JP5998959B2 - Fuel injection control system - Google Patents

Description

  The present invention relates to a fuel injection control system that controls fuel injection to an internal combustion engine.

  2. Description of the Related Art Conventionally, as a fuel injection control system for controlling fuel injection into an engine mounted on a vehicle, an electronic control device (hereinafter referred to as ECU) for controlling an injector and an electronic drive device for driving the injector in accordance with an injection request signal from the ECU (Hereinafter referred to as EDU) is known (for example, see Patent Document 1).

  In the fuel injection control system configured as described above, an injection request signal for each cylinder is output from the ECU to the EDU, and the EDU drives the injector of each cylinder in response to the injection request signal. Since the injection request signal is a pulse signal, the ECU can control the injection start timing and the injection time of the injector by switching the injection request signal between a high level and a low level.

  In the fuel injection control system described above, setting data for setting the injection characteristics of the injector is transmitted from the ECU to the EDU separately from the injection request signal, and the EDU determines the injection characteristics of the injector according to the setting data. Change.

JP 2009-5518 A

  The rest time (hereinafter referred to as the interval between injections) from the end of fuel injection to a certain cylinder (hereinafter referred to as the previous injection cylinder) to the start of fuel injection for the next cylinder (hereinafter referred to as the current injection cylinder) is: It changes according to the operating state of the engine. For example, the interval between injections becomes shorter as the engine speed increases.

  In order to change the injection characteristic of the injector between the fuel injection for the previous injection cylinder and the fuel injection for the current injection cylinder, the fuel injection to the previous injection cylinder is performed. Immediately after the completion, new setting data needs to be transmitted from the ECU to the EDU.

  However, if the interval between injections is shortened, there is a possibility that fuel injection to the current injection cylinder may be started before transmission of new setting data is completed. If transmission of the setting data is completed during the fuel injection to the injection cylinder this time, the injection characteristics of the injector will change during the fuel injection, which may adversely affect the exhaust emission. It was.

  The present invention has been made in view of these problems, and an object thereof is to suppress the occurrence of a situation in which the injection characteristics of an injector change during fuel injection.

Fuel injection control system has been proposed in order to achieve the above object, a start timing and the injection time of the fuel injection for each of the fuel injection valve for injecting fuel into the cylinder provided in each of the plurality of cylinders of the internal combustion engine A control device for controlling the fuel injection valve by transmitting injection characteristic setting data for setting the injection characteristic of the fuel injection valve, and an injection request signal and injection characteristic obtained from the control device And a drive device for driving the fuel injection valve according to the setting data.

  In the fuel injection control system configured as described above, by obtaining the injection request signal from the control device, the drive device performs the fuel injection valve for each of the plurality of cylinders at the start timing and the injection time according to the injection request signal. The fuel injection valve is driven with the injection characteristic according to the injection characteristic setting data by acquiring the injection characteristic setting data from the control device.

  In the control device, the interval measuring means uses one of the plurality of cylinders as a first cylinder and one cylinder different from the first cylinder as a second cylinder, and a fuel injection valve corresponding to the first cylinder. Measuring the interval between injections, which is the period from when the fuel injection to the second cylinder starts until the fuel injection valve corresponding to the second cylinder starts fuel injection to the second cylinder, When the setting data transmission time, which is the time required for transmitting the injection characteristic setting data to the driving device, is longer than the interval between injections, the transmission of the injection characteristic setting data is prohibited.

  As a result, the fuel injection valve corresponding to the first cylinder starts transmitting the injection characteristic setting data after the fuel injection valve corresponding to the first cylinder finishes the fuel injection to the first cylinder, and the fuel injection valve corresponding to the second cylinder is transmitted to the second cylinder. If it is predicted that the transmission of the injection characteristic setting data will be completed during the fuel injection, the injection characteristic setting data is not transmitted.

  For this reason, the transmission of the injection characteristic setting data is completed during the fuel injection to the second cylinder, and the injection characteristic changes during the fuel injection to the second cylinder. Can be suppressed.

1 is a block diagram showing a configuration of a fuel injection control system 1. FIG. It is a timing chart which shows the measuring method of interval between injection Ti. It is a flowchart which shows a communication status determination process. It is a figure explaining the ring buffer structure of a communication command.

Embodiments of the present invention will be described below with reference to the drawings.
The fuel injection control system 1 of this embodiment is mounted on a vehicle, and as shown in FIG. 1, each cylinder # 1, # 2, # 3, # 4, # 5 of an engine 100 (diesel engine in this embodiment). , # 6, # 7, and # 8 (not shown), injectors 101, 102, 103, 104, 105, 106, 107, and 108 are driven to control fuel injection into engine 100.

  A fuel injection control system 1 includes an electronic control unit (Electronic Control Unit) 2 (hereinafter referred to as an engine ECU 2) that performs various processes for controlling the engine 100, and injectors 101 to 108 in accordance with a drive request from the engine ECU 2. An electronic driver unit (Electronic Driver Unit) 3 (hereinafter referred to as EDU 3) is provided.

  The engine ECU 2 is configured around a well-known microcomputer 10 (hereinafter referred to as a microcomputer 10) including a CPU, ROM, RAM, I / O and a bus line connecting these components, and is stored in the ROM. Various processes are executed based on the program.

  The EDU 3 includes a drive circuit 20 that drives the injectors 101, 104, 106, and 107, and a drive circuit 30 that drives the injectors 102, 103, 105, and 108. That is, the injectors 101 to 108 for all eight cylinders are divided into two systems of four cylinders, and the injectors 101, 104, 106, and 107 of cylinders # 1, # 4, # 6, and # 7 are set as the first system. The injectors 102, 103, 105, 108 of cylinders # 2, # 3, # 5, and # 8 are the second system. The fuel injection order of each cylinder # 1 to # 8 is “# 1 → # 2 → # 7 → # 3 → # 4 → # 5 → # 6 → # 8”.

  The injectors 101 to 108 are constituted by electromagnetic solenoids. When the drive circuits 20 and 30 are energized, the injectors 101 are opened to perform fuel injection. When the drive circuits 20 and 30 are de-energized, the injectors 101 to 108 are closed. Stop fuel injection.

  The EDU 3 is connected to the engine ECU 2 via individual signal lines L1, L2, L3, L4, L5, L6, L7, and L8 for each of the injectors 101, 102, 103, 104, 105, 106, 107, and 108. Yes. The EDU 3 is connected (bus connected) to the engine ECU 2 via the communication line LC.

  And engine ECU2 produces | generates the signal of 1 pulse as injection request | requirement TQ for every injection of each of injectors 101-108, and outputs the produced | generated pulse signal to EDU3 via signal line L1-L8. That is, the engine ECU 2 starts outputting the injection request TQ corresponding to the cylinder when the timing for opening the injector of a certain cylinder is reached, and ends the output of the injection request TQ when a predetermined injection time has elapsed. The EDU 3 supplies a drive current to the injector of the cylinder corresponding to the injection request TQ while the injection request TQ is output from the engine ECU 2.

  Further, the engine ECU 2 transmits setting data for setting the injection characteristics and the like of fuel injection to the EDU 3 via the communication line LC for each of the first system and the second system. The engine ECU 2 is configured to be able to transmit setting data of a maximum of 10 blocks (in this embodiment, one block corresponds to, for example, 1-byte data) to the EDU 3 in one communication.

The setting data is classified into two types: variable data that may change for each communication and fixed data that does not change for each communication.
The variable data of the present embodiment is a current setting value that sets the magnitude of the drive current. Examples of the current setting value include a peak current value and a hold current value. The peak current value is the maximum value of the peak current that is the drive current that flows when the injector is shifted from the closed state to the open state. The hold current value is a value of a hold current that is a drive current that is supplied to hold the injector in the valve open state.

Further, as the fixed data of the present embodiment, for example, information indicating a ratio between the frequency of the internal clock of the engine ECU 2 and the frequency of the internal clock of the EDU 3 can be cited.
In this embodiment, among the 10 blocks of setting data, 3 blocks are allocated for variable data and 7 blocks are allocated for fixed data. Specifically, blocks B0, B1, B2, B3, B4, B5, B6, B7, B8, and B9 are provided for setting data communication. Blocks B0, B1, and B2 are allocated for variable data, and blocks B3, B4, B5, B6, B7, B8, and B9 are allocated for fixed data.

  When the EDU 3 receives the setting data from the engine ECU 2, the EDU 3 drives the injector so as to obtain an injection characteristic based on the received setting data, or changes the setting conditions of the EDU 3 based on the received setting data.

  Further, the engine ECU 2 measures an injection interval in the same system for each of the first system and the second system. That is, the engine ECU 2 for the first system is between the cylinder # 1 and the cylinder # 7, between the cylinder # 7 and the cylinder # 4, between the cylinder # 4 and the cylinder # 6, and between the cylinder # 6 and the cylinder #. The interval between injections with 1 is measured. In addition, the engine ECU 2 includes, for the second system, between cylinder # 2 and cylinder # 3, between cylinder # 3 and cylinder # 5, between cylinder # 5 and cylinder # 8, and between cylinder # 8 and cylinder # 8. The interval between injections between 2 is measured.

  For example, as shown in FIG. 2, in the first system, when the injector 101 of the cylinder # 1 performs fuel injection six times and then the injector 107 of the cylinder # 7 performs fuel injection five times, the engine ECU 2 The time interval from time t2 when the injector 101 ends the sixth injection to time t3 when the injector 107 starts the first injection is measured as an inter-injection interval Ti.

  Specifically, the number of fuel injections (six times in FIG. 2) to be performed on the cylinder # 1 is set before the injector 101 starts the first injection (see the required number of injections at time t1). .

Further, every time the injector 101 starts injection, the injection number counter provided in the microcomputer 10 is incremented (refer to the injection number counter at times t1 to t2).
When the value of the injection number counter matches the required number of injections, the value of the free-run counter that is counted up by the internal clock of the microcomputer 10 is acquired as the injection end time (see the injection end time at time t2) and the injection The number counter is reset (see the injection number counter at time t2).

  After that, when the injector 107 starts the first injection, the value of the free-run counter is acquired as the injection start time (see the injection start time at time t3), and the acquired injection end time and injection start time are The difference is calculated, and this difference is acquired as the interval between injections Ti (refer to the interval between injections at time t3).

  Thereafter, the communication status (described later) is determined using the injection interval Ti (see the communication status at time t4). Based on the determined communication status, the engine ECU 2 determines a transmission method of setting data (described later), selects a block to be transmitted from all 10 blocks of setting data (described later), and selects the selected block. To EDU3.

  The engine ECU 2 includes a communication command C0 for transmitting the block B0 to the EDU 3. When the engine ECU 2 selects the block B0 as the block to be transmitted, the engine ECU 2 transmits the block B0 to the EDU 3 by executing the communication command C0.

  Similarly, the engine ECU 2 transmits communication commands C1, C2, C3, C4, C5, C6, C7, C8, C9 for transmitting the blocks B1, B2, B3, B4, B5, B6, B7, B8, B9 to the EDU3. It has.

The engine ECU 2 arranges communication commands C0, C1, C2, C3, C4, C5, C6, C7, C8, and C9 in a ring buffer structure (see FIG. 4).
In the fuel injection control system 1 configured as described above, the microcomputer 10 of the engine ECU 2 executes a communication status determination process.

This communication status determination process is a process repeatedly executed during the operation of the microcomputer 10.
When this communication status determination process is executed, the microcomputer 10 first measures an injection interval Ti using the above-described method in S10 as shown in FIG. Then, in S20, it is determined whether or not the injection interval Ti is longer than the total block communication time Ta. The all block communication time Ta is a fixed value set in advance as a time required for the engine ECU 2 to transmit the setting data of all 10 blocks to the EDU 3 in one communication.

  Here, when the injection interval Ti is longer than the all-block communication time Ta (S20: YES), the communication status indicating the transmission method when the engine ECU 2 transmits the setting data to the EDU 3 is set to “3” in S30. And the communication status determination process is temporarily terminated.

  On the other hand, when the injection interval Ti is equal to or shorter than the all-block communication time Ta (S20: NO), the one-block communication time Tb is calculated in S40. The one-block communication time Tb is a time required for the engine ECU 2 to transmit one block of setting data to the EDU 3, and is calculated by dividing the total block communication time Ta by the total number of blocks (10 in this embodiment). The

Further, in S50, the number of communicable blocks Nc is calculated. The communicable block number Nc is calculated by dividing the injection interval Ti by one block communication time Tb.
Thereafter, in S60, it is determined whether or not there is a difference between the value of the variable data at the previous communication and the value of the variable data at the current communication.

  If there is a difference in the value of the variable data (S60: YES), it is determined in S70 whether or not the communicable block number Nc is equal to or greater than the variable data block number (3 in the present embodiment). . The number of variable data blocks is the number of blocks allocated for variable data among all 10 blocks that can be transmitted in one communication.

  If the communicable block number Nc is equal to or greater than the variable data block number (S70: YES), the communication status is set to “2” in S80, and the communication status determination process is temporarily terminated.

  On the other hand, when the communicable block number Nc is less than the variable data block number (S70: NO), the communication status is set to “0” in S90, and the communication status determination process is temporarily ended.

  If there is no difference in the value of the variable data at S60 (S60: NO), it is determined at S100 whether the number of communicable blocks Nc is less than one. Here, when the number of communicable blocks Nc is less than 1 (S100: YES), the communication status is set to “0” in S90, and the communication status determination process is once ended.

On the other hand, when the number Nc of communicable blocks is 1 or more (S100: NO), the communication status is set to “1” in S110, and the communication status determination process is temporarily ended.
Next, for each of the communication statuses “0”, “1”, “2”, “3”, the transmission method of the setting data and the block to be transmitted from the setting data of all 10 blocks (hereinafter referred to as a transmission block) The selection criteria when selecting) will be described.

  First, when the communication status is “3”, all the blocks B0 to B9 are selected as transmission blocks. As shown in FIG. 4, when the communication status is “3”, the communication commands C0, C1, C2, C3, C4, C5, C6, C7, C8, and C9 are arranged in one ring buffer structure. Yes. All blocks B0 to B9 are transmitted by selecting all communication commands C0 to C9. In FIG. 4, a communication command hatched with diagonal lines indicates that it is selected for transmitting the corresponding block.

  Therefore, when the communication status is “3”, when communication is started, the communication command C0 is first executed, and then the communication commands C1, C2, C3, C4, C5, C6, C7, C8, C9. Are executed sequentially (see arrow AL1). Then, when the transmission of block B9 ends, the communication ends.

  Since the communication commands C0 to C9 are arranged in one ring buffer structure, the communication command C0 is executed next to the communication command C9. That is, in the next communication, the communication command C0 is first executed.

  Next, when the communication status is “2”, the blocks B0, B1, and B2 allocated for variable data are selected as transmission blocks, and the blocks B3 to B9 allocated for fixed data are selected. Among them, (Nc-3) pieces are selected as transmission blocks. When the communication status is “2”, the communication commands C0, C1, C2 are arranged in one ring buffer structure, and the communication commands C3, C4, C5, C6, C7, C8, C9 are arranged in one ring buffer. Arranged in structure.

  Therefore, when the communication status is “2”, when communication is started, the communication command C0 is first executed, and then the communication commands C1 and C2 are sequentially executed (see arrow AL2). When transmission of block B2 ends, (Nc-3) communication commands are executed in the order of communication commands C3, C4, C5, C6, C7, C8, and C9 (see arrow AL3). For example, when the communication command C5 is executed last in the previous communication and Nc = 5, the communication commands C6 and C7 are sequentially executed in the current communication (see FIG. 4). Then, when the transmission of block B7 ends, the communication ends.

  Since the communication commands C0 to C2 are arranged in one ring buffer structure, the communication command C0 is executed next to the communication command C2. That is, in the next communication, the communication command C0 is first executed. Further, since the communication commands C3 to C9 are arranged in one ring buffer structure, the communication command C3 is executed next to the communication command C9.

  Next, when the communication status is “1”, first, data change of the blocks B0, B1, and B2 allocated for variable data is prohibited. That is, in S60, even if there is a difference between the value of the variable data at the previous communication and the value of the variable data at the current communication (S60: YES), the blocks B0, B1, B2 The value of is not changed.

  Then, Nc communication commands are executed in the order of communication commands C0, C1, C2, C3, C4, C5, C6, C7, C8, and C9 (see arrow AL4). For example, when the communication command C1 is executed last in the previous communication and Nc = 5, the communication commands C2, C3, C4, C5, and C6 are sequentially executed in the current communication (see FIG. 4). ). Then, when the transmission of block B6 ends, the communication ends.

Since the communication commands C0 to C9 are arranged in one ring buffer structure, the communication command C0 is executed next to the communication command C9.
Next, when the communication status is “0”, first, data change of the blocks B0, B1, and B2 allocated for variable data is prohibited. All blocks B0 to B9 are not selected as transmission blocks. That is, transmission of all the blocks B0 to B9 is prohibited.

  The fuel injection control system 1 configured as described above is provided in each of the plurality of cylinders # 1, # 2, # 3, # 4, # 5, # 6, # 7, and # 8 of the engine 100 to the cylinders. For each of the injectors 101, 102, 103, 104, 105, 106, 107, 108 for injecting fuel, an injection request TQ indicating the fuel injection start timing and injection time is output, and the injection characteristics of the injectors 101-108 are changed. An engine ECU 2 that controls the injectors 101 to 108 by transmitting variable data for setting, and an EDU 3 that drives the injectors 101 to 108 in accordance with the injection request TQ and variable data acquired from the engine ECU 2 are provided.

  In the fuel injection control system 1 configured as described above, the EDU 3 acquires the injection request TQ from the engine ECU 2, so that the EDU 3 starts the start timing and the injection according to the injection request TQ for each of the plurality of cylinders # 1 to # 8. The injectors 101 to 108 are driven with time, and variable data is acquired from the engine ECU 2 to drive the injectors 101 to 108 with injection characteristics according to the variable data.

  In the engine ECU 2, for the first system, between cylinder # 1 and cylinder # 7, between cylinder # 7 and cylinder # 4, between cylinder # 4 and cylinder # 6, and between cylinder # 6 and cylinder # 6. 1 between the cylinder # 2 and the cylinder # 3, between the cylinder # 3 and the cylinder # 5, and between the cylinder # 5 and the cylinder # 8. And an injection interval Ti between the cylinder # 8 and the cylinder # 2. If the time required for transmitting the variable data to the EDU 3 is longer than the injection interval Ti (S70: NO), the transmission of the variable data is prohibited (S90).

  As a result, the injectors 101, 102, 103, 104, 105, 106, 107, and 108 corresponding to the cylinders # 1, # 2, # 3, # 4, # 5, # 6, # 7, and # 8 are transferred to the cylinder # 1. , # 2, # 3, # 4, # 5, # 6, # 7, and # 8, the variable data transmission is started after the fuel injection to the cylinders # 7, # 3, # 5, respectively. Injectors 107, 103, 105, 106, 108, 101, 104, 102 corresponding to # 6, # 8, # 1, # 4, and # 2 are cylinders # 7, # 3, # 5, # 6, # 8, If it is predicted that the transmission of the variable data will be completed during the fuel injection to # 1, # 4, and # 2, the transmission of the variable data is not performed.

  For this reason, transmission of variable data is completed during the fuel injection to the cylinders # 1 to # 8, and the injection characteristics change during the fuel injection to the cylinders # 1 to # 8. The occurrence of the situation can be suppressed.

  Further, the engine ECU 2 is configured to be able to transmit fixed data to the EDU 3, and determines whether or not the contents of the variable data are different between the previous transmission of the variable data and the transmission of the current variable data. If the contents of the data are different (S60: YES) and the time required to transmit the variable data and the fixed data to the EDU 3 is shorter than the injection interval Ti, both the variable data and the fixed data Is permitted to be transmitted (S80).

  Thereby, transmission of variable data can be completed before the interval Ti between injections passes, and generation | occurrence | production of the situation where an injection characteristic changes in the middle of performing fuel injection can be suppressed.

  Further, when the fixed data acquired from the engine ECU 2 is stored in the EDU 3, even if data corruption occurs in the fixed data stored in the EDU 3, the EDU 3 stores the fixed data every time the fixed data is transmitted from the engine ECU 2. Thus, it can be updated (refreshed) to the correct value acquired from the engine ECU 2, and the garbled state can be prevented from continuing.

  Further, the engine ECU 2 permits transmission so that the variable data is transmitted before the fixed data (S80). Thereby, it is possible to suppress the occurrence of a situation in which transmission of variable data is not completed before the injection interval Ti elapses.

  Also, the engine ECU 2 permits transmission of fixed data for the number of blocks that can be transmitted before the interval Ti between injections among the fixed data of the blocks B3 to B9, and there is fixed data that has not been transmitted in the previous transmission. If it exists, in the current transmission, the fixed data not transmitted in the previous transmission is permitted with priority over the fixed data transmitted in the previous transmission (S80).

  As a result, the same fixed data is not continuously transmitted to the EDU 3, and when the EDU 3 stores the fixed data acquired from the engine ECU 2, a situation in which the specific fixed data is garbled continues. Can be suppressed.

  The engine ECU 2 does not differ in the contents of the variable data between the previous transmission of the variable data and the transmission of the current variable data, and is necessary for transmitting at least one of the variable data and the fixed data to the EDU 3. When the time is shorter than the interval between injections Ti (S100: NO), among the variable data of the blocks B0 to B2 and the fixed data of the blocks B3 to B9, the number of blocks that can be transmitted until the interval between injections Ti elapses The transmission of data is permitted without distinction between variable data and fixed data (S110).

  As a result, when the variable data acquired from the engine ECU 2 is stored in the EDU 3, even if a situation in which the content of the variable data does not change continues and data corruption occurs in the variable data stored in the EDU 3, the EDU 3 Each time variable data is transmitted from the ECU 2, the variable data can be updated (refreshed) to a correct value acquired from the engine ECU 2. For this reason, garbled data occurs in the variable data stored in the EDU 3, and it is possible to suppress a situation in which the injectors 101 to 108 are driven with inappropriate injection characteristics due to the garbled data.

  In addition, when there is data that has not been transmitted in the previous transmission among the variable data in the blocks B0 to B2 and the fixed data in the blocks B3 to B9, the engine ECU 2 transmits in the previous transmission in the current transmission. The data that has not been accepted is given priority over the data transmitted in the previous transmission (S110).

  As a result, the same data among the variable data of the blocks B0 to B2 and the fixed data of the blocks B3 to B9 is not continuously transmitted to the EDU 3, and when the EDU 3 stores the data acquired from the engine ECU 2, It is possible to suppress the occurrence of a situation in which the garbled state of specific data continues.

  In the embodiment described above, the engine 100 is the internal combustion engine according to the present invention, the injectors 101 to 108 are the fuel injection valves according to the present invention, the engine ECU 2 is the control device according to the present invention, the EDU 3 is the drive device according to the present invention, and the processing of S10 is the present processing. The interval measuring means in the invention, the processing in S90 is the prohibiting means in the present invention, the processing in S60 is the difference determining means in the present invention, the processing in S80 is the first transmission permitting means in the present invention, and the processing in S110 is the second transmission in the present invention. The permission means and the injection request TQ are the injection request signal in the present invention, and the variable data is the injection characteristic setting data in the present invention.

As mentioned above, although one Embodiment of this invention was described, this invention is not limited to the said embodiment, As long as it belongs to the technical scope of this invention, a various form can be taken.
For example, in the above-described embodiment, the injectors 101 to 108 for all eight cylinders are divided into two systems of four cylinders, but may be divided into three or more systems or one system.

  DESCRIPTION OF SYMBOLS 1 ... Fuel injection control system, 2 ... Engine ECU, 3 ... EDU, 100 ... Engine, 101, 102, 103, 104, 105, 106, 107, 108 ... Injector

Claims (5)

An injection request signal indicating a fuel injection start timing and an injection time is output for each of the fuel injection valves provided in each of the plurality of cylinders of the internal combustion engine to inject fuel into the cylinders, and injection of the fuel injection valves A control device for controlling the fuel injection valve by transmitting injection characteristic setting data for setting a characteristic;
A fuel injection control system comprising: a drive device that drives the fuel injection valve in accordance with the injection request signal and the injection characteristic setting data acquired from the control device;
The control device includes:
Among the plurality of cylinders, one of the cylinders is a first cylinder, one cylinder different from the first cylinder is a second cylinder, and the fuel injection valve corresponding to the first cylinder is the first cylinder. Interval measuring means for measuring an injection interval that is a period from when the fuel injection to the second cylinder starts until the fuel injection valve corresponding to the second cylinder starts fuel injection to the second cylinder;
Wherein when the setting data transmission time is the time required to transmit the injection characteristic setting data to the drive unit is longer than the ejection inter interval, e Bei and inhibiting means for inhibiting the transmission of the injection characteristic setting data ,
The controller is
The drive device is configured to be able to transmit fixed data that needs to be updated periodically to the drive device,
A difference determining means for determining whether or not the content of the injection characteristic setting data is different between the previous transmission of the injection characteristic setting data and the current transmission of the injection characteristic setting data;
The difference determination means determines that the contents of the injection characteristic setting data are different between the previous transmission and the current transmission, and transmits the injection characteristic setting data and the fixed data to the driving device. The fuel injection control system further comprising: a first transmission permission unit that permits transmission of both the injection characteristic setting data and the fixed data when a time required for the injection is shorter than the interval between injections. The first transmission permission unit includes:
The fuel injection control system according to claim 1 , wherein transmission is permitted so that the injection characteristic setting data is transmitted before the fixed data. A plurality of the fixed data are provided,
The first transmission permission unit includes:
Among the plurality of fixed data, allow transmission of the fixed data for the amount of data that can be transmitted before the interval between injections elapses,
Among the plurality of fixed data, those not transmitted in the previous transmission of the fixed data are set as untransmitted fixed data, and those transmitted in the previous transmission of the fixed data are set as transmitted fixed data. If the data exists in the transmission of this the fixed data, according to claim 1 or claim and permits the transmission of the untransmitted fixed data in preference to the transmission of the transmission already fixed data 3. The fuel injection control system according to 2. The control device includes:
The difference determining means determines that the content of the injection characteristic setting data is not different between the previous transmission and the current transmission, and transmits at least one of the injection characteristic setting data and the fixed data to the driving device. When the time required to do is shorter than the interval between injections, among the injection characteristic setting data and the fixed data, transmission of data for the amount of data that can be transmitted before the interval between injections elapses, the fuel injection control system according to any one of claims 1 to 3, characterized in that it comprises a second transmission permitting means for permitting without distinguishing between the injection characteristic setting data and the fixed data. A plurality of at least one of the injection characteristic setting data and the fixed data is provided,
The second transmission permission unit includes:
Among the injection characteristic setting data and the fixed data, the data that has not been transmitted in the previous data transmission is defined as untransmitted data, and the data transmitted in the previous data transmission is defined as transmitted data. In this case, in the current data transmission, the transmission of the untransmitted data is permitted in preference to the transmission of the transmitted data. The fuel injection control system according to claim 4 .