Patent Abstract:
A multi-height cutting apparatus includes a fixed cutting tool means disposed around a central axis, the fixed cutting tool means having at least one cutting edge, and a plurality of rotary cutting tool means spaced between the column and the fixed cutting tool means and respectively rotated to cut can bodies being delivered one after another through a circular path between the at least one cutting edge of the fixed cutting tool means and the rotary cutting tool means, the at least one cutting edge of the fixed cutting tool means each having a stepped cutting structure, the rotary cutting tool means each having a cutting edge in a stepped structure thereof corresponding to the at least one cutting edge of the fixed cutting tool means for cutting each delivered can body at different heights.

Full Description:
BACKGROUND OF THE INVENTION 
     The present invention relates to a cutting apparatus and, more particularly, to a multi-height can body cutting apparatus that is practical to cut a can body into different heights. 
     A variety of can body cutting apparatus are commercially available. DE3619322 shows an example. However, conventional can body cutting apparatus are designed for cutting a can body into a particular height only. 
     SUMMARY OF THE INVENTION 
     The present invention has been accomplished to provide a multi-height can body cutting apparatus that is practical to cut a can body into different heights. According to one aspect of the present invention, the multi-height cutting apparatus comprises a fixed cutting tool means disposed around a central axis, the fixed cutting tool means having at least one cutting edge, and a plurality of rotary cutting tool means spaced between the column and the fixed cutting tool means and respectively rotated to cut can bodies being delivered one after another through a circular path between the at least one cutting edge of the fixed cutting tool means and the rotary cutting tool means, the at least one cutting edge of the fixed cutting tool means each having a stepped cutting structure, the rotary cutting tool means each having a cutting edge in a stepped structure thereof corresponding to the at least one cutting edge of the fixed cutting tool means for cutting each delivered can body at different heights. According to another aspect of the present invention, the multi-height cutting apparatus further comprises a shaft axially mounted in the column, and a rotary table mounted on the top side of the shaft and adapted for rotating can bodies on the rotary cutting tool means against the at least one cutting edge of the fixed cutting tool means. According to still another aspect of the present invention, one half of the outer diameter of said rotary table is greater than the shortest distance between the at least one cutting edge of the fixed cutting tool means and the longitudinal central axis minus the diameter of the can bodies. According to still another aspect of the present invention one half of the outer diameter of the rotary table is about equal to ½˜⅚ of the shortest distance between the at least one cutting edge of the fixed cutting tool means and the longitudinal central axis minus the diameter of the can bodies, or preferably equal to ⅔ of shortest distance between the at least one cutting edge of the fixed cutting tool means and the longitudinal central axis minus the diameter of the can bodies. According to still another aspect of the present invention, the rotary table has a grained peripheral face. According to still another aspect of the present invention, the fixed external cutting tool means comprises a top cutting segment, an intermediate cutting segment, and a bottom cutting segment; the rotary cutting tool means comprises a shank, a first end block and a second end block respectively provided at top and bottom ends of the shank, a barrel supported on spring means around the shank between the end blocks. According to still another aspect of the present invention, the rotary cutting tool means has barrel-like external flexible members disposed at top and bottom sides of the stepped cutting edge thereof. According to still another aspect of the present invention, the cutting edge the cutting blade of the fixed cutting tool means is corrugated and extended vertically along the length of the cutting blade. According to still another aspect of the present invention, the rotary table has a grained cylindrical peripheral face. According to still another aspect of the present invention, the rotary cutting tool means is matched with a pair of rolling barrels adapted for guiding each can body into position for cutting. According to still another aspect of the present invention, the rotary table is connected in parallel to the rotary carrier and turned about the longitudinal central axis, having a plurality of rollers arranged in pair in parallel to the longitudinal central axis at the periphery thereof and adapted for squeezing the can body on each of the rotary cutting tool means against the fixed cutting tool means. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a sectional view taken along line I—I of the cutting apparatus constructed shown in FIG.  2 . 
     FIG. 2 is a top view of a cutting apparatus constructed according to the present invention. 
     FIG. 3 illustrates the position of the rotary cutting tool relative to the external cutting tool before the entry of the workpiece (position P 1  in FIG.  2 ). 
     FIG. 4 illustrates the position of the rotary cutting tool relative to the external cutting tool upon the entry of the workpiece (position P 2  in FIG.  2 ). 
     FIG. 5 illustrates the position of the rotary cutting tool relative to the external cutting tool during cutting (position P 3  in FIG.  2 ). 
     FIG. 6 is a sectional view of a part of the smoothly arched external cutting tool according to the present invention. 
     FIG. 7 is a sectional view of a part of a cutting apparatus according to a second embodiment of the present invention. 
     FIG. 8 is a top view of a part of the cutting apparatus according to the second embodiment of the present invention. 
     FIG. 9 is a sectional view taken along line IX—IX of FIG.  8 . 
     FIG. 10 is a top view showing a fixed cutting tool with a corrugated cutting edge according to the present invention. 
     FIG. 11 is a top plain view of a part of another alternate form of the present invention. 
     FIG. 12 is a sectional view showing rollers arranged at top and bottom sides of the rotary table and pressed on the periphery of the can body against the rotary cutting tool according to the present invention. 
     FIG. 13 is a sectional view showing the elastic rotary barrel of the rotary cutting tool pressed on the peripheral wall of the can body against the butting blade of the fixed cutting tool according to the present invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring to FIGS. 1 and 2, a cutting apparatus  1  is shown comprising a machine base  2 , a column  3  vertically disposed at the center inside the machine base  2 , a rotary carrier  4  mounted around the column  3  and turned about the longitudinal central axis  5  of the column  3 , an annular gear  6  fixedly fastened to the bottom sidewall of the rotary carrier  4 , a pinion  8  meshed with the annular gear  6 , and a driving unit  7  adapted to rotate the pinion  8 . The rotary carrier  4  comprises a plurality of vertical guide holes  9  equiangularly spaced from one another and disposed in parallel to the longitudinal central axis  5  of the column  3 . Axles  10  are respectively slidably mounted in the vertical guide holes  9 , each having a peripheral wedge block  13  inserted into a vertical guide groove  14  in the corresponding vertical guide hole  9 . Rollers  11  are respectively coupled to the axles  10  below the rotary carrier  4  and coupled to a peripheral groove  12  in the bottom flange of the column  3 . Four rotary cutting tools  15  are provided above the axles  10 . The rotary cutting tools  15  are shaped like a stepped cylinder, each comprising a thinner top tool body  16 , a thicker bottom tool body  17 , and a cutting edge  18  disposed between the thinner top tool body  16  and the thicker bottom tool body  17 . Cylindrical members  19  are respectively fixedly connected to the thicker bottom tool body  17  of each of the rotary cutting tools  15 . Transmission gears  20  are respectively fixedly mounted on the cylindrical members  19 . When the transmission gears  20  meshed with an internal gear  23  in the machine base  2 , the rotary cutting tools  15  are rotated on their own axis during rotary motion of the rotary carrier  4 , and at the same time the cylindrical members  19  are respectively engaged into respective holes  21  in to the flange  22  above the rotary carrier  4 . The rotary cutting tools  15  control the elevation of the axles  10  in the vertical guide holes  9 . The internal gear  23  has a height corresponding to the moving range of the axles  10  in the vertical guide holes  9 . 
     A smoothly arched external cutting tool  25  is fixedly mounted on the machine base  2  and extended through about 288° around the rotary cutting tools  15 . An input gear  26  and an output gear  27  are respectively disposed at two distal ends of the external cutting tool  25 . The external cutting tool  25  has an upper cutting segment  28 , a lower cutting segment  29 , and a cutting edge  30  in the bottom side of the upper cutting segment  28 . The cutting edge  30  is comprised of an inner face  31  and a bottom coating layer  32 . The lower cutting segment  29  has an inner face  33 . 
     A shaft  34  is axially mounted in the column  3 . A rotary table  35  is mounted on the top side of the shaft  34 , having a grained peripheral face  36 . A first bevel gear  37  is fixedly mounted on the bottom side of the shaft  34 . A second bevel gear  38  is meshed with the first bevel gear  37  and coupled to the driving unit  7  through a transmission mechanism  39 . The transmission mechanism  39  is an adjustable transmission gearbox. 
     There is a pitch in the entrance (the position P 1  shown in FIG. 2) between the inner faces  31  and  33  of the external cutting tool  25  and the path for the rotary cutting tools  15  around the longitudinal central axis  5  of the column  3  for receiving cylindrical can body C. 
     During rotary motion of the rotary carrier  4  relative to the peripheral groove  12  in the bottom flange of the column  3 , the rotary cutting tool  15  between the input gear  26  and the output gear  27  is pulled to the area below the external cutting tool  25  (see FIG.  3 ). When moved over the input gear  26 , the rotary cutting tool  15  is guided upwards into the inside of the corresponding can body C. The pitch between the inner face  31  of the external cutting tool  25  and the grained peripheral face  36  of the rotary table  35  is sufficient for the passing of the can body C. During rotary motion of the rotary carrier  4 , the can body C is received in the cutting apparatus  1 . The revolving speed of the rotary table  35  is about twice the speed of the rotary cutting tools  15 , so that the can body C at each rotary cutting tool  15  is respectively turned from the rotary table  35  to the external cutting tool  25 . 
     During the operation of the cutting apparatus  1 , the can body C is squeezed against the inner face  31  of the cutting edge  30 . The pitch between the cutting edge  18  of each rotary cutting tool  15  and the cutting edge of the external cutting tool  25  is gradually reduced in direction from the input end (the side of the input gear  26  toward the output end (the side of the output gear  27 ), so that can bodies C of different heights are cut off at a predetermined cutting line L into equal height. 
     FIG. 7 shows a cutting apparatus  41  suitable for cutting the workpiece into three different heights. According to this alternate form, the fixed external cutting tool  42  of the cutting apparatus  41  comprises three segments, namely, the top cutting segment  43 , the intermediate cutting segment  44 , and the bottom cutting segment  45  disposed at different elevations. The intermediate cutting segment  44  has an inner face  46  and two cutting edges  47  and  48  respectively disposed at the top and bottom sides of the inner face  46 . The rotary cutting tool, referenced by  50 , comprises a shank  51 , a first end block  53  and a second end block  55  respectively provided at the top and bottom ends of the shank  51 , a barrel  54  supported on spring means  52  around the shank  51  between the end blocks  53  and  55 . When standing still, the barrel  54  and the end blocks  53  and  55  are coaxially aligned. Same as the embodiment shown in FIGS. from  1  through  6 , the rotary cutting tools  50  of the cutting apparatus  41  are rotated and moved up and down during the operation of the cutting apparatus  41 . 
     The distance between the inner face  46  of the intermediate cutting segment  44  of the fixed external cutting tool  42  and the longitudinal central axis  5  is gradually reduced in the path. Therefore, the rotary cutting tool  50  gives a pressure to the can body C against the inner face  46  of the intermediate cutting segment  44  of the fixed external cutting tool  42 . Following the reducing of the radius of the inner face  46 , the cutting edges  47  and  48  of the fixed external cutting tool  42  work with the cutting edges  57  and  58  of the rotary cutting tool  50  to cut the workpiece into three heights. During cutting, the barrel  54  is forced to roll off the workpiece. 
     FIGS. 8 and 9 show a cutting apparatus  61  practical for cutting the workpiece into two heights. According to this alternate form, the fixed external cutting tool  62  comprises an upper tool body  65 , a lower tool body  66 , and a cutting blade  63  sandwiched in between the upper tool body  65  and the lower tool body  66 . The cutting blade  63  has a cutting edge  64  perpendicularly aimed at the longitudinal central axis  5 . The upper tool body  65  and the lower tool body  66  have a vertical inner sidewall  67  (see FIG.  9 ). Similar to the embodiment shown in FIGS. 1 and 2, the cutting apparatus  61  comprises a rotary table  35  adapted to be turned about the longitudinal central axis  5  and having a grained peripheral face  36 , a rotary carrier  4  adapted to be turned about the longitudinal central axis  5 , and a plurality of rotary cutting tools  70  respectively mounted in respective guide holes (not shown) in the rotary carrier  4 . The rotary cutting tools  70  function in the same way as that of the embodiment shown in FIGS. 1 and 2. 
     Each rotary cutting tool  70  comprises two cylindrical end blocks  71  and  72 , and a peripheral groove  73  between the end blocks  71  and  72 . The vertical height h 73  of the peripheral groove  73  is about {fraction (10/7)} or 1.43 of the height h 0  of a well-cut can body. 
     In order to guide the can bodies C into the path for cutting, each rotary cutting tool  70  is equipped with two rolling barrels  75  mounted on the rotary carrier  4 . 
     Referring to FIG. 10, the fixed cutting tool  62 ′ comprises a cutting blade  63 ′ having a corrugated cutting edge  64 ′ extended vertically along the length. The rotary cutting tool  70  rolls off the can body C carried thereon, producing a buffering effect when cutting the can body C into two heights. 
     Referring to FIG. 11, a rotary table  80  is turned about the longitudinal central axis. The revolving speed of the rotary table  80  is equal to the rotary carrier  4 . Rollers  81 ,  82 , and  83  are provided at the rotary table  80  and arranged in sets corresponding to the rotary cutting tools  70 . Rollers  81 ,  82 , and  83  are moved with the rotary table  80  relative to the rotary cutting tools  70  to squeeze the can body C on each rotary cutting tool  70 . Each set of rollers include a first roller  81  and a second roller  82  equally spaced from the longitudinal central axis  5 , and a third roller  83  defining with the first roller  81  and the second roller  82  a can body C receiving mouth  84 . 
     Referring to FIG. 12, rollers  88   a ˜ 83   a  and rollers  81   b ˜ 83   b  are symmetrically arranged at top and bottom sidewalls of the rotary table  80 . 
     Referring to FIG. 13, the rotary cutting tool  90  is comprised of a cylindrical shaft  92  and an elastic barrel  91  sleeved onto the. shaft  92 . The elastic barrel  91  is made of elastic material, for example, polyurethane. The peripheral wall of the can body C is supported on the periphery of the elastic barrel  91  and pressed against the cutting blade  63 , and therefore the can body C is cut smoothly without producing a curved edge. 
     Although particular embodiments of the invention have been described in detail for purposes of illustration, various modifications and enhancements may be made without departing from the spirit and scope of the invention. Accordingly, the invention is not to be limited except as by the appended claims.

Technology Classification (CPC): 8