US2348871A - Sheet pulp container forming apparatus - Google Patents

Description

Mayflf, 1944 L. M. WILEY 2,348,871

SHEET PULP CONTAINER FORMING APPARATUS Filed Feb. l, 1940 4 Sheets-Sheet l Xlllll IHI INVENT OR.

May 15, 1944- L M. WILEY 2,348,871

SHEET PULP CONTAINER FORMING APPARATUS Filed Feb. l, 1940 4 Shees--Sheerl 2 Il. m

May 16, 1944- L. M. WILEY SHEET PULP CONTAINER FORMING APPARATUS 4 Sheets-Sheet 3 Filed Feb. l, 1940 INVENTOR. EE M. W/EK BY j V May 16, 1944- l.. M. WILEY 2,348,871

SHEET PULP CONTAINER FORMING APPARATUS Filed Feb. l, 1940 4 Sheets-'Sheet 4.

lNvENToR 526 EE f7, W/Lff Patented May 16, 1944 SHEET PULP FORMING Lee M. Wiley, Marlon, Ind., assignor of one-third to Jilllln T. Ict# and one-third to Reeley B. Wiley, both of Marlon, Ind.

Application February 1, 1940, sei-iai No. 316,142

(ci. iat-19) 12 Claims.

This invention relates to apparatus for fabricating relatively deep, seamless containers, or the like, from prime sheet pulp.

This application is a continuation-impart of the similarly entitled copending application, Serial No. 288,343, illed August 4, 1939.

This invention is directed primarily to the forming and finishing die structures.

The chief object of this invention is to improve the die structures of the aforesaid copending application, whereby improved containers may be fabricated.

One chief feature of this invention is the employment of a rubber-like die which is associated with its complementary die and the interposed pulp sheet material (or blank) so that a better article is formed and the same is accompanied by sheet stock ilow or migration as hereinaf ter pointed out.

Other objects and features will appear more fully hereinafter. It is to be understood that the aforesaid copending application illustrates, describes and claims a complete line production. Herein, only so much of the same will be included as is necessary for an understanding of the present invention.

The full nature of the invention will be understood from the accompanying drawings, the following description and claims:

In the drawings, Fig. l is a central sectional view through the blanking and initial forming die structure, the parts being illustrated in that position following blank cutting and initial deformation of the blank and immediately prior to the completion of the rst cup-like stage formation.

Fig. 2 is a central sectional view of the two complementary initial dies with the deformed sheet material therebetween and in the nal position of rst cup-like stage formation, the arrows indicating the pressure application for stock or material ilow.

Fig. 3 is a similar viewV of the second stage formation structure.

Fig. 4 is an elevational view of the preliminary finishing stage mechanism. portions being broken away to show the same and associated mechanism in central section.

Fig. 5 is a central section of the finished article in the final ilnishing mold and positioned for and immediately prior to ejection therefrom.

Fig. 6 is a central sectional view of the finished article.

Fig. 7 is an elevational view oi a modified form of the invention illustrating the first station formation, parts being broken away to show the same and other parts in section.

Fig. 8 is a similar view of said modification in v the second and third intermediate stations.

Fig. 9 is a similar view of said modification in the final nishing station.

Fig. 10 is a central sectional view of the article produced by the modification illustrated in Figs. 'I to 9 inclusive.

Figs. l1, 12, 13 and 14 are views similar and corresponding to Figs. 7, 8, 9 and 10 and of a third modification of the invention.

Fig. 15 is a face view of the blank groove forming plate. Y

Fig. 16 is a similar view of the cooperating plate portion of the tubular female die.

Fig. 17 is a sectional view thereof.

Fig. 18 is a perspective view of the finished article.

Fig. 19 is a transverse section thereof.

Reference is had to the aforesaid application for the detailed description and operation of the several parts of the common invention and the sequential operation thereof, it being understood that in general all which is disclosed therein is or may be incorporated with that speciilcally illustrated herein, hence the following comparison summary will be of value:

In Fig. 1 of the drawings hereof, there is illustrated structure and material corresponding more particularly to that illustrated in Fig. 8 of the copending application and the lefthand portion of Fig. 2.

In Fig. 3 of the drawings, there is similarly illustrated that which corresponds to the upper central portion of Fig. 2 of the copending application.

' In Fig. 4 of the drawings there is similarly illustrated that which corresponds to the lefthand portion of Fig. 4 of the copending application.

In Fig. 5 of thedrawings, there is similarly illustrated that which corresponds to the immediate rght-hand portion of Fig. 5 of the copending application.

In Fig. 1 of the drawings, 20 indicates the pulp sheet guide plate yieldingly constrained from member 2i as at 22 and guidingly secured as at 23 to member-2i. This plate is apertured atc/24 to seat tubular end 25 of initial female die 2G which mounts a sheet shearing member 21. The outwardly inclined face 28 of member 26 creasingly cooperates with formation 29. carried by plate 3l! in turn carried by member 3| for creasing the blank. A cooperating shearing member 32 is carried by member 30 for forming the blank.

Members 30 and 3| are apertured at 33 and 34 and slidable therein is stem 35. The interior of tubular portion 25 is uted to a lesser or greater degree, as desired, as at 36 and for the purposes described in the copending application. The extreme end of member 35 is recessed as at 31 and projecting outwardly and centrally therefrom is stem 38. Stem 38 is detachably supported by member 35 and has end 3S.

The stem 38 supports a rubber plunger die 40 having a ridge 4I at its forward end adjacent a recess 42. When not under constraint the rearwardly and outwardly directed wall is slightly dished as at 43. This rubber plug-like die from its maximum diameter tapers rearwardly, 'as shown at 44, and terminates in flat face 45.

The plug receiving die is indicated by numeral 46.A It includes an inwardly tapering recess 41, swelled outwardly as at 48 near the rounded outer edge 49. The inner end 50 of the bore 41 is recessed or grooved as at 5l. The central portion of this end is apertured at 52 and seated therein is tapered closure or valve 53 having stem 54 constrained toward open position by spring 55 and reference will be had to the aforesaid more fully hereinafter.

This valve structure is normally constrained toward the open position for the initial purpose of bleeding the air trapped in the female or receiving mold 46 when the article is forced therein by plunger 46 so that an air pocket does not result or occur in this mold 46, which would result in an irregular formation of the resulting article and the possible cracking or fracturing of the receiving mold, although, in view of the fact that the male die is of rubber, the latter probably would not occur, but the former would occur.

The operation is substantially similar to that set forth in the copending application. The sheet adjacent stripper plate is advanced in stepby-step movement when member 3l and member 35 are both retracted and spaced from the initial female die 26. Initial movement of member 3| toward this die shears at 21--32 a blankfrom the then stationary sheet and surface 29 begins a slow receding motion as stem 35 advances, to relieve the pressure on the preformed creases in the blank. Continued movement of member 3l, as aforesaid, causes member 30 with surface 29 to crease and dish the blank forming preformed creases therein. The surfaces 28 and 29 do not lock the blank therebetween but stop short thereof.

Stem 35 is then advanced and in so doing the end 4| of plug 40 engages the grooved dished blank and forces the blank through the grooved throat 36 of the female die structure until the blank discharges into the bore 41 of the female forming and receiving die 46. Continued forward movement of the plug initially forms the recess 60 and defining ridge 6I in the bottom of the resulting article. This force is indicated by arrows A and B in Fig. 2.

Continued movement of this stem in the same direction then swells the plug laterally and the pressure is applied successively and progressively to the side wall 62 of the article and as indicated by the force direction arrows C and D in Fig. 2.

In this forward movement, the tubular portion 31a enters flared mouth 49 of the female forming die 46 and advances into the latter preventing lateral escape of the plug material. The iinal pressure movement causes the rubber body portion 40 to deform and iill chamber 31, as shown in Fig. 2 and the forward end 31b of said member 35 serves as a back wall of the die arrangement to form the lip or outer edge 63 of the article, see Fig. 6. In this movement note that the stock is forced toward said edge; the direction of force being indicated by arrows E in Fig. 2. As indicated by all of said arrows and the arrows F, the entire body portion of the plug is now under pressure so that the entire article also is under pressure.

Note that the gap or annular space in Fig. l, between adjacent portions 48 and 43 of the female die 46 and plug 40, respectively, is not initially fully lled by the article material. This permits the stock to flow as it were from the bottom of the article and then under pressure toward the lip or upper edge thereof not then conned.

It will be noted that in the copending application the forming end of the plunger was shown and described as of solid metal and iluted around the outer surface to match the iluting in the gathering plate or tubular female die. In the present invention, the male plunger die is, preferably, of vulcanized rubber of about 55. hardness. This male die first draws the blank through the creasing arrangement and forces the blank into and through the tubular female die, as described, and then into the receivingor female mold 46.

In addition to the stock ow, as previously described, from the bottom of the article toward the top thereof, the liquid moisture in the stock is similarly caused to flow from the bottom of the molded article toward the top and the surplus is squeezed therefrom and drains out of the receiving mold 46 prior to the sealing of the mold by 31a and 36h, as shown in Fig. 2.

In addition to this distinction, it is to be observed that in the present invention, the face 31b of the wall 31a of the chamber 31 cooperates with the interior wall 41 of the receiving mold 46 and the forward or outer edge of the stock to rough form the resulting top edge 63 of the article as shown in Fig. 6.

It is furthermore to be observed that the normal shape of the rubber male die, when not under pressure, is substantially that illustrated in Fig. l and its final shape, when it has fully performed its function. is as illustrated in Fig. 2.

Note, also, lthat the upper side wall portion of the partially formed article in Fig. 1.appears thicker than the base. This is because of the predetermined wrinkle formation resulting from the cooperating arrangements. .Note, also, that in Fig. 2, this same wall portion is still thicker than the article base but not as thick as the corresponding portion in Fig. l because now the wrinkled stock has been compressed into a more solid wall.

Following article formation, as illustrated in Fig. 2, the plug is fully withdrawn from die 46 and the die 26 and then said plug and die 3l are completely retracted although stem 35 always is in so that sheet 20 may be fed across the blank shearing dies 32 and 21 for subsequent blank formation from the stock sheet. Then the cycle of operations previously described is repeated. Of course, it is to be understood that the stock may be treated as desired or required prior to blank formation and in that connection, reference is had to the aforesaid copending application for a better understanding of the pretreatment and handling of the sheet 20 and apparatus employed in connection therewith.

In Figs. 1 and 2, the die 46 is carried by a rotatable turret 56 through an intermediate portion 51 having an air pressure supply channel 58 terminating in chamber 59 which seats extension 46a of die 46, same being locked to member 51 by member 51b cooperating with inclined recess 46b, member 51h having a complementary inclined face 51a. Extension l46a is chambered at 46c and ported at 53a being controlled by valve 68. Chamber 46c communicates with supply passage 58 as by port 58a. Note that until sumcient pressure is supplied by passage 58, friction between the article and die will be greater than the force of spring 55 so that the article is not ejected or loosened in the die 46.

This pressure loosening, however, occurs following second, and third stage if employed, formation to which reference now will be had, it being understood that the turret 56 indexes after the plug 40 has been completely retracted from mold 46 and while, if desired, the blank is being cut from the sheet, all as is more fully described and basically illustrated in the copending application.

In Fig. 3 is illustrated the present embodiment of second and third stages of article formation. Whenever third stage formation is not required, the third station of the four stations of turret indexing is a blank or non-working station. The turret construction, et cetera, is more fully illustrated and described in said copending application and reference is had thereto and made a part hereof.

In Fig. 3, indicates the upper ram, 1I the upper mounting p1ate,secured thereto at 1Ia, 12 the plunger secured thereto at 12a and having central bore 13 to receive stem 15 of the punch 16. A retainer arrangement 11--18similar to that previously described secures these parts together. Slidably mounted on the punch is the edge forming collar 19 having tubular extension 19a receivable by the mold 46 as shown. Said collar is secured as at 80a to the lower mountng plate 80 secured as at Bla to the lower ram 8|. The terms upper and lower are used in a relative sense only.

It will be apparent that as the plunger 16 moves into the mold 46, it will further solidify the side wall of the article. Since the collar 19 is movable relative to the plunger, the upper edge may be formed by extension 19a either prior to, simultaneously with, or subsequent to wall compression and solidiflcation, as may be found desirable or required. a

It will be noted that the respective parts are centrally apertured and these register forming the passage 82, a flexible washer 83 being interposed between parts 12 and 16. The upper end of the passage 82 communicates with conduit 84 adapted, at theproper time, to supply pressure to said passage for a purpose to be specied later.

The lower end of punch 16 includes a tapered wall recess 85 and seatable therein is valve 86 having stern 81 slidably supported by guide 88 which cooperates with stop 89 on said stem to limit valve opening movement and valve escapement. Spring 81a normally constrains the valve to open position.

'I'his arrangement initially serves as an air bleed to permit the escape of air trapped and compressed in the article as the punch enters the same. Friction between the article and receiver mold 46 is normally insufficient to hold the article in the receiver mold 46 due to suction created when the punch 16 is withdrawn therefrom. Hence, air pressure is supplied to passage 82 when the punch is withdrawn which pressure positively insures retention of the article in the receiver mold upon punch withdrawal. This valve arrangement 86, as well as that previously described see valve 53, also has the function of permitting, before closing, the relieving of surplus liquid moisture in the article material.

After edge formation and lateral compression at the second and third turret stations, the receiver mold 46 with the article therein registers with the fourth station and when therein, air pressure supplied to passage 58 ejects the article from the receiver mold 46 tothe conveyor supported article support as shown in the central portion of Fig. 2 of the copending application. This conveyor then carries the article through the drier shown more particularly in Fig. 3 of said application. After removal therefrom, the conveyor discharges the article to a cup type receiver, as shown more particularly in the righthand portion of said Fig. 3, of said application which receiver is conveyor supported.

Reference will now be had to Fig. 4 hereof. Herein, 99 indicates the conveyor cross rails spaced sufliciently apart to receive the cross member 9| secured thereto as at 90a. Said cross member includes a tubular depending skirt 9m dening an opening in which is seated a nishing receiver mold 92, the midportion of which is reenforced by said skirt. 'Ihis mold is rigidly secured to the cross member as by welding, and the like as illustrated in Fig. 4.

When the conveyor positions this receiver mold 92 with the article therein, in the nishing press, the mold bears on the bed plate 93 thereof. Such a nishing press, is shown most clearly in the left-hand portion of Fig. 4 of the aforesaid application. The essential parts of the finishing male or plunger die or punch thereof, see Fig. 4, are substantially similar to that illustrated in Fig. 3 hereof, 94 indicating the upper structure and 95 the lower structure. The former supports punch 96 while the latter supports nishing ring 91.

This structure is similarly provided with passage 98 which communicates with ducts 99 at the lower end of the punch to relieve the trapped air as the punch enters the article, and to apply pressure to the article when the punch is with- `drawn to hold the article in the receiver die 92.

The ring 91 seats in the upper end of this. die for upper edge The receiver mold 92 at the bottom is vented as at |09. This is to permit the article, when supplied to the mold, to settle and seat therein. Were it not for these ducts, the article, upon entering the mold, would trap the air therein and the same would prevent proper seating of the article in said mold 92.

'I'he article, after passing through the nishing press, may be dried or cured, as illustrated in the right-hand portion of Fig. 4 of the copending application, and thereafter handled, as shown in Fig. 5 thereof or as otherwise desired and described in said application.

Referring to Fig. 5 hereof, there is herein illustrated an air pressureembodiment of an ejector device. The finishing receiver mold 92, with the article therein is carried tothe discharge station and when inverted, as shown, the article due to friction normally will not discharge from the mold.

Inasmuch as the conveyor has intermittent movement required for finishing operations, see Fig. 4, there is provided at said discharge station, a vertically movable plunger structure, vertically movable in timed relation to conveyor movement by means not shown. When the mold is stationary, this plunger structure contacts same, ejects the article therefrom and then elevates so the empty mold can freely return to the article loading station for a semi-ilnished article, all as previously described in the copending application.

Herein, the elector structure includes an air pressure supply and support member M having air supply passage N therein and to the lower end of which is secured the head O having chamber P therein. In said chamber is mounted a resilient (rubber) contact head projecting laterally and downwardly therefrom and said resilient head is of ring formation having 4passage R therethrough.

When the structure engages the base of mold 92, iiange Q' enlarges laterally both inwardly and outwardly and ports in said mold 92, then can transmit the pressure, when supplied by passage N, to the mold interior for article ejection. 1 Fig, 6 illustrates the finished article formed as above described and the portions thereof are indicated by numerals previously mentioned. This article is a deep drawn seamless nbre cup with a smooth upper edge.

Reference will now be had to Figs. 7 to 10, inclusive, wherein a modified form of the invention is illustrated. Numerals of the primary series, increased by |00 herein, indicate -like or similar parts previously illustrated in Figs. 1 to 6, inclusive, and designated by the primary series.

The article shown in Fig. 10 includes the upper outwardly directed curled edge |63. This is the only difference from the straight edge article shown in Fig. 6. In Fig. '1, note that the punch |40, face |311) and edge |49 of receiver mold |46 cooperate to form the outwardly directed rim |63 of the article.

In Fig. 8, the subsequent forming die ring I 19a, the punch |16 and the portion |49 of receiver mold |46 cooperate to fully compress the article mouth and'rim |03, as shown, the end |191 of the ring Visa being properly shaped for such cooperative formation and for shearing surplus stock from the rim |63.

In Fig. 9, the receiver mold |92 has its upper end suitably formed to cooperate with the complementarily formed punch 96 and finishing ring |91, and interior face Isla to nish form the article shown in Fig, 10.

In like manner, numerals of the two hundred series in Figs. 11 to 14 indicate corresponding or like parts. In this embodiment of the inver.- tion, note the edge 263 is of greater thickness than the body portion of the article to form a multiple thickness edged cup. This edge 263, as herein illustrated, is a compaction of the stock, rather than a folding over of the stock and subsequent compression or compaction of the folded portions, which, of course, is quite feasible and obvious herefrom after there is disclosed the formation of rim |53.

Whenever desired, although herein illustrated as of integral character, any die member, male or female, may be of unitary character, special hardened inserts being provided as illustrated in Fig. 8 and indicated by numeral |49.

For simplicity, the complete disclosure of the aforesaid application is omitted herefrom but the same is made a part hereof insofar as the same is necessary to effect an understanding of this invention.

Inasmuch as herein, as well as in the copending application, nowhere it is disclosed that any pair of dies have or require relative rotation, it is quite obvious that non-circular cross-sectioned sidewall articles may be formed with equal faculty.

Illustrative thereof there is, in Figs. 15 to 19, inclusive, illustrated another modification of the invention. Numerals of the three hundred series indicate like or corresponding parts. Herein, see Figs. 18 and 19, the article is of the straight upper edge type. It may be of other character, such as the curled or multi-thickness type. as illustrated in Figs. 10 and 14 respectively.

Herein, in Figs. 15 to 17, inclusive, there is illustrated a groove preforming arrangement as applied to a non-circular outlined article. Of course, the shearing dies, receiver mold, rubber plunger, supporting structure, intermediate forming dies, conveyor supported receiving mold and finishing dies, and such dies including plungers and rings would be shaped, as required, to accord with the finished product.

Hence, since the changes in the last mentioned are one of outline and configuration only, for simplicity, only certain of the radically modified elements are illustrated, see Figs. 15 to 17. Note that the cooperating die grooving plate faces have omitted therefrom sonie of the radially directed grooving formations, such omissions occurring where the article sidewall is to be smooth and coplanar, and whether tapered or otherwise. Note the groove forming arrangements are localized more particularly at the corners and radiate therefrom.

In all other respects, the article illustrated in Figs. 18 and 19 is producedby appropriate means shaped to conform to said article and the aforesaid modiiication of the initial pre-grooving die arrangement, as previously described. The article herein has rounded corners, see Figs. 18 and 19, between flat sidewall faces. These faces, if desired, may be iluted from ornamentation and the like. Such a fluted container would be used for jellies of all kinds so that when released from the container, a corresponding ornamented surface of the jellied mass would result.

In this latter instance, the faces of the confronting groove forming die members would have the non-grooving portions appropriately grooved and the grooves formed thereby, and not the corner grooves, would be carried through succeeding dies, plungers and molds and accentuated in the article formation.

It has been ascertained that when the prime pulp sheet has been plasticized with a solution of plastic (Ternite and acetone) the bleached kraft stock when in container formation has a marked similarity to artificial ivory, ivory colored Celluloid or ivory colored plastic. This container resembles a similar one, but has greater strength than such a one wherein the pulp sheet has been moistened with a very dilute solution consisting of one part starch to about one hundred and forty parts of water. Even this starched container has a pseudo Celluloid appearance and some of the characteristics thereof.

The foregoing illustrations are recited by way of example only, since other materials may be employed whenever desired or required. Of course, it is to be understood that whenever desired or required the molds and dies, particularly if of metal, may be heated, as by included resistances. Such may be necessary with certain impregnating mediums. However, the inclusion of such heating arrangements is so well known in the paper products industry that an illustration thereof has been intentionally omitted.

While the invention in this and the copending application hasvbeen described as applied to the production of a container and the like for foods and packaged edibles, it is quite obvious that the articles thus formed need not be restricted to such use. For example, the article shown in Figs. 18 and 19 could be formed of heavier stock and properly plasticized with an electrical insulating material such as Japan lacquer or the like and have an outwardly directed flange somewhat similar to but wider faced than flange 363. Such an article so anged forms a capable and satisfactory outlet box, for electrical wall switches, fixtures and the like. This single reference is given by way of example only since it is only one of a myriad of .forms that might be so fabricated and used for other than food packaging purposes. Some of such industrial uses, in addition to that mentioned herein, are referred in the copending application.

While the invention has been illustrated and described in great detail in the foregoing description, the same is to be considered as illustrative and not restrictive in character.

'I'he several modifications described herein, as well as others which will readily suggest themselves to persons skilled in this art, all are considered to be within the broad scope of the invention, reference being had to the appended claims.

The invention claimed is:

1. In a container forming machine a receiver mold, a rubber-like plunger for nesting, and compressing when nested therein, a blank, said plunger normally being of smaller maximum peripheral outline than that of the maximum interior outline of the mold, and a single means movable in timed relation with plunger for the cooperation mold and confining and deforming the plunger for conforming the nested blank to the mold interior, the plunger being axially elongated and of greater length than the resulting container, said means being of chambered character, the chamber confronting the mold receiving end, the plunger body being receivable by the chamber upon deformation of the plunger in the mold incident to blank formation.

2. In a container forming machine, the combination of a. receiver mold for a fibrous container adapted to nest therein, said mold being ported to relieve air trapped therein to permit such container nesting, a punch receivable thereby, means operatively associated with the open end of the mold and having telescopic association with the punch for container confinement when compressed by said punch, said punch being ported to relieve air trapped in the container upon punch entrance thereto, and a conveyor arrangement and a bed plate, the bottom of said mold having operative bearing on the bed plate and the conveyor having means supporting said mold thereabove.

3. In a container forming machine, the combination of a receiver mold for a fibrous container adapted to nest therein, said mold being ported to relieve air trapped therein to permit such container nesting, a punch receivable thereby. means operatively associated with the open end of the mold and having telescopic association with the punch for container confinement when compressed by said punch, said punch being ported to relieve air trapped in the container upon punch entrance thereto, and a conveyor arrangement and a bed plate, the bottom of said mold having operative bearing on the bed plate and the conveyor having means supporting said mold thereabove, said means being of elongated tubular character for mold nesting and reenforcement.

4. In combination a conveyor, an article containing mold supported and movable thereby, and a pressure ejector structure movable transversely of conveyor movement for mold contact and disengagement, said mold at its closed end being apertured, said structure including a resilient mold engaging portion and arranged to supply pressure, said portion sealing the contact connection between structure and mold for pressure ejection of the article from the mold.

5. A structure as defined by claim 1, characterized by the means including a central projection extending through the chamber and projecting therefrom and supporting said plunger, the chamber end of the plunger being movable toward the peripheral and back wall of the chamber in the blank compressing and mold seating movement of the plunger.

6. In a fibre stock container forming machine a cup-shaped receiver mold, a tubular die having its discharge end juxtapositioned to the mouth of the receiver mold, a plunger die of rubber-like material movable through the tubular die and into the cup-shaped receiver mold, and centrally apertured complementary creasing means at the intake end of the tubular die for creasing a blank. a portion of said means being movable toward and away from another portion thereof, the portions when separated nesting the plunger to permit blank interpositioning between the portions, the plunger moving therefrom and relative thereto, subsequent to creasing action by the creasing means upon the blank. and into the die tubularity for drawing the creased blank from between the creasing means portions and through the tubular die for forming a grooved sidewall in the blank and for seating the precreased and grooved side wall including blank in the cup-shaped receiver mold, the side wall of the plunger being similar but not conforming to the interior of the receiver mold to facilitate the seating of the precreased and grooved side wall blank therein, additional plunger movement in the direction of the receiver mold simultaneously deforming the plunger to receiver mold interior conformation for compression of and deformation of the grooved wall blank to receiver mold interior conformation.

'1. A fibre stock container forming machine as defined by claim 6 wherein the tubular die is interiorly corrugated, the corrugations extending longitudinally thereof and being juxtapositioned to the said other portion of the creasing means whereby the blank creases in blank drawing through the tubular die cooperate with the plunger and tubular die to prefold the creased blank stock into a grooved sidewall formation.

8. A fibre stock container forming machine as defined by claim 6 wherein there is provided a chambered support for the plunger die means, the latter projecting therefrom and toward the receiver mold, the chamber being formed by means providing an open face closest to mold and projecting from the support, said last mentioned means and the open end of the receiver mold having telescopic association when the plunger die is seated therein for stock and die retention to insure stock and plunger die deformation and conformance to the mold interior.

9. A fibre stock container forming machine including in combination a receiver mold having one end closed and the opposite end open, the open end being of greater cross-sectional area than the closed end. a rubber-like plunger having an exterior surface similar to but not conforming to the mold interior and movable into and out of the mold, all dimensions of the plunger, except that of axial length, being smaller than the correspending mold cavity dimensions, the plunger, when initially seated in the mold, with a cupshaped blank therebetween, normally projecting beyond the open end of the mold, the cup-shaped blank having a length less than the mold and the plunger and a bottom and side wall formation initially similar to that of the plunger and mold cavity, chamber-like means cooperating with the open end of the mold adapted to close the cavity, and means for advancing the last mentioned means and the plunger for initial closing of the cavity and plunger connement therein, additional advance deforming said plunger to receiver mold cavity conformance and chamber illling for pressure deformation and distribution of the stock of the cup-shaped article in the closed cavity, initial return movement of the last mentioned means opening the cavity and permitting the plunger to assume its initial unconfined formation for plunger release from the cup-shaped article and the mold cavity and withdrawal of the plunger therefrom.

10. In a container forming machine, the combination of a receiver mold for a iibrous container adapted to nest therein, said mold having a port to permit escape of air therefrom in container nesting, a punch adapted to enter said mold, means operatively associated with the open end of the mold for closing same with a nested container therein, said means having a Vclose telescopic association with said punch at all times and cooperating therewith to form the open end of the container, said punch having a port to relieve air trapped in the container upon punch entrance into the container, mechanism for applying said means to the mold prior to punchcontainer engagement, means operable to supply pneumatic pressure through the punch port to retain the container in the mold upon punch separation therefrom and irst mentioned means separation from the open end of the mold, and other means operable thereafter to supply pneumatic pressure through the mold port to the container to eiect release of the latter from the mold upon punch and first mentioned means separation therefrom.

11. In a container forming machine, the combination of a receiver mold member for a fibrous container adapted to nest therein, said member having a port to permit escape of air therefrom in container nesting, a punch member adapted to enter said mold member, means operatively associated with the open end of the mold member for closing same with a nested container therein, said means having a close telescopic association with said punch member at all times and cooperating therewith to form the open end of the container, said punch member having a port to relieve air trapped in the container upon punch member entrance into the container, mechanism for applying said means to said mold member prior to punch member-container engagement, means operable to supply pneumatic pressure through one port to the container to retain same in operative relation with the member containing the other port in the separation of said members, and other means operable thereafter to supply pneumatic pressure through the other port to the container to effect container release following separation of the members.

12. A container forming machine, as dened by claim 11, wherein said punch member, the open end of said mold member, and said iirst mentioned means have cooperating portions enlarging laterally and externally the edge oi' the container into a curled formation. and other cooperating means on said mold member and rst mentioned means for trimming the curled edge of the container.

LEE M. WILEY.

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