Abstract:
A paper corner protector cutter includes a base. The base is provided with a frame. The frame is pivotally connected with an operation rod. The operation rod is able to link a blade holder. The blade holder is provided with two blades. Two stop plates are disposed at two sides of the frame, enabling the blade holder to be located between the stop plates. Two stop plates are provided between the stop plates corresponding to the blade holder. The paper corner protector cutter can be assembled and positioned with ease by using a plate-type structure. The required time to assemble or disassemble the paper corner protector cutter can be decreased greatly to enhance the economic benefits.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The present invention relates to a packing material cutting machine, and more particularly to a paper corner protector cutter. 
         [0003]    2. Description of the Prior Art 
         [0004]    A conventional paper corner protector cutter comprises a base. The base is provided with two circular rods. A blade holder is provided between the two circular rods for insertion of a blade. The blade holder is pivotally connected with an operation rod, such that the operation rod can bring the blade holder to slide between the circular rods and the blade is used for cutting. 
         [0005]    For the blade holder to slide smoothly between the circular rods, the paper corner protector cutter needs a strict requirement for accuracy. When the paper corner protector cutter is assembled or the blade is replaced, it is necessary to adjust the position again and again for the blade holder to slide smoothly between the circular rods. Therefore, it consumes much time and for assembly of the paper corner protector cutter and replacement of the blade to increase the cost. Accordingly, the inventor of the present invention has devoted himself based on his many years of practical experiences to solve these problems. 
       SUMMARY OF THE INVENTION 
       [0006]    The primary object of the present invention is to provide a paper corner protector cutter. The paper corner protector cutter can be assembled and positioned with ease by using a plate-type structure. The required time to assemble or disassemble the paper corner protector cutter can be decreased greatly to enhance the economic benefits. 
         [0007]    In order to achieve the aforesaid object, the paper corner protector cutter of the present invention comprises a base, a frame, a handle, a blade holder, at least one blade, two stop plates, and at least one chopping board. The frame is disposed on the base. The frame comprises a first erect frame and a second erect frame which are spaced. The second erect frame is pivotally connected with an operation rod. The operation rod is pivotally connected with a drive shaft. The handle is pivotally connected to the first erect frame. The handle is pivotally provided with a connecting rod. The connecting rod is pivotally connected to the operation rod. The blade holder is disposed between the first erect frame and the second erect frame. The blade holder comprises a first plate and a second plate. A top end of each of the first plate and the second plate is formed with an opening. A drive block is provided in the openings of the first plate and the second plate. The drive block has a through hole. The drive shaft is inserted through the through hole of the drive block. The blade holder is connected with the drive block through the opening. The operation rod is pivotally connected with the drive block through the drive shaft. A bottom end of the first plate is formed with a first reverse V-shaped recess. A bottom end of the second plate is formed with a second reverse V-shaped recess. The blade holder has a blade room formed between the first reverse V-shaped recess and the second reverse V-shaped recess. The blade is inserted in the blade room. The two stop plates are disposed at two sides of the frame, enabling the blade holder to be located between the stop plates. The stop plates each have a first reverse V-shaped opening corresponding to the blade holder. The chopping board is fixedly connected to the stop plates. 
         [0008]    Through the plate-type structure of the frame, the blade holder, and the stop plate, the paper corner protector cutter of the present invention can be assembled and positioned with ease. The required time to assemble or disassemble the paper corner protector cutter can be decreased greatly to enhance the economic benefits. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0009]      FIG. 1  is a perspective view t of the present invention; 
           [0010]      FIG. 2  is an exploded view of the present invention; 
           [0011]      FIG. 3  is an exploded view of the blade holder of the present invention; 
           [0012]      FIG. 4  is a sectional view of the present invention; 
           [0013]      FIG. 5  is a partial enlarged sectional view of the present invention; 
           [0014]      FIG. 6  is a schematic view of the present invention, showing that the fixing pin is pulled out; 
           [0015]      FIG. 7  is a schematic view of the present invention when in use, showing that the blade holder is lifted; 
           [0016]      FIG. 8  is a schematic view of the present invention when in use, showing that the paper corner protector is inserted; 
           [0017]      FIG. 9  is a schematic view of the present invention when in use, showing that the paper corner protector is cut; 
           [0018]      FIG. 10  is a schematic view of the present invention when in use, showing that the handle is grasped by the user; 
           [0019]      FIG. 11  is another schematic view of the present invention when in use, showing that the handle is grasped by the user; 
           [0020]      FIG. 12  is a schematic view of the present invention when in use, showing that the blade holder is retained; and 
           [0021]      FIG. 13  is a schematic view of the present invention when in use, showing that the handle is retained. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0022]    Embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings. 
         [0023]      FIG. 1  is a perspective view t of the present invention.  FIG. 2  is an exploded view of the present invention.  FIG. 3  is an exploded view of the blade holder of the present invention.  FIG. 4  is a sectional view of the present invention. The present invention discloses a paper corner protector cutter. The paper corner protector cutter comprises a base  10 , a frame  20 , a handle  30 , a blade holder  40 , at least one blade  48 , two stop plates  50 , at least one chopping board  70 , and two covering plates  80 . 
         [0024]    The base  10  is a rectangular base and defines a long axis a and a short axis b. The base  10  is provided with a working insertion hole  11  in the direction of the short axis b for insertion of a fixing pin  90 . 
         [0025]    The frame  20  is erectly disposed on the base  10 . The frame  20  comprises a first erect frame  21  and a second erect frame  22  which are spaced and disposed along the long axis a. The second erect frame  22  is pivotally connected with an operation rod  23 . The operation rod  23  extends towards the first erect frame  21  to form a free end. The operation rod  23  is pivotally connected with a drive shaft  231  in the direction of the short axis b. 
         [0026]    The handle  30  comprises a pivot rod  301  which is pivotally connected to the first erect frame  21 . The handle  30  is pivotally connected with a connecting rod  31  located close to the pivot rod  301 . Another end of the connecting rod  31  is pivotally connected to the free end of the operation rod  23 . The handle  30  is further connected with a handle portion  32  through a fixing pin  33 . The handle portion  32  is bent upwards to form a bent portion  321 , such that the handle portion  32  has a J-shaped cross-section. 
         [0027]    The blade holder  40  is disposed between the first erect frame  21  and the second erect frame  22 . The blade holder  40  comprises a first plate  401  and a second plate  402 . A top end of each of the first plate  401  and the second plate  402  is formed with an opening  41 . A central portion of a bottom side of the opening  41  of each of the first plate  401  and the second plate  402  is provided with a flange  411 . A drive block  49  is provided in the openings  41  of the first plate  401  and the second plate  402 . The opening  41  and the drive block  49  each have a rectangular shape. The drive block  49  has a through hole  491 . The drive shaft  231  is inserted through the through hole  491  of the drive block  49 , such that the blade holder  40  is connected with the drive block  49  through the opening  41  and the operation rod  23  is pivotally connected with the drive block  49  through the drive shaft  231 . The opening  41  defines a first width w 1  in the direction of the long axis a. The drive block  49  defines a second width w 2  in the direction of the long axis a. The first width w 1  is greater than the second width w 2 . The drive block  49  is slightly against the bottom side of the opening  41  and the flange  411 , enabling the drive block  49  to slide within the opening  41  in the direction of the long axis a. In the present invention, a bottom end of the first plate  401  is formed with a first reverse V-shaped recess  421 , and a bottom end of the second plate  402  is formed with a second reverse V-shaped recess  422 . The first reverse V-shaped recess  421  is greater than the second reverse V-shaped recess  422 . When the first plate  401  and the second plate  402  are disposed side-by-side, a reverse V-shaped space  423  is formed. The blade holder  40  is provided with a reverse V-shaped board  403  in the reverse V-shaped space  423 . A blade room  43  is formed between the reverse V-shaped board  403  and the second plate  402 . Referring to  FIG. 5 , the second plate  402  is formed with a plurality of first locking holes  441 , second locking holes  451 , and steel ball accommodation rooms  453  along a circumferential portion of the second reverse V-shaped recess  422 . The second locking holes  451  are disposed close to the steel ball accommodation rooms  453 . The reverse V-shaped board  403  is formed with a plurality of third locking holes  4031  corresponding to the first locking holes  441 . First screw members  442  are inserted through the first locking holes  441  and the third locking holes  4031  to lock the second plate  402  and the reverse V-shaped board  403 . Each of the second locking holes  451  is screwedly provided with a tightening member  452 . In the present invention, the fastening member  452  comprises a second screw member  4521 . A disk-shaped elastic plate  4522  is fitted on the second screw member  4521 . When the second screw member  4521  is screwed, the disk-shaped elastic plate  4522  is pushed to lean against a steel ball  4523  in the steel ball accommodation room  453 , enabling the steel ball  4523  to have a prestressing force towards the blade room  43 . Outer sides of the first plate  401  and the second plate  402  are longitudinally provided with guide rails  46 . The first plate  401  and the second plate  402  are provided with a first positioning hole  471  and a second positioning hole  472 , respectively. Referring to  FIG. 7 , a first distance dl is defined from the first positioning hole  471  to the base  10 , and a second distance d 2  is defined from the second positioning hole  472  to the base  10 . The first distance d 1  is greater than the second distance d 2 . 
         [0028]    The blade  48  is inserted in the blade room  43 . The blade  48  is clamped between the steel ball  4523  of the tightening member  452  and the reverse V-shaped board  403 . In the present invention, two blades  48  are inserted along two sides of the reverse V-shaped board  403 . The blades  48  are existing cutter blades. 
         [0029]    The two stop plates  50  are disposed at two sides of the frame  20 , enabling the blade holder  40  to be located between the stop plates  50  and the guide rails  46  to be in contact with the stop plates  50 , which is beneficial for the blade holder  40  to slide between the stop plates  50 . The stop plates  50  each have a first reverse V-shaped opening  51  corresponding to the reverse V-shaped board  403  of the blade holder  40  and the blades  48 , enabling the reverse V-shaped board  403  of the blade holder  40  and the blades  48  to be exposed out of the first reverse V-shaped opening  51 . The stop plates  50  each have a first insertion hole  52  close to a circumferential edge of the first reverse V-shaped opening  51  for insertion of a measuring ruler  60 . The stop plates  50  each have a first through hole  531  and a second through hole  532  corresponding to the first positioning hole  471  and the second positioning hole  472  of the blade holder  40 , respectively. The first distance dl is defined from the first through hole  531  as well as the second through hole  532  to the base  10 . 
         [0030]    The chopping board  70  is fixed to the bottom sides of the first reverse V-shaped openings  51  of the stop plates  50 . Referring to  FIG. 7 , the chopping board  70  and the blade  48  are spaced to form a gap g when the blade holder  40  is lifted. 
         [0031]    The two covering plates  80  are erectly disposed at the two sides of the base  10  corresponding to the stop plates  50 . The stop plates  50  are screwedly locked to the covering plates  80 , respectively. The covering plates  80  each have a second reverse V-shaped opening  81  corresponding to the first reverse V-shaped openings  51  of the stop plates  50 . The covering plates  80  each have a second insertion hole  82  corresponding to the first insertion hole  52  for insertion of the measuring ruler  60 . The covering plates  80  each have a first retaining hole  831  and a second retaining hole  832  corresponding to the first through hole  531  and the second through hole  532  of each stop plate  50 . The fixing pin  90  is selectively inserted through the first retaining hole  831  and the first through hole  531  to the first positioning hole  471 , or the fixing pin  90  is selectively inserted through the second retaining hole  832  and the second through hole  532  to the second positioning hole  472 . The first retaining hole  831  and the second retaining hole  832  are calabash-shaped holes. The stop plates  50  are screwedly locked to the covering plates  80  through the top ends of the first retaining hole  831  and the second retaining hole  832 . The bottom ends of the first retaining hole  831  and the second retaining hole  832  are exposed out of the first through hole  531  and the second through hole  532 , respectively. The covering plates  80  each have a notch  84  relative to the base  10 . The covering plates  80  are screwedly locked to the base  10  through the first through hole  531 , the second through hole  532 , and the notch  84 . 
         [0032]    Referring to  FIG. 6  through  FIG. 9  in cooperation with  FIG. 13 ,  FIG. 1 , and  FIG. 2 , the fixing pin  90  is first pulled out and inserted into the working insertion hole  11 . The user can operate the paper corner protector cutter through the handle  30 . The connecting rod  31  is lifted by operating the handle  30  to move the operation rod  23  up. Through the drive shaft  231 , the operation rod  23  brings the drive block  49  to lift the blade holder  40  and the blade  48 . When the gap g between the blade  48  of the blade holder  40  and the chopping board  70  is exposed out of the first reverse V-shaped opening  51  and the second reverse V-shaped opening  81 , the user can insert the paper corner protector into the second reverse V-shaped opening  81  to cut the paper corner protector for a desired length by means of the measuring rule  60 . Finally, the handle  30  is pressed downward again to link the operation rod  23  and the blade holder  40  downward. Thereby, the paper corner protector is cut by the blade  48 , enabling the paper corner protector to be cut for the demand of various protects and applied to protect packing. 
         [0033]    Referring to  FIG. 3 , through the technical features that the drive block  49  is pivotally connected to the drive shaft  231  of the operation rod  23  through the through hole  491 ; the first width w 1  of the opening  41  is greater than the second width w 2  of the drive block  49 ; and the drive block  49  is slightly against the bottom side of the opening  41  and the flange  411 , the drive block  49  is able to slide eccentrically and transversely within the opening  41  and the handle  30  can be lifted longitudinally or down to press the blade holder  40  to keep the speed and precision for cuting the paper corner protector. 
         [0034]    The outer sides of the first plate  401  and the second plate  402  are longitudinally provided with the guide rails  46 , enabling the stop plates  50  to hold against the first plate  401  and the second plate  402  inwards so as to keep the structural strength of the paper corner protector cutter. When the blade holder  40  is lifted or pressed down, the guide rails  46  are adapted to decrease the friction area between the stop plates  50  and the first plate  401  as well as the second plate  402 , enhancing the utility of the paper corner protector cutter. 
         [0035]    Referring to  FIG. 6  and  FIG. 13 , when the handle  30  is pressed down, the first positioning hole  471 , the first through hole  531 , and the first retaining hole  831  are arranged concentrically, and the fixing pin  90  is inserted therein to secure the blade holder  40  for carrying and transporting the present invention conveniently through the handle  30 . 
         [0036]    Referring to  FIG. 5  and  FIG. 12  in cooperation with  FIG. 2 , when the user wants to replace the blade  48 , the covering plates  80  are lifted to disengage from the base  10  and the stop plates  50  through the insertion hole  83  and the notch  84 , such that the covering plates  80  are disassembled and the handle  30  is lifted for the second positioning hole  472 , the second through hole  532 , and the second retaining hole  832  to be arranged concentrically, the fixing pin  90  is inserted therein to position the blade holder  40  to be exposed out of the gap. At this time, the second screw member  4521  is loosened to release the disk-shaped elastic plate  4522  to decrease the prestressing force of the steel balls  4523  towards the blade  48 . The blade  48  is elastically positioned in the blade room  43  through the first screw member  442  and the tightening member  452  for the user to pull out the blade  48  easily and replace a new one. The new blade is elastically positioned in the blade room  43  for the user to adjust the position of the blade  48 . Finally, the second screw member  4521  is screwed to tighten the disk-shaped elastic plate  4522  for pushing the steel ball  4523  to hold against the blade  48  so as to secure the blade  48 . The blade  48  can be replaced quickly. 
         [0037]    Referring to  FIG. 10  and  FIG. 11 , the distal end of the handle  30  is provided with the J-shaped handle portion  32 , so that the user can grasp the handle portion  32  easily and smoothly to apply a force for operation. The handle portion  32  can be disassembled by dismantling the fixing pin  33  to reduce the size of the paper corner protector cutter for transportation. 
         [0038]    Although particular embodiments of the present invention have been described in detail for purposes of illustration, various modifications and enhancements may be made without departing from the spirit and scope of the present invention. Accordingly, the present invention is not to be limited except as by the appended claims.