JP4087696B2 - Microwave heating device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a microwave heating apparatus, and in particular, efficiently performs a heat treatment by irradiating an object to be heated accommodated in a high temperature and high pressure resistant container by efficiently supplying a microwave into the high temperature and high pressure resistant metal container. The present invention relates to a microwave heating apparatus.
[0002]
[Prior art]
In recent years, in the chemical field, attention has been paid to the fact that the microwave itself has an action of accelerating the catalytic reaction, and many papers have been published that a chemical reaction promoting effect can be obtained by using a familiar microwave oven. However, a chemical reaction promotion experiment using a microwave oven raises a problem that a reactor formed of quartz glass, Teflon (registered trademark), or the like was destroyed by an explosive reaction. In the background of such experiments, in general, the result is that the faster the chemical reaction is completed, the higher the purity of the reaction product is obtained. It is desirable to make the device capable of withstanding high temperature and high pressure resistance as much as possible. Research institutions such as universities do not need to produce reaction products in large quantities, and it is desired that the size of the portion to which high pressure is applied can be made as small as possible for safety reasons.
[0003]
Recently, there has been research on chemical reactions in a state called supercritical, which has attracted particular attention. For example, research has been published that, under conditions of temperatures of about 400 ° C. and about 30 MPa (300 atm), even neutral water that is stable at normal temperature and normal pressure becomes radical molecules and has a corrosive action. It is necessary to conduct basic research while maintaining such a state in a stable manner, and at present, no experimental research has been conducted so far.
[0004]
The tracking of the temperature change of the object to be heated corresponding to the increase / decrease of the microwave power is much faster than other heating methods, so it is superior to microwave heating especially to keep the temperature of the object to be heated constant. There is nothing. In order to obtain a supercritical state, there are a method using a combination with the conventional method and a method using only microwave heating, but the present invention does not stick to these methods. In addition, against this background, there has been a demand for the emergence of a microwave coupler that can withstand use at high temperatures and high pressure resistances and can efficiently introduce microwaves regardless of the size of a container that accommodates an object to be heated. Yes.
[0005]
On the other hand, in supercritical water experiments, microwave heating has attracted attention. For example, high-speed temperature control of an object to be heated by microwave irradiation in an experimental environment at a temperature of about 400 ° C. and about 30 MPa (300 atm). In addition, since a chemical reaction promoting effect can be expected, heating control of an object to be heated by microwave irradiation has attracted attention.
[0006]
As this kind of microwave supply device for promoting chemical reaction into a high temperature and high pressure vessel, for example, as shown in Patent Document 1 below, a first window is formed in a part of the pressure vessel, and a first outside the pressure vessel. High temperature and high pressure having a hollow waveguide or coaxial line in which the pressure vessel is sealed by two partition windows each having two windows, and the internal pressure between the first window and the second window can be controlled. A microwave supply device for promoting chemical reaction to a container is disclosed.
[0007]
Patent Document 2 below discloses a structure of a high-temperature and high-pressure vessel provided with a chemical reaction promoting microwave supply device having a single window by disposing the reaction vessel in a high-temperature and high-pressure vessel.
[0008]
[Patent Document 1]
JP 2002-113349 A
[Patent Document 2]
JP 2002-113350 A
[0009]
[Problems to be solved by the invention]
However, the microwave supply device for promoting chemical reaction to the high-temperature and high-pressure vessel constructed as described above has a relatively small-capacity high-temperature and high-pressure vessel configuration when using a commercially available microwave having a wavelength of about 2.45 GHz. It is difficult to introduce microwaves into the high-temperature and high-pressure vessel. That is, in the configuration of a high-capacity high-temperature and high-pressure vessel, a strong pressure-resistant structure is required. In addition, when connecting between the first window and the second window via a waveguide or a coaxial line for propagating microwaves, for example, when using a coaxial line, the micro window is placed in a high-temperature high-pressure vessel. Although waves could be introduced to some extent, there was a problem that they could not be supplied efficiently.
[0010]
On the other hand, since the waveguide is a kind of high-pass filter, a waveguide having a size less than a certain limit cannot be used. For example, in the case of a microwave having a wavelength of about 2.45 GHz, if the long side dimension of the rectangular cross section is ½ or less of the free space wavelength, that is, about 61.1 mm or less, it is theoretically impossible to propagate the microwave. In practice, as the critical dimension is approached, propagation loss in the inner wall surface portion of the waveguide increases rapidly, so a size of 70 mm to 110 mm is usually used. Therefore, since the structure of the power feeding portion is increased, a strong pressure-resistant structure is required.
[0011]
In addition, the structure of Patent Document 2 has a problem that it is difficult to reduce the size of the high-temperature and high-pressure vessel, as in Patent Document 1.
[0012]
Accordingly, the present invention has been made to solve the above-described conventional problems, and an object of the present invention is to provide a microwave heating apparatus capable of efficiently supplying microwaves into a high-temperature and high-pressure vessel from a small size to a large size. Is to provide.
[0013]
Another object of the present invention is to provide a microwave heating apparatus that can use a commercially available microwave power of a wavelength of about 2.45 GHz and can easily perform microwave heating of an object to be heated at low cost. There is to do.
[0014]
[Means for Solving the Problems]
In order to achieve such an object, a microwave heating apparatus according to the present invention includes a microwave generator that radiates microwaves, and a first inner conductor and a first outer conductor that propagate the microwaves on the same axis. And a coaxial line having an input end connected to the microwave output portion of the microwave generator and an output end for transmitting the microwave propagating through the inside, and a hollow portion for accommodating an object to be heated formed therein A sealed pressure-resistant metal container having an opening window formed in a part of the side wall, a central conductor made of a metallic member disposed in the cavity, and a second inner conductor for propagating the microwave And the second outer conductor on the same axis, and connected to the output end of the coaxial line, the input portion for introducing the microwave and the end portion of the second inner conductor are inserted into the insulator, and the microwave is In the pressure-resistant metal container A microwave coupler disposed in contact with the central conductor, having an output portion to be inserted, allowing the insulator to pass through the opening window, causing the terminal portion of the second inner conductor to protrude into the pressure-resistant metal container, and By providing, the microwave radiated from the microwave generator propagates in the first inner conductor and the first outer conductor of the coaxial line, and the second inner conductor and the second outer conductor of the microwave coupler. Each is introduced and propagated into the cavity, and is efficiently supplied into the cavity of the pressure-resistant metal container.
[0015]
Another microwave heating apparatus according to the present invention has a microwave generator for radiating microwaves, a first inner conductor and a first outer conductor for propagating the microwaves on the same axis, and a microwave. A coaxial line having an input end connected to the microwave output portion of the wave generator and an output end for transmitting the microwave propagating through the inside, a hollow portion for accommodating an object to be heated inside, and a side wall A hermetically sealed pressure-resistant metal container partially formed with an opening window, and a second inner conductor and a second outer conductor for propagating the microwave are coaxially coupled to the output end of the coaxial line. An input section for introducing the microwave and a terminal section of the second inner conductor through the insulator, and an output section for propagating the microwave into the pressure-resistant metal container. The insulator is inserted into the opening window. The end of the second inner conductor The microwave radiated from the microwave generator is provided on the first line of the coaxial line by providing a microwave coupler that protrudes into the conductive metal container and is disposed in contact with the inner wall facing the opening window. Propagates in the inner conductor and the first outer conductor, is introduced into the second inner conductor and the second outer conductor of the microwave coupler, propagates, and is efficiently supplied into the cavity of the pressure-resistant metal container. The
[0016]
Another microwave heating apparatus according to the present invention has a microwave generator for radiating microwaves, a first inner conductor and a first outer conductor for propagating the microwaves on the same axis, and a microwave. A coaxial line having an input end connected to the microwave output portion of the wave generator and an output end for transmitting the microwave propagating through the inside, a hollow portion for accommodating an object to be heated inside, and a side wall A sealed pressure-resistant metal container partially formed with an opening window, a central conductor made of a metallic member disposed in the cavity, a second inner conductor for propagating the microwave, and a second outer conductor The conductor is provided on the same axis and connected to the output end of the coaxial line. The input part for introducing the microwave and the terminal part of the second inner conductor are enclosed in an insulator, and the microwave is contained in the pressure-resistant metal container. Has an output part to propagate, The body is inserted into the opening window, the tip of the insulator is protruded into the pressure-resistant metal container, and a microwave coupler disposed close to the center conductor is provided, thereby being emitted from the microwave generator. The microwave propagates in the first inner conductor and the first outer conductor of the coaxial line, and is introduced and propagated in the second inner conductor and the second outer conductor of the microwave coupler, respectively. It is efficiently supplied into the cavity of the metal container.
[0017]
Another microwave heating apparatus according to the present invention has a microwave generator for radiating microwaves, a first inner conductor and a first outer conductor for propagating the microwaves on the same axis, and a microwave. A coaxial line having an input end connected to the microwave output portion of the wave generator and an output end for transmitting the microwave propagating through the inside, a hollow portion for accommodating an object to be heated inside, and a side wall A pressure-resistant metal container having an opening window formed in part, a second inner conductor and a second outer conductor for propagating the microwave on the same axis, and connected to the output end of the coaxial line. An input part for introducing a wave and a terminal part of the second inner conductor are included in an insulator, and an output part is provided for propagating the microwave into the pressure-resistant metal container. In the pressure-resistant metal container The microwave radiated from the microwave generator is provided with a microwave coupler disposed close to the inner wall facing the opening window and the first inner conductor of the coaxial line and the first , And introduced and propagated into the second inner conductor and the second outer conductor of the microwave coupler, respectively, and efficiently supplied into the cavity of the pressure-resistant metal container.
[0018]
Another microwave heating apparatus according to the present invention has a microwave generator for radiating microwaves, a first inner conductor and a first outer conductor for propagating the microwaves on the same axis, and a microwave. A coaxial line having an input end connected to the microwave output portion of the wave generating device and an output end for transmitting the microwave propagating through the inside, a hollow portion for accommodating an object to be heated, and an opening communicating with the hollow portion A pressure-resistant metal container having a window, a temperature sensor arranged by inserting the sensor portion through the opening window, and a second inner conductor and a second outer conductor for propagating the microwave are coaxially provided. And an input portion connected to the output end of the coaxial line and an output portion for propagating the microwave propagating through the inside through the insulator into the hollow portion, and having the second inner conductor The end part is the insulator. And a microwave coupler disposed so as to protrude through the hollow portion so that the microwaves emitted from the microwave generator can pass through the first inner conductor and the first outer conductor of the coaxial line. Are introduced into the second inner conductor and the second outer conductor of the microwave coupler, propagated, and efficiently supplied into the cavity of the pressure-resistant metal container.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIGS. 1A and 1B are sectional views of the concept shown for easy understanding of the configuration of an embodiment of the microwave heating apparatus according to the present invention. 1A and 1B, reference numeral 1 denotes a microwave coupler that introduces microwaves into a cavity 2a of a metal container 2 having a high temperature and high pressure resistance. The input part, 1b is the output part, and 1c is the inner conductor terminal part of the coaxial line.
[0020]
A coaxial line having an inner conductor and an outer conductor (not shown) coaxially connected to the input section 1a of the microwave coupler 1, and the microwave propagated in the inner conductor and the outer conductor of the coaxial line is output to the output section 1b. To the cavity 2a in the metal container 2. As a result, an object to be heated (not shown) accommodated in the cavity 2a is heated by microwave irradiation. Reference numeral 3 denotes an attachment screw for attaching and fixing the microwave coupler 1 to the metal container 2.
[0021]
In such a configuration, when the volume in the cavity 2a of the metal container 2 is relatively large, the microwave is supplied from the terminal end 1c of the output part 1b into the cavity 2a of the metal container 2, and the cavity 2a. The object can be radiated to an object to be heated (not shown) and heated by microwaves. Moreover, when the volume in the cavity 2a of the metal container 2 is relatively small, for example, as shown in FIG. 1A, even if the length of the metal container 2 in the Z-axis direction is sufficient, As shown in FIG. 1 (b), when the long side dimension H1 and the short side dimension H2 are less than or equal to one-half of the in-tube wavelength of the microwave propagating in the hollow portion 2a of the metal container 2. The microwave is not introduced from the terminal end 1c of the output unit 1b. That is, even if the object to be heated is accommodated in the cavity 2a, microwave heating is not performed at all.
[0022]
2A and 2B are cross-sectional views illustrating a configuration of an embodiment of the microwave heating apparatus according to the present invention, in which FIG. 2A is a vertical cross-sectional view, and FIG. It is sectional drawing of a line. In FIG. 2, reference numeral 1 denotes an input unit 1a to which microwave power is supplied, an output unit 1b for introducing a microwave into a metal container 2 having high temperature and high pressure resistance, and an input unit 1a and an output unit 1b. This is a microwave coupler having a coaxial tube coupled between them and having an inner conductor and an outer conductor inside, and an inner conductor terminal portion 1c provided so as to protrude from the tip of the output portion 1b.
[0023]
Although not shown, the microwave generator 1 that radiates microwave power of about 2.45 MHz that is normally used is coaxially provided on the input unit 1a of the microwave coupler 1 on the same axis as the first inner conductor and the second outer conductor. It is the structure connected through the external coaxial track | line which has.
[0024]
Reference numeral 2 denotes a metal container made of, for example, a nickel material as a metal material having high temperature and high pressure resistance, and having a cylindrical cavity 2a for accommodating an object to be heated therein. A cylindrical opening 2c is formed in the side wall 2b, and a microwave coupler 1 for introducing a microwave into the metal container 2 projects through the output part 1b and the inner conductor terminal part 1c into the opening 2c. And are firmly attached and fixed to the metal container 2 by means of attachment screws 3.
[0025]
In this case, in the opening 2c of the metal container 2, the output portion 1b of the microwave coupler 1 is electrically insulated, and an insulating portion made of, for example, quartz or ceramic that absorbs less microwaves is provided in the opening 2c. The tip portion 1c of the inner conductor inserted through the insulator of the output portion 1b is protruded and attached in an electrically insulated state.
[0026]
Reference numeral 4 denotes a central conductor formed in a cylindrical shape from a conductive metal material or the like. The central conductor 4 has its tip portion in a non-contact state with the ceiling in the metal container 2 and is welded to the substantially central portion of the bottom surface. It is fixedly arranged. The central conductor 4 has a structure in which the terminal end portion 1c of the inner conductor protruding from the output portion 1b of the microwave coupler 1 is in electrical contact.
[0027]
FIG. 3 is a cross-sectional view illustrating a detailed configuration of the microwave coupler 1 shown in FIG. 2, and FIG. 3 shows a structure for attaching to the metal container 2. The same parts as those in FIG. 2 described above are denoted by the same reference numerals, and the description thereof is omitted. In FIG. 3, reference numeral 10 denotes a substantially cylindrical metal structure having a flange portion 10a at the peripheral portion and a hollow portion formed therein, and this metal structure 10 is a metal material having high temperature and high pressure resistance, such as nickel. It is formed from materials. Further, the hollow portion formed inside the metal structure 10 is made of, for example, quartz or ceramic material having high electrical insulation and low microwave absorption, and a through hole is formed along the central axis direction. The thick-walled cylindrical insulator 11 is inserted with a plurality of O-rings 12 interposed.
[0028]
Further, a metal lead 13 for introducing a microwave into the metal container 2 is inserted into the through hole formed along the central axis direction of the insulator 11, and the terminal portion 13a has a thick wire diameter. Formed and protruded into the metal container 2, and a plurality of O-rings 14 are interposed between the terminal end portion 13 a and the insulator 11, and the input end portion 13 b is on the other end side of the insulator 11. It is fastened and fixed by a mounting nut 15. As a result, the end portion 13a of the metal lead 13 and the insulator 11 are hermetically maintained.
[0029]
Although not shown, a metal cylinder 16 connected to an outer conductor of an external coaxial line coupled to the microwave generator is fixedly disposed on the end surface of the cylindrical metal structure 10 by a mounting screw 17. . The input end 13b of the metal lead 13 and the metal cylindrical body 16 are connected to the inner conductor and the outer conductor of the external coaxial line connected to a microwave generator (not shown), and are coupled at a high frequency. ing.
[0030]
The microwave coupler 1 configured as described above projects a terminal portion 13a for introducing a microwave into an opening 2c formed in the side wall 2b of the metal container 2 shown in FIG. A plurality of O-rings 18 are interposed between the structure 10 and the tip of the insulator 11 is inserted, and the mounting screw 3 is firmly attached and sealed and fixed. Here, the terminal end 13a corresponds to the terminal end 1c shown in FIG. As a result, the opening 2c of the metal container 2 and the metal structure 10 are hermetically held, and the O-ring 18 interposed between the insulator 11 and the metal structure 10 is tightened to tighten the insulator 11 and the metal structure. Thus, the metal container 2 and the microwave coupler 1 are coupled to each other both at high frequency and at high pressure. Accordingly, the pressure in the metal container 2 is maintained at a high pressure.
[0031]
In the microwave heating apparatus configured as described above, when performing an experiment, first, the microwave coupler 1 attached to the metal container 2 is first removed from the cavity 2 of the metal container 2 through the opening 2c by removing the plurality of mounting screws 3. A required object to be heated is accommodated in the part 2a. Thereafter, the plurality of attachment screws 3 are firmly attached and fixed again to hold the inside of the metal container 2 in a sealed state.
[0032]
In the microwave coupler 1, the input end portion 13b of the metal lead 13 and the metal cylindrical body 16 are respectively connected to the inner conductor and the outer conductor of an external coaxial line connected to a microwave generator (not shown). Therefore, the microwave propagated to the external coaxial line is introduced into the microwave coupler 1 without any problem.
[0033]
That is, the cylindrical metal structure 10 constituting the microwave coupler 1, the metal cylinder 16 connected to the metal structure 10, and the side wall 2b correspond to the second outer conductor of the coaxial line, and the metal lead 13 is the second. Therefore, the microwave propagated in the microwave coupler 1 is introduced into the metal container 2.
[0034]
As shown in FIG. 2, the end portion 13 a of the metal lead 13 corresponding to the output portion 1 b of the microwave coupler 1 is in contact with the front end portion of the center conductor 4 disposed in the metal container 2. Therefore, the microwave is coupled and propagated to the central conductor 4, and the microwave is supplied to a narrower portion in the cavity 2 a of the metal container 2, so that the object to be heated accommodated in the cavity 2 a is irradiated. And can be efficiently heated by microwaves.
[0035]
FIG. 4 is a cross-sectional view of an essential part for explaining the configuration of another embodiment of the microwave heating apparatus according to the present invention. The same parts as those in FIG. 4 is different from FIG. 2 in that the microwave coupler 1 is attached in contact with the end portion 1c of the output portion 1b in the same direction as the length direction of the central conductor 4 disposed in the metal container 2. It is fixed. Even in such a configuration, the same effect as described above can be obtained.
[0036]
FIG. 5 is a cross-sectional view of an essential part for explaining the configuration of still another embodiment of the microwave heating apparatus according to the present invention. The same parts as those in FIG. 5 is different from FIG. 2 in that the metal container 2A is formed to have a small volume cavity 2a, and the microwave coupler 1 is opposed to the terminal part 1c of the output part 1b of the metal container 2A. It is attached and fixed in contact with the wall surface 2d. In this configuration, the central conductor 4 shown in FIG. 2 is not disposed in the metal container 2A.
[0037]
In such a configuration, even if the central conductor 4 is not required in the metal container 2, microwaves are supplied into the narrow cavity 2a of the metal container 2, and the object to be heated accommodated in the cavity 2a Since it is irradiated, microwave heating can be performed efficiently.
[0038]
FIG. 6 is a cross-sectional view of an essential part for explaining the configuration of another embodiment of the microwave heating apparatus according to the present invention. The same parts as those in FIG. 6 differs from FIG. 2 in that a microwave coupler 1A is attached and fixed to the tip of a central conductor 4 disposed in the metal container 2 with its output portion 1b in proximity.
[0039]
FIG. 7 is a cross-sectional view showing a detailed configuration of the microwave coupler 1A shown in FIG. 6, and FIG. In addition, the same code | symbol is attached | subjected to the same part as FIG. 3 mentioned above, and the description is abbreviate | omitted. 7 is different from FIG. 3 in that the tip 11a of the insulator 11 constituting the output portion 1b of the microwave coupler 1A is disposed so as to protrude into the metal container 2, and the insulator 11 Has a structure in which the end portion 13a of the metal lead 13 as the second inner conductor is included and is not exposed in the metal container 2.
[0040]
Further, since the end portion 13a of the metal lead 13 is formed with the same dimension as the wire diameter of the main body of the metal lead 13, it is inserted into the insertion hole 11b formed along the central axis of the insulator 11 and fixed. The structure is arranged. Therefore, the mounting nut 15 shown in FIG. 3 for fixing to the insulator 11 is unnecessary. Further, a plurality of airtight fixing O-rings 18 are interposed between the peripheral edge of the opening 2c of the metal container 2 and the insulator 11, so that the metal container 2 and the microwave coupler 1A are hermetically held.
[0041]
In such a configuration, the microwave propagated to the metal lead 13 is transmitted through the inside of the tip end portion 11a of the insulator 11 without absorbing the microwave, and the center in the metal container 2 shown in FIG. Since it is coupled to the conductor 4 and supplied to the narrow cavity 2a and irradiated to the object to be heated accommodated in the cavity 2a, microwave heating can be performed efficiently.
[0042]
According to such a configuration, the terminal end portion 13 a of the metal lead 13 is covered with the tip end portion 11 a of the insulator 11, so that it is isolated from the object to be heated housed in the metal container 2. Therefore, even if a highly corrosive liquid is contained as an object to be heated, the metal lead 13 and its terminal end portion 13a are not chemically affected. The material can be used.
[0043]
FIG. 8 is a cross-sectional view showing a configuration of another microwave coupler according to another embodiment, and FIG. 8 shows a structure for mounting to a high pressure vessel. The same parts as those in FIG. 7 described above are denoted by the same reference numerals, and description thereof is omitted. 8 differs from FIG. 7 in that a plurality of O-rings 18 for airtight fixing are interposed between the peripheral edge of the opening 2c of the high pressure resistant container 2 and the metal structure 10, and the mounting screws 3 are firmly attached and hermetically fixed. By doing so, the space between the metal container 2 and the microwave coupler 1B is hermetically held, and the rest of the configuration is exactly the same as in FIG. Even if the microwave coupler 1B configured as described above is used, the same effect as described above can be obtained.
[0044]
FIG. 9 is a cross-sectional view of an essential part for explaining the configuration of another embodiment of the microwave heating apparatus according to the present invention. The same parts as those in FIG. 9 is different from FIG. 6 in that the center conductor 4 is fixedly disposed between the ceiling and the bottom surface by welding or the like at the center inside the metal container 2. In addition, a microwave coupler 1A is attached and fixed to the metal container 2 with its output portion 1b (a portion corresponding to the tip portion 11a of the insulator 11 shown in FIGS. 7 and 8) close to the center conductor 4. ing.
[0045]
In such a configuration, the microwave propagated in the microwave coupler 1A is coupled to the center conductor 4 through the output portion 1b, and reaches the narrower cavity portion in the cavity portion 2a of the metal container 2. Is propagated and introduced. Therefore, the object to be heated accommodated in the cavity 2a of the metal container 2 can be efficiently heated by microwaves. Needless to say, the same effect can be obtained by applying the microwave coupler 1B shown in FIG. 8 instead of the microwave coupler 1A used in the present embodiment.
[0046]
FIG. 10 is a cross-sectional view of an essential part for explaining the configuration of another embodiment of the microwave heating apparatus according to the present invention. The same parts as those in FIG. 10 is different from FIG. 4 in that the microwave coupler 1A brings the output portion 1b (a portion corresponding to the tip portion 11a of the insulator 11 shown in FIGS. 7 and 8) close to the tip portion of the central conductor 4. Let it be fixed. Even in such a configuration, the same effects as those described with reference to FIG. 4 can be obtained. It goes without saying that the same effect can be obtained even if the microwave coupler 1B shown in FIG. 8 is applied instead of the microwave coupler 1A used in this embodiment.
[0047]
FIG. 11 is a cross-sectional view of an essential part for explaining the configuration of another embodiment of the microwave heating apparatus according to the present invention. The same parts as those in FIG. 11 is different from FIG. 5 in that the microwave coupler 1A corresponds to the output portion 1b (the front end portion 11a of the insulator 11 shown in FIGS. 7 and 8) on the inner wall surface facing the wall surface attached to the metal container 2A. Are attached and fixed close to each other.
[0048]
According to such a configuration, since the output portion 1b of the microwave coupler 1A is isolated from the object to be heated contained in the cavity 2a of the metal container 2, a highly corrosive liquid or the like is used as the object to be heated. Even if the metal lead 13 is accommodated, the metal lead 13 contained in the insulator 11 and the terminal end portion 13a thereof are not corroded, so that it is possible to use a material to be heated that is inexpensive and highly available. In addition, since the metal container 2A can be made compact by a configuration that eliminates the need for the central conductor in the metal container 2A, a small-volume microwave heating device can be realized. Needless to say, the same effect can be obtained by applying the microwave coupler 1B shown in FIG. 8 instead of the microwave coupler 1A used in the present embodiment.
[0049]
FIG. 12 is a cross-sectional view of an essential part for explaining the configuration of still another embodiment of the microwave heating apparatus according to the present invention. In FIG. 12, 20 is made of, for example, nickel as a metal material having high temperature and high pressure resistance, and a heating chamber 20a and a sensor window 20b having a concave cross section for accommodating an object to be heated are formed in the central portion inside. Pressure chamber. Further, in the pressure chamber 20, a temperature sensor 21 with a sensor portion 21a exposed is inserted into a sensor window 20b with a packing 22 interposed therebetween.
[0050]
In addition, a thick-walled cylindrical insulator 23 made of, for example, alumina ceramic, which is an insulator that allows microwaves to pass through efficiently, and having a through hole 23a formed in the central axis direction is disposed above the pressure chamber 20. Furthermore, the upper portion of the insulator 23 is made of, for example, nickel as a metal material having high temperature and high pressure resistance, and has a cylindrical coaxial shape in which an opening 24a is formed at the center and a flange portion 24b is formed at the periphery. A tube support 24 is disposed so as to cover the cylindrical insulator 23, and is firmly tightened to the pressure chamber 20 by a plurality of bolts 27 and nuts 28 at the flange portion 24 b with the O-rings 25 and 26 interposed therebetween. It is hermetically sealed. In this case, the insulator 23 and the coaxial tube support 24 have a structure in which a through hole 23a and an opening 24a are coaxially arranged.
[0051]
The coaxial pipe support 24 has a coaxial pipe 31 having a cylindrical inner conductor 29 as a second inner conductor for propagating microwaves in the pressure chamber 20 and a cylindrical outer conductor 30 as a second outer conductor. The flange portion is fixed by a plurality of mounting screws 32. Further, the coaxial inner conductor 29 is formed such that the terminal portion 29 a extends into the heating chamber 20 a formed in the pressure chamber 20, thereby constituting the microwave coupler 33.
[0052]
The coaxial pipe 31 includes an outer coaxial line 34 having coaxially an inner conductor 34a as a first inner conductor for introducing a microwave from the outside and an outer conductor 34b as a second outer conductor on both flange portions. The microwave power connected to the output of the microwave generator connected to the bolt 35 and the nut 36 and generating a microwave power having a wavelength of about 2.45 GHz (not shown) and introduced into the external coaxial line 34 is a coaxial tube. The structure is such that it is propagated and introduced into 31 and supplied into the microwave coupler 33.
[0053]
In the microwave heating apparatus configured as described above, the microwaves propagating in the external coaxial line 34 are respectively propagated and introduced into the coaxial pipe inner conductor 29 and the coaxial pipe outer conductor 30 in the coaxial pipe 31 to be coaxial. The microwave propagated in the in-tube conductor 29 is supplied from the end portion 29a into the heating chamber 20a having a small volume, while the microwave propagated in the coaxial outer conductor 30 passes through the insulator 23, It is supplied into the heating chamber 20a having a small volume. Therefore, the object to be heated accommodated in the heating chamber 20a is irradiated and can be efficiently microwave-heated.
[0054]
Further, in such a configuration, by providing the temperature sensor window 20b in the heating chamber 20a, the sensor unit 21a of the temperature sensor 21 is brought into direct contact with an object to be heated accommodated in the heating chamber 20a. Various aspects can be observed such as the temperature rise of the object to be heated and the reaction status.
[0055]
According to such a configuration, the pressure chamber 20 can be configured in a small size, and a small volume type high pressure vessel can be realized. Further, since the terminal end portion 29a of the coaxial pipe inner conductor 29 is arranged in the sensor window 20b in the pressure chamber 20, it is isolated from the object to be heated accommodated in the heating chamber 20a. Therefore, even if a highly corrosive liquid or the like is accommodated as an object to be heated, the terminal portion 29a of the coaxial pipe inner conductor 29 is not corroded. Methanol or methane can be used.
[0056]
In the above-described embodiments, the microwave heating apparatus for supplying microwaves to a cylindrical high-temperature high-pressure vessel having a relatively small cross-sectional area and long and heating the object to be heated has been described. Needless to say, the present invention is not limited to these structures, and the same effects as described above can be obtained even when applied as a chemical reaction apparatus in a supercritical environment.
[0057]
【The invention's effect】
As described above, according to the microwave heating apparatus of the present invention, the microwave can be efficiently supplied into the cavity of the pressure-resistant metal container, and the object to be heated can be easily and efficiently microwave-heated. It is possible to standardize a coaxial power feeding structure that feeds microwaves into the container, and to obtain various excellent pressure resistant metal container structures regardless of the internal volume from small to large.
[0058]
Moreover, according to the microwave heating apparatus of the present invention, microwave heating of an object to be heated can be performed easily and efficiently using a commercially available microwave power having a wavelength of about 2.45 GHz. An extremely excellent effect is obtained such that a wave supply pressure resistant metal container can be provided at low cost.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of an essential part of a concept shown for facilitating understanding of a configuration according to an embodiment of a microwave heating apparatus according to the present invention.
FIG. 2 is a cross-sectional view of an essential part showing the configuration of an embodiment of a microwave heating apparatus according to the present invention.
3 is a cross-sectional view showing a configuration of a microwave coupler applied to the microwave heating apparatus shown in FIG.
FIG. 4 is a cross-sectional view of a main part showing a configuration of another embodiment of the microwave heating apparatus according to the present invention.
FIG. 5 is a cross-sectional view of the main part showing the configuration of another embodiment of the microwave heating apparatus according to the present invention.
FIG. 6 is a cross-sectional view of the main part showing the configuration of another embodiment of the microwave heating apparatus according to the present invention.
FIG. 7 is a cross-sectional view showing a configuration of another embodiment of a microwave coupler applied to the microwave heating device according to the present invention.
FIG. 8 is a cross-sectional view showing a configuration of still another embodiment of a microwave coupler applied to the microwave heating apparatus according to the present invention.
FIG. 9 is a cross-sectional view of a main part showing the configuration of another embodiment of the microwave heating apparatus according to the present invention.
FIG. 10 is a cross-sectional view of a main part showing the configuration of another embodiment of the microwave heating apparatus according to the present invention.
FIG. 11 is a cross-sectional view of the main part showing the configuration of another embodiment of the microwave heating apparatus according to the present invention.
FIG. 12 is a cross-sectional view showing a configuration of still another embodiment of the microwave heating apparatus according to the present invention.
[Explanation of symbols]
1 Microwave coupler
1A microwave coupler
1B microwave coupler
1a Input section
1b Output section
1c Terminator
2 Metal container
2a Cavity
2b side wall
2c opening
2d facing wall
3 mounting screws
4 Center conductor
10 Metal structure
10a Flange
11 Insulator
11a Tip
11b Insertion hole
12 O-ring
13 Metal lead
13a Termination
13b Input end
14 O-ring
15 nuts
16 Metal cylinder
17 Mounting screws
18 O-ring
20 Pressure chamber
20a Heating chamber
20b Sensor window
21 Temperature sensor
21a Sensor part
22 Packing
23 insulator
23a Through hole
24 Coaxial tube support
24a opening
25 O-ring
26 O-ring
27 volts
28 nuts
29 Coaxial pipe inner conductor
29a Termination
30 Coaxial pipe outer conductor
31 Coaxial pipe
32 screws
33 Microwave coupler
34 External coaxial line
34a Inner conductor
34b Outer conductor
35 volts
36 nuts

Claims (5)

A microwave generator that emits microwaves;
The microwave which has the 1st inner conductor and the 1st outer conductor which propagate the microwave on the same axis, is connected to the microwave output part of the microwave generator, and the microwave which propagates the inside A coaxial line having an output end for transmission;
A sealed pressure-resistant metal container in which a cavity for containing an object to be heated is formed, and an opening window is formed in a part of the side wall;
A central conductor made of a metallic member disposed in the cavity,
The second inner conductor and the second outer conductor for propagating the microwave are coaxially connected to each other and connected to the output end of the coaxial line to introduce the microwave and the second inner conductor. An output portion for inserting the end portion into the insulator and propagating the microwave into the pressure-resistant metal container; inserting the insulator into the opening window; and connecting the end portion of the second inner conductor to the opening portion. A microwave coupler that protrudes into the pressure-resistant metal container and is disposed in contact with the central conductor;
A microwave heating apparatus comprising: A microwave generator that emits microwaves;
The microwave which has the 1st inner conductor and the 1st outer conductor which propagate the microwave on the same axis, is connected to the microwave output part of the microwave generator, and the microwave which propagates the inside A coaxial line having an output end for transmission;
A sealed pressure-resistant metal container in which a cavity for containing an object to be heated is formed, and an opening window is formed in a part of the side wall;
The second inner conductor and the second outer conductor for propagating the microwave are coaxially connected, and are coupled to the output end of the coaxial line to introduce the microwave and the second inner conductor. An output portion for inserting the end portion through an insulator and propagating the microwave into the pressure-resistant metal container; passing the insulator through the opening window; and connecting the end portion of the second inner conductor to the opening portion. A microwave coupler that protrudes into the pressure-resistant metal container and is disposed in contact with the inner wall surface facing the opening window;
A microwave heating apparatus comprising: A microwave generator that emits microwaves;
The microwave which has the 1st inner conductor and the 1st outer conductor which propagate the microwave on the same axis, is connected to the microwave output part of the microwave generator, and the microwave which propagates the inside A coaxial line having an output end for transmission;
A sealed pressure-resistant metal container in which a cavity for containing an object to be heated is formed, and an opening window is formed in a part of the side wall;
A central conductor made of a metallic member disposed in the cavity,
The second inner conductor and the second outer conductor for propagating the microwave are coaxially connected to each other and connected to the output end of the coaxial line to introduce the microwave and the second inner conductor. An output part for enclosing the terminal part in an insulator and propagating the microwave into the pressure-resistant metal container; inserting the insulator through the opening window; and connecting the tip of the insulator to the pressure-resistant metal container A microwave coupler disposed in close proximity to the central conductor,
A microwave heating apparatus comprising: A microwave generator that emits microwaves;
The microwave which has the 1st inner conductor and the 1st outer conductor which propagate the microwave on the same axis, is connected to the microwave output part of the microwave generator, and the microwave which propagates the inside A coaxial line having an output end for transmission;
A pressure-resistant metal container in which a cavity for accommodating an object to be heated is formed and an opening window is formed in a part of the side wall;
A second inner conductor and a second outer conductor for propagating microwaves are coaxially provided, and are connected to an output end of the coaxial line to introduce the microwave and a terminal of the second inner conductor Including an output part for enclosing the part in an insulator and propagating the microwave into the pressure-resistant metal container, inserting the insulator through the opening window, and connecting the tip of the insulator to the pressure-resistant metal container And a microwave coupler disposed close to the inner wall facing the opening window,
A microwave heating apparatus comprising: A microwave generator that emits microwaves;
The microwave which has the 1st inner conductor and the 1st outer conductor which propagate the microwave on the same axis, is connected to the microwave output part of the microwave generator, and the microwave which propagates the inside A coaxial line having an output end for transmission;
A pressure-resistant metal container in which a hollow portion containing an object to be heated and an opening window communicating with the hollow portion are formed;
A temperature sensor disposed by inserting a sensor portion through the opening window;
The microwave which has the 2nd inner conductor and the 2nd outer conductor which propagate the microwave on the same axis, and is connected to the output end of the coaxial line, and the microwave which propagated the inside A microwave coupler having an output portion that propagates through the insulator into the cavity portion, and a terminal portion of the second inner conductor is disposed so as to penetrate the insulator and protrude into the cavity portion When,
A microwave heating apparatus comprising:

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