US2756923A - Latch formed by superimposed sheets - Google Patents

Description

y 1, 1956 e. w. POPPE LATCH FORMED BY SUPERIMPOSED SHEETS Filed Feb. 1, 1954 INVENTOR. 6500s: it. flop/ 5 BI Ilia/7m,

ATTORNEYS.

LATCH FORMED BY SUPERIMPO'SED SHEETS George W. Poppe, Stroudsburg, Pa., assignor to Equitable Paper Bag Co. Inc., Long Island City, N. Y., a corporation of New York Application February 1, 1954, Serial No. 407,231 4 Claims. c1. 229-77 This invention relates to a latch formed by superimposed sheets of flexible material. The invention is particularly adapted for incorporation in a paper bag, envelope or the like, in which case the superimposed sheets are provided by the parts of the article which are fastened together by the latch. For example, one wall of a bag or envelope may be extended to form a flap which folds down over the other wall, in which case the flap would provide one of the superimposed sheets while the other would be provided by the two walls of the bag which would function cooperatively.

One of the objects is to provide a latch construction which is suitable for application to paper bags, envelopes and the like, which may be created only by forming appropriately contoured lines of severance through the parts to be fastened together, and which provides an easily manipulated latch. Another object is to provide such a latch in a form that will have an attractive appearance. Other objects may be inferred from the following disclosure of specific examples of the invention.

These examples are illustrated by the accompanying drawings in which:

Fig. 1 is a perspective view showing a preferred form of the invention as incorporated in a paper bag or envelope having a flap fastened closed by the new latch;

Fig. 2 shows the top portion of Fig. 1 as the construction appears prior to latching and with the flap fully opened;

Fig. 3 is a cross section taken on the line 3-3 in Fig. 1;

Fig. 4 shows the upper portion of a bag or envelope having a fiap closed by a modification of the invention; and

Fig. 5 shows the construction of Fig. 4 as it appears when the flap is opened and prior to engagement of the new latch construction.

In the form shown by Fig. 1 the bag or envelope has a front wall 1 and a back wall 2, the back wall being extended to form a flap 3 which may be folded down over the front wall 1. All of the parts of this article are formed from sheet material such as paper or the like. This material has a certain amount of elasticity and stiffness when it is not bent excessively. The constructional details of the bag or envelope, such as the manner in which it is folded from sheet material, seamed, bottomed, and similar details, is unimportant insofar as the present invention is concerned.

The two walls 1 and 2 may be considered as a single sheet, the flap 3 constituting a second sheet, these sheets being superimposed when the flap is folded downwardly.

According to the invention, the walls 1 and 2 have an nited States Patent the curve 6 is formed so that when the flap 3 is closed, or folded downwardly, the curves 4 and 6 curve in the same direction. Also, the central portions 5 and 7 of the respective curves mutually register when the flap is closed. However, the curves 4 and 6 have different degrees of curvature respectively and, therefore, the curved lines of severance respectively diverge from each other in both directions from their central portions to their opposite end portions. This results in the mutually adjacent ends of the two curves being offset from each other transversely with respect to the bag or envelope.

The line of lesser curvature, which is the line of severance 4 in the drawings, has a return portion 8 which extends back to the line of greater curvature, which is the line 6 in the drawings, at each of the end portions of the line of severance 4. The line of severance of greater curvature 6 defines oppositely pointing tabs 9 which may be elastically displaced to form openings 10, and the line of lesser curvature 4 defines oppositely pointing tabs 11 having shoulders 12, defined by the return portions 8, and which may be pushed through the openings 10 by elastic displacement of the shoulders 12. This action .is carried out when the sheets are superimposed and ready to be fastened together, and the action may be effected simply by pushing the tabs 11 towards the tabs 9.

1 It is to be noted that the tabs have mutually registered S-curved line of severance 4 formed therethrough and this modified latch construction.

hinging base lines, indicated by the broken line 1313 in the drawings, these hinging base lines extending straight between the end and central portions of the lines of severance 4 and 6, in each instance.

. The line of greater curvature 6 continuously curves reversely between its end portions. It may take the form of two semi-circles joined to form an S-curve. The line of lesser curvature 4 has its previously mentioned return portions 8 extending back to the line of greater curvature 6, when the sheets are superimposed, at both ends thereof substantially straight and in alignment with the base lines indicated by the broken line 1313. Excepting for these return portions, the line 4 also continuously curves reversely between its end portions, the desired S-curve in this instance being also formed by two appropriately joined semi-circular lines of severance.

In the modification shown by Figs. 4 and 5 a half S-curve latch construction is provided. Thus the line 4a is only a semi-circle, one end of this line representing the central portion 5a of the S-curve. The curve 6a carries along this idea, and it is to be noted that the curve 4a has thereturn portion 8a of the full S-curve. The main difference is that the latching action only occurs when the flap is pulled straight away from the walls of the receptacle, or at an angle directed towards the latters center. A pull on the flap directed away from the central portion of the bag or envelope might unlatch Therefore, when this modified construction is used it is preferable to incorporate both halves of the previously described S-curve construction.

As is shown by Figs. 4 and 5 the two halves of the S-curve construction may be changed so that the tabs provided both point upwardly. This is not necessary but it does provide a better appearance. However, it is quite preferable to arrange the two half S-curve constructions so that the shoulders 12a point in opposite directions transversely to the bag or envelope. By doing this a secure latching elfect is obtained because the two latch constructions best resist unlatching in opposite directions and, therefore, mutually cooperate to fasten the flap closed in a secure manner regardless of the direction of force supplied to open the flap.

In the modified form the parts which correspond to those of the full S-curve form are given similar numerals in conjunction with the letter a. The mode of operation is similar in both cases but the full S-curve construction provides the maximum security in all instances.

This new latch construction has the great practical advantage that one of the tabs, providing the latch shoulder, may be made considerabl-y wider than the hole through which it is pushed by displacement of the corresponding tab of the other sheet. The curved shapes permit the shoulder to elastically deform and to then snap behind the other sheet after the shouldered tab is pushed through the opening. In the case of the full S-curve construction the shouldered tabs may be made considerably wider than the openings through which they are pushed. This advantageous feature cannot be provided so effectively by prior art constructions because in the latter it is very easy to tear the paper or other material when causing locking action of the locking tabs. Anotheradvantage of the present invention is the obviously attractive-appearance that results from its use. The construction is inexpensive because it may be produced merely by die cutting the sheets to provide the appropriate curves disclosed hereinabove.

I claim:

1. A latch for abag having a front and back walls and a flap. connecting with one of said. walls and folded down over the other of said walls, said walls and flap being made of elastically flexible material and said walls together forming one sheet and said flap being superimposedthereon and forming another sheet, said sheets having linesof severance formed therethrough respectively, all of said lines being curved in the same direction :and having different degrees of curvature respectively, all of said lines-extending between interspaced locations and all of said. lines: being mutually registered substantially-at one of said locations and respectively diverging from each other while e-xtcndiugtosthe other ofsaid locations and at the latter location the line oflessercurvaturelhaving a re-l turn portion extending back to the line of greatercurvature, the latter line defining a tab which maybe displaced to form an, opening and said line of lesser curvature defining a tab having a, shoulder,.defined bysaid return portion of this line, and, which may be pushed through .saidopening y las ic pla ement of said shoulder, the latter latching wi h the one f sai heet iuwh ebsaid opening isformed h n p s e ue said open ng.

2.. A lat h f r h s ha inat cr t. and back Walls'and a p c ing- W t 9 16 at saidwalls and. toldecldown ver he other f i w lls. Said-Wall encl an bei made. of elastically fleXible m ltrial and said, walls to.- e hsrterm ngn sheetand said flap being superirrn pe edthereon an forming-an th r s eet, sai sheet having lines f,- e r nce f rmedths ethmnshresp ctively. all, of sai 'lines ei gcur ed in tbe same dir cti n and having different degrees .ofcurvature, respectively all of said lines extending between interspaced locations, and all of saidline eing mu a y gi tere substanti l y at one. of said locations, and respectively-diverging frorn eaeh other while, extending to. the other of said locations. and at the l tter location e'line or les er c at re h ving a return portion extending back to the lineof greater urva u he lat r line d fining a b W ich aybe displaced to form an opening and said line of lesser curvature defining a tab having a shoulder, defined by said return portion of this line, and which may be pushed through said opening by elastic displacement of said shoulder, the latter latching with the one of said sheets 1n which said opening is formed when pushed through said opening, said tabs having mutually registered hing ing base lines extending straight frorn onfi. Of said loca H to h her in each ns ance, sa d li f gre ter rv u on nu usly tm'rv rig ron me f sa dos a fiapconnecting with one of said Walls and folded down over the other of said Walls, said walls and flap being made ofelastically ,fiexible material and said walls together forming one sheetand said flap being superimposed thereon and forming another sheet, said sheets having lines of severance formed therethrough respectively, all of said lines bein g S-curved in the same direction but having different degrees of curva ture, respectively, all of said lines having central portions which are mutually registered substantially and said lines respectively diverging from each other in both directions from said central portions to their opposite end portions, the line of lesser curvature having-a return portion extending back to said line of greate-rcurvature at each of its said end portions, said line of greater curvature defining oppositely-pointing tabs which maybe displaced to form openings and said line I of; lessercurvature defining oppositely pointing tabs having shoulders, definedbysaidreturn portions of this line, and whichlrnaybe pushedthrough said openings by elastic displacementof said shoulders, the latter latching-with the one .ofsaid sheets in which said openings are formed when pushed through said openings. 1

. .4. A latch for albag having from. and back walls and a flap-conneetingwith .oneof said walls and folded down oventhe Other of said walls, said walls and vflapbeing ma e. .Of elastically:.fiexiblematerial and said. walls to getheIiorr-ningone sheet and saidfiap being superimposed thereon and forming anotherlsheet, saidsheets having lines of severance. tanned therethreugh respectively, all of said lines-beings curved in. the same direction but having difierent degreesofj curvature respectively, .all of said lines havingqeutral portions, which are mutually registered substantially and said lines respectively diverging from each Otherin, bqth glireotions from said central portions to thei OBPQSitQ end pt rti usr the line. of lesser curvature having a rn-Parties xtending back to, ai line or sre terle ve llr at. each ef. i s and en portion said iasr st s Ql W 'L I efining pp sitel pointing tabs which may be displaced to form openings and said line Oi a r cur tur de n n pp sitely PQ ng t b havin shoulders, defined by said return portions of this line, and .1, 2 p l he -through said openings, ,by elastic F p tssm m i ai s ultle e h atter t i w th the one of said sheets in which said openings are formed wheupushed through said openings, said tabs havin mutually registered .hingi lg b se lines extending straight between all of their said portionsineach instance, said line pi, greater. curvature; continuously curving reversely between its saidend portions and said line of lesser curvature-having its, saidretur'n portions extending back to said 1m figie etqurvature at both ends thereof substantially straighrand jn alignrnentwith said base lines, to define sa d tab andotherwi e continuously u ing ,r v ely w n said a d p io s,

Referenges ,Cjtedin the file Qfihis patent UNFEED STATES PATENTS 229,893 Kehr July 13, 1880 1,310,288 Nico; 'July'15, 1919 1,665,035 7 Kleebaueret al Apr. 3, 1928 ,ZJIOQAH Poppe July 30, 1935 2,132,669 Wolf Oct. 11, 1938 52,536,384 Meller Jan. 2, 1951

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