US1728739A

US1728739A - Moving-picture projector

Info

Publication number: US1728739A
Authority: US
Publication date: 1929-09-17
Anticipated expiration: 1946-09-17

Description

p 1929. F. SPAULDING IOVING PICTURE PROJECTOR Filed April 23, 1927 2 Sheets-Sheet Sept. 17, 1929. F. SPAULDING 1,728,739

MOVING PICTURE PROJECTOR Filed April 23, 1927 2 Sheets-Sheet 2 Jmnkhn E cu1d1nq @gu Q/aa/ h 017 W Patented Sept. 17, 1929 UNITED STATES PATENT OFFICE FRANKLIN S PAULDIN G, OF CHICAGO, ILLINOIS MOVING-PICTURE PROJECTOR Application filed April 23,

Great difficulty is experienced in the operation of moving picture projectors in providing proper safe-guards against the destruction of the machines, as well as the film, and

damage to the projecting room, from fire caused by a stopping of the film in the-path of the light. Attempts have been made to overcome this hazardby providinga dowser which the operator is supposed to drop into the 10 path of the light when the film stops for any reason, but operators frequently become careless and as a result fire results. Realizing the fire hazards connected with moving picture projectors, practically every city has enacted an ordinance requiring the installation of fire guards at the point the film enters the magazine and in the past this fire guard has consisted of a-pair of rollers and a larger intermediate roller, between which the film passes, the rollers being supposed to snuff out the fire and prevent its entering the magazines. However, these guards have been found wholly inadequate and as a result the machines are frequently completely destroyed by fire and the. underwriters laboratory and projector manufacturers have been making diligent research to produce a fire guard which will effectively prevent the entrance of fire into either of the magazines to thus con- 3 fine it entirely to the short length of film within the feed mechanismhousing.

It is, therefore, an object of this invention to provide positive means operable instantly upon the occurrence of fire within the feeding mechanism housing of the projector to absolutely disconnect or cut-ofi' the magazine from further communication therewith to thus confine the fire entirely within the feeding mechanism housing and prevent its reaching 4 the magazine. I

The standard type of moving picture projector has the film fed from the upper magazine by a constantly moving member and guided into the lower-magazine by a con- 4 n 5 stantly moving member, there being an intermittently operated feed member for moving the film in intermittent steps equal to the length of one picture, the film having loops therein at each side of the lens to accom- 1927. Serial N0. 186,066.

tion has as another object" the mounting of fusible or flammable means mounted juxtaposed each loop in the film'and operable upon the occurrence of fire to release the mechanism for positively shutting ofi the magazines from the feeding mechanism housing.

A further object of thisinvention resides in the provision ofmeans for severing the film at its point of egress from or ingress to the magazines substantially instantly upon the occurrence of fire within the feedingmechanism housing to entirely confine the fire within the mechanism housing. p

A further object of this invention resides in the provision of improved means operable substantially instantly upon the occurrrence of fire within the feeding mechanism housing to sever the film at the magazines and close the film passages thereto to absolutely .1- disconnect the magazines from the housin and prevent the spreading of fire.

A still further object of this invention is to provide an improved arrangement of the character described which may be readily applied to projectors now in use or to projectors at the time of their manufacture and which is capable of production at a very low cost.

With the above and other objects in view which will appear as the description proceeds, my invention resides in the novel construction, combination and arrangement of parts substantially hereinafter described and more particularly defined by the ap-. pended claims, it being understood that such changes in the precise embodiment of the hereindisclosed invention may be made as come within the scope of the claims.

In the accompanying drawings, I have illustrated several complete examples of the physical embodiment of my invention constructed according to-thc best modes I have so far devised for the practical application of the principles thereof, and in which:

Figure 1 is a view, partly in section and partly in side elevation, of a projector film feeding mechanism, mechanism protecting housing and the film magazines communicating with the upper and lower ends of the housing;

Figure 2 is a fragmentary view, partly in section and partly in top elevation, illustrating one of my improved film guards as applied to the topmost magazine, said view being taken through Figure 1 on the plane of the line 22;

Figure 3 is a view in vertical section taken through Figure 2 on the plane of the line 33;

Figure 4 is a view, partly in section and partly in elevation, taken through Figure 3 on the plane of the line 44;

Figure 5 is a view similar to Figure 4 of a slightly modified form of my invention, and

Figure 6 is a view, partly in section and partly in elevation, taken through Figure 5 on the plane of the line 6-6.

Referring now more particularly to the accom anying drawings, in which like numerals esignate like parts throughout the several views, 5 designates a film feeding mechanism housing having an upper magazine 6 mounted on its top and a lower magazine 7 at its lower end, there being an opening 8 in the rear wall of the housing through which the light 9 from a lamp housing, not shown, extends to pass through the film 10 and a lens 11 to project the picture of the film on the screen in the usual manner.

Each magazine is of substantially drum shape having a hinged door 12 and a reel 13 therein about which the film is wound, the film running from the magazine 6 through the mechanism housing to the magazine 7 and being fed intermittently past the opening 8 by an intermittent feed Sprocket 14, constant feed sprockets 15 and 16 being located adjacent the upper and lower magazines, respectively, in approximate alignment with the apertures or slots 17 communicating with the magazines and through which the film passes. As is customary in constructions of this type the

sprockets

14, 15 and 16 are operated from a hand crank 18 or else are motor driven and the film forms loops 19 at a point between the sprocket 15 and the outer end of a guide 20 through which the film passes over the aperture 8 and between the sprocket 14 and the sprocket 16, the loops compensating for the intermittent movement given the film in its passage across the opening 8 and permitting the constant rotation of the film reels.

Mounted adjacent each aperture 17 are a pair of complementary rollers 21 arranged with their axes in substantially vertical alignment and a lower roller 22 having its periphery extended between the peripheries of the small rollers, the film passing between the rollers in the manner illustrated in Figure 1. This construction constitutes what has heretofore been utilize-d as a fire guard, although actual experience has proven the inadequacy of this arrangement to prevent spreading of fire into the magazines with the resulting disastrous results. Therefore, this invention contemplates the provision of positive i'ncans at the point the magazine communicates with the feed mechanism housing for positively preventing the spreading of fire into the magazines from the feed mechanism housing, while the old fire guard consisting of the rollers may be entirely eliminated, inasmuch as it forms no part of this invention, I found it practical, especially when equipping an old projector with my improved invention, not to remove the old fire gun-.rd.

My invention conten'iplates the provision of two devices mounted each one juxtaposed to the point each magazine communicates with the feed mechanism housing and inasmuch as the construction and o )eration of both are identical, with the exception that they are reversed with respect to each other, due to the fact that one is at the top of a magazine and the other at the lower end,,the description will be confined to a single device, viz: that of the upper magazine and the numerals applied thereto are likewise applied to the device mounted in the lower magazine. Secured in the magazine at its end adjacent the mechanism housing is a member 23, preferably formed b Y die castin and havin a air of depending ribs or

flanges

24 and 25 conforming with the curvature of the magazine wall and connected by a pair of intermediate spaced transverse ribs 26 located at opposite sides of the film opening 17 to provide a passage through which the film passes. The top of the member 23 is channeled longitudinally from one end to a point on the opposite side of the film passage to provide a slide for a mo able blade 27, the loading or cutting edge 28 of which is diagonally disposed to correspond with the diagonally disposed inner end 30 of the Hat portion of member 23 opposite the channel so that when the movable blade is released, as later described, its edge 28 forms a seal with shoulder 30.

The blade 27 is slidably mounted between a rib 31 and a shoulder 32 extending throughout the length of the channel portion of member 23 and a plate 33 extending over the member 29 for its entire length and secured thereto by counter-sunk taper head screws or other means 34. An aperture 35 is formed in plate 33 in register with the passage between the ribs 26 and the film opening 17 in the'lower portion of the magazine so that the film may pass from the magazine and a slot 35', see Figure 2, extends from the aperture to the edge of the plate to permit the insertion of the film. The movable blade has a snug but sliding fit with its under surface so that its edge 28 and the edge 36 of the aperture 35 shear the film 1O therebetween as the blade closes thereover. The blade 27 is freely slidably guided against jamming by vertical side walls 37 and is normally yieldably urged into the path ofthe film by a contractile spring 38 mounted within the channel 39 formed between the rib 31 and one vertical side wall and having one end connected with the movable blade at 40 and its other end connected with the member 23 at 41, readily releasable means being provided for securing the blade in its retracted position illustrated in Figure 2 with the spring 38 under tension.

The blade 27 has a medial longitudinally extending slot 42 with its inner end slightly enlarged to form a locking recess 43 into which the end 44 of a locking cam 45 is engageable to hold the blade against its spring, the cam being mounted within the slot 42 and fixed to the upper end of a cam shaft 46 journaled in a tubular mounting stud 47 which serves to secure the member 23 in the magazine. The mounting stud 47 is externally threaded and has a flange or head 48 on its upper end seated within a recess 49 in the member 23 and being held in the recess by a jam nut 50, as illustrated in Figure 3, the lower end'of the stud passing through apertures in the magazine and frame 51 of thefeeding mechanigm housing and being secured thereto by a nut 52. A lateral bracket arm 53 is secured to the lower end. of the tubular mounting stud by jam nuts 54 and an arm or lever 55 is secured to the end of the cam shaft 46 projected beyond the lower end of stud 47, the

arms

53 and 55 having pins or studs 56 connected by a fusible or flammable element 57, to be later described.

When the blade 27 is in its position illustrated in Figure 2 and the cam shaft rotated to hold it in such position, the tendency of the spring to move the blade over the film passage likewise tends to rotate the cam shaft through its locking cam in a clockwise direction tending to move the free ends of the

levers

53 and 55 apart. This movement apart of the levers is resisted by the fusible or flammable element 57 which is preferably a portion of an old film, the feed sprocket receiving apertures 58 of which provide means for attachment to the pins 56. The fusible or flammable element 57, as bestshown in Figure 1, is disposed adjacent the loop 19 of the film so that assuming a fire Occurs within the feeding mechanism housing, the flames at the loop 19 ignite the element 57 which is immediately consumed permitting the cam shaft 46 to rotate under the stress applied thereto through the cam 43 so that the spring 38 moves blade 27 rapidly over the film passage shearing the film at the edge 36 and forming a barrier between the magazine and the feeding mechanism sprocket. The blade 27 may be readily reset by means of a button 59 carried thereby and extending through an elongated slot 60 in the plate 33.

The spreading of the flame into the magazine along the side of the door 12 is prevented by a door carried channel 61 which fits over the over-hanging side 62' of the member 23 in the manner best shown in Figure 4, the entering edges of the channel 63 being flared, as at 63, to facilitate the passage of the channel over the edge 62 so that the fit between the channel and the member 62 may be comparatively snug.

In Figures 5 and 6, a slightly modified form of my invention is illustrated in which a second movable blade 64 is provided, the movement of the two blades being coordinated by a rack and pinion arrangement 65 and both blades being moved to closed position by springs 66, the release of the locking cam 46 permitting the spring 66 to close the blades onto each otheras will be readily apparent. As the operation of this modification is identical with that previously described, further detail description is deemed unnecessary.

From the foregoing description taken in connection with the accompanying drawings, it will be readily apparent to those skilled in the art to which an invention of the character described appertains that I provide an improved and novel arrangement which. may be readily applied to projectors of all types and makes now in use, or to projectors at the time of manufacture, and one which will very efliciently and positively prevent. spreading of fire into the magazines and consequently will confine the fire to the short length of film within the feeding mechanism housing so that fire damage is reduced to a minimum and further that, by reason of the fire release being located juxtapose the film and spaced from its passage into or out of the magazines, the fire doors are closed and the film severed from the magazines before the fire can enter.

WV hat I claim as my invention is:

1. An attachment for moving picture projectors and operable to close the opening therein through which the film passes in the event of fire, comprising a base member having a film opening extendin medially therethrough, a gate member slida ly mounted to close over the film opening, means normally urging the gate member to its position over the film opening, a catch member readily releasably securing the gate member in its position free of the film opening, means mounting the base member in position, an operating shaft connected with the catch member, and catch retaining means connected with said shaft and including a combustible element destructib-le by fire to release the catch member and permit the rapid movement of the gate member over the film opening.

2. An attachment for moving picture projectors and operable to close the opening therein through which the film passes in the event of fire, comprising a mounting memher having a film receiving opening extending medially therethrough, a gate member slidably carried by the mounting member to close over the film opening, means normally urging the gate member to its position over the film opening, a catch member readily relezisair-ly securing the gate member in its position free of the film opening, means securing the. mounting member in position, an in operating shaft connected with the catch member, and catch retaining means connected with said shaft and including a fusible member whereby the occurrence of fire adjacent said fusible means consumes the same to release the catch member and permit the rapid movement of the gate memher over the film opening, and said gate member having a cutting edge for severing the film at said opening.

# 3. The combination with a moving picture projector magazinehaving an opening through which the film extends and a door, of a base member carried by the magazine and having a film receiving opening with a slot extendin to one side to facilitate the insertion of a filmtherein, a member carried by the magazine door and engageable with the base member to close the slot, a cutting blade slidably mounted to close over the film opening, means normally urging the blade to its position closing the opening, means releasably securing the blade in its position free of the opening, and means operable upon occurrence of fire to permit the movement of the blade to its closed position to completely close the opening to the interior of the magazine.

4. The combination with a film magazine having an opening through which the film passes, of a base member having a film re,

ceiving opening, a cutting blade slidably mounted in the base member to close over the [ilm receiving opening, means normally urging the blade to its closed position, a catch member readily releasably securing the blade in its open position, an operating shaft extended from the catch member, a tubular member carried by the base member in which the operating shaft is freely journuled, an arm fixed to the tubular member,

a second arm fixed to the shaft, and a fusible elementconnect-ing the ends of the arms to maintain the catch member in its operative position holding the blade in its open position, the tubular member forming means for connecting the base member with the n l a guzi ne.

In testimony whereof I afiix my signature.

FRANKLIN SPAULDING.