Pulley device and pulley guard for articulating surgical instruments

Abstract

A surgical robotic instrument comprising: a shaft; an end effector element; a joint connecting the end effector element to the shaft, the joint comprising: a first link drivable by a first pair of drive elements, the first link allowing the end effector element to rotate about a first axis transverse to a longitudinal axis of the shaft; a second link drivable by a second pair of drive elements; a pulley arrangement about which the second pair of drive elements is constrained to move, the pulley arrangement comprising a first pulley block rotatable about the first axis and a second pulley block proximal to the first pulley block and comprising a first pulley rotatable about a second axis and a second pulley rotatable about a third axis parallel to and offset from the second axis; and a clevis unit comprising two arms supporting pulleys of the pulley arrangement and a pulley guard extending from one of the arms to protect one of the first pulley and the second pulley.

Description

[0001] This application is a divisional application of Chinese invention patent application No. 201880037974.3 (PCT International Application No. PCT / GB2018 / 051541), filed on June 6, 2018, entitled "Pulley Device and Pulley Protector for Articulated Surgical Instruments". Technical Field

[0002] This invention relates to a pulley protector and pulley device for articulated robotic surgical instruments. Background Technology

[0003] The use of robots to assist in and perform surgery is known. Figure 1 A typical surgical robot 100 is shown, comprising a base 108, an arm 102, and an instrument 105. The base supports the robot and is rigidly attached to, for example, an operating room floor, operating room ceiling, or trolley. The arm extends between the base and the instrument. The arm is hinged along its length by a plurality of flexible joints 103 for positioning the surgical instrument relative to the patient in a desired location. The surgical instrument is attached to the distal end 104 of the robotic arm. The surgical instrument pierces the body of the patient 101 at a port 107 to access the surgical site. At its distal end, the instrument includes an end effector 106 for engagement during medical procedures.

[0004] Figure 2 A typical surgical instrument 200 for performing robotic laparoscopic surgery is shown. The surgical instrument includes a base 201 through which the instrument is connected to a robotic arm. An axis 202 extends between the base 201 and a joint 203. The joint 203 terminates at an end effector 204. Figure 2 The diagram shows a pair of serrated clamps serving as an end effector 204. A joint 203 allows the end effector 204 to move relative to the axis 202. It is desirable to provide at least two degrees of freedom for the movement of the end effector 204 via the joint.

[0005] Figure 3 An example of a known surgical instrument 300 is shown, in which an end effector 204 is allowed to move relative to an axis 202 via a pitch joint 301 and two yaw joints 302. Joint 301 allows the end effector 204 to rotate about a pitch axis 303. Joints 302 allow each jaw of the end effector 204 to rotate about a yaw axis 304. These joints are driven by cables 306, 307, and 308. A pulley 305 is used to guide cables 307 and 308 from their channels across the pitch joints to the yaw joints. Pulley 305 is offset from the central axis of joint 203.

[0006] In typical laparoscopic surgery, surgeons utilize numerous instruments and therefore frequently switch between them. Therefore, it is desirable to minimize the time spent and maximize the ease of detaching an instrument from the robotic arm and attaching different instruments. Additionally, it is desirable to minimize the time spent setting up instruments to be ready for use once they are attached to the robotic arm.

[0007] Thus, surgical instrument 300 can be attached to the distal end of the robotic arm via an instrument interface at its proximal end. The instrument interface can connect to or engage with the interface of the robotic arm. Mechanical actuators for the drive instruments (e.g., connectors 301 and 302) can be transmitted from the robotic arm to the instrument via the robotic arm interface and the instrument interface. Summary of the Invention

[0008] According to the present invention, a surgical robot instrument is provided, comprising: a shaft; an end effector element; a joint connecting the end effector element to the shaft, the joint comprising: a first joint actuated by a first pair of drive elements, the first joint allowing the end effector element to rotate about a first axis transverse to a longitudinal axis of the shaft; a second joint actuated by a second pair of drive elements; a pulley assembly, the second pair of drive elements constrained to move about the pulley assembly, the pulley assembly including a first pulley group and a second pulley group, the first pulley group being rotatable about a first axis, the second pulley group being located proximal to the first pulley group and including a first pulley and a second pulley, the first pulley being rotatable about a second axis, the second pulley being rotatable about a third axis parallel to and offset from the second axis; and a U-shaped clamping unit including two arms and a pulley protector, the arms supporting the pulleys of the pulley assembly, the pulley protector extending from one of the arms to protect one of the first and second pulleys.

[0009] The second connector can be located on the far side of the first connector.

[0010] The second and third axes can deviate from the first axis.

[0011] The second and third axes can deviate from the first axis in a direction transverse to the longitudinal axis of the axis.

[0012] The second and third axes can lie in a plane perpendicular to the longitudinal axis of the axis.

[0013] The first axis may intersect with the longitudinal axis of the shaft. The second and third axes may be parallel to the first axis.

[0014] The first of these two arms can support the first pulley, and the second of these two arms can support the second pulley.

[0015] The first arm and the second arm can be located on opposite sides of a plane that includes the longitudinal axis and is transverse to the first axis.

[0016] The U-shaped clamp unit may include a first pulley protector extending from the first arm to protect the first pulley and a second pulley protector extending from the second arm to protect the second pulley.

[0017] The first pulley protector and the second pulley protector may be located on opposite sides of a first plane that includes the longitudinal axis of the shaft and is transverse to the first axis, and on opposite sides of a second plane that includes both the longitudinal axis of the shaft and the first axis.

[0018] The first pulley protector may include an inner wall that partially surrounds the first pulley, and the second pulley protector may include an inner wall that partially surrounds the second pulley.

[0019] The pulley protector can be located within the internal space of the U-shaped clamp unit defined by the profile of the shaft.

[0020] The U-shaped clamp unit may further include a first drive element guide and a second drive element guide, wherein one drive element of the first drive element pair passes through the first drive element guide and the other drive element of the first drive element pair passes through the second drive element guide, and each of the first drive element guide and the second drive element guide is located between the first arm and the second arm of the U-shaped clamp unit.

[0021] The pulley guard can extend between one of the arm and one of the drive element guides.

[0022] The first pulley protector may extend between the first arm and the first drive element guide, and the second pulley protector may extend between the second arm and the second drive element guide.

[0023] The first drive element guide and the second drive element guide may be located on opposite sides of the plane containing the longitudinal axis of the shaft and the first axis. Attached Figure Description

[0024] This disclosure will now be described by way of example with reference to the accompanying drawings. In the drawings:

[0025] Figure 1 The surgical robot performing the procedure is shown.

[0026] Figure 2 Known surgical instruments are shown;

[0027] Figure 3 A known arrangement of the actuator at the articulated end of a surgical instrument is shown;

[0028] Figure 4 The surgical robot was shown;

[0029] Figure 5a , Figure 5b , Figure 5c and Figure 5d The distal end of the surgical instrument is shown;

[0030] Figure 6a and Figure 6b The linear configuration is shown. Figures 5a to 5d The pulley device at the distal end of the surgical instrument;

[0031] Figure 7 It shows various non-direct configurations Figures 5a to 5d The pulley device at the distal end of the surgical instrument;

[0032] Figure 8 It shows Figures 5a to 5d The pulley device shown has an offset pulley. Detailed Implementation

[0033] Figure 4 A surgical robot with an arm 400 extending from a base 401 is shown. The arm includes multiple rigid limbs 402. The limbs are coupled via rotary joints 403. The proximal limb 402a is coupled to the base via joint 403a. It and other limbs are coupled in series via other joints in joint 403. A wrist 404 consists of four separate rotary joints. The wrist 404 couples one limb (402b) to the distal limb (402c) of the arm. The distal limb 402c carries an attachment 405 for a surgical instrument 406. Each joint 403 of the arm has one or more motors 407 and one or more position and / or torque sensors 408, the motors 407 being operable to cause rotational movement at the corresponding joint, and the position and / or torque sensors 408 providing information about the current configuration and / or load at that joint. The motors may be arranged proximal to the joint whose movement is driven by the motors to improve weight distribution. For clarity, in Figure 4 Only some motors and sensors are shown. The arm can be roughly as described in our co-pending patent application PCT / GB2014 / 053523.

[0034] The arm terminates in an attachment 405 for docking with the instrument 406. The instrument 406 can take the following actions: Figure 2The attachment 405 includes a drive assembly for driving the joints of the instrument and a drive assembly interface for engaging the instrument interface 406. Movable interface elements of the drive assembly interface mechanically engage corresponding movable interface elements of the instrument interface to transfer drive from the robot arm to the instrument. During typical operation, one instrument can be exchanged with another several times. Therefore, the instrument can be attached to and detached from the robot arm during operation. When the drive assembly interface and the instrument interface engage with each other, features of the drive assembly interface and the instrument interface help align them to reduce the precision required for user alignment.

[0035] Instrument 406 includes an end effector for performing the operation. The end effector can take any suitable form. For example, the end effector can be a smooth clamp, a serrated clamp, a gripper, a pair of scissors, a needle for suturing, a camera, a laser, a knife, a suture device, a cauterizer, or a suction device. (See also: Regarding...) Figure 2 The device includes a joint between a device axis and an end effector. The joint may include one or more connectors that allow the end effector to move relative to the device axis. One or more connectors in the joint are actuated by a drive element (e.g., a cable). These drive elements are fastened at the other end of the device axis to an interface element of the device interface. Thus, the robotic arm transmits drive to the end effector as follows: movement of the drive component interface element causes movement of the device interface element, which in turn causes movement of the drive element, which in turn causes movement of the joint connector, which in turn causes movement of the end effector.

[0036] A controller for the motor, torque sensor, and encoder is distributed along with the robotic arm. The controller is connected to a control unit 409 via a communication bus. The control unit 409 includes a processor 410 and a memory 411. The memory 411 stores software in a non-transient manner that can be executed by the processor to control the operation of the motor 407, thereby causing the arm 400 to operate in the manner described herein. Specifically, the software can control the processor 410 to drive the motor (e.g., via a distributed controller) based on inputs from a sensor 408 and from a surgeon command interface 412. The control unit 409 is coupled to the motor 407 to drive the motor 407 based on the output generated by the execution of the software. The control unit 409 is coupled to the sensor 408 to receive sensed inputs from the sensor and to the command interface 412 to receive inputs therefrom. The various couplings may be, for example, cables or fiber optic cables, or may be provided via wireless connections. The command interface 412 includes one or more input devices through which a user can request movement of the end effector in a desired manner. Input devices can be, for example, manually operable mechanical input devices (such as control handles or joysticks) or non-contact input devices (such as optical attitude sensors). Software stored in memory 411 is configured to move the arm and instrument joints accordingly in response to these inputs and according to a predetermined control strategy. The control strategy may include safety features that mitigate the movement of the arm and instrument in response to command inputs. Therefore, in summary, the surgeon at command interface 412 can control the movement of instrument 406 in a manner suitable for performing the desired surgical procedure. Control unit 409 and / or command interface 412 may be located remotely from arm 400.

[0037] Figure 5a and Figure 5b A relative view of the distal end of an exemplary surgical instrument is shown. Figure 5a and Figure 5b In this example, end effector 501 includes a pair of end effector elements 502, 503, which are depicted as a pair of opposing serrated jaws. It will be understood that this is for illustrative purposes only. The end effector can take any suitable form, such as those described above. End effector 501 is connected to instrument shaft 504 via joint 505. Joint 505 includes a connector that allows movement of end effector 501 relative to shaft 504. In this example, joint 505 includes three connectors. A first connector 506 allows end effector 501 to rotate about a first axis 510. The first axis 510 is transverse to the longitudinal axis of shaft 511. The first connector 506 is arranged such that shaft 504 terminates in connector 506 at its distal end. A second connector 507 allows first end effector element 502 to rotate about a second axis 512. The second axis 512 is transverse to the first axis 510. A third connector 513 allows second end effector element 503 to rotate about the second axis 512.

[0038] The first end actuator element 502 and the second end actuator element 503 can rotate independently about the second axis 512 via the second connector and the third connector. The end actuator elements can rotate in the same or different directions via the second connector and the third connector. The first end actuator element 502 can rotate about the second axis, while the second end actuator element 503 does not rotate about the second axis.

[0039] In the figure, both the second connector 507 and the third connector 513 allow rotation about the same axis 512. However, the second and third connectors can alternatively allow the end effector elements to rotate about different axes. The axis of rotation of one end effector element may be offset from the axis of rotation of the other end effector element along the longitudinal direction of shaft 504. The axis of rotation of one end effector element may be offset from the axis of rotation of the other end effector element in a direction transverse to the longitudinal direction of shaft 504. The axis of rotation of one end effector element may not be parallel to the axis of rotation of the other end effector element. The axes of rotation of end effector elements 502 and 503 may be offset from each other and / or angled relative to each other along the longitudinal direction of the shaft and / or along a direction perpendicular to the longitudinal direction of the shaft. This may be desirable because the end effector elements are asymmetrical. For example, in an electrosurgical element, the first end effector element may be powered while the second end effector element is not powered and is insulated from the first end effector element. To assist this, the axes of rotation of the two end effector elements may be offset in a direction perpendicular to the longitudinal direction of the shaft. In another example, the first end actuator element can be a blade, while the second end actuator element can be a flat cutting surface. To facilitate the use of the blade, the rotation axes of the two end actuator elements can be at an angle to each other.

[0040] Figure 5a and Figure 5b A linear configuration of a surgical instrument with the end effector aligned with shaft 504 is shown. In this orientation, the longitudinal axis of shaft 511 coincides with the longitudinal axis of the joint and the longitudinal axis of the end effector. The joints of the first, second, and third connectors allow the end effector to assume a range of postures relative to the shaft.

[0041] Joint 505 includes a support body 509. At one end, the support body 509 is connected to shaft 504 via a first connector 506. At its other end, the support body 509 is connected to end effector 501 via a second connector 507 and a third connector 513. Thus, the first connector 506 allows the support body 509 to rotate relative to shaft 504 about a first axis 510; and the second connector 507 and the third connector 513 allow end effector elements 502, 503 to rotate relative to the support body 509 about a second axis 512. The support body 509 supports connectors 507 and 513 and may also be referred to as a support. In the linear configuration shown in FIG. 5, connectors 507 and 513 are located distal to connector 506 in the direction of the longitudinal axis of shaft 511 (i.e., connector 506 is located proximal to connectors 507 and 513 in the direction of the longitudinal axis of shaft 511). It should be understood that in other configurations of surgical instruments, connectors 507 and 513 will be located distal to connector 506.

[0042] The device also includes a U-shaped clamp unit 508. The U-shaped clamp unit is located at the distal end of the shaft 504. The shaft may terminate at the U-shaped clamp unit. When the device is in the straight configuration shown in FIG. 5, the U-shaped clamp unit is located proximal to the support 509 in the direction of the longitudinal axis 511 (i.e., the support is located distal to the U-shaped clamp unit). It should be understood that there are other device configurations where the U-shaped clamp unit is located proximal to the support. The U-shaped clamp unit includes a base 532. This base is located at the proximal end of the U-shaped clamp unit. The base 532 includes an outer wall or surface defining the circumference of the U-shaped clamp unit. The outer surface of the base is flush with the outer surface of the distal end of the shaft 504. The U-shaped clamp unit also includes a pair of opposing arms 530 and 531 supporting the first connector 506. These arms extend from the base 532. These arms extend in a direction parallel to the longitudinal axis of the shaft 511. These arms extend toward the distal end of the device. Arms 530 and 531 are located on opposite sides of a plane containing the longitudinal axis of shaft 511 and transverse to the rotation axis 510 of the first joint 506. These arms may be evenly spaced around the circumference of the U-shaped clamp unit 508. That is, these arms may be spaced apart in the direction of the rotation axis 510. These arms may also be referred to herein as forks.

[0043] The U-clamp unit also includes drive element guides 533 and 534. The drive elements will be described below. Each guide 533, 534 is in the form of a block protruding from the base 532 of the U-clamp unit. In the linear configuration shown in FIG. 5, this block protrudes toward the distal end of the instrument. Equivalently, this block can be described as protruding distally in a direction parallel to the longitudinal axis of shaft 511. Each drive element guide includes an outer surface or sidewall (shown at 535 for guide 534). The outer wall is flush with the outer surface of the base 532. The drive element guide also includes a top surface (shown at 536 for guide 534). In the example shown, the top surface of the drive element guide is chamfered. Each drive element guide also includes a hole, shown at 537 for guide 533. This hole extends through the guide in a direction parallel to the longitudinal axis of shaft 511. The drive element guides are located on opposite sides of the plane containing both the longitudinal axis of shaft 511 and the first rotation axis 510 of connector 506. Each drive element guide is located between the two forks 530 and 531. The guides may be equidistantly spaced around the circumference of the base (as shown in the figure). Thus, in the figure, the guides are spaced apart in a direction parallel to the rotation axis 512 of connectors 507 and 513. In some examples, drive element guides 533 and 534 may be separate and distinct blocks. In other examples, drive element guides 533 and 534 may be parts of the same block. In other words, in some examples, drive element guides 533 and 534 may be combined to form a single block.

[0044] The U-shaped clamp unit also includes pulley protectors 538 and 539. The pulley protectors are... Figure 5a and Figure 5b The middle section is depicted with dashed lines. This is to show the components of the instrument, which would otherwise be obscured by the pulley guards. Figure 5c and Figure 5d It shows the relationship with Figure 5a and Figure 5b The same surgical instruments are shown, but the pulley protectors are shown in solid lines. Each pulley protector extends from the corresponding fork. Specifically, pulley protector 538 extends from fork 530, while pulley protector 539 extends from tooth 531. The pulley protectors are said to abut against the fork. In this arrangement, the pulley protectors can be easily operated to increase the rigidity of the fork. Each pulley protector extends from a single side (i.e., edge) of the fork. That is, each pulley protector abuts against a single side or edge of the fork. In the example shown, each pulley protector extends between the fork and the drive element guide. Specifically, pulley protector 538 extends between fork 530 and drive element guide 533, while pulley protector 539 extends between fork 531 and drive element guide 534. Appropriately, each pulley protector abuts against the drive element guide.

[0045] The pulley protector also extends distally from the base 532 of the U-shaped clamp unit. In the example shown, the pulley protector protrudes from the base to a position flush with the lower edge of the chamfer 536 (i.e., the edge between the chamfer and the sidewall 535 of the drive element guide). However, it should be understood that in other examples, the pulley protector may protrude to a greater or lesser extent. The pulley protector includes an outer wall flush with the outer walls of the drive element guide and the fork (in... Figure 5c (The pulley protector 538 is shown at 540). It can be seen that the pulley protector occupies the internal space of the U-shaped clamp unit between the drive element guide and the fork. That is, the pulley protector occupies the internal space defined by the protruding contours of the U-shaped clamp unit 508 and the shaft 504. Since the pulley protectors extend between the fork and the drive element guide in this example, they may be referred to herein as fillets.

[0046] Pulley protectors 538 and 539 are located on opposite sides of the plane containing the longitudinal axis of shaft 511 and the rotation axis 510 of the first joint 506. The pulley protectors are also located on opposite sides of the plane containing axis 511, transverse to the rotation axis 510 of the first joint 506. Therefore, the pulley protectors can be said to be obliquely opposite each other. Alternatively, the pulley protectors can be said to be obliquely oriented relative to the forks 530 and 531. That is, the pulley protectors can be located on an axis oblique to the axis where the forks 530 and 531 are located.

[0047] The pulley protector can be a separate component that is fastened to or attached to the fork. Alternatively, the pulley protector can be integrally formed with the fork (and, in the example shown, the drive element guide).

[0048] The connector of joint 505 is driven by drive elements. The drive elements are elongated elements extending from the connector in the joint through shaft 504 to the instrument interface. Each drive element can be laterally bent along its principal dimension, at least in those areas where it engages with the internal components of the joint and instrument interface. In other words, each drive element can bend laterally along its longitudinal axis in specific areas. This flexibility allows the drive elements to wrap around the internal structures of the instrument, such as connectors and pulleys. The drive elements can be completely flexible laterally along their longitudinal axis. The drive elements can also be non-flexible along their principal dimension. The drive elements can resist compressive and tensile forces applied along their length. In other words, the drive elements can resist compressive and tensile forces acting in the direction of their longitudinal axis. The drive elements can have a high modulus. The drive elements can remain taut during operation; they cannot be allowed to slack off. Therefore, the drive elements are able to transmit actuation from the instrument interface to the connector. The drive elements can be, for example, cables.

[0049] Each connector can be driven by a drive element. (See reference) Figure 5a and Figure 5b The first connector 506 is driven by the first drive element pair A1, A2. It can be seen that drive elements A1, A2 extend through the holes of drive element guides 533, 534, respectively. Therefore, the drive element guides surround drive elements A1, A2 along a portion of their length. Thus, the drive element guides hold drive elements A1, A2 and shield them from interference in the distal region of the end effector 501. The second connector 507 is driven by the second drive element pair B1, B2. The third connector is driven by the third drive element pair C1, C2. Therefore, each connector of the device 501 is driven by its own drive element pair. In other words, each connector 505 is driven by a dedicated drive element pair. The connectors can be driven individually. The drive element pairs can be constructed as single pieces, such as for... Figure 5a and Figure 5b The third drive element pair is shown in the diagram. In this case, each piece is fastened to the connector at a single point. For example, the third drive element pair C1, C2 includes a spherical feature 520 fastened to the third connector 513. This ensures that when the drive element pair is driven, the drive is converted into movement of the connector about its axis. Alternatively, the drive element pair can be constructed as two pieces. In this case, each separate piece is fastened to the connector. The first, second, and third drive element pairs extend from the distal end of the shaft connected to the joint through the instrument shaft to the proximal end of the shaft connected to the drive mechanism of the instrument interface.

[0050] Figure 5a and Figure 5b The surgical instruments also include a pulley system, with a second and third pair of drive elements constrained to move around the pulley system. The pulley system... Figure 6a and Figure 6b This is better illustrated in the image. Figure 6a and Figure 6b Support 509 is not shown in the diagram to illustrate the pulley mechanism more clearly. Figure 6a and Figure 6b Pulley guards 538 and 539 are not shown in the diagram to illustrate the pulley assembly more clearly. The pulley assembly includes a first pulley block 601. The first pulley block 601 is rotatable about a first axis 510. Therefore, the first pulley block 601 rotates about the same axis as the first joint 506. The pulley assembly also includes a second pulley block 602. The pulley assembly also includes a pair of directional pulleys 603, which are described in more detail after the description of the pulley assembly.

[0051] The pulley device is also Figure 7 As shown in the diagram, the support body, U-shaped clamp unit, first connector, and first drive element have been... Figure 7 All text is omitted to more clearly show the pulley mechanism.

[0052] The first pulley assembly 601 includes a first pulley 705 and a second pulley 706. Both the first pulley 705 and the second pulley 706 rotate about a first axis 510. The first pulley 705 and the second pulley 706 are located on opposite sides of the first joint 506 in the longitudinal direction of the shaft 504. The first pulley 705 and the second pulley 706 are located at opposite ends of the first axis 510. The first pulley 705 and the second pulley 706 are located on opposite sides of the first drive element pair A1, A2. The first pulley assembly 601 is supported by arms 530 and 531 of the U-shaped clamp unit 508. Both the first pulley 705 and the second pulley 706 are rotatably mounted to the U-shaped clamp unit. Pulley 705 is mounted to arm 531, while pulley 706 is mounted to arm 530.

[0053] The second pulley assembly includes a first pulley 701 and a second pulley 702. The second pulley assembly is supported by arms 530 and 531 of a U-shaped clamp unit 508. Both the first pulley 701 and the second pulley 702 of the second pulley assembly are rotatably mounted to the U-shaped clamp unit. Pulley 701 is mounted to arm 531, while pulley 702 is mounted to arm 530. Therefore, each arm of the U-shaped clamp unit supports one pulley in the second pulley assembly. The second pulley assemblies 701 and 702 are further supported by drive element guides 533 and 534. The first pulley 701 is supported by drive element guide 533, while the second pulley 702 is supported by drive element guide 534. Therefore, each drive element guide supports one pulley in the second pulley assembly. Thus, pulley 701 is supported by arm 531 and drive element guide 533; while pulley 702 is supported by arm 530 and drive element guide 534. Pulleys 701 and 702 can be mounted to a spindle, which is fastened to arms 530, 531 and drive element guides 533 and 534. The first pulley 701 is rotatable about a third axis 703 parallel to the first axis 510. The third axis 703 is offset from the first axis 510 both longitudinally and transversely to the longitudinal direction of the axis. The second pulley 702 is rotatable about a fourth axis 704 parallel to the first axis 510. The fourth axis 704 is offset from the first axis 510 both longitudinally and transversely to the longitudinal direction of the axis. The third and fourth axes are parallel but offset from each other. The third and fourth axes are offset from each other along the direction of the rotation axis 512 of joints 507 and 513. The third axis 703 and the fourth axis 704 are in the same plane perpendicular to the longitudinal direction of axis 511.

[0054] Figure 8The distal end of the surgical instrument is shown in different views, which more clearly show the off-axis deviation of the first pulley 701 and the second pulley 702 of the second pulley assembly. By deviating the first pulley 701 and the second pulley 702, the drive element wound around each pulley is able to extend axially downward after being wound around the pulley. Figure 6a As shown, the first pulley 701 and the second pulley 702 of the second pulley block 602 are located on opposite sides of the first joint 506 in the longitudinal direction of the shaft 504. The first pulley 701 and the second pulley 702 are located on opposite sides of the first drive element pair A1, A2. The offset of pulleys 702 and 701 in both directions perpendicular to the longitudinal axis of shaft 511 and the rotation axis 510 of joint 506 provides space for accommodating pulley guards 538 and 539.

[0055] The second pulley assembly is located between the first pulley assembly and the instrument interface end of the shaft. Appropriately, as shown in the figure, the second pulley assembly is located within the shaft. Therefore, the second pulley assembly 602 is located proximal to the first pulley assembly 601 along the longitudinal axis of the shaft 511 (i.e., the first pulley assembly 601 is located distal to the second pulley assembly 602). Since both pulley assemblies are supported by the U-shaped clamp unit 508, it will be understood that the second pulley assembly 602 is located proximal to the first pulley assembly regardless of the configuration of the instrument and the end effector. By positioning the second pulley assembly at the distal end of the shaft 508, the distance between the first and second joints is reduced compared to an alternative arrangement where the second pulley assembly is located within the joint, thereby reducing the stiffness of the support 509 required to maintain the precise positioning of the end effector 501.

[0056] As mentioned above, the pulley system operates to constrain the movement of the drive elements. More specifically, the second drive elements B1 and B2 are constrained to move around the opposite sides of the first pulley 705 and the second pulley 706 of the first pulley group 601. The second drive elements B1 and B2 are constrained to move around the opposite sides of the first pulley 701 and the second pulley 702 of the second pulley group 601. The second drive elements are constrained to move around the opposite sides of the first pulley 705 of the first pulley group 601 and the first pulley 701 of the second pulley group 602. The second drive elements are constrained to move around the opposite sides of the second pulley 706 of the first pulley group 601 and the second pulley 702 of the second pulley group 602.

[0057] The third driving element pairs C1 and C2 are constrained to move around the opposite sides of the first pulley 705 and the second pulley 706 of the first pulley group 601. The third driving element pairs C1 and C2 are constrained to move around the opposite sides of the first pulley 701 and the second pulley 702 of the second pulley group 601. The third driving element pairs are constrained to move around the opposite sides of the first pulley 705 of the first pulley group 601 and the first pulley 701 of the second pulley group 602. The third driving element pairs are constrained to move around the opposite sides of the second pulley 706 of the first pulley group 601 and the second pulley 702 of the second pulley group 602.

[0058] The second and third drive element pairs are each constrained to extend beyond the first connector 506 to reach the second and third connectors, respectively. Therefore, the first drive element B1 of the second drive element pair passes on one side of the first pulley 705 of the first pulley group on the first connector axis 510, and the second drive element B2 of the second drive element pair passes on the opposite side of the second pulley 706 of the first pulley group on the first connector axis 510, such that the lengths of the second drive element pairs B1 and B2 remain the same regardless of how the support 509 rotates around the first connector 506. Similarly, the first drive element C1 of the third drive element pair passes on one side of the second pulley 706 of the first pulley group on the first connector axis 510, and the second drive element C2 of the third drive element pair passes on the opposite side of the first pulley 705 of the first pulley group on the first connector axis 510, such that the lengths of the third drive element pairs C1 and C2 remain the same regardless of how the support 509 rotates around the first connector 506. If the arrangement of the instrument interfaces is symmetrical with respect to the second drive element pairs B1, B2 and the third drive element pairs C1, C2, then for all rotational angles of the support 509 about the first connector 506, the lengths of the second and third drive element pairs are the same. In every configuration of the surgical instrument, the second and third drive element pairs remain taut. They never slack off. Therefore, there is no backlash when any connector of the surgical instrument is articulated. Thus, complete control over all three degrees of freedom of movement of the surgical instrument is achieved in every configuration of the surgical instrument.

[0059] Figure 7The distal ends of five different configurations of surgical instruments are shown. Configuration (c) is the previously mentioned linear configuration, in which the end effector is aligned with the instrument axis. In configurations (a), (b), (d), and (e), rotation about the first connector has occurred relative to configuration (c). In configurations (a), (b), (d), and (e), no rotation about the second or third connector has occurred relative to configuration (c). Starting from configuration (c), pulling drive element A2 (not shown) causes rotation about the first axis 510, resulting in the arrangement of configuration (b). Further pulling drive element A2 causes further rotation about the first axis 510, resulting in the arrangement of configuration (a). Starting from configuration (c), pulling drive element A1 (not shown) causes rotation about the first axis 510 in a direction opposite to that in configurations (a) and (b), resulting in the arrangement of configuration (d). Further pulling drive element A1 causes further rotation about the first axis 510, resulting in the arrangement of configuration (e).

[0060] The rotation of end effector 501 about the first axis 510 is defined by the maximum stroke of the first drive element A1, A2 about the first joint 506. Configuration (a) shows the maximum rotation of end effector 501 about the first axis 510 in one direction, while configuration (e) shows the maximum rotation of end effector 501 about the first axis 510 in opposite directions. In both configurations, the maximum rotation angle relative to the longitudinal axis of shaft 511 is angle φ. The second pulley group 602 is positioned relative to the first pulley group 601 to ensure that the second and third drive elements remain in contact with both the first pulley group 601 and the second pulley group 602 even at the maximum rotation angle φ. For all rotation angles of end effector 501 about the first axis 510, end effector 501 is always located within a cone defined by the tangent connecting the first pulley 701 of the second pulley group and the first pulley 705 of the first pulley group. This tangent is the path taken by the drive element. Figure 7 All configurations show that when the second and third connectors remain Figure 5a and Figure 5b In a linear configuration, the end effector 501 is positioned within the cone. Figure 7 As can be seen, without the second pulley block 602, drive elements B2 and C1 will lose contact with the first pulley block 601 in configuration (a). Without the second pulley block 602, drive elements B1 and C2 will lose contact with the first pulley block 601 in configuration (e).

[0061] For all rotational angles of the end effector relative to the longitudinal axis of the shaft, the second and third drive elements remain in contact with the first and second pulley sets. Therefore, regardless of rotation around the first joint 506, the lengths of the second drive element pairs B1 and B2 remain the same. Furthermore, regardless of rotation around the first joint 506, the lengths of the third drive element pairs C1 and C2 remain the same. Therefore, regardless of how the first joint 506 is driven around the first axis 510, the second pulley set allows tension to be maintained in both the second and third drive elements. Thus, regardless of how the first joint 506 is driven around the first axis 510, control over the second and third drive elements is maintained.

[0062] In the example shown here, each pulley of the first pulley group 601 includes a pair of pulley elements. The first pulley 705 includes an inner pulley element 708 and an outer pulley element 709. The inner pulley element 708 is located between the outer pulley element 709 and the first drive element pair A1, A2. Suitably, the inner pulley element 708 abuts against the outer pulley element 709. The inner pulley element 708 may be fixed together with the outer pulley element 709. The inner pulley element 708 may be integrally formed with the outer pulley element 709. The second pulley 706 includes an inner pulley element 710 and an outer pulley element 711. The inner pulley element 710 is located between the outer pulley element 711 and the first drive element pair A1, A2. Suitably, the inner pulley element 710 abuts against the outer pulley element 711. The inner pulley element 710 may be fixed together with the outer pulley element 711. The inner pulley element 710 can be integrally formed with the outer pulley element 711. Each pulley element includes a groove for accommodating a drive element.

[0063] Suitably, each pulley of the second pulley group 602 includes a pair of pulley elements. The first pulley 701 includes an inner pulley element 712 and an outer pulley element 713. The inner pulley element 712 is located between the outer pulley element 713 and the first drive element pair A1, A2. Suitably, the inner pulley element 712 abuts against the outer pulley element 713. The inner pulley element 712 may be fixed together with the outer pulley element 713. The inner pulley element 712 may be integrally formed with the outer pulley element 713. The second pulley 702 includes an inner pulley element 714 and an outer pulley element 715. The inner pulley element 714 is located between the outer pulley element 715 and the first drive element pair A1, A2. Suitably, the inner pulley element 714 abuts against the outer pulley element 715. The inner pulley element 714 may be fixed together with the outer pulley element 715. The inner pulley element 714 can be integrally formed with the outer pulley element 715. Each pulley element includes a groove for accommodating a drive element.

[0064] The second drive elements B1 and B2 are constrained to move around the inner pulley element 712 of the first pulley of the second pulley group and the outer pulley element 715 of the second pulley of the second pulley group. The second drive elements B1 and B2 are constrained to move around the inner pulley element 708 of the first pulley of the first pulley group and the outer pulley element 711 of the second pulley of the first pulley group.

[0065] The third drive elements C1 and C2 are constrained to move around the outer pulley element 713 of the first pulley of the second pulley group and the inner pulley element 714 of the second pulley group. The third drive elements C1 and C2 are constrained to move around the outer pulley element 709 of the first pulley of the first pulley group and the inner pulley element 710 of the second pulley of the first pulley group.

[0066] Therefore, the second drive element pair B1, B2 has a path symmetrically opposite to the third drive element pair C1, C2 around the first and second pulley sets 601, 602. In a straight configuration of the end effector and shaft-aligned device, the paths of the second drive element pair B1, B2 around the pulley assembly are rotationally symmetrical about the longitudinal axis of shaft 511 with respect to the paths of the third drive element pair C1, C2 around the pulley assembly. The second drive element pair B1, B2 and the third drive element pair C1, C2 are arranged symmetrically to expose from the second pulley set 602 and enter the distal end of the shaft. Figure 7 As is more readily apparent, drive elements B1 and C2 are exposed adjacent to each other on one side of the shaft, and drive elements C1 and B2 are exposed adjacent to each other on opposite sides of the shaft. The arrangement of drive elements B1 and C2 in the shaft is rotationally symmetrical about the longitudinal axis of shaft 511. The second pulley block 602 thus directs the second and third drive element pairs from the first pulley block 601 into the shaft.

[0067] The pulley mechanism of the end effector has now been explained in more detail, making the function of the pulley protector easier to understand. Refer to Figure 6 and... Figure 7 As can be seen, the pulley protector 539 protects the first pulley 701 of the second pulley assembly 602. It also protects the drive elements B1 and C2 wound around the pulley when they extend into the shaft. That is, the pulley protector 539 shields the portion of the drive element extending between the pulley 701 and the distal end of the shaft. (See reference...) Figure 5d As can be seen most clearly, the pulley protector 539 includes an inner wall 541 (only its top edge is visible in the figure), which partially surrounds the drive element wrapped around the pulley 701. This helps to shield the drive element.

[0068] Similarly, pulley protector 538 protects the second pulley 702 of the second pulley assembly 602. It also protects the drive elements B2 and C1 as they extend into the shaft, wound around the pulley. Pulley protector 538 shields the portion of the drive element extending between the pulley 702 and the distal end of the shaft. (See reference...) Figure 5c As can be seen most clearly, the pulley protector 538 includes an inner wall 542 (only its top edge is visible in the figure), which partially surrounds the drive element wrapped around the pulley 702. This helps to shield the drive element.

[0069] Therefore, the pulley protector shields the pulleys of the second pulley group and the drive element wrapped around these pulleys. Thus, the pulley protector can advantageously help prevent unwanted interference with the pulleys and drive element during operation of the end actuator 501.

[0070] Furthermore, the pulley protector can aid in the assembly of the end effector. This is because the pulley protector partially surrounds the drive element that wraps around pulleys 701 and 702. Therefore, the pulley protector can form alignment points that help place pulleys 701 and 702 in the correct position during assembly. For example, the curved surfaces of the inner walls can be used to properly align pulleys 701 and 702 by placing the pulleys such that they are seated within the channels defined by these surfaces. In effect, the pulley protector can impose further constraints on the locations where pulleys 701 and 702 can be placed during assembly. This tighter constraint on the locations where pulleys can be placed helps guide the positioning of the pulleys within the U-shaped clamp unit.

[0071] The pulley system also includes pairs of steering pulleys 716 and 717. These steering pulleys are located in joint 505 between the first joint 506 and the second and third joints 507 and 513. The steering pulleys are positioned to turn the second drive element pairs B1 and B2 from the first pulley group 601 to the second joint 507, and to turn the third drive element pairs C1 and C2 from the first pulley group 601 to the third joint 513. The steering pulleys can be mounted to a support.

[0072] The second drive elements B1 and B2 are constrained to move about the first steering pulley 716. The first steering pulley 716 rotates about the first steering pulley axis 718. The first steering pulley axis 718 forms an angle θ with the first axis 510. The angle θ causes the first drive element B1 in the second drive element pair to turn from the exit point of the first pulley 705 of the first pulley group 601 to the access point 721 on the second connector 507. Suitably, the first steering pulley 716 includes a groove for accommodating the drive element B1. The third drive elements C1 and C2 are constrained not to move about the first steering pulley 716. However, the second drive element C2 in the third drive element pair passes through the first steering pulley 716 between its exit point at the third connector 513 and its access point on the first pulley 705 of the first pulley group 601. The drive element C2 may be partially surrounded by the first steering pulley 716. For example, the drive element C2 may pass partially between the wings of the groove of the first steering pulley 716, but the drive element C2 is not located in the groove of the first steering pulley 716.

[0073] The third drive elements C1 and C2 are constrained to move about the second steering pulley 717. The second steering pulley 717 rotates about the second steering pulley axis 719. The second steering pulley axis 719 forms an angle ψ with the first axis 510. The angle ψ causes the first drive element C1 in the third drive element pair to rotate from the exit point 720 of the second pulley 706 of the first pulley group 601 to the access point on the third connector 513. Suitably, the second steering pulley 717 includes a groove for accommodating the drive element C1. The second drive elements B1 and B2 are constrained not to move about the second steering pulley 717. However, the second drive element B2 in the second drive element pair passes through the second steering pulley 717 between its exit point 720 on the second connector 507 and its access point on the second pulley 706 of the first pulley group 601. The drive element B2 may be partially surrounded by the second steering pulley 717. For example, the drive element B2 may pass partially between the wings of the groove of the second steering pulley 717, but the drive element B2 is not located in the groove of the second steering pulley 717.

[0074] The exit point is the point where the drive element loses contact with the pulley. The entry point is the point where the drive element first contacts the pulley. For a drive element that runs directly from the first pulley to the second pulley, the exit point of the drive element from the first pulley and the entry point of the drive element on the second pulley are points on lines tangent to both the first and second pulleys. The exit point is the point where this tangent intersects the first pulley, and the entry point is the point where this tangent intersects the second pulley. This is for illustrative purposes only, and the thickness of the drive element is considered negligible. Therefore, in reality, the tangent has a thickness equal to the thickness of the drive element, where the exit point is where one side of the tangent intersects the first pulley, and the entry point is where the other side of the tangent intersects the second pulley.

[0075] The steering pulley 716 causes the drive element B1 to wrap more completely around the second joint 507 than it would be without the steering pulley 716, thereby increasing the engagement length between the drive element B1 and the second joint 507. Therefore, the drive element B1 has a greater stroke around the second joint 507, and thus can cause the end actuator element 502 to rotate about the second axis 512 with greater force than it would be without the steering pulley 716. The steering pulley 716 causes a change in the engagement point of the drive element B1 on the second joint 507 relative to its position without the steering pulley 716.

[0076] The steering pulley 717 causes the drive element C1 to wrap more completely around the third joint 513 than it would be without the steering pulley 717, thereby increasing the engagement length between the drive element C1 and the third joint 513. Therefore, the drive element C1 has a greater stroke around the third joint 513, and thus can cause the end actuator element 503 to rotate more about the second axis 512 than it would be without the steering pulley 717. The steering pulley 717 causes a change in the engagement point of the drive element C1 on the third joint 513 relative to its position without the steering pulley 717.

[0077] The steering pulleys are positioned on opposite sides of the joint, each facing the outer edge of the joint. This is in Figure 5a It's easier to see in the middle. For example... Figure 6a As shown, each steering pulley is located on the opposite side of the joint between the joint's longitudinal axis and its outer contour. Appropriately, the diameter of each steering pulley is maximized for the available space. In other words, the steering pulleys are made as large as possible while allowing one drive element to engage the pulley on one side and the other drive element to pass adjacent to the pulley on the opposite side without jamming. The pulleys and both drive elements are enclosed within the joint's contour.

[0078] The first steering pulley 716 lies in a plane defined by three points: (i) the desired exit point of the drive element B1 from the first pulley 705 of the first pulley assembly 601, (ii) the desired access point of the drive element B1 on the second joint 507, and (iii) a point on the boundary of the joint such that the first steering pulley 716 is enclosed within the boundary of the joint when located in the plane. Appropriately, the first steering pulley 716 is as large as possible while remaining within the plane, enclosed within the contour of the joint, without obstructing the path of the drive element C2, and allowing the drive element B1 to move freely about it.

[0079] The second steering pulley 717 lies in a plane defined by three points: (i) the desired exit point of the drive element C1 from the second pulley 706 of the first pulley assembly 601, (ii) the desired access point of the drive element C1 on the third joint 513, and (iii) a point on the boundary of the joint such that the second steering pulley 717 is enclosed within the boundary of the joint when located in the plane. Appropriately, the second steering pulley 717 is as large as possible while remaining within the plane, enclosed within the contour of the joint, without obstructing the path of the drive element B2, and allowing the drive element C1 to move freely about it.

[0080] Determine the desired lead-out and engagement points to allow the desired travel of the drive element around the second and third joints, thereby allowing the end effector element to rotate at its desired maximum speed around the second axis.

[0081] The first and second steering pulleys are located in different planes. For example... Figure 6a As shown, these planes can be symmetrical about a plane perpendicular to the first axis 510. These planes can also be rotationally symmetrical about a plane perpendicular to the first axis 510. Specifically, these planes can be rotationally symmetrical about a line in the plane perpendicular to the first axis 510. When the instrument is in... Figure 6a In the linear configuration shown, these planes are rotationally symmetric about the longitudinal axis of axis 511. This is second-order rotational symmetry. These planes can be reflections of each other in a plane perpendicular to the first axis 510. In the example shown, end effector elements 502 and 503 are rotationally symmetric, and the drive elements are rotationally symmetric about the paths of joints 507 and 513. Alternatively, the axes of end effector elements 502 and 503 can be non-rotationally symmetric and / or the paths of the drive elements about joints 507 and 513 can be asymmetrical. The paths of the drive elements about joints 507 and 513 can be asymmetrical due to the joints having different diameters (to achieve different tension ratios) and / or being positioned with different offsets relative to the centerline of support 509. In either of these alternative examples, the first steering pulley 716 and the second steering pulley 717 will not be rotationally symmetric. They will have different dimensions and / or different positions to cause the drive elements to have the desired lead-out and engagement points as described above.

[0082] Suitablely, the entire pulley assembly, including the first pulley group, the second pulley group, and the steering pulley, is symmetrical about a plane perpendicular to the first axis 510. Specifically, the first portion of the assembly, including the first pulley of the first pulley group 705, the first pulley of the second pulley group 701, and the first steering pulley 716, is rotationally symmetrical about a plane perpendicular to the first axis 510 with respect to the second portion of the assembly, including the second pulley of the first pulley group 706, the second pulley of the second pulley group 702, and the second steering pulley 717. Suitablely, the first portion of the assembly is a reflection of the second portion of the assembly in the plane perpendicular to the first axis 510. The second drive elements, pairs B1 and B2, are constrained to move about the pulley assembly in a manner that is rotationally symmetrical relative to the first axis 510, in which the third drive elements, pairs C1 and C2, are constrained to move about the pulley assembly. Because the pulley assembly has said symmetry, the second and third drive elements constrained to move symmetrically about the pulley assembly also have the same symmetry. Therefore, the paths of the second driving elements B1 and B2 around the pulley device are rotationally symmetrical with respect to the paths of the third driving elements C1 and C2 around the pulley device.

[0083] The above examples describe a U-shaped clamp unit with a pulley system and two pulley protectors. It should be understood that in alternative arrangements, the U-shaped clamp unit may include only a single pulley protector. Furthermore, the pulley protector may be implemented within an end actuator that includes a pulley system different from the one described herein. For example, such a device may not include a steering pulley. In another exemplary variation, the pulley system may be formed by a single pulley element instead of two pulley elements. The pulley system may have additional pulleys not included in the examples described herein.

[0084] In the example described herein, the instrument joint includes three joints. It should be understood that in other examples, the joint may contain more or fewer joints. For example, in an alternative example, the end effector may have only one end effector element. In this case, the joint may not include the third joint 513 or the associated pulley and drive element that drives that joint.

[0085] The applicant hereby separately discloses each individual feature described herein, as well as any combination of two or more such features, provided that such features or combinations can be performed according to this specification as a whole in accordance with common general knowledge of those skilled in the art, regardless of whether such features or combinations of features solve any problem disclosed herein, and not to limit the scope of the claims. The applicant notes that aspects of the invention can consist of any such individual feature or combination of features. In view of the foregoing description, it will be apparent to those skilled in the art that various modifications can be made within the scope of the invention.

Claims

1. A surgical robot device, comprising: axis; End effector elements; A joint that connects the end effector element to the shaft, the joint comprising: A first connector, which can be driven by a first drive element pair, allows the end effector element to rotate about a first axis transverse to the longitudinal axis of the shaft; The second connector can be driven by the second driving element pair; A pulley system, wherein the second drive element is constrained to move about the pulley system, the pulley system comprising: A first pulley system, which is capable of rotating about the first axis; and A second pulley assembly, located near the first pulley assembly and including a first pulley and a second pulley, wherein the first pulley is rotatable about a second axis, and the second pulley is rotatable about a third axis, the third axis being parallel to and offset from the second axis; and The U-shaped clamp unit includes: Base; Two arms that extend from the base and support the pulleys of the pulley assembly; A first drive element guide, located between the two arms, is in the form of a block protruding from the base, and one drive element of the first drive element pair passes through the first drive element guide; and A pulley protector for protecting one of the first pulley and the second pulley, the pulley protector extending from the base and extending between one of the arms and the first drive element guide.

2. The surgical robot device according to claim 1, wherein, The second connector is located on the far side of the first connector.

3. The surgical robot device according to claim 1 or 2, wherein, The second axis and the third axis are offset from the first axis.

4. The surgical robot device according to claim 3, wherein, The second axis and the third axis are offset from the first axis in a direction transverse to the longitudinal axis of the axis.

5. The surgical robot device according to claim 1 or 2, wherein, The second axis and the third axis are located in a plane perpendicular to the longitudinal axis of the axis.

6. The surgical robot device according to claim 1 or 2, wherein, The first axis intersects the longitudinal axis of the shaft.

7. The surgical robot device according to claim 1 or 2, wherein, The second axis and the third axis are parallel to the first axis.

8. The surgical robot device according to claim 1 or 2, wherein, The first arm of the two arms supports the first pulley, and the second arm of the two arms supports the second pulley.

9. The surgical robot device according to claim 8, wherein, The first arm and the second arm are located on opposite sides of a plane that includes the longitudinal axis of the shaft and is transverse to the first axis.

10. The surgical robot device according to claim 8, wherein, The U-shaped clamp unit further includes a second drive element guide located between the first arm and the second arm of the U-shaped clamp unit, with another drive element of the first drive element pair passing through the second drive element guide.

11. The surgical robot device according to claim 10, wherein, The first drive element guide and the second drive element guide are located on opposite sides of a plane containing the longitudinal axis of the shaft and the first axis.

12. The surgical robot device according to claim 10, wherein, The pulley protector extends from the base and between the first arm and the first drive element guide to protect the first pulley, and the U-shaped clamp unit further includes a second pulley protector extending from the base and between the second arm and the second drive element guide to protect the second pulley.

13. The surgical robot device according to claim 12, wherein, The first pulley protector and the second pulley protector are located on opposite sides of a first plane that includes the longitudinal axis of the shaft and is transverse to the first axis, and on opposite sides of a second plane that includes both the longitudinal axis of the shaft and the first axis.

14. The surgical robot device according to claim 12, wherein, The first pulley protector includes an inner wall that partially surrounds the first pulley, and the second pulley protector includes an inner wall that partially surrounds the second pulley.

15. The surgical robot device according to claim 1 or 2, wherein, The pulley protector is located within the internal space of the U-shaped clamp unit defined by the contour of the shaft.

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