The present invention relates to a stationary and, more particularly, to a folding structure for a plastic plural-sheet stationary.
Foldable folders, including but not limited to document folders, are widely used in the field of stationary. The description of an example document folder is set forth hereinafter. As shown in
In view of the problems of the prior art, an improved structure is required after understanding the cause of the above problems.
To solve the above problems, the present invention provides a plastic plural-sheet stationary comprising plural plastic sheets that are superimposed on one another. The plastic plural sheets includes at least two element sheets made of plastic. The outermost element sheet includes a folding edge. Two first fusion lines are provided to securely connect the plural plastic sheets formed by the superimposed element sheets through fusion. The two first fusion lines are located on two sides of the folding edge. A spacing between the two first fusion lines is greater than twice a superimposed thickness of the plural plastic sheets.
Firstly, since the plural sheets (such as first and second plastic sheets) in the present invention are made of plastic material which is elastic, the plural sheets can properly extend during folding, avoiding breakage. Furthermore, the first sheet includes a folding edge to permit easy folding of the plural sheets along the folding edge. Furthermore, two first fusion lines are provide to securely connect the first and second sheets through fusion, and the two first fusion lines are located on two sides of the folding line.
In the present invention, by providing the two first fusion lines to connect the plural sheets through fusion, when the plural sheets (such as the first and second sheets) are folded along the folding edge, the sheet at the inner side will generate a corrugation area due to the above-mentioned “inner side effect”. Nevertheless, the corrugation area spreading towards two sides will be stopped by the two first fusion lines providing an isolation effect. Thus, the corrugation area cannot spread further and are, thus, effectively restricted between the two first fusion lines. Therefore, if the spacing between the two first fusion lines can be reduced as much as possible, the corrugation area is accordingly minimized, such that the region of the plural sheets outside of the corrugation area can be maintained smooth after folding the plural sheets. Theoretically, the spacing between the two first fusion lines is the smaller the better (because the corrugation area is smaller). The spacing between the two first fusion lines must be limited to assure the functionality of two first fusion lines in stopping outward spread of the corrugation area. Specifically, the spacing between the two first fusion lines is twice the superimposed thickness of the plural sheets to effectively stop outward spread of the corrugation area.
Although the folding structure according to the present invention is not complicated, the folding structure can effectively overcome the drawbacks of the prior art. Thus, it is appreciated that the present invention is not easy to achieve nor obvious.
The present invention will become clearer in light of the following detailed description of illustrative embodiments of this invention described in connection with the drawings.
The present invention relates to a folding structure for a plastic plural-sheet stationary. Specifically, the present invention relates to a plastic plural-sheet stationary comprising plural plastic sheets that are superimposed on one another. The plastic plural sheets includes at least two element sheets made of plastic. The outermost element sheet includes a folding edge. Two first fusion lines are provided to securely connect the plural plastic sheets formed by the superimposed element sheets through fusion. The two first fusion lines are located on two sides of the folding edge. A spacing between the two first fusion lines is greater than twice a superimposed thickness of the plural plastic sheets. The present invention will be set forth by way of example embodiments.
With reference to
The term “folding edge” used herein refers to a pattern or trace formed by applying an external force before the manufacturing process, so as to provide convenience for subsequent processing or use.
In this embodiment, the first sheet 11 includes a folding edge 111 to permit easy folding of the plural sheets (such as the first and second sheets 11 and 12) along the folding edge 111. Furthermore, two first fusion lines 16 are provided to securely connect the plural sheets by fusion, and the two first fusion lines 16 are located on two sides of the folding edge 111.
According to the present invention, by the provision of the two first fusion lines 16 that securely connect the plural sheets together by fusion, when the plastic plural sheets (such as the first and second sheets 11 and 12) are folded along the folding line 111, the second sheet 12 at the inner side will be affected by the above-mentioned “inner side effect” and, thus, will inevitably generate a corrugation area A around the around the superimposed portion (particularly the folding portion). Nevertheless, when the corrugation area A spreads to the two first fusion lines 16, the two first fusion lines 16 stops the spread (providing an isolation effect), avoiding further outward spread of the corrugation area A. Thus, the corrugation area A will be restricted between the two first fusion lines 16. Theoretically, if the spacing between the two first fusion lines 16 is minimized, most region (the region outside of the corrugation area A) of the plural sheets after folding can be maintained smooth (not affected by the corrugation area A). This is because the spacing between the two first fusion lines 16 is minimized and, thus, minimize the corrugation area A, such that the surface smoothness of the plural sheets is scarcely affected.
Theoretically, the spacing between the two first fusion lines 16 is the smaller the better, because the corrugation area A is smaller. Nevertheless, the spacing between the two first fusion lines 16 must be limited when considering the structural change occurred during folding of the plural sheets. In an embodiment shown in
With reference to
Still referring to
The second sheet 12 further includes a fourth outer pocket layer 123 superimposed on the outer side thereof and located adjacent to the first pocket opening 13 of the first pocket. The fourth outer pocket layer 123 and the second sheet 12 define a fifth pocket including a fifth pocket opening 123A and a closed bottom 123B opposite to the fifth pocket opening 123A. The fifth pocket opening 123A and the third pocket opening 122A face each other. The two first fusion lines 16 extend through the third outer pocket layer 113 and the fourth outer pocket layer 123 to connect the third and fourth outer pocket layers 113 and 123 and the first and second sheets 11 and 12 together by fusion. The spacing between the two first fusion lines 16 is greater than twice a superimposed thickness of the first and second sheets 11 and 12 and the third and fourth outer pocket layers 113, 123.
The corrugation area of the third and fourth outer pocket layers 113 and 123 and the first and second sheets 11 and 12 fused together is diagrammatically shown in an example embodiment shown in
It is noted that when the plural sheets are folded, aside from the third outer pocket layer 113, the corrugation area A at any other sheet or any other two sheets can be stopped by the two first fusion lines 16 providing the isolation effect, thereby avoiding outward spread of the corrugation area A. Thus, the corrugation area A can be effectively restricted between the two first fusion lines 16, such that the region outside of the corrugation area A can be maintained smooth.
With reference to
The first sheet 11A further includes a fifth sheet 17A superimposed on an outer side thereof opposite to the second sheet 12A and identical to the second sheet 12A. The fifth sheet 17A and the first sheet 11A define a sixth pocket including a sixth pocket opening 171A facing a direction identical to that of the first pocket opening 13A. The sixth pocket further includes a closed bottom 172A opposite to the sixth pocket opening 171A. The two first fusion lines 16A extend through the fifth sheet 17A to securely connect the fifth sheet 17A and the first and second sheets 11A, 12A together by fusion.
With reference to
The first sheet 11A further includes a seventh sheet 19A superimposed on the outer side thereof opposite to the sixth sheet 18A. The seventh sheet 19A and the first sheet 11A define an eighth pocket including an eighth pocket opening 191A and a closed bottom 192A opposite to the eighth pocket opening 191A. The eighth pocket opening 191A and the sixth eighth pocket opening 171A face each other. Two second fusion lines 16B are provided to securely connect the sixth sheet 18A, the seventh sheet 19A, and the first sheet 11A together by fusion. The two second fusion lines 16B are located on two sides of the folding edge 111A.
The corrugation area of the first sheet 11A, the second sheet 12A, and the fifth sheet 17A (which are referred to as “plural sheets”) fused together is diagrammatically shown in an example embodiment shown in
It is noted that when the plural sheets are folded, aside from the second sheet 12A, the corrugation area A at any other sheet or any other two sheets can be stopped by the two first fusion lines 16 providing the isolation effect, thereby avoiding outward spread of the corrugation area A. Thus, the corrugation area A can be effectively restricted between the two first fusion lines 16, such that the region outside of the corrugation area A can be maintained smooth.
A non-restrictive example of the fusion lines 16C (including the first and second fusion lines) is shown in
Although specific embodiments have been illustrated and described, numerous modifications and variations are still possible without departing from the scope of the invention. The scope of the invention is limited by the accompanying claims.