Clip unit for ligation device

Abstract

To provide a clip unit for a ligation device capable of gripping one wall surface of a large wound, reliably closing the wound by bringing the gripped one wall surface close to the other wall surface and bringing both side parts of mated paired hole walls close to the paired hole walls, and being placed in a body cavity.SOLUTION: A clip unit comprises a clip unit body 8a including a four-pronged arm part 11, and a fastening ring 30. The four-pronged arm part 11 includes first and second arm legs 12 and 13, the tip sides of which are slightly opened and that generate accumulation return force when the legs are closed, and third and fourth arm legs 14 and 15, the tip sides of which are wide opened and that generate accumulation return force when the legs are closed. When the fastening ring 30 is located at a first fitting position C, tip portions 12c and 13c of the first and second arm legs 12 and 13 are closed together, and when the fastening ring 30 is located at a second fitting position B, the tip portions 14c and 15c of the third and fourth arm legs 14 and 15 are closed together.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention is provided as a tip member of a ligation device, which is an endoscopic treatment tool that is passed through a channel of an endoscope, guided to a position facing an arbitrary affected part in the digestive tract, sandwiches the affected part, and performs hemostasis or the like. The present invention relates to a clip unit for a ligation device that is inserted into a body cavity of a living body, sandwiches an affected part to perform hemostasis or the like, and is separated as it is and left in the digestive tract.

Background Art

[0002] A ligation device includes an operation part located on the proximal end side of a channel of an endoscope, a flexible inner sheath connected to the operation part via a coupling part, a flexible outer sheath fitted from the tip position of the coupling part to the tip position of the inner sheath, an operation wire extending from a slider of the operation part in the forward direction and inserted near the tip inside the inner sheath, a connection release tool provided at the tip inside the tip of the inner sheath, and a clip unit having an arm part that is opened by elasticity and closed by being tightened by a tightening ring, and the base end part is chucked by the connection release tool.

[0003] In the clip unit of the ligation device, from a state where the open arm part is set at a position where it can sandwich an affected part in the digestive tract, the inner sheath is moved forward by an operation in the operation part, so that the tightening position of the tightening ring is moved forward by the tip part of the inner sheath, and the arm part becomes a closed state to sandwich the affected part in the digestive tract. In this state, the connection release tool is released from the chucking, and the clip unit is separated from the ligation device and left in the digestive tract.

[0004] Examples of the clip unit of the conventional ligation device include Patent Document 1 and Patent Document 2.

[0005] The clip unit described in Patent Document 1 is equipped with sharp projections near the claws at the tips of a pair of arm plates. For example, when suturing together the two sides of a mucosal defect after excision of a tumor, the projections pierce the mucosa, allowing the claws of the pair of arm plates to grip the two sides of the mucosal defect without slipping. By gripping the two sides of the mucosal defect with the pair of claws, the defect can be sutured, and the wound can be closed as long as the size of the wound is within the range of the two arm legs extended.

[0006] The clip unit described in Patent Document 2 includes an arm leg with a claw at its tip, an arm tip leg with a claw at its widely opening end relative to the arm leg, and an arm branching leg that branches off from the middle of the arm tip leg and has a claw at its narrowly opening end relative to the arm leg. As the clamping ring is moved toward the tip of the arm leg, the gap between the narrowly opening arm leg and the arm branching leg narrows, gripping one edge of the wound opening. By moving this gripped edge of the wound opening toward the other edge and moving the clamping ring toward the arm tip beyond the branching point, a wide-open wound can be easily clamped. This allows clamping one wall surface of the affected area, which is in a hole state after the lesion has been excised, moving the clamped wall surface to the other wall surface, suturing the walls together, and preventing the affected area from being exposed after suturing. [Prior art documents] [Patent Documents]

[0007] [Patent Document 1] Japanese Patent Publication No. 2015-8858 [Patent Document 2] Japanese Patent Publication No. 2017-176335 [Overview of the project] [Problems that the invention aims to solve]

[0008] The clip unit described in Patent Document 1 may be able to suture wounds with holes of 6 mm or less, but it is difficult to suture larger holes. When suturing a wound (hole) of a lesion, in surgical cases sutures are made with thread, but when suturing a hole using an endoscope, a method of suturing the walls on both sides of the lesion hole is required, making it difficult to apply to suturing wounds of lesions larger than 6 mm. For example, it is impossible to hook one wall with one claw and move it to the other wall, and then hook the other wall with the other claw to suture the walls on both sides of the lesion hole.

[0009] The clip unit described in Patent Document 2 clamps one wall surface of the wound with an arm leg and an arm branch leg and moves to the other wall surface of the wound. However, a considerable load is placed on the arm leg and the arm branch leg at this time, so the arm leg and the arm branch leg require great strength and springiness.

[0010] Furthermore, it is important that the clip unit described in Patent Document 2 has sufficiently high springiness in the arm legs, arm tip legs, and arm branch legs for the following reasons. Specifically, in terms of its configuration, the opening width of the arm legs and arm branch legs is half that of the clip unit described in Patent Document 1. Moreover, in order to pass the endoscope through, the arm legs, arm tip legs, and arm branch legs are inserted into the flexible sheath in a closed state. However, if the springiness is poor, the opening width of the arm legs and arm branch legs will inevitably shrink after insertion. This creates a problem where the opening width does not return to a sufficiently open state due to the springiness and shrinks, making it impossible to ensure the width for gripping the wall surface of the affected area. To avoid this, special metals or special manufacturing methods, such as the selection of metal materials with high springiness, are required. Currently, the three-pronged arm structure, which includes arm legs, arm end legs, and arm branching legs, presents manufacturing challenges. Laser cutting and etching methods are unsuitable because they cause material deterioration at high temperatures, and sulfuric acid can eliminate springiness. Therefore, press processing is the only feasible method for manufacturing the product. However, the press processing is complex, and it is difficult to ensure the correct opening width between the arm legs and arm end legs, making manufacturing currently impractical.

[0011] The present invention has been made in view of the above circumstances, and aims to provide a clip unit for a ligation device that has a four-pronged structure with two pairs of openable and closable arms, and has the function of being able to grasp one wall surface of a large wound with one pair of arms, bring one wall surface closer to the other wall surface, and then bring both sides of the joined opposing holes together with the other pair of arms to securely close the wound and leave it in the body cavity. [Means for solving the problem]

[0012] The first embodiment of the present invention, in order to achieve the above objective, is inserted through the channel of an endoscope and into the body cavity of a living organism to grasp the affected area. Stop the bleeding A clip unit for a ligation device, which is detachably attached to the tip of the ligation device used for the procedure, and which is detached after the procedure and remains inside the body, A base end connecting portion that is chucked by a release tool connected to the tip of the operating wire of the ligating device, and from the base end connecting portion Having elasticity It has a four-pronged arm section having extending first to fourth arm legs and each arm leg tip having a claw, and a tightening ring fitted onto the base end side of the four-pronged arm section and provided to be slidable toward the tip by operation of the ligation device, The aforementioned four-pronged arm section begins to widen midway, and its tip is bifurcated with the required spacing between them. The accumulated restorative force that tries to expand in the opening direction against the tightening force in the closing direction The increasing size of the first and second arm legs, and the bifurcated shape that begins to widen from the middle of the first and second arm legs, with the tip having a requiredly larger gap than the first and second arm legs. The accumulated restorative force that tries to expand in the opening direction against the tightening force in the closing direction The configuration includes the aforementioned enlarged third and fourth arm legs.

[0013] Furthermore, the base end of the first arm leg and the base end of the third arm leg are aligned side by side, and the base end of the second arm leg and the base end of the fourth arm leg are aligned side by side, and the initial fitted position is when the four corners of the cross-section of the base ends of the first to fourth arm legs abut against the inner circumferential surface of the clamping ring. The configuration is such that when the clamping ring moves to a first clamping position a required distance away from the initial fitting position in the direction of the tip, the tip portions of the first and second arm legs close together, and when the clamping ring moves to a second clamping position a required distance away in the direction of the tip, the tip portions of the first to fourth arm legs close together.

[0014] The second embodiment of the present invention, in addition to the configuration of the first embodiment, The first and second arm legs each include a base end portion that extends integrally from the base end connecting portion and is the initial fitting position of the clamping ring, a first widening portion that extends in an inclined manner in the middle portion, and a first clamping portion that extends substantially parallel to each other at the tip portion. The third and fourth arm legs are configured to include a base end portion that extends integrally from the base end connecting portion and is the initial fitting position of the clamping ring, a second widening portion that is an intermediate portion that curves and extends outward, and a second clamping portion that is an end portion that has a predetermined intersection angle so as to gradually open outward toward the end.

[0015] The third embodiment of the present invention, in addition to the configuration of the second embodiment, The configuration is such that when the clamping ring moves from the initial fitted position to a first clamping position a required distance away in the direction of the tip, the clamping ring tightens the first spreading portion in the middle of the first and second arm legs, causing the first clamping portion at the tip to close together. Furthermore, when the clamping ring moves to a second clamping position a required distance away in the direction of the tip, the clamping ring tightens the second spreading portion in the middle of the third and fourth arm legs, then tightens the second clamping portion at the tip, causing the second clamping portions of the third and fourth arm legs to close together.

[0016] The fourth embodiment of the present invention, in addition to the configuration of the first embodiment, The pair of claws at the tips of the first and second arm legs are oriented toward the opening / closing center and are arranged to overlap front to back when the tips of the first and second arm legs are closed together. The pair of the claws provided at the tips of the third and fourth arm legs face toward the opening / closing center, and are configured to overlap with each other in the front-rear direction when the tip sides of the first and second arm legs are closed.

[0017] The fifth invention aspect of the present application is, in addition to the configuration of any one of the first to fourth invention aspects, near each tip portion of the first and second arm legs and Each of the portions extending from the vicinity of the tip the claws extend in the direction opposite to the plate width direction with respect to the third and fourth arm legs and are formed wide. near each tip portion of the third and fourth arm legs and Each of the portions extending from the vicinity of the tip the claws extend in the direction opposite to the plate width direction with respect to the first and second arm legs and are formed wide.

[0018] The sixth invention aspect of the present application is, in addition to the configuration of any one of the first to fourth invention aspects the four-armed portion has a plurality of protrusions that the fastening ring can overcome and that contact the fastening ring to prevent movement toward the base end side at each of an initial fitting position where the fastening ring is fitted on the base end sides of the first to fourth arm legs, a first fastening position of the fastening ring when the pair of first clamping portions of the first and second arm legs are closed, and a second fastening position of the fastening ring when the pair of second clamping portions of the third and fourth arm legs of the fastening ring are closed.

Effect of the Invention

[0019] According to the present invention, there is provided a clip unit for a ligation device having a four-armed structure with two pairs of openable / closable arm portions, capable of gripping one wall surface of a large wound with one pair of arm portions, approaching the one wall surface to the other wall surface, and then closing the wound securely by bringing both side portions of the paired hole walls joined by the other pair of arm portions closer to the paired hole walls and leaving it in the body cavity.

Brief Description of the Drawings

[0020] [Figure 1]This is an exploded perspective view showing the overall schematic configuration of a ligation device including a clip unit, relating to an embodiment of the clip unit of the present invention. [Figure 2] (A) is an enlarged cross-sectional view of the tip of the ligating device including a release tool that chucks the clip unit, and (B) is an enlarged cross-sectional view of the tip of the ligating device with the clip unit chucked by the release tool. [Figure 3] The present invention relates to an embodiment of the clip unit, where (A) is a perspective view of the clip unit in the open state, (B) is an exploded perspective view of the clip unit, (C) is an exploded perspective view of the four-pronged arm portion constituting the clip unit during assembly and manufacturing, and (D) is an exploded perspective view of the four-pronged arm portion constituting the clip unit according to a modified embodiment during assembly and manufacturing. [Figure 4] Figure (A) is a perspective view showing the four-pronged arm section in an open state, Figure (B) is a perspective view showing the clip unit in an open state, Figure (C) is a perspective view showing the first and second arm legs being tightened together by the tightening ring and closed, and Figure (D) is a perspective view showing the first to fourth arm legs being tightened together by the tightening ring and closed. [Figure 5] The present invention relates to an embodiment of the clip unit, where (A) is a front view of the clip unit in the open state, (B) is a rear view of the clip unit in the open state, (C) is a front view showing the first and second arm legs being tightened together by the tightening ring, and (D) is a front view showing the first to fourth arm legs being tightened together by the tightening ring. [Figure 6]Figure (A) shows the clip unit according to an embodiment of the present invention being attached to a ligation device. Figure (A) is a side view showing part of the arrangement before the base end connecting portion is chucked by the release tool of the ligation device with the four-pronged arm portion of the clip unit open. Figure (B) is a side view showing the state after the inner sheath has been advanced from the state in Figure (A) until it covers the release tool and tightening ring, closing the legs of the release tool and chucking the base end connecting portion of the clip unit with the release tool. Figure (C) is a front view of the same state as in Figure (B). Figure (D) is a front view showing the state after the outer sheath has been advanced from the state in Figure (C) until it covers the clip unit, causing the first to fourth arm legs to be retracted by the outer sheath. [Figure 7] Figure (A) shows the clip unit according to an embodiment of the present invention in a closed position. Figure (A) is a front view (same as Figure (C) in Figure 5) showing the outer sheath retracted from the state shown in Figure (A) to a position where it does not cover the coupling release device. Figure (B) is a front view showing the tightening ring moved to the first tightening position by advancing the inner sheath relative to the operating wire and coupling release device from the state shown in Figure (A), thereby closing the first and second arm legs together. [Figure 8] Figure (A) shows the clip unit according to an embodiment of the present invention being closed and then separated. Figure (B) is a side view showing the state in which the clamping ring is moved to the second clamping position by moving it further forward from the state shown in Figure 6(B), and the first to fourth arm legs are closed together. Figure (B) is a side view showing the state in which the chuck of the base end connecting part of the clip unit is released by opening the connecting release device due to the energy recovery force, by moving the inner sheath relatively backward from the state shown in Figure (A) to a position where it does not cover the connecting release device. [Figure 9]Figure (A) is a perspective view showing the first and second arm legs of a ligation device equipped with a clip unit according to an embodiment of the present invention being brought into contact with one wall of a large open wound (affected area) in biological tissue, such as the digestive organ. Figure (B) is a perspective view showing the first and second arm legs being closed from the state in Figure (A) and gripping one wall of the wound with the first and second arm legs. Figure (C) is a perspective view showing the first and second arm legs being moved from the state in Figure (B) toward the other wall of the wound, bringing one wall of the wound closer to the other wall. Figure (D) is a perspective view showing the third and fourth arm legs being closed from the state in Figure (C) and gripping and bringing together the sides of both walls of the wound. [Modes for carrying out the invention]

[0021] Hereinafter, a clip unit for a ligation device according to an embodiment of the present invention will be described with reference to the drawings.

[0022] [About ligation devices] A ligation device is inserted through the channel of an endoscope and used to clamp onto living tissue, such as any affected area within the digestive tract, to stop bleeding. The clip unit constitutes the tip of the ligation device and is operated by the control unit of the ligation device to clamp onto the affected area and stop bleeding. Therefore, the general configuration of the ligation device will be explained first.

[0023] Figure 1 shows an exploded perspective view illustrating the schematic configuration of the ligation device 1. The ligation device 1 has an operating unit 2 operated by a physician or other medical professional. The portion of the device beyond the operating unit 2 is inserted into the channel of the endoscope until it is just before insertion into the channel. The outer sheath 5, inner sheath 4, release device 7, and clip unit 8 then protrude from the end of the channel and are inserted to any affected area within the digestive tract.

[0024] The ligation device 1 comprises an operating unit 2, a male cylindrical connecting part 3a provided at the tip of the cylindrical shaft part 2a of the operating unit 2, a female cylindrical connecting part 3b connected to the male cylindrical connecting part 3a by fitting or screwing, a flexible inner sheath 4 extending integrally forward from the tip surface of the female cylindrical connecting part 3b, a flexible outer sheath 5 fitted over the outside of the inner sheath 4 and slidable, an operating wire 6 connected to the slider 2b of the operating unit 2 and inserted so as to extend into the tip of the inner sheath 4, a release tool 7 housed in the tip of the inner sheath 4 with its base end connected to the tip of the operating wire 6, and a clip unit 8 with its base end chuck-connected to the release tool 7.

[0025] A large-diameter cylindrical knob 5a is fitted and fixed to the base end of the outer sheath 5, allowing the doctor to slide the outer sheath 5 relative to the inner sheath 4 by pinching the knob 5a with their fingers and pushing or pulling it axially. The inner sheath 4 includes an inner sheath body 4a made of, for example, a tightly wound rectangular cross-section stainless steel wire, and a retaining cylinder 4b made of, for example, a stainless steel pipe, which is extended and connected to the tip of the inner sheath body 4a.

[0026] As shown in Figure 2(A), the retaining cylinder 4b has a tightening ring housing portion 4b1 that can accommodate the tightening ring 30 inside its tip, and a chuck tightening portion 4b2 behind it.

[0027] The operating section 2 includes a cylindrical shaft portion 2a, which is divided into two parts by a slit 2a1 passing through its diameter for a predetermined length from its base end; a slider 2b that slides axially and has a diameter connecting portion 2b1 fitted onto the outer circumferential surface of the base end of the cylindrical shaft portion 2a and inserted through the slit 2a1; and a finger ring 2c attached to the base end of the cylindrical shaft portion 2a. The slider 2b has a finger portion 2b2.

[0028] As shown in Figure 2(A), the coupling release device 7 is a spring-like molded body, with a base end that is closed and located inside the inner sheath 4, connected to the tip of the operating wire 6, and having a bifurcated arm that gradually opens wider from the base end, with inwardly facing chuck jaws at each tip.

[0029] When the inner sheath 4 is moved forward, the chuck-tightening portion 4b2 of the inner sheath body 4a comes into contact with the bifurcated arm of the coupling release device 7, and the external pressure of the chuck-tightening portion 4b2 acts upon it. reserve The legs are designed to close while increasing the restorative force, which allows the pair of inwardly facing chuck jaws 7a and 7b to chuck the end face of the base end connecting portion 10 of the clip unit 8.

[0030] The ligation device 1 allows a physician to slide the slider 2b towards the rear end by placing their fingers on the finger ring 2c and the finger portion 2b2 of the slider 2b, thereby reducing the distance between the finger ring 2c and the finger portion 2b2. This allows the inner sheath 4 to move towards the front end to a position where it covers the release mechanism 7 (see Figures 2(B), 6(B), and 7(A)), and further to a position where it covers the clip unit 8 (see Figures 7(B) and 8(A)). The physician can also move the entire device forward or backward by placing their fingers on the finger ring 2c and pushing or pulling it towards the front or base end.

[0031] However, the configuration of the operating unit 2 and the coupling release device 7 is not limited to the above configuration.

[0032] [Configuration of Clip Unit 8] As shown in Figures 3(A), (B), and (C), the clip unit 8 for the ligation device consists of a clip unit body 8a and a tightening ring 30 fitted to the initial fitting position A (position in Figure 3(A)) near the base end of the clip unit body 8a. The clip unit body 8a consists of a base end connecting portion 10 that is chuck-connected to the coupling release tool 7 of the ligation device 1, and a four-pronged arm portion 11 that extends integrally forward from the base end connecting portion 10 and has claws at the tips of each arm. The tightening ring 30 can be any cylindrical molded body with the required diameter that does not expand in diameter. In the illustrated example, it is cylindrical, but it may also be rectangular or even coiled.

[0033] As shown in Figures 3(A) and 4(A) and (B), the clip unit 8 is detachably attached to the tip of the ligation device 1, with its base connecting portion 10 being connectable and disconnectable by the connecting release tool 7 of the ligation device 1. It is inserted into the body cavity of a living organism, and the four-legged arm portion 11 closes in two stages from an open state to the form shown in Figure 4(D), clamping the affected area to stop bleeding, etc. After the procedure, the connecting release tool 7 releases the chuck, separating it from the ligation device 1 and leaving it in the body cavity.

[0034] [Configuration of the base connection part 10] As shown in Figures 6(A) and 6(B), the base connecting portion 10 may be configured to be detachable by the ligation device 1's detachment tool 7. In this embodiment, the base connecting portion 10 is not a separate part from the four-legged arm portion 11, but rather, for example, is formed integrally with the four-legged arm portion 11 by press forming of a stainless steel plate. As shown in Figures 3(B) and 4(A), the base connecting portion 10 in this embodiment is a three-sided frame portion including an end face portion 10a that is held by a pair of chuck jaws 7a and 7b of the ligation device 1's detachment tool 7, and inverted trapezoidal side portions 10b, 10b that are bent at right angles from a pair of opposite sides of the end face portion 10a and whose width increases as they move away from the end face portion 10a.

[0035] [Configuration of the four-legged arm section 11] As shown in Figures 3(A)-(C) and 4(A)-(D), the four-legged arm section 11 includes first and second arm legs 12 and 13 which are formed by press forming of a stainless steel plate and bent in the thickness direction to a small opening of, for example, about 6 mm, and third and fourth arm legs 14 and 15 which are formed by press forming and are opened to a large opening of, for example, about three times.

[0036] The first and second arm legs 12 and 13 are spread slightly apart, for example, 6-8 mm, while the third and fourth arm legs 14 and 15 are spread wider, for example, about three times the spread of the first and second arm legs 12 and 13.

[0037] Figure 3(C) is an exploded perspective view showing an example of the manufacturing process of the clip unit body 8a.

[0038] In this embodiment, the third and fourth arm legs 14 and 15 are shaped by press forming so that their base ends are the same width as the base end connecting portion 10, and then bent by press forming to open even wider. The portions of the third and fourth arm legs 14 and 15 other than their base ends are half the width of the wide base ends of the third and fourth arm legs 14 and 15.

[0039] Furthermore, the first and second arm legs 12 and 13 are press-formed to half the width of the wide base ends of the third and fourth arm legs 14 and 15, and then bent by press-forming to open them even smaller. The base ends of the first and second arm legs 12 and 13 then abut against the stepped portion in the plate width direction of the base ends of the third and fourth arm legs 14 and 15, and the step contact surface and the side contact surface are integrated by laser welding, thereby giving the base ends of the first and second arm legs 12 and 13 sufficient weld strength.

[0040] As can be seen from Figures 3 and 4, the plate thickness of the first to fourth arm legs 12-15 is visible when viewed from a direction perpendicular to the opening direction, the first and second arm legs 12 and 13 appear to have a slightly open bent shape, and the third and fourth arm legs 14 and 15 appear to have a widely open bent shape.

[0041] Figure 3(D) is an exploded perspective view showing another example of the manufacturing process of the clip unit body 8a. In this modified example, the first and second arm legs 12, 13 and half of the base end connecting portion 10 are integrally formed in a bifurcated arm shape, and the third and fourth arm legs 14, 15 and the other half of the base end connecting portion 10 are integrally formed in a bifurcated arm shape, resulting in a two-part structure. In this modified example, the halves of the base end connecting portion 10 are joined together, and the base ends 12a, 13a of the first and second arm legs 12, 13 are joined to the base ends 14a, 15a of the third and fourth arm legs 14, 15, thus increasing the joining strength and strongly maintaining the elastic shape of the bifurcated arm during molding.

[0042] As yet another variation, the base ends of the first and second arm legs 12 and 13 may be wide and press-formed integrally with the base end connecting portion 10, while the base ends of the separately press-formed third and fourth arm legs 14 and 15 may be in contact with the base end connecting portion 10 and the base ends of the first and second arm legs 12 and 13 and laser-welded.

[0043] As can be seen from Figures 3(B) and 4(A), the clip unit body 8a has the base end 12a of the first arm leg 12 and the base end 14a of the third arm leg 14 integrated side by side in the width direction of the plate, and the base end 13a of the second arm leg 13 and the base end 15a of the fourth arm leg 15 integrated side by side in the width direction of the plate, and the clamping ring 30 is fitted to the base ends of the first to fourth arm legs 12 to 15 in such a state that the four corners of the cross-sectional shape perpendicular to the longitudinal direction of the base ends of the first to fourth arm legs 12 to 15 abut against four places on the inner circumferential surface of the clamping ring 30.

[0044] Furthermore, with reference to Figures 3(A) and 4(A), the bending and opening shapes of the first to fourth arm legs 12-15 and the effect of the clamping force of the clamping ring 30 will be described in detail.

[0045] The first and second arm legs 12 and 13 maintain a bent and open shape when the clamping ring 30 is in the initial fitted position A. This shape includes base ends 12a and 13a of a required length that extend integrally forward from the side portions 10b and 10b of the base end connecting portion 10, first spreading portions 12b and 13b that extend outward in an inclined linear manner from the base ends 12a and 13a, and first clamping portions 12c and 13c that extend substantially parallel to each other from the first spreading portions 12b and 13b. When the clamping ring 30 reaches the first clamping position B, the base ends of the first clamping portions 12c and 13c close together, with the first spreading portions 12b and 13b and the first clamping portions 12c and 13c closing together.

[0046] The third and fourth arm legs 14 and 15 maintain a bent and open shape when the clamping ring 30 is in the initial fitted position A. This shape includes a base end portion 14a and 15a of a required length that extends integrally from the side portions 10b and 10b of the base end connecting portion 10, a second spreading portion 14b and 15b that curves outward from the base end portion 14a and 15a, and a second clamping portion 14c and 15c that have a predetermined intersection angle so as to gradually open outward from the second spreading portion 14b and 15b toward the tip. The second spreading portions 14b and 15b do not begin to close together when the clamping ring 30 is in the first clamping position B, and when the clamping ring 30 is in the second clamping position C, the second clamping portions 14c and 15c close together and toward each other.

[0047] The base ends of the first spreading portions 12b and 13b are near the tightening ring 30 at the first fitting position near the base end of the quadruple arm portion 11 when the tightening ring 30 is fitted to that position. At this time, the tightening force of the tightening ring 30 does not act on the first spreading portions 12b and 13b, so the first clamping portions 12c and 13c are slightly open to the required spacing during press molding, and when the tightening force of the tightening ring 30 is applied, they close in the same direction. reserve Increases recovery power.

[0048] The arc-shaped base ends of the second flared portions 14b and 15b are located a required distance ahead of the base ends of the first flared portions 12b and 13b, and are located near the front where the tightening force of the tightening ring 30 does not act when the tightening ring 30 is in the first tightening position B where the first flared portions 12b and 13b are closed. The second flared portions 14b and 15b are widely open to the required distance during press molding, and when the tightening force of the tightening ring 30 is applied, they close in the same direction. reserve Increases recovery power.

[0049] Approximately half of the tip ends of the first clamping portions 12c and 13c extend broadly outward in the plate width direction (in the direction opposite to the third and fourth arms). Similarly, approximately half of the tip ends of the second clamping portions 14c and 15c extend broadly outward in the plate width direction (in the direction opposite to the first and second arms), so that the clamping ring 30 does not move any further towards the tip when all arms are closed as shown in Figure 4(D). Furthermore, the claws 16 and 17 extending from the respective tips of the first clamping portions 12c and 13c are arranged to face each other in an anti-interference manner. Similarly, the claws 18 and 19 extending from the respective tips of the second clamping portions 14c and 15c are arranged to face each other in an anti-interference manner.

[0050] As shown in Figures 4 and 5(A)-(D), the four-legged arm section 11 has an initial fitting position A (Figure 5(A)) where the tightening ring 30 is fitted to the base end side of the first to fourth arm legs 12-15, a first tightening position B (Figure 5(C)) of the tightening ring 30 when the pair of first clamping portions 12c, 13c of the first and second arm legs 12, 13 are closed together, and the tightening ring 30 is fitted to the third and fourth arm legs 14, 15 At each of the second tightening positions C (Figure 5(D)) of the tightening ring 30 when the pair of second clamping portions 14c and 15c are closed together, the tightening ring 30 can overcome the protrusions 20a and 20b that, after overcoming the protrusions, contact the base end portion of the tightening ring 30 to prevent it from moving towards the base end. Each arm leg, due to its energy recovery force, tries to push the ring back towards the base end as it expands in the opening direction in response to the tightening of the tightening ring 30 in the closing direction. At this time, the base end of the tightening ring 30 contacts each protrusion, so that the tightening ring 30 is positioned at the first tightening position B and the second tightening position C, respectively, without returning towards the base end.

[0051] [Regarding the movement of the tightening ring 30] The movement of the tightening ring 30 from its initial fitted position A to the first tightening position B, and further to the second tightening position C, can be performed by moving the slider 2b of the operating unit 2 forward relative to the cylindrical shaft portion 2a.

[0052] Figure 4(A) shows a perspective view of the clip unit body 8a (a molded body consisting of the base connecting portion 10 and the four-pronged arm portion 11; configuration excluding the tightening ring 30; see Figure 3(B)). Figure 4(B) shows the state in which the tightening ring 30 is forcibly fitted to the initial fitting position A of the clip unit body 8a. In this state, the tightening ring 30 does not apply a tightening force to the four-pronged arm portion 11, and the first to fourth arm legs 12-15 are spread in a four-pronged configuration as in the initial assembly form.

[0053] Figures 4(C) and 5(C) show the state in which the tightening ring 30 has moved from the initial fitting position A of the clip unit body 8a to the first tightening position B. As can be seen from Figures 7(A) and (B), the movement of the tightening ring 30 from the initial fitting position A to the first tightening position B is performed by moving the inner sheath 4 forward. When the tightening ring 30 is in the first tightening position B, it tightens the first spreading portions 12b and 13b of the first and second arm legs 12 and 13, causing the first and second arm legs 12 and 13 to close together, and the pair of claws 16 and 17 pass each other and overlap front to back, facing toward the opening and closing center.

[0054] Figures 4(D) and 5(D) show perspective views of the state in which the tightening ring 30 has moved to the second tightening position C of the clip unit body 8a. As can be seen from Figures 7(B) and 8(A), the movement of the tightening ring 30 from the first tightening position B to the second tightening position C is achieved by moving the inner sheath 4 further forward. When the tightening ring 30 is in the second tightening position C, it tightens the second clamping portions 14c and 15c of the third and fourth arm legs 14 and 15, and the third and fourth arm legs 14 and 15 close together in addition to the first and second arm legs 12 and 13, and the pair of claws 18 and 19 pass each other and overlap front and back, facing toward the opening and closing center. Furthermore, as the tightening ring 30 moves while tightening the second spreading portions 14b and 15b located in front of the second clamping portions 14c and 15c at the second tightening position C, the third and fourth arm legs 14 and 15 close together.

[0055] [Explanation of treatment procedures] Referring to Figures 4-9, the procedure on the affected area within the digestive tract will be explained using the ligation device 1 with the clip unit 8 attached.

[0056] As shown in Figure 6(A), in order to attach the clip unit 8 to the tip of the ligation device 1, the inner sheath 4 and outer sheath 5 are set to a retracted position so as not to overlap the coupling release tool 7, thereby opening the pair of chuck jaws 7a and 7b of the coupling release tool 7. Then, the base end coupling portion 10 of the clip unit 8 is set to a relative position where it is held by the pair of chuck jaws 7a and 7b of the coupling release tool 7.

[0057] Then, as shown in Figures 6(B) and (C), the inner sheath 4 is moved forward to a position where it covers the release tool 7. This allows the pair of chuck jaws of the release tool 7 to close together due to the external pressure of the inner sheath 4, and the base end connecting portion 10 of the clip unit 8 to be chucked. In this state, the four-pronged arm portion 11 of the clip unit 8 is still open.

[0058] Next, the portion of the outer sheath 5 of the ligation device 1 that is ahead of the gripping portion 5a at its base is inserted into the channel of the endoscope. However, if the four-pronged arm portion 11 is open, it cannot be inserted into the channel of the endoscope, so the gripping portion 5a at the base of the outer sheath 5 is grasped and advanced so that the tip of the outer sheath 5 covers the outside of the clip unit 8, as shown in Figure 6(D). This narrows the four-pronged arm portion 11, and the clip unit 8 is housed inside the tip of the outer sheath 5.

[0059] Next, the ligation device 1 is advanced so that the insertion portion of the endoscope, which is inserted into the channel of the endoscope in the state shown in Figure 6(D), is brought closer to the affected area in the digestive tract. Furthermore, the clip unit 8, covered by the outer sheath 5, is advanced to the vicinity of the affected area in the digestive tract. Then, as shown in Figure 7(A), the inner sheath 4 is held in place over the coupling release tool 7 and the finger ring 2c which is fitted in the initial fitting position A, and the knob 5a of the outer sheath 5 is grasped to retract the outer sheath 5 to a position where it does not cover the four-pronged arm portion 11 of the clip unit 8. This removes the four-pronged arm portion 11. reserve The restorative force causes it to open and face the area in close proximity to the affected area within the digestive tract.

[0060] Next, as shown in Figure 9(A), the slightly open first and second arm legs 12 and 13 are advanced and brought into contact with one wall of the affected area, and then, as shown in Figure 9(B), the slider 2b of the operating unit 2 is operated to advance relative to the cylindrical shaft 2a, thereby moving the inner sheath 4 forward by the required distance, moving the tightening ring 30 from the initial fitted position A to the first tightening position B, which tightens the first spreading portions 12b and 13b of the first and second arm legs 12 and 13. As a result, the first gripping portions 12c and 13c of the first and second arm legs 12 and 13 close together and grip one wall of the affected area. At this time, the claws 16 and 17 at the tips of the first and second arm legs 12 and 13 bite into one wall from both sides, so that one wall of the affected area does not slip away from the first gripping portions 12c and 13c.

[0061] Next, for example, by tilting the axis of the clip unit 8, one wall of the affected area clamped by the first clamping parts 12c and 13c is brought closer to the other wall, as shown in Figure 9(C). The first and second arm legs 12 and 13 and the third and fourth arm legs 14 and 15 open independently from a single base end and are configured to be tightened according to the tightening position of the tightening ring 30. Therefore, when the first and second arm legs 12 and 13 are closed, the open state of the third and fourth arm legs 14 and 15 is not narrowed to some extent.

[0062] Next, in order to close the widely open third and fourth arm legs 14 and 15, the slider 2b of the operating unit 2 shown in Figure 1 is operated to retract further relative to the cylindrical shaft 2a, and the inner sheath 4 is moved further forward by the required distance. As a result, as shown in Figure 8(A), the tightening ring 30 can be moved through the intermediate position where it tightens the second spreading portions 14b and 15b of the third and fourth arm legs 14 and 15, and then to the second tightening position C where it tightens the second clamping portions 14c and 15c. As a result, as shown in Figure 9(D), the claws 18 and 19 bite into the parts on both sides that sandwich both walls of the affected area, and the second clamping portions 14c and 15c can clamp the parts on both sides together, so that the two walls of the wide-open wound can be closed. If the state in which the two walls of the wound are closed is maintained for a certain period of time, the two walls of the wound can be joined together.

[0063] After the procedure is complete, the clip unit 8 is left in the body cavity. Therefore, after the procedure is complete, the knob 5a of the operating part 2 shown in Figure 1 is moved in the proximal direction relative to the cylindrical shaft 2a, thereby moving the inner sheath 4 to a position where it does not cover the release mechanism 7, as shown in Figure 8(B). This causes the release mechanism 7 to elastically return to an open position, releasing the chuck. Next, by pulling the finger ring 2c in the proximal direction, the ligation device 1 separates from the clip unit 8, and the clip unit 8 can be left in the body cavity in the state shown in Figures 4(D), 5(D), and 9(D).

[0064] As described above, the clip unit for a ligation device according to the present invention has two pairs of openable and closable first to fourth arm legs 12-15 and a four-pronged structure that allows the two pairs of first to fourth arm legs 12-15 to be closed in stages by moving the tightening ring in two stages. The clip unit 8 for a ligation device can be provided that can grasp one wall surface of a widely opened wound (affected area) with a pair of first and second arm legs 12,13, bring one wall surface closer to the other wall surface, and then bring both sides of the joined opposing holes together with another pair of third and fourth arm legs 14,15 to securely close the wound and leave it in the body cavity. Furthermore, the clip unit 8 for a ligation device can be provided that is easy to manufacture by a combination of press working and laser welding and does not reduce the spring opening and closing performance. [Explanation of symbols]

[0065] 1...Ligation device 2...Operation unit 2a...Cylinder shaft part 2a1... Slit 2b... Slider 2b1…Diameter connection part 2b2…Finger rest part 2c... Finger loop ring 3a...Male cylindrical connecting part 3b…Female cylindrical connection part 4…Inner sheath 4a... Inner sheath body 4b…Holding cylinder 4b1...Tightening ring housing 4b2...Chuck tightening part 5…Outer sheath 5a...Pickling part 6…Operating wire 7... Connector release tool 7a, 7b... Chuck jaws 8…Clip unit for ligation device 8a...Clip unit body 10…Proximal connection part 10a...end face part 10b,10b…Side part 11... Sumo-arm section 12...First Arm Leg 12a...Proximal end 12b...First widening section (inclined widening section) 12c...First clamping part (tip portion) 13...Second Arm Leg 13a...Proximal end 13b...First widening section (inclined widening section) 13c...First clamping part (tip portion) 14…Third Arm Leg 14a...Proximal end 14b...Second expansion 14c...Second clamping part (tip portion) 15…Fourth Arm Leg 15a...Proximal end 15b...Second expansion 15c...Second clamping part (tip portion) 16, 17… Nails 18, 19… Nails 20a, 20b…Protrusion 30...Tightening ring A…Initial fitting position B...First tightening position C...Second tightening position

Claims

1. A clip unit for a ligation device, which is detachably attached to the tip of a ligation device inserted into a body cavity via an endoscope channel to grasp a lesion and perform hemostasis, and which is detached after the procedure and remains in the body, The ligation device has a base connecting portion that is chucked by a release tool connected to the tip of the operating wire of the ligation device, a four-pronged arm portion having first to fourth arm legs that extend elastically from the base connecting portion and each arm leg tip having a claw, and a tightening ring that is fitted onto the base end side of the four-pronged arm portion and is provided to be slidable toward the tip by operation of the ligation device, The four-pronged arm section includes first and second arm legs that begin to spread midway and increase the accumulated recovery force that causes the bifurcated tip, which is spaced further apart than the first and second arm legs, to expand in the opening direction in response to a tightening force in the closing direction, and third and fourth arm legs that begin to spread midway further ahead than the first and second arm legs and increase the accumulated recovery force that causes the bifurcated tip, which is spaced further apart than the first and second arm legs, to expand in the opening direction in response to a tightening force in the closing direction. The base end of the first arm leg and the base end of the third arm leg are aligned side by side, and the base end of the second arm leg and the base end of the fourth arm leg are aligned side by side, and the initial fitted position is when the four corners of the cross-section of the base ends of the first to fourth arm legs of the clamping ring abut against the inner circumferential surface. The configuration is such that when the clamping ring moves to a first clamping position a required distance away from the initial fitting position in the direction of the tip, the tip portions of the first and second arm legs close together, and when the clamping ring moves to a second clamping position a required distance away in the direction of the tip, the tip portions of the first to fourth arm legs close together. A clip unit for a ligation device characterized by the following features.

2. The first and second arm legs each include a base end portion that extends integrally from the base end connecting portion and is the initial fitting position of the clamping ring, a first widening portion that extends in an inclined manner in the middle portion, and a first clamping portion that extends substantially parallel to each other at the tip portion. The third and fourth arm legs are configured to include a base end portion that extends integrally from the base end connecting portion and is the initial fitting position of the clamping ring, a second widening portion that is an intermediate portion that curves and extends outward, and a second clamping portion that is a tip portion and has a predetermined intersection angle so as to gradually open outward toward the tip. A clip unit for a ligation device according to claim 1.

3. When the clamping ring moves from the initial fitted position to a first clamping position a required distance away in the direction of the tip, the clamping ring tightens the first spreading portion in the middle of the first and second arm legs, causing the first clamping portion at the tip to close together. Furthermore, when the clamping ring moves to a second clamping position a required distance away in the direction of the tip, the clamping ring tightens the second spreading portion in the middle of the third and fourth arm legs, and then tightens the second clamping portion at the tip, causing the second clamping portions of the third and fourth arm legs to close together. A clip unit for a ligation device according to claim 2.

4. The pair of claws at the tips of the first and second arm legs are oriented toward the opening / closing center, When the tip ends of the first and second arm legs are closed together, they overlap front to back. The pair of claws at the tips of the third and fourth arm legs are oriented toward the opening / closing center, The configuration is such that when the tip ends of the first and second arm legs are closed together, they overlap front to back. A clip unit for a ligation device according to claim 1.

5. The vicinity of the tips of the first and second arm legs, and the claws extending from the vicinity of said tips, are formed to be wide and extend in the opposite direction from the third and fourth arm legs in the plate width direction. The vicinity of the tips of the third and fourth arm legs, and the claws extending from said vicinity of the tips, are formed to be wider and extend in the opposite direction from the first and second arm legs in the plate width direction. A clip unit for a ligation device according to any one of claims 1 to 4.

6. The clip unit for a ligating device according to any one of claims 1 to 4, wherein the four-pronged arm portion has a plurality of projections that the tightening ring can overcome and that contact the tightening ring to prevent it from moving toward the base end, in each of the following positions: an initial fitting position in which the tightening ring is fitted onto the base end side of the first to fourth arm legs; a first tightening position of the tightening ring when the pair of first clamping portions of the first and second arm legs are closed together; and a second tightening position of the tightening ring when the pair of second clamping portions of the third and fourth arm legs of the tightening ring are closed together.

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