Elongate articulated bending section body for an insertion endoscope

Abstract

A method for moulding an elongate articulated bending section body (4) for a medical device including a number of segments (7) interconnected via a number of hinge members (8). The method includes the use of a mould having a first number of sub-cavities where each of the sub-cavities has at least one external fluid inlet through which a liquified plastic material is injected into the mould. The sub-cavities are so distributed that each sub-cavity is separated from another sub-cavity by an odd number of sub-cavities without an external fluid inlet.

Claims

1. A method for molding a bending section body for a medical device, the method comprising: injecting a liquified plastic material through fluid inlets of a mold to form segments and hinges of the bending section body, the hinges formed in passages of the mold, and the segments formed in sub-cavities of the mold, the segments being interconnected by the hinges, wherein the sub-cavities are positioned parallel to each other and along a length of the mold and comprise fluid-inlet sub-cavities and inlet-free sub-cavities, each of the fluid-inlet sub-cavities being separated from another of the fluid-inlet sub-cavities by one of the inlet-free sub-cavities, wherein said injecting comprises injecting the liquified plastic material into the fluid-inlet sub-cavities solely through the fluid inlets and into the inlet-free sub-cavities through the passages, wherein a longitudinal center plane traverses the sub-cavities, and wherein the fluid inlets are offset in alternating directions from the longitudinal center plane.

2. The method of claim 1, wherein the sub-cavities are symmetrical about the longitudinal center plane.

3. The method of claim 1, wherein the mold comprises at least two mold parts, the method further comprising separating the at least two mold parts to remove the bending section body in one piece.

4. The method of claim 3, wherein the at least two separable mold parts are separable along the longitudinal center plane.

5. The method of claim 1, wherein the passages interconnecting the sub-cavities are offset 90 degrees from any adjacent passages.

6. The method of claim 1, wherein the sub-cavities comprise a first set of the sub-cavities, a second set of the sub-cavities, and a transition sub-cavity positioned between the first set and the second set, the sub-cavities in the second set being different from the sub-cavities in the first set and being different from the transition sub-cavity.

7. The method of claim 6, wherein the transition sub-cavity is configured to impart peripheral passages onto the segment molded therein.

8. The method of claim 7, wherein the sub-cavities in the first set and in the second set are devoid of peripheral passages.

9. The method of claim 6, wherein the transition sub-cavity is configured to impart peripheral passages onto the segment molded therein, and wherein the transition sub-cavity is one of the inlet-free sub-cavities.

10. The method of claim 1, wherein said injecting comprises injecting the liquified plastic material into the fluid-inlet sub-cavities until the liquified plastic material flows out of the fluid-inlet sub-cavities through the passages and into the inlet-free sub-cavities, wherein the liquified plastic material flows from a pair of the fluid-inlet sub-cavities into one of the inlet-free sub-cavities positioned between the pair until the liquified plastic material flowing from the pair of the fluid-inlet sub-cavities fuses in a welding zone, and wherein the welding zone is spaced from the hinges connecting the pair of the fluid-inlet sub-cavities to the one of the inlet-free sub-cavities.

11. The method of claim 10, wherein the sub-cavities comprise a first set of the sub-cavities, a second set of the sub-cavities, and a transition sub-cavity positioned between the first set and the second set, the sub-cavities in the second set being different from the sub-cavities in the first set and being different from the transition sub-cavity.

12. The method of claim 11, wherein the transition sub-cavity is configured to impart peripheral passages onto the segment molded therein.

13. The method of claim 12, wherein the sub-cavities in the first set and in the second set are devoid of peripheral passages.

14. The method of claim 11, wherein the transition sub-cavity is configured to impart peripheral passages onto the segment molded therein, and wherein the transition sub-cavity is one of the inlet-free sub-cavities.

Description

BRIEF DESCRIPTION OF THE FIGURES

(1) The disclosure will now be made in greater detail based on non-limiting exemplary embodiments and the appended drawings, on which:

(2) FIG. 1 shows a medical system comprising a display unit and an endoscope with an elongate articulated bending section body according to the disclosure,

(3) FIG. 2 shows a first embodiment of an elongate articulated bending section body according to the disclosure,

(4) FIG. 3 shows a second embodiment of an elongate articulated bending section body according to the disclosure,

(5) FIG. 4 shows a third embodiment of an elongate articulated bending section body according to the disclosure, and

(6) FIG. 5 schematically shows a mould for manufacturing an elongate articulated bending section body according to the disclosure.

DETAILED DESCRIPTION

(7) Turning first to FIG. 1 an overall medical system is shown. The medical system comprises a medical device exemplified by an endoscope 1 and a display unit 100 to which the endoscope 1 is connected by means of cable or a wireless connection 101. At the distal end of the insertion endoscope 1 the insertion tube 2 is terminated in a bending section 3. The bending section 3 comprises an elongate articulated bending section body 4 shown in various embodiments in FIGS. 2 to 4, but not visible in FIG. 1 as it is covered by an external sheath.

(8) Various embodiments of the bending section body 4 are shown in FIGS. 2 to 4. The bending section bodies 4 are shown in their relaxed, as made, state, that is to say without any external forces acting on them, and reference in the following are made to them in that state. Throughout the drawings the same reference numerals are used for identical or corresponding features.

(9) In FIG. 2 the bending section body 4 comprises a proximal segment 5 adapted for connection to the insertion tube 2, a distal segment 6 adapted for accommodating optics, vision device, illumination and other electronics in a manner per se known and not illustrated. Between the proximal segment 5 and the distal segment 6 a number of intermediate segments 7 are arranged. In FIG. 2 there are fourteen intermediate segments, so that the entire row of segments totals sixteen but the number of intermediate segments 7 could both be higher or lower depending on the actual design and purpose of the medical device. Between the segments a number of integrally moulded hinge members 8 are arranged, such as in particular integrally moulded foil hinges. The hinge members 8 in the embodiment of FIG. 2 are all arranged in the same longitudinal centre plane S essentially defining a symmetry plane about which the elongate articulated bending section body 4 is symmetrical or largely symmetrical, at least as far as the external features are concerned. Internally, the elongate articulated bending section body may comprise apertures, such as passages 9 for electrical wiring, optical fibres or the like, passages 10 for a working or suction channels, and passages 11 for pull-wires effecting the articulation of the bending section. Some of these passages could deviate from the symmetry as this is not important for the present disclosure. As shown, every second segment comprises a mark 12 corresponding to an external fluid inlet 13 of the injection mould 14 in which the elongate articulated bending section body 4 has been moulded, cf. FIG. 5. Material corresponding to the external fluid inlets 13 as such has been broken away after manufacture. In FIG. 2 the mould comprises two halves separable in opposite directions from the symmetry plane S and with the external fluid inlets 13 in the symmetry plane S. In FIG. 5 one mould half 15 is shown, together with various retractable cores 16, 17, 18. When closed, the mould 14 thus comprises a number of sub-cavities, each corresponding to a segment of the resulting elongate articulated bending section 4, each sub-cavity being separated from its neighbor except for the passages adapted for forming the hinge members 8, which thus serve as internal fluid inlets for those sub-cavities. As mentioned, the mould 14 comprises a number of retractable and/or collapsible cores 16, 17, 18 for forming the internal passages 9, 10 11. As will be understood every second of the sub-cavities does not comprise an external fluid inlet and may be referred to as an inlet-free sub-cavity while the sub-cavities including external fluid inlets may be referred to as fluid-inlet sub-cavities. During injection of the liquified moulding material into the mould via suitably configured feed channels 19, the inlet-free sub-cavities sub-cavities will be filled only indirectly with moulding material, i.e. via the sub-cavities with the external fluid inlets 13 and through the passages adapted to form the hinge members 8. With identical or largely identical sub-cavities and due consideration of the deviations of the sub-cavities for the proximal end segment 5 and the distal end segment 6, an odd number of cavities, in casu one, between each sub-cavity with an external fluid inlet, the flows of liquified moulding material from two sub-cavities with an external fluid inlet 13 can be made to meet and fuse together in the middle of intermediate sub-cavity without an external fluid inlet 13. The welding zone thus occurs in the bulk of the material of the intermediate segment 7 as far away from the more critical hinge members 8 as possible.

(10) Thus, when the liquified moulding material, which is preferably a plastic material, has been allowed to set to form said elongate articulated bending section body 4, the elongate articulated bending section body 4 can safely be removed from the mould 14 without the risk of breaking at the hinge members 8 at this stage or later during use.

(11) Turning now to FIGS. 3 and 4, slightly more complex articulated bending section bodies 4, where hinge members 8 lie in two planes, are shown. Thus, bending sections 2 incorporating these may bend in four directions, i.e. up, down, left and right, whereas with the elongate articulated bending section body 4 of FIG. 2 bending is only possible in one plane e.g. up and down (or left and right depending on how you see it). As shown, the segments 7 are shaped differently than a transition segment 7 and the segments 7 on the opposite side of the transition segment 7. The transition segment 7 is one of the intermediate segments and comprises a plurality of passages along its periphery. External fluid inlets 13 supply material to the segments on both sides of the transition segment 7.

(12) As will be noted, the marks 12 corresponding to the external fluid inlets do not lie in the same symmetry plane, but rather are alternatingly arranged on either side of the symmetry plane S. This further improves the control over the location of the welding zones in the segments 5, 6, 7 moulded in sub-cavities not provided with an external fluid inlet. In particular it ensures that the welding zones are away from the hinge members 8 on either side of an intermediate segment 7 which are off-set with an angle of 90 degrees with respect to each other.

(13) Although the symmetry plane is not shown in FIG. 4 it will be evident that also in that embodiment the external fluid inlets of the sub-cavities corresponding to every second intermediate segment are of the mould and, hence, the resulting marks 12 are arranged on either side of such a symmetry plane.

(14) As will be understood, the mould (not shown) for the embodiments of the elongate articulated bending section body of FIGS. 3 and 4 will comprise four mould quarters, retractable in orthogonal directions to allow for the easy manufacture of the 90 degree off-set hinge members 8, as well as retractable and/or collapsible cores for the longitudinal passages.

(15) The skilled person will understand that numerous embodiments of the elongate articulated bending section body are possible, and that features described above in conjunction with one embodiment is freely interchangeable with the other disclosed embodiments, as well as incorporable in embodiments not shown. The skilled person will also understand that deviation from the preferred odd number of one sub-cavity between sub-cavities with an external fluid inlet such as three or five will be possible.