JPH0550566B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a diesel engine equipped with a diesel particulate collection member, and more particularly to a protection device for the diesel particulate collection member.

Diesel engine exhaust contains particulate, a combustible, fine carbonized compound, which is the main cause of black smoke in the exhaust. For example, the exhaust temperature of this particulate is
If the temperature exceeds 500℃, it will spontaneously ignite and burn when the vehicle is running at high speed and under high load (hereinafter referred to as "self-combustion").
However, during steady driving or idling (which accounts for more than 90% of vehicle operation) where the temperature does not reach 500℃,
It is released directly into the atmosphere.

However, since particulate matter may be harmful to the human body, research has been actively conducted in recent years to install a diesel particulate collection member in the exhaust passage of a vehicle diesel engine.

By the way, as this diesel particulate collection member is used, it tends to collect and accumulate particulate matter and block the exhaust passage. Research is also active.

Such regeneration devices include, for example, the use of various burners, the retardation of injection pumps, and the discharge of exhaust gas containing a large amount of carbon monoxide compounds, which are activated by oxidation catalysts to make them highly combustible. It has been proposed to use a device that does this.

However, with such conventional means, especially when using a particulate collection member (diesel particulate oxidizer; DPO) with a catalyst containing platinum, palladium, or rhodium, deceleration cannot be achieved when the DPO temperature is sufficiently high. If this is done, the excess air ratio will increase and the combustion of the particulate will become more active, while the exhaust flow rate will decrease and the amount of heat removed will become smaller, so the exhaust temperature will decrease during the regeneration of the diesel particulate collecting member If the temperature increases too much, there is a problem that in the worst case, the diesel particulate collection member may melt or the catalyst equipped with the diesel particulate collection member may deteriorate.

The present invention aims to solve these problems by injecting a predetermined amount of fuel when the temperature of the diesel particulate collection member is above a predetermined value and the diesel engine is in a deceleration state. It is an object of the present invention to provide a diesel particulate collection member protection device that prevents an excessive air ratio from becoming excessive and suppresses a temperature rise during regeneration of the diesel particulate collection member. .

Therefore, the diesel particulate collection member protection device of the present invention is a diesel particulate collection member disposed in the exhaust passage of the diesel engine to collect particulate particulate from the combustion chamber of the diesel engine. , a regeneration mechanism capable of regenerating the diesel particulate collecting member by burning particulate collected in the diesel particulate collecting member;
A first detection device comprising a regeneration control means for controlling the operation of the regeneration mechanism and a fuel injection amount control means for controlling the amount of fuel injected into the diesel engine, and for detecting the temperature of the diesel particulate collection member. and a second detection means for detecting the operating state of the diesel engine, the temperature of the diesel particulate collection member being set to a predetermined value in response to signals from the first and second detection means. In addition, particulate combustion suppressing means is provided for outputting a control signal to the fuel injection amount control means for increasing the combustion injection amount to the diesel engine when the diesel engine is in a deceleration state. It is a feature.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings. The figures show a diesel particulate collection member protection device as an embodiment of the present invention, and FIG. 1 is an overall configuration diagram thereof, and FIG. Its block diagram, Fig. 3, is a diagram showing the arrangement of the injection pump lever opener, Figs. FIG. 9 is a hydraulic system diagram for the fuel injection timing control means.

As shown in FIGS. 1 and 2, this diesel engine E has a main chamber formed by a cylinder block 1, a cylinder head 2, a piston (not shown), and a main chamber formed in the cylinder head 2 (not shown). It has an auxiliary room that does not

Also, in the main compartment of this diesel engine E,
An intake passage 3 is connected via an intake valve (not shown), and an exhaust passage 4 is connected via an exhaust valve (not shown), and this exhaust passage 4 contains diesel particulate matter that captures particulate matter in the exhaust gas. A collection member 5 is interposed.

Note that particulates here refer to flammable fine particles mainly composed of carbon and hydrocarbons, with an average diameter of about 0.3 μm, and which self-ignite at temperatures of 500°C or higher (350°C or higher in the presence of an oxidation catalyst). .

The diesel particulate collection member 5 is a deep trap type heat-resistant ceramic foam with a catalyst containing platinum, palladium, or rhodium inside (this is a flat plate whose cross-sectional shape is oval, oblong, or rectangular). etc.)
Hereinafter, this diesel sepakulate collection member will be described as described above.
It is abbreviated as DPO (diesel particulate oxidizer).

The DPO 5 communicates with the atmosphere via a muffler 6 and receives exhaust gas from the engine E via a turbine of a turbocharger 7 and a heat insulating pipe 8.

A pressure sensor 10 that detects the exhaust pressure in the exhaust passage 4 on the inflow and outflow side of the DPO 5 and outputs a detection signal to the ECU 9 (described later) controls the electromagnetic three-way switching valves (hereinafter referred to as "electromagnetic valves" as necessary) 11 and 12. Attached via.

Each solenoid valve 11, 12 receives a control signal from an electronic control unit (ECU) 9 constituted by a computer or the like through its respective solenoid 11a, 12a, and performs suction control on its valve body 11b, 12b. , when the valve body 11b is in the protruding state, atmospheric pressure P ₀ is applied via the air filter 13 (this P ₀ is
When the valve body 11b is in the suction state and the valve body 12b is in the protruding state, the downstream (outlet) exhaust pressure _P2 of the DPO 5 is the downstream pressure P2, and when the valve bodies 11b and 12b are in the suction state, the upstream (inlet) of the DPO is It is designed to detect exhaust pressure _P1 .

Furthermore, a temperature sensor (thermocouple) 14 is provided in the exhaust passage 4 close to the inlet (upstream) of the DPO 5 to detect the DPO inlet exhaust temperature Tin.
Exhaust passage 4 close to the outlet (downstream) of DPO5
A temperature sensor (thermocouple) 16 is provided to detect the DPO outlet exhaust gas temperature To.

Further, a temperature sensor (thermocouple) 15 is provided to detect the temperature Tf inside the DPO 5. That is, these temperature sensors 14 to 16 constitute a first detection means for detecting the DPO temperature.

Detection signals from each of these temperature sensors 14 to 16 are input to the ECU 9.

By the way, the fuel injection pump 17 attached to this diesel engine E can adjust the fuel injection timing by a fuel injection timing control means 18 which constitutes a regeneration mechanism upon receiving a control signal from the ECU 9. An injection pump lever opening sensor 19 constituting a second detection means is attached to the injection pump 17, and pump lever opening information is sent to the ECU 9.
It is now output to .

Note that the reference numeral 20 indicates a rotation speed sensor that detects the rotation speed of the engine 1.

In the intake passage 3 formed by the intake manifold fixed to the engine E and the intake pipe following this,
In order from the upstream side (atmosphere side): the air cleaner, the compressor of the turbocharger 7, and the intake throttle valve 21.
is installed.

The intake throttle valve 21 is driven to open and close by a diaphragm pressure response device 22.
This pressure response device 22 includes a diaphragm 22 connected to a rod 22a that drives an intake throttle valve 21.
b, but an air filter 23 is provided in the pressure chamber 22c partitioned by the diaphragm 22b.
An atmospheric passage 24 that guides atmospheric pressure Vat through the vacuum passage 24 and a vacuum passage 26 that guides the vacuum pressure Vvac from a vacuum pump 25 are connected to each other. An electromagnetic on-off valve (hereinafter referred to as an "electromagnetic valve") 28 is interposed.

And the solenoid 27 of each electromagnetic valve 27, 28
When a control signal by duty control is supplied from the ECU 9 to a, 28a, each valve body 27b, 28
b is controlled by suction, whereby the pressure (negative pressure) supplied to the pressure chamber 22c of the pressure response device 22 is adjusted, the rod 22a is retracted as appropriate, and the intake throttle valve 21 is throttled. Amount controlled.

Further, one end of a passage 29 for exhaust gas recirculation (hereinafter referred to as EGR) is open in the intake passage 3 on the downstream side of the intake throttle valve 21.

The other end of the EGR passage 29 opens to a portion of the exhaust passage 4 on the upstream side of the portion of the turbocharger 7 where the turbine is disposed.

In addition, at the intake passage side opening of the EGR passage 29,
Exhaust gas recirculation amount control valve (hereinafter referred to as "EGR valve")
30 is provided, and this EGR valve 30 is driven to open and close by a diaphragm type pressure response device 31. This pressure response device 31
is equipped with a diaphragm 31b connected to a rod 31a that drives the EGR valve 30, and a pressure chamber 31c partitioned by this diaphragm 31b is supplied with atmospheric pressure through an air filter 32.
Atmospheric passage 33 that guides Vat and vacuum pump 2
The vacuum passage 34 which guides the vacuum pressure Vvac from 5 is connected, and these passages 33,
34 are respectively provided with an electromagnetic on-off valve (hereinafter referred to as "electromagnetic valve" as needed) 35 and an electromagnetic on-off valve (hereinafter referred to as "electromagnetic valve" as necessary) 36.

And the solenoid 35 of each electromagnetic valve 35, 36
When a control signal by duty control is supplied from the ECU 9 to a, 36a, each valve body 35b, 36
b is controlled by suction, whereby the pressure (negative pressure) supplied to the pressure chamber 31c of the pressure response device 31 is adjusted, the rod 31a is retracted as appropriate, and the opening degree of the EGR valve 30 is adjusted. is controlled.

Note that the opening degree of the intake throttle valve 21 is the same as that of the intake throttle valve 21.
A pressure sensor 38 is attached to the intake passage 3 on the downstream side of the installation position of 1 via an electromagnetic three-way switching valve (hereinafter referred to as "electromagnetic valve" as necessary) 37.
The opening degree of the EGR valve 30 is detected by the feedback signal sent to the ECU 9 from the pressure response device 3.
This is detected by a feedback signal sent to the ECU 9 from a position sensor 39 that detects the movement of the first rod 31a.

Then, the solenoid 37a of the electromagnetic valve 37
When a control signal is supplied from the ECU 9, each valve body 3
7b is designed to be suction-controlled, whereby the intake pressure downstream of the intake throttle valve 21 is supplied to the pressure sensor 38 via the passage 40, and when the valve body 37b of the electromagnetic valve 37 protrudes, the air filter 41 atmospheric pressure is supplied to the pressure sensor 38.

A position sensor 45 is also provided to detect the movement of the rod 22a of the pressure response device 22.
The opening degree of 1 is fed back to ECU9.

Furthermore, a regeneration mechanism (or regeneration auxiliary mechanism) capable of promoting the regeneration of DPO5 by supplying high-temperature gas for particulate combustion containing oxygen gas from the diesel engine E to DPO5 is provided to burn the particulate collected in DPO5 and promote the regeneration of DPO5. The fuel injection timing control means 18 is constituted by a fuel injection timing adjustment device that retards the timing of fuel injection from the injection pump 17.

When the injection pump 17 is configured as a distribution type injection pump, the fuel injection timing control means 1
8, a hydraulic automatic timer (internal timer) is used in which a timer piston is driven by hydraulic pressure from a hydraulic pump to move the relative position of the cam plate and roller.

Further, as shown in FIG. 9, the fuel injection timing control means 18 includes a solenoid timer solenoid valve 18b and a retard valve 18c for changing the state of the oil pressure p applied to the timer piston 18a, and regenerates the DPO5. When attempting to promote this, the solenoid timer solenoid valve 18b is turned on to close the oil passage 50, and the retard valve 18c is turned off to open the oil passage 51, thereby supplying pressure oil p to the timer piston 18a.
By not supplying the engine speed, a retarded characteristic (low advance characteristic or full retard characteristic) is realized regardless of the engine speed, as shown by the symbol L in FIG.

In addition, in other cases, the retard valve 18
By turning on and off the solenoid valve 18b for the solenoid timer with the oil passage 51 turned on, that is, with the oil passage 51 closed, the characteristics shown with the symbol H (hyde bounce characteristic) and the symbol M in FIG. The following characteristics (middle advanced characteristics) can be obtained.

Here, in FIG. 9, numerals 52 to 54 are orifices, 55 is a check valve, 56 is a regulating valve, 57 is a feed pump, 58 is a pump chamber, 59 is a plunger, 60 is a delivery valve, and 61 is a nozzle. There is.

Note that the oil pressure p acting on the timer piston 18a
A conventionally known timer control valve may be used as a means for changing the state of the timer control valve.

Further, the fuel injection amount is increased by the driver operating the accelerator pedal to correct the decrease in output due to the delay in the injection timing.

Furthermore, the injection pump 17 is provided with an injection pump lever 17a, as shown in FIG.
3 in the counterclockwise direction in FIG. 3 to increase the fuel injection amount, and conversely, when the accelerator pedal is released, it rotates in the clockwise direction by the action of a return spring (not shown). The amount of fuel injected is now being reduced.

Further, an injection pump lever opener (fuel injection amount control means) 46 is provided for controlling the stopper position of the injection pump lever 17a and controlling the fuel injection amount separately from operation by the accelerator pedal. The injection pump lever opener 46 is constructed as a diaphragm pressure-responsive device. That is, the injection pump lever opener 46 is
An engaging portion 46 that can engage the injection pump lever 17a
A pressure chamber 46c partitioned by the diaphragm 46b has an atmospheric passage 64 that introduces atmospheric pressure Vat through a filter 48.
Vacuum pressure Vvac from vacuum pump 25
It is connected to the vacuum passage 65 that guides the
Each of these passages 64 and 65 is provided with an electromagnetic on-off valve (hereinafter referred to as "electromagnetic valve" as necessary) 47.
and an electromagnetic on-off valve (hereinafter referred to as "electromagnetic valve" as necessary) 47'.

And the solenoid 4 of each electromagnetic valve 47, 47'
When a control signal by duty control is supplied from the ECU 9 to 7a, 47'a, each valve body 47b, 4
7'b is controlled by suction, thereby adjusting the pressure (negative pressure) supplied to the pressure chamber 46c of the injection pump pull lever opener 46.
The rod 46a is appropriately retracted to control the stopper position of the injection pump lever 17a.

A position sensor 66 is also provided to detect the movement of the rod 46a of the injection pump lever opener 46, and the position of the injection pump lever stopper is fed back to the ECU 9 from this position sensor 66.

By the way, the increase ΔQ in the fuel injection amount per one stroke of the injection pump 17 is determined by setting the retardation amount α, and by significantly reducing the thermal efficiency of the engine E, the increase in the average effective pressure is calculated as the effective work of the engine E. It does not appear and is released as heat loss. That is, the total amount of fuel per stroke Q
The amount of heat equivalent to is the sum of the amount of work and heat loss, but here, the amount of heat equivalent to the amount of fuel increase ΔQ is
By setting the retardation amount α, all of the heat is released as heat loss, suppressing the increase or decrease in the amount of work itself. However, the exhaust gas temperature rises due to such heat loss, and incomplete combustion products are oxidized and generated by the catalyst on DPO5. The combustion heat generated increases the exhaust gas temperature.

Therefore, by delaying (retarding) the injection timing and simultaneously increasing the fuel injection amount by operating the accelerator pedal by the driver, the exhaust gas temperature increases and the combustion of the particulate on the DPO5 can be promoted. It is possible to play DPO5.

As shown in FIG.
Internal temperature and DPO outlet exhaust temperature (these temperatures are collectively referred to as "DPO temperature"), pump lever opening from the injection pump lever opening sensor 19,
In addition to inputting the detection signals of the engine rotation speed from the engine rotation speed sensor 20 and the secondary air amount from the position sensor 39, a vehicle speed sensor 42 that detects the vehicle speed, a water temperature sensor 44 that detects the engine cooling water temperature, and the time are input. Each signal from the clock 43 that ticks the clock is input, and after receiving these signals,
The ECU 9 performs the processes described below, and sends control signals suitable for each process to the exhaust introduction solenoid 12a, the exhaust pressure sensor solenoid 11a, the fuel injection timing control means 18, and the intake throttle valve opening control solenoid 27.
a, intake throttle valve closing control solenoid 28a,
In addition to outputting to the EGR valve closing control solenoid 35a, the EGR valve opening control solenoid 36a, the intake pressure sensor solenoid 37a, and the injection pump lever opener solenoids 47a and 47'a,
An output is also provided to a warning lamp 62 that is turned on when a predetermined amount or more of particulate matter accumulates on the DPO 5.

The ECU 9 is configured with a CPU, an input/output interface, or a memory (including a map) such as RAM or ROM, and has a regeneration control means M that controls the operation of the fuel injection timing control means 18.
1. The EGR amount control means M2 that controls the operation of the EGR valve 30, the intake throttle amount control means M3 that controls the operation of the intake throttle valve 21, and the DPO temperature are, for example, 600°C.
solenoid 47 sends a control signal to increase the amount of fuel injected into the diesel engine when the temperature is higher than
a, 47'a, and a control signal for driving the intake throttle valve 21 to the closing side is output to the solenoids 27a, 27'a.
8a, and outputs a control signal for driving the EGR valve 30 to the open side to the solenoids 35a and 36a.

With the above configuration, muffler pressure loss (P ₂ − P ₀ )
After determining whether or not to promote the regeneration of DPO5 based on the information on the DPO pressure drop (P ₁ - P ₂ ), the integrated value information of the engine speed, or the integrated information of the product of the engine speed and the lever opening degree, etc. If it is determined from the above information that DPO regeneration should be promoted because the particulate rate rotation amount is larger than a predetermined value, the injection timing is fully retarded by the regeneration control means M1. .

As a result, the DPO inlet temperature Tin, the DPO internal temperature Tf, and the DPO outlet temperature _T0 rise as shown in FIG.

At this time, the intake throttle valve 20 is operated to appropriately throttle the intake air and reduce the amount of intake air by a predetermined amount, thereby promoting a rise in exhaust gas temperature. Note that the target intake throttle valve opening or target intake pressure is stored in a map according to the engine rotational speed and the pump lever opening.

Furthermore, when the fuel injection timing control means 18 as a regeneration assisting mechanism is operating as described above, EGR is in principle cut off in order to minimize the driving feeling during regeneration.

In this way, as the DPO temperature increases,
The overheating prevention control, which is a feature of this device, performs its function. That is, as shown in Fig. 8, after detecting the DPO temperature in step a1, in step a2,
It is determined whether the DPO temperature is higher than 600°C.

If the DPO temperature is lower than 600°C, the process returns after stopping the process shown in Fig. 8 to continue promoting regeneration, but if the DPO temperature exceeds 600°C, step a3 moves to the target stopper position. Set.

This target stopper position (required pump lever stopper opening degree) is set according to the engine speed, as shown in FIG. 6, and the characteristics shown in FIG. 6 are stored in the map.

For reference, FIG. 5 shows a governor characteristic diagram showing the relationship between the fuel injection amount and pump speed using the injection pump lever opening degree θ as a parameter. The characteristic DPO indicated by symbol A in this figure 5
This shows the minimum injection amount characteristics required at high temperatures.

After that, in step a4, the injection pump lever opener 46 is operated and the injection pump lever 17 is activated.
By increasing the stopper position a by a certain angle, the fuel injection amount during deceleration is increased by a predetermined amount.

Further, in step a5, a target intake throttle amount is set, and then in step a6, the intake throttle valve 21 is controlled to be closed based on this target intake throttle amount.

Note that the target intake throttle amount is set in the map based on the pump lever opening degree and the engine rotation speed.

Also, in step a7, set the target EGR amount,
Next, in step a8, the EGR valve 30 is controlled to open based on this target EGR amount.

Note that the target EGR amount is also set in the map based on the pump lever opening degree and engine rotation speed.

This makes it possible to reduce the excess air ratio and suppress combustion of the particulate, while increasing the exhaust flow rate to increase the amount of heat removed, thereby sufficiently suppressing excessive temperature rise of the DPO5.

In addition, in the above process, first step a3,
After processing steps a5 and a7, step a4, a6,
You may also perform a8 processing.

Thereafter, after detecting the DPO temperature, in step a9, the DPO temperature is determined again in the hope that the excessive temperature rise of DPO5 has been suppressed.

At this step a9, the DPO temperature is still 550.
When the temperature is higher than ℃, the above-mentioned process for suppressing excessive temperature rise of DPO (steps a3 to a8) is continued. As a result of suppressing excessive temperature rise, in step a9,
When the DPO temperature is determined to be below 550℃,
Assuming that the risk of DPO5 melting has disappeared, in steps a10 to a12, the EGR amount is returned to normal control, the intake throttle amount is returned to normal control (in principle, fully open), and the injection pump lever stopper position is changed. Return to original position.

Note that reference numerals 49 and 49' in FIG. 1 indicate water traps (steam/water separators).

Further, as the clock 43, a built-in clock in the ECU 9 may be used.

Additionally, this device uses a diesel particulate collection member (usually referred to as a diesel particulate filter or DPF) that does not have a catalyst.
It can also be applied to this DPF protection device when forced regeneration is performed.

As described in detail above, according to the diesel particulate collection member protection device of the present invention, a diesel engine is installed in the exhaust passage of a diesel engine to collect particulate particulate from the combustion chamber of the diesel engine. A particulate collection member, a regeneration mechanism that can burn particulate collected in the diesel particulate collection member to regenerate the diesel particulate collection member, and control the operation of the regeneration mechanism. a first detection means for detecting the temperature of the diesel particulate collecting member; and a second detection means for detecting the operating state, and in response to the signals from the first and second detection means, the temperature of the diesel particulate collection member is equal to or higher than a predetermined value and the diesel engine is activated. When in a state of deceleration,
The simple structure includes a particulate combustion suppressing means for outputting a control signal for increasing the fuel injection amount to the fuel injection amount control means to the fuel injection amount control means, and the diesel particulate collecting member is likely to be damaged by melting. Under certain conditions, the excess air ratio can be reduced to suppress combustion of particulate matter while increasing the exhaust flow rate to increase the amount of heat removed. The temperature rise during regeneration of the diesel particulate collection member can be suppressed, and this prevents the diesel particulate collection member from melting and the catalyst from deteriorating. This has the advantage that the collection member can be sufficiently protected.

[Brief explanation of the drawing]

The figures show a diesel particulate collection member protection device as an embodiment of the present invention. Fig. 1 is its overall configuration, Fig. 2 is its block diagram, and Fig. 3 is its injection pump lever opener. Figures 4 to 7 are graphs for explaining their functions, Figure 8 is a flow chart showing their control procedure, and Figure 9 is a hydraulic pressure diagram for the fuel injection timing control means. It is a system diagram. 1... Cylinder block, 2... Cylinder head, 3... Intake passage, 4... Exhaust passage, 5... Diesel particulate collection member (DPO), 6
...Muffler, 7...Turbo charger, 8...
Heat retention tube, 9...Electronic control unit (ECU), 10...
Pressure sensor, 11, 12...Solenoid three-way switching valve,
11a, 12a... Solenoid, 13... Air filter, 14-16... Temperature sensor forming the first detection means, 17... Injection pump, 17a... Injection pump lever, 18... Fuel injection forming the regeneration mechanism. Timing control means, 18a... timer piston, 18b... solenoid valve for solenoid timer, 18c... retard valve, 19... second
Injection pump lever opening sensor constituting the detection means, 20...engine rotation speed sensor, 21...intake throttle valve, 22...pressure response device, 22a...rod, 22b...diaphragm, 22c...pressure chamber, 23...Air filter, 24...Atmospheric passage,
25... Vacuum pump, 26... Vacuum passage, 27, 28... Solenoid valve, 27a, 28a...
... Solenoid, 27b, 28b... Valve body, 29...
... EGR passage, 30... EGR valve, 31... Pressure response device, 31a... Rod, 31b... Diaphragm, 31c... Pressure chamber, 32... Air filter, 33... Atmospheric passage, 34... Vacuum passage, 35-37...Solenoid valve, 35a, 36a, 3
7a...Solenoid, 35b, 36b, 37b...
... Valve body, 38 ... Pressure sensor, 39 ... Position sensor, 40 ... Passage, 41 ... Air filter, 42 ... Vehicle speed sensor, 43 ... Clock, 4
4... Water temperature sensor, 45... Potentiometer,
46... Injection pump lever opener (fuel injection amount control means), 46a... Rod, 46b... Diaphragm, 46c... Pressure chamber, 46d... Engaging portion, 47, 47'... Solenoid valve, 47a, 47 'a...
...Solenoid, 47b, 47'b...Valve body, 48
...Air filter, 49,49'...Water trap, 50,51...Oil passage, 52-54...Orifice, 55...Check valve, 56...Regulating valve, 57...Feed pump, 58...Pump Chamber, 59...Plungeer, 6
0... Delivery valve, 61... Nozzle, 62...
...warning lamp, 63...accelerator wire, 64...atmospheric passage, 65...vacuum passage, 66...potentiometer, E...diesel engine, M1...regeneration control means, M2...
EGR amount control means, M3... intake throttle amount control means,
M4...Pateikulate combustion suppression means.

Claims (1)

[Claims] 1 In a diesel engine, there is a diesel particulate collection member disposed in the exhaust passage of the diesel engine to collect particulate matter from the combustion chamber of the diesel engine, and particulate matter collected by the diesel particulate particulate collection member. a regeneration mechanism capable of regenerating the diesel particulate collecting member by burning it; a regeneration control means controlling the operation of the regeneration mechanism; and a fuel injection amount control means capable of controlling the amount of fuel injected into the diesel engine. a first detection means for detecting the temperature of the diesel particulate collection member; and a second detection means for detecting the operating state of the diesel engine.
a detection means, and when the temperature of the diesel particulate collection member is above a predetermined value and the diesel engine is in a deceleration state in response to signals from the first and second detection means, A diesel particulate collection member protection device, comprising particulate combustion suppressing means for outputting a control signal for increasing the amount of fuel injected into the diesel engine to the fuel injection amount control means.