Patent Publication Number: US-2023145219-A1

Title: Electric knife

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to cutting tools, especially an electric knife structure. 
     2. Description of the Related Art 
     In order to increase the effect of the cutting tool in use, there are many electric cutting tools on the market, and most of this type of cutting tools are structured by directly connecting the cutter blade to a driving device such as a motor or a vibration unit. Although this structure can provide the direct driving force of the cutter blade, it is easy to cause the output end of the driving device to be twisted and deformed or even damaged when the cutter blade is pressed. This problem should 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 that is stable in structure, easy to maintain, and can protect the driving device from damage. 
     In order to achieve the above object, the electric knife of the present invention comprises: a cutter blade and a handle, and the handle is internally equipped with a drive unit and a driven unit. The cutter blade is located in the driven unit. The drive unit and the driven unit are connected through a link, so that the drive unit can drive the cutter blade of the driven unit to reciprocate along an axis. 
     According to the electric knife of the present invention with the above structure, because the drive unit and the driven unit are pivotally connected by a link, when the cutter blade on the driven unit is under pressure, the compressed pressure or twisted force can be absorbed by the link, and will not be directly transmitted to the output shaft of the motor and cause damage to the output shaft. 
     Preferably, the drive unit comprises a first movable sleeve, the driven unit comprises a second movable sleeve, and the first movable sleeve and the second movable sleeve are connected with the link. 
     Preferably, the drive unit comprises a screw with two threads in opposite directions. 
     Preferably, the drive unit further comprises two rolling members, which are respectively set on one side of the two threads of the screw. The two rolling members can scroll along the corresponding threads. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is a three-dimensional schematic diagram of the appearance of the present invention. 
         FIG.  2    is an exploded view of the present invention. 
         FIG.  3    is an exploded view of the drive unit of the present invention. 
         FIG.  4    is an exploded view of the driven unit of the present invention. 
         FIG.  5    is a sectional view taken along line  5 - 5  of  FIG.  1   . 
         FIG.  6    is a sectional view taken along line  6 - 6  of  FIG.  1   . 
         FIG.  7    is the same as  FIG.  6   , which is a schematic cross-sectional view of another embodiment of the screw and the first fixed sleeve in the creation. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The applicant first explains here that throughout the specification, including the embodiments described below and the claims in the scope of the patent application, the nouns related to directionality are based on the directions in the drawings. Secondly, in the embodiments and drawings that will be introduced below, the same element numbers represent the same or similar elements or their structural features. 
     Referring to  FIG.  1    to  FIG.  6   , the electric knife of the present invention comprises: a handle  1 , a cutter blade  2 , a switch  3  set on the handle  1 , and a power supply  4 , a drive unit  10  and a driven unit  20  mounted inside the handle  1 . The cutter blade  2  is located in the driven unit  20 . In this embodiment, the power supply  4  is a battery, but the power supply can also be a wire directly connected to external power. 
     The drive unit  10  comprises a motor  110 , a screw  120 , a first movable sleeve  130 , a first fixed sleeve  140 , and two rolling members  150 . 
     The motor  110  is located in the handle, and one end of the motor  110  has an output shaft  111 . 
     The screw  120  is installed on the output shaft  111  of the motor and can rotate with the output shaft. The screw  120  is provided with two threads  121  in opposite directions. 
     The first movable sleeve  130  is set on the screw  120 , and each of two opposite sides of the first movable sleeve is provided with a perforation  131 . 
     The first fixed sleeve  140  is set outside the first movable sleeve  130 . One end of the first fixed sleeve  140  is combined and fixed with the motor  110 . The two sides of the first fixed sleeve  140  are provided with two long guide grooves  141  corresponding to the second perforations  131  of the first movable sleeve. The long axis of the guide grooves  141  is in the same direction as the axis of the motor output shaft  111 . 
     The two rolling members  150  are respectively set on one side of the two threads  121  of the screw, and the two rolling members  150  can roll along the corresponding threads  121 . In this embodiment, the two rolling members  150  are two balls, but it is not limited to this. One side of the two rolling members  150  is attached to the threads  121  of the screw, and the other side protrudes out of the first movable sleeve  130  through the perforations  131  of the first movable sleeve. The protruding part of the two rolling members  150  will be limited in the guide grooves  141  of the first fixed sleeve. 
     The driven unit  20  comprises a cutter blade holder  210 , a second movable sleeve  220 , and a second fixed sleeve  230 . 
     One end of the cutter blade  2  is fixed to the cutter blade holder  210 . 
     The second movable sleeve  220  is set on the cutter blade holder  210  and is fixed in combination with the cutter blade holder  210 . 
     The second fixed sleeve  230  is set outside the second movable sleeve  220  and fixed in the handle  1 . 
     The drive unit  10  and the driven unit  20  are pivotally connected by a link  30 , so that the second movable sleeve  220  of the driven unit can be driven by the first movable sleeve  130  of the drive unit. In this embodiment, one end of the first movable sleeve  130  of the drive unit  10  is provided with a pivot hole  132 , and one end of the second movable sleeve  220  is also provided with a pivot hole  221 , and the link  30  is respectively pivotally connected to the pivot hole  132  of the first movable sleeve and the pivot hole  221  of the second movable sleeve. Through this structure, the first movable sleeve  130  and the second movable sleeve  220  can be interlocked but can maintain the respective travel space of the first movable sleeve  130  and the second movable sleeve  220 . In other words, the second movable sleeve  220  will not have a direct impact on the first movable sleeve  130  if it produces up, down, left, and right deflection. 
     With the structure of the present invention, the operation method is the same as that of general cutting tools. The user holds handle  1  and turns on the switch  3 , and the output shaft  111  of the motor  110  will rotate and drive the screw  120  to rotate. The rotation of screw  120  will move the two rolling members  150  and push the first movable sleeve  130  to move. However, because the movable range of the two rolling members  150  is limited to the corresponding guide grooves  141 , the first movable sleeve  130  can only move back and forth along one axis, which is the same axis as the output shaft  111  of the motor. The first movable sleeve  130  will be linked with the second movable sleeve  220  through the link  30 , which will then drive the second movable sleeve  220  to move back and forth. The cutter blade holder  210  that fixes the cutter blade  2  is fixed to the second movable sleeve  220 , so it will also move with the second movable sleeve  220 , thereby achieving the function of reciprocating the cutter blade  2 . 
     The advantages of the present invention are: Because the drive unit  10  and the driven unit  20  are pivotally connected by the link  30 , when the cutter blade on the driven unit  20  is under pressure, the compressed pressure or twisted force can be absorbed by the link  30 , and it will not be directly transmitted to the output shaft  111  of the motor and cause damage to the output shaft. 
     In addition, because the drive unit and the driven unit are separated in the present invention, each unit does not need to be disassembled and replaced during maintenance, and the maintenance is easier. 
     In addition, it should be noted that in the above embodiment, two rolling members  150  and two threads  121  are provided on the screw  120 , but one rolling member  150  and one thread  121  can also be used, as shown in  FIG.  7   . Using two rolling members and two threads can have a better balance, but using one rolling member and one thread can also make the first movable sleeve move back and forth. 
     In addition, in this embodiment, the cutter blade holder  210  and the second movable sleeve  220  are separated into two components because of the convenience of assembly. The cutter blade holder  210  and the second movable sleeve  220  can also be combined into a single component, that is, the cutter blade  2  can be directly fixed to the second movable sleeve  220 . The second fixed sleeve  230  can also be combined with the handle  1  to become a part of the handle  1 . Similarly, the first fixed sleeve can also be combined with the handle to become one.