US 2779057 A
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Jan. 29, 1957 Filed Feb. 26, 1952 H. J. GRAHAM ETAL 2,779,057
APPARATUS FOR MAKING VEHICLE DESTINATION SIGNS s Shets-Sheet 1 INVENTORS.
HER-BERT .yeammm oorm E- oReFm W\LL\AN F.RE\$,\6ER ANDREW J. SHHBHCF Jan. 29, 1957 H. J. GRAHAM ETAL 2,779,057
APPARATUS FOR MAKING VEHICLE DESTINATION SIGNS Filed Feb. 26, 1952 3 Sheets-Sheet 2 H TTORIUE Y Jan. 29, 1957 H. J. GRAHAM ETAL 2,779,057
APPARATUS FOR MAKING VEHICLE DESTINATION SIGNS s Sheets-Sheet 5 Filed Feb. 26, 1952 I INVENTORS.
: ATTORNEY United States Patent APPARATUS FOR MAKING VEHICLE DESTINATION SIGNS Herbert J. Graham, Abington, and John E. Orban, Philadelphia, Pa., and William F. Reisiger, Flushing, N. Y., and Andrew J. Shahack, Philadelphia, Pa, assignors to Electric Service Manufacturing Company, Philadelphia, Pa., a corporation of Pennsylvania Application February 26, 1952, Serial No. 273,522
3 Claims. (Cl. 18--17) The present invention relates generally to apparatus for molding plaques relieved for use in the art of printing and is more particularly concerned with a construction adapted for use in molding such plaques by an improved method, the plaques thus produced affording an improved method for producing a printed curtain.
In making printed curtains, for example, of the type used in vehicle destination sign mechanisms, it is conventional to start out with curtain material which is translucent and to print thereon a field of contrasting color forming characters in the color of the curtain material desginating the destination. The characters are each suitably hollow relieved in an individual plaque, and these plaques are assembled in side abutting relation to one another for forming the sign on the finish-ed curtain, and are further assembled so that the upper and lower edges thereof abut respectively the plaques for the next preceding and the next following signs. All the plaques for the signs to be printed are then inked and applied to the curtain.
This conventional way of making printed curtains utilizing individual letter or name plaques affords a field which is not uniform and solid because lines extending lengthwise of the curtain are formed between individual letters or names where the printing plaques are arranged along a single line in side edge abutting relation, while other lines extending transversely of the curtain are formed between the several lines of printed matter where a plurality of plaques are arranged in multiple line relation. In order to obtain a uniform, solid field these lines are brushed out or otherwise obliterated.
The plaques conventionally employed for printing curtains and the like may be assembled to form a destination sign, used, and then stored in their assembled condition until needed again, or, after being used, they may be disassembled and utilized in forming other destination signs as need arises. Either procedure may make it necessary to provide considerable storage space for the plaques and to maintain a comparatively large investment therein because the opportunities for reuse of the plaques are limited, particularly when they are prepared as plaques for printing a complete name instead of only a letter of the alphabet.
Accordingly, it is an object of the present invention to provide an apparatus for the forming of suitable moldable material plaques which are relieved for use in the art of printing, the apparatus being characterised by the provision of a table top, the surface of which is magnetized for securing thereto independently related, individual molding elements which may be arranged as desired upon the table top to constitute a matrix for molding the desired printing plaque.
Another object of the present invention is to provide such an apparatus with means for successively heating and cooling the molding material applied in fluent condition to the aforesaid magnetized top surface of the apparatus.
Another object of the present invention is to provide such an apparatus wherein the independently related plaque molding elements are secured to the table top in any desired relation by magnetic force.
Still another object of the present invention is to provide such an apparatus wherein the several individual plaque-holding elements are fixedly held in position under the influence of the magnetic force exerted by the magnetized table top even when the formed plaque is lifted from the table top.
Still another object of the present invention is to pro vide an improved method of molding plaques relieved for use in the art of printing whereby it becomes economical to produce the plaques as use for them arises instead of storing them after each use.
And, finally, it is among the objects of the present invention to provide an improved method for producing printed curtains whereby the printed field leaves no lines between letters of a printed word or name which need to be obliterated by brushing or otherwise.
Other objects and advantages of the present invention will appear more fully hereinafter, it being understood that the present invention consists in the combination, construction, location and relative arrangement of parts, as well as in the method of producing plaques for use in the printing of curtain signs and the like, all as will be more fully described hereinafter, as is shown in the accompanying drawings and Will be pointed out in the appended claims.
In the accompanying drawings, which are illustrative of a preferred form of apparatus constructed in accordance with and embodying the principles of the present invention:
Figure 1 is a front elevational view of the apparatus of the present invention;
Figure 2 is a plan view of the apparatus of Figure 1 taken on line 2-2 thereof;
Figure 3 is a side elevational view of the apparatus of Figure 1 taken on line 33 thereof, parts being omitted for the sake of clarity;
Figure 4 is similar to Figure 3 but shows the lid of the apparatus open and a plaque removed therefrom, the latter and other parts being shown in section for the sake of clarity;
Figure 5 is'a sectional elevation taken on line 55 of Figure 1;
Figure 6 is a plan sectional view taken on line 66 V of Figure 4, parts being broken away to expose others;
Figure 7 is a plan sectional view taken on line 77 of Figure 4, parts being broken away for the sake of clarity;
Figure 8 is an enlarged view of the encircled area of Figure 6;
Figure 9 is a bottom view of the plaque shown in Figure 4, being taken on line 99 looking at the surface in which the letters are formed in hollow relief;
Figure 10 is a view of a printed curtain looking at the exposed surface thereof;
Figure 11 is a sectional elevation takenon line 1111 of Figure 6; and
Figure 12 is a perspective view of a magnetized element.
Referring to the drawings it will be seen that the plaque molding apparatus of the present invention essentially comprises a floor supported substructure 16 carrying a molding table 17 having a lid 18.
The substructure 16 is in the form of a rigid open supporting frame structure'which is rectangular in plan view and carries the molding table 17 at a convenient working height from the floor.
The molding table 17 includes a rectangular bed plate 19 of a heat conducting material, such as cast iron, fixedly secured in a suitable manner to the frame structure 16 and supported thereby in a horizontal position.
The bed plate 19 has formed therein a plurality of parallel through passages 21 which extend fore and aft of the bed-plate and are spaced more or less uniformly across the full width of said bed-plate. One end of each passage 21 freely communicates with the corresponding end of its next adjacent passage 21 by way of a channel 22 formed in a header member 23 secured to the edge of the bed-plate to overlie the communicating ends of each adjacent pair of the passages 21, the header members being disposed in staggered relation along opposite edges of the bed-plate so as to interconnect all of the passages 21 to provide, in effect, a single passage extending sinuously through the bed-plate. A gasket 24 is disposed between each header 23 and the bed-plate 19, the joint therebetween being rnade tight by drawing up a set of studs 26 projected through the header 23 and threadingly engaged by bed-plate 19. One end of the sinuous passage is suitably connected with a pair of valved inlet conduits 27 and 28, respectively connected to a suitable supply of a heating medium, such as steam, and to a suitable source of a cooling medium, such as water, while the opposite end thereof is suitably connected with another pair of valved discharge conduits 29 and 31, as is best shown in Figure 7. p
I Mounted upon the bed-plate 19 of the molding table 17 to completely overlie the upper surface thereof is a plate 32 of suitable heat-conducting, non-magnetic material, such as brass, said plate having formed therein a plurality of closely spaced apertures 33. tures, which are spread over substantially the full area of the plate 32, are each in the form of a circular open ing having coaxial bores of different diameters, the larger bore presenting downwardly and the smaller upwardly so as to provide therebetween a sharply defined internal annular shoulder. Each aperture 33 has fitted therein a permanent magnet 34 in the form of a round, plug-like member having a reduced upper end portion 36 rising from a sharply defined annular shoulder 37, which latter is adapted for disposition in abutting relation to the complementally formed internal shoulder of the aperture 33. Thus, when the several magnetic elements 34 are respectively socketed in the counterbored apertures 33, the upper surfaces of the elements are all disposed exactly flush with the upper surface of the plate 32. The magnetic elements 34 are preferably press-fitted into their respective sockets and provide the bed-plate 19 with a horizontally disposed, flat top surface having therein a relatively large number of permanently magnetized regions which are uniformly closely spaced throughout substantially the full area of said top surface. Preferably, the magnetic elements 34 are of the type formed of permanent magnetic alloy material, such as Alnico manufactured and sold by the Crucible Steel Company of America.
Preferably, the plate 32 in which the several magnetic elements 34 are set is itself completely covered by a relatively thin sheet metal plate 38-, preferably formed of polished steel, said plate 38 being removably held in secure position by the permanent magnets and being itself magnetized by the latter to provide a smooth, uniform, imperforate surface which is magnetized throughout its full area. A pair of flat bar members 39 and 41 are suitably secured respectively to opposite longitudinal edges of the plate 32, and a similar pair of members '40 are secured respectively to opposite transverse edges of the plate 32, all of these members projecting above the surface of the overlying plate 38 to provide raised marginal edges for the latter.
The lid 18 of the molding table 17 includes a rectangular top member 42 suitably formed of metal and preferably reinforced by a plurality of external ribs 43 extending lengthwise thereof. Formed integrally with said top member 42 are a pair of laterally spaced rib members 44-44 which extend transversely to provide These aperalt) overhanging parts 45-5 at the rear edge of the top member. Those overhanging parts constitutehinge' butts which are suitably apertured to respectively receive hinge pins 46-46 by means of which said top member 42 is hingedly connected to a pair of complementary hinge butts 4'747 formed as integral, rearwardly extending parts of the fixed bed plate 19 of the molding table.
The lid 18 also includes a rectangular bottom member 48 fixedly secured in a suitable manner to the bottom of member 42, the member 48 being adapted to be positioned, when the lid 18 is closed, in superimposed vertically spaced relation to the bed-plate 19, the lower surface thereof being disposed in approximately the same plane as the supper edges of members 39, as at) and 41. The member 48 is provided with a sinuous passage formed in the same manner as the sinuous passage in the bed-plate 1%, the opposite ends of the passage 49 being suitably connected respectively with valved inlet conduits 2'i 28 and valved discharge conduits 29 31 as see Figure 2. As in the case of the supply conduits to the bed-plate 19, the conduits 27 and 28 associated with the lid member are respectively connected to suitable supplies of heating and cooling media.
. For raising and lowering the hinged lid 18, a pair of fluid-pressure units 51--51are preferably employed, these units being respectively located at opposite sides of the apparatus. Each unit 51 comprises a cylinder 52 associated in a conventional manner with a piston 53, the lower end portion of the cylinder 52 being pivotally connected, as at 54, to a bracket 56 supported in a suitable manner on the substructure 16, while the upper end por tion of the piston 53 is pivotally connected to the side of the lid 18, as at 5'7. in this connection, it will be noted that each pair of the pivots 54-54 and the pivots 5757 are axially alined, and that the fluid pressure devices are of the double acting type to efiect positive swinging movement of the lid 13 about the hinge pins 46-46 between the closed position thereof shown in Figure 3 and the open position shown in Figure 4.
Arranged on the molding table 17 in abutting relation to one another to form an endless open frame, preferably rectangular in outline, are mold-forming elements 585S and 59-5 in the form of flat bar members of uniform thickness and of a magnetic material, such as steel. Within the frame elements 58-58 and 5959 other molding elements in the form of letters 61 are arranged to form any suitable word, such as Chartered shown in the drawings. The letters are made of flat steel stock of uniform thickness, the thickness being preferably less than that of the elements 5858 and 59-59, with the marginal edges of each letter beveled, as at 62, so as to permit the molded plaque to be readily stripped from the molding form. It will be noted that the elements 58-58, 59-59 and 61 are independently related, i. e., are without mechanical connection with one another and that they may be relatively disposed as desired upon the magnetized surface of the plate 38 to form a printing plaque of any desired wording and form, the several elements being secured firmly in their predeterminedly related position by the magnetic "attraction between them and the magnets 34 underlying the plate 38. Of course, as many different fonts of the letters 61 may be initially prepared as may be required, the same being thus available for repeated use as molding elements to form any desired printing plaques.
In the operation of the apparatus, as the pistons 53-53 are extended by introducing fluid under pressure into the cylinders 5252 from any suitable source of fluid pressure supply, the fluid pressure units 5151 swing rearward in vertically disposed, parallel planes about their axially alined bottom pivots 54-54 at the same time that the lid rotatesrelatively to the upper ends of the extended pistons about the axially a'lined upper pivots 57-57, in consequence of which the lid 18 swings up- With the lid 18 in its open position the mold-forming elements 58-58 and 5959 are suitably arranged upon the magnetized surface of the molding table to form an open frame as shown, following which the individual letters or characters 61 are suitably arranged within the frame to spell out any desired word or name, e. g., Chartcred, as shown in Figure 6. As previously described, the several elements 58, 59 and 61 are all magnetically attracted to the surface of the plate 38 and are held securely in their predeterminedly related position.
The material of which the plaque is to be formed, preferably a thermoplastic material which flows freely at a temperature of approximately 300- F., e. g., butyrate acetate, one form of which is manufactured and sold by the Pacific Plastics and Chemical Co., Redwood City,
California, under its trademark Plasteen, is reduced to a fluid condition by any suitable means and in fluid state is poured over the magnetically fixed elements 61. The fiuid material is evenly flowed over the level surface of plate 38 to completely cover the elements, enough of the fluent material being poured to raise its level flush with the upper surfaces of elements 58-58 and 959, which latter serve as a confining dike for the material poured over the mold-forming letters.
Prior to pouring of the fluent plastic material into the prepared mold, the valves of the steam inlet conduit-s 27 and 27 to both the bed-plate body member 19 and the lid body member 48 are opened, as'are the valves of the steam outlet conduits 29 and 29 simultaneously as the valves for controlling the flow of cooling water through said body members are closed. Upon opening the steam circulating valves, steam at about 300 F. is introduced into and circulated through the sinuous passages formed in the molding table and the lid, to thoroughly heat the molding surfaces of the apparatus t-o a temperature approximating that of the poured plastic material. The latter material is then poured into its prepared mold to cover the mold-forming letters, the lid is closed by actuation of the fluid-pressure units 5151, and steam is continued to be circulated through the molding table and lid for a period of time, approximately ten minutes, to promote uniform flow of the plastic material to every part of the prepared mold and to insure expulsion of all air bubbles from the plastic material.
Thereafter, the steam circulating valves are all closed and the water circulating valves, in the inlet and outlet conduits 28Z3 and 31-31% are all opened, whereupon cold water is circulated through the sinuous passages of the molding table and lid to cool the same and set the plastic material into relatively hardened condition.
Upon such cooling of the plastic material, the lid 18 of the apparatus is opened, as above described, the set and hardened plastic material being then stripped from its mold as the printing plaque 63 shown in Figure 9, wherein, it will be seen that the finished plaque 63 is in the form of a fiat rectangular member having a relieved printing surface the depressions of which form a negative of the Word to be printed, e. g., Chartered.
In using the plaque 63 for printing a curtain sign 64 (see Figure l0) ink contrasting in color to that of the curtain material is applied to the printing surface of the plaque, the latter is placed transversely across the curtain with the printing surface thereof in contact with the curmin and suitable pressure is applied to impress the ink upon the curtain. It will be seen that the field printed by the plaque leaves the word, e. g., Chartered, displayed on the curtain in the color of the curtain material and since the printing surface of the plaque is unbroken between the depressions therein, no lines are formed between the letters which need to be brushed out or otherwise obliterated. Besides this advantage it will be readily understood Instead of using one plaque at a time, several different plaques may be used. In this event the procedure for printing a curtain is similar to that just described except that-the plaques are placed in abutting relation to one another on the curtain. The field printed is then broken by lines formed where the proximate edges of the plaques abut one another and to get a solid, uniform field these lines must be brushed out or otherwise removed.
In any case, after a plaque has served its immediate need, it may be reduced to a fluid condition to provide material which maybe reused to form different plaques as need for them arises. In this connection, although the present invention has been described as employing a thermoplastic material, it Will be understood that other materials may be found suitable for use. Any nonmagnetic material which flows freely at about 300 E, which sets at a lower temperature, and which will not adhere to the molding apparatus, may be found suitable for use. In addition, it is essential to reduce to a fluid state the material of which the plaque is to be formed preliminarily toits application over the magnetically fixed elements 61. Thus, the thermoplastic material may be applied over the prepared mold surf-ace in the form of a preformed solid sheet of requisite thickness so that upon the application of heat and pressure the surface thereof immediately overlying the mold elements (iii the latter will be pressed into said surface and so form therein negative impressions of the prearranged magnetically secured elements. Still further, neither the perimetric form of the plaque nor the sign itself is limited to that shown, but either or both may be changed by suitably changing the number and/ or arrangement of the mold-forming elements on the molding table.
For example, the elements 5%58 and 59-59 may be dispensed With, and the full area of the molding table 17 may be used, the plaque thus formed having a length corresponding to the distance between members sen-4a and a Width corresponding to the distance between members 39 and 41. Also, whether or not the full area of the molding table 17 is used, the plaque may be formed to print two or more lines of lettering. In this connection, it will be noted, for example, that by using the full area of the molding table 1'? and suit-ably arranging the elements at thereon along spaced lines extending transversely across the Width of the table, there may be formed a plaque capable of printing a curtain corresponding in size to that of the magnetized plate 38.
It will be understood that the molding apparatus of the present invention is provided with suitable means (not shown) for controlling the fluid pressure units 51-51, and if desired, these units may be entirely dispensed with in favor of any suitable arrangement for manually opening and closing the top lid of the apparatus and for applying adequate pressure thereto. Furthermore, the controls for the steam and cold water need not be manual, but may that handling a single plaque which will print an entire be automatic, and may be arranged to operate independently of, or in timed relation with, the fluid pressure units 5151.
From the foregoing, it will be evident that a molding apparatu has been provided with novel means for conveniently and quickly molding a plaque having a printing surface hollow relieved to form sharply defined letters or characters of any place names or words, such as conventionally appear on vehicle destination signs of the roller curtain type. Furthermore, the apparatus affords a novel method for forming such a plaque, this novel method making it economical to produce plaques as need for them arises, instead of storing them after each use, thus saving storage space and reducing the investment in plaques. Still further, the plaques, produced by this novel method afford a novel method of producing a printed curtain because the field printed by such a plaque is solid and uniform between the letters or characters forming integral elements of the plaque.
It will 'be understood, of course, that the present invention is susceptible of various changes and modifica iqns which may be made from time to time without departing from the real spirit or general principles thereof, and it is accordingly intended to claim the same broadly as Well as specifically, as indicated in the appended claims.
What is claimed as new and useful is:
1. In an apparatus for molding plaques relieved for use in the art of printing comprising a horizontally extending table top, a plurality of elements arranged upon said table top and coacting with the latter to conjointly provide an upwardly presenting mold oi predetermined shape and character, a lid for said table top, and means for closing said lid, whereby said mold forming elements are sandwiched between the latter and said table top and pressure is brought to bear on the material with which the mold is charged, said table top including a bed plate, a plurality of permanent magnets distributed over the top of said bed plate and fixed thereon, a cover plate extending over said bed plate and permanent magnets and magnetized by the latter whereby to magnetically L attract said mold forming elements and shiftably removably secure the same in place, said bed plate and lid being each provided with a valved pass-age connected with sources of fluid media, the passage controlling valves being operable for admitting to said passages a heating medium, whereby the surfaces between which said element are sandwiched are heated, or optionally a cooling medium whereby the surfaces aforesaid are cooled, pressure and heat thus applied to the mold charge being effective to expel all air bubbles from the mold charge and to promote rapid flow of the mold charge into every part of the mold cavity, and the cooling medium being effective to promote hardening of the mold charge without undue delay.
2. In an apparatus for molding plaques relieved for use in the art of printing as defined in claim 1 wherein the lid is positioned upright at the rear of the table top and connected to the bed plate for swinging forwardly and downwardly about a horizontal axis to a horizontal position over said table top, the valved pass-ages are sinuous, being arranged to carry the fluid media to all areas of said bed plate and lid, a non-magnetic plate is interposed between said base plate and the cover plate,
8 and the permanent magnets are set respectively in apertures formed in said non-magnetic plate, the tops of said permanent magnets being flushwtih the upper surface of said non'magnet-ic plate and in contact with the undersurface of said cover plate.
3. in an apparatus for molding plaques relieved for use in that art of printing as defined in claim 1 wherein the lid i positioned upright at the rear of the table .top and connected to the bed plate for swinging forwardly and downwardly about a horizontal axis to a horizontal position over said table top, said bed plate and lid members are each provided with a plurality of laterally spaced generally parallel principal passage sections extending through the member generally parallel to the plane thereof, means respectively abutting the peripheral edges of aid members :coaet therewith to form cross passage sections each of which places the corresponding ends of a pair of adjacent principal passage sections in communication, whereby to form the passages for said fluid media, said passages being sinuous for conducting said fluid media to all areas of said members, a non-magnetic plate is interposed between said base plate and the cover plate, and the permanent magnets are set respectivly in apertures formed in said non-magnetic plate, the top of said permanent magnets being flush with the upper surface of said non-magnetic plate and in contact with the undersurface of said cover plate.
Referenees Cited in the file of this patent UNITED STATES PATENTS 643,422 McFarland Feb. 13, 1900 1,377,501 Novotny May 10, 1921 1,398,149 Nov-otny Nov. 22, 1921 1,436,941 Burcka-rd Nov. 28, 1922 1,806,846 Fox May 26, 1931 1,897,893 Evans Feb. 14, 1933 2,094,823 Sample Oct. 5, 1937 2,465,276 Ryder Mar. 22, 1949 FOREIGN PATENTS 511,230 France Dec. 20, 1920 556,396 Great Britain Oct. 4, 1943