CA1332830C - Tearable core for rolled material and its method of manufacture - Google Patents

Abstract

A tearable core is disclosed formed in the conventional manner of spiral wrapping elongated strips on a mandrel, with the strips being adhered together to form the core. The strips according to the teachings of the present invention include a series of perforations arranged along and forming a reduced tear strength path in the strips. The reduced tear strength path of the strips are arranged to overlie each other when wound on the mandrel when forming the core to form a predetermined tear line in the core. In the preferred form, the reduced tear strength paths of the strips are parallel to the side edges such that the tear line spirals between the ends of the core when the strips are spirally wound on the mandrel. In the preferred form, the path of perforations of the first strip is generally intermediate the side edges and the path of perforations of the second strip is adjacent a side edge.

Description

-1 Tearable Core for Rolled Material and Its Method of Manufacture BACKGROUND
The present invention relates generally to cores for a roll of material and its method of manufacture, particularly to easily removable cores, and specifically to easily tearable cores for rolls of toilet paper or tissue or the like and its method of manufacture.
Toilet paper holders come in a variety of forms. For 10 example, one type of conventional home holder includes a semicylindrical body which is recessed in the wall and a spring biased telescoping pin extending between sockets q~, 13~2830 1 formed in the sides of the semicylindrical body upon which the core of the toilet paper roll may be supported. Other holders include arms having bearing bosses formed thereon for receipt in the opposite extremities of the core of the toilet paper roll, with at least one arm being pivotally mounted to allow insertion of the toilet paper roll.
It can be appreciated that when the toilet paper has been utilized from the roll, the core upon which the toilet paper is rolled remains in the holder. It can 10 be further appreciated that the telescoping pin is generally inaccessible except through the ends of the core.
Difficulty may be encountered in telescoping the pin to allow removal of the core from the spent roll to allow replacement with a fresh roll, with this difficulty 15 increasing for persons having weak and/or swollen fingers such as the result of arthritis, rheumatism, M.S., and other medical conditions or conditions arising from age.
Further, in situations such as public washrooms where a large number of toilet paper rolls must be replaced, 20 considerable time may be expended in removing cores from spent rolls from the holders to allow replacement.
one method which has been pursued to allow ease of toilet paper replacement is the use of separable core structures. Thus, while the heavy cardboard commonly 25 utilized in the manufacture of cores for toilet paper were difficult to destroy to allow removal from the holder, such separable cores were intended to be easily separated or to even automatically fall apart after all of the toilet paper was utilized from the core. However, 30 such prior separable cores have not been extensively utilized due to their difficulty in manufacture and specifically did not lend themselves to manufacture on equipment presently utilized in the manufacture of cores for toilet paper.
Thus, a need has arisen for a core for rolled material such as toilet paper which may be easily removed from - 13328~0 -1 holders by tearing and which can be easily manufactured on existing equipment without requiring modification.
SUMMARY
The present invention solves this need and other problems in the field of rolled material manufacture by providing, in its most preferred form, a core for supporting a roll of strip material formed by wrapplng a core strip having a reduced tear strength path formed therein around a mandrel, with the reduced tear strength 10 path forming a tear line ln the core for belng easlly torn therealong.
It is thus an alm of the present invention to provide a novel tearable core for rolled material.
It is thus an aim of the present invention to 15 provide a novel method of manufacture of a tearable core for rolled material.
It is further an aim of the present invention to provide such a novel tearable core having a predetermined, reduced tear strength line.
It is further an aim of the present invention to provide such a novel tearable core utilizing existing production equipment without requlring modification.
It is further an aim of the present invention to provide such a novel tearable core allowing easy removal 25 from holders by tearing.
It is further an aim of the present invention to provide such a novel tearable core which may be easily and economically manufactured.
It is further an alm of the present lnvention to 30 provide such a novel tearable core formed from at least one strip having a reduced strength path formed therein prior to its wrapping on a mandrel.
It is further an aim of the present invention to provide such a novel tearable core formed from at least 35 one strip having a reduced strength path formed therein which does not materially affect its longitudlnal strength, 13~2830 1 with the path being formed prior to the wrapping of the strip on a mandrel.
It is further an aim of the present invention to provide such a novel tearable core having a spiral tear line extending from end to end.
These and further aims and advantages of the present invention will kecrre clearer in light of the following detailed description of an lllustrative embodiment of this invention described in connection with 10 the drawings.
DESCRIPTION OF THE DRAWINGS
The illustrative embodiment may best be described by reference to the accompanylng drawings where:
Figure 1 shows a perspective view of a roll of strip 15 material supported by a tearable core in turn supported by a holder according to the preferred teachings of the present invention, with portions being shown in phantom.
Figure 2 shows a perspective view of the holder including the tearable core of Figure 1 being torn 20 according to the teachings of the present invention.
Figure 3 shows a partial, plan view of the core strips for forming the tearable core of Figure 1.
Figure 4 shows a partial, plan view illustrating the method of forming the core of Figure 1.
All figures are drawn for ease of explanation of the basic teachings of the present invention only; the extensions of the Figures with respect to number, position, relationship, and dimensions of the parts to form the preferred embodiment will be explained or will 30 be within the skill of the art after the following teachings of the present invention have been read and understood. Further, the exact dimensions and dimensional proportions to conform to specific force, weight, strength, and similar requirements will likewise 35 be within the skill of the art after the following teachings of the present invention have been read and 133~830 1 understood.
Where used in the various flgures of the drawings, the same numerals designate the same or similar parts.
Furthermore, when the terms "side", "edge", "end", 5 "free", "first", "second", "radial", "axial", and similar terms are used herein, it should be understood that these terms have reference only to the structure shown in the drawings as it would appear to a person viewing the drawings and are utilized only to facilitate describing 10 the invention.
DESCRIPTION
An easily tearable core and its method of manufacture according to the preferred teachings of the present invention are shown in the drawings and generally 15 designated 10. Core 10 is generally cylindrical ln configuration and supports a roll 12 of strlp materlal such as toilet paper, tissue, or the like wound thereon.
Core 10 may be rotatably supported in a conventional holder 14 to allow dispensing of the rolled material 12 from core 20 10 as needed. Holder 14 is shown in the drawlngs including first and second cantilevered arms 16 extending from a support surface having a spring biased telescoping pin 18 extending between the free ends of arms 16. Speclfically, pins 18 are shown as including reduced portions 20 which 25 are axially slidably received in sockets formed in arms 16.
Core 10 is generally manufactured according to present practice and on existing machines. Specifically, at least two strips of cardboard 22 and 24 are spirally wound on a mandrel 26 having an outer diameter generally equal to the 30 intended inner diameter of core 10, with suitable provisions being made to adhere the strips 22 and 24 together. Particularly, strip 22 has an end 28 removably secured to mandrel 26 and first and second parallel side edges 30 and 32 which are positioned to extend at an angle 35 with respect to mandrel 26. Thus, when mandrel 26 iS
rotated, strip 22 will wrap in a spiral on mandrel 26.

1 where it is desired to have core 10 formed of two cardboard thicknesses, edges 30 and edge 32 may generally abut with each other in a wrappèd condition on mandrel 26 and with edge 32 slightly overlapping edge 30 in the most preferred form. In its preferred form, strip 22 ls placed on mandrel 26 ln a dry form.
Strip 24 has the same width as strip 22 and includes first and second parallel side edges 34 and 36 which are positioned to extend at the same angle wlth respect to 10 mandrel 26 as strip 22 such that edges 34 and 36 are parallel to edges 30 and 32. In its preferred form, strip 24 is coated to adhere to strip 22. Where it is desired to have core 10 formed of two cardboard thlcknesses, end 38 of strip 24 is adhered to strip 22 wrapped on mandrel 15 26 such that strip 24 straddles the abutting edges 30 and 32 of spiraled strip 22 or in other words edges 34 and 36 of strip 24 are on opposite sides of and equidlstant abutting edges 30 and 32. It can further be appreciated that edges 34 and 36 may generally abut with each other in 20 a spiral wrapped condltlon on strlp 22 and mandrel 26 and with edge 36 slightly overlapping edge 34 in the most preferred form.
It can then be appreciated that strips 22 and 24 wrapped on mandrel 26 have a length considerably longer 25 than and a multiple of the lengths of core 10. Materlal having a length generally equal to that of wrapped strips 22 and 24 may then be rolled upon the wrapped strlps 22 and 24 to the desired diameter. Thereafter, this stock roll can be cut 40 radially to the desired lengths of core 30 10 and roll 12 and removed from mandrel 16 for suitable packaging for consumption and sale.
According to the teachings of the present invention, perforations 42 and 44 are formed in strips 22 and 24 prior to their spiral wrapping upon mandrel 26. As a 35 result, when strips 22 and 24 are wrapped upon mandrel 26 to eventually form core 10 according to standard 13~2830 1 manufacture ~ractice, perforations 42 and 44 form a tear line 46 along a prearranged route between the opposlte ends of core 10. Specifically,`ln its most preferred form, perforations 42 are provlded generally parallel to and closely ad~acent edge 30 of strip 22, with the perforations 42 being located a distance from edge 30 slightly greater than the overlap dlstance of edge 32 on edge 30 in the wrapped condition on mandrel 26.
Perforations 44 are provided generally parallel to and 10 intermediate edges 34 and 36 of strip 24 and specifically are slightly offset from the center to overlie the path of perforations 42 when strip 24 overlies and straddles strip 22 forming core 10. It can then be appreciated that perforations 42 and 44 lie along a spiral path along 15 mandrel 26 in the most preferred form of the present invention. Perforations 42 and 44 remove material from the cardboard forming strips 22 and 24 without a reduction in its thickness intermediate perforations 42 and 44 to form tear line 46 which allows tearing of core 10 at a 20 force considerably less than re~uired to tear the double cardboard thicknesses of strips 22 and 24 forming core 10 without perforations 42 and 44.
It can then be appreciated that after roll 12 as shown in phantom in Figure 1 has been consumed, core 10 remains 25 in holder 14 as shown in Flgure 2. To allow a new roll 12 to be placed in holder 14, it is only necessary to grab either end of core 10 next to tear line 46 and tear core 10 along tear line 46 which provides a predetermined, reduced tear strength path between the ends of core 10.
30 After core 10 has been torn along tear line 46 from end to end, core 10 may be easily slipped off telescoping pin 18 thus exposing the entire length of pin 18. At that time, pin 18 may be easily removed from between arms 16.
Specifically, problems of inaccessability to pin 18 as 35 were encountered for conventional cores especially by the elderly and handicapped are eliminated as pin 18 is 1-3328~0 1 completely exposed and easily accessible.
It can further be appreciated that core 10 according to the teachings of the present invention may be manufactured on conventional equipment without modification. Specifically, tear line 46 is not formed on the equipment forming core 10, and particularly tear line 46 is preformed in strips 22 and 24 in the most preferred form by perforations 42 and 44. It can further be appreciated that performations 42 and 44 can be easily 10 formed by conventional equipment utilized in producing strips 22 and 24.
It is believed that the spiraling nature of tear line 46 on core 10 is advantageous according to the preferred form of the teachings of the present invention over a tear 15 line extending axially straight on core 10. Specifically, perforations 42 and 44 are arranged longitudinally on strips 22 and 24 in the most preferred form to not materially affect the longitudinal strength of strips 22 and 24 reducing the likelihood of tearlng during wrapping 20 on mandrel 26. Since in the most preferred form strips 22 and 24 are spirally wrapped on mandrel 26, perforations 42 and 44 and thus tear line 46 formed thereby also spiral on mandrel 26 and thus core 10.
Now that the basic teachings of the present invention 25 have been explained, many extenslons and variations will be obvious to one having ordinary skill in the art. For example, although perforations 42 have been provided in strip 22 to compensate for overlapping of strip 22 in forming core 10, it can be appreciated that the reduced 30 strength of the ~oint between edges 30 and 32 may be relied upon especially where no or limited overlap is provided in combination with perforations 44 to form tear line 46 according to the teachings of the present invention.
Likewise, although strip 24 is shown and described as being wrapped upon strip 22, it can be appreciated that 133283~

1 this relationship may be reve~sed according to the teachings of the present invention. Similarly, more or less than two strips 22 and 24 may be provided according to the teachlngs of the present invention.
Additionally, although in the most preferred form perforations 42 and 44 are provided to create a reduced tear strength in the cardboard forming strips 22 and 24 and is believed to be advantageous at least because their ease of production, tear line 46 may take other forms 10 according to the teachings of the present invention.
Similarly, although only one form of holder 14 of a conventional construction is shown in the drawings, it can be appreciated that core 10 according to the teachings of the present invention may be equally applicable to other 15 forms of holders 14 including those set forth herein.
Furthermore, although in the most preferred form, tear line 46 is shown and described as being a spiral generally parallel to the spiral of edges 30, 32, 34, and 36 of strips 22 and 24 in core 10, it can be appreciated that 20 tear line 46 may have other path configurations as determined by the configuration of perforations 42 and 44 in strips 22 and 24 according to the teachings of the present invention.

Claims (16)

1. In a core for supporting a roll of strip material wound thereon, with the core formed by at least a first strip having first and second parallel side edges, with the first strip being spirally wound with the first side edge generally abutting with the second side edge, with the improvement comprising a tear line formed on the core comprising, in combination: means formed in the first strip forming the core for providing a reduced tear strength path in the first strip allowing the core to be easily torn along the path after the roll of strip material has been consumed from the core, with the reduced tear strength path being generally parallel to the first and second side edges of the first strip.

2. The core of claim 1 wherein the reduced tear strength path providing means comprises means formed in the strip for providing a reduced tear strength having portions of constant thickness as the remaining portions of the strip.

3. The core of claim 2 wherein the reduced tear strength path providing means comprises means for removing material from the strip along the reduced tear strength path in the strip.

4. The core of claim 3 wherein the reduced tear strength path providing means comprises perforations extending through the strip, with the perforations arranged along the reduced tear strength path.

5. The core of claim 4 wherein the core is formed by a second strip including first and second parallel side edges, with the second strip being spirally wound with the first side edge generally abutting with the second side edge, with the first strip being spirally wrapped on the second strip to straddle the first and second abutting side edges of the second strip, with the reduced tear strength path providing means of the first strip generally overlying the abutting side edges of the second strip.

6. The core of claim 5 wherein the side edges of the first strip are generally parallel to and equidistant the abutting side edges of the second strip, with the reduced tear strength path providing means being located generally intermediate and parallel to the first and second side edges of the first strip.

7. The core of claim 5 wherein the first side edge of the second strip overlaps the second side edge of the second strip when spirally wound by an overlap distance;
and wherein the core further comprises means formed in the second strip forming the core for providing a reduced tear strength path in the second strip generally parallel to the first side edge and spaced slightly more than the overlap distance from the first side edge, with the reduced strength path of the first strip overlying the reduced strength path of the second strip in the core.

8. The core of claim 1 wherein the core is formed by a second strip, with the tear line further comprising, in combination: means formed in the second strip for providing a reduced tear strength path in the second strip, with the first strip overlying the second strip and with the reduced tear strength path of the first strip overlying the reduced tear strength path of the second strip.

9. Method of manufacturing a roll of strip material comprising the steps of: providing at least a first core strip having first and second parallel side edges and having a reduced tear strength path formed therein; forming a core from the first core strip by spirally wrapping the first core strip on a mandrel with the first side edge generally abutting with the second side edge; rolling a length of strip material around the core; and simultaneously radially cutting the rolled strip material and the core at desired axial lengths for consumption and sale, with the reduced tear strength path extending between the opposite axial ends of the core generally parallel to the first and second side edges and allowing the core to be easily torn along the path after the roll of strip material has been consumed from the core.

10. The method of claim 9 wherein the step of providing a first core strip comprises the step of providing the first core strip having the reduced tear strength path with portions having a constant thickness as the first core strip.

11. The method of claim 10 wherein the step of providing a first core strip comprises the step of providing the first core strip having removed material from the first core strip along the reduced tear strength path.

12. The method of claim 11 wherein the step of providing a first core strip comprises the step of providing the first core strip having perforations along the reduced tear strength path.

13. The method of claim 12 further comprising the step of: providing a second core strip having first and second parallel side edges; and wherein the step of forming the core comprises the step of forming the core by spirally wrapping the second core strip on the mandrel with the first side edge of the second core strip generally abutting with the second side edge of the second core strip and by spirally wrapping the first core strip on the mandrel overlying the second core strip with the reduced tear strength path generally overlying the abutting first and second side edges of the spirally wound second core strip.

14. The method of claim 13 wherein the step of providing a first core strip comprises the step of providing the first core strip having the reduced tear strength path formed generally intermediate the first and second side edges of the first strip.

15. The method of claim 14 wherein the step of forming the core comprises the step of forming the core by spiral wrapping the second core strip on the mandrel with the first side edge of the second core strip generally abutting with the second side edge of the second core strip and by spirally wrapping the first core strip on the mandrel overlying the second core strip.

16. The method of claim 9 further comprising the step of providing a second core strip having a reduced tear strength path formed therein; and wherein the step of forming the core comprises the step of forming the core by wrapping the second core strip on the mandrel and wrapping the first core strip on the mandrel overlying the second core strip with the reduced tear strength path of the first core strip generally overlying the reduced tear strength path of the second core strip.