Abstract:
A method for mounting a loudspeaker carrier in a vehicle. The method includes providing a loudspeaker carrier and providing an expandable material. The method further includes arranging the expandable material between the loudspeaker carrier and a mounting site on bodywork of the vehicle and activating the expandable material such that the material expands, forming a foam structure, and causes the loudspeaker to be secured to the bodywork.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims priority to EP Application No. 13 168 304.7 filed on May 17, 2013, the disclosure of which is incorporated in its entirety by reference herein. 
     TECHNICAL FIELD 
     The disclosure relates to a loudspeaker carrier, a loudspeaker assembly and a method for mounting a loudspeaker carrier in a vehicle. 
     BACKGROUND 
     Vehicles such as automobiles may include an infotainment system with one or more loudspeakers. The loudspeakers may be mounted at various sites within the vehicle, for example in the dashboard, in the door panels and/or underneath the seats, depending on the available space and number and type of loudspeakers of the infotainment system. 
     Commonly a loudspeaker is mounted in a cavity formed within the vehicle bodywork. The cavity may be fabricated by inserting a deformable plastic precursor in an opening in the vehicle bodywork and expanding the plastic precursor to form the cavity. The loudspeaker module may be screwed into the structure so that the diaphragm of the loudspeaker is positioned above the opening to the cavity. 
     Further arrangements and methods for mounting a loudspeaker in a vehicle which are simple to perform are, however, desirable. 
     SUMMARY 
     A loudspeaker carrier is provided that comprises a layer of expandable material arranged on a surface to be mounted to a mounting site of a vehicle bodywork. 
     A loudspeaker assembly is provided that comprises a loudspeaker carrier, a mounting site on a vehicle bodywork and a layer of expandable material arranged between the loudspeaker carrier and the mounting site. 
     A loudspeaker assembly is provided that comprises a loudspeaker carrier, a mounting site on a vehicle bodywork, and foamed material arranged between the loudspeaker carrier and the mounting site and securing the loudspeaker carrier to the mounting site. 
     A method for mounting a loudspeaker carrier in a vehicle. The method includes providing a loudspeaker carrier and providing an expandable material. The method further includes arranging the expandable material between the loudspeaker carrier and a mounting site on bodywork of the vehicle and activating the expandable material such that the material expands, forming a foam structure, and causes the loudspeaker to be secured to the bodywork. 
     Other systems, methods, features and advantages will be, or will become, apparent to one with skill in the art upon examination of the following figures and detailed description. It is intended that all such additional systems, methods, features and advantages be included within this description, be within the scope of the invention, and be protected by the following claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The system may be better understood with reference to the following drawings and description. The components in the figures are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the invention. Moreover, in the figures, like referenced numerals designate corresponding parts throughout the different views. 
         FIG. 1  is a schematic diagram of a first exemplary loudspeaker assembly. 
         FIG. 2  is a schematic diagram of a loudspeaker carrier secured to vehicle bodywork. 
         FIG. 3  is a schematic diagram of a second exemplary loudspeaker assembly. 
         FIG. 4  is a schematic diagram of a third exemplary loudspeaker assembly. 
         FIG. 5  is a schematic diagram of a fourth exemplary loudspeaker assembly. 
     
    
    
     DETAILED DESCRIPTION 
     As required, detailed embodiments of the present invention are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the invention that may be embodied in various and alternative forms. The figures are not necessarily to scale; some features may be exaggerated or minimized to show details of particular components. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a representative basis for teaching one skilled in the art to variously employ the present invention. 
       FIG. 1  illustrates a first exemplary loudspeaker assembly  10  including a loudspeaker carrier  11 , a mounting site  12  on a portion of a vehicle bodywork  13  and a layer  14  of expandable material which is positioned on a surface  15  of the loudspeaker carrier  11  which is to be mounted on the mounting site  12  of the vehicle bodywork  13 . 
     In this example, the loudspeaker carrier  11  is a loudspeaker enclosure. However, the term loudspeaker carrier is used to denote any structure supporting directly or indirectly a loudspeaker diaphragm  16 . In this particular example, the loudspeaker diaphragm  16  faces away from the mounting site  12 . 
     The expandable material  14  has a composition such that it may be activated to cause the material to expand and, in particular, to form a foam structure with an increased volume. Upon activation, the expandable material  14  increases in volume to extend between the mounting surface  15  of the loudspeaker carrier  11  and the mounting site  12 . Additionally, upon activation, the expandable material  14  becomes tacky and acts as an adhesive so that the expanded material with the foam structure also provides an adhesive joint between the loudspeaker carrier  11  and the mounting site  12  so as to secure the loudspeaker carrier  11  to the vehicle bodywork  13 . The expandable material may be rubber-based or thermoplastic based and may be activated by subjecting it to a temperature above a predetermined threshold value, for example. 
       FIG. 2  illustrates the loudspeaker assembly  10  of the first exemplary embodiment after activation of the expandable material. The foam structure  17  is indicated schematically in  FIG. 2  by the closed pores  18 . However, the closed pores  18  are merely of an illustrative nature and are not intended to limit the structure of the expanded material to a foam structure with closed pores. The expanded material may also include a structure in which the foam includes interconnected cavities which extend from one side of the material to another. 
     An exemplary expandable material  14  may include an ionomer, a temperature activated foaming agent capable of increasing the volume of the material when it is subjected to an elevated temperature, and a tackifier for imparting tackiness to at least the outer surface of the expandable material when it is subjected to the elevated temperature. The ionomer may be an ethylene-α,β ethylenically unsaturated carboxylic acid, partially metallic ion neutralized copolymer ionomer. The relative proportions of the ionomer, temperature activated foaming agent and tackifier may be adjusted to provide the desired increase in volume, activation temperature and adhesion. Specific examples of compositions suitable for use as the expandable material are given in the examples disclosed in U.S. Pat. No. 5,266,133. 
     The volume increase of the expandable material  14  maybe 100% to 1200%. The volume increase may be selected by selecting the proportion of the temperature activated foaming agent included in the expandable material  14 . The expandable material  14  may be activated by subjecting the expandable material to an elevated temperature, for example 100° C. to 250° C. 
     In an exemplary method, the activation of the expandable material and the adhesion of the loudspeaker carrier  11  to the vehicle bodywork  13  is carried out during the so-called bake process or electrocoat bake process used in the priming and electrocoat process carried out on the vehicle bodywork. In the electrocoat process, the entire vehicle chassis is subjected to a bake process, for example at 180° C., to dry and cross-link the anticorrosion coatings, primer and paintwork applied to the chassis or vehicle bodywork. The loudspeaker carrier  11  is arranged on the mounting site  12  in the manufacturing line before the electrocoat bake process and subjected to the electrocoat bake process along with the vehicle bodywork. This exemplary method avoids the need for a further process to secure the loudspeaker carrier  11  to the vehicle bodywork  13 . 
     The expanded material having the foam structure  17  may also be used to seal the loudspeaker carrier  11  to the vehicle bodywork  13  and may also act as an acoustic baffle to improve the perceived sound quality of the loudspeaker. Since mechanical fixings such as screws and clips are no longer required to secure the loudspeaker carrier  11  to the vehicle bodywork  13 , any unwanted sources of noise such as rattles, which may occur at these mechanical fixings, can be avoided. 
     In examples in which the expandable material is not itself adhesive at the activation temperature, a further adhesive layer may be used to attach the expandable material  14  to the loudspeaker carrier  11  and the mounting site  12  of the vehicle bodywork  13 . 
     In the first exemplary loudspeaker assembly  10  illustrated in  FIGS. 1 and 2 , the mounting site  12  is planar and continuous. In the following exemplary loudspeaker assemblies, the expandable material  14  is used to mount a loudspeaker carrier  11  on non-planar surfaces. Like features are indicated with like reference numbers. 
       FIG. 3  illustrates a second exemplary loudspeaker assembly  20  which includes a loudspeaker carrier  11  which is to be mounted by a layer of expandable material  14  to vehicle bodywork  13 . In the second exemplary loudspeaker assembly  20 , the mounting site  12  of the vehicle bodywork includes two abutting portions  21 ,  22 , each with a chamfered edge  23  which produces a cavity  24  in the vehicle bodywork  13  at the mounting site  12  between the two abutting portions  21 ,  22 . Upon thermal activation of the expandable material  14 , the cavity  24  is filled, at least in part, by the increased volume of the expanded material which now has a foam structure. 
       FIG. 4  illustrates a third exemplary loudspeaker assembly  30  in which the loudspeaker carrier  11  is mounted on a mounting site  12  which has a step  31 .  FIG. 4  illustrates the loudspeaker assembly  10  after activation of the expandable material so that the loudspeaker carrier  11  is mounted via a foam material  17  to the mounting site  12  of the vehicle bodywork  13 . The increase in volume of the expandable material achieved by thermal activation can be used to compensate for the step structure of the mounting site  12 . The foam material  17  extends between the mounting surface  15  of the loudspeaker carrier  11  and the mounting site  12  of the vehicle bodywork  13 . The foam material is also adhesive and secures the loudspeaker carrier  11  to the vehicle bodywork  13  in addition to providing a seal around the loudspeaker carrier  11 . 
       FIG. 5  illustrates a fourth exemplary loudspeaker assembly  40  in which the loudspeaker carrier  11  is mounted on a mounting site  12  of the vehicle bodywork  13  by a layer of foamed material  17  which extends between the mounting surface  15  of the loudspeaker carrier  11  and the mounting site  12 . The mounting site  12  includes a welded overlapping joint  41  between two portions  42 ,  43  of the mounting site  12  which produces a step  44  in the mounting site  12  at the welded seam  45  between the two overlapping portions  42 ,  43 . 
     The foam material  17  is produced by activation of an expandable material. Upon activation, the expandable material is also tacky so that the expanded foam material secures the loudspeaker carrier  11  to the vehicle bodywork  13 . Due to the expansion of the expandable material, the step  44  and increased gap between the mounting surface  15  of the loudspeaker carrier  11  and mounting site  12  may be filled so that the foam material  17  extends between mounting surface  15  and the mounting site  12  of the vehicle bodywork  13 . The loudspeaker carrier  11  is planar despite the step  44  in the mounting site  12 . 
     The expandable material  14  may be applied to the loudspeaker carrier  11  or to the mounting site  12  of the vehicle bodywork  13 . The expandable material  14  may be attached to the loudspeaker carrier  11  by co-molding the expandable material with the loudspeaker carrier  11 , for example. The expandable material  14  may be attached by a further adhesive layer or by a mechanical fixing arrangement, for example by lugs or protrusions which protrude from either the loudspeaker carrier or the mounting site. 
     The use of a temperature activated expandable material and, for example, a temperature activated foamable material which also has an adhesive function enables the attachment and sealing of the loudspeaker carrier  11  to the vehicle bodywork  13  in a single step which can be carried out at the same time as the baking of the anticorrosion coating, primer and or paint of the vehicle bodywork. A typical baking process may be carried out at 160° for around 20 min, for example. 
     Since the loudspeaker carrier  11  need not be attached to the vehicle bodywork  13  by additional mechanical fixings such as screws, there are fewer restraints on the mechanical stability of the loudspeaker carrier itself. The sue of an expanded layer to provide both adhesion, sealing and acoustic baffling for the loudspeaker carrier may enable the width of the seal and/or the space required for the package as a whole to be reduced. Depending on the composition of the expandable material, the properties of the mounting site, for example roughness and cleanliness, required to achieve a reliable adhesive joint and seal may be less stringent. The expandable material may be used to compensate for variations in bodywork tournaments since the material can expand to fill any cavities, roughness, flange steps, small radii and tangential assembled bodywork. 
     While various embodiments of the invention have been described, it will be apparent to those of ordinary skill in the art that many more embodiments and implementations are possible within the scope of the invention. Accordingly, the invention is not to be restricted except in light of the attached claims and their equivalents.