JPH0458978B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a stone crushing forceps used for crushing a calculus generated within a body cavity.

[Technical background of the invention and its problems]

Stones that occur in organs such as the biliary tract or bladder have a negative impact on patients. This is especially true for enlarged stones.

Therefore, as a treatment for this, it has been conventionally performed to use forceps for crushing stones to crush the stones formed in the body cavity and expel or remove them from the body.

This type of forceps for stone fragmentation is equipped with a foreign body grasping basket made of a plurality of elastic wires at the tip of the operating wire, and the foreign body grasping basket is attached together with the operating wire to a flexible forceps having a hard part at the tip. It is inserted into the sheath and the operating wire advances and retreats from the rear end side.The foreign body grasping basket protrudes from the tip of the flexible sheath and grasps the stone. The basket is shrunk to smaller pieces.

Incidentally, such stone fragmentation forceps are provided with an operating section for opening and closing the foreign body grasping basket. Conventionally, such operation parts were manufactured using the
As shown in No. 34810, a slider mechanism is generally used. Specifically, as shown in FIG. 1, a shaft part b having a continuous finger hook part a is attached to the rear end of a flexible sheath c, a slider d is slidably provided on the shaft part b, This slider d
A structure is used in which the operation wire e is connected to the rear end thereof, and the foreign object grasping basket f is opened and closed by the movement of the slider d.

However, in the case where the operating section is configured with such a slider mechanism, although it is possible to pull the slider d toward the user's hand in order to crush a stone (not shown), the stone may be broken due to the shrinkage of the foreign body grasping basket f. At the moment when the foreign object gripping basket f is pulled into the flexible sheath c, the resistance of the slider d is instantly released and the foreign object grasping basket f is suddenly pulled into the flexible sheath c. For this reason, the small stones crushed by the force of the blast are scattered and pose a danger of damaging the walls of the body cavity.

[Purpose of the invention]

The present invention was made in view of the above-mentioned circumstances, and its purpose is to provide forceps for crushing stones that can safely crush stones.

[Summary of the invention]

That is, the present invention connects the insertion section to a deceleration mechanism that decelerates the operating force and outputs decelerated rotation, and the rear end side of the operating wire, and receives the decelerated rotation output from the deceleration mechanism to move the operating wire forward and backward. By constructing a rack that converts the motion into a linear motion along the direction and transmits the motion to the operating wire, the deceleration effect is used to eliminate the rapid movement of the foreign body grasping basket at the moment the stone is crushed.

[Embodiments of the invention]

The present invention will be explained below based on an embodiment shown in FIGS. 2 to 15. Figure 2 shows the overall structure of the forceps for stone fragmentation, in which 1 indicates the forceps body, 2
3 is a flexible sheath, and 3 is an operating section. Forceps body 1
A foreign object grasping basket 5 is provided at the tip of a long operating wire 4. Specifically, the foreign object grasping basket 5 connects both ends of a plurality of elastic wires 6 with a leading end tip 7a and a trailing end tip 7b, and each elastic wire 6 is formed with, for example, two bent portions 7. A basket-shaped expandable basket is constructed by using the same. The rear end side of each elastic wire 6 extends long from the rear end tip 7b, and one of the elastic wires 6 extends longer than the other elastic wires 6. The wire portion from 7b onwards constitutes the operation wire 4. Also, in the middle of the operation wire 4,
The long elastic wire 6 is connected to another elastic wire 6...
A locking body 9 is provided which connects the ends of the two and serves as a locking part.

On the other hand, the flexible sheath 2 includes, for example, a long tightly wound coil 11 covered with a covering material 10, and an insertion passage 12 into which the foreign object grasping basket 5 or the operating wire 4 can be inserted. It consists of A hard part 13 is provided at the tip of the tightly wound coil 11, and a base 14 having a threaded part on the outer periphery is provided at the rear end. However, while the flexible sheath 2 allows the insertion of the foreign object grasping basket 5 together with the operating wire 4 from the rear end side, the foreign object grasping basket 5 can be freely protruded and retracted from the tip of the hard part 13. It's becoming like that. Note that 15 is a protective member that covers the vicinity of the rear end of the closely wound coil 11 on the proximal side of the flexible sheath 2.

Next, the operation section 3, which is the main part of the present invention, will be explained. Note that FIG. 3 shows the rear surface of the operating section 3, and FIGS. 4 to 7 show each part showing the internal mechanism of the operating section 3.

In the figure, reference numeral 16a denotes an operating section main body formed by overlapping a rack casing 16 and a gear case 17. A rack 18 is housed within the rack casing 16, and a speed reduction mechanism 19 is housed within the gear case 17 and the rack casing 16, respectively. Before explaining the deceleration mechanism 19, the structure around the rack 18 will be explained. The rack 18 has a shaft-like structure with a plurality of rack teeth 18a arranged linearly in parallel on the outer surface. And this rack 18
A through hole 20 is provided in the interior thereof in the axial direction. On the other hand, a rack running path 21 is formed in the rack casing 16 along the longitudinal direction of the rack casing 16, the rear end of which opens at the rear of the rack casing 16. The rack 18 is slidably accommodated within this rack travel path 21. Also, rack casing 1 of rack 18
A locking door 22 is pivotally supported on the rear end surface exposed at the rear of the rack casing 6 so as to be openable and closable with respect to the opening of the through hole 20, while a locking door 22 is pivotally supported on the rear end surface exposed at the rear of the rack casing 16, as shown in FIG. The base 14 of the flexible sheath 2 communicates in series with the through hole 20 of the rack 18 via the through hole 24 and the front end of the rack running path 21.
A fixed ring portion 25 is provided that can be connected to. Therefore, the flexible sheath 2 through which the forceps body 1 is inserted can be connected to the operating section 3, and the operating wire 4 can be sequentially inserted into the fixed ring section 25, the through hole 24, and the through hole 20. By locking the locking body 9 to the locking door 22, the rear end side of the operating wire 4 and the rack 18 are connected.
Both can be connected along the forward and backward direction of the operating wire 4. As shown in FIG. 13, the locking door 22 has a slit 26 that prevents the locking body 9 from passing through, and a recess 27 that fits into the locking body 9 to prevent it from moving inadvertently. A locking portion 28 is provided. Further, 29 indicates a pin for pivotally supporting the locking door 22.

Next, the reduction mechanism 19 is constructed such that a driven shaft 30 extending over the rack casing 16 is rotatably housed in the center of the large diameter part of the gear case 17, and a rack casing 16 is provided in the center of the small diameter part of the gear case 17. A drive-side shaft 31 extending over the entire length is rotatably attached. The driven shaft 30 and the driving shaft 31 are both arranged in a direction perpendicular to the rack 18. Then, the driven side shaft 3
A small-diameter pinion gear 32 that engages with the rack teeth 18a of the rack 18 is provided on the shaft portion located inside the rack casing 16 of No. 0, and a large-diameter gear 33 is installed on the shaft portion located within the large-diameter portion. . Further, a small diameter gear 34 that engages with the large diameter gear 33 is provided on the shaft portion located at the small diameter portion of the drive side shaft 31.
and the gear case 1 of the drive side shaft 31.
A handle 35 is provided at the end protruding from the handle 35, and the operating force applied by a person from the handle 35 is decelerated between the gears 34, the gear 33, and the pinion gear 32, so that the rotation is decelerated from the pinion gear 32. I am trying to output the following. Of course, the rack 18 slides along the advancing and retreating direction of the operating wire 4 due to the engagement between the pinion gear 32 and the rack teeth 18a, and the rack 18 converts the decelerated rotation into linear motion and transmits it to the operating wire 4. In other words, the foreign object grasping basket 5 can be opened and closed.

Therefore, when using the stone crushing forceps configured as described above to dispose of a stone in the bile duct, for example, the forceps body 1 is first attached to an endoscope (not shown).
It starts with assembling.

That is, as shown in FIG. 8, for example, a tube sheath 41 that is long and has a small outer diameter is used to inject a liquid such as a contrast medium, and is inserted into the foreign object grasping basket 5 or the operation wire 4. A gripping part 43 having an operating pipe 42 protruding from the front part is inserted into the rear stage of the tube sheath 41 from the rear end side of the operating wire 4 and is fixed onto the operating wire 4. Note that 44 is an injection port provided at the rear of the tube sheath 41. At this time, the tip of the operating pipe 42 is connected to a locking body 9 as shown in FIG.
The gripping part 43 is positioned by fitting into a recess 45 provided in the gripping part 43, and the operating wire 4 is held between both a screw-in knob 46 and a holding member 47 provided in the gripping part 43, as shown in FIG. ing.

Then, the forceps body 1 combined with such a tube sheath 41 is inserted into the forceps channel of the endoscope.
The foreign object grasping basket 5 is inserted into the tube sheath 41 in a retracted state. It should be noted that this operation is performed because the forceps body 1 can be easily inserted into the endoscope.

Thereafter, the insertion section of this endoscope is inserted into the body cavity, and the distal end of the insertion section is inserted into the bile duct through the duodenal papilla. When a stone 50 is found with the endoscope, the grasping part 43 is moved forward to cause the foreign body grasping basket 5 to protrude from the tip of the tube sheath 41, and the elastic wires 6 of the foreign body grasping basket 5 are opened. The stone 50 is taken into the foreign body grasping basket 5 through the gap. Thereafter, the captured stone 50 is grasped by the foreign object grasping basket 5 by retracting the grasping member 43.

After grasping the calculus using the tube sheath 41, the next step is to attach the large diameter flexible sheath and the operating section 3.

First, the tube sheath 41 is moved from the operation wire 4 whose movement is restricted by grasping the stone 50.
and remove the endoscope. Next, the flexible sheath 2 is inserted using the operating wire 4 remaining in the body cavity as a guide.
is inserted into the body cavity with the hard part 13 first. Here, the operating section 3 with the locking door 22 of the rack 18 opened.
Prepare. Then, the operating portion 3 is inserted through the rear end portion of the operating wire 4 extending from the base 14 of the flexible sheath 2. That is, the fixed ring part 2 of the operating part 3
5. Insert the operating wire 4 into the through hole 24 and then into the through hole 20 of the rack 18 in this order. Thereafter, the fixed ring part 25 of the operating part 3 and the base 14 of the flexible sheath 2 are connected by screwing as shown in FIG. The locking body 9 is pulled out, the locking door 22 is closed, and the locking body 9 is fitted into the recess 27 on the locking door 22 through the slit 26 as shown in FIG. The overall configuration of the stone-crushing forceps assembled in this manner is shown in FIG. 11.

As a result, as shown in FIG.
The flexible sheath 2 and the operating section 3 are disposed in this order after the foreign object grasping basket 5 which has been grasped. After that, if the handle 35 is slowly rotated clockwise, the rack 18 is slid rearward by the rotation reduced by the speed reduction mechanism 19, and the operating wire 4
pull. In this manner, the concretion 50 is tightened by the contraction of the foreign body grasping basket 5, and the concretion 50 is crushed into small pieces as shown in FIG.

Here, in the case of such crushing, conventionally, 5 stones were
It has been pointed out that the moment the foreign object grasping basket 5 is crushed, the small stones 50 are scattered, but this invention can solve this problem.

That is, the rack 18 that pulls the operating wire 4 is driven by the reduced operating force from the deceleration mechanism 19. This means that the amount of backward displacement of the rack 18 and the operating wire 4 is extremely small relative to the applied operating force. Therefore, even if the resistance is released when the calculus 50 is crushed, the foreign object grasping basket 5 will not move rapidly due to the deceleration effect, that is, it will not be suddenly drawn into the flexible sheath 2. Therefore, the finely crushed stones 50 are not scattered by the movement of the foreign object grasping basket 5.

Therefore, the stone 50 can be safely crushed while avoiding the risk of damage to the body cavity wall. Moreover, with such a reduction mechanism 19, it is easy to
In terms of force, the mechanism that drives Rack 8 amplifies the applied operating force and transmits it to Rack 18.
It has the advantage that a large crushing force can be obtained with a light force, and even hard stones 50 can be easily crushed.

Further, the present invention is not limited to the above-mentioned embodiment, but may be modified to other embodiments shown in FIG. 16, for example.

That is, what is shown in FIG. 16 is the drive side shaft 3.
1 is provided with a ratchet mechanism 53 consisting of a reversal prevention gear 51 and a stopper 52 that meshes with the reversal prevention gear 51 to serve as a non-return mechanism, and is intended to prevent the handle 35 from rotating in the opposite direction due to resistance during stone crushing. It is.

In each of the above-mentioned embodiments, stones are crushed using human power, but stones may be crushed using a drive source such as a motor instead of human power. Further, in the embodiment described above, the same wire was used to construct the operating wire 4 and the basket for grasping a foreign object, but as in another embodiment shown in FIG. The basket 5 may also be configured. Specifically, in the device shown in FIG. 7, the operating wire 4 is constructed of an elastic wire having a length up to the rear end tip 7b, and the foreign object grasping basket 5 is constructed as follows.

That is, one end of a plurality of elastic wires 6, for example, two elastic wires 6 other than the operating wire 4, is fixed to the rear end tip 7b, and the other end is folded back at the front end tip 7a and then attached to the rear end tip again. 7b
The other end extends from the rear end tip 7b to the retaining body 9 so as to return to the position shown in FIG.

〔Effect of the invention〕

As explained above, according to the present invention, by reducing the amount of retreat of the operating wire due to the deceleration effect, it is possible to eliminate the rapid movement of the foreign object grasping basket at the moment the stone is crushed.

Therefore, it is possible to prevent stones from scattering due to rapid movement of the foreign object grasping basket, and it is possible to safely crush stones. Moreover, it has the advantage of being able to obtain a large crushing force with a light force by adopting a speed reduction mechanism, and even hard stones can be easily crushed.

[Brief explanation of the drawing]

Figure 1 is a cross-sectional view of a conventional stone crushing forceps;
2 to 15 show an embodiment of the present invention, in which FIG. 2 is an exploded view of the forceps for stone fragmentation, FIG. 3 is a rear view of the operating section, and FIG. 4 is a view of the operating section shown in FIG. 2.
A sectional view taken along the line, Figure 5 shows the operating section in Figure 2.
A cross-sectional view along the line, Figure 6 is the operating section in Figure 3.
A cross-sectional view along the line, Figure 7 is the operating section in Figure 3.
8 is a sectional view showing a structure in which a tube sheath is combined with a basket for grasping a foreign object or an operating wire, FIG. 9 is an enlarged sectional view of the area around the locking body, and FIG. FIG. 11 is a cross-sectional view showing the assembled stone fragmentation forceps, FIG. 12 is a cross-sectional view showing the connection structure between the flexible sheath and the operating section, and FIG. 13 is an enlarged cross-sectional view of the parts. FIG. 14 and FIG. 15 are side views showing the state of stone crushing using stone crushing forceps; FIG. 16 is a perspective view showing another embodiment of the present invention; FIG. FIG. 17 is a sectional view showing another embodiment of the present invention. 2... Flexible sheath, 3... Operating section, 4... Operating wire, 5... Foreign object grasping basket, 13... Hard part,
18...Rack, 19...Reduction mechanism.

Claims (1)

[Claims] 1. A foreign object grasping basket made of a plurality of elastic wires is provided at the distal end of a manipulation wire that is inserted into a flexible sheath having a hard part at the distal end, and this foreign matter grasping basket is inserted together with the manipulation wire at the distal end. In the stone-crushing forceps, which are inserted into a flexible seal having a hard part, and the operating wire is moved forward and backward by the operating part from the rear end side, the operating part is composed of a plurality of gears with different numbers of teeth, and the operating force is controlled by the operating force. a deceleration mechanism that decelerates and outputs decelerated rotation; and a deceleration mechanism that is connected to the rear end side of the operating wire and receives the decelerated rotation output from the deceleration mechanism and converts it into a linear motion along the advancing and retreating direction of the operating wire. A forceps for crushing stones, characterized in that the forceps include a rack for transmitting information to an operating wire.