JP2584893Y2 - Deterioration determination device for exhaust gas purification device - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for judging the deterioration of an exhaust gas purifying apparatus provided with an unburned gas component adsorbing means for adsorbing unburned gas components in exhaust gas in an exhaust passage of an internal combustion engine.

[0002]

2. Description of the Related Art When an exhaust gas purification catalyst is inactive during a cold start of an internal combustion engine or the like, an unburned gas component in an exhaust passage is prevented to prevent the unburned gas component in the exhaust gas from being released to the atmosphere. An exhaust gas purifying apparatus provided with an unburned gas component adsorbing means for adsorbing methane is known from Japanese Utility Model Laid-Open No. 4-105925.

[0003]

The unburned gas component adsorbing means composed of granular activated carbon or zeolite has the property of adsorbing unburned gas components composed of hydrocarbons. When the adsorption capacity of the unburned gas component is reduced due to a change or the like, the unburned gas component may be released to the atmosphere without being adsorbed.

The present invention has been made in view of the above circumstances, and has as its object to prevent the release of unburned gas components to the atmosphere by accurately determining the degree of deterioration of the unburned gas component adsorption means.

[0005]

According to a first aspect of the present invention, there is provided an exhaust gas purifying apparatus, which is provided in an exhaust passage of an internal combustion engine. and unburnt gas components adsorbing means for adsorbing component, a temperature detecting means for detecting the temperature of the yet-combustible gas component adsorbing means provided in the unburnt gas components adsorbed unit, the fuel tank before
Connected to the exhaust passage upstream of the unburned gas component adsorption means
The unburned gas component supply passage and the unburned gas component supply passage
An on-off valve provided on the road and a predetermined time after the internal combustion engine is stopped
When the time has elapsed, the on-off valve is opened to open the fuel tank.
Supply the unburned gas component from the to the unburned gas component adsorption means,
Determining means for determining the degree of deterioration of the unburned gas component adsorption means according to the output of the temperature detection means at that time .

According to a second aspect of the present invention, there is provided an exhaust gas purifying apparatus for determining a deterioration of an exhaust gas purifying apparatus .
Bypass passage and exhaust gas provided in the bypass passage.
Unburned gas component adsorption means for adsorbing unburned gas components in gas
And the unburned gas provided in the unburned gas component adsorbing means.
Temperature detecting means for detecting the temperature of the component adsorbing means;
The ink upstream of the unburned gas component adsorbing means.
An unburned gas component supply passage connected to the
An on-off valve provided in the gas component supply passage;
A pair of switches provided at the junction and junction of the road
And a valve after the switching valve closes the bypass passage.
When the fixed time has elapsed, the on-off valve is opened to open the fuel
The unburned gas component from the tank is supplied to the unburned gas component adsorption means.
Supply according to the output of the temperature detecting means at that time.
Determination means for determining the degree of deterioration of the unburned gas component adsorption means
And characterized in that:

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

First, in FIG. 1 showing a first embodiment of the present invention, an intake passage 3 and an exhaust passage 4 are connected to an intake port 1 and an exhaust port 2 of an internal combustion engine E, respectively. The exhaust passage 4 indicates a flow path until exhaust gas discharged from the exhaust port 2 is released to the atmosphere. The exhaust passage 4 includes a hydrocarbon adsorbing catalyzer 5 as an unburned gas component adsorbing means, and an exhaust gas located downstream thereof. A purification catalyst 6 is provided.

An unburned gas component supply passage 8 connected to a fuel tank 7 as unburned gas component supply means is connected to the exhaust passage 4 of the internal combustion engine E at a position upstream of the hydrocarbon adsorbing catalyzer 5. Fuel gas component supply passage 8
Is controlled by a solenoid 11 driven by a solenoid driver 10.

The electronic control unit U includes an input circuit 31 to which signals from a temperature sensor 12 and an ignition switch 13 as temperature detecting means provided in the hydrocarbon adsorption catalyzer 5 are inputted, and the temperature sensor 12 and the ignition switch 13 A central processing unit 32 that performs arithmetic processing on the signal from the CPU based on a predetermined arithmetic program;
A ROM 33 for storing various calculation programs and various data used for calculation in the central processing unit 32; a RAM 34 for temporarily storing signals from the temperature sensor 12 and the ignition switch 13 and calculation results; An output circuit 35 that outputs a drive signal to the alarm lamp 14 that warns the driver 10 and the deterioration of the hydrocarbon adsorption catalyzer 5 is provided.

Next, the operation of the first embodiment having the above configuration will be described.

When the temperature of the exhaust gas purifying catalyst 6 has not reached the catalyst activation temperature as in the case of a cold start of the internal combustion engine E, the unburned gas component contained in the exhaust gas is adsorbed by the hydrocarbon adsorbing catalyzer 5 and Release to the atmosphere is suppressed. When the operation of the internal combustion engine E is continued, the temperature of the hydrocarbon adsorbing catalyzer 5 rises due to the heat of the exhaust gas, the unburned gas components adsorbed there are purged and burned, and the hydrocarbon adsorbing catalyzer 5 is unburned. The gas component is released. Further, the temperature of the exhaust gas purification catalyst 6 also rises to the catalyst activation temperature or higher, and a state in which harmful substances in the exhaust gas can be purified is established.

When a predetermined time elapses after the stop of the internal combustion engine E is detected by a signal from the ignition switch 13 and the temperature of the exhaust system is sufficiently lowered, the solenoid driver 10 is instructed by a command from the electronic control unit U. , The solenoid 11 is driven, the on-off valve 9 is opened, and the unburned gas component from the fuel tank 7 is supplied to the hydrocarbon adsorption catalyzer 5. The unburned gas component is adsorbed and liquefied by the hydrocarbon adsorbing catalyzer 5, and generates heat at that time to increase the temperature of the hydrocarbon adsorbing catalyzer 5.

As shown in FIG. 2, when the function of the hydrocarbon adsorbing catalyzer 5 is normal and the ability to adsorb unburned gas components is large, a sufficient amount of unburned gas components is adsorbed to absorb hydrocarbons. When the temperature of the adsorption catalyzer 5 rapidly rises and the unburned gas component is adsorbed to the limit amount, the temperature converges to a relatively high value. On the other hand, if the function of the hydrocarbon adsorbing catalyzer 5 is deteriorated due to aging or the like, and the ability to adsorb the unburned gas component is reduced, the amount of adsorption of the unburned gas component is reduced and the hydrocarbon adsorbing catalyzer 5 is reduced. The temperature does not rise too much and converges to a relatively low value. Therefore, a predetermined threshold value is stored in the ROM 33 of the electronic control unit U in advance, and when the final temperature of the hydrocarbon adsorbing catalyzer 5 having adsorbed the unburned gas component reaches the threshold value, it is determined to be normal. If the threshold value is not reached, it can be determined that the battery has deteriorated. It is also possible to determine the deterioration of the hydrocarbon adsorption catalyzer 5 based on the temperature change amount with respect to the unburned gas component introduction amount. Then, when the deterioration of the hydrocarbon adsorption catalyzer 5 is determined, the alarm lamp 14 operates to notify the user.

As described above, the deterioration of the hydrocarbon-adsorbing catalyzer 5 can be reliably determined, so that the deteriorated hydrocarbon-adsorbing catalyzer 5 is replaced to prevent the unburned gas components from being released into the atmosphere. Becomes possible.

FIG. 3 shows a second embodiment of the present invention.
In the second embodiment, the hydrocarbon adsorbing catalyzer 5 is provided and the unburned gas component supply passage 8 is connected to a bypass passage 15 that bypasses an intermediate portion of the exhaust passage 4. Switching valves 16 and 17 each composed of a butterfly valve are provided at a branch portion and a junction portion of the bypass passage 15, respectively. The switching valve 16 at the branch portion is switched by a solenoid 19 connected to a solenoid driver 18, and The switching valve 17 at the junction is switched by a solenoid 21 connected to a solenoid driver 20.

According to the second embodiment, when the temperature of the exhaust gas purifying catalyst 6 has not reached the catalyst activation temperature, as in the case of the cold start of the internal combustion engine E, the two switching valves 16 and 17 are turned on. The exhaust gas is switched to the solid line position and the exhaust gas is
And the unburned gas components contained in the exhaust gas are adsorbed by the hydrocarbon adsorbing catalyzer 5 to suppress emission to the atmosphere. When the temperature of the hydrocarbon adsorbing catalyzer 5 and the exhaust gas purifying catalyst 6 is sufficiently increased by continuing the operation of the internal combustion engine E, the unburned gas component adsorbed on the hydrocarbon adsorbing catalyzer 5 is burned, and the exhaust gas is exhausted. The temperature of the gas purification catalyst 6 rises above the catalyst activation temperature. In this manner, when the internal combustion engine E is completely warmed up, the two switching valves 1
6 and 17 are switched to the chain line positions, and the exhaust gas is supplied to the exhaust gas purification catalyst 6 without passing through the bypass passage 15 and purified.

After a predetermined time has passed since the bypass passage 5 was closed and the temperature of the hydrocarbon adsorbing catalyzer 5 was sufficiently lowered, the on-off valve 9 was opened to open the fuel tank 7.
Is supplied to the bypass passage 15 and adsorbed by the hydrocarbon adsorbing catalyzer 5. Then, by monitoring the temperature rise accompanying the adsorption of the unburned gas component by the temperature sensor 12, the deterioration of the hydrocarbon adsorption catalyzer 5 is determined in the same manner as in the first embodiment, and when the deterioration is determined, an alarm lamp is provided. The notification is performed by activating 14.

Thus, according to the second embodiment, the first
The same operation and effect as the embodiment can be obtained.

Although the embodiment of the present invention has been described in detail, the present invention is not limited to the above embodiment, and various design changes can be made.

[0021]

As described above, according to the invention] According to the invention as set forth in claim 1, the unburnt gas components adsorbed means provided in an exhaust passage of an internal combustion engine, unburned from the fuel tank into the unburnt gas components adsorbed means By monitoring the temperature change of the unburned gas component adsorption means by the temperature detection means while supplying the gas component, it is possible to determine whether the unburned gas component adsorption means is functioning normally or deteriorated. This makes it possible to replace the deteriorated unburned gas component adsorption means at an early stage and prevent the unburned gas component from being released into the atmosphere.

According to a second aspect of the present invention,
Unburned in the bypass that bypasses the exhaust passage of the internal combustion engine
Gas component adsorption means is provided, and this unburned gas component adsorption means
Temperature detection while supplying unburned gas components from the fuel tank
Monitoring temperature change of unburned gas component adsorption means by means
Whether the unburned gas component adsorption means is functioning normally
It can be determined whether or not it has deteriorated. This allows
Replace the deteriorated unburned gas component adsorption means at an early
Emission of sulfur components into the atmosphere can be prevented. Only
Also, by closing the bypass passage with a pair of switching valves,
Even during operation of the internal combustion engine, the unburned gas component adsorption means is inferior.
The determination of the degree of conversion can be performed.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of a deterioration determination device for an exhaust gas purification device according to a first embodiment.

FIG. 2 is a graph showing the relationship between the amount of adsorption of unburned gas components and temperature.

FIG. 3 is an overall configuration diagram of a deterioration determination device for an exhaust gas purification device according to a second embodiment.

[Explanation of symbols]

4 exhaust passage 5 hydrocarbon adsorbent catalyzer (unburnt gas components adsorbed means) 7 Fuel tank 8 unburnt gas component supply passage 9-off valve 12 Temperature sensor (temperature detecting means) 15 bypass passage 16 switching valve 17 switching valve E internal combustion engine U electronic control unit (judgment means)

──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Toshikazu Okeyani 1-4-1 Chuo, Wako-shi, Saitama Pref. Honda R & D Co., Ltd. (58) Field surveyed (Int.Cl. ⁶ , DB name) F01N 3 / 08-3/36

Claims (2)

(57) [Scope of request for utility model registration] An unburned gas component adsorbing means (5) provided in an exhaust passage (4) of an internal combustion engine (E) for adsorbing unburned gas components in exhaust gas; 5)
Temperature detecting means (12) for detecting the temperature of the unburned gas component adsorbing means (5), and a fuel tank (7).
An exhaust passage upstream of the unburned gas component adsorption means (5);
An unburned gas component supply passage (8) connected to (4);
On-off valve (9) provided in unburned gas component supply passage (8)
And when a predetermined time has elapsed after the internal combustion engine (E) is stopped
The on-off valve (9) is opened at first and the fuel tank (7) is opened.
These unburned gas components are supplied to the unburned gas component adsorption means (5).
And a determination means (U) for determining the degree of deterioration of the unburned gas component adsorption means (5) according to the output of the temperature detection means (12) at that time. Deterioration determination device for purification device. 2. An exhaust passage (4) of an internal combustion engine (E) is
A bypass passage (15) passing therethrough;
(15) is provided to adsorb unburned gas components in exhaust gas
Means for adsorbing unburned gas components (5)
The unburned gas component adsorbing means provided in the adsorbing means (5);
Temperature detecting means (12) for detecting the temperature of (5);
The tank (7) is set at a higher position than the unburned gas component adsorption means (5).
Unburned gas component connected to the upstream bypass passage (15)
The supply passage (8) and the unburned gas component supply passage (8)
An on-off valve (9) provided and the bypass passage (15)
A pair of switching valves respectively provided at the junction and the junction of
(16, 17) and before the switching valve (16, 17)
A predetermined time has passed after the bypass passage (15) was closed.
When the on-off valve (9) is opened and the fuel tank
Means for adsorbing the unburned gas component from (7)
(5) and the temperature detecting means (12) at that time.
Of the unburned gas component adsorption means (5) according to the output of
Determining means (U) for determining the degree
A deterioration determination device for an exhaust gas purification device.