US3659507A

US3659507A - Machine for forming straws

Info

Publication number: US3659507A
Application number: US93082A
Authority: US
Inventors: Robert D Cushman
Original assignee: JENOS Inc
Current assignee: Pillsbury Co; JENOS Inc
Priority date: 1970-11-27
Filing date: 1970-11-27
Publication date: 1972-05-02
Anticipated expiration: 1989-05-02

Abstract

A machine for folding straws to temporarily alter a straw''s configuration, shorten it and form a liquid-tight seal in the straw. A rotating chuck folds the straw over anvil surfaces to form two crease lines in the straw. The chuck folds an upper straw section on these crease lines into perpendicular relationship with a lower straw section while forming a liquid tight seal at the folds.

Description

United States Patent 1151 3,659,507 Cushman 51 May 2, 1972 s41 MACHINE FOR FORMING STRAWS 3,242,828 3/1966 Larkin..... ....93/94 R 3,290,198 12/1966 Lux ....93/94 R [72] Inventor. Robert D. Cushman, Fort Lauderdale, Fla. 3,398,659 8/1968 Egleston "AB/84 Tw [73] Assignee: Jenos, Inc., Duluth, Minn. 3,452,516 7/1969 Smith ..93/84 TW 1 Fi1ed= 271 FOREIGN PATENTS 0R APPLICATIONS 1211 PP 931082 1,246,318 10/1960 1 France 229/7 5 717,909 11/1954 Great Britain ..93/84 TW 52 us. c1 ..93/84 Tw, 93/368, 93/94 R 8701551 6/1961 Great Britain -93/94 R [51] Int. Cl. ..B3ld 5/04,B3lc l1/02,B3lb45/00 [58] Field of Search ..99 171 B; 229/7 5; 93/36 M, Prmwry E-wmmerwayne Morse- 93/3 3 4 TW' 94 R Attorney-Hume, Clement, Hume & Lee

[56] References Cited ABSTRACT UNITED STATES PATENTS A machine for folding straws to temporarily alter a straws configuration, shorten It and form a lIquId-tight seal in the 2,054,024 9/1936 Pye ..93/84 TW t A rotating huck folds the straw over anvil surfaces to 1 1 4/1948 Bogoslowsky 93/36 8 form two crease lines in the straw. The chuck folds an upper 314601939 2/1 949 1 R straw section on these crease lines into perpendicular relation- 2-466183O 4/1949 Tofflemlre 93/84 Tw ship with a lower straw section while forming a liquid tight seal 2,800,265 7/1957 Pugh I ..229/7 S at the f ]d 2,901 ,357 8/1959 Epstein ..99/171 B 3,122,297 2/1964 Sachs ..229/7 8 13 Claims, 9 Drawing Figures Patented May 2, 1972 3,659,507

2 Sheets-Sheet l Patented May 2, 1972 3,659,507

2 Sheets-Sheet 2.

alm Z 10km MACHINE FOR FORMING STRAWS BACKGROUND OF THE INVENTION This invention relates in general to a machine for folding straws. It deals, more particularly, with a machine for folding straws to temporarily alter a straws configuration, shorten it and form a liquid-tight seal in the straw.

In the co-pending application of Justin M. Schmit, Ser. No. 32,933, filed Apr. 29, 1970, entitled STANDABLE FLEXI- BLE .CONTAINER WITH STRAW AND METHOD OF MANUFACTURING SAME, assigned to the same assignee as the present invention, the construction and use of a compartmented container having a straw extending between compartments is disclosed. One aspect of this invention is the arrangement and use of a fold complex in the straw which serves to shorten the straw and facilitate its proper positioning within one of the container compartments, as well as defining a seal against the passage of liquid through the straw, until the straw is unfolded. The present invention is specifically concerned with a machine for performing a fold sequence on a drinking straw to establish this fold complex.

SUMMARY OF THE INVENTION A primary object of the invention is to provide a simple machine for forming multiple folds in a conventional polyethylene plastic drinking straw to temporarily alter the straws configuration and shorten it while establishing a seal at the folds against the passage of liquids between container compartments. Another object is to provide a machine which performs a straw folding operation of the aforedescribed nature with a minimum of operations, in the simplest and most expeditious manner.

The foregoing and other objects are realized in accord with the present invention by providing a straw folding machine including a vertically disposed frame having a straw bending chuck mounted for rotation about a vertical axis. A straw bending anvil is also mounted on the frame in immediately adjacent relationship with the rotatable chuck. A retaining arm arrangement positions a straw in vertical relationship against the anvil, with the straw already positioned in the plastic container as illustrated in the aforementioned co-pending application entitled STANDABLE FLEXIBLE CONTAINER WITH STRAW AND METHOD OF MANUFACTURING SAME. The liquid receiving compartment of the container may be empty or it may have been previously filled.

The anvil includes a first linear anvil surface which extends transversely of the axis of the upright straw and is inclined at an angle of approximately 45 to the axis. Initial rotation of the chuck bends the straw over this anvil surface, whereby the straw is creased along an inclined crease line L and folded on this crease L until the upper section of the straw has been folded into a position perpendicular to the upright lower section of the straw. At this point, the chuck has made one rotation through 360.

The anvil includes a second linear anvil surface which extends parallel to the axis of the upright lower straw section and immediately adjacent to one of its edges. Continued rotation of the chuck folds the straw about this second anvil surface and a second crease line L corresponding to the aforementioned vertical edge of the lower straw section. Folding of the top section of the straw about the second crease continues under the influence of the rotating chuck until the straw segment has been folded through an additional 180 (the chuck has rotated through 540), thus completing a 360 folding of the straw top section about its own axis through two folds at the first crease L, and the second crease L A cam arrangement on the chuck is effective, after this 540 of rotation of the chuck to actuate an anvil release mechanism, causing the anvil to be pivoted downwardly and out of engagement with the folded straw. The folded straw, with its container into which the lower straw section extends, is then moved to the next station where container flap guides pick up side flaps of the partially completed container about the folded straw and position them for ultimate sealing into a straw container compartment. The chuck rotates through an additional to complete 720 of rotation and one full cycle of operation of the machine.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a front elevational view of a straw folding machine embodying features of the invention, with a straw in its container positioned for folding;

FIG. 2 is a view similar to FIG. 1, with parts removed, showing the machine with its straw folding chuck rotated through 180 of a 720 folding cycle;

FIG. 3 is an enlarged end view of a cam operator and its relation to a straw anvil release mechanism with the chuck positioned as illustrated in FIG. 2;

FIG. 4 is an enlarged view of a portion of the cam operator construction;

FIG. 5 is an enlarged view of another portion of the cam operator construction;

FIG. 6 is a view similar to FIG. 2 showing the straw folding chuck after 360 of rotation in the 720 folding cycle;

FIG. 7 is an enlarged view of the cam operator as positioned when the rotating chuck approaches (from the position shown in FIG. 6) its 540 position in the 720 folding cycle;

FIG. 8 is a view similar to FIG. 6 showing the straw folding chuck in its 540 position of the 720 folding cycle; and

FIG. 9 is a view of the cam operator taken along line 9-9 of FIG. 8.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the drawings, and particularly to FIG. I, a straw folding machine embodying features of the present invention is illustrated generally at 10. The machine 10'includes a vertically disposed frame 11 which includes a base member 12, a vertical post 13 extending upwardly from the base member, and a mounting bracket 14 secured to the upper end of the post 13.

The bracket 14 includes a cantilevered arm 20 extending outwardly from the post 13 and a body counterweight 21. The body 21 is clamped to the vertical post 13 with an adjusting screw 22, facilitating vertical adjustment of the bracket 14 on the post 13, for reasons hereinafter discussed in detail.

Having described the machine 10 to this extent, it is necessary before continuing a description of the construction and operation to describe the positioning of the container C and the straw S. The construction of the container C and the arrangement of the straw S in the container is described in detail in the aforementioned co-pending application entitled STANDABLE FLEXIBLE CONTAINER WITH STRAW AND METHOD OF MANUFACTURING SAME.

The container C, with its lower compartment filled with liquid (in the illustrated example) and the straw S extending vertically therefrom, is seated on the base 12 by suitable mechanical means. In this position, the straw protrudes from the lower compartment of the container C and extends into immediately adjacent relationship with a chuck assembly 30 mounted on a vertical pin 31 affixed to the outer end of the arm 20 for rotation about the axis of the pin. In the illustration of FIG. 1, it will be seen that the straw extends upwardly in front of the chuck assembly in normal, unactuated relationship of the machine 10.

In this relationship, the straw S is positioned against the anvil arm 35 which is pivotally mounted for vertical movement on a pin 36 on the frame post 13. In a manner hereinafter described, the chuck assembly 30 is effective to fold the straw S on the anvil 35 to form a fold complex which shortens the straw and defines a liquid tight seal in the straw, preventing the efflux of liquid from the lower compartment of the container C as long as the straw is folded.

The anvil arm 35 is formed of metal strip and includes an anvil section 37 formed at its outermost end. It is the anvil section 37 against which the straw S is placed. The anvil section 37 includes a first linear anvil surface 40 which extends transversely of the axis of the upright straw and is inclined at an angle of approximately 45 to the axis. The anvil section 37 includes a second linear anvil surface 41 which extends parallel to the axis of the upright straw S and immediately adjacent to one edge of this straw, as viewed in front elevation in FIG. 1.

The anvil arm 35 is normally biased into horizontal relationship wherein the anvil surfaces 40 and 41 are arranged in the manner hereinbefore described, by an anvil arm coil spring 45 disposed between an extension 46 of the anvil arm 35 and a mounting bracket 47 adjacent the base 12 on the frame 11 The anvil arm 35 is stopped in this horizontal position against further movement under the influence of the spring 45 by a stop screw 49 which is adapted to engage the upright post 13 with the anvil arm in this position.

The chuck assembly 30 includes a mounting block 55 from which a straw bending head 56 depends. The straw S is, before actuation of the machine in a folding cycle, disposed immediately adjacent the front face 60 of the head 56. The upper end of the straw is actually positioned in front and slightly to one side of a generally conical groove 61 formed in the face 60 of the head 56 and converging upwardly from a widened area at the base 62 of the head 56 to a narrower area at the top 63 of the head 56. At the base 62 of the head 56, the groove 61 is sufficiently deep to extend into the back face 66 of the head 56, thus creating a generally elliptical cut-out 67 in the back face 66, extending upwardly from the base 62 of the head.

The groove 61, adjacent which the upper end of the straw S is disposed prior to beginning of the straw folding operation by the machine 10, is offset slightly in the direction of its axis pin 31 from the axis of the straw in this relationship. At the same time, the axis of the straw S and the groove 61 are offset from the axis of rotation of the chuck assembly 30 in the direction of the post 13. The significance of this offset relationship will be explained in the description of the operation of the machine 10. i

It is the rotation of the straw bending head 56 about the axis of its mounting pin 31 which is effective to fold the straw S about the anvil surfaces 40 and 41 hereinbefore described. One folding cycle of the machine is effected by rotation of the chuck assembly 30 through 720, or two complete 360 halfcycles, returning to its normal or starting position, as illustrated in FIG. 1.

During the first 360 half-cycle of the folding operation performed by the rotating chuck head 56, after approximately 180 of rotation, as seen in Fig. 2, the upper end of the straw S has just been engaged by the head 56 at the outermost extremity 70 of one side of the groove 61. Continued rotation of the head 56 bends the straw S over the anvil surface 40, creasing it along an inclined crease line L and folding the upper section of the straw on this line L until the head has rotated through one full half-cycle or 360, as seen in FIG. 6. At this point, the upper section of the straw, above the crease line L,, has been folded into a position perpendicular to the upright lower section of the straw below the crease line L In effecting this folding of the upper section of the straw S about the crease line L,, from initial contact of the groove area 70 with the straw through 360 of rotation of the head 56, the upper section of the straw S rides in the groove 61 and is guided into the aforedescribed relationship perpendicular to the lower straw section.

As the straw S approaches this perpendicular (horizontal) relationship, wherein it extends generally parallel to the anvil arm 35, it moves downwardly out of the groove 61 until it actually slips underneath the base 62 of the head 56, as seen in FIG. 6. At this point, the upper section of the straw S comes into engagement with the straw bending guide pin 75 which depends from the base 62 of the head 56 opposite the axis of rotation of the chuck assembly from the groove 61. An enlarged head 76 is formed on the lower end of the pin 75 to prevent the straw from slipping off.

With the initially folded upper section of the straw S biased by its own resiliency against the guide pin 75, continued rotasum tion of the chuck assembly 30 folds the upper section of the straw about the second anvil surface 41, forming a vertical crease line L until the straw section has been folded through an additional 180 (the chuck assembly 30 has rotated through 540), as seen in FIG. 8, thus completing a 360 folding of the straw top section about its own axis through two folds at the first crease L and the second crease L When the chuck assembly has rotated through 540 of the 720 straw folding cycle, a cam unit 80 on the chuck assembly 30 is effective to engage and depress a straw release arm 81 mounted for pivotal movement at 82 on the vertical post 13 of the machine frame 1 1. The cam unit 80 engages the inner end 85 of the release arm 81, forcing it downwardly and, accordingly, forcing the outer end 86 of the cam arm upwardly. The outer end 86 of the cam arm 81 is connected, by suitable linkage 87, to the extension 46 of the anvil arm 35. Accordingly, it pivots the anvil arm 35 on its mounting pin 36, against the bias of the spring 45, forcing the anvil section 37 of the anvil arm downwardly and out of engagement with the straw fold complex formed at thecrease lines L and L The construction and operation of the cam unit 80 in its engagement with and depression of the release arm 81 is best understood by reference to FIGS. 3-9. The cam unit 80 includes an elongated cam 90 rotatably mounted on a pin 91 extending perpendicular to the axis of rotation of the chuck assembly 30 of the chuck head 56. Secured to the end of the pin 91 on a mounting disc 92 is a conventional split lock washer 93. Secured to the inner surface of the cam arm 90 is a cooperating bearing disc 94. Dimples are formed at 90 intervals around the disc 94 so that in rotation of the arm 90 on the shaft 91 they seat in the washer gap 93a, engage the partially outwardly sprung end of the washer, and act as a stop in positioning the cam arm 90 and preventing its otherwise free rotation on the shaft 91.

The cam arm 90 is preset in the position illustrated in FIG. 4 at the outset of an operational folding cycle of the machine 10. In this position, it will be noted that the arm 90 is horizontally disposed. A dimple on the disc 94 in the lock washer gap 930 lightly holds the cam arm 90 in this position.

When the chuck assembly 30 has rotated through the first of its rotational folding cycle, as it begins to fold the straw about the crease line L a depending inclined cam face 97 on the cam arm 90 engages the inner end 85 of the release arm 81. Since the cam arm 90 is only lightly held in its horizontal relationship by the seating of the dimple 95 in the lock washer slot 93a, this engagement causes the cam arm 90 to rotate approximately 30 about the axis of its mounting pin 91, as illustrated in FIG. 3. The cam arm 90 is retained in this position by the friction between the dimples 95 on the disc 94 and the lock washer 93 until the chuck assembly has rotated through an additional 360 bringing the straw to its fully folded relationship and the cam assembly 80 back into engagement with the release arm 81.

At this point, as best seen in FIG. 7, the arcuate cam surface 98 engages the release arm free end 85. Further rotation of the chuck assembly 30 effects a depression of the release arm 81 and a continued rotation of the cam arm 90 into the relationship illustrated in FIG. 9. At this point, the release arm 81 has pivoted the anvil arm 35 downwardly to withdraw the anvil section 37 from engagement with the folded straw S.

The straw S is now completely folded according to the invention. At this point, the container C is withdrawn horizontally from the machine 10, between arcuate container flap guides 99, extending onto opposite sides of the container immediately below the straw fold, from the cantilevered arm 20. By drawing the container C outwardly between these arms 99, flaps of the container lying down over the guides during the folding operation are forced upwardly alongside the folded upper section of the straw S into position for scaling to form an upper container compartment which encloses the folded straw.

Continued rotation of the chuck assembly 30 through its final 180 of the 720 folding cycle further rotates the cam arm about its mounting pin axis 91 until it finally disengages with the release arm surface 85. Although the cam arm may not return to a precisely horizontal relationship at this point, it is unnecessary that it do so, since in the next cycle of operation its initial engagement of the cam face 97 with the release arm free end 85 will still serve to position the arm 90 as illustrated in FIG. 3.

Rotation of the chuck assembly 30 is effected by a conventional electric motor 100 and belt 101 to a pulley 102 on the shaft 31. Suitable timing devices and circuitry sequence the rotation in the aforedescribed manner.

The head 14 is vertically adjustable, as hereinbefore pointed out. Variations in straw length can thus be accommodated easily.

While the embodiment described herein is at present considered to be preferred, it is understood that various modifications and improvements may be made therein.

What is desired to be claimed and secured by Letters Patent of the United states is:

l. A machine for folding a straw to temporarily change the configuration and dimensions of the straw and form a liquidtight seal in the straw, comprising:

a. anvil means b. means for holding an unfolded straw with its cylindrical side wall disposed immediately adjacent said anvil means,

. chuck means rotatable on an axis parallel to the axis of the unfolded straw,

. straw directing means on said chuck means,

. rotation of said chuck means causing said straw directing means to fold an upper section of said straw on said anvil means into perpendicular relationship with a lower section of the straw and establish a liquid tight seal between said upper and lower straw sections.

2. The straw folding machine of claim 1 further characterized in that:

a. a first linear anvil surface formed on said anvil means and extending transversely to the axis of the unfolded straw and at an oblique angle thereto,

b. a second linear anvil surface on said anvil means and extending substantially parallel to the axis of the unfolded straw,

. rotation of said chuck means causing said upper section of said straw to fold on a first crease line over said first anvil surface and on a second crease line over said second anvil surface.

3. The straw folding machine of claim 2 further characterized in that:

a. said chuck means rotates from a starting position through a 720 cycle of rotation to a finish position in folding the upper section of the straw about said first linear anvil surface and said second linear anvil surface into perpendicular relationship with the lower section of the straw.

4. The straw folding machine of claim 3 further characterized in that:

a. rotation of said chuck means from its starting position through 360 of its 720 cycle being effective to fold the straw over said first linear anvil surface on said first crease line into perpendicular relationship with the lower straw section,

b. rotation of said chuck means from the 360 position in its folding cycle to its 540 position in its folding cycle being effective to fold the upper straw section over said second linear anvil surface on said second crease line to complete the folding of the straw and establishment of said liquidtight seal while maintaining a perpendicular relationship between the upper straw section and the lower straw section.

5. The straw folding machine of claim 4 further characterized in that:

a. said chuck means includes a chuck head,

b. said straw directing means including a groove formed in one face of said chuck head in generally parallel relationship with the axis of rotation of said chuck means and the axis of the unfolded straw,

c. said groove being effective to engage the straw as the chuck head rotates through the first 360 of the 720 straw bending cycle of the anvil means to fold the upper straw section over said first linear anvil surface into perpendicular relationship with the lower straw section.

6. The straw folding machine of claim 5 further characterized in that:

a. said straw directing means further includes a straw directing pin means extending from the base of said chuck head in generally parallel relationship with the axis of rotation of the anvil means and the axis of the unfolded straw,

b. said pin means engaging the upper section of the straw after approximately said initial 360 rotation of the chuck means and directing said straw to fold around said second linear anvil surface on said second crease line as said chuck head rotates through said 360 to 540 portion of its straw folding cycle.

7. The straw folding machine of claim 6 further characterized in that:

a. said anvil means is movable from an operative position for engagement by the straw and folding of the upper straw section over said first and second linear anvil surfaces, and an inoperative position,

b. actuator means on said chuck means for causing said anvil means to move from its operative position to its inoperative position when the chuck means has rotated through 540 of its 720 straw folding cycle and the upper straw section has been folded on said first and second crease lines into perpendicular relationship with the lower section of the straw.

8. The straw folding machine of claim 7 further characterized in that:

a. said actuator means comprises a cam mounted on said chuck means,

b. an anvil arm connected to said anvil,

c. said cam adapted to engage said anvil arm and cause it to move said anvil from its operative position to its inoperative position as the rotating chuck means passes the 540 position in its 720 cycle of rotation.

9. The straw folding machine of claim 8 further characterized by and including:

a. resilient means normally urging said anvil means from its inoperative position to its operative position.

10. The straw folding machine of claim 9 further characterized in that:

a. said cam is rotatable on said chuck means about an axis extending generally perpendicular to the axis of rotation of the chuck means,

b. a first cam surface on said cam for engaging said arm and cocking said cam as it passes through its 360 position in the 720 cycle of rotation of the chuck means,

0. a second cam surface on said cam for engaging said actuator arm only with the cam in its cocked position as the rotating chuck passes through its 540 position in its 720 cycle of rotation.

11. A machine for folding a straw to temporarily change the configuration and dimensions of the straw and form a liquidtight seal in the straw, comprising:

a. means for supporting a straw,

b. means for folding an upper section of said straw in a predetermined direction about a first crease line in said straw to bring said upper section into a first position generally perpendicular to the lower section of said straw, and

c. means for further folding said upper section of said straw in substantially the same direction about a second crease line in said straw adjacent said first crease line into a position extending in substantially the opposite direction from the first position of said upper straw section.

12. The straw folding machine of claim 11 further characterized by and including:

a. means for forming said first crease line in said straw at an oblique angle to the axis of the unfolded straw.

13. A method of folding a straw to temporarily change the said first crease line and extending generally parallel to configuration and dimensions of the straw and form a liquid the axis of the other straw section, and tight seal in the straw, comprising the steps of: d. folding the upper section of said straw about said second a. creasing the straw intermediate its ends along a fir t crease line until said upper section extends in a direction crease line extending diagonal to the axis of the straw, Substantially pp that in which it resides being initially folded about said first crease line into a position generally perpendicular to the other end section of said straw.

b. folding one end section of the straw on said first crease line into generally perpendicular relationship to the other end section of the straw,

c. creasing the straw along a second crease line adjacent

Claims

1. A machine for folding a straw to temporarily change the configuration and dimensions of the straw and form a liquid-tight seal in the straw, comprising: a. anvil means b. means for holding an unfolded straw with its cylindrical side wall disposed immediately adjacent said anvil means, c. chuck means rotatable on an axis parallel to the axis of the unfolded straw, d. straw directing means on said chuck means, e. rotation of said chuck means causing said straw directing means to fold an upper section of said straw on said anvil means into perpendicular relationship with a lower section of thE straw and establish a liquid tight seal between said upper and lower straw sections.

2. The straw folding machine of claim 1 further characterized in that: a. a first linear anvil surface formed on said anvil means and extending transversely to the axis of the unfolded straw and at an oblique angle thereto, b. a second linear anvil surface on said anvil means and extending substantially parallel to the axis of the unfolded straw, c. rotation of said chuck means causing said upper section of said straw to fold on a first crease line over said first anvil surface and on a second crease line over said second anvil surface.

3. The straw folding machine of claim 2 further characterized in that: a. said chuck means rotates from a starting position through a 720* cycle of rotation to a finish position in folding the upper section of the straw about said first linear anvil surface and said second linear anvil surface into perpendicular relationship with the lower section of the straw.

4. The straw folding machine of claim 3 further characterized in that: a. rotation of said chuck means from its starting position through 360* of its 720* cycle being effective to fold the straw over said first linear anvil surface on said first crease line into perpendicular relationship with the lower straw section, b. rotation of said chuck means from the 360* position in its folding cycle to its 540* position in its folding cycle being effective to fold the upper straw section over said second linear anvil surface on said second crease line to complete the folding of the straw and establishment of said liquid-tight seal while maintaining a perpendicular relationship between the upper straw section and the lower straw section.

5. The straw folding machine of claim 4 further characterized in that: a. said chuck means includes a chuck head, b. said straw directing means including a groove formed in one face of said chuck head in generally parallel relationship with the axis of rotation of said chuck means and the axis of the unfolded straw, c. said groove being effective to engage the straw as the chuck head rotates through the first 360* of the 720* straw bending cycle of the anvil means to fold the upper straw section over said first linear anvil surface into perpendicular relationship with the lower straw section.

6. The straw folding machine of claim 5 further characterized in that: a. said straw directing means further includes a straw directing pin means extending from the base of said chuck head in generally parallel relationship with the axis of rotation of the anvil means and the axis of the unfolded straw, b. said pin means engaging the upper section of the straw after approximately said initial 360* rotation of the chuck means and directing said straw to fold around said second linear anvil surface on said second crease line as said chuck head rotates through said 360* to 540* portion of its straw folding cycle.

7. The straw folding machine of claim 6 further characterized in that: a. said anvil means is movable from an operative position for engagement by the straw and folding of the upper straw section over said first and second linear anvil surfaces, and an inoperative position, b. actuator means on said chuck means for causing said anvil means to move from its operative position to its inoperative position when the chuck means has rotated through 540* of its 720* straw folding cycle and the upper straw section has been folded on said first and second crease lines into perpendicular relationship with the lower section of the straw.

8. The straw folding machine of claim 7 further characterized in that: a. said actuator means comprises a cam mounted on said chuck means, b. an anvil arm connected to said anvil, c. said cam adapted to engage said Anvil arm and cause it to move said anvil from its operative position to its inoperative position as the rotating chuck means passes the 540* position in its 720* cycle of rotation.

9. The straw folding machine of claim 8 further characterized by and including: a. resilient means normally urging said anvil means from its inoperative position to its operative position.

10. The straw folding machine of claim 9 further characterized in that: a. said cam is rotatable on said chuck means about an axis extending generally perpendicular to the axis of rotation of the chuck means, b. a first cam surface on said cam for engaging said arm and cocking said cam as it passes through its 360* position in the 720* cycle of rotation of the chuck means, c. a second cam surface on said cam for engaging said actuator arm only with the cam in its cocked position as the rotating chuck passes through its 540* position in its 720* cycle of rotation.

11. A machine for folding a straw to temporarily change the configuration and dimensions of the straw and form a liquid-tight seal in the straw, comprising: a. means for supporting a straw, b. means for folding an upper section of said straw in a predetermined direction about a first crease line in said straw to bring said upper section into a first position generally perpendicular to the lower section of said straw, and c. means for further folding said upper section of said straw in substantially the same direction about a second crease line in said straw adjacent said first crease line into a position extending in substantially the opposite direction from the first position of said upper straw section.

12. The straw folding machine of claim 11 further characterized by and including: a. means for forming said first crease line in said straw at an oblique angle to the axis of the unfolded straw.

13. A method of folding a straw to temporarily change the configuration and dimensions of the straw and form a liquid tight seal in the straw, comprising the steps of: a. creasing the straw intermediate its ends along a first crease line extending diagonal to the axis of the straw, b. folding one end section of the straw on said first crease line into generally perpendicular relationship to the other end section of the straw, c. creasing the straw along a second crease line adjacent said first crease line and extending generally parallel to the axis of the other straw section, and d. folding the upper section of said straw about said second crease line until said upper section extends in a direction substantially opposite that in which it resides after being initially folded about said first crease line into a position generally perpendicular to the other end section of said straw.