Abstract:
Disclosed herein is a dental lamp socket assembly especially adapted for use with dental lamps. The dental lamp socket assembly is configured to dramatically increase the ease at which bulbs can be placed and/or replaced in and out of the socket assembly.

Description:
FIELD OF INVENTION 
     The inventions of the this application relate to the field of electric lamps for generating light for illuminating dental work areas, and in particular, to a socket assembly especially adapted for use in dental lamps. The socket assembly releasably holds a light bulb, such as a halogen bulb, and is constructed to enable the easy replacement of the bulb that minimizes manual handling of the bulb surface, and possible risk of damage to the bulb or even potential injury to personnel replacing the bulb. 
     BACKGROUND 
     Halogen bulb lamps are an efficient light source, and are prevalent in lamps used in many industries including the dental industry. A typical halogen lamp assembly includes two socket terminals that are spring loaded to engage, hold and provide electrical contact with the bulbs. These terminal connections must be compressed to create space for positioning the halogen bulb into the lamp socket terminal and then released when the bulb is in place. Due to the high intense heat and light radiation, it is important that the surface of the halogen bulb not be contaminated with oils and moisture from the hands of the operator during placement. The presence of such contaminants can result in premature bulb failure, or even worse, bulb rupture. In an effort to avoid this problem, measures have been devised to minimize transfer of undesired contaminants. For example, operators may wear gloves during the placement of bulbs. However, gloves also pass on certain undesired residues to the bulb surface, but cause the loss of tactile feel and control thereby making the installation process more difficult. 
     Another issue that is involved in replacing halogen bulbs involves the spring loading of the socket terminals themselves. Due to the nature of socket terminal construction, the opening of the light socket terminal is cumbersome, as it requires three separate but simultaneous motions: the compression of the first socket terminal, the compression of the second socket terminal, and the placement of a new halogen bulb. Inserting the halogen bulb is difficult for one person limited to accomplish these three motions. The level of difficulty is only increased when the additional factor of avoiding contact with the bulb surface is factored into the routine. Another factor adding to the difficulty is the implementation of the forceful springs integrated in the socket assembly which must be pushed against via the fingers of the operator while the movements are performed. 
     SUMMARY 
     The inventors have recognized the problems and difficulties of replacing halogen bulbs in dental lamp assemblies and have developed a new dental lamp having a socket assembly that increases the ease of bulb replacement. Accordingly, a first embodiment of the present inventions pertain to a dental lamp that includes a dental lamp socket assembly having a housing with a first socket terminal and a second socket terminal movably mounted on the housing. In a specific embodiment, the first and second socket terminals each are associated with a socket base member that interact such that each socket terminal is movable with respect to the socket base member between an extended position and a retracted position. A spring associated with the socket base member urges the socket terminal into its extended position. The first socket terminal and second socket terminal have associated therewith a first and second manually operated actuator, respectively. Force applied to the actuator is transferred to the associated socket terminal to push the socket terminal into its retracted position whereby space is created for entry and positioning of the lamp bulb into the socket assembly. Moreover, the lamp socket assembly includes a first catch member that is associated with the socket terminal housing such that it releasably holds the first manually operated actuator in a retracted position. In an alternative embodiment, the socket assembly includes a second catch member that releasably holds a second manually operated actuator in its retracted position. 
     In using a typical embodiment of inventions of this application, force is applied to the first manually operated actuator which moves the first socket terminal into retracted position. In the retracted position, the catch member is moved to hold the manually operated actuator. While the first socket terminal is held in the retracted position by the first catch member, the operator&#39;s use of both hands is enabled to retract the second socket terminal by depressing the second manually operated actuator, and inserting a lamp bulb into the lamp socket terminal while both the first and second socket terminals are held in their retracted positions: the first socket terminal by the first catch member and the second socket terminal by the operator&#39;s hand. Once the lamp is in place, the second socket terminal is allowed to move toward its extended position, and the first socket terminal is released by the catch member to allow movement toward its extended position. Accordingly, the socket assembly equipped with the catch member allows the easy stepwise opening of the dental lamp socket terminal that avoids the need to coordinate three movements simultaneously. It also assists in counteracting the force of the springs that are loaded in the socket base members, which can be relatively high and thus difficult to manipulate solely by hand. This arrangement facilitates the operator&#39;s use of a lamp bulb holder device that avoids direct manual contact of the bulb by the operator. 
     In another embodiment, the manually operated actuators are levers that pivot about axes on the base of the socket terminal housing. Also, according to this specific embodiment, the catch member relates to an pawl pivotably mounted to the socket terminal housing. When the first manually operated actuator (lever) moves the first socket terminal into its retracted position, the catch member (pawl) pivots to engage the lever so as to hold the lever, and in turn, the socket terminal in the retracted position. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  shows a top, perspective view of a dental lamp socket assembly. 
         FIG. 2  shows a side, perspective view of the dental lamp socket assembly shown in  FIG. 1 . 
         FIG. 3   a - c  are stepwise views of a dental lamp socket assembly in which a bulb is being replaced. 
         FIG. 4  shows the dental lamp socket assembly mounted to a dental lamp frame. 
     
    
    
     DETAILED DESCRIPTION 
     Turning to the drawings,  FIG. 1  shows a top perspective view of a dental lamp socket assembly embodiment  100 , that includes a housing  105  onto which a first and second socket terminal  110 ,  120  and corresponding socket base members  115 ,  125  are secured. First and second levers  130 ,  140  (constituting manually operated actuators) are secured to the lower portion of the housing  105 ′ via pivot pins  167 ,  169 . The first and second socket terminals  110 ,  120  movably mounted on socket base member  115 ,  125 , which are spring loaded to urge the socket terminals  110 ,  120  to extend out of the corresponding base member toward extended positions. Connectors  161 ,  162  for supplying electrical power to the lamp bulb is provided at opposing ends of the of the socket assembly  100 . First and second mounting screws  163 ,  164  associated with the lower portion of the housing  105 ′ attach the socket assembly  100  to a dental lamp frame (shown generally in  FIG. 4 ). Shield  180  is shown associated with the lower housing portion  105 ′. A pawl  135  is pivotably associated with a cross-frame member  171  of the housing  105  via pivot pin  191 . Socket base member  115  is also associated with the cross-frame member  171  at pivot pin  191 . Socket base member  125  is associated with cross-frame member  172  via connection  192 . 
       FIG. 2  shows a side, perspective view of the dental lamp socket assembly  100  with shield  180  removed.  FIG. 2  shows more clearly how the pawl  135  is pivotably associated to engage the first lever  130 . The pawl  135  includes a pawl base  212 , a pawl arm member  215 , and a tab member  220 . Depressing the tab  220  causes the pawl arm member  215  to pivot into the desired location for engaging the lever  130 . Also, shown is the pivot pin  167  that pivotably associates the lever  130  to the housing  105 . A spring  230  maintains contact of the lever  130  with the first socket terminal  110 . Also shown in  FIG. 2  is a hole  240  defined in the housing  105 ′ where screw  164  engages the housing  105 ′. 
     During placement of bulb as shown in  FIG. 3   a - c , the operator depresses the first lever  130 , which in turn pushes back socket terminal  110 .  FIG. 3   a  shows the direction the operator&#39;s hand  310  depresses the lever  130  (see arrow x), and the intended direction of the pawl (see arrow y) once the lever is in the proper place. As shown in  FIG. 3   b , once the lever  130  has moved back a sufficient distance, the pawl  135  has been pivoted such that the pawl arm member  215  holds the lever  130 , and in turn, the socket terminal  110  in a retracted position. With the socket terminal  110  held retracted, this frees both hands of the operator to depress the second lever  140  with one hand and manipulate the bulb  127  with the other hand, including via the use of a bulb holder device. Depressing the lever  140  causes the second socket terminal  120  to retract which then creates space for easy placement of the bulb  127 . As shown in  FIG. 3   c , once the bulb  127  is in place, the socket terminal  120  is allowed to return to its extended position by releasing force on the second lever  140 . Moreover, the pawl  135  is pivoted back thereby releasing lever  130 , and the first socket terminal  110  is allowed to move back toward its extended position, whereby both first and second socket terminals  110 ,  120  completely engage and hold the bulb  127  in spring biased contact at both opposing ends to provide electrical power. 
       FIG. 4  shows a rear side of a dental lamp  400  having a dental lamp frame  410 . A dental lamp socket assembly  100 , as described and shown in  FIG. 1  is shown attached to the dental lamp frame  410 . The dental lamp  400  also includes a reflector  420  that is pivotably engaged to the dental light frame  410 , that is shown swung open to allow access to the assembly  100 . Upon placement or replacement of the lamp bulb  127 , the reflector will be closed to allow normal operation of the dental lamp  400 . The bulb generates and directs light toward the reflector which will be reflected toward a shield  430   a - b , wherein light passes through the shield  430   a - b  and toward an intended dental work area. 
     It should be borne in mind that the housing can take a variety of shapes and configurations, and can incorporate multiple components. In typical embodiments of the present invention, the housing serves as a framework for securing the spring-loaded first and second socket terminals at an appropriate distance and location so as to receive a lamp bulb. 
     Although the foregoing description contains many specifics, these are not to be construed as limiting the scope of the present inventions, but merely as providing certain representative embodiments. Similarly, other embodiments of the inventions can be devised which do not depart from the spirit or scope of the present inventions. The scope of the inventions is, therefore, indicated and limited only by the respective appended claims and their legal equivalents, rather than by the foregoing description. All additions, deletions, and modifications to the inventions, as disclosed herein, which fall within the meaning and scope of the claims, are encompassed by the present inventions. The disclosures of any references cited herein are incorporated in their entirety to the extent not inconsistent with the teachings herein.