Patent Publication Number: US-6336272-B1

Title: Scissors structure

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a scissors structure. 
     2. Description of the Related Art 
     A conventional scissors structure  50  in accordance with the prior art shown in FIG. 8 comprises two pivotally connected blades  51 , two handles  54 , a locking pin  52  secured on one of the two blades  51 , a recessed locking piece  53  pivotally mounted on the other blade  51  and detachably locked on the locking pin  52 , and a spring  55  mounted between the two handles  54 . 
     However, connection between the locking piece  53  and the locking pin  52  is not stable so that the locking piece  53  is easily detached from the locking pin  52  so that the two handles  54  of the scissors structure are easily expanded even when not in use, thereby affecting the locking effect of the scissors structure. In addition, the scissors structure is in use, the locking piece  53  is suspended on the blade  51  as shown in phantom lines so that the locking piece  53  is easily in contact with the handles  54 , thereby greatly influencing the operation of the handles  54  and the cutting action of the blades  51 . 
     The closest prior art of which the applicant is aware is disclosed in U.S. Pat. No. 5,297,343 to Melter et al., filed on Jan. 7, 1993, entitled by “Trimming scissors and sheath assembly”. 
     When the scissors are in use, the two handles  24  and  28  are separated from each other and the lock button  20  is attached to the handle  24 . However, the lock button  20  freely slidable on the rails  68  and  70  is easily moved forward, thereby easily hindering the relative movement between the two handles  24  and  28  while the lock button  20  is easily broken when the two handles  24  and  28  are moved toward each other, thereby decreasing the lifetime of the scissors  10 . In addition, the compression spring  18  mounted on the rear end of the lock button  20  is located away from the pivot point of the two handles  24  and  28 , thereby easily clipping or injuring the user&#39;s hand. Further, the compression spring  18  is mounted on the rear end of the lock button  20  and is located away from the pivot point of the two handles  24  and  28  so that the tension of the two handles  24  and  28  of the scissors  10  is not efficient. 
     SUMMARY OF THE INVENTION 
     In accordance with one aspect of the present invention, there is provided a scissors structure comprising: 
     a first blade portion including a first handle defining a first chamber having a front end provided with a first locking stub and a rear end provided with a T-shaped first guide rail, the first guide rail having a front end provided with a first guide track located adjacent to the first locking stub and a rear end defining an access opening; 
     a second blade portion pivotally mounted on the first blade portion and including a second handle defining a second chamber having a front end provided with a second locking stub and a rear end provided with a T-shaped second guide rail provided with a second guide track, at least one snapping boss mounted on the second guide rail and aligning with the access opening of the first guide rail; 
     a restoring spring mounted between the first handle and the second handle and having a first end secured to the first locking stub and a second secured to the second locking stub; and 
     a substantially I-shaped locking member slidably mounted between the first guide rail and the second guide rail and having two sides each provided with a T-shaped guide slot for receiving the first guide track of the first guide rail and the second guide track of the second guide rail, the guide slot having two sides each provided with an inward folded retaining flange for limiting the first guide track of the first guide rail and the second guide track of the second guide rail, the retaining flange defining at least one positioning notch for detachably locking the at least one snapping boss. 
     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 scissors structure in accordance with the present invention; 
     FIG. 2 is an exploded view of the scissors structure as shown in FIG. 1; 
     FIG. 3 is a top plan operational view of the scissors structure as shown in FIG. 1; 
     FIG. 4 is a top plan view of the scissors structure as shown in FIG. 1; 
     FIG. 5 is a side plan cross-sectional view of the scissors structure along the line  5 — 5  as shown in FIG. 4; 
     FIG. 6 is a side plan cross-sectional view of the scissors structure along the line  6 — 6  as shown in FIG. 4; 
     FIG. 7 is a side plan cross-sectional view of the scissors structure along the line  7 — 7  as shown in FIG. 3; and 
     FIG. 8 is a perspective view of a conventional scissors structure in accordance with the prior art. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring to the drawings and initially to FIGS. 1-3, a scissors structure in accordance with the present invention comprises a first blade portion  10 , a second blade portion  20 , a restoring spring  40 , and a substantially I-shaped locking member  30 . 
     The first blade portion  10  includes a first blade  11 , and a first handle  12  mounted on the first blade  11 . The first handle  12  defines a first chamber  13  having a front end provided with a first locking stub  15  and a rear end provided with a T-shaped first guide rail  14 . The first guide rail  14  has a front end provided with a first guide track  141  located adjacent to the first locking stub  15  and a rear end defining an access opening  142 . 
     The second blade portion  20  is pivotally mounted on the first blade portion  10  and includes a second blade  21 , and a second handle  22  mounted on the second blade  21 . The second handle  22  defines a second chamber  23  having a front end provided with a second locking stub  25  and a rear end provided with a T-shaped second guide rail  24  provided with a second guide track  241 . At least one snapping boss  242  is mounted on the second guide rail  24  and aligns with the access opening  142  of the first guide rail  14 . 
     The restoring spring  40  is mounted between the first handle  12  and the second handle  22  and has a first end secured to the first locking stub  15  and a second secured to the second locking stub  25 . 
     The locking member  30  is slidably mounted between the first guide rail  14  and the second guide rail  24  and has two sides each provided with a T-shaped guide slot  31  for receiving the first guide track  141  of the first guide rail  14  and the second guide track  241  of the second guide rail  24 . The guide slot  31  has two sides each provided with an inward folded retaining flange  32  for limiting the first guide track  141  of the first guide rail  14  and the second guide track  241  of the second guide rail  24 . The retaining flange  32  defines at least one positioning notch  321  for detachably locking the snapping boss  242  therein. 
     The locking member  30  is provided with a plurality of a plurality of elongated ribs  33  protruding outward for increasing friction of the locking member  30 . 
     Alternatively, the positioning notch  321  defined in the retaining flange  32  and the snapping boss  242  formed on the second guide rail  24  can be interchangeably mounted. In other words, the positioning notch is defined in the second guide rail  24 , and the snapping boss  242  is formed on the retaining flange  32 . 
     In operation, referring to FIGS. 1-7, the snapping boss  242  is initially locked in the positioning notch  321  so that the locking member  30  is stably secured on the second guide rail  24  of the second handle  22  as shown in FIGS. 3 and 7. In such a manner, the first handle  12  and the second handle  22  are pressed outward relative to each other by means of the restoring spring  40 , thereby expanding the scissors structure for use. 
     When not in use, the user&#39;s hand can exert a force on the first handle  12  and the second handle  22  which are moved toward each other so as to move the locking member  30  toward the first guide rail  14  until the retaining flange  32  of the guide slot  31  of the locking member  30  is inserted into the access opening  142  of the first guide rail  14 . The locking member  30  is then moved toward the restoring spring  40  to the position as shown in FIG. 4 where the first guide track  141  of the first guide rail  14  is received in the guide slot  31  of the locking member  30  and is limited by the retaining flange  32  of the guide slot  31  of the locking member  30  so that the first handle  12  and the second handle  22  are secured by the locking member  30  as shown in FIG. 6 while the restoring spring  40  is compressed between the first handle  12  and the second handle  22 , thereby folding the scissors structure. 
     Accordingly, the scissors structure of the present invention has the following advantages. 
     1. The locking member  30  can be used to lock the scissors structure when it is folded. 
     2. When the first handle  12  and the second handle  22  are separated from each other, the snapping boss  242  is locked in the positioning notch  321  so that the locking member  30  is secured on and cannot be detached from the second guide rail  24  of the second handle  22 , thereby preventing the locking member  30  from freely sliding forward on the guide track  241  to hinder the relative movement between the first handle  12  and the second handle  22  and to hinder the cutting operation of the scissors structure, and thereby preventing the locking member  30  being hit or broken when the first handle  12  and the second handle  22  are moved toward each other so as to increase the lifetime of the scissors structure. 
     3. The restoring spring  40  is mounted on the front end of each the two handles  12  and  22 , thereby preventing the user&#39;s hand being clipped or injured by the restoring spring  40 . 
     4. The restoring spring  40  is mounted on the front end of each the two handles  12  and  22 , thereby increasing the tension of the two handles  12  and  22  of the scissors structure. 
     It should be clear to those skilled in the art that further embodiments may be made without departing from the scope of the present invention.