WO2019131064A1 - Joint member, treatment tool, and method for controlling treatment tool flexure - Google Patents

Abstract

Substantially cylindrical joint members 12 are arranged in parallel substantially coaxial to one another and constitute a treatment tool that allows for flexure, wherein: recesses C11, C12 are formed on one end side of each joint member 12 in an axial direction AD; protrusions P11, P12 are formed on the other end side of each joint member 12 in the axial direction AD; the recesses C11, C12 of one joint member among two adjacent joint members are brought into sliding contact with the protrusions P11, P12 of the other joint member; each joint member 12 is provided with a tube-shaped member 121, and a plate-shaped member 122 disposed across a direction perpendicular to the axial direction AD with respect to the tubular member 121; and each plate-shaped member 122 is provided with a flexure through-hole that passes through the plate-shaped member 122 in the axial direction AD, and a device through-hole that passes through the plate-shaped member 122 in the axial direction AD.

Description

Joint member, treatment tool, bending control method for treatment tool

The present invention relates to a treatment tool used by being inserted into an endoscope or the like, a joint member constituting the treatment tool, and a bending control method of the treatment tool.

As compared with open surgery, endoscopic surgery has the merits of requiring no incision on the surface of the body for surgery or having a very small size, reducing the burden on the body, and leaving no scar of surgery. For example, EMR (endoscopic mucosal resection or ESD (endoscopic submucosal dissection) is used for early gastric cancer or the like which is considered to have a low possibility of metastasis to lymph nodes.
A treatment tool equipped with a high-frequency scalpel or forceps is inserted into the endoscope used for such endoscopic surgery, but the direction of the high-frequency scalpel or forceps should be changed in order to more easily perform the operation. Patent Document 1 discloses a bending treatment tool that has made it possible. The bending treatment tool disclosed in Patent Document 1 includes a forceps or an electric knife attached to the tip of the bending portion, a bending portion that bendably operates the forceps or the electric knife at the tip, bending action of the bending portion, forceps or the like An operation unit for operating the electric knife and a sheath / wire unit for transmitting an operation of the operation unit are provided.
Moreover, in Patent Document 2, a flexible endoscope having a treatment tool includes a manual operation unit and an electric operation unit, whereby a manipulator manipulation device for surgery and a manipulator system for surgery that can be operated without losing the sense of manipulation Is disclosed.

JP, 2015-128534, A JP, 2015-154895, A

The treatment tool needs to arrange the above-mentioned bending structure, a member for driving the same, etc. in a very limited space. According to the technique disclosed in Patent Document 1, it is possible to configure a bendable treatment instrument which can be inserted into an endoscope channel having a diameter of 3.8 mm or less.
The end effector provided at the tip of the treatment tool is the part that performs the treatment under the transendoscope and has various functions such as biopsy forceps, grasping forceps, high frequency snare, high frequency knife, local injection needle, peeling forceps Used. When performing treatment with such an end effector, a certain amount of load may be applied to the treatment tool tip. For example, it is a load applied at the time of grasping operation of grasping forceps or excision operation of a knife.
As in the technique disclosed in Patent Document 1, by providing the bending portion in the treatment tool, it is expected that, for example, an operation such as grasping and lifting a tissue with a grasping forceps can be performed with a higher degree of freedom. For that purpose, it is desirable to increase the load that can be lifted by the tip of the treatment tool.
However, in the bending treatment tool described in Patent Document 1, each of the holes (device through holes, through which a wire or the like is inserted, with respect to a member whose basic mode is cylindrical (solid), the hinge member constituting the bending portion It is formed by providing each convex part and recessed part for making the bending through-hole) and bending operation. Therefore, when the small diameter wire used in the small diameter treatment tool is used, the weight of the hinge member increases, and the weight of the hinge member increases the load that can be lifted at the tip of the treatment tool, ie, For example, the inventors have found a problem that it is difficult to increase the force for gripping and pulling the mucosal tissue with a grasping forceps.
Further, in the hinge member described in Patent Document 1, a cylindrical (solid) member is processed while maintaining the strength of the member to shorten the axial distance between the device through hole and the bending through hole. The inventors found the problem that it became difficult. Furthermore, in the hinge member described in Patent Document 1, when the bent portion is bent, the wire inserted into the hole contacts along the entire inner wall in the axial direction of the hole. This increases the sliding friction resistance between the wire and the hinge member, requires a large wire pulling force, reduces the load that the treatment tool tip can lift than the maximum load that the wire can pull, and holds the mucosal tissue with a sufficient pulling force. The inventors found that there is a problem that it is difficult to do.
In addition, in the treatment tool used for flexible endoscopic surgery, although the diameter is small, since the mucosal tissue is lifted while being bent while being bent, the member of the bent portion is not deformed even when a large load is applied by the wire pulling. Strength is required. For this reason, it is desirable that the member of the bent portion be made of a strong metal member such as SUS. However, if it is attempted to form the hinge member having the above structure in Patent Document 1 with metal so that the outer diameter is 3.8 mm or less, processing with high accuracy is difficult, and the manufacturing cost is increased. The inventors found a problem.

SUMMARY OF THE INVENTION In view of the above-described point, the present invention provides a joint member of a bendable treatment tool capable of withstanding the load due to bending and mucosal tissue traction while being thin enough to be inserted into an endoscope channel, and the joint member It is an object of the present invention to provide a treatment tool used and a bending control method of the treatment tool.

(Configuration 1)
A substantially cylindrical joint member arranged coaxially to each other to constitute a bendable treatment tool, comprising: a tubular member; and a plate disposed across the inside of the tubular member with respect to the tubular member A plate-like member comprising: a bending through-hole penetrating the plate-like member in the axial direction; and a device through-hole penetrating the plate-like member in the axial direction; A recess formed on one end side in the axial direction, and a protrusion formed on the other end side of the joint member in the axial direction and in sliding contact with the recess formed on the adjacent joint member; Joint member provided with

(Configuration 2)
A pair of recesses are formed on one end side of the joint member in the axial direction so as to face in the radial direction of the joint member, and on the other end side in the axial direction of the joint member, in the radial direction of the joint member The joint member according to Configuration 1, wherein a pair of the convex portions are formed in order to do so.

(Configuration 3)
The joint member according to Configuration 2, wherein a line connecting the pair of concave portions and a line connecting the pair of convex portions are substantially parallel.

(Configuration 4)
The joint member according to Configuration 2, wherein a relative angle between a line connecting the pair of concave portions and a line connecting the pair of convex portions is approximately 90 °.

(Configuration 5)
The joint member according to Configuration 2, wherein a relative angle between a line connecting the pair of concave portions and a line connecting the pair of convex portions is approximately 120 °.

(Configuration 6)
The joint member according to Configuration 5, further comprising a bending restricting member that restricts bending due to sliding contact between two joint members adjacent to each other to bending to one side.

(Configuration 7)
The pair of plate-like members is configured as a pair of the protrusions are configured as a part of the outer periphery of the tubular member, and the plate-like member further includes a notch that engages with the pair of the protrusions. The joint member according to any one of the configurations 2 to 6, which is engaged with the convex portion of.

(Configuration 8)
The joint member according to Structure 7, wherein the plate-like member further includes a slit extending from the notch portion to the bending through hole or the device through hole.

(Configuration 9)
In any of the configurations 1 to 8, any one of the slits 1 to 8 wider than the diameter of the drive member is further formed at a position on the inner side of the bending due to sliding contact between two joint members adjacent to each other in the outer peripheral portion of the tubular member. Joint member according to claim 1.

(Configuration 10)
The recess and the protrusion are formed on one end side in the axial direction of the joint member so as to face in the radial direction of the joint member, and on the other end side in the axial direction of the joint member, the radial direction of the joint member The joint member according to Configuration 1, wherein the protrusion and the recess are formed to face each other.

(Configuration 11)
10. The joint member according to configuration 10, wherein a line connecting the recess and the protrusion on one end side in the axial direction of the joint member and a line connecting the recess and the protrusion on the other end side are substantially parallel.

(Configuration 12)
The joint according to Configuration 10, wherein a relative angle between a line connecting the recess and the protrusion on one end side in the axial direction of the joint member and a line connecting the recess and the protrusion on the other end is approximately 90 °. Element.

(Configuration 13)
The joint according to Configuration 10, wherein a relative angle between a line connecting the recess and the protrusion on one end side in the axial direction of the joint member and a line connecting the recess and the protrusion on the other end is approximately 120 ° Element.

(Configuration 14)
The joint member according to any one of constitutions 1 to 13, further comprising a bending angle limiting member for limiting an angle of bending due to sliding contact between two joint members adjacent to each other to less than 30 °.

(Configuration 15)
The bending angle limiting member is a protrusion formed on the convex portion, the tubular member, or the plate-like member, and the protrusion abuts with an adjacent joint member as the treatment tool is bent, and the adjacent members mutually adjoin each other. 14. The joint member according to configuration 14 wherein the angle of flexion of the two joint members is limited to less than 30 °.

(Configuration 16)
The joint member according to any one of the constitutions 1 to 15, wherein the concave portion and the convex portion are integrally configured as a part of an outer peripheral portion of the tubular member.

(Configuration 17)
The treatment tool formed by mutually assembling | attaching the joint member in any one of the structures 1-16.

(Configuration 18)
A plurality of tubular members having a recess formed on one end side in the axial direction and a protrusion formed on the other end, wherein the recess of one tubular member of the tubular members adjacent to each other is the protrusion of the other tubular member And a plate-like member having a plurality of tubular members configured to be bendable, a bending through hole penetrating in the axial direction of the tubular member, and a device through hole penetrating in the axial direction of the tubular member. A member, which is a plate-like member disposed transverse to the inside of the tubular member with respect to at least one of the tubular members.

(Configuration 19)
The treatment tool according to the configuration 17 or 18, wherein a plurality of the bending through holes are formed in the plate-like member, and the plurality of driving members are respectively inserted into the plurality of the bending through holes. A bending control method for a treatment tool having the basic bending axis and the drive member corresponding to each basic bending axis, the proximal end portion of the bending portion of the treatment tool being substantially in the axial direction of the treatment tool In a multi-dimensional oblique coordinate system having coordinate axes corresponding to the basic bending axes on orthogonal planes, vector decomposition of a target position based on an input bending instruction into coordinate axis vectors along the coordinate axes, and the coordinate axis vectors Calculating a pulling amount of the drive member corresponding to the basic bending axis corresponding to each coordinate axis on the basis of.

(Configuration 20)
The plurality of basic bending axes are three basic bending axes mutually having a relative angle of 120 °, and the multidimensional oblique coordinate system is represented by three coordinate axes mutually having a relative angle of 120 °. The bending control method of a treatment tool according to configuration 19, which is an oblique coordinate system.

(Configuration 21)
In the calculation of the amount of pulling, the step of calculating the amount of change in the path length of the drive member before and after bending of the treatment tool, and the amount of elongation of the drive member due to the load applied to the drive member when the treatment tool is bent The bending control method for a treatment tool according to Configuration 19 or 20, comprising the steps of: calculating the amount of pulling based on the amount of change in the path length and the amount of extension of the drive member.

According to the present invention, since the inside is basically formed by the hollow tubular member and the plate member, the weight of the joint member can be lightened while maintaining the strength. Further, since the bending through holes are formed in the plate-like member, the contact range of the driving member such as a wire and the bending through holes can be reduced, and the sliding friction resistance can be reduced. As a result, it is possible to configure a bendable treatment device that can sufficiently withstand the load due to tissue traction while being thin enough to be inserted into the endoscope channel.

The perspective view which shows the outline of the treatment tool of embodiment concerning this invention The figure which shows the bending state of the bending part of the treatment tool of embodiment Perspective view showing a joint member Front view showing a tubular member Side view showing a tubular member Top view showing a plate-like member Diagram showing the sliding (bending) state between two joint members Diagram showing the sliding (bending) state between two joint members Front view showing the proximal member Side view showing the proximal member Front view showing the tip member Side view showing the tip member Sectional view mainly showing the structure of a bending portion of a treatment tool Explanatory drawing which shows the positional relationship of the basic bending axis of a treatment tool, and a drive member (wire) The figure which shows the example of the joint member provided with the bending limitation member The figure which shows the example of the joint member provided with the bending limitation member A figure showing an example of a treatment tool provided with grasping forceps as an end effector A diagram showing an example of a joint member in which a basic bending axis is orthogonal The figure which shows the example of the joint member whose basic bending axis is parallel The figure which shows the example of the joint member in which the recessed part and the convex part are formed in the one end side, and the convex part and the recessed part are formed in the other end side. The figure which shows the state of an internal drive member (wire) in the sliding contact (bending) state of a joint member The figure which shows the example of the joint member in which the slit for contact suppression with a drive member (wire) is formed Diagram showing another example of joint member Diagram showing another example of joint member Front view showing an outline of an operation unit and an electric drive Block diagram schematically showing the configuration of a motorized drive Diagram showing the basic flow of the bending control algorithm of the treatment tool Explanatory drawing about the point which expresses a target position on a predetermined coordinate system for bending control of a treatment tool. Explanatory drawing about the point which expresses a target position on a predetermined coordinate system for bending control of a treatment tool. Explanatory drawing about the point which expresses a target position on a predetermined coordinate system for bending control of a treatment tool. An illustration of vector decomposition in a multidimensional oblique coordinate system An illustration of vector decomposition in a multidimensional oblique coordinate system Explanatory drawing about the change of the path length of a drive member (wire) in bending of a bending part Explanatory drawing about the pulling amount of a drive member (wire)

Hereinafter, embodiments of the present invention will be specifically described with reference to the drawings. In addition, the following embodiment is one form at the time of embodying this invention, Comprising: This invention is not limited within the range.

First Embodiment
FIG. 1 is a perspective view showing an outline of a treatment tool according to an embodiment of the present invention. Moreover, FIG. 2 is a perspective view which shows a bending part and an end effector part. In addition, although the bending part 1 and the sheath part 2 are coat | covered with a polymer tube etc. so that it may demonstrate later, in FIG.1 and FIG.2, etc., a polymer can be understood so that the structure of a bending part may be understood. It is a figure in the state where there is no covering by a tube etc.
As a basic aspect of the treatment tool T according to the present embodiment, the end effector 5, the bending portion 1 for bending the end effector 5 in a desired direction, and the bending portion 1 of the joint member pass through the bending portion 1 A tubular sheath portion 2 internally provided with a drive member (drive wire) for bending and a core wire for driving an end effector, and an operation portion 3 for performing operations such as bending by pulling the drive wire and core wire Have. In addition, although the drive wire is used as a specific example of a drive member here, a drive member is not limited to a metallic wire.
The treatment tool T is used by being inserted into an endoscope channel, and the outer diameter of the bending portion 1 or the sheath portion 2 is 3.8 mm or less, preferably 2.6 mm or less.

As shown in FIG. 2, the bending portion 1 is provided with a proximal end member 11 and a distal end member 13 respectively provided on the proximal end side and the distal end side, and a plurality of joint members 12 combined so as to bend while sliding against each other. And consists of
As described below, in the joint member 12, the direction of the bending axis (line connecting the convex portions) on one end side in the axial direction is different from the direction of the bending axis (line connecting the concave portions) on the other side. By connecting the joint members 12 as described above, they are articulated and can be bent in any direction as a whole as shown in FIG.

FIG. 3 is a perspective view showing the joint member 12.
The joint member 12 has concave portions C11 and C12 formed on one end side in the axial direction AD so as to face in the radial direction of the joint member, and convex portions P11 and P12 on the other end side so as to face in the radial direction of the joint member. Is formed. Recesses C11 and C12 of one joint member in two joint members 12 adjacent to each other can come into sliding contact with the projections P11 and P12 of the other joint member (see FIGS. 7A and 7B). Thus, two adjacent joints are formed by a unit body formed by the two joint members 12 in which the concave portions C11 and C12 of one joint member and the convex portions P11 and P12 of the other joint member are slidably combined. The member 12 is configured to be bendable.
The joint member 12 includes a tubular member 121 and a plate-like member 122 disposed perpendicularly to the tubular member 121 in the axial direction AD. In the present embodiment, the plate-like member 122 is disposed substantially perpendicular to the axial direction AD of the tubular member 121, but the concept of the present invention is not limited to this. More specifically, “disposed perpendicularly to the axial direction AD” is not limited to the plate member 122 being provided substantially perpendicular to the axial direction AD, “ What is “crossed” in the direction perpendicular to the axial direction AD, that is, those crossing the inside of the tubular member 121 may be used (except in the longitudinal direction in the axial direction AD).
The installation angle of the plate member 122 with respect to the axial direction AD of the tubular member 121 is preferably in the range of 90 ± 20 [deg], and more preferably in the range of 90 ± 10 [deg]. Most preferably, the installation angle of the plate member 122 with respect to the axial direction AD is 90 degrees.

4 and 5 are a front view and a side view showing the tubular member 121. FIG.
The tubular member 121 is a member having a cylindrical (hollow) basic aspect. The concave portions C11 and C12 are formed on one end side of the tubular member 121, and the convex portions P11 and P12 are formed on the other end side.
The concave portions C11 and C12 are formed by cutting out a part of the cylindrical outer peripheral portion in a substantially arc shape. As shown in FIGS. 7A and 7B, the base end surfaces TS on both sides of the concave portions C11 and C12 are cut at a predetermined angle β [deg]. As understood from FIGS. 7A and 7B, it is intended not to interfere with the adjacent joint member during the bending operation. The angle β is a relative angle between the surface in contact with the side surface of the tubular member 121 and the proximal end surface TS, as shown in FIG. 7A.
Two adjacent joint members are in sliding contact with the concave portions C11 and C12 of one joint member and the convex portions P11 and P12 of the other joint member, and are bent at a certain bending angle α [deg]. The bending angle α is an angle at which one joint member of two adjacent joint members slides relative to the other joint member from a straight state in which the central axes of two adjacent joint members coincide with each other. It is represented by an angle formed by the central axis (L3 in FIG. 7B) of the joint member and the central axis (L4 in FIG. 7B) of one joint member.
In order not to interfere with the adjacent joint member at the time of bending operation, β <90−α [deg]. In the present embodiment, β is about 50 [deg] with respect to α = about 22.5 [deg].
The convex portions P11 and P12 are also formed as a part of the cylindrical outer peripheral portion, and as shown in FIGS. 7A and 7B, have approximately arc-shaped protruding portions formed to be in sliding contact with the concave portions C11 and C12. At its root portion, it engages with a plate-like member 122 described below. More specifically, the “substantially arc-shaped protruding portion” is a shape obtained by cutting the upper portion of the arc so as to be substantially parallel to the end portion on the upper side of the tubular member where the convex portion is not formed. . The “upper part” is the upper part of the tubular member 121 where the side on which the concave parts C11 and C12 are formed is the lower part and the side on which the convex parts P11 and P12 are formed is the upper part. The position to be cut is preferably on the upper side of the approximate center of the approximate arc of the convex portions P11 and P12. The relative angle between the cut portion of the upper portion of the arc and the end portion of the upper side of the tubular member where the convex portion is not formed is preferably in the range of ± 20 deg, and in the range of ± 10 deg. Is more preferable. It is most preferable that the cut portion at the top of the arc and the portion where the convex portion is not formed at the end face on the upper side of the tubular member be parallel.
The convex portions P11 and P12 are formed in an arc shape in which the vicinity of the upper portion is cut, so that the sliding resistance is reduced by reducing the contact range with the concave portions C11 and C12.
In addition, as the bending angle limiting member that engages the plate-like member 122 with the convex portions P11 and P12 and limits the angle of bending α due to sliding contact between two adjacent joint members to less than 30 °. A functional projection AL is provided. As shown in FIGS. 7A and 7B, with the bending of the adjacent joint member, the bending angle α of the two joint members adjacent to each other is less than 30 ° by the abutment of the adjacent joint member and the projection AL. It is limited. Here, although the example in which the protrusions AL as the bending angle limiting members are provided on the convex portions P11 and P12 is taken as an example, the protrusions AL are different points of the tubular member according to the difference in the configuration of the joint members. Alternatively, it may be provided on a plate-like member or the like.
In order to increase the bending angle α per joint member, it can be realized by forming the substantially arc-shaped portions of the convex portions P11 and P12 to be longer (so that the central angle γ of the substantially arc-shaped portions becomes larger) . When the bending angle α per joint member increases, the bending R of the bending portion can be reduced, so even when using an endoscope having an optical system with a focal length of several millimeters, such as a flexible endoscope, It is possible to move the bending treatment tool in the near range from the lens where the However, if the bending angle α per joint member is made too large, the tube covering the bending portion is sandwiched between the two joint members to inhibit the movement of the bending portion, or the substantially circular portions of the convex portions P11 and P12 By increasing the central angle γ of the arc-shaped portion, the root portions of the convex portions P11 and P12 may become thin and strength may be insufficient. Therefore, in the present embodiment, α is limited to less than 30 ° by the projection AL. In addition, when there is no possibility of such a bad effect, you may make bending angle (alpha) per joint member 45 degrees, 30 degrees, etc. The bending angle α is preferably 10 [deg] or more, more preferably 20 [deg] or more. The bending angle α is preferably 40 [deg] or less, more preferably 30 [deg] or less, still more preferably less than 30 [deg], and still more preferably 25 [deg] or less.
Further, the bending angle α may be 22.5 °.
In the case where the bending angle α is 45 °, the bending portion can be bent from a straight state to about 90 ° in a configuration in which the same “basic bending axis” appears twice, which will be described later. Similarly, in the case where the bending angle α is 30 ° and 22.5 °, the bending portion can be bent to 90 ° in a configuration in which the same “basic bending axis” appears three times and four times, respectively.
Further, by forming the central angle γ of the substantially arc-shaped portions of the convex portions P11 and P12 and the central angle of the circular arc portions of the concave portions C11 and C12 to be 180 degrees or more, the concave portions C11 and C12 and the convex portions P11, It is possible to prevent P12 from disengaging in the axial direction (the AD direction in FIG. 3).
The tubular member 121 can be manufactured with high processing accuracy while being inexpensive, for example, by laser cutting of a standard stainless steel (SUS) pipe. By manufacturing from a pipe member in this manner, the circumferential thickness can be made uniform. For example, even in the case where the wall thickness is formed as thin as 0.2 mm, the whole including the convex portions P11 and P12 can be easily formed to a uniform thickness by manufacturing based on the pipe member of 0.2 mm. can do. By being able to form the thickness uniformly, stable strength can be obtained, and it is possible to form a concave or a convex that does not deform even when a load necessary for gripping the mucosal tissue is applied. In addition, since manufacturing with high processing accuracy is possible, as a result, the sliding resistance is reduced when the concavo-convex portion is engaged and moved by sliding, and the control accuracy by pushing and pulling the drive wire of the bent portion is reduced. You can raise it.

FIG. 6 is a top view showing the plate member 122. As shown in FIG.
The plate-like member 122 is a plate having a circular basic form, and is provided with a device through hole H1 at the center and six bending through holes H2 at its periphery. The device through hole H1 is a hole through which a core wire for controlling the opening and closing of a forceps which is an end effector, an electrode wire of a high frequency knife which is an end effector, a solution flow passage for injecting a solution under the mucous membrane, etc. . The bending through hole H2 is a hole through which a driving member represented by a wire or the like for bending the bending portion is inserted. The treatment tool T according to the present embodiment has three “basic bending axes” having a relative angle of 120 ° to each other as described later, and three corresponding to the respective “basic bending axes”. The drive wire of the Accordingly, the drive wire passes through three holes in the bending through holes H2 of the plate-like member 122, but as shown in FIG. 6, six bending through holes H2 are spaced 60 ° apart at point-symmetrical positions. By providing them, the plate-like member 122 can be made common. The bending through hole H2 may be integrated with the notch 1221.
When individual plate-like members 122 (three types) corresponding to three “basic bending axes” are used, the number of bending through holes H2 may be three. In this case, instead of being able to share parts, since the bending through hole H2 can be formed larger and a thicker drive wire can be adopted as compared to the case where the bending through holes H2 are six, lifting at the bending portion It is possible to increase the load that can be
Notches 1221 are formed on both sides of the plate-like member 122 so as to engage with the protrusions P11 and P12 of the tubular member 121. Further, a slit S1 extending from the notch 1221 to the device through hole H1 is formed in one notch 1221. The presence of the slits S1 improves the workability at the time of fitting the plate-like member 122 to the convex portions P11 and P12 of the tubular member 121. Here, the slit S1 is from the notch 1221 to the device through hole H1 as an example, but it may be a slit from the notch to the bending through hole depending on the difference in the structure of the joint member. .
The plate-like member 122 can be manufactured, for example, by laser cutting or pressing an SUS plate which is a standard product, and can be accurately and inexpensively processed. Thereby, a stable strength can be obtained, and a device through hole and a bending through hole can be formed which do not deform even when a load necessary for gripping mucosal tissue is applied. Since the hole diameter can be accurately processed, the clearance between the hole diameter and the diameter of the drive wire or core wire can be reduced, and the wire diameter can be maximized.

The joint member 12 is configured by fitting the tubular member 121 and the plate-like member 122 described above. The process of welding, adhesion, etc. is unnecessary in fitting of both.
In the joint member 12 of the present embodiment, as shown in FIG. 3, the relative angle between the line L1 connecting the pair of concave portions C11 and C12 and the line L2 connecting the pair of convex portions P11 and P12 is approximately 120 °. .
Therefore, by arranging the joint members 12 having the above construction in a row, each joint member 12 is provided while being rotated by 120 °. Thereby, in a state where the bending portion 1 is straight, a bending axis in the same direction appears every three joint members 12 are arranged, and in the present invention, a bending axis in the same direction is referred to as a "basic bending axis". Call it In the bending portion 1 of the present embodiment, three “basic bending axes” having a relative angle of 120 ° to each other are provided.
Note that the “line L1 connecting the pair of concave portions C11 and C12” and the “line L2 connecting the pair of convex portions P11 and P12” are respectively connected to the base end side of the joint member 12 when the joint member 12 is connected. It is a bending axis on the tip side. As in the present embodiment, when the pair of convex portions P11 and P12 and the pair of concave portions C11 and C12 are formed in a substantially arc shape, L1 and L2 are straight lines passing substantially the centers of the arcs.

8 and 9 are a front view and a side view showing the proximal end member 11, respectively.
The base end member 11 is a cylindrical (hollow) member in a basic aspect, and convex portions P21 and P22 are formed on one end side thereof. The convex portions P21 and P22 are engaged with the concave portions C11 and C12 of the joint member 12 (tubular member 121), and the convex portions P21 and P22 of the base end member 11 and the projection AL are joint members 12 (tubular member 121). Is the same as the convex portions P11 and P12 and the projection AL.
The proximal end member 11 is a member that connects between the joint member 12 and the sheath portion 2. The end face of the coil tube of the sheath portion 2 and the end face of the proximal end side of the proximal member 11 are joined by welding or the like. When a multi-lumen tube is used in the sheath portion 2, the position of the bending through hole H2 of the plate-like member 122 provided in the joint member 12 and the position of the driving wire penetrating hole in the sheath portion 2 coincide with each other. Preferably, the side surface of the multi-lumen tube in the sheath portion 2 and the inner wall of the proximal member 11 are fixed with an adhesive or the like. By fixing the multi-lumen tube to the proximal end member 11 with an adhesive or the like, the multi-lumen tube does not rotate relative to the proximal end member 11 even when the entire treatment tool is bent, etc. Between the end members 11, it is possible to prevent an increase in frictional resistance due to twisting of the drive wire. The hole H3 formed in the proximal end member 11 is an inlet for an adhesive for the bonding.
By making the inner diameter of the proximal end member 11 larger than the outer diameter of the multi-lumen tube, the multi-lumen tube can be introduced to the inner cavity of the proximal end member 11, bonding with the proximal end member 11 while confirming the position of the drive wire. It's easy to do.

10 and 11 are a front view and a side view showing the tip end member 13.
The tip member 13 is a cylindrical (hollow) member in a basic aspect, and the concave portions C31 and C32 are formed on one end side thereof. The concave portions C31 and C32 are engaged with the convex portions P11 and P12 of the joint member 12 (tubular member 121), and the configuration of the base end side of the distal end member 13 is the proximal end of the joint member 12 (tubular member 121) It is similar to the configuration of the side.
A plate-like member 122 is attached to the tip end member 13, and a notch portion 131 and an engagement concave portion 132 for that purpose are formed. The engagement recess 132 is engaged with the notch 1221 of the plate member 122 at this portion. The notch 131 is a triangular notch formed on the side surface of the tip member 13 so that the plate member 122 can be introduced into the inside of the tip member 13.
The tip member 13 is a member for attaching an end effector, and in order to fix the end effector, the end face of the outer edge portion on the tip side is preferably a circumferential shape. When the end effector is an electrode knife, it is preferable to fix a pin 4 (see FIG. 12) made of a fluorine resin having heat resistance and insulation and ceramics such as zirconia and alumina to the end face.

FIG. 12 is a cross-sectional view mainly showing the structure of the bending portion 1 of the treatment tool T. As shown in FIG.
As described above, the bending portion 1 is configured by the plurality of joint members 12 provided in series and the base end member 11 and the tip end member 13 provided on the base end side and the tip end side thereof.
The end member 13 is provided with an end effector (electrode knife 5 in the example of FIG. 12), and the electrode wire CW of the electrode knife 5 is inserted into a device through hole H1 provided at the center of each plate member 122 Ru.
Further, three drive wires (two wires W1 and W2 are drawn in FIG. 12) are respectively inserted into the bending through holes H2 of the plate-like members 122. The three drive wires W1 to W3 are fixed by caulking the SUS tube 8 through the drive wires W1 to W3 after inserting the plate-like member 122 provided in the tip end member 13.
The bending portion 1 and the sheath portion 2 are preferably covered by the polymer tube PT. By using a flexible polymer tube, it is possible to minimize the bending radius and reduce the load on the drive wires W1 to W3 at the time of bending. Moreover, it can suppress that the recessed part and convex part of the two joint members 12 which are engaged shift or remove | deviate from the radial direction of a tubular member. In addition, also by using a rigid member such as a SUS wire as the drive wire, it is possible to suppress that the concave portion and the convex portion of the two joint members 12 engaged are shifted or deviated in the radial direction of the tubular member. be able to.
In covering the bending portion 1 and the sheath portion 2, a fluorine resin having a high density is used for covering the sheath portion 2, and the resin density of the tube is gradationed so that the portion covering the bending portion 1 becomes porous. It is preferable to use a tube, in particular, since it can maintain the necessary electrical insulation property with an electrode knife or the like and can bend the tip with a minimum radius without disturbing the bending of the bending portion.

The electrode wire CW and the drive wires W1 to W3 pass through the inside of the sheath portion 2 and reach the operation portion 3.
The sheath portion 2 includes a coil coil tube which is a flat coil or liner blade tube made of SUS or the like, a lumen tube inserted into the coil tube, a drive wire inserted into the lumen tube, and a device through hole It is comprised by the electrode wire etc. which pass through a hole. As the lumen tube, a multi-lumen tube made of a fluorocarbon resin with low sliding friction resistance and a plurality of single lumen tubes are used. The drive wire and the electrode wire are inserted through the lumen tube. By doing this, it is possible to prevent the friction of the drive wire when pushing and pulling the drive wire, the meandering of the drive wire unintended, and the breakage of the wire, and the controllability of the bent portion can be improved. Since the electrode wire and the core wire are often larger in diameter than the drive wire, they may be inserted into the lumen tube or may be disposed as they are in the coil tube. By inserting the tube into the lumen tube, it is possible to expect prevention of breakage of the wire and improvement in controllability of push and pull as in the case of the drive wire. In the case of using a plurality of single lumen tubes, a dummy wire or the like may be packed in the coil tube in order to prevent the meandering in the sheath of the single lumen tube itself. In this way, even in the case of a single lumen tube, the path of the wire in the sheath can be uniquely defined. When using a round wire coil, flat wire coil, or inner flat coil made of SUS etc. for the single lumen tube, compression of the lumen tube and sheath part can be prevented even if the drive wire is pulled, so the control of the bending part is improves. In addition, a PTFE tube may be used as a single lumen tube through which the electrode wire is inserted. The sliding resistance of the electrode wire is reduced and the effect of insulation is also obtained.

FIG. 13 is a conceptual explanatory view showing the positional relationship between the basic bending axes BA1 to BA3 and the drive wires W1 to W3 in the treatment tool T of the present embodiment. The figure is an explanatory view from a cross-sectional viewpoint in the bending portion 1.
As described above, the treatment tool T of the present embodiment has three basic bending axes BA1 to BA3 having a relative angle of 120 ° to one another, and three corresponding to the respective basic bending axes BA1 to BA3. Drive wires W1 to W3 of FIG. That is, the driving wire W1 corresponds to the basic bending axis BA1, the driving wire W2 corresponds to the basic bending axis BA2, and the driving wire W3 corresponds to the basic bending axis BA3. Each drive wire corresponding to each basic bending axis is disposed at the position farthest from the basic bending axis, and thus generates a large moment with respect to the basic bending axis.
In the example of FIG. 13, when it is desired to bend the bending portion 1 upward, the drive wire W 1 may be pulled, and when it is desired to bend the bending portion 1 downward, the driving wires W 2 and W 3 may be the same amount. By pulling, it can be bent downward as a synthetic component. As described above, according to the pulling amount of each of the drive wires W1 to W3, bending at each of the basic bending axes BA1 to BA3 is combined, and the bending portion 1 can be bent in any direction as a whole.
In order to make the control of the bending angle accurate and to facilitate the control, it is preferable to make the bending control with respect to each basic bending axis BA1 to BA3 independent. In FIG. 13, when the drive wire W1 is pulled, basically the bending at the basic bending axis BA1 is made to occur, but the bending is also caused to the basic bending axes BA2 and BA3. That is, by pulling the drive wire W1, it is made to be bent to the upper right in the middle step of FIG. 13 and to be bent to the upper left in the lower step. The occurrence of such bending at each basic bending axis becomes a factor that complicates control of the bending angle. In addition, since the bending in the basic bending axis other than the basic bending axis corresponding to the drive wire, ie, the bending in the basic bending axes BA2 and BA3 when the wire W1 is pulled, the moment is small and the operation has uncertainty. It is also a factor that makes accurate bending control difficult.
In order to prevent this, as illustrated in FIG. 14A and FIG. 14B, a bending restricting member BL is provided which restricts bending due to sliding contact between two adjacent joint members to bending to one side. It is also good. The bending restriction member BL in the present embodiment is formed integrally with the tubular member 121 on the proximal end side of the tubular member 121. That is, it is formed to extend a part of the cylindrical shape of the tubular member 121.
By providing the bending restricting member BL, in the upper stage of FIG. 13, it does not bend downward around the basic bending axis BA 1, and in the middle stage, it does not bend obliquely upward right around the basic bending axis BA 2. In the above, there is no bending in the upper left oblique direction around the basic bending axis BA3. If it says in the above-mentioned example, when drive wire W1 is pulled, it can be set as bending only in basic bending axis BA1. As a result, the bending control for each basic bending axis BA1 to BA3 can be made independent, and the control of the bending angle can be made accurate and easy.

As described above, according to the treatment tool T of the present embodiment, the joint member 12 includes the tubular member 121 whose inside is basically hollow and the plate-like member 122 formed separately from the tubular member 121. Being configured, weight can be lightly formed.
Further, since the bending through hole H2 is formed in the plate-like member 122, the contact range with the driving wires W1 to W3 can be reduced, and the bending through hole H2 is generated between the driving wires W1 to W3 and the bending through hole H2. It is possible to reduce the frictional resistance.
By these, the loss of wire traction force can be reduced, and the load which the treatment tool lifts can be maximized.
Further, as described above, the tubular member 121 and the plate-like member 122 can be manufactured inexpensively by laser cutting a SUS pipe or a SUS plate. Furthermore, the manufacturing cost can be further reduced by setting the plate member to a press. Assembling of the joint member is possible only by physical fitting, and steps such as welding and bonding are unnecessary. At the same time, various outer diameter dimensions and thicknesses can be selected from general-purpose products such as SUS pipes and SUS plates, and the outer diameter and the inner diameter of the joint member 12 can be freely changed. For this reason, even as a single-use (disposable) product preferable for a medical treatment tool, it is possible to provide treatment tools of various specifications at a practical cost.
Further, as described above, since the tubular member 121 and the plate-like member 122 can be formed with high accuracy and stable strength can be obtained by this, even when applying a load necessary to grasp mucosal tissue. It is possible to use a joint member that is not easily deformed (a joint member that can maximize the load that the treatment tool lifts).
The tubular member 121 or the plate-like member 122 is preferably made of SUS in consideration of strength, manufacturing cost, and processing. The tubular member 121 or the plate-like member 122 may be made of metal such as titanium, aluminum, brass, nickel alloy, or ceramic depending on the application as long as sufficient strength of the joint member can be obtained against the force applied to the treatment tool tip. You may form by members, such as. The tubular member 121 and the plate member 122 may be made of different materials.
The above points are the same for the proximal end member 11 and the distal end member 13.

Further, according to the treatment tool T of the present embodiment, the relative angle between the line connecting the pair of recesses (L1 in FIG. 3) and the line connecting the pair of protrusions (L2 in FIG. 3) is approximately 120 °. Since the number of drive wires can be made three, it is possible to reduce the number of drive wires as much as possible as it can be bent in any direction.

In this embodiment, although the electrode scalpel 5 is taken as an example as an end effector, it is not limited to this, For example, as shown in FIG. 15, forceps 6 etc. can be used. The end effector is a part that performs trans-endoscopic treatment, and may have various functions such as biopsy forceps, grasping forceps, high frequency snares, high frequency knives, local injection needles, and peeling forceps.

Further, in the present embodiment, the relative angle between a line connecting a pair of concave portions (L1 in FIG. 3) and a line connecting a pair of convex portions (L2 in FIG. 3) is approximately 120 °. Although a book is taken as an example, the relative angle of the line connecting the concave portion and the line connecting the convex portion can be set arbitrarily. That is, in the present invention, the concept "consisting of a joint member consisting of a tubular member whose inside is basically hollow and a plate-like member" is used for those having an arbitrary number of drive wires. be able to. For example, as shown in FIG. 16, the relative angle between the line L1 connecting the concave portions and the line L2 connecting the convex portions may be approximately 90 degrees. In this case, basically, the number of drive wires is four, but it is also possible to drive by three drive wires.
When it is not necessary to make the bent portion bendable in any direction (for example, when it is possible to rotate the sheath portion, etc.), as shown in FIG. The line L2 connecting the two may be substantially parallel.
Further, as a joint member used for one treatment tool, it is not necessary to use the same relative angle between the line L1 connecting the concave portions and the line L2 connecting the convex portions, but the line L1 connecting the concave portions, It is also possible to mix and use joint members having different relative angles of the line L2 connecting the convex portions.

In this embodiment, a pair of concave portions are formed on one end side in the axial direction of the joint member, and a pair of convex portions are formed on the other end side. However, the present invention is not limited to this. As shown in FIG. 18, the concave portion C41 and the convex portion P41 are formed on one end side of the joint member in the axial direction so as to face in the radial direction of the joint member, and on the other end side to oppose in the radial direction of the joint member. The convex part P42 and the concave part C42 may be formed on
In this case, the relative angle of the line connecting the recess and the protrusion on the one end side in the axial direction of the joint member and the line connecting the recess and the protrusion on the other end is the same as described above. .
In the present embodiment, although the convex portion is formed in the tubular member as an example, the convex portion may be formed on the plate-like member side. A convex portion vertically erected from the plate-like member can be formed by bending the planarly formed convex portion so as to partially extend the outer peripheral portion of the plate-like member by 90 ° (SUS (SUS It can be manufactured by pressing a plate etc.).
Moreover, if there is no problem in strength and operation, only one convex portion and one concave portion may be formed.

Here, FIG. 19 is a view showing a state of the drive wire inside in a sliding contact (bending) state of the joint member.
As shown in the figure, on the lower end side of the outer peripheral portion of the tubular member 121, the inner surface of the tubular member 121 and the drive wire W1 interfere with each other. Such interference prevents the bending operation and causes a loss of drive wire pulling force.
In order to prevent this, as illustrated in FIG. 20, the diameter is wider than the diameter of the drive wire at the location on the inner side of bending due to the sliding contact of two adjacent joint members on the outer peripheral portion of the tubular member. The slit S2 may be formed. Interference between the side surface of the tubular member and the drive wire can be suppressed by the slit S2.

In the present embodiment, a projection AL is provided in which the plate-like member 122 is engaged with the convex portions P11 and P12 and the bending angle α due to sliding contact between two adjacent joint members is provided. As an example, the protrusion AL may not be provided.
For example, as illustrated in FIG. 21A, taking advantage of the fact that the convex portion P51 has a shape that spreads in an arc shape with respect to its root portion, the root portion of the convex portion P51 engages with the notch portion 1221 of the plate-like member 122. You may make it match. The restriction of the bending angle α of the joint member can be adjusted by the inclination angle β (see FIG. 7A) or the like of the base end surface TS on both sides of the concave portions C11 and C12.
In FIG. 21A, when the engagement force with the plate-like member 122 is insufficient, as shown in FIG. 21B, the engagement recess P61R may be provided in the root portion of the protrusion P61. The engagement recess P61R is similar to the engagement recess 132 provided in the tip member 13.

In this embodiment, although each joint member is provided with the plate-like member as an example, the present invention is not limited to this. The main function of the plate-like member is to prevent interference between each wire and another member (another wire or another joint member to be fitted) by passing a core wire controlling a drive wire or an end effector through the hole. In addition, it is possible to suppress deviation or deviation of the concave and convex portions of the two joint members 12 engaged with each other in the radial direction (direction along the bending axis). For example, when it is relatively difficult for interference between the respective members or radial displacement of the two joint members 12 to be relatively unlikely to occur due to sufficient rigidity of each wire, for example, plate members for every other joint member May be provided.

As in the present embodiment, when the bending through holes of the plate-like member are disposed so as to penetrate in parallel with the central axis of the tube of the tubular member when another joint member is connected in the vertical direction, the drive wire The friction of the bending through holes can be reduced, and the radial displacement between the concave and the convex of the two joint members 12 engaged can be reduced. As in the present embodiment, by forming the bending through holes in point symmetry in accordance with the angle formed by the recess and the protrusion, it is possible to make all the joint members stacked one on the other identical. A plate-like member may be prepared. Since the tubular member and the plate-like member are separate, it is possible to easily cope with the change of the plate-like member (by preparing a plurality of plate-like members in which the positions of the bending through holes are changed).

Second Embodiment
As Embodiment 2, a bending control method of a treatment tool by a motorized drive will be described.
The treatment tool in the present embodiment is the same as that in the first embodiment, so the description here will be simplified or omitted.

FIG. 22 is a front view showing an outline of the operation unit 3 and the motor drive 7 of the treatment tool.
The operation unit 3 of the treatment tool of the present embodiment is mechanically joined to the motor-driven drive 7 that can be operated electrically.
The dials 31 protruding from the operation unit 3 push and pull and rotate core wires passing through the drive wires passing through the bending through holes and the device through holes, and are driven by the electric drive 7.
By providing the dials 31 of the operation unit 3 and the pulleys 75 fitted with the dials 31 on the motor drive 7 side, the pulleys 75 of the motor drive unit 7 are rotated by the respective motors 74, It is what drives a dial.
The motor drive 7 is provided with an input unit 72 configured of, for example, a joystick, and receives an input of a bending direction instruction from the user. In the motor-driven drive 7, each motor 74 is driven according to an input from the user by a control method described below, and the bending portion is bent as instructed by the user. Not only electric operation but also manual operation (direct operation of the dial 31 of the operation unit 3) is possible.

FIG. 23 is a block diagram showing an outline of the configuration of the motor drive 7.
As shown in FIG. 23, the electric drive motor 7, an input unit 72, the motor ₇₄ U _{~ W} and, the motor ₇₄ U _~ a driver ₇₃ U _{~ W} for driving the _W, various arithmetic processes, each driver 73 _An arithmetic unit 71 etc. performing control of _U to _W , etc. are provided. Devices (a potentiometer, an encoder, etc.) for detecting a rotation position and rotation speed are provided in the rotating shaft of each motor, and feedback control (PID control etc.) by the detection result of the said device is performed.
In the calculation unit 71, when the target bending state is input from the input unit 72 as XY coordinates which are target positions based on the input bending instruction, the wire pulling amount is calculated based on the XY coordinates as described below. calculate. A wire bending amount obtained by this is converted into a corresponding motor pulley angle, and the desired bending control is performed by setting the pulley angle as a target angle of feedback control.

Next, the method of calculating the wire pulling amount will be described.
FIG. 24 is a diagram showing a conceptual flow of an algorithm of calculation of a traction amount of a drive wire in bending control of a treatment tool.
The calculation algorithm of the amount of pulling of the driving wire is a step of acquiring a target bending state as XY coordinates, and a vector represented by the XY coordinates in an n-dimensional (three-dimensional in this embodiment) multidimensional oblique coordinate system A step of vector decomposition into coordinate axis vectors along the coordinate axes, a step of calculating a joint bending angle about each basic bending axis by multiplying the obtained vector amount of each axis by a predetermined gain, and a joint about each basic bending axis Calculating the change amount of the path length of the drive wire corresponding to each basic bending axis based on the bending angle (processing on the lower side of the branch in FIG. 24), and each basic based on the joint bending angle around each basic bending axis Calculating the load applied to the drive wire corresponding to the bending axis, and calculating the amount of extension of the drive wire based on the load (processing on the upper side of the branch in FIG. 24); By adding the amount of elongation length variation and the drive wire, and a step of calculating a pulling amount of the drive wire.

FIG. 25 is an explanatory view of expressing a target position on a predetermined coordinate system for bending control of the bending portion 1 (acquiring a target bending state (a user's input to the input unit 72) as XY coordinates). is there.
Here, an example using an analog joystick as the input unit 72 is taken as an example, and an example in which the bending part 1 is bent according to the direction and the amount of tilting the stick is taken as an example. FIG. 25 models the state of the stick, that is, the state in which the stick is fallen due to user operation. That is, the user operates the stick of the input unit 72 in an attempt to bend the bending portion 1 in a desired direction, and the stick is inclined.
FIG. 25 is a model of a state in which the stick of the input unit 72 falls down, but it is also a model of a state in which the bending portion 1 is to be bent. This is because the bending portion 1 is bent according to the direction and the amount of the falling of the stick. That is, the XY plane in FIG. 25 corresponds to a plane substantially orthogonal to the axial direction of the treatment instrument at the proximal end of the bending portion.

First, as shown in FIG. 25, the direction and the amount in which the stick which is the bending instruction input from the user is turned down is acquired as the target coordinates (X ₀ , Y ₀ ).
In the present embodiment, the maximum bending angle is set in bending control. That is, the processing is to provide a fixed limiter for the input.
As shown in FIG. 26A and the following equation 1, when the magnitude of the input (corresponding to the magnitude of bending) based on the XY coordinates (X ₀ , Y ₀ ) is Mag and the limiter is Mag _Max , the input If Mag exceeds Mag _Max , a limiter is provided by replacing the input Mag with Mag _Max . Further, the input Mag, to which the limiter is applied as described above, is normalized using Mag _Max to perform processing of setting the size to a vector r with 0 or more and 1 or less (FIG. 26B). The normalization is performed for the convenience of the subsequent processing (calculation). Further, θ shown in FIG. 26A, FIG. 26B and the following equation 1 represents the vector r in polar coordinates.
The vector r on the XY coordinates obtained by the processing indicates the length of the stick falling amount (with a limiter), that is, the size of the angle to be bent, and θ is the direction of the stick falling, that is, the direction to bend Is an indicator of

Next, vector r is decomposed into coordinate axis vectors along the coordinate axes in a multi-dimensional oblique coordinate system having coordinate axes corresponding to the basic bending axes.
27A and 27B are explanatory diagrams of vector decomposition in the multidimensional oblique coordinate system. FIG. 27A shows the aforementioned XY coordinate system, and FIG. 27B shows a multidimensional oblique coordinate system.
The “multidimensional oblique coordinate system” is an n-dimensional coordinate system on the XY plane having a coordinate axis corresponding to the basic bending axis, and in the present embodiment, the basic bending axes mutually have a relative angle of 120 ° 3 Since this is the basic bending axis of the book, the coordinate system has three coordinate axes (U, V, W) having relative angles of 120 ° with each other on the XY plane.
As shown in FIG. 27B, the vector r is decomposed into coordinate axis vectors along the coordinate axes in the multidimensional oblique coordinate system. The vector decomposition closely approximates the target bending state with respect to n (three in this embodiment) rotation directions existing as basic bending axes. That is, the amount of rotation for obtaining good operability can be obtained.
Table 1 shows the relationship between θ of vector r and coordinate axis vectors (D _U , D _V , D _W ).

As described above, each coordinate axis vector D _U , D _V , D _W which is a decomposed vector has a value corresponding to an angle which needs to be inclined in each basic bending axis, and hence each coordinate axis vector D _U , D The joint bending angle T (deg) at each basic bending axis can be obtained by multiplying _{V 1} and D _W by a predetermined constant G (deg). The number 2 represents this.

In each basic bending axis, in order to obtain the joint bending angle T (deg), a tensile load corresponding to the joint bending angle is applied to the drive wire. Since the joint bending angle and the wire load are approximately proportional to each other, the wire load F (N) can be obtained by dividing the joint bending angle T (deg) by the coefficient H (deg / N). The number 3 represents this.

Since the amount of elongation of the drive wire due to the load is proportional to the load, the amount of elongation L (mm) of the drive wire due to the wire load F (N) is obtained by Equation 4 using a coefficient k (N / mm).

On the other hand, in order to obtain the joint bending angle T (deg) at each basic bending axis, the drive wire corresponding to each basic bending axis, that is, the driving wire located inside the bend with respect to the basic bending axis It is necessary to tow only a fixed amount. At the same time, it is necessary to feed a predetermined amount of drive wire located outside the bend with respect to the basic bending axis. FIG. 28 shows an explanatory view regarding the change in the path length of the drive wire (that is, the amount by which the drive wire is pulled or pulled out) in the bending of the bending portion.
As shown in the figure, for example, at a joint bending angle T (deg) of the basic bending axis BA1, a driving wire W1 (a driving wire positioned inside the bending with respect to the basic bending axis) corresponding to the basic bending axis BA1. The reduction of the path length is approximated and calculated as M × 2 × R tan (T / M / 2). At the same time, an increase in the path length of the drive wires W2 and W3 located outside the bending with respect to the basic bending axis BA1 is M × 2 × R / 2 × tan (T / M / 2). R corresponds to the distance from the basic bending axis BA1 to the drive wire W1, and M is the number of joints (= the number of joint members 12 + the base end members + the tip members-1 = the number of joint members 12 + 1). The number 5 represents this (increase / decrease P (mm) of the path length).

Here, if an approximation of tan α ≒ α is used, then equation 5 becomes equation 6.

The relationship between the extension amount L (mm) of the drive wire and the increase / decrease P (mm) of the path length obtained by the above and the wire pulling amount W (mm) required for this is shown in FIG. is there. That is,
Wire pulling amount W (mm) = elongation amount of drive wire L (mm) + increase / decrease of path length P (mm)
It is. Based on this, the wire pulling amount W (mm) is represented by the number 7.

That is, each drive is performed by performing calculation of Formula 7 based on the coordinate axis vector (D _U , D _V , D _W ) obtained by performing vector decomposition based on the target coordinates (X ₀ , Y ₀ ). The wire pulling amount W _U to W _W of the wire can be calculated.
In addition, the specific example of the setting value of the coefficient used by the said calculation was shown in Table 2. This is only an example, and each coefficient may be appropriately determined in accordance with the specification and the like of the specific device.

The calculation unit 71 calculates the wire pulling amounts W _U to W _W of each drive wire by the above calculation method, and converts the wire pulling amounts W _U to W _W into pulley angles (determined according to the specifications of the individual specific devices) Coefficient etc.). Then, by performing feedback control with the pulley angle as a target angle, bending control corresponding to the bending instruction input from the input unit 72 is performed.
Here, an analog joystick is taken as an example, and an example in which the input to the input unit 72 is treated as an instruction of the bending direction and the size thereof is taken as an example. . For example, when using digital input means such as a direction key, the target position may be handled only in the direction and the angle (bending size) to be bent in one control cycle may be operated as a constant value. That is, the process may be such that the angle to be bent is adjusted according to the time during which the direction key is input.
Further, for example, an input unit capable of detecting the speed of tilting the joystick may be used, and the angle to be bent in one control cycle may be changed according to the speed of tilting. The said process should just multiply the gain according to the speed down in several 2 grade | etc.,.

As described above, according to the bending control method of the present embodiment, even in the bending control of a non-orthogonal wire placement type treatment tool in which the control wires are arranged at an interval of 120 ° as in the first embodiment, reverse motion The bending operation can be performed with good operability by a simple calculation without requiring a complicated calculation using science.
In the present embodiment, an example in which the basic bending axes (and the corresponding control wires) have an interval of 120 ° (one in which the multidimensional oblique coordinate system has three dimensions) has been described as an example. The concept of calculating the amount of traction of each control wire based on vector decomposition into a two-dimensional oblique coordinate system can be applied to n-dimensional ones.

1. . . Bend
11. . . Proximal member 12. . . Joint member 121. . . Tubular member 122. . . Plate-shaped member H1. . . Device through holes H2. . . Bending through holes 1221. . . Notch S1. . . Slit P11, 12. . . Convex part C11, 12. . . Recess AL. . . Projection (bending angle limiting member)
BL. . . Flexure limiting member S2. . . Slit (slit that is wider than the diameter of the drive member)
BA1 to 3. . . Basic bending axis 13. . . Tip member 131. . . Notched section 132. . . Engaging recess 2. . . Sheath section 3. . . Operation unit 31. . . Dial 5. . . Electrode scalpel (end effector)
7. . . Electric drive 71. . . Operation unit 72. . . Input section 73 _U to _W. . . Drivers 74 _U to _W. . . Motor 75. . . Pulley CW. . . Electrode wire (core wire)
8. . . SUS tube PT. . . Polymer tube T. . . Treatment tools W1 to 3. . . Drive wire (drive member)

Claims (21)

1. A joint member which is disposed coaxially in parallel with each other to constitute a bendable treatment tool,
   A tubular member,
   A plate-like member disposed across the inside of the tubular member with respect to the tubular member, the bending through hole axially penetrating the plate-like member, and the plate-like member being the shaft A plate member provided with a device through hole penetrating in a direction;
   A recess formed on one axial end of the joint member;
   A convex portion formed on the other end side in the axial direction of the joint member, the convex portion being in sliding contact with the concave portion formed in the adjacent joint member;
   Joint member provided with
2. A pair of the concave portions are formed on one end side in the axial direction of the joint member so as to face in the radial direction of the joint member,
   The joint member according to claim 1, wherein a pair of the convex portions are formed on the other axial end side of the joint member so as to face in the radial direction of the joint member.
3. The joint member according to claim 2, wherein a line connecting the pair of concave portions and a line connecting the pair of convex portions are substantially parallel.
4. The joint member according to claim 2, wherein a relative angle between a line connecting the pair of concave portions and a line connecting the pair of convex portions is approximately 90 °.
5. The joint member according to claim 2, wherein a relative angle between a line connecting the pair of concave portions and a line connecting the pair of convex portions is approximately 120 °.
6. The joint member according to claim 5, further comprising a bending restriction member that restricts bending due to sliding contact between two joint members adjacent to each other to bending to one side.
7. The pair of plate-like members is configured as a pair of the protrusions are configured as a part of the outer periphery of the tubular member, and the plate-like member further includes a notch that engages with the pair of the protrusions. The joint member according to claim 2 engaged with the convex portion of
8. The joint member according to claim 7, wherein the plate-like member further includes a slit extending from the notch portion to the bending through hole or the device through hole.
9. The slit which becomes wider than the diameter of a drive member is further formed in the part used as the bending inner side of the bending by two joint members which adjoin each other in the perimeter of the above-mentioned tubular member by sliding contact. Joint member.
10. The recess and the protrusion are formed on one end side in the axial direction of the joint member so as to face in the radial direction of the joint member,
    The joint member according to claim 1, wherein the convex portion and the concave portion are formed on the other end side in the axial direction of the joint member so as to face in the radial direction of the joint member.
11. The joint member according to claim 10, wherein a line connecting the concave portion and the convex portion on one end side in the axial direction of the joint member and a line connecting the concave portion and the convex portion on the other end side are substantially parallel.
12. The relative angle between the line connecting the concave portion and the convex portion on one end side in the axial direction of the joint member and the line connecting the concave portion and the convex portion on the other end side is approximately 90 °. Joint member.
13. The relative angle between the line connecting the concave portion and the convex portion on one end side in the axial direction of the joint member and the line connecting the concave portion and the convex portion on the other end side is approximately 120 °. Joint member.
14. The joint member according to claim 1, further comprising a bending angle limiting member that limits an angle of bending due to sliding contact between two joint members adjacent to each other to less than 30 °.
15. The bending angle limiting member is a protrusion formed on the convex portion, the tubular member, or the plate-like member, and the protrusion abuts with an adjacent joint member as the treatment tool is bent, and the adjacent members mutually adjoin each other. The joint member according to claim 14, wherein the angle of bending of the two joint members is limited to less than 30 °.
16. The joint member according to claim 1, wherein the recess and the protrusion are integrally formed as a part of an outer peripheral portion of the tubular member.
17. A treatment tool formed by mutually assembling a plurality of joint members according to claim 1.
18. A plurality of tubular members having a recess formed on one end side in the axial direction and a protrusion formed on the other end, wherein the recess of one tubular member of the tubular members adjacent to each other is the protrusion of the other tubular member A plurality of tubular members configured to be bendable by sliding contact with the
    A plate-like member having a through hole for bending in the axial direction of the tubular member and a device through hole for passing in the axial direction of the tubular member, wherein at least one of the tubular members is a tubular member And a plate-like member disposed across the inside of the member.
19. 19. The treatment tool according to claim 18, wherein a plurality of bending through holes are formed in the plate-like member, and a plurality of driving members are respectively inserted into the plurality of bending through holes. A bending control method of a treatment tool having a basic bending axis and provided with the drive member corresponding to each of the basic bending axes,
    A target based on an input bending instruction in a multidimensional oblique coordinate system having a coordinate axis corresponding to the basic bending axis on a plane substantially orthogonal to the axial direction of the treatment tool at the proximal end of the bending portion of the treatment tool Decomposing the position into a coordinate axis vector along the coordinate axis;
    Calculating the amount of pulling of the drive member corresponding to the basic bending axis corresponding to each coordinate axis based on the coordinate axis vector;
    And a bending control method of a treatment tool.
20. The plurality of basic bending axes are three basic bending axes mutually having a relative angle of 120 °, and the multidimensional oblique coordinate system is represented by three coordinate axes mutually having a relative angle of 120 °. The bending control method of a treatment tool according to claim 19, which is an oblique coordinate system.
21. In the calculation of the pulling amount,
    Calculating the amount of change in the path length of the drive member before and after bending of the treatment tool;
    Calculating an amount of extension of the drive member due to a load applied to the drive member when the treatment tool is bent;
    Calculating the amount of pulling based on the amount of change in the path length and the amount of elongation of the drive member;
    The bending control method of the treatment tool according to claim 19, comprising:

Images