Patent Publication Number: US-2016234602-A1

Title: Hydrophobic speaker systems

Description:
RELATED APPLICATIONS 
     This application claims the benefit of U.S. provisional patent application No. 62/112,939 filed Feb. 6, 2015 to the same inventor. 
    
    
     FIELD OF ART 
     The present invention relates to a loudspeaker system having dynamic and static parts to which water or condensation cannot adhere. In particular, the invention relates to parts of the system that are at least partially coated with a hydrophobic coating. 
     BACKGROUND OF THE INVENTION 
     “Amathophobia” is the fear of water or condensation. Hydrophobic coatings are coatings to which water or condensation does not adhere. Loudspeakers undesirably accumulate water or condensation that can degrade speaker performance and sound quality. For example, a foraminous speaker grill can become clogged with water or condensation which dampens the sound to the listener. For further example, water or condensation can accumulate on dynamic surfaces, such as the spider, the coil, the surround, or the diaphragm. Such accumulations can change the mass of the part to which the water or condensation attaches, thereby affecting system dynamics and degrading sound quality. For a further example, electrical contacts for the speaker inputs may be bridged by water or condensation, thereby affecting the circuit and degrading sound quality. For another example, the air gap of a loudspeaker may accumulate water or condensation, thereby changing the volume of the air gap and so the dynamics of the coil. 
     SUMMARY OF THE INVENTION 
     Briefly described, the invention includes a speaker system having at least one of internal and external static and dynamic constituent speaker parts at least partially coated with a hydrophobic coating to prevent water or condensation accumulations that would interfere with performance. Objects associated with the speaker, such as a speaker grill, power supply, speaker support, or speaker enclosure may also be at least partially coated with a hydrophobic coating to prevent water or condensation accumulations that would interfere with performance. 
    
    
     
       DESCRIPTION OF THE FIGURES OF THE DRAWINGS 
       The present invention will hereinafter be described in conjunction with the following drawing figures, wherein like numerals denote like elements, and 
         FIG. 1  is a plan view illustrating an exemplary embodiment of an exemplary speaker grill, according to a preferred embodiment of the present invention; 
         FIG. 2  is a front perspective view illustrating an exemplary embodiment of a detail of the speaker grill of  FIG. 1 , according to a preferred embodiment of the present invention; 
         FIG. 3  is a front perspective cutaway view illustrating an exemplary embodiment of the water or condensation free speaker system, according to a preferred embodiment of the present invention; 
         FIG. 4  is an exploded perspective view illustrating another exemplary embodiment of the water or condensation free speaker system, according to a preferred embodiment of the present invention; and 
         FIG. 5  is a front perspective view illustrating another exemplary embodiment of the water or condensation free speaker system, according to a preferred embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     As used and defined herein, “speaker” is means an audio loudspeaker. 
       FIG. 1  is a plan view illustrating an exemplary embodiment of an exemplary hydrophobic speaker grill  100 , according to a preferred embodiment of the present invention. Speaker grill  100  is a foraminous panel  102  having multiple foramina (holes)  104  for the passage of sound. Panel  102  has an hydrophobic coating  106  on both sides of speaker grill  102 . The coating may be, for non-limiting example, that described in US Published Patent Application US20060286305 A1 or equivalent commercially available hydrophobic (water or condensation-free) coating  106 . While panel  102  is illustrated as flat and rectangular, the invention is not so limited. In additional embodiments, panel  102  may be curved, multiply curved, or angled and may have a perimeter of any desired shape. The spacing, sizing, and shape parameters of foramina  104  are determined based on speaker dynamics (frequency range, power, etc.), and the foramina parameters must be adjusted to account for the hydrophobic coating  106 . The hydrophobic coating may also be amathophobic and/or oleophobic. 
       FIG. 2  is a front perspective view illustrating an exemplary embodiment of a detail of the speaker grill  100  of  FIG. 1 , according to a preferred embodiment of the present invention. The hydrophobic coating  106  is applied to the bore surfaces of the foramina  104  in addition to both sides of panel  102 . Accordingly, the sizes, shapes, and spacing of the foramina, when initially formed in panel  102 , must take into account the thickness of the hydrophobic coating  106  to be applied. For some hydrophobic coatings  106 , a layer is deposited and then reduced by wiping or use of a squeegee. For non-limiting example, for the inner walls of the foramina  104 , the same drilling jig and CAM program used to drill the holes  104  can be used to reduce the coating  106  within the foramina by using a smaller drill bit. 
       FIG. 3  is a front perspective cutaway view illustrating an exemplary embodiment of a hydrophobic speaker system  300 , according to a preferred embodiment of the present invention. Loudspeaker  300  includes a number of constituent parts including a diaphragm  302 , a surround  314 , and a basket  318  (illustrated by the rim of the basket). A diaphragm  302  sometimes includes a central cap which, for present purposes, will be regarded as part of the diaphragm  302 . With the top of diaphragm  302 , the top of surround  314 , and the top of basket  318  rim coated with hydrophobic coating  106 , the entire acoustic face of the speaker is made water. Such a speaker  300  may have both general application and also particular application in marine or rainforest environments. In particular embodiments, additional areas of hydrophobic coating  106  may be used on additional portions of the diaphragm  302 , surround  314 , and basket  318 , adaptive to anticipated use environments and speaker design. 
     Loudspeaker  300  also includes a former  314 , a coil  310 , and a spider  304 , all of which are internal dynamic constituent parts. Coating the interior of the former  314  with hydrophobic coating  106  reduces water or condensation accumulation between the former  314  and the central magnetic pole piece  312 , thereby assisting in keeping air gap  306  unobstructed. Coil  310  is wound on former  314  and also oscillates in air gap  306 , so a hydrophobic coating  106  on coil  310  will also assist in keeping air gap  306  unobstructed. Spider  304  preferably has hydrophobic coating  106  on both sides, as the spider  304  is a spring in a spring-mass-damper system and changes to its mass properties, as by water or condensation accumulation, can affect speaker  300  performance. 
     Loudspeaker  300  also includes magnetic materials as constituent parts, including magnet  322 , pole piece  312 , and air gap plate  316 . Pole piece  312  and air gap plate  316  conduct magnetic lines of force from magnet  322 . Hydrophobic coating  106  on portions of surfaces of magnetic materials that form the air gap  306  will assist in keeping the air gap  306  free of water or condensation. 
     Loudspeaker  300  also includes electrical contacts  308 , each of which is coated with hydrophobic coating  106  to prevent bridging of the contacts by water or condensation. For each of the external dynamic constituent parts (the diaphragm  302  and the surround  304 ) and the internal dynamic constituent parts (former  314 , coil  310 , and spider  304 ), the effect of the hydrophobic coating  106  on the acoustics of the speaker  300  must be determined and the design of the speaker  300  adapted to accommodate the effects. 
     The air gap  306  is preferably coated on all interior surfaces. The sizing of the elements making up the air gap must be adapted to ensure proper clearances after hydrophobic coating  106  is applied. The entire circumferential surface of the central magnetic pole piece  312  may be beneficially coated to prevent water or condensation accumulation between the pole piece  312  and the former  314  on which the coil  310  is wound. The electrical contacts  308  are coated peripherally to avoid interfering with electrical connections but preventing a water or condensation bridge from forming. The scope of the invention covers a loudspeaker with at least one hydrophobic coated constituent part as well as each hydrophobic coated part. 
       FIG. 4  is an exploded perspective view illustrating another exemplary embodiment of a hydrophobic speaker system  400 , according to a preferred embodiment of the present invention. Foraminous speaker grill  402  does not attach directly to speaker  404  but is coated as described in relation to  FIGS. 1 and 2 . Speaker  404  is coupled to speaker support panel  406  and grill  402  is fastened to speaker support panel  406 , which itself is fastened to speaker enclosure  408 . Speaker support panel  406  is exemplary of a wide variety of speaker supports that may benefit from an hydrophobic coating  106 . Speaker  404  may be speaker  300  with its hydrophobic coatings  106 . Power supply  410  is attached to speaker  404  via speaker support panel  406  and may also have an hydrophobic coating  106 , at least around its electrical contacts, to prevent water or condensation bridging. Ceiling speaker installations like hydroophobic speaker system  400  may be in place for decades, and water or condensation accumulations over such a time span can be large.  FIG. 4  illustrates that hydrophobic coated objects of the hydrophobic speaker system  400  do not have to be within, or be directly attached to, speaker  404 . 
       FIG. 5  is a front perspective view illustrating another exemplary embodiment of the hydrophobic speaker system  500 , according to a preferred embodiment of the present invention. Hydrophobic speaker system  500  is designed for marine environments and includes hydrophobic speaker  300  with at least the exterior surfaces of the surround  318  and diaphragm  302  coated with hydrophobic coating  106 , and with any exposed portion of the basket  320  also coated. Hydrophobic speaker system  500  also includes speaker enclosure  516 , speaker grill  504  and speaker support  508 . Preferably, speaker grill  504  is coated with hydrophobic coating  106 . Additional preferred portions for application of hydrophobic coating  106  includes seam  514  between upper  502  and lower  512  halves of speaker enclosure  516 , seam  506  between speaker grill  504  and upper  502  and lower  512  halves of speaker enclosure  516 . Seam  510  between upper half  502  of speaker enclosure  516  and speaker support  508  is not formed until installation, and so cannot be prepared with hydrophobic coating at the factory. As an example of a disfavored location for hydrophobic coating  106 , surface  518  is identified. Surface  518  receives and abuts crossbar  520 , causing compression of surface  518 . The combination of compression and vibration from sound or boat motion would destroy the hydrophobic coating  106 . 
     While applicant has provided exemplary embodiments, the invention is not so limited, but includes embodiments that apply to a wide variety of speaker designs, constituent parts, and associated objects.