Abstract:
The present invention is to provide a foldable knife operable with one single hand, which comprises a knife holder including a retaining space formed between a first plate and a second plate, a blade body having one end pivotally connected to one end of the knife holder and capable of being retained in the retaining space or rotated out of the retaining space, at least an actuating rod formed on one surface of the blade body; and an actuating portion formed on the first plate to cooperate with the actuating rod. When the knife body is retained in the retaining space, the actuating rod is aligned to the adjacent actuating portion adapted to push the actuating rod moving towards outside of the knife holder, thereby pushing the blade body out of the retaining space.

Description:
FIELD OF THE INVENTION  
       [0001]     The present invention relates to a foldable knife, more particularly to a foldable knife having an actuating portion adapted to push a blade body out of a retaining space of the foldable knife by one single hand of a user.  
       BACKGROUND OF THE INVENTION  
       [0002]     The currently commercially available foldable knife is illustrated in  FIG. 1 . The foldable knife  10  includes a knife holder  12  and a blade body  11 , wherein one end of the blade body  11  is pivotally connected with one end of the knife holder  12 . The blade body  11  can thus rotate about the knife holder  12 , thereby retaining the blade body  11  into a retaining groove  13  formed on one side of the knife holder  12 . When the user wants to open the foldable knife  10 , he/she must use one hand to hold the knife holder  12  and the other hand to pull the blade body  11  out of the retaining groove  13 , so as to pull out the knife blade  12 .  
         [0003]     However, the structural design of the conventional foldable knife  10  describe above requires the use of both hands to pull the blade body  11  out of the knife holder  12 . Under some special circumstances or for some emergency cases, the user can not pull out the foldable knife  10  with only one free hand. For example, if one hand of a diver were trapped by fishnet, he/she would not have both hands free to open the foldable knife  10  to cut off the fishnet. Therefore, the life of the diver will be threatened if the oxygen contained in the scuba can not sustain until he/she rescues himself/herself.  
         [0004]     Therefore, referring again to  FIG. 1 , some manufacturers of foldable knifes add a protrusively formed actuating rod  14  on both sides of the blade body  11 . When the blade body  11  is retained in the retaining groove  13 , the two actuating rods  14  provides the user the means to open the knife. Therefore, it is easy to rotate the blade body  11  out of the retaining groove  13  of the knife holder  12  by pushing the actuating rod  14  with only one hand.  
         [0005]     However, since modern people requires a more personal and artistic structural design for knifes, the two actuating rods  14  are often very small in size, so as to reduce their influence on the structural design. However, the smaller the actuating rod is designed, the harder for user to open the knife. Especially for those users of unskillful fingers, the force exerted on the small actuating rod often hurts the fingers of the users.  
         [0006]     Moreover, the two actuating rods  14  of the foldable knife  10  are often not exceeding the outer edge of the knife holder  12  for the convenience of carrying and for the overall design style. Therefore, when the user of the foldable knife  10  wants to push the actuating rod  14 , the force exerted on the actuating rod  14  forms an angle with the direction of the blade body  11  rotating away from the retaining groove  13 . The effective force that the user exerted to the actuating rod is thus small due to the presence of such an angle. Even worse, if the direction of the force that the user exerted on the actuating rod  14  is wrong, it is possible that the user can not rotate the blade body  11  out from the retaining groove  13 .  
         [0007]     For the above reasons, it is an important issue to design a foldable knife that is operable by one single hand, so as to enhance the functionality and the usefulness of the foldable knife, yet keeping the foldable knife of an artistic and esthetic style.  
       SUMMARY OF THE INVENTION  
       [0008]     In accordance with the background description set forth above, the inventors of the present invention have devoted themselves to the study and experimentation of foldable knifes with due diligence. Finally, a new foldable knife, which is the subject matter of the present invention, is developed.  
         [0009]     It is an object of the present invention to provide a foldable knife operable with one single hand. The foldable knife comprises a blade body and a knife holder. The knife holder includes a first plate and a second plate stacked on the first plate. A retaining space is formed between the first plate and the second plate, so as to retain the blade body therein. One end of the blade body comprises a sharp portion, while the other end of the blade body is pivotally connected to one end of the knife holder. In this manner, the blade body can be retained in the retaining space or can be rotated out of the retaining space. At least one surface of the blade body includes an actuating rod formed thereon. An actuating portion is formed on the first plate to cooperate with the actuating rod. When the knife body is retained in the retaining space, the actuating rod is aligned to the adjacent actuating portion. At this time, one can operate the actuating portion to push the actuating rod moving towards outside of the knife holder, thereby pushing the blade body out of the retaining space.  
         [0010]     It is another object of the present invention to form an elastic structure in the knife holder. When the actuating portion pushes the actuating rod and moves towards outside of the knife holder, the elastic structure can eject the blade body again out from the knife holder when the blade body is pushed out of the knife holder.  
         [0011]     It is yet another object of the present invention to provide a foldable knife that can reduce the force that the user needs to exert for rotating the blade body out of the knife holder. It is much easier to rotate the blade body out of the knife holder by operating the actuating portion to push the actuating rod than operating on the actuating rod directly.  
         [0012]     The above and other objects, features and advantages of the present invention will become apparent from the following detailed description taken with the accompanying drawings. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0013]      FIG. 1  is a perspective view of a conventional foldable knife.  
         [0014]      FIG. 2  is a perspective view of a foldable knife of the present invention.  
         [0015]      FIG. 3  is an explosive view of the foldable knife of the present invention.  
         [0016]      FIG. 4  is a side elevation of the foldable knife, in accordance with one aspect of the present invention.  
         [0017]      FIG. 5 a  side elevation of the foldable knife, in accordance with another aspect of the present invention.  
         [0018]      FIG. 6  is a sectional view of the foldable knife of the present invention before it is being folded.  
         [0019]      FIG. 7 a  sectional view of the foldable knife of the present invention after it is being folded. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0020]     Referring to  FIG. 2 , a foldable knife of the present invention includes a blade body  21  and a knife holder  30 , wherein the knife holder  30  is composed of a first plate  31  and a second plate  32  stacked with the first plate  31 . There is formed a retaining space  33  between the first plate  31  and the second plate  32 , so as to retain the blade body  21 . One end of the blade body  21  includes a sharp portion  22 , while the other end is pivotally connected to one end of the knife holder  30 . The blade body  21  can then be retained in the retaining space  33 , or rotated out from the retaining space. Moreover, at least one surface of the blade body  21  includes an actuating rod  23 , while an actuating portion  40  is formed on the first plate  31  incorporating with the actuating rod  23 . When the blade body  21  is retained in the retaining space, the actuating rod  23  is situated at the position of the actuating portion  40 , as shown in  FIG. 3  and  FIG. 4 . Referring now to  FIG. 5 , one can push the actuating rod  23  directly from operating the actuating portion  40 , so as to push the blade body  21  out from the retaining space  33 . In this manner, the blade body  21  is rotated out of the knife holder  30 .  
         [0021]     Referring again to  FIG. 2 , the side surfaces of one end of the blade body  21  is pivotally connected to the inner surfaces of one end of the knife holder  30  (i.e. the opposite surfaces of the first plate  31  and the second plate  32 ) via at least a pivot  34 , such that the blade body  21  can rotate about the center of the pivot  34 .  
         [0022]     Referring to  FIG. 2  and  FIG. 3 , the first plate  31  includes an upper cover  35  and a lower covered  36  stacked with the upper cover  35 . The actuating portion  40  is disposed between the upper cover  35  and the lower cover  36 . In addition, a guiding hole  45  is formed on one side of the first plate  31  facing the blade body  21  adjacent the actuating portion  40 . The guiding hole  45  provides one part of the actuating portion  40  to protrude therefrom. Furthermore, a sliding groove  41  is formed on the upper cover  35  corresponding to the actuating portion  40 . One end of a sliding piece  42  of the actuating portion  40  protrudes the first plate  31 , thereby providing users of the foldable knife to push thereon. The other end of the sliding piece  42  is restricted between the upper cover  35  and the lower cover  36 , such that the sliding piece  42  is moving smoothly when pushed.  
         [0023]     In addition, referring again to  FIG. 2  and  FIG. 3 , the actuating portion  40  further includes a foil  43 . The one end of the foil  43  and the other end of the foil  43  form a bending angle. The best bending angle is determined according to the position of the sliding groove  41  and the sliding track  44 . In this particular embodiment, the bending angle is between 30 degrees and 180 degrees. One end of the foil  43  is pivotally connected to one end of the knife holder  30 . In this manner, the other end of the foil  43  can be rotated about the center of the pivotal connections between the foil  43  and the knife holder  30  and protrudes the guiding hole  45 , thereby pushing the actuating rod  23 . The blade body  21  is then pushed out from the retaining space  33 . Further, a sliding track  44  is formed on the other end of the foil  43  so as to dispose the sliding piece  42  therein. Moreover, the sliding track  44  crosses the sliding groove  41 .  
         [0024]     Referring to  FIG. 4 , where an aspect of the knife holder  30  is illustrated. The foil  43  is retained in the knife holder  30 . The sliding piece  42  is situated in the sliding groove  41  away from the other end of the foil  43 . The sliding piece  42  is also situated in the sliding track  44  away from the other end of the foil  43 . Referring to  FIG. 5 , where another aspect of the knife holder  30  is illustrated. The sliding piece  42  moves along the sliding groove  41  towards the other end of the foil  43 . At the same time, the sliding piece  42  is situated in the sliding track  44  pushing the foil  43  to move. The sliding track  44  can thus move along the sliding piece  42 , so as to protrude the foil  43  out of the knife holder  30  and to push the actuating rod  23 .  
         [0025]     Referring to  FIG. 2 ,  FIG. 3 ,  FIG. 4 , and  FIG. 5 , the foil  43  in the present invention can be pivotally connected with the pivot  34 . In this manner, the foil  43  can rotate about the center of the pivot  34 . However, it is appreciated that the foil  43  can be pivotally connected to any position of the handle  30 . As long as the foil  43  can rotate within the knife holder so as to protrude part of the foil  43  out of the guiding hole  45  thereby pushing the actuating rod  23 , it is considered within the scope of the present invention.  
         [0026]     Referring again to  FIG. 3 , the actuating portion  40  further includes a recovery spring  46 . The recovery spring  46  is disposed between the upper cover  35  and the lower cover  36 . One end of the recovery spring  46  is connected with the sliding piece  42 , while the other end thereof is connected with the other end of the first plate  31  away from the pivot  34 . The recovery spring  46  is preferably disposed on the upper cover  35  (or the lower cover  36 ) directly facing the sliding groove  41 . In this manner, referring to  FIG. 4 , when the sliding piece  42  is situated in the sliding groove  41  away from the other end of the foil  43 , the pitch of the recovery spring  46  is denser. On the other hand, referring to  FIG. 5 , when the sliding piece  42  is moving in the sliding groove  41  towards the other end of the foil  43 , the pitch of the recovery spring  46  becomes looser, thereby generating an elastic recovery force. This elastic recovery force will be used to pull the sliding piece  42  back to the position in the sliding groove  41  away from the other end of the foil  43 . Thus, after the user of the foldable knife  20  pushes the sliding piece  42  to rotate out the blade body  21  from the knife holder  30 , the foil  43  and the sliding piece  42  can be recovered to their original position by taking advantage of the elastic recovery force.  
         [0027]     Referring again to  FIG. 3 , the knife holder  30  (as shown in  FIG. 2 ) includes an elastic structure  37 . When the actuating portion  40  pushes the actuating rod  23  to move towards outside of the knife holder  30  and the blade body  21  is pushed outside of the knife holder  30 , the elastic structure  37  can no longer eject the blade body  21  out of the knife holder  30 .  
         [0028]     Referring again to  FIG. 3 , the elastic structure  37  includes an actuating piece  24  and an elastic strip  38 , wherein the actuating piece  24  is disposed on the other end of the blade body  21 . A notch  25  is formed on the elastic piece  24 . The elastic strip  38  is extendedly disposed in the knife holder  30  (as shown in  FIG. 2 ). One end of the elastic strip  38  is disposed adjacent the actuating piece  24 . When the blade body  21  is rotated into the retaining space  33 , the edge of the actuating piece  24  having the largest outer radius will press the elastic strip  38 , thereby deforming the elastic strip  38  to reserve some elastic restoration force. Therefore, when the blade body  21  is rotated into the retaining space  33 , the user of the foldable knife  20  (as shown in  FIG. 2 ) can use only one hand to hold the knife holder  30  and use the thumb and the index finger to push the actuating rod  23 . In this manner, the actuating piece  24  starts rotating and gradually releases the pressing force of the elastic strip  38  until the elastic strip  38  extrudes into the notch  25 . Since the elastic strip  38  reserves the elastic restoration force through deformation, the restoration force is exerted to the notch  25  of the actuating piece  24 , thereby generating the torque for rotating the blade body  21  out of the retaining space  33 . The blade body  21  is then rapidly ejected out of the knife holder  30 .  
         [0029]     Referring to  FIG. 2  and  FIG. 3 , the surface of the second plate  32  facing the retaining space  33  includes an slightly bent elastic foil  54  formed thereon facing the blade body  21 . When the blade body is retained in the retaining space  32 , the surface of the blade body  21  press on the elastic foil  54  and deforms the elastic foil  54 . When the blade body  21  is rotated out of the retaining space, the elastic foil  54  will be recovered to its slightly bent shape, thus making the end point of the elastic foil  54  contacts the bottom edge of the blade body  21 . In this manner, the stability of the blade body  21  disposed on the knife holder  30  is enhanced. This can prevent the foldable knife  20  from accidentally cutting the fingers of the user when the blade body  21  rotates out abruptly. On the contrary, when the elastic foil  54  is deformed from pressing, the bottom edge of the blade body  21  can be released from the contact with the end point of the elastic foil  54 . At this time, the blade body  21  can be rotated into the retaining space  33 , and presses the elastic foil  54  again.  
         [0030]     Referring to  FIG. 3 , an extension foil  50  is extrusively formed on the foil  43  opposite to one end of the sliding track  44 . When the foil  43  rotates in the first plate  31  (as shown in  FIG. 2 ), the extension foil  50  also rotates between the upper cover  35  and the lower cover  36 . Further, a penetrating hole  52  is formed on one surface of the lower cover  36  facing the upper cover  35  and being between one end of the lower cover  36  adjacent the pivot  34  and the actuating portion  40 , so as to contain therein a locking element  51 . A positioning hole  53  is formed on one end of the blade body  21  opposite to the sharp portion  22  and facing one side of the first plate  31 . (The preferred position of the positioning hole  53  is between the actuating piece  24  and the actuating rod  23 .) In this manner, referring to  FIG. 3  and  FIG. 7 , the positioning hole  53  aligns with the penetrating hole  52  when the blade body  21  is retained in the retaining space, the sliding piece  42  is situated in the sliding groove  41  away from the other end of the foil  43 , and the sliding piece  42  is situated in the sliding track  44  away from the other end of the foil  43 . The extension foil  50  in the first plate  31  is also aligned to the penetrating hole  52 . Now that the locking element  51  contained in the penetrating hole  52  moves towards the retaining space when blocked by the extension foil  50  and enters the positioning hole  53 , so as to affix the blade body  21 .  
         [0031]     Under this condition, the actuating portion  40  is being operated and the foil  43  starts rotating. The blade body  21  is the driven to rotate out of the retaining space. Referring to  FIG. 3  and  FIG. 6 , the extension foil  50  is also driven to leave its original position. Now, the locking element  51  can move towards the upper cover  35  (or being blocked by the blade body  21  and moves towards the upper cover  35 ). The blade body  21  can then be rotated out of the retaining space. On the contrary, referring again to  FIG. 3  and  FIG. 7 , when the blade body  21  is retained in the retaining space  33 , the extension foil  50  is aligned to the penetrating hole  52  since the actuating portion  40  is not being operated. The locking element  51  is then pushed towards the retaining space  33 , whereby the locking element  51  can enter the positioning hole  53  to affix the blade body  21  when the blade body enters the retaining space  33 .  
         [0032]     While the invention has been described by means of specific embodiments, numerous modifications and variations could be made thereto by those skilled in the art without departing from the scope and spirit of the invention set forth in the following claims.