backpack

Abstract

To provide a backpack bag which can be moved between the rear and front of the body without putting the bag body down on the ground or floor, and which is easy to operate, practical and looks good. [Solution] The backpack bag according to the present disclosure has an auxiliary shoulder strap 5 in addition to a pair of left and right main shoulder straps 3, 4 connected to the bag body 1. A base end 8 of the auxiliary shoulder strap 5 connects to the shoulder portion of the main shoulder strap 3, and a tip 10 is connected to a fastener 9A. A detachable fastener 9B is connected to the fastener 9A at the front of the shoulder of the main shoulder strap 3. Another detachable fastener 9C is connected to the fastener 9A at the waist portion of the main shoulder strap 4. When the bag body 1 is carried behind the body, the auxiliary shoulder strap 5 can be aligned with the main shoulder strap 3 by attaching the fastener 9A to the fastener 9B. By attaching the fastener 9A to the fastener 9C, the auxiliary shoulder strap 5 can be configured as a shoulder strap worn diagonally across the body, allowing the bag body 1 to be moved from behind the body to the front.

Description

[Technical Field]

[0001] The present invention relates to a backpack bag, and more particularly to a technique that enables the bag body to be moved between the rear and front of the body without being placed on the ground or floor. [Background technology]

[0002] In recent years, the number of people using backpacks and other on-the-back bags for commuting and other purposes has increased, and when boarding the train, it is common to see people shifting their bags in front of their chests to avoid disturbing other passengers. However, shifting a bag that is quite heavy and large back onto their backs is quite laborious. When it is difficult to shift the bag forward, it is common to see people placing it on the floor.

[0003] Various backpacks have been proposed to solve this problem (Patent Documents 1 to 12). However, all of them lack operability, practicality, or aesthetic appeal. For example, in Patent Document 1, the storage section 4 (bag body) is supported by a sliding section 5 that allows the guide section 3 to slide, and the storage section 4 can be moved between the front and back of the body by sliding along the guide section 3. To ensure stable support, the storage section 4 is removably supported by fasteners 7 and 8. However, in addition to the need for labor to removably support the storage section 4 by the fasteners 7 and 8, there are problems with the appearance being unattractive because the guide section 3 is always exposed to the left or right side of the body.

[0004] In Patent Document 2, the lower ends of the pair of main belts are detachable, and one of the pair of main belts can be worn cross-body, so that by wearing the cross-body main belt over the shoulder, the bag can be moved from the back to the front of the body without dropping the bag to the ground. However, after moving the bag, it is not easy to put the cross-body main belt back on, which is a problem in terms of operability.

[0005] In Patent Document 3, when joining portions 30A and 30B are separated, joining portions 40A and 40B are separated, and joining portions 50A and 50B are connected, there is a risk that the neck may be subjected to a load from belts 20A and 20B. In addition, the method of supporting the bag body is unstable, and there is a problem that it is not very practical.

[0006] In Patent Document 4, three main belts are provided, two of which are used, and the bag body can be repositioned by replacing one of the used belts with the other unused one. However, there is a problem in that the unused main belt always hangs down, which makes it look unattractive.

[0007] In Patent Document 5, a pair of main belts are worn in reverse between the front and back, so the bag body can be moved back and forth without having to switch the main belts between the left and right shoulders. However, since the main belts are always worn in a cross-body position, there is a problem that it is not very practical because it puts pressure on the neck.

[0008] In Patent Document 6, the bag portion 10 (bag body) is configured to be moved between front and rear over the head. When the bag body contains a lot of items and is heavy, such operation is not easy, and there is a problem that it is not suitable for operation on a train in particular.

[0009] In Patent Document 7, an auxiliary belt is provided in addition to two main belts. By removing the two main belts from the shoulders and suspending the bag body using only the auxiliary belts, the bag body can be moved from the back to the front of the body without dropping to the ground. However, even when carrying the bag body on the back, it is necessary to hang the auxiliary belt on the shoulders in addition to the two main belts, which causes a problem of poor operability.

[0010] In Patent Document 8, the pair of main belts are detachably separated midway, allowing the bag body 1 to be supported by the elastic belt 41, thereby allowing the bag body 1 to be moved forward. However, there is a problem in that it is not easy to reconnect the pair of separated main belts after the bag body 1 has been moved forward. On the other hand, if the bag body 1 is constantly supported forward only by the elastic belt 41 without connecting the pair of main belts, the pair of separated main belts will hang down, which creates an unattractive appearance.

[0011] In Patent Document 9, one of a pair of main belts can be lengthened switchably, and the bag body 1 can be moved forward while the other main belt supports the bag body. However, there is a problem in that it is not easy to shorten the main belt that has been lengthened.

[0012] In Patent Document 10, a pair of shoulder straps are connected to form a ring and slidably supported on the bag body, allowing the bag body to be tilted to either the left or right of the ring-shaped shoulder straps, thereby allowing the bag body to be moved forward or backward. However, because the bag body can slide on the shoulder straps, the position of the bag body when worn backward or forward is unstable, which is a problem and makes it less practical.

[0013] In Patent Document 11, a zipper is provided on one of a pair of main belts, and by opening and closing the zipper, the length of the main belt can be extended or returned, thereby making it possible to move the bag body back and forth. However, there was a problem in that the zipper drooped, which made it look unattractive, and in particular, when the zipper was opened, one side of the open zipper drooped, which made it look particularly unattractive.

[0014] In Patent Document 12, a pair of main belts can be separated midway. A chest belt is also provided to connect the pair of main belts, and this chest belt can also be separated midway. By separating one of the main belts, the bag body can be carried by the other main belt and the chest belt, allowing the user to move forward and backward while carrying the bag body. However, the configuration is similar to Patent Document 3, and the same problems as Patent Document 3 exist. [Prior art documents] [Patent documents]

[0015] [Patent Document 1] Patent No. 6875618 [Patent Document 2] Patent No. 7503350 [Patent Document 3] Publication No. 3235444 [Patent Document 4] Patent No. 6908813 [Patent Document 5] Japanese Patent Publication No. 2020-130823 [Patent Document 6] Patent No. 6829122 [Patent Document 7] Publication No. 3162559 [Patent Document 8] Publication No. 3110920 [Patent Document 9] Patent No. 3432186 [Patent Document 10] Japanese Patent Application Publication No. 11-164734 [Patent Document 11] Japanese Patent Application Publication No. 10-313942 [Patent Document 12] Publication No. 3026143 Summary of the Invention [Problem to be solved by the invention]

[0016] The present invention has been made in consideration of the above problems, and aims to provide a backpack that can be moved between the front and back of the body without having to be put down on the ground or floor, and that is easy to operate, practical, and looks good. [Means for solving the problem]

[0017] To achieve the above object, a first aspect of the present invention provides a backpack bag comprising a bag body (1), a pair of left and right main shoulder straps (3, 4), and an auxiliary shoulder strap (5). The bag body (1) is used to carry an object. The pair of left and right main shoulder straps (3, 4) are connected to the bag body (1) and allow the bag body (1) to be worn over the left and right shoulders. The auxiliary shoulder strap (5) has a base end (8) connected to a portion (15, 17) of the bag body (1) near the upper end (31) of one of the pair of main shoulder straps (3, 4) or to the shoulder portion of the one main shoulder strap (3), and one (9A) of two detachable fasteners (9) is connected to the tip (10) of the auxiliary shoulder strap (5). The backpack bag according to the first aspect further includes a first other end (9B) of the fastener (9) and a second other end (9C) of the fastener (9). The first other end (9B) of the fastener (9) is connected to one of the main shoulder straps (3) so as to be located in the front portion of the shoulder of the one of the main shoulder straps (3). The second other end (9C) of the fastener (9) is connected to a portion (11, 18) of the bag body (1) near the lower end (43) of the other main shoulder strap (4) or to the waist portion of the other main shoulder strap (4) so ​​as to be located in the waist portion near the other of the pair of main shoulder straps (3, 4). The auxiliary shoulder strap (5) forms a cross-body shoulder strap when the first end (9A) of the fastener (9) is attached to the second other end (9C) of the fastener (9).

[0018] With this configuration, when carrying the bag behind the body, one of the fasteners connected to the tip of the auxiliary shoulder strap can be attached to the first other fastener, allowing the auxiliary shoulder strap to be aligned with one of the main shoulder straps. This prevents the auxiliary shoulder strap from appearing unnatural to onlookers and detracts from the attractive appearance of the backpack. When moving the bag from the back to the front of the body, one of the fasteners connected to the tip of the auxiliary shoulder strap can be attached to the second other fastener, allowing the auxiliary shoulder strap to be worn diagonally across the body (cross-body). This allows the bag to be carried by the auxiliary shoulder straps, so that while still carrying the bag, the user can remove the pair of main shoulder straps from their shoulders, move the bag from back to front, and place the pair of main shoulder straps on the opposite shoulder. In other words, the bag can be moved from back to front without dropping it on the floor or the like. By reversing the procedure, the bag body can be returned from the front to the rear without having to lower it to the floor, etc. These operations are simple and do not require any special effort. In this invention, the term "shoulder strap" is used to include a belt-like structure either partially or entirely. Furthermore, the term "connection" in relation to a "fastener" is used to mean both a direct connection and an indirect connection via a string or the like. Although the components of the present invention are given reference numerals in the drawings, this is merely an example, and is not intended to limit the present invention to these examples, as there are many elements involved. The same applies to the reference numerals in the drawings used in the claims.

[0019] To achieve the above object, a second aspect of the present invention provides a backpack bag comprising a bag body (1), a pair of left and right main shoulder straps (3, 4), and one (21A) of first fasteners (21). The bag body (1) is for carrying an object. The pair of left and right main shoulder straps (3, 4) are connected to the bag body (1) and allow the bag body (1) to be worn on the left or right shoulder. The one (21A) of the first fasteners (21) is connected to a portion (15, 17) of the bag body (1) near the upper end (31) of one of the pair of main shoulder straps (3, 4) so ​​as to be located at the shoulder portion of the one of the pair of main shoulder straps (3, 4), or to the shoulder portion of the one of the pair of main shoulder straps (3), and is detachable from each other. The backpack bag according to the second aspect further includes a first other (9B) of the second fastener (9) detachable from one (9A) of the second fastener (9), and a second other (9C) of the second fastener (9) detachable from the one (9A) of the second fastener (9). The first other (9B) of the second fastener (9) is connected to one of the main shoulder straps (3) so as to be located in the front portion of the shoulder of the one of the main shoulder straps (3). The second other (9C) of the second fastener (9) is connected to a portion (11, 18) of the bag body (1) near the lower end (43) of the other main shoulder strap (4) or to the waist portion of the other main shoulder strap (4) so ​​as to be located in the waist portion near the other main shoulder strap (4) of the pair of main shoulder straps (3, 4).

[0020] According to this configuration, by adding an auxiliary shoulder strap of an appropriate length, with the other end of the first fastener connected to the base end and one end of the second fastener connected to the tip end, and attaching one end of the first fastener to the other end, a backpack bag according to the first embodiment is completed.

[0021] A third aspect of the present invention is the backpack bag of the second aspect, further comprising an auxiliary shoulder strap (5) having the other end (21B) of the first fastener (21) connected to the base end (8) and the one end (9A) of the second fastener (9) connected to the tip end (10). The auxiliary shoulder strap (5) forms a shoulder strap for hanging across the body when the other end (21B) of the first fastener (21) is attached to the one end (21A) of the first fastener (21) and the one end (9A) of the second fastener (9) is attached to the second other end (9C) of the second fastener (9).

[0022] This configuration realizes a backpack bag in which the auxiliary shoulder straps of the first aspect have been modified to be detachable. When the auxiliary shoulder straps are not needed, they can be removed.

[0023] The fourth aspect of the present invention is a backpack bag according to the first or third aspect, in which the auxiliary shoulder straps (5) are belt-shaped at the shoulders and have a narrower belt-like or linear shape below that.

[0024] With this configuration, the shoulder portions of the auxiliary shoulder straps are strip-shaped, which reduces the burden on the shoulders when carrying the bag. At the same time, the portion below the strip-shaped portion is narrower, strip-shaped or linear, so when the tip of the auxiliary shoulder strap is fastened to the front portion of one of the main shoulder straps on the shoulder, the portion where the auxiliary shoulder strap hangs down in a U-shape is narrow strip-shaped or linear, which improves the appearance.

[0025] A fifth aspect of the present invention is the backpack bag according to the fourth aspect, wherein the strap-like shoulder portions of the auxiliary shoulder straps (5) are set to a length that does not touch the ground when the bag body (1) is placed on the ground. With this configuration, the strap-like shoulder portion of the auxiliary shoulder strap touches the neck when the bag body is moved back and forth, which satisfies the user's tendency to dislike that part touching the ground. [Effects of the Invention]

[0026] As described above, according to the present invention, a backpack bag can be realized that can be moved between the front and back of the body without having to be lowered onto the ground or floor, and that is easy to operate, practical, and looks good. [Brief explanation of the drawings]

[0027] [Figure 1] 1 is a perspective view illustrating the configuration of a backpack bag according to an embodiment of the present invention; [Figure 2] 2A to 2C are explanatory diagrams illustrating an example of how to use the backpack bag of FIG. 1. [Figure 3] FIG. 10 is a perspective view illustrating the configuration of a backpack bag according to another embodiment of the present invention. [Figure 4] FIG. 10 is a perspective view illustrating the configuration of a backpack bag according to yet another embodiment of the present invention. [Figure 5] FIG. 10 is a perspective view illustrating the configuration of a backpack bag according to yet another embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0028] FIG. 1 is a perspective view illustrating the configuration of a backpack bag according to one embodiment of the present invention. This backpack bag 101 has a bag body 1, a pair of left and right main shoulder straps 3 and 4, and an auxiliary shoulder strap 5. The bag body 1 contains an object to be contained (not shown). In the illustrated example, the top lid can be opened and closed freely with a zipper, but as is well known, the structure of the bag body 1 can take various forms.

[0029] The main shoulder straps 3, 4 are connected to the bag body 1 and allow the bag body 1 to be carried on the back by hanging them over the left and right shoulders. In the illustrated example, upper ends 31, 41 of the main shoulder straps 3, 4 are connected to the upper left and right ends of the back panel (rear body) 7 of the bag body 1, and lower ends 33, 43 are connected to both left and right ends of the lower part of the back panel 7. In the illustrated example, reinforcing members 35, 45 are provided on the bag body 1 to reinforce the connecting parts between the lower ends 33, 43 of the main shoulder straps 3, 4 and the bag body 1.

[0030] In the illustrated example, the shoulder portions of the main shoulder straps 3, 4 (the portions that correspond to the shoulders when the bag is carried on the user's back) are wide and belt-like from front to back. This reduces the burden on the shoulders when the bag body 1 is carried on the user's back. In the illustrated example, the portions of the main shoulder straps 3, 4 below the wide and belt-like portions are narrower and belt-like. Although not shown, the main shoulder straps 3, 4 may be provided with a length adjustment device, as is well known.

[0031] Auxiliary shoulder strap 5 has a base end 8 connected to the shoulder portion of main shoulder strap 3, and one of two detachable fasteners 9 (fastener 9A) connected to a tip 10. In the illustrated example, base end 8 is connected to the upper part of the shoulder portion of main shoulder strap 3. In the illustrated example, auxiliary shoulder strap 5 has a band-like shape at the shoulder, and the portion below that is linear and narrower than the band-like portion.

[0032] The other fastener 9 (fastener 9B) is connected to the front portion of the main shoulder strap 3 so as to be positioned in front of the shoulder. The other fastener 9 (fastener 9C) is connected to the main shoulder strap 4 via string 13 to a portion 11 of the bag body 1 that overlaps the connection between the lower end 43 of the main shoulder strap 4 and the bag body 1 so as to be positioned in the waist area near the main shoulder strap 4. The tip 10 of the auxiliary shoulder strap 5 can be held in place by fastening fastener 9A to fastener 9B, so as to be positioned in the waist area near the main shoulder strap 4.

[0033] When fastener 9A is attached to fastener 9C, auxiliary shoulder strap 5, together with the portion of main shoulder strap 3 near upper end 31, forms a shoulder strap for hanging a kesa. The length of auxiliary shoulder strap 5 is set to a length that forms a shoulder strap for hanging a kesa. A length adjustment device can also be provided on auxiliary shoulder strap 5. In that case, the length of auxiliary shoulder strap 5 can be adjusted to a length that forms a shoulder strap for hanging a kesa.

[0034] Figure 2 is an explanatory diagram illustrating an example of how to use backpack bag 101. When carrying bag body 1 behind the body, fasteners 9A connected to ends 10 of auxiliary shoulder straps 5 can be fastened to fasteners 9B to keep auxiliary shoulder straps 5 aligned with main shoulder straps 3 (Figure 2(a)). This prevents auxiliary shoulder straps 5 from appearing unnatural to onlookers and does not detract from the attractive appearance of backpack bag 101.

[0035] When moving the bag body 1 from the back to the front of the body, fastener 9A connected to the tip 10 of auxiliary shoulder strap 5 is removed from fastener 9B (FIG. 2(b)) and attached to fastener 9C (FIG. 2(c)). This allows the auxiliary shoulder strap 5 to be worn diagonally across the body, spanning from the shoulder near main shoulder strap 3 to the waist near main shoulder strap 4. Since the bag body 1 can then be carried by auxiliary shoulder strap 5, the main shoulder straps 3 and 4 can be removed from the shoulders while carrying the bag body 1, and the bag body 1 can be moved from the back to the front, and the main shoulder straps 3 and 4 can be placed over the opposite shoulder. In other words, the bag body 1 can be moved from the back to the front of the body without being lowered to the floor (FIGS. 2(d), (e), and (f)). By reversing the procedure, the bag body 1 can also be returned from the front to the back of the body without being lowered to the floor. These operations are simple and do not require any special effort.

[0036] As already mentioned, in the illustrated example, the auxiliary shoulder straps 5 have a strap-like shoulder portion. This reduces the burden on the shoulders when carrying the bag body 1. At the same time, the portion below the strap-like portion is narrower, so when the tip 10 of the auxiliary shoulder strap 5 is fastened to the front portion of the shoulder of the main shoulder strap 3, the portion where the auxiliary shoulder strap 5 hangs down in a U-shape is narrower and linear (FIG. 2(a)), which improves the appearance. The linear portion of the auxiliary shoulder strap 5 may also be a strap-like portion that is narrower than the strap-like shoulder portion.

[0037] Returning to Figure 1, the strap-like shoulder portions of auxiliary shoulder straps 5 are set to a length that will not touch the ground when bag body 1 is placed on the ground. This is in consideration of the user's dislike of the strap-like portions touching the ground when moving bag body 1 in front of or behind the body, as they come into contact with the neck.

[0038] Figure 3 is a perspective view illustrating the configuration of a backpack bag according to another embodiment of the present invention. This backpack bag 102 differs from backpack bag 101 (Figure 1) in the connection position of base ends 8 of auxiliary shoulder straps 5. Figure 3 illustrates two configurations in which base ends 8 are connected to a portion 15 that overlaps the connection between upper ends 31 of main shoulder straps 3 and bag body 1, and to a portion 17 of bag body 1 adjacent to the connection between upper ends 31 of main shoulder straps 3 and bag body 1. In these examples, auxiliary shoulder straps 5 can also serve as shoulder straps worn across the body of the bag.

[0039] FIG. 4 is a perspective view illustrating the configuration of a backpack bag according to yet another embodiment of the present invention. This backpack bag 103 differs from backpack bags 101 and 102 in the location at which fastener 9C is connected to bag body 1. In the example of FIG. 4, fastener 9C is connected to the waist portion of main shoulder strap 4 via string 13 so as to be located at the waist near main shoulder strap 4. FIG. 4 also illustrates an embodiment in which fastener 9C is connected via string 13 (shown by a dotted line) to region 18 of bag body 1 adjacent to the connection between lower end 43 of main shoulder strap 4 and bag body 1 so as to be located at the waist near main shoulder strap 4. Fastener 9C may also be connected directly to bag body 1 or main shoulder strap 4 without using string 13.

[0040] Additionally, backpack bag 103 differs from backpack bags 101 and 102 in that fastener 9B is connected to main shoulder strap 3 (in the illustrated example, the front portion thereof) via string 19 so that fastener 9B is located at the front portion of main shoulder strap 3. In this way, fastener 9B does not have to be directly connected to main shoulder strap 3.

[0041] FIG. 5 is a perspective view illustrating the configuration of a backpack bag according to yet another embodiment of the present invention. This backpack bag 104 differs from backpack bags 101-103 in that auxiliary shoulder straps 5 are detachable. In the illustrated example, one of detachable fasteners 21 (fastener 21A) is connected via string 23 to a portion 15 that overlaps the connection between upper end 31 of main shoulder strap 3 and bag body 1. The other fastener 21 (fastener 21B) is connected to base end 8 of auxiliary shoulder strap 5. By releasing fastener 21, auxiliary shoulder strap 5 can be detached from the rest of backpack bag 104. In this way, auxiliary shoulder strap 5 can be removed when not needed.

[0042] (Other embodiments) (1) The upper ends 31, 41 of the main shoulder straps 3, 4 can be connected to a location other than the back panel 7 of the bag body 1, for example, to the side or top surface of the bag body 1. Accordingly, the base end 8 of the auxiliary shoulder strap 5 can be connected to the bag body 1 overlapping the upper end 31 of the main shoulder strap 3 or adjacent to the upper end 31. The same applies to the end of the string 23 that connects to the fastener 21A. (2) Similarly, the lower ends 33, 43 of the main shoulder straps 3, 4 can also be connected to a location other than the back panel 7 of the bag body 1, for example, to the side or bottom surface of the bag body 1. Accordingly, the end of the string 13 connected to the fastener 9C can also be connected to the bag body 1 overlapping the lower end 43 of the main shoulder strap 4 or adjacent to the lower end 43. (3) As fasteners 9 and 21, in addition to common types that use only mechanical fastening mechanisms such as "snap hooks," "D-rings," and side release buckles, it is also possible to use fasteners that also use magnetic force, such as a fastener known as "FIDLOCK." In the latter case, fastening and detachment are particularly easy and are suitable for the present invention. [Explanation of symbols]

[0043] 1 bag body, 3,4 pair of left and right main shoulder straps, 5 auxiliary shoulder strap, 7 back panel (rear body), 35,45 reinforcing member, 8 base end, 9,9A,9B,9C fastener, 10 tip, 11 part, 13 string body, 15 part, 17 part, 18 part, 19 string body, 21,21A,21B fastener, 23 string body, 31,41 upper end, 33,43 lower end, 101,102,103,104 backpack bag.

Claims

1. A bag body (1) for storing an object to be stored; a pair of left and right main shoulder straps (3, 4) connected to the bag body (1) and allowing the bag body (1) to be carried on the back by hanging it over the left and right shoulders; an auxiliary shoulder strap (5) having a base end (8) connected to a portion (15, 17) of the bag body (1) near the upper end (31) of one of the pair of main shoulder straps (3, 4) or to a shoulder portion of the one of the main shoulder straps (3), and one (9A) of detachable fasteners (9) connected to a tip end (10); a first other (9B) of the fasteners (9) connected to the one main shoulder strap (3) so as to be located at a front portion of the shoulder of the one main shoulder strap (3); a second other (9C) of the fastener (9) connected to a portion (11, 18) of the bag body (1) near a lower end (43) of the other main shoulder strap (4) of the pair of main shoulder straps (3, 4) or to a waist portion of the other main shoulder strap (4) so ​​as to be located in the waist portion near the other main shoulder strap (4), The auxiliary shoulder strap (5) forms a shoulder strap for hanging across the body when the one side (9A) of the fastener (9) is attached to the second other side (9C) of the fastener (9).

2. A bag body (1) for storing an object to be stored; a pair of left and right main shoulder straps (3, 4) connected to the bag body (1) and allowing the bag body (1) to be carried on the back by hanging it over the left and right shoulders; one (21A) of first fasteners (21) detachably connected to a portion (15, 17) of the bag body (1) near an upper end (31) of one of the pair of main shoulder straps (3, 4) or to the shoulder portion of the one of the main shoulder straps (3); and one (9A) of the second fasteners (9) connected to the one main shoulder strap (3) so as to be located at a front portion of the shoulder of the one main shoulder strap (3), and a first other (9B) of the second fasteners (9) detachable from the one (9A) of the second fasteners (9); the one (9A) of the second fasteners (9) and the detachable second other (9C) of the second fasteners (9) are connected to a portion (11, 18) of the bag body (1) near a lower end (43) of the other main shoulder strap (4) of the pair of main shoulder straps (3, 4) or to a waist portion of the other main shoulder strap (4) so ​​as to be located at a waist portion near the other main shoulder strap (4); The other end (21B) of the first fastener (21) of the auxiliary shoulder strap (5) is connected to the base end (8) and the one end (9A) of the second fastener (9) is connected to the tip end (10) of the auxiliary shoulder strap (5) of an appropriate length, and the other end (21B) of the first fastener (21) is attached to the one end (21A) of the first fastener (21) and the one end (9A) of the second fastener (9) is attached to the second other end (9C) of the second fastener (9), thereby forming a shoulder strap for hanging across the body.

3. A backpack as described in claim 2, further comprising the auxiliary shoulder straps (5).

4. 4. The backpack bag according to claim 1 or 3, wherein the auxiliary shoulder straps (5) have a strap-like shape at the shoulders and a narrower, strap-like or linear shape at the lower portions.

5. 5. The backpack bag according to claim 4, wherein the auxiliary shoulder straps (5) have a length such that the strap-like shoulder portions do not touch the ground when the bag body (1) is placed on the ground.

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