JPH0710018Y2 - Regeneration device for filter for collecting exhaust particulates of internal combustion engine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a device for a filter for collecting exhaust particulates of an internal combustion engine.

<Prior Art> As a conventional example of a regeneration device for an exhaust particulate collection filter,
There are the following (see Japanese Utility Model Laid-Open No. 64-3017).

That is, a filter for collecting exhaust particulates is provided in the exhaust passage of the diesel engine, and a burner is provided in the exhaust passage on the upstream side of the filter. When a predetermined amount of exhaust particulates are collected by the filter, the burner is burnt to heat and burn the exhaust particulates collected by the filter to regenerate the filter.

In addition, instead of the burner, there is one in which an electric heater and an exhaust throttle control device regenerate the filter.

<Problems to be Solved by the Invention> However, when the burner, the heater, and the exhaust throttle control device are used to regenerate the filter, there is a problem in that the operating energy of them becomes large and the fuel consumption deteriorates.

The present invention has been made in view of such circumstances, and an object thereof is to provide a regeneration device capable of regenerating a filter with a small amount of operating energy.

<Means for Solving the Problem> Therefore, the present invention is directed to a filter for collecting exhaust particulates or an exhaust passage upstream of the filter for accumulating exhaust heat and accumulating heat by a heat generating medium, and the heat generating medium. And a supply device that supplies the heat-generating medium from the heat-generating medium storage device to the accumulator when the filter is regenerated.

<Action> In this way, the exhaust heat is stored by the heat storage element during non-regeneration, while the heat generating medium is supplied to the heat storage element during regeneration to heat the heat storage element, thereby heating the filter to remove exhaust particulates. It was burned and the filter was regenerated.

<Embodiment> An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows an embodiment of the present invention.

In the figure, a filter 3 with a catalyst for collecting exhaust particulates in exhaust gas is installed in an exhaust passage 2 of a diesel engine 1, and a heat storage container 4 is installed in an exhaust passage 2 upstream of the filter 3. There is. Calcium oxide (CaO) as a heat storage element is stored in the heat storage element container 4, and _a plurality of exhaust passages 2A are formed so as to pass through the upstream and downstream sides.

A water storage tank 5 is provided as a heat generation medium storage device that stores water as a heat generation medium, and the water storage tank 5 is connected to the heat storage container 5 via a solenoid valve 6. The solenoid valve 6 is opened and closed by a control device 7 including a microcomputer described later. An opening 8 for releasing water vapor is formed on the outer wall of the heat storage container 4.

Exhaust pressure sensors 9 and 10 are provided upstream and downstream of the filter 3, respectively, and detection signals of the exhaust pressure sensors 9 and 10 are input to the control device 7. In addition, a detection signal from a temperature sensor 11 that detects the exhaust gas temperature at the inlet of the filter 3 is input to the control device 7.

Here, calcium oxide is changed to calcium hydroxide by heating the water is supplied _{(C a (OH) 2)} , decomposes into calcium hydroxide and calcium oxide absorbs receives heat and water characteristics have.

Here, the solenoid valve 6 and the control device 7 constitute a supply device.

Next, the operation will be described.

The control device 7 determines the regeneration timing of the filter 3 based on the pressure difference between the exhaust pressure sensors 9 and 10 and the temperature detected by the temperature sensor 11. Then, when it is determined to be the regeneration time, the control device 7 opens the electromagnetic valve 6 to supply water from the water storage tank 5 to the heat storage container 4.

As a result, the calcium oxide in the heat storage container 4 chemically reacts with water to generate heat at a relatively high temperature (eg 500 to 600 ° C.) and a relatively short time (eg 5 to 20 minutes). Due to this heat generation, the exhaust gas temperature rises, the exhaust particulates collected by the filter 3 are burned, and the filter 3 is regenerated.

After the regeneration is completed, the solenoid valve 6 is closed and the water supply is stopped. The calcium hydroxide produced in the heat storage container 4 has a relatively low temperature (for example, 200 ° C).
It absorbs exhaust heat of up to 300 ° C., decomposes into calcium oxide for a relatively long time (for example, 4 hours), and stores heat.

As described above, when the filter 3 is regenerated, water is supplied to the calcium oxide to generate heat so as to regenerate the filter 3, while the exhaust heat is used to decompose calcium hydroxide into calcium oxide to store heat when the filter 3 is not regenerated. Therefore, the filter can be regenerated with less energy as compared with the conventional example, and the fuel consumption and the like can be improved.

In this embodiment, the water vapor is released into the atmosphere through the opening 8. However, the water vapor may be condensed in the condenser and returned to the water storage tank 5 for reuse.

2 and 3 show a second embodiment of the present invention. In the following embodiments, the same elements as those in the first embodiment are not included in the first embodiment.
The same reference numerals as in the figure are given and the description thereof is omitted.

In this embodiment, a plurality of filters 22 are arranged in parallel and attached to the heat storage container 21.

Even with this configuration, the same effect as that of the first embodiment can be obtained.

FIG. 4 shows a third embodiment of the present invention.

In this embodiment, a bypass passage 31 that bypasses the filter 3 and the heat storage container 4 is formed, and the first opening / closing valve 32 is provided in the bypass passage 31, while the first passage is provided at the inlet of the heat storage container 4. The two on-off valves 33 are interposed.

Then, at the regeneration timing of the filter 3, the control device 34 opens the first opening / closing valve 32 and drives the second opening / closing valve 33 to close to a predetermined opening degree.

As a result, most of the exhaust gas flows downstream of the filter 3 via the bypass passage 31, and part of the exhaust gas is introduced into the heat storage container 4, so that the rate of increase in the exhaust gas temperature can be increased more than in the first embodiment. In addition, the storage heat generating container 4 can be downsized.

A hydrogen storage alloy or the like is used as the heat storage element, and in this case, hydrogen is used as the heat generating medium.

<Effects of the Invention> As described above, the present invention stores the exhaust heat in the heat storage element when the filter is not regenerated and supplies the heat generating medium to the heat generation element to regenerate the filter when the filter is regenerated. Since this is done, the filter can be regenerated with less energy than before, and fuel consumption can be improved.

[Brief description of drawings]

1 is a block diagram showing an embodiment of the present invention, FIG. 2 is a block diagram showing a second embodiment of the present invention, and FIG. 3 is a sectional view of the same.
FIG. 4 is a block diagram showing a third embodiment of the present invention. 2 ... Exhaust passage, 3 ... Filter, 4 ... Heat storage container, 5 ...
Water tank, 6 ... Solenoid valve, 7 ... Control device

Claims (1)

[Scope of utility model registration request] 1. An internal combustion engine equipped with a filter for trapping exhaust particulate matter, which is interposed in an exhaust passage of an engine, and which stores heat of exhaust gas provided in the filter or in an exhaust passage upstream of the filter and which generates heat by a heat generating medium. An internal combustion engine comprising: a body, a heat generating medium storage device that stores the heat generating medium, and a supply device that supplies the heat generating medium from the heat generating medium storage device to the storage heat generating body when the filter is regenerated. Regeneration device for engine exhaust particulate collection filter.