JP2011201520A - Sounding method from vehicle body of automobile - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve safety by informing a pedestrian of the presence of an automobile, by intentionally sounding from a vehicle body in low speed travel of a hybrid vehicle and an electric automobile.SOLUTION: This sounding method is characterized by intentionally sounding from the vehicle body in the low speed travel by installing a vibration actuator in part of the vehicle body of the hybrid vehicle and the electric automobile.

Description

  The present invention relates to a method for generating sound from a part of a vehicle body using a vibration actuator.

  In recent years, due to environmental problems and oil resource depletion problems, a hybrid vehicle that uses a drive system that uses a combination of a petroleum fuel engine and an electric motor, or an electric vehicle that uses a drive system that uses an electric motor alone, from an oil fuel engine that uses petroleum such as gasoline. Is commercially available. These vehicles have high fuel consumption efficiency, low emission of exhaust gas, environmental and resource saving aspects, and these vehicles have low noise due to running, the problems to the living environment are reduced, and the spread of the vehicles is progressing. Yes.

  As described in the background art, hybrid vehicles and electric vehicles have great advantages in resource saving and environmental improvement. However, since the driving noise has been reduced, the following new problems that have not existed in the conventional oil-fueled automobiles with driving noise have appeared.

  Hybrid cars and electric cars have low noise when traveling at low speeds of 20 km / h or less, places where pedestrians and cars are mixed, such as service areas such as expressways, narrow roads where pedestrians and cars approach, large stores In many parking lots, pedestrians are not aware of an approaching car, and there are many cases in which confirmations are delayed and accidents occur, and improvement of safety during low-speed driving has been an issue.

  The present invention relates to a sound generation method for informing a pedestrian of the presence of a vehicle and ensuring safety by intentionally sounding at the time of low speed traveling of a hybrid vehicle or an electric vehicle.

  Specifically, a vibration actuator made of a magnetostrictive element or the like is attached to a part of the body of a hybrid vehicle or an electric vehicle, for example, the headlight housing shown in FIG. 3, and an audio signal is added to the actuator to generate sound from the headlight. Is the method.

  Further, in order to make a pedestrian recognize the traveling state of the automobile, it is a method of controlling the driving of a vibration actuator in which the traveling speed of the automobile and sound generation are linked.

  By generating sound from the hybrid vehicle or electric vehicle that is running, it is possible for the pedestrian to recognize the running vehicle both visually and auditorily, thereby improving safety.

  Speakers are generally used to generate sound from horns and the like. Although the use of the speaker is simple, since an opening is required on the surface that emits sound, the mounting position is restricted and the degree of freedom in designing and designing the vehicle body is reduced. On the other hand, the present invention has an advantage that the surface of the attached portion becomes a so-called diaphragm for sound generation and generates sound, so there is no need to provide an opening, and the degree of freedom in designing and designing the vehicle body is increased. is there.

Example of actuator mounting position Actuator drive system block diagram Example of mounting the actuator to the headlight housing Example of actuator installation on the tail lamp housing Example of mounting an actuator on a bumper Example of mounting the actuator on the rearview mirror housing Playback frequency characteristics of headlight pronunciation Actuator drive control system block diagram Drive control flowchart

  In order to demonstrate the effect of the present invention, Examples 1 to 4 were performed using the following automobiles and vibration actuators.

Magnetostrictive element actuator: R12-23 (manufactured by GMM Tech)
Piezoelectric actuator: ASL170-C801NPOLF (NEC / Tokin)
Automobile: Prius (Toyota)

  An actuator is attached to a position not exposed to the surface of the vehicle body inside the vehicle body portion shown in FIG.

  The vehicle body part, the vibration actuator, and the attachment method of the vibration actuator shown in the embodiment are not limited to the embodiment, and the vehicle body part and attachment method that are most effective for improving safety are selected.

  Also, the sound signal applied to the actuator may be a sound that reliably informs safety and is not limited to a specific signal sound.

  Protrusion for mounting the actuator on the back side of the left and right headlight housings for the magnetostrictive actuator, the actuator is inserted into that part, and the bottom of the actuator is pressurized with screws, and the actuator is attached to produce sound effects I confirmed. (Figure 3)

  In the audibility test, it was confirmed that the pedestrian recognized the position of the car and improved safety even at a distance of 10 m or more.

  It is considered that the audible distance is 10 m or more because the sound wave generated is close to a plane wave because the shape of the front surface of the headlight is planar, and the distance attenuation of the sound is small.

  It has been confirmed that the present invention is a technique that can generate a sound volume that can be used as an alarm sound by optimizing the attachment site, the housing, and the vibration actuator.

  Multilayer piezoelectric actuators were attached to the back side of the left and right tail lamp housings to confirm the effect of sound generation. The method of attachment is the same as in the first embodiment. (Fig. 4)

  Similar to Example 1, the laminated piezoelectric actuator produced a sound that could improve safety, and it was confirmed that the method of the present invention was possible using any type of vibration actuator.

  Magnetostrictive actuators were installed on the back and left and right sides of the bumpers on the front and rear of the car body to confirm the sound generation effect. The attachment was performed in the same manner as in Example 1. (Fig. 5)

  As in Example 1, the effect of sufficiently improving safety was confirmed.

  In addition, since the bumper is made of a softer material than the light and lamp housings of Examples 1 and 2, the generated sound was slightly shifted to the low frequency side.

  It can be understood that the sound quality can be changed by changing the material of the portion to be vibrated in this way, the sound quality most suitable for human hearing can be selected, and the safety can be improved.

  Magnetostrictive actuators were installed inside the left and right rearview mirrors to confirm the effect of pronunciation. The attachment was performed in the same manner as in Example 1. (Fig. 6)

  Compared with Examples 1 to 3, since the rearview mirror was small, the sound pressure generated was slightly felt, but it was confirmed that the sound volume was sufficient for ensuring safety.

  In addition, since the actuator is small, it can be mounted inside a small part such as a rearview mirror, and if the mounting part and the actuator are optimized, there is a possibility of further miniaturization and freedom of sound generation method. It can be judged that the degree increases.

  The headlight of Example 1 was removed, and the reproduction frequency characteristics produced in an anechoic room were measured.

  Measurement conditions: Input 8Ω, 1W, 1m

  The reproduction sound frequency is 350 Hz to 12 Kz, and it has been confirmed that the frequency can be selected to improve the safety. (Fig. 7)

  By optimizing the shape of the headlight and the actuator, it is possible to further improve the reproduction sound frequency characteristics.

  In Examples 1 to 4, the effect of the present invention was confirmed by the actuator drive system shown in FIG. 2, but an actuator drive system necessary for putting the present invention to practical use in a hybrid vehicle or an electric vehicle was examined.

  The actuator drive system (Fig. 8) and CPU flow chart (Fig. 8) are studied with the assumption that the pronunciation is automatically activated at a speed that complies with laws and regulations, for example, 20 km / h or less, and that the driver temporarily stops. It was found that the combined drive device of 9) is effective.

  In the future automobile industry, it is highly likely to be used to improve the safety of hybrid vehicles and electric vehicles, which are expected to spread widely.

1: Vibration actuator 2: Mounting position of vibration actuator on headlight 3: Mounting position of vibration actuator on tail lamp 4: Mounting position of vibration actuator on bumper 5: Mounting position of vibration actuator on rearview mirror 6: Headlight Housing 7: Pressure screw to vibration actuator 8: Mounting protrusion of vibration actuator 9: Tail lamp housing 10: Multilayer piezoelectric actuator 11: Mirror

Claims (9)

  A pronunciation method characterized in that a vibration actuator is attached to a part of a car body of an automobile.   The automobile according to claim 1 is a hybrid vehicle and an electric vehicle using both a petroleum fuel engine and an electric drive.   A part of the vehicle body of claim 1 is a headlight and tail lamp housing.   A part of the vehicle body according to claim 1 is a front bumper and a rear bumper.   A part of the vehicle body according to claim 1 is a left and right rearview mirror.   The vibration actuator according to claim 1 is an actuator composed of a magnetostrictive element.   The vibration actuator according to claim 1 is an actuator made of a piezoelectric element.   The vibration actuator according to claim 1 is an electric actuator composed of a coil and a magnet.   The input device for driving the vibration actuator according to claim 1 is a controllable device linked to the traveling speed of the automobile.

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