Steering apparatus and sound output system

A steering apparatus according to an aspect of the present disclosure includes a rim member, a center member connected to a steering shaft at a rotation center of the rim member, a first sound output apparatus provided on a front surface of the rim member or the center member, and a first rim chamber unit provided in the rim member and in communication with a space behind the first sound output apparatus.

FIELD

The embodiments discussed herein are related to a steering apparatus and a sound output system.

BACKGROUND

Conventionally, various installation methods have been proposed as installation methods of speakers (sound output apparatuses) of sound output systems in vehicles.

SUMMARY

According to an aspect of an embodiment, a steering apparatus according to an aspect of the present disclosure includes a rim member, a center member connected to a steering shaft at a rotation center of the rim member, a first sound output apparatus provided on a front surface of the rim member or the center member, and a first rim chamber unit provided in the rim member and in communication with a space behind the first sound output apparatus.

DESCRIPTION OF EMBODIMENT

For example, Japanese Unexamined Utility Model Application Publication No. S63-183786 suggests a method for installing speakers in a steering apparatus manipulated by a driver. According to this method of installation, sounds can be reliably conveyed to the driver. However, when the speakers are disposed in the steering apparatus, the space that can be secured behind the speakers is limited. This affects the frequency characteristics of the output sound, which may make it difficult to, for example, output a low frequency sound.

According to an aspect, the frequency characteristics of the sound emitted from such a sound output apparatus disposed in a steering apparatus are desired to be improved.

Hereinafter, embodiments are described with reference to the accompanying drawings. In this specification and the drawings, constituent elements that have substantially the same functional configurations are denoted with the same reference numerals, and duplicate description is omitted.

First Embodiment

<System Configuration of Sound Output System>

First, a system configuration of a sound output system on a vehicle according to the first embodiment is explained.FIG.1is a drawing illustrating an example of a system configuration of the sound output system according to the first embodiment.

As illustrated inFIG.1, a sound output system120includes a sound signal processing apparatus100and a steering apparatus110provided with a sound output apparatus111. The sound signal processing apparatus100and the sound output apparatus111are connected to be able to transmit and receive signals.

In the sound signal processing apparatus100, a sound generating program and the like are installed. The sound signal processing apparatus100functions as a sound generating unit101by executing the sound generating program. The sound generating unit101generates a sound output signal, and transmits the generated sound output signal to the sound output apparatus111. The sound output apparatus111outputs the sound output signal transmitted by the sound generating unit101.

<Example of Installation of Sound Output System>

Next, an example of installation of each apparatus of the sound output system120in the vehicle is explained. In the sound output system120installed in the vehicle, for example, the functions of the sound signal processing apparatus100are implemented in a navigation apparatus.

FIG.2is a drawing illustrating an example of installation of each apparatus of the sound output system120in the vehicle according to the first embodiment. As illustrated inFIG.2, for example, a navigation apparatus in which the functions of the sound signal processing apparatus100are implemented is arranged in a center console of the vehicle. Also, for example, the speakers serving as the sound output apparatus111are disposed at a position indicated inFIG.2of the steering apparatus110manipulated by the driver of the vehicle.

The steering apparatus110includes: a rim member201in a ring shape configured to be grabbed by the driver; and a center member202connected to a steering shaft (not illustrated) at a center of rotation of the rim member201. In the example ofFIG.2, the speakers serving as the sound output apparatus111are disposed at a lower position of the center member202(specifically, at a lower position when the steering apparatus110is at an angle of 0 degrees).

As illustrated inFIG.2, in the present embodiment, a direction from the right-hand side to the left-hand side in the lateral direction of the vehicle is defined as an x axis direction, and a direction from the lower side to the upper side in the height direction of the vehicle is defined as a z axis direction. Further, although not illustrated inFIG.2, in the present embodiment, a direction from the front to the rear in the longitudinal direction of the vehicle is defined as a y axis direction.

<Hardware Configuration of Sound Signal Processing Apparatus>

Next, the hardware configuration of the sound signal processing apparatus100is explained.FIG.3is a drawing illustrating an example of a hardware configuration of a sound signal processing apparatus.

As illustrated inFIG.3, the sound signal processing apparatus100includes a CPU (Central Processing Unit)301, ROM (Read Only Memory)302, and RAM (Random Access Memory)303. The CPU301, the ROM302, and the RAM303constitute what is termed as a computer.

In addition, the sound signal processing apparatus100includes an auxiliary storage device304, an operation apparatus305, a display apparatus306, a connection apparatus307, a communication apparatus308, and a drive apparatus309. Each of the pieces of hardware of the sound signal processing apparatus100are connected with each other via the bus310.

The CPU301is an arithmetic processing unit executing various kinds of programs (for example, a sound generating program, and the like) installed in the auxiliary storage device304.

The ROM302is a non-volatile memory. The ROM302functions as a main storage device that stores various programs and the like which the CPU301uses to execute various programs installed in the auxiliary storage device304. Specifically, the ROM302stores boot programs such as BIOS (Basic Input and Output System) and EFI (Extensible Firmware Interface).

The RAM303is a volatile memory such as DRAM (Dynamic Random Access Memory) or SRAM (Static Random Access Memory). The RAM303functions as a main storage device that provides a work area in which various programs installed in the auxiliary storage device304are expanded when the programs are executed by the CPU301.

The auxiliary storage device304is an auxiliary storage device that stores various programs and parameters used for execution of the various programs.

The operation apparatus305receives input of various instructions from the driver. The operation apparatus305may have various button switches, a predetermined or given operation device, or a touch panel integrally formed with the display apparatus306.

The connection apparatus307makes a connection with the sound output apparatus111, and sends, to the sound output apparatus111, a sound output signal generated by the CPU301executing various programs. The connection with the sound output apparatus111may be made with wires or may be made by short-range wireless communication such as Bluetooth (registered trademark). The communication apparatus308is a communication device for communicating with the network.

The drive apparatus309is a device for setting the recording medium320. Examples of the recording medium320include a CD-ROM, a flexible disk, a magneto-optical disk, and the like that record information either optically, electrically, or magnetically. Further, examples of the recording medium320include semiconductor memory such as ROM or flash memory that electrically records information.

For example, various programs are installed to the auxiliary storage device304by setting the distributed recording medium320on the drive apparatus309and causing the drive apparatus309to read various programs recorded in the recording medium320.

Next, the configuration of the steering apparatus110is described. In this case, in particular, the configuration related to the installation of the sound output apparatus111is described. In the steering apparatus110according to the first embodiment, not only the inside of the center member202is hollowed out but also the inside of the rim member201is hollowed out in order to secure a space sufficient for emitting a low frequency sound when the sound output apparatus111is installed. Accordingly, on the negative side in the y axis direction with respect to the sound output apparatus111, not only the space in the center member202but also the closed space along the circular direction of the rim member201can be secured, when the sound output apparatus111is installed on the steering apparatus110. In other words, with the steering apparatus110according to the first embodiment, a configuration approximately equivalent to a configuration of a closed stereo apparatus can be achieved. Accordingly, the steering apparatus110according to the first embodiment can improve the frequency characteristics of the sound, and can output a low frequency sound. Hereinafter, the configuration examples (three configuration examples) of the steering apparatus according to the first embodiment is described.

(1) First Configuration Example of Steering Apparatus

FIGS.4A to4Care drawings illustrating a first configuration example of a steering apparatus according to a first embodiment. Among them,FIG.4Ais a schematic diagram illustrating a closed stereo apparatus.FIG.4Bincludes a front view and a right side view illustrating an external configuration of the steering apparatus110achieving a configuration approximately equivalent to a closed stereo apparatus.

As illustrated inFIG.4B, the sound output apparatus111is installed oriented toward the driver (i.e., toward the positive side in the y axis direction) at a lower position on the front surface of the center member202including a rotation center404of the rim member201.

FIG.4Cillustrates a front sectional view of the steering apparatus110taken along an alternate long and short dash line402ofFIG.4B, and a side sectional view of the steering apparatus110taken along an alternate long and short dash line401ofFIG.4B.

As illustrated inFIG.4C, in the center member202, a space (first center chamber unit)411is provided on the negative side in the y axis direction with respect to the position where the sound output apparatus111is provided. Also, in the rim member201, a space (first rim chamber unit)412is provided throughout the entire circumference of the ring shape of the rim member201.

Furthermore, the first center chamber unit411and the first rim chamber unit412are in communication with each other. Accordingly, on the negative side in the y axis direction with respect to the position where the sound output apparatus111is provided, the closed space sufficient for emitting a low frequency sound can be secured.

(2) Second Configuration Example of Steering Apparatus

FIGS.5A and5Bare drawings illustrating a second configuration example of the steering apparatus according to the first embodiment. Among them,FIG.5Aillustrates a steering apparatus510achieving a configuration approximately equivalent to a closed stereo apparatus, wherein a first rim chamber unit512is formed in a part of a ring shape of a rim member201.

As illustrated inFIG.5A, as long as the sound output apparatus111can secure a space sufficient for emitting a low frequency sound, the first rim chamber unit512does not have to be provided along the entire circumference of the ring shape in the rim member201. In other words, the first rim chamber unit512is provided in a part of the ring shape in the rim member201.

FIG.5Billustrates a steering apparatus520achieving a configuration approximately equivalent to a closed stereo apparatus, wherein a first rim chamber unit512is formed in a part of a ring shape in the rim member201. In the case ofFIG.5B, the sound output apparatus111is arranged on the left-hand side of the center member202in the x axis direction. Accordingly, the first center chamber unit411is provided on the left-hand side of the center member202in the x axis direction. The first rim chamber unit512is provided in the left-hand side portion as a part of the ring shape of the rim member201.

(3) Third Configuration Example of Steering Apparatus

In the examples ofFIGS.4A to4CandFIGS.5A and5B, the configuration examples of the steering apparatuses where the sound output system120includes a single sound output apparatus111have been explained. However, the sound output system120may have two sound output apparatuses.

FIGS.6A and6Bare drawings illustrating a third configuration example of the steering apparatus according to the first embodiment. Among them,FIG.6Aincludes a front view and a right side view illustrating an external configuration of a steering apparatus610achieving a configuration approximately equivalent to a closed stereo apparatus and provided with two sound output apparatuses.

As illustrated inFIG.6A, for example, two sound output apparatuses may be arranged line-symmetrically with respect to a straight line passing through a rotation center404(i.e., a straight line (not illustrated) in the z axis direction). Specifically, the two sound output apparatuses may be arranged, as sound output apparatuses611,612, at the right and left positions of the front surface of the center member202of the steering apparatus610. Still alternatively, the two sound output apparatuses may be arranged, as sound output apparatuses621_1,622_1, on the front surface of the rim member201of the steering apparatus610. Still alternatively, the two sound output apparatuses may be arranged, as sound output apparatuses621_2,622_2, on the front surface of the rim member201of the steering apparatus610. Still alternatively, the two sound output apparatuses may be arranged, as sound output apparatuses621_3,622_3, on the front surface of the rim member201of the steering apparatus610.

For example, the two sound output apparatuses may be arranged point-symmetrically with respect to the rotation center404. Specifically, the two sound output apparatuses may be arranged, as sound output apparatuses621_1,622_3, on the front surface of the rim member201of the steering apparatus610. Alternatively, the two sound output apparatuses may be arranged, as sound output apparatuses621_3,622_1, on the front surface of the rim member201of the steering apparatus610.

FIG.6Billustrates a front sectional view of the steering apparatus610taken along an alternate long and short dash line402ofFIG.6A, and a side sectional view of the steering apparatus610taken along an alternate long and short dash line401ofFIG.6A.

As illustrated inFIG.6B, in the center member202, the space (the first center chamber unit)631_1is provided on the negative side in the y axis direction with respect to the position where the sound output apparatus611is disposed. A space (second center chamber unit)632_1is provided on the negative side in the y axis direction with respect to the position where the sound output apparatus612is disposed.

A space (first rim chamber unit)631_2in communication with the first center chamber unit631_1is provided in a part of the inside of the rim member201along the ring shape of the rim member201. Further, a space (second rim chamber unit)632_2in communication with the second center chamber unit632_1is provided in a part of the inside of the rim member201along the ring shape of the rim member201. In this case, the total volume of the first center chamber unit631_1and the first rim chamber unit631_2is substantially the same as the total volume of the second center chamber unit632_1and the second rim chamber unit632_2.

The first rim chamber unit631_2and the second rim chamber unit632_2are not in communication with each other, and the spaces independent from each other are formed.

Specifically, a separation wall is provided between the first rim chamber unit631_2and the second rim chamber unit632_2.

Accordingly, on the negative side in the y axis direction with respect to the positions where the two sound output apparatuses are provided line-symmetrically or point-symmetrically, closed spaces sufficient for emitting a low frequency sound are secured.

As can be understood from the above explanation, the steering apparatus according to the first embodiment includes:a rim member in a ring shape configured to be grabbed by a driver;a center member connected to a steering shaft at a rotation center of the rim member; anda sound output apparatus or two sound output apparatuses configured to emit a sound signal and disposed on a front surface of the center member or a front surface of the rim member,wherein the steering apparatus includes a rim chamber unit or rim chamber units disposed inside of the rim member along the ring shape of the rim member, the rim chamber unit or the rim chamber units being in communication with a space behind the sound output apparatus or respective spaces behind two sound output apparatuses.

In this manner, the space is formed in the rim member. Therefore, with the steering apparatus according to the first embodiment, a closed space sufficient for emitting a low frequency sound can be secured behind the sound output apparatus. As a result, the frequency characteristics of the sound emitted from the sound output apparatus can be improved.

Second Embodiment

In the above first embodiment, a sound output system transmitting a sound output signal generated by a sound generating unit to one or two sound output apparatuses has been explained. In contrast, in a sound output system according to the second embodiment, a sound signal generated by a sound generating unit is processed by a signal processing unit and transmitted to two sound output apparatuses, so that the sound is localized at a predetermined or given position of the driver.

<System Configuration of Sound Output System>

First, a system configuration of the sound output system in the vehicle according to the second embodiment is explained.FIG.7is a drawing illustrating an example of a system configuration of a sound output system according to the second embodiment.

As illustrated inFIG.7, the sound output system720includes: a sound signal processing apparatus700; and a steering apparatus710provided with sound output apparatuses (i.e., a first sound output apparatus and a second sound output apparatus)711,712. The sound signal processing apparatus700and the sound output apparatuses711,712are connected to be able to transmit and receive signals.

On the sound signal processing apparatus700, not only the sound generating program but also a signal processing program are installed. The sound signal processing apparatus700functions as a sound generating unit701and a signal processing unit702by executing the programs.

The sound generating unit701generates a sound signal and inputs the generated sound signal into the signal processing unit702. The signal processing unit702generates a sound output signal by performing signal processing on the sound signals received from the sound generating unit701, and transmits the sound output signal to the sound output apparatuses711,712. The sound output apparatuses711,712output the sound output signal (i.e., a first sound output signal and a second sound output signal) transmitted from the signal processing unit702.

<Functional Configuration of Sound Signal Processing Apparatus>

Next, a functional configuration of the sound signal processing apparatus700is explained.FIG.8is a drawing illustrating an example of a functional configuration of the sound signal processing apparatus of the sound output system according to the second embodiment. As illustrated inFIG.8, the signal processing unit702of the sound signal processing apparatus700includes localization filters801,802, and a crosstalk cancellation unit810.

The localization filter801is a filter designed to allow the driver820to feel as if the sounds of the sound signals generated by the sound generating unit701come from the right-hand side of the driver820. The sound signals processed by the localization filter801are input to the crosstalk cancellation unit810.

The localization filter802is a filter designed to allow the driver820to feel as if the sounds of the sound signals generated by the sound generating unit701come from the left-hand side of the driver820. The sound signals processed by the localization filter802are input to the crosstalk cancellation unit810.

The crosstalk cancellation unit810multiplies the sound signals processed by the localization filters801,802by parameters A to D. The parameters A to D are calculated on the basis of the following Expression (1).

In the above Expression (1), “hFR” denotes a measured value representing transfer characteristics of sound from the sound output apparatus711to the right ear of the driver820. “hFL” denotes a measured value representing transfer characteristics of sound from the sound output apparatus712to the left ear of the driver820. “hCR” denotes a measured value representing transfer characteristics of sound from the sound output apparatus711to the left ear of the driver820. “hCL” denotes a measured value representing transfer characteristics of sound from the sound output apparatus712to the right ear of the driver820.

The multiplier811multiplies the sound signal processed by the localization filter801by the parameter A. The multiplier812multiplies the sound signal processed by the localization filter802by the parameter B.

The multiplier813multiplies the sound signal processed by the localization filter801by the parameter C. The multiplier814multiplies the sound signal processed by the localization filter802by the parameter D.

The adder815adds the sound signals multiplied by the parameters A, B by the multiplier811and the multiplier812, respectively, and transmits the sum as a sound output signal to the sound output apparatus711. The adder816adds the sound signals multiplied by the parameters C, D by the multiplier813and the multiplier814, respectively, and transmits the sum as a sound output signal to the sound output apparatus712.

Therefore, the sound signal processing apparatus700can localize the sound of the sound signal generated by the sound generating unit701to the right ear and/or the left ear of the driver820.

Next, a configuration of the steering apparatus710is explained. In the steering apparatus710according to the second embodiment, when the sound output apparatuses711,712are installed, two portions are hollowed out in the center member202in order to secure respective spaces sufficient for emitting low frequency sounds. Furthermore, two portions are hollowed out in the rim member201. Accordingly, on the negative side in the y axis direction with respect to the sound output apparatuses711,712, not only the space in the center member202but also the closed space along the circular direction of the rim member201can be secured, when the sound output apparatuses711,712are installed on the steering apparatus710. In other words, with the steering apparatus710according to the second embodiment, a configuration approximately equivalent to a configuration of a closed stereo apparatus can be achieved.

Accordingly, the steering apparatus710according to the second embodiment can improve the frequency characteristics of the sound, and can output a low frequency sound. Hereinafter, the configuration examples (two configuration examples) of the steering apparatus according to the second embodiment are described.

(1) First Configuration Example of Steering Apparatus

FIGS.9A and9Bare drawings illustrating a first configuration example of the steering apparatus according to the second embodiment. Among them,FIG.9Aincludes a front view and a right side view illustrating an external configuration of the steering apparatus710achieving a configuration approximately equivalent to a closed stereo apparatus.

As illustrated inFIG.9A, the sound output apparatuses711,712are installed, toward the driver (i.e., toward the positive side in the y axis direction), on the front surface of the center member202including the rotation center404of the rim member201. At the right and left positions on the front surface of the center member202, the sound output apparatuses711,712are arranged line-symmetrically with respect to a straight line passing through the rotation center404(i.e., a straight line (not illustrated) in the z axis direction).

FIG.9Billustrates a front sectional view of the steering apparatus710taken along an alternate long and short dash line402ofFIG.9A, and a side sectional view of the steering apparatus710taken along an alternate long and short dash line401ofFIG.9A.

As illustrated inFIG.9B, in the center member202, a space (first center chamber unit)631_1is provided on the negative side in the y axis direction with respect to the position where the sound output apparatus711is installed. A space (second center chamber unit)632_1is provided on the negative side in the y axis direction with respect to the position where the sound output apparatus712is installed.

Also, a space (first rim chamber unit)631_2in communication with the first center chamber unit631_1is provided in a part of the inside of the rim member201along the ring shape of the rim member201. Further, a space (second rim chamber unit)632_2in communication with the second center chamber unit632_1is provided in a part of the inside of the rim member201along the ring shape of the rim member201. In this case, the total volume of the first center chamber unit631_1and the first rim chamber unit631_2is substantially the same as the total volume of the second center chamber unit632_1and the second rim chamber unit632_2.

The first rim chamber unit631_2and the second rim chamber unit632_2are not in communication with each other, and the spaces independent from each other are formed. Specifically, a separation wall is provided between the first rim chamber unit631_2and the second rim chamber unit632_2.

Accordingly, on the negative side in the y axis direction with respect to the positions where the sound output apparatuses711,712are arranged line-symmetrically, closed spaces sufficient for emitting low frequency sounds are secured.

(2) Second Configuration Example of Steering Apparatus

FIGS.10A and10Bare drawings illustrating a second configuration example of the steering apparatus according to the second embodiment. The second configuration example ofFIGS.10A and10Bare different fromFIGS.9A and9Bin that in a steering apparatus1010, sound output apparatuses711,712are installed toward the driver (i.e., toward the positive side in the y axis direction) on the front surface of the rim member201, not on the front surface of the center member202. However, likeFIGS.9A and9B, the sound output apparatuses711,712are arranged line-symmetrically with respect to a straight line passing through the rotation center404(i.e., a straight line (not illustrated) in the z axis direction).

FIG.10Billustrates a front sectional view of the steering apparatus1010taken along an alternate long and short dash line402ofFIG.10A, and a side sectional view of the steering apparatus1010taken along an alternate long and short dash line401ofFIG.10A.

FIG.10Bis different fromFIG.9Bin that, because the sound output apparatuses711,712are arranged on the front surface of the rim member201, the first center chamber unit631_1and the second center chamber unit632_1are not provided in the center member202.

In this manner, when spaces sufficient for emitting a low frequency sound can be secured with only the first rim chamber unit631_2and the second rim chamber unit632_2provided in the rim member201, the sound output apparatuses711,712may be disposed on the front surface of the rim member201.

As explained with reference toFIGS.6A and6B, as long as the sound output apparatuses711,712are arranged line-symmetrically, the sound output apparatuses711,712may be arranged at other positions.

As can be understood from the above explanation, the sound output system according to the second embodiment includes:a steering apparatus including a rim member in a ring shape grabbed by a driver and a center member connected to a steering shaft at a rotation center of the rim member,wherein two sound output apparatuses emitting sounds of sound signals are arranged line-symmetrically with respect to a center line passing through the rotation center (i.e., a straight line in the z axis direction) on a front surface of the center member or a front surface of the rim member,the steering apparatus includes a rim chamber unit provided in the rim member along the ring shape of the rim member and in communication with respective spaces behind the two sound output apparatuses, andthe sound output system includes a signal processing unit to process a sound signal generated by a sound generating unit to localize sounds emitted from the sound output apparatuses to a desired portion of the driver.

In this manner, the spaces are formed in the rim member. Therefore, with the sound output system according to the second embodiment, closed spaces sufficient for emitting a low frequency sound can be secured behind the two respective sound output apparatuses. As a result, the frequency characteristics of the sounds emitted from the two sound output apparatuses can be improved. Furthermore, with the sound output system according to the second embodiment, the sounds emitted from the two sound output apparatuses can be localized to a predetermined or given portion of the driver.

Third Embodiment

In the above second embodiment, when sound signals processed to be localized to a predetermined or given portion of the driver are emitted from the two sound output apparatuses, a configuration approximately equivalent to a configuration of a closed stereo apparatus is achieved on the steering apparatus.

In contrast, in the third embodiment, ports or vents are additionally provided in association with the two respective sound output apparatuses, so that a configuration approximately equivalent to a configuration of a bass reflex stereo apparatus can be achieved in a steering apparatus, which amplifies low frequency sound by Helmholtz resonance. Hereinafter, the difference of the third embodiment from the above second embodiment is mainly explained.

FIGS.11A to11Care drawings illustrating a configuration example of a steering apparatus according to the third embodiment. Among them,FIG.11Ais a schematic diagram illustrating a bass reflex stereo apparatus.FIG.11Bincludes a front view and a right side view illustrating an external configuration of the steering apparatus1110achieving a configuration approximately equivalent to a bass reflex stereo apparatus.

The steering apparatus1110is different fromFIG.9Bin that a port (first port)1111is formed, at a position of a distance DR-Rfrom the sound output apparatus711, in the front surface of the center member202. Also, in the steering apparatus1110, a port (second port)1112is formed, at a position of a distance DL-Lfrom the sound output apparatus712, in the front surface of the center member202.

The ports1111,1112have a tubular shape in the y axis direction. In other words, the ports1111,1112are arranged in the same orientation as the sound output apparatus711,712, respectively. The length of the tube and the size of the cross sectional area of the tube of the port1111depend on the total volume of the first center chamber unit631_1and the first rim chamber unit631_2. The length of the tube and the size of the cross sectional area of the tube of the port1112depend on the total volume of the second center chamber unit632_1and the second rim chamber unit632_2.

InFIG.11B, the ports1111,1112are assumed to be arranged at positions satisfying the following expressions with respect to the sound output apparatuses711,712.
DL-L<DL-R
DR-R<DR-L

FIG.11Cillustrates a front sectional view of the steering apparatus1010taken along an alternate long and short dash line402ofFIG.11B, and a side sectional view of the steering apparatus1010taken along an alternate long and short dash line401ofFIG.11B. InFIG.11C, the first center chamber unit631_1, the second center chamber unit632_1, the first rim chamber unit6312, and the second rim chamber unit632_2have already been explained with reference toFIG.9B, and therefore, explanation thereabout is omitted here.

As can be understood from the above explanation, the steering apparatus according to the third embodiment includes:a rim member in a ring shape grabbed by a driver and a center member connected to a steering shaft at a rotation center of the rim member,wherein two sound output apparatuses emitting sounds of sound signals are arranged line-symmetrically with respect to the center line passing through the rotation center (i.e., a straight line in the z axis direction) on a front surface of the center member,ports are provided in proximity to the two sound output apparatuses on the front surface of the center member,a first center chamber unit and a second center chamber unit are provided in the center member and behind the sound output apparatuses and the ports, andthe steering apparatus further includes a first rim chamber unit in communication with the first center chamber unit and a second rim chamber unit in communication with the second center chamber unit, the first rim chamber unit and the second rim chamber unit being provided in the rim member along the ring shape of the rim member.

In this manner, the space is formed in the rim member. Therefore, with the steering apparatus according to the third embodiment, the low frequency sound can be amplified by the Helmholtz resonance while spaces sufficient for the two sound output apparatuses to emit low frequency sounds are secured. As a result, the frequency characteristics of the sounds emitted from the two sound output apparatuses can be improved.

In the third embodiment, the ports1111,1112are provided in proximity to the sound output apparatuses711,712, on the basis of the assumption that signal processing for localizing the sounds to a predetermined or given portion of the driver820is performed. However, in a case where the signal processing for localizing the sounds to a predetermined or given portion of the driver820is not performed, the ports1111,1112do not have to be provided in proximity to the sound output apparatuses711,712. The ports1111,1112may be provided on the back surface of the center member202.

Fourth Embodiment

In the third embodiment, a configuration approximately equivalent to a bass reflex stereo apparatus is achieved on the steering apparatus. In contrast, in the fourth embodiment, a configuration approximately equivalent to a configuration of a back loaded horn stereo apparatus is achieved on a steering apparatus. Hereinafter, the difference of the fourth embodiment from the above third embodiment is mainly explained.

FIGS.12A to12Care drawings illustrating a configuration example of a steering apparatus according to the fourth embodiment. Among them,FIG.12Ais a schematic diagram illustrating a back loaded horn stereo apparatus.FIG.12Bincludes a front view and a right side view illustrating an external configuration of a steering apparatus1210achieving a configuration approximately equivalent to a back loaded horn stereo apparatus.

The steering apparatus1210inFIG.12Bis different from the steering apparatus1110inFIG.11Bin that ports1211,1212are provided on the front surface of the center member202. The ports1211,1212are different from the ports1111,1112illustrated inFIG.11Bin the propagation path of the sound from the sound output apparatuses to the ports.

FIG.12Cillustrates a front sectional view of the steering apparatus1210taken along an alternate long and short dash line402ofFIG.12A, and a side sectional view of the steering apparatus1210taken along an alternate long and short dash line401ofFIG.12A.

As illustrated inFIG.12C, a partitioning unit1201defining a propagation path of sound is provided in the first center chamber unit1221_1and the first rim chamber unit1221_2. Likewise, a partitioning unit1202defining a propagation path of sound is provided in the second center chamber unit1222_1and the second rim chamber unit1222_2.

Therefore, for example, the sound emitted from the rear of the sound output apparatus712propagates in the second center chamber unit1222_1and the second rim chamber unit1222_2along the arrows, and is output through the port1212to the outside. InFIG.12C, the arrows indicate the propagation path of the sound emitted from the rear of the sound output apparatus712. The arrows indicating the propagation path of the sound emitted from the rear of the sound output apparatus711are omitted. However, it is to be understood that the sound emitted from the rear of the sound output apparatus711propagates through a similar propagation path, and is output through the port1211to the outside.

In this case, as illustrated inFIG.12C, in the second rim chamber unit12222, the size of area of the cross section of the partitioning unit1202gradually increases according to the order of propagation of the sound.

Specifically, the border portion (i.e., throat portion) between the second center chamber unit1222_1and the second rim chamber unit1222_2has the smallest size of area of the cross section. In the second rim chamber unit12222, the cross section gradually increases as illustrated in cross-sectional shapes1231to1233.

For example, in the cross-sectional shape1231, an area i is an area through which the sound emitted from the rear of the sound output apparatus712passes first. In the cross-sectional shape1231, an area ii is an area through which the sound emitted from the rear of the sound output apparatus712passes after having passed through the area i.

In the cross-sectional shape1232, an area iii is an area through which the sound emitted from the rear of the sound output apparatus712passes after having passed through the area ii. In the cross-sectional shape1232, an area vi is an area through which the sound emitted from the rear of the sound output apparatus712finally passes.

In the cross-sectional shape1233, an area iv is an area through which the sound emitted from the rear of the sound output apparatus712passes after having passed through the area iii. In the cross-sectional shape1233, an area v is an area through which the sound emitted from the rear of the sound output apparatus712passes after having passed through the area iv.

As illustrated in the cross-sectional shapes1231to1233, according to the order of propagation of sound, the size of area of the cross section increases in the following order: the area i, the area ii, the area iii, the area iv, the area v, and finally the area vi. In this manner, by configuring the cross-sectional shapes1231to1233according to the order of propagation of the sound, a configuration approximately equivalent to a configuration of a back loaded horn stereo apparatus can be achieved in the steering apparatus1210.

As can be understood from the above explanation, a configuration approximately equivalent to a configuration of a back loaded horn stereo apparatus according to the fourth embodiment includes:a rim member in a ring shape grabbed by a driver and a center member connected to a steering shaft at a rotation center of the rim member,wherein two sound output apparatuses emitting sounds of sound signals are arranged line-symmetrically with respect to a center line passing through the rotation center (i.e., a straight line in the z axis direction) on a front surface of the center member,ports are provided in proximity to the two respective sound output apparatuses in the front surface of the center member,a first center chamber unit and a second center chamber unit are provided in the center member and behind the sound output apparatuses and the ports,a first rim chamber unit in communication with the first center chamber unit and a second rim chamber unit in communication with the second center chamber unit, the first rim chamber unit and the second rim chamber unit being provided in the rim member along the ring shape of the rim member,partitioning units defining propagation paths of sounds from the sound output apparatuses to the ports are provided in the first center chamber unit, the second center chamber unit, the first rim chamber unit, and the second rim chamber unit, andsizes of areas of cross sections of the sound propagation paths of the sounds defined by the partitioning units are configured to gradually increase according to order of the propagation of the sounds.

In this manner, the space is formed in the rim member. Therefore, with the steering apparatus according to the fourth embodiment, a configuration approximately equivalent to a configuration of a back loaded horn stereo apparatus can be achieved while spaces sufficient for the two sound output apparatuses to emit low frequency sounds are secured. As a result, the frequency characteristics of the sounds emitted from the two sound output apparatuses can be improved.

In the fourth embodiment, the ports1211,1212are provided in proximity to the sound output apparatuses711,712, on the basis of the assumption that signal processing for localizing the sounds to a predetermined or given portion of the driver820is performed. However, in a case where the signal processing for localizing the sounds to a predetermined or given portion of the driver820is not performed, the ports1211,1212do not have to be provided in proximity to the sound output apparatuses711,712. The ports1211,1212may be provided on the back surface of the center member202.

Further, in the fourth embodiment, the propagation paths of the sounds are defined by the partitioning units, but for example, the propagation paths of the sound may be defined by inserting a tube of which size of area of the cross section gradually increases according to the order of propagation of the sound in the rim member201.

Fifth Embodiment

In the fourth embodiment, a configuration approximately equivalent to a configuration of a back loaded horn stereo apparatus is achieved in the steering apparatus. In contrast, in the fifth embodiment, a configuration approximately equivalent to a drone cone speaker apparatus is achieved in a steering apparatus. Hereinafter, the difference of the fifth embodiment from the above fourth embodiment is mainly explained.

FIGS.13A to13Care drawings illustrating a configuration example of a steering apparatus according to the fifth embodiment. Among them,FIG.13Ais a schematic diagram illustrating a drone cone speaker apparatus.FIG.13Bincludes a front view and a right side view illustrating an external configuration of a steering apparatus1310achieving a configuration approximately equivalent to a drone cone speaker apparatus.

The steering apparatus1310inFIG.13Bis different from the steering apparatus1210inFIG.12Bin that passive radiators (i.e., a first passive radiator, a second passive radiator)1311,1312are provided on the front surface of the center member202. The passive radiators1311,1312are arranged in the same orientation as the sound output apparatus711,712, respectively. The passive radiators1311,1312are similar to the sound output apparatuses711,712but the passive radiators1311,1312do not have any electromagnetic circuit. The passive radiators1311,1312operate with vibration of air in the first center chamber unit631_1and the second center chamber unit632_1.

The size and the mass of the passive radiator1311depend on the total volume of the first center chamber unit631_1and the first rim chamber unit631_2. The size and the mass of the passive radiator1312depend on the total volume of the second center chamber unit632_1and the second rim chamber unit632_2.

FIG.13Cillustrates a front sectional view of the steering apparatus1310taken along an alternate long and short dash line402ofFIG.13B, and a side sectional view of the steering apparatus1310taken along an alternate long and short dash line401ofFIG.13B. InFIG.13C, the first center chamber unit6311, the second center chamber unit632_1, the first rim chamber unit631_2, and the second rim chamber unit632_2have been explained inFIG.9B, and therefore, explanation thereabout is omitted here.

As can be understood from the above explanation, the steering apparatus according to the fifth embodiment includes:a rim member in a ring shape grabbed by a driver and a center member connected to a steering shaft at a rotation center of the rim member,wherein two sound output apparatuses emitting sounds of sound signals are arranged line-symmetrically with respect to a center line passing through the rotation center (i.e., a straight line in the z axis direction) on a front surface of the center member,passive radiators are arranged in proximity to the two respective sound output apparatuses on the front surface of the center member,a first center chamber unit and a second center chamber unit are provided in the center member and behind the sound output apparatuses and the passive radiators, andthe steering apparatus further includes a first rim chamber unit in communication with the first center chamber unit and a second rim chamber unit in communication with the second center chamber unit, the first rim chamber unit and the second rim chamber unit being provided in the rim member along the ring shape of the rim member.

In this manner, the space is formed in the rim member, and therefore, with the steering apparatus according to the fifth embodiment, a configuration approximately equivalent to a drone cone speaker apparatus is achieved while spaces sufficient for the two sound output apparatuses to emit low frequency sounds are secured. As a result, the frequency characteristics of the sounds emitted from the two sound output apparatuses can be improved.

In the fifth embodiment, the passive radiators1311,1312are provided in proximity to the sound output apparatuses711,712, on the basis of the assumption that signal processing for localizing the sounds to a predetermined or given portion of the driver820is performed. However, in a case where the signal processing for localizing the sounds to a predetermined or given portion of the driver820is not performed, the passive radiators1311,1312do not have to be provided in proximity to the sound output apparatuses711,712. Alternatively, the passive radiators1311,1312may be provided on the back surface of the center member202.

Sixth Embodiment

In the first to fifth embodiments, the rim member of the steering apparatus110has a single ring shape. However, the rim member of the steering apparatus does not have to have a single ring shape.

FIG.14is a figure illustrating an external shape of a steering apparatus according to the sixth embodiment. The steering apparatus1410as illustrated inFIG.14is provided with rim members1401,1402at the right and left-hand sides, which form two ring shapes. In addition, the steering apparatus1410includes a center member202connected to a steering shaft at a rotation center404of the rim members1401,1402.

Therefore, in a manner similar to the second to fifth embodiments, the steering apparatus1410can have sound output apparatuses711,712oriented toward the driver (i.e., toward the positive side in the y axis direction) on the front surface of the center member202including the rotation center404. The sound output apparatuses711,712are arranged line-symmetrically with respect to a straight line passing through the rotation center404(i.e., a straight line in the z axis direction) on the front surface of the center member202.

Therefore, in a manner similar to the second to fifth embodiments, the first center chamber unit, the second center chamber unit, the first rim chamber unit, and the second rim chamber unit can be provided, and effects similar to the second to fifth embodiments can be obtained.

It should be noted that the present disclosure is not limited to the configurations described above. Constituent elements other than the constituent elements described above can be combined with the constituent elements described in the above embodiments. The configurations can be changed without deviating from the gist of the present disclosure, and can be defined as appropriate according to the form of its application.

The frequency characteristics of the sound emitted from the sound output apparatuses installed in a steering apparatus can be improved.