Патент USA US2411801код для вставки
Nov. 26, 1946. 2,411,801 J. S. NIELSEN ETAL METAL BENDING AND STRETCHING APPARATUS ‘ Filed Sept. 1i, 1943 3 Sheets-Sheet 1 _1. 5.‘k .james 6. Nie/51221K» ~Nov. 26, 1946. l J. s. NlELsEN ETAL 2,411,801 ' METAL BENDING AND STRETCHING ÁPPARATUS Filed Sept. 11, 1943 Sheets-Sheet 2 2,411,801 Patented Nov. 26, _1946 UNirîeo STATES PATENT OFFICE METAL BENDING AND STRETCHIÑG . ` ~ » APPARATUS ,Y ' 'rames s. Nielsen, Stow, ana Clyde B. Machala, Akron, 0hio,- assìgnors to Goodyear Aircraft Akron, Ohio, a corporation of ~ Corporation, Delaware Application september 11, 1943,*seria1na‘501p16 f 13 Claims. 1 This invention Yrelates to 'metal stretching and bending apparatus, and, vin particular, to an ap paratus for forming straight bar material of metal and the like of any cross Sectional conñguration into smooth contours of predetermined shape by stretching the stock material and at the same time (Cl. 153-40)> 2 or sheet metal bars >around a revolvable‘form block without spring back. Another` object of the invention is to provide apparatus for forming metal, or like material, -» around a form block over van angle of more than about 180 degrees. Another object of the invention'is the provision Winding it around a forming die. ‘ of compact apparatus of the type described and ' Machines are known on which a tube or the like which> is relatively inexpensive to build and to is bent without stretchingaround a die. How' maintain, long wearing and easily operated in use ever, in this case a male and a female die are re with a minimum of readilytrained personnel, and quired to avoid wrinkling of the material and the which rapidly and efficiently turns out high grade rather expensive die does not give satisfactory re and uniform work. sults without- compensating the die for spring Another object of the invention is to provide back of the material. ` apparatus of the character described and operable 15 Other'machines are known which apply stretch solely with a iluid pressure motor. ` ing while bending oi the work piece takes place. Another object of the invention is the provision However, machines of this type, although produc of a modification of the apparatus wherein the ing satisfactory'work ori-some sectionsand sizes, sprocket and chain assembly need not be em are bulky and heavy in construction, require a . large space‘and considerable personnel, and are at ployed.> Another object of the invention is the provision not adapted'f or bending through an angle of more of a sectional or multi-part die for forming metal than 180 degrees, but usually operate to through substantially without spring back. angles or" much less than '1189 degrees. Other objects of the invention will appear as 4The! present invention avoids theA shortcomings è5 the description proceeds. of these >known constructions by a novel arrange ment whereby the stock material is stretched and at the same time is Wound around a form For a better understanding of the Y invention reference should be had to the accompanying drawings wherein: f block or die secured to a turntable. The stretch - Figure 1 is a topplan View of o-ne embodiment of ing means, usually a hydraulic cylinder, is vat invention showing a work piece in the ma tached to an endless‘chain which passes'around ai the chine after a, completed bending operation; a sprocket secured to the turntable at one end and Figure 2 is a front elevation of the apparatus of an idler sprocket mounted at the opposite end of Y Figure 1 with the front supports broken away for a the Work table. y As the table rotates, the cylinder better showing of the driving mechanism ofthe moves toward the turntable, at exactly the same 'i machine; . lineal' speed- as the periphery of the sprocket.' Figure 3 is a fractional section through the table ' ' Twofpneuma-tically operated jaws are employed to hold` the stock, one jaw being fastened tothe piston rod of the'cylinder and one jaw being se- p cured to the turntable adjacent theform block. The construction of the apparatus is such that a constant -or controlled -tensile force is exerted on the Ypart during the entire vforn'iing operation. Owingrto the fact that the distance fromïform' block contour to the center of theturntable may vary, the circumferential speed of «the form die usually differs' from the speedof the hydraulicA cylinder. " This' diiierenc'e'is compensated for by the movement vof the'fpiston in" its cylinder, thus> always securingthe necessary ¿tension inthe' work on line IIT-IIIfof Figure 2; K ' Figure 4 is a diagrammatic plan view'illustrat-l ing the manner in whichthe apparatus of Figures 1 to 3 can ber operated without a motor. «Figure 5 isla diagrammatic` plan View of a mf'idi-~.y neat-ion of the apparatus of> Figures 1 to'3; Figure/6` is a plan lView 0f a multi-part form ing die; ' _ Y ' Figure 7 is a'sectional view taken onerline VïI VÍI of -Figure 6; f Figure 8 is a sectional view taken on line VIEI VIII of Figure 6. ' » ' ~ The apparatus of the invention in oneL best piece.>`4 The finishedflarticle thus formed on this 50 known embodiment consists of a table, indicated as a whole bythe numeral lâ, and including sup machine has fa smooth surface vfree from wrinklesr` ports l2 to which is secured a top I4 at the ends and conforms perfectly to the shape of the form' die with practically no spring back. Y The main object ’ciA this inventionv isl the pro of 4which are mounted vertical shafts IB and I8 in bearings 20, 22 and 24,- 26, respectively. The vision of apparatusîfor formingr rolled, extruded 55 _bearings 2li and 24 are fastened to the table top 2,411,801 3 and the bearings 24 and 26 to transverse channels 23 connecting the table supports. To each one 4 and requires only a single operator. 'Í'o make , the machine ready for operation the turntable 34 of the shafts It and I3 just beneath the top of the table is keyed a sprocket 3@ which sprockets are connected by an endless chain 32. The shaft |8, which extends through and above the top of the table, carries at its upper end a- turntable or die support 34 provided with anchor Vslots 36. The is rotated to position the gripping devices ‘I6 and £28 in alignment and a distance apart about equal to the length of the work piece. The work piece then is inserted in one pair of jaws and then in the other pair of »jaws by moving the piston 'I2 back or forth, as the case may be, by shaft IS is preferably driven, usually by an elec supplying controlled amounts of ñuid thereto from tric reversible motor 38 of the variable or multi 10 the pump iv2il. With the forming die and its speed type, and operates a reduction gear box 48 supporting block rvlocked against relative move located underneath the table. _ _ In the chain 32 is inserted a special adjustable link 5E] to which is attached, by bolts 52, a slide ment, the turntable is put in motion by opera tion of the motor 38 and the work piece W is brought under suñicient tension by the controlled or cross head 54 consisting of bottom and top 15 flow of fluid to the cylinder 10 to permanently parts 5t and :18 connected by bolts 60 and slid stretch the material the desired amount. The able in a slot B2 in the table top I4. In the upper stretching of the work piece prevents wrinkling part 58 of the slide is a, fixed pivot stud 62 about of the material during the bending process. The which is rotatable a support 66. To prevent eX pivotal mounting of the power cylinder support cessive tipping stress on the stud 62 the support 20 results in the stretching force being applied to 66 is held against the upper slide part 58 by one the work piece in a direction which is always tan or more gib fingers 68. gent to the circumference of the forming die. To the support G5 is bolted in a vertically ad The tension on the work piece, and, accordingly, justable manner a hydraulic power cylinder 10 the permanent stretch thereof may be regulated which furnishes the power for stretching the work 25 during the bending operation to obtain the best material W. The cylinder lo includes a piston results and a perfectly smooth article Without 'r2 having a hollow piston rod 'i4 which carries any spring back. In many cases,l however, the at one end a gripping device ‘it having movable tensio-n or stretch applied can be kept constant jaws 86. The side of the piston opposite the during the bending process. rod 'F4 is provided with a hollow rod extension 30 In cases where the bending angle on the work îS to the end of which is attached a bracket 80 piece is obtuse or not smaller than 90 degrees supporting a small pneumatic cylinder 82 having and the bending radius not too small the die can a piston rod 534 which extends slidably through remain fixed to its support without resulting in the hollow bore of the extension 28 and rod 14 spring back. However, in c'ases where the turn to operate the jaws 86 in the gripping device 1B. 35 table is rotated through more than a right angle Another gripping device 88 is adjustably mount to bend the work piece to less than a right angle, ed o-n the turntable 34 by clamps Sii. This de and particularly when the work piece is bent vice also is provided with a small pneumatic around a small radius, itis very advantageous cylinder 92 operating jaws 86a by which the end to make the die swingable while or after the of the work piece W is held while being stretched 40 bending is performed. One manner of achieving and bent over a form die It@ mounted on the the swinging of the die is to position it so that table. the slot ||2 is on the side of the bolt opposite It will be understood that the work W is` from that shown in Figure 1. The die is then stretched between the gripping devices V'i6 >and fastened on the block suñiciently tight to permit 83 as it is bent around. the form die IDG which a some slippage so that when the turntable rotates is adjustably mounted on the turntable 34. More the friction between the work piece and the die particularly, the die ità) may take a wide variety will tend to and will turn the die. of shapes, sizes or constructions, but in the form Another, and usually a preferred way of op illustrated it is made of two pieces |32 and |04 erating the pivoted part die, is to complete or bolted together and which in assembled comple 50 substantially complete the bending of the work mentary relation form a curved groove into which piece and the rotation of the turntable before re a portion of the work piece W slidably fits. IThe moving the locking p_in. Thereafter, the locking forming die mi) is either ñxedly or swingably pin is removed and the work piece is given a ñnal mounted by two bolts |85 and |68 to a block ||il stretch accompanied by a rocking of the pivoted which in turn is fastened to the turntable 34 by 55 part of the die. The important feature in this clamps QG. The forming die when it is made operation is that the ñnal and setting stretch swingable about the bolt ißt is (as is usually the thereby imparted to the work piece is not con case when material is to be bent through an centrated at one end of the Work piece (as is arc approaching 180 degrees) provided with an the casewhere the friction between the die and arcuate slot | l2 of suitable length through which the work piece of a fixed die prevents the pull passes the bolt |86 thereby forming a stop tothe on one end of the work piece from being trans -arcuate movement of the die in either direction. mitted to the other end thereof), but is applied Provision is also made for fixing the relative equally `toboth ends of the work piece by the position of the die and its supporting block by rocking of the die. n placing the hole ||\B in the die over the hole ||8 65 In vthe operation of the ,apparatus it will be` in the block and by inserting a locking pin understood that as the work piece is bent around therein. , the die block the sprocket and chain drive moves For supplying the hydraulic cylinders with fluid the support for the hydraulic cylinder towards under pressure and to make the apparatus in the die block whereby only aA relatively short dependent of available ñuid pressure lines, a 70 hydraulic cylinderis required as distinguished pump |26 is ordinarily provided which is driven from a long awkward cylinder which might by an electric motor |22 and with the pump otherwise have been necessary. Further, hy being fed from a service tank |24 to which the draulic control of the tension and piston move ñuid, usually oil,vreturns. . ment in the cylinder is facilitated particularly The operation ofthe machine is very simple 75 where the die block is positioned on the turn 2,411,861 '5 , most conveniently employed in conjunction with~ table so as to have about the same radius as the turning sprocket. a particular die block, such as Vindicated at'lllilb,v which when positioned as 'shown on turntable 342) can be turned by the turntable to wrap the rWork ` It will be noted `that with the apparatus of the present invention work pieces can bebent into complexer compound curves and through angles of upto or even greater than 360 degrees. piece around it, all vwithout appreciably changing the ¿position of the piston in a iiXed .hydraulic The cylinder 'lâh but which is'free to turnabout a apparatusfrequires Aonly the> very simplest kind vertical pivot. or" , die block constructions. ' ' In this embodiment of the invention thetnrn Although the drawings arev shown `with only one turntable as a form die support, the'` invention 10 table- 34h 'must be rotated by positive turning and. bending means, andthe entire kapparatus may contemplates providingira 'pair` of turntables, one _tal-:e the form of a Vseparate machine having a on yeach vertical shaft and av hydraulic cylinder _ ~ somewhat longer hydraulic cylinder to take care associated with each stretch of the chain 32 ex of any discrepancies in the windup of the work piece. On the otherhand, lthe apparatus ‘of ~iï‘ig tending around the sprockets Í35.'. rlîhus„a second setof rstretching and bending devices is provided opposite the'one shown, thereby doublingthe pro ductive capacity of the machine without increas ures 1 to 3 may be modiñed to have a stationary pivot _post or hole to which the hydraulic cylinder can vbe movedÍ for operations uponcertain work ~ ' pieces and .dieblocks., ~ a « From the description it will be recognized that Figures 6, 7 and S kshow a modiiication of the the present invention is a decided` improvement die block‘oi the preceding iìgures of the draw-r over previous constructions oi stretch-bending ings. More specifically, in the embodiment of machines in that its output is of the highest qual the invention of Figures l to 3 the entire die ity and perfection in smoothness as well asin block is made movable, whereas Figures 4 and 5 shape and withspring back substantially elimi show stationary die blocks. In Figures 5, *l 8 nated. The articles made by the improved appa 25' part of the die block isrigid and Vpart is movable.> ratus and by a minimum of ordinary personnel It should be understood,=of course, that the var can be produced inexpensively, rapidly, and with ious die >blocks are interchangeable on the several little waste oi material. Besides, the space re forms of the invention shown, the use of any quired for the improved apparatus is smaller and particular block being dependent upon thepar its cost lower than that of machines for similar 30 ticular shape to be formed of the-work piece, all ing its size. . purposes. ' as already explained heretoiore.- - Turning now to Figure 4 of the drawings, there tion of the improved apparatus wherein operation ñxedly secured b-y clamps 2id a pillow' 2li?. . The is achieved: without an electric motor 38 or other means »for rotating the turntable; More particu l'arly,A it is entirely possible and permissible to employ the hydraulic cylinder l@ of the apparatus to-achieve both stretching and bending of the workpiece. This'result can be accomplished, in 40 the inodiñcation of the invention illustrated, in asmuchas» the hydraulic cylinder _iba vhas lits pis ton rod `connected to therv work ïpieceïWa, ‘as already described, with'the work piece ‘extending around a. die block idea; The pulling force on the Work piece Wd is transmitted'through the ~ pillow has a multipart die ‘block 215, 2 i8 mounted thereon, the part 216 being rigidly fastened to the pillow and the part 218 being .,pivotally mounted as shown -with'a stud bolt 22d. -Each part of :the die block. in the form shown to pro ducela curved channel is conveniently made up' of relatively thin plates mounted top and bottom of the main dieblock and with the thinv plates bein'ggrooved :to receive the side flanges of the channel workpiece being formed. ’The turntable 2li? is-r’irovi'dedl with a clamp 22e to receive the VAendy lor“ the work piece. cylinder'ldd to the chain 32a, as before described with respect to Figures 1 to 3, and thence to the sprocket 36a and the turntable 34a. ' In Figures 6 to 8, the numeral 2li) indicates generally a turntable to whichv is adjustably b-ut has been diagrammatically illustrated a modifica ’i In fthe ¿operation of:'the apparatus, and with the parts in lthefdotted'line position shown, the Y ~ ` 50 turntable is'rotated in a clockwise direction to Accordingly, the turning moment on the turn table 36a is equal kto the stretching` tension put into the work piece "multiplied vby the sprocket radius R2, minus _the stretching tension multi pliedeby the radiusk Rl from the centeror" the 55 turntable-'to the tangent ofthe die "block,A minus theìmoment duev to irictional resistance.. Inotherv move vthe die block to the 'solid line position shown.`> During the associated bending and stretching operation the movable segment ‘lla of the-die may be left free to move or it may be held against movement until »near the end of the oper ation, _all as already described in conjunction wordsi-ïas long as the radiusoithe" chain-'sprocket 3Go is somewhat greater »than ïthe‘radius oi 'the die block :leed mOunteà-i’nh‘the turntable, any with the apparatus of Figures i to 3. In any worklpiece ¿We willY also result >inïfa‘rotation ofv the- turntable toi-bend or wind the workpiece can beïmade without 'spring backffrom-Duralumin event-"by employing one or the other 'of the stretching and‘bendi'ng operations,- a wideïvariety forcer»appliedjtofthe cylinder ldd »to stretch the 60 of irregularly‘or >regularly changing radius forms'V around the form’block mila. ' ' . ï By applyingïaisuitable‘controllablebrake, indi or other> rolled, extruded, ‘or votl'lerwise lshapeizl metal members. ~ ` ` ' l Having now described the invention in’ detail in reference to the drawings' showing but icertain cated as awhole‘by the'num'eral Zell, to the rota 65 >examples ofi construction, it should clearly be tion ofthe turntable Silmïthe desiredvrelation between #the bending and the stretchingy of the understo‘o'dfthat-> the invention Àis ` not restricted' thereto> blut ’many deviations tl’ierei’ronfil may bev workpiece canbewcontrolled; ~ The brake has beeïn'conveniently' shown as applied tofthe shaft 70 'made within _thescope andspirit of the> appended i3d mounting“ one‘ofvthe'sprocketsßßar‘ " ' v .C1aimS.: Y In Figure 5l is illustrated still another embodi >` lWhat is claimed is:'V f , ' f, ~; y " Y » i.> AA combines stretching >and bending ma' elongated‘material int'ocon-l chain mechanism has been eliminated for moving~ ~ ' Vcl'iinevffo-r,shaping Íng'a rotatable bending means hav-_ tours, „oomprl l the hydraulic cylinder> towards the die >'block dur 75 ing -the "contour to lwhich thematerial is tofbeV ' ’ ing 'tl'ie-bendin‘T operation'. This modiiication is ment 'ci the invention 'wherein' theV sprocket and 7 2,411,801, 8 bent, means movable with said bending means for gripping one end of said material, means for rotating said bending means, ñuid pressure actu ated stretching means adapted to grip said mate rial at a point spaced from said bending means being swingable at least in part about a ñxed point thereon in a direction opposite to the direc tion in which the turntable rotates during a bend ing operation. 7. A combined stretching and bending machine for shaping elongated material into contours for imparting a stretch to the material as it is bent around the bending means, means mounting the stretching means for movement to and from comprising a rotatable forming die table, means for rotating the table,. an endless power chain drive associated with said table and having por the bending means, and means controlled by the rotating bending means for controlling the to and 10i tions of the chain moving parallel but in opposite from position of the stretching means. direction, and a hydraulic` stretching cylinder in 2. A combined stretching and bending ma chine for shaping bar material into contours, comprising two shafts positioned in parallel re _fixed relation longitudinally of the chain and pivotally secured thereto. 8. A combined stretching and bending ma lation a suitable distance apart, a sprocket on 15" chine for bending elongated 'members into prede each shaft, a chain actively engaging said sprockets and having two longitudinal portions moving in opposite directions, die block means carried for rotation by one of said shafts, stretch termined shapes, comprising a turntable, a bend ing die, means for mounting the die on the turn table, means adapted to anchor the front end ing means attached to said chain and being in cooperative relation to said die blo-ck means, and a reversible power unit in driving connection with one of said shafts. 3. A combined stretching and bending machine for rotating the turntable to wrap said member of one of said members on the turntable, means around the die while the rear end of said mem ber is thereby drawn forward toward the die, fluid pressure actuated means adapted to be con nected to the rear end of said member for exert for shaping bar material into contours, compris ing a shaft, endless iiexible means engaging said shaft and having two longitudinal portions mov ing in opposite directions upon rotation of the shaft, a form block mounted to rotate with said shaft, a pivoted support fastened to said flexible 304 means, stretching means including a hydrauli cally operated cylinder adjustably mounted to said pivoted support and being cooperative with said form block, and a power unit in driving con nection with said shaft. 4. A combined stretching and bending machine ing thereon suiìcient resistance to said forward movement to stretch said member beyond its elas tic limit, and means driven from said turntable rotating means for moving said fluid actuated means forward toward the die at a predetermined rate. 9. A combined stretching and bending machine for bending elongated members into predeter mined shapes, comprising a bending die, means adapted to anchor the front end of one of said members adjacent the die, an endless chain for rotating the die to wrapsaid member around it kfor shaping elongated material into contours, while the rear end of said member is thereby comprising a table, a vertical shaft passing drawn forward toward the die, and ñuid pressure through and being journaled adjacent one end of actuated means mounted on said chain and said table, bending means ñxed to said shaft, a 40 adapted to be connected to the rear end of said second vertical shaft jo-urnaled at the other end member for exerting thereon suñ‘icient resistance of said table, a sprocket mounted on each one to said forward movement to stretch said mem of said shai‘ts, an endless chain engaging -said ber beyond its elastic limit. ` sprockets, a stretching means attached tor said l0. A combined stretching and bending ma chain and cooperating with said bendingmeans, chine for bending elongated members into pre and a reversible power unit in driving connection determined shapes, comprising a bending die, with one of said shafts. means adapted to anchor the front end of one 5. A combined stretching and bending machine of said members adjacent the die, means for ro for shaping elongated material into contours, tating the die to wrap said member around it comprising a table, a vertical shaft >passing while the rear end of said member is thereby through and being journaled adjacent one end of drawn forward toward the die, a piston adapted said table, a forming die ñxed to said shaft, a to be connected to the rear end of said member, a second vertical shaft journaled at the other end hydraulic cylinder housing said piston and of said table, a sprocket mounted on each one of mounted in spaced relation to the die, and means said shafts below the table, an endless chain 55 for supplying hydraulic pressure to said cylinder engaging said sprockets, a block attached to said . in front of the piston whereby to resist forward chain and being guided in a slot cut into and movement of the piston sufiiciently to stretch said along one side of the table above said chain, a member beyond its elastic limit. fluid pressure motor connected by a vertical pivot l1. A combined stretching and bending ma to the block, and material gripping means car 60 chine for bending elongated members into prede ried in association with the die and with the termined shapes,> comprising a table, a turn fluid pressure motor, said fluid pressure motor table rotatably mounted thereon, a bending die, being adapted to stretch said material as it is means for detachab-ly mounting’the die on vthe wrapped around said forming die. turntable, means adapted to anchor the front 6. A combined stretching and bending machine 65 end of 4one of said members in any desired/posi for shaping bar stock into contours comprising a tion on »the turntable, means for rotating the turntable, means for rotating the table, a bar turntable to wrap said member around thedie stock stretching device,> means operatively con While the rear end of said member is thereby necting the stretching device to move itin the drawnI forward toward the die, a, piston adapted same direction as the turntable, a gripping device disposed on the turntable and adapted to holding one end of the bar stock, a second gripping device attached to the stretching device and serving to hold-the other end of said bar stock, and a form ing die Vpivotally mounted on said turntable and to be connected to the rear end of said member, a hydraulic cylinder housing said piston, and lmeans pivotally mounting the cylinder on said table on an axis parallel to and a ñXed distance from the'axis of the turntable, said cylinder being adapted to receive hydraulic pressure in front of 2,411,801 l > 9 the piston whereby to resist forward movement of the piston in the cylinder suiîiciently to stretch said member beyond its elastic limit. 12. In a stretching and bending machine for> shaping bar stock into contours,> a turntable, means for connecting one end of said stock to the table, means for rotating the table, a stretch ing device adapted to be connected to the oppo site end of said stock for holding and stretching it,«and a forming die mounted on said turntable for bending said stock as the table rotates and being adapted to swing during a bar stock bend ing and stretching operation about a ñxed point on the turntable in a direction opposite to the direction in which the turntable rotates. 10 13. In combination, a forming means, means for rotating the same, holding means adapted to secure a portion of a length of material to move with the forming means, means gripping an other portion of the material, meansA associated with the gripping means for applying a stretch to the material, and a chain operatively connected to the forming means and to the gripping means for moving the gripping means toward the form ing means upon rotation thereof. JAMES s. NIELSEN. CLYDE B. MITCHELLA.