US2718661A

US2718661A - Film extrusion apparatus

Info

Publication number: US2718661A
Application number: US267840A
Authority: US
Inventors: Arthur O Russell
Original assignee: American Viscose Corp
Current assignee: Akzo Nobel UK PLC
Priority date: 1952-01-23
Filing date: 1952-01-23
Publication date: 1955-09-27
Anticipated expiration: 1972-09-27

Description

P 7, 1955 A. o. RUSSELL FILM EXTRUSION APPARATUS 2 Sheets-Sheet 1 Filed Jan. 23, 1952 t R Kw s Nm Q N wf N QM @N N A A m\ l R NM ya 0 m mN Q R a w w n hhw m Mm vn INVENTOR. ARTHUR O. RUSSELL Q T; iii; 1:

F: C E C p 27, 1955 A. o. RUSSELL 2,718,661

FILM EXTRUSION APPARATUS Filed Jan. 25, 1952 2 Sheets-Sheet 2 United States Patet1f FEM EXTRUSION APPARA US.

Arthur-l0. Russell, Fredericksburg va assignor to American Viscose Corporatiomtwilmington, -Del'.,: a corpo- -t ration of Delaware pp on u y Z,. ria! ND-.2.67,840

7 Claims. (Cl. 18-:-:-15) .1

This invention relates toapparatus for producing non;v

fibrous foils, pellicles filrns,r,,sheetsv and like products from film-forming compositiens. v More particularly it H relates to an improved\extrusiondevice whichprovides greater adjustability and control of. the ultin atei thick ness of the extruded film..

The manufacture of films, foils and likeproductsis m y c r u i by X rud ng.,i o-a c agulat n or regenerating bath a film-forming substance such as viscose from a receptacle or hopper which is provided with slightly separated lips that define an elongated oridemands of production often require that the width ofthe orifice amount to only a fraction ofarnillj neter.

Although various previous improvements have. been sug-... gested to overcomethisdifiiculty theyhave .beenshown unable to provide suflicient accuracy in controlling. the,

required dimensions of the orifice. s

It is a principal object of this invention to provide,

novel and improved film extrusion apparatus wherein,

the dimensions of the elongatedextrusion.orificeamay be quickly and accurately adjusted...

It is a further object of this. invention toconveniently,..

position the extrusion orifice adjusting means suchtthatt it may be easily reached and-manipulated.

Referring .now more particularly tozFigures 1,,2 and.3 of. .the .drawing, the spinninghead assembly 3.,is rotat-. ably mounted by means of the tubulantrunnions 6 in the. journals v,4 whichare positioned at opposite ends of the coagulating \vessel or..container 5.. The hand. wheel; 7 in, ,Fig ure.1 .of the, drawing. provides a convenient means for rotatably .adjusting..,thev position .of-.the..spin-.. niug assembly. in the .journals..4 to control the angular-- disposition of the spinning ,orifice in the.coagulating-1. vessel .or chamber .and.;toinver.t the assembly .forzthe inspection .and maintenance thereof.

The. spinning assembly 3.,comprises a pair ofelongated. U-shaped channel members. .8 .and ,9 which are fastened, back to back by, the bolts \10. Cover plates 11 andZ'L extend .acrossthe opensides andsends. respectively.,of thephanrrelv

members

8 and 9 and:providebetweenwuit: able, inlet-and discharge means not shown ;in, .the. drawing the elongated, enclosedchambers 12 .and. 13 through... which may I flow a temperature regulating. medium -such aslwater steam or air.. The lower portions of the .abutting channel. members 8rand 9 are preferably recessed. as shown 1 in the, drawing to form the. channel. 26.. .therebetween but;.it,is,to be understood that.the..channel may beformed; in any convenient other way such as by insert-. r ing-a shim 1 between, theupper portions. of the abutting chann lm mb r Carried. ,.on. th ejunderside..of the. channel members 8 .v and) are the, adjustable .lip .members ,14 and. 15 which. determine the .width of theextrusionnorificer Eachof the rlip membersv includes in.,cross-sec tion. .a lip proper. 41 which is. formed. integrally. .with a horizontal .fiange, or,-,extensi on at an angle thereto. As shown in Figures 5 and,.6,. the. extension lies in a horizontal plane hflffias ,thelip. proper 41;;extends downwardly.- and, obliquely. The extension .40.-of lip member 14 is fas-.

. tenedto the, lowensurface, of bearing plate .16 .andchan- Other objects and advantages of the invention will be-..;.

come apparent from a description of .the of the invention.

by providing a pair of independent adjustingmeans; for

embodiments 1 each extrusion orifice.- The first .adjusting. meanS.-:P 9-. vides a coarse control of the width of. the: orifice ,by

slidably adjusting the position :of;.the entire. lip member The second adjusting means, provides a more delicate adjustment of the orifice dimension .by means of. a flexing action of a lip member.

In the accompanying drawing which is illustrative ofz the invention,

Figure 1 is a front. view of a spinningheadassembly wherein there is disclosedan improved extrusion lip v adjusting means which is designed in accordance. with a vview f t mprpv d .spinninglgeadm Figure 4 is a cross-sectional view of a modifie'tl spinning head assembly which is designed in'accordance .with a second embodiment of the invention;

Figure 5 isan enlarged fragmentary view similar, to

Figure 2 showing the adjustable lip member in a sub-1 stantially closed position; and

Figure 6 is a view similar to Figure S in'which; the

adjustment achieved has been'illustrated in a somewhat;-

exaggerated manner.

nel r r1e m,ber,. 8 ,by; a plurality ofupwardly. extending. ,cap,. screws 17 which,;are located along; each of. its:elong-ated,. edges. The, extens.ion-.40 ,of the .lip..member-,15 .isifas. tened to, itsrespective-channel members 9 by a pluralityv I of cap screws 19, whichrextend upwardly. through .a pinrality of slots 18, in. the .lip member, through .the assowciated bearingplate 20; and threadedly engage the under: I side;p .,the channel. member.; The .slots 18 .in .the lip member 15 permit-a transverse sliding adjustment ofthe lip;,member as will ,bedescribed more fully, hereinaften.

The opposed .angularlips -41,.0f the..rorificertdefining lip mfimbersnfi and ,.15 ,are alined, with .channel'lti,v formed between

thechannel members

8 and 9 and- :are preferably tapered downwardly. toward the extrusion ori-r: fice Thegupper boundary. or .walhof the channel 26. between the,

channel members

8 and 9 is also preferably tapereddownwardly. fromthe end. of the spinning. assem-- bly at which the, spinning. solution is supplied toward the opposite end, thereof.. Supporting .blocks. -28.:arebolted to the lowenp'ortion ofeach endaof the channels members- .and extend downwardly therefrom. Each Of the supporting; blocks carries. thetbolt means ,29ga1'ld' 30: for removably .clamping .the- .end. plates. 31.v across; the. end extrerrnjties of .the, opposing orifice defining 1ips Thus, it is seen that the spinning,solutionwmay progress-1 from its source not; shown .on the-drawing through; the tubular trunnion'fi ,along the grooved-portion between the channel rnembers .and downwardly through therelon-a atedp ifii e i to the-coag b Each of the

lip m bers

14, and 15 is;designedv. such that it can be independently adjusted .to .control .-@the dimensions of the extrusionorifice. Lip,member.15..may,. be slidably positioned in slots 18 .on cap ,screwst19. by, means of the adjusting screws 21 -.whichr.,threadedly.en; gage the end. of extension 40 and extend eut dl therefrom: Supporting bracket member 32 which extends outwardly and downwardly from the cover plate 11 guides each adjusting screw in slots 33 and cooperates with the

adjustable nuts

34 and 35 on the adjusting screws to control the position of the lip member on cap screws 19. This sliding adjustment of lip member 15 readily permits a preliminary coarse adjustment of the orifice dimensions.

The dimensions of the orifice may also be controlled by varying the position of lip member 14. The means which has been devised for controlling the adjustability of lip member 14 includes a plurality of adjusting screws 23 which are fastened along the center of the extension of the elongated lip member and extend upwardly therefrom through the legs of the channel member 8. Supporting bracket member 36 which is mounted on the upper surface of channel member 8 guides the upper portion of the adjusting screws in apertures 37 and cooperates with the

adjustable nuts

38 and 39 on the adjusting screws to control the position of the lip proper 41. Thus, variations in the setting of adjusting screw 23 cause a bowing action within the elastic limit of the metal in the mounting portion of the relatively flexible extension between the cap screws 17 and the angular portion simultaneously flexes toward or away from the opposing lip member 15. The adjustment described above results from a bending or flexing of the lip along a minor or transverse axis thereof as opposed to a flexing longitudinally or along the major axis. It has been found that control of this type of flexing action in the lip member provides a very accurate means for making minute adjustments in the width of the orifice. The upper surface of the lip member 14 is preferably undercut at 24 between the axes of the cap screws 17 to provide greater flexibility of the lip member and a greater range of adjustability of the orifice dimensions.

An additional feature of the novel and improved orifice adjusting means of the present invention is to be noted in the ready accessibility of the adjusting means in its conveniently exposed location.

Referring next to Figure 4 of the drawing a second embodiment of the invention is disclosed wherein a pair of adjustably controlled orifices permit the simultaneous extrusion of a like number of non-fibrous films. In this embodiment of the invention the spinning head assembly is divided into two separate chambers and 51 by a downwardly extending inverted Y-shaped partition member 52. The lower portion 61 of the legs of the Y partition form a fixed lip member for each of the extrusion orifices. The opposing lip member 63 of each of the orifices is adjustably mounted by means of the cap screws 54 upon elongated U-shaped channel members 58 which are fastened to the upper portion of the partition member 52 by means of bolts 59. Each of the lip members 63 includes in cross-section a mounting portion and an orifice-defining angular portion which extends downwardly therefrom. The open sides and ends of the channel members are preferably respectively closed by the side plates 53 and end plates not shown in the drawing thereby providing elongated chambers through which a temperature regulating medium may flow as described in the previously described embodiment. As in the previously described embodiment the opposed surfaces of the orifice defining lip members 63, 63 are alined with the chambers 50 and 51 and are preferably tapered downwardly toward the extrusion orifice.

Each of the movable lip members 63 may be slidably positionable in slots on cap screws 54 by means of the adjusting screw 55 which threadedly engages the end of the mounting portion of lip member 63 and extends outwardly therefrom. Supporting bracket member 69 which extends outwardly from the cover plate 53 guides each adjusting screw in slots 70 and cooperates with the adjustable nuts 71 and 72 on the adjusting screws to control the position of the lip member on cap screws 54. This sliding means permits a preliminary coarse 4 adjustment of the width of each of the orifices. The elongated adjusting screws 57 provide an additional means for varying and controlling the dimensions of the orifice. The elongated adjusting screws are fastened to the center of the mounting portion of each of the elongated lip members 63 between the bolts 54 and extend upwardly therefrom through the legs of channel member 58. Supporting brackets 73 which are mounted on the upper surfaces of channel members 58 guide the upper portion of the adjusting screws in apertures 74 and cooperate with the adjustable nuts 75 and 76 on the adjusting screw to control the position of the lip member. Thus, variations in the setting of the adjusting screw 57 cause a bowing action in the mounting portion of the relatively flexible lip members 63 between the bolts 44 and the angular portion simultaneously flexes toward or away from the corresponding fixed lip member 61. As in the previously disclosed embodiment the upper surface of the lip member is preferably undercut as at 77 to provide greater flexibility of the lip member and a greater range of adjustability of the width of the orifice.

While preferred embodiments of the invention have been described, the description is intended to be illustrative only and it is to be understood that changes and variations may be made without departing from the spirit and scope of the invention as defined by the appended claims.

I claim:

1. Apparatus for defining and controlling the width of an extrusion orifice comprising a pair of opposed lip members, an integrally formed oblique extension on at least one of said lip members, and means for lowering said extension in a transverse plane to control the width of the orifice.

2. Film extrusion apparatus comprising a spinning head assembly having an elongated opening therein, at least one lip secured to the spinning head having a flange extending longitudinally of the spinning head and obliquely to the lip, and means for bending the flange to pivot the lip and thereby control the width of said opening.

3. Film extrusion apparatus comprising a spinning head assembly having an elongated opening therein, at least one lip secured to the spinning head having a flange extending longitudinally of the spinning head and obliquely to the lip, at least one adjusting screw extending through the spinning head and connected to said flange approximately at its center, and means for applying pressure to said screw to flex the flange to adjust the width of the opening.

4. Film extrusion apparatus comprising a spinning head assembly having an elongated opening therein, a pair of opposed orifice defining lip members positioned on the assembly and which partially extend across the width of the opening, a lip proper formed along at least one of the lip members, at least one of the lip members having a flange extending substantially at right angles to said lip proper, and means for bending said flange to adjust the Width of the orifice.

5. Apparatus in accordance with claim 4 having a plurality of bolts extending through the head along the length of the flange.

6. Film extrusion apparatus comprising a spinning head assembly having an elongated opening therein, a pair of L-shaped lip members secured to said spinning head, said members having a substantially horizontal extension and a lip proper formed integrally and obliquely therewith, the outer edges of said lips being positioned in close spaced relationship to form an extrusion orifice therebetween, and means for bending the extension of one of said lip members to closely control the width of said orifice.

7. Film extrusion apparatus comprising a spinning head assembly having an elongated opening therein, an L- shaped lip member extending longitudinally of the spinning head, a first fulcrumed edge along the backface of the lip member, a second fulcrumed edge extending along the backface of the lip member in spaced transverse relation to said first edge, and means for bending the lip member between said fulcrums to pivot the outer edge of 5 the lip through an are centered substantially at one fulcrum.

References Cited in the file of this patent UNITED STATES PATENTS Kinsella et al. Jan. 7, Crane et a1 June 15, Fordyce Sept. 8, Fordyce et a1. Sept. 8,

Bailey et a1. Aug. 23,