Flexible sheathing tube construction

• US 5,746,696 A
• Filed: 04/24/1996
• Issued: 05/05/1998
• Est. Priority Date: 05/16/1995
• Status: Expired due to Fees

• Current Assignee: Fujinon Corporation (Fujifilm Holdings Corporation)
• Original Assignee: Fuji Photo Optical Co. Ltd (Fujifilm Holdings Corporation)
• Inventors: Kondo, Mituo
• Primary Examiner(s): FLANAGAN, BEVERLY MEINDL
• Application Number:
  US08/636,265
• Time in Patent Office: 741 Days
• Field of Search: 600/139, 600/140, 600/141, 600/143, 600/144, 138/120, 138/141, 138/142, 138/177, 604/280, 604/282, 604/264
• US Class Current: 600/139
• CPC Class Codes: A61B 1/00078 with stiffening means
• CPC Class Codes: A61B 1/0011 Manufacturing of endoscope parts
• CPC Class Codes: A61B 1/0055 Constructional details of insertion parts, e.g. vertebral elements
• CPC Class Codes: A61M 25/0009 Making of catheters or other medical or surgical tubes
• CPC Class Codes: A61M 25/005 with embedded materials for reinforcement, e.g. wires, coils, braids

Abstract

A flexible sheathing tube particularly suitable for use on an endoscopic insertion rod or flexible light guide cable, the sheathing tube having a laminated wall basically including a helical coil as a flexible base structure and a tubular metal wire netting placed around the helical coil member. The helical coil member has a certain number of helices thereof tightly closed and fixed to each other into the form of a rigid ring at least at one end of the sheathing tube to be trimmed in a subsequent stage. The end ring provides a rigid support uniformly on and around the inner periphery of the tubular netting, permitting a cutter blade to cut the end of the sheathing tube to a predetermined length by a straight clear cut through the laminated wall and the backing end ring. Accordingly, flexible component parts which are received in the sheathing tube are free from damages as caused by metal wires of the tubular netting which would otherwise be unraveled and deformed to protrude inward of the sheathing tube at the time of an end trimming operation.

Claims

1. A flexible sheathing tube for use on an endoscope, said sheathing tube having a laminated wall including, from the inner side thereof, a flexible helical coil structure formed by helically winding a metal strip in a predetermined open pitch, a tubular metal wire netting fitted on said helical coil structure, and an outer skin layer laminated on said tubular netting, characterized in that:

said helical coil structure is constituted by at least one helical coil member having a number of helices thereof tightly closed and fixed to each other into the form of a rigid ring at least at one end of said sheathing tube to be trimmed in a subsequent stage, said rigid ring providing a solid backing support uniformly on and around the inner periphery of said tubular metal wire netting in such a way as to permit a cutter blade to trim said sheathing tube to a predetermined length by a straight clear cut through said tubular metal wire netting and helical coil member of said laminated wall.

2. A flexible sheathing tube as defined in claim 1, wherein said helical coil structure is constituted by a couple of superposed helical coil members of opposite winding directions, at least one of said helical coil members having a number of helices tightly closed and fixed to each other into the form of a rigid ring at one end of said sheathing tube to be trimmed in a subsequent stage, closed helices of said one helical coil member being securely fixed to helices of the other helical coil member.

3. A flexible sheathing tube as defined in claim 1, wherein said flexible coil structure comprises a single helical coil member having a plurality of helices thereof tightly closed and fixed to each other into the form of a rigid ring at one end of said sheathing tube to be trimmed in a subsequent stage, closed helices of said helical coil member being securely fixed to each other along a helical seam line between closed helices.

4. A flexible sheathing tube according to any one of claims 1 to 3, wherein closed helices of said coil member are set in a ring-like form by means of laser spot welding.

5. A flexible sheathing tube according to any one of claims 1 to 3, wherein said tubular wire metal netting is set with solder in areas overlying said closed helices of said coil member.