US2914289A - Flexible sheet support for photographic device - Google Patents

Description

N. C. SCHUTT Nov. 24, 1959 FLEXIBLE SHEET SUPPORT FOR PHOTOGRAPHIC DEVICE Filed Nov. 12, 1957 2 Sheets-Sheet 1 y H I 75 INVENTOR. NoRMAN 62 5cm/TT .inl

A TTORNE Y6.

N. C. SCHUTT FLEXIBLE SHEET SUPPORT FOR PHOTOGRAPHIC DEVICE Filed N'ov. 12, 1957 2 Sheets-Sheet 2 INVENTOR.

s T .wy www@ w m s w C. A N f m W N ,wf/

United States Patent O FLEXIBLE SHEET SUPPORT FOR PHOTOGRAPHIC DEVICE Numan C. Schutt, Glen Cove, N.Y., assignor to Powers Chemco, Inc., Glen Cove, N.Y., a corporation of New York Application November 12, 1957, Serial No. 695,912

5 Claims. (Cl. 248-363) Thisinvention relates to a sheet support for use with large photographic cameras and, which may be used as either a copy or a film support and has specific relation t an improved support wherein a picture, or other sheet of copy or wherein a sheet of photosensitive paper is held flat and in intimate contact with the support by means of suction.

Objects and advantages of the invention will be set forth in part hereinafter and in part will be obvious hererom, or may be learned by practice with the invention, the same being realized and attained by means of the instrumentalities and combinations pointed out in the appended claims.

The invention consists in the novel parts, constructions, arrangements, combinations and improvements herein shown and described.

The accompanying drawings, referred to herein and constituting a part hereof, illustrate one embodiment of the invention, and together with the description, serve to explain the principles of the invention.

Of the drawings:

Figure 1 is a rear plan View of a preferred embodiment of the improved support of this invention with parts being broken away to better show the details of construction;

Figure 2 is a side View of the sheet support;

Figure 3 is a partial sectional view taken along line 3-3 of Figure 1 with the scale of Figure 3 being much larger than that of Figure 1;

Figure 4 is a sectional view taken along line 4 4 of .Figure l and showing in detail the detent that engages the valve actuating stem;

Figure 5 is a partial vertical sectional View of the sheet support and the distributor valve that forms a part there- -of with this section being taken along line 5 5 of Figure 1 and with the scale of this view being much larger .than that of Figure l;

Figure 6 is a partial'rear elevational view of the sheet support with tlie'rear wall of the distributor valve hous- .ing removed, and;

Figure 7 is a perspective view of the slide valve per se.

The present invention has for its object the provision lof an improved support for the exible sheet of copy or photosensitive paper in a precision photographic camera wherein the sheet is held in contact with the support by means of suction. A further object is to provide an improved support of this type wherein suction is applied to openings distributed over -the face of the support through a chambered manifold arrangement by means -of which suction may be applied to the entire area of the support or limited centrally located portions thereof and wherein this application of suction to these various chambers of the manifold and accordingly areas of the support is selectively controlled by a novel distributor valve mounted on the rear of the support. A still further object is to provide such a suction support of improved quality and wherein the distributor valve is operative to distribute the suction applied to the chambers of the mani fold in a manner to produce a generally uniform suction throughout the chambers to which suction is applied at any one time notwithstanding that the several manifold chambers serve areas of the support of different magnitude. Another object is to provide an improved suction type support wherein the manifold is comprised of nested chambers with the chambers being arranged so that the total areaof the openings communicating with each chamber and through which suction is applied to the tace of the support progressively increase with chambers outwardly of the center and wherein the distributor valve carries flow restrictors and is operative to successively restrict communication of the inner chambers relative to the outermost chamber to compensate for this so the suction in each chamber to which suction is applied will be generally uniform. Still another object of the invention is to provide such an improved suction type of support well adapted for use with cut film or with copy sheets of varying sizes or for use with roll film and which is rugged and reliable in its operation and wherein the distributor valve although effective to both control the area of the support to which suction is applied and generally evenly distribute the application of the suction throughout the area to which suction is applied is extremely simple and economical in construction yet is highly satisfactory in operation.

in accordance with the present invention there is provided a facing member which has openings distributed throughout its area and through which suction is applied to a flexible sheet that is positioned against the flat front face of this member. Overlyiug and in engagement with the rear face of this member is a backing plate which has passages extending therethrough and each of wh.cn communicate with only a particular group of openings in the facing member. This backing plate is provided with a series of rearwardly extending ribs or partitions, which, together with a cover plate overlying the rear face of this backing member, form a plurality of separate chambers with one chamber being located generally centrally with respect to the facing member and effectively covering a restricted central area of the facing member and with the other chambers positioned about and progressively outward of this central chamber. These several chambers together cover substantially the entire area of the baci;- ing plate and accordingly the facing member, and in the illustrative and preferred embodiment there are three such chambers. These chambers form a manifold for the application of suction to the openings of the facing member through the passages in the backing member, and the chambers and passages are arranged so that the total area of the passages that communicate with each chamber progressively increases from the centermost chamber outwardly with this being the result of sizing the chambers so that they are progressively larger outwardly of the centermost and also as a result of increasing the size of these openings in the upper central position of the outermost chamber and decreasing the spacing of the openings communicating with this outermost chamber. The application of suction to these nested manifold chambers and accordingly to the area of the film support corresponding or overlying them is controlled by a distributor valve that is mounted on the rear of the support. This valve is effective to not only control the application of suction to the chambers but also to compensate for the effect that the variation in total area of the passages in the backing member that communicate with the various chambers has with regard to the application of suction throughout the area of the support to which suction is applied, with the valve giving a substantial equal degree of vacuum to each manifold chamber.

' The distributor valve is of the slide type mounted in a suitable housing secured to the rear of the cover plate with the valve being maintained in sliding and valving relation with the cover plate and with a suitable operating stem extending laterally out through the side of the housing for moving the valve to and from its inner and outer positions. An opening extends through the cover plate from each of the manifold chambers into the housing and these openings and the valve are arranged so that when the valve is in its inner position it blocks all of the openings except that extending from the innermost chamber and upon moving the valve toward its outermost position the opening extending from the intermediate chamber is uncovered and a flow restrictor is positioned over the opening extending from the innermost chamber. This flow restrictor effectively compensates for the difference in total area of the openings in the backing plate that communicate with the inner most chamber and the intermediate chamber so that the vacuum in each of these chambers is substantially the same. Upon further moving the slide valve outwardly and into its outermost position the opening communicating with the outermost chamber is uncovered and a ow restrictor is positioned over the opening extending from the innermost and the intermediate chamber with these flow restrictors being effective to provide substantially the same degree of vacuum in each of the three chambers. The flow restrictors forproducing this desired result take the form of spring iiapper members secured to the slide valve.

Thus, the distributor Valve is operative to regulate the extent of the support to which suction is applied and is also effective to insure that a substantial equal suction effect is had throughout this effective area.

It will be understood that the foregoing general description and the following detailed description as well are exemplary and explanatory of the invention but are not restrictive thereof.

Referring now in detail to the drawings, wherein like reference characters are used throughout to designate like elements, the illustrative and preferred embodiment of the invention depicted therein comprises a facing plate having a dat outer surface and being provided with groups of openings 12 distributed throughout the area of the plate. The flat outer surface of plate 1t) is adapted to have a sheet of flexible material 13 placed over and in engagement therewith with the sheet being held in firm contact with the face of the plate by the application of suction through the groups of openings 12. Overlying the back of plate 1@ and in engagement therewith is the backing plate 14 which is cemented to plate 10 about the overlying edge of the two plates in a iiuid tight manner. The face of plate 14 that is in engagement with facing plate 10 is provided with relieved portions or recesses 16 each of which communicates directly with and encom passes one of the group of openings 12 provided in facing plate 10 with bores or passages 18 extending from the bottom of these relieved portions through the backing plate.

'Suction is applied to bores 18 through a suitable manifold located at the rear of backing plate 14 and to form this manifold partitions 22 are provided which extend laterally from and rearwardly of the packing plate and in overlying relation with which is cover plate 24. The partitions or ribs 22 are disposed as shown in Figure l vso, that with cover plate 24, which preferably engages the partitions in a uid tight manner, three separate charnbers 26, 28 and 30 are provided with chamber 26 preferably being located centrally with respect to backing plate 14 and facing plate 10 and being of rectangular shape while chambers 28 and 30 are disposed about this central chamber 26 and respectively progressively outward thereof. These nested chambers thus, in combination, cover the entire area of backing plate 14 except for the area that is occupied by partitions 22.

In order to control the application of suction to these chambers there is mounted on the back of cover plate 24 a distributor valve 32 which includes housing 34 provided with a rim 36 that extends forward and is in engagement with the rear face of coverl plate 25 with the housing being held in place by"'screws`"33 that extend through the rim and are threaded into reinforcing member 40 that is bonded to the inner face ofthe cover plate with the housing thereby formingV a distribution chamber 42 which extends over a portion of each of the manifold chambers 26, 28 and 30. Connected with housing 34 is conduit 44 which communicates with a source of suction such a vacuum pump (not shown) and is provided at its end with flange 46 which is attached to the valve housing by screws 48 and with communication with the interior of the housing being had through the opening 50.

Communication between manifold chambers 26, 28 and 30 and the interior of distributor valve housing 34 is had through openings 52, 54 and 56, respectively, that extend through cover plate 24. Control of communication between these manifold chambers and the valve housing through these openings is hadby means of side valve 58 which is in sliding overlying relation with the outer face of the cover plate 24, this valve being in the form of a plate that is slidably received in longitudinal recesses 60 (Fig. 5) formed in the horizontal extending portions of rim 36 of housing 34 and with abutment members 62 extending from the inner. face of the housing into sliding engagement with the valve plate so as to retain it juxtaposed to the cover plate in order that it will be capable of acting as a valve with relation to the openings extending through the cover plate.

Longitudinal movement of slide valve 58 within valve housing 34 is effected by means of valve stem 64 which extends laterally outward through the side of the valve chamber and has its inner end secured to the block 66 mounted on the valve. The valve has three operating positions and when in its outermost extreme position, which is indicated in Figure 1, only the central manifold chamber 26 is in communication with chamber 42 of the valve housing, while in its intermediate position manifold chambers 26 and 2S are in communication with the valve housing, and in its innermost position (Fig. 6)V all of the manifold chambers are in communication with the valve housing. To effect this result the valve plate (Fig. 7) is provided with openings 68 and 70 that are adapted to communicate with opening 52 in the cover plate; openings 72 and 74 that are adapted to corrimunicate with opening 54 in the cover plate; and opening v76 that is adapted to communicate with opening 56 in the cover plate. As indicated in Figure l, when the slide valve is in its outer position it is positioned to the right of opening S2 so that this opening is unobstructed and in communication with the valve housing while openings 54 and S6 are covered by the slide valve. When in its intermediate position opening 52 communicates with opening 68 in the slide valve and opening S4 communi- Acate's with opening 72 while opening 56 remains covered;

the'area covered b'y'ea'ch of these chambers progressively increases in this same manner and `because the spacing of passages 18 that communicate with the outermost chamber 30'are less than that of chambers 26 and 28 as well as because the passages 18 that are located at the upper central position of backing plate 14 and which communicate with chamber 30 are of larger diameter than the remaining passages in the backing plate with this being for the purpose of providing a greater force at the upper central portion of the sheet to hold it against the support since the sheet will tend to hang from this upper central portion. The chambers outwardly of the centermost chamber 26 are progressively larger in order to give a practical range to the` different areas of the face to which suction is applied and the closer spacing -of the openings 18 and groups of openings 12 communicating with the outermost manifold has been found to give better operating results.

When suction is being applied to chambers 26, 28 and 30 it is desirable for each of these chambers to have substantially the same degree of vacuum in order that the film sheet will be firmly and flatly held against the front of facing plate throughout the area of the sheet and to insure against the formation of wrinkles or pockets where the film is spaced from the facing plate. To achieve this result the effect of the progressive increase in Vtotal area of passages 18- communicating with the chambers more removed from the center must be cornpensated for. Therefore when chambers 26 and 28 are in communication with the valve housing the communication of chamber 26 with the housing must be more restricted than that of chamber 28. For this purpose ow restrictor 77 is positioned over the opening 68 in the slide valve with this flow restrictor being in the form of a iiexible or spring fiapper, as shown, secured at one end to the valve by rivets or screws 78. Thus when the valve-is in its intermediate position where openings 68 and 72 in the valve communicate with openings 52 and 5.4 respectively in the cover plate 24 communication of chamber 26 with the valve housing is effectively restricted with respect to communication of chamber 28 with the housing because of the resilient restrictor 77 with this restrictor being chosen so that the degree of suction in chambers 26 and 28 is substantially the same. In a like manner opening 70 and 74 in the slide valve have positioned over them leaf spring restrictor members 80 and 82, respectively, with these flow restrictors being effective to restrict communication of chambers 26 and 28 respectively with the valve housing when the valve is in its innermost position and with the restriction afforded by these members being such that the degree of vacuum in the manifold chambers 26, 28 and 30 is substantially the same when the valve is in this innermost position.

In order that an indication may be provided as to the proper positioning of the valve in its various operating positions'valve stern 64 is formed with three longitudinally spaced recesses 84, 86 and 8S which are adapted to successively receive spring pressed detent 90 which is provide/d in boss 92 on the side of the valve housing and with this detent being in the form of a spring biased ball retained within a capped bore as shown in Figure 4. When the valve is in its outermost postion detent 90 is received within recess 84 and suction is applied only to the central manifold chamber 26, which is suitable for use with small sizes of sheets; when the valve is in its intermediate position where suction is supplied to both chambers 26 and 28 detent 90 is received within recess 86 which is suitable for medium sizes of sheets; and when the valve is in its innermost position detent 90 is received within recess 88 and suction is applied to all three manifold chambers and accordingly to the entire area of the support for use with large sizes of sheets and for use with roll film. An additional indication of the position of the valve is provided by the markings L,

M and S on the rear of cover plate 24 and with which the end of valve stem 64 cooperates to indicate the area of the support to which suction is applied and accordingly the size sheet that may be employed, with these markings indicating small, medium and large.

The three overlying plates 10, 14 and 24 are secured together about their outer edges and at the location of partitions 22 in a uid tight manner by bolts 71 which are countersunk into facing plate 10 and extend through aligned bores provided in the facing plate 10, backing plate 14, and cover plate 24. Threaded on the outer end of each of these bolts is a nut 75 which when tightened down securely clamps the plates together. The plate 10 is preferably made of a plastic material such as phenol formaldehyde or plate 10 may be of such'a material, and a sealing cement is interposed between the plates prior to clamping the plates together by means of the bolts 71 and nuts 75.

In operation of the improved film support of this invention, the support is mounted in a vertical position so that the outer face of facing plate 10 is vertically disposed and against this outer face is positioned the flexible sheet of copy or photosensitive material which is to be supported and maintained flat by the support. When copy or cut film is being supported, valve 58 is operated so that the area of the facing member to which suction is applied corresponds as near as possible to the size of the sheet. When the sheet is of sufficiently small size so that it will lie within the bounds of central chamber 26, valve 58 is moved to its outermost position where the end of valve stem 64 is opposite the letter S (as shown in Figure l) and detent 90 is received within recess 84 in the'stem. In this position unrestricted communication of chamber 26 with valve housing 34 is had through opening 52. When the sheet is too large to lie within the bounds of chamber 28 slide valve 58 is moved to its intermediate position where the end of stem 64 is opposite the letter M and detent 90 is received within recess 86. In this position of the slide valve 58 manifold chamber 28 is in unrestricted communication with the valve housing 34 through opening 54 while communication of chamber 26 with the valve housing is restricted by How restrictor 77 and with the vacuum formed in chambers 26 and 28 being substantially the same even though the total area of passages 18 communicating with chamber 28 is substantially greater than that communicating with chamber 26. When a still larger sheet of material is being used so that it extends beyond the bounds of chamber 28 or when roll film is being used valve 58 is positioned in its innermost position with the end of valve stem 64 being opposite the letter L and detent 90 being received in recess 88. In this position (which is shown in Figure 6) the outermost chamber 30V is in unrestricted communication with valve housing' 34 through opening 56 while the communication of cham- V bers 26 and 28 with the valve housing is respectively' restricted by the ow restrictors and 82 which are: effective to produce a substantially equal degree of vacuum in all the chambers notwithstanding that the total area of passages 18 communicating with chamber 30 is greater than that communicating with chamber 28 which is in turn greater than that communicating with chamber 26.

Thus with the organization of the present invention the application of suction to the sheet support may be restricted to limited centrally located positions that are defined by a manifold arrangement and with the suction etfect in the compartments of the manifold being equalized. The resilient fiapper type restrictors tend to be automatic in their operation since as the pressure in the manifold chamber with which the restrictor is associated increases relative to that in the valve housing (i.e., the degree of vacuum in the chamber decreases) the restrictor moves to a less restricting positon resulting in decreasing the pressure in the chamber and accordingly increasing the.

7 degree of vacuum. therein. An increase in the degree of vacuum in themanifold chamberA above its desired valve hasv just the, opposite,y effect with the flow restrictor moving to a more restrictingposition.

The invention inits` broader aspects isnot limited to the4 specific mechanisms shown and described but departures maybe made therefrom, within the scope ofthe accompanying claims, without departing from the principles-of the invention and without sacrificing its chief advantages.

What-is claimed is:

l. A vacuum type-sheetvsupport comprising in combination a facing memberhaving a frontface adapted to receive. afleXiblesheet andL provided with groups of openings distributed thereover` for the application ofl suction to, said sheet, means overlyingthe back of said facing member and forming a manifold forthe application of suction to said groups of openings with said manifold havingy a` plurality of separate chambers that are internestedtand: that collectively effectively cover substantially the. entire area ofthe facing Amember. with individual openings being providedzin saidmeans and establishing communication between each group of openings and its overlying manifoldchamber` and with the` total area of said individual openings-communicating with the centermost chamber' beingI substantially less than that of the chamber surroundingsaid centermost chamber, a conduit for applyingsuction to the sheet support and a-distribution valve attherear ofv said meansto control the application of suction to the manifold' chambers through said conduit said valve beingin direct communicationfwith eachmanifold-chamber. and operativeY to selectively establish communication between the chambers and the conduit progressively outward .from the centermost chamber, said-valve including al owrestrictor restricting communication ofthe centermost chamber with said conduit relativeto thesurrounding chamber when both chambers are in communication with the.conduit withsaid restrictor being of suicient capacity to. generally compensate for the difference in total area-offsaid individual openings communicating with these, chambers so that the degree of vacuum in them is generally the. same.

2. In an organization of the. type described the combination of a., vertically disposed support member for verticallysupporting aexiblesheet of material in firm intimate contact therewith, said support member comprising a vertical facing plate provided with groups of openings distributed over itsarea, means at the back of -said plate forming. a. manifold;having a plurality of separate chambers one', of-` which. is generally. centrallydisposed with respect tothefacingplate. with the others disposed about, and-progressively outward of said central chamber andv with the.. chambers` collectively effectively covering substantially thetentire-area ofthesfacing plate, said means having individual. openings.k establishing communication between each group Aofaope'nings-and:its overlying-manifold chamber. with the-total area: of said individual openings, communicatingwith' each chamber-respectively increasing `withnthe distance ofthe chamber from the centermost, adistributor.valveffor controllingthe application of suction to said,;manifold including a housing adapted to be. connected to a-source of suction and mounted onV the rear of said manifold means said valve including a..slide valving member maintained in overlying valving relation with the back of the manifold means andfextending: over an area overlying aportion of'each separate chamber,y meansffory moving said valving member to andfromextreme operating positions, the back ofsaid manifold means havingopenings extending therethrough from the manifold chamber into said housing with said openings and ysaid valving-memberbeing arranged so that when thetvalvingmember .isin one Aextreme .position it is effectiveto bloclglatlleast all ofthe openings but the opening extending. fram thesentermost Chamber and when in .the

other; extrenregpcsfitcn is effective, to.. vpermit communi-,-

cation between all of the chambers; andV the housing through the openings, with said valving member successively moving from itsl blocking position of said openings from the inner chamber outwardly andinto its .blocking position from the outer chamber inwardly when moved to and from its extreme positions, and means operative to successively restrict communication of each cham ber inwardly of the outermost chamber communicating with the housing and relative to the outermost chamber as the valving member is successively moved from its blocking position with the restriction being suicient to generally compensate for the variationA in the` area of the individual openings-communicating with the several chambers so that each chamber will have more generally the same suction.

3. A vacuum type sheet supportl comprising'avertical facing plate provided with groups of openingsfdistributed over its area, a backing plate overlying the` backof said facing plate with individual openings extending through the backing plate from each group of openings, a cover plate covering the back of the backing plateand forming therewith a manifold for the application of suction to said groupstof openings, partitions disposed generally normal to the plane of the facing plate and dividing said manifold into a plurality of separate intcrnested chambers collectively etfectivelyextending over the area of the face covered by said groups of openings with the total area of said individual openings communicating with-each chamber progressively increasing from the. innermost chamber-outwardly, means for controlling the application of suction to said chambers-comprising a housing mounted on the rear of said cover plate adapted to bey connected with a source of vacuum, a slide valve in said housing and retained in overlying sliding relation with said cover plate, said valve extending over an area overlyingI aV portion of each separate chamber, means extending from said housing-and operative to move said valve to andl fromextreme positions, said cover plate having a-separate opening extending therethrough from each chamber into the-housing, said openings and valve being disposed softhat whenV saidvalve is in one-extreme position it overlies at least those openings in said cover plate communicating with the chambers outwardly of the centermost and is operative to selectively establishcommunication between these chambers and the housing through these openings progressively from the center chamber outwardly upon movement from said one extreme y position toward the other extreme position and fiexible leaf flow restrictors carried by said valve and progressively disposed over the openings through thecover-fplate as said valve is -moved from` said one extreme-position towardi the other extreme position to overlie all but the outermost opening through which communication is had for any particular setting ofthe valve thereby restricting communication of said-"inner chambers with the V,housing :relative-.tothe outer chambers communicating therewith.

4. The organization of -claim 3including'means'operai tive to-indicate the selective positioning of "the valve.

5; A- vacuum type sheet support comprisingI in combination a facing member having afront face` adapted to receive a iiexible sheet and provided with groups of openings distributed thercover for theapplication of suction to said sheet, means overlying the back of said facing member and forming a manifold for the application of suction to said groupsy of openings, with said manifold having ya plurality of separate chambers that are internested and that collectively effectively cover substantially the entire mea of the facing-member with the area of operative to selectively establish a communication between the manifold chambers and the conduit progressively outward `from the centermost chamber when moved in one direction and preventing7 such communication progressively inward rfrom the outermost chamber when moved in the other direction, and ow restrictors progressively moved in response to movement of the valve member into restricting positions restricting communication with said conduit of the manifold chambers inward of the outermost chamber communicating with the conduit, said restriction being such as to generally compen- 5 several chambers will be generally the same.

References Cited in the le of this patent UNITED STATES PATENTS 2,814,233 Anander Nov. 26, 1957

Images