GB2610647A

GB2610647A - Endoscopy system & elements thereof

Info

Publication number: GB2610647A
Application number: GB2113116.4A
Authority: GB
Inventors: Miller Andrew; Ward-Booth Patrick; Earl Nick
Original assignee: I Q Endoscopes Ltd
Current assignee: I Q Endoscopes Ltd
Priority date: 2021-09-14
Filing date: 2021-09-14
Publication date: 2023-03-15
Anticipated expiration: 2041-09-14
Also published as: GB202113116D0; WO2023041377A1; GB2610647B

Abstract

An articulated member, forming a vertebral structure for the steering section of a flexible endoscope, comprises a plurality of annular vertebral elements 34 defining a central aperture. Each ring link 34 comprises a pair of forwardly extending tabs 36a-b comprising opposing jaws, and a pair of rearwardly extending tabs 38a-b comprising respective pins or posts. The opposing jaws of each forwardly extending tab define a slot therebetween for receiving a pin of the adjacent ring element, each slot having a tapered opening (46, Fig. 6) narrowing to less than the diameter of the pins of the rearwardly extending tabs, such that the forwardly and rearwardly extending parts of adjacent ring elements achieve a snap-fit connection and form the respective hinge articulation. Each ring link further comprises a pair of integral steering wire guide conduits with flared or chamfered openings (50a-b, Fig. 5).

Description

ENDOSCOPY SYSTEM & ELEMENTS THEREOF Field of the Invention The present invention relates to imaging endoscope systems, elements thereof and particularly to an articulated member for use in an imaging endoscope systems.

Background

It is known that early detection of disease may be assisted by endoscopic examination of internal structures such as the alimentary canals and airways, e. g., the oesophagus, lungs, colon, uterus, and other organ systems. Endoscopic examination may be carried out using an imaging endoscope. Typically, an imaging endoscope has a flexible tube providing a light guide that guides illumination light from an external light source located proximally of the flexible tube to a distal tip of the flexible tube. The illumination light thereby illuminates the tissue to be examined. The distal tip typically also includes an objective lens to gather light from the tissue being examined. The flexible tube provides an imaging light guide to carry the light away from the distal tip and to a camera at the proximal end of the flexible tube. It is also known for the imaging light guide to be dispensed with and replaced with an imaging camera chip at the distal tip. In this case, the signal from the imaging camera chip is conducted along electrical wires in the flexible tube. Based on either approach, an image is produced for display to the imaging endoscope operator.

It is also known, in addition to the imaging function described above, for imaging endoscopes to provide further functionality. For example, it is known for the distal tip to be equipped with a port for dispensing air (or more generally, insufflation gas) to inflate the internal structure being examined, a port for dispensing irrigation liquid such as water or saline, and a port for a medical tool such as biopsy forceps. To allow such services to be provided, the flexible tube typically provides suitable lumens dedicated to the provision of these services.

Although some endoscopic procedures can be carried out with a rigid insertion tube, for many procedures it is preferred that the insertion tube is flexible. This allows the insertion tube to be located along tortuous and often complex paths within the body. To allow adequate steering of the flexible tube within the body, it is known to provide the distal tip of the insertion tube with means for deflecting the distal tip, and therefore with means to steer the distal tip. A typical approach to this is to provide control wires, extending along the flexible tube from a control handle at a proximal end of the flexible tube and anchored to the distal tip. The control handle has control knobs to allow movement of the control wires and consequently steering of the distal tip.

Various arrangements to allow flexibility of the insertion section, and in particular the distal tip of the insertion section (sometimes referred to as a 'steering section') are known.

For example, GB 2569013 discloses an imaging endoscope having an articulated steering section. The steering section comprises a series of links formed by stamping and bending of sheet metal, the links being pivotably connected to each other. The links are connected by hinges permitting only limited pivoting between adjacent links.

EP2617350 B1 describes multiple different possible configurations of a bendable insertion section and steering section of an imaging endoscopy system.

However, many existing articulating members for endoscopy systems are complex to manufacture or assemble, or relatively high cost to produce, thereby making them unsuitable or undesirable for use in low cost endoscopy systems, such as single use endoscopy systems.

The present invention has been devised in light of the above considerations.

Summary of the Invention

Accordingly, in a first aspect, the present invention provides an imaging endoscope comprising: a hand controller; an insertion section having a proximal end connected to the hand controller and a distal end for insertion into a subject, wherein a distal tip assembly is located at the distal end of the insertion section and a steering section is located adjacent and proximal to the distal tip; wherein: the steering section is bendable for steering by operation of the hand controller, the steering section comprising: a plurality of ring links having a body and a central aperture, each ring link comprising a pair of forwardly-extending tabs comprising opposing jaw parts, and a pair of rearwardly extending tabs comprising respective post portions, wherein the opposing jaw parts of each forwardly-extending tabs have a post-receiving slot formed therebetween, the post receiving slot having a tapered lead-in portion with a width narrower than a diameter of the post portions of the rearwardly extending tabs at at least one point, such that the forwardly and rearwardly extending tabs are configured for snap-fit connection with respective forwardly and rearwardly extending tabs of an adjacent ring link; and wherein each ring link further comprises a pair of integral wire guide conduits, each integral wire guide conduit having a chamfered lead-in portion.

In a second aspect, the present invention provides an articulated member for a steering section of an endoscope, the articulated member comprising: a plurality of ring links having a body and a central aperture, each ring link comprising a pair of forwardly-extending tabs comprising opposing jaw parts, and a pair of rearwardly extending tabs comprising respective post portions, wherein the opposing jaw parts of each forwardly-extending tab have a post-receiving slot formed therebetween, the post receiving slot having a tapered lead-in portion with a width narrower than a diameter of the post portions of the rearwardly extending tabs at at least one point, such that the forwardly and rearwardly extending tabs are configured for snap-fit connection with respective forwardly and rearwardly extending tabs of an adjacent ring link; and wherein each ring link further comprises a pair of integral wire guide conduits, each integral wire guide conduit having a chamfered lead-in portion.

The present inventors have found that providing an articulated member for a steering section of an endoscope as set out above may offer a number of advantages as compared with other known articulated members for use in the steering section of an endoscope. In particular, the provision of a pair of forwardly-extending tabs comprising opposing jaw parts, and a pair of rearwardly extending tabs comprising respective post portions on each ring link, said tabs being configured for snap-fit connection, can significantly improve the speed of manufacture of an endoscope incorporating the articulated member as a component of the steering section of the endoscope. Furthermore, as this snap-fit connection is provided by an arrangement in which the opposing jaw parts of each forwardly-extending tabs have a post-receiving slot formed therebetween, the post receiving slot having a tapered lead-in portion with a width narrower than a diameter of the post portions of the rearwardly extending tabs at at least one point, the snap-fit connection may be both quick to assemble (the tapered lead-in portions acting to guide the post portions into the post-receiving slot during assembly), whilst also providing relatively secure attachment of adjacent ring links (as the portion of the post-receiving slot having a width narrower than a diameter of the post portions of the rearwardly extending tabs may act as a limit stop to prevent relative longitudinal movement of adjacent ring links after connection).

Furthermore, provision of a pair of integral wire guide conduits, each integral wire guide conduit having a chamfered lead-in portion offers additional potential for improvement in the speed of manufacture of an endoscope incorporating the articulated member as a component of the steering section of the endoscope: chamfered lead-in portions can act as a guide during threading of the steering wires, meaning that less accurate alignment of the steering wires with the wire guide conduit is necessary during assembly of the device.

Accordingly, the specific features of the ring links of the articulated member synergistically act together to improve speed of manufacture of an endoscope incorporating the articulated member as a component of the steering section of the endoscope.

Further optional features of the articulated member will now be discussed.

The forwardly-extending tabs of each ring link may be oppositely disposed about a circumferential edge of the respective ring link body. In other words, the forwardly-extending tabs may be located at 1800 relative to one another about the ring link body. In some arrangements, a radially outer surface of the forwardly-extending tabs may be contiguous with a radially outer surface of the ring link body.

The forwardly-extending tabs may be generally arcuate in shape, with each of the opposing jaw parts having an arcuate form. The opposing jaw parts may be tapered along their length. For example, they may be tapered in a rearwardly extending direction to allow flexibility of the opposing jaw parts in a radial direction with respect to the body of each ring link during snap-fit connection of adjacent ring-links. This can allow for adjacent ring links to be joined by snap fit connection even if they are slightly misaligned at the time of connection.

The forwardly-extending tabs may comprise a tab reinforcement portion. In preferred arrangements, the tab reinforcement portion comprises an integral, locally-thickened portion of the forwardly-extending tabs. The term locally-thickened' is used herein to define that the tab reinforcement portion is thickened relative to (i.e. thicker than) another part of the forwardly-extending tabs. Preferably, the tab reinforcement portion is thicker than the opposing jaw parts of the forwardly-extending tabs. In some arrangements, the tab reinforcement portion has a thickness that is at least the same thickness again as the thickness of the opposing jaw parts at the point that they connect to the tab reinforcement portion. The thickness of the tab reinforcement portion may vary in a circumferential direction about the ring link body. For example, the thickness of the tab reinforcement portion at a circumferentially outer point of the tab may be at least 1.1 times the thickness of the locally-thickened portion at a circumferentially inner point of the tab.

Provision of a tab reinforcement portion as described above can strengthen the tabs and reduce the risk of accidental damage to the tabs during snap-fit connection of the ring link to an adjacent ring link, or during bending of the articulated member, by providing increased durability of the tabs. Where a tab reinforcement portion is provided, this may comprise a post receiving surface situated distal from a point of connection between each forwardly-extending tab portion and the ring link body. This post receiving surface may be configured to receive a post portion of a rearwardly-extending tab portion of an adjacent ring link on snap fit connection of said links.

The forwardly-extending tabs may comprise a rearwardly extending groove which extends in a rearward direction from the post receiving slot. This groove preferably has a width narrower than the width of the adjacent portion of the post receiving slot. It preferably also has a width narrower than the width of the post portions of the rearwardly extending tabs. Where the forwardly extending tabs comprise a tab reinforcement portion, the rearwardly extending groove may also extend through the tab reinforcement portion. Providing such a groove can advantageously allow for greater flexibility of the opposing jaw parts of the forwardly-extending tabs.

The rearwardly-extending tabs of each ring link may be oppositely disposed about a circumferential edge of the respective ring link body. In other words, the rearwardly-extending tabs may be located at 1800 relative to one another about the ring link body.

In some arrangements, at least a portion of the radially outer surface of the rearwardlyextending tabs may be located radially inwardly of the radially outer surface of the ring link body to thereby provide an arcuate recess configured to receive at least part of a forwardly-extending tab of an adjacent link. In such a configuration, the forwardly-extending tab of a first ring link may be rotatable within the arcuate recess of a second ring link during bending of the articulated member.

The post portions of the rearwardly-extending tabs preferably extend in an outwardly radial direction from a tab body of the rearwardly-extending tabs. The post portions may be arranged such that they do not protrude past a radially outer surface of the ring link body. In other words, a radially outer surface of the post portions may be arranged to extend no further than a radially outer surface of the ring link body.

The opposing jaw parts of the forwardly extending tab portion of a first link, and the post portions of the rearwardly extending tabs of a second ring link are preferably configured to be pivotably connected with one another. In other words, the opposing jaw parts of the forwardly extending tab portion of a first link, and the post portions of the rearwardly extending tabs of a second ring link may together form a hinge permitting pivoting between adjacent links. The post portions of the rearwardly extending tabs may act as a pivot pin, with each forwardly-extending tab portion is rotatable about the pivot pin. The extent of pivoting possible may depend on the size and configuration of the ring link body of adjacent links.

The size and shape of the post portions is not particularly limited, although in preferred arrangements, the post portions are substantially cylindrical. This can provide for smooth pivoting motion between adjacent links, by allowing smooth rotation of the post portions within the post-receiving slots during bending of the articulated member.

Each ring link may be oriented at 90 ° about a longitudinal axis of the articulated member with respect to an immediately adjacent ring link. With such an arrangement, each subsequent pair of links along the length of the articulated member can pivot about an axis arranged at 90 ° about a longitudinal axis of the steering section with respect to the pivot axis of an immediately adjacent ring link, thereby allowing for multi-directional bending of the articulated member.

The ring link body may have a diameter of from about 6 mm up to about 13 mm. In some arrangements, the diameter of the ring link body may be 6mm or more, 7 mm or more, 8 mm or more, 9 mm or more, 10 mm or more, 11 mm or more, or 12 mm or more. In some arrangements, the diameter of the ring link body may be 13 mm or less, 12 mm or less, 11 mm or less, 10 mm or less, 9 mm or less, 8 mm or less, or 7 mm or less. A ring link body having a diameter as set out above may be particularly suited for certain applications of an imaging endoscope (e.g. for use as a gastroscope, or for use as a colonoscope). However, for other specific applications, it may be desirable for the diameter of the ring link body to be larger or smaller than the values set out above -accordingly the diameter of the ring link body is not particularly limited to the above ranges.

The ring links may be integrally formed components. That is, the forwardly-extending tabs and the rearwardly-extending tabs may be integrally formed with the ring link body. Providing the ring links as integrally formed components can reduce manufacturing complexity of the ring links.

The ring links may be formed from a polymeric material. For example, they may be formed from a material selected from the group consisting of polyesters, polyamides (e.g. nylons), acetyls and elastomers. Polymeric materials are generally cheap, are relatively facile to shape and/or mould during manufacture, and can offer good bending flexibility which may assist in the snap-fit connection of adjacent links.

In preferred arrangements, the ring links are integral, injection moulded polymeric components.

Each respective central aperture of the plurality of ring links may be at least partly aligned to thereby define a central lumen of the articulated member. One or more endoscope elements (vacuum tube etc.) may be received in this central lumen when the articulated member is assembled as part of an endoscope. For example, the central lumen of the articulated member may be designated for use to: i. conduct a flow of irrigation liquid to the distal tip, for example by being configured to receive an irrigation liquid tube; ii. conduct a flow of insufflation gas to the distal tip, for example by being configured to receive an insufflation gas tube; iii. provide suction at the distal tip; for example by being configured to receive a suction or vacuum tube; iv. conduct a surgical instrument to the distal tip.

The shape of the central aperture of each ring link is not particularly limited. In some arrangements, the central aperture may be substantially circular. In other arrangements, the central aperture may be non-circular. For example, in one preferred arrangement, the central aperture may comprise two bulb-shaped regions connected by a neck region. The neck region may be defined by locally widened regions of the ring link body. This arrangement could also be described as an 'hourglass' shaped aperture.

Where the central aperture of each ring link is non-circular, the cross-sectional shape of a central lumen of the articulated member defined by alignment of each respective central aperture of the plurality of ring links may be lobed. For example, where the central aperture of each ring link is 'hourglass' shaped, the cross-sectional shape of a central lumen of the articulated member defined by alignment of each respective central aperture of the plurality of ring links may comprise four lobes, each of the four lobes being defined between neck regions of the central apertures of adjacent ring links. The lobes may be disposed equiangularly about the articulated member. Provision of a lobed central aperture may be advantageous, as one or more components of the endoscope can be located in one or more of said lobes, and said component(s) may be less liable to move within the aperture during use, thus reducing the risk of e.g. tangling of components within the steering section during bending.

The central aperture of each ring link may have a diameter at its widest point of from about 0.5 mm to about 10mm, more preferably from about 1 mm to about 5 mm. For example, the central aperture of each ring link may have a diameter at its widest point of 1mm or more, 2mm or more, 3mm or more or 4 mm or more. The central aperture of each ring link may have a diameter at its widest point of 10mm or less, 9 mm or less, 8 mm or less, 7 mm or less or 6 mm or less. The central aperture of each ring link may have a diameter at its narrowest point of between from about 0.5 mm to about 10 mm, more preferably from about 1 mm to about 5 mm. For example, the central aperture of each ring link may have a diameter at its narrowest point of 1mm or more, 2mm or more, 3mm or more or 4 mm or more. The central aperture of each ring link may have a diameter at its narrowest point of 10mm or less, 9 mm or less, 8 mm or less, 7 mm or less or 6 mm or less. The difference between the diameter of the central aperture at its widest point and at its narrowest point may be 2 mm or less, 1 mm or less, 0.5 mm or less. Alternatively, the central aperture may be substantially circular, being substantially the same diameter when measured in any direction.

The integrated wire guide conduits may comprise apertures extending through the ring link body. Provision of the wire guide conduits as aperture can offer advantages over arrangements where the steering wires are guided by grooves or slots provided on the ring links, because the steering wires cannot be displaced from the guide conduits during use of the endoscope. The integrated wire guide conduits may be substantially cylindrical. This can help to ensure smooth movement of the steering wires within the conduits during steering.

The integrated wire guide conduits may be located in locally widened regions of the ring link body. For example, where the central aperture of each ring link comprises two bulb-shaped regions connected by a neck region, the integrated wire guide conduits may be located in the part of the ring link body immediately adjacent the neck region of the aperture. Location of the wire guide conduits in locally widened regions of the ring link body may minimise stress on the ring link body during bending of the steering section and therefore reduces the likelihood of ring link breakage.

In some arrangements, the ring link may not comprise integrated wire guide conduits.

The articulated member may comprise an outer casing. The outer casing may comprise a tube arranged to surround the plurality of ring links. Provision of an outer casing or sheath can reduce risk of inadvertent damage to the articulated member during use. Preferably the outer casing is formed from a flexible and/or elastomeric material. This can allow for relatively unimpeded bending of the articulated member, as the outer casing can stretch and/or fold as appropriate during bending. Some preferred materials include silicones and/or thermoplastic elastomers (TPE).

Further optional features of the imaging endoscope will now be discussed.

The hand controller may be configured to be releasably connectable to a base unit by means of an umbilical section. The base unit may provide electrical power, irrigation liquid and insufflation gas to the insertion section, via the umbilical section and hand controller.

The distal tip assembly may include a light source for illumination of a region of tissue of interest. Preferably, the light source includes at least one light emitting diode (LED). There may be provided at least one electrical conductor along the insertion section for providing electrical power to the light source.

The distal tip assembly may further include an imaging chip for imaging the region of tissue of interest. There may be provided at least one electrical conductor along the insertion section for providing electrical power to the imaging chip. There may be provided at least one electrical conductor for conducting electrical signals from the imaging chip to the proximal end of the insertion section. In this manner, it is possible to implement an imaging endoscope system in which there is no need for the insertion section to transmit light, whether as illumination or optical images.

The distal tip may include a distal tip housing comprising light-transmissive portion. The distal tip housing may be integrally formed from a polymeric material.

The distal tip housing may have a collar portion extending proximally of a distal end face. The collar portion may be adapted to fit over a distal end of the steering section. This is considered to be a convenient implementation.

The distal tip housing may have a cleaning nozzle arranged at the distal end face, to direct irrigation liquid to clean a lens of the imaging chip.

The insertion section may comprise at least one steering wire, fixed at or near the distal end of the insertion section, and extending along the length of the insertion section for connection to the hand controller, whereby the steering section of the insertion section is bendable for steering by application of tension to the at least one steering wire by operation of the hand controller. There may be provided such four steering wires, the four steering wires being substantially equiangularly spaced around the insertion section when viewed in cross section.

The steering wires may have sheaths each defining an axis of constrained movement for each respective steering wire. In other words, preferably the steering wires are provided as Bowden cables. Preferably, the steering wires extend through the steering section to the distal tip and the sheaths of the steering wires do not extend through the steering section. In this way, application of tension to the one or more steering wires can cause bending primarily in the steering section of the insertion section, without substantially influencing the curvature of the remaining portion of the insertion section intermediate the hand controller and the steering section.

Preferably the steering wire(s) extends through at least some of the integral wire guide conduits provided by the ring links of the steering section. As in preferred arrangements, each ring link is oriented at 90 ° about a longitudinal axis of the steering section with respect to an immediately adjacent ring link, each steering wire may therefore extend through a plurality of aligned integral wire guide conduits of alternate ring links. In this way, unwanted movement of the steering wires within the insertion section can be reduced or prevented.

Other features of the imaging endoscope, or imaging endoscopy system may be implemented as described in GB2569013 B -Imaging endoscope system and associated methods, published 9 September 2020, which is herein incorporated by reference.

Summary of the Figures

Embodiments and experiments illustrating the principles of the invention will now be discussed with reference to the accompanying figures in which: Figure 1 shows a schematic view of an imaging endoscopy system according to an embodiment of the present invention.

Figure 2 shows a perspective line drawing of part of an endoscope insertion section incorporating an articulated member according to an embodiment of the present invention.

Figure 3 shows the same part of an endoscope insertion section, with an outer casing component removed, a plurality of ring links forming part of the articulated member being visible.

Figure 4 shows a close-up view of part of the plurality of ring links seen in Fig. 3.

Figure 5 shows a perspective line drawing of a ring link of the same plurality of ring links of Figs. 3 and 4.

Figure 6 shows a different perspective line drawing of the ring link of Fig. 5.

Figure 7 shows yet another different perspective line drawing of the ring link of Figs. 5 and 6.

Figure 8 shows a view along a longitudinal axis of a plurality of connected ring links.

Detailed Description of the Invention

As set out above, the present inventors have realised a number of innovations which can reduce the overall cost and complexity of manufacture of an insertion section of an imaging endoscopy system, whilst providing suitable or improved performance in comparison to conventional endoscopes.

Aspects and embodiments of the present invention will now be discussed with reference to the accompanying figures. Further aspects and embodiments will be apparent to those skilled in the art. All documents mentioned in this text are incorporated herein by reference.

Fig. 1 shows a schematic view of an imaging endoscopy system 100 according to an embodiment of the present invention. The system includes a base unit 2 that is intended to be re-usable. Umbilical section 4 releasably connects the base unit 2 and hand controller 6 via a connector 8. Insertion section 10 has a proximal end 12 connected to the hand controller 6 and a distal end 14 for insertion into a subject. The distal end 14 has a steering section 16 and a distal tip assembly 18, which will be described in greater detail later.

The base unit 2 is operable to provide electrical power, irrigation liquid, insufflation gas and suction via the umbilical section 4 and hand controller 6 to the insertion section 10 in a manner well known in the in art. The delivery of insufflation gas, irrigation liquid and suction are controlled using mechanical valves 20 in the hand controller 6. These valves are referred to as "trumpet" type valves in view of their similarity in appearance and operation to valve keys on a trumpet. The insufflation gas, irrigation liquid and suction are supplied from a base unit at respective suitable fixed pressures. The timing of delivery and the rate of delivery to the distal end of the endoscope is then controlled by the user operating the mechanical valves at the hand controller. The valves operate in an analogue manner (allowing different flow rates of insufflation gas and irrigation liquid, for example, based on how far they are pressed by the user).

The hand controller 6 includes a steering control mechanism including first and second steering wire controls 22a, 22b, for controlling bending of the steering section 16. The first and second steering wire controls 22a, 22b are, in this arrangement, provided as first and second rotatable control wheels. The first and second steering wire controls 22a, 22b are operable by a user to apply tension to four steering wires (not shown) in order to control the bending of the steering section 16 in a known manner: rotation of the first rotatable control wheel winds a first pair of steering wires on or off a rotational drive wheel to thereby bend the steering section in a first plane, and rotation of the second rotatable control wheel winds a second pair of steering wires on or off a rotational drive wheel to thereby bend the steering section in a second plane, perpendicular to the first plane.

The steering wires (not shown) are provided as part of a Bowden cable, i.e. each wire is surrounded by a sheath defining an axis of constrained movement for each respective steering wire. The steering wires extend along the length of the insertion section 10, through the steering section 16 to the distal tip assembly 18. The sheaths of the steering wires do not extend through the steering section 16. In this way, application of tension to the steering wires can cause bending primarily in the steering section of the insertion section, without substantially influencing the curvature of the remaining portion of the insertion section intermediate the hand controller and the steering section.

The hand controller further comprises a tool insertion port 24 adapted to receive one or more surgical instruments, such as biopsy forceps.

The distal end 14 of the insertion section will now be described in greater detail, with reference to Fig. 2 and Fig. 3. Fig. 2 shows a perspective line drawing of the distal end of the insertion section incorporating an articulated member according to the present invention. Fig. 3 shows the same part of an endoscope insertion section with an outer casing component removed. The distal end of the insertion section includes the steering section 16 and the distal tip assembly 18. An outer casing component 26 is provided to encase the distal end of the insertion section.

This outer casing component may be e.g. a polymeric sheath.

The distal tip assembly 18 includes a light source (not shown) provided within a lighting and imaging housing portion 26 on the distal end face 28 of the distal tip assembly, for illumination of a region of tissue of interest. Typically this light source is an LED. At least one electrical conductor (not shown) is provided along the insertion section 10 for providing electrical power to the light source. The distal tip assembly 18 further includes an imaging chip (not shown) provided within a lighting and imaging housing portion 26 for imaging the region of tissue of interest. The imaging chip is provided in the form of a camera, with an objective lens located to collect and direct light onto the imaging chip. An electrical conductor (not shown) is provided for conducting electrical signals from the imaging chip to the proximal end 12 of the insertion section 10.

The distal tip assembly 18 has a cleaning nozzle 30 arranged at the distal end face 28, to direct irrigation liquid to clean the lighting and imaging housing portion 26 during use.

As can be seen in Fig. 3, the steering section 16 includes an articulated member comprising a plurality of ring links 32, wherein each ring link is arranged longitudinally in series along the articulated member. The specific configuration of the ring links constituting the articulated member is discussed in greater detail in relation to Figs. 4 to 8, discussed below. However, in brief, each ring link is formed as an integral, injection moulded polymeric component, comprising a body 34 and central aperture 40 (best seen in Fig. 5-7), a pair of forwardly-extending tabs 36a, b, and a pair of rearwardly extending tabs 38a, b. The pair of forwardly and rearwardly extending tabs are configured for snap-fit connection with respective forwardly and rearwardly extending tabs of adjacent ring links to facilitate multidirectional bending of the steering section 16. When connected in this manner, as shown in Fig. 3, each ring link is oriented at 90 ° about a longitudinal axis of the articulated member with respect to an immediately adjacent ring link. With such an arrangement, each subsequent pair of links along the length of the articulated member can pivot about an axis arranged at 90 ° about a longitudinal axis of the steering section with respect to the pivot axis of an immediately adjacent ring link, thereby allowing for multi-directional bending of the articulated member.

Fig. 4 shows a close-up view of part of the plurality of ring links seen in Fig. 3. Figs. 4-7 show various perspective line drawing of a ring link. Fig. 8 shows a view along a longitudinal axis of a plurality of connected ring links.

The forwardly-extending tabs 36a, 36b of each ring link are oppositely disposed about a circumferential edge of the respective ring link body, i.e. they are located at 180° relative to one another about the ring link body. A radially outer surface of the forwardly-extending tabs is contiguous with a radially outer surface of the ring link body.

Each forwardly extending tab 36a, 36b comprises opposing jaw parts 42a, 42b, with a post-receiving slot 44 being formed therebetween. The post receiving slot 44 includes a tapered lead-in portion 46 with a width narrower than a diameter of the post portions of the rearwardly extending tabs at at least one point. In this way, once a post portion of a first link enters into the post receiving slot and passes this narrowed portion, it cannot easily be removed from the slot without application of greater force.

The forwardly-extending tabs 36a, 36b are generally arcuate in shape, with each of the opposing jaw parts 42a, 42b having an arcuate form. The opposing jaw parts are tapered along their length, getting narrower in a rearwardly extending direction. This allows for some flexibility of the opposing jaw parts in a radial direction with respect to the body of each ring link during snap-fit connection of adjacent ring-links which can allow for adjacent ring links to be joined by snap fit connection even if they are slightly misaligned at the time of connection.

Each forwardly-extending tab 36a 36b also comprises a tab reinforcement portion 54, best seen in Fig. 5, which is provided as an integral, locally-thickened portion of the forwardly-extending tabs. It can be seen that the tab reinforcement portion is thicker than the opposing jaw parts 42a, 42b of the forwardly-extending tabs, and is at least the same thickness again as the thickness of the opposing jaw parts at the point that they connect to the tab reinforcement portion. The thickness of the tab reinforcement portion varies in a circumferential direction about the ring link body, with the thickness of the tab reinforcement portion at a circumferentially outer point of the tab being about 1.2 times the thickness of the locally-thickened portion at a circumferentially inner point of the tab, adjacent groove 58b.

The tab reinforcement portion comprises a post receiving surface 56 situated distal from a point of connection between each forwardly-extending tab portion and the ring link body. These tab reinforcement portions strengthen the forwardly-extending tabs, and reduce the risk of accidental damage to the tabs during snap-fit connection of the ring link to an adjacent ring link, or during bending of the articulated member.

The forwardly-extending tabs each further comprise a rearwardly extending groove 58a, 58b which extends in a rearward direction from the post receiving slot 44 formed in each tab. This groove has a width narrower than the width of the adjacent portion of the post receiving slot, and of the post portions 52 of the rearwardly extending tabs 38a, 38b. In this arrangement, it can be seen that the rearwardly extending grooves also extend through the tab reinforcement portion 56 of each tab.

The rearwardly-extending tabs 38a, 38b of each ring link (best seen in Fig. 6 and Fig. 7) are oppositely disposed about a circumferential edge of the respective ring link body, i.e. they are located at 180° relative to one another about the ring link body. A portion of the radially outer surface of the rearwardly-extending tabs is located radially inwardly of the radially outer surface of the ring link body to thereby provide an arcuate recess 39 configured to receive at least part of the opposing jaw portions of a forwardly-extending tab of an adjacent link, such that the said forwardly-extending tab is rotatable within the arcuate recess 39 during bending of the articulated member.

The post portions 52a, 52b of the rearwardly-extending tabs comprise cylindrical posts which extend in an outwardly radial direction from a tab body 53a, 53b of the rearwardly-extending tabs. The post portions are arranged such that they do not protrude past a radially outer surface of the ring link body -in the arrangement shown, the end face of the post portions is aligned with the radially outer surface of the ring link body. The post portions of the rearwardly extending tabs of one link, together with the opposing jaw parts of the forwardly extending tab portion of another link, together form a hinge permitting pivoting between adjacent links, with the post portions 52a, 52b acting as pivot pins about which each forwardly-extending tab portion is rotatable during bending of the articulated member.

Turning back to consider further features of the ring link body, it can be seen (e.g. Fig. 5) that each ring link comprises a pair of integral wire guide conduits 48a, 48b formed as cylindrical apertures extending through the ring link body, wherein each integral wire guide conduit comprises a chamfered lead-in portion 50a, 50b. The chamfered lead-in portion 50 acts as a guide during threading of the steering wires through the articulated member during assembly, meaning that less accurate alignment of the steering wires with the wire guide conduit is necessary during assembly of the device The central aperture 40 of a single ring link is best seen in Fig. 7. Here, the central aperture 40 is an 'hourglass' shaped aperture comprising two bulb-shaped regions 60a, 60b connected by a neck region 62. The neck region 62 is defined by locally widened regions of the ring link body, in which the integral wire guide conduits 48a, 48b are located. The location of the wire guide conduits in these locally widened regions of the ring link body can minimise stress on the ring link body during bending of the steering section 16 and therefore reduce the likelihood of ring link breakage.

Figure 8 shows a view along a longitudinal axis of a plurality of connected ring links. Due to the combination of the hourglass shaped central apertures of the ring links, and the fact that each ring link is oriented at 90 ° about a longitudinal axis of the articulated member with respect to an immediately adjacent ring link, two ring links 32a, 32b can be seen in Fig. 8. The cross-sectional shape of a central lumen of the articulated member defined by alignment of each respective central aperture of the plurality of ring links (including ring links 32a, 32b) comprises four lobes, 41 a, b, c, d, each of the four lobes being defined between neck regions of the central apertures of adjacent ring links. The lobes are disposed equiangularly about the articulated member, at 900 with respect to one another. One or more endoscope components may be located in this central lumen when the articulated member is assembled as part of an endoscope.

The features disclosed in the foregoing description, or in the following claims, or in the accompanying drawings, expressed in their specific forms or in terms of a means for performing the disclosed function, or a method or process for obtaining the disclosed results, as appropriate, may, separately, or in any combination of such features, be utilised for realising the invention in diverse forms thereof.

While the invention has been described in conjunction with the exemplary embodiments described above, many equivalent modifications and variations will be apparent to those skilled in the art when given this disclosure. Accordingly, the exemplary embodiments of the invention set forth above are considered to be illustrative and not limiting. Various changes to the described embodiments may be made without departing from the spirit and scope of the invention.

For the avoidance of any doubt, any theoretical explanations provided herein are provided for the purposes of improving the understanding of a reader. The inventors do not wish to be bound by any of these theoretical explanations.

Any section headings used herein are for organizational purposes only and are not to be construed as limiting the subject matter described.

Throughout this specification, including the claims which follow, unless the context requires otherwise, the word "comprise" and "include", and variations such as "comprises", "comprising", and "including" will be understood to imply the inclusion of a stated integer or step or group of integers or steps but not the exclusion of any other integer or step or group of integers or steps.

It must be noted that, as used in the specification and the appended claims, the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise. Ranges may be expressed herein as from "about" one particular value, and/or to "about" another particular value. When such a range is expressed, another embodiment includes from the one particular value and/or to the other particular value. Similarly, when values are expressed as approximations, by the use of the antecedent "about," it will be understood that the particular value forms another embodiment. The term "about" in relation to a numerical value is optional and means for example +/-10%.

Claims

Claims: 1. An imaging endoscope comprising: a hand controller; an insertion section having a proximal end connected to the hand controller and a distal end for insertion into a subject, wherein a distal tip assembly is located at the distal end of the insertion section and a steering section is located adjacent and proximal to the distal tip; wherein: the steering section is bendable for steering by operation of the hand controller, the steering section comprising: a plurality of ring links having a body and a central aperture, each ring link comprising a pair of forwardly-extending tabs comprising opposing jaw parts, and a pair of rearwardly extending tabs comprising respective post portions, wherein the opposing jaw parts of each forwardly-extending tabs have a post-receiving slot formed therebetween, the post receiving slot having a tapered lead-in portion with a width narrower than a diameter of the post portions of the rearwardly extending tabs at at least one point, such that the forwardly and rearwardly extending tabs are configured for snap-fit connection with respective forwardly and rearwardly extending tabs of an adjacent ring link; and wherein each ring link further comprises a pair of integral wire guide conduits, each integral wire guide conduit having a chamfered lead-in portion.
2. The imaging endoscope according to claim 1, wherein the pair of forwardly-extending tabs of each ring link are oppositely disposed about a circumferential edge of the respective ring link body.
3. The imaging endoscope according to claim 1 or claim 2, wherein the pair of rearwardly extending tabs of each ring link are oppositely disposed about a circumferential edge of the respective ring link body.
4. The imaging endoscope according to any one of the preceding claims, wherein each ring link is oriented at 90 ° about a longitudinal axis of the steering section with respect to an immediately adjacent ring link.
5. The imaging endoscope according to any one of the preceding claims, wherein each forwardly-extending tab is arcuate in form, and, during bending of the steering section, is rotatable within an arcuate recess provided by an adjacent ring link.
6. The imaging endoscope according to any one of the preceding claims, wherein the forwardly-extending tabs comprise a rearwardly extending groove which extends in a rearward direction from the post receiving slot, said rearwardly extending groove having a width narrower than the diameter of the post portions.
7. The imaging endoscope according to any one of the preceding claims, wherein the opposing jaw parts are tapered along their length.
8. The imaging endoscope according to any one of the preceding claims, wherein each forwardly-extending tab comprises a tab reinforcement portion.
9. The imaging endoscope according to claim 8 as dependent on claim 6, wherein the rearwardly extending groove extends through the tab reinforcement portion.
10. The imaging endoscope according to claim 8 or claim 9, wherein the tab reinforcement portion comprises a post receiving surface situated distal from a point of connection between each-forwardly extending tab portion and the ring link body.
11. The imaging endoscope according to any one of the preceding claims, wherein the post portions of the rearwardly extending tabs are configured to act as a pivot pin, such that each forwardly-extending tab portion is rotatable about the pivot pin.
12. The imaging endoscope according to any one of the preceding claims, wherein the post portions extend in a radially outward direction from a tab body of the rearwardly-extending tabs, no further than a radially outer surface of the ring link body.
13. The imaging endoscope according to any one of the preceding claims, wherein the central aperture of one or more ring links, or each ring link, comprises two bulb-shaped regions connected by a neck region.
14. The imaging endoscope according to claim 13, wherein the neck region is defined by locally widened regions of the ring link body.
15. The imaging endoscope according to claim 14, wherein the integral wire guide conduits are located in the locally widened regions of the ring link body.
16. The imaging endoscope according to any one of the preceding claims, wherein the cross-sectional shape of a central lumen of the articulated member defined by alignment of each respective central aperture of the plurality of ring links is lobed.
17. An articulated member for a steering section of an endoscope, the articulated member comprising: a plurality of ring links having a body and a central aperture, each ring link comprising a pair of forwardly-extending tabs comprising opposing jaw parts, and a pair of rearwardly extending tabs comprising respective post portions, wherein the opposing jaw parts of each forwardly-extending tab have a post-receiving slot formed therebetween, the post receiving slot having a tapered lead-in portion with a width narrower than a diameter of the post portions of the rearwardly extending tabs at at least one point, such that the forwardly and rearwardly extending tabs are configured for snap-fit connection with respective forwardly and rearwardly extending tabs of an adjacent ring link; and wherein each ring link further comprises a pair of integral wire guide conduits, each integral wire guide conduit having a chamfered lead-in portion.