Abstract:
A Venetian blind cutting machine is constructed to include a machine base, two blind locating modules mounted on the machine base at different elevations, each of which having a set of through holes for supporting component parts of a Venetian blind to be cut, a blind carriage adapted to carry the Venetian blind to be cut, a carriage for moving the blind carriage to the elevation of one of the blind locating modules for enabling the Venetian blind to be cut to be put in the selected blind locating module for cut, a cutter provided at the other side of the blind locating modules, and a cutter drive adapted to move the cutter across the imaginary axis passing through each of the through holes of the blind locating modules to cut the component parts of the loaded Venetian blind and then to return the cutter after cutting.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    1. Field of the Invention  
           [0002]    The present invention relates to a Venetian blind cutting machine adapted to cut the headrail, bottom rail, and slats of a Venetian blind to the desired length and, more particularly, to such a Venetian blind cutting machine, which has means to lift/lower the Venetian blind to be cut automatically to the desired elevational cutting position.  
           [0003]    2. Description of the Related Art  
           [0004]    A variety of Venetian blind cutting machines have been disclosed and have appeared on the market. Similar designs are seen in U.S. Pat. Nos. 5,799,557; 5,927,172; 6,089,302. These Venetian blind cutting machines commonly comprise a blind locating assembly having through holes for supporting the headrail, bottom rail, and slats of a Venetian blind to be cut, a cutter, and an air cylinder or reversible motor adapted to drive the cutter to cut the parts of the Venetian blind to the desired length. These Venetian blind cutting machines are commonly used in blind sale centers and operated by a salesman to cut the Venetian blind to the length requested by the consumer buying the Venetian blind. Because the blind locating assembly of a Venetian blind cutting machine fits one particular model of Venetian blinds only. When cutting a different model of Venetian blind, a different blind locating assembly shall be used. It is complicated to change the blind locating assembly of a Venetian blind.  
           [0005]    In order to eliminate the aforesaid problem, Venetian blind cutting machines having two blind locating assemblies are developed. A Venetian blind cutting machine having two blind locating assemblies is suitable for cutting two different types of Venetian blinds.  
           [0006]    Further, a Venetian blind cutting machine has a carriage adapted to carry a Venetian blind to be cut. When a Venetian blind placed on the carriage, it is then pushed into the blind locating assembly for cutting. When a Venetian blind cutting machine having two blind locating assemblies is used, the user may have to adjust the elevation of the blind carriage to the selected blind locating assembly. Because the elevation adjustment structure of the blind carriage is adjusted manually, the adjustment of the blind carriage takes much time and labor.  
         SUMMARY OF THE INVENTION  
         [0007]    The present invention has been accomplished under the circumstances in view. It is therefore one object of the present invention to provide a Venetian blind cutting machine, which has means to automatically move the Venetian blind to the desired elevation for setting into the selected cutting position.  
           [0008]    It is another object of the present invention to provide a Venetian blind cutting machine, which saves much vertical installation space.  
           [0009]    To achieve these objects of the present invention, the Venetian blind cutting machine comprises a machine base, two blind locating modules mounted on the machine base at different elevations, the blind locating modules each having a set of through holes for supporting component parts of a Venetian blind to be cut, a blind carriage adapted to carry the Venetian blind to be cut, a carriage driving mechanism mounted on the machine base at one side of the blind locating modules for moving the blind carriage to the elevation of one of the blind locating modules for enabling the Venetian blind to be cut to be put in the selected blind locating module for cut, a cutter provided at the other side of the blind locating modules, and a cutter drive adapted to move the cutter across the imaginary axis passing through each of the through holes of the blind locating modules to cut the component parts of the loaded Venetian blind to the desired length and then to return the cutter after cutting.  
           [0010]    According to a first embodiment of the present invention, the carriage driving mechanism uses a reversible motor to rotate a double-thread screw rod, causing two movable screw nuts to move two pair of links and to further lift/lower the blind carriage.  
           [0011]    According to a second embodiment of the present invention, air cylinders are used to reciprocate two slides on two parallel sliding rails, causing the slides to move two pairs of links and to further lift/lower the blind carriage. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0012]    [0012]FIG. 1 is a top view of a Venetian blind cutting machine constructed according to a first preferred embodiment of the present invention.  
         [0013]    [0013]FIG. 2 is a side view of the Venetian blind cutting machine according to the first embodiment of the present invention.  
         [0014]    [0014]FIG. 3 is a sectional view in an enlarged scale taken along line  3 - 3  of FIG. 1.  
         [0015]    [0015]FIG. 4 is an operational view of the present invention showing the blind carriage lifted to the elevation of the first blind locating module.  
         [0016]    [0016]FIG. 5 is similar to FIG. 4 but showing the blind carriage lowered to the elevation of the second blind locating module.  
         [0017]    [0017]FIG. 6 is a schematic drawing of a part of the Venetian blind cutting machine according to the second preferred embodiment of the present invention, showing the blind carriage moved between the upper limit position and the lower limit position.  
         [0018]    [0018]FIG. 7 is a top plain view of FIG. 6. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0019]    Referring to FIGS.  1 - 3 , a Venetian blind cutting machine  1  in accordance with the first preferred embodiment of the present invention is shown comprised of a machine base  10 , two blind locating modules, namely, the first blind locating module  20  and the second blind locating module  30 , a cutter unit  40 , a limiter  50 , and a die block adjustment mechanism  60 .  
         [0020]    The machine base  10  comprises a base support frame  11 , and a vertical mount  12  located on the top side of the base support frame  11 . The vertical mount  12  has a first side  121 , a second side  122  opposite to the first side  121 , and two openings (not shown) cut through the first side  121  and the second side  122  at different elevations.  
         [0021]    The blind locating modules  20  and  30  each have a first side  21  or  31 , a second side  22  or  32  opposite to the first side  21  or  31 , through holes  23  or  33 , and die blocks  24  or  34 . The through holes  23  and  33  of the blind locating modules  20  and  30  are made subject to the cross-sections of the component parts of two different types of Venetian blinds, so that the component parts of two different types of Venetian blinds can be respectively positioned in the through holes  23  and  33  of the blind locating modules  20  and  30 . The blind locating modules  20  and  30  are respectively mounted on the vertical mount  12  of the machine base  10  at different elevations, keeping the first sides  21  and  31  of the blind locating modules  20  and  30  respectively attached to the second side  122  of the vertical mount  12  and the through holes  23  and  33  of the blind locating modules  20  and  30  respectively aimed at the openings of the vertical mount  12 . The two opposite sides corresponding to the first sides  21  and  31  and second sides  22  and  32  of the blind locating modules  20  and  30  are defined hereinafter as the first lateral side and the second lateral side respectively.  
         [0022]    The cutter unit  40  comprises two cutters  41  and  42 , and a cutter drive  43 . The cutters  41  and  42  are respectively coupled to a respective transverse sliding track at the second sides  22  and  32  of the blind locating modules  20  and  30  for a reciprocating motion on the respective transverse sliding track. The reciprocating paths provided by the transverse sliding tracks at the second sides  22  and  32  of the blind locating modules  20  and  30  pass across the imaginary axes passing through the through holes  23  and  33  of the blind locating modules  20  and  30  respectively, so that the cutters  41  and  42  can be moved across the imaginary axes passing through the through holes  23  and  33 . The cutter drive  43  comprises a reversible motor  431  mounted on the machine base  10 , and a transmission gear set  433  formed of transmission gears  433   a  and  433   b  and a rack  433   c  and coupled between the output shaft  432  of the reversible motor  431  and the cutters  41  and  42  for reciprocating the cutters  41  and  42  along the transverse sliding tracks at the second sides  22  and  32  of the blind locating modules  20  and  30 . During each reciprocating cycle, the cutters  41  and  42  are moved across the imaginary axes passing through the through holes  23  and  33  and then returned to their former positions.  
         [0023]    The limiter  50  comprises a rack  51  mounted on the machine base  10 , two pairs of sliding rails  52  respectively made of round rods and mounted in the rack  51  at different elevations corresponding to the through holes  23  and  33  of the blind locating modules  20  and  30 , two slides  53  respectively and slidably coupled to the pairs of sliding rails  52 , two stop plates  54  respectively mounted on the slides  53  and extended across the imaginary axes passing through the through holes  23  and  33  and adapted to stop the slats of the Venetian blinds being inserted through the through holes  23  and  33  of the blind locating modules  20  and  30  for cut, and two coil springs  55  respectively mounted on the sliding rails  52  and stopped against the slides  53 .  
         [0024]    The die block adjustment mechanism  60  is located on the machine base  10 , and adapted to adjust the positions of the die blocks  24  and  34  of the blind locating modules  20  and  30  manually.  
         [0025]    The structure of the aforesaid Venetian blind cutting machine is similar to the conventional designs. The operation of the Venetian blind cutting machine is outlined hereinafter. At first, the operator insert the component parts of one of the two different Venetian blinds from the first lateral side through the through holes  23  or  33  of the blind locating modules  20  and  30  to the second lateral side, enabling the corresponding ends of the component parts of the inserted Venetian blinds to be respective topped at the stop plates  54 . Thereafter, the operator starts the cutter drive  43  of the cutter unit  40  to feed the cutters  41  and  42 , causing the cutters  41  and  42  to cut the component parts of the inserted Venetian blinds to the desired length.  
         [0026]    The Venetian blind cutting machine further comprises a blind carriage  70 , and a carriage driving mechanism  80 . The carriage driving mechanism  80  comprises a base framework  81  located on the machine base  10 , a reversible motor  82 , a double-thread screw rod  83 , two transmission devices  84 , and four links  85 . The base framework  81  comprises a platform  811 , and two side plates, namely, the first side plate  812  and the second side plates  813  vertically disposed at two lateral sides of the platform  811 . The reversible motor  82  is located on the first side plate  812 , keeping the output shaft (not shown) thereof suspended above the platform  811 . The double-thread screw rod  83  has one end coupled to the output shaft of the reversible motor  82 , a middle part supported in an axle bearing in an upright axle holder  814  at the platform  811 , and the other end supported in an axle bearing in the second side plate  813 . The two threads  831  and  832  of the double-thread screw rod  83  extend in reversed directions. The transmission devices  84  are screw nuts respectively threaded onto the threads  831  and  832  of the double-thread screw rod  83 . The links  85  are respectively and bilaterally pivoted with one end thereof to the transmission devices  84 . The blind carriage  70  has four pivot holders  71  fixedly provided at the bottom sidewall thereof in four corners, and respectively pivoted to the other end of each of the links  85 . The blind carriage  70  is maintained in horizontal in the first lateral side relative to the blind locating modules  20  and  30 .  
         [0027]    When started the reversible motor  82  to rotate the double-thread screw rod  83 , the screw nuts  84  are moved relative to each other along the double-thread screw rod  83 , thereby causing the links  85  are moved to lift or lower the blind carriage  70  between the elevation of the first blind locating module  20  and the elevation of the second blind locating module  30 .  
         [0028]    Further, sensors, for example, limit switches (not shown) are provided at locations within the path of the screw nuts  84  to control the upper and lower limit positions of the blind carriage  70 , enabling the blind carriage  70  to be stopped at the elevation of first blind locating module  20  or the elevation of the second blind locating module  30 .  
         [0029]    Referring to FIGS. 4 and 5, by means of the blind carriage  70  and the carriage driving mechanism  80 , the operator can carry a Venetian blind to be cut on the blind carriage  70  to the elevation of the first blind locating module  20  as shown in FIG. 4, or the elevation of the second blind locating module  30  as shown in FIG. 5 subject to the type of the Venetian blind carried on the blind carriage  70 . If the Venetian blind must be set in the first blind locating module  20  for cutting, the operator can control the carriage driving mechanism  80  to lift the blind carriage  70  to the elevation of the first blind locating module  20  as shown in FIG. 4, and then put the component parts of the Venetian blind on the blind carriage  70 , and then push the component parts of the Venetian blind through the through holes  23  of the first blind locating module  20 , and then operate the cutter unit  40  to cut the component parts of the Venetian blind to the desired length. If the Venetian blind must be set in the second blind locating module  30  for cutting, the operator can control the carriage driving mechanism  80  to lower the blind carriage  70  to the elevation of the second blind locating module  30  as shown in FIG. 5, and then put the component parts of the Venetian blind on the blind carriage  70 , and then push the component parts of the Venetian blind through the through holes  33  of the second blind locating module  30 , and then operate the cutter unit  40  to cut the component parts of the Venetian blind to the desired length.  
         [0030]    By means of controlling the carriage driving mechanism  80 , the blind carriage  70  is automatically adjusted to the desired elevation for enabling the workpiece to be set into position for cutting by the cutter unit  40 . Therefore, the blind cutting machine saves much labor and time.  
         [0031]    When the carriage  70  lowered to the lower limit position (the elevation of the second blind locating module  30 ), the links  85  are approximately set in horizontal and received in between the blind carriage  70  and the platform  811  of the base framework  81  of the carriage driving mechanism  80 . At this time, the height between the base framework  81  and the blind carriage  70  is minimized, i.e., the installation of the carriage driving mechanism  80  does not occupy much vertical installation space.  
         [0032]    [0032]FIGS. 6 and 7 show the second preferred embodiment of the present invention. Similar to the aforesaid first embodiment of the present invention, the blind cutting machine according to the second embodiment of the present invention is comprised of a machine base, two blind locating modules, a cutter unit, a limiter, and a die block adjustment mechanism. This embodiment further comprises a blind carriage  70  and a carriage driving mechanism  90 .  
         [0033]    The carriage driving mechanism  90  comprises a base framework  91  located on the machine base, two sliding rails  92 , two air cylinders  93 , two slides  94 , and four links  95 . The base framework  91  comprises a platform  911 , and two side plates  912  vertically disposed at two lateral sides of the platform  911 . The sliding rails  92  are connected between the side plates  912  and arranged in parallel. The air cylinders  93  are respectively mounted in the side plates  912 , each having a piston rod  931  suspended above the platform  911  between the sliding rails  92 . The slides  94  are slidably mounted on the sliding rails  92  and coupled to the piston rods  931  of the air cylinders  93 . The links  95  are respectively and bilaterally pivoted with one end thereof to the slides  94 . The blind carriage  70  has four pivot holders  71  fixedly provided at the bottom sidewall thereof in four corners and respectively pivoted to the other end of each of the links  95 . The blind carriage  70  is maintained in horizontal in the first lateral side relative to the blind locating modules.  
         [0034]    When compressed air provided to the air cylinders  93  to extend out the piston rods  931 , the slides  94  are moved along the sliding rails  92  toward each other to lower the blind carriage  70  to the lower limit position. On the contrary, when compressed air provided to the air cylinders  93  to pull back the piston rods  931 , the slides  94  are moved along the sliding rails  92  apart from each other to lift the blind carriage  70  to the upper limit position.