JP2023091552A - Engine start control device - Google Patents

Abstract

To provide an engine start control device capable of inhibiting erroneous starting of an engine even when an abnormality occurs in an energization line of a starter relay.SOLUTION: An engine start control device includes: a push start switch 7 for receiving a starting operation by a driver; a starter motor 21 for starting an engine 2; a starter relay 22 for turning on or off electric power supply to the starter motor 21; a first control unit 5 that detects input of a starting operation to the push start switch 7 and when it is determined that the engine 2 can be started, energizes the upstream side of the starter relay 22 in a drive current flowing direction; and a second control unit 6 that performs a failure diagnosis on the downstream side of the starter relay 22 in the drive current flowing direction in the state where the upstream side of the starter relay 22 in the drive current flowing direction is energized, and when there is no failure, energizes the downstream side of the starter relay 22 in the drive current flowing direction.SELECTED DRAWING: Figure 1

Description

The present invention relates to an engine start control device.

Patent Document 1 discloses a technique for suppressing erroneous starting of the engine when a push-type switch system fails in a control device that starts the engine by operating a switch.

JP 2007-177657 A

However, in the method of starting the engine based on switch operation, it is necessary to energize the starter relay after the switch is operated, so it is necessary to consider an abnormality in the energization line of the starter relay.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide an engine start control device capable of suppressing erroneous starting of an engine even when an abnormality occurs in an energization line of a starter relay.

In order to solve the above-mentioned problems, the present invention provides a start switch for receiving a start operation by a driver, a starter motor for starting an engine, an ON state for supplying power to the starter motor, and a cutoff of power to the starter motor. a starter relay that is controlled to be in an OFF state; a first control unit that controls energization upstream of the starter relay in an energization line through which the drive current of the starter relay flows; and energization of the energization line downstream of the starter relay. The first control unit detects that the start operation is input to the start switch, and when it is determined that the engine can be started, the The energization line upstream of the starter relay is energized, and the second control unit performs a failure diagnosis of the energization line downstream of the starter relay in a state where the energization line upstream of the starter relay is energized. If there is no failure, the energization line downstream of the starter relay is energized to drive the starter motor.

Thus, according to the present invention, it is possible to prevent the engine from being erroneously started even when an abnormality occurs in the energization line of the starter relay.

FIG. 1 is a block diagram of an engine start control device according to one embodiment of the present invention. FIG. 2 is a flow chart showing the procedure of the engine start control process of the engine start control system according to one embodiment of the present invention.

An engine start control device according to an embodiment of the present invention includes a start switch for accepting a start operation by a driver, a starter motor for starting an engine, an ON state for supplying electric power to the starter motor, and an electric power supply for the starter motor. a starter relay controlled by a first control unit that controls energization upstream of the starter relay in the energization line through which the drive current of the starter relay flows; and energization downstream of the starter relay in the energization line and a second control unit that controls, the first control unit detects that the start operation is input to the start switch, and if it is determined that the engine can be started, the starter relay of the energized line The upstream of the energized line is energized, and the second control unit performs a failure diagnosis downstream of the starter relay of the energized line while the upstream of the starter relay of the energized line is energized, and if there is no failure, the starter relay of the energized line It is configured to energize the downstream and drive the starter motor.

Thus, the engine start control device according to the embodiment of the present invention can prevent erroneous starting of the engine even when an abnormality occurs in the energization line of the starter relay.

Hereinafter, an engine start control device according to an embodiment of the present invention will be described in detail with reference to the drawings.

In FIG. 1, a vehicle 1 equipped with an engine start control device according to an embodiment of the present invention includes an engine 2, a transmission 3, a battery 4, a first control section 5, and a second control section 6. composed of

A plurality of cylinders are formed in the engine 2 . In this embodiment, the engine 2 is constructed so that each cylinder performs a series of four strokes consisting of an intake stroke, a compression stroke, an expansion stroke and an exhaust stroke.

A starter motor 21 is connected to the engine 2 . The starter motor 21 is connected to the crankshaft of the engine 2 via gears (not shown). The starter motor 21 rotates when supplied with electric power, thereby rotating the crankshaft and giving the engine 2 a rotational force for starting.

The transmission 3 shifts the rotation input from the engine 2 at a gear ratio corresponding to one of a plurality of gear stages and outputs the rotation to the main power shaft.

A clutch (not shown) is provided between the engine 2 and the transmission 3 , and the clutch connects or disconnects power transmission between the engine 2 and the transmission 3 .

The transmission 3 is configured, for example, as an AMT (Automated Manual Transmission) in which an actuator is used to switch gears and engage and disengage a clutch.

The battery 4 is composed of, for example, a lead battery. The battery 4 supplies electric power to electric loads of the vehicle 1 such as the starter motor 21 .

A starter relay 22 is provided between the battery 4 and the starter motor 21 . The starter relay 22 takes either an ON state in which the battery 4 and the starter motor 21 are electrically connected, or an OFF state in which the battery 4 and the starter motor 21 are electrically cut off. there is

The starter relay 22 is turned on by being supplied with the drive current. A starter relay upstream relay 23 is provided on the upstream side of the energization line through which the drive current flows, in the direction in which the drive current flows. A starter relay downstream relay 24 is provided on the downstream side of the energization line through which the drive current flows, in the direction in which the drive current flows.

The starter upstream relay 23 is controlled by the first control unit 5 so as to take either an ON state in which the drive current is applied or an OFF state in which the drive current is not applied.

The starter relay downstream relay 24 is controlled by the second control unit 6 to take either an ON state in which the drive current is applied or an OFF state in which the drive current is not applied.

Since both the starter relay upstream relay 23 and the starter relay downstream relay 24 are turned on, a driving current flows and the starter relay 22 is turned on.

The first control unit 5 and the second control unit 6 each include a CPU (Central Processing Unit), a RAM (Random Access Memory), a ROM (Read Only Memory), a flash memory that stores backup data, etc. It consists of a computer unit with an input port and an output port.

The ROMs of these computer units store programs for causing the computer units to function as the first control section 5 and the second control section 6, respectively, along with various constants, various maps, and the like.

That is, these computer units respectively function as the first control unit 5 and the second control unit 6 in this embodiment by the CPU executing the programs stored in the ROM using the RAM as a work area.

The first control unit 5 and the second control unit 6 are connected to an in-vehicle LAN (Local Area Network) conforming to standards such as CAN (Controller Area Network), and can mutually transmit and receive signals such as control signals. .

A push start switch 7 as a start switch is connected to the input port of the first control unit 5 . The push-start switch 7 is, for example, a momentary push-type switch, and is a switch that receives instructions from the driver such as transition of the power supply state of the vehicle 1 and start/stop of the engine 2 .

The push start switch 7 is turned on while being pressed, and outputs an on signal to the first controller 5 . On the other hand, the push start switch 7 is turned off while not being pressed, and outputs an off signal to the first controller 5 .

The first control unit 5 controls the power supply state of the vehicle 1, starting and stopping of the engine 2, and the like based on an output signal from the push start switch 7, for example.

The second control unit 6 controls the transmission 3, for example. The second control unit 6 controls, for example, the actuator of the transmission 3 to change gears and engage and disengage the clutch.

The second control unit 6 determines whether the engine 2 can be started based on, for example, the state of the transmission 3 and the state of a brake pedal (not shown) operated by the driver.

The second control unit 6 switches the gear stage of the transmission 3 according to the operation position of a shift lever (not shown) operated by the driver.

The second control unit 6 stores gear position information, which is information on the gear stage formed by the transmission 3, selector position information, which is information on the operating position of the shift lever, and whether or not the brake pedal is depressed. Brake switch information, which is information, is input.

In this embodiment, the first control unit 5 requests the second control unit 6 to determine whether the engine 2 can be started when it detects that a start operation has been input to the push start switch 7 .

When the second control unit 6 receives a request to determine whether the engine 2 can be started from the first control unit 5, the second control unit 6 determines whether the engine 2 can be started based on starting conditions such as gear position information, selector position information, and brake switch information. judge.

The second control unit 6 determines that the starting condition is met and the engine 2 can be started, for example, when the selector position is in parking or neutral, the brake is depressed, and the shift stage is in neutral. judge.

The second control unit 6 transmits to the first control unit 5 the determination result of whether or not the engine 2 can be started.
When the startability determination result of the engine 2 received from the second control unit 6 indicates that the engine 2 can be started, the first control unit 5 turns on the starter relay upstream relay 23 .

The second control unit 6 performs failure diagnosis of the starter relay downstream relay 24 when the starter relay upstream relay 23 is turned on. As for the failure diagnosis of the starter relay downstream relay 24, for example, changes in current and voltage of the starter relay downstream relay 24 are measured to perform failure diagnosis.

If the starter relay downstream relay 24 has no failure, the second control unit 6 turns on the starter relay downstream relay 24 to drive the starter motor 21 .

Engine start control processing by the engine start control apparatus according to the present embodiment configured as described above will be described with reference to FIG. The engine start control process described below is started when the first control unit 5 and the second control unit 6 start operating, and is executed at preset time intervals.

In step S1, the first control unit 5 determines whether or not the push start switch 7 has been pressed as a starting operation.

When determining that the push start switch 7 has been pressed, the first control section 5 requests the second control section 6 to determine whether the engine 2 can be started. When the second control unit 6 receives the request for judging whether or not the engine 2 can be started from the first control unit 5, the second control unit 6 executes the process of step S2. When determining that the push start switch 7 is not pressed, the first control unit 5 terminates the engine start control process.

In step S2, the second control unit 6 determines whether or not the starting condition is satisfied.
When determining that the starting condition is satisfied, the second control unit 6 transmits to the first control unit 5 a determination result indicating that the engine 2 can be started. Upon receiving the determination result indicating that the engine 2 can be started, the first control unit 5 executes the process of step S3. When determining that the starting condition is not satisfied, the second control section 6 executes the process of step S2.

In step S3, the first control unit 5 turns on the starter relay upstream relay 23 to energize the upstream of the starter relay 22, and the second control unit 6 receives information indicating that the starter relay upstream relay 23 has been turned on. to send. Upon receiving the information indicating that the starter relay upstream relay 23 has been turned on, the second control unit 6 executes the process of step S4.

In step S<b>4 , the second control unit 6 performs failure diagnosis of the starter relay downstream relay 24 . After executing the process of step S4, the second control unit 6 executes the process of step S5.

In step S<b>5 , the second control unit 6 determines whether or not there is any failure downstream of the starter relay 22 .

When determining that there is no failure downstream of the starter relay 22, the second control unit 6 executes the process of step S6. When determining that there is a failure downstream of the starter relay 22, the second control section 6 executes the process of step S7.

In step S<b>6 , the second control unit 6 turns on the starter relay downstream relay 24 to energize the downstream side of the starter relay 22 . After executing the process of step S6, the second control unit 6 transmits information indicating the end of the process to the first control unit 5, and ends the engine start control process.

In step S7, the second control unit 6 transmits to the first control unit 5 a request to de-energize the upstream of the starter relay 22, and ends the engine start control process. Upon receiving the request to de-energize the upstream of the starter relay 22, the first control unit 5 turns off the upstream starter relay 23 to de-energize the upstream of the starter relay 22, and terminates the engine start control process.

As described above, in this embodiment, when the first control unit 5 detects that the start operation is input to the push start switch 7, the first control unit 5 requests the second control unit 6 to determine whether the engine 2 can be started. 2, the starter relay upstream relay 23 is turned on. When the starter relay upstream relay 23 is turned on, the second control unit 6 performs failure diagnosis of the starter relay downstream relay 24, and if there is no failure in the starter relay downstream relay 24, the starter relay downstream relay 24 is turned on. , drives the starter motor 21 .

As a result, when it is determined that the engine 2 can be started, the starter relay upstream relay 23 is turned on, and the upstream of the starter relay 22 is energized, so that the failure diagnosis of the starter relay downstream relay 24 is performed. It becomes possible.

Conventionally, after the starter relay downstream relay 24 is turned on, the starter relay upstream relay 23 is controlled to be turned on, so failure diagnosis of the starter relay downstream relay 24 cannot be performed. Since the failure diagnosis of the starter relay downstream relay 24 cannot be performed, the starter motor 21 is driven in conjunction with the operation of the push start switch 7 when the starter relay downstream relay 24 is grounded due to failure.

By reliably diagnosing the failure of the starter relay downstream relay 24 downstream of the starter relay 22, it is possible to prevent the starter motor 21 from being driven unintentionally by the driver.

In this embodiment, when the starter relay downstream relay 24 fails, the starter relay upstream relay 23 is turned off. If another relay system is provided for energizing or de-energizing the downstream of the starter relay 22, the downstream of the starter relay 22 may be de-energized. In this case, it is premised to provide a fail-safe circuit that de-energizes the downstream side of the starter relay 22 when the relay 24 downstream of the starter relay has a failure.

In this embodiment, an example in which the first control unit 5 and the second control unit 6 perform various determinations and calculations based on various sensor information has been described. A communicable communication unit is provided, and various determinations and calculations are performed by the external device based on the detection information of various sensors transmitted from the communication unit, and the determination results and calculation results are received by the communication unit. Various controls may be performed using the determination results and calculation results obtained.

Although embodiments of the present invention have been disclosed, it will be apparent that modifications may be made by those skilled in the art without departing from the scope of the invention. All such modifications and equivalents are intended to be included in the following claims.

1 vehicle 2 engine 3 transmission 4 battery 5 first controller 6 second controller 7 push start switch (start switch)
21 starter motor 22 starter relay 23 starter relay upstream relay 24 starter relay downstream relay

Claims (3)

a start switch for receiving a start operation by a driver;
a starter motor for starting the engine;
a starter relay controlled to be in an ON state for supplying power to the starter motor and an OFF state for cutting off power to the starter motor;
a first control unit that controls energization upstream of the starter relay in the energization line through which the drive current of the starter relay flows;
a second control unit that controls energization of the energization line downstream of the starter relay,
The first control unit detects that the start operation is input to the start switch, and when it is determined that the engine can be started, energizes the energization line upstream of the starter relay, The second control unit performs a failure diagnosis downstream of the starter relay in the energized line in a state where the upstream of the starter relay in the energized line is energized, and if there is no failure, the starter in the energized line An engine start control device that energizes downstream of the relay to drive the starter motor. The first control unit controls the power supply state of the vehicle,
The engine start control device according to claim 1, wherein the second control section controls a transmission. 3. The engine start control system according to claim 2, wherein said transmission is an AMT.

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