Vehicle alarm device and vehicle alarm method

1. A vehicle alarm device comprising:

a vibration generator configured to generate an alarm vibration having a frequency corresponding to a frequency of a received alarm signal;

a vibration transmission member configured to transmit the alarm vibration generated by the vibration generator to a user;

a travel situation information acquisition unit configured to acquire travel situation information which is information that causes an increase or decrease in magnitude of a travel vibration in a vehicle, wherein when a value of the travel situation information increases or decreases in accordance with a travel situation of the vehicle, the magnitude of the travel vibration increases or decreases; and

an alarm signal generator configured to generate the alarm signal such that when the value of the travel situation information acquired by the travel situation information acquisition unit is high, a signal to be inputted to the vibration generator includes at least a high-band frequency and such that when the value of the travel situation information acquired by the travel situation information acquisition unit is low, the signal to be inputted to the vibration generator includes at least a low-band frequency, wherein

the alarm signal generator generates the alarm signal by extracting a band from a frequency range in which the alarm vibration can be felt by the user,

when the value of the travel situation information acquired by the travel situation information acquisition unit is high, the alarm signal generator sets a frequency range from which the band is to be extracted, to a high frequency range, and

when the value of the travel situation information acquired by the travel situation information acquisition unit is low, the alarm signal generator sets the frequency range from which the band is to be extracted, to a low frequency range.

2. The vehicle alarm device according to claim 1 , wherein the travel situation information is one of a value of a travel speed of the vehicle, a value of engine revolutions per minute of the vehicle, and a value of a vibration sensor detected in the vehicle.

3. The vehicle alarm device according to claim 1 , wherein

when the value of the travel situation information acquired by the travel situation information acquisition unit increases, the alarm signal generator changes a value of a high band-side cutoff frequency in the frequency range from which the band is to be extracted, to a higher frequency, and

when the value of the travel situation information acquired by the travel situation information acquisition unit decreases, the alarm signal generator changes the value of the high band-side cutoff frequency to a lower frequency.

4. The vehicle alarm device according to claim 1 , wherein

when the value of the travel situation information acquired by the travel situation information acquisition unit increases, the alarm signal generator changes a value of a low band-side cutoff frequency in the frequency range from which the band is to be extracted, to a higher frequency, and

when the value of the travel situation information acquired by the travel situation information acquisition unit decreases, the alarm signal generator changes the value of the low band-side cutoff frequency to a lower frequency.

5. The vehicle alarm device according to claim 1 , wherein the alarm signal generator adjusts a level of the alarm signal so that the level does not exceed a level of a vibration that the vibration generator is capable of generating.

6. A vehicle alarm method performed by a vehicle alarm device that generates an alarm vibration having a frequency corresponding to a frequency of a received alarm signal using a vibration generator and transmits the alarm vibration to a user through a vibration transmission member, the vehicle alarm method comprising:

a travel situation information acquisition step of acquiring, by a travel situation information acquisition unit, travel situation information which is information that causes an increase or decrease in magnitude of a travel vibration in a vehicle, wherein when a value of the travel situation information increases or decreases in accordance with a travel situation of the vehicle, the magnitude of the travel vibration increases or decreases;

an alarm signal generation step of generating, by an alarm signal generator, the alarm signal such that when the value of the travel situation information acquired in the travel situation information acquisition step is high, a signal to be inputted to the vibration generator includes at least a high-band frequency and such that when the value of the travel situation information acquired in the travel situation information acquisition step is low, the signal to be inputted to the vibration generator includes at least a low-band frequency; and

an alarm vibration generation step of generating, by the vibration generator, the alarm vibration on the basis of the alarm signal generated in the alarm signal generation step, wherein

in the alarm signal generation step, the alarm signal generator generates the alarm signal by extracting a band from a frequency range in which the alarm vibration can be felt by the user, and

when the value of the travel situation information acquired in the travel situation information acquisition step is high, the alarm signal generator sets a frequency range from which the band is to be extracted, to a high frequency range, and

when the value of the travel situation information acquired in the travel situation information acquisition step is low, the alarm signal generator sets the frequency range from which the band is to be extracted, to a low frequency range.

7. The vehicle alarm method according to claim 6 , wherein the travel situation information is one of a value of a travel speed of the vehicle, a value of engine revolutions per minute of the vehicle, and a value of a vibration sensor detected in the vehicle.

8. The vehicle alarm method according to claim 6 , wherein

in the alarm signal generation step, the alarm signal generator changes a value of a high band-side cutoff frequency in the frequency range from which the band is to be extracted, to a higher frequency when the value of the travel situation information acquired in the travel situation information acquisition step increases and changes the value of the high band-side cutoff frequency to a lower frequency when the value of the travel situation information acquired in the travel situation information acquisition step decreases.

9. The vehicle alarm method according to claim 6 , wherein

in the alarm signal generation step, the alarm signal generator changes a value of a low band-side cutoff frequency in the frequency range from which the band is to be extracted, to a higher frequency when the value of the travel situation information acquired in the travel situation information acquisition step increases and changes the value of the low band-side cutoff frequency to a lower frequency when the value of the travel situation information acquired in the travel situation information acquisition step decreases.

10. The vehicle alarm method according to claim 6 , wherein in the alarm signal generation step, the alarm signal generator adjusts a level of the alarm signal so that the level does not exceed a level of a vibration that the vibration generator is capable of generating.