JPS59158309A - Regenerative burner controller for micro exhaust particle catching trap for internal-combustion engine - Google Patents

Abstract

PURPOSE:To obtain a burner controller having good firing performance and durability by constructing such that prior to fuel supply to burner, a fuel supply starting signal is fed to fuel feeding means of burner when the temperature of glow plug has exceeded over predetermined level. CONSTITUTION:Upon provision of regeneration starting signal from trap 3 choking detecting means, power is fed through a controller 11 to the heater wire of glow plug 7. When the temperature of glow plug 7 has reached to such level as sufficient for firing, a fuel pump 10 and injection valve 8 will start operation to feed fuel to a burner 4. Since the glow plug 7 is heated sufficiently, fuel to be fed to the burner 4 will be fired reliably to burn while consuming excessive oxygen in exhaust gas to produce high temperature gas which will heat and burn micro particles in exhaust gas thus to regenerate the trap 3.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a control device for a burner for regenerating an exhaust particulate collection trap used as an exhaust gas purification device for an internal combustion engine. It relates to means for supplying fuel.

A conventional exhaust purification device for an internal combustion engine for an automobile is disclosed in, for example, Japanese Patent Application Laid-open No. 115809/1983. This is a device that installs a trap in the middle of the exhaust passage to collect particulates whose main component is carbon in the exhaust gas, and also uses a trap regeneration burner to incinerate the particulates collected in the trap. It detects the collection state of the trap based on the differential pressure between the inlet side pressure and the outlet side pressure of the trap, determines whether regeneration is necessary, and operates the burner for a predetermined period of time if regeneration is required. It is designed to allow

However, with this type, when it is determined that the trap needs regeneration, electricity is energized to the glow plug and fuel is supplied to the burner at the same time, so the fuel is supplied to the burner during the period after energization until the glow plug becomes red hot. Unburned fuel is discharged from the burner and deposits on the glow plug and the exhaust system downstream of the burner. The fuel adhering to the glow plug cools the glow plug, prolongs the time it takes for the glow plug to become red hot, and worsens the ignitability of the burner. The fuel adhering to the exhaust system is ignited and burned by the heat held by the exhaust system or by the flame of the burner that ignites after the glow plug becomes red hot, overheating the exhaust system including the burner and glow plug, or causing the trap to burn out. and deteriorate their durability.

The present invention has been made in view of these conventional problems, and includes a temperature sensor that detects the temperature of the glow plug that operates prior to fuel supply to the burner, and a temperature sensor that detects the temperature of the glow plug that operates before fuel is supplied to the burner. It is an object of the present invention to solve the above-mentioned inconvenience by providing means for issuing a fuel supply start signal to the burner fuel supply device at the same time, and starting fuel supply to the burner after confirming red heat of the glow plug. .

The present invention will be explained below based on an embodiment shown in FIG.

That is, as shown in the figure, a trap case 2 is interposed in the middle of an exhaust passage 1 of a tasel engine, and a honeycomb type trap 3 is installed inside the trap case 2. This trap 3 - Some of the holes in the honeycomb are opened on the inlet side and the outlet side is closed, and the other portions are closed on the inlet side and the outlet side is opened, so that when the exhaust gas passes through the wall of the hole, This is used to collect fine particles.

A burner 4 for trap regeneration is provided upstream of this trap 3, and this burner 4 includes a backflow type evaporator 5 having a flame jet port 5a, a fuel conduit 6 facing into the backflow type evaporator, and a backflow type evaporator. 5 and a glow plug 7 for ignition facing near the flame outlet 5a.

An electromagnetic fuel injection valve (fuel injector) 8 is provided at the entrance of the fuel conduit 6, and the fuel injection valve 8 is supplied with fuel (same as engine fuel, for example) from a fuel tank 9 by an electromagnetic fuel pump 10. light oil) is being introduced.

Therefore, the burner 4 is operated by operating the fuel pump 10, the fuel injection valve 8, and the glow plug 7 as fuel supply means.

The driving of the fuel pump 10 and the fuel injection valve 8 and the energization of the Kiglow plug 70 are performed by a signal current issued from the control device 11.

This control device 11 operates the glow plug γ when receiving a regeneration start signal from a trap 30 clogged state detection means (not shown), and after confirming that the glow plug γ is red hot, the fuel pump 10 and the fuel injection valve 8, and its specific configuration is shown in FIG. That is, in the figure, the input terminal of the amplifier 11a is connected to lead #7 of a thermocouple 7b as a temperature sensor provided near the heater wire 7a of the glow plug 7 shown in FIG.
C is connected.

The electromotive force generated in the thermocouple 7b by heating the heater wire 7a is amplified by the amplifier 118 and then input to the comparator 11b.
It is compared with the preset voltage input to 1b. This preset voltage is set in accordance with the electromotive force generated in the thermocouple 7b when the glow plug 7 reaches a temperature that reliably ignites the burner 4. Then, the comparator 11b sends a glow plug red-hot confirmation signal to the controller 11e when the output/voltage of the amplifier 11a becomes higher than the preset voltage. Conversely, the output voltage of the amplifier 11B or the predetermined Bricella)! When both the pressure and the pressure are low, the comparator 11b does not generate any signal.

This controller 11 (!U) has a function of operating the fuel pump 10 and fuel injection valve 8 when it receives a glow plug red heat confirmation signal from the comparator 11b, and has a function of energizing the glow plug 7 when it receives a regeneration start signal. Specifically, it is composed of a microcomputer.

Note that the battery 12 is used as a power source to operate the control device 11 and drive the fuel pump 10 and fuel injection valve 8.

Next, the action will be explained.

In the exhaust particulate processing device having such a configuration, when a regeneration start signal is issued from the clog detection means of the trap 3 (not shown), the signal is input to the controller 11c of the control device 11, and the controller 11e Electricity starts to be applied to the heater wire 7a of the glow plug 7.

The voltage generated in the pair 7b due to heating of the glow plug T is amplified by the amplifier 11&, and compared with the preset voltage set to the predetermined value by the comparator 11b. Here, the output voltage of the amplifier 11a is the precera) [
When the pressure increases, that is, when the temperature of the glow plug 7 exceeds the temperature at which the fuel is reliably ignited, the comparator 11b issues a glow plug red heat confirmation signal to the controller 11c. When the controller 11c receives this signal, it operates the fuel pump 10 and the fuel injection valve 8 to start supplying fuel to the burner 4.

Here, the glow plug 7 is heated to a sufficiently high temperature,
Since the fuel is red-hot, the fuel supplied to the burner 4 is reliably ignited and burns while consuming excess oxygen in the exhaust gas to generate high-temperature gas. This high-temperature gas is guided to the trap 3, where the exhaust particulates are heated and burned to regenerate the trap 3.

Here, the temperature sensor 13 installed upstream of the trap 3 detects the temperature of the exhaust gas guided to the wrap 3, and when the temperature reaches 500°C or higher, it is determined that the burner 4 has ignited and the glow is emitted. The power to plug T is stopped.

Note that the regeneration of the trap 3 is stopped after a predetermined period of time has elapsed after the ignition of the burner 4 is confirmed.

As explained above, in the present invention, fuel is supplied to the burner after confirming that the glow plug is red hot.
Jiglow lag commuting due to exhaust temperature and battery voltage,
Even if the time until it becomes red hot changes, the burner is always reliably ignited, improving the ignitability of the shibana. In addition, this prevents unburned fuel from being released into the exhaust system and adheres to it, and avoids overheating of the exhaust system including the burner and glow plug due to its combustion, and avoids burnout of the trap, thereby reducing the durability of these parts. This will improve sexual performance.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of the present invention, FIG. 2 is a block circuit diagram of essential parts of the control device, and FIG. 3 is a partial sectional view of the glow plug in FIG. 2. 1... Exhaust passage 3... Trap 4... Burner 7... Glow plug 7a... Heater wire
7b...Thermocouple (temperature sensor) 8...Fuel injection valve (fuel supply means) 10...Fuel pump (fuel supply means) 11...Control device 11a...Amplifier
11b... Comparator 11e... Controller patent Applicant Nissan Motor Co., Ltd. Agent Patent attorney Fujio Sasashima

Claims (1)

[Claims] In an internal combustion engine comprising a trap provided in an exhaust passage to collect particulates in exhaust gas, and a trap regeneration burner for incinerating particulates collected in the trap, the internal combustion engine is activated prior to supplying fuel to the burner. An exhaust particulate trap for an internal combustion engine, characterized in that a temperature sensor for detecting the temperature of a glow plug is provided, and a means for issuing a fuel supply start signal to a fuel supply means of a burner when the temperature reaches a predetermined value or more is provided. Control device for regeneration burner of collection trap.