Patent Publication Number: US-6709320-B2

Title: Width adjustable sharpener

Description:
FIELD OF THE INVENTION 
     The present invention relates to a knife sharpener that has two pivotable grinding members each of which has a rod pivotably engaged with a shaft, a width between the two grinding members is adjustable by rotating the shaft. 
     BACKGROUND OF THE INVENTION 
     A conventional knife sharpener is shown in FIG.  4  and includes a handle  1  and a head  11  in which a V-shaped groove  12  is defined. The two opposite insides  13  of the groove  12  are made by a material that is harder than the material of knives. A blade of a knife (not shown) is inserted in the groove  12  and two sides of the edge of the blade contact the two insides  13  of the groove  12  so that when moving either the blade of the sharpener  1 , the edge of the blade is sharpened. Nevertheless, the width of the groove  12  is fixed so that only the blade that has a thickness suitably received in the groove  12  can be sharpened by the sharpener. A knife that has a blade with too thick or too thin blade cannot be sharpened by the sharpener. In other words, the users should prepare at least two sharpeners so as to sharpen all the knives they have. 
     SUMMARY OF THE INVENTION 
     In accordance with one aspect of the present invention, there is provided a knife sharpener which comprises a handle and an operation portion in which a chamber is defined so as to receive two grinding members therein. An aperture is defined through a top of the operation portion and communicates with the chamber. 
     Each of the two grinding members has a grinding surface and an angle is defined between the two respective grinding surfaces. A rod extends radially outward from each of the grinding members. 
     A passage is defined in the operation portion and a shaft is rotatably received in the passage. Two spiral grooves are defined in an outer surface of the shaft and the two respective rods are engaged with the two spiral grooves. A positioning member is engaged with the shaft. 
     The primary object of the present invention is to provide a knife sharpener wherein the width between two grinding members can be adjusted so as to sharpen knives with different thickness. 
     The present invention will become more obvious from the following description when taken in connection with the accompanying drawings which show, for purposes of illustration only, a preferred embodiment in accordance with the present invention. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a cross sectional view to show the knife sharpener of the present invention; 
     FIG. 2 is a perspective view to show the knife sharpener of the present invention; 
     FIG. 3 is a perspective view to show a peeler is engaged with a top of the operation portion of the knife sharpener of the present invention, and 
     FIG. 4 is a perspective view to show a knife sharpener. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring to FIGS. 1 and 2, the knife sharpener  2  of the present invention comprises a handle  20  and an operation portion  21  in which two chamber  23  are defined. Two apertures  22  are defined through a top of the operation portion  21  and communicate with the chambers  23 . A receiving chamber  200  is defined in the handle  20  and a peeler  201 , for example, is received in the receiving chamber  200 . A fastening member  7  is connected on a top of the operation portion  21  so that the peeler  201  can be pivoted out from the receiving chamber  200  and is secured by the fastening member  7  as shown in FIG.  3 . The user may hold the handle  20  and peel fruits. 
     Two grinding members  4  are respectively and pivotably received in each of the chambers  23  and each of the grinding members  4  has a grinding surface  41 . The two grinding surfaces  41  face to each other and an angle is defined between the two respective grinding surfaces  41  and communicates with the aperture  22 . Therefore, a blade may be put between the two grinding surfaces  41  to be sharpened. Each of the two grinding members  4  has a rod  43  extending radially therefrom. 
     A passage  25  is defined in the operation portion  21  and a shaft  3  is rotatably received in the passage  25 . Two pairs of spiral grooves  31  are defined in an outer surface of the shaft  3 . Each of the chambers  23  has a hole  24  which communicates with the passage  25  and the two respective rods  43  extend through the holes  24  and are engaged with the two spiral grooves  31 . A knob  3  is connected to an end of the shaft  3  and is accessible from outside of the operation portion  21 . Therefore, the user may rotate the shaft  3  by controlling the knob  3 . The shaft  3  has a plurality of recesses  32  defined therein. 
     A positioning member  5  which is a pin extends through a hole  26  defined through the top of the operation portion  21 . A clip  61  is secured on the positioning member  5  and a spring  6  is mounted on the positioning member  5 . The spring  6  is biased between the clip  61  and an inside  210  of the operation portion  21 . A lower end of the positioning member  5  is received in one of the recesses  32  to position the shaft  3 . When the positioning member  5  is lifted to remove the lower end of the positioning member  5  from the recess  32 , the shaft  3  is able to be rotated. The rods  43  of the grinding members  4  are then shifted and the grinding members  4  are rotated to adjust the angle and the width between the two grinding surfaces  41  so as to fit different thickness of knives. 
     Two support legs  29  are connected to an underside of the sharpener  2  and a grinding piece  28  is connected to an underside of the operation portion  21 . A lower end of the grinding piece  28  is shorter than the support legs  29 . The grinding piece  28  allows the user to have different options to sharpen knives. 
     While we have shown and described the embodiment in accordance with the present invention, 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.