JPH0119085Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a constant temperature vacuum dryer for analyzing chemical samples such as pharmaceuticals.

[Conventional technology]

The moisture content and volatile component content of chemical substances such as pharmaceuticals are one of the important characteristics in terms of quality, and these quantities are generally measured by a loss on drying test method.

Generally, substances with a low melting point, substances that decompose at high heating temperatures, and substances that do not easily absorb moisture are heated under reduced pressure using a desiccant for a certain period of time, and the loss on drying is measured.

The conventional constant-temperature vacuum dryer shown in Fig. 3 has a cylindrical container 1 made of heat-resistant glass material, a table 2 with a built-in electric heater inside it, and a lid 3 made of metal material provided at the opening. It is something. In the figure, 4 is a vacuum suction pipe, and 5 is a glass container containing a chemical sample. In such a device, a large amount of heat is radiated from the circumferential surface of the container 1 and the lid 3, and in addition, radiant heat cannot be used, so the heating efficiency is poor and there is a problem in accuracy.

Further, in the conventional example shown in FIG. 4, an elongated horizontal container 6 made of a heat-resistant glass material and having one end closed is held in a support 7 having a heat-insulating structure, and the opening of the container 6 is made of a heat-resistant glass material. A lid 8 is provided. Furthermore, a desiccant container 9 is connected to the outer end of the container 6, and a decompression pipe 10 is provided, and a base plate 11 is inserted into the container 6, and a plurality of glass containers containing samples are placed on top of the base plate 11. 12. In the figure, 13 is an electric heater.
In this case, a part of the container 6 has a support 7 having a heat insulating structure.
Since the container 12 is exposed from the inside, the temperature distribution inside the container 6 lacks uniformity, and the internal temperature fluctuates depending on the position of the container 12, causing problems in terms of accuracy.

[Purpose of invention]

The present invention was developed in view of the above circumstances, and it solves the problems of the conventional technology by simple and rational means. A constant temperature analyzer that is sealed with aluminum material with good thermal conductivity, eliminates temperature variations at different positions within the container, and efficiently applies radiant heat to the sample, making it possible to maintain a constant sample temperature with high accuracy. The purpose is to provide a vacuum dryer.

[Means for solving problems]

The constant-temperature vacuum dryer for analysis of the present invention, which solves the problems of the conventional technology described above, places a glass container containing a sample in a sealed container heated by a heat source such as an electric heater, and removes the moisture content of the sample under reduced pressure. In a dryer that evaporates volatile components and measures the moisture content and volatile component amount of the sample, the container is made of a metal material with good thermal conductivity such as aluminum, and the outer periphery of the container is covered with a heat insulating material. , and the opening of the container is covered with a lid having a heat insulating material on the outer surface.

〔Example〕

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

FIG. 1 is a partially cutaway front view, and FIG. 2 is a plan view of the same.

21 is a main body of the dryer, and on one side of the upper part of the main body 21 is a container 2 which is open at the top and made of a metal material with good thermal conductivity such as thick aluminum.
2 is provided. An electric heater 23 is provided at the bottom of the container 22.
is tightly fitted into an outer case 24 made of a heat insulating material.

One end of a pressure reducing pipe 25 is connected to the center bottom of the container 22, and a container 26 containing a desiccant is connected to the middle of this pipe 25. Further, a lid 27 whose one end is pivotally supported on the main body 21 is attached to the opening of the container 26 so as to be openable and closable. This lid body 27 includes a lid body 27b made of a metal material with good thermal conductivity such as aluminum,
The entire upper surface is formed by a double structure of an upper plate 27a made of a heat insulating material. In the figure, 28 is an O-ring, 29 is a locking metal fitting, and 30 is a hole for inserting a temperature sensor drilled at an eccentric position on one side of the lid body 27, and a stopper lid 31 made of a heat insulating material is provided in this hole 30. . Reference numeral 32 denotes an inner lid made of a metal material such as aluminum placed on a stepped portion 22a provided on the inner upper part of the container 22, and the inner lid 32 is designed to improve the radiant heat effect. Also, this inner lid 32
A hole 33 is formed at an eccentric position to fit a hole 30 for inserting a temperature sensor provided in the lid 27. Then, remove the stopper lid 31 and open the holes 30, 3.
A temperature sensor (not shown) is inserted into the container through 3 to directly measure the temperature of the sample. In the figure, 34 is a glass container in which the sample is placed;
A sensor 35 measures the temperature of the container itself, and this measured temperature is displayed on a thermometer provided in the main body 21.

〔effect〕

Since the present invention is constructed as described above, it goes without saying that the problems of the conventional technology can be solved. In addition to eliminating temperature variations at the location within the container, it also efficiently applies radiant heat to the sample.
The temperature of the sample can be kept constant with high accuracy, and the moisture content and volatile component content of chemical substances such as pharmaceuticals can be efficiently measured.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway front view of the present invention, FIG. 2 is a plan view of the same, and FIGS. 3 and 4 are sectional views of the conventional example. 21...Dryer body, 22...Container, 23...
Electric heater, 24... outer container, 25... pipe,
26... desiccant container, 27... lid body.

Claims (1)

[Scope of Claim for Utility Model Registration] (a) A glass container containing a sample is placed in a sealed container heated by a heat source such as an electric heater, and water and volatile components of the sample are evaporated under reduced pressure. In a dryer for measuring moisture content and volatile component content: A constant temperature vacuum dryer for analyzing samples of chemical substances such as pharmaceuticals, characterized in that the opening is covered with a lid having a heat insulating material on the outer surface.