, but both are in thermal communication with the housing. Is particularly preferred. It is particularly preferred that the communication with the column extends over the entire length thereof. As described above, it is preferable that the heat conductive flexible resin is in communication with the housing over as wide a range as possible.

Although there is no particular limitation on the case portion to which the heat conductive flexible resin is in thermal communication, as described above, when the main body and the cover are provided in the column thermostat, the movable cover and the cover may be used. It is preferable to contact the main body, which is an immovable part, rather than the contact of the main body. When thermally communicating with both the lid and the main body, it is particularly preferable that the lid, the thermally conductive flexible resin, and the column be pressed against each other by closing the lid.

The column housed in the column thermostat is:
Although connected to an external pump or the like by a pipe for sending the sample liquid to be analyzed, the liquid supplied to the column through the pipe is usually different from the temperature inside the column thermostat. When the liquids having different temperatures are introduced into the column, it becomes difficult to control the temperature inside the column. Therefore, in the column thermostat of the present invention, preferably, at least a part of the pipe on the column inlet side is in thermal communication with the heat conductive resin. The pipe portion that is in thermal communication with the heat conductive resin is heated or cooled to the same temperature as the column temperature in the process in which the liquid sent at a normal liquid sending speed passes through the pipe and is introduced into the column. Is preferably sufficient. In order to achieve this object, a configuration in which two resins are used as shown in FIG. 2 and the pipe 8 is interposed therebetween can be exemplified. The configuration in FIG. 2 is an example in which a total of three thermally conductive flexible resins are used.

[0018]

According to the column thermostat of the present invention, columns having various external shapes and outer diameters, in other words, columns having different diameters and lengths are accommodated, and the column temperature is controlled with high precision and accuracy. A resulting column thermostat is provided. Furthermore, since the column is indirectly in contact with the housing by the heat conductive flexible resin, an effect of being hardly affected by a small fluctuation of the housing temperature can be achieved.

[Brief description of the drawings]

FIG. 1 is an external view of a column thermostat.

FIG. 2 is a sectional view of a column thermostat.

[Explanation of symbols]

Reference Signs List 1 housing, 2 heat insulating material, 3 internal space, 4 heat source (cooling source), 5 temperature sensor, 6 heat conductive flexible resin, 7
Column, 8 piping, A body, B lid

Claims (3)

[Claims] 1. A column thermostat comprising a housing formed of a heat conductor accommodating a column therein and temperature control means thermally connected to the housing. A column thermostat comprising a thermally conductive resin for thermally communicating at least a part of the column with a housing. 2. The apparatus according to claim 1, wherein the heat conductive resin is disposed so as to cover the entire surface of the column accommodated therein. 3. The apparatus of claim 1 wherein said thermally conductive resin is in thermal communication with at least a portion of the column inlet piping.