Abstract:
A manufacturing method for efficiently cutting a pocket coil spring row which is incorporated and used in a chair, sofa, or bed mattress into lengths suitable for the use without waste of the material is provided wherein a method for double-sealing a separating portion between adjacent pocket coil springs at an arbitrary length position of a serial pocket coil spring row by means of ultrasonic welding or impulse welding and cutting a portion between the double seals with a cutter knife is provided.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The present invention relates to a sealing and cutting device for a pocket coil row which efficiently cuts a pocket coil spring row to be incorporated and used in furniture such as a chair or a sofa or bedding such as a bed mattress into lengths suitable for the use without waste. 
         [0003]    2. Description of the Related Art 
         [0004]    Conventionally, as shown by the reference numeral  4  in  FIG. 10  and also shown in U.S. Pat. No. 5,792,309, a method is employed in which when forming a pocket coil spring row, an empty pocket part that contains no coil spring is formed at a position of a length suitable for the use, and this empty pocket part is cut. However, this method wastes nonwoven cloth at the empty pocket part, and as the number of empty pocket parts increases, the capacity of production lowers. 
         [0005]    In view of the above-described point, an object of a sealing and cutting device for a pocket coil row according to the invention is not to form the empty pockets that contain no coil spring to eliminate the waste of nonwoven cloth and increase the capacity of production. 
       SUMMARY OF THE INVENTION 
       [0006]    To achieve the object, the sealing and cutting device for a pocket coil row according to the invention seals and cuts a serial pocket coil row formed in a row in which coil springs are housed one by one in each of connected cylinders in pocket shapes made of nonwoven cloth or fabric every arbitrarily preset number of cylinders, characterized by: sealing means for double-sealing, cutting means for cutting a portion between the double seals by moving a cutting blade, and conveying means for conveying the pocket coil row. 
         [0007]    In addition, according to the sealing and cutting device of the invention, the sealing means is an ultrasonic welder having a horn with a narrow groove for passage of a cutting blade, the sealing means is provided with an impulse heater wire on both sides of a cutting blade running line, a converter horn of the ultrasonic welder has a mechanism that moves up and down by about ½ or more of the coil spring diameter, the ultrasonic welder includes an upper die and a lower die and the lower die has a mechanism that moves up and down by about ½ or more of the coil spring diameter, or the ultrasonic welder includes an upper die and a lower die and the lower die is divided into two and the cutting blade is movable at the dividing center. 
         [0008]    According to a conventional method, to prevent popping-out of coil springs described above, an empty pocket  4  that contains no coil spring is formed as shown in  FIG. 8  and  FIG. 10  and the center of the empty pocket is set as a cutting line  7  to prevent popping-out of the coil springs, however, this method has great disadvantages such that the material is wasted and the production efficiency lowers, however, the present invention solves these problems at one time. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0009]      FIG. 1  is a side view schematically showing an ultrasonic sealing and cutting device for cutting a pocket coil spring row into determined sizes; 
           [0010]      FIG. 2  is an enlarged side view of a major part of the invention of  FIG. 1 ; 
           [0011]      FIG. 3  is a front view schematically showing an ultrasonic sealing and cutting device for cutting a pocket coil spring row into determined sizes; 
           [0012]      FIG. 4  is an enlarged side view of a major part of the invention schematically showing an impulse sealing and cutting device for cutting a pocket coil spring row into determined sizes; 
           [0013]      FIG. 5  is a front view schematically showing the impulse sealing and cutting device for cutting a pocket coil spring row into determined sizes; 
           [0014]      FIG. 6  is an enlarged side view of a portion double-sealed and cut of a pocket coil spring row; 
           [0015]      FIG. 7  is a top view of the portion double-sealed and cut of a pocket coil spring row; 
           [0016]      FIG. 8  is a top view of a portion of a pocket coil spring row cut by the conventional method; 
           [0017]      FIG. 9  is a perspective view showing a position to be double-sealed and cut of a pocket coil spring row; and 
           [0018]      FIG. 10  is a perspective view showing a position to be cut of a pocket coil spring row by the conventional method. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0019]    An embodiment of the invention will be described with reference to the drawings.  FIG. 1  is a side view schematically showing a device equipped with an ultrasonic welding and sealing device,  FIG. 2  is an enlarged view of a major part of  FIG. 1 , and  FIG. 3  is a front view thereof. 
         [0020]    The reference numeral  1  in the drawings denotes a serial pocket coil spring row, and the reference numeral  20  in the drawings denotes a conveyor for conveying the serial pocket coil spring row. 
         [0021]      FIG. 1  and  FIG. 2  show a state in that a horn  10  is at a lowered position and a pair of left and right anvils  14   a  and  14   b  are at raised positions, double sealing is performed by ultrasonic waves, and a portion between the double seals is cut. 
         [0022]      FIG. 3  shows a state in that the horn  10  is at a raised position and the anvils  14   a  and  14   b  are at lowered positions, the distance between the lower surface of the horn  10  and the upper surfaces of the anvils  14   a  and  14   b  is set to be substantially not less than the diameter of the pocket coil spring so that the pocket coil spring row  1  passes through this space. 
         [0023]    The ultrasonic device is composed of a converter  11 , the horn  10 , and a power supply (not shown). 
         [0024]    The converter  11  and the horn  10  are anchored by screws, and the converter  11  is connected to the power supply (not shown) by a cable. 
         [0025]    The converter  11  is anchored to a sliding portion of a cylinder  12  and structured to be movable up and down, and its vertical movement amount is set to be substantially not less than ½ of the pocket coil spring diameter so as not to inhibit the conveyance of the pocket coil spring row  1 . 
         [0026]    On the lower end portion of the horn  10 , a groove  10   a  through which a cutter knife  15  passes is formed. 
         [0027]    Concerning the anvils, the right anvil  14   a  and the left anvil  14   b  are disposed symmetrically so as to allow the cutter knife  15  to pass through. 
         [0028]    The right anvil  14   a  is anchored to a supporting plate  23   a , and the supporting plate  23   a  is fixed to a cylinder base  25 . 
         [0029]    The left anvil  14   b  is anchored to the supporting plate  23   b , and the supporting plate  23   b  is fixed to the cylinder base  25 . 
         [0030]    The cutter knife  15  is fixed to a cutter knife attaching base  21  by a cutter knife holder  22 , and the cutter knife attaching base  21  is fixed to a slider base of a rodless cylinder  16 . 
         [0031]    The cutter knife  15  is structured to run between the right anvil  14   a  and the left anvil  14   b.    
         [0032]    The cylinder base  25  is fixed to the cylinder rod base  27  of the cylinder  17  and structured to move up and down, and its vertical movement amount is set to be not less than about ½ of the pocket coil spring diameter so as not to disturb conveyance of the pocket coil spring row  1 . 
         [0033]    When the horn  10  is at the raised position and the anvils  14   a  and  14   b  are at the lowered positions, the conveyor  20  rotates to convey the pocket coil spring row  1  on a conveyor belt  18 . 
         [0034]    At this time, the number of springs is sensed by a sensor  13 , and the conveyor  20  is stopped at a number preset in the counter. 
         [0035]    Next, the horn  10  is lowered, and simultaneously, the anvils  14   a  and  14   b  are raised, and nonwoven cloth between the pocket coil spring and the pocket coil spring adjacent to each other is sandwiched by the lower surface of the horn  10  and the upper surfaces of the anvils  14   a  and  14   b.    
         [0036]    Thereafter, by turning the power supply of the ultrasonic device ON to make the horn  10  to generate ultrasonic waves, right sealing  6   a  and left sealing  6   b  are simultaneously performed as shown in  FIG. 7 . 
         [0037]    Substantially simultaneously with this, the rodless cylinder  16  works to move the cutter knife  15 , and this cutter knife  15  cuts a cutting line  7  between the right sealing  6   a  and the left sealing  6   b.    
         [0038]    Therefore, the left pocket coil of the pocket coil springs adjacent to each other across the cutting line  7  is closed by the left sealing  6   b , and the right pocket coil spring is closed by the right sealing, so that the coil springs are prevented from popping out even when the cutting line  7  is cut. 
         [0039]    If the right sealing  6   a  and the left sealing  6   b  are not made, when the cutting line  7  is cut, either of the adjacent pockets bursts and the coil spring in the pocket pops out. 
         [0040]    According to the conventional method, to prevent popping-out of a coil spring described above, as shown in  FIG. 8  and  FIG. 10 , a pocket  4  that contains no coil spring is formed and a center thereof is set as a cutting line  7  to prevent popping-out of the coil spring, however, this method has a great disadvantage such that the material is wasted and the production efficiency lowers, however, the present invention has solved these problems at one time. 
         [0041]      FIG. 4  and  FIG. 5  are schematic views of an impulse sealing method which uses an impulse heat sealing method instead of ultrasonic sealing. 
         [0042]    According to this method, impulse heater wires  36   a  and  36   b  are disposed on the upper surfaces of the right anvil  37   a  and the left anvil  37   b , respectively, and by these impulse heater heats, the right sealing  6   a  and the left sealing  6   b  are formed, and other structures are substantially the same as those of the ultrasonic sealing method described above, so that description thereof is omitted.