Surgical tool with reduced actuation force

Abstract

A surgical tool includes a housing having a proximal end and a distal end, a yoke disposed within the housing between the proximal end and the distal end, a handle pivotably coupled to the housing, and a pivot assembly coupling the yoke to the housing. The pivot assembly includes a first link having a first end and a second end. The first end of the first link is rotatably coupled to the housing and the second end of the first link is rotatably coupled to a second link at a first end of the second link. The second link has a second end rotatably coupled to the yoke. The handle is coupled to the pivot assembly such that movement of the handle causes movement of the yoke.

Description

[0001] Related application data

[0002] This application is based upon and claims the benefit of priority under 35 U.S.C. § 119 to U.S. Provisional Application No. 63 / 154,372, filed on February 26, 2021, the entire contents of which are incorporated herein by reference. Technical Field

[0003] The present invention generally relates to a surgical tool having a reduced actuation force and, more particularly, to a surgical tool having a handle that requires a reduced actuation force to actuate a grasping instrument. Background Art

[0004] Surgical tools, such as laparoscopic surgical tools, that grasp and / or cut tissue by squeezing a handle can be actuated by moving a yoke. For example, surgeons often use handheld surgical tools for minimally invasive, robotic, and open surgeries. These surgical tools may include an end instrument assembly that is actuated by a handle squeezed by the surgeon. However, these tools typically require a significant amount of force to be applied to the handle to actuate the yoke, which in turn actuates a gripping assembly disposed at the end of the tool. Furthermore, the mechanism required to transmit the force from the handle to actuate the gripping assembly can be bulky and require a significant amount of space within the tool housing. Summary of the Invention

[0005] Embodiments of the present invention are directed to a surgical tool comprising: a housing having a proximal end and a distal end; a yoke disposed within the housing between the proximal end and the distal end; a handle pivotally coupled to the housing; and a pivot assembly coupling the yoke to the housing. The pivot assembly may include a first link having a first end and a second end, the first end of the first link being rotatably coupled to the housing, the second end of the first link being rotatably coupled to a second link at the first end of the second link, the second link having a second end rotatably coupled to the yoke. The handle may be coupled to the pivot assembly such that movement of the handle causes movement of the yoke.

[0006] In some embodiments, the surgical tool further includes a pivot pin pivotally coupling the second end of the first link to the first end of the second link, and a slot disposed within the handle, the slot configured to slidably receive the pivot pin.

[0007] In some embodiments, the slot includes a proximal end and a distal end, wherein the pivot pin is proximal to the proximal end of the slot when the handle is in the initial position and the pivot pin is proximal to the distal end of the slot when the handle is in the actuated position. The proximal end of the slot may be disposed above the distal end of the slot. The slot may be curved and extend from the proximal end to the distal end of the slot. The slot may curve downward toward the handle. The slot may curve upward toward the yoke.

[0008] In some embodiments, the pivot pin includes a ring that contacts an inner surface of the slot.The slot may include a low friction coating formed on an area of ​​the slot where the pivot pin contacts the slot.

[0009] In some embodiments, the pivot pin includes a first end and a second end, both of which are tapered.The pivot pin can be disposed through the handle, the first link, and the second link.

[0010] In some embodiments, the handle is coupled to the housing at a pivot point, and the pivot pin is disposed closer to the bottom of the handle than the pivot point. The pivot pin can be disposed between the first link and the second link. Pivoting the handle toward the proximal end of the housing can move the yoke distally.

[0011] In some embodiments, the handle has an initial position and an actuated position, the actuated position being a position of the handle when disposed proximal to the proximal end of the housing compared to when the handle is in the initial position.The handle may be coupled to one or both of the first link and the second link.

[0012] In some embodiments, the first link and the second link form an angle that increases as the yoke moves toward the distal end. The first link may be disposed proximally of the second link. The second end of the first link may be rotatably coupled to the first end of the second link via a pivot pin disposed through the handle. The second end of the second link may be rotatably coupled to the yoke via a second pivot pin disposed through the yoke. The first end of the first link may be rotatably coupled to the housing via a third pivot pin disposed through the housing.

[0013] In some embodiments, the surgical tool further comprises a grasping instrument disposed at the distal end of the housing, wherein movement of the handle causes movement of the yoke, and movement of the yoke causes actuation of the grasping instrument.

[0014] In some embodiments, the pivot assembly includes a motor coupled to the yoke and configured to move the yoke.The maximum length of the pivot assembly can be less than or equal to approximately 20 mm.

[0015] In some embodiments, the housing includes a longitudinal axis extending from a proximal end to a distal end, a handle configured to move along the longitudinal axis, and a yoke.

[0016] In some embodiments, the surgical tool further comprises an elongated shaft extending from a distal end of the housing, a grasping instrument disposed on the distal end of the elongated shaft, the grasping instrument coupled to the yoke such that movement of the yoke causes actuation of the grasping instrument.

[0017] Another embodiment of the present invention may provide a surgical tool having: a housing having a proximal end and a distal end; a yoke disposed within the housing; a handle having a top and a bottom, the handle pivotably coupled to the housing at a pivot point, the handle having a curved slot, wherein pivoting the handle causes the yoke to move proximally and distally; and a pivot assembly coupling the yoke to the housing, the pivot assembly comprising a first link having a first end and a second end, the first end of the first link rotatably coupled to the housing, the second end of the first link rotatably coupled to the second link at the first end of the second link via a pivot pin, the second link having a second end rotatably coupled to the yoke, and the pivot pin being disposed through the slot to couple the handle to the pivot assembly. The pivot pin may be disposed closer to the bottom of the handle than the pivot point.

[0018] Another embodiment of the present invention may provide a laparoscopic surgical tool comprising: a housing having a proximal end and a distal end, the housing including an axis extending from a portion of the housing near the proximal end to the distal end; a yoke arranged within the housing, the yoke being slidable relative to the housing; a handle having a top and a bottom, the handle being pivotally connected to the housing at a pivot point, the handle having a curved slot, wherein pivoting of the handle causes the yoke to move proximally and distally; a grasping instrument arranged at the distal end of the housing, the grasping instrument being constructed to actuate when the yoke moves; a gripping portion arranged closer to the distal end than the handle; and a pivot assembly connecting the yoke to the housing, the pivot assembly including a first link having a first end and a second end, the first end of the first link being rotatably connected to the housing, the second end of the first link being rotatably connected to the second link at the first end of the second link via a pivot pin, the second link having a second end rotatably connected to the yoke, the pivot pin being arranged closer to the bottom of the handle than the pivot point and being arranged to pass through the slot to connect the handle to the pivot assembly. The first link and the second link may form an angle and actuation of the handle may increase the angle to drive the yoke distally. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The foregoing summary, as well as the following detailed description of embodiments of surgical tools, will be better understood when read in conjunction with the appended drawings of exemplary embodiments. It should be understood, however, that the invention is not limited to the precise arrangements and instrumentalities shown.

[0020] Figure 1 is a partial cross-sectional view of a prior art open jaw surgical tool;

[0021] Figure 2 is a side view of some internal components of another prior art surgical tool;

[0022] Figure 3A is a side view of a laparoscopic surgical tool having a grasping instrument according to an exemplary embodiment of the present invention shown in an open configuration;

[0023] Figure 3B is shown in closed configuration Figure 3A Magnified view of the grasping instrument;

[0024] Figure 3C Is in open configuration Figure 3A Magnified view of the grasping instrument;

[0025] Figure 4A Shown in its initial position with the housing and handle removed for demonstration purposes Figure 3A A partial side view of a pivot assembly of a surgical tool;

[0026] Figure 4B is shown in the actuated position Figure 4A A partial side view of the pivot assembly;

[0027] Figure 5 It is taken along line A-A' Figure 4A a cross-sectional front view of an exemplary pivot assembly;

[0028] Figure 6A yes Figure 4A Schematic diagram of an exemplary pivot pin of a surgical tool;

[0029] Figure 6B yes Figure 4A Schematic diagram of an alternative exemplary pivot pin for a surgical tool;

[0030] Figure 7 It is around Figure 4A A perspective view of an exemplary ring of a pivot pin arrangement for a surgical tool;

[0031] Figure 8 is a diagram showing an exemplary low friction coating applied to a slot that receives a pivot pin. Figure 4A a perspective view of the pivot assembly; and

[0032] Figure 9 is a graph illustrating the grip force required for actuation over the stroke lengths of an exemplary embodiment of the present invention and a prior art handle. DETAILED DESCRIPTION

[0033] Reference Figures 1 to 2 Existing surgical tools used for laparoscopic surgery include a handle that actuates a yoke based on movement to perform a specific function, such as actuating a grasping instrument. The grasping instrument may be disposed at the end of the surgical tool. These surgical tools may be handheld tools configured to grasp and cut tissue.

[0034] like Figure 1As shown, a known surgical tool 1 may include a handle 3, a coupling member 5, a pivot point 7, a grip 8, and a slider 9. In some embodiments, the surgical tool 1 is configured to grasp and / or cut tissue using the handle 3 and a grasping instrument (not shown). In some embodiments, the grip 8 is configured to be held in the hand of a user (e.g., a surgeon or other operator), and the handle 3 is movable relative to the grip 8. The handle 3 may be coupled to the pivot point 7 via the coupling member 5. The handle 3 may be actuated by the user and configured to pivot about the pivot point 7 to move the slider 9. For example, the handle 3 may be coupled to the slider 9 and actuated by the user such that moving the handle 3 causes movement of the slider 9. The movement of the slider 9 may actuate a grasping instrument disposed at the distal end of the surgical tool 1. The grasping instrument may be configured to open and close by actuating the handle 3 relative to the grip 8. In some embodiments, the gripping force required to fully actuate the handle 3 is large. For example, the gripping force required to fully actuate the handle 3 and move the slide 9 may be greater than 30 Newtons (N).

[0035] like Figure 2 As shown, a known surgical tool 11 may include a housing 31, a handle 13, a first link 23, a second link 19, a third link 29, a yoke 17, and a pivot pin 21. The handle 13 may be coupled to the third link 29, which may be configured to actuate the first link 23 via a cam 27. The first link 23 may be coupled to the second link 19 via a pivot pin 21, and the first link 23 may be further coupled to the yoke 17. Similar to the surgical tool 1, the surgical tool 11 may be a handheld surgical tool configured to actuate a grasping instrument. For example, during use, a user may apply a grasping force to the handle 13. The grasping force on the handle 13 is then converted into movement of a grasping instrument disposed at the distal end of the surgical tool 11. In some embodiments, the surgical tool 11 is configured to grasp and / or cut tissue using the handle 13 and the grasping instrument. In use, actuation of the handle 13 causes the third link 29 to move the second link 19, which causes movement of the first link 23, thereby moving the yoke 17. The yoke 17 can be attached to a grasping instrument (not shown) or another tool disposed at the distal end of the shaft 25. The gripping force required to fully actuate the handle 13 and move the yoke 17 may be greater than 30 N. In some embodiments, the first link 23, the second link 19, and the third link 29 require a significant amount of space within the housing 31.

[0036] Reference Figures 3A to 8, shows a tool 100 with an improved pivot assembly for converting a gripping force applied to a handle into actuation of an end instrument (such as the grasping instrument shown). In use, the tool 100 can be used to actuate an instrument disposed on the tool. The improved pivot assembly of the tool 100 can better convert a gripping force applied to the handle into actuation of the instrument. For example, compared to known surgical tools, the improved pivot assembly can require a reduced gripping force on the handle of the tool 100 to cause actuation of the instrument. The tool 100 can be configured to better convert movement of the handle into movement of the instrument. In some embodiments, the tool 100 is configured to convert squeezing (e.g., pivoting) of the handle into axial movement of a yoke coupled to the instrument. Movement of the yoke can cause actuation of the instrument.

[0037] In some embodiments, tool 100 is a surgical tool for grasping, manipulating, and cutting tissue. For example, tool 100 can be a surgical energy device having a grasping instrument configured to grasp, manipulate, and cut / cauterize tissue. The grasping instrument can be coupled to an elongated, narrow shaft extending from the housing of tool 100 and can be configured to be inserted into a patient while a substantial portion of the housing of tool 100 remains external to the patient. The shaft with open jaws can be inserted into the patient and the elongated shaft can include a grasping instrument configured to open and close to grasp tissue.

[0038] In some embodiments, the tool 100 is configured to grasp and / or cut tissue arranged in a small, confined area. For example, when used during surgery, the movement of the user's hand on the handle can be converted into corresponding movement of the grasping instrument. In some embodiments, the tool 100 is a laparoscopic tool for grasping and cutting tissue during laparoscopic surgery. However, the tool 100 can be a surgical tool for open surgery, robotic surgery, or minimally invasive surgery. The tool 100 can also be used for non-surgical applications. For example, the tool 100 can be used in applications such as automotive, construction, cleaning, manufacturing, non-surgical medical surgery, or any other desired application. The tool 100 can be used in any application that requires converting the force applied to the handle into the actuation of the instrument. In some embodiments, the tool 100 is configured to be handheld by the user.

[0039] Reference Figures 3A to 3CTool 100 may include a housing 101, a handle 102, a shaft 153, a grip 155, and an instrument assembly 171. Handle 102 can be actuated by a user to actuate instrument assembly 171. For example, handle 102 may have an initial position and an actuated position. The actuated position may be a position in which handle 102 is moved relative to grip 155, such that handle 102 is closer to grip 155, compared to when handle 102 is in the initial position. During use, a user can hold tool 100 by placing grip 155 in the palm of their hand and placing their thumb around grip 155. The user's fingers can wrap around handle 102 and squeeze their hand, with their fingers toward their palm and thumb, to pull handle 102 toward grip 155 to actuate handle 102. Actuation of handle 102 can actuate instrument assembly 171. In some embodiments, handle 102 includes a loop, and during use, the user's fingers are positioned through the loop. However, the handle 102 may not include a ring actuated by one or more fingers, an open ring, a ring for each finger, a lever, or a trigger.

[0040] In some embodiments, handle 102 is forced to an initial position and must be moved to an actuated position by a user or a motor. Moving handle 102 to the actuated position can cause actuation of instrument assembly 171. In some embodiments, instrument assembly 171 is a grasping / opening jaw instrument and includes a closing ( Figure 3B ) and open ( Figure 3C )structure.

[0041] Reference Figure 3A , the housing 101 can include a proximal end 105 and a distal end 103. In some embodiments, the housing includes a longitudinal axis 110 extending from the proximal end 105 through the distal end 103 and along the shaft 153. The shaft 153 can extend from the distal end 103 of the housing 101, and the instrument assembly 171 can be located at the distal end of the shaft 153. In some embodiments, the instrument assembly 171 is a grasping instrument. For example, the instrument assembly 171 can include jaws 173 and a blade 172. The jaws 173 can be in a closed configuration ( Figure 3B ) and open constructs ( Figure 3C) move between the jaws 173 and the blade 172. The blade 172 can be configured to cut and / or cauterize tissue disposed within the instrument assembly 171. For example, the jaws 173 can be configured to grasp tissue or a blood vessel, and the blade 172 can be configured to cut and / or cauterize tissue or a blood vessel. The blade 172 can be configured to receive an electrical current to heat it and thereby cauterize tissue. In some embodiments, the instrument assembly 171 includes scissors, forceps, a needle driver, a retractor, a syringe, a tube for aspiration and / or irrigation, a blade / knife, and / or a cauterizing or energy device. However, the instrument assembly 171 can be any desired instrument. For example, the instrument assembly 171 can be an instrument used in medical, automotive, construction, cleaning, manufacturing, or any other desired application.

[0042] like Figures 4A to 8 As shown, tool 100 can include a handle 102, a yoke 106, and a pivot assembly 115. Yoke 106 and pivot assembly 115 can be disposed within housing 101. For example, yoke 106 and pivot assembly 115 can be coupled to housing 101. In some embodiments, handle 102 is coupled to housing 101. Handle 102 can additionally be coupled to housing 101 and yoke 106 via pivot assembly 115. In some embodiments, yoke 106 is disposed along longitudinal axis 110 between proximal end 105 and distal end 103. Yoke 106 can be disposed along longitudinal axis 110 and axially aligned with shaft 153. In some embodiments, yoke 106 is coupled to instrument assembly 171 via shaft 153 such that movement of yoke 106 along longitudinal axis 110 causes actuation of instrument assembly 171.

[0043] In some embodiments, yoke 106 is coupled to housing 101 to allow yoke 106 to move axially along longitudinal axis 110. For example, yoke 106 can be slidingly coupled to housing 101 such that yoke 106 is configured to move along longitudinal axis 110 from proximal end 105 to distal end 103. Yoke 106 can also be configured to move axially in alignment with shaft 153. In some embodiments, yoke 106 is coupled to housing 101 along a track to allow yoke 106 to move axially along longitudinal axis 110. However, yoke 106 can be coupled to housing 101 via other methods, such as via magnets, rails, wheels, force-applying elements, springs, tension members, or any other desired method. Movement of yoke 106 along longitudinal axis 110 can cause actuation of instrument assembly 171.

[0044] In some embodiments, the yoke 106 includes a protrusion 109 and the housing 101 includes an inner rail 111 and an outer rail (not shown). The rail 111 can be configured to receive the protrusion 109 so that the yoke 106 can slide relative to the housing 101. For example, the yoke 106 can slide along the inner rail 111 and / or the outer rail so that the yoke 106 can slide relative to the housing 101 along the longitudinal axis 110. In some embodiments, the protrusion 109 is configured to rest on the inner rail 111 and / or the outer rail so that the protrusion 109 and the yoke 106 can slide along one or more of the inner rail 111 or the outer rail. In some embodiments, the inner rail 111 includes a stop 113 to prevent the yoke 106 from moving too far back toward the proximal end 105. The inner rail 111 and / or the outer rail can be configured to allow the yoke 106 to move from the distal end 103 to the proximal end 105 along the longitudinal axis 110.

[0045] In some embodiments, the handle 102 is coupled to and fixed to the housing 101. The handle 102 can be configured to move from an initial position ( Figure 4A ) moves to the actuated position ( Figure 4B ). The actuated position may be a position when the handle 102 is closer to the proximal end 105, as compared to when the handle 102 is in the initial position. In some embodiments, the initial position of the handle 102 is a position when the handle 102 has not been actuated by the user. The initial position of the handle 102 may be a position when the handle 102 is stationary and the yoke 106 is arranged closer to the proximal end 105, as compared to when the handle 102 is actuated. In some embodiments, moving the handle 102 from the initial position ( Figure 4A ) moves to the actuated position ( Figure 4B ) The force required to move the handle 102 from the initial position to the actuated position is approximately 30N or less. For example, the force required to move the handle 102 from the initial position to the actuated position can be less than 35N. In some embodiments, the axial force required to move the handle 102 from the initial position to the actuated position is approximately 150N or less. The axial force can be a force applied along the longitudinal axis 110. For example, the axial force can be a force that drives the yoke 106 from the proximal end 105 to the distal end 103. In some embodiments, the axial force drives the yoke 106 along the longitudinal axis 110. In other words, the axial force is a force that is transmitted through the shaft 153 to actuate the instrument assembly 171, such as the jaws 173. In some embodiments, when the axial force is transmitted to the jaws 173 via the yoke 106, the jaws 173 rotate about a pivot point connected to the shaft 153, causing the jaws 173 to close. The direction of the axial force is consistent with the direction of the shaft 153.

[0046] Reference Figure 3A as well as Figures 4A to 4B, the handle 102 can be pivotally coupled to the housing 101. In some embodiments, the handle 102 is coupled to the housing 101 via a pivot point 108. For example, the handle 102 can be configured to rotate or pivot about the pivot point 108. In some embodiments, when the handle 102 moves from the initial position to the actuated position, the handle 102 pivots about the pivot point 108 toward the distal end 103, and the yoke 106 is driven forward toward the distal end 103 of the housing 101 via the pivot assembly 115.

[0047] In some embodiments, actuation of yoke 106 causes actuation of instrument assembly 171. For example, instrument assembly 171 can be coupled to yoke 106 via shaft 153. In some embodiments, proximally and distally actuating yoke 106 causes jaws 173 of instrument assembly 171 to open and close. For example, moving handle 102 from an initial position to an actuated position can cause yoke 106 to be actuated toward distal end 103, thereby causing jaws 173 to close. Movement of handle 102 from the actuated position back to the initial position can cause yoke 106 to move proximally, causing jaws 173 to open. However, instrument assembly 171 can be any desired instrument such that movement of handle 102 and yoke 106 causes actuation of instrument assembly 171.

[0048] In some embodiments, the handle 102 and the yoke 106 can each have a stroke length. The stroke length can be the length of movement required to fully actuate the handle 102 or the full length of movement of the yoke 106. In some embodiments, the stroke length of the handle 102 can be between approximately 5 mm and approximately 25 mm. In a preferred embodiment, the stroke length of the handle 102 is between 9 mm and 14 mm. In some embodiments, the stroke length of the yoke 106 can be between approximately 1 mm and approximately 20 mm. In a preferred embodiment, the stroke length of the yoke 106 is between approximately 3 mm and approximately 5 mm.

[0049] In some embodiments, the handle 102 is coupled to the yoke 106 via a pivot assembly 115. The pivot assembly 115 can be configured to drive the yoke 106 proximally and distally when the handle 102 is moved. The pivot assembly 115 can be sized and shaped to be disposed entirely within the housing 101. For example, the pivot assembly 115 may not extend into the grip 155 and may have a maximum length of less than or equal to 20 mm.

[0050] Reference Figures 4A to 4BThe pivot assembly 115 may include a first link 114 and a second link 118. The first link 114 may have a first end 114a and a second end 114b, and the second link 118 may have a first end 118a and a second end 118b. The first end 114a of the first link 114 may be coupled to the housing 101. In some embodiments, the first end 114a may be rotatably coupled to the housing 101. The first end 114a may be coupled to the housing 101 via a first pivot pin 116. The first end 114a may be pivotally coupled to the housing 101 such that the first end 114a is fixed in position relative to the housing 101 and is configured to pivot only about the first pivot pin 116. The second end 114b of the first link 114 may be coupled to the first end 118a of the second link 118. In some embodiments, the second end 114b may be pivotally coupled to the first end 118a via a second pivot pin 120. The second end 118b of the second link 118 can be pivotally coupled to the yoke 106 at the third pivot pin 112. In some embodiments, the second pivot pin 120 and the third pivot pin 112 are configured to move relative to the housing 101. For example, the third pivot pin 112 and the second pivot pin 120 can be configured to move proximally and distally and away from and toward the handle 102. The second pivot pin 120 and the third pivot pin 112 can move relative to the housing 101, causing the second end 114a of the first link 114 and the first and second ends 118a, 118b of the second link 118 to move relative to the housing 101.

[0051] In some embodiments, the first pivot pin 116, the second pivot pin 120, and the third pivot pin 112 all extend through the housing 101. The third pivot pin 112 can extend through both the yoke 106 and the housing 101. For example, the third pivot pin 112 can extend across the width of the yoke 106 and the housing 101. In some embodiments, the second pivot pin 120 is disposed between the first pivot pin 116 and the third pivot pin 112.

[0052] Reference Figure 3A and Figure 4A, the second pivot pin 120 can be positioned lower than the pivot point 108. For example, the second pivot pin 120 can be positioned closer to the handle 102 and farther from the yoke 106 than the pivot point 108. In addition, the second pivot pin 120 can be positioned closer to the location where a user contacts the handle 102 compared to the first pivot pin 116 and the third pivot pin 112. In some embodiments, the handle 102 includes a top 119 and a bottom 117. The second pivot pin 120 can be positioned closer to the bottom 117 than the pivot point 108. For example, the pivot point 108 can be positioned higher than the second pivot pin 120, resulting in the second pivot pin 120 being positioned closer to the bottom 117 of the handle 102. The positioning of the pivot point 108 higher than the second pivot pin 120 can result in the distance between the grip force applied to the handle 102 and the pivot point 108 being greater than the distance between the grip force applied to the handle 102 and the second pivot pin 120. In some embodiments, the pivot point 108 overlaps the yoke 106. For example, the pivot point 108 can be adjacent to the yoke 106 such that the pivot point 108 overlaps the yoke 106 and the second pivot pin 120 can not overlap.

[0053] In some embodiments, positioning the pivot point 108 above the second pivot pin 120 results in a reduced gripping force required to actuate the handle 102. In effect, positioning the pivot point 108 above the second pivot pin 120 changes the direction of movement of the handle 102 compared to existing conventional surgical tools, thereby reducing the force required to actuate the handle 102. In some embodiments, the first pivot pin 116, the second pivot pin 120, and the third pivot pin 112 are disposed below the pivot point 108.

[0054] In some embodiments, the first connecting rod 114 and the second connecting rod 118 each have a length greater than their width. In some embodiments, the first connecting rod 114 and the second connecting rod 118 have the same length and width. However, the first connecting rod 114 may have a different length and width from the second connecting rod 118. The first connecting rod 114 may have a length of approximately 72 mm and a width of approximately 23 mm. However, the first connecting rod 114 may have a length between approximately 25 mm and approximately 100 mm and a width between approximately 10 mm and 50 mm. The second connecting rod 118 may have a length of approximately 72 mm and a width of approximately 23 mm. However, the second connecting rod 118 may have a length between approximately 25 mm and approximately 100 mm and a width between approximately 10 mm and 50 mm. In some embodiments, the first connecting rod 114 and / or the second connecting rod 118 are made of polycarbonate or polyacetal. The first link 114 and the second link 118 may be sized and shaped to fit within a small, confined area of ​​the housing 101 , thereby reducing the amount of space required for the pivot assembly 115 .

[0055] In some embodiments, the pivot assembly 115 includes a first pivot pin 116, a second pivot pin 120, and a third pivot pin 112. The first pivot pin 116 can have a diameter of approximately 4 mm, the second pivot pin 120 can have a diameter of approximately 4 mm, and the third pivot pin 112 can have a diameter of approximately 4 mm. The first pivot pin 116, the second pivot pin 120, and the third pivot pin 112 can have a length of approximately 16 mm. However, the length of the first pivot pin 116, the second pivot pin 120, and the third pivot pin 112 can be between approximately 5 mm and approximately 25 mm. The first pivot pin 116, the second pivot pin 120, and the third pivot pin 112 can have a diameter of approximately 4 mm. However, the first pivot pin 116, the second pivot pin 120, and the third pivot pin 112 can have a diameter of between approximately 1 mm and approximately 10 mm. In some embodiments, the first pivot pin 116, the second pivot pin 120, and the third pivot pin 112 each have a different diameter. The first pivot pin 116, the second pivot pin 120, and the third pivot pin 112 can each be received through the housing 101 via an aperture disposed within the housing 101. In some embodiments, the first pivot pin 116, the second pivot pin 120, and the third pivot pin 112 each extend across a substantial width of the housing 101.

[0056] Reference Figures 4A to 5 , the second pivot pin 120 can be arranged to pass through the second end 114b of the first link 114 and the first end 118a of the second link 118. When coupled together via the second pivot pin 120, the first link 114 and the second link 118 can form an angle α. In some embodiments, the first link 114 can be arranged at an angle α relative to the second link 118. Movement of the second pivot pin 120 can cause movement of the first link 114 and the second link 118, which can increase or decrease the angle α. For example, upward movement of the second pivot pin 120 toward the yoke 106 can cause the angle α to increase, while downward movement of the second pivot pin 120 toward the handle 102 can cause the angle α to decrease.

[0057] In some embodiments, handle 102 includes a slot 122. In some embodiments, a second pivot pin 120 is disposed through slot 122, thereby coupling handle 102 to pivot assembly 115. Slot 122 can receive second pivot pin 120 in a manner that enables second pivot pin 120 to move within slot 122. For example, second pivot pin 120 can slide within slot 122. Second pivot pin 120 can be configured to slide proximally and distally within slot 122. In some embodiments, second pivot pin 120 disposed within slot 122 acts as a point load through which a gripping force applied to handle 102 is converted into axial movement of yoke 106, thereby actuating instrument assembly 171. For example, a gripping force applied to handle 102 to move handle 102 from an initial position to an actuated position can cause second pivot pin 120 to be driven distally within slot 122. Slot 122 can be shaped such that when second pivot pin 120 is driven distally within slot 122, second pivot pin 120 is driven upward toward yoke 106, which drives first link 114 and yoke 106 distally. The distally driven yoke 106 can cause actuation of instrument assembly 171.

[0058] Reference Figures 4A to 4B as well as Figure 7 , the shape of groove 122 can be curved and oval. However, groove 122 can be rectangular, triangular, polygonal or any other desired shape. In one embodiment, groove 122 is bent downwards towards handle 102. In some embodiments, groove 122 is bent downwards towards handle 102, causing force efficiency to increase when handle 102 approaches the actuated position. For example, when groove 122 is bent downwards, when the user actuates handle 102, the required gripping force decreases as handle 102 moves toward the actuated position. Compared with groove 122 not being bent downwards, groove 122 is bent downwards towards handle 102, which can cause the gripping force required for handle 102 to be maintained at the actuated position to decrease. In an alternative embodiment, groove 122 is bent upwards towards yoke 106. In some embodiments, groove 122 is bent upwards towards yoke 106, causing force efficiency to increase when handle 102 approaches the initial position. For example, when the slot 122 curves upward, when a user actuates the handle 102, the grip force required to initially actuate the handle 102 is reduced compared to the grip force required to maintain the handle 102 in the actuated position.

[0059] The slot 122 can have a proximal end 122a and a distal end 122b. In some embodiments, the proximal end 122a of the slot 122 can be arranged above the distal end 122b of the slot 122, such that the proximal end 122a is arranged closer to the yoke 106 than the distal end 122b. In some embodiments, the slot 122 is curved and has a radius of curvature R. In some embodiments, when the slot 122 curves downward toward the handle 102, the greater the radius of curvature R is, the less grip force required on the handle 102 to hold the handle 102 in an actuated position due to the curved shape of the slot 122. For example, a slot 122 having a downward shape and a radius of curvature R of approximately 20 mm can result in a force reduction of approximately 7.5% compared to a slot 122 having a radius of curvature R of approximately 5 mm. In some embodiments, a very large radius of curvature R of the slot 122 can result in a relatively large gripping force to move the handle 102 out of the initial position, but very low force to move the handle 102 to the actuated position and to maintain the handle 102 in the actuated position.

[0060] In some embodiments, the slot 122 is sized and shaped such that the second pivot pin 120 can slide within the slot 122. For example, the second pivot pin 120 can be configured to slide between a proximal end 122a and a distal end 122b. In some embodiments, the second pivot pin 120 can include an end 120a that can be sized to prevent the second pivot pin 120 from accidentally exiting the slot 122. For example, the end 120a of the second pivot pin 120 can be sized to have a diameter that is greater than the width of the slot 122 to prevent the second pivot pin 120 from accidentally exiting the slot 122.

[0061] Reference Figures 4A to 4B , actuation of the handle 102 may cause the second pivot pin 120 to slide within the slot 122. For example, the handle 102 may be moved from its initial position ( Figure 4A ) to the actuated position ( Figure 4B ) can cause the second pivot pin 120 to slide from the proximal end 122a to the distal end 122b of the slot 122. In some embodiments, when the handle 102 is in the initial position, the second pivot pin 120 is disposed proximal to the proximal end 122a of the slot 122, and when the handle 102 is in the actuated position, the second pivot pin 120 is disposed proximal to the distal end 122b of the slot 122.

[0062] In some embodiments, movement of the handle 102 from the initial position to the actuated position causes the angle α to increase due to the sliding of the second pivot pin 120 within the slot 122. For example, when the handle 102 is in the initial position, the angle α may be 110°, and when the handle 102 is in the actuated position, the angle α may be 160°. When the angle α increases due to the movement of the second pivot pin 120 within the slot 122 of the handle 102, the second link 118 rotates about the third pivot pin 112 and drives the third pivot pin 112 toward the distal end 103, thereby pushing / actuating the yoke 106 toward the distal end 103. Conversely, decreasing the angle α causes the second link 118 and the third pivot pin 112 to move toward the proximal end 105, thereby pulling the yoke 106 toward the proximal end 105. The increase or decrease in angle α is caused by the movement of the second pivot pin 120 within the slot 122, which is caused by the movement of the handle 102. In some embodiments, first link 114 and second link 118 pivot about second pivot pin 120. In some embodiments, movement of second pivot pin 120 causes yoke 106 to translate proximally and distally, thereby causing actuation of instrument assembly 171. For example, movement of handle 102 from an initial position to an actuated position can cause second pivot pin 120 to move toward yoke 106, increasing angle α and driving yoke 106 toward distal end 103. Driving yoke 106 toward distal end 103 can actuate instrument assembly 171, which can be a grasping instrument, causing jaws 173 to close.

[0063] In practice, when handle 102 moves from the initial position to the actuated position, handle 102 pivots about pivot point 108 and second pivot pin 120. Pivoting handle 102 about second pivot pin 120 causes second pivot pin 120 to slide distally within slot 122 and move upward toward yoke 106, which increases angle α and pushes second link 118 toward distal end 103. Increasing angle α and pushing second link 118 toward distal end 103 pushes third pivot pin 112 and drives yoke 106 forward toward distal end 103. In some embodiments, driving yoke 106 toward distal end 103 causes actuation of instrument assembly 171, such as a grasping instrument. In other words, when handle 102 moves from the initial position to the actuated position, yoke 106 is driven toward distal end 103 via pivot assembly 115, which actuates instrument assembly 171.

[0064] In some embodiments, tool 100 is used in conjunction with a robotic surgical device for robotic surgery and includes a motor. The motor can be configured to drive second pivot pin 120. For example, instead of handle 102, the motor can be used to drive second pivot pin 120 upward and toward yoke 106, thereby driving yoke 106 toward distal end 103. The motor can be coupled to the robotic surgical device and can be controlled by a user. In some embodiments, the user can activate the motor, which causes movement of second pivot pin 120, thereby driving yoke 106 toward distal end 103 and actuating instrument assembly 171.

[0065] Reference Figure 6A and Figure 6B The second pivot pin 120 may have a first end 124a and a second end 124b. The first end 124a and the second end 124b may be the portions of the second pivot pin 120 that contact the slot 122. In some embodiments, the first end 124a and the second end 124b are flat and non-tapered. However, the non-tapered first end 124a and the second end 124b may cause significant friction between the second pivot pin 120 and the slot 122. In some embodiments, to reduce the amount of friction between the second pivot pin 120 and the slot 122, the second pivot pin 120 may include a tapered first end 124a' and a second end 124b'. The tapered first end 124a' and the second end 124b' reduce the vertical force felt by the slot 122 on the first end 124a' and the second end 124b'. Furthermore, tapering the first and second ends 124a', 124b' can reduce friction between the second pivot pin 120 and the slot 122 as the second pivot pin 120 slides within the slot 122. In some embodiments, the second pivot pin 120 can taper from a diameter of approximately 4 mm to a diameter of approximately 2 mm.

[0066] Reference Figure 7 , the second pivot pin 120 may include one or more rings 128. The rings 128 may be low-friction rings arranged around the circumference of the second pivot pin 120 to reduce the amount of friction between the groove 122 and the second pivot pin 120. In some embodiments, the second pivot pin 120 may include the rings 128 near the first end 124a or 124a' and / or near the second end 124b or 124b'. However, the second pivot pin 120 may include the rings 128 at any location. For example, the second pivot pin 120 may include the rings 128 across the entire outer surface or may include the rings 128 only where the second pivot pin 120 contacts the groove 122. In some embodiments, one or more of the first pivot pin 116, the second pivot pin 120, and the third pivot pin 112 include one or more rings 128.

[0067] Reference Figure 8Groove 122 may include a coating 130, which may be a low-friction coating. Coating 130 may be applied to the interior surface of groove 122. For example, coating 130 may be applied to the portion of groove 122 that contacts second pivot pin 120. Coating 130 may be applied to groove 122 during manufacture of tool 100. Coating 130 may be a substance applied to the interior of groove 122 or a material bonded to the interior of groove 122. For example, coating 130 may be a low-friction primer applied to the interior of groove 122, or coating 130 may be a strip of low-friction material bonded to the interior of groove 122, such as by an adhesive. Coating 130 may be PTFE. Coating 130 may be applied to a portion of groove 122 or to the entire groove 122. For example, coating 130 may be dispersed within groove 122 or may cover the entire groove 122. In some embodiments, coating 130 is applied anywhere on the contact surfaces of first pivot pin 116, second pivot pin 120, and / or third pivot pin 112.

[0068] Reference Figure 9 , provides a graph illustrating the gripping force required to achieve the desired stroke length. For the inventive sample, Figure 9 The graph in FIG shows that the handle 102 is Figure 4A The initial position shown in the figure (corresponding to Figure 9 Position 200) transitions to Figure 4B The actuation position shown (corresponding to Figure 9 The graph shows how gripping force (N) varies with stroke length (mm) during the process of moving from position 205 in the middle of the tool (Fig. 2). As shown in the graph, tool 100 requires less gripping force to achieve the desired stroke compared to other prior art tools, such as Conventional Technology 1 and Conventional Technology 2. For example, tool 100 allows for a maximum gripping force of less than 35N to actuate handle 102, and a stroke length of handle 102 of less than 14mm. This results in an approximately 10% reduction in the maximum gripping force required to actuate handle 102 compared to other prior art tools.

[0069] In fact, the lower the grip force and the shorter the stroke length, the less fatigue the user will experience when using the tool 100. In addition, if the maximum grip force required to actuate the handle 102 is greater than 35N, users with small hands or weak hands may not be able to actuate the handle 102. However, a handle 102 with too short a stroke length will make it difficult to utilize the tool 100 and perform delicate operations using the instrument assembly 171 in confined spaces. Therefore, a handle 102 with a maximum grip force of less than 35N and a stroke length of less than 14mm allows the user to maintain a grip on the handle 102 to operate the tool 100, reducing fatigue compared to other prior art tools such as Conventional Technology 1 and Conventional Technology 2. Figure 9 The forces measured in the graph of occur when instrument assembly 171 is not grasping tissue or an object.

[0070] Those skilled in the art will appreciate that changes may be made to the exemplary embodiments shown and described above without departing from the broad inventive concept thereof. Therefore, it will be understood that the invention is not limited to the exemplary embodiments shown and described, but is intended to cover variations within the spirit and scope of the invention as defined by the claims. For example, certain features of the exemplary embodiments may or may not be part of the claimed invention, and various features of the disclosed embodiments may be combined. The words "near," "far," "above," and "below" indicate directions in the accompanying drawings to which reference is made. Unless otherwise specified herein, the terms "a" and "the" are not limited to one element, but are to be understood to mean "at least one."

[0071] It should be understood that at least some of the drawings and descriptions of the present invention have been simplified to focus on elements relevant to a clear understanding of the present invention, while other elements that may also form part of the present invention and that will be understood by those of ordinary skill in the art have been eliminated for the purpose of clarity. However, because these elements are well known in the art and because they do not necessarily contribute to a better understanding of the present invention, a description of these elements is not provided herein.

Claims

1. A surgical tool comprising: a housing having a proximal end and a distal end; a yoke disposed within the housing between the proximal end and the distal end; a handle pivotally coupled to the housing; a pivot assembly coupling the yoke to the housing, the pivot assembly comprising: a first link having a first end and a second end, the first end of the first link being rotatably coupled to the housing; a second link having a first end and a second end, the second end of the second link being rotatably coupled to the yoke, wherein the second end of the first link is rotatably coupled to the first end of the second link; a pivot pin pivotally coupling the second end of the first link to the first end of the second link, the pivot pin being disposed through the handle, the first link, and the second link; and a slot disposed within the handle, the slot being configured to slidably receive the pivot pin, wherein the handle is coupled to the pivot assembly such that movement of the handle causes movement of the yoke.

2. The surgical tool according to claim 1, wherein: The slot includes a proximal end and a distal end. When the handle is in the initial position, the pivot pin is proximate to the proximal end of the slot. When the handle is in the actuated position, the pivot pin is proximate to the distal end of the slot.

3. The surgical tool according to claim 2, wherein: The proximal end of the slot is disposed above the distal end of the slot.

4. The surgical tool according to claim 2, wherein: The slot is curved and extends from a proximal end of the slot to a distal end of the slot.

5. The surgical tool according to claim 2, wherein: The slot curves downwardly toward the handle.

6. The surgical tool according to claim 2, wherein: The slot curves upwardly toward the yoke.

7. The surgical tool according to claim 1, wherein: The pivot pin includes a ring that contacts an inner surface of the slot.

8. The surgical tool according to claim 1, wherein: The slot includes a low friction coating formed on an area of ​​the slot where the pivot pin contacts the slot.

9. The surgical tool according to claim 1, wherein: The pivot pin includes a first end and a second end, and both the first end and the second end of the pivot pin are tapered.

10. The surgical tool according to claim 1, wherein: The handle is coupled to the housing at a pivot point, and the pivot pin is disposed closer to a bottom of the handle than the pivot point.

11. The surgical tool according to claim 1, wherein: The pivot pin is disposed between the first link and the second link.

12. The surgical tool according to claim 1, wherein: The first link and the second link form an angle that increases as the yoke moves toward the distal end.

13. The surgical tool according to claim 1, further comprising: A grasping instrument is disposed at the distal end of the housing, wherein movement of the handle causes movement of the yoke, which causes actuation of the grasping instrument.

14. The surgical tool according to claim 1, wherein: The first link is arranged on a proximal side of the second link.

15. The surgical tool according to claim 1, wherein: The pivot assembly includes a motor coupled to the yoke and configured to move the yoke.

16. The surgical tool according to claim 1, wherein: The handle is coupled to one or both of the first link and the second link.

17. The surgical tool according to claim 1, wherein: The second end of the first link is rotatably coupled to the first end of the second link via a pivot pin disposed through the handle.

18. The surgical tool according to claim 1, wherein: The second end of the second link is rotatably coupled to the yoke via a second pivot pin disposed through the yoke.

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