JPH11155806A - Endoscope - Google Patents

Abstract

PROBLEM TO BE SOLVED: To bend only a tip side by a small bending radius and to perform bending in an opposite direction side without any influence given by limiting the bending of at least one direction from a roughly linear state in the rear end area of a bent part, and permitting larger bending without placing no limits on bending in a tip area. SOLUTION: The bent frame 15c of a bent tip side area is rotated until the end surfaces of the respective notched parts of adjacent bent frames 15c are brought into contact. Thus, the tip side area portion is largely bent in any of up and down directions to reach a specified angle. The bent frame 15a of a rear side area portion is rotated until the end surfaces or the butted ends of the respective notched parts of bent frames 15d are brought into contact. Thus, the rear end side area portion is largely bent to reach a specified angle in the same upward direction of the tip side area portion. On the other hand, when the bent parts are in a linear state, since the bent frame 15d is butted on the butted parts of the adjacent ones, the rear end side area portion is not bent downward. In other words, this portion is controlled in a linear state.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an endoscope having an improved structure of a curved portion in an insertion portion.

[0002]

2. Description of the Related Art In general, a flexible endoscope has a flexible insertion portion inserted into a body cavity, and a bending portion which can be operated to bend is provided in a part of the insertion portion. As a bending portion in this type of endoscope, for example, one shown in Japanese Utility Model Publication No. 7-37601 is known.

The bending portion of a general endoscope has the following structure. That is, a plurality of node rings are linearly arranged in the axial direction of the insertion portion, and the adjacent node rings are pivotally connected to each other by rivet pins to connect the node rings. Further, a pair of bending operation wires for bending the bending portion are disposed in the insertion portion of the endoscope at upper and lower portions and left and right portions. Then, the bending operation wire is pulled by the bending driving operation at the proximal operation portion connected to the base end portion of the insertion portion, whereby each node ring rotates in the direction of pulling around the rivet pin, and is adjacent to the bending operation wire. The node rings are able to bend as a whole until the edges contact each other.

Usually, in a small-diameter endoscope for observing the inside of the bladder or uterus, the angle at which the curved portion actually curves in the bladder or uterus is about 200 degrees upward and 1 degree downward.
It is common to bend to about 00 degrees. In this case, the bending portion is designed to determine the number of bending pieces in accordance with the maximum bending angle, that is, the maximum angle of upward bending. Therefore, the entire length of the bending portion is involved in both the upper and lower bending, and when the small bending is performed downward, the bending portion is bent over the entire length. For this reason, the bending is performed in a considerably long range, and the bending radius becomes extremely large. In other words, even if an attempt is made to curve downward at a small bending angle, the distal end portion of the endoscope insertion section will be bent in a large arc. As a result, when observing a narrow space such as the bladder or the uterus, there is an inconvenience that the distal end portion of the endoscope insertion portion immediately hits the organ wall.

Therefore, the bending portion of the endoscope disclosed in Japanese Utility Model Publication No. 7-37601 is modified by changing the notch amount of the contacting edge portion between the adjacent front and rear bending pieces. The bending piece is formed so that the region on the front end side can be bent at a larger angle than the region on the rear side (base end side). In addition, the actual opening 51-14
In the bending portion of the endoscope disclosed in Japanese Patent No. 1088, the notch amount of the lower portion of the abutting end face of each bending piece is smaller than the notch amount of the upper portion so that the upper and lower curves have a desired curved shape, respectively. It is formed small.

In Japanese Patent Publication No. H8-17766, a hardening material is filled in a part of a protective net covering a curved piece from a base end side to a predetermined position in a circumferential direction to partially harden. A configuration is shown in which the curvature is changed so as to limit the curvature in this region.

[0007]

Problems to be Solved by the Invention
In the configuration disclosed in Japanese Unexamined Patent Application Publication No. 51-141088 or Japanese Utility Model Application Laid-Open No. 51-140088, if a relatively large bending operation is performed during the bending operation of the bending portion, the distal end portion of the bending portion is certainly used as a base. It bends more than the end portion, resulting in a smaller radius of curvature. However, when the pulling force from the bending operation wire acts on the bending pieces during the bending operation of the bending portion, the moment applied to the rivet pin serving as the rotation axis of the bending pieces is larger on the base end side than on the distal end side. For this reason, in the initial stage when the bending operation is started, the endoscope first rotates from the base end side, and as a result, the distal end portion of the endoscope insertion portion largely moves and shakes, and is eventually narrow The desired effect cannot be obtained in the body cavity.

[0008] In the configuration disclosed in Japanese Patent Publication No. H8-17766, the movement of the bending piece on the base end side at the beginning of the bending operation is limited by filling the protective net with a hardening material. However, since the protective net itself is filled with a hardening material, each time the bending operation is performed regardless of the bending direction, the hardening material repeatedly receives a tensile force or a compressive force, and as a result,
With repeated use, the effect of the hardening material is weakened, and the material gradually curves from the base end. Further, when the bending operation is performed to the side opposite to the filling side, the hardening material hinders the elongation of the protection net (the movement of the wire), so that there is a disadvantage that the amount of bending force is increased.

The present invention has been made in view of the above problems. In the case of bending to one side, only the tip side is always bent with a small bending radius, and in the case of bending in the opposite direction, the bending is performed without any influence. It is an object of the present invention to provide an endoscope having a curved portion.

[0010]

According to the present invention, an operation section is connected to a base end side of an insertion section to be inserted into a body cavity, and a bending section is provided on the insertion section. In the endoscope configured to bend the bending portion by operation, the bending portion has a distal side region portion and a proximal side region portion, and the distal side region portion has at least a substantially linear reference state. It is possible to bend in two directions, and at least one of the at least two directions in the proximal region.
On the direction side, the configuration was such that bending from a substantially linear reference state was limited. Therefore, in the bending to one side, only the tip side is always bent with a small bending radius, and in the bending in the opposite direction, it is bent without any influence.

[0011]

[First Embodiment] FIGS. 1 to 6
A first embodiment of the present invention will be described with reference to FIG. (Configuration) FIG. 1 shows an endoscope 1, which has an insertion section 2 and an operation section 3. The operation section 3 is provided with an eyepiece section 4, a forceps insertion port section 5, and a bending operation lever 6, and a light guide cable 7 is connected thereto. The insertion portion 2 includes a tubular flexible portion 11 and a tubular curved portion 12 connected to the distal end thereof.
And a tip component 1 provided at the forefront of the curved portion 12
Although not shown, an image transmission fiber, an illumination fiber, a tube for a forceps insertion channel, and the like are inserted therein, and these are fixed to the distal end member 13 at the distal end side.

Next, the configuration of the bending portion 12 will be described. As shown in FIG. 2, a plurality of substantially ring-shaped bending pieces (node rings) 15 are sequentially arranged in series in the bending section 12 along the axial direction of the insertion section 2. Although not shown in the figure, the outer periphery is covered with a metal mesh tube and an outer tube.

The frontmost end of the bending piece 15 is a front end piece 15a which is fitted and fixed to the member of the front end forming section 13, and the rearmost end of the bending piece 15 is a flexible section 11a.
Is a final piece 15b that is fitted and fixed to the tip member. A plurality of bending pieces 15 in the distal side region of the bending portion 12 are bidirectional bending pieces 15c, and a plurality of bending pieces 15 in the proximal side region are one-way bending pieces between the distal piece 15a and the final piece 15b. It is a piece 15d. Further, these bending pieces 15 are linearly arranged in the axial direction of the insertion portion 2, and are connected by pivotally connecting the adjacent edges of the adjacent bending pieces 15 with rivet-shaped shaft pins 16. .

FIG. 3 shows the bending piece 15c, and FIG. 4 shows the bending piece 15d. These bending pieces 15c, 15
As for d, ear-shaped connecting portions 18 are provided at two positions on the left and right sides of the peripheral edge of the distal end edge and the proximal end edge, respectively.
Are formed symmetrically by projecting integrally. Further, ear-shaped connecting portions 18 are integrally formed at two positions on the left and right sides of the peripheral edge of the base piece side edge of the tip piece 15a and the peripheral edge of the tip side edge of the final piece 15b. Are formed symmetrically. Each of these connecting portions 18
Are provided with shaft holes 19, respectively. The shaft pin 16 is inserted into each of the sets of the shaft holes 19 of the corresponding connecting portion 18 of the adjacent bending piece 15 and riveted. Thus, the adjacent bending piece 1
5c, 15d, the leading piece 15a, and the last piece 15b are connected in series. The bending piece 15c constituting the distal end side region portion of the bending portion 12 forms a linear end surface on each of the leading edge and the trailing edge on the upper side and the lower side with respect to the central axis. Notches 21a, 21b, 21c, 2
1d is formed. Each notch 21a, 21b, 21
The end faces of c and 21d are inclined outward toward the center of the bending piece 15c toward the outside, and the extension of the inclined end face is formed to pass through the center of the shaft hole 19.
In addition, these four notches 21a, 21b, 21c,
The position of the outermost end of the peripheral end surface of 21 d passes through the center line of the left and right shaft holes 19, that is, the center line connecting the centers of the left and right shaft holes 19, and is aligned with the longitudinal axis of the curved portion 12. The distance from a plane perpendicular to the surface, that is, the distance to the rotation end is La to Ld, respectively. And usually,
Although the distances La to Ld are set to be equal, they can be set arbitrarily according to the desired bending angle.

On the other hand, with respect to the leading edge and the trailing edge of the bending piece 15d constituting the rear end area of the bending portion 12, the notch 21 similar to the piece member 15c is formed only on the upper side.
a and 21b are provided. There is no equivalent to the notches 21c and 21d below the leading edge and the trailing edge, but instead the abutting portions 22c and 2d.
2d is provided. Both the end portions 23c and 23d of the abutting portions 22c and 22d are connected to the adjacent piece member 15 respectively.
It protrudes in the axial direction toward d. The positions of the tip surfaces 23c, 23d of the abutting portions 22c, 22d pass through the center of the shaft hole 19, that is, the center line connecting the centers of the left and right shaft holes 19, and the longitudinal axis of the curved portion 12 thereof. To the position of the plane perpendicular to. When the bending portion 12 is in a straight line, the bending pieces 15d are arranged so that the abutting portions 22c and 22d abut against each other, although the bending piece 15d is adjacent to the bending piece 15d.

Two bending operation wires 24a and 24b are disposed inside the bending portion 12 at vertical positions about 90 degrees from the connecting portion 18 about the axis of the insertion portion 2. ing. The distal ends of the bending operation wires 24a and 24b are fixed to the distal end piece 15a by brazing or the like, and the base ends of the bending operation wires 24a and 24b are driven by a bending operation lever 6 provided on the operation section 3. It is connected to a mechanism (not shown). When one of the bending operation wires 24a and 24b is selected and towed in accordance with the bending driving operation of the music operation lever 6 of the hand side operation unit 3, each bending piece 15 is towed about the shaft pin 16 as a result. Is turned in the direction of

In the present embodiment, description of general components of the actual endoscope 1 is omitted in order to briefly describe the characteristic portions of the present invention. (Operation) When the bending operation lever 6 is operated to pull one of the predetermined bending operation wires 24a and 24b corresponding thereto, the pulled bending operation wire 24 is pulled.
a, 24b are fixed to the bending portion 12a.
, And at this time, the bending pieces 15 rotate around the shaft pins 16 due to the rotational moment generated around the shaft pins 16.

In this case, regarding the bending pieces 15c constituting the distal end side region of the bending portion 12, the notches 21a, 21b, 21c, 21d of the adjacent bending pieces 15c.
Rotate until the end faces of abut on. As a result, the bending portion 12
Can be greatly curved up to a predetermined angle in any of the upper and lower directions.

As for the bending piece 15d constituting the rear end side area of the bending portion 12, the end faces of the notches 21a and 21b or the abutting portions 22c and 22d of the adjacent bending pieces 15d abut. Rotate up to. As a result,
The rear end region of the bending portion 12 can be largely bent upward to a predetermined angle similarly to the front end region of the bending portion 12. On the other hand, when the bending portion 12 is in a straight line in the rear end side region of the bending portion 12, the bending piece 15d is positioned adjacent to the bending piece 15d.
Since 2c and 22d abut, the rear end side region cannot be bent downward. That is, the linear state is suppressed.

Incidentally, the rotational moment generated around the shaft pin 16 is generated by connecting the last piece 15b farthest from the position where the distal ends of the bending operation wires 24a and 24b are fixed and the bending piece 15b one point ahead. It becomes largest around the shaft pin 16 which is located. Therefore, the bending portion 12 bends sequentially from its proximal end.

Here, as shown in FIG. 2, the upper side of the bending portion 12 is provided with notches 21a, 21
1b, when curved upward,
It curves sequentially from the last piece 15b side. In this case, the strength and operational feeling are not different from those of the conventional endoscope. On the other hand, the bending piece 15b in the region on the base end side of the bending portion 12
Are the tip surfaces 2 of the abutting portions 22c, 22d of the adjacent bending pieces 15d when the longitudinal axis of the bending portion 12 is in a straight line.
Since 3c and 23d are in contact, the downward bending operation is prevented. That is, even if a downward bending operation is performed on the bending portion 12, the bending portion 12 does not bend in the proximal region, and only the distal region performs a downward bending operation.

FIG. 5 shows such a situation, in which the bending portion 12 bends only over the entire length and over the entire length, and the downward bending bends only slightly at the distal end region. Here, the broken line shows the curved shape of the conventional endoscope for reference.

FIG. 6 shows the present embodiment applied to a flexible cystoscope. In the figure, a broken line indicates an insertion portion 2 of the conventional endoscope 1.
Shows the situation. In the bladder 30, the internal urethral opening 3
When the distance between the ureteral opening 1 and the ureteral opening 32 is relatively short, the conventional endoscope has a large downward radius of curvature, so it is too close to the ureteral opening 32 and is located within the visual field of the endoscope 1. Although it cannot be accommodated, according to the present embodiment, when the bending portion 12 is bent downward, only the distal end region of the bending portion 12 is intensively bent small, and observation of a lower adjacent portion is performed. Can be easily performed.

[Second Embodiment] A second embodiment of the present invention will be described with reference to FIG. (Configuration) The present embodiment relates to a modified example of the bending piece 15d constituting the rear end side area of the bending portion 12. The positions of the tip surfaces 23c, 23d of the abutting portions 22c, 22d pass through a center line passing through the center of the shaft holes 19 and are distances ΔL from a surface perpendicular to the longitudinal axis of the curved portion 12 thereof.
Is smaller than any of the distances La, Lb, Lc, and Ld, and when the bending portion 12 is in a straight line, the bending piece 15d is brought into contact with the abutting portions 22c, 2 of its adjacent members.
The tip surfaces 23c and 23d of the 2d do not come into contact with each other.
ΔL is formed. The distance ΔL in this case
Is the maximum tolerance width, for example. Other configurations are the same as those of the above-described first embodiment.

(Operation) If the distance ΔL is the maximum tolerance width,
In the rear end side region of the bending portion 12, when the bending portion 12 is in a linear state, the distal end surfaces 23c and 23d of the bending pieces 15 are in contact with each other while the bending portion 12 is kept in a linear state, or the maximum tolerance width. They face each other with a gap by 2Δ.

(Effect) According to this embodiment, even in the worst processing state, when the bending portion 12 is in a straight state, the bending piece 15
The end surfaces of the abutting portions 22c and 22d of d do not contact each other, and the bending portion 12 is not bent. For this reason, it does not assemble in a state where the curve is warped upward.

[Third Embodiment] A third embodiment of the present invention will be described with reference to FIG. (Structure) This embodiment is an example in which the bending piece 15d constituting the rear end side area of the bending piece bending portion 12 is modified. This bending piece 15d has its abutting portions 22c, 22d formed by pin members 35, and the main body member of the bending piece 15d is formed of the same material as that of the bending piece 15c used in the distal end side region. . The pin member 35 comes into contact with the inner surface of the bending piece 15d and is fixedly attached by means such as brazing. The pin member 35 is mounted parallel to the axis of the bending piece 15d, and the protruding tip of the pin member 35 has the same positional relationship as the tip surfaces 23c and 23d of the abutting portions 22c and 22d. That is, they are provided at a position passing through a center line connecting the centers of the left and right shaft holes 19 and perpendicular to the longitudinal axis of the curved portion 12 or at a slight interval. The curved portions 12 are in a straight line, and the adjacent pin members 35 do not abut each other.

(Effect) In the bending piece 15d of this embodiment, since the abutting portions 22c and 22d are attached to the main body member of the bending piece 15d later, the base itself of the bending piece 15d is used for the front end region of the bending portion 12. The pieces 15c can be shared, and the cost can be reduced.

Although each of the above embodiments has been described in connection with a two-way curve, the present invention may be applied to an endoscope having a four-way curve. [Fourth Embodiment] A fourth embodiment of the present invention will be described with reference to FIGS. (Configuration) In this embodiment, the insertion portion 2 of the endoscope 1 described above is used.
7 is a modification of the structure near the tip in FIG. FIG. 9 shows a portion near the distal end of the insertion section 2.
The distal end portion 13 has a main body member 41 made of metal and a resin cover member 42 bonded and fixed to the distal end portion. A distal end piece 15a is fixedly attached to the base end portion of the main body member 41 by bonding or the like. Also, the main body member 4
1 is provided with a plurality of through holes 47 for inserting and fixing the image guide 43, the light guide 44, the lens 45, the channel member 46, and the like, respectively. An opening 47b having a larger diameter than the distal end portion 47a is provided at the base end side of the through hole 47 into which the channel member 46 is inserted.

The distal end portion 46a of the channel member 46 is formed to have a thickness t1, and at a position corresponding to the opening 47b, a transition portion 46b is formed in which the thickness increases from t1 to t2, which is thicker. The portion 46c closer to the base end than the transition portion 46b is extended while maintaining the thickness t2,
It is guided to the operation unit 3 of the endoscope 1 and is connected to a forceps insertion port 5 provided in the operation unit 3. A groove 48 for preventing buckling is provided on a surface of a portion of the channel member 46 corresponding to the curved portion 12. The groove 48 is formed in an annular shape over the entire circumference or one circumference, and forms a wrinkle on the outer surface of the channel member 46 to give flexibility to the channel member 46. still,
The groove 48 may be formed in a spiral shape.

Further, one or a plurality of flat portions 49 are formed in the outer surface of the distal end portion of the main body member 41 at positions not interfering with the through holes 47.
Further, the cover member 42 is provided with a protruding portion 50 which protrudes from the base end thereof and is located at a position where the flat member 49 is fitted. A tapered surface 5 is provided at a position corresponding to the protruding portion 50 on the outer peripheral surface of the distal end side portion of the cover member 42.
1 is provided.

The tapered surface 51 in this embodiment is formed at a portion of the cover member 42 located between the image guide 43 or the light guide 44 and the channel member 46.

(Operation / Effect) The distal end portion 46a of the channel member 46 is inserted into and adhered to the corresponding through hole 47 of the main body member 41. The distal end portion 46a of the channel member 46 is formed thin. Therefore, it is possible to reduce the through hole 47 provided in the main body member 41 for inserting the same, so that it does not interfere with the through hole 47 into which the image guide 43, the light guide 44, the lens 45, and the like are inserted. , Can prevent meat cuts.

Further, since the tapered surface 51 is provided on the outer peripheral surface of the distal end side portion of the cover member 42, the insertion portion 2
However, it is easy to insert into patients. In addition, since the tapered surface 51 is formed at a position corresponding to the protruding portion 50 fitted to the main body member 41, it is possible to prevent the wall thickness from increasing at this position.
Good moldability of the cover member.

The present invention is not limited to the embodiment described above. According to the above description, at least the following items and items obtained by arbitrarily combining the items can be obtained. [Appendix] An operation section is connected to the proximal end side of the insertion section inserted into the body cavity, and a bending section is provided on the insertion section, and the bending section is driven to bend by an operation from the operation section. In the endoscope, the bending portion has a distal region and a proximal region, and the distal region can be bent in at least two directions from a substantially linear reference state. An endoscope having a configuration in which a side region portion is configured such that bending from a substantially linear reference state is restricted in at least one of the at least two directions.

2. The bending portion has a plurality of bending pieces linearly arranged in the axial direction, and the bending pieces pivotally connect the adjacent bending pieces, and at the end of rotation of the adjacent bending pieces, the edge (end face). ) So that the bending pieces in the proximal end region pass through the edge on the side where bending is limited and the center of the pivot axis of the bending piece when the bending portion is substantially straight. 2. The endoscope according to claim 1, wherein the distance between the curved portion and a surface perpendicular to the axis is smaller than that of the edge on the other side, for example, substantially zero.

3. When the processing tolerance of the edge of the bending piece is set to L, the bending piece in the base side region portion has an edge on the side where the bending is restricted when the bending portion is substantially linear, and the bending piece has an edge of the bending piece. 3. The endoscope according to claim 2, wherein a distance from a plane passing through the center of the pivot axis and perpendicular to the axis of the curved portion is L.

[0038]

As described above, according to the present invention, in the rear end region of the bending portion, the bending portion is restricted from bending in at least one direction from a substantially linear state, and in the front end region, the bending is restricted. Is not limited, and can be bent in a larger size, so that only the distal end region portion is bent, and can be bent with a small bending radius. Therefore, it is possible to bend compactly to one side even in a particularly narrow body cavity, and by performing the bending operation effectively, a special operation effect such as no oversight of a lesion can be obtained. In addition, since the bending in the other direction does not affect the strength or the like, the surgeon can operate safely and concentrate on the surgical procedure without feeling uncomfortable.

[Brief description of the drawings]

FIG. 1 is an external side view showing a schematic configuration of an entire endoscope according to a first embodiment.

FIG. 2 is a side view showing a connection structure of a bending piece of a bending portion of the endoscope.

FIG. 3 is a side view of a bending piece used for a distal end region of the bending portion.

FIG. 4 is a side view of a bending piece used for a rear end side region of the bending portion.

FIG. 5 is an explanatory diagram of a bending state of the bending portion.

FIG. 6 is an explanatory diagram of one use state of the endoscope.

FIG. 7 is a side view of a bending piece used for a rear end side region of a bending portion of the endoscope according to the second embodiment.

FIG. 8 is a side view of a bending piece used for a rear end side region of a bending portion of the endoscope according to the third embodiment.

FIG. 9 is a cross-sectional view of a vicinity of a distal end of an insertion section of an endoscope according to a fourth embodiment.

FIG. 10 is an exploded perspective view of a distal end portion of an insertion section of an endoscope according to a fifth embodiment.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... endoscope, 2 ... insertion part, 11 ... flexible part, 12 ... bending part, 15 ... bending piece.

Claims (1)

[Claims] An operating portion is connected to a proximal end of an insertion portion to be inserted into a body cavity, and a bending portion is disposed on the insertion portion, and the bending portion is driven by an operation from the operation portion. In the endoscope, the curved portion has a distal region portion and a proximal region portion,
In the distal region, a substantially linear reference state can be bent in at least two directions. In the proximal region, at least one of the at least two directions is substantially linear. An endoscope having a configuration in which a curvature from a front is limited.