Articulated, four-way bendable tube structure

• US 4,108,211 A
• Filed: 04/21/1976
• Issued: 08/22/1978
• Est. Priority Date: 04/28/1975
• Status: Expired due to Term

• Current Assignee: Fuji Photo Optical Co. Ltd (Fujifilm Holdings Corporation)
• Original Assignee: Fuji Photo Optical Co. Ltd (Fujifilm Holdings Corporation)
• Inventors: Tanaka, Hitoshi
• Primary Examiner(s): Bell, Jr., Houston S.
• Assistant Examiner(s): Footland, L.
• Application Number:
  US05/678,736
• Time in Patent Office: 853 Days
• Field of Search: 138/120, 138/118, 138/118.1, 128/4, 128/6, 128/7, 128/8
• US Class Current: 138/120
• CPC Class Codes: A61B 1/0055 Constructional details of insertion parts, e.g. vertebral elements

Abstract

An articulated tube structure to be arranged next to the head of a fiberoptic endoscope to permit same to be tilted in either of four different directions by manipulation of pull wires. The tube structure comprises a series of relatively short elementary tubes each having two pairs of lugs on its opposite ends which are angularly displaced 90° from each other. These elementary tubes are jointed in spaced end-to-end relationship by wire support members passing through their overlapped lugs. The wire support members have holes in their ends located inside the tube structure, and the pull wires extend through the holes with clearance. A recessed inner tube can be nested in each elementary tube to eliminate unevenness of the internal surfaces of the tube structure.

Claims

1. An articulated tube structure which can be bent selectively in four different directions by means of pull members extending therethrough, comprising in combination, a plurality of relatively short elementary tubes arranged end-to-end with uniform spacings therebetween and having a common axis when in alignment, a pair of lugs formed in diametrically opposite positions on one end of each of said elementary tubes, said pair of lugs being depressed radially inwardly of each said elementary tube so as to underlie the adjacent elementary tube, there being a first pair of pivot holes formed respectively in each of said pair of lugs on each of said elementary tubes, there being a second pair of pivot holes formed in diametrically opposite positions in the other end of each of said elementary tubes, said second pair of pivot holes in each of said elementary tubes being angularly spaced around said axis 90°

from said first pair of pivot holes and being aligned respectively with said first pair of pivot holes in the next adjacent pair of lugs lying thereunder and thereby forming two pairs of aligned pivot holes for each of said tubes with one of said pairs being at each end of the tube and with said pairs being angularly spaced 90°

around said axis with respect to each other, a plurality of pivot members corresponding in number with said aligned pivot holes and associated respectively therewith, each of said pivot members having a shank portion which is snugly received in its aligned holes to provide a pivotal connection therebetween and also having a bracket portion positioned toward said axis and having a bore therethrough which is parallel to said axis, whereby there are four of said bores upon said pivot members of each of said tubes which are angularly spaced 90°

from each other with respect to said axis, and four pull members extending the length of said tube structure in parallel relationship when said tubes are in axial alignment and extending through the respective bores with each pull member extending through a bore of a pivot member for each of said tubes.

2. The articulated tube structure as recited in claim 1, wherein each said wire support member is made of malleable material and has said one end thereof enlarged so as to be incapable of passing through said first and second holes, each said wire support member having another end which is clinched on the outside of the tube structure to make the wire support member irremovable.

3. The articulated tube structure as recited in claim 1, further comprising a plurality of inner tubes each adapted to fit snugly in one of said elementary tubes for eliminating the unevenness of the internal surfaces of the tube structure due to the presence of said pairs of lugs.

4. The articulated tube structure as recited in claim 3, wherein said pair of lugs are depressed together with neighboring regions of each said elementary tube, and wherein each said inner tube has a pair of recesses formed in diametrically opposite positions at one end thereof for receiving said depressed regions of one of said elementary tubes in which the inner tube is fitted.

5. The articulated tube structure as recited in claim 4, wherein each said inner tube has a second pair of recesses formed in diametrically opposite positions at another end thereof for receiving with clearance said pair of lugs on the elementary tube next to the one in which the inner tube is fitted, said second pair of recesses in each said inner tube being angularly displaced 90°

from the first recited pair of recesses therein.

6. An articulated tube structure comprising, the combination of, a plurality of tube elements each of which comprises an annular portion with its axis forming a portion of the axis of the tube structure, said tube elements being equally spaced in alignment to provide a continuous array thereof, each of said tube elements having two pairs of lugs integral with said annular portion with said pairs extending parallel to said axis and in opposite directions from said annular portion, the lugs of each of said pairs being diametrically opposite from each other and said pairs being offset 90°

from each other relative to said axis, the lugs of one of said pairs being in substantial longitudinal alignment with said annular portion and the lugs of the other of said pairs being offset radially inwardly with respect to said annular portion substantially the thickness of the lugs of said first pair, each of said tube elements being positioned with its said first pair of lugs in mating relationship with said second pair of lugs of the next adjacent tube element, each of said lugs having a pivot hole extending radially with respect to said axis and in alignment with the hole in its mating lug, a plurality of pivotal connectors corresponding in number to the number of said mating lugs and associated respectively therewith, each of said pivotal connectors extending through said holes in its pair of lugs and providing a pivotal relationship therebetween about a pivot axis which intersects the axis of that tube element, each of said pivotal connectors having a hole which is parallel to said axis of its tube element whereby said pivotal connectors provide four sets of holes each of which has its axis in substantial alignment with said axis of the articulated tube, and four elongated members which extend respectively through said four sets of holes of each tube element, each of said elongated members being attached at one end of said articulated tube structure whereby it may be pulled at the opposite end to bend said tube structure.

7. The construction as described in claim 6 which includes a plurality of sleeve elements each of which is annular and is snugly received within one of said tube elements between two adjacent pairs of said pivotal connectors and having four notches in which the respective pivotal connectors are positioned.

8. The construction as described in claim 6 wherein said holes in the lugs of said first pairs are smaller than the holes in the lugs of said second pairs, and wherein each of said pivotal connectors presents two shoulders which clamp its hole of said first pair, and a third shoulder which clamps its lug of said second pair against its lug of said first pair.