Articulated surgical instrument for robotic or microsurgical procedures, method of manufacture, and method of assembly

Abstract

The invention relates to a surgical instrument (1) comprising an articulated end (10) comprising: a first support link (11); a second link (12) articulated with respect to the support link about an axis of rotation (Y-Y); a transmission cable (15, 16) fixed to the second link (12); wherein the first support link comprises: at least one first convex regular surface (17, 19) having straight generatrix lines all parallel to one another; at least one second convex regular surface (18) having straight generatrix lines all parallel to one another; the transmission cable (15, 16) is configured to transmit a signal when the second link (12; 13) slides on said at least one first surface (17, 19) and said second surface (18) of the first support link (11) when rotating relative to the support link; the straight generatrix of the at least one first convex regular surface (17, 19) is orthogonal to the straight generatrix of the second convex regular surface (18).

Description

Technical Field

[0001] The present invention relates to a surgical instrument.

[0002] In particular, a surgical instrument according to the present invention comprises an articulated end portion.

[0003] The surgical instrument according to the invention is particularly suitable for use as a component of surgical and / or microsurgical teleoperation.

[0004] The present invention also relates to a method of manufacturing at least a portion of an articulating end portion of a surgical instrument.

[0005] Furthermore, the invention relates to a method of assembling a surgical instrument. Background Art

[0006] Robotic surgical equipment is generally known in the art and generally includes a central robotic tower (or cart) and one or more robotic arms extending from the central robotic tower. Each arm includes a motorized positioning system (or manipulator) for distally moving surgical instruments attachable thereto in order to perform a surgical procedure on a patient. The patient typically lies on a surgical table located in an operating room, where sterility is ensured to avoid bacterial contamination due to non-sterile parts of the robotic equipment.

[0007] Miniaturization of surgical instruments, and especially their articulated ends ("end effectors") for use in robotic surgery, is particularly desirable because it opens up advantageous scenarios of minimal invasiveness for the patient undergoing surgery as well as millimeter and submillimeter tissue dissection capabilities.

[0008] For example, US-10582975, WO-2017-064303 and WO-2018-18972 of the same applicant disclose various embodiments of surgical instruments suitable for robotic surgery and microsurgery, in which, in order to miniaturize the joint, the tendons slide and are guided in their sliding motion without the need to provide holes or concave guide channels. In contrast, the actuating tendons are supported and held in place by suitable convex sliding surfaces, which are regular surfaces with generatrixes all parallel to each other, each regular sliding surface being parallel to a given axis.

[0009] Furthermore, documents WO-2017-064305, EP-3362218 and EP-3597340 of the same applicant disclose some methods for manufacturing surgical instruments of this type, and in particular the connecting rods of the articulated ends of surgical instruments, by wire electroerosion (WEDM) using a cutting wire to make continuous cuts in orthogonal planes. Such manufacturing techniques require the manufacture of openings in the pin joints, i.e., it requires the creation of holes suitable for receiving the pins, which holes must be provided with channels for the passage of the cutting wires, wherein such channels have a smaller size than the diameter of the pins to be received in the holes.

[0010] WO-2018-189722 of the same applicant discloses a surgical instrument in which the tendons for actuating the opening / closing degree of freedom of an articulated end effector, in addition to sliding on the convex regular sliding surface of the end effector link, are also wound around the convex regular sliding surface, describing an arcuate path under a particularly high winding angle. In fact, by virtue of the low sliding friction of the tendons, they are able to maintain contact with the convex regular surface of the link over a relatively long and arcuate longitudinal section.

[0011] In addition, US-2021-0106393 of the same applicant discloses some embodiments of tendons composed of interwoven polymer fibers. The use of polymer tendons allows for reduced sliding friction relative to the use of metal tendons, and at the same time the appropriate size of the tendons allows for a coiled longitudinal path to be traveled in a miniaturized articulated end effector.

[0012] Surgical instruments are also known which are provided with an articulated cutting end, actuated by means of an actuation cable wound around at least two pulleys, wherein the blade holder comprises a distal pulley of increased diameter relative to the proximal pulley of the same articulated end, in an attempt to increase the cutting force by increasing the radius of the distal actuation pulley. Generally, it is desirable to keep the diameter of the blade actuation pulley within the overall dimensions of the articulated end positioning rod or shaft at all costs, so as not to increase the longitudinal dimensions of the surgical instrument.

[0013] Even if the surgical instrument is not intended to perform a cutting action, there is a need to maximize the closing torque, and therefore the closing force, between the tips (jaws) of the articulated instrument, while minimizing the stress on the actuation cable. For example, a surgical instrument may need to exert a firm and durable gripping action. This need is particularly evident in miniaturized instruments, whose actuation cable action rods are very small. This need is particularly evident in miniaturized instruments using small gauge cables or polymer cables, which have limited breaking force and / or low stiffness and / or significant plasticity when subjected to load.

[0014] In order to guide the actuation cable towards the distal actuation pulley with a relatively large diameter, WO-2017-098279, for example, uses intermediate guide pulleys with inclined axes, which are driven to rotate by the cables themselves when the pulleys are actuated.

[0015] A different known solution shown in US-9186221 shows an actuation cable deflected from an inner distal wall of a support link (a "clevis" or even a "fork"); in other words, this document shows an example in which the support link houses the actuation cable in a guide channel in which the outer wall of the channel, facing the longitudinal centerline of the surgical instrument, acts as a diverter of the cable path, allowing the cable to be wound on a distal actuation pulley.

[0016] Such known solutions are not suitable for miniaturization because they require many parts to assemble and in particular more idle return pulleys to keep the actuating cable in place, or they have difficult to perform undercut machining or guide channels, which forces the actuating cable to be in place against the wall of the cavity, thus shortening its service life and creating high friction at the point providing relative movement between the actuating cable and the pulley or other articulated end part.

[0017] A different type of surgical instrument consists of an instrument for electrosurgery, which includes one or more power cables for electrically actuating the end portion, i.e. the free end, of an articulated surgical instrument. In such known instruments for electrosurgery, the electrical energy is usually conducted by providing an electrical cable connected to the active distal portion. The aforementioned electrical cables are usually inflexible and therefore cannot follow the winding path of the articulated end actuation cable, which usually results in the formation of bulky bends and loops by the same electrical cable when the articulated end is articulated (i.e. moved). Such effects achieved by the power cable are obviously particularly pronounced, but are undesirable in the case of miniaturized surgical instruments, since the formation of such "curled" or "flying" sections of the lateral cantilever towards the outside of the power cable would hinder the design efforts aimed at obtaining a minimum volume of the components and members of the miniaturized articulated end. In order to avoid forming such bends and loops that extend far beyond the volume of the articulated end and to avoid the undesirable risk of interference with the patient's anatomy and / or with another surgical instrument and / or with other elements of the surgical site, articulation of the electrosurgical instrument is used as little as possible in an attempt to always keep the articulated instrument in a straight, extended position.

[0018] Therefore, there is a strong need to provide a solution that can increase the closing torque of a miniaturized articulated surgical instrument without increasing the size of the instrument itself and without reducing the flexibility of the articulation.

[0019] Therefore, there is a strong need to provide a solution that can minimize the stress on the actuation cables of miniaturized articulated surgical instruments that use small gauge cables or polymer cables that have limited breaking force and / or low stiffness and / or significant plasticity when subjected to load.

[0020] Furthermore, there is a need to provide a durable and reliable cable for an articulating surgical instrument, even when operating conditions require sliding on the articulating end. Summary of the invention

[0021] The object of the present invention is to eliminate the disadvantages expressed with reference to the prior art.

[0022] Another object of the present invention is to provide an articulated surgical instrument suitable for miniaturization.

[0023] This object and other objects are achieved by a surgical instrument according to claim 1 as well as a production method according to claim 16 and an assembly method according to claim 17 .

[0024] Advantageous embodiments are the subject matter of the dependent claims.

[0025] According to one aspect of the invention, a surgical instrument includes an articulating end portion including: a support structure; a second link articulated relative to the support structure about a rotational axis; and a transmission cable secured to the second link.

[0026] The support structure may include: at least one first sliding surface, which is a convex regular surface with straight generatrixes all parallel to each other; and a second sliding surface, which is a convex regular surface with straight generatrixes all parallel to each other.

[0027] The support structure may comprise a support link, and the at least one first surface and the second surface may each be made as a single component with the support link.

[0028] The transmission cable is configured to slide on the at least one first surface and the second surface when the second link rotates relative to the support structure.

[0029] At least one straight generatrix of the first convex regular sliding surface is orthogonal to the generatrix of the second convex regular sliding surface.

[0030] The second convex ruled surface may be parallel to an axis of relative rotation between the second link and the support structure.

[0031] At least one sliding surface between the at least one first surface and the second surface may face a definable longitudinal centerline of the hinged end.

[0032] The transmission cable may be wound around the winding pulley of the second link.

[0033] A transmission cable may be secured to the take-up pulley.

[0034] The transmission cable may comprise an operative distal end for entraining the second link, the distal end being received in a termination site obtained in the disc-shaped volume of the winding pulley.

[0035] The winding pulley may comprise a winding surface for the transmission cable, the winding surface being a convex regular surface having straight generatrixes which are all parallel to each other and to the straight generatrix of the second sliding surface.

[0036] The winding pulley of the second link may protrude laterally relative to the second convex regular sliding surface.

[0037] The radius of the winding pulley may be greater than or equal to the distance between the first convex ruled surface or the second convex ruled surface and the central axis of the surgical instrument.

[0038] Preferably, the sliding contact angle between the transmission cable and at least one of the at least one first surface and the second surface does not change for any operational configuration of the articulated end.

[0039] The at least one first sliding surface and the second sliding surface are preferably longitudinally spaced apart from each other.

[0040] By means of the proposed solution, a miniaturized surgical instrument is provided, in which the closing torque is maximal.

[0041] By means of the proposed solution, a miniaturized surgical instrument is provided, wherein the load on the actuation cable is optimized.

[0042] By means of the proposed solution, a miniaturized surgical instrument is provided, which is equipped with a cable that slides on the surface of the articulated end of the instrument when in operating conditions, which makes it possible to keep the friction of the cable sliding on the surface to a minimum and to keep the cable within the volume of the articulated end.

[0043] According to one aspect of the present invention, a method for manufacturing at least the first support link of an articulated end of a surgical instrument by wire electroerosion is provided, wherein the first support link includes a convex regular sliding surface having straight generatrixes orthogonal to each other, and the method includes the following steps: (i) providing a wire electroerosion machine with a cutting wire; (ii) mounting at least one workpiece to the wire electroerosion machine; (iii) performing a first through-cut on at least one workpiece with the cutting wire of the wire electroerosion machine to form the at least one first convex regular sliding surface; (iv) rotating at least one workpiece 90° relative to the cutting wire; and (v) performing a second through-cut on the same at least one workpiece with the cutting wire of the wire electroerosion machine to form a second convex regular sliding surface.

[0044] The first support link may be simultaneously or subsequently formed by wire electroerosion.

[0045] According to one aspect of the present invention, there is provided an assembly method for a surgical instrument, comprising the following steps: (i) inserting a hinge pin into the through holes of a first support link and a second link, and preferably also into the through hole of a third link; (ii) fixing the operative distal end of a transmission cable having a traction action in a termination seat provided in the body of a winding pulley of the second link; and (iii) winding a distal portion of the operative distal end adjacent to the transmission cable on the surface of the winding pulley.

[0046] The step of fixing the operative distal end of the transmission cable may also include: forming an axially aligned structure between the termination seat of the winding pulley of the second link and the assembly window of the fork-shaped member of the first support link, and axially inserting the operative distal end of the transmission cable into the assembly window of the fork-shaped member of the support link, and inserting it into the termination seat of the winding pulley of the second link in axial alignment therewith.

[0047] With this assembly method, a simple solution is provided while providing a sturdy assembly. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Further features and advantages of the surgical instrument will become apparent from the following description of preferred embodiments, which are given by way of non-limiting illustration, with reference to the accompanying drawings. It should be noted that references to "one" embodiment mentioned in the present disclosure do not necessarily refer to the same embodiment, and should be understood to mean at least one. In addition, for the purpose of simplicity and reducing the total number of drawings, a certain drawing may be used to illustrate features of more than one embodiment, and not all elements of the drawing may be necessary for a certain embodiment.

[0049] Figure 1 is an isometric view of a robotic teleoperation assembly according to one embodiment.

[0050] Figure 2 is an isometric view of a surgical instrument according to one embodiment.

[0051] Figure 3 is an isometric view of an articulating end of a surgical instrument according to one embodiment.

[0052] Figure 4 is an isometric view of a portion of a surgical instrument according to one embodiment.

[0053] Figure 5 is a plan view schematically showing details of an articulated end according to one embodiment.

[0054] Figure 6 is an axonometric view of an articulated end portion including two links according to one embodiment.

[0055] Figure 7 is an axonometric view of a support link according to one embodiment.

[0056] Fig. 8A is based on Figure 7 The viewpoint indicated by arrow VIII Figure 7 Plan view of the support link in FIG.

[0057] Figure 8B is based on Fig. 8A The viewpoint indicated by arrow B Figure 7 Plan view of the support link in FIG.

[0058] Fig. 9 is an axonometric view of an articulated end according to one embodiment.

[0059] Fig.10 is a plan view of an articulated end according to one embodiment.

[0060] Fig.11 is an isometric view of a portion of a surgical instrument including an articulating end according to one embodiment.

[0061] Fig.12 yes Fig.11 An axonometric view of a portion of a surgical instrument in which some parts are omitted for clarity.

[0062] Fig.13 yes Fig.11 A plan view of a surgical instrument in FIG. 1 , with some details of the invisible connecting rods of the articulated end schematically shown in dotted lines.

[0063] Fig.14 is a plan view of a portion of an articulated end portion according to one embodiment.

[0064] Fig.15is an axonometric view of a portion of an articulated end portion according to one embodiment.

[0065] Fig.16 is a plan view of a portion of an articulated end portion according to one embodiment.

[0066] Fig.17 yes Fig.16 A plan view of a portion of the articulated end in a possible operating configuration.

[0067] Fig.18A is a plan view of a support link of an articulated end according to one embodiment.

[0068] Fig.18B is based on Fig.18A The arrow B in the figure indicates the viewpoint Fig.18A Plan view of the support link in FIG.

[0069] Fig. 18C yes Fig.18A Axonometric view of the support link in Figure 1.

[0070] Fig.19A is a schematic plan view of a portion of an articulated end according to one embodiment, with some parts transparent for clarity.

[0071] Fig.19B yes Fig.19A Schematic plan view of a portion of the hinged end of .

[0072] Fig. 20 is a plan view of an articulated end according to one embodiment.

[0073] Fig.21 is a plan view of a second link of an articulated end showing two transmission cables according to one embodiment.

[0074] Fig.22A and Fig. 22B Some possible steps of a method of manufacturing by wire electroerosion according to one embodiment are shown. DETAILED DESCRIPTION

[0075] Throughout this specification, references to "one embodiment" mean that the specific features, structures, or functions described in connection with that embodiment are included in at least one embodiment of the present invention. Therefore, the phrase "in one embodiment" in various parts of this specification does not necessarily refer to the same embodiment. In addition, in one or more embodiments, specific features, structures, or functions, such as those shown in different figures, can be combined in any suitable manner.

[0076] According to a general embodiment, a surgical instrument 1 is provided, comprising an articulating end 10 or an articulated end effector 10. The articulating end 10 may comprise at least one free end and / or at least one opening / closing articulation G (grasping and / or cutting).

[0077] The surgical instrument 1 is particularly suitable for being mounted on a robotic assembly 2 for medical or surgical or microsurgical teleoperation.

[0078] The articulated end 10 may include a plurality of links 11, 12, 13, 20 that are articulated to each other by providing one or more rotational joints. Preferably, the articulated end 10 includes a plurality of degrees of freedom that are moved by providing a plurality of transmission cables 15 (or actuation tendons 15) with a traction action that extend from the proximal transmission interface portion 23 along the longitudinal extension of the positioning rod or shaft 21 of the surgical instrument 1 to reach the articulated end 10.

[0079] The articulated end 10 of the surgical instrument 1 comprises a support structure 31, which comprises at least one first support link 11 and a second link 12, which is articulated relative to the first link 11 of the support structure 31. Therefore, the first support link 11 and the second link 12 are articulated so that they can rotate relative to each other around a rotation axis YY. For example, the rotation axis YY is the deflection axis of the articulated end 10. For example, the first support link 11 and the second link 12 form a rotating pin joint.

[0080] The second link 12 may include a free terminal end 33 forming a terminal end of the surgical instrument 1 .

[0081] The articulated end 10 may further include a third link 13, which is articulated relative to the first link 11 of the support structure 31, and the third link forms an opening / closing joint motion G with the second link 12. In this case, the third link 13 and the second link 12 are articulated relative to each other around a rotation axis (which may coincide with the above-mentioned deflection rotation axis YY). The third link 13 may also include a terminal free end 39, which, for example, forms the terminal end of the surgical instrument 1 together with the terminal free end 33 of the second link 12, wherein the terminal ends 33 and 39 of the corresponding links 12, 13 can move relative to each other during the opening / closing G, for example by rotating relative to each other around the deflection rotation axis YY. Other configurations are also possible, for example, the third link 13 can be articulated to the second link 12 around a rotation axis located distal to the deflection rotation axis YY.

[0082] The supporting link 11 preferably comprises two forks 34 extending distally to form an assembly seat for the articulation pin 35 and the winding pulley 14 of at least the second link.

[0083] The winding pulley 14 preferably defines an axial through hole 36 for receiving the hinge pin 35. The fork 34 of the support link 11 may also include a corresponding through hole 40 for receiving the hinge pin 35.

[0084] According to one embodiment, the hinge pin 35 is rotatably integrated with the winding pulley 14 of the second link 12. For example, the hinge pin 35 is keyed in a through hole of the winding pulley 14.

[0085] The arrangement of the articulation pin rotatably integrated with the winding pulley allows a reduction in the cutting reaction forces on the articulation pin 35 itself, when provided in a configuration in which the axes of rotation of the deflection degree of freedom of the articulation end and the opening / closing (gripping) degree of freedom (and therefore preferably also the articulation pin) coincide, This facilitates the movement of the deflection joint when the articulation end 10 of the surgical instrument is in the gripping or squeezing or cutting state.

[0086] In fact, when in operation and in the squeezing or gripping or cutting state, the reaction to the gripping force on the respective link 12, 13 generates two equal and opposite cutting forces on the articulation pin 35, which in turn generates a rolling friction torque between the articulation pin 35 and the respective winding pulleys of the links 12, 13, the articulation pin and the links tending to "bind", i.e., to make the three elements (pin 35, link 12 and link 13) rotatably integral with the support link 11. For this reason, if the articulation pin 35 is rotatably integral with the support link 11 (e.g. keyed to the fork 34), the elongated bodies of the links 12 and 13 will essentially form a clamp for the articulation pin. In other respects, by making the articulation pin 35 rotatably integral with the winding pulley 14 of the second link 12, the above-mentioned effect can be utilized in an advantageous manner and in particular is intended to make the links 12 and 13 rotatably integral only during gripping, cutting or squeezing actions, while maintaining free rotation between the pin and the fork 34 supporting the link 11, since deformation of the pin and the fork is minimal in the area of ​​mutual connection.

[0087] Preferably, the axial through hole 36 of the winding pulley 14 of the second link 12 includes at least one elastically deformable wall 37 (for example, formed by a cantilever protrusion 37) for elastically clamping the hinge pin 35, so that the second link 12 can be rotatably integrated with the hinge pin 35, for example during the movement of the freedom of opening / closing G and during the assembly of the links 11, 12, 13 of the hinged end 10 and during the assembly of, for example, a deflection rotary joint.

[0088] The support structure 31 including the first support link 11 may be an articulated structure, i.e., having at least one internal degree of freedom formed by an articulated joint between two or more links, and including another link (e.g., the proximal link 20) ​​articulated to the first support link 11. For example, the support structure 31 may include therein a pitch joint about a pitch rotation axis PP between the proximal link 20 and the support link 11, and at the same time may form a yaw joint about a yaw rotation axis YY with the second link 12 and with the third link 13, the yaw rotation axis being orthogonal to the pitch rotation axis PP. The proximal link 20 may be fixed to a shaft or rod 21.

[0089] It should be clear that according to a preferred embodiment, the terms pitch and yaw are used arbitrarily for the sake of a clearer explanation. According to another embodiment, for example, the pitch rotation axis PP and the yaw rotation axis YY form an angle other than 90° therebetween.

[0090] The articulated end 10 further comprises transmission cables 15 , 16 fixed to the second link 12 .

[0091] According to a preferred embodiment, the transmission cable is a transmission cable with traction action 15, which is configured to apply a traction action to the second link 12 so that it rotates relative to the first support link 11. A transmission cable with traction action can be provided, which is configured to apply a traction action to the third link 13 so that it rotates relative to the first support link 11 and preferably also relative to the second link 12.

[0092] Preferably, the supporting link 11, the second link 12 and the third link 13 are each moved by a pair of opposing actuating cables 151, 152 which can be received in corresponding terminal seats 26 provided in the body of the winding pulley 14 of the second link 12, as for example in Fig.21 . Other configurations are also possible. For example, the termination seat 26 can be made on the outer radial surface of the winding pulley 14, for example by including a radial protrusion extending from the pulley to form an undercut seat for the transmission cable 15 of the traction action TR. The transmission cable 15 with the traction action TR can therefore apply the traction action TR to the second link 12, so that the winding pulley 14 and thus the terminal free end 33 in the opening / closing G (if provided) are driven to rotate by means of the undercut abutment 42.

[0093] The third link 13 may also include a winding pulley as described with reference to the winding pulley 14 of the second link 12 .

[0094] According to a preferred embodiment, the winding pulley 14 comprises a substantially disc-shaped body defining at least one terminal seat 26 for an operative distal end 41 of the transmission cable 15, which operative distal end can be, for example, an enlarged operative distal end 41 formed by a node consisting of the same transmission cable 15, so as to increase the contact surface with the undercut drag wall 42 formed by the body of the winding pulley 14 at the inlet 43 of the terminal seat 26. The mouth 43 or inlet 43 of the terminal seat 26 can be radially outward, as for example in Fig.21 , i.e. it can extend from the disk-shaped body of the winding pulley 14 in a radial direction RR relative to the radius of the disk. The mouth 43 or inlet 43 of the terminal seat 26 can also be axially facing, i.e. it can also open in a direction parallel to the rotation axis YY, forming an axial through seat.

[0095] The undercut wall 42 (on which the operative distal end 41 of the transmission cable 15 abuts to drive the winding pulley 14 of the second link 12 in rotation) may be formed by a cantilevered circumferential protrusion 44 (i.e., extending circumferentially to form a free end) of the disk-shaped body of the winding pulley 14, which delimits a radially open mouth 43 of the termination seat 26. Preferably, therefore, the contact surface 45 of the cantilevered circumferential protrusion 44 in contact with the section of the transmission cable 15 adjacent to its distal end 41 may be a convex curved surface and has no circumferentially and / or radially facing edges relative to the disk-shaped body of the winding pulley 14 of the second link 12. For example, such a contact surface 45 of the winding pulley 14 is a convex regular surface formed by generatrixes that are all parallel to each other and to the axis of rotation YY of the winding pulley 14 of the second link 12.

[0096] Alternatively or additionally, a power transmission cable 16 configured to transmit power to the second link 12 may be provided. In this case, the surgical instrument 1 may be an electrosurgical or micro-electrosurgical instrument. A power transmission cable 16 configured to transmit power to the third link 13 may be provided. In this case, the second link 12 may be a link adapted to perform a gripping action and comprising a gripping surface 32.

[0097] According to one embodiment, the supporting structure 31 of the articulated end 10 comprises at least one first convex regular surface 17, 19 defined by straight generatrixes π all parallel to one another, and at least one second convex regular surface 18 defined by straight generatrixes υ all parallel to one another.

[0098] According to a preferred embodiment, the first supporting link 11 of the hinged end 10 includes at least one first convex regular surface 17, 19, which is defined by straight generatrixes π that are all parallel to each other, and at least one second convex regular surface 18, which is defined by straight generatrixes υ that are all parallel to each other.

[0099] Advantageously, the straight generatrix π of at least one first convex regular surface 17, 19 is orthogonal to the straight generatrix υ of the second convex regular surface 18. According to one embodiment, at least one first regular convex surface 17, 19 has straight generatrix π all parallel to the pitch rotation axis PP, and the second regular convex surface 18 has straight generatrix υ all parallel to the yaw rotation axis YY. Therefore, the convex regular surfaces 17, 18, 19 are curved surfaces and are parallel to the corresponding generatrix π, υ directions at the same time.

[0100] A further advantage is that when the second link 12 rotates relative to the first support link 11 , the transmission cable 15 or 16 is configured to slide on the at least one first surface 17 , 19 and the second surface 18 of the first support link 11 .

[0101] The sliding direction of the transmission cable 15 or 16 on the respective convex regular surface 17, 18, 19 is thus always orthogonal to the generatrix of the convex regular surface on which the transmission cable slides. Therefore, the curvature of the convex regular surface 17, 18, 19 faces the transmission cable 15, 16 sliding on said convex regular surface and in a transverse direction relative to the transmission cable 15, and the convex regular surface 17, 18, 19 is substantially flat. Therefore, the transmission cable slides orthogonally to the generatrix of the respective convex regular surface.

[0102] The proximal link 20 may include a third convex ruled surface 30 having straight generatrixes all parallel to each other for sliding of the proximal sections of the transmission cables 15 , 16 .

[0103] Preferably, the straight generatrixes of the third convex ruled surface 30 are all parallel to the generatrix of at least one first ruled surface 17 , 19 , for example parallel to the pitch rotation axis PP.

[0104] The straight generatrix of the third convex ruled surface 30 may all be parallel to the generatrix of the second convex ruled surface 18 , for example parallel to the deflection rotation axis YY of the articulated end portion 10 .

[0105] At least one first convex regular sliding surface 17, 19 and / or second convex regular sliding surface 18 may be provided on the proximal link 20 instead of being provided on the first support link 11. According to one embodiment, the proximal link 20 may include a third regular surface 30 and a fourth convex regular surface perpendicular to each other. The presence of one or more convex regular sliding surfaces on the proximal link 20 also ensures adhesion of the actuation cable to the link forming the articulated end during movement throughout the range of motion.

[0106] Preferably, the transmission cable 15 or 16 does not slide on the second link 12. According to a preferred embodiment, the second link 12 comprises a winding pulley 14 and the transmission cable 15 with a pulling action is wound around said winding pulley 14. When in operating conditions, the transmission cable 15 with a pulling action is pulled so as to rotate the second link 12 relative to the first supporting link 11 around the rotation axis YY. The pulling of the transmission cable 15 means that the same transmission cable 15 slides on the at least one first convex regular surface 17, 19 having a generatrix parallel to the pitch axis PP and on the second convex regular surface 18 having a generatrix parallel to the yaw axis YY. In other respects, the same transmission cable 15 does not slide on the winding pulley 14 of the second link 11, because the transmission cable 15 is wound and unwound on said pulley 14 instead of sliding. The transmission cable 15 is preferably terminated in a termination seat 26 formed integrally with said winding pulley 14 of the second link 11.

[0107] The winding pulley 14 is preferably made in a single part with the body of the second link 12 and with the terminal end 33 of the second link. Alternatively, the second link 12 is formed by at least two rotatable integral parts assembled together, and the at least two parts of the second link 12 may include the winding pulley 14 and the blade link 25, the winding pulley forming a kind of blade holder link. Alternatively, the second link 12 is formed by at least two parts assembled together that can be moved rotationally relative to each other, and the at least two parts of the second link 12 may include the winding pulley 14 and the blade link 25 that can rotate relative to the winding pulley. The free end 33 of the second link 12 can be made in a single part with the winding pulley 14 or with the blade link 25.

[0108] The assembly of the transmission cable 15 with the pulling action TR can be completed by axially inserting the terminal end 41 of the transmission cable 15 into the terminating seat 26 of the winding pulley 14 of the second link 12. The second link 12 can then be assembled to the first supporting link 11 and / or the third link 13 by inserting the hinge pin 35 into the corresponding through hole of the links 11, 12, 13. In the case where an elastic tab 37 for clamping the hinge pin 35 is provided, the hinge pin 35 can be assembled to the second link 12 first.

[0109] The fork-shaped member 34 of the support link 11 may include an assembly window 48, i.e., a through opening in the direction of the rotation axis YY, which is specifically arranged at the same radial height of the terminal seat 26 of the second link 12 (i.e., along the radius of the pulley 14 of the second link 12) to define at least one relative arrangement between the first support link 11 and the second link 12, wherein the assembly window 48 of the link 11 is aligned with the terminal seat 26 in the second link 12, so that when the second link 12 is assembled to the first support link 11, assembly is allowed by axially inserting the enlarged distal end 41 of the transmission cable 15 with the traction action TR into the assembly window 48 of the first support link 11 and the terminal seat 26 of the winding pulley 14 of the second link 12.

[0110] The convex regular surfaces 17, 18, 19, 30, 45 can be made by a manufacturing process performed by wire electroerosion on two cutting planes (for example, two orthogonal cutting planes), so that the cutting wire 51 of the wire electroerosion machine 50 is parallel to the pitch rotation axis PP or the yaw rotation axis YY in each cutting configuration.

[0111] For example, the through hole 26 of the second link 12 for receiving the hinge pin 35 may communicate with the through hole forming the terminal seat 26 by a wire electro-erosion manufacturing process in which cutting the wire describes a continuous cutting path that also forms the through hole.

[0112] According to a preferred embodiment, the supporting link 11 is made as a single part by wire electro-erosion, and in particular by making two cuts on corresponding cutting planes orthogonal to each other. Thus, it is possible to create convex regular sliding surfaces on a single link, which are orthogonal to each other and are arranged along the path of the transmission cable at the same time.

[0113] According to a preferred embodiment, the winding pulley 14 projects laterally relative to the second convex regular surface 18 of the first supporting link 11 .

[0114] Preferably, the winding pulley 14 of the second link 12 has a lateral extension defining the maximum lateral dimension of the articulated end 10 .

[0115] The winding pulley 14 of the second link 12 may have a larger diameter than the lateral extension of the positioning rod or shaft 21 of the surgical instrument 1 , although preferably the diameter of the winding pulley 14 is equal to or smaller than the lateral extension of the positioning rod or shaft 21 .

[0116] According to one embodiment, as in Fig.10, the winding pulley 14 of the second link 12 has a radius R14 that is greater than the transverse distance P1 between the path described by the transmission cables 15, 16 on the at least one first surface 17, 19 and the at least one second surface 18 and the longitudinal centerline 22 of the articulated end 10. In other words, as in e.g. Fig.10 As shown in FIG. 1 , the diameter of the winding pulley 14 is greater than a transverse distance P2 measured along the pitch axis PP (e.g., measured between a path described by the transmission cable on the respective at least one first convex ruled surface 17, 19 and the respective second ruled surface 18 and a path described by the opposing transmission cable on the respective at least one first convex ruled surface and the respective second ruled surface). For example, if the transmission cable 15 is a transmission cable with a traction force TR, the winding pulley 14 has a diameter greater than a transverse distance P2 between an outward path 151 and a return path 152 described by the opposing transmission cable and / or described by the same transmission cable configured to act in two opposite, opposing directions.

[0117] According to one embodiment, said pulley radius R14 of the winding pulley 14 is equal to the greatest dimension or thickness of the articulated end portion 10 .

[0118] According to a preferred embodiment, the second link 12 is moved in opposite directions by two transmission cables 15 having a pulling action TR and each transmission cable comprises an enlarged distal end received in a respective terminal seat 26 of the winding pulley 14 of the second link 12 .

[0119] According to a preferred embodiment, the first support link 11 comprises two opposite and facing second convex regular sliding surfaces 18, both facing towards the centre line 22 of the articulated end 10, wherein a transverse distance P2 between said two opposite second surfaces 18, for example measured along the pitch axis PP, is smaller than the diameter of the winding pulley 14 of the second link 12. Thus, the opposite and facing second surfaces 18 each form a diverter, which allows the transmission cable 15 to change its path to be wound around the winding pulley 14. In fact, the path of the transmission cable 15 along the articulated end 10 is preferably straight and substantially parallel to the longitudinal centre line XX of the positioning axis 21, since there is no concave guide hole or concave guide channel for the transmission cables 15, 16 in the articulated end 10, and the transmission cable is diverted away from the centre line 22 by virtue of the provision of said two opposite second convex regular sliding surfaces 18 of the first support link 11.

[0120] The arrangement of the enlarged winding pulley 14, i.e. protruding relative to the second regular surface 18 of the supporting link 11, allows increasing the clamping force of the opening / closing degree of freedom G with the same traction force TR applied to the transmission cable 15. Therefore, this configuration may be advantageous when arranged in combination with a cutting blade 25 arranged on the second link 12 (preferably also on the third link 13).

[0121] According to one embodiment, the first support link 11 comprises at least one second surface cantilever 28 forming a free end 29, wherein the second surface 18 belongs to the second cantilever 28 of the first support link 11. Preferably, the cantilever 28 extends substantially distally (i.e. towards the location where the winding pulley 14 of the second link 12 is arranged), forming at least a free end facing distally. Preferably, the cantilever 28 of the first support link 11 extends in a radial direction RR outside the winding pulley 14 of the second link 12 in the case of assembled articulated end 10. The free end 29 can also face laterally away from the centerline 22, for example in the direction of the pitch axis PP. Preferably, in this case, the second convex regular surface 18 in sliding contact with the transmission cables 15, 16 faces the longitudinal centerline 22 of the surgical instrument to serve as a lateral accommodation element for the cables and, if necessary (i.e. in the case of a protruding winding pulley 14), the second convex regular surface serves as a diverter for the transmission cables 15, 16. The accommodation and diverter functions can be performed both with a substantially straight articulated end 10 and with bending in one or more degrees of freedom determined by the movement of the second link 12 (eg deflection YY and opening / closing G).

[0122] The shape of the second cantilever 28 of the support link 11 may follow the shape of the cross section of the fork 34, for example, if the support link 11 is made as a single component by wire electrodeposition (WEDM) in two cutting planes orthogonal to each other.

[0123] The second support link 11 can be moved by including an actuation rib 46 with a degree of freedom PP, and preferably by providing two opposing actuation ribs 46. Therefore, the body of the support link 11 may include a terminal seat 47 for receiving the operative distal end of at least one actuation rib 46 to move the support link 11 relative to the proximal link 20 around the rotation axis PP. The terminal seat 47 of the first support link 11 is preferably arranged along the centerline 22 of the articulated end 10 and along the centerline of the support link 11, substantially aligned with the position of the through hole 40 along the longitudinal axis XX. The terminal seat 47 may be defined between the distally directed cantilever of the support link 11 and the root of the fork 34 in a direction parallel to the rotation axis PP. For this purpose, the fork 34 of the support link 11 may include a thinner (i.e., narrower) root in the direction of the rotation axis YY and a wider blade operative distal portion. According to one embodiment, the thinner root of the fork 34 is also not aligned with the longitudinal centerline 22 of the support link 11 to form an end seat 47 for the actuating tendons 46 of the support link 11 outside the body of the fork 34, thereby avoiding structural weakening of the fork 34.

[0124] The transmission cables 15 for the actuation tendons 46 of the supporting link 11 and the pulling action of the second link 12 can be made substantially the same. For example, they can both be woven polymer cables.

[0125] The at least one first surface 17, 19 may include a first surface 19 disposed distally relative to the second surface 18. According to a preferred embodiment, the first support link 11 includes a cantilever 27 forming a free end, wherein the at least one first surface 19 belongs to the first cantilever 27. Preferably, the at least one first surface 19 faces the longitudinal centerline 22 of the surgical instrument.

[0126] The at least one first surface 17, 19 may include a first surface 17 disposed proximally relative to the second surface 18. For example, the at least one first surface 17 at least partially surrounds the pitch rotation axis PP and faces away from the pitch rotation axis PP.

[0127] Preferably, at least one of the at least one first surface 17, 19 and the second surface 18 belongs to a ridge or protrusion of the body of the first support link 11. By virtue of the provision of said ridge, the sliding surface is configured cantilevered, thereby limiting the length of the contact section between the transmission cable and the convex regular sliding surface on which the transmission cable slides, thereby reducing the sliding friction.

[0128] Each convex regular sliding surface defines a contact angle α with the transmission cable sliding thereon.

[0129] According to one embodiment, the sliding contact angle α between the transmission cable and at least one of the at least one first surface 17 , 19 and the second surface 18 does not change in any kinematic operating configuration of the articulated end portion 10 .

[0130] The contact angle α between the second surface 18 and the transmission cable 15 may be constant in each operating configuration of the articulated end 10 .

[0131] The contact angle α between the at least one first surface 17, 19 and the transmission cables 15, 16 may vary depending on the operational configuration of the articulated end 10. For example, in some operational configurations it may happen that the transmission cables 15, 16 are not in contact with the contact surface between the at least one first surface 17, 19 and the second surface 18.

[0132] According to one embodiment, the sliding contact angle α between the transmission cables 15, 16 and at least one of the at least one first surface 17, 19 and the second convex surface 18 is less than 90 degrees. Preferably, the contact angle α is less than 45 degrees. According to one embodiment, for each kinematic configuration, the contact angle α is less than 30 degrees.

[0133] According to one embodiment, the sliding contact angle α between the transmission cables 15, 16 and each of the at least one first surface 17, 19 and the second convex surface 18 is less than 90 degrees. Preferably, the contact angle α is less than 45 degrees. According to one embodiment, for each kinematic configuration, the contact angle α is less than 30 degrees.

[0134] The sliding contact angle α between certain convex regular surfaces can vary under operating conditions depending on the kinematic configuration assumed by the linkage chain of the articulated end 10 .

[0135] As for example in Figure 4 As shown in FIG. 1 , when the pitch degree of freedom is activated, the sliding contact angle between the transmission cable 15 and the first regular surface 17 can vary.

[0136] As for example in Fig.17 As shown in FIG. 1 , when the pitch degree of freedom is activated, the sliding contact angle of the transmission cables 15, 16 with the first ruled surface 19 changes. For example, when the articulated end 10 is in an extended configuration aligned with the longitudinal axis XX of the shaft 21, the sliding contact angle with the first ruled surface 19 is minimum, and the sliding contact angle increases with increasing bending of the pitch joint. Therefore, the convex ruled surface 19 can be used as a receiving abutment to keep the transmission cable within the volume of the articulated end 10, thereby avoiding the formation of a loop or cable curl.

[0137] According to a preferred embodiment, the sliding contact angle of the transmission cables 15 , 16 with the second regular surface 18 having a generatrix parallel to the deflection rotation axis YY is constant in any operating configuration of the articulated end 10 .

[0138] As mentioned above, according to one embodiment, the sliding contact angle α between the transmission cable and the at least one first surface 17 , 19 varies depending on the pitch joint configuration, and the sliding contact angle α between the transmission cable and the second surface 18 is constant in any configuration of the articulated end 10 .

[0139] For each sliding contact surface with the same transmission cable, a contact angle α may be defined.

[0140] According to one embodiment, in each configuration of the articulated end 10, the sum of the sliding contact angle α between (i) the transmission cable and at least one first convex surface 17, 19 and (ii) the sliding contact angle α between the same transmission cable and said second convex surface 18 is less than 180°. According to one embodiment, it is also possible that there are two first surfaces 17 and 19 and the total sliding contact angle is less than 180°. The total sliding contact angle of the same transmission cable may be the sum of three or more local contact angles with the corresponding three or more convex regular surfaces of the articulated end 10, and in this case, according to one embodiment, the sum of the total sliding contact angles is less than 180°.

[0141] It may also be desirable to increase the contact angle. According to one embodiment, in each configuration of the articulated end 10, the sum of the sliding contact angle α between (i) the transmission cable and at least one first convex surface 17, 19 and (ii) the sliding contact angle α between the same transmission cable and the second convex surface 18 is greater than or equal to 180°. According to one embodiment, it is also possible that there are two first surfaces 17 and 19 and the total sliding contact angle is greater than or equal to 180°.

[0142] The transmission cable is preferably a cable at least partially made of a polymer material. For example, it is a cable coated with a polymer material. For example, it is a polymer cable made of braided fibers. For example, a polymer cable made of UHMWPE allows low friction compared to cables made of other types of materials.

[0143] According to one embodiment, a first cable section 24 between the at least one first surface 17, 19 and the second surface 18 extends parallel to the longitudinal centerline 22 and / or to the longitudinal axis XX of the surgical instrument 1. Preferably, a second section 38 of the same cable extending distally with respect to the at least one first surface 17, 19 and the second surface 18 extends obliquely with respect to the longitudinal centerline 22 and / or the longitudinal axis XX of the surgical instrument 1, e.g. obliquely away from the centerline 22. The section 24 of the same cable may extend straightly between the third convex regular surface 30 of the proximal link 20 of the support structure 31 and the most distal side between the at least one first surface 17, 19 and the second surface 18.

[0144] According to a preferred embodiment, at least one first surface 17, 19 and the second surface 18 are longitudinally spaced apart from each other. This avoids sliding contact occurring simultaneously on two orthogonal sides of the same cross section of the tendon.

[0145] As mentioned above, according to one embodiment, the first support link 11 comprises at least two longitudinally spaced first surfaces 17, 19. For example, the first surface 19 is disposed on a cantilever 27 extending distally in cantilevered fashion, and the other first surface 17 is disposed on a proximal portion of the support link 11 about the rotation axis PP. The actuating tendons 46 of the support link 11 can be wound around the first proximal surface 17 of the support link 11 without sliding thereon, while the transmission cable 15 with the traction action TR is longitudinally in sliding contact on the same first proximal surface 17 of the support link 11, as for example in Fig. 20 As shown in .

[0146] A longitudinal gap may be provided between the proximal link 20 and the first convex regular surface 17 of the support link 11, in which the opposing transmission cables 151, 152 of the second link 12 having the traction action TR and / or the opposing actuation tendons 46 on the first support link 11 cross each other (each being opposed thereto).

[0147] According to one embodiment, the first surfaces 17, 19 of the support structure 31 are also intended to serve as the third surface 30 of the proximal link 20. Thus, the at least two first surfaces of the support structure 31 may include at least two between the first surfaces 17, 19 of the support link 11 and the third surface 30 of the proximal link 20. The transmission cables 15, 16 may be configured to slide on all at least two first surfaces. At least three convex regular surfaces 17, 18, 19, 30 including the second surface 18 may be provided on the support structure 31, and the transmission cables 15, 16 are configured to slide on all three regular surfaces of the at least three regular surfaces. The at least three convex regular surfaces are preferably spaced longitudinally from each other.

[0148] By longitudinally spacing the convex regular sliding surfaces for the transmission cables from each other, it is possible to prevent a single cross section of the transmission cable from sliding, i.e. from sliding / frictional contact with the connecting rods on both sides. This allows to maximize the service life of the transmission cables 15, 16, since the stresses due to sliding friction are distributed longitudinally. In other words, a certain cross section of the transmission cables 15, 16 contacts only a small portion of the outer surface of the connecting rod of the articulated end 10, thereby avoiding the same cross section from contacting two separate portions.

[0149] A method of manufacturing at least a portion of the articulated end portion 10 according to any one of the above-described embodiments by wire electroerosion will now be described.

[0150] According to a general embodiment, the method for manufacturing at least one supporting link 11 of an articulated end 10 by wire electroerosion comprises:

[0151] - providing a wire electroerosion machine 50 having a cutting wire 51; Figure 22A-22B A schematic diagram of a wire electroerosion machine 50 is shown in FIG.

[0152] - mounting at least one workpiece 111 , 112 , 113 , 120 to the wire electroerosion machine, for example by using a dedicated tool 52 provided with one or more seats to receive one or more respective workpieces 111 , 112 , 113 , 120 ;

[0153] - performing a first through-cut in at least one workpiece using a cutting wire 51 of a wire electroerosion machine;

[0154] - rotating at least one workpiece by 90° relative to the cutting wire, preferably rotating the tool 52 without removing the tool from the machine 50 or the workpiece from the tool;

[0155] A second through-cut is made in at least one of the workpieces 111 , 112 , 113 , 120 using the cutting wire 51 of the wire electroerosion machine.

[0156] By means of such a method, it is possible to manufacture a support link 11 having at least two sliding surfaces 17, 18, 19, which are formed by respective two sweeping movements of the cut wire 51. The cut wire thus serves as a straight generatrix of the convex ruled surfaces 17, 18, 19.

[0157] Preferably, at least one of the first through-cut and the second through-cut forms at least one hole adapted to receive the hinge pin.Thus, the wall of the hole is parallel to at least one sliding surface and at the same time orthogonal to the other sliding surface.

[0158] The method can also be used to manufacture at least one (but also all) of the second link 12, the third link 13, and the proximal link 20 with the winding pulley 14. According to a possible operating mode, a plurality of workpieces (e.g., four workpieces 111, 112, 113, 120) are mounted on the tool, and the plurality of workpieces are arranged so that the cutting wire 51 intersects at most one workpiece at a time during the first through-cut and the second through-cut (which can determine the rotation angle of the rotation step), thereby manufacturing four different links, and for example, the supporting link 11, the second link 12, the third link 13, and the proximal link 20. Therefore, by assembling the workpieces individually to the wire electroerosion machine 50, all the links of the articulated end 10 of the surgical instrument 1 can be manufactured.

[0159] According to a possible mode of operation, the connecting rod is shaped by means of said first and second through-cuts in planes orthogonal to one another.

[0160] According to a possible operating mode, the cutting wire 51 performs more sweeping movements on the portion of the workpiece that will form the at least one first convex regular sliding surface and the second convex regular sliding surface having straight generatrixes orthogonal to each other than the number of sweeping movements adopted to form other parts of the connecting rod, such as the fork portion of the first supporting link and / or the through hole for receiving the corresponding hinge pin.

[0161] The following will describe a method of assembling the surgical instrument 1 .

[0162] A method for assembling a surgical instrument 1 comprises the following steps:

[0163] - inserting the hinge pin 35 into the through hole of the first supporting link 11 and the through hole of the second link 12, and preferably also into the through hole of the third link 13;

[0164] - fixing the operative distal end 41 of the transmission cable 15 with the traction action TR in the termination seat 26 provided in the body of the winding pulley 14 of the second link 12;

[0165] Winding the distal portion adjacent to the operative distal end 41 of the transmission cable 15 on the surface of the winding pulley 14 .

[0166] According to a possible operating mode, the steps of inserting, fixing and winding are carried out in sequence: first the inserting step is carried out, then the fixing step and then the winding step.

[0167] According to a preferred mode of operation, the step of fixing the operative distal end 41 of the transmission cable 15 comprises the following further steps:

[0168] - a configuration of through-going axial alignment (axial alignment relative to the axis of rotation YY of the second link 12) between the terminal seat 26 of the winding pulley 14 of the second link 12 and the assembly window 48 of the fork 34 of the first supporting link 11;

[0169] - Axially inserting the operative distal end 41 of the transmission cable 15 (eg including the enlarged portion) into the assembly window 48 of the fork 34 of the support link 11 and subsequently into the terminating seat 26 of the winding pulley 14 of the second link 12 in axial alignment therewith.

[0170] The step of performing the through-axial alignment configuration may include rotating the winding pulley 14 of the second link 12 about the rotation axis YY defined by the hinge pin 35;

[0171] According to a possible mode of operation, the step of inserting the hinge pin comprises first fixing the swivel pin 35 in the through hole 36 of the second link 12 so that the hinge pin 35 and the winding pulley 14 in the second link 12 are rotatably integral with each other. This step can be performed by elastically clamping the hinge pin 35 to the through hole 36 of the second link 12 by means of the lug 37. Alternatively or additionally, the hinge pin 35 can be keyed to the through hole 36 of the second link 12.

[0172] According to a possible operating mode, the steps of inserting, fixing and winding are carried out in sequence: first the fixing step is carried out, then the winding step and then the inserting step is carried out.

[0173] The method may further comprise the step of arranging the transmission cable 15 in contact with the at least one first sliding surface 17 , 19 and second sliding surface 18 of the support structure 31 .

[0174] The method may further include the step of arranging the transmission cable 15 along the positioning axis of the surgical instrument 1 to secure it to the proximal transmission interface portion of the surgical instrument 1 .

[0175] This method may be repeated multiple times to assemble a corresponding plurality of transmission cables 15 to the second link 12 and / or to the third link 13 .

[0176] The assembly method may be employed to assemble a surgical instrument 1 according to any one of the embodiments described above.

[0177] By virtue of the features described above, whether or not provided in combination with each other in a particular embodiment, it is possible to meet the aforementioned needs, thereby achieving the aforementioned advantages, in particular:

[0178] - the transmission cable can be guided and / or turned without providing holes or guide channels, but instead using sliding abutments formed by convex regular surfaces with generatrixes having a specific direction;

[0179] - in particular, as explained above, making at least two sliding abutments formed by regular surfaces having generatrixes orthogonal to one another, it is possible to obtain an improved control of the trajectory of the transmission cable;

[0180] - the closing force of the opening / closing articulation of the articulated end can be increased, since a larger winding pulley can be made without increasing the size of the articulated end and without providing an abutment suitable for guiding the sliding of the tendon;

[0181] - relative movement occurs between such sliding surfaces and the transmission cable along the longitudinal axis of the transmission cable, generating sliding friction and preventing the transmission cable from driving or being driven in rotation by any of said sliding surfaces;

[0182] - the end seats of the supporting links for their actuating tendons can be slightly offset relative to the centre line;

[0183] - the hinge pin may be rotatably integral with the blade of the second link (if provided);

[0184] - the second link of the hinged end can be an end link forming a free end, or it can also be an intermediate link which is also hinged distally to another distal link;

[0185] - To provide a robust surgical instrument which is also suitable for extreme miniaturization of its articulated end.

[0186] As is well known, the features of the appended claims are combined to form an integral part of the present description.

[0187] In order to meet specific possible needs, a person skilled in the art may make numerous changes and modifications to the embodiments described above and may replace elements with other functionally equivalent elements without departing from the scope of the appended claims.

[0188] Reference numerals list

[0189] 1 surgical or microsurgical instrument 20 another proximal connecting rod

[0190] 2 Positioning rods or shafts for medical or surgical or microsurgical instruments

[0191] The center line of the robot assembly 22 for the process operation

[0192] 10 Articulated end of surgical instrument 23 Proximal transmission interface portion of surgical instrument

[0193] 11 First support link 24 tendon section

[0194] 12 Second connecting rod 25 Blade or cutting edge

[0195] 13 The third connecting rod 26 The end seat of the second connecting rod

[0196] 14 Winding pulley 27 Cantilever of first surface

[0197] 15 Transmission cable for pulling action 28 Cantilever on the second surface

[0198] 16 Power transmission cable 29 Free end

[0199] 17 The first sliding surface of the supporting link, or the first 30 third convex regular sliding surface

[0200] Convex regular surface 31 support structure of hinged end

[0201] 18 A second sliding surface of the supporting link, or a second gripping surface 32

[0202] Convex regular surface 33 Distal free end of the second link

[0203] 19 supports the first sliding surface of the connecting rod, or the first fork 34

[0204] Convex Ruled Surface 35 Hinge Pin

[0205] 36 Holes for pins G Open / Close degrees of freedom

[0206] 37 elastically deformable wall XX longitudinal axis of the device

[0207] 38 Sliding contact angle of the inclined section α of the transmission cable

[0208] 39 The end of the third connecting rodπ The generatrix of the first regular surface

[0209] 40 The through hole of the supporting connecting rod fork υ The generatrix of the second regular surface

[0210] 41 The distal end RR of the transmission cable is in the radial direction of the winding pulley of the second link

[0211] 42 End socket bottom cut wall TR pulling action

[0212] 43 Radial mouth or inlet of the terminal seat WW wire electroerosion machine tool rotation axis

[0213] 44 Circumferential protrusion of the terminal seat

[0214] 45 Contact surface

[0215] 46 Actuating tendon of the first supporting link

[0216] 47 The first supporting connecting rod end seat

[0217] 48 Mounting window for supporting the connecting rod fork

[0218] 50 Wire Electroerosion Machine

[0219] 51 Cutting wire

[0220] 52 Tools

[0221] 111 First Workpiece

[0222] 112 Second Workpiece

[0223] 113 The third workpiece

[0224] 120 Another Artifact

[0225] 151 Outer path of the cable

[0226] 152 Cable return path

[0227] R14 pulley radius

[0228] P1, P2 lateral distance

[0229] PP Pitch axis

[0230] YY deflection axis

Claims

1. A surgical instrument (1) comprising an articulated end portion (10), the articulated end portion comprising: - a first supporting link (11), - a second link (12) which is articulated relative to the supporting link about an axis of rotation (YY), - a transmission cable (15, 16) fixed to the second connecting rod (12); Wherein, the first supporting link (11) comprises: at least one first convex sliding surface (17, 18), the at least one first convex sliding surface being a regular surface having straight generatrixes (π) all parallel to each other, a second convex sliding surface (18), said second convex sliding surface being a regular surface having straight generatrixes (υ) all parallel to each other, And among them: The transmission cable (15, 16) is configured to slide on both the at least one first sliding surface (17, 19) and the second sliding surface (18) of the first support link (11) when the second link (12) rotates relative to the support link (11), The straight generatrix (π) of the at least one first convex regular sliding surface (17, 19) is orthogonal to the straight generatrix (υ) of the second convex regular sliding surface (18).

2. The surgical instrument of claim 1, wherein: - the second link (12) comprises a winding pulley (14), - the transmission cable is wound around the winding pulley (14) of the second link (12), The winding pulley has a radius (R14) which is greater than or equal to the distance between the at least one first sliding surface (17, 19) or the second sliding surface (18) and the centerline of the surgical instrument.

3. The surgical instrument of claim 1, wherein: - the second link (12) comprises a winding pulley (14), - the transmission cable is wound around the winding pulley (14) of the second link (12), The winding pulley protrudes laterally relative to the second sliding surface (18) of the first supporting link (11).

4. A surgical instrument according to any one of the preceding claims, wherein: The second sliding surface (18) is parallel to the rotation axis (YY) between the second link (12) and the first supporting link (11).

5. A surgical instrument according to any one of the preceding claims, wherein: The straight generatrix (π) of at least one first sliding surface (17, 19) and the straight generatrix (υ) of the second sliding surface (18) are all orthogonal to the longitudinal axis of the surgical instrument, and preferably are all orthogonal to the longitudinal axis of the positioning axis (21) of the surgical instrument, and the transmission cable extends along the positioning axis.

6. A surgical instrument according to any one of the preceding claims, wherein: At least one of the at least one first sliding surface (17, 19) and the second sliding surface (18) faces toward a definable longitudinal centerline of the articulated end (10), such as the longitudinal centerline of a positioning axis (21) of the surgical instrument, along which the transmission cable extends.

7. A surgical instrument according to any one of the preceding claims, wherein: The first supporting link (11) comprises at least one cantilever (27, 28) forming a free end, and wherein: At least one of the at least one first sliding surface (17, 19) and the second sliding surface (18) belongs to the at least one cantilever (27, 28) of the first supporting link (11).

8. A surgical instrument according to any one of the preceding claims, wherein: The sliding contact angle (α) between the transmission cable and at least one of the at least one first sliding surface (17, 19) and the second sliding surface (18) does not change for any operational configuration of the articulated end portion (10).

9. A surgical instrument according to any one of the preceding claims, wherein: For any operational configuration of the articulated end (10), the sliding contact angle (α) between the transmission cable and at least one of the at least one first sliding surface (17, 19) and the second sliding surface (18) is less than 90 degrees, and preferably less than 45 degrees, and more preferably less than 30 degrees.

10. The surgical instrument according to any one of the preceding claims, wherein: - for any operational configuration of the articulated end (10), the sum of the sliding contact angle (α) between the transmission cable and the at least one first sliding surface (17, 19) and the sliding contact angle (α) between the same transmission cable and the second sliding surface (18) is less than 180 degrees; and / or wherein: - in at least one operating configuration of the articulated end (10), the sum of the sliding contact angle (α) between the transmission cable and the at least one first sliding surface (17, 19) and the sliding contact angle (α) between the same transmission cable and the second sliding surface (18) is greater than or equal to 180 degrees.

11. The surgical instrument according to any one of the preceding claims, wherein: The at least one first sliding surface (17, 19) and the second sliding surface (18) are longitudinally spaced apart.

12. The surgical instrument according to any one of the preceding claims, wherein: The first supporting link (11) is made as a single component.

13. The surgical instrument according to any one of the preceding claims, wherein: - the articulated end (10) comprises a further proximal link (20) articulated proximally to the first supporting link (11) so as to rotate about a common axis of rotation (PP); - the proximal link (20) comprises a third convex sliding surface (30) for sliding of the transmission cables (15, 16); - the third sliding surface (30) is a regular surface having straight generatrixes, all of which are parallel to the straight generatrix (π) of the at least one first sliding surface (17, 19) or the straight generatrix (υ) of the second sliding surface (18).

14. A surgical instrument according to any one of the preceding claims, wherein: The transmission cable comprises an operational distal end (41) for entraining the second link (12), the distal end being received in a termination seat (26) formed in a disc-shaped carrier of the winding pulley (14); And wherein, preferably, the transmission cable is at least partially made of polymer fibers.

15. The surgical instrument according to any of the preceding claims, comprising an articulation pin (35) extending along the rotation axis (YY), by means of which the second link (12) is articulated relative to the first supporting link (11); in, The hinge pin (35) is rotatably integrated with the winding pulley (14) of the second connecting rod (12).

16. A method for manufacturing at least a supporting link (11) of an articulated end (10) of a surgical instrument (1) by wire electroerosion, The support link (11) comprises at least one first convex regular sliding surface having parallel straight generatrixes and a second convex regular sliding surface having parallel straight generatrixes, the sliding surfaces are both configured to allow the transmission cable to slide thereon, the straight generatrix of the at least one first sliding surface being orthogonal to the straight generatrix of the second sliding surface; The method comprises the following steps: A wire electroerosion machine (50) having a cutting wire (51) is provided; installing at least one workpiece (111) to the machine; Using the cutting wire to perform a first through-cut on the at least one workpiece (111), thereby forming the at least one first sliding surface; rotating the at least one workpiece 90 degrees relative to the cutting wire, A second through-cut is performed on the same at least one workpiece (111) using the cutting wire, thereby forming the second sliding surface.

17. A method for assembling a surgical instrument (1) according to any one of claims 1 to 15, comprising the following steps: Inserting the hinge pin (35) into the through holes of the first supporting link (11) and the second link (12); securing the operative distal end (41) of the transmission cable in a termination seat (26) formed in the body of the winding pulley (14) of the second link; winding a distal section of the transmission cable adjacent to the operative distal end (41) onto the winding pulley (14); Wherein, the fixing step further comprises: A through-going axially aligned structure is arranged between the end seat (26) of the winding pulley (14) of the second connecting rod (12) and the assembly window (48) of the first supporting connecting rod (11), The operative distal end (41) of the transmission cable is axially inserted into the assembly window (48) of the first support link (11) and also axially inserted into the terminating seat (26) of the winding pulley (14) of the second link (12).

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