阅读说明：本技术 手术工具 (Surgical tool ) 是由 新藤广树 于 2020-03-10 设计创作，主要内容包括：一种手术工具,其设置有被驱动部、索状体、以及旋转体。驱动力从外部传递给被驱动部。索状体传递被驱动部的移动。旋转体具有圆周面,并且从被驱动部延的索状体缠绕在圆周面上。在圆周面上设置有多个槽以及至少一个切口部,多个槽在旋转体的中心轴线方向上并排设置,并且能够供索状体缠绕,至少一个切口部连接多个槽中的相邻的槽,并且索状体能够以经由至少一个切口部而跨越相邻的槽的方式配置。(A surgical tool is provided with a driven part, a cord-like body, and a rotating body. The driving force is transmitted from the outside to the driven portion. The cord transmits the movement of the driven portion. The rotating body has a circumferential surface, and the cord-like body extending from the driven portion is wound around the circumferential surface. The circumferential surface is provided with a plurality of grooves which are arranged side by side in the direction of the central axis of the rotating body and around which the cord-like body can be wound, and at least one cutout portion which connects adjacent ones of the plurality of grooves and through which the cord-like body can be arranged so as to straddle the adjacent grooves.)

1. A surgical tool, characterized by being provided with:

a driven portion to which a driving force is transmitted from outside;

a cord-like body that transmits movement of the driven portion; and

a rotating body having a circumferential surface around which the cord-like body extending from the driven portion is wound,

the circumferential surface is provided with a plurality of grooves and at least one notch portion,

the plurality of grooves are arranged side by side in a central axis direction of the rotating body and around which the cord-like body can be wound,

the at least one cutout portion connects adjacent ones of the plurality of grooves, and the cord-like body may be disposed so as to straddle the adjacent ones of the plurality of grooves via the at least one cutout portion.

2. The surgical tool of claim 1,

a protrusion is provided between adjacent ones of the plurality of grooves provided on the circumferential surface,

the at least one cut-out portion is a notch provided at the protrusion.

3. A surgical tool as claimed in claim 1 or 2,

the plurality of grooves are provided with more than three,

the at least one cut-out portion is a plurality of cut-out portions,

the plurality of notches arranged apart in the central axis direction are all provided at the same phase.

4. A surgical tool as claimed in claim 1 or 2,

the plurality of grooves are provided with more than three,

the at least one cut-out portion is a plurality of cut-out portions,

the plurality of notches arranged apart in the central axis direction are provided at different phases, respectively.

Technical Field

The present disclosure relates to surgical tools.

Background

In the master-slave surgical robot, in order to improve safety and shorten the operation learning time of a doctor, the following technique is required: an external force acting on a robot forceps as a surgical tool is transmitted to a surgical operator who operates the robot at the isolation. The external force transmitted to the operator is estimated based on information such as the position and driving force of the actuator.

As a driving method of a surgical tool for driving a robot, a driving method of transmitting a driving force generated by a driving source such as an actuator to the surgical tool via a wire to drive the surgical tool is known. (see, for example, patent document 1.). The wire is arranged between the drive source and the surgical tool, and the tension of the wire is adjusted to be within a predetermined range.

Documents of the prior art

Patent document

Patent document 1: japanese patent No. 4938753

Disclosure of Invention

Problems to be solved by the invention

In the technique described in patent document 1, a part of a wire rod is wound around a cylindrical or cylindrical adjustment member. The tension of the wire is adjusted by adjusting the torque on the adjusting member, which is the force applied in the direction in which the wire is wound.

However, the method of adjusting the tension of the wire by adjusting the torque on the adjusting member is difficult to finely adjust the tension. Further, it is difficult to maintain and fix the adjusted tension.

The tension of the wire is believed to affect the amount of friction that is generated when the driving force is transmitted to the surgical tool. Therefore, when a plurality of wires are provided, the tension of the plurality of wires is different from each other, and therefore variation in tension is likely to occur. That is, the frictional force generated when the surgical tool is driven is different for each wire, and for example, the frictional force generated each time the surgical tool is operated is different for each wire needle. On the contrary, in the external force estimation for transmitting the external force acting on the surgical tool, since the frictional force generated at the time of transmission changes, the accuracy of the external force estimation is also likely to deteriorate.

An aspect of the present disclosure preferably provides a surgical tool that easily improves the accuracy of external force estimation.

Technical scheme for solving problems

The present disclosure provides the following technical solutions.

The surgical tool of the present disclosure is provided with: a driven portion to which a driving force is transmitted from outside; a cord-like body that transmits movement of the driven portion; and a rotating body having a circumferential surface around which the cord-like body extending from the driven portion is wound, the circumferential surface being provided with a plurality of grooves that are provided side by side in a central axis direction of the rotating body and around which the cord-like body can be wound, and at least one cutout portion that connects adjacent grooves among the plurality of grooves, and through which a portion of the cord-like body can be disposed so as to straddle the adjacent grooves.

According to the surgical tool of the present disclosure, even if the phase of the rotating body changes, the movement of the string-like body extending from the rotating body in the central axis direction is easily suppressed, and the tension of the string-like body is easily stabilized, as compared with the case of the rotating body provided with the spiral groove. In other words, it is easy to suppress the variation in the length of the path in which the cord-like body is arranged and to stabilize the tension of the cord-like body.

The frictional force acting on the driven portion region is also easily stabilized, and the accuracy of external force estimation is more easily improved than in the method in which the frictional force acting on the driven portion region is not stabilized. By improving the accuracy of external force estimation in the above manner, a safer operation can be achieved using a surgical tool, and an operation with fewer complications can be achieved. Furthermore, it is easy to improve the QOL (quality of life) of the patient and reduce the burden of the doctor during the operation, and it is helpful to improve the learning curve of the surgical robot.

Compared with a rotating body provided with a spiral groove, the position of the cord-shaped body in the central axis direction when entering the groove and the position of the cord-shaped body in the central axis direction when exiting the groove are easily prevented from being changed due to the phase of the rotating body. Therefore, when winding the cord-like body around the rotating body, it is less necessary to pay attention to the phase of the rotating body. In other words, the operation of winding the cord-like body around the rotating body is facilitated.

In the above disclosure, it is preferable that the circumferential surface is provided with a ridge-shaped protrusion for partitioning the adjacent grooves, and the cutout portion is a notch provided in the protrusion.

In the above disclosure, it is preferable that the groove is provided with three or more, and it is preferable that the plurality of notches arranged separately in the central axis direction are provided at the same phase.

In the above disclosure, it is preferable that the groove is provided in three or more numbers, and the plurality of notches arranged to be separated in the central axis direction are provided in different phases.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the surgical tool of the present disclosure, since the plurality of grooves around which the cord-like bodies can be wound and the cord-like bodies can be disposed so as to span the adjacent grooves via the cut-out portions, the surgical tool can exhibit an effect of easily improving the accuracy of external force estimation in the surgical tool.

Drawings

Fig. 1 is a diagram illustrating a configuration of a surgical tool according to an embodiment of the present disclosure.

Fig. 2 is a partial sectional view illustrating an engagement state with an adapter in the surgical tool of fig. 1.

Fig. 3 is a perspective view illustrating arrangement positions of the first and second housing parts in the surgical tool of fig. 1.

Fig. 4 is a plan view illustrating the structure inside the housing of fig. 1.

Fig. 5 is a partial sectional view illustrating the structure inside the housing of fig. 1.

Fig. 6A is a diagram illustrating a configuration of a groove and a notch provided in a pulley, and fig. 6B is a schematic diagram illustrating a configuration of a wire rod extending from the pulley to an axis.

Fig. 7A is a schematic diagram illustrating movement of the wire in the present embodiment, and fig. 7B is a schematic diagram illustrating movement of the wire in the spiral groove.

Description of reference numerals

1 … surgical tools; 3 … power transmission part (outside); 12 … pliers (action part); 21 … a first shell part (support part); 22 … second housing part (support part); 23 … pulley long holes (long holes); 31 … driving member (driven part); 35 … wire (cord); 41 … pulley (rotator); 46 … pulley rotation shaft (rotation shaft); 49 … front end (convex part); 51 … fixed block (fixed part); 52 … recess; 56 … setscrew (fixing component)

Detailed Description

A surgical tool 1 according to an embodiment of the present disclosure will be described with reference to fig. 1 to 7. The surgical tool 1 of the present embodiment is applied to a master-slave surgical robot. Further, the surgical tool 1 of the present embodiment is used for surgery. As shown in fig. 1, the surgical tool 1 includes a shaft 11 having a forceps 12 disposed at a distal end thereof, and a housing 20 to be attached to the surgical robot. The forceps 12 corresponds to an example of an operation portion.

The shaft 11 is a rod-shaped member extending from the housing 20. In the present embodiment, the shaft 11 is a rod-shaped member extending in the Z-axis direction. The forceps 12 serving as an operating portion is provided at the distal end of the shaft 11, which is the end of the shaft 11 opposite the housing 20. A space extending from the housing 20 toward the forceps 12 is provided inside the shaft 11. In which a wire 35 to be described later can be arranged.

In addition, hereinafter, the end portion of the shaft 11 on the side opposite to the housing 20 is the end portion on the positive side of the Z axis, and the direction from the housing 20 toward the forceps 12 is the positive direction of the Z axis.

As shown in fig. 2, the housing 20 can be attached to the adapter 2 of the surgical robot and detached from the adapter 2. Further, a driving force for driving the forceps 12 is transmitted from the power portion 4 to the housing 20 via the power transmitting portion 3 of the adapter 2. The power transmission unit 3 corresponds to an example of the exterior.

As shown in fig. 3 to 5, the housing 20 includes a first housing portion 21 and a second housing portion 22, a plurality of driving members 31, a wire 35, a plurality of pulleys 41, a plurality of pulley rotation shafts 46, a plurality of fixing blocks 51, and a plurality of fixing screws 56.

The first housing portion 21 and the second housing portion 22 correspond to examples of the first support portion and the second support portion, respectively. The plurality of driving members 31, the wire members 35, the plurality of pulleys 41, the plurality of pulley rotating shafts 46, the plurality of fixing blocks 51, and the plurality of fixing screws 56 correspond to an example of a driven portion, a cord-like body, a rotating shaft portion, a fixing portion, and a fixing member, respectively.

As shown in fig. 4 and 5, the first case portion 21 and the second case portion 22 are plate-like members constituting at least a part of the housing of the case 20. In the present embodiment, the first housing portion 21 is disposed on a surface of the housing 20 facing the adapter 2, and the second housing portion 22 is disposed on a surface of the housing 20 facing the adapter 2. Also, the first and second housing sections 21 and 22 are arranged in parallel to the X-Z plane.

The surface of the housing 20 facing the adapter 2 is a Y-axis negative surface, and the surface of the housing 20 opposite to the adapter 2 is a Y-axis positive surface.

As shown in fig. 4 and 5, at least the wire 35, the plurality of guide pulleys 26, the plurality of pulleys 41, the plurality of pulley rotation shafts 46, and the plurality of fixing blocks 51 are arranged between the first casing section 21 and the second casing section 22.

A plurality of pulley long holes 23 for arranging the plurality of pulleys 41 are provided in a region near an end portion on the opposite side of the shaft 11, that is, a region near an end portion on the Z-axis negative side, of the first casing portion 21 and the second casing portion 22.

The pulley long holes 23 are through holes extending toward the side closer to the shaft 11 in the first case portion 21 and the second case portion 22, that is, toward the Z-axis positive side, respectively. In other words, the pulley long holes 23 are long holes extending in the Z-axis direction. In the present embodiment, the three pulley long holes 23 are arranged in parallel with a space in the X axis direction. The number of the long holes 23 for pulleys is not limited to three, and may be more or less than three.

The first housing portion 21 is provided with a plurality of driving elongated holes 24 for disposing a plurality of driving members 31. The plurality of drive long holes 24 respectively allow the drive member 31 to move in a direction along the first housing portion 21, and restrict the drive member 31 from moving in a direction away from the first housing portion 21, i.e., in the Y-axis direction.

A plurality of long holes 24 for driving are provided in the first housing portion 21 on the shaft 11 side than the long holes 23 for pulleys. For example, in the central region in the Z-axis direction in the first housing portion 21.

Each of the plurality of long drive holes 24 is a through hole linearly extending toward the shaft 11 side, i.e., the Z-axis positive side. In other words, each of the plurality of long drive holes 24 is a long hole extending in the Z-axis direction. In the present embodiment, the three long drive holes 24 are arranged in parallel with a gap in the X-axis direction. The number of long drive holes 24 may be the number corresponding to the number of long pulley holes 23, or may be more or less than three.

In the present embodiment, the three long drive holes 24 are equal in length in the Z-axis direction. The lengths of the three long drive holes 24 in the Z-axis direction may be equal to or different from each other as described above.

The plurality of guide pulleys 26 guide the wire material 35 extending from the plurality of driving members 31 to the shaft 11 into the inner space of the shaft 11. More specifically, the wire 35 extending from the plurality of driving members 31 disposed away from the shaft 11 toward the positive side or the negative side in the X-axis direction is introduced into the shaft 11.

As shown in fig. 4 and 5, a plurality of guide pulleys 26 are disposed between the first and second casing sections 21 and 22 and at an end area on the shaft 11 side, i.e., the Z-axis positive side. In other words, the plurality of guide pulleys 26 are disposed between the long holes 24 for driving and the shaft 11 in the space between the first casing portion 21 and the second casing portion 22.

A plurality of guide pulleys 26 are mounted on at least one of the first and second casing sections 21 and 22, and are rotatable about an axis extending in the Y-axis direction. The shape and configuration of the guide pulley 26 are not particularly limited.

As shown in fig. 4 and 5, the driving force is transmitted from the power transmission portion 3 of the adapter 2 to each of the plurality of driving members 31, and the plurality of driving members 31 transmit the transmitted driving force to the wire 35. The plurality of driving members 31 reciprocate along the long driving holes 24 by the driving force transmitted from the power transmission portion 3.

A concave-convex shape that enables relative movement of each drive member 31 along the first housing portion 21 and restricts movement of each drive member 31 in a direction away from the first housing portion 21 is formed on a surface of each drive member 31 that faces each long drive hole 24. The long drive holes 24 are formed with concave-convex shapes corresponding to the concave-convex shapes of the drive member 31. The shape of the uneven shape is not particularly limited.

Further, in each of the driving members 31, a concave-convex shape for transmitting the driving force is formed in a region opposed to the power transmission portion 3. The concave-convex shape formed on each drive member 31 is also a shape that enables the drive member 31 and the power transmission portion 3 to engage and disengage in the Y-axis direction. The shape of the uneven shape is not particularly limited.

The wire 35 transmits the driving force transmitted to the plurality of driving members 31 to the forceps 12. In other words, the wire 35 transmits the movement of the plurality of driving members 31 to the forceps 12. The material and shape of the wire 35 are not particularly limited.

The wire 35 extending from the plurality of driving members 31 toward the negative direction of the Z axis is wound around the plurality of pulleys 41. After the wire 35 is wound around the plurality of pulleys 41, the wire 35 extends toward the positive direction of the Z axis and is guided to the inside of the shaft 11. Among the end portions of the wire 35, the end portion extending toward the driving member 31 corresponds to an example of a first cord-like body end, and among the end portions of the wire 35, the end portion extending toward the shaft 11 corresponds to an example of a second cord-like body end.

For example, when the plurality of driving members 31 are disposed further to the front side than the shaft 11 in the X-axis direction, the wire material 35 extending from the plurality of driving members 31 in the positive direction of the Z-axis is wound around the plurality of guide pulleys 26 and guided to the inside of the shaft 11.

The wire 35 guided inside the shaft 11 transmits the driving force to the forceps 12. The configuration for transmitting the driving force may be, for example, a configuration in which both end portions of the wire 35 guided inside the shaft 11 are attached to the forceps 12, or a configuration in which both end portions of the wire 35 are connected to each other to form a ring shape and wound around a pulley provided in the forceps 12.

The pulleys 41 are members formed in a cylindrical shape having a circumferential surface around which the wire material 35 is wound, and the pulleys 41 change the direction of the wire material 35 extending from the driving member 31 in the negative direction of the Z axis to the positive direction of the Z axis.

Each of the plurality of pulleys 41 is arranged at the pulley-use long hole 23 with the pulley rotating shaft 46, the fixing block 51, and the fixing screw 56. In other words, each of the plurality of pulleys 41 is arranged at a position: so that the driving member 31 is spaced between the plurality of pulleys 41 and the shaft 11 provided with the forceps 12.

Each of the plurality of pulleys 41 is formed in a cylindrical shape. The length of the pulley 41 formed in a cylindrical shape in the central axis direction is formed smaller than the interval between the first casing section 21 and the second casing section 22. In other words, the height of the pulley 41 formed in a cylindrical shape in the Y-axis direction is formed lower than the interval between the first and second casing sections 21 and 22.

The inner space of the pulley 41 formed in a cylindrical shape is a space for disposing the pulley rotating shaft 46, and a bearing 44 is provided between the pulley 41 and the pulley rotating shaft 46, and the bearing 44 supports the pulley 41 rotatably about the rotation axis L. In addition, the central axis of the pulley 41 coincides with the rotation axis L.

As shown in fig. 6A, three annularly formed grooves 42 are provided in the circumferential surface of the cylindrically formed pulley 41 at equal intervals along the central axis direction of the pulley 41, that is, along the Y-axis direction. In the present embodiment, the width of each of the three grooves 42 is equal to the size when the two wires 35 are arranged in parallel. Further, the width of each of the three grooves 42 may be larger or smaller than the size of the two wires 35 arranged in parallel.

Further, each of the plurality of pulleys 41 is provided with two cutout portions 43 connecting the adjacent plurality of grooves 42. Each of the two cutout portions 43 is formed by cutting off a part of the ridge-like projection defining the adjacent groove 42, and has the following width: the wire 35 can be arranged from one groove 42 to another groove 42. In the present embodiment, the two notch portions 43 are provided side by side in the same phase in the circumferential surface of the pulley 41. The two notches 43 may be arranged side by side at the same phase or at different phases.

As shown in fig. 5, the plurality of pulley rotating shafts 46 are members formed in a cylindrical or columnar shape, rotatably supporting the plurality of pulleys 41. Each of the plurality of pulley rotating shafts 46 includes an insertion portion 47 and an enlarged diameter portion 48, the insertion portion 47 is inserted into the bearing 44 disposed in the internal space of each pulley 41, and the enlarged diameter portion 48 is provided at one end of the insertion portion 47. The front end 49 of the insertion portion 47 is inserted into a recess 52 of a fixing block 51 to be described later. The tip 49 of the insertion portion 47 corresponds to an example of a convex portion.

The diameter-enlarged portion 48 has a shape having a diameter larger than the inner diameter of the bearing 44 through which the insertion portion 47 is inserted. The pulley rotation shafts 46 have the following lengths: in a state where the insertion portion 47 is inserted through the bearing 44 and the diameter-enlarged portion 48 is in contact with the bearing 44, both the end portion of the insertion portion 47 and the end portion of the diameter-enlarged portion 48 protrude from each of the plurality of pulleys 41.

In each of the plurality of pulley rotating shafts 46, a screw hole 50 for screw engagement with a plurality of fixing screws 56 is provided on an end surface on the side of the enlarged diameter portion 48. The plurality of screw holes 50 are provided on the central axis of the plurality of pulley rotating shafts 46 formed in a cylindrical or columnar shape. The plurality of screw holes 50 may be a plurality of holes penetrating the plurality of pulley rotating shafts 46, or may be a plurality of holes having a bottom.

The plurality of fixing blocks 51 are members formed in a cylindrical or columnar shape, and the plurality of fixing blocks 51 support the plurality of pulleys 41 together with the plurality of pulley rotating shafts 46. A recessed portion 52 into which the leading end 49 of the insertion portion 47 is inserted is provided at an end portion of each fixing block 51 on the pulley rotation shaft 46 side, and a screw hole 53 for screw-engagement with a fixing screw 56 is provided at an end portion of each fixing block 51 on the side opposite to the pulley rotation shaft 46 side.

In the present embodiment, the recess 52 is provided in the fixed block 51, and the tip 49 of the insertion portion 47 is inserted into the recess 52, but the following configuration may be adopted: a recess is provided in the insertion portion 47, and a projection provided on the fixing block 51 is inserted into the recess.

The plurality of fixing blocks 51 are disposed between the leading ends 49 of the plurality of pulley rotating shafts 46 and the second housing portion 22, respectively. The plurality of fixing blocks 51 are movable and fixable in the Z-axis direction relative to the second housing section 22. Further, the relative positions between each of the plurality of fixed blocks 51 and the pulley rotation shaft 46 can be changed in the Y-axis direction, and the relative movement between each of the plurality of fixed blocks 51 and the pulley rotation shaft 46 in the X-axis direction and the Z-axis direction is restricted.

As shown in fig. 5, a plurality of fixing screws 56 are inserted into the pulley long holes 23, respectively, and have external threads for screw-engaging with the pulley rotary shaft 46 and the fixing block 51. The fixing screw 56, which is screwed into the screw hole 50 of the pulley rotation shaft 46, sandwiches the first housing portion 21 together with the pulley rotation shaft 46. Further, a fixing screw 56 threadedly engaged with the threaded hole 50 of the pulley rotation shaft 46 presses and fixes the pulley rotation shaft 46 against the first housing portion 21. The fixing screw 56, which is threadedly engaged with the threaded hole 53 of the fixing block 51, sandwiches the second housing portion 22 together with the fixing block 51. The fixing screw 56, which is threadedly engaged with the threaded hole 53 of the fixing block 51, presses and fixes the fixing block 51 against the second housing part 22.

Next, the operation of the surgical tool 1 having the above-described configuration will be described.

As shown in fig. 2, the driving force for driving the forceps 12 of the surgical tool 1 is transmitted from the power section 4 to the plurality of driving members 31 via the power transmitting section 3 of the adapter 2. As shown in fig. 2 and 4, the plurality of driving members 31 reciprocate relative to the housing 20 in the Z-axis direction along the plurality of long driving holes 24.

The movement of each of the plurality of driving members 31 is transmitted to the wire 35. The wire 35 reciprocates in a direction in which it extends. The wire 35 extending from the plurality of driving members 31 toward the forceps 12 side, i.e., toward the positive side in the Z-axis direction reciprocates in a direction guided by the guide pulley 26. The wire 35 extending from the plurality of driving members 31 toward the side where the plurality of pulleys 41 are arranged, that is, toward the negative side in the Z-axis direction reciprocates in the direction guided by the plurality of pulleys 41 and the plurality of guide pulleys 26.

The wire 35 extends in the inner space of the shaft 11 to the forceps 12, and the reciprocating movement of the wire 35 is transmitted to the forceps 12. The forceps 12 are opened and closed by the reciprocating movement of the wire 35. In the present embodiment, the forceps 12 are opened and closed based on the reciprocating movement of the wire 35, but other operations such as a bending operation for changing the direction of the forceps 12 may be performed.

Next, a method of adjusting the tension, i.e., the tension, of the wire 35 will be described with reference to fig. 4 and 5. First, the tension of the wire 35 is adjusted by changing the relative positions of the plurality of pulleys 41 with respect to the housing 20. Specifically, the tension is adjusted by moving the plurality of pulleys 41 in the Z-axis direction along the plurality of pulley long holes 23. For example, the pulling force is increased by moving the plurality of pulleys 41 in a direction away from the axis 11, i.e., in a negative direction of the Z-axis, and the pulling force is weakened by moving the plurality of pulleys 41 in a direction close to the axis 11, i.e., in a positive direction of the Z-axis.

In the case of moving the plurality of pulleys 41 along the plurality of pulley long holes 23, the plurality of fixing screws 56 threadedly engaged with the plurality of pulley rotating shafts 46 are loosened, and the fixing screws 56 threadedly engaged with the fixing block 51 are loosened. In other words, the pressing force of the plurality of pulley rotating shafts 46 against the first casing section 21 is weakened, and the pressing force of the fixing block 51 against the second casing section 22 is weakened.

Thereby, the plurality of pulley rotation shafts 46 and the plurality of fixed blocks 51 can relatively approach each other in the Y-axis direction. Accordingly, a space can be formed between the plurality of pulley rotation shafts 46 and the first housing portion 21, and a space can be formed between the plurality of fixing blocks 51 and the second housing portion 22.

Thereafter, the plurality of pulleys 41 are relatively moved to a position where the tension of the wire 35 reaches a desired value. If the relative positions of the plurality of pulleys 41 are determined, the plurality of fixing screws 56 threadedly engaged with the plurality of pulley rotating shafts 46 are tightened, and the plurality of fixing screws 56 threadedly engaged with the plurality of fixing blocks 51 are tightened. At this time, the plurality of pulley rotation shafts 46 and the plurality of fixed blocks 51 are relatively distant in the Y-axis direction.

In other words, the pressing force of the plurality of pulley rotating shafts 46 against the first casing section 21 increases, and the pressing force of the plurality of fixing blocks 51 against the second casing section 22 increases. Thereby, the frictional force between the plurality of pulley rotating shafts 46 and the first housing portion 21, and the frictional force between the plurality of fixing blocks 51 and the second housing portion 22 are increased. That is, the arrangement positions of the plurality of pulleys 41 are fixed.

Next, winding of the wire 35 around the pulley 41 will be described with reference to fig. 6A to 7B. For example, when the wire rods 35 introduced into the shaft 11 are arranged in the Y-axis direction as shown in fig. 6B, the wire rods 35 are wound around the pulley 41 as shown in fig. 6A.

Specifically, the wire 35 extending from the plurality of driving members 31 or the shaft 11 is wound in the plurality of grooves 42 on the positive side or the negative side in the Y-axis direction of each of the plurality of pulleys 41. The wire 35 wound in the plurality of grooves 42 is guided at the plurality of cutout portions 43 into the plurality of grooves 42 provided in the center of the pulley 41, and is wound in the plurality of grooves 42 in the center. Then, the wire 35 passes through the plurality of cutout portions 43 and is wound in the groove 42 on the Y-axis direction negative side or positive side in the pulley 41, and thereafter extends toward the shaft 11 or the driving member 31.

On the other hand, in the case where the wire rods 35 introduced into the inside of the shaft 11 are arranged in parallel at intervals at the same positions in the Y-axis direction as shown in fig. 6B, the wire rods 35 are wound only in the grooves 42 provided in the center of the pulley 41.

When the wire 35 reciprocates in accordance with the movement of the driving member 31 in the pulley 41 shown in fig. 6A, the pulley 41 also rotates in accordance with the reciprocation of the wire 35 as shown in fig. 7A. Further, the phase of the pulley 41 also changes with the reciprocating movement of the wire 35. At this time, the wire 35 is relatively moved while maintaining the position in the Y-axis direction within a predetermined range.

In other words, since the wire 35 is wound in the groove 42 formed along the X-Z plane, even if the pulley 41 is rotated, it is easy to keep the position in the Y-axis direction when the wire 35 enters the groove 42 or the position in the Y-axis direction when the wire 35 comes out of the groove 42 within a predetermined range. Further, the pulley 41 does not rotate until the position where the wire 35 enters the groove 42 or the position where the wire comes out of the groove 42 overlaps the notch portion 43.

On the other hand, for example, as shown in fig. 7B, when a spiral groove 142 in which the wire material 35 is wound is provided on the circumferential surface of the pulley 141, the position of the wire material 35 in the Y-axis direction fluctuates in accordance with the reciprocating movement of the wire material 35. That is, when the pulley 41 rotates in accordance with the reciprocating movement of the wire 35, the position where the wire 35 enters the spiral groove 142 or the position where the wire exits the spiral groove 142 moves in the Y-axis direction. The position of the wire 35 in the Y-axis direction is changed accordingly.

According to the surgical tool 1 configured as described above, the arrangement positions of the plurality of pulleys 41 with respect to the plurality of driving members 31 and the forceps 12 are adjusted so as to be able to approach or separate from each other, and the tension of the wire 35, that is, the tension adjustment can be performed by this adjustment. For example, compared to the method of adjusting the tensile force described in patent document 1, it is easy to finely adjust the tensile force and to maintain the adjusted tensile force. Further, since the variation in the pulling force can be reduced and the pulling force can be stabilized, the frictional force acting between the plurality of driving members 31 and the forceps 12 can be stabilized. Therefore, the accuracy of the external force estimation can be easily improved as compared with a method in which the frictional force acting between the plurality of driving members 31 and the forceps 12 is unstable.

By improving the accuracy of external force estimation in the above manner, a safer operation can be realized with the surgical tool 1, and an operation with fewer complications can be realized. In addition, the QOL of the patient is easy to be improved, the burden of a doctor in the operation process is reduced, and the learning curve of the operation robot is improved. In addition, QOL referred to herein is an abbreviation for quality of life (life), and is described in the same manner as below.

Further, since the relative positions of the plurality of pulley rotating shafts 46 and the plurality of fixed blocks 51 in the direction of the rotation axis L can be changed, the rotation of the pulley 41 is not easily hindered. For example, in the case where the plurality of pulley rotation shafts 46 are fixed to the first casing section 21 and the plurality of fixing blocks 51 are fixed to the second casing section 22, even if the combined length of the pulley rotation shafts 46 and the fixing blocks 51 is different from the interval between the first casing section 21 and the second casing section 22, the combined length can be adjusted by changing the relative position. Therefore, the influence of the fixation is not easily transmitted to the pulley 41 supported by the pulley rotating shaft 46, and the rotation is not easily hindered.

In the case where three pulleys 41 are provided as in the present embodiment, the arrangement positions of the three pulleys 41 can be easily made to approach or separate from each other. In other words, even after the arrangement position of one of the pulleys 41 is fixed, the arrangement position of the other pulley 41 is easily moved closer to or farther from.

For example, in the case where only the pulley rotating shaft 46 is provided without a plurality of fixing blocks 51, when the arrangement position of any one of the pulleys 41 is fixed, the end portions of the pulley rotating shaft 46 corresponding to any one of the pulleys 41 are brought into contact with the first casing section 21 and the second casing section 22, respectively. At this time, the first and second casing sections 21 and 22 approach each other, and the interval between the first and second casing sections 21 and 22 becomes equal to the length of the pulley rotation shaft 46. That is, the end portions of the pulley rotating shaft 46 corresponding to the other pulleys 41 also abut against the first casing section 21 and the second casing section 22, respectively. In this way, even if the other pulley 41 is to be disposed at a position close to or away from the other pulley 41, the frictional force acting on the surface where the end of the pulley rotation shaft 46 corresponding to the other pulley 41 abuts against the first casing section 21 and the second casing section 22 is likely to increase, and therefore it is difficult to bring the other pulley 41 to a position close to or away from the other pulley.

In contrast, if the relative position of the pulley rotation shaft 46 and the fixed block 51 can be changed, the first casing section 21 and the second casing section 22 do not approach each other even if the arrangement position of any one of the pulleys 41 is fixed. That is, the frictional force acting on the abutment surface between the pulley rotation shaft 46 corresponding to the other pulley 41 and the first casing section 21, and the frictional force acting on the abutment surface between the fixed block 51 and the second casing section 22 are not easily increased. Therefore, even after the arrangement position of one pulley 41 is fixed, the arrangement positions of the other pulleys 41 can be easily moved closer to or farther from each other.

Also, since the combined length is adjusted by changing the relative position, a load is not easily applied to the first and second case portions 21 and 22. For example, with the first and second casing sections 21 and 22, the load may deform or break the first and second casing sections 21 and 22. Since a load is not easily applied in the above case, deformation or breakage of the first and second casing portions 21 and 22 can be easily suppressed.

The plurality of pulley rotation shafts 46 are pressed against the first case portion 21 and the plurality of fixing blocks 51 are pressed against the second case portion 22 using the plurality of pulley long holes 23 and the plurality of fixing screws 56, whereby the arrangement positions of the plurality of pulleys 41 with respect to at least one of the plurality of driving members 31 and the forceps 12 can be fixed. By increasing the biasing force, the arrangement position can be reliably fixed, and by weakening the biasing force, the arrangement position can be easily changed.

The relative positional relationship between the pulley rotary shaft 46 and the fixed block 51 in the direction of the rotation axis L can be changed by using the tip 49 of the pulley rotary shaft 46 extending in the direction of the rotation axis L and the recess 52 of the fixed block 51 fitted to the tip 49. Further, the relative positional relationship between the pulley rotating shaft 46 and the fixed block 51 in the direction intersecting the direction of the rotation axis L can be maintained.

The plurality of driving members 31 are disposed between the plurality of pulleys 41 and the forceps 12, and the reciprocating movement of the plurality of driving members 31 is transmitted to the forceps 12 by the wire 35 wound around the plurality of pulleys 41, thereby easily adjusting the tension of the wire 35.

Compared to the pulley 141 provided with the spiral groove 142, even if the phase of the pulley 41 changes, it is easy to suppress the position of the wire 35 from changing in the Y-axis direction, and to stabilize the tension of the wire 35. That is, since the variation in the position of the wire 35 in the Y-axis direction is suppressed, the variation in the path length along which the wire 35 is arranged is easily suppressed, and the tension of the wire 35 is easily stabilized.

Therefore, the frictional force acting between the plurality of driving members 31 and the forceps 12 can be easily stabilized, and the accuracy of external force estimation can be easily improved as compared with a method in which the frictional force acting between the plurality of driving members 31 and the forceps 12 is unstable. By improving the accuracy of external force estimation in the above manner, a safer operation can be realized with the surgical tool 1, and an operation with fewer complications can be realized. In addition, the QOL of the patient is easy to be improved, the burden of a doctor in the operation process is reduced, and the learning curve of the operation robot is improved.

Compared to the pulley 141 provided with the spiral groove 142, it is easier to suppress the position of the wire 35 in the Y-axis direction when entering the grooves 42 and the position of the wire 35 in the Y-axis direction when exiting the grooves 42 from the phases of the pulleys 41. Therefore, when the wire material 35 is wound around the plurality of pulleys 41, it is less necessary to pay attention to the phases of the plurality of pulleys 41. In other words, the operation of winding the wire material 35 around the plurality of pulleys 41 is facilitated.

In addition, the technical scope of the present disclosure is not limited to the above embodiments. In addition, various modifications may be made within the technical scope of the present disclosure without departing from the gist of the present disclosure. For example, in the above-described embodiment, the forceps 12 are provided to the surgical tool 1, but other instruments for surgery may be provided, and this is not limitative.