US3054325A - Projection screen - Google Patents

Description

p 1962 D. CROCKWELL 3,054,325

PROJECTION SCREEN I 1 a; W {a m r I .2 4 M '4 FIG.!

Ni/J22 :0 I I6 FIGZ 4%: .8 BY Ziiifii ATTORNEY Sept. 18, 1962 0. CROCKWELL 3,054,325

PROJECTION SCREEN Filed Aug. 22, 1960 I 2 Sheets-Sheet 2 I t INVENTOR. DOUGLASSCROCKWELL 28 18 BY W ATTORNEY United States Pater 3,054,325 PROJECTION SCREEN Douglass Crockwell, P.O. Box 221, Glens Falls, N.Y. Filed Aug. 22, 1960, Ser. No. 50,914 1 Claim. (Cl. 8828.91)

The present invention relates to new and useful improvements in structural refinements in a foldable projection screen and is directed more particularly to the provision of a collapsible screen which can be readily extended to operative position. Same has general utility in the arts and contemplates means for adapting it to be folded, when not in use, so as to occupy a minimum of space.

The existing practice in the trade, as exemplified by the known prior art on portable projection screens, has been to employ a flexible reflective sheet rolled up within a housing on a spring roller, which sheet is adapted to be unrolled from the housing to extended operative position. Such screens all have the certain obvious objection that the sheet surface, which is usually silver coated or beaded, is extremely sensitive to the rolling action, is susceptible to damage by abrasion and scratches, and is easily marked by the coacting rollers, all of which serve to deform the surface, which deformations are readily visible when images are projected thereon. These prior constructions are thus attended with certain serious disadvantages and limitations which have militated against their more general adoption.

In contradistinction, I have discovered that all of these disadvantages are overcome and new advantages accrue when and as the device of my invention is used.

I have devised a novel means whereby these aforestated difficulties and objections are overcome. I accomplish same by the provision of a device which obviates the screen rolling action ab initio.

With further reference to present day trends in the techniques of projecting pictures, it is acknowledged that the wide screen, where the width of the projected picture is greater than its height, has become increasingly popular so as to create a demand for screens of such character, the conventional rolled screens being obviously unsatisfactory because of the excessive widths involved.

The apparatus of my invention answers this need and additionally serves a useful purpose in connection with the projection of pictures of the panoramic type.

Additionally, I provide a construction by means of which the curved surface, so desirable in present day methods of projection, is easily attainable.

Herein, I provide a screen of extreme width which may be folded in order to reduce its width, when in the storage or shipping state, and wherein the screen surface, whether it be of the beaded or silver coated type, is protected against being sharply bent or folded.

The conventionally rolled screens do not lend themselves to being curved in manner found to be most desirable in the case of screens of the wide type where, because of their unusual width, the radius of curvature is preferentially equal to or substantially equal to the distance between the screen and projector Failing to so curve the screen, it is known that the ends of a projected picture and the center of said projected picture do not normally appear in equal brightness.

By means of the construction hereof, the so-called wrap-around effect is achieved more readily, same being the very essence of panoramic quality.

The invention resides in the particular construction, arrangement, combination, and relationship of the var ious elements, components and instrumentalities of a projection screen as exemplified in the detailed disclosure "ice hereinafter set forth wherein the objects of the invention, as defined in the paragraphs below, will be apparent.

It is a principal object of the invention to provide an inventively novel and improved construction of the type in which a screen proper is mounted upon a framework which may be extended to open, viewing position, and may be folded to form a compact unit which is easily transported and stored.

Another chief object of the invention is to construct a projection screen of the general character indicated wherein the primary framework is comprised of individual panels articulately connected by novelly geared hinges which allow the screen to be folded without objectionable binding or pinching of the reflective component when the apparatus is closed.

Another feature resides in the provision of a projection screen which, when extended, is suitably curved for the reception of wide screen projection.

In prior art constructions, it has been common to lace the screen to its frame. In the case of a curved screen however, it is difiicult if not impossible to lace the screen to its frame and have it remain flat and smooth, there being an inherent tendency for the reflective component to assume a totally undesirable reverse vertical curvature under tension.

The screen hereof is mounted on a stiff backing panel which is slightly curved. The panels are of such configuration as to maintain their vertical straightness, while at the same time, they offer the desired bend or curvature in a horizontal direction.

Stated otherwise, the present invention contemplates the provision of a multi-section projector screen having a suitably curved projection surface when in the open view ing position, and which may be folded in such manner that each of the individual panels extends in substantially parallel and overlapping position as to the others.

In addition to the practical advantages which (I have herein before ascribed to my novel projection screen, it will be observable that another chief featureresides in the fact that the screen is simple and compact in construction, and well adapted to withstand the usage to which a projection screen is ordinarily subjected, convenience of arrangement of parts and extreme compactness, both conducive toward the provision of a screen of small proportions, and ruggedness and durability, being further desirable features that have been borne in mind in the production and development of the present invention.

The invention embraces broadly the concept of a screen of appropriate material offering a reflective surface of any desired typewhich is mounted in a framework which can be extended to display position and which can be folded so as to occupy a minimum amount of space.

The framework is so designed and a screen so mounted thereon that, when folded and stored, the reflective sheet is protected and is bent with a relatively large radius of curvature so as not to be marked or otherwise damaged, regardless of for how long a period of time the structure is held in the storage position.

As a further refinement, the framework envisions a central frame section having an outer frame section hingedly connected to each of the sides thereof, the flexible reflective sheet being mounted between and fixed to the upper and lower rails of the respective central and outer frame sections. Y

The outer frame sections may be movable between positions in line with the central frame section (when in the.

herein before ascribed to my novel projection screen, it will be observable that another chief feature of the invention resides in the fact that the reflective sheet is secured to the frame sections except in the areas immediately adjacent the hinged connections between said frame sections so that, when in the folded condition, the reflective sheet assumes gentle curvatures instead of sharp folds along any specific fold lines. Conversely, when in the unfolded condition, the reflective sheet is capable of assuming a smooth uniformly curved configuration from end to end.

Other of the chief objects and purposes hereof are to provide advantageous structural and operational features in a device of the class to which reference has been made so as to provide an apparatus having the following inherent meritorious characteristics; first, a simplicity in construction and compactness of design and therefore an adaptability to economical manufacture; second, a uniqueness in engineering design of coacting parts wherefor the components are coordinated for facile assembly; third, a susceptibility to easy installation with respect to the various purposes to which it is intended; fourth, a high degree of efficiency and dependability in its operational use; fifth, the provision of a construction which is well adapted to withstand the usage to which a projection screen is ordinarily subjected and sixth, the provision of such other improvements in and relating to projection screens of the type above referred to as are hereinafter described and claimed.

Further objects hereof are to provide a projection screen conformable to the desiderata of the preceding paragraph and offering specific improvements in the various operating instrumentalities comprising same, which themselves are minimum in number, so that it is simple and compact in its design, distinctive in its appearance, practical in its value, durable in its organization, reliable in its operation, and efficient in its use.

The invention is not limited to the structural details or arrangement of parts here shown since a projection screen construction embodying said invention may take various forms, it being susceptible of various modifications and alternative constructions. Said physical embodiment delineated is only indicative of but one of the various ways, albeit the preferred exemplification, in which the principles of the invention may be employed and in which the component parts may be combined and arranged. Same is submitted as one best known embodiment of the invention in accordance with the patent statutes and is given with a view to illustrating and explaining the precise nature of the principles of the invention and their embodiment for practical use, in order that others skilled in the art may be enabled to adapt and modify them in numerous embodiments, variations and modifications, each as may be best adapted to the conditions of any particular use.

I do not thereby intend to limit the invention to the specific form disclosed, but rather intend to embrace herein all modifications, variations, alternative constructions, and equivalents falling within the spirit and scope of the invention and within the meaning and purview and range of equivalency of this disclosure.

The above named objects I accomplish by means of such structure as will fully appear from a perusal of the description which follows and the illustrations in the accompanying drawings, where like characters of reference are employed to designate like or corresponding parts throughout the several views and in which:

FIG. 1 is a view in perspective showing the screen in open, extended position;

FIG. 2 is a view in perspective showing the screen of FIG. 1 in its closed, folded position;

FIG. 3 is an enlarged top plan view of a geared hinge member of the apparatus of the invention;

FIG. 4 is a front elevational view of the hinge member shown in FIG. 3; and

FIG. 5 is a partial elevational view of the rear surface of the screen of FIG. 1.

With continued reference now to the drawings, which illustrate a typical and preferred embodiment of the invention for the purpose of disclosure and forms a part of this specification, I have shown in FIG. 1 a multi-section projection screen generally indicated by the numeral 2 and comprised of an elongated reflection screen 4, mounted upon individual frames 6, 8 and 10 the adjacent frames being articulated as by hinge members 12 and the whole being supported upwardly of a base or floor as by legs 14.

Each of the frames 6, 8 and 10 is identical in size and configuration and is formed from spaced, upright wooden support members 16 connected by curved metal top and bottom rails 18 and reinforced by a preshaped arcuately formed backing board 20 of suitable material mounted upon said support members 16 and top and bottom rails 18.

The frames 6, 8 and 10 are articulated as by the geared hinge members 12. Hinges 12 are affixed to the upper and lower extremities of each of the wooden support members 16 of the frame 8 and are affixed to the corresponding extremity of the adjacent wooden support member 16 of the respective frame 6 or 10.

As illustrated in FIGS. 3 and 4, each of the hinges 12 is comprised of a pair of base plates 22 and 24, which plates are provided with circular apertures 26 through which screws 28 may be passed to secure the hinge to the respective support member 16 of one of the frames.

Meshing quarter gears 30 and 32 are fixed to the forward edges of the base plates 22 and 24 respectively as by welding or the like.

A top plate 34 is superposed upon gears 30 and 32 and is fixed to the bottom plates 22 and 24 as by the threaded stems or studs 36 and the nuts 38. Said stems 36 pass through, but are not rotatable within, suitable apertures in the base members 22 and 24.

Appropriately aligned openings 40 are provided in the top plate 34 whereby access to the screws 28 may be had when the hinges 12 are being installed or removed.

As the screen 2 is folded, the gears 30 and 32 of the hinges 12 are meshed and maintain the support members 16 to which the hinges are fixed in spaced relationship throughout the folding and/or unfolding operations, preventing any binding or pinching of said support members. The geared hinge members effectuate a fixed radial swing of the panels relative to each other.

Adjustment bolts 42 pass longitudinally through the inner wooden support members 16 of the frames 6 and 10. By rotation of said adjustment bolts within the nuts 44 which are imbedded in the members 16, the frames may be adjusted to achieve maximum tautness of the screen 4 on the said frames.

Locking members 46 are centrally aflixed to each of the support members 16 of the frame 8 and to the adjacent support members of the frames 6 and 10 whereby the screen 2 may be locked in the open or extended position.

Hinges 48 are fixed to the lower extremities of each of the support members 16 of the central frame 8 to which the upper extremities of the legs 14 may be affixed. Mounted in this manner upon the hinges 48, said legs 14 may be collapsed and folded against the frame 8 when the structure is being transported or stored.

The screen proper is in the form of a thin, flexible sheet 4 having a coating of appropriate reflective material applied to its outer' surface. Said screen 4 is stretched tautly over, and is fixed by a suitable adhesive to the top and bottom rails 18 of the panels 6, 8 and 10, and to the endmost support members 16 of the panels 6 and 10. Adhesive is not applied to the support members 16 of the panel 8, nor to the adjacent support members of the panels 6 and 10, to the end that the projection screen 2 may be folded without tearing or distorting the flexible sheet 4. These non-adhering portions of the screen allow member 4 to pull tight when the screen is opened.

In the drawings areas A and B indicate those surfaces to which adhesive has not been applied.

It will be appreciated that the screen hereof, when folded takes up a minimum amount of space, the outer frame sections on either side of the central frame section are adapted to extend substantially parallel to and alongside one another by means of the articulate connections therebetween.

In accordance with the provisions of the patent statutes, I have illustrated and described the principle of operation of my invention together with the apparatus which I now believe to represent the best and preferred embodiment thereof, but desire to have it understood that the apparatus illustrated and described is only exemplary and that numerous modifications and rearrangements may be made therein without departing from the essence of the invention.

Without further analysis, the foregoing is intended to so fully reveal the gist of my invention and its construction and operation that others can, by applying current knowledge, readily adapt it for various applications without omitting features which, from the standpoint of prior art, fairly constitute essential characteristics of its generic and/or specific aspects. The substitution of equivalents and other changes, modifications and alterations as circumstances may suggest or render expedient, are contemplated since the invention is susceptible of such without departing from its real spirit or underlying principles. Stated otherwise, it is not desired to limit this invention to the exact construction shown and described as the objects hereof may be attained by the use of constructions different in certain respects from that disclosed.

The protection which is sought for this invention is covered by the language of the specification and the spirit represented thereby and same is limited only by the prior art and the scope of the appended claim.

What is claimed as new and useful is:

A multi-section foldable projection screen comprising, a trio of substantially rigid frame sections each formed from spaced upright supports connected by curved top and bottom rails and reinforced by a pre-shaped backing board framed within the supports and rails, hinge means for articulately securing the adjacent frame sections of said trio thereof to each other for the movement thereof relatively between closed positions in overlapping substantially parallel disposition and open positions in extended curving disposition making obtuse angles less than relative to each other, each said hinge means including a pair of base plates secured to the respective adjacent upright supports of the frame sections of said trio thereof and a pair of quarter gears fixed to each of the base plates of the pair and being meshable with each other for maintaining the respective adjacent upright supports in spaced relation throughout the folding and unfolding operations, and an elongated reflective sheet overlying the frame sections of said trio thereof and adhesively secured to the top and bottom rails of each of the frame sections of said trio thereof and being adhesively secured to certain of said upright supports whereby when said sections are opened said sheet is held in extended smoothly curved condition and when said sections are closed said screen may be folded without distorting said sheet and without binding between adjacent frame sections of said trio thereof.

Messinger Aug. 7, 1900 Hurley Mar. 25, 1958

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