Abstract:
A phototherapy light device for directing light onto an infant. The phototherapy light device has a base containing an illumination source and a gooseneck type of elongated neck that extends outwardly from the base and has a distal end adapted to be positioned to direct the light onto the infant. An optical fiber transmits the light from the illumination source to the distal end through the optical fiber where the light is passed through a light emanating device located at the distal end of the elongated neck. The elongated neck has two flexible sections, one of which has two coaxial springs to provide flexibility in positioning as well as to impart sufficient strength and rigidity to the elongated neck. The dual spring concept provides a system having reduced stresses while creating a double fault structural system without compromising the flexibility of the elongated neck.

Description:
BACKGROUND 
     The present invention relates to a phototherapy light for treating infants and, more particularly, to a phototherapy light having an improved support system. 
     Hyperbilirubinemia is an affliction of newborn infants typified by an elevated level of a toxic molecule known as bilirubin in the infant&#39;s blood. Current medical therapy for such affliction is through the use of phototherapy where light radiation, generally within a certain wavelength band is directed upon the infant&#39;s skin. 
     There are a number of means or devices that are conventionally employed to direct the light upon the skin of the infant, one of which is to provide a bank of lights that are portable or can be built into an infant care apparatus and which direct the light radiation toward the infant positioned on an infant platform as a part of that apparatus. 
     Another means of providing phototherapy is through the use of a fiberoptic pad that is comprised of woven optical fibers such that the light radiation couples out of the optical fibers at the various bends that are formed in the optical fibers during the weaving process. 
     A still further means or device is by the use of a “gooseneck” phototherapy device that has a maneuverable, elongated neck that the caregiver can bend to the desired position to direct the light radiation upon the area of the infant where the light radiation is needed. 
     With the “gooseneck” type of phototherapy device, the distal end is positioned so as to direct the light radiation upon the infant and, in use, the distal end actually may be located over the infant in order to provide the needed light for phototherapy. As such, in that orientation the base is considerably remote from the distal end and yet the base supports that distal end and the elongated neck mounted therebetween in a cantilever manner extending outwardly from the base. The result is that the relatively high weight that is suspended over the infant requires substantial components of the phototherapy device to support the optical system adequately. 
     A difficulty, therefore, in the use of the gooseneck type of phototherapy light device, is that the flexibility and maneuverability of the distal end, as well as the elongated neck are important to facilitate the positioning of the distal, light emanating end at the desired location proximate to the infant and yet it is certainly important that the support for the distal end be sufficiently strong to guard against failure of the elongated neck that could result in the distal end sagging downwardly so as to potentially contact the infant. Since the light emanating, distal end can be at an elevated temperature, the contact with the infant is obviously not desirable and can cause harm to the infant. 
     At the present, there is provided a single pre-stressed helical spring that comprises a flexible section of the elongated neck in order to allow the user to position the distal end of the device at the desired location with respect to the infant. There are, however, certain difficulties with the use of a single helical spring. Among those difficulties are that the single spring has a high weight, is highly stressed and is a single fault system that upon failure, will inevitable result in the distal end dropping or sagging downwardly and thus having the potential of contacting the infant. The result is that the high stresses needed within the single internal support spring create low safety factors and single fault failure conditions in view of the relatively large mass suspended over the infant. 
     It would be advantageous to have a design and construction of a “gooseneck” type of phototherapy device that provides the necessary support for the distal end of the device but having reduced stresses and thereby increasing the safety factor so as to reduce the failure potential of the elongated neck and the potential downwardly movement of the distal end of the device. 
     SUMMARY OF THE INVENTION 
     Accordingly, the present invention relates to a phototherapy light device that is usable in the treatment of bilirubinemia of an infant. With the device of the present invention, the device preferably has a base that provides a foundation for the device. Extending from the base is an elongated “gooseneck” type of flexible neck that terminates at a distal end. Within the base, there is a light producing device, such as a light bulb, for the light therapy. The elongated neck encloses a light pipe or optical fiber system that transmits the light from the light source in the base to the distal end where a light emanating device is located to direct the light to impinge upon the infant. In an alternative embodiment, the light producing device may be located at the distal end of the elongated neck. 
     As used herein, the terms distal and proximal will be referred to in defining the location of the various components that are assembled to make up the present phototherapy light device of the present invention, that is, the proximal direction will be referred to as being toward the fixed base of the device while the distal direction will be referred to as toward the cantilever or light emanating end of the device. 
     By means of the flexibility of the elongated neck, the location of the distal end can be manipulated by the user to direct the light upon the desired area of the infant while the base remains in a stationary position. 
     The light emanating from the distal end of the optical fiber radiates somewhat outwardly in a diverging pattern by a lens where the light is directed outwardly from a housing to impinge upon the infant. The construction and operation of an embodiment of the lens and the overall assembly details of an exemplary distal end of the elongated neck is shown and described in co-pending U.S. patent application Ser. No. 11/327,554 entitled PHOTOTHERAPY LIGHT WITH FRESNEL LENS, filed Jan. 6, 2006 and owned by the present assignee and the disclosure of that pending patent application is hereby incorporated herein by reference in its entirety. 
     With the present invention, however, the elongated neck is specially constructed in order to sustain the weight of the distal end and extends from the base to the distal end of the phototherapy device. At least a portion of the elongated neck comprises a flexible section having an inner coil spring and an outer coil spring. The outer coil spring is an extension spring that is preloaded and encircles the inner coil spring such that the two springs are generally in a coaxial orientation. As such, the flexible section is strengthened by the presence of the two coaxial coil springs so that the elongated neck can fully support the distal end of the elongated neck and prevent the distal end of the elongated neck from sagging downwardly where it could contact an infant. 
     By the use of the coaxial dual springs, the outer spring can be only lightly pre-loaded as opposed to the prior art single spring that was heavily loaded. In addition, the employment of dual springs creates a double fault structural system which does not compromise the needed flexibility of the elongated neck, or ergonomics, and which allows the inner spring to support the distal end of the phototherapy device in combination with the outer spring. 
     In an exemplary embodiment, the elongated neck has a distal flexible section and a proximal flexible section. The proximal flexible section has the dual spring configuration while the distal flexible section may comprise only an inner spring. The proximal flexible section can be directly affixed to the base and there can be an intermediate tubing that is located between the proximal flexible section and the distal flexible section. A distal tubing thereupon extends for the distal flexible section to the distal end where the light emanating device is located. 
     As a further advantageous feature of the present invention, the coaxial spring arrangement is constructed by means of an outer spring assembly having end fittings and the outer spring assembly is dimensioned so as to be slidably affixed over the inner spring so that the outer spring assembly can be readily assembled to form the elongated neck and, just as easily, the outer spring assembly can be readily removed at the proximal end of the elongated neck for replacement thereof. As such in the event of a failure of either of the outer or inner springs, the other spring can be retained and only the failed spring replaced. 
     These and other features and advantages of the present invention will become more readily apparent during the following detailed description taken in conjunction with the drawings herein. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of a phototherapy light device constructed in accordance with the present invention; 
         FIG. 2  is a top view of an elongated neck constructed in accordance with the present invention; 
         FIG. 3  is a side view of the elongated neck of  FIG. 2 ; 
         FIGS. 4A ,  4 B and  4 C are cross sectional views illustrating certain areas of the elongated neck designated as  3 A,  3 B, and  3 C on  FIG. 3 ; 
         FIG. 5  is a side view of the of the elongated neck with the end fitting affixed thereto; 
         FIG. 6  is a cross sectional view of the end fitting shown in  FIG. 5  and taken along the line  6 - 6  of  FIG. 5 ; 
         FIG. 7  is a cross sectional view of the outer spring assembly of the present invention, 
         FIGS. 8 and 8A  are enlarged cross sectional views of the end fittings usable with the outer spring assembly of  FIG. 7 ; 
         FIG. 9  is a side view of the phototherapy light with the outer spring assembly installed; and 
         FIG. 10  is a cross-sectional view of the outer spring assembly taken along the line  10 - 10  of  FIG. 9 . 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring now to  FIG. 1 , there is shown a perspective view of the phototherapy light device  10  constructed in accordance with the present invention. As can be seen, the phototherapy light device  10  includes a base  12  and, in the embodiment shown, the base  12  can be mounted to a stand  14  so that the phototherapy light device  10  can be moved to a location proximate to an infant for use in administering phototherapy. As an alternative, the base  12  can be affixed to an infant care apparatus, such as an incubator or infant warmer or may be physically incorporated into an infant care apparatus. 
     There can be suitable controls on the base  12 , including a power switch  16  and an intensity control  18  to allow the user to set a desired intensity of the phototherapy light device directed onto an infant. In the upper surface of the base  12  there is an opening  20  where an elongated neck  22  is affixed to the base  12 . 
     The elongated neck  22  itself is manipulatable by a user such as typical of a gooseneck lamp so that the user can position the elongated neck  22  as desired in order to position the distal end  24  of the elongated neck  22  in a particular location to direct the phototherapy light at a selected area of the infant. Affixed to the distal end  24  of the elongated neck  22  is a shade assembly  26  that is generally conical shaped with a reduced diameter proximal end  28  and a larger diameter distal end  30 . 
     Thus, overall, there is an light source  32  located in the base  12  and which provides the light that is emitted from a light emanating device located at the distal end  30  of the shade assembly  26  to impinge upon the infant. As is conventional, the light source  32  can be a light bulb, for example, of about 50 watts, that provides light at the preferred wavelength to alleviate the bilirubinemia. 
     The elongated neck  22  is comprised of a number of components. As can be seen the proximal end  34  of the elongated neck  22  is affixed to the base  12  and there is a proximal flexible section  36  located at or adjacent to that proximal end  34  and the specific construction and assembly of that proximal flexible section  36  will be later explained. Extending distally from the proximal flexible section  36  is an intermediate tubing  38  that joins the proximal flexible section  36  to a distal flexible section  40 . Extending distally from the distal flexible section  40  is a curved distal tubing  42  that extends to the distal end  24  of the elongated neck  22  so as to be conveniently locatable at a desired orientation with respect to an infant. 
     Turning now to  FIG. 2 , there is shown a top view of the elongated neck  22  constructed in accordance with the present invention and, in particular, there can be seen, the proximal end  34 , the proximal flexible section  36 , the intermediate tubing  38 , the distal flexible section  40  and the curved distal tubing  42 . 
     Turning next to  FIG. 3 , taken along with  FIG. 2 , there can be seen a proximal inner spring  44  and a distal inner spring  46 . Both the proximal and distal inner springs  44 ,  46  are of the type used in gooseneck lamps, that is, the proximal and distal inner springs  44 ,  46  can be distended or bent and will remain at the distended position so that the elongated neck  22  can be manipulated to a desired position and remain at that orientation. As such the elongated neck  22  can be bent at both of the locations of the proximal and distal inner springs  44 ,  46  i.e. the proximal flexible section  36  and the distal flexible section  40 . 
     In  FIGS. 4A ,  46  and  4 C, there are cross sectional views taken at the locations indicated as  3 A,  3 B and  3 C of  FIG. 3  and illustrating the mounting of the proximal and distal inner springs  44 ,  46 . Thus, in  FIG. 4A , the distal end of the inner spring  44  can be seen fitting into an inner socket  48  formed in the proximal end of the intermediate tubing  38  and is preferable adhesively bonded thereto. In  FIG. 4B , there can be seen the proximal end of the distal inner spring  46  that is located within and preferably adhesively bonded to an inner socket  50  formed in the distal end of the intermediate tubing  38 . 
     Next, in  FIG. 4C , there is an illustration of the distal end of the distal inner spring  46  that is located within, and preferably adhesively bonded to an inner socket  52  formed at the proximal end of the distal tubing  42 . In summary, therefore, the intermediate tubing  38  spans between and is adhesively bonded to the distal end of the proximal inner spring  44  and the proximal end of the distal inner spring  46  wherein the distal end of the distal inner spring  46  is adhesively bonded to the proximal end of the distal tubing  42 . 
     Turning now to  FIG. 5 , there is shown a further side view of the elongated neck  22  having an inner fitting  54  that is used to connect the elongated neck  22  to the base  12  ( FIG. 1 ). In  FIG. 6 , taken along with  FIG. 5 , there is an enlarged cross sectional view of that inner fitting  54  and illustrating the proximal end  34  of the elongated neck  22  where there can be seen the optical fiber  56  that transmits the light from the light source  32  ( FIG. 1 ) to the optical fiber  56 , through the elongated neck  22  to the light emanating device located in the shade assembly  26  ( FIG. 1 ). 
     As such, in  FIG. 6 , the optical fiber  56  is shown located generally coaxially within the proximal inner spring  44 . Along the outer surface of the proximal inner spring  44  is a protective sleeve  58  that encloses and contains any debris that may be created by the flexure of the proximal inner spring  44  and to prevent that debris from migrating outwardly. The protective sleeve  58  is, in the illustrated embodiment, a heat shrink sleeve. There is also a foam washer  59  to prevent the debris from migrating axially away from the proximal inner spring  44  toward the inner fitting  54 . The proximal inner spring  44  can be adhesively affixed within the inner fitting  54 . 
     The inner fitting  54  has an inner cylindrical bore  60 , within which there is located a quartz member  62  having a proximal end  64  that receives the light from the light source  32  ( FIG. 1 ) and a distal end  66  that abuts against the proximal end of the optical fiber  56  to transmit that light to the optical fiber  56 . The proximal end of the optical fiber  56  is bonded to the inner cylindrical bore  60 , again preferably by means of an adhesive. The inner fitting  54  reduces in diameter towards the proximal end  34  of the elongated neck  22 , thereby forming a shoulder  68 , the purpose of which will be later explained. 
     Turning now to  FIG. 7 , there is shown a cross section view of an outer spring assembly  70  that is used to complete the elongated neck  22  by being located just external to and coaxial with the proximal inner spring  44  ( FIG. 6 ). The outer spring assembly  70  comprises an outer spring  72  having a proximal fitting  74  and a distal fitting  76 . Surrounding the exterior surface of the outer spring  72  is a cover sleeve  78  that provides a barrier to the migration of debris generated by the flexing of the outer spring  72  as well as to provide a good appearance to the overall device. The cover sleeve  78 , as will be seen, is normally adhesively adhered to the proximal and distal fittings  74 ,  76  as is the outer spring  72 . The outer spring is an extension spring that is preloaded so as to keep the elongated neck  22  in its position if there is some failure. The design of the outer spring  72  is dependent upon various factors, including the length of the spring, its internal stress level, the wire size, effect of corrosion, wear and the like. 
     Turning to  FIG. 8 , taken along with  FIG. 7 , there is a cross sectional view of the proximal fitting  74  and, as can be seen, the proximal fitting  74  includes a cylindrical proximal end  80  and a distally extending cylindrical flange  82 . The proximal end  80  is adapted to be plugged into the base  12  ( FIG. 1 ) and has a pair of O-rings  84  so as to fit with a close fitting within the base  12 . The proximal end of the outer spring  72  is affixed to the cylindrical flange  82 , preferable by an adhesive and the cover sleeve  78  is also affixed to the proximal fitting  74  at an outer flange  86  and, again, preferable by means of an adhesive. As a further feature of the proximal fitting  74 , there is a shoulder  88  formed that faces proximally and the purpose of which will be later explained. 
     Turning now to  FIG. 8A , taken along with  FIG. 7 , there is a cross sectional view of the distal fitting  76  and, with this distal fitting  76 , the outer spring  72  as well as the cover sleeve  78  are affixed, preferably by adhesive bonding, within an annular opening  90  formed in the distal fitting  76 . The distal fitting  76  also has an internal opening  92  formed therein having a predetermined internal diameter and the purpose of that internal opening  92  will be later explained. 
     Turning finally to  FIGS. 9 and 10 , there is shown, respectively, a side view and a side cross sectional view, taken along the line  10 - 10  of  FIG. 9 , of the outer spring assembly  70  in its assembled position to make up the elongated neck  22 . As can thus be seen, the outer spring assembly  70  has been slid over the proximal end  34  of the elongated neck  22  and is located at a position surrounding and general coaxial with the proximal inner spring  44 . As such, the proximal flexible section  36  has the advantage of having both the outer spring  72  and the proximal inner spring  44  acting together to prevent the distal end  24  of the elongated neck  22  ( FIG. 1 ) from sagging downwardly and also can provide protection against that sagging even in the event of a failure either the outer spring  72  or the proximal inner spring  44 . 
     In order to position the outer spring assembly  70  in the proper position, the outer spring assembly  70  is slid onto the proximal end  34  of the elongated neck  22  until the shoulder  88  of the outer spring assembly  70  abuts against the shoulder  68  of the inner fitting  54  so that the outer spring assembly  70  fits firmly against inner fitting  54 . At that point, the internal opening  92  of the distal fitting  76  has been dimensioned to slide tighty against the outer diameter of the intermediate tubing  38 . That slippage may be enhanced by the presence of some lubricious material i.e wrapped Teflon, intermediate distal fitting  76  of the outer spring assembly  70  and the outer surface of the intermediate tubing  38  as well as having a polished surface on that outer surface. 
     Accordingly, as can now be appreciated, the elongated neck  22  can be directed by the user to the desired area of the infant. By the particular arrangement of the proximal flexible section and the distal flexible section the phototherapy light device  10  can be manipulated as desired, however, with the proximal flexible section having an inner proximal spring and an outer spring proximate to each other and generally coaxial, there is a safety factor in the event of a failure of either of those springs to prevent the distal end of the light therapy device from sagging downwardly to contact the infant. 
     Those skilled in the art will readily recognize numerous adaptations and modifications which can be made to the phototherapy light device of the present invention which will result in an improved phototherapy system for an infant care apparatus, yet all of which will fall within the scope and spirit of the present invention as defined in the following claims. Accordingly, the invention is to be limited only by the following claims and their equivalents.