Hybrid vehicle control device

Abstract

To provide a control device of a hybrid vehicle that can improve operability for inhibiting an engine from automatically stopping.SOLUTION: A control device of a hybrid vehicle which, when a stepping-in amount to an accelerator pedal is below a predetermined amount or less during hybrid travel, makes an engine automatically stop and transfers the vehicle into motor travel in which the vehicle travels by power of a high-voltage motor, is provided with a contact sensor for detecting contact with a portion of the accelerator pedal and, when the contact sensor detects the contact, inhibits the engine from automatically stopping.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a control device for a hybrid vehicle. [Background technology]

[0002] Patent Document 1 discloses a technology in which when the accelerator operation amount is below a predetermined value, the vehicle enters a motor driving mode in which the vehicle runs only on the motor, and when the accelerator operation amount exceeds the predetermined value, the vehicle transitions to hybrid driving in which the engine is also used. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2011-140275 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the conventional technology proposed in Patent Document 1, when traveling on a flat road, for example, when there is an uphill road in the traveling direction and torque is required, in a situation where the driver wants to start the engine in advance, the driver must depress the accelerator pedal more than a predetermined amount in order to start the engine. Therefore, in a situation where the driver wants to start the engine in advance as described above, the driver must depress the accelerator pedal even in a situation where the accelerator pedal does not need to be depressed much, and there is a possibility that the engine will not be started as intended by the driver.

[0005] In addition, some vehicles are equipped with a switch on the instrument panel that prevents the engine from automatically stopping, but preventing the engine from automatically stopping requires operations that are separate from driving operations while driving, which poses the problem of low operability.

[0006] The present invention has been made to solve the above-mentioned problems, and aims to provide a control device for a hybrid vehicle that can improve operability for prohibiting automatic engine stop. [Means for solving the problem]

[0007] The control device for a hybrid vehicle of the present invention is equipped with an engine, an electric motor, and an accelerator pedal, and when the accelerator pedal is depressed an amount less than a predetermined amount during hybrid driving in which the vehicle runs on power output from the engine, or the engine and the electric motor, the control device automatically stops the engine and transitions to motor driving in which the vehicle runs on power from the electric motor.The accelerator pedal is provided with a sensor that detects contact with a part of the accelerator pedal, and has a control unit that prohibits the automatic stopping of the engine when the contact is detected by the sensor. Effect of the Invention

[0008] The present invention can provide a control device for a hybrid vehicle that can improve the operability of prohibiting the automatic engine stop. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a schematic diagram of a hybrid vehicle according to an embodiment of the present invention. [Diagram 2] FIG. 2 is a conceptual diagram for explaining the arrangement of a contact sensor in one embodiment of the present invention, in which (a) shows an example of a state in which the accelerator pedal is depressed in a situation in which it is not necessary to depress the accelerator pedal heavily, and (b) shows an example of a state in which the accelerator pedal is depressed in a situation in which it is necessary to depress the accelerator pedal heavily. [Diagram 3] FIG. 3 is a flowchart showing the engine automatic stop control operation of the control device for a hybrid vehicle according to one embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] A control device for a hybrid vehicle according to one embodiment of the present invention includes an engine, an electric motor, and an accelerator pedal, and when the accelerator pedal is depressed by a predetermined amount or less during hybrid driving in which the vehicle runs on power output from the engine or the engine and the electric motor, the control device automatically stops the engine and transitions to motor driving in which the vehicle runs on power from the electric motor, the control device is characterized in that the accelerator pedal is provided with a sensor that detects contact with a part of the accelerator pedal, and has a control unit that prohibits automatic stopping of the engine when contact is detected by the sensor. As a result, the control device for a hybrid vehicle according to one embodiment of the present invention can improve operability for prohibiting automatic stopping of the engine. EXAMPLES

[0011] A hybrid vehicle equipped with a control device for a hybrid vehicle according to an embodiment of the present invention will now be described with reference to the drawings.

[0012] As shown in FIG. 1, the hybrid vehicle 1 includes an engine 2, a clutch 3, a high-voltage motor 4, drive wheels 5, an inverter 6, a high-voltage battery 7, an ISG 8, a starter 9, a low-voltage battery 10, and an ECU (Electronic Control Unit) 11 as a control unit.

[0013] The engine 2 is formed with a plurality of cylinders. In this embodiment, the engine 2 is configured to perform a series of four strokes, which are an intake stroke, a compression stroke, an expansion stroke, and an exhaust stroke, for each cylinder. The engine 2 generates power by performing the series of four strokes.

[0014] The clutch 3 is, for example, a normally closed type dry clutch. The clutch 3 connects or disconnects a power transmission path between the engine 2 and the high-voltage motor 4. A transmission (not shown) is provided in the power transmission path between the clutch 3 and the high-voltage motor 4.

[0015] The transmission provided in the power transmission path between the clutch 3 and the high-voltage motor 4 may be a manual transmission such as an MT (Manual Transmission), or an automatic transmission such as a CVT (Continuously Variable Transmission), an AT (Automatic Transmission), a DCT (Dual-Clutch Transmissions), or an AGS (Auto Gear Shift).

[0016] High-voltage motor 4 is connected to drive wheels 5 so as to be able to transmit power to them. High-voltage motor 4 functions as an electric motor, and drives drive wheels 5 with power supplied from high-voltage battery 7 via inverter 6. High-voltage battery 7 is made up of a rechargeable secondary battery, and is, for example, a lithium-ion battery capable of generating an output voltage of 100V.

[0017] In addition, the high-voltage motor 4 functions as a generator, converting the power generated by the engine 2 or the driving force of the drive wheels 5 into electricity and supplying it to the high-voltage battery 7 via the inverter 6, thereby charging the high-voltage battery 7.

[0018] The ISG 8 functions as an electric motor and restarts the engine 2 from a stopped state. The ISG 8 can also assist the running of the hybrid vehicle 1. The starter 9 provides the engine 2 with a rotational force at the time of starting.

[0019] The ISG 8 and the starter 9 are driven by power supplied from a low-voltage battery 10. The low-voltage battery 10 is configured by a rechargeable secondary battery, for example, a lead battery capable of generating an output voltage of 12 V.

[0020] The ECU 11 is composed of a computer unit equipped with a CPU (Central Processing Unit), a RAM (Random Access Memory), a ROM (Read Only Memory), a flash memory for storing backup data, etc., an input port, an output port, and a communication module.

[0021] The ROM of this computer unit stores various constants, various maps, and the like, as well as a program for causing the computer unit to function as the ECU 11.

[0022] That is, the CPU executes the programs stored in the ROM using the RAM as a working area, whereby this computer unit functions as the ECU 11 in this embodiment.

[0023] An input port of the ECU 11 is connected to various sensors including an accelerator pedal position sensor 13 that detects the amount of operation of the accelerator pedal 12 (hereinafter also referred to as "accelerator position") and a contact sensor 14 that detects contact with a part of the accelerator pedal 12. An output port of the ECU 11 is connected to various control targets including the inverter 6, the ISG 8, and the starter 9.

[0024] The contact sensor 14 is, for example, composed of a piezoelectric element. The contact sensor 14 is provided in the front part of the accelerator pedal 12 because, as shown in FIG. 2(a), when the driver does not need to depress the accelerator pedal 12 deeply, the driver does not depress the accelerator pedal 12 deeply, and, as shown in FIG. 2(b), when the driver needs to depress the accelerator pedal 12 deeply, the driver tends to depress the accelerator pedal 12 deeply. The front part of the accelerator pedal 12 means the toe side of the foot of the driver who depresses the accelerator pedal 12, or the upper side in the example shown in FIG. 2. The contact sensor 14 may be provided in a position where the driver does not normally depress the accelerator pedal 12. For example, a protruding piece is provided on the left and right or on the upper side of the upper end side of the accelerator pedal 12, and the contact sensor 14 is provided on the protruding piece.

[0025] In FIG. 1, an ECU 11 controls an engine 2 and a high-voltage motor 4 by outputting control signals to various controlled objects connected to its output ports in response to detection signals input from various sensors connected to its input ports.

[0026] The ECU 11 switches the driving mode between hybrid driving, in which the vehicle runs on power output from the engine 2 or the engine 2 and the high-voltage motor 4, and motor driving, in which the vehicle runs on power output from the high-voltage motor 4.

[0027] For example, when the accelerator pedal 12 is depressed to a predetermined amount or less during hybrid driving, the ECU 11 automatically stops the engine 2 and switches the driving mode to motor driving. The predetermined amount is a suitable value determined by verification so that the required torque can be output while maintaining high fuel efficiency.

[0028] When contact is detected by the contact sensor 14 during hybrid running, the ECU 11 prohibits the automatic stop of the engine 2. That is, when the vehicle is running in hybrid running, the ECU 11 prohibits the automatic stop of the engine 2 while contact is detected by the contact sensor 14, and permits the automatic stop of the engine 2 while contact is not detected by the contact sensor 14.

[0029] Therefore, for example, in a situation where it is not desired to automatically stop the engine 2 while the hybrid vehicle 1 is traveling on a flat road, such as when the hybrid vehicle 1 is traveling in hybrid mode and it is known that torque is required due to an uphill road in the direction of travel of the hybrid vehicle 1, the driver can prohibit the automatic stopping of the engine 2 by contacting the contact sensor 14.

[0030] Furthermore, when the contact sensor 14 detects contact for a predetermined time (e.g., 3 seconds) or more during hybrid running, the ECU 11 sets the automatic stop prohibition state to prohibit automatic stopping of the engine 2 until the hybrid vehicle 1 stops, even if the contact sensor 14 no longer detects contact. As a result, even if the contact sensor 14 does not continue to detect contact, the automatic stop of the engine 2 can be prohibited for a long period of time by setting the automatic stop prohibition state.

[0031] Furthermore, in order to enable the driver to cancel the automatic stop prohibition state at his / her will, when the contact sensor 14 detects another contact during the automatic stop prohibition state, the ECU 11 cancels the automatic stop prohibition state.

[0032] The engine automatic stop control operation of the ECU 11 configured as above will be described with reference to Fig. 3. The engine automatic stop control operation described below is repeatedly executed at predetermined time intervals during hybrid driving.

[0033] 3, in S1, the ECU 11 determines whether or not contact has been detected by the contact sensor 14. If it is determined in S1 that contact has been detected by the contact sensor 14, the ECU 11 executes processing in S2. If it is determined in S1 that contact has not been detected by the contact sensor 14, the ECU 11 executes processing in S6.

[0034] In S2, if the automatic stop of the engine 2 is not prohibited, the ECU 11 prohibits the automatic stop of the engine 2. After executing the process of S2, the ECU 11 executes the process of S3.

[0035] In S3, the ECU 11 determines whether the period during which contact is detected by the contact sensor 14 is equal to or longer than a predetermined time. If it is determined in S3 that the period during which contact is detected by the contact sensor 14 is equal to or longer than the predetermined time, the ECU 11 executes processing in S4. If it is determined in S3 that the period during which contact is detected by the contact sensor 14 is not equal to or longer than the predetermined time, the ECU 11 executes processing in S5.

[0036] In S4, if the automatic stop prohibition state is not set, the ECU 11 sets the automatic stop prohibition state. When the hybrid vehicle 1 stops, the ECU 11 cancels the automatic stop prohibition state. After executing the process of S4, the ECU 11 ends the engine automatic stop control operation. In S5, if the automatic stop prohibition state is set, the ECU 11 cancels the automatic stop prohibition state. After executing the process of S5, the ECU 11 ends the engine automatic stop control operation.

[0037] In S6, the ECU 11 judges whether or not the automatic stop prohibition state is established. If it is determined in S6 that the automatic stop prohibition state is established, the ECU 11 ends the engine automatic stop control operation. As a result, the automatic stop prohibition state is maintained. If it is determined in S6 that the automatic stop prohibition state is not established, the ECU 11 executes the process of S7. In S7, the ECU 11 permits automatic stopping of the engine 2. After executing the process of S7, the ECU 11 ends the engine automatic stop control operation.

[0038] As described above, the control device for a hybrid vehicle according to this embodiment can prohibit the automatic stopping of the engine regardless of the accelerator opening when contact is detected by the contact sensor 14 provided on the accelerator pedal 12. This makes it possible to prohibit the automatic stopping of the engine 2 simply by changing the position at which the accelerator pedal 12 is depressed, thereby improving the operability for prohibiting the automatic stopping of the engine 2.

[0039] In addition, the control device for the hybrid vehicle in this embodiment can prohibit automatic stopping of the engine when contact is detected by the contact sensor 14 provided on the accelerator pedal 12, regardless of the accelerator opening degree, so that it can control the engine 2 by distinguishing between a situation where the accelerator pedal 12 is depressed and a situation where the required torque is not high, i.e., the accelerator pedal 12 is not depressed.

[0040] In addition, the control device for the hybrid vehicle according to this embodiment can prohibit the automatic stopping of the engine simply by changing the position at which the accelerator pedal 12 is depressed. Therefore, compared to a case in which a switch for prohibiting the automatic stopping of the engine 2 is provided on the instrument panel, the automatic stopping of the engine 2 can be prohibited with a simple operation while driving.

[0041] In addition, the control device for the hybrid vehicle according to this embodiment is able to more accurately detect the driver's intentions and prohibit the automatic stopping of the engine in situations where there is no need to depress the accelerator pedal 12 much by providing the contact sensor 14 at a position where the accelerator pedal 12 is not depressed.

[0042] In addition, the control device for the hybrid vehicle in this embodiment prohibits automatic stopping of the engine 2 while contact is detected by the contact sensor 14, and allows automatic stopping of the engine 2 while contact is not detected by the contact sensor 14.Therefore, while contact is detected by the contact sensor 14, automatic stopping of the engine 2 is prohibited assuming that the driver intends to prohibit automatic stopping of the engine 2, thereby making it possible to prohibit automatic stopping of the engine 2 in accordance with the driver's intention.

[0043] In addition, the control device for a hybrid vehicle in this embodiment can set an automatic stop prohibition state in which automatic stopping of the engine is prohibited until the hybrid vehicle 1 comes to a stop, thereby eliminating the need for the driver to continue to contact the contact sensor 14, thereby further improving operability.

[0044] Furthermore, since the control device for the hybrid vehicle in this embodiment can cancel the automatic stop prohibition state when the contact sensor 14 detects another contact during the automatic stop prohibition state, the engine 2 can be controlled in accordance with the driver's intentions even if the driver's intentions change.

[0045] In this embodiment, an example has been described in which the contact sensor 14 is configured using a piezoelectric element, but the contact sensor 14 may be configured using other components, such as a momentary type push button, as long as it detects contact with a part of the accelerator pedal 12.

[0046] Furthermore, the control device for the hybrid vehicle according to this embodiment may be provided with an optical sensor consisting of a light-emitting element and a light-receiving element, instead of the contact sensor 14. In this case, a light-emitting element is provided either above the accelerator pedal 12 or in front of the accelerator pedal 12, and a light-receiving element is provided on the other side. When the light emitted from the light-emitting element is no longer received by the light-receiving element, the ECU 11 determines that contact with a part of the accelerator pedal 12 has been detected, and prohibits the automatic stop of the engine 2.

[0047] In this embodiment, the condition for prohibiting automatic stopping of the engine 2 is that the contact sensor 14 detects contact, but the condition for prohibiting automatic stopping of the engine 2 may be, for example, that the contact sensor 14 detects contact and the accelerator opening at that time is equal to or smaller than a predetermined value. In this case, it is possible to reliably detect that the driver has deliberately moved his / her foot to the position of the contact sensor 14 when the driver is not depressing the accelerator pedal 12. This makes it possible to accurately grasp the driver's intention.

[0048] Furthermore, in order to prohibit the automatic stopping of the engine 2, the control device for the hybrid vehicle according to this embodiment only needs to be able to detect a slight change in the driver's driving operation, and may prohibit the automatic stopping of the engine 2 depending on, for example, the strength with which the driver grips the steering wheel (not shown).

[0049] Although an embodiment of the invention has been disclosed, it will be apparent to one of ordinary skill in the art that modifications may be made thereto without departing from the scope of the invention, and it is intended that all such modifications and equivalents be included in the following claims. [Explanation of symbols]

[0050] 1 Hybrid vehicles 2 Engine 4. High voltage motor (electric motor) 11 ECU (control unit) 12 Accelerator pedal 14 Contact Sensor

Claims

1. The engine, An electric motor; An accelerator pedal; A control device for a hybrid vehicle, which automatically stops the engine and transitions to a motor driving mode in which the vehicle runs on power output from the engine or the engine and the electric motor when an amount of depression of the accelerator pedal is equal to or less than a predetermined amount during hybrid driving in which the vehicle runs on power output from the engine or the engine and the electric motor, The accelerator pedal is provided with a sensor that detects contact with a part of the accelerator pedal, A control device for a hybrid vehicle, comprising: a control unit that inhibits an automatic stop of the engine when the contact is detected by the sensor.

2. 2. The control device for a hybrid vehicle according to claim 1, wherein the sensor is provided in front of the accelerator pedal.

3. 3. The control device for a hybrid vehicle according to claim 1, wherein the control unit prohibits automatic stopping of the engine while the contact is detected by the sensor, and allows automatic stopping of the engine while the contact is not detected by the sensor.

4. 4. The control device for a hybrid vehicle according to claim 1, wherein when the contact is detected by the sensor for a predetermined period of time or more while the hybrid vehicle is traveling, the control unit enters an automatic stop prohibition state in which automatic stopping of the engine is prohibited until the hybrid vehicle is stopped, even if the contact is no longer detected by the sensor.

5. 5. The control device for a hybrid vehicle according to claim 4, wherein the control unit cancels the automatic stop prohibition state when the contact is detected again by the sensor during the automatic stop prohibition state.

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