Abstract:
In one aspect, the present invention is directed to a sheet comprising: a first section on one side of the sheet; and a second section on the other side of the sheet and parallel to the first section; wherein the distance between the tip of the first section and the tip of the second section being substantially greater than zero, thereby upon applying a force along the tips, detaching the sheet between the tips. In another aspect, the present invention is directed to a sheet comprising: a section on one side of the sheet in which the shortest distance between the tip of the section and the un-sectioned edge of the sheet is substantially greater than zero, thereby upon applying a force along the section, detaching the sheet between the tip and the edge.

Description:
[0001]    The present application claims priority from PCT/IL 2006/001274 application (publication number WO/2007/0578820) filed 2 Nov. 2006, claiming priority from U.S. Provisional Patent Application No. 60/736,333, filed Nov. 15, 2005, entitled “Means and methods for preventing visible perforation marks when detaching sheets from a notepad”, whose disclosures are incorporated by reference. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention generally relates to the field of press. More particularly, the invention relates to a detachable sheet which has reduced observable detachment marks, and a method and system for rendering such a detachable sheet. 
       BACKGROUND OF THE INVENTION 
       [0003]      FIG. 1  schematically illustrates a notepad, according to the prior art. Notepad  10  comprises a plurality of sheets  20 . Sheets  20  are banded by binding means. In  FIG. 1 , the binding means are clamps  40 , but other binding means can also be used, such as gluing. 
         [0004]    The sheet  20  comprises a perforation line  30 , for enabling tearing sheet  20  from notepad  10  over perforation line  30 . Thus, perforation line  30  is aimed to provide two functions: to allow tearing the sheet more easily in comparison to a non-perforated sheet and thus enforcing the tearing line to be substantially at the perforation line. 
         [0005]      FIG. 2  schematically illustrates an un-torn perforation line  30  of a sheet  20 , according to the prior art. The perforation line  30  is comprised of sectioned regions  32  and non-sectioned regions  34 . The non-sectioned regions  34  are “short” in order to enable “easy” tearing by a user. The shorter the non-torn region, the easier its tearing. The optimal length of the non-sectioned regions  34  (and the sectioned regions  32  as well) can be determined by experiment. It usually depends on the characteristics of the sheet, such as its thickness, the type of its fibers, and so forth. 
         [0006]      FIG. 3  schematically illustrates sheet  20  of  FIG. 2  after having been torn, according to the prior art. Tearing sheet  20  separates it into two parts:  20   a , and  20   b . As illustrated in  FIG. 3 , the torn perforation lines  30   a  and  30   b  are not uniform; thus, when tearing sheet  20  at perforation line  30 , separated rims  30   a  and  30   b  are neither straight nor “homogeneous”. 
         [0007]    Due to the non-esthetic nature of a sheet torn at a perforation line, a plurality of press products cannot be distributed as a notepad. For example, a business card necessarily must be esthetic as possible, and therefore business cards in the prior art are not distributed in a notepad form, but as separate entities which usually reside in a casing, generally a box. 
         [0008]    Another implementation which cannot be embodied as a perforated sheet is a postcard featuring a landscape. Generally, landscape postcards are distributed as single entities, or in connection with a plurality of postcards. 
         [0009]    Therefore, there is a long existing need for a sheet having greatly reduced, near unobservable detachment marks. 
         [0010]    Other objects and advantages of the invention will become apparent as the description proceeds. 
       SUMMARY OF THE INVENTION 
       [0011]    In one aspect, the present invention is directed to a sheet comprising: a first section on one side of the sheet; and a second section on the other side of the sheet and parallel to the first section; wherein the distance between the tip of the first section and the tip of the second section being substantially greater than zero, thereby upon applying a force along the tips, detaching the sheet between the tips. 
         [0012]    In one embodiment of the invention, the first section and the second section are rendered along the entire length of the sheet. 
         [0013]    Preferably, the sheet is banded in a notepad. 
         [0014]    The sheet may be of a business card, a postcard, a greeting card, a landscape card, and so forth. 
         [0015]    In another aspect the present invention is directed to a method for rendering a sheet detachable, the method comprising the steps of: rendering a first section on one side of the sheet; and rendering a second section on the other side of the sheet parallel to the first section; wherein the distance between the tip of the first section and the tip of the second section is substantially greater than zero, thereby applying a force along the tips resulting with detaching the sheet between the tips. 
         [0016]    In yet another aspect, the present invention is directed to an apparatus for rendering a sheet detachable, the apparatus comprising: a sectioning mechanism, for rendering a first section on one side of the sheet and optionally rendering a second section on the other side of the sheet and parallel to the first section; thereby upon applying a force along the tips, detaching the sheet. 
         [0017]    In one embodiment of the invention, the sectioning mechanism comprises at least one blade, for rendering the sections. 
         [0018]    The sectioning mechanism may comprise a supporting mechanism, for supporting the sheet, and/or a moving mechanism, for changing the position of the at least one blade with reference to the supporting mechanism, for rendering the sections. 
         [0019]    Changing the position of the at least one blade with reference to the supporting mechanism may be carried out: by moving the at least one blade toward the sheet; by moving the at least one blade along the sheet; by moving the sheet toward the at least one blade; by moving the sheet along the at least one blade, and so on. 
         [0020]    In yet another aspect, the present invention is directed to a sheet comprising: a section on one side of the sheet in which the shortest distance between the tip of the section and the un-sectioned edge of the sheet being substantially greater than zero, thereby upon applying a force along the section, detaching the sheet between the tip and the edge. 
         [0021]    In yet another aspect, the present invention is directed to a method for rendering a sheet detachable, the method comprising the steps of: rendering a section on one side of the sheet, wherein the shortest distance between the tip of the section and the un-sectioned edge of the sheet being substantially greater than zero, thereby upon applying a force along the section, detaching the sheet between the tip and the edge. 
         [0022]    In yet another aspect, the present invention is directed to a system for distributing a notepad having content such as business card and landscape postcard, the system comprising: a server accessible over the Internet, for accepting an order from a client to produce the notepad; a press machine, for printing the content on the sheets of the notepad; and a sectioning apparatus, for rendering a sheet detachable. The apparatus may comprise: a sectioning mechanism, for rendering a first section on one side of the sheet and optionally a second section on the other side of the sheet. 
         [0023]    The system may further comprise a software application, for designing the content. The software application may be adapted to operate as a web page, to operate as a stand-alone program, and so forth. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0024]    Exemplary embodiments are illustrated in the referenced figures. It is intended that the embodiments and figures disclosed herein be considered illustrative, rather than restrictive. The disclosure, however, both as to organization and method of operation, together with objects, features, and advantages thereof, may best be understood by reference to the following detailed description when read with the accompanying figures, in which: 
           [0025]      FIG. 1  schematically illustrates a notepad, according to the prior art. 
           [0026]      FIG. 2  schematically illustrates an un-torn perforation line  30  of a sheet  20 , according to the prior art. 
           [0027]      FIG. 3  schematically illustrates sheet  20  of  FIG. 2  after having been torn, according to the prior art. 
           [0028]      FIGS. 4   a  and  4   b  schematically illustrate the way a perforation line is executed, according to the prior art. 
           [0029]      FIGS. 5   a ,  5   b  and  5   c  schematically illustrate the way section lines are executed, according to a preferred embodiment of the invention. 
           [0030]      FIG. 6  is a three-dimensional view of a sheet  20 , which illustrates some terms used herein. 
           [0031]      FIG. 7   a  is a sectional view of cross-section A-A of  FIG. 6 , according to a preferred embodiment of the invention.  FIG. 7   b  is a sectional side-view of sheet  20  of  FIG. 7   a , after being torn.  FIG. 7   c  is a top view of the torn sheet  20  of  FIG. 7   b.    
           [0032]      FIG. 8   a  is a three-dimensional view of part  20   b  which has been detached from part  20   a , according to a preferred embodiment of the invention.  FIG. 8   b  is a three-dimensional view of the detached part  20   b  which has been turned upside-down, according to a preferred embodiment of the invention. 
           [0033]    Each of  FIGS. 9   a  to  9   e  schematically illustrate a cross-section (such as cross-section A-A of  FIG. 6 ), according to embodiments of the invention. 
           [0034]      FIG. 10  schematically illustrates an apparatus for rendering a sheet detachable, according to a preferred embodiment of the present invention. 
           [0035]      FIG. 11  schematically illustrates an apparatus for rendering a sheet detachable, according to another preferred embodiment of the present invention. 
           [0036]      FIG. 12  schematically illustrates a system for distributing a notepad of business cards, according to one embodiment of the invention. 
       
    
    
       [0037]    It will be appreciated that for simplicity and clarity of illustration, elements shown in the figures have not necessarily been drawn to scale. For example, the dimensions of some of the elements may be exaggerated relative to other elements for greater clarity. Further, where considered appropriate, reference numerals may be repeated among the figures to indicate corresponding or analogous elements. 
       DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
       [0038]    In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of the disclosure. However, it will be understood by those skilled in the art that the present disclosure may be practiced without these specific details. In other instances, well-known methods, procedures, components and circuits have not been described in detail so as not to obscure the present disclosure. 
       Generating a Perforation Line According to the Prior Art 
       [0039]      FIGS. 4   a  and  4   b  schematically illustrate the way a perforation line, such as line  30  of  FIG. 2 , is executed, according to the prior art.  FIG. 4   a  is a cross-section along the perforation line, and  FIG. 4   b  is a side cross-section thereof.  FIG. 4   a  is section A-A of  FIG. 4   b.    
         [0040]    The perforation line is executed by piercing sheet  20  with a group of blades  50 . The result is a perforation line, such as line  30  of  FIG. 2 . 
         [0041]    Each blade  50  of  FIG. 4   a  corresponds to an executed section, such as section  32  of  FIG. 2 . A distance  54  separates two adjacent blades  50 , resulting in non-sectioned regions, such as non-sectioned regions  34  of  FIG. 2 . 
       Performing Section Lines, According to a Preferred Embodiment of the Invention 
       [0042]      FIGS. 5   a ,  5   b  and  5   c  schematically illustrate the way section lines are executed, according to a preferred embodiment of the invention.  FIG. 5   a  is section A-A of  FIG. 5   b .  FIG. 5   c  is a three-dimensional view thereof. 
         [0043]    As can be seen in  FIG. 5   a , there are two blades  50   a  and  50   b , for executing two opposite sections along sheet  20 : a first blade  50   a  for executing a section on one side of the sheet  20 , and a second blade  50   b , for executing a section on the other side of the sheet  20 . The sectioning need not necessarily be carried out simultaneously. According to one embodiment of the invention, a section is carried out at one side of the sheet  20 , and afterwards the sheet  20  is turned upside-down, and a section is carried out on the other side of the sheet  20 . 
         [0044]      FIG. 6  is a three-dimensional view of a sheet  20 , which illustrates some terms used herein. The thickness of sheet  20  is marked as  80 . The length of the sheet  20  is marked as  84 , and the width of sheet  20  is marked as  82 . Marker  62  denotes the section performed by blade  50   a  (of  FIG. 5   c ). The “width”  82  of sheet  20  refers to the dimension of sheet  20  which is substantially parallel to the section line  62 . 
         [0045]      FIG. 7   a  is a sectional view of cross-section A-A of  FIG. 6 , according to a preferred embodiment of the invention.  FIG. 7   b  is a sectional side-view of sheet  20  of  FIG. 7   a , after being torn.  FIG. 7   c  is a top view of the torn sheet  20  of  FIG. 7   b.    
         [0046]    Sheet  20  is sectioned by  62  and  64 . Marker  66  denotes the “region” between tip  63  of section  62  and tip  65  of section  64 . In other words, when it applies to a cross-section, marker  66  denotes an imaginary line between tips  33  and  35 . 
         [0047]    Upon applying a force along region  66 , sheet  20  separates into two parts  20   a  and  20   b  at region  66 , as illustrated in  FIGS. 7   b  and  7   c , especially if the distance between tips  63  and  65  is less than thickness  80  of sheet  20 . 
         [0048]    The applied force may be of a tearing nature (i.e., pulling parts  20   a  and  20   b  of the sheet  20  along line  66  in opposite directions), bending force, and so forth. 
         [0049]    The imaginary line between tips  63  and  65  is marked herein as  66 , and referred to as “separation region” (in a sectional view) or “separation line” (when it refers to the entire width of the sheet  20 ). 
         [0050]    Reference is made now to  FIGS. 7   a ,  7   b  and  7   c . Upon tearing sheet  20  along separation line  66 , sheet  20  separates into two parts,  20   a  and  20   b . The separation region of part  20   a  along section  62  is marked as  62   a , and its corresponding region of part  20   b  is marked as  62   b . The separation region of part  20   a  along section  64  is marked as  64   a , and its corresponding region of part  20   b  is marked as  64   b . The separation region of part  20   a  is denoted as  66   a . The separation region of part  20   b  is marked as  66   b.    
         [0051]    While edges  62   a ,  62   b ,  64   a  and  64   b  are a result of a section, regions  66   a  and  66   b  are the result of tearing, and therefore, while lines  62   a ,  62   b ,  64   a  and  64   b  have a “straight” and “homogeneous” outlook, the outlook of lines  66   a  and  66   b  is neither “straight” nor “homogeneous”. But, as illustrated in  FIG. 7   c , which is a top view of the torn sheet  20  of  FIG. 7   b , this defect is hidden in top-view. In other words, the torn region  66   b  is hidden. Although torn region  66   b  is visible, the meaningful part of sheet  20  is  20   b , which may be a business card, a landscape postcard, and so forth, is hidden. 
         [0052]      FIG. 8   a  is a three-dimensional view of part  20   b  which has been detached from part  20   a , according to a preferred embodiment of the invention.  FIG. 8   b  is a three-dimensional view of the detached part  20   b  which has been turned upside-down, according to a preferred embodiment of the invention. 
         [0053]    As illustrated, while the torn line  66   b  is seen in the upside-down view of  FIG. 8   b , in  FIG. 8   a  torn line  66   b  is hidden. The fact that the torn line is hidden from a top-view, all the edges of part  20   b  are therefore “straight” and “homogeneous”. 
         [0054]    According to one embodiment of the invention, the sections are substantially parallel, thus leaving substantially the same distance between the tips of the sections. However, it should be understood that the sections do not necessarily have to be parallel. 
       Sectioning Forms 
       [0055]    Each of  FIGS. 9   a  to  9   e  schematically illustrate a cross-section (such as cross-section A-A of  FIG. 6 ), according to embodiments of the invention. In these embodiments, the depth of sections  62  and  64  constitutes about a third of the thickness of the sheet  20 . However, this is only an example, and other proportions may be used, as well. 
         [0056]    In the embodiment of  FIG. 9   a  the planes of sections  62  and  64  are perpendicular to the plane of sheet  20 , and therefore they are parallel each to other. However, the planes of sections  62  and  64  are not on the same plane. The advantage of this embodiment is that separation line  66  of a torn sheet is hidden from view from one side of the sheet, although it may be seen from the other side of the sheet. 
         [0057]    In the embodiment of  FIG. 9   b , the planes of sections  62  and  64  are on the same plane. The drawback of this embodiment is that the separation line of a torn sheet is seen from both sides of the sheet. 
         [0058]    In the embodiment of  FIG. 9   c , the planes caused by sections  62  and  64  are not perpendicular to the plane of sheet  20 , but are on the same plane. The advantage of this embodiment is that the separation line of a torn sheet is hidden in view from one side of the sheet, although it is viewable from the other side of the sheet. Furthermore, since the sections are on the same plane but in opposite directions, both sections can be executed simultaneously. 
         [0059]    In the embodiment of  FIG. 9   d  the planes caused by sections  62  and  64  are not perpendicular to the plane of sheet  20 , and not parallel each to one another. The advantage of this embodiment is that the separation line of a torn sheet is hidden from view from both sides of part  20   b  of the sheet. 
         [0060]    The embodiment of  FIG. 9   e  may be applied to a sheet which the fibers of its external layers  22   a  and  22   b  are more condensed than the fibers of its internal layer  22   c . Such sheets are very common for business cards. 
         [0061]    In this embodiment only one section is required, in contrast to the two sections required in the embodiments of  FIGS. 9   a  to  9   d . The section is marked as  62 . The section  62  should not cut the entire layer  22   c , but rather leave at least a part of the external layer  22   b  un-sectioned. The un-sectioned part is marked as  66   b.    
         [0062]    A bending force along the section line  62  results with breaking the sheet (into parts  20   a  and  20   b  along its section line  62  at the region between tip  63  of the section  62  to the nearest point at the edge of sheet  63   b , i.e., line  66   b ). This is in contrast to the embodiments of  FIGS. 9   a  to  9   d  in which the sheet is torn. Nevertheless in this embodiment the breaking line is straight and “homogeneous”, due to the nature of the fibers which the external layers of the sheet are made of. 
         [0063]    As in the embodiments of  FIGS. 9   a  to  9   d , in the embodiment of  FIG. 9   e  the section may be perpendicular to the sheet plane, or in an angle with the sheet plane. 
         [0064]    A major advantage of this embodiment is that only one section is carried out in contrast to the embodiments of  FIGS. 9   a  to  9   d , and therefore the required work thereof diminishes. 
         [0065]    A desired distance  66  (i.e., the distance between the lines of the rims  63  and  65  of the sections) may be determined by experiments. According to experiments carried out by the applicant, the desired distance  66  depends on characteristics such as the thickness of the sheet, the fibers of the sheet, the direction of the sections, and so forth. 
         [0066]    Experiments carried out by the applicant of the present application for patent have indicated that in a paper sheet of XX gr. per squared meter, which is typical for business cards, sections of YY mm and a distance of ZZ mm between the tips of the sections produce easy tearing, with the tearing marks well hidden. 
         [0067]    In the case of landscape postcards, which use a XX gr. per squared meter paper, sections of YY mm and a distance of ZZ mm between the tips of the sections produce easy tearing with the marks well hidden. 
         [0068]      FIG. 10  schematically illustrates an apparatus for rendering a sheet detachable, according to a preferred embodiment of the present invention.  FIG. 11  schematically illustrates an apparatus for rendering a sheet detachable, according to another preferred embodiment of the present invention. 
         [0069]    The apparatus comprises:
       a supporting mechanism  92 , on which the sheet  20  is placed;   an approaching mechanism  90 , for approaching the blades  50  to the sheet (or alternatively approaching the sheet to the blades); and   a feeder (not illustrated), for placing the sheet on the support mechanism, and removing the sheet  20  from the supporting mechanism.       
 
         [0073]    In the embodiment of  FIG. 10 , the approaching mechanism  90  is based on rotational movement, while in the embodiment of  FIG. 11 , approaching mechanism  90  is based on linear movement. The movement lane is illustrated in  FIGS. 10 and 11  as a dashed arrow. 
         [0074]    As mentioned above, the approaching mechanism may approach the blades to the sheet, as illustrated on  FIGS. 10 and 11 , or approach the sheet to the blades (not illustrated). 
         [0075]    Those skilled in the art will appreciate that feeders are well known in the art of press, and for the sake of simplicity they have not been illustrated in the figures herein. 
         [0076]    In the embodiments of  FIGS. 10 and 11  the operation of “punching” a sheet must be carried out twice: once for rendering a section on one side of the sheet, and afterwards on the other side of the sheet. Thus, when using the same apparatus for punching both sides of a sheet, the sheet has to be fed twice, the first for punching one side, and the second for punching the second side. 
         [0077]    According to another embodiment of the invention, the sections of both sides of a sheet are carried simultaneously. A mechanism for rendering sections on both sides of a paper simultaneously, may be based on two approaching mechanisms, one for each side of the paper, and each having its own blades. Such a mechanism is not illustrated herein. 
         [0078]    A section may be carried out by “punching”, as illustrated in  FIGS. 10 and 11 , by cutting (not illustrated), and so forth. 
       A System for Distributing Detachable Business Cards 
       [0079]      FIG. 12  schematically illustrates a system for distributing a notepad of business cards, according to one embodiment of the invention. 
         [0080]    A user designs a business card using computer  100 . This can be carried out by a program thereof, by a web site, and so forth. The design is sent via the Internet  102  to a server  104  of the press firm. The press firm produces notepads of business cards which are detachable according to the present invention, using machinery  106 . The printed and detachable business cards are sent to the user via delivery means  108 , such as mail, messenger, etc. 
         [0081]    Business cards are only one example, and many other detachable press products may be distributed this way, such as landscape postcards, greeting postcards, and so forth. 
         [0082]    While certain features of the disclosure have been illustrated and described herein, many modifications, substitutions, changes, and equivalents may occur to those skilled in the art. Those skilled in the art will appreciate that the invention can be embodied in other forms and ways, without losing the scope of the invention. The embodiments described herein should be considered as illustrative and not restrictive.