JP2000001142A - Engine mock sound generator for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the engine mock sound generator generating engine mock sounds with a touch of actual engine, which is manufactured at a low cost. SOLUTION: This engine mock sound generator comprises an engine speed detection means 4 to detect the engine speed of an engine 2 and an accelerator operation amount detection means 6 to detect accelerator operation amount. It also has a map 13 which is created by allocating the sound pressure pulsated data of the engine sound within a predetermined time to the engine speed and the accelerator operation amount. A sound pressure pulsated data corresponding to the accelerator operation amount is read from said map 13. The generator comprises an engine mock sound generating means 7 which generates engine mock sounds using this sound pressure pulsated data.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a simulated engine sound generator for a vehicle which generates simulated engine sounds when mounted on a vehicle such as an automobile, a motorcycle and an electric vehicle.

[0002]

2. Description of the Related Art In recent years, noise generated when an automobile or a motorcycle travels has been significantly reduced. This noise includes engine noise, road noise generated when the tire rotates, and wind noise (fluid noise) generated by running wind hitting the vehicle body. Of these sounds, the engine noise has been reduced the most, and the engine sound that can be heard inside a car or the driver of a motorcycle wearing a helmet has become significantly less than ten years ago. I have.

[0003] Since the volume and sound quality of the engine sound change according to the operation of the accelerator, the engine sound is one of the pleasures of driving for some drivers.
However, when the engine sound is reduced as described above, it is not possible to meet the driver's request to enjoy the engine sound.

In order to meet such a demand without illegally modifying a vehicle, a speaker is provided near an exhaust port of a muffler, and a loud engine sound is provided in a vehicle or a helmet. It is conceivable that this occurs. However, since exhaust gas or muddy water is likely to be applied to the vicinity of the exhaust port, the micro fins to be mounted here must be excellent in weather resistance and heat resistance, resulting in an increase in cost. Moreover, the exhaust sound generated by the exhaust sound amplifying device is less powerful than the exhaust sound generated by a muffler that has been tampered with so as to increase the exhaust sound. In order to solve such a problem, it is conceivable that a sound imitating an engine sound (hereinafter, simply referred to as an engine simulation sound) is generated by the speaker.

As a device for generating this kind of engine simulation sound, there is a device provided in a game machine, a driving simulator, or the like. Conventional engine simulation sound generator
The sound of the engine sound of the vehicle during steady driving is recorded for only a few seconds, and the sound data stored in advance as a digital signal is converted into a pitch / frequency (pitch) according to the operating state of the engine (rotational speed and accelerator operation amount). It adopts a configuration that repeats playback while changing ｛and volume ｛sound pressure (sound volume)｝. In this engine simulation sound generating device, the pitch increases in proportion to the engine rotational speed when the engine rotational speed increases, and decreases when the engine rotational speed decreases. The volume increases when the accelerator is depressed, and decreases when the accelerator is returned.

[0006]

The engine simulated sound generator constructed as described above is used when the actual engine speed or the accelerator operation amount is close to the engine speed at the time of recording the engine sound or the accelerator operation amount, that is, when the engine operation speed is constant. In the driving state, the engine simulation sound is close to the actual engine sound, and the reality is high. However, the engine speed,
When the accelerator operation amount is significantly different from that at the time of recording the engine sound, or when the engine rotation speed and the accelerator operation amount are in a transient state, there is a problem that the engine simulation sound becomes unnatural. Further, when the vehicle is driven at a constant speed, that is, when there is no change in the engine rotation speed or the throttle operation amount, the same sound is continuously reproduced, so that the engine simulation sound becomes monotonous.

[0007] Such a problem can be solved by recording the engine sound in all operating states and storing it in a storage device. However, in order to realize this, the capacity of the storage device becomes extremely large, and the cost becomes extremely high.

On the other hand, electric vehicles such as electric vehicles and electric motorcycles that run using a motor as a power source generate less noise when stopped and when running than engine-type vehicles. Operation information such as rotation speed must be checked with a meter or the like. Further, in the electric vehicle, there is a problem that the sound heard by the pedestrian is small in addition to the sound heard by the driver.
That is, it is necessary to make nearby pedestrians aware of the vehicle.

SUMMARY OF THE INVENTION The present invention has been made in order to solve such a problem, and a first object of the present invention is to provide an engine simulation sound generating device which produces a realistic engine simulation sound at a low manufacturing cost. And It is a second object of the present invention to make the engine simulation sound audible to a driver or a pedestrian even in an electric vehicle.

[0010]

A vehicle engine simulation sound generating apparatus according to the present invention comprises: a rotational speed detecting means for detecting a rotational speed of a power unit; an accelerator operation amount detecting means for detecting an accelerator operation amount; A map formed by assigning the sound pressure waveform data within a predetermined time of the sound to the rotation speed and the accelerator operation amount, and the sound pressure waveform data corresponding to the accelerator operation amount and the rotation speed are read from the map, and the sound pressure Engine simulation sound generating means for generating an engine simulation sound using the waveform data.
According to the present invention, an engine simulation sound corresponding to the rotation speed of the power unit and the operation amount of the accelerator is generated. The power unit is a motor unit for an engine or an electric vehicle.

According to another aspect of the present invention, there is provided a vehicle engine simulated sound generating apparatus according to the above-described invention, wherein the engine simulated sound generating means includes a sound pressure, a frequency, and a timbre included in sound pressure waveform data. Sound generation control means for changing at least one of the sound data composed of According to the present invention, the engine simulation sound constantly changes even when the vehicle is driven at a constant speed, and sounds like the engine sound of an engine having a variation in explosion.

A vehicle engine simulated sound generating device according to another invention is the vehicle engine simulated sound generating device according to the above-described invention, wherein a map is formed by arranging a large number of unit regions in which the rotation speed and the accelerator operation amount have a constant width. In addition, the sound pressure waveform data for one combustion cycle of the engine when the engine operation state is substantially at the center of the rotation speed width and the accelerator operation width in the unit region is formed and formed in each of the unit regions, A reproduction rate that changes the frequency of the engine simulation sound so that there is no speed difference between the engine rotation speed when the engine sound that is the basis of the sound pressure waveform data is recorded in the engine simulation sound generation means and the rotation speed of the power unit. A changing means is provided.

According to the present invention, when the operating state of the power unit is within the unit area in both the rotational speed and the accelerator operation amount, an engine simulation sound is generated using one sound pressure waveform data in any operating state. I do. For this reason, compared to the case where the engine sound is recorded in all operating states and stored in the storage device, the engine simulation sound is generated over the entire operating range of the power unit even if the number of sound pressure waveform data is small. Therefore, the capacity of the storage device can be relatively reduced.

When the rotation speed of the power unit changes and the unit area of the map corresponding to the rotation speed changes, the reproduction time of the engine simulation sound corresponding to one sound pressure waveform data depends on the rotation speed of the power unit. Therefore, the engine simulation sound gradually changes from the sound corresponding to the sound pressure waveform data in one unit area to the sound corresponding to the sound pressure waveform data in the other unit area.

According to another aspect of the present invention, there is provided a vehicle engine simulated sound generating device according to any one of the above-described vehicle engine simulated sound generating devices, wherein the power unit is a motor drive unit for an electric vehicle. The engine simulation sound generating means is configured to transmit the engine simulation sound outside the vehicle. According to the present invention, the simulated engine sound emitted by the electric vehicle can be heard by a nearby pedestrian.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First Embodiment Hereinafter, an embodiment of a vehicle engine simulation sound generating apparatus according to the present invention will be described in detail with reference to FIGS.

FIG. 1 is a block diagram of an automobile equipped with an engine simulation sound generating device according to the present invention, FIG. 2 is a block diagram showing the configuration of a vehicle engine simulation sound generating device according to the present invention, and FIG. FIG. 4 is a diagram showing a configuration of a map, and FIG. 5 is a graph showing a change in an operation state at the time of sudden acceleration / deceleration. FIG. 6 is a graph showing a change in the unit area read by the engine simulation sound output means at the time of rapid acceleration / deceleration and at the time of slow acceleration / deceleration. FIGS. 7A and 7B are graphs showing the sound pressure waveform of the engine simulation sound for explaining the operation of the reproduction rate changing means. FIG. 7A shows a case where the reproduction rate is not changed, and FIG. Shows the case when changed. FIG. 8 is a graph showing a sound pressure waveform of an actual engine sound, and FIG. 9 is a graph showing a spectrum of an actual engine sound.

In these figures, what is indicated by reference numeral 1 is an automobile according to this embodiment. This car 1
The vehicle runs with the electronically controlled four-cycle engine 2 as a power source.
Is installed in the cabin.

As shown in FIG. 2, the engine simulation sound generating device 3 includes an engine rotational speed detecting means 4 for detecting a rotational speed of the engine 2 and an accelerator operation amount detecting means 6 for detecting an operation amount of an accelerator pedal 5. And an engine simulation sound generating means 7 for generating an engine simulation sound based on the engine rotation speed and the accelerator operation amount, and a volume adjustment means 8 for artificially adjusting the volume of the engine simulation sound.
Is provided.

The engine rotational speed detecting means 4 is connected to an engine rotational speed detecting sensor 9 for detecting the rotation of a cam shaft of the engine 2, for example, and is configured to always detect the rotational speed of the engine 2 during engine operation. I have.

The accelerator operation amount detecting means 6 includes an accelerator operation amount detecting sensor 10 connected to the accelerator pedal 5.
To detect the amount of depression of the accelerator pedal 5. The sensor 9 for detecting the engine rotational speed and the sensor 10 for detecting the accelerator operation amount are provided for controlling the electronically controlled engine 2. That is, these sensors 9 and 10 are used for both control of the engine 2 and generation of the engine simulation sound.
Further, as shown in FIG. 1, the sound volume adjusting means 8 is mounted on an operation panel 11 at the front of the vehicle compartment, so that the driver can operate while driving.

The engine simulation sound generating means 3 receives the engine rotational speed signal output from the engine rotational speed detecting means 4 and the accelerator operation amount signal output from the accelerator operation amount detecting means 6 and generates a sound generation control signal. Sounding control means 12, a storage means 14 having a map 13 for storing sound pressure waveform data of actual engine sounds, a sounding control signal generated by the sounding control means 12 and the map 13
A simulation sound output means 15 for generating a sound pressure signal of an engine simulation sound based on the sound pressure waveform data read from the CPU, an amplifier 16 for amplifying the sound pressure signal, and a speaker 17 connected to the amplifier 16 are doing.

The sound control means 12 and the simulated sound output means 15 are implemented as software in a circuit of a microcomputer (not shown), and the storage means 14 is constituted by a semiconductor memory connected to the microcomputer. I have. The amplifier 16 and the speaker 1
Reference numeral 7 denotes a device equipped for car audio in this embodiment, and is used for both generation of music and the like and generation of engine simulation sound. Amplifier 16
1 is arranged at the front of the vehicle compartment as shown in FIG. 1, and the speakers 17 are arranged at the front and rear portions of the vehicle interior so that sound propagates into the vehicle interior. In the four-stroke cycle engine, the sound generation control means 12 is configured to transmit a sound generation control signal to the simulated sound output means 15 for a certain time every two rotations of the crankshaft (one combustion cycle of the engine). The time for transmitting the sound control signal is the time required for the crankshaft to make two revolutions. That is, during the operation of the engine, the sound emission control signal is sent from the sound emission control means 12 to the simulated sound output means 15 every cycle for one combustion cycle determined according to the rotation speed at that time.

As shown in FIG. 3, the tone generation control signal is
Simulating sound output means 15 for pitch (frequency) of engine simulating sound
, A signal for setting the magnitude (sound pressure) of the engine simulation sound by the simulation sound output means 15, and a timbre signal for setting the timbre (waveform) by the simulation sound output means 15. And a signal (not shown) indicating the accelerator pedal operation amount and the engine rotation speed. The setting of the timbre is performed by passing the engine simulation sound through a cut filter (not shown) to delete an unnecessary sound range. For this reason, the timbre signal is generated so that the frequency (filter cut frequency) to be deleted by the filter can be determined.

Further, in this embodiment, the tone generation control means 12 adopts a configuration in which the above three kinds of signals are slightly changed each time the signals are transmitted to the simulation sound output means 15. That is, the pitch, loudness, and timbre of the engine simulation sound are changed for each combustion cycle of the engine 1 (for each sound generation).

The storage means 14 selects a sound pressure waveform data corresponding to a read signal transmitted by the simulation sound output means 15 described later from the map 13 and returns the data to the simulation sound output means 15. The map 13 is formed by assigning the sound pressure waveform data of the engine sound to the engine rotation speed and the accelerator operation amount. In this embodiment, as shown in FIG. 4, a large number of unit areas (1 to 24) each having a fixed width are provided in parallel with the engine rotation speed and the accelerator operation amount, and the sound pressure waveform data is stored in all the unit areas. Are stored one by one to form the map 13. In the map 13, the unit region 1 corresponds when the engine 1 is in the idling operation state, and the unit region 24 corresponds when the engine 1 is at the maximum output.

The sound pressure waveform data is recorded as digital data by recording an engine sound for one combustion cycle of the engine 2 when the operating state of the engine 2 is substantially at the center of the rotation speed width and the accelerator operation width in each unit area. It is converted.

The simulation sound output means 15 reads out a unit area of the map 13 based on the engine speed data and the accelerator operation amount data included in the sound emission control signal transmitted by the sound emission control means 12. The signal is sent to the storage means 14 and changes every two crankshaft revolutions using the sound pressure waveform data read from the storage means 14 and the three types of sound data included in the sounding control signal. A sound pressure signal is generated and sent to the amplifier 16. When the sound pressure signal is sent to the amplifier 16, the sound pressure signal is amplified by the amplifier 16 and a simulated engine sound is generated from the speaker 17. The simulation sound output means 15 is configured so that the sound volume adjustment means 8 is connected thereto, and the sound volume of the engine simulation sound can be increased or decreased by operating the sound volume adjustment means 8.

The sound pressure waveform data read out from the storage means 14 by the simulation sound output means 15 is selected from those corresponding to the engine speed and the accelerator operation amount at that time. The selection of the sound pressure waveform data is performed, for example, when the operating state changes as shown in FIG. 5, that is, when the accelerator pedal 5 is suddenly largely depressed and sudden acceleration is performed without operating the transmission, and then a certain amount of operation is performed. When performing rapid acceleration / deceleration such as keeping the accelerator pedal 5 off suddenly,
This is performed as follows.

At the time of rapid acceleration, the engine rotation speed starts to increase after the accelerator operation is performed due to the inertia of the rotating member of the engine 2 and the vehicle body. At this time, the loudness of the intake sound and the exhaust sound of the engine 2 changes according to the accelerator operation amount, and the loudness of the mechanical sound of the engine 2 does not change much depending on the accelerator operation amount. It changes greatly according to the rotation speed of the engine 2. For this reason, at the time of rapid acceleration, first, the intake sound and the exhaust sound are relatively large,
Thereafter, the mechanical noise increases as the engine rotation speed increases.

At the time of such rapid acceleration, an arrow A in FIG.
As shown by, from the unit area 1 of the map to the unit area 7 → 1
The unit areas are selected in the order of 3 → 19 → 20 → 21 → 22 → 23 → 24, and the respective sound pressure waveform data are read.

At the time of rapid deceleration, first, the intake sound and the exhaust sound become smaller, and the mechanical sound of the engine 2 becomes smaller as the engine speed decreases. For this reason, at the time of sudden deceleration, as shown by the arrow B in FIG.
The unit areas are selected in the order of → 12 → 6 → 5 → 4 → 3 → 2 → 1 and the respective sound pressure waveform data are read out.
In addition, when performing the idling operation, the response of the engine 2 becomes faster than during the rapid acceleration / deceleration because there is no inertia of the vehicle body.

On the other hand, when the acceleration and deceleration are performed gently, the force required to accelerate the rotating member of the engine 2 and the vehicle body is negligibly small compared to the running resistance. The rotation speed increases / decreases. For this reason, at the time of this slow acceleration / deceleration, arrows C,
As shown by D, a unit area is selected along the diagonal line of the map 13 between the unit area 1 and the unit area 24, and each sound pressure waveform data is read.

As described above, if the engine pressure sound is generated by sequentially reading out the sound pressure waveform data, when the accelerator operation amount is constant, even if the engine rotation speed changes within the unit area, the generated engine simulation sound is substantially equal. Be the same. For this reason, when the engine rotation speed changes over a plurality of unit areas, the engine simulation sound changes stepwise.

In order to prevent such a phenomenon from occurring, the simulation sound output means 15 changes the reproduction rate (sound generation time) of the engine simulation sound in accordance with the rotation speed of the engine 2. It has.

The reproduction rate changing means 18 eliminates the difference between the engine speed at the time of recording the engine sound which is the basis of the sound pressure waveform data and the engine speed detected by the engine speed detecting means 4. The frequency of the engine simulation sound and the sounding time are changed. Here, the operation of the reproduction rate changing means 18 will be described with reference to FIG. 7, including a more detailed description of the configuration of the reproduction rate changing means 18.

Here, it is assumed that the sound pressure waveform data of the unit area 1 is generated by recording the engine sound at the engine speed of 2400 rpm, and the sound pressure waveform data of the unit area 2 is generated at the engine speed of 3600 rpm. The case of recording and generation will be described. In this case, the time required for the crankshaft to make two rotations is 50 msec in the unit area 1 and about 33 msec in the unit area 2. For this reason, unless the reproduction rate of the engine simulation sound is changed, as shown in FIG. 7A, the length of the engine simulation sound is different between the unit area 1 and the unit area 2, so that sound does not occur at the boundary between the unit areas. It changes naturally. In FIG. 7A, the lengths of the sound for two rotations of the crankshaft are indicated by reference numerals t1 and t2.

Assuming that the engine speed at the boundary between the unit area 1 and the unit area 2 is 3000 rpm, the length of the sound at this boundary speed is 3000 / the length of the engine simulation sound in the unit area 1. Since 2400 = 1.25, the reproduction rate changing means 18 increases the reproduction rate by 25% so that the sound length t1 for two revolutions of the crankshaft becomes 40 msec. The length of the sound at the boundary rotation speed is 3000/36 with respect to the length of the engine simulation sound in the unit area 2.
Since 00 = 0.83, the reproduction rate changing means 18 reduces the reproduction rate by 17% and extends the sound length t2 for two revolutions of the crankshaft to 40 msec.

As described above, by changing the reproduction rate of the engine simulation sound by the reproduction rate changing means 18, the engine simulation sound can be reproduced so as to have the same length in the transition region including the boundary between the unit areas. A natural engine simulation sound can be generated.

Therefore, the engine simulation sound generating apparatus 3 according to this embodiment assigns the sound pressure waveform data for two rotations of the crankshaft of the engine sound to the map 13 for the engine speed and the accelerator operation amount, and stores the map. 1
Since an engine simulation sound is generated by using the sound pressure waveform data read from the engine 3, the engine simulation sound is generated corresponding to the engine speed and the accelerator operation amount. Therefore, the driver of the car can hear the natural engine simulation sound.

Since the engine simulation sound is generated by changing the sound pressure, frequency, and sound data of the sound pressure waveform data, the engine simulation sound constantly changes even when the vehicle is driven at a constant speed. Then, the sound is similar to the engine sound of the engine 2 in which the explosion varies. The actual engine sound varies as shown in FIG. 8 because the explosion is not constant every time. Because of such variations, the engine sound is not monotonous in an actual engine. The spectrum of the engine sound shown in FIG. 8 appears as shown in FIG. As can be seen from FIG. 9, the actual engine sound is generated by mixing sounds distributed over a wide frequency range.

Further, the engine simulation sound generating device 3
The map 13 is formed by storing the sound pressure waveform data for one combustion cycle of the engine at approximately the center of a unit region where the engine rotation speed and the accelerator operation amount have a constant width, and forms the actual engine rotation speed and sound pressure waveform. Since the reproduction rate of the engine simulation sound is changed so as to eliminate the speed difference from the rotation speed at the time of data storage, what is the case when the operation state of the engine 2 is within the unit area for both the engine rotation speed and the accelerator operation amount? An engine simulation sound is generated by using one sound pressure waveform data even in a normal driving state. For this reason, compared to the case where the engine sound is recorded in all operating states and stored in the storage means, the engine simulation sound is generated over the entire operating range of the engine 2 even if the number of sound pressure waveform data is small. Therefore, the capacity of the storage means can be relatively reduced. In addition, when the rotation speed of the engine 2 changes and the unit area of the map 13 corresponding to the rotation speed changes, the reproduction time of the engine simulation sound corresponding to one sound pressure waveform data depends on the rotation speed of the engine 2. Therefore, the engine simulation sound gradually changes from the sound corresponding to the sound pressure waveform data in one unit area to the sound corresponding to the sound pressure waveform data in the other unit area. Therefore, the engine simulation sound naturally changes.

In addition, the engine simulation sound generating device 3 according to this embodiment uses the sensors 9 and 10 for detecting the engine rotation speed and the accelerator operation amount as the sensors of the engine control system, and connects the amplifier 16 and the speaker 17 to the audio. Since the engine simulated sound generating device 3 is provided, it is possible to minimize an increase in cost due to the provision of the engine simulation sound generating device 3.

Second Embodiment The engine simulation sound generating apparatus according to the present invention can be applied to a motorcycle as shown in FIG.

FIG. 10 is a block diagram showing another embodiment in which the present invention is applied to a motorcycle. In this figure, the same or equivalent members as those described in FIGS. 1 to 9 are denoted by the same reference numerals, and detailed description is omitted.

In FIG. 10, what is indicated by reference numeral 21 is
This is a motorcycle according to this embodiment. The engine simulation sound generating device 3 mounted on the motorcycle 21 is disposed below a seat (not shown) on which a driver sits, excluding the amplifier 16 and the speaker 17, and the amplifier 16 and the speaker 17 are mounted on the helmet 22. It is arranged. Further, a sound pressure signal is sent from the simulation sound output means 15 (not shown) of the engine simulation sound generation device 3 to the amplifier 16 to the infrared communication device 23.
Is sent by the

The infrared communication device 23 is provided with an infrared transmitter 2 disposed in front of the vehicle body, for example, above a fuel tank.
3a and an infrared receiver 23b provided on the jaw of the helmet 22.

The engine speed sensor 9 for detecting the engine speed detects the rotation of the crankshaft, and the accelerator operation amount sensor 10 detects the throttle valve opening of the carburetor. Has been adopted.

Thus, by equipping the motorcycle 21 with the engine simulation sound generating device 3 according to the present invention, the engine simulation sound can be heard while the motorcycle 21 is operating. Further, since the helmet side and the vehicle body side are connected by the infrared communication device 23, the driver is not restrained by the vehicle body when getting on or off the vehicle or driving.

Third Embodiment The engine simulation sound generating apparatus according to the present invention can be applied to an electric vehicle as shown in FIGS.

FIG. 11 is a block diagram of an electric vehicle equipped with an engine simulation sound generating device according to the present invention, and FIG. 12 is a block diagram showing an engine simulation sound generating device for an electric vehicle. In these drawings, the same or equivalent members as those described in FIGS. 1 to 9 are denoted by the same reference numerals, and detailed description is omitted.

In FIG. 11, what is indicated by reference numeral 31 is an electric vehicle according to this embodiment. The electric vehicle 31 has a structure in which a motor drive unit 32 is mounted on a front portion of a vehicle body and travels by the power of a motor.

The engine simulation sound generating device 3 mounted on the electric vehicle 31 has a structure in which the rotation speed of the motor is detected instead of the engine rotation speed, and a structure in which the engine simulation sound is propagated outside the vehicle body. Other than the above, the configuration is the same as that of the first embodiment.

In order to detect the rotation speed of the motor, the rotation of the wheels 33 is detected by a vehicle speed sensor 34, and FIG.
A configuration is adopted in which the rotation speed of the motor is obtained from the vehicle speed by the traveling speed detection means indicated by reference numeral 35 therein. The traveling speed detection means 35 sends a motor rotation speed signal to the sound generation control means 12.

The speakers 17 are also provided at the front and rearmost portions of the vehicle body. The speaker 17 at the forefront of the vehicle generates an engine simulation sound toward the front of the vehicle, and the speaker 17 at the rear of the vehicle generates an engine simulation sound toward the rear of the vehicle.

By equipping the electric vehicle 31 with the engine simulation sound generating device 3 according to the present invention, the electric vehicle 31 emits engine simulation sound.
This engine simulation sound will be heard by nearby pedestrians. Therefore, the presence of the electric vehicle 31 can be notified to the pedestrian by the engine simulation sound.

In any of the above-described three embodiments, the actual engine speed and motor speed detected by the engine simulation sound generator 3 can be multiplied by a constant. By adopting this configuration, it is possible to generate an engine simulation sound as if the engine is running at a high speed even when the actual engine speed (motor speed) is low, and the actual engine speed (motor speed).
It is possible to generate an engine simulation sound as if driving at a lower rotation speed.

Further, the map 13 of the storage means 14 may be configured to be able to be changed artificially. For example, the storage means 1 is used so that a plurality of maps 13 can be exchanged and used.
4 and storing sound pressure waveform data of a different engine sound in each map 13, an engine sound of a vehicle type different from that of the own vehicle can be generated as an engine simulation sound.

[0059]

As described above, according to the present invention, an engine simulation sound corresponding to the rotation speed of the power unit and the operation amount of the accelerator is generated, so that a highly realistic engine simulation sound according to the running state is generated. Can be generated.

Therefore, by mounting this engine simulation sound generator on an engine-type vehicle or an electric vehicle, the driver can hear a natural engine simulation sound. In particular, by mounting the engine simulation sound generating device on an electric vehicle, the driver can know the driving information of the own vehicle such as the motor rotation speed by hearing without relying on the meter.

According to another aspect of the invention, the sound pressure control means for changing at least one of the sound pressure, frequency, and sound data included in the sound pressure waveform data is provided. However, the engine simulation sound changes constantly, and it sounds like the engine sound of an engine that varies in explosion. Therefore, a natural engine simulation sound closer to the actual engine can be generated.

A map is formed by storing sound pressure waveform data for one combustion cycle of the engine at substantially the center of a unit region where the rotation speed and the accelerator operation amount have a constant width, and stores the actual rotation speed and sound pressure waveform data. According to another invention in which the frequency of the engine simulation sound is changed so that the speed difference with the rotation speed at the time disappears, when the operating state of the power unit is within the unit region, both the rotation speed and the accelerator operation amount are within the unit area. An engine simulation sound is generated using one sound pressure waveform data even in the operating state.

For this reason, compared with the case where the engine sound is recorded in all the operating states and stored in the storage device,
Even if the number of sound pressure waveform data is small, the engine simulation sound can be generated over the entire operating range of the power unit, so that the capacity of the storage device can be relatively reduced.

When the rotation speed of the power unit changes and the unit area of the map corresponding to the rotation speed changes, the reproduction time of the engine simulation sound corresponding to one sound pressure waveform data depends on the rotation speed of the power unit. Therefore, the engine simulation sound gradually changes from the sound corresponding to the sound pressure waveform data in one unit area to the sound corresponding to the sound pressure waveform data in the other unit area.

Therefore, the vehicle engine simulation sound generating apparatus according to the present invention is inexpensive because the storage device has a small capacity, and can naturally generate the engine simulation sound even when the operating range of the power unit is in the transient range. Can be changed.

According to a vehicle engine simulated sound generating apparatus according to another invention in which the power unit is a motor drive unit for an electric vehicle and an engine simulated sound is propagated outside the vehicle, an engine simulated sound generated by the electric vehicle is provided. Since the sound can be heard by a nearby pedestrian, the presence of the electric vehicle can be notified to the pedestrian by the engine simulation sound.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an automobile equipped with an engine simulation sound generating device according to the present invention.

FIG. 2 is a block diagram showing a configuration of a vehicle engine simulation sound generating device according to the present invention.

FIG. 3 is a graph showing an example of a sound control signal.

FIG. 4 is a diagram showing a configuration of a map.

FIG. 5 is a graph showing a change in an operation state during sudden acceleration / deceleration.

FIG. 6 is a graph showing a change in a unit area read by the engine simulation sound output means during rapid acceleration / deceleration and during slow acceleration / deceleration.

FIG. 7 is a graph showing a sound pressure waveform of an engine simulation sound for explaining the operation of the reproduction rate changing means.

FIG. 8 is a graph showing a sound pressure waveform of an actual engine sound.

FIG. 9 is a graph showing a spectrum of an actual engine sound.

FIG. 10 is a configuration diagram showing another embodiment in which the present invention is applied to a motorcycle.

FIG. 11 is a configuration diagram of an electric vehicle equipped with the engine simulation sound generating device according to the present invention.

FIG. 12 is a block diagram showing an engine simulation sound generating device for an electric vehicle.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Car, 2 ... Engine, 3 ... Engine simulation sound generation device, 4 ... Engine rotation speed detection means, 6 ... Accelerator operation amount detection means, 7 ... Engine simulation sound generation means, 12 ... Sound generation control means, 13 ... Map, 14: storage means, 15: simulated sound output means, 16: amplifier, 17: speaker, 18: reproduction rate changing means, 21: motorcycle, 31: electric vehicle.

Claims (4)

[Claims] 1. A rotational speed detecting means for detecting a rotational speed of a power unit, an accelerator operation amount detecting means for detecting an accelerator operation amount, and a sound pressure waveform data of an engine sound within a predetermined period of time. A map formed by allocating to the accelerator operation amount and sound pressure waveform data corresponding to the accelerator operation amount detected by the accelerator operation amount detection means and the rotation speed detected by the rotation speed detection means are read out from the map. An engine simulation sound generating device for a vehicle, comprising: engine simulation sound generation means for generating an engine simulation sound using waveform data. 2. The vehicle engine simulation sound generating apparatus according to claim 1, wherein the engine simulation sound generation means includes at least one of sound data having sound pressure, frequency, and timbre of the sound pressure waveform data. A vehicle engine simulated sound generating device provided with a sound control means for changing. 3. The vehicle engine simulation sound generating apparatus according to claim 1, wherein the map includes a plurality of unit areas having a constant width in each of a rotation speed and an accelerator operation amount, and the map includes a plurality of unit areas. Each of the unit regions is formed by storing sound pressure waveform data for one combustion cycle of the engine when the engine operation state is substantially at the center of the rotation speed width and the accelerator operation width in this unit region. Means are provided with reproduction rate changing means for changing the frequency of the engine simulation sound so that the difference between the engine speed at the time of recording the engine sound as the basis of the sound pressure waveform data and the speed of the power unit is eliminated. A vehicle engine simulated sound generator characterized in that: 4. A vehicle engine simulation sound generating apparatus according to claim 1, wherein the power unit is a motor drive unit for an electric vehicle, and the engine simulation sound generating means is an engine simulation sound. A vehicle engine simulated sound generator, wherein the sound is transmitted outside the vehicle.