JP2018071450A - Control device for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a control device for a vehicle which can turn on a power supply relay of an electric oil pump at proper timing.SOLUTION: An EOP power supply relay is arranged on a power supply line which is connected to a battery and a pump drive circuit mounted to a vehicle. When an IDS start condition is established, and a stop command (IDS command) of an engine is outputted from an IDSECU (time T1), the EOP power supply relay is turned on. After that, both an engine rotation number and a vehicle speed are lowered to zero, the electric oil pump is driven (time T3). When an output of the IDS command from the IDSECU is stopped (time T4), and a constant delay time elapses after a stop of the drive of the electric oil pump, the EOP power supply relay is turned off (time T5).SELECTED DRAWING: Figure 2

Description

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

  In recent years, IDS control has been adopted for vehicles using an engine as a drive source. IDS control is a technique for stopping unnecessary idling rotation of the engine and improving fuel consumption.

  Some vehicles adopting IDS control are equipped with an automatic transmission such as a continuously variable transmission (CVT) as a transmission for shifting power transmitted from an engine to driving wheels. A vehicle equipped with an automatic transmission requires an oil pump for generating hydraulic pressure used in the automatic transmission. If only the mechanical oil pump driven by the engine power is installed as the oil pump, the mechanical oil pump stops driving while the engine is stopped by IDS control. It cannot be secured. For this reason, some vehicles are equipped with an electric oil pump driven by the power of an electric motor in addition to a mechanical oil pump.

  FIG. 3 is a diagram showing an example of time changes 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. It is.

  When the braking force by the brake operation acts on the vehicle, the vehicle speed decreases, and when the vehicle speed of 0 km / h is detected by an IDSECU (Electronic Control Unit) for IDS control, an IDS instruction is output from the IDSECU. (Time T11). In response to the output of the IDS instruction, the engine is stopped (idling stop), and the electric oil pump is driven (ON). Since the electric oil pump generates hydraulic pressure by driving the electric oil pump, the hydraulic pressure can be supplied to a clutch or the like that is engaged / released to transmit / cut off the power between the engine and the drive wheels.

  Thereafter, when the brake operation by the driver is released and the IDS ECU 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 stop of the output of the IDS instruction. Since the clutch is engaged with the supply of hydraulic pressure before the engine is restarted, the vehicle can be started quickly as 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) in response to the stop of the output of the IDS instruction.

JP 2013-181408 A

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

  For example, the following two methods are conceivable as a method for on / off control of the EOP power relay

(1) Method 1: interlocked with 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 Relay is turned off

(2) Method 2: Linked to vehicle speed When the vehicle speed drops to 0 km / h or near 0 km / h (time T31), the EOP power relay is turned on, and the vehicle speed reaches a predetermined value while the EOP power relay is on. When it rises (time T32), the EOP power relay is turned off.

  However, in Method 1, even when the electric oil pump is not driven, the EOP power supply relay is kept on, and the amount of power consumed by turning on the EOP power supply relay is large, which is more disadvantageous than Method 2 in terms of power consumption. On the other hand, in Method 2, when the brake operation by the driver is released before the IDS instruction is output after the EOP power relay is turned on, the IDS instruction is not output, and therefore it is useless to turn on the EOP power relay. Finally, power is wasted.

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

  In order to achieve the above object, a vehicle control apparatus according to the present invention includes an engine, an automatic transmission that shifts power transmitted from the engine to wheels, an electric oil pump that generates hydraulic pressure supplied to the automatic transmission, A control device for use in a vehicle equipped with a pump drive circuit for driving an electric oil pump and a power supply relay provided on a power supply path to the pump drive circuit, the engine stop instruction according to the establishment of an IDS start condition And an IDS instruction output means for outputting a power supply relay and a relay control means for turning off the power supply relay in response to a stop instruction output by the IDS instruction output means at least in a state where the vehicle speed is equal to or higher than a predetermined value. Including.

  According to this configuration, the 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 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 equal to or higher than a predetermined value. When the IDS start condition is satisfied and an engine stop instruction (IDS instruction) is output from the IDS instruction output means, the stop instruction is received and the power supply relay is turned on.

  Since the power relay is turned off at least when the vehicle speed is equal to or higher than a predetermined value, the power relay is compared with the configuration in which the power relay is turned on / off in conjunction with turning on / off the vehicle ignition switch (method 1). When the power is on and the electric oil pump is not driven, the standby time can be reduced, and power saving can be achieved.

  Since the power relay is turned on in response to the output of the engine stop instruction, the power relay can be prevented from being turned on unnecessarily without the engine stop instruction being output after the power relay is turned on. Even when compared with a configuration in which the power relay is turned on / off in conjunction with (Method 2), power saving can be achieved. In addition, since the number of times the power relay is turned on unnecessarily is reduced compared to the configuration in which the power relay is turned on / off in conjunction with the vehicle speed (method 2), the power relay has low on / off durability and is inexpensive. Can be adopted. Therefore, the vehicle cost can be reduced.

  The relay control means may turn off the power relay in response to engine start.

  When the engine is started, the battery voltage (battery terminal voltage) is temporarily greatly reduced by the operation of the starter. When the power supply relay is turned off at this time, the microcomputer (microcontroller unit) provided in association with the pump drive circuit determines that the battery voltage temporarily lowered due to the starter operation is a low voltage abnormality. Can be suppressed. As a result, it is possible to suppress unnecessary execution of fail-safe processing (for example, prohibition of driving of the electric oil pump and prohibition of IDS) for the determination of the low voltage abnormality.

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

  According to the present invention, it is possible to reduce the standby time when the power supply relay is on and the electric oil pump is not driven, and to turn on the power supply relay at an appropriate timing that can prevent the power supply relay from being turned on wastefully. Can do. And a power saving can be achieved by turning on a power supply relay at an appropriate timing. In addition, the number of on / off times of the power relay can be reduced. As a result, an inexpensive relay with low on / off durability can be adopted as the power relay, so that the vehicle cost can be reduced.

It is a figure which shows the structure of the principal part of the vehicle by which the control apparatus which concerns on one Embodiment of this invention is mounted. It is a figure which shows an example of the time change of the output / stop of IDS instruction | indication, an engine speed, a vehicle speed, drive / stop of an electric oil pump, and ON / OFF of an EOP power supply relay. It is a figure which shows the prior art example of output / stop of IDS instruction | indication, vehicle speed, drive / stop of an electric oil pump, ON / OFF of an ignition switch, and ON / OFF of an EOP power supply relay.

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

<Vehicle configuration>
FIG. 1 is a diagram illustrating a configuration of a main part of a vehicle 1 on which a control device according to an embodiment of the present invention is mounted.

  The vehicle 1 is an automobile that uses the engine 2 as a drive source.

  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 an ignition plug that generates electric discharge in the combustion chamber. It has been. The engine 2 is also provided with a starter for starting the engine 2.

  The vehicle 1 is also equipped with a torque converter 3 and a belt-type continuously variable transmission (CVT) 4 for transmitting 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 to the primary shaft 12, A primary pulley 14 supported so as not to rotate relative to the shaft 12, a secondary pulley 15 supported so as not to rotate relative to the secondary shaft 13, and a belt 16 wound around the primary pulley 14 and the secondary pulley 15. Yes.

  The primary pulley 14 is disposed so as to face the fixed sheave 21 fixed to the primary shaft 12 with the belt 16 sandwiched between the fixed sheave 21 and is supported by the primary shaft 12 so as to be movable in the axial direction and not to be relatively rotatable. 22. 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. Yes.

  The secondary pulley 15 is disposed so as to face the fixed sheave 25 fixed to the secondary shaft 13 and the fixed sheave 25 with the belt 16 interposed therebetween, and is supported by the secondary shaft 13 so as to be movable in the axial direction but not relatively rotatable. A movable sheave 26 is provided. 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. Yes.

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

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

  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 along with the continuously variable transmission 4. Furthermore, a mechanical oil pump (MOP) 32 that is driven by the power of the engine 2 and an electric oil pump (EOP) 33 that is driven by the power of the electric motor are provided as sources of hydraulic pressure. The hydraulic circuit 31 is supplied with hydraulic pressure generated by the mechanical oil pump 32 and the electric oil pump 33 independently of each other.

  Along with the electric oil pump 33, a pump drive circuit 34 is provided. The pump drive circuit 34 includes a motor driver that drives the electric motor of the electric oil pump 33 and a microcomputer (microcontroller unit) that controls the motor driver. 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 line) from the battery mounted on the vehicle 1 to the pump drive circuit 34.

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

  Various sensors necessary for control are connected to the E / TECU 41 and the IDSECU 42, respectively.

<IDS control / EOP control / relay control>
FIG. 2 is a diagram showing an example of changes over time in output / stop of IDS instruction, engine speed, vehicle speed, drive / stop of the electric oil pump (EOP) 34, and ON / OFF of the EOP power relay 35.

  IDS control is a technique for improving fuel consumption by suppressing idling of the engine 2. As information necessary for the 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 traveling, the IDSECU 42 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 a predetermined idling stop execution vehicle speed (for example, 10 km / h) or less and the brake pedal is operated for a certain time or more. While the brake pedal is being operated, whether or not the IDS start condition is satisfied is determined at a constant cycle. When the IDS start condition is satisfied, an IDS instruction (IDS request) is output from the IDSECU 42 (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 / TECU 41 receives the output of the IDS instruction and turns on the EOP power supply relay 35.

  The E / TECU 41 prohibits the drive of the electric oil pump 33 in order to wait for activation of the microcomputer provided in the pump drive circuit 34 after the EOP power supply relay 35 is turned on for a certain drive prohibition time (time T1-T2). The drive prohibition time during which the drive of the electric oil pump 33 is prohibited is set to several hundred msec, for example.

  Thereafter, the E / TECU 41 instructs the microcomputer of the pump drive circuit 34 to drive the electric oil pump 33 at a predetermined timing, for example, when both the engine speed and the vehicle speed become zero. 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, whereby the forward clutch C is engaged.

  When an IDS instruction is output while the vehicle 1 is decelerating (deceleration IDS), a sufficient drive prohibition time elapses until the vehicle speed decreases 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 an 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 hydraulic pressure decreases while 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 zero, and the forward clutch C can be engaged without delay.

  After the start of idling stop, the IDSECU 42 determines whether or not a predetermined IDS return condition is satisfied at a constant cycle. 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 idling stop. When the IDS return condition is satisfied, the output of the IDS instruction from the IDSECU 42 is stopped (time T4). In response to the output stop of the IDS instruction (IDS return request), the E / TECU 41 operates the starter to restart the engine 2. The E / TECU 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).

  When a certain delay time (for example, several tens of milliseconds) elapses after the electric oil pump 33 is stopped, the E / TECU 41 turns off the EOP power supply relay 35 (time T5).

<Effect>
As described above, the EOP power relay is provided on the power supply path to the pump drive circuit 34 that drives the electric oil pump 33, that is, on the power 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 a stop instruction (IDS instruction) for the engine 2 is output from the IDSECU 42, the stop instruction is received and the EOP power relay 35 is turned on. Thereafter, when both the engine speed and the vehicle speed are reduced to 0, the electric oil pump 33 is driven.

  When the output of the IDS instruction from the IDSECU 42 is stopped and the drive of the electric oil pump 33 is stopped, the EOP power relay 35 is turned off when a certain delay time elapses. 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 EOP power relay 35 is turned on unnecessarily without outputting the IDS instruction. Even if compared with the method (method 2) in which the EOP power supply relay 35 is turned on / off in conjunction with the vehicle speed, power saving can be achieved. In addition, since the number of times the EOP power relay 35 is turned on unnecessarily is reduced as compared with the method (method 2) in which the EOP power relay 35 is turned on / off in conjunction with the vehicle speed, the EOP power relay 35 is turned on / off. It is possible to adopt an inexpensive one with low durability. Therefore, the cost of the vehicle 1 can be reduced.

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

  The drive of the EOP power relay 35 is stopped in response to the start of the engine 2. When the engine 2 is started, the battery voltage (battery terminal voltage) is temporarily greatly reduced by the operation of the starter. Since the EOP power supply relay 35 is turned off at this time, it is possible to prevent the microcomputer provided in the pump drive circuit 34 from determining that the battery voltage temporarily lowered due to the starter operation is a low voltage abnormality. . As a result, it is possible to suppress unnecessary execution of fail-safe processing (such as prohibition of driving of the electric oil pump 33 and prohibition of IDS) for the determination of the low voltage abnormality.

<Modification>
As mentioned above, although one Embodiment of this invention was described, this invention can also be implemented with another form.

  For example, in the above-described embodiment, the EOP power relay 35 is turned off when a certain delay time has elapsed after the electric oil pump 33 is stopped. However, the EOP power relay 35 is turned on after the engine 2 is restarted. It may be turned off when the vehicle speed increases to a predetermined value.

  In addition, although the configuration in which the E / TECU 41 and the IDSECU 42 are individually provided is taken up, the E / TECU 41 and the IDSECU 42 may be integrated as a single ECU.

  In the above-described embodiment, the continuously variable transmission 4 is taken up. However, the control device according to the present invention can also be used for a vehicle equipped with a stepped automatic transmission (AT). The control device according to the present invention can also be used in a vehicle equipped with a power split type continuously variable transmission. The power split type continuously variable transmission includes a belt-type continuously variable transmission mechanism that continuously changes power by changing a transmission ratio, and a constant transmission mechanism that changes power at a constant transmission ratio. Is a transmission that can be divided into two systems for transmission.

  In addition, various design changes can be made to the above-described 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)

Engine, automatic transmission for shifting power transmitted from the engine to wheels, electric oil pump for generating hydraulic pressure supplied to the automatic transmission, pump drive circuit for driving the electric oil pump, and pump drive circuit A control device used in a vehicle equipped with a power relay provided on a power supply path to
IDS instruction output means for outputting an instruction to stop the engine in response to establishment of an IDS start condition;
Relay control means for turning off the power supply relay and turning on the power supply relay in response to the stop instruction outputted by the IDS instruction output means at least when the vehicle speed is a predetermined value or more. apparatus.

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