KR100277092B1 - How to promote catalyst activation - Google Patents

Abstract

The present invention increases the exhaust heat while the unburned mixer is naturally combusted in the exhaust system while the engine is driven by the remaining two cylinders while the idle operation is greatly increased while the idle intake air amount is greatly increased during cold start. The present invention relates to a method for promoting catalyst activation to achieve the above object.

Checking whether the engine cooling water temperature WT is equal to or less than a predetermined value WTO immediately after starting (S1 to S3);

If the idle state increases the idle air amount by a predetermined amount (S4);

Sequentially stopping ignition in the cylinder (S5);

Reducing the fuel injection amount to the cylinder in which the ignition is stopped (S6);

It is characterized in that it is performed as a step (S7) to check whether the coolant temperature is below a predetermined value, and if it is checked below, it is returned to the previous step and re-executed.

Description

How to promote catalyst activation

The present invention relates to a catalyst activation promoting method that enables the catalyst purification operation during cold start to be performed early.

In general, the catalyst is mounted on the exhaust system of the engine to oxidize or reduce the exhaust gas passed by the exhaust heat of a constant temperature combusted in the engine so as to be purified, so that air pollution by the exhaust gas can be prevented.

On the other hand, the catalyst has to be heated to a constant temperature in order to have an exhaust purification function, so the exhaust temperature is formed at the beginning of the start-up so that the purifying function is performed only after a certain time has elapsed.

In order to prevent such a delay in the purification of the catalyst, shortening of the catalyst activation time is the most effective method. For this purpose, a widely used method together with the EHC (Electrically Heater Cata1yst) method, in which the catalyst is heated by force electronically, is used. Same way as in FIG.

In other words, the secondary air valve (3) for supplying air to the exhaust pipe (2) on the front side of the catalyst (1) is mounted, and the fuel injection injector (4) is mounted on one side of the catalyst (1) during cold start As the air and fuel are injected at the same time, it is caused to be burned by a separately installed spark plug or its own exhaust heat so that the exhaust temperature induced by the catalyst 1 is rapidly increased.

By improving the exhaust temperature, the catalyst 1 is activated more quickly and performs the exhaust purification operation early.

However, the exhaust purification operation during the cold start by the above structure has a problem in that the operation structure is very complicated to be formed, which not only is disadvantageous to the engine layout but also increases the manufacturing cost and increases the burden.

Accordingly, the present invention is to compensate for the correction in view of the above problems, the present invention is to allow the idle intake air amount is greatly increased during the cold start while the two cylinders to prevent the combustion action is performed by the remaining two cylinders by the combustion action It is an object of the present invention to provide a method for promoting catalyst activation which allows an unburned mixer to naturally burn in an exhaust system while driving an engine, thereby increasing exhaust heat.

The present invention to achieve the above object

Checking whether the engine coolant temperature is in an idle state immediately after starting, if it is checked below a predetermined value;

Allowing the idle air amount to increase by a certain amount if the idle state;

Causing the ignition in the cylinder to stop every other order;

Reducing the amount of fuel injected into the cylinder where the ignition is stopped;

If the cooling water temperature is below a predetermined value, the following checks are returned to the previous step and is re-executed. If the check is abnormal, the control is terminated and the idle driving is performed.

1 is a control flowchart according to the present invention.

2 is an accelerated structure diagram for conventional catalyst activation.

Referring to this in more detail with reference to the accompanying drawings, Figure 1 shows a control flow according to the present invention, the present invention is a control method to be performed during cold start.

That is, the engine coolant temperature (WT) is checked immediately after starting (S1), and the coolant temperature (WT) at this time is compared with a preset value (WTO) input to the electronic controller (S2), and the compared coolant temperature (WT). If it is determined that is smaller than the set value (WTO) it is checked whether the idle driving state (S3).

When the driving state checked in this state is in the idle state, the Idle Speed Control Acutator (ISA) is immediately activated to increase the idle air amount (S4), and the ignition is stopped in the cylinder driven in a sequential order (S5), and at the same time, the ignition is stopped. The amount of fuel injected into the cylinder is adjusted to be reduced (S6).

After the fuel loss adjustment, the cooling water temperature (WT) is checked again (S7), if it is continuously checked to be smaller than the set value (WTO), and returned to the step of checking whether it is in the idle state of the previous stage, and if it is checked to be larger than the set value (WTO), the control is performed. Will be terminated.

On the other hand, after the fuel injection amount is reduced in the control process (S6), instead of checking the cooling water temperature (WT) as described above, the temperature checked by the exhaust temperature sensor which is unconditionally passed by a predetermined time or separately installed by the exhaust pipe in front of the catalyst. Control may be terminated by determining whether is checked above a certain temperature.

As described above, the present invention can greatly improve the exhaust purification during cold startup, which is the most vulnerable to exhaust gas control, by promoting the activation of the catalyst while maintaining the driving force only by two cylinders instead of greatly increasing the intake air amount during cold startup. Will be.

Therefore, the control according to the present invention has a very useful effect of reducing the fuel consumption during cold start and further promoting the activation of the catalyst, thereby improving the reliability while actively responding to the recently tightened exhaust gas regulations worldwide. Will be.

Claims (2)

Checking whether the engine cooling water temperature (WT) is below the predetermined value (WTO) immediately after starting and being in an idle state (S1-S3); If the idle state increases the idle air amount by a predetermined amount (S4); Sequentially stopping ignition in the cylinder (S5); Reducing the fuel injection amount to the cylinder in which the ignition is stopped (S6); Checking whether the cooling water temperature is equal to or lower than a predetermined value, and if it is checked below, the process returns to the previous stage and is executed again; Determining whether the temperature checked from the exhaust temperature sensor mounted on the exhaust pipe in front of the catalyst is checked above a predetermined temperature after performing step S6 of reducing the fuel injection amount so as to terminate the control; A method for promoting catalyst activation, characterized in that it is carried out as. The method of claim 1, wherein after the step (S6) of reducing the fuel injection amount is unconditionally checked, a check is made to determine whether a predetermined time has elapsed and the control is terminated.