DEVICE FOR BINDING SHEETS IN A PACK, AND BOUND BUNDLE
TECHNICAL FIELD
The present invention relates to a device for binding sheets in a pack, and to a bound bundle. BACKGROUND ART
As is known, packed sheets with holes along one edge of the pack are bound using substantially tubular binding devices comprising an elongated, substantially C-section spine portion, and a number of curved tongues formed integrally with the spine portion and spaced to form an elastic comblike structure. Each tongue is inserted inside a respective (preferably rectangular) hole in the pack and through the pack so that a respective end portion rests on an inner surface of the spine portion to firmly connect and bind the sheets into a bundle.
Known binding devices of the above type have a number of drawbacks, including the following: the elongated spine portion projects frontwards and laterally from the bundle, so that the bundle is often difficult to shelve or place alongside other bound bundles; binding devices of different sizes, in particular
with elongated spine portions of different shape and width, are required for binding bundles of different thickness; writing or printing is not normally possible on the spine of the bound bundle, by the spine being defined by the outer surface of 1 the spine portion, which is curved and made of plastic material; the binding device (being made of plastic material) must be detached from the packed sheets when disposing of, e.g. burning, the bundle.
DISCLOSURE OF INVENTION
It is an object of the present invention to provide a device for binding packed sheets, designed to eliminate the drawbacks of known devices. According to the present invention, there is provided a sheet binding device of the type described in Claim 1.
The present invention also relates to a bound bundle of the type described in Claim 14. BRIEF DESCRIPTION OF THE DRAWINGS
A non-limiting embodiment of the invention will be described by way of example with reference to the accompanying drawings, in which:
Figure 1 shows a view in perspective of a sheet binding device in accordance with the teaching of the present invention;
Figures 2a, 2b, 2c, 2d, 2e show side views of stages in the use of the sheet binding device according to the
present invention.
BEST MODE FOR CARRYING OUT THE INVENTION
Number 1 in Figure 1 indicates as a whole a sheet binding device comprising a rectangular strip element 2 having a number of flexible tongues 7 arranged combfashion along a first straight major-side edge 2a. Tongues 7 are preferably die-cut integrally with strip element 2.
Strip element 2 may be formed by die-cutting a sheet of cardboard, a sheet of plastic material or cloth, or a sheet of metal material (e.g. a flexible sheet of aluminium) .
Strip element 2 may, however, be made of various materials, providing' strip element 2 can be bent into different parts.
Tongues 7 are equally spaced with spacing P (Figure
1) along straight edge 2a, and are all of the same length
L; and each tongue 7 extends perpendicularly to straight edge 2a, and is rectangular with a rounded minor-side free end 7e.
Rectangular strip element 2 is also defined by a second straight major-side edge 2b, and by two straight minor-side edges 21.
Strip element 2 comprises a first application portion 10 extending along the whole length of straight edge 2a. First application portion 10 is substantially flat and in the form of an elongated rectangle of a width
APWl, measured perpendicularly to straight edge 2a,
smaller than the width W of rectangular strip element 2. First application portion 10 is covered with adhesive material 12, and has a removable strip 13 for protecting adhesive material 12. Strip element 2 also comprises a second application portion 17 extending along the whole length of second straight edge 2b; second application portion 17 is substantially flat and in the form of an elongated rectangle of a width APW2 , measured perpendicularly to straight edge 2b, smaller than the width W of flat strip element 2 and greater than width APW1.
Second application portion 17 is also covered with adhesive material 18, and has a removable strip 19 protecting adhesive material 18. First and second application portions 10 and 17 are separated and spaced laterally by a rectangular intermediate portion 20 of strip element 2 having no adhesive material, and are located on the same face of strip element 2. Intermediate portion 20 has two preferential bend lines 21 (Figure 1) which extend, along the whole length of intermediate portion 20, parallel to straight major edges 2a and 2b and therefore along a portion of strip element 2 having no adhesive. To use the device according to the present invention, a pack 30 (Figure 2a) is prepared of rectangular sheets 31 having a series of rectangular- section holes 33 extending along a straight major-side
edge 34 of each sheet 31.
Pack 30 is defined, on opposite faces, by a first and second end sheet 31a, 31b preferably made of semirigid material (e.g. cardboard or a sheet of plastic material) .
According to the present invention, each tongue 7 is inserted through a respective hole 33 in pack 30 so that each end 7e projects from hole 33 (Figure 2b) . This may be done manually (Figures 2a and 2b) by positioning pack 30 horizontally and strip element 2 vertically with tongues 7 facing holes 33, and then inserting tongues 7 inside respective holes 33 (figure 2b) .
Tongues 7 slide through holes 33 until first edge 2a comes to rest on first end sheet 31a (Figure 2b) ; in which position, each end 7e projects from hole 33 and beyond end sheet 31b.
At this point, the strip element is bent roughly 90° into an L (arrow PI in Figure 2b) so that first application portion 10, from which protective strip 13 has been removed beforehand, rests on (Figure 2c) and sticks to a peripheral edge portion of pack 30 defined by the portion 3lw of first sheet 31a extending between holes 33 and edge 34. The width of portion 31w is substantially equal to width APW1. Strip element 2 is then bent again roughly 90° into an L (arrow P2 in Figure 2c) so that intermediate portion 20 is positioned contacting a front face of pack 30 as shown in Figure 2d.
Strip element 2 is then bent again roughly 90° into an L (arrow P3 in Figure 2d) so that second application portion 17, from which protective strip 19 has been removed beforehand, rests on (Figure 2e) and sticks firmly to ends 7e of tongues 7 (which are also bent onto second end sheet 31b) and to second end sheet 31b to form a bound bundle comprising sheets 31 retained by strip element 2 bent in successive stages.
The advantages of the present invention will be clear from the foregoing description: bent strip element 2 does not project with respect to the thickness of the bundle, which, being substantially parallelepipedal with no projecting parts, is therefore easy to shelve or place alongside other bound bundles; since a portion of each tongue 7 need simply project from the pack of sheets, device 1 may be used for binding packs of sheets of different thicknesses; writing or printing may be applied to strip element 2, which, when bent and glued as described above, also defines the spine of the bound bundle at intermediate portion 20; and the binding device may be made of recyclable (e.g. paper) material to avoid the necessity of removing the device when disposing of, e.g. burning, the bundle.
Moreover, binding device 1 may be made by simply die-cutting and gluing readily available materials, and is therefore cheap to produce.
The binding device may also be used for security purposes, to prevent sheets from being replaced or added to the bundle, by, for example, initialling or sealing (not shown) the overlapping portion 7s of bent strip element 2 and second end sheet 31b (Figure 2e) . In the event the bundle is opened, glue 18 must be detached from second end sheet 31b, thus destroying or altering the initialling or seal.
Clearly, changes may be made to the sheet binding device as described and illustrated herein without, however, departing from the scope of the present invention.
Glue 12, 18 may even be thermoformable, in which case, protective sheets 13, 19 may be dispensed with.