Patent Description:
Embodiments relate to a passive auto-orienting loudspeaker assembly, such as for a vehicle seat.

Motor vehicles, such as automobiles, typically have multiple loudspeakers in a fixed arrangement to output audio (e.g., music, audiobooks, etc.) for a driver and passengers in the vehicle. In automotive audio systems, the directionality of loudspeakers is often a major driver for acoustic performance, and fixed loudspeakers are limited in that they cannot change the direction of their audio output. While the inherent directivity of a loudspeaker can only be changed via the design of the transducer, the orientation of the loudspeaker can have just as much of an impact on the sound field and the on quality of the listening experience.

Often designers attempt to arrange loudspeakers within a vehicle so that they are pointed directly at listeners, but this can backfire as no two listeners are of the exact same height, body size, head size, etc. In addition, many vehicle surfaces can move and change, such as seats that recline and/or change position, or armrests that lift and lower. In "sound zone"-type experiences where multiple listeners are trying to listen to multiple types of media, maintaining the correct and intended directionality of a loudspeaker can greatly influence the effectiveness of the entire audio system. As an example, loudspeaker A might be optimized to play audio content only for listener A, and loudspeaker B might be optimized to play audio content only for listener B. However, if loudspeaker A ends up pointed at listener B, listener B would be hearing content from the undesired "zone" and a poor listening experience will result.

Publications <CIT> discloses a system for tuning an audio system based on a seat position. The system senses and measures any changes in seat position form a default seat position and adjusts a set of modified tuning parameters to be applied to the audio system based on the modified seat position. Publication <CIT> discloses a loudspeaker system that comprises a loudspeaker, an imaging device for capturing images, a processor for detecting a face in the captured images, and a motor that is connected to the loudspeaker and can modify a sound emitting direction of the loudspeaker based on the face data. Publication <CIT> discloses a detachable control device that includes an operation member, a detachable interface configured to attach the detachable control device to a handle of a gimbal device, a wireless communication circuit, and a controller configured to detect an operation on the operation member, and generate control data according to the operation. The control data includes at least one of gimbal orientation control data for controlling an attitude of a gimbal of the gimbal device or camera function control data for controlling a photographing device mounted at the gimbal to perform a corresponding function. Publication <CIT> discloses a sound reproduction device that includes a superdirective speaker having a first surface, and an attachment part having a second surface opposed to the first surface. The first surface has a convex face, and the second surface has a concave face which can come into contact with the convex face. A curvature of the convex face is set larger than that of the concave face. A direction of emitting a sound wave of the superdirective speaker can be adjusted by making the convex face move along the concave face. Publication <CIT> discloses a photographic payload augmentation device includes a ring defining a ring body for mounting onto a photographic payload device and a plurality of weight plugs. The ring body has a plurality of recesses so that a respective weight may be selectively inserted within a respective recess. The ring body may be cylindrically shaped and may also include an inner sidewall, an outer sidewall, a top face and a bottom face. Each recess is defined by a recess sidewall and terminates at a bottom wall located intermediate the top face and the bottom face. The ring body may still further define a plurality of apertures wherein a respective aperture is located between respective recess sidewalls of adjacent recesses of the plurality of recesses. The bottom wall may also define a plurality of slots wherein a respective slot communicates with a respective recess of the plurality of recesses.

In one or more embodiments, a vehicle seat comprises a loudspeaker assembly for a vehicle seat that includes a housing configured to be received within a rear side of the vehicle seat, an enclosure rotatably mounted to the housing, the enclosure having a nonuniform weight distribution, and a loudspeaker disposed within the enclosure and having an initial orientation. A change in an angular position of the vehicle seat with respect to a vehicle floor results in a passive rotation of the enclosure with respect to the housing to substantially maintain the initial orientation of the loudspeaker as the angular position of the vehicle seat changes, wherein the nonuniform weight distribution of the enclosure causes the loudspeaker assembly to automatically and passively rotate with respect to the housing and the vehicle seat.

As described above, in order to provide an optimal listening environment, it is desirable to have loudspeakers mounted in vehicle components be maintained in their intended orientation towards vehicle occupants even when those vehicle components change position. In one solution to this problem, motorized or actuated systems may be implemented, but with the disadvantages of greater cost, weight, and complexity which may render such solutions undesirable.

Accordingly, embodiments disclosed herein describe a solution for automatically orienting a loudspeaker towards a specific region of interest without the assistance of motors, actuators, or other active processes. Instead, the disclosed loudspeaker assembly uses passive, mechanical means to maintain the intended and/or optimized orientation of loudspeakers within a vehicle, wherein this passive mechanism may be attached to the vehicle seat structure and may be responsive to the seat recline mechanism.

It is understood that directional terms as noted herein (e.g., front, rear, behind, top, bottom, back, etc.) simply refer to the orientation of various components as illustrated in the accompanying figures and the manner in which components may be oriented relative to the vehicle. Such terms are provided for context and understanding of the embodiments disclosed herein and are not intended to be limiting.

<FIG> generally depicts a vehicle audio system <NUM> in an interior cabin <NUM> of a vehicle <NUM>. The interior cabin <NUM> includes a plurality of vehicle seats <NUM>, namely a plurality of front seats <NUM> positioned in a first row <NUM> and a plurality of rear seats <NUM> positioned in a second row <NUM>. Each vehicle seat <NUM> may include a headrest <NUM> and a backrest <NUM>, and each vehicle seat <NUM> (and its headrest <NUM> and backrest <NUM>) has a rear side <NUM> that faces a rear end <NUM> of the vehicle <NUM>. It is recognized that the number of vehicle seats and rows in the interior cabin <NUM> of the vehicle <NUM> may vary based on the particular type of vehicle <NUM>. For example, the interior cabin <NUM> may have additional rows including additional vehicle seats positioned behind the second row <NUM> toward the rear end <NUM> of the vehicle <NUM>.

The vehicle audio system <NUM> may include a plurality of loudspeakers positioned within the interior cabin <NUM>. In particular, a loudspeaker assembly <NUM> may be mounted in one or more of the vehicle seats <NUM>, specifically on the rear side <NUM> thereof, and configured to radiate sound toward the rear end <NUM> of the vehicle. With reference to <FIG> and <FIG>, in one non-limiting example the loudspeaker assembly <NUM> may be mounted in the backrest <NUM> of one or both of the front seats <NUM> for directing audio to the rear seat(s) <NUM> and its vehicle occupants. A loudspeaker assembly <NUM> could alternatively or additionally be mounted in the rear side <NUM> of the headrest <NUM> of any vehicle seat <NUM>, as exemplary illustrated in <FIG>. It is recognized that the number of loudspeaker assemblies <NUM> positioned within each of the headrests <NUM> and/or backrests <NUM> may vary based on the desired criteria of a particular configuration of the vehicle <NUM> and the vehicle audio system <NUM>. Although the audio system <NUM> and loudspeaker assemblies <NUM> are generally described herein as being implemented in the rear side <NUM> of the front seats <NUM> for directing sound to vehicle occupants in the rear seats <NUM>, it is understood that the audio system <NUM> is also applicable to implementation of one or more loudspeaker assemblies <NUM> in any vehicle seat <NUM>, such as a rear side <NUM> of the rear seats <NUM> for a third or subsequent row of vehicle seats <NUM> and its vehicle occupants, depending on the configuration of the vehicle <NUM>.

With reference to <FIG>, the loudspeaker assembly <NUM> includes a loudspeaker <NUM> disposed within an enclosure <NUM>. Although not illustrated in detail, it is understood that the loudspeaker <NUM> includes the typical components (e.g. motor assembly, voice coil, spider, cone, etc.) for generating sound in response to the electrical signals received. The enclosure <NUM> may include electronics and wiring (not shown), and may be either sealed or ported. While illustrated herein as being generally rectangular, the enclosure <NUM> is not limited to this configuration.

The loudspeaker assembly <NUM> further includes a housing <NUM> that may be received or embedded in the rear side <NUM> of the headrest <NUM> or backrest <NUM> in the vehicle seat <NUM>, such as the front seat <NUM>. Accordingly, the vehicle seat <NUM> may include a recess <NUM> formed therein, wherein the recess <NUM> is sized and configured to a least partially receive the housing <NUM>. While the housing <NUM> is depicted as having a generally curved or hemispherical configuration herein, other shapes and configurations of the housing <NUM> are fully contemplated.

The enclosure <NUM> is rotatably mounted to the housing <NUM>, as described further below. The enclosure <NUM> may be mounted in the housing <NUM> so that the loudspeaker <NUM> lies generally flush with the rear side <NUM> of the headrest <NUM> or backrest <NUM>. In another embodiment, enclosure <NUM> may be mounted so that the loudspeaker <NUM> may lie inward from the rear side <NUM> or outward from the rear side <NUM>. In one or more embodiments, the installation position of the loudspeaker assembly <NUM> may be configured such that vehicle impact safety requirements are met. This may be accomplished by, for example, recessing the loudspeaker assembly <NUM> into the foam or other structural housing of the headrest <NUM> or backrest <NUM> to minimize impact with any portion of the vehicle occupant's body. It is contemplated that the fabric or leather of the rear side <NUM> of the headrest <NUM> or backrest <NUM> may cover the housing <NUM> such that only the loudspeaker <NUM> and enclosure <NUM> are be visible to vehicle occupants.

In one or more embodiments, the geometry of the housing <NUM> may serve as a waveguide to control the directivity of the sound field generated by the loudspeaker <NUM>. For example, the housing <NUM> may be deepened and the enclosure <NUM> may be mounted in the housing <NUM> set inward from the rear side <NUM> to improve isolation of one vehicle occupant's sound field from that of other vehicle occupants. Referring to <FIG>, instead of the generally centered location of the loudspeaker assemblies <NUM> shown with respect to the rear side <NUM> of the vehicle seat <NUM>, the loudspeaker assemblies <NUM> may be mounted horizontally off-center on the vehicle seat <NUM>, such as mounted offset closer to the vehicle doors <NUM>. By increasing the separation of the loudspeaker assemblies <NUM> on adjacent vehicle seats <NUM> in this manner, individual sound zones may be preserved for the vehicle occupants.

As referenced above, the loudspeaker assembly <NUM> includes a mechanical mounting interface between the enclosure <NUM> and the housing <NUM> which allows the enclosure <NUM> to change position or rotate with respect to the housing <NUM> as the vehicle seat <NUM> changes its angle of orientation (e.g. is moved in a more reclined direction or is moved in a more upright direction). Accordingly, the position of the enclosure <NUM> automatically and passively compensates for a change in angular position of the vehicle seat <NUM> in order to continue to aim the loudspeaker <NUM> at the original or desired target point within the vehicle <NUM>. As the angular position of the vehicle seat <NUM> (e.g. front seat <NUM>) is changed, a passive mechanism accounts for the angle of reclination of the vehicle seat <NUM> and automatically adjusts the orientation angle of the enclosure <NUM>. The result is a loudspeaker <NUM> that is always pointing towards the same, desired region of interest, regardless of the angle of the vehicle seat <NUM>.

With reference to <FIG>, a loudspeaker assembly <NUM> is illustrated according to one or more embodiments, wherein the enclosure <NUM> may have a nonuniformly distributed weight such that the enclosure <NUM> and contained loudspeaker <NUM> are biased to remain in a desired orientation as the angular position of the vehicle seat <NUM> is adjusted. The nonuniform weight distribution of the enclosure <NUM> may be accomplished by a material excess or increased material density at a bottom portion <NUM> of the enclosure <NUM> (e.g., closest to the vehicle floor <NUM>) as compared with an opposite, top portion <NUM> of the enclosure <NUM>. Alternatively, the nonuniform weight distribution of the enclosure <NUM> may be achieved by a weight member <NUM> associated with the bottom portion <NUM> of the enclosure, such as embedded within or coupled or affixed to the bottom portion <NUM>. In one or more embodiments, the weight member <NUM> may be constructed from a non-magnetic material and is not limited to the shape or configuration depicted herein. Other designs which result in nonuniform weight distribution of the enclosure <NUM> at the bottom portion <NUM> thereof are also fully contemplated.

The enclosure <NUM> can be rotatably mounted to the housing <NUM>, such as via pivot shafts <NUM> rotatably coupling the enclosure <NUM> to the housing <NUM> on each side of the enclosure <NUM>. The nonuniform weight distribution of the enclosure <NUM> will cause the enclosure <NUM> to rotate with respect to the housing <NUM> about the pivot shafts <NUM> when the angle of the vehicle seat <NUM> is changed, thus maintaining the orientation of the loudspeaker assembly <NUM> as the vehicle seat <NUM> is raised or reclined. While the pivot shafts <NUM> are illustrated as supporting the enclosure <NUM> for rotation about approximately a central horizontal axis therethrough, the pivot shafts <NUM> could alternatively support the enclosure <NUM> for rotation with respect to the housing <NUM> and the vehicle seat <NUM> about a different horizontal or vertical location. Furthermore, rotational or translational movement about other axes is also contemplated. In one or more embodiments, it is also contemplated that the enclosure <NUM> could be removably mounted to the housing <NUM>.

Returning to <FIG>, the loudspeaker assembly <NUM> may have an initial or desired orientation when the vehicle seat <NUM> is in a first or neutral angular position A with respect to the vehicle floor <NUM>. In the first angular position A of the vehicle seat <NUM>, the loudspeaker <NUM> may have a desired orientation toward a rear seat <NUM> and its occupant. When the vehicle seat <NUM> is reclined to a second angular position B (a decreased angle with respect to the vehicle floor <NUM> as compared with angular position A) or raised to a third angular position C (an increased angle with respect to the vehicle floor <NUM> as compared with angular position A), the nonuniform weight distribution of the enclosure <NUM> causes the loudspeaker assembly <NUM> to automatically and passively rotate with respect to the housing <NUM> and the vehicle seat <NUM>. As a result of this rotation, the loudspeaker <NUM> remains in the desired orientation (e.g., the orientation when in angular position A) as the vehicle seat <NUM> is reclined or raised. Thus, for a loudspeaker assembly <NUM> mounted in a front seat <NUM>, the loudspeaker <NUM> remains positioned accurately with respect to the rear seat <NUM> and its occupant regardless of the angular position of the front seat <NUM>.

The vehicle audio system <NUM> may be used by different vehicle occupants at different times, where each vehicle occupant may have unique physical characteristics, such as height or hearing ability. As such, it may be desirable to optimize the initial orientation of the loudspeaker <NUM> relative to a particular vehicle occupant. Accordingly, in one or more embodiments, it is contemplated that a selective initial positioning of the enclosure <NUM> may be possible. As illustrated in <FIG>, this may be accomplished, for example, by configuring the weight member <NUM> to be movable, such as slidable or otherwise repositionable, with respect to the bottom portion <NUM> of the enclosure <NUM>. For example, if the weight member <NUM> is set at a central position <NUM> of the bottom portion <NUM> (<FIG>), then an angle of the loudspeaker <NUM> may be approximately equal to <NUM> degrees with respect to the vehicle floor <NUM>. However, if the weight member <NUM> is set at a front position <NUM> of the bottom portion <NUM> (<FIG>), then the angle of the loudspeaker <NUM> may be less than <NUM> degrees with respect to the vehicle floor <NUM>, and if the weight member <NUM> is at a back position <NUM> of the bottom portion <NUM> (<FIG>), then the angle of the loudspeaker <NUM> may be greater than <NUM> degrees with respect to the vehicle floor <NUM>. Accordingly, the position of the weight member <NUM> can be selected by the vehicle occupant for optimal initial positioning and sound field acoustics suitable to his or her individual characteristics, and then this selected, optimal orientation or angle is maintained as the vehicle seat <NUM> is reclined or raised.

As illustrated schematically in <FIG>, the vehicle audio system <NUM> may include an audio controller <NUM> that is operably coupled to each loudspeaker assembly <NUM>. The audio controller <NUM> may generally include any number of hardware-based processors and memory and may be used for controlling various parameters of each loudspeaker <NUM> and the resulting acoustical signal. The audio controller <NUM> may generally process information used in connection with an AM radio, FM radio, satellite radio, navigation system, user interface, display, wireless communication with mobile devices via Bluetooth, WiFi or other wireless protocols, etc. The audio controller <NUM> may include any number of channels, where each channel may be coupled to a respective loudspeaker <NUM> via an audio amplifier (not shown) for transmitting the audio signal to the loudspeakers <NUM>. with mobile devices via Bluetooth, WiFi or other wireless protocols, etc. The audio controller <NUM> may include any number of channels, where each channel may be coupled to a respective loudspeaker <NUM> via an audio amplifier (not shown) for transmitting the audio signal to the loudspeakers <NUM>.

The one or more loudspeaker assemblies <NUM> disclosed herein can be used to provide surround or ambience audio content for vehicle occupants. For example, the audio content may provide entertainment through music or dialog, or provide information through instructions or directions. The vehicle audio system <NUM> may be used as the primary speakers for a sound system or may be added to a conventional audio system to improve the spatial characteristics of stereo or surround sound systems in the vehicle <NUM>.

While the audio system <NUM> and loudspeaker assemblies <NUM> are described herein with reference to a vehicle <NUM> and illustrated in an automobile, the embodiments described herein can also apply to other types of vehicles, such as boats, airplanes, trains and the like, and the vehicle may include any number of loudspeaker assemblies <NUM>. Furthermore, instead of a vehicle, the loudspeaker assembly <NUM> could be utilized in such home environments as seating in a home theater.

Claim 1:
A vehicle seat (<NUM>) comprising a loudspeaker assembly (<NUM>), the loudspeaker assembly (<NUM>) comprising:
a housing (<NUM>) arranged to be received within a rear side (<NUM>) of the vehicle seat (<NUM>);
an enclosure (<NUM>) rotatably mounted to the housing (<NUM>), the enclosure (<NUM>) having a nonuniform weight distribution; and
a loudspeaker (<NUM>) disposed within the enclosure (<NUM>) and having an initial orientation, characterized in that a change in an angular position of the vehicle seat (<NUM>) with respect to a vehicle floor results in a passive rotation of the enclosure (<NUM>) with respect to the housing (<NUM>) to substantially maintain the initial orientation of the loudspeaker (<NUM>) as the angular position of the vehicle seat (<NUM>) changes, wherein the nonuniform weight distribution of the enclosure (<NUM>) causes the loudspeaker assembly (<NUM>) to automatically and passively rotate with respect to the housing (<NUM>) and the vehicle seat (<NUM>).