CA1311438C - System for transferring workpieces through a series of work stations - Google Patents

Abstract

Abstract of the Disclosure A system for transferring workpieces through a series of linearly aligned, equally spaced work stations where a predetermined sequence of operations are performed thereon. The workpieces are transferred along an X axis by a plurality of workpiece gripping finger operators mounted on a transfer rail at equally spaced locations thereon corresponding to the spacing of the work stations. The transfer rail is reciprocated along the X axis for a distance equal to the spacing between adjacent work stations. Independently supported actuator units are provided which have a lateral arm to support the transfer rail and to impart up and down and back and forth movement to it. The means for moving the workpiece in all three axes are individually controllable and may be coordinated with operation of, for example, a transfer press.

Description

~ 1 31 1 438 Thl# imrentiol- relates generE~lly to produc~lon ~y~tem~
w~arein workpieces are ~ran ferre~ through a serles of equally ~;pa::ed, l~ne;~-ly alic~ned work l;tations whicll perform ~ predete~-mi ned sequence ~,f operations or~ the woxkpleces and, more pal^tlcularly, to ~iuch a ~iystem for ~u'cc)m~tia~lly ~rans~ferring the work~iec:es from one work ~5 s~atlon to an a~ acent work ~tat:ion within the ~ystem .

.. A~ltomated and p~rtly automated sy~em~ which aworXpiece i~ conv~yed t~rough a series ~,f w4rk stations ~0 wh~ch eas~:h perform one o~ a ~R~-ie~ of operat:lons on tlle workpiece have rapidly ~come the ~orm in manufacturing ~nd~ tr~e~ ~:uoh as ~he me~cal working indu~;try. ~1~
manu~ctu~ing oper~tions ~uch ~ metal stalnpin~, many E~eparate s~amping ~pera~lon~; may ~e required to rorm 1:h~
flat she~:t o metal into an article such a~:, for exampl~
a vehlcle hubcap. ~atller than u'~ 1ng several ~3eparate pres~e~ to stamp the part, it has ~ecome the indu~y -- 2 -- 1 31 1 ~38 standard to u~illzc a tr~nsfer feod prcss, a singl~ stroko of whloh i~ used to per~orm multiple ~ampin~ operations at ~ plurality of work Gtat1oll~, Typ1cally, a pair o~ matchin~
di~s are dlspoGed above and below each work ~tation. At each stroke of the pre~, a workpiece wlll ~e ~tamped betw2en each p~lr of ~e As a~ lndlv;.dual workplec~ move~
th~-ough ths ~erie6 of work s~a~ion~, it will be successively qtAmped ~y each paiL- of dle~ ~o Eorm the finlsh~d produc~
Obt~lou~;ly, for efficiell~ operal:ivn o ~u~ll a transf~r press, i~ i~ critically impor~ant tl~a~ a ~u~c~ssion of wor~pleces b~ imultan~ously tran~f~rred from one work ~ta~lon to the.next between each stroke of the pre~.
Furthermore, it is of~en nece~sary to realiyn the workpisce wl~h the various ~1e s~atlDns o~ the tranG~er pre6s. For example, the workplece may hav~ to be moved linearly ln c~the~- horizontal ~irection, or it ~ay be necessary ~0 rotat~ it. ~ypl~ally, lt i6 nece~ry ~o reorien~ ~h~
workpie~ a number o times be~ore ~or~ g o~ the pi~ce i~
~ini~hed. It i~ readlly apparent ~ha-t ~ome mean6 o~ rapidly and ~cc~rately performing mul~ipl~ ~r~n~f~rs and repositionings mu t be provided.
One system ~or performiny re~etitive ~ork~ c~
~rAnsfe~ ~nd multlpl~ realignment i~ a ~ype o~ walklng-beam sy~tem which pL-ovide~ tr~n~fer r~ x~ondlng alvng ~oth ~ides of a linear axl ~x ~xi~) th~ough the work -~ 3 ~~ l 31143~

~ation~ upon whLch the workplece~ ride between each ad~acen~ ~ork ~tati~n, Di6poscd on thc tran~er rail~ arc finy~r gxipper~ for g~ipping the workpieces. In th1s type o~ ~ystem, each o~ the rails 16 de6iglled rOr movement along S bo~h the X and the vertical ax~ (Z axi~ is, l~ bo~n r~ises and lower; the w~Jrkplece an~ mov~s it: 1 inearly from one work station to ~notl~r. ~u~t}~rmor~, t~le fing~r grippers h~ve ~so~ia~d actuator~ which pern~it them to move laterally (along the Y axl~, towa~d ~nd away Ll~om ~lle Workpiece~ ~or engagement therewi~h and di6engagement there~xom. Tl~us, thls design permit~ th~ ringer g~ippe~
to first enyage ~lle workpiece by operation o~ its ac~uator, the~ raise the workpiece to the tral-ser 1evel by a~tuation o~ th~ trAnsfer rAils, linearly move the wor~pi~e to the . 15 next wo~k station by urtller ~ctuation of the transfer rails, lowsr the workpiece, and finally ~isell~age frolil t2~e workpiece by retra~-1ng the ~inger gr1ppeL-s thererl~om 90 that ~he pre~s mAy be operated.
Although such tran~fer sy6~en~s are 1n wlde u~e, ~hr~y presont m~ny di~adv~n~ges. For example, many small~r ~tampl~g manu~acturr~rs and ~lleet me~al ~i~ bullders do not h~ve trans~er presses, which repre~en~ a s~lbstantial ~nve~tment, but have a need to dupli~a~e t2l~ act1On o~ a ~r~n~e~ p~e~ for d.le tryout purposes or short pl~oduo~lon 2 5 run~ .

131 1~38 Beoause a t3t~ndard trans~r pr~s~ supports the rAlls . - at eac~h end of ~t~e x-~xis, ~ther th2~n in the middle, the r~ are typically very heavy, and have a cross sec~tion designed to mlnimi~e 6ay. Moving t2le ma~ of l~ e~e r2~
~t produc'cion speecl~; rec~uire~; larg~ gea~s al~d cams, and a ma~ive fr~mework ~o suppor~ th~ mech~nlsm ~nd prov1 d~
~blli~y the~ eto.
Further~nore, standard tral~sf`er pre~ses ty~ic~lly l~ave tandardized rail po~ltlon~ and permi~ only two or three ~i~ferellt 6paaing~ ween the rail~; in the lifted position.
S~ndard transfer pre~;ses al~o ~lav~ on~ y a llmited number o~ ~;e~ing~ alon~ tl~e x-axi:~ an~ no adjustment of distance o~ travel ~n e-kher the up-down or back-~ortl~ direction~O
To exacerbate this pro~lem, the standardized settings are p~cull~r to ~Qach manufacturer an~ nol: t:andardlzed industry wi de. Henc~ would l~e vlrtually lmp~ lble for one shop ~o have trnnsfer prPs~;es capa~le of te~3tlng or running the many possible comblnation~; o~ available c~ ngs from variou~ press manu~Acturer6~
A ftlrther proble~n witll ~tandard transfe~ presse6 i5 the lack o~ pl-o~rls:Lon for ~asy renloval of th~ rails for acces3 ~or purpo~e~s o~ changlng ~che dies. The tran~rer rail:3 must he long~r than the distanc:e 13etw~en the aolumns ~P th~ p~e99 ~inca they ~lso ~r~a to load the workpiece into tl~e press and unload it there~rom. Th~re~ore, 131 1~3~

elaborate coupllng mechanl~m~ are neoca~ary ~ al~ow r~movAl of a portL~n o~ the rail wh~n ~h~ ~ooling 1~ ~emove~, Dle change c~pabllit~ ~, tl~erefore, an expen~ive option and permlt~ r~ll change or removal only with great dtf~lculty.
A3 a partial 601ution to ~ome o the~ problems, U.S.
Paten~ 4,621,526 to Scllafer e~ al di6clvses a 5yct~ wher~
tl~e tran~r rail doe~ not travel in ~e linear ~lrection from one ~t~ion to another. Rather, ~ secondary rall i~
mounted thereon and the f ~nyer unl~ are in turn mounted ol~
o the secondary rall. The secondary ra~ deQl~ned ~or reclproc~l movemellt along 'c~e x axls between ad~ acent wor~c ~p~ae~. This moYement ~s ac~ua~ed by ~ servomotor ~upported on the 6econdary rail. T~le ~ing~r unlts ~hem~elve~ are de6igned for lateral ll~oveme~t tow~d and away ~rom the worl~piece and are ~ctu~te~ by add~tlonal ~ervomotor~. In order to r~e ~nd lower the workpiecesJ l.ift columlls ar~
pro~ided upon whlch the tran~fer rall ls moullte~. The~e li~t columns ~L-e also ~ctua~ed by electrle servomotor~.
Hence, ~ccording to ~ch~el-'s de~i~n, only tlle ~ervomotors whlch c~use la~aral m~vemen-t o~ the rl~lger uni~s ~re actually carried along ~he fie~ndary rails, thus reduciny the size of ~he r~il6, ~i~pli~ying the sy~te~ and maklng it lesg p~o~ to failure. Le~ o th~ mechani~m i6 actually dispo~ed within ~he press, ~hu~ p-ovldin~ ~ less o~true~
o~er~tion thereo~. However ~ven wlth Schafer'~

-- 6 -~ 1 3~ 1 438 improvemen~3, mu~h of tho mechanism iE~ 111 dl~po~ed )n the trar~sf~r ~a~ 1~ . Furth~rmore, exi~ ing ~y~em~ oannot l)e modi~led tv add these lmp~ov ements .
It woul~ b~ ~e~ira~le to provide transfer rail~ which are support:e~l ln 1:h~ cent:~r to allow a muc~h smalleL^ L-ail ~L-os~ se~tion an~ perml~ ~he ~rans~er ~ystem to be buil~ to ~ny 1~3ng'ch. Sucl~ a modular ~y~;tem would pro~ ide the ~apa~ility of buil~lng longer transfer ~y~t~m than i8 pre~3en~ly poE~Elible.
It woul~ also be desiL-~ble to provide ~ more flexible tra~ er ~ys~m permi~ g a mul~iplicity of ~-ail posi~ions a~d ad~us~ment vr ~inger unl~ travel in each of t:he th~-ee directlon~ o~ -travel.
Furthe.r~ lt would ~3 de~ able to provlde ~n impro~t~d, 1~ econon~ical system wherel~y tlle finger unit~3 may l~e di~po6ed on the railfi ill relatioll to ~he workl~iece dul-ing die bu~ lding and tryout., whell a trans~er press ~ ~ typlcally not a~a~ lable. Such a syfitem sllould also allow grea~e~
~cce~:ihillt~y 1~o the dle~3 durlng ma~ntenarlce and repair ~y ~0 c~on~ainltlg the a~tua,to~ system ~or the transfer mechanism in s~parate module~ w}lic~ may k)e ~emove~, leavlng the rail~
in ~l-ope~- position in relatiol~ to th~ work~?iec~.
It ~ould al~so be desirable to p~-ovid~ a ~3y~t~em wh:l ch can be used i.n a clie ~ op t~ 61~nul~t;e the actlon of any 2s tr~n~;~er pre~;s tn c;rd~r to check or pL-O~ clearances o~

~ 7 _ 131 14~

moving parts of the dies in relation to the path of travel of the transfer rail, finger units and workpieces without the necessity of actually setting the dies in a tr~nsfer press.
It would be highly advantageous to devise a modular system wherein modules may be manu~actured in a limited number of sizes and can be used with presses of a variety of sizes and of various configurations, regardless of the direction of feed or of the press design.
The present invention provides a modular system particularly useful for transferring workpieces along a series of equally spaced, aligned work stations. While the preferred embodiment of the invention is used with a transfer feed press, the system is useful for transferring workpieces in any system having a series of equally spaced work stations aligned linearly along an axis whereon a predetermined sequence of operations is performed on the work pieces.
According to one aspect of the invention, there is provided for use in conjunction with an article forming press which includes a ram having an upper die associated therewit,h adapted to be driven along a path of travel in a Z-axis and engageable with a lower die supported by a bolster for forming a workpiece inserted therebetween, a transfer system for transferring workpieces between work stations aligned linearly along a central X-axis perpendicular to the Z-axis, to perform a predetermined sequence of operations on the workpieces, said system comprising a transfer rail extending longitudinally in spaced and parallel relation to the X axis and having a finger operator rail mounted thereupon for movement with respect thereto in a direction parallel to the x-axis, said finger operator rail being mounted enti.rely between said transfer rail and said central X-axis; a plurality of workpiece gripping finger operators mounted on the ~inger operator rail at equally spaced locations thereon corresponding to the spacing of the workstations, said finger operators extending laterally inboard from the transfer rail in a Y-axis, perpendicular to and toward the central X-axis and Z-axis and each terminating in a free end having a workpiece engaging section adapted to engage the workpieces and transfer them between adjacent workstations; and at least one actuator unit supported independently from the transfer rail and disposed at a location displaced laterally along the Y-axis from the article forming press, said actuator unit having a transfer carriage which extends therefrom in the Y-direction and which is operative to move the transfer rail along both the Y and Z
axis; drive means for said finger operator rail supported independently of and associated to move with said transfer rail; wherein said drive means and said actuator unit are powered by motor means which remains stationar~ with respect to the movement of said finger operator and transfer rails.
According to another aspect of the invention, there is provided a transfer press automation system for transferring workpieces along a series of equally spaced, aligned workstations at a central axis of a transfer feed press having a ram associated therewith, said system comprising a transfer rail extending along and in spaced relati.on to the central X-axis and extending longitudinally along a side of said workstation; an individually controllable finger operator rail mounted on an inboard side of said transfer rail for B

reciprocal movement with respect thereto Eor a distance equal to the spacing between adjacent workstations and in a direction corresponding to the X-axis and defining the direction of workpiece movement through the workstations, said finger operator rail being mounted entirely between said transfer rail and said central axis; linear drive means associated with said transfer rail and its associated figure rail, said linear drive means operative to effect the movement of the finger rail; a plurality of workpiece-engaging fingers supported on the finger rail at equally spaced locations thereon corresponding to the spacing of the series of work stations, each of said fingers extending laterally away from the transfer rail along the Y-axis perpendicular to and toward the X-axis and terminating in a free end having a workpiece engaging mechanism mounted thereon adapted to engage the workpieces; and an actuator unit associated with the transfer rail and disposed along the Y-axis and on a side of the transfer rail opposite the series of workstations, said actuator unit adapted to support the associated transfer rail and impart reciprocal motion thereto i.n directions corresponding to both the Y-axis and a Z-axis which is perpendicular to the ~ and Y axes and defining, respectively, the direction of finger operator movement into and out of engagement with the workpieces and the movement of the finger operators for raising and lowering the workpieces; where said actuator unit and said linear drive means are powered by motor means which are mounted independently from and which remain stationary with respect to said finger operator and the transfer rails.

- 9a - ~ 4 3 ~

In the preferred embodiment a pair of spac~d and parallel transfer rails extend longitudinally along both sides of the aligned work stations. Preferably, the pair of rails is side mounted in order to allow access to the press.
In one embodiment, the workpiece engaginy mechanism comprises horizontally extended fingers which are adapted to lift the workpiece from underneath. With the horizontall~
extending finger type of workpiece engaging mechanism which lifts the workpieces up, two parallel transfer rails and associated finger operator rails are provided which lift the workpieces on both sides. Such a system is suitable for transferring relatively large and heavy workpieces such as are commonly subject to stamping operations in a transfer press.
Individually controllable means are provided for imparting reciprocal linear motion to the finger operator rails along the direction of travel of the workpieces as they pass through the series of aligned work stations. The finger operator rail i9 slidably mounted on the transfer rail.
At least one actuator unit is disposed at a location displaced laterally from the transfer rail on a side thereof opposite the work stations. If a pair of transfer rails are provided, then at least one pair of actuators will be provided, with one disposed beside each transfer rail. Each actuator unit has a laterally extending arm or carriage which supports the transfer rail and is adapted to impart both lateral and up and down motion thereto. The lateral motion is along the Y axis in a direction corresponding to movement of the finger operators into and out of engagement with the workpieces. The up and down motion is along the Z axis and Bi 3 ~

corresponds to movement of the finger operators for raisin~
and lowering the workpieces.
In a preferred embodiment, the actua-tor unit comprises a dual axis hydraulic actuator operating the arm in the Y and z axes ~o engage and lift a workpiece, then lower and retract once the workpiece has been translated to the next work station by the finger operator rail. The hydraulic actuator comprises a pair of hydraulic fluid cylinders connected in parallel to a single fluid source driven by an independent motor. As the source outputs fluid, the arm will first be moved along the axis providing the least resistance until the arm reaches a stop. The arm then ~, ~ lo-- 1311~38 ~egin6 mo~ement nlony ~h~ ~e,cond axi~, since th~t axi~ then prov~de~ thQ le~6t r~sistAnce to movement. In this manner, ~he actuator unit autolllatically achiev~ ~equencing o~
driving forae~ wlthout the need for additlonAl timlng ~PE~ra~u~ .
In a preferred e.mbodlment, the actuator unlt and ltc ~otor are ~u~ported indepen~ently of and remaln~ ~tatlonary wlth respe~ ~o tlle nlotlon of the tr~nsfer rail. In anot~er embodiment, th~ actuator unl~ comprlse modular unit~ whi~h o may ea~lly be moved lnto and out of oper~ing relation~hip wlth ~he tran6f~r r~
The txan~fer ~ystem o~ the instant lnvention po~e~e6 the a~v~ntages of providlng Inovemen~ of th~ finger operators in all three dlrection~ necessary to e~feat transfer o~ the workpiece6 and realignmen~ thereo. In ~ontrast to prlor ar~ 6y6tems, none o~ the ~tu~or~ or motor6 whl~h provlde movemell~ in ~he three direo~lons are dispo~ed on the transfer or flnger operator r~ el~.
H~nce, the transfer rall Inay ~e made ~m~ller and llgh~or.
Fur~hermore, the a~tua~or unit6 aro lnd~pendently ~upp~r~cd ~rom the transfer ~11, resultiny ln ~n ef P~cient, modular ~y~tem.
Pr~eI~ably, the transfer ~y5~em further comprise~ at least one sensor means for ~tectlng the state of operation o~ the ~s~o~i~ted production ~y~tem or purpo~ o~

synchronlzing th~ oper~lon o~ the tran~fe~ m~hani~m to the 3ystem. In the C~9~ 0~ a ~rans~er pre6~, a s~nsor mean&
will be mounted on ~h~ press ~am ln order to sensc ~he position of ~he ram durlllg eaGh stroke o~ th~ pres~. ~he ~e~lsor i~; operatively connected t;o ~ meAn:~ ~or centr~lly controllill~ movement o the tr~n~fer rail and flnger ~perator rail to s~nohroniz~ travel of the workplece~
through ~he ~ucces~ive wor~ stations ln tlmed ~elation w1~h pe~fo~mance of the 3equence o~ oper~tions. Tl~ou~h th~
lo central control system, ~ larye number oP compl1~ated trans~er~ and multiple realignmen~s m~y be perfo~med in synchron~zed fas~.iol~ w1th the operation of the pre~ in a q~iGk, accurate and eff~c1ehk manner.
A llnear ac~ua~or for impart~ng recip~ocRl motion to ~h~ finger opera~or rail is associated to mo~ with, ~u~
~upported ~n~ep~ndelltly ~ro~ he transfer rail. A motor for powering the linear ~c~uator 16 ~uppor~ed lndependen~1y of the transf~r rail and remalns s~a~lonary Witll L-espeC~ to the ~ovement of th~ tran3feL- rail.
In th~ illu~trated ~mbodlment, tlle linear actuator i~
a ~elt drive ~y~em ~upported il~depelldently from the transfer rail and as30c~ated ~o move therewith an~ ~uppli~
~he reci~l~o~al mo~1on to tlle ~ln~er ol~erato~- rail. The ~elt drl~ ystem is powered by an lndependent motor whl~h -~ 12 -~ .

remaln~ 3~ationary durlng the operat.t~n o~ the tr~n~r and ~in~er ~p~rator rails.
The belt drive ~ys~em e~sen~.1Ally co~pri.6e~ a b~lt moun~ed with the tran~r ~all ~or recipa-ocal rot~tion in the directlon o~` travel o~ the workpieces. The bolt 1~
drlven ~y a t~ans~erse spline shaft whieh can move w1th ths lateral displaceme~ oX the ~-rnn~f~r r~l toward the ~or]c~tations. The ~ransverse 6plin~ shaft i~ drive~ by a vertl~al spline ~ha~t ~ar~sed ~or v~rtical mo~m~nt w.~th ~h~
~ran~er rail when a wo~kpiece ~s ll~ted. The vertical spllne sh~t i~ powered by ~n ind~pend~nt motor whl~h re~ainq stationa~y Wlth respe~t to th~ tr~n~er ~nd Plnger op~rator rail~.
In one embodiment, th~ ac~uator unit6 and motors for the tran~er and ~ing~r opera~or rails ~r~ mowlted on th~
crown oP ~he transfer pr~ss i-tsel~ ~o pl-ovide unob3~ructed access ~o the d$~ ~nd work ~t~tions.
In the ~mbo~lment wherein a ~ran~er rail ~nd ~socia-ted ~inger opera~or rall ar~ provi~e~ on e~h ~ide o~ the ~ran~er press, each slde ls preferably mechanically indep~nden~ o~ tha othe~, bu~ elec~ronic~lly 3yn~hr~ni2~d to the press ram sensor. In ~}liG m~nner ~ bo~h o~ the trans~er rails an~ the finger opera~or rA11~ ~unc~ion in~ependen~ly but cooperatingly to ~ran~er workp~ece~
~5 be~ween work ~tatlons.

-- 13 ~ 1311~38 Th~ a~ovo de6arlbed and further ~oatur~ and ~dv~ntages of the herein ~nvention may best be under6tood by xe~erenc~ to the ~o110willg de~ailed ~escription and . . dxawing in which:
FIGURE 1 i~ a perEipective view o 'che tl^~n~r~er sy~tem o ~he ins~a~ vellt10ll insta11ed ill a tr~n~~r pre~6;
FI~URE 2 1s a per~pective view of the tran~er 6y~tem of FIGURE 1 shown apart ~rom the tr~n~fer pres ;
FIGURE 2a i~ ~ perG~eative vlew of a ~ing1~ tran6~er ~y&tem accordin~ to the p~e6ent inventlon;
FIGURE 2~ 1~ a par~ial se~t10ll p1~ll view of ~h~
~ran~fe~- ~y~tem of FIGUR~ 2a;
~IGURE 3 is a per~pect1~e ~iew o~ a ~otor and dr1ve bel~ sys~en~ a~soc~ated Wi~l a transfer system ~ccordill~ to ~h~ pr~sent lnven~;ion for r~clprocal ac:tuation o~ a f inyer opera~or rail;
FIGURES ~ and 5 ~re 6ectton views a10n~ 11nes 4~41 4A-4~ and 5-5 ln F~GUR~ ~b showlng de~a~1s o the connec~ion o~ a reclpro~al drl~o belt to a f lnger operator rall;
FIGU~E 6 1~ a ~ect~on ~iow ~long 1in8~ G-G showing detalls o~ a dual axlG 2~ydrau1ic actuator ac~or~iny to the present inventiont - 1 31 1 ~38 -- 14 ~-FIGURE~ 7 and 8 are nide views of tho ~otu~t~r o~
FIGURE 6 nhowing th~ motlc~n imp~r ed by the actuakor to e, tr~n~fe~ rail;
FIaURI~ 9 i6 ~ hema~lc: diagram o the motor and S hydraul ic actua~lng ~y6tem ~or the ac~uator o~ FIGU~E 6;
~IGURE lO ls a plan vl~w of tlle outer ~tru~ture of the hydra~l lc actuatin~ sy~tem o:f FIGURE 9;
FI~U~ a ~lde view of tlle mo~o~ rOr actua~ing th~ hydr~ulic act~a~ing system of FIGUR~ 9;
PIGVR~ 12 is A p~rti~l ~ection end view of opposed ~tuatox unit~ ~ccordlng to ~he pre~ellt invelltioll en~agi ~nd li~ing a wor}ipiece ~rom a tran~fer pxess ~ork ~ta~ion;
and ~IGURE 13 ~3 a per~;pectiYe view Or a trall~fer Syst;~
a~cording ~o ~he pre~ient inventivll adap~e~ to ~ moulll;ed ~rom the overheAd ~tn~onary crown of ~ pre~s.

lled De~cr1p~ion of the Pr0~erre~_~m~vc~
Throuyllout t~le ~ollowing detailed de~crip~lon, lik~
reference numerals . are u~e~ to refer to l:he Sarne element shown in multiple ~igure6 thereof.
Re~erring now to the drawing an~ 1n par~ioul~r to FI~URES l and 2~ there is ~hown a workpiece tran~er ~ystem gen~rally de~ign~ted ~s lo inst~lled in a t:r~n~fe~- press g~ner~lly designated as 12. Tran~fer pLe~s 12 has a ~-- 15 plurality of work stati ons 14 whereln ~ ~erie~ o~ ~tamplng Qpera~lon~ ar~ pQr~orm~d on ~ ~ucce~ on o~ worlcpiec~ w.
A ram 1~ qlupports a plural i~y of upper dle halves 2 Oa and eaah ~trc,};e o~ ram 16 caus;e~ the WoL-}cpieces W to be stamped between ~n upper die 20a and an associ~ed ls~we~ die 20b to form the workpieoe~3 w~ A~i i6 conv~ntlon~l, t:~le low~r ~les 20b ~re moun~ed on bol6ters 22 an~ l:h~ ~Ipl~er die~ 20~ are mounted on the ram 16. The upper s~AtionAry part of ~he trnr~sfer press 12 is re~e~re:l tv a~; ~21e or~wt~
Extanding longltud.il-ally in paxall~l an~ s~aced Lashlon ~long bo~h side~ o~ the plu~allty of wor~; stations 14 ~f ~ran~fe~ pre86 12 i~ ansfer system generally 6howll in ~I~URE 2. Whlle an op~c~3ed pair of` transfer E;ystems i6 str~ed ~ n 61ngle sys~:em a hOWI~ in FIGURE 2a may be used depending oll tlle ~ize or t;ype of workpieces beiny tran~ferred. Tr~nser ~ystem lo compris~:s ~ tra~rer rall 24 dl~posed lat~rally outboard o~ ~ork ~atlon 14 and dl~
20, runnlng essf~ntially parallel thsreto. Mounted oll eACII
o~ the p~i~ of? transfer r~ ; 24 16 a ~in~er operal:vr ra~ 1 26 la~eL-Ally inbo~d of tranEifer rail 24 ad~aGen~ worlc ~ca~lon~3 14. ~ounted in ~urn on th~ fin~er o~eratv~ rail~
2~i ~re ~ plurality o~ 1'inger~ 28 whic~ extend laterally tow~rd 'ch~ wor~;pleces W. Each o~ tlle plu~ali~y v fln~
~ term~nate~ in a workplcce engaging E~ection 30. In tile em3~odlment lllustra~ed, each c~ the workpie(::e engaging 1 31 1 ~3~

, .
~ection~ 30 providea a restlng place for a corner o each o~ the plurallty o~ ~or~pieoe~ w ~ they are ~uceessively transferred ~rom one adjacent work ~tation 14 to anothQr work ~t~tion 14. I~ is to be ~nderstood that the plurali~y o workpiece tran3fer mechani~m6 30 may t~ke ~ ~riety o ~the~ ~on~entional defiign~ an~ conflgurd~ton~ 3uch as, ~or example, ~Q~ping flng~r~.
The pl~rality of finger operators ~8 are equ~lly epaced longitudlnally along th~ ~ran~er rail 24. ~n the cns~ o~
lOthe workpieces W ahown ~n the ~ra~iny, ~lle ~ing~r opera~o.rs ~8 are arrayed in pair~ ~o tha~ the wor~plece tran6fer me~hanl~ms 30 may ~upport each corner o~ a workpiece W. Th~
spacing between adj~ent pair~ of ~inger operator~ 2a corresponds ~o th~ ~pa~in~ between a~ja~ent wor~ qtations.
Flnger ope~ator r~il 2G is slldably moun~ed on raaeway 25 o-f trans~er r~il 24 in order to permlt reclproc~l, llne~r mo~ion oE the ~inger ope~ator rall 2~ wi~h ~cape~ to tran~er rail 24 alonc3 the X~axi~, i. e . the d~reçtlon o~
travel o~ workpi~ces W down ~he line o~ worX ~ntion~ 14.
Suc~ reciprocal, linear movement o~ flnger operator rail ~6 is crea~ed by means of a bel~ 56 moun~ed wi~hin ~oualng 52 on tran~;fe~r rail 24 and powered by ~ belt dri~te ~y~tem gener~lly shown in FIGURE 3. When powered by 25appropriately con~rolled electrlcal current, the belt dr~v~

131 1~38 ~-- 17 --~

uy~t~m z~nd belt w~ 11 p~ovlde reciprocal lln~Rr motion of r~il 26 wlth re~p~t 'cs) rail 2~.
~he lin~ar r~alprooal movement o~ finger ~per~tor r~l 2~ along transf~r rail 24 cau~3~s the ~inger unlts 2~ al~o S to mov~ reciprocally in a llnear ùirection along ~he X axi~
el8 1E; 6hown by the ~rr~w in FIGURE 2. In ~der l:e oc~u~e the f~nger operat~rs 2~ ~o move ln the Z dlreo-tlon ~up an~l down1 ~nd in the Y direation (laterally, into and ou~ of ~ng~gement wltll th~ wo~kpiec:e W), at le~s~ on~ actuator unit 30 i~ prclvideù gene~ally ~l~owll at FI~lJX~ 6. Actuator unit 30 i~ upported lndependently o~ ~ransrer rail 24~ In the embodiment shown in ~I(;U~ES 1 and 2, actuator uni~ 3 0 is ~loor mounted hy means o~ a longltudinal support frame ~2 runnlng p~rallel alollg-~lde the t~ans~er pres~.
Actua'cor unlt 30 c:ould, alter~latively, bf~ mounted on or withln its own ~no~ular housing equlppe~, for example, wl~h roller~ or c:as~ers to p~m~ t the actuator uni-t t:o be ez~nily moved into and o~ o~ ope~ating relatlon~h~p wi'ch the t~-~n~r pres~.
Actuator unit 30 in~lude~ A la~erally extencling arm or t~n~e~ c~rriage 3~ which ext~nd~ toward th~ direcl~ tl oi~
the workploce ~nd which 6upports txaa~ fe~ rail 24. In the embod1ment ~hown in FIGURES 2a an~ 2h, a pair of ac~uator un~t~ 30 2~lnd a~i~o~iated ~ransfer ~arriages 34 are provided 2S in ord~r t:o ade~ua'cely suppor~ ~he t:ransfer ~ail 24~ It i~

-~ lB -- 1 3 1 1 438 contemplated tha~ ~t lens~ on~ ~ctuator Init ~n w~ll be needed for eacll transfe~ r~il 24, and typic~lly, at lea~t one pair of actuator ~nits 30 wlll be needed ~o ~upport each tr~n~fer rall 24~
~e~erring to FIGURES ~b and 3-5, tlle belt d~ive system ~nd belt drlve mo~or for causlng the reciproc~l 31~ding movement of finger operator rall 2~ alol-g ~he X-axl~ ~3 ~hown in detail. ~l'he belt drive ~ys~em ~ p~wcred by a reciproc~l rota~y motor 36 connected ~y bel~ 38 to ~ drive lo wheel 40 sl~dably engaging vertle~l spline ~h~ft 42.
Reaiprocal rotary motion given to spline ~ha~t 42 by motor 36 i~ tran~fer~ed via gear box 4A ~ ~elt 44 ~nd ~riv~ wheel~
48 to tran~ver3e spline shaf~ 50. ~ransver~e spline 6haft 50 is connected ~rough the wall ~f houslng 52 on tr~nB~er rail ~4 ~o a drive wheel 54 posl~ioned ~hereln n~ shown in FIGURE 5. Drlve wheel 54 l~a~ an unpow~red count0rpar~
long~tudinally ~pa~ed the~efrom in hou~ln~ 52 ~nd a dri~
belt 56 i~ moun~ed between the t~o wh~el~ can b~ ~een that reciprocal rotary mo~on ~f ~otor ~6 will be tr~nR~erred thro~gh the driv~ belt syqtem to the drive balt mounted in hou~iny 52 on tran3~er rall 24.
Referring now to FIGURES 4 and 4a, f lnger opcrato~ rail ~6 i~ ~hown slidably moun~ed la~erally inw~rd of tran~er rail ~4 along the Y-axi~ by way of ~e~ring block~ 5~ having a plurality of beaxing~ or rollers ~0 enyaging rRcew~y block 1 3 1 1 ~ 3 ~

25 mounted on ~ran~er rail 2~ sppor~ braoket arm 6~
fa~tened to a po~ti~ o~ drlve belt 56 by su~t~ble moun'c~ ng ~ru~ture ~4 extend3 over and ac.ross trAnsfer rall 2~ and xedly att~ched to finyer operator rail 26. t~hell drive belt ~ ls reciprocated wl~hin the l~ousin~, ~racket arm 62 conne~ted to the drive belt will rRcipro~a~ ~in~er operator rail 26 w1th respect ~o the treln~fer ~ail i.n th~ ~1re~tion o~ motion of the drive belt, i . e . alon~ tlle X-axis, hould be noted that -tl~e drive ~elt 6y~;tem motor ~pparaku~ compri~ing motor 3~, drlve wheel 40, an~ ~e].t ~
are ~uppor~ed on ~rfa~ 33 of lonyitudinal ~lp~ort 32 independently of and ~tationary w~ tes~e~t to ~l~e ~rall~f~r rail. Vertl~al ~pline sha~ ~2, g~ar box 44, be~.t and wheel~ 46 and 48 and tr~nsver~e ~l1n~ af~ 50 oompri~ing the drl~e b~lt sy~;~em ~re connected thL'OUg]l 8y8tem hou~;in~
49 to ~ carriage ~upport G~ o~ transer ~arL-lage 34 on A~uator 30 or movement tl~erewi~l~ along ~}~ 2-axl~.
Upon lateral inward extensioll alotlg the Y-~xis o tL~an~fe~ r~ 4~ trnnsver6e spline shaft 50 mounte~ to ~ e within upper drive wheel 48 an~ connected by ~lnk ~embly 51, connecte.d to the drive ~lt in llouslng 52 wll~
be pulled alony ther~with due t~ s sliding eng~gemen~ with upper g~ared wheel 48. When the tran~rer rail 1~ e~ by a~tua~or unit 30 along the Z-axl~, for example to lLft an eng~ed wor~plece ~rom ~ work Eitatloll, tlle drive ~elt Sy~

-~ 20 -- 1 31 1 438 will be li~ted therewith by ~.h~ ACtU~to~ unit a~ verti~l ~pline sha$t 42 ~lides throuyh driv~ wh~el 40.
When -the dr~v~ ~elt ~y~t~m has been tran~lated along both the Y ~nd Z axes wlth ~he tran~er rall, ~uch as when a wo~p~ece has been b~th engaged by the f lnger opera~or~
and li~ted rrOm ~ work ~a~ion, st~tion~ry dr~ve bel~ motor 3~ ls activated to re~l~rocate flnger opera~or rall 26 and ~he workplece along tlle X-a~i3 be~ween ad~cent wor~
statlons. The ~ndepend~n~ support and mounting of the driv~
balt motor and drive bel~ sy~am with re~pe~t to trans~er rail 24 and finger operator rail 26 g~e~ly reduce~ the weight supported ~hereby, permitting reduction in the 6i ze and weight of the ra~ls an~ accordlngly ~ higher ~ate of oper~t;on.
Referring now to FIGU~ES 6-9, 4n actuator unlt 30 for importing mo~ion ~long the Y an~ Z axes to th~ tr~n~er r~l i~ ~hown in ~ectlon. A ~ran6~er carriag~ 34 ~upport~ng trans~er rail 24 i~ slldably moullted along ~he Y ~xi~ to a carriage suppor~ 68, whlch in ~urn 16 slldable along the Z-axis w.ith ~e~ecl ~o th~ base 70 o~ ~he actuator unlt.
Aooording to ths prefPrred embo~m~nt o~ the present inventiotl, the actuator unit comprise~ a du~l axLs actuator for drivin~ eacl~ wo~kplece trans~erring unlt and e3sentl~11y consists of ~ llftin~ fluid cyllnder ~2 and ~ transl~tlng ~luld cylinder 74. The liftlng ~luid ~ylinder 13 atta~hed to t~le act~ator unl~ ba~c and ~t~ cyli~r rod 73 i~
connected ~o the ~rriage support. Tha transl~ing fluid cylinder i~ attached to the carria~e suppOr~ and i~
~ylinder rod 75 i~ connected ~o the tr~n~fer carriage.
Referring now to FIGU~ES 7 and 8, the op~r~lon ~ a du~l axl~ actuator for drlving all actuator unit w~ll bc described. By extendlng rod 75 of the translatlng fluid cylinder 74, ~ransfer carriage 34 ls moved ln the Y
dire~tion wi~h re~pect to suppo~t 68. The ~olid line~ o~
FIGURE 7 6how ~he t~ansfer c~rrlaye 30 ln the wor~pieoc engaging po~ition, wi~h th~ retrao~ed po~ltlon ~hown in ph~ntom. The action of the il~tln~ fluid cyllnder 7~ ~nd its rod 73 in ~oving t~e transfer ~rl-lage 34 and c~rriage ~upport 6~ in the Z directlon ls sh~wn in ~I~URE ~. ~h~
solid line~ ~how ~rans~er carriage 34 in i~s h~ghc~t~
workpiece lif~lng pos~tlon with ths lower po61tion ah~n in phan~om. Movement o~ the tran~e~ ~rrlage 34 in the ~ and Z ~irection~ causeG the ~r~nsfer rail 24, inger operat~r rall Z6, and the plurality o~ flng~r~ 28 ~o move corr~ponfllngly. The~e ~ran~lation~ ovide th~ r~qU~ r~d movements for engaging and li~ting worXplece~ W, before transl~tion in the X direction ~o the next work ~tation 14, ~ollowed by lowerlng and retrac~ln~ fro~ the workpiecc- W, to enable olearance ~or the next ~rok~ o~ thQ pre~6.

1 3 1 1 ~38 Syn~hronization o~ ~11 the actuator unit~ 30 eupporting A tran~fer rail 1~ achlsved by utili~ing a cen-tralized cont~ol unl~ tv plo~ide pre~u~izsd ~luid throu~h ~luid ~ondu~1: to dr~e eac:h indlvldual llf-ting fluld cylinde~ 72 ~nd translnting ~luid ~yl~nder 74 in the worXpleee tran~fer ~y~tem 10.
Schema~ically s~own ln ~GURE g are the llftl~ly flu~d ~yllnder~ 72 and tran~lat1ng flu1d cylinders 74 for driving two dife.rent ac:tua~or uni~s ~eqcrlb~ prevlously. Also E;hown i a source ~luid ~ylinder 76 ~lth cyl~nder rod 77 att~c:hed to ~ rack 7~ al~d pinloll gear 80. A rs:~a~y motor 82 operating through a rack 7~ and pinioll gear 80 provi~le~s reclproc~l mo~lon to cylinAer rod 77 o ~ource fluid cylinder 76. Source fluid cylll~ r 7~, mot~r 82 and the rac~c ar.d pinion connectiJlg the two are ~hown ~n detail in FIGURES 10-12. In the illu:~ra'ced embodimerlt, the strUGtUre o~ ~IGURE~ 10-~1 i8 moun~ed t~o longitudinal support 32 ~d~ a~en'c t~le ~loor a~ ~;hown ill FIGURE ~a .
The li~ting fluid cyllnder 72 an~ transla~ing flui~
cyl~nder 74 have fluid por~ A and s di6posed on oppo~i'ce eide~ OL~ the~ r plstons 71 ~ac}l of which are connected ~o ~imilarly denoted port~ on each slde o~ tiource cyllnder 76.
~ pi~;ton 71 of sour~e cyllnder 76 iB driven toward lt6 ~luld port~ denot~ y A, ~luld ls for(~e~ ou~ of each por~ A ~o dri~e each set Or lif~lng fluld cylinder~ 72 ~nd 1 31 1 ~3~

tr~n~latin~ flui~ ~yltnder~ 74. Ini~lally, ~o~ 75 4f ~he tr~nslating cyl~nder~ 74 ~ncounter much le~s resistance ts mo~ent than do the rods 73 of the lif~ing Pluid cylinder~
72, duo tG the w~yht ~P the transPer rail~ 24, finger opera~or rall~ 26, an~ the fin~ers 28 for el-~a~ing ~ol-kpieces W, ~hich bear do~ upon and mus~ be r~i~ed ~y ~he li~t oylinders 72. As a con~e~uence, the ro~s 75 of ~he tran~latlng cylinders 74 first extend oausing ~he fingers 28 ~Q engage the workpiecas W. once the rods 75 the trAnslatlng c~linders 74 are fully extend~d, ~he ~od~
73 of the li~ing cylinder~ 72 extend due to the now lessar res~tance a~tiny against th~ir motion. Thi results in the li~ting of the transfer r~ils 24, ~inger operator rail~ ~5, ~nd tl2e ~lnge~s 28 hold1ng 'che wo~kpiece~ W.
Durlng ~he se~ond h~lf o~ the cycle, xod 77 o~ the ~Otl2:'C~ fluid cylinder 76, i~ ~orc:ed tow~rd the fluid por~s ~eno~ed by B, due to t~e rotary motor ~2 ~cting through the rack 78 an~ plnlon ge~r 80. ~luid i5 ~hus orc~d out of the fl~id ports denoted B i~to fluid conduit %4 w~ich Pe~ds the flUid po~t6 ~ of the tr~n~l~ting fluid cylinder 74 and the li`ting fluid Gyllnder 72. ~urlng this part of the cycle, thR weig~t o~ transf~r rail~ 24, finger operator rails ~, ~ing~r~ 2~, and associa~ed wor~pieces W, as~st in ~he ro~r~ctio~ of ~h~ rods 73 of the lif~ cyli~ders ~2. s~cau~e ?5 ther~ iB less resis~ance to the mo~ement, the rQds 73 o~

~- 2~ ~ 1311~3~

lif~lng cylindRr~ 72 re~ c~ ~ir~t, ~ollowed hy the r~raction of the rod~ 75 o t~e ~ra~latlng cyl~nd~r~ 74.
Thus, the transferring mechanism lvwer~ the workpleaes W and then retr~cts t~ ~lnger~ 28.
In ~he p~e~erred em~odiment or th~ invention, a ~in~le ~ource cylinder ?6 is used to ~upply fluid to ~ll set~ o~
liftlng fluid cylinder~ 72 and ~ranslating fluid cylinde~s 74 located in the di~fe~ent actuator unlts 30. ~hi~ re~ults in an automatic ~ynchroniæation of all a~uator UnitQ of the ~ran~fer pres~ without gear4, cams, com~llc~ted mechanlaal timing device~, or complex alectronic 3er~0mechanism~.
Rather ~han u~ing a ~ingle ource cyllnder 76, a~ ~ho~n in FIGU~E 9, a ~erieq of smaller diameter our~e ~ylinders can be used, each one driving a tran~Ler~lng fluld cylind~r and a lif~ing flui~ c~llnder 78. Synchroni~atlon can be achieved by ~im~ltaneously drivillg all sour~e cylinder rods 52 wlth rack 5G.
ln ~he preferred em~odlment o~ -the pr~ent lnventlon, ~ luid oylinders are ~lngle rod Rnd~d. ~n o~har embodiments of the lnven~ion, all ingle rod erlded ~luid ~ylinders oan be replaced with double rod ~nded cylinder~
which h~ve rod~ ex~endlng out o~ each cylinde~ cnd. S~ch ~ingl~ and double ended rod cylind0r~ ~re ~ommerci~lly avallable and well known ~o tl~o6e kllled in ~hc a~t.

-- 25 ~- 1 31 1 438 Hence, the h~reln workpiec~ tran~;f~ 3tem permlts3 ~he plurality o~ workplec:e~ W to b~ moveà along all thr~
axes of ~novement. Thu movemen1; o~ a ~3ingle ~o~};plece W
during ~ typic~l cycle of tran~;fer pre~s 12 will n~ b~
de~cribed. In order to perml ~ ~he workpiece W to be lo~àed onto tha tran~er pre~E;, typically ~che pal r oî ~inger opera~or ralls 26 are made longer ~chan t~he re~k o the system. As~;ulne tha~ ~u~h loadlng is perormed when ~che workplece f~nger operator~i ~re in th~3 rai~ed, engaged 1() posltlon ~hown in solid llnes ln ~IGURE 1~. Th~ , llft cylind~rs 72 are in their extenc~d ~o~3itlon and tran~latiny cylind~3r6 74 and transfer carrlagçs 66 are al~30 ~xtonded.
By operation o~ the previou~;ly ~e~ ribed l~elt drive ~y~em, workplece w 1B ll~ade to ~ra~rel nl~g the X ~xi~3 ~ow~rd the firfit work ~tation 14. A~ ~oon ~19 i~ reach~ a pre~ermilled correct po l~:lon along the X 2Ixl~ for proper all~nmen~ wl~h upper and lo~rer dies 20a ~nd 20b, movement along the X axis w~ll cea~3e, and lift ~yllnder will be retra~ted, ~hereby t;:au~ing lowering oP the workpiece W ln'co the operational positlan. Tran61atiny cylinder 74 and t;ran~f~r ~arriacle 34 wlll also be re~crAc~ed t~ dlsengage wor~piece W from flngor operator6 28. ~he r~m 16 will then be operated to :;au~ stampin~ o~ the wor};piece W between die pleces ~Oa an~ 20}~. A~ter completion o~ troke, ram 16 wlll 1;1 ~t. During the tlm~ wl~en th,e f .ir~g~r oper~tor~ are ~6 ~

disengaqed i~rom worXpiece W, c~urlng ~h~ ~trok~ c~ the ~am, if the die coni~igurat~on permlt~ th~ ~el'c drlv~ 3y~t~m may reciprocate f in~er operator rail 26 ~lon~ 'che X axi~ in an opposite direction, thu~; ~aU~ ng ~ new 6~'c o~ f inger operato~s 28 to be in posltion for enyageme~t with wo~kple~e W~ T~ansf~r carriage 3~ wlll ~hen move along the Y ax~
into it~ extended position, c~usin~ angacJemen~ o~ finge operators 28 with the wo~kp~ec.s W. ~ift cylinder 72 wlll n~ov~3 rod 73 along ~he Z aXis into it;6 ~?x~el~ded posltion to lift t~e workpiece ~as~ lnto the po~ition ~hown ln FIGURE
12. After engagement o~ ringer operators 2~ w~th ~or3r~piece W and the lifting of the wo~kpie~e/ a~ des~ribed above, the belt drive sys~enl will ~hen displace workplece W ~long ~he X axl~ ~or a ~ufficient distance tc~ c:ause it: ~o be align~d with ~he n~x~ work ~ation 14. The cycle is then repeated.
~t each cycling o~ 'che trans~er 6y6tem lO, El plurality o~
workpieces are trans~erred be~ween e~cll ad~ a~ent work ~tation 140 In order ~or a 61ngle workplece W ~o tr~vel ~hrough all o~ ~he plurality o~ work s1;~tions 14, it will be necessary ~or ~he syst~3m -to cycle a~; many tlm~. a~ ~hç~ro ~ro work atatlona 14.
Obvioualy~ in order 'co keep the ~yfitem operating correctly and a~ lently, it 1~ necess~ry ~h~t each one o~
the ~ingl~ di~;placements of t:he plu~ality o workplece~ St ~5 through all three ~Xe~ mu~t ba per~ormed accura~ely wl~h -- 27 -~
1 31 1 ~38 re~pect to bot~l distance di~placed ~nd time o dlsplacement.
To that end, lt i~ contempl~ted that each transer r~ nd accordingly the plurali~y o~ actuator~ 3~ ~nd b~lt drlv~
~y~tems associated therewith, be indepen~Qntly controll~bl~.
The independent control mean~ (not ~hown) for e~oh ~ide o~
the transf~r ~y~em i~ connected to a centr~l ~on~rol].~r 60, ~hown in FIGU~E l. S~n~or m~an6 such as an ~h~olute po3ition transducer ~no~ ~ho~n) are asfioclated wt~h ~h~
pre~ ram ln a well-known manne~ are uYcd to 6ense the position of the rams 16. By feeding lnformation ~rom th~
sensor means ln~o central oontrol mean~ ~0, the operatlon o~ e~ch mecha~tcally independellt si~e of ~y~tem 10 may bo ele~tronic~lly coordinated ~o tha~ tran~er ~nd alignment of th~ plur~llty o~ workpisces w i~ synchronlz~d with one another an~ wl~h the op~ratlon of tr~n~fer pre~s 12. ~h~
can be a~o~plished by ~lmultaneousl~ actua~lng, ln the proper seq~ence, the v~rlou~ motor me~ns for the a~tua~or unlt~ 30 and-the ~rive helt ~y~tems for eaGh tranefer ~y~
10 on ea~h ~ide o~ tho preBB.
Since each ~ran~r ~y~tem 10 on each ~id~ o~ tr~n~er pres 12 1~ independently conSrollable, the ~y~te~ 10 may be used to realiyn an~ repo~l~ion the plural~ty o~
wor~pie~e~ W ~ required by each ~amping oper~ion, For example, ~he right mem~er oE an opposed palr o~ flnger operator ralls ~6 may be ma~e to move ~t ~ ter ra~e than -~ 2B -~ 1 31 1 438 th~ left memb~r. ~ch movement would ~se ~he workpl~ce W to rot~te somewha~. Blm-larly, movem~nt of the aO~ tOr unlts 30 may be varied a~ neces6ary to ad~u3~ to required operAting condition~.
A~ ~hown in the preferred embodlment~ ~e~uator uni~6 30 ar~ dual axls hydraull~ actuators ~8 described above.
~aln howaver the inVentiOI- c~ntempl~t~d he~ein i~ no~.
l~ite~ to thl~ type of actua~or, but mAy lncludc other .. suitable means Or impartlng llnear motion.
It may be seen how ~he the~-eln sy~em i~ ~daptable for operatlon with a wlde variety O~ different trans~cr pre~6 deslgns o~ ~arylng filzes. Thu6, in an in~tall~tion having tran~er presses of various ~ype~, it 1~ po~ible ~o move the operating ~ystem 10 ~tom on~ tr~ns~e~ press to another.
1~ The tr~n ~er syste~ i6 modular, and as many ~omponents may be ~ded a~ ara neceB8a-~y ~v ~ccommoda~e th~ ~iz~ o~ the pre s ~nd t~e num~er o~ work ~tatiOtl~ therein. ~he Qc~uator unit~ 30 may be u~ed with exis~ing sy~m~ havlrlg dle mount;ed trans:~er r~ whlc:ll utllize ~ Gro.~s ~lide braclcat.
Hence, retro~itting o~ exist~llg systelns is inexpens~ and ea~i Furthe~more, whell ~le chnng~ operati.ons are necessary~ i~ ls much easler to die~:3emble t:~¢ sy~tem of the pre~en~ invelltioll than is the c~e wl~h prior Art 6y~tem6. Furthermore, in con~rast to prlor ~rt sy~ems wher~ e various actuator, motor ~nd drive componen~ are ~- 2~ -- 131143~

mounted dlre~tly on ~h~ trans~er rail ~nd lnter~re w~ th operatlon of 1:he press, the 2~ctuators, mo~ors ancl driv,~3~ o~
the preSe~t system are deploye~ outboard of the pr~S6 ~ el~
and ~upported independ~ntly frolll the trAn6fer and f~nger oper~tor rails, thu~ re~ulting ln ~A~ler oper~ion, a~ well a ln a reduction of ~he b~lk o~ the rail nece~ary ~o upport the ystem.
In ~n alternate embo~im~n~ ~ho~n 13~ FIGU~E ~3 ~ the trans er sy~em o~ the present lnvention ~ moun~ed or depend~ from the upper ~ationaL-y press crown shown ln FI~URE 1 ~ia a s~pport ~rame ~9. Thi~ transfer ~y~tem a~rangement ~unctions ln the same man~e~ ~ p~cviou~ly de~crlbe~, but greatly lncrea~e~ avail~bl~ ~loor 3pace ad~acent the transfer pL~SS and provldes unob~tructcd acce~6 thereto. As wlll be apparen~ to those skilled in the ~rt, ~upport ~rame ~ may take vario~ ~orms, ~nd the dlmension~
of the ~ua~or unit~ may vAry to a~o~mod~tc ~uch overh~ad mounting~
Wh~le the herein embodiment has b~en de~cribcd ln~talled ln a transf~r pres~, lt 1~ ~o~templated that ~t may be adapted ~or u~e ln any ~y~tem re~uirlng repetitl~c tran~fer Or a plurallty of workpie~e~ ~rom one equidistan~
worX ~tation to ~no~ler. For exa~ple, 3uch rep~tl~iou~
tran~fer may ~e ~leeded ln oper~ting a punch pres~, a coating ~y~tem, a paint ~prayer, et~. Furthermor~, other ~u~h ~30__ 1311438 appll~ation~ ma~ occur tc~ one ~k1lled in th~ art ~lthout depar~ing ~rom ~ pirl1; o~ th~. h~r~in invention.
Therefore, the scope o~ ~he p~ent lnvention is not limit~d to the embodiment~ and exempli~lc~tions de.picted 5an~ d~cribed h~rein, but rath~r by ~e cl ~im~: append4d he~o.

Claims (21)

1. For use in conjunction with an article forming press which includes a ram having an upper die associated therewith adapted to be driven along a path of travel in a Z-axis and engageable with a lower die supported by a bolster for forming a workpiece inserted therebetween, a transfer system for transferring workpieces between work stations aligned linearly along a central X-axis perpendicular to the Z-axis, to perform a predetermined sequence of operations on the workpieces, said system comprising:
a transfer rail extending longitudinally in spaced and parallel relation to the X-axis and having a finger operator rail mounted thereupon for movement with respect thereto in a direction parallel to the X-axis, said finger operator rail being mounted entirely between said transfer rail and said central X-axis;
a plurality of workpiece gripping finger operators mounted on the finger operator rail at equally spaced locations thereon corresponding to the spacing of the workstations, said finger operators extending laterally inboard from the transfer rail in a Y-axis, perpendicular to and toward the central X-axis and Z-axis and each terminating in a free end having a workpiece engaging section adapted to engage the workpieces and transfer them between adjacent workstations; and at least one actuator unit supported independently from the transfer rail and disposed at a location displaced laterally along the Y-axis from the article forming press, said actuator unit having a transfer carriage which extends therefrom in the Y-direction and which is operative to move the transfer rail along both the Y and Z axes;
drive means for said finger operator rail supported independently of and associated to move with said transfer rail; wherein said drive means and said actuator unit are powered by motor means which remains stationary with respect to the movement of said finger operator and transfer rails.

2. System of claim 1, further comprising means for centrally controlling movement of the transfer rail and finger operator rail to synchronize travel of the workpieces through successive work stations is timed relation with performance of the sequence of operations.

3. System as defined in claim 1, wherein one of said transfer systems is positioned laterally along the Y-axis on each side of said article forming press running essentially parallel thereto to cooperatively transfer said workpieces between said work stations along the X axis.

4. System as defined in claim 3, wherein each of said transfer systems positioned laterally on each side of said press is mechanically independent of the other and electronically synchronized with the other to simultaneously transfer workpieces between the work stations.

5. System as described in claim 4, wherein said transfer systems are electronically synchronized to a common input signal corresponding to the position of said ram along said Z-axis with respect to the work stations.

6. System as defined in claim 1, wherein said actuator unit is powered by motor means which remain stationary with respect to the motion of said transfer rail.

7. System as defined in claim 1, wherein said actuator unit comprises a dual axis hydraulic actuator for driving a transfer carriage over the Y and Z axes;
the transfer carriage experiencing different resistance to motion along each axis, said hydraulic actuator comprising a first fluid cylinder having a single input fluid port and an internal piston and cylinder rod drivingly connected to said transfer carriage to move it along one of said axes, a second fluid cylinder having a single input fluid port connected in parallel with said first cylinder input port and an internal piston and cylinder rod drivingly connected to said transfer carriage to move it along the second of said axes, said first cylinder piston and cylinder rod constructed to initially operate with less resistance against motion than said second cylinder piston and cylinder rod, a fluid source means connected to said input ports of said first and second fluid cylinders providing the fluid to both cylinders under the same pressure, whereby that cylinder rod experiencing the least resistance to movement extends until its resistance to motion increases beyond that of the other cylinder rod, followed by the extension of the other cylinder rod; and said first and second cylinder being independently operable such that operation of said piston and cylinder rod of said first cylinder does not change the axis of operation of said piston and cylinder rod of said second cylinder.

8. System as defined in claim 7, wherein said fluid source means further comprises a third fluid cylinder having an internal piston and rod with a fluid output port connected to the parallel combination of the fluid inputs of said first and second cylinders.

9. System as defined in claim 6, wherein said motor means for powering said actuator unit comprises:
a rack coupled to the rod end of said third fluid cylinder;
a pinion gear engaging the rack; and a rotary motor having a shaft for turning said pinion gear, whereby the rod and piston of said third cylinder can be translated toward its output port to force fluid through the output port of said fluid cylinder.

10. System as defined in claim 1, wherein said transfer system is mounted on a movable modular support such that said transfer system can be easily moved with respect to said transfer press.

11. System as defined in claim 1, wherein said article forming press includes a stationary press crown overlying said ram, and said transfer system depends from and is supported by said press crown.

12. A transfer press automation system for transferring workpieces along a series of equally spaced, aligned workstations at a central axis of a transfer feed press having a ram associated therewith, said system comprising:
a transfer rail extending along and in spaced relation to the central X-axis and extending longitudinally along a side of said workstations;
an individually controllable finger operator rail mounted on an inboard side of said transfer rail for reciprocal movement with respect thereto for a distance equal to the spacing between adjacent workstations and in a direction corresponding to the X-axis and defining the direction of workpiece movement through the workstations, said finger operator rail being mounted entirely between said transfer rail and said central axis;

linear drive means associated with said transfer rail and its associated finger rail, said linear drive means operative to effect the movement of the finger rail;
a plurality of workpiece-engaging fingers supported on the finger rail at equally spaced locations thereon corresponding to the spacing of the series of work stations, each of said fingers extending laterally away from the transfer rail along the Y axis perpendicular to and toward the X-axis and terminating in a free end having a workpiece engaging mechanism mounted thereon adapted to engage the workpieces; and an actuator unit associated with the transfer rail and disposed along the Y-axis and on a side of the transfer rail opposite the series of workstations, said actuator unit adapted to support the associated transfer rail and impart reciprocal motion thereto in directions corresponding to both the Y-axis and a Z-axis which is perpendicular to the X and Y axes and defining, respectively, the direction of finger operator movement into and out of engagement with the workpieces and the movement of the finger operators for raising and lowering the workpieces;
where said actuator unit and said linear drive means are powered by motor means which are mounted independently from and which remain stationary with respect to said finger operator and the transfer rails.

13. System of claim 12, further comprising means for centrally controlling movement of the transfer rail and finger operator rail to synchronize travel of the workpieces through successive work stations in timed relation with performance of the sequence of operations.

14. System as defined in claim 13, wherein one of said transfer systems is positioned laterally along the Y-axis of each side of said transfer press running essentially parallel thereto to cooperatively transfer said workpieces between said work stations along the X-axis.

15. System as defined in claim 14, wherein each of said transfer systems positioned laterally on each side of said press is mechanically independent of and electronically synchronized with the other to simultaneously transfer workpieces between the work stations.

16. System as defined in claim 15, wherein said mechanically independent transfer systems are electronically synchronized to an input signal from means signalling the position of said ram along said Z-axis.

17. System as defined in claim 12, wherein said linear drive means is supported independently of and mounted to move with said transfer rail.

18. System as defined in claim 12, wherein said linear drive means comprises a belt drive system.

19. System as defined in claim 12, wherein said actuator unit comprises a dual axis hydraulic actuator comprising:
a first fluid cylinder having a piston and attached rod, with first and second fluid ports disposed on opposite sides of the piston;
said first cylinder, piston and rod constructed to initially operate with less resistance against motion than said second cylinder, piston and rod;
a second fluid cylinder having a piston and attached rod, with first and second fluid ports disposed on opposite sides of the piston;
a third fluid cylinder having a piston and attached rod, with first and second fluid ports disposed on opposite sides of the piston;
conduit means for connecting the first fluid ports of said first, second and third cylinders and the second fluid ports of said first, second and third cylinder; and means for reciprocatingly driving the rod end of said third cylinder in a forward and return stroke, whereby during the forward stroke the same fluid pressure is provided to said first fluid ports of said first and second cylinders and when, the rod of said second cylinder acts against a greater resistance to movement relative to the rod of the first cylinder, the rod of said first cylinder extends until it reaches a stop, followed by the extension of the rod of said second cylinder, and during the return stroke, the same fluid pressure is provided to said second fluid port; of said first and second cylinders, and the rod of said second cylinder retracts due to a greater biasing force promoting its movement in the retracting direction relative to the rod of the first cylinder, followed by retraction of the rod of said first cylinder; and said first and second cylinders independently operable such that operation of said piston and rod of said first cylinder does not change the axis of operation of said piston and rod of said second cylinder.

20. System as defined in claim 19, wherein the reciprocating rod motion of said third cylinder actuates said actuator unit in the sequence of engaging the workpiece followed by lifting the workpiece, next followed by lowering the workpiece, and finally followed by releasing the workpiece.

21. System as defined in claim 19, wherein said means for reciprocatingly driving the rod end of said third cylinder comprises a rotary motor, a rack coupled to the rod end of said third cylinder, and a pinion gear engaging the rack and mounted to the shaft of said rotary motor, whereby the translation of the rods of the third cylinder can be controlled by the rotary motor.