US 3528471 A
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Description (OCR text may contain errors)
Sept. 15, 1970 NN 3,528,471
CARRIER BAGS HAVING HANDLES WITH SNAP-FASTENER LOCKING MEANS Filed April 25, 1959 INVENTOR Emi-l Harfmann rZAw LwQ ATTORNEYS A I United States Patent O 3,528,471 CARRIER BAGS HAVING HANDLES WITH SNAP-FASTENER LOCKING MEANS Emil Hartmann, Zurich, Switzerland, assignor to CTP gldliistries Inc., Brooklyn, N.Y., a corporation of New Filed Apr. 23, 1969, Ser. No. 818,728 Claims priority, application Switzerland, Apr. 25, 1968, 6,154/ 68 Int. Cl. B65d 33/24 US. Cl. 150-3 4 Claims ABSTRACT OF THE DISCLOSURE Snap-fastener type locking means for handles of the type affixed to the mouth of a carrier bag. Stud and recess elements are provided on the opposed handle portions. The stud portion extends through the recess on the opposite handle part and is provided with an overhanging portion which is resilient and deformable and capable of being latched behind a protruding part in the recess on the opposite member. As a result, the two members are locked securely together and quite strongly oppose separation in response to forces tending to separate the bag walls, whereas the handle members are quite readily separable when the two hand-grip portions are prized apart.
BACKGROUND OF THE INVENTION Thermoplastic carrier bags which are provided with a pair of handle members at the opposed bag walls adjacent the rnouth of the bag and with means for snap fastening together the two handle members are now wellknown in the art. Generally, the two handle members each comprise a longitudinal sealing bar and a centrally-disposed looped gripping portion which is integral with the sealing bar.
The sealing strip and/ or the looped hand-grip portion may carry one or more snap fastener elements generally comprising a protruding stud on one part and a mating recess on the other. Each handle is affixed to the bag wall at its mouth by heat sealing the longitudinal sealing strip to the open edge of the bag. Such bags may be frequently re-used and are highly convenient to the user because the bag mouth may be closed to guard against loss of the bag contents and entry of dirt, rain, etc.
One of the problems connected with the use of plastic carrier bags of this general type is that, although the snap fastener means must be of such a type as to readily per-mit opening of the bag by prizing apart the two handle members, the handles should not be readily separable as the result of forces exerted on the bag walls as may result from the carrying of a load of goods in the bag. Thus, it is quite desirable that the locking means on the two handle portions be able to resist quite strongly any tendency to separate the handle portions resulting from opposed lateral forces acting on the bag walls which are connected to the aforesaid respective longitudinal sealing strips.
SUMMARY OF THE INVENTION The invention comprises a snap-fastener type locking means for handles for carrier bags which is readily openable when the two handle portions are prized apart at the location of the looped gripping handles, but strongly resist separation when an equal amount of force is applied on the handles through the bag walls. Consequently, the bag can readily be opened by the user, but will not readily be inadvertently opened as the result of stresses from a load in the bag.
The aforesaid improved resultsare obtained by providing a stud and recess combination in which the stud on 3,528,471 Patented Sept. 15, 1970 one of the handle parts is provided with an overhanging portion which extends into and over a protrusion within the recess of the opposed handle part. The overhanging portion and also the protrusion are in the bottom por tion of the stud-recess combination, i.e. toward the bag walls which are secured to and depend from the longitudinal sealing strip. At the topside of the stud-recess combination, i.e. the side more closely adjacent the looped gripping handle, the stud and recess are both fully curved with no projections nor engaging protrusions. As a result, any separating forces exerted on the two handle parts from above, i.e. forces tending to separate the looped gripping handles, will quite readily result in releasing the snap fasteners; however, forces exerted which tend to separate the longitudinal sealing strips from below cause the above-mentioned protrusion to become quite securely engaged within and behind the overhanging portion of the stud so that there is a strong tendency to resist separation of the stud and recess.
BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a view of a typical carrier bag having thermoplastic bag walls and engageable handle portions which are secured to the bag walls at the mouth thereof;
FIG. 2 is a detailed view of a single one of the stud and recess combinations shown in FIG. 1;
FIG. 3 is a cross-sectional view taken along the section line 33 of FIG. 1;
FIG. 4 is a cross-sectional view of a stud and recess combination according to an alternative embodiment of the invention; and
FIG. 5 is a perspective view of still another embodiment of the invention.
DETAILED DESCRIPTION OF THE INVENTION FIG. 1 illustrates a plastic carrier bag having opposed front and rear bag walls which are formed of a thin-film thermoplastic material. Inside the bag mouth are secured a pair of handle members 12 and 13 each of which comprises a longitudinal sealing strip 14, 15, and a centrally disposed looped hand-grip portion 16, 17. Preferably the handle members 12 and 13 are heat sealed to the bag walls along the respective sealing strips 14 and 15. When the bag mouth is to be closed, the two handle portions 12 and 13 are brought together and are releasably secured together by means of one or more stud-recess combinations 18 which may be located either along the longitudinal sealing strip or in the looped hand-grip portion, but which are preferably located adjacent the region where each looped hand-grip portion joins the longitudinal sealing strip as shown in FIG. 1.
The view of FIG. 2 illustrates in greater detail the combination of a stud and recess for releasably securing two handle portions 12 and 13 together, and FIG. 3 is a crosssectional view of the stud and recess combination of FIG. 2.
One ofthe handle portions 13 is shown as being provided with a stud 19 which is of generally circular crosssection as shown in FIG. 2. The stud is hollowed out at 20 as shown in FIG. 3. The hollowed-out portion has generally the configuration shown by the solid lines in FIG. 2 designated as 21, 22, 23, and 24. The clearance which is provided by hollowing out the stud along the solid lines 22, 23, and 24 provides clearance for the stud over the protuberance 25 which is provided within the recess defined in the opposed handle portion 12. Preferably the protuberance is smoothly curved downwardly toward the entranceway of the recess, but is also provided with an abrupt vertical wall 28 behind which the overhanging lip 27 can readily be engaged. Since the handle portions are principally formed of a rather flexible, deformable plastic material such as polyethylene, it can be seen that when the stud 19 is inserted into the corresponding recess 26 defined in member 12, there will be clearance over the protuberance 25, and it will be necessary only to exert sufficient force to cause the lower lip 27 of stud 19 to pass over the protuberance 25 and be engaged against the back edge thereof, thereby effectively locking the stud in place in the recess.
It can be seen from FIG. 3 that any force applied along the direction of the arrows A to separate the two handle portions 12 and 13 will readily result in slippage of the surface 29 of the recess 26 over the smoothly contoured upper surface 30 of stud 19, and once these surfaces 29 and 30 are free of each other, continued separation of the handle portions 12 and 13 quite readily causes the protuberance 25 to slip out from behind the lower edge 27 of the overhanging lip so that the two handle members are then readily disengaged from each other. On the other hand, if these two members are sought to be separated by lateral forces applied thereto in the direction of the arrows B, then it is found that there is great resistance to such separation since the protuberance 25 is then quite firmly locked behind the overhanging lip 27 of stud 19, and it is found that several times as much force must then be applied to separate the handle members 12 and 13 as is required when forces are applied in the directions of the arrows A.
FIG. 4 illustrates an alternative embodiment of the invention in which the stud 31 is provided with an overhanging lip portion 32 as before but the stud is not provided with a generally hollowed-out portion over its major cross-section. Instead, only a portion of the stud is hollowed out along its bottom portion at 33 so as to provide clearance for the protuberance 34. Otherwise, the stud and recess combination of FIG. 4 operates in much the same way as that of FIGS. 2 and 3.
In the embodiment of FIG. 5, the stud is hollowed out, with the hollowed-out portion being generally circular, but leaving an overhanging lip portion 35. The recess is again provided with a protuberance 36 which can engage with the lip 35 to restrain separation of the two handle portions by lateral forces applied along the bottoms of the respective handle members. In the embodiment of FIG. 5, the protuberance is illustrated as being generally located within the recess, and more closely toward the opposed handle portion than is the case in the embodiment of FIGS. 2 and 3, and the embodiment of FIG. 4.
Although the stud and recess of the embodiments disclosed herein are shown to have a generally cylindrical configuration, this is not essential, and they may very well have different configurations such as an oblong or irregular cross-section.
What I claim is:
1. In a carrier bag of the type having opposed bag walls and a pair of handle members formed of a flexible deformablematerial each secured to a bag wall at the mouth of the bag and with each handle member having a portion which is sealed to a bag wall and having also an integral hand-grip portion, the improvement which comprises:
snap-fastener locking means for said handle members comprising a stud on one handle frictionally and releasably engaging within a recess formed in the other handle member,
said stud being of generally cylindrical configuration and projecting laterally outwardly of said one handle member,
said recess having a protuberance therein in the circumferential portion thereof which is most closely adjacent the location at which a bag side wall is secured to the relevant handle member,
said stud having a part of its cylindrical body portion removed from its point of juncture with the respective handle member axially therealong to a point near its remote end to thereby provide an overhanging lip at a said remote end which passes over and effectively locks behind said protuberance when said stud is fully inserted into said recess,
said body portion which is removed providing clearance for said protuberance,
whereby lateral forces on said bag walls in a direction tending to separate said handle members are strongly resisted by the locking effect of said protuberance and overhanging lip whereas exerted on the hand-grip portions of said handle members readily result in separation of said handle members.
2. The carrier bag of claim 1 in which both said stud and said recess are of generally circular cross-section.
3. The carrier bag of claim 1 in which said protuberance is smoothly curved axially along said recess so as to protrude with increasing depth into said recess in the direction of insertion of saidstud.
4. The carrier bag of claim 3 in which the curved surface of said protuberance terminates abruptly in a surface which is substantially transverse to the axis of said recess to provide thereby a surface against which said overhanging lip can abut when said stud is fully inserted into said recess.
References Cited UNITED STATES PATENTS DAVID M. BOCKENEK, Primary Examiner U.S. Cl. X.R. --12; 22954