JP7016608B2 - Vehicle control device - Google Patents

Description

The present invention relates to a vehicle control device used for a vehicle that employs IDS (idling stop) control.

In recent years, IDS control has been adopted for vehicles whose drive source is an engine. IDS control is a technology for stopping unnecessary idling rotation of an engine and improving fuel efficiency.

Further, in a vehicle adopting IDS control, as a transmission for shifting the power transmitted from the engine to the drive wheels, there is a vehicle equipped with an automatic transmission such as a continuously variable transmission (CVT). Vehicles equipped with an automatic transmission require an oil pump to generate the hydraulic pressure used in the automatic transmission. If only a mechanical oil pump driven by the power of the engine is installed as an oil pump, the driving of the mechanical oil pump will be stopped while the engine is stopped by IDS control, so the hydraulic pressure required for the automatic transmission will be supplied. Cannot be secured. Therefore, some such vehicles are equipped with an electric oil pump driven by the power of an electric motor in addition to the mechanical oil pump.

FIG. 3 is a diagram showing an example of time change of output / stop of IDS instruction, vehicle speed, drive / stop of electric oil pump (EOP), on / off of ignition switch (IG), and on / off of EOP power relay. Is.

When the braking force due to the braking operation acts on the vehicle, the vehicle speed decreases, and the vehicle speed of 0 km / h is detected by the IDSECU (Electronic Control Unit) for IDS control, the IDSECU outputs an IDS instruction. (Time T11). The engine is stopped (idling stop) and the electric oil pump is driven (ON) according to the output of the IDS instruction. Since the electric oil pump generates hydraulic pressure by driving the electric oil pump, it is possible to supply hydraulic pressure to a clutch or the like that is engaged / disengaged in order to transmit / disconnect power between the engine and the drive wheels.

After that, when the brake operation by the driver is released and the IDSEC determines that the IDS has returned, the output of the IDS instruction from the IDSECU is stopped (time T12). The engine is restarted in response to the stoppage of the output of the IDS instruction. Since the clutch is supplied with hydraulic pressure and engaged before the engine is restarted, the vehicle can be started quickly when the engine is restarted. Further, when the engine is restarted, the mechanical oil pump is driven by the power of the engine, so that it is not necessary to generate hydraulic pressure by the electric oil pump. Therefore, the drive of the electric oil pump is stopped (OFF) according to the stop of the output of the IDS instruction.

Japanese Unexamined Patent Publication No. 2013-181408

A battery mounted on the vehicle is connected to the pump drive circuit that drives the electric oil pump via an EOP power relay. When the EOP power relay is turned on, power is supplied from the battery to the pump drive circuit, and the electric oil pump can be driven by the pump drive circuit. Turning off the EOP power relay electrically disconnects the pump drive circuit from the battery.

As the method of on / off control of the EOP power relay, for example, the following two methods can be considered.

(1) Method 1: Interlocking with the ignition switch When the ignition key switch of the vehicle is turned on (time T21), the EOP power relay is turned on, and when the ignition key switch is turned off (time T22), the EOP power supply is turned on. Relay is turned off

(2) Method 2: Linked to the vehicle speed When the vehicle speed drops to around 0 km / h or 0 km / h (time T31), the EOP power relay is turned on and the vehicle speed reaches the specified value with the EOP power relay turned on. When rising (time T32), the EOP power relay is turned off.

However, in the method 1, the EOP power relay is kept on even when the electric oil pump is not driven, and the amount of power consumed by turning on the EOP power relay is large, which is disadvantageous in terms of power consumption as compared with the method 2. On the other hand, in the method 2, if the brake operation by the driver is released after the EOP power relay is turned on and before the IDS instruction is output, the IDS instruction is not output, so that the EOP power relay is uselessly turned on. The power is wasted.

An object of the present invention is to provide a vehicle control device capable of turning on a power relay of an electric oil pump at an appropriate timing.

In order to achieve the above object, the vehicle control device according to the present invention includes an engine, an automatic relay that shifts power transmitted from the engine to wheels, and an electric oil pump that generates hydraulic pressure to be supplied to the automatic relay. It is a control device used for vehicles equipped with a pump drive circuit that drives an electric oil pump and a power relay provided on a power supply path to the pump drive circuit, and is an engine stop instruction when the IDS start condition is satisfied. The IDS instruction output means for outputting the power relay and the relay control means for turning off the power relay and turning on the power relay in response to the stop instruction output by the IDS instruction output means at least when the vehicle speed is at least a predetermined value. include.

According to this configuration, a power relay is provided on the power supply path to the pump drive circuit that drives the electric oil pump, for example, on the power supply line connected to the battery mounted on the vehicle and the pump drive circuit. ing. The power relay is turned off at least when the vehicle speed is at least a predetermined value. When the IDS start condition is satisfied and the engine stop instruction (IDS instruction) is output from the IDS instruction output means, the power relay is turned on in response to the stop instruction.

Since the power relay is turned off at least when the vehicle speed is at least a predetermined value, the power relay is turned on / off in conjunction with the on / off of the ignition switch of the vehicle (method 1). It is possible to reduce the standby time when the electric oil pump is not driven when is on, and it is possible to achieve power saving.

Since the power relay is turned on according to the output of the engine stop instruction, it is possible to prevent the power relay from being turned on unnecessarily without the engine stop instruction being output after the power relay is turned on, and the vehicle speed. Compared with the configuration (method 2) in which the power relay is turned on / off in conjunction with the above, power saving can be achieved. In addition, compared to the configuration in which the power relay is turned on / off in conjunction with the vehicle speed (method 2), the number of times the power relay is turned on unnecessarily is reduced, so the power relay is turned on / off at low cost and with low durability. It is possible to adopt something like that. Therefore, the vehicle cost can be reduced.

The relay control means may turn off the power relay as the engine starts.

When the engine is started, the battery voltage (battery terminal voltage) temporarily drops significantly due to the operation of the starter. Since the power relay is turned off at this time, the microcomputer (microcontroller unit) provided along with the pump drive circuit determines that the temporary drop in battery voltage due to the operation of the starter is a low voltage abnormality. Can be suppressed. As a result, it is possible to prevent the fail-safe process (prohibition of driving the electric oil pump, prohibition of IDS, etc.) for determining the low voltage abnormality from being unnecessarily executed.

Since the starter is started when the engine is started, the start of the engine and the start of the starter are equivalent with respect to the timing of turning off the power relay. Further, when the engine is started in response to the output stop of the IDS instruction (IDS return request), the start of the engine and the output stop of the IDS instruction are equivalent with respect to the timing of turning off the power relay.

According to the present invention, the power relay is turned on at an appropriate timing, which can reduce the standby time when the power relay is on and the electric oil pump is not driven, and can prevent the power relay from being turned on unnecessarily. Can be done. Then, power saving can be achieved by turning on the power relay at an appropriate timing. In addition, the number of times the power relay is turned on / off can be reduced. As a result, it becomes possible to adopt an inexpensive power relay having low on / off durability, so that the vehicle cost can be reduced.

It is a figure which shows the structure of the main part of the vehicle which mounted the control device which concerns on one Embodiment of this invention. It is a figure which shows an example of the time change of the output / stop of an IDS instruction, the engine speed, the vehicle speed, the drive / stop of an electric oil pump, and the on / off of an EOP power supply relay. It is a figure which shows the conventional example of the time change of the output / stop of an IDS instruction, the vehicle speed, the drive / stop of an electric oil pump, the on / off of an ignition switch, and the on / off of an EOP power relay.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

<Main part composition of the vehicle>
FIG. 1 is a diagram showing a configuration of a main part of a vehicle 1 equipped with a control device according to an embodiment of the present invention.

The vehicle 1 is an automobile whose drive source is the engine 2.

The engine 2 is provided with an electronic throttle valve for adjusting the amount of intake air into the combustion chamber of the engine 2, an injector (fuel injection device) that injects fuel into the intake air, and a spark plug that causes an electric discharge in the combustion chamber. Has been done. Further, the engine 2 is provided with a starter for starting the engine 2.

Further, the vehicle 1 is equipped with a torque converter 3 and a belt-type continuously variable transmission (CVT) 4 in order to transmit the output of the engine 2 to the drive wheels.

The continuously variable transmission 4 includes an input shaft 11 to which power from the engine 2 is input, a primary shaft 12 to which power is transmitted from the input shaft 11, a secondary shaft 13 provided in parallel with the primary shaft 12, and a primary. A primary pulley 14 supported by a shaft 12 so as to be relatively non-rotatable, a secondary pulley 15 supported by a secondary shaft 13 so as to be relatively non-rotatable, and a belt 16 wound around the primary pulley 14 and the secondary pulley 15 are provided. There is.

The primary pulley 14 is arranged so as to face the fixed sheave 21 fixed to the primary shaft 12 with the belt 16 interposed therebetween, and is supported by the primary shaft 12 so as to be movable in the axial direction and non-relatively rotatable. It has 22 and. A piston 23 fixed to the primary shaft 12 is provided on the opposite side of the movable sheave 22 from the fixed sheave 21, and a piston chamber (hydraulic chamber) 24 is formed between the movable sheave 22 and the piston 23. There is.

The secondary pulley 15 is arranged to face the fixed sheave 25 fixed to the secondary shaft 13 with the belt 16 interposed therebetween, and is supported by the secondary shaft 13 so as to be movable in the axial direction and non-relatively rotatable. It is equipped with a movable sheave 26. A piston 27 fixed to the secondary shaft 13 is provided on the opposite side of the movable sheave 26 from the fixed sheave 25, and a piston chamber (hydraulic chamber) 28 is formed between the movable sheave 26 and the piston 27. There is.

Although not shown, a bias spring for applying an initial pinching pressure (initial thrust) to the belt 16 is interposed between the movable sheave 26 and the piston 27. The elastic force of the bias spring urges the movable sheave 26 and the piston 27 in a direction in which they are separated from each other.

A hydraulic forward clutch C is interposed between the torque converter 3 and the input shaft 11. The forward clutch C is engaged / disengaged to transmit / disengage the power from the engine 2.

Further, along with the continuously variable transmission 4, a hydraulic circuit 31 for supplying hydraulic pressure to the torque converter 3, the primary pulley 14, the secondary pulley 15, the forward clutch C, and the like is provided. Further, as a source of hydraulic pressure, a mechanical oil pump (MOP) 32 driven by the power of the engine 2 and an electric oil pump (EOP) 33 driven by the power of the electric motor are provided. The hydraulic pressure circuit 31 is supplied with hydraulic pressure generated by the mechanical oil pump 32 and the electric oil pump 33 independently of each other.

A pump drive circuit 34 is provided along with the electric oil pump 33. The pump drive circuit 34 includes a motor driver that drives the electric motor of the electric oil pump 33, a microcomputer (microcontroller unit) that controls the motor driver, and the like. A battery mounted on the vehicle 1 is connected to the pump drive circuit 34 via an EOP power relay 35. In other words, the EOP power relay 35 is provided on the power supply path (power supply line) from the battery mounted on the vehicle 1 to the pump drive circuit 34.

The vehicle 1 is provided with an ECU (Electronic Control Unit) having a configuration including a microcomputer. The microcomputer has, for example, a CPU, ROM and RAM, a data flash (flash memory), and the like. In order to control each part of the vehicle 1, a plurality of ECUs are mounted on the vehicle 1, and each ECU is connected so as to be capable of bidirectional communication by a CAN (Controller Area Network) communication protocol. The plurality of ECUs include an E / T ECU 41 for controlling the engine 2, a torque converter 3 and a continuously variable transmission 4, and an IDSE ECU 42 for IDS (idling stop) control. The pump drive circuit 34 and the EOP power relay 35 are controlled by, for example, the E / T ECU 41.

Various sensors required for control are connected to the E / T ECU 41 and the IDSE U 42, respectively.

<IDS control / EOP control / relay control>
FIG. 2 is a diagram showing an example of time change of output / stop of IDS instruction, engine speed, vehicle speed, drive / stop of electric oil pump (EOP) 34, and on / off of EOP power relay 35.

IDS control is a technique for improving fuel efficiency by suppressing idling of the engine 2. As information necessary for IDS control, information such as the vehicle speed and the operation amount of the brake pedal is input to the IDSECU 42.

In the IDS control, when the brake pedal is operated (depressed) while the vehicle 1 is running, the IDSEC U42 determines whether or not a predetermined IDS start condition is satisfied. The IDS start condition includes, for example, a condition that the vehicle speed is equal to or less than a predetermined idling stop implementation vehicle speed (for example, 10 km / h), and the brake pedal is operated for a certain period of time or longer. While the brake pedal is being operated, it is determined at regular intervals whether or not the IDS start condition is satisfied. Then, when the IDS start condition is satisfied, the IDS ECU 42 outputs an IDS instruction (IDS request) (time T1).

The E / TECU 41 receives the output of the IDS instruction from the IDSECU 42 and stops the engine 2 (idling stop). Further, the E / T ECU 41 receives the output of the IDS instruction and turns on the EOP power relay 35.

During a certain drive prohibition time (time T1-T2) from turning on the EOP power relay 35, the E / T ECU 41 prohibits the drive of the electric oil pump 33 because it waits for the microcomputer provided in the pump drive circuit 34 to start. The drive prohibition time during which the drive of the electric oil pump 33 is prohibited is set to, for example, several hundred msec.

After that, at a predetermined timing, for example, when both the engine speed and the vehicle speed become 0, the E / T ECU 41 instructs the microcomputer of the pump drive circuit 34 to drive the electric oil pump 33. In response to this drive instruction, the electric oil pump 33 is driven (ON) (time T3). When the electric oil pump 33 is turned on, the electric oil pump 33 generates hydraulic pressure, and the generated hydraulic pressure is supplied to the forward clutch C to engage the forward clutch C.

When the IDS instruction is output during the deceleration running of the vehicle 1 (deceleration IDS), a sufficient drive prohibition time elapses until the vehicle speed drops to 0 km / h. Therefore, the electric oil pump 33 can be driven without delay when both the engine speed and the vehicle speed become zero. Further, even when the IDS instruction is output in response to the stop of the vehicle 1 (stopped IDS), depending on the idling speed of the engine 2, the oil pressure decreases as the engine speed decreases from the stop of the engine 2. Since the drive prohibition time elapses, the electric oil pump 33 can be driven at the timing when both the engine speed and the vehicle speed become 0, and the forward clutch C can be engaged without delay.

After the start of idling stop, the IDSECU 42 determines at a fixed cycle whether or not the predetermined IDS return condition is satisfied. The IDS return condition includes, for example, a condition that the operation of the brake pedal is released (the driver's foot is released from the brake pedal) during the idling stop. When the IDS return condition is satisfied, the output of the IDS instruction from the IDSECU 42 is stopped (time T4). Upon receiving the output stop of the IDS instruction (IDS return request), the E / T ECU 41 operates the starter to restart the engine 2. Further, the E / T ECU 41 instructs the microcomputer of the pump drive circuit 34 to stop driving the electric oil pump 33. In response to this stop instruction, the drive of the electric oil pump 33 is stopped (OFF).

Then, when a certain delay time (for example, several tens of msec) has elapsed from the drive stop of the electric oil pump 33, the E / T ECU 41 turns off the EOP power supply relay 35 (time T5).

<Action effect>
As described above, the EOP power relay is on the power supply path to the pump drive circuit 34 that drives the electric oil pump 33, that is, on the power supply line connected to the battery mounted on the vehicle 1 and the pump drive circuit 34. 35 is provided. When the IDS start condition is satisfied and the engine 2 stop instruction (IDS instruction) is output from the IDSECU 42, the EOP power relay 35 is turned on in response to the stop instruction. After that, when both the engine speed and the vehicle speed decrease to 0, the electric oil pump 33 is driven.

When a certain delay time elapses after the output of the IDS instruction from the IDSECU 42 is stopped and the driving of the electric oil pump 33 is stopped, the EOP power supply relay 35 is turned off. Therefore, compared to the method (method 1) in which the EOP power relay 35 is turned on / off in conjunction with the on / off of the ignition switch of the vehicle 1, the EOP power relay 35 is on and the electric oil pump 33 is not driven. The standby time can be reduced and power saving can be achieved.

Further, since the EOP power relay 35 is turned on in response to the output of the IDS instruction, after the EOP power relay 35 is turned on, the IDS instruction is not output and the EOP power relay 35 is turned on in vain. It can be suppressed, and power saving can be achieved even when compared with the method (method 2) of turning on / off the EOP power relay 35 in conjunction with the vehicle speed. Further, as compared with the method of turning on / off the EOP power relay 35 in conjunction with the vehicle speed (method 2), the number of times the EOP power relay 35 is unnecessarily turned on is reduced, so that the EOP power relay 35 is turned on / off. It is possible to adopt an inexpensive one with low durability. Therefore, the cost of one vehicle can be reduced.

Therefore, the EOP power relay 35 is turned on at an appropriate timing, which can reduce the standby time when the EOP power relay 35 is turned on and the electric oil pump 33 is not driven, and can prevent the EOP power relay 35 from being turned on unnecessarily. Can be. Then, by turning on the EOP power relay 35 at an appropriate timing, power saving can be achieved.

The drive of the EOP power relay 35 is stopped according to the start of the engine 2. When the engine 2 is started, the battery voltage (battery terminal voltage) temporarily drops significantly due to the operation of the starter. By turning off the EOP power relay 35 at this time, it is possible to suppress the microcomputer provided in the pump drive circuit 34 from determining the temporary drop state of the battery voltage due to the operation of the starter as a low voltage abnormality. .. As a result, it is possible to prevent the fail-safe process (prohibition of driving of the electric oil pump 33, prohibition of IDS, etc.) for determining the low voltage abnormality from being unnecessarily executed.

<Modification example>
Although one embodiment of the present invention has been described above, the present invention can also be implemented in other embodiments.

For example, in the above-described embodiment, the EOP power relay 35 is turned off when a certain delay time elapses from the drive stop of the electric oil pump 33, but the EOP power relay 35 is used after the engine 2 is restarted. It may be turned off when the vehicle speed rises to a predetermined value.

Further, although the configuration in which the E / T ECU 41 and the ID SECU 42 are individually provided is taken up, the E / T ECU 41 and the ID SE ECU 42 may be integrated as a single ECU.

In the above-described embodiment, the continuously variable transmission 4 is taken up, but the control device according to the present invention can also be used for a vehicle equipped with a stepped automatic transmission (AT: Automatic Transmission). Further, the control device according to the present invention can also be used for a vehicle equipped with a power split type continuously variable transmission. The power split type continuously variable transmission is equipped with a belt-type continuously variable transmission mechanism that shifts power steplessly by changing the gear ratio and a constant transmission mechanism that shifts power at a constant gear ratio, and power of a drive source. Is a transmission that can be transmitted by dividing it into two systems.

In addition, various design changes can be made to the above-mentioned configuration within the scope of the matters described in the claims.

1: Vehicle 2: Engine 4: Continuously variable transmission (automatic transmission)
33: Electric oil pump 34: Pump drive circuit 35: EOP power relay 41: E / TECU (control device, relay control means)
42: IDSECU (control device, IDS instruction output means)

Claims (1)

An engine, a mechanical oil pump driven by the power of the engine , an automatic transmission that shifts the power transmitted from the engine to the wheels, an electric oil pump that generates hydraulic pressure supplied to the automatic transmission, and the electric oil. A control device used in a vehicle equipped with a pump drive circuit for driving a pump and a power relay provided on a power supply path to the pump drive circuit.
An IDS instruction output means that outputs an engine stop instruction according to the satisfaction of the IDS start condition, and an IDS instruction output means.
In response to the stop instruction output by the IDS instruction output means, the power relay is turned from off to on, and then the electric oil pump of the electric oil pump until both the engine speed and the vehicle speed of the vehicle become zero . The drive is prohibited , the electric oil pump is driven at the timing when both the engine rotation speed and the vehicle speed of the vehicle become 0, and the output of the stop instruction is stopped by the IDS instruction output means. A vehicle control device including a relay control means for stopping the drive of the electric oil pump and turning off the power supply relay when a certain delay time elapses from the drive stop of the electric oil pump .

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