JP5559908B2 - Engine control device - Google Patents

Description

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

  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 vehicle such as a tractor equipped with this type of engine, the ECU controls the operation of the common rail type fuel injection device based on output characteristic data such as a map format and a function table format, a rotation speed and a torque, for example, 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 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.

  In view of this, the present invention has a technical object to provide an engine control apparatus that solves the above-described problems.

The present invention includes an engine mounted on a work vehicle, 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 characteristics unique to the engine a in which the engine control system and a ECU which controls the operation of the fuel injector based on the data, the work vehicle, a correction means for correcting the output characteristic data, which can be mounted on the work vehicle Data storage means for storing a plurality of correction characteristic data corresponding to the type of work implement, and selection switch means for selecting one of the correction characteristic data , wherein the ECU comprises the selection switch means based on the selection operation, the correction characteristic data corresponding to the working machine attached to the work vehicle read from said data storage means, to the corrected characteristic data Hazuki calculates a correction result of the output characteristic data, and calculates the target fuel injection amount based on the detection information of the correction result and the detection means of the output characteristic data, is configured to actuate the fuel injector It is that.

In the engine control device, the data storage means as the correction means stores a torque limit rate for limiting torque with respect to a predetermined rotational speed in the output characteristic data, and the ECU is configured to control the torque limit rate based on the torque limit rate. The correction result of the output characteristic data may be calculated .

  According to a sixth aspect of the present invention, in the engine control apparatus according to any one of the first to fifth aspects, when the ECU does not respond to the correction means in a state where the wiring is connected to the correction means, It is configured to activate a notifying means for judging that the state is a failure and notifying the fact.

According to the present invention , an engine mounted on a work vehicle, 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 unique to the engine An engine control device comprising an ECU for controlling the operation of the fuel injection device based on characteristic data, and a type of work implement that can be mounted on the work vehicle as correction means for correcting the output characteristic data The ECU includes data storage means for storing a plurality of correction characteristic data corresponding to the data, and the ECU determines correction characteristic data to be read from the data storage means in accordance with the work implement mounted on the work vehicle. The correction result of the output characteristic data is calculated based on the correction characteristic data, and the correction result of the output characteristic data and the detection information of the detection means are calculated. Since it is configured to calculate a limit torque value and operate the fuel injection device in accordance with the limit torque value, the engine manufacturer is stored in the ECU if the engine model is the same. The output characteristic data can all be the same (common). Further, an engine purchase manufacturer who mounts the engine on a work vehicle can obtain the correction result that conforms to his / her specifications from the correction means. In other words, it becomes possible to select the optimum fuel injection control for each vehicle type on which the engine is mounted or for each work machine mounted on the work vehicle by the correction unit. Therefore, there is an effect that both the advantage of the engine manufacturer that improves the versatility of the ECU and the advantage of the engine purchase manufacturer that the compatibility of the ECU with the work vehicle is ensured.

  If the work machine is mounted on the work vehicle, the ECU can extract the correction characteristic data (for the work machine) suitable for the work machine. Therefore, the correction characteristic data for the work implement can be specified and selected accurately without bothering the operator. That is, it is possible to ensure the flexible setting of the ECU with respect to the fuel injection control, and it is possible to accurately execute the optimum fuel injection control for each work machine, for example, regardless of the skill level of the operator. .

In the engine control device, the data storage means as the correction means stores a torque limit rate for limiting torque with respect to a predetermined rotational speed in the output characteristic data, and the ECU is configured to control the torque limit rate based on the torque limit rate. Since the correction result of the output characteristic data is calculated, the droop characteristic of the corrected characteristic data by the correction of the engine purchase manufacturer can be maintained in a similar shape to the droop characteristic of the output characteristic data. The engine can be driven in a state close to the design concept. In addition, for engine purchasers, it is possible to execute fuel injection control that conforms to the company's specifications with a simple setting in which the correction characteristic data is set to the torque limiting rate, which requires time-consuming software design (correction). (Effect of characteristic data design) can be reduced.

In the engine control apparatus, a plurality of correction characteristic data is stored in the data storage means as the correction means, and the ECU is connected to the data storage means by a selection switch means provided in the work vehicle. determining a correction characteristic data to be read, that shall calculates a correction result of the output characteristic data based on the corrected characteristic data, the ECU will, by operation of said selection switch means, a working vehicle in which the engine is mounted Therefore, it is possible to select the optimum correction characteristic data. Therefore, the correction of the output characteristic data can be easily changed according to the work situation and the preference / request of the operator, and an effect is obtained that appropriate fuel injection control corresponding to the situation can be executed.

In the engine control device, manual operation means for variably setting a torque limiting rate for limiting torque with respect to a predetermined rotational speed in the output characteristic data is provided in the work vehicle, and the ECU is set by the manual operation means. A correction result of the output characteristic data is calculated based on the torque limit rate that has been set, a limit torque value is calculated based on the correction result of the output characteristic data and the detection information of the detection means, and the with shall be configured to actuate the fuel injection system, the ECU will, by operation of the manual operating unit, becomes possible to change and adjust to the optimum corrected characteristic data in the work vehicle in which the engine is mounted . Therefore, the correction of the output characteristic data can be changed stepwise or continuously according to the work situation and the preference / request of the operator, and it is possible to take a fine measure for the fuel injection control.

In the engine control device, the ECU, when not detecting the correcting means, be shall be configured to activate the fuel injector based on the detected information and the output characteristic data of said detecting means Thus, even if a failure such as a failure or malfunction of the correction means occurs and the correction means cannot be detected, the fail-safe function using the output characteristic data will work. Therefore, it is possible to avoid the situation where the ECU malfunctions or stops or the engine malfunctions or stops.

In the engine control apparatus, when the ECU is not connected to the correction unit and the correction unit does not respond, the ECU operates a notification unit that determines that a failure has occurred and notifies the fact of the failure. with shall be configured, for example, the correction means does not store the modified characteristic data, accidentally or when connected to the ECU in the case of disconnection between the ECU and the correction means has occurred The fact is grasped by the operation of the notification means. Therefore, it is possible to avoid the possibility of forgetting to store the correction characteristic data in the correction means or overlooking the disconnection in the connection line.

By the way, work vehicles that are not equipped with work implements are assumed to be in a state in which normal travel such as road travel is performed without performing various operations such as farm work, so that correction characteristic data that suits the work characteristics However, it is sufficient to control the fuel injection using the output characteristic data originally provided. In this respect, the engine control device, when not wearing a working machine in the working vehicle, to actuate the fuel injector based on the detected information and the output characteristic data of said detecting means, for configuring the ECU As an example, there is an effect that it is possible to easily execute efficient fuel injection control in accordance with whether or not the work implement is mounted (work vehicle use state) without performing a fine setting operation or the like.

It is a conceptual explanatory drawing which summarized 1st Embodiment. 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 fuel injection control. It is a conceptual explanatory view summarizing the second embodiment. It is fuel system explanatory drawing of a diesel engine. It is explanatory drawing which shows the relationship between a rotational speed and a torque. It is a conceptual explanatory drawing which summarized 3rd Embodiment. It is explanatory drawing which shows the relationship between a rotational speed and a torque. It is a flowchart of fuel injection control. It is explanatory drawing which shows the relationship between the rotational speed and torque in another example. It is explanatory drawing at the time of changing a rotation speed limit value during an engine drive, (a) is a case where droop characteristic is not changed, (b) is a case where droop characteristic is also changed. It is a conceptual explanatory drawing which summarized 4th Embodiment. It is fuel system explanatory drawing of a diesel engine. Conceptual explanatory diagram summarizing the fifth embodiment It is fuel system explanatory drawing of a diesel engine. It is an external appearance perspective view of a diesel engine. It is a side view of a tractor.

  Hereinafter, an embodiment embodying the present invention will be described with reference to the drawings when applied to a diesel engine mounted on a tractor as a vehicle.

(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 to FIGS. 3 and 18. As shown in FIGS. 3 and 18, a fuel tank 118 is connected to the injectors 115 for four cylinders 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 FIGS. 3 and 18, 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 FIGS. 3 and 18, 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 according to the first embodiment will be described with reference to FIGS. 1 to 6. As shown in FIG. 3, the ECU 11 includes an ECU 11 that operates the fuel injection valve 119 of each cylinder in the diesel engine 70. 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.

  At the output side of the ECU 11, electromagnetic solenoids of the fuel injection valves 119 for at least four cylinders are respectively connected. 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. Further, a notification means 27 such as an alarm buzzer or an alarm lamp is also connected to the output side of the ECU 11.

  In the storage means (flash memory or EEPROM) provided in 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. It is remembered. 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 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 as a target fuel. The fuel injection control is performed such that the injection amount R is calculated and the common rail system 117 is operated based on the calculation result. 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.

  Each embodiment of the present invention includes a correction unit that corrects the output characteristic map M1. The ECU 11 corrects the output characteristic map M1 corrected by the correction unit and the detected values of the engine speed sensor 14 and the throttle position sensor 16. It is possible to calculate a limit torque value based on this and operate the common rail system 117 according to the limit torque value. In the first embodiment shown in FIGS. 1 to 5, a work machine ECU 21 that is a data storage unit is employed as an example of a correction unit.

  The work machine ECU 21 as data storage means is electrically connected to the ECU 11 of the first embodiment via a CAN communication bus 23 (see FIGS. 2 and 3). The work machine ECU 21 has a function of controlling the drive of a work machine (cultivator, plow, bucket, etc.) mounted on the work vehicle. Like the ECU 11, the work machine ECU 21 includes a CPU, an EEPROM, a flash memory, a RAM, a CAN controller, an input / output interface, and the like, and can be disposed at any location of the work machine. Of course, it is also possible to arrange the ECU 11 together with the diesel engine 70 or the main body of the work vehicle. The CAN communication bus 23 is a communication line for data communication using a CAN (controller area network) protocol. As is clear from this point, the CAN communication environment is applied to the ECU 11 and the work machine ECU 21. Data communication based on the CAN communication protocol is an extension of the LAN communication environment. The CAN communication protocol is a differential two-wire having a common return (an instruction to return a program that has moved to a subroutine or interrupt routine to the main routine). A serial communication protocol that uses a bus line to maintain distributed real-time control and multiplexing.

  The storage means (flash memory or EEPROM) of the work machine ECU 21 stores in advance a correction characteristic map M2 (see FIG. 5) as correction characteristic data for correcting the operation of the common rail system 117. The correction characteristic map M2 shows 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 work machine ECU 21 is different from each vehicle type on which the diesel engine 70 is mounted or to a work machine (cultivator or plow, Can be set for each bucket). 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.

  In the first embodiment, the ECU 11 to which the work machine ECU 21 is connected calculates the torque T based on the detection values of the engine speed sensor 14 and the throttle position sensor 16, the output characteristic map M1, and the correction characteristic map M2, and thereby achieves the target. The fuel injection amount R is obtained, and the common rail system 117 is operated based on the calculation result (so as to limit the torque T with respect to the predetermined rotational speed N) (see FIGS. 1 and 2). 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).

  Whether the ECU 11 reads and refers to the correction characteristic map M2 from the work machine ECU 21 according to the setting of the identification means 25 associated with the correction characteristic map M2 (uses the correction characteristic map M2 for correction of the output characteristic map M1). Whether or not) is determined. The identification means 25 may be configured to determine whether or not to use the correction characteristic map M2 by setting a jumper pin provided in the ECU 11 or setting a terminal of a coupler connected from the work machine ECU 21 to the ECU 11. The ECU 11 of the first embodiment calculates the target fuel injection amount R that is torque-limited using both the characteristic maps M1 and M2 when the work implement ECU 21 is connected to the ECU 11 and there is a response, and is not connected? Alternatively, when there is no response, the target fuel injection amount R is set to be calculated using the output characteristic map M1. That is, the connection of the work machine ECU 21 to the ECU 11 and the presence or absence of a response function as the identification unit 25. The state in which the work machine ECU 21 is not connected corresponds to “when no correction means is detected”, for example, when the work machine is not attached to the work vehicle, or when the work machine ECU 21 is not connected to the ECU 11. It is done. The state where there is no response from the work machine ECU 21 may be, for example, a case where the correction characteristic map M2 is not stored in the work machine ECU 21, or a case where communication is impossible.

  As shown in FIGS. 1 and 2, the engine control apparatus of the embodiment is shipped from an engine manufacturer with an output characteristic map M1 written in the ECU 11. When the engine purchasing manufacturer mounts the diesel engine 70 on the work vehicle, the work machine ECU 21 storing the correction characteristic map M2 is connected to the ECU 11 via the CAN communication bus 23.

  Hereinafter, an example of the fuel injection control in the first embodiment will be described with reference to the flowchart of FIG. As described above, since the ECU 11 of the first embodiment is connected to the work implement ECU 21, it is based on the detection values of the engine speed sensor 14 and the throttle position sensor 16, the output characteristic map M1, and the correction characteristic map M2. The target fuel injection amount R is calculated by calculating the torque T, and the common rail system 117 is operated based on the calculation result (so as to limit the torque T with respect to the predetermined rotational speed N). In this case, as shown in the flowchart of FIG. 6, the ECU 11 determines whether or not the work machine ECU 21 is connected (whether there is a wiring with the work machine ECU 2) (step S1). If the work implement ECU 21 is not connected (S1: NO), the detection values of the engine speed sensor 14 and the throttle position sensor 16 are read at a predetermined timing (appropriately every time) (step S2). With reference to the output characteristic map M1, 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 S1 to continue the fuel injection control.

  If work implement ECU21 is connected in step S1 (S1: YES), ECU11 will discriminate | determine the presence or absence of the response of work implement ECU21 (step S5). If there is no response from the work implement ECU 21 (S5: NO), the ECU 11 determines that the state is a failure and activates the notification means 27 (step S6) to notify the operator that the fuel injection control is in a state of failure. Arouse. And it transfers to step S2 and performs the fuel-injection control using the output characteristic map M1.

  If a response of the work implement ECU 21 is detected in step S5 (S5: YES), the detection values of the engine speed sensor 14 and the throttle position sensor 16 are read at a predetermined timing (appropriately every time) (step S7). The ECU 11 refers to the output characteristic map M1 and the correction characteristic map M2 in the work machine ECU 21 to obtain the torque T from the rotation speed N and the throttle position read earlier, and the target fuel injection amount (torque limited). R is calculated (step S8). Then, the common rail system 117 is operated based on the target fuel injection amount R whose torque is limited (step S9). Thereafter, if the key switch for power supply (not shown) is turned on, the process returns to step S1 to continue the fuel injection control.

  As is apparent from the above description and FIGS. 1 to 6, the engine 70 mounted on the work vehicle, the fuel injection device 117 that injects fuel into the engine 70, and detection means that detects the driving state of the engine 70. 14 and 16, and 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, The ECU 11 includes a correction unit 21 that corrects the output characteristic data M1, and the ECU 11 limits the torque limit value based on the correction result of the output characteristic data M1 by the correction unit 21 and the detection information of the detection units 14 and 16. And the fuel injection device 117 is operated according to the limit torque value. , If the type of the engine 70 are the same, it is the output characteristic data M1 stored in the ECU11 to those either identical (common). Further, an engine purchase manufacturer who mounts the engine 70 on a work vehicle can obtain the correction result that conforms to his / her specifications from the correction means 21. In other words, the correction means 21 can select optimal fuel injection control for each vehicle type on which the engine 70 is mounted and for each work machine mounted on the work vehicle. Therefore, there is an effect that both the advantage of the engine manufacturer that improves the versatility of the ECU 11 and the advantage of the engine purchase manufacturer that the compatibility of the ECU 11 with respect to the work vehicle can be achieved.

  As apparent from the above description and FIGS. 1 to 6, the data storage means 21 as the correction means stores correction characteristic data M2 for correcting the operation of the fuel injection device 117, and The ECU 11 calculates the correction result of the output characteristic data M1 based on the correction characteristic data M2 in response to the setting of the identification means 25 associated with the correction characteristic data M2. Therefore, the ECU 11 sets the identification means 25. If so, the output characteristic data M1 is corrected using the corrected characteristic data M2, and the torque of the engine 70 can be limited based on the correction result. Therefore, there is an effect that the fuel injection control corrected according to the specifications of the engine purchase manufacturer can be executed without bothering the operator (without depending on the proficiency level or the like).

  As is apparent from the above description and FIG. 6, when the ECU 11 does not detect the correction unit 21, the fuel injection device 117 is based on the detection information of the detection units 14 and 16 and the output characteristic data M1. Since, for example, a failure such as a failure or malfunction of the correction means 21 occurs and the correction means 21 cannot be detected, a fail-safe function using the output characteristic data M1 is used. Will work. Therefore, it is possible to avoid the situation where the ECU 11 malfunctions or stops, or the engine 70 malfunctions or stops.

  As is clear from the above description and FIG. 6, the ECU 11 determines that a failure has occurred and notifies the failure when there is no response from the correction means 21 when the wiring is connected to the correction means 21. For example, when the correction means 21 that does not contain the correction characteristic data M2 is mistakenly connected to the ECU 11, or between the ECU 11 and the correction means 21, the notification means 27 is operated. When the disconnection occurs, the fact is grasped by the operation of the notification means 27. Therefore, it is possible to avoid the possibility of forgetting to store the correction characteristic data M2 in the correction means 21 or overlooking the disconnection in the wiring.

  Incidentally, the determination in step S1 shown in FIG. 6, that is, the determination of whether or not the work machine ECU 21 is connected is common to the determination of whether or not the work machine is mounted on the work vehicle. Since the work vehicle not equipped with the work machine is assumed to be in a state in which a normal traveling such as a road traveling is performed without performing various operations such as farm work, a correction characteristic map M2 that matches the work characteristics is provided. It is not necessary to dare to use it, and it is sufficient to perform fuel injection control using the output characteristic map M1 originally provided. Therefore, as shown in steps S1 to S4 in FIG. 6, when the work machine is not mounted on the work vehicle, the ECU 11 is based on the detected values of the engine speed sensor 14 and the throttle position sensor 16 and the output characteristic map M1. The common rail system 117 is activated. Therefore, it is possible to easily execute efficient fuel injection control according to whether or not the work implement is mounted (use condition of the work vehicle) without performing a fine setting operation or the like.

(3). Next, fuel injection control of the common rail 120 according to the second embodiment will be described with reference to FIGS. 7 to 9. Here, in the second embodiment and subsequent embodiments, the same reference numerals as those in the first embodiment are given to the components that are the same as those in the first embodiment, and the detailed description thereof is omitted.

  Now, the correction characteristic data for correcting the operation of the common rail system 117 is not limited to one type as shown in FIG. 5, but for each vehicle type on which the diesel engine 70 is mounted or a work machine mounted on the work vehicle ( A plurality of types may be stored corresponding to each (cultivator, plow, bucket, etc.) (see FIG. 9). In the second embodiment, a plurality of types of correction characteristic maps M2 and M3 are stored in the work machine ECU 21 as data storage means. In this case, each of the correction characteristic maps M2 and M3 may be selected by using, for example, a jumper pin provided in the ECU 11 or a selection switch provided in the cabin of the work vehicle. Moreover, the structure which each characteristic map M2 and M3 may be selected with the control signal from another ECU (work machine ECU21 in this case) in the work vehicle side may be sufficient.

  In the second embodiment, it is configured to select the correction characteristic maps M2 and M3 corresponding to the work machine by mounting the work machine on the work vehicle (see FIGS. 7 and 8). For example, when a discrimination button for each work implement is arranged on the vehicle side hitch provided at the rear of the work vehicle and the work implement side hitch is connected to the vehicle hitch, the discrimination button corresponding to the work implement is set by connection. What is necessary is just to comprise. Here, assuming that the corrected characteristic map M2 is for the rotary tiller and the corrected characteristic map M3 is for the plow, when the rotary tiller is attached, the discriminating button for the tiller is set, In order to correct the output characteristic map M1, the ECU 11 refers to the correction characteristic map M2 for the rotary tiller. When the plow is attached, the plow discrimination button is set, and the ECU 11 refers to the plow correction characteristic map M3 in order to correct the output characteristic map M1.

  The ECU 11 of the second embodiment determines a correction characteristic map M2 or M3 to be read from the work implement ECU 21 according to the work implement mounted on the work vehicle, and the correction result of the output characteristic map M1 based on the correction characteristic map M2 or M3. Is calculated. Then, based on the correction result of the output characteristic map M1 and the detection values of the engine speed sensor 14 and the throttle position sensor 16, the torque T is calculated to obtain the target fuel injection amount R. Based on the calculation result (predetermined rotational speed) The common rail system 117 is activated (to limit the torque T to N).

  As apparent from the above description and FIGS. 7 to 9, the data storage means 21 as the correction means includes a plurality of correction characteristic data M <b> 2 and M <b> 3 according to the type of work equipment that can be mounted on the work vehicle. The ECU 11 determines the correction characteristic data M2 or M3 to be read from the data storage means 21 according to the work implement mounted on the work vehicle, and based on the correction characteristic data M2 or M3 Since the correction result of the output characteristic data M1 is calculated, if the work machine is mounted on the work vehicle, the ECU 11 can be used to correct the correction characteristic data M2 suitable for the work machine (for the work machine) or M3 can be extracted. Therefore, the correction characteristic data M2 or M3 for the work implement can be specified and selected accurately without bothering the operator. That is, while the flexible setting of the ECU 11 with respect to the fuel injection control can be ensured, for example, the optimum fuel injection control for each work implement can be accurately executed without depending on the skill level of the operator or the like. .

(4). Next, fuel injection control of the common rail 120 according to the third embodiment will be described with reference to FIGS. 10 to 12. As described above, it goes without saying that the correction characteristic data is not limited to the map format M2, M3 or the function table. For example, instead of the correction characteristic map M2, M3, the correction characteristic data is stored in the work machine ECU 21 (data storage means). It is also possible to employ the torque limit rate Dr that has been set as the correction characteristic data (see FIGS. 10 to 12). In the case of the third embodiment, the control flow shown in FIG. 12 is basically the same as that in FIG. 6, but when calculating the target fuel injection amount R, the ECU 11 refers to the torque limit rate Dr in the work implement ECU 21. Thus, the calculation based on the rotational speed N and the throttle position, the output characteristic map M1, and the torque limit rate Dr is executed.

  As apparent from the above description and FIGS. 10 to 12, the data storage means 21 as the correction means stores a torque limiting rate Dr for limiting the torque T with respect to a predetermined rotational speed N in the output characteristic data M1. Since the ECU 11 calculates the correction result of the output characteristic data M1 based on the torque limiting rate Dr, the ECU 11 calculates the droop characteristic of the corrected characteristic data by the correction of the engine purchase manufacturer as the droop characteristic of the output characteristic data M1. The engine 70 can be driven in a state close to its own design concept for the engine manufacturer. In addition, it is possible for an engine purchase manufacturer to execute fuel injection control that conforms to the company's specifications with a simple setting in which the correction characteristic data is set to the torque limiting rate Dr. This has the effect of reducing the burden of design of modified characteristic data.

  Furthermore, as another example of the third embodiment, the rotation speed limit value Lt stored in the work machine ECU 21 can be employed as the correction characteristic data (see FIG. 13). In such another example, when calculating the target fuel injection amount R, the ECU 11 refers to the rotation speed limit value Lt in the work machine ECU 21, and the rotation speed N, the throttle position, the output characteristic map M1, Calculation based on the rotation speed limit value Lt is executed. In FIG. 13, the solid line Tmx4 indicates the maximum torque line (droop characteristic) when the rotation speed set value Lt is set. It is also possible to change the droop characteristics Tmx5 to Tmx7 shown in FIG. 13 by sending not only the rotation speed limit value Lt but also a confirmation signal for changing the droop characteristics to the ECU 11. That is, variations of the droop characteristic based on the rotation speed limit value Lt can be easily set, and it becomes easy to cope with various fuel injection control settings.

  In another example of the third embodiment, when the ECU 11 determines that the rotational speed limit value Lt is stored in the work machine ECU 21 when the diesel engine 70 is started, the rotational speed limit value Lt is immediately set. The common rail system 117 can be configured to operate by calculating the target fuel injection amount R.

  Further, a variable resistor type rotational speed limit switch (not shown) is adopted as the correction means, and the rotational speed limit value Lt is changed stepwise or continuously by a knob operation of the rotational speed limit switch, thereby correcting the characteristic map. You may comprise so that droop characteristic of (correction result) may be changed and adjusted.

  For example, when the operator operates the rotational speed limit switch while the diesel engine 70 is being driven, the droop characteristic Tmx9 based on the rotational speed limit value Lt2 after the operation is the rotational speed before the operation, as shown in FIG. Compared with the droop characteristic Tmx8 based on the limit value Lt1, when it moves to the upper side (outside) as a whole, the target fuel injection amount R is immediately calculated using the rotational speed limit value Lt2 (droop characteristic Tmx9), and the common rail system. 117 is preferably activated.

  On the other hand, in other cases, for example, as shown in FIG. 14B, the droop characteristic Tmx11 based on the rotational speed limit value Lt4 after the operation partially intersects with the droop characteristic Tmx10 based on the rotational speed limit value Lt3 before the operation. When doing so, it is preferable to calculate the difference and gradually approach the rotational speed limit value Lt4 (droop characteristic Tmx11), and finally calculate the rotational speed limit value Lt4. This is because the diesel engine 70 may suddenly stop due to the droop characteristic change under the condition that the upper limit of the droop characteristic is lowered by the operation of the rotation speed limit switch (see the area Ar in FIG. 14B). It is a measure to prevent.

(5). Next, fuel injection control of the common rail 120 in the fourth embodiment will be described with reference to FIGS. 15 and 16. In the fourth embodiment, similarly to the second embodiment, a plurality of types of correction characteristic maps M2 and M3 shown in FIG. 9 are stored in the work machine ECU 21 as data storage means. In this case, operation buttons 28a and 28b associated with the respective correction characteristic maps M2 and M3 are provided as selection switch means in the cabin of the work vehicle (see FIGS. 15 and 16). By the selection operation of these operation buttons 28a and 28b, the correction characteristic map M2 or M3 to be read from the work machine ECU 21 is selected. Each push button 28a, 28b is locked when it is pressed once, causing the ECU 11 to select the corresponding correction characteristic map M2, M3, and when it is pressed again, it returns to the original state and the selection by the ECU 11 is released. It is a switch. Each operation button 28a, 28b is connected to the input side of the ECU 11 (see FIG. 16).

  The ECU 11 of the fourth embodiment determines a correction characteristic map M2 or M3 to be read from the work implement ECU 21 by selecting each of the operation buttons 28a and 28b as selection switch means, and an output characteristic map based on the correction characteristic map M2 or M3. The correction result of M1 is calculated. Then, based on the correction result of the output characteristic map M1 and the detection values of the engine speed sensor 14 and the throttle position sensor 16, the torque T is calculated to obtain the target fuel injection amount R. Based on the calculation result (predetermined rotational speed) The common rail system 117 is activated (to limit the torque T to N).

  As apparent from the above description and FIGS. 15 and 16, the data storage means 21 as the correction means stores a plurality of correction characteristic data M2 and M3, and the ECU 11 is provided in the work vehicle. The selected selection means 28a, 28b determines the correction characteristic data M2, M3 to be read from the data storage means 21, and calculates the correction result of the output characteristic data M1 based on the correction characteristic data M2, M3. The ECU 11 can select the optimum correction characteristic data for the work vehicle on which the engine 70 is mounted by operating the selection switch means 28a and 28b. Accordingly, the correction of the output characteristic data M1 can be easily changed according to the work situation and the preference / request of the operator, and there is an effect that appropriate fuel injection control can be executed according to the situation.

(6). Next, fuel injection control of the common rail 120 according to the fifth embodiment will be described with reference to FIGS. 17 and 18. In the fifth embodiment, similarly to the third embodiment, the torque limiting rate Dr is adopted as the correction characteristic data, and the ECU 11 is configured to calculate the correction result of the output characteristic data M1 based on the torque limiting rate Dr. . However, in the fifth embodiment, the data storage means is not provided, and the variable resistor type volume switch 29 capable of changing the position of the knob continuously or stepwise is used as a correction means (manual operation means). In the cabin. In this case, the value of the torque limiting rate Dr is changed stepwise or continuously by the knob operation of the volume switch 29, and is proportional to the torque limiting rate Dr while maintaining the similar shape of the droop characteristic of the output characteristic map M1. The droop characteristic of the correction characteristic map (correction result) is changed and adjusted. The volume switch 29 of the fifth embodiment is connected to the input side of the ECU 11 via the A / D converter 30 (see FIG. 18). In calculating the target fuel injection amount R, the ECU 11 refers to the torque limit rate Dr corresponding to the knob operation amount of the volume switch 29, refers to the rotational speed N, the throttle position, the output characteristic map M1, and the torque limit rate Dr. An operation based on and is executed.

  As apparent from the above description and FIGS. 17 and 18, the correction means is a manual operation means 29 provided in the work vehicle, and the manual operation means 29 is a predetermined rotational speed in the output characteristic data M1. Since the torque limit rate Dr that limits the torque T with respect to N is configured to be variably set, the ECU 11 is optimally corrected for the work vehicle on which the engine 70 is mounted by operating the manual operation means 29. It can be changed and adjusted to the characteristic data. Therefore, the correction of the output characteristic data M1 can be changed stepwise or continuously in accordance with the work situation and the preference / request of the operator, and it is possible to take a fine measure for the fuel injection control.

(7). Summary As is apparent from the above description, according to the present invention, the engine 70 mounted on the work vehicle, the fuel injection device 117 that injects fuel into the engine 70, and the detection means that detects the driving state of the engine 70. 14 and 16, and 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, The ECU 11 includes correction means 21 and 29 for correcting the output characteristic data M1, and the ECU 11 includes a correction result of the output characteristic data M1 by the correction means 21 and 29 and detection information of the detection means 14 and 16. Since the limit torque value is calculated based on the limit torque value, the fuel injection device 117 is operated according to the limit torque value. As long as the model of the engine 70 is the same, the engine manufacturer can make the output characteristic data M1 stored in the ECU 11 the same (common). In addition, an engine purchase manufacturer that mounts the engine 70 on a work vehicle can obtain the correction results that match the specifications of the company from the correction means 21 and 29. In other words, the correction means 21 can select optimal fuel injection control for each vehicle type on which the engine 70 is mounted and for each work machine mounted on the work vehicle. Therefore, there is an effect that both the advantage of the engine manufacturer that improves the versatility of the ECU 11 and the advantage of the engine purchase manufacturer that the compatibility of the ECU 11 with respect to the work vehicle can be achieved.

(8). Next, the overall structure of the diesel engine 70 will be described with reference to FIG. The diesel engine 70 of the embodiment is of a four cylinder type, and an exhaust manifold (not shown) 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 and a piston (not shown) are built. The front and rear front ends of the crankshaft protrude from the 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.

  A flywheel housing 78 is fixed to the rear surface of the cylinder block 75. A flywheel (not shown) is disposed in the flywheel housing 78. The flywheel is pivotally supported on the rear end side of the crankshaft, and is configured to rotate integrally with the crankshaft. It is comprised so that the motive power of the diesel engine 70 may be taken out to the drive part of a work vehicle via a flywheel. 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. An engine leg (not shown) having a vibration proof rubber is bolted to each engine leg mounting portion 82. The diesel engine 70 is supported in an anti-vibration manner on the engine support chassis 84 of the tractor 201 via each engine leg.

  An air cleaner (not shown) is connected to the inlet side of the intake manifold 73 via a collector 92 constituting an EGR device 91 (exhaust gas recirculation device). 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. The EGR device 91 mixes the recirculated exhaust gas (EGR gas from the exhaust manifold 71) of the diesel engine 70 and fresh air (external air from the air cleaner) and supplies the mixture to the intake manifold 73 (EGR main body case) 92. A recirculation exhaust gas pipe 95 connected to the exhaust manifold 71 via an EGR cooler 94, and an EGR valve 96 communicating the collector 92 with the recirculation exhaust gas pipe 95.

  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.

  A 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 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.

  A fuel tank 118 (see FIG. 3) is connected to the injectors 115 for four cylinders 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. 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. A common rail 120 is connected to the discharge side of the fuel supply pump 116 via a high-pressure pipe 123.

(9). Outline of Tractor Next, an outline of a tractor 201 as a work vehicle on which the diesel engine 70 is mounted will be described with reference to FIG. The tractor 201 supports the 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, and the rear wheel 204 and the front wheels 203 are supported by a diesel engine 70 mounted on the front part of the traveling machine body 202. By driving, 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. The ECU 11 is disposed in the front column of the cabin 207.

  The traveling machine body 202 includes an engine frame 214 having a front bumper 212 and a front axle case 213, and left and right machine body frames 216 that are detachably connected to the rear portion of the engine frame 214 by fastening bolts. 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.

  On the rear upper surface of the transmission case 217, a hydraulic working machine lifting mechanism 220 for lifting and lowering a working machine (not shown) such as a tiller or a plow is detachably attached. The work machine is connected to the rear part of the mission case 217 via a lower link (not shown) 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, 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 transmission case 217 via a crankshaft, a flywheel, 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.

(10). 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. . The fuel injection device is not limited to a common rail type, but may be an electronic governor type. The communication bus is not limited to the CAN communication bus, but may be another communication bus such as a LAN communication bus. The data storage means as the correction means may be external storage means such as a flash memory or a hard disk as long as the data storage means is separate from the ECU 11. 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 characteristics map (output characteristics data)
M2, M3 correction characteristic map (correction characteristic data)
N Rotational speed T Torque 11 ECU
14 Engine speed sensor (detection means)
16 Throttle position sensor (detection means)
21 Work implement ECU (data storage means)
23 CAN communication bus 25 Identification means 27 Notification means 28a, 28b Operation buttons (selection switch means)
29 Manual operation means (volume switch)
70 Diesel engine 115 Injector 117 Common rail system 120 Common rail

Claims (3)

Based on an engine mounted on a work vehicle, 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 And an ECU for controlling the operation of the fuel injection device,
The working vehicle, as the correction means for correcting the output characteristic data, and data storage means for storing a plurality of modification characteristic data corresponding to the type of wearable working machine to the working vehicle, of the modified characteristics data temporary Selection switch means for selecting one, and
The ECU is based on the selection operation of said selection switch means, the correction characteristic data corresponding to the working machine attached to the work vehicle read from said data storage means, the correction of the output characteristic data based on the corrected characteristic data A result is calculated, a target fuel injection amount is calculated based on a correction result of the output characteristic data and detection information of the detection means, and the fuel injection device is operated;
Engine control device. The data storage means as the correction means stores, as the correction characteristic data, a torque limiting rate for limiting torque with respect to a predetermined rotational speed in the output characteristic data, and the ECU performs the output based on the torque limiting rate. Calculate the correction result of the characteristic data,
The engine control apparatus according to claim 1.   The data storage means as the correction means stores a rotational speed limit value as the correction characteristic data, and the ECU calculates a correction result of the output characteristic data based on the rotational speed limit value.
The engine control apparatus according to claim 1.

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