Carrier stock with tear-open tabs

Abstract: Carrier stock (10) is formed from a single sheet of resilient polymeric material, such as low density polyethylene, for machine application to substantially identical containers (12). The stock (10) is severable to form individual carriers (20) with container-receiving apertures (14), as defined by band segments, which include outer segments (22) formed with tear-open tabs (30). Each tab (30) and preferably the outer segment (22) have multiple slits (32,40,50,52), which are arranged to define tearable bridges (42,54,56,58) that can be easily torn by a user pulling on such tab (30), whereby the outer segment formed with such a tab (30) can be easily severed to release a container from the aperture (14) bounded partly by such a segment (22).

Description: This invention pertains to carrier stock for machine application to substantially identical containers. This invention pertains, more particularly, to carrier stock that is severable to form individual carriers with separate apertures to receive the individual containers. Tear-open tabs are provided, which enable the containers to be removed. Typically, carrier stock with individual container-receiving apertures for machine application to substantially identical containers is formed, as by die-cutting, from a single sheet of resilient polymeric material, such as low density polyethylene. An example of such carrier stock is disclosed in US-A-4,219,117. Various attempts have been made to provide such carrier stock with tear-open capability. An example of particular interest is disclosed in US-A-4,064,989. As disclosed in US-A-4,064,989, outer band segments of such carrier stock are formed with tear-open tabs, which extend from outer band segments. A slit, which is associated with each tab, extends at an acute angle to a line drawn to a base of such tab. An arrow is impressed on each tab so as to indicate, to a user, in which direction to pull such tab so as to sever the outer segment formed with such tab. In actual experience with such stock, it has been found that if the user pulls in a wrong direction there is some risk of failure due to a tab being torn away without the outer segment being torn through, or due to the outer segment exhibiting excessive resistance to being torn through. A recent example of an attempt to provide carrier stock with tear-open capability is disclosed in US-A-4,925,020. Older examples are disclosed in US-A-2,997,169, US-A-3,038,602, US-A-3,086,651, US-A-3,504,790, and US-A-3,721,337. There remains, however, a need, to which this invention is addressed, for an improved carrier stock with tear-open capability. According to this invention a carrier stock for machine application to substantially identical containers, the stock being formed from a single sheet of resilient polymeric material and being severable to form individual carriers with separate apertures to receive the individual containers, the stock being formed for each individual carrier with integrally joined band segments defining the separate apertures, the segments including outer segments extending in a generally longitudinal direction when the stock is unstressed, each outer segment being formed with a tab which extends in a generally transverse direction from such outer segment when the stock is unstressed, and which provides a tear open feature; is characterised in that each tab is slit to define a first slit, which extends in a generally longitudinal direction when the stock is unstressed, and a second slit, which extends in a generally transverse direction when the stock is unstressed. Preferably, the separate apertures are arranged in two longitudinal rows. It is also preferred that each tab extends into one of the separate apertures when the stock is unstressed. The first slit of each tab may have an open end at the outer edge of such tab and a closed end. Alternatively, the first slit of each tab has one end adjacent to but spaced from the outer edge of such tab so as to define a frangible bridge between such end of the first slit and the outer edge of such tab. The second slit may be spaced from the first slit so that a frangible bridge is defined between the first and second slits. Alternatively, the first and second slits may be sections of a continuous slit, which may comprise a curved slit connecting the first and second slits. It is a preferred feature that the first and second slits of each tab are arranged so that an imaginary line extending in a generally longitudinally direction from the first slit of such tab intersects the second slit of such tab. Thus, a portion of the second slit extends on each side of the imaginary line, when said stock is unstressed. In a preferred arrangement, each outer segment is slit to define third and fourth slits, as described below. In considering the third and fourth slits, it is convenient to refer to each outer segment as having first and second edges with the first edge merging with the outer edge of the tab extending from such outer segment. Each of the third and fourth slits extends in a generally longitudinal direction when the stock is unstressed. The third and fourth slits of each outer segment are arranged so that a frangible bridge is defined between such third slit and the second slit of the tab extending from such outer segment, so that a frangible bridge is defined between such third and fourth slits, and so that a frangible bridge is defined between such fourth slit and the second edge of such outer segment. The slits associated with each tab are arranged so that the outer segments are not weakened significantly but so that the frangible bridges can be easily torn by a user pulling on such tab, whereby the outer segment formed with such tab can be easily severed to release a container from the aperture bounded partly by such outer segment. There is minimum risk of failure due to such outer segment breaking in application machinery, or due to such tab being torn away without tearing through such outer segment. At least in the preferred arrangement, there is minimal risk of failure due to such outer segment exhibiting excessive resistance to being torn through. Herein, references to slits in the carrier stock are intended to refer to scorings, or lines that are not cut entirely through the carrier stock, as well as to those that are cut entirely through the carrier stock and to slits defined by plural perforations. Particular embodiments of carrier stock and packages with it will now be described with reference to the accompanying drawings; in which:- Figure 1 is a perspective view of a package comprising six identical containers and a carrier; Figure 2 is a plan of a carrier; Figure 3 is an enlarged, fragmentary detail showing a representative one of a plurality of tear-open tabs; Figure 4 is an analogous, fragmentary detail showing an alternative tear-open tab; Figure 5 is an analogous, fragmentary detail showing a simplified tear-open tab; and, Figure 6 is an analogous, fragmentary detail showing a further tear-open tab. As shown in Figures 1 and 2, carrier stock 10 for machine application to substantially identical containers 12 constitutes a preferred embodiment of this invention. Such stock 10 is formed with separate apertures 14 to receive the individual containers 12. The carrier stock 10 is severable along transverse lines L , to form individual carriers 20 (one shown) that are substantially identical. As shown in Figure 1, the containers 12 are beverage cans of a type used commonly for beer, soft drinks, and other beverages. Also, each container 12 has a chime 16 at one end, which is provided with a pull tab 18. This invention is not limited, however, to usage with such cans but is useful with cans, bottles, and other containers of various types. In Figure 1, a package is shown, which comprises six such containers 12 and one such carrier 20, as severed from such stock 10. While the carrier 20 is shown to be directly adjacent the chimes 16, this invention is not limited to this location on the containers 12. This invention contemplates that the carrier 20 may be positioned downwardly on the side walls of such containers. In Figure 2, one such carrier 20 is shown in an unstressed condition. The carrier stock 10 is formed in an indeterminate length, as by die-cutting, from a single sheet of resilient polymeric material. A preferred material is low density polyethylene. A preferred thickness for such stock 10 in an unstressed condition, if low density polyethylene is used, is about 0.4mm (16 mils). The carrier stock 10 is formed, for each individual carrier 20, with integrally joined band segments defining six separate apertures 14. As shown in Figure 2, such apertures are in a rectangular array with longitudinal rows and transverse ranks, namely two longitudinal rows and three transverse ranks. The band segments include outer segments 22 extending in a generally longitudinal direction when such stock 10 is unstressed. It is a characteristic feature of the preferred embodiment shown in Figures 1, 2, and 3 that each tab 30 is slitted so as to define first and second slits described below. Each outer segment 22 is formed with a tear-open tab 30 extending in a generally transverse direction when the carrier stock 10 is unstressed. Such tab 30 extends from a mid-portion of such outer segment 22. Preferably, as shown, each tab 30 extends inwardly, into one of the separate apertures 14, when such stock 10 is unstressed. Alternatively, however, each tab 30 may extend outwardly when such stock 10 is unstressed. The first slit 32 of each tab 30 extends in a generally longitudinal direction when the carrier stock is unstressed. Such slit 32 has an open end 34 at an outer edge 36 of such tab 30, as shown, and a closed end 38. The second slit 40 of each tab 30 extends in a generally transverse direction when the carrier stock 10 is unstressed. The second slit 40 is spaced from the first slit 32 so as to define a frangible bridge 42 between the first and second slits. The first and second slits of each tab 30 are arranged so that an imaginary line extending in a generally longitudinal direction from the first slit 32 intersects the second slit 40. Thus, as shown, a portion of the second slit 40 extends on each side of the imaginary line when the carrier stock 10 is unstressed. Consequently, as the frangible bridge 42 is torn by a user pulling on such tab 30, there is minimal risk that part of such tab 30 will be torn away from the remainder of such tab 30 or that such tab 30 will be torn away from the outer segment 22 formed with such tab 30. Continued pulling force will be directed substantially transversely of the outer segment 22 as a result of the orientation of the second slit 40. Since the band segments including the outer segments 22 are tensioned by application machinery (not shown) when the carrier stock 10 is applied to the containers 12, it is important that the second slit 40 of each tab 30 does not weaken the outer segment 22 formed with such tab 30. Thus, the second slit 40 of each tab 30 extends approximately to but not substantially beyond an imaginary line where such tab 30 merges with the outer segment 22 formed with such tab 30, and along which such tab 30 tends to fold, as shown in Figure 1, when the carrier stock 10 is applied to the containers 12. It is a characteristic feature of the preferred embodiment shown in Figures 1, 2, and 3 that, in a region near each tab 30, each outer segment 22 is slitted to define third and fourth slits described below. In considering the third and fourth slits, it is convenient to refer to each outer segment 22 as having a first or inner edge 44 divided into separate portions, one on each side of the tab 30 extending from such segment 22, and as having a second or outer edge 46. The first or inner edge 44 merges with the outer edge 36 of such tab 30 and tends to coincide with an imaginary line along which such tab 30 tends to fold, as shown in Figure 1, upon machine application of the carrier stock 10 to the aforementioned containers. Each of the third and fourth slits of each outer segment 22 extends in a generally longitudinal direction when the carrier stock 10 is unstressed. Consequently, such segment 22 is not weakened substantially by its third and fourth slits and does not tend to break when tensioned by application machinery (not shown) used for machine application of the carrier stock 10 to the aforementioned containers 12. In each outer segment 22, the third slit 50 is closer to the first or inner edge 44 of such segment 22, and the fourth slit 52 is closer to its second or outer edge 46. Moreover, the third and fourth slits are arranged so that an imaginary line extending in a generally transverse direction from the second slit 40 of the tab 30 extending from such segment 22 when the carrier stock 22 is unstressed intersects the third slit 50, approximately at a right angle, as shown, but does not intersect the fourth slit 52. As shown, the first slit 32 of such tab 30 and the fourth slit 52 of such segment 22 are on opposite sides of the imaginary line mentioned in the preceding sentence. The third and fourth slits of each outer segment 22 are arranged so as to define a frangible bridge 54 between the third slit 50 of such outer segment 22 and the second slit 40 of the tab 30 extending from such outer segment 22, a frangible bridge 56 between such third and fourth slits, and a frangible bridge 58 between the fourth slit 52 of such outer segment 22 and the second or outer edge 46 of such outer segment 22. The frangible bridges defined by the first, second, third and fourth slits are arranged in a longitudinally staggered series, as shown. Elements similar to elements designated by unprimed reference numbers in Figures 1, 2, and 3 are designated by primed reference numbers in Figure 4, by double-primed reference numbers in Figure 5, and by triple-primed reference numbers in Figure 6. The alternate embodiment shown in Figure 4 is similar to the preferred embodiment shown in Figures 1, 2, and 3 except that the first slit 32' of each tab 30' extending from each outer segment 22' is closed at each of its ends 34', 38', and is spaced from the outer edge 36' of such tab 30' so as to define a frangible bridge 60, between the end 34' closer to such edge 36' and the first slit 32'. The second slit 40' of each tab 30' is similar to the second slit 40 of each tab 30. The third slit 50' of each outer segment 22' is similar to the third slit 50 of each outer segment 22. The fourth slit 52' of each outer segment 22' is similar to the fourth slit 52 of each outer segment 22. The simplified embodiment shown in Figure 5 is similar to the preferred embodiment shown in Figures 1, 2, and 3 except that the third and fourth slits are omitted. The first slit 32'' of each tab 30'' extending from each outer segment 22'' is similar to the first slit 32 of each tab 30. The second slit 40'' of each tab 30 is similar to the second slit 40 of each tab 30. As a possible modification (not shown) the first and second slits may be similar to the first and second slits of the alternate embodiment shown in Figure 4 and described above. A simplified embodiment (not shown) is contemplated that is similar to the preferred embodiment shown in Figures 1, 2, and 3 except that the fourth slits are omitted. The first, second, and third slits are similar to the first, second, and third slits of the preferred embodiment shown in Figures 1, 2, and 3 or to the first, second, and third slits of the alternate embodiment shown in Figure 4. As a possible modification (not shown) the third slits may be centred between the inner and outer edges of the outer segments. The further embodiment shown in Figure 6 is similar to the alternate embodiment shown in Figure 4 except that the first and second slits of each tab 30''' are sections of a continuous slit. As shown in Figure 6, the first and second slits of each tab 30''' are connected by a curved, substantially arcuate section 62''' of the continuous slit. The curved section 62''' extends between one end 38''' of the first slit 32''' and one end 64''' of the second slit 40'''. A frangible bridge 60''' is defined between the other end 34''' of the first slit 32''' and the outer edge 36''' of such tab 30'''. The second slit 40''' extends approximately to but not substantially beyond an imaginary line where such tab 30''' merges with the outer segment 22''' formed with such tab 30'''. The third slit 50''' of each outer segment 22''' is similar to the third slit 50 of each outer segment 22. The fourth slit 52''' of each outer segment 22''' is similar to the fourth slit 52 of each outer segment 22. In the further embodiment shown in Figure 4, tear-away force exerted by a user on each tab 30''' will be first directed parallel to the longitudinal direction of the carrier stock and, then, continuously directed perpendicularly, in a transverse direction relative to such stock, so as to insure that rupture occurs across the outer segment 22''' formed with such tab 30''' rather than across such tab 30'''. In each of the illustrated and contemplated embodiments, the slits are arranged so that the outer segments are not weakened substantially, but so that the frangible bridges can be easily torn by a user pulling on the tear-open tabs. The outer segments can be easily severed so as to release the containers from the apertures bounded partly by the outer segments. In each of the illustrated and contemplated embodiments, there is minimal risk of failure due to any outer segment breaking in application machinery used to apply the carrier stock to the containers. Moreover, there is minimal risk of failure due to any tear-open tab being torn away without the associated outer segment being torn through. In the preferred embodiment, and in the contemplated embodiments including third slits but not fourth slits, there is minimal risk of failure due to any outer segment exhibiting excessive resistance to being torn through. Other aspects of the present invention are described in the following numbered clauses:- 1. Carrier stock for machine application to substantially identical containers, said stock being formed from a single sheet of resilient polymeric material and being severable to form individual carriers with separate apertures to receive the individual containers, said stock being formed for each individual carrier with integrally joined band segments defining the separate apertures, said segments including outer segments extending in a generally longitudinal direction when said stock is unstressed, each outer segment being formed with a tab extending in a generally transverse direction from such outer segment when said stock is unstressed, each tab extending into one of the separate apertures when said stock is unstressed, each tab having an outer edge, each outer segment having an outer edge and an inner edge with the inner edge merging with the outer edge of the tab extending from such outer segment, each tab and each outer segment being slitted so as to define a series of frangible bridges between the outer edge of such tab and the outer edge of such outer segment. 2. The carrier stock of clause 1, wherein each outer segment is slitted so as to define a first slit, which extends in a generally longitudinal direction when said stock is unstressed and which has an open end at the outer edge of such tab and a closed end, each tab being slitted so as to define a second slit, which extends in a generally transverse direction when said stock is unstressed and which is intersected by an imaginary line extending in a generally longitudinal direction from the first slit of such tab so that a portion of the second slit extends on each side of the imaginary line when said stock is unstressed. 3. The carrier stock of clause 2, wherein each segment is slitted so as to define a third slit, which extends in a generally longitudinal direction when said stock is unstressed so that a tearable bridge is defined between the third slit and the second slit of the tab extending from such outer segment, as to define a fourth slit, which extends in a generally longitudinal direction when said stock is unstressed so that a tearable bridge is defined between the third and fourth slits and so that a tearable bridge is defined between the fourth slit and the second edge of such outer segment. 4. The carrier stock of clause 1, wherein the series of frangible bridges include longitudinally staggered bridges. 5. The carrier stock of clause 1, wherein the series of frangible bridges are defined by slits including a slit in each tab and a slit in the outer segment formed with such tab. 6. The carrier stock of clause 5, wherein the last-mentioned slits are disposed approximately at a right angle to each other when the carrier stock is unstressed.

Claims: Carrier stock (10) for machine application to substantially identical containers (12), the stock being formed from a single sheet of resilient polymeric material and being severable to form individual carriers (20) with separate apertures (14) to receive the individual containers (12), the stock being formed for each individual carrier with integrally joined band segments defining the separate apertures (14), the segments including outer segments (22) extending in a generally longitudinal direction when the stock is unstressed, each outer segment being formed with a tab (30) which extends in a generally transverse direction from such outer segment (22) when the stock is unstressed, and which provides a tear open feature; characterised in that each tab (30) is slit to define a first slit (32), which extends in a generally longitudinal direction when the stock (10) is unstressed, and a second slit (40), which extends in a generally transverse direction when the stock (10) is unstressed. A carrier stock according to claim 1, wherein each tab (30) extends into one of the separate apertures (14) when the stock is unstressed. A carrier stock according to claim 1 or 2, wherein the second slit (40) is spaced from the first slit (32) to define a frangible bridge (42) between the first (32) and second (40) slits. A carrier stock according to any one of the preceding claims, wherein each tab (30) has an outer edge (36) and wherein the first slit (32) of each tab (30) has an open end (34) at the outer edge (36) of the tab (30). A carrier stock according to any of claims 1 to 3, wherein each tab (30) has an outer edge (36) and wherein the first slit (34) of each tab (30) has one end (34') spaced from the outer edge (36) of the tab (30) to define a frangible bridge (60') between said end (34') and the outer edge (36) of the tab (30). A carrier stock according to claim 5, wherein the first (32) and second (40) slits of each tab (30) are sections of a continuous slit (32''',62''',40'''). A carrier stock according to claim 6, wherein the continuous slit of each tab comprises a curved section (62''') connecting the first (32''') and second (40''') slits of the tab (30'''). A carrier stock according to any one of the preceding claims, wherein the first (32) and second (40) slits of each tab (30) are arranged so that an imaginary line extending in a generally longitudinal direction from the first slit (32) intersects the second slit (40) so that portions of the second slit (40) extends on each side of the imaginary line when the stock is unstressed. A carrier stock according to any one of the preceding claims, wherein each outer segment (22) is slit to define a third slit (50), which extends in a generally longitudinal direction when the stock is unstressed, so that a frangible bridge (54) is defined between the third slits (50) and the second slit (40) of the tab (30). A carrier stock according to any one of claims 1 to 8, wherein each outer segment (22) has a first edge (44) and a second edge (46), the first edge (44) merging with the outer edge (36) of the tab (30), and wherein each outer segment (22) is slit to define a third slit (50), which extends in a generally longitudinal direction when the stock is unstressed so that a frangible bridge (54) is defined between the third slit (50) and the second slit (40) and to define a fourth slit (52), which extends in a generally longitudinal direction when the stock is unstressed, so that a frangible bridge (56) is defined between the third (50) and fourth (52) slit and so that a frangible bridge (58) is defined between the fourth slit (52) and the second edge (46) of the outer segment (22).

Inventors: MARCO LESLIE S, MARCO, LESLIE S.
Applicants: ILLINOIS TOOL WORKS, ILLINOIS TOOL WORKS INC.
Application year: 1991
Main classification: B65D71
IPC codes: B65D67, B65D71, B65B11