Bracket assembly for medical instrument, treatment instrument for endoscope, and method for assembling bracket assembly for medical instrument

Abstract

This bracket assembly for a medical instrument includes a bracket having a base end part and a plurality of arms extending from the base end part, a shaft extending between the plurality of arms, and a pair of pieces supported by the shaft between the plurality of arms, wherein the plurality of arms is fixed to the shaft in a state of being elastically deformed in a direction approaching the pair of pieces.

Description

Bracket assembly for medical instrument, treatment instrument for endoscope, and method for assembling bracket assembly for medical instrument

[0001] The present disclosure relates to a bracket assembly for a medical instrument, a treatment instrument for an endoscope, and a method for assembling a bracket assembly for a medical instrument.

[0002] Conventionally, in endoscopic treatment, treatment instruments for endoscopes in which a treatment portion such as forceps provided at a distal end rotates have been used (for example, Patent Document 1 and Patent Document 2). The treatment portion such as forceps is rotatably supported by a bracket or the like.

[0003] U.S. Patent No. 7534253 U.S. Patent Application Publication No. 2022 / 0395287

[0004] It is desirable that the pair of pieces constituting the treatment portion such as forceps do not make the bracket too close to the pair of pieces so that the pair of pieces can easily rotate relative to the bracket. On the other hand, if an excessive gap is generated between the pair of pieces and the bracket, the operation of the treatment portion may not be stable, such as misalignment of the forceps cups.

[0005] In view of the above circumstances, an object of the present disclosure is to provide a bracket assembly for a medical instrument, a treatment instrument for an endoscope, and a method for assembling a bracket assembly for a medical instrument, in which the pair of pieces can easily rotate, and the treatment portion can stably perform a desired operation at low cost.

[0006] To solve the above problems, the present disclosure proposes the following means. A bracket assembly for a medical instrument according to a first aspect of the present disclosure includes: a bracket having a base end portion and a plurality of arms extending from the base end portion; a shaft extending between the plurality of arms; and a pair of pieces supported by the shaft between the plurality of arms, wherein the plurality of arms are fixed to the shaft in a state of being elastically deformed in a direction approaching the pair of pieces.

[0007] The bracket assembly for a medical instrument, the treatment instrument for an endoscope, and the method for assembling a bracket assembly for a medical instrument according to the present disclosure allow the rotatable treatment portion to easily rotate and be less likely to tilt in the rotation axis direction.

[0008] An overall view of the endoscopic treatment system according to the first embodiment. An overall view showing the treatment instrument of the endoscopic treatment system. A perspective view of the tip of the treatment instrument. A side view of the tip of the treatment instrument. A cross-sectional view of the tip of the treatment instrument. A cross-sectional view of the sheath and transmission member of the treatment instrument. A diagram showing the wire of the transmission member. A plan view of the tip of the treatment instrument. A cross-sectional view of the tip of the treatment instrument. A diagram showing the operation of the link mechanism. Same as above. Same as above. Same as above. A diagram showing the assembly method of the bracket assembly. Same as above. Same as above. Same as above. Same as above. A cross-sectional view showing the first and second arms in a different embodiment before assembly. A cross-sectional view showing the first and second arms in a different embodiment after assembly. A diagram showing a modified counterbore. A cross-sectional view showing the first and second arms in a different embodiment after assembly. A cross-sectional view showing a modified pin. A cross-sectional view showing another modified pin. A cross-sectional view showing another modified pin. A cross-sectional view showing another modified pin. A cross-sectional view showing another modified pin. A perspective view of the operating part of the treatment instrument. A cross-sectional view of the operating part. A diagram showing the handle body of the operating part. Same as above. Same as above. A diagram showing a modified example of the plug socket of the handle body. Same as above. Same as above. A diagram showing a modified example of the first arm. A perspective view of the tip of the treatment tool according to the second embodiment. A plan view of the tip of the treatment tool. A diagram showing a modified example of the first arm of the treatment tool.

[0009] (First Embodiment) An endoscopic treatment system 300 equipped with an endoscopic treatment instrument 100 according to the first embodiment of this disclosure will be described with reference to Figures 1 to 33. Figure 1 is an overall view of the endoscopic treatment system 300.

[0010] [Endoscopic Treatment System 300] As shown in Figure 1, the endoscopic treatment system 300 comprises an endoscopic treatment instrument 100 and an endoscope 200. The endoscopic treatment instrument 100 is used by being inserted into the endoscope 200.

[0011] [Endoscope 200] The endoscope 200 is a known flexible endoscope and comprises an insertion section 210 that is inserted into the body from the tip, an operating section 220 attached to the base end of the insertion section 210, and a universal cord 230 attached to the operating section 220.

[0012] The insertion portion 210 is an elongated, slender member that can be inserted into the lumen. The insertion portion 210 has a tip portion 211, a curved portion 214, and a flexible portion 215. The tip portion 211, the curved portion 214, and the flexible portion 215 are connected in order from the tip side. Inside the insertion portion 210, there is a channel 216 for inserting the endoscopic treatment instrument 100. The tip portion 211 is provided with a tip opening 212 of the channel 216 and an imaging portion 213.

[0013] The imaging unit 213 is equipped with an image sensor such as a CCD or CMOS, and is capable of imaging the area to be treated. The curved unit 214 bends according to the operation of the operating unit 220 by the user. The flexible unit 215 is a flexible, tubular part.

[0014] The operating section 220 is connected to the flexible section 215. The operating section 220 has a grip 221, an input section 222, and a forceps opening 223. The grip 221 is a member supported by the user. The input section 222 receives an input for bending the bending section 214. The forceps opening 223 is the base end opening of the channel 216.

[0015] The universal cord 230 connects the endoscopic treatment instrument 100 to external equipment. The universal cord 230 contains an imaging cable, optical fiber cable, etc., which outputs the imaging signal captured by the imaging unit 213 to the outside.

[0016] [Endoscopic Treatment Instrument 100] Figure 2 is an overall view of the endoscopic treatment instrument 100. The endoscopic treatment instrument 100 (also called treatment instrument 100) is a hemostatic forceps used to cauterize the affected area and stop bleeding. The treatment instrument 100 comprises a sheath 1, a transmission member 2 (see Figure 5), a support member 3, forceps (jaws) 4, and an operating part 5. In the following description, in the longitudinal axis direction (longitudinal direction, axial direction) A of the treatment instrument 100, the side inserted into the patient's body is referred to as the "tip side (distal side) A1," and the side with the operating part 5 is referred to as the "proximal side (proximal side) A2."

[0017] Figure 3 is a perspective view of the tip of the treatment instrument 100. The tip of the treatment instrument 100 is provided with a support member 3 and forceps 4. The forceps (jaws) 4 are rotatably supported by the support member 3. The support member 3 and forceps 4 constitute the "treatment section (end effector) 110" for treating the affected area. In this embodiment, the treatment section 110 is a hemostatic forceps, but the treatment section is not limited to this. The treatment section may be a biopsy forceps, a high-frequency knife, a needle holder, etc.

[0018] In the following explanation, the direction in which the forceps 4 opens and closes will be referred to as "opening / closing direction B" or "up / down direction B". The direction perpendicular to the longitudinal direction A and the opening / closing direction B will be referred to as "width direction C" or "left / right direction C". The plane horizontal to the longitudinal direction A and the width direction C will be referred to as "horizontal plane HP". The plane horizontal to the longitudinal direction A and the opening / closing direction B will be referred to as "vertical plane VP".

[0019] The sheath 1 is a flexible, elongated member extending from a tip 1a to a base 1b. The sheath 1 is insertable into the channel 216 of the endoscope 200. As shown in Figure 1, when the sheath 1 is inserted into the channel 216, the tip 1a of the sheath 1 can protrude from the tip opening 212 of the channel 216. The base 1b of the sheath 1 is connected to the operating section 5. The sheath 1 may also be insulating.

[0020] Figure 4 is a side view of the tip of the treatment instrument 100. Figure 5 is a cross-sectional view of the tip of the treatment instrument 100. The sheath 1 comprises a coil sheath 11 formed by spirally winding metal wires, and a covering tube 12 that covers the outer surface of the coil sheath 11. The coil sheath 11 may be formed from a round wire coil (see Figure 5) or from a flat wire coil (see Figure 6). The covering tube 12 is, for example, a heat-shrinkable tube made of resin.

[0021] Figure 6 is a cross-sectional view of the sheath 1 and the transmission member 2. By using a flat wire coil in the coil sheath 11, the wall thickness Tco is reduced, and the maximum outer diameter Td of the sheath 1 is made smaller. This ensures sufficient space between the endoscope channel and the sheath 1, thereby improving the suction effect using the channel.

[0022] The transmission member (wire) 2 is inserted through the internal space 1s of the coil sheath 11. The tip of the transmission member 2 is connected to the forceps 4 via a connector 39 or the like. The base end of the transmission member 2 is connected to the operating part 5. The transmission member 2 has a metal wire 21, a pipe 22, and an inner tube 23.

[0023] Figure 7 shows the wire 21. The wire 21 is conductive and transmits high-frequency current to the forceps 4. The wire 21 is formed by twisting together multiple strands. The outer diameter D1 of the central strand is larger than the outer diameter D2 of the surrounding strands. The base end of the wire 21 is inserted into the pipe 22 (see Figure 26) in the operating section 5. Note that the wire 21 is not limited to stranded wire, but can be any conductive material such as a metal coil tube.

[0024] As shown in Figure 6, the inner tube 23 is positioned around the outer circumference of the wire 21. At least a portion of the wire 21 passes through the inner tube 23. The inner tube 23 is not fixed to the wire 21.

[0025] Figure 8 is a plan view of the tip of the treatment instrument 100. Figure 9 is a cross-sectional view of the tip of the treatment instrument 100. The support member 3 is attached to the tip 1a of the sheath 1 and rotatably supports the forceps 4. The support member 3 comprises a bracket 31, a pin 36, a link mechanism 37, a sheath connector 38, and a connector 39. The forceps 4 is supported by the pin 36 attached to the bracket 31.

[0026] The bracket 31 is formed in a roughly U-shape from a metal such as stainless steel. Note that "roughly U-shape" includes not only a strictly U-shape but also a shape that is close to a U-shape. The bracket 31 is formed by machining. The bracket 31 has a cylindrical support body 32 and a pair of arms 33 (first arm 34 and second arm 35).

[0027] The support body (base end) 32 is supported on the tip 1a of the sheath 1 so as to be rotatable around the longitudinal axis of the sheath 1. The central axis O3 of the support member 3 in the longitudinal direction A substantially coincides with the central axis O1 of the sheath 1 in the longitudinal direction A. Note that "substantially coincides" includes not only strictly coincident forms but also forms that are almost coincident. The internal space 3s of the support body 32 is in communication with the internal space 1s of the sheath 1. The transmission member 2 and the connector 39 are inserted through the internal space 3s of the support body 32.

[0028] A pair of arms 33 (first arm 34 and second arm 35) extend from the support body 32 to the tip side A1. The first arm 34 and the second arm 35 are provided evenly on both sides in the width direction C, with the central axis O3 in between. Note that the first arm 34 and the second arm 35 do not necessarily need to be provided evenly and can be changed as appropriate depending on the structure of the link mechanism. The first arm 34 and the second arm 35 have a symmetrical shape with respect to the vertical plane VP passing through the central axis O3.

[0029] The first arm 34 is formed in a flat plate shape extending in the longitudinal direction A. The thickness direction of the first arm 34 is approximately the same as the width direction C. Note that "approximately the same" includes not only strictly the same but also nearly the same. The base end A2 of the first arm 34 is connected to the support body 32.

[0030] A first through-hole 34h is formed at the tip side A1 of the first arm 34, penetrating in the thickness direction. The first through-hole 34h opens outward (outer surface 34e) in the width direction C of the first arm 34. The first through-hole 34h also opens inward (inner surface 34i) in the width direction C of the first arm 34.

[0031] In the first through hole 34h, a counterbore (recess) 34c is formed on the outside in the width direction C, which has a larger outer diameter than the rest of the first through hole 34h (see Figure 14). The counterbore (recess) 34c has a vertical surface VP and a substantially horizontal bottom surface 34s.

[0032] The second arm 35 is formed in a flat plate shape extending in the longitudinal direction A. The thickness direction of the second arm 35 is approximately the same as the width direction C. Note that "approximately the same" includes not only strictly the same but also nearly the same. The base end A2 of the second arm 35 is connected to the support body 32.

[0033] A second through-hole 35h is formed at the tip side A1 of the second arm 35, penetrating in the thickness direction. The second through-hole 35h opens outward (outer surface 35e) in the width direction C of the second arm 35. The second through-hole 35h also opens inward (inner surface 35i) in the width direction C of the second arm 35.

[0034] As shown in Figure 9, the pin (shaft, rotational shaft, rotational shaft member) 36 is formed in a substantially cylindrical shape from a metal such as stainless steel. The pin 36 is attached to the bracket 31 by engaging with the first through hole 34h and the second through hole 35h. The longitudinal axis direction of the pin 36 substantially coincides with the width direction C. Note that "substantially coincides" includes not only strictly coincident configurations but also configurations that are almost coincident. The pin 36 has a main cylindrical portion 36d and a flared portion 36f.

[0035] One end of the pin 36, the first end 36a, is inserted through the first through hole 34h of the first arm 34 and engages with the first through hole 34h to attach it to the bracket 31. The other end of the pin 36, the second end 36b, is inserted through the second through hole 35h of the second arm 35 and engages with the second through hole 35h to attach it to the bracket 31. The end of the first end 36a is provided with a flared portion 36f that locks onto the first arm 34. Specifically, the flared portion 36f is a flange and has a larger outer diameter than the main cylindrical portion 36d of the pin 36.

[0036] Figures 10 to 13 illustrate the operation of the link mechanism 37. The link mechanism 37 is a link mechanism that converts the forward and backward movement of the transmission member 2 in the longitudinal direction A into the opening and closing movement of the forceps 4. The link mechanism 37 has a first link 37b and a second link 37c. In Figures 10 and 11, the link mechanism 37 is closing the forceps 4. In Figures 12 and 13, the link mechanism 37 is opening the forceps 4.

[0037] The first link 37b is a plate-shaped member that connects the connector 39 to the first forceps piece 41 of the forceps 4. The first link 37b is connected to the connector 39 via a pin 37p so as to be rotatable along the plane VP perpendicular to the connector 39. The first link 37b is also connected to the first forceps piece 41 so as to be rotatable along the plane VP perpendicular to the first forceps piece 41.

[0038] The second link 37c is a plate-shaped member that connects the connector 39 to the second forceps piece 42 of the forceps 4. The second link 37c is connected to the connector 39 via a pin 37p so as to be rotatable along the plane VP perpendicular to the connector 39. The second link 37c is also connected to the second forceps piece 42 so as to be rotatable along the plane VP perpendicular to the second forceps piece 42.

[0039] The sheath connector 38 connects the tip 1a of the sheath 1 to the support body 32. The base end of the sheath connector 38 is welded to the coil sheath 11 of the sheath 1. The tip of the sheath connector 38 is attached to the sheath connector holder 38a. The sheath connector 38 and the sheath connector holder 38a are configured to rotate on the support body 32 with a central axis O3 as the center of rotation.

[0040] The connector 39 is formed in a cylindrical shape and is inserted into the internal space 3s of the support body 32. The connector 39 can move back and forth along the longitudinal direction A. The tip of the wire 21 is attached to the base end A2 of the connector 39 by welding or the like.

[0041] The wire 21 may be directly connected to the base end of the connector 39, or it may be connected via a connecting member (not shown).

[0042] When the wire 21 rotates around the central axis O3, the welded connector 39, link mechanism 37, pin 36, bracket 31, and sheath connector holder 38a rotate in conjunction. On the other hand, the coil sheath 11 and sheath connector 38 do not rotate. In other words, when the wire 21 rotates around its longitudinal axis, the connector 39, link mechanism 37, pin 36, bracket 31, and sheath connector holder 38a are configured to rotate relative to the coil sheath 11 and sheath connector 38.

[0043] A gap between the proximal end of the connector 39 and the sheath connector 38 is defined as a first clearance CA, a gap between the connector 39 and the pair of arms 33 is defined as a second clearance CB, a gap between the connector 39 and the sheath connector 38 is defined as a third clearance CC, a gap between the sheath connector 38 and the support main body 32 is defined as a fourth clearance CD, and a gap between the sheath connector holder 38a and the support main body 32 is defined as a fifth clearance CE.

[0044] It is necessary to secure a gap for welding the wire 21 and the connector 39, but when this gap is large, single-sided opening of the forceps 4 is likely to occur. Therefore, it is desirable that the first clearance CA is larger than the second clearance CB, the third clearance CC, and the fifth clearance CE. It is desirable that the second clearance CB, the third clearance CC, and the fifth clearance CE are smaller than the fourth clearance CD.

[0045] The forceps (jaws) 4 is a member for grasping a living tissue. The forceps 4 is supported by the support member 3 so as to be openable and closable toward the distal side A1. The forceps 4 is formed of a metal material such as stainless steel, and includes a first forceps piece 41 and a second forceps piece 42.

[0046] The first forceps piece 41 and the second forceps piece 42 are arranged so as to be symmetrical with respect to the central axis O4 in the longitudinal direction A of the forceps 4. The central axis O4 in the longitudinal direction A of the forceps 4 substantially coincides with the central axis O1 in the longitudinal direction A of the sheath 1. The term "substantially coincides" includes not only a strictly coinciding aspect but also a nearly coinciding aspect.

[0047] In the following description, the direction in which the first forceps piece 41 opens is defined as "lower side B1" in the opening / closing direction B, and the direction in which the second forceps piece 42 opens is defined as "upper side B2" in the opening / closing direction B. Further, the direction facing right when viewing from the distal side A1 to the proximal side A2 is defined as "right side C1" in the width direction C, and the direction facing left is defined as "left side C2" in the width direction C.

[0048] The first forceps piece 41 is rotatably supported by the pin 36 about the central axis R of the pin 36 as the rotation center. The first forceps piece 41 has a first cup 41c provided on the distal end side A1, a first edge 41e, and a first plate 41p.

[0049] The first cup 41c is formed in a cup shape and opens toward the second forceps piece 42 side (upper side B2) in the opening and closing direction B.

[0050] The first edge 41e is the opening edge of the first cup 41c. The first edge 41e has a first serrated portion 41t. The first serrated portion 41t is a serrated unevenness provided on the first edge 41e.

[0051] As shown in FIG. 9, the first plate (left plate, left piece) 41p is provided on the proximal end side A2 of the first cup 41c and is formed in a substantially plate shape. The term "substantially plate-shaped" includes not only a strict plate shape but also a shape close to a plate shape. The plate thickness direction of the first plate 41p substantially coincides with the width direction C. The term "substantially coincides" includes not only the aspect of strict coincidence but also the aspect of almost coincidence. The first plate 41p is provided with a through hole 41h through which the pin 36 extends in the width direction C.

[0052] The second forceps piece 42 is rotatably supported by the pin 36 about the central axis R of the pin 36 as the rotation center. The second forceps piece 42 has a second cup 42c provided on the distal end side A1, a second edge 42e, and a second plate 42p.

[0053] The second cup 42c is formed in a cup shape and opens toward the first forceps piece 41 side (lower side B1) in the opening and closing direction B.

[0054] The second edge 42e is the opening edge of the second cup 42c. The second edge 42e has a second serrated portion 42t. The second serrated portion 42t is a serrated unevenness provided on the second edge 42e.

[0055] As shown in Figure 9, the second plate (right plate, right piece) 42p is provided on the base end side A2 of the second cup 42c and is formed in a substantially plate shape. The thickness direction of the second plate 42p substantially coincides with the width direction C. Note that "substantially coincides" includes not only strictly coincident forms but also forms that are almost coincident. The second plate 42p is provided with a through hole 42h through which the pin 36 extends in the width direction C.

[0056] The first plate 41p and the second plate 42p are arranged adjacent to each other in the left-right direction C. The first plate 41p and the second plate 42p are supported by a through pin 36. The first plate 41p and the second plate 42p supported by the pin 36 are also called a "pair of plates (pair of pieces) 4P".

[0057] In addition, one of the first forceps piece 41 and the second forceps piece 42 may be fixed to the support member 3, while the other may be rotatably supported by the support member 3.

[0058] The bracket 31, pin 36, and pair of plates 4P that support the first forceps piece 41 and the second forceps piece 42 so that they can be opened and closed are also referred to as the "bracket assembly 120".

[0059] [Assembly Method of Bracket Assembly 120] Figures 14 to 18 show the assembly method of the bracket assembly 120. The assembly method of the bracket assembly 120 will be described below.

[0060] As shown in Figures 14 and 15, the operator inserts the pin 36 from its first end 36a into the first through-hole 34h of the first arm 34. The pin 36 is then inserted into the second through-hole 35h of the second arm 35 via the through-hole 42h of the second forceps piece 42 and the through-hole 41h of the first forceps piece 41.

[0061] The length L1 of the flared portion 36f of the pin 36 in the width direction C is longer than the length L2 of the counterbore 34c in the width direction C in the first through hole 34h (L1 > L2). Therefore, as shown in Figure 15, the flared portion 36f can be housed in the counterbore 34c without protruding from the counterbore 34c in the width direction C.

[0062] As shown in Figure 15, the worker aligns the flared portion 36f provided on the first end 36a of the pin 36 with the outer surface 34e of the first arm 34. At that time, a gap L3 is formed in the width direction C between the flared portion 36f and the bottom surface 34s of the counterbore (recess) 34c (L3 ≠ 0).

[0063] As shown in Figure 16, the jig J presses the outer surface 34e of the first arm 34 against the outer surface 35e of the second arm 35, causing the first arm 34 and the second arm 35 to elastically deform in a direction that brings them closer to the pair of plates 4P. The jig J causes the first arm 34 and the second arm 35 to elastically deform while the flared portion 36f provided on the first end 36a of the pin 36 is aligned with the outer surface 34e of the first arm 34.

[0064] As shown in Figure 17, the worker fixes the second end portion 36b to the second through-hole 35h of the second arm 35 by laser welding through the opening JO provided in the jig J. The second end portion 36b is fixed to the second through-hole 35h. When laser welding, in order to ensure welding strength, the inner surface of the second through-hole 35h may be pressed against the tip or base end of the sheath 1 with respect to the pin 36 while welding. Furthermore, the method is not limited to this, and known welding techniques for ensuring welding strength can be used.

[0065] The second end portion 36b may be fixed to the second through hole 35h of the second arm 35 by a method other than welding. For example, the second end portion 36b may be fixed to the second through hole 35h by joining such as crimping, bolting, or press-fitting.

[0066] As shown in Figure 18, the operator releases the jig J from the first arm 34 and the second arm 35, thereby locking the flared portion 36f against the bottom surface 34s of the counterbore 34c. The gap in the width direction C between the flared portion 36f and the bottom surface 34s of the counterbore 34c is eliminated.

[0067] The distance L7 between the tip of the first arm 34 and the tip of the second arm 35 after assembly is shorter than the distance L4 between the tip of the first arm 34 and the tip of the second arm 35 before assembly (see Figure 14) (L4 > L7). In other words, the clearance between the first arm 34 and the second arm 35 and the pair of plates 4P becomes smaller. As a result, the surfaces of the pair of plates 4P facing the width direction C (the surfaces facing the first arm 34 and the second arm 35) are fixed to the bracket 31 in such a way that they are less likely to tilt with respect to the longitudinal axis direction A of the sheath 1.

[0068] The difference between distance L7 and distance L4 is approximately equal to the gap L3 (L4 - L7 ≈ L3). Note that "approximately equal" includes not only the case where they are exactly the same, but also the case where they are almost the same. By adjusting the gap L3 by changing the length of the width direction C in the flared portion 36f of the pin 36, the clearance between the first arm 34 and the second arm 35 and the pair of plates 4P after assembly can be easily adjusted. The operator adjusts the gap L3 so that the openable and closable forceps 4 can rotate easily.

[0069] The clearance between the first arm 34 and the second arm 35 and the pair of plates 4P after assembly is preferably 0.01 to 0.09 mm, and more preferably 0.005 to 0.1 mm. If the clearance is less than 0.005 mm, the movement of the forceps 4 becomes sluggish, and if the clearance exceeds 0.1 mm, the cup misalignment becomes about 0.2 mm, which is a misalignment that cannot be ignored in treatment. Here, cup misalignment refers to the displacement of the first edge 41e of the first cup 41c and the second edge 42e of the second cup 42c when the forceps 4 is closed. Specifically, if the clearance exceeds 0.1 mm, the operator is more likely to feel discomfort when grasping tissue. For example, if the treatment section 110 is a hemostatic forceps as in this embodiment, it will affect the hemostatic performance during hemostasis.

[0070] As shown in Figure 14, assume that the distance L4 between the tip of the first arm 34 and the tip of the second arm 35 before assembly is approximately the same as the distance L6 between the base of the first arm 34 and the base of the second arm 35 before assembly (L4 ≈ L6). In this case, the distance L7 between the tip of the first arm 34 and the tip of the second arm 35 after assembly is shorter than the distance L9 between the base of the first arm 34 and the base of the second arm 35 after assembly (L9 > L7). The inner surfaces 34i of the first arm 34 and 35i of the second arm 35 are inclined in a direction that brings them closer to each other from the base to the tip. If the length C in the width direction of the first arm 34 and the second arm 35 is uniform along the longitudinal direction A, then the outer surfaces 34e of the first arm 34 and 35e of the second arm 35 are also inclined in a direction that brings them closer to each other from the base to the tip.

[0071] Figure 19 is a cross-sectional view showing the first arm 34 and the second arm 35 in another configuration before assembly. Figure 20 is a cross-sectional view showing the first arm 34 and the second arm 35 in another configuration after assembly. As shown in Figure 19, the distance L4 between the tip of the first arm 34 and the tip of the second arm 35 before assembly is assumed to be greater than the distance L6 between the base of the first arm 34 and the base of the second arm 35 before assembly (L4 > L6). In this case, as shown in Figure 20, the distance L7 between the tip of the first arm 34 and the tip of the second arm 35 after assembly may be approximately equal to the distance L9 between the base of the first arm 34 and the base of the second arm 35 after assembly (L9 ≈ L7). The inner surfaces 34i of the first arm 34 and 35i of the second arm 35 are arranged in parallel.

[0072] In the width direction C (the longitudinal axis direction of the pin 36 and the rotation axis direction), the width L8 of the pair of plates 4P after assembly is smaller than the width L5 of the pair of plates 4P before assembly (L5 > L8). In the width direction C (the longitudinal axis direction of the pin 36), the width L8 of the pair of plates after assembly is smaller than the distance L9 between the base end of the first arm 34 and the base end of the second arm 35 after assembly (L9 > L8).

[0073] Figure 21 shows a recess JC, which is a modified example of the counterbore 34c. Figure 22 is a cross-sectional view showing the first arm 34 and second arm 35 in another configuration after assembly. The jig J may have a recess JC. The recess JC is provided in the jig J at the location where the flared portion 36f of the pin 36 is pressed in. The recess JC can accommodate the flared portion 36f so that it can move back and forth in the width direction C (the longitudinal axis direction and the rotation axis direction of the pin 36). By moving the flared portion 36f back and forth in the width direction C, the clearance between the first arm 34 and second arm 35 and the pair of plates 4P after assembly can be adjusted.

[0074] Figure 23 is a cross-sectional view showing a modified pin 36A of pin 36. Pin 36A has a relief groove 36g in the cylindrical body portion 36d where it connects to the flared portion 36f. This makes it easier to machine the flared portion 36f into a flat surface and to bring the flared portion 36f into close contact with the bottom surface 34s of the counterbore 34c.

[0075] Figure 24 is a cross-sectional view showing a modified pin 36B of pin 36. Pin 36B has a relief groove 36k in the portion of the flared portion 36f that connects to the main cylindrical portion 36d. This makes it easier to bring the flared portion 36f and the bottom surface 34s of the counterbore 34c into close contact.

[0076] Figure 25 is a cross-sectional view showing a modified pin 36C of pin 36. Pin 36C has a tapered flare portion 36Cf. In this case, the bottom surface 34s of the counterbore (recess) 34c is formed in a tapered shape so as to be able to contact the flare portion 36Cf.

[0077] Figure 26 is a cross-sectional view showing a modified pin 36D of pin 36. Pin 36D has a main body prism portion 36Dd whose cross-section perpendicular to the width direction C (the longitudinal axis direction and the rotation axis direction of pin 36) is polygonal.

[0078] Figure 27 is a cross-sectional view showing a modified pin 36E of pin 36. Pin 36E is formed by combining a separate main cylindrical portion 36Ed and a flared portion 36Ef.

[0079] Figure 28 is a perspective view of the operating section 5. Figure 29 is a cross-sectional view of the operating section 5. The operating section (handle, handle assembly) 5 is provided on the base end side A2 of the sheath 1, as shown in Figure 2. The operating section 5 comprises a handle body 6, an electrical connector 7, a slider 8, and a coil spring 9.

[0080] In the following description of the operating section 5, the direction in which the electrical connector 7 is provided relative to the handle body 6 will be referred to as "lower side B1" in the vertical direction B, and the opposite side of lower side B1 in the vertical direction B will be referred to as "upper side B2". Furthermore, the direction perpendicular to the longitudinal axis A and the vertical direction B will be referred to as "width direction C" or "left-right direction C". Looking from the tip side A1 to the base side A2, the direction to the right will be referred to as "right side C1" in the width direction C, and the direction to the left will be referred to as "left side C2" in the width direction C.

[0081] The handle body 6 has an internal space 6s through which the transmission member 2 can be inserted. The transmission member 2 extends to the slider 8, passing through the internal space 1 and the internal space 6s of the handle body 6. The handle body 6 includes a thumb ring 62, a connector support portion 64, and a coil sheath support portion 69.

[0082] The handle body 6 comprises a first handle body 60 and a second handle body 61. The second handle body 61 is connected to the base end of the first handle body 60. The first handle body 60 and the second handle body 61 are connected so as to be able to rotate relative to each other around a rotation axis extending in the longitudinal axis direction A. The internal space 6s is a continuous space formed in the first handle body 60 and the second handle body 61. The internal space 6s comprises an internal space 6t formed in the first handle body 60 and an internal space 6u formed in the second handle body 61.

[0083] The thumb ring 62 is provided on the proximal end A2 of the second handle body 61. The operator can support the second handle body 61 by inserting their thumb through the thumb ring 62.

[0084] The connector support portion 64 is provided on the first handle body 60. The connector support portion 64 supports the electrical connector 7. The connector support portion 64 has a through hole 65 that penetrates in the vertical direction and a cylindrical plug socket 66 formed on the lower side B1 of the through hole 65.

[0085] The through-hole 65 is a through-hole through which the reduced-diameter portion 75 of the electrical connector 7 is inserted. The vertical length of the through-hole 65 may be slightly shorter than the vertical length of the reduced-diameter portion 75.

[0086] The plug socket 66 is cylindrical in shape and surrounds the power plug 74 of the electrical connector 7. A gap is provided between the power plug 74 of the electrical connector 7 and the plug socket 66 for attaching the power cable (active cord).

[0087] Figures 30 to 32 show the handle body 6. The plug socket 66 has a slit 66s that extends in the vertical direction. The slit 66s is provided on the base end side A2 of the plug socket 66. Therefore, the plug socket 66 is easily bent in the width direction C.

[0088] The coil sheath support portion 69 supports the base end of the coil sheath 11 so that the base end of the coil sheath 11 is rotatable around its longitudinal axis but does not move forward or backward relative to the handle body 6 along the longitudinal axis A.

[0089] The electrical connector 7 is supported by the connector support portion 64 and is a conductive member that extends in a direction intersecting the longitudinal axis of the transmission member 2, and is formed in a substantially cylindrical shape. Note that "substantially cylindrical shape" includes not only a strictly cylindrical shape but also a shape that is close to a cylindrical shape.

[0090] The electrical connector 7 has an upper end portion 70, a connecting portion 71, a power supply plug 74, and a diameter-reducing portion 75. The electrical connector 7 extends between the power supply plug 74 and the upper end portion 70, which is supported by the coil spring support portion 67. The connecting portion 71 and the diameter-reducing portion 75 are located between the power supply plug 74 and the upper end portion 70. The upper end portion 70 is provided on the upper side B2 of the connecting portion 71. The direction in which the electrical connector 7 extends and the direction in which the transmission member 2 extends intersect.

[0091] The connecting portion 71 is formed in a substantially cylindrical shape and is provided on the upper side of the electrical connector 7. Note that "substantially cylindrical shape" includes not only a strictly cylindrical shape but also a shape that is close to a cylindrical shape. The connecting portion 71 is connected to the pipe 22 of the transmission member 2 in the internal space 6t of the first handle body 60. An insertion passage 72 is formed in the connecting portion 71. That is, an insertion passage 72 extending in the longitudinal axis direction A of the first handle body 60 is formed at the base end of the electrical connector 7.

[0092] The pipe 22 is inserted into the insertion passage 72. That is, the insertion passage 72 is a through hole formed along the longitudinal axis A from which the pipe 22 extends, and the pipe 22 and the wire 21 passing through the pipe 22 are inserted so as to be able to move back and forth.

[0093] The power supply plug 74 is a plug located on the lower side B1 of the electrical connector 7, to which the power cable (active cord) is connected. As shown in Figures 29 to 32, the power supply plug 74 has a slit 74s that extends in the vertical direction B. The slit 74s penetrates in the longitudinal direction A. Therefore, the power supply plug 74 is easily bent in the width direction C.

[0094] Therefore, even when the power cable (active cord) is inserted into the plug socket 66 at an angle relative to the vertical direction B, the direction in which the power cable is most likely to enter the plug socket 66 at an angle is different from the direction in which the power plug 74 is most likely to bend, thus preventing deformation of the power plug 74.

[0095] Figures 33 to 35 show a modified plug socket 66A, which is a modified version of the plug socket 66. The plug socket 66A has a slit 66As that extends in the vertical direction B. The slit 66As is provided on the right side C1 of the plug socket 66A. Therefore, the plug socket 66A is easily bent in the longitudinal direction A. In this case, the powered plug 74 is provided so that the slit 74s penetrates in the width direction C, making it easier to bend in the longitudinal direction A. This prevents deformation of the powered plug 74, as described above.

[0096] The diameter-reduced portion 75 is located in the middle of the vertical direction B and is provided between the insertion passage 72 and the power supply plug 74. The outer diameter of the diameter-reduced portion 75 is smaller than the outer diameter of the connecting portion 71 and the outer diameter of the power supply plug 74. The diameter-reduced portion 75 is inserted through the through hole 65 of the first handle body 60 and fixed in place.

[0097] The connecting portions 71 and the power plug 74, which are located on both sides of the reduced diameter portion 75 in the vertical direction B, cannot be inserted through the through hole 65 of the first handle body 60. By engaging the connecting portions 71 and the power plug 74 with the openings at both ends of the through hole 65 in the vertical direction B, the range of movement of the electrical connector 7 in the vertical direction B is restricted to a predetermined range.

[0098] The electrical connector (connecting member, plug) 7 can be connected to a high-frequency power supply unit (not shown) via a power cable, and the electrical connector 7, which is electrically and physically connected to the pipe 22 and wire 21, can supply high-frequency current supplied from the high-frequency power supply unit to the forceps 4 via the pipe 22 and wire 21.

[0099] Slider 8 is mounted along the second handle body 61 so as to be able to move back and forth in the longitudinal axis direction A. Slider 8 is able to move back and forth along the longitudinal axis relative to the second handle body 61. The base end of wire 21 and the base end of pipe 22 are connected to slider 8. When the operator moves slider 8 back and forth relative to the second handle body 61, wire 21 and pipe 22 move back and forth. When the operator rotates the second handle body 61 and slider 8 around the longitudinal axis relative to the first handle body 60, wire 21 and pipe 22 rotate. As a result, connector 39, link mechanism 37, pin 36, bracket 31 and sheath connector holder 38a are configured to rotate relative to coil sheath 11 and sheath connector 38.

[0100] The coil spring (elastic member, elastic body) 9 electrically connects the pipe 22, the wire 21, and the electrical connector 7 by applying a biasing force to the pipe 22. A part of the electrical connector 7 (connecting part 71) passes through the coil spring 9. The coil spring 9 is positioned in a compressed state, sandwiched between the pipe 22 and the electrical connector 7 in the internal space 6t of the handle body 6. The coil spring 9 is a conductive compression spring, and an elastic force acts in the direction that extends the electrical connector 7. Therefore, the coil spring 9 directly contacts the pipe 22 and presses the pipe 22 against the electrical connector 7. With the pipe 22 pressed against the electrical connector 7, the pipe 22 and the wire 21 can move forward and backward (slide) in the direction along the longitudinal axis of the pipe 22, and can also rotate (slide) in the circumferential direction relative to the longitudinal axis of the pipe 22.

[0101] The surgeon moves the forceps 4 forward or backward or rotates it by grasping the slider 8 and operating it to position the forceps 4 in the appropriate treatment position. Even when the slider 8 moves forward or backward relative to the second handle body 61 or when the second handle body 61 and slider 8 rotate relative to the first handle body 60, the coil spring 9 presses the pipe 22 against the electrical connector 7, thereby ensuring a reliable electrical connection between the pipe 22 and the wire 21 passing through the pipe 22 and the electrical connector 7.

[0102] The operator applies a high-frequency current to the wire 21 and pipe 22. Regardless of which direction perpendicular to the longitudinal axis A of the operating unit 5 is facing vertically downward, at least a portion of the insertion passage 72 is in electrically conductive contact with the pipe 22. Therefore, regardless of the orientation of the operating unit 5, a high-frequency current is supplied from the electrical connector 7 to the wire 21 and pipe 22, allowing the forceps 4 to perform procedures such as hemostasis and incision of the bleeding site.

[0103] According to the endoscopic treatment instrument 100 of this embodiment, the openable and closable forceps 4 are easy to open and close, and are less likely to tilt in the direction of the rotation axis.

[0104] Although the first embodiment of this disclosure has been described in detail above with reference to the drawings, the specific configuration is not limited to this embodiment and may include design changes and the like that do not depart from the gist of this disclosure. Furthermore, the components shown in the above-described embodiment and modifications can be combined as appropriate.

[0105] (Modification 1) Figure 36 shows a modified first arm 34A, which is a modified version of the first arm 34. A notch 34n communicating with the first through hole 34h is formed on the tip side A1 of the first arm 34A. The notch 34n penetrates the first arm 34 in the plate thickness direction. Because the notch 34n is formed on the first arm 34A, it is easy to engage the pin 36 with the first through hole 34h and the second through hole 35h when assembling the treatment section 110.

[0106] (Second Embodiment) The endoscopic treatment instrument 100B according to the second embodiment of the present disclosure will be described with reference to Figures 37 to 38. In the following description, components that are common to those already described will be denoted by the same reference numerals and redundant descriptions will be omitted.

[0107] Figure 37 is a perspective view of the tip of the treatment instrument 100B. The endoscopic treatment instrument 100B according to the first embodiment of the present disclosure comprises a sheath 1, a transmission member 2, a support member 3B, forceps (jaws) 4, and an operating section 5.

[0108] Figure 38 is a plan view of the tip of the treatment instrument 100B. The support member 3B is attached to the tip 1a of the sheath 1 and rotatably supports the forceps 4. The support member 3B comprises a bracket 31B, a pin 36, a link mechanism 37, and a connector 39. The forceps 4 is supported by the pin 36 attached to the bracket 31B.

[0109] Bracket 31B is formed in a roughly U-shape from a metal such as stainless steel. Note that "roughly U-shape" includes not only a strictly U-shape but also a shape that is close to a U-shape. Bracket 31B is formed by press working. Bracket 31B has a cylindrical support body 32B (base end of the first arm 34B and base end of the second arm 35B) and a pair of arms 33B (tip of the first arm 34B and tip of the second arm 35B).

[0110] The support body (base end) 32B is supported on the tip 1a of the sheath 1 so as to be rotatable around the longitudinal axis of the sheath 1. The base end of the first arm 34B and the base end of the second arm 35B are combined by a snap-fit ​​connection or the like to form the support body 32B.

[0111] The tips of the pair of arms 33B (first arm 34B and second arm 35B) extend from the support body 32B to the tip side A1. The tips of the first arm 34B and the second arm 35B are evenly spaced on both sides in the width direction C, straddling the central axis O3. Note that the tips of the first arm 34B and the second arm 35B do not necessarily have to be evenly spaced and can be changed as appropriate depending on the structure of the link mechanism. The first arm 34B and the second arm 35B are symmetrical in shape with respect to the vertical plane VP passing through the central axis O3.

[0112] The first arm 34B is formed in a flat plate shape extending in the longitudinal direction A. The thickness direction of the first arm 34B is approximately the same as the width direction C. Note that "approximately the same" includes not only strictly the same but also nearly the same. The first arm 34B has an inclined portion 34b that approaches the central axis O3 from the base end A2 to the tip end A1. A first through hole 34h is formed at the tip end A1 of the first arm 34B, penetrating in the thickness direction.

[0113] The second arm 35B is formed in a flat plate shape extending in the longitudinal direction A. The thickness direction of the second arm 35B is approximately the same as the width direction C. Note that "approximately the same" includes not only strictly the same but also nearly the same. The second arm 35B has an inclined portion 35b that approaches the central axis O3 from the base end A2 to the tip end A1. A second through hole 35h is formed at the tip end A1 of the second arm 35B, penetrating in the thickness direction.

[0114] In the first through hole 34h, a counterbore (recess) 34Bc is formed on the outer side in the width direction C, with an outer diameter larger than that of the rest of the first through hole 34h. The counterbore 34Bc is formed by press working. The pin 36 is fixed to the counterbore 34Bc by crimping.

[0115] According to the endoscopic treatment instrument 100B of this embodiment, the openable and closable forceps 4 are easy to open and close and are less likely to tilt in the direction of the rotation axis.

[0116] Although the second embodiment of this disclosure has been described in detail above with reference to the drawings, the specific configuration is not limited to this embodiment and may include design changes and the like that do not depart from the gist of this disclosure. Furthermore, the components shown in the above-described embodiment and modified examples can be combined as appropriate.

[0117] (Modification 2-1) Figure 39 shows a modification of the first arm 34B, which is the first arm 34C. The first through hole 34h of the first arm 34C has a counterbore (recess) 34Cc formed on the outside in the width direction C, which has a larger outer diameter than the rest of the first through hole 34h. The counterbore 34Cc is formed by press working as well as additional processing performed before and after press working. The pin 36 is fixed to the counterbore 34Cc by crimping.

[0118] 300 Endoscopic treatment system 200 Endoscope 100, 100B Endoscopic treatment instrument (treatment instrument) 110 Treatment section (end effector) 120 Bracket assembly 1 Sheath 11 Coil sheath 12 Covering tube 2 Transmission member 21 Wire 22 Pipe 23 Inner tube 3, 3B Support member 31, 31B Bracket 32, 32B Support body (base end) 33, 33B Arm 34, 34A, 34B, 34C First arm 34b Inclined section 34c, 34Bc, 34Cc Counterbore (recess) 34e Outer surface 34h First through hole 34i Inner surface 34n Notch 34s Bottom surface 35, 35B Second arm 35b Inclined section 35e Outer surface 35h Second through hole 35i Inner surface 36, 36A, 36B, 36C, 36D, 36E Pin (shaft, rotating shaft, rotating shaft member) 36a First end 36b Second end 36d, 36Ed Main cylindrical part 36Dd Main rectangular prism part 36f, 36Cf, 36Ef Flare part 36g Relief groove 36k Relief groove 37 Link mechanism 37b First link 37c Second link 38 Sheath connector 39 Connector 4 Forceps (jaws) 4P Pair of plates (pair of pieces) 41 First forceps piece 41c First cup 41e First edge 41h Through hole 41p First plate (left plate, left piece) 41t First serrated part 42 Second forceps piece 42c Second cup 42e Second edge 42h Through hole 42p 1. Second plate (right plate, right piece) 42t Second sawtooth section 5. Operating section (handle, handle assembly) 6. Handle body 60, 60A First handle body 60r Resin component 61. Second handle body 62. Thumb ring 64. Connector support section 65. Through hole 66, 66A. Plug socket 66s, 66As. Slit 67. Support section 69. Coil sheath support section 7. Electrical connector (connecting component, plug) 70. Upper end 71. Connecting section 72. Insertion passage 74. Powered plug 74s. Slit 75. Reduced diameter section 8. Slider

Claims

1. A bracket assembly for a medical device, comprising: a bracket having a base end and a plurality of arms extending from the base end; a shaft extending between the plurality of arms; and a pair of pieces supported on the shaft between the plurality of arms, wherein the plurality of arms are fixed to the shaft in a state in which they are elastically deformed toward the pair of pieces.

2. The bracket assembly for a medical device according to claim 1, wherein the shaft has a first end and a second end, the first end penetrates a first arm among the plurality of arms, and the end of the first end is provided with a flared portion that locks onto the first arm.

3. The tip of the first arm has a recess, the thickness of the flared portion is less than the depth of the recess, and the flared portion is locked to the bottom surface of the recess, the bracket assembly for a medical device according to claim 2.

4. The bracket assembly for a medical device according to claim 2, wherein the tip of the first arm has a recess, and the flared portion is locked to the bottom surface of the recess when the plurality of arms are elastically deformed in a direction toward the pair of pieces.

5. The bracket assembly for a medical device according to claim 3 or 4, wherein the second end is fixed to the second arm of the plurality of arms, and when the plurality of arms and the pair of pieces are brought into contact, a gap is created between the bottom surface of the recess and the flared portion.

6. The bracket assembly for a medical device according to claim 5, wherein the plurality of arms are elastically deformed in a direction toward the pair of pieces, and the second end is fixed to the second arm by welding.

7. The bracket assembly for a medical device according to claim 1, wherein the outer surface of the bracket is inclined from the base end of the bracket toward the tips of the plurality of arms.

8. The bracket assembly for a medical device according to claim 1, wherein the inner surface of the bracket is inclined from the base end of the bracket toward the tips of the plurality of arms.

9. The bracket assembly for a medical device according to claim 1, wherein the width of the pair of pieces in the longitudinal axis direction of the shaft is smaller than the distance between the base ends of the plurality of arms.

10. The bracket assembly for a medical device according to claim 1, wherein the base end of the bracket has a cylindrical portion, and a connector connected to the pair of pieces is inserted through the inside of the cylindrical portion.

11. The bracket assembly for a medical device according to claim 10, wherein the length of the arm in the longitudinal axis direction of the connector is longer than the length of the cylindrical portion.

12. The bracket assembly for a medical device according to claim 1, wherein the bracket is formed by machining.

13. The bracket assembly for a medical device according to claim 1, wherein the bracket is formed by press working.

14. The flared portion is a flange, as described in claim 2, for a medical device bracket assembly.

15. An endoscopic treatment instrument comprising: a sheath; a bracket having a base end that abuts the sheath and a plurality of arms extending from the base end; a shaft extending between the plurality of arms; and a pair of pieces supported on the shaft between the plurality of arms, wherein the plurality of arms are fixed to the shaft in a state in which they are elastically deformed in a direction toward the pair of pieces.

16. The endoscopic treatment instrument according to claim 15, wherein the sheath comprises a coil sheath and a sheath connector connected to the tip of the coil sheath, and the bracket is rotatably connected to the sheath connector on the outside of the sheath connector.

17. A method for assembling a bracket assembly comprising a bracket having a plurality of arms, a shaft extending between the plurality of arms, and a pair of pieces supported by the shaft between the plurality of arms, wherein the plurality of arms are elastically deformed in a direction toward the pair of pieces, with a flared portion provided at the end of the shaft aligned with the outer surface of the first arm among the plurality of arms, and the end of the shaft opposite to the flared portion is fixed to the second arm among the plurality of arms.

18. A method for assembling a bracket assembly for a medical device according to claim 17, wherein a jig is used to align the flared portion of the shaft with the outer surface of the first arm.

19. A method for assembling a bracket assembly for a medical device according to claim 17, wherein the outer surface of the bracket is pressed against it with a jig to cause elastic deformation.

20. The method for assembling a bracket assembly for a medical device according to claim 17, wherein the flared portion is locked to the bottom surface of the recess by releasing the jig from the bracket.

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