Patent Publication Number: US-2004057636-A1

Title: Compactor bag with a check valve

Description:
TECHNICAL FIELD  
       [0001] The present invention relates to a compactor bag, and more particularly to a bag which extracts air from the inside of the bag body for compacting of clothing, bedding, etc.  
       BACKGROUND OF THE INVENTION  
       [0002] There have been conventionally provided various kinds of bags with check valves which are used for compacting of clothing. For example, a compactor bag as shown by FIG. 17(A) is known. The bag has a zipper  3  on one side of a bag body  1  made of a resin film, and this side serves as an opening  2  for put-in and take-out of clothing. The bag further has a check valve  4  made of a pair of films and an air release path on the opposite side of the bag body  1 .  
       [0003] When this bag is used, clothing is put in the bag body  1 , and the zipper  3  is closed. Thereafter, as FIG. 17(B) shows, as the user is rolling the bag body  1 , the internal pressure of the bag body  1  rises, and air is exhausted from the bag body  1  through the check valve  4  and the air release path  5  as indicated by arrow “a”. After the air exhaustion, the pressure inside the bag body  1  decreases, and the films of the check valve  4  stick together tight. Thereby, the inside of the bag body  1  can be kept airtight.  
       [0004] In this bag, the check valve  4  and the air release path  5  are provided on one side of the bag body in a portion with a width b, and this portion with the width b cannot be used as a space for packing. Therefore, the packing efficiency is bad.  
       [0005] An object of the present invention is, therefore, to provide a compactor bag with a good packing efficiency and with a good compacting efficiency.  
       [0006] Another object of the present invention is to provide a compactor bag which has a check valve of a simple structure and which can be produced easily.  
       DISCLOSURE OF THE INVENTION  
       [0007] In order to attain the objects above, a compactor bag according to the present invention comprises a substantially rectangular bag body made of a synthetic resin film, the bag body having an openable side provided with a zipper through which an item can be put into and taken out of the bag body, said compactor bag comprising a check valve portion which is located in a right-triangular area on at least one corner of a side opposite the openable side of the bag body. In the compactor bag, the check valve portion comprises a flat and closable air release path which is formed by fused sides crossing at a right angle and a partly fused portion of films located in the right-triangular area, air inside the bag body being guided into the air release path by a hypotenuse of the right-triangular area and being exhausted, and the check valve portion communicates with a packing space of the bag body at the hypotenuse of the right-triangular area.  
       [0008] After an item such as clothing is put in the compactor bag of the above structure, the bag is rolled with the openable side inside. In the meantime, the internal pressure of the bag body rises, and air inside the bag body is guided into the air release path by the hypotenuse of the right-triangular area and is exhausted. After the air exhaustion, the internal pressure of the bag body reduces, and the films exposed to the air release path adhere together, whereby the inside of the bag body can be kept airtight. The right-triangular check valve portion which is flat and small is influenced irregularly by the packing space which contains an item and which has gain a thickness, and thereby, the check valve portion curls or bends indispensably. Because of the curl or bend, the films of the air release path certainly adhere to each other, whereby the airtightness of the bag body can be guaranteed.  
       [0009] Because air inside the bag body can be exhausted through a check valve portion which is provided on at least one corner of the bag body, it is not necessary to form an air release path outside the check valve portion. Therefore, the inside of the bag body can be used effectively as a packing space for clothing or other items.  
       [0010] When rolling the bag body with the openable side inside, air is apt to be left at the corners of the side opposite the openable side. In the compactor bag according to the present invention, however, because the check valve used for air exhaustion is provided at a corner of the side opposite the openable side, almost all of the air can be ejected out from the bag body. Thus, the compactor bag is good in air exhaustion/compacting efficiency.  
       [0011] The compactor bag according to the present invention preferably has two check valve portions at two corners of the side opposite the openable side of the bag body. By providing two check valve portions, the air exhaustion/compacting efficiency is improved.  
       [0012] The check valve portion(s) may be formed of the mutually facing surfaces of the synthetic resin film forming the bag body. In this case, since the check valve portion(s) is/are structured of the synthetic resin film of the bag body, the structure of the check valve portion(s) is easy, and manufacture of such bags is easy. It is preferred to use a soft material as the synthetic resin film for the bag body and the check valve portion(s).  
       [0013] Alternatively, the check valve portion(s) may be formed of a thin synthetic resin film which is inserted in the synthetic resin film of the bag body. By using a thin film as the material of the check valve(s), the sealing performance of the check valve(s) after air exhaustion is improved.  
       [0014] The compactor bag according to the present invention can be used to pack not only clothing and bedding but also other voluminous items such as vegetables, etc. 
     
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
     [0015]FIG. 1 show a compactor bag which is a first embodiment of the first invention,  1 (A) being a perspective view thereof and  1 (B) showing air exhaustion from the bag.  
     [0016]FIG. 2 is a plan view of the compactor bag of the first embodiment;  
     [0017]FIG. 3 is an enlarged sectional view of an openable side of the compactor bag of the first embodiment.  
     [0018]FIG. 4 is an illustration showing a process of manufacturing compactor bags of the first embodiment.  
     [0019] FIGS.  5 (A) through  5 (D) show modified check valve portions for the compactor bag of the first embodiment.  
     [0020]FIG. 6 is a plan view of a compactor bag which is a second embodiment of the present invention.  
     [0021]FIG. 7 is an enlarged plan view of a check valve of the compactor bag of the second embodiment.  
     [0022]FIG. 8 is an enlarged sectional view taken along the line X—X in FIG. 7.  
     [0023]FIG. 9 is a plan view of a check valve of the compactor bag of the second embodiment.  
     [0024]FIG. 10 is an illustration showing manufacturing processes of compactor bags of the second embodiment.  
     [0025]FIG. 11 is a front view of check valves which are used in the manufacturing processes of the compactor bags of the second embodiment.  
     [0026]FIG. 12 shows a compactor bag which is a third embodiment of the present invention,  12 (A) being a plan view and  12 (B) being a sectional view taken along the line P—P in (A).  
     [0027]FIG. 13 is an illustration showing manufacturing processes of compactor bags of the third embodiment.  
     [0028]FIG. 14 is a sectional view of the compactor bag taken along the line Y—Y in FIG. 13.  
     [0029]FIG. 15 is a sectional view of the compactor bag taken along the line Z—Z in FIG. 13.  
     [0030]FIG. 16 is an enlarged view of a portion Q in FIG. 13.  
     [0031] FIGS.  17 (A) and  17 (B) show a conventional compactor bag.  
    
    
     BEST MODE FOR CARRYING OUT THE INVENTION  
     [0032] Some embodiments of a compactor bag according to the present invention will be described with reference to the accompanying drawings.  
     [0033] First Embodiment  
     [0034] See FIGS.  1  Through  4   
     [0035] As FIGS.  1 (A),  1 (B) and  2  show, a compactor bag  10 A which is a first embodiment of the present invention has a substantially rectangular bag body  11  which is formed by stacking two synthetic resin films  12  and  13 . The bag body  11  has three fused sides (hatched portions f and g in the drawings) and an open side  14  for put-in and take-out of clothing or the like.  
     [0036] At the open side  14 , as FIG. 3 shows, a zipper  15  with a groove  17  and a ridge  18  is fused with the inner surfaces of the resin films  12  and  13 . The zipper  15  is of a conventional type which is formed by extrusion-molding the groove  17  and the ridge  18  on respective bases  16  integrally. However, the zipper  15  may be of any structure and of any shape, and the zipper  15  may be formed by extrusion-molding together with the films  12  and  13 . Also, in order to improve the airtightness of the bag body  11 , two zippers may be provided. In order to facilitate open/close motion of the zipper  15 , a slider may be provided.  
     [0037] The films  12  and  13  of the bag body  11  are preferably laminate films. As FIG. 3 shows, a fusible material such as polyethylene, polypropylene or the like is used as an inner sheets  12   a  and  13   a  of the films  12  and  13 , and polyamide, polyethylene terephthalate or the like is used as an outer sheets  12   b  and  13   b  of the films  12  and  13 .  
     [0038] A feature of this compactor bag  10 A is to have check valve portions  20  in right-triangular areas at the corners which are opposite the open side  14  of the bag body  11 . As FIG. 2 shows, each of the check valves  20  comprises the fused portions f and g which are the sides forming the right angle and an air release path  22  made in a triangular fused portion  21 . Air inside the bag body  11  is guided by the triangular fused portion and is exhausted through an non-fused portion g′ as shown by arrow “d”.  
     [0039] The entire inside of the bag body  11  except the check valve portions  20  can be used as a packing space for clothing or the like, and the check valve portions  20  directly communicate with the packing space at the triangular fused portions.  
     [0040] When the compactor bag  10 A of the above structure is used, the zipper  15  is opened, and clothing is put inside through the open side  14 . Thereafter, the zipper  15  is closed, and the bag body  11  is rolled up in such a way the openable side  14  will be rolled inside (see FIG. 1(B)). In the meantime, the internal pressure of the bag body  11  rises, and air inside the bag body  11  is exhausted through the air release paths  22  of the check valve portions  20  (see arrow “d”). The air exhaustion is completed when the clothing in the bag body  11  is compressed. Once air exhaustion has been carried out, the internal pressure of the bag body  11  decreases, and the respective inner surfaces of the films  12  and  13  in the air release paths  22  stick together. Thereby, air is prevented from flowing back into the bag body  11 , and the inside of the bag body  11  is kept airtight.  
     [0041] The air exhausting performance and the sealing performance of the check valve portions  20  depend on the width and the length of the air release paths  22  and the adherence of the films  12  and  13  to each other. More specifically, if the air release paths  22  are wide, short and straight, the air exhausting performance of the check valve portions  20  is good. On the other hand, if the air release paths  22  are narrow, long and curved, the sealing performance (effect of preventing air from flowing backward) of the check valve portions  20  is good. The effect of preventing air from flowing backward is brought by adherence of the films  12  and  13  to each other. If the films bend or curl, the films adhere to each other at the bending or curling portion, whereby an air flow is cut at the portion. Providing narrow and/or long air release paths  22  heightens the certainty of adherence of the films  12  and  13  to each other but lowers the air exhausting performance.  
     [0042] Therefore, the best check valve portions  20  are to have air release paths  22  which are straight while exhausting air and which curl after air exhaustion. In the bag body  11 , each of the check valve portions  20  is formed at a corner of the bag body  11  to have the shape of a right triangle. The right-triangular check valve portions  20  take in air with the hypotenuses guiding air, and the hypotenuses communicate with the packing space of the bag body  11 . In this structure, during air exhaustion, the air release paths  22  keep straight in parallel to the planes of the films  12  and  13  because of an increase in internal pressure, and after air exhaustion, the air release paths  22  curl or bend around the hypotenuses or the flat portions. Thus, the check valve portions  20  are good both in air exhausting performance and in sealing performance. A right triangle is an ideal shape to provide an air release path  22  therein, and the hypotenuse is an ideal spot to locate the inlet of the air release path  22  thereat.  
     [0043] Also, in the bag body  11 , clothing or the like can be also put in the space E shown in FIG. 2, and the packing efficiency is better than that of a conventional bag.  
     [0044] When the bag body  11  is rolled with the openable side  14  inside, because of the fused portions f and g, air is collected at the corners F (see FIG. 1(B)) on the opposite side of the openable side  14 . In the bag body  11 , since the check valve portions  20  are provided at the corners F where the collected air heightens the internal pressure, almost all of the air collected at the corners F can be ejected. Thus, the air exhaustion/compacting efficiency is good.  
     [0045] Next, manufacturing processes of such compactor bags  10 A are described with reference to FIG. 4.  
     [0046] In the first process, while the films  12  and  13  are unrolled and stacked one upon the other, the zipper  15  is provided between the films  12  and  13  by fusion, and the films  12  and  13  are fused by a horizontal heater at a bottom side (fused portion f). Next, in the second process, the films  12  and  13  are fused together by a vertical heating bar to make a fused vertical side (fused portion g). The vertical heating bar comprises a heating section for forming the check valve portions  20 , and simultaneously with the fusion at the side, the fused portions  21  of the check valve portions  20  are made. Thereby, the air release paths  22  are formed.  
     [0047] Thereafter, in the third process, the films  12  and  13  are cut at the center of the fused side g. Thus, the compactor bag  10 A is produced. One bag body  11  may have one check valve portion  20  at one corner; however, even in a case of forming two check valve portions  20  at both corners, the number of fusing processes at the vertical side g is only one. Modifications of the Check Valve Portions; See FIGS.  5 (A) through  5 (D)  
     [0048] In the compactor bag  10 A of the first embodiment, the check valve portions  20  may be of any of various other shapes. FIGS.  5 (A) through  5 (D) show some exemplary shapes. The shape and the size of the air release paths  22  are designed arbitrarily according to the volume of air exhaustion.  
     [0049] The check valve portion  20  shown by FIG. 5(A) has fused portions  21  at a corner of the bag body  11 , and thereby, a straight air release path  22  is formed between the fused portions  21 . Further, a fused portion  23  which serves as a weir is made on the hypotenuse of the right triangle. The route of air exhausted through this check valve portion  20  is indicated by arrow “d”. The vertex of the corner of the bag body  11  where this check valve portion  20  is located is cut off.  
     [0050] The check valve portion  20  shown by FIG. 5(B) has an air release path  22  which extend among islands of fused portions  24 . The route of air exhausted through this check valve portion  20  is indicated by arrow “d”. In the case of FIG. 5(B), the air release path  22  has two outlets (non-fused portions) f and g′.  
     [0051] The check valve portion  20  shown by FIG. 5(C) has islands of fused portions  25  and slits  26  made in the films  12  and  13 , and an air release path  22  is formed between the slits  26 . The route of air exhausted through this check valve portion  20  is indicated by arrow “d”. Further, a fused portion  25 ′ is formed to prevent clothing or other items put in the bag body  11  from closing the air release path  22  and to keep adherence of the films  12  and  13  to each other.  
     [0052] The check valve portion  20  shown by FIG. 5(D) has a fused portion  27  and an air release path  22  extending along the fused portion f. The route of air exhausted through this check valve portion  20  is indicated by arrow “d”. Further, a fused portion  25 ′ is formed to prevent clothing or other items put in the bag body  11  from closing the air release path  22  and to keep adherence of the films  12  and  13  to each other.  
     [0053] In the above-described modifications, the fused portions  23 ,  24 ,  25 ,  25 ′ and  27  are made by fusing the films  12  and  13  with each other.  
     Second Embodiment  
     [0054] See FIGS.  6  Through  11   
     [0055]FIG. 6 shows a compactor bag  10 B which is a second embodiment of the present invention. In the compactor bag  10 B, check valves  30 , each of which is composed of two synthetic resin films, are provided instead of the check valve portions  20  in the first embodiment. The check valves  30  are located at both corners on the side opposite the openable side  14  of the bag body  11 . The other parts are the same as those of the first embodiment. These parts are provided with the same reference symbols, and a repetition of a description thereof is omitted.  
     [0056] Each of the check valves  30 , as shown by FIGS. 7, 8 and  9 , are made by fusing two fusible thin and soft films  31  and  32  (for example, polyethylene films) with each other at a portion h. Also, each of the check valves  30  has fused branch portions  34  and a hole  35  which pierces also through the front and back sides of the bag body  11 , and thereby, an air release path  33  is formed. The route of air exhausted through this air release path  33  is indicated by arrow “d”.  
     [0057] Further, the check valves  30  are fixed to the bag body  11  by fused portions f and g. The hatched portion i in FIG. 7 indicates a portion where the inner surfaces of the films  12  and  13  of the bag body  11  are fused respectively with the films  31  and  32  of the check valve  30 . This fused portion i is to prevent air leakage. The mutually facing surfaces of the films  31  and  32  had been subjected to a fusion preventing treatment, for example, had been coated with ink  36  so that the mutually facing surfaces of the films  31  and  32  would not be fused together when the fused portion i was formed.  
     [0058] The compactor bag  10 B of the above structure can be used in the same way as the compactor bag of the first embodiment, and the bag  10 B has the same effect as the bag of the first embodiment. In the second embodiment, especially because thin and soft films  31  and  32  are used for the check valves  30 , the check valves  30  have a strong effect of preventing air from flowing backward (effect of maintaining airtightness) after air exhaustion.  
     [0059] Next, manufacturing processes of such compactor bags  10 B are described with reference to FIGS. 10 and 11.  
     [0060] First, referring to FIG. 10, while films  12  and  13  are unrolled, the films  12  and  13  are stacked one upon the other with the zipper  15  and the check valves  30  inserted in-between. The check valves  30  are fused between the films  12  and  13  at the fused portions i in this first process.  
     [0061] The check valves  30  used in this first process are cut sequentially from a series of check valves  30 ′. As FIG. 11 shows, the series of check valves  30 ′ is a serial connection of pairs of check valves  30 . In each pair, two check valves  30  are joined back to back, and these check valves  30  are to be cut from each other later. The series of check valves  30 ′ is made by fusing the films  31  and  32  at portions h and  34  so as to form the air release paths  33  in the respective check valves  30  and further by coating fusion preventing ink  36  on the mutually facing surfaces of the films  31  and  32 . The check valves are cut from the series of check valves  30 ′ at lines j pair by pair, and in the first process, these pairs of check valves  30  are inserted and fused between the films  12  and  13  sequentially.  
     [0062] Next, in the second process, the zipper  15  is fused with the films  12  and  13  by use of a heating bar  51 , and further, the films  12  and  13  of the bag body  11  are fused together at a side f by use of a heating bar  52 . The fusion at the side f is also to fuse the films  31  and  32  of the check valves  30  with the films  12  and  13  of the bag body  11 .  
     [0063] Thereafter, in the third process, the films  11  and  12  are fused together at a vertical side g by use of a vertically positioned heating bar (not shown). Simultaneously, through holes  35  for air exhaustion are made. Then, in the fourth process, the films  12  and  13  are cut at the center of the fused vertical side g, and thereby, a compactor bag  10 B is cut off. Thus, compactor bags  10 B of the above structure can be manufactured.  
     [0064] In the second embodiment, instead of the fused branch portions  34 , fused islands as shown in FIG. 5 may be formed. Also, the holes  35  may be replaced with slits.  
     Third Embodiment  
     [0065] See FIGS.  12 (A) and  12 (B) Through  16   
     [0066] As FIG. 12(A) shows, a compactor bag  10 C which is a third embodiment of the present invention has check valves  40  instead of the check valves  30  of the second embodiment. The check valves  40  are formed by inserting two synthetic resin films  41  and  42  between the films  12  and  13  along the side opposite the openable side  14  entirely from an end to the other end.  
     [0067] The four films  12 ,  13 ,  41  and  42  are fused together at portions f and g. At a portion k, as FIG. 12(B) shows, the film  12  is fused with the film  41 , and the film  13  is fused with the film  42 . At this portion k, the films  41  and  42  are not fused together.  
     [0068] In the check valves  40 , as in the first embodiment, air release paths  43  are formed between fused branch portions  44  (which may be islands). The formation of the fused portions  44  is carried out simultaneously with the fusion of the films  12 ,  13 ,  41  and  42  at the sides g. The portions g′ of the sides g are non-fused portions serving as outlets of the air release paths  43 . To the air release paths  43  indicated by arrow “d”, only the thin and soft films  41  and  42  (for example, polyethylene films) are exposed. The outlets of the air release paths  43  may be positioned at portions of the side f.  
     [0069] The followings are the purposes of forming the fused portion k. Because the films  41  and  42  are fused respectively with the inner surfaces of the films  12  and  13 , when clothing or any other item is put in the bag  10 C through the open side  14 , the films  41  and  42  will never obstruct the item to be packed. Also, air is prevented from coming into the bag  10 C from the outlets (non-fused portions g′) through the space between the films  12  and  41  and the space between the films  13  and  42 .  
     [0070] The compactor bag  10 C of the above structure can be used in the same way and has the same effect as those of the first and second embodiments. In the third embodiment, because long films  41  and  42  are used for the check valves  40 , it is not necessary to prepare a series of check valves  30 ′ as in the second embodiment.  
     [0071] Next, referring to FIGS. 13 through 16, manufacturing processes of such compactor bags  10 C are described.  
     [0072] Referring to FIG. 13, in the first process, while films  12  and  13  are unrolled, the films  12  and  13  are stacked one upon the other with the zipper  15  and the films  41  and  42  inserted in-between (see FIG. 14).  
     [0073] Next, in the second process, the zipper  15  is fused with the films  12  and  13  by use of a heating bar  51 , and the films  41  and  42  are fused respectively with the films  12  and  13  at the portion k by use of a heating bar  53 . In carrying out the fusion at the portion k, a fusion preventing plate  54  is inserted between the films  41  and  42  (see FIG. 15) so that the films  41  and  42  will not fuse with each other. It is possible to coat fusion preventing ink  36  on the mutually facing surfaces of the films  41  and  42  as is carried out in the second embodiment, instead of inserting the plate  54 .  
     [0074] In the third process, the films  12  and  13  are fused together at a side f, whereby the fused bottom side f of the bag body  11  is made. This fusing process at the side f is also to fuse the films  41  and  42  of the check valves  40  with the films  12  and  13 .  
     [0075] Thereafter, in the fourth process, the films are fused together at a vertical side g by use of a vertically positioned heating bar (not shown). Simultaneously, the fused branch portions  44  of the check valves  40  are formed, and the air release paths  43  and their outlets (non-fused portions g′) are made (see FIG. 16). Then, in the fifth process, the films  12  and  13  are cut at the center of the vertical fused portion g, and thereby, a compactor bag  10 C is cut off. Thus, compactor bags  10 C of the above structure can be manufactured.  
     Other Embodiments  
     [0076] Compactor bags according to the present invention are not limited to the above embodiments, and various changes and modifications are possible within the scope of the invention.  
     [0077] Various kinds of resin can be used for the films  12 ,  13 ,  31 ,  32 ,  41  and  42 . The detailed structures and shapes of the check valve portions  20 , and the check valves  30  and  40  can be designed arbitrarily.  
     [0078] In the third embodiment, the check valves  40  are made of two films which are stacked one upon the other; however, the check valves  40  may be made by inserting a single film between the films  12  and  13  of the bag body  11 .  
     [0079] The manufacturing processes of the first, second and third embodiments include a process of fusing the zipper  15  with the films  12  and  13 . It is, however, possible to use a film with the zipper fitted thereto beforehand and to manufacture compactor bags by meltdown. In this case, the portion f is not a fused portion but a fold portion. Also, the bag body  11  may be structured into a gazette bag, and the check valve portion  20 , or the check valves  30  or  40  may be provided thereto.  
     [0080] Further, the check valve portions  20 , and the check valves  39  and  40  can be provided for vacuum compactor bags from which air is extracted by a vacuum cleaner or the like.  
     Industrial Applicability  
     [0081] As has been described, compactor bags according to the present invention are good in air exhaustion efficiency and in compacting efficiency. These bags are suited for compacting of clothing which permits easy carriage of the clothing.