Additional sound generator

Abstract

To provide an additional sound generating device that can suppress discomfort to occupants.SOLUTION: An additional sound generating device 10 generates an additive sound based on control parameters that change in response to vehicle operation, and comprises a control unit 14 that changes the additive sound slowly or delays the additive sound with respect to changes in control parameters.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to an additional sound generating device. [Background technology]

[0002] 2. Description of the Related Art Conventionally, an engine sound control device has been disclosed that uses an acceleration operation of a vehicle or the like as a control parameter and generates an acceleration sound based on the control parameter (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2007-126984 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the engine sound control device of Patent Document 1, when the control parameters suddenly change, the engine sound is added in accordance with the change in the control parameters, so that the engine sound does not match the actual vehicle state, causing an uncomfortable feeling to the occupants.

[0005] Therefore, the present disclosure provides an additional sound generating device that can suppress the discomfort felt by occupants. [Means for solving the problem]

[0006] An additional sound generating device according to one aspect of the present disclosure is an additional sound generating device that generates an additional sound based on a control parameter that changes in response to a vehicle operation, and includes a control unit that changes the additional sound slowly or changes the additional sound with a delay in response to the change in the control parameter. Effect of the Invention

[0007] The additional sound generating device of the present disclosure can suppress the discomfort felt by the occupants. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a block diagram showing a functional configuration of the additional sound generating device according to the first embodiment. [Diagram 2] FIG. 2 is a graph showing an example of control parameters before and after the slow processing. [Diagram 3] FIG. 3 is a graph showing another example of the control parameters before and after the slow processing. [Figure 4] FIG. 4 is a graph showing yet another example of the control parameters before and after the slow processing. [Diagram 5] FIG. 5 is a graph showing an example of the control parameters before and after the delay process. [Figure 6] FIG. 6 is a graph showing another example of the control parameters before and after the delay process. [Figure 7] FIG. 7 is a graph showing yet another example of the control parameters before and after the delay process. [Figure 8] FIG. 8 is a block diagram showing a functional configuration of the additional sound generating device according to the second embodiment. [Figure 9] FIG. 9 is a graph showing an example of the relationship between the accelerator opening and the volume of the additional sound. [Figure 10] FIG. 10 is a block diagram showing a functional configuration of the additional sound generating device according to the third embodiment. [Figure 11] FIG. 11 is a block diagram showing a functional configuration of the additional sound generating device according to the fourth embodiment. As shown in FIG. [Figure 12] FIG. 12 is a block diagram showing a functional configuration of the additional sound generating device according to the fifth embodiment. As shown in FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, the embodiment will be specifically described with reference to the drawings.

[0010] The embodiments described below are all comprehensive or specific examples. The numerical values, shapes, materials, components, the arrangement and connection of the components, steps, and the order of steps shown in the following embodiments are merely examples and are not intended to limit the present disclosure. Furthermore, among the components in the following embodiments, components that are not described in the independent claims showing the highest concept are described as optional components.

[0011] In addition, each drawing is a schematic diagram and is not necessarily a precise illustration. In addition, in each drawing, the same components are denoted by the same reference numerals.

[0012] (Embodiment 1) FIG. 1 is a block diagram showing a functional configuration of an additional sound generating device 10 according to the first embodiment.

[0013] As shown in FIG. 1, the additional sound generating device 10 is a device that generates additional sounds based on control parameters that change according to the operation of the vehicle. For example, the vehicle is a vehicle that runs by driving the wheels, such as an automobile or a train. Specifically, the vehicle is, for example, an electric vehicle powered by a motor, a hybrid vehicle equipped with two or more power sources, or an automobile powered by an engine. For example, the control parameters include the accelerator opening of the vehicle, the forward and backward acceleration of the vehicle, the vehicle speed, and the driving torque of the vehicle. For example, the additional sound is an engine sound or a motor sound.

[0014] The additional sound generating device 10 includes an interface (I / F) 12, a control unit 14, a signal generating unit 16, a voltage conversion unit 18, an AMP 20, and a speaker 22, and generates the additional sound from the speaker 22.

[0015] The interface 12 is communicatively connected to a sensor (not shown) for detecting a control parameter, and the detected control parameter is input to the additional sound generating device 10 from the interface 12 .

[0016] The control unit 14 changes the additional sound slowly or changes the additional sound with a delay in response to the change in the control parameter. For example, changing the additional sound slowly in response to the change in the control parameter means changing the additional sound more slowly than the change in the control parameter. Also, changing the additional sound with a delay in response to the change in the control parameter means changing the additional sound at a timing later than the timing at which the control parameter changes when the control parameter changes. That is, for example, the generated additional sound changes more slowly than the change in the control parameter or changes at a timing later than the timing at which the control parameter changes. Specifically, for example, the control unit 14 changes the volume of the additional sound slowly or changes the volume of the additional sound with a delay in response to the change in the control parameter. Note that the control unit 14 may change the sound pressure and / or pitch of the additional sound in response to the change in the control parameter.

[0017] In this embodiment, the control unit 14 performs slow processing or delay processing on the control parameters received from the interface 12, generates slow-processed or delayed control parameters, and transmits the generated slow-processed or delayed control parameters to the signal generating unit 16. For example, the control unit 14 generates a moving average of the control parameters received from the interface 12 as the delayed control parameters. Also, for example, the control unit 14 generates a slow-processed control parameter that changes with a second-order delay with respect to the change in the control parameters received from the interface 12. In this way, by performing slow processing or delay processing on the control parameters in the control unit 14, it is not necessary to provide a calculation unit for slow processing or delay processing in the signal generating unit 16, and an increase in costs can be suppressed.

[0018] Although the details will be described later, as a specific mode of slowly changing the additional sound in response to a change in the control parameter, for example, when the rate of change of the control parameter is greater than a predetermined rate, the control unit 14 changes the additional sound at a rate smaller than the rate of change of the control parameter. Also, for example, when the rate of change of the control parameter is greater than a predetermined rate, the control unit 14 changes the additional sound at the same rate as the predetermined rate. Also, for example, the control unit 14 changes the additional sound at a first rate, and then changes the additional sound at a second rate smaller than the first rate. The predetermined rate is a rate that is set in advance.

[0019] The signal generating unit 16 generates an additional sound signal based on the control parameters after the slow processing or delay processing generated by the control unit 14, and transmits the generated additional sound signal to the voltage converting unit 18. For example, the additional sound signal is a signal that changes the volume of the additional sound output from the speaker 22 in accordance with the change in the control parameters after the slow processing or delay processing. In other words, for example, the additional sound signal is a signal that changes the volume of the additional sound output from the speaker 22 at the same rate of change as the control parameters after the slow processing. Also, for example, the additional sound signal is a signal that changes the volume of the additional sound output from the speaker 22 at the same timing as the control parameters after the delay processing.

[0020] The voltage conversion unit 18 converts the additional sound signal generated by the signal generation unit 16 into a voltage for driving the speaker 22 and supplies it to the AMP 20 .

[0021] The AMP 20 is an amplifier that amplifies the voltage generated by the voltage conversion unit 18 , and applies the amplified voltage to the speaker 22 .

[0022] The speaker 22 outputs the additional sound based on the voltage applied from the AMP 20. Specifically, for example, the speaker 22 outputs the additional sound that changes in accordance with the control parameter after the slow processing or the delay processing. That is, for example, the speaker 22 outputs the additional sound that changes slowly or changes with a delay in response to the change in the control parameter before the slow processing or the delay processing.

[0023] FIG. 2 is a graph showing an example of control parameters before and after the slow processing.

[0024] As shown in Fig. 2, for example, when a vehicle occupant depresses the accelerator pedal of the vehicle, the accelerator opening becomes larger (see the solid line in Fig. 2). For example, when the rate of change in the accelerator opening is larger than a predetermined rate, the control unit 14 changes the volume of the additional sound at a rate smaller than the rate of change in the accelerator opening.

[0025] Specifically, for example, when the rate of change in the accelerator opening is greater than a predetermined rate, the control unit 14 slows down the change in the accelerator opening to generate an accelerator opening after slow processing (see the dashed line in FIG. 2). For example, the control unit 14 generates the accelerator opening after slow processing and transmits it to the signal generating unit 16 so that the rate of change in the accelerator opening after slow processing is equal to the predetermined rate.

[0026] The timing at which the accelerator opening degree after the slow processing starts to change is the same as the timing at which the accelerator opening degree before the slow processing starts to change, and the rate at which the accelerator opening degree after the slow processing changes is smaller than the rate at which the accelerator opening degree after the slow processing changes. In this way, the control unit 14 changes the added sound slowly with respect to the change in the control parameter before the slow processing, using the control parameter after the slow processing, which has the same timing at which it starts to change as the control parameter before the slow processing and has a slower rate of change than the control parameter before the slow processing. Furthermore, when the control parameter before the slow processing changes linearly, the control unit 14 also changes the control parameter after the slow processing linearly to change the added sound linearly. Note that, as described later, for example, when the control parameter before the slow processing changes nonlinearly, the control unit 14 generates the control parameter after the slow processing so that the control parameter changes linearly at a first rate smaller than the rate of change of the control parameter before the slow processing, and then changes linearly at a second rate smaller than the first rate, thereby changing the added sound linearly at a plurality of rates of change.

[0027] The speaker 22 outputs an additional sound whose volume or the like changes at the same rate as the rate of change in the accelerator opening degree after the slow processing generated by the control unit 14.

[0028] In this way, for example, the control unit 14 generates a control parameter after the slow processing, and outputs the additional sound from the speaker 22 based on the generated control parameter, thereby slowly changing the additional sound with respect to the change in the control parameter before the slow processing. Specifically, the control unit 14 changes the additional sound at a rate smaller than the rate of change in the control parameter before the slow processing by outputting the additional sound from the speaker 22 based on the control parameter after the slow processing. For example, the control unit 14 changes the additional sound at the same rate as a predetermined rate by making the rate of change in the control parameter after the slow processing the same as a predetermined rate.

[0029] This makes it possible to prevent the additional sound from suddenly changing when the control parameter suddenly changes, and to prevent the occupants from feeling uncomfortable due to a sudden change in the additional sound.

[0030] Also, for example, when an occupant of the vehicle depresses the accelerator pedal of the vehicle, the longitudinal acceleration increases (see the dashed line in FIG. 2). For example, when the rate of change in the longitudinal acceleration is greater than a predetermined rate, the control unit 14 changes the volume of the additional sound at a rate smaller than the rate of change in the longitudinal acceleration.

[0031] Specifically, for example, when the rate of change in the longitudinal acceleration is greater than a predetermined rate, the control unit 14 slows down the change in the longitudinal acceleration to generate a longitudinal acceleration after the slow processing (see the two-dot chain line in FIG. 2). For example, the control unit 14 generates the longitudinal acceleration after the slow processing so that the longitudinal acceleration changes linearly at a first rate smaller than the rate of change in the longitudinal acceleration before the slow processing, and then changes linearly at a second rate smaller than the first rate, that is, so that the longitudinal acceleration changes linearly sequentially at a plurality of change rates, and transmits the generated longitudinal acceleration to the signal generation unit 16.

[0032] The speaker 22 outputs an additional sound whose volume or the like changes at the same rate as the rate of change of the longitudinal acceleration after the slow processing generated by the control unit 14.

[0033] In this way, for example, the control unit 14 generates a control parameter after the slow processing, and outputs the additional sound to the speaker 22 based on the generated control parameter, thereby slowly changing the additional sound in response to the change in the control parameter before the slow processing. Specifically, the control unit 14 changes the additional sound at a first rate of change, and then changes the additional sound at a second rate smaller than the first rate, by outputting the additional sound from the speaker 22 based on the control parameter after the slow processing.

[0034] This makes it possible to prevent the additional sound from suddenly changing when the control parameter suddenly changes, and to prevent the occupants from feeling uncomfortable due to a sudden change in the additional sound.

[0035] For example, the control unit 14 may slowly change the additional sound in response to a change in the accelerator opening degree when the accelerator opening degree is reduced, such as when an occupant of the vehicle lightly depresses the accelerator pedal of the vehicle. Also, for example, the control unit 14 may slowly change the additional sound in response to a change in the longitudinal acceleration of the vehicle when the longitudinal acceleration of the vehicle is reduced.

[0036] By separately setting the rate of change when the control parameter increases, i.e., on the rising side, and the rate of change when the control parameter decreases, i.e., on the falling side, it becomes easier to appropriately slow down the control parameter even if the manner in which the control parameter changes over time differs when the control parameter increases and when it decreases, thereby further reducing the discomfort felt by the occupants.

[0037] For example, it is common that the response to the accelerator pedal depression is weaker when the accelerator pedal is depressed than when the accelerator pedal is released, and if the degree of slowness or delay of the additional sound is made larger on the rising side of the control parameter than on the falling side, the additional sound may become too slow or too delayed with respect to the actual acceleration due to the combination with the weak accelerator response when the accelerator pedal is depressed, which may cause an uncomfortable feeling. Therefore, by making the degree of slowness or delay smaller on the rising side of the control parameter than on the falling side, the uncomfortable feeling caused by the additional sound being too slow or too delayed can be suppressed.

[0038] Fig. 3 is a graph showing another example of the control parameters before and after the slow processing, Fig. 3(a) shows another example of the control parameters before and after the slow processing, and Fig. 3(b) is an enlarged view showing the part surrounded by the dashed line in Fig. 3(a).

[0039] As shown in Fig. 3, for example, the rate of change in accelerator opening is calculated by comparing accelerator openings obtained at a predetermined time interval. For example, it is determined whether or not the difference between the previous value (see X1a in Fig. 3(b)) and the current value (see X2 in Fig. 3(b)) is larger than a predetermined difference (see ΔX in Fig. 3(b)), and if it is larger, a value obtained by subtracting the predetermined difference from the previous value (see X2a in Fig. 3(b)) is calculated as the current value after the slow processing, and the slope of the line connecting the current value and the previous value represents the rate of change in accelerator opening after the slow processing.

[0040] FIG. 4 is a graph showing yet another example of the control parameters before and after the slow processing.

[0041] 4, for example, when the longitudinal acceleration is greater than a predetermined value during a predetermined period, the control unit 14 generates the longitudinal acceleration after the slow processing so that the volume of the additional sound does not decrease with the decrease in the longitudinal acceleration. Specifically, for example, the control unit 14 generates the longitudinal acceleration after the slow processing so that the rate of change during the period from when the longitudinal acceleration before the slow processing starts to decrease from a certain value to when it returns to the certain value is 0.

[0042] FIG. 5 is a graph showing an example of the control parameters before and after the delay process.

[0043] As shown in FIG. 5, for example, when the vehicle occupant depresses the accelerator pedal of the vehicle, the control parameter becomes large, and when the vehicle occupant releases the accelerator pedal of the vehicle, the control parameter becomes small (see the solid line in FIG. 5).

[0044] For example, the control unit 14 generates a delayed control parameter by delaying the control parameter received from the interface 12 by ΔT1 when the control parameter is increasing, and by delaying the control parameter by ΔT2 when the control parameter is decreasing (see the dashed line in FIG. 5). In this way, for example, the control unit 14 may change the delay time when the control parameter is increasing and when the control parameter is decreasing.

[0045] The timing at which the control parameter after the delay process starts to change is later than the timing at which the control parameter before the delay process starts to change. In this way, the control unit 14 changes the additional sound by delaying it with respect to the change in the control parameter before the delay process, using the control parameter after the delay process that starts to change later than the control parameter before the delay process.

[0046] For example, the speaker 22 outputs an additional sound whose volume or the like changes in accordance with the change in the delayed control parameter generated by the control unit 14.

[0047] In this way, for example, the control unit 14 generates a control parameter after delay processing, and outputs the additional sound from the speaker 22 based on the generated control parameter, thereby delaying the change in the additional sound relative to the change in the control parameter.

[0048] FIG. 6 is a graph showing another example of the control parameters before and after the delay process.

[0049] As shown in FIG. 6, for example, when a vehicle occupant depresses the accelerator pedal of the vehicle, the control parameter becomes large, and when the vehicle occupant releases the accelerator pedal of the vehicle, the control parameter becomes small (see the solid line in FIG. 6).

[0050] For example, the control unit 14 may predetermine a straight line (see the dashed line in FIG. 6) for determining the rate of change of the control parameter when it increases after the delay process, and predetermine the rate of change of the control parameter when it increases after the delay process based on the straight line. Also, for example, the control unit 14 may predetermine a straight line (see the dashed line in FIG. 6) for determining the rate of change of the control parameter when it decreases after the delay process, and predetermine the rate of change of the control parameter when it decreases after the delay process based on the straight line.

[0051] For example, the control unit 14 may delay the control parameter by a moving average when the control parameter increases, and may delay the control parameter by a predetermined straight line when the control parameter decreases. The control unit 14 may delay the control parameter by a moving average when the control parameter increases, and may delay the control parameter by a moving average when the control parameter decreases. The control unit 14 may delay the control parameter by a moving average when the control parameter increases, and may delay the control parameter by a secondary delay when the control parameter decreases. The control unit 14 may delay the control parameter by a secondary delay when the control parameter increases, and may delay the control parameter by a moving average when the control parameter decreases. The control unit 14 may delay the control parameter by a secondary delay when the control parameter increases, and may delay the control parameter by a moving average when the control parameter decreases. The control unit 14 may delay the control parameter by a secondary delay when the control parameter increases, and may delay the control parameter by a secondary delay when the control parameter decreases. The control unit 14 may delay the control parameter by a secondary delay when the control parameter increases, and may delay the control parameter by a secondary delay when the control parameter decreases.

[0052] For example, the speaker 22 outputs an additional sound whose volume changes in accordance with the change in the control parameter after delay processing generated by the control unit 14.

[0053] In this way, for example, the control unit 14 generates a control parameter after delay processing, and outputs the additional sound from the speaker 22 based on the generated control parameter, thereby delaying the change in the additional sound relative to the change in the control parameter.

[0054] FIG. 7 is a graph showing yet another example of the control parameters before and after the delay process.

[0055] As shown in Fig. 7, when a vehicle occupant depresses the accelerator pedal, the accelerator opening increases (see the solid line in Fig. 7). In addition, the driving torque of the vehicle changes with a delay relative to the change in the accelerator opening (see the dashed line in Fig. 7).

[0056] For example, the control unit 14 may generate the accelerator opening degree after delay processing so as to match the change in drive torque with respect to the change in the accelerator opening degree (see the dashed line in FIG. 5). Note that the accelerator opening degree after delay processing may be generated so as to match the change in the longitudinal acceleration that changes with a delay with respect to the change in the accelerator opening degree, instead of the drive torque. Although FIG. 7 only shows the accelerator opening degree when it increases, that is, on the rising side, the accelerator opening degree after delay processing may also be generated in the same manner when the accelerator opening degree decreases, that is, on the falling side.

[0057] This makes it possible to prevent the additional sound from suddenly changing in association with a sudden change in the accelerator opening, thereby suppressing the sense of discomfort caused by a sudden change in the additional sound.

[0058] The additional sound generating device 10 according to the embodiment has been described above.

[0059] The additional sound generating device 10 in the embodiment is an additional sound generating device that generates an additional sound based on a control parameter that changes in response to the operation of a vehicle, and is equipped with a control unit 14 that changes the additional sound slowly or changes the additional sound with a delay in response to the change in the control parameter.

[0060] According to this, even if the control parameter changes suddenly, the additional sound can be prevented from changing suddenly, so that the passengers can be prevented from feeling uncomfortable.

[0061] Furthermore, in the additional sound generating device 10 in the embodiment, when the rate of change of the control parameter is greater than a predetermined rate, the control unit 14 changes the additional sound at a rate smaller than the rate of change of the control parameter.

[0062] According to this, when the rate of change of the control parameter is greater than a predetermined rate, the added sound is changed at a rate smaller than the rate of change of the control parameter, thereby preventing the added sound from suddenly changing in response to a sudden change in the control parameter, and further preventing the occupants from feeling uncomfortable.

[0063] Furthermore, in the additional sound generating device 10 in the embodiment, when the rate of change of the control parameter is greater than a predetermined rate, the control unit 14 changes the additional sound at the same rate as the predetermined rate.

[0064] According to this, by previously setting the predetermined ratio to a value that makes the occupant less likely to feel uncomfortable, it is possible to further prevent the occupant from feeling uncomfortable.

[0065] Furthermore, in the additional sound generating device 10 in the embodiment, after the additional sound is changed at a first rate, the additional sound is changed at a second rate that is smaller than the first rate.

[0066] This allows the additional sound to be changed flexibly, further reducing the sense of discomfort felt by the passengers.

[0067] In the additional sound generating device 10 according to the embodiment, the control parameters include at least one of the accelerator opening and the longitudinal acceleration.

[0068] According to this, the additional sound can be changed based on at least one of the accelerator opening and the longitudinal acceleration, which are easily felt by the occupants, so that the sense of discomfort felt by the occupants can be further reduced.

[0069] (Embodiment 2) Fig. 8 is a block diagram showing a functional configuration of an additional sound generating device 10a according to embodiment 2. Fig. 9 is a graph showing an example of the relationship between the accelerator opening and the volume of the additional sound.

[0070] 8, the additional sound generating device 10a mainly differs from the additional sound generating device 10 in that it includes two interfaces 12a and 12b. In the following description, the differences from the additional sound generating device 10 will be mainly described.

[0071] The interface 12a receives only the accelerator opening, and the interface 12b receives longitudinal acceleration and the like other than the accelerator opening.

[0072] In this embodiment, the control unit 14 is provided between the interface 12a and the signal generating unit 16, but is not provided between the interface 12b and the signal generating unit 16.

[0073] In other words, the control unit 14 performs slow processing or delay processing only on the accelerator opening among the control parameters, and transmits the accelerator opening after the slow processing or delay processing to the signal generating unit 16. On the other hand, the interface 12b and the signal generating unit 16 are directly connected, and the control parameters other than the accelerator opening, such as the longitudinal acceleration, are not slow-processed or delayed by the control unit 14, and are transmitted to the signal generating unit 16 as actual measured values ​​or calculated values.

[0074] As shown in Fig. 9, in this embodiment, the control unit 14 performs slow processing of the control parameters so that the rate of change in the volume of the additional sound relative to changes in the accelerator opening is small in a low opening region where the accelerator opening is small. Also, the control unit 14 performs slow processing of the control parameters so that the rate of change in the volume of the additional sound relative to changes in the accelerator opening is large in a medium opening region where the accelerator opening is larger than the low opening region. Also, the control unit 14 performs slow processing of the control parameters so that the rate of change in the volume of the additional sound relative to changes in the accelerator opening is small in a large opening region where the accelerator opening is larger than the medium opening region.

[0075] The signal generator 16 generates a sound signal based on the control parameters after the slow processing or delay processing and other control parameters that have not been slowed or delayed. The speaker 22 outputs an additional sound based on the sound signal.

[0076] The additional sound generating device 10a according to the second embodiment has been described above.

[0077] According to the additional sound generating device 10a in the second embodiment, the additional sound is output from the speaker 22 by a sound signal generated based on the control parameters after the slow processing or delay processing and the control parameters without the slow processing or delay processing, so that the volume of the additional sound can be changed slowly in response to the change in the control parameters. This makes it possible to prevent the additional sound from suddenly changing in association with a sudden change in the control parameters, and to prevent the passengers from feeling uncomfortable due to a sudden change in the additional sound.

[0078] In addition, among the control parameters, only the accelerator opening, which represents an acceleration operation, is slowed or delayed by the control unit 14. This means that the initial operation intended to accelerate is slowed or delayed, and the additional sound is more in line with the intention to accelerate than when the phenomenon following the acceleration operation is slowed or delayed, thereby suppressing the discomfort felt by the occupants.

[0079] This reduces the volume change of the additional sound in the low throttle range where it occurs frequently, reducing the annoyance of frequent changes in the volume of the additional sound. Also, in the medium to high throttle range where there is a clear intention to accelerate, the volume change of the additional sound is made larger and the volume of the acceleration sound is increased, creating a sense of acceleration.

[0080] In addition, since the volume of the additional sound is low and reduced in the low opening range, if the delay time on the rising side is made longer than the delay time on the falling side, the increase in the volume of the additional sound will tend to be delayed due to the fact that the volume of the additional sound is reduced in the low opening range, and the sense of acceleration will not be as expected.

[0081] In this embodiment, since the volume of the additional sound is set to be reduced in the low opening range, the delay time on the rising side is made shorter than the delay time on the falling side. Therefore, even with the volume characteristics of the additional sound shown in FIG. 9, the increase in the volume of the acceleration sound does not tend to be delayed, and the above-mentioned problem of the sense of acceleration not being as expected can be eliminated.

[0082] (Embodiment 3) FIG. 10 is a block diagram showing a functional configuration of the additional sound generation device 10b according to the third embodiment.

[0083] 10, the additional sound generating device 10b mainly differs from the additional sound generating device 10 in that the control parameters taken in from the interface 12 are input to the signal generating section 16 and then to the control section 14. In the following explanation, the differences from the additional sound generating device 10 will be mainly described.

[0084] The signal generating unit 16 generates a sound signal based on the control parameters received from the interface 12 .

[0085] The control unit 14 performs slow processing or delay processing on the sound signal generated by the signal generation unit 16 to generate a slow-processed or delayed sound signal. The control unit 14 transmits the generated sound signal to the voltage conversion unit 18.

[0086] The additional sound generating device 10b according to the embodiment has been described above.

[0087] According to the additional sound generating device 10b in embodiment 3, the sound signal generated by the signal generating unit 16 can be slowed or delayed, and the additional sound can be generated inside the vehicle cabin from the speaker 22 based on the sound signal after the slow processing or delay processing. This makes it possible to prevent the additional sound from changing suddenly due to a sudden change in the control parameter, and suppresses the discomfort felt by occupants due to a sudden change in the additional sound.

[0088] In addition, since the sound signal generated by the signal generating unit 16 is slowed down, it is easier to reduce the number of objects to be delayed than when the control parameters imported from the interface 12 are slowed down, thereby suppressing an increase in the computational load and an increase in costs.

[0089] (Embodiment 4) FIG. 11 is a block diagram showing a functional configuration of the additional sound generation device 10c according to the fourth embodiment.

[0090] 11, the additional sound generating device 10c is mainly different from the additional sound generating device 10b in that the sound signal transmitted from the signal generating unit 16 is input to the voltage converting unit 18 and then input to the control unit 14. In the following explanation, the differences from the additional sound generating device 10b will be mainly described.

[0091] The voltage conversion unit 18 generates a voltage based on the sound signal transmitted from the signal generation unit 16 .

[0092] The control unit 14 performs slow processing or delay processing on the voltage generated by the voltage conversion unit 18 to generate a voltage after slow processing or delay processing. The control unit 14 transmits the generated voltage to the AMP 20.

[0093] The additional sound generating device 10c according to the embodiment has been described above.

[0094] According to the additional sound generating device 10c in the embodiment, the voltage generated by the voltage conversion unit 18 can be slowed or delayed, and the additional sound can be generated inside the vehicle cabin from the speaker 22 based on the voltage after the slow processing or delay processing. This makes it possible to prevent the additional sound from changing suddenly due to a sudden change in the control parameter, and suppresses the discomfort felt by occupants due to a sudden change in the additional sound.

[0095] In addition, since the voltage generated by the voltage conversion unit 18 is slowed down, it is easier to reduce the number of objects to be delayed than when the control parameters imported from the interface 12 are slowed down, which makes it possible to suppress an increase in the computational load and an increase in costs.

[0096] (Embodiment 5) FIG. 12 is a block diagram showing a functional configuration of an additional sound generating device 10d according to the fifth embodiment.

[0097] 12, the additional sound generating device 10d is mainly different from the additional sound generating device 10c in that the voltage transmitted from the voltage conversion unit 18 is input to the AMP 20 and then input to the control unit 14. In the following explanation, the differences from the additional sound generating device 10c will be mainly explained.

[0098] The AMP 20 amplifies the voltage transmitted from the voltage conversion unit 18 .

[0099] The control unit 14 performs slow processing or delay processing on the voltage amplified by the AMP 20 to generate a slow-processed or delayed voltage. The control unit 14 applies the generated voltage to the speaker 22.

[0100] The additional sound generating device 10d according to the embodiment has been described above.

[0101] According to the additional sound generating device 10d of the embodiment, the voltage amplified by the AMP 20 can be slowed or delayed, and the additional sound can be generated inside the vehicle cabin from the speaker 22 based on the voltage after the slow processing or delay processing. This makes it possible to prevent the additional sound from changing suddenly due to a sudden change in the control parameter, and suppresses the discomfort felt by occupants due to a sudden change in the additional sound.

[0102] In addition, since the voltage amplified by AMP20 is slowed down, it is easier to reduce the number of objects to be delayed than when the control parameters imported from the interface 12 are slowed down, which prevents an increase in the computational load and also prevents an increase in costs.

[0103] (Other embodiments, etc.) Although the additional sound generating device according to one or more aspects has been described based on the embodiment, the present disclosure is not limited to the embodiment. As long as it does not deviate from the gist of the present disclosure, various modifications conceived by a person skilled in the art to the present embodiment may also be included within the scope of the present disclosure. [Industrial Applicability]

[0104] The present disclosure can be used in an additional sound generating device that generates additional sound, etc. [Explanation of symbols]

[0105] 10, 10a, 10b, 10c, 10d Additional sound generating device 12,12a,12b Interface 14 Control section 16 Signal Generation Unit 18 Voltage conversion section 20 AMP 22 Speaker

Claims

1. An additional sound generating device that generates an additional sound based on a control parameter that changes in response to an operation of a vehicle, a control unit that changes the additional sound slowly at the same timing as the change in the control parameter, and when a rate of change in the control parameter is greater than a predetermined rate, the control unit slowly and linearly changes the additional sound at a rate smaller than the rate of change in the control parameter or a first rate that is the same as the predetermined rate, and then linearly changes the additional sound at a second rate smaller than the first rate, and further sets a rate of change on the rising side of the control parameter and a rate of change on the falling side of the control parameter individually, and sets a degree of slowness smaller on the rising side of the control parameter than on the falling side of the control parameter, thereby generating the additional sound from a speaker in the vehicle cabin based on the sound signal after the slow processing, and suppresses a sudden change in the additional sound due to a sudden change in the control parameter, and suppresses a sense of discomfort given to occupants by a sudden change in the additional sound. Additional sound generating device.

2. The control parameters include at least one of an accelerator opening and a longitudinal acceleration. The additional sound generating device according to claim 1 .

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