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Resilient roll apparatus for working tenuous material

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US2870818A
US2870818A US46109054A US2870818A US 2870818 A US2870818 A US 2870818A US 46109054 A US46109054 A US 46109054A US 2870818 A US2870818 A US 2870818A
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Prior art keywords
rolls
material
housing
apparatus
upper
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Richard F Herr
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HERR EQUIPMENT CORP
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HERR EQUIPMENT CORP
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B21MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21DWORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21D1/00Straightening, restoring form or removing local distortions of sheet metal or specific articles made therefrom; Stretching sheet metal combined with rolling
    • B21D1/02Straightening, restoring form or removing local distortions of sheet metal or specific articles made therefrom; Stretching sheet metal combined with rolling by rollers

Description

Jan. 27, 1959 R. F. HERR 7 2,870,818

RESILIENTROLL APPARATUS FOR WORKING TENUOUS MATERIAL Filed Oct. a, 1954 v e Sheets-Sheet 1 INVENTOIL mcnnnn E HERR Zak W 7 Error/14y Jan. 27, 1959 R. F. HERR 2,870,813

v RESILIENT ROLL APPARATUS FOR WORKING TENUOUS MATERIAL Filed Oct. 8, 1954 s Sheets-Sheet u) a ii I INVENTOR. I N N RICH/7RD E HERE N 3 m BY m N 31 ww Httorney Jan. 27, 1959 R. F. HERR 2,870,818

RESILIENT ROLL APPARATUS FOR WORKING TENUOUS MATERIAL Filed obt. 8, 1954 s Sheets-Sheet 3 0 I. II I h n I co 1+ I I v u? no; \lllu 1 v) I I H I hl I .1: L Ii! \1 z j! I 1 2% ii N 92K;

WIIIIIIIIQEFIIIIIIIIIM Rfforney RESILIENT ROLL APPARATUS FOR WORKING TENUOUSMATERIAL Filed Oct. 8, 1954 6 Sheets-Sheet 4 Rtto may R. F. HERR RESILIENT ROLL APPARATUS FOR WORKING TENUOUS MATERIAL Jan. 27, 1959 6 Sheets-Sheet 5 Filed Oct. 8, 1954 INVENTOR. RICHHRD F HERR BY H'tforney United wam RESILIENT ROLL APPARATUS FOR WORKING TENUOUS MATERIAL Richard F. Herr, Warren, Ohio, assignor to The Herr Efquigment Corporation, Warren, Ohio, a corporation 0 0 io Application October 8, 1954, Serial No. 461,090 r 3 Claims. (01.153-104) The present invention relates to methods of and apparatus for working tenuous material, more particularly to methods of and apparatus for straightening strip material, and the principal object of my invention is to provide new and improved methods and apparatus of the character described.

Metal strip is usually transported and sold in coiled form from which it must be unwound by the user. Since coiled strip often acquires what is known ascoil set, it is frequently necessary to remove this coil set and straighten the strip before subsequent operations can be performed thereon.

Straightening apparatus, or levelers, have long been employed for this purpose and these levelers usually com-.

prise a plurality of rolls arranged to provide a tortuous pass through which the material is fed. The tortuous pass provided by theseprior art levelers bends the strip beyond its elastic limit first in onedirection and then in the opposite direction, the strip theoretically leaving the pass straight and flat.

In practice, prior art levelers have not been entirely satisfactory since they are very sensitive to strip thickness and require delicate adjustment of the leveler rolls in order to satisfactorily straighten the strip. The sensitivity of prior art levelers is so great that small variations in strip thickness from side-to-side or, end-to-end result in improper straightening. Moreover, manufacturingvariations in strip thickness from coil to coil frequently require readjustment of the leveler rolls to produce satisfactory results. l

My invention provides methods of and leveler apparatus for straightening strip without the disadvantages of prior art methods and apparatus. Other advantages will i become apparent from a study of the following descrip=- tion and from the drawings appended hereto.

In the drawings accompanying this specification and forming a part of this application there is shown, for purposeof illustration, anembodiment which my invention may assume, andin these drawings: t

,Figure -1 is a side elevational view of apparatus embodying my invention, a portion being broken away to illustrate interior construction,

Figure 2 is a broken, top plan view of the apparatus,

Figure 3 is a broken, side elevational view,

Figure 4 is a fragmentary sectional view generallymatic views illustrating an operating principle of my,

invention.

With particular reference to Figures 1, 2 and 3, it will be noted that the herein disclosed apparatus comprises -a pair of spaced-apart housings and 11 having a-plu-,

rality of rolls extending therebetween. The housings are rigidly secured to any suitable supporting surface by means of bolts 12. H

Housing 10 comprises a lower homing portion 10a and an upper housing portion 10b, while housing 11 comprises a lower housing portion 11a and an upper housing portion 11b. Lower housing portions 10a, 11a, rotatably support a plurality of lower leveler rolls 13 (herein shown to be four in number) which extend between the housings (see Figure 5) and which are disposed in side-by-side relation (see Figure 1). Upper housing portions 10b, 11b rotatably support a plurality of upper leveler rolls 14 (herein shown to be three in number) which are disposed between respective lower leveler rolls 13 (see Figures 1 and 4).

For a purpose later to be disclosed, each upper housing 10b, 11b is slideable vertically (in the position of parts shown) relative to its respective lower housing. As shown in Figure 1, lower housing10a has a pair of spaced-apart upstanding leg portions 15 which provide respective slide surfaces 16 (see also Figure 4). Upper housing 101: has a depending portion providing legs 17 having slide surfaces 18 which are slideable with surfaces 16. Secured to the outside of legs 17 by means of suitable capscrews or the like are gib plates 19 which overlie respective slide surfaces 16, 18. Although not shown ,in detail, housing portions 11a, lllb are similar to and-are slideable in the same manner as are portions 10a,,10b. .Gib plates 20 (see Figurel), similar in all respects to gib plates 19, are carried by housing portion 11b, the respective gib plates maintaining the upper housing portions in vertical alignment with respective lower housing portions.

{Asbest shown in Figures 1, 2 and 5, a pair of links 21, 22 arepivotally secured to and on opposite sides of each leg portion 15 of housing portion 10a. The lower end of each pair of links is pivoted to a respective leg portion 15 by means of a headed pin 23 (see especially Figure 5). Two. pair of links 24, 25 are also carried by housing portion 11a of housing 11, links 24 being similar to links21 and links 25' being similar to links 22.

With respect to the position of parts shown in Figure l, the upper ends of the links 21, 22 and 24, 25 disposed at the right-hand end of the apparatus are journaled on a. shaft 26 which extends between the upper housing portions 10b, 11b. Shaft 26 has spaced journal portions 27 (see Figure 5) which are eccentric to the axis of the shaft and which are rotatable within bearings provided by respective upper housing portions 10b, 11b. A collar 28 is secured to one end of shaft 26 and a sprocket 29 is secured to the other end of the shaft. A suitable handle 30 is secured to collar 28 to provide means by which'shaft 26 may be rotated Referring to Figures 1 and 2, it will be seen that the upper ends of the links at the left-hand end of the apparatus are journaled on a shaft 31 which is similar to shaft26. It is to be understood that shaft 31 has eccentric portions journaled in respective housing portions 10b, 11b in the same manner as is shaft 26. Shaft 31 has a sprocket 32 secured thereto and a suitable chain 33 extends between the sprockets carried by shaft 26, 31 to coordinate rotation of the latter.

As shown in Figures 2, 5 and 6, each link 22, 22 and 25, 25 is formed in two pieces held together by means: of screws 34. The upper end of each of these links is moving handle 30 in the direction of the arrow from the full line position shown in Figure 1'- to the dotted line position, the respective eccentric portions 27 of the respective shafts 26, 31 will simultaneously move the respe'ctivuppe'rhousing portions 105, lil b' 'i'ri ag direction" away from the lower housing portions for apurpose tribe disclosed. v i

'With particular reference to Figures 1-- and; 4, the upper rolls 14 are not carried directly" by the upperhousing portions but instead," eache'nd" of a rollf 1"41i's 'I rotatable in a chock 36 respectiyely'carried' by the upper housing portions 10b, 1 1b. As best shown in Figur'e" 1;; an "opening 3f7 is provided in each; upper housing'g por tion 10b 11b for. receiving "the checks 36. The sides -'f= opening-"37 are rabheted at 3'8 tojproyide'slide 'surfacesf' andthe pdrti'o'ns of the-respect'ive' chocks adjoining-the sides of the opening 37' arecorrespondingly grooved to interfit with the latter (see Figure 4) As shown in Figure '4'; a similar arrangementis employjedbetween the end-checks 36'and jthe"interme diate'choclg to provide interfitting slide surfaces therebetwe'enf With the c'on'i struction thus' far disclosed, it will be clear that-eachchock 36 is held 'to 'vertical'movement (relative-to the." position of-partsshown 'inFigure l)'toward and away from'the lower rollsIS. i Means areip'rovided' for adjusting each upper roll-14- relative to the fixed lower rolls 13} At the present time, each.chock 3"6fhasFa screw rod 39- threaded therein- (see Figure- 1 Each screw rod is 'carried by its respective upper? housing portion for rotation relative thereto but isfheld. against axi'al movement liy any suitable means." Eaclrscrewrrod 39 :has worm gear 40isecured-thereto andeachyyworni gearfis. operably engage'a'bl withI-a f worm. 41..whicnf. is. suitably; journaled ina-1 respective; upper: housing. i

At the present time it is preferred that opposite ends of? respectiverolls :14 be. moved; simultaneously Accordingl-y, the. worms. ll' which rotatethe screW-rodS com;

n'ecteda to, opposite ends. of each roll 14: are connected";

together-by. means of an adjusting'shaft'42 (see Figure 2 )1 In orde'r to eliminate any possibility .of binding shafts 42, suitable flexible couplings 43 are interposed in each shaft. The end of each' shaft 42 carried by housing por tion 10b extends .beyondgthe-housing' and is provided with wrench flats, 44-01; the. like to. facilitatevrotati on ofithe shafts In addition to, theleyeler rolls 13, .14; the, herein. disclosed apparatusis, provided with av'pairof: opposed pinch rolls which extendbetween the. housings 10' and ll' and which comprise atlo'wer pinch.- roll .46; and an p??? p nchr l 4.75...

Asbest shown in Figures 1;;and- 6,; lower pinch roll 46 is suitably. journaled in. the lower housing; portions 10a;- 11a while.v upper; pinehiroll; 47zispjournaled in checks; 8. respeetiyely.carried by the upperhousingtpo'rtions 10b, 11b. Each of the upper, housing. portions. isafor-med ith 5 .11.. psui sqwn av us sides.whichi'areerabheteds'at tPr vi e-sl e;surtacssmi htwhien re'spective.:. o ks= 8Z relisl ab e A tshcw rin F gure'..,4, .chiockst 48.1 are-n. grooved I to interfit wiih the; portions bfi the-respective? upset hous n s diae rt. the. opening, 4st .tO: hold t chocks to movement toward andaw ylfrom. the lower; pinch roll 46, 7

e s re P ov d usting-checks .48, tog ther... with 'pinch roll 47 carried the r eby, rela, c; totpinchz, r 11. 6.. t s-pr ter bleg t t qhend; of, roll; 4713196 d en n a ju ab e. 'acsqt ns n {a sep. ratet di st-;. ing mechanism iscarr ied by ea'c h up per honsingmortiont .51 1b c e dju ti .m sphe ismior. aehends of roll47isidentical, the: adjusting rnechanismat only,

one n will, be described in detail.

Referring to Figure 6, it will be seen that housing. pgr gn wbq armssigtqr endee.te e sfih t s qt yspeng @9, A threadedl ap erturep52 th; formedg in, hp u igg portion .101 concert ie. with recesszwsh this jam nut 59 holds nut 58 in its adjusted position on rod 571 Aeompre'ssion;springfit) i s interposed between the enlarged-portion"ofsleeve 53" and'chock 48; in order to spring-load the pinch rolls together. In the event an abnormally .l1e avy piece of. material. :ispfed. through the pinch rolls, the spring 6.0twill deflect to prevent damage to the apparatus. l i i i In setting up the apparatus, nut 58 is adjusted along rod 57 until spring 60 has been placed under the desired compression wherein the pinch rolls will-exert the desired amount ofwpressur ei- 'upon' material positioned therebetwe'nflammit- 59 will'th e1n be tightened against nut 58 to'hold thisadjustment; SI'eeVe SS will then be rotated (-nt'ilizin-g-thewrench flats on portion 55 ujntil the desired I spacing between the pinch rolls is achieved; Nut 56 willthen be tightened-against--h0usingportion 10b to hold the: sleeve inposition It will-be' understood that the other .end of pinch roll 47 carriedby housing ll-will be adjusted in a similarmanner;

Operationofi the invention thus far described will be as follows: Handle30 will be rotated from its fullline position shown in- Fi-gure- 1: to itsdot dash line position toxelevat'e the upperhbusing portions 10b, 11b and sepa:

ratepthe-upper and lowe'rleveler rolls and the upper and lower pinch rollsQ' The. stripmaterialto be straightened willnthenfbe fedbetween; the rolls (from leftto right; inathe-sposition.oflparts-shown in; Figure l the separated? rollsfacilitating: this operationeas will beunderstopda The handle 30 will then be returned to its original-posi tionetos-move-the uppenandiowe'r .rolls-togetli'er'as shown in- Figure l;

The) pinch-rolls 46, 47 will'then be rotated; by'any' suitable-ldrivei mechanism (not shown),-todraw the strip material. throughthe tortuouspass provided-by theupper and vlower sets;of leveler rolls. Assuming that eaeh ofi the; upper; leveler rolls l4-has beenproperly adjusted' relatiyeltothel owert leveler rolls 13, the strip will emerge from. .the: pinch: rolls 46, 47 in straightened form.

It is a feature of the present invention that the levelerrolls-r13 14-have resilient working-surfaces. In'the-herein disclosediernbodiment, each of the rolls-13, -14 has ailayer of; rubberdikamatei'ial 61 bonded or otherwise secured thereto. (seeFigures 7 and-8) As generally diagrammatically shownin Figure 7; the" strip. material. S; in passing between-the=- upper and-lower levelenrolls 13; 14,- is fiexed- -first'in one direction and them in the; opposite .directionan arnount sufficient to: stress the material beyond itselastic limitl- Although notshpwn ,theuppeiileveler rolls--areusuallysoadjustediela- I tive to. thefadjoiningilower--leveler rolls thatfthegstrip will;

be flexed progressively less as it-advancesthrough' the levelcr'rolls. i A 1 When relatively thin strip is passed'through the leveler rolls, asillustrated in Figur-e 7, the st rip will be flexed an amount indicated at X: For purpose of illustration, itsw-ill be assumed'that the amount of flexure indicated at X is sufficient to stress the relativelythin strip beyond its elastic limit. It is to be noted that little or nofsurface deflection of the-rollsoccu rs with thist hin inaterial' and that the respective; radii ofthe rQlls are substantially unchanged.

It is a well-known phenomenon that in order to irn part the, same predetermined set in -two pieces of similar material, one of whieh is tliiclt -and the other" of vvhich" istbim th m mst lf nr eet area-Fremont;

(i. e., through a greater distance or about a sharper radius).

As shown in Figure 8 and with the leveler rolls 13, 14 in the same adjusted position as they are in Figure 7, when relatively. thick material is fed between the rolls, the greater resistance to bending of the relatively thick material causes the resilient surface of the rolls to deflect. With the deflection of the surface of the leveler rolls, the material will be flexed an amount indicated at Y or about a greater radius than with thin material since the deformation of the rolls in working the thicker material has increased the effective radii of the rolls. Obviously, the amount Y that the thick material is flexed is materially less than the amount X that thethin material is flexed. However, because of the phenomenon hereinbefore mentioned, both the thick and thin material will be subjected to a substantially equal amount of stress.

It Will be appreciated that both the thickness of the resilient layer 61 and the type of material of which it is formed will be carefully proportioned to achieve the desired results. It will also be appreciated that with leveler rolls having a suitable resilient surface, my invention will straighten material of variable thickness without necessitating the time-consuming roll adjustments required by prior art methods and apparatus. Thus my invention automatically compensates for material varying in thickness from both end-to-end and/or side-to-side.

In order to reduce the possibility of marring the surface of the strip material handled by the present invention and to increase roll life, the pinch rolls 46, 47 also have resilient working surfaces which are similar to the working surfaces of the leveler rolls. However, it will be understood that the pinch rolls may have the usual inflexible working surfaces. Additionally, while I have disclosed apparatus having undriven leveler rolls which merely rotate in response to the tangential force which results as the strip is pulled therebetween by the pinch rolls, I may, if desired, drive one or more of the leveler rolls. In the event certain of the leveler rolls aredriven, it will be appreciated that the pinch rolls could be eliminated.

In view of the foregoing it will be apparent to those skilled in the art that I have accomplished at least the principal object of my invention and it will also be apparent to those skilled in the art that the embodiment -herein described may be variously changed and modified,

ciated that the herein disclosed embodiment is illustra tive only, and that my invention is not limited thereto.

I claim:

1. Apparatus for imparting a predetermined set to sheet material of varying thickness, comprising a plurality of rolls providing a tortuous pass through which the material travels, certain of said rolls engaging one side of the material and certain other of said rolls engaging the other side of the material and said rolls having deformable, resilient peripheral working surfaces in pressure contact with the material traveling through said pass to bend the material in one direction about the radii of certain of said rolls and in the other direction about the radii of certain other of said rolls to flex the material beyond its elastic limit, said pressure contact between the material and said rolls varying in accordance with material thickness and effecting temporary deformation of the peripheries of said rolls to respective arcuate shapes having radii larger than the initial, undeformed radii of said rolls, the radii to which the peripheries of said rolls are deformed varying in accordance with said pressure contact and automatically increasing with an increase in material thickness to reduce the amount that the material is bent and automatically decreasing with a decrease in material thickness to increase the amount that the material is bent to automatically impart said. predetermined set to the material despite variations in thickness thereof.

2. Apparatus in accordance with claim 1 wherein the rolls engaging one side of the material comprise one roll set and wherein the rolls engaging the other side of the material comprise another roll set and wherein means are provided for shifting one of said roll sets away from a predetermined position relative to said. other roll set to provide for ready entrance of the material therebetween and for returning said one roll set to said. predetermined position following entrance of the material therebetween.

3. Apparatus in accordance with claim 1 wherein each of the rolls has a peripheral surface formed of resilient rubber.

References Cited in the file of this patent UNITED STATES PATENTS 447,295 Brenner Mar. 3, 1891 1,886,581 Pitts Nov. 8, 1932 1,930,562 Krueger Oct. 17, 1933 2,323,768 Hanna July 6, 1943 2,335,196 Pecsok Nov. 23, 1943 2,632,495 Agee Mar. 24, 1953

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Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3163201A (en) * 1960-02-10 1964-12-29 Indugas Ges Fur Ind Gasverwend Process and apparatus for producing conductive sheet material having low power losses
US3457754A (en) * 1966-06-22 1969-07-29 Wirth Co Kg Masch Bohr Roller straightening machine
US3524337A (en) * 1968-04-09 1970-08-18 Scan American Ind Inc Venetian blind slat straightener
US4201074A (en) * 1976-10-18 1980-05-06 Transworld Drilling Company Submersible pipe installation systems
US4594872A (en) * 1984-10-30 1986-06-17 Nordlof Richard D Apparatus for straightening strip material
US5520039A (en) * 1993-04-06 1996-05-28 Witels Apparate-Maschinen Albert Gmbh & Co Kg Straightening apparatus for wire, cable and tubular material

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US447295A (en) * 1891-03-03 Stave-bending machine
US1886581A (en) * 1929-02-21 1932-11-08 Michigan Steel Corp Method of treating steel
US1930562A (en) * 1932-08-11 1933-10-17 Bliss E W Co Method and apparatus for forming smoothly rounded can bodies
US2323768A (en) * 1941-10-23 1943-07-06 Westinghouse Electric & Mfg Co Strip straightener
US2335196A (en) * 1940-09-09 1943-11-23 Osborn Mfg Co Metal cleaning
US2632495A (en) * 1949-11-04 1953-03-24 Floyd A Agee Apparatus for making pleated material

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US447295A (en) * 1891-03-03 Stave-bending machine
US1886581A (en) * 1929-02-21 1932-11-08 Michigan Steel Corp Method of treating steel
US1930562A (en) * 1932-08-11 1933-10-17 Bliss E W Co Method and apparatus for forming smoothly rounded can bodies
US2335196A (en) * 1940-09-09 1943-11-23 Osborn Mfg Co Metal cleaning
US2323768A (en) * 1941-10-23 1943-07-06 Westinghouse Electric & Mfg Co Strip straightener
US2632495A (en) * 1949-11-04 1953-03-24 Floyd A Agee Apparatus for making pleated material

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3163201A (en) * 1960-02-10 1964-12-29 Indugas Ges Fur Ind Gasverwend Process and apparatus for producing conductive sheet material having low power losses
US3457754A (en) * 1966-06-22 1969-07-29 Wirth Co Kg Masch Bohr Roller straightening machine
US3524337A (en) * 1968-04-09 1970-08-18 Scan American Ind Inc Venetian blind slat straightener
US4201074A (en) * 1976-10-18 1980-05-06 Transworld Drilling Company Submersible pipe installation systems
US4594872A (en) * 1984-10-30 1986-06-17 Nordlof Richard D Apparatus for straightening strip material
US5520039A (en) * 1993-04-06 1996-05-28 Witels Apparate-Maschinen Albert Gmbh & Co Kg Straightening apparatus for wire, cable and tubular material

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