JP6772953B2 - Gas chromatograph oven and gas chromatograph equipment using it - Google Patents

Description

The present invention relates to an oven for a gas chromatograph for controlling the temperature of a column for a gas chromatograph (GC), and a gas chromatograph apparatus using the oven.

In a gas chromatograph device, a gaseous sample is introduced into a column on a flow of carrier gas, and various compounds in the sample are separated in the time direction while the sample passes through the column. Then, the sample gas coming out from the outlet end of the column is introduced into the detector, and the compounds contained in the sample gas are sequentially detected by the detector. The column is housed in a gas chromatograph oven (hereinafter simply referred to as "oven") for temperature control, and the oven keeps the column constant at a predetermined temperature or a predetermined temperature during analysis. The temperature may be adjusted to rise over time according to the heating program of.

The above oven generally has a heater and a fan installed inside an oven chamber having a substantially rectangular parallelepiped shape in which an internal space large enough to accommodate a column is formed, and is provided in front of the oven chamber. The large opening for taking in and out the oven is opened and closed by a side-opening door. Generally, in order to improve the performance of temperature control, the oven chamber is configured to maintain high airtightness when the door is closed.

In a gas chromatograph device, hydrogen gas may be used as a carrier gas. Further, in the gas chromatograph device, a detector that requires hydrogen gas for detection, such as a hydrogen flame ionization detector (FID), may be used. In such a case, if there is a connection failure in the connection part between the column and the sample introduction part or the connection part between the column and the detection part, or if the column or connection device is defective or damaged, hydrogen gas leaks out and the oven is sealed. It may collect in a certain oven room. If the accumulated hydrogen gas ignites for some reason such as heat from a heater or static electricity, an explosion may occur and the constituent members of the oven may be scattered around (see Non-Patent Document 1 and the like). Conventionally, there is an oven described in Patent Document 1 as a measure for reducing such an explosion.

FIG. 7A is a schematic horizontal cross-sectional view of the oven described in Patent Document 1 (however, some elements are shown by end faces in order to avoid complicated drawings). In this figure, the downward facing surface is the front surface, and the upward facing surface is the back surface.
This oven has an oven chamber main body 200 which has a substantially rectangular parallelepiped shape and the entire front surface is open, and a door 213 which opens and closes the front opening of the oven chamber main body 200, and the door 213 is closed. And an internal space 218 for accommodating the column is formed. The oven chamber main body 200 includes a right side wall 201, a left side wall 202, a back wall 203, and a bottom wall 204, which are visible in FIG. 7 (a), and a top wall, which does not appear in FIG. 7 (a). Each wall has a three-layer structure in which a heat insulating material such as glass wool is sandwiched between two metal plates. A motor 210 is attached to the back wall 203, and a fan 211 is fixed to a rotating shaft of the motor 210 extending into the internal space 218. Further, the heater 212 is arranged so as to surround the fan 211.

The door 213 includes a door body 2131, an inner door 2132 made of a heat insulating material such as glass wool, and a spring 2133 that urges the inner door 2132 toward the internal space 218 with respect to the door body 2131. The door body 2131 is rotatably fixed to the oven chamber body 200 (strictly speaking, the left side wall 202) about a door shaft 214 extending in the vertical direction (direction orthogonal to the paper surface in FIG. 7A). As shown in FIG. 7A, when the door 213 is closed, the inner door 2132 is pushed backward by the urging force of the spring 2133. As a result, the inner door 2132 is pressed against the front edges of the upper, lower, left and right side walls 201, 202, etc., and the door 213 substantially seals the oven chamber main body 200.

A substantially L-shaped latch 215 is attached to the right end of the door body 2131 (that is, the end opposite to the door shaft 214) so as to be rotatable around a latch shaft 216 extending in the vertical direction. Further, a hooking portion 217 having a shape that engages with the hook-shaped portion of the latch 215 is fixed to the oven chamber main body 200 (strictly speaking, the right side wall 201). Although not shown, the latch 215 is urged counterclockwise in FIG. 7A by a spring so that the door 213 closes the front opening of the oven chamber body 200, as shown in FIG. 7A. The hook-shaped portion of the latch 215 engages with the hooking portion 217 in the closed state, and the door 213 is securely kept in the closed state. When opening the door 213, the user grips a handle (not shown) on the front of the door 213. Then, the hook-shaped portion of the latch 215 and the hook portion 217 are temporarily disengaged, and the user can open the door 213 forward.

As described above, when the door 213 is closed and the internal space 218 is in a substantially sealed state, if hydrogen gas accumulates in the internal space 218 and ignites, an explosion occurs. Then, the gas pressure rises sharply in the internal space 218. As described above, the inner door 2132 is urged rearward by the spring 2133, but since the gas pressure that rises sharply is superior to the urging force, the inner door is as shown by the white arrow in FIG. 7 (b). The 2132 is pushed by the gas pressure and approaches the door body 2131. Then, a gap is formed between the inner door 2132 and the front edges of the left and right side walls 201 and 202, and gas is discharged from the internal space 218 through the gap. That is, a kind of degassing is performed through the void. As a result, the degree of increase in gas pressure in the internal space 218 is alleviated, and the scale of the explosion can be reduced.

However, this conventional oven has the following problems.
As described above, when the gas is rapidly discharged through the gap between the inner door 2132 and the front edges of the left and right side walls 201 and 202, the force of the gas flow is very strong. When the gas flow hits the latch 215 at the right end of the door 213, a large force is applied to the latch 215 in the direction indicated by the arrow in FIG. 7B, and the hook-shaped portion and the hook portion 217 are disengaged. It may end up. In that case, the door 213 is pushed by the gas pressure applied to the entire inner door 2132, and the door 213 is vigorously opened, and there is a risk of contacting the user in front of the door 213.

Further, in the conventional oven, even if a part of the gas flows out through the gap between the inner door 2132 and the front edges of the left and right side walls 201 and 202, the amount of the outflow is not necessarily large, so that the internal space 218 An explosion occurs when the gas pressure is fairly high. As a result, the magnitude of the explosion tends to be large. Therefore, the members constituting the oven are vigorously scattered around, which may cause human or physical damage due to such scattered objects.

Japanese Unexamined Patent Publication No. 2016-217912 JP-A-2002-14087 (paragraph [0003])

"Safe use of hydrogen gas (Handling precautions) 6. Dangers assumed during gas chromatograph operation", Shimadzu Corporation, [online], [Search on April 28, 2017], Internet <URL: http //www.an.shimadzu.co.jp/gc/support/faq/bombe6.htm ＞

Since the above explosion is caused by improper handling of the device or improper handling of the device, it is unavoidable that the device itself including the oven is damaged, but physical damage to the facility where the device is installed and Naturally, it is desirable to reduce human damage as much as possible.

The present invention has been made to solve these problems, and an object of the present invention is that even when a flammable gas such as hydrogen gas accumulated in the internal space of an oven ignites and an explosion occurs. An object of the present invention is to provide an oven for a gas chromatograph capable of suppressing the scale of the explosion and surely reducing human damage and property damage, and a gas chromatograph apparatus using the oven.

Generally, the main body of the oven chamber of a gas chromatograph oven is assembled into a box shape by welding a thin metal plate such as a stainless steel plate (see Patent Document 2). Due to such a structure, the oven chamber body has a high degree of airtightness and robustness, and has an advantage that it is not easily deformed even when a force is applied from the outside, for example. However, when the above-mentioned explosion occurs in the internal space of the oven chamber, if the oven chamber body is highly airtight and robust, it will not be destroyed until the gas pressure becomes considerably high, and it will exceed the breakdown pressure resistance of the oven chamber. If the gas pressure rises to, a big explosion will occur. That is, the high airtightness and robustness of the oven chamber body can be a factor that causes greater damage to the explosion caused by the ignition of the flammable gas accumulated in the oven chamber.

Generally, as one of measures to prevent the explosion of equipment or containers that may explode inside, such as dust collectors and coal silos, an explosion emission port (explosion vent) is provided. The explosion outlet itself bursts at a preset pressure, quickly releasing the abnormal pressure generated by the explosion inside the device or container to the outside, and preventing damage to the device or container. It is a device that reduces the degree of damage or damage. The present inventor has found that such an explosion-proof method is also effective in a gas chromatograph oven. Then, the present inventor intentionally sets the strength of a part of the oven chamber body to be weaker than that of the other parts, and this relatively weak partial structure is damaged when the gas pressure at the initial stage of the explosion is still relatively low. As a result, the present invention was made with the idea of suppressing the scale of the explosion by forming an opening for releasing the gas pressure to the outside.

That is, the gas chromatograph oven according to the present invention, which has been made to solve the above problems, has a substantially rectangular parallelepiped shape and an oven chamber main body having an open front surface, and a door opening and closing the front opening of the oven chamber main body. In a gas chromatograph oven provided, the oven chamber body and the door form an internal space for accommodating a column.
The main body of the oven chamber is a metal plate member or a substantially flat plate in which the five wall surfaces of the right side, the left side, the bottom surface, the top surface, and the back surface, excluding the front surface, are bent into a substantially U-shape or a substantially L-shape. Formed using at least two metal plate members that are
At least one corner between two adjacent surfaces formed by abutting different metal plate members at substantially right angles, the two metal plate members were connected by a method having a lower strength than welding. It is considered as a connection part for dissipation,
When the gas pressure in the internal space rises above a predetermined level, the emission connection portion is detached, broken, broken, or deformed to form an opening that functions as an explosion emission port. There is.

When gas chromatography analysis is performed using the oven for gas chromatography according to the present invention, the front opening of the oven chamber body containing the column is closed by a door. When flammable gas such as hydrogen gas accumulates in the substantially sealed internal space for some reason and ignites due to heat or static electricity from the heater, an explosion occurs and the gas pressure in the internal space rises sharply. When the gas pressure rises to a certain extent, the pressure causes the metal plate member in the dissipating connection to detach, break, break, or deform to form an opening. Then, since the gas flows out from the internal space through this opening, the sudden rise in gas pressure in the internal space is alleviated. As a result, the scale of the explosion can be small, and the main body and door of the oven chamber, the members such as heaters and fans arranged in the oven chamber, and various members of the main body of the chromatograph device inside the oven chamber are damaged. Even if it scatters, the degree can be suppressed considerably.

In the oven the gas chromatograph according to the present invention, above-mentioned "lower technique strength than welding" may insert the convex piece formed by bending at substantially right angles one metal plate member into insertion opening of the other metal plate member method, or a method of screwing a convex piece formed by bending at substantially right angles one metal plate member to the other metal plate, is either. In the latter case, it is preferable to reduce the width of the convex piece to be screwed. As a result, when the gas pressure rises to a certain extent, the pressure causes not only the convex piece to deform and the screw to come off, but also the convex piece to easily break.

In the oven for gas chromatography according to the present invention, in the oven chamber main body, the right side surface, the left side surface, the bottom surface, the top surface, and the five wall surfaces on the back surface are each of two sheets, an inner metal plate and an outer metal plate. It can have a three-layer structure in which a heat insulating material is sandwiched between metal plates.
In this case, the right side surface, the left side surface, the bottom surface, the top surface, and the five wall surfaces on the back surface arranged inside the heat insulating material (internal space side) are metal bent into a substantially U-shape or a substantially L-shape. Five of the right side surface, left side surface, bottom surface, top surface, and back surface, which are formed by using at least two plate members or metal plate members which are substantially flat plates, while being arranged on the outside (exterior side) of the heat insulating material. Using at least two metal plate members whose surface wall surface is bent into a substantially U-shape or a substantially L-shape or a substantially flat plate-like metal plate member, which is different from the at least two metal plate members. It is formed. At this time, the metal plate member having a substantially frame shape is placed on the right side surface of the right side surface, the left side surface, the bottom surface, and the top surface so as to close between the edge portions of the inner and outer metal plates facing the front surface. , The structure is such that the metal plate member forming the left side surface, the bottom surface, and the top surface is attached so that the inner surface of the door and the metal plate member having a substantially frame shape are in close contact with each other when the door is closed.
Then, a corner portion between two adjacent surfaces formed by abutting the metal plate member having a substantially frame shape and the metal plate member forming the right side surface, the left side surface, the bottom surface, and the top surface at a substantially right angle. Also, it is preferable to use a method having a lower strength than welding to form a radiation connection portion in which two metal plate members are connected.

Further, in the gas chromatograph oven according to the present invention, preferably, when the bent portion of the metal plate member bent into a substantially U-shape or a substantially L-shape is the corner portion, a small hole is formed along the bent position. It is preferable to have a structure in which perforated portions formed intermittently are provided.

The perforated portion is more easily broken than a normal bent portion. Therefore, in the above preferable configuration, the flammable gas accumulated in the internal space is ignited to cause an explosion, and when the gas pressure in the internal space rises to a certain extent, the pressure causes a perforation in addition to the emission connection portion. A break occurs in the portion, and the metal plate sandwiching the broken portion is easily deformed. As a result, a large opening is formed, and gas flows out from the internal space through the opening, so that the sudden rise in gas pressure in the internal space can be further mitigated.

Further, in the gas chromatograph oven according to the present invention, all the corner portions except the bent portion are configured to be a radiation connecting portion in which two metal plate members are connected by a method having a strength lower than that of welding. Good.

Due to the large external size of the gas chromatograph oven, the final assembly plant is built in a location (country) close to the area where it is used, and parts manufactured at another core plant are transported to the final assembly plant at the final assembly plant. It is often assembled into a finished product. In the conventional structure in which the box-shaped oven chamber body is assembled by welding, it is necessary to install welding equipment in the final assembly factory or to transport the box-shaped members manufactured in the core factory to the final assembly factory. In the former case, the cost of welding equipment is high. On the other hand, in the latter case, the box-shaped member having a hollow inside has a high transportation cost.

On the other hand, in the gas chromatograph oven having the above configuration according to the present invention, welding work is not required in the manufacturing process for assembling the oven chamber main body, and the oven chamber is formed by fitting or screwing a plurality of metal plate members. The main body can be assembled. Therefore, it is not necessary to install welding equipment in the final assembly plant. Further, it is not necessary to transport the box-shaped member to the final assembly plant, and a box such as a substantially U-shaped metal plate member, a substantially L-shaped bent metal plate member, or a substantially flat metal plate member, etc. It suffices to transport a large number of members per the same volume to the final assembly plant as compared to the shaped members. Therefore, there is an advantage that both the cost of the manufacturing equipment and the transportation cost of the members can be reduced.

Further, in the gas chromatograph oven according to the present invention, at least a part of the emission connecting portion in which two metal plate members are connected by a method having a strength lower than that of welding is between the two metal plate members. It is recommended to have a playful configuration.

According to this configuration, even when each metal plate member expands and contracts due to heat, the play between the two metal plate members absorbs the expansion and contraction, so that it is possible to avoid applying an unreasonable load to the connecting portion. As a result, high durability can be achieved without cracks that occur in the conventional configuration in which the metal plate members are connected to each other by welding.

Further, as described above, when the right side surface, the left side surface, the bottom surface, the top surface, and the five wall surfaces on the back surface of the oven chamber body each have a three-layer structure, the metal plate inside is extremely hot (when using the oven). For example, the maximum temperature may be about 450 ° C.), whereas the outer metal plate is separated from the inner metal plate by a heat insulating material, so that the maximum temperature is about 150 ° C. Therefore, the temperature difference between the inner metal plate and the outer metal plate sandwiching the heat insulating material may become very large. In a configuration in which a metal plate member having a substantially frame shape is attached so as to close between the edge portions of the inner and outer metal plates facing the front on the right side surface, the left side surface, the bottom surface, and the top surface, respectively. A large temperature difference will occur between the inside and outside of the metal plate member, which has a substantially frame shape. In particular, the force due to thermal expansion and contraction will be concentrated on the four inner corners, causing fatigue failure and cracking. easy.

In particular, in a conventional gas chromatograph oven, a metal plate member having a substantially frame shape is welded to the inner metal plate forming the right side surface, the left side surface, the bottom surface, and the top surface of the oven chamber body, so that the metal plate member has a substantially frame shape. The inner edge of a metal plate member is bent at a substantially right angle, and at that time, relief grooves (notches) are formed at the four corners. As described above, the stress due to the expansion and contraction of the metal plate member due to the large temperature difference between the inner side and the outer side is concentrated in this relief groove, so that a crack is likely to occur from the relief groove portion.

Therefore, in the gas chromatograph oven according to the present invention, the linear portions of the four sides facing inward in the metal plate member having a substantially frame shape are bent rearward at a substantially right angle, and any two adjacent sides are bent. The corners between the straight portions may be substantially arcuate when viewed from the front, and ribs connected to the bent portions of the linear portions on both sides thereof and extending to the rear side may be formed by drawing.

According to this configuration, even if the metal plate expands and contracts due to a large temperature difference between the inner side and the outer side of the metal plate member having a substantially frame shape, the stress due to the expansion and contraction does not concentrate on the corners of the four corners. , Disperse moderately. Therefore, unlike the conventional gas chromatograph oven, the metal plate member having a substantially frame shape is less likely to crack, and high durability can be achieved.

It should be noted that the bent portion of the linear portion of the metal plate member having a substantially frame shape and the metal plate member inside the right side surface, the left side surface, the bottom surface and the top surface of the oven chamber body are not connected by welding, for example, simply bent. By adopting a structure in which the portion is pressed against the metal plate member inside the right side surface, the left side surface, the bottom surface, and the top surface, it is possible to absorb the expansion and contraction of the metal plate member due to the temperature change while ensuring the airtightness.

The gas chromatograph apparatus according to the present invention includes the above-mentioned oven for gas chromatograph according to the present invention, a column housed in the internal space of the oven, a sample introduction unit connected to the inlet end of the column, and the column. It is characterized by including a detection unit connected to the outlet end of the oven.

Here, the detection method of the detection unit is not particularly limited, and various types of detection units generally used in gas chromatograph devices can be used. Further, the sample introduction unit may be any method for introducing the sample, such as one in which the sample vaporized in the sample vaporization chamber is introduced into the column and one in which the gaseous sample collected by the headspace method is introduced into the column.

According to the gas chromatograph oven according to the present invention and the gas chromatograph apparatus using the same, even if a flammable gas such as hydrogen gas accumulated in the internal space of the oven chamber ignites and an explosion occurs, the explosion occurs. Can be surely reduced as compared with the conventional device. As a result, for example, it is possible to prevent the door from opening vigorously and prevent an accident such as the door hitting the user and injuring the user. Further, by reducing the degree of explosion, it is possible to suppress the degree of scattering of various members constituting the oven and various members of the gas chromatograph apparatus main body in which the oven is installed to the surroundings at the time of explosion. ..

FIG. 3 is an external perspective view of a gas chromatograph apparatus main body in which an oven for gas chromatograph according to an embodiment of the present invention is housed in an open door state. The perspective view of the oven chamber main body of the oven for gas chromatograph of this Example. The perspective view of the oven chamber main body of the gas chromatograph oven of this Example seen from the direction different from FIG. The figure which shows the assembly structure of the oven chamber main body of the oven for gas chromatograph of this Example. The figure for demonstrating the deformation state of the oven chamber main body when an explosion occurs in the internal space in the gas chromatograph oven of this Example. The schematic block diagram of the gas chromatograph apparatus of this Example. A schematic horizontal cross-sectional view (a) of a conventional gas chromatograph oven with the door closed, and a partially horizontal cross-sectional view (b) showing a state immediately after an explosion occurs in the internal space.

Hereinafter, an embodiment of a gas chromatograph oven according to the present invention and a gas chromatograph apparatus using the same will be described with reference to the accompanying drawings.

FIG. 6 is a schematic configuration diagram of the gas chromatograph device of this embodiment.
The oven chamber main body 10 of the gas chromatograph oven, which will be described later, is housed in the gas chromatograph apparatus main body 4, and the sample vaporization chamber 1 and the detector 6 are attached to the gas chromatograph apparatus main body 4. A capillary column 5 is housed in the internal space 11 of the oven chamber main body 10, and the inlet end of the capillary column 5 is connected to the sample vaporization chamber 1 and the outlet end is connected to the detector 6. The detector 6 is not particularly limited in its method, and is, for example, a hydrogen flame ionization detector (FID).

An appropriate carrier gas such as hydrogen gas or helium gas is supplied to the sample vaporization chamber 1 through the carrier gas flow path 2. The sample vaporization chamber 1 is heated to an appropriate temperature, and when a small amount of liquid sample is dropped from the injector 3, the sample is vaporized in a short time and introduced into the capillary column 5 along with the flow of carrier gas. In the case of the split injection method, most of the gas is discharged from the inside of the sample vaporization chamber 1 to the outside through a split flow path (not shown), and only a part of the gas is introduced into the capillary column 5.

The oven is controlled so that the temperature rises with the passage of time according to, for example, a predetermined heating program, and the compounds in the sample gas are separated in the time direction while the sample gas passes through the capillary column 5, and the detector 6 is used. Will be introduced sequentially in. The detector 6 generates a detection signal according to the amount of the introduced compound and inputs it to a signal processing unit (not shown). The signal processing unit creates a chromatogram based on the obtained detection signal.

In this gas chromatograph device, for example, if the connection between the capillary column 5 and the sample vaporization chamber 1 is improper, hydrogen gas used as a carrier gas accumulates in the internal space 11, and if the hydrogen gas ignites for some reason, it explodes. May cause. Even if such an explosion occurs, the oven chamber main body 10 has a characteristic configuration so as to reduce the degree of the explosion. Next, the characteristic configuration of the oven chamber main body 10 will be described.

FIG. 1 is an external perspective view of the gas chromatograph apparatus main body 4 containing the oven for gas chromatograph of this embodiment with the door open, FIGS. 2 and 3 are perspective views of the oven chamber main body 10, and FIG. 4 is a perspective view of the oven chamber main body 10. FIG. 5 is a diagram showing an assembled structure, and is a diagram for explaining a deformed state of the oven chamber main body 10 when an explosion occurs in the internal space 11. For convenience of explanation, in FIGS. 1 to 4, the width direction of the oven chamber main body 10 is the X direction, the depth direction perpendicular to the X direction is the Y direction, and the height direction perpendicular to both the X direction and the Y direction is the Z direction. It is said.

As shown in FIG. 1, the gas chromatograph apparatus main body 4 has a substantially rectangular parallelepiped housing 41, and an operation unit 42 provided with operation buttons and a display panel is provided on the right side of the front surface of the housing 41. There is. The oven chamber main body 10 having an opening of almost the entire front surface is housed inside the housing 41, and the front opening of the oven chamber main body 10 can be opened and closed by the door 12.

As shown in FIG. 2, the oven chamber main body 10 has a substantially rectangular parallelepiped shape, and includes a right side wall portion 10a, a left side wall portion 10b, a top surface wall portion 10c, a bottom surface wall portion 10d, and a back surface wall portion 10e. At the front edge ends of the right side wall portion 10a, the left side wall portion 10b, the top surface wall portion 10c, and the bottom surface wall portion 10d, a frame-shaped front frame portion 10f that comes into close contact with the inner peripheral edge portion of the door 12 when the door 12 is closed. Is installed. The five surfaces other than the front surface of the oven chamber main body 10, that is, the right side wall portion 10a, the left side wall portion 10b, the top surface portion 10c, the bottom surface portion 10d, and the back surface portion 10e are all two pieces of metal, inner and outer. It has a three-layer structure in which a heat insulating material such as glass wool is sandwiched between plates (however, in this example, the metal plate on the outside of the bottom wall portion 10d is substantially a part of the housing 41). ..

As shown in FIG. 4, the main members constituting the oven chamber main body 10 are an inner first metal plate member 101 having a substantially U-shaped front view and an inner second metal plate having a substantially inverted L-shaped side view. Metal is applied to the member 102, the outer first metal plate member 103 which is substantially U-shaped in top view, and the aluminum foil or glass sheet which is not shown in FIG. 4 but is visible in FIG. 2 or 3. The outer metal foil member 104, which is a sheet or the like, the outer second metal plate member 105, which is not shown in FIG. 4, but is visible in FIG. 2, and the front frame metal plate member 106, which has a substantially frame shape. ,.

The inner first metal plate member 101 is a single metal plate member that forms an inner wall on the right side wall portion 10a, the bottom surface wall portion 10d, and the left side wall portion 10b. The inner second metal plate member 102 is a single metal plate member that forms the inner surface wall of the top wall portion 10c and the back wall portion 10e. The outer first metal plate member 103 is a single metal plate member that forms the outer surface wall of the right side wall portion 10a, the back wall portion 10e, and the left side wall portion 10b. Further, the outer metal foil member 104 is wound so as to cover the entire outer side of the heat insulating material in the bottom wall portion 10d, the top surface wall portion 10c and the side surface wall portions 10a and 10b, and the outer first metal plate member 103 is the outer first metal plate member 103. It is mounted on the outside of the outer metal foil member 104. The outer second metal plate member 105 is a member mounted on the outer metal foil member 104 in the top wall portion 10c. In addition, in FIG. 2 and FIG. 3, reference numerals attached to each member in FIG. 4 are shown in parentheses ().

In a conventional oven, a joint of metal plate members is connected by welding to form an inner wall surface facing the main body of the oven chamber, particularly the internal space 11. On the other hand, in the oven of this embodiment, the joint between the inner first metal plate member 101 and the inner second metal plate member 102, for example, the upper edge ends of the side wall portions 10a and 10b and the left and right sides of the top surface wall portion 10c. The corners formed by abutting the edge at a substantially right angle are fixed to each other by fitting and screwing.

Specifically, as shown in FIG. 4, the upper edge of the inner first metal plate member 101 corresponding to the side wall portions 10a and 10b is bent inward at a substantially right angle to form the overlapping portion 1011. Although it is formed, an insertion port 1012 elongated in the Y direction is formed at an appropriate portion of the bent portion. On the other hand, on both side edge edges of the portion of the inner second metal plate member 102 corresponding to the top wall portion 10c, convex piece portions 1021 extending in a tongue shape are formed on both sides at a position corresponding to the insertion port 1012. Has been done. By inserting the plurality of convex piece portions 1021 into the corresponding insertion ports 1012, the overlapping portion 1011 is brought into close contact with the portion of the inner second metal plate member 102 corresponding to the top wall portion 10c (reference numeral A in FIG. 2). The part indicated by).

Further, as shown in FIGS. 3 and 4, a substantially L-shape bent outward at a substantially right angle to the upper edge edge of the portion of the outer first metal plate member 103 corresponding to the side wall portions 10a and 10b. The extension piece 1031 is formed. The extension piece 1031 is screwed to the outer second metal plate member 105.

Further, the front frame metal plate member 106 is basically fixed to the outer first metal plate member 103 by inserting and screwing the metal plate member. That is, as shown in FIGS. 2 to 4, both the left and right sides of the front frame metal plate member 106 having a substantially frame shape are bent at a substantially right angle to the rear side, but extend further rearward from the bent portion in a tongue shape. A plurality of convex piece portions 1062 having different extension lengths are formed. On the other hand, at the leading edge of the portion of the outer first metal plate member 103 corresponding to the wall portions 10a and 10b on both sides, an insertion port 1032 elongated in the Z direction at a position corresponding to the three convex piece portions 1062 on the central side. Is formed. The three convex piece portions 1062 on the center side of the front frame metal plate member 106 are fixed by being inserted into the insertion port 1032, and the upper and lower two convex piece portions 1062 of the front frame metal plate member 106 are outer first. It is screwed to the metal plate member 103.

The front frame metal plate member 106 and the inner first metal plate member 101 and the inner second metal plate member 102 are not inserted or screwed, but are simply pressed against each other to bring them into close contact with each other to form a joint between the two. I try not to create a gap. That is, the corners 1061 at the four inner corners of the front frame metal plate member 106 have a shape having a substantially arcuate roundness. The straight portions of the four sides of the front frame metal plate member 106 that face inward are bent rearward at substantially right angles to form an overlapping portion 1063, but the corner portions 1061 at the four corners also overlap on both sides. An extension portion 1064 that is continuously connected to the portion 1063 and extends rearward is formed. The extending portion 1064 bent at a substantially right angle at such a curved corner portion can be satisfactorily formed by drawing by pressing. When the front frame metal plate member 106 is fitted into the inner first metal plate member 101 and the inner second metal plate member 102, the overlapping portion 1063 is the front edge end of the inner first metal plate member 101 and the inner second metal plate member 102. It is pressed against the inside of the part, and there is almost no gap between the two. Further, by forming the extending portion 1064 at the corner portion 1061 at the four corners, there is an advantage as described later.

Further, as shown in FIGS. 3 and 4, the outer first metal plate member 103 has a substantially right angle between the portion corresponding to the side wall portions 10a and 10b and the portion corresponding to the back wall portion 10e. Small holes 1033 are intermittently formed in the bent portion from the upper end and the lower end by a length of about 1/4 to 1/3 of the total length (see reference numeral D in FIG. 3).

A circular or rectangular opening is formed in a portion of the inner first metal plate member 101 corresponding to the wall portions 10a and 10b on both side surfaces, and these openings are different metal plates from the internal space 11 side. It is closed by the member 107.

In the gas chromatograph device of the present embodiment using the oven chamber main body 10 having the above configuration, hydrogen gas accumulates in the internal space 11 in which the door 12 is closed and is substantially sealed, and the hydrogen gas is ignited by heat or static electricity from the heater. Then an explosion occurs. Then, the gas pressure rises sharply in the internal space 11. As described above, the portion of the oven chamber main body 10 fixed by inserting the metal plate member is easily removed when the gas pressure in the internal space 11 increases to some extent. Further, since the portion screwed by the convex piece portion 1021 or the like having a narrow width has low mechanical strength, it breaks when the gas pressure in the internal space 11 increases to some extent. Further, in the portion where the small holes 1033 are formed intermittently, the thin connecting portion between the adjacent small holes 1033 is easily broken.

That is, since the corner portion of the oven chamber main body 10 having the above-mentioned structure has lower strength than the flat portion of the metal plate member, when the gas pressure in the internal space 11 increases to some extent, it is damaged or broken in advance. It is destroyed and an opening is formed. Once the opening is formed, the gas tries to flow out from the opening at once, so that the metal plate member is deformed and the opening is further expanded. Specifically, as shown by the alternate long and short dash line in FIG. 5, each metal plate member is deformed to form a plurality of large openings. This opening functions as an explosion emission port, and gas is discharged from the internal space 11 through this opening to alleviate an increase in gas pressure in the internal space 11 and reduce the scale of the explosion. As a result, it is possible to suppress the degree to which not only the oven chamber main body 10 but also various members constituting the gas chromatograph device main body 4 are scattered around, and it is possible to reduce human damage and physical damage.

Further, as described above, in the oven of the present embodiment, many corners of the oven chamber main body 10 are fixed by inserting or fitting a metal plate. In such a place, since there is play between the metal plate members that come into contact with each other, even if the metal plate member expands and contracts due to heat, a large load is not applied to the fixed portion. As a result, it is possible to prevent cracks from occurring in the metal plate member.
In particular, during the temperature rise analysis, the temperature of the metal plate member facing the internal space 11 rises up to about 450 ° C., whereas the temperature of the outer metal plate member rises only up to about 150 ° C. .. Therefore, the temperature difference between the inner metal plate member and the outer metal plate member sandwiching the heat insulating material may become very large. Since the front frame metal plate member 106 is in contact with both the inner metal plate member and the outer metal plate member, there is a large difference in expansion and contraction due to temperature depending on the portion. The stress due to this expansion and contraction tends to be concentrated on the corners 1061 at the four inner corners of the front frame metal plate member 106, but in the oven of this embodiment, the corners 1061 have a substantially arcuate roundness and are inside the corners 1061. Is formed with an extension portion 1064 that bends at a substantially right angle. As a result, stress is less likely to be concentrated on the corner portion 1061, and the occurrence of cracks due to fatigue fracture can be reduced.

Further, in the oven of this embodiment, welding is not used for assembling the oven chamber main body 10, and the oven can be assembled by using a simple tool such as a screwdriver. When a welding process is required for manufacturing, it is costly to prepare welding equipment at the final assembly site. Therefore, a member manufactured by welding at a factory is usually transported to the final assembly site for assembly. However, in that case, since the outer size of the member is large, the cost required for transportation is large.
On the other hand, in the oven of the present embodiment, the main members constituting the oven chamber main body 10 are flat plate-shaped, L-shaped, or U-shaped metal plate members, which are larger in number than the box-shaped members. The members can be transported in the same volume. This also has the advantage that transportation costs can be reduced.

It should be noted that the above embodiment is merely an example of the present invention, and it is natural that the present invention is included in the claims even if it is appropriately modified, modified, added, etc. within the scope of the present invention.

10 ... Oven chamber main body 10a ... Right side wall part 10b ... Left side wall part 10c ... Top surface wall part 10d ... Bottom wall part 10e ... Back wall part 10f ... Front frame part 101 ... Inner first metal plate member 1011 ... Stacking part 1012 ... Insertion Port 102 ... Inner second metal plate member 1021 ... Convex piece portion 103 ... Outer first metal plate member 1031 ... Extension piece 1032 ... Insertion port 1033 ... Small hole 104 ... Outer metal foil member 105 ... Outer second metal plate member 106 ... Front frame Metal plate member 1061 ... Corner portion 1062 ... Convex piece portion 1063 ... Overlapping portion 1064 ... Extension portion 107 ... Metal plate member 11 ... Internal space 12 ... Door 1 ... Sample vaporization chamber 2 ... Carrier gas flow path 3 ... Injector 4 ... Gas chromatograph device main body 41 ... Housing 42 ... Operation unit 5 ... Capillary column 6 ... Detector

Claims (8)

An oven chamber main body having a substantially rectangular parallelepiped shape and an opening on the front surface and a door for opening and closing the front opening of the oven chamber main body are provided, and an internal space for accommodating a column is formed by the oven chamber main body and the door. In a gas chromatograph oven
The main body of the oven chamber is a metal plate member or a substantially flat plate in which the five wall surfaces of the right side, the left side, the bottom surface, the top surface, and the back surface, excluding the front surface, are bent into a substantially U-shape or a substantially L-shape. Formed using at least two metal plate members that are
At least one corner between two adjacent surfaces formed by abutting different metal plate members at a substantially right angle, the two metal plate members were connected by a method having a lower strength than welding. It is considered as a connection part for dissipation,
When the gas pressure in the internal space rises above a predetermined level, the emission connection portion is detached, broken, broken, or deformed to form an opening that functions as an explosion emission port .
The method having a lower strength than welding is a method of inserting a convex piece formed by bending one metal plate member at a substantially right angle into an insertion opening of the other metal plate member. .. An oven chamber main body having a substantially rectangular parallelepiped shape and an opening on the front surface and a door for opening and closing the front opening of the oven chamber main body are provided, and an internal space for accommodating a column is formed by the oven chamber main body and the door. In a gas chromatograph oven
The main body of the oven chamber is a metal plate member or a substantially flat plate in which the five wall surfaces of the right side, the left side, the bottom surface, the top surface, and the back surface, excluding the front surface, are bent into a substantially U-shape or a substantially L-shape. Formed using at least two metal plate members that are
At least one corner between two adjacent surfaces formed by abutting different metal plate members at a substantially right angle, the two metal plate members were connected by a method having a lower strength than welding. It is considered as a connection part for dissipation,
When the gas pressure in the internal space rises above a predetermined level, the emission connection portion is detached, broken, broken, or deformed to form an opening that functions as an explosion emission port .
An oven for a gas chromatograph characterized in that a method having a lower strength than welding is a method of screwing a convex piece formed by bending one metal plate member at a substantially right angle to the other metal plate member . The gas chromatograph oven according to claim 1 or 2 .
In the main body of the oven chamber, the right side surface, the left side surface, the bottom surface, the top surface, and the five wall surfaces on the back surface each have a three-layer structure in which a heat insulating material is sandwiched between an inner metal plate and an outer metal plate. , Right side, left side, bottom surface, and top surface, respectively, so as to close between the edge of the inner and outer metal plates facing the front, the metal plate member with a substantially frame shape is placed on the right side and left side. It is attached to the metal plate member forming the surface, bottom surface, and top surface, and the metal plate member having a substantially frame shape and the metal plate member forming the right side surface, left side surface, bottom surface, and top surface are substantially perpendicular to each other. An oven for a gas chromatograph , wherein a corner portion between two adjacent surfaces formed by abutting is used as the emission connecting portion. The gas chromatograph oven according to any one of claims 1 to 3 .
When the bent portion of the metal plate member bent into a substantially U-shape or a substantially L-shape is the corner portion, a perforated portion in which small holes are intermittently formed along the bent position is provided. A featured gas chromatograph oven. The gas chromatograph oven according to any one of claims 1 to 4 .
An oven for a gas chromatograph, characterized in that all corner portions other than the bent portion are used as the emission connecting portion. The gas chromatograph oven according to claim 5 .
Wherein at least a portion of said dissipating connecting portions, a gas chromatograph oven, characterized in that those which gave play between the two metal plate. The gas chromatograph oven according to claim 3 .
In the metal plate member having a substantially frame shape, the linear portions of the four sides facing inward are bent rearward at a substantially right angle, and the corner portion between the linear portions of any two adjacent sides is viewed from the front. An oven for a gas chromatograph, which has a substantially arc shape and is formed by drawing to extend pieces that are continuously connected to the bent portions of the straight portions on both sides thereof and extend to the rear side. The gas chromatograph oven according to any one of claims 1 to 7 , a column housed in the internal space of the oven, a sample introduction portion connected to an inlet end of the column, and an outlet end of the column. A gas chromatograph device comprising a detection unit connected to the oven.

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