US2093060A - Construction of metal cinema screens - Google Patents

Description

Sept. 14,1937. D TURNER 2,093,060

vCONSTRUCTION'0E METAL CINEMA SCREENS Filed July 18, 1955 o o 00D GOO ceac@ 00009.

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ATTopA/y Patented Sept. 1.4, 1937 PATENT OFFICE CONSTRUCTION OF METAL CINEMA SCREENS David Turner, Gloucester Gate, England Application July 18,

1935, Serial No. 32,079

In Great Britain July 19, 1934 1 Claim.

This invention relates to improvements in the construction of cinema screens.

Heretofore metal screens have not been satisfactory because they cannot be made seamless of the desired size and consequently lapped seams are employed which lapped seams are visible in practice and set up resonance. Further such metal screens easily buckle and give off a drumming when sound is passing through the perforations in the screen from the loud speakers placed at the rear of the screen.

The object of this invention is to overcome these defects and to provide a perforated metal screen which will give a bright and stereoscopic effect to pictures projected thereon and which will have little or no resonance.

With this and other objects in view the invention consists in forming a screen from a number of sections or sheets of perforated metal, the said sheets or sections being butted together edge to edge and secured to a wood or like framework, the edges of the sheets being secured to the wood or like framing by nails, screws, rivets or by other suitable means, the heads of the said nails or other means being embedded in the screen material so as to provide a flush surface. It will be understood that the Wood or like framework behind the butted seams will avoid the setting up of resonance and have a deadening or damping effect. Further the nails or other securing means passing into the wood will tend to earth or conduct away any resonance which may be set up. The perforated sheet material may be zinc or other metal in which lead is an alloy or forms part thereof or the sheet material may be of steel coated or covered with, for instance, another metal. The covering may be spelter, lead, copper, tin or white metal. Alternatively, the metal sheet may be formed of a mixture of metals or alloys.

One form of the invention will now be described With reference to the accompanying drawing in which:-

Figure l is a part front elevation of a screen with parts broken away.

Figure 2 is a part vertical section.

Figure 3 is a perspective view of part of the framework, and

Figure 4 is a detail showing the butting edges of two sheets and the securing means.

As shown the improved screen is formed of a number'of sheets a of perforated zinc or other metal which are laid edge to edge and secured to the frame or structure b. The frame or structure b is formed of vertical members c and horizontal members d so as to provide openings e of slightly less area than the area of the sheets a. Thus the sheets a can be readily secured to the members c and d by small nails, screws, bolts or rivets f formed with flat heads which when driven home automatically sink slightly into the lead alloy and form a homogeneous whole. The frame or structure b may be of any size for instance when a screen of 20 feet by 16 feet is constructed, the struts or members c and d are arranged to provide apertures of slightly less than six feet by three feet so as to enable sheets of this size to be butted against one another edge to edge and secured to the struts. 'I'he struts or members c .and d of the frame b may be mortlced and tenoned together as shown as g in Figure 3 or they may be otherwise secured. The struts or members c and d are further secured by screws or bolts. If desired, the seams h may be filled with a suitable filling material such as solder, lead, putty or other suitable material. The screen when formed may be enamelled, painted or otherwise treated on one or both sides, the front side for the purpose of portraying the image from the lm and the rear side to prevent rust and also to prevent the sound waves touching the raw metal and setting up resonance. The holes i in the metal sheets a may be of any size and of any shape. It is preferable within certain limitations to make the holes i as large as possible and the sheets a of thick material so as to give a greater stereoscopic and brighter effect and a more perfect side picture due to the sides of the holes. Preferably the depth of the holes should exceed I@ of an inch. 1f desired, the struts c and d of the framework may be apertured to coincide with the holes in the sheets or the struts may be grooved, corrugated or otherwise formed to permit of a passage of air through the perforations in the screen so as to prevent discolouration due to dirt or fumes. Further the struts c and d may be of any shape in cross section for instance, they may be of triangular, circular, hexagonal or octagonal shape. The holes or perforations i in the screen may be round or of triangular, square or hexagonal shape and the butting edges h of the sheets may be chamfered, toothed, serrated or constructed to interengage in any suitable manner. Angle irons or other reinforcements may be provided at the corners or other parts of the screen to give rigidity and eye bolts or the like may be provided for flying or raising the screen.

It will be seen that I have provided a screen built up of a number of units which when painted or otherwise treated Will give the eiect of a single sheet possessing a flat surface. Further the screen Will be substantially reproof as the frame is preferably constructed of oak or teak, Whilst the main or other parts are of metal.

What I claim is:-

A cinema screen made up of an open frame including Vertical struts and cross bars, perforated metal sheets secured on the cross bars and Vertical struts with their edges in abutting relation and with the sheets in the same plane, the uprights and cross bars being formed with openings in registry with the openings in those portions of the metal sheets resting on said struts and cross bars in order to permit free passage of air through the perforations in the metal sheets to avoid the accumulation of dust or dirt therein, the metal sheets being of such thickness that the edges of the openings therein Will eX- ceed 1/64 of an inch in thickness, whereby to produce a greater stereoscopic and brighter effect and a more perfect size picture due to the size of 10 the holes.

DAVID TURNER.

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