JPH0424095Y2 - - Google Patents

Description

[Detailed description of the invention] (a) Technical field of the invention This invention collects and purifies particulate matter such as carbon particles (hereinafter referred to as particulate) contained in the exhaust gas of a diesel engine. The present invention relates to a reproducing device for a particulate trap filter.

(b) Background of the technology Generally, the exhaust gas of a diesel engine contains particulate, and if this particulate is released into the atmosphere as it is, it may cause problems such as air pollution. It is necessary to collect the particulates with a filter provided in the passage to purify the exhaust gas. If particulate continues to be collected, the filter will become clogged, and the pressure of the exhaust gas upstream of the filter will increase, which will create operating resistance for the diesel engine, resulting in a decrease in diesel engine output. This problem occurs. Therefore, from the viewpoint of preventing a decrease in the output of the diesel engine, the clogged particulate is burned and removed by a burner device, and the filter member is regenerated.

(c) Prior art and problems Conventionally, as a regenerating device for such a particulate trap filter, for example,
The one shown in Japanese Patent Application No. 2003-100003 or in FIG. 7 is known.

This conventional technique will be explained with reference to FIG.

As shown in the figure, a filter b for collecting particulate matter is provided in the exhaust gas passage a, and a burner device c is provided upstream of this filter b for burning and removing the particulate matter collected by the filter b.
is installed. The ignition (by glow plug d), combustion, and amount of heat supplied in this burner device c are as follows:
This is performed in response to a signal command from the control circuit e.
On the input side of this control circuit e, there is an exhaust pressure detector f that sends a signal for determining whether to regenerate the filter b;
An exhaust temperature detector g that sends a signal to determine whether burner device c is ignited, and a diesel engine rotation speed detector h and a diesel engine load detector i that send signals to determine the amount of heat to be supplied to burner device c.
are connected.

However, in conventional particulate trap filter regeneration equipment, the amount of heat supplied to the burner device (amount of light oil, amount of air) was determined based on the assumption that the outside air temperature was room temperature (20°C) and did not change. . Therefore, when the outside air temperature is high, the amount of heat supplied becomes excessive, causing the filter to melt and crack, leading to the filter being destroyed. Furthermore, when the outside air temperature is low, the amount of heat supplied becomes insufficient, resulting in a problem that the regeneration efficiency of the filter decreases.

(d) Purpose of the invention This invention was made to solve the above-mentioned problem.The purpose of this invention is to reduce the amount of heat supplied to the heating device when the outside temperature is high, prevent damage to the filter, and reduce the amount of heat supplied. It is an object of the present invention to provide a particulate trap filter regeneration device that saves energy, increases the amount of heat supplied to a heating device when the outside air temperature is low, and prevents a decrease in filter regeneration efficiency.

(e) Structure of the invention In order to achieve the above object, the present invention includes a filter that collects particulate matter in the middle of the exhaust pipe of a diesel engine, and a filter that is disposed upstream of this filter so that particulate matter is collected by the filter. In the particulate trap filter regeneration device, the particulate trap filter regenerating device is equipped with a particulate trap filter heating device that burns and removes particulates, which increases the amount of heat supplied to the filter when the outside air temperature is low regardless of the exhaust temperature, A control circuit is provided to reduce the amount of heat supplied to the filter when the temperature is high.

(f) Effect of the invention In the invention, the control circuit increases the amount of heat supplied to the filter when the outside temperature is low;
Control is performed to reduce the amount of heat supplied to the filter when the outside air temperature is high.

(g) Embodiments of the invention Examples of the invention will be described in detail below with reference to the drawings.

FIG. 1 is an overall configuration diagram of a particulate trap filter reproducing apparatus according to an embodiment of the present invention.

A particulate trap filter regeneration device according to an embodiment of the present invention includes a filter 2 installed in the middle of an exhaust pipe 1 to collect particulate matter.
A light oil burner 3 disposed upstream of the filter 2 burns and removes particulate matter collected by the filter 2, a glow plug 4 that ignites the light oil burner 3, and a detector and control circuit 5. A control device 6 outputs a signal command by a control circuit 5 based on the input signal from the change detector.

The control system of the present invention is shown in the block diagram of FIG.

On the input side of the control circuit 5, a diesel engine outside air temperature detector 7 provided outside the exhaust pipe 1;
A diesel engine rotation speed detector 8 attached to the diesel engine, a diesel engine load detector 9 that detects the load based on, for example, the opening degree of the accelerator pedal, and an exhaust gas temperature detector 10 in front of the filter 2; An exhaust pressure detector 11 on the front side of the filter 2 is connected.

A light oil burner 3 and a glow plug 4 are connected to the output side of the control circuit 5. The control circuit 5 controls the ON/OFF operation of the light oil burner 3 and adjusts the opening/closing degree. Moreover, it is also possible to use other heating devices such as an electric heater for the light oil burner 3.

The control details of the present invention will be explained with reference to FIGS. 3 to 5.

The outside air temperature signal detected by the diesel engine outside air temperature detector 7 is input to the control circuit 5,
As shown in FIG. 4, a control pattern i for the light oil burner 3 is determined in accordance with the outside temperature.

The control pattern i in FIG. 4 described above shows the relationship between the outside air temperature and the amount of heat supplied to the filter 2, and the pattern i on the vertical axis in FIG. 4 shows the amount of heat supplied to the filter 2. In Figure 4, as the outside air temperature approaches a low temperature (temperature close to T ₀ ), the amount of heat supplied increases, and the amount of heat close to pattern 0 is supplied, and the outside air temperature becomes high (temperature close to T _o ).
The closer it gets to n, the smaller the amount of heat supplied becomes.
An amount of heat close to that is supplied.

The rotational speed signal detected by the diesel engine rotational speed detector 8 and the load signal detected by the diesel engine load detector 9 are input to the control circuit 5, and as shown in FIG. Control patterns Ai and Fi for the light oil burner 3 are determined in accordance with the rotation speed and diesel engine load.

As shown in FIG. 3, the light oil burner 3
The amount of heat (amount of light oil, amount of air) to be supplied to is determined.
Based on the amount of heat supplied, the control circuit 5 outputs an opening/closing degree adjustment command to the light oil burner 3.

Next, the operation of the present invention will be explained with reference to FIGS. 4 to 6.

In FIG. 6, when the engine is started (step S1) and the vehicle is running, the exhaust pressure is detected by the exhaust pressure detector 11 (step S1).
S2). In step S3, it is determined whether the exhaust pressure is higher than a predetermined exhaust pressure _P0 . If the predetermined exhaust pressure P ₀ is not reached, a loop R1 is formed,
Regeneration of filter 2 is not performed. Predetermined exhaust pressure
When _P0 is reached, regeneration of filter 2 starts (step S4). The glow plug 4 turns ON (step S5), the temperature of the glow plug 4 increases,
The light oil burner 3 is turned on (step S6).
In step S7, ignition of the light oil burner 3 is determined based on a predetermined exhaust gas temperature _Tf0 .
That is, if the exhaust gas temperature T _f detected by the exhaust gas temperature detector 10 is lower than the predetermined temperature T _f0 , a loop R2 is formed. When the exhaust gas temperature T _f becomes equal to or higher than the predetermined temperature T _f0 , ignition of the light oil burner 3 is confirmed, and the glow plug 4 is turned off (step S8).

Next, as shown in FIG. 4, a control pattern i for the light oil burner 3 is determined based on the outside air temperature T.
That is, in FIG. 6, the outside air temperature T is a predetermined temperature.
When the amount of heat is less than _T0, control pattern 0, which provides the largest amount of heat to be supplied, is selected (step S9, step S10).
The outside air temperature T is higher than the predetermined temperature T ₀ and the predetermined temperature
When T is less than ₁ , control pattern 1 is selected (step S11, step S12). When the outside air temperature T is higher than the predetermined temperature _T1 and lower than the predetermined temperature _T2 , control pattern 2 is selected (step S13, step S14). When the outside air temperature T is higher than the predetermined temperature T _o-1 and less than the predetermined temperature T _o , control pattern n is selected (step S15, step S16). Outside temperature T
is higher than the predetermined temperature T _o, the control pattern (n
+1) is selected (step S17).

Then, as shown in FIG. 5, control patterns Ai and Fi for the light oil burner 3 are determined depending on the rotation speed and load of the diesel engine. That is, as shown in FIG. 6, in step S18, first, the diesel engine rotation speed r reaches a predetermined rotation speed.
It is determined whether r is higher than ₀ . If the diesel engine rotation speed is lower than the predetermined rotation speed r ₀ , control patterns A ₁ and F ₁ are selected (step S22).
When the diesel engine rotational speed r is equal to or higher than the predetermined rotational speed _r0 , the process proceeds to step S19, where it is determined whether the diesel engine load H is greater than the predetermined load _H0 . If the load is smaller than the predetermined load H ₀ , control patterns A ₂ and F ₂ are selected (step S21). When the load is greater than or equal to the predetermined load H ₀ , control patterns A ₁ and F ₁ are selected (step S20). This control pattern i, Ai,
Once Fi is selected, the program will proceed in the selected form even if the input signal changes.

As described above, when the control patterns i, Ai, and Fi are determined based on the outside air temperature T, the rotation speed r of the diesel engine, and the load H, the amount of heat to be supplied to the filter 2 is determined based on this (step
S23).

In particular, _the relationship between the outside air temperature and the amount of heat supplied is as described above. High temperature ( _To
The amount of heat supplied becomes smaller as the temperature approaches the pattern n (as shown in FIG. 4).

Then, the filter 2 is regenerated, and in step S24, it is determined whether the combustion time in the light oil burner 3 has exceeded a predetermined time _t0 from the start of regeneration. When the predetermined time t ₀ has not elapsed, a loop R3 is formed (arrow 2). When the predetermined time t ₀ has passed, the light oil burner 3
It becomes OFF state (step S25). Then, the regeneration of the filter ends, and the exhaust pressure decreases and returns to the original state (loop R4, arrow 1).

According to the particulate trap filter regeneration device having the above configuration, when the outside temperature T is high, the control circuit 5 lowers the amount of heat supplied to the filter 2 to an appropriate value, thereby destroying the filter 2. It is possible to prevent this and save the amount of heat supplied.
Furthermore, when the outside air temperature T is low, the control circuit 5 increases the amount of heat supplied to the filter 2 to prevent a decrease in filter regeneration efficiency.

(h) Effects of the invention As described above, according to the invention, when the outside temperature is high, the amount of heat supplied to the filter can be lowered to an appropriate value, preventing the filter from being destroyed and saving the amount of heat supplied. Moreover, when the outside air temperature is low, the amount of heat supplied to the filter is increased, and a decrease in filter regeneration efficiency can be prevented.

[Brief explanation of the drawing]

FIG. 1 is an overall configuration diagram of a particulate trap filter regeneration device according to an embodiment of the present invention;
Fig. 2 is a block diagram of the control system, Fig. 3 is a block diagram showing the procedure for determining the amount of heat supplied to the light oil burner, Fig. 4 is a control pattern diagram for outside air temperature, and Fig. 5 is a diagram of the diesel engine rotation speed and FIG. 6 is a flow chart of the present embodiment, and FIG. 7 is an overall configuration diagram of a conventional particulate trap filter regeneration device. 1... Exhaust pipe, 2... Filter, 3... Light oil burner, 4... Glow plug, 5... Control circuit, 6
... Control device, 7 ... Diesel engine outside temperature detector, 8 ... Diesel engine rotation speed detector, 9 ... Diesel engine load detector, 10
...Exhaust gas temperature detector, 11...Filter front exhaust pressure detector.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) A filter is installed in the exhaust pipe of a diesel engine to collect particulate matter, and a filter is installed upstream of this filter to burn and remove the particulate matter collected by the filter. In the particulate trap filter regeneration device, the amount of heat supplied to the filter is increased when the outside air temperature is low, and the amount of heat supplied to the filter is increased when the outside air temperature is high, regardless of the exhaust temperature. A regenerating device for a particulate trap filter, characterized in that a control circuit is provided to reduce the amount of heat supplied to the particulate trap filter. (2) The instruction to increase or decrease the amount of supplied heat is given in response to a signal from the diesel engine speed detected by the diesel engine speed detector and the diesel engine load detected by the diesel engine load detector. A particulate trap filter regeneration device according to claim 1, characterized in that the regeneration device is operated by a control circuit.