Abstract:
A vegetable and fruit cutting device having a rack; a slide-rail adapted for moving vertically mounted on the rack; a platform mounted on the slide-rail; a serrated-blade assembly; a flat-blade assembly; and an escalating device adapted for adjusting vertical movement of the platform. The escalating device having an eccentric cam assembly mounted below the platform and a knob adapted for driving the eccentric cam assembly mounted to the side of the body. The eccentric cam assembly having a shaft mounted between the top of the rack and the bottom of the platform, the shaft having an eccentric cam which is fixed to the shaft. The serrated-blade assembly is mounted to the bottom of the platform. And the platform has a second aperture for receiving a serrated-blade of the serrated-blade assembly.

Description:
CROSS REFERENCE TO RELATED PATENT APPLICATION 
     The present application claims the priority of Chinese patent application No. 200920296852.4 filed on Dec. 31, 2009, which application is incorporated herein by reference. 
     BACKGROUND OF TH INVENTION 
     1. Field of the Invention 
     The present invention relates to a vegetable and fruit processing device, and more particularly to a vegetable and fruit cutting device with a platform which can be adjustable. 
     2. Description of the Related Art 
     Vegetable and fruit cutting device is mainly a device having vertical blades and horizontal blades. When vegetable or fruit passes through the device, blades thereof may cut vegetables or fruits into strips or slices. 
     The common vegetable and fruit cutting device in the market is generally classified into two types. One type of the device is connecting a handle with a row of balanced blades, it exerts force downwardly from the top end of the vegetable or the fruit, and the vegetable or the fruit will be cut into slices by the blades. Then the device rotates about 90 degrees to the left or the right, and by repeating the above cutting process, the vegetable or the fruit will then be cut into strips. However, this type of device has two disadvantages. One is that the user is required to perform repeated actions of vertical cutting process to cut the vegetable or the fruit into strips, the other is that the user is not able to control the thickness of finished products. 
     Another type of the device comprises a slide-rail, a serrated-blade assembly and a flat-blade assembly disposed on the slide-rail. This device has a slide-rail that may move up or down in order to adjust the height thereof, thus the thicknesses of the slices or the strips of the vegetable or the fruit can be controlled by adjusting the height of the slide-rail. However, based on the existing technology, the above structure of the slide-rail is complicated and the manufacturing cost is comparatively high. Furthermore, it is easy to be blocked and therefore it is also unreliable in using. 
     SUMMARY OF THE INVENTION 
     The present invention relates to a vegetable and fruit cutting device which is reliable in use and has a simple structure to solve the problem of the high manufacturing cost and being unreliable in use of the conventional vegetable and fruit cutting device. 
     A vegetable and fruit cutting device in accordance with an exemplary embodiment of the present invention, comprises: 
     a rack; 
     a slide-rail mounted on the rack and adapted for moving vertically; 
     a platform mounted on the slide-rail; 
     a serrated-blade assembly; 
     a flat-blade assembly; and 
     an escalating device adapted for adjusting the vertical movement of the platform; 
     wherein the escalating device includes an eccentric cam assembly mounted below the platform, and a knob mounted on one side of the rack that adapted for driving the eccentric cam assembly, an active aperture is positioned below the platform for the lifting of the platform; the eccentric cam assembly includes a controlling shaft under the platform and rotatably mounted on the rack, an eccentric cam fixed on the controlling shaft and matching with the active aperture; the serrated-blade assembly is rotatably set under the platform, and a blade aperture for receiving the serrated-blade of the serrated-blade assembly is provided on the platform. 
     Typically, in the vegetable and fruit cutting device, two opposite active apertures are positioned below the platform, and the controlling shaft has two eccentric cams that corresponding to the two opposite active apertures. 
     Typically, in the vegetable and fruit cutting device, the escalating device includes two sets of eccentric cam assembly, a synchronizer is provided between the two sets of eccentric cam assembly, and the synchronizer has two synchronized gears disposed at a same end of two controlling shafts of the two eccentric cam assemblies, and a gear rack engaged with the two synchronized gears is provided on the rack. 
     Typically, in the vegetable and fruit cutting device, a position device is mounted between the knob and the controlling shaft, the positioning device includes a driven gear mounted on a side of an end face of the knob, a fixed gear mounted on the rack, a first spring sleeved on an end of the controlling shaft which is projecting from the rack, and a first fixed bolt for securing the first spring between the knob and the end of the controlling shaft. 
     Typically, in the vegetable and fruit cutting device, the serrated-blade assembly includes a blade device rotatably provided on the rack, and a blade knob provided on an end of the blade device for controlling the rotation of the blade device. 
     Typically, in the vegetable and fruit cutting device, the blade device includes a blade connecting shaft rotatably set on the rack and one end of the connecting shaft which is projecting from a side of the rack, and a blade assembly provided on the blade connecting shaft; the blade knob is sleeved on an end of the connecting shaft which is projecting from the rack. 
     Typically, in the vegetable and fruit cutting device, an axial installing slot is provided on a side of the blade connecting shaft, the blade assembly includes a serrated-blade base that matching with the axial installing slot, and a plurality of serrated-blades radially provided on one side of the serrated-blade base along the blade connecting shaft; the serrated-blade is matching with the second aperture of the platform. 
     Typically, in the vegetable and fruit cutting device, at least two sets of blade assembly are provided on the blade connecting shaft, and a blade-replacing positioning device is provided between the blade knob and the rack, the blade-replacing positioning device is adapted for securing the blade connecting shaft so that one set of the blade assembly is passing through the blade aperture to extend to the upside of the platform. 
     Typically, in the vegetable and fruit cutting device, the blade connecting shaft is rotatably mounted on the rack through a shaft aperture, the blade-replacing positioning device includes a positioning convex provided on a side of end face of the blade knob that corresponding to the position that blade assembly mounted on the blade connecting shaft, at least one positioning slot that matching with the positioning convex is provided around the shaft aperture, a second spring sleeved on an end of the blade connecting shaft which is projecting from the rack, and a second fixed bolt for securing the second spring between the blade knob and the end of the connecting shaft. 
     Typically, in the vegetable and fruit cutting device, the rack includes a body and a foot assembly that rotatably mounted on the bottom of the back-end of the body, at least one foot support is provided on the bottom of the back-end of the body; the foot assembly includes a foot body and a locking device for rotatably connecting the foot body with the foot support. 
     Typically, in the vegetable and fruit cutting device, two foot shaft apertures are symmetrically set on the foot support, and two foot locking holes are set on the foot body that corresponding with the two foot shaft apertures, one set of the locking device is provided related to the foot shaft aperture and foot locking hole; the locking device includes a cylinder, an elongated foot lock adapted to pass through the foot shaft aperture and foot locking hole, and a foot locking cover fastened on the elongated foot lock. 
     Typically, in the vegetable and fruit cutting device, a foot positioning device for securing the foot assembly with predetermined angle is provided between the foot assembly and the rack, the foot positioning device includes an elastic bulge and a retaining nest that provided between the cylinder and the side walls of the foot shaft aperture and the foot locking hole. 
     Typically, in the vegetable and fruit cutting device, a concave member adapted for receiving the opening of a container for storing the cut vegetable or fruit is positioned below the rack body and the foot body. 
     Typically, in the vegetable and fruit cutting device, a cover for protecting the serrated-blade assembly is rotatably set on the bottom of the rack and under the serrated-blade assembly. 
     The vegetable and fruit cutting device of the present invention has the following advantages. Since the rack includes the eccentric cam assembly and the knob, and the eccentric cam assembly comprises the controlling shaft rotatably disposed under the moveable platform of the rack, the knob rotates to drive the controlling shaft to rotate, thus the platform moves up or down to adjust the location of the platform relative to the serrated-blade assembly for controlling the thickness of the cut vegetable or the cut fruit. Since the present invention moves up or down the platform by the rotation of the eccentric cam assembly, the whole structure is simple, and the manufacturing cost is low. At this moment, since the location of the platform is mainly relative to the relative location of the eccentric cam in the platform active hole, and the eccentric cam is not blocked in the active hole, the whole device is reliable in use and can undertake a large pressure, thus the whole device has a long lifetime. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       These and other features and advantages of the various embodiments disclosed herein will be better understood with respect to the following description and drawings, in which like numbers refer to like parts throughout, and in which: 
         FIG. 1  is an exploded schematic view of a vegetable and fruit cutting device according to a preferred embodiment of the present invention. 
         FIG. 2  is an exploded schematic view of a rack of a vegetable and fruit cutting device according to a preferred embodiment of the present invention. 
         FIG. 2   a  is a partial-enlarged schematic view of I as shown in  FIG. 2 . 
         FIG. 3  is a structure schematic view of a rack of a vegetable and fruit cutting device according to a preferred embodiment of the present invention. 
         FIG. 4  is a structure schematic view of an escalating device of a vegetable and fruit cutting device according to a preferred embodiment of the present invention. 
         FIG. 4   a  is a structure schematic view of a side cover of a vegetable and fruit cutting device according to a preferred embodiment of the present invention. 
         FIG. 5  is a structure schematic view of a moveable board of a vegetable and fruit cutting device according to a preferred embodiment of the present invention. 
         FIG. 6  is an exploded schematic view of a rotating blade assembly of a vegetable and fruit cutting device according to a preferred embodiment of the present invention. 
         FIG. 7  is a structure schematic view of the rotating blade assembly of a vegetable and fruit cutting device according to a preferred embodiment of the present invention. 
         FIG. 8  is a structure schematic view of a flat-blade assembly of a vegetable and fruit cutting device according to a preferred embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Reference will now be made to the drawings to describe exemplary embodiments of the present vegetable and fruit cutting device in detail. The following description is given by way of example, and not limitation. 
     As shown in  FIG. 1 , a vegetable and fruit cutting device in accordance with an exemplary embodiment of the pressing invention, comprises a rack  100 , a slide-rail  200  on the rack  100 , a serrated-blade assembly  300  and a flat-blade assembly  400 . When the vegetable or the fruit slides along the slide-rail  200 , the serrated-blade assembly  300  and the flat-blade assembly  400  will cut the vegetable or the fruit into strips. When the flat-blade assembly  400  is only used, the vegetable or the fruit will be cut into slices. 
     As shown in  FIGS. 1 ,  2 ,  2   a  and  3 , the rack  100  comprises a body  110  and a foot assembly  120  arranged at the bottom of the body  110 . Typically, the body  110  has a foot support  111  arranged at the bottom thereof, which is configured for connecting rotatably with the foot assembly  120 . The foot assembly  120  comprises a foot body  121 , two foot locks  122  and two foot locking covers  123 . The foot body  121  is typically set as an H-shape support, and the central horizontal portion thereof is a foot handle  124  for being held conveniently to rotate the whole foot assembly  120 . Typically, an antiskid pad  102  is arranged at the bottom of the foot body such that the whole rack is not easy to slide when it is placed on the working platform. The foot support  111  has two foot shaft apertures  125  arranged symmetrically thereon, and the foot body  121  has two foot locking holes  126  arranged thereon which correspond to the foot shaft apertures  125 . A projecting cylinder  127  is arranged on the foot locks  122 . The projecting cylinder  127  passes through the foot shaft apertures  125  and the foot locking holes  126  to interference fit with the foot locking covers  123 , such that the foot body  121  is rotatably connected with the foot support  111 . If pulling the foot handle  124 , a torque is produced on the foot body  121  to adjust the inclined angle of the foot body  121  relative to the body  110 , such that the inclined angle of the slide-rail  200  on the body  110  is adjustable. Thus it is convenient for the user to choose the force-direction which is suitable for the user when he holds the vegetable or the fruit slides on the slide-rail  200 . When the foot body  121  rotates to the horizontal, the shape of the foot body  121  flushes the bottom of the body  110 . 
     Typically, a support positioning device is arranged between the foot assembly  120  and the rack  100  to position the foot assembly  120  at a predetermined angle relative to the rack  100 . In detail, the foot positioning device comprises an elastic positioning convex  131  arranged on the cylindrical surface of the projecting cylinder  127 , positioning slots  132 ,  133  arranged in the corresponding locations of the foot shaft apertures  125  and the foot locking holes  126 . At least two positioning slots  133   a  and  133   b  are arranged in the hole wall of the foot locking holes  126 , a positioning slot  132  is arranged in the hole wall of the foot shaft apertures  125 , and the diameter of the foot locking holes  126  is larger than the that of the foot shaft apertures  125 . A flexible piece  134  is arranged on the cylindrical surface of the projecting cylinder  127  of the foot locks  122 , and the elastic positioning convex  131  is arranged on the flexible piece  134 . When the projecting cylinder  127  of the foot locks  122  is inserted into the foot locking holes  126  and the foot shaft apertures  125 , the positioning slot  132  of the elastic positioning convex  131  and the foot shaft apertures  125  fits with the positioning slot  133   a  of the foot locking holes  126 . At this moment, the foot body  121  is retracted into the bottom of the rack  100 . That is, it is parallel to the bottom of the rack  100 . When holding the foot handle  124  of the foot body  121  and pulling the foot body  121 , the foot body  121  rotates around the axis of the foot shaft holes  125 . At this moment, the hole wall of the foot locking holes  126  pulls the elastic positioning convex  131  of the foot locks  122  out of the positioning slot  133   a  of the foot locking holes  126  to the hole wall of the foot locking holes  126 . Since the diameter of the foot locking holes  126  is larger than that of the foot shaft apertures  125 , the elastic positioning convex  131  is still cooperated with the positioning slot  132  of the foot shaft apertures  125  at this moment. That is, the foot locks  122  are unmoved relative to the foot shaft apertures  125  and rotate relative to the foot body  121 . When the another positioning slot  133   b  in the hole wall of the foot locking holes  126  rotates to a same straight line with the positioning slot  132  in the hole wall of the foot shaft apertures  125 , the another positioning slot  133   b  in the hole wall of the foot locking holes  126  is cooperated with the elastic positioning convex  131  such that the whole foot body  121  is positioned at another location. A plurality of positioning slots may be arranged in the hole wall of the foot locking holes  126  in actual need, such that the foot body  121  may be positioned at a plurality of different locations. 
     In the preferred embodiment of the present invention, the body  110  is a frame structure, and comprises a left side-plate  112  and a right side-plate  113  arranged at the left and right sides thereof respectively. The left side-plate  112  and the right side-plate  113  are connected through a transom  114 . The slide-rail  200  is arranged between the left side-plate  112  and the right side-plate  113  and on the transom  114 . A platform  210  is arranged upon the slide-rail  200  and between the left side-plate  112  and the right side-plate  113 . An escalating device  500  is arranged under the platform  210  to control the action of up or down of the platform  210 . A switch slot  118  is arranged in the right side-plate  113 , and a side cover  115  is arranged on the side of the switch slot  118  for shielding the switch slot  118 . 
     As shown in  FIGS. 1 ,  4 ,  4   a  and  5 , the escalating device  500  comprises an eccentric cam assembly  510  and a knob  520 . In a preferable exemplary embodiment, the escalating device  500  may comprises two eccentric cam assemblies  510 , and the two eccentric cam assemblies  510  rotate synchronously by a synchronizer  530 . Thus the user may rotate the knob  520  to rotate the eccentric cam assemblies  510 , such that the platform  210  moves up or down. In detail, the platform  210  extends downward and comprises left and right block-plates  211 ,  212  extending therefrom. The left and right block-plates  211 ,  212  have platform active holes  213  formed therein. Each of the eccentric cam assemblies  510  has a controlling shaft  511 , and the controlling shaft  511  has eccentric cams  512  fixed thereon and cooperated with the two platform active holes  213  of the platform  210 . Typically, the eccentric cams are integrated with the platform control shaft, and the peak of the major axis of the eccentric cams is same to the circumference position of the platform controlling axis. The rack  100  has a shaft-hole  116 , such that the platform controlling axis may be arranged rotatably in the rack  100 . One terminal of one of the platform controlling axis passes through the rack  100  and the shaft-holes  116   a ,  116   b ,  116   c  arranged in the side cover  115  extend out of the rack  100  and cooperate with the knob  520 . That is, the knob  520  is fixed on the extending terminal of the platform control axis. When the knob  520  drives the platform controlling axis to rotate, the eccentric cams  512  of the platform controlling axis rotate in the platform active holes  213 , to move up or down the platform  210 . Since the two eccentric cams cooperated with each other and the platform active holes  213  are arranged between the platform  210  and the platform controlling axis, and are arranged at the left and right sides respectively, the platform  210  will not be inclined when the platform  210  moves up or down. 
     As shown in  FIGS. 4 and 4   a , the synchronizer  530  comprises synchronized gears  531   a ,  531   b  arranged at the same terminal of the two platform controlling shaft, and a rack  532  arranged slideably in the switch slot  118 . The rack  532  engages with the two synchronized gears  531   a ,  531   b , and the two synchronized gears  531   a ,  531   b  are arranged at the terminal of the corresponding platform controlling shaft and rotate synchronously with the platform controlling shaft  511   a ,  511   b . The knob  520  cooperates with one of the platform controlling shaft. When the knob  520  drives the platform controlling shaft  511   a  to rotate, the synchronization gear  531   a  of the platform controlling shaft  511   a  drives the rack  532  to slide, and the rack  532  drives the other synchronization gear  531   b  to rotate. Then another platform controlling shaft  511   b  is driven to rotate, thus the two eccentric cam assemblies  510   a  and  510   b  rotate synchronously. The two eccentric cam assemblies  510  are disposed at the front and back locations below the platform  210  respectively. Typically, the angle locations of the peaks of the major axis of the eccentric cams  512   a  and  512   b  are same, to ensure moving up or down the front and back portions of the platform  210  consistently. Since the eccentric cam assemblies  510  are disposed at the front and back portions under the platform  210 , such that the front and back portions of the whole platform can move up or down synchronously during the up-down moving process. Furthermore, it also can disperse the pressures of the platform  210  relative to the eccentric cam assemblies  510 , reduce the attrition, and ensure the location precision of the platform  210  relative to the serrated-blade assembly  300 . 
     For preventing the platform  210  from moving down automatically during the using process, typically, a positioning device  540  is disposed between the knob  520  and the eccentric cam assembly  510 . The positioning device  540  is mainly performed by a contrite gear group which elastically engages. The positioning device  540  comprises a driven gear  541 , a fixed gear  542 , a first spring  543  and a first fixed bolt  544 . An extending terminal is arranged at the platform controlling shaft  511  out of the rack  100  and is cooperated with the shaft-hole  116   c  of the side cover  115 . Typically, the fixed gear  542  is disposed at a side of the shaft-hole  116   c  toward the rack  100 , and the driven gear  541  is disposed at an end face of the knob  520  adjacent to an end of the rack  100 . A spring seat  545  is disposed at another terminal of the knob. The first fixed bolt  544  is disposed at the extending terminal of the platform controlling shaft  511   a , and the first spring  543  is set at the end of the platform controlling shaft  511   a  and disposed between the spring seat  545  of the knob and the first fixed bolt  544 . When the knob  520  rotates, the driven gear  541  of the knob and the fixed gear  542  of the side cover break from engaging, and the tooth crests of the contrite gear group contact, to push the knob  520  to move a little in a direction far away from the rack  100 . After rotating a certain angle, the driven gear  541  and the fixed gear  542  engage with each other again, and the knob  520  resets by the spring action of the first spring  543 . Thus the driven gear  541  attaches the fixed gear  542 , to position the platform controlling shaft  511   a  at a new rotation position. The present invention can position the platform controlling shaft  511   a  at different rotation positions, thus the platform  210  can be positioned at different horizontal heights and will not alter the distance from the rack  100  by the pressure of cutting the vegetable or the fruit. Therefore, it can ensure the correct position of the platform  210  relative to the serrated-blade assembly  300  and the consistency of cut vegetable or fruit. 
     As shown in  FIGS. 5 ,  6 , and  7 , the serrated-blade assembly  300  is disposed rotatably below the platform  210 , and blade aperture  214  is disposed on the platform  210  such that the serrated-blades  332  of the serrated-blade assembly  300  can pass through the blade aperture  214  above the platform  210 , that is reaching the slide-rail  200 . When the vegetable or the fruit slides the blade aperture  214  along the platform  210 , the serrated-blades  332  of the serrated-blade assembly  300  can cut the vegetable or the fruit with the equal space, and cooperate the flat-blade assembly  400  to cut vegetable or fruit into strips. In detail, the serrated-blade assembly  300  comprises a blade device  320  arranged rotatably on the rack  100  and under the platform  210 , and a blade knob  310  for driving the blade device  320  to rotate. The blade device  320  comprises a blade connecting shaft  321  and a blade assembly  330 . The rack  100  has blade connecting shaft-holes  117  for disposing rotatably the blade connecting shaft  321  on the rack  100 . An end of the blade connecting shaft  321  passes through the blade connecting shaft-holes  117   a ,  117   b ,  117   c  arranged on the rack  100  and the side cover  115 , and extends out of a side of the rack  100 . The blade knob  310  is fixedly set on the extending end of the blade connecting shaft  321 . It can rotate the blade knob  310  at the side of the rack to rotate the blade connecting shaft  321  for driving the blade assembly  330  arranged on the blade connecting shaft to rotate, such that the serrated-blades  332  of the blade assembly stick out of the blade aperture  214  of the platform, or take back from the blade aperture  214  to the platform. 
     Typically, the blade assembly  330  comprises a serrated-blade sheath  336 , a serrated-blade base  331  and a plurality of serrated-blades  332  fixed at a same side of the serrated-blade base  331 . Each of the serrated-blades  332  is perpendicularly fixed on a side of the serrated-blade base  331 . Typically, every two adjacent serrated-blades have a same distance therebetween, to cut the vegetable or the fruit into uniform strips. The serrated-blade sheath  336  has a plurality of through holes  337  therein which match the serrated-blades for being passed through by the serrated blade  332 . The serrated-blade base  331  is embedded in the bottom of the serrated-blade sheath  336 , and the side of the serrated-blade base  331  having the serrated-blades  332  is adjacent to the serrated-blade sheath  336 , such that the serrated-blades  332  are disposed between the serrated-blade sheath  336  and the serrated-blade base  331 . Therefore, the serrated-blades  332  are fixed firmly and can be replaced according to the need. An installation slot  333  is disposed in a side of the blade connecting shaft  321  along the axis. The shape of the serrated-blade sheath  336  matches the installation slot  333 . The serrated-blade sheath  336  can pass through the end surface of the blade connecting shaft  321  to insert the installation slot  333 , such that the serrated-blade base  331  is fixed on the side of the blade connecting shaft  321 . In detail, it is better to set a sleeve  334  in the outside of the blade connecting shaft  321 , and a central axis-hole  335  is disposed in the center of the sleeve  334  and matches the blade connecting shaft  321 . The central axis-hole  335  is polygon or irregular-shape that matches the sectional shape of the blade connecting shaft  321 , such that the sleeve  334  can rotate synchronously with the blade connecting shaft  321 . The installation slot  333  is disposed in the side of the sleeve  334 , to dispose the blade assembly  330  on the sleeve  334 , for easily processing the installation slot  333 . In an alternative exemplary embodiment, the installation slot  333  still can be directly disposed in the side of the blade connecting shaft  321 . In a preferable exemplary embodiment, the blade device  320  has a plurality of blade assemblies  330  disposed thereon, and the serrated-blades  332  of each of the blade assemblies have different heights. In detail, a plurality of installation slots  333  matching the amount of the blade assemblies  330  are disposed in the side of the sleeve  334 , thus the blade assemblies  330  can be inserted into the installation slots  333  respectively. Typically, the plurality of installation slots  333  are disposed circumference uniformly in the side of the sleeve  334 . When rotating the blade knob  310  to rotate the blade connecting shaft  321 , it can select one of the blade assemblies  330  having the serrated-blades with the different height to pass through the blade aperture  214  of the platform, for cutting the vegetable or the fruit sliding on the slide-rail  200  with different depths, and then cooperating the flat-blade assembly  400  to cut the vegetable or the fruit with different thicknesses. 
     For positioning the different blade assemblies  330  in the blade aperture  214  of the platform, a changing-blade and positioning mechanism  340  is typically disposed between the rack  100  and the blade knob  310 . The blade connecting shaft  321  passes through the blade connecting shaft-holes  117  disposed in the side cover  115  of the side of the rack  100  and extends out of the rack  100 . The changing-blade and positioning mechanism  340  comprises a second spring  341 , a second screw  342 , a positioning slot  343  disposed in the side cover  115 , and positioning convex  344  disposed on the blade knob  310 , and the positioning convex  344  may cooperate with the positioning slots  343 . Typically, a connecting hole  345  is disposed in the blade knob  310  and cooperates with the extending end of the blade connecting shaft  321 . The extending end of the blade connecting shaft  321  is polygon, and the connecting hole  345  of the blade knob  310  matches the shape of the extending end of the blade connecting shaft  321 , thus the blade knob  310  can be fixed at the end of the blade connecting shaft  321  and can be limited to rotate circumferentially relative to the blade connecting shaft  321 . The positioning convex  344  are disposed on the end of the blade knob  310  adjacent to the rack, and a spring seat  346  is disposed on another end thereof. The amount of the positioning convex  344  are equal to that of the blade assemblies, and the circumferential locations of the positioning convex on the blade knob  310  and the locations of the installation slots  333  of the blade connecting shaft  321  are arranged at a same straight line. The positioning slots  343  are disposed around the blade connecting shaft-holes  117  of the side cover  115 , and match the positioning convex  344 . The second screw  342  is disposed on the extending end of the blade connecting shaft  321 , and the second spring  341  is set on the end of the blade connecting shaft  321  and between the spring seat  346  and the second screw  342  of the blade knob  310 . In use, the blade knob  310  is pulled out in the horizontal direction from the side of the rack  100 , to make the positioning convex  344  break away from the positioning slot  343 . Then the blade knob  310  rotates until the positioning convex  344  cooperates with another positioning slot  343 . The blade knob  310  compresses tightly on the side cover  115  by the elastic force of the second spring  341 . At this moment, the blade connecting shaft  321  cannot continuous to rotate, and the corresponding blade device assembly  320  sticks out of the blade hole  214 , to reliably position the serrated-blade assembly  300 . 
     Typically, the serrated-blade assembly  300  has a blade assembly  330   c  without the serrated-blades  332 . That is, the blade assembly  330   c  only has the serrated-blade sheath  336  and does not have the serrated-blades and the serrated-blade base. When the blade assembly  330   c  is corresponding to the blade aperture  214  of the platform  210 , that is, the blade assembly  330   c  reaches under the blade aperture  214 , no serrated-blade is on the platform  210 , and the vegetable or the fruit will not be cut and directly slide to the flat-blade assembly  400  when it slides on the slide-rail  200 , to produce the slices of the cut vegetable or fruit. 
     According to the above description, the serrated-blades  332  of the blade assembly  330  are exposed under the bottom of the rack  100 . For protecting the serrated-blades  332  from damaging and preventing the serrated-blades  332  from hurting hand during the process of transportation and use, a protection cover or cover  101  is typically disposed on the bottom of the rack  100 . The protection cover or cover  101  is rotatably disposed on the rack  100  and under the serrated-blade assembly  300 , to cover the whole serrated-blade assembly  300 . 
     As shown in  FIGS. 1 and 8 , the flat-blade assembly  400  is disposed at the front end of the slide-rail  200  of the rack  100 . The flat-blade assembly  400  comprises a flat-blade board  410  and a flat blade  420 . The flat blade  420  is fixed at a side of the cutter point  411  of the flat blade  420  by the fastener, such as the screw  401  etc. The cutter point  411  of the flat-blade board is a side edge of the flat-blade board  410  adjacent to the back end of the rack  100 . The flat blade  420  is typically V-shape, and the cutter point  411  of the flat-blade board is also V-shape corresponding to the shape of the flat blade  420 . The flat-blade board  410  is disposed in the slide-rail  200  of the rack  100 , thus the vegetable or the fruit are cut horizontally when it passes through the flat-blade assembly  400 . 
     As shown in  FIGS. 1 and 2 , in a preferable exemplary embodiment, concave members  103   a  and  103   b  are disposed at the bottom of the body and the foot body. When the whole vegetable and fruit cutting device is placed on the opening of the container configured for collecting the cut vegetable or fruit, the concave members are corresponding to the opening of the container such that the whole rack can be blocked at the opening of the container for reliably positioning. Typically, the concave member  103   a  of the body and the concave member  103   b  of the foot body are disposed at the two side of the cutter point  411  of the flat-blade board respectively, such that the cut vegetable or fruit fall into the container. 
     The above described implementation example only demonstrates several implementation methods of this practical new type. The description is concrete and detailed. But it should not be understood as the limit of the patent scope of this practical new type. It should point out that for the common technicians of this field, they can make several changes and improvements on the condition that the conception and design of this practical new type is followed.