WO2017187615A1

WO2017187615A1 - Sheath for flexible manipulator

Info

Publication number: WO2017187615A1
Application number: PCT/JP2016/063428
Authority: WO
Inventors: 裕太藤井; 利博吉井
Original assignee: オリンパス株式会社
Priority date: 2016-04-28
Filing date: 2016-04-28
Publication date: 2017-11-02

Abstract

In order to suppress variation of wire path length to accurately control a manipulator even when the tensile force on the wire passing through a lumen increases, this flexible manipulator sheath (1) is provided with a flexible inside tube (9) having a lumen (8) through which a wire (4) is passed along the longitudinal direction, and a flexible outside tube (10) which is arranged so as to cover the outer peripheral surface of the inside tube (9) and which has higher compression rigidity than the inside tube (9), wherein, on the outer peripheral surface of the inside tube (9), multiple protrusions (11) are provided, spaced in the circumferential direction, with the radially outward tips of said protrusions brought into close contact with the inner surface of the outside tube (11).

Description

Sheath for flexible manipulator

The present invention relates to a sheath for a flexible manipulator.

Resin having a plurality of lumens penetrating in the longitudinal direction of a flexible long material as a sheath used for an insertion portion of a flexible manipulator having a movable portion at the tip of a flexible insertion portion to be inserted into a curved body cavity A manufactured multi-lumen tube is known (for example, see Patent Document 1).
A wire for driving a movable portion provided at the distal end of the insertion portion is disposed through each lumen of the multi-lumen tube.

Japanese Patent No. 4420593

In the sheath of Patent Document 1, when the wire is pulled, the multi-lumen tube is bent or compressively deformed by the frictional force applied from the wire to the inner surface of the lumen, so that the path length of the wire penetrating the other lumen varies. However, there is an inconvenience that the movable part cannot be accurately controlled.

The present invention has been made in view of the above-described circumstances, and can control the manipulator with high accuracy by suppressing fluctuations in the path length of the wire even when the tension applied to the wire penetrating the lumen is increased. An object of the present invention is to provide a sheath for a flexible manipulator.

In one embodiment of the present invention, a flexible inner tube having a lumen that penetrates a wire along a longitudinal direction, and an outer peripheral surface of the inner tube are disposed so as to be more compressive than the inner tube. A plurality of protrusions that are provided on the outer peripheral surface of the inner tube with a radially outer tip closely attached to the inner surface of the outer tube, spaced apart in the circumferential direction. A sheath for a flexible manipulator.

According to this aspect, when the movable portion of the manipulator provided at the distal end is driven by applying tension to the proximal end of the wire penetrating into the lumen, the wire is flexible due to friction between the wire and the inner surface of the lumen. The inner tube is likely to be deformed, but the inner tube is supported by the outer tube with higher compressive strength by closely attaching the protrusion provided on the outer peripheral surface to the inner surface of the outer tube. Deformation is avoided. As a result, even when the wire is pulled, fluctuations in the wire path length are suppressed, and the manipulator can be controlled with high accuracy.

In the said aspect, the said processus | protrusion may consist of the protruding item | line extended in the longitudinal direction of the said inner side tube.
By doing so, the inner tube is supported by the outer tube on the outer tube in a long range along the longitudinal direction, and the variation in the path length can be prevented more reliably.

The protrusion may extend continuously over the entire length of the inner tube.
By doing so, the inner tube is supported by the outer tube over the entire length by the protrusion, and the variation in the path length can be prevented more reliably.

Moreover, in the said aspect, the said processus | protrusion may extend intermittently over the full length of the said inner side tube.
By doing in this way, an inner tube is supported in the range with a projection in an outer tube, and change of a path length can be prevented. The ease of bending can be improved by the intermittent protrusions.

Moreover, in the said aspect, the front-end | tip of the said protrusion may have the cross-sectional shape which consists of a convex curved surface.
By doing in this way, the contact area of the front-end | tip of protrusion and the inner surface of an outer tube can be reduced, and the ease of insertion of the inner tube to an outer tube can be improved.

Moreover, in the said aspect, the said processus | protrusion may have a cross-sectional shape extended incline with respect to radial direction from the outer peripheral surface of the said inner side tube.
By doing so, the protrusion that contacts the inner surface of the outer tube falls in the circumferential direction due to elastic deformation, so that the inner tube is softly supported by the inner surface of the outer tube, and the ease of inserting the inner tube into the outer tube is improved. In addition, the ease of bending of the sheath can be improved.

Moreover, in the said aspect, you may have a cavity in the radial direction inner side of the said protrusion.
In this way, when the protrusion that contacts the inner surface of the outer tube receives a force inward in the radial direction, the cavity disposed radially inward of the protrusion is compressed, and the radial position of the protrusion is reduced in diameter. Displace inward direction. Thereby, the inner tube is softly supported on the inner surface of the outer tube, and it is possible to improve the ease of inserting the inner tube into the outer tube and the ease of bending of the sheath.

Moreover, in the said aspect, the said processus | protrusion may be provided in the helical form twisted around a longitudinal axis.
By doing in this way, the frictional resistance at the time of inserting an inner tube in an outer tube can be reduced, and the insertion ease of the inner tube to an outer tube can be aimed at.

Further, in the above aspect, the inner tube includes a plurality of the lumens, each of the lumens is formed in a spiral shape that twists around the longitudinal axis and does not intersect with each other, and the protrusion has a center line of the inner tube. It may be arranged on the opposite side to each of the lumens.
In this way, tension is applied to the wire, so that a force that deforms the lumen so as to approach a straight line acts on the spiral lumen that penetrates the wire from the wire. Thus, the force is effectively supported by the protrusion located on the opposite side of the lumen, and the movement of the inner tube within the outer tube can be prevented, and the variation in the path length can be more reliably prevented.

Moreover, in the said aspect, the said outer side tube may be a coil tube, and the helical pitch of the said protrusion may be larger than the pitch of the said coil tube.
By doing in this way, it is prevented that a protrusion partly meshes with the unevenness | corrugation of the inner surface of a coil tube, and an inner tube can be reliably supported by the inner surface of an outer tube.

According to the present invention, even if the tension applied to the wire penetrating into the lumen is increased, the manipulator can be controlled with high accuracy by suppressing the fluctuation of the wire path length.

It is a whole lineblock diagram showing a flexible manipulator provided with a sheath for flexible manipulators concerning one embodiment of the present invention. It is a longitudinal cross-sectional view which shows the sheath for flexible manipulators of FIG. It is a cross-sectional view which shows the inner tube with which the sheath for flexible manipulators of FIG. 1 is equipped. It is a perspective view which shows the inner side tube of FIG. It is a cross-sectional view showing a first modification of the inner tube of FIG. It is a cross-sectional view showing a second modification of the inner tube of FIG. It is a cross-sectional view showing a third modification of the inner tube of FIG. It is a perspective view which shows the 4th modification of the inner side tube of FIG. It is a cross-sectional view showing a fifth modification of the inner tube of FIG.

Hereinafter, a sheath 1 for a flexible manipulator according to an embodiment of the present invention will be described with reference to the drawings.
As shown in FIG. 1, the soft manipulator 100 is provided with a sheath 1 for a soft manipulator according to this embodiment, a manipulator 2 provided at the distal end of the sheath 1 for soft manipulator, and a proximal end of the manipulator 2. A drive unit 3 that generates power for operating the manipulator 2 and a wire 4 that transmits the power generated in the drive unit 3 to the manipulator 2 are provided.

The manipulator 2 includes a movable part 5 having one or more joints, and an end effector 6 supported at the tip of the movable part 5.
The drive unit 3 includes, for example, a motor (not shown) and a pulley 7 that transmits the power of the motor to the wire 4.

As shown in FIG. 2, the flexible manipulator sheath 1 according to this embodiment includes a resin-made multi-lumen tube (inner tube) 9 including a plurality of lumens 8 penetrating in the longitudinal direction, and the multi-lumen tube 9. A coil tube (outer tube) 10 penetrating inward is provided.
A wire 4 can be passed through each lumen 8 of the multi-lumen tube 9. Both ends of the wire 4 penetrating the lumen 8 are connected to the manipulator 2 at the distal end of the sheath 1 for the flexible manipulator and the drive unit 3 at the proximal end.

In this embodiment, a plurality of ridges (projections) 11 are provided on the outer peripheral surface of the multi-lumen tube 9 at equal intervals in the circumferential direction as shown in FIG. The ridges 11 are integrally formed as a part of the multi-lumen tube 9 with a resin constituting the multi-lumen tube 9 so that the outer peripheral surface of the multi-lumen tube 9 is raised radially outward. In general, the multi-lumen tube 9 is manufactured by resin extrusion, and the lumen 8 and the ridges 11 are formed straight along the longitudinal direction. The cross-sectional shape of the ridge 11 is, for example, a rectangle.

The operation of the thus configured sheath 1 for the flexible manipulator according to this embodiment will be described below.
According to the flexible manipulator sheath 1 according to the present embodiment, when tension is applied to the wire 4 by the driving unit 3, the flexible multi-lumen tube 9 is caused by friction between the wire 4 and the inner surface of the lumen 8. Even if elastic deformation is attempted, the radially outer tip of the ridge 11 provided on the outer peripheral surface of the multi-lumen tube 9 is in close contact with the inner surface of the coil tube 10, so that the multi-lumen tube 9 is It is supported by the coil tube 10 via.

Since the coil tube 10 has higher compression rigidity than the multi-lumen tube 9, deformation of the multi-lumen tube 9 is suppressed, and fluctuations in the path length of the wire 4 can be prevented. As a result, when a tension is applied to one wire 4, the path length of the other wire 4 varies, and the inconvenience of driving the manipulator 2 in an unintended direction is prevented, and the movable part 5 of the manipulator 2 is accurately There is an advantage that it can be controlled well.

Further, if the entire outer peripheral surface of the multi-lumen tube 9 can be brought into close contact with the inner surface of the coil tube 10, the multi-lumen tube 9 can be more reliably prevented from being deformed. It is difficult to insert the tube 9. According to the flexible manipulator sheath 1 according to the present embodiment, the outer surface of the multi-lumen tube 9 is partially brought into contact with the inner surface of the coil tube 10 by the protruding ridges 11 spaced in the circumferential direction. Can be greatly reduced, the ease of insertion can be improved, and there is an advantage that assembly is easy.

In addition, since the ridges 11 are provided at equal intervals in the circumferential direction, the effect of preventing the variation in the path length of the wire 4 can be generated even when the sheath 1 for the flexible manipulator is bent in any direction.
Further, since the ridges 11 are provided over the entire length of the multi-lumen tube 9 in the longitudinal direction, the effect of preventing the fluctuation of the path length of the wire 4 can be made uniform regardless of the position in the longitudinal direction of the sheath 1 for the flexible manipulator Can be generated.

In addition, in this embodiment, although the thing of the cross-sectional rectangle was illustrated as the protruding item | line 11, the dimension may be arbitrary. For example, as FIG. 4 shows, the width dimension of each convex strip 11 may be larger than FIG.
Moreover, the cross-sectional shape of the ridge 11 is not limited to a rectangle, and as shown in FIG. 5, a shape having a convex curved surface at the tip, for example, a semicircular cross-section may be adopted. Moreover, you may employ | adopt the thing whose cross section tapering toward a front-end | tip is a triangle. By doing in this way, a contact area with the inner surface of the coil tube 10 can be reduced, and the ease of insertion in the coil tube 10 can be improved.

Further, as shown in FIG. 6, the multi-lumen tube 9 extends from the outer peripheral surface of the multi-lumen tube 9 while being inclined with respect to the radial direction, and falls down along the outer peripheral surface of the multi-lumen tube 9 when inserted into the coil tube 10. The ridge 11 having a cross-sectional shape that is elastically deformed may be employed. In addition, although the thing falling down in the same direction was illustrated in FIG. 6, you may decide to have a shape which falls in the reverse direction alternately.

Moreover, in this embodiment, although illustrated about the case where the protruding item | line 11 was provided continuously over the full length of the longitudinal direction of the multi-lumen tube 9, it is not limited to this, It interrupts in a longitudinal direction It may be provided. Further, the ridges 11 may be formed in a spiral shape that rotates in the circumferential direction along the longitudinal direction of the multi-lumen tube 9. Thereby, the insertion ease at the time of inserting the multi-lumen tube 9 in the coil tube 10 can be improved.

In this case, the pitch of the spiral ridges 11 is preferably different from the pitch of the coil tube 10. Thereby, it can prevent that the protruding item | line 11 and the coil tube 10 mesh in the case of insertion, and can improve insertion ease. It is preferable that the pitch of the ridges 11 is sufficiently larger than the pitch of the coil tube 10. Further, the twist direction of the ridges 11 may be opposite to the twist direction of the coil tube 10.

In the present embodiment, the multi-lumen tube 9 having four lumens 8 is illustrated as the inner tube, but instead, a single lumen tube having a single lumen 8 or an arbitrary number of two or more A multi-lumen tube having a plurality of lumens may be employed.

In the present embodiment, the multi-lumen tube 9 in which the lumen 8 extends straight along the longitudinal direction is illustrated, but instead, a twisted multi-lumen in which the lumen 8 is twisted in one direction around the central axis. A tube may be employed. In this case, the ridges 11 may be formed straight along the longitudinal direction of the multi-lumen tube 9, but when manufactured by twisting after extrusion, the pitch is the same as the twist pitch of the lumen 8. It may be twisted.

In this case, it is preferable that each protrusion 11 is formed on the side opposite to the lumen 8 across the center line of the multi-lumen tube 9 as shown in FIG. It is possible to prevent the multi-lumen tube 9 from being deformed by receiving a force acting on the lumen 8 by the tension of the wire 4 so that the lumen 8 is straightened. As shown in FIG. 8, the number of ridges 11 may not be the same as the number of lumens 8.

Further, as shown in FIG. 9, a hollow portion 12 may be provided at the base of each ridge 11, and the ridge 11 may be easily displaced in the radial direction. Thereby, the ease of insertion of the multi-lumen tube 9 into the coil tube 10 can be improved. The cavity 12 may be provided continuously over the entire length in the longitudinal direction, or may be provided intermittently.

Moreover, in this embodiment, although the case where the protrusion provided in the outer peripheral surface of the multi-lumen tube 9 was the protruding item | line 11 provided along the longitudinal direction was described, it replaced with this and it spaced apart in the circumferential direction and the longitudinal direction A plurality of protrusions may be provided with a gap.
Also, as the outer tube, any other tube may be used instead of the coil tube 10.

1 Sheath for flexible manipulator 4 Wire 8 Lumen 9 Multi-lumen tube (inner tube)
10 Coil tube (outer tube)
11 Projections (projections)
12 Cavity

Claims

A flexible inner tube with a lumen that penetrates the wire along the longitudinal direction;
An outer tube disposed so as to cover the outer peripheral surface of the inner tube, and having a higher compression rigidity and flexibility than the inner tube;
A sheath for a flexible manipulator, wherein a plurality of protrusions whose outer ends in the radial direction are brought into close contact with the inner surface of the outer tube are provided on the outer peripheral surface of the inner tube at intervals in the circumferential direction.
The sheath for a flexible manipulator according to claim 1, wherein the protrusion is formed of a ridge extending in the longitudinal direction of the inner tube.
The sheath for a flexible manipulator according to claim 2, wherein the protrusion extends continuously over the entire length of the inner tube.
The sheath for a flexible manipulator according to claim 2, wherein the protrusion extends intermittently over the entire length of the inner tube.
The sheath for a flexible manipulator according to any one of claims 1 to 4, wherein a tip of the protrusion has a cross-sectional shape formed of a convex curved surface.
The sheath for a flexible manipulator according to any one of claims 1 to 4, wherein the protrusion has a cross-sectional shape extending from the outer peripheral surface of the inner tube while being inclined with respect to the radial direction.
The sheath for a flexible manipulator according to any one of claims 1 to 6, wherein the sheath has a hollow portion radially inward of the protrusion.
The sheath for a flexible manipulator according to any one of claims 1 to 7, wherein the protrusion is provided in a spiral shape that twists around a longitudinal axis.
The inner tube comprises a plurality of lumens;
Each of the lumens is formed in a spiral shape that twists about the longitudinal axis and does not cross each other,
The sheath for a flexible manipulator according to claim 8, wherein the protrusion is disposed on the opposite side of each lumen with a center line of the inner tube interposed therebetween.
The outer tube is a coil tube;
The sheath for a flexible manipulator according to claim 8 or 9, wherein a pitch of the spiral shape of the protrusion is larger than a pitch of the coil tube.