Description:
This invention relates to miniature incandescent lamp structures, and more particularly to devices of this type wherein the glass lamp envelope is carried on a base, both being receivable in a receptacle device carried in a panel in such a manner that the glass envelope is completely enclosed and hidden from view, and effects edge lighting of the panel.
Small lighting structures of the kind indicated above are used for instrument illumination, or illumination of indicia carried by or engraved in panels and the like. A prior miniature light structure employed a shallow cup-shaped receptacle having an annular sidewall which was internally threaded, and having an apertured bottom wall adapted to accommodate the tip portion of the glass envelope of a miniature electric lamp. The glass envelope was carried by a base assemblage comprising an externally threaded metal bushing which was adapted to be screwed into the receptacle cup, said bushing insulatedly mounting a metal contactor sleeve and the bushing and sleeve being respectively electrically connected to the leads from the lamp envelope. When the lamp assemblage was screwed into the receptacle, the external electrical connections for energizing the lamp were effected through the threaded bushing and the contactor sleeve.
While such prior miniature light structure functioned satisfactorily, it was subject to a number of drawbacks. For one thing, there was always the possibility that the lamp assemblage could work loose since it constituted a screw-threaded device which did not have any locking means to retain it against loosening. For another thing, the prior miniature light structure was constituted of a relatively large number of small parts the fabrication of which involved precise operations and represented an appreciable cost, resulting in an inordinately high price of the finished product. In addition, the screw-threaded construction required turning the lamp assemblage through more than one revolution in order to insert it in the receptacle or remove it from the same, and this was not only time-consuming but also involved the mating of fine screwthreads which conceivably could become damaged and stripped if not properly started.
SUMMARY
The above drawbacks and disadvantages of prior miniature light structures are obviated by the present invention, which has for one object the provision of an improved miniature incandescent lighting device which is constituted of relatively few parts that can be economically fabricated, thereby greatly reducing the cost of the final product.
In conjunction with this, another object of the invention is to provide an improved miniature incandescent light device as above characterized, wherein only a fraction of a complete turn of the lamp assemblage is required in order to insert and lock it into the receptacle, or to remove it from the same.
These objects are accomplished by the provision of a receptacle in the form of a shallow cup which has a pair of conductor bars each passing twice through the sidewall of the cup, said bars being disposed in spaced parallel relation with each other and constituting the contactor members of the receptacle. Received in the receptacle is a lamp assemblage comprising a miniature glass envelope with lead wires extending from it, and a base disk of insulating material having a flatted portion at one side and a recess therein which the lead wire end of the envelope is disposed. The flatted portion of the disk has oppositely disposed side recesses and contactor elements disposed in the same, said elements being respectively connected to the lead wires of the envelope. The lamp envelope and flatted portion of the base disk are receivable between the conductor bars of the receptacle, and when so inserted, the lamp assemblage can be given a quarter turn whereby the conductor bars will occupy the side recesses and engage the contactor elements located therein, thus completing the circuit through the lamp. When the conductor bars occupy the side recesses, the lamp assemblage is locked in the receptacle, and its removal involves merely a reverse turning through a quarter turn, to again free the base disk from the conductor bars.
Other features and advantages reside in the provision of an improved miniature incandescent lighting device as above characterized, wherein an effective wiping contact occurs between the conductor bars and the contactor elements, thereby tending to keep these clean and effective in their functioning; to provide an improved lighting device which is especially small and compact, and well adapted for disposition in a relatively thin panel for the purpose of edge lighting the same or lighting indicia which may be engraved in the panel; and the provision of a miniature lighting device in accordance with the foregoing, which will not readily work loose due to vibration or other disruptive forces, wherein replacement of the lamp assemblage can be easily and quickly effected, and wherein there is had great reliability, said device being not likely to fail or malfunction under adverse conditions of use.
Still other features and advantages will hereinafter appear. In the drawings illustrating several embodiments of the invention:
FIG. 1 is a top plan view of the miniature lighting device carried by a printed circuit board, a portion only of the latter being illustrated.
FIG. 2 is a transverse section taken on the line 2--2 of FIG. 1.
FIG. 3 is a transverse section taken on the line 3--3 of FIG. 1.
FIG. 4 is an exploded perspective view of the lighting device.
FIG. 5 is a transverse section of the receptacle portion of the lighting device, taken on the line 2--2 of FIG. 1.
FIG. 6 is an axial section of the lamp assemblage, taken on the line 6--6 of FIG. 4.
FIG. 7 is a bottom plan view of the lamp assemblage of FIG. 6.
FIG. 8 is a perspective view of one of the contactor elements employed in the lamp assemblage of FIGS. 6 and 7.
FIG. 9 is a top plan view of the insulating base disk of the lamp assemblage of FIG. 6.
FIG. 10 is an edge elevational view of the base disk of FIG. 9.
FIG. 11 is an edge elevational view of the base disk looking in a direction at right angles to that of FIG. 10.
FIG. 12 is a top plan view of an insulating base disk of a lamp assemblage illustrating a modification of the invention.
FIG. 13 is an edge elevational view of the base disk of FIG. 12.
FIG. 14 is an edge elevational view of the base disk of FIG. 12, looking in a direction at right angles to that of FIG. 13.
FIG. 15 is an axial sectional view of the receptacle portion of the lighting device incorporated in a panel and mounted on a printed circuit board.
FIG. 16 is an axial sectional view of the receptacle portion of the lighting device, imbedded in a panel and secured thereto.
FIG. 17 is a section through a multipiece receptacle device constituting another embodiment of the invention.
FIG. 18 is a front plan view of a receptacle mounted in a panel which has on it indicating reference marks for use when inserting or removing the lamp assemblage.
FIG. 19 is a view like that of FIG. 18 but showing the lamp assemblage inserted and locked in the receptacle.
FIG. 20 is a bottom plan view of a receptacle carried by a printed circuit board or panel, illustrating one possible arrangement of circuitry.
FIG. 21 is a view like that of FIG. 20, illustrating another arrangement of circuitry.
FIG. 22 is a top plan view of a miniature lighting device constituting another embodiment of the invention.
FIG. 23 is a perspective view of a lighting device of FIG. 22.
Referring first to FIGS. 1-5, the miniature lighting device comprises a receptacle part designated generally by the numeral 30, and a lamp assemblage designated generally by the numeral 32, said assemblage being insertable in the receptacle part and being locked therein when given a quarter turn after its insertion. The receptacle part 30 comprises a cup 34 of insulating material, said cup having an annular sidewall 36 and an apertured transverse end or bottom wall 38. Carried by the cup 34 are conductor bars 40 each passing twice through the sidewall of the cup, said bars being disposed in spaced parallel relation with each other and in a plane which is normal to the axis of the cup. The central portions of the bars 40 which are located within the cup are substantially of equal lengths, said portions being generally spaced apart a distance which is substantially equal to their lengths whereby there is defined a hypothetical square configuration if lines, such as the broken lines 42 in FIG. 1, are drawn between the corresponding ends of the enclosed bar portions.
The receptacle part 30 further comprises an annular internal shoulder 44 located in the lip of the cup 34, said shoulder being spaced axially outward of the bars 40 and being adapted for engagement with the lamp assemblage 32 to position the same with respect to the bars. The bottom wall 38 of the cup 34 has a central aperture 46 adapted to receive the rounded end or tip portion 48 of a small glass envelope 50 of an incandescent lamp proper making up part of the lamp assemblage 32. The receptacle 30 also carries a spiral coil spring 52 having its largest convolution 54 frictionally held in the aperture 46 against an annular shoulder 56 thereof. The small end or convolution 58 of the spring 52 is adapted for engagement with the rounded end 48 of the glass lamp envelope 50 as seen in FIGS. 2 and 3. Normally when the receptacle part 30 is free of the lamp assemblage as shown in FIG. 5, the spiral coil spring 52 is extended downward or within the cup 34, said spring extending in the reverse or upward direction when forced to do so by insertion of the lamp assemblage 32 as seen in FIGS. 2 and 3.
The lamp assemblage 32 comprises, in addition to the miniature glass envelope 50 of the lamp proper, lead wires 60 extending from the other end of the envelope, and a base disk 62 of insulating material, said disk having a flatted portion 64 at one side and also a central recess 66 therein, in which the said other end of the glass envelope is disposed. The flatted portion 64 has an end face opposite and parallel to the other side of the disk, and has oppositely disposed side recesses 68, and the assemblage includes contactor elements 70 (FIGS. 6 and 8) comprising stamped leaf spring which are disposed in the side recesses 68 and are electrically connected respectively to the lead wires 60. The contactor elements 70 comprise rectangular body portions 72 which are bent to have an angular shape, and comprise lanced central tongue portions 74 and also connector lug portions 76 of hooklike shape.
Referring to FIG. 9, the side recesses 68 of the disk 62 include supplemental arcuate portions in said flatted portion, and also supplemental arcuate portions 78 extending closely adjacent the bottom surface 80 of the disk. The disk 62 also has a diametric screwdriver slot 82 to admit a tool bit for the purpose of turning the lamp assemblage 32 for locking or unlocking it when it is carried in the receptacle part 30.
The connections between the lead wires 60 and the contactor elements 70 are preferably effected by soldering the lead wires to the connection lugs 76 of the elements in any suitable manner.
The lamp envelope 50 and flatted portion 64 of the base disk 62 are insertable in the receptacle part 30 between the conductor bars 40, and the receptacle shoulder 44 then becomes engaged with a corresponding shoulder surface 84 of the disk 62. This positions the side recesses 68 in registration with the conductor bars 40 whereupon turning of the base 62 will result in the conductor bars being accommodated in the recesses 68 and becoming engaged by the conductor elements 70. Thus, a circuit will be established between the conductor bars 40, contactor elements 70, lead wires 60 and filament 86 of the lamp envelope 50. In addition, the disposition of the conductor bars 40 in the side recesses 68 of the base disk 62 will lock the lamp assemblage in the receptacle part 30. The turning movement of the lamp assemblage to effect such connection and locking is 90°, this being illustrated in FIG. 19 wherein the assemblage has been turned clockwise through such arc from its initially inserted position.
In FIGS. 18 and 19 the letters "O" and "C" are carried by the panel in which the receptacle is mounted. The lamp assemblage 32 has an indicating mark 88 which is aligned with the letter "O" during insertion of the assemblage in the receptacle, and then becomes aligned with the letter "C" after the lamp assemblage has been given a quarter turn in a clockwise direction. Thus, an indication is had that the lamp assemblage is properly secured and locked in the receptacle, by observing the marking 88 and the letters "O" and "C."
The receptacle cup 34 may be of colored or clear plastic, and may constitute a filter element to provide coloring to the light from the lamp envelope 50 if this should be desired. Also, an opaque reflector disk 90 may be located adjacent the bottom wall 38 of the receptacle cup, to prevent light from the lamp from passing directly upward, and instead to distribute such light through the mounting panel material, as seen in FIG. 4.
When the lamp assemblage 32 is inserted in the receptacle part 30, the coil spring 52 will engage the lamp envelope 50 (specifically the rounded end or tip portion 38 thereof) and will bias the lamp assemblage outwardly of the receptacle part. Thus, when the lamp assemblage is turned 90° from the locked position illustrated in FIG. 19, the spring 52 will eject the lamp assemblage and facilitate its removal. While the base disk 62 is shown as having a flat bottom face 80, a similar base disk 62a having a rounded bottom face 82a may be utilized, such disk being illustrated in FIGS. 12, 13 and 14, with subscripts "a" after the numerals.
FIG. 15 illustrates the receptacle part 30 mounted on a printed circuit board 92. For this purpose, the conductor bars 40 may be slightly bent or offset, and then soldered to the copper surface of the board 92, to effect the lighting circuit. A panel 94 which is suitably recessed may then be secured over the receptacle part 30 and against the copper side of the printed circuit board 92, to provide a compact assembly having the advantages of printed circuitry. FIG. 16 shows the receptacle part 30 mounted in a recess of a panel 96 which has grooves 98 for accommodating conductors 100 which are secured to the conductor bars 40 of the receptacle.
FIG. 17 illustrates a two-piece receptacle cup, comprising an annulus 102 carrying conductor bars 40a, and a second annulus 104 of transparent or translucent plastic having light-filtering characteristics. The two annuli 102, 104 are secured together and constitute a unit which comprises the receptacle cup. This unit may be used instead of the one-piece receptacle cup illustrated.
FIGS. 18 and 19 show a panel 106 having indicia 108 comprising the letters "O" and "C," such letters constituting reference marks which in conjunction with the dot 88 of the lamp assemblage will indicate to the user the open and closed, unlocked or locked conditions of the assemblage.
FIGS. 20 and 21 illustrate printed circuit boards 110 and 112 respectively, having conductor elements 114 and 116 respectively of different configurations, secured to the conductor bars 40 of the receptacle part, said bars being suitably bent to accommodate said configuration.
Another embodiment of the invention is illustrated in FIGS. 22 and 23. This embodiment is similar to that of FIGS. 1-3 except that the cup part of the receptacle 30 has a fluted configuration providing a lens effect which modifies the light coming from the incandescent lamp. The cup 34b comprises a filter element, being constituted of colored plastic substance as mentioned in connection with the cup 34. The annular sidewall 36b of the cup 34b, being of light-conducting material which tends to reduce the intensity of light passing therethrough, is provided with a plurality of grooves 120 which have the effect of making portions of the wall 36b thinner in section, so as to form lens configurations. Where the thinner walls exist, they pass a more intense beam of light, as indicated by the arrows 122. Where the walls are thicker, the light is less intense, this being indicated by the arrows 124 and 126. The more intense light represented by arrows 122 has somewhat less coloring, as compared with the less intense light represented by the arrows 124 and 126. Use is made of this light pattern when mounting the receptacle part 30b, so that stronger light can be directed to more distant points or against surfaces which require more illumination. While six grooves 120 are illustrated, it will be understood that eight grooves or else a lesser number of grooves may be employed, and the grooves may be nonsymmetrically disposed to give various desired lighting effects or light patterns. A clear potting compound, such as clear plastic, may be utilized in mounting the receptacle part 30b in the supporting panel. This will not alter appreciably the modification of light as effected by the grooves 120. However, that part of the potting compound which occupies the grooves will be seen to have a convex curvature in the nature of a lens, which then will have the effect of intensifying and further modifying the light. In FIG. 22 one of the grooves 120 is illustrated as being occupied by clear potting compound 128, having such a lenslike configuration. It will be understood that other configurations of cup 36 are possible, to provide special lighting effects.
It will now be understood from the foregoing that I have provided a novel and improved miniature incandescent lighting device adapted for mounting in panels or on circuit boards or the like, for the purpose of providing illumination for instruments, edge lighting of panels, lighting of indicia engraved in panels, etc. The light device incorporates a lamp assemblage which is easily and quickly applied to and removed from a receptacle part by a quarter turn, as distinguished from multiturn threaded screw arrangements. The lamp assemblage is held against vibration by a coil spring which also functions to eject it when the assemblage is shifted to the unlocked position. Relatively few parts are involved, said parts being capable of economical fabrication and assembly. The electrical circuitry of the lighting device is simple and effective, resulting in great reliability. The lighting device is small and compact, and is foolproof and effective in its operation.
Variations and modifications are possible without departing from the spirit of the invention.