Patent Publication Number: US-2022225830-A1

Title: Chopper blade assembly

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is related to co-pending attorney reference number 132090-D200, which is incorporated by reference herein. 
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH 
     Not applicable. 
     BACKGROUND OF THE INVENTION 
     The present invention relates in general to household food choppers. 
     It is well known to provide food choppers for home use. These choppers are distinct from blenders, in that the food is cut into relatively small pieces rather than rendered into a puree or viscous liquid. While electric versions are available, it is also well known for these choppers to be operated manually as by a crank as in USD530995, or manually as by a pull cord as in USD614457,both to the current applicant. These choppers are typically used to chop tomatoes, onions, carrots, and the like into smaller pieces, such as for salsa. 
     SUMMARY OF THE INVENTION 
     An object of the present invention is to provide a food chopper having improved chopping. 
     Another object of the present invention is to provide a food chopper with an improved blade column providing improved chopping. 
     A further object of the present invention is to provide a food chopper blade column where the upper blades tend to force the food downward toward additional cutting blades. 
     These and other objects are achieved by a food chopper blade column. The column will be rotated in a cutting direction within the chopper during use, and mounts a plurality of cantilevered blades spaced circumferentially about the column. The upper blades include a leading edge having a single bevel cutting edge on their lower face, as well as trailing edge which is angled downward. The lowermost blade includes a leading edge having a single bevel cutting edge on its upper face, and a flat trailing edge. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The objects and features of the invention noted above are explained in more detail with reference to the drawings, in which like reference numerals denote like elements, and in which: 
         FIG. 1  is a top perspective view of a food chopper employing a blade column according to the present invention in the operative configuration; 
         FIG. 2  is an exploded top perspective view of the food chopper of  FIG. 1 ; 
         FIG. 3  is a side cross-sectional view along line 3-3 of  FIG. 1 ; 
         FIG. 4  is a top perspective view of a blade column as in  FIG. 2 ; 
         FIG. 5  is a top view of the blade column of  FIG. 4 ; 
         FIG. 6  is a set of detailed sectional views along lines  6   a ,  6   b , and  6   c  of  FIG. 5 , illustrating the various blade configurations side by side; and 
         FIG. 7  is an exploded view of the blade column of  FIG. 4 . 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     With reference to  FIG. 1 , a food chopper employing a blade column according to the present invention is generally designated by reference numeral  10 . The food chopper  10  generally includes a receptacle  12 , a cover  14 , a blade column  16  and a drive mechanism  18  for the blade column  16 . The receptacle  12  is in the general shape of a concave bowl with a side wall  19  leading to an upper edge  20 , and will receive the food to be chopped, as well as hold the food during chopping and after. The side wall  19  will typically be generally cylindrical or frustoconical (tapering downward) as is known in the art. The cover  14  seals to the upper edge  20  and serves to prevent the food from exiting the receptacle  12  during chopping, yet upon removal of the cover  14  allowing access to the food in the receptacle  12 . 
     The blade column  16  is received within the receptacle  12  and cover  14  for rotation in a cutting direction  21  ( FIG. 5 ) about longitudinal axis  22  ( FIG. 7 ). The blade column  16  includes at least one upper blade  24  and a single lower blade  26 , all extending radially outward from the axis  22 , and are equidistant circumferentially spaced, as best illustrated in  FIG. 5 . In the preferred embodiment shown there are two of the upper blades  24 , but different arrangements such as one, three or more upper blades  24  are possible. 
     The blade column  16  also includes a blade shaft  30  which mounts the blades  24  and  26  in fixed positions. The blade shaft  30  is rigid and elongated along the longitudinal axis  22 , with an upper end  32  and lower end  34 . The blades  24  and  26  are longitudinally spaced along the blade shaft  30 , with this spacing preferably (but not necessarily) equal. Similarly, the lower blade  26  is spaced from the lower end  34  of the blade shaft  30 , with this spacing being approximately equal to the desired final size of the chopped food. 
     The blade shaft  30  will be operatively connected to the drive mechanism  18  such that the drive mechanism  18  will cause the rotation of blade shaft  30  and blades  24  and  26  in the cutting direction  21 . Due to the forces involved, this connection will typically be gearing or other similar direct connection. In the embodiment shown, the drive mechanism  18  is a pull cord connected to a one-way drive mechanism (not shown) similar to that shown in U.S. Pat. No. 7,264,189. As such the illustrated embodiment includes an aperture in the lower end  34  of drive shaft  30  to receive a pin extending from the receptacle  12 , and the upper end  32  of shaft  30  includes a faceted drive head to be received in a mating socket (not shown) in the cover  14  which is connected to the drive mechanism  18 . Other arrangements are possible. The drive mechanism  18  could be located in the cover  14 , but be driven by a manual crank or an electric motor. While not shown, it is also known in the art for the drive mechanism  18  to be located below the receptacle  12  and connected to the blade shaft  30  via an aperture (not shown) in the bottom of the receptacle  12 . 
     The blades  24  and  26  each have a radial length which is chosen such that each blade  24  and  26  closely received within the side wall  19  of receptacle  12 . Each of the blades  24  and  26  has a generally rectangular form and includes an inner end  36 , outer end  38 , an upper face  40 , lower face  42 , and a leading edge  44  and trailing edge  46 . As shown best in  FIG. 5 , the leading edge  44  of each blade  24  and  26  is linear, but curved leading edges  44  (and trailing edges  46  if desired) are also possible. For each of the blades  24  and  26  the leading edge will be a cutting edge. 
     The arrangements described above are well known from manual and electric choppers on the market. The improvements to the blade column  16  according to the present invention will now be described. 
     A concern with prior art choppers has been the blades causing the chopped food pieces to be propelled within the receptacle  12  and then stick to the underside of cover  14  or an upper portion of side wall  19  out of the reach of the blades and thus not achieving the desired level of chopping without further manual intervention. The present invention addresses this problem. In particular, the blades  24  and  26  are formed to direct the food toward further chopping. This is achieved by the upper blade  24  directing the chopped food downward, while the lower blade  26  directs the food upward. 
     Review of  FIGS. 4  thru  6  will show that the leading edge  44  of upper blade  24  includes a single bevel on the lower face  42 , while the leading edge  44  of lower blade  26  includes a single bevel on the upper face  40 . The bevel is believed to act as a camming surface such that food cut by the lower face  42  bevel on upper blade  24  will be urged or propelled downward; whereas the food cut by the upper face  40  bevel on the lower blade  26  will urged or propelled upward. As such, the food cut by the upper blade  24  will be directed toward the lower blade  26 , whereas the food cut by the lower blade  26  will be directed toward the upper blade  24 . To further enhance this effect, the trailing edge  46  of each of the one or more upper blades  24  includes a deflector  48  in the form of a portion of blade  24  being angled downward. As may be envisioned, and food particles which are not urged downward by the bevel on the lower face  42  will impinge upon the lower face  42  of the deflector  48  to provide a second chance to urge the food particle downward toward the other blades. 
     The present invention also includes an innovative structure for the construction of the blade column  16  which is particularly suited for the situation with the drive mechanism  18  in the cover  14 . With reference to  FIG. 7 , the column  16  includes a core  50  elongated in the direction of axis  22 . Core  50  includes an elongated drive pin  52  at the upper end, with the drive pin having a non-circular cross-section normal to axis  22 . In the embodiment shown, this cross-section takes the form of a hexagon with protrusions at each corner, but other shapes are possible. The core  50  also includes a base  54  stepped outward from the drive pin  52  so as to form a stop against sliding of components along the drive pin  52  as made more clear below. 
     Each of the upper blades  24  and the lower blade  26  include an aperture in their inner ends  36  with this aperture being shaped to fit upon drive pin  52  with the ability to slide therealong but relative rotation being prevented. As such, it may be seen that the blades  24  and  26  could be assembled to the core  50  by inserting the drive pin  52  into the aperture on the blades  24  and  26  and sliding the blades  24  and  26  into their longitudinal position. 
     Ensuring the correct longitudinal position of the blades  24  and  26  is first effected by the base  54  which acts as a stop for the lower blade  26 . The other positioning is effected by use of one or more spacers  56 . Each spacer will have an aperture to receive the drive pin  52 . While not required, it is strongly preferred to for the aperture in the spacer with a cross section to closely receive the non-circular drive pin  52  such that spacers  56  are prevented from relative rotation. A spacer  56  is placed onto the drive pin  52  above the lower blade  26 , and then the drive pin  52  is inserted into the aperture of the upper blade  24 . As may be seen, the spacer  56  will act as a stop for the upper blade  24  fixing its longitudinal position. It is also noted that the angular position of the upper blade  24  is important during this insertion to create the desired circumferential spacing of the blades  24  and  26  ( FIG. 5 ). If more than two blades are to be used, then an additional pairs of spacer  56  and upper blade  24  are assembled to the drive pin  52  as desired. In the preferred form shown with three blades, there are two spacers  56  and two upper blades  24 . 
     The blades  24  and  26  together with the spacer(s)  56  are secured in place by a pin cap  58  secured to the free end of drive pin  52  and closely abutting against the uppermost upper blade  24  to clamp all blades  24 ,  26  and all spacers  56  between the pin cap  58  and base  54 . The pin cap  58  may be secured in position by various means. Typically, the end cap  58  will include an aperture (full or blind) to receive the drive pin  52 . The connection between end cap  58  and drive pin  52  could take the form of a threaded connection; adhesive, heat; friction or ultrasonic bonding; or others. In the embodiment shown, the pin cap  58  includes a stepped aperture, the free end of the drive pin  52  includes a threaded hole, and a screw  60  extends through the aperture in the end cap  58  and into the threaded hole of the drive pin  52  to clamp the end cap  58  in place. To avoid ingress of food into the aperture of the end cap  58 , a plug  62  is press-fit into the outer end of the aperture in the end cap  58 . 
     From the foregoing it will be seen that this invention is one well adapted to attain all ends and objects set forth above together with the other advantages which are inherent within its structure. 
     It will be understood that certain features and subcombinations are of utility and may be employed without reference to other features and subcombinations. This is contemplated by and is within the scope of the claims. 
     Since many possible embodiments may be made of the invention without departing from the scope thereof, it is to be understood that all matter herein set forth of shown in the accompanying drawings is to be interpreted as illustrative, and not in a limiting sense.