JPH0886781A - Column-thermostat quick cooling type gas chromatograph - Google Patents

Abstract

PURPOSE: To enable quickly cooling air in a column thermostat by providing an external cooling device, and providing a quick-cooling air inlet at a specific angle to the direction in which hot air is discharged for cooling, and directing the inlet downwards. CONSTITUTION: A column thermostat 2 is cooled to an initial analysis temperature and held at a constant temperature in preparation for the next analysis. To cool the column thermostat after heating, first time discharging door 7 of thermostat hot air discharging mechanisms 8, 12 is opened and hot air in the column thermostat 2 is expelled out of the column thermostat 2. The hot air expelled by operation of an external cooling device and cold air 90 degrees or more away from the hot air are forcibly fed into the column thermostat 2 through cold air drawing holes 9, 10; i.e., the hot air in the thermostat is expelled out of a gas chromatograph main body 1, and the cold air is drawn into the column thermostat 2 for replacement of air, and acts to quickly lower the temperature inside the thermostat. Therefore, the time required for cooling the column thermostat 2 is almost cut in half and time efficiency of analysis can be significantly enhanced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is provided in a gas chromatograph for the purpose of rapidly cooling the temperature in a column thermostat, and in particular, a gas chromatograph equipped with a rapid cooling device outside the column bath and its installation position. Related to the structure including.

[0002]

2. Description of the Related Art In a gas chromatograph that raises the temperature in a constant temperature bath, it is necessary to cool the inside of the bath in order to return it to the original temperature or lower after the completion of the analysis. Conventionally, as this cooling method,
There were three ways. (1) At the time of cooling, there is a method in which the front door of the column constant temperature tank is fully opened and forced cooling is performed, and there is a method in which the operator manually opens the door and a method in which the door is automatically opened and closed. In this case, the warm air is blown out to the front side, which is a safety issue. (2) In addition to the constant temperature oven door, an auxiliary door is designed, and this door is opened during cooling to blow out hot air. In this case, since cold air does not enter the tank, it is difficult to cool the hot air in the tank in a short time. (3) Two auxiliary doors are provided, one for exclusive use of discharge and the other for exclusive use of sucking in cold air from the outside.
Compared with (2), the cooling rate was faster and could be improved. However, it became expensive in terms of price.

[0003]

As described in the prior art,
In the past method, the temperature inside the tank rises as a result of the temperature rise. This achieves the desired analysis, but in routine analysis, this is repeated and repeated. Therefore, the faster the temperature is raised and the temperature is returned to the original temperature, the shorter the waiting time for the next analysis becomes, and the number of times of analysis can be increased. That is, the period of one analysis cycle is shortened, and improvement in analysis efficiency can be expected. In each of the conventional techniques, an auxiliary door is provided to suck air around the gas chromatograph having a temperature lower than the temperature inside the column thermostat and replace it with warm air inside the column thermostat to cool it. Since the auxiliary door was opened when the air in the warm column constant temperature chamber was discharged to the outside of the chamber, new air was sucked into the column constant temperature chamber and the inside of the chamber was gradually cooled, so it took time to cool. The throughput of the analysis is improved by minimizing the time of one cycle (the temperature in the constant temperature bath is kept at a low temperature before the analysis after the temperature rising analysis). An object of the present invention is to use a conventional thermostatic chamber air inlet hole to forcibly draw cold air outside the column thermostatic chamber into a warm column thermostatic chamber to rapidly cool the air in the column thermostatic chamber. It is to provide a device that can do this.

[0004]

In order to achieve the above object, according to the present invention, a heater for heating in a column thermostatic chamber,
In a gas chromatograph equipped with a fan for agitating air in the tank, a mechanism for discharging hot air in the tank, and an air inlet in the tank, an external cooling device for rapid cooling of the column thermostat outside the column thermostat and the cooling air intake hole There is provided a gas chromatograph, which is characterized in that the column constant temperature bath is cooled by sharing the column. Further, in order to achieve the above object, according to the present invention, in the gas chromatograph described above, in order to rapidly cool the air in the constant temperature oven, 90% or more of the direction of the hot air for cooling by the hot air exhaust mechanism in the vessel is discharged. There is provided a structure of a gas chromatograph provided with an air inlet for rapid cooling in a direction in which the angle is changed and further equipped with an external column constant temperature bath rapid cooling device with the inlet facing downward.

[0005]

In the present invention configured as described above,
First, in order to perform the analysis, the temperature of the column thermostat is kept constant at the initial analysis temperature. Usually, the temperature of the column constant temperature bath is raised at a constant rate as the sample is introduced. At this time, the air in the tank is stirred by the fan for stirring the air in the tank in the constant temperature column. It has a structure that does not leak air outside the tank. The temperature rise ends and the analysis ends. Then, in preparation for the next analysis, the temperature of the column constant temperature bath is cooled to the initial analysis temperature and kept at a constant temperature. The operation of the present invention is as follows when cooling is performed after the temperature rise. First, the discharge door of the hot air discharge mechanism in the tank opens, and the hot air in the tank is discharged to the outside of the column constant temperature tank. At this time, the external cooling device is actuated, and the discharged hot air and cold air that is diverged by 90 ° or more are forcibly drawn into the column thermostatic chamber through the cooling air drawing hole. That is,
The hot air in the tank is pushed out of the main body of the gas chromatograph,
The cold air is drawn into the column thermostat to replace the air, and the temperature inside the bath is quickly cooled. Further, the hot air is blown out of the main body and flows upwardly of the main body, so that the suction port is directed downward and the cold air is sucked in as much as possible, so that the cooling effect is large.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A gas chromatograph and a rapid cooling method therefor according to an embodiment of the present invention will be described with reference to FIGS.

FIG. 1 shows the structure (plan view) of the gas chromatograph of this embodiment.

1 is a gas chromatograph main body case, 2 is the inside of a constant temperature bath, 3 is a column, 4 is a partition plate inside the constant temperature bath,
5 is an air agitating fan in the column constant temperature bath, 6 is a column constant temperature bath heater, 7 is an auxiliary door, 8 is a hot air exhaust duct, 9 is a forced external air suction duct, 10 is an external air suction port, 1
1 is a fan motor, 12 is a fan for discharging air in the main body, 1
Reference numeral 3 is an outside air intake air, 14 is a flow of the intake air at the time of forced cooling, 15 is a flow of the hot air in the column constant temperature chamber at the time of exhausting, 16 is a flow of discharging hot air at the time of cooling, 17
Is a front door of the column constant temperature bath, 18 is a shaft of a motor, 19 is a heat insulating wall of the column constant temperature bath, and 20 is a fan motor for sucking air for forced cooling.

FIG. 2 shows the structure of a conventional gas chromatograph, (1) shows the internal state of the column thermostat at the time of temperature rise,
(2) shows the internal state of the column constant temperature bath during cooling. Hereinafter, the temperature raising process and the cooling process of the constant temperature bath of the prior art and the present invention will be described in order.

FIG. 3 is a diagram showing the flow of air during the temperature raising process and the cooling process of the constant temperature bath of the prior art and the present invention.

FIG. 4 is a time chart showing the temperature raising process and the cooling process of the present invention.

First, the initial temperature temp ₁ to the temperature temp ₂
During time T ₂ to T ₃ , the temperature is increased at a temperature increase rate α ° C./min.

In the temperature raising process, the column constant temperature bath heater 6 increases the temperature by applying a heater current that increases with time.

Then, when temp ₂ is reached, temperature control is performed to keep the temperature constant between T ₃ and T ₄ .

At this time, a constant current is applied to the column constant temperature heater 6, and the temperature in the column constant temperature tank is constant in combination with the stirring effect of the air stirring fan 5 in the column constant temperature tank due to the rotation of the fan motor 11. Kept in.

Since the column constant-temperature bath heater 6 is dangerous when exposed, it is covered by the constant-temperature bath internal partition plate 4. The inside of the column thermostat is kept warm by the heat insulating wall of the column thermostat 19 and the heat insulating portion 17 of the front door of the column thermostat.

When the temperature is further raised from the time T ₇ to T ₈ , the temperature is raised from the initial temperature temp _{1 at a} temperature raising rate β ° C./min. As in the temperature increasing process from T ₂ to T _3, the temperature inside the column constant temperature chamber 2 is increased while increasing the heater current applied to the column constant temperature chamber heater 6 with time.

The steps other than the temperature raising step are as follows.

The time T ₄ between from T ₃ that is held in the temp _2, from T ₄ T ₅ 'between the force for drawing in outside air time,
Time from T ₅ 'T ₅ between until thermostatted column returns to the initial temperature, time between T ₇ from T ₆ is to hold the initial temperature temp _1, T ₇ is the analysis time in the second initial temperature temp ₁ , T ₈ to T ₉ is the second hold time of temp ₂ , T ₉ to T ₁₀ ′ is the second forced outside air suction time, and T ₁₀ is the second column constant temperature bath cooling end time.

When performing repeated analysis many times as in this heating program, the time from T ₄ to T ₅ or T ₉ to T
It is possible to increase the number of analyzes within a certain time by shortening the time between ₁₀ times.

In FIG. 4, 30 is the temperature axis of the column thermostat, 31 is the retention time axis of the analysis, and 32 is the ON state of the air stirring motor in the column thermostat. Reference numeral 33 shows an operating state of the suction motor for a forced chiller according to the present invention.

The air agitation motor 11 shown in FIG. 1 turns around when the power of the gas chromatograph is turned on, and the power is turned off.
It is rotating until it becomes FF. That is, as shown at 32 in FIG. 4, the operation is always ON until the analyst instructs the end of all the analyses.

On the other hand, the forced cooling outdoor air intake motor fan 20 is turned on and off at the timing 33 in FIG.
I do. That is, when the temperature is rising or is controlled at a constant temperature
One analysis is completed in the OFF state, and when cooling the temperature of the column thermostat, that is, during cooling T ₄ to T ₅ ′ or T ₉ to T ₁₀ ′, it is turned on and cold air is externally supplied from the column thermostat. It works to inhale.

At this time, the air stirring motor 11 in FIG. 1 is always in a rotating state. Further, it is desirable that the operation timings of T ₄ and T ₉ during cooling be performed in synchronization with the timing of opening the auxiliary door 7 in FIG.

The heat insulating portion of the front door of the column thermostat 17 in FIG. 1 is opened only when the column in the thermostat is attached or replaced, and is not opened when the inside of the bath is cooled and used in a closed state.

Next, the effect of the present invention will be verified by comparing the performances of the conventional gas chromatograph shown in FIG. 2 and the gas chromatograph of the present invention shown in FIG.

In the conventional gas chromatograph, after the analysis is completed,
As shown in (1) of FIG. 2, the temperature of the column constant temperature bath is lowered to the original temperature before the temperature is raised to prepare for the next analysis.

At this time, the inside of the column thermostatic chamber 2 is sealed and the auxiliary door 7 is closed. This state is from T ₁ to T _{4 in} FIG.
Kept up to. Then, when cooling starts, the state changes to (2) in FIG. 2, the auxiliary door 7 opens, and the heat in the tank is discharged to the outside of the gas chromatograph main body along the exhaust flow of the hot air through the hot air exhaust duct 8. .

Reference numeral 15 is a flow of air when the hot air in the column constant temperature bath 2 is exhausted to the outside of the bath. When this heat is discharged, cold air 13 is sucked from the outside of the constant temperature bath of the column so as to speed up the replacement of the air in the bath.

However, in the conventional structure, as shown in the cooling diagram of FIG. 5, it takes (T ₅ ″ −T ₄ ) time to decrease from the temperature of temp ₂ to the original temperature of temp ₁ as shown by the curve 70. (Temp ₁ : 50 ° C, t
emp ₂ : 300 ° C, (T ₅ ″ -T ₄ ) is about 9 minutes).

The present invention has the structure shown in FIG. 1 for the purpose of shortening the cooling time.

That is, in order to forcibly increase the amount of the outside air sucking air of 13 to quickly dissipate the heat in the column constant temperature chamber 2 and to replace the cold air around the gas chromatograph in a short time, the forced outside air sucking of 9 A duct and a forced cooling air intake motor fan 20 were installed in the gas chromatograph body case 1.

With such a structure, outside air can be introduced into the column thermostat 2 as shown in (3) of FIG.

On the other hand, in the prior art, (1) and (2) in FIG.
As shown in (1), since air is taken in from the inside of the housing of the apparatus at both the temperature rising and the cooling, a very high cooling effect cannot be expected.

Since the present invention takes in outside air at the time of cooling and does not take in outside air at the time of temperature increase, it is possible to have a high cooling effect and a high temperature increasing effect at the same time.

The starting timing of the 20 air intake motor fans for forced cooling is as shown by the curve 33 in FIG. 4, and when cooling from temp ₂ to temp _1, it is turned on at the time T ₄ in FIG. , Start sucking the outside air for forced cooling. Α ₁ ° C lower than the initial temperature temp ₁ temp ₁ −
When the temperature drops to α, the forced cooling air suction motor fan 20 is stopped, and the initial temperature temp ₁ is controlled to a constant temperature up to T ₆ .

In comparison with FIG. 5, in the curve 71 shown by the device of the present invention, the cooling time could be shortened to about half that of the conventional case.
In FIG. 5, T ₄ is the start temperature of cooling, and T ₅ is the initial temperature te according to the present invention.
The time until it stabilizes at mp ₁ (T ₅ ) is the conventional initial temperature te
It is the time until it stabilizes at mp ₁ . Further, by the forced intake of the outside air of the present invention, the air volume at the time of cooling the column constant temperature bath is
It has been confirmed by experiments that the effect can be improved at 16 places in Fig. 1 if the air volume is about 1.5 times or more of the conventional air volume.

Further, as shown in FIG. 6, the inlet of the forced external air suction duct 9 is separated from the hot air discharge duct 8, for example, in the case of a rectangular parallelepiped device, the hot air discharge duct 8 is provided.
By arranging it on a surface different from the one on which it is located, it is possible to prevent the situation in which the heat emitted is absorbed. Further, at that time, if the inlet of the forced external air suction duct 9 is provided downward as shown in FIG. 6, the effect is further enhanced. Further, as shown in FIG. 6, the effect can be improved by providing the hot air exhaust duct 8 above the inlet of the forced external air suction duct 9.

[0039]

【The invention's effect】

(1) By providing an external cooling device, the temperature of the column constant temperature bath can be rapidly cooled, a significant reduction compared with the conventional method can be realized, and the analysis efficiency can be greatly improved. (2) In comparison with the conventional device, an inlet for cooling the outside air is provided at a position 90 ° or more with respect to the hot air exhaust direction in the conventional column thermostat, and the inlet is directed downwards A large cooling effect can be obtained with respect to the rapid cooling, and a large effect on the analysis efficiency is obtained.

[Brief description of drawings]

FIG. 1 is an overall configuration diagram (plan view) of an apparatus according to the present invention.

FIG. 2 is an operation explanatory diagram of temperature rise and cooling of the related art.

FIG. 3 is a view showing a flow of air in a column constant temperature bath according to the present invention.

FIG. 4 is a time chart during temperature rise analysis.

FIG. 5 is a time chart of the present invention and the prior art during heating and cooling.

FIG. 6 is a rear perspective view of the device according to the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Gas chromatograph main body case, 2 ... Inside of a column thermostat, 5 ... Air stirring fan in a column thermostat, 7 ... Auxiliary door, 8 ... Hot air exhaust duct, 9 ... Forced external air suction duct, 10 ... External air suction port, 12 ... Fan for discharging air in the main body, 13 ... Intake air of outside air, 14 ... Flow of suction air during forced cooling, 16 ... Flow of exhausting hot air during cooling,
20 ... A fan motor for forced cooling air intake.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shinji Kurita 1040 Ichimo, Katsuta City, Ibaraki Prefecture, Hitachi Science Systems Co., Ltd. (72) Inventor Hideyasu Chiba 1040 Ichimo, Katsuta City, Ibaraki Prefecture Hitachi Science Systems Co., Ltd.

Claims (2)

[Claims] 1. A gas chromatograph equipped with a heater for heating, a fan for agitating air in the bath, a mechanism for discharging hot air in the bath, and an air intake hole in the bath for rapid cooling of the column bath outside the column bath. A gas chromatograph characterized by being equipped with an external cooling device intended for use, wherein the cooling air supply is shared by an air inlet hole in the tank to rapidly cool the temperature of the column constant temperature tank. 2. The gas chromatograph according to claim 1, wherein
In order to quickly cool the air in the column constant temperature bath, a quick cooling air suction port is provided in a direction that changes the angle by 90 ° or more with respect to the cooling hot air discharge direction by the hot air discharge mechanism in the chamber The structure of the gas chromatograph equipped with a rapid cooling device for the external column thermostatic chamber facing downward.