US 3353661 A
Description (OCR text may contain errors)
NOV- 21, 1957 H. MMMMMM No 3353561 .2 eeeeeeeeeee tl Nov. 21, 1967 H MMMMM |No 3,353,661
GE oF PL T L l i 60 i l 82 I l 84 71:) l /62 I Ia f mln Gan w h li ,s b
sN`vENToR= HERCULES MEMB aNo BY= ATToR Y United States Patent Ofifice 33%,061 Patented Nov. 21, 1967 3,353,661 PACKAGE OF PLASTIC BAGS Hercules Memhrino, 1934 Arch St., Philadelphia, Pa. 19103 Filed Nov. 5, 1965, Ser. No. 506,487 Clairns. (Cl. 206-57) ABSTRACT OF THE DISCLGSURE A bag unit comprising a pair of bag pockets that are integrally connected to opposite side edges of a spacer strip by means of interrupted slits, the interruptions in the slits acting as tearable connecting means. When the bags are torn away from the spacer Strip on the slitted lines, the slits define open mouths on the bags. The bags are individually removable from the spacer strip so that the spacer strip can act as a permanent backer in a holder. In this manner, a plurality of overfolded and overlapped bag units can be mounted on a support and thereby constitute a unitary package or assembly from which individual bags can be removed in completed form whenever desired.
This invention relates to plastic bags, and it particularly relates to an improved process for the manufacture of such bags.
Plastic bags, made of polyethylene, polypropylene or similar thermoplastic polyolefins are today used for many packaging purposes not only in the home but in retail businesses as well as in industry. These bags are becoming increasingly popular not only because they are highly air and moisture proof and easy to use but because they are relatively inexpensive and can be easily mass-produced. However, this very fact makes it important to achieve the greatest economy possible in their manufacture since the saving of even a fraetion of a cent per bag results in large savings because of the great number of bags produced.
The large volume of sales of these bags makes for a highly competitive market and, therefore, even a seemingly small saving in the cost of manufacture results in a great competitive advantage.
It is the primary object of the present invention to provide a method and apparatus for making polyolefin bags which results in substantial saving in time and labor and therefore in the ultimate cost of the bags.
Another object of the present invention is to provide packaged units of bags which are specially adapted to the aforesaid lmethod of manufacture whereby the packaged units themselves provide the final step of making the ba-gs, this final step being performed by the consumer.
Other objects and many of the attendant advantages of this invention will be readily -appreciated as the same becomes better understood :by reference to the following description when read in conjunction with the accompanying drawings wherein:
FIG. 1 is a somewhat diagrammatic, fragmentary view showing a tubular strip of polyolefin material being processed to form -bag units.
FIG. 2 is a perspective view of a single bag unit after being folded and prior to being combined with other similar -bag units to form a package unit.
FIG. 3 is a perspective view of a package unit comprising a plurality of bag units such as shown in FIG. 2.
FIG. 4 is a fragmentary perspective view of a package unit, such as shown in FIG. 3, releasably connected to a supporting hanger.
FIG. 5 is a perspective view of a finished bag after FIGS. 3 and 4. v
FIG. 6 is a view similar to FIG. 1 but showing the manufacture of a different type bag.
FIG. 7 is a view similar to FIG. 2 but showing a bag unit made by the process illustrated in FIG. 6.
FIG. 8 is a view similar to FIG. 3 but showing a package unit containing the -bag units of FIG. 7.
FIG. 9 is a somewhat diagrammatic view of a process of making yet another type of bag.
FIG. 10 is a perspective view of a package unit made up of bags formed in the process illustrated in FIG. 9.
FIG. ll is a perspective exploded view of a preferred method of packaging the bags.
Referring now in greater detail to the various figures of the drawings wherein similar reference characters refer to similar parts, there is shown in FIG. 1 a tubular strip 10 of a thermoplastic polyolefin such as polyethylene or polypropylene. This strip 10 is shown as it is passed through a bag making machine. The machine itself is not illustrated since it may be any one of a number of standard -machines wherein a heated sealing and cutting head is intermittently applied to the strip as the strip is passed longitudinally through the machine. The heated head, here shown diagrammatically and designated 12, passes transversely through the thermoplastic Strip 10 and simultaneously severs a portion thereof and heat-seals the severed edge.
In the present method, however, prior to application of the heated head 12, the strip 10 is scored longitudinally by a double line of scoring along its center, these lines of scoring being illustrated at 14 and 16. This scoring can be accomplished in any manner desired, such as by providing appropriate cutting means on the machine, or by cutting the strip manually, or by pre-scoring the strip prior to its insertion in the machine, etc.
The slits in the lines 14 and 15 are identical to each other, each line consisting of alternate relatively short and long slits, so that each long slit is bounded on either end by a short slit. The slits in each line are closely spaced from each other so that only small uncut spaces or nips are provided therebetween.
The head 12 is operated in conjunction with the longitudinal movement of the strip 10 so that it is applied to the strip midway between each parallel pair of small slits in the lines 14 and 16, as shown in FIG. 1. This results in the severing of a bag unit, such as shown at 18.
The bag unit 18, as it comes from the strip, actually consists of two identical portions 20 and 22. Each portion is sealed on three sides due to the fact that the unit is formed from tubular material so that the ends are closed, while the sides are sealed by the heated head 12. On the fourth, or inner side, each portion is defined by a slitted edge, respectively designated 24 and 25. These slitted ed-ges are separated from each other by a spacer portion 28. The slitted edges 24 and 26 form open ends except for the nips 30 and 32 respectively. These nips keep the two portions 20 and 22 connected to each other.
The bag units 18 are then separately folded along the Iongitudinal center of the spacer portion 28, as shown in FIG. 2. Reinforcements, shown at 34, are then applied to the spacer portion 28, one adjacent each nip 30 and 32.
,The reinforcements extend through the folded spacer portion so that each provides a reinforcement for a corresponding pair of nips 30 and 32. These reinforcements are preferably welds formed in the thermoplastic material itself, but may also take the form of staples, cords, plastic or rubber strips, or any other feasible means.
A number of the bag units shown in FIG. 2 are then overfolded, one over the other, and a backer 36 is Secured around the spacer portions (as shown in FIG. 3) to form a package unit 38. Staples, welds or the like, shown at 40, are used to fasten the backer 36 in place.
The package unit 38 can be used in any manner desired. One preferred manner is to removably secure it to a hanger, such as shown at 42 in FIG. 4. This hanger 42 may be constructed of metal, plastic, wood or .anyother 'desirable, relatively rigi'd material, and is secured on a Wall or other supportngsurface by'any desirable means such'as adhesive, screws, nails, rivets, etcThe hanger has ahook portion 44 .an'djthe packageunitf38-is Secured to the hanger by passing the mating center .portions of'the slits 24 vand'26over'the hook portion 44 in the manner shownin FIG. '4.
While the bag unitsl 18 remain'in'the package units..38, the .bags, as such, do notlvyet exist. However, whena bag is desired, the outer .bag .unit portion 20 or 22 -is grasped and pulled away'frorn the package. This breaks the nips 30 or` 32 and what is pulled away is'a complete bag'46, shown in FIG. 5.
In the abovemann'er, two'bags, each constituting'one lportion of unit 18, are formed simultaneously and with .a singleV motion of the sealing. andsevering headf12. At .the same time, the two bags..are held together so'that'they are more easilyhandled andpackaged than individual bag's. Furthermore, they are so connected that'they4 are easily dispensed when packaged.
.Thebags formed by .the method described abovehave anopen end definedby apair of. edges in the same plane. Althoughsuch bagsare e'fiicient for all theirpurposes, it issometimesdesirable to have ,abag that is'provided with a lip at its open end to perrnit easy grasping' both forpulling the .bagaway from the Apaelrageunitand, for opening the .bag itself. Such a lip is provided by makingonee'dge at the openend lowerthan the other. i
The present method canibe used forma-king bags with lipsas, illustrated. in .-FIGS. 6, '7 and 8. 'InFIG.6, .there is shown aluhular .StripV 50 .that is .provided .with alongitudinally=extending1slot 52..at its center. The slot 52,-which is defined by oppositely-disposed .straightlparallel edges,is provided vonly on the uppersurface 54 of;thertubu1ar strip, the bottom .surface56being nncnt. This ,slot 5,2, maybe pre-formed in, the .tubular stock..or.it. may be. obtained by providingknife means on the .machine or it may .evenbe formed ,by hand with a razoredge orthe like.
The tubular strip 50, with theslot 52 in.its.11pper su'r- `face, isrthen treated inthe same.manner-as:the;strip in FIG. :1, except -thatfthe lines .of .scoring, .indicated at.58 Vand 59, are impressed-onlyinthe.bottom-surface-framed -within the rlongitudinal .slot 52. The heatedsevering 1and sealingfhead 76,0 .is similar to the head .12 .and similarly -severs a bag unit'62witheachstroke.
The bag unit62 comprises ltwo bagfport-ionsrfltand-.- eachrof which .has anfinnenedge, as -at68.and .7..0 respectively,:thatfstops `short of the. respective score: lmes :722and 74. These'score lines .l-aterformthe edge. of the :rear .walls of'thebags.
VThe Vbag lunit .62 is -thenfo'lded vvaslin. FIG. 1,;s1m1la-rly -to .the bagunit l18. -I-Iowever,:in-this'case only :the .rear wall 56 serves as the-hinge means. A reinforcement 75 :such 1as a-weld,-staple, orthelike, is provided r-adiacent each v,nip Vin .the 1score.lines,.simiarly to those shown .m EIG.,2.
A.v number of bagrunits .62 .are lthen. overfoldedione .over .the other and provided with a backer 76 .similar to .the backer 36 shown .in .FIG. 44, ,the resultiug ,package unit beingdesignatcd18. V
VThe above Vprocess .has been rdescribed With .part1cular relation vto the manufacture of relatively small bags, each Vhaving a length of approximately half the Width of the tubular strip. However, this process can kalso be advan- "tageously used in=themanufacture -of largerbags =hav1ng a length approximately equalto-t-he widthfoffthe tubeThis is -il1ustrated in FIGS. '9 and where the ftubular xstrrp `80 is providedwith'a'single line Jof scoringadjacent -one edge. This line of-scoring, designated 82, is similar to =each linefof'seoring shown in FIGS. -1 and-6in1that itcomprises alternative largel and -smll-slits.
The scored tube is passed under a heated severing and sealing head 84 similar to those shown at 12 and 60. The head 84 severs a bag unit 86 having an openable end defined by the score line 88.
A number of bag units v86 are then assembled, one adjacent the other, into' apackage unit .90 having a backer 92 similar to those shown at 36 and'72.
It is apparent that, if 'desired,.the score lines, such as shown at '-14=and 16, may be off-center relative to the longitudinal axis of the tu-be so that one Operation can result in bags of different,sizes..Furthermore, more than one pair of score lines, such as shown at 14 and 16, can be provided, Whereby4 more than two Vbagsscanbe made in -each Operation of-t-he head 12.
Any of rthe package units described abovemay .be in- :serted in -a .paper bag or the like-constituting-a wrapper, and the backer portionstapled'or otherwise vSecured .to onecend of vthe -wrapper-bag..-A score line may..then.be,provided.. around the'wrapperbag to separateithebottom; por- ,tion thereof from the'upper; portion-towhichfvthebacker -is ``Secured. .This bottom gportion. may then-.be .removedby the :consumer leaving thelower portions of 4thefbag'unit available for graspingThis -is illustratedin FIG. :1 lxwhere .there is:shown-=a package unitj positi'oned within'a :wrapper :bag having -au'upper portion -=102and :aremovable lower portion 104. The backer portionofthe .package unit 100 is staped,':asfat --106,for otherwise Secured, to the inside of theupper portion.102.
The'lower .portion 104 .is Secured tohe uppenportion 102 by a score line and is removable therefrombymerely tearingaround. the .score line.
Obv-iously, many modifications. ofthelpresentinvention arepossible in the light of; the above teachings. Itfis,.therefore, to be understood that .within .thefscope oftheappended claims, the inventionmay.be practicedotherwise .than as specificallyV described.
The invention claimed is:
1. A bag unit comprising at least one paiLof-pockets, .eachpocket beingdefined. by,a frontwall-anda, rear .wall that are sealingly connectedaroundthe entiregperipliery -vof'thepocket except ata month7 portionthereofi-themonth portion of each pocket being dcfined`by.an.interrpted .slt having .-at; leastY one interruption, .fformig..a-nip, rinter- .mediate itslends, the,interruptedslitsof-said pocketsfibeing Vin fopposed positions relati-ve 2to -each .other =and being separated from each other byaspacer portiomsaid .spacer :portion:being--integrally connected-to-,eachof said pockets by :said nips, :said .month portions of :the pockets :being :completely open and unsealed-.except .fen-said mips, -an'd said spacer -portion being .substantiallly Eimperforate .be- Ctween -ts edges defined .by -said.interrupted slits.
.2. Thefbag unit of claim 1 wvhereinreinforcementsare :provided in said-spacenportion fadjacentfeaehfnip.
, 3. vThe bag -unitoffclaimlwherein:saidflrspacergportion .is :provided .with galongitudinal -Vfold [line formiriga Vhinge upon which'thebagportions are overfoldedon'each-iother,
said spacer portiongconstitutingsa baseport-ionand'fsaid f'bag .portions being separable ,,theref-rom1by :breaking :said vmps.
4. The bag unit of claim lacombined withra plurality of other similar bag units to :form .ai-package. unit, fthe .spacer portions of vt.hefbag..units.-beingioverlappedtto,.form
a base portion for said package unit,and:awrapper.bag -enclosing .said i,package ,unit, -said=wrapper .bag having an .upper and a lower portion, said :portionsheing-removably connected to each other, .andsaid baseportion beingse- Vcured to said .upper' portion .of said .wrappcrbag V5. The bagunit vof claim 1 combined wi thaplurality .of other similar .bag units to V.form .a ,package uni,t,.the
Hspacer portions of the bag.unitsbeingoverlapped to form a base portion for said package unit, and .the score'lines of the .bag Vunitsrnating .with ,each other to form acom- .mon slot.
(References en following page) 6 References Cte 3,033,257 5/ 1962 Weber 150-1 MLHIOII 12/1909 ce 206-57 330 464 /EIGGN PT-NTS 2 1916 2 6 58 feat I'ltaln. Whem O 5 384,779 12/1932 Great Britain. 6/ 1925 Lewls 206-57 2/ 1937 Taylor 206-57 THERON E. CONDON, Primary Examiner. 9/1952 Henry 229-69 WILLIAM T. DIXsoN, JR., Examner.