JPH0330407B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for regenerating particle collectors for diesel engines used in vehicles such as automobiles.

It has long been known to provide a particle collector in the exhaust system of a diesel engine to capture combustible particles such as carbon particles in the exhaust gas and prevent them from being released into the atmosphere. .

The particle collector has a heat-resistant collection material, and as the amount of collected particles (collected matter) increases, this material will become clogged and interfere with normal exhaust gas flow. become. Therefore, in order for the particle repair device to be used without interfering with the normal exhaust gas flow, the particles trapped in the particle collector must be periodically removed and the particle collector must be regenerated. needs to be done.

One method for regenerating this particle collector is to arrange an electric heater on the upstream end face of the particle collector and the collection material, and to energize the electric heater. A method is known in which the collected matter collected by the collecting material is incinerated and incinerated by heat generation. In vehicles such as automobiles, electric power is supplied to the electric heater using a battery, and the electric power consumption of this electric heater is quite large. Therefore, if the electric heater is energized to regenerate the particle collector when the voltage of the battery is below the rated voltage or is considerably low, the voltage of the battery will drop excessively, causing what is called a battery rise. There is a possibility that a situation may occur.

The present invention provides a regeneration method that detects the voltage of the battery that is the power source of the electric heater, controls the energization of the electric heater according to the detected voltage, and regenerates the particle collector without causing the battery to run out. is intended to provide.

According to the present invention, this object is to provide a method for regenerating a particle collector in which a plurality of electric heater elements that are operated by being supplied with current from a battery are disposed on the upstream end surface of a collection material, When a predetermined regeneration time arrives, the voltage of the battery is detected, and when the voltage is between a first predetermined value and a second predetermined value larger than the first predetermined value, the plurality of electric heater elements are activated. This is achieved by a method for regenerating a particle collector, characterized in that the electric heater elements are sequentially energized in a divided manner, and when the voltage is equal to or higher than the second predetermined value, the plurality of electric heater elements are energized all at once. Ru.

When the battery voltage is between the first predetermined value and the second predetermined value, for example, if it is slightly lower than the rated voltage, the power consumption of the battery is reduced by sequentially energizing each of the plurality of electric heater elements. This can be kept small and the occurrence of battery build-up can be avoided.

When the battery voltage is higher than the second predetermined value, for example when it is at the rated voltage, there is sufficient power in the battery, so multiple electric heater elements are energized all at once, without causing the battery to run out.
Regeneration of the particle collector occurs quickly.

The invention will now be described in detail by way of example embodiments with reference to the accompanying drawings.

Fig. 1 is a half-sectional view showing one embodiment of a particle collector in which the regeneration method according to the present invention is carried out, Fig. 2 is a sectional view taken along the line - in Fig.
FIG. 3 is an end view of the upstream end of the filter element of the particle collector shown in FIGS. In these figures, 1 indicates the casing of the particle collector. The casing 1 has an exhaust gas inlet 2 and a connecting flange 3 at one end, and an exhaust gas outlet 4 and a connecting flange 5 at the other end, and is installed in the middle of an exhaust passage of a diesel engine.
The casing 1 has an exhaust gas inlet 2 and an exhaust gas outlet 4
A filter element 6, which is a particle collection material, is housed between the two. The filter element 6 is made of a heat-resistant material such as honeycomb-shaped ceramics, and has an elliptical cross section in this embodiment. A plurality of electric heater elements 8 ₁ to 8 ₈ , eight in this embodiment, are distributed on the upstream end face of the filter element 6 . Of these eight electric heater elements, electric heaters 8 ₁ and 8 ₂ , 8 ₃ and 8 ₄ , 8 ₅ and 8 ₆ ,
8 ₇ and 8 ₈ are arranged symmetrically in pairs with the center of the upstream end face of the filter element 6 as the point of symmetry, and each of these electric heater elements has an individual connection terminal 9 ₁ to 9 at one end thereof. 9 ₈ and is commonly grounded to the grounding element 10 at the other end. Electric heater elements 8 ₁ to 8 ₈ are filter elements 6
The filter element 7 is held between the filter element 7 and the honeycomb-shaped ceramic filter element 7 provided on the upstream side.

As shown in FIG. 4, electric current is selectively supplied to the electric heater elements 8 ₁ to 8 ₈ by the battery 12 via the switches _{11 1 to} 11 ₈ , respectively _. Control device 13 opens and closes
This is done by

The control device 13 is given information regarding the rotation speed of the diesel engine by the engine rotation speed sensor 14 and information regarding the voltage of the battery 12 by the battery voltage detection means 15, and when the integrated value of the engine rotation speed reaches a predetermined value or more, particles are detected. It is determined that it is time to regenerate the collector, and the switches 11 ₁ to 11 ₈ are opened and closed according to the voltage of the battery 12 at this time.
Control is performed according to a flowchart as shown in the figure.

Next, with reference to the flowchart shown in FIG. 5, the procedure for implementing the method for regenerating a particle collector according to the present invention will be explained. First, in step 1, it is determined whether it is time to regenerate the particle collector. In this embodiment, the regeneration timing of the particle collector is determined based on the integrated value of the number of revolutions of the diesel engine. If it is not the regeneration period in step 1, the process advances to step 5, and in this step, all the switches 11 ₁ to 11 ₈ are maintained in an open state, and the electric heater elements 8 ₁ to 8 ₈ are not energized. Not done.

In step 1, when it is time to regenerate the particle collector, the process advances to step 2, in which the voltage V of the battery 12 is read.

Next, the process advances to step 3, in which it is determined whether the battery power supply V is greater than or equal to a predetermined value A. For example, if the rated voltage of the battery 12 is 12V, in step 3 it is determined whether the battery voltage V is 10V or more. When V≧A, that is, when the battery voltage is less than 10V, proceed to step 5, and switch 1 to avoid battery rise.
All of the electric heater elements 1 ₁ to 11 ₈ are maintained in an open state, and all of the electric heater elements 8 ₁ to 8 ₈ are not energized.

When V≧A, that is, the battery voltage is 10V
If this is the case, the process proceeds to step 4, in which it is determined whether the battery voltage V is greater than or equal to a predetermined value B, which is greater than the predetermined value A.
This predetermined value B corresponds to the rated voltage of the battery 12.

When V≧B is not the case, that is, the battery voltage is 10V.
However, if the rated voltage is less than 12V, proceed to step 6. In step 6, the switch 11 ₁ is first closed for a predetermined time, and the switch 11 ₁ is closed for a predetermined period of time.
After the switch 112 is opened, the switch ₁₁₂ is closed for a predetermined time, and in the same manner, the switches ₁₁₃ to ₁₁₈ are sequentially closed for a predetermined time. As a result, first, the electric heater element 8 ₁ is energized for a predetermined time, and after the electric heater element 8 ₁ is energized, the electric heater element 8 ₂ is energized for a predetermined time, and the same goes for the 8 . From ₃ to 8 ₈ , electricity is sequentially applied only for a predetermined period of time. That is, divided energization is performed. In this way, the particle collector is regenerated by sequentially dividing and energizing each of the electric heater elements 8 ₁ to 8 ₈ . In this case, the power consumption of the battery 12 is the rated power of one electric heater element, so it is relatively low and no battery rise occurs.

When V≧B, that is, when the battery voltage is higher than the rated voltage, the process proceeds to step 8, in which all switches 11 ₁ to 11 ₈ are closed at the same time. As a result, the electric heater element 8
₁ to 8 ₈ are energized all at once, thereby quickly regenerating the particle collector. When the voltage of the battery 12 is at the rated voltage, there is sufficient power in the battery, so at this time, even if all the plurality of electric heater elements are energized at the same time as described above, battery rise will occur. There is no.

Although the present invention has been described in detail with respect to specific embodiments above, it will be understood by those skilled in the art that the present invention is not limited to these and that various embodiments can be made within the scope of the present invention. It should be obvious.

[Brief explanation of the drawing]

FIG. 1 is a half-sectional view showing an embodiment of a particle collector used in the method for regenerating an engine particle collector according to the present invention, and FIG. 2 is a sectional view taken along the line - in FIG. 1. FIG. 3 is an end view showing the upstream end face of the filter element of the particle collector shown in FIGS. 1 and 2, and FIG. 4 is an end view of the particle collector shown in FIGS. 1 to 3. FIG. 5 is a flowchart illustrating the procedure for regenerating a particle collector according to the present invention. 1...Casing, 2...Exhaust gas inlet, 3...
...Connection flange, 4...Exhaust gas outlet, 5...
...Connection flange part, 6,7...Filter element,
8 ₁ - 8 ₈ ... Electric heater element, 9 ₁ - 9 ₈ ... Connection terminal, 10 ... Earth element, 11 ₁ - 11 ₈ ...
Switch, 12...Battery, 13...Control device, 14...Engine speed sensor, 15...Battery voltage sensor.

Claims (1)

[Claims] 1. A method for regenerating a particle collector in which a plurality of electric heater elements that are operated by supplying current from a battery to the upstream end of the collection material is provided, and a predetermined regeneration time has arrived. When the voltage of the battery is detected, and when the voltage is between a first predetermined value and a second predetermined value larger than the first predetermined value, energization is sequentially dividedly applied to each of the plurality of electric heater elements, and the voltage is is equal to or greater than the second predetermined value, the plurality of electric heater elements are energized all at once.