US1901963A - Support and stretching mechanism for motion picture screens - Google Patents

Description

2 Sheets-Sheet l IN VEN TOR.

afi ATTOR EYS.

P. HANSEN Filed March 6, 1951 v N d076 QWW W Q in SUPPORT AND STRETCHING MECHANISM FOR MOTION PICTURE SCREENS March 21, 1933.-

March 21, 1933. J. P. HANSEN 1,901,

SUPPORT AND S'IRETCI'IIIflC MECHANISM FOR MOTION PICTURE SCREENS Filed March 6, 1931 2 Sheets-Sheet 2 INVENTOR. MW

w i Ma 3K Patented Mar. 21, 1933 Y v UNITED STATES PATENT OFFICE JOHN P. HANSEN, F ELMHUBST, NEW YORK Application filed larch 6,

' My invention relates to an improved support and stretching mechanism for motion picture screens.

'At the present time motion picture screens are supported on frame-Work to which they are laced by means of ropes or cables. When it is desired to stretch screens thus supported all the stretching must be done by tightening upon the ropes. For this reason it is neces- 0 sary for workmen to climb the frame-work for the purpose of lacing the screen to the support and also when tightening the ropes in stretching the screenwith the ever constant danger of workmen falling.

It-is one of the objects of my invention to provide a combined support and stretcher for motion picture screens whereby the securing of the screen to the support and all stretching of the screen is accomplished by the workmen on the stage without the necessity or danger of climbing the frame-work.

Another object of my invention is the provision of a device wherebythe installing and stretching of the screen is accomplished with comparative ease and a considerable saving in time and labor.

Further objects of my invention will be manifest from the following description and the accompanying drawings in which Fig. 1 is an elevational view of my improved device;

Fig. 2 is a sectional View on line 2-2 of Fig. 1

Fig. 3 is a sectional view on line 3-3 of Fi 1;

Fig. 4 is a sectional view on line 44 of Fig. 1;

Fig. 5 is an enlarged view of the hoisting mechanism, and

Fig. 6 is a sectional view showing a modified form of sliding hook for the screen.

Referring to the drawings in detail 1 designates a stage on which rests supporting lattice frame-work comprising stationary vertical posts 2 and 3 and stationary overhead beam 4. A movable horizontal frame 5 is suspended from the overhead beam 4 by means of ropes 6 secured to the frame 5 and passing over a plurality of pulleys 7 secured to the overhead beam 4 and thence to the side of the 1931. Serial No. 520,736.

frame-work and over a pulley. 8 Where-the ropes are secured to a coupler 9. The coupler 9 has one end of a rope 10 secured thereto, the other end being secured wound about a drum or Windlass 11. The Windlass 11 is mounted upon a bracket 12 secured to the vertical post 3 and is adapted to be rotated by means of a crank handle 13 through gears 14 and15, a pawl 16 and ratchet 17 being provided to prevent the unwinding ofthe rope.

The movable frame 5 is in the form of a horizontally extending box having a plurality of covers 18 hinged thereto for convenience of accessibility and is provided at each of its extremities with rollers 19 and 20 which are adapted to ride on the outside of stationary vertical boxes 21 and 22 respectively rigidly secured to the vertical posts 2 and 3 respectively of the frame-work by means of bars or brackets 23.

Each of the vertical boxes 21 and 22 and the mechanism enclosed in each is similar hence only one of these will be herein described.

Within each of the vertical boxes 21 and 22 a longitudinal shaft 24 is provided having a beveled gear 25 at its lower extremity in engagement with another beveled gear 26 on crank shaft 27, which shaft is adapted to be rotated by means of a crank handle 28. On this shaft 27 there is also provided a pawl and ratchet arrangement 29 for locking the same against reverse rotation. The longitudinal shaft 24 is provided also with a plurality of spaced gears 30 adapted to engage a corresponding number of racks 31 which are mounted for lateral movement within the box and carry a vertical bar 32. This bar 32 may be in the form of a channel having a longitudinal opening or slot 33 in one wall thereof adapted to receive sliding hooks 34 which may be either in the form shown in Fig. 3 or that shown in Fig. 6, these hooks being adapted to slide vertically in the channel as will be hereinafter explained.

The horizontal movable frame 5 is pro vided with a bar 35 which extends longitudinally thereof and has a plurality of hooks 36 to and adapted to be pivotally secured thereto by. means of 36 by passing grommets 13 in the screen over said hooks. The frame 5 is then hoisted by rotating the crank handle 13 and as the frame 7 is being raised the grommets in the vertical prising vertically extending edges or sides of the screen are secured progressively in order to their respective hooks 34; on the vertical bars 32 until the screen has been completely raised andall of the grommets have been attached. The grommets along the lower edgeof the screen are then secured to the hooks ll on the bar 40.

The screen is now in position to be stretched and vertical stretching is accomplished by continuing the rotation of the crank handle 13. Transverse stretching is accomplished by rotation of the crank handles 28 upon rotation of which it will be obvious that the racks 31 will be moved laterally, carrying with them the Vertical bars at to which the screen is secured as above pointed out.

It will be seen from the foregoing, therefore,that I have provided a screen supporting and stretching apparatus so constructed and arranged thatall mounting and stretching of the screen can be done from the stage thereby, as above pointed out, eliminating the necessity of the workmen climbing the frame-work and running the risk of falling. It will be appreciated also that a more uniform stretching of the screen is obtaine than by the use of prior apparatus, thus insuring a smooth, taut screen which is exceedingl desirable in motion picture projection. I v

It is to be understood that I do not wish to be limited to the precise structure herein illustrated and described inasmuch as various modifications may be made therein without departing from the spirit and scope of my invention.

What I claim is: a

1. A device of the class described combars, vertically sliding hooks on said bars for securing a motion picture screen thereto, and means for moving said bars laterally to stretch said screen.

2. A device of the class described com;- prising a pair of vertical channel members, hooks carried by and movable lengthwise of said channel members, a motion picture screen carried by said hooks, means for able bar withineach moving said channel members laterally to stretch said screen.

3. In a device of the class described the combination of vertical bars, vertically sliding hooks on said bars for attaching the side edges of a motion picture screen thereto, means for moving said bars laterally to effect lateral stretching'bf the screen, a horizontally extending bar, means for attaching the upper edge of a motion picture screen thereto, said last-mentioned bar being movable vertically with respect to said vertically extending bars to effect vertical stretching of the screen.

4. A' device ofthe class described comprising vertically extending bars, means movable longitudinally of said vertically extending bars for securing the side edges of a motion picture screen thereto, means for moving said bars to stretch the screen laterally, a horizontally extending bar, means for securing the upper edge of the motion picture screen thereto, and meansfor raisin g said bar to stretch the screen vertically.

5. A device of the class described comprising in combination a pair of stationary vertically extending. housings, a laterally movof said housings, means carried by each bar for attachingthe side edges of a motion picture screen I thereto, means for adjusting said bar laterally'to effect lateral stretching of the screen, each of said housings being provided in the wall ad jacent the edge of the screen with a continuous slot for the accommodation of the edge of the screen upon lateral stretching of the screen, i

This specification signed this 13th day of February, 1931,

. JOHN P. HANSEN.

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