US2102843A

US2102843A - Ribbon feeding mechanism

Info

Publication number: US2102843A
Application number: US77524A
Authority: US
Inventors: Hugh H Gwynne
Original assignee: Individual
Current assignee: Individual
Priority date: 1936-05-02
Filing date: 1936-05-02
Publication date: 1937-12-21
Anticipated expiration: 1954-12-21

Description

Patented Dec. 21, 1937 UNITED' STATiEh PATENT OFFICE 1 Claim.

This invention relates to a ribbon feeding mechanism and more particularly pertains to a machine for conveying a ribbon through a series of baths, such as is employed in the treatment of motion picture films.

An object of the invention is to providea mechanism whereby a considerable length of ribbon may be advanced between a feeding reel and a take up reel and passed successively through a series of compartments in such manner as to avoid stretching of the ribbon and yet permit longitudinal expansion and contraction thereof such as may occur in wetting and drying the ribbon during its course of travel from the feeding reel to the take up reel.

Another object is to provide a mechanism of the above character in which the ribbon is caused to traverse a substantially zig-zag path of travel in advancing it in and out of a plurality of compartments by passing the ribbon back and forth around -a series of rollers, and in which means are provided for minimizing longitudinal strains on the ribbon throughout the length thereof extending between the feeding and take up reels.

' Another object is to provide a means whereby on winding the ribbon being worked on a take up reel compensation will be aiforded for the increasing diameter of the ribbon roll without variation in the speed of travel of the ribbon or of longitudinal strains thereon.

Another object is to provide a construction whereby a portion of the length of the ribbon being advanced between the feeding and take up reels may be caused to be submerged in a bath for various lengths of time while advancing the ribbon at one speed by causing a variation in the length of ribbon being submerged.

Another object is to provide a mounting for the ribbon feeding mechanism whereby the ribbon may be readily introduced into and removed from the series of compartments containing the ribbon treating fluids and whereby the various parts of the machine conveying the ribbon are rendered easily accessible to facilitate effecting repair of the ribbon in event of breakage thereof during its passage through the compartments.

A further object is to provide a ribbon feeding mechanism of the above character which functions in such fashion that in event of breakage (Cl. 27l2.3)

with such other objects and advantages as may subsequently appear, the invention is carried into effect as illustrated by way of example in the accompanying drawings, in which:

Fig. l is a view in vertical section and eleva- 5 tion of the ribbon feeding mechanism with parts removed, showing the invention as applied in the developing of a motion picture film;

Fig. 2 is a view in vertical section and elevatio taken on the line of Fig. 1; 10

Fig. 3 is a view in vertical section and elevation as seen on the line of Fig. 1;

Fig. l is a detail plan view as seen on the line l4 of Fig. 1.

Referring to the drawings more specifically A 15 indicates generally a carriage which may be of any suitable construction to afford a support for a ribbon feeding mechanism as will be presently described. The carriage A extends horizontally over the open upper end of a housing B contain- 00 ing a series of compartments of any suitable number arranged in a row beneath the carriage A and here shown as comprising six compartments C, D, E, F, G, and H, with adjacent compartments separated from each other by partitions 5. The carriage A is designed to be raised and lowered relative to the housing B and when in its lowered position to be supported in a stationary positionpreferably on the housing. As here shown thecarriage is disposed in its lowermost position and seated on brackets 5 arranged at opposite ends of the housing B and projectingKthereabove; the carriage being fitted with downwardly extending guide rods l slidably extending through openings in the brackets b for guiding thecarriage A in its vertical path of travel.

Movement of the carriage A may be eitected in any desired manner, such, for example, as by cables 8 attached to the end portions of the carriage and leading upwardly therefrom to any appropriate means of taking up or letting out the cable, such as a winch or counter-weights, not necessary to be here shown.

Depending from the end portions of the car- Ly riage A exteriorly of the housing B and adjacent the ends of the latter are hangers 9 and ill on which are mounted respectively a ribbon feed reel H, and a ribbon take up reel [2. The reel H carrying a ribbon [3 to be fed to the reel I2 is loosely supported on the hanger 9 to rotate idly while the take up reel I2 is mounted for driven rotation, being here shown as carried on a shaft 14 fitted with a pulley l5 engaged by a belt l6 passing over a pulley ll on a shaft I8,

through which the reel I2 is revolved to take up the ribbon |3.

The shaft I8 is journalled in bearings l9 on the carriage A as particularly shown in Fig. 4; the shaft extending transversely of the carriage and being fitted with a gear wheel 20 engaged by a pinion 2| on the drive shaft 22 of a motor 23 carrried by the carriage A.

Mounted on the shaft I8 is a sprocket 24 with which is engaged a sprocket chain 25 leading longitudinally of the carriage A and passing around and engaging a sprocket 26 on a shaft 21 journalled in bearings on the end portion of the carriage A adjacent the hanger 9. The shaft 21 extends transversely of the carriage A and is fitted atits forward end with a roller J positioned forward of the carriage A in line with the feed reel II and around which roller the ribbon |6 is passed and directed downwardly therefrom as will presently be described.

Arranged at intervals along the length of the carriage A between the shafts 21 and I8 is a series of

shafts

28, 29, 36, 3|, 32, and 33 and which may be of any suitable number according to the number of compartments in the housing B; a shaft of such series being provided to extend transversely of the carriage A on a vertical plane proximate each partition 5 in the housing B and with the end shaft 33 of the series disposed on a vertical plane proximate the plane of the end wall of the housing B adjacent the take up reel l2. The

shafts

28, 29, 30, 3|, 32, and 33 are each fitted with a sprocket 34 engaged by the sprocket chain 25, which sprockets and the

sprockets

24 and 26 are of corresponding diameters and have corresponding numbers of teeth so that on rotation of the sprocket drive shaft I8 the several sprockets and their associated shafts will be rotated at corresponding speeds. Mounted on the forward ends of the shafts Z8,

29, 30, 3|, 32, and 33 are flanged rollers K, L, M,

N, O, and P positioned in alignment with the roller J on the shaft 21 and around which the ribbon I3 is passed.

Projecting downwardly from the carriage A for positioning in the compartment C is a frame embodying a pair of parallel Vertically extending guide rods 35 connected together at their lower ends by a horizontal bar 36, and slidably supported and guided on the rods 35 for vertical,

movement is a carriage Q fitted with sleeves 31 slidably engaging the guide rods 35. A central hub 38 on the carriage Q is formed with an internally threaded bore having screw engagement with a vertically extending threaded shaft 39 leading from a foot bearing 40 on the bar 36; the shaft extending parallel with the guide rods 35 and connecting at its upper end to a shaft 4| leading through a bearing 42 on the carriage A and fitted at its upper end with a hand wheel 43 for effecting manual rotation of the shafts 4| and 39 to effect vertical movement of the carriage Q.

Carried by the guide rods 35 adjacent the upper ends thereof and above the threaded shaft 39, is a cross bar 44 rigidly aflixed tthe guide rods and having a sleeve 45 through which the shaft 4| extends, and mounted on the carriage Q and cross bar 44 is a series of direction rollers R, S, and T around which the ribbon 3 leading from the roller J to the roller K is passed. The set of rollers carried by the carriage Q and bar 44 may be of any suitable number according to the length of ribbon desired tobe extended between the rollers J and K, being here shown as three in number by way of example, with the roller R carried on the carriage Q, the roller S on the bar 44, and the roller T on the carriage Q, with the ribbon leading downwardly from the roller J around the roller R then upwardly over and around the roller S and downwardly around the roller T and upwardly over the roller K.

Depending from the under side of the carriage A is a series of

hangers

46, 41, 48, 49, and 59 arranged for positioning within the compartment D, E, F, G, and H, and mounted respectively on the lower ends of said hangers are flanged idler rollers U, V, W, X, and Y around which the rib-,

bon I3 is passed; the length of ribbon leading from the roller K to the roller L passing around the roller U; the length of ribbon leading from the roller L to the roller M passing around the roller V; the length of ribbon leading from the roller M to the roller N passing around the roller W; the length of ribbon leading from the roller N to the roller 0 passing around the roller X, and the length of ribbon leading from the roller 0 to the roller P passing around the roller Y. The ribbon |3 after passsing over the roller P is directed downwardly and engaged with the take up reel I2.

The

hangers

46, 41, 48, 49, and 50 may be of any desired length according to the depth of their projection into their respective compartments as may be desired. For example the hanger 41 extending into the compartment E is much shorter than that of the other hangers.

While the hangers are each shown as equipped with a single roller the number of rollers carried by each hanger may be increased and a plurality of rollers arranged in a fashion similar to that of the rollers R, S, and T, where it is desired to provide a greater length of ribbon leading through any of the compartments.

In carrying out the invention each of the several rollers over which the ribbon is passed is designed to have sliding contact with the ribbon; the rollers being free of teeth or spurs such as would effect positive engagement with the ribbon, and by which arrangement such pull as is imparted to the ribbon by rotation of the impelling rollers J, K, L, M, N, O, and P will be effected solely by the frictional contact of the rollers with the ribbon. The ribbon is thus free to move lengthwise independent of the rollers either under expansion and contraction or in forming or taking up of slack therein.

An important feature of the invention resides in imposing a load on the ribbon as it passes over roller P which is accomplished by means of a weighted roller Z carried on the arm 5| pivoted at 52 on a standard 53 mounted on the carriage A; the roller Z being positioned to bear on the portion of the ribbon'passing over the roller P so as to effect a frictional contact between the ribbon and roller P in accordance with the load imposed on the ribbon by the weight of the roller Z.

The action of the weighted roller Z is to maintain such frictional contact between the roller P and the ribbon |3 as willovercome and substantially balance the resistance to advance of the ribbon around the several idler rollers R, S, T, U, V, W, X, and Y, so as to minimize slippage between the ribbon and the traction rollers J, K, L; M, N, O and P.

The various compartments of the housing B are designed to contain various fluids according to the particular treatment to which the ribbon is to be subjected. For example, in the treatment of a motion picture film the compartment C may serve as a reservoir for a developing liquid, compartment D a reservoir for rinse water, compartment E a reservoir for a fixing bath, compartments F and G for wash water and alcohol respectively, and compartment H as an air drying chamber in which the ribbon is dried after passing through the several liquids and before being delivered to the take up reel. Drying action of the ribbon in the chamber H may be augmented by passing air through the chamber through the medium of a blower 55 and which air may be heated to any suitable temperature in a usual manner.

Where desired the ribbon may be subjected to a wiping action as it leaves a bath and for which purpose may be passed between a pair of wiping rollers 56 as shown in Fig. 1, in which such rollers are shown as arranged to engage the length of ribbon leading to the roller K as it passes from the compartment C. The rollers 56 engage opposite sides of the ribbon under slight pressure; being here shown as carried on depending arms 51 connected by a spring 58 in such manner as to cause the rollers to press or bear against opposite sides of the ribbon under the urge of the spring.

In the operation of the invention a feed length of ribbon is initially rove around the several rollers in the fashion previously described andas depicted in Fig. 1 which obviously is effected with the carriage A positioned to dispose the hangers exteriorly of the housing. One end of the feed ribbon is attached to the winding reel l2 and the other end is attached to a ribbon l3 on the reel H. The carriage A is then lowered to its seated position on the bracket 6 to dispose the several hangers in the housing.

To obtain a desired length of submersion of the ribbon in the liquid in compartment C the carriage Q is raised or lowered by rotation of the threaded shaft 39 as before described, thus timing the action to which the ribbon is subjected by the liquid in compartment C.

To effect feeding of the ribbon the sprocket chain 25 is set in motion by driving the sprocket 24 in a clock-wise direction as viewed in Fig. 1 by rotating the shaft 18, thus eifecting rotation of the ribbon driving rollers J, K, L, M, N, O, and P. At the same time the take up reel I2 is driven from the shaft l8 by the belt l6.

By reason of the tension imposed on the ribbon by the weighted roller Z initial rotation of the roller P causes the latter to advance the leading 7 end portion of the ribbon rearward of roller P to take up any slack therein between the rollers P and 0 such as to bring the portion of the ribbon passing over the roller 0 into frictional engagement therewith, whereupon the roller 0 will then act to take up any slack in the ribbon between the rollers O and N. In like fashion the rollers M, L, K, and J each successively take up slack in the lengths of ribbon immediately preceding each of said rollers until the ribbon is drawn taut throughout the length thereof extending from the reel l l to roller P whereupon the ribbon will be frictionally engaged under corresponding traction values on the several driving rollers and with slight equal tension imposed on the length of ribbon leading between adjacent driving rollers. e

The length of ribbon leading from the end roller P and advanced by the latter is wound on the take up reel I2 on which a roll of the ribbon is built up gradually increases the diameter and which normally would accelerate the speed of travel of the ribbon. This action of the increased diameter of the roll however is compensated for by arranging the belt 16 so that the latter will slip on its associated pulleys l5 and I! when a load is imposed thereon such as would effect advance of the ribbon at a speed faster than that effected by the driving roller P under traction afforded by the weighted roller Z. In this fashion the take up reel l2 operates only to Wind up the slack in the length of ribbon leading from the end roller P and does not function to pull the ribbon through the machine.

In order to adapt the ribbon feeding and driving mechanism to exert the minimum pull required to effect advance of the ribbon, the load imposed by the roller Z is made to correspond to whatever weight would be required to advance the leading end portion of the ribbon over the roller P and efiect takingup of the slack as before described, which is determined by applying test weights to the leading. end of the ribbon passing over the roller P free of the roller Z until enough weight thus applied will effect advance of the ribbon sufliciently to take up the slack. The load imposed by the weighted roller Z is then made to correspond to that of the applied test weight.

By the use of this invention in developing motion picture films the longitudinal strain on the film will be so slight as not to effect material stretch of the film, which is highly advantageous since such stretching interferes with proper registration of the film and causes distortion in the projected pictures. It has been found in practice that the strain imposed on a film to advance it in the fashion herein set forth may be less than a pull of one-half pound, since each of the driving rollers J, K, L, M, N, O, and P acts to move only the short portion of the length of the film leading from the preceding roller, which pull is insuificient to effect stretching of the film. This slight pull is also such as to reduce the frictional contact of the feeding rollthe roller P out of driving relation to the film so that the leading portion of the film passing over any of the feeding rollers will be slackened sufficiently to reduce its frictional engagement with the feeding rollers to such extent that the latter will cease to effect advance of the leading portion of the film. The take up reel 12 will then act to take up the slack in the leading portion of the film until the tension thereon is suificient to cause the belt !6 to slip on the pulleys Iii-I1, thus terminating pull of the ribbon through the machine. The pull of the reel i2 is insufiicient to place the ribbon under such tension over the roller P as to cause the latter to effect any driving action on the ribbon. The operator then elevates the carriage and connects the severed ends of the film together by splicing in the usual manner all of which may be accomplished without stopping the motor 23.

An important feature of the invention resides in the compensation for longitudinal expansion and contraction, or stretch and shrink, of the film due to the wetting and drying of the film as it passes through the machine; this compensation being afiorded by reason of the nonpositive engagement of the film with the feeding rollers, since the expansion of the film on wetting thereof in causing an elongation of the 'film places a slack therein which is taken up by the feeding roller preceding which such slack occurs in the fashion insuflicient to cause breakage or tearing of the film under treatment. However in event of separation of the film at any point between the end rollers J and P, a slack will be formed in the film as before described.

Shrinking of the film in the drying chamber H places no undue strain on the film since the friction drive afforded between the rollers P and Z permits variable longitudinal shifting of the film relative thereto in event of a pull being imposed on the film in excess of the tractive efiort applied thereto by the feed roller Z.

While I have shown and described a specific embodiment of my invention I do not limit myself to the exact details of construction and arrangement shown but may employ such modifications in the parts and in their arrangement as occasion may require, coming within the meaning and scope of the appended claims.

I claim:

In a ribbon feeding mechanism a horizontally extending elongated carriage mounted for vertical movement, a ribbon feed reel on one end of said carriage, a ribbon take-up reel on the other end of said carriage, a plurality of feeding rollers mounted on said carriage and spaced apart longitudinally thereof around which a ribbon leading from the feed reel to the take-up reel is passed, guide means depending from said carriage adjacent the end portion thereof carrying the feed reel, a vertically movable carriage engaging said guide means, means for adjusting said last named carriage relative to the first named carriage, direction rollers on said second carriage around which a length of ribbon extending between a pair of adjacent rollers is passed, a plurality of hangers depending from said first named carriage, direction rollers on said hangers around which lengths of the ribbon extending between adjacent feeding rollers is passed, means on said first named carriage for collectively driving said feeding rollers, and means associated with said last named means for rotating said take-up reel.

HUGH H. GWYNNE.