US1509741A

US1509741A - Apparatus for manipulating cinematograph films

Info

Publication number: US1509741A
Application number: US545581A
Authority: US
Inventors: Way Edward John
Original assignee: BIOSCOPE IMPROVEMENTS Ltd
Current assignee: BIOSCOPE IMPROVEMENTS Ltd
Priority date: 1922-03-21
Filing date: 1922-03-21
Publication date: 1924-09-23
Anticipated expiration: 1941-09-23

Description

Sept. 23 1924.

E. J. WAY

APPARATUS FOR MANIPULAT ING 4 CINEMATQGRAPH FILMS 2 sheets-sheet 1 Filed March 21, 1922 Sept. 23, 1924. v 1,509,741

E. J. WAY

APPARATUS FOR MANIPULATING dINEMATOGRAPH FILMS Filudlarch 21. 1922 2 Sheets-Shut 2 EM. v a

Patented Sept. 23, 1924.

EDWARD JOHN WAY, OF JOHANNESBURG, TRANSVAAL, SOUTH AFRICA, ASSIGNOR TO nro'sco rn IMPROVEMENTS LIMITED,

OF JOHANNESBURG, TRANSVAAL PROV INCE, SOUTH AFRICA, A COMPANY OF THE TRANSVAAL PROVINCE.

APPARATUS FOR MANIPULATING CINEMATOGRAPH FILMS.

Application filed March 21, 1922. Serial No. 545,581.

To all whom it may concern:

Be it known that EDWARD JOHN WAY, a British subject,.residing at Cullinan Buildings, Simmonds Street, Johannesburg,

Transvaal, Province of the Union of South Africa, has invented certainnew and useful Improvements in Apparatus for Manipulating Oinematograph Films, of which the following is a specification.

The present invention has reference to apparatus employed in the cinematograph industry for taking a film from a coil and forming it into another coil, and intermediately subjecting it to an operation such as photographing, printing or projecting a picture from it. One object of the invention is to reduce the stress and damage to the film whilst it is being so treated and to simplify the apparatus by which the film is passed through the intermediate machine.

A further object is to provide a projector which has fewer expensive parts and is consequently cheaper to construct than the projectors now in general use.

In such apparatus it is usual to withdraw the film from the unused coil carrier orspool by means of a sprocket which engages on the film perforations and which is positively rotated. A certain amount of braking force isusually applied to the unused coil spool to prevent its rotating too freely and this force together with that due to the inertia and frictional resistance of the spool and coil have to be transmitted through the sprocket and film. The used coil carrier is generally driven through a friction clutch which is caused to slip by the restraint exercised on the film by another positively driven sprocket. The driving gear for this spool has to be such that it tends to rotate the spool at the relatively high angular speed necessary for the smallest diameter of coil and the slip, and the tension on the film accordingly increase progressively as the coil increases in diameter. These methods of unwinding and rewind ing cause wear and damage to the film at the perforations and striation of both sides of the film due to the creep of thecoils as they are unwound and wound again. The invention aims to eliminate these troubles. The invention consists inan unused coil carrier rotating at a progressivel varying angular speed such as to deliver film at the with the inventionlinear speed at which it is passed through the machine, and a used coil carrier rotated with the unused coil carrier so as to receive the film at the same rate at which it is delivered from the unused coil carrier; the usual sprocket for withdrawing film from the unused coil carrier being done away with, and preferably also the sprocket which regulates the delivery of film to the used coil carrier.

When the operation upon the film is to be repeated a number of times, as in projection, it is desirable that the size of the coil should not be altered by the unwinding and rewinding; whilst owing to there being a certain length of film between the coils, the used coil is necessarily at any moment somewhat smaller than the unused coil. The invention accordingly consists in an arrangement as described, in which the used coil carrier is driven at a slightly higher angular speed than the unused coil carrier.

Since moreover some tension in the film is necessary to produce a used coil which will stand handling, the invention further consists in an arrangement as last described in which the used coil carrier is driven from the unused coil carrier by a friction gear whichtends to drive the used coil carrier,

at an excess speed which provides for the required. diifl erent angular speeds of the carriers and the remainder of which causes slip in the driving connection resulting insuch tension in the film as is necessary to provide a coherent used coil. This slip ,however remains uniform throughout. the

operation and therefore can be accurately maintained within harmless limits.

The invention further consists in such apparatus having an automatic device for regulating the tension of the film winding onto the used coil and for maintaining a loose loop next to the gate, said device not comprising a sprocket.

The invention also consists in the apparatus hereafter described.

In the accompanying drawing there is shown a projector fitted with a film delivering and winding apparatus in accordance Fig. I is a side elevation.

Fig. II is a front elevation seen from the arrow A in Fi I.

Fig. III is a detached detail view.

engagement.

The projector is indicated by 1 and is fitted with any usual or appropriate gate device 2 through which the film is fed in order tb project the picture on the screen.

The film is positively delivered from the unused coil 3 at the same linear speed as that at which it is moved by the gate feed mechanism 2. e A suitable. arrangement for this purpose is described in my Patent No.

1,429,469, of September 19, 1922, and consists of a carrier 4 which holds the unused film and is rotatably mounted upon a frame 5. The under-surface 6 of the carrier is machined to form a friction disc, with which the friction wheel 7 is in driving The shaft 8 on which said wheel 7 is rigidly mounted is driven positively with the gate mechanism 2 through bevel gearing 9. Said shaft 8 can also slide endwise in its bearing 10. Collars =11 fixed on the shaft 8 engage a fork 12 depending from a carriage 13 which is free to travel on a guide 14. From said carriage extends an arm 15 on the end of which is a roller 16 which touches the interior periphery of the unused coil 3. Said roller 16 thus determines the radial position of the friction wheel 7 and as the internal diameter of the film coil increases, the roller 16, carriage 13, shaft 8 and friction wheel 7 move radially outwards, so maintaining the proper speed of delivery of the film.

By means of a film delivering device such as that described, the film is transferred from the unused coil to the gate 2 directly and without the intervention of the usual top sprocket or any device which stresses the film.

The used film is wound as a coil 17 on the spool or carrier 18. For rotating the latter there is mounted on the frame. 5, beneath the carrier 4:, a second friction wheel 19 which touches and is driven by the friction disc 6. Said wheel 19 does not change its radial position during operation; but it is accurately adjustable radially in order to regulate the relative velocities of the two carriers 4 and 18. For this purpose its spindle 20 is provided with thrust collars 21, Fig. III, contacting with a collar 22 on an adjusting screw 23. Upon said screw bein rotated it moves axially and carries the friction wheel 19 with it. This adjustment is preferably made with the machine running.

The spindle 20 of the friction wheel 19 I and the spindle 2a of the spool 18 are coupled by any suitable driving connection such aslthe chain and sprocket gear 25.

The driving connection consisting of the friction wheel 19 and the chain drive 25 is so arranged that the spool 18 tends to rotate with a slight excess of angular speed over that of the carrier 1. A part of this excess is required to rotate the spool 18 somewhat to the coil.

of the radial position of the friction wheel 19 the tension is regulated to that necessary to make the coil 17 wind up sufiiciently tightly to be handled, and this is considerably less than would cause substan tial creeping of the film and striation of its surface. It is also so low that it does not vary in amount between the beginnin and ending of the wind. This tension 0 the film has to be resisted by some device I interposed between the spool 18 and the gate 2. A positively driven sprocket may be used for this purpose, without detriment to the film owing to the tension being of small and constant amount. It is preferred however to employ the tension device shown, as this does not require a driving connection to the gate mechanism and is inexpensive. It comprises a roller 27 revolving freely on a fixed pin 28. The edges of the film are, lightly pinched between said roller and a weighted roller 29 resting on it. Said roller 29 is mounted on a lever 30 pivoted at 31; the other end of which is connected to an adjustable spring 32 by which the normal pressure of the roller 29 on the roller 27 is regulated. A second lever 33 pivoted at 34: and balanced by a weight 35, makes contact with the lever 30 at 36. An arm 37 rigid with the lever 33 carries a plain roller 38 partly encircled by a loop of film 39. Said roller 38 may be mounted in. springs 40 to avoid the possibility of shock to the film. The operation of the device is that if the film winds too fast on the coil 17, the loop 39 is pulled up into co'htact with the roller 38, which tilts the lever 33 clockwise, and through the lever 30 presses the roller 39 more tightly on the film, thereby increasing the tension in the film and causing slip between the friction wheel 19 and the friction disc 6. The rate of feeding film to the coil 17 is slowed down, causing the loop 39 to increase in size and recede from the roller 38; where upon the additional pressure. between the

rollers

27 and 29 ceases and the normal feeding of the film is resumed.

With the construction above described a considerable number of gears usually required in a projector are eliminated. In the arrangement shown the driving motor is belted to a pulley 4.1 which is on the same spindle as the intermittent feed 12 and the fly wheel 13.v An idler 1 1 transmits motion to the gear wheel 45 on the shaft 46 which drives the bevel gears 9 of the film deliver- 4 the unused coil carrier.

ing device and said gear wheel rotates the shutter device 47. That isto say, there are eight out gears with their bearings and lubricating systems as against fifteen cut gears and the top and bottom sprockets usually present in standard machines.

I claim:

1. In film manipulating apparatus, the combination of means for utilizing a film, a rotatable carrier for unused film coil, means for rotating the latter to deliver film without tension, and a carrier'for used film coil driven fromthe unused coil carrier to rotate at substantially the same speed as the unused coil carrier.

2. In film manipulating apparatus, the combination with means to utilize a film and including a positive film feed, of a carrier for unused film coil driven with said film feed and delivering film without tension in consonance with its movement by said feed, and a carrier for used film coil drivn from 3. In film manipulating apparatus, the combination of an unused coil carrier, means to rotate the same with progressively varying speed inversely proportional to the varying diameter of a coil thereon, and a carrier.

for used coil driven by the unused coil carrier. Y

4. In film manipulating apparatus, the combination of an unused coil carrier from which 'film is delivered without tension, a carrier for used film coil, and frictional means by which the used coil carrier is driven by the unused coil carrier.

5. In film manipulating apparatus, the combination of an unused coil carrier, means to rotate the same with progressively varying angular speed, a used coil carrier, and a frictional driving connection from the unused coil carrier to the used coil carrier tendto differentiate slightly the relative ang 'ifiar speeds of the two carriers.

6. In film manipulating apparatus, the combination with a rotatable film coil carrier, a friction disc rotating therewith, a driving friction wheel e a the friction disc and traversable rai gi y thereof, another rotatable coil carrier, anda frictional driving connection whereby the first mentioned carrier drives the second mentioned carrier.

7. In film manipulatinv apparatus, the combination with a rotata le film coil carrier, a friction disc rotating therewith, a driving friction wheel eng l L the friction disc and traversable 1 y thereof,

another rotatable coil carrier, and a fric-' tional driving connection whereby the first mentioned carrier drives the second men tioned carrier while tending slightly to differentiate their angular speeds.

8. In film manipulating apparatus, the combination with a rotatable carrier for unused film coil, a friction disc rotating therewith, a friction wheel driving said friction disc and traversable radially thereof, means controlling the radial position of the friction wheel, a second friction wheel engaging the friction disc, a rotatable carrier for used film coil and a driving connection between the second friction wheel and the used coil carrier.

9. In film manipulating apparatus the combination with a rotatable carrier for unused film coil, a friction disc rotating there with, a friction wheel driving said friction disc and traversable radially thereof, means touching the interior of the unused film coil and controlling the radial position of the friction wheel, a carrier for unused film coil, and means whereby the latter is driven from the unused coil carrier.

10. In film manipulating apparatus, the combination of a rotatable carrier for unused film coil, a rotatable carrier for used film coil, frictional means whereby the unused coil carrier drives the used coil carrier, said means tending to drive the used coil carrier faster than the unused coil carrier, and film restraining means in advance of the used coil carrier.

11. In film manipulating apparatus, the combination of a rotatable carrier for unused film coil, a rotatable carrier for used film coil, frictional driving connection between the two carriers tending to drive the used coil carrier faster than the unused coil carrier and frictional film restralning means.

in advance of the used coil carrier.

12. In film manipulating apparatus, the combination of a rotatable carrier for unused film coil, a rotatable carrier for used film coil, a frictional driving connection be tween the two carriers, tending to drive the used coil carrier faster than the unused coil carrier, frictional film restraining means in advance of the used coil carrier, and cans governed by the tension of the film I} advance of said restraining means for co trolling the frictional resistance exerted on the film by said restraining means.

In testimony whereof I aflix my signature. J

EDWARD JOHN WAY.