JP2009125414A - Biopsy forceps for endoscope - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide biopsy forceps for an endoscope, capable of surely and smoothly cutting biopsy tissue by a pair of forceps cups and preventing the biopsy tissue from being torn and damaged more than needed when sampling the biopsy tissue. <P>SOLUTION: In the biopsy forceps for the endoscope, the inner peripheral dimension of the opening end of a first forceps cup is smaller than the outer peripheral dimension of the opening end of a second forceps cup, at least one of the first forceps cup and the second forceps cup is provided with a slit formed at the opening end, and when the pair of forceps cups are closed centering on a support shaft by an opening/closing means, the inner edge of the opening end of the first forceps cup and the outer edge of the opening end of the second forceps cup are closed while being in slidable contact in the order from the proximal end side to the distal end. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an endoscopic biopsy forceps that is used by being inserted into a forceps channel of an endoscope.

  The endoscopic biopsy forceps are inserted into a forceps channel (forceps conduit) of an endoscope to collect a biopsy tissue specimen from the body cavity. Conventionally, as a biopsy forceps for an endoscope, an operation wire having a pair of forceps cups connected to the distal end is inserted and disposed in the sheath, and the operation wire is advanced and retracted in the extending direction thereof. A device that opens and closes a forceps cup in a bowl shape is known. The biopsy forceps for endoscope collects a biopsy tissue in each closed forceps cup by closing a pair of forceps cups.

  As such an endoscopic biopsy forceps, for example, Patent Document 1 discloses an endoscope for which an edge portion of at least one forceps cup is formed in a sawtooth shape among a pair of forceps cups that open and close like a bowl. It is described that, in the mouth-opening biopsy forceps, when the pair of forceps cups are closed, the two edge portions pass each other before closing.

  Further, in Patent Document 2, the size of the opening ends facing each other between the pair of forceps cups is made different, and the tissue cutting edge of the smaller forceps cup is placed in the tissue cutting edge of the larger forceps cup. An endoscopic biopsy forceps is described which is engaged in a guided state and sandwiches and cuts a biopsy tissue.

JP 2002-191606 A JP 2000-210294 A

  In conventional endoscopic biopsy forceps, when a pair of forceps cups of a biopsy forceps is closed, an irregular force is applied to the forceps cup when the biopsy tissue is collected in each closed forceps cup. A lateral shift or tilt may occur between the forceps cups. If a lateral displacement or inclination occurs between the forceps cups, the engagement of the blade-like edges of the forceps cups may be displaced, and the biopsy tissue may not be cut properly. If the biopsy tissue sandwiched between the pair of forceps cups cannot be cut reliably, the biopsy tissue sandwiched between the biopsy forceps will be torn off, and the tissue may be damaged more than necessary. .

  With respect to this problem, in Patent Document 1, the edge portion of the forceps cup is formed in a sawtooth shape, and when the pair of forceps cups are fully closed, the edges of both blades are closed and then closed. The biopsy tissue is cut smoothly. However, the biopsy forceps described in Patent Document 1 has a structure in which a serrated edge bites into a biopsy tissue at a plurality of points at the same time, and is not necessarily a mechanism that can cut smoothly. Also, the force required to cut the sandwiched biopsy tissue is relatively large.

  Furthermore, the biopsy forceps of Patent Document 1 have a difference in the size of the forceps cup so that the edge of the other forceps cup slides into the inside of the edge of one forceps cup. If the dimensions of the parts vary, it may be impossible to close the pair of forceps cups. Therefore, advanced dimensional management is necessary in the manufacturing process, and costs are increased. Even when manufactured with high precision, when the forceps cup is closed while the biopsy tissue is sandwiched between the forceps cups, if the forceps cup is subjected to an irregular force and lateral displacement or tilt occurs, the edges of both forceps cups May slip and become unengaged.

  In Patent Document 2, the tissue cutting edge of the smaller forceps cup is engaged with the tissue cutting edge of the larger forceps cup so that the biopsy tissue is reliably cut to the end. It is also described that the outer peripheral portion of the open end of the smaller forceps cup may be in sliding contact with the inner peripheral surface of the larger forceps cup. However, because the small forceps cup is guided inside the large forceps cup, the biopsy tissue sandwiched between the open end of the small forceps cup and the inner peripheral surface of the large forceps cup The shearing force does not act, and the structure is such that the tissue is pushed between the edges of the pair of forceps cups.

  Therefore, the biopsy forceps of Patent Document 2 cannot cut tissue unless the outer peripheral portion of the opening end of the smaller forceps cup is very sharp. In addition, if there are variations in the dimensions of the parts, there may be a gap between the forceps cups, which may make it impossible to close them completely. Therefore, advanced dimensional management is required in the manufacturing process, which increases costs. .

An object of the present invention is to solve the problems of the prior art described above, and when collecting a biopsy tissue, the biopsy tissue can be reliably and smoothly cut with a pair of forceps cups. It is an object of the present invention to provide an endoscopic biopsy forceps capable of preventing a tissue from being torn off and damaging the tissue more than necessary.
Furthermore, an object of the present invention is to provide such an endoscopic biopsy forceps that can be manufactured at low cost.

  In order to achieve the above object, the present invention comprises a first forceps cup and a second forceps cup, and when closed, the second forceps cup is placed inside the open end of the first forceps cup. A pair of forceps cups having overlapping opening ends, a support shaft for pivotally connecting a base end portion of the first forceps cup and a base end portion of the second forceps cup, and the first forceps An endoscopic biopsy forceps having a cup and an opening / closing means for opening and closing the second forceps cup in a hook shape around the support shaft, and an inner peripheral dimension of an opening end portion of the first forceps cup Is smaller than the outer peripheral dimension of the opening end portion of the second forceps cup, and at least one of the first forceps cup and the second forceps cup has a slit at the opening end portion, The forceps cup is centered on the support shaft by the opening / closing means. The inner edge of the opening end portion of the first forceps cup and the outer edge of the opening end portion of the second forceps cup are closed while sliding in order from the base end side toward the tip end. An endoscopic biopsy forceps is provided.

In such an endoscopic biopsy forceps of the present invention, it is preferable that the slit is formed at the tip of the opening end.
Furthermore, it is preferable that at least one of the first forceps cup and the second forceps cup has slits on both sides of the base end portion.
In addition, it is preferable that the first forceps cup and the second forceps cup have different rigidity at least at the opening end.
Further, when at least one of the first forceps cup and the second forceps cup closes the pair of forceps cups, the first forceps cup and the second forceps cup first come into contact with each other. And a pair of forceps cups for guiding the open end of the second forceps cup to the inside of the open end of the first forceps cup, wherein the pair of forceps cups are open ends of the first forceps cup When the opening / closing means is closed around the support shaft from a position where the opening portion of the second forceps cup is separated from the opening end portion of the second forceps cup, the opening end portion of the second forceps cup is It is preferable that the first forceps cup is guided inside the opening end.

  According to the endoscopic biopsy forceps of the present invention having the above-described configuration, the pair of forceps cups includes an inner peripheral surface of the opening end portion of the first forceps cup and an outer peripheral surface of the opening end portion of the second forceps cup. Are the press-fitting dimensions, and a slit was formed when the opening end of the second forceps cup was press-fitted into the inner peripheral surface of the opening end of the first forceps cup and closed around the support shaft. When the forceps cup is elastically deformed, the first forceps cup and the second forceps cup can be easily fitted. As described above, after the first forceps cup and the second forceps cup are fitted, the inner peripheral surface of the edge portion of the first forceps cup and the outer peripheral surface of the edge portion of the second forceps cup are in sliding contact. However, it is closed from the proximal end side toward the distal end side. As a result, the shearing action of scissors by point contact can be realized between the inner edge of the edge of the first forceps cup and the outer edge of the edge of the second forceps cup, and the biopsy tissue is cut reliably. can do.

  Hereinafter, the biopsy forceps for endoscope of the present invention will be described in detail based on preferred embodiments shown in the accompanying drawings.

FIG. 1 is a front view showing a schematic configuration of a biopsy forceps 10 which is an embodiment of an endoscopic biopsy forceps (hereinafter referred to as biopsy forceps) according to the present invention.
The biopsy forceps 10 is attached to a forceps portion 12 for collecting a biopsy tissue, an insertion portion 14 to which a forceps portion 12 is attached at a distal end thereof, inserted into a forceps channel of an endoscope, and a proximal end of the insertion portion 14. And an operation unit 16 for operating the forceps unit 12. The biopsy forceps 10 inserts the insertion portion 14 into the forceps channel of the endoscope, and operates the forceps portion 12 protruding from the distal end portion of the endoscope by the operation portion 16 on the operation portion side of the endoscope. The biopsy tissue is collected.

FIG. 2 is a perspective view schematically showing the forceps portion 12 shown in FIG.
As shown in FIG. 2, the forceps unit 12 includes a pair of forceps cups 28 including a first forceps cup 30 and a second forceps cup 40, a support shaft 50 that supports the pair of forceps cups 28, and a support shaft. An opening / closing means 20 that opens and closes a pair of forceps cups around 50 and a support member 22 that is disposed at the distal end of the insertion portion 14 (the distal end of the sheath) and supports the support shaft 50 of the forceps portion 12.

  FIG. 3 is a partial cross-sectional view schematically showing the configuration of the distal end portions of the forceps portion 12 and the insertion portion 14. FIG. 3 shows the entire opening / closing means 20 disposed inside the support member 22 except for the front half of the support member 22, and the inside of the support member 22 except for the front half of the sheath 60 of the insertion portion 14 described later. The configuration is shown.

  The first forceps cup 30 includes a cup body 32 having a substantially hemispherical recess, an edge (opening end) 34 erected along the opening end of the recess of the cup body 32, and the cup body 32. And a connecting portion 36 that extends to the base end portion on the base end side and is connected to a link 52 of the opening / closing means 20 described later. In addition, the shape of the recessed part of the cup main body 32 is not limited to a substantially hemispherical shape, and may be various shapes such as a tapered shape, an elliptical spherical shape, and a rectangular parallelepiped shape.

  Further, the edge portion 34 of the first forceps cup 30 has a chamfered portion 38 at an inner corner portion on the proximal end side. The edge portion 34 of the first forceps cup 30 is inclined from the outside to the inside from the proximal end side toward the distal end side at the inner corner portion on the proximal end side. In other words, the edge portion 34 is configured by the chamfered portion 38 so that the opening width of the cup becomes wider toward the base end side.

  The second forceps cup 40 includes a cup body 42 having a substantially hemispherical concave portion, an edge portion (opening end portion) 44 that is an open end of the concave portion of the cup main body 42, and a proximal end on the proximal end side of the cup main body 42. And a connection portion 46 that extends to the base end portion 45 and is connected to a link 54 of the opening / closing means 20 described later. In addition, the shape of the recessed part of the cup main body 42 is not limited to a substantially hemispherical shape, and may be various shapes such as a tapered shape, an elliptical spherical shape, and a rectangular parallelepiped shape. Note that the edge portion 44 of the second forceps cup 40 may be erected along the open end of the concave portion of the cup main body 42 in the same manner as the edge portion 34 of the first forceps cup.

  The second forceps cup 40 has a slit 47 formed at a distal end portion of the edge portion 44 with a substantially constant width in a direction perpendicular to the end surface of the edge portion 44. In the illustrated example, the depth of the slit 47 is equal to or deeper than the length of the portion overlapping the edge portion 34 of the first forceps cup 30, but is not limited to this in the present invention. It may be shallower or deeper. In the illustrated example, the slit 47 has a substantially constant width in the depth direction. However, in the present invention, the slit 47 is not limited to the above-described shape. For example, the slit 47 gradually decreases in the depth direction. It may be in the shape of an inverted V-shape that gradually increases in width in the depth direction.

  In the present embodiment, the cup body 42 of the second forceps cup 40 is formed with a single slit 47 at the center of the tip of the edge 44, and passes through the center of the cup body 42 to open and close the shaft. It becomes symmetrical with respect to the line orthogonal to the support shaft 50. In this configuration, when the pair of forceps cups 28 is closed, the cup body 42 can be similarly deformed at both side portions when the cup body 42 receives an inward force from both sides thereof. On both sides thereof, the sliding contact state with the edge 34 of the first forceps cup 30 can be made similar, and the shape of the cup body 42 is simple, which is preferable. However, in the present invention, the formation position and number of slits are not limited to the above form, and a plurality of slits may be formed in the edge portion 44 at appropriate intervals. For example, two slits may be formed at a position shifted from the center of the tip of the edge 44 so as to sandwich the center of the tip. However, the slit is preferably arranged at a position where both sides are symmetrical with respect to the center of the tip of the edge portion 44.

The second forceps cup 40 has slits 48 and 49 at both end portions of the base end portion 45 of the cup body 42. The slits 48 and 49 separate the edge portion 44 and the base end portion 45.
In the present embodiment, the slits 48 and 49 are provided on both sides of the base end portion 45 of the cup body 42, so that when the cup body 42 receives a force inward from the both sides, It is preferable in that it can be similarly deformed at both side portions. However, the present invention is not limited to this, and a slit may be formed on either one of both sides of the base end, that is, only one of the slits 48 and 49 is formed. Also good.

  The edge 44 of the second forceps cup 40 is separated into two parts, an edge piece 44a and an edge piece 44b, by slits 47, 48 and 49. With this configuration, the second forceps cup 40 can be deformed so that the two edge pieces 44a and 44b approach each other when the edge 44 receives a force directed toward the inside of the cup.

  The first forceps cup 30 and the second forceps cup 40 are rotatable about a support shaft 50 fixed to the support member 22 at connection portions 36 and 46 extending to the base end sides of the cup bodies 32 and 42. It is connected. The first forceps cup 30 and the second forceps cup 40 are configured such that when the cup main bodies 32 and 42 are connected to the support shaft 50 and the cup main bodies 32 and 42 are closed, the openings of the cup main bodies 32 and 42 are combined. . In other words, the pair of forceps cups 28 including the first forceps cup 30 and the second forceps cup 40 is configured to be openable and closable in a hook shape around the support shaft 50 fixed to the support member 22.

  The pair of forceps cups 28 is opened until the cup body 32 of the first forceps cup 30 and the cup body 42 of the second forceps cup 40 are completely separated at the time of opening, that is, in the preparation stage for collecting the biopsy tissue. Can do. Thus, by increasing the opening angle between the first forceps cup 30 and the second forceps cup 40, it is possible to sufficiently collect biopsy tissue.

  In addition, when the pair of forceps cups 28 is closed, that is, when a biopsy tissue is collected, an edge portion 34 erected from the end surface of the concave portion of the cup body 32 of the first forceps cup 30 has a second forceps cup 40. Close until it overlaps the edge 44 of

  Here, in the biopsy forceps 10, the inner peripheral surface of the edge portion 34 of the first forceps cup 30 and the outer peripheral surface of the edge portion 44 of the second forceps cup 40 have substantially the same shape. In addition, the dimension of the inner periphery of the edge 34 of the first forceps cup 30 is smaller than the dimension of the outer periphery of the edge 44 of the second forceps cup 40. That is, the inner peripheral surface of the edge portion 34 of the first forceps cup 30 and the outer peripheral surface of the edge portion 44 of the second forceps cup 40 that is inserted inside the first forceps cup 30 have a press-fit dimension relationship. ing.

Next, the operation of the pair of forceps cups 28 will be described.
In the biopsy forceps 10, as shown in FIG. 2, the pair of forceps cups 28 includes an edge portion 34 of the cup body 32 of the first forceps cup 30 and an edge portion 44 of the cup body 42 of the second forceps cup 40. From the position where the first forceps cup 30 and the second forceps cup 40 are centered on the support shaft 50, the opening and closing means 20 described below closes the first forceps cup 30 and the second forceps cup 40 from the proximal end side toward the distal end side.

  When the pair of forceps cups 28 starts to close, the first forceps cup 30 and the second forceps cup 40 first come into contact with each other at the corners on the base end side. At this time, the edge portion 44 of the second forceps cup 40 having a size larger than the inner circumference of the edge portion 34 of the first forceps cup 30 is a chamfered portion formed on the edge portion 34 of the first forceps cup 30. The (lead-in part) 38 is guided to the inner peripheral surface side of the edge part 34 of the first forceps cup 30 and press-fitted.

  When the edge portion 44 of the second forceps cup 40 is press-fitted into the edge portion 34 of the first forceps cup 30, the second forceps cup 40 exerts a force toward the inside of the cup body 42 on the base end side. Receive from the first forceps cup 30. At this time, since the slits 48 and 49 are formed in the second forceps cup 40, in other words, the edge pieces 44 a and 44 b receive the force from the first forceps cup 30 and approach each other. Then, the edge pieces 44 a and 44 b are deformed toward the inside of the cup body 40 in a direction approaching the base end portion 45. Thereby, the pair of forceps cups 28 can press the edge 44 into the edge 34 without difficulty, and can easily fit the edge 34 and the edge 44 together.

  After the edge portion 44 of the second forceps cup 40 is press-fitted into the inner peripheral surface side of the edge portion 34 of the first forceps cup 30 and the edge portion 34 and the edge portion 44 are fitted together, the pair of forceps cups 28 is When further closed, the inner peripheral surface of the edge portion 34 of the first forceps cup 30 and the outer peripheral surface of the edge portion 44 of the second forceps cup 40 are closed toward the front end side while sliding. As described above, since the inner peripheral surface of the edge portion 34 of the first forceps cup 30 and the outer peripheral surface of the edge portion 44 of the second forceps cup 40 are in a press-fitting dimension, the first forceps cup 30. The inner peripheral surface of the edge portion 34 and the outer peripheral surface of the edge portion 44 of the second forceps cup 40 are gradually slidably closed while being pressed from the proximal end side toward the distal end side. Finally, as shown in FIG. 3, the pair of forceps cups 28 is press-fitted inside the edge 34 of the first forceps cup 30 until the edge 44 of the second forceps cup 40 reaches its tip. It will be in a closed state.

  When the pair of forceps cups 28 is further closed from the proximal end side toward the distal end side, the second forceps cup 40 receives a force from the first forceps cup 30 toward the inside of the cup body 42. At this time, since the slits 47 are formed in the second forceps cup 40, the edge pieces 44a and 44b are close to each other at the distal end thereof upon receiving the force from the first forceps cup 30. Then, it is deformed toward the inside of the cup body 40. Thereby, the pair of forceps cups 28 can fit the edge portion 34 and the edge portion 44 without difficulty.

  When the pair of forceps cups 28 is closed as described above, the biopsy forceps 10 of the present invention is between the edge portion 34 of the first forceps cup 30 and the edge portion 44 of the second forceps cup 40. The biopsy tissue collected by the pair of forceps cups 28 is cut by the shearing action of scissors by point contact at one point on each side.

  In the present embodiment, the closed state of the pair of forceps cups 28 means that the opening end of the cup body 32 of the first forceps cup 30 and the opening end (edge portion) of the cup body 42 of the second forceps cup 40. 44) refers to a state in which contact is substantially made from the base end side to the tip end side, preferably a complete contact state. Thus, when the pair of forceps cups 28 is closed, the edge 44 of the second forceps cup 40 enters inside the edge 34 of the first forceps cup 30, and the inner peripheral surface of the edge 34. And the outer peripheral surface of the edge part 44 is in the state which contacted.

  Thus, when the edge portion 44 of the second forceps cup 40 is press-fitted into the edge portion 34 of the first forceps cup 30, the second forceps cup 40 in which the slits 47, 48, and 49 are formed is In response to the force from the first forceps cup 30, the edge pieces 44 a and 44 b are deformed toward the inside of the cup body 40 in a direction in which they approach each other. That is, by forming slits 47, 48, and 49 in the second forceps cup 40, the rigidity of the second forceps cup 40 with the slits is made smaller than that of the first forceps cup 30 and elastically deformed. It can be made easier. Thereby, the edge part 34 and the edge part 44 can be made to fit reasonably.

  Further, by providing slits 47, 48, and 49 in the second forceps cup 40, the second forceps against the force in the meshing direction toward the inside of the cup body 42, which is the force in the direction of narrowing the slit width. The cup 40 can be easily elastically deformed, and the second forceps cup 40 as a whole can ensure rigidity and strength necessary for a forceps cup of a biopsy forceps. Thereby, the operating force for engaging the pair of forceps cups 28, that is, the operating force required for press-fitting and sliding contact, can be reduced, and the rigidity and strength of the second forceps cup 40 can be ensured.

  Further, when the pair of forceps cups 28 is closed, the inner peripheral surface of the edge portion 34 of the first forceps cup 30 and the outer peripheral surface of the edge portion 44 of the second forceps cup 40 are in sliding contact with each other from the proximal end side. It is closed toward the distal end side, so that a shearing action of scissors by point contact can be realized between the edge 34 of the first forceps cup 30 and the edge 44 of the second forceps cup 40. The biopsy tissue can be cut reliably. Thus, unnecessary bleeding can be prevented without damaging the tissue more than necessary by tearing the biopsy tissue.

The first forceps cup 30 or the second forceps cup 40 of the pair of forceps cups 28 may be provided in the pair of forceps cups 28, but the second forceps cup 40 that enters inside in the closed state as in the present embodiment is provided. It is preferable to provide it because a high pressure contact state can be obtained and the action of scissors can be obtained effectively.
Furthermore, when closing the pair of forceps cups 28 by providing a slit 47 at the distal end portion of the second forceps cup 40 that enters inside in the closed state of the pair of forceps cups 28 as in this embodiment, The slit 47 can be deformed in the direction of narrowing the width. Thereby, in a state where the pair of forceps cups 28 is closed, the cut by the slit 47 at the distal end portion of the second forceps cup 40 can be eliminated or the cut can be narrowed, that is, the sliding between the pair of forceps cups 28 can be achieved. It is possible to prevent or minimize the area that does not contact, and it is possible to suitably obtain the shearing action of scissors by sliding contact.

  Here, the width of the slit 47 takes into account the amount of deformation of the second forceps cup 40 when the pair of forceps cups 28 is changed from the opened state to the closed state, and the second forceps cup 40 is closed. In this state, it is preferable to determine that the edge pieces 44a and 44b are in contact with each other at the tip portion. Thereby, when the pair of forceps cups 28 is closed, the shearing action of scissors due to the sliding contact can be suitably obtained even at the distal end portion, and the biopsy tissue can be cut reliably.

  Further, in the present embodiment, a slit 47 at the distal end and slits 48 and 49 on both sides of the proximal end 45 are provided, and among these slits, the second forceps cup 40 in particular due to the contribution of the slits 48 and 49 is provided. Due to the elastic deformation, the second forceps cup 40 can be pressed into the first forceps cup 30 without difficulty, and among these slits, the elastic deformation of the second forceps cup 40 due to the contribution of the slit 47 in particular. Thus, the pair of forceps cups 28 is most preferable in that the fitting between the pair of forceps cups 28 can be performed without difficulty from the proximal end to the distal end. However, the present invention is not limited to the above embodiment, and the effect of elastic deformation of the second forceps cup 40 can be obtained even when only the slit 47 or only the slits 48 and 49 are used.

  For example, even in the case of only the slit 47, the second forceps cup 40 contributes to the elastic deformation of the second forceps cup 40 by the slit 47 when the second forceps cup 40 is pressed into the first forceps cup 30. The forceps cup 40 can be preferentially deformed and can be press-fitted without difficulty. Further, for example, even when only the slits 48 and 49 are provided, the second forceps cup 40 can be easily elastically deformed in the meshing direction by the slits 48 and 49 when the pair of forceps cups 28 is in sliding contact. The pair of forceps cups 28 can be easily fitted from the proximal end to the distal end.

  Note that the first forceps cup 30 (cup body 32) and the second forceps cup 40 (cup body 42) have at least the edge 34 and the edge 44 due to differences in material and thickness in addition to the formation of slits. The whole may have relatively different rigidity.

  By providing the rigidity difference in this way, the second forceps cup 40 is press-fitted into the first forceps cup 30, and the edge portion 34 of the first forceps cup 30 and the edge portion 44 of the second forceps cup 40 are When the cup is in sliding contact, the cup body having the smaller rigidity is elastically deformed, so that it can be fitted without difficulty while maintaining the press contact state between the edge 34 and the edge 44, and the scissors caused by the sliding contact A shearing action can be suitably obtained.

  In particular, when a slit is provided in the second forceps cup 40 that enters inside in the closed state as in the present embodiment, the material of the second forceps cup 40 is less rigid than the first forceps cup 30. The thickness of the second forceps cup 40 can be preferentially deformed with respect to the first forceps cup 30, and the shearing action of the scissors by sliding contact is suitably obtained. be able to.

  In the biopsy forceps 10 having the above-described configuration, the gap between the edge portion 34 of the first forceps cup 30 and the edge portion 44 of the second forceps cup 40 (the inner edge of the edge portion 34 of the first forceps cup 30 and the second edge of the second forceps cup 30). Since the shearing action of the scissors by the point contact can be realized between the edge of the forceps cup 40 and the outer edge of the forceps cup 40, it is not necessary to sharpen the end faces of the edge 34 and the edge 44 sharply. That is, in the case of cutting by pressing a blade-like edge portion, the edge surface of the edge portion needs to be as sharp as possible. In the present invention, the edge portion where the edge portion 34 and the edge portion 44 are in sliding contact with each other is its ridgeline. It is sufficient that the pin angle is a substantially right angle with no R attached thereto, and it is not necessary to sharply finish, whereby the durability of the edge 34 and the edge 44 can be improved, and the processing cost is reduced. be able to. The edge 34 and the edge 44 preferably have an ideal pin angle of R = 0. However, if the edge 34 and the edge 44 have sufficient durability as the edge of a biopsy forceps cup, It is good also considering the part 34 and the edge part 44 as a sharp blade shape.

  Further, since the shearing action of scissors by point contact can be realized between the edge portion 34 of the first forceps cup 30 and the edge portion 44 of the second forceps cup 40, and the cutting force is good, the cutting force is small. Can cut tissue. Accordingly, the first forceps cup 30 and the second forceps cup 40 and each member constituting the forceps portion 12 can be made of a material having relatively low rigidity such as resin and sheet metal, and the production cost can be reduced. it can.

Further, when the chamfered portion 38 is provided on the edge 34 of the first forceps cup 30, the first forceps cup 30 and the second forceps cup 40 are closed from the separated state around the support shaft 50. In addition, the edge 44 of the second forceps cup 40, which has a press-fitting dimension relationship with the edge 34 of the first forceps cup 30, is reliably guided to the inside of the edge 34 of the first forceps cup 30. Therefore, even if the first forceps cup 30 and the second forceps cup 40 are slightly laterally shifted or tilted, the first forceps cup 30 and the second forceps cup 40 can be prevented from affecting the cutting of the biopsy tissue, and the edge 44 of the second forceps cup 40 is surely press-fitted to the inner peripheral surface side of the edge 34 of the first forceps cup 30 and cut. be able to.
In particular, even if the edge 34 and the edge 44 are closed from the separated state as in the biopsy forceps 10 of the present embodiment, the second forceps cup 40 is not affected by the lateral displacement. The first forceps cup 30 can be reliably press-fitted.

  In addition, since the chamfered portion 38 can surely guide (lead) the inside of the edge portion 34 of the first forceps cup 30, each member such as the first forceps cup 30 and the second forceps cup 40 is slightly attached. Even when there is a dimensional error, the first forceps cup 30 and the second forceps cup 40 can be properly engaged, and the dimensional error of each member can be allowed. Therefore, it is not necessary to manufacture each member with high dimensional accuracy, and manufacturing cost can be suppressed.

  In the present embodiment, the edge portion 34 of the first forceps cup 30 and the edge portion 44 of the second forceps cup 40 may be curved along the curvature of the cup, but are flat at the tip portion thereof. It is preferable to have a surface. In addition, the overlapping amount of the edge portion 34 of the first forceps cup 30 and the edge portion 44 of the second forceps cup 40 is such that the edge portion 34 and the edge portion 44 can reliably overlap each other in the closed state. For example, 0.01 mm or more is preferable. With these configurations, the action of the scissors can be effectively exhibited.

  In the present embodiment, the edge 34 of the first forceps cup 30 that is outside when the pair of forceps cups 28 is closed is provided so as to extend from the open end of the cup body 32. The edge 34 and the edge 44 may be overlapped by extending the edge 44 of the second forceps cup 40 that is inside from the opening end of the cup body 42, or the edge 34 and the edge The edge portion 34 and the edge portion 44 may overlap each other by providing the portion 44 so as to extend from the opening end of each cup body.

  In the present embodiment, a chamfered portion 38 is provided on the edge portion 34 of the first forceps cup 30. The chamfered portion 38 is preferable in that it is not necessary to provide other members and is easy to form. However, the present invention is not limited to this, and when the pair of forceps cups 28 is closed from the proximal end side, the edge portion 34 of the first forceps cup 30 and the edge portion 44 of the second forceps cup 40 are connected. What is necessary is just to form the shape which can guide | invade the edge part 44 to the inner peripheral surface side of the edge part 34 as a guide part in the base end side which contacts first.

  For example, a chamfered portion that is inclined from the inside toward the outside from the proximal end side toward the distal end side may be provided at the corner portion of the outer edge on the proximal end side of the edge portion 44 of the second forceps cup 40 as the guiding portion. Even in this case, the edge portion 44 of the second forceps cup 40 and the edge portion 34 of the first forceps cup 30 are not affected by the lateral displacement or deformation of the first forceps cup 30 and the second forceps cup 40. Can be reliably press-fitted into the inner peripheral surface side, and the same effect as in the present embodiment can be obtained. In addition, a guiding portion may be formed on both the first forceps cup 30 and the second forceps cup 40.

Next, the opening / closing means 20 will be described with reference to FIGS.
The opening / closing means 20 includes a link 52 coupled to the connection portion 36 of the first forceps cup 30, a link 54 coupled to the connection portion 46 of the second forceps cup 40, and the link 52 and the link 54 coupled. The connecting rod 36 of the first forceps cup 30 and the connecting portion 46 of the second forceps cup 40 are formed to form a pantograph-like link mechanism.

The connection portion 36 of the first forceps cup 30 is rotatably connected to one end of the link 52 by a pin 53, and the connection portion 46 of the second forceps cup 40 is rotated to one end of the link 54 by a pin 55. It is connected freely.
The other ends of the links 52, 54, that is, the end opposite to the side connected to the connecting portions 36, 46 are rotatably connected to the tip of the operation rod 56 by a pin 58. The proximal end side of the operation rod 56 is fixed to the distal end of the operation wire 18.

  In the opening / closing means 20 having the above-described configuration, when the operation wire 18 advances and retreats in the axial direction by an operation from the operation unit 16, the operation rod 56 fixed to the operation wire 18 advances and retreats in the same direction, and the movement is linked to the links 52 and 54. The pair of forceps cups 28 is opened and closed around the support shaft 50 by transmitting to the first forceps cup 30 and the second forceps cup 40 via.

  The opening / closing means 20 has links 52 and 54 and forms a pantograph-like link mechanism. However, in the present invention, the opening / closing means is not limited to the above-described configuration, and the links 52 and 54 are provided. The pair of forceps cups 28 may be opened and closed around the support shaft 50 by directly connecting the operation wires to the connection portions 36 and 46 and moving the operation wires forward and backward.

  Next, as shown in FIGS. 1 and 3, the insertion portion 14 includes a flexible sheath 60 that is inserted into the forceps channel of the endoscope, and an operation wire 18 that is inserted into the sheath 60. For example, as shown in FIGS. 1 and 3, the sheath 60 is made of a metal wound coil pipe. However, the present invention is not limited to this, and has flexibility, and has the operation wire 18 inside. A cylindrical shape having a space to be inserted may be used. The operation wire 18 has a distal end connected to the operation rod 56 of the forceps portion 12 and a proximal end connected to the operation portion 16.

The operation unit 16 is attached to the proximal end of the insertion unit 14 and is used to operate the forceps unit 12. As shown in FIG. 1, the operation unit 16 includes a shaft-like body 62 and an operation element 66.
The distal end portion of the shaft-like body 62 is fixed to the proximal end portion of the sheath 60 of the insertion portion 14. In addition, a ring-shaped finger hook portion 64 for inserting the operator's thumb at the time of operation is formed at the proximal end portion of the shaft-like body 62, that is, the end portion opposite to the distal end portion to which the operation wire 18 is fixed. Has been.

  The operation element 66 is a cylindrical member and is slidably fitted to the shaft-like portion of the shaft-like body 62. That is, the shaft-like body 62 is slidably inserted into the cylinder portion of the operation element 66. The operation element 66 includes a constricted portion 68 between the two disk-shaped flanges for hooking the index finger and middle finger of the operator during operation. The operation element 66 is connected to the operation wire 18 of the insertion portion 14. By sliding the operation element 66 so as to advance and retreat with respect to the shaft-like body 62, the operation wire 18 is advanced and retracted, and forceps at the distal end thereof. The opening / closing operation of the pair of forceps cups 28 of the unit 12 is operated.

  There is no particular limitation on the mechanism for advancing and retracting the operation wire 18 by sliding the operation element 66 with respect to the shaft-shaped body 62. For example, the axial direction of the shaft-shaped body 62 ( The slider is arranged so as to slide in the extending direction), and the screw provided on the inner surface of the operation element 66 is fixed to the slider, so that the operation element 66 and the slider are integrated with the shaft-like body 62. It can be configured to be movable in the axial direction. Then, by connecting the operation wire 18 to the slider and moving the operation element 66 in the axial direction relative to the shaft-like body 62, the operation wire 18 fixed to the slider can be advanced and retracted in the axial direction. .

  At the time of operation, the operator's thumb is put in the finger hook portion 64 of the shaft-like body 62, and the index finger and the middle finger are hooked on the constricted portion 68 of the operation element 66. In this state, the operation unit 16 is configured such that the operation element 66 is pushed and pulled in the axial direction with respect to the shaft-like body 62.

  The biopsy forceps 10 configured as described above moves the operation wire 18 forward and backward in the axial direction within the sheath 60 when the operator 66 pushes and pulls the operation element 66. As the operation wire 18 advances and retreats, the operation rod 56 fixed to the operation wire 18 advances and retreats, and the pair of forceps cups 28 connected to the operation rod 56 by the link mechanism opens and closes.

Next, another embodiment of a pair of forceps cups of a biopsy forceps will be described. FIG. 4 is a perspective view schematically showing a pair of forceps cups 70 according to another embodiment of the present invention.
In the pair of forceps cups 70 shown in FIG. 4, guide members 74 and 78 serving as meshing guide portions 80 are extended from the base end portions of the forceps cups 72 and 76. The pair of forceps cups 70 is different in that a pair of forceps cups 70 (see FIG. 2) in the above-described example is provided with an engagement guide portion 80 instead of the chamfered portion 38 (leading portion). Is the same.

That is, also in the pair of forceps cups 70 of the present embodiment, the edge 73 of the first forceps cup 72 and the edge 77 of the second forceps cup 76 are in a press-fitting dimension relationship, and the second forceps cup 70 The forceps cup 76 includes slits 47, 48, and 49. When the pair of forceps cups 70 is closed, the inner surface of the edge 73 of the first forceps cup 72 and the outer surface of the edge 77 of the second forceps cup 76 are provided. In the pressure contact state, point contact is made from the proximal end side toward the distal end side, and the biopsy tissue captured inside the cup is cut by the shearing action of scissors.
Further, the pair of forceps cups 70 are rotatably connected by a support shaft 82 indicated by a broken line in FIG. 4. Although not shown, the support shaft 82 is disposed inside the meshing guide portion 80. It is supported on the front end side.

  The first guide member 74 and the second guide member 78 include a first guide member 74 that extends from the first forceps cup 72 that is outside when the first guide member 74 is closed, and a second guide member 74 that is outside and inside. A second guide member 78 extending from the forceps cup 76 is disposed inside. There may be a gap between the inner surface of the first guide member 74 and the outer surface of the second guide member 78, but it is preferably always in contact with each other in order to guide them stably.

  The first guide member 74 and the second guide member 78 are configured to always maintain a meshed state regardless of whether the pair of forceps cups 70 is opened or closed and the degree of opening. Such a meshing guide portion 80 composed of the first guide member 74 and the second guide member 78 prevents the lateral displacement of the pair of forceps cups 70, and the second forceps cup has a second edge at the edge thereof. The edge of the forceps cup can be always press-fitted reliably.

  As mentioned above, although the biopsy forceps for endoscope of the present invention has been described in detail, the present invention is not limited to the above-described embodiments, and various improvements and modifications are made without departing from the gist of the present invention. Of course, you may.

It is a block diagram which shows typically one Embodiment of the biopsy forceps of this invention. It is a perspective view which shows typically the forceps part of the biopsy forceps shown in FIG. It is a fragmentary sectional view which shows typically the forceps part periphery of the biopsy forceps shown in FIG. It is a perspective view which shows typically other embodiment of a pair of forceps cup.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Biopsy forceps 12 Forceps part 14 Insertion part 16 Operation part 18 Operation wire 20 Opening / closing means 22 Support member 28, 70 A pair of forceps cups 30, 72 First forceps cup 32, 42 Cup main body 34, 44, 73, 77 Edge Portions 36, 46 Connecting portion 38 Chamfered portion 40, 76 Second forceps cup 44a, 44b Edge piece 45 Base end portion 47, 48, 49 Slit 50, 82 Support shaft 52, 54 Link 53, 55, 58 Pin 56 Operation Rod 60 Sheath 62 Shaft-shaped body 64 Finger-hanging part 66 Manipulator 68 Neck part 74 First guide member 78 Second guide member 80 Engagement guide part

Claims (5)

A pair of forceps cups, each comprising a first forceps cup and a second forceps cup, wherein the open end of the second forceps cup overlaps the open end of the first forceps cup when closed; A support shaft that rotatably connects a proximal end portion of the first forceps cup and a proximal end portion of the second forceps cup; and the support shaft that connects the first forceps cup and the second forceps cup to the support shaft. An endoscopic biopsy forceps having an opening and closing means for opening and closing in a bowl shape around
The inner peripheral dimension of the opening end of the first forceps cup is smaller than the outer peripheral dimension of the opening end of the second forceps cup, and
At least one of the first forceps cup and the second forceps cup has a slit at the opening end,
When the pair of forceps cups is closed around the support shaft by the opening / closing means, the inner edge of the opening end of the first forceps cup and the outer edge of the opening end of the second forceps cup are An endoscopic biopsy forceps which closes while sliding in order from the proximal end side toward the distal end.   The endoscopic biopsy forceps according to claim 1, wherein the slit is formed at a distal end portion of the opening end portion.   The endoscopic biopsy forceps according to claim 1 or 2, wherein at least one of the first forceps cup and the second forceps cup has slits on both sides of a base end portion thereof.   The biopsy forceps for endoscope according to any one of claims 1 to 3, wherein the first forceps cup and the second forceps cup have different rigidity at least at an opening end thereof. Furthermore, when at least one of the first forceps cup and the second forceps cup closes the pair of forceps cups, the first forceps cup and the second forceps cup first contact with each other. The second forceps cup has a lead-in portion that guides the open end of the second forceps cup into the open end of the first forceps cup;
When the pair of forceps cups is closed around the support shaft by the opening / closing means from a position where the opening end of the first forceps cup and the opening end of the second forceps cup are separated from each other, The endoscopic biopsy forceps according to any one of claims 1 to 4, wherein an opening end portion of the second forceps cup is drawn inside the opening end portion of the first forceps cup by the lead-in portion. .

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