Bendable tube for endoscope

Abstract

Disclosed herein is a tube for an endoscope. The tube includes a plurality of elements arranged along a centerline thereof. The elements are pivotally connected to one another by means of a plurality of joints. The joint allows the tube to bend relative to a default configuration of the tube. Each joint includes a joint head on a respective first element of the plurality of elements and a joint socket on a respective second element of the plurality of elements, wherein the joint socket is configured to receive the joint head. The joint socket and the joint head are shaped such that when the first element pivots relative to the second element from a default articulation angle of the joint associated with the default configuration to a target articulation angle, the first contact surface on the joint head engages with the second contact surface on the joint socket, the joint head is inserted into the joint socket such that the joint head is pushed outwardly out of the joint socket such that a displacement of the joint head along the centerline of the tube relative to its position at a default articulation angle is greater than zero for any target articulation angle.

Description

Technical Field

[0001] The present disclosure belongs to the field of medical technology. In particular, the present disclosure relates to a bendable tube for an endoscope, the bendable tube comprising a plurality of elements pivotably connected to each other through a plurality of joints. Background Art

[0002] An endoscope is a surgical device that can be used to access (e.g., view or remove) or treat tissue in a patient's body by inserting one or more medical tools into the patient's body through an incision on the body or a hole in the body. The endoscope may include an interface / control portion and an insertion tube coupled to the interface / control portion. The insertion tube is configured to be inserted into the patient's body and may include one or more channels to access tissue in the body. The one or more channels may, for example, be configured to receive a medical tool and / or a fluid and guide the medical tool and the fluid to the tissue of interest, respectively.

[0003] The insertion tube can be flexible so as to be inserted into the patient's body. To this end, the insertion tube can, for example, include one or more passive and / or active bendable segments (also referred to as passive bending segments and active bending segments, respectively). The passive bendable segment can, for example, be formed by a bendable or flexible material or structure that can be deformed by applying an external force. The active bendable segment can include a plurality of engagement members that can be hinged to, for example, be used for actively navigating an endoscope at the distal end of the insertion tube. Each engagement member can, for example, include a circular engagement member head that is arranged in a circular engagement member nest so that the engagement member head can pivot relative to the engagement member nest, thereby allowing the insertion tube to be bent. For example, according to WO 2018 / 029917 A1 and US2015 / 0164305 A1, it is known that there is a tube with an active bendable segment.

[0004] However, since the engagement pieces may tend to align in a zigzag pattern, wherein adjacent engagement pieces tilt in relative directions, this active bendable section may be mechanically unstable. This will not only result in reduced stability against side loads, but will also reduce the effective inner cross-sectional area of ​​the insertion tube. Due to the need to arrange a device (such as a control line) for controlling the engagement pieces, the available space inside the tube may be further reduced. In addition, it may be necessary to leave a gap between the engagement piece head and the nest to prevent the engagement piece from getting stuck. Because the gap may have to be compensated before the engagement piece transmits torque, this may cause a reduction in the transmission efficiency of torque along the tube. Summary of the invention

[0005] It is therefore a feature of the present disclosure to provide a tube for an endoscope having improved mechanical stability and efficient torque transmission while also providing sufficient space inside the tube.

[0006] The present disclosure provides a tube for an endoscope as described in the attached independent claim. Examples thereof are specified in the dependent claims.

[0007] Pipe according to the present disclosure is configured to be used for endoscope.The pipe comprises (that is, including but not limited to) a plurality of elements arranged along the center line of the pipe.These elements are pivotally connected to each other by a plurality of joints, and the plurality of joints allow the pipe to be bent relative to the default configuration of the pipe.Each joint comprises a joint head on a corresponding first element in a plurality of elements and a joint nest on a corresponding second element in a plurality of elements, wherein the joint nest is configured to receive the joint head.The shape of the joint nest and the joint head is such that when the first element is pivoted to a target articulation angle from the default articulation angle of the joint associated with the default configuration relative to the second element, the first contact surface on the joint head engages with the second contact surface on the joint nest, so that the joint head is pushed out of the joint nest, so that the displacement of the joint head relative to its position under the default articulation angle along the center line of the pipe is greater than zero for any target articulation angle.

[0008] The tube can extend from the proximal end of the tube to the distal end. As used herein, the term "proximal end" may refer to an element, feature or position that is closer to a doctor or other medical practitioner (e.g., closer to the interface / control part of the endoscope) along the length of the tube during the use of the endoscope, and the term "distal end" may refer to an element, feature or position that is closer to the position of the tissue being examined or treated in the patient's body (e.g., farther away from the interface / control part of the endoscope) along the length of the tube during the use of the endoscope. The direction along the centerline of the tube (e.g., from the proximal end to the distal end) may also be referred to as the longitudinal or axial direction hereinafter. The direction along the circumference of the tube (e.g., parallel to the surface (e.g., outer surface) of the tube and perpendicular to the longitudinal direction) may also be referred to as the circumferential or azimuthal direction. The direction perpendicular to the surface (e.g., outer surface) of the tube (e.g., perpendicular to the longitudinal and circumferential directions) may also be referred to as the radial direction. The longitudinal, circumferential and radial directions may, for example, define a cylindrical coordinate system. Depending on the state or configuration of the tube, for example, due to the bending of the tube, the orientation of these directions may change along the length of the tube.

[0009] These elements (hereinafter also referred to as tube elements) can be, for example, annular or tubular elements. These elements can, for example, have passage openings, and when these elements are connected by a joint, these passage openings can form the passage (or lumen) of pipe together. In some examples, some or all of the elements can have the same shape and / or physical size, and in particular, can be the same element (for example, made of the same material and having the same shape and physical size element). The tube element is arranged longitudinally, for example, arranged in a chain as described below. The tube element can be arranged in one or more sections along the length of pipe (that is, between the proximal end and the distal end of pipe), for example, arranged at the distal end of pipe or in an active bending section adjacent thereto. In some examples, some or all of the tube elements can be directly (that is, without any additional member or element therebetween) connected to each other via a joint. In other examples, one or more additional elements or components of the tube may be arranged between adjacent tube elements, wherein the additional elements or components may, for example, be rigidly connected between adjacent tube elements and / or may be pivotally connected between adjacent tube elements via a joint or hinge different from the joint according to the present disclosure (for example, via a joint or hinge having a circular joint head and a circular joint socket).

[0010] The centerline of a tube may extend along the center of the tube or along the center of a channel of the tube or the center of a channel arranged in the tube. The centerline may, for example, be a line or path connecting the centers (e.g., centroids) of the outer or inner peripheries of the tube along the length of the tube. Depending on the state or configuration of the tube, the centerline of the tube may not be a straight line, but may, for example, follow a curved path.

[0011] The pipe elements are pivotally connected to each other by a plurality of joints so that adjacent elements can pivot (e.g., tilt or rotate) relative to each other. Therefore, the pipe can be bent (or deformed) relative to its default configuration. The default configuration can be, for example, the configuration or state that the pipe presents in an ideal situation when a uniform tension or force (e.g., without any deviation in a certain direction) is applied along the length of the pipe (e.g., between the proximal and distal ends of the pipe). In some examples, the default configuration can be the configuration or state that the pipe presents in an ideal situation when no external tension or force is applied to the pipe (e.g., when there is no actuating device (e.g., control line) for actuating the joint. The default configuration may be associated with a predetermined bending radius that the pipe or a portion thereof presents when the pipe is in the default configuration. In particular, the default configuration can be a straight configuration (corresponding to an infinite bending radius), that is, the pipe can be straight or substantially straight in the default configuration.

[0012] Each joint piece is configured to be pivotally connected to corresponding first element (for example, corresponding proximal end or distal end element) corresponding second element (for example, respectively corresponding distal end and proximal end element).For this reason, the joint piece head on the corresponding first element can be at least partially received in the joint piece nest on the corresponding second element.The joint piece head can be, for example, a bulge or projection on the first element, which can, for example, extend longitudinally.The joint piece nest can, for example, be a corresponding incision or recess on the second element, in which the joint piece head or a part thereof can be arranged.The joint piece nest and the joint piece head respectively comprise a first contact surface and a second contact surface, which are configured to engage with each other (for example, contact each other), so as to allow the joint piece to be, for example, hinged by moving or sliding the first contact surface along the second contact surface.

[0013] In the default configuration, each joint presents a respective default articulation angle, and in some examples, presents the same default articulation angle (i.e., the default articulation angles of some or all joints may be equal, such as 0°). The articulation angle may, for example, be the angle at which the first and second elements are arranged relative to each other (e.g., the angle at which the first element is inclined relative to the second element). The default articulation angle of 0° may, for example, correspond to a configuration in which the respective first and second elements are straight or parallel to each other.

[0014] The joint socket and joint head of each joint are configured so that when the first element is pivoted relative to the second element away from the default articulation angle of the corresponding joint, the joint head is at least partially (e.g., along the longitudinal / centerline) pushed out of the joint socket. In other words, the movement of the joint head not only constitutes a rotation about a fixed rotation or articulation axis (i.e., cannot be decomposed into a pure rotation about the same rotation axis for all articulation angles), but also includes a translation outward from the joint socket.

[0015] Therefore, from the joint member nest (for example, in the reference system of the joint member nest), the joint member head is displaced from its default position (for example, along the center line) under the default articulation angle of the corresponding joint member. This may cause the first element to move or be pushed away from the second element (for example, so that the first and second elements are separated from each other or further separated), thereby causing the joint member and the pipe to extend slightly in the longitudinal direction. In other words, the joint member nest and the joint member head are configured to increase the length of the pipe (for example, the length of the center line between the proximal end and the distal end) when the joint member is pivoted away from its default articulation angle.

[0016] The shape of the joint nest and the joint head makes the displacement of the joint head along the center line relative to its position under the default articulation angle greater than zero at any target articulation angle (for example, at any articulation angle other than the default articulation angle). In other words, the displacement of the joint head (and the length of the tube) exhibits a global minimum at the default articulation angle. This can make the tube biased toward the default configuration, for example, when the tube is under uniform longitudinal tension, so that the tube preferably presents the default configuration. For example, the displacement of the joint head along the center line can be measured by projecting a line connecting the corresponding points on the joint head under the default articulation angle and the corresponding target articulation angle onto the center line. The point on the joint head can be, for example, the center of mass or mass center of the joint head or the point on the joint head through which the articulation axis of the joint extends at the default articulation. For example, the displacement can increase by 0.1 μm to 0.1 mm for every degree (°) of articulation away from the default articulation angle, increase by 0.5 μm to 50 μm in some examples, and increase by 1 μm to 10 μm in one example. The displacement of the joint at the maximum articulation angle (e.g., at one or both ends of the operable range of the joint) can be, for example, between 2μm and 1mm, in some examples between 5μm and 0.5mm, in one example between 20μm and 0.2mm, and in one example between 0.10mm and 0.15mm.

[0017] In some examples, the first contact surface includes a protrusion protruding from the inscribed circle of the first contact surface and / or the second contact surface includes a recessed portion recessed from the inscribed circle of the second contact surface. In other words, one or both of the joint head and the joint nest can be non-circular, that is, at least part of it can deviate from the circular or cross-section (for example, when viewed perpendicular to the longitudinal direction), wherein the joint head includes a protrusion relative to the circular shape, and the joint nest includes a recess relative to the circular shape. The protrusion can, for example, protrude from the inscribed circle of the first contact surface by 2% to 30% of the radius of the inscribed circle of the first contact surface, in some examples protrude by 4% to 20%, and in one example protrude by 6% to 15%. In addition or alternatively, the protrusion can, for example, protrude from the inscribed circle of the first contact surface by 5μm to 0.5mm, in some examples protrude by 20μm to 0.2mm, and in one example protrude by 0.10mm to 0.15mm. The recessed portion may be, for example, recessed from the inscribed circle of the second contact surface by 3% to 50% of the radius of the inscribed circle of the second contact surface, in some examples by 5% to 30%, and in one example by 10% to 20%. Additionally or alternatively, the recessed portion may be, for example, recessed from the inscribed circle of the second contact surface by 10 μm to 1 mm, in some examples by 30 μm to 0.3 mm, and in one example by 0.15 mm to 0.2 mm.

[0018] The inscribed circle of the contact surface used here can for example be a circle tangent to at least two non-adjacent parts (for example, the parts on the opposite sides of the joint head and the joint nest respectively) of the corresponding contact surface. The inscribed circle can be in the plane perpendicular to the pipe radial direction and / or in the plane perpendicular to the articulation axis of the joint. In some examples, the at least two non-adjacent parts can be the parts of the corresponding contact surface that contacted with another contact surface when the first element was in the default articulation angle. The inscribed circle can for example be a point on the described part of each contact surface, particularly the center of the described part of each contact surface. In one example, the inscribed circle can be the maximum circle tangent to at least two non-adjacent parts of the corresponding contact surface, wherein when the first element was in the default articulation angle, the two non-adjacent parts contacted with another contact surface.

[0019] The projections and recesses may be arranged on the respective contact surfaces so that when the first element is at the default articulation angle, the projection of the first contact surface faces the recess of the second contact surface. In other words, when the first element is at the default articulation angle, the projection on the joint head may be arranged in the recess in the joint nest. This may allow the joint head to be arranged further within the joint head than at other articulation angles.

[0020] When the first element is pivoted from the default articulation angle to the target articulation angle, the projection can engage with the second contact surface so that the joint head is pushed outward from the joint socket. For example, the projection can contact the second contact surface (e.g., its non-recessed portion), thereby forcing the joint head to further disengage from the joint socket. In other words, the non-circular shape of the joint head and the joint socket can prevent the joint from pivoting or rotating around the fixed articulation axis, and can additionally cause translation of the joint head relative to the joint socket as described above.

[0021] In some examples, the first contact surface may include a first straight portion and a second straight portion extending at an angle to the first straight portion. In addition or alternatively, the second contact surface may include a third straight portion and a fourth straight portion. As used herein, the straight portion of the contact surface may, for example, be a portion having one or two principal curvatures equal to zero (i.e., a portion that does not exhibit curvature in at least one direction, for example, a concave / convex ellipsoidal portion or a planar portion). For example, one or both of the joint head and the joint nest may have a triangle or a V-shape or a cross section, wherein a pair of straight edges or surfaces extend at an angle to each other (e.g., when viewed along the articulation axis of the joint and / or radially). The first and second straight portions of the first contact surface may be arranged so that when the first element is in a default articulation angle, the first and second straight portions each contact the corresponding straight portion (e.g., the third or fourth straight portion) of the second contact surface. For example, this may allow a line contact or a plane contact rather than a point contact to be established between the first and second contact surfaces at a default articulation angle. This may provide a firm and clear contact, particularly when considering manufacturing tolerances.

[0022] The projection of the first contact surface can be arranged between the first and second straight portions of the first contact surface. In some examples, the first and second straight portions of the first contact surface can be tangent to the inscribed circle of the first contact surface. In addition or alternatively, the recessed portion of the second contact surface can be arranged between the third and fourth straight portions of the second contact surface. In some examples, the third and fourth straight portions of the second contact surface can be tangent to the inscribed circle of the second contact surface. For example, one or both of the joint head and the joint nest can have a flat-topped triangle or a V-shaped or a cross-section with a flat or rounded tip. The flat or rounded tip can form the projection and the recessed portion of the corresponding contact surface respectively.

[0023] In some examples, the shape of the joint member nest and the joint member head is such that when the first element is pivoted from the default articulation angle to the target articulation angle, the displacement of the joint member head along the center line of the tube relative to its position at the default articulation angle increases monotonically, in one example strictly monotonically, and the target articulation angle differs from the default articulation angle by no less than 10°, in some examples no less than 20°, and in one example no less than 30°. The displacement can, for example, increase monotonically, in one example strictly monotonically, to a target articulation angle that differs from the default articulation angle by 10° to 75°, in some examples a target articulation angle that differs from 20° to 60°, and in one example a target articulation angle that differs from 30° to 50°. Additionally or alternatively, when the first element is pivoted from the default articulation angle to the maximum articulation angle of the joint member, the displacement of the joint member head can increase monotonically, in one example strictly monotonically (e.g., the displacement can increase monotonically or strictly monotonically within the entire operable range of the joint member). In other words, at any articulation angle, the displacement of the joint head (and thus the length of the tube) may decrease when pivoting the first element toward the default articulation angle, and may increase when pivoting the first element away from the default articulation angle toward the maximum articulation angle.

[0024] In some examples, the shape of the joint socket and the joint head is such that when the first element is at the default articulation angle, the tip of the joint head is separated from the joint socket by a gap. For example, the shape of the protrusion of the first contact surface and the recess of the second contact surface can be such that when the first element is at the default articulation angle, the protrusion is separated from the recess by a gap. The gap can be, for example, between 5 μm and 0.5 mm, between 10 μm and 0.1 mm in some examples, and between 40 μm and 60 μm in one example.

[0025] In some examples, the joint piece nest can be configured to enable the joint piece head to be removed from the joint piece nest along the center line of pipe. For example, the width of the opening of the joint piece nest can be greater than the maximum width of the joint piece head (for example, along the circumferential direction), so that the joint piece head can be freely moved in and out of the joint piece nest by the opening. This open joint piece geometry (wherein the joint piece head is not limited to the joint piece nest) can, for example, allow the joint piece head to leave the joint piece nest when excessive force is applied to pipe, so that the joint piece can be prevented from being damaged in some examples. During normal use (for example, when excessive force is not applied), the joint piece head can, for example, be maintained in the joint piece nest by the device (for example, control line) for actuating the joint piece, and the device can, for example, be configured to apply uniform compression tension in the longitudinal direction when not actuated.

[0026] In some examples, the joint piece nest and / or the joint piece head include a transverse mechanical stopper, which is configured to limit the movement of the joint piece head relative to the joint piece nest in a direction parallel to the hinge axis of the joint piece (for example, radially). The transverse mechanical stopper can be or include one or more transverse sidewalls of the joint piece nest, which can be arranged at the inner periphery and / or outer periphery (for example, the inner transverse sidewall and / or outer transverse sidewall of the joint piece nest) of the corresponding element. One or more transverse sidewalls can be configured to contact the joint piece head when the joint piece head moves parallel to the hinge axis to prevent the joint piece head from leaving the joint piece nest laterally. In addition or alternatively, a transverse mechanical stopper can also be provided on the joint piece head, for example, a transverse mechanical stopper extending from the joint piece head along the inner side and / or outer side of the adjacent element including the corresponding joint piece nest.

[0027] In some examples, the maximum articulation angle of one or more joints in a plurality of joints may be different from the maximum articulation angle of other joints in a plurality of joints. For example, this can allow a non-uniform curved profile to be realized, for example, a curved profile with a non-uniform bending radius (i.e., deviating from a circle). For example, a plurality of joints may include two or more groups of joints, wherein each group may have a respective maximum articulation angle (which may be associated with a respective minimum bending radius, for example). A plurality of joints may, for example, include a first group of joints (including one or more joints) with a first maximum articulation angle and a second group of joints (including one or more joints, for example, not included in all joints in the first group) with a second maximum articulation angle different from the first maximum articulation angle. The first maximum articulation angle may, for example, be 1.25 times to 10 times the second maximum articulation angle, 1.5 times to 3 times in some examples, and vice versa. The first and second maximum articulation angles may, for example, differ by 2 ° to 30 °, differ by 5 ° to 20 ° in one example. In some examples, the maximum articulation angle of a joint may vary continuously along the length of a tube. The maximum articulation angle can, for example, increase (or decrease) monotonically, and in one example, strictly increase (or decrease) monotonically along the length of the tube, for example, so that the maximum articulation angle of any given joint is greater than the maximum articulation angle of the adjacent joint at the proximal (or distal) end. For example, different maximum articulation angles can be achieved by providing angular end faces on elements extending at different angles, as described below. In other examples, all joints may have the same maximum articulation angle.

[0028] In some examples, the tube elements are arranged in a chain, such as a series arrangement, wherein each tube element (except the outermost element) is connected to the corresponding proximal element by a respective proximal joint and is connected to the corresponding distal element by a respective distal joint. In some examples, the maximum articulation angle of the outermost joint at one or both ends of the chain may be less than the other joints in the chain. For example, the maximum articulation angle of the outermost joint at one or both ends of the chain can be 10% to 70% of the maximum articulation angle of the other joints in the chain, 20% to 50% in some examples, 25% to 45% (e.g., 1 / 3) in one example, and 50% to 70% (e.g., 2 / 3) in one example. In some examples, the other joints in the chain all have the same maximum articulation angle.

[0029] For each joint in the joint, the first element may include a first angular end face, and the second element may include a second angular end face facing the first angular end face. The first and second end faces may be configured to contact each other when the joint reaches its maximum articulation angle to prevent the joint from further articulating (e.g., serving as an axial or longitudinal mechanical stop). When the joint is not at the maximum articulation angle, the first and second end faces may be spaced apart from each other to allow the joint to articulate. In the default configuration, the first and second end faces may each extend at their respective angles relative to a plane perpendicular to the centerline of the tube. The first and second angular end faces may be angled in relative directions, for example, so that the angle sign of the first angular end face is opposite to the angle sign of the second angular end face. In some examples, corresponding contact features, such as convexities or protrusions, may be arranged on the first end face and / or the second end face or formed by the first end face and / or the second end face. The contact feature may be configured to contact with the other end face (e.g., a contact feature on the other end face) when the joint reaches its maximum articulation angle, for example, to provide a clear contact point.

[0030] When the corresponding joint is in the default articulation angle, the angle between the first and second end faces associated with the outermost joint at one end or both ends of the chain can be less than the angle between the first and second end faces associated with other joints in the chain. The angle between the first and second angled end faces in the default configuration can define (e.g., correspond to) the maximum articulation angle. The angle between the first end face associated with other joints in the chain and the second end face can be, for example, between 25° and 55°, and in one example between 35° and 45°. The angle between the first and second end faces associated with the outermost joint at one end or both ends of the chain can be, for example, between 5° and 45°, and in one example between 5° and 20° (e.g., 1 / 3 of the angle between the first and second end faces associated with other joints), and in one example between 25° and 35° (e.g., 2 / 3 of the angle between the first and second end faces associated with other joints).

[0031] In some examples, some or all of the tube elements include a guide element configured to guide a control line for actuating the plurality of engagement members. The guide element may be or include, for example, a groove, notch, clip, hook, and / or hole in which the control line may be arranged.

[0032] In some examples, pipe can also include control line, wherein control line can be arranged in the described guide element of pipe element.Control line can for example be configured to apply compressive tension to pipe or its part (particularly comprising the segment of pipe element) longitudinally (for example from the distal end to the proximal end) when actuated.Control line can for example be connected or attached to the distal end attachment point, and this distal end attachment point can for example be arranged at the distal end side of pipe element, for example, be located at or adjacent to the distal end or tip of pipe.When the near end of control line is pulled, the force from the distal end attachment point towards the near end of pipe can be generated.In some examples, control line can also be configured to also apply compressive tension when not actuated, for example, to make pipe offset towards default configuration and / or to fix the joint head in the joint nest.

[0033] The guide element may for example be arranged at the periphery of the respective element, for example on the outer surface of the element facing away from the central opening of the element (i.e. radially outwards as seen from the center line of the pipe). In particular, the guide element may be arranged such that when the control line is arranged in the guide element, the control line is located outside the pipe, i.e. not in or facing the central opening. This may, for example, increase the available space in the pipe.

[0034] In one example, the guiding element is configured to guide the control line so that the control line is arranged to be adjacent to the medial or lateral side of the joint head on the corresponding element or the adjacent element. The guiding element can for example align with the joint head or the joint nest on the corresponding element in a circumferential direction, for example, when the control line is arranged in the guiding element, it extends near the corresponding joint, for example, passes or is adjacent to the actuating shaft of the joint. The control line arranged adjacent to the medial or lateral side of the joint head can for example provide a horizontal mechanical stopper for the corresponding joint head, for example, to prevent the joint head from leaving the joint nest radially.

[0035] In some examples, each of some or all of the elements is pivotally connected to a corresponding first adjacent element (e.g., a corresponding proximal element) by a corresponding first pair of engagement members arranged on the opposite side of the pipe. The first pair of engagement members can be, for example, displaced 150 ° to 210 ° relative to each other along a circumferential direction, 170 ° to 190 ° in one example. In some examples, some or all of the engagement members in the first pair of engagement members can be arranged in the same plane, for example, to allow the pipe to be bent in a first articulation direction or in a first articulation plane.

[0036] In addition or alternatively, some or all of the elements (particularly some or all of the elements pivotably connected to the corresponding first adjacent element by the corresponding first pair of engagement pieces) are each pivotably connected to the corresponding second adjacent element (for example, the corresponding distal element) by the corresponding second pair of engagement pieces arranged on the opposite side of the pipe. The second pair of engagement pieces can be, for example, displaced 150 ° to 210 ° relative to each other along the circumferential direction, 170 ° to 190 ° in one example. In some examples, some or all of the engagement pieces in the second pair of engagement pieces can be arranged in the same plane, for example, to allow the pipe to be bent in the second articulation direction or in the second articulation plane.

[0037] The first and second pairs of engagement members can be displaced relative to each other along the circumferential direction of the tube by 75° to 105°, in some examples by 80° to 100°, and in one example by 85° to 95° (e.g., 90°). In other words, on each respective tube element, the engagement member heads and / or engagement member nests associated with the respective first and second pairs of engagement members can be arranged alternately and equidistantly or substantially equidistantly in the circumferential direction, for example, staggered by 90° with adjacent engagement member heads and / or engagement member nests. Thus, the first and second articulation directions / planes can be orthogonal or substantially orthogonal to each other.

[0038] Some or all of the pipe elements pivotably connected to the corresponding adjacent elements by the first and second pairs of engagement pieces can each include four guiding elements arranged along the circumference of the corresponding element, and each of the four guiding elements is configured to guide the corresponding control line. Each of the four guiding elements can be staggered 35 ° to 55 ° with the adjacent engagement piece along the circumferential direction of the pipe, and in some examples, 40 ° to 50 ° (for example 45 °). In other words, each of the guiding elements can be arranged at about half of the two engagement pieces associated with the corresponding pipe element (that is, between the corresponding first pair of engagement pieces and the corresponding second pair of engagement pieces). In some examples, two of the guiding elements can be arranged in the first line plane, and the other two guiding elements can be arranged in the second line plane. The angle between the first and second line planes and the first and second articulation planes can be between 35 ° and 55 °, and in some examples, between 40 ° and 50 ° (for example 45 °). Because the line plane is not aligned with the articulation direction / plane, actuating each control line may actuate all engagement pieces simultaneously. This may cause, for example, the pipe to be bent in the corresponding line plane.

[0039] In other examples, each of the four guide elements may be aligned with a corresponding engagement member in a circumferential direction, for example, such that the line plane is aligned with the articulation direction / plane. In this case, actuating each control line may actuate only the first pair of engagement members or the second pair of engagement members and may result in bending the tube in the corresponding articulation direction / plane.

[0040] Each tube element can extend around a corresponding passage opening as described above, for example, so that the side wall of each tube element surrounds or surrounds the corresponding passage opening in a circumferential direction. The passage opening can have a circular or substantially circular cross-section perpendicular to the centerline of the tube. For example, the diameter of the passage opening can vary less than 25% (e.g., between 0% and 25%, between 5% and 25% in some examples, between 10% and 25% in one example), preferably less than 15%, and less than 10% in one example. The diameter variation of the passage opening can be defined, for example, as the ratio of the difference between the maximum diameter and the minimum diameter of the passage opening to the average diameter. The tube element can have a smooth inner surface along its inner circumference. For example, in a plane perpendicular to the centerline, the minimum radius of curvature of the inner surface can be no less than 10% (e.g., between 10% and 100%) of the average radius of the channel opening, in some examples no less than 20% (e.g., between 20% and 100%), in one example no less than 30% (e.g., between 30% and 100%), and in one example no less than 40% (e.g., between 40% and 100%).

[0041] The tube according to the present disclosure is configured for use with an endoscope. The tube may be configured, for example but not limited to, for use with a bronchoscope, sinusoscope, nasopharyngoscope, laryngoscope, laparoscope, gastroscope, duodenoscope, colonoscope, ultrasound endoscope, hysteroscope, cystoscope, uroscope, urethroscope, cardioscope, and arthroscope. The length, diameter, and / or stiffness / flexibility of the tube may be selected accordingly.

[0042] The tube can be, for example, an insertion tube for an endoscope or a portion of an insertion tube for an endoscope. In one example, the tube is a hypotube for an endoscope. The hypotube can, for example, be configured to be surrounded or enclosed by a tubular sleeve or cover to form an insertion tube. The hypotube can, for example, form a frame or skeleton of the insertion tube, which is configured to provide dimensional stability to the insertion tube.

[0043] The present disclosure also provides an endoscope, comprising a tube according to any example described herein. The tube may be, for example, an insertion tube of an endoscope or a part thereof, in particular a hypotube. The endoscope may also include an interface / control unit configured to be coupled to the tube. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] The present disclosure and its examples are described in detail below with reference to the accompanying drawings. These drawings show the following schematic diagrams:

[0045] Figure 1 : An endoscope according to an example of the present disclosure;

[0046] Figure 2a : A joint having a joint head and a joint socket according to an example of the present disclosure;

[0047] Figure 2b : Default articulation angle Figure 2a The joint parts;

[0048] Figure 2c : At the first target articulation angle Figure 2a The joint parts;

[0049] Figure 2d : The second target articulation angle Figure 2a The joint parts;

[0050] Figure 3a : A pair of tube elements having a joint head and a joint socket according to an example of the present disclosure in a side view;

[0051] Figure 3b : Close-up view Figure 3a The joint head and the joint socket of the pipe element;

[0052] Figure 3c : Front view Figure 3a one of the pipe elements;

[0053] Figure 3d : Rear view Figure 3a one of the pipe elements;

[0054] Figure 3e : In perspective Figure 3a one of the pipe elements;

[0055] Figure 4a : A first side view of an active bending section of a tube for an endoscope according to an example of the present disclosure;

[0056] Figure 4b : Figure 4a A second side view of the active bending segment;

[0057] Figure 5a : A side view of a pair of pipe elements having a joint head and a joint socket according to another example of the present disclosure;

[0058] Figure 5b : In perspective Figure 5a one of the pipe elements;

[0059] Figure 5c : Front view Figure 5a one of the pipe elements;

[0060] Figure 5d : Rear view Figure 5a one of the pipe elements;

[0061] Figure 5e : In another perspective Figure 5a one of the pipe elements;

[0062] Figure 6a : An active bending section of a tube for an endoscope according to another example of the present disclosure in a first side view; and

[0063] Figure 6b : Second side view Figure 6a Active bending section. DETAILED DESCRIPTION

[0064] Figure 1 A schematic diagram (not drawn to scale) of an endoscope 100 according to an example of the present disclosure is shown. The endoscope 100 includes an interface / control portion 102 having a connector 104 and one or more ports 106 .

[0065] The connector 104 is configured to connect or attach the tube 200 to the interface / control portion 102, wherein in some examples, the tube 200 may be removably connected or attached. The tube 200 extends from a proximal end 200A to a distal end 200B along a centerline 201 of the tube 200, wherein the proximal end 200A is adjacent to the interface / control portion 102 (e.g., connected or attached to the interface / control portion 102 via the connector 104), and the distal end 200B faces away from the interface / control portion 102. The direction X along the centerline 201 from the proximal end 200A to the distal end 200B may be referred to as the longitudinal, axial, or X direction hereinafter. The direction φ along the circumference of the tube (e.g., parallel to the surface of the tube and perpendicular to the longitudinal direction X) may be referred to as the circumferential, azimuthal, or φ direction hereinafter.

[0066] The one or more ports 106 may, for example, include one or more fluid ports in fluid communication with the interior of the tube 200, such as in fluid communication with a channel (not shown) formed by or disposed in the tube 200, such as via the connector 104. Additionally or alternatively, the one or more ports 106 may include one or more light guide ports, wherein each light guide port may, for example, be configured to receive a light guide (not shown) to be disposed within the tube 200 and / or provide coupling with a light guide (not shown) disposed within the tube 200 (e.g., disposed in a channel formed by or disposed in the tube 200). The interface / control portion 102 may also include one or more electrical contacts (not shown), for example, to provide electrical connection with the interior of the tube 200, the distal end 200B of the tube 200, and / or a distal tip (not shown) of the endoscope 100, which may, for example, be disposed at or connected to the distal end 200B of the tube 200. The interface / control portion 106 may also include a device for actuating the distal segment 200-II of the tube 200, such as one or more control knobs (not shown), which may be configured to apply tension to one or more control lines (not shown) coupled to the distal segment 200-II via one or more attachment points at the distal end 200B.

[0067] The interface / control unit 102 may be implemented as follows Figure 1 The single unit shown may be realized as two or more separate units, such as a control part, which may be connected to the proximal end 200A of the tube 200, for example via connector 104, and an interface part, which may be connected to the control part, for example via a flexible tube or umbilical cord.

[0068] Tube 200 may be a tube for an endoscope according to any of the examples described herein. Figure 1In the example of the embodiment of the present invention, the tube 200 includes a first or proximal segment 200-I and a second or distal segment 200-II. The proximal segment 200-I can be or include one or more passive bending segments (not shown), which are configured to bend or deform when an external force is applied. The passive bending segment can be made of (for example, including) a flexible material. In addition or alternatively, the passive bending segment can be made of a rigid or semi-rigid material, such as a metal (for example, stainless steel), and can, for example, include a plurality of bendable segments, wherein in each bendable segment, one or more openings can be provided in the wall of the tube 200 to increase the flexibility of the tube 200 in the corresponding bendable segment. In some examples, the proximal segment 200-I can also include, for example, a rigid segment (not shown) at the proximal end 200A adjacent to the connector 104, as a supplement or replacement for one or more passive bending segments. The length and diameter of the tube can be selected to suit the type of endoscope with which the tube 200 will be used. The length of the tube 200 can be, for example, between 20 cm and 200 cm, and in some examples between 50 cm and 150 cm. The outer diameter of tube 200 may be, for example, between 1 mm and 20 mm, and in some examples between 2 mm and 10 mm.

[0069] exist Figure 1 In the example of the embodiment of the present invention, the distal segment 200-II is or includes a bending segment, in particular an active bending segment, and therefore may also be referred to as an active bending segment 200-II. The active bending segment 200-II includes a plurality of elements 202 (hereinafter also referred to as tube elements 202) arranged along the centerline 201 of the tube 200. The tube elements 202 are pivotally connected to each other by a plurality of joints 204 to allow the tube 200 (in particular the active bending segment 200-II) to bend relative to the default configuration of the tube 200. The default configuration may be, for example, Figure 1 The straight configuration shown, in which the tube 200 is not bent and the centerline 201 is a straight line. The default configuration can be, for example, the configuration that the tube 200 presents in an ideal situation (e.g., without any external disturbance) when no additional tension is applied to the control line, for example, so that the control line produces a uniform (non-directional) compressive tension in the longitudinal direction. In some examples, the active bending segment 200-II can be actively actuated or controlled (e.g., using a corresponding device (e.g., a control line) for actuating the active bending segment 200-II). In other examples, the segment 200-II can be a passive bending segment, wherein the passive bending segment can bend or deform, for example, under the action of an external force that causes the joint to pivot.

[0070] Each joint 204 is configured such that when the elements 202 connected by the respective joint 204 are moved relative to each other from a default articulation angle of the joint 204 associated with the default configuration (e.g., Figure 1 ) to a target articulation angle different from the default articulation angle (ie, Figure 1The joint 204 is extended or expanded in the longitudinal direction to slightly increase the length of the tube 200 in the longitudinal direction, for example, as described below with reference to Figure 2a to Figure 2d Each joint member 204 can be implemented as Figure 2a to Figure 2d The joint parts Figure 3a , Figure 3b The joint or Figure 5a In the default configuration, the tube 200 (e.g., its centerline 201) may have its smallest longitudinal extent, i.e., the smallest length in the longitudinal direction. When a uniform tension is applied in the longitudinal direction, the tube 200 may tend to reduce or minimize its length and may assume the default configuration, i.e., Figure 1 Straightening in the example.

[0071] Figure 2a to Figure 2d A schematic diagram (not drawn to scale) of a coupling 204 for a tube of an endoscope according to an example of the present disclosure is shown. The coupling 204 may be used, for example, Figure 1 The tube 200 is provided to pivotally connect the two elements 202 to each other. Hereinafter, the tube 200 will be used as a non-limiting example for illustrative purposes. Figure 2a to Figure 2d The viewing direction in can be parallel to the articulation axis of the joint 204 and can correspond, for example, to the radial direction of the tube 200 .

[0072] The joint 204 includes a joint head 204B on a corresponding first element 202B (e.g., a distal element of the joint 204 closer to the distal end 200B of the tube 200) and a joint socket 204A on a corresponding second element 202A (e.g., a proximal element of the joint 204 closer to the proximal end 200A of the tube 200). The joint socket 204A is configured to receive the joint head 204B, such as Figure 2a to Figure 2d As shown. Figure 2a In FIG. 2 , for example, when the tube 200 is assembled, the fastener 204 is depicted with the fastener head 204B removed from the fastener socket 204A. Figure 2b to Figure 2d In FIG. 2 , a joint 204 is depicted, wherein a joint head 204B is disposed in a joint socket 204A. Figure 2b In FIG. 2 , the joint 204 is at its default articulation angle, for example, 0° in this example, corresponding to the straight centerline 201, and in FIG. Figure 2c and Figure 2d In the embodiment, the joint member 204 is respectively at the first and second target articulation angles different from the default articulation angle, for example, Figure 2c In the example, it is 10° and Figure 2d Therefore, the center line 201 is at Figure 2c and Figure 2d bend or kink in the middle.

[0073] The joint head 204B includes a first contact surface 206B, which is configured to slidably engage with a second contact surface 206A on the joint socket 204A when the joint head 204B is received in the joint socket 204B. The shapes of the joint socket 204A and the joint head 204B, and in particular the first and second contact surfaces 206A, 206B, are such that when the first element 202B is pivoted relative to the second element 202A away from the default hinge angle, for example, from Figure 2b The default configuration becomes Figure 2c The first contact surface 206B is engaged with the second contact surface 206A so that the joint head 204B is pushed outwardly toward the joint socket 204A. Figure 2b The joint head 204B and the joint socket 204A are configured such that the displacement D is greater than zero at any target articulation angle (e.g., any non-zero articulation angle), i.e., the joint 204 (and the tube 200) has its minimum longitudinal extent at the default articulation angle.

[0074] exist Figure 2a to Figure 2d In the example of the joint member, the joint member socket 204A and the joint member head 204B both have a non-circular cross-section perpendicular to the articulation axis of the joint member 204 (e.g., perpendicular to the radial direction of the tube 200). In particular, the first contact surface 206B of the joint member head 204B includes a protrusion 208B protruding from the inscribed circle 210B of the first contact surface 206B. The second contact surface 206A of the joint member head 204A includes a recessed portion 208A recessed from the inscribed circle 210A of the second contact surface 206A. Figure 2a to Figure 2d In the example of FIG. 1 , the inscribed circles 210A, 210B are perpendicular to the hinge axis of the joint 204 and are defined such that the portion of the corresponding contact surface 208A, 208B in contact with the other contact surface 208B, 208A at the default hinge angle is tangent to the inscribed circles 210A, 210B, as shown in FIG. Figure 2b As shown. At the default articulation angle, the center 212A of the inscribed circle 210A of the second contact surface 206A can be aligned with the center 212B of the inscribed circle 210B of the second contact surface 206B. The centers 212A, 212B can, for example, be located on the articulation axis of the joint 204 at the default articulation angle. The inscribed circles 210A, 210B can, for example, be the largest circle that can be inscribed with the first and second contact surfaces 206A, 206B, respectively, and are centered on the articulation axis of the joint 204 at the default articulation angle.

[0075] Under the default articulation angle, the protrusion 208B faces the recessed portion 208A and is separated from the recessed portion 208A by a gap 214. The width of the gap 214 along the longitudinal direction can be, for example, between 10 μm and 100 μm. When the first element 202B pivots away from the default articulation angle, the protrusion 208B contacts the second contact surface 206A, for example, contacts the lateral portion of the adjacent recessed portion 206A. This causes the joint head 204B to be pushed outwardly from the joint nest 204A, so that the joint head 204B staggers the displacement D along the center line 201. The displacement D can be, for example, the distance that the center 212B of the inscribed circle 210B of the first contact surface 206B is staggered from the center 212A of the inscribed circle 210A of the second contact surface 206A. In some examples, the displacement D can increase monotonically with the articulation angle, for example, monotonically with the modulus of the difference between the target articulation angle and the default articulation angle. The displacement D can increase monotonically within a range of articulation angles (e.g., up to at least 20° of articulation angle, and in some examples at least 30°) and / or within the entire operable range of the joint 204 (e.g., up to the maximum articulation angle of the joint 204).

[0076] When the first element 202B is pivoted, the movement of the joint head 204B corresponds to the rotation and translation of the combination. This movement causes the first element 202B to rotate or tilt, thereby causing the corresponding portion of the centerline 201 to rotate or tilt the articulation angle, and causes the displacement of the joint head 204B. Thus, when the first element 202B is pivoted, the articulation axis of the joint 204 may shift, and may be in different positions at each articulation angle. The articulation axis may not tilt, but can always remain parallel to its orientation at the default angle (that is, it can be shifted or translated by parallel offset), for example, parallel to the radial direction.

[0077] Figure 3a A schematic diagram of a pair of tube elements 202A, 202B having a joint socket 204A and a joint head 204B, respectively, is depicted in side view according to an example of the present disclosure. The tube elements 202A, 202B can be used, for example, Figure 1 The tube 200 will be used hereinafter as a non-limiting example for illustrative purposes. Figure 3b Shown with Figure 3a A close-up view of the joint member socket 204A and the joint member head 204B corresponding to the dashed rectangle in FIG. Figure 3c and Figure 3d , one of the tube elements 202A, 202B is shown in a front view (eg, along the longitudinal direction of the tube 200 facing the proximal end 200A) and a rear view (eg, along the longitudinal direction of the tube 200 facing the distal end 200B), respectively. Figure 3e One of the tube elements 202A, 202B is depicted in perspective.

[0078] The tube elements 202A, 202B may be made of (e.g., include, i.e., include but are not limited to) a semi-rigid or rigid material, in particular a metal, such as stainless steel, titanium, or a nickel-titanium alloy (such as Nitionol). In some examples, the tube elements 202A, 202B may be made of (i.e., in addition to) a semi-rigid or rigid material, in particular a metal, such as stainless steel, titanium, or a nickel-titanium alloy (such as Nitionol).

[0079] The joint socket 204A is configured to receive the joint head 204B to form the articulated joint 204. Figure 2a to Figure 2d Similar to the joint of the embodiment of the present invention, the joint head 204B includes a first contact surface 206B having a protrusion 208B protruding from an inscribed circle 210B of the first contact surface 206B. The joint socket 204A includes a second contact surface 206B configured to slidably engage with the first contact surface 206A to allow the joint 204 to articulate. The second contact surface 206A includes a recessed portion 208A recessed from the inscribed circle 210A of the second contact surface 206A.

[0080] exist Figure 3a , Figure 3b In the example of , the first contact surface 206B has a flat-topped triangle or V-shape (e.g., a flat-topped triangle or V-shaped profile or shape in a plane perpendicular to the hinge axis of the joint 204). The first contact surface 206B includes a pair of straight portions 206B-I, 206B-II arranged on opposite sides of the protrusion 208B. The second contact surface 206A has a corresponding flat-topped triangle or V-shape, and also includes a pair of straight portions 206A-I, 206A-II arranged on opposite sides of the recessed portion 208A. Each of the straight portions 206A-I, 206A-II, 206B-I, 206B-II is tangent to the inscribed circle 210A, 210B of the corresponding contact surface 206A, 206B. The inscribed circles 210A and 210B may, for example, extend through the centers of the corresponding straight portions 206A-I, 206A-II, 206B-I, and 206B-II. Figure 3b When the joint head 204B is at the default articulation angle (e.g., Figure 3a , Figure 3b When the straight portions 206A-I, 206A-II, 206B-I, 206B-II are received in the joint member nest 204A at 0° in the configuration shown, they can contact each other. This can provide a firm and clear contact between the joint member nest 204B and the joint member head 204A.

[0081] The first element 202A and the second element 202B each include a first angled end face 302A and a second angled end face 302B, respectively. The end faces 302A, 302B face each other and are configured to contact each other when the joint 204 reaches its maximum articulation angle, thereby preventing further articulation of the joint 204. The maximum articulation angle may correspond, for example, to the angle between the end faces 302A, 302B when the joint is at a default articulation angle, and may be, for example, between 5° and 75°, between 25° and 55° in some examples, and between 35° and 45° in one example.

[0082] The pipe elements 202A, 202B are annular elements extending around (e.g., around or surrounding) the passage opening 300 in a circumferential direction. In some examples, the pipe elements 202A, 202B can be identical elements, wherein the second element 202A can be, for example, rotated 90° relative to the first element 202B in a circumferential direction. Each of the pipe elements 202A, 202B can include a pair of engagement piece heads 204B on a first end face (e.g., a proximal end face) and a pair of engagement piece nests 204A on a second end face (e.g., a distal end face) opposite to the first end face. The engagement piece nests 204A can be arranged on opposite sides of the pipe element in a circumferential direction, for example, rotated 180° relative to each other in a circumferential direction. The joint head 204B may also be arranged on opposite sides of the pipe element along the circumferential direction, for example, rotated 180° relative to each other along the circumferential direction, for example, so that the joint socket 204A and the joint head 204B are equally spaced apart along the circumferential direction (for example, spaced apart by 90°), as shown in FIG. Figure 3c to Figure 3e shown.

[0083] Each tube element 202A, 202B further includes four guide elements 304A, 304B, wherein each guide element is configured to guide a control wire to actuate the active bending section 200-II of the tube 200. Each guide element 304A, 304B is arranged at the periphery of the corresponding tube element 202A, 202B and includes a groove and a hole in which the corresponding control wire can be arranged. The first pair of guide elements 304A is arranged adjacent to a corresponding one of the joint sockets 204A, for example, Figure 3c to Figure 3e As shown, the second pair of guide elements are aligned with the corresponding engagement member socket 204A in the circumferential direction. The second pair of guide elements are arranged adjacent to a corresponding engagement member head 204B, for example, Figure 3c to Figure 3e As shown, they are aligned with the corresponding engagement member heads 204B in the circumferential direction.

[0084] Figure 4a , 4b A schematic diagram of an active bending section 200 - II of a tube for an endoscope is depicted according to an example of the present disclosure. Figure 4a The active bending section 200-II is shown in a first side view, Figure 4bThe active bending section 200-II is shown in a second side view, which can be, for example, Figure 4a The viewing direction is orthogonal.

[0085] The active bending segment 200-II can be, for example, a distal segment 200-II of the tube 200 or can form a part thereof. Therefore, the tube 200 will be used as a non-limiting example for illustrative purposes below. The active bending segment 200-II connects the proximal segment 200-I of the tube 200 with the tip of the tube 200 at the distal end 200B, wherein the tip of the tube 200 can be formed, for example, by the outermost distal element 402B of the active bending segment 200-II. The active bending segment 200-II can allow active navigation of the tip of the tube 200, for example using a control device provided in the interface / control portion 102, such as a control knob.

[0086] To this end, the active bending section 200-II includes a plurality of elements 202A, 202B, 402A, 402B, some or all of which (e.g., all elements 202A, 202B arranged between the outermost elements 402A, 402B) may be implemented, for example, as Figures 3a to 3e The active bending section 200-II may include, for example, 3 to 50 elements, and in some examples, 5 to 20 elements, such as Figure 4a , Figure 4b The elements 202A, 202B are arranged in a chain, wherein each element 202A, 202B (except the outermost elements 402A, 402B) is pivotally connected to the corresponding proximal element by a pair of proximal joints 204, and is pivotally connected to the corresponding distal element by a pair of distal joints 204, each joint 204 being formed by a joint socket 204A and a joint head 204B, as described above with reference to Figure 2a to Figure 2d , Figures 3a to 3e described.

[0087] exist Figure 4a , 4b In the example of FIG. 1 , the joints 204 are arranged in two articulation planes, wherein every other pair of joints along the chain (e.g., the first, third, fifth, ... pairs of joints along the chain, in FIG. 1 ) are arranged in two articulation planes. Figure 4b As can be seen in FIG. 1 , also referred to as the first set of engaging members) are arranged in the first hinge plane, and the remaining engaging members (e.g., the second, fourth, ... pairs of engaging members, in Figure 4a202A, 202B, a pair of proximal engagement members 204 are displaced 90° along the circumferential direction relative to a pair of distal engagement members 204. Each set of engagement members is configured to allow the active bending segment 200-II to articulate in a direction or plane perpendicular to the corresponding articulation plane.

[0088] As mentioned above Figure 3c to Figure 3e As described, the guide elements 304A, 304B on the tube elements 202A, 202B are aligned with one of the joints 204, so that when the control lines are arranged in the guide elements 304A, 304B, they extend in two line planes aligned with the hinge plane, thereby allowing actuation of the group of joints associated with the hinge plane perpendicular to the line plane in which the corresponding lines are arranged (thereby causing the active bending section 200-II to bend in the line plane in which the corresponding line plane is arranged).

[0089] Except outermost element 402A, 402B, all tube elements 202A, 202B can be identical element, wherein every other element rotates 90 ° along circumferential direction (makes joint piece nest 204A and the joint piece head 204B on adjacent element align, to form joint piece 204). Outermost proximal element 402A can be configured to be connected or attached to proximal section 200-I, and outermost distal element 402B can form the distal tip of pipe 200, and can for example be configured to accommodate camera and / or one or more medical tools. Outermost distal element 402B can also include one or more attachment points, and corresponding control line can be connected or attached to outermost distal element 402B at this one or more attachment points.

[0090] Outermost elements 402A, 402B are also different from other elements 202A in that their end faces 406A, 406B are at different angles relative to a plane perpendicular to the centerline 201 of the tube 200. In particular, end faces 406A, 406B extend at a smaller angle relative to the plane than the end face of another element 202A. Thus, the angle between each of end faces 406A, 406B and the opposite end face of the corresponding adjacent element 202A, 202B (and therefore the maximum articulation angle of the outermost joint 404) is less than the angle between the opposite end faces of the elements 202A, 202B (and therefore the maximum articulation angle of the joint 204). For example, the angle between the opposite end faces of the elements 202A, 202B can be between 35° and 45°, for example 40°. The angle between each of the end faces 406A, 406B and the opposite end face of the corresponding adjacent element 202A, 202B can be, for example, between 25° and 35°, for example, 30° in one example, or 2 / 3 of the angle between the opposite end faces of the elements 202A, 202B in another example. In other examples, the angle between each of the end faces 406A, 406B and the opposite end face of the corresponding adjacent element 202A, 202B can be between 5° and 20°, for example, 15° in one example, or 1 / 3 of the angle between the opposite end faces of the elements 202A, 202B in another example.

[0091] Figure 5a A schematic diagram of a pair of pipe elements 202A, 202B having a joint socket 204A and a joint head 204B, respectively, according to another example of the present disclosure is depicted in side view. The pipe elements 202A, 202B can be used, for example, Figure 1 The tube 200 will be used hereinafter as a non-limiting example for illustrative purposes. Figure 5b and Figure 5e One of the tube elements 202A, 202B is depicted in two different perspective views. Figure 5c and Figure 5d , one of the tube elements 202A, 202B is shown in a front view (eg, along the longitudinal direction of the tube 200 facing the proximal end 200A) and a rear view (eg, along the longitudinal direction of the tube 200 facing the distal end 200B), respectively.

[0092] Tube elements 202A, 202B and Figures 3a to 3e In particular, the tube elements 202A, 202B are also annular elements, including a pair of flat-topped triangular or V-shaped engagement member heads 204B on a first (e.g., proximal) end face and a corresponding pair of flat-topped triangular or V-shaped engagement member sockets 204A on a second (e.g., distal) end face, such as Figure 3b shown.

[0093] Tube elements 202A, 202B and Figures 3a to 3e The tube element of 204A and 204B differs in the arrangement of the guide element 304 relative to the joint head and the sockets 204A, 204B. Figure 5a to Figure 5e In the example of FIG. 1 , the guide elements 304 are displaced relative to the joint head and the socket 204A, 204B so that each guide element 304 is arranged between the corresponding joint head 204B and the corresponding joint 204A, for example, halfway between the joint head 204 and the joint socket 204A (staggered 45° from the joint head 204B and the joint socket 204A, respectively, in the circumferential direction). For example, this can allow the formation of a tube element chain in which the articulation plane of the joint 204 and the line plane of the control line are not aligned, for example, as described below with reference to FIG. Figure 6a , Figure 6b described.

[0094] The tube elements 202A, 202B further include a transverse mechanical stop 500 configured to limit movement of the joint head 204B relative to the corresponding joint socket 204A in a direction parallel to the joint's articulation axis (eg, in a radial direction). Figure 5a to Figure 5e In the example of FIG. 5 , the transverse mechanical stop 500 is a side wall of the engagement member pocket 204A arranged at the inner periphery of the corresponding pipe element 202A, 202B. For example, the side wall can extend in the entire depth of the corresponding engagement member pocket along the longitudinal direction, for example, as Figure 5a In some examples, the sidewall can include a tip portion, such as a rounded tip portion, configured to engage a corresponding contact surface on an adjacent tube element 204A / B.

[0095] Figure 6a , Figure 6b A schematic diagram of an active bending section 200 - II of a tube for an endoscope according to another example of the present disclosure is depicted. Figure 6a A first side view of the active bending section 200-II is shown, Figure 6b A second side view of the active bending section 200-II is shown, which can be, for example, Figure 6a The viewing direction is orthogonal.

[0096] Active bending section 200-II and Figure 4a , Figure 4b The active bending section of the embodiment of the present invention also includes a chain of pipe elements 202A, 202B, 402A, 402B, which are pivotally connected to each other by a plurality of articulated joints 204, 404, which are formed by joint heads 204A and joint sockets 204B on the pipe elements 202A, 202B, 402A, 402B. Except for the outermost elements 402A, 402B, each element 202A, 202B can be implemented, for example, as Figure 5a to Figure 5e The elements 202A, 202B are arranged such that adjacent elements are rotated 90° relative to each other in the circumferential direction.

[0097] like Figure 4a , Figure 4b As shown in the example of FIG. 2 , the joints 204 are arranged in two articulated planes. Every other pair of joints on the chain (e.g., the first, third, fifth, ... pairs of joints, also referred to as the first group of joints) are arranged on the first articulated plane (relative to the first pair of joints). Figure 6a The viewing direction is tilted +45° relative to Figure 6b The remaining joint members (e.g., the second, fourth, ... pairs of joint members, also referred to as the second group of joint members) are arranged in a second articulation plane orthogonal to the first articulation plane (relative to Figure 6a The viewing direction is tilted -45° relative to Figure 6b Each set of joints is configured to allow the active bending segment 200-II to articulate in a direction or plane perpendicular to the corresponding articulation plane.

[0098] As mentioned above Figure 5a to Figure 5e As described above, the guide elements 304 on the tube elements 202A, 202B are offset by 45° in the circumferential direction from the adjacent joint sockets 204A and joint heads 204B on the respective tube elements 202A / B (and therefore from the adjacent joints). Thus, when the control line is arranged in the guide elements 304, the control line extends in two line planes that are tilted or rotated 45° relative to each of the articulation planes. For example, the first pair of guide elements 304 on each element 202A, 202B is arranged in a direction opposite to the first pair of guide elements 304 on the tube elements 202A, 202B. Figure 6a In a first line plane parallel to the viewing direction, the second pair of guide elements on each element 202A, 202B is arranged perpendicular to Figure 6a The viewing direction (and therefore Figure 6b When one or two control lines in a given line plane are actuated (e.g., by pulling or releasing the corresponding control line to adjust the longitudinal tension generated by the corresponding control line via the attachment point on the outermost distal element 402B), the first set of engagement members and the second set of engagement members are actuated simultaneously, thereby causing the active bending segment 200-II to bend in the corresponding line plane. Figure 4a , 4b Compared to the arrangement in , at a given bending radius of the active bending section 200-II, the articulation angle of each actuating joint can, for example, be approximately half.

[0099] The examples of the present disclosure disclosed herein constitute only specific examples for illustrative purposes. The present invention can be implemented in various ways and can be modified in many ways without changing the basic properties. Therefore, the present invention is limited only by the following claims.

Claims

1. A tube (200) for an endoscope (100), characterized in that: The tube (200) comprises a plurality of elements (202, 402A, 402B) arranged along a centerline (201) of the tube (200) and pivotably connected to each other by a plurality of joints (204, 404), the joints (202, 404) allowing the tube (200) to bend relative to a default configuration of the tube (200), wherein each of the joints (204, 404) comprises: an engagement member head (204B) on a corresponding first element (202B, 402B) of the plurality of elements (202, 402A, 402B); and a joint member socket (204A) on a corresponding second element (202A, 402A) of the plurality of elements (202, 402A, 402B), the joint member socket (204A) being configured to receive the joint member head (204B), wherein the shapes of the joint socket (204A) and the joint head (204B) are such that when the first element (202B, 402B) pivots relative to the second element (202A, 402A) from a default articulation angle of the joint (204) associated with the default configuration to a target articulation angle: A first contact surface (206B) on the joint head (204B) engages with a second contact surface (206A) on the joint socket (204A) so that the joint head (204B) is pushed outward from the joint socket (204A) so that a displacement (D) of the joint head (204B) along the center line (201) of the tube (200) relative to its position at the default articulation angle is greater than zero for any target articulation angle.

2. The tube (200) according to claim 1, characterized in that The first contact surface (206B) includes a protruding portion (208B) protruding from an inscribed circle (210B) of the first contact surface (206B), and the second contact surface (206A) includes a recessed portion (208A) recessed from an inscribed circle (210A) of the second contact surface (206A); When the first element (202B, 402B) is at the default hinge angle, the protrusion (208B) of the first contact surface (206B) faces the recess (208A) of the second contact surface (206A); and When the first element (202B, 402B) pivots from the default articulation angle to the target articulation angle, the protrusion (208B) engages with the second contact surface (206A), so that the joint head (204B) is pushed outward from the joint socket (204A).

3. The tube (200) according to claim 1 or 2, characterized in that The first contact surface (206B) includes a first straight portion (206B-I) and a second straight portion (206B-II) extending at a certain angle to the first straight portion (206B-I), and the first straight portion (206B-I) and the second straight portion (206B-II) are arranged so that when the first element (202B, 402B) is at the default articulation angle, the first straight portion (206B-I) and the second straight portion (206B-II) each contact the corresponding straight portion (206A-I, 206A-II) of the second contact surface (206A).

4. The tube (200) according to claim 2 or 3, characterized in that The first straight portion (206B-I) and the second straight portion (206B-II) of the first contact surface (206B) are tangent to the inscribed circle (210B) of the first contact surface (206B), and the protruding portion (208B) of the first contact surface (206B) is arranged between the first straight portion (206B-I) and the second straight portion (206B-II).

5. The tube (200) according to any one of the preceding claims, characterized in that The shapes of the joint socket (204A) and the joint head (204B) are such that when the first element (202B, 402B) is pivoted from the default articulation angle to a target articulation angle that differs from the default articulation angle by not less than 10°, preferably not less than 20°, the displacement of the joint head (204B) along the center line (201) of the tube (200) relative to its position at the default articulation angle increases monotonically.

6. A tube (200) according to any one of the preceding claims, characterised in that The shapes of the joint socket (204A) and the joint head (204B) are such that when the first element (202B, 402B) is at the default articulation angle, the tip of the joint head (204B) is separated from the joint socket (204A) by a gap (214).

7. A tube (200) according to any one of the preceding claims, characterised in that The fastener socket (204A) is configured such that the fastener head (204B) can be removed from the fastener socket (204A) along the centerline (201) of the tube (200).

8. The tube (200) according to any one of the preceding claims, characterized in that The joint socket (204A) and / or the joint head (204B) include a transverse mechanical stop (500), which is configured to limit the movement of the joint head (204B) relative to the joint socket (204A) in a direction parallel to the hinge axis of the joint (204, 404).

9. The tube (200) according to any one of the preceding claims, characterized in that The maximum articulation angle of one or more joints (204, 404) of the plurality of joints (204, 404) is different from the maximum articulation angle of other joints (204, 404) of the plurality of joints (204, 404).

10. The tube (200) according to claim 9, characterized in that The elements (202, 402A, 402B) are arranged in a chain, and the outermost joints (404) at one or both ends of the chain have a smaller maximum articulation angle than other joints (204) in the chain.

11. The tube (200) according to claim 10, characterized in that The maximum articulation angle of the outermost joint (404) at one or both ends of the chain is between 10% and 70% of the maximum articulation angle of the other joints (204) in the chain.

12. The tube (200) according to claim 10 or 11, characterized in that For each of the joints (204, 404), the first element (202B, 402B) includes a first angled end surface (302B), the second element (202A, 402A) includes a second angled end surface (302A) facing the first angled end surface (302B), the first angled end surface (302B) and the second angled end surface (302A) being configured to contact each other when the joint (204, 404) reaches its maximum articulation angle to prevent the joint (204, 404) from further articulation; and When the corresponding joints (204, 404) are at the default articulation angle, the angle between the first angled end face (302B) and the second angled end face (302A) associated with the outermost joints (404) at one or both ends of the chain is smaller than the angle between the first angled end face (302B) and the second angled end face (302A) associated with other joints (204) in the chain.

13. The tube (200) according to any one of the preceding claims, characterized in that Some or all of the elements (202, 402A, 402B) include a guide element (304, 304A, 304B) configured to guide a control line for actuating the plurality of engagement members (204, 404).

14. The tube (200) according to claim 13, characterized in that The guide elements (304, 304A, 304B) are arranged on the periphery of the corresponding elements (202, 402A, 402B).

15. The tube (200) according to claim 13 or 14, characterized in that The guide elements (304A, 304B) are configured to guide the control line so that the control line is arranged adjacent to an inner side surface or an outer side surface of a joint head (206B) on the corresponding element (202B) or an adjacent element (202B).

16. The tube (200) according to any one of claims 13 to 15, characterized in that At least some of the elements (202A, 202B) each: The first and second pairs of engagement members (204) are pivotally connected to the respective first adjacent elements (202B, 202A) by respective first pairs of engagement members (204) arranged on opposite sides of the tube (200), and are pivotally connected to the respective second adjacent elements (202B, 202A) by respective second pairs of engagement members (204) arranged on opposite sides of the tube, the first and second pairs of engagement members (204) being displaced 75° to 105° relative to each other along the circumferential direction (φ) of the tube (200); and It comprises four guide elements (304) arranged along the circumference of the corresponding elements (202A, 202B), each of the four guide elements (304) being staggered with the adjacent engagement member (204) by 35° to 55° along the circumferential direction (φ) of the tube (200).

17. The tube (200) according to any one of the preceding claims, characterized in that Each of the elements (202, 402A, 402B) extends around a respective passage opening (300), and the diameter of the passage opening (300) varies along the circumference of the respective element (202, 402A, 402B) by less than 25%, preferably less than 15%.

18. The tube (200, 700) according to any one of the preceding claims, characterized in that The tube (200) is an insertion tube or a hypotube for the endoscope (100).

Images