US 2363957 A
Description (OCR text may contain errors)
NOV. 28, 1944. Q 2,363,957
ENVELOPE OR CONTAINER Filed Dec. 2, 1942 INVENTOR: CE 50511: GOFF;
Patented Nov. 28, 1944 ENVELOPE OR CONTAINER George H. Goff. Fltchbllrg, Mesa, asslgnor to The Brown'Bag Filling Machine C R poration of Massachusetts Application December 2, 1942, Serial No. 467,636
The invention relates to envelope or bags suitable for use in automatic measure and filling machines for the packaging of pulverulent and similar materials.
Containers of this type have become of considerable importance within recent years, because of the greatly increased use of packages of goods of various kinds put up in small quantities, and especially those adapted to be packaged by automatic packaging machinery. The general trend has been toward the development of fiat bags or envelopes, and notwithstanding that numerous improvements have been made in such containers there is still not complete satisfaction with those'heretofore available, either because of excessive costs, or excessive bulkiness of the container, faultiness of functioning of the package for the size of the contents, or otherwise, sanitary considerations, and esthetic considerations, with possibly other effects not at this time enumerated.
It is therefore an aim of the present invention to effect a further step of improvement toward meeting the objections noted as well as attaining advantages in other respects. On account of the fact that gums used in securing the closures of such packets being either capable of affording a media for bacterial development or/and fungus propagation such as mold, as well as the antipathy of the public to having food come in contact with such adhesives, whether this antipathy is justified or not, it is an important aim of the present invention to embody a quick opening envelope suitable for use as a food container, and especially of pulverulent foods such as flour samples, individual cocoa servings, andother materials, in which the contents will be protected from contact with adhesive materials, not only whilethe package is sealed, but as it is opened and as the contents are discharged therefrom.
In prior envelopes it has been a serious objection that where the opening means consists of a bottom flap including both walls of a fiat envelope folded on a crease entirely across the envelope and the flap thus formed detachably secured to the back of the envelope, when such envelope is opened by the pulling loose of the flap the creases in the paper and the inherent tendency of the paper to retain its creased or folded form cause the two walls of the envelope to tend to remain pressed together, interfering with the proper discharge of the contents and requiring the user to insert the fingers into the end of the envelope to press the walls apart, or to otherwise expend time and effort in attaining this end, with poor success in many instances. It is therefore an aim of the present invention to overcome this objection, while retaining the advantages of the bottom flap of the general kind in dicated. One of the principal reasons for the tendency of such pull-down bottom flaps to remain closed is the attachment or continuity of both walls of the envelope in the flap portions at the side fold of the envelope, and it is an aim of the present invention toenable the complete disconnection of the extension of the front wall of the envelope from the extension of the back wall in the bottom flap of the envelope in an opening means of this general character. In detachable bottom flaps of this general type last mentioned. where the flap is secured to the back wall of the envelope by a weak adhesive, in such manner that the upturned flap may be pulled away from the back wall of the envelope and so detached therefrom, the attachment of the bottom flap to the back wall of the envelope has been lacking in security, and has involved the liability of accidental opening of the passage, and it is an aim of the present invention to increase the security of the closure while retaining all the advantage of great ease of opening and possibility of rapid manipulation for that purpose.
In such envelopes means has not heretofore been devised to enable the use of weakened lines in the paper stock to enable ready severance of the paper of the envelope along such lines: as will result in a satisfactory opening of the envelope. Recent developments of methods of forming weakened lines in paper stock have made this a very certain and effective means for effecting severance of paper along arbitrary lines, with possibility of great range of direction and form in the severed parts, and it is therefore an aim of the present invention to enable the utilization of such weakened lines, especially those known as "perforations while retaining all of the advantages of a safe sealingof the package against escape of pulverulent materials through such perforations, corresponding to the result of a glued seam across the envelope.
It is also an aim of the invention to provide such an envelope which may be opened by the simple expedient of pulling a simple tab toward the end of the envelope while the opposite end of the envelope is held, and resulting in the opening of the envelope with full clearance of the con tents for discharge, without delay or further manipulation to induce the separation of the wall portions of the envelope at its opened end.
In the production of packages embodying this general style of opening means and in which a tubular container on a transverse line so that parts of both the front and back walls are included in the fiap outwardly of the line of fold and then securing this flap to the back of the package, dii'ficulty has been experienced where thin paper is employed in the container. Very fine pulverulent material so packaged is found to sift out by escaping between the two walls at the transverse crease or fold in the central part. Where the double wall fold is not employed and a bottom flap on one wall is turned in around the bottom edge of the other wall of a continuous gum seal used so as to prevent escape of fins material at the central part of the bottom, it is found that the content still escapes at each side of the bottom of the package in the crease of the bottom flap. It is therefore an object of this invention to enable the use of my improved opening means in the last named type of fold as well as a simple fiat bag closure where a bottom tongue on one wall is folded at and around the bottom edge of the other wall.
Additional objects, advantages and features of invention may be understood from the following detailed description thereof, and the accompanying drawing presenting the invention in its best known embodiment. In the drawing,
Figure l is a plan of the paper blank for forming a fiat bag or envelope embodying my invention.
Figure 2 is a back view of the bag partly completed, showing it in its tubular form Figure 3 is a back view of the lower end of the bag completed, and initial manipulation for its opening being indicated in dotted lines.
Figure 3-a is an edge view of the bag showing a further stage in one method of manipulation for opening.
Figure 4 is a back view of the container opened.
Figure 5 is a fragmentary end view of the bag opened.
Figure 6 is a longitudinal sectional view of the lower end of a package embodying my invention, and showing the initial manipulation for opening the same.
Figure 7 is a longitudinal sectional view of the bag showing one manner of final manipulation in emptying the package.
There is illustrated an envelope formed from a blank as shown in Figure l, which includes a body portion or front wall portion 2|, on which side flaps 22 and 23 are formed, adapted to be folded inward on the crease lines 24, so as to overlap and form a back wall 25 of the container, as in Figure 2. At this stage the article may be termed a flattened tube. The side fiap 22 in this form of the invention is narrower than the other and is provided with a gummed zone 23 parallel to the vertical or longitudinal edge of the flap, so that when this flap is folded over the other on the line 24 the two are secured together, so that the lapped portions of the back wall are paced from the medial longitudinal line of the envelope. From the top edge of the front wall portion 2i there is projected a longitudinal closure tongue 21, conforming to usual practices in such envelopes, and in the manufacture of this envelope this closure tongue is uncoated with gum, so as to facilitate the use of the envelope in thebag filling machine, wherein gum. is usually applied to this tongue incident to the sealing of the envelope by the machine. The side crease lines of the flaps 22 and 23 indicated at 24 by dotted lines are parallel to each other, and
seal is attempted by folding the end of a flattened the upper and lower boundaries or the finished face of the front wall 2i are indicated by additional dotted lines 23 and 23, respectively, defining a rectangularboundary for the front wall 2|. The side flaps, and in consequence, the back wall '2', extend upwardly beyond the defined face portion of the wall 2i, as indicated by the line 23, but in Figures 1 to 7, stop at the level of the line 23 defining the lower ends of the walls. From the lower edge of the blank there is extended a closure tongue or bottom fiap 33, coextensive with the full width of the face portion 2i of the envelope. This flap encloses a substantially triangular opener tongue area 3i, and in addition, integral side portions 32 shaped as lobes having arcuate bounding edges, which, as viewed in Figure 1, are inclined downwardly and curved inwardly from near the base of the flap toward the longitudinal medial line of the front wall 2i 9, distance, and are then recurved inwardly and upwardly as at 33, to points spaced apart transversely of the container and located at the sides of a wide tab element 34, usually formed with a width at its base' of an inch or more, Figures 3 and 4 being full size of an article as produced and used. The tab has a length longitudinally of the blank from the points 33 appropriate to the use: hereinafter described, and ordinarily less than one-half inch, the example shown being about one-quarter inch in depth. The base of the tab 34 preferably is inwardly of the curved boundaries of the lobes 32, and spaced from the bottom line 29 of the front wall a substantial distance, and while this is not arbitrary, it has been 35 found in practice satisfactory to space the base of the tab about-an inch from the line 23 On a container 3% inches wide. The curves defining the outer edges of the lobes are, in the present instance, substantially parabolic, with the axis of 49 the parabola nearer the tab than to the side tion of the flap includes fillets 38, which are small triangular areas of the blank integral with the base body of the flap and with the flaps 22 and 23 respectively, at and. outwardly of the line 23, and outwardly of the lines 24, so that in the folding of the side flaps on the lines 24 each crease formed extends across the junction of the fillet and the flap 30 and the fillet is turned. inward over the adjacent .portion of the base of the flap 30, as seen in Figure 2. Then, when the flap 30 is .folded on the line 23 upwardly and inwardly onto the back wall 25, as shown in Figures 3 and 6, the fillet is included within and under the folded fiap at each corner of the container, forming a complete closure and seal of the crease. at each end and for a distance inwardly, and in addition, providing a terminal dam between the back wall 25 and flap 30 at each end of the zone or area of abutment of the flap 30 and back wall 25. The intervening lower edge of the back wall 2! lies snugly in the crease at 20.
The lobes 32 have adhesive 33 applied thereto in zones spaced close to the opener tongue area 3| and extending from immediately adjacent or including the fillets to the sides of the tab 34, or close to the latter. i
There is also applied to the container either on the external face of the back wall "or the inner tearing of either the flap '30: srws r l* -The stripof special adhesive material stops at the diagonal edges of the' fillets, when the bottom flap is folded upwardand secured, and lies with its ends within the defined area of the opening tongue 3| in the present instance, and is of a thickness approximately that of the paper of which the container is formed. Although this thickness has certain novel advantages, as will be explained, it is not essential. The gum 36 and adhering material 31 are applied by the envelope-making machine incident to the formation of the container, and the bottom flap immediately folded upward against the wall 25, by the machine, so that the flap is secured fiat against the back wall. The material 31, extends between or on to the fillets 35 in the completed container, so that the partial dam formed by the fillets is completed by the material 31. In addition, the thickness of the material 31 presses the lower edge of the back wall snugly against the front wall so that sifting of fine material from within a package around the bottom edge of the back wall is prevented. In addition, the material 31 forms a continuous attachment of the back wall edge and bottom flap so that possibility of separation of the front and back wall parts on the crease of the latter due to distortion of the package form is opposed. Such separations might otherwise occur without the closely located continuous rectilinear attachment at 31, when the lower edge of a package is bent out of good rectilinear form, or under various strains to which a package of thin paper is readily subject, including, for instance, relative longitudinal movements of the front and back walls, unequal pressures in transversely spaced areas of the package, and otherwise. In this way, also,
likelihood of contents coming in contact with the.
material 31 is minimized so ,that some suitable simple adhesive may be employed in the entire body of material 31, without requiring it to be of special quality, as to sterility, odor, or flavor. The momentary contact involved when the package is emptied, as will be described, will be of no material efiect.
Within the flap 30, the opener tongue 3| is defined by two lines or series 38 of slits 39 formed through the paper of the blank at each side of the area 3|, the series of slits being substantially rectilinear at each side, and the series extending from adjacent the respective points 33 to points close to the intersection of the side boundaries 24 of the front wall 2| and the bottom line 29 defining the lower edge of the wall 2|. These slits 29 are each formed in such manner that thereof.
though the paper is severed at the slit, the mate-- of objects striking the paper becoming engaged in any of the slits so as to tend to tear the paper The slits in the present instance are so arranged that but few are required and are approximately spaced apart from each other oneeighth inch in the package of Figures 3-4, although this may be varied, or the ends stop short of lapping, in some instances.
The slits 39 are inclined generally in a direction from'the lower corner or base of the bottom flap inwardly and upwardly toward the central r0r i Qn',Q ;the. ab;3 In the $l in t they areall locatedon lines arrangedat an angle to the base line 29 closely approximating 30 degrees, although this angle may be somewhat varied without materially changing the function of the article. The downward inclination has a material effect in improving the opening function to be described.
In the present instance, there are but three slits in each series 38, but if shorter slits are employed more will be required. The parallel lines on which the slits are located in each series as shown are spaced approximately one-sixteenth of an inch apart, which affords good strength in resisting accidental disruption of the connection between the opening tongue 3| and the holding lobes, while disposing the short connecting ribbon 4| between the lapped ends of the slits39 at such angle to the direction of shearing stress in the opening operation that a maximum of ease in opening and a maximum definiteness of directionof severance and separation of the tongue 3| and attaching parts is assured.
It should be noted that the tab 34 is formed with rounded outer corners at its ends, its transverse edge being rectilinear, and its sides being slightly divergent at its terminations and extending below the junction points 33 of the curved edges of the lobes therewith. Thus, the base of the tab is defined at each side by short slits 49 extending into the fabric sheet a distance. This, in addition to the angle formed by the junction of the lobe edge and tab edge, has an important function in definitely determining the point of beginning of tear and also facilitating the tear, when the package is to be opened, as will be described. At the same time the tab is held close against the back wall by the secured lobes 32 until opening of the article is deliberately prac ticed.
In the operation of opening the package, the package is held approximately erect in one hand, and the first and second digits of the other hand are presented with the finger nails next to the back wall 25 and longitudinally inward of the transverse end edges of the tab, and the nails engaged against this edge so as to separate it from the back wall and the same fingers pressed against its under side. The raised tab is then grasped between the same two fingers and the thumb and pulled outward from the medial plane of the container and also longitudinally outward and downward toward the bottom edge of the package where the crease line 29 is located. This causes the fabric to be torn beginning at the bottoms of the slits 40, and continuing longitudinally of the container, until the tear at each side reaches slit 39 nearest to the tab. A substantial body portion of the tongue 3| extending alon thesetwo slits, is thus freed, and lifts out of the fiap30 without resistance by continued pull as described, until uns evered material at the lower end of the same two or uppermost slits 39 opposes the further lifting of the tongue. Continued 1ongitudinal pulling of the tab then causes the shearing of the outer (lower) extremities of the short ribbon-like portion 4| between the first and second slits. Before this shearing occurs, however, the ribbon-like portions permit a separation movement of the tongue ll therebelow away from terial is repeated at the lower or outer ends of the successive slits until, at the one nearest the bottom of the package, the final longitudinal shear, indicated at 42 in Figure 4, reaches the bottom crease at 2911. By reason of the slight separation movement of the body of the tongue 3| from the back wall 25, the body of the tongue is bent less sharply than ribbon part 4|, and shearing of the latter is consequently easier and more definite in direction. The contents of the package serve to separate the front and back walls 2| and 25 of the container, and, as will-be understood, due to the inherent resiliency of the materials from which such bags are customarily formed, there is a stress set up in the walls of the bag by which the lower portions of the walls tend to separate from each other at the line 29.
As the final tearing occurs and the tongue 3| reaches the extended position shown in Figure 7, the stress in the material of the container as mentioned will cause its sides at th opening to spring apart, leaving the contents free to fall, substantially as indicated. opened in this manner it will have the appearance and arrangement of parts shown in Figure 5.
In prior bags of this general kind, where the projection of the back wall downward beyond the line of crease remains attached at the sides to the front side portions or tongues, it tends to be moved to an angle to the ,mean plane of the package, thus acting as a stiffening flange which prevents free bending of that side of the opening, and opposes separation of the walls, and also after a certain amount of the contents has fallen from the package, the inherent resiliency of the material causes it to tend to close upon the remainder of the contents, so that the latter is opposed in its movement from the package; this objection being overcome by the construction and arrangement above last described in my invention.
It will be seen that by the utilization of the line of perforations or slits 38 in the relation and arrangement shown, it is made possible .0 use an opening tongue separable by this means without liability of the contents of the package escaping through the perforations. It will also be noted that by the use of the slits arranged as described, the weakening of the tongues 30 for thepurpose of severance is ample, yet the paper is not so weakened againstbending that it will be likely to crease or to bulge at the line of slits, and the tongue will lie fiat against the back wall of the envelope and maintain a complete seal at the crease 2!|a. In the manipulation of the ackage for opening after starting the tearing out of the tongue 3|, it maybe held in inverted position, as in Figure 3a, with one hand grasped around the container while the tongue 3| is pulled longitudinally upward, after which the contents may be poured from the open end of the container as found most convenient.
When the bag is aseaecr ticed, but if they are inclined as indicated, and if the upper ones in each series stop at their lower ends on lines at right angles thereto and across the upper ends of the slits next below, it will be apparent that there will be a greater amount of material in the tongue opposing the sharp bending of the sheet material at the point of shearing on each side, and consequently the bending of the paper will not be as sharp as in the ribbon-like parts ll when opening is effected as described. But'the shearing will still occur effectively ordinarily if the pull on the tab is applied longitudinally of the package, the sheer then extending longitudinally, and intersecting the next slit below near the upper end of the latter.
But if the pull on the tab should be exerted in a direction at a considerable angle to the longitudinal axis of the package toward one side edge or the other at the lines 24, there would be a tendency for the tear to extend into the body of the tongue 3| at the side opposite the lateral direction of pull on the tab, instead of leading into the next lower slit 39. A considerable variation from an exactly longitudinal pull on the tab will be accommodated by stopping the proximal ends of mutually adjacent slits on a line at right angles to the slits, but by forming the ribbon-like parts 4|, all uncertainty is eliminated, and in ad- .dition, the more effective shearing is accomof separation, extending in a direction or directions having a substantial component of the direction in which shear is to occur (or, in other words, the direction of pull applied to the parts to be separated), is a material factor in preventing mis-directed shearing, and eliminates such failures. When coupled with the lapped arrangement of the mutually adjacent ends of the slits, there is still greater certainty of definite removal of the complete area defined by the series of slits. The direction and arrangement of the slits is also material in enabling the use of an exceptionally small number of slits and the wide spacing to afford ribbon yarts 4| of such substantial dimensions that likelihood of casual breakage of the package at the perforations is greatly minimized. The small number of slits as used is also afactor in assuring a heater shape to the torn-out part, as well; as contributing to the rapidity and certainty of the opening operation.
The bag as described is adapted to beused in the conventional way in bag-filling machines where a large quantity of the containers are set in a bag-feeding box, in close packed relation and erect position, with the top tongues or flaps 21 extending upwardly without being creased or gummed. The machine introduces a charge into the open upper end of the container, and
creases the bag at the proper line, as well as applying gum on the closing flap 21, as indicated at 43,, after which the closing tongue or flap thus formed is folded and squeezed so as to effectively seal the package.
Should the lapping of the slits 39 not be prac- 7 I claim:
1. A container of the character described comprising a blank of sheet material having a front wall and two side flaps lapped to form a back wall, their lower edges forming a line across the container. a bottom flap extended integrally from the lower edge of said front wall longitudinally beyond said back wall and folded upwardiy at the said lower edges of the back wall, fillets integral with the side and bottom flaps formed at each side of the junction of said bottom flap and said front wall and extended laterally from the lines 01 fold of the side flaps and longitudinally beyond the line 01 fold of the bottom flap, said bottom flap having respective series of perforations at each side defining a substantially triangular centrati tongue having a broad base coincident with the base of the flap and a narrow portion at the extremity of the flap, said flap including integral lateral parts outwardly of and adjacent the narrower part of said tongue, an adhesive in permanent securin engagement between said lateral parts and the s being of a material structurally weaker than the a sheet material of said blank.
2. The structure of claim 1 in which said strip' of material between the fillets is of a thickness substantially the same as that of the fillets.
GEORGE E. GOFF.