Abstract The attachment point disclosed herein is adapted for applying a substantial load to a fabric sheet. A particularly fitting example of an application for such an attachment point is at the clew of a sail such as a Genoa jib where, in a large sailboat, the jib sheet (a rope) may be holding the sail in position under a load of several hundreds to several thousands of pounds. The attachment point employs a pair of complementary ring members, each having a multiplicity of needle-like teeth. These ring members are clamped on opposite sides of a plurality of cloth layers by means of a metallic inner liner which is rimmed down over the ring members so as to apply a clamping force sufficient to prevent combing of the teeth through the cloth layers under a lateral pressure in the same order of magnitude as the strength of the cloth layers themselves.
In a sail, an attachment point for applying and distributing a substantial local load to the sail, said attachment point comprising: a plurality of cloth layers sewn to the sail for distributing said load, said layers being apertured at the desired point of attachment; a pair of complementary ring members investment cast of stainless steel, each of which has on one side a substantially flat face and on the other side a substantially toroidally rounded surface, each ring member including also a multiplicity of integral needle-like teeth of round cross section upstanding from the respective flat face, said teeth being adapted to pierce the weave of said cloth layers without substantial disruption thereof; a stainless steel, generally tubular liner extending through one of said ring members, the aperture in said cloth layers and the other of said ring members, said liner being rimmed substantially symmetrically over the rounded surfaces of both of said ring members thereby to clamp said multiple cloth layers between said rings under sufficient force to substantially prevent combing of said teeth through the cloth under a lateral pressure in the same order of magnitude as the strength of said cloth layers.
Claim 2
Dependent Claim
195 words
In a sail, an attachment point for applying and distributing a substantial local load to the sail, said attachment point comprising: a plurality of cloth layers sewn to the sail for distributing said load, said layers being apertured at the desired point of attachment; a pair of complementary ring members investment cast of stainless steel, each of which has on one side a substantially flat face and on the other side a substantially toroidally rounded surface, each ring member including also a multiplicity of integral needle-like teeth of round cross section upstanding from the respective flat face, said teeth being adapted to pierce the weave of said cloth layers without substantial disruption thereof; a stainless steel, generally tubular liner extending through one of said ring members, the aperture in said cloth layers and the other of said ring members, said liner being rimmed substantially symmetrically over the rounded surfaces of both of said ring members thereby to clamp said multiple cloth layers between said rings under sufficient force to substantially prevent combing of said teeth through the cloth under a lateral pressure in the same order of magnitude as the strength of said cloth layers.
Claim 3
Dependent Claim
24 words
An attachment point as set forth in claim 1 wherein said liner is rimmed over under a force in the order of 30 tons.