EXHAUST AIR CONTROL DEVICE
Patent Information
- Authority / Receiving Office
- DE · DE
- Patent Type
- Patents
- Current Assignee / Owner
- SUZUKI MOTOR CORP
- Filing Date
- 2019-02-01
- Publication Date
- 2026-07-09
AI Technical Summary
Existing exhaust emission control devices that regenerate collection filters for particulate matter in vehicle engines often impact fuel efficiency due to increased engine operations.
An exhaust emission control device that includes a control device to stop fuel injection and/or ignition at predetermined intervals based on engine speed and load, facilitating filter regeneration without affecting fuel efficiency.
The device effectively regenerates collection filters by increasing component temperatures naturally, thus maintaining fuel efficiency and reducing fuel consumption.
Smart Images
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Abstract
Description
Technical field
[0001] The present invention relates to an exhaust emission control device. Background of the invention
[0002] In some vehicle engines, collection filters for collecting suspended particles (particulate matter) contained in exhaust gas are installed as part of exhaust emission control devices. A technology for regenerating such a collection filter by facilitating the combustion of suspended particles if a predetermined quantity of suspended particles accumulates in the collection filter has been proposed (see patent specification 1).
[0003] According to patent specification 1, a step to increase the temperature of exhaust gas, which affects the collection filter, and a step to adjust the intake air quantity and the fuel injection quantity for the engine to facilitate combustion of the suspended particles collected in the collection filter are frequently switched at predetermined times.
[0004] Patent specification 1: Japanese patent application Publication no. 2004-190641 A
[0005] According to patent specification 1, the engine speed or engine load is increased or amplified to regenerate the collection filter. However, this can have an impact on fuel efficiency. Summary of the invention
[0006] It is therefore an object of the present invention to provide an exhaust emission control device that is able to regenerate a collection filter that collects suspended particles in a suitable manner without affecting fuel efficiency.
[0007] According to one aspect of the embodiments of the present invention, an exhaust emission control device is provided comprising a collection filter configured to collect soot emitted by an engine and a control device configured to control a fuel injection device and an ignition device, wherein the control device performs a filter regeneration facilitation control to halt fuel injection and / or ignition at a predetermined time interval within a regeneration facilitation range of a control map defined on the basis of an engine speed and an engine load.
[0008] According to the present invention, a collection filter that collects suspended particles can be regenerated in a suitable manner without affecting fuel efficiency. List of characters Fig. Figure 1 is a view showing the overall configuration of an engine control system according to an exemplary embodiment; Fig. 2 is a view that represents a control mapping based on engine speed and engine load; Fig. Figure 3 is a view that shows an example of a GPF regeneration control flow according to the embodiment; Fig. Figure 4 is a view that represents an example of a filter regeneration facilitation flow according to the embodiment; Fig. Figure 5 is a view that illustrates an example of a filter regeneration facilitation control flow according to the embodiment; and Fig. Figure 6 is a time graph showing a change in the GPF temperature (exhaust gas temperature) according to the embodiment. Detailed description of the exemplary implementations
[0009] An embodiment of the present invention is described in detail below with reference to the accompanying drawings. Furthermore, a description is given below with reference to a four-wheeled vehicle as an example of a vehicle in which an engine control system according to the present invention is applied; however, the subject matter of the application is not limited thereto and may be modified. For example, the present invention may also be applied to other types of vehicles, such as two-wheeled vehicles.
[0010] With reference to Fig. 1 The engine control system is described according to the present embodiment. Fig. Figure 1 is a view showing the overall configuration of the engine control system according to the present embodiment. However, the engine control system is not limited to the configuration described below and can be modified as appropriate.
[0011] As in Fig. Shown in 1 is an engine control system 1 configured according to the present embodiment to perform the operations of a motor 2 , which is an internal combustion engine, and its peripheral components are controlled by an ECU 3 to control the (Electronic Control Unit). 3 consists of a control device of the present invention, as described in detail below. The motor 2 It is configured with, for example, a multi-cylinder DOHC engine of a direct-acting type (DOHC: "Double Overhead Camshaft"; two overhead camshafts). The engine 2is configured to accommodate a crankshaft housed in a crankcase (not shown in the figures) 20 , a cylinder 21 , a cylinder head 22 etc.
[0012] In the cylinder 21 is a piston 23 recorded in such a way that it can move back and forth in a predetermined direction (in Fig. 1 up and down). The crankshaft 20 and the piston 23 are connected by a connecting rod 24 connected to each other. In the engine 2 the piston moves 23 back and forth in the predetermined direction, thereby rotating the crankshaft 20 via the connecting rod 24 is being filmed.
[0013] The interior of the cylinder head 22 represents a combustion chamber 25 This is shown. On an upper part of the combustion chamber 25 is a spark plug 26 provided, which represents an ignition device. The spark plug26 ignites an air-fuel mixture in the combustion chamber 25 at a predetermined time based on a value from the ECU 3 output ignition signal.
[0014] The cylinder head 22 has an intake port 27a and an ejection port 27b on, which is connected to the combustion chamber 25 are connected. Furthermore, the cylinder head has 22 an intake valve 28a and an ejection valve 28b corresponding to the intake port 27a and the ejection port 27b open. The upper ends of the intake valve 28a and the ejection valve 28b feature an intake camshaft 29a and an exhaust camshaft 29b on.
[0015] On the crankshaft 20 The intake camshaft is located there. 29a , the exhaust camshaft 29b and a cam chain (not shown in the drawings). One rotation of the crankshaft.20 is connected to the intake camshaft 29a and the exhaust camshaft 29b transmitted via the camshaft. When the intake camshaft 29a and the exhaust camshaft 29b When rotated, the intake valve moves. 28a and the ejection valve 28b with reference to the combustion chamber 25 forwards and backwards at predetermined times.
[0016] An intake pipe 10 is connected to the upstream end of the intake port 27a connected via an intake manifold (not shown in the drawings). The passage in the intake pipe 10 and the intake port 27a represent an intake passage for intake air. At some parts of the intake pipe... 10 are an air purifier 11 , a throttle valve 12 and an expansion tank 13 Provided from the upstream side. On that part of the intake pipe. 10between the air purifier 11 and the throttle valve 12 is an air flow sensor 40 provided. The air volume sensor 40 measures the quantity (mass flow rate) of fluid in the intake manifold 10 through the air purifier 11 flowing intake air and sends the measured value to the ECU. 3 out of.
[0017] The throttle valve 12 It is configured to include, for example, a butterfly valve, and it is operated according to commands from the ECU. 3 opened and closed to adjust the flow rate of intake air (the amount of intake air) in the intake pipe 10 to flow. The expansion tank 13 compared to the intake pipe 10 It has a sufficiently large volume and serves to prevent the intake air from pulsating. (At the expansion tank) 13 is an intake air pressure sensor 41 provided. The intake air pressure sensor 41measures the pressure of the intake air (the intake air pressure) in the expansion tank 13 , and sends the measured value to the ECU 3 off. The ECU 3 The engine load can be estimated from the intake air volume and the aforementioned intake air pressure.
[0018] On the intake pipe 10 (or the intake port) 27a) , the (or the) on the downstream side of the expansion tank 13 is arranged, is an injector 14 , which is a fuel injection device, designed for injecting fuel. The injector 14 injects a predetermined amount of fuel into the intake manifold 10 (or the intake port) 27a) according to a command from the ECU 3 one. In other words, the engine 2 According to the present embodiment, it is configured with a so-called connection injection type engine.
[0019] With the downstream end of the discharge port 27b is an ejection pipe 15 connected via an exhaust manifold (not shown in the drawings). The exhaust port 27b and the passage in the intake pipe 10 represent an exhaust outlet. At a section of the exhaust pipe 15 is a catalytic converter 16 Intended for cleaning exhaust gas as part of an exhaust emission control device. The catalytic converter 16 It is configured with, for example, a three-way catalytic converter and converts pollutants (such as carbon monoxide, carbon hydride, nitrogen oxides, etc.) contained in exhaust gas into harmless substances (such as carbon dioxide, water, nitrogen, etc.). In the event that the engine 2 a diesel engine, such as the catalytic converter 16 , a catalytic oxidation converter can be used.
[0020] In a part of the downstream side of the catalytic converter 16 arranged ejection pipe 15 is a GPF 17 (Gasoline Particulate Filter) as a collection filter for collecting suspended particles (PM: "particulate matter"), such as those produced by combustion in the engine. 2 Produced soot, installed in front of and behind the GPF. 17 (on the upstream and downstream sides of the GPF) are temperature sensors 18a and 18b installed. The temperature sensors 18a and 18b measure the exhaust gas temperature before and after the GPF 17 and send the recorded values to the ECU 3 out of.
[0021] Furthermore, the GPF 17 a differential pressure sensor 19 installed. The differential pressure sensor 19 It measures the difference between the pressure before and after the GPF. 17and sends the measured value to the ECU 3 off. The ECU 3 Can the blockage condition of the GPF 17 , i.e., estimate the amount of collected PM from the pressure difference.
[0022] In the engine 2 , which is configured as described above, is a system powered by the air purifier 11 intake air flow rate setting of the throttle valve 12 exposed, and then flows into the intake port 27a through the expansion tank 13 At this point, fuel is injected by the injector. 14 injected at a predetermined time, thereby introducing the intake air and fuel into the intake port 27a The air-fuel mixture of the intake air and the fuel is mixed. It is then fed into the combustion chamber. 25 admitted at a time when the intake valve 28a is open, and it is in the combustion chamber 25compressed and then at a predetermined time by the spark plug 26 Ignited. The ignited and burned exhaust gas is expelled from the exhaust port. 27b through the ejection pipe 15 expelled to the outside. At this point, the exhaust gas passes through the catalytic converter. 16 cleaned, and PM is removed by the GPF 17 The exhaust noise is collected, and then the noise of the exhaust noise is dampened by a silencer (not shown in the drawings).
[0023] Furthermore, the engine contains 2 a water temperature sensor 42 for measuring engine water temperature and a crankshaft sensor 43 to detect the phase of the crankshaft 20 provided. The readings from the water temperature sensor. 42 and the crank sensor 43 will be sent to the ECU 3 Output from the crank sensor. 43 The engine speed can be calculated.
[0024] The vehicle also has a vehicle speed sensor. 44 A brake pedal is used to measure the vehicle speed. 45 and an accelerator pedal 46 provided. The measured value of the vehicle speed sensor. 44 will be sent to the ECU 3 The brake pedal was dispensed. 45 represents a braking device for generating a braking force in the vehicle and sends a predetermined electrical signal to the ECU according to the actuation quantity (actuation force) of the same. 3 Off. The accelerator pedal. 46 It represents an acceleration device for generating an acceleration force in the vehicle and sends a predetermined electrical signal to the ECU according to the actuation quantity (actuation force) of the same. 3 out of.
[0025] The ECU 3 It generally controls the operation of the entire vehicle, including various components besides the engine. 2The ECU 3 It is configured with a processor for performing various processes, memory, etc. The memory is configured with storage media, such as ROM (Read Only Memory), RAM (Random Access Memory), etc., according to its use. A control program for controlling the aforementioned components, etc., is stored in the memory.
[0026] For example, the ECU determines 3 The vehicle's status is determined from various sensors provided in the vehicle, and a control mechanism is used to activate the spark plug. 26 , of the injector 14 , of the throttle valve 12 etc. through the ECU 3 performs a filter regeneration facilitation control (described below) by the injector 14 and the spark plug 26 based on the temperature of the GPF 17The ECU controls the engine speed, engine load (intake air volume), etc., which are described in detail below. 3 stores a control mapping predefined based on engine speed and engine load (see Fig. 2) to perform the filter regeneration facilitation control, which is described in detail below. The ECU 3 Can GPF regeneration occur? 17 This facilitates fuel injection and ignition by controlling them based on the control mapping.
[0027] Furthermore, the exhaust emission control device is configured according to the present embodiment to control the engine 2 and its peripheral components (such as the catalytic converter) 16 , the GPF 17 , the ECU 3 and various sensors), which are described above.
[0028] Incidentally, diesel engine exhaust emission control systems use DPFs (Diesel Particulate Filters) as collection filters to gather PM (particulate matter) contained in the exhaust gas. A DPF can become clogged due to PM accumulation. Therefore, to clear the blockage, a filter regeneration process is initiated by raising the DPF's temperature to burn off the PM.
[0029] One such control system proposed is a post-injection system that supplies fuel to the exhaust side to facilitate PM combustion if PM accumulation in a DPF exceeds a predetermined level. However, this type of control system consumes additional fuel, as fuel is injected separately from the main injection solely for filter regeneration. This can therefore impact fuel efficiency. Furthermore, current stricter emissions regulations also require the installation of such particulate filters in gasoline engines.
[0030] For this reason, the inventor of this application, in view of the circumstances described above, has found that the exhaust emission control device is able to regenerate a collection filter in a suitable manner without affecting fuel efficiency, in the case that the collection filter is applied to a gasoline engine.
[0031] In particular, the ECU 3 In the present embodiment, the filter regeneration facilitation control is used to suspend fuel injection and / or ignition at a predetermined time interval within a regeneration facilitation range defined by engine speed and load. Here, the regeneration facilitation range represents a region in which the exhaust gas temperature is comparatively low and the engine 2It operates under a comparatively low load condition. Details of the regeneration facilitation range are described below. Furthermore, the filter regeneration facilitation control can also be referred to as the "interruption control" for interrupting fuel injection and / or ignition at a predetermined time interval.
[0032] According to this configuration, in a relatively stable operating condition during low-load operation (such as low-speed urban driving), if fuel injection and / or ignition is stopped (suspended) at the predetermined time interval, the temperatures of the components installed on the exhaust side, such as the catalytic converter, can be kept within a relatively stable operating condition during low-load operation (such as inner-city driving at low speed). 16 and the GPF 17 , increased so that the natural regeneration of the GPF 17 can be made easier.
[0033] If, for example, ignition is interrupted, an air-fuel mixture containing unburned fuel in the combustion chamber can be fed to the exhaust side, so that the fuel is ignited in the catalytic converter located on the downstream side. 16 It can be burned for expulsion. Therefore, the temperature of the GPF can be... 17 increase so that PM can be burned (eliminated), thereby regenerating the GPF. 17 This is facilitated. Furthermore, if fuel injection is suspended, only air can be supplied to the exhaust side, thus reducing the temperature of the GPF. 17 can increase.
[0034] Therefore, since it is not necessary, fuel can only be used for the regeneration of the GPF. 17 to inject the GPF 17 regenerate in a suitable manner without affecting fuel efficiency.
[0035] The tax representation according to the present exemplary embodiment is described below with reference to Fig. 2 described. Fig. 2 is a view that shows the tax mapping based on engine speed and engine load. Fig. Figure 2 shows the engine speed on a horizontal axis and the engine load on a vertical axis. Generally, engine speed and load increase when the vehicle speed increases due to accelerator pedal input. Conversely, engine speed and load decrease when the vehicle speed decreases due to deceleration.
[0036] As described above, the ECU stores 3 The control mapping, defined in advance based on engine speed and engine load, is used to perform the filter regeneration facilitation control. As in Fig. As shown in Figure 2, the control mapping is divided into a multitude of areas according to engine speed and engine load. In particular, in Fig. Two three areas are set up, and they are considered a first area. A1 , a second area A2 and a third area A3 sequentially from a range in which the engine speed and / or engine load is low. In particular, the first range A1 and the second area A2 also collectively referred to as a regeneration facilitation area R, and the third area A3 can also be described as a regeneration-facilitation-prevention area.
[0037] The regeneration facilitation area R represents an area in which the exhaust gas temperature is comparatively low, and the engine 2is operated in a comparatively low load condition, and it represents an area in which PM in the GPF 17 can accumulate. In other words, the regeneration facilitation area R can be an area in which active regeneration of the GPF is possible. 17 can be made easier.
[0038] From the regeneration facilitation area R, the first area can be A1 , in which the engine speed and engine load are low, a range in which PM in the GPF 17 likely to accumulate, and it represents an area in which active regeneration of the GPF is possible. 17 is required. As the first area A1 associated operating conditions of the engine 2 For example, an operating condition in which the engine is idling and an operating condition in which the vehicle is traveling at a comparatively low speed can be taken into account.
[0039] In the event that the operating condition of the engine 2 to the first area A1 belongs, holds the ECU 3 It only triggers an ignition at the predetermined time interval. Ignition is stopped, for example, for a specific cylinder within a cycle. However, the number of predetermined cylinders is not limited to one and can be two or more, or ignition can be stopped for all cylinders.
[0040] If ignition is interrupted, the air-fuel mixture (fuel) admitted to the combustion chamber flows to the exhaust side without being burned. This is because the air-fuel mixture is in the catalytic converter located on the downstream side. 16 When the fuel is burned for expulsion, the temperatures of the catalytic converter rise. 16and the GPF located on the downstream side of the catalytic converter 17 Therefore, PM can be in the GPF 17 are burned, thereby eliminating the PM, thus allowing regeneration of the GPF. 17 can be made easier.
[0041] The second area A2 , in which the engine speed and / or engine load is higher or greater than in the first range A1 This can be an area where the exhaust gas temperature is higher than in the first area. A1 is, but has not yet reached a sufficient temperature to activate the GPF 17 to regenerate, and it is an area where active regeneration of the GPF is possible. 17 is required. As an operating state of the engine. 2 , which belongs to the second area A2 For example, the case in which the vehicle is traveling at a speed higher than that in the first area can be taken into account.A1 is.
[0042] In the event that the operating condition of the engine 2 to the second area A2 belongs, holds the ECU 3 A fuel injection is initiated at the predetermined time interval. Similar to the ignition stop described above, a fuel injection stop is performed for, e.g., a predetermined cylinder within a cycle. In the second area A2 The exhaust gas temperature rises more than in the first area. A1 on, and the temperature of the GPF 17 It also increases more than in the first area. A1 to.
[0043] If fuel injection is stopped, only air is admitted to the combustion chamber, and exhaust gas at a comparatively high temperature flows to the exhaust side. Consequently, the temperature of the GPF located on the downstream side can 17increase in expulsion, so that regeneration of the GPF 17 can be facilitated. In other words, the second area A2 In contrast to the first area A1 a range in which the temperature of the GPF 17 Fuel consumption can increase simply by supplying air without adding fuel to the exhaust side. Therefore, stopping fuel injection can also improve fuel efficiency.
[0044] The third area A3 , in which the engine speed and / or engine load is higher or greater than in the first range A1 and the second A2 is a range in which the exhaust gas temperature is sufficiently high and the GPF 17 can regenerate naturally without facilitating active regeneration of the GPF. In other words, the third area A3is an area where regeneration of the GPF is not required 17 to facilitate (the regeneration-facilitation-prevention area). As a third area A3 associated operating state of the engine 2 For example, the case in which the vehicle suddenly accelerates and the case in which the vehicle is traveling at high speed can be taken into account.
[0045] In the event that the operating condition of the engine 2 to the third area A3 belongs, the ECU 3 The filter regeneration facilitation control described above does not execute, or forces the termination of, fuel injection and / or ignition. In other words, the ECU 3 It performs fuel injection and ignition based on a required torque according to an actuation of the accelerator pedal. 46proceed as usual. The reason for this, as described above, is that in the third area A3 It can be estimated that the temperature of the GPF 17 would be sufficiently high, even though GPF regeneration is necessary 17 is not made easier by stopping fuel injection or ignition.
[0046] As described above, in the present embodiment, regeneration of the GPF can be achieved by switching a control of the fuel injection or ignition based on the control mapping. 17 This will be made easier. Furthermore, the ECU controls 3 In the event that the filter regeneration facilitation control described above is carried out, the predetermined time interval is based on the temperature of the GPF. 17It controls the frequency of fuel injection and / or ignition interruptions based on engine speed and / or engine load. Details are described below.
[0047] The following describes a control flow according to the present embodiment with reference to Fig. 3 to Fig. 5 described. Fig. Figure 3 is a view that shows an example of a GPF regeneration control flow according to the present embodiment. Fig. Figure 4 is a view that shows an example of a filter regeneration facilitation determination flow according to the present embodiment. Fig. Figure 5 is a view that illustrates an example of a filter regeneration facilitation control flow according to the present embodiment. Furthermore, in the control flow described below, the operating object (calculation (data processing), determination, etc.) is the ECU unless explicitly stated otherwise.
[0048] As in Fig. 3 shown, determines the ECU 3 in STEP ST101 Whether the engine coolant temperature is equal to or higher than a predetermined temperature when the GPF regeneration control is initiated. The engine coolant temperature can be determined from the output of the coolant temperature sensor. 42 The temperature can be recorded. Furthermore, the predetermined temperature can be set to a temperature at which the engine begins to warm up. 2 has ended. In the event that the engine coolant temperature is equal to or higher than the predetermined temperature (“YES” in STEP 1) ST101 ), the ECU determines that the engine needs to warm up. 2 has been completed, and proceeds in the process from STEP ST102 continued. In the event that the engine coolant temperature does not reach the predetermined temperature (“NO” in STEP 1). ST101 ), the control process is terminated.
[0049] IN STEP ST102 The ECU 3the filter regeneration facilitation flow rate (see Fig. 4) through. The filter regeneration facilitation determination flow is a flow used to determine whether filter regeneration facilitation control is performed, and its details are described below. The ECU then proceeds to the process of STEP ST103 on.
[0050] IN STEP ST103 The ECU determines 3 Whether filter regeneration facilitation control is possible. In particular, the ECU determines 3 Whether a filter regeneration relief tax benefit approval flag is present. If the flag is present ("YES" in STEP ST103 ), the ECU determines that filter regeneration facilitation control is possible, and proceeds to the process of STEP ST104 continued. In the event that the flag is not present ("NO" in STEP 1). ST103 ), the ECU determines that filter regeneration facilitation control is not possible and terminates the control.
[0051] IN STEP ST104 The ECU determines 3 , whether the operating condition of the engine 2 to the area of regeneration facilitation R belongs. In the event that the operating condition of the engine 2 to the area of regeneration facilitation R belongs, i.e., in the event that the operating condition of the engine 2 to the first area A1 or the second A2 heard (“YES” in STEP) ST104 ), the ECU proceeds to the process of STEP ST105 continued. In the event that the operating condition of the engine 2 not to the area of regeneration facilitation R belongs, i.e., in the event that the operating condition of the engine 2 to the regeneration-facilitation-prevention area (the third area) A3) belongs (“NO” in STEP ST104 ), the control process is terminated.
[0052] IN STEP ST105 The ECU determines 3 Whether the vehicle speed is constant. The vehicle speed can be determined from the output of the vehicle speed sensor. 44 be recorded. In the event that the vehicle speed is constant ("YES" in STEP 1) ST105 ), the ECU proceeds to the process of STEP ST106 Continue. In case the vehicle speed is not constant ("NO" in STEP). ST105 ), the control is terminated. However, in STEP ST105 The determination is not limited to the case of determining whether the vehicle speed is constant, and it can be determined whether the vehicle speed is equal to or lower than a predetermined speed (e.g., whether the engine is running). 2 (runs empty).
[0053] IN STEP ST106 The ECU 3the filter regeneration facilitation control flow (see Fig. 5) through. Then the ECU proceeds to the process from STEP ST107 on.
[0054] IN STEP ST107 The ECU determines 3 Whether the filter regeneration facilitation control has ended. In particular, the ECU determines 3 Whether a filter regeneration relief control termination flag is present. If the flag is present ("YES" in STEP ST107 ), the ECU determines that the filter regeneration facilitation control has completed normally, and proceeds to the process of STEP ST108 continued. In the event that the flag is not present ("NO" in STEP 1). ST107 ), the ECU determines that the filter regeneration facilitation control has been forcibly terminated during this time, before the filter regeneration facilitation control is terminated, and proceeds to the process of STEP ST109 on.
[0055] IN STEP ST108 The ECU 3 It sets an initial prevent time to prevent fuel injection and ignition from stopping and starts counting down this initial prevent time. From this moment on, the ECU prevents 3 A halt to fuel injection and ignition until the counting is complete. In other words, the ECU 3 The filter regeneration relief control prevents the filter regeneration for the first prevention period. Then the control is deactivated.
[0056] IN STEP ST109 The ECU 3 A second prevention time, shorter than the first, is entered, and a countdown of the second prevention time begins. From this moment on, the ECU prevents 3 A halt to fuel injection and ignition until the counting is complete. In other words, the ECU 3The filter regeneration facilitation control prevents the second prevention period. Then the control is terminated.
[0057] In the present embodiment, the ECU determines in particular whether the filter regeneration facilitation control is activated in STEP ST107 has ended, and sets a subsequent prevention time (STEP ST108 or ST109 In the event that the filter regeneration facilitation control has ended normally, the ECU determines that the GPF temperature 17 has increased sufficiently, and sets the first prevention time, thereby preventing the GPF from 17 overheated by re-executing the filter regeneration relief control.
[0058] Meanwhile, in the event that the control was forcibly terminated during this time because the condition was not met, it can be estimated that the temperature of the GPF17 would decrease. For this reason, the ECU sets the second prevention time shorter than the first prevention time. Consequently, the filter regeneration facilitation control can be performed again sooner, and the GPF temperature can be prevented from rising. 17 decreases.
[0059] The following describes the filter regeneration facilitation determination flow. The corresponding determination flow corresponds to the process of STEP ST102 from Fig. 3. As in Fig. 4 shown, if the determination in STEP ST201 The ECU determines when it starts. 3 , whether the operating condition of the engine 2 to the third area A3 belongs. In the event that the operating condition of the engine 2 to the third area A3 heard (“YES” in STEP) ST201 ), the ECU proceeds to the process of STEP ST202 continued. In the event that the operating condition of the engine 2 not to the third area A3 heard (“NO” in STEP) ST201 ), the ECU proceeds to the process of STEP ST203 on.
[0060] IN STEP ST202 The ECU determines 3 , preventing the corresponding control without setting the filter regeneration relief control performance approval flag, ends the determination, and proceeds to the process of STEP ST103 from Fig. 3 continued.
[0061] IN STEP ST203 The ECU determines 3 , whether a cooling period is required after high-load operation of the engine 2 has expired. It is taken into account that immediately after the engine 2 has transitioned from high-load operation to low-load operation, i.e., immediately after a transition from the third range A3 in the first area A1 or the second area A2, the GPF 17 would be in a comparatively high temperature state. For this reason, a cooling period is set so that the filter regeneration facilitation control is carried out after the GPF temperature has cooled down. 17 has been stabilized. Consequently, tax hunting and GPF overheating are possible. 17 can be prevented. However, the STEP is ST203 not limited to cooling time, and the determination can be based on the temperature of the GPF 17 be performed.
[0062] In case the cooling time has not expired (“NO” in STEP ST203 ), the ECU proceeds to the process of STEP ST202 Continue. In case the cooling time has expired (“YES” in STEP 1). ST203 ), the ECU proceeds to the process of STEP ST204 continued. However, the cooling time may vary depending on the engine's operating condition. 2 be modified appropriately.
[0063] IN STEP ST204 The ECU determines 3 , whether the predetermined prevention time has expired. The predetermined prevention time is the first prevention time or the second prevention time described above. In the event that the predetermined prevention time has not expired (“NO” in STEP 1) ST204 ), the ECU proceeds to the process of STEP ST202 continued. In the event that the predetermined prevention time has expired ("YES" in STEP 1) ST204 ), the ECU proceeds to the process of STEP ST205 on.
[0064] IN STEP ST205 sets the ECU 3 The filter regeneration relief tax performance approval flag ends the determination and proceeds to the process of STEP ST103 from Fig. 3 continued.
[0065] The following describes the filter regeneration facilitation control flow. The corresponding control flow corresponds to the process of STEP ST106 from Fig. 3. As in Fig. 5 shown, if the control is in STEP ST301 Once started, the ECU 3 a condition to stop fuel injection or ignition.
[0066] Here, the stop condition is a stop time interval and the frequency of stops. The stop time interval can be based on the temperature of the GPF. 17 can be configured. For example, the ECU can be adjusted. 3 shorten the stop time interval if the temperature of the GPF 17 decreases. By shortening the stop time interval, the GPF can be reduced. 17 be raised early. In the event that the GPF temperature 17 By extending the holding time interval, the temperature of the GPF can be increased relatively quickly. 17will be increased gradually.
[0067] Furthermore, if the hold time interval is set, the rate of temperature increase of the GPF can be adjusted. 17 This must be taken into account relative to time. Especially in the case of a change in the GPF temperature. 17 equal to or higher than a predetermined temperature (one in Fig. 6 shown temperature D1 ) is, which is lower than a setpoint temperature (one in Fig. 6 shown temperature D2 ) is, and the rate of temperature increase relative to time is equal to or greater than a predetermined value, the ECU extends 3 The holding time interval. By increasing the holding time interval, the rate of temperature increase can be reduced, thus slowing the rise in GPF temperature. 17 This can happen gradually. Therefore, overheating of the GPF is possible. 17This can be prevented. Furthermore, examples of how the stop time interval can be set include the time interval corresponding to one ignition time, the time interval corresponding to two ignition times, etc., and the stop time interval can be set in one cycle unit.
[0068] Furthermore, the frequency of stops can be adjusted based on engine speed and / or engine load. For example, the ECU increases 3 The frequency of fuel injection or ignition when engine speed and / or engine load decreases. In the event that engine speed and / or engine load is low, because the temperature of the GPF can be estimated 17 If the temperature would be low, the frequency of stops is increased to such an extent that the temperature of the GPF rises. 17 can be facilitated in a suitable manner.
[0069] However, a combination of stop time interval and stop frequency settings can be used to implement the control. If a stop condition is set considering its impact on drivability, the control can be adjusted to account for the rise in GPF temperature. 17 be implemented in a suitable manner.
[0070] After setting the stop condition, the ECU proceeds to the process of STEP ST302 Onwards. In STEP ST302 The ECU determines 3 , whether the vehicle speed is constant. If the vehicle speed is constant ("YES" in STEP 1) ST302 ), the ECU proceeds to the process of STEP ST303 Continue. In case the vehicle speed is not constant ("NO" in STEP). ST302 ), the ECU proceeds to the process of STEP ST307 gone. However, in STEP ST302 A determination is not limited to the case of determining whether the vehicle speed is constant, and it can be determined whether the vehicle speed is equal to or lower than a predetermined speed.
[0071] IN STEP ST303 The ECU 3 This results in the interruption of fuel injection and / or ignition. Furthermore, the ECU... 3 the opening degree of the throttle valve 12 One. This serves to supplement or support the torque, which can be reduced due to stopping. Here, the opening degree of the throttle valve can be adjusted. 12The throttle opening is set to the sum of the normal throttle opening, the opening for correction following a stop, and the opening for feedback correction based on a change in actual torque. As described above, a decrease in torque is predicted if a stop is performed. Therefore, in anticipation of the torque decrease, the throttle opening is adjusted (increased) to increase the intake air volume. Consequently, any change in torque attributable to stopping can be minimized.
[0072] Then the ECU proceeds to the process of STEP ST304 Onwards. In STEP ST304 increases the ECU 3 The frequency of a stop changes from n to (n+1). Then the ECU drives 3 to the process of STEP ST305 on.
[0073] IN STEP ST305 The ECU determines 3, whether the frequency of a stop has reached a predetermined frequency. If the frequency of a stop has reached the predetermined frequency ("YES" in STEP). ST305 ), the ECU proceeds to the process of STEP ST306 continued. In the event that the frequency of a stop has not reached the predetermined frequency ("NO" in STEP). ST305 ), the ECU returns to the process from STEP ST302 back.
[0074] IN STEP ST306 sets the ECU 3 A control termination flag indicates that the filter regeneration facilitation control has ended. The ECU then drives 3 to the process of STEP ST307 on.
[0075] IN STEP ST307 The ECU 3 The throttle opening degree returns to its normal opening degree and the filter regeneration facilitation control ends. The ECU then proceeds to the process of STEP ST107 from Fig. 3 continued.
[0076] The following refers to Fig. 6 a change in the GPF temperature (exhaust gas temperature) over time is described for the case that the control (GPF regeneration control) is applied according to the present embodiment. Fig. Figure 6 is a time graph showing a change in the GPF temperature (exhaust gas temperature) over time according to the present embodiment.
[0077] As in Fig. Shown in section 6, the temperature of the GPF 17 gradually, in case the temperature of the GPF 17 a comparatively low temperature D0 This is the case if the filter regeneration facilitation control is activated at a predetermined time. T1 has been started. After T1 The stopping condition will be changed if the temperature of the GPF 17 the predetermined temperature D1 at a time T2This is achieved. For example, the holding time interval is extended. Consequently, the rate of temperature increase of the GPF decreases. 17 The temperature drops after T2, resulting in a gradual increase. After that, the temperature of the GPF reaches... 17 at a time T3 the target temperature D2 Then the temperature of the GPF will be 17 The system remains at D2 until the filter regeneration relief control is complete. This prevents the GPF from overheating. 17 prevented. Afterwards, if the filter regeneration facilitation control is activated at any time... T4 is finished, PM in the GPF 17 eliminated in a suitable manner. At this point, the predetermined prevention time (the first prevention time) is set. Therefore, the temperature of the GPF 17 after the time T4 gradually reduced.
[0078] As described above, in the present embodiment, in the regeneration facilitation range of the control mapping defined on the basis of the engine speed and engine load, the filter regeneration facilitation control is carried out to stop the fuel injection and / or ignition at the predetermined time interval in such a way that the GPF 17 can be regenerated in a suitable manner without affecting fuel efficiency. This is particularly important because natural regeneration of the GPF is possible. 17 Since this can be facilitated by simply stopping fuel injection or ignition, it is not necessary to address the accumulation of PM in the GPF. 17 to monitor, and the control can be simplified.
[0079] Furthermore, in the embodiment described above, the description uses the connection injection type motor. 2This has been done as an example. However, the present invention is not limited to this configuration. For example, a direct injection engine can be used. 2 be used.
[0080] Furthermore, the embodiment described above uses a gasoline engine as an example; however, the present invention is not limited to this. The present control system can also be applied to diesel engines.
[0081] Furthermore, the embodiment described above uses the DOHC engine as an example; however, the present invention is not limited to this. The engine 2 It could be a SOHC engine (“Single Overhead Camshaft”; simply an overhead camshaft).
[0082] Furthermore, the embodiment described above describes a case where the regeneration facilitation area is divided into two areas; however, the present invention is not limited to this. The regeneration facilitation area R can consist of one area, or it can be divided into three or more areas.
[0083] Furthermore, the embodiment described above describes the case where the boundary lines defining the individual areas in the control diagram are shown as curves; however, the present invention is not limited to this. The boundary lines can be modified in a suitable manner and can, for example, be straight lines.
[0084] Furthermore, although the exemplary embodiment and the modifications have been described, other embodiments of the present invention can be combinations of all or some components of the exemplary embodiment and the modifications.
[0085] Furthermore, the embodiment of the present invention is not limited to the embodiment described above, and various changes, substitutions, and modifications can be made without departing from the essence of the technical idea of the present invention. Moreover, if the technical idea of the present invention can be realized in a different way due to technological advances or by means of a derived technology, the present invention can be implemented in different ways. Accordingly, the claims cover all embodiments that may fall within the scope of the technical idea of the present invention.
[0086] As described above, the present invention has the effect that a collection filter for collecting suspended particles can be regenerated in a suitable manner without affecting fuel efficiency, and it is particularly useful in exhaust emission control devices. QUOTES INCLUDED IN THE DESCRIPTION
[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature
[0000] JP 2004190641 A
[0004]
Claims
[1] Exhaust emission control device comprising: a collection filter configured to collect soot emitted from an engine; and a control device configured to control a fuel injection device and an ignition device, wherein the control device performs a filter regeneration facilitation control to halt fuel injection and / or ignition at a predetermined time interval within a regeneration facilitation range of a control mapping defined on the basis of an engine speed and an engine load. [2] Exhaust emission control device according to claim 1, where the regeneration facilitation area includes a first area, and the control device merely stops the ignition for the predetermined time interval in the first area. [3] Exhaust emission control device according to claim 2, wherein the regeneration facilitation range further includes a second range in which the engine speed and / or engine load is higher or greater than in the first range, and the control device stops the fuel injection at the predetermined time interval in the second area. [4] Exhaust emission control device according to one of claims 1 to 3, wherein the control device does not perform or forcibly terminates the filter regeneration facilitation control in a regeneration facilitation prevention range in which the engine speed and / or the engine load is higher or greater than that in the regeneration facilitation range. [5] Exhaust emission control device according to claim 4, wherein in the event that the filter regeneration facilitation control is completed, the control device sets a first prevention time to prevent the fuel injection and ignition from stopping. [6] Exhaust emission control device according to claim 5, wherein in the event that the filter regeneration facilitation control is forcibly terminated before the filter regeneration facilitation control has ended, the control device sets a second prevention time which is shorter than the first prevention time and prevents the fuel injection and ignition from being stopped for the second prevention time. [7] Exhaust emission control device according to one of claims 1 to 6, wherein in the event that the filter regeneration facilitation control is carried out, the control device controls the predetermined time interval on the basis of a temperature of the collection filter. [8] Exhaust emission control device according to claim 7, wherein in the event that the temperature of the collection filter is equal to or higher than a predetermined temperature which is lower than a setpoint temperature, and the rate of increase of the temperature relative to time is equal to or greater than a predetermined rate, the control device extends the predetermined time interval. [9] Exhaust emission control device according to any one of claims 1 to 8, wherein, in the event that filter regeneration facilitation control is performed, the control device increases the frequency of stopping fuel injection or ignition when the engine speed and / or engine load decreases. [10] Exhaust emission control device according to one of claims 1 to 9, wherein in the event that the filter regeneration facilitation control is carried out, the control device increases an intake air quantity.