US2094922A - Film winding apparatus - Google Patents

Description

Oct. 5, 1937. w. E. JOHN f 2,094,922 FILM WINDING-APPARAT S Filed Aug. 10,1935

INYENTOFV. ,7 Wesun ERNEST @Hht FITTOR NEIS I Patented a. 5, 1937 UNITED STATES 2,094,922 FILM WINDING APPARATUS r I Wesley Ernest John, Johannesburg, Transvaal, Union of South Africa I T Application August 10,

1935, Serial No. 35,591

In Great Britain October 1, 1934 Claims.

The present invention relates to film winding apparatus for kinematograph-machines, of the kindv in which the film is fed from the inner periphery. of the delivery film coil, to the gate 5 feed mechanism and is wound onto the outer periphery of the receiving filmcoil; so that the wound receiving coil is ready for re-use without re-winding.

The particular problem presented in apparatus of this kind is to rotate the delivery coil car-" rier with a high degree of precision at the continually varying angular speed necessary to ensure that film is pushed out from theinner peripheryof the coil on said carrier at.a linear speed which is constant relatively to the linear speed due to the gate feed mechanism.

' According to the present invention the carrier for the receiving coil =is driven with the gate feed mechanism in the usual manner through a slipping clutchwhereby the linear speed of the film winding on to it is equal to the linear speed of the film through the. gate and its angular speed is constantly varied according to the increasing diameter of the receiving coil. The delivery coil 5 carrier is driven from the receiving coil carrier; by which means its angular speed may be made equal to" that of the receiving coil carrier and the rate of film delivery from its coil approximated to the rate'of film winding on the receiving coil. It is necessary'however that the angu-.

lar speed of the two carriers'shoulddiffer by a slight-and non-constant amount, due, among other things to there being always a length of film unwound from the delivery coil and not ,35 wound onto the receiving coil. Thisxdiflerence of angular speed isprovided for by including in the driving connection betweenthe two carriers,

a variable speed mechanism. .There is further provided a movable roller structure adapted to engage both faces of the film and a fixed roller co-operating with said roller structure to form the film issuing from the inner periphery of the delivery film coil into a substantially V-shaped loop with the roller structure at its apex. Said roller structure is arranged for movement to follow variation in the length of the loop, and by such movement so to vary the velocity ratio of the variable speed mechanism as to oppose change in the length of the loop.

A preferred form of the invention is shown in the accompanying drawing in which:

Figure I is an elevation of part of a kinematograph projector.

Figure II is an elevation at right angles to Figure I.

Figure III is a part plan; Figures II and III being on, a larger scale than Figure I. g

2 indicates a film gate with feed mechanis'm 3 driven by a shaft 4. 5 is the receiving film coil wound onto its carrier 6. The latter is'a spool one side 1 of which is displaceable to permit th'e wound coil 5 to be removed from it. Said spool 6 is removably secured on a shaft 8 drivenfrom the shaft 4 through mechanism 9 and a slipping clutch 10. i

l I is the delivery film coil carried in a horizontal carrier 12 which allows film to be passed out from the inner periphery l3 of the coil 1 l. Said carrier is secured on a vertical shaft l4 mounted in the frame member l5.

I6 is a grooved pulley fast on the shaft! and connected by a belt ll to a conepulley l8 fast on the shaft I4. The diameter of pulley l8 approximates to that of pulley I6. The belt' H can be shifted up and down the cone pulley I8, to vary the angular speed of the attached carrier 12, by means of the movable belt fork I9, provided on one arm 20 of abell crank 20, 2 I. Thelatter is pivoted tothe frame at 22 to oscillate in a verticalplane.

The other arm 2| of the lever extends approximately vertically so that its upper end oscillates approximately horizontally. At its upper end it carries the freely rotatable roller 23 and the two freely rotatable rollers 24, from the roller 23 to permit film to be inserted between them. V f

25 is a sprocket driven positively with the gate feed mechanism 3 by. a connection 26. It is mounted on the frame in such a position that film issuing from the periphery l3 of the coil II and fed first around the roller 23 and then around roller 25, forms an approximately V-shaped loop consisting of the. two legs 21 and having the roller 23 at its apex. The path of displacement of the roller 23 permitted by the bell incides with the direction in which the apex' of the loop tends to move when the loop is lengthened or shortened. By such means as a shiftable weight 28, the bell crank is nicely balanced about its pivot 22 and can thus be moved by the small .forces exerted through the legs 21 of the film loop when the latterlengthens or contracts owing to the angular speed of its carrier being too high or too low relatively to the linear speed of the film through the gate. Shortening of the loop causes it to press on the roller 23, whilst lengthening of the loop causes it to press on the rollers 24. By such movement of the bell crank the belt I1 is shifted up or down the cone pulley to 24 spaced sufficiently latter and its 40' crank 20,,21' cocorrect the angular speed. It is preferable so to bias the bell crank 20, II by means of the weight '28 thatthe tendency is always to overfeed slightly,-such tendency being corrected by sure of the'film on the rollers 24.

the pres Such means as an extension of shaft i4, having a freely rotatable sleeve 29 forming a cen- 'tral pillar, is provided to prevent coils of film from being pulled out of the carrier if it should happenethat, foranyreason, the film, is :drawn too rapidly. from said carrier 12.

I claim: '1. Film winding apparatus for kinematograph machines comprising a rotatable delivery film coil carrier, a gate feed mechanism, a rotatable receiving film coil carrier, a frame on which the said parts are mounted, means for withdrawing .film from the inner periphery of a c 'oil'v of film in the delivery carrier through the gate feed mechanism and feeding it to the outer periphery of a coil of film in the receiving carrier, a driving device for driving the gate'feed mechanism, means including a slipping clutch fordrivto cause said lever to rotate in response to variations in the length of said loop; the other end of said lever co-operating with said variable speed mechanism for, controlling the speed of'rotation of the delivery carrier in accordance with the length of said loop.

2; Filmwinding apparatus for kinematograph' machines comprising a rotatable delivery film coil carrier, agate feed mechanism, a rotatable rev ceiving film coil, carrier, a frame on which the said parts are mounted,- means iforwithclrawing film from the inner periphery of a coil of film in the delivery carrierthrough the gate feed mechanism a'nd feeding it to the outer peripheryof a "coil of filmin the receiving carrier, a drivingdevice fordrivin'g the gate feed mechanism, means including a; slipping clutch for driving the receivl lngj carrier from said driving device, a driving I 1 connection from the "receiving carrier to the de-, 50.

liveryjcarrier including a'variable speed mechanism, a bell crank lever pivotally mounted on the l i frame with one arm upright, rollers at the end of said arm engaging both faces of a loop of film on'fits way'to'the gate mechanism to cause said lever to rock inresponse tothe variations in the length ofsaid loop; the other end of said lever lcrank lever for balancing said lever about its 'co-operating with said variablespeed mechanism forcontrollin'gthe speed of rotation ofthe ,delivery'carrier: in accordance with the length ofsaid loop',and a shiftable weight on 'said bell vpivot when the film is in position, I I a winding'apparatus for kinematograph jmach inescomprising a rotatable'delivery film coil carrier, a gate feed' mechanism, a rotatable receiving film coil carrier, a frame on which said delivery carrier through the gate feed mechanism parts are mounted, means for withdrawing film fromthe innenperiphery of a coilof film in the and feeding, it to the outer'periphery er a coil of film in the receiving carrier, a driving device for driving the gate feed mechanism, means1in-- cluding a slipping clutch for driving the receiving carrier from said driving device, a belt pulley rigid with the receiving carrier, a cone pulley rigid with the delivery carrier, 2, driving belt connecting said 'pulleys, a bell crank lever pivotally mountedon the frame with one arm up{ right, rollers at {the end of said arm engaging both faces of a loop of film on its" Way to the gate mechanism to cause said lever to rotate in response, to variations in the length of said loop, the other end of said lever co-operating with said belt for shifting it along the cone pulley to vary the speed of the delivery carrier in accordance with the length of film between the de livery carrier andthe gate mechanism.

4. Film winding apparatus for kinematograph machines comprising a rotatable delivery film coil carrier, a gate feed mechanism, a rotatable receiv ing film coil oarrierya frame onv which the said parts are mounted, -means for withdrawing film from the inner periphery of a coil of film inv the delivery carrier through the gate feed mechanism and feeding it to the outer periphery of a' coil of film in the receiving carrier, a drivingjdevice for driving the gate feed mechanism, means including a slipping clutch for driving the receiving carrier from said driving device, a driving connection from the receiving carrier. to the delivery carrier including avariable speed mechanism, amovable'roller structure, adaptedto engage both faces of the film, a fixed roller -cooperating with saidroller structure toiform the film issuing from the inner periphery of the del l livery film coil into a substantially V-shaped' loop with the movable roller structure at its apex, said follow variation in the length ofthe loop, and by 'such movement so varying the velocity ratio of the variable speed mechanism as to oppose change ln'thelengtlrof the loop.

.roller structure being arranged for movement'to 5. Film winding apparatus forkinematograph 'machinesmomprising a rotatable deliveryfilm coil carrier, a gate feed mechanism, arotatable,

1 receiving film coil carrier, .a frame on which the said parts are mounted, means for-withdrawing film from the inner periphery of a'coil of film in the delivery carrier through'the gatefeed mechanism and feeding it to the outer periphery of a coil of filn'rzin-the-receiving carrier, 9, driving device for driving the gate feed mechanism, 7 means including a slipping clutch for driving the receiving carrier from said driving device, abelt pulley rigid with the receivingv carrier," a cone pulley rigid with the delivery carrien-za driving belt connecting said pulleys, a movable roller structure adapted to engage both faces of the film,- q a fixedroller co-operating with said rollerstructure to form the film issuing from the inner periphery of the delivery film coil into asubstantially V-shaped loop with-the, movable roller I structure at its apex, and means controlled by said roller structure forishifting the belt along the'cone pulley so "as to vary the velocityof the,

delivery film coil carrier in such a .way as to oppose change in the length of the loop.

' 1 a WESLEYERNESTJOHN.

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