Ligation device

Abstract

To provide a ligation device, when ligating a ligation object body, capable of easily forming two thread loops required to form a knot of a thread for ligating the ligation object body.SOLUTION: A pair of first thread loop shaft 92 and second thread loop shaft 94 respectively include a pair of vertical walls 114 and 116 and a pair of vertical walls 132 and 134, and radial thread grooves 118a and 118b and radial thread grooves 136a and 136b respectively formed on the top parts of the pair of vertical walls 114 and 116 and the pair of vertical walls 132 and 134. A thread T pulled into the radial thread grooves 118a, 118b and 136a, 136b by a repositioning thread hook 54 is wound around each of the outer peripheral surfaces of the pair of vertical walls 114, 116 and 132, 134, so that two thread loops L1 and L2 are formed by a thread T2 on a proximal side. The thread T1 located on a distal side is made to pass through the thread loop L1 and L2 formed by the thread T2 on the proximal side to form a knot M.SELECTED DRAWING: Figure 15

Description

Technical Field

[0005] , ,

[0001] The present invention relates to a ligation device capable of ligating a ligated object using a thread, and particularly to a ligation device capable of stably forming a thread loop for forming a knot in a part of the thread prior to ligation.

Background Art

[0002] When ligating a ligated object using a thread in the field of surgery of a living body or the like, a suturing device has been proposed that can suture the ligated object using a thread-like member wound around the ligated object without using a metal staple. For example, the suturing devices proposed in Patent Document 1 and Patent Document 2 are such.

[0003] The suturing device proposed in Patent Document 1 is such that a suture strip formed in a U shape in advance is attached for each single fastening operation, and the ligated object is ligated using the attached suture strip. According to the suturing device proposed in this Patent Document 1, the suture strip has to be attached to the suturing device for each single fastening operation, and ligation using a thread was difficult.

[0004] Patent Document ② describes a medical device in which a proximal shaft, a flexible bending part, and a distal shaft are connected, and a flexible bending part through which a wire is passed is provided, and a tip part is connected to a part more distal than the bending part or to the distal part of the bending part, and the bending part is bent by pulling an operation wire at the proximal end part so that the wire can surround a ligated object such as a blood vessel. According to the medical device of this Patent Document 2, the wire can be replaced with a suture surrounding the ligated object by pulling out the wire from the proximal end with a suture connected to the tip of the wire, and the ligated object can be ligated by sending a knot created outside the living body into the living body through the suture.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

[0006] However, neither Patent Document 1 nor Patent Document 2 discloses any technique for easily forming the two thread loops necessary for knot formation when ligating an object to be ligated using thread.

[0007] The present invention was made against the above circumstances, and its objective is to provide a ligating device that can easily form the two thread loops necessary for forming a knot in the thread used to ligate an object to be ligated. [Means for solving the problem]

[0008] The gist of the ligation device of the present invention is a ligation device comprising: (a) a columnar body; a holding part connected to one end of the body in the longitudinal direction for holding an object to be ligated; a thread pulling member provided within the body so as to be movable along the longitudinal direction for pulling a thread to ligate the object to be ligated into the body; and a thread loop forming part for forming two thread loops in the thread pulled into the body by the thread pulling member, wherein (b) the thread loop forming part has a pair of thread loop axes that rotate in opposite directions around mutually parallel rotation axes that intersect the movement trajectory of the thread pulling member, and (c) Each of the pair of thread loop axes comprises: (d) a main body provided at a position spaced apart from the movement trajectory and rotating about the rotation axis; (e) a pair of vertical walls projecting from the main body in the direction of the rotation axis, which move between a position overlapping the movement trajectory and a position spaced apart from the movement trajectory as the main body rotates; and (f) thread grooves formed at the top of each of the pair of vertical walls, which engage with the thread pulled in by the pull-in member. [Effects of the Invention]

[0009] According to the ligating device of the present invention, a pair of thread loop axes that rotate in opposite directions around parallel rotation axes have a pair of vertical walls that move between a position overlapping the movement trajectory and a position separated from the movement trajectory as the main body rotates, and thread grooves formed at the top of each of the pair of vertical walls that engage with the thread pulled in by the pull-in member. When the pair of thread loop axes rotate in opposite directions around parallel rotation axes, the thread pulled in by the pull-in member into the thread groove is wrapped around the outer circumferential surface of the pair of vertical walls, forming two thread loops. Within these two thread loops, the pull-in member moves distally through the two thread loops to grasp the thread located distal to the object to be ligated, and the pull-in member moves proximal to the object to be ligated, thereby passing the thread and forming a knot. [Brief explanation of the drawing]

[0010] [Figure 1] This is a perspective view from diagonally above showing a ligation device according to one embodiment of the present invention. [Figure 2] Figure 1 is a plan view of the ligation device. [Figure 3] Figure 1 is a side view of the ligation device. [Figure 4] This is a rear view showing the proximal end face of the ligation device in Figure 1. [Figure 5] Figure 1 is a longitudinal cross-sectional view of the ligation device, which is equivalent to the IV-IV cross-sectional view of the ligation device in Figure 2. [Figure 6] Figure 1 is a horizontal cross-sectional view of the ligation device, which is equivalent to the VV cross-sectional view of the ligation device in Figure 3. [Figure 7] Figure 1 is a perspective view showing the ligation thread hook used in the ligation device. [Figure 8] Figure 7 is a plan view showing the tip of the ligation thread hook. [Figure 9] Figure 7 is a magnified perspective view of the tip of the ligation thread hook. [Figure 10] This is a plan view showing the tip of the repositioning thread hook used in the ligation device shown in Figure 1. [Figure 11]It is a cross-sectional view for explaining the cross-section of the thread hook for rearrangement in FIG. 10. [Figure 12] It is a perspective view showing the thread feed rod used in the ligation device of FIG. 1. [Figure 13] It is a view for explaining the positional relationship between the thread feed rod in FIG. 12 and the tip of the ligation thread hook in FIG. 8. [Figure 14] It is a view for explaining the positional relationship between the thread feed rod in FIG. 12 and the tip of the rearrangement thread hook in FIG. 10. [Figure 15] It is a perspective view for explaining the pair of thread loop shafts provided in the ligation device of FIG. 1. [Figure 16] It is a view for explaining the ligated object gripping step of gripping the ligated object between the lower jaw part and the upper jaw part among the operations of the ligation device of FIG. 1. [Figure 17] It is a view for explaining the knot pusher forward movement step of moving the knot pusher and the ligation thread hook forward toward the ligated object among the thread gripping operations of the ligation device of FIG. 1. [Figure 18] It is a view for explaining the ligation thread hook protruding step of protruding the ligation thread hook that grips the thread on the distal side of the ligated object from the knot pusher among the thread gripping operations of the ligation device of FIG. 1. [Figure 19] It is a view for explaining the thread feed rod protruding step of raising the thread feed rod until it protrudes from the upper jaw part among the thread gripping operations of the ligation device of FIG. 1. [Figure 20] It is a view for explaining the thread gripping step of protruding the thread hook gripping member from the cylindrical body of the ligation thread hook to semi-grip the thread on the distal side of the ligated object and then slightly retracting the thread hook gripping member among the thread gripping operations of the ligation device of FIG. 1. [Figure 21] It is a view for explaining the knot pusher retraction step of lowering the thread feed rod and retracting the knot pusher and the ligation thread hook among the thread gripping operations of the ligation device of FIG. 1. [Figure 22] It is a view for explaining the first thread cutting step of completely gripping the thread at the thread hook gripping member and then raising the thread feed rod until it protrudes from the upper jaw part to cut the thread among the thread cutting operations of the ligation device of FIG. 1. [Figure 23]This is a diagram for explaining a thread insertion process in the thread cutting operation of the ligation device in FIG. 1. In this process, the thread is semi-held by the thread hook holding member, and then the ligation thread hook and the knot pusher are retracted to the proximal end of the ligation device, thereby inserting the thread through two thread loops. [Figure 24] This is a diagram for explaining a thread loop removal process in the ligation operation of the ligation device in FIG. 1. In this process, while applying tension to the thread by advancing the ligation thread hook and retracting the rearrangement thread hook, the pair of thread loop axes are rotated counterclockwise to remove the thread loops wound around the pair of thread loops. [Figure 25] This is a diagram for explaining a thread loop movement process in the ligation operation of the ligation device in FIG. 1. In this process, while advancing the knot pusher and the ligation thread hook toward the ligated object and retracting the rearrangement thread hook, the two thread loops are moved forward while tightening the thread loops. [Figure 26] This is a diagram for explaining a knot formation process in the ligation operation of the ligation device in FIG. 1. In this process, the rearrangement thread hook is advanced and the ligation thread hook is retracted to convert the loop closer to the knot pusher to form a knot. [Figure 27] This is a diagram showing an enlarged view of the thread loops before the knot formation process in FIG. 26. [Figure 28] This is a diagram showing an enlarged view of the state where the thread loop closer to the knot pusher among the two thread loops is converted after the knot formation process in FIG. 26. [Figure 29] This is a diagram for explaining a second thread cutting process in the ligation operation of the ligation device in FIG. 1. In this process, with the knot pusher retracted, the second cutter is rotated to the cutting position to simultaneously cut the two threads between the knot and the ligation thread hook and the rearrangement thread hook. [Figure 30] This is a diagram for explaining a thread recovery process in the ligation operation of the ligation device in FIG. 1. In this process, the second cutter is retracted from the cutting position, and the knot pusher and the ligation thread hook are retracted to the rear end to recover the thread. [Figure 31] This is a diagram for explaining a ligated object removal process in the ligation operation of the ligation device in FIG. 1. In this process, by opening and closing the upper jaw, the ligated object after ligation is removed. [Figure 32] This figure illustrates the repositioning thread hook advancement process in the repositioning operation of the ligating device shown in Figure 1, in which the repositioning thread hook is advanced to the tip of the ligating device. [Figure 33] This figure illustrates the thread feeding rod protrusion step in the thread gripping operation of the ligation device shown in Figure 1, specifically the step where the thread feeding rod is raised until it protrudes from the upper jaw portion. [Figure 34] This figure illustrates the thread gripping process in the repositioning operation of the ligating device shown in Figure 1, in which the thread hook gripping member is extended from the cylindrical body of the repositioning thread hook to fully grip the thread that has been raised by the thread feed rod, and the repositioning thread hook is slightly retracted. [Figure 35] This figure illustrates the thread placement process in the repositioning operation of the ligation device shown in Figure 1, in which the thread feeding rod is lowered and stored inside the mandible portion, the repositioning thread hook is moved backward toward the proximal end of the ligation device relative to the pair of thread loop axes, and the thread is placed in the rod guide groove that guides the repositioning thread hook of the pair of thread loop axes. [Figure 36] This diagram illustrates the thread placement process within the thread groove in the repositioning operation of the first ligating device, in which a pair of thread loop axes are rotated 90 degrees in the first rotational direction to position the thread in the rod guide groove into a thread groove perpendicular to the rod guide groove. [Figure 37] This diagram illustrates the thread loop formation process in which, during the rearrangement operation of the first ligating device, a pair of thread loop axes are rotated 270 degrees in a second rotation direction opposite to the first rotation direction, thereby winding thread around the pair of thread loop axes to form two thread loops. [Figure 38] This diagram illustrates the thread hook positioning process in the rearrangement operation of the first ligating device, in which the knot pusher is rotated around its axis while advancing, passing under the threads of two thread loops, each wrapped around a pair of thread loop axes. [Figure 39] Figure 38 shows the state in which the knot pusher approaches the circumferential thread of the thread loop on the base end during the thread hook placement process. [Figure 40]Figure 38 shows the state in the thread hook placement process where the knot pusher moves forward and rotates around its axis, causing the inclined surface formed at its tip to attempt to pass over the circumferential thread of the thread loop on the base end side. [Figure 41] Figure 38 shows the thread hook placement process, where the knot pusher moves forward and rotates around its axis, causing the inclined surface formed at its tip to attempt to pass under the radial thread of the thread loop at the base end. [Figure 42] Figure 38 shows the thread hook placement process, where the knot pusher moves forward and rotates around its axis, causing the inclined surface formed at its tip to attempt to pass over the circumferential threads of the base end thread loop and the circumferential threads of the tip end thread loop. [Figure 43] Figure 38 shows the thread hook placement process, where the knot pusher moves forward and rotates around its axis, causing the inclined surface formed at its tip to attempt to pass under the radial thread of the thread loop at the tip. [Figure 44] Figure 38 shows the thread hook placement process, where the knot pusher moves forward and rotates around its axis, causing the inclined surface formed at its tip to attempt to pass over the circumferential thread of the thread loop at the tip. [Modes for carrying out the invention]

[0011] Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. [Examples]

[0012] (Configuration of the ligation device 10) Figures 1, 2, 3, and 4 show a perspective view, plan view, side view, and rear view (i.e., the posterior end surface) of a ligation device 10 according to one embodiment of the present invention, with the second jaw portion 18 in a closed state. Figure 5 is a cross-sectional view taken along line IV-IV of Figure 2. Figure 6 is a cross-sectional view taken along line VV of Figure 3.

[0013] The ligation device 10 is longitudinal in shape as a whole, and its tip opens and closes between a separated position and a holding position, thereby enabling it to form a knot M (see Figure 28) in the thread T wrapped around a part of a living body, such as a blood vessel, in the holding position. The ligation device 10 is also a fastening device that tightens the part to be ligated 32 using the thread T. In this embodiment, as shown in Figure 1, the longitudinal direction of the ligation device 10 is defined as the x-direction, the first short direction, i.e., the up and down direction, which is perpendicular to the x-direction and parallel to the opening surface of the tip of the ligation device 10 is defined as the z-direction, and the second short direction, i.e., the width direction, which is perpendicular to the x-direction and z-direction is defined as the y-direction.

[0014] The ligation device 10 comprises a columnar body 14, a holding part, and a thread pulling member. The holding part is connected to one end of the body 14 in the x-direction and holds the body to be ligated 32. The holding part includes a first jaw portion 12 and a second jaw portion 18. The first jaw portion 12 is connected to one end of the body 14 in the x-direction. The second jaw portion 18 moves between a holding position that holds the body to be ligated 32 between itself and the first jaw portion 12 and a separated position that is separated from the first jaw portion 12. In this embodiment, in the z-direction, i.e., the vertical direction, the first jaw portion 12 is positioned below the second jaw portion 18. Details of the first jaw portion 12 and the second jaw portion 18 will be described later. In the following, the first jaw portion 12 may also be referred to as the mandible portion 12, and the second jaw portion 18 as the maxillary portion 18. The thread-pulling member is provided so as to be movable along the x-direction within the main body 14 and pulls the thread used to ligate the object to be ligated 32 into the main body 14. The thread-pulling member is either a first thread-pulling member or a second thread-pulling member, which will be described later. The ligating device 10 further includes a thread-feeding rod 64. The thread-feeding rod 64 is housed within the first jaw portion 12. The thread-feeding rod 64 has a thread-engaging portion 74 at its tip that engages with the thread T used to ligate the object to be ligated 32. The thread-feeding rod 64 moves between a retracted position where the thread-engaging portion 74 is located within the first jaw portion 12 and a protruding position where the thread-engaging portion 74 protrudes from the first jaw portion 12 when the second jaw portion 18 is in a holding position. Details of the thread-feeding rod 64 will be described later. The ligating device 10 further includes a thread-loop forming portion 90. The thread loop forming section 90 forms two thread loops on the thread T that has been pulled into the main body 14 by the thread pulling member. Details of the thread loop forming section will be described later.

[0015] The ligation device 10 includes a swivel section 30, which is a connecting member that connects the first jaw section 12 and the second jaw section 18 to the main body 14. More specifically, the first jaw section 12 is integrally provided on the lower side of the tip of the swivel section 30. The second jaw section 18 has a pair of base ends 18a spaced apart in the y direction. The pair of base ends 18a are connected to the tip of the swivel section 30 by a pair of first pins 16 so that they can rotate around a first rotation axis C1 parallel to the y direction. As a result, the second jaw section 18 is movable between a holding position that holds the body to be ligated between it and the first jaw section 12 and a spaced position that is spaced apart from the first jaw section. The main body 14 includes a lower main body section 20, a middle main body section 22, and an upper main body section 24 that are stacked in the z direction, and a cylindrical fixing cylinder 26 into which they are fitted and fixed. The base end of the swivel section 30 is rotatably connected via a second pin 28 to a connecting plate 22a protruding from the tip of the middle main body section 22, so as to be around a second rotation axis C2 parallel to the z direction. As a result, the first jaw section 12 and the second jaw section 18 can be opened and closed, and since the first jaw section 12 and the second jaw section 18 are swivelably connected to the main body 14, the degree of freedom in operating the first jaw section 12 and the second jaw section 18 is increased.

[0016] The swivel section 30 is operated by a pair of swivel operating wires 33, one end of which is fixed to the swivel section 30, which are drawn out through a pair of swivel operating wire insertion holes 40 that open between the middle body section 22 and the upper body section 24 at the base end face of the ligation device 10 shown in Figure 4. The second jaw section 18 is operated by opening and closing a pair of opening and closing operating wires 23, one end of which is fixed to the second jaw section 18, which are drawn out through one of the pair of swivel operating wire insertion holes 40 and one of the pair of cutter operating wires 78a and 78b 78a at the base end face of the ligation device 10 shown in Figure 4.

[0017] The first jaw portion 12 is integrally projected from the swivel portion 30 toward the tip of the ligation device 10. The base end portion 12a of the first jaw portion 12 is formed parallel to the base end portion 18a of the second jaw portion 18 when the tip of the first jaw portion 12 and the tip of the second jaw portion 18 are in contact. Furthermore, the tip portion 12b of the first jaw portion 12 is inclined toward the tip portion 18b of the second jaw portion 18 as it approaches the tip in the longitudinal direction x. The first jaw portion 12 is formed in a curved shape as a whole. A predetermined gap D for accommodating the body to be ligated 32 is formed between the base end portion 12a of the first jaw portion 12 and the base end portion 18a of the second jaw portion 18.

[0018] As shown in Figures 5 and 6, a linear first thread hook insertion hole 38 is provided within the second jaw portion 18, along the longitudinal direction, i.e., the x-direction, of the ligating device 10, to selectively guide the ligating thread hook 34, which functions as a first thread pull-in member, and the repositioning thread hook 54, which functions as a second thread pull-in member, to the tip of the ligating device 10. The second jaw portion 18 has a thread feed rod insertion hole 42 formed through the second jaw portion 12, through which the thread feed rod 64 is inserted along the first short direction, i.e., the z-direction, which is perpendicular to the direction from the first jaw portion 12 to the second jaw portion 18, i.e., the x-direction, which is the longitudinal direction of the ligating device 10. The cross-sectional areas of the first thread hook insertion hole 38 and the thread feed rod insertion hole 42 intersect in some areas.

[0019] Furthermore, a first cutter 36 is fixed in the second jaw portion 18 at a position between the thread feed rod insertion hole 42 and the main body 14. This cutter cuts the thread T when the thread T, which is hooked onto the thread engagement portion 74 of the thread feed rod 64, is lifted in the z direction by the thread feed rod 64. As a result, when the second jaw portion 18 is in the holding position, the thread feed rod 64 protrudes further in the z direction from the first protruding position shown in Figure 19, where it slightly protrudes from the thread feed rod insertion hole 42 to grip the thread T onto the ligation thread hook 34, to the second protruding position shown in Figure 22. When the thread T hooked onto the thread engagement portion 74 of the thread feed rod 64 is lifted in the z direction, the thread T is cut by the first cutter 36 without moving the first cutter 36.

[0020] Figure 7 is a perspective view showing the ligation thread hook 34, Figure 8 is a plan view showing the tip of the ligation thread hook 34, and Figure 9 is a magnified perspective view showing the tip of the ligation thread hook 34. The ligation thread hook 34 has a cylindrical body 46 with a notch 44 formed at its tip that constitutes a thread hook portion for hooking the thread T, and a cylindrical thread hook gripping member 48 that is slidably inserted into the cylindrical body 46 and grips the thread T between itself and the notch 44. The whole is made of a material such as metal or plastic that can be bent and deformed. The thread T hooked on the notch 44 is gripped by the thread hook gripping member 48.

[0021] The cylindrical body 46 has a notch 44 in which the notch becomes shallower in the y-direction when viewed from the outside in the radial direction as it approaches the tip of the cylindrical body 46 in the x-direction, and has a hook projection 46a that protrudes linearly away from the tip of the cylindrical body 46 near the opening. The tip portion of the notch 44 has an inclined surface 46c that forms an acute angle with respect to the x-direction. The tip of the thread hook gripping member 48 has an inclined surface 48a that forms an acute angle with respect to the x-direction as it approaches the tip on the side where the notch 44 is shallower. The inclined surface 48a is opposite to the inclined surface 46c of the cylindrical body 46 and is parallel to that inclined surface 46c. This ensures that the thread T is securely gripped.

[0022] The tip of the cylindrical body 46 is provided with a flattened portion 46b having a thickness smaller than the inner diameter of the cylindrical body 46. On the portion of the flattened portion 46b facing the inclined surface 48a of the thread hook gripping member 48, an inclined surface 46c is formed parallel to the inclined surface 48a so as to be able to make surface contact with the inclined surface 48a of the thread hook gripping member 48. As a result, the inclined surface 46c parallel to the inclined surface 48a makes surface contact with the inclined surface 48a of the thread hook gripping member 48, thereby suppressing rotation of the thread hook gripping member 48 around its axis relative to the cylindrical body 46, and ensuring that the thread T is securely gripped between the inclined surface 48a of the thread hook gripping member 48 and the inclined surface 46c of the flattened portion 46b. Furthermore, since the flattened portion 46b has a thickness smaller than the inner diameter of the cylindrical body 46, the thread T gripped between the inclined surface 48a of the thread hook gripping member 48 and the inclined surface 46c of the flattened portion 46b can be pulled into the cylindrical body 46 and into the knot pusher 50.

[0023] The ligating thread hook 34 includes a cylindrical knot pusher 50 into which a cylindrical body 46 is slidably inserted, and into which the cylindrical body 46 is fitted in a slidable and protruding manner. The knot pusher 50 is mounted concentrically with the cylindrical body 46 and functions as the outer cylindrical member of the ligating thread hook 34. The tip of the knot pusher 50 is provided with an inclined end surface 50a into which the cylindrical body 46 protrudes.

[0024] Figure 10 is a plan view showing the tip of the repositioning thread hook 54 corresponding to the second thread pull-in member, and Figure 11 is a cross-sectional view showing the tip of the repositioning thread hook 54. The repositioning thread hook 54 has a cylindrical body 58 with a notch 56 formed therein that constitutes a thread hook portion for catching the thread T, and a cylindrical thread hook gripping member 60 that is slidably inserted into the cylindrical body 58 and grips the thread T between itself and the notch 56, and is made of a material such as metal or plastic that can be bent and deformed as a whole. The movement trajectories of the ligating thread hook 34 and the repositioning thread hook 54 are coaxial within the first thread hook insertion hole 38, the second thread hook insertion hole 80, and the third thread hook insertion hole 84. At the point where the fifth rotation axis C5 and the sixth rotation axis C6, which are the rotation centers of the first thread loop axis 92 and the second thread loop axis 94 described later, intersecting in series in the third thread hook insertion hole 84, the movement trajectory of the ligating thread hook 34 and the movement trajectory of the repositioning thread hook 54 are coaxial.

[0025] The tip portion 56a of the notch 56 formed in the cylindrical body 58 is formed such that the notch becomes deeper in the y-direction when viewed from the radially outside as it approaches the tip of the cylindrical body 46 in the x-direction. Furthermore, the tip of the thread hook gripping member 60 is inclined so as to approach the tip on the side where the notch 56 is shallower, and has an inclined surface 60a that forms an acute angle with respect to the x-direction. The inclined surface 60a is inclined in the opposite direction to the tip portion 56a of the notch 56.

[0026] At the tip end of the cylindrical body 58, on the side of the notch 56, a contact surface 58b parallel to the inclined surface 60a is formed in the portion facing the inclined surface 60a of the thread hook gripping member 60 so as to be able to make surface contact with the inclined surface 60a of the thread hook gripping member 60.

[0027] Within the base end 12a of the first jaw portion 12, a bobbin 62 on which thread T is wound is supported so as to be rotatable around a third rotation axis C3 parallel to the y direction, which is the second short direction. The bobbin 62 functions as a thread storage section and is positioned between a pair of pivot shafts 16 in the y direction and between the thread engagement portion 74 of the thread feed rod 64 and the main body 14 in the x direction, which is the longitudinal direction of the knotting device 10. In addition, a thread feed rod housing hole 66 for slidably housing the thread feed rod 64 is formed within the first jaw portion 12 along the longitudinal shape of the first jaw portion 12. Furthermore, in the first jaw portion 12, a hooking pin 67 for securing the thread T is provided on the tip side of the opening of the thread feed rod housing hole 66 of the first jaw portion 12.

[0028] Figure 12 is a perspective view showing the thread feed rod 64, a cylindrical connecting member 70 connected to the thread feed rod operating wire 68 shown in Figure 5, and a flexible connecting member 72 connecting the thread feed rod 64 and the connecting member 70. The connecting member 72 is made of a flexible material such as synthetic resin or a coil spring. The thread feed rod 64 and the connecting member 70 are offset so that the center of the thread feed rod 64 is shifted in the y-direction from the center of the first thread hook insertion hole 38 within the thread feed rod housing hole 66. The thread feed rod operating wire 68 is operated from the end exposed from the opening on the base end face of the knotting device 10 shown in Figure 4. When the end of the thread feed rod operating wire 68 is retracted, the thread feed rod 64 is in a retracted position where it is housed within the thread feed rod housing hole 66, and when the end of the thread feed rod operating wire 68 is extended, the thread engagement portion 74 of the thread feed rod 64 is in an extended position where it protrudes from the thread feed rod housing hole 66.

[0029] The thread feed rod 64 is formed in a curved shape that curves toward the z-direction, which is the first short direction, as it approaches its tip. At the tip of the thread feed rod 64, a groove-shaped thread engagement portion 74 for fitting the thread T is formed along the x-direction, which is the longitudinal direction of the tying device 10. Furthermore, when the tip of the thread feed rod 64 protrudes from the thread feed rod housing hole 66 and is positioned within the thread feed rod insertion hole 42 formed in the second jaw portion 18, a groove 76 is formed on the side surface of the tip of the thread feed rod 64, penetrating in the x-direction, to avoid interference with the tying thread hook 34 and the repositioning thread hook 54 inserted into the straight first thread hook insertion hole 38 formed in the x-direction within the second jaw portion 18. This makes it easier for the thread T to be hooked into the thread engagement portion 74.

[0030] The groove 76 is formed on the thread feed rod 64 upstream of the thread engagement portion 74, i.e., on the first jaw portion 12 side, in the first short direction, the z direction, and overlaps with the thread engagement portion 74. Furthermore, when the thread feed rod 64 is in the protruding position, the groove 76 is formed in the first short direction, the z direction, and overlaps with the first thread hook insertion hole 38. This allows the thread engagement portion 74 of the thread feed rod 64 to intersect with the notch (thread hook portion) 44 of the ligating thread hook 34 or the notch (thread hook portion) 56 of the repositioning thread hook 54 in the second short direction, the y direction.

[0031] Figure 13 shows the relationship between the ligating thread hook 34 and the thread feed rod 64 when the ligating thread hook 34 is advanced as far as the tip of the ligating device 10, the tip portion of the notch 44 that functions as the thread hook part of the ligating thread hook 34 is located on the longitudinal tip side of the second jaw portion 18 beyond the intersection of the first thread hook insertion hole 38 and the thread feed rod insertion hole 42, and the thread feed rod 64 is in its protruding position, which is the furthest outward from the thread feed rod insertion hole 42 in the z direction. In the protruding position of the thread feed rod 64, the thread engaging portion 74 formed at the tip of the thread feed rod 64 is located above the first thread hook insertion hole 38 in the z direction, i.e., downstream, in the first short direction, the z direction, and is in a position that overlaps with the first thread hook insertion hole 38 in the second short direction, the y direction. Furthermore, the groove 76 of the thread feed rod 64 is positioned to overlap with the first thread hook insertion hole 38 in the z and y directions. That is, the thread feed rod 64 has a groove 76 located below the thread engagement portion 74 in the z direction and overlapping with the thread engagement portion 74 in the y direction, and when the thread feed rod 64 is in its protruding position, the groove 76 overlaps with the first thread hook insertion hole 38 in the z direction. As a result, the thread engagement portion 74 of the thread feed rod 64 and the notch 44 that constitutes the thread hook portion of the tying thread hook 34 can intersect, and the thread T that engages with the thread engagement portion 74 formed at the tip of the thread feed rod 64 is hooked onto the notch 44 that functions as the thread hook portion of the tying thread hook 34.

[0032] In Figure 13, the first thread hook insertion hole 38 has a V-shaped tip bottom surface 38a consisting of a pair of inclined surfaces that move from the center toward the tip in a plan view in the xy plane. Similarly, the tip of the flattened portion 46b has a V-shaped tip surface 46d consisting of a pair of inclined surfaces that move from the center toward the tip in a plan view in the xy plane. As a result, the ligating thread hook 34 is advanced to the very tip, and the tip surface 46d formed at the tip of the flattened portion 46 comes into contact with the tip bottom surface 38a of the first thread hook insertion hole 38, thereby aligning the rotational phase of the cylindrical body 46 around its axis.

[0033] Figure 14 shows the relationship between the repositioning thread hook 54 and the thread feed rod 64 when the repositioning thread hook 54 is advanced as far as the tip of the ligating device 10, the tip portion of the notch 56 that functions as the thread hook part of the repositioning thread hook 54 is located on the longitudinal tip side of the second jaw portion 18 than the intersection of the first thread hook insertion hole 38 and the thread feed rod insertion hole 42, and the thread feed rod 64 is in its most protruding position in the z direction from the thread feed rod insertion hole 42. In this state, the thread engagement portion 74 formed at the tip of the thread feed rod 64 is located downstream of the thread feed rod insertion hole 42 in the z direction, i.e., separated from the first jaw portion 12 in the z direction, which is the first short direction, and is located in a position that overlaps with the first thread hook insertion hole 38 in the y direction, which is the second short direction. Also, the groove 76 of the thread feed rod 64 is located in a position that overlaps with the first thread hook insertion hole 38. As a result, the thread T that engages with the thread engagement portion 74 formed at the tip of the thread feed rod 64 is hooked onto the notch 56 which functions as the thread hook portion of the repositioning thread hook 54.

[0034] In Figure 14, the tip of the cylindrical body 58 has a V-shaped tip surface 58a formed on it, similar to the tip surface 46d of the cylindrical body 46, consisting of a pair of inclined surfaces that move from the center toward the tip in a plan view in the xy plane. This allows the repositioning thread hook 54 to be advanced to the very tip, and the tip surface 58a formed on the tip of the cylindrical body 58 to come into contact with the tip bottom surface 38a of the first thread hook insertion hole 38, thereby aligning the rotational phase of the repositioning thread hook 54 around its axis.

[0035] For example, as shown in Figures 5 and 6, the swivel section 30 of the main body 14 is provided with a second thread hook insertion hole 80 that is linearly connected to the first thread hook insertion hole 38 when the second jaw section 18 is closed, and a second cutter 82 for cutting the thread T in the second thread hook insertion hole 80. The second cutter 82 comprises a disc-shaped second cutter base 82a that is rotatably supported within the swivel section 30 around a fourth rotation axis C4 parallel to the z direction, and a second cutter blade 82b erected on the second cutter base 82a. The second cutter base 82a is rotated via a pair of cutter operating wires 78a and 78b fixed to the second cutter base 82a, which are pulled out through a pair of second cutter operating wire insertion holes 78 that open between the middle main body section 22 and the lower main body section 20 at the base end face of the ligation device 10 shown in Figure 4.

[0036] Within the fixing cylinder 26 of the main body 14, a third thread hook insertion hole 84 and a fourth thread hook insertion hole 86 are formed between the middle main body portion 22 and the upper main body portion 24, which are stacked on top of each other, and are linearly connected to the second thread hook insertion hole 80 when the swivel portion 30 is positioned on the center line of the main body 14. From between the third thread hook insertion hole 84 and the fourth thread hook insertion hole 86, a fifth thread hook insertion hole 88 branches off parallel to the fourth thread hook insertion hole 86 and is formed within the middle main body portion 22. The fourth thread hook insertion hole 86 opens between the middle main body portion 22 and the upper main body portion 24 at the center of the y-direction of the base end face of the ligation device 10 shown in Figure 4. A ligation thread hook 34 is inserted exclusively through the fourth thread hook insertion hole 86. Furthermore, the fifth thread hook insertion hole 88 opens into the central body portion 22 at the center of the y-direction of the base end face of the ligating device 10 shown in Figure 4. The repositioning thread hook 54 is inserted exclusively through the fifth thread hook insertion hole 88.

[0037] The first thread hook insertion hole 38, the second thread hook insertion hole 80, and the third thread hook insertion hole 84 are alternately inserted into the fourth thread hook insertion hole 86, which is a ligating thread hook 34, and the fifth thread hook insertion hole 88, which is a repositioning thread hook 54.

[0038] The ligating thread hook 34 is moved between a forward position in the first thread hook insertion hole 38 and a retracted position in the fourth thread hook insertion hole 86. The repositioning thread hook 54 is moved between a forward position in the first thread hook insertion hole 38 and a retracted position in the fifth thread hook insertion hole 88. In the retracted position in the fifth thread hook insertion hole 88, the repositioning thread hook 54 is in a first position parallel to the ligating thread hook 34 in the fourth thread hook insertion hole 86 from the first thread hook insertion hole 38, and in the position in the first thread hook insertion hole 38, i.e., the forward position, it is in a second position coaxial with the ligating thread hook 34 in the fourth thread hook insertion hole 86. This makes it possible to reposition the thread T without increasing the size of the ligating device 10.

[0039] Inside the fixing cylinder 26 of the main body 14, a thread loop forming section 90 is provided to form two thread loops L1 and L2 on the thread T in the third thread hook insertion hole 84. The thread loop forming section 90 includes a first thread loop shaft 92 for forming the first thread loop L1 and a second thread loop shaft 94 for forming the second thread loop L2. The first thread loop shaft 92 and the second thread loop shaft 94 are housed in the inner main body section 22 of the main body 14 so as to be rotatable around a fifth rotation axis C5 and a sixth rotation axis C6, respectively, which intersect with the movement trajectory of the ligating thread hook 34 or repositioning thread hook 54 moving within the third thread hook insertion hole 84 and are parallel to the z direction, which is the first short direction.

[0040] Figure 15 is an enlarged perspective view showing the first thread loop shaft 92 and the second thread loop shaft 94. The first thread loop shaft 92 and the second thread loop shaft 94 have cylindrical body portions 96 and 98 at the ends away from the third thread hook insertion hole 84. The first thread loop shaft 92 and the second thread loop shaft 94 are equipped with gears 100 and 102 that mesh with each other on the outer circumference of the body portion 96 and the outer circumference of the body portion 98, respectively, and are rotated in opposite directions relative to each other.

[0041] A groove 106 is formed in the cylindrical body portion 96 of the first thread loop shaft 92, around which the thread loop shaft operating wire 104 is wound. The ends of the thread loop shaft operating wire 104 are led out from a pair of thread loop shaft operating wire insertion holes 108 and 110 that open at the center in the z direction and spaced apart in the y direction on the base end face of the ligation device 10 shown in Figure 4. By operating the pair of ends of the thread loop shaft operating wire 104 led out from the pair of thread loop shaft operating wire insertion holes 108 and 110, the first thread loop shaft 92 is rotated, and the second thread loop shaft 94 is rotated in the opposite direction by the same angle as the first thread loop shaft 92. In Figure 15, in a plan view, the counterclockwise rotation of the first thread loop shaft 92 and the clockwise rotation of the second thread loop shaft 94 are the second rotation direction R2, i.e., the loop-forming rotation direction, and the rotation opposite to these is the first rotation direction R1, i.e., the non-loop-forming rotation direction.

[0042] The main body portion 96 of the first thread loop shaft 92 has a pair of vertical walls 114 and 116 projecting in the first lateral direction, i.e., the z direction, with a rod guide groove 112 in between through which a ligating thread hook 34 or a repositioning thread hook 54 that moves within the third thread hook insertion hole 84 is inserted. The rod guide groove 112 guides the ligating thread hook 34 or the repositioning thread hook 54 and functions as part of the third thread hook insertion hole 84. The movement trajectories of the ligating thread hook 34 and the movement trajectories of the repositioning thread hook 54 are coaxial at the positions where they intersect with the fifth rotation axis C5 and the sixth rotation axis C6. The pair of vertical walls 114 and 116 are positioned in a rotational position that overlaps with the movement trajectory of the ligating thread hook 34 or the repositioning thread hook 54 as it moves within the third thread hook insertion hole 84 in conjunction with the rotation of the first thread loop axis 92, and in a rotational position that is separated from the movement restriction. As a result, the repositioning thread hook 54 retracts, positioning the thread T within the rod guide groove 112. The rotation of the first thread loop axis 92 and the second thread loop axis 94 forms the first thread loop L1 and the second thread loop L2 around them, and the ligating thread hook 34 advances through the rod guide groove 112, thereby forming an entanglement of thread T for forming a knot M.

[0043] At the tops of the pair of vertical walls 114 and 116, radial thread grooves 118a and 118b, which function as thread guide grooves, are formed in a direction that intersects, preferably perpendicular to, the rod guide groove 112 around the fifth rotation axis C5. The groove bottoms of the radial thread grooves 118a and 118b are raised by a predetermined height value h in the z direction compared to the groove bottom of the rod guide groove 112. The height value h is preferably set to be equal to the height from the groove bottom of the rod guide groove 102 to the center of the knot pusher 50, which is the outer cylindrical member of the ligating thread hook 34 located inside the rod guide groove 102.

[0044] Of the pairs of vertical wall portions 114a and 114b, 116a and 116b, each divided circumferentially by the radial thread grooves 118 of the pair of vertical walls 114 and 116, the pair of first vertical wall portions 114a and 116a located at the tip of the first rotation direction R1 of the first thread loop shaft 92 have first thread guide inclined surfaces 120a and 120b formed thereon, which move away from the bottom of the rod guide groove 112 in the z direction as the first thread loop shaft 92 moves toward the second rotation direction R2. The first thread guide inclined surfaces 120a and 120b move the thread T in the rod guide groove 112 toward the bottom of the rod guide groove 112 as the first thread loop shaft 92 rotates toward the first rotation direction R1, and guide it into the radial thread groove 118.

[0045] A pair of first vertical wall portions 114a and 116a located at the tip of the first rotation direction R1 of the first thread loop axis 92 have thread engagement angle portions 122a and 122b formed on them, which include a ridge line that is the intersection of the inner wall surface of the radial thread groove 118 and the outer circumferential surfaces of the first vertical wall portions 114a and 116a, and which form an acute angle slightly smaller than a right angle when viewed in the direction of the fifth rotation axis C5, i.e., the z direction. The tangents of the outer circumferential surfaces of the first vertical wall portions 114a and 116a passing through the ridge line are inclined as tangents at a position shifted by the width dimension of the radial thread groove 118 with respect to a line perpendicular to the longitudinal direction of the radial thread groove 118, so that the angle formed with the inner wall surface of the radial thread groove 118 is an acute angle slightly smaller than a right angle. The thread engagement angles 122a and 122b catch the thread T in the radial thread grooves 118a and 118b as the first thread loop axis 92 rotates in the second rotational direction R2, thereby forming the first thread loop L1 around the fifth rotational axis C5.

[0046] Of the pair of vertical wall sections 114a and 114b, and 116a and 116b, unlike the first vertical wall sections 114a and 116a, the pair of second vertical wall sections 114b and 116b located at the tip in the second rotational direction R2 have second thread guide inclined surfaces 124a and 124b formed on them, respectively, which move away from the bottom of the rod guide groove 112 in the z direction as the first thread loop shaft 92 moves toward the second rotational direction R2. The second thread guide inclined surfaces 124a and 124b move the thread T away from the radial thread grooves 118a and 118b as the first thread loop shaft 92 rotates in the first rotational direction R1.

[0047] On the outer surfaces of the pair of vertical walls 114 and 116, circumferential thread grooves 126a and 126b are formed at positions in the direction of the fifth rotation axis C5 corresponding to the groove bottoms of the radial thread grooves 118a and 118b, respectively, for determining the position of the thread T. The circumferential thread grooves 126a and 126b stably wrap the first thread loop L1 around the outer surfaces of the pair of vertical walls 114 and 116.

[0048] On the inner wall surfaces of the radial thread groove 118, specifically on the side of the first vertical wall portions 114a and 116a, thread movement inclined surfaces 128a and 128b are formed, which are directed toward the first rotational direction R1, the non-loop-forming rotational direction, as they approach the bottom of the radial thread groove 118. As a result, when the first thread loop axis 92 is rotated in the second rotational direction R2, the thread T in the radial thread grooves 118a and 118b is moved toward the bottom of the radial thread groove 118, guided toward the circumferential thread grooves 126a and 126b, and easily fitted into the circumferential thread grooves 126a and 126b.

[0049] The main body portion 98 of the second thread loop shaft 94 is also provided with a pair of vertical walls 132 and 134 sandwiching a rod guide groove 130, radial thread grooves 136a and 136b, vertical wall portions 132a, 132b and 134a and 134b divided by radial thread grooves 136a and 136b, first thread guide inclined surfaces 138a and 138b, thread engagement corners 140a and 140b, second thread guide inclined surfaces 142a and 142b, circumferential thread grooves 144a and 144b, and thread moving inclined surfaces 146a and 146b, all configured in the same way as the main body portion 96 of the first thread loop shaft 92.

[0050] (Ligamentation operation of the ligation device) The ligation operation process of the ligation device 10 configured as described above will be explained below with reference to Figures 16 to 44.

[0051] Figure 16 shows the process P1 of gripping the object to be ligated, in which the upper jaw portion 18 is opened using the ligating device 10 in which the thread T has been repositioned, and the object to be ligated 32 is inserted between the lower jaw portion 12 and the upper jaw portion 18 and gripped. In this state of the ligating device 10, the thread feed rod 64 is housed in the thread feed rod housing hole 66. The ligating thread hook 34 is advanced to the second thread hook insertion hole 80, and the repositioning thread hook 54 is retracted into the fifth thread hook insertion hole 88. The thread T unwound from the bobbin 62 is gripped by the repositioning thread hook 54 in the fifth thread hook insertion hole 88, after passing through the locking pin 67, the thread engagement portion 74 of the thread feed rod 64, the first thread hook insertion hole 38, the second thread hook insertion hole 80, and the third thread hook insertion hole 84. Then, at the position corresponding to the thread loop forming portion 90 of the ligating thread hook 34 that has been advanced, the first loop L1 and the second loop L2 formed from the thread T by the thread loop forming portion 90 are wrapped around the first thread loop shaft 92 and the second thread loop shaft 94. Figures 16 to 23 show the state in which the first loop L1 and the second loop L2 have been detached from the first thread loop shaft 92 and the second thread loop shaft 94 for ease of understanding.

[0052] In the knot pusher advancement process P2 shown in Figure 17, after closing the upper jaw portion 18 from the state of the body to be ligated gripping process P1 in Figure 16, the ligating thread hook 34 is advanced together with the knot pusher 50 to just before the opening of the thread feed rod housing hole 66 in the first thread hook insertion hole 38. In the figures from Figure 17 onward, dashed arrows indicate the direction and distance of movement of the component, and solid arrows indicate the direction of movement of the thread T caused by the movement of that component.

[0053] Next, in the ligation thread hook protrusion step P3 shown in Figure 18, the cylindrical body 46 and the thread hook gripping member 48 are protruded from the knot pusher 50 of the ligation thread hook 34 to the tip of the first thread hook insertion hole 38.

[0054] Next, in the thread feed rod protrusion step P4 shown in Figure 19, the thread feed rod 64 is raised in the z direction until it is exposed through the thread feed rod insertion hole 42 formed in the second jaw portion 18. This causes the thread T, which is attached to the thread engagement portion 74 of the thread feed rod 64, to be lifted towards the second jaw portion 18.

[0055] In the thread gripping process P5 shown in Figure 20, the thread hook gripping member 48 is reciprocated against the cylindrical body 46 of the ligating thread hook 34 to insert the thread T between the hook projection 46a and the thread hook gripping member 48, partially gripping the thread T. Then, the ligating thread hook 34 is slightly retracted until it is separated from the thread feed rod 64.

[0056] Next, in the knot pusher retraction process P6 shown in Figure 21, the thread feed rod 64 is lowered into the thread feed rod housing hole 66, and the tip of the knotting thread hook 34 is retracted together with the knot pusher 50 to the tip side position of the third hook insertion hole 84.

[0057] Next, in the first thread cutting step P7 shown in Figure 22, the ligating thread hook 34 is slightly retracted while the thread T is fully gripped by the thread hook gripping member 48 of the ligating thread hook 34, and then the thread feed rod 64 is pushed upward as far as possible in the z direction through the thread feed rod insertion hole 42 formed in the second jaw portion 18. As a result, the thread T, which has tension applied due to the retraction of the ligating thread hook 34, comes into contact with the first cutter 36 and is cut. As a result, of the separated threads T, the thread T1 distal to the body to be ligated 32 is gripped by the ligating thread hook 34, and the thread T2 proximal to it is gripped by the repositioning thread hook 54. In this state, the perimeter of the body to be ligated 32 is wrapped around the distal thread T1 and the proximal thread T2.

[0058] In the thread insertion process P8 shown in Figure 23, after the thread feed rod 64 is housed in the thread feed rod housing hole 66, the thread T1 is partially held by the thread hook gripping member 48 of the ligating thread hook 34, and the thread hook gripping member 48 of the ligating thread hook 34 and the knot pusher 50 are retracted to the base end of the ligating device 10, i.e., the fourth thread hook insertion hole 86. As a result, the thread T1 is inserted into the two second thread loops L2 and the first thread loop L1.

[0059] Next, in the thread loop removal process P9 shown in Figure 24, with the thread T1 fully gripped by the ligating thread hook 34, the pair of first thread loop shafts 92 and second thread loop shafts 94 are rotated in the first rotational direction R1, i.e., the non-loop-forming rotational direction. Through the action of the second thread guide inclined surfaces 124a and 124b of the first thread loop shaft 92 and the second thread guide inclined surfaces 142a and 142b of the second thread loop shaft 94, the first thread loop L1 wrapped around the first thread loop shaft 92 and the second thread loop L2 wrapped around the second thread loop shaft 94 are removed from the first thread loop shaft 92 and the second thread loop shaft 94. During this process, the ligating thread hook 34 is moved slightly forward and the repositioning thread hook 54 is moved slightly backward to apply tension to the threads T1 and T2 so that they do not become loose.

[0060] Next, in the thread loop movement process P10 shown in Figure 25, the repositioning thread hook 54 is slightly retracted to apply tension to the thread T2, while the thread hook gripping member 48 of the ligating thread hook 34 is advanced to the vicinity of the second cutter 82, and the knot pusher 50 of the ligating thread hook 34 is advanced to the vicinity of the object to be ligated 32, thereby moving the first thread loop L1 and the second thread loop L2 to the vicinity of the object to be ligated 32.

[0061] In the knot-forming process P11 shown in Figure 26, the repositioning thread hook 54 is advanced and the ligating thread hook 34 is retracted, causing the thread loop L1, the one of the two thread loops L1 and L2 that is closer to the knot pusher 50, to be switched (moved) from the proximal thread T2 to the distal thread T1. As a result, the knot M of the square knot shown in Figure 28 is formed from the state before knot formation in the thread loop movement process P10 shown in Figure 27. Note that in Figures 27 and 28, the entanglement of the distal thread T1 and the proximal thread T2 wrapped around the body to be ligated 32 is shown loosely to facilitate understanding of the concept of entanglement.

[0062] Next, in the second thread cutting step P12 shown in Figure 29, the knot pusher 50 is moved further towards the rear end of the tying device 10 than the second cutter 82, and the second cutter 82 is operated around the fourth rotation axis C4 from its initial retracted position to the cutting position, thereby simultaneously cutting the two threads T1 and T2 between the knot M and the tying thread hook 34 and the repositioning thread hook 54.

[0063] Next, in the thread retrieval process P13 shown in Figure 30, the second cutter 82 is operated from the cutting position to the retracted position, and the ligating thread hook 34 is pulled out from the rear end of the ligating device 10. After the remaining thread is recovered from the ligating thread hook 34, the knot pusher 50 and the ligating thread hook 34 are inserted into the fourth thread hook insertion hole 86.

[0064] In the subsequent process P14, shown in Figure 31, the second jaw portion 18 of the ligating device 10 is opened and closed to form a knot M, thereby removing the ligated body 32 that has been tied with the thread T. Figure 31 shows the state after the ligated body 32 has been removed and the second jaw portion 18 is closed.

[0065] (Repositioning of the thread in the ligating device) In the repositioning thread hook advancement process P15 shown in Figure 32, in the state shown in Figure 31, the repositioning thread hook 54 is inserted through the fifth thread hook insertion hole 88 and advanced to the first thread hook insertion hole 38. In this state, the cylindrical body 58 of the repositioning thread hook 54 has reached the tip of the first thread hook insertion hole 38.

[0066] Next, in the thread feed rod protrusion step P16 shown in Figure 33, the thread feed rod 64 is raised to near the opening of the thread feed rod insertion hole 42 formed in the second jaw portion 18.

[0067] In the thread gripping process P17 shown in Figure 34, the thread hook gripping member 60 inside the cylindrical body 58 of the repositioning thread hook 54 is advanced, and after the thread T is gripped between the notch 56 of the repositioning thread hook 54 and the thread hook gripping member 60, the repositioning thread hook 54 is moved back slightly.

[0068] Next, in the rod guide groove yarn placement process P18 shown in Figure 35, the yarn feed rod 64 is lowered and stored in the yarn feed rod housing hole 66, and the repositioning yarn hook 54 is moved back toward the base end of the knotting device 10 from the yarn loop forming section 90, which is composed of a pair of first yarn loop shafts 92 and second yarn loop shafts 94. As a result, the yarn T is placed in the rod guide groove 112 of the yarn loop shaft 92 and the rod guide groove 130 of the second yarn loop shaft 94, through which the repositioning yarn hook 54 had previously passed.

[0069] Next, in the yarn groove placement process P19 shown in Figure 36, the pair of first yarn loop axes 92 and second yarn loop axes 94 are rotated by 90 degrees in the first rotational direction R1, thereby arranging the yarn T in the rod guide grooves 112 and 130 into the radial yarn grooves 118a, 118b and 136a, 136b in directions perpendicular to the rod guide grooves 112 and 130. With the thread T stretched in the x-direction with a certain amount of tension, when the first thread loop axis 92 and the second thread loop axis 94 are rotated by 90 degrees in the first rotational direction R1, the thread T is lifted in the z (up) direction by the action of the first thread guide inclined surfaces 120a, 120b and 138a, 138b, and then falls into the radial thread grooves 118a, 118b and 136a, 136b, so that the thread T is positioned from inside the rod guide grooves 112 and 130 into the radial thread grooves 118a, 118b and 136a, 136b.

[0070] In the thread loop formation process P20 shown in Figure 37, the repositioning thread hook 54 is retracted to the fifth thread hook insertion hole 88. Then, while the repositioning thread hook 54 is advanced, the pair of first thread loop shafts 92 and second thread loop shafts 94 are rotated by 270 degrees each in the second rotation direction R2, which is opposite to the first rotation direction R1. As a result, the thread T is wound around the pair of first thread loop shafts 92 and second thread loop shafts 94, respectively, forming two first thread loops L1 and a second thread loop L2.

[0071] Next, in the thread hook placement step P21 shown in Figure 38, the knot pusher 50 of the ligating thread hook 34 is rotated around its axis as shown in Figures 39 to 44, and is advanced while passing under the threads of the first thread loop L1 and the second thread loop L2 that are wrapped around the pair of first thread loop axes 92 and second thread loop axes 94.

[0072] Figure 39 shows the state in which the knot pusher 50 is approaching the circumferential thread on the proximal end of the first thread loop L1 located on the proximal end side of the ligating device 10. When the knot pusher 50 intersects with the circumferential thread on the proximal end of the first thread loop L1, the knot pusher 50 is rotated around its axis so that its inclined end face 50a faces downward, and as shown in Figure 40, the knot pusher 50 is made to pass over the circumferential thread on the proximal end of the first thread loop L1.

[0073] Next, the knot pusher 50 is rotated around its axis and advanced so that its inclined end face 50a faces upward, and as shown in Figure 41, the knot pusher 50 passes under the radial thread of the first thread loop L1.

[0074] Next, the knot pusher 50 is rotated around its axis and advanced so that its inclined end face 50a faces downward, and the knot pusher 50 passes over the circumferential thread on the tip side of the first thread loop L1 and the circumferential thread located on the base side of the second thread loop L2, as shown in Figure 42.

[0075] Next, the knot pusher 50 is rotated around its axis and advanced so that its inclined end face 50a faces upward, and as shown in Figure 43, the knot pusher 50 passes under the radial thread of the second thread loop L2.

[0076] Then, the knot pusher 50 is rotated around its axis and advanced so that its inclined end face 50a faces downward, and as shown in Figure 44, the knot pusher 50 passes over the circumferential thread located on the tip side of the ligation device 10 of the second thread loop L2.

[0077] Thus, as shown in Figures 39 to 44, the thread T is rotated around its axis and advanced while passing under the threads of the first thread loop L1 and the second thread loop L2, which are wound around the pair of first thread loop axes 92 and second thread loop axes 94. As a result, the thread T is rearranged as shown in Figures 16 and below.

[0078] As described above, the ligating device 10 of this embodiment comprises a columnar body 14, a first jaw portion 12, a second jaw portion 18, a thread feed rod 64, and a ligating thread hook 34 and a repositioning thread hook 54, which are examples of thread pulling members. The first jaw portion 12 is connected to one end of the body 14 in the longitudinal direction. The second jaw portion 18 is connected to one end of the body 14 in the longitudinal direction so as to be movable between a holding position that holds the body to be ligated 32 between itself and the first jaw portion 12 and a separated position that is separated from the first jaw portion 12. The thread feed rod 64 is housed inside the first jaw portion 12 and has a thread engaging portion 74 at its tip that engages with the thread T used to ligate the body to be ligated 32. The thread feed rod 64 moves between a retracted position in which the thread engagement portion 74 is located within the first jaw portion 12 and a protruding position in which the thread engagement portion 74 protrudes from the first jaw portion 12 when the second jaw portion 18 is in the holding position. A ligating thread hook 34 and a repositioning thread hook 54, which are examples of thread retraction members, are housed in the main body 14. The ligating thread hook 34 has a notch 44 at its tip, which is an example of a thread hook portion for hooking the thread T that engages with the thread engagement portion 74. The repositioning thread hook 54 has a notch 56 at its tip, which is an example of a thread hook portion for hooking the thread T that engages with the thread engagement portion 74. The second jaw portion has a first thread hook insertion hole 38 and a thread feed rod insertion hole 42. The first thread hook insertion hole 38 is provided along the longitudinal direction, and the thread hook portion is inserted through it. The thread feed rod insertion hole 42 is provided along the z-direction, which is the first short-axis direction that intersects the longitudinal direction and is in the direction from the first jaw portion 12 toward the second jaw portion 18, and the thread feed rod 64 is inserted through it. The first thread hook insertion hole 38 and the thread feed rod insertion hole 42 intersect at least in part. When a notch 44 or 56, which is an example of a thread hook portion, is located on the longitudinal tip side of the second jaw portion 18 than the intersection of the first thread hook insertion hole 38 and the thread feed rod insertion hole 42, and the thread feed rod 64 is in a protruding position, the thread engagement portion 74 of the thread feed rod 64 is located downstream of the first thread hook insertion hole 38 in the z-direction, which is the first short-axis direction, i.e., away from the first jaw portion 12, and is positioned to overlap with the first thread hook insertion hole 38 in the y-direction, which is the second short-axis direction.

[0079] In the ligating device 10 of this embodiment, when the notch 44 of the ligating thread hook 34 or the notch 56 of the repositioning thread hook 54 is located on the longitudinal tip side of the second jaw portion 18 than the intersection of the first thread hook insertion hole 38 and the thread feed rod insertion hole 42, and the thread feed rod 64 is in a protruding position, the thread engaging portion 74 of the thread feed rod 64 is located on the side further away from the first jaw portion 12 than the first thread hook insertion hole 38 in the first short direction, the z direction, and is positioned to overlap with the first thread hook insertion hole 38 in the second short direction, i.e., the y direction. This allows the thread to be grasped by the thread hook and the thread T to be directly wound around the outer circumference of the body to be ligated 32.

[0080] In the tying device 10 of this embodiment, the thread feed rod 64 has a groove 76 located upstream of the thread engagement portion 74 in the first short direction, the z direction, and overlapping with the thread engagement portion 74 in the second short direction, the y direction. When the thread feed rod 64 is in a protruding position, the groove 76 is positioned to overlap with the first hook insertion hole 38 in the first short direction, the z direction. This allows the thread engagement portion 74 of the thread feed rod 64 to intersect with the notch (thread hook portion) 44 of the tying thread hook (thread pull-in member) 34 in the second short direction, the y direction.

[0081] In the ligating device 10 of this embodiment, the first thread pull-in member, the ligating thread hook 34, has a cylindrical body 46 with a notch 44 forming a thread hook portion, and a thread hook gripping member 48 that is slidably inserted into the cylindrical body 46 and grips the thread T between itself and the notch 44. Similarly, the second thread pull-in member, the repositioning thread hook 54 (thread pull-in member), has a cylindrical body 58 with a notch 56 forming a thread hook portion, and a thread hook gripping member 60 that is slidably inserted into the cylindrical body 58 and grips the thread T between itself and the notch 56. This makes it possible to grip the thread T that has been caught in the notches 44 and 56.

[0082] In the ligating device 10 of this embodiment, the notch 44 formed in the cylindrical body 46 becomes shallower in the y-direction as it approaches the tip of the cylindrical body 46. In addition, a hooking projection 46a is formed that protrudes linearly in the x-direction from the opening of the notch 44 on the side away from the tip of the cylindrical body 46. Furthermore, the tip of the thread hook gripping member 48 has an inclined surface 48a that approaches the tip as the notch 44 becomes shallower. This allows the thread T to be gripped more securely by the notch 44.

[0083] In the ligating device 10 of this embodiment, the inclined surface 46c of the cylindrical body 46 that is opposite to the inclined surface 48a at the tip of the thread hook gripping member 48 is a surface parallel to the inclined surface 48a. As a result, the inclined surface 46c of the cylindrical body 46 and the inclined surface 48a at the tip of the thread hook gripping member 48 come into contact, which suppresses rotation of the thread hook gripping member 48 around its axis relative to the cylindrical body 46, and allows the thread T to be accurately gripped by the notch 44.

[0084] In the knotting device 10 of this embodiment, the cylindrical body 46 has a flattened portion 46b with a thickness smaller than the inner diameter of the cylindrical body 46 at the tip portion from the notch 44 of the cylindrical body 46. This allows the thread T gripped between the thread hook gripping member and the flattened portion to be pulled into the knot pusher 50.

[0085] In the tying device 10 of this embodiment, the thread engagement portion 74 of the thread feed rod 64 is a groove formed along the x-direction, which is the longitudinal direction of the tying device 10. This makes it easier for the thread T to catch on the thread engagement portion 74.

[0086] In the ligating device 10 of this embodiment, a first cutter 36 for cutting the thread T is fixed to the second jaw portion 18. The cutter 36 is located longitudinally between the thread feed rod insertion hole 42 and the main body 14. As a result, the thread T can be cut by extending the thread feed rod 64 out of the first jaw member 18.

[0087] In the ligating device 10 of this embodiment, the cutter 36 is fixed to the second jaw portion 18. The thread feed rod 64 is also movable from a first protruding position to a second protruding position in the z-direction, which is the first short direction, where the thread engaging portion 74 of the thread feed rod 64 protrudes further from the first protruding position. The first protruding position is the position in which the thread feed rod protrudes from the thread feed rod insertion hole 42 in order to allow the ligating thread hook 34 to grip the thread T when the second jaw portion 18 is in the holding position. As a result, the thread T can be cut simply by moving the thread feed rod 64 without moving the cutter 36.

[0088] In the ligating device 10 of this embodiment, a bobbin (thread storage section) 62 containing the thread T is provided inside the first jaw section 12. This allows the distance between the bobbin 62 and the thread feed rod 64 to be shortened compared to when the bobbin 62 is located in a different position inside the first jaw section 12, thereby reducing wasted thread T.

[0089] In the knotting device 10 of this embodiment, the bobbin (thread storage section) 62 in which the thread T is stored is located between the thread engagement section 74 of the thread feed rod 64 and the main body 14 in the longitudinal direction of the knotting device 10. This makes it possible to reduce the longitudinal dimensions of the knotting device 10 and make it more compact.

[0090] In the knotting device 10 of this embodiment, the thread storage section includes a bobbin 62 around which the thread T is wound, and the third rotation axis C3, which is the rotation center of the bobbin 62, is parallel to the y-direction, which is the second short direction. This allows the thread T to be supplied to the thread feed rod 64 along the longitudinal direction of the knotting device 10 while suppressing twisting.

[0091] According to the ligating device 10 of this embodiment, the main body 14 includes a pair of first thread loop shafts 92 and second thread loop shafts 94 that form thread loops of thread T. The pair of first thread loop shafts 92 and second thread loop shafts 94 have rod guide grooves 112 and 130 that guide the movement of the ligating thread hook 34 and the repositioning thread hook 54 (thread pull-in member) of the ligating device 10 in the longitudinal direction, i.e., the x-direction. As a result, the retraction of the ligating thread hook 34 and the repositioning thread hook 54 (thread pull-in member) positions the thread T within the rod guide grooves 112 and 130, and the rotation of the first thread loop axis 92 and the second thread loop axis 94 forms the first thread loop L1 and the second thread loop L2, and the advancement of the ligating thread hook 34 and the repositioning thread hook 54 (thread pull-in member) within the rod guide grooves 112 and 130 provides an entanglement of the thread T to form a knot M of the thread T.

[0092] In the ligating device 10 of this embodiment, a pair of first thread loop shafts 92 and second thread loop shafts 94 are rotatably mounted around a fifth rotation axis C5 and a sixth rotation axis C6 parallel to the first short direction, i.e., the z direction, and are equipped with gears 100 and 102 that mesh with each other and are rotated in opposite directions relative to each other. As a result, a knot M of the thread T is formed using the first thread loop L1 and the second thread loop L2 formed around the fifth rotation axis C5 and the sixth rotation axis C6, respectively.

[0093] In the ligating device 10 of this embodiment, the pair of first thread loop shafts 92 and second thread loop shafts 94 each have radial thread grooves 118a, 118b and 135a and 136b, first thread guide inclined surfaces 120a, 120b and 138a and 138b, and thread engagement angles 122a, 122b and 140a and 140b, respectively. The radial thread grooves 118a, 118b and 135a and 136b are grooves aligned in a direction perpendicular to the rod guide grooves 112 and 130. The first thread guide inclined surfaces 120a, 120b and 138a, 138b are inclined surfaces that move the thread T, which has been pulled into the main body 14 by the ligating thread hook (thread pull-in member) 34 within the rod guide grooves 112, 130, into the radial thread grooves 118a, 118b and 135a, 136 as the first thread loop axis 92 and the second thread loop axis 94 rotate in the non-loop formation rotation direction R1. The thread engagement angles 122a, 122b and 140a, 140b catch the thread T in the radial thread grooves 118a, 118b and 135a, 136 as the first thread loop axis 92 and the second thread loop axis 94 rotate in the loop formation rotation direction R2, which is opposite to the non-loop formation rotation direction R1, thereby forming the first thread loop L1 and the second thread loop L2 around the fifth rotation axis C5 and the sixth rotation axis C6, respectively. As a result, a knot M of thread T is formed using the first thread loop L1 and the second thread loop L2 formed around the fifth rotation axis C5 and the sixth rotation axis C6.

[0094] In the ligating device 10 of this embodiment, the ligating thread hook (thread pull-in member) 34 has a cylindrical knot pusher (outer cylindrical member) 50 into which a cylindrical body 46 is slidably inserted and into which the cylindrical body 46 is retractably fitted, and an inclined end face 50a is provided at the tip of the knot pusher 50. This makes it possible to tighten the knot M.

[0095] The ligating device 10 of this embodiment includes a repositioning hook (second thread pull-in member) that moves between a first position parallel to the ligating thread hook (thread pull-in member) 34 and a second position coaxial with the ligating thread hook (thread pull-in member) 34. This makes it possible to reposition the thread T without increasing the size of the ligating device 10.

[0096] The ligation device 10 of this embodiment further includes a swivel section (connecting member) 30 that connects the first jaw section 12 and the second jaw section 18 to the main body 14. The base end of the second jaw section 18 is connected to the first jaw section 12 via a first pin 16 parallel to the y-direction, which is the second short direction, so that it can be opened and closed. The swivel section (connecting member) 30 is rotatably connected to the end of the cylindrical main body 14 via a second pin 28 parallel to the z-direction, which is the first short direction. As a result, the second jaw section 18 can be opened and closed relative to the first jaw section 12, and since the second jaw section 18 and the first jaw section 12 are swivelably connected to the end of the cylindrical main body 14, the degree of freedom of operation of the second jaw section 18 and the first jaw section 12 is increased.

[0097] Furthermore, the ligation device 10 of this embodiment comprises a columnar body 14, a first jaw portion 12 and a second jaw portion 18 (holding portion) connected to one end of the body 14 in the longitudinal direction and being an example of a holding portion for holding the body to be ligated 32, a repositioning thread hook 54 being an example of a thread pulling member, and a thread loop forming portion 90. The repositioning thread hook 54 is provided to be movable along the longitudinal direction within the body 14 and pulls the thread T for ligating the body to be ligated 32 into the body 14. The thread loop forming portion 90 forms two thread loops L1 and L2 on the thread T pulled into the body 14 by the repositioning thread hook 54. The thread loop forming portion 90 also has a pair of first thread loop axes 92 and second thread loop axes 94 that rotate in opposite directions around a fifth rotation axis C5 and a sixth rotation axis C6 which are parallel to each other and intersect with the movement trajectory of the repositioning thread hook 54. Each of the pair of first thread loop shafts 92 and second thread loop shafts 94 has a main body 96 and 98, a pair of vertical walls 114, 116 and 132, 134, and radial thread grooves 118a, 118b and 136a, 136b, which are examples of thread grooves. The main body 96 and 98 are positioned away from the movement trajectory and rotate around the first thread loop shaft 92 and second thread loop shaft 94. The pair of vertical walls 114, 116 and 132, 134 project from the main body 96 and 98 in directions parallel to the fifth rotation axis C5 and the sixth rotation axis C6. The pair of vertical walls 114, 116 and 132, 134 move, respectively, to a position that overlaps the movement trajectory and to a position that is separated from the movement trajectory, with the repositioning thread hook 54 in between, as the main body 96 and 98 rotate. The radial thread grooves 118a, 118b and 136a, 136b are formed at the tops of each pair of vertical walls 114, 116 and 132, 134 and engage with the thread T that is pulled in by the repositioning thread hook 54.

[0098] According to the ligating device 10 of this embodiment, a pair of first thread loop shafts 92 and second thread loop shafts 94 that rotate in opposite directions to each other around a fifth rotation axis C5 and a sixth rotation axis C6 each have a pair of vertical walls 114, 116 and 132, 134, and radial thread grooves 118a, 118b and 136a, 136b formed at the tops of each pair of vertical walls 114, 116 and 132, 134, which engage with the thread T pulled in by the repositioning thread hook 54. Therefore, when the pair of first thread loop axes 92 and second thread loop axes 94 rotate in opposite directions relative to each other around the parallel fifth rotation axis C5 and sixth rotation axis C6, the thread T is wrapped around the outer surfaces of the pair of vertical walls 114, 116 and 132, 134 respectively, forming two thread loops L1 and L2 by the proximal thread T2. Within these two thread loops L1 and L2, the ligating thread hook 34 moves distally through the two thread loops L1 and L2 to grasp the thread T1 located distal to the object to be ligated 32, and then moves backward towards the proximal side of the object to be ligated 32, so that the thread T1 located distally is passed through the thread loops L1 and L2 formed by the thread T2 on the proximal side, and a knot M is formed.

[0099] In the ligating device 10 of this embodiment, the thread pulling member includes a ligating thread hook 34, which is an example of a first thread pulling rod, and a repositioning thread hook 54, which is an example of a second thread pulling rod. The ligating thread hook 34 pulls the thread T, which is wrapped around the object to be ligated 32, into the main body 14. The repositioning thread hook 54 pulls the thread T into the main body 14 before it is wrapped around the object to be ligated 32. The movement trajectory of the ligating thread hook 34 and the movement trajectory of the repositioning thread hook 54 are coaxial at the position where they intersect with the fifth rotation axis C5 and the sixth rotation axis C6 of the pair of first thread loop axes 92 and second thread loop axes 94, respectively. This allows the ligation device 10 to be miniaturized while simultaneously forming the base of the knot M of the thread T in the thread loop forming section 90, by sharing a portion of the movement trajectory of the two ligation thread hooks (first thread pull-in rod) 34 and the repositioning thread hook (second thread pull-in rod) 54.

[0100] According to the ligating device 10 of this embodiment, each pair of vertical walls 114, 116 and 132, 134 has a pair of vertical wall portions 114a and 114b, 116a and 116b, 132a and 132b, and 134a and 134b, respectively, which are divided in the circumferential direction by radial thread grooves 118a, 118b and 136a and 136b. On one of the first vertical wall sections 114a, 116a, 132a, and 134b of the pair of vertical wall sections 114a and 114b, 116a and 116b, 132a and 132b, and 134a and 134b, first thread guide inclined surfaces 120a, 120b, and 138a, 138b are formed, respectively, which guide the thread T to the radial thread grooves 118a, 118b and 136a, 136b as the pair of i-thread loop axes 92 and second thread loop axes 92 rotate in the non-loop-forming rotation R1 direction. This makes it possible to form two thread loops L1 and L2, which are prerequisites for making a square knot, during the first rotation R1.

[0101] In the ligating device 10 of this embodiment, the other second vertical wall portions 114b, 116b, 132b, and 134b of the pair of vertical wall portions 114a and 114b, 116a and 116b, 132a and 132b, and 134a and 134b are formed on the second vertical wall portions 114b, 116b, 132b, and 134b, respectively, which move the thread T away from the radial thread groove as the first rotation of the pair of first thread loop shafts 92 and second thread loop shafts 94 in the non-loop forming rotation R1 direction. As a result, in the first rotation after the thread T has passed through the two first thread loops L1 and second thread loops L2 by the ligating thread hook 34, the first thread loops L1 and second thread loops L2 are easily detached from the first thread loop shafts 92 and second thread loop shafts 94.

[0102] In the ligating device 10 of this embodiment, on the outer circumferential surfaces of the pair of vertical walls 114, 116 and 132, 134, circumferential thread grooves 126a, 126b and 144a, 144b are formed at the same positions in the direction of the fifth rotation axis C5 and the sixth rotation axis C6 as the groove bottoms of the radial thread grooves 118a, 118b and 136a, 136b, respectively. As a result, the thread T wrapped around the outer circumferential surfaces of the pair of vertical walls 114, 116 and 132, 134 is positioned in the direction of the fifth rotation axis C5 and the sixth rotation axis C6 by the circumferential thread grooves 1216a, 126b and 144a, 144b.

[0103] In the ligating device 10 of this embodiment, on the inner wall surfaces of the radial thread grooves 118a, 118b and 136a and 136b, the inner wall surfaces on the side of the first vertical wall portions 114a, 116a, 132a, and 134a are formed, respectively, on which thread movement inclined surfaces 128a, 128b and 146a, 146b are directed toward the first rotational direction as they approach the bottom of the radial thread grooves 118a, 118b and 136a, 136b. As a result, when the pair of first thread loop axes 92 and second thread loop axes 94 are rotated a second time in the loop formation rotation R2 direction, the thread T in the radial thread grooves 118a, 118b and 136a, 136b is automatically positioned in the circumferential thread grooves 126a:126b and 144a, 144b.

[0104] Although one embodiment of the present invention has been described above with reference to the drawings, the present invention is also applicable to other embodiments.

[0105] . In the aforementioned embodiment, the yarn T is made of a ligatable, plastic wire. Preferably, the yarn T is made of natural yarn twisted from plant or animal natural fibers, synthetic resin yarn made of single or twisted strands of synthetic fibers, metal yarn made of single or twisted strands of metal, or composite yarn made of natural and synthetic fibers.

[0106] Furthermore, although the ligation device 10 in the above-described embodiment had a cylindrical cross-section, it may also have a prismatic shape with a polygonal cross-section such as a square or hexagon.

[0107] Furthermore, although the ligating device 10 of the above embodiment used two ligating thread hooks and a repositioning thread hook, a single thread pull-in member (thread hook) that has both functions may be used.

[0108] Furthermore, in the ligating device 10 of the above embodiment, two loops L1 and L2 for ligation were formed in the thread-like member T, but it is also possible to form three or more loops for ligation. That is, the thread loop forming section 90 of the ligating device 10 of the above embodiment was equipped with two first thread loop shafts 92 and a second thread loop shaft 94, but it may be equipped with three or more thread loop shafts.

[0109] Furthermore, in the ligating device 10 of the above-described embodiment, as shown in Figure 15, the first thread loop axis 92 rotated in a counterclockwise second rotation direction R2 and the second thread loop forming axis 94 rotated in a clockwise second rotation direction R2 in order to form loops L1 and L2, but they may rotate in the opposite direction. In short, the pair of first thread loop axes 92 and second thread loop forming axis 94 only need to rotate in opposite directions to each other.

[0110] Furthermore, in the ligation device 10 of the above embodiment, a swivel section 30 that rotates around the rotation axis C2 was provided on the main body 14, but the swivel section 30 is not necessarily required.

[0111] Furthermore, in the ligating device 10 of the above embodiment, the opening / closing operation wire 23 for opening and closing the second jaw portion 18, the swivel operation wire 33 for rotating the swivel portion 30, the second cutter operation wires 78a and 78b for rotating the second cutter 82, the thread feed rod operation wire 68 for moving the thread feed rod 64 between the retracted position and the protruding position, and the thread loop shaft operation wire 104 for rotating the first thread loop shaft 62 may be directly operated manually by an operator, or they may be remotely operated using an electrically driven actuator.

[0112] Furthermore, in the above-described embodiment, the first jaw portion 12 was provided via the swivel portion 30 so as to protrude longitudinally from the main body 14, and the second jaw portion 18 was rotatably provided on the swivel portion 30 so as to be able to open and close relative to the first jaw portion 12. However, conversely, the second jaw portion 18 may be provided so as to protrude longitudinally from the main body 14, and the first jaw portion 12 may be rotatably provided on the swivel portion 30. Alternatively, the first jaw portion 12 and the second jaw portion 18 may each be rotatably provided on the swivel portion 30.

[0113] Although not explicitly stated here, the present invention can be implemented in various modified and improved forms based on the knowledge of those skilled in the art. [Explanation of symbols]

[0114] 10: Ligation device 12: First jaw portion (retaining portion) 14: Main unit 18: Second jaw portion (retaining portion) 32: Ligated body 54: Repositioning thread hook (pull-in member, second thread pull-in member) 60: Thread hook gripping member (holding part) 64: Thread feed rod 74: Thread engagement part 92: First thread loop axis 94: Second thread loop axis

Claims

1. A columnar body, A holding portion is connected to one end of the main body in the longitudinal direction and holds the object to be ligated. Within the main body, a thread-pulling member is provided so as to be movable along the longitudinal direction and pulls the thread for tying the object to be tied into the main body, A ligating device comprising: a thread loop forming section that forms two thread loops in the thread that has been pulled into the main body by the thread pulling member, The thread loop forming section has a pair of thread loop axes that rotate in opposite directions around mutually parallel rotation axes that intersect the movement trajectory of the thread pulling member. The pair of thread loop axes are, A main body portion is provided at a position separated from the aforementioned movement trajectory and rotates around the rotation axis, A pair of vertical walls projecting from the main body in the direction of the rotation axis, the pair of vertical walls moving between a position overlapping the movement trajectory and a position separated from the movement trajectory as the main body rotates, Each of the pair of vertical walls has a thread groove formed at its top that engages with the thread pulled in by the pull-in member. A ligation device characterized by the following features.

2. The thread pulling member comprises a first thread pulling rod for pulling the thread wrapped around the object to be tied into the main body, and a second thread pulling rod for pulling the thread into the main body before it is wrapped around the object to be tied. The movement trajectory of the first thread pull-in rod and the movement trajectory of the second thread pull-in rod are coaxial at the point where they intersect with the respective rotation axes of the pair of thread loop axes. A ligation device according to feature 1.

3. Each of the pair of vertical walls has a pair of vertical wall portions that are divided in the circumferential direction by the thread groove, A first thread guide inclined surface is formed on one of the pair of vertical wall portions, which guides the thread into the thread groove as the pair of thread loop axes rotate for the first time. The ligation device according to feature 2.

4. The other of the pair of vertical wall sections is formed on the second vertical wall section, which has a second thread guide inclined surface that moves the thread away from the thread groove as the first rotation of the pair of thread loop axes occurs. The ligation device according to feature 3.

5. On the outer circumferential surfaces of the pair of vertical walls, circumferential thread grooves are formed at the same position as the groove bottom of the thread groove in the direction of the rotation axis, and these grooves are continuous in the circumferential direction. The ligation device according to feature 4.

6. On the inner wall surface of the thread groove, the inner wall surface on the side of the first vertical wall portion has an inclined surface that is directed toward the first rotational direction as it approaches the bottom of the thread groove. Ligation device according to feature 5.

7. The pair of thread loop shafts each have gears that mesh with each other. A ligation device according to feature 1.

8. The first thread-pulling member has a thread hook portion at its tip for catching the thread. The ligation device according to feature 2.

9. The first thread-pulling member comprises a cylindrical body having a notch that constitutes the thread hook portion, and a thread hook gripping member that is slidably inserted into the cylindrical body and grips the thread between itself and the notch. Ligation device according to feature 8.

10. The notches formed in the cylindrical body are made shallower towards the tip of the cylindrical body. A hooking projection is formed that extends linearly from the opening of the notch toward the end of the cylindrical body, The tip of the thread hook gripping member has an inclined surface that slopes towards the tip, with the shallower the notch. The ligation device according to feature 9.

11. The surface inside the cylindrical body that faces the inclined surface at the tip of the thread hook gripping member is a surface parallel to the inclined surface. Ligation device according to the 10th feature.

12. The first thread-pulling rod comprises an outer cylindrical member into which the cylindrical body is slidably fitted, The rod guide groove formed between the pair of vertical walls guides the movement of the outer cylindrical member. The ligation device according to feature 11.

13. The second thread pull-in rod moves between a first position parallel to the first thread pull-in rod and a second position coaxial with the thread pull-in rod. The ligation device according to feature 2.

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