Method of and apparatus for producing paper cups

Oct. 1, 1940. f. p. swallow et al 2,216,331

METHOD OF AND APPARATUS FOR PRODUCING PAPER CUPS

Filed Oct. 28, 1938 2 Sheets-Sheet 1

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Fkcdrjck C. Smith

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Oct 1, 1940. f. p. swallow et al 2,216,331

METHOD OF AND APPARATUS FOR PRODUCING PAPER-CUPS

Filed Oct. 28, 1938 2 Sheets-Sheet 2

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Patented. Oct. 1, 1940

2,216,331

UNITED STATES PATENT OFFICE

2,216,331

METHOD OF AND APPARATUS FOR PRODUCING PAPER CUPS

Francis P. Swallow and Fredrick C. Smith, Worcester, Mass., assignors to United States Envelope Company, Springfield, Mass., a corporation of Maine

Application October 28,1938, Serial No. 237,536

Claims.

The present invention relates to the manufacture of paper drinking cups, of the type comprising a tubular sleeve-like body and a separately formed, disk-like bottom portion located within ⁰ the body and adhesively secured to the body wall at one end, to provide a water-tight closure for the cup.

The object of the present' invention is to provide an improved method of and apparatus for producing cups of the above indicated character, the invention being particularly concerned with the attachment of a bottom disk to a cup sleeve, in such a manner that an extremely close waterj, tight junction is obtained between the cup parts. The above and other advantageous features of the invention will hereinafter more fully appear from the following description, considered in connection with the accompanying drawings, in „„ which: ΟΛ

Fig. 1 is a diagrammatic view, showing the general relation that exists between various steps in the formation of a cup, in accordance with the invention.

Fig. 2 is a diagrammatic plan view, illustrating the cup forming operations indicated in Fig. 1.

Fig. 3 is a vertical sectional view of a mechanism for producing cup bottoms and, delivering them to a cup forming station.

„_n Fig. 4 is a horizontal sectional view along the ^υ line 4—4 of Fig. 3, looking in the direction of the arrows.

Fig. 5 is a fragmentary sectional view along the line 5—5 of Fig.’ 3.

Fig. 6 shows the application of gum to a cup sleeve, preparatory to the final positioning of a cup bottom.

Fig. 7 shows the cup bottom in register with the gum on a sleeve.

Fig. 8 illustrates spinning of the end of the ⁴⁰ cup sleeve, preparatory to engaging the cup bottom flange.

Figs. 9 and 10 illustrate the steps of interlocking and compressing the engaged flanges on the cup sleeve and bottom.

⁴⁵ Fig. 11 is a sectional view along the line 11—f I of Fig. 9.

Fig. 12 shows the appearance of a completed cup.

Fig. 13 is a fragmentary view, on an enlarged 50 scale, of a portion of the cup shown in Fig. 7.

Before proceeding with a detailed description of the various steps and related apparatus for carrying out the invention, a general description of the mode of operation involved will first be 55 outlined, with reference to the diagrammatic views of Figs. 1 and 2. As shown, a stack of blanks I is provided, the blanks I being of such form as to provide a hollow frusto-conical sleeve, when wrapped around a suitable cup form 2. In θθ its travel from the stack to the form 2, each blank (CI. 93—39.3)

I has a band of gum 3 applied to one straight edge thereof, and upon arrival at the form 2, the gummed blank is operated upon by suitable wrapping devices, indicated at 4. Operation of the device 4 serves to wrap the blank around the form ⁵2, with its straight edges in overlying relation, and with the gum 3 forming a seam extending longitudinally of the frusto-conical sleeve 5.

The particular mechanisms for wrapping each gummed blank around a cup form 2, are no part ¹⁰of the present invention, and are merely indicated as being of the type fully shown and described in Patent No. 1,876,931, issued September 13, 1932. Obviously, other types of mechanism may be employed for the purpose of providing a ¹⁵frusto-conical cup sleeve oh a form: 2, since the invention has wholly to do with the formation of bottom disks and their subsequent positioning in and cooperation with previously formed cup sleeves, for the purpose of providing water-tight ²⁰closures for the finished cups.

For purposes of illustration, the cup form 2 is shown as being mounted on a rotatable turret 6, in association with a plurality of similar cup forms, and the turret is given a step-by-step ro- 25 tative movement, so as to bring each form 2, with a cup sleeve 5 thereon, into register with various instrumentalities, at stations indicated A to ,F, inclusive. At these stations, previously formed bottom disks are inserted in the cup sleeves 5 30 and subsequently adhered thereto by a series of operations, hereinafter described. These bottom disks may be conveniently punched from a web • 7 that extends adjacent to the first station A, and as best shown in Fig. 2, each bottom disk 8, 35 punched from the web 7, is formed with an annular flange 9.

At station A, a bottom disk 8 is inserted, with its flange trailing in the smaller end of a cup sleeve 5 carried by a form 2, with the disk loosely 40 positioned in the sleeve 5 at an appreciable distance from the end thereof. At station B, an annular band of gum 10 is applied to the inside of the smaller end of the cup sleeve, after which, at station C, the bottom disk 8 is shifted 45 to bring its flange 9 in register with the gum 10. A. portion of the sleeve 5 then extends beyond the flange of the bottom disk, and this portion is next spun over at right angles to the axis of the sleeve, as indicated at station D. The spun-over lip at 50 the end of the cup is then turned inwardly into overlapping relation with the flange 9, as indicated at station E, after which 'the interlocked flanges are expanded radially outward to compress the same and cause close adhesion between 55 the gummed parts, as indicated at station F.

When a bottom disk 8 is shifted from its original position within a cup sleeve 5, its flange 9 engages the gum 10, and the present invention contemplates a procedure whereby the gum 10 60

2,216,331

Will Offit be appreciably disturbed by the advancing edge of the flange 9. In order to accomplish this result, each bottom disk 8 is formed so as to provide a series of crimps 1 i extending around 6 the periphery of the flange 9, and there will next be described suitable mechanism for cutting and crimping a bottom disk 8, as well as for inserting it in a cup sleeve, in advance of the gum applying operation.

Referring now to Figs. 3 and 4, the web 1 is fed across a die plate 12, providing openings 13 and 14 of different diameters. A punch sleeve 15 cooperating with opening 13 serves to sever a bottom disk blank 8α from the web 7, as indi¹⁵ cated in dotted lines, after which a second internal punch 16 is projected beyond the end of the punch sleeve 15 to thrust the blank through the smaller die opening 14, so as to form a flange 9. The flanged disk on the end of the punch 20 16 is then engaged with a rotatably driven tool 17, it being noted that the end portion of the punch 16 provides serrations 16α, and is free to turn. While the disk 8 is rotated by contact with the tool 17, the serrated surface of a crimp²® ing roll 18, mounted on a reciprocatory carriage 18α, is brought into engagement with the flange 9. A series of crimps 11 are thus formed around the periphery of the flange 9 by cooperation between the serrated surfaces of the roll 18 and ³® punch end, after which the punch 16 and the roll 18 are withdrawn; leaving the crimped bottom disk 8 held on the tool 17 by suitable suction means, as shown by pipe 17α.__

A reciprocatory slide 19, having an opening ³⁵ 19α in which the disk 8 is received during the crimping operation, then moves upwardly to carry the disk into register with a holder 20 that Is slightly tapered inwardly in the direction of an alined cup form 2 at station A of the turret 6. 40 A cup sleeve 5 is carried by the cup form 2, and a transfer plunger 21 then projects the bottom disk 8 through the holder 20 to insert the disk within the smaller end of the cup sleeve, after which the plunger 21 withdraws. The slight in45 ward taper of the holder 20* iends to somewhat contract the crimped flange 9, so that the disk enters readily within the small end of the cup sleeve. Obviously, a bottom disk 8 with crimps ί I formed in its flange 9, can be produced by 50 means other than· the particular mechanism of Figs. 3 and 4, which is shown for purposes of illustration.

After the insertion of a crimped bottom disk 8 at station A, the turret 6 is turned one step, 55 to move the cup sleeve and disk to the next station B. As best shown in Fig. 6, the bottom disk 8 with its crimped flange 9 facing towards the smaller end of the surrounding sleeve 5, then rests loosely within the sleeve, the disk 8 being 60 supported in a substantially vertical position by a head 22 mounted on a rod 22α movable within the cup form 2. While the cup sleeve remains at this station B, gum 10 is applied around the inside thereof substantially up to the crimped 05 flange of the disk 8.

The gum 10 is applied to the inside of the sleeve 5 by means of a gumming element 23 of less diameter than the open end of a sleeve, and movable with respect to the sleeve, by means of 70 a reciprocatory carrier 24. The gumming element 23 is mounted on a cylindrical holder 25 that is received within an opening 26 of the carrier, eccentric with respect to the central axis of the carrier 24, and the element is carried by 75 a spindle 23α eccentric within the holder 25.

When the gumming element 23 is inserted within the open end of the cup sleeve and the holder 25 is turned through a portion of a revolution, the combined eccentricities of the spindle, the carrier and the holder, cause the element 23 to 5 engage the wall of the sleeve 5. Rotation of the carrier 24 then applies the gum 10 in an annular band extending beyond the flange 9 . of the bottom disk substantially to the edge of the sleeve.

After application of the gum 10 within the 10 open end of the cup sleeve 5, the turret moves the gummed sleeve to station C, Fig. 7, where a tool 27 lightly engages the end of the cup sleeve 5, so as to prevent any movement thereof on the cup form 2. The rod 22α carrying the head 15 22 is then moved within the cup form to cause the head 22 to engage the bottom disk and shift it towards the gum 10. When the bottom disk 8 is so moved, the crimps 11 of the disk flange 9, engage the gum 10 only at spaced points around 20 the inner periphery of the sleeve. Therefore, as indicated in Fig. 13, the gum 10 is not wiped oft by the movement of the flange 9, bitt tends to be concentrated -in the spaces between the crimps ί I. Owing to the fact that the disk 8 25 is moved toward the smaller end of the sleeve, and is backed up by the head 22, the disk 8 remains in the position of Fig. 7, in register with the gum 10, during subsequent operations performed on the sleeve and the disk. 80

Referring now to Fig. 8, which shows the cup sleeve as having been moved to station D, a rotating spinning tool 28 is caused to engage the end of the sleeve 5 and spin over the gummed end portion of the sleeve, which extends beyond ³³the disk 8. The tool 28 is then withdrawn, and the turret turned again to bring the cup form with the spun-over sleeve to the next station E, as shown in Fig. 9. At this station, a cylindrical tool 29, having a diameter less than the in- 40 side of the bottom disk flange 9, is moved into the cup sleeve to engage the spun-over lip and convert it into an annular flange 30, loosely surrounded by the crimped flange 9. Since the act of spinning over the end of the cup sleeve 5 re- 45 suits in the formation of irregular crimps, due to the contraction of the material, the turnedin flange 30 will have a considerable irregularity of contour that causes it to interlock with the crimps 11, this relation between the flanges ³⁸9 and 30 hieing shown clearly in Fig. 11.

Upon withdrawal of the tool 29, the turret is turned through another step to bring the cup with the interlocked flanges 9 and 30 into posi- ’ tion at the final station F, as shown in Fig. 10. ⁶⁵At this station, an outside form 31 having an opening 31α with the same taper as the smaller end of the cup sleeve 5, is moved to engage the end of the cup sleeve. The form 31 is held by a casing 32 that is adapted for shifting movement with a carrier 33 which is also adapted to receive rotative movement. The carrier provides an opening 34 eccentric with respect to the carrier axis for receiving a holder 35 for an iron- _e5ing tool 36. The tool spindle 36α is eccentric with respect to the holder axis, and when the tool 36 is first inserted within the cup sleeve flanges and then turned through a portion of a revolution, the combined eccentricities of the 70 spindle, the holder and the carrier, cause the tool to closely engage the interlocked flanges 9 and 30, which are surrounded by the form 31. Rotation of the carrier 33 then causes close compression of the flanges 9 and 30 by the ironing 75

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2,216,331 tool 36, in cooperation with the form 31, which is held against rotation by its casing 32.

As a result of subjecting the interlocked flanges 9 and 30 to the action of the tool 36, the 5 crimping shown in Fig. 11 is entirely ironed out, and the gum between the crimps thoroughly distributed between the bottom disk flange 9 and the wall of the cup sleeve. The lower portion of a completed cup Is shown in section in Fig. 12, 10 from which it is evident that the flanges 9 and 30 are in very close engagement; with the upturned flange 30 presenting a smooth annular surface. In a completed cup, the bottom disk 8 is therefore very firmly adhered to the cup sleeve ¹⁵ 5, with the junction between the bottom disk flange 9 and the wall of the sleeve being entirely water-tight.