Abstract:
Plumbing fixtures are disclosed having acoustic electromagnetic transducers mounted thereon to transmit music or other vibrations to the fixture interior. The mounting assembly provides for a shield that reduces exposure of those in the fixture to a magnetic field generated by the transducers. In one form there is a post extending from the transducer, through the shield, to a bracket on the housing. Other structures are provided to facilitate removability of the shield and transducer for maintenance purposes.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     Not applicable. 
     STATEMENT OF FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
     Not applicable. 
     BACKGROUND OF THE INVENTION 
     The present invention relates to bath tubs, shower enclosures and the like which are provided with vibroacoustic transducers to project music and/or other sounds into the fixture. More particularly, it relates to an assembly for connecting such transducers while also magnetically shielding occupant&#39;s of the fixtures from magnetic fields generated by the transducers. 
     For experiential, therapeutic and other reasons it is desirable to project music, non-rhythmic sounds and/or other vibrations into bath tubs and other plumbing fixtures. However, it is desirable to place the vibration generation systems outside of the fixture to avoid contact between electrical devices and water, and to provide a cleaner and more elegant appearance. 
     One approach to achieve this is to place an electromagnetic transducer outside the fixture, against the fixture&#39;s exterior wall. See e.g. U.S. Pat. Nos. 3,585,991 and 6,523,191, DE 199,02,875 and EP 651987. 
     However, such transducers typically generate a magnetic field when operated in a manner that yields sufficient vibrations. The magnetic field produced by such a transducer may create interference with certain electronic devices used by a bather (such as a pacemaker or implantable defibrillator), or possibly certain electronic devices located in the bathroom near the fixture. 
     Resolving this concern can be problematic. For example, some proposed solutions to do so would interfere with the ability to remove and replace transducers from time to time during the life of the plumbing fixture. Other proposed solutions would interfere with the ability of the transducer to effectively transmit vibrations to and then through the tub wall. 
     As a result, a need exists for an improved transducer assembly that provides the desired vibrations to the plumbing fixture, but does not expose fixture occupants to undesirable magnetic fields. 
     SUMMARY OF THE INVENTION 
     In one aspect the present invention provides a plumbing fixture having mounted on an exterior wall thereof an electromagnetic transducer assembly. This assembly has a shield (a magnetic shield) mountable to the exterior wall (optionally removably mountable) and defining an internal cavity, a transducer having at least a portion thereof mounted in the cavity, and a means for transmitting vibrations from the transducer, past the shield, to the exterior wall. The shield can at least to some extent shield an internal portion of the plumbing fixture from magnetic fields generated by the transducer. 
     In one form there is a bracket positioned on an exterior wall of the plumbing fixture and sandwiched between that wall and the shield, such that the shield is removably mounted on the bracket. The shield and bracket can be removably linked to each other by a bayonet type connection and the bracket can optionally also be made from a magnetically shielding material. 
     A variety of means can be contemplated to transmit vibrations from the transducer, past the shield, to the bracket, and thus to the fixture. However, this needs to be done in a way that doesn&#39;t materially degrade the effectiveness of the magnetic shielding. Hence, it is proposed to create a small hole through a forward wall of the shield and pass a small diameter post through the wall. The post extends between the transducer and bracket and carries vibrations between them, past the shield. 
     In other forms a rearward portion of the post is threaded to an armature of the transducer, the shield is formed of steel, and the shield is essentially cup-shaped, with an open outward end. There can also be a shield cover configured to essentially enclose the transducer within the cavity. 
     A most preferred form of the invention is where the plumbing fixture is a bathtub or a shower enclosure, where the transducer is electronically controlled to deliver musical form vibrations. 
     It should be appreciated that the present invention provides a way of mounting a transducer to a plumbing fixture where the transducer can readily be removed for replacement or repair. For example, as will be understood from the following description, the transducer can simply be screwed on or off the post to mount it in place. 
     Further, an effective magnetic shielding is achieved without compromising maintenance access to the transducer, or the ability of the transducer to effectively carry music or other vibrations to the tub interior. 
     These and still other aspects of the present invention will be apparent from the detailed description and drawings. However, what follows are merely preferred example embodiments of the present invention. The claims should be referenced to assess the full scope of the invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of a bathtub embodying the present invention; 
         FIG. 2  is a bottom plan view thereof; 
         FIG. 3  is a detailed perspective view of a portion thereof on which a first transducer assembly of the present invention is mounted; 
         FIG. 4  is a partially exploded view of the device of  FIG. 3 ; 
         FIG. 5  is an exploded perspective view, taken more from the inward side, of the first transducer assembly of the present invention; 
         FIG. 6  is a view somewhat similar to that of  FIG. 3 , but of a second embodiment; 
         FIG. 7  is a partially exploded view thereof; 
         FIG. 8  is a view similar to that of  FIG. 5 , but of the second embodiment; 
         FIG. 9  is a cross sectional view taken along line  9 - 9  of  FIG. 3 ; and 
         FIG. 10  is a cross sectional view taken along line  10 - 10  of  FIG. 6 . 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     In  FIG. 1  there are shown multiple transducer shield assemblies  10  capable of shielding a bather  12  from magnetic fields generated by transducers  30  which transmit musical vibrations to the tub  14 . The tub  14  has a shell  16  which can be a fiberglass reinforced plastic or other conventional tub material. 
     The shell  16  includes a pair of side walls  18 , a head wall  20 , a foot wall  22 , and a bottom wall  24  which collectively define an internal portion of the tub in which water is conventionally placed. The head wall  20  may include a backrest portion  26 . 
     The transducers  30  are preferably electromagnetic. One particularly preferred transducer is the disk form Rolen-Star audio transducer. It receives an input signal via terminals  30   a ,  30   b  to produce a corresponding vibration that is transmitted to the tub. 
     While not shown, these terminals are connected to an electronic controller, which governs the electrical power according to the pattern of the desired vibrations and experience. For example, the controller could provide a power pattern consistent with musical vibrations, such that a consumer using the tub would be able to listen to music and receive a soft massage while bathing. 
     A first preferred transducer assembly is shown most clearly in  FIGS. 3 ,  4 ,  5 , and  9 . It has a cup-shaped shield  32  sized to at least partially house a transducer  30 . The shield  32  has an inwardly directed base  34  that defines an interior surface  36  and an exterior surface  38 . A shield rim  40  extends outward from the base  34 , away from the exterior surface  38  to define a cavity  42  that is preferably sized to house essentially the entire transducer  30 . 
     In this first embodiment the shield  32  can be secured directly to the shell  16  of the tub  14  via adhesive, caulk, epoxy, or any other method capable of withstanding the repetitive vibrations produced by the transducer  30 . The shield  32  is mounted such that the post  44  (in this case in the form of a bolt) is in direct contact with, for example, the side wall  18  of the tub  14  (shown in  FIG. 9 ). This allows for an efficient transfer of vibrations from outside of the shell  16  (from the transducer). 
     With specific reference to  FIGS. 5 and 9 , the base  34  includes an opening  46  through which a threaded shaft  48  of the bolt form post  44  extends until the head  50  of the post  44  abuts the exterior surface  38  of the base  34 . A fastener  52 , such as a threaded toothed hex nut, engages the shaft  48  of the bolt form post  44  to sandwich the base  34  of the shield  32  between the head  50  and the fastener  52 . 
     The post  44  threadably engages a mating threaded armature  54  of the transducer  30 . The armature  54  is actuated by the vibrations of the transducer and vibrates the coupled post  44 . 
     The shield  32  is preferably made of a magnetically shielding material. However, given that this is a water related environment which likely has great humidity, it is desirable to use a material which is also rust-resistant. Hence, rather than using just a cast iron shield, we prefer using galvanized steel having magnetic field attenuation properties of preferably greater than twenty-five to one. 
     Thus, provided a one-hundred and twenty-five Gauss input provided by the transducer  30  housed adjacent the interior surface  36 , the shield  32  material, thickness, and configuration is designed to attenuate the magnetic field adjacent the exterior surface  38  to no more than five Gauss, measured at a distance about one inch from the exterior surface  38 . 
     While the shield  32  of the first example embodiment does not fully encompass the transducer  30 , the shield  32  may be configured to more fully enclose the transducer  30 . For example, with reference to  FIG. 9 , a back plate cover  57  (shown in dashed lines in  FIG. 9 ) or a similar structure may be coupled to the rear of the shield  32  to enclose the transducer  30  within the cavity  42 . 
     If a cover is used, it is preferably attached via threads or another temporary means (rather than welding) so that the transducer can be accessed from time to time for maintenance. A wire port (not shown) is preferably included in the cover to allow the input wires to reach the terminals  30   a ,  30   b  if a cover is used. 
     Turning next to  FIGS. 6 ,  7 ,  8 , and  10 , the second mounting configuration may be used to mount a transducer  30 . This is especially useful when limited access to a mounting location is available, such as the situation where the transducers  30  are mounted under a ledge  59  of the tub  14  (shown in  FIG. 1 ). 
     Here, all the parts are essentially the same except for the addition of a shield plate and a bracket between the shield and tub, and associated linkages there between. The base  34  includes an anti-rotation structure in the form of a pair of slots  56  that engage a mating anti-rotation structure in the form of a pair of protrusions  58  formed in a shield plate  60 . The protrusions  58  of the shield plate  60  are configured to engage slots  56  of the shield  32  to prevent relative rotation between the shield plate  60  and the shield  32  during installation or removal of the shield  32  from the tub  14 . 
     The shield plate  60  also includes an opening  62  through which the threaded shaft  48  of the post  44  extends. The shaft  48  continues through the opening  46  in the base  34  where a fastener  52  engages the shaft  48  to effectively clamp the shield plate  60  and the shield  32  between the head  50  of the post  44  and the fastener  52 . As discussed above, the anti-rotation structures are aligned so that the protrusions  58  of the shield plate  60  extend into and are captured by the slots  56  formed in the shield  32 . 
     The disk shaped shield plate  60  is sized to essentially extend to the boundaries of the shield  32  and includes a central offset portion  61  that preferably abuts the exterior surface  38  of the shield  32 . The offset portion  61  helps accommodate an interlock in the form of a plurality of notched tabs  64  formed along the periphery  63  of the shield plate  60 . The tabs  64  include a notch  66  adjacent a resilient undulation  69 . The tabs  64  engage a mating interlock formed in a bracket  70  affixed to the tub  14 . 
     It should be appreciated that the shield  32  and shield plate  60  could instead be integrally formed as one piece. However, in this embodiment they are made in two pieces for ease of manufacture. 
     Turning next to  FIG. 7 , a bracket  70  is shown affixed to the side wall  18 . It is permanently secured to the enclosure with adhesive, caulk, epoxy, fiberglassing in, or by any other suitable method. Preferably, the bracket  70  is the same as the shield plate  60  such that the manufacturing process is simplified. The bracket  70  thus includes the tabs  64 , the notches  66 , and the offset portion  61 . The anti-rotation structure (e.g., protrusions  58 ) of the bracket  70  simply abuts the shell  16  to provide some clearance from the shell  16  of the tub  14 . 
     The shield  32  and coupled shield plate  60  are releasably interlocked to the bracket  70  by aligning the resilient tabs  68  of the shield plate  60  with the mating notches  66  in the bracket  70 . Relative rotation between the shield plate  60  and the bracket  70  forces the mating resilient tabs  68  of the respective shield plate  60  and bracket  70  to deflect and ride along the mating tab  68 . 
     The tabs  68  ride along each other into an undulation  69  that seats the tabs  68 . Rotation of the shield plate  60  in the opposite direction results in the tabs  68  disengaging and thus allowing the shield  32  to be removed from engagement with the tub  14 . Installation and removal of the shield  32  requires minimal lateral clearance around the shield  32  and transducer  30 . As a result, the shield  32  and coupled transducer  30  can be easily installed and removed from the tub  14  for service and repair. 
     Hence, they form a bayonet type of removable connection. The brackets can be attached at the factory, and the remainder of the assembly linked on-site to them. 
     With brief further reference to  FIG. 10 , the head  50  of the post  44  preferably is in contact with the adjacent bracket  70  to efficiently transmit the vibration of the transducer  30  to the shell  16 . 
     To provide additional attenuation of any magnetic field generated by the transducer  30 , both the shield plate  60  and the bracket  70  may be produced from a magnetically shielding material such as galvanized steel A568, or any other suitable material. 
     Preferred example embodiments of the present invention have been described in considerable detail. Many modifications and variations of the preferred example embodiment described will be apparent to a person of ordinary skill in the art. For example, the shield could be a square cup, with the transducer housing being rectangular rather than disk shaped. 
     Therefore, the invention should not be limited to the example embodiments described. Rather, the claims should be looked to in order to judge the full scope of the invention. 
     INDUSTRIAL APPLICABILITY 
     The invention provides an assembly for mounting a vibroacoustic transducer to a bathtub or the like, where the assembly transmits musical or other vibrations efficiently to the tub, while effectively shielding users of thereof from exposure to strong magnetic fields.