JP5853584B2 - Vehicle presence notification system - Google Patents

Description

  The present invention relates to a presence notification system that is provided in a vehicle using an electric motor as a power source and emits a notification sound around the vehicle.

  A vehicle using an electric motor as a power source such as a hybrid vehicle, an electric vehicle, or a fuel cell vehicle has a problem that it is difficult for a pedestrian to notice the presence or approach of the vehicle because the running sound is quiet. In order to solve the problem of running noise that is too quiet and to ensure the safety of pedestrians, various techniques have been proposed to notify the surrounding pedestrians of the presence of a vehicle by generating a pseudo engine sound according to the running speed of the vehicle. (For example, refer to Patent Documents 1 and 2.)

  However, since the pseudo engine sound is not the original sound of a vehicle running with an electric motor, it is uncomfortable for the surrounding pedestrians and the drivers / passengers in the vehicle, and the speed of the vehicle increases and the sound of the original motor etc. When becomes larger, the sound becomes more uncomfortable when combined with the pseudo engine sound. It has also been proposed to mute the engine sound above a specified speed, but the sounds at low speed and high speed are completely different, so it is still uncomfortable and the driver / passenger is conscious of the vehicle speed. This will cause a decrease in comfort.

JP-A-7-32948 JP-A-5-208636

  Therefore, in view of the above-mentioned situation, the present invention intends to solve the problem of generating a notification sound around a quiet vehicle such as a hybrid vehicle, an electric vehicle, a fuel cell vehicle, etc. Providing a presence notification system that can increase the safety by notifying the approach and can maintain the comfort of the vehicle without impairing the surrounding pedestrians, drivers and passengers in the vehicle It is in.

In order to solve the above-mentioned problem, the present invention is a presence notification system provided in a vehicle that includes an electric motor as a power source and uses an inverter in a drive circuit that drives the electric motor. A contact pickup device that is attached to the inverter and captures vibration of the casing of the inverter and converts it into an electrical signal, an amplifier device that amplifies the electrical signal output from the contact pickup device, and an electrical signal output from the amplifier device And a notification sound generating device for outputting sound around the vehicle based on the above.

  Here, it is preferable to provide a control means for controlling the operation of the amplifier device based on a change in the frequency of the electrical signal output from the contact pickup device. In particular, the control means has the frequency set to a predetermined value. It is preferable to stop the output of the amplifier device when it exceeds.

Further, the notification sound generating device is attached to a body structural member that can be seen from the periphery of a vehicle, and includes a vibrator that converts an electric signal output from the amplifier device into mechanical vibration, and the vibrator is mechanical vibration. It is preferable that a notification sound is emitted around the vehicle using the body component member to which the vibrator is attached as a diaphragm by outputting

  The contact pickup device is preferably a bone conduction pickup microphone.

  Further, as the vehicle, a hybrid vehicle, an electric vehicle, and a fuel cell vehicle are preferable.

  According to the presence notification system of the present invention as described above, the contact pickup device captures the casing vibration of the inverter and converts it into an electrical signal, which is amplified by the amplifier device and emitted as a notification sound. Due to the inverter sound, the surrounding pedestrians can be notified of the approach of the vehicle without a sense of incongruity, and the inverter sound, unlike motors, emits a vibration sound even when the vehicle is stopped due to a signal, etc. By amplifying this, the inverter sound can be used as a notification sound even when stopped. Therefore, it is not necessary to provide a reproducing means for storing / reproducing the pseudo sound data as in the prior art, it is not necessary to modulate a special sound frequency, and it can be easily installed even after retrofitting.

  Also, for the driver / passenger in the car, the original inverter sound and the notification sound are assimilated, there is no sense of incongruity, and it does not bother at all. Furthermore, when setting to mute at a predetermined speed or higher However, since it is the same inverter sound, the change is hardly felt before and after mute, and therefore the inconvenience that the driver and passengers in the vehicle are conscious of the vehicle speed and the comfort is reduced can be avoided. it can.

  In addition, since the control means for controlling the operation of the amplifier device based on the change in the frequency of the electrical signal output from the contact pickup device is provided, based on the frequency of the inverter vibration that increases as the vehicle speed increases, For example, it is possible to control the amount of amplification by the amplifier device to be smaller as the speed increases and the frequency increases, or to stop the amplifier output at a predetermined frequency or more without being connected to the vehicle speed sensor. When the output of the notification sound is controlled in accordance with the speed of the vehicle, the system of the present invention can be easily attached to the vehicle, particularly retrofitted, and the system can be easily handled.

  Further, since the control means controls to stop the output of the amplifier device when the frequency of electrical vibration output from the contact pickup device, that is, the inverter vibration frequency exceeds a predetermined value, the vehicle speed sensor is used as described above. Control can be easily performed to mute the notification sound when the speed of the vehicle exceeds a certain level without connection.

The notification sound generating device is attached to a body structural member that can be seen from the periphery of a vehicle, and includes a vibrator that converts an electrical signal output from the amplifier device into mechanical vibration, and the vibrator outputs mechanical vibration. As a result, a notification sound is emitted around the vehicle using the body component to which the vibrator is attached as a diaphragm, so that waterproof and dustproof measures are not required compared to conventional cone type speakers, and the installation location is selected. It can be installed easily and the cost can be reduced.

Explanatory drawing which shows the vehicle which attached the presence alerting | reporting system which concerns on typical embodiment of this invention. Explanatory drawing which shows the state which attached the vibration unit to the bumper of the vehicle. The block diagram which similarly shows the whole structure of a presence alerting | reporting system. The block diagram which similarly shows the structure of the notification sound generator of a presence notification system. The perspective view which similarly shows a vibration unit. Sectional drawing which similarly shows the attachment structure of a vibration unit.

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

  As shown in FIG. 1, the presence notification system S of the present invention includes an electric motor M as a power source such as a hybrid vehicle, an electric vehicle, and a fuel cell vehicle, and uses an inverter I for a drive circuit that drives the electric motor M. A contact pickup device 3 that is provided in the vehicle C and that attaches to the casing of the inverter I to capture the vibration and converts it into an electrical signal, and amplifies the electrical signal output from the contact pickup device 3 And a notification sound generating device 2 that outputs a sound around the vehicle based on the electrical signal output from the amplifier device 5.

  The contact pickup device 3 inputs vibration by contact, converts it into an electrical signal, and outputs it. For example, a bone conduction pickup microphone is preferably used. In the present invention, the housing vibration of the inverter I is acquired by the contact pickup device 3 as described above, and this is amplified and used as a notification sound. Therefore, the sound of the inverter I emitted from the vehicle body is used as the presence notification sound. It is possible to notify surrounding pedestrians and the like with a natural sound as an approaching sound, and can be used as a natural and uncomfortable sound for the driver and passengers. Therefore, it is not necessary to provide a reproducing means for storing / reproducing the pseudo sound data as in the conventional proposal, and it is not necessary to modulate a special sound frequency, and it can be easily installed even after retrofitting. Can be provided as a system.

  In this example, as shown in FIG. 3, the amplifier device 5 and the CPU (central processing unit) that controls the operation of the amplifier device 5 based on the change in the frequency of the electrical signal output from the contact pickup device 3 are included. The control means 4 is accommodated in a control box 6 in the vehicle. The amount of amplification by the amplifier device 5 is set so that, for example, about 50 dB can be secured within a range of 2 m ahead even when the frequency at low speed is low. The control means 4 preferably stops the output of the amplifier device 5 when the frequency exceeds a predetermined value.

  Of course, the control by the control means 4 can be performed by other control methods besides the above-described control. For example, based on a signal from a vehicle speed sensor of the vehicle C, control is performed to generate a sound at a low speed of a predetermined speed (for example, 20 km / h) or less, and the amplified amount of the reproduced acoustic signal is reduced as the speed increases. Control can also be performed. However, by controlling the operation of the amplifier device 5 based on the frequency value as described above, connection with the vehicle speed sensor becomes unnecessary, and attachment to the vehicle C, particularly retrofitting, becomes easy and the device is easy to handle.

In the present invention, since the notification sound is an amplification of the sound generated by the inverter I acquired by the contact pickup device 3, the sound generated directly from the inverter I increases as the vehicle speed increases and can be discriminated from each other. Disappear. Therefore, since the driver and passengers are not bothered, the control means 4 does not have to perform control for reducing the amplification amount by the amplifier device or stopping the amplifier output as in the above example.

  As shown in FIGS. 1 and 2, the notification sound generator 2 is attached to a body component 9 that is visible from the periphery of the vehicle (exposed to the outside), and converts the electrical signal output from the amplifier device 5 into mechanical vibration. When the vibrator 10 outputs mechanical vibration, the body constituent member 9 functions as a diaphragm, and a notification sound is emitted around the vehicle. Specifically, as shown in FIGS. 4 to 6, the vibration unit 1 in which a plurality of vibrators 10 are connected is configured, and the vibration unit 1 is attached to the body constituting member 9. However, the present invention is not limited to the above-described configuration in which the body component 9 is vibrated by the vibrator 10 to generate the notification sound, and various speakers such as a cone type speaker may be employed.

  The vibration unit 1 is, for example, the farthest from the room, and can prevent the transmission of the notification sound into the room, so that the inner surfaces of the front and rear bumpers 90 and 91 (the inner surface opposite to the outer surface (exposed surface) seen from the periphery of the vehicle) In the following description, this example will be described. However, it may be provided on other body components such as the bonnet 92, the trunk 93, the headlight cover 94, the taillight cover 95, and the inner surface of the number plate 96. Of course it is possible.

  In the vibrator 10, for example, a voice coil is mounted on the central magnetic pole of the yoke, magnets are arranged on the short side end portions on both sides of the yoke, and a diaphragm fixing portion is arranged outside each magnet on the magnet arrangement axis. A known bone conduction vibrator can be used, and the acoustoelectric signal received from the amplifier device 5 through the wiring is output as a mechanical vibration signal and transmitted to the body component 9. However, in addition to the vibrator including the magnet and the coil, a semiconductor device including a piezoelectric element that causes vibration can be used.

  As shown in FIG. 5, a plurality of vibrators 10 are connected to the vibration unit 1. In this example, the vibrators 10 are arranged and bonded in the concave grooves 11 a of the support body 11 having a U-shaped cross section. As shown in FIG. 6, the support main body 11 is engaged with the vibrator 10 in the concave groove 11a pressed against the body component 9 by the locking piece 90a projecting on the body component 9 side. It has a mounting structure that is stopped. Since the vibration unit 1 is provided with a plurality of the vibrators 10 in this way, the body component 9 itself can be sufficiently vibrated even though it has a compact structure without a cone. Volume and sound quality higher than cone-type speakers can be maintained, and since there are multiple vibrators, even if one breaks due to a broken wire, etc., the other functions can be maintained, preventing important notification sounds from suddenly failing. it can.

  The vibration unit 1 is not particularly limited to such a structure. Also, regarding the attachment structure, there may be various structures such as those using attachment screws and adhesives as long as each vibrator 10 can be in close contact with the body constituting member 9. What is necessary is just to select the optimal attachment structure according to the kind of the other body structural member 9 to attach. The number of vibrators 10 is preferably about 2 to 5 per vibration unit 1. If it is too much, vibration will be hindered. In order to further improve the waterproofness and dustproofness of the vibrator, the others may be resin-sealed in the groove 11a in a form in which the vibration surface of each vibrator 10 is exposed.

  The vibrators 10 in the concave groove 11a are connected in parallel to each other, and all receive the acoustoelectric signal from the amplifier device 5 and perform the same vibration (amplitude, frequency) operation. Thereby, even if each parallel wiring in the concave groove 11a is disconnected for some reason, the probability that all the vibrators stop functioning is reduced. In this example, the wiring connected in parallel inside extends to the outside, but the wiring of each vibrator 10 may be extended to the outside and connected in parallel outside. In addition, it is possible to supply an acoustoelectric signal from the amplifier device 5 by wiring independent from each other without externally connecting them in parallel. This vibration unit 1 is fixed to a total of four left and right corners of the front and rear bumpers 90 and 91, thereby vibrating the entire front and rear bumpers 90 and 91, and amplifying the inverter casing vibration sound around the vehicle C. A notification sound is emitted.

  Although the embodiments of the present invention have been described above, the present invention is not limited to these embodiments, and can of course be implemented in various forms without departing from the gist of the present invention.

S presence notification system C vehicle I inverter M electric motor 1 vibration unit 2 notification sound generator 3 contact pickup device 4 control means 5 amplifier device 6 control box 9 body constituent member 10 vibrator 11 support main body 11a concave groove 90, 91 bumper 90a Locking piece 92 Bonnet 93 Trunk 94 Headlight cover 95 Taillight cover 96 Number plate

Claims (5)

A presence notification system provided in a vehicle that includes an electric motor as a power source and uses an inverter in a drive circuit that drives the electric motor,
A contact pickup device that is attached to the casing of the inverter and captures the vibration of the casing of the inverter and converts it into an electrical signal;
An amplifier that amplifies the electrical signal output from the contact pickup device;
It consists of a notification sound generator that outputs sound around the vehicle based on the electrical signal output from the amplifier device,
A presence notification system comprising control means for controlling the operation of the amplifier device based on a change in frequency of an electrical signal output from the contact pickup device.   The presence notification system according to claim 1, wherein the control unit stops the output of the amplifier device when the frequency exceeds a predetermined value. The notification sound generating device is attached to a body structural member that can be seen from the periphery of a vehicle, and includes a vibrator that converts an electrical signal output from the amplifier device into mechanical vibration, and the vibrator outputs mechanical vibration. The presence notification system according to claim 1, wherein a notification sound is emitted around the vehicle using the body component member to which the vibrator is attached as a diaphragm.   The presence notification system according to claim 1, wherein the contact pickup device is a bone conduction pickup microphone.   The presence notification system according to claim 1, wherein the vehicle is a hybrid vehicle, an electric vehicle, or a fuel cell vehicle.

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