Tightening string for an endoscope, outer cover securing method, flexible tube for an endoscope, and an endoscope

摘要

A tightening string is used in an endoscope for firmly securing an outer cover of a flexible tube of the endoscope onto an internal member disposed inside the outer cover. The tightening string is comprised of a filament assembly formed by bundling a plurality of filaments made of a synthetic resin. The invention also provides an outer cover securing method, a flexible tube for an endoscope, and an endoscope equipped with the flexible tube. An outer cover securing method using the tightening string, a flexible tube for an endoscope equipped with the thus secured outer cover, and an endoscope equipped with the flexible tube are also provided.

主权项

1. A flexible tube for an endoscope, the flexible tube configured to be inserted into a body cavity of a patient, comprising:
a flexible tubular portion including a core member and an outer cover which covers an outer periphery of the core member, the flexible tubular portion having a tip end and a base end; a bendable portion provided at the tip end of the flexible tubular portion and including a core member and an outer cover which covers an outer periphery of the core member, the bendable portion having a tip end and a base end; and a tightening string for securing an end portion of the outer cover of the bendable portion at a side of the base end and an end portion of the outer cover of the flexible tubular portion at a side of the tip end, onto the core member of the bendable portion or the core member of the flexible tubular portion, the tightening string comprising a first filament bundle comprising a plurality of filaments twisted together and a second filament bundle comprising a plurality of filaments twisted together, wherein the first and second filament bundles are twisted together to provide the tightening string, and wherein a number of twistings of the filaments in each of the first filament bundle and the second filament bundle is in a range of 1000 to 5000 T/m, a number of twistings of the first filament bundle and the second filament bundle is in a range of 1200 to 3000 T/m, and the number of twistings of the filaments in each of the first filament bundle and the second filament bundle is greater than the number of twistings of the first filament bundle and the second filament bundle.