Patent Publication Number: US-2022211402-A1

Title: Slider and surgical instrument

Description:
TECHNICAL FIELD 
     The present disclosure relates to a slider and a surgical instrument. 
     BACKGROUND ART 
     In recent years, medical treatments using robots have been proposed to reduce a burden on operators and to save labor in medical facilities. In the surgical field, proposals have been made for medical robots that use a multi-degree-of-freedom manipulator with a multi-degree-of-freedom arm that is remotely controllable by an operator to treat a patient. 
     A surgical instrument used for treatment of a patient is attached to the medical robot. A driving force for operating the surgical instrument is transmitted to the surgical instrument from the medical robot. The driving force transmitted to the surgical instrument is transmitted to an operating part of the surgical instrument through a wire disposed inside the surgical instrument (see Patent Document 1, for example). 
     PRIOR ART DOCUMENTS 
     Patent Documents 
     Patent Document 1: Japanese Patent No. 5542288 
     SUMMARY OF THE INVENTION 
     Problems to be Solved by the Invention 
     Patent Document 1 discloses a configuration in which a wire is annularly disposed, and the annular wire is wound around rotating parts such as pulleys provided at least in an operating part of a surgical instrument. In this configuration, a driving force is transmitted to the rotating parts of the operating part by rotational movement of the wire. 
     When a driving force is transmitted by winding an annular wire around rotating parts such as pulleys, it is preferable to apply a desired tension to the annular wire in order to transmit the driving force. Although it is conceivable to provide a mechanism for applying tension to the annular wire, there has been a problem that addition of the mechanism complicates the structure of the surgical instrument. In a case where a mechanism for applying tension is not provided, there has been a problem that it is difficult to apply a desired tension to the annular wire. 
     It is desirable that the present disclosure provide a slider and a surgical instrument that facilitate arrangement of a wire in an annular shape by applying a desired tension. 
     Means for Solving the Problems 
     A slider according to a first aspect of the present disclosure includes a slider body disposed to be movable in a linear direction relative to a surgical instrument, and two holders disposed on the slider body for holding ends of a wire between the two holders to retain the wire in an annular shape. At least one of the two holders is provided with an insertion hole for inserting and passing the ends of the wire toward an outside from between the two holders. 
     A surgical instrument according to a second aspect of the present disclosure includes: the slider according to the first aspect of the present disclosure; a surgical instrument body that accommodates the slider; and a movable part driven by a driving force transmitted by the slider. 
     With such a configuration, tension is applied to the annular wire by inserting the ends of the wire into the insertion hole and pulling the both ends. By bringing the two holders close to each other in a state where tension is applied to the annular wire, the wire can be held between the two holders. Hence, a desired tension can be applied to the annular wire without providing a mechanism for applying tension to the annular wire, and a desired tension can be easily applied to the annular wire. 
     In the first aspect of the disclosure, it is preferable that the configuration further includes: two protrusions protruding from the slider body to a side where the two holders are disposed, the two holders being disposed between the two protrusions; and a guide provided in the protrusion for guiding the wire to the two holders. 
     With such a configuration, the positions of the two holders relative to the slider body can be stabilized reliably. Further, by guiding the wire to the holder using the guide provided in the protrusion, the position of the wire relative to the holder can be easily stabilized. In particular, even when the slider body causes relative movement in the linear direction, the position of the wire relative to the holder can be easily stabilized. 
     In the first aspect of the disclosure, it is preferable that the guide has the shape of a groove, which is formed in the protrusion and which extends toward the two holders, and the guide is provided with an inclined part, in which a width of the groove narrows toward the two holders. 
     With such a configuration, it is easy to dispose the wire in the guide. Additionally, it is easy to curb an increase in stress acting on a contact portion between the wire and the guide when the slider body causes relative movement in the linear direction. 
     In the first aspect of the disclosure, it is preferable that the configuration further includes a fastener for fixing the two holders so that the two holders are disposed on the slider body and so that the wire is held between the two holders. 
     With such a configuration, it is easy to perform the work of fixing the two holders at desired positions of the slider body and the work of fixing the two holders with the wire held between the two holders. Additionally, both works can be performed simultaneously. 
     Effects of the Invention 
     With the slider of the first aspect and the surgical instrument of the second aspect of the present disclosure, ends of the wire are inserted into the insertion hole and the wire can be held between the two holders while applying tension to the wire, whereby an effect of easily arranging the wire in an annular shape by applying a desired tension is obtained. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a diagram illustrating an embodiment of a surgical instrument of the present disclosure. 
         FIG. 2  is a diagram illustrating a surgical instrument body, slides, and a wire. 
         FIG. 3  is an exploded view of a slide. 
         FIG. 4  is another exploded view of a slide. 
         FIG. 5  is a diagram illustrating a slide and a wire. 
         FIG. 6  is a diagram illustrating another embodiment of a slide. 
     
    
    
     EXPLANATION OF REFERENCE NUMERALS 
       1  . . . surgical instrument,  11  . . . joint (movable part),  20  . . . surgical instrument body,  30  . . . slider,  31  . . . slider body,  32  . . . protrusion,  34 ,  134  . . . guide,  35  . . . inclined part,  41  . . . holder,  42  . . . insertion hole,  45  . . . fastener,  51  . . . wire 
     MODE FOR CARRYING OUT THE INVENTION 
     A surgical instrument according to an embodiment of the present disclosure will be described with reference to  FIGS. 1 to 6 . A surgical instrument  1  of the present embodiment is a surgical instrument held by a multi-degree-of-freedom manipulator having a remotely controllable multi-degree-of-freedom arm. The surgical instrument  1  may have a configuration such as forceps used for treatment of a patient such as endoscopic surgery. 
     As illustrated in  FIG. 1 , the surgical instrument  1  is provided with a shaft  10  and a surgical instrument body  20 . 
     Note that in the present embodiment, for ease of description, a direction in which the shaft  10  extends is defined as the Z axis, and a direction from the base toward the tip end of the shaft  10  is defined as the positive direction. Additionally, the description will be given assuming that a direction orthogonal to the Z axis and in which multiple later-described sliders  30  are arranged is the X axis, and the left direction of the positive direction of the Z axis is the positive direction of the X axis. Further, the description will be given assuming that a direction orthogonal to the Z axis and the X axis is the Y axis, and a direction from a surface of the surgical instrument body  20  on which the sliders  30  are arranged toward the opposite surface is the positive direction of the Y axis. 
     The shaft  10  is a member extending in the positive direction of the Z axis from the surgical instrument body  20 , and is a rod-shaped member to be inserted into the body of the patient. The shaft  10  has a columnar or cylindrical shape. 
     A joint (corresponding to movable part)  11  and forceps  12  are provided at an end of the shaft  10  in the positive direction of the Z axis. 
     The joint  11  is capable of changing the direction of the forceps  12  by a driving force transmitted from a later-described slider  30 . The specific configuration of the joint  11  is not particularly limited, and may be a general configuration. 
     The forceps  12  have a configuration of general forceps for treating a patient. Note that while the present embodiment describes an example in which the forceps  12  are disposed at the tip end of the shaft  10 , other instruments used for treatment of a patient may be disposed at the tip end of the shaft  10 . 
     As illustrated in  FIG. 1 , the surgical instrument body  20  is provided with multiple (three in present embodiment) driven grooves  21  (hereinafter simply referred to as one driven groove  21 ) and multiple (three in present embodiment) sliders  30  (hereinafter simply referred to as one slider  30 .). 
     The driven groove  21  is a long hole provided in an end surface of the surgical instrument body  20  on the negative direction side of the Y axis of two surfaces of the surgical instrument body  20  perpendicular to the Y-axis direction. In other words, the driven groove  21  is a long hole provided on an attachment/detachment surface between the main body  20  and the multi-degree-of-freedom manipulator. Additionally, the driven groove  21  extends along the Z axis. 
     Three driven grooves  21  are arranged side by side at equal intervals in the X-axis direction. The number of the driven grooves  21  can be determined on the basis of the movement (movement based on required specifications) of the joint  11  and/or the forceps  12 , for example. Depending on the required specification, the number of driven grooves  21  may be more or less than three. 
     The slider  30  is configured to receive a driving force transmitted from the multi-degree-of-freedom manipulator and to transmit the driving force to the joint  11  and the forceps  12 . Additionally, the slider  30  is attachable to and detachable from the multi-degree-of-freedom manipulator. 
     One slider  30  is disposed in each of the three driven grooves  21 , and the slider  30  is disposed to be movable in the Z-axis direction inside the driven groove  21 . 
     Among the three sliders  30 , two sliders  30  disposed at a first end and a second end along the X-axis direction are configured to transmit driving force to the joint  11 . Specifically, a wire  51  for transmitting driving force is disposed on each of the two sliders  30 . Among the three sliders  30 , the slider  30  disposed at the center is configured to transmit a driving force to the forceps  12 . Specifically, a rod  55  that transmits the driving force to the forceps  12  is disposed on the slider  30  at the center. 
     Note that in  FIG. 2 , for ease of description, only the sliders  30  and the wires  51  disposed in the driven grooves  21  at both ends in the X-axis direction are illustrated and the slider  30  and the rod  55  at the center are omitted. 
     As illustrated in  FIG. 2 , three first guide pulleys  25 , one second guide pulley  26 , and three third guide pulleys  27  for guiding the wires  51  to the shaft  10  are further provided inside the surgical instrument body  20 . 
     The first guide pulley  25  is disposed at a position closer to the shaft  10  than the slider  30 . Each of the three first guide pulleys  25  has one rotating disk. Among the three first guide pulleys  25 , the two first guide pulleys  25  disposed on the negative direction side of the X axis guide the wire  51  extending from the slider  30  on the negative direction side of the X axis to the inside of the shaft  10 . 
     Similarly to the first guide pulley  25 , the second guide pulley  26  is disposed at a position closer to the shaft  10  than the sliders  30 . The second guide pulley  26  has three rotating disks. The circumferential surfaces of the three disks are provided with grooves through which the wires  51  are guided. 
     One disk has a smaller diameter than the other two disks. The other two disks have the same diameter. The disk having the small diameter is disposed between the disks having a large diameter. Among the three disks of the second guide pulley  26 , the disk having the large diameter and disposed on the negative direction side of the Y axis, together with the first guide pulley  25 , guides the wire  51  extending from the slider  30  on the positive direction side of the X axis to the inside of the shaft  10 . 
     The third guide pulleys  27  are disposed at a position farther from the shaft  10  than the sliders  30 . The three third guide pulleys  27  are arranged side by side in the X-axis direction. The third guide pulley  27  is formed in a cylindrical shape, and a cylindrical surface thereof is provided with multiple grooves through which the wire  51  is guided. 
     In the present embodiment, an example in which three grooves are provided at different positions in the Y-axis direction will be described. At least the third guide pulley  27  on the positive direction side of the X axis is configured such that the wire  51  is movable from the groove, in which the wire  51  is being guided, to the adjacent groove. 
     Among the three third guide pulleys  27 , the third guide pulley  27  on the negative direction side of the X axis and the central third guide pulley  27 , together with the disk having the small diameter among the three disks of the second guide pulley  26 , guide the wire  51  extending from the slider  30  on the negative direction side of the X axis to the inside of the shaft  10 . 
     The third guide pulley  27  on the positive direction side of the X axis, together with the disk having the large diameter and disposed on the positive direction side of the Y axis among the three disks of the second guide pulley  26 , guides the wire  51  extending from the slider  30  on the positive direction side of the X axis to the inside of the shaft  10 . 
     As illustrated in  FIGS. 3 and 4 , the slider  30  is provided with at least a slider body  31 , two holders  41 , and fasteners  45 . As illustrated in  FIG. 3 , the slider  30  may further include spacers  47 . 
     For example, the slider  30  illustrated in  FIG. 3  is the slider  30  disposed in the driven groove  21  on the negative direction side of the X axis, and the slider  30  illustrated in  FIG. 4  is the slider  30  disposed in the driven groove  21  on the positive direction side of the X axis. 
     The slider body  31  is a member formed to extend in the Z-axis direction, and is configured such that the two holders  41  are attachable and detachable. The slider body  31  is provided with two protrusions  32  between which the holders  41  are disposed. Two female screw holes  33  corresponding to male screws of the fasteners  45  are provided between the two protrusions  32 . 
     The two protrusions  32  have columnar shapes protruding in the positive Y-axis direction from a surface of the slider body  31  on the positive Y-axis direction side. One of the two protrusions  32  is provided in a region of the slider body  31  on the positive Z-axis direction side, and the other is provided in a region of the slider body  31  on the negative Z-axis direction side. 
     The two protrusions  32  are provided with guides  34  that guide the wire  51  to the two holders  41 . The guide  34  is a groove extending in the Y-axis direction and the Z-axis direction. The guide  34  is provided in a central region of the protrusion  32  in the X-axis direction. The width of the guide  34  in the X-axis direction is large enough to dispose the wire  51  therein. In the present embodiment, the guide  34  is formed over the entire region of the protrusion  32  in the Y-axis direction. 
     The guide  34  is provided with an inclined part  35  in which the width of the groove is narrowed toward the two holders  41 . The inclined part  35  opens on a surface of the protrusion  32  opposite to a surface facing the holder  41 . 
     The two holders  41  are disposed on the slider body  31  and are configured to sandwich and hold the wire  51  therebetween. The holder  41  has a plate-like shape. In the present embodiment, an example in which the holder  41  is a rectangular plate member with corners cut off will be described. 
     The holder  41  is provided with an insertion hole  42  and a fixing hole  43 . 
     The insertion hole  42  is a through hole through which ends of the wire  51  are inserted. It is sufficient that the insertion hole  42  be provided in at least one of the two holders  41 . In the present embodiment, the insertion hole  42  is provided in a central region of the holder  41  in the Z-axis direction. 
     The fixing hole  43  is a through hole through which the fastener  45  is inserted. The fixing hole  43  is provided in both of the two holders  41 . In the present embodiment, the two fixing holes  43  are provided side by side in the Z-axis direction with the insertion hole  42  interposed therebetween. 
     The fasteners  45  fix the two holders  41  so that the two holders  41  are disposed on the slider body  31  and so that the wire  51  is held between the two holders  41 . In the present embodiment, an example in which the fastener  45  has a male screw will be described. 
     As illustrated in  FIG. 3 , the two spacers  47  each have a hole into which the fastener  45  is inserted. The spacers  47  are disposed between the slider body  31  and the two holders  41 . A desired value can be selected as the dimension of the spacer  47  in the Y-axis direction. 
     Next, a method of applying a desired tension to the wire  51  in the surgical instrument  1  having the above configuration will be described. 
     Note that forming the wire  51  in an annular shape in the following description includes not only holding both ends of one wire  51  to form the wire in an annular shape, but also holding respective ends of two wires  51  connected to the joint  11  or the like to form the wire in an annular shape. 
     As illustrated in  FIG. 2 , the wire  51  held by the slider  30  is guided from the inside of the shaft  10  to the slider  30  via the first guide pulley  25 , the second guide pulley  26 , and the third guide pulley  27 . 
     The ends of the wire  51  are held by each of the sliders  30  disposed in the driven grooves  21  on the positive direction side and the negative direction side of the X axis. As illustrated in  FIG. 5 , the wire  51  is disposed so as to pass through the guides  34  and the inclined parts  35  of the protrusions  32 . 
     The wire  51  having passed through the guide  34  and the inclined part  35  is disposed between the two holders  41  as illustrated in  FIG. 3 . The tip ends of the wire  51  pass through the insertion hole  42  of the holder  41  and are pulled out in the positive direction of the Y axis. At this time, the wire  51  is formed in an annular shape. In  FIG. 3 , only a part of the wire  51  held by the slider  30  is illustrated for ease of understanding. 
     The fasteners  45  are inserted into the fixing holes  43  of the holders  41 . Additionally, the fasteners  45  are screwed into the female screw holes  33  of the slider body  31 . The wire  51  disposed between the two holders  41  is disposed at a position avoiding the fasteners  45 . 
     The fasteners  45  are tightened into the female screw holes  33  while a force is applied to the tip ends of the wire  51  in a direction in which the wire  51  is pulled out from the insertion hole  42 . The magnitude of the applied force is such that a desired tension is applied to the annular wire  51 . 
     When the fasteners  45  are tightened into the female screw holes  33 , the wire  51  is held between the two holders  41 . Additionally, the two holders  41  are fixed to the slider body  31 . The wire  51  pulled out from the insertion hole  42  is processed not to interfere with the relative movement of the slider  30 . For example, the wire  51  is cut at the position of the insertion hole  42 . 
     With the surgical instrument  1  and the slider  30  having the above-described configurations, the ends of the wire  51  are inserted into the insertion hole  42  and pulled, whereby tension is applied to the annular wire  51 . By bringing the two holders  41  close to each other in a state where tension is applied to the annular wire  51 , the wire  51  can be held between the two holders  41 . Hence, a desired tension can be applied to the annular wire  51  without providing a mechanism for applying tension to the annular wire  51 , and a desired tension can be easily applied to the annular wire  51 . 
     By providing the protrusions  32  and the guides  34 , the positions of the two holders  41  relative to the slider body  31  can be easily stabilized. Further, by guiding the wire to the holder  41  using the guides  34  provided in the protrusions  32 , the position of the wire relative to the holders  41  can be easily stabilized. In particular, even if the slider body  31  causes relative movement in the Z-axis direction, the position of the wire relative to the holders  41  can be easily stabilized. 
     By providing the inclined part  35  in the guide  34 , the wire  51  can be disposed in the guide  34  easily. Additionally, it is easy to, curb an increase in stress acting on the contact portion between the wire  51  and the guide  34  when the slider body  31  causes relative movement in the Z-axis direction. 
     By providing the fasteners  45 , it is easy to perform the work of fixing the two holders  41  at desired positions of the slider body  31  and the work of fixing the two holders  41  with the wire  51  held between the two holders  41 . Additionally, both works can be performed simultaneously. 
     Note that the guide  34  may be a groove extending in the Y-axis direction and the Z-axis direction, or may be a guide  134  which is a through hole as illustrated in  FIG. 6 . The guide  134  is a through hole large enough to insert the wire  51 . 
     In  FIG. 6 , two guides  134  are provided to be spaced apart in the Y-axis direction in one protrusion  32 . The number of the guides  134  may be one, three, or more. 
     Note that the technical scope of the present disclosure is not limited to the above embodiment, and various modifications can be made without departing from the gist of the present disclosure. For example, in the present embodiment, an example in which the forceps  12  are disposed on the shaft  10  of the surgical instrument  1  has been described. Alternatively, any instrument used for treatment of a patient may be disposed on the shaft  10 .