US1828739A - Plate holder for photographic printing machines - Google Patents

Description

Oct. 27, 1931. w. c. HUEEBNER PLATE HOLDER FOR PH OTOGRAPHIC PRINTING MACHINES Original Filed Aug. 8, 1928 a Sheets-Sheet 1 cllll XIII I 4 In I In I" I Oct.'27, 1931'. w. c. HUEBNER' 1,323,739

PLATE HOLDER FDR PHOTOGRAPHIC PRINTINfi CHINE-5 Original Filed Aug. 8, 1928 3 Sheets-Sheet 2 Oct. 27, 1931.- w. c. HUENER 1,828,739

PLATE HOLDER FOR 'PHQTOGRAPHIC PRiNTING MACHINES Original Filed Aug. 8, 1928 3 Sheets-Sheet 3 I l v I m; +12 I v 77 J I I: 76 Q X 0 U e &0

(9 v (4 Q 76' 1.7 L, G K I 77 O i +12 5 W/ 92 7.4 Y 1% F 593. if aw 1770977202; WEZZzam CTHzeZmgr ing and especially a series of color press 'Patentedfioct. 2 7, 1931 UNITED s'rATEs PATIENT OFFICE WILLIAM C. OF ILLINOIS, ABSIGNOB 1'0 HUENER'BLEISTEIN PATENTS COMPANY, OF BUFFALO, NEW YORK, CORPORATION OF NEW YORK PLATE HOLDER IOR 'REGTOGBAIHIC PRINTING MACHINES Application flled-August 8.1928, Serial No. 298,256. Renewed March 14, 1931.

This invention relates to improvement; in plllate holders for photographic printing mac mes.

In the art of making press'plates for printplates, extreme accuracy is required in registering the photographic prints or im ressions of the several images usually ma e on each press plate, commercial practice requiring that such registering be maintained within 3/1000 of an inch.' In making such platesin photographic printing machines, it is customary to have the sensitized press plate flat while the exposures are made. Heretofore, it has been the universal practice, so far as I am aware, to employ two opposed sets of adjustable clamping jaws on two opposite edges of the plate and then separate the jaws to make the plate taut, the other two edges of the plate being unsecured; Due to the fact that it is necessary, in most instances, to work close to the edges of the press plate in making the impressions so as to utilize all of the available area, it has also been necessary to locate the clamping and stretching jaws below the level of the sensitized surface of the plate in orider to prevent the jaws from scratching or fouling the usual glass negatives, portions of the latter being necessarily extended beyond the edges of the press plate when making anexposure near the edge of the latter. Hence it has resulted that two of the edges of the press plate have been bent around the corners of some fixed or stationary parts of the plate holder or machine, while the other two edges of the press plate have been free or unsecured.

Great difiiculty has always been experienced in obtaining the desired accuracy of registration and location of the prints on the press plate. due to the fact that the clamping and stretching arrangements in use, as above described. have been inadequate in making the plates absolutely fiat. The bending of the plates around corners of. the holder or machine has resulted in producing waves in the plat which no amount of stretching can quite eliminate and these waves, together with others permitted by reason oflthe two unsecured edges of the plate, produce misregister when the exposure print is being made under pressure from the flat glass negative, it being evident that the waves will shift from point to point in the press plate as the curing and stretching the plate taut in an ab solutely flat condition throughout its entire area and free from any buckling or waves,

said means being further characterized'by the fact that there are no parts or portions thereof projecting above the surface of the press plate so that the negatives may be extended eyond the edges of the press plate and pressure applied during exposure when making prints or impressions adjacent the edges of the press late; Y

Another 0 ject of my invention is to provide a holder having the characteristics above indicated wherein the holder is portable so that the press plates may be attached thereto while the holder is out of the photographic printing machine proper, to the end that the plates may be changed more rapidly and with a minimum delay to the use of the photographic printing machine;

Another object of my invention is to provide a holder of the character indicated in the preceding, so arranged that a vacuum seal may be obtained with a cooperating vacuum negative holder in any position of the negative relative to the press plate and whether or not the negative holder is disposed within the area of the press plate or is partly extended beyond an edge thereof Other objects of the invention will-more clearly appear. from the description and claims hereinafter following.

In the drawings forming a part of this specification, Figure 1 is a plan view of an improved holder showing my improvements incorporated therein. In his figure a press plate is shown applied to the holder and certain parts are broken awa to more clearly illustrate underlyingstruc ure. Figure 2 is a sectional view upon an enlarged scale corresponding substantially to the line 2-2 of Figure 1. Figure 3 is an end elevation of the structure illustrated in Figure 2. Figure 4 is an enlarged broken plan view of the holder corresponding to the lower lefthand corner of the holder shown inFigure 1. Figure 5 is a sectional view corresponding to the line 5-5 of Figure 2. Figure 6 is a vertical sectional view corresponding to the line 6-6 of Figure 4. Figure 7 is a transverse sectional view corresponding to the line 7+7 of Figure 6. Figure 8 is a plan view of the holder proper similar to Figure 1 but with an asso-' ciated parts removed. Figure 9 is-a part plan view, part'sectional view illustrating more particularly one of the adjustable attaching and stretching members at the corner of the holder. Figure 10 is a detail sectional view corresponding to the line-101O of Figure 9-. Figure 11 is a view similar to Figure 1 illustrating a modification in the means for at-.

taching a glass plate and in the masking or extension means associated therewith; Figure 12 is an enlarged sectional view corresponding to the .line 12-12-of Figure 11. Figure 13 is a view similar to Figure 12 illustrating the holder modified to retain a copper or like thick plate. I

In the drawings, and referring first to the construction illustrated in Figures 1 to 10, inclusive, A indicates the holder proper; B a press'plate of the usual flexible character; C portions of a photographic printing machine to which the holder is adapted to be secured; and D, E and F extension plates, the function of which is described hereinafter.

The holder proper A (particular reference being had to Figure 8..and the sectional views) preferably comprises a rectangular heavy base or plate 20, of sufficient size to accommodate the maximum size press plate and theextension lates as hereinafter described. Said plat O has an upper perfectly flat surface and slidably mounted thereon are two attaching and stretching members 21-21; a third attaching and stretching member 22; and two diagonally disposed attaching and stretching members 23.23. The two members 21 are placed in alinement near the upper edge of the holder and each is slidably mounted in a corresponding recess 210 out in the plate 20. Each member 21, as best illustrated in Figures 2, 3 and 5, is preferably a built up construction comprising a slide block 211 and a top plate 212. The block 211 has adownturned angular extension at its outer end, as indicated at 213, into which is threaded an adjusting screw 214,'having a knurled head 215, said screw being swiveled in a downturned flange 216 preferably formed integral with the plate 20. The plate 212 is made exactly flush withthe surface of the main plate 20 and, by adjusting the screw 214, it is evident that the built up member erably held in lace by a bottom plate 216 and interposed locks 217 secured to the underside of the-main plate 20 bysuitable s screws 218. Each plate 212 is provided with an alined series of countersink openings 219 in its upper surface, the purpose of which will'appear hereinafter. The member 22 is constructed and operated similarly to the members 21 but is disposed at the lower end of the holder and movable in a direction at right'angles -to the line of movement of the members 21-21. Detailed description of its construction is not deemed necessary.

In the case of the diagonally disposed members 23, which are at the lower corners of the main holder proper, the following con struction. is employed. Preferably cast to the'underside of the main plate 20. is an elongated substantially rectangular housing 231 between the lower wall 232 and the top wall 233 of which is slidably adjustable the member 23. The latter is adjusted back and forth in the same manner asin the case of the members 21, that is, by an adjusting screw 234 swiveled in a depending flange of the main plate and having threaded engage ment' with a depending lug 235 which is pivotally connected to the member 23 by a pin 239. The lug 235 is guided in its back and forth movements by guide plates 50 which extend into corresponding slots 51, as best shown in Figure 7. The port-ion 233 of the main plate is provided with an alined series of openings 236 arranged diagonally and in each of said openings is an upwardly extended integral boss 237 of lesser diameter than the corresponding opening 236, the upper faces of the bosses 237 being flush with "the surface'of the main plate 20,. Each of said bosses has a counterbore 238 and a threaded opening therebelow for the purpose hereinafter described.

, Referring more particularly to Figures 9 and 10, the inner end of each member 23 has slidably mounted in an elongated slot 52 thereof, a small block 53, the latter being disposed parallel with the length of the member 23. Said block 53 is in turn pivotally connected bya pin 54 with a nut block 55, held in place by guide plates 5656. The nut block 55, which ismovable perpendicularlyto the side edge of the holder has threaded engagement with an adjustingQscrew 57 extended beyond the corresponding side of the holder where said screw is provided with a preferably knurled nut 58 for adjusting the same.

With the arrangement of members 23 as above described, it is evident that the same may be adj usted back'and forth in a direction extending diagonally of'the holder and also that the inner end thereof may be adjusted the main plate 20.

laterally to a slight extent b means of the screw 57, for the purpose ereinafter described.

In carrying out my invention, the press plates B, when the same are of relatively thin sheet metal and flexible, as used in the great ma'ority of instances,'will referably be 'provi ed with six counterpunc ed openings, one at each corner,"as indicated at 59, 60, 61 and 62 and with two other similar counterpunched openings, as indicated at 63,

6 t at the centersof the-top and bottom edges.

In applying the press plate B to the holder, the latter will preferably first be secured by acountersunk screw 631 at, the top center which is entered throu h a corresponding countersunk and threa ed opening 632, in

Next, the two corners 59 and of the press plate will be similarly secured by countersunk headed screws to the proper openings 219, in the adjustable stretching 'mem bers 2121,. the series of openings in the latter bein provided to accommodate press plates B 0 different widths. Next. he corners 61 and 62 of the press plate and the center point 64 will be similarly secured to the di-' condition. Next. the member 22 will be adagonally adjustable members 23 and mem ber 22, respectively. In making the plate taut, the two members 2121 will first be adjusted outwardly so as to place the top edge'of, the plate in perfectly flat and taut justed so as to pull the plate taut in a difreetion at right angles to the first stretching and in the vertical center line thereof.

" Finally, the two diagonally disposed members 23 will be adjusted to pull the corners taut and in this connection, should there be any slight misalinement of the punch holes 61 and 62 with respect to the bosses 237, the

slide members 23 may be laterally shifted to efi'eet the alin ent by means of the adjusting screws 57. In the manner above described, it is evident that the press plates are held perfectly fiat throughout their entire area on the holder Aand, further, that there are no attaching devices or other members extending above the usual sensitized surface. of the press plates so that there is no danger of fouling a negative when the latter is used to make impressions.

As he'reinbefore indicated, when prints -or impressions are made near the edges of the press plate, it is necessary that portions of the usual negative or negative holder be extended beyond the edges of the press plate and it is further necessary that proper pressure be obtainable between the negative and press plate in this extended or overlapped condition. Where the vacuum system is used in obtaining this pressure, a'perfectair seal must also be provided.

For thesepurposes, I employ what may be termed .masking or extension plates D, E

and F.' 'The former is extended lengthwise of the top edge of the holder and always bears a fixed p being prefera ly of sheet metal and corre-' spending .inthickness in each instance, to the press plate B. It is secured in position by suitable countersunk screws 64. The two side extension plates EE, also of the same thickness as the press plate in each instance, are adapted 10 be adjustably mounted on the holder A in different positions corresponding to the different widths of the press plate. For this purpose, the holder A is provided with an upper series of countersunk threaded openings 65-65 and a lower horizontally extending series of similar openings 66-66. The plates E are secured in the osition thereon, said plate D proper sets of openings as will be underedge of the plate B, it will have full bearing on a perfectly flush flat surface throughout.

In actual practice, slight Variations are tolerated in the different sizes of press plates B so that it is not entirely practical to have the edges of'the side plates-E and bottom plate'Fv always in abutting contact with the corresponding edges of the press plate, with the result that slight gaps will be left between the extenson plates and thepress plate, which gaps, in the case of employing-vacuum for effecting the pressures between the negative and the press plate, might destroy the necessary air seal; To overcome this ditti culty, I preferably employ a thin rubber sheet,.as indicated at 7 0. which underlies the i press plate B and all of the extension plates D, E and F,'this thin rubber sheet being suitably -cut out to accommodate the several fastener screws of the press plate and extension plates. With this construction, as best indicated in Figure 2, when the vacuum is on, the rubber sheet will be drawn up into the gaps between the extension plates and the press plate, thus positively insuring an air seal entirely around the press plateand also in the gaps which may exist between the ends of the extension jacent extension.-

To renderthe holder A portable, there are preferably secured to the undersideof the main plate 20 along the top and bottom edges thereof, two bars 68 and 69, the ends of which plates and the sides of an adthe machine are extended. The bar 68 is preferably provided with a. circular opening 70 at one end adapted to hook over a shouldered lug 71 on the portion C of the machine proper and, at its other end, the bar 68 is provided with an enlarged preferably square opening 72 adapt-' ing it to be hung on a corresponding square lug 73. The holder is securely clamped to by suitable cam levers 7474, at all four corners.

Referring next to the construction illustrated in Figures 11 and 12, theholder A is the same as previously described. In this i nstance, I have illustrated the use of my holder when a glass plate G is to be used instead of I the more common zinc or aluminum pre s plate, as, for instance, in making up a composed positive for group negative purposes. In this construction, the glass G, as customary, is provided with beveled edges 75 at its top and bottom edges and is adapted to be secured by clamping jaws 767 6, each of which is adjustably retained in proper clamping position by a pair of headed screws which work in elongated countersunk openings 78 in the upper faces of the clamping bars.

To provide the necessary extension of the glass plate, I preferably employ a single extension rectangular frame 79. These will preferably be made in different sizes with the central openings .80 thereof approximating the over-all dimensions of the glass plates G with their attaching clamps. The extension frame 7 9 is secured in place by suitable countersunk screws thereof.

In this arrangement, in order to insure the proper air seal for use when vacuum is employed, I preferably employ a thin rubber sheeting 82 which, in this instance, overlies the extension frame 79 and underlies the clampin jaws 76 and glass plate G, as best illustrated in Figure 1 In this manner, the

- proper seal is insured in the gapssurrounding the plate G. As will be understood, the clamping jaws 76 and the extension frame 79 are made flush with the surface of the. glass plate G In actual practice, there will preferably employed a .layer of black velvet beneath the glass plate G when exposure is made, in order to prevent refraction of the light rays which might distort the photographed image, but I have not deemed it necessary to illustrate this layer of velvet.

In the modification shown in Figure 13, where a copper plate H is indicated having square edges'83, the clamping jaws 84 are correspondingly modified to engage the square edges and to prevent the plate H from falling out during handling of the-holder A, strips of paper or tape 84 'may be fastened to the adjacent edges of the clamps andplate, as clearly shown-in the figure. In this arout the invention,

81 at the four corners rangement, a similar thin -sheet of rubber 82 will be employed, the same overlyin the extension frame and underlying the c amping jaws 84 andthe plate H. As in theprior described constructions, all surfaces will be made flush for the purpose indicated.

I have herein shown and described what I consider the preferred manner of carrying but the same is by way of not by way of limitation.

illustration and All changes and plated that come within the scope of the claims. appended hereto.

, I claim:

.1. In a press plate holder, the combination with a supporting bed for a rectangular plate; of a pair of members oppositely adjustably mounted on' said bed .in substantially the same line substantially parallel to one edge of the plate' two diagonally adjustably mounted mem ers on said bed; and means for attaching adjacent portions of the plate to each of ,said members. i a

2. In a press plate holder, the combination bed for the plate; of a with a supporting pair of members oppositely adjustably -mounted on said bed in substantially the same line; two'diagonally adjustably mounted members on said bed; means for attachiing adjacent portions of the plate to each of said members; a pair of diagonally adjustably mounted members onsaid bed; another member adjustably mounted on said bed in a direction at right angles to the first-men'- tioned pair of members and at the opposite side of the bed; and means for attaching adjacent portions of members. 3. In a press plate holder, thecombination a plate to each of said -w1thsupporting means for a press'plate; of

a plurality of members adjustably mounted on said means in lines extending parallel, perpendicular and. diagonally with respect to the edges of the press plate; and means for attaching adjacent portions of the press plate to said members.

7. modifications are contemi countersinks therein for the reception of cor-- responding countersunk portions of the plate and countersunk fasteners, whereby said portions of said devices eners are maintained flush or below the surface of the press plate.

5. In a press plate holder, the combination with means for supporting a press plate; of devices on said means for stretching a" press including the fastplate taut thereon, said devices including movable elements eachhaving a portion flush with the supporting sur ace of said means,

saidsupporting portions having countersinks therein for the reception of correspondtions of said devices including the fasteners are maintained flush or below the surface of the press plate, each of said elements being slidably mounted with respect to the supporting means.

6. In a press plate holder, the combination with means for supporting a press plate; of devices on said means for stretching a press plate taut thereon, said devices including movable elements each having a portion flush with the supporting surface of said means,

said supporting portions having countersinks therein for the reception of correspond: ing countersunk portions of the. plate and countersunk fasteners, whereby said portions of said devices including the fasteners are maintained flush or below the surface of the press plate, said elements being movable in a plurality of directions at angles to one another. 7 In a press plate holder, the combination with main supporting means; of combined stretching and attaching elements movably mounted on said means, each of said elements having a portion on which the plate is adapted to lie and a countersink for a correspondin countersunk portion of the plate; an a headed fastener securing said countersunk portion of the plate, with the head of the fastener disposed flush or-below the exposed surface of the press plate. 8. In a press plate holder, the combination with main supporting means: of combined stretching and attaching elements slidably mounted on said means, each of said elements having a portion on which the plate is adapted to lie and a countersink for a corresponding countersunk portion of the plate and countersunk fasteners; and means for adjusting and retaining said elements in adjusted position.

9. In a holder of the character described, the combination with a supporting bed of greater area than the area of the print-receiving plate to be used thereon; means for securing said print-receiving plate on said bed with the entire area thereof flat; and extension means on said'bed flush with the printreceiving plate and surrounding the latter whereby an opposed negative may overlap the edges of the print-receiving plate and have pressure applied thereto for exposure, all portions ofsaid securing means within the outermost peripheries of the plate and extension means being flush or below the sur- 9 face of the plate.

10. In a holder of the character described, the combination with a supporting bed of greater area than the area of the print-receiving plate to be used thereon; means for securing different size print-receiving plates to said bed; andlmeans flush with the print-receiving plate and disposed adjacentv the periphery thereof and surroundin the same and providing an extension therefor all portions of said securing meanswithin the outermost peripheries of the plate and extension means being flush or below the surface of the plate.

11. In a holder of the character described, the combination with .a supporting bed of greater area than the area of the maximum size press plate to be used thereon; of adjustable means on said bed for securing the press plate thereon fiat throughout its entire area; and means on said bed flush with the press plate and surrounding the same whereby to provide an extended pressure-bearing area, all portions of said securing means withm the outermost peripheries of the plate and extension means being flush or below the surface of the plate.

12. In a holder of the character described the combination with a supporting bed of greater area than the area of the maximum size press plate to be-used thereon; of adjustable means on said bed for securing the press plate thereon flat throughout its entire area;

and a plurality of extension plates on said bed and disposed around the adj acent edges of the press plate and having the surfaces thereof flush with the press plate, all portions of said adjustable securing means within the outermost peripheries of the press plate and extension plates being flush or below the surface of the press plate.

13. In a holder of the character described the combination with a supporting bed of greater area than the area of the maximum size press plate to be used thereon; of adj ustable means on said-bed for securing the press plate thereon flat throughout its entire area; and a plurality of extension plates on said bed and disposed around the adjacent edges of the press plate and having the surfaces thereof flush with the press plate, some of said extension plates being adj ustably mounted with respect to the be 14. In a holder of the character described, the combination with a flat bed plate; of a print-receiving plate; means for securing said print-receivin plate fiat throughout its entire area on saidlied plate; extension plate means secured to the bed plate and disposed around the ed es of the rintmeceiving plate; and a thin exible s eet underlying the print-receiving plate and extending outwardly beyond the edges thereof and adapted to provide an air seal at the gaps between the print-receiving-plate and the extension plate means.

15. In a holder of the character described, the combination with a flat bed plate; of a print-receiving plate; means for securing said print-receiving plate flat throughout its entire area on said bed plate; extension plate f as;

means secured .to the bed plate and disposed around the edges of the print-receiving plate; and a thin flexible sheet underlying-the rintreceiving plate and extending outward y beyond the edges thereof and adapted to provide an air seal at the gaps between the printreceiving plate and the extension plate means, said' sheet also underlying the extension plate means. i

16. In a press plate holder, the combination with a main fiat bed plate; of a pair 01? slidably adjustable stretching and attaching members near one edge of said bed plate; a pair of diagonally slidably adjustable stretching and attaching members also mounted on said bed plate; another stretching and attachin member slidably mounted at the opposite si e of said bed plate and movable .in a direction perpendicular to the first named edge; means for attaching a sheet metal press plate to each of said members,

said means including countersunk threadedopenings in each of said members and a countersunk screw; and a plurality of extension plates disposed around the periphery of the press plate, some of said extension plates being adjustably secured to the bed plate, the securin means therefor being also countersunkw ereby the stretching, attaching and extension means are all disposed substantially flush with the surface of the press plate.

' In witness that 1 claim the fore oing I have hereunto subscribed my name t is 2nd day of August 1928.

- WILLIAM C. HUEBNER.

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