Abstract:
A remote light source device for generating light which is transmitted to a light emitting device of an illumination system by a fiberoptic cable coupled between the light source device and the light emitting device. The light source device includes a light source and a cover or housing containing the light source, the cover or housing having a light orifice aligned with the light source. A fiberoptic cable coupler assembly is mounted to an exterior surface of the cover or housing adjacent the light orifice. The coupler assembly permits removable coupling of a fiberoptic cable to the device, the coupler assembly also being operative for aligning an end of the cable with the light orifice of the cover or housing so that light generated by the light source is received at the end of the cable for transmission thereby. Structures are provided for preventing the fiberoptic cable coupler assembly from becoming substantially heated by the light source.

Description:
FIELD OF THE INVENTION 
     This invention relates to illumination systems, and more particularly, to a remote light source device having improved heat management for use in such systems. 
     BACKGROUND OF THE INVENTION 
     Illumination systems, especially those which permit physicians and dentists to provide an area of high intensity illumination without the use of hands are important in treatment and examination of patients. Such an illumination system typically consists of a light emitting device, a remote light source device and a fiberoptic cable transmitting light generated by the remote light source device to the light emitting device. The remote light source device usually includes a light source consisting of a bulb as well as electronic controls and electrical connections contained in a housing. The housing includes a fiberoptic cable coupler which aligns one end of the fiberoptic cable with the bulb so that light produced thereby can enter and be transmitted by the cable. The light emitting device usually includes a headband assembly worn by the user, having a lens which projects the transmitted light exiting the other end of the fiberoptic cable in front of the user. 
     This type of remote light source device typically suffers from the principle disadvantage that the bulb contained therein generates a substantial quantity of heat. This heat necessitates more frequent replacement of the bulb and raises the exterior surfaces of the housing, including the fiberoptic cable coupler, to temperatures which can burn skin. 
     To reduce the problems associated with the heat generated by the bulb, conventional remote light source devices typically include a fan to remove heat generated inside the housing. Unfortunately, the cooling fan is only marginally successful in controlling the amount of generated heat within these devices, as the exterior surfaces and the fiberoptic cable couplers remain uncomfortably hot and difficult to handle. 
     Accordingly, there is a continuing need for a remote light source device with improved heat management. 
     SUMMARY OF THE INVENTION 
     A remote light source device for generating light which is transmitted to a light emitting device of an illumination system by a fiberoptic cable coupled between the light source device and the light emitting device. The light source device comprises light generating means and housing means containing the light generating means, the housing means having a light orifice aligned with the light generating means. Fiberoptic cable coupling means are mounted to an exterior surface of the housing means adjacent the light orifice. The coupling means permits removable coupling of a fiberoptic cable to the device, the coupling means also being operative for aligning an end of the cable with the light orifice of the housing means so that light generated by the light generating means is received at the end of the cable for transmission thereby. Heating preventing means are provided for preventing the fiberoptic cable coupling means from becoming substantially heated by the light generating means. 
     In another aspect of the invention, an illuminating system comprising a light emitting device and the remote light source device described immediately above. A fiber optic cable having a first end removably coupled to the light source device and at least a second end coupled to the light emitting device, is provided for transmitting light generated by the light source device to the light emitting device light. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The advantages, nature and various additional features of the invention will appear more fully upon consideration of the illustrative embodiments now to be described in detail in connection with the accompanying drawings wherein: 
     FIG. 1 is an exploded perspective view of a remote light source device according to an embodiment of the invention; 
     FIG. 2A is an exploded perspective view of the cover of the device; 
     FIG. 2B is a front elevational view of the cover of the device; 
     FIG. 3A is a front elevational view of the door of the device; 
     FIG. 3B is an exploded, partial sectional view through line  3 B— 3 B of the door of FIG. 3A; 
     FIG. 3C is an exploded, partial sectional view through line  3 C— 3 C of the door of FIG. 3A; 
     FIG. 4A is a front elevational view of the second heat shield of the device; 
     FIG. 4B is an enlarged end view of the channel of the second heat shield of FIG. 4A; 
     FIG. 5A is a sectional view of the chuck of the device; 
     FIG. 5B is an end view of the second end of the chuck of FIG. 5A; 
     FIG. 6A is a sectional view of the chuck cover of the device; 
     FIG. 6B is an end view of the second end of the chuck cover of FIG. 6A; 
     FIG. 7 is an electrical schematic depicting the electronic components of the device; 
     FIG. 8A is a partial sectional top view of the door and fiberoptic cable coupler of the device; 
     FIG. 8 b  is a sectional view through line  8 B— 8 B of FIG. 8A; and 
     FIG. 9 is a schematic view of an illuminating system employing the remote light source device of the invention. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     FIG. 1 shows a remote light source device  10  according to an embodiment of the invention. The light source device  10  generally comprises a chassis  12  stamped from sheet metal or aluminum, mounting and connecting various electronic components as will be described further on, a cover or housing  14  enclosing the components mounted on the chassis  12 , and a door  16  mounting a light source  70  (FIG.  3 C), hinged to the cover  14  and chassis  12 . 
     FIG. 2A shows the cover or housing  14  in greater detail. The cover or housing  14  is typically stamped from sheet metal or aluminum and has an open front end  15  and an open rear end  17  with a top wall  18  extending between a pair of side walls  20 . The top wall  18  includes an overhanging portion  19 , which in conjunction with a corresponding bottom wall portion  35  of the chassis  12  (FIG.  1 ), hinges the door  16  to the cover  14  and chassis  12 . The overhanging portion  19  includes a conventional spring loaded plunger latch  133  which cooperates with the door  16  to permit latching and unlatching thereof. Inwardly extending flanges  22  project from the bottom of the side walls  20 . The flanges  22  include apertures  24  for fastening the cover  14  to a bottom wall  109  of the chassis  12  with screw or like fasteners  26  that also attach support feet  32  to the bottom wall  109  thereof (FIG.  1 ). 
     Referring to FIGS. 2A and 2B, a heat shield  23  made of sheet metal, aluminum, or other suitable materials, and a carrying handle  31  made from plastic or other suitable materials, are respectively attached to the inner and outer surfaces of the cover top wall  18  by conventional screw or like fasteners  25  which pass through openings  34  in the top wall  18 . The heat shield  23  includes a horizontal wall  28  bridging a pair of downwardly extending vertical walls  29 . Spacers  30  are provided between the horizontal wall  28  of the heat shield  23  and the top wall  18  of the cover  14  to provide an insulating air-space  33  therebetween as shown in FIG.  2 B. The heat shield  23  advantageously shields the cover  14  from heat generated by the light source  70  mounted on the door  16 . 
     FIGS. 3A-3C collectively show the details of the door  16  of the device  10 . The door  16  is typically extruded from aluminum and includes a front side  36 , a rear side  37 , and a recessed center panel  38  which extends between first and second side panels  39   a ,  39   b  that curve back toward the rear side  37  of the door  16 . The recessed panel&#39;s  38  inner surface  53  includes two vertical L-shaped flanges  54  which extend between the door&#39;s  16  top and bottom edges  55 ,  56 . The recessed panel  38  further includes a coupler mounting area  40  which defines a circular light orifice  41 , and an air slot vent  42 . Fastener apertures  43  are provided between the ends of the air slot vent  42 . A fiberoptic cable coupler assembly  72  is mounted to the coupler mounting area  40  of the recessed panel  38  on the front side  36  of the door  16  with conventional screw or like fasteners  73  which extend through the apertures  43  in the recessed panel  38 . The coupler assembly  72  includes a chuck  74 , a chuck cover  75  and a thumb set screw  76  for locking a fiber optic cable (not shown) in the chuck  74 . Above the coupler mounting area  40  is an opening  44  which permits a control shaft  46  of a dimmer switch  45  mounted on the rear side  37  of the door  16  to extend therethrough. The dimmer switch  45  is retained to the inner surface  53  of the recessed panel  38  with conventional mounting hardware  47 . A control knob  48  is mounted on the free end of the dimmer switch shaft  46 . 
     Referring particularly to FIG. 3B, the inner surface of the first side panel  39   a  includes a hinge member  49  which allows the door  16  to be pivotally hinged to the cover  14  and the chassis  12 . This can be accomplished using a pin (not shown) installed through a first hinge aperture  21   a  defined in the overhanging portion  19  of the cover  14  and the top  21  of the hinge member  49  of the door  16 , and a screw (not shown) installed through a lower hinge aperture  21   b  defined in the extension portion  35  of the chassis  12  and the bottom of the hinge member  49 . The inner surface of the second side panel  39   b  includes a plunger receiving member  50  which cooperates with the plunger latch  133  of the cover  14  to latch and unlatch the door  16 . The outer surface of the second side panel  39   b  includes a stop member  51  which coacts with an adjacent side wall  20  of the cover  14  to prevent the door  16  from being pivoted into the interior of the device  10 . The rear edge of the second side panel  39   b  defines an L-shaped extension  52  that engages an electrical safety interlock switch mounted on the chassis  12  (not shown) that interrupts electrical power to all the components of the device  10  when the door  16  is opened. 
     Referring to FIG.  3 C and FIGS. 4A and 4B, the inner surface  53  of the recessed panel  38  mounts a second heat shield  57 . The second heat shield  57  is typically extruded from aluminum and includes a main plate  58  adjacent to a side plate  59 . The shield main plate  58  has an inner surface  60  which is made reflective (shiny) by plating and polishing. A lamp mounting bracket  61  extends perpendicularly away from the inner surface  60 . The shield main plate  58  also has an outer surface  62  which defines two channels  63 . Each channel  63  has an inner wall  64  that defines a channel locking projection  65 . The channels  63  slidably engage the L-shaped flanges  54  on the inner surface  53  of the recessed panel  38  to mount the second heat shield  57  on the rear side  37  of the door  16 . The outer surface  62  of shield main plate  58  further defines a light orifice  78  that axially aligns with the light orifice  41  of the recessed panel  38  of the door  16 , and an air slot vent  79 . The air slot vent  79  is typically aligned with the air slot vent  42  in the recessed panel  38  of the door  16 . A socket assembly  66  is attached to the bracket  61  of the heat shield  57  with conventional fasteners  67 . The socket assembly  66  mounts a light source  70  that generates high intensity light. The reflective inner surface  60  of the heat shield  57  causes some of the heat generated by the light source  70  to be reflected back toward the light source  70 . The light source  70  preferably comprises an extended life 24 volt EJL-5 bulb which operates at 24 or 25 volts. A standard 24 volt EJA bulb, which has a shorter life expectancy, can also be used if desired. The socket assembly  66  includes a pivoting lever  69  which helps disengage the light source  70  from a connector socket  68  of the assembly  66 . A thermostatic sensor  71  mounted to the shield side plate  59 , turns off the light source  70  if the temperature within the device  10  exceeds a predetermined threshold temperature (about 85° C.). 
     FIGS. 5A and 5B collectively show the details of the chuck  74 . The chuck  74  is typically manufactured from metal and includes a first end  81 , a second end  82 , and a cylindrical body  80 . A stepped axial bore  83  extends through the body  80  and defines a first diameter portion  84  sized for receiving an end of a fiberoptic cable (not shown), and a second larger diameter portion  85  having a diameter which typically corresponds to the diameter of the light orifice  41  in the recessed panel  38  of the door  16 . A threaded bore  86  extends orthogonally through the cylindrical body and communicates with first diameter portion  84 . The bore  86  threadedly receives the thumb set screw  76 . The stepped axial bore  83  at the first end  81  of the cylindrical body  80 , has a chamfered opening  84 . The second end  82  of the cylindrical body  80  includes an outwardly extending flange  87 . The flange  87  includes opposing mounting ears  88  with fastener apertures  89  which correspond with the fastener apertures  43  of the door recessed panel  38 . The mounting ears  88  and fastener apertures  89  permit the chuck  74  to be mounted to the door  16  as will be explained further on in greater detail. 
     FIGS. 6A and 6B collectively show the details of the chuck cover  75 . The chuck cover is typically manufactured from plastic and  75  includes a first end  90  and a second end  91 , a tubular wall  92  having an opening  93  and a thumb set screw aperture  94  extending perpendicularly through a section of the wall  92  into the opening  93 . The second end  91  of the tubular wall  92  includes a base  95  having an annular top wall  96  that extends outwardly from the tubular wall  92  and a skirt  97  depending from the periphery of the top wall  96 . A pair of webs  98  are formed on opposing sections of the top wall&#39;s  96  under surface  99  such that two C-shaped spaces  100  when open into the tubular wall opening  93  are formed between the skirt  97  and the webs  98 . The C-shaped spaces  100  approximately correspond in size and shape to the air slots  42  in the door recessed panel  38  (FIG. 3A) and communicate therewith as will be explained further on. The webs  98  include threaded apertures  101  which threadedly receive the coupler assembly fasteners  73  that extend through the apertures  43  of the door recessed panel  38  and the apertures  89  of the chuck  74 . 
     Referring again to FIG.  1  and also to FIG. 7, the chassis  12  and door  16  mount and connect various electronic components. These components include a power entry module  102  mounted on the chassis  12  which enables connection thereto of a conventional A/C plug and cord assembly  103  which is capable of carrying an A/C signal that powers the device. The power entry module  102  can include a conventional line filter  131  for filtering out noise in the A/C signal. A safety interlock switch  105  is electrically coupled between the power entry module  102  and the other electrical components of the device  10 . As explained earlier, the switch  105  interrupts electrical power to all the components of the device  10  when the door  16  is opened. The power entry module  102  applies the A/C signal (typically 230/115 volts) to a step down transformer  104  mounted on the chassis  12 . The transformer  104  steps down the voltage of the A/C signal (to about 24-25 volts) and applies it to the dimmer switch  45  and a full bridge rectifier  106 . The dimmer switch  45  selectively varies the current of the A/C signal applied to the bulb  70  thus, permitting the intensity of the light generated thereby to be selectively adjusted as desired. The bridge rectifier  106  mounted on the chassis  12  provides a rectified D/C voltage for powering an air intake D/C fan  107  and an air exhaust D/C fan  108 . The air intake fan  107  is mounted on the bottom wall  109  of the chassis  12  and is adapted to draw outside ambient air into the device  10 . The exhaust fan  108  is mounted on a rear wall  110  of the chassis  12  and is adapted to evacuate or exhaust air heated by operation of the light source  70  from the inside of the device  10 . The cooling provided by the fans  107 ,  108  desirably extending the service life of the device, especially the bulb light source  70 . The fans  107 ,  108  each include a thermistor (not shown) which automatically increases or decreases the speed of the fan with respectively increasing or decreasing temperatures. A perforated screen  132  made of sheet metal or the like, is mounted on the chassis  12  just behind the fan  107 , for blocking access to the transformer  104 , filter  130  etc. 
     FIG. 8A is a partial top sectional view through the door  16  of the device  10  showing an end  112  of a 2 or 3 mm fiberoptic cable  111  removably inserted in the fiberoptic cable coupler assembly  72 . The coupler assembly  72  removably couples the fiberoptic cable  111  to the device  10  and aligns the end  112  of the cable  111  with the door and shield light orifices  41 ,  78  so that light generated by the light source  70  is received at the end  112  of the cable  111  for transmission thereby. 
     FIG. 8B is a partial sectional view through line  8 B— 8 B of FIG. 8A showing an ambient air intake duct  130  which is defined in the fiberoptic cable coupler assembly  72 . In particular the duct  130  is defined between the cylindrical body  80  and flange  87  of the chuck  74  and the tubular wall  92  and base  95  of the chuck cover  75  of the fiberoptic cable coupler assembly  72 . The duct  130  communicates with the air slot vent  42  in the door recessed panel  38  via the C-shaped spaces  100  formed in the base  95  of the chuck cover  75 . The duct  130  and air slot vents  42  permit the exhaust fan  108  (FIG. 1) to draw ambient outside air into the coupler assembly  72 . The air drawn into the duct  130  passes across outer surface of the chuck  74  and draws away heat absorbed from light source  70  (FIG. 8A) by the chuck  74  during operation of the device  10 . This advantageously cools the fiberoptic cable coupler assembly  72  and permits safe handling of the coupler assembly  72  and the fiberoptic cable  111  during decoupling of the cable  111  from the device  10 . 
     FIG. 9 shows the remote light source device  10  of the invention as used in a typical illuminating system  120 . The system  120  includes a light emitting device  121  which is commonly used by physicians and dentists for providing an area of high intensity illumination that is controllable usually by head movement. The light emitting device  121  consists of a head light assembly  123  mounted on a head set  122 . A fiberoptic cable  124  has a first end  125  coupled to the fiberoptic coupler assembly  72  of the light source device  10  and second and third ends  126 ,  127  connected to the head light assembly  123  of the head set  122 . One of ordinary skill in the art will recognize that the remote light source device  10  of the invention can also be used in other types of illumination systems which employ fiberoptical cable coupled remote light source devices. 
     It should be understood that the embodiment of the invention described herein is merely exemplary, and that a person of ordinary skill in the art can make many variations and modifications to the described embodiment utilizing functionally equivalent elements to those described. For example, in other embodiments of the invention the coupler assembly can be mounted directly on the cover or housing instead of the door. In any case, such variations and modifications, including differing physical geometries, proportions, and materials are intended to be included within the scope of the invention as defined in the appended claims.