Abstract:
Disclosed herein is a cushioning material for packing an object, such as an electrical product, kitchen utensils, an industrial machine, etc., to protect it from outside shocks. In the cushioning material of the present invention, embossments defining spaces are formed in a synthetic resin film constituting the cushioning material, and porous elastic balls are provided in the respective spaces. Thus, the cushioning material of the present invention can be wound in a roll shape while the elastic balls are pressed and reduced in volume. Therefore, a large amount of cushioning material can be loaded when being carried, thereby logistics costs are markedly reduced. Furthermore, the cushioning material of the present invention may be received in a roll casing such that a user can easily handle the cushioning material.

Description:
CROSS REFERENCE  
       [0001]     Applicant claims foreign priority under Paris Convention and 35 U.S.C. § 119 to a Korean Patent Application No. 10-2005-0095054, filed Oct. 10, 2005 with the Korean Intellectual Property Office.  
       BACKGROUND OF THE INVENTION  
       [0002]     1. Field of the Invention  
         [0003]     The present invention relates generally to cushioning materials made of synthetic resin films and used for packing objects, such as electrical products, kitchen utensils, industrial machines, etc., to protect them from outside shocks and, more particularly, to a cushioning material for packing, in which a plurality of spaces is formed in a synthetic resin film and porous elastic balls are provided in respective spaces, so that, when the cushioning material is carried, it is reduced in volume by being pressed, and, when the cushioning material is used, the elastic balls, which have been pressed, are expanded and thus serve as cushions, and which may be wound in a roll shape and received in a roll casing, such that a user can conveniently cut and use a desired length of cushioning material.  
         [0004]     2. Description of the Related Art  
         [0005]     As shown in  FIG. 1 , a typical cushioning material  100  for packing includes a synthetic resin film  111 , which consists of two layers and has a plurality of spaces  140 , which are filled with air and defined between the two layers, so as to have an embossed structure. The spaces  140  are sealed by welding portions of the two layers around the spaces  140  to each other.  
         [0006]     The conventional embossed cushioning material having the spaces charged with air has advantages in that superior cushioning ability is ensured and it is soft. However, because embossments defining the spaces charged with air are relatively fragile, they are easily broken by outside impact, so that the cushioning material may not be able to serve its intended function. Furthermore, when the cushioning material is wound in a roll shape to be stored or carried, because the volume thereof is relatively large due to the embossments defining the spaces filled with air, logistics costs are increased, and it is inconvenient to treat it.  
         [0007]     In addition, because the conventional cushioning material made of a synthetic resin film is marketed in a wound state in a roll shape, when a user uses the cushioning material, a desired length is cut and, thereafter, the remaining cushioning material must be tied using a separately provided string.  
         [0008]     Here, if the cushioning material is undesirably unwound due to the carelessness of the user, the user must again wind the cushioning material into a roll. As such, the conventional cushioning material is problematic in that it is inconvenient to the user and thus reduces workability.  
       SUMMARY OF THE INVENTION  
       [0009]     Accordingly, the present invention has been made keeping in mind the above problems occurring in the prior art, and an object of the present invention is to provide a cushioning material for packing in which porous elastic balls are provided in respective spaces which are formed in a synthetic resin film constituting the cushioning material, so that, when the cushioning material is wound in a roll shape, the porous elastic balls are pressed and the cushioning material is reduced in volume, thus a large amount of cushioning materials can be loaded to be carried, thereby logistics costs are markedly reduced.  
         [0010]     In order to accomplish the above object, the present invention provides a cushioning material for packing, including a synthetic resin film having an upper layer and a lower layer, with embossments formed in the synthetic resin film by forming spaces between the upper layer and the lower layer of the synthetic resin film and by heat-welding portions of the upper and lower layers, surrounding the spaces, to each other. A porous elastic ball is provided in each of the spaces defined in the embossments.  
         [0011]     Preferably, a through hole, communicating with each space having the elastic ball therein, may be formed at a predetermined position around each space through the upper or lower layer of the synthetic resin film.  
         [0012]     Furthermore, the porous elastic ball may comprise a plurality of small elastic balls provided in each of the spaces. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0013]     The above and other objects, features and advantages of the present invention will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which:  
         [0014]      FIG. 1  is a sectional view showing a conventional air cushioning material for packing;  
         [0015]      FIG. 2   a  is a sectional view of a cushioning material having porous elastic balls therein, according to an embodiment of the present invention;  
         [0016]      FIG. 2   b  is a sectional view showing the shape of the cushioning material of  FIG. 2   a  when it is pressed;  
         [0017]      FIG. 3  is a partially exploded perspective view showing a roll casing, in which the cushioning material according to the present invention is provided;  
         [0018]      FIG. 4  is a sectional view showing the roll casing of  FIG. 3 ;  
         [0019]      FIG. 5   a  is a sectional view of a cushioning material having porous elastic balls therein, according to another embodiment of the present invention;  
         [0020]      FIG. 5   b  is a sectional view showing the shape of the cushioning material of  FIG. 5   a  when it is pressed; and  
         [0021]      FIG. 6  is a perspective view showing a roll of cushioning material having porous elastic balls according to the present invention. 
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0022]     Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings.  
         [0023]     In a cushioning material  10  according to an embodiment of the present invention, a plurality of spaces  14  is formed in a synthetic resin film  11 , so that the outer surface of the cushioning material is embossed.  
         [0024]     In detail, the spaces  14 , which form the embossments, are defined between an upper layer  12  and a lower layer  13  constituting the synthetic resin film  11 . A porous elastic ball  20 , for example, an EPP (expanded poly propylene) ball or an EPS (expanded poly styrene) ball, is placed in each space  14 , and the upper layer  12  and lower layer  13  are welded by heating around the circumferential outer edges of the spaces  14 , such that the porous elastic balls  20  can serve as cushions.  
         [0025]     Furthermore, each space  14  communicates with outside air through a through hole  15 , which is formed at a predetermined position around the space  14  in the synthetic resin film  11 .  
         [0026]     Meanwhile, a plurality of small porous elastic balls may be provided in each space  14 .  
         [0027]     The cushioning material  10  of the present invention having the above-mention structure may be received in a box-shaped roll casing  30 , which has a plurality of guide rollers  31  therein, after being pressed and wound in a roll shape.  
         [0028]     The box-shaped roll casing  30  has an outlet  32  in one surface thereof. A cutting tool  33  is provided under the outlet  32  such that the cushioning material  10  can be easily cut by the cutting tool  33 .  
         [0029]     The roll casing  30  is not a critical element of the present invention but will also be explained for the sake of clear comprehension of the present invention.  
         [0030]     The roll casing  30  may be constructed such that the part provided above the outlet  32  is openable like a lid. In the case of a large roll casing  30 , an openable door is preferably formed in one end of the roll casing  30  such that a cushioning material  10  can be installed in a horizontal direction. The lid, which is provided at an upper position, or the door, which is provided on one end of the roll casing  30 , has a structure that is well known in the art, therefore further explanation is deemed unnecessary.  
         [0031]     Meanwhile, to manufacture the cushioning material  10  of the present invention, the upper layer  12  and the lower layer  13  of the synthetic resin film  11  overlap each other and are pressed and adhered to each other by heating while a plurality of spaces  14  is formed in the synthetic resin film  11 .  
         [0032]     In detail, the upper layer  12  and the lower layer  13  are unwound from the respective rollers and, thereafter, a forming roller, which is disposed at a predetermined position, presses the upper layer  12  such that the spaces  14  are formed between the upper and lower layers  12  and  13 . Subsequently, the upper and lower layers  12  and  13  are moved and hot-pressed by a hot press. Here, after the upper layer  12  is pressed to form the spaces, a separate elastic ball supply machine supplies porous elastic balls  20  in the respective spaces  14 . Thereafter, the upper and lower layers  12  and  13  are hot-pressed at positions around the spaces  14  by the hot press.  
         [0033]     In the above process, depending on the method of manufacturing the cushioning material, liquid resin may be supplied as the material of the upper and lower layers  12  and  13  of the cushioning material.  
         [0034]     After the cushioning material has been completed, the cushioning material is pressed by a pressing roller, such that the porous elastic balls  20  provided in the spaces  14  are flattened. Thereafter, the cushioning material is wound in a roll shape and is inserted into the roll casing  30 .  
         [0035]     The synthetic resin film for the cushioning material of the present invention is the same as that of a typical cushioning material.  
         [0036]     Meanwhile, the roll casing  30  has a hexahedral box shape. The guide rollers  31  are provided on the four respective inner surfaces of the roll casing  30  to support the outer surface of the roll of cushioning material  10 , which is received in the roll casing  30 .  
         [0037]     The guide rollers  31 , which are provided on the inner surfaces of the roll casing  30 , serve to support the cushioning material  10 , which is rotatably fitted over a support shaft  34 , such that the porous elastic balls  20 , which are placed in the spaces  14  of the synthetic resin film  11 , can maintain the compressed state without expanding into ball shapes, and such that, when the end of the cushioning material  10  is pulled out through the outlet  32  of the roll casing  30 , the roll of cushioning material  10  can be smoothly rotated.  
         [0038]     The opposite ends of each guide roller are supported by a pair of support pieces, which are provided on each inner surface of the roll casing  30 . Here, the diameters of support holes of the support pieces, in which the respective opposite ends of the guide roller are inserted, are greater than the diameters of the opposite ends of the guide roller, so that clearance is ensured therebetween, and the guide roller can be elastically moved in a radial direction of the roll of cushioning material in the support holes of the support pieces. Therefore, even if the cushioning material  10 , which is fitted over the support shaft  34 , increases in volume while being used, because the guide rollers  31  support the roll of cushioning material  10  when it is rotated, the cushioning material  10  can be smoothly extracted outside through the outlet  32 .  
         [0039]     Furthermore, the cutting tool  33  is provided under the outlet  32  on the outer surface of the roll casing  30 , so that the cushioning material  10  can be easily cut by the cutting tool  33 .  
         [0040]     Meanwhile, because the elastic ball  20 , which is placed in each space  14  of the synthetic resin film  11 , is porous, when predetermined force is applied to the elastic ball  20 , the elastic ball  20  is flattened, that is, is reduced in volume. When the force is removed, the elastic ball  20  is elastically returned to the initial state thereof.  
         [0041]     Therefore, when the cushioning material  10  is wound in a roll shape, if the cushioning material  10  is wound after the elastic balls  20 , which are placed in the respective spaces  14  of the synthetic resin film, have been pressed by the pressing roller such that the thicknesses thereof are reduced to 50%, the volume of the rolled cushioning material  10  is reduced to ¼ the volume of a conventional rolled cushioning material, the spaces of which are fully filled with air. Thus, the cushioning material  10  of the present invention is advantageous in that the volume thereof is markedly reduced when wound in a roll shape, compared to that of the conventional cushioning material, so that logistics costs are reduced. In other word, there is an advantage in that, when each elastic ball  20  is reduced in thickness by only 50%, the volume of the roll of cushioning material is reduced to ¼ of its original volume.  
         [0042]     Furthermore, when each elastic ball  20 , which is placed in each space  14  of the synthetic resin film, is flattened by being pressed, air in the space  14  is discharged outside through the through hole  15 . When the elastic ball  20  is returned to the initial size thereof, air is drawn into the space  14  through the through hole  15 .  
         [0043]     As such, it is preferable that the through hole  15 , which communicates with each space  14 , be formed to smoothly contract and expand the elastic ball  20 , which is placed in the space  14 . However, as required, no through hole may be formed around the space  14  in which the elastic ball  20  is placed. The intended purpose of the present invention is also achieved by this case.  
         [0044]     Furthermore, when the cushioning material  10  of the present invention is received in the roll casing  30  after being pressed to 50% of its original thickness and being wound in a roll shape, the guide rollers  31 , which are provided in four directions in the roll casing  30 , support the outer surface of the roll of cushioning material  10 , thus maintaining the elastic balls  20  in the pressed state.  
         [0045]     In the above state, in which the roll of cushioning material  10  is received in the roll casing  30 , when a user pulls the outer end of the cushioning material  10  to discharge a desired length thereof outside through the outlet  32  and cuts it using the cutting tool  33 , the diameter of the roll of cushioning material  10  is reduced, so that the outer surface of the roll is instantaneously spaced apart from the guide rollers  31 , but the elastic balls  20 , which are placed in the spaces  14  positioned at the outermost positions of the roll, are returned to the original sizes thereof, thereby the roll of cushioning material  10  is again supported by the guide rollers  31 .  
         [0046]     Furthermore, as the cushioning material  10  is used, when the diameter of the roll of cushioning material  10  is reduced to a predetermined extent, the roll of cushioning material  10  is no longer supported by the guide rollers  31 . However, in this state, even if the elastic balls  20  in the spaces  14  are returned to the original sizes thereof, the roll of cushioning material  10  can freely rotate in the roll casing  30 , thus the user is able to use it without inconvenience.  
         [0047]     The roll casing  30  may be changed in size depending on the length of the cushioning material  10 . Preferably, the roll casing  30  is made of one selected from metal, nonferrous metals, synthetic resin or paper.  
         [0048]     Furthermore, the presence of the support shaft  34 , which is longitudinally installed at a center position in the roll casing  30 , is selectively determined depending on the size of the roll casing  30 .  
         [0049]     If the piece of cushioning material  10  is relatively long, so that the roll of cushioning material  10  is relatively large, a relatively large roll casing  30  is used. If the roll of cushioning material  10  is relatively small, a relatively small roll casing  30  is used. As such, the roll casing  30  is preferably manufactured in various sizes depending on the standard sizes of the roll of cushioning material  10 .  
         [0050]     In the case of a large roll casing  30 , the support shaft  34  is installed in the roll casing  30 , and the cushioning material  10  is fitted over the support shaft  34 . Thus, when it is desired to use the cushioning material  10 , the cushioning material  10  can be easily discharged thanks to the support of both the guide rollers  31 , which correspond to the outer surface of the roll of cushioning material  10 , and the support shaft  34 , which is longitudinally provided in the roll casing  30 .  
         [0051]     In the case in which the roll of cushioning material  10  is relatively small, only the guide rollers  31  are provided in the roll casing  30 , and the support shaft  34  is not installed, but there is still no difficulty in discharging the cushioning material  10 .  
         [0052]     Meanwhile, the cutting tool  33 , which is provided under the outlet  32  on the roll casing  30  to cut the cushioning material  10 , is made of metal or plastic. The cutting tool  33  is satisfactory as long as it is able to cut the cushioning material  10 .  
         [0053]     Furthermore, the cutting tool  33  is mounted to the roll casing  30  using a well known mounting method, such as a riveting method, a bolt coupling method, etc.  
         [0054]     In the present invention, in the case of a roll casing  30  having no support shaft, a portion of the roll casing  30  above the outlet  32  serves as an openable lid, so that a cushioning material  10  is received in the roll casing  30  through the lid without a support shaft. In the case of a large roll casing  30 , a door is provided on one end of the roll casing  30 , so that a cushioning material  10  is fitted over the support shaft  34  in a horizontal direction.  
         [0055]     In another embodiment of the present invention, a plurality of small elastic balls may be provided in each space  14  of a cushioning material  10  for packing.  
         [0056]     In this embodiment, when the cushioning material  10  is manufactured, a plurality of small elastic balls, each having a diameter ranging from 1 mm to 5 mm, is provided in each space  14 , unlike the former embodiment, in which one elastic ball is provided in each space  14  of the cushioning material  10 .  
         [0057]     Hereinafter, the drawings attached to the present invention will be explained in brief.  
         [0058]      FIG. 2   a  is an illustrative view showing the cushioning material  10 , in which protrusions for forming the spaces  14  are formed in one direction and the elastic balls  20  are provided in the respective spaces  14 , showing the state in which the elastic balls  20  that are placed in the spaces  14  of the cushioning material  10  maintain sphere shapes, for example, when the cushioning material  10  is first manufactured, or when the elastic balls are returned to the original shapes thereof after having been pressed.  
         [0059]      FIG. 2   b  is an illustrative view showing the state in which the cushioning material  10  of  FIG. 2   a  having the elastic balls  20  is pressed, showing the state in which the elastic balls  20  in the spaces  14  are pressed by the pressing roller such that the thickness thereof is reduced to 50%, for example, in order to market the cushioning material  10 .  
         [0060]     Here, when the elastic balls  20  are contracted or expanded in the spaces  14 , air in the spaces  14  is discharged outside or is drawn into the spaces  14  through the through holes  15 , which are formed around the respective spaces  14  in the synthetic resin film  11 .  
         [0061]      FIG. 3  is a partially exploded perspective view showing the roll casing  30 , in which the cushioning material  10  is provided.  FIG. 4  is a sectional view showing the roll casing  30  of the present invention, and showing the cushioning material  10 , which is pressed such that the thickness of the elastic balls  20 , which are provided in the respective spaces  14  formed in the cushioning material  10 , is reduced by 50%, and is received in the roll casing  30  after being wound in a roll shape.  
         [0062]     At this time, the cushioning material  10  is supported by the guide rollers  31 , which are provided on the four respective inner surfaces of the roll casing  30 , such that it can be smoothly extracted outside through the outlet  32  of the roll casing  30 .  
         [0063]      FIG. 5   a  is an illustrative view showing the cushioning material  10  for packing according to the present invention, in which protrusions for forming spaces  14  are formed in opposite directions.  FIG. 5   b  is an illustrative view showing a pressed state of the cushioning material  10  of  FIG. 5   a  having the elastic balls. That is,  FIGS. 5   a  and  5   b  are illustrative views of the case, in which the spaces  14  protrude in opposite directions. The operation and effect of the cushioning material  10  of  FIGS. 5   a  and  5   b  are equal to those of the cushioning material  10  of  FIGS. 4   a  and  4   b.    
         [0064]      FIG. 6  is an illustrative view showing a roll of cushioning material  10  having porous elastic balls  20  according to the present invention, showing the cushioning material  10  wound in a roll shape after being pressed. Here, the cushioning material  10 , which is wound in a roll shape, may be received in the roll casing  30 , or may be packed using a vinyl sheet. In the case in which the user uses the cushioning material  10  in small amounts, the cushioning material  10  is preferably received in the roll casing  30 . In the case in which a large amount of cushioning material  10  is used at one time, for example, at a construction site, the cushioning material  10 , which is wound in a roll shape after being pressed, is packed by a vinyl sheet, a synthetic resin warp, a fabric sheet, or a paper sheet, and is supplied to the desired place.  
         [0065]     That is, even though the cushioning material  10 , which is wound in a roll shape, is wrapped with a vinyl sheet, the elastic balls can maintain the pressed state as long as the cushioning material  10  is not unwound. At a site, a large amount of cushioning material must be used at one time. In the case of the cushioning material  10 , which is received in the roll casing  30 , because the speed at which the cushioning material  10  is unwound is relatively slow, it is inefficient. Therefore, at a construction site, the cushioning material  10 , which is wrapped with a vinyl sheet so that it can be easily used after the vinyl sheet has been cut, can be used.  
         [0066]     As such, in the present invention having the above-mentioned structure, because the cushioning material can be reduced in volume by being pressed, a large amount of cushioning material can be loaded for transport. Furthermore, there are advantages in that the cushioning material of the present invention is stronger than and has increased shock absorption ability compared to conventional cushioning material having air caps.  
         [0067]     As described above, in the cushioning material of the present invention, porous elastic balls are provided in respective spaces, which are formed in a synthetic resin film. Thus, when the cushioning material is wound in a roll shape, the volume thereof can be reduced to ¼ by being pressed, so that a large amount of cushioning material can be loaded for transport, and a large amount of cushioning material can be stored, compared to the conventional art. Thereby, logistics costs and storage costs are reduced. Particularly, in the conventional art, the cushioning material must be stood upright when stored, but, in present invention, because the cushioning material is contained in the roll casing, it can be stored in a vertical or horizontal orientation, that is, it can be selectively oriented depending on the conditions of cargo or conditions in a transport vehicle.  
         [0068]     Although the preferred embodiments of the present invention have been disclosed for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims.