CA1072003A - Sheet metal cutting - 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 ? 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 notchers being adjust-able with respect to each other to accommodate sheets of different widths. The x, y, ?, and 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 pattern cut from the sheet being supported while the waste portions of the sheet fall into a waste bin or the like.

Description

~L~726~33 - BACKGROUND AND SUMMARY_OF THE INVENTION
The invention relates to a method and apparatus for automatically cutting sheet metal into pa*terns for forming ductwork, etc. Conventionally, such pattern cutting of sheet metal is done b~ hand, and is very labor intensive, relatively slow, and requires a large number of skilled la-borers to achieve acceptable large volume p~oduction. While systems are known for cutting sheet material in general in-to patterns, such systems really have not been adapted so that lo ~hey could function in cutting sheet metal of a wide variety - . .
of gauges and widths as is necessary when pattern cutting ~ `
sheet metal for making ductwork9 etc.
A number of prior art devices made by Gerber Garmen-t Technology, Inc., such as shown in U.S. Patent Nos. 3,477,~22, 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 em-ployed by such devices do not, it is believed, provide for -~
easy adaptaton to cutting of sheet me-tal, and large production thereby is usually based on cutting a large stack of sheets all at the same - - not practical with sheet metal --rather th ~ by automatic conveyance of the sheet material into a cutting position.
According to the present invention, automatic pattern cutting of sh~et material is practical; something ~'~
:' . -,.
:

2 ~

~ '.
: ~, ... . ... ..... . ... . . . .. . .

;
~72~3 ` ::
that heretofore has no-t been praetical. According to the present invention a metal sheet is automatically conveyed by conveying means into a pattern cutting position, guidance ~
thereof being provided, and the metal sheet is then auto- ~ i matically clamped into place at the pattern cutting posi~
~ tion. A cutting means, which preferably coMprises a shear `~ cutter, one blade thereof being adapted ~o be disposed above the horizontally disposed metal sheet, and the other blade thereof being adapted to be disposed below the horizontally disposed metal shee~. Supporting means associated with the conveying means support the metal sheet in proper position to allow positioning 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 operation. The pattern cutting is controlled by a computer which activates means for moving the cutting means to any x-y coordinate of the horizon-tal metal sheet, and ;~-activates a motor for moving the cutting blades to any angu~

; lar, a~, position.
: ;' .:' The cutting means cuts into the metal sheet through a free edge thereof, and cuts any desired pattern.~
A ball bearing can be provided associated with the lower~~ ;`
blade member to aliow more exact control of the angular , position of the cutting means ~especially when right angles or tight curves must be cut). After cutting of the desired pattern from the metal sheet~ the clamping means are auto-matically released, the conveying means s~arted, and the`~ ~`

'`~
: ""

' ~' ~C~7;~ 3 ;~ sheet moved away from the pat-tern cuttingr~positi.on. The sheet ~.ay be pas~ed over a roller and the pattern held on the roller while the waste cuttings fall into a was-te -bin disposed below the~roller. ~ `
Notchlng of the metal sheet being pattern cu-t can also be effected automatically~ notches often being necessary at predetermined locations along the edges of a pa-t~ern to allow for folding of the sheet to form ductwork~ ;
etc. Notching is effected by a notching assembly movable along each side edge of the metal sheet, the notching assem-blies receiving the sheet between top and bottom plates thereof. The notching assemblies are controlled by the com- ;;
puter also, as i~ an indexer for each for bringing a selected ~ ~;
one of a plurality of notching dies into operative relation-ship with the notching punch. The notching assemblies are movable with respect to each other in the direction perpen-dicular to the feed direction of the metal sheets to accommo-date sheets of different widths, and shims may be provided `
therewith to accommodate sheets of differ~nt gauge.
It is the primary object of the present invention to provide a method and apparatus for effecting the auto-matic pattern cutting of sheet metal. This and other ob-jects of the invention will become clear from an inspection o~ the detailed description of the invention, and from the - appended claims, ' '' `~

.. ' .
'' ' ::

3 ~:
.. :

BRIEF DESCRIPTION OF THE DRAWINGS
FIGURE 1 is a perspective view of exemplary apparatus for automatic pattern cutting of sheet metal -according to the present invention; :
FIGURES 2a-2c are perspective, side, and top ~ :
views, respectively, of an exemplary cuttîng means utiliz~ ~:
able according to the present invention, and FIGURE 2d is a side view of a modified form of cutting means that could ;
be employed in the apparatus o~ FIGURE 1;
FIGURE 3 i8 a detail view of clamping means util- ~:
izable in the apparatus of FIGURE 1 for holding a metal sheet to be cut in pattern c~tting positîon; :;
FIGURE 4 is a detail perspective view of exemplary conveying means utilizable in the apparatus of FIGURE l; :
FIGURE 5 is a detail perspective view of an~exèm~
plary notching assembly according to the present invention, with guide means cooperating therewith;
FIGURE 6 is a schematic diagram of the interrela- :
tionship between controlled and controlling components ac-.. 20 cording to the present invention; and FIGURE 7 is a top diagrammatic view of an exem-plary metal sheet after pattern cutting thereof according ~.
to the present invention.

.; : , : -5 - .

33 : ~

DET~ILED DESCR~PTION OF THE INVENTION
An exemplary automatic sheet metal cutter accord- -ing to the present invention is shown in FIG. 1. The appa~
ratus according to the present invention includes the maior .
components of a conveying means 10 for conveying a sheet of ~ ~
metal to be pattern cut into a pa-ttern cutting position ~ :
tsee FIG. 7) 7 the conveying means 10 having supporting means 12 associated therewith for supporting the 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 shearing the ~heet of metal to pattern cut it, means 16, 18 for supporting the cutting tool means 14 above the sheet of metal to be pattern cut :
so that the cutting tool means 14 is in operative cutting ~:
position with the sheet of metal, and so that the cutting ; ~
tool means 14 may be moved in x and y horizontal directions : :
substantially perpendicular to each other, means 20 for sup~
porting the cutting tool means for substantial 360 angular :
a~_ movement about a vertical axis z, an x mo-tor 22, a y . ~-~
motor 24~ and ~_motor 26 for automatically moving the cut~
ting tool means 14 in the x, y, and ~ directions, respectively, computer control means 28 tsee FIG. 6) Eor automatically con~
trolling the operation of the x, y, and ~ motors 22, 24, and 26, respectively, ~or moving, the cutting tool means 14 to cut a desired preprogrammed pattern from the metal sheet, .'". ' ~,:

6~

1. ~

7~ 3 guide means 30 for guiding ~he movement of the sheet into pattern cutting position, and clamping means shown gen_ ;
erally at 32 and 34, for holding the sheet of metal sta~
tionary at its pattern cutting position during pattern cutting thereof. Each of theindividual components of -the sheet metal cutter may take a number of ~orms to accomplish `;~
pattern cutting of the shee-t metal, the following specific embodiments thereof merely being preferred.
The cutting tool means 14 is shown in more detail in FIGURES 2a-2c. The actual cutting portion o~ the means 1l~ includes a pair of blade members 36, 37 for shearing of the metal sheet received therebetween, one blade member 36 `
being disposed above a horizontally arranged piece of sheet metal to be cut andsshearing the metal by penetrating through the top surface thereof, and the other blade member 37 being disposed below the horizontally arranged piece o~ sheet metal and shearing the metal by penetratin~ through the bottom surface thereof. The exact structure of the cutting portions may be varied -- for instance only one oP the blade members 36, 37 may be mo~ed during cutting, or both may be moved during cutting -- however one exemplary cutter that may be adapted for use in the present invention is sold under the name Unishear, and is manufactured by Black and Decker. A motor 38 powers the movemen-t of tlle blade 36 during cutting, and in the embodiment shown in the drawings .. '~ , .

,. .~ . .
., .:

:''' "; , ' ." :. .' ' ,:

lB7;Z~03 moves upper blad~ member 36 downwardly while blade 37 re-mains stationary. An arm 39 mounts blade member 37, the arm 39 having a leadîng portion 39' thereof, and a gener- -~
ally flat upper surface for engaging the bottom of the sheet.
A stationary guide member 14, which allows reciprocation of blade 36 -therein and moun-ts arm 39, has a V-notch formed in the front end thereof, being so shaped to facili~te move-ment of the sheet metal to be cut into position between the blades 36, 37. The member 41 has only a t~in vertical por~
, .
tion 42 connecting the enlarged upper and lower portions thereof which are adapted to be d~sposed above and below the sheet of metal to be cut, thepp~rtion 42 being adapted to pass through the cut made in the metal sheet by the cutting -;
blades 36, 37. According to an important aspect of th~ pres- ~ -entlinvention, a ball bearing 43 (which may be spring-mounted) is provided on arm 39 adjacent the trailing edge of blade 37 = ,~
. ~
for engaging the bottom surface of the sheet ofr~lmetal to be pattern cut to facilitate powered movement of the cutting portion through the sheet metal. This is especially import~
.~
ant wherein sharp turns are necessary during pattern cutting, especially since the~c~t~îng operation is automatic. The `~
ball bearing provides a point of engagement on the metal ~`
sheet to allow for sharp rotation of the cutting tool means - `
:: :
14 about the vertical axis z. It is noted that the ball bearing arrangement may be provided on any cutter, a hand :`
'';' ~'' ~7Z~3 ~
, .: , automatic cutter, 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 pivot point 40, and the motor 38 could both recip~
rocate blade 36 and pivot lever 39, resulting in a simultaneous --movement of the blades toward eaoh other during cutting. The ball bearing 43, in such a case, would be disposed adjacent ~i pivot 40 on the opposite side thereof as blade 37.
The motor 38 of the cutting tool means 14 is mounted within a housing 44 on a shaft 45, a bearing 46 being provided on the top of the,~motor 38 for receiving shaft 45, and a bear~
ing 47 bei~g~pro~ided,~on~-th~bot~om of th~,,motor 38 for receiv- ~, ~ ing shaft 45, the shaft 45 being directly connected to station- '' ary member 41 mounting the blade members 36,337. The housing 44 is stationarily mounted on a cross-member 48 which is part ~ of moun-ting means 20, as b~ keys 48~, which cross-member 48 :~, also mounts the~ motor 26 for rotating the cutting tool means `~-" in the a direction. Although any suitable arrangement may be utilized, it is desired tha-t the stepping a motor 26 turn a , --'~ 20 worm 49 through a gear box 50, which worm 49 in turn rotates ' gear 51 attached to the top of shaft 45, the gear 51 and shaft 45 being rotatable about the z axis. Signals to a ~otor 26 ' during the pattern cutting operation will cause rotation of ~?, the shaft 45 to position the cutting blades 36, 37 in the , correct position for cutting of the desired preprogrammed -~
pattern.
' .,',"'~., ;~ "i , .
_9_ ~

`',.: ~ '.

~al7Z~3 :~ ~
~ .

While the scissors-type cut-ting tool described above with reference to FIGS. 2a~2c is preferred, for cer- ;~
tain heavier gauge sheet steel, it may be necessary to use a nibbler-type cutting tool to effectively cut patterns in ;~
the sheet metal. Such a nibbler-type cutting tool may have a head like that shown in FTG. 2d at 52. The head 52 in-cludes a punching portion 52~ that reciprocates up and down, punching a small hole with each reciprocation. A slo-tted plate 5l~ is provided on the head 5Z below a sheet of metal to be cu-t to insure proper punching of a plug of metal while the ~urrounding metal is not disturbed. The nibbler he~d 52 may be interchangeable with the scissors-type cutting head shown in FIGS. 2a-2c, a releasable connection being provided at 53, or the whole motor and cutting head arrangement may be re-placed when it is desired to change from nibbler to scissors cutter and vice versa. In such a case, the nibbler motor will also have keys 48' associated therewith, and it may merely be ~-slipped into operative engagement with cross-member 48 after thesscissors-type cut-ter is removed. Other type cutting heads could also be employed, depending upon the type of material to be cut.
The cutting means 14 is mounted by mountingri~means 16 and 18 for movement to any particular coordinate of the area covered thereby. The mounting means 16 includes a pair ~ ;
of end members 55 defining the outer extremities of movement in the x-direction, the,members 55 being connected ~y one or ~ more guide rods 56 and a screw-rod 57 or the like. A threaded ~ ;~
;~ member 58 of mounting means 20 receives the screw-rod 57 ~ therein and transform the rotational movement of the screw~rod ,~

- 1 0_ , . .

1~7263 ~3 ~:
,, 57 to linear movement of the mounting means 20 for cutting tool 14, which linear movement is guided by the smooth ; -;
guide rod~s) 56, x stepping motor 22 is mounted on one of the end members 55, and rotates the screw-rod 57 in response ;
to controls from computer 28. ;
The mounting means 18 includes a pair of frame members 60 disposed on either end o~t~ea~h:and member 55 of the mounting means 16, each pair of frame members 60 ~ :
having one ~or: more guide rods 61 disposed therebetween as well as a screw-rod 62 disposed between one pair ~or both pairs) of frame members 60. The end members 55 of the mounting means 16 receive the guide rod(s) 61 therein, and one of the members 55 has a threaded portion receiving the screw-rod 62 to transform rotational movement of:the:screw-rod -62 into translational movement of the members 55 in the ~ .
:
y direction. The y stepping motor 24 is mounted on one end of the frame members 60 for rotating screw-rod 62, and ~` `
rotates 62 in response to signals ~ed to it by computer 28. . .
lt is noted that each oP the pairs of the frame members ~.:
60 must be spaced far enough apart (in the x-directi~n) so . :~ :
. . .
tha* the scissors blades 36, 37 of theicutting tool can in-itially engage a side edge of the me-tal sheet to be cut in order to begin cut~ing thereof. Alternatively, the bottoms of the frame members 60 could be located relatively close to the proposed edges of the largest sheet ofmmetal to be re~
ceived by the whole assembly, and the top portions of the :~.
frames 60 could then be flared out a large enough distance :
to allow movement of the cut*er tool 14 into proper starting : :~
position.

, ':

:
'~ .`

7~0~33 ~ hile theemounting means have. been described with reference to screw-rods for providing movement of the members 55 and 20 thereof, of course other means could be provided , such as a rack and pinion arràngement or the like.
The clamping means 32, 3L~, which hold the sheet of metal to be cut stationary in a pattern cu-tting position, ;;
may also take a wide variety of forms; however a preferred .~
form of the clamping means 32 is shown in FIG~ 3. The clamp- ~^
ing means 32 includes an abutment member 64 for stopping for- :
ward moveme~t of the sheet metal, which member 64 has a micro~
switch 65 or the like mounted therewith. A piston member 66 ~;
is movable upwardly in response to sensing of the sheet metal position by the switch 65, and clamps the sheet metal against :~
the upper surface 67 of member 64. Shims could be provided `~
for surface 67 to adapt it to a wide range of gauges of metal -to be pattern cut. The cylinder 68 for moving the piston 66 in response to a signal from switch 65 may be any suitable ~ :
type, such as pneumatic, hydraulic, electrical, or the.,lI~e. ~:.
The whole assembly associated with member 64 is mounted on a tube 69 for pivotal movement about shaft 70 which is re~
ceived by tube 69. Gussets 71 may be provided for connecting the member 64 to tube 69 to minimize the strain on the member 64 from clamping engagement of sheet metal. A power means, such as cylinder 72, is pro~ded attached to tube 69, such as ~ :~

~ .

~ -12~

~6~7z~ 3 by:llever 73 and ~levis pin 74, to provide for pivotal move- i ment of the member 64 with respect to the sheet metal to move the clamping means 32 out of the~?path of travel of the sheet metal after pattern cutting thereof has been completed and clamping thereof has been released. The cylinder 72 is also preferably controlled by the computer 28, and the com-- puter 28 also preferably provides a dual control (with micro switch 65~ for the cylinder 68, the.::oomputer 28 ;nitiating pivoting movement of the means 32 and releasing of the clamp 66,67 after pattern cutting of a sheet is completed.
: It;is also desired that an arrangement 34 be provided - on the opposite end of the metal sheet to be cut from the clamp~
ing means 32 to assist in holding the sheet in position during cutting thereof. Such means 34 preferably takes the form of one or more motorized squaring pins 75 or the.~like~ see FI~S.
1 and 4). Pin 75 is preferably pivotally mounted at 76 on a support 77, pivotal motion thereof in the direction of feed : -of`the metal sheet against a spring bias being provided to `
allow movement thereof out of the way of -the metal sheet;
. 20 however after movement of the sheet therepast, the pin 75 re- :
turns to its vertical position, and is prevented by stop 78 ~;; from pivoting in the opposite directîon of sheet feed. Sup- .
port 77 is internally threaded and receives screw-rod 79 therein, and is also connected to guide rod 80, rotation of screw-rod 79 by motor 81 being transformed into transverse movement of pin 75 by support 77, After movement of the '` -.
. ~ .
, ~
-13- :

--` 1(~17Z~3 sheet metal therepast, when -the pin 75 is returned to its ~u vertical position~ the motor ~1 is activated (i.e., automati-cally, controlled by computer 28) and it moves the pin 75 ;: :
into abutment with the back edge of the metal sheet, stop 78 ,. . .
preventing pivotal movement of pin 75 in response to such abuttin engagement. The pin 75 thus assists the clamping means 32 in holding the sheet material in a sta-tionary pat-tern cutting position during pattern cutting thereof. -Conveying means 10 preferably comprises a number ln o individual conveyor belts 84 spaced from each other in the x-direction, although one large conveyor belt could be pro- -~
vided ~if the guide means 30 adjustment were properly arranged). i Each conveyor belt 84 extands substantially the length of the y distance between the frame members 60, and is powered by a powered roll 85 rotated by a motor 86 or the like. At least . : .
one other roll 87 besides powered roll 85 is provided, mounted at the opposite end of the conveyor belt 84 from roll 85, both rolls 85, 87 being rotatable about a hori~ontal x-aY.iS~ A
- frame 83 is provided. A belt tension adjustment means 88 may ` -1 20 be provided to insure powered movement of the conveyor belt during all types of load conditions. Also, it is preferred tha* the individual conveyor belts 84 be movable in the x-direction with respect to each other to accommodate metal sheets of varying widths. For instance, if two conveyor belts 84 are provided, they may be mounted for mo~ement to ~

~ .:
'' ..~:

~' `'~ '', ,. ;, "::
~ , .. .
_14- ~;

~ ':

~L~7Z~

engage portions on either side of the metal shee-t to be ~ .
transported thereby, the amount of gap provided between conveyors 84 being determined by the size of the metal ,-sheet. Should such a gap become too large, of course a third conveyor belt 84 could be provided. Means for moving the conveyor belts 84 with respect to each other in the ' x direction may talce a wide va~iety of forms, such as that shown in FIG. 4 generally at 89 for moving one belt 84 while the other belt tcut away in FIG~ 4) remains sta*ionary 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 85, 87, the wheel carriage 90`ha~ing~a"~
middle portion 93 thereof that îs threaded to receive a screw-rod 94 therein. The screw~rod 94 may be rotated by any suitable means, such as gear 95 powered by chain 96 and hand-wheel 97, the portion 93 transforming rotational move-ment of the rod 94 into transverse movement of the carriage ', 90 in the x-direction. Of course a wide variety of other .... ..
, means could be employed, such as a rack and pinion and motor-: 20 ized chain-wheel~ It is noted that the clamping means 34 is disposed adjacent the stationary belt 84, at the end of~ ~
travel of the nlovable belt 845 so taht it does not interfere ' with the movement of the bel'ts, nor they with it. Of course, ' both belts 84 could be made movable, with a common screw-rod ,-~
94 being provided for powering each of t~èm from a middle '~

1~7~003 ;~ position to end pos~tions~ and ~he means 34 would be dis--posed bet~een the belts 84 at the middle sta~ionary position thereo~. Control of motor 86 may be effected manually, by ' m~croswitch 65, and by computer 28 , ' The supporting means 12 associated with the con~
~eyin~ means lO'provide suppor~ o~ shee~ metal moun~ed thereon ~n a manner to pre~rent damage to the conYeying means 10 dur-~ng pattern cutting of a metal sheet by the cutting tool 14.
The supporting means l? pre~erably ~ake the form o~ a plur-ality of tips 100 removably mounted on conveyor belts 84 - oYer the whole length thereof~ and spaced close enough to~
ge~her to provide for secure support of a metal sheet on the ; tops 103 thereo~. Each tip 100 is ~ormed o~ hard rubber or ~` other sturdy but flexible material, and may be connected to ~,' 15 the conveyor 84 by'scr,ews 101 and the like9 rece~Yed by in-terior threaded portions 102 of the tip 1~07 The tips 100 ~re high enough ~o allow passage of the lower blade member ~' 37 and associ~ted structure of the cutting tool 14 between the metal sheet and ~he top of belt 84 so that no damage results to belt 84 dur~ng cutting. Since the tips are elon~ated and generally in the shape of a truncated cone, and are made o~ flexible material, they will flex ou~ o~
' the way when engaged by the leading edge o~ leYer 39 and/or ~, - the leading edge of member 41 ~or the plate 54) as the cut-~ 25 ~ing tool 14 is moved around, whereby damage to them will 3 ~J also be pre~ented; If` ~ome damage does occur to some tips 100, however, the dam~ged tips may be peri~ically replaced.
' . ''''' ''` ' ' .

~ 16 l~J20~3 ., .
~- The guide means 30 ~or guiding the movement of ~he sheet metal in~o pattern cut~n~ pos~tion preferably include a plurality o~ gu~de rollers 105 mounted along either side o~ a metal shee~ to be cut~ and in abutting~
xeceiving engagement there~ith. Whlle the rollers 105 may ~ake a ~ide variety o~ ~orms, it is pref~rred that they be in the ~orm of a ball 106 or trunc~ted wheel 107~ spring b~ased into engagement with a side edge o~ metal sheet by a spring 108 or the like. ~uided linear movement of the ball 106 or truncatéd wheel 107 in housing 109 therefor is pro~ided by any suitable guide means, such as pins 110. Each gu~de roller 105 has a ~roove lll formed therein, the groove ~: 111 being wide enough to receive the largest gauge sheet metal to be cut there~n. Sh~ms may be provided for the . . .
groo~es 111 i~ desired. In addition to providing guidance or the movement of the metal sheet into pattern cutting . .i .
~` posit~on5 the means 30 also serve to hold the sheet in place dur~ng cutting -- acting in con~unction with conveyor tips 100, and clamps 32 and 34 ~n this regard.
The guide rollers 105 on one side o~ a metal sheet to be cut are mounted on a support assembly 112 that ~s mov~ -~ble in the x-direction to accommodate metal sheets o~ differ ent widths. A pre~erred means for movably mounting the a~sembly 112 is sho~ln in ~IG. 1 generally at 113, this ~eans ;25 113 belng similar to the means 89 for moving the conveyor ~ .. ..
.
,~ .

- 17 ~

~ 03 bel~s 84 with respect to each other, The means 113 in-~_ .
~ ^j cluaes a pair of end collars 114 ~or mountlng a~sembly 112, , e~ch collar 114 receiving a guide rod 115 and a screw-rod .116~ ~ threaded interlor portion being provided ~or the portion of collar 114 r ceiving rod 116 to trans~orm ro-tational movement of rod 116 ~nto translational mo~ement ln ; the x-direction. The screw-rods 1~6 may be driven by any ~u~table means such as gears I17 mounted on the exterior extrem~ties thereo~, rotated by a chain 118 dxiven by handwheel 119.
In ~ddition to mounting the guide rollers 105~
. each ~upport assembly 112 also ~upports a no~cher a~sembly 125 which is rec~procal with respe~t thereto (and with respect to a metal sheet in pattern cutting position) ~n the y-direction, The notcher assemblies 125 ~re for making notches in ~he side ; edges o~ the metal sheet to facilitate bending o~ the pattern cut therefrom along lines between the notches. ~ach notcher - 125 com~rises ~our main components, a guide 126 ~or ~eceiving ~he shee~ edge to be notched therein~ a punch 127 - which may ~ 20 be either pneumaticaliy or hydraulically opera~ed - which - . ~upplies the punching force ~or notching, a plurality o~
notching dies 128~ one of which at a time is contac~ed by ~he punch 127 to move throu~h the top plate of the ~uide 126 Rnd ~orm a notch in the metal sheet edge, and ~n indexer 129 for selecting ~hich die 128 w~ll be~.used to form a given no~ch, Alth~u~h the punch 127 could be made movable to position itsel~

v .. .

. . . .

`

"', ,' '` ,'' ~ ` . . . .
... ~ . . . . .
, .
o~er any one of the dies 128, ~t is preferred that the punch 1~7 remain stationary wh~le the dies 128 are moved by the indexer 129 into operative position with the punch 127, In-dexing o~ the d~es 128 may be provided by a w~de varie~y of 5- in~exers~. such as a linear one ~or movin~ d~es 12~ mounted in a linearly movable plate~ however the geneva wheel 1~0.
ls pre~erred~ the dies 128 being mounted around ~he periphery o~ wheel I30~ and indexer 129 movin~ one posit~on each ~ime to rotate a selected die.l28 into proper position beneath . punch 127. The guide 126 may have a removable shim(s) 131 asso~iated therewi~h to adapt to metal sheets o~ different gauge ~o insure tha~ the sheet is held in place properly dur-ing notching. A tank of compressed air l32 or the like, con-nect~d to punch 127 by a reelable hose 133 or the like~ may proYide the po~1er ~or operating punch 127.. Alternatively, the punch :127 could have provided there~ith a tank 132' which tank has a large enough capacity to complete all ~he required notching in a full traverse of one sheet metal length, and then it could pick up a new supply of air at either end of the path of travel, such as by a male member 134 associated with tank 132 ! which c03perates with a female member 134' at either end of the path o~ travel~ the members 134' ~elng connected up to a large supply tank ~such as tank 132~. ~
. Each notcher 125 is moved ln the y-d~rect~on along the edge of a ~et~1 sheet to be cut by n r~ atable screw-rod .

~ 0~3 .

.
" `` 135 or the l~e, the rod 135 being rece~ved by a threaded p~rtion of support 136 for the notcher 125. ~ guide rod(~) 13~ also should be rec~ived by support 136 for guiding the linear movement of assembly 125 in the y-direct~on as the ~otation of rod 135 ~s trans~ormed to translational movement b~ the threaded portion of support 136. A notcher motor 138 is provided for each notcher assembly.l25~ the motors 138 be~ng controlled by the computer 28 along with the x~ y, a~d ~ motors (22~ 24, and 26~ respecti~ely)g In order to prevent interference with the notcher movement by the guide rollers lOS, a leading cam edge 140 ~s provided on each side o~ notcher 125, The cam edge 140 engages the bali 106 or wheel 107 and moves it into housing 109 against the bias of ~pring 108, the range of tra~el o~ the roller 105 in ~he housing 109 being large enough to al~ow the notcher 125 to move:therepast. Notching can take place ~imultaneously wlth pattern cutting by tool 14~ or after pattern cutting has been completed, Opt~onal~y, hinge plates 141 may be provided to cooperate w~th rollers 105 to form guide means 30 for in-6u~1ng proper guidance of the material into proper cutting posl~ion, Hinge plates 141, one being associated with each support 112, are pivotally mounted f`or 90 movement from a - ~irst position wherein they are disposed in a substantially ; horizontal plane, supporting sheet metal conveyed by con-~J veyin~ means 10 so that it is recelved within the groo~es 1 ,~ ?

- ~ 20 ~

., ; , .
, , ' ' ' ' '.
~07~003 .~ . ~ . .
' ~ormed in t~e rollers 105, to a second posit~on whereln they are ~isposed in substantially vertlcal planes and will not inter*ere ~th operation of notchers 125. An~ suitable means, ~uch as hydraulic cylinders, may be employed for mo~ing the . hinge plates bet~een such flrst and second posi~lons, such . means being.sho-~n schemat~cally at 14~ in FIG. 6. The con-trol o~ ~he hinge plates to move them into the horizontal.
rst position may be provided by microswitch 65 associated .
w~th cl~mping means 32. When microswitch 65 ~s not actuated, - ~0 ~he means 142 move plate 141 into the horizontal first posi-tion, and when microswitch 65 ~s actuated - when a metal sheet iB clamped by means 32 the means 142 are controlled to move ~he plates 141 into the ~ertical second position since the guiding function thereof is no longer necessary.
A~ter the pattern cutting and notchin~ o~ a metal heet by the assembly o~ the present inYention, the sheet is mo~ed a~Yay from the pattern cutting position by the conveying ~eans 10 (af~er release of clamping means 32). To ~acili~ate ~xee passage o~ the pattern cut metal sheet away ~rom the 20- pattern cutting position, and to fac~litate removal of the . wa~te material that results from cutting, a roller 1~5 and wa~te b~n 1~6 are pro~ided (see FIG~ 1 ln particular3. The roller 145 preferably takes the ~orm of R tube 147 that en-c~rcles ~ shaft 148, the sha~t 148 being ~pr~ng-biased up~
wardl~ by spring means 149 or the like~ and the tube i47 ~."--~ ,........................................................ .
: ,~ ' ' ,-, ,~ .
. 2~ . .
~ -, ., ~
. .. .

, .. , ... .. . - . .. ... ; . .... ~.... ... . .

1~20~3 ' t._ `
,S being loosely dlsposed with respect to the shaft 148. The roller 145 may be ~plit in the middle ~ desired in order to allo~ pivot~ng of the clamping member 64 out of the ~ay : o~ the path of the s~lee~ metal during discharge, however i~
there is su~icient clearance between the member 64 and ~oller 145, t~iis ~s not neeessaryO As a cut sheet o~ metal moved b~ the convey~ng means 10 past member 64~ i~ is enga~ed ~y roller 1~5, and the pattern piece ~tself may then be held by an operator or by suitable automatic m~ans a~ the waste pieces go over the end o~ the roller 145 and drop down . in~ the waste bin 146 or the like. The bln 146 pre~erably has an apex 150 with slanted walls 151 going therefrom whereby . cut pieces of metal will sl~de down out o~ the ~Jay and for , periodic collection, ` 15 FIGURE 6 is a schematic sho~ring o~ the interrelation-Ship between automatic components of the apparatus o~ the in~ent~on9 master control thereof being provided by a computer ; . 28. The det~ils of the computer 28 do not ~orm a part o~ ~he ~: present invent~on since any number of conventional computers may be employed ~or performing the control functions necessary ; . to practlce ~he invention. The lnput device may be ln the form of a magnetic tape transport mechanism having coded in~ormation utilized by the computer 28 thereon, or a wide ~arie~y of other inputs may also be employed, The computer f~5 28 directly controls the xg yg ~ , and notcher motors 22~ 2 ~ ,.

w 22 ~
.

.

~ Z~03 ~ .
.
'~ 26~ and 138, respectively, notcher pis~ons 1279 ~he notcher indexers 129, and the clamp release cylinder 72l Indirect control (or supplementary to manual control~ ~ also provided ~or.clamp co~pression cylin~er 68, conveyor beIt motors 86~
accessory sheet feed 153 ~or the sheet cutting assembly~ and cukter motor 38.
. FIGURE 7 is ~ top ~iagrammatic sho~Ying o~ a sheet o~ metal A in pattern cutting pos~tion thak has been cut to ~orm a pattern B. The cutter 14 in~tially penetrated the ~dge C o~ sheet A at po~nt D, cut llne Eg penetrated edge F
: a~ point G, cut curve ~ and left the sheet at point J.
Notches K were formed by notching a~semblies 125, the notches K being punched wh~le the patte~n B was being cut. Waste pieces L and M were left.
: 15 . Apparatus according to the present ~n~ention having been se~ ~orth, a method o~ operatlon thereo~ will now be : dsscribed, A sheet A of metal is fed from an accessory ~eed-lng means (153) onto conveyor means 10, which means 10 eon-Yey the shee~ A to a pattern cutting positionO The support assembly 112 ~or guide means 30 ~nd the distance between conYeyor belts 84 have been ad~usted to ~ccommodate the width o~ the sheet A to be cut by adjustment ~ith hand~heels 97 and 119. The conveying means 10, supporting the sheet A
on flexible tips 100 thereof, convèy th~ sheet A until ~t 25 . engages microswitch 65 o~ clamp~ng means 32~ the abutment ~ ' "' ,: "

: ~ 23 - . .

.. ...... . . ... . . .. . ... .

107~03 .
~ember 64 preventing further movemen~ o~ the ~heet A in ~he y-dlrection. ~icroswitch 65 cuts off motors 86 power-ing con~eyor belts 84 and operates clamplng cylinder 689 ~irmly clamping the sheet A in position to be pattern cutg ~s well as operatlng mo~or 81 for ~quarlng pin 75 to mo~e pin 75 into abuttirlg engagement with the rear edge of sheet A. The sheet is no~ held ~irmly in place by cl~p 66, 67, pill 759 guide means 309 and tips 100 of belts 84.
. , , ~ .
~t~ the shee~ A in place, the computer 28 : 10 ~nitiates operation o~ the cutter motor 38 to pr.ovide rela-tive ~cissors-like cutting mo~ement between blades 36~ 37, .~he cutter 14 penetrates one edge (C - FIG, 7) o~ sheet A, x ~nd y motors 22~ 24 being operated by compu~er 28 to po-s~tion the cutter 14 at any particular x-Y coordinate within the range o~ supporting means 16, 189 and ~ motor 26 being perated by computer 28 to orient the blades 36, 37 for cut-ting in any particular direc~ion at the given x~-y coord~nate, N~cher mo~ors 138 are operated slm~ltaneously with ~otors . 229 24 and 26 to position the notchers 125 o~er selected points along the sheet A, edges C and F to ~orm notches therein, indexer 129 and ~ir punch 127 being operated at each desired position of notcher 125.
Once cutting of the pattern B ~rom sheet A has been completed, computer 28 signals clamp release cylinder ~ 25 72 and clamp compression cyl~nder 68, and clamping pressure -,'(~ ` , ' , , .

.
~ . .

~O~Z~03' .

.
',f~ on sheet A ~s released, the clamp means 32 is pivoted out of the ~ray o~ sheet A~ belt motors 86 are restarted, and the sheet A is con~eyed away ~rom the pattern cu~ting po-sit~on thereof over roller 14~, .The pa~ern B ~s held as i~ passes oYer roller 145 by an operator or su~table auto-ma~c means~ and then is passed on ~or storage or other operations to be per~ormed thereon~ the wast-e portions L
and M ~rom sheet A falling into waste bln 11~6, As the cut pattern B ls being con~eyed a~lay ~rom the cut~er assembly, anQther.sheet A may be con~eyed thereto~ the computer 28 operating the motors 225 24~ 26, 72, 128, and 81 to ge~
a~l the component parts in starting position ~or cutting another sheet A.
. ~hile the inven~on has been herein shown and described in what ~s pre~ently concei~ed to be the most ~ract~cal and preferred embodimen~ of the.invention5 ~t w~ll be apparen~ to those o~ ordinary skill in:the art that many modifications may be made thereo~ within the ;-?
scope o~ ~he inYention. For instance, while separate ~heet ~eed is pre~erred~ under some c~rcumstances it is possible to feed sheet metal from a roll to the conveying means 10~ and cu~ off the roll at the back portion o~ the ~utter. Also, a radius wheel 155 with coun~er 156 may be pro~ided assoc~ated with cu~tin~ meàns 14 (see FIG. 2a), `~ ~5 Such a radius wheel would act as a measuring means and ~ , .. .

~ ~5 ~
.

~0~03 measure ~he actual length o~ an arc cut wi~h cutt~ng m~ans lfg due to variations in the length Or the ~et~l sheet stock that is used (i.e., slightly shorter pieces are ~ed than the length of`pieces planne* ~or when the computer pro-5 gram was set) a radius is cu1; thak is slightly shorter thanneeded~ ~he wheel 155 and counter 156 ~11 detect this, and au~omatically send a slgnal back to c~mputer 28 (see ~IG. 6), ~hich wili automat~cally compensate ~or such a ~ariation when ~he next sheet is cut. Other modifications are also poss~ble, thus the invent~on is to be accorded the broadest ~nterpreta~ion of the appended claims so ~s to encompass all equi-~alent structures and methods.
. , ' , :, ' . . : ;
' ' ' ' ' :
, . . .

, ,' ~ , .

,~ .

"

. ~ 26 ~
.
., ~ , . - ..

Claims (33)

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

1. Automatic sheet metal cutting apparatus for cutting patterns and the like from sheets of metal fed to said apparatus in a feed direction, said apparatus compris-ing a scissors cutting tool means having a pair of blades, one blade being adapted to be disposed above a horizontally arranged metal sheet to be pattern cut, and one blade being adapted to be disposed below said metal sheet, conveying means for conveying said metal sheet into a pattern cutting position, said sheet being disposed in a horizontal plane, supporting means being associated with said conveying means for supporting said sheet so that said cutting tool means may cut through an edge thereof when pattern cutting is initiated and may pattern cut said sheet without damaging said conveying means during pattern cutting, means for supporting said cutting tool means above said conveying means, in a position wherein said blades will be disposed above and below said sheet in a horizontal plane, and for movement in x and y horizontal directions substantially perpendicular to each other, and allowing access of said cutting tool means to at least one free edge of said sheet, means for supporting said cutting tool means for substantially 360° angular, ?, movement about a vertical axis, x, y, and ? motor means for automatically moving-said cutting tool means in said x, y, and ? directions, computer control means for automatically controlling the operation of said x, y, and ? motors for moving said cutting tool means to cut a desired, preprogrammed pattern from said sheet, guide means for guiding movement of said metal sheet into said pattern cutting position, clamping means for securely holding said metal sheet stationary at said pattern cutting position during pattern cutting thereof, and motor means associated with said cutting tool means for moving said blades with respect to each other to shear said metal sheet during pattern cutting thereof.

2. Apparatus as recited in claim 1 wherein said conveying means comprises at least one conveyor belt, and wherein said supporting means associated with said conveying means comprises a plurality of spaced tips of flexible ma-terial attached to and extending upwardly from said conveyor belt, the top of each tip being spaced from said conveyor belt a distance sufficient to allow receipt of the lower blade of said cutting tool means between said metal sheet and said conveyor belt without damage to said conveyor belt.

3. Apparatus as recited in claim 2 wherein said conveying means comprises a pair of conveyor belts that are relatively movable with respect to each other in a direction transverse of the direction of feed of sheet metal to said apparatus.

4. Apparatus as recited in claim 3 wherein means are provided for moving said conveyor belts with respect to each other, said means comprising a pair of wheeled carriages mounting one of said conveyor belts adjacent one end thereof, a pair of screw-threaded rods, each receivable by a portion of one of said wheeled carriages to transform rotational movement of said rod to linear movement of said wheeled carriage in said direction transverse to the feed direction of said sheet metal, and means for simultaneously rotating each of said screw rods.

5. Apparatus as recited in claim 1 further com-prising a notching assembly disposed on either side of a metal sheet received by said apparatus, each notching assembly en-gaging a side edge of said metal sheet for notching of the edge at predetermined positions as determined by said com-puter means.

6. Apparatus as recited in claim 5 further comprising first means for mounting each notching assembly for longitudinal movement in a first path along the length of a metal sheet received by said apparatus, and notcher motor means controlled by said computer means for moving said notching assembly in said first path of movement.

7. Apparatus as recited in claim 6 wherein said notching assembly includes a notching piston, a plurality of notching dies, and an indexer for moving a selected one of said plurality of notching dies into operative position under said notching piston, operation of said piston causing depression of said selected die to penetrate the edge of said metal sheet and form a notch of a given shape therein,

8. Apparatus as recited in claim 6 further com-prising second means for mounting one of said notching assemblies and said first mounting means thereof for linear movement in a second path in a direction transverse to the direction of movement of said notching assembly in said first path, said one notching assembly and first mounting means being movable in said second path to accommodate metal sheets or different width that might be fed to said apparatus.

9. Apparatus as recited in claim 8 wherein said second mounting means comprises a pair of screw-rods, one passing through an end member at each end of said first mounting means, each end member having a screw-threaded portion thereof for converting rotational movement of a screw-rod into linear movement of said end means, and means for rotating said screw-rods simultaneously.

10, Apparatus as recited in claim 8 wherein said guide means comprise a plurality of guide rollers arranged along the first path of movement of each of said notching assemblies and some of said guide rollers mounted for move-ment with said one notching assembly in said second path, and means for mounting said guide rollers for movement out of the path of movement of said notching assemblies during movement thereof in said first path of movement.

11. Apparatus as recited in claim 1 wherein said guide means comprises plurality of rollers arranged on either side of a metal sheet received by said apparatus, each of said rollers having a groove formed therein for receipt of said metal sheet therein to provide some vertical support as well as horizontal guiding for said metal sheet.

12. Apparatus as recited in claim 1 wherein said clamping means comprises an abutment member mounted for abutment by the leading edge of said metal sheet as it is fed to said apparatus, said abutment member having a top surface thereof, and a piston mounted below said metal sheet received by said abutment surface for engaging the sheet bottom and forcing the sheet into secure clamping engagement with said top surface of said abutment member.

13. Apparatus as recited in claim 12 wherein said clamping means further comprises a cylinder for movement of said piston to and from clamping engagement with said sheet, and means for mounting said abutment member for pivotal move-ment about a horizontal axis out of interfering relationship with said metal sheet to allow movement of said metal sheet out of said apparatus in said feed direction after pattern cutting thereof has been completed.

14. Apparatus as recited in claim 12 further com-prising a microswitch or the like mounted on said abutment member and responsive to the engagement of said metal sheet with said abutment member, said microswitch operating a cylinder for moving said piston member to clamping engagement with said sheet and substantially simultaneously stopping operation of said conveying means.

15. Apparatus as recited in claim 12 wherein said clamping means further comprises a squaring pin for engaging the back edge of said sheet when in pattern cutting position to assist said abutment member, said guide means, and said conveyor supporting means in holding said metal sheet in proper pattern cutting position, said squaring pin including means for moving said squaring pin in the direction of feed of said metal sheet into said apparatus for accommodating sheets of different length.

16. Apparatus as recited in claim 15 wherein said mounting means for said squaring pin includes a screw-rod elongated in the feed direction of said metal sheet, and a supporting member receiving said screw-rod for trans-forming rotational movement of said screw-rod into linear movement of said squaring pin, and means for rotating said screw-rod to move said squaring pin in said metal sheet feed direction or opposite to said direction.

17. Apparatus as recited in claim 16 wherein said squaring pin is mounted for pivotal movement in one direction so that a metal sheet being fed into said apparatus pivots it out of its way, but so that it securely abuts the back edge of the metal sheet to be held thereby once moved into abut-ting engagement therewith.

18, Apparatus as recited in claim 1 wherein said scissors cutting tool means further comprises an arm for mounting the lower of said cutting tool blades and a ball bearing mounted on said arm adjacent the trailing portion of said lower blade, said ball bearing for engaging the bottom surface of said metal sheet to allow for more accurate ? turning of said cutting tool.

19. Apparatus as recited in claim 18 wherein said arm is a lever pivotal about a horizontal axis, and wherein said ball bearing is disposed on the opposite side of said pivot as said lower blade member.

20. Apparatus as recited in claim 18 wherein said motor means associated with said cutting tool moves said upper blade linearly in a vertical direction to co-operate with said lower blade to effect shearing of said metal sheet,

21. Apparatus as recited in claim 20 wherein said lower blade is also movable by said cutting means.
motor to effect shearing of said metal sheet.

22. Apparatus as recited in claim 1 wherein said means for supporting said cutting tool means. for a movement about a vertical axis comprises a housing securely mounted to said means for supporting said cut-ting tool means above said conveying means, and a ver-tical shaft mounted in bearings of said housing for ro-tational movement with respect to said housing, said blades of said cutting tool means being connected to said shaft below said housing.

23. Apparatus as recited in claim 22 further comprising a gear mounted to the top of said vertical shaft, and a worm gear in engagement with said gear and operatively connected to said ? motor for rotation by said ? motor to in turn rotate said vertical shaft,

24. Apparatus as recited in claim 1 wherein said means for supporting said cutting tool means above said conveying means for movement in x and y horizontal directions includes two pair of frame members, one at each of four terminal corners of said apparatus, individual members of each of said pair being connected by a guide rod and at least one of said pairs also being connected by a first screw-rod, a pair of end members, one mounted for movement-along each of said guide rods connecting said frame members, at least one of said end members having a screw-threaded portion thereof for receipt of said first screw rod to transform rotational movement of said first screw-rod into longitudinal movement of said end members, a guide rod connecting said end members, a second screw rod extending between said end members, and a support for said cutting means, said support receiving said guide rod and having a screw-threaded portion thereof for receipt of said second screw-rod and for transforming rotational move-ment of said second screw-rod into linear movement of said support member, said y motor being connected to said first screw-rod for rotation thereof, and said x motor being con-nected to said second screw-rod for rotation thereof,

25. Apparatus as recited in claim 1 further comprising a roller rotatable about a horizontal axis dis-posed past the end of said conveying means in the feed di-rection of said metal sheet, said roller for receiving said metal sheet thereon after pattern cutting of said metal sheet.

26. Apparatus as recited in claim 25 further comprising a waste bin disposed substantially below said roller and for receipt of waste portions cut from said metal sheet as the pattern cut from said sheet is held in engagement with said roller-to prevent dropping thereof into said waste bin.

27. Apparatus as recited in Claim 1, wherein said guide means includes a hinged plate mounted on each side of said metal sheet, and means for moving said hinged plate from a first position wherein it is disposed in a substantially horizontal plane and guides movement of said metal sheet into cutting position, to a second position wherein it is in a generally vertical plane and does not perform a guiding function.

28. Apparatus as recited in Claim 1, further comprising a radius wheel or the like, and counter or the like associated therewith, said wheel and counter mounted on said cutting means for measuring the length of arcs and lines cut thereby, said counter being operatively connected to said computer control means for adjusting the control functions thereof in response to variations in arc and line lengths cut by said cutting means.

29. Apparatus as recited in Claim 1, further comprising a notching assembly disposed on either side of a metal sheet received by said apparatus, each notching assembly engaging a side edge of said metal sheet for notching of the edge at predetermined positions as deter-mined by said computer means.

30. A method of cutting a pattern from a hori-zontally disposed metal sheet comprising the steps of transporting in a feed direction the metal sheet on conveying means into a pattern cutting position, guiding the sheet into said position, stopping movement of said conveying means when said metal sheet reaches said pattern cutting position, automatically clamping said metal sheet at said pattern cutting position so that movement thereof is positively prevented, automatically cutting a pattern from said metal sheet with a computer controlled cutting means that is movable to any x-y coordinate of said sheet and any angular position, a, with respect to said sheet, said pattern cutting not damaging said conveying means, releasing clamping engagement of said sheet at said pattern cutting position while restarting said conveying means, and automatically conveying said pattern cut metal sheet away from said pattern cutting position in said feed direction.

31. A method as recited in Claim 30, comprising the further step of automatically separating the waste material from said pattern of said metal sheet as it is conveyed away from said pattern cutting position.

32. A method as recited in Claim 30, wherein said step of cutting a pattern from said metal sheet is ac-complished by shearing of said sheet, one cutting means blade being disposed below said sheet and another cutting means blade being disposed above said sheet.

33. A method as recited in Claim 30, comprising the further step of automatically forming notches in side edges of said metal sheet during pattern cutting thereof.