US3323746A

US3323746A - Automatic end fastener for film spool

Info

Publication number: US3323746A
Application number: US496783A
Authority: US
Inventors: Mouissie Bob
Original assignee: Paillard SA
Current assignee: Paillard SA
Priority date: 1965-02-18
Filing date: 1965-10-18
Publication date: 1967-06-06
Anticipated expiration: 1984-06-06
Also published as: DE1499824A1; GB1079482A; AT258120B; CH410627A

Description

June 6, 1967 B. MOUISSIE 3,

AUTOMATIC END FASTI QNER FOR FILM SPOOL I Filed 06th 18, 1965 FIG. 4

FIG. 6'

-FIG. 5'

INVENTOR 30B Woo/ 5 BY w M ATTORNEY United States Patent 3,323,746 AUTOMATIC END FASTENER FOR'FILM SPOOL Bob Monissie, Yverdon, Switzerland,assignor to Paillard A., Sainte-Croix, Vaud, Switzerland, a corporation of Switzerland Filed Oct. 18,1965, Ser. No. 496,783 Claims priority, application SwitzerlantLFeb. 18, 1965,

2,247/ 65 j, 6 Claims."(Cl. 24274.2)

Film spools are already known, chiefly spools carry ing a kinematographic film, which include a hub, two flanges and parts projecting elastically with reference to the inner surfaces of said flanges and extending between the hub and the periphery of the spool. Said elastic parts are adapted to clamp the free end of the film, so as to allow winding the latter around the spool. In'order to ensure such a clamping, the film has to be positioned manually over the spool.

The object of the present invention is to allow an automatic securing of the film round the spool without any manual operation, which is of course 'of considerable advantage, chiefly in the case of kinematographic projectors provided with an automatic arrangement for the positioning of the film. As a matter of fact, in such projectors, channels guide the film so as to make it pass from its feeding means into registry with the projection gate, but the operator is generally constrained to anchor by hand the film on the take up spool.

My improved spool distinguishes with reference to the above-mentioned known spools through the fact that the elastic parts carried by one flange are-angularly shifted with reference to the corresponding parts on the other flange.

The accompanying drawing illustrates diagrammatically and by way of example a preferred embodiment of my invention.

In said drawings:

FIG. 1 is a side view of one-half the spool, partly in section through the hub thereof,

FIG. 2 illustrates thecomplete spool as it would appear viewed in the direction of the arrow A of said FIG. 1,

FIG. 3 is a sectional view of a part of the spool,

FIG. 4 is a parti-al'side view on a larger scale of a detail of the spool,

FIGS. 5 to 9 illustrate the operation of said spool.

Turning to FIGS. 1 and 2, the spool illustrated includes two flanges 1 and 2 located to either side of a hub 3. Each flange is provided with an axial opening 4 along the periphery of which are cut radial notches 5 through which the spool can be fitted over a driving shaft provided with radial projections corresponding thereto, wherethrough the spool may be driven into rotation by said shaft.

Each flange shows on its inner surface six grooves 6 terminating near the periphery of the flange with :a port 7 communicating with a groove 8 formed on the outer surface of said flange. The hub 3 is provided with short longitudinal slots 9 which allow the passage through them of elongated members or rods 10 forming parts projecting elastically over the inner surface of the flange. Said rods 10 terminate each with a bent end 11, which end engages the corresponding port 7, whereby a pivotal connection is obtained for said rod adjacent the periphery of the flange. The inner end of the rod 10 is elastically urged towards the medial plane of the spool, by a spring constituted by a resilient tongue 12 cut out of a sheet steel disc 13 extending over the central section of the flange considered within the area of the hub 3. Thus, the rods 10 are shifted gradually away from the flange as they are considered nearer the center of the spool. As illustrated in FIG. 1,

the rods 10 carried by one of the flanges 1 are angularly shifted with reference to the rods 10' of the other flange 2 which are diagrammatically shown in FIG. 1 by the superimposed broken lines 10. Furthermore, the inner ends of said rods 10 and 10' extend in a direction passing outside the spool axis and not through the center axis of said opening 4. Through such an arrangement, an excellent clamping of the film is obtained when the latter is fitted between the two flanges 1 and 2, said clamping action increasing for the portion of the film nearest the hub.

By reason of the angular shifting or staggered disposition between each pair of opposed rods 10 and 10' on the two flanges and also by reason of the oblique arrangement of each rod with reference to a radial direction, the film is clamped throughout between a rod 10 or 10' and a portion of flat surface of the flange 2 or 1, respectively, op-

posed that carrying the rod considered. Consequently, if

the film is subjected to a tensioning which has a tendency to modify its slope at the point at which it is clamped by one of said parts, a non negligible friction appears along the film edge which is urged along the corresponding flange so as to oppose its movement.

FIGS. 5 to 9 illustrate the movements of the film while it is being anchored automatically on the spool. It should first be remembered that on a projector, the take-up spool is driven through the agency of a friction coupling and that, in the absence of any slip in said coupling, the tangential speed of the hub of the spool is higher than the speed at which the film is fed to the spool.

FIG. 5 shows the introduction of the film F at a speed V between the flanges of a spool which is driven into ro tation and of which the tangential speed V is larger than V The film F passes out of a guiding channel which is not illustrated and its rigidity is suflicient for it to engage the gap between the flanges of the spool without any further guiding means being required.

By reason of the rotation of the spool, the film F engages first a rod such as 10 which provides a slight elastic clamping of the end of the film. As the spool rotates and the film continues its travel, it engages in succession each opposed pair of rods 10 and 10' located in staggered alternation on the inner surface of each of the flanges 1 and 2.

FIGS. 6 to 8 illustrate the gradual Winding of the film round the hub of the spool. As soon as the film has reached the position illustrated in FIG. 8, the traction to which it is subjected as a consequence of the torque acting on the spool and of the clamping of the film by the

rods

10 and 10 produces a centripetal force which urges the film towards the hub 3. Since the film slides with reference to the pressure-exerting rods by reason of the difference between the speed of the spool and the speed of progression of the film, the end of the film which was comparatively far from the hub 3 is urged gradually towards the latter. As a matter of fact and as a consequence of the film bearing against one of the flanges of the spool in registry with each

rod

10 or 10 engaging one edge of the film, there arises, as already mentioned hereinabove, a non-negligible resistance opposing a change in the angular setting of the film at the point at which it is clamped. Thus, the point a in FIG. 8 shows the location at which a pressure is exerted on the film by a rod 10. Said rod moves clockwise quicker than the film and the point a shows in FIG. 9 that point very near the extreme end portion of the film where the greatest pressure is exerted upon the film. It is thus apparent that this extreme portion of the film is speedily led towards the hub so as to be finally engaged in contacting relationship therewith. As soon as the film has executed more than one convolution round the hub, a self clamping of the film is obtained and the film is thus held fast energetically against the spool hub.

Obviously, numerous modifications may be brought to the spool described, the chief feature consisting in that the elastic parts of one flange are angularly shifted with refer- V ence to the parts of the other flange. In the case of flanges formed by steel sheets, the springs acting on the ends of the rods may be constituted readily by tongues cut in the metal sheet-s forming the flanges. In a simpler structure, the elastic rods may also be constituted by tongues cut in the steel sheets forming the flanges.

In the embodiment described, the two flanges were similar which is of a considerable advantage from the standpoint of manufacture, but obviously such a symmetry is not essential and also the number of rods provided on each flange may be modified, although it is preferable to use at least three rods on each flange.

What I claim is:

1. A spool, chiefly for kinematographic films, comprising a hub, two parallel flanges carried by said hub, two series of elongated members projecting inwardly from the inner surface of the corresponding flange and extending between the hub and the outer periphery of said flanges, means within said hub engaging the free inner ends of said members on both of said flanges to elastically urge the inner ends of said members towards the medial plane of said spool, said means yieldable against an outside force to permit outward displacement of the inner I ends of said members, and the inner ends of one series of members on one of said flanges being disposed in staggered angular relationship to the inner ends of the other series of members on the other one of saidrflanges.

2. A spool, chiefly for kinematographic films, comprising a hub, two parallel flanges carried by said hub, two series of elongated members on the inner surface of said flanges, each member forming an angle with a radius of the flange carrying it, which is different from the angle formed by the corresponding member carried by the flange opposed to the last mentioned flange with said radius, said members projecting over the inner surfaces of the corresponding flanges and extending between the hub and the outer periphery of said flanges, means between said flanges spring urging the inner ends of said members towards the medial plane of said spool, and said members caried by one of said flanges being disposed in staggered relationship 7 with those members carried by the other of said flanges;

3. A spool, chiefly for kinematographic films, comprising a hub, two parallel flanges carried by said hub and two series of elongated members pivotally connected to each of the corresponding flanges at points distributed adjacent the periphery of the latter, said elongated members extending over the surfaces of said corresponding flanges with a gradually increasing spacing with reference to the latter towards the hub, and spring means located adjacent the hub and urging the different members elastically away from the portion of the corresponding flange adjacent the hub, and the members carried by one flange being out of transverse registry with those carried by the other flange.

4. A spool according to claim 1, wherein said two parallel flanges are of similar construction and are attached to said hub in a radially displaced relationship to provide said staggered arrangement of the inner ends of said opposed members.

5. A spool, chiefly for kinematographic films, comprising a hub, a'pair of flanges carried by said hub, two parallel disc elements carried by said hub, a plurality of incurved tongues cut out of the peripheral portions of said discs, and two series of elongated members pivotally connected to each of the corresponding flanges at points distributed adjacent the periphery of the latter, said members extending over the surfaces of said corresponding flanges with a gradually increasing spacing with reference to the latter towards said hub, said members being urged elastically away from the portion of the corresponding flange adjacent the hub by said tongues cut out of said disc elements. I t

6. A spool, chiefly for kinematographic films, comprising a hub, two parallel flanges carried by said hub, two series of film-clamping rods respectively carried by said flanges, each film-clamping rod forming an angle with a radius of the flange carrying it, which is different from the angle formed by the corresponding film-clamping rod carried by the flange opposed to the last-mentioned flange with said radius, said film-clamping rods projecting elastically over the inner surfaces of the corresponding flanges and extending between the hub and the outer periphery of said flanges, the film-clamping rods carried by one flange being out of transverse registry with those opposed rods carried by the other flange.

References Cited UNITED STATES PATENTS 1,861,882 6/1932 ,Ross 24274.2 1,861,891 6/1932 Wittel 24274.2 2,004,608 6/;1935 Howell 24274.2

FRANK J. COHEN, Primary Examiner.

N. L. MINTZ, Assistant Examiner.