CA1096296A - Sheet metal cutting tool - Google Patents

Abstract

ABSTRACT OF THE DISCLOSURE

Pattern cutting of sheet metal is effected auto-matically. Conveyors move a metal sheet into a pattern cutting position, the sheet being guided exactly into position. The sheet is clamped securely in pattern cut-ting position and a cutting tool begins cutting the pattern from the sheet. The cutting tool is movable in x,y, and a directions so that any type of pattern may be cut thereby.
The tool may comprise a scissors-like shearer, one blade being provided above the horizontal sheet being cut, and another blade being disposed below the sheet. Supporting tips are mounted on the conveyor to support the metal sheet in cutting position while preventing damage to the conveyor during cutting. A notcher is also provided movable along each side edge of the metal sheet the notcher motors are all controlled by a computer. After pattern cutting, the con-veyor is started up and the cut sheet transported away from the pattern cutting position, the portions cut from the sheet being supported while the waste portions of the sheet fall into a waste bin or the like.

Description

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RELATED APPLICATION
This is a division of application Serial No. 273,827 filed Mar.10, 1977.
BACKG~OUND AND SU~MARY OF TIIE INVENTION
The invention relates to a method and apparatus for automatically cutting sheet metal into patterns for forming ductwork, etc. Conventionally, such pattern cutting of sheet metal is done by hand, and is very labor intensive, relatively slow, and requires a large numbex of skilled laborers to achieve acceptable large volume production. While systems are known for cutting sheet material in general into patterns, such systems really have not been adapted so that they could functi.on in cutting sheet metal of a wide variety of gauges and widths as is necessary when pattern cutting sheet metal for making ductwork, etc.
A number of prior art devices made by Gerber Garment Technology, Inc., such as shown in U.S. patent Nos.
3,477,322, 3,370,634, 3,776,074, 3,790,154, and 3,841,187, among others, are successful in cutting patterns in sheet material such as cloth, paper, and the like, however, the cutting means employed by such devices do not, it is believed, provide for easy adaptation to cutting of sheet metal, and large production thereby is usually based on cutting a large stack of sheets all at the same time - not practical with ~5 sheet metal -- rather than by automatic conveyance of the sheet material into a cutting position.
According to the present invention, automatic pattern cutting of sheet material is practical; something ~hnt heretofore has not been practical, According to the present inven-tion a metal shee~ is automatically conveyed by conveying means into a pattern cutting position, guidance ~hereof being provideda and the metal sheet is then auto-matically clamped into place at the pattern cut~ing posi-~ion. A cutting means, which preferably comprises a shear cutter, one blade thereof being adapted to be disposed above . the horiæontally disposed-metal sheet, and the other blade thereof being adapted to be disposed belo,J the horizon-tally disposed metal sheet, Supporting means associa~ed ~r~th the conveying means support the metal sheet ~n proper position to allow positloning of the lower blade below the metal sheet for cooperation with the upper blade, and such supporting means prevent damage to the conveying means during the pattern cutting operatlon. The pattern cut-ting is controlled by a computer which activates means for moving thè cuttin~ means to any x-y coordinate of the horizontal metal sheet~ and activates a motor for moving the cutting blades to any angu-lnr, ~ position, .20 The cuttlng means cuts into the metal sheet thxough a free edge thereof, and cuts any des~red pattern, A ball bearing can be provided associated with the lo~ler blRde member to allow more exact con~rol o~ the angular position of the cutting means (especi~lly when right angles k~ . . .
or tight curves must be cut), A~ter cutting of the desired pattern from ~he metal sheet~ the clamping means are auto-mat~cally released~ the conveyi.ng means started9 und the r ~ 96,;2~

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~heet moved away from the pattern cutting position. The ~heet may be passed over a roller and the pattern held on the roller ~hile the waste cuttings fall into a waste bln disposed belo~l the roller, Notching of the metal sheet being pattern cut can also be effected automatically, notches often being necessary a't predetermined locations along the edge~ of a pattern to allow for folding of the sheet to form ductwork~
etc. Notching is effected by a notching assembly movable ~long each side edge of the metal sheet, the notching assem-blies receiving the sheet between top ~nd bottom plates thereof. The notching assemblies, are controlled by the com-p~ter also, as is an indexer for each for bringing a selected - one of a plurality of notching dies lnto operative relation-ship wlth the notching punch. The notching assemblies are movable ~ith respect to each other in the direction perpen-dicular to the feed dlrection of the metal sheets to accommo-d~tè sheets of different ~Jidths, and shims may be provided there~ith to accommodate sheets bf different gauge~
I~ ls the primary object of the present invention ~o provide a method and apparatus for effecting the auto-matic pattern cutting of sheet metal. Thls and'other ob~
Jects of the invention will become clear from an inspection of ~he deta~led descriptlon of the invention, and from the ~5 appended claims.

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r BRIE~ D~SCRIPTIOI~ OF THE DRAWI~GS
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FIGU~E 1 is a perspective vle~r of exemplary apparatus for aut~matic pattern cutting o~ sheet metal according to the present invention;
FIGURES 2a-2c are perspective, side, and top views,respecti.vely, of an exemplary cuttlng means util~z- -nble according to the present invention, and FIGURE 2d ls ~ side view of a modified ~orm of cutting means that could be employed in the apparatus of FIGURE l;
FIGU~E 3 is a detail view of clamplng means util-izable in the apparatus o~ F~GURE 1 for holding a metal ~heet to be cut ln pattern cutting position;
FIG~E 4 i5 ~ detàil perspective view.of exemplary conveying means utilizable in the apparatus of FIGURE 1~
FIGURE 5 is a detalI perspective view of an exem-plary notching assembly according to the present ~nvention9 w~th guide means ~ooperatlng therewith;
FIG~E 6 is a schematic d~agram o~ the interrela~
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t~onship between control.led and controlling components ac-cording to the present invention; and FIG~RE 7 is a top dlagrammatlc ~iew of an exem-plary metal sheet a~ter pattern cu~tin~ thereof according to the present lnvent~on , Z9~

DET~ILED DESCRIPTION OF THE I~E~TION

~ n exemplary automatic sheet metal cutter accord-ing to the present lnvention is shown in FIG 1. T he appa~
ratus according to the present invention ~ncludes the ma~or components o~ a conveying means 10 for conveying a sheet~or metal to be pattern cut into a pattexn cutting position (see FIG 7), the conveying means 10 having supporting means 12 associated there~Jith for supporting th2 sheet of metal thereon in a manner to prevent damage to the conveying means during pattern cutting of the sheet of metal, a scissors cutting tool means 14 for shear~ng the sheet of metal to pattern cut it, means 16, 18 for supporting the cuttlng . tool means 14 above ~he sheet of metal to be pattern cut ~o ~hat the cutting tool means 14 is in operative cutting po3ition with the sheet of metai, and so that ~he cu~ting tool means 14 may be moved in x and y horizontal directions ~ubstantially perpendlcular to each other, means 20 for sup-porting the.cutting tool means for substantial 360 angular .
- ~ - movemen~ about a vertical axis z, an x motor 22~ a y motor 24~ and a ~ motor 26 for ~utomatically moving the cut-. t~ng tool means 14 in the x, y, and ~ direc~ionsg respectlvely, computer control means 28 (see FIG 6) ~or autornatically con-~rolling the operation of the x, y, and ~ motor3 22, 24, and ` ?6~ respectively, for mo~ing the cuttin~ ~ool means 14 to cut a deslred preprograrnrned pattern from the metal sheet~

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r guide means 30 for gulding the movement of the sheet into pattern cutting position, and clamping means shown gen~
erally at 32 and 34, for hold~ng the sheet of'metal s-ta-tionary at ~ts pattern cutting position during pattern cutting 'thereof. Each of the indivldual co~ponents of the sheet met:-~l cutter may take a number o~ forms to accomplish pnttern cutting of the sheet metal, the follo~Ying specific embodiments thereof merely being preferred.
The cutting tool means 14 is sho~ln 1n more detail 1~ in FIGURES 2a-2c'. The actual cutting portion o~ the means 14 ~ncludes a pair of blade' members'36~ 37 for shearing of ~he metal sheet received therebet~een, one blade member 36 being disposed above a horizontally arranged plece o~ sheet metal to be cut and shearing the metal by penetrating through the ~op surface thereof, and the other blade member 37 being dlsposed below the horizontally arranged piece of sheet ~metal and shearin~ the metal by penetratina through the bo~tom su~face thereof. The e~act structure o~ the cutting poxtions may be varied -- for instance only one of the blade members 36, 37 may be moved during cutting, or both may be moved durin~ cutting -~ however one exemplary cutter that may be adapted'for use ln the present invention is sold under the name Unishear, and is manufactured by Black and Decker. A motor 38 po~rers the movement of the blade 36 ~ , . . .
J~ 25 durin~ cuttin~, Qnd in the embodiment shown in the drawlngs 'I ~ .

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' ~oves upper bla~e member 36 do~ln~ardly tlhile blade 37 re-mains stationar~. An arm 39 mounts blade member 37, the arm 39 having a leading portion 39' thereo~, and a gener-ally flat upper surface for engaglng the bottom of the sheet.
~ ~tationary guide member 41,which allows reciprocation of blade 36 therein and mounts arm 3g, has a V-notch formed in khe front end thereof, being 90 shaped to faciliate move-ment of the sheet metal to be cut into position between the ~ blades 36, 37. The member 41,has only a th~n vertical por-i0 tion 42 connecting the enlarged upper and lower portions thereo~ ~hich are adapted to be disposed above and belot~
the shee~ of metaI to be cut~ the portion 42 bein~ adapted ~o pass through the cut made in the metal sheet by the cutting blades 36~ 37. According to a~ 1mportant aspect' o~ the pres~
, ent inven~ion, a ball bearing 43 (which may be spring mounted.3 ; is provided on arm 39 adJacent the trailing edge of blade 37 . ~or engagin~ ~he bottom surface o~ the sheet of metal to be pattern,cut to facilitate powered movement o* the cu~ting portion through the sheet metal.- This is especlally import-alt wherein'sharp turns are necessary during pattern cutting~
especially s~n~e the cutting operation is automatie, The ball bearing'provides a point of engagement on the metal ~heet to àllo~.for sharp rotation o~ the cutti,ng tool means ,, ,`11~ about the vertical ~xis z, It is noted that the ball ~5 . bearin~ arrangement may be provided on any cutter9 a hand .

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automatic cutt~r~ or an automatic cutter such as according to the present invention. It is also noted that the arm 39 could be made as a lever, pivotal about a horizontal axis through a pivo-t polnt 40, and the motor 38 could both recip-rocate blade 36 and pivot lever 39~ resulting in a simultaneousmovement of the blades toward each okher during cutting. The ~all bearing 43, in such a case, would be disposed adjacent ~ivot 40 on the opposite side thereof as blade 37.
~he motor 38 of the cutting tool means 14 is mounted ~ithin a hous:lng 44 on a shaft 45, a bearing 46 belng provided o~ the top of the motor 38 for receiving shaft 453 and a bear~
`lng 47 being pro~ided on the bottom of the motor 38 for receiv-ing sh~ft 45, the sha~t 1~5 being d~rectly connec~ed to station-ary member 41 mounting the blade members 36~ 37~ The housing 44 is stationarily mounted on a oross-member 48 which is part of moun~in~ means 20g as by keys 48'9 which cross-member 48 also mounts the ~ motor 26 ~or rotating the cu~ting tool means in the~ direction. Although any suitable arrangement may be utilized, it is desired that the stepping ~ motor 26 turn a worm 49 through a gear box 503 ~ich worm 49 in turn rotates gear 51 attached to the top of shaf~ 45~ the gear 51 and shaft 45 being rotatable about the z axis, Signals to ~ motor 26 during the pattern cutting operation ~ill cause rotation of the shaft 45 tb posltion the cutting blades 36~ 37 in the correct position for cuttlng o~ the desired preprogrammed pattern.
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~g6~36 While the scissors-type cutting tool described abo~e with reference to FIGS. 2a-2c is pre~erred, for cer-t~in heavier gnuge sheet steel, it may be necessary to use a nibbler-type cutting tool ~o effectively cut patterns in the sheet metal, Such a nibbler type cutting tool may have a head like that sho~ln in FIG. 2d at 52. The head 52 in-cludes a punch~ng portion 52' that reciprocates up and down, punching a small hole with:each reciprocation, A slotted plate 54 ls provided on the he~d 52 below a sheet of metal to be cut to insure proper punching of a plug of metal wh~le the 6urrounding meta~ is not disturbed. The nibbler head 52 may be interchangeable wlth the scissors-type cutting head shown in'FIGS. 2a-2c, a rele~sable connection being provided at 5'33 or`the whole motor and cutting head arrangement may be re-placed'when it is desired to change from nibbler to scissorscutt`er and vice versa. In such'a case~ the nibbler motor will ; àlso ha~e keys 48' associated there~ith, and it may merely be 811pped into operative engagement with cross-member 48 after the scissors-type cutter is rembved. Other type cut~ing heads ~0 co~lld also be'employed, depending upon the type of material to be cut.
The cutting means 14 is mounted by mounting means 16 and 18 for movement ~o any particular cooxdinate of the area covered thereby, The mounting means 16 includes a pair ~ 25 o~ end members 55 def~ning the outer extremities of movement ) ~n the x-direct~on, the member5 55 being connected by one or more ~u~de rods 56 and a screw rod 57 or the likeO A threaded member 58 Or mountille means ~0 recelvcs the scre~-rod 57 there~n and transforms the rotation~l movement of the scre~J-rod ..

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57 to linear movement of the mountin~ means 20 for cuttlng tool 14, which linear movement is guided by the smoo~h gui.de rod(s) 55 x ste~p~ng motor 22 ls mounted on one o~
the end members 55~ and rotates the screw-rod 57 in response to controls from computer 2~.
The mounting means 18 includes a pair of frame members 60 disposed on elther end of each end member 55 of the moun~ng means 16~ each pàir of frame members 60 having one or more guide rods 61 disposed therebetween as well as a scre~l-rod 6Z disposed-between one pair (or both pairs) of frame members 60. ~he end members 55 of the n~ounting means 16-receive the guide rod(s) 61 therein~ and one o~ the members 55 has a threadecl portion receiving the.
screw-rod 62 to transform rota-t.ion~l movement of the screw-rod 62 into transl~tional movement of the members 55 in ~he y direction The y stepping motor 24 is mounted on one end of the frame members 60 for rotating scre~1-rod 62, and rotates 62 in re3ponse to signRls fed to ~t by computer 28.
lt is noted that each of the pairs of the frame members 60 must be spaced f~r enough apart (in the x-direc~io~) so that the scissors blades 36~ 37 of the cutting tool can in-i~ially engage a side edge.of thè metal sheet to be cut in order ~o begin cutting thereof Alternatively, the bottQms . - o~ the frame members 60 co~ld be loca~ed rel~tively close to the proposed edges o~ the largest sheet of metal to be re-ce~ved by the whole asse~bly, and the top portions of the ~ - frames 60 could then be flared out a l~rge enough distance ) ~ to allow movement of the cutter tool 14 into proper starting pos~t~on.
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~ lhile the mounting means have been described w~h reference to scre~-rods for providing movemen~ o~
the members 55 and 20 thereof, of course other means could be prov~ded, such ~s a rack and pinion arrangement or the like The clamping means 32, 34 ~lhich hold the sheet o~ metal to be cut stationary in a pattern cutting position, may also take a wide variety of forms; ho~lever a preferred form of the clamping means 32 is sho~rn in FIG 30 The clamp-ing means 32 includes an abutment member 64 for stopping for-ward moYement o~ the shee~ metalj which member 64 has a micro-itch 65 or the like mounted there~rith. A piston member 66 ~s movable up~Tardly in response to sensing of the sheet metal position by the switch 65, and clamps the sheet metal against the upper surface 67 o~ member 64c Shims could be provided ` for surface 67 to adapt it to a wide range o~ gauges of metal ~o be pattern cut. T~le cylinder 68 for moving the piston 66 ~n response to a signal from switch 65 may be any suitable ~ype~ such as pneumatic, hydraullc~ electrical, or the likeO
The whole assemb~y associated with member 64 is mounted on a tube 69 for pivotal movement about shaft 70 which i5 re-ce~ved by tube 69~ Gussets 71 may be provided for connecting ~he member 64 to tube 69 to minimize the strain on the member 64 from cl~mpln~ engaGement of sheet metal A po~ler means, such as cyll~der 72~ is provided attached to ~ube 69, such ~s .

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by lever 73 and clevis pin 74, to provide for pivotal move-ment of the member 64 ~lith respect to the sheet metal to move the clamping means 32 out of.khe path of travel of the sheet metal after pattern cut~ing thereof has been co~pleted and clamping thereof has been released. The cylinder 72 is also preferably controlled by the computer 28~ and the com-puter 28 also preferabl~ provides a dual control (with micro-switch 65) for the cylinder 68, the computer 28 initia~ing pivoting move~lent of the means 32 and releasing of the clamp 66,G7 after.pattern cutting of a sheet is completed.
It is also des~red that an arrangement 34 be provided on the opposite.end of the metal sheet to be cut from the olamp-ing means 32 to assist in holding the sheet in position during cutting thereo~. Such means 34 pre~erably takes the ~orm of one or more motorized squarin~ pins 75 or the like (see FIGS, 1 ~nd 4). Pin 75 is preferably pivotally mounted at 76.on a ~upport 77, pivotal motion thereof in the direction of feèd o~ the metal sheet against a spring bias being provided to allow movement thereo~ out o~ the ~ay of the metal sheet;
. however after movement of the sheet therepast3the pin 75 re-turns to its ~ertical position, and is prevented by stop 78 from pivotin~ in the opposite direction of sheet feed. Sup-port 77 is internalIy threaded and receives screw-rod 79 ~ . ~herein, and is also connected to guide rod 80~ rot~tion of ) ~ 25 ~cxew~rod 79 by motor,81.being transformed in~o transverse movement Or pin 75 by support 77. After movement o~ the .

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sheet metal there~ast, ~hen the pin 75 is re~urned to its Yertical position, the motor 81 is activated (i e ~ automati-cally~ controlled by computer 28) and i.t moves the pln 75 into abutment tlith the back edge of the metal sheet3 stop 7 preventing pivotai~ovement of pin 75 in response to such nbuttin~ engagement. The pin 75 thus assists the clamping means 32.in holding the sheet material ~n a stationary pat t~rn cutting position during pattern cutting thereof Conveying means 10 preferably comprises a number of individual co.nveyor belts 84 spaced from each other in tne ~direction9 although one large conveyor belt could ~e pro-vided (if the guide means 30 adjustment ~lere properly arranged).
Each conveyor belt 84 extends subst~ntially the length of the y distance bet;~een the frame members 60, and is powered by a powered roll ~5 rotated by a motor ~6 or the like. At least one other roll 87 besi.des powered rol~ 85 is pro~ided,.mounted - at the opposite end of the conveyor belt 84 from roll 85g both .rolls 85, 87 being rotatable about a horizontal x-axis.
~r~me ~3 ~s pr3vided~ A belt tension adjustment means 8~ may be prov~ded to insure po~lered movement of the.conveyor belt during all types of load condi.tions. Also, it is pxeferred $hat the indi.vidual con~eyor belts 84 be movable in the x-direction ~lith respect to each other to accommodate..metal ~~ sheets of varyin~ t,lidths F.or instance, if two conveyor ) ~ 25 . belts 8~ are provided~ they may be mounted for movement to .
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engage portions on either side of the metal sheet to be transported thereby~ the amount of gap provided between conveyors 8~ belng determined by the size o~ the metal ~heet. Should such a gap become too large~ of course a third,conveyor belt 84 could be provided~ Means ~or moving ~he conveyor belts 84 with respect t-o each other in the x-direction may take a wide variet~ of formsa such as that sho~n in FIG, 4 generally at 89 for moving one bel~ 8~
wh~le the other belt (cut a~ray in FIG.4) remains'stationary in the x-direction, The means 89 includes a wheel carriage 90 movable in track 98 for mounting each of the supports 91 92 for the rolls 859 87, the wheel carriage 90 having a middle portion 93 thereof that ~s threaded to recelve a screw-rod 94 thereinO The screir-rod 94 may be rota~ed by any suitable means, such as gear 95 powered by chain 96 and han~-wheel 97~ the portion 93 transforming rotational move-ment o~ the rod 94 into transversP movement of the carriage 90 in the x-direction. Of course a ~lide ~ariety of other means could be employed, such as a rack and pinion and motor-~0 ized chain--rheel. It is noted that the clamping means 34 is disposed adjacent the stationary belt 84, at the end of traYel of the movable belt 84~ so t,hat it does not interfere with the movement of the belts~, nor they ~rith it. Of course, .~ , , both belts 84 could be made movable, ~rith a common scre~,r-rod -~25 94 being provided for powering each cf them ~rom a middle ~ 15 -336~ .

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pOGition to end positions, and the means 34 would be dis-posed bet~Yeen the belts 84 at the middle stationary pos~tion ~hereof, Control of motor 86 may be effected manually, by microswitch 65, and by computer 28, The supporting means 12 associated with the con~
~eying means 10 provide support of sheet metal mounted thereon in a manner to pre~rent damage to ~he conveying means 10 dur-ing patkern cutting of a metal shee~ by the cutt~n~ tool 14, ~he supportlng means 12 pre~erably take the form of a plur-ality of tlps 100 removably mounted on conveyor belts 84 oYer the whole length thereo~, and spaced close enough ~o-gether to provlde for secure support o~ a me~al sheet on the tops 103 thereof, Each ~ip 100 is formed of hard rubber or other sturdy bu~ flexi~le material~ and may be co~nected to the conveyGr 84 by screws 101 and the like, rece~ved by in-terior threaded portions 102 of the tlp 100, The tips 100 are high enough to allow passage o~ ~he lower blade member 37 and associated structure of the cutting ~ool 14 bet~een the metal sheet and the top of belt 84 so that no damage results to belt 84 dur~ng cuttin~, Since the tips are elongated and generally in the shape of a truncated cone, ~nd are made of flexible material~ they will flex out o~
~he ~ay when enga~ed b~ the leading edge of lever 39 and/or the leading edge o~ member 41 (or t;ne plate 54) as the cut ting tool 14 is moYed around, ~Jhereb~ darnage to them ~ill also be prevented. If ~ome damage does occur to some tips 1003 however~ the dama~ed tlps may be peri~ ically replaced, .
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The gulde means 30 for guidlng the movement o~
the sheet metal into pattern cutting position preferably include a plurality of gu~de rollers 105 mounted along either side of a metal shee~ to be cut, and in abutting, S receivlng engagement therewith, While the rollers 105 ~ay take a ~ide variety of ~orms3 it is preferred that they be in the ~orm of a ball 106 or truncated wheel 107a spring biased into engagement with a side edge of metal sheet by a spring 108 or the like~ Guided linear movement of the ball 106 or truncated wheel 107 in housing 109 therefor is provided by any suitable guide means 3 such as pins 110. Each gui~e roller 105 has a ~roove lll formed therein, the groove 111 being wid,e enough to receive the lar~est gauge sheet metal to be cut therein. Shims may be provided ~or the 1~ grooYes ~11 if desired. In addition to providing guidance ~or the movement of the metal sheet into pattern cutting pos~tion3 the means 30 also serve to hoId the sheet in place during cutting -- acting in con~unction with conveyor tips 100, and clamps 32 and 34 in this regard, The guide rollers 105 on one side of a metal sheet to be cut are mounted on a support assembly 112 that is mo~~
a~le in the x-direct~on to accommodate metal sheets of differ-en~ wld~hs. A preferred means for movably mounting the a~sembly 112 is shown in FIG~ 1 generally at 113, this means ~25 113 belng similar to the means 89 for moving the conveyor ~ .

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1~9;2~L-D6 bel~s 84 wtth respect to each other. The means 113 in-~ cludes a pair Or end collars 114 for mounting as6em~1y 1129 each collar 114 receiving a guide rod 115 and a scre~l-rod 116, a threaded interior portion being provided ~or the port5on of collar 114 receiving rod 116 to transform ro-~ational mcvement of rod 116 into trans1ation~1 movement ~n the x-dlrection. The scre~-rods 116 may be driven by any ~u~table means such as gears 117 mounted on the exterior extremities thereof, rotated by a chain 118 driven by hand~heel 119.
Xn additlon to moun~ing the guide rollers 105, each ~upport assembly 112 also suppurts a notcher assembl~ 125 wh~ch is reciprocal with respect thereto (and ~ith respect to ~ metal sheet ~n pattern cutting po5ition) ~n the y-direction.
The notcher assemblies 125 are ~or making notches in the side edges of the metal sheet to facilitate bend~ng of the pattern cut therefrom along lines between the notches E~ch notcher : 125 compr~ses ~our maln components, a guide 126 ~or receiving the sheet e~ge to be notched therein, a punch 127 -which may be ei~her pneumatically or hydraulically operated -- which ` ~upplies the punching ~orce ~or notchin~, a plurality o~
tlotching dies 128$ one of which at a time is contacted by ~he punch 127 to move through the top plate of the guide 126 Rnd ~orm a notch in the met~l sheet edge, and an inde~er 129 for selecting ~hich die 128 will be used to fo~m a given notch~
Although the punch 1~7 could be made movable to position ~tself ~ "~

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oYer any one of ~he dies 128, it is preferred that the punch 127 remain stationary ~h~le the dies 128 are moved by the indexer 129 into operative posltlon with the punch 127. In-dexin~ o~ the dies 128 may be provided by a wide variety of indexers-3 such as a linear one for movin~ dles 12~ mounted in a linearly movable plateg however the geneva wheel 130 is pre.~erred~ the dies 128 being mounted around the periphery of wheel 130, and indexer 129 moving one position each time to rotate a selected die 128 into proper position beneath punch 127. The guide 126 may have a removable shim(s) 131 associate~ therewith to adapt to metal sheets o~ différent gauge to insure that the sheet is held in place properly dur~
~ng notching. A tank of compressed air 132 or the like, con-nected to punch 127 by a reelable hose 133 or ~he llke, may provide the power for operating punch 127. Alternatively, `~ the punch 127 could have provided there~ith a tank 132l Wh~ch tank has a large enough capacity to complete all the reqlired notch~.ng in a full traverse of one sheet metal ~ length~ and then it could pick up a ne~.r supply o~ air at either end o~ the path of ~ravel, such as by a male member 131~ associated .~ith tank 132' which cooperates w1th a female member 134' at either end of the pa-th of travel, the members 134' being connected up to a lar~e supply tank (such as tank 132~ -Each notcher 125 is moved in the y~direction along ~he edge o~ a mctal sheet to be cut b~ a r~ atable scre~l~rod .

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135 or the like, the rod 135 ~eing rece~ved by a threaded portion of support 136 for the notcher 125. A ~uide rod(s~
137 also should be received by support 136 for guidlng the line~r movement of assembly 125 in ~he y-direction as ~he rotation o~ rod 135 is transformed to transl~tional mo~e~ent by the threaded portion of support 136. A no~cher mo~or 138 is provided for each notcher assemb~y.l25, the motors 138 being controlled by the computer 28 along ~rith the X9 y3 and ~ motors (22g 24, and 26, respectively~. In order to prevent inter~erence ~lth the notcher movement by the guide rollers 105, a leading ~am edge 1~0 ~s provided on each s~de Or notcher 125. The cam edge 140 engages the ball 106 or wheel 107 and moves it in~o houslng 109 agains~ the bias of ~pring 108~ ~he range o~ tra~el of the roller 105 in the housing 109 being large enough to allow the notcher 125 to moYe therepast. Notch~ng can ta~e place simultaneously w~th pattern cutting by tool 14, or after pattern cutting has been completed Op~ionàlly, hinge plates 1~1 may be provided to ~20 cooperate w~th rollers 105 to form ~uide means 30 for in-~uring proper ~lidance of the material into proper cu~ing posi~ion. Hinge ~lates 141~ one being associated ~ith each support 112~ are pivotally mounted ~or 90 movement from a firs~ position wherein the~J are disposed in a subs~antially f`` 25 horizontal plane, supporting sheet metal con~eyed by con~
J veying mearls lo so that lt is rece~ved within the grooves 111 .
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~ormed in the rollers 105, to a second position wherein they are disposed in substantially vertlcal planes and will not interfere with ~peration of notchers 125. Any suitable means, ~Uch as hydraulic cylinders, may be employed for moving the hinge plates bet~een such first and second positions, such means being.sho m schematically at 142 in ~IG. 6 The con-~rol of the hinge plates to move them into the horizontal.
~irst position may be provided by microswitch 65 associated with clamping means 32. When microswitch 65 is not actuated~
the means 1~2 move plate l~l into the hor~zontal first posi-~on, and when microst~itch 65 is actuated - when a metal sheet clamped by means 32 - the means 142 are controlied to move the plates.l41 into the vertical second position s~.nce the ~uiding ~unction thexeof is no longer necessary - 15 . After ~he pattern cutting and notching of a metal Eheet by the assembly of the present invention, the sheet is ; moved atYay fxom the pa~ern cutting position by the conveying means 10 (after release of clamping means 32~ To facili.tate ~ree passage of the pattern eut metal 5heet away from the pattern cutting position, and to facilitate remoYal of the waE~e material that results from cutting~ a roller 145 and was~e b~n 1~6 are provided (see FIG. 1 in particular)0 The r~ller 145 preferably takes khe form of a tube 147 that en~
circles a shaft 148~ the shaft 148 being spring-biased up-~~5 wardly by spring means 149 or the like~ ~nd t~ tube 147 ~' , ' , .' .
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bei.ng loosely disposed with respec~ to the shaft 148, The roller 145 may be spl~t in the middle if desired in order to allow pivotin~ of the clamping member 64 out of the way of the path of the sheet metal during discharge~ howe~er if there is sufficient clearance between the member 64 and ~oller 145, this is not necessary, ~s a cut sheet of metal is moved by the conveying means 10 past member 64, i~ is engaged by roller 1459 and the pattern piece itself may khen be held by an operator or by suitable automatic means as the waste pieces go over the.end of the roller 145 and drop down into the waste bin 146 or the like, The bin 146 preferably has an apex 150 with slanted wa~ls 151 going therefrom whereby cut pieces of metal w~ll slide down out of the way and for periodic collection, FIGURE 6 is a schematic sho~ling of the interrela~ion-~h~p between automatic components o~ the apparatus of the invention, master control thereof beln~ provided by a ~omputer 28. The deta~ls of the computer 28 do not form a part of ~he present invention since any number of conventional computers may be employed ~or performing the control ~unctions necessary ~o practice the invention, The input device may be in the ~orm of a ma~netic tape transport mechanism having coded ~n~ormation utilized by khe com~uter 28 ~hereon~ or a wide Yar~ety o~ other inputs may also be employed, The computer ,~5 28 directly controls the x, Y, ~ a and notcher motors 22, 24 ~ ......................................................... ..
~ .

~ 22 .

.

~ ~ .
26~ and 1389 respectlvely, notcher pistons 1279 the notcher indexers 129, and the clamp release cylin~er 72. Ind~rect control (or supplementary to manu~l control) is also provided ~or clamp compress~on ~ylinder 68, conveyor belt motors 86, ~ccessory sheet feed 153 for the sheet cutting assembly~ and cutter motor 38.
' FXGURE 7,is ~ top diagrar~atic sho~lng of a sheet of metal A in pa~tern cutting positlon that has been cut to ~orm a p~ttern B. The cutter 14 initially penetrated the e~ge C of sheet A at point D, cut llne E3 penetrated edge F
~t point G, cut curve H, and left th'e sheet at po~nt J9 Notches K were formed by notching assemblies 125, the notches K being punched ~hile the pattern B was be~n~ cut. Waste pieces L and M tYere left. ~ , , 15 Apparatus accordlng'to the present invention having been set forth, ~ method of operatlon thereof will now be described. A sheet A of metal ~s fed from an accessory feed-~ng means (153) onto conveyor means 10, which means 10 con-- vey ~he sheet A to a p~ttern cutting position, The suppor~
,20 assembly 112 for guide means 30 ~nd the distance bet~een con~eyor belts 84 have been adjusted to accommodate the Wldth of the sheet A to be cu~ by adjustment ~th handwheels 9~ and 119. The conveying means 10, supporting the sheet A
on flexible tips 100 thereof~ convey the sheet A until it engages m~crosw~tch 65 of clamping means,3~, the ~butment ~'' ' ' , .

~3 ~ 6~
, member 64 preventing further mo~ement of the ~heet A in the y-direction. 2~icros~itch 65 cuts off ~otors 86 power-ing conveyor belts 84 and operates clamping cylinder 68, fir~ly clamping the sheet A in position to be pattern cut~
as well as operatlng motor 81 for s~uaring pin 75 to move pln 75 into abutting engagement with the rear edge of sheet A. The sheet is no~Y held firmly in place by clamp 66, 67, p~n 75~`guide means 30, and tips 100 of belts 84.
With the sheet A in place, the computer 28 ~O ~nitia~es operation of the cutter motor 38 to pro~ide rela~
~ive scissors-like cuttlng movement between blades ~63 37, .the cu~ter 14 penetrates one edge (C ~ FIG, 7) o~ shéet A~
x and y motors 22, 24 ~eing operated by computer 28 to po-si~ion the cutter 1~ at any particular x-Y coordinate within ~he range of suppor~ing means 16~ 189 and ~ motor 26 being operated by computer 28 to orient the blades 369 37 for cut~
. ` ~ing in any particular direction at the gi~en x-y coordinate.
No~cher motors 138 are oper~ted s~multaneously with mo~ors 22~ 2l~ and 26 to position the notchers 125 over selected points along the sheet A, edges C and F to form notches there~n, ~ndexer 129 and air punch 127 being operated at each desired position of notcher 125.
Once cutting of the pattern B from sheet A has ~een completed, computer 28 signals clamp release cylinder ~5 ~2 and cla~p compression cylinder 68~ and clamping pressure 1' ,, .
, . ~ 2l~ ~

6~ .

on ~heet A ~s released, the clamp me~ns 32 is p~voted out of the way of sheet A~ belt motors 86 are res~arted, and the sheet A is conveyed away from the pattern cutting po-~ition thereof over roller 145. .The pattern B is held as ~t passes over roller 145 by an operator or suitable auto-ma~ic means~ and then ls passed on for storage or o~her operations to be performed thereon, the w~ste portions L
~nd M ~rom sheet A.falling inko waste bin 146 As the cut pattern B is being conveyed a~Jay from the cut~er assembly3 ano~her.sheet ~ may be conveyed thereto3 the co~puter 28 opernting the motors 22, 24, 26g 72~ 128, and 81 ~o get all the component parts ~n starting position for cut~ng another sheet A -While the invention has been herein shown and described in what is presen~ly conceived to be ~he mostpractical and preferred embodimen~ of the.invention, ~t will be apparent to those of ordinary sXill in the art that many modifications may be made thereof w~hin the ~cope of the invention; For ins~ance~ while separate sheet feed ls pre~erred, under some circumstances ~t is possible to ~eed sheet me~al from a roll to the conveying means 10~ and cu~ off the roll at the back por~ion o~ the cu~er. Also, a radius wheel 155 wlth counter 156 may be pro~ided associated wi~h cutting means 14 (see FIGJ 2a) Such a radius wheel would act as a measur~ng means and ' ., . , :, ~5 -~09362~

` measure the actual length of an arc cut ~rith cutting means 14, If3 due to variat~ons in the length of the metal sheet ~tock that is used (i~e.~ slightly shorter pieces are fed than the length of pieces planne~ ~or when the computer pro-gram was set~ a radius is cut that is sli~htly shorter than needed, the wheel 155 and counter 156 will detect this, and automatlcally send a signal back to c~mputer 28 ~see FIG. 6)~
which will auto~atically compensate for such a Yariation when the next sheet is cut. O-ther modifica-tions are also ~ossible~ thus the invention ls tQ be accorded the broadest interpretation of the appended claims so as to encompass all e~uivalent stFuctures and meth~ds, , ' _ ~ . '- ' ' .

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26 ......... '~

Claims (6)

The embodiments of the invention in which an exclu-sive property or privilege is claimed are defined as follows:

1. A sheet metal cutting tool comprising an upper blade adapted to be disposed above the surface of a horizontally disposed metal sheet to be cut, a lower blade adapted to be disposed below the surface of a horizontally disposed metal sheet to be cut, and having a leading and trailing edges, means for moving at least one of said blades with respect to the other blade to effect cutting o-f said metal sheet, an arm mounting said lower blade in position below said sheet, and a ball bearing mounted on said arm and having a portion thereof extending upwardly from said arm, said ball bearing being mounted adjacent the trailing edge of said lower blade and for engaging the bottom surface of said metal sheet to allow easier pivoting of said cutting tool during cutting to change the direction of cutting.

2. A sheet metal cutting tool as recited in Claim 1, wherein said ball bearing is spring-biased into engagement with the bottom surface of said metal sheet.

3. A tool as recited in Claim 2, wherein said arm is relatively stationary and wherein said upper blade is reciprocated with respect to said lower blade.

4. A tool as recited in Claim 2, wherein said arm is a lever pivotal about a generally horizontal axis during horizontal cutting at a pivot point, said ball bearing being mounted adjacent said pivot point on one side thereof and the trailing edge of said lower blade being mounted adjacent said povot on the other side thereof opposite the side said ball bearing is disposed.

5. A tool as recited in Claim 2, wherein said lower blade is movable with respect to said upper blade by pivoting said blade about said pivot.

6. A tool as recited in Claim 5, wherein said upper blade is reciprocal with respect to said lower blade, relative movement of both blades effecting cutting of said metal sheet.