JP5559907B2 - Engine control device - Google Patents

Description

  The present invention relates to an engine control device mounted on a work vehicle such as a tractor and a control method therefor.

  In recent engines, a common rail fuel injection device is used to supply high pressure fuel to the injector for each cylinder, and the injection pressure, injection timing, and injection period (injection amount) of the fuel from each injector are electronically controlled. Thus, there is known a technique for reducing nitrogen oxide (NOx) discharged from the engine and reducing noise and vibration of the engine (see Patent Document 1).

Japanese Patent Laid-Open No. 10-9033

  By the way, in a work vehicle such as a tractor equipped with this type of engine, the ECU controls the operation of the common rail fuel injection device based on output characteristic data such as a map format and a function table format, a rotational speed and a torque. The engine output is adjusted by the fuel injection amount corresponding to the operation amount of the shift lever or the like. The output characteristic data corresponds to the work vehicle on which the engine is mounted, and usually only one type or a limited type is stored in the ECU. Therefore, the conventional configuration has a problem that even if the engine type is the same, for example, the ECU of the tractor engine is difficult to apply as the ECU of the backhoe engine (that is, the versatility of the ECU is low). It was. Such a problem exists not only in the common rail fuel injection device but also in the electronic governor type.

  Therefore, the present invention has a technical problem to solve the above problems.

The present invention is based on an engine, a fuel injection device that injects fuel into the engine, detection means that detects a driving state of the engine, detection information of the detection means, and output characteristic data unique to the engine. An engine control device comprising an ECU for controlling the operation of the fuel injection device, wherein the ECU includes a first area in which the output characteristic data is written, and a correction for correcting the operation of the fuel injection device is provided with a second area writable property data, further wherein comprises a prohibiting means for prohibiting writing to the second area, wherein the first area while the output characteristics data is written, the the second area is shipped without writing the modified characteristic data, when mounting the engine to the work vehicle, the writing by the inhibiting means Is locked state is canceled, the correction characteristic data suitable for working characteristics of the working vehicle in the area is that written.

In the present invention, based on an engine, a fuel injection device that injects fuel into the engine, detection means that detects a driving state of the engine, detection information of the detection means, and output characteristic data unique to the engine An engine control device comprising an ECU for controlling the operation of the fuel injection device, wherein correction characteristic data for correcting the operation of the fuel injection device is written in the ECU separately from the output characteristic data The ECU in which the correction characteristic data is written inquires the correction characteristic data based on the detection information of the detection means, and operates the fuel injection device based on the inquiry result. It may be configured to allow the above .

In the engine control device, the ECU in which the correction characteristic data is written selectively inquires the correction characteristic data based on detection information of the detection means, and operates the fuel injection device based on the inquiry result. It doesn't matter if you let it.

In the engine control unit, after the correction characteristic data has been normally written, it may be a rewriting of the corrected characteristic data as shall be configured so as to prohibit the hardware or software.

In the engine control device, each characteristic data is data indicating a relationship between a rotational speed and torque in the engine, and the correction characteristic data is a torque limit for a predetermined rotational speed as compared with the output characteristic data. It is set to may be as shall.

The present invention is based on an engine, a fuel injection device that injects fuel into the engine, detection means that detects a driving state of the engine, detection information of the detection means, and output characteristic data unique to the engine. An engine control device comprising an ECU for controlling the operation of the fuel injection device, wherein the ECU includes a first area in which the output characteristic data is written, and a correction for correcting the operation of the fuel injection device is provided with a second area writable property data, further wherein comprises a prohibiting means for prohibiting writing to the second area, wherein the first area while the output characteristics data is written, the the second area is shipped without writing the modified characteristic data, when mounting the engine to the work vehicle, the writing by the inhibiting means Since the stopped state is released and the correction characteristic data that matches the work characteristics of the work vehicle is written to the area, even the engine manufacturer can write / rewrite to the area and extract the written contents. (Reverse engineering) can be disabled. Therefore, there is an advantage that important information (the correction characteristic data) of the engine purchase manufacturer can be surely protected.

According to the present invention, based on an engine, a fuel injection device that injects fuel into the engine, detection means that detects a driving state of the engine, detection information of the detection means, and output characteristic data unique to the engine An engine control device comprising an ECU for controlling the operation of the fuel injection device, wherein the ECU has correction characteristic data for correcting the operation of the fuel injection device separately from the output characteristic data. The ECU in which the correction characteristic data is written can inquire the correction characteristic data based on the detection information of the detection means, and operate the fuel injection device based on the inquiry result. If the engine model is the same, any output characteristic data stored in the ECU will be stored. A different ECU can be designed and manufactured separately for each vehicle type on which the engine is mounted and each work machine (cultivator, plow, bucket, etc.) mounted on the work vehicle. There is no need to prepare various ECUs. Therefore, only one type of ECU needs to be designed and manufactured for one type of engine, and the versatility of the ECU can be greatly improved.

  In addition, when it is desired to execute optimal fuel injection control for each vehicle type on which the engine is mounted or for each work machine mounted on the work vehicle, for example, an engine manufacturer such as a work vehicle manufacturer who purchases the engine. Other than the above, it is sufficient to write the correction characteristic data into the ECU. Therefore, the versatility of the ECU can be remarkably improved, and the flexibility (flexibility) of the ECU with respect to fuel injection control can be easily and reliably ensured.

According to the present invention, the ECU in which the correction characteristic data is written alternatively inquires the correction characteristic data based on the detection information of the detection means, and operates the fuel injection device based on the inquiry result. From the specific ones that have written the correction characteristic data in the ECU (for example, those other than engine manufacturers such as a work vehicle manufacturer who purchases the engine), the initial output characteristic data is deleted one by one, There is no need to change the control program. Therefore, the engine output characteristics data can be changed, but the engine is very easy to handle.

In the present invention, after the correction characteristic data is normally written , the correction characteristic data is written to the ECU by prohibiting rewriting of the correction characteristic data in terms of hardware or software. It is possible to prevent other than specific ones from easily rewriting the modified specific data using, for example, an unauthorized tool. This is highly effective in terms of security after writing the modified specific data.

In the present invention, each characteristic data is data indicating a relationship between a rotation speed and torque in the engine, and the correction characteristic data is to limit the torque with respect to a predetermined rotation speed as compared with the output characteristic data. Therefore, in the fuel injection control using the correction characteristic data, the fuel injection is suppressed more than in the fuel injection control using the output characteristic data. Therefore, although it is possible to select the optimal fuel injection control for each vehicle type on which the engine is mounted or for each work machine mounted on the work vehicle, one type of ECU is used for one type of engine. This has the effect of dealing with exhaust gas regulations and taking environmental pollution into consideration.

It is a conceptual explanatory drawing which summarized this invention. It is a conceptual explanatory view showing the state of the ECU before and after engine shipment. It is fuel system explanatory drawing of a diesel engine. It is explanatory drawing of an output characteristic map. It is explanatory drawing of a correction characteristic map. It is a flowchart of a writing / rewriting process. It is a flowchart of fuel injection control. It is explanatory drawing of the correction characteristic map of a 1st another example. It is explanatory drawing which shows the relationship between the rotational speed and torque in a 2nd example. It is a flowchart of the fuel injection control of the 2nd example. It is an external appearance perspective view of a diesel engine. It is a side view of the intake manifold installation side of a diesel engine. It is a side view of the exhaust manifold installation side of a diesel engine. It is a side view of the flywheel installation side of a diesel engine. It is a side view of the cooling fan installation side of a diesel engine. It is a top view of a diesel engine. It is a side view of a tractor. It is a top view of a tractor.

  Hereinafter, an embodiment in which the present invention is embodied will be described with reference to the drawings when applied to a diesel engine mounted on a tractor as a work vehicle. In the description of the diesel engine from FIG. 11 to FIG. 16, the intake manifold installation side of the diesel engine is “right side” and the exhaust manifold installation side is “left side”. It is a standard for positional relationships.

(1). First, the fuel system structure of the common rail system 117 (common rail fuel injection device) and the diesel engine 70 will be described with reference mainly to FIG. As shown in FIG. 3, a fuel tank 118 is connected to each of the four cylinder injectors 115 provided in the diesel engine 70 via a common rail system 117 and a fuel supply pump 116. Each injector 115 is provided with an electromagnetic switching control type fuel injection valve 119. The common rail system 117 includes a cylindrical common rail 120.

  As shown in FIG. 3, a fuel tank 118 is connected to the suction side of the fuel supply pump 116 via a fuel filter 121 and a low pressure pipe 122. The fuel in the fuel tank 118 is sucked into the fuel supply pump 116 via the fuel filter 121 and the low pressure pipe 122. The fuel supply pump 116 of the embodiment is disposed in the vicinity of the intake manifold 73. Specifically, the cylinder block 75 is provided on the right side surface (the intake manifold 73 installation side) and below the intake manifold 73. On the other hand, the common rail 120 is connected to the discharge side of the fuel supply pump 116 via a high-pressure pipe 123. In addition, injectors 115 for four cylinders are connected to the common rail 120 via four fuel injection pipes 126, respectively.

  With the above configuration, the fuel in the fuel tank 118 is pumped to the common rail 120 by the fuel supply pump 116, and high-pressure fuel is stored in the common rail 120. Each fuel injection valve 119 is controlled to open and close, whereby high-pressure fuel in the common rail 120 is injected from each injector 115 to each cylinder of the diesel engine 70. That is, by electronically controlling each fuel injection valve 119, the injection pressure, injection timing, and injection period (injection amount) of the fuel supplied from each injector 115 are controlled with high accuracy. Therefore, nitrogen oxide (NOx) from the diesel engine 70 can be reduced, and noise vibration of the diesel engine 70 can be reduced.

  As shown in FIG. 3, a fuel supply pump 116 is connected to the fuel tank 118 via a fuel return pipe 129. A common rail return pipe 131 is connected to the end of the cylindrical common rail 120 in the longitudinal direction via a return pipe connector 130 that limits the pressure of fuel in the common rail 120. That is, surplus fuel from the fuel supply pump 116 and surplus fuel from the common rail 120 are collected in the fuel tank 118 via the fuel return pipe 129 and the common rail return pipe 131.

(2). Next, fuel injection control of the common rail 120 will be described with reference to FIGS. As shown in FIG. 3, an ECU 11 (integrated ECU) that operates a fuel injection valve 119 of each cylinder in the diesel engine 70 is provided. Although not shown in detail, the ECU 11 is a CPU that executes various arithmetic processes and controls, an EEPROM that stores control programs and data, a flash memory, a RAM that temporarily stores control programs and data, a CAN controller, and an input / output An interface or the like is provided, and the diesel engine 70 or the vicinity thereof is disposed.

  On the input side of the ECU 11, at least the rail pressure sensor 12 that detects the fuel pressure in the common rail 120, the electromagnetic clutch 13 that rotates or stops the fuel pump 116, the rotational speed of the diesel engine 70 (the camshaft position of the crankshaft 74). ) For detecting and setting the number of fuel injections of the injector 115 (the number of fuel injections during the fuel injection period of one stroke), and an accelerator operating tool such as a throttle lever or an accelerator pedal. A throttle position sensor 16 that detects the operation position (not shown), a turbo booster sensor 17 that detects the pressure of the turbocharger 100, an intake air temperature sensor 18 that detects the intake air temperature of the intake manifold 73, and a diesel engine 70 A cooling water temperature sensor 19 for detecting the temperature of the cooling water of It has been continued. These sensors 12 to 19 constitute detection means for detecting the driving state of the diesel engine 70.

  Further, the solenoids of the fuel injection valves 119 for at least four cylinders are respectively connected to the output side of the ECU 11. That is, the high-pressure fuel stored in the common rail 120 is injected from the fuel injection valve 119 in a plurality of times during one stroke while controlling the fuel injection pressure, the injection timing, the injection period, and the like, so that nitrogen oxide (NOx ), And complete combustion with reduced generation of soot and carbon dioxide is performed to improve fuel efficiency.

  As shown in FIGS. 1 to 3, the ECU 11 (for example, storage means, flash memory, EEPROM, etc.) is provided with a manufacturing area U1 for an engine manufacturer and a purchasing area U2 for an engine purchase manufacturer. Yes. In the manufacturing area U1 of the ECU 11, an output characteristic map M1 (see FIG. 4) as output characteristic data indicating the relationship between the rotational speed N of the diesel engine 70 and the torque T (load) is stored in advance. This kind of output characteristic map M1 is obtained by experiments or the like. The output characteristic data is not limited to the map format as in the embodiment, and may be a function table, set data (data table), or the like. In the output characteristic map M1 shown in FIG. 4, the rotational speed N is taken on the horizontal axis and the torque T is taken on the vertical axis. In the output characteristic map M1, a solid line Tmx1 drawn in an upwardly convex curve is a maximum torque line representing the maximum torque for each rotational speed N. In this case, if the model of the diesel engine 70 is the same, the output characteristic maps M1 stored in the manufacturing side area U1 of the ECU 11 are all the same (common).

  The ECU 11 basically obtains the torque T from the rotational speed N detected by the engine speed sensor 14 and the throttle position detected by the throttle position sensor 16, and uses the torque T and the output characteristic map M1 to perform target fuel injection. The fuel injection control for calculating the amount R and operating the common rail system 117 based on the calculation result is executed. Here, the fuel injection amount is adjusted by adjusting the valve opening period of each fuel injection valve 119 and changing the injection period to each injector 115.

  As shown in FIGS. 1 to 3, the purchase side area U <b> 2 of the ECU 11 is an area in which data other than the manufacturer of the diesel engine 70 (for example, a vehicle manufacturer who purchases the diesel engine 70) writes data. Yes. In the purchase area U2, in addition to the output characteristic map M1, a correction characteristic map M2 as correction characteristic data for correcting the operation of the common rail system 117 is displayed. Is written after shipment (see FIG. 2). The correction characteristic map M2 written later indicates the relationship between the rotational speed N of the diesel engine 70 and the torque T (load), similarly to the output characteristic map M1 of the ECU 11. Also in the correction characteristic map M2 shown in FIG. 5, the rotational speed N is taken on the horizontal axis and the torque T is taken on the vertical axis. In the correction characteristic map M2, a solid line Tmx2 drawn in an upward convex curve is a maximum torque line representing the maximum torque for each rotational speed N. The correction characteristic data is not limited to the map format as in the embodiment, but may be a function table, set data (data table), or the like, as with the output characteristic data.

  The correction characteristic map M2 (shown by a solid line in FIG. 5) is set so as to limit the torque T with respect to the predetermined rotational speed N as compared with the output characteristic map M1 (shown by a broken line in FIG. 5). That is, the maximum torque at the same rotational speed N is smaller than that obtained from the correction characteristic map M2 than that obtained from the output characteristic map M1 (Tmx1 ≦ Tmx2), so that the correction characteristic map M2 and the output characteristic map M1 The relationship is set (set so that the maximum torque line Tmx2 on the modified characteristic map M2 side is positioned inside (lower side) the maximum torque line Tmx1 on the output characteristic map M1 side).

  Even if the model of the diesel engine 70 is the same, the correction characteristic map M2 stored in the purchase-side area U2 of the ECU 11 is a work machine (cultivator) mounted on the work vehicle or for each vehicle type on which the diesel engine 70 is mounted. , Plows, buckets, etc.). As an example of the setting of the correction characteristic map M2, for example, in order to suppress the engine stall with respect to work with large load fluctuations, output characteristics for obtaining a high torque over a wide range of rotational speeds, or for work with small load fluctuations. On the other hand, output characteristics that reduce rotation fluctuation due to load fluctuations in order to increase work efficiency, and output characteristics that reduce rotation speed before connection in order to reduce the shock of connection to clutch connection work. Etc. are considered.

  The ECU 11 in which the correction characteristic map M2 is written in the purchase side area U2 preferentially inquires the correction characteristic map M2 instead of the output characteristic map M1, and determines the torque T based on the detected values of the engine speed sensor 14 and the throttle position sensor 16. Is calculated to obtain the target fuel injection amount R, and the common rail system 117 is operated based on the inquiry calculation result (performed execution of the corrected fuel injection control using the corrected characteristic map M2 is permitted) ( (See FIG. 1).

  Here, for example, when a function (formula) or set data is adopted as the correction characteristic data, the limit torque value is calculated from the detection values of the engine speed sensor 14 and the throttle position sensor 16, the output characteristic data, and the correction characteristic data. And the target fuel injection amount R is obtained, and the common rail system 117 is operated based on the calculation result (so that the torque T with respect to the predetermined rotational speed N is limited).

  It is also possible to provide selection means for setting whether or not to use the modified characteristic map M2 (may be referred to as selection means for alternatively selecting the characteristic maps M1 and M2). As a selection means, the structure selected with the jumper pin provided in ECU11 or the selection switch provided in the cabin of the working vehicle can be considered. Alternatively, the characteristic maps M1 and M2 may be selected by a control signal from a main unit ECU (another ECU) provided in the work vehicle.

  In addition, it is prohibited for anyone other than a specific one (for example, a written vehicle manufacturer or its dealer) to write in the purchase area U2 or rewrite the correction characteristic map M2 normally written in the purchase area U2. It is also possible to do. Needless to say, as a measure for prohibiting writing, for example, a hardware-like method such as a write-inhibiting method in a flexible disk may be used, or a software method such as a key collating method may be used.

  As shown in FIGS. 1 and 2, the engine control apparatus of the embodiment writes the output characteristic map M1 in the manufacturing side area U1 of the ECU 11 and does not write the correction characteristic map M2 in the purchase side area U2. Shipped from the engine manufacturer. The purchase-side area U2 is set to be writable / rewritable only by the engine purchase manufacturer and not writable / rewritable by the engine manufacturer by the hardware or software prohibition means as described above. In the purchase side area U2 of the ECU 11, when the engine purchase manufacturer mounts the diesel engine 70 on the work vehicle, a correction characteristic map M2 adapted to the work characteristics of the work vehicle is written.

  FIG. 6 is a flowchart showing a write / rewrite process to the purchase-side area U2 as an example of a prohibition unit. The writing / rewriting process is performed not by the engine manufacturer but by the engine purchase manufacturer. When the engine purchase manufacturer first writes the correction characteristic map M2 in the purchase-side area U2 of the ECU 11, for example, a manufacturer ID (unique information) unique to the engine purchase manufacturer is written together. The manufacturer ID is set so as not to be overwritten, and is deleted only when the purchase area U2 is initialized. As shown in FIG. 6, when the ECU 11 receives a write request signal from a writing tool (not shown) of the engine purchase manufacturer (step S31: YES), it is determined whether or not the manufacturer ID has already been written in the purchase area U2. (Step S32). If the manufacturer ID is not written (S32: NO), the manufacturer ID and the correction characteristic map M2 are written in the purchase area U2 (step S33). When the manufacturer ID has been written (S32: YES), only when the written manufacturer ID matches the signal (maker ID) from the writing tool (S34: YES), the purchase side area U2 is entered. Writing / rewriting is permitted, and only the new correction characteristic map M2 from the writing tool is overwritten (step S35). If they do not match (S34: NO), writing / rewriting to the purchase-side area U2 is prohibited (step S36), and the process ends.

(3). Description of Fuel Injection Control Next, an example of fuel injection control will be described with reference to the flowchart of FIG. As described above, since the correction characteristic map M2 is written in the purchase area U2, the ECU 11 of the embodiment inquires the correction characteristic map M2 preferentially and detects the engine speed sensor 14 and the throttle position sensor 16. The torque T is calculated from the value to obtain the target fuel injection amount R, and the common rail system 117 is operated based on the inquiry calculation result. In this case, as shown in the flowchart of FIG. 7, the ECU 11 determines which characteristic map is to be selected (step S1). In the embodiment, it is determined whether or not the correction characteristic map M2 is written in the purchase side area U2. When the output characteristic map M1 is selected (without writing), the detected values of the engine speed sensor 14 and the throttle position sensor 16 are read at a predetermined timing (appropriately every time) (step S2), and then the ECU 11 has its own output. The characteristic map M1 is inquired, and the target fuel injection amount R is calculated by obtaining the torque T from the rotational speed N and the throttle position read earlier (step S3). Then, the common rail system 117 is operated based on the target fuel injection amount R (step S4). Thereafter, if the key switch for power supply (not shown) is turned on, the process returns to step S2 to continue the fuel injection control using the output characteristic map M1.

  When the correction characteristic map M2 is selected (with writing), the detection values of the engine speed sensor 14 and the throttle position sensor 16 are read at a predetermined timing (step S5), and then the ECU 11 corrects the correction characteristic map in the purchase area U2. M2 is inquired, torque T (limit torque value) is obtained from the rotational speed N and throttle position read earlier, and the target fuel injection amount R is calculated (step S6). Then, the common rail system 117 is operated based on the target fuel injection amount R (step S7). Thereafter, if the key switch for power supply (not shown) is turned on, the process returns to step S5, and the corrected fuel injection control using the corrected characteristic map M2 is continued.

  As apparent from the above description and FIGS. 1 to 7, the engine 70, the fuel injection device 117 that injects fuel into the engine 70, detection means 14 and 16 that detect the driving state of the engine 70, and The ECU 11 includes an ECU 11 that controls the operation of the fuel injection device 117 based on detection information of the detection means 14 and 16 and output characteristic data M1 unique to the engine 70. The ECU 11 includes: In addition to the output characteristic data M1, there is provided an area U2 in which correction characteristic data M2 for correcting the operation of the fuel injection device 117 can be written, and the correction characteristic data M2 is not written in the area U2. When the engine 70 is mounted on a work vehicle, the area U2 conforms to the work characteristics of the work vehicle. Since serial corrected characteristic data M2 are written, the long type of engine 70 are the same, can be output characteristic data M1 stored in the ECU11 to those either identical (common). Further, for an engine purchase manufacturer who mounts the engine 70 on a work vehicle, the correction characteristic data M2 adapted to the work characteristic of the work vehicle can be written to the area U2 later. Therefore, it is possible to improve the versatility of the ECU for an engine manufacturer that manufactures the engine 70, and to ensure compatibility of the ECU with the work vehicle for an engine purchase manufacturer.

  Further, as apparent from the above description and FIGS. 1 to 7, the engine 70, the fuel injection device 117 that injects fuel into the engine 70, and the detection means 14 and 16 that detect the driving state of the engine 70, A control method for an engine control device comprising an ECU 11 for controlling the operation of the fuel injection device 117 based on detection information of the detection means 14 and 16 and output characteristic data M1 unique to the engine 70, In addition to the output characteristic data M1, the ECU 11 is provided with an area U2 in which correction characteristic data M2 for correcting the operation of the fuel injection device 117 can be written. The area U2 includes the correction characteristic data. When the engine 70 is mounted on the work vehicle and shipped without the data M2 being written, the work vehicle is installed in the area U2. The corrected characteristic data M2 suitable for the characteristic is written, and the ECU 11 to which the corrected characteristic data M2 is written inquires the corrected characteristic data M2 based on the detection information of the detection means 14 and 16, and the inquiry result Therefore, the engine 70 is operated using the correction characteristic data M2 adapted to the work characteristics of the work vehicle on which the engine 70 is mounted, regardless of the initial setting of the engine 70. You can control it. Therefore, it is easy for the engine purchase manufacturer to set to the company's specifications, and even the engine 70 purchased from the outside can be easily changed to the optimum setting for the company's use and provide an easy-to-use work vehicle. Play.

  As apparent from the above description and FIGS. 1 to 7, the engine 70, the fuel injection device 117 that injects fuel into the engine 70, detection means 14 and 16 that detect the driving state of the engine 70, and The ECU 11 includes an ECU 11 that controls the operation of the fuel injection device 117 based on detection information of the detection means 14 and 16 and output characteristic data M1 unique to the engine 70. The ECU 11 includes: In addition to the output characteristic data M1, an area U2 in which correction characteristic data M2 for correcting the operation of the fuel injection device 117 can be written is provided, and a prohibition unit for prohibiting writing to the area U2 is provided. In the area U2, the modified characteristic data M2 is not written and the engine 70 is mounted on a work vehicle. In this case, the write prohibition state by the prohibiting means is released, and the correction characteristic data M2 adapted to the work characteristics of the work vehicle is written in the area U2. Therefore, even in the engine manufacturer, the area U2 It is possible to make it impossible to write / rewrite data to and to extract written contents (reverse engineering). Therefore, there is an advantage that important information (the correction characteristic data M2) of the engine purchase manufacturer can be reliably protected.

  As apparent from the above description and FIGS. 1 to 7, the engine 70, the fuel injection device 117 that injects fuel into the engine 70, detection means 14 and 16 that detect the driving state of the engine 70, and The ECU 11 includes an ECU 11 that controls the operation of the fuel injection device 117 based on detection information of the detection means 14 and 16 and output characteristic data M1 unique to the engine 70. The ECU 11 includes: Apart from the output characteristic data M1, it is possible to write correction characteristic data M2 for correcting the operation of the fuel injection device 117, and the ECU 11 in which the correction characteristic data M2 has been written is used for the detection. The modified characteristic data M2 is inquired based on the detection information of the means 14, 16, and the fuel injection device 117 is inquired based on the inquiry result. Since the engine 70 is configured to be allowed to operate, the output characteristic data M1 stored in the ECU 11 can be the same (common) as long as the model of the engine 70 is the same. It is necessary to design and manufacture a different ECU 11 for each work model (cultivator, plow, bucket, etc.) mounted on the work vehicle 201 and prepare a wide variety of ECUs 11. Absent. Therefore, only one type of ECU 11 needs to be designed and manufactured for one type of engine 70, and the versatility of the ECU 11 can be greatly improved.

  In addition, when it is desired to execute optimum fuel injection control for each vehicle type on which the engine 70 is mounted or for each work machine mounted on the work vehicle 201, for example, a work vehicle manufacturer who purchases the engine 70 It is sufficient that a person other than the engine manufacturer writes the correction characteristic data M2 in the ECU 11. Therefore, the versatility of the ECU 11 can be remarkably improved, and the flexibility (flexibility) of the ECU 11 with respect to fuel injection control can be easily and reliably ensured.

  As apparent from the above description and FIG. 7, the ECU 11 in which the correction characteristic data M2 is written is configured to preferentially inquire the correction characteristic data M2 based on detection information of the detection means 14 and 16. Therefore, the specific data (for example, other than the engine manufacturer such as the work vehicle manufacturer who purchases the engine 70) in which the correction characteristic data M2 is written in the ECU 11 is the output characteristic data M1 that is initially set. There is no need to delete each one or change the control program. Therefore, while the output characteristic data M1 of the engine 70 can be changed, the handleability of the engine 70 is very good.

  As is apparent from the above description, the ECU 11 is configured to prohibit the rewriting of the correction characteristic data M2 in terms of hardware or software after the correction characteristic data M2 is normally written. It is possible to prevent the modified specific data M2 from being easily rewritten by using, for example, an unauthorized tool other than the specific one in which the modified characteristic data M2 is written. This is highly effective in terms of security after the modification specific data M2 is written.

  As apparent from the above description and FIG. 6, the characteristic data M1 and M2 are data indicating the relationship between the rotational speed N and the torque T in the engine 70, and the correction characteristic data M2 is the output characteristic. Since it is set to limit the torque T with respect to the predetermined rotational speed N as compared with the data M1, the fuel injection control using the correction characteristic data M2 is more fuel than the fuel injection control using the output characteristic data M1. Injection is suppressed. Therefore, the optimal fuel injection control can be selected for each vehicle type on which the engine 70 is mounted or for each work machine mounted on the work vehicle 201, but for the one-type engine 70, there is one type. The ECU 11 can cope with exhaust gas regulations and consider environmental pollution.

  As is clear from the above description, since the selection means for selecting the respective characteristic data M1, M2 is provided, the characteristic data M1, M2 can be switched, and the fuel injection control desired by the user can be performed. There is an effect that it is possible to easily respond to the condition in detail.

  By the way, the correction characteristic map (correction characteristic data) is not limited to one type as shown in FIG. 6, but is attached to each vehicle type on which the diesel engine 70 is mounted or to a work vehicle as shown in FIG. A plurality of types may be stored corresponding to each work machine (cultivator, plow, bucket, etc.). In the case of such a first alternative example, each of the correction characteristic maps M2 and M3 may be selected by a jumper pin provided in the ECU 11 or a selection switch provided in the cabin of the work vehicle. You may comprise so that the correction characteristic map M2, M3 corresponding to the said working machine may be selected by mounting | wearing a working machine with a working machine (Tiller, plow, bucket, etc.). Moreover, the structure which selects each characteristic map M2 and M3 with the control signal from this machine ECU (separate ECU) provided in the working vehicle may be sufficient.

  Needless to say, the correction characteristic data is not limited to the above-described map format M2, M3, function table, or the like. For example, instead of the above-described correction characteristic maps M2, M3, the torque limit stored in the purchase area U2 is used. It is also possible to employ the rate Dr as correction characteristic data (see FIGS. 9 and 10). In the case of the second alternative example, the control flow shown in FIG. 10 is basically the same as that in FIG. 7, but when calculating the target fuel injection amount R, the ECU 11 calculates the torque in the purchase area U2. The limit rate Dr is inquired, and an operation based on the rotational speed N and the throttle position, the output characteristic map M1, and the torque limit rate Dr is executed.

(4). Next, the overall structure of the diesel engine 70 will be described with reference to FIGS. The diesel engine 70 of the embodiment is of a four cylinder type, and an exhaust manifold 71 is disposed on the left side surface of the cylinder head 72 in the diesel engine 70. An intake manifold 73 is disposed on the right side surface of the cylinder head 72. The cylinder head 72 is mounted on a cylinder block 75 in which a crankshaft 74 and a piston (not shown) are built. Front and rear end portions of the crankshaft 74 are protruded from both front and rear side surfaces of the cylinder block 75, respectively. A cooling fan 76 is provided on the front side of the cylinder block 75. The rotational force is transmitted from the front end side of the crankshaft 74 to the cooling fan 76 via the V belt 77.

  As shown in FIGS. 11 to 14, a flywheel housing 78 is fixed to the rear surface of the cylinder block 75. A flywheel 79 is disposed in the flywheel housing 78. The flywheel 79 is pivotally supported on the rear end side of the crankshaft 74. The flywheel 79 is configured to rotate integrally with the crankshaft 74. The drive unit of the tractor 201 is configured to extract the power of the diesel engine 70 via the flywheel 79.

  An oil pan 81 is disposed on the lower surface of the cylinder block 75. Engine leg mounting portions 82 are respectively provided on the left and right side surfaces of the cylinder block 75 and the left and right side surfaces of the flywheel housing 78. Each engine leg mounting portion 82 is bolted to an engine leg 83 having vibration-proof rubber. The diesel engine 70 is supported in an anti-vibration manner on the engine support chassis 84 of the tractor 201 via the engine legs 83.

  As shown in FIGS. 11, 12, 14, and 16, an air cleaner (not shown) is provided on the inlet side of the intake manifold 73 via a collector 92 constituting an EGR device 91 (exhaust gas recirculation device). Connected. The outside air removed and purified by the air cleaner 88 is sent to the intake manifold 73 through the collector 92 of the EGR device 91 and supplied to each cylinder of the diesel engine 70.

  As shown in FIGS. 11, 12, 14, and 16, the EGR device 91 generates recirculated exhaust gas (EGR gas from the exhaust manifold 71) and fresh air (external air from the air cleaner) of the diesel engine 70. A collector (EGR main body case) 92 that is mixed and supplied to the intake manifold 73, a recirculation exhaust gas pipe 95 connected to the exhaust manifold 71 via an EGR cooler 94, and a collector 92 communicated with the recirculation exhaust gas pipe 95. EGR valve 96 is provided.

  With the above configuration, external air is supplied from the air cleaner into the collector 92, while EGR gas (a part of the exhaust gas discharged from the exhaust manifold 71) is supplied from the exhaust manifold 71 into the collector 92 through the EGR valve 96. To do. After the external air from the air cleaner and the EGR gas from the exhaust manifold 71 are mixed in the collector 92, the mixed gas in the collector 92 is supplied to the intake manifold 73. That is, a part of the exhaust gas discharged from the diesel engine 70 to the exhaust manifold 71 is recirculated from the intake manifold 73 to the diesel engine 70, so that the maximum combustion temperature during high load operation decreases, NOx (nitrogen oxide) emissions are reduced.

  As shown in FIGS. 11 and 13 to 16, the turbocharger 100 is attached to the left side surface of the cylinder head 72. The turbocharger 100 includes a turbine case 101 with a turbine wheel (not shown) and a compressor case 102 with a blower wheel (not shown). An exhaust manifold 71 is connected to the exhaust gas intake pipe 105 of the turbine case 101. Although illustration is omitted, a tail pipe is connected to the exhaust gas discharge pipe 103 of the turbine case 101 via a muffler or a diesel particulate filter. That is, the exhaust gas discharged from each cylinder of the diesel engine 70 to the exhaust manifold 71 is discharged from the tail pipe to the outside via the turbocharger 100 and the like.

  On the other hand, the air intake side of the air cleaner is connected to the air intake side of the compressor case 102 via the air supply pipe 104. An intake manifold 73 is connected to the supply / discharge side of the compressor case 102 via a supercharging pipe 108. In other words, the outside air removed by the air cleaner is supplied from the compressor case 102 to each cylinder of the diesel engine 70 through the supercharging pipe 108.

(5). Outline of Tractor Next, an outline of the tractor 201 on which the diesel engine 70 is mounted will be described with reference to FIGS. 17 and 18. A tractor 201 as a work vehicle supports a traveling machine body 202 with a pair of left and right rear wheels 204 as well as a pair of left and right front wheels 203. By driving the front wheel 203, it is configured to travel forward and backward.

  A diesel engine 70 mounted on the front portion of the traveling machine body 202 is covered with a bonnet 206. A cabin 207 is installed on the upper surface of the traveling machine body 202. Inside the cabin 207, a steering seat 208 on which an operator sits, and a steering handle 209 having a round handle shape as steering means positioned in front of the steering seat 208 are provided. Is provided. When the operator seated on the control seat 208 rotates the control handle 209, the steering angle (steering angle) of the left and right front wheels 203 changes according to the amount of operation. At the bottom of the cabin 207, a step 210 for an operator to board is provided. In the front column of the cabin 207, the ECU 11 (integrated ECU) is arranged.

  As shown in FIG. 17, the traveling aircraft body 202 includes an engine frame 214 having a front bumper 212 and a front axle case 213, and left and right aircraft frames 216 that are detachably connected to the rear portion of the engine frame 214 by fastening bolts. Composed. The front wheel 203 is attached via a front axle case 213 mounted so as to protrude outward from the outer surface of the engine frame 214. In addition, a transmission case 217 is connected to the rear part of the body frame 216 for appropriately shifting the output from the diesel engine 70 and transmitting the output to the rear wheel 204 (front wheel 203). The rear wheel 204 is attached to the mission case 217 via a rear axle case (not shown) mounted so as to protrude outward from the outer surface of the mission case 217.

  As shown in FIGS. 17 and 18, a hydraulic working machine lifting mechanism 220 for lifting and lowering a working machine (not shown) such as a tiller or a plow can be attached to and detached from the rear upper surface of the mission case 217. It is attached. The work machine is connected to the rear part of the mission case 217 via a lower link 221 and a top link 222 so as to be movable up and down. Further, a PTO shaft 223 for driving the work machine is provided on the rear side surface of the mission case 217.

  Although not shown in detail, the rotational power of the diesel engine 70 is transmitted from the rear surface side of the diesel engine 70 to the front surface side of the mission case 217 via the crankshaft 74, the flywheel 79, and the like. The rotational power of the diesel engine 70 is transmitted to the transmission case 217, and then the rotational power of the diesel engine 70 is appropriately shifted by the hydraulic continuously variable transmission or the traveling auxiliary transmission gear mechanism of the transmission case 217 to obtain a differential gear mechanism or the like. The driving force is transmitted from the mission case 217 to the rear wheel 204 via the transmission. In addition, the rotation of the diesel engine 70 that is appropriately shifted by the traveling auxiliary transmission gear mechanism is transmitted from the transmission case 217 to the front wheel 203 via the differential gear mechanism of the front axle case 213 and the like.

(6). Others The present invention is not limited to the above-described embodiment, and can be embodied in various forms. For example, the present invention is not limited to an engine control device for an engine mounted on a tractor, but can also be applied as an engine control device for an engine mounted on a farm work machine such as a combine or rice transplanter or a special work vehicle such as a wheel loader. is there. The fuel injection device is not limited to a common rail type, but may be an electronic governor type. In addition, the configuration of each unit is not limited to the illustrated embodiment, and various modifications can be made without departing from the spirit of the present invention.

M1 Output characteristic map M2, M3 Modified characteristic map N Rotational speed T Torque U1 Manufacturing side area U2 Purchasing side area 11 ECU (Integrated ECU)
14 Engine speed sensor (detection means)
16 Throttle position sensor (detection means)
20 storage means 20a correction characteristic area 70 diesel engine 115 injector 117 common rail system 120 common rail

Claims (2)

An engine, a fuel injection device that injects fuel into the engine, a detection unit that detects a driving state of the engine, detection information of the detection unit, and output characteristic data unique to the engine; An engine control device comprising an ECU for controlling operation,
The ECU is provided with a first area in which the output characteristic data is written, and a second area in which correction characteristic data for correcting the operation of the fuel injection device can be written, and the second area. Has a prohibition means to prohibit writing,
While the output characteristic data is written in the first area, the correction characteristic data is not written in the second area, and the engine is mounted on a work vehicle by the prohibiting means. The write prohibition state is released, and the correction characteristic data that matches the work characteristics of the work vehicle is written to the area.
Engine control device. The ECU in which the correction characteristic data is written is configured to alternatively inquire the correction characteristic data based on detection information of the detection means, and to operate the fuel injection device based on the inquiry result. Yes,
The engine control apparatus according to claim 1 .

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