阅读说明：本技术 内燃机控制装置 (Control device for internal combustion engine ) 是由 饭塚智 向原修 槻尾浩一 梅木孝宪 于 2019-02-14 设计创作，主要内容包括：本发明提供一种能够可靠地诊断燃料喷射切断功能是否在正常起作用、进而在燃料喷射切断功能在正常起作用的情况下许可内燃机的起动的内燃机控制装置。为此,在内燃机起动前向燃料喷射阀驱动电路(111)发送燃料喷射阀(109)的驱动禁止信号(Scut)并向燃料喷射阀驱动电路(11)发送燃料喷射阀(109)的诊断用驱动信号(Tdig),若在该情况下检测到燃料喷射阀(109)中流通了基于诊断用驱动信号(Tdig)的诊断用监视电流(Idig),则禁止内燃机的起动。通过向燃料喷射阀驱动电路(111)发送燃料喷射阀(109)的诊断用驱动信号(Tdig)并监视基于诊断用驱动信号(Tdig)的流至燃料喷射阀(109)的诊断用监视电流(Idig)的有无,能够可靠地诊断燃料喷射切断功能是否在正常起作用。(The invention provides an internal combustion engine control device capable of reliably diagnosing whether a fuel injection cut-off function is functioning normally or not and permitting the start of an internal combustion engine when the fuel injection cut-off function is functioning normally. Before the engine is started, a drive prohibition signal (Scut) for the fuel injection valve (109) is sent to the fuel injection valve drive circuit (111) and a diagnostic drive signal (Tdig) for the fuel injection valve (109) is sent to the fuel injection valve drive circuit (11), and if it is detected that a diagnostic monitor current (Idig) based on the diagnostic drive signal (Tdig) flows through the fuel injection valve (109), the engine is prohibited from being started. Whether the fuel injection shutoff function is functioning normally can be reliably diagnosed by sending a diagnostic drive signal (Tdig) for the fuel injection valve (109) to the fuel injection valve drive circuit (111) and monitoring the presence or absence of a diagnostic monitor current (Idig) flowing to the fuel injection valve (109) based on the diagnostic drive signal (Tdig).)

1. An internal combustion engine control device including a fuel injection valve drive circuit for supplying a drive current to a fuel injection valve and controlling an internal combustion engine,

the internal combustion engine control device is provided with a control unit that transmits a drive prohibition signal for the fuel injection valve to the fuel injection valve drive circuit and transmits a drive signal for the fuel injection valve to the fuel injection valve drive circuit before the internal combustion engine is started, and prohibits the internal combustion engine from being started when it is detected that a drive current based on the drive signal flows through the fuel injection valve.

2. The internal combustion engine control apparatus according to claim 1,

the current value of the drive current supplied from the fuel injection valve drive circuit to the fuel injection valve in accordance with the drive signal is set to a value at which the fuel injection valve cannot be opened.

3. The internal combustion engine control apparatus according to claim 2,

the control unit sends a drive prohibition release signal of the fuel injection valve to the fuel injection valve drive circuit after sending the drive prohibition signal,

and transmitting the drive signal of the fuel injection valve to the fuel injection valve drive circuit, in which case the current value of the drive current flowing to the fuel injection valve is set to a magnitude at which the fuel injection valve cannot be opened.

4. The internal combustion engine control apparatus according to claim 1,

the control unit sends the drive signal set to a time shorter than an invalid injection time during which the fuel injection valve cannot be opened to the fuel injection valve drive circuit.

5. The internal combustion engine control apparatus according to claim 1,

the control unit sequentially transmits the drive signals of the plurality of fuel injection valves to the fuel injection valve drive circuit at predetermined intervals in a state where the drive prohibition signal of the fuel injection valve is transmitted to the fuel injection valve drive circuit, and prohibits starting of the internal combustion engine when it is detected that the drive current based on the drive signal flows through any one of the fuel injection valves.

6. The internal combustion engine control apparatus according to claim 1,

the control portion detects the drive current based on the drive signal with a current detection portion that detects a current flowing to an exciting coil of the fuel injection valve.

7. The control device of the internal combustion engine according to claim 3,

the control portion sends the drive prohibition signal to the fuel injection valve drive circuit before the internal combustion engine is started, and then sends the drive prohibition release signal to the fuel injection valve drive circuit.

8. The control device of the internal combustion engine according to claim 3,

the power supply of the fuel injection valve may be switched to either one of a battery power supply and a high-voltage power supply obtained by boosting the voltage of the battery power supply by the fuel injection valve driving circuit,

the control portion sends the drive prohibition release signal of the fuel injection valve to the fuel injection valve drive circuit and sends the drive signal of the fuel injection valve to the fuel injection valve drive circuit before the internal combustion engine is started, and in this case, the drive current flowing from the fuel injection valve drive circuit to the fuel injection valve is supplied from the battery power supply without via the high-voltage power supply.

9. An internal combustion engine control device including a fuel injection valve drive circuit that drives a fuel injection valve, and controlling an internal combustion engine, the internal combustion engine control device being characterized in that,

the control unit is provided with the following functions:

transmitting a drive signal of the fuel injection valve to the fuel injection valve drive circuit in a state where the fuel injection valve drive circuit has been set to a fuel injection shutoff setting state before the internal combustion engine is started;

detecting whether or not a drive current based on the drive signal flows through the fuel injection valve by an operation of the fuel injection valve drive circuit; and

and prohibiting the start of the internal combustion engine when the flow of the drive current based on the drive signal is detected in the fuel injection cut setting state.

10. The internal combustion engine control apparatus according to claim 9,

the control unit has the following functions:

releasing the fuel injection cut setting state and shifting to a fuel injection cut release state if it is detected that the driving current based on the driving signal is not flowing in the fuel injection cut setting state;

transmitting the drive signal to the fuel injection valve drive circuit in the fuel injection cut release state and detecting whether the drive current based on the drive signal flows through the fuel injection valve; and

when it is detected that the drive current based on the drive signal flows through 1 of the fuel injection valves in the fuel injection shutoff cancelled state, the start of the internal combustion engine is permitted.

11. The internal combustion engine control apparatus according to claim 9,

the control unit has the following functions:

releasing the fuel injection cut setting state to set the state as a fuel injection cut release state if it is detected that the driving current based on the driving signal is not supplied in the fuel injection cut setting state;

transmitting the drive signal to the fuel injection valve drive circuit in the fuel injection cut release state and detecting whether the drive current based on the drive signal flows through the fuel injection valve;

permitting the internal combustion engine to start if it is detected that the drive current based on the drive signal flows through 1 of the fuel injection valves in the fuel injection shutoff cancellation state; and

if it is detected that the drive current based on the drive signal is not flowing through all the fuel injection valves in the fuel injection cut release state, the start of the internal combustion engine is prohibited.

12. An internal combustion engine control device including a fuel injection valve drive circuit that drives a fuel injection valve, and controlling an internal combustion engine, the internal combustion engine control device being characterized in that,

the control unit is provided with the following functions:

transmitting a drive signal of the fuel injection valve to the fuel injection valve drive circuit in a state in which the fuel injection valve drive circuit has been set to a fuel injection shutoff cancelled state before the internal combustion engine is started;

detecting whether or not a drive current based on the drive signal flows through the fuel injection valve by an operation of the fuel injection valve drive circuit;

setting a fuel injection shutoff setting state and transmitting the drive signal to the fuel injection valve drive circuit if it is detected that the drive current based on the drive signal flows through at least 1 of the fuel injection valves in the fuel injection shutoff cancelled state; and

and detecting whether or not the drive current based on the drive signal flows through the fuel injection valve, and prohibiting starting of the internal combustion engine when the flow of the drive current based on the drive signal is detected in the fuel injection cutoff setting state.

13. The internal combustion engine control device according to any one of claims 10 to 12,

the control unit sends the drive signal set to a time shorter than an invalid injection time during which the fuel injection valve cannot be opened to the fuel injection valve drive circuit.

14. The internal combustion engine control device according to any one of claims 10 to 12,

the control unit transmits the drive signal set to a time shorter than an invalid injection time during which the fuel injection valve cannot be opened to the fuel injection valve drive circuit in the fuel injection cut setting state and the fuel injection cut release state.

15. The control apparatus of the internal combustion engine according to claim 14,

the control unit sets an interval period for each of the consecutive drive signals so that the drive signal of another fuel injection valve is present between at least the consecutive drive signals applied to 1 fuel injection valve.

Technical Field

The present invention relates to an internal combustion engine control device that controls a fuel injection valve that supplies fuel to a combustion chamber of an internal combustion engine, and more particularly to an internal combustion engine control device that has a function of checking normality of a fuel injection shutoff function.

Background

In an internal combustion engine control device, when abnormality or failure of a mechanical part or a control part that affects engine torque is detected, a driver is notified of the abnormality of the internal combustion engine and a fail-safe function such as a fuel injection cut-off function, an ignition control cut-off function, a throttle fixed opening setting function, or the like is executed. However, if the fail-safe function is not operated, there is a possibility that the internal combustion engine enters a state in which the fail-safe function is required without confirming whether the fail-safe function is operated normally, and the fail-safe function is not operated, thereby causing a state in which an abnormal engine torque is generated. Therefore, it is necessary to confirm whether the fail-safe function is functioning normally.

For example, japanese patent laid-open No. 2009-: in order to confirm whether or not the fuel injection cut-off function is functioning normally at the time of fail-safe, a diagnosis period for diagnosing the fuel injection cut-off function during a period in which the operation of the internal combustion engine is stopped is set, a fuel injection cut-off signal is output to the fuel injection valve drive circuit during the diagnosis period of the fuel injection cut-off function, and the signal state of an operation state monitoring port (Disable port) of the fuel injection valve drive circuit at that time is monitored, whereby abnormality diagnosis of the fuel injection cut-off function is executed.

Disclosure of Invention

Problems to be solved by the invention

However, in patent document 1, since the signal state of the operation state monitoring port of the fuel injection valve drive circuit is monitored, it is not possible to distinguish whether the driving of the fuel injection valve is stopped due to a normal fuel injection shutoff function or the fuel injection valve is stopped due to an abnormality of the fuel injection valve drive circuit and the fuel injection control device controlling the same. Therefore, there are the following problems: the fuel injection control device assumes that the fuel injection cut-off function is not functioning normally and prohibits the start itself of the internal combustion engine, although the fuel injection cut-off function would function normally in practice. When the fuel injection valve is stopped due to an abnormality other than the abnormality of the fuel injection shutoff function, the fuel injection valve is diagnosed by another diagnostic function.

An object of the present invention is to provide an internal combustion engine control device capable of reliably diagnosing whether a fuel injection cut-off function is functioning normally, and further prohibiting the start of an internal combustion engine when it is determined that the fuel injection cut-off function is not functioning normally.

Means for solving the problems

The present invention is characterized in that a drive prohibition signal for the fuel injection valve is sent to the fuel injection valve drive circuit before the internal combustion engine is started, and the drive signal for the fuel injection valve is sent to the fuel injection valve drive circuit.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the present invention, it is possible to reliably diagnose whether the fuel injection cut-off function is functioning normally by transmitting the drive signal of the fuel injection valve to the fuel injection valve drive circuit and monitoring the presence or absence of the current flowing to the fuel injection valve based on the drive signal in a state where the fuel injection cut-off function has been activated by transmitting the drive prohibition signal of the fuel injection valve to the fuel injection valve drive circuit.

Drawings

Fig. 1 is a configuration diagram showing an overall configuration of a fuel injection system of an internal combustion engine to which the present invention is applied.

Fig. 2 is a circuit diagram showing a configuration of the fuel injection valve driving unit shown in fig. 1.

Fig. 3 is a control flowchart for determining normality of the fuel injection cut function according to embodiment 1 of the present invention.

Fig. 4 is an explanatory diagram for explaining a diagnostic drive signal applied to the fuel injection valve at the time of diagnosis.

Fig. 5 is a timing chart in the case where the fuel injection cut function does not normally function in embodiment 1.

Fig. 6 is a timing chart in the case where the fuel injection shutoff function is normally operated and abnormality occurs in 1 of the fuel injection valves.

Fig. 7 is a timing chart in a case where it is unclear whether the fuel injection cut function is functioning normally.

Fig. 8 is a timing chart in the case where the fuel injection cut function is normally operated in embodiment 1.

Fig. 9 is a control timing chart for determining normality of the fuel injection cut function in the modification of embodiment 1.

Fig. 10 is an explanatory diagram for explaining the interval period of a plurality of diagnostic drive signals applied to the same fuel injection valve at the time of diagnosis.

Fig. 11 is a control flowchart for determining normality of the fuel injection cut function according to embodiment 2 of the present invention.

Fig. 12 is a timing chart in the case where the fuel injection cut function is normally operated in embodiment 2.

Fig. 13 is a control flowchart for determining normality of the fuel injection cut function according to embodiment 3 of the present invention.

Detailed Description

Next, embodiments of the present invention will be described in detail with reference to the drawings, but the present invention is not limited to the following embodiments, and various modifications and application examples are included in the technical concept of the present invention.