CA2060230C - System, method, and process for computer-controlled manufacture of three-dimensional objects from computer data - Google Patents

Abstract

A method and process for computer-controlled manufacture of three-dimensional objects involves dispensing a layer of liquid, insoluble material (25) onto a platform (15) at predetermined locations, which them hardens. A second media (35), preferably water soluble, is then sprayed onto this layer to thereby encapsulate the hardened insoluble media. The uppermost surface of this encapsulant is planed, thus removing a portion of the encapsulant to expose the underlying insoluble material for new pattern deposition. After the resulting planing residue is removed, another layer of liquid, insoluble media is dispensed onto the planed surface. The insoluble media can be of any color and may vary from layer to layer, and from location within a layer to location within a layer.
These steps are repeated. until the desired three-dimensional object (55), surrounded by a mold, is completed. At this point, the abject is either heated or immersed in a solvent, thereby dissolving the mold and leaving the three-dimensional object intact.

Description

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Field__ of the Iavent.i~mm Without l.3initing its scope, this invention relates to rapid protr~txping, and mare particulax~.y try a system, ~netht~d, and pracess ~c~r ma~lu~acture of three-~ciia~e~,sir~nah o~ajects from d~~ep~tt~~ data using ccmptater~-e~antrol.Ied dispensing o~ mu3tipla media and selective iaateria7. su~bbtsactioa.
p~s~rx~'~~.oa o~ the Related.
~s Grampl~x designs increase the need for rapid prototype fabrication, this reed for imm~dia'te f~ed~7~~lt requires model. or machine shops to fabricate complex parts in low volume with ma~~naxnuan setup anc~ run°time. l~3ost fabr.icat~.en m~thcds. hcwe'~er, ar8 ~ln~a, GompJ.ax, and exper~siv~e.
dahile manual machining a.nd farrnmg methods are o~t~n cheap and effective for s~.mple designs, the costs caxa be prohibitive for the iterations requiraci of co~npls~.~ parts and assembli~~. Coanptater Nuxner~.cal~.y ~ontsoJ Zed (CMG) ma,ch.~,rn~s are ~aidel.y used, to automate cr~mp~.ex fabri.~ation, beat are dost:~y to ~parat~~ mainta~.n, cad program just. for v~~e-o~-a-ki~nct prod~actiarz.
xhe .most wa,dely ktso~n sjrs~~m in the field o~ rapid protfl°
typing is sterec~lithcgxaphy. This system fabricates complex parts from computer data by ~~ap).aYing a. set Cf cnmptter°cont~cllec~
aiirrQrs tc~ scan a laser beam aMross selected. tyro-dimensioxaal. areaw of liquid phtatopalymer cor~tair.ed in a v~.t and thereby form a layer o~ solid pQlyrner. The cu~r~.~d ~,ayer. ~rt~iGh is attached to a plat~cxm, a.a ldvaered into the vat and nce~w layers are generated one, on top Qf the pr~avious layers to ~or~n a three-di~aensional pant.
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~~~~2~~0 supports are; nut, assay frozta the desired object. hd~ditioxaal, light exposure is r~c~uared to so~.ir~~.fy any trapped lagaxa.d.
~ ma jor drawback to stex~:olithe~e~raphy and similar apprcaaches is that support structures m~rst be desigsaed to join the object to the platfo~'n and att,aoh any cwerhangs, large spans or disjoint areas. the addition of these structures to the a~ode7. and subae~ent manual removal from the part daring alearr~.ac~ is l~or a.a~tensi~ae and often rewires special skills.
Another drasabs.ok is the additional occupational, and environ-~
mental safety measures r~qui,rE~d with the use of .lasers or resins.
~'he chemica~.s used in this pr«cess and in c~.eanup rewire special handling, ventila~tiorr, and storage to protect the operator and the worIs place. ,~igh~ ~rolumes of waste are generated is resin goval and cleanup. 'The photopolymer is expensa.ve and nonrecyclable. A11.
of this malces installation in common work areas or offices is~praotical for size and environmental reasons. Furtherauore, because of thc~ delicate natura~ 4f lasers and optics, installation and cal~ratioa is very difficult .. Maintenance is expensive due to system complexity and laser a~~sts.
~.nother lithographic fax>raoation method is selective laser sintering. This method emp~.oys a heat laser to fuse ~six~ter?
selected areas of powdered maternal such as wax, plastic, or petal.
1 In practice., a vat of powder is scanned by the laser thereby me~.tia~g individual pa.zticles which then stick to adjacent particles. Layers of the ~Eu~ed powder are processed sequentially like ph~topc~lymer lithography. Ara advantage of the s~.rttering aaet~~aod is that the non-heated po~rder serves as a support for the part as it is formed. this means that the non-heated powder' eat hw shaken or dusted off the object.
Selecti~we laser sin~.ering, however. is alsr~ a octng~lex, expensive optical s~rsteia. The resolution ~f the :~ialal part is limited by the hewn diameter, which is typically .O1"-.02".
Furthermore. in an additional step,, the powder is deposited and levelled, by a rollinr~ baush which requires ether e~,eotro°mechanical . components. ~.nfa~xtunate~.y, levelling fine powrders with a rolling b~xsh often causes n~nlaomc~gan4ous paclring dransity. ~additional~.y.
~h~.le powder c~sts less (mater~.al ~ labor) fan li3d photopolymer systems, pseparin~ a 3D a~aioron layer is difficult. An object. bua.lt from th5.s powder is of medium resol~at~.on, lass a saon~unsform surface a.nd, often, a nox~-°horaog~neous stxuct~are.
Research, has been conducted at t~.~ l~assachus~tt.s Institute of 'technology in fabsicatioxa by three-da.mex~sional printing. xn this research. cexamic powdex is deposited using a e~ide fe~d~r o~rer a wit car txay. h silica binder is then printed ors selected areas of the powder to form a solid crossrs~ction. The process is repeated to fazxa a stac3~ cf cros,s-seatians representing the final olbject.
This appxoach exh~.bits the sata~: powdlor deposit~.on problems as sel,ectiwe laser sintering, along with the additiox~a~. difficulty i.n retraoving unbound powder frcjm ir~teraal cav~.~ties. ~r-~P~~~ores, objects generated by this system axe not recyclable. fhe ~il'~
researc3a is dixected toward thr~ production of ceramic mc~ld,~. Met.a.l or other r~a'~cxials are then ~.n jected or poured irate the meld which is later broken awa~r from the cast pats . t3nfr~r~unat.al.y, the molel° s intaxnal cavities, wha.ch def~.ne the final pants, axe spat easily i.nsp~cted, which leads to are oxpensiee trial and axror process to acquire acctarate parts.
'~dd~.tional pxobl~ts four~c~ with the art ba~r~ been an inah~.lit'y tos provide for variable surface color or use morn than oae material media in the fabriea~k~on of the d~sa.r~d ~bj~~t: remove the media support for overhan~g:~, lare~~e spa~ls or dis joint' arias autar~atically: or provide ,gin automated sys~~t ~0~' physically reproducing, three-dianensional computer d~sigx~s arid images. ~ystams cuxrent~.y availa&~J.e are expensive, the nt~~ia t$~y taSe t~atlsot Yea recycled, and they canx~c~~t ~r4~ride for automated part handla,.ng after fabrication due to t)ae.ir use c~f bulb powdery ~.nd resins, ~ihich require. cs~ntainers rather thaw co~nveyr~r platforms.
Accordingly, ~npro~rements which orrercom~ any or all 4f the~ss problerits are presently desirable.
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zn view of the above p~eobiems associated with the related art.
i.t. is an object of the present invention to provide a computer-aided manufacturing system. apparatus and a method for fabricating an object in more than ~ne material ~led~,a and/or in more than os~e s~arfaCe color .
It is another object of ~Lhe present invention to pscovide an automated systesa, apparatus and method for physically reproducing three-dianex~sional computer designs and images, including auto-mated pant haxadling after fabrication.
It is yet another object, df the present invention to provide a system. apparatus and method for automatically removing the media supgaoxt for overhangs, larg~ spans. disjoint areas and the lake :~ro~n the fabricated object.
It is a further object of the present invention to providA a s~rstem, apparatus and method for fabricatioa~ of an abject . using recyclable media. ' these and other objects are a<:complished in the systexa, method, aaad process of the present invention_ In preferred embodiments. a method and prneess fc~r computer--controlled ynanu-faeturing of desired three-dimensional objects involves dispensing a layer o~ liquid insoluble mz~ter~.a1 onto a platform at predeter-mined locations. This liquid medaa hard~ns ar~ce it c~ntacts the platfor~s. Although usiag a water sa~hable platfox~a is prey~rabl,e, the platform can be pernnan~nt without viola~.ing the spirit ~~ ~t~le invention.
h water soluble media ~.s the sprayed to encapsulate the haxden~ed insoluble media _ T2aa. s water soluble media also hard~:as on contact. The uppermost surface of this encapsulant is planed, 'there,by remaving a portion o F the grater soluble encapsulant to e~pos~ she underlying ins<aluble material f~r .new pattern deposition. fhe resultiaag res i.due from such planing is reiaoved and another layer of li~s.d insoluble media is dispensed ~n°~v ~.h8 planed surface. These two-dimensional spray patterns are pr~.nted fT-3 5114 - 4 -~~ 'i~ r> > ~i ~~~uerati~~.3 y o~ "~~ac~sed" to Eon a thr~~~d~ons:~onal . o~ jest surrounded by a water soluble mold. Thos cycle of dispensing of a 1~,c3vid ix~solub.le media layer and water solu~alE encapsulaxlt layer, followed by planing and removal of planing residue is known as a pg~,n~ cycle and continues unti..l the three-dimensional abject is comgleted. At this pointy the object is immersed in watery thereby ~ii~sol.v.a.ng the water soluble mold, le~avixac~ the three-dimensional object intact.
According to another prey sexed emboda~aent a system for aiax~u-tacturing three-dimensional ob jests from coaaputer data comprises at least one abject scanning and image capture device usesd to generate and stare specific dada shout a desired three-d~e~asional object. This data is sent to a microprocessor control system which processes the received data into seqdaential cross-s~ctions of the three~dimensionai object to beg physically rendered.
At least ore dispensing device sprays a J.ayer of at least one eutectic material in predetermined areas on a target surface and at least one nozzle sprays water soluble r~ater~.a1 to encapsulate the layer of eutectic material ba;,ed can input from thQ mi.oroprocea~sar control system. The exact positioning of the sprayed materials is determined by not only the pattern received from the 0117 system.
but also. by a set of linear Fosition~.rac~ devices tlxat move the at least aa~e dispensing device, the at least one nn2zle or the target surface according to instructions receiv~d from the microproc~ssor control syst~a.
Once a layer of eutectic material is encapsulated with the water soluble anaterial, a microprocessor-controlled cutting device planes the encapsulated ~aatasial to expose the uz~derlyiaxg eutectic material. while a microprocessor-controlled vacuum fixture removes the unwanted planed material. Where all of the print cycles are finished, the coanpleted obj~c~ and mold are immersed in a support removal systcx~ employing water, thereby dissolving the water soluble mold and leaving the ehree-dime~ssiona~. object intact.
A major advantage to the system and process of the pxese~tt invention is that selected layers of liquid insoluble material, and xz-:51.4 - 5 ~~ :1 Fd ~ '~ :.~ !~~~ 2~
even selected l~aatioz~~ ~rithi~ a lay~~, pan be colored ~~f~~entd.y than the remaining layers c~f l.ic~aad insoluble material, thereby al~.ovring for a full range of colors and e~rcrythiaaq frgm subtl.a shading to abrupt chaaages of color within the same manaafactuxed abject. This aspect makes it p~ssxble for'. c~aalitYv ~.~tailed visualization models to be manufactured ft~r a snide variety of uses such as scientific, medical, and ge~logical study, t~o as few.
Furthermore, by using moats thazi one type of insoluble material.
varying textures ca..n be aahie~red as w~11. Also, by judicious selection of the insciluble media, such as wax, thermoplastic, etc., and the ease of w2tex soluble media for a anc~ld, the mold media and abject itself is recxclable.
'~h~se and Qther features ,end advantages of the invexation wilt ba apparent tn those skilled ir. the art froaa the following d~taa.led deSCraption og 3 preferred embodiment, taleen together with the accompanying dras~ings, in which:
~ESCRTf~T ~F THE D~lwIttGS
FIG. la is a perspecti~r~ drawing of an automated thrae-dimensioaa.l object manufacturiwg station according to a preferred ~onbodimeast of the present invention:
FIG. 1b is a parspect~.~re drawing of an exa8npla thre~r dimernsional ob j~at manufactured accarding to the present invantiox~:
FIGS . 2a--o are front, tc~p, and haft side views of an~ather preferred embodiment of ~tha rapid prototypinq systeam of Figure la accordia~g to the present invex~ti~an:
FIG. 3 is a perspective view of a microproeessor and water rinse vat according t~ a pxwfexred ernb~diment of the present invention:
FIG. 4 is a process flow disgrace depicta.ng'a process of manufacturirxg a three--dimensi«nal object according to,a preferred '. em~aodiment og the present inv~'ntion:
FIG. 5 is a perspective view of a printhead inspECtion and fI-15114 - 6 -purging ~~~~a~n acc~~~g tc a ~~~f~rr~d ~an~ of th~ p~s~at invent.ioa J
FI~s . 6a--b axe wav~fcxtrs diagrrams reflecting detector output accoxcting to a preferred embodiment of the pxes~nt invention.
FI~a. 7~,-c degict viewa of the resulting structure during selected prr~cess steps fray manufacture of a ttaree~-da.naensioraal s~~jaCt ~~ of a low melting point ~aaterial according to the g~raterrad e~odi~mea~t of the pxes~nt invention of F=G. 4: and FI~s. Sa-c degict views of the resulting structure during selected process steps for manufactu~:e of a thxee-damensional.
abject at~ade of a high melting point or high viscosity material according to a preferred dazneat of the pxesent invention of FTG. 4 , Correspanding zazamexals arad sq~ols in the different figures refer tca corresponding parts :.mless othe~s.se indicated.
'b7E'3°AII~ 15ESCFt;C~T~OZd OF A PR~~~L9 EF~OD
The present invention fabricates exact copies of a SAD model without tooling and caxa caper,~te in as ordinary warp environment because it is environmentally safe.
Whenever CaD images are referread to herein, it should be understood that .images from other abje~:rt scanning and imag~ capture devices can also ba fabric;ated to scale usa.ng the present invention. Without limiting the scope of the present iave~staon, examples of such devices cott~nonl.y used include computer-aided degiga~ ~ (CAI7) , coar~puter-aided manufacturing (eA2~t) , computex-aided engineerio.g (GAE) . computer, tomagxaphy (C'~) , magnetic resonance imagizag (ICI) . positronic eraa.s~cion tomogxaphy (f~T) . laser profilers, confaca3, scanning microscopy (CSI), IR irnagers, electzon microscopy, etc. In this fashion, an innu~neraraJ.~: variety of subjects. including models of living creatures or plants, and ev~n.celestial badias can else be objects reproduced in color vaith this invention.
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E°igure la is a perspective c3ra~inc~ of an automated three-dimensi.onal abject manufacturing station aGCOrdinq to a preferred ~bodiment of the present inve~atican. One or more ma.croprocessor-Gontrolled dispensing or pra.nting devices 10, vrhich comprise garinthead 20, pump eutectic m<~.tera.als i~x liquid state. either as droplets or narrow streams, toward a generally planar target.
surface such as platform 15. nlatfo~ 15 servres gas a base for the first. and subsequent, pr:i.nting and spraying opexatioris.
Independent, computer-addressable dispensing devices 18 are preferably ix~kjets, such as those on. colored plotters or an3tjet page printers, adapted to spray melted waac, plastic, or other material. Print devices 10 within printhead 20 are turned on or of~ accord3.ng to a t~a~o-dia~mngional data map st~red and relayed by a microprocessor.
"Microcomputer" in some contexts is used to mean that, micro-camputer requires a mepaory and "microprocessor" does not. As used herein these terms can also be synonymous aa~d refer to equivalent things. The phrase °processing circuitry"' comprehends hSgCs (application specific integrated circu:i,ts) , FAL (programmable array logic). ~'~ (programmable logic arrays). decoders, memories, non-sof'tware based processors, car other circuitry, pr digital computers including microprocessors and micracoseputers of any arohige~cture, ox coa~inations thereof . Words of iraclusio~a arc to be interpreted as noaexlxausti ve ~in considering the scope e~ tote i.nventiQn .
An injection meld took. (not shown) is used for fabr3.cating platfoz~a 15 from a water soluble materi.al_ The mold tool tray have pressure or vacuuxa ports as well as coo~Lixigdheating mechanisms to accelerate the molding procasg . Addationally, tha mold tool cavity may kae of varying cross-sectional. thickness depending on the geometry of the desired object. Platfoxuas made of metal or other non-soluble materials such as ceramics ar special plastics are less desirable than water soluble platforms because they diminish th~
area exposed to solvent duxinc~ the v~ash phase.
Returning to Figure la., c~ne or more materials 25 axe cony~rted TI-:1511 - 8 ~~ ~a r.~ . a Sl '~.i st~ 'i~ F
by heat ~r ~h~~x far~c~~~ to a liquid state. and th~rra ejected by printhead 20 to strike platroraa IS where materials 2S rapidly so~.a,di~y aid adhere, _ thereby creating a two-dimensional patterxa layer of varying cross-section. Several such layers formed Se~~e~tiall,y on top ~of each other are known as a stac3c. It. should be realised that although object 5a, oomgrising a stack of layers of materials 25,35 deposited in accordance with ~nic,roprocesse~r instruction, is portrayed in Figure la with visible layers, this is done strictly a~or eatplanatic~n and clarity. In practice, each layers are preferably .405 inch in degth and are v~,x~uaJ.ly undetectable by the hunnan eye.
One ox wore heated z~ozz lee or guns 34 , ( seers better in the e~boda.~er~t of Figures 2a-c) s~,ray a random coating, of pref~rably water soluble material 35, thereby encapsulating previously pr5sated non--random, insoluble patterns. Material containment and delivery system 40, discussed in more detail in connection with Figures 2a~
c, provides containers for ea~zh df mater~.als 25, 3S to k~e deposited s.ccording to the present invention. By using heated naxxles or guns 30 for dispensing of water soluble material 35, printhead 24 life is extended because it is not utilized for az~y water soluble' material. Additionally, a sig~aificarit reduction in computer data volume and processing is realized du~ to the use of random spray device (s) 30, which do not requir~ detailed instrua--tious to direct the sprayed particles to spncifi.a x,lr points.
hater salable material. 35 is prefera~aly solid at room temperature, exhibits a raelt.~:d viscosity ~rhich is compatible with cornmora paint spray type e~uipmeast. and has good machining characteristics after deposition and hard~an.ing. Material 35 supports and encapsulates the desired insoluble three-dimensional object daring fabrication. ~s can be seen in Figure iT~, 'the water dispersion characteristics cs material. 35 assures ~a very clean three-dimensional object 55, com~aosed ~ca~ only material 25, wall, remain after immersion in a <=ontainer of water.
P, water soluble material is preferred over the stlppcrt materials used with other s~rstexns discussed previously, such as TI-15114 ° 9 ~~~~~ DO
p~wdegs ~~~,tb~ to lcav~ a rough, flaking surface) or LTiT-curably resin tmust be removed manually with a cutting tool or sander).
po~rd~r support methods also do not prcwide adequate holding ford against ob ject waa:page. °~he u.,e of water soluble, os at least lo~a m~3.ting pe~int, materials e~aables users of the present in~enta~a~, unli%e Uther material deposition systoms, to produce complex futures such as caa~tilevers, or suspended objects froa~a ceilings or walls, or swan sozseth.iug, by way e~f example and aaot of lamitation~
as intricate and complox as a ship in a bottle. Additionally, water soluble materials are g'<a~.te inexpensive and do not necessarily need to be printed with priath~ad ZCi, hut can b~
qua.ckly and cheaply sprayed ox~ wig nozzles 30.
,Although using a water soluble aiater3:a.1 as a mold is pre~fmraced, overall., it should be understood that material 3~ could be a lox-molting point anaterial which would then be romoved day e~cposuro t~
heat, pr an alcohol-soluble material which would dissolve why immersed in alc:ohol~ Tn general, dissimilar properties of the mold and object are exploited to ramoroe the mold without affecting tho object. Thus, when the fina:~, layer is printed, the support is zaelted or dissolved away, leaving the threw-dimensional abject intact, an example of which is seen in Figure Zb. These materials, althougi~ frequently not as desirable as water soluble .materials, aro pref~rr~d to the support mat~ria.ls discussed ab~~r~ ire conx~ection with other material ds~positi~a~ syste~ras, and use of sub falls within the scope of the present .zn~re~tiox~.
Positgoxaing devices 45, arxanged along the X, f, ~ axes oaf a Cartesian coordinate system (and sa labelled on Figuro la), move the printhead ZO andlor target. surface 50 according to compu~t~r instructions. target surface 50 is platforan 1~ for the initial deposition layer, and the ~arevious deposition layer foe az~y s~abse~aent deposition layers. specifically, positioning devices 95 can completely define any t2xrEe-dimensional object. preferably by moving target surface 5n horizontally (y) oar vertically (Z) . and by moving pri.nthead 2~ ~aori.zontally (X) acso~a ta.igot surface 30.
Positioning dev~.ces 45 employ circular motor 4~~ to move target TT-l:ilx9 ~ 1.9 -~~ y ~31 ~3 i~
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"ar~r~~~e ~~/ ,~~~ay~rag ~~, a~~ ~~~~~h~a~ ~~e ~~. sh~uld .~1~ n9t°,~d th~.'~
other motors, such as lin$ar motors, could be used instead of It should be realized ~rom the ~utset that posa.tioning d~vices 45 ogt~ld be a volumetric positioning des~l.ce, ~r a planar positioning device operating tagether pith a linear posits~r~2ng device, or three linear posita.oning devices, etc., and such detail should in no c~ay limit the scope of the invent.on.
F'ic,~areg 2a-c are fr~sx~t, top, and left side vieo~s of anot~aer preferred e~abodiment of the rapid prototypiag system of F3c~are la acoording to the present inventa.on. The description of elemeats skxown is Figures 2a-c coxrespond3.n.c~ to those previously described in c~a~~Gti~n with the er~odia~nf, of Figu~ce 7.a is her~by incorporated. As can be seen try comparing ~'a.guares la and 2a-c, the particular positioning of the elements ~f a systeaa according t~ the present invention is i~amaterial, except that printhead 2a and sprayers) 30 are preferably positioned to dispense materials perpendicularly onto target surface 60.
the prototyping system shown ~.~i figures 2a-c rests on a supporting table 56. Cantilever supports 59 strengthen supports 62 to foz-tify lintel suppor-f 64 from which printhead(s) 20, sprayer (s) 30, etc. hang.
One or mores cutting devices 6(1 (best seen in Figure 2a), arranged so as to plane the uppermost surface of target~surface 50 at specified intezvals along the v~!rtical axis of fakarication, rernnve a p~xtian of water solubl~ ~ncapstxlaat 35 axed expose underlying insoluble material 25 for new pattexn deposition.
Cutting devices) 60 also r.ompensates for surface and height vara,ations caused by flow rate differences among multiple print devices 10 ~r~ printhead 20, c~~arpage of the object is ~ also reduced b~acause the ~Slaning action of cutting device4s)~ 60 serves tw relieve stresses induced by m,~terial 25,35 cooling and shrieking.
vacuum head and pumping system 65 (best seen . in Figure 2c) rearoves residue generated dnra.ns~ the planing action of cutting device (s) 60.. The xesa.~lue can be recovered in a filtered canister Tz-15114 ~- lI -~~if~°~'~
d~ t~ h za (not st~oxn~ far dispasal a~ f~a~th~r x~a!~al3.ng. Vacuum fi~tug~ ?0 (bast viexesi in Figure 2a) holds building platform 1S to positioning. devices 45 and, permits signpla, rapid retaoval and replacement of platfarm 1S ~rithout risk of damage ar deforr~tion to p3.atfox~ 15. Ve.euusa fi~ctur~ 70 fugther enables a system according t~ the present invention to provide an optional aaxtc~ated ohjc~ct°
in, abject-apt, aonveya~' ~r rac% ?5 (sho~tn xx~ Figure la) .
6~orls volume 7~. outl.inE~d is dashed lines in k"igure 2a, indiaahes the maacimum object enve~3.ope in which an objet. may be situated as i~, is being printed. Hecause some material eoa natioa~a require printing at ambient t~npcra~tur~s abave room tex~pexatura 4as with metals) or xell bel.n~r (as with water), aa~
er~~'ira~lental~.y-controlled chamber caa k~~ positioned within xorx volume 7.8.
Bulx containers 80 (best seea~ ire ~'igur~ 2c, , part of material aontai.nment and delivery systaaa 40 of ~°igure la. store dry. solid volumes of process materaal 25,.5 which are theca canveyed and metered by feed device 82 into corresponding smaller, heated chambers 8~ where melting anc, filtering occurs. Feed devico 82 might k~e of an auger or scr~:w feed device, although other feed devices are ps~ssa.ble, and i:~ driven by orator 83. The ensuing melted liquid media is pressurized by pressure devices 86, each of wh~.ch could be a pump or the like, prier to delivery via l.ic~uisl modia feed lines 88 to printh~:ad 2A or spray gua 30. ~ie~xid media feed lines 59 axe sh~~n w$th a break:, this i~s for clarity, as each of lines 88 conti~aue .from prevaur~e devices 8~ to either printbead 20 Or sprayex(s) ~~. depending open the line.
Thus. in addition to shapearendering, a systean according to the present inv~ntieara uniquely enables an abject tea be fabricated Wrath high resolution color features. Beneficiaries of this unique aspect include the medical, geolagical. arch~.taotural, and engineering fields, as well, as the arts. astronomy, and ~nat~y athar d.isciglines. Materials) 2° may be of different material colors or color cozr~inatioaas, ag weJ .1 as different material composition.
To achieve any desired level of visual ree.lisra, the colors cyan, TT°:.5119 - 12 --magenta, ye~.low, black, and ~ahi.te are preferred sisace any intermediate huc of the ful~ oo~.ca~c spectrum can b~ r~btain~m by material overlap or dithering.
Figure 3 is a perspective view of a maaroprocessos and a support removal system. according to a preferred embodiment of the present. invention. MiCropxocessc~r coxatrol syst90 and support removal system 95 are shown at a work stat~.on. Ahthough not shox~, such control. and support removal systems could be arrasaged differently and could be physically Goml~.ined wa.th the systems depicted in F'~.gures la oz 2a-~= to provide a ful~.y-automated rapid preatotyping system.
A ~ system is used to generate asd store specific data, including dimerasa.ons. color, or other desired properties, wh..ich simulate desired three-dimensional physical objects. This data is seat to. stored. and processed. by microprocessor control syste~a 9Q.
Mi,Croprocessor control sysr~eaa 9fl contains, microprocessor instructions, as well as image: processing and data conversion code to process the input data into sequential cross-sections of the three-d~ensional object to ba physically rendered.
The system, method, and process for computer-controlled manufacturing of desired three-dianensional objects involves da.spensiag layers of liquid materials ~5,~5 onto target suzf~CC SO
at predetermined locata.ons . These psed~ate~rcained locations are established by microprocessor caa~trol system 90 ~5ss~d ran the pr:oCessed slice data received froaa a computer image fa.le in tk~e CAL1 system. ~Iicropracessor control system 90 alse cantrols teas sequ~:nce and, timing of the syst~at, method, and process op~ratious as well. as the e7.ectzo-mechanical cdmponehtS f~r tn~tarial collv~~aI7lces f~~d~~C~. SeIBSOrs, c~Ad SystP~R1 prOGf.b"s~.'s.
rt should be realized that microprocessor control syst~ 90 could also encompass the GhD system, or any other desired object scanning and isaage capture device, ra~.l2ez than having this function performed Bay separate systems .
Suppoa~.' removal system 95 Cansists of rinse vat 96 of s~xfficiex~t size to fully .contain a v~lua~e of solvent and object 55 T~-15114 - I3 -F ~ lrn .,i~1 ~i7~ ;1 a i) v' r.~ zy on vrhich the .scalv~n~ gill ~~t. ~i~~ulati.on pusip or stirres° 9~
aQay be integrated to accelerate the da.ssolving process and carry away z~esidue. the solvent is watEar wheaa the moil anaateria.l ~5 to be se.~ov~ed is water soluble, etc.
Supp~reaaoval. system 95 could instead compxise temg~erature ehaa~ber 96 into which object 5.~ is placed. A.ir circulator 9~ y ialt~grated in such c~aam~aer 96 to accelerate the dissolving process . This latter systesa could be be;3t eseployed wheo, mold ~~:raal ~5 melts at a lower tennperature than object material 2S.
'this allows selecta.ve remozral of the mold when exp4aed to a temperature greater than the me3.tina~ point of the mold and .leas than the melting poiazt of the olaject. A Wade range of material 25.25 aombaanati.ons axe possiY~Ie such a,~ water aid wa~e~ was and glastic, plastic and metal. and so an. rn many cases mold and object materials 25,35 can be recyclet3 for repeated use, thereby reducing waste.
fa.c~re~ ~ is a process f low diagra~a depictine~ a process of maraufactura.zxg a three~dimensiunal object according to a preferred embodiment of the present invention. once the platform far the object is positioned onto the vacu~~rn fixture (clock 100), the printhead jets are checked tp see if they are all functioning.
'This is accomplished by positi,oniag printhead 20 so its autput is vi$wable to the optical inapectioa station (8lt~cl~ 110) . Thra printhead jets then print a patters of short line se~gm~xats (glocls 120) which are scanned to verify whether each of the jets .are f~xnctson3,ng properly (B3.ock 130) . If all. of the jets are determisied to not be operating properly, pririthead 20 is moved to the purge and wipe station (~lcck 150) where the syst~ a.s purged to unblocJc the flow of the je~a (Block 160). Printhead 20 is then returned to the optical inspection station (Block 110), where the jets are ag~ai.n checked (Blocks 120 and 130). Although it is not skaosaw in the process of figure 9, it should be appaxet~t that printhead 20 could be checked as, often as desired.
If all of the jets are o~eratiiag properly t~lock 140) , the ink supply is checked (Block 170): If the supply is found to be TT°1.5114 - 14 -r~~ ~~.~
inadeatB, t~l~ m~~.t cani8ter i,~ fi3.led ~~~~ 'tae 7aulk ca~~~t~r (Black 18Q) . Once the ink s~app3.y is suffiai.ent, the process coa~ti.nues by laadi,ng the c~l~ject' s sh.ce data (Block 190) .
The object's slice data ' s generated from a three-°e~isnensional.
cp~t~r "object" image incl.ncia~g color imfor~sativn is c~nverted key applicatioa software to a vertical sequence ~f tmo-dimensional pB~,~er~s. .~l.~.hough a second rage could be so~twaxe gemmeratet~ in the form ofr a negative va~lume around the first ianage, the '°mald's a,ge con~crt~d to a set of two-dimensional slices and the slice data of the object and mold l~la.eTi comba.ned in sec(ueaatial order, a ~eeond age is not necessary or preferred. The global action of sprayers 30 allow far aacur~Ate printing with only the object's ;,n~ge.
Once the first dace data i,s loaded (9lvak 190), platgoa-m 15 is positioned so cutting devices) 60 can plane it~t upper surface (Block 2I0) and platfoxmt 7.5 is lowered by one layer's thickness (black 220). Printhead 20 then scans and deposits the slice pattern according to the s.li.ce data received (Block 230) . The f~.xst layer's slice data detexatinew print head positipn above platform 1S along with appropriate ejeclGOr function at that location. Printhead 20 moves in a p3ane parallel to platform I5 until tt.es layer is complete. Once th~ printing of the first slice's pattern is completed. spray~rs 30 spray th~ upper surface og target surface 50 faith a unifc~°m layer of soluble support matdrial .35 (Block 240).
Although loading the next slice data is shown in the proc~ss flo~ac~aa.gt before the planing step, at can occur after the planing step or preferably, simultaneously with the pleasing step. In fact, microprocessor control system 90 may load the next slice data at any time during the print cycle when most expeda.tivus.
Tf this is not the last layer to be printed (Block 2S0), the ink supply is again checked ($lQCk 170) and inJc added if needed (Block 180). The next slie:e data is loaded (Black 190) w3xile p2atfox~ 15 is positioned sa cutting devices) 60 can plane the upper surface of target sugface 50 (Block 210) - Platform 15 is '~I-25114 - 15 ~-a f ° ~~ s~ 'wj ~
thin roved down~rard by rune layer thica~ne~~ (~hc9C 22Q) and ttae aaea~G
layer px~a.nted d~3ocks 230, 240) . Tf this is the 3.ast layer to be printed (Bloc% 250) , tkae paa~ a.s removed fry the vacuum fixture (~2ock 2S~) aatd iamztexsed in a solvent, preferably water, to di~~~lve t8~~ solt~le ~~pport nateria.l (lock 2?0~ . This process yields they completed three-dimensional object (~~.cc3s 2809 Ta an O~ta~p~,e cf preferred process aCCOxding to the present invention, liquid ~eax at 190 deg~° (material 25~ vs jet-printed in s~:~sa~n~ial l~y~r~ to foruc the abject pattern. Sims~ltaneouslyr seegueaxtial layers of ice (~nate:rial 35) are jet-pra,nted aro~d the Ql~~ect pattern to faacm a fro~e~x mold. The combined solid mass of materials 25, 3.5 is theca haa~.ed to melt the mold portiaa only.
lea~rirag a higx~ reso3.utionp recyclable casting pattern. Many other materials 25,35 cosibinations are passible, la.mited only by the imagination of those skilled ~.n the art.
Figure 5 depiots a pria~Ghead ~.nspeotioss and pureeing station according to a preferred emb~diment of the present invention.
Pxinthead 20 receives melted media via media feeder tube 3~.0 sad degasits dxop~ 320 of such media onto conveyor belt 330 i.n the form of short parallel lines 340. The su:cface of Conveyor laelt 330 is preferably made of paper. Optical sensor 350 scans parallex lines 340 printed by simultaneous operation of all pra,ntia~g de~wices or j~a~s 10 (net visible from t:~e dra~r~,ng9 of pri.nthead 20. The microprocessor responds to .any outpv~t of opta~Ga1 seansor 350 indicating at least one ma.lfur~ctiox~ing print device by directing psinthead 20 away from conveyer belt 330 to co~ap3.ete a puxge~-and-wipe for expulsion of any foreign ~znai~tsr. Air is forced into printhead 20 via purge valve-x~onatared air tube 36~. This effectively prxxges the f~reign matter from any raalfunctioniaag print device 10 on ptinthead 20. Pxinthead 20 is tlxen reaped off (raot shown) and repositioned ~ver corweyor belt 330. pr~.nthead 20 again deposits fresh media drops 320 onto conveyor belt.330 i~a the fcir~
of sizoxt parallel, lines 340 which are scanned by ~ptical seaasor 350. This procedure repeats until all print devices 10 on printhead 20 are properly functioning. A3thcugh an inspection Tz-ls~.i4 - z~ -_~1 c;a ~.
~y~~~an ~plcya,~tg a~ op~a,c~l ~~n~c~r ~~ dis~ass~d as pr~f~x~abh, various other inspection systems wall occur to those skilled ia~ the ~.rt .
figures ~a-b depict wav~fo,xm d~.~graans reflecting the oratput of optical sensor 350 a.ccoxdl.ng to a pxe~erred embt~tliment of the present invention. In these diagrams, square wavefcorsn.~ accurately show the number of jets functioning. The lack of a sguare wavefarm where there should be one indicates ~ malfunctioning jet. Figure 6a details t3ae output ~rom optical sensor 3~0 with all of tha bets ftanGi~ioning, while Figure ~b shows a waveform consonant with two bets anahfunc°ticaning.
Figures T~..c depict vie~rs of the result5.aag structure during process ste~a~ .230, 240. a.nd 210. r~spective~.ly, for manufact~ar~ of a three-d5.mensional object to be made of a low welting point material. such as wax, according to the preferred embodiment o~ the present invention of Figure 4. Figure 7a show9 printhead 20 depositing drops 920 of wax t_ca forx~ a Wax lay~r 400 at specific locations on soluble platform 15 as determined by the micro-processor coa~trol system accaxding tea the CAD image. Such lager 900. regardless a~ Gomposi.t.ion, is known. as the positive material and. when all layers are completed, will ~oaaa tho desired three-dimensional object.
In Figure 7b sprayer ~0 sprays droplats 430 of wa,t~r soluble m~ld anaterial 490 to encapsulate d~pe~siterl wane layer 900 rs9idiag on soluble platfoxzynn 410. ~9aterial 440, regardless of composition is knovrn as the negative material and, s~laen all, layers are completed, will fog the mold. A unique feature o~ Figure 4' s process is seen in figure 'b, naanely that thm sprayed negative material 490 is random. such that, spray particles ar~ not directEd by computer to specific x, y P~~irat~.
To prepare the surface for subsequent layers, a mill cutter or oth~r cutting dsvico(s) 60 vemoves s~me of the previous layer t,hiclsaess to expose the posative material 400. Fig,.are 7a depicts cutter 60 planing vaster soluble. mold material. 490 to expose deposa.~ced wax layer 400. This step also d~fines the thicken~ss of TI-1511.9 - lv -~;~ ;;:f ;.3 ~,' snob lay~rr and ~.e~mp~ns~t~as :.car dif3:erent .~.n.~'et die~p~a~ationo~s After all layers are processed, nes~ative material 440 is s~lactiv~xy reanovcd by sel~,rent, a~~t shown, l~av:~rag paa~,t~.v~
material 40~, wax in this case, intact.
Certain matOrials nay be tcw viacou~ to be u~~d i~ .~~kj~t type anechanisms. These materials may. however, exhibit desix~~ls propertiDS such ~~ dtaxility, appe~ran~e, gr ~A~.ubility in water.
~ desired ~ use for such viscous a~a.terial, intended only as an expl~ and not my way of lix~itationP might include circuit assemblies maa~ufactused from conductive.media sucxx as pastas and epoxies.
To utilize high melting point or high viscosity materials, atomizing nozzl~s and prossurized guns, such.as those used for painting, can be used as an alternative to ink~at type print4heads.
Sue:h nozzles or guns can employ pressuri2ed syringes ar piston-type action, and are ava~.lable with various nozzle diameters.
Fi~axes 8a-c depict views of the resulting stz°ucture dnxing process steps 2~0. 240, anal 210, respectively, fox manufacture of a three-dimensional object tc~ be made of a high melting point ar high viscosity maternal, aecording to the preferred eyabsdiment of the present ~.aveJntion of Fzgure 9. It is usd~rstood that such high melting point or high viscosity mate:eial can beg metal. ceramic, plastic, paste.. epoxy, eta. , as Well r~s a combi.xiation or alloy of such materials, such as tie-3.~:ad alloy as an examg~~.e and not by ~rxy of limitation.
Figure $a shows inkjet ~~ra.ntheadt 20 deg~osita.x~c~ drops 520 of wax to fog a wax layer 500 at specific locations on platfor~a 15 as ~3eteraas.r~ed by the microprocessor control system according tc~ the GAD image. Such layex 5(J0, regardless of comp~sitiono is the negative material arid, when all layess~ are comp~.eted, will form the m~ld or support. .
In Figure 8b sprayer nozzle or.gun 30 sprays droplets 530 of ha.gh felting point or high viscosity material 540 ovear the support material 500 and any pattexn cavities therein. P~aterial 590, regardless of composition i.s the positive material seed, when TI-x.5114 - 18 -compht~sd, with for~s the d~sici t%ar~~~~~~~.onal objet.
unique feature of Figuro 4~s ~roc~ss is scan in figure 8h, ly that the sprayed pasitive ~naterxal 540 is random, such that spray particles are not directed by computer to specific x.y Points.
fo prepare t3ae surface far saabses~ucnt layers, a mall cutter ear other device removes souse o~ tae previous layer thickxaess to erpase the positive material. Fi.c~ure $c depicts cutter 60 planing positive material 590 to exLoose deposited wax layer 500. tech layer is aaa.lled to a prescribed thickness which carnpensates for different nozz3.e dispensations. After all layers are pr~cesscd.
the fi~tal volv~e consists of a high melt-point or high viscosity object with a low melt°po~.nt mold. The ncgatiwe t~aterxal 500 is selectively removed by solvent or beat, not sh~s~n, leaving tl~e high melting point or high viscosity p~sitive m~mterzal 5~0 intact.
This approach is una~o in that it enables objects to be made of raa.a~y more a~ater~.als ~ such a.s nylon, Pt7~. or even metal alloys to naaue a few. which could not. be p~ssible using inkjet printer mcc~han~.su~s alone . Fuxthcrmor~:, milling the upper surface of deposited layers serves to relieve str~sss which. fox other systems.
causes part warpage. Also, the number of inkjet printh~ds required is reduced, since much of the material is sprayed randomly while providing sufficient braced area coverage, The simplicity of a cysteta. method, and process according to the preset invention offers many advx~ntages. Th~ printheada~ era small, inexpensive and can be confag~xred to ssvesa.l scan methods, including vector and raster. jector apertures are small. enahlisag very high. res~luti~rs. Furthea~utaxe, vride apertures or eject~r arrays can be utilized for high volume dispensing, as w~11 as dispensing of high viscosity taateria.ls . Additionally, a system, method. and Process aceordirq to the present invention ca~1 k~e tailored to va,riaus wade environments and applications ranging from foundries and machine shops to s~talZ desktop s~vgtems. because the Media can be printed oaa any surface, autamated conveyor and material handli..ng systems can be inc~rpdrated. This enables fast and continuous throughput from multiple data .sources. This '~I--1511. - 19 r ~~a~~
in~ludd~ m~l$i~l~ c t~r°~ge~~ratecl images, on at least one cs~at~puter, being rapidly protot,yped by a:xe os ~ac~re syst~as built accordi.a9 'to the teachings of this present invent;.on.
~o~se of the innuaaeramle oiajects which can be produced by this telrh~i.~tle include pr~tatypes. casting pattex°nsv molclav sc'~ip$tir~W
acd structural compoa~ents. Ir_ wfll quit%ly be apparent t~ th~se sk~7.~.~d in the apt that this 1 i.st is iaa no way caustiv~ aid that r~u:aer~~as other uses o~ the present invention ws.~.l occur to those sDca.lied in t~~ a~ .
It sh~uld he understood that carious emkaodi.mex~t,s of the invention can ~apsoy o= b~ P..mbQd3ad in hardware, software or microcoded firmware. Pxocess diagrams are also representativ~ of ~io~r d~.agr~na~ for r~io~ac~ded ~nei software based embodim~ts .
F~ur~thes. while a 5pecif3.c em.bodiaaexat of the invention has been shown said describcdv vari~aus modifications and alternate etttbod3raea~ts will occur to th~se s%illed in 'the art. Accordingly, a.~t is intended th~.~t the a,sa~recat=~.~n be limited only in terms of the appended claims .
Tl-15111 -~ 20 -

Claims (20)

I claim:~

1. A computer-controlled method for manufacturing of desired three-dimensional objects, comprising the steps of:
a. dispensing a layer of liquid, insoluble media onto a platform at predetermined locations, wherein said insoluble media hardens once so dispensed;
b. spraying a water soluble media to encapsulate said hardened insoluble media;
c. planing the uppermost surface of said water soluble encapsulant;
d. dispensing another layer of liquid insoluble media onto said planed surface;
e. repeating steps b-d until a predetermined three-dimensional object is formed: and f. removing said water soluble encapsulant to yield said desired three-dimensional object made of said insoluble media.

2. The process of Claim 1, wherein said step of planing further comprises the steps of:
g. removing a portion of the water soluble encapsulant: and h. exposing the underlying insoluble material for new pattern deposition.

3. The process of Claim 1, wherein said step of planing is followed by a stags of removing residue resulting from said planing step.

4. The process of Claim 1, wherein said predetermined locations are established by a microprocessor control system which receives. stores and processes data describing desired dimensions of said three-dimensional object, including color or other desired property data.

5. The process of Claim 1, wherein said platform is water soluble.

6. The process of Claim 1, wherein selected ones of said layers of liquids insoluble material are of a color different than the rest of said layers of liquid insoluble material.

7. The process of Claim 1, wherein selected ones of said predetermined locations within a single layer are of a color different than the rest of said predetermined locations within the same layer.

8. A process for producing a three dimensional object from computer-inputted data,comprising the steps of:
a. loading data about a first slice;
b. planing the uppermost surface of a platform;
c. dispensing a layer of liquid insoluble media onto said platform at predetermined locations established by said loaded first slice data, wherein said insoluble media hardens once so dispensed;
d. spraying a second media to encapsulate said hardened insoluble media;
e. loading data about a next slice;
f. planing the uppermost surface of said second media encapsulant;~
g. dispensing another layer of liquid insoluble media onto said planed encapsulant surface at predetermined locations established by said loaded next slice data;
h. repeating steps d-g intil a predetermined insoluble three-dimensional object within a second media mold is formed; and i. dissolving said mold thereby leaving said desired three-dimensional object intact.

9. The process of Claim 8, wherein said steps of planing further comprises the steps of:

j. removing a portion of said encapsulant:and k. exposing said underlying insoluble material for new pattern deposition.

10. The process of Claim 8, wherein said slice data comprises sufficient data to simulate an image generated by an object scan and image capture device, including dimensions, color, or other desired properties.

11. The process of Claim 8, wherein said second media is water soluble.~

12. The process of Claim 8, wherein said step of planing followed by a step of removing residue resulting from said planning step.

13. A system for manufacturing three-dimensional objects from computer data comprising:
a substantially planar target surfaces;
at least one eutectic material;
at least one water soluble material;
at least one microprocessor-controlled dispensing for repeated dispensing of said eutectic material in a liquid state onto said target surface at predetermined locations;~
at least one microprocessor-controlled spraying device for repeated global spraying of said water soluble material to encapsulate said eutectic material;
positioning devices to move said at least one dispensing device, said at least one spraying device, and said substantially planar target surface according to instructions received from said microprocessor;
at least one microprocessor-controlled cutting device for planing said encapsulated eutectic material to thereby prepare the surface to receive additional dispensing and spraying of said materials; and a support removal system for removing said target surface and said water soluable material, whereby said eutectic material remains intact.

14. The system of Claim 13, wherein said target surface is water soluble.

15. The system of Claim 13, wherein said at least one dispensing device is turned on or off according to a twa dimensional data map stored in a microprocessor.

16. The system of Claim 13, wherein said at least one eutectic material is two eutectic materials of the same composition but different colour.

17. The system of Claim 13, wherein said at least one eutectic material is two eutectic materials of different composition and different colour.

18. The system of Claim 13, wherein said at least one eutectic material is two eutectic materials of different composition but the same colour.

19. A method for manufacturing a three dimensional object comprising the steps of:
a) Dispensing a layer of liquid first media onto a platform at predetermined locations, wherein said media hardens once so dispensed:
b) Applying a second media to encapsulate said hardened first media:

c) Planing the outer-most surface of said object:
d) Dispensing a further layer of first media onto said planed surface;
e) Repeating steps (b) to (d) until a predetermined three dimensional object is formed; and f) Removing said encapsulant material.

20. A method as claimed in claim 19 wherein said removal of said encapsulant material is achieved by means of subjecting the object to a process by whick said first material is unaffected.