Abstract:
A dental handpiece may comprise a head portion and a swivel portion. The head portion may include a turbine and a light guide positioned to direct light out of the head portion near the turbine. The swivel may comprise a light emitting diode (LED) positioned to direct light into the light guide and a removable battery for powering the LED.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims the benefit of PCT Application No. PCT/US2016/019335, filed Feb. 24, 2016, which is a non-provisional of U.S. Provisional Patent Application No. 62/120,685 filed on Feb. 25, 2015, each of which is hereby incorporated by reference in its entirety. 
     
    
     TECHNICAL FIELD OF THE INVENTION 
       [0002]    The present invention relates to dental handpieces. More specifically, the invention relates to dental handpieces that include a light emitting diode. 
       SUMMARY OF THE INVENTION 
       [0003]    Dental handpieces may comprise a head portion and a swivel portion. The head portion may include a turbine and a light guide positioned to direct light out of the head portion near the turbine. The swivel may comprise a light emitting diode (LED) positioned to direct light into the light guide and a removable battery for powering the LED. 
         [0004]    Additional features and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by the practice of the invention. The features and advantages of the invention may be realized and obtained by means of the instruments and combinations particularly pointed out in the appended claims. These and other features of the present invention will become more fully apparent from the following description and appended claims, or may be learned by the practice of the invention as set forth hereinafter. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0005]    In order to describe the manner in which advantages and features of the invention can be obtained, a description of the invention will be rendered by reference to specific example embodiments thereof which are illustrated in the appended drawings. Understanding that these drawings depict only typical implementations of the invention and are not therefore to be considered to be limiting of its scope, the invention will be described and explained through the use of the accompanying drawings. 
           [0006]      FIG. 1  shows an exploded view of a dental handpiece according to an embodiment of the present invention. 
           [0007]      FIG. 2  shows a cross-sectional view of the dental handpiece of  FIG. 1 . 
       
    
    
     DETAILED DESCRIPTION 
       [0008]    An exploded view of a dental handpiece  10  according to an embodiment of the present invention is shown in  FIG. 1 . The dental handpiece  10  includes a head portion  12  and a swivel portion  14 . The head portion  12  may be attachable and detachable from the swivel portion  14  and may rotate freely relative to the swivel portion  14  when attached thereto. The swivel portion  14  may be configured to attach to a conventional air and water supply. 
         [0009]    The head portion  12  of the dental handpiece  10  may include a turbine  16  at one end and a light guide exit  18  may be positioned proximate to the turbine  16 , so that a work surface may be illuminated by light emitted from the light guide exit  18 . A main body  20  of the head portion may be made from a material that may withstand autoclaving, such as stainless steel, aluminum or a temperature resistant polymer such as polyether ether ketone (PEEK). 
         [0010]    The swivel portion  14  of the dental handpiece  10  may include a light emitting diode (LED)  22  at a first end positioned to direct light into a light guide  24  (see  FIG. 2 ) of the head portion  12  when coupled thereto. A second end of the swivel portion  14  may include a coupler  26  for attaching an air and water supply to the dental handpiece  10 . 
         [0011]    A cavity  28  formed in the swivel portion  14  may be sized and configured to receive a battery unit  30  therein. Located within the cavity  28  may be a plurality of electrical contacts  32  for electrically connecting with corresponding electrical contacts located on the battery unit  30 . Additionally, the cavity  28  may include apertures  34  for receiving corresponding protrusions on the battery unit  30 , which may facilitate the securing of the battery unit  30  to the swivel portion  14  of the dental handpiece  10 . 
         [0012]    As shown in  FIG. 2 , the battery unit  30  may include a rechargeable battery  36  therein, an activation switch  38  for activating the battery unit  30 . When the battery unit  30  is installed into the cavity  28  of the swivel portion  14 , a magnet  40  positioned in the swivel portion  14  may magnetically attract a metal plate  42  located within the battery unit  30  to maintain the battery unit  30  in the cavity  28  until sufficient force is applied to the battery unit  30  to overcome the magnetic force and remove the battery unit  30 . 
         [0013]    Control circuitry  44  may be located between the battery  36  and the LED  22 . The control circuitry  44  may be located within the battery unit  30 , may be located within the swivel portion  14 , or a portion may be located in the battery unit  30  and a portion may be located within the swivel portion  14 , as shown. 
         [0014]    The control circuitry  44  may include the actuation switch  38 , a timer, an accelerometer, a second switch, and a capacitor. When both the activation switch  38  and the second switch are closed, power will be directed to the capacitor and then to the LED  22 . The actuation switch  38  may be closed by an operator depressing a button  46  located on the battery unit  30 . The actuation switch  38  will remain closed for a specific time following the sensing of no motion from the accelerometer, after which the timer will cause the actuation switch to be opened. The second switch will be closed in response to motion sensed by the accelerometer, and will be opened if there is no motion sensed by the accelerometer. After the opening of the actuation switch  38  and/or the second switch, the LED  22  will no longer receive power from the batter, but will receive power from the capacitor for a moment until the capacitor is discharged. 
         [0015]    Accordingly, after an operator presses the button  46  to close the actuation switch  38 , the LED  22  will be powered and provide illumination while the operator is using the dental handpiece  10 . The LED  22  will automatically shut off, slowly fading due to the capacitor, after the handpiece  10  has been set down and remains unmoved for a period of time. 
         [0016]    As shown in  FIG. 2 , the LED  22  and an end of the light guide  24  proximate to the LED  22  may be positioned at the rotational axis of the head portion  12  relative to the swivel portion  14  of the handpiece  10 . This configuration allows the LED  22  to emit light into the light guide  24  no matter which rotational orientation the head portion  12  is relative to the swivel portion  14 . To facilitate the location of the LED  22  at the rotational axis, air that is directed through a channel  48  that is located at the rotational axis in the swivel portion  14  is directed radially outward through openings  50  at a location intermediate the LED  22  and the second end of the swivel portion  14  and into an annular cavity formed between the swivel portion  14  and the head portion  12 . From the annular cavity, the air is then directed to the turbine  16  through a channel in the head portion  12  that is located away from the rotational axis. 
         [0017]    The present invention may be embodied in other specific forms. The described implementations are to be considered in all respects only as illustrative and not restrictive. The scope of the invention is, therefore, indicated by the appended claims rather than by the foregoing description. All changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope.