Patent Publication Number: US-6985313-B1

Title: Threaded lens coupling to LED apparatus with compressible locking ring

Description:
This application is a continuation-in-part application of Ser. No. 10/259,126, filed Sep. 27, 2002, now U.S. Pat. No. 6,785,053. 
    
    
     BACKGROUND OF THE INVENTION 
     This invention relates generally to generation and transmission of light, as from an LED source or sources; and more particularly concerns improvements in coupling devices enabling such transmission of light. 
     There is need for improvements in apparatus and methods to overcome deficiencies and problems with prior coupling system. 
     SUMMARY OF THE INVENTION 
     It is a major object to provide improved apparatus and methods as referred to. Basically, the invention provides an improved lens adapted for transmission of light comprising
         a) a lens body, defining an axis,   b) threading on the lens body extending about said axis, for reception in threading associated with the holder.       

     A further object is to provide threading on the lens body that includes multiple threads extending about said axis. Such threads are typically foreshortened to allow for tightening into the threading associated with the holder in less than about one full turn of the lens relative to the holder. 
     An additional object is to provide such threads on the lens body that extend only part way about the axis, as for example only about one-half way about the axis. Six such threads may advantageously be provided, to extend peripherally of the body, spiralling about the axis. 
     Yet another object is to provide a lens holder that extends only part way about said axis. As will be seen, the holder may extend about the lens threading, the holder threading having axial extent greater than the axial extent of such threading on the lens. 
     A yet additional object includes provision of threading associated with the holder includes multiple threads each having more than one full turn about the lens body, and the threading on the lens body includes multiple threads each having less than one full turn about said axis. 
     The threading associated with the holder advantageously including six threads each having about two full turns about the lens body, and the threading on the lens body includes six threads each having about one-half full turn about said axis. 
     A yet further object is to provide lens threads and connector mating threads or retaining ring threads configured to permit the mating parts to be push onto the lens and than with a half a turn to secure the two parts together. This feature prevents the wire leads of the connector from being twisted during installation. 
     An additional object is to provide thread pitch that allows for the connector or retaining ring and lens to be secured in only one full turn. In this regard connector and retaining ring may have six separate half threads with equally spaced wrap around the diameter. The lens mating six threads typically have two full turns which permits the units to be secured to varying thickness panels for example from a 32 nd  of an inch to ¼ th  inch thick. 
     Additionally, the mating lens and connector or retaining ring may be configured to be secured by hand tightening. If the connector or retaining ring are tightened past the secure point then the threads will slip back into a previous thread. This feature prevents the plastic threads of the lens, connector or retaining ring from being stripped. Also, when a rubber or metallic grommet is used between the panel and the connector or retaining ring, it functions as a locking unit. As the connector or retaining ring is tightened the grommet will compress. This compression causes backpressure on the threads of the mating parts providing a locking means. When a rubber seal is installed between the lens and the panel it prevents the entry of water and dust through the panel opening. 
     A further object is to provide a metallic locking ring that has teeth or projections to be axially compressible in bending mode. Certain teeth have ends that project in one axial direction to engage a mounting panel and other teeth have ends projecting in the opposite axial direction, to engage the end face of the holder. 
     An added object is to provide for leads of a 10 mm LED to be installed, using A and B entry ports, a terminal being located in each of the chambers beneath the entry ports completing the electrical connection. A four leaded flux LED can be accommodated using the four connector entry ports with their associated terminal contracts. The connector&#39;s four box terminals permit electricity to be introduced into three of the four LED leads while the fourth lead is common to all. The LED can then emit a full range of colors by electrically exciting various combinations of the LED leads. 
     Yet another object is to provide a method of extracting heat from the LED via connector terminals, which prevents over heating and extends the operating life of the device. As will be seen, the LEDs can provide a point source of light. The lens may have Fresnel rings, which disperses the LED point source of light and spreads it over the entire lens surface, providing a wide viewing angle. 
     These and other objects and advantages of the invention, as well as the details of an illustrative embodiment, will be more fully understood from the following specification and drawings, in which: 
    
    
     
       DRAWING DESCRIPTION 
         FIG. 1  is a side elevational view of the preferred form of threaded lens; 
         FIG. 2  is an end elevation taken on lines  2 — 2  of  FIG. 1 ; 
         FIG. 3  is a lengthwise section taken on lines  3 — 3  of  FIG. 2 ; 
         FIG. 4  is a right end elevation of a lens holder, defining a connector having six terminals; 
         FIG. 5  is a section taken on lines  5 — 5  of  FIG. 4 ; 
         FIG. 6  is a view like  FIG. 5 , but rotated 90° about an axis defined by the holder; 
         FIG. 7  is a left end elevation of the holder taken on lines  7 — 7  of  FIG. 6 ; 
         FIG. 8  is a section taken through an alternative lens holder in the form of an interiorly threaded retaining ring; 
         FIG. 9  is an end view of the  FIG. 8  ring, taken on lines  9 — 9  of  FIG. 8 ; 
         FIG. 10  is a side elevation taken on lines  10 — 10  of  FIG. 9 ; 
         FIG. 11  is a side view of a terminal plug with four pins useful to plug into four receptacle terminals as seen in  FIG. 4 ; 
         FIG. 12  is an enlarged view of a receptacle terminal; 
         FIG. 12   a  is an end view taken on lines  12   a — 12   a  of  FIG. 12 ; 
         FIG. 13  is an enlarged view of a receptacle terminal receiving endwise reception of a terminal pin; 
         FIG. 14  is a view like  FIG. 13  showing centering and interference connection of the pin to the terminal; 
         FIG. 14   a  is an end view taken on lines  14   a — 14   a  of  FIG. 14 ; 
         FIG. 15  is a side elevation showing a plug carrying an LED or LEDs, and having two terminal pins; 
         FIG. 15   a  is an end view taken on lines  15   a — 15   a  of  FIG. 15 ; 
         FIG. 16  is a top plan view showing another form of plug carrying an LED or LEDs, and having four terminal pins; 
         FIG. 16   a  is a side elevation taken on lines  16   a — 16   a  of  FIG. 16 ; 
         FIG. 16   b  is a side elevation taken on lines  16   b — 16   b  of  FIG. 16 ; 
         FIGS. 17–20  are enlarged fragmentary sections showing progressive connectors of an interiorly threaded retaining ring to an exteriorly threaded lens, in relation to a mounting panel; 
         FIG. 21  is axially exploded view of a threaded lens, threaded retainer ring and a locking ring also serves as a moisture seal, this being a preferred application of the threaded lens; 
         FIG. 22  is a view of the  FIG. 21  components, in axially assembled relation; 
         FIG. 23  is a view like  FIG. 22 , showing the locking ring and moisture seal component assembled in an alternate position; 
         FIG. 24  is an exploded view of a threaded lens, threaded holder with connector terminals, pin terminals; LED plug having four terminals, and locking ring and in relation to a mounting panel; 
         FIG. 25  is a section showing the assembled positioning of the lens, panel and locking ring of  FIG. 24 ; 
         FIG. 26  is a section showing the assembled positioning of the holder, LED plug, connector receptacle terminals, and supply power pin terminals; 
         FIG. 27  is an axially exploded view of a threaded lens, threaded holder with connector terminals; pin terminals, the LED plug having two terminals; and locking ring, in relation to a mounting panel; 
         FIG. 28  is a section showing assembled positioning of the holder, locking ring, LED plug, connector receptacle terminals and supply power pin terminals, of the  FIG. 27  components; and 
         FIG. 29  is like  FIG. 28 , but showing the locking ring in position forward of the mounting panel; 
         FIG. 30  is a view showing provision of a metallic locking ring, fitting on a lens body, between a panel and a holder being assembled onto the lens body; 
         FIG. 31  is an axial view of the metallic locking ring, on the lens body threading; and 
         FIG. 32  is an enlarged edge view of the locking ring showing ends of radially projecting teeth projecting at opposite sides of the ring, to be resiliently compressed upon make-up between the holder and panel seen in  FIG. 30 . 
     
    
    
     DETAILED DESCRIPTION 
     Referring first to  FIGS. 1–3 , a lens  10  is adapted to be secured to a holder, to be described, for transmission of light, as for example from an LED or LED array. The lens  10  has a body  10   a  defining a central axis  11 , and the body in shown as generally cylindrical defining an inner surface or bore  11   a , an outer surface  12 , and opposite ends  13  and  14 . End  14  is shown in the form of an integral cap having a dome  14   a , and an outwardly projecting annular flange  14   b . The inner side of the dome defines Fresnel rings  15 , for diffracting light rays impinging in direction  17  on the rings, diffused light exiting from the convex outer side  18  of the dome. The body may consist of molded plastic material. 
     Threading indicated at  19  is formed on the lens body extending about said axis, for reception in threading associated with the holder. Such threading spirals about axis  11 , while advancing in direction  17 , as shown. Typically, multiple such threads  19   a  are employed, and are alike. The threads are foreshortened in length to allow for tightening into mating internal threading associated with the holder, to be described, in less than one full rotary turn of the lens  10 , relative to the holder. Each thread  19   a  extends only part way about the axis  11  at the lens body periphery, and preferably six threads  19   a  are employed, each of which extends only about half way (180°) about axis  11 . 
       FIGS. 5 ,  6  and  24  show one form of lens holder  25 , which is also integral with a reduced diameter connector  25   a  at one end  26  of the holder. The opposite end  27  of the holder is centrally open at  27   a , for threaded reception of the lens body  10   a , as the holder is rotated. At that time, the lens is typically retained by or mounted to a panel  28 , as shown in  FIG. 25 , with a locking ring  29  mounted on the lens body and engaging wall  28   a  of the panel, and lens flange  14   b  engaging the opposite wall  28   b  of the panel. 
       FIGS. 17–20  and  21 – 23  also show provision of a modified lens holder in the form of a retaining ring  31 . That ring has internal threads at  32 , the same as the internal threads  30  the holder  25 . See also  FIGS. 8–10 . 
     Lens threads and connector mating threads  30  or retaining ring threads are formed to permit the mating parts to be pushed onto the lens and then with a half a turn, secure the two parts together. This feature prevents the wire leads protruding from the connector as at  85  from being twisted during installation. Additional turning of the connector during assembly would tend to cause excessive torque on the wires, which would cause an opposing twisting action on the connector. 
     The pitch of the threads allows for the connector or retaining ring and lens to be secured in only one full turn. The connector and retaining ring typically have six separate half threads, equally spaced wrap around the diameter. The lens mating six threads have two full turns which permits the units to be secured to varying panels from a 32 nd  of an inch to ¼ th  inch thick. 
     The mating lens and connector or retaining ring are configured to be secured by hand tightening. If the connector or retaining ring are tightened past the secure point, then the threads will slip back onto a previous thread, as by over-crest slippage seen in  FIGS. 19 and 20 . This feature prevents the plastic threads of the lens, connector or retaining ring from being stripped. 
     When a rubber grommet is used between the panel and the connector or retaining ring it functions as a locking unit. As the connector or retaining ring is tightened the grommet will compress. This compression causes backpressure on the threads of the mating parts providing a locking means. 
     When a rubber seal is installed between the lens and the panel it prevents the entry of water and dust through the panel opening. 
       FIGS. 17–20  show the thread interfitting sequence of the lens and holder elements, and the functioning of the compressible locking ring  29 , which may consist of elastomeric material, such as rubber. The locking ring may alternatively consist of axially compressible metallic material, to be resiliently compressed as the holder is tightened on the lens body, creating pressure and locking friction at thread to thread interengagement locations. The metallic ring may have the general configuration of ring  29 . 
     Note in  FIGS. 22 and 23  the reception of an LED plug type unit  34  into the interior  10   c  of the lens  10 , with the dome  34   a  of unit  34  proximate the Fresnel rings at the concave interior side of the lens cap end  14 . The leads  37  of the LED unit project from or through a circuit board  38  to which the leads are mounted, to support the unit  34 . A flange  34   b  on unit  34  is closely received in the bore of the lens, at location  40 , for centering. The lens has threaded attachment to the holder  31  as shown, and as described above. Holder ring  31  includes integral annular stiffeners  41  projecting outwardly. Ring  31  may consist of molded plastic material. 
       FIGS. 27 and 28  show the plug type LED unit  34  assembled to a connector  25   a  as described above, the internal threads of holder  25  assembled to the lens threads at  44 . The domed end  34   a  of unit  34  is received into the lens interior as described above; and locking ring  29  is held in compressed condition between the left end face of the holder and the panel  28 . The two pins or leads  37  of the LED unit are received into two parallel female terminals  46  received into and carried by slots  47  in the connector  25   a.    
       FIGS. 12–14  show progressive reception of a pin or lead  37  into a terminal  46 . The tapered end  37   a  of the pin or lead penetrates into the tubular body  50  of the terminal, and between tapered guide  51  and internal barb  52 . The guide and barb project laterally into the interior  50   a  of the body  50 , with the guide slidably guiding the pin, and the barb  52  having an edge  52   a  riding along the side of the pin, with friction, to center the pin in the interior  50   a . Edge  52   a  also gouges into the side of the pin to block endwise retraction or loosening of the pin from the terminal. Both  51  and  52  are resilient cantilever spring fingers. Wiring is retained to  46  at  46   a.    
     Another form of LED unit is seen at  60  in  FIGS. 11 ,  16 ,  16   a  and  16   b . Unit  60  has a polygonal body  61 , a domed end  62  from which light is emitted, and four pins  63  located at corners of a square. Those pins or leads are adapted to receive controlled electrical energization as from a circuit  64 , to control different colored light emission from three LEDs in the unit, the fourth pin being a common or ground. Color emission from unit  60  can thereby be controlled, by light color mixing within  60 , for emission from domed end  62 .  FIGS. 24 and 26  show pins or leads  63  endwise received within, and electrically connected, to four female terminals  65 . The latter are in turn received in four slots  66  in the connector  25   a . A control circuit appears at  64 , as in  FIG. 16 . See also  FIGS. 5 and 6 . 
     The connector  25   a  of  FIGS. 4–7  is configured to receive the pins of either type LED unit,  34  or  60 , i.e. it has four slots  66  at corners of a square, to receive the four terminals  65  of a unit  60 . It also has two slots  47  to receive terminals  46  of a unit  43 . Slots  47  are located within the square (see  FIG. 7 ) defined by slots  66 . A highly versatile and compact connector  25   a  is thereby provided. 
     The connector terminals also provide a method of extracting heat from the LED, which prevents over heating and extends the operating life of the device. 
       FIGS. 29 and 30  show use of a moisture sealing ring  29  located in a groove  29   a  in the lens body, adjacent the periphery of the lens  10 , to seal against the outer side of panel  28 . 
     In  FIG. 30 , a lock washer  75  fits over the lens threads  44  at the opposite side of panel  28 . The flat metallic washer has radially inwardly projecting teeth  76  which mesh with the threads  44  or thread grooves  44   a , as seen in  FIG. 31 . The radially inner ends  76   a  and  76   b  of alternate teeth also project away from the plane of the washer, at opposite axial sides thereof, to grip the panel  28  and the end face  25   c  of the holder  25 , as the assembly is made-up, thereby locking the assembly in made-up condition. See  FIG. 32 . The teeth  76  are axially resilient compressible, in bending mode, during make-up.