DE102009021673B4 - Headrest and seat with headrest - Google Patents

Abstract

Headrest (105, 106) for use in a vehicle comprising at least one side part (110, 111, 205), wherein the at least one side part (110, 111, 205) of the headrest (105, 106) at least partially over the ear of a user is arranged,- wherein the headrest (105, 106) and/or the at least one side part (110, 111, 205) is designed to absorb sound,- wherein the headrest (105, 106) comprises at least one loudspeaker which can be controlled in this way is that background noise can be at least partially compensated for,- a microphone being provided in the area of the headrest (105, 106), by means of which the background noise can be at least partially compensated for,- with the headrest (105, 106) and/or the at least one side part (110, 111, 205) includes several materials in a material composite that provide a predetermined soundproofing for certain frequency ranges.

Description

The invention relates to a headrest, a seat with a headrest and a vehicle with at least one such seat.

From the DE 102 41 132 A1 a headrest for use in a vehicle is already known which comprises a side part which is arranged at least partially over the ear of a user.

Furthermore is off JP 2008 - 154 921 A a headrest for a vehicle is known with a noise-absorbing core layer. The disadvantage here is that speech intelligibility within the vehicle suffers due to the noise-absorbing headrest, because, for example, statements made by passengers in the back seat of the vehicle are also muffled by the driver or front passenger and are therefore poorly or hardly understood.

The damping of airborne noise in the vehicle interior reduces both the mostly disruptive medium and high-frequency driving noise (rolling noise, wind noise, drive train noise, exhaust system noise) and the energy in speech noise. The reduction in speech sound can lead to communication difficulties between people sitting in different positions.

the DE 195 16 012 C1 shows a protective hood for a driver's seat with sound-absorbing material on the inside and the DE 197 54 168 A1 a headrest with swiveling side elements equipped with an integrated speaker and microphone.

The object of the invention is to avoid the disadvantages mentioned above and in particular to reduce interference or background noise while at the same time enabling good speech communication between the passengers.

This object is solved according to the features of the independent patent claims. Developments of the invention also result from the dependent claims.

To solve the problem, a headrest for use in a vehicle is proposed, comprising at least one side part, the at least one side part of the headrest being arranged at least partially over the ear, in particular the external auditory canal, of a user.

It can thus be achieved that the user only perceives background noise to a reduced extent and speech communication between the user and other people in the vehicle is still possible.

In particular, the at least one side part is arranged at a lateral distance, at least partially covering the ear. This covering relates to the side view of the ear, with the at least one side part preferably not touching the ear itself in the covering area.

The headrest and/or the at least one side part is designed to absorb sound, in particular to absorb background noise.

The headrest and/or the at least one side part comprises a number of materials that can be used to absorb or reduce background noise. These materials are provided in a composite material which, for example, provides a specified soundproofing for certain frequency ranges. These frequency ranges are preferably bands that correspond to background noise in a vehicle.

The headrest has at least one loudspeaker that can be controlled in such a way that background noise can be at least partially compensated for.

Such an active system has the advantage that specific frequency ranges can be (partially) damped. In addition, frequency ranges, e.g. those in which speech is to be understood, can be amplified. In particular, microphones can be provided at different locations in the vehicle, which allow useful signal recognition, e.g. of voice data, and output such voice data via the at least one loudspeaker.

At the same time, the background noise can be reduced in correlation to a signal from a noise sensor. Here, the background noise in the vicinity of a microphone arranged in the area of the headrest is reduced.

A further development is that the headrest has a left-hand side part and a right-hand side part, with the left-hand side part and the right-hand side part being designed to be adjustable independently of one another.

The user can adjust the side parts of the headrest according to individual wishes, so that the ratio between useful noise and background noise is comfortable for him. In particular, a noise level that is pleasant for the user can be achieved by adjusting the side parts due to a sound-absorbing function of the side parts.

Another development is that the left side panel and the right side panel in the direction a windscreen of a vehicle can be arranged asymmetrically.

This makes it possible, for example, for the side parts to be optimally aligned with regard to useful sound (e.g. in the form of speech) reflected from a windscreen.

In particular, it is a further development that the at least one side part is made in one piece with the headrest.

For example, the headrest can be firmly connected to at least one of the side parts. Optionally, only one side part can be moved.

• - ein Vlies, insbesondere ein Kunststoff-Faser-Vlies;
• - einen Schaum, insbesondere einen PU-Schaum;
• - ein poröses Absorbermaterial.

A further development is that the headrest and/or the at least one side part comprises at least one of the following materials:

• - A fleece, in particular a plastic fiber fleece;
• - a foam, in particular a PU foam;
• - a porous absorber material.

Absorbing or noise-reducing materials can also be provided as film covers and/or adhesive layers. In particular, the mass of a noise-reducing material can be designed with regard to a frequency range to be absorbed.

The mass is in particular a combination of a mass of the film and/or the adhesive layer and a spring made of a porous material or foam, so that tunable absorption is achieved at a resonant frequency of this spring-mass system. The spring can be of any design, in particular the spring can have dynamic resilience.

As part of an additional development, the headrest is part of a seat with a backrest, the backrest being designed to absorb sound, in particular to absorb background noise.

In one development, a microphone is provided in the area of the headrest, which can be used to at least partially compensate for the background noise.

It is also a development that the background noise can be at least partially compensated for by means of a sensor for detecting at least part of the background noise.

Another development consists in the sensor being a sensor for detecting an engine speed or an engine noise.

The above-mentioned object is also achieved using a method for reducing background noise with a headrest according to one of claims 1 to 11, the proportion of background noise being at least partially compensated for depending on background noise and/or a speech signal.

In particular, a processing unit (e.g. a processor unit) is provided, which is set up in such a way that the proportion of the background noise is at least partially reduced depending on a detected background noise and/or the speech signal.

The above object is also achieved by means of a seat comprising a headrest as described herein.

Furthermore, the object is achieved using a vehicle that has at least one such seat.

Exemplary embodiments of the invention are illustrated and explained schematically below with reference to the drawings.

• 1 eine symbolische Draufsicht auf eine Fahrerkabine mit Fahrer, Beifahrer und zwei Passagieren auf einer Rückbank, wobei die Sitze des Fahrers und des Beifahrers Kopfstützen mit je einem Mittelteil sowie einem rechten und einem linken Seitenteil aufweisen;
• 2 einen Sitz in einer Seitenansicht, wobei der Sitz eine Kopfstütze mit einem Seitenteil aufweist, welches Seitenteil seitlich über dem Ohr eines Benutzers angeordnet ist.

Show it:

• 1 a symbolic top view of a driver's cab with driver, front passenger and two passengers on a back seat, the seats of the driver and front passenger having headrests, each with a central part and a right and a left side part;
• 2 a seat in a side view, the seat having a headrest with a side part, which side part is arranged laterally over the ear of a user.

Speech spoken by humans has a strong spatial directivity and spreads out in the vehicle interior like an acoustic free field. In an open field, the exact transmission path (e.g. reflections on windows, roof lining, side paneling parts) is relevant. The position of an absorber therefore has a decisive influence on the transmission of speech, e.g. between the rear and front seats of the vehicle.

The absorption in the vehicle interior is perceived as different depending on the location with regard to the spatial impression created. The approach proposed here also makes use of the fact that absorption placed close to the ear can create an impression of calm, isolation or relaxation.

For example, it can be assumed that, in contrast to the speech signals, the background noise tends to propagate as a diffuse field.

The approach proposed here enables sound or noise to be absorbed in a vehicle interior, with a specified upper limit of a speech intelligibility index being maintained.

For example, depending on the series, i.e. depending on individual vehicles, the upper limit of the speech intelligibility index can be assumed to be 75%. The speech intelligibility index can be calculated according to [THOMA Gerhard & BISPING Rudolf, "A computerized method for measurement of speech intelligibility in the car using natural speech sounds", Proceedings of the EuroNoise 98, Munich, 532-538, 1998] or [THOMA Gerhard & BISPING Rudolf, "Speed and RPM controlled changes of speech intelligibility: A new computerized method for measuring the communicative quality of car interior sound", Inter-noise 2003, N821, Seogwipo (Korea), 2003].

For example, with a speech intelligibility index of 75%, good speech understanding is assumed, particularly between passengers in the back seat and passengers in the front seats of the vehicle.

If additional absorption is achieved with the headrest, a significant proportion of background noise can be attenuated without significantly impairing speech intelligibility.

Porous materials, e.g. nonwovens or foams, can be used as porous absorbers or resonance absorbers in various structures to dampen airborne noise inside the vehicle.

The following can be used as the absorption material: A fleece, for example a synthetic fiber fleece or a PU foam. Materials of this type can be processed, for example, as film covers or adhesive layers, in which case the bulk of the materials can be designed with regard to the frequency range to be absorbed. For example, a 15mm thick light fleece with approx. 600g/m ² can be used.

With absorbing headrests, an optimum between a reduction in background noise and sufficiently good speech intelligibility can be achieved. In particular, the headrest can have foldable side parts. The user can adjust these side parts individually and thus adjust an absorption close to the ear according to his individual wishes.

It is also an option that a rear seat backrest, for example the back of the rear seat backrest, is designed to be absorbent. In vehicles with a (partially) open luggage compartment, e.g. Touring or station wagon vehicles, a defined absorption of background noise can be achieved without significantly impairing speech intelligibility between passengers in the rear seats and passengers in the front seats

For example, a lattice girder structure can be covered with a decoration that is backed by an absorber. It is also possible that a seat foam is used as an absorber and is accordingly designed for specific frequency ranges.

The absorption can be predetermined by the selection of a transmittance or a flow resistance of the decorative covering and/or the absorption of the material arranged behind the decorative covering.

1 shows a schematic plan view of a driver's cab 101 of a motor vehicle with a steering wheel 102, a driver 103, a front passenger 104 and two passengers 107 and 108 placed on a rear seat.

Examples are in 1 each a top view of a headrest 105 of the driver 103 and a headrest 106 of the passenger 104 is shown. The headrests 105, 106 each have a central part 109 and a right side part 110 and a left side part 111. The side parts 110, 111 are designed to be movable relative to the central part 109. In particular, the side parts 110, 111 can be positioned independently of one another relative to the central part 109 (for example asymmetrically in the direction of the windscreen of the vehicle), so that pleasant noise absorption is achieved with good speech intelligibility. Accordingly, such headrests can also be provided for the passengers 107, 108 (not shown).

2 shows a seat 201 in side view. The seat 201 includes a seat bottom 202, a backrest 203, and a headrest having a center portion 204 and a left side portion 205 (shown phantom) (the right side portion is not shown for clarity). The left side part 205 preferably at least partially covers the ear or the external auditory canal of a user. It should be noted here that for the dimensioning of the seat 201 and/or headrest, a standardized user, in particular a standardized or average head size of a user can be used in order to be able to specify a measure that is suitable for a large number of users.

The user can preferably adjust the side part 205 in such a way that it causes a corresponding absorption of background sound or noise. The right side panel (not shown) and the left side panel 205 may be asymmetrically oriented toward a windshield. This ensures that a large proportion of the useful sound can be captured by the headrest or by the side parts of the headrest. Since the spoken language spreads almost evenly in the interior of the vehicle according to a free field and is reflected, for example, on the windshield, the proposed seat 201 ensures speech intelligibility while at the same time efficiently absorbing background noise. In particular, the backrest 203 can be modified in such a way that it efficiently filters out background noise, for example in a vehicle without a fully partitioned trunk.

It should be noted here that said background noise can include any noise of the vehicle (driving noise, road noise, noise from the exhaust system). Depending on vehicle type and/or user preference, it is also possible to attenuate certain types of noise to different degrees. For example, a noise from the exhaust system can be dampened more or less, in particular by means of an active system, than a road noise.

It is also possible that an active system for noise compensation is provided in the seat 201, e.g. in the headrest of the seat 201. The active system can have at least one loudspeaker, for example, which is controlled by means of a signal processor and amplifier in such a way that certain frequencies are at least partially compensated. If necessary, other frequency ranges could even be amplified or at least not (or hardly) attenuated. This additionally improves speech understanding between passengers of a vehicle.

It is also possible to provide loudspeakers and microphones in such a way that, in the sense of a feedback system near the ear, low-frequency noise in particular is eliminated, with medium- and high-frequency (speech) sound components preferably remaining largely or completely unchanged.

Alternatively, a combination of an active system and a passive system can be used. For example, background noise can be reduced by means of the active system and targeted absorption by porous absorbers, while specifically coordinated layer structures (comprising e.g. a decoration, an adhesive and/or a foam) are provided for medium to high frequencies.

The approach proposed here enables an optimized reduction in the noise level in the vehicle interior with simultaneously sufficiently high speech intelligibility, particularly between passengers in different rows of seats.

A further advantage is that the proposed optimization can be carried out efficiently with little effort in terms of costs, installation space and weight by applying the proposed measures to the headrests 105, 106 of the vehicle.

It is also advantageous that the user finds appropriately designed headrests 105, 106 with absorption close to the ear relaxing, or that the user can adjust a degree of absorption individually. In this way, a feeling of security and acoustic isolation can advantageously be conveyed.

If perforated materials, e.g. perforated leather, are used in connection with the headrest 105, 106, the perforation can be designed with regard to optimized absorption, since the headrest 105, 106 is only exposed to low mechanical loads.

Reference List

101

driver's cab (of a vehicle)

102

steering wheel

103

driver

104

passenger

105

headrest

106

headrest

107

passenger

108

passenger

109

Central part of the headrest

110

right side part of the headrest

111

left side part of the headrest

201

Seat

202

seat

203

backrest

204

Central part of the headrest

205

left side part of the headrest

Claims (10)

Headrest (105, 106) for use in a vehicle - comprising at least one side part (110, 111, 205), wherein the at least one side part (110, 111, 205) of the headrest (105, 106) is arranged at least partially over the ear of a user, - wherein the headrest (105, 106) and/or the at least one side part (110, 111, 205) is designed to absorb sound, - wherein the headrest (105, 106) comprises at least one loudspeaker which can be controlled in such a way that background noise can be at least partially compensated for, - a microphone being provided in the area of the headrest (105, 106), by means of which the background noise can be at least partially compensated for, - Wherein the headrest (105, 106) and/or the at least one side part (110, 111, 205) comprises a plurality of materials in a composite material which provide a predetermined soundproofing for specific frequency ranges. headrest (105, 106). claim 1 with a left side part (111) and with a right side part (110), the left side part (111) and the right side part (110) being adjustable independently of one another. headrest (105, 106). claim 2 , in which the left side part (111) and the right side part (110) can be arranged asymmetrically in the direction of a windscreen of a vehicle. headrest (105, 106). claim 1 , wherein the at least one side part (110, 111, 205) is made in one piece with the headrest (105, 106). Headrest (105, 106) according to one of the preceding claims, in which the headrest (105, 106) and/or the at least one side part (110, 111, 205) comprises at least one of the following materials: - a fleece, - a foam, - a porous absorber material. Headrest (105, 106) according to one of the preceding claims, in which the headrest (105, 106) is part of a seat (201) with a backrest (203), the backrest (203) being designed to absorb sound. Headrest (105, 106) according to one of the preceding claims, in which the background noise can be at least partially compensated for by means of a sensor for detecting at least part of the background noise. headrest (105, 106). claim 7 , in which the sensor is a sensor for detecting an engine speed or an engine noise. Seat (201) comprising a headrest (105, 106) according to one of Claims 1 until 8th . Vehicle with at least one seat (201) according to claim 9 .

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