JP2008215535A - Controller of diesel vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a controller of a diesel vehicle capable of securing sufficient traveling performance by preventing an operating range in which a shift-up is disabled from occurring while preventing trouble from occurring by limiting the maximum output of an engine when a filter excessively collects dust and dirt. <P>SOLUTION: This controller of a diesel engine comprises an engine ECC as a filter regenerating means and an output limiting means for limiting the maximum output of the engine, an accelerator opening sensor for detecting an accelerator opening, a vehicle speed sensor for detecting a vehicle speed, a gear shift diagram storage means for storing a gear shift diagram, a gear shift indicating means for selectively indicating the accelerator opening according to the gear shift diagram and the shift stage of a transmission according to the vehicle speed, and a transmission ECC as a shift condition selector means for so changing up-shift lines Lu1, Lu2, Lu3, Lu4 in the shift diagram M as to more up-shift on the low vehicle speed side when the accelerator opening is larger than a predetermined opening and the maximum output of the engine is limited than when the maximum output of the engine is not limited. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a control device for a diesel vehicle in which a DPF (Diesel Particulate Filter) device is mounted, and regeneration control of the DPF device and engine output restriction are performed when the DPF device accumulates soot.

  Recently, a car equipped with a diesel engine (hereinafter referred to as a diesel car) equipped with a DPF device that collects particulate matter (particulate matter; hereinafter also referred to as PM) such as carbon particles in the exhaust gas. It has been known.

  In this type of conventional diesel vehicle, although the particulate matter purification rate by the DPF device is high, the particulate matter accumulates in the DPF device and becomes soot-like, and if the exhaust gas flow resistance in the exhaust pipe increases, the exhaust pressure (Engine back pressure) will increase. Therefore, control is performed such that soot accumulated in the DPF device is combusted by so-called post-injection, or engine output is limited (see, for example, Patent Document 1).

Also, the pressure difference before and after the DPF device is detected by a sensor, the amount of particulate matter accumulated is estimated based on the pressure difference information, the regeneration processing time is managed, and post-injection without waste is performed ( For example, refer to Patent Document 2), or the possibility of post-injection is determined based on the main injection amount and the upper limit injection amount when the differential pressure sensor is abnormal, and the regeneration process can be performed even when the differential pressure sensor is abnormal (For example, refer to Patent Document 3) or an exhaust bypass passage with a valve that bypasses the DPF device in order to prevent an excessive increase in exhaust pressure when particulate matter is excessively collected in the DPF device (for example, Patent Document 4) is known. Furthermore, there is also known a method in which the collection amount is calculated based on the exhaust gas temperature and the engine speed for sensor abnormality separately from the collection amount calculation based on the differential pressure across the normal DPF device ( For example, see Patent Document 5).
JP 2005-113752 A JP-A-2005-291036 JP 2006-9598 A JP-A-5-332126 JP 7-317529 A

  However, in the control device for a diesel vehicle as described above, if any abnormality occurs in the DPF device, the upstream oxidation catalyst, the fuel injection system that performs post-injection, or the like, and the stable regeneration process cannot be performed, the DPF device The filter becomes over trapped and soot accumulates in the DPF device. The increase in the exhaust pressure especially at high output makes the DPF device, the exhaust system seal, the turbocharger, etc. easily damaged. There is a problem that leads to expansion of parts.

  Also, when limiting the maximum output of a diesel engine to suppress an increase in exhaust pressure, in an automatic transmission in which shift conditions are set to upshift near the maximum output when the engine is normal, the accelerator opening is When it is large, the engine speed does not increase as normal due to the limitation of the maximum output, so a sufficient increase in vehicle speed cannot be obtained, and there is an operating range in which upshifting to the next gear stage to be selected is not possible and sufficient There arises a problem that traveling performance cannot be secured.

  Therefore, the present invention reliably prevents the occurrence of an operation region in which upshifting cannot be performed while restricting the maximum output of the engine when the filter is excessively collected to prevent failure, and ensures sufficient traveling performance. An object of the present invention is to provide a control device for a diesel vehicle that can be used.

  In order to achieve the above object, the diesel vehicle control device of the present invention is (1) a diesel vehicle control device equipped with an engine and a transmission, and a filter for collecting particulate matter in the exhaust gas of the engine. Regeneration processing means for executing regeneration processing of the filter when the particulate matter is deposited on the filter, output limiting means for restricting the maximum output of the engine when the particulate matter is deposited on the filter in a predetermined amount or more, and An accelerator opening detecting means for detecting the accelerator opening of the vehicle, a vehicle speed detecting means for detecting the vehicle speed of the vehicle, and a shift diagram defining a gear position of the transmission according to the accelerator opening and the vehicle speed; A shift diagram storing means for storing; a shift instruction means for selecting and instructing a gear position of the transmission according to the accelerator opening and the vehicle speed according to the shift diagram; In the shift diagram, when the cell opening is larger than a predetermined opening and the maximum output of the engine is limited, the upshift is performed on the low vehicle speed side compared to the case where the maximum output of the engine is not limited. Shift condition switching means for changing the upshift line is provided.

  With this configuration, the maximum output of the engine is limited by the output limiting means when the particulate matter is accumulated on the filter in a predetermined amount or more by the filter regeneration process. When the accelerator opening is larger than the predetermined opening and the maximum output of the engine is limited, the shift diagram is changed so that the upshift is performed on the low vehicle speed side as compared with the case where the maximum output of the engine is not limited. The upshift line is changed. Therefore, although the accelerator opening is large, the engine speed has not been increased as normal due to the limitation of the maximum engine output, and even when the vehicle speed cannot be increased sufficiently, it has been changed to upshift at a lower vehicle speed than usual. When the vehicle speed increases across the shift line or the accelerator opening increases, an upshift to the next gear stage is performed, so that sufficient traveling performance is ensured and fuel efficiency is also improved.

  In the control apparatus for a diesel vehicle of the present invention having the above-described configuration, (2) the shift condition switching means moves to the low vehicle speed side of the upshift line according to the limit amount of the maximum output of the engine by the output limiting means. It is preferable to determine the amount of change.

  In this case, the upshift is performed at an accurate timing according to the maximum output limit amount of the engine.

  The control device for a diesel vehicle having the configuration of (1) or (2) includes (3) a travel load detection unit that detects a travel load of the vehicle, the accelerator opening is larger than a predetermined opening, and When the maximum output of the engine is limited and the vehicle driving load is greater than a predetermined value, the low vehicle speed of the upshift line by the shift condition switching unit is determined based on the detection information of the driving load detection unit. It is preferable that the change to the side is prohibited.

  In this case, an upshift that causes a torque shortage and a decrease in vehicle speed when the traveling load is large is avoided, and stable traveling performance is ensured.

  The control device for a diesel vehicle having the configuration of any one of the above (1) to (3), (4) when the accelerator opening is larger than a predetermined opening and the maximum output of the engine is limited, The shift condition switching means downshifts the corresponding downshift line in the shift diagram on the low vehicle speed side compared to the other cases, according to the amount of change of the upshift line to the low vehicle speed side. It should be changed.

  In this case, according to the amount of change of the upshift line to the low vehicle speed side in the high accelerator opening range, the corresponding downshift line is changed to the low vehicle speed side, and stable driving performance that suppresses the occurrence of hunting Will be secured.

  The control device for a diesel vehicle having the configuration of any one of the above (1) to (4) includes: (5) an automatic transmission in which the transmission can automatically shift to a shift stage selected and instructed by the shift instruction means. It is preferable that it is comprised.

  With this configuration, it is possible to reliably prevent an operation region in which upshifting cannot be performed by the automatic transmission and to ensure sufficient traveling performance.

  The control device for a diesel vehicle having the configuration of any one of the above (1) to (4) includes: (6) a shift indicator in which the transmission is configured by a manual transmission and the shift instruction unit displays an upshift timing. It may be constituted by.

  In this case, while restricting the maximum output of the engine at the time of excessive collection of the filter to prevent parts failure, it prevents the occurrence of a driving area that cannot be upshifted with a normal operating feeling, and provides sufficient driving performance and speed change operation fee. A ring can be secured.

  According to the present invention, even when the accelerator opening is large, the engine speed is not increased as usual due to the limitation of the maximum engine output, and even when the vehicle speed cannot be sufficiently increased, the upshift is performed on the lower vehicle speed side than usual. Since the upshift to the next gear stage is performed when the vehicle speed rises or the accelerator opening increases across the changed upshift line, the engine's maximum output is limited when the filter is over-collected to prevent component failure. While being prevented, it is possible to provide a control device for a diesel vehicle that can reliably prevent an operation region that cannot be upshifted and can ensure sufficient traveling performance.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.

  1 to 6 are diagrams showing an embodiment of a control apparatus for a diesel vehicle according to the present invention.

  First, the configuration will be described. In FIG. 1, an engine 10 configured as a multi-cylinder diesel engine has a plurality of cylinders 11 (only one cylinder is shown in FIG. 1). The engine 10 includes a fuel injection valve 12 that injects fuel into a combustion chamber 13 in each cylinder 11, an exhaust device 14 that exhausts exhaust gas from the combustion chamber 13, and air that uses exhaust energy in the exhaust device 14. And a glow plug 17 for assisting in starting by red heat by energization at the time of cold starting or the like.

  The fuel injection valve 12 introduces fuel (for example, light oil) pressurized to a high fuel pressure (fuel pressure) by a supply pump (not shown), and the fuel is an engine control computer (electronic control unit; hereinafter referred to as engine ECC). ) The fuel is injected into the combustion chamber 13 in response to an injection command signal from 30. The fuel injection valve 12 is constituted by a known needle valve that is electromagnetically driven, and the ratio (duty ratio) of the valve opening time during the predetermined time is controlled in accordance with a pulse-like injection command signal every predetermined time. Thus, fuel can be injected at a timing and an opening degree corresponding to the injection command signal.

  The intake system that sucks air into the combustion chamber 13 is not shown in detail, but the intake manifold, an air cleaner that cleans the intake air with a filter upstream thereof, and supercharging downstream of the supercharger 15 An intercooler that cools the intake air whose temperature has been increased, an air flow meter that detects the intake air amount (intake air amount), and a throttle valve that adjusts the intake air amount into the engine 10 are provided. These configurations are the same as known ones, and the throttle valve is, for example, an electronically controlled type whose throttle opening can be adjusted steplessly by an actuator unit (not shown).

  The supercharger 15 has an intake air compressor 15a and an exhaust turbine 15b that are integrally connected to each other in the rotational direction, and is a known one that rotates the intake air compressor 15a by rotating the exhaust turbine 15b with exhaust energy. Positive pressure air can be inhaled.

  On the other hand, the exhaust device 14 includes an exhaust manifold 21 mounted on the exhaust port side of the engine 10, an exhaust pipe 22 downstream thereof, and an oxidation catalyst 23 mounted on the exhaust pipe 22 downstream of the supercharger 15. A post-injection fuel injection valve 19 disposed in the exhaust pipe upstream of the supercharger 15, a DPF device 25 attached to the exhaust pipe 22 downstream of the oxidation catalyst 23, and the oxidation catalyst 23 Exhaust temperature sensors 26a and 26b arranged on the front and rear sides (both ends), a DPF upstream side exhaust pressure sensor 27 positioned between the oxidation catalyst 23 and the DPF device 25, and a differential pressure for detecting a differential pressure across the DPF device 25 Sensor 28.

  The fuel injection valve 19 for post-injection injects part of the fuel pumped up by a supply pump (not shown) into the exhaust manifold 21 in addition to the fuel injection valve 12, and the fuel is applied at a fuel pressure of a predetermined pressure or higher. When opened, the fuel can be injected into the exhaust manifold 21 to be vaporized, thereby promoting the combustion of particulate matter accumulated in the DPF device 25.

The oxidation catalyst 23 adjusts, for example, the oxygen concentration in the exhaust gas and the unburned component (HC) as appropriate, thereby reducing NOx in the exhaust gas to NO ₂ and NO and reacting it with HC and CO in the exhaust gas to form N _2. Alternatively, HC or CO can be oxidized to H ₂ O or CO _2, and the fuel that is post-injected and vaporized from the fuel injection valve 19 for post-injection is also used for that purpose.

  The DPF device 25, as a filter (not shown in detail) for collecting particulate matter in the exhaust gas of the engine 10, achieves both a high collection rate for particulate matter and a low pressure loss in the exhaust pipe. Therefore, for example, a monolithic structure is adopted, and the pore size and distribution of the filter are optimized, and the exhaust purification ability can be further enhanced in combination with the oxidation catalyst 23.

  Although not shown, an exhaust passage having a waste gate valve function on the exhaust turbine 15b side of the supercharger 15 and bypassing the exhaust turbine 15b can be formed according to the opening degree. Further, an exhaust gas recirculation (hereinafter referred to as EGR) passage for exhaust gas recirculation (hereinafter referred to as EGR) that bypasses the combustion chamber in the engine 10 to connect the exhaust passage in the exhaust manifold 21 and the intake passage in the intake manifold, and the exhaust gas recirculation amount by the EGR passage. And an EGR cooler for cooling the exhaust gas recirculated through the EGR passage.

  On the other hand, the energization control to the supply pump and the fuel injection amount control by the fuel injection valves 12 and 19 are electronically controlled by the engine ECC 30, and the engine ECC 30 executes a predetermined control program every predetermined time. Is configured to run.

  The engine ECC 30 does not show a detailed hardware configuration, but a backup memory such as a central processing unit (CPU), a read only memory (ROM), a random access memory (RAM), and an electronically erasable and programmable read only memory (EEPROM). , An input interface circuit including an A / D converter, a buffer, and the like, and an output interface circuit including a drive circuit and the like.

  In addition to the exhaust temperature sensors 26a and 26b, the DPF upstream side exhaust pressure sensor 27, and the differential pressure sensor 28, the input interface circuit of the engine ECC 30 includes an accelerator opening sensor 41 (accelerator opening sensor) that detects the amount of depression of an accelerator pedal (not shown). Degree detecting means), a vehicle speed sensor 42 (vehicle speed detecting means) for detecting the traveling speed or wheel rotational speed of the vehicle on which the engine 10 is mounted, and a crank for outputting a signal corresponding to the engine speed from the crank rotation in a predetermined angle unit. An angle sensor 43 (rotational speed sensor) is connected to each other, and further, an air flow meter (not shown), a throttle opening sensor, an intake pipe pressure sensor that detects intake pressure (supercharging pressure) of the engine 10, and the like are connected to each other. Detection information from the sensor group is taken into the engine ECC 30.

  The acceleration request amount detected by the accelerator opening sensor 41 may be detected as a change (increase) amount of the throttle opening detected by the throttle opening sensor. The air flow meter, throttle opening sensor, crank angle sensor, vehicle speed sensor, intake pipe pressure sensor, and the like are means for detecting the operating state of the engine 10.

  The supply pump and the fuel injection valves 12 and 19 are connected to the output interface circuit of the engine ECC 30 via respective drive circuits (not shown).

In the ROM of the engine ECC 30, for example, a calculation formula for obtaining the amount of particulate matter deposited on the filter of the DPF device 25 based on the differential pressure level detected by the differential pressure sensor 28 (for example, paragraph 0073 of Patent Document 1 above) Where PMf = (1 / C1) (ΔP / (μ · Q ^α )) − a; where ΔP is the filter differential pressure, C1, α, a are constants obtained through experiments, and μ is the exhaust gas temperature. Viscosity coefficient obtained as a function f (T), Q is the exhaust gas flow rate) or map (showing a correlation in which the deposition amount increases as the differential pressure increases), and particulate matter is deposited on the filter of the DPF device 25 A regeneration processing program for executing the post-injection by the fuel injection valve 19 for post-injection for a time corresponding to the amount of accumulation and executing the regeneration processing of the filter is stored. And functions as the reproduction processing means for cooperation with the fuel injection valve 19 for injection to executing the regeneration process of the filter.

  When the particulate matter accumulates in the filter of the DPF device 25 in the ROM of the engine ECC 30 on the filter of the DPF device 25 based on the detection information of the exhaust temperature sensors 26a and 26b, the DPF upstream exhaust pressure sensor 27, and the differential pressure sensor 28. A known output restriction program for selectively restricting the maximum output of the engine 10 is stored, and the engine ECC 30 restricts the maximum output of the engine 10 when particulate matter is accumulated in a predetermined amount or more on the filter. Also works. The maximum output limit here is, for example, set so that the maximum value of the accelerator opening is set smaller than normal, and the maximum throttle opening normally obtained with respect to the maximum depression amount of the accelerator pedal is not obtained. It is to be.

  When the engine ECC 30 executes the output restriction program, its output restriction width (for example, the restriction amount (%) from the maximum accelerator opening, the upper limit engine speed (rpm), the injection amount reduction ratio, etc.), the differential pressure sensor 28 Information on the differential pressure across the DPF (instantaneous value for each calculation cycle), accelerator opening, vehicle speed, and other information, which is detected information, is transmitted to an automatic transmission control computer (hereinafter referred to as automatic transmission ECC) 40 as control information and output. The engine ECC 30 is equipped with a control program and a communication IC for that purpose.

  The automatic transmission ECC 40 is a means for performing automatic shift control for the known automatic transmission 60, and includes a CPU, ROM, RAM, backup memory, input interface circuit, and output interface circuit in substantially the same manner as the engine ECC 30. It is configured to include. In the ROM of the automatic transmission ECC 40, a shift diagram that defines the gear position of the automatic transmission 60 according to the accelerator opening and the vehicle speed, which are control information from the engine ECC 30, is stored together with the automatic transmission control program. Yes. That is, the ROM of the automatic transmission ECC 40 is a shift diagram storing means, and the automatic transmission ECC 40 has an accelerator opening detected by the accelerator opening sensor 41, a vehicle speed detected by the vehicle speed sensor 42, and a crank. Shift instruction means for selecting and instructing the gear position of the automatic transmission 60 according to the accelerator opening and the vehicle speed according to the shift diagram M based on detection information such as the engine speed detected based on the sensor information of the angle sensor 43. It has become.

  Specifically, as shown in FIG. 2, the shift diagram M stored in the ROM of the automatic transmission ECC 40 is a diagram representing the entire traveling state with the accelerator opening as the vertical axis and the vehicle speed as the horizontal axis. A plurality of upshift lines Lu1, Lu2, Lu3, and Lu4 representing upshift timing (shown by solid lines in the figure), and a plurality of downshift lines Ld1, Ld2, Ld3, and Ld4 representing downshift timing, Each is set according to the maximum output in the normal output range of the engine 10 in advance. For example, when the vehicle speed reaches the upshift line Lu1 after traveling at the first speed, it is upshifted to the second speed and further travels at the second speed. When the vehicle speed reaches the upshift line Lu2, the shift control is performed such as upshifting to the third speed. Such shift lines and normal shift control based on them are the same as those known.

  The automatic transmission ECC 40 according to the present embodiment further cooperates with the engine ECC 30 when the accelerator opening is larger than the predetermined opening and the maximum output of the engine 10 is restricted. The upshift lines Lu1, Lu2, Lu3, and Lu4 in the shift diagram M are changed upshift lines shown in FIG. It has a function of shift condition switching means for changing to Lc1, Lc2, Lc3, and Lc4, and a control program for that is stored in the ROM of the engine ECC 30 and the automatic transmission ECC 40.

  As shown by upshift lines Lu1, Lu2, Lu3, and Lu4 in FIG. 2, in normal control, when traveling at the first speed with the maximum output of the accelerator opening 100 [%], it is upshifted to the second speed at about 37 km / h. However, if normal control is performed during the 1st-speed driving at the maximum output, if the maximum output is limited so that the engine speed reaches 5200 rpm but only reaches about 4000 rpm, the engine ECC 30 Information indicating the degree (limit width) is sent to the automatic transmission ECC 40, and the automatic transmission ECC 40 as the shift condition switching means changes the upshift line according to the limit amount of the maximum output of the engine 10 by the engine ECC 30 as the output limiting means. The amount of change of Lu1, Lu2, Lu3 and Lu4 to the low vehicle speed side (changed upshift lines Lc1, Lc2, It is adapted to determine the vehicle speed change amount) to c3 and Lc4.

  The ROM of the automatic transmission ECC 40 also has a program for exerting a function as a traveling load detection means for detecting the current traveling load of the vehicle based on the accelerator opening and the vehicle speed, and the accelerator opening is greater than the predetermined opening. When the maximum output of the engine 10 is limited and the vehicle traveling load is greater than a predetermined value, the upshift line Lu1, by the shift condition switching unit, based on the detection information as the traveling load detection unit, Changes to Lu2, Lu3, and Lu4 to the low vehicle speed side (changes to changed upshift lines Lc1 to Lc4) are prohibited.

  Further, the automatic transmission ECC 40 serving as a shift condition switching means reduces the upshift lines Lu1, Lu2, Lu3, and Lu4 when the accelerator opening is larger than a predetermined opening and the maximum output of the engine 10 is limited. In accordance with the amount of change to the vehicle speed side, the corresponding downshift lines Ld1, Ld2, Ld3 and Ld4 in the shift diagram M are changed so as to be downshifted on the low vehicle speed side compared to the other cases. Yes. The changed downshift lines in this case are not individually illustrated, but for example, the changed downshift line Ld1m changed from the downshift line Ld1 is set to shift at a lower vehicle speed side than the corresponding changed upshift line Lc1. .

  Further, the engine ECC 30 indicates the output state of the differential pressure sensor 28 and the DPF upstream side exhaust pressure sensor 27 (a constant sensor output cannot be obtained or an abnormal value out of the normal sensor output range (so-called out of range)). ) To detect a failure of the differential pressure sensor 28 or the DPF upstream side exhaust pressure sensor 27 or a sensor output state similar thereto, and the ROM of the engine ECC 30 has a function for that purpose. A failure detection program is stored.

  Next, the operation will be described.

  In the control apparatus for a diesel vehicle as described above, the driving drive output is controlled by the engine ECC 30 and the automatic transmission ECC 40 as shown in a schematic procedure in FIG.

(Differential pressure sensor normal mode control)
First, in the normal control (normal shift control) state, whether or not the value of the differential pressure across the DPF exceeds the predetermined threshold value Δp1 for determining the differential pressure abnormality is determined based on the detection information of the differential pressure sensor 28 by the engine ECC 30. To determine whether the differential pressure across the DPF is abnormal or normal (step S11). If normal (if NO in step S11), the control returns to normal control, but if the differential pressure before and after is greater than Δp1, there is an abnormality. If it is determined, then a MIL (Malfunction Indicator Lamp) lamp, which is a failure display lamp, is turned on (step S12), and the component failure is detected by the differential pressure across the DPF with respect to the excessive differential pressure across the DPF. The maximum output of the engine 10 that can be continuously operated without causing expansion is, for example, the maximum output restriction map (see FIG. 4A) obtained in a previous experiment, the operating state of the engine 10 (engine speed, etc.) It is calculated based on (step S13). Note that the output of the differential pressure sensor 28 may exceed the abnormality determination threshold value Δp1 due to the relationship between the exhaust pulsation and the direction of increase / decrease change in the differential pressure before and after the DPF. However, it may return to the normal differential pressure range in a short time. Further, since the output of the engine 10 itself fluctuates, the output is limited only in the output region portion exceeding the output (engine speed and torque) in the limited region (see FIG. 4B).

  Next, it is determined whether or not the calculated maximum output exceeds a certain threshold value Hm (step S14), and when the calculated maximum output is less than or equal to a certain threshold value Hm (in the case of NO in step S14). In order to prevent damage to the DPF device 25, exhaust system oil seals, damage to the turbocharger due to temperature rise, etc., the vehicle is prohibited from running, for example, the process of forcibly returning the gears of the automatic transmission to neutral. This is done (step S15).

  On the other hand, if the calculated maximum output exceeds a certain threshold value Hm (YES in step S14), the maximum output of the engine 10 is controlled with the calculated maximum output as the upper limit value. (Step S16).

  Further, in the automatic transmission ECC 40, when the fact that the maximum output of the engine 10 is limited is transmitted as control information from the engine ECC 30, the accelerator opening is larger than a predetermined opening (and the maximum output of the engine 10 is limited). In the driving region, the upshift lines Lu1, Lu2, Lu3 and Lu4 in the shift map M are changed and changed in the respective high accelerator opening regions so that the upshifting is performed on the low vehicle speed side as compared with the normal case where the output is not limited. The shift schedule is changed so as to change to shift lines Lc1, Lc2, Lc3, and Lc4 (step S17). At this time, the upshift line is a limited maximum torque curve (engine) in a region exceeding the road load line corresponding to the accelerator opening when the vehicle travels on a flat road without acceleration / deceleration. It is set to upshift along the range in which the torque decreases as the rotational speed increases. Further, in the automatic transmission ECC 40, when the accelerator opening is larger than the predetermined opening and the maximum output of the engine 10 is limited, the amount of change of the upshift lines Lu1, Lu2, Lu3, and Lu4 to the low vehicle speed side Accordingly, the downshift lines Ld1, Ld2, Ld3, and Ld4 are changed to be downshifted on the low vehicle speed side as compared with other cases.

  Therefore, for example, in normal control, when traveling at the 1st speed with the maximum output of the accelerator opening 100 [%], it is upshifted to the 2nd speed at about 37 km / h, but in the case of the normal control when traveling at the 1st speed with the maximum output If the maximum output is limited so that the engine speed reaches 5200 rpm but only reaches about 4000 rpm, the engine ECC 30 provides information indicating the degree of restriction (limit range) of the output limit to the automatic transmission ECC 40. The automatic transmission ECC 40 serving as the shift condition switching means moves to the lower vehicle speed side of the upshift lines Lu1, Lu2, Lu3 and Lu4 according to the maximum output limit of the engine 10 by the engine ECC30 which is the output limiting means. Change amount (vehicle speed change amount to change upshift lines Lc1, Lc2, Lc3 and Lc4) That.

  When the shift schedule has been changed, it is then determined whether or not the differential pressure across the DPF is normal using a determination threshold Δp2 that is smaller than the determination threshold Δp1 for abnormality determination. That is, it is determined whether the DPF front-rear differential pressure is abnormal or normal depending on whether the DPF front-rear differential pressure value is equal to or less than a predetermined determination threshold value Δp2 for normal differential pressure determination (step S18). If it is abnormal, the processing after the maximum output calculation step is executed again.

(Differential pressure sensor failure mode control)
On the other hand, when the differential pressure sensor 28 breaks down or is temporarily unable to detect normal differential pressure, the engine ECC 30 and the automatic transmission ECC 40 control the travel drive output as shown in the schematic procedure of FIG. Executed.

  First, when a failure occurs such that the output of the differential pressure sensor 28 deviates from the normal range under the normal control state, the differential pressure sensor 28 is first failed by the engine ECC 30 based on the detection information of the differential pressure sensor 28. If it is normal (in the case of NO in step S21), it returns to normal control, but it is determined that the differential pressure sensor 28 has failed. Then, after the MIL lamp is turned on (step S22), the soot accumulated in the DPF device 25 based on the travel distance, the fuel injection amount, the detection information of the engine speed, and the like by a known estimation method. The amount is estimated (step S23). Next, it is determined whether or not the estimated soot accumulation amount exceeds a predetermined amount (step S24). If the estimated soot accumulation amount does not exceed the predetermined amount (NO in step S24), the estimated soot accumulation amount is determined. The soot combustion control is performed by performing the post-injection according to (step S25).

  If the estimated soot accumulation amount exceeds a predetermined amount (in the case of YES in step S24), the maximum output (shaft output) of the engine 10 that can continue operation without causing an increase in component failure with respect to the accumulation amount. However, as in the known method, for example, based on the torque reduction-PM accumulation amount map (see FIG. 6A) and the reduction coefficient-engine speed map (see FIG. 6B) stored in advance in the ROM. The torque reduction is calculated by multiplying the reduction coefficient so as to limit the maximum torque on the high rotation region side (step S26). The maximum output restriction at this time is, for example, that the output characteristic A in the maximum output region indicated by the solid line in FIG. 6C is shifted to the output characteristic B indicated by the broken line in the figure, and the maximum torque Ta indicated by the solid line is the broken line. Is limited to the maximum torque Tb indicated by. Next, the throttle opening and the fuel injection amount are limited, the calculated output limit is executed, and soot combustion control within a predetermined range is executed (step S27).

  On the other hand, in the automatic transmission ECC 40, when the fact that the maximum output of the engine 10 is limited is transmitted as control information from the engine ECC 30, the accelerator opening is larger than the predetermined opening (and the maximum output of the engine 10 is limited). In the driving region, the upshift lines Lu1, Lu2, Lu3 and Lu4 in the shift map M are changed and changed in the respective high accelerator opening regions in order to upshift on the low vehicle speed side compared to the normal case where the output is not limited. The shift schedule is changed so as to change to shift lines Lc1, Lc2, Lc3, and Lc4 (step S28). The upshift line at this time is a curve of the limited maximum torque Tb within the region exceeding the road load line corresponding to the accelerator opening when the vehicle travels on a flat road without acceleration / deceleration. Is set to upshift.

  Next, it is determined again whether or not the differential pressure sensor 28 is out of order (in the output state of the failure range) (step S29). If the sensor returns to the normal sensor output state (NO in step S29). When it is determined that the differential pressure sensor 28 has failed, the MIL lamp is turned on again (step S22), and the amount of soot accumulated in the DPF device 25 is estimated. Processes after the step are executed (steps S23 to S29).

  As described above, in the control device for the diesel vehicle of the present embodiment, when the particulate matter is accumulated in a predetermined amount or more on the filter even by the filter regeneration process of the DPF device 25, the engine ECC 30 serving as the output limiting means causes the maximum of the engine 10. When the output is limited, the accelerator opening is larger than the predetermined opening, and the maximum output of the engine 10 is limited, the upshift is performed on the low vehicle speed side compared to the case where the maximum output of the engine is not limited. Upshift lines Lu1 to Lu4 in the shift diagram M are changed to changed upshift lines Lc1 to Lc4. Therefore, although the accelerator opening is large, the engine speed has not been increased as normal due to the limitation of the maximum engine output, and even when the vehicle speed cannot be increased sufficiently, it has been changed to upshift at a lower vehicle speed than usual. When the vehicle speed increases across the shift line or the accelerator opening increases, an upshift to the next gear stage is performed, ensuring sufficient traveling performance and improving fuel efficiency.

  Further, since the amount of change of the upshift lines Lu1 to Lu4 to the low vehicle speed side is determined according to the limit amount of the engine maximum output, the upshift is performed at an appropriate timing according to the limit amount of the maximum output of the engine 10. It will be.

  Further, when the accelerator opening is larger than the predetermined opening and the maximum output of the engine 10 is limited, the response in the shift diagram is changed according to the amount of change of the upshift lines Lu1 to Lu4 to the low vehicle speed side. The downshift lines Ld1 to Ld4 to be changed are downshifted on the low vehicle speed side as compared with other cases, so the upshift lines Lu1 to Lu4 on the low vehicle speed side change upshift line Lc1 in the high accelerator opening range. Depending on the amount of change to ~ Lc4, the corresponding downshift lines Ld1 to Ld4 are changed to the low vehicle speed side (for example, Ld1m), and stable generation with reduced occurrence of hunting in the automatic transmission 60 is achieved. Driving performance is ensured.

(Other embodiments)
In the above-described embodiment, when the shift condition switching means is configured by the automatic transmission ECC 40, and the accelerator opening is larger than the predetermined opening and the maximum output of the engine 10 is limited, the maximum output of the engine The upshift lines Lu1 to Lu4 of the shift diagram M are changed to the changed upshift lines Lc1 to Lc4 so that the upshift is performed on the low vehicle speed side as compared with the case where the speed is not limited. Another embodiment for performing switching will be described.

  Since the hardware configuration of the present embodiment is substantially the same as that of the above-described embodiment, only the differences will be described using the reference numerals of the components in the above-described embodiment.

  In the present embodiment, the ROM of the automatic transmission ECC 40 stores a program that exhibits a function as a traveling load detection unit that detects the current traveling load of the vehicle based on the accelerator opening and the vehicle speed. In addition, when the accelerator opening is larger than the predetermined opening and the maximum output of the engine 10 is limited, and the traveling load of the vehicle is larger than the predetermined value, the automatic transmission ECC 40 detects the traveling load detecting means. Based on the detected information, the change of the upshift lines Lu1, Lu2, Lu3 and Lu4 to the low vehicle speed side (change to the changed upshift lines Lc1 to Lc4) by the function of the shift condition switching means is prohibited. ing.

  In the present embodiment, when the traveling load is large, the upshift lines Lu1 to Lu4 are prohibited from changing to the low vehicle speed side. Therefore, when the traveling load is large, the torque becomes insufficient and the vehicle speed decreases. Thus, an upshift of the automatic transmission 60 is avoided, and stable running performance is ensured.

  In each of the above-described embodiments, the automatic transmission 60 is not limited to a combination of a torque converter and a multi-stage transmission having a planetary gear, and a clutch or gear box while controlling the throttle opening by electronic control. The present invention can be applied to a so-called multimode manual transmission (automatic control type manual transmission) in which the actuator is controlled to automatically shift, and can also be applied to a continuously variable transmission.

  In addition, even in a diesel vehicle using a manual transmission in which the driver performs the shifting operation himself, the shift position is displayed and a suitable upshift or downshift timing is set to “UP”, “DOWN”, or the corresponding upper and lower When equipped with a shift indicator that is displayed with an arrow, etc., the normal upshift line and the modified upshift are changed so that the upshift or downshift timing when the maximum output is limited is changed earlier than usual (low vehicle speed side). Even if an ECU (electronic control unit) is equipped with a shift diagram for an indicator including a line, as in the case of the above-described embodiment, the maximum output of the engine when the filter is excessively collected Operation that cannot be upshifted with normal operation feeling while restricting to prevent component failure To prevent the frequency occurs, it is possible to secure a sufficient driving performance and operation feeling. Therefore, the present invention can also be applied to a diesel vehicle control device in which a transmission is a manual transmission (manual transmission) and a shift indicator is mounted.

  As described above, the present invention has a large accelerator opening, but the engine speed does not increase as usual due to the limitation of the maximum engine output, and even when the vehicle speed cannot be sufficiently increased, the vehicle speed is increased faster than usual. Upshift to the next gear stage when the vehicle speed rises or the accelerator opening increases across the upshift line that has been changed to upshift. It is possible to provide a control device for a diesel vehicle that can reliably prevent the occurrence of an operation region that cannot be upshifted and ensure sufficient running performance while preventing parts failure. All the control devices for diesel vehicles that perform regeneration control of the DPF device and limit engine output when the DPF device accumulates soot It is useful to.

It is the schematic block diagram which shows one Embodiment of the control apparatus of the diesel vehicle of this invention. It is a shift diagram memorized and stored in a control device of a diesel car of one embodiment. It is a flowchart which shows the general | schematic flow of the control program at the time of the differential pressure sensor normal mode performed with the control apparatus of one Embodiment diesel vehicle. It is explanatory drawing which shows typically the maximum output limitation content of the engine performed with the control apparatus of one embodiment diesel vehicle. It is a flowchart which shows the general | schematic flow of the control program at the time of the differential pressure sensor failure mode performed with the control apparatus of one embodiment diesel vehicle. (A) is an explanatory view of a torque reduction-PM accumulation amount map stored in the diesel vehicle control device of one embodiment, and (b) is a reduction coefficient stored in the diesel vehicle control device of one embodiment-engine rotation. FIG. 6C is a graph showing the maximum output restriction content of the engine executed by the diesel vehicle control device of the embodiment in terms of torque characteristics, with the vertical axis representing the output and torque, and the horizontal axis representing the engine. The number of rotations is shown.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Engine 11 Cylinder 12 Fuel injection valve 13 Combustion chamber 14 Exhaust device 15 Supercharger 15a Intake air compressor 15b Exhaust turbine 16 Intake passage 19 Fuel injection valve for back injection 21 Exhaust manifold 22 Downstream exhaust pipe 23 Oxidation catalyst 25 DPF Equipment (filter)
26a, 26b Exhaust temperature sensor 27 DPF upstream exhaust pressure sensor 28 Differential pressure sensor 30 Engine ECC (regeneration processing means, output limiting means)
40 Automatic transmission ECC (shift instruction means, shift condition switching means)
41 accelerator opening sensor (accelerator opening detecting means)
42 Vehicle speed sensor (vehicle speed detection means)
43 Crank angle sensor (engine speed detection means)
60 Automatic transmission (transmission)
Lc1, Lc2, Lc3, Lc4 Change upshift line Ld1, Ld2, Ld3, Ld4 Downshift line Ld1m Change downshift line Lu1, Lu2, Lu3, Lu4 Upshift line

Claims (6)

A control device for a diesel vehicle equipped with an engine and a transmission,
Regeneration processing means for performing regeneration processing of the filter when the particulate matter is deposited on a filter that collects particulate matter in the exhaust gas of the engine;
Output limiting means for limiting the maximum output of the engine when the particulate matter is accumulated in the filter in a predetermined amount or more;
An accelerator opening detecting means for detecting an accelerator opening of the vehicle;
Vehicle speed detecting means for detecting the vehicle speed of the vehicle;
Shift diagram storage means for storing a shift diagram that defines a shift stage of the transmission according to the accelerator opening and the vehicle speed;
Shift instruction means for selecting and instructing the gear position of the transmission according to the accelerator opening and the vehicle speed according to the shift map;
When the accelerator opening is larger than a predetermined opening and the maximum output of the engine is limited, the shift map is used to upshift on the low vehicle speed side compared to the case where the maximum output of the engine is not limited. A shift condition switching means for changing the upshift line in the diesel vehicle control device.   2. The diesel according to claim 1, wherein the shift condition switching unit determines a change amount of the upshift line to a low vehicle speed side according to a limit amount of the maximum output of the engine by the output limiting unit. Car control device. A travel load detecting means for detecting the travel load of the vehicle;
When the accelerator opening is larger than a predetermined opening and the maximum output of the engine is limited, and the traveling load of the vehicle is larger than a predetermined value, based on detection information of the traveling load detection means, The diesel vehicle control device according to claim 1 or 2, wherein the shift condition switching means prohibits the upshift line from being changed to a low vehicle speed side.   When the accelerator opening is larger than a predetermined opening and the maximum output of the engine is limited, the shift condition switching means changes the shift according to the amount of change of the upshift line to the low vehicle speed side. 4. The diesel vehicle control device according to claim 1, wherein a corresponding downshift line in the diagram is changed so as to be downshifted at a lower vehicle speed side than in the other cases. 5. .   5. The diesel vehicle according to claim 1, wherein the transmission is configured by an automatic transmission capable of automatically shifting to a shift stage selected and instructed by the shift instruction means. Control device.   5. The diesel vehicle according to claim 1, wherein the transmission is configured by a manual transmission, and the shift instruction unit is configured by a shift indicator that displays an upshift timing. 6. Control device.

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