JP-7855897-B2 - Vehicle sound generation device

JP7855897B2JP 7855897 B2JP7855897 B2JP 7855897B2JP-7855897-B2

Inventors

三浦泰彦
石井秀和
阿草敬祐
武吉亨
佐々木健二

Assignees

マツダ株式会社

Dates

Publication Date: 20260511
Application Date: 20220330

Claims (6)

A vehicle sound generation device mounted on a vehicle that runs using an electric motor as a power source, A sound control unit configured to generate sound signals representing sound, A sound output unit that outputs sound corresponding to the sound signal generated by the sound control unit, The vehicle has an acceleration state detection unit that detects when the vehicle is in an accelerating state, When the sound control unit detects that the vehicle is in an accelerating state, it sets the time progression of the parameters of the sound signal and generates the sound signal based on the time progression of those parameters. The time progression of the parameters includes a repetition of a first trend and a second trend following the first trend, and in the time interval of change timings in which the first trend changes to the second trend , the time interval from the first change timing to the second change timing is set to twice the first time from when the vehicle is detected to be in an accelerating state to the first change timing , and the time interval from the second change timing to the third change timing is set to 2.5 times the first time . The first trend is a trend in which the parameter increases over time, and the second trend is a trend in which the parameter decreases over time . A sound generator for vehicles.
The aforementioned parameters include either or both frequency and sound pressure. The vehicle sound generating device according to claim 1.
The electric motor has a motor speed sensor that detects the rotation speed of the electric motor, If the sound control unit does not detect that the vehicle is in an accelerating state, it generates the sound signal based at least on the rotational speed of the electric motor. The vehicle sound generating device according to claim 1 or 2.
The vehicle has an accelerator opening sensor that detects the accelerator opening degree, The acceleration state detection unit detects that the vehicle is in an accelerating state when the accelerator opening increases, and the amount of increase from the start to the end of the increase in the accelerator opening is greater than or equal to a predetermined amount, and the accelerator opening at the end of the increase is greater than or equal to a predetermined opening. The vehicle sound generating device according to claim 1.
The sound control unit sets the time from the detection that the vehicle is in an accelerating state until the first trend changes to the second trend to a shorter duration, the larger the accelerator opening at the end of the increase in the accelerator opening, according to claim 4.
The sound control unit sets the time from the detection of the vehicle being in an accelerating state until the first trend changes to the second trend to the shorter the time from the start to the end of the increase in the accelerator opening, the shorter the time from the start to the end of the increase in the accelerator opening. This is the vehicle sound generation device according to claim 4 or 5.

Description

This invention relates to a vehicle sound generation device, and more particularly to a vehicle sound generation device that outputs a predetermined sound while the vehicle is in motion. Conventionally, technologies have been known that output simulated engine and motor sounds to the driver in response to vehicle operating conditions such as vehicle speed and driver operations such as accelerator pedal position. For example, the vehicle sound generation device described in Patent Document 1 outputs a synthesized sound containing multiple frequencies set to be proportional to the rotational speed of the electric motor. In response to an increase in motor torque, the increase in the output of low-frequency sounds is set to be greater than the increase in the output of high-frequency sounds. This allows the driver to easily recognize the strength of the vehicle's acceleration in response to accelerator pedal operation, thereby promoting accurate accelerator control. Japanese Patent Publication No. 2021-32972 This is an explanatory diagram of a vehicle sound generation device according to an embodiment of the present invention.This is a diagram showing the configuration of a vehicle sound generation device according to an embodiment of the present invention.This is a radar chart showing an example of experimental results related to the present invention.This is a flowchart of the sound generation process according to an embodiment of the present invention.This is a frequency map that defines the relationship between motor rotation speed and frequency according to an embodiment of the present invention.This is a sound pressure map that defines the relationship between motor rotation speed and sound pressure according to an embodiment of the present invention.This is a map that defines the time until the first trend change timing according to an embodiment of the present invention.This is a frequency map that defines the time progression of frequencies when a vehicle according to an embodiment of the present invention is in an accelerating state.This is a sound pressure map that defines the time progression of sound pressure when a vehicle according to an embodiment of the present invention is in an accelerating state. The embodiments of the present invention will be described below with reference to the attached drawings. <Configuration of a vehicle sound generation device> First, the configuration of the vehicle sound generation device of the present invention will be described with reference to Figures 1 and 2. Figure 1 is an explanatory diagram of the vehicle sound generation device, and Figure 2 is a configuration diagram of the vehicle sound generation device. As shown in Figures 1 and 2, the vehicle sound generation device 1 of this embodiment comprises a sound control device 10 mounted on the vehicle 2, a speaker 20 that outputs a predetermined sound to the driver inside the vehicle, and a group of various sensors 30 that detect the state of the vehicle 2. The vehicle 2 is an electric vehicle (EV) equipped with an electric motor 3 as a rotational power source. The sound control device 10 is a well-known computer-based controller that includes a circuit. The sound control device 10 comprises one or more processors as a central processing unit (CPU) for executing programs, a memory (storage unit 14) for storing various programs and databases, composed of, for example, RAM (Random Access Memory) and ROM (Read Only Memory), and data input/output devices for inputting and outputting electrical signals. The database in the memory unit 14 stores various maps used for generating sound signals. The sound control device 10 is connected to other in-vehicle devices via an in-vehicle communication line. The sound control device 10 is configured to output a sound signal Ss to the speaker 20 by having the processor execute a program based on various information from the sensor group 30. In this process, the processor of the sound control device 10 functions as a sound control unit 12 and an acceleration state detection unit 13, as will be described later. Speaker 20 is a sound output unit equipped with an amplifier. Speaker 20 receives a sound signal Ss from the sound control device 10, amplifies the sound signal Ss at a predetermined amplification factor, and outputs a sound (typically a synthesized sound) SC based on the sound signal Ss. Note that speaker 20 does not necessarily have to be located inside the vehicle cabin; it is sufficient that the driver can recognize the sound SC generated by speaker 20. The sensor group 30 includes a rotation speed sensor 31 for detecting the rotation speed of the electric motor 3, an accelerator opening sensor 32 for detecting the accelerator opening corresponding to the amount of operation of the accelerator pedal of the vehicle 2, and a motor torque sensor 33 for detecting the motor torque of the electric motor 3. These sensors 30 transmit signals S31, S32, and S33 indicating th