JPS62228817A - Burner igniting method for exhaust device - Google Patents

Abstract

PURPOSE:To enable rapid ignition of a burner without decreasing the heat generating temperature of a glow plug, by a method wherein an intermittent and small amount of fuel is injected through an injector toward the glow plug, and subsequently an injection amount is increased to a given value to ignite fuel. CONSTITUTION:When a filter 1 situated in an exhaust gas line catches fine particles and is brought into a given clogged state, a glow plug 3 is ignited, and fuel is fed through an injector 4 to ignite and burn the fuel by means of the glow plug 3. In which case, atmosphere is increased in temperature, the fine particles caught by the filter 1 are ignited for burn-off to unclog the filter 1. When fuel is injected to the ignited glow plug 3, an intermittent small amount of fuel, i.e., the fuel in an amount of 50% of a given amount is injected toward the glow plug at a time or in several lots at intervals of a specified time. When a given amount of the fuel is fed, flame is generated to apply heat to atmosphere.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present application relates to burner ignition in an exhaust treatment device that captures particulates discharged from a diesel engine with a filter and heats and burns them out with a burner to regenerate the filter. Regarding the method.

[Conventional technology]

As shown in, for example, Japanese Utility Model Application No. 60-58815, an exhaust treatment device for a diesel engine includes a heat-resistant filter installed in the exhaust pipe, and a fuel burner consisting of a fuel supply section and a glow plug installed in front of the filter. It has a structure with In such a device, the fine particles, mainly composed of carbon particles, captured by the filter are heated and incinerated by a fuel burner. the result,
The filter is regenerated. The fuel burner is ignited as follows. That is, in this method, a glow plug is ignited, and fuel is continuously injected into the glow plug from a fuel supply section in the form of small droplets or mist, and the fuel is ignited.

Fuel is supplied in an amount sufficient to obtain a predetermined high temperature.

[Problem that the invention seeks to solve]

In the above conventional ignition method, the fuel from the fuel supply unit collides with and adheres to the glow plug, and the glow plug is cooled, resulting in a drawback that the ignitability of the fuel is poor. Incineration of the captured particulates requires a high-temperature atmosphere, which requires a relatively large amount of fuel to be continuously supplied, and as a result, the temperature of the glow plug increases slowly.

[Means for solving problems]

A small amount of fuel is intermittently injected from the injector toward the glow plug, and then the injection amount is increased to a predetermined value to ignite the fuel.

[Effect]

The amount of fuel that collides and adheres to one glow plug is small and intermittent, and does not cool the glow plug extremely. Furthermore, since the amount of fuel attached is small, there is little heat absorption during evaporation.

〔Example〕

An embodiment of the burner ignition method will be described using the illustrated device (d). and an injector 4 for fuel supply. 5 is a temperature sensor, and 6 is a control unit. A secondary air supply pipe 7 and an exhaust pipe 8 are connected to the burner device fi2. .

When the filter 1 captures particulates and reaches a predetermined clogging state, the glow plug 3 is ignited, fuel is supplied from the injector 4, and the glow plug 3 ignites and burns the fuel.

This causes the atmosphere to rise in temperature and ignite the particulates captured by the filter 1. Burn it down. When the particulates are burned away, the clogged condition of the filter 1 is cleared and the filter 1 is regenerated.

Next, to explain the ignition method of the present invention, when injecting fuel to the ignited glow plug 3, first, as shown in FIG. 2, a small amount of fuel is intermittently supplied to the glow plug 3, Next, there is a method of supplying m, that is, a predetermined amount of fuel necessary to obtain a predetermined high temperature. Here, intermittent means to supply fuel once or several times at predetermined time intervals, and a small amount refers to 1 of 50% of the predetermined amount of fuel in the example. .

The transition from intermittent fuel supply to fixed amount fuel supply is the second
As shown in the figure, how to increase the amount of fuel immediately (graph a),
Alternatively, the dose may be gradually increased.

The values of the predetermined amount, small amount, and number of fuel injections are determined experimentally according to the specifications of the exhaust treatment device.

When small amounts of fuel are intermittently supplied to the glow plug, the fuel ignites. Then, when a predetermined amount of fuel is supplied, a flame is generated and heats the atmosphere.

〔effect〕

At the time of fuel ignition, the fuel supplied to the glow plug is intermittent and small, and does not cool the glow plug, so the heat generation temperature of the glow plug does not decrease, resulting in prompt ignition.

[Brief explanation of drawings]

FIG. 1 is a sectional view of an exhaust treatment device to which the present invention is applied;
FIG. 2 is a diagram showing changes in fuel supply amount according to the method of the present invention. 1... Filter 2... Burner device 3... Glow plug 4... Cleaning port in injector drawing (no change in content) Between one branch and TFT -→ Amendment 2 Procedures (Method) July 1986
Month lz day 1, case indication 1985 patent application No. 73226 2, name of invention burner ignition method for exhaust treatment device 3, person making the amendment Relationship to the case Patent applicant postal code 170. Telephone: 03-'189-8484
June 4, 1986 (shipment date June 24, 1986) 5
, hQ positive vs.

Claims (1)

[Claims] A burner ignition method for an exhaust treatment device in which a small amount of fuel is intermittently injected from an injector toward a glow plug, and then the injection amount is increased to a predetermined value to ignite the fuel.