Patent Publication Number: US-2023158627-A1

Title: Electric knife sharpener

Description:
RELATED APPLICATIONS 
     This application is a continuation-in-part of U.S. patent application Ser. No. 17/545,473, filed on Dec. 8, 2021 and entitled “ELECTRIC KNIFE SHARPENER”. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a cutting tool grinding device, especially an electric knife sharpener. 
     2. Description of the Related Art 
     Taiwan Patent M574952 discloses an electric knife sharpener. Each sharpening component of this electric sharpener has a pivot hole, and two sharpening components are used as a group, and each pair of sharpening components is pivotally connected to the upper end of a linkage unit. Since there is a stop in the middle of the knife groove, because the two sharpening components are pivotally connected to the same pivot point, the sharpening components will form a separation and clamping action when it is actuated, so it can only be ground on one side. This method is a clip-on method. The blade of the knife ground by this method is not sharp and the appearance is not beautiful. Since the knife can only be sharpened on one side, it often takes a lot of time to trim and grind both sides of the blade. Therefore, the lack of conventional electric knife sharpeners still needs to be improved. 
     SUMMARY OF THE INVENTION 
     The present invention has been accomplished under the circumstances in view. It is the main object of the present invention to provide an electric knife sharpener, wherein the sharpening components of the grinding unit and the linkage unit of the electric knife sharpener can provide a better displacement angle grinding effect. 
     In order to achieve the above object, the present invention proposes an electric knife sharpener, which comprises an accommodating unit, a driving unit, a linkage unit, and a grinding unit. The accommodating unit comprises an upper cover and a base. The upper cover has an opening slot. The driving unit comprises a motor and an eccentric wheel. The driving unit is fixed on the base. The linkage unit comprises a linkage mechanism and an upper fixing seat. The upper fixing seat is set in the upper cover below the opening slot. The upper fixing seat comprises two limiting rods. Each limiting rod is set in the upper fixing seat. The linkage mechanism comprises a pivot end inserted in the upper fixing seat. The linkage mechanism is drivable by the eccentric wheel to reciprocate along an axial direction. The grinding unit comprises two sharpening components. Each sharpening component has an arc-shaped oblique hole. The limiting rods of the upper fixing seat are respectively inserted through the arc-shaped oblique holes. Each sharpening component has one end thereof pivotally connected to the pivot end of the linkage mechanism. The two sharpening components are pivoted at different pivot points, so that the two sharpening components form a cross arrangement and opposite openings are formed between the two sharpening components to cross a sharpening accommodating space. The two sharpening components are exposed in the opening slot of the upper cover. 
     With the cooperation of the driving unit, the linkage unit and the grinding unit, the cutting tool can be double-sided grinding at the same time, thereby making the blade sharp and beautiful, and shortening the time required for sharpening, thus achieving the object of the present invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is an oblique top elevational view of the first preferred embodiment of the present invention, showing the state of the present invention installed in an accommodating unit. 
         FIG.  2    is an exploded view of the first preferred embodiment of the present invention. 
         FIG.  3    is a bottom view of the first preferred embodiment of the present invention, showing the internal state of the accommodating unit. 
         FIG.  4    is a sectional view taken along line  4 - 4  of  FIG.  1   . 
         FIG.  5    is a sectional view taken along line  5 - 5  of  FIG.  1   . 
         FIG.  6    is similar to  FIG.  5   , and is a schematic view of the action of the first preferred embodiment of the present invention. 
         FIG.  7    is an exploded view of the second preferred embodiment of the present invention. 
         FIG.  8    is a sectional view taken along line  8 - 8  of  FIG.  7   . 
         FIG.  9    is a sectional view taken along line  9 - 9  of  FIG.  7   . 
         FIG.  10    is similar to  FIG.  9   , and is a schematic view of the action of the second preferred embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     In order to describe in detail the technical features of the present invention, the following preferred embodiment is described in conjunction with the drawings. 
     Referring to  FIG.  1    to  FIG.  6   , a first embodiment of the present invention discloses an electric knife sharpener  10 . The electric knife sharpener  10  is mainly composed of an accommodating unit  11 , a driving unit  21 , a linkage unit  31 , and a grinding unit  41 . 
     The accommodating unit  11  comprises an upper cover  111  and a base  112 , as shown in  FIG.  3   , and the upper cover  111  has an opening slot  113 . 
     The driving unit  21  comprises a motor  71  and an eccentric wheel  81 , and the driving unit  21  is fixed on the base  112 . 
     The linkage unit  31  comprises a linkage mechanism  61  and an upper fixing seat  51 . The upper fixing seat  51  has two limiting rods  511 , and each of the limiting rods  511  is pivotally connected to the upper part of the upper fixing seat  51  in parallel. The linkage mechanism  61  has a pivot end  611  and a driving end  612 , and the pivot end  611  penetrates through a through hole  513  of the upper fixing seat  51 . The through hole  513  is provided with two guiding blocks  512 , and the two guiding blocks  512  are arranged on opposite sides of the through hole  513 . The pivot end  611  has a guide groove  614 , and both ends of the guide groove  614  are respectively connected with the guiding blocks  512 . The linkage mechanism  61  of the linkage unit  31  can be driven by the eccentric wheel  81  to move upward and downward along an axial direction. 
     The grinding unit  41  comprises two sharpening components  412 , and each of the sharpening components  412  is provided with an arc-shaped oblique hole  41 . The two arc-shaped oblique holes  413  are bent and expanded in opposite directions. The two arc-shaped oblique holes  413  are limited to a limiting rod  511  in the linkage unit  31 . One end of each sharpening component  412  is pivotally connected in a groove of the linkage mechanism  61 . The two sharpening components  412  are pivotally connected to different pivot points, so that the two sharpening components  412  form a cross arrangement and opposite openings are formed between the two sharpening components to cross a sharpening accommodating space, and the two sharpening components  412  are exposed in the opening slot  113  of the upper cover  111 . 
     The driving unit  21  is installed on the base  112 , and the upper cover  111  and the upper fixing seat  51  are screwed together. 
     As shown in  FIGS.  5  to  6   , one end of each sharpening component  412  is pivotally connected to the linkage mechanism  61 , and the two limiting rods  511  of the linkage unit  31  are respectively passed through the two arc-shaped oblique holes  413  of the grinding unit  41 . When the driving unit  21  drives the linkage unit  31  to act, the linkage mechanism  61  moves upwards to push the two sharpening components  412  of the grinding unit  41  upwards to expand along the shape of the arc-shaped oblique holes, and when the linkage mechanism  61  moves downward, it pushes the two sharpening components  412  downwards to condense in a reciprocating motion. 
     It can be seen from the above that the electric knife sharpener  10  of the present invention, compared with the previous clip-on technology, can indeed make the blade of the knife sharper and more beautiful, and shorten the time required for sharpening. In this way, the problems encountered by the aforementioned conventional technologies can be solved. 
     Referring to  FIG.  7    to  FIG.  10   , the electric knife sharpener of the second embodiment of the present invention composes an accommodating unit  11 , a driving unit  21 , a linkage unit  31 , and a grinding unit  41 . 
     The accommodating unit  11  comprises an upper cover  111  and a base  112 , and the upper cover  111  has an opening slot  113 . 
     The driving unit  21  comprises a motor  71  and an eccentric wheel  81 . 
     The linkage unit  31  comprises a linkage mechanism  61 . The linkage mechanism  61  has a pivot end  611  and a driving end  612 . The driving end  612  is provided with a ring, and the eccentric wheel  81  is arranged in the ring of the driving end  612  so that the link mechanism  61  can be driven by the eccentric wheel  81  to move up and down in an axial direction. In this embodiment, the two limiting rods  511  are disposed at the position where the upper cover  111  is close to the opening sipe  113 . 
     The grinding unit  41  comprises two sharpening components  412 , and each of the sharpening components  412  is provided with an elongated oblique hole  413 . Each of the two elongated oblique holes  413  is correspondingly limited to one respect limiting rod  511  to move. One end of each sharpening component  412  is pivotally connected to the pivot end  611  of the linkage mechanism  61 . The two sharpening components  412  are pivotally connected to different pivot points, so that the two sharpening components  412  form a cross arrangement and opposite openings are formed between the two sharpening components to cross a sharpening accommodating space, and the two sharpening components  412  are exposed in the opening slot  113  of the upper cover  111 . 
     Although the second embodiment of the present invention is different from the first embodiment in appearance, its structural and functional essence is the same as that of the first embodiment. The difference between the structure of the second embodiment of the present invention and the previous embodiment is that in the second embodiment, the linkage unit  31  is not provided with an upper fixing seat, and the two limit rods  511  originally provided in the upper fixing seat are set in the upper cover  111 . The sharpening components  412  are also correspondingly disposed on the two limit rods by using their elongated oblique holes. Therefore, when the eccentric wheel  81  drives the linkage mechanism  61  to move up and down, the linkage mechanism  61  will drive the two sharpening components  412  to move up and down, and the two sharpening components  412  are also separated from each other when rising up and approaching each other when descending due to the guidance of the two limiting rods  511  and the two elongated oblique holes  413 , as shown in  FIG.  9    and  FIG.  10    to achieve the purpose of grinding the blade.