Hook structure for molded surface fastener

摘要

In a hook structure for a molded surface fastener, in an arbitrary cross section of each of a stem (11) and a hook-shape engaging portion (12) of a hook (10), the cross-sectional area is divided into front and rear side cross-sectional areas (S1), (S2) with respect to the center line of the hook (10), and the front side cross-sectional area (S1) is defined to be larger than the rear side cross-sectional area (S2). Therefore, the neutral plane of the hook (10) is shifted toward the front side of the stem (11) and the inner side of the hook-shape engaging portion (12) to a further extent than conventional to reduce possible tensile stresses in the front part of the stem (11) and the inner part of the hook-shape engaging portion (12) so that, as compared to the conventional hook made of the same resin quantity and having a substantially similar shape, the strength of the hook is increased sharply and, necessarily, both the front part of the stem and the inner part of the hook-shape engaging portion is increased in rigidity as compared to the other part and hence is difficult to deform, thus causing an increased strength as well as an increased force of engagement with a loop of a companion surface fastener.