US 20020037114 A1
An expansible bag comprises a bag body and two inner leaves. The bag body is made of airtight material and provides an inner chamber therein with an inlet communicating with the external atmosphere. The inner leaves are membranes attached to an inner wall of the bag body and provide two pressing stripes at a lateral side thereof respectively in a way of keeping a respective clearance path joining a part thereof to the bag body at both lateral sides of the clearance path respectively. The respective clearance path communicates with the inlet so that the bag body can be filled with fluid.
1. An expansible bag, comprising
a bag body, being made of airtight material, providing an inner chamber therein, and having an inlet communicating with an external part; and
two inner leaves, being membranes attached to an inner wall of the bag body, providing two pressing stripes at a lateral side thereof respectively in a way of keeping a respective clearance path, joining a part thereof to the bag body at both lateral sides of the clearance path respectively, and the clearance path communicating with the inlet for the bag body being filled with the fluid.
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5. The expansible bag body according to
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 1. Field of the Invention
 The present invention relates to an expansible bag, and particularly to a specific structure of an expansible bag for containing the fluid without leakage effectively.
 2. Description of Related Art
 An expansible bag has been utilized often in our daily life, and the expansible bag is used for filling with the gaseous fluid or the liquid. Due to an enlarged volume or inner space, the expansible bag can be filled with the air to form a air filled boat, a cushion pad, or an inner lining of a brassiere, can be filled with the water to form a water bag or a bra pad, or can be made as a decoration such as an aluminum foil balloon.
 The conventional expansible bag is a closed bag with an inlet and a mouthpiece, and the inlet usually is located at the same place as the mouthpiece. That is, the inlet at the entrance thereof provides the mouthpiece so as to stop the fluid in the bag moving outward. Of course, the inlet is also the outlet during the fluid being discharged.
 While the conventional expansible bag is made, it is required to break the expansible bag at a lateral side thereof before the inlet and the mouthpiece being arranged so that it not only hurts the integrity of the bag but also is unsightly to the appearance thereof because of the mouthpiece jutting out of the outer surface of the bag. Even more, it is worrisome that the conventional expansible bag is unsafe, especially, with regard to the problem of leakage.
 Taking the expansible bag used in the brassiere as an example, a filling mouth for the gaseous fluid or the liquid usually juts outward a certain length from the bag body such that it is harmful to the subsequent working of the bag and the integrity of the finished product. A good-looking product is a primary purpose pursued by women so that it is essential to improve the inlet and the mouthpiece.
 An object of the present invention is to provide an expansible bag, which has an airtight bag body with an inlet and two inner leaves attached to the inner wall of the bag body and two pressing stripes at a lateral side of the bag are formed to provide a clearance path respectively communicating with the inlet for performing a function of leakage proof and offering an integrity appearance.
 Referring to FIGS. 1 to 3, an expansible bag of the present invention basically comprises a bag body 1, and two inner leaves 2 so as to be filled with the gaseous fluid or the liquid.
 Wherein, the bag body 1 is made of airtight material such as the high molecular membrane and the bag body 1 illustrated in the figures is that two identical high molecular membranes are lapped over each other and the periphery edges thereof are heated up to join together such that an inner chamber 11 is formed with a bag inlet 12 at the periphery edge to communicate with the inner chamber 11.
 The inner leaves 2 also can be made of the preceding molecular membrane but it is not required. Both of the inner leaves 2 are identical in the shapes thereof and are welded together by way of the heat at a spot near the periphery thereof so as to form two pressing stripes 21 So that the inner leaves 2 can connect with each other and two clearance paths 22 are formed between the pressing stripes 21. The clearance paths 22 communicate with the bag inlet 12. In fact, the clearance paths 22 at both lateral sides of the ends thereof have a leaf wing 23 respectively to lap over an outer edge part of the bag inlet 12 and to be thermo-joined together. While the bag of the present invention is fabricated, one of the two inner leaves 2, which have pressed with the two clearance paths 22, is welded to the bag body 1 first, and then the bag body 1 is lapped over another inner leaf 2 to complete the welding around the bag body 1. It is noted that the clearance paths 22 between the two inner leaves, as shown in the figures, at least have a section identical with the bag inlet 12.
 In order to give a handy insertion during the bag body being filled with the fluid, the leaf wing 21 of each inner leaf 23 may project outward relative to the bag body 1 such that a micro difference in length between ends of the clearance paths 22 of the two inner leaves 2.
 Referring to the figures again, when the bag of the present invention is in use, a tube can be utilized to pass through the clearance path 22 and the fluid can be filled in the chamber 11 through a clearance of the respective inner leaf 2 via the tube. Then, the tube is withdrawn and the pressure of the fluid urges the two inner leaves to lap over each other tightly and to attach to the inner wall of the bag body 1. In this way, the fluid can keep the bag body 1 in a state of expansion without overflowing the fluid. In case of the fluid being discharged, the tube is inserted into the bag to pass over the two inner leaves from the clearance paths 22 again, the fluid in the bag can be released and the bag can restore to the original flat shape.
 It is appreciated from the foregoing that the present invention offers the following advantages:
 (1) The two inner leaves are disposed in the bag body so that the appearance of the bag can keep a neat shape for being helpful for the subsequent use.
 (2) The inner leaves act as valve diaphragms and it is safe and reliable so that no leakage can occur. Especially, the fluid has to pass through a passage between the two inner leaves before reaching the inlet via the clearance paths such that a function of checking can be performed. Thus, no fluid is possible to leak out easily and the filled fluid can be kept without change.
 While the invention has been described with reference to a preferred embodiment thereof, it is to be understood that modifications or variations may be easily made without departing from the spirit of this invention, which is defined in the appended claims.
 The present invention can be more fully understood by referencing to the following description and accompanying drawings, in which:
FIG. 1 is a perspective view of an expansible bag according to the present invention before filling with the fluid;
FIG. 2 is a sectional view of an inlet of the expansible bag according to the present invention; and
FIG. 3 is a perspective view of an expansible bag according to the present invention after filling with the fluid.