Display control device

Abstract

To display a state where a brake light is turned on in a deceleration region to a driver driving an electric vehicle.SOLUTION: A display control device includes: an acquisition part for acquiring current vehicle speed traveling of an electric vehicle; a state detection part for detecting the state of a drive motor; and a display control part for performing display control displaying a lighting threshold indicating a lighting state of a brake light, on the basis of the vehicle speed and the state of the drive motor, when the deceleration of the electric vehicle is lower than a predetermined threshold.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] This embodiment relates to a display control device.

Background Art

[0002] In an electric vehicle, when strongly decelerating by turning off the accelerator pedal, there is a technique of turning on a brake lamp mounted on the vehicle according to regulations.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, since it is difficult to numerically capture the deceleration rate in terms of human perception, for example, when the accelerator is released (turned off) while driving at high speed on a highway, the brake lamp may turn on contrary to the driver's intention due to the deceleration of the electric vehicle. However, since the driver cannot grasp the lighting state unless the brake lamp turns on once, there is room for further improvement.

[0005] An object of the present invention is to provide a display control device that can display the lighting state of a brake lamp in a deceleration region to a driver operating an electric vehicle.

Means for Solving the Problems

[0006] To achieve the above objective, the display control device according to the present invention includes an acquisition unit for acquiring the current vehicle speed of the electric vehicle, a state detection unit for detecting the state of the drive motor, and a unit for detecting when the deceleration of the electric vehicle reaches a predetermined threshold. Exceed The system includes a display control unit that performs display control to display an illumination threshold indicating the illumination state of the brake lights based on the vehicle speed and the state of the drive motor.

[0007] With this configuration, the display control device can output a lighting threshold to the display device 52, for example. This allows the driver to understand the lighting threshold (lighting timing) for the brake lights to illuminate, so that if the deceleration falls below a predetermined threshold, the brake lights will not illuminate. Therefore, even if the driver eases off the accelerator while driving, for example, the brake lights will not illuminate against the driver's will.

[0008] Furthermore, the display control unit may also display the vehicle speed acquired by the acquisition unit. In addition, the display control unit may display a deactivation threshold indicating the deactivation state of the brake lights based on the vehicle speed and the state of the drive motor.

[0009] Furthermore, the acquisition unit may acquire the remaining battery capacity of the drive battery, and the display control unit may display a starting threshold indicating the engine starting state based on the remaining battery capacity of the drive battery acquired by the acquisition unit.

[0010] With this configuration, the display control device can output, for example, vehicle speed, illumination threshold, extinguishing threshold, and starting threshold to the display device 52. This allows the driver to understand the illumination threshold (illumination timing) and extinguishing threshold (extinguishing timing) of the brake lights, and thus understand when the brake lights illuminate and extinguish. In addition, by understanding the starting threshold (starting timing) of the engine 11, the driver can suppress the power consumption of the drive battery 14 and better understand the fuel efficiency and energy consumption of the electric vehicle 1. [Effects of the Invention]

[0011] According to the present invention, it is possible to display to a driver operating an electric vehicle the state in which the brake lights are illuminated in the deceleration region. [Brief explanation of the drawing]

[0012] [Figure 1] Figure 1 is a block diagram showing an example of the configuration of an electric vehicle according to this embodiment. [Figure 2] Figure 2 is a block diagram showing an example of the functional configuration of the display control device according to this embodiment. [Figure 3] Figure 3 is a diagram illustrating an example of the control process in the display control device according to this embodiment. [Figure 4] Figure 4 is a schematic diagram showing an example of the output of the display control device according to this embodiment. [Figure 5] Figure 5 is a flowchart showing an example of the processing of the display control device according to this embodiment. [Figure 6] Figure 6 is a schematic diagram showing an example of the output of a display control device related to a modified example. [Figure 7] Figure 7 is a flowchart showing an example of processing in a modified display control device. [Modes for carrying out the invention]

[0013] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0014] <Electric Vehicles> Figure 1 is a block diagram showing the configuration of an electric vehicle 1 according to one embodiment of the present invention.

[0015] The electric vehicle 1 is equipped with a series hybrid system 2. The hybrid system 2 includes an engine (ENG) 11, a generator motor (MG1) 12, a drive motor (MG2) 13, a drive battery 14, and a PCU (Power Control Unit) 15.

[0016] The engine 11 is, for example, a gasoline engine or a diesel engine. An engine output gear 22 is provided on a crankshaft 21 of the engine 11 so as to rotate integrally with the crankshaft 21.

[0017] The power generation motor 12 is, for example, a permanent magnet synchronous motor. A power generation motor gear 24 is provided on a rotating shaft 23 of the power generation motor 12 so as to rotate integrally. The power generation motor gear 24 meshes with the engine output gear 22. The power generation motor 12 is used as a starter motor for cranking the engine 11 when the engine 11 stops. After the engine 11 starts, the power generation motor 12 functions as a generator for converting the power of the engine 11 into electric power.

[0018] The drive motor 13 is, for example, a permanent magnet synchronous motor larger than the power generation motor 12. A motor output gear 26 is provided on a rotating shaft 25 of the drive motor 13 so as to rotate integrally with the rotating shaft 25.

[0019] The motor output gear 26 is coupled to a power transmission mechanism 3 mounted on the electric vehicle 1. The power transmission mechanism 3 includes a countershaft 31, a counter gear 32, an output gear 33, and a differential gear 34.

[0020] The countershaft 31 is provided parallel to the rotating shaft 25 of the drive motor 13. The counter gear 32 and the output gear 33 are provided on the countershaft 31 so as to rotate integrally. The output gear 33 meshes with a ring gear 35 of the differential gear 34. The motor output gear 26 meshes with the counter gear 32.

[0021] The power from the drive motor 13 is transmitted to the differential gear 34 via the motor output gear 26, counter gear 32, and output gear 33. The power transmitted to the differential gear 34 is then transmitted to the left and right drive wheels 5 via the left and right drive shafts 4 of the electric vehicle 1. As a result, the left and right drive wheels 5 rotate, and the electric vehicle 1 moves forward or backward.

[0022] The drive battery 14 is a battery pack made up of multiple secondary batteries (for example, lithium-ion batteries). The drive battery 14 outputs DC power of approximately 200 to 350 volts.

[0023] The PCU15 is a unit for controlling the drive of the generator motor 12 and the drive motor 13, and includes a first inverter (MG1INV) 41, a second inverter (MG2INV) 42, and a boost converter (BstCONV) 43.

[0024] During acceleration of the electric vehicle 1, the drive motor 13 is operated to generate power for acceleration. At this time, the DC power output from the drive battery 14 is boosted as needed by the boost converter 43, the DC power output from the boost converter 43 is converted to AC power by the second inverter 42, and this AC power is supplied to the drive motor 13. This consumes the power of the drive battery 14.

[0025] Furthermore, when the engine 11 is started, the DC power output from the drive battery 14 is boosted by the boost converter 43, and the boosted DC power is converted into AC power by the first inverter 41, and the AC power is supplied to the generator motor 12. As a result, the generator motor 12 is driven into motoring mode, and the engine 11 is motorized by the generator motor 12. This motoring causes the crankshaft 21 of the engine 11 to rotate, and when the rotational speed rises to the rotational speed required for starting, the spark plug of the engine 11 sparks, and the engine 11 starts.

[0026] With the engine 11 running, the generator motor 12 is operated to generate power, thereby generating alternating current (AC) power. The AC power generated by the generator motor 12 is converted to DC power by the first inverter 41. Then, the DC power output from the first inverter 41 is converted to AC power by the second inverter 42, and the AC power is supplied to the drive motor 13.

[0027] Furthermore, when power supply to the drive motor 13 is not required, the DC power output from the first inverter 41 is stepped down by the boost converter 43, and the stepped-down DC power is supplied to the drive battery 14, thereby charging the drive battery 14.

[0028] When the electric vehicle 1 is decelerating, the drive motor 13 is regenerated, and the power transmitted from the drive wheels 5 to the drive motor 13 is converted into alternating current (AC) power. At this time, the drive motor 13 becomes a resistance in the drive system, and this resistance acts as a braking force (regenerative braking force) that brakes the electric vehicle 1. The AC power generated by the drive motor 13 is converted into DC power by the second inverter 42. Then, the DC power output from the second inverter 42 is stepped down by the boost converter 43, and the stepped-down DC power is supplied to the drive battery 14, thereby charging the drive battery 14.

[0029] Furthermore, the electric vehicle 1 is equipped with an ECU (Electronic Control Unit) 6, which includes a microcontroller unit (microcomputer) 51. The microcontroller 51 incorporates, for example, a CPU (Central Processing Unit), non-volatile memory such as flash memory, and volatile memory such as DRAM (Dynamic Random Access Memory).

[0030] Although Figure 1 shows only one ECU6, the electric vehicle 1 is equipped with multiple ECUs, each with a similar configuration to ECU6, to control various parts of the vehicle. These multiple ECUs, including ECU6, are connected to enable bidirectional communication using the CAN (Controller Area Network) communication protocol.

[0031] The ECU 6 determines the amount of accelerator pedal operation by the driver based on the detection results of the accelerator sensor 7, which will be described later. Based on the amount of accelerator pedal operation, the ECU 6 sets the engine torque requirement and outputs a control signal for the engine torque requirement to the PCU 15.

[0032] When the ECU 6 is instructed to generate regenerative torque, if the deceleration generated in the electric vehicle 1 exceeds a predetermined threshold, it illuminates the brake lights 9. This notifies the driver of the following vehicle that the electric vehicle 1 is decelerating. The ECU 6 is an example of a display control device.

[0033] The accelerator sensor 7 outputs a detection signal corresponding to the amount of pressure applied to the accelerator pedal by the driver. The accelerator sensor 7 is connected to the ECU 6 for communication and outputs the detection signal to the ECU 6.

[0034] The vehicle speed sensor 8 is installed, for example, near the wheels of the electric vehicle 1 and generates a vehicle speed pulse indicating the rotational speed or rotational number of the wheel. The vehicle speed sensor 8 is connected to the ECU 6 in a communicative manner and outputs the generated vehicle speed pulse to the ECU 6.

[0035] The brake light 9 is activated when the ECU 6 instructs the generation of regenerative torque, and the deceleration generated in the electric vehicle 1 is predetermined. threshold If the value exceeds a certain level, the light will turn on.

[0036] A display device 52 is installed inside the vehicle cabin of the electric vehicle 1. The display device 52 may be, for example, a touch panel. The display device 52 may also be configured by attaching a pressure-sensitive or capacitive transparent film switch to a liquid crystal display, and may be provided as a multi-information display that displays various information such as vehicle setting information for the electric vehicle 1, as well as navigation information and music information.

[0037] (Functional Configuration) Next, the functional configuration of the display control device according to this embodiment will be described with reference to Figure 2. Figure 2 is a block diagram showing an example of the functional configuration of the display control device.

[0038] The ECU6 includes an acquisition unit 61, a deceleration determination unit 62, a state detection unit 63, a threshold calculation unit 64, and a display control unit 65. However, the functions of the ECU6 are not limited to these.

[0039] The acquisition unit 61 acquires the amount of operation of the driver's accelerator pedal. Specifically, the acquisition unit 61 works in cooperation with the accelerator sensor 7 to acquire the amount of operation of the accelerator pedal.

[0040] Furthermore, the acquisition unit 61 acquires the current vehicle speed. Specifically, the acquisition unit 61 works in cooperation with the vehicle speed sensor 8 to acquire the current vehicle speed of the electric vehicle 1.

[0041] The deceleration determination unit 62 determines whether or not a predetermined deceleration has been exceeded. Specifically, the deceleration determination unit 62 calculates the deceleration from the vehicle speed acquired by the acquisition unit 61 and determines whether or not a predetermined deceleration has been exceeded. The predetermined deceleration is a predetermined deceleration, for example, the deceleration at which the brake lights 9 need to illuminate is a value stipulated by law. Alternatively, the deceleration of the electric vehicle 1 may be determined by equipping the electric vehicle 1 with a known acceleration sensor and detecting the deceleration from the detection result of the acceleration sensor.

[0042] The state detection unit 63 detects the state of the drive motor 13. Specifically, the state detection unit 63 works in cooperation with the drive motor 13 to detect the state of the drive motor 13. The state of the drive motor 13 includes, for example, the state in which the drive motor 13 is being driven and power is being consumed from the drive battery 14, or the state in which the drive motor 13 is being regenerated and power is being charged to the drive battery 14.

[0043] The threshold calculation unit 64 calculates the illumination threshold at which the brake light 9 illuminates. Specifically, the threshold calculation unit 64 calculates the illumination threshold at which the brake light 9 illuminates based on the vehicle speed acquired by the acquisition unit 61, which corresponds to the state of the drive motor 13 detected by the state detection unit 63.

[0044] Here, the illumination threshold will be explained using Figure 3. Figure 3 is a diagram illustrating an example of control processing in the display control device. In Figure 3, the vertical axis represents the torque [N / m] of the drive motor 13, and the horizontal axis represents the vehicle speed [km / h] of the electric vehicle 1. When the torque of the drive motor 13 shows a positive value, it indicates that the drive motor 13 is operating under power. When the torque of the drive motor 13 shows a negative value, it indicates that the drive motor 13 is operating under regenerative braking.

[0045] Figure 3 is a line graph showing the torque of the drive motor 13 in relation to the on / off state of the brake light 9 of the electric vehicle 1. Specifically, it shows the relationship between the torque of the drive motor 13 and the vehicle speed, indicating the on / off threshold for the brake light 9. Graph G71 is a graph of the on / off threshold for the brake light 9 to turn on, and graph G72 is a graph of the off / off threshold for the brake light 9 to turn off.

[0046] For example, at vehicle speed A, the intersection with graph G71 represents the illumination threshold X. Since graph G71 is a graph of the illumination threshold at which the brake light 9 illuminates, at vehicle speed A, when the speed falls below illumination threshold X, the brake light 9 transitions from the off state to the on state.

[0047] Furthermore, for example, at vehicle speed A, the intersection with graph 72 represents the deactivation threshold Y. Since graph G72 is the graph of the deactivation threshold at which the brake light 9 turns off, at vehicle speed A, when the deactivation threshold Y is exceeded, the brake light 9 transitions from the illuminated state to the deactivated state.

[0048] The reason why the thresholds are set as an on-light threshold X and an off-light threshold Y is that, for example, if the on-light threshold X and the off-light threshold Y were the same, the brake light 9 would frequently switch between on and off, making it difficult for the driver or following vehicles to perceive it. Therefore, separate thresholds are set for the on-light threshold X and the off-light threshold Y.

[0049] Returning to Figure 2, the display control unit 65 performs display control on the display device 52 to display (hereinafter also referred to as outputting) the vehicle speed and the illumination threshold X. Specifically, the display control unit 66 performs display control on the display device 52 to display the vehicle speed acquired by the acquisition unit 61 and the illumination threshold X calculated by the threshold calculation unit 64.

[0050] Here, we will explain the output content of the display control unit 65 using Figure 4. Figure 4 is a diagram illustrating an example of the content displayed on the display device 52.

[0051] The diagram shown in Figure 4 is displayed on the display device 52, and the shape of the display is a bar. The bar also displays three modes: "CHARGE," "ECO," and "POWER," each indicating the status of the drive battery 14.

[0052] Specifically, "CHARGE" is the state in which the drive motor 13 is rotating and power is being charged to the drive battery 14. "ECO" is the state in which the drive motor 13 is not operating and power is being consumed from the drive battery 14. "POWER" is the state in which the drive motor 13 is operating in power mode and power is being consumed from the drive battery 14.

[0053] The display control unit 65 outputs the vehicle speed A acquired by the acquisition unit 61 and the illumination threshold X calculated by the threshold calculation unit 64 superimposed on the bar shape shown in Figure 4. Arrow M1 represents the range in which the vehicle speed A moves, and arrow M2 represents the range in which the illumination threshold X moves.

[0054] Next, the processing flow controlled by the display control device will be explained using Figure 5. Figure 5 is a flowchart showing an example of the processing of the display control device according to this embodiment.

[0055] The acquisition unit 61 acquires the current vehicle speed A (step S101). Next, the deceleration determination unit 62 determines whether or not a predetermined deceleration has been exceeded (step S102). If the deceleration determination unit 62 determines that the predetermined deceleration has not been exceeded (step S102: No), this process ends. On the other hand, if the deceleration determination unit 62 determines that the predetermined deceleration has been exceeded (step S102: Yes), the process proceeds to step S103.

[0056] The state detection unit 63 detects the state of the drive motor 13 (step S103). Next, the threshold calculation unit 64 calculates the illumination threshold X at which the brake light 9 illuminates (step S104). The display control unit 65 controls the display device 52 to display the vehicle speed A and the illumination threshold X (see Figure 4) (step S105). When step S105 is completed, the process returns to step S101 and continues until the electric vehicle 1 falls below a predetermined deceleration.

[0057] Furthermore, when the electric vehicle 1 falls below a predetermined deceleration, the display of the illumination threshold X output by the display control unit 65 disappears. In other words, when the brake light 9 is illuminated, the display of the illumination threshold X output by the display control unit 65 disappears.

[0058] (Effects of this embodiment) As described above, the display control device according to this embodiment determines when the deceleration of the electric vehicle 1 reaches a predetermined threshold. ExceedBased on the vehicle speed A and the state of the drive motor 13, the display control device displays the illumination threshold X indicating the illumination state of the brake lights 9. In addition, the display control device according to this embodiment may display the current vehicle speed A in conjunction with the illumination threshold X indicating the illumination state of the brake lights 9.

[0059] Therefore, according to the present invention, the display control device can output the vehicle speed A and the illumination threshold X to the display device 52. As a result, the driver can understand the illumination threshold X (illumination timing) at which the brake light 9 illuminates, and if the deceleration falls below a predetermined threshold, the brake light 9 will not illuminate. Consequently, even if the driver eases off the accelerator while driving, for example, the brake light 9 will not illuminate against the driver's will. Furthermore, if the brake light 9 does not illuminate, it will also lead to a reduction in the power consumption of the brake light 9.

[0060] (modified version) The differences between the modified display control device and the display control device according to the above embodiment will be explained. In the above embodiment, the display control unit 65 determines when the deceleration reaches a predetermined threshold. Exceed The above describes a configuration in which the illumination threshold X indicating the illuminated state of the brake light 9 is displayed based on the vehicle speed A and the state of the drive motor 13. In this modified example, the display control unit 65 displays the illumination threshold X indicating the illuminated state of the brake light 9, and then further displays the deactivation threshold indicating the deactivation state of the brake light 9.

[0061] For example, the display control unit 65 displays an illumination threshold X indicating the illuminated state of the brake light 9, and then displays an illumination threshold indicating the unilluminated state of the brake light 9. Specifically, the threshold calculation unit 64 calculates an illumination threshold for when the brake light 9 is turned off, based on the vehicle speed acquired by the acquisition unit 61, which corresponds to the state of the drive motor 13 detected by the state detection unit 63. The display control unit 65 then displays the illumination threshold calculated by the threshold calculation unit 64, indicating the unilluminated state of the brake light 9.

[0062] Furthermore, for example, the display control unit 65 may display a starting threshold indicating the engine 11's starting state based on the remaining battery capacity of the drive battery 14 acquired by the acquisition unit 61. Specifically, the threshold calculation unit 64 calculates a starting threshold indicating the engine 11's starting state based on the remaining battery capacity of the drive battery 14 acquired by the acquisition unit 61, which corresponds to the state of the drive motor 13 detected by the state detection unit 63. The display control unit 65 then displays the starting threshold indicating the engine 11's starting state, which was calculated by the threshold calculation unit 64. The display control unit 65 may also display the starting threshold indicating the engine 11's starting state (at the same time as displaying the lighting threshold X) in conjunction with the lighting threshold X indicating the brake light 9's illumination state.

[0063] Here, using Figure 6, we will explain the output content of the display control unit 65 in the modified example. Figure 6 is a diagram illustrating an example of the content displayed on the display device 52.

[0064] The diagram in Figure 6 shows that, in addition to the content displayed in Figure 4 described above, the display control unit 65 outputs the off-light threshold Y and start-up threshold Z calculated by the threshold calculation unit 64 superimposed on the bar shape shown in Figure 6. Furthermore, arrow M3 indicates the range in which the off-light threshold Y moves, and arrow M4 indicates the range in which the start-up threshold Z moves.

[0065] Next, the processing flow of the display control device will be explained using Figure 7. Figure 7 is a flowchart showing an example of the processing of the display control device according to a modified example. Steps S201 to S205 correspond to the contents of steps S101 to S105 described in Figure 5. In this process, it is assumed that the acquisition unit 61 has acquired the remaining battery capacity of the drive battery 14 in advance.

[0066] The threshold calculation unit 64 calculates a deactivation threshold Y for when the brake light 9 turns off, based on the vehicle speed A acquired by the acquisition unit 61, which corresponds to the state of the drive motor 13 detected by the state detection unit 63 (step S206). Subsequently, the threshold calculation unit 64 calculates a starting threshold Z for when the engine 11 starts, based on the remaining battery capacity of the drive battery 14 acquired by the acquisition unit 61, which corresponds to the state of the drive motor 13 detected by the state detection unit 63 (step S207).

[0067] Next, the display control unit 65 performs display control on the display device 52 to display the off threshold Y and the start threshold Z (see Figure 6) (step S208). When step S208 is completed, the process returns to step S201 and continues until the electric vehicle 1 falls below a predetermined deceleration. When the electric vehicle 1 falls below the predetermined deceleration, the displays of the on threshold X and off threshold Y output by the display control unit 65 disappear.

[0068] As described above, the display control device according to this embodiment displays an illumination threshold X indicating the illuminated state of the brake light 9, and then displays an extinguishing threshold Y indicating the extinguishing state of the brake light 9. The display control device also displays a starting threshold Z indicating the starting state of the engine 11 based on the remaining battery charge of the drive battery 14.

[0069] Therefore, according to the present invention, the display control device can output the vehicle speed A, the illumination threshold X, the extinguishing threshold Y, and the starting threshold Z to the display device 52. The driver can understand the illumination threshold X (illumination timing) for when the brake light 9 illuminates and the extinguishing threshold Y (extinguishing timing) for when it extinguishing, and thus understand the timing of when the brake light 9 illuminates / extinguishes. In addition, by understanding the starting threshold Z (starting timing) for when the engine 11 starts, the driver can suppress the power consumption of the drive battery 14 and better understand the fuel efficiency and electric power consumption of the electric vehicle 1.

[0070] Furthermore, since the vehicle speed A, illumination threshold X, deactivation threshold Y, and starting threshold Z are displayed on the display device 52, the driver can grasp the vehicle's status at once, thereby reducing the number of times the driver needs to shift their gaze.

[0071] In the above embodiment, the shape of the display shown on the display device 52 was described as a bar shape, but it is not limited to this. The shape of the display may be, for example, a circle, and the display control may be performed to select between a bar shape and a circle shape according to the driver's preference.

[0072] While several embodiments of the present invention have been described, these embodiments are presented as examples only and are not intended to limit the scope of the invention. These novel embodiments can be carried out in a variety of other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their variations are included in the scope and spirit of the invention, as well as in the claims of the invention and its equivalents. [Explanation of Symbols]

[0073] 1. Electric Vehicle 2 Hybrid System 6 ECU 9 Brake lights 11 Engine 13 Drive motor 14. Power Battery 61 Acquisition Department 62 Deceleration judgment section 63 State detection unit 64 Threshold Calculation Unit 65 Display Control Unit

Claims

1. An acquisition unit that acquires the current vehicle speed of the electric vehicle, A state detection unit that detects the state of the drive motor, When the deceleration of the electric vehicle exceeds a predetermined threshold, a display control unit performs display control to display an illumination threshold indicating the illumination state of the brake lights based on the vehicle speed and the state of the drive motor. A display control device equipped with the following features.

2. The display control unit performs display control to further display the vehicle speed acquired by the acquisition unit. The display control device according to claim 1.

3. The display control unit performs display control to display an off threshold indicating the off state of the brake light based on the vehicle speed and the state of the drive motor. The display control device according to claim 1 or 2.

4. The acquisition unit further acquires the remaining battery capacity of the drive battery, The display control unit performs display control to display a starting threshold indicating the engine starting status based on the remaining battery capacity of the drive battery acquired by the acquisition unit. The display control device according to claim 3.

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