Patent Publication Number: US-7584640-B1

Title: Press brake tool

Description:
BACKGROUND 
   1. Field of the Invention 
   The present invention relates to mechanical technology and, particularly, to a press brake tool. 
   2. Description of Related Art 
   A press brake tool commonly includes a punch, and a die that defines a groove to receive the punch. 
     FIG. 5  shows a die  61  of a typical press brake tool. The die  61  defines an elongated V-shaped groove  62  and two elongated C-shaped grooves  63  on respective sides of the V-shaped groove  62 . The C-shaped grooves  63  are parallel to the V-shaped groove  62  and rotatably receive a cylindrical plug  64  therein. During punching, the cylindrical plugs  64  rotate in the C-shaped grooves  63  to reduce friction between the die  61  and a workpiece (not shown) in the die  61 , thereby protecting the workpiece from damage. 
   However, after being punched, the workpiece is manually removed from the die  61 , which is time-consuming. 
   Therefore, what is needed is to provide a press brake tool in which the described limitations are addressed. 
   SUMMARY 
   An exemplary press brake tool for bending a workpiece includes a punch having a punch tip, a press brake die, and a die holder for fixing the die thereto. The press brake die includes a pair of rotary members and at least one elastic member. The press brake die further defines an elongated lateral groove facing the punch tip and at least one longitudinal through hole communicating with the lateral groove. The pair of rotary members is spaced from each other and rotatably received in the elongated lateral groove. The at least one elastic member is received in the at least one longitudinal through hole, against the pair of the rotary members. 
   Other advantages and novel features of the present invention will become more apparent from the following detailed description of an embodiment/embodiments when taken in conjunction with the accompanying drawings. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a schematic view of a press brake tool according to an exemplary embodiment, showing a workpiece to be punched. 
       FIG. 2  is an exploded, isometric view of a press brake die of the press brake tool of  FIG. 1 . 
       FIG. 3  is an assembled view of a press brake die of the press brake tool of  FIG. 1 , in an idle position. 
       FIG. 4  is similar to  FIG. 3 , showing the press brake die in use. 
       FIG. 5  is a plan view of a typical die used in a press brake tool. 
   

   DETAILED DESCRIPTION 
   Referring to  FIG. 1 , a press brake tool  100  for bending a workpiece  200  in accordance with an exemplary embodiment includes a punch  10 , a press brake die  20 , and a die holder  30 . The punch  10  has a V-shaped punch tip  11 . The die  20  is fixed to the die holder  30 . The workpiece  200  is placed between the punch  10  and die  20 , and can be bent when the punch  10  descends into the die  20 . 
   Referring to  FIGS. 1 and 2 , the die holder  30  includes a base  32  and a receiving portion  34  extending perpendicularly from the base facing the die  20 . An elongated recess  36  is defined on a terminal of the receiving portion  34  facing the die  20 . 
   Referring to  FIGS. 2 to 4 , the die  20  includes an elongated protrusion  24  facing the die holder  30 , a pair of rotary members  40 , and a number of elastic members  50 . The elongated protrusion  24  is received in the elongated recess  36 . The die  20  defines an elongated lateral groove  22 , and a number of longitudinal through holes  23  communicating with the lateral groove  22  and functioning as extensions of the elastic members  50 . The lateral groove  22  includes a recessed portion  220  with a W-shaped extremity and two C-shaped sub-grooves  221 . The C-shaped sub-grooves  221  are respectively placed at opposite sides of the recessed portion  220 , and communicate with the recessed portion  220 . 
   The pair of rotary members  40  is spaced from each other, and a gap  43  is formed therebetween. The pair of rotary members  40  may form a configuration suitable for punching the workpiece  200  in response to the depression of the punch  10 . Each rotary member  40  includes a curved portion  42  rotatably received in a corresponding C-shaped sub-groove  221 , and an elongated contact portion  41  integrated with the arc portion  42 . The elongated contact portion  41  includes an upper surface  412  smoothly contacting the workpiece  200 , and a lower surface  414  opposite to the upper surface  412  abutting the elastic members  50  and subsequently received in the recessed portion  220  when the workpiece  200  is bent. 
   Each elastic member  50  includes a restore block  51  and an elastic element  52  e.g., a compression spring. An end of the restore block  51  abuts the lower surface  414  of the contact portion  41 , and the other end of the restore block  51  is connected to an end of the elastic element  52 . Another end of the elastic element  52  is fixed to the die holder  30 . In this way, the elastic members  50  impel the rotary members  40  to expel the punched workpiece  200  from the die  20 . 
   During a bending operation of the workpiece  200  (referring to  FIG. 1 ), the punch tip  11  descends into the die  20 . The workpiece  200  presses the two upper surfaces  412  of the contact portions  41 , and as a result, the pair of rotary members  40  rotate in the lateral groove  22  until the lower surface  414  is received and stopped in the recessed portion  220 . At this time, the restore blocks  51  of the elastic members  50  are pressed downwardly by the contact portion  41  using the lower surface  414 , thereby compressing the elastic elements  52 , and a V-shaped groove  44  is formed between the two upper surfaces  412  of the contact portions  41 . After the workpiece  200  is punched, the punch  10  moves upwardly. The elastic element  52  releases to impel the restore block  51  to an original position of the restore block  51 , and as a result, the pair of rotary members  40  rotates to eject the bent workpiece  200  from the die  20 . 
   The bent workpiece  200  can be automatically ejected by the pair of rotary members  40  of the press brake tool  100 . Therefore, the time for completing a bending operation of the workpiece  200  is reduced. 
   It is to be understood, however, that even though numerous characteristics and advantages of the present embodiments have been set forth in the foregoing description, together with details of the structures and functions of the embodiments, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.