KR20190098462A - Adiabatic Catalytic Converter of Vehicle for Cold Start - Google Patents

Abstract

The present invention relates to an adiabatic catalytic converter of a vehicle for cold start time reduction, which comprises: a housing composed of an area of an expansion pipe and a reduction pipe and a cylindrical area surrounding a catalyst; and an insulating layer formed in an inlet variable exhaust valve and an outlet variable exhaust valve of exhaust gas. Moreover, a distance between an inner pipe and an outer pipe of the housing is constant in the cylindrical area surrounding the catalyst of the housing, and the distance between the inner pipe and the outer pipe is increased by being close to the catalyst in the area of the expansion pipe and the reduction pipe of the housing. In addition, the distance between the inner pipe and the outer pipe is increased by being close to the center of the inlet variable exhaust valve.

Description

Adiabatic Catalytic Converter of Vehicle for Cold Start

The present invention relates to an automobile adiabatic catalytic converter having a housing having a heat insulating layer and an inlet / outlet variable exhaust valve to maintain a catalyst temperature even when the vehicle is not driven, thereby reducing the time for cold start.

Catalysts are used in the exhaust system to reduce harmful substances such as carbon monoxide and unburned hydrocarbons in automobile exhaust gases. The catalyst must be heated to a sufficient temperature (operating temperature) in order to be activated. The catalyst used in the exhaust system is heated by the heat of the exhaust gas so that the pollutant removal is not performed properly in the cold start mode before it is sufficiently heated after starting. This results in 50-80% of the total hazardous substances in cold start mode. Therefore, it is necessary to allow the catalyst to reach operating temperature within a short time after cold start.

In order to heat the catalyst quickly, the catalytic part is placed close to the engine, and the method of heating with electricity is used. have. In addition, there is a method of additionally attaching a device for capturing unburned hydrocarbons generated in a cold start section, but practical trapping materials have not been developed.

That is, in order to rapidly increase the catalyst temperature during cold start, the catalytic converter needs to be insulated or insulated from the outside temperature so that the temperature of the finally used catalyst is maintained even after stopping the vehicle operation.

Korean Patent Publication No. 10-2013-0027650

The present invention has been made in order to solve the above problems, an object of the present invention is to provide an automobile catalytic converter capable of shortening the start-up time by including a heat insulating layer in the housing tube wall and the entrance and exit variable exhaust valve.

Automotive thermal insulation catalytic converter of the present invention for solving the above problems is formed in the housing and exhaust gas inlet variable exhaust valve and outlet variable exhaust valve consisting of the expansion tube and the reduction tube region and the cylindrical region surrounding the catalyst, the housing is formed during the housing In the cylindrical area surrounding the catalyst, the distance between the housing inner and outer pipes is constant, and the distance between the inner and outer pipes increases in the enlarged or reduced pipe area of the housing, and the distance between the inner and outer pipes increases, and toward the center of the inlet variable exhaust valve. The interval is increased.

The present invention made as described above to prevent the temperature decrease of the catalyst by blocking the temperature decrease by the outside air using the inlet and the outlet and the adiabatic variable exhaust valve as well as maintaining the temperature of the catalytic converter using a heat insulating layer in the automotive catalytic converter. It does not disturb the flow of exhaust gas and does not affect the performance of the vehicle. On the other hand, injecting a phase change material instead of the insulating layer can be maintained without deterioration of the catalyst activation temperature up to about 12 hours after starting the day after the vehicle stops running.

1 is an exhaust crab structure equipped with a conventional catalytic converter.
Figure 2 is a detailed structure of the catalytic converter ring apparatus is applied to the inlet and outlet variable exhaust valve according to the principle of the present invention.

In order to fully understand the present invention, preferred embodiments of the present invention will be described with reference to the accompanying drawings. Embodiment of the present invention may be modified in various forms, the scope of the invention should not be construed as limited to the embodiments described in detail below. This embodiment is provided to more completely explain the present invention to those skilled in the art. Therefore, the shape of the elements in the drawings and the like may be exaggerated to emphasize a more clear description. It should be noted that the same members in each drawing are sometimes shown with the same reference numerals. In addition, detailed descriptions of well-known functions and configurations that are determined to unnecessarily obscure the subject matter of the present invention are omitted.

1 is an example of a conventional catalytic converter, the exhaust gas is a structure that is discharged through the muffler after the harmful gas is removed through the catalytic reaction at the catalyst activation temperature in the catalytic converter. The housing of the catalytic converter has a cylindrical housing 20 (20) area holding the catalyst carrier and an enlarged pipe 10 area where the exhaust gas flow path is expanded at the connection from the exhaust pipe to the catalyst carrier, and then again after the catalyst carrier. In order to be connected to the exhaust pipe, the exhaust gas flow path is reduced to the reduction tube 30 area.

2 is provided with an inlet variable exhaust valve 40 at the inlet side of the exhaust pipe and an outlet variable exhaust valve 50 at the outlet side of the exhaust pipe, but the variable exhaust valve itself may be formed as a double wall having a heat insulation layer in the hollow part. . In addition, the housing of the catalytic converter can also be formed in a double tube or double wall structure of the inner tube and the outer tube.

As the exhaust gas passes through the expansion pipe 10, the exhaust gas flow rate decreases and the residence time increases, and as the exhaust gas flows through the reduction pipe 30, the exhaust gas flow rate increases again. According to the present invention, the cylindrical housing 20 holds the catalyst carrier in the housing, the enlarged tube 10 region in which the exhaust gas flow path is enlarged at the connection portion to the catalyst carrier, and the exhaust gas is connected to the exhaust pipe after passing through the catalyst carrier. The housing in each of the region of the reduction tube 30 in which the gas flow path is reduced may form a double tube having an inner tube and an outer tube, but may have different intervals between the inner tube and the outer tube.

First, the cylindrical housing 20 region may maintain a constant distance between the inner tube and the outer tube. The enlarged tube 10 region and the reduced tube 30 region are closer to the catalyst, the larger the distance between the inner tube and the outer tube. This is because the closer to the catalyst carrier, the thicker the insulation layer should be formed in order to maintain the catalyst activation temperature for a certain time after the start-up.

In addition, the amount of exhaust gas may be controlled by the exhaust gas inlet variable exhaust valve 40 and the outlet variable exhaust valve 50. The inlet and outlet variable exhaust valves may have a heat insulating layer formed of a hollow part formed of an inner wall and an outer wall. . In the case of the inlet and outlet variable exhaust valves, exhaust gas is mainly collected at the center, and the catalyst carrier also has a high temperature in the central region, so that the gap between the inner wall and the outer wall that forms the double wall of the inlet and outlet variable exhaust valves increases toward the center. Can be formed.

That is, the catalyst converter is insulated to stop the operation and maintain the catalyst temperature during the parking. In particular, by applying a variable exhaust valve having a heat insulation structure at the inlet and outlet of the catalytic converter, it is possible to prevent the temperature drop of the catalyst due to the outside air. For heat insulation, a vacuum layer may be applied as the heat insulation layer.

By adding a vacuum layer between the inner wall and the outer wall constituting the variable exhaust valve disk, it is possible to prevent the temperature of the catalyst caused by the outside air.

If the catalytic converter is formed in a vacuum layer, but the outside air is not blocked, the temperature of the catalyst is maintained at about LOT (Light-Off Temperature) until about 2 hours. However, in the case where the inlet and outlet portions are blocked with ceramic fiber insulation, temperatures of more than LOT can be maintained for up to 3 hours. The variable exhaust valve is applied to not only the inlet but also the outlet as in the present invention, and the variable exhaust valve is opened so that the exhaust gas supply is sufficient during the catalytic reaction, and it is variable in the non-run section or time that needs to maintain the LOT temperature of the catalyst carrier. By closing the exhaust valve, the LOT temperature maintainable time can be further extended. On the other hand, in the case of supplementing the thermal insulation performance by filling a phase change material, etc. in the thermal insulation layer, the temperature of the catalyst can be maintained above LOT more than 12 hours. Inlet and outlet variable exhaust valves can be actuated by actuators or pneumatics.

In general, if the home arrival time after work at 8:00 and the next day at 8:00 hours, the overnight driving time of the car is within 12 hours.In the structure that improves insulation and blocks outside air, the temperature of the catalyst during the non-operation time is LOT. We can keep more than this.

The present invention not only maintains the temperature of the catalytic converter by using a heat insulating layer, but also blocks the temperature decrease caused by outside air by using an inlet and an outlet and a heat insulating variable exhaust valve, thereby preventing the flow of exhaust gas and thus affecting the performance of the vehicle. It is possible to shorten the cold start time by preventing the temperature drop of the catalyst without giving a notice.

10: housing cylindrical tube
20: enlarged tube
30: reduction tube
40: inlet variable exhaust valve
50: outlet variable exhaust valve

Claims (8)

In the automotive catalytic converter,
A housing comprising a magnifying tube and a reducing tube region and a cylindrical region surrounding the catalyst;
Insulation catalyst conversion device for cold start time reduction for the cold start time, characterized in that the insulating layer is formed in the housing, the exhaust gas inlet variable exhaust valve and the outlet variable exhaust valve. The method of claim 1,
The thermal insulation layer of the housing is an automotive insulation catalytic converter for shortening the start-up time, characterized in that divided into the inner tube and the exterior to form a hollow. The method of claim 2,
In the cylindrical region surrounding the catalyst of the housing, the thermal insulation catalytic converter for reducing the time to start the cold start, characterized in that the interval between the housing inner tube and the exterior is constant. The method of claim 2,
In the enlarged tube or reduced tube region of the housing, the closer the catalyst is, the greater the distance between the inner tube and the exterior is characterized in that the automotive thermal catalytic converter for shortening the start-up time. The method of claim 1,
The thermal insulation layer of the inlet variable exhaust valve and the outlet variable exhaust valve is a vehicle insulation catalytic converter for shortening the cold start time, characterized in that to form a hollow by the inner tube and the appearance. The method of claim 5,
Automotive insulation catalytic converter for reducing the time to start the cold start, characterized in that the interval between the inner tube and the exterior increases toward the center of the inlet variable exhaust valve. The method of claim 6,
The outlet variable exhaust valve is a vehicle adiabatic catalytic converter for shortening the start-up time, characterized in that the interval between the inner tube and the exterior is constant. The method according to any one of claims 1 to 7,
The thermal insulation layer is a car thermal insulation catalytic converter for shortening the cold start time, characterized in that the phase change material is filled.

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