US1187144A - Carton-blank-forming machine. - Google Patents

Description

E. M. HAWKINS.

CARTON BLANK FORMING MAcHlNE.

APPUCATION lLklJ IANy 15, 1912.

Patented June 13, 1916.

14 SHEETSwSHEET I.

/NI/ENTH ATTORNEY NMX WIT/1158858 E. M. HAWKINS.

cARToN BLANK FORMING MACHINE.

APPLICATION FILED IAN 15, |912.

Patented June 13, 1916.

14 SHEETS-SHEET 2.

INVENTOR E. M. HAWKINS.

CARTON BLANK FORMING MACHINE.

APPLHLAYION HLM) IAN-15,1912

lzltvniwl .llllw 13, 19W.

14 SHELTS SHEET 3.

E. M. HAWKINS. CARTON BLANK FORMxNG MACHaNt.

/wvucmmn mw 1A x5, lssz. 1 187,144. lzltvntvdJmw 1d, 1916. g x4 SHEETSHSHEEM.

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ATTORNEY E. M. HAwKlNs.

CARTON BLANK FORMING MACHINE.

APPLICATION FILED IAN. I5, 1912. 141873144, Patented J une 13, 1916. v I4 SHITS-SHEET 5.

WITNESSES:

E` M. HAWKINS CARTON BLANK FORMING MACHINE.

APPUCAYION FILED lAN.l5.1912.

Patented June 13, 1916.

I4 SHEETS-SHEET 6- "1"?" VENTOR E. M. HAWKINS. CARTON BLANK foN'NlNG MACHINE.

APPLICAYION FILED 1AN.15. 1912.

Patented June 131, 1916.

INVENTOR ATTURNEY H SHEETS-SHEET I.

E. M. HAWKINS.

CARTON BLANK FORMlNG MACHINE.

APPLxcAUoN mw JAN. l5, |912.

v 1,187,144. PatentedJune13,1916.

I4 SHEETS--SHEET 8.

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@Amun BLANK Hmmm MACHIN..

AIPUCAION Mii!) MN, 1.5, i312.

WITNESSES:

. HAWKNS.

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APPICA 'mf-,mm1 Jun@ 13, 1916.

14 SHEETSY SHEET I..

ATTORNEY E. M. HAWKINS.

CARTON BLANK FORMING MACHINE.

APPLICAUON mw 1AN.15, 1912.

Patfnted Junv 13, 19H3.

l4 SHEETSSHEEY i3.

E M. HAWKINS. CARTON BLANK FORMING MACHINE.

APPLICATION FILED IAN. l5. 1912. l

Patented June 13, 1916.

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UNITED STATES PATENT OFFICE.

EDGAR M. HAWKINS, OF ROCHESTER, NEW YORK, ASSIGNOR TO M. D; KNOWLTON COMPANY, F ROCHESTER, NEW YORK, A CORPORATION OF NEW YORK.

CARTON-BLANK-FDRMING MACHINE.

Specification of Letters Patent.

Application led January 15, 1912. Serial No. 671,176.

' To all 'whom it may concern State of New York, have invented certain new and useful Improvements in Carton- Blank-Forming Machines, of winch the following is a specification,

' tendency to either stand upright or else told My invention relates to a machine for making cartons of that type in which the carton blanks are both creased and slotted on certain predetermined lines to permit of their being bent or broken up7 into complete Cartons of desired form and size; the crease being made to determine the bending lines of the blanks and facilitate the blanks being bent up into carton form on those lines, and the slots being made to provide the end flaps or sections which are adapted to be folded upon each other to form the ends of the bent up or completed cartons.

The main object of my invention is to provide a simple and practical machine that will be operative to produce a complete carton. blank of the type referred to, that is, a blank creased, slotted and otherwise prepared to be set up into carton or box form.

Heretofore, so far as l am aware, it has been the usual custom to crease the blanks at all of the several bending or corner lines thereof with a crease of uniform size or depth. lt has been found in practice, however, that a size of crease which is sufiicient t0 permit of thc ready bending of the blanks on those lilfes where the blanks are to be bent only in one direction, as at the side and bottom corners of the carton, is not sufficient on those lines between the side sections and the end-aps or sections at the filling-end of the carton to give the most satisfactory or desired results, and for this reason, viz., with only a size or depth of crease between the side sections and end-flaps that is sutilcient at the bending lines between the adjoining side sections, the end-flaps have a inwardly upon each other and so obstruct the filling-oliening of the carton as to be a source of serious trouble and delay to the packer, this being particularly true in those cases where the carton is made of stili" ard relatively non-flexible material, which cannot be bent or turned backward to any om siderablc extent without breakin g or so sepaY rating the fiber of the same as o either se riously damage the carton or-destroy the same. Because of these objections, resulting from the lack of ilexibility of the carton material at the joint between the side and end sections, it has been a further and important object of my invention to provide an improved creasing means for the blank whereby said objections will be avoided, the creasing means employed by me for such purpose being operative to provide the.

blank on the bending lines between its side and end sections with larger or deeper creases than on the bending lines between its side sections; the forming of these larger or deeper creases operating to so separate and loosen up the fiber of the carton material as to furnish a sufiiciently flexible joint whereby the end sections or flaps may be readily folded outwardly or inwardly as may be required without liability of breaking or otherwise injuring the carton. Preferably these creases areformed by means operative to gradually enlarge the creases by successive creasing operations so as not to materially weaken the carton material on the creased lines.

A machine embodying my invention includes blank slotting and creasing devices, the creasing devices preferably comprising two main sets, one adapted foL forming a crease at the bending lines between the side walls of the carton, and the other adapted for forming a larger or deeper crease at the bending .lines between the side walls and the movable end flaps or sections for the purpose hereinbet'ore referred to. These slotting and creasing devices will also each preferably comprise two members, one a stationary member and the other a movable member, the stationary members of both the slotting and creasing devices being mounted on a` normally stationary support or frame and the movable members being all mountedl on a reciprocatory head or frame for movement in unison to aud from position for cooperation with the stationary members. In mimbimition with these slotting and creasing devices means are also provided for feeding the blanks through the machine in operative relation to said devices to be acted upon by them, the feeding movement of the blanks preferably being intermittent whereby the blanks will be rendered stationary while being acted upon by the Slotting and reir-ting devices.

Patented June 13, 1916. A

crossfsection the upper and lower members of two different sets of creasing devices and also showing their cooperation in successively acting upon an interposed blank to provide the same with an enlarged or deepened crease. Fig. 2G represents a slotted and creased carton blank as reduced by a machine of my invention. Yig. 27 is a perspective view of a carton made up of a blank as shown in Fig. 25. Figs. 28 and Q9 are detail views to be hereinafter referred to.

Before proceeding with a detailed de scription of the machine. l will first describe the formation of the carton or container blank produced by it. In the formation of these blanks, it will of course be understood. that the spacing of the slots and creases will be varied according to the size and shape of the cartons to be made. In. the present case, a blank is shown in Fig. 2G properly creased and slotted for the production of a rectangular carton as shown in Fig. 27, the said blank being formed with a series of creases (L1, a?, (1,3, and a4, at the corner or bending lines between the side wall sections or panels Il; a series of slots c1, c2, c3, and c4, at'its opposite longitudinal edges and in line with said creases to form the end wall sections or liaps al; and a series of creases el, c2, e, and c, arranged in lines substantially intersecting the said slots at their inner ends and in posi tion at the bending lines between the said side and end wall sections. These latter creases, as liereinbefore referred to, are preferably so formed as to provide a flexible joint between the side wall sections and the end fiaps permitting of the latter being folded, first downward against the oatside ofthe carton as shown inA Fig. :27, sg as to be out of the way of the packer in fillingr the carton. and then inwardly to close the carton, after the filling or packing operation has been completed. When the carton blankv is set up, its opposite ends f-f may be secured together by any suitable means as, for instance, by an adhesively applied stay-strip of suitable material. In the present case, however, the blank is shown as being formed at one end with a short extension gl, which l term the securing flap, which is adapted to be glued or riveted to the adjoining wall section as a means of securing said sections together.

To now describe the machine, the main frame thereof, which may be of any desired form or construction suitable for the purpose, is here shown as comprising a substantially rectangular horizontally-arranged casting 1 which is of skeleton form and supported in a raised position from the door by legs 2 (See Figs. l to 4 inclusive). Mounted upon, this frame are the lower members of the slotting and creasing devices to be hereinafter-described in detail. Above this main frame 1 is located the reciprocatory head or frame 3, which carries the movable members of the slotting and creasing devices, the same being here shown as similar in form and construction to the lower frame l. This upper frame 3 is supported at opposite sides and vertically reciprocated, by means of eccentric rods 4 which connect nt their upper ends with the opposite ends of tivo shafts 5, mounted in said frame 3, and at their lower ends connect with eccentrics 6 on shafts 7 and 8 journaled in the lower frame. T bese shafts T and 8 each connect through a pair of gears 9, 9, with a shaft 10, which in turn connects through a gear-wheel 11 and pinion 12 with the main driving shaft 13, which latter' is here shown as adapted to be driven from a drive pulley 14 through the medium of a clutch 15. The gears 9, 9, between the shafts 10 and the eccentric shafts 7 and S are arranged with one air at one side of the machine and the ot er pair at the opposite side of the machine in order to properly distribute the strain on the parts. These gears 9, 9, are preferably of elliptical form in order to impart to the frame 3 a variable or fast and slow movement, the' saine being set in a manner to give said frame its slowest movement during the upper part of its stroke and its fastest movement during the lower part of its stroke; the reason Jfor this being `to provide the maximum amount of time while the frame 3 is up for the passage of the blank from one position to be operated upon to another, as hereinafter referred to. Vertically arranged posts 1G, 1G, fixed to the lower frame and engaging the upper frame 3 within openings adjacent its oppostie sides, as shown in Figs. 2 and 3, act to guide said upper frame in its reciprmiating movement.

Mounted upon the frame 1 are the lower members of the slotting and creasing devices whirrh include two sets of parallel longitudina ly arranged creasing dies 17-17 and 15S-18' and a transversely arranged slotting and creasing die 19 located at about the center of the machine and intersecting said first-mentioned sets of dies at their adjacent ends, as clearly shown in Fig. The die members lT--18 at the left hand side of the machine are respectively mounted on heads Z0 and '21 which have a fixed connection with the frame 1, while the die members 1718 at the right hand side of the machine are respectively mounted Qn heads QQ and 23 which have an adjustable connection with frame 1, whereby the members l7--18 may be adjusted laterally with respect to the members 17-18 according tothe size and shape of the carton blank to be pro-i duced.

Connected to the upper reciprocatory frame 3 to be operated thereby are the mvable members of the slotting and creasing devices, which include two setsof parallel tion with the lower lonnitniilinally arranged creasing 244-24 and 2.551 for eo'operni n the oorresgmnding: lower 'lies lT-Ml :intl 'll--lf to form the ri Innes e", e2, ff', el, of the earton blank, a tranevorseiyarrangod creasing die ft2 between :saiil i' ot' dies hvll and l1-M25' for coopevation with the lower alie 1*.) nl the Central par thereof to form the creases if?. u, fri, a?, of the enrton blnnlnnntl two blotting; knives i and :it opposite emile; ot the the, 26 lor ioilieradie il at its opposite. ends to form the slots ffl, :infl f", ot the carton blank. The 'iront :unl rear alie ineinbers fel-25 at the lt-bbnnfi infie of the niaehine, in similar mann io the peratire members l'L-lfi, are nionmoil on liemls 13G nml 3l having a ijwil. eoiineeiion "li i.' u traine 3, ivbile thev iront Lind reni' ille n'iefne bers '2-f .i at thevrighhhzind siile of the nnwhiiw, also in siinilnr manner to the en operative niemberff iT lr', nre mounten on heads iii. and 33 whiff'h have :in nllj Stable Connection with the irzzaiie 2 whereby the members 2l-25 muy be, mlinsied lnterzilly with respert to the members i-H ln oi bends of the lower veriienily-si:itionai'y members l'T--l8 being' conne exil with bracket nrnis 36E :if snilii traina lijf snitnble fastening mean-1i snel-i as bolts $2? (see Fig. ll), :irnl the supporting: heads of the upper reciproentor), members QJ-V being; eonneoteil Ywith said frame by means of gibs 35% (see Fig'. in n manner to permit of the reoipi'oentory movement of the heads xelntive to said frame Kit "the lntter, thus connected with the adjustable lie sopporting' heads, is engaged by two. entlwise sta tionalv screws 40, 4U, mounted in the, frame Il.` wbieh screws are each connected by snitable nearing! lf-#422 with an operating frank L'l- :it one side oi the machine. l); turning.; this crank in the proper llirer; ian the lies at the right-hand rifle of the niaebine ning. be adjusted to re; nate the sli-arf. between the sanne nii-fl tlios at the opposite or leftw lian'l silice olE the ninoliinrm lllio upper tzniisvei'sely arranged lie or blade 2G :and the slottini knife :it the left einl thereof both txeilly eonneel'efl to the f1-nine il. "l'lio shutting kil le nt the right enil of tho (lie "ZG, however, if; ronnzeteil with the frame in :i manner to pern'iit of its being: nrljnsteil laterally with the ille inem bers {BBL-flo. This ailinstinent of the knife be provide-il for in any snitabie manner. ln the 'present case, as most clearly shown in '2l and Q3, said knife is conneriefl to the creasing die Z6 1n a manner to be moved vertieallvitherewith. and at the #inging :it one einl 'with the under sirle 0f re snpnwteffl by -prings i8 engaging bolts .il :ittnenml if the lingers, in manner to yieleingly honi the knife in operative en- ;.fizie'e mit inn tlm loire-r edge ot' the creasing: @li-:s f :intl permit of its ready adjustment lonnitnilinnlljv ol thev latter. Lugs 50 on the aflinstnhle bends 3Q and l engaging with the enfle of the bars 47, 47, on the knife serve to vonneot the latter with said heads :unl (rinse, it to be moved with them when they :ire shifted to afijnst the position of the adjustable lits relatively to the stationary (lies as hereinbefore referred to.

The groove 45' in the upper edge of the knife Z8 may be prnvileil in :my suitable manner. l n the present ease, as most clearly "i 9 it is provided by forming shown in i .55. a, the knife, of three plates riveted or otherwise seem-ed together with the upper edge of the' middle plate terminating below the upper ezlges of the two outer plates as shown.

The transversely-:irranged slotting and @easing lie 19 is shown in the present case (see Fig. 22) as comprising two parallel members 19, 19, supported by die holders 55, 55, fixedly connected to the lower frame l. These (lie members are arranged with a, space or slot therebetween to receive the creasing die or blade 26 and the slotting knives "7 and 28; the creasing die 26 being of sufficiently less width than the space between said members as to cooperate with thenl to merely Creuse the blanks, as shown in Figi, 22, and the slottingr knives being of sach width as to cooperate with said mem.- bers to ent nml slot the blank. Two cutters or cutter :lies 511' and 57 are preferably lofnnieil lwtween the rliel members 19', 19', in posit/ion Yior Cooperating 'with the inner 'ranrsverse enrls nit the slotti'ng knives 27 and in cutting: the blanks at the inner or Closed ends of the slots, these cutters together with the cooperating transverse ends of the slotting knives constituting what I term slotend entiers. The ri ttor 56 (see Fig. 10) wliieh coop rntes with the laterally stationary knife, "27 xedly supported in its position` but the mittel? :37 which cooperates With the laterally ailjustnfble knife 28 is adjustably supported in its position for adjustment with said knife. ln the present said cutter die 57 is yieldingly supported by a plate 58 through the medi um of interposed springs 59 (see F ig. 21) in order that it may coperate Withthc knife 28 upon thc descent of the latter to cutting position and thereafter be moved downwardly by the creasing sets arranged slot 63 in the plate 60 blade 26 and out of the way ofithe latter upon its passing to creasing position, as shown in Fig. 22, the arrangement of the parts being such that the slotting devices act in advance of the creasing devices. The cutter-die supporting plate 58 is 'connected With a. slotted plate 60 (see Fig. 28) which is slidably supported by the die-holders 55 (see Figs. 21 and 22) with one end engaging the cutter die 57 within a notch G1 in its nnder side and thereby supporting said die against endwise movement on '.s supporting Springs 59. The other end of said plate Sil engages a notched extension G2 of the adjustable slottin knife 28 so as to connect the cutter-die 5 with said knife whereby it will be moved with the latter upon any adjustment of the same and so be caused to maintain its operative relation thereto. The is located immediately beneath the knife, 28 mit Waste chips from the blanks to drop downwardly therethrough.

Having now described the main features of the slotting and creasing devices. I Iwill next describe the devices for controlling thc passage of the blanks through the machine t0 be acted upon by said slotting and creasing devices.

At the front end of the machine is located a suitable support or table--a section of which is indicated at (i5-upon which the blanks or sheets to be operated upon are laced. From this table the operator feeds the. sheets to the machine, through which they are fed or carried by suitable feeding devices. Then being so fed through the machine the sheets are guided by suitable gages in order to be properly positioned relatively to the slotting and. creasing ilevices when acted upon by them. These gages in the present case are formed in two at opposite sides of the niachine. The set at the left side of the machine, indicated at 66, 67, 68. and Gf) (sce Fig. 3), aref supported in laterally adjnstable position on stationary table sections by suitable clamping devices, such as the hand-screws 7l, whereby they may be set for any desired length of slot to be cut by the knife 9.7. The set of gages at` the right side of the machine, indicated at and 7B.

are supportcdhin a laterally adjustable position on the die supporting heads 2Q and 23 by means to be pescndy described. whereby they may be adjusted relata-rely to ,he opposing gagcs ac"ording to the width of the and is adapted to per-` sheets to bc ted therebetween. These gages 72 and 7 3 are preferably set a sufficient distance from the opposing gages to permit ot" the sheets being freely entered between them and are automatically operated upon the entry ot' a sheet between them to advance into engagement with the adjacent edge of the sheet and move the sheet firmly against the oppositely located stationary gages and so cause it to be accurately positioned and guided during its passage through the machine. The means here shown for so tuviorating the gages 72 and 73 comprise two sets of separate but identical devices, one set-for e'ach gage. I will therefore describe the set employed in connection with the gage 72, the description of which will be applicable to both mts.

Referring now to Figs. 3 and 11, the gage 72. slidably mounted on the head 22, is provided with a laterally extending arm 74 adiustably connected with ay sleeve 75 by a clamping collar 7 (l, `which said sleeve is slidably supported in a second sleeve 77, which in turn slidably supported in a bracket 78 rigidly attached to the head 2Q at one end thereof as shown. A spring 79 located on the slecvc 77 with its ends bearing against the bracket 78 and a collar 80 on said sleeve arts to yieldingly hold the latter in Stationary position with a second collar 81 thereon in contact with the bracket 78. A second springr located on the sleeve 75 with its ends bearing against the collar 76 thereon and the end of the sleeve 77, operates to effeet a yielding connection of said sleeve 75 and attached gage 72 with the sleeve 77 by holding a collar 84 on the outer end of the sleeve 75 in contact with the adjacent end of the sleeve 77 or the collar 80 thereon. A lever 85, pivoted at 86 to the bracket 7 8 with its lower end pivotally connected to the collar 8l., is operated by the engagement therewith of a cam 87 on the reciprocatory head 3i? to move the sleeve 77 inwardly or toward the center of the machine and so advance the connected gage 72 into engagement with a sheet to move the same against the opposing in the manner hereinbefore referred to, the spring 83 serving as a cushion to permit yielding of the gage relatively tothe positively moved sleeve 77 in the event of the gage being arrested by contact with the sheet or otherwise before completion of its full stroke. This advance movement of the gage 72 caused h v the engagement of the cam Si with the lever 85 upon the passing of the head 32. is timed to take place prior to the knife 28 reaching slotting position in order 'that the sheet will be properly positioned by en vement with theA opposing gages when the s otting and creasing operations occur. At substantially the completion of the down stroke of the head 32 the cam 8T passes below the cooperating end 85 of the lever 55;.; e'lzeri" :iles to autouuitxcsl.

t. parte i' 't Y;

'u the spriui return the i; their connecten shown in turn up stro g that the fum should mss t; without oi'ieruting the suine. und this the rfi is pivoter?. to the hc: 'i :a spring #55u miinezf' to return the rum to normul operative posi tion following itV movement :ibove salio lever, :is shown in Fifi. l1. The adjustable counwgtiou z erin -lwith the .sleeve 'ibrifire .ri-.terreni tin peru'iits of thc ruige being; mij@ iciutirly to the opposing gages :immuun: to the finiti of sheet to be operatie-l un.. ilu sleeve .Si being split adjacent its cuil to permit oi' its being firmly lumped lo the ,gage iiiin .by the (clamping collier 70.

lVlirn the sheets ure teil to the nuichiue by the operutiiu' for pai gi:- therethrough betweenllicsicleguges uuscrilml, they' ure engaged by u puir of feed rolls, il() unil 01, mounted ou :t shaft l2 which jouruuled in the heads 20 und, 2:1 ci the lower freine l and operated from lever 85 to permit i :is showin ng therev." ,li operating u pulley 5M ou theI main .living shalt 123 through a beh; f1.3 which runs over guido rolls {if} und il?. These feed rolls :ire preferably 'iornml or" rubber and provided nih' leltdnuul rev; threads (see Fig. 3) to uid in deflect ,5 the sheets toward the stationery gages :it the left isi/.ie of the machinej for the purpose hereinhe fore referred to. The roll im at, im; [p1/5 um@ of the niuihine .supported if: un eiuiwise Stationary position on the shult 0:; im'. the roll 91 at the right sidi" of the muchine is suppoited ou @nifl simili irfr enfimse s-,uiju t ment with the :,uliusiuiiie heed to 'whit-h it is loosely heid by u kcclsfcr :'fii. .X lois' mi key-way connection nur alumni Emu-wu the roll 91 und simil. le.' endwise adjustment oi' ihr The sheets are fed by th 'feed relis; 0:) und 91 into the machine between the ugfr uml lower nieu'ilers of the sluiting unil cr f devices until their mirino@ wir" position beyond or ut the rear o, versely arranged (lies, where they ure rngaged by further feeding menus by whuh they are fed on through the n'uiffhinc. These last-mentioned feeding means as here shown (see Figs.

l, 1, 3 und 12") comprise two pairs of endless feed belts urrungml mijner-nt the opposite sides of the machine for engfig ing the sheets near their opposite edges. The cooperating upper und lower belts of each pair, indicated :it 100 :and 101 respon tively, are mounted :it their front ends or those ends nearest the center of the machine, on pulleys 102 and 103 sui' v supported by the frame 1, and are mounted :it their op posite or rear ends on driving pulleys 104 Liemers and 10u attached to shafts 100 and 107 respectivelv, which shafts are journaled in un' auxiliary frame 119 at the rear of the 11min fiume und connected by gearing 108 to be driven i n unison by u driving belt u(not shown) ronnvcted with cone pulleylOS) nu the lower shaft 107. The pulleys carrying the pair of belts at tinA left side of the machine are laterally nolrndjustable, but the pulleysv carrying the pair of belts at the right side of the machine are laterally adjustable in order that the proper relation .said brits to the other puits at that side of the niuffhine muy be maintained upon` any adjustment of them. This adjustment of the belts :it the right or adjustable side of the machin-e provided for by mounting their driving pulleys 10i. und 105 for end wise uilhustment on their respective shafts, und by mounting the pulleys 102 and 103 at their front ends on the laterally adjustble head 23, the lower pulley 103 being mounted on u suitable bearing connected directly with said head and the upper pulleyv 10'. being mounted on a bearingstud 110 attached to the U-slmpe l frame 35 which is also coniwcted to said head 23. The upper pulley 102 at the left side of the machine is mounted on u bearing stud 111 car rieti by u bracket 112 uttached directly to the immo 1 (see Fig. 3). nich of the drivjug belts .iuo und 101 is engaged by a suitable belt tiglitenor, which is here shown (see l1`igs. 1' und 12) as comprising a beltengsiging pulley 111 carried by a pivoted arm 115 lmving a pivotally connected screw threaded adjusting rod 11b' adjustably conmated by nuts 117, 117, with a block 118,

mounted on cross-rod of the auxiliary treme 1.10. shown, By adiusting the po- @tion of the pulley 114 nl" the rod 1.16 sud its engaging nuts 117, the tension of the belts may be readily and iu'cumrely adjusted. In order to maintain the adjacent runs of the belts in close relation to @zich other, whereby liability of slippage of the sheets between them will be iinimized :is much it possible, the upper shaft 106 carrying the driving' pulleys at the rear ends of the belts is supported at its opposite ends in the journal boxes 120 (see Figs. 12A and 12) which are pivoted at one end on pivots 121 and at their opposite ends :ire cngaged'by springs 122 which uct to herir downwardly upon the boxes and hold the upper pulleys in yielding Contact with the lower ones. With this construction, the upper belts adjacent their rear ends will adapt themselves vertically under the action of the springs 122 to sheets of different thickness. The movement of the driving belts over the table 123 supported on the connecting beams 124 between the main and through the' medium auxiliary frames, is facilitated by provid-

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