JP2003314265A - Heat retaining and radiating device and exhaust system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a heat retaining and radiating device and exhaust system parts which restrain overheating by exerting a heat insulating property and heat retaining property until a predetermined temperature region, and exerting radiating property when the temperature rises over the region. <P>SOLUTION: A catalytic converter 1 for purifying exhaust gas as an exhaust system is provided with a gas inlet port 10 into which exhaust gas flows, a gas outlet port 12 into which exhaust gas flows, and a gas passage 13 connecting the gas inlet port 10 and the gas outlet port 12. A vacuum insulating chamber 6 which is in vacuum state or at reduced pressure is provided on the upstream side of a catalyst 2. A volatile material 62 for lowering heat-insulating property of the vacuum insulating chamber 6 by vaporizing as temperatures rises, and increasing radiating property is enclosed in the vacuum insulating chamber 6. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat retaining / radiating device and an exhaust system component.

[0002]

2. Description of the Related Art A conventional technique will be described by taking an exhaust gas purifying catalytic converter as an example. An exhaust gas purifying catalytic converter equipped with a catalyst for purifying exhaust gas discharged from an engine such as an internal combustion engine has a gas inlet into which the exhaust gas flows, a gas outlet from which the exhaust gas flows out, a gas inlet and a gas. A gas flow path connecting the outlets and a catalyst storage chamber that is disposed in the gas flow path and stores a catalyst for purifying exhaust gas are provided. The exhaust gas flowing in from the gas inlet passes through the catalyst in the catalyst housing chamber, is purified by the catalyst, and flows out from the gas outlet. Exhaust gas purifying ability of the catalyst is good when it exceeds the activation temperature range, but exhaust gas purifying ability is not always sufficient when it is below the activation temperature range.

By the way, in driving a vehicle or the like, the internal combustion engine being driven is often stopped and then restarted. In this case, since the temperature of the catalyst is often lower than the activation temperature range, the catalyst is often below the activation temperature range immediately after the internal combustion engine is restarted, and the exhaust gas purification ability of the catalyst is reduced. Is not always enough. However, in recent years, there has been a strong demand for further improvement of the exhaust gas purifying ability of the catalyst even immediately after the internal combustion engine is restarted, in order to strengthen environmental protection.

Therefore, Japanese Patent Laid-Open No. 11-117731 discloses that a gas inlet into which exhaust gas flows, a gas outlet from which exhaust gas flows out, a gas passage connecting the gas inlet and the gas outlet, and a gas passage are arranged. There is disclosed an exhaust gas purifying catalytic converter including a catalyst accommodating chamber for accommodating an exhaust gas purifying catalyst. Between the gas inlet and the catalyst storage chamber,
An inorganic heat insulating material is provided by a metal net.

[0005]

However, according to the technique disclosed in Japanese Unexamined Patent Application Publication No. 11-117731, the heat insulating property is secured by the inorganic heat insulating material, but only the heat insulating property is achieved and the temperature rise is increased. It was not possible to expect heat dissipation when it became excessive. Therefore, the catalyst may be overheated depending on the temperature of the exhaust gas.

The present invention has been made in view of the above-mentioned circumstances, and exhibits heat insulation and heat retention up to a predetermined temperature region, and when the temperature is further raised, heat radiation is exerted to suppress overheating. It is an object of the present invention to provide a heat retaining / radiating device and an exhaust system component that can be used.

[0007]

According to a first aspect of the present invention, there is provided a heat retaining and radiating device, which includes a holding portion for holding an object whose temperature rises due to heating or heat generation, and a vacuum attached to the holding portion so as to enhance heat insulation of the object. And a vaporized substance that is sealed in the vacuum heat insulating chamber and that is vaporized with a temperature rise to reduce the heat insulating property of the vacuum heat insulating chamber and enhance the heat radiation property. It is what

When the temperature of the object is low, vaporization of the vaporizable substance has not progressed, and the degree of vacuum or the degree of reduced pressure of the vacuum heat insulating chamber is high. Therefore, the heat insulating property of the vacuum heat insulating chamber with respect to the object is high. On the other hand, when the temperature of the object rises,
Since the vacuum insulation chamber becomes hot, the vaporization of the vaporizable substance is progressing, and the heat transfer and heat dissipation properties of the vacuum insulation chamber are improved,
Excessive heat of the object can be released to the outside through the vacuum heat insulating chamber, and overheating of the object can be suppressed. Further, when the temperature of the object is lowered, the temperature of the vaporizable substance is also lowered, so that the vaporizable substance that has been vaporized in the vacuum heat insulating chamber progresses to be liquefied or solidified, and the degree of vacuum or the degree of reduced pressure in the vacuum heat insulating chamber is increased. In this case, since the heat insulating property and the heat retaining property of the vacuum heat insulating chamber are improved, the heat retaining property for the target object is improved, and the temperature reduction of the target object is suppressed.

An exhaust system component according to a second aspect of the present invention comprises a gas inlet through which exhaust gas flows, a gas outlet through which exhaust gas flows out,
In an exhaust system component including a gas passage connecting the gas inlet and the gas outlet, a heat insulating property for at least one of the gas inlet, the gas outlet, and the gas passage is set in a vacuum state or a reduced pressure state. It is characterized by comprising a vacuum heat insulating chamber and a vaporizable substance which is enclosed in the vacuum heat insulating chamber and is vaporized with a temperature rise to reduce the heat insulating property of the vacuum heat insulating chamber and to enhance the heat radiation property.

When the temperature of the exhaust system component is low, vaporization of the vaporizable substance is not progressing, and the degree of vacuum or decompression of the vacuum insulation chamber is high. Therefore, the heat insulation of the vacuum insulation chamber to the exhaust system component is high. . On the other hand, when the temperature of the exhaust system components rises, the temperature of the vacuum heat insulating chamber becomes high, so vaporization of the vaporizable substance in the vacuum heat insulating chamber is progressing, and the heat transfer and heat dissipation of the vacuum heat insulating chamber are improved. Excessive heat of the exhaust system parts can be released through the vacuum insulation chamber, and overheating of the exhaust system parts can be suppressed. Further, when the temperature of the exhaust system parts is lowered, the temperature of the vaporizable substance is also lowered, so that the vaporizable substance that has been vaporized in the vacuum heat insulating chamber progresses to be liquefied or solidified, and the degree of vacuum or the degree of pressure reduction of the vacuum heat insulating chamber is increased. In this case, since the heat insulation and heat retention of the vacuum heat insulation chamber are improved,
The temperature drop of the exhaust system parts is suppressed.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION
Preferably, a holding portion for holding an object whose temperature rises due to heating or heat generation from the outside, a vacuum heat insulation chamber attached to the holding portion and in a vacuum state or a decompressed state in order to enhance the heat insulating property to the object, a vacuum It may have a vaporizable substance enclosed in an adiabatic chamber and having a boiling point of 550 to 1150 ° C. under atmospheric pressure. The boiling point of the vaporizable substance under atmospheric pressure may be 600 to 900 ° C., particularly 650 to 750 ° C., but is not limited thereto.
In the present specification, the temperature of the boiling point means the temperature of the boiling point under the atmospheric pressure in consideration of the ease of confirming the temperature. Similarly, the solidification start temperature means the solidification start temperature under atmospheric pressure.

When the temperature of the object rises, the temperature of the vacuum heat insulating chamber becomes high, so vaporization of the vaporizable substance in the vacuum heat insulating chamber is progressing, and the heat transfer and heat dissipation of the vacuum heat insulating chamber are improved.
Excessive heat of the object can be released through the vacuum insulation chamber, and overheating of the object can be suppressed. On the other hand, when the temperature of the object is lowered, the temperature of the vaporizable substance is also lowered, so that the vaporized substance that has been vaporized in the vacuum insulation chamber progresses to be liquefied or solidified, and the degree of vacuum or reduced pressure in the vacuum insulation chamber increases. . In this case, the heat insulating property and heat retaining property of the vacuum heat insulating chamber are improved, so that the temperature reduction of the object is suppressed. Further, when the temperature of the object is lowered, the liquefied or solidified vaporizable substance that has been vaporized in the vacuum insulation chamber progresses, and latent heat is released from the vaporizable substance to the outside, so that the temperature of the object is further suppressed.

The exhaust system component according to the second aspect of the present invention preferably comprises a gas inlet into which exhaust gas flows, a gas outlet from which exhaust gas flows out, and a gas flow path connecting the gas inlet and the gas outlet. In the parts, a vacuum heat insulating chamber which is placed in a vacuum state or a reduced pressure state to enhance heat insulating properties to at least one of a gas inlet, a gas outlet, and a gas flow path, and a boiling point of 550 to 1150 at atmospheric pressure which is enclosed in the vacuum heat insulating chamber.
C. vaporizable material.

Examples of the exhaust system components include an exhaust gas purifying catalytic converter having a catalyst accommodating chamber for accommodating an exhaust gas purifying catalyst, an exhaust manifold for flowing exhaust gas from an internal combustion engine, and the like. In the case of a catalytic converter, the vacuum heat insulating chamber may be arranged on at least one of the upstream side of the catalyst, the downstream side of the catalyst, and the outer peripheral side of the catalyst. Furthermore, the gas flow path has an inclined wall whose flow passage area increases from the gas inlet toward the catalyst storage chamber, and the vacuum heat insulating chamber is arranged on at least a part of the inclined wall. You can

When the temperature of the catalyst rises, the temperature of the vacuum heat insulating chamber becomes high, so that the vaporizable substance in the vacuum heat insulating chamber is being vaporized, the heat transfer property and the heat radiating property of the vacuum heat insulating chamber are improved, and the excess of the catalyst is caused. The heat can be released through the vacuum insulation chamber, the overheating of the catalyst can be suppressed, and the durability of the catalyst can be maintained for a long time. On the other hand, when the catalyst cools and cools down, the temperature of the vaporizable substance drops, so the liquefaction or solidification of the vaporizable substance that has been vaporized in the vacuum insulation chamber progresses, and the degree of vacuum or decompression in the vacuum insulation chamber becomes high. Become. In this case, since the heat insulating property and heat retaining property of the vacuum heat insulating chamber are improved, the temperature drop of the catalyst is suppressed, and the catalyst can be kept in the activation temperature region for a long time. When the temperature of the catalyst further decreases,
Liquefaction or solidification of the vaporizable substance that has been vaporized in the vacuum heat insulating chamber progresses, and latent heat is released to the outside, so that the temperature drop of the catalyst is further suppressed. Therefore, the catalyst can be kept in the activation temperature region for as long as possible.

According to the heat retention and heat dissipation device and the exhaust system component of the present invention, a metal system can be adopted as the vaporizable substance, and specifically, zinc, zinc alloy, cadmium, cadmium alloy, selenium, A form formed of at least one selected from selenium alloy, magnesium, and magnesium alloy can be adopted. The vaporizable substance can be vaporized even in a temperature range lower than the boiling point. References (Tokyo Kagaku Dojin, Chemical Dictionary, No. 1
Edition 1st edition, issued October 1, 1994, p. 4 (zinc), p. 766 (selenium), p. 1388 (magnesium), p. 279 (cadmium)). Has a boiling point of 907 ° C., selenium has a boiling point of 684.6 ° C., and magnesium has a boiling point of 110.
The boiling point of cadmium is 765 ° C. The boiling point can also be adjusted by forming a vaporizable substance with an alloy in which a plurality of elements coexist.

According to the heat retention / radiation device and the exhaust system component of the present invention, it is possible to adopt a mode in which the heat storage member is provided adjacent to the vacuum heat insulating chamber. When the heat storage member is provided in this way, the heat retaining property for the object, the exhaust system component, and the catalyst is further enhanced. When the heat storage member is provided adjacent to the vacuum heat insulating chamber as described above, the heat of the heat storage member is satisfactorily transferred to the vacuum heat insulating chamber when the vacuum heat insulating chamber exhibits heat transfer and heat dissipation properties. The overheating of can be suppressed. Further, when the vacuum heat insulating chamber exhibits heat insulating properties and heat retaining properties, it is possible to suppress the temperature drop of the heat storage member.

The heat storage member accumulates as latent heat as the temperature rises and releases the heat accumulated as latent heat as the temperature falls. The above-mentioned heat storage member can be made of a metal-based material, and a form in which at least one of magnesium, aluminum, tin, antimony, zinc, and lithium is a main component can be adopted. Specifically, magnesium, magnesium-zinc based alloy, magnesium-zinc-aluminum based alloy, magnesium-aluminum based alloy, tin, tin-zinc based alloy, magnesium-
Formed of at least one metal selected from tin-based alloys, aluminum, aluminum-tin-based alloys, antimony, antimony-tin-based alloys, aluminum-magnesium-based alloys, lithium-magnesium-based alloys, lithium-aluminum-based alloys It is possible to adopt the form.

The solidification start temperature or solidification temperature of the metal constituting the heat storage member is a temperature region in which latent heat is likely to be expressed, and is adapted to the heat retention temperature region of the object, the heat retention temperature region of the exhaust system parts, and the activation region of the catalyst. Can be made. That is, the metal constituting the heat storage member can be selected such that the temperature range in which latent heat can be exerted is suitable for heat retention of the object, heat retention of exhaust system components, and heat retention of the catalyst. If the heat storage member is formed of an alloy in which a plurality of metals coexist, the solidification start temperature of the metal forming the heat storage member can be adjusted, so that the alloy composition can be selected to be suitable for heat retention.

When applied to an exhaust gas purifying catalytic converter as an exhaust system component, the converter has an inclined wall whose flow passage area increases in the gas flow passage from the gas inlet toward the catalyst storage chamber. Therefore, it is possible to adopt a mode in which the vacuum heat insulating chamber is disposed on at least a part of the inclined wall. In this case, since the vacuum heat insulating chamber is inclined, it is possible to secure the volume of the vacuum space of the vacuum heat insulating chamber while suppressing the axial length of the converter, and it is possible to enhance the heat insulating property and heat retaining property of the vacuum heat insulating chamber. . As the above-mentioned inclined wall, it is possible to adopt a shape in which it expands in a conical shape or a pyramidal shape, or a pseudo-conical shape or a pseudo-pyramidal shape from the gas inlet toward the catalyst storage chamber.

Further, the exhaust gas purifying catalytic converter has an inclined wall whose flow passage area increases from the gas inlet toward the catalyst storage chamber in the gas passage, and the heat storage member is at least a part of the inclined wall. Can be adopted. Since the heat storage member is also inclined, the charging amount of the heat storage member can be secured while suppressing the axial length of the converter, and the heat storage amount of the heat storage member can be increased.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment embodying the present invention will now be described with reference to FIG.
It will be specifically described with reference to. This embodiment is applied to an exhaust gas purifying catalytic converter, which is a typical example of an exhaust system component. The exhaust gas purifying catalytic converter 1 (holding portion) according to the present embodiment is for purifying exhaust gas discharged from an internal combustion engine mounted on a vehicle, and is provided with a gas inlet 10 through which the exhaust gas flows. , A gas outlet 12 through which exhaust gas flows, and a gas inlet 10 and a gas outlet 12
The gas flow path 13 connecting the gas flow paths 13 and the catalyst storage chamber 14 arranged in the middle of the gas flow path 13 are provided. The catalyst accommodating chamber 14 is formed by an extending cylindrical portion 16 extending in a straight cylindrical shape along the axial direction. A catalyst 2 (object) for purifying exhaust gas is stored in the catalyst storage chamber 14. The catalyst 2 is formed by supporting a catalyst substance (at least one of platinum, rhodium, and palladium) on a honeycomb carrier having an inlet end face 20 and an outlet end face 21. The honeycomb carrier may be a metal carrier or a ceramic carrier as long as it has a gas passage extending from the upstream side to the downstream side. A heat insulating material 15 is interposed between the outer wall surface of the catalyst 2 and the extended cylindrical portion 16 so as to surround the outer wall surface of the catalyst 2. The diameter of the gas inlet 10 is D
1, the inlet end face 20 of the catalyst 2 has a diameter D2, and the gas outlet 12 has a diameter D3, the diameter D of the gas inlet 10 is D.
1. The diameter D3 of the gas outlet 12 is the inlet end surface 20 of the catalyst 2.
Is set to be smaller than the caliber D2 (D1 <D2,
D3 <D2). Mounting flanges 18 having mounting holes 17 for mounting the converter 1 in the exhaust system are provided on the upstream and downstream sides of the converter 1, respectively.

The converter 1 is formed of a heat-resistant metal typified by stainless steel or the like. The converter 1 has, in the gas flow path 13 on the upstream side of the catalyst 2, an upstream inclined wall 3 whose flow path area increases from the gas inlet 10 toward the catalyst housing chamber 14. The inclined wall 3 on the upstream side expands in a conical shape or a pseudo-conical shape from the gas inlet 10 toward the catalyst housing chamber 14, and is formed so as to make one round around the center line P of the catalyst 2. . The sloped wall 3 on the upstream side has an inner sloped wall 30 and an outer sloped wall 3 so as to form a conical or pseudo-conical closed chamber 33.
It is formed of 1. The inner sloped wall 30 has a gas inlet 10
The shape is such that the diameter increases from the center to the catalyst storage chamber 14, and is formed so as to make one round around the center line P. The outer inclined wall 31 is coaxially arranged on the outer side of the inner inclined wall 30, has a shape whose diameter increases from the gas inlet 10 toward the catalyst housing chamber 14, and makes one turn around the center line P. Is formed in. Closed chamber 33
Is formed of an outer inclined wall 31 and an inner inclined wall 30.

The outer inclined wall 31 includes a charging window 34 opening to the upper part of the closed chamber 33, and a closing wall 35 closing the charging window 34.
Have and. The metal-based heat storage member 4 (object) is sealed in the sealed chamber 33. Since the heat storage member 4 is sealed in the closed chamber 33, leakage and deterioration of the heat storage member 4 are suppressed. In the manufacturing process, the liquid or solid heat storage member 4 is charged into the closed chamber 33 through the charging window 34 in the air atmosphere, the reduced pressure atmosphere or the vacuum atmosphere, and the closing wall 35 is joined by joining means such as welding. The charging window 34 is closed. Here, an inert gas (for example, argon gas or nitrogen gas) may be introduced into the space of the closed chamber 33 before closing the closed chamber 33 in which the heat storage member 4 is charged with the closing wall 35. In this case, deterioration of the heat storage member 4 can be suppressed.

As described above, the heat storage member 4 is enclosed in the closed chamber 33 inside the inclined wall 3. Therefore, the heat storage member 4 is also inclined so as to expand as it goes from the gas inlet 10 to the catalyst storage chamber 14, and thus the amount of the heat storage member 4 charged can be increased while suppressing the axial length dimension of the converter 1. it can. In addition, when the space volume of the closed chamber 33 is 100%, the heat storage member 4 is generally inserted so as to occupy a volume of 60 to 99% or 80 to 98% of 100% at room temperature. ing.

The metal forming the heat storage member 4 accumulates latent heat when the temperature rises to change from the solid state to the liquid state. Further, the metal forming the heat storage member 4 releases latent heat when the temperature is lowered and the liquid state is changed to the solid state. The temperature at which the metal forming the heat storage member 4 can develop latent heat is set in the activation temperature region of the catalyst 2 or in the temperature region near the activation temperature region. The metal forming the heat storage member 4 is specifically formed of a tin-zinc alloy. This alloy contains 50-90% tin and 50-10% zinc by weight. However, the metal forming the heat storage member 4 is not limited to the above alloy and the above composition. Since the solidification start temperature can be adjusted by forming the heat storage member 4 with an alloy in which a plurality of metal elements coexist in this way, the alloy composition can be selected to be suitable for keeping the temperature of the catalyst 2.

In the converter 1, in the gas passage 13 on the downstream side of the catalyst 2, the second inclined wall 5 on the downstream side whose flow passage area increases from the gas outlet 12 toward the catalyst accommodating chamber 14.
Have. The second inclined wall 5 on the downstream side widens from the gas outlet 12 toward the catalyst housing chamber 14. The exposed surface 5x of the second inclined wall 5 on the downstream side is exposed to the outside air in order to enhance heat dissipation, and thus can function as a heat dissipation promotion unit located between the gas outlet 12 and the catalyst 2. In this case, heat dissipation between the outlet end face 21 of the catalyst 2 and the gas outlet 12 can be promoted, and overheating of the catalyst 2 is suppressed. According to this embodiment, as shown in FIG.
The second inclined wall 5 on the downstream side is not provided with a heat storage member in order to enhance heat dissipation, and is not provided with a vacuum heat insulation chamber described later.

According to this embodiment, the converter 1 has a vacuum heat insulating chamber 6 in a vacuum state or a reduced pressure state on the upstream side of the catalyst 2 and a vaporizable metal 62 as a vaporizable substance enclosed in the vacuum heat insulating chamber 6. Have and. If the volume of the vacuum insulation chamber 6 is 100%, the vaporizable metal 62 occupies about 10 to 40% (volume ratio) of 100% at room temperature. However, the ratio of the vaporizable metal 62 is not limited to this. As can be understood from the description below, the vacuum heat insulation chamber 6
Exhibits heat insulation and heat retention when the use environment temperature is low, and enhances heat retention to the gas flow path 13 and the catalyst 2. However, when the use environment temperature rises, heat insulation and heat retention gradually decrease, and The heat and heat dissipation are gradually exhibited.

Since the vacuum heat insulating chamber 6 is provided on the outer peripheral side of the heat storage member 4, the heat of the heat storage member 4 can be suppressed from being released to the outside air when the heat insulating property and the heat retaining property are exhibited. The vacuum heat insulating chamber 6 is formed by the outer wall 61 and the outer inclined wall 31 by coaxially fixing the outer wall 61 to the outer peripheral side of the outer inclined wall 31 of the upstream inclined wall 3. Therefore, on the upstream side of the converter 1, the outer inclined wall 3
1, the inner inclined wall 30 and the outer wall 61 have a triple-wall structure, and in this sense as well, the heat insulation and heat retention at the upstream side of the catalyst 2 are enhanced when the use environment temperature is low.

Since the outer wall 61 is provided so as to go around the center line P of the catalyst 2 once, the vacuum heat insulating chamber 6 also has one center line P.
It is formed so as to go around. The vacuum heat insulating chamber 6 is arranged on the upstream side of the catalyst 2 in the gas flow path 13, that is, between the gas inlet 10 and the catalyst accommodating chamber 14. As the vaporizable metal 62 described above, zinc, a zinc alloy (for example, a zinc-tin alloy), selenium, or a selenium alloy is used. The boiling point of the vaporizable metal 62 is 550 to 1150 ° C. at atmospheric pressure, and particularly 670 to 11
Within the range of 50 ° C. The vaporizable metal 62 can be vaporized even in a temperature range below its boiling point.

As shown in FIG. 1, in the upper part of the vacuum insulation chamber 6,
An injection part 64 having an inlet 64x is provided. At the time of manufacturing, the liquid or solid vaporizable metal 62 is injected into the vacuum heat insulating chamber 6 from the injection port 64x of the injection unit 64, and then the injection unit 64 is held in a state where the vacuum heat insulating chamber 6 is maintained in a vacuum state or a reduced pressure state. The injection port 6 of the injection part 64 is closed by closing the injection part 64 with a joining means such as crushing or welding.
4x is closed and the vaporizable metal 62 is enclosed in the vacuum insulation chamber 6.

When the internal combustion engine is driven, high-temperature exhaust gas flows from the exhaust port of the internal combustion engine into the gas inlet 10 of the converter 1 in the direction of arrow X and further into the catalyst 2. Environmentally harmful substances such as nitrogen oxides contained in the exhaust gas are purified by the catalyst substance of the catalyst 2. The purified exhaust gas is discharged from the gas outlet 12. Since the exhaust gas discharged from the internal combustion engine has a high temperature, the catalyst 2 is heated. When the temperature of the catalyst 2 is in the activation temperature range of the catalyst 2, the exhaust gas purifying ability of the catalyst 2 is sufficiently exerted.

As described above, when the internal combustion engine is driven, the high-temperature exhaust gas flows through the gas flow path 13 and the catalyst 2. Therefore, the heat of the exhaust gas heats the heat storage member 4 and accumulates it in the heat storage member 4 as latent heat. . That is, the heat storage member 4 in the closed chamber 33
Accumulates latent heat by changing from a solid state to a liquid state. Further, since the heat of the exhaust gas is also transferred to the vacuum heat insulating chamber 6, the temperature of the vacuum heat insulating chamber 6 becomes high, and the vaporization of the vaporizable metal 62 in the solid state in the vacuum heat insulating chamber 6 progresses to liquefy and further vaporize. 62 changes its phase to accumulate latent heat. At this time, the frequency with which the vaporized particles of the vaporizable metal 62 fly in the vacuum heat insulating chamber 6 and collide with the outer wall 61 and the outer inclined wall 31 forming the closed chamber 33 increases dramatically,
The heat insulating property and heat retaining property of the vacuum heat insulating chamber 6 are lowered, and the heat transfer property and the heat radiating property of the vacuum heat insulating chamber 6 are increased. Therefore, the heat storage member 4
In the temperature region where the catalyst 2 and the catalyst 2 are overheated, the heat of the heat storage member 4 and the catalyst 2 can be released to the outside through the vacuum heat insulating chamber 6 having improved heat transfer and heat dissipation.
Also, overheating of the catalyst 2 is suppressed.

When the high temperature exhaust gas flows in the gas flow path 13 and the catalyst 2 in the direction of arrow X when the internal combustion engine is driven, the catalyst 2 functions as a resistor against the flow of the exhaust gas, and the flow velocity of the exhaust gas is Since the temperature decreases upstream of the inlet end surface 20 of the catalyst 2, the degree of involvement of exhaust gas in the heat storage member 4 provided upstream of the inlet end surface 20 of the catalyst 2 increases, and the heat storage member 4
The heat storage property of can be improved. Inclined wall 3 further upstream
Is widened and inclined so that the flow passage area increases toward the catalyst 2, and therefore the flow velocity of the exhaust gas also decreases in the upstream side of the inlet end surface 20 of the catalyst 2 in this sense, and the exhaust gas collects heat. The degree of involvement in the heat storage member 4 is increased, and the heat storage property of the heat storage member 4 can be improved.

According to this embodiment, the vacuum heat insulating chamber 6 is arranged adjacent to the heat storage member 4. In particular, the vacuum heat insulating chamber 6 is arranged adjacent to the outer peripheral side of the heat storage member 4. In this way, when the vacuum heat insulating chamber 6 is provided adjacent to the heat storage member 4, when the temperature of the heat storage member 4 becomes a high temperature region and becomes overheated when the internal combustion engine is driven, a vacuum having improved heat transfer and heat dissipation properties. Excessive heat of the heat storage member 4 can be released to the outside through the heat insulation chamber 6, so that overheating of the heat storage member 4 can be suppressed and the durability of the heat storage member 4 can be improved. .

By the way, when the internal combustion engine that has been driven stops, the high temperature exhaust gas does not flow to the catalyst 2, so that the temperature of the catalyst 2 gradually decreases. Similarly, the temperature of the heat storage member 4 is also lowered. However, as the temperature of the heat storage member 4 is lowered, the heat storage member 4 is changed from the liquid state to the solid state, so the heat storage member 4 releases the heat accumulated as latent heat to the outside together with the temperature reduction. As a result, the heat storage member 4
The air and exhaust gas in the upstream space MA between the catalyst and the inlet end surface 20 of the catalyst 2 are warmed.

When the internal combustion engine is stopped, the vacuum insulation chamber 6
Since the temperature is also lowered, the vaporizable metal 62 that has been vaporized in the vacuum heat insulating chamber 6 is lowered in temperature to be in a liquid state or a solid state. As a result, the vaporizable metal 62 releases the heat accumulated as latent heat to the outside, so that the high temperature state of the heat storage member 4 can be maintained for as long as possible, and as a result, the heat storage member 4 and the inlet end surface of the catalyst 2 can be maintained. Two
The air and exhaust gas in the upstream space MA between 0 and 0 can be warmed for a long time.

Further, as described above, the vaporizable metal 62 that has been vaporized in the vacuum heat insulating chamber 6 becomes liquid,
When it becomes a solid state, the degree of vacuum or the degree of reduced pressure of the vacuum heat insulating chamber 6 becomes high, and the heat insulating property and heat retaining property of the vacuum heat insulating chamber 6 are improved, so that the heat dissipation of the heat storage member 4 to the outside air is further suppressed. Therefore, the high temperature state of the heat storage member 4 can be maintained for a long time. Also in this sense, the air and exhaust gas in the upstream space MA between the heat storage member 4 and the inlet end surface 20 of the catalyst 2 can be warmed for a long time.

As described above, according to this embodiment, since the vacuum heat insulating chamber 6 is provided, when the temperature of the catalyst 2 and the heat storage member 4 becomes a high temperature region and becomes overheated when the internal combustion engine is driven. Since the excess heat of the catalyst 2 and the heat storage member 4 can be released to the outside through the vacuum heat insulating chamber 6 having improved heat transfer and heat dissipation due to the vaporization of the vaporizable metal 62, the catalyst 2 and the heat storage member 4 can be discharged. It is possible to suppress the overheating, and it is possible to improve the durability and extend the life of the catalyst 2 (target object) and the heat storage member 4 (target object).

When the internal combustion engine is stopped, the high temperature exhaust gas does not flow to the catalyst 2, so that the temperature of the catalyst 2 and the heat storage member 4 is lowered, but since the temperature of the vacuum heat insulating chamber 6 is also lowered, it is vaporized in the vacuum heat insulating chamber 6. The vaporizable metal 62 is cooled to become a liquid state or a solid state. As a result, when the vaporizable metal 62 that has been vaporized in the vacuum heat insulating chamber 6 becomes a liquid state or a solid state, the degree of vacuum or the degree of pressure reduction of the vacuum heat insulating chamber 6 becomes high, and the heat insulation of the vacuum heat insulating chamber 6 becomes high. Since the heat resistance and the heat retention are improved, the heat dissipation of the heat storage member 4 and the catalyst 2 to the outside air can be further suppressed. Therefore, the heat storage member 4 can be maintained in a high temperature state for a long time, and
The catalyst 2 can be maintained in its activation temperature range for a long time. Also in this sense, the air and exhaust gas in the upstream space MA between the heat storage member 4 and the inlet end surface 20 of the catalyst 2 can be warmed for a long time. Further, as the temperature of the vacuum heat insulating chamber 6 is lowered, the vaporizable metal 62 releases the heat accumulated as latent heat to the outside, so that the heat storage member 4
The high temperature state can be maintained for as long as possible, and thus the air and exhaust gas in the upstream space MA between the heat storage member 4 and the inlet end surface 20 of the catalyst 2 can be warmed for a long time.

Further, according to this embodiment, the vacuum heat insulating chamber 6 and the inclined wall 3 are arranged so as to be inclined so as to open widen from the gas inlet 10 toward the catalyst accommodating chamber 14.
The space volume of the vacuum heat insulating chamber 6 can be increased while suppressing the axial length dimension of the converter 1, and thus the heat insulating property, the heat radiating property, and the heat retaining property of the vacuum heat insulating chamber 6 can be increased. It is possible to maintain good heat insulation and heat retention over a long period of time. Therefore, after the internal combustion engine is stopped, the heat storage member 4 can positively warm the air or exhaust gas in the upstream space MA between the gas inlet 10 and the inlet end surface 20 of the catalyst 2. Therefore, when the internal combustion engine is restarted, the catalyst 2 can be returned to the activation temperature region thereof in a short time, and the exhaust gas purification performance at the time of restart can be improved. Further, according to this embodiment, when the internal combustion engine is stopped, the catalyst 2 is cooled and the temperature is lowered, and the heat storage member 4 is also lowered. However, since the heat storage member 4 provided between the gas inlet 10 and the catalyst housing chamber 14 releases the heat accumulated as latent heat to the outside when the internal combustion engine is stopped, the activation temperature of the catalyst 2 is as high as possible. Can be maintained in the area.

Further, when the internal combustion engine is stopped, the heat storage member 4 can positively warm the air and exhaust gas in the upstream space MA between the heat storage member 4 and the inlet end surface 20 of the catalyst 2. Therefore, when the internal combustion engine is restarted, the air and exhaust gas warmed in the upstream space MA between the heat storage member 4 and the inlet end surface 20 of the catalyst 2 are discharged by the exhaust gas discharged from the internal combustion engine by the catalyst 2 Will be immediately supplied to. Therefore, even when the temperature of the catalyst 2 drops below the activation temperature range thereof due to the stop of the internal combustion engine, the temperature of the catalyst 2 can be raised in a short time. Therefore, when the internal combustion engine is restarted, the catalyst 2 can be returned to the activation temperature region in a short time, and the exhaust gas purification performance at the time of restart can be improved.

Further, according to the present embodiment, the heat storage member 4, together with the vacuum heat insulating chamber 6 and the inclined wall 3, is arranged so as to incline so as to widen as it goes from the gas inlet 10 to the catalyst accommodating chamber 14, and therefore the converter. It is possible to increase the charging amount of the heat storage member 4 while suppressing the axial length dimension of No. 1, thereby increasing the heat storage amount of the heat storage member 4 at the time of temperature rise, and at the same time, to store the heat of the heat storage member 4 at the time of temperature decrease. It is possible to increase the heat radiation amount based on.

When the engine such as the internal combustion engine is restarted, in order to return the catalyst 2 to the activation temperature region in a short time,
Upstream space M between the heat storage member 4 and the inlet end surface 20 of the catalyst 2
It is preferable that the volume of A is large. In this respect, according to the present embodiment, the heat storage member 4 is arranged so as to be inclined so as to expand from the gas inlet 10 to the catalyst housing chamber 14, and therefore, between the heat storage member 4 and the inlet end surface 20 of the catalyst 2. The volume of the upstream space MA can be secured. As a result, the upstream space MA
It is possible to increase the total volume for heating the air and exhaust gas existing in the. Therefore, when the engine such as the internal combustion engine is restarted, it is possible to further contribute to returning the catalyst 2 to the activation temperature region in a short time.

(Second Embodiment) FIG. 2 shows a second embodiment of the present invention.
Shown in. The present embodiment has basically the same configuration as the above-mentioned first embodiment, and basically has the same operational effect.
Hereinafter, description will be made focusing on the parts different from the first embodiment. The vacuum heat insulating chamber 6 is also extended to the outer peripheral side of the extended cylindrical portion 16 and surrounds the outer peripheral surface 2m of the catalyst 2 (object). Therefore, when the vacuum heat insulation chamber 6 exhibits heat insulation and heat retention, the heat retention of the catalyst 2 is further ensured. On the other hand, when the vacuum heat insulating chamber 6 exhibits heat transfer properties and heat dissipation properties, overheating of the catalyst 2 is further suppressed. According to this embodiment, FIG.
As shown in, the vacuum heat insulating chamber 6 has a storage chamber 6w for storing the vaporizable metal 62 at the bottom thereof. Therefore, catalyst 2
The outer peripheral surface 2m and the heat storage member 4 (object) are surrounded by the vacuum space 6x of the vacuum heat insulation chamber 6, and the heat insulation and heat retention of the catalyst 2 and the heat storage member 4 are enhanced.

(Third Embodiment) A third embodiment of the present invention is shown in FIG.
Shown in. The present embodiment has basically the same configuration as the above-mentioned first embodiment, and basically has the same operational effect.
Hereinafter, description will be made focusing on the parts different from the first embodiment. In the converter 1 for exhaust gas purification, in the gas flow path 13 on the downstream side of the catalyst 2 (object), the flow path area increases from the gas outlet 12 toward the catalyst housing chamber 14, and the downstream second inclined wall 5B. Have. The second inclined wall 5 </ b> B on the downstream side expands from the gas outlet 12 toward the catalyst housing chamber 14, and is formed so as to go around the center line P of the catalyst 2 once. The second inclined wall 5B on the downstream side is formed of a second inner inclined wall 50B and a second outer inclined wall 51B so as to form a conical closed chamber 53B. The second inner sloping wall 50B extends from the gas outlet 12 to the catalyst storage chamber 1
The shape is such that the diameter increases toward 4 and is formed so as to go around the center line P once. The second outer sloping wall 51B is coaxially arranged outside the second inner sloping wall 50B, and has a shape in which the diameter increases from the gas outlet 12 toward the catalyst housing chamber 14, and around the center line P. It is formed so as to make one turn. Second closed chamber 53
B is formed by the second outer inclined wall 51B and the second inner inclined wall 50B.

The second heat storage member 4B (object) is hermetically sealed in the second sealed chamber 53B. Therefore, since the second heat storage member 4B is also tilted together with the second inclined wall 5B, it is possible to secure the charging amount of the second heat storage member 4B while suppressing the axial length dimension of the converter 1. According to this embodiment, the solidification start temperature of the downstream second heat storage member 4B may be the same as or different from the solidification start temperature of the upstream heat storage member 4 (object). When the temperature of the exhaust gas on the downstream side of the catalyst 2 is higher than the temperature of the exhaust gas on the upstream side of the catalyst 2,
The solidification start temperature of the downstream second heat storage member 4B can be made higher than the solidification start temperature of the upstream heat storage member 4.
Thereby, the heat storage property of the second heat storage member 4B on the downstream side can be ensured.

The converter 1 includes the second inclined wall 5B on the downstream side.
Also on the outer peripheral side of the second vacuum heat insulating chamber 6B which is in a vacuum state or a reduced pressure state to enhance the heat insulating property to the gas flow path 13, and a metal-based second vaporizable metal sealed in the second vacuum heat insulating chamber 6B. 62B. Second vacuum insulation chamber 6B
Is formed by the second outer wall 61B and the second outer inclined wall 51B by coaxially fixing the second outer wall 61B to the outer peripheral side of the second outer inclined wall 51B of the downstream second inclined wall 5B. There is. Therefore, even in the downstream side of the converter 1, the second
Outer inclined wall 51B, second inner inclined wall 50B, second outer wall 6
It has a triple wall structure of 1B, and in this sense also, the catalyst 2
The heat insulation and heat retention are improved in the downstream. As the above-mentioned second vaporizable metal 62B, zinc or a zinc alloy (for example, a zinc-tin alloy), or selenium or a selenium alloy is adopted. Second vaporizable metal 6
The boiling point of 2B is 550 to 1150 ° C. at atmospheric pressure, especially 67.
It is in the range of 0 to 1150 ° C. The boiling point of the second vaporizable metal 62B may be the same as that of the vaporizable metal 62, or may be high or low.

According to this embodiment, as shown in FIG. 3, the vacuum heat insulating chamber 6 is provided on the upstream side of the catalyst 2, and
Since the second vacuum heat insulating chamber 6B is also provided on the downstream side of the catalyst 2, when the temperature of the catalyst 2 rises, the vacuum heat insulating chambers 6, 6 are
Since B becomes a high temperature, vaporization of the vaporizable metal 6, 62B in the vacuum heat insulating chamber 6, 6B is progressing, and the vacuum heat insulating chamber 6, 6B
The heat transfer property and heat dissipation property of B are improved, and excess heat of the catalyst 2 can be released through the vacuum heat insulating chambers 6 and 6B.
The overheating of can be suppressed. On the other hand, when the temperature of the catalyst 2 drops as the internal combustion engine stops, the vaporizable metal 6
Since the temperature of 2, 62B is also lowered, liquefaction or solidification of the vaporizable metal 62, 62B that has been vaporized in the vacuum heat insulating chamber 6, 6B progresses, and the degree of vacuum or the degree of vacuum of the vacuum heat insulating chamber 6, 6B becomes high. Since the heat insulating properties and heat retaining properties of the heat insulating chambers 6 and 6B are improved, the temperature decrease of the catalyst 2 is suppressed. When the temperature of the catalyst 2 is further lowered, the vaporizable metal 62.62B which has been vaporized in the vacuum heat insulating chambers 6 and 6B is liquefied or solidified and the latent heat is released to the outside, so that the temperature of the catalyst 2 is further suppressed. It Therefore, the catalyst 2 is kept in the activation temperature region for as long as possible.

According to the present embodiment, as shown in FIG. 3, in addition to the heat storage member 4 being provided on the upstream side of the catalyst 2, the second heat storage member 4B is also provided on the downstream side of the catalyst 2. Therefore, when the internal combustion engine is driven, the heat of the high-temperature exhaust gas is accumulated as latent heat not only in the heat storage member 4 but also in the second heat storage member 4B. Therefore, when the internal combustion engine is stopped, the heat storage member 4 and the second heat storage member 4B release the heat accumulated as latent heat to the outside as the temperature drops, so that the upstream space MA between the heat storage member 4 and the catalyst 2 is released. And the exhaust gas is warmed and the downstream space M between the catalyst 2 and the second heat storage member 4B.
The air and exhaust gas in B are warmed. As a result, the heat retaining property for the catalyst 2 is improved when the internal combustion engine is stopped, and the catalyst 2 can be maintained in the activation temperature region for a long time. Further, even if the catalyst 2 falls below the activation temperature range due to the stop of the internal combustion engine, when the internal combustion engine is restarted, the catalyst 2 can be returned to the activation temperature range in a short time. It is possible to improve the exhaust gas purification performance immediately after the engine is restarted.

Further, according to the present embodiment, not only the heat storage member 4 but also the second heat storage member 4B is arranged so as to be inclined. Therefore, while suppressing the axial length dimension of the converter 1, the heat storage amount by the heat storage member 4, The amount of heat stored by the heat storage member 4B can be increased. Therefore, even if the internal combustion engine is stopped, the catalyst 2 can be maintained in the activation temperature region for a long time.
Further, when the internal combustion engine is restarted, the catalyst 2 can be returned to the activation temperature region in a short time, and the exhaust gas purification performance can be improved.

(Fourth Embodiment) A fourth embodiment of the present invention is shown in FIG.
Shown in. The present embodiment has basically the same configuration as the above-mentioned first embodiment, and basically has the same operational effect.
Hereinafter, description will be made focusing on the parts different from the first embodiment. The vacuum heat insulation chamber 6 so as to surround the outer peripheral surface 2 m of the catalyst 2.
C is provided coaxially in a ring shape. The vacuum insulation chamber 6C is formed by the outer wall 61C. Vacuum insulation room 6
A vaporizable metal 62C is enclosed in C. As the vaporizable metal 62C, zinc or a zinc alloy (for example, zinc-
Tin alloy), or selenium or a selenium alloy. The boiling point of the vaporizable metal 62C is 5 at atmospheric pressure.
It is in the range of 50 to 1150 ° C, especially 670 to 1150 ° C.

When the internal combustion engine is driven, the heat of the exhaust gas is also transferred to the vacuum heat insulating chamber 6, so that the temperature of the vacuum heat insulating chamber 6 becomes high and the vaporizable metal 62C in the vacuum heat insulating chamber 6C vaporizes. Therefore, the frequency with which the vaporized particles of the vaporizable metal 62C collide with the wall forming the closed chamber 33 dramatically increases, the heat insulating property and heat retaining property of the vacuum heat insulating chamber 6C decrease, and the heat transfer property of the vacuum heat insulating chamber 6C decreases. And the heat dissipation is gradually improved. Therefore, the vacuum insulation chamber 6 with improved heat transfer and heat dissipation
The heat of the catalyst 2 can be released to the outside via C,
Overheating of the catalyst 2 is suppressed, and the durability of the catalyst 2 can be improved.

(Fifth Embodiment) FIG. 5 shows a fifth embodiment of the present invention.
Shown in. The present embodiment has basically the same configuration as the above-mentioned first embodiment, and basically has the same operational effect.
Hereinafter, description will be made focusing on the parts different from the first embodiment. According to this embodiment, the heat storage member is not provided,
The vacuum heat insulating chamber 6 extends not only upstream of the catalyst 2 but also on the outer peripheral side of the extended cylindrical portion 16 and surrounds the outer peripheral surface 2 m of the catalyst 2. Therefore, when the vacuum heat insulation chamber 6 exhibits heat insulation and heat retention, the heat retention of the catalyst 2 is ensured. Further, when the vacuum heat insulating chamber 6 exhibits heat transfer and heat dissipation, the catalyst 2
Overheating is suppressed. According to the present embodiment, as shown in FIG. 5, the vacuum heat insulating chamber 6 has a storage chamber 6w for storing the vaporizable metal 62 at the bottom thereof. Therefore, the circumference of the outer peripheral surface 2m of the catalyst 2 is surrounded by the vacuum space 6x of the vacuum heat insulating chamber 6, and the heat insulating property and heat retaining property for the catalyst 2 are enhanced.

(Sixth Embodiment) A sixth embodiment of the present invention is shown in FIG.
Shown in. The heat pump device includes a container 8 as a holding unit that houses the hydrogen storage alloy 80 as an object, a vacuum heat insulating chamber 6D that covers the outer surface of the container 8, and a boiling point under atmospheric pressure sealed in the vacuum heat insulating chamber 6D. And a vaporizable metal 62D of 650 to 1150 ° C. As the vaporizable metal 62D,
Zinc or a zinc alloy (for example, a zinc-tin alloy), or selenium or a selenium alloy is used. The vaporizable metal 62 can be vaporized even in a temperature range below its boiling point.

When hydrogen is stored in the hydrogen storage alloy 80, heat is generated, so that the temperature of the hydrogen storage alloy 80 rises. At this time, since the temperature of the vacuum heat insulating chamber 6D becomes high together with the container 8, vaporization of the vaporizable metal 62D in the vacuum heat insulating chamber 6 is progressing, the heat transfer property and heat radiating property of the vacuum heat insulating chamber 6D are improved, and the hydrogen storage alloy. Excessive heat of 80 can be released to the outside through the vacuum heat insulating chamber 6D, overheating of the hydrogen storage alloy 80 can be suppressed, and deterioration of the hydrogen storage alloy 80 due to overheating can be suppressed.

On the other hand, the hydrogen storage alloy 80 in the container 8
When hydrogen is released from the hydrogen absorbing alloy 80, heat absorption occurs, so that the temperature of the hydrogen storage alloy 80 is lowered. At this time, since the temperature of the vaporizable metal 62D is also lowered, liquefaction or solidification of the vaporizable substance that has been vaporized in the vacuum heat insulating chamber 6D progresses, and the degree of vacuum or the degree of reduced pressure in the vacuum heat insulating chamber 6D increases. In this case, since the heat insulating property and the heat retaining property of the vacuum heat insulating chamber 6D are improved, the excessive temperature decrease of the hydrogen storage alloy 80 is suppressed. Further, when the temperature of the hydrogen storage alloy 80 is lowered, the vaporizable metal 62D that has been vaporized in the vacuum heat insulation chamber 6D is liquefied or solidified and the latent heat is released to the outside, so that the excessive temperature reduction of the hydrogen storage alloy 80 is further suppressed. To be done.

(Seventh Embodiment) A seventh embodiment of the present invention is shown in FIG.
Shown in. The heat treatment apparatus includes a container 8E as a holding unit that accommodates the metal material 88 as an object, a vacuum heat insulating chamber 6E that covers the outer surface of the container 8E, and a boiling point of 650 at atmospheric pressure sealed in the vacuum heat insulating chamber 6E. ~ 1150 ° C vaporizable metal 62
With E and. As the metal material 88, a casting such as flake graphite cast iron or spheroidal graphite cast iron, a titanium alloy, an aluminum alloy, or the like can be used. As the vaporizable metal 62E, zinc, a zinc alloy (for example, a zinc-tin alloy), selenium, or a selenium alloy is used. When the vaporizable metal 62E is heated, it can be vaporized even in a temperature range equal to or lower than its boiling point.

Since the container 8E is covered with the vacuum heat insulating chamber 6E having a high degree of vacuum, the heat retaining property of the metal material 88 is ensured if the metal material 88 is in an appropriate temperature range. However, when the temperature of the metal material 88 in the container 8E is excessive, the temperature of the vacuum heat insulating chamber 6E becomes high together with the container 8, so that the vaporizable metal 62 in the vacuum heat insulating chamber 6E is vaporized, and the vacuum heat insulating chamber The heat conductivity and heat dissipation of 6E are improved, the excess heat of the metal material 88 can be released to the outside through the vacuum heat insulating chamber 6E, and the overheat of the metal material 88 can be suppressed.

(Others) In the first embodiment described above, the honeycomb type catalyst 2 is applied. However, the present invention is not limited to this, and can be applied to a pellet type catalyst and other type catalysts. Although the metal forming the heat storage member 4 is specifically formed of a tin-zinc based alloy, it is not limited to this and may be a magnesium based or a tin based. Besides, the present invention is not limited to the embodiments described above and shown in the drawings, and can be implemented with appropriate modifications without departing from the scope of the invention.

From the above description, the following technical idea can be understood. (Additional Item 1) In any one of claims 4 to 6, the vaporizable substance has a boiling point of 550 to 550 at atmospheric pressure.
An exhaust system component having a temperature of 1150 ° C. (Appendix 2) In any one of claims 4 to 7, the vaporizable substance is at least one selected from zinc, a zinc alloy, cadmium, a cadmium alloy, selenium, a selenium alloy, magnesium, and a magnesium alloy. Exhaust system parts characterized by being formed of seeds.

[0062]

According to the heat retaining and radiating device of the first invention,
When the temperature of the object is lower than the predetermined temperature range, the vaporization of the vaporizable substance in the vacuum insulation chamber has not progressed so much, so that the degree of vacuum or the degree of reduced pressure in the vacuum insulation chamber is maintained high,
The heat insulation of the vacuum insulation chamber is high, and the heat insulation of the object can be maintained high. On the other hand, when the temperature of the target object rises, the temperature of the vacuum insulation chamber becomes high, so vaporization of the vaporizable substance in the vacuum insulation chamber is progressing, and the heat transfer and heat dissipation of the vacuum insulation chamber are improved. Excessive heat of the object can be released to the outside through the vacuum heat insulation chamber, and overheating of the object can be suppressed. Further, when the temperature of the object is lowered, the temperature of the vaporizable substance is also lowered, so that the vaporizable substance that has been vaporized in the vacuum heat insulating chamber progresses to be liquefied or solidified, and the degree of vacuum or the degree of reduced pressure in the vacuum heat insulating chamber is increased. In this case, the heat insulating property and heat retaining property of the vacuum heat insulating chamber are improved, so that the temperature reduction of the object is suppressed.

According to the exhaust system component of the second aspect of the present invention, when the temperature of the exhaust system component is lower than the predetermined temperature range, the vaporization of the vaporizable substance in the vacuum insulation chamber does not proceed so much, so that A high degree of vacuum or reduced pressure is maintained,
The heat insulation of the vacuum heat insulation chamber is high, and the heat insulation of exhaust system parts can be maintained high. On the other hand, when the temperature of the exhaust system components rises, the temperature of the vacuum heat insulating chamber becomes high, so vaporization of the vaporizable substance in the vacuum heat insulating chamber is progressing, and the heat transfer and heat dissipation of the vacuum heat insulating chamber are improved. Excessive heat of the exhaust system parts can be released through the vacuum insulation chamber, and overheating of the exhaust system parts can be suppressed. Further, when the temperature of the exhaust system parts is lowered, the temperature of the vaporizable substance is also lowered, so that liquefaction or solidification of the vaporizable substance that has been vaporized in the vacuum insulation chamber proceeds,
The degree of vacuum or the degree of reduced pressure in the vacuum insulation chamber increases. In this case, since the heat insulation and heat retention of the vacuum heat insulation chamber are improved, the temperature reduction of the exhaust system components is suppressed.

In the case of being applied to an exhaust gas purifying catalytic converter as an exhaust system component, when the temperature of the catalyst is lower than a predetermined temperature range, vaporization of the vaporizable substance in the vacuum heat insulation chamber has not progressed so much. The degree of vacuum or the degree of reduced pressure of the vacuum heat insulating chamber is maintained high, the heat insulating property of the vacuum heat insulating chamber is high, and the heat insulating property of the catalyst and the gas passage can be maintained high. On the other hand, when the temperature of the catalyst rises, the temperature of the vacuum heat insulating chamber becomes high, so vaporization of the vaporizable substance in the vacuum heat insulating chamber is progressing, and the heat transfer and heat dissipation of the vacuum heat insulating chamber are improved, and Excess heat can be released through the vacuum insulation chamber, and overheating of the catalyst can be suppressed. Further, when the temperature of the catalyst is lowered, the temperature of the vaporizable substance is also lowered. Therefore, liquefaction or solidification of the vaporizable substance that has been vaporized in the vacuum adiabatic chamber proceeds, and the degree of vacuum or the degree of reduced pressure in the vacuum adiabatic chamber increases. In this case, since the heat insulation and heat retention of the vacuum heat insulation chamber are improved, the temperature drop of the catalyst and the gas flow path is suppressed, and the catalyst is maintained in the activation temperature range as long as possible even after the engine such as the internal combustion engine is stopped. can do.

[Brief description of drawings]

FIG. 1 is a sectional view of an exhaust gas purifying catalytic converter according to a first embodiment.

FIG. 2 is a sectional view of an exhaust gas purifying catalytic converter according to a second embodiment.

FIG. 3 is a cross-sectional view of an exhaust gas purifying catalytic converter according to a third embodiment.

FIG. 4 is a sectional view of an exhaust gas purifying catalytic converter according to a fourth embodiment.

FIG. 5 is a sectional view of an exhaust gas purifying catalytic converter according to a fifth embodiment.

FIG. 6 is a cross-sectional view of the vicinity of a container containing a hydrogen storage alloy used in a heat pump device according to a sixth embodiment.

FIG. 7 is a sectional view of a heat treatment apparatus according to a seventh embodiment.

[Explanation of symbols]

In the figure, 1 is a converter (exhaust system part, holding part), 10 is a gas inlet, 12 is a gas outlet, 13 is a gas flow path, 2 is a catalyst (target), 3 is a slanted wall, 4 is a heat storage member (target). Thing), 4
B is a second heat storage member (object), 5 is a second inclined wall, 6 is a vacuum heat insulation chamber, 62 is a vaporizable metal (vaporizable substance), 8 is a container (holding part), 80 is a hydrogen storage alloy (target). Thing), 88
Indicates a metal material (object).

   ─────────────────────────────────────────────────── ─── Continued front page    F-term (reference) 3G091 AA02 AB01 BA04 CA08 FC07                       FC08 HA44                 3H036 AA04 AB33

Claims (6)

[Claims] 1. A holding section for holding an object whose temperature rises due to heating or heat generation, and a vacuum heat insulation chamber attached to the holding section and being in a vacuum state or a decompressed state to enhance heat insulation to the object. A heat insulation and heat dissipation device, comprising: a vaporizable substance that is enclosed in the vacuum heat insulation chamber and is vaporized with a temperature rise to reduce the heat insulation property of the vacuum heat insulation chamber and enhance the heat dissipation property. 2. The vaporizable substance according to claim 1,
A heat retaining and radiating device having a boiling point of 550 to 1150 ° C. under atmospheric pressure. 3. The vaporizable substance according to claim 1 or 2, wherein the vaporizable substance is formed of at least one selected from zinc, zinc alloy, cadmium, cadmium alloy, selenium, selenium alloy, magnesium and magnesium alloy. A heat insulation and heat dissipation device characterized in that 4. An exhaust system component having a gas inlet into which exhaust gas flows in, a gas outlet from which exhaust gas flows out, and a gas flow path connecting the gas inlet and the gas outlet, in a vacuum state or a reduced pressure state. A vacuum heat insulating chamber that enhances heat insulating properties for at least one of the gas inlet, the gas outlet, and the gas flow path; and a heat insulating property of the vacuum heat insulating chamber that is enclosed in the vacuum heat insulating chamber and is vaporized as the temperature rises. An exhaust system component having a vaporizable substance that lowers heat dissipation. 5. The exhaust system component according to claim 4, wherein the exhaust system component is an exhaust gas purifying catalytic converter having a catalyst accommodating chamber disposed in the gas flow passage for accommodating an exhaust gas purifying catalyst. Exhaust system parts. 6. The vacuum heat insulating chamber according to claim 4 or 5, wherein the vacuum heat insulating chamber is disposed on at least one of an upstream side of the catalyst, a downstream side of the catalyst, and an outer peripheral side of the catalyst. Exhaust system parts.