Lighted Display Units

Abstract

This invention relates to improvements in lighted display units of the kind in which individual characters are associated with one another to form a composite display. In the embodiment described, the unit is modularized in part with each module being specific to one character so that a composite display is formed by combining modules. There is provided, with respect to each character to be displayed, a front panel section including indicia portions which when lighted provide a representation of a selected character, a heat sink, and a lamp socket and socket holder assembly which is provided with lamp sockets oriented to underlie the individual segments of the character to be displayed. The heat sink and light shield unit is sandwiched between the front panel and the socket holder and is provided with individual bores of size to accommodate a single lamp bulb in alignment with the socket for that bulb and the indicia section to be lighted thereby.

Description

This invention relates to improvements in lighted display units and it relates particularly to units which display discrete characters as a combination of individual indicia segments in which characterization is altered by selective lighting of the individual indicia sections.

An object of the invention is to provide a display unit for instrument and computer panels, for control boards, checkout systems and a wide variety of other applications where illuminated digital displays are required. It is an object of the invention to provide a display unit: which can be produced in miniaturized form; which displays all characters, whether numerical or alphabetical or symbolical, in the same plane; which displays all characters with the same luminosity; whose light elements are conveniently replaced; and which can be manufactured readily at minimum cost.

Another object of the invention is to provide a display unit the elements of which are produced in a modular form permitting combination of characters in easily readable and recognizable form without undue spacing between adjacent characters. In this connection it is an object of the invention to provide a display unit module in which the characters are formed of individually lighted indicia segments permitting the representation of different characters by the illumination of selected segments and failure to illuminate others. Another object of the invention is to provide a display unit module which incorporates provision for representing a decimal point or degree mark without altering the pattern of spacing between adjacent characters.

These and other objects and advantages of the invention which will hereinafter appear are realized in part by the provision of an indicia panel formed with indicia sections capable of transmitting light transversely through said panel but being otherwise opaque there being seven light conducting sections each having the form of line segments, the line segments of three sections being arranged in spaced parallel relation to define the top, center, and lower horizontal portions respectively of a figure 8 and the other sections being arranged in pairs to define the sides at the upper and lower sections of the figure 8 by means associated with each indicia section respectively for directing light to the indicia section with which it is associated and to no other; and by means for energizing selectively the light source associated with each indicia section. Also, the advantages and objects of the invention are realized in part by the provision on the indicia panel formed with indicia sections capable of transmitting light transversely through the panel, but being otherwise opaque together with a lamp socket and a lamp socket holder assembly comprising a lamp socket holder and a plurality of lamp sockets mounted on one face thereof and disposed in positions corresponding to the position of the indicia sections of the panel; by the provision of a lamp shield and heat sink unit interposed between the indicia panel and the lamp socket holder flush against the face of the panel, the lamp shield being provided with a plurality of through openings one for each indicia section of the panel and underlying a respectively associated indicia section; and by the provision of lamps associated with the lamp sockets and disposed in respectively associated ones of the bores or through openings of the lamp shield.

A preferred form of the invention has been selected for illustration in the drawings. It is to be understood that various modifications may be made in the embodiment shown and that other embodiments are possible without departing from the spirit of the invention or the scope of the appended claims.

In the drawings:

FIG. 1 is an isometric view of a lighted display unit embodying the invention, comprising several display modules nested together in side-by-side relation with portions of the several modules shown fragmented or in section to illustrate details of their internal construction;

FIG. 2 is a view in front elevation of the panel of a lighted display unit embodying the invention;

FIG. 3 is a view in front elevation of a lamp shield and heat sink unit employed in the modules of FIG. 1;

FIG. 4 is a view in rear elevation of a fragment of the mounting plate of the display unit of FIG. 1 through the opening of which the rear face of a lamp shield and heat sink unit is visible;

FIG. 5 is a cross-sectional view taken lengthwise through the elements of one module of the unit taken on line 5-5 of FIG. 1;

FIG. 6 is a cross-sectional view of a fragment of a front panel and heat sink assembly taken on lines 6-6 of FIG. 5 and showing the light path by which a display indicia is illuminated by its respectively associated lamp;

FIG. 7 is a view in front elevation of the connector housing section of a display unit module.

Referring to FIG. 1 of the drawings, there is shown a lighted display unit generally designated 10 and consisting of a number of module elements, one set for each character to be displayed, which are mounted upon a common indicia panel and upon a common mounting plate.

In FIG. 1 the central portion of the indicia panel has been broken away but the left end and the right end of the panel are visible and they are designated by the reference numeral 12. Immediately behind the front panel 12 there is mounted a lamp shield and heat sink unit. One such heat sink unit is provided behind each character to be displayed on the front panel and it is one of the elements of the set of module elements associated with that character. In FIG. 1 the lamp shield and heat sink unit at the leftmost character is designated by the numeral 14. The next adjacent shield and heat sink unit is designated 16. Part of that unit has been broken away. The heat sink units of the intermediate module element sets have been omitted to make visible the structure that lies behind. However, a portion of the rightmost heat sink unit 18 is visible in FIG. 1.

The front and rear faces of the heat sink units are parallel and the rear face of the flat indicia panel 12 lies flat against the front faces of the several heat sink units. The rear faces of these heat sink units lie flat against the flat mounting plate 20 which lies immediately behind them. Immediately behind the mounting plate 20 there are mounted a number of lamp socket holder and lamp socket assembly units. One of these units is provided for each character to be displayed on the front panel. The leftmost assembly is designated by the reference numeral 22. Its forward and rear faces are parallel and it is mounted with its forward face flush against the rearward face of the mounting plate 20 so that it lies immediately behind the heat sink unit 14. The width and the height of the assembly 22 are the same as the width and the height of the sink unit 14. They need not be, and in fact are not, of equal length. The lamp socket holder and lamp socket assembly 24 is disposed adjacent the assembly 22 immediately behind the mounting plate 20 in alignment with the heat sink unit 16 of the second module set from the left in FIG. 1. Next to the right of assembly 24 is a similar assembly designated 26 which has been sectioned so the full length of several of its sockets (designated 28, 29 and 30), can be seen in assembled position. These sockets are adapted to receive the terminals of light bulbs or lamps three of which are visible in the second module from the left. These lamps, which are designated 32, 33 and 34, have their terminals inserted in the sockets which form a part of the socket holder and socket assembly 24. The lamps extend forwardly through an opening, a single opening 36 which accommodates all of them, into a respectively associated one of the bores which extend through the heat sink 16. The lamp socket holder and lamp socket assembly of the rightmost module is visible, although fragmented, in FIG. 1 where it is designated by the reference numeral 38.

The module associated with each character further comprises an output terminal assembly housing. Interconnection between the terminals of the several sockets of the socket assemblies through outlet terminals or leads is accomplished within the cavity of these output terminal housings. The leftmost terminal housing lies behind assembly 22 and is designated by the reference numeral 40 in FIG. 1. The housing associated with assembly 24 (which is connected to the rearward side of assembly 24) is designated 42 in FIG. 1. The housing behind assembly 26 is designated 44 and the adjacent housing, which is broken so that its interior is visible, is designated by the numeral 46. In the case of housing 46 the external circuitry comprises a ribbon 48 consisting of a series of insulated conductor wires arranged side by side and secured together to form a flat ribbon of conductors. A T-shaped block 50 has been molded over the ribbon of conductors. The block 50 fits within an opening at the rearward side of the housing 46 and is held in position within the cavity of the housing by the crossbar section of the T. Alternative constructions and connecting means are available for different applications. The arrangement in FIG. 1 is shown only schematically because the particular connection method forms no part of the instant invention. The connector housing of the rightmost module lies behind the lamp socket assembly 38 and is designated by the numeral 52. The output circuit construction at the rearward side of housing 42, 44 and 52 are similar to the construction, consisting of the ribbon 48 and block 50, at the rear output end of the terminal housing 46.

An additional section designated 54 is shown connected to the rearward side of the connector housing forward 40 of the leftmost module set. As will be explained below, and as illustrated in FIG. 1, certain of the characters to be displaced at the display panel are formed by illuminating selected ones of a number of line segments which, when all are lighted, form the figure 8. For example, in FIG. 1 at the right end of the display panel 12, the portion of the panel which is associated with the heat sink 18 is formed with seven line segments arranged in three rows at the left, center, and right of that section respectively. The center or second row comprises three line segments extending horizontally and arranged one above the other in parallel. These segments form the top 56, middle 58, and lower 60 portions of the figure 8. In the first row there are two line segments arranged in a line at the left of the segments 56, 58 and 60. Their direction is perpendicular to the three segments of the second row. The uppermost of these first row segments is numbered 62, extends from the upper segment 56 to the middle segment 58 of the second row. The lowermost segment 64 of the first row extends from the middle 58 to the lower segment 60 of the middle row. There are two segments in the third row; they are arranged in line at the right of the right ends of the three segments of the second row. The uppermost 66 of these two line segments extends from the upper horizontal bar or line segment 56 to the middle horizontal line segment 58 and the lower segment 68 of the third row extends from the end of the middle horizontal line segment 58 to the end at the right of the lower line segment 60. The bores or holes through the heat sink 18 are arranged one behind each one of these line segments and a lamp is contained in each of the bores. The line segment portions of the display panel are transparent and each will be illuminated and will transmit light when the lamp behind is illuminated. If all of the lamps behind the line segments 56, 58, 60, 62, 64, 66 and 68 are illuminated the numeral 8 will be clearly visible. If the lamp behind lamp segment 58, the center segment, is extinguished and the remaining line segments are illuminated then the character zero will be displayed. If the line segment 58 is illuminated along with line segments 62, 64, 66 and 68 and only line segments 56 and 60 are unilluminated, then the character displayed will be the letter H. In similar fashion, all of the numerals from 0--9 and many letters may be represented by illumination of some line segments and not illuminating others. The illumination or nonillumination of the several lamps may be controlled by electronic logic circuits. The unit 54 of the first module set, which additionally comprises the heat sink 14, the socket assembly 22, and the connector terminal housing 40, contains electronic logic circuitry by which selected ones of the lamps in heat sink 14 and socket assembly 22 are illuminated and extinguished upon the application of signals to the electrical input circuit ribbon 70 extending from the rearward end of the section 54.

A module is defined as the combination of the indicia panel section, the heat sink unit, the mounting plate section, the socket holder and socket assembly, the connector casing, and if there is one, the logic circuit housing all associated with a set of indicia for displaying one character. The heat sink units, the lamp socket holder and socket assemblies, the connector housing and the logic circuit housings all have the same height and same width and these units all have flat forward and rear faces so that these elements of a module set may be assembled end-to-end with one another and so that module sets may be assembled, side-to-side like building blocks to form larger assemblies as illustrated in FIG. 1 when more than one module set is employed. They are arranged side-by-side in which case the several indicia panel sections of the modules may be combined into a single unit. When there is more than one section their mounting plates are normally combined into a single mounting plate which may comprise the panel or subpanel of the instrument or control unit on which the display is to be mounted.

FIG. 2 is a front view a three module display unit in which the indicia panel section of the several units are not combined into a single panel. Instead only two, the panel associated with the center module and the panel associated with the rightmost module, are combined into a panel 72. The display panel of the leftmost unit is separate and individual to that unit. The indicia of each half of the panel 72 are divided into nine individual indicia sections. Seven of these indicia sections are arranged in a cluster which define a figure 8 as previously described. The eight indicia section 74 of the indicia panel section associated with the central module set represents a decimal point and is designated 74. The ninth indicia section of that same panel section is designated 76 and represents a degree mark. It will be apparent upon an examination of FIG. 2 that the cluster of line segments, which collectively are designated 78 in the drawing, associated with the rightmost module set of FIG. 2 are closely adjacent to the cluster of line segments, collectively designated 80 and associated with the central module set. The two characters are closely proximate to one another despite interposition between them of the decimal and degree marks.

This feature of the invention is provided by combining the light shield arrangement in which light from each lamp is applied to one indicia section and no other with a module construction in which the upper and lower sections of each segment of the module is offset laterally from the central portion which contains, or is aligned with, the cluster of seven line segment indicia sections.

This offset arrangement is apparent in FIG. 3 which is a view in front elevation of a light shield and heat sink unit. The unit selected for illustration in FIG. 3 is the heat sink unit 18 of FIG. 1. It is provided with seven bores arranged in a cluster in the central region of the unit. When assembled with the indicia panel 12, bore 81 underlies the line segment 56 and bores 82, 83, 84, 85, 86 and 87 underlie line segments 62, 58, 64, 60, 68 and 66 respectively. The upper section 88 and the lower section 90 of the heat sink unit 18 are offset laterally to the right relative to the central portion of the unit which contains the bores 82, 83, 84, 85, 86 and 87. Bore 92, at the lower right, and bore 94, at the upper right in FIG. 3, underlie the decimal point indicia segment 95 of FIG. 1 and the degree mark indicia section 96 of FIG. 1, respectively. These two bores, 92 and 94, extend into the upper and lower laterally displaces sections 90 and 88. It is apparent in FIG. 3 that the right face of the heat sink unit has a shape which is the inverse of the shape of the left face of the unit. The other sections of each module, specifically the socket holder and socket assembly and the connector housing, have their side faces similarly shaped so that adjacent modules may be nested one against the other to form a horizontal row of module sets as depicted in FIGS. 1 and 2. It is this arrangement that permits the cluster of indicia sections of one module to be placed closely adjacent the cluster of indicia modules of the adjacent module despite the interposition of the decimal point and degree symbol between them. That the elements of adjacent modules nest together is illustrated in FIG. 1 and by the dash lines of FIG. 2.

To illustrate that indicia panels having other than the seven bar cluster arrangement may be employed and in fact are compatible with such modules and that the invention is not limited to the specific indicia herein specifically described, the display unit of FIG. 2 includes, at the left, an indicia panel incorporating and alternative form of indicia, in this case the letters N and S.

Means are provided for fastening the indicia panel and the shield and heat sink unit to the mounting plate in a manner permitting their removal from the indicia plate side of that assembly. Any convenient means may be employed. In the preferred embodiment illustrated in the drawings, machine screws extend through openings in the indicia panel and the heat sink unit to threaded engagement with the mounting plate. Two such machine screws, identified by the reference numerals 97 and 99 are visible at the right end section of the indicia panel in FIG. 1. That holes are provided through the heat sink unit and in the mounting plate 20 to accommodate these machine screws is illustrated in the sectional view of heat sink unit 16 in FIG. 1 where the upper hole is designated by the reference numeral 100. The socket housing and socket assembly units and the connector casing units (and the logic circuit housings when used) are secured to the mounting plate in a way that permits their removal from the rear of the plate. Any convenient means may be employed. In the embodiment illustrated this means comprises a machine screw which is inserted from the rear end of the module forward through holes in the several elements of the module to threaded engagement with the mounting plate 20. This arrangement is illustrated in FIG. 5 which shows a cross-sectional view through one module taken on the plane of the rear mounting flat headed machine screws 101 and 102. These screws extend through the connector housing 52 and through the socket housing and socket assembly 38 into the mounting plate 20 where the end of the machine screws are threadably engaged. This arrangement of the fastening means permits removal of the indicia panel and heat sink units from the front of the assembly whereupon the lamps are easily accessible from the front of the unit.

The embodiment illustrated is designed for miniaturized production. In a typical production unit the height of the indicia panel is only 0.625 inches. It will be apparent that in a unit of that size the several lamp bulbs associated with each character are very small and are installed very close together. To facilitate their removal without the need for special tools, the opening in the mounting plate through which all of these light bulbs extend is made sufficiently large to accommodate all or most of the bulbs in a single opening. FIG. 4 is a view of the rear side of the mounting plate 20 which shows the outline of its opening 36 through which the rear face of the heat sink unit 16 is visible. Advantageously, as shown, the opening 36 is shaped to provide access to all of the bores or holes of the heat sink unit 16 which are intended or adapted to accommodate one of the lamps.

Returning to FIG. 5 of the drawings, several important features of the invention are illustrated. The section line is arranged so that the indicia sections 56, 58 and 60, and their underlying structures, are visible. The various elements of the module are assembled sandwich like so that the indicia panel 12 overlies the heat sink unit 18 which overlies the mounting plate 20. The socket assembly 38 is sandwiched between the mounting plate 20 and the connector housing 52. In the assembly 38, the lamp socket associated with the upper opening underlying the indicia portion 56 has been omitted to show that the socket housing is provided with a through bore to accommodate the socket. The bore 104 has uniform diameter throughout its length except that it has reduced diameter over a small portion 106 of its length close to its forward face. The effect of this reduction in diameter is to provide a shoulder 108 against which the socket structure may be seated. In this embodiment, the lamp socket is arranged to accommodate lamps whose external terminals comprise a pair of parallel wires extending rearwardly from the lamp base. The socket comprises two metal tubular sleeves, one for each lamp conductor wire, which are retained within an insulating sleeve which is generally cylindrical member which is provided with two, parallel, through openings along its length to accommodate the metal connector sleeves. The insulating cylinder is shown in assembled position within the socket housing opening which underlies the indicia portion 58. This insulating cylinder is designated by the numeral 110 and is shown to comprise two parallel openings 112 and 114. In the lowermost of the three openings of the socket assembly 38 (i.e., the opening behind the indicia section 60) the assembly is complete in that it includes the insulating sleeve 116 and two metal connector sleeves 118 and 120 inserted one in each of the two openings of the insulating sleeve. The two sleeves are lanced lengthwise in a forward section of their length and the lanced portion is bent inwardly to a position in which it has frictional engagement with the terminal wires of the lamp. In FIG. 5, the connector sleeve 20 has a lanced portion 122 which engages frictionally the terminal wire 124 of a lamp 126. The other terminal wire of the lamp has frictional engagement with a similar section of the connector sleeve 118.

The connector sleeves are sufficiently long so that they extend rearwardly from the socket housing and socket assembly unit 38 into the cavity of the connector housing 52. Means are provided for connecting these rearward ends of the connector sleeves to external circuit wires 126 which are held together in fixed position within the connector housing by a T-block 128. As previously explained, the showing of this connector arrangement is schematic and is intended to be representative of a variety of well-known constructional arrangements.

The construction of the connector housing 52 is shown in FIG. 7 which is an elevational view taken from the front. The sidewalls of the housing define a relatively large cavity in which the connection is accomplished. The opening 130 in the rear wall of the casing accommodates the T-block 128 or other constructional arrangement affording access to external circuitry.

The lamp cluster associated with indicia panels which include the seven line segment indicia section configuration, whether with or without additional indicia segments representing decimal and degree marks, produces a relatively large quantity of heat that must be dissipated efficiently to insure long life for the lamps. Further and as previously explained, there is a need to limit the application of light from each lamp to its respectively associated indicia portion and to no other. These two functions, heat removal and shielding, are accomplished primarily by the light shield and heat sink unit which comprises a block of heat-conductive material which is provided with a separate through bore to accommodate each lamp. The several bores through the unit have size permitting easy placement and removal of the unit over and from the cluster of lamps so that it presents no impediment to easy replacement of lamps.

The indicia panel also serves, by its construction, to aid in the dissipation of heat and to limit the flow of light from each bulb to its respectively associated indicia section. As best shown in FIGS. 5 and 6 the rear face of the indicia panel is recessed in regions underlying the several indicia sections and in an area overlying the bores or openings through the shield and heat sink units. This relationship is shown in perspective at the left front of the unit illustrated in FIG. 1. The recess behind the indicia section 60 is designated by the reference numeral 140 in FIGS. 5 and 6. Advantageously, as shown, the recess is circular and has the same diameter and is formed on the same axis as the lamp opening of the shield and heat sink unit which it overlies. The recess extends nearly through the front panel section so that the depth of the indicia section is relatively small. The indicia section comprises an opening through the indicia panel from its front face to the recess behind. The opening thus formed is filled with a light conducting material, of any desired color, and advantageously comprises a transparent or transluscent plastic material as shown. This construction, that is the provision of a recess, serves to elongate the opening in which the lamp bulb is housed and to limit the depth of the indicia openings. This construction permits the use of a thicker and therefore stronger indicia panel while providing maximum interior surface to absorb radiant energy or to reflect light rays to exit at the indicia opening. In addition this construction results in the flow of light from the lamp to the indicia opening both directly and after reflection so that the light impinges upon the rear face of the indicia opening from all directions permitting indicia openings with dimensions extending beyond the limits of the recess which it overlies. In FIG. 5 the line segments 60 is shown in transverse section to have a width very much smaller than the diameter of the recess 140. However, in FIG. 6 this line segment 60 is shown to have a length which exceeds in substantial degree the diameter of recess 140. Nonetheless it will be apparent that light rays emanating from lamp 26 and flowing directly or after reflection, will illuminate all portions of the front face of the line segment 60.

Claims

I claim:

1. In a lighted display unit in combination:

an indicia panel formed with indicia sections capable of transmitting light transversely through said panel but being otherwise opaque;

a lamp socket and a lamp socket holder assembly comprising a lamp socket holder having a plurality of lamp sockets mounted on one face thereof and disposed in positions corresponding to the position of the indicia sections of said indicia panel;

a lamp shield and heat sink unit interposed between said indicia panel and said lamp socket holder panel;

said lamp shield being provided with a plurality of through openings, one for each indicia section of said panel and underlying its respectively associated indicia section;

a plurality of lamps having electrical connections connected to a respectively associated one of said lamp sockets and disposed each in a respectively associated one of said through openings of said lamp shield; and

a mounting plate interposed between said lamp shield and said lamp socket holder, said mounting plate being provided with a through opening of size to accommodate all of said lamp and through which all of said lamps extend.

2. The invention defined in claim 1, including fastening means for securing said indicia panel and said lamp shield to one side of said mounting plate and removable from the panel side of the assembled combination of the panel, shield and plate, and means for securing said socket holder assembly to the other side of said mounting plate and removable from the socket holder side of said assembled combination of the holder and plate.

3. The invention defined in claim 1, in which said indicia sections are seven in number and have the shape of line segments arranged in a cluster defining, when said display unit is oriented vertically, the numeral 8; said lamp shield and socket holder assembly each comprising a central section aligned with the cluster and end sections offset laterally in the same direction from said central portion of said light shield and socket holder.

4. The invention defined in claim 3, in which said indicia panels comprise additional indicia sections overlying, in part, said laterally offset upper and lower sections of said lamp shield and socket holder and in which the upper and lower sections of the shield are formed with additional openings of size to accommodate lamps aligned with said additional sections and in which the socket holder includes lamp sockets aligned with said additional openings.

5. The invention defined in claim 4 in which said additional sections are generally circular and capable of representing degree and decimal mark; and in which the openings through said shield are circular.

6. In a lighted display unit in combination:

an indicia panel arranged for vertical mounting and comprising nine light conducting sections capable of transmitting light from the rear to the front face of said panel, said indicia sections being separated by opaque sections of the panel; seven indicia sections having the form of a line segment, the line segments of three of said seven sections being arranged in spaced parallel relation to define the top, center and lower horizontal portions respectively of a figure 8 and the other indicia sections of the seven sections being arranged in pairs to define the sides of the upper and lower sections of said figure 8;

two indicia sections of the nine sections being arranged at one side of said seven sections on a line parallel with said three of said seven sections and disposed adjacent the sections representing said top and lower horizontal portions of said FIG. 8;

lighting means associated with each of said indicia sections respectively for directing light to the indicia section with which it is associated and to no other upon the application of energy thereto; and

a housing containing said lighting means and having a central portion underlying said seven indicia sections and top and lower portions offset laterally from said center portion toward the side corresponding to said one side at which said two indicia sections are arranged relative to said seven indicia sections.

7. The invention defined in claim 6, said housing further comprising a lamp socket holder and lamp socket assembly unit including nine sockets adapted to receive terminals of a lamp and located, respectively, one behind each of said nine display sections;

said housing further comprising a separable output terminal assembly housing on one side of said socket holder and lamp socket assembly unit;

said sockets each having portions extending into said output terminal assembly and each comprising an insulating sleeve formed with two openings along its length and a metal connector sleeve lanced along a portion of its length and inserted into a respectively associated one of said two openings; and

said invention further comprising a mounting plate to which said indicia panel is secured at one side and to whose other side said lamp socket holder and lamp socket assembly is secured.