Continuum Robot

Abstract

To provide a continuum robot which has improved durability, comprises a linear member and materializes sooth movement of the linear member.SOLUTION: A continuum robot is provided, comprising; a curvable body (11) having a linear member (W) provided along a first pitch circle; and a motor (M) which has an output shaft (Ma) provided along a second pitch circle formed by offsetting the first pitch circle outside, drives the linear member (W) to curve the curvable body. The robot further comprises: an intermediate support shaft (21cs) which is provided along a third pitch circle formed by offsetting the first pitch circle outside and offsetting the second pitch circle inside; first connection members (21cb, 21ch) which connect a to-be-held portion (Wa) of an end portion of the linear member (W) and the intermediate support shaft (21cs); and a second connection member (21ct) which connects the intermediate support shaft (21cs) and the output shaft (Ma), converts rotation of the output shaft (Ma) into a linear movement, to thereby transfer the intermediate support shaft (21cs).SELECTED DRAWING: Figure 18

Description

Technical Field

[0001] The present invention relates to a continuum robot.

Background Art

[0002] Patent Document 1 discloses a continuum robot including a bendable body having drive wires and an actuator, configured to operate the bendable body by moving the drive wires backward and forward by the actuator.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In a continuum robot that drives and moves a plurality of wires arranged along a pitch circle, a plurality of motors are required as drive sources for the wires. In this case, as in Patent Document 1, in order to avoid interference between the motors, the motor shafts are arranged at positions offset outward in the radial direction of the pitch circle with respect to the ends of the wires, and the ends of the wires are connected to the motor shafts via a traction device (corresponding to the tractor in the present application). However, in this configuration, when the distance between the end of the wire and the motor shaft increases, the moment applied to the tractor during driving increases. Therefore, the wear between the motor shaft and the tractor increases, resulting in poor durability and possibly hindering the smooth movement of the wire. Also, if the wire is guided so as to bend outward in the radial direction of the pitch circle in order to reduce the distance between the end of the wire and the motor shaft, a frictional force in a direction that hinders the movement of the wire during driving is generated. Therefore, there is a loss in the transmission of the driving force to the wire, and the smooth movement of the wire may be hindered.

[0005] The present invention has been made in view of the above points, and an object thereof is to provide a continuum robot that improves durability and realizes smooth movement of a linear member.

Means for Solving the Problems

[0006] The continuum robot of the present invention includes a bendable body having a plurality of linear members provided along a first pitch circle, and a plurality of output shafts provided along a second pitch circle that is offset outward from the first pitch circle. Each of the plurality of linear members is driven by a plurality of motors that bend the bendable body. The continuum robot is provided with a plurality of intermediate support shafts provided along a third pitch circle that is offset outward from the first pitch circle and offset inward from the second pitch circle, and a plurality of first connection members that connect the ends of the plurality of linear members and the plurality of intermediate support shafts, respectively. The plurality of intermediate support shafts and the plurality of output shafts are connected to each other, and a plurality of second connection members that convert the rotation of the output shaft into linear motion and linearly move the intermediate support shaft are provided.

Effects of the Invention

[0007] According to the present invention, it is possible to provide a continuum robot that improves durability and realizes smooth movement of a linear member.

Brief Description of the Drawings

[0008]

Figure 1

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Embodiments for Carrying Out the Invention

[0009] Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the dimensions, materials, shapes, arrangements, etc. of the components described in this embodiment should be appropriately changed according to the configuration of the device to which the present invention is applied and various conditions. <Medical System and Medical Device> Using FIGS. 1 and 2, the medical system 1A and the medical device (continuum robot) 1 will be described. FIG. 1 is an overall view of the medical system 1A. FIG. 2 is a perspective view showing the medical device 1 and the support base 2. Medical system 1A includes a medical device 1, a support base 2 for attaching the medical device 1, and a control device 3 for controlling the medical device 1. In this embodiment, the medical system 1A includes a monitor 4 as a display device.

[0010] The medical device 1 includes a catheter unit (curvable unit) 100 including a catheter 11 as a curvable body, and a base unit (drive unit, wearable unit) 200. The catheter unit 100 is configured to be detachable from the base unit 200. In this embodiment, the user of the medical system 1A and the medical device 1 can perform operations such as observing the inside of the subject, collecting various specimens from the inside of the subject, and treating the inside of the subject by inserting the catheter 11 into the inside of the subject. As one embodiment, the user can insert the catheter 11 into the inside of a patient as the subject. Specifically, by inserting through the patient's oral cavity or nasal cavity into the bronchus, operations such as observing, collecting, and excising lung tissue can be performed. The catheter 11 can be used as a guide (sheath) for guiding medical instruments for performing the above operations. Examples of medical instruments (tools) include endoscopes, forceps, ablation devices, etc. Also, the catheter 11 itself may have the function as the above medical instrument.

[0011] In this embodiment, the control unit 3 includes an arithmetic unit 3a and an input device 3b. The input device 3b receives commands and inputs for operating the catheter 11. The arithmetic unit 3a includes a storage for storing programs and various data for controlling the catheter, a random access memory, and a central processing unit for executing the program. Also, the control unit 3 may include an output unit for outputting a signal for displaying an image on the monitor 4.

[0012] As shown in FIG. 2, in this embodiment, the medical device 1 is electrically connected to the control unit 3 via the cable 5 that connects the base unit 200 of the medical device 1 and the support base 2 and the support base 2. Note that the medical device 1 and the control unit 3 may be directly connected by a cable. The medical device 1 and the control unit 3 may be wirelessly connected.

[0013] The medical device 1 is detachably attached to the support base 2 via the base unit 200. More specifically, in the medical device 1, the attachment portion 200a of the base unit 200 is detachably attached to the moving stage (receiving portion) 2a of the support base 2. Even when the attachment portion 200a of the medical device 1 is removed from the moving stage 2a, the connection between the medical device 1 and the control unit 3 is maintained so that the medical device 1 can be controlled by the control unit 3. In this embodiment, even when the attachment portion 200a of the medical device 1 is removed from the moving stage 2a, the medical device 1 and the support base 2 are connected by the cable 5.

[0014] The user can manually move the medical device 1 in a state where the medical device 1 is removed from the support base 2 (a state where the medical device 1 is removed from the moving stage 2a) and insert the catheter 11 into the subject. The user can use the medical device 1 in a state where the catheter 11 is inserted into the subject and the medical device 1 is attached to the support base 2. Specifically, when the medical device 1 is attached to the moving stage 2a, the medical device 1 moves as the moving stage 2a moves. Then, an operation of moving in the direction of inserting the catheter 11 into the subject and an operation of moving in the direction of pulling out the catheter 11 from the subject are performed. The movement of the moving stage 2a is controlled by the control unit 3.

[0015] The medical device 1 includes a wire drive unit (linear member drive unit, line drive unit, main body drive unit) 300 for driving the catheter 11. In this embodiment, the medical device 1 is a robotic catheter device that drives the catheter 11 by the wire drive unit 300 controlled by the control unit 3.

[0016] The control device 3 can control the wire drive unit 300 to perform an operation of bending the catheter 11. In this embodiment, the wire drive unit 300 is built into the base unit 200. More specifically, the base unit 200 includes a base housing 200f that houses the wire drive unit 300. That is, the base unit 200 includes the wire drive unit 300. The wire drive unit 300 and the base unit 200 together can be called a catheter drive device (base device, main body).

[0017] Regarding the extending direction of the catheter 11, the end where the tip of the catheter 11 inserted into the subject is located is called the distal end. In the extending direction of the catheter 11, the opposite side of the distal end is called the proximal end. The catheter unit 100 has a proximal end cover 16 that covers the proximal end side of the catheter 11. The proximal end cover 16 has a tool hole 16a. A medical instrument can be inserted into the catheter 11 through the tool hole 16a.

[0018] As described above, in this embodiment, the catheter 11 has a function as a guide device for guiding a medical instrument to a desired position inside the subject. For example, with an endoscope inserted into the catheter 11, the catheter 11 is inserted to a target position inside the subject. At this time, at least one of a manual operation by the user, the movement of the moving stage 2a, and the driving of the catheter 11 by the wire drive unit 300 is used. After the catheter 11 reaches the target position, the endoscope is withdrawn from the catheter 11 through the tool hole 16a. Then, a medical instrument is inserted through the tool hole 16a, and operations such as collecting various specimens from inside the subject and treating the inside of the subject are performed.

[0019] As will be described later, the catheter unit 100 is removably attached to a catheter driving device (base device, main body), more specifically, the base unit 200. After the medical device 1 has been used, the user can remove the catheter unit 100 from the base unit 200, attach a new catheter unit 100 to the base unit 200, and use the medical device 1 again.

[0020] As shown in FIG. 2, the medical device 1 has an operation unit 400. In the present embodiment, the operation unit 400 is provided in the catheter unit 100. The operation unit 400 is operated by the user when the catheter unit 100 is fixed to the base unit 200 or removed from the base unit 200.

[0021] <Catheter> The catheter 11 as a bendable body will be described with reference to FIG. 3. FIG. 3 is an explanatory diagram of the catheter 11. FIG. 3(a) is a diagram for explaining the entire catheter 11. FIG. 3(b) is an enlarged view of the catheter 11. The catheter 11 includes a bending portion (bendable body, catheter main body) 12 and a bending drive portion (catheter drive portion) 13 configured to bend the bending portion 12. The bending drive portion 13 is configured to receive the driving force of the wire drive portion 300 via a connecting device 21 described later and bend the bending portion 12. The catheter 11 extends along the insertion direction of the catheter 11 with respect to the target. The extending direction (longitudinal direction) of the catheter 11 is the same as the extending direction (longitudinal direction) of the bending portion 12 and the extending direction (longitudinal direction) of the first to ninth drive wires (W11 to W33) described later.

[0022] The bending drive unit 13 includes a plurality of drive wires (drive lines, linear members, linear actuators) connected to the bending unit 12. Specifically, the bending drive unit 13 includes a first drive wire W11, a second drive wire W12, a third drive wire W13, a fourth drive wire W21, a fifth drive wire W22, a sixth drive wire W23, a seventh drive wire W31, an eighth drive wire W32, and a ninth drive wire W33.

[0023] Each of the first to ninth drive wires (W11 to W33) includes a held portion (held shaft, rod) Wa. Specifically, the first drive wire W11 includes a first held portion Wa11. The second drive wire W12 includes a second held portion Wa12. The third drive wire W13 includes a third held portion Wa13. The fourth drive wire W21 includes a fourth held portion Wa21. The fifth drive wire W22 includes a fifth held portion Wa22. The sixth drive wire W23 includes a sixth held portion Wa23. The seventh drive wire W31 includes a seventh held portion Wa31. The eighth drive wire W32 includes an eighth held portion Wa32. The ninth drive wire W33 includes a ninth held portion Wa33. In this embodiment, each of the first to ninth held portions (Wa11 to Wa33) has the same shape.

[0024] Each of the first to ninth drive wires (W11 to W33) includes a flexible wire body (line body, linear body) Wb. Specifically, the first drive wire W11 includes a first wire body Wb11. The second drive wire W12 includes a second wire body Wb12. The third drive wire W13 includes a third wire body Wb13. The fourth drive wire W21 includes a fourth wire body Wb21. The fifth drive wire W22 includes a fifth wire body Wb22. The sixth drive wire W23 includes a sixth wire body Wb23. The seventh drive wire W31 includes a seventh wire body Wb31. The eighth drive wire W32 includes an eighth wire body Wb32. The ninth drive wire W33 includes a ninth wire body Wb33. In this embodiment, each of the first to third wire bodies (Wb11 to Wb13) has the same shape. Each of the fourth to sixth wire bodies (Wb21 to Wb23) has the same shape. Each of the seventh to ninth wire bodies (Wb31 to Wb33) has the same shape. In this embodiment, the first to ninth wire bodies (Wb11 to Wb33) have the same shape except for their lengths.

[0025] The first to ninth held portions (Wa11 to Wa33) are fixed to the first to ninth wire bodies (Wb11 to Wb33) at the proximal ends of the first to ninth wire bodies (Wb11 to Wb33). The first to ninth drive wires (W11 to W33) are inserted into and fixed to the curved portion 12 via the wire guide 17. In this embodiment, the material of each of the first to ninth drive wires (W11 to W33) is metal. However, the material of each of the first to ninth drive wires (W11 to W33) may be resin. The material of each of the first to ninth drive wires (W11 to W33) may include metal and resin. Any one of the first to ninth drive wires (W11 to W33) can be referred to as the drive wire W. In this embodiment, each of the first to ninth drive wires (W11 to W33) has the same shape except for the lengths of the first to ninth wire bodies (Wb11 to Wb33).

[0026] In this embodiment, the curved portion 12 is a tubular member having flexibility and provided with a passage Ht for inserting a medical instrument. The wall surface of the bending portion 12 is provided with a plurality of wire holes for passing the first to ninth drive wires (W11 to W33) respectively. Specifically, the wall surface of the bending portion 12 is provided with a first wire hole Hw11, a second wire hole Hw12, a third wire hole Hw13, a fourth wire hole Hw21, a fifth wire hole Hw22, a sixth wire hole Hw23, a seventh wire hole Hw31, an eighth wire hole Hw32, and a ninth wire hole Hw33. Each of the first to ninth wire holes Hw (Hw11 to Hw33) corresponds to each of the first to ninth drive wires (W11 to W33). The number after the symbol Hw indicates the number of the corresponding drive wire. For example, the first drive wire W11 is inserted into the first wire hole Hw11. Any one of the first to ninth wire holes (Hw11 to Hw33) can be referred to as a wire hole Hw. In this embodiment, each of the first to ninth wire holes (Hw11 to Hw33) has the same shape.

[0027] The bending portion 12 has an intermediate region 12a and a bending region 12b. The bending region 12b is arranged at the distal end of the bending portion 12, and a first guide ring J1, a second guide ring J2, and a third guide ring J3 are arranged in the bending region 12b. The bending region 12b refers to a region where the magnitude and direction of the bending of the bending portion 12 can be controlled by moving the first guide ring J1, the second guide ring J2, and the third guide ring J3 by the bending drive unit 13. FIG. 3(b) is drawn with a part of the bending portion 12 covering the first to third guide rings (J1 to J3) omitted. In this embodiment, the bending portion 12 is provided with a plurality of auxiliary rings (not shown). In the bending region 12b, the first guide ring J1, the second guide ring J2, and the third guide ring J3 are fixed to the wall surface of the bending portion 12. In this embodiment, the plurality of auxiliary rings are arranged on the proximal side of the first guide ring J1, between the first guide ring J1 and the second guide ring J2, and between the second guide ring J2 and the third guide ring J3.

[0028] The medical instrument is guided to the tip of the catheter 11 by the passage Ht, the first to third guide rings (J1 to J3), and the plurality of auxiliary rings.

[0029] Each of the first to ninth drive wires (W11 to W33) is fixed to each of the first to third guide rings (J1 to J3) through the intermediate region 12a. Specifically, the first drive wire W11, the second drive wire W12, and the third drive wire W13 penetrate through a plurality of auxiliary rings and are fixed to the first guide ring J1. The fourth drive wire W21, the fifth drive wire W22, and the sixth drive wire W23 penetrate through the first guide ring J1 and a plurality of auxiliary rings and are fixed to the second guide ring J2. The seventh drive wire W31, the eighth drive wire W32, and the ninth drive wire W33 penetrate through the first guide ring J1, the second guide ring J2, and a plurality of auxiliary rings and are fixed to the third guide ring J3.

[0030] The medical device 1 can bend the bending portion 12 in a direction intersecting the extending direction of the catheter 11 by driving the bending drive portion 13 by the wire drive portion 300. Specifically, by moving each of the first to ninth drive wires (W11 to W33) in the extending direction of the bending portion 12, the bending region 12b of the bending portion 12 can be bent in a direction intersecting the extending direction via the first to third guide rings (J1 to J3). The user can insert the catheter 11 to the target internal target portion by using at least one of the movement of the medical device 1 by hand or by the moving stage 2a and the bending of the bending portion 12.

[0031] In this embodiment, the first to third guide rings (J1 to J3) are moved by the first to ninth drive wires (W11 to W33) to bend the bending portion 12, but the present invention is not limited to this configuration. Any one or two of the first to third guide rings (J1 to J3) and the drive wires fixed thereto may be omitted. For example, the catheter 11 may have a configuration in which the first to sixth drive wires (W11 to W23) and the first to second guide rings (J1 to J2) are omitted, and only the seventh to ninth drive wires (W31 to W33) and the third guide ring J3 are provided. Further, the catheter 11 may have a configuration in which the first to third drive wires (W11 to W13) and the first guide ring J1 are omitted, and only the fourth to ninth drive wires (W21 to W33) and the second to third guide rings (J2 to J3) are provided. Further, the catheter 11 may be configured to drive one guide ring with two drive wires. Also in this case, the number of guide rings may be one or more than one.

[0032] <Catheter unit> The catheter unit 100 will be described with reference to FIG. 4. FIG. 4 is an explanatory view of the catheter unit 100. FIG. 4(a) is an explanatory view of the catheter unit 100 in a state where a wire cover 14 described later is in the covering position. FIG. 4(b) is an explanatory view of the catheter unit 100 in a state where the wire cover 14 described later is in the retracted position. The catheter unit 100 includes a catheter 11 having a bending portion 12 and a bending drive portion 13, and a proximal end cover 16 that supports the proximal end of the catheter 11. The catheter unit 100 includes a cover (wire cover) 14 that covers and protects the first to ninth drive wires (W11 to W33) as a plurality of drive wires.

[0033] The catheter unit 100 is detachable from the base unit 200 along the attachment / detachment direction DE. The attachment direction of the catheter unit 100 to the base unit 200 and the detachment direction of the catheter unit 100 from the base unit 200 are parallel to the attachment / detachment direction DE. The proximal end cover (frame body, bending portion housing, catheter housing) 16 is a cover that covers a part of the catheter 11. The proximal end cover 16 has a tool hole 16a for inserting a medical instrument into the passage Ht of the bending portion 12.

[0034] The wire cover 14 is provided with a plurality of wire cover holes (cover holes) for passing through the first to ninth drive wires (W11 to W33) respectively. The wire cover 14 is provided with a first wire cover hole 14a11, a second wire cover hole 14a12, a third wire cover hole 14a13, a fourth wire cover hole 14a21, a fifth wire cover hole 14a22, a sixth wire cover hole 14a23, a seventh wire cover hole 14a31, an eighth wire cover hole 14a32, and a ninth wire cover hole 14a33. Each of the first to ninth wire cover holes (14a11 to 14a33) corresponds to each of the first to ninth drive wires (W11 to W33). The number after the symbol 14a indicates the number of the corresponding drive wire. For example, the first drive wire W11 is inserted into the first wire cover hole 14a11. Any one of the first to ninth wire cover holes (14a11 to 14a33) can be referred to as the wire cover hole 14a. In this embodiment, each of the first to ninth wire cover holes (14a11 to 14a33) has the same shape.

[0035] The wire cover 14 can move between a cover position (see FIG. 14(a)) that covers the first to ninth drive wires (W11 to W33) and a retracted position (see FIG. 14(b)) that retracts from the cover position. The retracted position can also be referred to as an exposed position that exposes the first to ninth drive wires (W11 to W33). Before the catheter unit 100 is attached to the base unit 200, the wire cover 14 is located at the cover position. When the catheter unit 100 is attached to the base unit 200, the wire cover 14 moves from the cover position to the retracted position along the attachment / detachment direction DE.

[0036] In this embodiment, after the wire cover 14 moves from the cover position to the retracted position, it is fixed at the retracted position. Therefore, even after the catheter unit 100 is removed from the base unit 200 after the catheter unit 100 is attached to the base unit 200, the wire cover 14 is fixed at the retracted position. However, after moving the wire cover 14 from the cover position to the retracted position, it may be configured to return to the cover position. For example, the catheter unit 100 may include a biasing member that biases the wire cover 14 from the retracted position toward the cover position. In this case, after the catheter unit 100 is attached to the base unit 200, when the catheter unit 100 is removed from the base unit 200, the wire cover 14 is moved from the retracted position to the cover position. When the wire cover 14 is in the retracted position, the first to ninth held portions (Wa11 to Wa33) of the first to ninth drive wires (W11 to W33) protrude with respect to the wire cover 14. As a result, the connection between the bending drive unit 13 and a connection device 21 described later is allowed. When the wire cover 14 is in the retracted position, the first to ninth held portions (Wa11 to Wa33) of the first to ninth drive wires (W11 to W33) protrude from the first to ninth wire cover holes (14a11 to 14a33). More specifically, the first to ninth held portions (Wa11 to Wa33) protrude from the first to ninth wire cover holes (14a11 to 14a33) in the mounting direction Da described later.

[0037] As shown in FIG. 4(b), each of the first to ninth drive wires (W11 to W33) is arranged along a circle (virtual circle) having a predetermined radius. In the present application, this circle is referred to as a pitch circle. In the present embodiment, the catheter unit 100 has a key shaft (key, catheter-side key) 15. In the present embodiment, the key shaft 15 extends in the attachment / detachment direction DE. The wire cover 14 is provided with a shaft hole 14b through which the key shaft 15 passes. The key shaft 15 can engage with a key receiving portion 22 described later. By engaging the key shaft 15 with the key receiving portion 22, the movement of the catheter unit 100 with respect to the base unit 200 is restricted within a predetermined range in the circumferential direction of the circle (virtual circle) along which the first to ninth drive wires (W11 to W33) are arranged. In this embodiment, when viewed in the attachment / detachment direction DE, the first to ninth drive wires (W11 to W33) are arranged outside the key shaft 15 so as to surround the key shaft 15. In other words, the key shaft 15 is arranged inside the radial direction of a circle (virtual circle) in which the first to ninth drive wires (W11 to W33) are arranged.

[0038] In this embodiment, the catheter unit 100 includes an operation unit 400. The operation unit 400 is configured to be movable (rotatable) with respect to the proximal end cover 16 and the bending drive unit 13. The operation unit 400 is rotatable around the rotation axis 400r. The rotation axis 400r of the operation unit 400 extends in the attachment / detachment direction DE. In a state where the catheter unit 100 is attached to the base unit 200, the operation unit 400 is configured to be movable (rotatable) with respect to the base unit 200. More specifically, the operation unit 400 is configured to be movable (rotatable) with respect to the base housing 200f, the wire drive unit 300, and a connection device 21 described later.

[0039] <Base Unit> The base unit 200 and the wire drive unit 300 will be described with reference to FIG. 5. FIG. 5 is an explanatory diagram of the base unit 200 and the wire drive unit 300. FIG. 5(a) is a perspective view showing the internal structure of the base unit 200. FIG. 5(b) is a side view showing the internal structure of the base unit 200. FIG. 5(c) is a view of the base unit 200 seen along the attachment / detachment direction DE.

[0040] As described above, the medical device 1 has a base unit 200 and a wire drive unit 300. In this embodiment, the wire drive unit 300 is housed in the base housing 200f and provided inside the base unit 200. In other words, the base unit 200 includes the wire drive unit 300. The wire drive unit 300 has a plurality of drive sources (motors). In this embodiment, the wire drive unit 300 includes a first drive source M11, a second drive source M12, a third drive source M13, a fourth drive source M21, a fifth drive source M22, a sixth drive source M23, a seventh drive source M31, an eighth drive source M32, and a ninth drive source M33. Among the first to ninth drive sources (M11 to M33), any one of them can be referred to as the drive source M. In this embodiment, each of the first to ninth drive sources (M11 to M33) has the same configuration.

[0041] The base unit 200 includes a connecting device 21. The connecting device 21 is housed in the base housing 200f. The connecting device 21 is connected to the wire drive unit 300. The connecting device 21 has a plurality of connecting parts. In this embodiment, the connecting device 21 includes a first connecting part 21c11, a second connecting part 21c12, a third connecting part 21c13, a fourth connecting part 21c21, a fifth connecting part 21c22, a sixth connecting part 21c23, a seventh connecting part 21c31, an eighth connecting part 21c32, and a ninth connecting part 21c33. Among the first to ninth connecting parts (21c11 to 21c33), any one of them can be referred to as the connecting part 21c. In this embodiment, each of the first to ninth connecting parts (21c11 to 21c33) has the same configuration.

[0042] Each of the plurality of connecting parts is connected to each of the plurality of drive sources and is driven by each of the plurality of drive sources. Specifically, the first connecting part 21c11 is connected to the first drive source M11 and is driven by the first drive source M11. The second connecting part 21c12 is connected to the second drive source M12 and is driven by the second drive source M12. The third connecting part 21c13 is connected to the third drive source M13 and is driven by the third drive source M13. The fourth connecting part 21c21 is connected to the fourth drive source M21 and is driven by the fourth drive source M21. The fifth connecting part 21c22 is connected to the fifth drive source M22 and is driven by the fifth drive source M22. The sixth connecting part 21c23 is connected to the sixth drive source M23 and is driven by the sixth drive source M23. The seventh connecting part 21c31 is connected to the seventh drive source M31 and is driven by the seventh drive source M31. The eighth connecting part 21c32 is connected to the eighth drive source M32 and is driven by the eighth drive source M32. The ninth connecting part 21c33 is connected to the ninth drive source M33 and is driven by the ninth drive source M33.

[0043] As will be described later, a bending drive part 13 including the first to ninth drive wires (W11 to W33) is connected to the connecting device 21. The bending drive part 13 receives the driving force of the wire drive part 300 via the connecting device 21 and bends the bending part 12. The drive wire W is connected to the connecting part 21c via the held part Wa. Each of the plurality of drive wires is connected to each of the plurality of connecting parts. Specifically, the first held portion Wa11 of the first drive wire W11 is connected to the first connecting portion 21c11. The second held portion Wa12 of the second drive wire W12 is connected to the second connecting portion 21c12. The third held portion Wa13 of the third drive wire W13 is connected to the third connecting portion 21c13. The fourth held portion Wa21 of the fourth drive wire W21 is connected to the fourth connecting portion 21c21. The fifth held portion Wa22 of the fifth drive wire W22 is connected to the fifth connecting portion 21c22. The sixth held portion Wa23 of the sixth drive wire W23 is connected to the sixth connecting portion 21c23. The seventh held portion Wa31 of the seventh drive wire W31 is connected to the seventh connecting portion 21c31. The eighth held portion Wa32 of the eighth drive wire W32 is connected to the eighth connecting portion 21c32. The ninth held portion Wa33 of the ninth drive wire W33 is connected to the ninth connecting portion 21c33.

[0044] The base unit 200 has a base frame 25. The base frame 25 is provided with a plurality of insertion holes for passing each of the first to ninth drive wires (W11 to W33). The base frame 25 is provided with a first insertion hole 25a11, a second insertion hole 25a12, a third insertion hole 25a13, a fourth insertion hole 25a21, a fifth insertion hole 25a22, a sixth insertion hole 25a23, a seventh insertion hole 25a31, an eighth insertion hole 25a32, and a ninth insertion hole 25a33. Each of the first to ninth insertion holes (25a11 to 25a33) corresponds to each of the first to ninth drive wires (W11 to W33). The number after the symbol 25a indicates the number of the corresponding drive wire. For example, the first drive wire W11 is inserted into the first insertion hole 25a11. Any one of the first to ninth insertion holes (25a11 to 25a33) can be referred to as the insertion hole 25a. In this embodiment, each of the first to ninth insertion holes (25a11 to 25a33) has the same shape.

[0045] The base frame 25 is provided with a mounting opening 25b into which the wire cover 14 is inserted. At the bottom of the mounting opening 25b, the first to ninth insertion holes (25a11 to 25a33) are arranged.

[0046] Furthermore, the base unit 200 includes a motor frame 200b, a first bearing frame 200c, a second bearing frame 200d, and a third bearing frame 200e.

[0047] The base frame 25 has a key receiving portion (key hole, base-side key, main body-side key) 22 for receiving the key shaft 15. When the key shaft 15 engages with the key receiving portion 22, the catheter unit 100 is attached to the base unit 200 in the correct phase. When the key shaft 15 engages with the key receiving portion 22, the movement of the catheter unit 100 relative to the base unit 200 is restricted within a predetermined range in the circumferential direction of the circle (virtual circle) in which the first to ninth drive wires (W11 to W33) are arranged. As a result, each of the first to ninth drive wires (W11 to W33) engages with each of the corresponding first to ninth insertion holes (25a11 to 25a33) and each of the corresponding first to ninth connecting portions (21c11 to 21c33). In other words, it is prevented that the drive wire W engages with a non-corresponding insertion hole 25 and a non-corresponding connecting portion 21.

[0048] By engaging the key shaft 15 with the key receiving portion 22, the user can correctly connect each of the first to ninth drive wires (W11 to W33) to each of the first to ninth connecting portions (21c11 to 21c33). Therefore, the user can easily attach the catheter unit 100 to the base unit 200. In this embodiment, the key shaft 15 has a convex portion protruding in a direction intersecting the attachment / detachment direction DE, and the key receiving portion 22 has a concave portion into which the convex portion is inserted. In the circumferential direction, the position where the convex portion and the concave portion engage is the position where the drive wire W engages with the corresponding insertion hole 25a and the corresponding connecting portion 21c. Note that the key shaft 15 can be disposed on either the base unit 200 or the catheter unit 100, and the key receiving portion 22 can be disposed on the other. For example, the key shaft 15 may be disposed on the base unit 200 side and the key receiving portion 22 may be disposed on the catheter unit 100 side.

[0049] <Connection between motor and drive wire> Using FIG. 6, the connection of the wire drive unit 300, the connection device 21, and the bending drive unit 13 will be described. FIG. 6 is an explanatory diagram of the wire drive unit 300, the connection device 21, and the bending drive unit 13. FIG. 6(a) is a perspective view of the drive source M, the connection portion 21c, and the drive wire W. FIG. 6(b) is an enlarged view of the connection portion 21c and the drive wire W. FIG. 6(c) is a perspective view showing the connection of the wire drive unit 300, the connection device 21, and the bending drive unit 13.

[0050] In this embodiment, the configuration in which each of the first to ninth drive wires (W11 to W33) is connected to each of the first to ninth connection portions (21c11 to 21c33) is the same. Also, the configuration in which each of the first to ninth connection portions (21c11 to 21c33) is connected to each of the first to ninth drive sources (M11 to M33) is the same. Therefore, in the following description, the configuration in which one drive wire W, one connection portion 21c, and one drive source M are connected will be described.

[0051] As shown in FIG. 6(a), the drive source M has an output shaft Ma that is a motor shaft, and a motor body Mb that rotates the output shaft Ma in the rotation direction Rm. A spiral groove is provided on the surface of the output shaft Ma. The output shaft Ma has a so-called screw shape. The motor body Mb is fixed to the motor frame 200b.

[0052] The connection portion 21c has a tractor 21ct connected to the output shaft Ma, and a tractor support shaft 21cs that supports the tractor 21ct. The tractor support shaft 21cs is connected to the connection base 21cb. The connecting portion 21c has a leaf spring 21ch as a holding portion for holding the held portion Wa of the drive wire W. The drive wire W is engaged with the connecting portion 21c through the insertion hole 25a. More specifically, the held portion Wa is engaged with the leaf spring 21ch. As will be described later, the leaf spring 21ch can take a state of sandwiching and fixing the held portion Wa (fixed state) and a state of releasing the held portion Wa (released state).

[0053] The connecting portion 21c has a pressing member 21cp. As also shown in FIG. 6(b), the pressing member 21cp has a gear portion 21cg that meshes with an internal gear 29 described later, and a cam 21cc as a pressing portion for pressing the leaf spring 21ch. As will be described later, the cam 21cc can move relative to the leaf spring 21ch. When the cam 21cc moves, the fixed state and the released state of the leaf spring 21ch are switched.

[0054] The connecting portion 21c is supported by a first bearing B1, a second bearing B2, and a third bearing B3. The first bearing B1 is supported by the first bearing frame 200c of the base unit 200. The second bearing B2 is supported by the second bearing frame 200d of the base unit 200. The third bearing B3 is supported by the third bearing frame 200e of the base unit 200. Therefore, when the output shaft Ma rotates in the rotational direction Rm, the rotation of the connecting portion 21c around the output shaft Ma is restricted. Note that the first bearing B1, the second bearing B2, and the third bearing B3 are provided for each of the first to ninth connecting portions (21c11 to 21c33).

[0055] Since the rotation of the connecting portion 21c around the output shaft Ma is restricted, when the output shaft Ma rotates, a force along the rotational axis direction of the output shaft Ma acts on the tractor 21ct by the spiral groove of the output shaft Ma. As a result, the connecting portion 21c moves along the rotational axis direction of the output shaft Ma (in the Dc direction). When the connecting portion 21c moves, the drive wire W moves and the bending portion 12 bends. That is, the output shaft Ma and the tractor 21ct constitute a so-called feed screw that converts the rotational motion transmitted from the drive source M into linear motion by a screw. In this embodiment, the output shaft Ma and the tractor 21ct are a sliding screw, but they may also be a ball screw.

[0056] As shown in FIG. 6(c), by attaching the catheter unit 100 to the base unit 200, each of the first to ninth drive wires (W11 to W33) and each of the first to ninth connecting portions (21c11 to 21c33) are connected.

[0057] The control unit 3 can independently control each of the first to ninth drive sources (M11 to M33). That is, any of the first to ninth drive sources (M11 to M33) can operate or stop independently regardless of whether the other drive sources are stopped. In other words, the control unit 3 can independently control each of the first to ninth drive wires (W11 to W33). As a result, each of the first to third guide rings (J1 to J3) is independently controlled, and the bending region 12b of the bending portion 12 can be bent in any direction.

[0058] <Mounting of the Catheter Unit> The operation of mounting the catheter unit 100 on the base unit 200 will be described with reference to FIG. 7. FIG. 7 is an explanatory diagram of the mounting of the catheter unit 100. FIG. 7(a) is a view before the catheter unit 100 is mounted on the base unit 200. FIG. 7(b) is a view after the catheter unit 100 is mounted on the base unit 200.

[0059] In this embodiment, the attachment / detachment direction DE of the catheter unit 100 is the same as the direction of the rotation axis 400r of the operation unit 400. Among the attachment / detachment direction DE, the direction in which the catheter unit 100 is attached to the base unit 200 is called the attachment direction Da. Among the attachment / detachment direction DE, the direction in which the catheter unit 100 is removed from the base unit 200 (the opposite direction of the attachment direction Da) is called the removal direction Dd.

[0060] As shown in FIG. 7(a), in the state before the catheter unit 100 is attached to the base unit 200, the wire cover 14 is in the cover position. At this time, the wire cover 14 covers the first to ninth drive wires (W11 to W33) so that the first to ninth held portions (Wa11 to Wa33) do not protrude from the first to ninth wire cover holes (14a11 to 14a33) of the wire cover 14.

[0061] When the key shaft 15 and the key receiving portion 22 are engaged and the catheter unit 100 is moved in the mounting direction Da with respect to the base unit 200, the catheter unit 100 is attached to the base unit 200. By attaching the catheter unit 100 to the base unit 200, the wire cover 14 moves to the retracted position. In this embodiment, the wire cover 14 moves from the cover position to the retracted position by abutting against the base frame 25 (see FIG. 7(b)). More specifically, when attaching the catheter unit 100, the wire cover 14 abuts against the base frame 25 and stops. In this state, by moving the catheter unit 100 in the mounting direction Da, in the catheter unit 100, the wire cover 14 moves relative to the portion other than the wire cover 14. As a result, the wire cover 14 moves from the cover position to the retracted position.

[0062] While the wire cover 14 moves from the cover position to the retracted position, the held portion Wa of the drive wire W protrudes from the wire cover hole 14a of the wire cover 14 and is inserted into the insertion hole 25a. Then, the held portion Wa engages with the leaf spring 21ch of the connecting portion 21c (see FIG. 6(b)).

[0063] In a state where the catheter unit 100 is merely attached to the base unit 200, the catheter unit 100 can be moved in the removal direction Dd with respect to the base unit 200 to remove the catheter unit 100. Also, as will be described later, in a state where the catheter unit 100 is merely attached to the base unit 200, the fixing of the drive wire W and the connecting portion 21c is released. When the operating unit 400 is operated in a state where the catheter unit 100 is attached to the base unit 200, removal of the catheter unit 100 from the base unit 200 is prevented. Further, when the operating unit 400 is operated in a state where the catheter unit 100 is attached to the base unit 200, the bending drive unit 13 is fixed to the connecting device 21, and the bending drive unit 13 is connected to the wire drive unit 300 via the connecting device 21.

[0064] <Fixing and Release of Bending Drive Unit> Using FIGS. 8, 9, 10, 11, 12, 13, and 14, the configuration for fixing the bending drive unit 13 to the connecting device 21 and the configuration for releasing the fixing of the bending drive unit 13 by the connecting device 21 will be described. FIG. 8 is a diagram for explaining the connection between the catheter unit 100 and the base unit 200. FIG. 8(a) is a cross-sectional view of the catheter unit 100 and the base unit 200. FIG. 8(a) is a cross-sectional view obtained by cutting the catheter unit 100 and the base unit 200 along the rotation axis 400r. FIG. 8(b) is a cross-sectional view of the base unit 200. The base unit 200 is a cross-sectional view cut in a direction orthogonal to the rotation axis 400r at the portion of the connecting portion 21c. FIG. 9 is an exploded view for explaining the connection between the catheter unit 100 and the base unit 200. FIGS. 10, 11, 12, 13, and 14 are diagrams for explaining the fixing of the drive wire W by the connecting portion 21c.

[0065] As shown in FIGS. 8(a) and 9, the base unit 200 has a joint (intermediate member, second transmission member) 28 and an internal gear 29 as a moving gear (interlocking gear, transmission member, first transmission member) that interlocks with the operation unit 400 via the joint 28. The joint 28 has a plurality of transmission parts 28c, and the internal gear 29 has a plurality of parts to be transmitted 29c. The plurality of transmission parts 28c are engaged with the plurality of parts to be transmitted 29c. When the joint 28 rotates, the rotation of the joint 28 is transmitted to the internal gear 29.

[0066] When the catheter unit 100 is attached to the base unit 200, an engaging part 400j provided in the operation unit 400 engages with a joint engaging part 28j of the joint 28. When the operation unit 400 rotates, the rotation of the operation unit 400 is transmitted to the joint 28. The operation unit 400, the joint 28, and the internal gear 29 rotate in the same direction. The internal gear 29 has a plurality of tooth parts for switching between a state where each of the first to ninth connecting parts (21c11 to 21c33) fixes each of the first to ninth drive wires (W11 to W33) and a state where each of the first to ninth drive wires (W11 to W33) is released. Each of the plurality of tooth parts (acting part, switching gear part) of the internal gear 29 engages with a gear part 21cg of a pressing member 21cp that each of the first to ninth connecting parts (21c11 to 21c33) has.

[0067] Specifically, in this embodiment, the internal gear 29 includes a first tooth part 29g11, a second tooth part 29g12, a third tooth part 29g13, a fourth tooth part 29g21, a fifth tooth part 29g22, a sixth tooth part 29g23, a seventh tooth part 29g31, an eighth tooth part 29g32, and a ninth tooth part 29g33. Each of the first to ninth tooth parts (29g11 to 29g33) is formed with a gap therebetween. The first tooth portion 29g11 meshes with the gear portion 21cg of the first connecting portion 21c11. The second tooth portion 29g12 meshes with the gear portion 21cg of the second connecting portion 21c12. The third tooth portion 29g13 meshes with the gear portion 21cg of the third connecting portion 21c13. The fourth tooth portion 29g21 meshes with the gear portion 21cg of the fourth connecting portion 21c21. The fifth tooth portion 29g22 meshes with the gear portion 21cg of the fifth connecting portion 21c22. The sixth tooth portion 29g23 meshes with the gear portion 21cg of the sixth connecting portion 21c23. The seventh tooth portion 29g31 meshes with the gear portion 21cg of the seventh connecting portion 21c31. The eighth tooth portion 29g32 meshes with the gear portion 21cg of the eighth connecting portion 21c32. The ninth tooth portion 29g33 meshes with the gear portion 21cg of the ninth connecting portion 21c33. Any one of the first to ninth tooth portions (29g11 to 29g33) can be referred to as the tooth portion 29g. In this embodiment, each of the first to ninth tooth portions (29g11 to 29g33) has the same configuration.

[0068] In this embodiment, the configuration in which each of the first to ninth drive wires (W11 to W33) is connected to each of the first to ninth connecting portions (21c11 to 21c33) is the same. Also, the configuration in which each of the first to ninth connecting portions (21c11 to 21c33) is connected to each of the first to ninth tooth portions (29g11 to 29g33) is the same. Therefore, in the following description, a configuration in which one drive wire W, one connecting portion 21c, and one tooth portion 29g are connected will be described. In each of the first to ninth connecting portions (21c11 to 21c33), when the gear portion 21cg is moved by the internal gear 29, the pressing member 21cp rotates, and the cam 21cc moves between a pressing position and a retracted position retracted from the pressing position.

[0069] By rotating the operation portion 400, the internal gear 29 rotates. When the internal gear 29 rotates, each of the first to ninth connecting portions (21c11 to 21c33) operates. The operation unit 400 can move between a fixed position (lock position) and a removal position while the catheter unit 100 is attached to the base unit 200. Also, as will be described later, the operation unit 400 can move to a release position while the catheter unit 100 is attached to the base unit 200. In the rotational direction of the operation unit 400, the release position is located between the fixed position and the removal position. When the operation unit 400 is in the removal position, the catheter unit 100 is attached to the base unit 200.

[0070] When the catheter unit 100 is attached to the base unit 200, the drive wire W is not fixed (locked) to the connecting portion 21c. This state is referred to as the released state of the connecting portion 21c. Note that the state in which the drive wire W is fixed (locked) to the connecting portion 21c is referred to as the locked state of the connecting portion 21c.

[0071] The operation of fixing the drive wire W to the connecting portion 21c will be described with reference to FIGS. 10, 11, 12, 13, and 14. After the catheter unit 100 is attached to the base unit 200 and before the operation unit 400 is operated, the catheter unit 100 can be removed from the base unit 200. Hereinafter, the state in which the catheter unit 100 can be removed from the base unit 200 is referred to as the removable state.

[0072] FIG. 10 is a diagram showing the state of the internal gear 29 and the connecting portion 21c in the removable state. FIG. 10 is a diagram showing the internal gear 29 and the connecting portion 21c when the operation unit 400 is in the removal position. The leaf spring 21ch of the connecting portion 21c has a fixed portion 21cha fixed to the connecting base 21cb and a pressed portion 21chb that contacts the cam 21cc of the pressing member 21cp. The leaf spring 21ch has a first portion 21chd1 and a second portion 21chd2. When the catheter unit 100 is attached to the base unit 200, the held portion Wa is inserted between the first portion 21chd1 and the second portion 21chd2. The cam 21cc has a holding surface 21cca and a pressing surface 21ccb. In the radial direction of the rotation radius of the pressing member 21cp, the holding surface 21cca is disposed at a position closer to the rotation center 21cpc of the pressing member 21cp than the pressing surface 21ccb.

[0073] As shown in FIG. 10, in the removable state (the state where the operation unit 400 is at the removal position), the leaf spring 21ch is held at a position where the pressed portion 21chb abuts against the holding surface 21cca. Further, the teeth Za1 of the internal gear 29 and the teeth Zb1 of the gear portion 21cg are stopped with a clearance La generated between them.

[0074] In the rotational direction of the operation unit 400, the direction in which the operation unit 400 moves from the removal position toward the release position and the fixed position is called the lock direction (fixing direction), and the direction in which the operation unit 400 moves from the fixed position toward the release position and the removal position is called the release direction. The operation unit 400 rotates in the release direction from the release position and moves to the removal position. The operation unit 400 rotates in the lock direction from the release position and moves to the fixed position.

[0075] When the catheter unit 100 is attached to the base unit 200 and the operation unit 400 is at the removal position, the connecting portion 21c is in the released state, and the fixing of the drive wire W by the connecting portion 21c is released. When the connecting portion 21c is in the released state, the cam 21cc is located at a retracted position retracted from a pressing position described later. At this time, the fixing of the held portion Wa by the leaf spring 21ch is released. The force with which the first portion 21chd1 and the second portion 21chd2 tighten the held portion Wa when the connecting portion 21c is in the released state is smaller than the force with which the first portion 21chd1 and the second portion 21chd2 tighten the held portion Wa when the connecting portion 21c is in the locked state. When the connecting portion 21c is in the released state, if the catheter unit is moved in the removal direction Dd with respect to the base unit 200, the held portion Wa can be pulled out between the first portion 21chd1 and the second portion 21chd2. When the connecting portion 21c is in the released state, it is preferable that the force for the first portion 21chd1 and the second portion 21chd2 to clamp the held portion Wa does not occur (the state where the magnitude is zero). When the connecting portion 21c is in the released state, it is preferable that a gap is formed between at least one of the first portion 21chd1 and the second portion 21chd2 and the held portion Wa.

[0076] FIG. 11 is a diagram showing the state of the internal gear 29 and the connecting portion 21c when the operation unit 400 is rotated in the locking direction from the removal position. FIG. 11 is a diagram showing the state of the internal gear 29 and the connecting portion 21c in the state where the operation unit 400 is in the release position. When the operation unit 400 is in the removal position (FIG. 10) and the operation unit 400 is rotated in the locking direction, the internal gear 29 rotates clockwise. And the operation unit 400 is located at the release position. Note that even when the operation unit 400 is rotated, since the key shaft 15 and the key receiving portion 22 are engaged, the entire catheter unit 100 (excluding the operation unit 400) is restricted from rotating with respect to the base unit 200. That is, the operation unit 400 can rotate with respect to the entire catheter unit 100 (excluding the operation unit 400) and the base unit 200 in a state where they are stopped.

[0077] When the internal gear 29 rotates clockwise, the clearance between the tooth Za1 of the internal gear 29 and the tooth Zb1 of the gear portion 21cg decreases from the clearance La to the clearance Lb. The tooth Zb2 of the gear portion 21cg is arranged at a position with a clearance Lz from the tooth tip circle (dotted line) of the tooth portion 29g of the internal gear 29. Therefore, the internal gear 29 can rotate without interfering with the tooth Zb2. On the other hand, the connecting portion 21c is maintained in the same state (released state) as the state shown in FIG. 10.

[0078] When the operation unit 400 is further rotated in the locking direction from the state shown in FIG. 11, the internal gear 29 further rotates clockwise. The state of the internal gear 29 and the connecting portion 21c at that time is shown in FIG. 12. FIG. 12 is a diagram showing the state of the internal gear 29 and the connecting portion 21c when the operation unit 400 is rotated from the release position in the locking direction. As shown in FIG. 12, when the operation unit 400 is rotated from the release position in the locking direction, the tooth Za1 of the internal gear 29 contacts the tooth Zb1 of the gear portion 21cg. On the other hand, the connecting portion 21c is in the same state as the state shown in FIGS. 10 and 11 and is kept in the released state.

[0079] FIG. 13 is a diagram showing the state in which the pressing member 21cp is rotated when the operation unit 400 is rotated in the locking direction. As shown in FIG. 13, when the operation unit 400 is further rotated in the locking direction from the state of FIG. 12, the internal gear 29 further rotates clockwise. When the internal gear 29 moves from the state of FIG. 12 to the state of FIG. 13, the internal gear 29 rotates the gear portion 21cg clockwise. When the gear portion 21cg rotates, the holding surface 21cca moves away from the pressed portion 21chb, and the pressing surface 21ccb approaches the pressed portion 21chb. Then, the sandwiching of the held portion Wa by the first portion 21chd1 and the second portion 21chd2 is started.

[0080] Then, while the pressed portion 21chb is pressed by the corner portion 21ccb1 disposed at the end of the pressing surface 21ccb, the tooth Za3 of the internal gear 29 moves to a position away from the tooth Zb3 of the gear portion 21cg. At this time, the held portion Wa is sandwiched by the first portion 21chd1 and the second portion 21chd2. When the tooth Za3 of the internal gear 29 separates from the tooth Zb3 of the gear portion 21cg, the transmission of the driving force from the internal gear 29 to the gear portion 21cg ends. At this time, the cam 21cc is in a state where the corner portion 21ccb1 receives the reaction force from the leaf spring 21ch. In the radial direction of the rotation radius of the pressing member 21cp, the reaction force of the leaf spring 21ch acting on the corner portion 21ccb1 acts at a position away from the rotation center 21cpc of the pressing member 21cp, and the pressing member 21cp rotates clockwise. At this time, the pressing member 21cp rotates in the same direction as the direction in which it is rotated by the internal gear 29 rotating clockwise.

[0081] FIG. 14 is a view showing the state of the internal gear 29 and the connecting portion 21c when the operation unit 400 is in a fixed position. As shown in FIG. 14, from the state shown in FIG. 13, the pressing member 21cp further rotates under the reaction force of the leaf spring 21ch. As shown in FIG. 14, the pressing member 21cp stops in a state where the pressing surface 21ccb of the cam 21cc and the pressed portion 21chb of the leaf spring 21ch are in surface contact. That is, the surfaces of the pressing surface 21ccb and the pressed portion 21chb are arranged on the same plane. At this time, the connecting portion 21c is in a locked state. When the connecting portion 21c is in the locked state, the cam portion 21cc of the pressing member 21cp is located at the pressing position, and the pressing surface 21ccb presses the pressed portion 21chb.

[0082] When the connecting portion 21c is in the locked state, the held portion Wa is sandwiched by the first portion 21chd1 and the second portion 21chd2. That is, the leaf spring 21ch is pressed by the cam 21cc, and the held portion Wa is tightened by the leaf spring 21ch. As a result, the held portion Wa is fixed by the leaf spring 21ch.

[0083] In the present embodiment, the first portion 21chd1 and the second portion 21chd2 of the leaf spring 21ch press the held portion Wa at positions separated from each other. Further, a bent portion 21chc connecting the first portion 21chd1 and the second portion 21chd2 is arranged between the first portion 21chd1 and the second portion 21chd2. The bent portion 21chc is arranged with a gap G from the held portion Wa. By doing so, the held portion Wa can be stably fixed by the first portion 21chd1 and the second portion 21chd2. As the material of the leaf spring 21ch, resin or metal can be used, but it is preferable to use metal. When the connecting portion 21c is in the locked state, pulling out the held portion Wa from between the first portion 21chd1 and the second portion 21chd2 is restricted. Note that the teeth Za3 of the internal gear 29 and the teeth Zb4 of the gear portion 21cg stop at positions where a clearance Lc is generated between them.

[0084] When releasing the fixation between the drive wire W and the connecting portion 21c, the operation portion 400 located at the fixation position is rotated in the release direction. At this time, the internal gear 29 rotates counterclockwise from the state shown in FIG. 14. When the internal gear 29 rotates counterclockwise, the tooth Za3 of the internal gear 29 abuts against the tooth Zb4 of the gear portion 21cg, and the pressing member 21cp is rotated counterclockwise. By further rotating the internal gear 29 counterclockwise, the fixation of the drive wire W by the connecting portion 21c is released. The operations of the internal gear 29 and the pressing member 21cp at this time are opposite to the above-described operations. That is, the fixation of the drive wire W by the connecting portion 21c is released by an operation opposite to the operation when the drive wire W is fixed by the connecting portion 21c described above.

[0085] The above operations are performed for each of the first to ninth connecting portions (21c11 to 21c33). That is, in the process of the operation portion 400 moving from the removal position to the fixation position, the first to ninth connecting portions (21c11 to 21c33) change from the released state to the locked state due to the movement (rotation) of the operation portion 400. In the process of the operation portion 400 moving from the fixation position to the removal position, the first to ninth connecting portions (21c11 to 21c33) change from the locked state to the released state due to the movement (rotation) of the operation portion 400.

[0086] A state in which each of the first to ninth drive wires (W11 to W33) is fixed by each of the first to ninth connecting portions (21c11 to 21c33) is referred to as a first state. A state in which the fixation of each of the first to ninth drive wires (W11 to W33) by each of the first to ninth connecting portions (21c11 to 21c33) is released is referred to as a second state. In conjunction with the movement of the operation portion 400, the first state and the second state are switched. That is, the first state and the second state are switched in conjunction with the movement of the operation portion 400 between the removal position and the fixation position.

[0087] The internal gear 29 is configured to be interlocked with the operation unit 400. In this embodiment, the joint 28 functions as a transmission member for interlocking the operation unit 400 and the internal gear 29. The internal gear 29 and the joint 28 function as an interlocking unit that interlocks with the operation unit 400 such that the first state and the second state are switched in conjunction with the movement of the operation unit 400. Specifically, with the catheter unit 100 attached to the base unit 200, the internal gear 29 and the joint 28 move a part (the pressed portion 21chb) of the leaf spring 21ch relative to the held portion Wa in conjunction with the movement of the operation unit 400. By moving the pressed portion 21chb, the locked state and the released state of the connecting portion 21c are switched. Note that the internal gear 29 may be configured to be directly moved from the operation unit 400. In that case, the internal gear 29 functions as an interlocking unit.

[0088] <Movement of the operation unit> The movement of the operation unit 400 will be described with reference to FIGS. 15, 16, and 17. In this embodiment, with the catheter unit 100 attached to the base unit 200, the operation unit 400 is configured to be movable between a removal position, a release position, and a fixed position. The release position is located between the removal position and the fixed position. In this embodiment, the first state and the second state are switched in conjunction with the movement of the operation unit 400 between the release position and the fixed position. In this embodiment, the operation unit 400 is movable between the removal position and the fixed position by moving in a direction different from the attachment / detachment direction DE. The operation unit 400 moves in a direction (preferably orthogonal) intersecting the attachment / detachment direction DE to move between the removal position and the fixed position. In this embodiment, the operation unit 400 rotates around the rotation axis 400r extending in the attachment / detachment direction DE to move between the removal position and the fixed position.

[0089] FIG. 15 is an explanatory diagram of the catheter unit 100 and the base unit 200. FIG. 15(a) is a cross-sectional view of the catheter unit 100. FIG. 15(b) is a perspective view of the button 41. FIG. 15(c) is a perspective view of the base unit 200. FIG. 16 is a diagram for explaining the operation of the operation unit 400. FIG. 16(a) is a diagram showing the state where the operation unit 400 is in the removal position. FIG. 16(b) is a diagram showing the state where the operation unit 400 is in the release position. FIG. 16(c) is a diagram showing the state where the operation unit 400 is in the fixed position. FIG. 17 is a cross-sectional view for explaining the operation of the operation unit 400. FIG. 17(a) is a cross-sectional view showing the state where the operation unit 400 is in the removal position. FIG. 17(b) is a cross-sectional view showing the state where the operation unit 400 is in the release position. FIG. 17(c) is a cross-sectional view showing the state where the operation unit 400 is in the fixed position.

[0090] When the operation unit 400 is in the fixed position, the connecting portion 21c is in a locked state, and the held portion Wa of the drive wire W is fixed to the corresponding connecting portion 21c (see FIG. 14). When the operation unit 400 is in the release position, the connecting portion 21c is in a released state, and the lock between the held portion Wa of the drive wire W and the connecting portion 21c is released (see FIG. 11). In this state, the connection between the drive wire W and the wire drive unit 300 is disconnected. Therefore, when the catheter 11 receives an external force, the bending portion 12 can be freely bent without receiving resistance from the wire drive unit 300.

[0091] When the operation unit 400 is in the removal position, it is permitted to remove the catheter unit 100 from the base unit 200. Also, with the operation unit 400 in the removal position, the catheter unit 100 can be attached to the base unit 200. When the operation unit 400 is in the removal position, the connecting portion 21c is in a released state, and the lock between the held portion Wa of the drive wire W and the connecting portion 21c is released (see FIG. 10). As shown in FIG. 15(a), the catheter unit 100 includes an operation unit biasing spring 43 that biases the operation unit 400, a button 41 as a moving member, and a button spring 42 that biases the button 41.

[0092] In this embodiment, the operation unit biasing spring 43 is a compression spring. The operation unit 400 is biased by the operation unit biasing spring 43 in a direction Dh approaching the proximal end cover 16. In this embodiment, the button 41 and the button spring 42 are provided in the operation unit 400. When the operation unit 400 moves to the removal position, the release position, or the fixed position, the button 41 and the button spring 42 move together with the operation unit 400. The button 41 is configured to be movable relative to the operation unit 400 in a direction intersecting the direction of the rotation axis 400r of the operation unit 400. The button 41 is biased by the button spring 42 toward the outside of the catheter unit 100 (in a direction away from the rotation axis 400r).

[0093] As will be described later, the movement of the operation unit 400 from the release position to the removal position is restricted by the button 41. Also, by moving the button 41 relative to the operation unit 400, the operation unit 400 is allowed to move from the release position to the removal position. The button 41 has a button protrusion (regulated portion) 41a. The button protrusion 41a has a button slope 41a1 and a regulated surface 41a2.

[0094] The base unit 200 includes a base frame 25. The base frame 25 is provided with a lock shaft 26. The lock shaft 26 is provided with a lock protrusion (regulation portion) 26a. In this embodiment, a plurality (two in this embodiment) of lock shafts 26 are provided. All of the lock shafts 26 may be provided with lock protrusions 26a, or some of the lock shafts 26 may be provided with lock protrusions 26a.

[0095] On one hand, as shown in FIGS. 9, 16(a), 16(b), and 16(c), inside the operation unit 400, a locking groove 400a that engages with the locking shaft 26 is provided. The locking groove 400a extends in a direction different from the attachment / detachment direction DE. In this embodiment, it extends in the rotational direction of the operation unit 400. It can also be said that the locking groove 400a extends in a direction (orthogonal direction) intersecting the attachment / detachment direction DE. When a plurality of locking shafts 26 are provided, the locking groove 400a is provided for each of the plurality of locking shafts 26.

[0096] As shown in FIG. 16(a), when the catheter unit 100 is attached to the base unit 200, the locking shaft 26 engages with the locking groove 400a through the entrance 400a1 of the locking groove 400a. At this time, the operation unit 400 is located at the removal position, and the connecting portion 21c is in the released state (see FIG. 10). Therefore, the fixing of each of the first to ninth drive wires (W11 to W33) by each of the first to ninth connecting portions (21c11 to 21c33) is released. Also, as shown in FIG. 17(a), the button projection 41a and the locking projection 26a face each other.

[0097] With the operation unit 400 in the removal position, when the operation unit 400 is rotated in the locking direction R1, the slope 41a1 of the button projection 41a abuts against the slope 26a1 of the locking projection 26a. Against the biasing force of the button spring 42, the button 41 moves toward the inside of the operation unit 400 (in the direction approaching the rotation axis 400r). Then, the button projection 41a gets over the locking projection 26a, and the operation unit 400 moves to the release position (see FIG. 17(b)). At this time, the connecting portion 21c is in the released state (see FIG. 11). Therefore, the fixing of each of the first to ninth drive wires (W11 to W33) by each of the first to ninth connecting portions (21c11 to 21c33) is released.

[0098] When the operation unit 400 is in the released position and the operation unit 400 is rotated in the locking direction R1, the operation unit 400 moves to the fixed position. As shown in FIG. 17(c), when the operation unit 400 is in the fixed position, the positioning portion 400a2 of the lock groove 400a is located at a position corresponding to the lock shaft 26. The operation unit 400 is biased by the operation unit biasing spring 43 in a direction Dh approaching the proximal end cover 16. As a result, the positioning portion 400a2 engages with the lock shaft 26. In the process of the operation unit 400 moving from the released position to the fixed position, as described above, the held portion Wa of the drive wire W is fixed to the connecting portion 21c.

[0099] When the operation unit is in the fixed position, the connecting portion 21c is in a locked state (see FIG. 14). Therefore, each of the first to ninth drive wires (W11 to W33) is fixed to each of the first to ninth connecting portions (21c11 to 21c33). In this state, the driving force from the wire driving unit 300 can be transmitted to the bending driving unit 13. That is, the driving force from each of the first to ninth drive sources (M11 to M33) can be transmitted to each of the first to ninth drive wires (W11 to W33) via the first to ninth connecting portions (21c11 to 21c33).

[0100] When the operation unit 400 is in the released position, in the removal direction Dd of the catheter unit 100, the wall 400a3 forming the lock groove 400a is located upstream of the lock shaft 26. When the operation unit 400 is in the fixed position, in the removal direction Dd, the positioning portion 400a2 is located upstream of the lock shaft 26. As a result, when the operation unit 400 is in the released position and when it is in the fixed position, removing the catheter unit 100 from the base unit 200 is restricted. On the other hand, when the operation unit 400 is in the removal position, in the removal direction Dd, the entrance 400a1 of the lock groove 400a is located upstream of the lock shaft 26. As a result, removing the catheter unit 100 from the base unit 200 is permitted.

[0101] When the operation unit 400 rotates in the release direction R2 with the operation unit 400 in the fixed position, the operation unit 400 is positioned at the release position. In the process of the operation unit 400 moving from the fixed position to the release position, as described above, the held portion Wa of the drive wire W is released from the connecting portion 21c.

[0102] In a state where the operation unit 400 is positioned at the release position, the regulated surface 41a2 of the button protrusion 41a abuts on the regulating surface 26a2 of the lock protrusion 26 (see Fig. 17(b)). In this state, rotating the operation unit 400 in the release direction R2 is restricted. Also, removing the catheter unit 100 from the base unit 200 is restricted.

[0103] In a state where the operation unit 400 is positioned at the release position, when the user pushes the button 41 inwardly toward the operation unit 400, the regulated surface 41a2 separates from the regulating surface 26a2, and the button protrusion 41a gets over the lock protrusion 26a. As a result, the operation unit 400 is allowed to rotate in the release direction R2, and the operation unit 400 can move from the release position to the removal position.

[0104] When the operation unit 400 is positioned at the removal position, the connecting portion 21c is in the released state. In this embodiment, the number of the lock protrusion 26a and the button 41 is one each. However, the medical device 1 may have a plurality of the lock protrusion 26a and the button 41.

[0105] <Layout of the driving force transmission mechanism> Hereinafter, the layout of the driving force transmission mechanism for transmitting the driving force of the drive source M to the drive wire W will be described. FIG. 18 is a cross-sectional view for explaining the layout of the driving force transmission mechanism. FIG. 18 is a cross-sectional view taken along the rotation axis 400r in a state where the catheter unit 100 and the base unit 200 are connected. In FIG. 18, one of the first to ninth driving wires (W11 to W33) having the same shape, the wire driving unit 300 for driving the one driving wire W, and a part of the connection device 21 and the bending driving unit 13 are extracted and shown. Further, FIG. 19 is an enlarged cross-sectional view for explaining the layout of the driving force transmission mechanism, (a) is an enlarged view on the catheter unit 100 side, and (b) is an enlarged view on the base unit 200 side.

[0106] In the layout of the driving force transmission mechanism of this embodiment, the held portion W at the end of the driving wire W, the tractor support shaft 21cs, and the output shaft Ma of the driving source M are arranged as follows. The held portion W, the tractor support shaft 21cs, and the output shaft Ma each extend in the axial direction of the pitch circle, that is, are arranged parallel to each other. And the tractor support shaft 21cs is arranged at a position offset to the outside in the radial direction of the pitch circle with respect to the held portion W. Further, the output shaft Ma is arranged at a position offset to the outside in the radial direction of the pitch circle with respect to the tractor support shaft 21cs. That is, there is a pitch circle (referred to as the first pitch circle) where the driving wire W is provided, and a pitch circle (referred to as the second pitch circle) where the output shaft Ma is provided, which is offset to the outside of the first pitch circle. And the tractor support shaft 21cs is provided along a pitch circle (referred to as the third pitch circle) that is offset to the outside of the first pitch circle and offset to the inside of the second pitch circle. In this way, in the direction from the catheter 11 toward the driving source M, the layout is such that the tractor support shaft 21cs is sequentially offset to the outside with respect to the held portion W, and the output shaft Ma is offset to the outside with respect to the tractor support shaft 21cs.

[0107] One end of the drive wire W is fixed to any one of the first to third guide rings (J1 to J3) described with reference to FIG. 3(b). The catheter 11 is assumed to be inserted into a patient's body. A plurality of drive wires W at the distal end of the catheter are arranged in a layout such that the diameter of the first pitch circle on which they are arranged is minimized as much as possible, so that access can be made to even finer parts. On the other hand, on the base unit 200 side, due to size constraints of components constituting the connecting portion 21c that connects the drive wire W to the drive source M, etc., the diameter of the first pitch circle is increased. Therefore, a bending guide 45 for guiding the drive wire W so that the first pitch circle becomes larger is installed inside the proximal end cover 16 that covers a part of the drive wire W.

[0108] The drive wire W guided by the bending guide 45 has a held portion Wa corresponding to the other end that is not the side fixed by the guide rings (J1 to J3), and is fixed to the connection base 21cb and the leaf spring 21ch, thereby being connected to one end of a tractor support shaft 21cs that is an intermediate support shaft. In this embodiment, these connection base 21cb and leaf spring 21ch correspond to a first connection member that connects the end of the drive wire W and the tractor support shaft 21cs. Further, one end of the tractor support shaft 21cs, which is connected to the drive wire W, has the other end connected to the output shaft Ma of the drive source M via a tractor 21ct. In this embodiment, the tractor 21ct corresponds to a second connection member that connects the tractor support shaft 21cs and the output shaft Ma, and converts the rotation of the output shaft Ma into a linear motion to linearly move the tractor support shaft 21cs.

[0109] Here, the action of the driving force generated by the drive source M on the drive wire W will be described. As shown in Fig. 19(a), the bending guide 45 is a fixed pipe-shaped member, and the drive wire W is configured to be movable inside it. Inside the bending guide 45, the drive wire W is guided so as to be bent at two locations: the first bending portion 45c1 on the catheter 11 side and the second bending portion 45c2 on the drive source M side. Let the axial distance of the pitch circle between the first bending portion 45c1 and the second bending portion 45c2 be Lax. Receiving power from the drive source M, the drive wire W moves in the Dc direction. Among the Dc directions, the direction in which the drive wire W advances is called the Dcf direction, and the direction in which it retreats is called the Dcb direction.

[0110] In this state, when the drive wire W is moved in the Dcf direction, with respect to the pushing force F generated by the drive source M, a moment is generated with the first bending portion 45c1 as the fulcrum and the difference Lr between the radii before and after the change of the pitch circle formed by the drive wire W before and after bending as the length of the arm. Due to this moment, a force acts to bend the drive wire W more. Also, when the drive wire W is moved in the Dcf direction or the Dcb direction, since the posture of the drive wire W is restricted, frictional forces in the direction of preventing the movement of the drive wire W are generated by actively contacting the surroundings of the first bending portion 45c1 and the second bending portion 45c2.

[0111] The magnitudes of these forces are in a relationship where they increase as the distance Lr increases and as the distance Lax decreases. This becomes a loss in the transmission of the driving force to the drive wire W and a factor that inhibits the smooth movement of the drive wire W. Therefore, when guiding the drive wire W to the outside in the radial direction of the pitch circle, it is desirable that the distance Lr be minimized and the distance Lax be maximized. However, increasing the distance Lax is accompanied by an extension of the drive wire W and an increase in the size of the device, which may cause other adverse effects. Therefore, it may be set to satisfy at least Lr < Lax.

[0112] Also, as shown in Fig. 19(b), the tractor support shaft 21cs is in a positional relationship separated by a distance Lt from the output shaft Ma of the drive source M in the radial direction of the pitch circle via the tractor 21ct. As described above, the tractor 21ct converts the rotational motion transmitted from the output shaft Ma of the drive source M into the linear motion of the tractor support shaft 21cs by the screw portion St. The tractor support shaft 21cs is restricted from moving in directions other than the Dc direction in which the drive wire W moves by the first bearing B1 and the second bearing B2. The tractor 21ct that moves integrally with the tractor support shaft 21cs receives the action of the moment Mt with the fixed portion ft with the tractor support shaft 21cs as a fulcrum due to the straight-ahead force generated by the rotation of the output shaft Ma via the screw portion St. The magnitude of this moment Mt is in a proportional relationship with the distance Lt, and the larger the moment Mt, the larger the radial load received by the bearings B1 and B2 that support the tractor support shaft 21cs. Therefore, the sliding resistance during the movement of the tractor support shaft 21cs in the thrust direction increases, and as a result, it may become a factor that inhibits the smooth movement of the drive wire W. Also, from the viewpoints of wear of the bearings B1 and B2, increase in the load torque of the drive source M, and wear due to the frictional force generated in the screw portion St, it is likely to cause the disadvantage of poor durability. Therefore, it is desirable to set the distance Lt as small as possible.

[0113] As also shown in FIG. 19(b), in the medical device 1 in this embodiment, regarding the cross-sectional area orthogonal to the extending direction of the catheter 11, the size of the region for housing the motor body Mb is the largest. Generally, the output torque required for the motor is restricted according to the specifications of the device, and it is not uncommon for the lower limit size of the motor to be the bottleneck of the overall size of the device. This embodiment is no exception, and the position of the output shaft Ma of the motor body Mb is determined by the layout constraints of the motor body Mb.

[0114] In this embodiment, the connecting portion 21c and the drive source M are supported by a frame so as to be disposed at predetermined positions on the circumference in a cross section orthogonal to the extending direction of the catheter 11. Specifically, the motor body Mb of the drive source M is supported by the motor frame 200b, and the connecting portion 21c is supported by the first bearing frame 200c, the second bearing frame 200d, and the third bearing frame 200e. Here, the motor frame 200b has a cylindrical portion 200bs, and the third bearing frame 200e, which is the closest to the catheter 11 among the frames 200b to 200e, is connected to the outer periphery of the end of the cylindrical portion 200bs. The cylindrical portion 200bs is disposed so as to pass through the space at the center of the circle generated when the connecting device 21 is laid out on the circumference in a cross section orthogonal to the extending direction of the catheter 11. In this way, the motor frame 200b and the third bearing frame 200e are connected via the cylindrical portion 200bs, which is a support portion connecting portion disposed inside the connecting portion 21c. Further, the first bearing frame 200c and the second bearing frame 200d are supported by the motor frame 200b. In this way, the first bearing frame 200c, the second bearing frame 200d, and the third bearing frame 200e are positioned with respect to the motor frame 200b. Further, the catheter unit 100 has a key shaft 15 that is a positioning shaft. The key shaft 15 is disposed at the center of the circle in a cross section orthogonal to the extending direction of the catheter 11. In this way, the key shaft 15 is disposed inside the connecting portion 21c, inserted into the cylindrical portion 200bs of the motor frame 200b, and connected to the cylindrical portion 200bs. By disposing the cylindrical portion 200bs of the motor frame 200b inside the connecting portion 21c as described above, it is possible to secure the degree of freedom in arranging the driving force transmission mechanism while suppressing the increase in the size of the entire device. In this embodiment, the motor frame 200b corresponds to the first support member in the present invention, and the third bearing frame 200e corresponds to the second support member in the present invention.

[0115] As described above, there are a first pitch circle where the drive wire W is provided and a second pitch circle where the output shaft Ma is provided, which is offset outward from the first pitch circle. The tractor support shaft 21cs is provided along a third pitch circle that is offset outward from the first pitch circle and inward from the second pitch circle. With such a layout of the drive force transmission mechanism, the axial distance Lt between the output shaft Ma and the tractor support shaft 21cs can be reduced, and the moment Mt applied to the tractor 21ct during driving can be reduced. As a result, the resistance acting on the tractor support shaft 21cs can be suppressed, and the wear between the output shaft Ma and the threaded portion St of the tractor 21ct can be reduced. Also, the difference Lr in the radius before and after the change in the pitch circle formed by the drive wire W before and after bending can be reduced, reducing the moment that tries to bend the drive wire W more during driving and suppressing the generation of frictional force in the direction that hinders the movement of the drive wire W. Thereby, the loss of drive force transmission to the drive wire W can be reduced. Therefore, it is possible to provide a continuum robot that improves durability and realizes smooth movement of the drive wire W.

[0116] In this embodiment, the catheter unit 100 is configured to be detachable from the base unit 200. Specifically, it has the configuration described with reference to FIGS. 15 to 17 so that the user can easily replace the catheter unit 100. As described above, the leaf spring 21ch as the holding part and the held part W can be switched between the fixed state and the released state, and are configured to be detachable. Then, the interlocking parts (joint 28, internal gear 29) interlocking with the movement of the operation unit 400 switch between the fixed state and the released state. In this configuration, the interlocking parts are arranged outside a predetermined part of the connecting part 21c. In this embodiment, they are arranged outside the part on the catheter 11 side with respect to the output shaft Ma (see FIG. 8(a)). Thereby, the interlocking parts are arranged using the space outside the first connecting member or the tractor support shaft 21cs arranged at a position offset radially inward of the pitch circle with respect to the output shaft Ma, and the size increase of the entire device can be suppressed. Also, the interlocking parts can be arranged near the operation unit 400, and the force required for the operation of the operation unit 400 can be reduced.

[0117] Note that the effects of the present invention can be enjoyed regardless of whether the catheter unit 100 is detachable from the base unit 200. That is, even in a configuration where the replacement of the catheter 11 is not required or simple replacement by the user is not required without the configuration described with reference to FIGS. 15 to 17, by adopting the layout of the driving force transmission mechanism shown in FIGS. 18 and 19, the durability can be improved and smooth movement of the drive wire W can be realized.

[0118] As described above, the present invention has been described together with the embodiments. However, the above embodiments are merely examples of the concretization in implementing the present invention, and the technical scope of the present invention should not be construed in a limited manner by these. That is, the present invention can be implemented in various forms without departing from its technical idea or its main features.

Explanation of Reference Numerals

[0119] 100: Catheter unit, 200: Base unit, 11: Catheter, 21: Connecting device, 21c: Connecting part, 21cb: Connecting base, 21ch: Leaf spring, 21cs: Tractor support shaft, 21ct: Tractor, 45: Bending guide, 45c1, 45c2: Bending parts, 100: Catheter unit, 200: Base unit, 200b: Motor frame, 200c - 200e: Bearing frame, 200bs: Cylindrical part, 400: Operation part, M: Driving source (motor), Ma: Output shaft, W: Driving wire, Wa: Held part

Claims

1. A continuum robot comprising: a bendable body having a plurality of linear members provided along a first pitch circle; and a plurality of output shafts respectively provided along a second pitch circle offset outward from the first pitch circle, the plurality of motors driving the plurality of linear members to bend the bendable body. A plurality of intermediate support shafts provided along a third pitch circle offset outward from the first pitch circle and offset inward from the second pitch circle. A plurality of first connecting members respectively connecting the ends of the plurality of linear members and the plurality of intermediate support shafts. A plurality of second connecting members respectively connecting the plurality of intermediate support shafts and the plurality of output shafts, and converting the rotation of the output shafts into linear motion to linearly move the intermediate support shafts. The continuum robot is characterized by comprising the above.

2. A first support member for supporting the motor. A second support member for supporting a connecting portion including the intermediate support shaft, the first connecting member, and the second connecting member. The continuum robot according to claim 1, wherein the first support member and the second support member are connected via a support portion connecting portion disposed inside the connecting portion.

3. A positioning shaft disposed inside the connecting portion. The continuum robot according to claim 2, wherein the positioning shaft is connected to the support portion connecting portion.

4. A holding portion of the first connecting member and a held portion of the linear member are switchable between a fixed state and a released state, and are configured to be detachable. It is switched between the fixed state and the released state by an interlocking portion interlocking with the movement of an operation portion. The continuous robot according to any one of claims 1 to 3, wherein the interlocking part is arranged outside a predetermined part of a connecting part including the intermediate support shaft, the first connecting member, and the second connecting member.

5. The continuous robot according to claim 4, wherein the operating part is configured to be rotatable around a rotation axis extending in a direction in which the held part is attached to and detached from the holding part.

6. The continuous robot according to any one of claims 1 to 5, comprising a first bending part and a second bending part that bend the linear member so as to change the diameter of the first pitch circle. The continuous robot according to any one of claims 1 to 5, wherein the difference in radius before and after the change of the pitch circle is smaller than the axial distance of the pitch circle between the first bending part and the second bending part.

7. The continuous robot according to claim 6, comprising a pipe-shaped bending guide including the first bending part and the second bending part, and the linear member is configured to be movable inside the bending guide.

Images