Патент USA US2407239код для вставки
~ sept. 1o, 1946; 2,407,239 A. J. ALBRECHT FRICTION DRIVE FOR WEB PROPELLING ROLLERS Filed oct. 9, 1942 3 SheetsfSh‘egt 1_ Sept l0, w46@ A. J. ALBRECHT 2,4075239 FRICTION DRIVE FOR WEB PROPELLING ROLLERS , - Filed oct.4 9, 1942 " 3 Sheets-Sheet 2 ATTORI/VFY Sept» l0, 1946- A. J. ALBRECHT 2,407,239 ,FRICTION DRIVE FOR WEB ¿PROPELLING ROÍI'JLIÍÍRSl Filed 001'.. 9, 1942 Y 3 Sheets-Sheet 5 15;; w _8f @0^ 0^/ ¿ä 555 57 55 ‘97 635 ' E.; E ¿j Ó? / ` INVENTOR. -» Meana/»0m ¿ju @lßßfceoê/Uj Patented Sept. 10, 1946 2,407,239 ’ UNITED NSTATES PATENT OFFICE FRICTION DRIVE FOR WEB PROPELLING , ROLLERS ‘ , Alexander J. Albrecht, West New York, N. J., as signor to R. Hoe & Co., Inc., New York, N. Y., a corporation of New York Application October 9, 1942, Serial No. 461,477 (ol. avi-2.3) ' This invention relates to web-propelling and folding rollers for use in printing machines, and more particularly to an improved slip clutch or drive mechanism for yieldingly driving a rotat able web or sheet engaging member from a posi tively driven rotary drive. In propelling and folding webs or sheets of paper or other fiexible‘material in modern print ing machines, it is highly advantageous to em 2 a normally flat relatively thin, spring ring sur rounding the shaft and engaging the friction member, and a nut adjustable on the shaft and engaging the spring ring to exert force there against, to bias the friction member axially `into engagement with the driven member and thereby yieldingly rotate the web engaging member. An additional object of this invention is to provide an improved friction drive vor clutch for ploy rollers herein referred to as web engaging 10 web propelling or folding rollers for use in print rollers which have frictionally driven components ing machines, each roller including a rotatable or radially yieldable frictionally driven compo shaft, a friction member rotatable with the shaft nents which engage the Webs or sheets, vsaid com and movable axially thereon, a rotatable web en ponente being yieldably driven so that their pe gaging member or roller supported by the shaft, ripheral speed will conform to the linear speed a rotary positively driven member supported by of the engaged webs or sheets, independently of the shaft, a normally flat spring ring surround the operating speed of the drive. Such mecha ing the shaft and having a peripheral portion en nisms are disclosed in United States Patents of gaging the friction member, and an adjusting nut Fred Gitzendanner No. 1,827,359, granted October movable along the shaft and engaging the spring 13, 1931, and William` F. Huck No. 2,291,627, 20 ring to exert pressure thereagainst, to bias the granted August 4, 1942. l > l friction member into frictional engagement with It is, therefore, an object of this invention to the driven member and thereby yieldingly rotate provide an improved drive or clutch for web pro the web engaging member so that the peripheral pelling, nipping or folding rollers for use in print speed of theweb engaging member conforms to ing machines in whichwebs and sheets that may , the linear speed of the engaged web. be cut from webs are propelled through the ma It is also an object of this invention to provide chine, and in which the improved clutch friction a roller and drive of generally improved con ally connects a positively driven rotary drive with struction, whereby the device Will be simple, du a rotary web engaging member to yieldingly drive rable and inexpensive in construction, as well as the web engaging member so that the peripheral 30 convenient, practical, serviceable and efficient in speed of the web engaging member conforms to its use. ` the linear speed ofthe engaged Web or sheets.r With the foregoing and other objects in view, Another` object of this invention. is .to provide which will appear as the description proceeds, an improved friction drive or clutch for web pro the invention resides in the combination and ar pelling or folding rollers for use -in printing ma 25 rangement of parts and in the details of con chines, each roller including- a rotatable shaft, a struction hereinafter described and claimed, it friction member `rotatable with the shaft and being understood that various changes in form, movable axially thereon, a rotatable web engag proportion and minor details of construction may ing member or roller supported bytheshaft, a be made within the scope of the. claims without rotary positively driven member supported i by 40 departing from the spirit or sacrificing any ad the shaft, and means supported by the-shaft for vantages of the invention. biasing the frictio-n member into engagement with For a complete disclosure of the invention, a the driven member to thereby yieldingly drive detailed description thereof will now be given in the web engaging member, the said bias-impart connection with the accompanying drawings ing means being constructed and arranged to forming a part of the specification, wherein: occupy the minimum axial space relative to the Figure 1 is a partly sectional view in a hori zontal plane, and depicting improved web pro A further object of this invention is to provide pelling or folding-off rollers for use in a printing an improved friction drive or clutch` for >web pro machine; pelling or folding rollers for use `inprinting ma Figure 2 is a vertical sectional View taken on chines, each roller including a rotatable shaft, a the line 2-2 of Figure 1, and diagrammatically shaft. i i ' Y , , friction member rotatable withgthe shaftV and depicting the cooperable relationship between the improved folding-off rollers and the conventional folding cylinder of a printing machine; positively driven member supported by the shaft, 55 Figure 3 is a fragmental longitudinal sectional movable axially thereon, a rotatable web engaging member or roller supported by the shaft, a rotary 2,407,239 3 4 view depicting a slight modification in a compo nent of the folding-off roller; its inner edge engages the annular flange 3S of the slidable collar 25 which forms a seat for it. Figure 4 is a vertical sectional view taken on The adjusting nut 3l is normally held against the line 4-4 of Figure l. Figure 5 is a fragmental longitudinal sectional View, parts appearing in elevation, depicting mod rotation relative to the shaft I5 by means of plungers 36, which are slidably movable in ra dially-extending apertures 31 formed in the nut. ified web propelling or nipping rollers; and Each plunger 35 receives a helical extension Figure 6 is a fragmental longitudinal sectional View taken through an improved web propelling spring 38 therein, and the outer end of each or drag roller of a printing machine. spring engages a flat portion 4i] formed on a re 10 taining pin 4I, so that the beveled inner end of each plunger 36 is yieldingly forced into engage ment with axially-extending grooves 42 cut in the shaft I5. Each pin 4l is received within a cylin parts, there is depicted, in Figures l and 2, .co drical >aperture 43 formed in the nut 3i, and also acting folding-off or nipping rollers II), which cooperate with a conventional folding cylinder 15 in a_longitudinally-extending recess 44 formed in the outer end of each plunger 35 to hold the Il, which is diagrammatically depicted in Fig plunger against rotation, so that the beveled in ure 2, to receive sheets therefrom, and to fold ner end of each plunger will be disposed parallel them transversely, in conformity with the usual with the grooves 42 in the shaft I5. By this ar practice well understood by those skilled in the art. A conventional folding blade I2, operably 20 rangement the nut 3| is held in any selected angular position relative to the shaft I5, for a supported by the folding cylinder II, tucks the reason to be hereinafter explained. Although sheets carried by the folding cylinder to a point the nut 3l is normally held against rotation on between the coacting folding-off rollers I5 where the shaft I5,- it may be rotated relative thereto the sheets S are folded transversely. Finally the sheets are fed or propelled to the conventional 25 by applying suflicient turning force to the nut to overcome the restraint of the yieldable plungers delivery mechanism, not shown. 36; therefore the nut 3| is preferably provided Each improved folding-off roller I@ includes with holes 34 for the reception of a Spanner a shaft I 5 which has its terminals rotatably sup wrench, not shown, in order that the wrench ported in bearings carried by the machine frame I1, which bearings may be of any preferred type. 30 may be employed to rotate the nut against the restraining action of the plungers. |As the nut In conformity with general practice, it is desirn 3l rotates, its threads move longitudinally along able that at least one of the rollers Iß be sup the threads of the shaft l5, so that the longitu ported in yieldable bearings in order to prevent dinal position of the nut on the shaft may be ad damage to the machine in case of a choke. As herein shown, the shaft I5 of one of the rollers 35 justed to exert the required force on the periph eral portion of the spring ring 35, for a purpose Ill is supported in blocks I6 each fitted to slide to be hereinafter given. in an aperture in the frame I1, and these blocks Two roller rings or bearers 45 are located ad are each pressed by a spring I3 to yieldingly hold jacent each terminal of the shaft I5, and each it in one end of the aperture. The other shaft I5, as herein shown, is supported in bearing bush 40 bearer is T-shaped in cross section to provide a widened peripheral portion 46 and an inwardly ings ISa each of which in turn is carried by an projecting flange 41. The annular faces of the eccentric bushing I4, rotation of which permits flanges 41 of the bearers 45 engage flat annular adjustment of the separation of the rollers Ii) bearing or friction rings 46 which are secured to to provide for variation in thickness of the prod the fixed and slidable collars 2! and 25. The ucts passing between them. Each shaft I5 has rings 48 are preferably formed of bronze or other a pinion I8 keyed or otherwise secured thereto, suitable wear-resisting material. Although the and these pinions intermesh so that both shafts two bearers 45 are preferably provided at each I5 rotate in unison. Any suitable means may be end of each composite folding-off roller, it is to employed to drive the pinions I8, and in the pres be understood that any desired number of bearers ent arrangement there is depicted a gear 20 may be used. which meshes with one of the pinions I I5, and this A spacing sleeve 50 surrounds the shaft I5 in gear may be driven by any suitable drive com termediate the bearers 45 of each paii` of bear ponent, not shown, of the machine. ers, and each sleeve 50 has bearing or friction Each shaft I5 has a ñxed collar 2| threadedly 1A rings 48 secured to its faces, which rings engage secured thereto adjacent one terminal, as indi the flanges 41 of the bearers 45. l cated at 22, and the collar 2l is held against ro A plurality of sleeves 52 are supported on the tation relative to the shaft by a set screw 23. A shaft I5 between the inner bearers 45, and the slidable collar 25 surrounds the shaft I5 adjacent sleeves 5I) and 52 are mounted for free longi its opposite terminal, and although this collar is tudinal movement 0n the shaft I5, but they are free to slide longitudinally along the shaft, it is held against rotation relative thereto by pins 26 held against rotative movement relative thereto which are received in apertures formed in the by pins or keys 26 which are received within sleeves 50 and 52, and their rectangular heads 21 apertures formed in the collar. Each pin is pro are received within the keyways 23. The outer vided with an enlarged rectangular head 21 which is slidably received in a keyway 28 formed -.', face of each outer sleeve 52 has a bearing or friction ring 48 secured thereto, and these rings in the shaft I5. The outer face of the slidable engage the flanges 41 of the inner bearers 45. collar 25 is provided with a flange or projection Any preferred number of sleeves 52 may be pro30, which cooperates with components of the de vided for each composite roller, and the end vice hereinafter disclosed. face of one sleeve abuts the end face of the ad An adjusting nut 3l is threadedly secured to jacent sleeve to thereby space the bearer rings the shaft I5, as indicated at 32, and a flange or 45 a predetermined distance apart. The sleeves projection 33 extends inwardly from the periph 5I) and 52 have recesses 53 formed in their pe eral portion of this nut. This flange 33 engages ripheral portions in order that the conventional and forms a seat for the outer edge of a flat Referring to the drawings, in which similar reference characters designate corresponding spring ring 35, which surrounds the shaft I5, and sheet-holding pins 5I, diagrammatically indicat~ t ~ 2,407,239 5 ed in Figure 2, may freely pass the folding-pff rollers during the operation of the machine. The operation and function of the pins 5I are well known and understood by those skilled in the art, consequently therdiagrammatic illustration 6 spring ring is very small, and additlonalloading is evenly distributed over the loading members. If a helical spring is employed, the loading of the friction member is uneven due to the diiiiculty of forming the spring terminals so that they are accurately perpendicular to their axes, and be cause irregularities at the dead ends of these is sutûcient for this application. The` outer diameter of each bearer 45 is slight ly greater' than the outer diameter of the sleeves springs localize the load and cause uneven load 52, and the inner diameter of each bearer 45 ing. When a plurality of helical springs are em is somewhat greater than .the diameter of the 10 ployed, they are not usually uniform and conse shaft I5, so‘that the bearers are supported on \ the shaft in floating relation, for a purpose to be hereinafter set forth. - quently impart unequal forces which prevent their proper functioning. Although a number of sleeves are preferably~ The degree of adjusting movement of the nut employed in rollers of this character, it is to be 3| may be readily determined by a calibrated 15 understood, of course, that a single sleeve may arrangement which includes a scale inscribed on ‘ >be'interposed between the inner bearers 45. the periphery cfa projection 55 which extends In some instances, it is desirable to provide the axially from the nut 3 I. 'I'he scale includes num adjusting mechanism at each end of each roller bered graduated lines or marks 55 arranged to I5, so that more tension may be imparted to the register with an index 5'I inscribed on the shaft 20 bearers 45 at one end of the roller It) than at the I5. By this arrangement, the nut 3| may be other, In such arrangement, the sleeve 52‘1L (Fig readily adjusted to any selected angular posi ure 3) is securely locked to the shaft by a set tion with relation to the shaft I5. screw 54, or other suitable securing means. In the operation of the improved folding-off Again a single sleeve may be positioned between rollers I0, the cooperating bearers 45 of the op 25 the inner bearers 45, and locked to the shaft I5 posed folding-off rollers engage the sheets S and in a manner disclosed in Figure 3. propel them from‘the point of delivery` by the A modiñed form of the invention is depicted folding `blade I2 past the bite of the bearers 45, in Figure 5, in which the invention is incorpo where the sheets are folded, and then deposit rated in web propelling or nipping rollers 59 usu the sheets on a conventional conveyor, not shown.A 30 ally employed in printing machine folders below Inasmuch as the bearers 45 are of greater diam the conventional former, the use and function eter than the folding-off rollers, these bearers are of such rollers being well understood by those constantly forced `into engagement with the skilled in the art. l sheets, irrespective of the thickness of the prod Each roller 59 includes a driven shaft I5a which uct. The folding-olf rollers are preferably ad 35 has a cylindrical sleeve EI) rigidly secured there justed so that the outer periphera1 faces of the to by a set screw 6|, which is threaded through sleeves 52 are positioned close to the sheets, and, a laterally enlarged flange or head E2 formed in this> position, the bearers 45 are forced by at the inner end of each sleeve 60. In the pre their engagement with the sheets to a position ferred arrangement, a sleeve 60 is positioned ad~ of'eccentricity relative to the shafts I5, but this 40 jacent each end of the shaft I5a, and a tubular action is resisted by the frictional engagement body member 63 is carried by the shaft between between the flanges 4'I,of the bearers 45 and the f the spaced sleeves 60, and the member 63 is` coacting friction rings ,48, and thus, by rotation suitably secured to the shaft I5a so that it roi of the rollers, the product is constantly and firm tates therewith. `Inasrnuch as both ends of each ly engaged by the coacting bearers. 45 roller 59 are similar, only one end has been illus trated. spaced rings or collars 55 are supported The use of the relatively thin flat spring rings 35- permits the employment of any number of on a cylindrical surface 66 of the sleeve 60 for rings without greatly increasing the space re longitudinal sliding movement, but each collar quired. By this arrangement, any desired pres 65 is held against rotation relative to the sleeve sure may be exerted against the movable collar 50 50 by a pin 25 which is received within an aper 2s by simply rotar-,ing the adjusting nut 3|, which ` ture formed in the sleeve B0, and its enlarged rectangular head 2'I is received within a keyway rotation is permitted by the yieldability of the securing plungers 36. l 61 formed in the collar. A bearer 45e surrounds the peripheral surface 66 of the sleeve 5U and is The use of a plurality of flat spring rings per mits-choice of the number of spring rings best 55 `positioned between the collars 55, with the inner suited to produce the required pressure desired. faces of the collars 65 frictionally engaging the This is not possible when helical springs are em outer faces of the bearer 45a. Each inner collar 65 is provided with an annular projection I6B ployed, because similarly disposed helical springs in axial alignment obviously would not produce which engages a face 59 formed on the head 62. the requisite pressure. The flat spring ring also 60 Each outer collar‘65 is provided with a similar projection 68‘1` which is engaged by the inner por~ has characteristics which give a relatively con stant percentage of change of load for a given tion of a ñat spring ring 35, and the outer portion of the spring ring 35 is engaged by the projec increment of deflection at any point within the Vtion 33au of an adjusting nut SI5, substantially deflection limit, thus facilitating adjustment at both heavy and light loads. In the use of coil 65 similar to the nut hereinbefore described. YIn this arrangement, each adjusting nut 3| a or helical springs, a given change in deflection anywhere within the deflection limit gives a con~ may be rotated in the manner hereinbefore de stant change in load and, consequently, the sensi scribed, to adjustably move the nut longitudin tivity of adjustment is lost at light loads. The nally with relation to the sleeve 60 to thereby load capacity of a fiat spring ring is relatively 70 exert the requisite force on the outer portion of high, considering the small space required for its the spring 35, and the spring 35, in turn, imparts employment. In a spring of this type the load pressure to each outer collar 65, so that each is distributed more uniformly over the friction bearer 45a is frictionally engaged by the collars imparting members, because the load required to 65. The outer diameter of the bearers 45*i is straighten out any initial irregularities in the 75 somewhat greater than the outer diameter of the 2,407,239 7 8 conforms _to the linear speed ofthe web. In pro pelling different numbers of webs, the degree ‘of torque imparted to the roller is varied to conform b'ody member 63 and collars et, and the inner diameter.` of the bearers 45a is sufficiently greater than the diameter of the cylindrical portion of to the required drag or torque pull, and the degree the sleeve fit», so that 'the opposed yieldable fric tionally-held bearers d5“ of a pair of nipping Cn of torque may be readily controlled by adjusting the nut 3 ib to impart the desired force to the rollers 59 will coact to engage webs W running spring rings 35 to thus cause the springs to exert between the coacting nipping rollers as 'hereini the requisite pressure on the slidable collar 65". before described, to thus propel the webs. In the rarranfïements herein disclosed, duplicate The degree of adjusting movement of the nut ¿ilF~ may be readily determined by inscribing a 10 rollers simultaneously engaging the opposite sides of the web are shown, although under certain con calibrated scale 551 on the nut 3E“ for registra tion with an index mark 5"! inscribed on the outer collar 65, in a manner hereinbeiore dis ditions satisfactory operation can be obtained by the use of a solid roller engaging one side of the product, and a roller of one of the forms herein closed. In Figure 6 there is depicted a drag roller for 15 shown engaging the opposite side of the product instead. It will be understood that the invention may be former, and this roller includes a shaft ibi’ embodied in other specific forms without depart which has a roller body ßâb rigidly secured there~ use in a printing machine over a conventionalv ing from the >spirit or essential attributes thereof, tc, and the shaft is rotatably supported by anti 'friction bearings 'lû carried by side members 'il 20 and it is therefore desired that the present em bodiment be considered in all respects as illus of the machine frame, and the bearings are re» trative and not restrictive. tained in their operable position by bearing re~ What I claim is: tainer members. 'l2 and spacing rings "e3 and lb. l. In a material propelling roller for printing or Similar bearings it are provided at each end of the shaft i512 but inasmuch as these bearings are alike only one end of the shaft is shown. The terminal portion cf the shaft at .its drive end is reduced, as indicated at l5, to supF pci-’t thereon a sleeve fit1’. The sleeve ë‘ilb is held against axial movement on the reduced portion 30 secured retaining "i3 of the to washer shaft the terminal between 18. The of athe retaining shoulder shaft by washer 'il a and screw i9, cr other suitable securing device, and the sleeve E0" is held against rotatie-n relative to the folding machines, a rotatable shaft, a rotary ma terial engaging member supported by and rotat able with the shaft, a sleeve rotatable with the shaft and having a friction face, a driven member rotatable about the sleeve and having a friction surface, a friction collar supported relative to and rotatable with the shaft and movable in the direc tion of the axis of the shaft, an adjusting member supported relative to the shaft and movable in the direction of the axis of the shaft, and a flat spring ' ring normally disposed entirely in a plane per shaft EE" by a key 8i. The sleeve Gâb is provided with a flange 62h at its inner end, having -a pendicular to the axis of the material engaging member and surrounding the shaft and operably interposed between the adjusting member and the collar whereby axial movement of the adjusting clutch face 8G which frictionally engages a clutch surface 85 formed on the inner face of a gear 86, which is rotatably supported on the sleeve btb. 40 member causes the spring ring to bias the collar A collar or ring 55h is mounted for longitudinal for movement towards the said friction face to movement on th sleeve Elib, but this collar is held thereby press the driven member between the against rotative movement relative to the sleeve collar and the friction face and yieldingly drive GGD by a hey 8l, or other suitable securing device. the material engaging member when the driven The inner face of the collar 65h engages the outer member is rotated, the adjusting member engag ing the spring to constantly bias the spring face 88 of the gear 86, so that it is frictionally en gaged on each side. The gear Bt is provided with teeth ëê which mesh with similar teeth on a drive gear convenient not shown, drive which component may of be the driven machine. from An annular projection 53h extends outwardly from the collar 55", and engages the inner portion of a flat spring ring 35. This spring ring is, in this instance, disposed in face to face abutting relation with a second similar spring ring, and the outer portion of the second ring is engaged by an against the collar and the degree of constant bias of the spring against the collar being determined by the degree of adjusting movement of the ad Ci justing member. 2. In a material propelling roller, a rotatable shaft, a material engaging member carried by and rotatable with the shaft, a sleeve secured to and supported by the shaft and having a flat wi clutch face, a driven member having opposite clutch faces and rotatably supported by the annular projection 33h which extends inwardly sleeve, a collar rotatable with the sleeve and from an adjusting nut 3Ib, substantially similar to the adjusting nuts hereinbefore described. In operation, the engagement of the clutch faces 85 and 88 of the gear 86 with the clutch face S0 slidable axially thereon, an adjusting 'member and clutch face of the collar 551’ causes the gear entirely in a plane perpendicular to the axis of the material vengaging member and surrounding the sleeve and operably interposed between the adjusting member and the collar to bias the co1~ lar for axial movement towards the said flat clutch facev to frictiorlally connect the driven member with the sleeve to thereby yieldingly ro tate the shaft and material engaging member, the adjusting member engaging the spring to constantly bias the spring against the collar and the degree of constant bias of the spring against the collar being determined by the degree of ad justing movement of the adjusting member. 3. In a material propelling roller, a rotatable 75 86 to drive the shaft lâh and roller 53D until a pre* determined resistance is exerted on the roller 53h, and then the gear will slip to permit the roller to conform to the speed of the web Wb which is wrapped about the roller body 63", in conformity with the usual practice in guiding and propelling webs through a printing machine. By this ar rangement the roller body'fââb may exert suûicient torque pull or “drag” on the web to propel or feed itl but the torque imparted to the roller body 63h will not be suñicient to cause the roller to slip or move relative to the web, so that the peripheral speed of the roller, as hereinbefore stated, always threadedly secured to the sleeve and movable ax ially along the sleeve when rotated relatively thereto, and a flat spring ring normally disposed 9 2,407,239 shaft, a material engaging member carried by and rotatable with the shaft, a sleeve supported by and secured to the shaft and having a iiat clutch face, a driven member having opposite 10 operably interposed between the' adjusting mem ber and the collar to bias the collar for axial movement towards the said driven member to frictionally engage the clutch faces of the sleeve ‘and collar with the clutch faces of the driven member to thereby yieldingly rotate the shaft clutch faces and rotatably supported by the sleeve, a collar rotatable with the sleeve and slid able axially thereon, an adjusting member and material engaging member, and means for threadedly secured to the sleeve and movable axi securing the adjusting member against uninten ally along the sleeve when rotated relatively tional rotation relative to the sleeve, the adjust thereto, and a flat spring ring normally disposed 10 ing member engaging the‘spring to constantly entirely in a plane perpendicular to the axis of bias the spring against the collar and the degree the material engaging member and surrounding of constant bias of the spring against the collar the sleeve and operably interposed between the being determined by the degree of adjusting adjusting member and the collar to bias the col movement of the adjusting member. lar for axial movement towards the said flat 15 5. In a web propelling roller for a printing ma clutch face to frictionally connect the driven chine, a rotary material engaging member adapt member with the sleeve to thereby yieldingly ro ed to propel the engaged web, a rotary driven tate the shaft and material engaging member, member, a rotary and slidable collar, a movable and yieldable means for securing the adjusting adjusting member, and a slidable ñat spring ring member against unintentional rotation relative 20 normally disposed entirely in a plane perpendicu to the sleeve, the adjusting member engaging the lar to the axis of the web engaging member and spring to constantly biasl the spring against the operably interposed between the adjusting mem collar and the degree of constant bias of the ber and the collar and operably engaged by the spring against the collar being determined by adjusting member and collar respectively ad the degree of adjusting movement of the adjust 25 jacent its outer and inner peripheral edges to ing member. bias the collar for movement to frictionally conn 4. In a material propelling roller, a rotatable nect the driven member and web engaging mem shaft, a material engaging member carriedlby ber and yieldingly drive the web engaging mem and rotatable with the shaft, a sleeve supported ber, the adjusting member engaging the spring by and secured to the shaft and having a clutch 30 to bias the spring against the collar and the de face, a driven member rotatably supported by gree of bias against the collar being determined the sleeve and having opposite clutch faces, a by the degree of adjusting movement of the ad collar supported by and rotatable with the sleeve justing member from normal flat condition of the and slidable axially thereon, the collar having a spring to a deflected condition Within the elastic flat clutch face, an adjusting nut threadedly l limit of the spring, the spring having a relatively secured to the sleeve and movable axially along constant percentage of change of load for a given the sleeve when rotated relatively thereto, a fiat increment of deiiection at any point Within the spring ring normally disposed entirely in a plane range of deñection adjustment. perpendicular to the axis of the material engag ing member and surrounding the sleeve and 40 ALEXANDER J. ALBRECHT.