Abstract:
The present invention discloses a folding knife that can be unfolded quickly, and its technology mainly resides on installing an elastic bar in a handle of the knife, and such elastic bar matches exactly with a groove hole on the blade body, so that during the process of rotating the blade body, the blade body can be rotated out from an open slot on one side of the handle quickly by the joint mechanism of the elastic bar and the groove hole.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a folding knife structure, more particularly to a folding knife structure that can be easily unfold with one hand. 
     2. Description of the Related Art 
     In general, a folding knife mainly comprises a handle and a blade body, wherein one end of the blade body is a pivotal connecting end, and such pivotal connecting end is pivotally coupled to one end of the handle, so that the blade body can be stored into an open slot disposed on one side of the handle. When a user wants to use the knife, the user has to hold the handle with one hand and use both of the index finger and the thumb of another hand to pull the blade body out from the open slot of the handle. However, the use of such folding knife requires both hands to take the blade body out from the handle. For special situations, if the user only can use one hand for the use, then such folding knife cannot be used. For example, if a user&#39;s hand is tangled by a rope or a net and tries to rescue himself/herself by cutting the rope or the net immediately, or if one of the user&#39;s hands is injured and leaves the user one hand to use the knife, then the user will fall into an embarrassing situation of not able to use such folding knife. 
     Manufacturers aim at the above shortcomings to develop a spring knife as shown in FIG.  1 . Such spring knife  2  comprises a hollow handle  20 , an opening disposed on one side of the handle  20 , a blade body  21  disposed in the handle  20 , a blade section  211  disposed on an appropriate position of one side of the blade body  21 , and a pivotal connecting section  212  at one end of the handle  20  for pivotally coupling to an axial rod  22  disposed at one end of the handle  20 , an elastic member  23  coupled to the blade body  21  and disposed in the handle  20 , and a press switch  24  disposed in the handle  20  proximate another side of the blade body  21  and adjacent to a position proximate the axial rod  22 , so that when the user presses the press switch  24 , the blade body  21  is released from the latch and the elasticity of the elastic member  23  drives the blade body  21  to rotate along the axis of the axial rod  22  and rotate the blade body  21  out from the handle  20 . In other words, a user only needs one hand to operate the spring knife  2  easily and quickly. 
     However, the press switch  24  protrudes from an obvious exposed position on the surface of the handle  20 . Under situations of negligence or the knife being played by a child, the blade body  21  may be opened by touching the press switch  24 . As a result, it may cause accidents or injuries, which turns the original intention of the design into a danger. 
     In view of the inconvenience on the use of traditional folding knives, an improved spring knife was introduced. Although the spring knife can overcome the inconvenience of the traditional folding knife, the blade body of the spring knife may spring out from the handle and hurt innocent people by touching the press switch by mistake. Therefore, the inventor of the present invention performed a series of studies and experiments to overcome the shortcomings of the prior art and finally invented the folding knife structure of the present invention. 
     SUMMARY OF THE INVENTION 
     The primary objective of the present invention is to provide a folding knife that can be unfolded quickly, and its technology mainly resides on installing an elastic bar in a handle, and such elastic bar can exactly match with a groove hole on the blade body, so that the blade body can be rotated out from an open slot on one side of the handle quickly by the joint mechanism of the elastic bar and the groove hole during the process of rotating the blade body. 
     Another objective of the present invention is to provide a folding knife that can be unfolded by one hand. In addition to the structure described above, a poke rod is installed each on both sides of the blade body such that when a user uses one hand to hold the handle and uses the index finger or the thumb to push the poke rod, the blade body will spring out from the open slot of the handle quickly. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Other features and advantages of the present invention will become apparent in the following detailed description of the preferred embodiments with reference to the accompanying drawings, in which: 
     FIG. 1 is a perspective diagram of the disassembled parts of a traditional spring knife. 
     FIG. 2 is a perspective diagram of the assembled structure of the present invention. 
     FIG. 3 is a perspective diagram of the disassembled parts of the present invention. 
     FIG. 4A is the first illustrative diagram of the movement of the present invention. 
     FIG. 4B is the second illustrative diagram of the movement of the present invention. 
     FIG. 4C is the third illustrative diagram of the movement of the present invention. 
     FIG. 4D is the fourth illustrative diagram of the movement of the present invention. 
     FIG. 4E is a fifth illustrative diagram of the movement of the present invention. 
     FIG. 4F is the sixth illustrative diagram of the movement of the present invention. 
     FIG. 5 is a perspective diagram of a preferred embodiment of the present invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Refer to FIGS. 2 and 3 for a folding knife structure according to the present invention, which comprises a blade body  3 , having a blade tip  31  and a blade handle  32  on both ends, a blade back  33  and a blade  34  respectively on both corresponding sides, wherein the blade handle  32  has a pivotal connecting end  321  (such as a circular hole), and the pivotal connecting end  321  is pivotally coupled to a pivotal connecting element  43  (such as an axial pillar) disposed on one end of the knife handle  4  such that the blade body  3  is received into or sprung out from an open slot  44  disposed on one side of the knife handle  4 . Further, a groove hole  35  is disposed on the blade body  3  at a position adjacent to the blade  34  along the pivotal connecting end  321 , and a separating point  351  is protruded from one inner edge of the groove hole  35  proximate the pivotal connecting end  321 , and a first pressing section  352  is disposed on one side of the separating point  351  adjacent to the blade  34  and a second pressing section  353  is disposed on the side away from the blade  34 . An elastic bar  5  is disposed on the inner surface  411  of the adjacent knife handle  4 , and one end of the elastic bar  5  is extended and bent into a bending section  51  in the groove hole  35 . 
     Please refer to FIGS. 2 and 3 for the present invention. When the elastic bar  5  is not deformed, both ends of the elastic bar  5  are bent towards the middle, and both ends are closer to the open slot  44  than the middle. When the blade body  3  is folded into the open slot  44 , the elastic bar  5  will produce a larger deformation (changing from the status of having larger curvature to the status of a smaller curvature) and provides better elasticity for the restoration. 
     Please refer to FIGS.  4 A˜ 4 F for the illustrative diagrams of the movement. When the blade body  3  is stored into the open slot  44 , the first pressing section  352  exactly pushes the bending section  51 , so that the elastic bar  5  will deform and maintain an appropriate elastic restoration (as shown in FIG.  4 A). At that time, if the blade body  3  uses such pivotal connecting element  43  as an axis to apply an appropriate external force in the direction away from the knife handle  4 , since the groove hole  35  is set on the blade body  3 , therefore the groove hole  35  will start shifting along the pivotal connecting element  43  as shown in FIG. 4B, such that the separating point  351  will slide through the bending section  51  (that is the appropriate external force can release the mutual pressing situation between the first pressing section  352  and the bending section  51 ) until the bending section  51  and the second pressing section  353  are in contact with each other as shown in FIG.  4 C. The elastic bar  5  starts pushing the second pressing section  353  (as shown in FIGS. 4D and 4E) by the elastic restoration force produced by the deformation, so that the blade body  3  can use the pivotal connecting element  43  as an axis to start moving away from the open slot  44  and rotating out from the knife handle  4  (as shown in FIGS.  2  and  4 F). 
     On the other hand, when the knife body  3  is completely extended out from the knife handle  4  (as shown in FIGS.  2  and  4 F), if the knife body  3  uses the pivotal element  43  as an axis to exert an appropriate external force at a position proximate the open slot  44 , the groove hole  35  will shift along the pivotal connecting end  321  as shown in FIGS. 3,  4 D and  4 E) to drive the second pressing section  353  to push the ending section  51 , so that the elastic bar  5  start generating a deformation (as shown in FIG.  4 C). When the separating point  351  slides through the bending section  51 , the bending section  51  and the first pressing section  352  are in contact with each other (as shown in FIG.  4 B). Then, the elastic bar  5  starts pushing the first pressing section  352  by the appropriate elastic restoration force of the elastic bar  5 , so that the blade body  3  can use the pivotal connecting element  43  as an axis to start moving towards the open slot  44  until the blade body  3  is completely stored into the open slot  44  (as shown in FIG.  4 A). 
     Please refer to FIGS. 2 and 3 for the present invention. The knife handle  4  comprises a casing  41 , another casing  42 , and a back cover  45  coupled to each other by a plurality of connecting elements  61  and another connecting elements  62  (such as a bolt and a nut), wherein the back cover  45  is installed on a corresponding side between the casings  41 ,  42 . Since the back cover  45  has a specific thickness (slightly thicker than the blade body  3 ) so that the casings  41 ,  42  are kept in an appropriate distance apart to define the open slot  44 . 
     Please refer to FIG. 3 for the present invention. The inner surface  411  of the casing  41  has an accommodating groove  412  for installing the elastic bar  5  into the accommodating groove  412 . A fixed plate  7  is fixed onto the inner surface  411 ; a curved hole  71  is disposed on one end adjacent to the pivotal connecting end  321 ; a limit section  72  is disposed at a position adjacent to the curved hole  71 ; and another limit section  73  is disposed at a position away from the curved hole  71 , so that when the fixed plate  7  is covered onto the inner surface  411 , the elastic bar  5  will be fixed into the accommodating groove  412  and limited by the limit sections  72 ,  73  to serve as a fulcrum for the deformation. Further, the bending section  51  is exposed outside the fixed plate  7  from the curved hole  71 , such that the bending section  51  will be located in the groove hole  35  after the casing  41 , another casing  42 , and the blade body  3  are mutually coupled as a whole. 
     Please refer to FIGS. 2 and 3 again for the present invention. In the open slot  44 , a stop element  8  is disposed at a position adjacent to another casing  42 , and the stop element  8  is elastically bent slightly toward the middle of the open slot  44 , so that after the blade body  3  is rotated completed out from the open slot  44 , the stop element  8  will press exactly on one side of the blade handle  32  to stop the blade body  3  from being rotated into the open slot  44 . On the contrary, after the blade body  3  is received into the open slot  44 , an appropriate external force is applied on the stop element  8  in a direction towards another casing  42  (i.e. releasing the mutual pressing situation between the stop element  8  and the blade handle  32 ), an appropriate external force will be applied onto the blade body  3  in the direction towards the open slot  44  to store the blade body  3  into the open slot  44 . 
     Please refer to FIGS. 2 and 3 for the present invention. Based on the concept of ergonomic design, a poke rod  36  is set respectively on a position on one surface of the blade body  3  and a position adjacent to the blade back  33 . By such design, when the blade body  3  is stored in the open slot  44 , the user only needs to hold the knife handle  4  with the palm and use the thumb to push the poke rod  36 , and then an appropriate external force in the direction away from the knife handle  4  will be exerted onto the blade body  3  such that the blade body  3  will quickly move away from the open slot  44  and extend outside the knife handle  4  until the poke rod  36  and the knife handle  4  are in contact with each other. At that time, if the stop action of the stop element  8  is put into effect, then the blade body  3  is secured onto one end of the knife handle  4 . On the contrary, when the blade body  3  is stored into the open slot  44 , since the poke rods  36  exactly press against the stop element  8 , the blade  34  will not be in direct contact with the back cover  45  in the process of storing the blade body  3  into the open slot  44 , therefore it can prevent the back cover  45  from being cut and damaged by the blade  34 , an thus can maintain the sharpness of the blade  34 . 
     Please refer to FIGS. 2 and 5. There are various modifications for setting the groove boles  35  on the blade body  3 , as long as the groove hole  35  has a separating point  351  protruded on an inner edge of a pivotal connecting end  321  adjacent to the groove hole  35  and two sides of the separating point  351  are disposed respectively on the first pressing section  352  and the second pressing section  353 . For example, a substantially half-moon shaped through hole (as shown in FIG. 5) is passed through by the blade body  3  or a indented groove (as shown in FIG. 2) is set on the one end of the blade body  3  towards the inner edge of the pivotal connecting end  321 . Therefore, any variation or modification that can easily be made by the person skilled in the art is included within the scope of the claims of this invention. 
     While the present invention has been described by the most practical and preferred embodiments, it is understood that this invention is not limited to the disclosed embodiments but is intended to cover various arrangements included within the spirit and scope of the broadest interpretations and equivalent arrangements.