Claims:We Claim:

1. A method of dosing an additive for cleaning a nozzle in an injector, the method comprising:
sensing a speed of an engine by a speed sensor;
calculating a torque from the sensed speed of the engine by an electronic control unit;
comparing the calculated torque with a predefined torque value by the electronic control unit;
dosing of additive through the nozzle in the injector by the electronic control unit, if the calculated torque is less than the predefined torque value.

2. The method of dosing an additive as claimed in Claim 1, wherein the speed sensor is a toothed wheel.

3. An electronic control unit for enabling dosing an additive for cleaning a nozzle in an injector, the control unit adapted to:
calculate a torque from a speed of an engine sensed by a speed sensor;
compare the calculated torque with a predefined torque value stored in the control unit;
control dosing of additive through the nozzle in the injector, if the calculated torque is less than the predefined torque value.

4. A method of dosing a catalyst in a diesel particulate filter in an exhaust of a vehicle, the method comprising:
sensing a delta pressure across the diesel particulate filter by a delta pressure sensor;
comparing the sensed delta pressure with a predefined delta pressure value by an electronic control unit;
dosing of catalyst to the diesel particulate filter, if the sensed delta pressure is greater than the predefined delta pressure value.

5. An electronic control unit for enabling dosing a catalyst in a diesel particulate filter in an exhaust of a vehicle, the control unit adapted to:
compare a sensed delta pressure with a predefined delta pressure value stored in the control unit; and
control dosing a catalyst to the diesel particulate filter, if the sensed delta pressure is greater than the predefined delta pressure value.

, Description:Complete Specification:

The following specification describes and ascertains the nature of this invention and the manner in which it is to be performed.

Field of the invention
[0001] This invention relates to a method and a control unit for enabling dosing an additive for cleaning a nozzle and catalyst for a diesel particulate filter.

Background of the invention
[0002] Additives in the fuel are used in passenger and commercial vehicles, which need to be dosed regularly. Catalyst also needs to be dosed in the diesel particulate filter for passive regeneration. Dosing always or at regular intervals results in the wastage of additives or catalyst or using additives or catalysts whenever it is not needed. Dosing intermittently or infrequently results in the problem of dosing the additive or catalyst whenever the additive or catalyst is not required. There is a need to dose the additive or catalyst whenever it is required.

Brief description of the accompanying drawing
[0003] Figure 1 shows method steps for a method of dosing an additive for cleaning a nozzle; and

[0004] Figure 2 shows method steps for a method of dosing a catalyst in a diesel particulate filter in an exhaust.

Detailed description of the embodiments
[0005] Figure 1 shows method steps for a method 10 of dosing an additive for cleaning a nozzle. The method 10 comprises a first step 105 of sensing a speed of an engine by a speed sensor, a second step 110 of calculating a torque from the sensed speed of the engine by an electronic control unit, a third step 115 of comparing the calculated torque with a predefined torque value by the electronic control unit, and a fourth step 120 of dosing an additive through the nozzle in the injector by the electronic control unit, if the calculated torque is less than the predefined torque value. The speed sensor can be a toothed wheel sensor attached to the engine, which is understood in the art.

[0006] The electronic control unit for enabling dosing an additive for cleaning the nozzle in the injector, the control unit adapted to calculate torque from the speed of the engine sensed by the speed sensor, compare the calculated torque with the predefined torque value stored in the control unit and control dosing of additive through the nozzle in the injector, if the calculated torque is less than the predefined torque value.

[0007] The objective of the first aspect of the invention is to dose the additive for cleaning the nozzle in the injector. So when the torque is calculated from the sensed speed and the torque is below the predefined torque value, then the additive is dosed to clean the nozzle of the injector. The dosing of the additive is done into the fuel. The dosing of the additive in the injector nozzle is to clean the nozzle. The nozzle of the injector that is blocked can cause less fuel to be sprayed and thereby less torque to be generated. So, based on the torque value, the additive is dosed to clean the nozzles, so that the torque can be restored to the normal range.

[0008] Figure 2 shows method steps for a method 20 of dosing a catalyst in a diesel particulate filter in an exhaust. The method 20 comprises a first step 205 of sensing a delta pressure across the diesel particulate filter by a delta pressure sensor, a second step 210 of comparing the sensed delta pressure with a predefined delta pressure value by an electronic control unit and a third step 215 of dosing a catalyst to the diesel particulate filter, if the sensed delta pressure is greater than the predefined delta pressure value.
[0009] The electronic control unit for enabling dosing the catalyst in the diesel particulate filter in the exhaust of the vehicle, wherein the control unit is adapted to compare sensed delta pressure with the predefined delta pressure value stored in the control unit and control dosing the catalyst to the diesel particulate filter, if the sensed delta pressure is greater than the predefined delta pressure value.

[0010] The objective of the second aspect of the invention is to dose the catalyst for passive regeneration of the diesel particulate filter. If the diesel particulate filter is clogged, the delta pressure measured across the diesel particulate filter is high. Hence, if the measured delta pressure is higher than the predefined or threshold level, then the control unit doses the catalyst such that passive regeneration can happen at normal exhaust temperature. When regeneration happens and the clogging is removed, the delta pressure comes back to the normal range and therefore the dosing of the catalyst by the control unit is stopped.

[0011] The advantages of the above invention is that the additive and the catalyst is dosed whenever it is required, without any wastage.

[0012] ‘Adapted’ or ‘arranged’, in the context of the instant disclosure, refers to the technical capability or the technical capacity of a component, in relation to which the term ‘adapted’ or ‘arranged’ is used, to carry out or executed a specified action or actions, upon the requirement of the specified action or actions to be carried out or executed. Moreover, the usage of the term ‘adapted’ or ‘arranged’ here, is in reference with the normal technical capability or technical capacity of the component, imparted by the design or the structure or the composition of the component, and not in reference with any special or extraneous capability or capacity, beyond the scope of the normal technical capability or technical capacity. Therefore there is a need to address this problem.
[0013] It should be understood that embodiments explained in the description above are only illustrative and do not limit the scope of this invention. Many such embodiments and other modifications and changes in the embodiment explained in the description are envisaged. The scope of the invention is only limited by the scope of the claims.