Patent Publication Number: US-2007101848-A1

Title: Corner trimming device

Description:
BACKGROUND OF THE INVENTION  
      1. Field of the Invention  
      The present invention relates to a corner trimming device and, more particularly, to a corner trimming device for trimming corners of a sheet member, such as a sheet of paper.  
      2. Description of the Related Art  
      A corner trimming device is used to trim the corners of a sheet member, such as a sheet of paper, a name card, a photograph or the like. A conventional corner trimming device was disclosed in the U.S. Pat. No. 6,840,145B1 to Lee, filed on Jul. 8, 2003, entitled “DEVICE FOR TRIMMINING CORNER OR SHEET MEMBER”. In such a conventional corner trimming device, the blade is made of an elastic member so that the blade has an elastically restoring effect. However, the blade has a very small thickness to maintain the elasticity of the blade, thereby increasing difficulty in fabrication of the blade, and thereby increasing costs of fabrication. In addition, the blade is very thin, so that the blade is easily worn out or broken due to an excessive force. Further, the blade easily produces elastic fatigue during a long-term utilization, thereby affecting operation of the corner trimming device.  
     SUMMARY OF THE INVENTION  
      In accordance with the present invention, there is provided a corner trimming device, comprising a base, a placement seat secured on the base, an anvil secured on the placement seat, a pivot seat pivotally mounted between the base and the placement seat, a trimming blade secured in the pivot seat to move therewith and movable relative to the anvil, and a restoring spring mounted between the base and the pivot seat to provide a restoring force to the pivot seat.  
      The primary objective of the present invention is to provide a corner trimming device having an automatically restored function.  
      Another objective of the present invention is to provide a corner trimming device, wherein the restoring spring and the elastic plate provide a restoring force to the pivot seat to restore the press portion and the trimming blade to the original state, thereby facilitating a user operating the press portion to trim the corner of the paper.  
      A further objective of the present invention is to provide a corner trimming device, wherein the restoring spring and the elastic plate provide a buffering effect to movement of the pivot seat, so that the trimming blade is moved slowly and stably so as to trim the corner of the paper smoothly.  
      A further objective of the present invention is to provide a corner trimming device, wherein the elastic plate is limited by the two limit plates of the base so as to limit the movement of the pivot seat, so that of the pivot seat and the trimming blade are moved uniformly without being inclined reclined sideward so as to trim the corner of the paper exactly.  
      Further benefits and advantages of the present invention will become apparent after a careful reading of the detailed description with appropriate reference to the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       FIG. 1  is a perspective view of a corner trimming device in accordance with the preferred embodiment of the present invention.  
       FIG. 2  is an exploded perspective view of the corner trimming device as shown in  FIG. 1 .  
       FIG. 3  is a plan cross-sectional view of the corner trimming device as shown in  FIG. 1 .  
       FIG. 4  is a schematic operational view of the corner trimming device as shown in  FIG. 3 . 
    
    
     DETAILED DESCRIPTION OF THE INVENTION  
      Referring to the drawings and initially to  FIGS. 1-3 , a corner trimming device in accordance with the preferred embodiment of the present invention comprises a base  11 , a placement seat  13  secured on the base  11 , an anvil  25  secured on the placement seat  13 , a pivot seat  12  pivotally mounted between the base  11  and the placement seat  13 , a trimming blade  19  secured in the pivot seat  12  to move therewith and movable relative to the anvil  25 , and a restoring spring  18  mounted between the base  11  and the pivot seat  12  to provide a restoring force to the pivot seat  12 . The trimming blade  19  is located at a height greater than that of the anvil  25  by the elastic force of the restoring spring  18 .  
      The base  11  is substantially triangular. The base  11  is provided with a receiving portion  20  located under the anvil  25  and the trimming blade  19  to receive chips cut by the anvil  25  and the trimming blade  19 . A bottom cap  16  is removably mounted on a bottom of the receiving portion  20  of the base  11 . The base  11  is formed with a plurality of through holes  14 . The base  11  has an end portion provided with a fixing post  17  and a mediate portion provided with two limit plates  21 .  
      The placement seat  13  is secured on the base  11  by a plurality of locking bolts  15  which are extended through the through holes  14  of the base  11 . The placement seat  13  has a platform  24 . The placement seat  13  is substantially triangular and has two side walls  130  inclined relative to each other to form a substantially V-shaped profile. The platform  24  of the placement seat  13  is located between the two side walls  130 .  
      A bent elastic plate  27  is mounted on a bottom of the placement seat  13  and has a first end located above and rested on the two limit plates  21  of the base  11 . The first end of the elastic plate  27  is secured on the bottom of the placement seat  13  by a locking screw  28 .  
      The anvil  25  is secured on a corner of the platform  24  of the placement seat  13  by a locking screw  26  and has a periphery formed with a convex cutting edge  250 .  
      The pivot seat  12  has a first portion protruded outward from the placement seat  13  and provided with a press portion  22  that is movable relative to the base  11  and a second portion located between the base  11  and the placement seat  13  and provided with a resting bar  23  located above and rested on a second end of the elastic plate  27 . The resting bar  23  of the pivot seat  12  is rotatable relative to the placement seat  13  by pressing the press portion  22  to press the second end of the elastic plate  27 . The press portion  22  of the pivot seat  12  has an inside provided with a fixing post  220 , and the restoring spring  18  is mounted between the fixing post  17  of the base  11  and the fixing post  220  of the pivot seat  12 . The pivot seat  12  is substantially V-shaped and has two arms  120  inclined relative to each other, wherein first ends of the two arms  120  are connected to form the press portion  22 , and the resting bar  23  is mounted between second ends of the two arms  120 .  
      The two side walls  130  of the placement seat  13  encompass the two arms  120  of the pivot seat  12 , and the resting bar  23  of the pivot seat  12  is located under the platform  24  of the placement seat  13 .  
      The trimming blade  19  is secured in a mediate portion of the pivot seat  12  by a plurality of locking screws  29  and movable relative to the anvil  25  by pressing the press portion  22 . The trimming blade  19  is substantially arc-shaped and has a periphery formed with a concave cutting edge  190  that is movable to contact the convex cutting edge  250  of the anvil  25 .  
      In operation, referring to  FIGS. 3 and 4  with reference to  FIGS. 1 and 2 , when a sheet of paper (not shown) is placed on the platform  24  of the placement seat  13 , the corner of the paper is located between the trimming blade  19  and the anvil  25 . When the press portion  22  of the pivot seat  12  is pressed downward as shown in  FIG. 4 , the trimming blade  19  is movable downward relative to the anvil  25  so that the corner of the paper is cut by the concave cutting edge  190  of the trimming blade  19  and the convex cutting edge  250  of the anvil  25 . Thus, the corner of the paper is trimmed to have a smooth shape.  
      At this time, when the press portion  22  of the pivot seat  12  is pressed downward, the resting bar  23  of the pivot seat  12  presses the second end of the elastic plate  27  which provides a buffering effect to movement of the pivot seat  12 , so that the trimming blade  19  is moved smoothly and stably so as to trim the corner of the paper smoothly and exactly.  
      Accordingly, the restoring spring  18  and the elastic plate  27  provide a restoring force to the pivot seat  12  to restore the press portion  22  and the trimming blade  19  to the original state as shown in  FIG. 3 , thereby facilitating a user operating the press portion  22  to trim the corner of the paper. In addition, the restoring spring  18  and the elastic plate  27  provide a buffering effect to movement of the pivot seat  12 , so that the trimming blade  19  is moved slowly and stably so as to trim the corner of the paper smoothly. Further, the elastic plate  27  is limited by the two limit plates  21  of the base  11  so as to limit the movement of the pivot seat  12 , so that of the pivot seat  12  and the trimming blade  19  are moved uniformly without being inclined reclined sideward so as to trim the corner of the paper exactly.  
      Although the invention has been explained in relation to its preferred embodiment(s) as mentioned above, it is to be understood that many other possible modifications and variations can be made without departing from the scope of the present invention. It is, therefore, contemplated that the appended claim or claims will cover such modifications and variations that fall within the true scope of the invention.