US1654350A - Block-letter sign - Google Patents

Description

Dec.. 27, 1927.

W. G. SHELTON BLOCK LETTER SIGN Filed Nov. 7, 1924 FLg. l

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INVFNTOR z By tlorlwys,

Dec. 27, 1927.

- 1,654,350 W. G. SHELTON BLOCK LETTER SIGN Filed NOV. '7, 1924 2 Sheets-Sheet 2 60 53 .56 .59 MWD/11 y lNvENTOR y;

Patented Dec. 27, 1927.

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WILLIAM GEN TRY SHELTON, F NEW YORK, N Y., AASSIGiNOIR T0 HALLIWELL-SHELTON ELECTRIC CORPORATION, OF NEW YORK, N. Y., A CORPORAZIJION" OF NEW YORK.

annex-LETTER sicav.V

application aiea November t, i924. serial No. 748,356.

This invention rela-testo improvements in illuminated signs of the block-letter type, and l,aims to provide improvements therein.

'lille present invention-provides a blockl letter sign, adapted for use as a unit of a composite illuminated sign, in which the brilliant lighting effect of gas-conducting tubes (Geissler tubes or the like) -may be had by the use of apparatus which, (while l@ making use of high voltages for producing a high potential difference on the4 electrodes of the tube or tubes) will not produce harmful or objectionable edects on the human system, .and which will not violate laws and lregulations generally established concerning 'ordinary lighting circuits (20-110-220 volts for example) and apparatus used therewith. f

- rllhe invention further provides a device 'in which the eliiciency is high, and a good lighting eli'ect obtained with an expenditure of a relatively small amount of energy, better illumination being obtained with small high frequency currents than can be obtained 25 with currents of lower frequencies, such as those of induction coils andy alternating current generators.

The 'invention further provides a blockletter sign having advantageous features as regards the use and manufacture thereof.

An embodiment of the invention is illus-i trated in the accompanying drawings, in which l Fig. 1 is a face view thereof.; Fig. 2`is a vertical section on line 2- 2,- Fig. 1; j

Fig. 3 -is a horizontal section on the line Fig( 4 is a front view with the face o cover of the sign removed; j

Fig. 5 is a .diagram of the electrical parts and connections.

Referring to said drawings, numeral 10 designates ayrareed gas-conducting illumi. nating tube (such as a Geissler tube) andl 15 a meansfor generating high frequency current for illuminating said tube, a sepa'- rate high frequency current generating means 15 being provided for each letter .(or, tube 10 in the shape of a letter), the current for each letter sign or tube thereby being small and notwithstanding the high voltages of such a generating means, having no objectionable or dangerous effect on the human system when a part thereof is brought into contact with the high voltage part of the device. These signs, similarly to the blockletter signs now in use having incandescent lamps, are used with others to form a composite sign, such as a wor-d or phrase. Current from an ordinary lighting circuit (110 `or 220 volts) for energizing the high frequency current generating means 15, is taken through suitable leads 17, 18, and as the current used is much less than that used for block-letter signs of the same size and lighting effect using filament lamps, and as the high frequency high voltage current is not dangerous, the letter sign does not violate civil regulations relating to ordinary lighting circuits and attachments thereto.

The block-letter sign preferably comprises a box or casing 20, in which the high-frequency current generating means 15 is housed. rlhe casing preferably has a cover 25 which closes the box or casing 20, and which also preferably serves for supporting the illuminating tube 10. For protecting the tube 10 and for. concentrating the light from said tube, a channel 27 is preferably formed on said cover 25'. This channel has vthe outline of a. letter of the alphabet corresponding to the shape of the illuminating tube 10, and is conveniently formed by a flange 28, standing up from the face of said cover. The cover yis preferably cut out at the bottom of said channel, as indicated at 29.4 A plate of insulating material 33 (such as sheet asbestos) is preferably arranged behind the face' of said cover 25 andthe illuminating tube 10 is conveniently fastened thereto, as by means of straps 35. The plate 33 is conveniently held between flanges 37, 38

on the box and cover, one ofowhich has a down turned portion 39 to close the `joint between said lianges. 'y

The tube 10 is bent to the shape of a letter ofthe alphabet, and as stated above, fits in the correspondingly shaped channel .27, and to the' end that an equal illumination of all parts of the letter may be obtained in a convenient manner, the tube is bent into a double outline of the letter. Thus'a continuous tube from end vto end, equally occupying all parts of the letter, and not crossing itself at any part, is attained. The tube consequently is able to lie flat against the late 33, or otherl party ofmthe cover, and Hence may be well protected when in a chanl nel such as 27 formed by the flanges 28. rll'he tube also occupies little space in a direction perpendicular to the face of the letter, in contrast to the space occupied by filament lamps. c

Any suitable high frequency current generating means 15 may be used. rlhe simple form here illustrated and adapted'for use with a lighting circuit having either alternating or direct current, comprisesfone or two transformers 40, 41, to the secondary or secondaries 43 of which a terminal 45, or the terminals 45, 46 of the illuminating tube l0 are connected (as by means of wires`48, Figs. 24). The primary or primaries 50 of the transformer 4() or transformers 40, 41 are in an oscillating circuit comprising a condenser 55, and spark-gap ,56 having terminals 58, 59. The condenser is charged through the spark-gap 56, as 58 is movable to make and break a circuit through lead 17, kick coil 60,

terminals 58, 59 (when in contact) conductor primaries) 50 of transformer 40, (or transformers 40,v 41) and' conductor 67 and branches 68, 69 thereof to the other lead 18 connected to the lighting circuit. This movable ,terminal 58 of-the spark gap is in the magnetic inliuence of the kick coil 60, and breaks the circuit at the spark gap 56 as soon as current begins tovflow in the circuit. The inductive kickof the coil 60 resulting from the breaking of the circuit, chargesthe condenser 55 with current at a relatively high voltage which when the sparking potential of the gap 56 is exceeded, results in a disruptive discharge across said spark gap 56, setting up high frequency oscillations from said condenser 55, through the primary (or primaries) 50 of the transformer 40 (or transformers 4'0, 41).` The secondary (or secondaries) 43 respond with (similar high frequency `currents which are forced to flow tlirougli tlie illuminating tube 10, and thereby villuminate the same. When the movable terminal 58 'of the spark gap, again makes contact with the terminal 59, a similar action to that just described takes place, and another V'chain of high frequency condenser oscillationsJ takes place.

The removable terminal 58 is conveniently normally pressed against the terminal 59 by. means of an adjustable weight 70 and a pivoted lever v72 having an arm 75 on whic the terminal 58 is carried. i v

Where two transformers 40, 41 are used they are connected so that current flows through the primaries thereof in opposite directions. It will be seen that the branch leads 17, 18 to a lighting cir-v cuit and in one of these leads a kick coil 60 is placed. One of the terminals of the heretofore explained the sign is safe to liandle, is simple iiiconstruction, may be economically manufactured, and is well adapted to stand the usage to which` these -signs are subjected.

.'lhe inventive ideas herein set forth may receive a variety of structural embodiments, and are not limited to the embodiment herein specifically shown and described. Y

What 1 -claimisz v 1. An illuminated letter unit of a composite illuminated sign, each unit comprising a casing, a channel in the lshape of a letter attached to said casing, an illuminating tube bent to the shape of a letter within said channel, means in said casing for generating a .high frequency current for illuminatingsaid tube, said high frequency current being of al kind which does not shock thehuman 'system,and leads to a-lighting circuit for supplying current to said high frequency current generator, said casing comprising a box and a cover, said box and cover con st ituting a weather-tight enclosure for said high frequency'generator, and said illuminating tube being mounted on said cover.

2. An illuminated letter unit of a composite illuminated sign, each unit comprising a casing, a channel in the shape of a letter attached to said casing, an illuminating tube bent to the shape of a letter within said channel, means in said casing for generating hanged box, and a lianged cover, said flanges over-lapping to exclude weather, and said -a high frequency ,current for illuminating lia box and cover constituting'a weather-tight enclosure for said high frequency generator,

and said illuminating tube being mountedv on said cover. c

3. An illuminated letter unit of'a composite illuminated sign, each unit comprising a casing, a channel in the shape of a letter attached to said casing, an illuminating tube bent to the shape of a letter within said channel, means in said -casing for generating a high frequency current for illuminating said tube, said high frequency current being of a kind which does not Shock the human system, and leads to a light-circuit for supplying current to said high frequency current generator, said casing l'comprsing a channeled part and a Hat plate beprising a flanged box and a tlan ed cover, hind said channeled part, adapted to be held said flanges over-lapping to exclu e Weather between said channeled part and box. l0 and said box and cover constituting a .ln Witness whereof, I have hereunto 5 Weather-tight enclosure for said high fre- Signed my name.` f

quency generator, and said illuminating tube v being mounted on said cover, said cover com- WLLIAM GENTRY SHELTON.

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