JP2012110525A - Endoscope mounting fixture - Google Patents

Abstract

The flexibility of an insertion portion of an endoscope is maintained, and the bending operation of the bending portion is smoothly performed.
One rotating body is driven by two first and second transmission portions 11a and 11b divided in the front-rear direction. The rotating body 34 rotates following the rotation of the worm wheel 42 provided in each of the first and second transmission portions 11a and 11b. The rotating body 34 is divided into an outer portion and an inner portion with the worm wheel 42 interposed therebetween, and is configured such that the looseness rate of the outer portion is smaller than the looseness rate of the inner portion.
[Selection] Figure 5

Description

  The present invention relates to an endoscope mounting tool that is used by being mounted on an insertion portion of an endoscope having a curved portion.

  The technique of inserting an endoscope into a body duct, such as the large intestine, is difficult because the large intestine has a tortuous structure in the body and there are parts that are not fixed to the body cavity, such as the sigmoid colon and the transverse colon . For this reason, much experience is required to learn the technique for inserting an endoscope into the large intestine, and if the insertion technique is immature, the patient will be greatly distressed.

  For this reason, Patent Document 1 proposes a self-propelled wearing tool that propels the endoscope in the insertion direction in the intestine so that the insertion procedure can be easily performed. According to this, the endoscope can be guided to the deep part of the intestinal tract by circulatingly rolling the toroidal rotating body and applying a driving force in the insertion direction to the endoscope.

Special table 2009-513250 gazette

  However, the mounting tool described in Patent Document 1 does not have a configuration in which the holding portion (support structure and housing structure) of the rotating body is curved. Moreover, the holding part of the rotating body is formed long in parallel with the long axis direction of the insertion part. For this reason, there is a possibility that the bending operation of the bending portion is hindered by the mounting of the mounting tool, the flexibility of the insertion portion is partially lost, and the insertion procedure may be difficult.

  In addition, the wearing tool described in Patent Document 1 does not consider the loosening of the rotating body. For this reason, even if the mounting portion described in Patent Document 1 has a structure in which the holding portion is curved, there is a problem that the bending operation of the bending portion is hindered by the rotating body. In other words, the rotating body is flexible, but if the amount of expansion and contraction of the rotating body is large, sufficient propulsive force cannot be applied to the endoscope, so the amount of expansion and contraction of the rotating body is set small (the rotating body hardly expands or contracts). ). For this reason, if there is no moderate slack in the rotating body, the length of the rotating body outside the center axis of bending may not be sufficient and the bending operation may be hindered.

  The present invention has been made in view of the above-described problems, and an object thereof is to maintain the flexibility of the insertion portion of the endoscope and smoothly perform the bending operation of the bending portion.

In order to achieve the above object, an endoscope mounting tool according to the present invention is attached to an insertion portion of an endoscope and is powered by an external drive source to advance and retract the endoscope in an inspection hole. A propulsion-type endoscope mounting tool, which is arranged side by side in the front and rear in the axial direction of the bending portion and a hollow toroidal rotating body that circulates and rolls along the axial direction of the bending portion, First and second transmission mechanisms for transmitting power to the rotating body, the first transmission mechanism is disposed on the front end side in the axial direction, and is connected to the second transmission mechanism via an elastic body, The second transmission mechanism is disposed on the rear end side in the axial direction, receives power from the drive source, transmits the supplied power to the first transmission mechanism via the elastic body, and The first and second transmission mechanisms include a cylindrical support member through which the bending portion is inserted, A cylindrical worm gear that is formed in a cylindrical shape that covers the support member, that is powered by the drive source and rotates in contact with the peripheral surface of the support member about the axis of the curved portion, and the worm gear is covered. A first cylinder and a through-hole penetrating the peripheral surface of the first cylinder are engaged with the worm gear, and rotate around an axis orthogonal to the axis of the bending portion as the worm gear rotates. A worm wheel and a second cylinder disposed inside the rotator so as to cover the first cylinder and sandwiching the rotator between the worm wheel and the first transmission unit; Rotate the length in the rotational direction of the rotating body that exists between the worm wheel and the outer side of the second cylinder of the first and second transmission parts until it reaches the worm wheel of the second transmission part. Outside the body With the length of the portion, the worm of the second transmission part rotates from the worm wheel of the first transmission part to the outside of the second cylinder of the first and second transmission parts in a state where the bending part is not curved. The distance between the worm wheels until reaching the wheel is the outer circumference distance between the worm wheels, and the value obtained by subtracting the outer circumference distance between the worm wheels from the length of the outer portion of the rotating body is the loosening amount E _1, the loosening amount E ₁ of the rotating member outer portion, the value obtained by dividing the outer loop distance between the worm wheel in a state in which the bending portion is not curved, and slack rate r ₁ of the rotating member outer portion Further, the rotation that exists between the worm wheel of the first transmission part and the worm wheel of the second transmission part through the inside of the second cylinder of the first and second transmission parts. The length in the rotational direction of the body is the length of the inner portion of the rotating body, and the second transmitting portion passes through the inside of the second cylinder of the first and second transmitting portions from the worm wheel of the first transmitting portion. The distance between the worm wheels until reaching the worm wheel is the inward distance between the worm wheels, and the value obtained by subtracting the inward distance between the worm wheels from the length of the inner part of the rotator the loosening amount E ₂ portions, the loosening amount E ₂ of the rotary body portion, the value obtained by dividing the inner loop distance between the worm wheel in a state in which the bending portion is not curved, slack rate of rotation body portion r _The rotating body is configured to satisfy r ₁ <r ₂ when ₂ .

The distance from the front end of the second cylinder of the first transmission part to the rear end of the second cylinder of the second transmission part is L ₁ , the inward distance between the worm wheels is L ₂ , and the bending part is curved. The radius of the arc drawn by the center line of the curved portion is R, the diameter of the second cylindrical body is D, and the inner portion of the rotating body is generated by the rotational phase difference of the worm wheel of the first and second transmitting portions. The rotating body may be configured to satisfy r ₁ ≧ (D / 2R) + (α / (2L ₁ −L ₂ )), where α is the amount of change in length.

Further, the distance from the front end of the second cylinder of the first transmission part to the rear end of the second cylinder of the second transmission part is L ₁ , the inward distance between the worm wheels is L ₂ , and the bending part is When bent, the radius of the arc drawn by the center line of the curved portion is R, the diameter of the second cylindrical body is D, and the inside of the rotating body is generated by the rotational phase difference of the worm wheel of the first and second transmitting portions. The rotating body may be configured to satisfy r ₂ ≧ (D / 2R) + (α / L ₂ ), where α is the amount of change in the length of the portion.

  Furthermore, the elastic body may be constituted by three-layer coil springs composed of three coil springs having different winding diameters and combined in three layers so that the winding direction is reversed in order.

  Further, only one of the first and second transmission units may be fixed to the bending unit.

  Furthermore, you may fix both the said 1st, 2nd transmission part to the said bending part.

  Moreover, you may attach the cover which has the flexibility while covering the said elastic body.

  Further, the elastic body connects the rear end portion of the worm gear of the first transmission portion and the front end portion of the worm gear of the second transmission portion, and the worm gear of the second transmission portion is powered from the drive source. You may rotate with.

  Moreover, while providing a pair of said driven roller, you may arrange | position the said worm wheel between a pair of said driven rollers.

  Further, the rotating body may be formed of an impermeable material and a liquid may be sealed inside the rotating body.

  The rotating body may be formed of an impermeable material, and a gel may be enclosed inside the rotating body.

  Furthermore, the rotating body may be formed of a biocompatible plastic.

  The first and second transmission mechanisms may be remotely operated.

  In the endoscope mounting tool of the present invention, the two transmission mechanisms are connected by an elastic body so that the holding portion of the rotating body has sufficient flexibility and the rotating body is configured in consideration of the amount of slack. Therefore, the flexibility of the insertion portion of the endoscope can be maintained, and the bending operation of the bending portion can be performed smoothly.

It is a schematic diagram of an endoscope system. It is a perspective view which shows the state which mounted | wore the electronic endoscope with the self-propulsion apparatus. It is a disassembled perspective view of a self-propulsion device. It is sectional drawing of a self-propulsion apparatus. It is explanatory drawing which shows the mode of a rotary body when a self-propulsion apparatus is not curving. It is explanatory drawing which shows the mode of a rotary body when a self-propulsion apparatus curves. It is explanatory drawing which shows a mode that the cylinder of length L diameter D curved by angle (theta) so that a center might follow the circular arc of radius R. FIG.

  In FIG. 1, the endoscope system 2 includes an electronic endoscope 10 and a self-propelling device 11. The electronic endoscope 10 includes a hand operation unit 12 and an insertion unit 13 connected to the hand operation unit 12 and inserted into a body duct (for example, large intestine). A universal cord 14 is connected to the hand operating unit 12, and a connector (not shown) that is detachably connected to a light source device and a processor device (both not shown) is provided at the tip of the universal cord 14. Yes.

  The hand operating section 12 is provided with an angle knob 15, an air / water feed button 16 for ejecting air and water from the distal end of the insertion section 13, a suction button 17, and the like. A forceps port 18 through which a treatment tool such as an electric knife is inserted is provided on the insertion unit 13 side of the hand operation unit 12.

  The insertion portion 13 includes a flexible soft portion 19, a bendable bending portion 20, and a distal end rigid portion 21 in order from the hand operation portion 12 side. The flexible part 19 has a length of several meters in order to allow the distal rigid part 21 to reach a target position in the body duct. The bending portion 20 bends vertically and horizontally in conjunction with the operation of the angle knob 15 of the hand operation portion 12. Thereby, the front-end | tip rigid part 21 can be orient | assigned to the desired direction in a body.

  The distal end rigid portion 21 has an observation window 30 (see FIG. 2) for capturing an image of the site to be observed in the body, an objective optical system, and a solid-state imaging device such as a CCD or a CMOS image sensor that images the image of the site to be observed. Is provided. The solid-state imaging device is connected to the processor device through a signal cable inserted through the insertion unit 13, the hand operation unit 12, and the universal cord 14. The image of the site to be observed is formed on the light receiving surface of the solid-state imaging device and converted into an imaging signal. The processor device performs various types of image processing on the imaging signal from the solid-state imaging device received via the signal cable to convert it into a video signal, and displays this as an observation image on a cable-connected monitor (not shown).

  In FIG. 2, the distal end rigid portion 21 is incorporated in the light source device according to the operation of the illumination window 31 for irradiating the observation site with the illumination light from the irradiation light source of the light source device and the air / water supply button 16. An air supply / water supply nozzle 32 for injecting air and water supplied from the air supply / water supply device toward the observation window, and a forceps outlet 33 for exposing the distal end of the treatment instrument inserted through the forceps port 18 are provided. It has been.

  Returning to FIG. 1, the self-propulsion device 11 is a device that is attached to the electronic endoscope 10 and assists the advancement and retraction of the insertion portion 13 of the electronic endoscope 10 in the body duct. The self-propulsion device 11 is driven by a power source 22. The power source 22 is connected to a torque wire 49 (see FIG. 3) that transmits a driving force to the self-propulsion device 11. The torque wire 49 is inserted into the protective sheath 23 over the entire length. By driving the power source 22, the torque wire 49 rotates within the protective sheath 23.

  Connected to the rear end of the self-propulsion device 11 is an overtube 24 that is extendable in the direction of the axis of the insertion portion 13 (insertion axis A). The overtube 24 is provided in order to make the insertion portion 13 and the torque wire 49 (protective sheath 23) integral. The insert portion 13 and the protective sheath 23 are both inserted into the overtube 24.

  The power source 22 is controlled by a control device (not shown), and an operation unit (not shown) is attached to the control device. The operation unit includes a button for inputting a forward / reverse / stop instruction for the self-propulsion device 11, a speed change button for changing the moving speed of the self-propulsion device 11, and the like. Note that a program corresponding to an observation target or the like may be preliminarily set, and the power source 22 may be driven according to the program and the self-propulsion device 11 may be automatically operated without manual operation of the operation unit.

  In FIG. 2, the self-propelling device 11 includes a rotating body 34. The rotating body 34 is formed in a hollow toroidal shape (a shape like a floating ring that connects both ends of the tube to form an annular shape), and a liquid is sealed inside (see FIG. 4). The rotator 34 is a biocompatible plastic that is impervious to prevent external foreign matter from entering the inside or leaking the liquid enclosed therein, and flexible so that it can be smoothly circulated. Is formed. Polyvinyl chloride is used as the biocompatible plastic. In place of polyvinyl chloride, polyamide resin, fluororesin, polyurethane resin, or the like can be used. Moreover, it can replace with a liquid and can also enclose it combining a gel, gas, or these.

  The self-propulsion device 11 is fixed so as not to be displaced with respect to the insertion portion 13 by fitting a support member 45 (see FIGS. 3 and 4) described later to the insertion portion 13. The self-propulsion device 11 circulates and rolls the rotating body 34 along the axial direction of the insertion axis A while being fixed to the insertion portion 13. When the outer surface 34 a comes into contact with the inner wall of the body duct when the rotating body 34 is circulated and rolled, the insertion portion 13 is pulled by the rotating body 24 and propelled along the insertion axis A together with the rotating body 24. When the insertion portion 13 is propelled in the insertion direction, the rotating body 34 is circulated and rolled so that the outer surface 34 a exposed to the outside moves in a direction opposite to the insertion direction of the insertion portion 13. Conversely, when the insertion portion 13 is propelled in the direction opposite to the insertion direction, the rotating body 34 is circulated and rolled so that the outer surface 34a exposed to the outside moves in the same direction as the insertion direction of the insertion portion 13. Is done.

  3 and 4, the self-propulsion device 11 includes a first transmission unit 11 a and a second transmission unit 11 b that transmit the power supplied from the power source 22 to the rotating body 34. The first transmission part 11 a and the second transmission part 11 b are attached to the bending part 20 of the insertion part 13 of the electronic endoscope 10. And the 1st transmission part 11a is arrange | positioned at the front side, and the 2nd transmission part 11b is arrange | positioned at the back side.

  The 1st transmission part 11a and the 2nd transmission part 11b are provided with the 1st cylinder 40 and the 2nd cylinder 41, respectively. Both the 1st cylinder 40 and the 2nd cylinder 41 are formed in the cylindrical shape, and the length regarding the axial direction of the insertion axis A is the same. The first cylinder 40 has a smaller diameter than the second cylinder 41, and the first cylinder 40 is accommodated in the second cylinder 41 and covered with the second cylinder 41. In addition, illustration of the rotary body 34 is abbreviate | omitted in FIG.

  A worm wheel 42 that rotates about an axis orthogonal to the insertion axis A is attached to the through hole 40 a formed in the peripheral surface of the first cylinder 40. The worm wheel 42 is disposed at the center of the first cylinder 40 with respect to the axial direction of the insertion axis A, and three worm wheels 42 are attached at 120 ° intervals in the circumferential direction of the first cylinder 40.

  On the other hand, a pair of driven rollers 43 that rotate about an axis parallel to the central axis of the worm wheel 42 are provided in the through hole 41 a formed in the peripheral surface of the second cylindrical body 41 in the circumferential direction of the second cylindrical body 41. Are attached at intervals of 120 °. When the first cylinder 40 is stored in the second cylinder 41, the relative positioning of the second cylinder 41 and the first cylinder 40 is such that each worm wheel 42 enters between each pair of driven rollers 43. Has been made. The rotating body 34 is wound around the entire circumference of the second cylinder 41 through holes at both ends thereof. The rotating body 34 is held between the worm wheel 42 and the driven roller 43. Each driven roller 43 abuts on the inner surface 34 b of the rotating body 34 and rotates following the circular rolling of the rotating body 34.

  A cylindrical worm gear 44 is accommodated in the first cylinder 40. The worm gear 44 is fitted into a cylindrical support member 45. The insertion portion 13 of the electronic endoscope 10 is fitted into the support member 45 and the support member 45 is fixed to the insertion portion 13. In a state where the support member 45 is fitted into the insertion portion, the distal end hard portion 21 protrudes from the support member 45 of the first transmission portion 11a. The worm gear 44 has gear teeth formed on the outer peripheral surface thereof, and rotates around the insertion axis A while being in sliding contact with the outer peripheral surface of the support member 45. A worm wheel 42 is engaged with the worm gear 44, and the worm wheel 42 rotates in conjunction with the rotation of the worm gear 44.

  The second transmission part 11 b includes a rear lid 46. The rear lid 46 is formed in an annular shape, and is fitted and fixed to the outer periphery of the rear end portion of the support member 45 of the second transmission portion 11b. Further, the rear end portion of the first cylinder 40 of the second transmission portion 11 b is fitted and fixed to the outer periphery of the rear lid 46. Thus, in the 2nd transmission part 11b, the 1st cylinder 40 and the support member 45 are integrated via the back cover 46 (the 1st cylinder 40 is fixed with respect to the support member 45).

  A driven gear 47 in which a plurality of gear teeth are arranged around the axis of the insertion shaft A is formed at the rear end portion of the worm gear 44 of the second transmission portion 11b. A pinion gear 48 is attached to the rear lid 46. The central axis of the pinion gear 48 is parallel to the insertion axis A. A pinion gear 48 meshes with the driven gear 47. The pinion gear 48 is connected to the torque wire 49. As a result, the pinion gear 48 rotates in conjunction with the torque wire 49. The torque wire 49 is composed of three coil springs having different winding diameters, and is combined in three layers so that the winding direction is reversed in order. Therefore, the torque wire 49 can transmit power even if it rotates in either direction of both rotation directions. When the pinion gear 48 rotates, the driven gear 47 rotates in conjunction with this.

  The first transmission unit 11 a includes a front lid 50. The front lid 50 is formed in an annular shape, and is fitted and fixed to the outer periphery of the front end portion of the support member 45 of the first transmission portion 11a. Further, the front end portion of the first cylinder 40 of the first transmission portion 11a is fitted and fixed to the outer periphery of the front lid 50. Thus, in the 1st transmission part 11a, the 1st cylinder 40 and the support member 45 are integrated via the back cover 46 (the 1st cylinder 40 is fixed with respect to the support member 45).

  The rear end portion of the worm gear 44 of the first transmission portion 11a is provided with a step that is lowered by one step, and the front end portion of the worm gear 44 of the second transmission portion 11b is provided with a step that is lowered by one step. A connecting sleeve 51 is fitted into the step portion of each worm gear 44 from one side. One end of a coupling three-layer coil spring 52 is fitted into the other side of each coupling sleeve 51. The connecting sleeve 51 and the connecting three-layer coil spring 52 rotate integrally with the worm gear 44. Thereby, the rotational force of the worm gear 44 of the 2nd transmission part 11b is transmitted to the worm gear 44 of the 1st transmission part 11a.

  The connecting three-layer coil spring 52 includes an outermost first coil spring 52a, a second coil spring 52b having an outer diameter substantially equal to the inner diameter of the first coil spring 52a, and an outer diameter substantially equal to the inner diameter of the second coil spring 52b. And three coil springs 52c. The first to third coil springs 52a to 52c are combined in three layers so that the winding directions are reversed in order. Specifically, the first coil spring 52a and the third coil spring 52c are wound counterclockwise, and the second coil spring 52b is wound clockwise.

  For this reason, when the connecting three-layer coil spring 52 rotates counterclockwise as the connecting sleeve 51 rotates, the first coil spring 52a and the third coil spring 52b are tightened inward and the second coil spring 52b is loosened outward. . Thereby, the first coil spring 52a and the second coil spring 52b are tightened to transmit the rotational force with high efficiency. When the connecting three-layer coil spring 52 rotates clockwise as the connecting sleeve 51 rotates, the first coil spring 52a and the third coil spring 52b are loosened outward and the second coil spring 52b is tightened inward. As a result, the second coil spring 52b and the third coil spring 52c are tightened to transmit the rotational force with high efficiency. The torque wire 49 may also be constituted by a three-layer coil spring, similar to the three-layer coil spring 52 for connection.

  One end of a tubular cover 53 having flexibility in the axial direction of the insertion portion 13 is attached to each connection sleeve 51. The connecting three-layer coil spring 52 is covered with a cover 53. This prevents body fluid and the like from adhering to the coil spring 52. In addition, illustration of the cover 53 is abbreviate | omitted in FIG.

  The self-propulsion device 11 has a distance between the first and second transmission portions 11a and 11b so that the first, second, and third coil springs 52a, 52b, and 52c of the connecting three-layer coil spring 52 are not in close contact with each other. Is adjusted and fixed to the insertion portion 13. And when the insertion part 13 curves, the self-propulsion apparatus 11 will bend following the curve of the insertion part 13, when the inner side of the connection three-layer coil spring 52 contracts and the outer side extends.

  As described above, in the self-propulsion device 11 of the present invention, the first and second transmission portions 11 a and 11 b are connected by the connecting three-layer coil spring 52. For this reason, the holding mechanism of the rotating body 34 has sufficient flexibility. However, since the rotating body 34 hardly expands or contracts, if the loosening of the rotating body 34 is not appropriate, the smooth bending of the holding mechanism of the rotating body 34 is hindered.

  The rotating body 34 is configured to move following the rotation of the worm wheel 42 provided in each of the first and second transmission portions 11a and 11b (the worm wheel 42 does not idle). For this reason, when the slack of the rotating body 34 is determined, it is necessary to determine the slack of each of the inner part and the outer part of the rotating body 34 with the worm wheel 42 interposed therebetween.

  As shown in FIGS. 5 and 6, the outer portion of the rotating body 34 refers to the second portion of the first transmitting portion 11 a from the worm wheel 42 of the first transmitting portion 11 a toward the distal end side in the insertion direction. A portion from the outer side of the cylindrical body 41 and the second transmission portion 11b of the second transmission portion 11b to the worm wheel 42 of the second transmission portion 11b from the rear end side in the insertion direction (broken line in FIGS. 5 and 6) (The part surrounded by). In addition, the inner part of the rotating body 34 refers to the second cylinder 41 and the second transmission of the first transmission part 11a from the worm wheel 42 of the first transmission part 11a toward the rear end side in the insertion direction. A part from the inside of the second cylinder 41 of the part 11b to the worm wheel 42 of the second transmission part 11b from the distal end side in the insertion direction (part surrounded by a two-dot chain line in FIGS. 5 and 6) It is.

In determining the slack between the inner part and the outer part of the rotating body 34, the average value of the outer diameter and the inner diameter of the second cylinder 41 was D. Further, the insertion direction leading end of the second cylindrical body 41 of the first transmission unit 11a, a length of up to the insertion direction rear end of the second cylindrical body 41 of the second transmission unit 11b and L _1, the first transmission unit 11a the distance between the worm wheel 42 and the worm wheel 42 of the second transmission section 11b (the inner loop distance between the worm wheel) was L _2. The rotating body 34 is curved along an arc having a radius R at the center.

Further, the rotating body 34 passes through a position that is separated from the center of the self-propelling device 11 by D / 2 in both the outer portion and the inner portion. That is, the rotator 34 has no thickness in the direction perpendicular to the insertion direction (see FIG. 7), and the minimum necessary length for one week of the rotator 34 when the self-propelling device 11 is not curved. Is 2L ₁ , the minimum required length (outer circumference distance between worm wheels) as the outer part of the rotating body 34 is (2L ₁ -L ₂ ), and the minimum required length (worm wheel) as the inner part of the rotating body 34 Uchimawari distance between) of the _{L 2} (see FIG. 5). The center length of the self-propelling device 11 does not change regardless of whether the self-propelling device 11 is curved.

Here, as shown in FIG. 7 (A), a cylinder 60 having a length L and a diameter D, which is regarded as a rotating body 34, is aligned with an arc having a radius R as shown in FIG. 7 (B). Is bent at an angle θ, the center length of the cylinder 60 after bending is Rθ, and the center length of the cylinder 60 is constant at L before and after the curve,
L = Rθ
Therefore, when θ is obtained from here,
θ = L / R (Formula 1)
It becomes.
The length L _a of the outer portion of the cylinder 60 after curvature (center to D / 2 only bent outwardly to distant parts of the cylinder 60),
L _a = (R + (D / 2)) θ (Formula 2)
It is.
If θ is eliminated from Equation 1 and Equation 2,
L _a = ((R + (D / 2)) L / R)
= L + (DL / 2R)
It becomes.
Since the length of the outer portion of the cylinder 60 before bending is L, the amount of change E of the length of the outer portion of the cylinder 60 due to bending is
E = L _a -L
= L + (DL / 2R) -L
= DL / 2R
It becomes.
In this way, when the cylinder 60 having the center length L and the diameter D is curved at the radius R, at the outer portion of the cylinder 60, that is, at a point away from the arc of the radius R by “D / 2” outward in the bending direction, “DL / 2R "is longer than the original length L (" D / 2R "times the original length is longer than the original length).

  In consideration of the example of FIG. 7 described above and the fact that the rotating body 34 hardly expands or contracts in the self-propulsion device 11, in the present invention, when the self-propulsion device 11 is curved so that the center is along an arc of radius R, The length of the rotator 34 that passes outside by D / 2 from the center of the device 11 is set to “D / in advance with respect to the original length (minimum necessary length when the self-propelling device 11 is not curved). It is necessary to make it 2 times longer (make the rotating body 34 slack).

In the state where the self-propelling device 11 is not curved, the minimum necessary length as the outer portion of the rotating body 34 is
2L ₁ -L ₂
Therefore (see [0050]), when the self-propelling device 11 is bent so that the center is along the arc of the radius R, the amount of slack E ₁ required for the inner portion of the rotating body 34 is obtained.
E ₁ ≧ (2L ₁ −L ₂ ) D / 2R
It is.

Similarly, in a state where the self-propelling device 11 is not curved, the minimum necessary length as the inner portion of the rotating body 34 is
L ₂
Therefore, when the self-propelling device 11 is bent so that the center is along an arc of radius R, the amount of slack E ₂ required for the inner part of the rotating body 34 is obtained.
E ₂ ≧ L ₂ D / 2R
It is.

  However, the amount of slack calculated as described above is the minimum amount of slack necessary for bending, and the rotational phase shift of the worm wheel 42 of the first and second transmission portions 11a and 11b is taken into consideration. Absent. That is, in the self-propulsion device 11, the driving force supplied to the second transmission portion 11b is transmitted to the first transmission portion 11a by the connecting three-layer coil spring 52, so that the driving force can be transmitted efficiently, but the first transmission portion The driving force is transmitted to the worm wheel 42 of 11a slightly later than the worm wheel 42 of the second transmission portion 11b. For this reason, a slight rotational phase shift occurs between the worm wheels 42 of the first and second transmission portions 11a and 11b. As a result, when the self-propelling device 11 is moved forward or backward, the amount of looseness between the outer portion and the inner portion of the rotating body 34 is temporarily changed.

By considering such a shift in the rotational phase of the worm wheel 42, a smoother curve is possible. For this reason, a temporary change amount of the slack amount due to the rotational phase shift of the worm wheel 42 (a change amount of the length of the inner portion of the rotating body) is α, which is necessary for the outer portion of the rotating body 34 calculated previously. When the slack amount E ₁ and the slack amount E ₂ required for the inner portion of the rotating body 34 are added, the slack amounts E ₁ and E ₂ are expressed by the following equations.
E ₁ ≧ ((2L ₁ −L ₂ ) D / 2R) + α
E ₂ ≧ (L ₂ D / 2R) + α

Subsequently, based on the amount of slackness E ₁ of the outer portion of the rotating body 34 calculated as described above, the self-propulsion device 11 is not curved with respect to the slackness ratio r ₁ (E ₁₎ of the outer portion of the rotating body 34. , The minimum required length 2L ₁ -L ₂ as the outer portion of the rotating body 34)
r ₁ ≧ E ₁ / (2L ₁ -L ₂ )
≧ (D / 2R) + (α / (2L ₁ −L ₂ ))
It becomes.

Similarly, the slackness ratio r ₂ of the inner part of the rotating body 34 (value obtained by dividing E ₂ by the minimum required length L ₂ as the inner part of the rotating body 34 when the self-propelling device 11 is not curved). Ask for
r ₂ ≧ E ₂ / L ₂
≧ (D / 2R) + (α / L ₂ )

Here, since L ₁ > L ₂ ,
r ₁ <r ₂
It is.

In the self-propulsion device 11, the rotating body 34 is configured so as to satisfy r ₁ <r ₂ in consideration of the slackness of the rotating body 34 as described above. As a result, the self-propelling device 11 smoothly curves following the bending of the bending portion 20.

In addition to satisfying r ₁ <r ₂ , r ₁ ≧ (D / 2R) + (α / (2L ₁ −L ₂ )) and r ₂ ≧ (D / 2R) + (α / L ₂ ) May be configured to satisfy one or both of the above. In this way, a smoother curve is possible.

Further, specific values of L ₁ , L ₂ , D, α, and R are preferably in the following ranges.
20 mm ≦ L ₁ ≦ 60 mm
10 mm ≦ L ₂ ≦ 50 mm
15mm ≦ D ≦ 30mm
0.1mm ≦ α ≦ 2mm
15mm ≦ R

  The operation of the endoscope system 2 configured as described above will be described. First, the overtube 24 is attached to the insertion portion 13 of the electronic endoscope 10, and the insertion portion 13 is inserted into the support member 45 to attach the self-propulsion device 11 to the insertion portion 13.

  After the overtube 24 and the self-propelling device 11 are attached, the processor device, the light source device, the control device, and the like are turned on, and then patient information and the like are input. Thereafter, the insertion part 13 of the electronic endoscope 10 is inserted into the body duct of the patient.

  After the distal rigid portion 21 is advanced to a predetermined position in the body duct, for example, just before the sigmoid colon, the power source 22 of the self-propelling device 11 is turned on by operating the operation unit. When a forward instruction is input by operating the button of the operation unit after the power is turned on, the torque wire 49 to which the driving force is given by the power source 22 rotates in a predetermined direction. In the second transmission portion 11 b, the pinion gear 48 rotates in conjunction with the rotation of the torque wire 49, and the worm gear 44 rotates in conjunction with the rotation of the pinion gear 48. When the worm gear 44 is rotated by the second transmission portion 11b, the connecting three-layer coil spring 52 is rotated together, and the worm gear 44 of the first transmission portion 11a is also rotated. In the present embodiment, since the rotational force of the worm gear 44 of the second transmission portion 11b is transmitted by the connecting three-layer coil spring 52, the rotational force can be efficiently transmitted to the worm gear 44 of the first transmission portion 11a.

  When the worm gear 44 rotates in both the first transmission unit 11a and the second transmission unit 11b, the worm wheel 42 rotates in conjunction with the rotation. When the worm wheel 42 rotates, the rotating body 34 circulates and rolls. When the outer surface 34 a of the rotating body 34 is in contact with the inner wall of the body duct, the self-propulsion device 11 advances in the insertion direction of the insertion portion 13. Along with this, the distal rigid portion 21 advances along the inner wall of the body duct.

  When a speed change instruction is input by operating the button of the operation unit, the rotational speed of the torque wire 49 is changed by the power source 22, and the forward speed of the self-propulsion device 11 is changed. Further, when a reverse instruction is input by operating the button of the operation unit, the torque wire 49 is reversely rotated by the power source 22 and the self-propulsion device 11 is moved backward. Along with this, the distal rigid portion 21 moves backward along the inner wall of the body duct. When a stop instruction is input by operating the button of the operation unit, the driving of the power source 22 stops and the self-propulsion device 11 also stops. By appropriately performing the above operations, the distal rigid portion 21 can be propelled to a desired position in the body duct.

  The operator appropriately operates the angle knob 15 to bend the bending portion 20 of the electronic endoscope 10 and direct the distal rigid portion 21 in a desired direction. In the self-propulsion device 11, the first transmission part 11 a and the second transmission part 11 b are connected by a connecting three-layer coil spring 52, and therefore the connecting three-layer coil spring 52 is bent together with the bending part 20 by its flexibility. The first transmission unit 11a and the second transmission unit 11b follow the bending of the bending unit 20.

Also, the self-propelled machine 11, since the looseness rate r ₂ of the inner portion of the rotary member 34 constitute the rotating body 34 to be greater than the loosening rate r ₁ of the outer part of the rotating body 34, rotating body 34 does not hinder the bending operation of the self-propulsion device 11. Thereby, the self-propelling device 11 can bend smoothly following the bending operation of the bending portion 20.

In the present invention, since the rotating body may be configured to satisfy r ₁ <r ₂ , the detailed configuration can be appropriately changed without being limited to the above embodiment. For example, although the above embodiment has been described with an example in which the transmission unit is connected using a three-layer coil spring, the present invention is not limited to this. As long as it is a member that transmits the power applied to the transmission unit to the transmission unit at the connection destination and has flexibility in the axial direction of the shaft of the insertion unit, for example, the transmission unit using a single coil spring or rubber tube May be connected.

  Furthermore, in the said embodiment, the example which fixes both a 1st transmission part and a 2nd transmission part to an insertion part (The example using a common supporting member in a 1st, 2nd transmission part (refer the code | symbol 45 of FIG. 4). )), The present invention is not limited to this. Since at least one of the first and second transmission portions only needs to be fixed to the insertion portion, the inner diameter of one of the support members is made substantially equal to the outer diameter of the insertion portion so as to be fixed to the insertion portion, and the other support The inner diameter of the member may be made larger than the outer diameter of the insertion portion so as to be movable.

  In the above embodiment, the center length of the self-propelling device does not change even when the self-propelling device is curved, i.e., the three-layer coil spring is not in close contact with the line in the state where the self-propelling device is not curved. First, the example in which the outer portion of the three-layer coil spring extends and the inner portion contracts when the self-propelling device is curved has been described, but the present invention is not limited to this. For example, when the self-propelling device is not curved, the three-layer coil spring is in close contact with the line, and when the self-propelling device is curved, only the outer portion of the three-layer coil spring extends (the length of the inner portion does not change). The present invention can be applied even when the length of the center of the self-propulsion device changes when the propulsion device is curved. In this case, the same effect as that of the above embodiment can be obtained.

  In the above-described embodiment, an example in which the present invention is applied to a mounting tool for an electronic endoscope for medical diagnosis has been described. However, the present invention is not limited to this. The present invention may be applied to a fitting device for an instrument for observing ducts such as other endoscopes and ultrasonic probes for industrial use.

DESCRIPTION OF SYMBOLS 2 Endoscope system 10 Electronic endoscope 11 Self-propulsion apparatus 11a 1st transmission part 11b 2nd transmission part 13 Insertion part 19 Soft part 20 Bending part 21 Tip rigid part 34 Rotating body 35 Holding part 40 1st cylinder 41 First Two cylinders 42 Worm wheel 51 Connection sleeve 52 Three-layer coil spring for connection (elastic body)

Claims (13)

A self-propelled endoscope mounting tool that is attached to an insertion portion of an endoscope and is powered by an external drive source to advance and retract the endoscope in an inspection hole,
A hollow toroidal rotating body that circulates and rolls along the axial direction of the curved portion,
The first and second transmission mechanisms are arranged side by side in the axial direction of the bending portion, and transmit power from the drive source to the rotating body.
The first transmission mechanism is disposed on the front end side in the axial direction, and is connected to the second transmission mechanism via an elastic body,
The second transmission mechanism is disposed on the rear end side in the axial direction, receives power from the drive source, and transmits the supplied power to the first transmission mechanism via the elastic body,
The first and second transmission mechanisms are formed in a cylindrical support member through which the bending portion is inserted, and a cylindrical shape that covers the support member, and are supplied with power from the driving source to rotate the shaft of the bending portion. A cylindrical worm gear that rotates in sliding contact with the peripheral surface of the support member at the center, a first cylinder that covers the worm gear, and a worm gear that is attached to a through hole that penetrates the peripheral surface of the first cylinder. A worm wheel that meshes with and rotates around an axis orthogonal to the axis of the curved portion as the worm gear rotates, and is disposed inside the rotating body so as to cover the first cylindrical body, Each having a second cylinder sandwiching the rotating body between,
Rotation direction of the rotating body that exists between the worm wheel of the first transmission part and the outer side of the second cylinder of the first and second transmission parts until it reaches the worm wheel of the second transmission part The length of the outer part of the rotating body,
From the worm wheel of the first transmission part to the outer side of the second cylinder of the first and second transmission parts until reaching the worm wheel of the second transmission part in a state where the bending part is not curved. The distance between the worm wheels is the outer distance between the worm wheels,
A value obtained by subtracting the outer distance between the worm wheels from the length of the outer portion of the rotating body is defined as a slack amount E ₁ of the outer portion of the rotating body,
The loosening amount E ₁ of the rotating member outer portion, the value obtained by dividing the outer loop distance between the worm wheel in a state in which the bending portion is not curved, and slack rate r ₁ of the rotating member outer portion,
further,
The direction of rotation of the rotating body that exists between the worm wheel of the first transmission section and the worm wheel of the second transmission section through the inside of the second cylinder of the first and second transmission sections. Is the length of the inner part of the rotating body,
The distance between the worm wheels from the worm wheel of the first transmission part to the worm wheel of the second transmission part through the inside of the second cylinder of the first and second transmission parts is determined between the worm wheels. The inward turning distance of
From the length of the inner portion of the rotor, a value obtained by subtracting the inward turning distance between the worm wheel, the loosening amount E ₂ of the rotary body portion,
The loosening amount E ₂ of the rotary body portion, the value obtained by dividing the inner loop distance between the worm wheel in a state in which the bending portion is not curved, when the slack rate r ₂ of the rotating body portion,
An endoscope mounting tool, wherein the rotating body is configured to satisfy r ₁ <r ₂ . The distance from the front end of the second cylinder of the first transmission part to the rear end of the second cylinder of the second transmission part is L ₁ ,
An inward distance between the worm wheels is L ₂ ,
The radius of the arc drawn by the center line of the curved portion when the curved portion is curved is R,
The diameter of the second cylinder is D,
When the amount of change in the length of the inner part of the rotating body caused by the rotational phase difference of the worm wheel of the first and second transmission parts is α,
The endoscope mounting tool according to claim 1, wherein the rotating body is configured to satisfy r ₁ ≧ (D / 2R) + (α / (2L ₁ −L ₂ )). The distance from the front end of the second cylinder of the first transmission part to the rear end of the second cylinder of the second transmission part is L ₁ ,
An inward distance between the worm wheels is L ₂ ,
The radius of the arc drawn by the center line of the curved portion when the curved portion is curved is R,
The diameter of the second cylinder is D,
When the amount of change in the length of the inner part of the rotating body caused by the rotational phase difference of the worm wheel of the first and second transmission parts is α,
The endoscope mounting tool according to claim 1, wherein the rotating body is configured to satisfy r ₂ ≧ (D / 2R) + (α / L ₂ ).   The said elastic body is comprised from the three-layer coil spring combined with three layers so that it may consist of three coil springs from which a winding diameter differs, and a winding direction becomes reverse direction in order. The endoscope mounting tool described.   The endoscope mounting tool according to any one of claims 1 to 4, wherein only one of the first and second transmission portions is fixed to the bending portion.   The endoscope mounting tool according to any one of claims 1 to 4, wherein both the first and second transmission portions are fixed to the bending portion.   The endoscope mounting tool according to any one of claims 1 to 6, wherein a cover that covers the elastic body and has flexibility is attached.   The elastic body connects the rear end portion of the worm gear of the first transmission portion and the front end portion of the worm gear of the second transmission portion, and the worm gear of the second transmission portion is rotated by power from the drive source. The endoscope mounting tool according to any one of claims 1 to 7, wherein   The endoscope mounting tool according to any one of claims 1 to 8, wherein a pair of the driven rollers are provided, and the worm wheel is disposed between the pair of driven rollers.   The endoscope mounting tool according to any one of claims 1 to 9, wherein the rotating body is made of an impermeable material, and a liquid is sealed inside the rotating body.   The endoscope mounting tool according to any one of claims 1 to 9, wherein the rotating body is made of an impermeable material, and a gel is sealed inside the rotating body.   The endoscope mounting tool according to any one of 1 to 11, wherein the rotating body is made of a biocompatible plastic.   The endoscope mounting tool according to any one of claims 1 to 12, wherein the first and second transmission mechanisms are remotely operated.

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