DE102009001453B4 - Glow plug control device and glow plug control system - Google Patents

Abstract

A glow plug control apparatus applied to an internal combustion engine (10) having glow plugs (20) mounted in combustion chambers (15) of the internal combustion engine and a filter device (19a) for trapping particulates in exhaust gases, the glow plug control device characterized by: regeneration activating means (44; 35A) for controllably switching on an electric load such that an electric load of a battery (21) charged by the internal combustion engine during execution of a regeneration operation of the filter device (19a) for raising temperatures of exhaust gases is increased to collect trapped particulate matter from the exhaust gas Filter means (TR) for respectively turning on and off the glow plugs (20), a turn-on control means (31; 31A) for controlling turn-on operations of the switching elements, and determining means (S20) for determining whether a high-temperature anomaly state exists wherein the temperatures of the switching elements exceed a predetermined given temperature, wherein the glow plugs (20) are turned on during start of the internal combustion engine (10) and are also turned on to be the electric load during execution of the regeneration operation of the filtering device (19a) and the turn-on control means (31; 31A) includes a turn-on limiting means (S40, S61) for limiting turn-on duty ratio of the glow plugs when the determining means determines that the high-temperature anomaly condition exists.

Description

BACKGROUND OF THE INVENTION

TECHNICAL FIELD OF THE INVENTION

The present invention relates to glow plug control devices and glow control systems, and more particularly, to a glow plug control device and a glow control system for controlling a start-up of a glow plug provided in a diesel engine (diesel engine).

Description of the Related Art

The post-published DE 10 2008 054 490 A1 discloses a power supply control apparatus for glow plugs.

The US 2005/0 146 822 A1 discloses an ignition control apparatus for an internal combustion engine.

The post-published DE 10 2008 043 025 A1 discloses a method of operating an internal combustion engine.

The DE 10 2006 042 643 A1 discloses a method for tracking malfunctions in the operation of automobiles.

The post-published DE 10 2010 001 148 A1 discloses a diesel engine starting aid.

In the prior art, a DPF apparatus for receiving (trapping) particulates (particulate matter, particulate matter, PM) discharged from a diesel engine (diesel engine) has been known. With such a DPF device, a demand for performing a regenerative operation for burning PM occurs when the trapped PM exceeds a given level. In order to meet such a demand, there has been proposed a fuel injection control as shown in FIG JP 2006 - 152 891 A is disclosed. In such a fuel injection control, a main injection injection is initially performed, and a post injection is initiated at a subsequent time (time course) to force an increase in exhaust gas temperatures to allow compulsory burning of the trapped particulates. to remove them.

The inventor has made extensive studies of techniques for raising the temperatures of exhaust gases by, in addition to performing post-injection, an operation of performing a main injection with an increased fuel volume. In these detailed studies, it has been found that simply performing the main injection with an increased fuel volume causes an increase in the engine speed (hereinafter referred to as "NE") with a consequent increase in discomfort to the driver. In particular, during running of the vehicle at a low idling speed or the like, an increase in the rotational speed leads to an increase in discomfort to the driver.

SUMMARY OF THE INVENTION

The present invention has been made in consideration of the above-described point and has an object to provide a glow plug control apparatus and an annealing control system for minimizing an increase in engine speed during execution of a regenerative operation of a DPF apparatus.

Hereinafter, means and advantages for coping with the above-described point will be described.

According to a first aspect of the present invention, it is considered that a glow plug control device is applied to a glow plug installed in a combustion chamber of an internal combustion engine, the engine being composed of a filter device (DPF) for trapping particulates (particulate matter, particulate matter) in exhaust gases is constructed. According to the first aspect of the present invention, there is provided a regeneration activating means for controllably switching on an electric load to increase an electric load of a battery charged during the execution of a regenerative operation by the internal combustion engine so as to raise the temperatures of the exhaust gas such that trapped particulates are exhausted the filter device are removed. The glow plugs are turned on during startup of the engine and are also turned on to serve as an electrical load during the execution of the regenerative operation.

With such a structure, the electric load is controllably turned on during the execution of the regenerative operation so as to increase the electric load of the battery charged by the internal combustion engine acting as the drive source. This makes it possible to minimize the speed increase even when the regenerative operation is performed by performing a main injection with an increased fuel volume.

Further, according to the first aspect of the present invention, the glow plugs are turned on during starting of the internal combustion engine and also turned on to serve as the electric load during the execution of the regenerative operation. That is, the original purpose of the glow plugs is to preheat the combustors to aid in the initial ignitability of the engine during start-up thereof. Besides these purposes, the glow plugs are used as electrical loads for carrying out the regenerative operation of the filter device. In contrast to a concept of the present invention, if the headlamps of the vehicle were used as electrical loads, the regenerative operation would be performed with the consequence that, contrary to the intention of the driver, the headlights are turned on while the vehicle is running. On the other hand, according to the present invention, there is no danger of the driver feeling uncomfortable even if the regenerative operation is performed with the occurrence of the operation of the glow plugs during the running of the vehicle, because the glow plugs are used as the electric loads as described above. This enables the suppression of the speed increase during the execution of the regenerative operation taking into consideration the above-described point.

The turning on of the glow plugs results in a flow of a large electric current, which causes switching elements that switch the on states of the glow plugs to develop heat (see FIGS JP 2006 - 153 293 A ). Therefore, there is a fear that the heat tends to over-develop in the switching elements, so that they may be damaged. Further, if the glow plugs are turned on to serve as electrical loads during the execution of the regenerative operation of the DPF as described above, the execution of the regenerative operation of the DPF results in an extreme increase in the ambient temperatures around the glow plugs. The inventor has found through research that the attempt to carry out the first aspect of the present invention results in a likelihood of thermal damage occurring in the switching element.

According to such findings, according to the first aspect of the present invention, there are provided switching elements for respectively turning on and off the glow plugs, and a turn-on control means for controlling the turn-on operations of the switching elements and determining means for determining whether a high-temperature anomaly condition exists, at which temperatures Switching elements exceed a predetermined given temperature. The turn-on control means has a turn-on limiting means for limiting turn-on duty ratio rates of the glow plugs when the determining means determines that the high-temperature anomaly condition exists.

Such a structure can advantageously prevent the occurrence of thermal damage to the switching elements due to a turn-on effect of the glow plugs under a high-temperature environment.

At this time, when an inquiry is made as to whether a high-temperature anomaly condition exists, if an attempt is made to measure the electric currents flowing through the switching elements to determine that the measured electric current values exceed threshold values, a high-temperature anomaly exists is a point in a manner described below. That is, if ambient temperatures around the switching elements are at high levels, the temperatures of the switching elements (which will also be referred to as "element temperatures" hereinafter) will increase even if the measured currents have the same values. That is, it is difficult to predict accurate element temperatures by referring to the current values flowing through the switching elements. Therefore, with the determination made on the basis of such current values, there is a need to select the switching elements each having an allowable heat resistance performance such that no failure takes place even at a predicted maximum ambient temperature. Therefore, it is difficult to select switching elements that are low in cost and low in heat resistance performance. In an alternative, there is a need to prepare heat radiating means such as a heat sink or the like having high radiation capacities. In particular, an attempt to turn on the glow plugs as the electrical loads during the execution of the regenerative operation leads to the occurrence of current flowing through the switching elements, the ambient temperatures remaining at extremely high levels. Therefore, if an attempt is made to determine whether a high-temperature anomaly exists in the switching element by referring to a value of electric current flowing through the switching element, there is a need to select a switching element having a heat resistance performance extremely high thermal resistance.

In order to address such a point, according to a second aspect of the present invention, there is provided a temperature detecting means for detecting the temperature of the switching element, the determining means being responsive to the temperature detected by the temperature detecting means for determining whether the high temperature anomaly condition exists.

With such a structure, the temperature detecting means directly detects the temperatures (element temperatures) of the switching elements. This enables the element temperatures to be obtained more accurately than those obtained when the presence of the high temperature anomaly is determined based on the electric current values flowing through the switching elements. Therefore, there is no need to select the switching elements each having an increased heat resistance, thereby achieving a reduction in the heat resistance performance or the radiation capacity required for the heat radiating device such as the heat sink or the like.

According to a third aspect of the present invention, the regeneration activating means may preferably perform on-control of a plurality of electric loads including the glow plugs during execution of the regenerative operation, the regeneration activating means preferably having duty ratios (duty ratio rates) of electrical loads other than the glow plugs in the presence of a high-temperature anomaly condition Increases levels that are greater than those of the electrical loads for normal operation.

With such a construction, the plurality of electrical loads increase the capacity of the electrical loads, resulting in a capability of adequately achieving further suppression of the speed increase than that achieved when the electric load is increased using a single electrical load.

Further, concrete examples of performing the power-on control in the presence of the plurality of other electrical loads may preferably increase a duty ratio of the plurality of other electrical loads simultaneously in the presence of the high-temperature anomaly condition (according to a fourth aspect of the present invention) and alternately increase power-up ratio rates of the plurality of power-ups have other electrical loads to increase the duty cycle of any of the plurality of other electrical loads in the presence of the high temperature anomaly condition (according to a fifth aspect of the present invention).

In such examples, turning on the other electrical loads enables the increase in the electrical load to be compensated preferably during the regenerative operation, even if the on states of the glow plugs are limited due to the high temperature anomaly.

Here, concrete examples of the other electric loads may preferably be an electric heater (intake air heater) for superheating intake air drawn into the combustion chambers, electric heater (seat heater) for heating a passenger or driver's seat of the vehicle, electric heater (windshield heater) which is attached to a rear windshield, and an electric fan of a fan heater and so on. The operation of these electrical loads during the regenerative operation results in the result that, for example, the headlights are turned on contrary to the intention of the driver, causing an uncomfortable feeling in the driver.

To cope with such a point, according to a sixth aspect of the present invention, the regeneration activating means is enabled to interrupt the other electrical loads from turning on for the normal operation even when the high temperature anomaly condition exists. This makes it possible to reduce the opportunities of operating the other electrical loads during regenerative operation, thereby minimizing the opportunities that could cause the driver to feel uncomfortable, as described above. In addition, even when the glow plugs are operated as the electric loads, no uncomfortable feeling is caused to the driver.

According to a seventh aspect of the present invention, preferably, the regeneration activating means may extend a time during which the electric load is turned on in the presence of the high-temperature anomaly state to a value larger than that of the normal-load electrical load.

With such a structure, even if the on states of the glow plugs are limited due to the high-temperature anomaly, the time interval in which the electric loads are turned on is extended, which preferably compensates for an increase in the electrical loads during the regenerative operation.

According to an eighth aspect of the present invention, preferably, the regeneration activating means may retard the execution of the regenerative operation when the high-temperature anomaly condition exists.

Such a structure prevents the electrical loads during the regenerative operation from rising under a state in which the on states of the glow plugs are controlled.

Concrete examples of the limitation of the on states of the glow plugs may preferably include turning off the switching element or decreasing the turn-on duty ratio of the on-state (according to a ninth aspect of the present invention).

This easily realizes an effect that the on-load ratios are brought to zero or reduced.

According to a tenth aspect of the present invention, preferably, the power-on control means controls the operation of the switching device based on a command signal outputted from a command control device, and if the power-on limiting device executes the power-on restriction as opposed to a command content of the command signal, the power-on control means applies a DIAG signal to the power-on device Issue command control device to communicate the execution of the power-on limit.

With such a structure, when the electrical loads are turned on during the regenerative operation, it becomes possible to control the on states of the electrical loads that match a DIAG signal (diagnostic signal).

According to an eleventh aspect of the present invention, the engine may preferably include a plurality of cylinders formed with combustion chambers in which the glow plugs are mounted, and the turn-on control device outputs the DIAG signal for each of the glow plugs.

With such a structure, the electrical loads can be controllably and sensitively turned on in a manner that matches the DIAG signal. That is, the electric power consumed with the other electrical loads may be regulated depending on the number of glow plugs which remain inoperative due to the occurrence of the high-temperature anomaly. According to an alternative, the on-load ratios of the glow plugs which do not stop the operation due to the high-temperature anomaly are increased in regions not causing errors in the glow plugs, thereby making it possible to control the power consumption to be consumed by the glow plugs.

In general, when the glow plug is turned on for the purpose of assisting initial ignitability, a duty cycle of a turn-on signal is rapidly increased stepwise (see FIG. 19 (b) ). When this occurs, an inrush current flows through the glow plug, and therefore the electric power consumption of the glow plug increases for a few seconds (see FIG. 19 (a) ). However, when the glow plug is turned on during the execution of the regenerative operation as described above, if the electric power consumption increases due to the inrush current, a fluctuation in the magnitude of the electric load occurs. This is reflected in a fluctuation in the rotational speed when an effort is made to suppress the speed increase during the execution of the regenerative operation.

In view of the above, according to a twelfth aspect of the present invention, at the start of turning on the glow plugs with the execution of the regenerative operation, duty ratios for turning on the switching elements are gradually increased (see FIG. 19 (d) ). This prevents the electric power consumption of the glow plug from rising for a few seconds due to the inrush current (see FIG. 19 (c) ). Therefore, it becomes possible to prevent a fluctuation in the magnitude of the electric load that occurs when the glow plug is turned on during the execution of the regenerative operation.

A thirteenth aspect of the present invention is characterized in that the glow plugs (at start glow) are turned on so as to assist the initial ignitability of the engine during starting thereof, and also to be turned on (during afterglow) to cause burns in the engine itself during a period of time after starting (aft-startup period) to stabilize.

In doing so, when attempting to perform a prior art control with the element temperature assumed with reference to the current value flowing through the switching element, a need arises that a current threshold value based on which the high temperature anomaly is to be determined. takes a high value as described above. However, the attempt to perform the afterglow in the prior art control results in a fear that an electric current that is slightly lower than the current threshold will be continuous for one long time (time after starting) flows. In such a case, there is a risk that deterioration or the like will occur in the switching element, although it is not determined that there is a high temperature abnormality.

According to the thirteenth aspect of the present invention, the element temperature is directly detected, and therefore the presence of a high-temperature anomaly can be accurately detected even in such an afterglow, thereby enabling the turn-on duty ratio of the glow plug to be suitably limited.

In this connection, examples of a case in which afterglow is performed may include a phase applied to a low-compression-ratio engine and another phase in which the engine is operated at high altitude with thin air. This is due to the fact that even if the engine starts during start-up glow, these phases have a risk that a misfire will occur in the absence of subsequent afterglow.

In order to deal with the point that occurs when the high-temperature anomaly is detected in the afterglow, it is more preferable that the duty ratio of the turn-on signal is selected to be smaller than that of the turn-off signal applied to the switching element. This is because interrupting the off state results in the occurrence of a misfire. Further, when the high-temperature anomaly is present, the fuel injection timing (fuel injection timing) may be changed to achieve stabilized combustion. In addition, the on-duty ratio of the glow plug for afterglow may preferably be selected to be smaller than that of the glow plug for start glow to achieve stabilized combustion while preventing occurrence of the high-temperature anomaly.

According to a fourteenth aspect of the present invention, there is provided a glow plug control system including the glow plugs and / or the filter device and / or the glow plug control device.

With such a glow plug control system, the same advantageous effects as those mentioned above can be achieved.

list of figures

• 1 eine schematische Darstellung zur Veranschaulichung eines Maschinensystems, bei dem eine Glühkerzensteuerungsvorrichtung gemäß einem ersten Ausführungsbeispiel der vorliegenden Erfindung angewandt ist.
• 2 zeigt ein Blockschaltbild zur Veranschaulichung einer Funktion einer in 1 gezeigten GDU.
• 3 zeigt eine Querschnittsdarstellung zur Veranschaulichung eines Hardware-Aufbaus der in 1 gezeigten GDU.
• 4 zeigt ein Flussdiagramm, das einen Grundablauf einer Hochtemperaturanomalie-Bestimmungsroutine zeigt, die durch die Glühkerzensteuerungsvorrichtung gemäß dem ersten Ausführungsbeispiel gemäß 1 ausgeführt wird.
• 5 zeigt ein Flussdiagramm, das einen Grundablauf einer Hochtemperaturanomalie-Bestimmungsroutine gemäß einem zweiten Ausführungsbeispiel gemäß der vorliegenden Erfindung darstellt.
• 6(a) zeigt einen Signalverlauf, der ein in der Glühkerzensteuerungsvorrichtung gemäß dem zweiten Ausführungsbeispiel verwendetes Befehlssignal darstellt.
• 6(b) zeigt einen Signalverlauf, der ein tatsächliches Einschaltsignal veranschaulicht, das beim Einschalten eines Schaltelements der Glühkerzensteuerungsvorrichtung gemäß dem zweiten Ausführungsbeispiel verwendet wird.
• 7 zeigt ein Blockschaltbild, das eine Vielzahl von elektrischen Lasten darstellt, bei denen einen Glühkerzensteuerungsvorrichtung gemäß einem dritten Ausführungsbeispiel der vorliegenden Erfindung angewandt wird.
• 8(a) zeigt einen Signalverlauf, der ein in der Glühkerzensteuerungsvorrichtung gemäß dem dritten Ausführungsbeispiel verwendetes Befehlssignal darstellt.
• 8(b) zeigt einen Signalverlauf, der ein in der Glühkerzensteuerungsvorrichtung gemäß dem dritten Ausführungsbeispiel verwendetes DIAG-Signal darstellt.
• 9(a) zeigt einen Signalverlauf, der ein aus einer ECU ausgegebenes erstes Befehlssignal zur Steuerung einer ersten elektrischen Last (Glühkerze) in der Glühkerzensteuerungsvorrichtung gemäß dem dritten Ausführungsbeispiel darstellt.
• 9(b) zeigt einen Signalverlauf, der ein erstes Einschaltsignal darstellt, das aus einer ersten Steuerungs-IC zum Einschalten eines ersten Schaltelements zugeführt wird, das in der Glühkerzensteuerungsvorrichtung gemäß dem dritten Ausführungsbeispiel verwendet wird.
• 9(c) zeigt einen Signalverlauf, der ein aus einem ersten Steuerungs-IC zu einer in der Glühkerzensteuerungsvorrichtung gemäß dem dritten Ausführungsbeispiel eingebauten ECU ausgegebenes DIAG-Signal darstellt.
• 9(d) zeigt einen Signalverlauf, der ein aus der ECU ausgegebenes zweites Befehlssignal zur Steuerung einer zweiten elektrischen Last in der Glühkerzensteuerungsvorrichtung gemäß dem dritten Ausführungsbeispiel darstellt.
• 9(e) einen Signalverlauf, der ein zweites Einschaltsignal darstellt, das aus einer zweiten Steuerungs-IC zum Einschalten eines zweiten Schaltelements zugeführt wird, das in der Glühkerzensteuerungsvorrichtung gemäß dem dritten Ausführungsbeispiel verwendet wird.
• 9(f) zeigt einen Signalverlauf, der ein aus der ECU ausgegebenes drittes Befehlssignal darstellt, um eine dritte elektrische Last in der Glühkerzensteuerungsvorrichtung gemäß dem dritten Ausführungsbeispiel zu steuern.
• 9(g) zeigt einen Signalverlauf, der ein aus einem dritten Steuerungs-IC zugeführtes drittes Einschaltsignal zum Einschalten eines dritten Schaltelements zugeführt wird, das in der Glühkerzensteuerungsvorrichtung gemäß dem dritten Ausführungsbeispiel verwendet wird.
• 10 zeigt ein Flussdiagramm, das einen Grundablauf der Steuerung von Einschaltzuständen verschiedener elektrischer Lasten darstellt, bei denen das dritte Ausführungsbeispiel der vorliegenden Erfindung angewandt wird.
• 11(a) zeigt einen Signalverlauf, der ein aus einer ECU ausgegebenes erstes Befehlssignal zur Steuerung einer ersten elektrischen Last (Glühkerze) in einer Glühkerzensteuerungsvorrichtung gemäß einem vierten Ausführungsbeispiel der vorliegenden Erfindung darstellt.
• 11(b) zeigt einen Signalverlauf, der ein erstes aus einem ersten Steuerungs-IC zugeführtes Einschaltsignal darstellt, das in der Glühkerzensteuerungsvorrichtung gemäß dem vierten Ausführungsbeispiel verwendet wird.
• 11(c) zeigt einen Signalverlauf, der ein DIAG-Signal darstellt, das aus einem ersten Steuerungs-IC zu einer in der Glühkerzensteuerungsvorrichtung gemäß dem vierten Ausführungsbeispiel enthaltenen ECU ausgegeben wird.
• 11(d) zeigt einen Signalverlauf, der ein aus der ECU ausgegebenes zweites Befehlssignal zur Steuerung einer zweiten elektrischen Last in der Glühkerzensteuerungsvorrichtung gemäß dem vierten Ausführungsbeispiel darstellt.
• 11(e) zeigt einen Signalverlauf, der ein zweites Einschaltsignal darstellt, das aus einem zweiten Steuerungs-IC zum Einschalten eines zweiten Schaltelements zugeführt wird, das in der Glühkerzensteuerungsvorrichtung gemäß dem vierten Ausführungsbeispiel verwendet wird.
• 11(f) zeigt einen Signalverlauf, der ein aus der ECU ausgegebenes drittes Befehlssignal zur Steuerung einer dritten elektrischen Last in der Glühkerzensteuerungsvorrichtung gemäß dem vierten Ausführungsbeispiel darstellt.
• 11(g) zeigt einen Signalverlauf, der ein aus einem dritten Steuerungs-IC zugeführtes drittes Einschaltsignal zum Einschalten eines dritten Schaltelements darstellt, das bei der Glühkerzensteuerungsvorrichtung gemäß dem vierten Ausführungsbeispiel verwendet wird.
• 12 zeigt ein Flussdiagramm, das einen Grundablauf der Steuerung von Einschaltzuständen verschiedener elektrischer Lasten veranschaulicht, bei denen das vierte Ausführungsbeispiel der vorliegenden Erfindung angewandt wird.
• 13(a) zeigt einen Signalverlauf, der ein aus der ECU ausgegebenes erstes Befehlssignal zur Steuerung einer ersten elektrischen Last (Glühkerze) in einer Glühkerzensteuerungsvorrichtung gemäß einem fünften Ausführungsbeispiel der vorliegenden Erfindung darstellt.
• 13(b) zeigt einen Signalverlauf, der ein erstes Einschaltsignal darstellt, das aus einem ersten Steuerungs-IC zugeführt wird, um ein erstes Schaltelement einzuschalten, das in der Glühkerzensteuerungsvorrichtung gemäß dem fünften Ausführungsbeispiel verwendet wird.
• 13(c) zeigt einen Signalverlauf, der ein DIAG-Signal darstellt, das aus einem ersten Steuerungs-IC zu einer in der Glühkerzensteuerungsvorrichtung gemäß dem fünften Ausführungsbeispiel enthaltenen ECU ausgegeben wird.
• 13(d) zeigt einen Signalverlauf, der ein aus der ECU ausgegebenes zweites Befehlssignal zur Steuerung einer zweiten elektrischen Last in der Glühkerzensteuerungsvorrichtung gemäß dem fünften Ausführungsbeispiel darstellt.
• 13(e) zeigt einen Signalverlauf, der ein aus einem zweiten Steuerungs-IC zugeführtes zweites Einschaltsignal zum Einschalten eines zweiten Schaltelements darstellt, das in der Glühkerzensteuerungsvorrichtung gemäß dem fünften Ausführungsbeispiel verwendet wird.
• 13(f) zeigt einen Signalverlauf, der ein aus der ECU ausgegebenes drittes Befehlssignal zur Steuerung einer dritten elektrischen Last in der Glühkerzensteuerungsvorrichtung gemäß dem fünften Ausführungsbeispiel darstellt.
• 13(g) zeigt einen Signalverlauf, der ein aus einem dritten Steuerungs-IC zugeführtes drittes Einschaltsignal zum Einschalten eines dritten Schaltelements darstellt, das bei der Glühkerzensteuerungsvorrichtung gemäß dem fünften Ausführungsbeispiel verwendet wird.
• 14 zeigt ein Flussdiagramm, das einen Grundablauf der Steuerung von Einschaltzuständen verschiedener elektrischer Lasten darstellt, bei denen das fünfte Ausführungsbeispiel gemäß der vorliegenden Erfindung angewandt wird.
• 15(a) zeigt einen Signalverlauf, der ein aus der ECU ausgegebenes erstes Befehlssignal zur Steuerung einer ersten elektrischen Last (Glühkerze) bei einer Glühkerzensteuerungsvorrichtung gemäß einem sechsten Ausführungsbeispiel der vorliegenden Erfindung darstellt.
• 15(b) zeigt einen Signalverlauf, der ein aus einem ersten Steuerungs-IC zugeführtes erstes Einschaltsignal zum Einschalten eines ersten Schaltelements darstellt, das bei der Glühkerzensteuerungsvorrichtung gemäß dem sechsten Ausführungsbeispiel verwendet wird.
• 15(c) zeigt einen Signalverlauf, der ein DIAG-Signal darstellt, das aus einem ersten Steuerungs-IC zu einer in der Glühkerzensteuerungsvorrichtung gemäß dem sechsten Ausführungsbeispiel eingebauten ECU ausgegeben wird.
• 15(d) zeigt einen Signalverlauf, der ein zweites Befehlssignal darstellt, das aus der ECU zur Steuerung einer zweiten elektrischen Last in der Glühkerzensteuerungsvorrichtung gemäß dem sechsten Ausführungsbeispiel ausgegeben wird.
• 15(e) zeigt einen Signalverlauf, der ein aus einem zweiten Steuerungs-IC zugeführtes zweites Einschaltsignal zum Einschalten eines zweiten Schaltelements darstellt, das in der Glühkerzensteuerungsvorrichtung gemäß dem sechsten Ausführungsbeispiel verwendet wird.
• 15(f) zeigt einen Signalverlauf, der ein aus der ECU ausgegebenes drittes Befehlssignal zur Steuerung einer dritten elektrischen Last in der Glühkerzensteuerungsvorrichtung gemäß dem sechsten Ausführungsbeispiel darstellt.
• 15(g) zeigt einen Signalverlauf, der ein aus einem dritten Steuerungs-IC zugeführtes drittes Einschaltsignal zum Einschalten eines dritten Schaltelements darstellt, das in der Glühkerzensteuerungsvorrichtung gemäß dem sechsten Ausführungsbeispiel verwendet wird.
• 16 zeigt ein Flussdiagramm, das einen Grundablauf der Steuerung von Einschaltzuständen verschiedener elektrischen Lasten darstellt, bei denen das sechste Ausführungsbeispiel gemäß der vorliegenden Erfindung angewendet wird.
• 17(a) zeigt einen Signalverlauf, der ein aus der ECU ausgegebenes erstes Befehlssignal zur Steuerung einer ersten elektrischen Last (Glühkerze) in einer Glühkerzensteuerungsvorrichtung gemäß einem siebten Ausführungsbeispiel der vorliegenden Erfindung darstellt.
• 17(b) zeigt einen Signalverlauf, der ein aus einem ersten Steuerungs-IC zugeführtes erstes Einschaltsignal zum Einschalten eines ersten Schaltelements darstellt, das in der Glühkerzensteuerungsvorrichtung gemäß dem siebten Ausführungsbeispiel verwendet wird.
• 17(c) zeigt einen Signalverlauf, der ein DIAG-Signal darstellt, das aus einem ersten Steuerungs-IC zu einer in der Glühkerzensteuerungsvorrichtung gemäß dem siebten Ausführungsbeispiel eingebauten ECU ausgegeben wird.
• 17(d) zeigt einen Signalverlauf, der ein aus der ECU ausgegebenes zweites Befehlssignal zur Steuerung einer zweiten elektrischen Last in der Glühkerzensteuerungsvorrichtung gemäß dem siebten Ausführungsbeispiel darstellt.
• 17(e) zeigt einen Signalverlauf, der ein aus einem zweiten Steuerungs-IC zugeführtes zweites Einschaltsignal zum Einschalten eines zweiten Schaltelements darstellt, das in der Glühkerzensteuerungsvorrichtung gemäß dem siebten Ausführungsbeispiel verwendet wird.
• 17(f) zeigt einen Signalverlauf, der ein aus der ECU ausgegebenes drittes Befehlssignal zur Steuerung einer dritten elektrischen Last in der Glühkerzensteuerungsvorrichtung gemäß dem siebten Ausführungsbeispiel darstellt.
• 17(g) zeigt einen Signalverlauf, der ein aus einem dritten Steuerungs-IC zugeführtes drittes Einschaltsignal zum Einschalten eines dritten Schaltelements darstellt, das in der Glühkerzensteuerungsvorrichtung gemäß dem siebten Ausführungsbeispiel verwendet wird.
• 18 zeigt ein Flussdiagramm, das einen Grundablauf zur Steuerung von Einschaltzuständen verschiedener elektrischen Lasten darstellt, auf das das siebte Ausführungsbeispiel gemäß der vorliegenden Erfindung angewandt wird.
• 19(a) bis 19(d) zeigen Zeitverläufe, die eine mit einer Glühsteuerungsvorrichtung gemäß einem achten Ausführungsbeispiel der vorliegenden Erfindung auszuführende Steuerungsroutine darstellen.
• 20 zeigt ein Blockschaltbild zur Veranschaulichung einer Funktion einer GDU, die Teil einer Glühsteuerungsvorrichtung gemäß einem neunten Ausführungsbeispiel der vorliegenden Erfindung bildet.

These and other features and advantages of the present invention will become apparent from the following description with reference to the accompanying drawings. Show it:

• 1 a schematic representation of a machine system to which a glow plug control device according to a first embodiment of the present invention is applied.
• 2 shows a block diagram illustrating a function of an in 1 GDU shown.
• 3 FIG. 12 is a cross-sectional view illustrating a hardware construction of FIG 1 GDU shown.
• 4 FIG. 14 is a flowchart showing a basic procedure of a high-temperature abnormality determination routine executed by the glow plug control apparatus according to the first embodiment of FIG 1 is performed.
• 5 FIG. 12 is a flowchart illustrating a basic flow of a high temperature abnormality determination routine according to a second embodiment of the present invention. FIG.
• 6 (a) FIG. 12 is a waveform showing a command signal used in the glow plug control apparatus according to the second embodiment. FIG.
• 6 (b) FIG. 15 is a waveform illustrating an actual turn-on signal used when turning on a switching element of the glow plug control device according to the second embodiment. FIG.
• 7 FIG. 15 is a block diagram illustrating a plurality of electrical loads to which a glow plug control device according to a third embodiment of the present invention is applied.
• 8 (a) shows a waveform, a in the Glow plug control device according to the third embodiment used command signal.
• 8 (b) FIG. 15 is a waveform showing a DIAG signal used in the glow plug control apparatus according to the third embodiment. FIG.
• 9 (a) FIG. 15 is a waveform showing a first command signal output from an ECU for controlling a first electric load (glow plug) in the glow plug control device according to the third embodiment.
• 9 (b) FIG. 15 shows a waveform representing a first turn-on signal supplied from a first control IC for turning on a first switching element used in the glow plug control device according to the third embodiment.
• 9 (c) FIG. 12 is a waveform showing a DIAG signal output from a first control IC to an ECU installed in the glow plug control device according to the third embodiment.
• 9 (d) FIG. 15 is a waveform showing a second command signal output from the ECU for controlling a second electric load in the glow plug control device according to the third embodiment. FIG.
• 9 (e) FIG. 14 is a waveform showing a second turn-on signal supplied from a second control IC for turning on a second switching element used in the glow plug control device according to the third embodiment.
• 9 (f) FIG. 15 is a waveform showing a third command signal output from the ECU to control a third electric load in the glow plug control device according to the third embodiment. FIG.
• 9 (g) FIG. 15 shows a waveform to which a third turn-on signal supplied from a third control IC is supplied to turn on a third switching element used in the glow plug control device according to the third embodiment.
• 10 FIG. 12 is a flowchart illustrating a basic flow of control of on states of various electrical loads to which the third embodiment of the present invention is applied.
• 11 (a) FIG. 12 is a waveform showing a first command signal output from an ECU for controlling a first electric load (glow plug) in a glow plug control device according to a fourth embodiment of the present invention. FIG.
• 11 (b) FIG. 12 is a waveform showing a first ON signal supplied from a first control IC used in the glow plug control apparatus according to the fourth embodiment. FIG.
• 11 (c) FIG. 15 is a waveform showing a DIAG signal output from a first control IC to an ECU included in the glow plug control device according to the fourth embodiment. FIG.
• 11 (d) FIG. 12 is a waveform showing a second command signal output from the ECU for controlling a second electric load in the glow plug control device according to the fourth embodiment. FIG.
• 11 (e) FIG. 12 is a waveform showing a second turn-on signal supplied from a second control IC for turning on a second switching element used in the glow plug control device according to the fourth embodiment.
• 11 (f) FIG. 12 is a waveform showing a third command signal output from the ECU for controlling a third electric load in the glow plug control device according to the fourth embodiment. FIG.
• 11 (g) FIG. 15 is a waveform showing a third turn-on signal supplied from a third control IC for turning on a third switching element used in the glow plug control device according to the fourth embodiment.
• 12 FIG. 12 is a flow chart illustrating a basic flow of control of ON states of various electrical loads to which the fourth embodiment of the present invention is applied. FIG.
• 13 (a) FIG. 12 is a waveform showing a first command signal output from the ECU for controlling a first electric load (glow plug) in a glow plug control device according to a fifth embodiment of the present invention.
• 13 (b) FIG. 15 shows a waveform representing a first turn-on signal supplied from a first control IC to turn on a first switching element used in the glow plug control device according to the fifth embodiment.
• 13 (c) FIG. 15 is a waveform showing a DIAG signal output from a first control IC to an ECU included in the glow plug control device according to the fifth embodiment. FIG.
• 13 (d) FIG. 15 is a waveform showing a second command signal output from the ECU for controlling a second electric load in the glow plug control device according to the fifth embodiment. FIG.
• 13 (e) FIG. 15 is a waveform showing a second ON signal supplied from a second control IC for turning on a second switching element used in the glow plug control device according to the fifth embodiment. FIG.
• 13 (f) FIG. 15 is a waveform showing a third command signal output from the ECU for controlling a third electric load in the glow plug control device according to the fifth embodiment. FIG.
• 13 (g) FIG. 15 is a waveform showing a third turn-on signal supplied from a third control IC for turning on a third switching element used in the glow plug control device according to the fifth embodiment.
• 14 FIG. 12 is a flow chart showing a basic flow of control of on states of various electrical loads to which the fifth embodiment according to the present invention is applied.
• 15 (a) FIG. 12 is a waveform showing a first command signal output from the ECU for controlling a first electric load (glow plug) in a glow plug control device according to a sixth embodiment of the present invention. FIG.
• 15 (b) FIG. 12 is a waveform showing a first turn-on signal supplied from a first control IC for turning on a first switching element used in the glow plug control device according to the sixth embodiment.
• 15 (c) FIG. 15 is a waveform showing a DIAG signal output from a first control IC to an ECU incorporated in the glow plug control device according to the sixth embodiment. FIG.
• 15 (d) FIG. 15 is a waveform showing a second command signal outputted from the ECU for controlling a second electric load in the glow plug control device according to the sixth embodiment. FIG.
• 15 (e) FIG. 12 is a waveform showing a second ON signal supplied from a second control IC for turning on a second switching element used in the glow plug control device according to the sixth embodiment. FIG.
• 15 (f) FIG. 15 is a waveform showing a third command signal outputted from the ECU for controlling a third electric load in the glow plug control device according to the sixth embodiment. FIG.
• 15 (g) FIG. 12 is a waveform showing a third turn-on signal supplied from a third control IC for turning on a third switching element used in the glow plug control device according to the sixth embodiment.
• 16 FIG. 12 is a flow chart showing a basic flow of control of ON states of various electrical loads to which the sixth embodiment according to the present invention is applied.
• 17 (a) FIG. 12 is a waveform showing a first command signal output from the ECU for controlling a first electric load (glow plug) in a glow plug control device according to a seventh embodiment of the present invention.
• 17 (b) FIG. 15 is a waveform showing a first turn-on signal supplied from a first control IC for turning on a first switch element used in the glow plug control device according to the seventh embodiment.
• 17 (c) FIG. 15 is a waveform showing a DIAG signal output from a first control IC to an ECU incorporated in the glow plug control device according to the seventh embodiment. FIG.
• 17 (d) FIG. 15 is a waveform showing a second command signal output from the ECU for controlling a second electric load in the glow plug control device according to the seventh embodiment. FIG.
• 17 (e) FIG. 12 is a waveform showing a second ON signal supplied from a second control IC for turning on a second switching element used in the glow plug control device according to the seventh embodiment. FIG.
• 17 (f) FIG. 15 is a waveform showing a third command signal outputted from the ECU for controlling a third electric load in the glow plug control device according to the seventh embodiment. FIG.
• 17 (g) FIG. 12 is a waveform showing a third turn-on signal supplied from a third control IC for turning on a third switching element used in the glow plug control device according to the seventh embodiment.
• 18 FIG. 12 is a flow chart showing a basic procedure for controlling on states of various electric loads to which the seventh embodiment according to the present invention is applied.
• 19 (a) to 19 (d) FIG. 10 is a time chart showing a control routine to be executed with a glow control apparatus according to an eighth embodiment of the present invention. FIG.
• 20 FIG. 12 is a block diagram illustrating a function of a GDU forming part of a glow control apparatus according to a ninth embodiment of the present invention. FIG.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Hereinafter, glow control devices and glow control systems according to various embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the present invention should not be limited to the embodiments described below, but technical concepts according to the present invention may be implemented in combination with other known techniques or other technique having functions equivalent to such known techniques.

embodiments

Hereinafter, the glow control devices according to various concrete embodiments implementing the present invention will be described in detail with reference to the accompanying drawings. In the following description, like reference characters designate like corresponding component parts throughout the several views.

First embodiment

A glow plug control device according to a first embodiment of the present invention will be described below with reference to FIG 1 to 4 described. The present invention is implemented in a concrete form of an engine system (internal combustion engine system) mainly comprising a vehicle-mounted diesel engine (diesel engine), a detailed structure of which is described below. First, an overall structure of such a machine system according to the present embodiment is explained with reference to FIG 1 described.

As it is in 1 is shown has a diesel engine 10 an air inlet duct 11 on that via an inlet valve (intake valve) 12 with a combustion chamber 15 connected in a cylinder block 13 is shaped and with a piston 14 is delimited or defined. The combustion chamber 15 has an upper end portion to which a leading end 16a a fuel injection valve 16 protrudes (sticks out) to fuel into the combustion chamber 15 inject. After the fuel injection valve 16 Fuel into the combustion chamber 15 injects, the piston moves 14 upwards to fuel in the combustion chamber 15 to compress, whereupon autoignition occurs in the fuel to generate mechanical energy. This mechanical energy is called the rotational energy of an output shaft (crankshaft) 17 the diesel engine 10 extracted. In this case, gases resulting from the combustion of fuel, through an exhaust passage 19 (Exhaust port) discharged when an exhaust valve 18 is opened. A DPF device (diesel particulate filter device) 19a is on the exhaust duct 19 for collecting particles (particulate matter, PM ) in the through the exhaust duct 19 installed exhaust gases.

Furthermore, the cylinder block carries 13 a glow plug on it 20 that is a leading end 20a that is in the combustion chamber 15 projects. A glow plug drive unit (hereinafter referred to as "GDU") 30 is with a battery 21 connected to a turn-on state of the glow plug 20 produce or interrupt. During a cold start of the diesel engine 10 gets the glow plug 20 electric power for preheating the combustion chamber 15 fed. This allows that into the combustion chamber 15 drawn air fuel mixture has an improved initial ignitability. In addition, according to the present embodiment, the diesel engine 10 a variety of cylinders on which the glow plugs 20 each attached.

A crank angle sensor 24 is on the cylinder block 13 in an area in close proximity to the crankshaft 17 attached to a rotation angle (rotation angle) of the crankshaft 17 capture. A water temperature sensor 25 is also on the cylinder block 13 attached to a cooling water jacket WJ to detect the temperature of cooling water in the cooling water jacket WJ of the diesel engine. The fuel injector 16 , the crank angle sensor 24 , the water temperature sensor 25 and the GDU 30 are with an ECU (serving as regeneration activating means) 40 connected.

The ECU 40 has an electronic control unit consisting mainly of a known microcomputer is equipped, which is equipped with a CPU, memory and input / output interface, etc. The memories store a variety of programs and parameters to allow the CPU to execute the programs stored in the memories, thereby removing various parts of the diesel engine 10 to be controlled. The control of the operation of the fuel injection valves 16 controls the ECU 40 Fuel injection modes such as fuel injection amounts, fuel injection timings (fuel injection timings) and the number of stages for multi-stage injections to be executed at multiple injections for each combustion cycle. Furthermore, the ECU controls 40 the operation of the glow plug 20 in a manner which is described in detail later in the description.

The following is a structure of the GDU 30 with reference to 2 described. In 2 a solid line indicates the GDU 30 , and indicate single-component lines (dashed, broken lines) other component parts. The GDU 30 has a control IC 31 (Power-on control device) and a power element TR (Switching element). Concrete examples of the performance element TR For example, a power transistor such as a power MOSFET and an insulated gate bipolar transistor IGBT may be included. The ECU (command control unit) 40 gives a command signal CS1 from the control IC 31 is supplied. This command signal 1 is a duty signal for performing duty control of the glow plug 20 , The control IC 31 reinforces that from the ECU 40 supplied command signal for generating a switch-on signal. The performance element TR opens or closes an electrical power supply path between the battery 21 and the glow plug 20 in response to that from the control IC 31 supplied turn-on signal, whereby a turn-on state of the glow plug 20 is controlled.

Although according to the present embodiment, the glow plugs 20 each attached to the cylinder and the GDU 30 the power elements TR, each for the glow plugs 20 attached as described above is merely a single glow plug 20 and a single power element TR in 2 shown, with other glow plugs 20 and the other power elements TR have been omitted for ease of illustration.

Below is a hardware structure of the GDU 30 with reference to 3 described. The performance elements TR and the control IC 31 are on a metal plate 33 attached to a surface thereof and are electrically connected to each other by wire-bonding. Under the connections T1 to T5 is the connection T2 electrically with the metal plate 33 connected by wire bonding. In addition, the connection T3 electrically connected to the power element TR by wire bonding. Furthermore, the battery 21 with the connection T2 connected and is the glow plug 20 with the connection T3 connected. Accordingly, out of the battery 21 supplied electric power the glow plugs 20 over the metal plate 33 , the performance element TR and the connection T3 respectively supplied. In addition, the connection is used T5 for supplying electric power from the battery 24 to the control IC 31 ,

Furthermore, the metal plate is used 33 also serving as a heat radiating plate for radiating heat contained in the power elements TR and the control IC 31 is developed. On the other surface of the metal plate 33 For example, a heat sink (heat radiating device) (not shown) may be attached.

The connections T1 and T4 are electrically connected to the control IC by wire bonding. The from the ECU 40 supplied command signals are via the terminals T1 in the control IC 31 which generates a DIAG (diagnostic) signal that the ECU 40 over the connection T4 is supplied.

Furthermore, the thermosensors (temperature sensing elements) 32 on chips of the power elements TR for detecting temperatures of the power elements TR appropriate. Specific examples of the thermal sensors 32 may include thermal diodes and thermistors, etc. The thermosensors 32 are electrical with the control IC 31 connected by wire bonding.

The performance elements TR , the control IC 31 , the metal plate 33 , the thermal sensors 32 and parts of the connections T1 to T7 are bonded together by a resin shield. At the in 3 The structure shown is the resin shield 34 Shown in a cross section and indicated by a hatched area. The resin shield 34 prevents various wire bonded component parts from shorting due to adhesion of moisture and foreign materials.

With such a construction as described above, the ECU outputs 40 during a cold start of the diesel engine 10 the command signal to the glow plug 20 to turn it off. Below is the switch-on phase of the glow plug 20 to support the initial ignitability during a cold start referred to as "cold start assist turning on". Continue another switch-on phase of the glow plug 20 performed in the DPF regeneration, hereinafter referred to as "DPF regeneration turn-on". In addition, it is assumed that the DPF regeneration turn-on is performed for a given time interval of, for example, approximately 30 minutes.

The DPF device 19a must be subjected to a PM combustion regeneration operation when the trapped particulates (PM) exceed a given level. When injecting fuel into the diesel engine 10 a main injection is carried out, and subsequently a post injection is performed to the diesel engine 10 to allow exhaust gases, the temperature of which has been forcedly raised to a value of, for example, 500 ° C to 605 ° C, to be forced to forcibly burn the trapped particulate matter (PM) for removal. In addition, the term "main injection and post-injection" refers to fuel injections for injecting fuel into the diesel engine multiple times 10 for each combustion cycle, the main injection being fuel for rotatably driving the output shaft 17 to inject, and the post-injection is carried out after the main injection to contribute to an increase of the exhaust gases.

With the regenerative operation performed according to the present embodiment, besides performing such a post injection, the main injection is performed with an increased fuel volume, thereby increasing the temperature of the exhaust gases. However, attempting only to increase the volume of the fuel in the main injection leads to an increase in the engine speed (NE), which causes a driver to experience an uncomfortable feeling. In particular, during a low-speed operation mode such as an idle-drive mode, the speed increase leads to a marked increase in the unpleasant feeling.

In the glow plug control apparatus according to the present embodiment, particular attention is paid to an effect in which the battery 21 is charged by the electric power that is generated when a drive source in the form of the output shaft 17 is used, and further attention is paid to an effect in which the increase of an electric load of the battery 21 allows the main injection to be performed with increased fuel volume without causing the speed increase. That is, during the regenerative operation in which the main injection is performed with an increased fuel volume, the drive of the glow plug 20 causes the electrical load of the battery 21 elevated. This allows the main injection to be performed with the increased fuel volume while minimizing the speed increase. During the execution of such regenerative operation, it corresponds to the ECU 40 forming microcomputer for controllably switching on the glow plug 20 to the electrical load of the battery 21 to increase, a "regeneration activating device".

However, during such regenerative operation, the combustion chamber reaches 15 a high temperature. Therefore, there are concerns that the attempt to turn on the glow plug 20 for the development of heat or heat in the power elements TR leads, so the temperature of the power elements TR exceeds heat-resistant temperatures.

According to the present embodiment, to avoid the occurrence of damage to the power element TR due to the evolution of heat in a determination routine executed as in 4 to make a request as to whether the power element TR reaches a high-temperature anomaly state.

The determination routine according to 4 is an operation repeated with the microcomputer of the control IC 31 or the GDU 30 in a given cycle (of, for example, a calculation processing cycle of the control IC 31 ) is performed.

In the first step S10 the operation is in response to a power element TR from the control IC 31 supplied power-on signal, whereby a request is made as to whether the power element TR remains in an on state. If the answer to this request is YES ( S10 : YES), the routine goes to step S20 Next, which corresponds to a determining device, wherein the operation in response to a from the thermal sensor 32 in the control IC 31 input temperature detection signal is executed, whereby a request is made as to whether a temperature of the power element TR exceeds a predetermined threshold (a given temperature) which is at a high temperature.

If the answer to this request is YES ( S20 : YES), the routine goes to step S30 , which corresponds to a determination means at which a request is made as to whether the temperature of the power element TR continuously exceeds the threshold value for a period of time corresponding to a predetermined given time interval (filter period) tfil and longer. If the answer to this request is YES ( S30 : YES), it is determined that the performance element TR reaches the high-temperature anomaly state, and the routine goes to step S40 above. In step S40 which corresponds to a turn-on limiting means, the turn-on signal is forcibly switched to a turn-off state to supply the electric power to the power element TR to interrupt. It should also be noted that the determinations in steps S10 . S20 and S30 for the multitude of performance elements TR each executed. In step S40 becomes the process of stopping the supply of electric power to only the power element TR a relevant channel.

In the following step S50 leads the control IC 31 the ECU 40 a DIAG signal representing that the turn-on signal has been turned off in contrast to the command signal. In the following step S60 a request is made as to whether the temperature of the power element TR falls below the threshold. If the answer to this request is YES ( S60 : YES), the routine goes to step S70 over, where the operation is performed to the on state of the power element TR the channel concerned which has been forcibly switched off. In the following step S80 leads the control IC 31 the ECU 40 another DIAG signal representing the resumed power-up state.

With such a structure according to the present embodiment, the glow plug control device has various advantages as listed below.

(1) Since the thermal sensor 32 directly the temperature (element temperature) of the power element TR detects, an accurate element temperature can be obtained in a more reliable manner than that achieved with the control according to the prior art, in which the element temperature based on a through the power element TR flowing current value is estimated. Thus, there is no need for the power element to have excessively high heat resistance. This enables a reduction in the thermal resistance performance of the power element, or it may be sufficient that a heat radiating device such as a heat sink or the like has a reduced radiating ability.

In particular, according to the present embodiment, the glow plug 20 not only for the cold start, but also for the DPF regeneration mode switched on. Therefore, there are concerns that due to an electric current passing through the power element TR with an ambient temperature that remains under an extremely high condition, flowing to cause the associated glow plug 20 is turned on, there is a tendency that high-temperature anomalies in the power element TR occur. As described above, according to the present embodiment, it is possible to obtain the advantage with a reduction in required heat resistance performance and radiation performance.

(2) Under the circumstance in which an increasing inrush current through the glow plug 20 flows, an attempt to perform the control according to the prior art, in which the element temperatures based on the by the power element TR flowing current value, a need for providing a high current threshold value to prevent high-temperature anomalies from being determined in accordance with the inrush current. However, in a situation where a fault (such as a rare electrical short-circuit or the like) in the power element becomes TR occurs with a current flowing at a level slightly lower than the threshold, which detects electric current without determining that a high-temperature anomaly is present. Thus, there is a risk that an error in the performance element TR due to a high temperature occurs. The arrangement according to the present embodiment may deal with such failure of the power element TR deal with the rare short circuit by directly detecting the element temperature using the thermal sensor. Therefore, even if the fault occurs due to the rare short circuit, the high-temperature anomaly of the power element TR can be accurately distinguished or detected to the supply of electrical power to the power element TR to interrupt.

(3) If the performance element TR exceeds the threshold, it is then determined that the power element TR reaches the high-temperature anomaly state when the time during which the temperature of the power element exceeds the threshold is continuously exceeded during the given time interval tfil or longer. This prevents an erroneous determination from occurring due to an effect in which the temperature of the power element TR in response to a disturbance (noise) exceeds the threshold.

Second embodiment

A glow plug control device according to a second embodiment of the present invention will be described below with reference to FIG 5 described.

The glow plug control device according to the second embodiment is different from the glow plug control device according to the first embodiment with respect to various features described below. That is, with the glow plug control device according to the first embodiment, turning off the power element TR supplied turn-on signal to interrupt the supply of electrical power causes the size of the glow plug 20 supplied electric power is limited when it is determined that a high-temperature anomaly is present. In the glow plug control device according to the second embodiment, when it is determined that the high-temperature abnormality is present, the ECU 40 a control IC 31 supplied command signal for switching on the power element TR which has a smaller duty ratio (duty ratio) than a duty ratio (duty ratio) of the turn-on signal obtained from the control IC 31 the performance element TR is supplied. This allows the size of the glow plug 20 supplied electric power is reduced, thereby causing the magnitude of electric power to turn on the glow plug 20 per unit of time is limited within a given value.

More specifically, the determination operation routine becomes 4 in a sequence according to 5 changed. First, how are the operations S10 to S30 according to 4 the operations performed in a sequence to execute: a request is made as to whether the performance element TR is in the on state (step S10 ), a request is made as to the temperature of the power element TR exceeds the threshold (step S20 ), and a request is made as to whether a time during which the temperature of the power element TR exceeds the threshold value continuously during the predetermined given time interval tfil or more has elapsed (step S30 ).

If it is determined that the time has elapsed during the given time interval tfil or longer ( S30 : YES), it is subsequently determined that the power element TR remains in the high temperature anomaly state, whereupon the routine goes to step S50 passes by the control IC 31 a DIAG signal representing the determination of the high-temperature anomaly state, the ECU 40 supplies. In the following step S61 , which corresponds to a power-on limiting device, guides the control IC 31 the performance element TR a turn-on signal having a duty less than a basic duty ratio representing a duty ratio based on the command signal (see FIG. 6 (a) ) of the turn-on signal is that of the power element TR of the relevant channel determined to be involved in the high-temperature anomaly state. In addition, the reference designates t10 in 6 (a) and 6 (b) a time at which it is determined that the performance element TR remains in the high-temperature anomaly state.

In the following step S62 a request is made as to the temperature of the power element TR falls below the threshold. If the answer to this request is NO ( S62 : NO), the operation goes to step S61 fed back, in which the Einschalttastverhältnis is further reduced. If the answer to this request is YES ( S62 : YES), the routine goes to step S63 in which the turn-on ratio of the turn-on signal to the power element TR of the relevant channel, which is determined to be remaining in the high-temperature anomaly state, is increased to be larger than the current ON duty ratio.

In the following step S64 a request is made as to the temperature of the power element TR above the threshold increases. If the answer to this request is YES ( S64 : YES), the process goes to step S61 back in which the turn-on ratio of the power element TR of the relevant channel, which is determined to remain remaining in the high-temperature anomaly state, is reduced again. In contrast, if the answer to this request is NO ( S64 : NO), will step in S65 a request is made as to whether the duty ratio, which has been reduced in the previous step, has been returned to the basic duty ratio of the command signal. If the answer to this question is YES ( S65 : YES), leads the control IC 31 the ECU 40 a DIAG signal representing a normal state in the absence of a high-temperature anomaly.

From the foregoing description, it will be understood that also according to the present embodiment, which is arranged, the ON duty ratio of the power element TR during the high temperature anomaly condition, the thermal sensor reduces 32 directly the temperature of the power element TR detects why the second embodiment can have the same advantageous effects as those according to the first embodiment.

Third embodiment

A glow plug control device according to a third embodiment of the present invention will be described below with reference to FIG 7 to 10 described.

The glow plug control device according to the third embodiment is different from the glow plug control devices according to the first and second embodiments with respect to various features described below. That is, as it is in 7 is shown, the glow plug control device according to the third embodiment in addition to the glow plug 20 , which is assigned as a first electrical load, has second and third electrical loads arranged to be turned on during the DPF regeneration operation. Concrete example of the second and third electric vices 202 and 203 For example, an electric heater (for an intake air heater) for heating an intake airflow drawn into the combustion chamber, an electric heater (sheet heater) for heating a driver's seat may include an electric heater (windshield heater) attached to a rear window is attached, and an electric fan for cooling a radiator (radiator), etc. include.

Furthermore, an in 7 shown first control IC 31A same structure and function as those of 2 shown control IC 31 on. Second and third control ICs 302 and 303 respond to command signals CS2 and CS3 for generating actual turn-on signals TOS2 and Tos3 , which are supplied respectively in second and third electrical loads.

8 (a) FIG. 12 shows a state variation in the duty ratio (command duty ratio) of one of an ECU 40A the first control IC 31A supplied command signal CS1 , 8 (b) 2 shows an illustration of a DIAG signal DIAG that originates from the first control IC1 to the ECU 40A is output, and a series signal (sequence signal), which consists of four signal components corresponding to four glow plugs 20 is composed. In 8 (b) A bit # 0 indicates a start bit, and a bit # 9 indicates a stop bit. The DIAG signal DIAG In addition to the No. 0 start bit and the No. 9 stop bit, it has high-temperature anomaly signals with respect to the four power elements TR in order immediately after the start bit # 0. At the in 8 (b) In the example shown, bits Nos. 1 to 4 each assume high levels, on the basis of which it results that all four power elements TR remain in high temperature anomaly conditions.

According to the various foregoing embodiments, although upon detection of the high-temperature anomaly state, the turn-on signal is modulated to have a reduced duty cycle or to be forcibly turned off in contrast to the turn-on signal, the command signal may be reduced in duty cycle or turned off. as it is in 8 (a) is shown. At the in 8 (a) In the example shown, bits Nos. 1 to 4 of the DIAG signal are respectively set at high levels, based on which the duty ratio of the succeeding command signal CS1 is reduced in the duty cycle.

9 (b) . 9 (e) and 9 (g) provide switch-on signals TOS1 to Tos3 there, from the first to third control ICs 31 . 302 and 303 each to the first to third electrical loads 20 . 202 and 203 be issued.

9 (a) . 9 (d) and 9 (f) provide command signals CS1 to CS3 there, from the ECU 40 to the first to third control ICs 31 . 302 and 303 be issued, and 9 (c) provides a DIAG signal with an anomaly signal.

In the glow plug control apparatus according to the present embodiment, as shown in FIG 9 (a) to 9 (g) is shown at a time t0, the execution of the DPF regeneration operation, and the command signals CS1 to CS3 from turn-off states to turn-on states for turning on all of the first to third electrical loads 20 . 202 and 203 connected. Thereafter, if the high-temperature anomaly state of the power element TR increases with respect to the glow plug serving as the first electric load 20 is recorded at the time t10 an anomaly signal AS in the DIAG signal (cf. 9 (c) ) at.

Upon detection of the high temperature anomaly condition of the power element TR indicates the switch-on signal TOS1 for the relevant or relevant performance element TR a reduced turn-on duty cycle on ( 9 (b) ), where at the same time the command signals CS2 and CS3 each increased amplitudes AM1 exhibit. This allows the second and third turn-on signals TOS2 and Tos3 for the second and third electrical loads 202 and 203 increased duty cycle (relative duty cycles, duties) DI exhibit. This compensates for the reduced duty cycle of the first turn-on signal TOS1 in terms of the first electrical load 20 , This ensures that an adequate amount of electrical loads is used to prevent a speed increase that occurs when the amount of fuel injected in the main injection during the DPF regeneration operation is increased. Subsequent will be at the time t20 to which the DPF regeneration operation is terminated, the command signals CS1 to CS3 switched to off states to all of the first to third electrical loads 20 . 202 and 203 off.

In 9 (b) . 9 (d) . 9 (e) . 9 (f) and 9 (g) shown dashed lines represent the Switch-on states of the first to third electrical loads 20 . 202 and 203 in a situation where no high-temperature anomaly condition is detected.

Below is an in 10 Shown flowchart of a basic flow of a control routine for controlling the on states of the first to third electrical loads 20 . 202 and 203 described.

In the 10 The control routine shown is repeated with that in the ECU 40A Built-in microcomputer running for a given cycle.

First, in step S100 an inquiry is made as to whether the diesel engine is in a period in which it is necessary to perform the DPF regeneration operation. If the answer to this request is YES ( S100 : YES), gives in the following step S101 the ECU 40A the first command signal CS1 (hereinafter referred to as "turn-on command") to the first control IC 31 out.

In the following step S105 a request is made as to whether the performance element TR falls into the high-temperature anomaly state. In carrying out such a request, the ECU 40A be adapted to obtain a detected temperature signal from the thermal sensor 32 the control IC 31 is supplied, whereupon the microcomputer of the ECU 40A performs the operation on the basis of such a detected temperature signal to make a request as to whether the power element TR falls into the high-temperature anomaly state. According to another alternative, the first control IC 31 be configured to determine the presence of a Hochtemperaturanomalie based on such a detected temperature signal to prepare a DIAG signal, which in turn to the ECU 40A is sent. In this case, the microcomputer procures the ECU 40A a determination result regarding the presence of the high-temperature anomaly contained in the DIAG signal.

If it is determined that there is no high-temperature anomaly ( S105 : NO), then send in the subsequent step S110 the ECU 40A a normal turn-on command to the second control IC 302 to cause the second electrical load 202 is turned on at a predetermined ON duty ratio for normal operation. Continue to send in step S111 the ECU 40A another normal power-on command to the third control IC 303 to cause the third electrical load 203 is turned on at the predetermined ON duty ratio for normal operation.

The first control IC performs 31 in addition to the routine according to 10 in the 5 shown operating routine. Accordingly, during the occurrence of the high-temperature anomaly, execution of the operation in step 61 according to 5 to the consequence that the turn-on ratio of the glow plug 20 is made lower than the basic duty cycle based on the command signal. If it is determined in the current routine that the high temperature anomaly is in the power element TR is available ( S105 : YES), procured in S120 the first control IC 31 a turn-on decrement with a reduced duty cycle compared to the basic duty cycle. For example, causing the first control IC 31 a DIAG signal with such power-on decrement to the ECU 40A sends, the ECU 40A a procurement of the decrement described above.

In the following step S121 becomes a turn-on increment for the second and third electrical loads 202 and 203 based on in step S120 calculated switch-on decrement calculated. The turn-on increment is determined to compensate the turn-on decrement just enough. Assuming that with all glow plugs 20 For example, if the duty cycles have been set to zero, the turn-on increment may preferably be set at a range of 100 watts to 400 watts or in a range of 25 watts to 400 watts.

In the following step 130 sends the ECU 40A an incremented turn-on command (incrementation turn-on command) to the second control IC 302 to the second electrical load 202 with a turn-on duty ratio that is increased from a normal duty cycle rate for the normal operating state by the turn-on increment. In step S131 send the ECU 40 another incremented power-on command to the third control IC 303 to turn on the third electrical load 203 with a duty cycle ratio increased from the normal duty cycle rate for the normal operating state by the turn-on increment.

In the following step S170 a request is made as to whether the end time has come when the DPF regeneration operation is completed to complete the ON operation for the DPF regeneration operation. If it is determined that the end time is present to terminate the power-on operation for the DPF regeneration operation ( S170 : YES), in the following step S180 Enabling end commands to the first to third control ICs 31 . 302 and 303 sent to the turn-on states of the first to third electrical loads 20 . 202 and 203 to interrupt. In contrast, if it is determined that there is no end time for completing the power-on operation for the DPF regeneration operation ( S170 : NO) or if in step S100 it is determined that DPF regeneration is not required at this time ( S100 : NO), the process goes to step S100 recycled.

From the foregoing description, it will be understood that present embodiments have the same advantageous effects as those of the other various embodiments described above. In addition, the glow plug 20 is turned on at a reduced duty ratio when the high-temperature abnormality occurs during the DPF regeneration operation, resulting in the ability of the occurrence of a by turning on the glow plug 20 in a high temperature environment caused thermal damage to the power element TR is avoided.

According to the present embodiment, further, under a circumstance in which the high-temperature abnormality occurs during the DPF regeneration operation, the glow plug 20 switched on with a reduced turn-on ratio. Thus, the turn-on increment of the other electrical loads 202 and 203 compensate the switch-on decrementing of the first electrical load. This allows for adequately suppressing the occurrence of a speed increase during execution of the DPF regeneration operation.

Fourth embodiment

A glow plug control device according to a fourth embodiment of the present invention will be described below with reference to FIG 11 and 12 described.

In the glow plug control device according to the third embodiment, when the high-temperature abnormality occurs during the DPF regeneration operation, the glow plug becomes 20 switched on with the reduced turn-on ratio. To compensate for such turn-on decrement, the electrical loads become 202 and 203 switched on with increased power-up ratio. In this case, the turn-on duty ratio becomes for the plurality of electrical loads 202 and 203 incremented at the same time.

In contrast, in the glow plug control device according to the present embodiment, the turn-on increments of the second and third electric loads 202 and 203 initiated alternately.

Such a feature will be described in more detail below with reference to FIG 11 described. First, be at t0 to which the operation of the DPF regeneration operation starts, the command signals switched from the turn-off states to the turn-on states to all of the electrical loads 20 . 202 and 203 turn. If thereafter, the high-temperature anomaly state of the power element TR or the glow plugs 20 that serves as the first electrical load at the time t10 is detected, an anomaly signal rises in the DIAG signal (see FIG. 11 (c) ).

Upon detection of the high-temperature anomaly, the on-duty ratio of the relevant power element becomes TR reduced (cf. 11 (b) ) and simultaneously becomes the command duty ratio for the second electrical load 202 increases to compensate for the reduction in the duty cycle of the relevant power element TR. Subsequent will be at t11 the command duty ratio for the second electric load 202 returned to a normal value while the command duty ratio for the third electrical load 203 is increased. This makes it possible to ensure an adequate magnitude of the electric load for suppressing the speed increase caused by performing the main injection with the increased fuel volume during the DPF regeneration operation. Subsequent will be at the time t20 to which the DPF regeneration operation is terminated, all command signals are switched to off states to all of the electrical loads 20 . 202 and 203 off.

Below is a control routine for controlling the on states of the electrical loads 20 . 202 and 203 in more detail and with reference to an in 12 shown flowchart described.

The one in the ECU 40A contained microcomputer repeatedly performs the control routine according to 12 for a given cycle.

First, the same operations will be in the steps S100 to S121 like those according to 10 executed. That is, if it is determined that DPF regeneration is not required ( S100 : YES), sends the ECU 40A the turn-on command to the first control IC 31 to the glow plug 20 to turn on ( S101 ). If it is determined that no High temperature anomaly condition is present ( S105 : NO), sends the ECU 40A the normal power on commands to the second and third control ICs 302 and 303 ( S110 and S111 ). On the other hand, if it is determined that the high-temperature anomaly condition exists ( S105 : YES), procures the ECU 40A Information regarding switch-on decrementing for the glow plug 20 ( S120 ). Then the ECU calculates 40A the turn-on increments for the second and third electrical loads 202 and 203 on the basis of the procured switch-off decrement ( S121 ).

In the following step S125 a request is made as to whether the second control IC 302 is in a duty cycle rate incrementing period determined as a time duration for increasing the duty cycle rate for the second electric load. If it is determined that the second control IC 302 is in a power-on increment time ( S125 : YES), gives in the following step S130 the ECU 40A a duty ratio rate incrementing command to the second control IC 302 off to the second electrical load 202 with an incremented on-duty ratio higher than the turn-on duty ratio for normal operation by the turn-on increment. On the other hand, if it is determined that the second control IC 302 is not in the duty cycle rate increment time period ( S125 : NO), gives in the following step S131 the ECU 40A another duty ratio rate incrementing command to the third control IC 303 off to the third electrical load 203 with a turn-on duty ratio greater than the turn-on duty cycle for normal operation by the turn-on increment.

In the following step S170 A request is made as to whether the timing has come at which the DPF regeneration operation is completed, and the ON operation for the DPF regeneration operation is finished. If it is determined that the timing for completing the power-on operation for the DPF regeneration operation has come ( S170 : YES), sends the ECU 40A in the following step S180 the power-on stop command to the control ICs 31 . 302 and 303 to the on states of the electrical loads 20 . 202 and 203 to interrupt. On the contrary, if it is determined that the timing for ending the switch-on operation for the DPF regeneration operation has not come ( S170 : NO) or if in step S100 it is determined that this is not the time for the power-on operation for the DPF regeneration operation ( S100 : NO), the process goes back to the process in S100 guided.

In the glow plug control apparatus according to the above-described embodiment, if the high-temperature abnormality occurs during the DP regeneration operation, the on-load duty ratio of the glow plug becomes 20 reduced. This prevents the occurrence of thermal damage to the power element TR by turning on the glow plug 20 is caused in the high temperature environment. Further, according to the present embodiment, the on-duty ratio of the power element becomes TR decreases when the high temperature anomaly is present during the DPF regeneration operation. In such a case, turn-on decrementing is done by alternately increasing the turn-on duty ratio rates of the other electrical loads 202 and 203 compensates, which adequately suppresses the speed increase caused during the DPF regeneration operation.

Fifth embodiment

A glow plug control device according to a fifth embodiment of the present invention will be described below with reference to FIG 13 and 14 described.

In the glow plug control devices according to the second to fourth embodiments, when the high-temperature anomaly occurs during the DPF regeneration operation, the on-load duty ratio of the glow plug becomes 20 decreases and becomes the Einschaltdekrementierung the glow plug by increasing the Einschalttastverhältnisraten the electric load 202 and 203 compensated.

In contrast, according to the present embodiment, the ECU 40A set up to detect a high-temperature anomaly (at the time t10 ) to operate such that, once the execution of the DPF regeneration operation is interrupted, all electrical loads 20 . 202 and 203 be turned off (at the time t12 ).

13 (b) . 13 (e) and 13 (g) provide switch-on signals TOS1B to TOS3B there, from the first to third control ICs 31 . 302 and 303 each of the first to third electrical loads 20 . 202 and 203 be supplied.

13 (a) . 13 (d) and 13 (f) provide command signals CS1B to CS3B there, the first to third control ICs 31 . 302 and 303 from the ECU 40A be supplied, and 13 (c) shows a DIAG signal with an anomaly signal.

As it is in 13 (b) shows when detecting a high temperature anomaly t10 a DIAG signal has an anomaly signal ASB on it as in 13 (c) is shown. At this point, the ECU sends 40A a command signal CS2B to the second control IC 302 (Comp. 7 ), which in turn is a signal TOS2B to the second electrical loads 202 supplies. At the same time the ECU sends 40A a command signal CS3B to the third control IC 303 , which in turn is a turn-on signal TOS3B to the third electrical load 203 supplies. The second and third off signals TOS2B and TOS3B have falling edges at the time t12 on, which is why all of the electrical loads 20 . 202 and 203 turned off.

Below is a control routine for controlling the on states of the electrical loads 20 . 202 and 203 in more detail and with reference to an in 14 shown flowchart described.

The one in the ECU 40A included microcomputer leads the in 14 shown control routine for a given cycle.

First, in the steps S100 to S121 a request is made as to whether there is currently a period or period for turning on the DPF regeneration operation. If it is determined that the time for switching on the DPF regeneration operation has come or has come ( S100 : YES), sends the ECU 40A in the following steps S102 Command signals (turn-on commands) to the first to third control ICs 31 . 302 and 303 each to turn on all electrical loads 20 . 202 and 203 ,

If in the following step S105 it is determined that there is no high-temperature anomaly state ( S105 : NO), the operation of step S102 continuously executed to continue sending the power-on commands until in the following S170 it is determined that there is a power-on end point to complete the DPF regeneration operation. Upon determination that the turn-on end time has come to end the DPF regeneration operation ( S170 : YES), sends in the following step S180 the ECU 40A the power-on command to the control ICs 31 . 302 and 303 for interrupting the switch-on states of all electrical loads 20 . 202 and 203 ,

On the contrary, if it is determined that no high-temperature anomaly occurs during the DPF regeneration operation ( S105 : YES), sends in the following step S140 the ECU 40A Command signals (power-on commands) to the control ICs 31 . 302 and 303 to interrupt the switch-on states of all electrical loads 20 . 202 and 203 ,

In the glow plug control apparatus according to the above-described present embodiment, when the high-temperature abnormality occurs during the DPF regeneration operation, the on-state of the glow plug becomes 20 interrupted. This prevents the occurrence of one by turning on the glow plug 20 under the high temperature environment caused thermal damage to the power element TR , Also, according to the present embodiment, when the high-temperature abnormality occurs during the DPF regeneration operation, execution of the DPF regeneration operation is once stopped. This allows the temperature (element temperature) of the power element TR is further decreased immediately than is attained when the DPF regeneration operation is continuously decreasing the ON duty ratio or interrupting the ON state of the glow plug 20 is achieved.

Sixth embodiment

A glow plug control device according to a sixth embodiment of the present invention will be described below with reference to FIG 13 and 14 described.

In the glow plug control devices according to the second to fourth embodiments, when the high-temperature anomaly occurs during the DPF regeneration operation, the on-load duty ratio of the glow plug becomes 20 decreases and becomes the turn-on decrement of the glow plug 20 by increasing the duty cycles of the electrical loads 202 and 203 compensated.

According to the present embodiment according to 15 on the other hand is the ECU 40A set up in such a way, all of the electrical loads 20 . 202 and 203 for a longer period of time (time period) between times t0 and t21 turn on than those in which the electrical loads 20 . 202 and 203 be turned on if no high-temperature anomaly is detected.

15 (b) . 15 (e) and 15 (g) provide switch-on signals TOS1C to TOS3C there, from the first to third control ICs 31 . 302 and 303 each of the first to third loads 20 . 202 and 203 be supplied.

15 (a) . 15 (d) and 15 (f) provide command signals CS1C to CS3C there, from the ecu 40A the first to third control ICs 31 . 302 and 303 be supplied, and 15 (c) shows a DIAG signal with an anomaly signal ASC.

As it is in 15 (b) shown when detected a high-temperature anomaly at t10 a DIAG signal an anomaly signal ASC with a rising edge and a falling edge, each at t10 and t21 occur. Upon receipt of the DIAG signal, the first control IC transmits 31A a switch-on signal TOS1C for switching on the first electrical load 20 (Comp. 7 ) with a reduced duty cycle rate during the period (period) t0 and t21 as it is in 15 (c) is shown. At this point, the ECU sends 40A a command signal CS2C to the second control IC 302 (Comp. 7 ), which in turn is a signal TOS2C the second electrical load 202 supplies. At the same time the ECU sends 40A a command signal CS3C to the third control IC 303 , which in turn is a turn-on signal TOS3C to the third electrical load 203 supplies. The second and third off signals TOS2B and TOS3B have falling edges at the time t21 on, which is why all of the electrical loads 20 . 202 and 203 remain continuously on for an extra time interval, unlike a case where no high temperature anomaly is detected.

Below is a control routine for controlling the on states of the electrical loads 20 . 202 and 203 referring to a in 16 shown flowchart described.

The one in the ECU 40 contained microcomputer repeatedly performs the control routine according to 16 for a given cycle.

First, in step S100 a request is made as to whether or not there is a period (period) for turning on the DPF regeneration operation. If it is determined that there is the time to turn on the DPF regeneration operation ( S100 : YES), sends in the following step S102 the ECU 40A Command signals (turn-on commands) to the first to third control ICs 31 . 302 and 303 each for switching on one of the electrical loads 20 . 202 and 203 ,

If in the following step S105 it is determined that there is no high-temperature anomaly state ( S105 : NO), the operation in step S102 continuously executed to continue sending the power-on commands until the next step S170 it is determined that the turn-on end time is present for terminating the DPF regeneration operation. Upon determination that the turn-on end point is present to terminate the DPF regeneration operation ( S170 : YES), sends in the following step S180 the ECU 40A the power-on commands to the control ICs 31 . 302 and 303 for interrupting the switch-on states of all electrical loads 20 . 202 and 203 ,

In contrast, if it is determined that the high-temperature anomaly occurs ( S105 : YES), then procure in the following step S120 the ECU 40A Information regarding the turn-on decrement of the glow plug 20 in the same way as in step S120 according to 10 , In the following step S150 calculates the ECU 40A a Einschaltextrazeit for the second and third electrical loads 202 and 203 based on information regarding the power-on decrement generated in step S120 has been procured. Thus, the ECU performs 40A the operation for updating the timing at which the DPF regeneration operation is terminated and the ON operation for the DPF regeneration operation is completed, to a new time delayed by the extra time calculated,. That is, the power-on end time corresponding to the in S170 is used, is delayed. In addition, when the DPF regeneration operation time is delayed, the temperature of the exhaust gases may preferably be carried out by performing a main injection with a reduced fuel volume to reduce the degree of temperature rise to facilitate a temperature drop of the power element TR.

In the glow plug control apparatus according to the present embodiment described above, the on-duty ratio is decreased when the high-temperature abnormality is present during the DPF regeneration operation. This prevents the occurrence of thermal damage to the power element TR when turning on the glow plug 20 caused under the high temperature environment. In addition, the extension of the DPF regeneration operating time depending on the turn-on decrementing of the glow plug 20 in connection with the extension of the turn-on periods of the other electrical loads 202 and 203 adequately achieving the suppression of the speed increase during the DPF regeneration operation.

Seventh embodiment

Hereinafter, a glow plug control device according to a seventh embodiment of the present invention with reference to 17 and 18 described.

In the glow plug control devices according to the second to sixth embodiments, all electrical loads 20 . 202 and 203 during the DPF regeneration operation is turned on, whereby the speed increase is suppressed. In contrast, according to the in 17 1, during the DPF regeneration operation, only the glow plug is shown 20 switched on, the other electrical loads 202 and 203 remain off, and when the high-temperature anomaly is detected, at that time t10 the other electrical loads 202 and 203 switched on.

17 (b) . 17 (e) and 17 (g) provide switch-on signals TOS1D to TOS3D each of the first to third control ICs 31 . 302 and 303 to the first to third electrical loads 20 . 202 and 203 be issued.

17 (a) . 17 (d) and 17 (f) provide command signals CS1D to CS3D from the ECU 40A to the first to third control ICs 31 . 302 and 303 be issued and shows 17 (c) a DIAG signal with an anomaly signal ASD ,

As it is in 17 (b) shows, if too t10 a high-temperature anomaly is detected, a DIAG signal the anomaly signal ASD at which a rising edge and a falling edge at t10 and t20 each occurs. Upon receipt of the DIAG signal, the first control IC transmits 31A the switch-on signal TOS1D for switching on the first electrical load 20 (Comp. 7 ) with a reduced duty cycle rate during the time period t0 to t20 as it is in 17 (c) is shown. At this point, the ECU sends 40A a command signal CS2D to the second control IC 302 (Comp. 7 ), which in turn is a turn-on signal TOS2D the second electrical load 203 supplies. At the same time the ECU sends 40A a command signal CS3D to the third control IC 303 , which in turn is a turn-on signal TOS3D the third electrical load 203 supplies. The second and third off signals TOS2D and TOS3D have falling edges at the time t20 on, which is why only the glow plug 20 is switched on, whereas the other electrical loads 202 and 203 turned off. In addition, if too t10 the high temperature anomaly is detected, the other electrical loads 202 and 203 switched on. Below is a control routine for controlling the on states of the electrical loads 20 . 202 and 203 further referring to 18 shown flowchart described.

The one in the ECU 40 contained microcomputer repeatedly performs the control routine according to 18 for a given cycle.

First, in the steps S100 to S105 . S120 and S121 the same operations as those according to 10 executed. That is, if it is determined that there is a turn-on period for the DPF regeneration operation ( S100 : YES), the ECU 40A the turn-on command to the first control IC 31 to turn on the glow plug 20 Posted ( S101 ). If it is determined that there is a high-temperature anomaly ( S105 : YES), procures the ECU 40A the switch-on decrementing of the glow plug 20 ( S120 ) and calculates the duty cycles of the second and third electrical loads 202 and 203 on the basis of the procured switch-off decrement ( S121 ). These turn-on duty ratios are determined to have values indicative of the turn-on decrement of the glow plug 20 compensate exactly (without excess or deficit).

First, send in step S160 the ECU 40A a power-on command to the second control IC 302 for switching on the second electrical load 202 with one in step S121 calculated duty cycle rate. Additionally sends in the following step S161 the ECU 40A another turn-on command to the third control IC 303 to turn on the third electrical load 203 with an in S121 calculated duty cycle rate.

In the following step S170 a request is made as to whether there is an end time for the completion of the DPF regeneration operation and for the turn-on operation for completing the DPF regeneration operation. If it is determined that the end time is at the end of the DPF regeneration operation ( S170 : YES), sends in the following step S180 the ECU 40A Turn on commands to the control ICs 31 . 302 and 303 for the termination of the switch-on states of all electrical loads 20 . 202 and 203 , However, if it is determined that there is no end time for the DPF regeneration operation ( S170 : NO) or if it is determined that DPF regeneration is not required ( S100 : NO), the process goes to step S100 recycled.

If, in contrast, in step S105 it is determined that there is no high temperature anomaly ( S100 : NO), the process goes to step S170 in which there are no turn-on commands to the second and third control ICs 302 and 303 be sent as the operations in step S160 and S161 , That is, when there is no high-temperature anomaly condition, even during the DPF regeneration operation-on period, there are no turn-on operations of the second and third electric loads 202 and 203 be executed.

In the above-described glow plug control apparatus according to the present embodiment, the on-load duty ratio of the glow plug is reduced when the high-temperature abnormality is present during the DPF regeneration operation. This prevents the occurrence of thermal damage to the power element TR when turning on the glow plug 20 caused under the high temperature environment. In addition, according to the present embodiment, in the presence of a high-temperature anomaly during the DPF regeneration operation, the on-load duty ratio of the glow plug becomes 20 reduced. In this case, the turn-on decrement of the glow plug 20 by Turning on the operation of the second and third electrical loads 202 and 203 compensated. This adequately suppresses the speed increase caused by the DPF regeneration operation. Further, according to the present embodiment, when there is no high-temperature anomaly condition, there are no turn-on operations of the second and third electric loads 202 and 203 even during the DPF regeneration operation start time. This prevents the second and third electrical loads 202 and 203 be actuated at a time not intended by a vehicle occupant, thereby preventing the vehicle driver from feeling uncomfortable.

Eighth embodiment

A glow plug control device according to an eighth embodiment of the present invention will be described below with reference to FIG 19 (a) to 19 (d) described.

In the glow plug control apparatus of the various embodiments described above, when the glow plug is turned on 20 during the DPF regeneration operation, from the control IC 31 to the performance element TR issued turn-on signal on a duty cycle, the fast step by step at the time t0 rises, as for example in 11 (b) is shown. Increasing the duty cycle in such a manner (see FIG. 11 (b) ) leads to the appearance of an inrush current passing through the glow plug 20 flows, with a consequent increase in electrical power consumption for a few seconds (cf. 19 (a) ). However, when the glow plug is switched on, it increases 20 during the execution of the DPF regeneration operation, the electric power consumption due to the occurrence of the inrush current occurs, and a variation in the magnitude of the electric load takes place. This results in the occurrence of a fluctuation in the rotational speed during a phase of suppressing the speed increase during the execution of the DPF regeneration operation.

In the glow plug control apparatus according to the present embodiment, on the other hand, a duty ratio of a power-on signal supplied to the power element TR is gradually increased (see FIG. 19 (d) ) when turning on the glow plug 20 when starting the DPF regeneration operation. Thus, the glow plug points 20 no fluctuation in the electric power consumption due to the inrush current, and the electric power consumption becomes a fixed level between a power-on start time t0 and a power-on time t20 maintained (see. 19 (c) ). Furthermore, according to an alternative, the ECU 40A such that as the duty ratio is gradually increased in the above-described manner, the duty ratio of the turn-on signal applied to the power element TR can be gradually increased in a predetermined pattern to enable the glow plug 20 has a fixed electrical power consumption. In such an alternative, the duty cycle of the turn-on signal applied to the power element TR may be gradually increased with a given time constant.

According to the present embodiment described above, when the glow plug is turned on 20 During the execution of the DPF regeneration operation, it is possible to prevent the occurrence of a fluctuation in the magnitude of the electric load, thereby coping with the problem of the fluctuation in the rotational speed.

Ninth embodiment

A glow plug according to a ninth embodiment of the present invention will be described below with reference to FIG 20 described.

According to the first embodiment described above, the one in the ECU 40 microcomputer arranged to form the "regeneration activating means" for controllably switching on the glow plug to cause the electric load of the battery 21 increases. That is, the microcomputer of the ECU 40 commands to turn on the glow plug 20 during the execution of the DPF regeneration operation.

According to the in 20 On the other hand, the present embodiment shown has a GDU 30A a microcomputer 35A which has the "regeneration activation device". That is, the microcomputer 35A the GDU 30A commands to turn on the glow plug 20 during the execution of the DPF regeneration operation.

According to the first embodiment, furthermore, the control IC 21 that the operation in S40 according to 4 is executed, the "Einschaltbegrenzungseinrichtung" for performing the control for interrupting the on state of the power element TR in response to that from the thermal sensor 32 perform supplied temperature detection signal. Information regarding such a limiting operation is given to the ECU 40 supplied as the DI AG signal.

In contrast, in the structure according to the present embodiment according to 20 a temperature detection signal T1 that from the thermosensor 32 a control IC 31A the GDU 30A is supplied to the microcomputer 35A the GDU 30A supplied as a DIAGA signal. Upon receiving such a DIAG signal DIAGA, the microcomputer outputs 35A the GDU 30A a command signal CSA for interrupting the on state of the power element TR in response to the acquired temperature detection signal T1 out.

In summary, the operations performed by the microcomputer of the ECU according to the first embodiment 40 be executed, according to the present embodiment by the microcomputer 35A the GDU 30A executed.

Further embodiments

The various embodiments described above may be implemented in various modified forms as listed below. Furthermore, the present invention is not limited to the contents of the descriptions of the above-described embodiments, and the different structures according to the various embodiments as described above may be implemented in arbitrarily varied combinations.

Although the various embodiments have been described above with reference to the structures in which the thermal sensor 32 on the power element TR is attached, the present invention is not limited to such structures, and may be the thermal sensor 32 for example, on the control IC 31 or the metal plate 33 be attached. Furthermore, in the case where the thermal sensor 32 on the control IC 31 is attached, the wire bonding for connecting the control IC 31 and the thermosensor 32 eliminated each other. Furthermore, in another case where the thermal sensors 32 on the performance elements TR are attached, an inquiry can be made as to whether the high temperature anomaly occurs at each of the plurality of power elements TR is available.

When the high-temperature anomaly is detected at a time of starting the DPF regeneration operation or during the execution of the DPF regeneration operation, the execution of the DPF regeneration operation may be interrupted once, and after a drop in the temperature of the power element TR When a given time interval elapses, the DPF regeneration operation can be performed again.

For switching on the electrical loads 20 . 202 and 203 During the DPF regeneration operation, the on-load duty ratios of the electrical loads 20 . 202 and 203 be set up such that they are lower than those of the electrical loads 20 . 203 and 203 which are used for another application except the DPF regeneration mode. This achieves a reduction in noise (noise, noise) caused by the operation of electrical loads 20 . 202 and 203 caused, for example, by electric fans during the DPF regeneration operation, whereby a reduction in uncomfortable feeling is achieved in a vehicle occupant.

Although the first embodiment according to 1 has been described as being that of a DPF unit 19a As a cleaning device, the cleaning device may be in addition to the DPF unit 19a an NOx catalyst for purifying NOx components in exhaust gases or an oxidizing catalyst for purifying HC and CO in exhaust gases, etc. Since these catalysts operate under conditions that are activated at high temperatures, the electrical loads become 20 . 202 and 203 is turned on as the speed-up suppressing means when the amount of fuel injected in the main injection is increased not for the regenerative operation but for an activation treatment.

According to the various embodiments described above, in support of an initial ignitability when starting the diesel engine 10 the glow plug 20 switched on (as a start glow), in addition to the glow plug 20 is turned on during execution of the DPF regeneration operation. Alternatively, not just the glow plug 20 during the execution of the DPF regeneration operation is turned on, but afterglow may be performed as described below. That is, when applied to a diesel engine having a low compression ratio or when causing the diesel engine 10 operated at high altitude with thin air, even if the diesel engine 10 is started with the glow at engine start, an interruption of the operation of the glow plug 20 in a subsequent stage, the risk of the occurrence of a misfire in the combustion chamber. To avoid such a risk, after the start glow has been performed for a given time interval (of, for example, approximately 5 minutes), the glow plug may be fired 20 preferably (as an afterglow) for a given post-start period (of, for example, approximately 5-10 min.) to complete the combustion.

According to the various embodiments described above, the thermal sensor detects 32 directly the temperature (element temperature) of the power element TR to the operation in response to that from the thermosensor 32 however, the present invention is not limited to a structure in which such a thermal sensor 32 is applied. For example, a detection circuit for detecting the turn-on duty ratio of the glow plug 20 be provided to perform an operation in response to the detected Einschalttastverhältnisrate so that a request is made whether a Hochtemperaturanomalie is present.

There are disclosed a glow plug control device and a glow plug control system, comprising: a power element (switching element) that turns on a glow plug provided in a combustion chamber of a diesel engine, a control IC for controlling the operation of the power element, and a thermal sensor (temperature detecting device) that detects the temperature of the Performance element recorded. The control IC has a cut-in limiting means which limits a turn-on duty ratio of the glow plug in the presence of a high-temperature abnormality when the temperature detected by the thermal sensor exceeds a predetermined given temperature.

Claims (14)

A glow plug control device applied to an internal combustion engine (10) having glow plugs (20) mounted in combustion chambers (15) of the internal combustion engine and a filter device (19a) for trapping particulates in exhaust gases, the glow plug control device characterized by: regeneration activating means (44; 35A) for controllably turning on an electric load such that an electric load of a battery (21) charged by the internal combustion engine during execution of a regeneration operation of the filter device (19a) for raising exhaust gas temperatures is trapped around trapped particles to remove from the filter device, Switching elements (TR) for respectively switching on and off the glow plugs (20), a turn-on control means (31; 31A) for controlling turn-on operations of the switching elements, and determining means (S20) for determining whether a high-temperature anomaly condition is present at which temperatures of the switching elements exceed a predetermined given temperature, wherein the glow plugs (20) are turned on during startup of the internal combustion engine (10) and are also turned on to serve as the electrical load during execution of the regeneration operation of the filter device (19a), and wherein the turn-on control means (31; 31A) includes a turn-on limiting means (S40; S61) for limiting turn-on duty ratio of the glow plugs when the determining means determines that the high-temperature anomaly condition exists. Glow plug control device according to Claim 1 further characterized by temperature sensing means (32) for sensing the temperature of the switching element, the determining means (32) responsive to the temperature sensed by the temperature sensing means for determining whether the high temperature anomaly condition is present. Glow plug control device according to Claim 1 or 2 characterized in that: the regeneration activating means (44; 35A) executes turn-on control on a plurality of electric loads including the glow plugs during execution of the regeneration operation, and the regeneration activating means (44; 35A) turns-on duty ratios of other electrical loads except for the glow plugs in the presence of the high-temperature anomaly condition increases to levels greater than those of the electrical loads for normal operation. Glow plug control device according to Claim 3 characterized in that the other electrical load has a plurality of other electrical loads, and the regeneration activating means (44; 35A) simultaneously increases on-duty ratios of the plurality of other electrical loads in the presence of the high temperature anomaly condition. Glow plug control device according to Claim 3 characterized in that the other electrical load has a plurality of other electrical loads, and the regeneration activating means (44; 35A) alternately increases on-duty ratios of the plurality of other electrical loads to increase the on-duty ratio of one of the plurality of other electrical loads in the presence of the high-temperature anomaly condition to increase. Glow plug control device according to one of Claims 3 to 5 characterized in that the regeneration activating means (44; 35A) stops switching on the other electrical loads for normal operation even when the high temperature anomaly condition exists. Glow plug control device according to one of Claims 1 to 6 characterized in that the regeneration activating means (44; 35A) expands an on-time interval of the electric load in the presence of the high-temperature anomaly condition to a value larger than that of the normal-load electrical load. Glow plug control device according to Claim 1 or 2 characterized in that the regeneration activating means (44; 35A) delays the execution of the regeneration operation when the high temperature anomaly condition exists. Glow plug control device according to one of Claims 1 to 8th characterized in that the power-on limiting means (S40; S61) limits the on-load duty ratio by turning off the switching element or by reducing a duty ratio. Glow plug control device according to one of Claims 1 to 9 characterized in that the turn-on control means (31) controls the operation of the switching means based on a command signal outputted from the command control device, and when the turn-on limiting means executes a turn-on limitation as opposed to a command content of the command signal, the turn-on control means sends a DIAG signal to the command control device outputs the execution of the switch-on limit. Glow plug control device according to Claim 10 characterized in that the internal combustion engine has a plurality of cylinders formed with the combustion chambers to which the glow plugs are attached, and the turn-on control means (31) outputs the DIAG signal for each of the glow plugs. Glow plug control device according to one of Claims 1 to 10 further characterized by switching elements for turning on and off the glow plugs, and wherein at the start of turning on the glow plugs with the execution of the regeneration operation on-duty ratios of the switching elements are gradually increased. Glow plug control device according to one of Claims 1 to 12 characterized in that the glow plugs are turned on to assist an initial ignitability of the internal combustion engine during starting thereof, and are also turned on to stabilize combustion in the internal combustion engine during a post-start period. Glow plug control system with at least one of the glow plugs and the filter device and the glow plug control device according to one of Claims 1 to 13 ,

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