Chemical apparatus and process disinfecting – deodorizing – preser – Chemical reactor – Waste gas purifier
Patent
1997-04-15
1999-05-11
Tran, Hien
Chemical apparatus and process disinfecting, deodorizing, preser
Chemical reactor
Waste gas purifier
422171, 422179, 422180, 422199, 422211, 422221, 422222, 60300, F01N3/10
Patent
active
059025573
DESCRIPTION:
BRIEF SUMMARY
TECHNICAL FIELD
The present invention relates to a device for purifying the exhaust gas of an internal combustion engine. More particularly, the present invention relates to an electrically heated catalyst device, the catalyst support of which is composed of a metallic honeycomb body, and the temperature of the catalyst support can be raised to a catalyst activating temperature in a short period of time when heat is generated by supplying electricity.
BACKGROUND ART
Exhaust gas discharged from an internal combustion engine incorporated into a vehicle contains harmful chemical substances such as HC (hydrocarbon), CO (carbon monoxide) and NO.sub.x (nitrogen oxides). Therefore, conventionally, a catalyst converter used as an exhaust gas purifying device is arranged in an exhaust gas passage of the internal combustion engine. However, it is known that a rate of purification of a three-way catalyst used for the catalyst converter to purify the harmful substances contained in exhaust gas is low when the catalyst temperature is low, that is, when the catalyst is in an inactive condition. Accordingly, the conventional catalyst converter is disadvantageous in that exhaust gas can not be sufficiently purified when the catalyst is in an inactive condition immediately after the internal combustion engine has been started.
In order to solve the above problems, there is proposed an exhaust gas purifying device having an electrically heated catalyst device in which the catalyst support is made of metal and this metallic catalyst support is heated to a catalyst activity temperature (300 to 400.degree. C.) in a short period of time by supplying electricity when the internal combustion engine is started or the catalyst is in an inactive condition due to a low temperature.
As shown in FIG. 29, the exhaust gas purifying device is composed as follows. There is provided an external metallic cylinder 1 connected to the exhaust gas passage of an internal combustion engine. In the external metallic cylinder 1, there are provided an electrically heated catalyst support 2, which is heated by supplying electricity, and a main catalyst support 3, wherein the electrically heated catalyst support 2 and the main catalyst support 3 are arranged in series at a predetermined interval. In the electrically heated catalyst support 2, there is provided a central electrode 6, and an electrode section 8A of this central electrode 6 is led to the outside of the external metallic cylinder 1. Between this electrode section 8A and an external electrode 8B attached to a portion of the external metallic cylinder 1, there is arranged a battery 9 and a switch SW. When this switch SW is turned on, an electric current is fed to the electrically heated catalyst support 2 to be heated, so that heat is generated in the catalyst support 2.
As shown in FIG. 30(a), the electrically heated catalyst support 2 is composed as follows. A sheet of metallic foil 4 formed into a corrugated form, which will be referred to as a corrugated foil 4 hereinafter in this specification, and a flat sheet of metallic foil 5, which will be referred to as a flat foil 5 hereinafter in this specification, are put on each other, and the respective longitudinal end portions of the corrugated foil 4 and the flat foil 5 are joined and wound around the central electrode 6 while they are put on each other, so that a spirally-shaped metallic foil laminated body, which is referred to as a honeycomb body, can be formed. In general, these corrugated foil 4 and flat foil 5 are made of alloy of iron containing aluminum, for example, the composition is 20% Cr-5% Al-75% Fe, and the thickness of the foil is approximately 50 .mu.m.
FIG. 30(b) is a view showing one end face of the honeycomb body 7 composed of the metallic corrugated foil 4 and the flat foil 5. In honeycomb body 7, the corrugated foil 4 and the flat foil 5 are put on each other and wound round the central electrode 6. As a result, around the central electrode 6, there are formed a large number of spiral passages P in the axial dire
REFERENCES:
patent: 5140812 (1992-08-01), Cornelison et al.
patent: 5232671 (1993-08-01), Brunson et al.
patent: 5240682 (1993-08-01), Cornelison et al.
patent: 5317869 (1994-06-01), Takeuchi
patent: 5323608 (1994-06-01), Honma
Kako Takuzou
Konya Shogo
Nakashima Yuuji
Ogai Masahiko
Sakurai Kazuhiro
Nippon Steel Corporation
Toyota Jidosha Kabushiki Kaisa
Tran Hien
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