US1919287A

US1919287A - Apparatus for forming sheet metal forms

Info

Publication number: US1919287A
Application number: US577467A
Authority: US
Inventors: Auble James Lawrence
Original assignee: M & A Inc
Current assignee: M & A Inc
Priority date: 1931-11-27
Filing date: 1931-11-27
Publication date: 1933-07-25
Anticipated expiration: 1950-07-25

Description

July 25, 1933- J. L. AUBLE 1,919,287

APPARATUS FOR FORMI-NG SHEET METAL FORMS Filed Nov. ,27, 1931 5 Sheets-Sheevt l July 25, 1933.

J'. L. AUBLE APPARATUS FOR FORMING SHEET METAL FORMS Filed Nov. 27

5 Sheets-Sheet 2 July 25 1933 J. L.. AUBLE APPARATUS FOR FORMING SHEET METAL FORMS Filed Nov. 27, 1951v Y 5 sheets-sheet 5 7 38 j 3Q sa 37 l 8 015: 5 ,lll-L- la. 5 K n,

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July 25, L4 AUBLE APPARATUS FOR FORMING SHEET METAL FORMS Filed Nov. 27, 1931 5 Sheets-Sheet 4 B/LWMMMM ATTORNEYS.

July 25, 1933. 1 L AUBLE 1,919,287

APPARATUS FOR FORMING SHEET METAL FORMS 4 a 4 d 4/5 INVEN OR. j! .162. Z

ATTORNEYS.

ILO

' ment of my invention.

Patented July 25, 1.933

i UNITED STATES PATENT oI-"I-IC15.'N 7 l JAMES' LAWRENCE AUBLE, CFCINCIINNATI, oiio, `AssICfNon, To M. a A. fine., 0F

CINCINNATI, o1-11o,A CORPORATION or omo v I `APPARATUS ron ron-MING SHEET METALFORMS application med Noveiber 27, 1931.` serial No. 577,467;

My invention relates to 'theiartot drawingV and forming sheet metal into forms'bya series of forming operations wit-hout removing the'piece being formed Yfrom the drawing andfor'ming means. I Y

It is an object of my invention to provide a drawing and forming device for forming sheet metal into various forms by'continued movement in one direction whilethe various parts constituting the forming device autofmatically adjust themselves in proper rela# tion to the movements necessary to complete theforming operation.

Another object of my invention is to have afforming device of telescoping parts rotatable relative one to the other, and which adjust themselves automatically in proper position while the forming operation isin progress to completion.

` A further object is to provide a forming device lfor sheet metal forms having telescoping-rotative parts whichwill act in sequence and Vposition themselves so as to permit the formation of the objects formed in sequential operations 4without removing the piece from the forming device until it has been completely formed. n

Broadly itis the object of my invention to provide a plunger type drawing Land forming tool comprising a male' plunger with internal master shapes adapted to force metal discs into the rfemale partfof the forming means, elements within the female part comprising a plurality of rotatable telescoping members with helical guiding means to auto-V matically position t-he members in proper position for the various' steps essential in the forming operation, and thereby eliminate the necessity of removing the piece being formed from the device until the forming operation has been completed. n

' These and other objectswill be `more specifically pointed out in the specifications and the drawings forming part of this speciiica-` tion, `and villustrating a In the drawings Figure 1 is a side elevationwith partsfin section showing the device ready to receive a piece of sheetfmetal lfor forming.

preferred embodi- .provided in the bolsterblock.

portion `7b provides val shoulder '7C forvcontact Figure 2 is a perspective of a form to be made by the device. .l l

Figure 2a` is a side elevation of the device showing the lirst step of forming after shearing the metaldisc. i e Y y Figure 3 is an elevation in section showing another step in the forming operation.

A Figure 4 is a side lelevation with parts in section` showing theposition of the parts at' the completion of the formingl operation.

Figure '5 is a planin section taken on the line 5 5 of Figure 1*.i .Y

Fgu're 6 is a plan of one of the telescoping parts having internal helical guiding means. Figure 7 is an Velevation in section taken on the line'7lf7 of Figure 6'. Y

Figure 8 is atop plan of another telescoping member `to which is attached thetrip finger.. y, t y I y -Figure 9 is a side elevation ofthe member shownin Figure 8; i y,

,F'gure 10. isla front elevation of the cam operating the trip. f

` Figure l1 is asideelevationv with part in section of the cam operating the trip.

A. Figure 12 is a plan vviewof the blank holder. y

Figure 13 is a side elevation of the fblank holder.' f I Figures 14 to 17 inclusive are sectional Views showing the type of formiing device intended for use on a toggle press,v and the various Vpositions takenby the parts in the act of forming a metal shell.

Afmain bolster block 1 consists of a base la vand. an upwardly extending bosslb having a cavity 1C for retaining the parts of the forming device. The bottom 2 of the cavity has athreaded holef, 'vertical spring retaining `pockets 3a, an elongatedslot and hole 3b for a cam'rod 4, and otherholes 3C for piston rods 5L Fixed to the base of the bolster block is a downwardly extending boss 6 with an inner bore 6a to provide a hydraulic cylinder 6b for apistonc.v f U a v A lstationary centrally located forming i member 7 has a threaded portiona for securing it by screwing intothe threaded hole A cylindrical l with the bottom of the cavity in the bolster block. The surface 8 of the cylindricalstud portion provides a bearing for atelescoping member.l The forming part of this member in thisicase has a shape similar to a mushroom.k A shoulder c on the underside of the mushroom shape of this member acts a stop and limits the upward movement ofatelescoping member. A center hole Tf, the top of which pub-vides a shearing edge for a piercing die, extends r*through the full length of the stationary member. Blanks pierced in this hole allrthrough to a pocket 7g and are discharged through an openingh` provided in the bolster block.

While only two telescoping members have been illustrated, it will readily occur to those skilledin the art to decrease or increase the number" of telescoping members,r depending upon the contour of the `orm'required. In this case the inner telescoping member has a flange Qintegral with which is a trip linger {Qa'extending beyond the Vsurface 9b' of the frange. The base 9c of the telescoping member is slidable while rotating on the bottom of the cavity. Extending upwardly and inn tegral with the base is altube 10. VOn the f outer surface of the ltube are fixed sections 10a of aniultiple helix. The proper angle of the off the Vflange ofthe inner telescoping mem- Y 'co ber extends downwardly and is slidable in an annular groove 1122 in thebolster block. This Vpin is acted upon by a compression spring 11ev retained within ythe groove, and the spring in turn reacts against a {ixed abutment 11d shown as a pin also within the groove.

The other telescoping member has a sleeve 12 with a hole 12a on'the surface of which are extending' sections 1Q?) of multiple helixes. The angle of these lielixes will correspond tov the angle on the lirst described telescoping member, so that theykcan comeinto mesh and slide along leach other. This member is sl-idable vertically on the other telescopingmember. The'sleevehas two

dii'l'erent diameters

12d and 12e, the top edge 127e of the largest "of the two diameters. providing a shearing for excess material of thc'blmk.`V Inte- `gal with and at the bottom of the'sleeve is av flange13 in which are lixed downwardly extending plunger rods 13a. Thel rodshave heads 13b slidable in the spring pockets 3a and the heads rest on the springs 130, also connned within the pockets 3a. Other clear- Vledge 15g which acts as a stoptolimit This inner telescopingmember ance holes 13d are provided in the flange in which piston rods 5 are tree to slide. An

elongated clearanceslot lill is provided for theY Vcam rod 4.' This slot permits downward movement of the cam.

Y The blank Vholder is a ring la-witha hole 15?) so that it can slide down over the surface 12e Vof the telescopingmember 12. Fixed to the underside 15o of thev blank holder are spaced piston rods 5. One of these rods has an elongated notch 15d so that the trip finger 9a will not be: interfered with while being moved by the cam.

Theouter surface of the ring is provided with two different diameters 15e and 157e.

The diameter 15]e is slidable within a hole 16 of a 'blanking'die 'which vwill be later explained. Thefother diameter 15e providesl a t 1e upward movement of theI blank holder.v .As previously stated, the piston is rigidly secured to the piston rods at 15h.

A counterbore'l is provided in thefbolster l block for'securin'g therein a blanking die. 17

with a central opening 17a having a shearing edge 17?), A shoulder 17cbeneath the shearing edge is provided as stop means against which the ledge 15g comes in Contact to limit the upward'mo-vement of the blank holder.

The inner surface 17d of the hole providing the cutting edge acts as a guide for the blank holder and alsoas a punch. The die remains stationaryvat alltimes. *L f V The cam rod l has a hole 18 for spring 18a. A plug'lS) with a hole18c slidably retains a plunger shank 19 ywith a head 19a that compresses the spring whenever'theend 196.01? the plunger shank bea-rs onfthe piston.

The plug'is ixe'd in the hole in the end of the rodV and prevents the spring from ejecting the `plunger; The upper end 190 has a rectangular extension 20, one face 20a beingvertical and parallel to the central axis of the rod.Y A sloping surfaceQOb connects the vertical facer with the rod andactsas alcamY surfaceto rotate-the' inner telescopingmember by contact with the trip on this said inner telescoping member. l At the top ofthe'cam rod a tapped hole vis provided 'for an adjusting screw 21 having a lock nut 21ato hold it in a set position. The cam rod isslidably mounted inthe hole 3b inthe bolster block. Itis moved downwardly. by the blank holder and upwardly by the piston that actuates the blank holder. i

The plunger or male forming member when assembled is rigidly attached to the ram of a' suitable press not shown). It comprises va punch holder22fhaving a circular'hub 22a,

with a counterbore 22?) and a central hole 220. Integraly with the hub isl a` flangerv 23 also provided with a counterboreV which centrally locatesa combined punch and forming member which .will be later explained. ',Holes 24: are provided' for screws which Ysecure' the .im y

' are slidably 'retained'therein punch rand forming'member to the iange. Other holes are provided `for rods 26 that These rods are rigidly attached to a plate' 27 that is slidably mounted within the counterbore 225.' On

the upper side of the plateis a stud 27a that is rigidly attachedtothe plate. This stud comes into Contact with a part of the press ramand causes the plate with` itsrods to move downward and push on a stripper. s

The combination punch and forming member 28 is rigidly secured in the counterbore 29 by screws iu its flangey port-ion 28a. An extending boss 30v is cylindrical in shape andV yis free to slide in the hole inthe blank holder.

The bottom edge 30a is constructed to provide a shearing edge forblankspto be cutl from sheet material. The upper( end 30b'is counterbored to receive a 'plunger to bedescribed. Another hole 300 is provided as' a bearing `for the plunger and connect-'s the counter-bore with the lower end 30d of the plunger. Thelower end will be'machined to the outside contour of a particularform whiclnfin this case, is shown at 3l, and consists of concentric rings Sla'and 316, joined together by-a shoulder Blogand terminating in a cone-shaped top 31d. y I

The ej-ecting plunger 32 has a sleeve-like portion 32a slidably mounted in the hole 30C. Integral withvthe sleeve-like portion isa hub 32?) that is slidably mounted in (the counterbore inthe upper end of t-h'e'punch. In the" center of the plungerthere is a hole 32e' for slidably retaininga piercing punch 33. shoulder 32d limits the movement of the ejecting plunger when it comes intoA contact with the base fof the counterbore.v

' The piercing punch has a rshank afwhich is pressed and fixed within the hole 220 provided in the punch holder. The top end. 337) -of the shank abuts against a'sho'ulder 34 pro,-

vided in the hole 22e. Thelower end 330 of the shank is slidably mounted inthe. hole 300 in the ejecting plunger. The 'bottom end 33d is the piercing end of the punch.` i

A brake shoe 37 rigidly fastened to a rod 37a Ibears against the outer surface of the 'flange of the inner tele-scoping member. The rod' 37a is slidably mounted in a hole 38 in,

the boss of the bolster block. ThefendfSa is threaded lfor adjusting nuts-386 that bear against a compression springg39"slidablvA mounted onthe end of the rod. AfU-shaped band 40 is rigidlyattached to the boss of the Vbolster block and the inner side 40a. acts 'as 'an `abutment forfth'e spring which is always Vholdinr1 the brake shoe in contact with theA flange on the telescoping member. Y

An alternative type of forming tool which is intended for useon a toggle press 'will ,now be described. In this forming tool the operation and the part-s are inverted when compared with respect to the tool ust described. It consists of a bolster block 4ly havinga hol- 4The punch, asin" the first described Vin the opening 480.

low boss 41a and a `flange '416. Internally within the hollow boss ismounteda` female Adie block 42 having a central hole 42a'with `varyingdiameters`42b, 42e and 42d. The two `upper diameters terminatein beveledshoulders 43 and 43a. A top edge 43?) of the largest diameter provides la'shearin'g edge.

Lwill be attached to atoggle actuated lram of af toggle 'press1 (not shown).` Rigidlylatdevice,

tachedV tothe movable `part of theram 1s a plate 44 having a hole 44a therein. yOn the top t 44?),fixedly attached, is a beveled cam' member. 440. O-n the underside 44d. is fixed-'a flange .45'y integral with acylinder"45z extending from the flange.' -A tapped hole 456 for an. y lairinlet tube 45o is provided on the side of the cylinder. A disc piston 46 is slidably mounted within'the.l cylinder, and has a hole 46a that bearsandis slidable on the outersurface of one forming member to be explained; f

` The forming member y47 is rigidlyl fasf tened in the fiange 45. It has'a beveled edge 47av and fa central "hole 47?); This forming member performs the shearing of thedisc and the first step in the forming of'a shell, as

forms the: second step in thev forming opera`` tion. A vertical shaft 49 is slidablymounted a shoulder 495 against which a sleeve 50 rests.

This sleeve is xed on the shaft. On. the outer y "V""' surfacefandat the lower jend 50a there is a helix 506 which can mesh with -theotherhelix on thesecond forming member.

f Slidably mountedon the sleeve is a collarl,`

with an extending "finger 52 With'a sloping surface`52a. It is seated on thel top edgef52`b ofjthersecond forming member, as shown in Figure 14. This collar rotates the 'sleeve' by means of a key 54 Vfixed in the'sleeve'an'd `meshing in a slot 55 in the collar and brings the two helixes int-oposition so that'the sleeve and the secon d forming member can telescope upon eachother. y y Y y i i. Oplertz'oajof first forming tool Figure l shows the position of all parts at The upper end 49d of. .this shaft is smaller in diameter andiprovides the beginning ofthe forming operation and shown von top ofthe die. Thej'blank holder7 telescoping member and the cam are in the exa sheet of metal, indicated in dotted linesfis f Y treme upper positions. The teleseopingmem-` ber 12 isresting on the flattops of the'helixes -of the other telescoping member.y The punch aud plunger part of thelforming tool'move .continuously during the forming operation.

Etheblank holder pushes-'the cam roddown--` blank holder. While moving down,

v12 will slide down over the inner The firstv forming operation is accom-v plished -by forcing the metal downover the .top of the telescoping member 12 and up into thel largest diameter of the plunger (see Fig. 2a). While thisv operation isY taking place,

' l wai-d and the cam will Vrotate. the inner tele- 115 scoping member into position so that the lielixes on the-members can engage. tlie'heliXes engagethe telescoping member member. yThe inner telescoping member will rotate by the action of the continually applied"V pressure of tric plunger- While the member 12 is sliding fdown over .the inner itelescopin'g member, the metal will be forcedy Vdown over the top of-theAiXed forming member, asv shown in Figure 3.

The ejecting-plungerv will then come into.

contact with thetop ofthe form. and hold it for the piercing operation. Further move- Vment forces the metal up into Vthe female form and at the same time the excess material 36v will be sheared jotf around-.the,circle 36a,

Ybecause the plunger forces themetal over the shearing' edgelQf of the telescoping member .12. rlhe holeBGb-will also be pierced, and the parts will then be ink the position as .shown in Figure 4. 1

l'causes the piston' to rise. 40

The plunger will then return upward. Air is admitted to thehydraulicv ,cylinder and With the rising of thepiston the blankv holder moves towards its-'initial position. The Vcam is .also movedi up-by the piston.' Pressure having been taken oft' of the telescoping member 12, the springs 13,0 react and force it to its vuppermost position.

Y'11b will lalso react on the pin 11 and rotate the inner telescoping member until it will be inthe position with the telescoping member' 12 resting on the. flat tops of the h'elixes on the inner telescoping member. s Y

- The formv will risefwith the plunger, and

a fixed member on the press ram. The plate with its rods will pushon thev ejecting plunger, which in turn will then push on the lform vand eject it from'the plunger.v All parts will then be in position, as shown in Figure 1.-.

v,Opewrtz'o'a `0.7 toggvleiprcs'a forimagv 25002 vA sheet of'metal is laid on top of the die. NrThe punch is -moved 46 securely clamps'- A the die. A disc of first forming member and is then 'pushed'i'nto downward and the disc the-'metal to the top of metal is'sheared by the `and the sleeve so' When telescoping ,Simultaneously vthespring in the slot plunger. when 1t hasreached .a certain point in upward travel, the stud 27a will come in contact with the largest diameter of the idie, as shown -in .Figure 15.

The forming member 48 then pushesthe partly formed shell intov the next smaller diameter ofthe die, as shown in Figure 16. VVhen` the plunger reaches this i position','the fingerjwill have come in lcontact with the cam, vwhich will g rotate the-collar i *i that the helixes can mesh and allow the shaft to push theshell down It will be understood from the 'description that-the sleevev cannot godown into the forming. member until the collar has rotated the helixes into. position .for meshing.

Y y When the plunger returns upward the colilar will rotate the sleeve up out ofthe-form-` the top ofthe forming member.- Further upward movement brings the parts up out of the die, and` when the position as lshown in Figure 14.. n y Having thus described my invention, what I claim as new and desire to secure by Letters Patent,-is:V y y. .l .f .f-

1. In sheet forming apparatus comprising a forming die member and a rforming punch they .are out airis admitted" rinto the cylinder' and the disc will return-to farther intothe die, as shown'in igure17.

'-ing member/-wheieit will again seat itself on member, each having elements of successively decreasing cross dimensions, elements` of jone member successively coacting. with respective elements ofthe other member by relative recession of the elementsof l.one

`member incident to relative approachfof the members, and frictionally coacting means controlling the relative recession of the elements initially having a positive coaction -to prevent the relative recession,fmeans operated incident to relative approach of'the members, acting on the controlling means to initiate the Africtional coaction, said-control"- ling means being. operative independently of the initiating means after. initiation of its vfrictional coaction, and means to return-the elements and the initiating means to: their initial relative positions upon relative recession of said dieand punch members.-

. 2. Apparatus' as set forth in'v claim in.

which the means to return the elements com-- prises a spring,'and theI means to" return the initiating means comprises a Viiuid actuated C1515 ,3. Apparatus as set forth in claim 1 in y which the vrecession controllingmeans comprises an element rotatable relatively torone of. the receding element-s, said rotatable -elementand said receding element h aving mutually engaging helical portions thev friction between which, inconjunc'tion with the' friction of rotation of the rotatable element, provide the .control of recession of said receding element, and in which .the initiating"V means comprises an extension on said rotatableelement and a cam engaging'said extension.

4; Apparatus as set forth in claim 1 in which they recession-controlling means comprises an elementrotatable relatively to one i ofthe receding elements,'said rotatable element and saidreceding element having mutually engaging helical portions the friction between which, in conjunction with the friction of rotation ofthe rotatable element, provide'. `the control of recession of said receding ele-r which the returning means comprises aj spring acting upon said rotatable v.element substantially in the plane of its rotation.

prises an element. rotatable relatively `to one of the receding elements, said rotatable ele-4 ment and said receding element having mu tually engaging helical; portions the `friction between which, in conjunction lwith the fricf tion of rotation of the rotatable element, provide the control of reces'ssion of said receding element; and in which the :initiating means comprises an extension on said rotatable ele# ment and a cam engaging said extensiomand in which the returning means comprisesa spring actingv on thev receding element inV direction opposite to its recession.

6. Apparatus as set forth in claim llin which the recession controlling means comprises an element rotatable relatively to one Y of the receding elements, said rotatablevelement and said receding element having mutually engaging helical portions 4the friction between which, in conjunction with the friction of rotation of the rotatable element. providethe control of recession of said re-4 ceding eleinent, and'in which the initiating meansrcomprises an extension on said rotatable element and a *camV engaging said extension, and in whichthe means returning v the rotatable element'and the receding element comprisesra spring, Vand the means to return the initiating means comprises al fluid actuated plunger acting on the cam. 7. Apparatus as set forthv in claim 1 i Vwhich the recession controlling means comprises an element rotatable relatively to `one of the recedingy elements, said rotatable element land said receding element having mutually engaging helical portions' the fric tion between which, in conjunction vwith the friction of rotation of the rotatable element,

provide the control of recession of said re-- ceding element, and in which the initiating means comprises an eirtensionon` said rotatable element and a cam engaging said eX- tension, and in which the means returningl the rotatable element and the receding element -comprises a spring acting on the rotatable element substantially ina plane of its rotation, and a second spring acting on the receding element in direction opposite to' its recession. e.

' 8. Apparatus'as set forthin claim l in end permitting thecam to mai which 'therecession controlling means com# prises an element rotatable relativelyvto. one

ofthereceding elements, said l rotatable ele- ,i

inent'and said receding element having mu?1 tually,l engaging helical portions the friction,

betweenjwhich,in conjunction with the fric"y in which the means returning the rotatable g elementy and the're'ceding element comprises" j 5. Apparatus asset forth lin claim 1in which the recession controlling meansfcom-Y a spring acting on therotatableele'ment sub stantiallyin a plane of itsfirotation, and a second spring acting on the'V receding element y in *directionl oppositev to its recession, 'and'in which thesmeans to -returiithe initiating ing on, the cam.

s 1.9; Apparatus as sa forth il claim yifin means comprises a fluid actuated plunger actwhich thev forming punch member has the relativelyreceding elements andis'surrouiidled by a blanking die,and the forming die member is eXteriorly formed as a blanking punch coacting with the blanking die prior to the first forming coaction, and including e a blank holderin the blanking die which re-` cedes in blank holding coaction. with the forming die and by its recession operates the initiating means to initiate the frictional cothe means that returns which the recession controlli-ng means com-V prises an element rotatable relatively to one: i*

ofthe receding elements, said rotatable elee ment and said receding element having mutually engaging helical portions the friction between which, inconjunction withthe y friction of rotation-of the rotatable element,

provide thefcontrol of recession of the recedingvelement,and including, a brake Viii frictional contact with said rotatable element,

means having a yielding pressure onL said `brake to holdit in said contact, and means for adjusting said pressure. Y*

11. rApparatus as setforth in claimjl in which the initiating meanscomprises a' cam having :means for adjusting` its effective length and operating Ameans advanced Ain-v cident to relative approach of the members,

engaging one end of the cam,and in which its advanced positiomsaidcamhaving its opvthe means for` Vreturning the initiating means f comprises a fluid-actuated plungerconnected to` andv returningsaid operating means from posite end yielding and engaged Vby saidl JlunfrerV for return of the 'cam C! said yielding. y ntain contact with the plunger and said operating means vat various adjustnientsof itsvedvectyive length.

`121Insheet forming apparatus, a k'fixed centralforming punch element, an elementl rotat-able around said punch, -a forming,y

ierivr Y the punch eleinents, and means punch l element. surrounding ancl` Vadapted A recede relative toSaicl central punch'element and rotatable' element, saicl surrounding punch element andv said vrotatableV element having `-mutually.engaging helical portions controlling recessionV of' :the forming velement by rotation of the rotatable eleinentfand inif- Y tially inunniesheol engagement, positively preventing" vrecession of said forming kelement, a forming veo die having interior elements to coact, respectively, Withs'aiclfcentral' punch element and with sailjsurrountling punch ele- Y saicl rotatable element4 flSfAppai-atus' as set forth iny claim 12 lin Whichjthe surrounding punch element initially'extends past the central punch element to `coact with itsy respective die element previousto' coaction of the centralfpunch element With its', respective` die element.

'and the forming Volie 1s eX;

a blankinig' die,

as a blanking punch coacting triorlyformed With the ing coactlion, and including a vblank holder intheblanking die whichr recedes in blank holding coaction `Withtheforrning die and constitutes'a transmission element by means n forth in 'claim 1.2 in which the punchelements are surroundedrby blanking die prior to thefrst form Y of which the'forining die actuates the cani v means, and theV initially extending past the central punch ele` inent' to effect the' lirst forming coaction, previous to coacti'onlof the central punchelement with its respectivedie element. f f

-z JAMESLAWRENGEAUBLE. Y

surrounding punchelement n v