Traction system

Abstract

This traction system comprises: a linear member that is connected to biological tissue; an electric motor that generates a traction force acting on the linear member; and a transfer device that transfers a traction device having the linear member and the electric motor between the inside and the outside of a biological tube.

Description

Traction System

[0005]

[0001] The present invention relates to a traction system. This application claims priority based on Japanese Patent Application No. 2024-203543 filed in Japan on November 21, 2024, and incorporates its content herein by reference.

[0002] Conventionally, for example, as a medical instrument used in endoscopic surgery or the like, a treatment instrument including a holding part that holds a living tissue in a body cavity and a driving part that adjusts the tension acting on the holding part from outside the body cavity is known (see, for example, Patent Document 1).

[0003] International Publication No. 2016 / 125375

[0004] For example, in the resection of living tissue by endoscopic treatment in the digestive tract or the like, such as endoscopic submucosal dissection (ESD), a method of pulling the living tissue by a gripping member such as a clip connected to an elastic member (applying so-called countertraction) is known. However, in order to appropriately attach the gripping member through an endoscope in the digestive tract or the like, there is a problem that skilled techniques and complicated procedures are required. Further, in order to perform the resection of living tissue while applying a pulling force to the gripping member inside the tube in the digestive tract or the like by a driving part outside the tube as in the treatment instrument of the above prior art, for example, a plurality of forceps ports for a plurality of treatment instruments are required in the endoscope, etc., and the configuration becomes complicated, and there is a problem that complicated procedures are required for the operation of a plurality of treatment instruments.

[0005] An aspect of the present invention aims to provide a traction system that can easily perform appropriate traction of living tissue in endoscopic treatment.

[0006] As a means for solving the above problems, an aspect of the present invention has the following configuration. (1) The traction system according to an aspect of the present invention includes a linear member connected to a living tissue, an electric motor that generates a pulling force acting on the linear member, and a transfer device that transfers a traction device having the linear member and the electric motor between inside and outside a living tube.

[0007] (2) The traction system described in (1) above includes a fixing member for fixing the electric motor inside the biotube, and the transport equipment may transport the traction device and the fixing member between inside and outside the biotube.

[0008] (3) The traction system described in (2) above includes a sensor for detecting a state quantity related to the traction force acting on the linear member, and the transport equipment may transport the traction device, the fixing member and the sensor between the inside and outside of the biological tube.

[0009] (4) In the traction system described in (3) above, the sensor may be connected to the linear member.

[0010] (5) In the traction system described in (4) above, the traction device may be provided with a rotary connector for taking the output of the sensor from the linear member.

[0011] (6) The traction system described in (3) above includes a detector that detects a state quantity related to the attitude of the linear member in order to correct the traction force detected based on the output of the sensor, and the transport equipment may transport the traction device, the fixing member, the sensor and the detector between inside and outside the biological tube.

[0012] (7) The traction system described in any one of the above paragraphs (1) to (6) may include a sealing member that liquid-tightly seals the inside of the electric motor.

[0013] (8) In the traction system described in (7) above, the transport equipment may include an endoscope and an overtube.

[0014] According to the traction system described in (1) above of the present invention, by providing a transport device that moves a linear member that applies traction force to biological tissue and an electric motor between inside and outside the biological tube, appropriate traction of biological tissue in endoscopic treatment can be easily performed without requiring skilled techniques or complicated procedures.

[0015] According to the traction system described in (2) above of the present invention, by providing a fixing member that is transported by a transport device, the electric motor can be easily fixed inside the biological tube without requiring skilled techniques or complicated procedures.

[0016] According to the traction system described in (3) above of the present invention, by providing a sensor that is transported by a transport device, the traction force acting on a linear member and biological tissue within a biological tube can be easily and accurately detected without requiring skilled techniques or complicated procedures.

[0017] According to the traction system described in (4) above of the present invention, the accuracy of detecting the traction force acting on the linear member and biological tissue can be improved.

[0018] According to the traction system described in (5) above of the present invention, even when the linear member is wound up and unwound by the power of an electric motor, the sensor signal can be appropriately extracted regardless of the rotation of the linear member by providing a rotary connector.

[0019] According to the traction system described in (6) above of the present invention, by providing a detector that is transported by a transport device, the traction force detected based on the output of the sensor can be corrected with high accuracy.

[0020] According to the traction system described in (7) above of the present invention, by providing a sealing member, proper operation of the electric motor inside a biological tube can be ensured.

[0021] According to the traction system described in (8) above of the present invention, the complexity of the endoscope and overtube configuration is suppressed, and appropriate traction of biological tissue in endoscopic treatment can be easily performed without requiring skilled techniques or complicated procedures.

[0022] This diagram schematically shows the configuration of an endoscope system equipped with a traction system according to an embodiment of the present invention, illustrating the states in which the fixing member is located inside and outside the overtube. This is a perspective view showing the configuration of the traction device in the traction system according to an embodiment of the present invention. This is an exploded perspective view showing the configuration of the traction device in the traction system according to an embodiment of the present invention. This diagram schematically shows the flow of the first operating state (S1) and the second operating state (S2) in the traction system according to an embodiment of the present invention. This diagram schematically shows the flow of the third operating state (S3) and the fourth operating state (S4) in the traction system according to an embodiment of the present invention. This diagram schematically shows the flow of the fifth operating state (S5) and the sixth operating state (S6) in the traction system according to an embodiment of the present invention. This is a perspective view showing the configuration of the traction device in a first modified example of an embodiment of the present invention. This is a diagram showing a part of the traction device in a second modified example of an embodiment of the present invention, illustrating the change in the state of the traction device when a traction force is generated. This diagram schematically shows the configuration of an endoscope system equipped with a traction system according to a third modified example of an embodiment of the present invention. This is a perspective view showing a modified strain gauge (sensor) of the traction device in the traction system according to an embodiment of the present invention. This is a diagram showing the effect of a modified strain gauge (sensor) of the traction device in the traction system according to an embodiment of the present invention. (1) This figure shows the strain distribution in the sensing section when a load of 0.05 N is applied, as analyzed by SOLIDWORKS Simulation (manufactured by SOLIDWORKS). (2) This figure explains the sensing mechanism of the strain gauge (sensor). (3) This figure shows the size of the strain gauge (sensor) substrate used in this embodiment.

[0023] Hereinafter, a traction system according to an embodiment of the present invention will be described with reference to the accompanying drawings. Figure 1 is a schematic diagram showing the configuration of an endoscope system 1 equipped with the traction system 10 of the embodiment, and shows the state in which the fixing member 15 is located inside and outside the overtube 2. As shown in Figure 1, the traction system 10 of the embodiment is provided, for example, in an endoscope system 1. The endoscope system 1 is a so-called balloon endoscope system that is inserted into a biological tract such as the digestive tract. The endoscope system 1 comprises, for example, an overtube 2 with a balloon, an endoscope 3, an endoscope operation and observation system 4, a traction system 10, and an operating unit 5 of the traction system 10.

[0024] The outer shape of the overtube 2 is, for example, cylindrical. The overtube 2 is made of a flexible material such as urethane resin or silicone resin. The overtube 2 is an insertion aid for the endoscope 3 and the traction system 10. The overtube 2 guides the movement of the insertion portion and the traction system 10 within the biological tubule. For example, during insertion and removal from the biological tubule, the overtube 2 houses the traction system 10, described later, together with the insertion portion of the endoscope 3.

[0025] The endoscope 3 is a so-called flexible endoscope equipped with a flexible insertion section. The endoscope 3 includes, for example, an imaging unit, an illumination unit, a nozzle unit, and a treatment instrument guide unit, all located at the tip of the insertion section. The imaging unit captures images of the area to be observed. The illumination unit irradiates the area to be observed with illumination light. The nozzle unit sprays air, water, etc., supplied from the outside onto the area to be observed. The treatment instrument guide unit guides the advancement and withdrawal of various treatment instruments, such as clip placement devices and high-frequency knives.

[0026] The traction system 10 includes, for example, a traction device 11, a strain gauge 12, a traction lead wire 13, a ring member 14, a fixing member 15, an air tube 16, wiring 17, a connector 18, and a cable 19. Figure 2 is a perspective view showing the configuration of the traction device 11 in the traction system 10 of the embodiment. Figure 3 is an exploded perspective view showing the configuration of the traction device 11 in the traction system 10 of the embodiment. As shown in Figures 2 and 3, the traction device 11 includes, for example, an electric motor 21, an electric motor lead wire 22, a first case 23, a first sealing member 24, a reel member 25, a rotary connection connector 26, a rotary connection lead wire 27, a second case 28, and a second sealing member 29.

[0027] The electric motor 21 is, for example, a DC motor. The electric motor 21 is energized by electrically connected motor lead wires 22. The motor lead wires 22 are electrically connected to wiring 17 arranged on a fixing member 15, which will be described later. For example, the rotation direction and rotation speed of the electric motor 21 are controlled by a power supply switching operation corresponding to pulse width modulation control by the control unit of the endoscope operation and observation system 4.

[0028] The outer shape of the first case 23 is, for example, a bottomed cylindrical shape. The first case 23 houses the electric motor 21 inside. The outer shape of the first sealing member 24 is, for example, a disc shape. The first sealing member 24 is positioned between the first case 23 and the second case 28, which will be described later. The first sealing member 24 liquid-tightly seals the openings of the first case 23 and the second case 28.

[0029] The reel member 25 has an external shape that is, for example, a bobbin type with a pair of flanges at both ends in the axial direction of a cylindrical body. The traction lead wire 13 is wound around the reel member 25. The reel member 25 is connected to the electric motor 21 by, for example, mounting the rotating shaft 21a of the electric motor 21 into the shaft mounting holes 25a formed at the first ends at both ends in the axial direction. The reel member 25 winds up and unwinds the traction lead wire 13 using the rotational power output from the electric motor 21. The reel member 25 is connected to the rotary connector 26 by, for example, connecting the shaft portion 25b formed at the second ends at both ends in the axial direction to the rotating shaft 26a of the rotary connector 26, which will be described later. One end of the traction lead wire 13 wound around the reel member 25 protrudes from the inside of the reel member 25 to the outside via the shaft portion 25b and is electrically connected to the rotary connector 26.

[0030] The rotary connector 26 includes, for example, a slip ring. The rotary connector 26 electrically connects the traction lead wire 13, which is wound around the reel member 25 and rotates, with the rotary connector lead wire 27, which is fixed to the rotary connector 26. The rotary connector lead wire 27 is electrically connected to the wiring 17 arranged on the fixing member 15, which will be described later.

[0031] The second case 28 has an external shape, for example, that of a bottomed cylinder. The second case 28 houses the reel member 25 and the rotary connector 26 inside. The second sealing member 29 has an external shape, for example, that of a tube into which the traction lead wire 13 is inserted. The second sealing member 29 is made of a material that has water-repellent and sliding properties, such as fluororesin. The second sealing member 29 is positioned in a through hole provided in the second case 28 to guide the traction lead wire 13 to the outside. The second sealing member 29 slidably supports the traction lead wire 13 and liquid-tightly seals the through hole.

[0032] As shown in Figure 1, the strain gauge 12 is electrically and mechanically connected to the traction lead wire 13. The tip of the strain gauge 12, for example, the end opposite in the longitudinal direction to the base end to which the traction lead wire 13 is connected, is connected to the ring member 14. The strain gauge 12 outputs a signal corresponding to the change in electrical resistance value caused by the expansion and contraction strain of a resistor, such as a metal. The strain gauge 12 also outputs a signal corresponding to the expansion and contraction strain caused by the traction force acting between the traction lead wire 13 and the ring member 14.

[0033] The towing lead wire 13 is wound around the reel member 25. The first end of the towing lead wire 13 is electrically connected to the rotary connector 26 via the reel member 25. The second end of the towing lead wire 13 is electrically and mechanically connected to the strain gauge 12. The towing lead wire 13 ensures electrical conductivity to the strain gauge 12 and applies the towing force generated from the towing device 11 to the strain gauge 12. The towing lead wire 13 may also serve as the lead wire for the strain gauge 12. If it is used as the lead wire for the strain gauge 12, it is preferable to connect it to the drive power supply and detection circuit via a slip ring to prevent the lead wire from becoming entangled due to rotation when winding.

[0034] The outer shape of the ring member 14 is, for example, annular. The ring member 14 is formed of, for example, silicone resin. The ring member 14 is connected to a desired site, such as a lesion in biological tissue, by, for example, a clip of a treatment instrument delivered from the endoscope 3.

[0035] The fixing member 15 comprises, for example, a wire 15a and a bag 15b formed integrally. The outer shape of the wire 15a is, for example, spiral. The wire 15a is made of an elastic material such as a so-called superelastic alloy. For example, the shape of the wire 15a in its undeformed state is such that it can be inserted into the inside of the overtube 2.

[0036] The outer shape of the bag 15b is, for example, a strip. The bag 15b is made of a flexible material such as urethane resin or silicone resin. The bag 15b is connected to the air tube 16, which will be described later. The bag 15b expands when air is supplied from the outside by the air tube 16 and contracts when air is discharged to the outside by the air tube 16. By expanding, the bag 15b deforms the wire 15a so as to increase the diameter of the spiral shape. By contracting, the bag 15b returns the wire 15a to its original shape (i.e., the shape of the undeformed state). For example, the shape of the bag 15b in its unexpanded state is such that it can be inserted into the inside of the over tube 2.

[0037] For example, the wiring 17 described later is fixed to the inner circumference of the spirally arranged band-shaped bag 15b. For example, a traction device 11 is fixed to a predetermined location on the inner circumference of the bag 15b. For example, the bag 15b that expands in a biological tube such as the digestive tract is fixed inside the biological tube by its outer circumference being pressed against the inner wall W of the biological tube. The bag 15b fixed inside the biological tube fixes the position of the traction device 11 located on its inner circumference within the biological tube.

[0038] The air tube 16 connects, for example, an external pump to the bag body 15b. The wiring 17 is, for example, a flexible printed circuit board. The wiring 17 is arranged, for example, on the inner circumference of the bag body 15b of the fixing member 15. The wiring 17 is electrically connected to various lead wires of the traction device 11. The wiring 17 is electrically connected to the cable 19, for example, via a connector 18. The cable 19 is, for example, a flexible flat cable. The cable 19 electrically connects the external control unit to the wiring 17 via the connector 18.

[0039] An example of the operation of the endoscope system 1 of the embodiment is described below. Figure 4 is a schematic diagram showing the flow of the first operation state (S1) and the second operation state (S2) of the traction system 10 of the embodiment. Figure 5 is a schematic diagram showing the flow of the third operation state (S3) and the fourth operation state (S4) of the traction system 10 of the embodiment. Figure 6 is a schematic diagram showing the flow of the fifth operation state (S5) and the sixth operation state (S6) of the traction system 10 of the embodiment. The examples shown in Figures 4, 5, and 6 are examples of operation when the traction system 10 is inserted into the colon C.

[0040] First, as shown in the first operating state (S1) of Figure 4, the endoscope 3 and traction system 10 are inserted (transported) into the colon C by the overtube 2. Near the desired site A of biological tissue within the colon C, the tip of the endoscope 3 and the traction system 10 are sent out from inside the overtube 2. Air is supplied from the outside to the bag 15b of the fixing member 15 that has been sent into the colon C via the air tube 16. The fixing member 15 is fixed to the inner wall W of the colon C by the inflation of the bag 15b, thereby fixing the position of the traction device 11 positioned in the bag 15b within the colon C.

[0041] Next, as shown in the second operating state (S2) of Figure 4, the tip of the endoscope 3 is moved toward the ring member 14 of the strain gauge 12 located near the traction device 11. The clip placement device 3a is fed out from the tip of the endoscope 3 toward the ring member 14. The clip 3b at the tip of the clip placement device 3a holds the ring member 14.

[0042] Next, as shown in the third operating state (S3) of FIG. 5, the distal end portion of the endoscope 3 with the clip placement device 3a protruding is returned near the desired site A of the living tissue, thereby pulling out the traction lead wire 13 from the traction device 11 while moving the strain gauge 12 and the ring member 14 near the desired site A. The clip 3b at the distal end of the clip placement device 3a is moved from near the traction device 11 toward near the desired site A and then holds the desired site A together with the ring member 14. When the traction lead wire 13 is pulled out by the clip placement device 3a, the traction device 11 is controlled by the operation of the electric motor 21 controlled by the control unit of the endoscope operation observation system 4 based on the output of the strain gauge 12 to feed out the traction lead wire 13 without bending.

[0043] Next, as shown in the fourth operating state (S4) of FIG. 5, the clip 3b is separated from the clip placement device 3a. The desired site A held by the clip 3b together with the ring member 14 is supported by the traction force acting through the traction lead wire 13, the strain gauge 12, and the ring member 14 from the traction device 11. The clip placement device 3a from which the clip 3b has been separated is pulled back inside the endoscope 3. The high-frequency knife 3c is fed out from the distal end portion of the endoscope 3 toward the desired site A.

[0044] Next, as shown in the fifth operating state (S5) of FIG. 6, the traction device 11 pulls the desired site A to be excised by the high-frequency knife 3c in response to the control of the operation of the electric motor 21 by the control unit of the endoscope operation observation system 4. The control unit of the endoscope operation observation system 4 operates the electric motor 21 so that the traction force detected based on the output of the strain gauge 12 becomes the desired traction force. Next, as shown in the sixth operating state (S6) of FIG. 6, after the excision of the desired site A is completed, the distal end portion of the endoscope 3, the traction system 10, and the desired site A are housed inside the overtube 2. The distal end portion of the endoscope 3, the traction system 10, and the desired site A are transferred to the outside together with the overtube 2.

[0045] According to the traction system 10 of the above-described embodiment, by providing the overtube 2 and the endoscope 3 that transfer the traction device 11 and the traction lead wire 13 between the inside and the outside of the living body tube, appropriate traction of the living tissue in endoscopic treatment can be easily performed without requiring skilled techniques and cumbersome procedures. It is possible to suppress the complexity of the configurations of the overtube 2 and the endoscope 3.

[0046] By providing the fixing member 15 that is transferred between the inside and the outside of the living body tube, the traction device 11 can be easily fixed inside the living body tube without requiring skilled techniques and cumbersome procedures. By providing the strain gauge 12 that is transferred together with the traction device 11, the traction force acting on the traction lead wire 13 and the living tissue inside the living body tube can be easily and accurately detected without requiring skilled techniques and cumbersome procedures. The strain gauge 12 is connected to the traction lead wire 13, so that the detection accuracy of the traction force acting on the traction lead wire 13 and the living tissue can be improved.

[0047] By providing the first sealing member 24 and the second sealing member 29, proper operation of the traction device 11 inside the living body tube can be ensured.

[0048] (Modification) Hereinafter, a modification of the embodiment will be described. Regarding the same parts as those in the above-described embodiment, the same reference numerals will be given and the description will be omitted or simplified. In the above-described embodiment, the strain gauge 12 is connected to the traction lead wire 13 wound around the reel member 25, but it is not limited thereto. For example, the strain gauge 12 may be attached to the traction device 11. FIG. 7 is a perspective view showing the configuration of the traction device 11A of the first modification of the embodiment.

[0049] As shown in Figure 7, the first modified traction device 11A includes a strain gauge 12 located inside the first case 23 and a wire 31 provided in place of the traction lead wire 13 of the embodiment. In the first modified traction device 11A, the rotary connector 26 of the embodiment is omitted. The first modified traction device 11A includes, for example, an electric motor 21, an electric motor lead wire 22, a first case 23, a first sealing member 24, a reel member 25, a wire 31, a third case 32, and a third sealing member 33.

[0050] The wire 31 is wound around the reel member 25. The first end of the wire 31 is fixed to the reel member 25, and the second end is connected to the ring member 14. The outer shape of the third case 32 is, for example, a bottomed cylindrical shape. The third case 32 houses the reel member 25 inside. The first sealing member 24 is positioned between the first case 23 and the third case 32. The first sealing member 24 liquid-tightly seals the openings of the first case 23 and the third case 32, respectively.

[0051] The outer shape of the third sealing member 33 is, for example, cylindrical, into which the wire 31 is inserted. The third sealing member 33 is made of a material that has water-repellent and sliding properties, such as fluororesin. The third sealing member 33 is positioned in a through hole provided in the third case 32 to guide the wire 31 to the outside. The third sealing member 33 slidably supports the wire 31 and liquid-tightly seals the through hole.

[0052] In the first modified example described above, a spacer may be placed between the strain gauge 12 and the electric motor 21. Figure 8 is a cross-sectional view showing a part of the traction device 11B of the second modified example of the embodiment, and is a diagram showing the change in state of the traction device 11B when a traction force is generated. As shown in Figure 8, the traction device 11B of the second modified example comprises, for example, an electric motor 21, an electric motor lead wire 22, a first case 23, a first sealing member 24, a reel member 25, a wire 31, a third case 32, a third sealing member 33, a first spacer 34, and a second spacer 35.

[0053] The first spacer 34 and the second spacer 35 are positioned between the strain gauge 12, which is mounted on the electric motor 21, and the inner wall of the first case 23. The first spacer 34 is made of an elastic material with relatively high rigidity, and the second spacer 35 is made of an elastic material with relatively low rigidity. The second spacer 35 is positioned along the axial direction of the electric motor 21, closer to the reel member 25 than the first spacer 34. By configuring the first spacer 34 and the second spacer 35 in this way, the strain gauge 12 is in a so-called cantilevered state, so that in the second modification, the strain gauge 12 outputs a signal more accurately in response to changes in the attitude of the electric motor 21 caused, for example, by the tensile force acting on the wire 31. Alternatively, only the first spacer 34 may be provided as an air gap without the second spacer 35, in which case the strain gauge 12 may be attached to a substrate that functions as a cantilever beam. Alternatively, the base of the substrate, which functions as a cantilever beam, may be connected to the side surface of the first case 23 without providing both the first spacer 34 and the second spacer 35.

[0054] In the first and second modified examples described above, the traction system 10 may, for example, include a detector for detecting the orientation of the wire 31. Figure 9 is a schematic diagram showing the configuration of an endoscope system 1 equipped with a traction system 10A of a third modified example of the embodiment. As shown in Figure 9, the traction system 10A of the third modified example of the embodiment includes a detector 36 for detecting the orientation of the wire 31. The detector 36 is, for example, an imaging device for imaging the orientation of the wire 31. The detector 36 is, for example, fixed to the inner circumference of the bag body 15b of the fixing member 15 and electrically connected to the wiring 17. In the third modified example, the operation unit 5 of the traction system 10 corrects the traction force detected based on the output of the strain gauge 12 in accordance with the signal output from the detector 36. The operation unit 5 corrects the difference between the traction force detected based on the output of the strain gauge 12 in the traction device 11A and the traction force acting on the ring member 14 at the tip of the wire 31.

[0055] In the embodiments described above, the fixing member 15 is said to include a wire 15a and a bag 15b formed integrally, but it is not limited to this. For example, the fixing member 15 may include an adhesive for bonding and fixing the traction device 11 inside the biological tube, or a clip or other device for mechanical fixing. Figure 10 is a perspective view showing a modified strain gauge 12 of the traction device in the traction system of an embodiment of the present invention, and Figure 11 is a diagram showing the effect of the modified strain gauge 12. The strain gauge 12 is preferably used for measurement by "tensile force", but if the substrate to which the strain gauge 12 is attached is thick, the strain gauge hardly stretches and measurement is not possible, so it is necessary to make the substrate sufficiently thin and to take measures such as completely removing the substrate on the back side of the strain gauge 12, but there is a problem that it becomes easily damaged with use. Therefore, by shaping the strain gauge 12 so that both ends are bent, the tensile force is converted into a bending (warping) force, and by measuring it as "bending (due to load / pressure)," it is possible to achieve both the robustness of the sensor and the measurement sensitivity and accuracy, especially around 0.05 N, which is the assumed load in this invention.

[0056] The embodiments of the present invention are presented as examples and are not intended to limit the scope of the invention. These embodiments can be carried out in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their variations are included in the scope and spirit of the invention, as well as in the claims and their equivalents.

[0057] 1 Endoscope system 2 Overtube (transfer device) 3 Endoscope (transfer device) 4 Endoscope operation and observation system 5 Operation unit (operation unit for traction systems 10, 10A) 10, 10A traction system 11 Traction device 12 Strain gauge (sensor) 13 Traction lead wire (linear member) 14 Ring member 15 Fixing member 16 Air tube 17 Wiring 18 Connector 19 Cable 21 Electric motor 22 Lead wire for electric motor 23 First case 24 First sealing member 25 Reel member 26 Rotary connection connector 27 Rotary connection lead wire 28 Second case 29 Second sealing member 31 Wire (linear member) 32 Third case 33 Third sealing member 34 First spacer 35 Second spacer 36 Detector.

Claims

1. A traction system comprising: a linear member connected to biological tissue; an electric motor that generates a traction force acting on the linear member; and a transport device that transports the traction device having the linear member and the electric motor between inside and outside a biological tube.

2. The traction system according to claim 1, comprising a fixing member for fixing the electric motor inside the biological tube, wherein the transport device transports the traction device and the fixing member between inside and outside the biological tube.

3. The traction system according to claim 2, comprising a sensor for detecting a state quantity related to the traction force acting on the linear member, wherein the transport device transports the traction device, the fixing member, and the sensor between inside and outside the biological tube.

4. The traction system according to claim 3, wherein the sensor is connected to the linear member.

5. The traction system according to claim 4, wherein the traction device comprises a rotary connector for extracting the output of the sensor from the linear member.

6. The traction system according to claim 3, comprising a detector that detects a state quantity related to the attitude of the linear member in order to correct the traction force detected based on the output of the sensor, wherein the transport device transports the traction device, the fixing member, the sensor and the detector between inside and outside the biological tube.

7. The traction system according to any one of claims 1 to 6, further comprising a sealing member for liquid-tight sealing of the inside of the electric motor.

8. The traction system according to claim 7, wherein the transport device comprises an endoscope and an overtube.

Images