Flexible fastener

Abstract: A flexible fastener (F) comprises a pair of opposed fastener strips (1), (2) each including a base plate (1'), (2'); and a longitudinal marginal grip portion (5), (6) integrally formed along one longitudinal edge thereof. A pair of opposed female and male coupling portion (3), (4) are mounted on the inner sides (1a), (2a) on the base plates (1'), (2') so as to project toward each other for coming into coupling engagement with each other, thereby releasably join the opposed fastener strips (1), (2). Two pairs of elongated ridges (8, 10; 9, 11) are provided on the inner sides (1a, 2a) of the fastener strips (1), (2), and a pair of elongated ridge (12), (13) are provided on the outer sides (1b), (2b) of fastener strips (1), (2) so as to provide increased friction between fingers and the fastener strips (1), (2).

Description: The present invention relates generally to a flexible fastener attached to a mouth edge of a bag, a pouch and so one, to open and close the mouth edge. A typical flexible fastener of the type described is disclosed in Japanese Utility Model Laid-open Publication No. 3-19313. The disclosed flexible fastener comprises a pair of opposed fastener strips having on their respective inner sides a male and a female locking portion for coupling engagement with each other and having respective opposed marginal grip portions diverged outward to facilitate grip and manipulation. In order to further facilitate grip the opposed marginal grip portions are provided at their edges with bulges. For opening the flexible fastener the opposed marginal grips are gripped and spread apart. However, the above-mentioned conventional flexible fastener suffers from drawbacks. In the conventional flexible fastener, the bulges are located at the very extremities of the grip portions. On the other hand, parts to be gripped by fingers for opening the fastener are far inner parts of the trip portions which are flat and have less friction. Since it is made of synthetic resinous film, the flexible fastener is very slippery. This requires a tight and forcible grip of the grip portions for opening the fastener. There is no problem where the fastener is opened only a few times. However, there are some circumstances which require one person to open thousands of flexible fasteners repeatedly like a worker in a grain factory. The worker is likely to suffer painful or paralysed fingers. A similar fastener is disclosed in document US-A-4 363 345. With the foregoing difficulties in view, it is therefore an object of the present invention to provide a flexible fastener wherein, for opening the fastener, the inner surface of fingers can touch the grip portion of the flexible fastener over a wider area, to thus provide increased friction. According to the present invention, there is provided a flexible fastener comprising a pair of opposed fastener strips each including a base plate; a longitudinal marginal grip portion integrally formed along one longitudinal edge thereof; a pair of opposed female and male coupling portions mounted on the inner sides of the base plates so as to project toward each other for coming into coupling, engagement with each other, thereby releasably joining the opposed fastener strips; a pair of opposed distal inner ridges provided longitudinally on the inner sides of the opposed fastener strips along the edges of the marginal grip portions, respectively; a pair of proximal inner ridges provided longitudinally along the inner sides of the fastener strips and disposed closer to the female and male coupling portions. respectively; and a pair of opposed outer ridges provided on the outer sides of the marginal grip portions and each disposed between the distal inner ridges and the proximal inner ridges, respectively. Many other advantages and features of the present invention will become manifest to those versed in the art upon making reference to the detailed description and the accompanying sheets of drawings in which preferred structural embodiments incorporating the principles of the present invention are shown by way of illustrative example. FIG. 1 is a side view of a flexible fastener according to the present invention. FIG. 2 is a view similar to FIG. 1 but showing another embodiment of the present invention. FIG. 3 is a prospective view showing the flexible fastener of FIG. 1 in use. FIG. 1 shows a flexible fastener F according to the present invention. The flexible fastener F is made of synthetic resin and broadly comprises a pair of elongated fastener strips 1, 2 opposed in surface-to-surface relation to each other. Each of the fastener strips 1, 2 generally comprises a base plate 1', 2' and a longitudinal marginal grip portion 5, 6 integrally formed therewith and joined along a curved or bent portion 20, 21. A pair of opposed elongated female and male coupling portion 3, 4 are integrally mounted longitudinally on the respective inner sides 1a, 2a of the base plates 1, 2' so as to project toward each other. The female coupling portion 3 is of C-shaped cross-section while the male coupling portion 4 is of arrow-shaped cross-section and is adapted for snap engagement with the C-shaped female coupling portion 3. The opposed fastener strips 1, 2 are releasably joined together by resiliently coupling the female and male coupling portions 3, 4, respectively. As shown in FIG. 1, the grip portions 5, 6 of the opposed fastener strips 1, 2 are diverged away from each other in the directions of their respective edges, thereby providing an ample space 7 for letting thumbs in between the opposed marginal grip portions 5, 6. A pair of opposed elongated distal inner ridges 8, 10 are provided along the edges of the inner sides 1a, 2a of the marginal grip portions 5, 6, respectively. Likewise, a pair of elongated proximal inner ridges 9, 11 are provided longitudinally on the inner sides 1a, 2a of the fastener strips 1, 2 and disposed along the curved or bent portions 20, 21, respectively. Furthermore, a pair of opposed elongated outer ridges 12, 13 are provided on the outer sides 1b, 2b of the marginal grip portions 5, 6 and each disposed between the distal inner ridges 8, 10 and the proximal inner ridges 9, 11, respectively. In this embodiment, one marginal grip portion 5 is formed shorter than the other grip portion 6. And, the proximal inner ridges 9, 11 are out of registry with each other. The flexible fastener F of the construction set forth hereinabove is attached to a mouth edge 15 of a pouch 14 or the like by adhering or otherwise fastening the opposed fastener strips 1, 2 along their respective inner edges to the mouth edge 15 of the pouch 14, as better shown in FIG. 3. For closing the flexible fastener F, the opposed fastener strips 1, 21 are compressed until the female and male members 3, 4 on the inner sides 1a, 2a of the fastener strips 1, 2, respectively come into coupling engagement with each other, so that the fastener F and hence the pouch 14 is closed. For opening the flexible fastener F, as better shown in FIG. 3, both thumbs are wedged into the space 7 between the opposed marginal grip portions 5, 6. Then, the marginal grip portions 5, 6 are gripped by the thumbs and the forefingers and spread apart until the female and male coupling portions 3, 4 come out of coupling engagement with each other, so that the fastener F and hence the pouch 14 are opened. In this event, the thumbs press against the marginal grip portions 5, 6; to be specific, they touch both distal and proximal ridges 8, 10; 9, 11 and the inner sides 1a, 2a of the marginal grip portions 5, 6 interposed between the ridges 8, 10; 9, 11. Further, the forefingers engage the outer ridges 12, 13. This provides increased frictional resistance between the fingers and fastener strips 1, 2 and thus ensures that fingers can make a very firm grip on the fastener strips 1, 2, even if less force is applied thereto. Consequently, even repeated opening and closing operation of the fastener F would never cause pain or paralysis of the fingers. FIG. 2 shows a flexible fastener F' according to another embodiment of the present invention. The flexible fastener F' is substantially identical with the flexible fastener F according to the preceding embodiment except that the opposed longitudinal marginal grip portions 5', 6' are the same in length and that the proximal inner ridges 8, 9 are properly in registry with each other. With the construction set forth hereinabove, fingers can make a very firm grip on the fastener strips 1, 2, when opening the fastener; nevertheless, even repeated opening and closing operation of the fastener will never cause pain or paralysis of the fingers.

Claims: A flexible fastener (F) comprising a pair of opposed fastener strips (1), (2) each including a base plate (1'), (2'); a longitudinal marginal grip portion (5), (6) integrally formed along one longitudinal edge thereof; a pair of opposed female and male coupling portion (3), (4) mounted on the inner sides (1a), (2a) of the base plates (1'), (2') so as to project toward each other for coming into coupling engagement with each other, thereby releasably joining the opposed fastener strips (1), (2); and a pair of opposed distal inner ridges (8), (10) provided longitudinally on the inner sides (1a), (2a) of the opposed fastener strips (1), (2) along the edges of the marginal grip portions (5), (6), respectively; characterized in that the flexible fastener (F) further includes a pair of proximal inner ridges (9), (11) provided longitudinally along the inner sides (1a), (2a) of the fastener strips (1), (2) and disposed closer to the female and male coupling portions (3), (4), respectively; and a pair of opposed outer ridges (12, 13) provided on the outer sides (1b), (2b) of the marginal grip portions (5), (6) and each disposed between the distal inner ridges (8), (10) and the proximal inner ridges (9), (11), respectively. A flexible fastener (F) according to claim 1, the longitudinal marginal grip portions (5), (6) of the opposed fastener strips (1), (2) being diverged away from each other in the direction of their respective edges. A flexible fastener (F) according to claim 1, the proximal inner ridges (9), (11) running along curved or bent portions (20), (21) defined between the base plates (1'), (2') and the longitudinal marginal grip portions (5), (6), respectively. A flexible fastener (F) according to claim 1, the proximal inner ridges (9), (11) of the opposed fastener strips (1) (2) being out of registry with each other.

Inventors: MASAHIRO NAYA, TSUTOMU HAMATANI, MASAHIRO, NAYA, TSUTOMU, HAMATANI
Applicants: YKK CORP, YKK CORPORATION
Application year: 1993
Main classification: B65D33
IPC codes: A44B19, B65D33