Patent Publication Number: US-2012041401-A1

Title: Minus-pressured bandage

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates generally to a medical apparatus, and more particularly, to a minus-pressured bandage. 
     2. Description of the Related Art 
     According to clinical researches, applying a minus pressure to a tissue compartment can reinforce and accelerate the growth of new tissues at this tissue compartment. In the medical field, it is called “minus-pressured therapy”, “antihypertensive therapy”, or “vacuum therapy”, which is applied to wound healing. Such therapy includes many advantages, such as healing of granulation tissues and angiogenesis. 
     Referring to  FIG. 1 , a conventional minus-pressured device includes a covering layer  81  and an absorbent layer  92 . The covering layer  91  includes two combination portions  911  formed at two opposite lateral edges thereof separately. The two combination portions  911  can be fastened with each other. The covering layer  91  includes a conduit  912  formed at a center thereof. The absorbent layer  92  is made of a porous material, like a sponge. 
     Referring to  FIG. 2  in view of  FIG. 1 , when the conventional minus-pressured device is operated, the absorbent layer  92  is laid on a user&#39;s wound first and then the covering layer  91  is put on the absorbent layer  92  and wound around the human body, like four limbs. Next, the two combination portions  911  can fasten the covering layer  91 . The conduit  912  can be connected with a minus-pressured device  93  via a duct  931  to allow the minus-pressured device  92  to decompress what the covering layer  91  covers. 
     The conventional minus-pressured device  93  can generate and apply minus-pressured suction to the wound through the porous structure of the absorbent layer  92 , such that the tissues at the wound undergo the minus-pressured suction, namely micro mechanical force, to promote capillary angiogenesis. 
     However, the absorbent layer  92  is made of the porous material which is flexible, so the absorbent layer  92  can be squeezed by the minus pressure to be deformed, while the minus-pressured device  93  decompresses what the covering layer  91  covers, to further deform the pores of the covering layer  91 . In this way, the minus-pressured suction of the pores can be adversely affected and even the pores can be occluded, thus bringing adverse influence to the micro mechanical force applied to the tissues at the wound and applying adverse influence to the capillary angiogenesis at the wound tissues. 
     SUMMARY OF THE INVENTION 
     The primary objective of the present invention is to provide a minus-pressured bandage, which can enhance the minus-pressured suction applied to the wound tissues to promote the capillary angiogenesis. 
     The secondary objective of the present invention is to provide a minus-pressured bandage, which can more perfectly fit the wound. 
     Another objective of the present invention is to provide a minus-pressured bandage, which can be trimmed according to the size of the wound. 
     The foregoing objectives of the present invention are attained by the minus-pressured bandage composed of a coverage layer, a minus-pressured acting member, an adhering layer, and a fixing tap. The minus-pressed acting member includes a fixed-shaped layer and a contact layer abutting against the fixed-shaped layer. The contact layer is made of a resilient material. The fixed-shaped layer has hardness greater than that of the contact layer. Each of the fixed-shaped layer and the contact layer has a plurality of first absorbing holes and a plurality of second absorbing holes aligned with the first absorbing holes separately. The adhering layer is porous and abuts between the coverage layer and the fixed-shaped layer. The fixing tap is mounted to the coverage layer in order to fasten the minus-pressured bandage on the wound. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an exploded view of the prior art. 
         FIG. 2  is a sectional view of the prior art. 
         FIG. 3  is an exploded view of the first preferred embodiment of the present invention. 
         FIG. 4  is a sectional view of the first preferred embodiment of the present invention. 
         FIG. 5  is a schematic view of the first preferred embodiment of the present invention at work. 
         FIG. 6  is an enlarged view of a part taken from  FIG. 5 . 
         FIG. 7  is a sectional view of a second preferred embodiment of the present invention. 
         FIG. 8  is a schematic view of the second preferred embodiment of the present invention at work. 
     
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     Referring to  FIGS. 3-4 , a minus-pressured bandage is composed of a coverage layer  1 , a minus-pressured acting member  2 , an adhering layer  3 , and a fixing tap  4 . The adhering layer  3  is mounted between the coverage layer  1  and the minus-pressured acting member  2 . The minus-pressured acting member  2  can be laid on the user&#39;s wound for minus-pressured therapy. The fixing tap  4  is mounted to the coverage layer  1  for fastening the minus-pressured bandage to the wound in such a way that the minus-pressured bandage can be prevented from disengagement or displacement with respect to the wound. The detailed descriptions and operations of these elements as well as their interrelations are recited in the respective paragraphs as follows. 
     The coverage layer  1  is made of a deformable metal or plastic; preferably, the coverage layer  1  is made of a metallic sheet, like aluminum sheet. The coverage layer  1  includes a through hole  11 . A conduit  12  is mounted to the through hole  11 . The conduit  12  has a first end protruding from the coverage layer  1  in one piece or separably. The conduit  12  has a second end provided with a check valve  13 . 
     A minus-pressured acting member  2  includes a fixed-shape layer  21  and a contact layer  22 . The fixed-shaped layer  21  is made of a deformable metal or plastic; preferably, the minus-pressured acting member  2  is made of a metallic sheet, like aluminum sheet. The contact layer  22  is made of a resilient material, which is preferably PVC or a biomedical one. The fixed-shaped layer  21  has hardness greater that of the contact layer  22 . The fixed-shaped layer  21  has a plurality of first absorbing holes  211 . The contact layer  22  has a plurality of second absorbing holes  221 . Besides, the contact layer  22  has thickness preferably greater than but at most not double as much as that of the fixed-shaped layer  21 . 
     The adhering layer  3  abuts between the coverage layer  1  and the fixed-shaped layer  21  and is made of a porous material, which is preferably a sponge. The adhering layer  3  includes a central adhering member  31  and at least one annular adhering member  32 . In this embodiment, for illustration, one central adhering member  31  and two annular adhering members  32  are taken as an example. Each of the central adhering member  31  and the annular adhering members  32  can be circular, elliptic, or rectangular. The two annular adhering members  32  have different sizes and surround the central adhering member  31 . The central adhering member  31  is located with respect to the through hole  11 . Besides, the relatively smaller adhering member  32  has an internal diameter greater than an external diameter of the central adhering member  31 , and the relatively bigger adhering member  32  has an internal diameter larger than an external diameter of the relatively smaller adhering member  32 , such that two gaps  33  are formed between one of the annular adhering members  32  and the central adhering member  31  and between the two annular adhering members  32  separately. Each of the first and second absorbing holes  211  and  221  are preferably located within the range that the central adhering member  31  abuts against the two annular adhering members  32 . 
     The fixing tap  4  is mounted to the coverage layer  1  and is composed of two conventional Velcro® (hook and loop) straps  41  in this embodiment. Each of the Velcro® straps  41  includes a first end and a second end. The first ends of the two Velcro® straps  41  are fixed to the coverage layer  1  and preferably located over the central adhering member  31 . The second ends of the Velcro® straps  41  can adhere to each other. 
     When the minus-pressured bandage is operated, external peripheral edges of the coverage layer  1  and the minus-pressured acting member  2  can be bent, abut against, and fastened to each other to form a closed space between the coverage layer  1  and the minus-pressured acting member  2 . Referring to  FIG. 5 , when the wound that the minus-pressured therapy is to be applied to is smaller, the coverage layer  1  and the minus-pressured acting member  2  can be trimmed to a proper size along one of the gaps  33  and then the external peripheral edges of the trimmed coverage layer  1  and minus-pressured acting member  2  can be bent and abut against each other; a fastener  5  (e.g. adhesive tap) can be adhesively fastened o the external peripheral edges of the trimmed coverage layer  1  and the minus-pressured acting member  2  to also form a closed space therebetween. 
     When the present invention is used, the contact layer  22  is laid on the wound. Because the coverage layer  1  and the fixed-shaped layer  21  are deformable, the minus-pressured bandage can be deformed according to the wound and its ambient human curve and fixedly shaped to perfectly fit the human body. Besides, the contact layer  22  is resilient to be deformable, so it can perfectly fit the wound tissues and ambient skin thereof. Next, the two Velcro® straps  41  can be wound around the human body to fasten the minus-pressured bandage to the wound to prevent it from disengagement or displacement. 
     Referring to  FIGS. 5-6 , the conduit  12  can be connected with a minus-pressured device  6  via a duct  61  to allow the minus-pressured device  6  to decompress the closed space between the coverage layer  1  and the minus-pressured acting member  2  and to apply minus-pressured suction to the wound through the first and second absorbing holes  211  and  221  to allow the wound tissues to undergo the minus-pressured suction in the first and second absorbing holes  211  and  221 . Because the contact layer  22  is connected to the fixed-shaped layer  21 , it is though resilient but has sufficient fixed-shape strength to prevent the second absorbing holes  221  from deformation resulting from minus-pressured squeeze to further promote capillary angiogenesis at the wound tissues. 
     Referring  FIGS. 7-8 , a minus-pressured bandage constructed according to a second embodiment of the present invention is similar to that of the first embodiment, having the following difference. The minus-pressured bandage further includes a plurality of fixing members  5 ′ mounted to internal sides of the coverage layer  1  and the fixed-shape layer  21  separately, which face each other. Each of the fixing members  5 ′ is preferably mounted to the gap  33  and can adhere to the other adjacent fixing member  5 ′. Thus, after the coverage layer  1  and the minus-pressured acting member  2  are trimmed along one of the gaps  33  according to the size of the wound that the minus-pressured therapy is to be applied, the trimmed external peripheral edges of the coverage layer  1  and the minus-pressured acting member  2  can be adhesively fastened via the fixing members  5 ′. 
     As set above, the contact layer is connected to the fixed-shape layer. The fixed-shaped layer can be a metallic sheet to enable the contact layer to have sufficient fixed-shape strength though it is resilient to prevent the second absorbing holes from deformation resulting from the minus-pressured squeeze and to enhance the minus-pressured suction applied to the wound tissues for promotion of capillary angiogenesis. 
     In conclusion, the coverage layer and the fixed-shape layer of the present invention both are deformable, so the minus-pressured bandage can be deformed according to the wound and its ambient human curve. Besides, after the minus-pressured bandage is bent, it can still be fixedly shaped to keep perfectly fitting the human body. Moreover, the coverage layer and the minus-pressured acting member can trimmed to a proper size subject to the size of the wound that the minus-pressured therapy is to be applied to. 
     Although the present invention has been described with respect to specific preferred embodiments thereof, it is in no way limited to the specifics of the illustrated structures but changes and modifications may be made within the scope of the appended claims.