JP3390041B2 - Forceps - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a forceps for grasping or cutting tissue, for example, for use in endoscopic surgery. 2. Description of the Related Art Japanese Unexamined Patent Publication No. Hei 4-2 is used as forceps (scissors) for grasping and cutting tissue used in endoscopic surgery.
No. 46344 is known. This forceps comprises a forceps body that can be opened and closed at a distal end thereof, a forceps body provided with an operation unit at a base end, and a driving member provided on the forceps body that moves back and forth by operating the operation unit to open and close the forceps unit. It is configured. [0003] gripper is formed by a rotatable pair of forceps members the pivot pin as a fulcrum, the cam groove is provided on the rear end portion of the forceps members. An engagement pin is protruded from a distal end portion of the drive member driven forward and backward by the operation portion. The engagement pin is engaged with the cam groove, and the forceps member is pivotally supported by the forward and backward movement of the drive member. It can be opened and closed with a pin as a fulcrum. The forceps disclosed in German Utility Model No. 8809501 has a forceps member which is rotatable around a pivot pin at a tip end of a forceps main body.
A movable guide member is provided. An extension is provided at the rear end of the forceps member, and the extension is engaged with a guide channel provided in the guide member. The forceps member is opened and closed via the extension by moving the guide member forward and backward by the operation member. [0005] However, the former forceps among the forceps structured as described above has a considerably large force applied to the cam groove when cutting tissue or gripping a treatment tool or the like. Is added. Therefore, in order to give the forceps member having the cam groove sufficient strength, the shape and dimensions around the cam groove are increased. As a result, if the forceps member is to be opened widely, the rear end of the member will protrude greatly outside the diameter of the insertion portion as the forceps body. In particular, since this type of forceps is used by being inserted into a tubular tracar, the rear end of the forceps member that has protruded outside is caught by the front end of the tracar, making it difficult to close. Further, since the cam groove is formed in the forceps member requiring hardness, the sliding surface is hard, and the engaging pin for the engaging pin has a small contact area, so that a harder material must be used. This adds to the difficulty of designing and manufacturing. In the latter, when the forceps member is opened, the rear end of the forceps member protrudes greatly beyond the outer diameter of the insertion portion, and has the same disadvantages as the former, and the extension portion is thin and long. Easy to break. In addition, when an unexpected situation is encountered and it is necessary to remove the tracar without being able to close it, the extension portion projects obliquely rearward, so that the tracar is caught by the front end and hardly comes off. At this time, even if the tracar is to be pulled out, the protruding extension will hinder the pulling out. Further, since the width (thickness) of the extension portion is changed, a gap is generated in combination with the guide channel, and the movement of the forceps member tends to be loose. Further, a forceps member is used as a forceps opening / closing mechanism.
Although there is an articulated link mechanism, the link protrudes from the insertion portion when the forceps member is opened, and cannot be removed from the tracar if it is open. In addition, 4
Due to the characteristics of the node link mechanism, the force that can be generated at the distal end when the forceps member is completely closed is minimized, which is extremely disadvantageous when a function as scissors for cutting tissue is provided. The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a forceps having a structure capable of reducing the shape and size of a forceps member. [0011] In order to achieve the above object, the present invention provides an insertion portion to be inserted into a subject, a pivot portion provided at a distal end of the insertion portion, A forceps member rotatable around the pivot portion, a treatment section provided at a distal end of the forceps member, a projection provided closer to the forceps member than the treatment section, and the forceps member. Operating means for rotating operation, moving means connected to the operating means and movable with respect to the insertion portion in response to operation of the operating means, and engaging with the projection provided on the moving means The forceps having a groove which is capable of rotating the forceps member by moving the protrusion in accordance with the movement of the moving means. By inserting the insertion portion into the subject and operating the operating means at a desired position in the subject to move the moving means, the protrusions which engage with the grooves provided in the moving means are inserted into the grooves. To move the forceps member provided with the projection around the pivot provided on the insertion portion. Embodiments of the present invention will be described below with reference to the drawings. FIGS. 1 to 6 show a first embodiment, and FIG. 2 shows an entire endoscope forceps. The forceps consist of a forceps part 1, an insertion part 2 as a forceps main body, and an operation part 3. It is configured.
The forceps unit 1 includes a pair of forceps members 4, 5,
And an opening and closing mechanism 6 for opening and closing the forceps members 4 and 5. The insertion section 2 comprises a tubular sheath 7 and a driving member 8 which is inserted into the inside thereof so as to be able to advance and retreat, and is connected to the opening / closing mechanism 6. The operation section 3 comprises a pair of handles 9 a and 9 b that can be rotated about a pivot pin 9 as a fulcrum, and a connecting member 10 connected to the driving member 8. The forceps are inserted into a patient's abdominal cavity via a tracal or the like, and the handles 9a and 9b are opened and closed by the operator, whereby the forceps members 4 and 5 of the distal end portion 1 are opened and closed, and organs and Blood vessels, peritoneum and other objects can be cut, and when used as grasping forceps or peeling forceps,
By opening and closing the handles 9a, 9b, the forceps members 4, 5 can be opened and closed to grasp or peel off the target. Next, the details of the forceps section 1 and the insertion section 2 will be described with reference to FIGS. 1, 3, and 4. A cylindrical holding member 12 is projected from the distal end of the sheath 7, and Slots 12a are formed in the upper and lower portions of the member 12 along the axial direction. A rear end of a pair of forceps members 4 and 5 constituting the forceps portion 1 is housed in the slot 12a, and an intermediate portion of the forceps members 4 and 5 has a pivot pin 1 as a pivot portion.
3 rotatably supports the holding member 12. Blade portions 4a, 5a are formed on the distal end side of the forceps members 4, 5, and columnar projections 4b, 5b are protruded inside the rear end portion. Further, the blades 4a, 5a of the forceps members 4, 5
a is curved. In this case, it is necessary that the bending directions be different in the upper, lower, left and right directions depending on usability. [0020] The inside of the holding member 1 2 of the base end side is provided integrally with the driving member 8, the connecting member 14 is inserted retractably in the axial direction forming part of the drive member. The distal end 14a of the connecting member 14 has a flat shape, and arcuate cam grooves 14b and 14c are formed on the side surfaces thereof so as to intersect with each other. The cam grooves 14b and 14c are respectively provided with the protrusions 4b and 5b. Are slidably engaged. The cam grooves 14b and 14c are not limited to the arc shape, but may be an arbitrary curve or an inclined straight line. The rear end 14d of the connecting member 14 has a cylindrical shape.
The O-ring 14e is fitted in the middle of the holding member 1
2 is sealed. Further, the width (height) of the front end portion 14a of the connecting member 14 is larger than the diameter of the rear end portion 14d, and the rear end side of the front end portion 14a is formed on a rear end surface 14f projecting outward from the rear end portion 14d. . Accordingly, when the forceps members 4 and 5 are closed, the bottom surface 12b of the slot 12a of the holding member 12 is in contact with the rear end surface 14f of the connecting member 14. In this state, the distal ends of the cam grooves 14b and 14c are kept at a constant distance from the protrusions 4b and 5b and do not come into contact with each other. The distal end 14a of the connecting member 14 is inserted between steps 4c, 5c formed at positions corresponding to the projections 4b, 5b at the rear end of the forceps members 4, 5, and FIG. The positional relationship between the projections 4b and 5b of the forceps members 4 and 5 and the distal end portion 14a of the connecting member 14 inserted between the step portions 4c and 5c is shown. As shown in FIG. 4, the projections 4b and 5b extend in a direction orthogonal to the longitudinal axis of the insertion portion 2, and the projections 4b and 5b are formed in the cam grooves 14b and 14c.
Of the cam grooves 14b, 14
c is formed so as not to contact the tips of the protrusions 4b and 5b. Next, the insertion section 2 and the operation section 3 will be described with reference to FIGS. 5 and 6. The insertion section 2 includes a tubular member 16 and a tubular insulating member 17 fitted on the outside thereof. The driving member 8 is inserted into the tubular member 16 so as to be able to advance and retreat. The rear end of the insertion portion 2 is extended by exposing the tubular member 16 from the insulating member 17, and the exposed portion 16a is inserted into a through hole 9c provided in the handle 9a. An intermediate member 19 is buried between the through hole 9c and the exposed portion 16a of the tubular member 16, and a conical engagement hole 16b is formed in the exposed portion 16a.
The distal end of the fixing member 18 serving as a high-frequency power terminal screwed into and fixed to a is engaged. Although the engagement holes 16b are formed at positions 180 ° apart on the circumference of the exposed portion 16a, they may be formed at intervals of 90 ° on the circumference, or at smaller intervals. Many may be provided. By providing a plurality of engagement holes 16b in this way, the bending direction of the forceps members 4a, 5a can be fixed at a desired position. Next, the operation of the forceps configured as described above will be described. By operating the handles 9a and 9b with fingers, the driving member 8 advances inside the sheath 7, and the connecting member 14 also moves to the distal end side. Connecting member 1
When the cam grooves 14b and 14c provided at the distal end portion 14a of the fourth member 4 advance, the protrusions 4b and 5b
b, 14c, the forceps members 4, 5 are
It rotates in the direction in which it opens relatively with 3 as a fulcrum. Since the cam grooves 14b, 14c are curved, the projections 4b, 5b
Since the contact angle between the cam grooves 14b and 14c is small, a large force can be generated. The same operation is performed when the cam grooves 14b and 14c are linear, but the cam groove 14b and 14c largely move with a short stroke near the fully closed position. A forceps that grips a soft object is safe because the gripping force does not become too large. If the pivot pin 13 is broken, the projections 4b and 5b are
The forceps members 4 and 5 do not fall off because they are caught on the end of 14c. When the forceps members 4 and 5 are fully opened, the contact angle is large, so that the forceps members 4 and 5 can be widely opened with a short stroke.
By changing the shapes of the cam grooves 14b and 14c, it is possible to arbitrarily select how to generate the force. The operation of closing the forceps members 4 and 5 is the reverse of the above-described operation. By operating the handle 9a or 9b with a finger, the driving member 8 retreats inside the sheath 7 and the connecting member 14 is moved to the near side. Go to Tip 1 of connecting member 14
When the cam grooves 14b and 14c provided on the 4a are retracted, the protrusions 4b and 5b slide in the cam grooves 14b and 14c, and the forceps members 4 and 5 are relatively closed with the pivot pin 13 as a fulcrum. Rotate in the direction. By the retreat of the driving member 8, the distal end 14a of the connecting member 14 moves while being sandwiched between the steps 4c, 5c. This prevents the tip portion 14a from rotating around the axis of the insertion portion 2, and prevents the projections 4b, 5b from being inclinedly engaged with the cam grooves 14b, 14c. FIGS. 7 and 8 show a second embodiment, in which the same components as those in the first embodiment are designated by the same reference numerals and their description is omitted. As shown in FIG. 7, the structure of the forceps section 1 is basically the same as that of the first embodiment, but the positions of the cam grooves 14b and 14c are shifted in the front-rear direction (the axial direction of the insertion section 2). FIG. 8 shows the projections 4b, 5b of the forceps members 4, 5.
And a positional relationship between the front end portion 14a of the connecting member 14 inserted between the step portions 4c and 5c. The projections 4b, 5b extend in a direction perpendicular to the longitudinal axis of the insertion portion 2, respectively. Since these projections 4b, 5b both extend beyond the axis, the positions are shifted back and forth so as not to interfere. Is provided. Further, the projections 4b, 5b are formed in the cam grooves 14b,
14c protrudes toward the bottom of the cam groove 14c.
The b and 14c are formed so as not to contact the tips of the protrusions 4b and 5b. As a result, the cam grooves 14b and 14c intersect at one place. Therefore, by the reciprocation of the connecting member 14,
The protrusions 4b, 5b slide in the cam grooves 14b, 14c, respectively. As a result, the forceps members 4 and 5 rotate about the pivot pin 13 as a fulcrum to open and close. Since the two projections 4b and 5b are arranged so as to be shifted in the axial direction as described above, the projection 4
b, 4b can be made longer and the cam grooves 14b, 14c can be made deeper, and the contact area between the protrusions 4b, 4b and the cam grooves 14b, 14c can be increased, so that the durability can be improved. FIG. 9 shows a third embodiment. The same components as those in the first embodiment are denoted by the same reference numerals and description thereof is omitted. A cam groove 14b provided at a tip portion 14a of the connecting member 14,
14c has an open end. It should be noted that the opening is not limited to the front end side, but may be at the rear end side. With this configuration, it is not necessary to insert the forceps members 4, 5 and the connecting member 14 into the holding member 12 in a combined state, so that the assembly is easy. FIG. 10 shows a fourth embodiment, in which the same components as those in the first embodiment have the same reference numerals and description thereof will be omitted.
The projections 4b and 5b are parts different from the forceps members 4 and 5. That is, screw holes 4e, 5e (only one is shown) are formed in the rear end portions of the forceps members 4, 5, and these screw holes 4e, 5e are formed.
The pin members 15 as projections are screwed and fixed to e and 5e, respectively. The pin member 15 is formed of a material having high wear resistance or stainless steel which can be hardened by heat treatment, and has a hard chromium film having a thickness of 10 μm to 30 μm.
It has a Vickers hardness of 800-1000. The coating is made of titanium carbide and titanium nitride by CVD or PVD.
The ceramic coat of the layer may be used. It has a Vickers hardness of 2000-3000. By reducing the wear of the pin member 15 sliding with respect to the cam grooves 14b and 14c,
The durability of the forceps can be improved. Forceps members 4, 5
Since a different material can be used, safety can be enhanced by using a material having high toughness. Since the forceps members 4 and 5 have a plate shape,
Using a stainless steel plate for a spring or a rolled steel plate, it is also possible to produce at low cost by plastic working. FIG. 11 shows a fifth embodiment. The same components as those in the first embodiment are designated by the same reference numerals and the description thereof will be omitted.
FIG. 11 shows a cross section of the forceps member 4. Blade part 4a, polishing surface 4
f, a flank 4g, and the same applies to the forceps member 5. Except for the polished surface 4f, a TiC film 4h and a TiN film 4i on the TiC film 4h are formed on the surface of the substrate. After forming the two layers of coatings 4h and 4i, the hardness and toughness are increased by tempering (quenching and tempering). FIG. 12 shows a sixth embodiment. The same components as those in the first embodiment are denoted by the same reference numerals and description thereof is omitted.
FIG. 12 shows a cross section of the forceps member 4. The entire surface of the base material of the forceps member 4 is covered with a layer of TiC and TiN, and there is no polished surface 4f. Depending on the object to be cut, the strength of contact between the blades may be more advantageous than the sharpness of the blades. This is the case, for example, in the case of a thick muscular layer such as an artery, a tough one such as a muscle or tendon, or a bone or meniscus. Except for the process of attaching a blade by polishing, leaving the film as it is by CVD does not expose the cross section of the film, so it is strong against peeling and is advantageous in cost. FIGS. 13 and 14 show a modification of the forceps. As in the first embodiment, a pair of forceps members 4 and 4 are used.
5 is pivotally supported by a holding member 12 by a pivot pin 13. Cam grooves 4b, 5b are provided at the rear ends of the forceps members 4, 5, respectively. The surfaces of the forceps members 4 and 5 and the connecting member 14
Are coated with TiC and TiN films by CVD. The distal end portion 14a of the connecting member 14 has a flat shape, and the cam grooves 4b, 5b at the rear end portions of the forceps members 4, 5.
Are inserted between the step portions 4c, 5c formed at positions corresponding to. A hole 20 is provided in the distal end portion 14a of the connecting member 14, and a connecting pin 21 is fitted in the hole 20. A hard chrome coating is formed on the surface of the connecting pin 21. The thickness of the coating is between 10 μm and 30 μm. Further, the connecting pin 21 is provided with inclined straight cam grooves 4b, 5b provided at the rear ends of the forceps members 4, 5.
Are engaged with both. The cam grooves 4b, 5b may be curved in an arc shape, and the shape of the cam grooves 4b, 5b may be an arbitrary curve. Therefore, as in the first embodiment, the operating member 8 moves forward by operating the handles 9a and 9b, and the connecting pin 21 also moves to the distal end side via the connecting member 14. As the connecting pin 21 moves in the cam grooves 4b and 5b, the forceps members 4 and 5 rotate in the direction of relatively opening with the pivot pin 13 as a fulcrum. The operation of closing the forceps members 4 and 5 is reverse to the above. When the forceps members 4 and 5 are fully closed, the connecting pin 2
A large force can be generated because the contact angle between 1 and the cam grooves 4b and 5b is small. Even if the fulcrum pin 13 is broken, the forceps members 4 and 5 do not fall off because the connecting pin 21 is caught on the ends of the cam grooves 4b and 5b. When the forceps members 4 and 5 are fully opened, the contact angle is large and the forceps members 4 and 5 can be widely opened with a short stroke.
By changing the shape of the cam grooves 4b, 5b, it is possible to arbitrarily select how to generate the force. The moving of the driving member 8 causes the connecting member 1 to move.
4 moves while being sandwiched between the step portions 4b and 5b. This prevents the tip portion 14a from rotating around the axis of the insertion portion 2, and prevents the connecting pin 21 from being inclinedly engaged with the cam grooves 4b, 5b. As described above, the blades 4 of the forceps members 4 and 5
Since the hard coating is formed on the sliding portion between a and 5a, the blade portion is not deformed due to wear and the sharpness is not deteriorated. In addition, since there is no fear of abrasion, it is possible to apply a large pressing force to cut a tough, hard-to-cut object. It has good conductivity while having the same hardness as alumina ceramic or zirconia ceramic used for surgical scalpels and forceps members. Thereby, hemostasis and coagulation can be performed using high frequency. The color of the titanium nitride coating itself is gold. Therefore, the presence or absence of the coating can be determined at a glance. Further, the state of wear of the coating can be easily identified. Furthermore, since it is deposited on the surface of the base material, the surface immediately after the film is formed is completely matte, has a high antireflection effect, and hardly occurs when observed with an endoscope. The processing temperature at the time of film formation is as high as 1000 ° C. or higher. Therefore, it has heat resistance to withstand the quenching temperature of stainless steel or carbon steel. Furthermore, the temperature of the heat treatment after the formation of the coating can be freely set, and desired hardness and toughness can be obtained. The coating made of TiC and TiN is extremely hard with a Vickers hardness of 2000 to 3000. For this reason, it is hard to be damaged. In addition, in normal cleaning, cleaning can be completed in a short time by rubbing with a large force. As described above, according to the present invention,
A forceps having a structure capable of reducing the shape and size of the forceps member can be provided. [0063]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a longitudinal sectional side view showing a forceps portion of a forceps according to a first embodiment of the present invention. FIG. 2 is a side view of the entire forceps of the embodiment. FIG. 3 is a vertical plan view of a forceps portion of the forceps of the embodiment. FIG. 4 is an exemplary sectional view showing an engagement state between a protrusion and a cam groove according to the embodiment; FIG. 5 is a vertical sectional side view showing the operation unit of the embodiment. FIG. 6 is a sectional view taken along the line AA in FIG. 5; FIG. 7 is a longitudinal sectional side view showing a forceps portion of a forceps according to a second embodiment of the present invention. FIG. 8 is a vertical plan view of a forceps portion of the forceps of the embodiment. FIG. 9 is a longitudinal side view showing a forceps portion of a forceps according to a third embodiment of the present invention. FIG. 10 is a sectional view showing an engagement state between a projection of a forceps and a cam groove according to a fourth embodiment of the present invention. 11 is a sectional view of a forceps member according to a fifth embodiment of the present invention; FIG. 12 is a sectional view of a forceps member according to a sixth embodiment of the present invention; FIG. 4 is a vertical sectional side view in a state where a member is closed. FIG. 14 is a longitudinal sectional side view showing the modified example, with a forceps member opened. [Description of Signs] 1 ... Forceps part 2 ... Insertion part 3 ... Operation part 4, 5 ... Forceps members 4b, 5b ... Projection 8 ... Driving member 13 ... Pivot pins 14b, 14c ... Cam groove

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Claims (1)

(57) [Claim 1] An insertion portion to be inserted into a subject, a pivot portion provided at a distal end portion of the insertion portion, and a forceps member rotatable around the pivot portion as a rotation center. A treatment unit provided at a distal end portion of the forceps member, a projection provided closer to the hand of the forceps member than the treatment unit, an operation unit for rotating the forceps member, and the operation unit A moving means connected to the operating section and movable with respect to the insertion portion in response to the operation of the operating means; and a projection provided in the moving means to engage with the projection, and the projection being moved in accordance with the movement of the moving means. And a groove capable of rotating the forceps member by moving the portion.