Engine control device

Abstract

An engine control device including: a fuel pump driving portion that starts operating a fuel pump between when an operation permit switch is turned on and an operation permit command is given and when a starter switch is closed and a start command is given, and continuously operates the fuel pump after the start command is given; the first fuel injection control portion that causes an injector to perform first fuel injection at the start of an engine when both conditions are met that the start command is given and that the fuel pump is continuously operated for a set time or longer; and a rotating electric machine control portion that starts driving a rotating electric machine that operates as an engine starting motor when the first fuel injection is completed, and stops driving the rotating electric machine when the start of the engine is completed.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other objects and features of the present invention will be apparent from the detailed description of the preferred embodiments of the invention, which is described and illustrated with reference to the accompanying drawings, in which;

FIG. 1 is a block diagram showing a construction of hardware according to the first embodiment of the present invention;

FIG. 2 is a block diagram showing a construction of a control device including control means comprised of a microprocessor according to the first embodiment of the present invention;

FIG. 3 is a flowchart showing an example of an algorithm of a fuel pump driving processing executed by the microprocessor for constructing the control device in FIG. 2;

FIG. 4 is a flowchart showing an example of an algorithm of a starting control processing executed by the microprocessor for constructing the control device in FIG. 2;

FIGS. 5A to 5E are timing charts showing an exemplary operation of a fuel injection device and a starter motor at the start of an engine when the control device according to the first embodiment of the present invention is used;

FIGS. 6A to 6E are timing charts showing another exemplary operation of the fuel injection device and the starter motor at the start of the engine when the control device according to the first embodiment of the present invention is used;

FIGS. 7A to 7E are timing charts showing a further exemplary operation of the fuel injection device and the starter motor at the start of the engine when the control device according to the first embodiment of the present invention is used;

FIGS. 8A to 8E are timing charts showing an exemplary operation the fuel injection device and the starter motor at the start of the engine when a variant of a fuel pump driving portion is used in the control device according to the first embodiment of the present invention;

FIG. 9 is a block diagram showing a construction of the second embodiment of the present invention;

FIGS. 10A to 10E are timing charts showing an exemplary operation at the start of an engine when a control device according to the embodiment in FIG. 9 is used;

FIG. 11 is a block diagram showing a construction of hardware of a control device according to the third embodiment of the present invention;

FIG. 12 is a schematic circuit diagram showing an exemplary configuration of a starter generator drive circuit in FIG. 11;

FIG. 13 is a block diagram showing a construction of the control device including control means comprised of a microprocessor according to the third embodiment of the present invention;

FIG. 14 is a graph showing the relationship between an ineffective injection time and a driving voltage of an injector; and

FIG. 15 is a graph showing measurement results of the relationship between a battery voltage for driving a starter motor that starts an engine and an operating time of the starter motor, and the relationship between a rotational speed of the engine and the operating time of the starter motor.

Claims

1. An engine control device that controls a fuel injection device including an injector that injects fuel to be supplied to an engine and a fuel pump that supplies the fuel to said injector, and a rotating electric machine that operates as a motor that rotatably drives a crankshaft of said engine at the start of said engine, using a microprocessor, comprising: a fuel pump driving portion that starts operating said fuel pump between when an operation permit command to permit the operation of said engine is given and when a start command to start said engine is given, and continuously operates said fuel pump after said start command is given;first fuel injection control means for causing said injector to perform first fuel injection at the start of the engine when both conditions are met that said start command is given and that said fuel pump is continuously operated for a set time or longer, or when said start command is given within a set limited time after the continuous operation of said fuel pump for a time longer than said set time is stopped;rotating electric machine control means for controlling said rotating electric machine so as to start driving said rotating electric machine as the motor when said first fuel injection is completed, and stop driving said rotating electric machine as the motor when the start of said engine is completed; andnormal state fuel injection control means for causing said injector to perform fuel injection at a predetermined crank angle position of said engine.

2. The engine control device according to claim 1, wherein said fuel pump driving portion is comprised so as to operate said fuel pump for a certain time when the operation permit command to permit the operation of said engine is given, and continuously operate said fuel pump after the start command to start said engine is given.

3. The engine control device according to claim 1, wherein said fuel pump driving portion is comprised so as to start the continuous operation of said fuel pump when the start command to start said engine is given after the operation permit command to permit the operation of said engine is given, and said first fuel injection control means is configured to cause the injector to perform the first fuel injection at the start of the engine when said start command is given and the operating time of said fuel pump reaches the set time.

4. The engine control device according to claim 1, wherein said rotating electric machine is provided so as to operate as a motor that starts said engine at the start of said engine, and be driven by said engine after the start of said engine and operate as a battery charging generator, and said rotating electric machine control means is comprised so as to start driving said rotating electric machine as the motor when said first fuel injection is completed, stop the driving of said rotating electric machine as the motor when the start of said engine is completed, and control a generation output of said rotating electric machine that operates as the generator for maintaining a voltage across a battery within a set range after the start of said engine is confirmed.

5. The engine control device according to claim 4, wherein two microprocessors are provided, and said fuel pump driving portion, said first fuel injection control means, and said normal state fuel injection control means are comprised of one of said two microprocessors, and said rotating electric machine control means is comprised of the other of said two microprocessors.

6. The engine control device according to claim 1, wherein said rotating electric machine is provided so as to operate as a motor that starts said engine at the start of said engine, and be driven by said engine after the start of said engine and operate as a battery charging generator, said fuel pump driving portion is comprised so as to operate said fuel pump for a certain time when the operation permit command to permit the operation of said engine is given, and continuously operate said fuel pump after the start command to start said engine is given,said first fuel injection control means is comprised so as to cause said injector to perform first fuel injection at the start of the engine when both conditions are met that said start command is given and that said fuel pump is continuously operated for a set time or longer, andsaid rotating electric machine control means is comprised so as to start driving said rotating electric machine as the motor when said first fuel injection is completed, stop the driving of said rotating electric machine as the motor when the start of said engine is completed, and control a generation output of said rotating electric machine that operates as the generator for maintaining a voltage across a battery within a set range after the start of said engine is confirmed.

7. The engine control device according to claim 6, wherein two microprocessors are provided, and said fuel pump driving portion, said first fuel injection control means, and said normal state fuel injection control means are comprised of one of said two microprocessors, and said rotating electric machine control means is comprised of the other of said two microprocessors.

8. The engine control device according to claim 1, wherein said rotating electric machine is provided so as to operate as a motor that starts said engine at the start of said engine, and be driven by said engine after the start of said engine and operate as a battery charging generator, said fuel pump driving portion is comprised so as to start the continuous operation of said fuel pump when the start command to start said engine is given after the operation permit command to permit the operation of said engine is given,said first fuel injection control means is comprised so as to cause the injector to perform the first fuel injection at the start of the engine when said start command is given and the operating time of said fuel pump reaches the set time, andsaid rotating electric machine control means is comprised so as to start driving said rotating electric machine as the motor when said first fuel injection is completed, stop the driving of said rotating electric machine as the motor when the start of said engine is completed, and control a generation output of said rotating electric machine that operates as the generator for maintaining a voltage across a battery within a set range after the start of said engine is confirmed.

9. The engine control device according to claim 8, wherein two microprocessors are provided, and said fuel pump driving portion, said first fuel injection control means, and said normal state fuel injection control means are comprised of one of said two microprocessors, and said rotating electric machine control means is comprised of the other of said two microprocessors.