US2814486A - Web feeding apparatus - Google Patents

Description

Nov. 26, 1957 G. M. GURLEY ETAL 2,814,486

WEB FEEDING APPARATUS 2 Sheets-Sheet 1 Filed Dec. 31, {L954 E m V E D INVENTORS GREY M GURLEV FRED M. CARROLL g Y ATTO N5! Nov. 26, 1957 G. M. GURLEY ETAL I 2,814,486

WEB FEEDING APPARATUS Filed Dec. 51. 1954 2 Sheets-Sheet 2 28 2 M "ilmlllilllljfi A M "FIG-g 3.

IN V EN TORS GREY M. GURLEY FRED M. CARROLL United States Patent WEB FEEDING APPARATUS Grey M. Gurley, Endwell, and Fred M. Carroll, Binghamton, N. Y., assignors to International Business Machines Corporation, New York, N. Y., a corporation of New York Application December 31, 1954, Serial No. 479,146

1 Claim. (Cl. 271-23) The present invention relates to web feeding apparatus and particularly to a variable feed device which maintains a substantially constant web tension to a pair of main feed rolls.

In the manufacture of tabulating cards it is standard practice to mount a reel of paper stock in web form on a printing machine. The free end of the web is normally threaded over a number of idler rolls and web straightening apparatus and through pairs of main feed rolls, printing rolls and cutolf rolls. Individual cards are produced from the cutoff rolls and supplied to a drier wheel and from there to a stacker. The main feed rolls, the printing rolls and the cutoff rolls are all timed from the same machine drive and each pair completes a single revolution in the same time interval. The web stock from which tabulating cards are produced varies in thickness within the same reel and also from one reel to another. With a predetermined setting of the main feed rolls, different rates of web feeding will result due to the variation in thickness. When the Web is relatively thick the feed rolls can get a better grip on the web than when the web is relatively thin. Thus, there may be slippage on the thin web. Another cause of varying rates of feed by the main feed rolls is due to the change in reel size from the beginning ot the end of a run. Thus, at the beginning of a run the reel is larger and the feed rolls must work harder to feed the web than when the reel is small near the end of the run. This means that the tension of the web supplied to the main feed rolls varies from the beginning to the end of a run. If at any time there is a variable rate of web feed while the drive to the main feed rolls and cutoif rolls is constant, the length of the cards produced will also vary. This causes poor registration of the printing on the card from the print rolls and is even more serious for the various computing and accounting machines which must process these cards. This is due to the fact that the machines which perforate the cards to place data therein may use a different end of the card for registration purposes than the machines which sense the data. If the card length is incorrect, the perforations will not be properly registered and may produce erroneous data.

The present invention overcomes the difficulties described above by providing a variable drive but substantially constant tension web feed device ahead of the main feed rolls so that the main feed rolls provide a substantially constant rate of web feed. Briefly, there is provided a positively driven rubber roll and an eccentrically mounted idler roll between which the web passes on its way to the main feed rolls. The pressure applied to the web by the rubber and idler rolls is determined by a sensing arm having one end secured to the shaft which controls the eccentricity of the idler roll and the other end arranged to detect the tension in the web. If the tension decreases, the centerlines of the rubber and idler rolls are moved further apart and if it increases, the said centerlines are moved closer together.

Therefore, the present invention has as one of its objects the provision of web feeding apparatus which supplies a substantially constant tension web to the main feed rolls.

Another object of the invention is to furnish a web feeding apparatus which feeds the web at a variable rate and at a substantially constant tension to a web processing apparatus.

A further object of the invention is to furnish web feeding apparatus as described in the paragraph immediately above where the web processing apparatus includes means for feeding the web at a substantially constant rate of feed.

Other objects of the invention will be pointed out in the following description and claim and illustrated in the accompanying drawings, which disclose, by way of examples, the principle of the invention and the best mode, which has been contemplated, of applying that principle.

In the drawings:

Fig. 1 is a schematic diagram of the web feeding apparatus of the present invention and its association with the print rolls and cutoff rolls;

Fig. 2 is a side elevation of the variable feed device of the present invention; and

Fig. 3 is a sectional view taken on lines 3-3 of Fig. 2.

Similar reference numerals represent similar parts throughout the several views.

As shown in Fig. 1, the web passes through the constant tension-variable feed device of the present invention to the main feed rolls. From the main feed rolls the web passes between the print rolls and the cutoff rolls. Reference is now made to Figs. 2 and 3 which show details of the constant tension-variable feed device. The frame member of the press upon which this device is mounted is illustrated by reference numeral 10. The frame member is apertured as at 12 to receive a bearing 11, said bearing having a flange 13 thereon which is adapted to abut the side of the frame member. The flange is furnished with elongated apertures 14, 15 and 16 which receive screws 17, 18 and 19, respectively. The frame member is provided With suitable tapped bores to receive the screws. Bearing 11 is furnished with a slightly eccentric bore 20 which is adapted to rotatably mount a drive shaft 21. This shaft has a turned down end portion 22 which produces a shoulder 23. Axial movement of the shaft toward the frame is prevented by a collar 24 which is secured to shaft 21 by set screw 25. A rubber driving roll is received by the turned down end portion 22 of shaft 21 and is secured thereto by a nut 27 which is received by threads 28 on said end portion. The rubber driving roll has a metal inner sleeve 28 which abuts shoulder 23 and one side of a washer 29, the other side of said washer engaging nut 27.

'It will be noted that the lower portion of flange 13 has a rack 30 which is engaged by pinion 31. This rack and pinion arrangement is used to position the center of rotation of rubber roll 26 to the right or left of the position shown. Thus, by loosening screws 17, 18 and 19, and rotating pinion 31, the flange as well as the bearing rotate. Since the shaft 21 is eccentrically mounted in the bearing, rotation of the bearing and flange cause the shaft center to move to the left or right, depending upon the direction of rotation. Once the proper position is attained, screws 17, 18 and 19 are tightened and the flange is rigidly secured to frame member 10.

A steel pressure roll 32 is operatively associated with the rubber roll 26 so as to be driven therefrom. The web 33 is shown to extend partly around roll 32 and then between rolls 26 and 32. The web then engages an idler roll 34 and a shoe 35 before going to the main feed rolls. The pressure roll 32 is furnished with suitable internal bearings 36 and 37 which rotatably mount the roll on a shaft 38. This shaft has shoulders 39 and 40 which engage 'the inner sides of bearings 36 and 37, respectively.

Retaining members 41 and 42 are secured at opposite ends of roll 32 by suitable means and are arranged to engage the outer sides of bearings 36 and 37, respectively. Shaft 38 has eccentrically mounted stub shaft ends 43 and 44 which are mounted by means of bearings 45 and 46, respectively, within apertures47 and 48, respectively, in spaced frame members 49 and 50, respectively. Frame member 50 is secured to frame member 10 by means of stud bolts 51, 52 and 53 and has a projection 54 which engages frame member 49. This latter frame member is secured to the projection by means of a stud bolt 55 and screws 56 and 57.

While roll 32 is adapted to rotate with respect to shaft 38, angular motion of the shaft will move the center of rotation of roll 32 with respect to the center of rotation of roll 26. The present invention controls the angular motion of shaft 38 by means of an arm 58 having one end secured to shaft 38 by means of a stud bolt. The other end of arm 58 is utilized to mount a shaft 60 which journals the idling or sensing roll 34. A spring 61 conmeets the said other end of arm 58 to a bracket 62 which is secured to frame member 10. It is upon this bracket that shoe 35 is mounted.

The operation of the present invention will now be explained in detail. The positively driven rubber roll 26 is adjusted relative to roll 32 to a particular setting and screws 17, 18 and 19 are tightened. This fixes the position of the center of rotation of the rubber roll. Let it be assumed that the web is threaded through. the apparatus as shown in Fig. 1 and that the apparatus is in operation. Spring 61 normally urges roll 34 against the web. If the rate of feed of rolls 26 and 32 is too great, the tension of the web at the point Where it engages roll 34 will be less than the normal tension. This allows spring 61 to rotate arm 58 and shaft 38 counterclockwise so that the center of rotation of pressure roll 32 is moved away from the now fixed center of rotation of rubber driving roll 26. This means that roll 26 will apply less pressure to roll 26 and the web will be fed at a slower rate. If the rate of feed gets too slow, then the tension of the web moves arm 58 clockwise and thereby causes roll 32 to apply a greater pressure to the rubber driving roll. 26. This causes the rubber driving roll and the pressure roll to feed paper at a greater rate. The rubber roll 26 is slightly larger in diameter than each of the main feed rolls so that it is capable of feeding paper at a faster rate than the master feed rolls. Thus, it will be seen that the present invention maintains the paper at the entrance to the master feed rolls at a substantially constant tension by means of a variable feed drive. The variable feed drive is controlled by the variations from the substantially constant tension. The use of the rubber drive roll in combination with the pressure roll allows a relatively wide range of web feeding rate.

While there have been shown and described and pointed out the fundamental novel features of the invention as applied to a preferred embodiment, it will be understood that various omissions and substitutions and changes in the form and details of the device illustrated and in its operation may be made by those skilled in the art, without departing from. the spirit of the invention. It is the intention, therefore, to be limited only as indicated by the scope of the following claim.

What is claimed is:

A web feeding mechanism for supplying a continuous web from a web supply to master feeding means, a variable feed device comprising a driven roll and a driving feed roll between which said web passes, said web having more of its area in engagement with said driven roll than said driving feed roll, said driving feed roll being fixedly mounted on a drive shaft for rotation therewith and having a resilient outer surface, said driven roll being journaled on a shaft which is eccentrically mounted, an arm having one end fixed to the last named shaft and having a web engaging means mounted on the other end thereof, said web engaging means engaging the web after it leaves said driven roll but before it enters said master feeding means, and means for urging said web engaging means into engagement with said web so that the tension in said web between said driven roll and said master feeding means determines the rotational position of said last named shaft which thereby determines the movement of said driven roll toward and away from said driving feed roll.

References Cited in the file of this patent UNITED STATES PATENTS 1,235,805 Jennings Aug. 7, 1917 1,586,719 Swab June 1, 1926 1,826,495 Beck Oct. 6, 1931 2,119,670 Fitz Gerald June 7, 1938

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