Forceps head driving assembly and electrosurgical instrument

Abstract

The utility model relates to a forceps head driving assembly and an electrosurgical instrument, and is applied to the field of electrosurgical instruments. The clamping mechanism comprises a moving part, a connecting part, a driving part and an elastic part, the moving part can move relative to the shell in the first direction, the moving part comprises an opening position, a closing position and a clamping position, a sliding groove is formed in the moving part, and the sliding groove extends in the first direction; the connecting piece is installed in the sliding groove in a sliding mode and comprises an initial position and a tail position which are sequentially arranged relative to the shell. The connecting piece further comprises an installation part used for installing the movable tong head. The driving part is connected to the moving part to drive the moving part to move in the first direction. The elastic piece is installed in the sliding groove, arranged on the periphery of the connecting piece in a sleeving mode and connected between the connecting piece and the groove wall of the sliding groove in an abutting mode. Opening and closing control over the movable tong head is achieved through movement of the moving part in the first direction, so that an operator can rapidly switch the opening and closing states of the tong head through driving of the driving part on the moving part in the using process, and convenience of opening and closing control is improved.

Description

Technical Field

[0001] The present application relates to the technical field of electrosurgical instruments, and in particular to a forceps drive assembly and an electrosurgical instrument. Background Art

[0002] Electrosurgical closed cutting instruments and their end effectors suitable for minimally invasive surgery are instruments that can enter the human body through tiny wounds and cut and coagulate vascular tissue. They are also one of the instruments widely used in minimally invasive surgery, mainly used for cutting, transection and coagulation of tissues in open or endoscopic surgery in abdominal surgery, gynecology, pediatrics and thoracic surgery.

[0003] However, the internal structure of the electrosurgical closed cutting instrument is complex, and the operator cannot independently control the opening and closing of the jaws during use, which makes it very inconvenient to use and may even slow down the surgical process to a certain extent. Utility Model Content

[0004] Based on this, it is necessary to provide a forceps drive assembly and an electrosurgical instrument to address the problems of complex structure of electrosurgical closed cutting instruments and inconvenient opening and closing of the forceps.

[0005] In a first aspect, the present application provides a clamp head drive assembly, which adopts the following technical solution:

[0006] A clamp head drive assembly is driven and connected to a movable clamp head to adjust the relative position between the movable clamp head and the static clamp head, the clamp head drive assembly includes a moving part, a connecting part, a driving part and an elastic part, the moving part can move relative to the housing in a first direction, the moving part includes an open position, a closed position and a clamping position sequentially arranged relative to the housing, the moving part is provided with a sliding groove, the sliding groove extends along the first direction; the connecting part is slidably installed in the sliding groove and includes an initial position and an end position sequentially arranged relative to the housing, the connecting part also includes a mounting portion for mounting the movable clamp head; the driving part is connected to the housing The movable member drives the movable member to move along the first direction; the elastic member is installed in the sliding groove and sleeved on the periphery of the connecting member, and the elastic member abuts between the connecting member and the groove wall of the sliding groove; wherein, when the movable member is in the open position, the connecting member is in the initial position, and the dynamic pliers head is opened; when the movable member switches to the closed position, the connecting member switches to the final position, and the dynamic pliers head is affixed to the static pliers head; when the movable member switches to the clamping position, the connecting member is still in the final position, and the elastic member is compressed and applies pressure to the dynamic pliers head, so that the dynamic pliers head is pressed against the static pliers head.

[0007] In one embodiment, the connecting member includes a pull rod, a fixed sleeve and a ridge. Along the first direction, the pull rod is slidably installed in the sliding groove. The ridge and the mounting portion are arranged at opposite ends of the pull rod. The fixed sleeve is arranged on the pull rod and connected to the movable member. The elastic member is arranged on the outer periphery of the pull rod and abuts between the ridge and the fixed sleeve.

[0008] In one embodiment, the mounting portion is provided with a clearance notch and a snap-in groove, the clearance notch passes through the end surface of the mounting portion facing away from the pull rod, the snap-in groove is provided in the clearance notch and connected to the clearance notch, and the snap-in groove can rotatably mount the pliers head on the mounting portion.

[0009] In one embodiment, the pliers drive assembly further includes a guide pin, and along the first direction, the guide pin passes through the pull rod and the movable member.

[0010] In one embodiment, the pliers driving assembly further comprises a positioning ring and a connecting hoop provided in the sliding groove, the positioning ring is sleeved on the periphery of the pull rod and is fixed to the moving part by means of the connecting hoop.

[0011] In one embodiment, the driving member includes a wrench, a connecting part and a connecting rod, the wrench includes a swing end and a fixed end arranged at intervals, the fixed end is used to be rotatably mounted on the shell, the swing end can swing around the fixed end, the connecting part is connected to the moving member, and the connecting rod is rotatably connected between the swing end and the connecting part.

[0012] In one embodiment, the pliers drive assembly further includes a reset member, which is capable of abutting between the movable member and the housing and applying a thrust to the movable member so that the movable member maintains a tendency to move toward the open position.

[0013] In one embodiment, the stiffness coefficient of the reset member is smaller than the stiffness coefficient of the elastic member.

[0014] In one embodiment, the pliers head driving assembly further includes a rotating member, and the rotating member is used to connect the pliers head to drive the pliers head to rotate axially.

[0015] In a second aspect, the present application provides an electrosurgical instrument, which adopts the following technical solution:

[0016] An electrosurgical instrument includes a handle, a clamp head assembly and the above-mentioned clamp head drive assembly, wherein the handle includes a shell, the clamp head assembly includes a clamp rod and a clamp head, and the clamp rod connects the clamp head to the shell; the clamp head drive assembly is installed in the shell and is transmission-connected to the clamp rod to drive the clamp head to rotate axially or switch between open and closed states.

[0017] The aforementioned pliers drive assembly controls the opening and closing of the movable pliers by moving the movable member in a first direction. This allows the operator to quickly switch the pliers between open and closed states by driving the movable member through the drive member during use, thereby improving the convenience of opening and closing control. Furthermore, because the elastic member is sleeved around the periphery of the connecting member, compression of the elastic member allows continued pressure to be applied to the movable pliers even after the pliers are closed, thereby improving the stability of the clamping operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is an overall diagram of an electrosurgical instrument in one embodiment of the present application.

[0019] Figure 2 Schematic diagram of the structure of the clamp head assembly and the clamp head drive assembly in one embodiment of the present application.

[0020] Figure 3 This is an exploded view of the clamp head drive assembly in one embodiment of the present application.

[0021] Description of the accompanying drawings:

[0022] 1. Clamp head drive assembly; 11. Moving part; 111. Sliding groove; 12. Connecting part; 121. Mounting part; 1211. Notch; 1212. Clamping groove; 122. Pull rod; 123. Fixed sleeve; 124. Raised ridge; 13. Driving part; 131. Wrench; 1311. Fixed end; 1312. Swinging end; 132. Connecting part; 133. Connecting rod; 14. Elastic part; 15. Guide pin; 16. Positioning ring; 17. Connecting hoop; 18. Resetting part; 19. Rotating part; 191. Fixed seat; 192. Knob; 2. Handle; 21. Left half shell; 22. Right half shell; 3. Clamp head assembly; 31. Clamp rod; 32. Clamp head; 321. Stationary clamp head; 322. Moving clamp head; F1. First direction. DETAILED DESCRIPTION

[0023] To make the above-mentioned objects, features, and advantages of the present application more clearly understood, the specific embodiments of the present application are described in detail below with reference to the accompanying drawings. The following description sets forth many specific details to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways than those described herein, and those skilled in the art can make similar improvements without violating the scope of the present application. Therefore, the present application is not limited to the specific embodiments disclosed below.

[0024] In the description of this application, it should be understood that if the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. appear, the orientation or position relationship indicated by these terms is based on the orientation or position relationship shown in the accompanying drawings, which is only for the convenience of describing this application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this application.

[0025] In addition, if the terms "first" or "second" appear, these terms are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of technical features indicated. Therefore, a feature specified as "first" or "second" may explicitly or implicitly include at least one of such features. In the description of this application, if the term "plurality" appears, "plurality" means at least two, for example, two, three, etc., unless otherwise specifically defined.

[0026] In this application, unless otherwise specified or limited, the terms "mounted," "connected," "connected," "fixed," etc., should be interpreted broadly. For example, these terms may refer to fixed connections, removable connections, or integration; mechanical connections or electrical connections; direct connections or indirect connections through an intermediary; and internal communication between two components or interaction between two components, unless otherwise specified. Those skilled in the art will understand the specific meanings of these terms in this application based on the specific circumstances.

[0027] In this application, unless otherwise expressly specified or limited, if a first feature is described as being "above" or "below" a second feature, or similar descriptions, this may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Furthermore, when a first feature is described as being "above," "above," or "above" a second feature, it may mean that the first feature is directly above or diagonally above the second feature, or simply means that the first feature is at a higher level than the second feature. When a first feature is described as being "below," "below," or "below" a second feature, it may mean that the first feature is directly below or diagonally below the second feature, or simply means that the first feature is at a lower level than the second feature.

[0028] It should be noted that if an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be an intermediate element. If an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be an intermediate element. If any, the terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used in this application are for illustrative purposes only and do not represent the only implementation method. The "first direction" may be the extension direction of the clamp rod.

[0029] See Figure 1 and Figure 2 As shown, an embodiment of the present application provides an electrosurgical instrument, specifically an instrument that can enter the human body through a tiny wound and cut and coagulate blood vessels. The electrosurgical instrument includes a forceps head assembly 3, a forceps head drive assembly 1, and a handle 2. The forceps head drive assembly 1 is installed in the housing of the handle 2 and is transmission-connected to the forceps head assembly 3 to realize opening and closing control of the forceps head assembly 3.

[0030] Specifically, the forceps head assembly 3 includes a forceps head 32 and a forceps rod 31. The forceps head 32 is arranged at one end of the forceps rod 31 and is used to clamp tissue to facilitate coagulation or cutting treatment of the clamped tissue. The handle 2 is arranged at one end of the forceps rod 31 away from the forceps head 32 and is used for the operator to hold.

[0031] In the embodiment of the present application, the pliers 32 include a movable pliers 322 and a stationary pliers 321. The pliers rod 31 includes an inner rod movably connected to the movable pliers 322, with the movable pliers 322 rotatably mounted to the end of the inner rod away from the handle 2. The pliers rod 31 also includes an outer rod sleeved around the inner rod, with the stationary pliers 321 fixed to the end of the outer rod away from the handle 2. The pliers drive assembly 1 is mounted within the housing and controls the movable pliers 322 to swing relative to the stationary pliers 321 by movement of the inner rod in a first direction F1, thereby controlling the opening and closing of the pliers 32.

[0032] Continue reading Figure 2 As shown, in some embodiments, the pliers head driving assembly 1 includes a moving part 11, a connecting part 12, a driving part 13 and an elastic part 14. The connecting part 12 is slidingly connected to the moving part 11 by means of the elastic part 14. The driving part 13 is used to drive the moving part 11, the connecting part 12 and the elastic part 14 to move along the first direction F1 to drive the axial movement of the pliers rod 31.

[0033] Wherein, the movable member 11 is constructed as a slider with a sliding groove 111 on the top. Along the first direction F1, the movable member 11 includes an open position, a closed position and a clamping position that are sequentially arranged relative to the handle 2. The connecting member 12 includes a mounting portion 121 for the inner rod to be installed. The connecting member 12 can be slidably installed in the sliding groove 111 to drive the inner rod to slide along the first direction F1, thereby realizing the opening and closing control of the pliers 32. Along the first direction F1, the connecting member 12 includes an initial position and an end position that are sequentially arranged relative to the handle 2. The elastic member 14 is also installed in the sliding groove 111. The connecting member 12 includes a fixed sleeve 123 that is installed on the movable member 11. The elastic member 14 is sleeved on the periphery of the connecting member 12 and abuts between the connecting member 12 and the fixed sleeve 123 to realize the restriction of the relative position between the connecting member 12 and the movable member 11, and enables the connecting member 12 to move synchronously with the movement of the movable member 11 before the pliers 32 closes.

[0034] Specifically, when the driving member 13 does not apply a driving force to the moving member 11, the moving member 11 is in the open position, the connecting member 12 is in the initial position, and the clamp head 32 is open;

[0035] When the driving member 13 applies a certain driving force to the moving member 11, the moving member 11 moves from the open position to the closed position under the action of the driving force, and the connecting member 12 moves synchronously under the drive of the moving member 11 and reaches the final position, driving the movable clamp head 322 to rotate relative to the static clamp head 321, so as to realize the closing of the clamp head 32;

[0036] When the driving member 13 continues to apply driving force to the movable member 11, the movable member 11 continues to move from the closed position and reaches the clamping position under the driving force. At this time, since the clamp head 32 is already in a closed state, the inner rod connected to the movable clamp head 322 cannot continue to move, so that the connecting member 12 is limited to the final position. At this time, the movable member 11 continues to move and compresses the elastic member 14, and the elastic member 14 will apply a pressure to the connecting member 12 to drive the connecting member 12 to have a tendency to move synchronously with the movable member 11, thereby making the movable clamp head 322 have a tendency to continue to rotate toward the static clamp head 321, clamped to the static clamp head 321, to facilitate coagulation and cutting treatment of tissue.

[0037] See Figure 2 As shown, in some embodiments, the pliers head drive assembly 1 also includes a reset member 18 installed between the moving member 11 and the shell. The reset member 18 can abut between the moving member 11 and the shell, and apply a thrust to the moving member 11 in the opposite direction of the above-mentioned driving force, so that the moving member 11 always maintains a tendency to move toward the open position, thereby realizing the self-resetting function of the moving member 11.

[0038] In the embodiment of the present application, the reset member 18 and the elastic member 14 may be springs. It is understood that, in order to provide the operator with a better operating feel, the reset member 18 may be a spring with a smaller spring coefficient than that of the elastic member 14, so that the operator can more easily drive the moving member 11 to move with the help of the driving member 13.

[0039] In addition, during actual operation, since the spring coefficient of the reset member 18 itself is relatively small, it is not easy to cause excessive obstruction to the movement of the movable member 11, and the elastic member 14 has a larger spring coefficient. After the pliers head 32 is closed, the thrust generated by the compression of the elastic member 14 will also act on the movable member 11 and hinder the movement of the movable member 11, thereby allowing the operator to judge the state of the pliers head 32 by the resistance encountered when holding the handle 2, thereby improving the convenience of use of the electrosurgical instrument.

[0040] Combine Figure 2 and Figure 3 As shown, in some embodiments, the connecting member 12 further includes a pull rod 122 and a ridge 124. Along the first direction F1, the pull rod 122 is slidably mounted in the sliding groove 111. The aforementioned mounting portion 121 and ridge 124 are respectively provided at opposite ends of the pull rod 122. The ridge 124 is provided around the side wall of the pull rod 122. The mounting portion 121, the pull rod 122, and the ridge 124 are configured as an integrated structure. The aforementioned fixed sleeve 123 can specifically be a spring limiting sleeve. The fixed sleeve 123 is sleeved on one end of the pull rod 122 near the mounting portion 121 and connected to the movable member 11. The fixed sleeve 123 is slidably connected to the pull rod 122. The elastic member 14 is sleeved on the outer periphery of the pull rod 122 and abuts between the fixed sleeve 123 and the ridge 124 to achieve axial limitation of the elastic member 14.

[0041] In other embodiments, to facilitate assembly, a limit block is provided on the movable member 11, and a limit groove is defined circumferentially on the sidewall of the fixed sleeve 123. The limit block can be inserted into the limit groove along the second direction to facilitate quick assembly. After assembly, the limit block can abut against the wall of the limit groove along the first direction F1 to axially limit the fixed sleeve 123.

[0042] Furthermore, in some embodiments, the pliers drive assembly 1 also includes a guide pin 15, which is arranged between the pull rod 122 and the movable part 11 along the first direction F1, so that the pull rod 122 can always maintain a coaxial state with the movable part 11, thereby realizing the guiding and limiting function of the pull rod 122, so that the pull rod 122 always slides along the first direction F1.

[0043] In other embodiments, the pliers drive assembly 1 further includes a positioning ring 16 and a connecting hoop 17 disposed within the sliding groove 111. The positioning ring 16 can be mounted to the groove wall of the sliding groove 111 via the connecting hoop 17, and the connecting hoop 17 is connected to an external power source via a wire. In the embodiment of the present application, the pull rod 122 can be inserted through the positioning ring 16 along the first direction F1. During the movement of the pull rod 122, the inner ring of the positioning ring 16 can contact the side wall of the pull rod 122 to achieve guiding, conductive, and position-limiting functions for the pull rod 122.

[0044] In addition, due to the arrangement of the positioning ring 16 and the connecting hoop 17 , a certain gap is formed between the pull rod 122 and the groove wall of the sliding groove 111 for the installation of the elastic member 14 , thereby ensuring that the pull rod 122 can always slide smoothly along the first direction F1 .

[0045] Continue reading Figure 2 and Figure 3 As shown, in some embodiments, the driving member 13 includes a wrench 131, a connecting portion 132, and a connecting rod 133. Specifically, the wrench 131 includes a fixed end 1311 and a swing end 1312 spaced apart. The fixed end 1311 can be rotatably mounted on the handle 2 via a pin, and the swing end 1312 can swing around the fixed end 1311 under the driving force applied by the operator's hand. The connecting portion 132 is fixed to the moving member 11, and the connecting rod 133 is rotatably mounted between the swing end 1312 of the wrench 131 and the connecting portion 132.

[0046] During use, the operator applies an external force to the wrench 131 to drive the swing end 1312 of the wrench 131 to rotate about the fixed end 1311, and drives the connecting portion 132 to move along the first direction F1 through the connecting rod 133, thereby driving the movable member 11 to move along the first direction F1, and further driving the pull rod 122 to move, so as to close the clamp head 32. After the clamp head 32 is closed, the operator continues to apply external force to the wrench 131, and the movable member 11 will continue to move along the first direction F1 (from the closed position to the clamping position) and compress the elastic member 14, further causing the pull rod 122 to have a tendency to move along the first direction F1, thereby applying additional pressure to the movable clamp head 322, ensuring clamping stability, so as to facilitate tissue coagulation and cutting treatment.

[0047] Combine Figure 1 and Figure 3As shown, in some embodiments, the pliers head drive assembly 1 further includes a rotating member 19 mounted on the pliers rod 31, and the rotating member 19 includes a fixing seat 191 fixed to the pliers rod 31 and a knob 192 mounted on the fixing seat 191. In the embodiment of the present application, the fixing seat 191 is snap-fitted to the side wall of the pliers rod 31, and the housing includes a left half shell 21 and a right half shell 22 that can be snap-fitted to each other. The left half shell 21 and the right half shell 22 are jointly clamped to the fixing seat 191 to achieve axial limitation of the fixing seat 191.

[0048] The knob 192 is covered on the periphery of the left and right half shells 21 and 22 and the fixing base 191 and is engaged with the fixing base 191 . When the operator rotates the knob 192 , the fixing base 191 rotates, and further rotates the pliers rod 31 to complete the rotation of the pliers head 32 .

[0049] Furthermore, in order to meet the requirement of axial rotation of the pliers rod 31, the mounting portion 121 is constructed as a round rod-shaped structure coaxially arranged with the pull rod 122, and a clearance notch 1211 and a snap-in groove 1212 for connecting the inner rod are provided at one end of the mounting portion 121 away from the pull rod 122. In the embodiment of the present application, the clearance notch 1211 is a "U"-shaped notch that passes through the end face of the mounting portion 121 away from the pull rod 122, and the snap-in groove 1212 is provided in the clearance notch 1211 and communicates with the clearance notch 1211. The end of the inner rod away from the movable pliers head 322 can be rotatably mounted on the mounting portion 121 with the aid of the snap-in groove 1212, thereby being able to perform axial rotation while meeting the axial limit.

[0050] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0051] The above-described embodiments merely represent several implementation methods of the present application. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that a person of ordinary skill in the art may make various modifications and improvements without departing from the spirit of the present application, and these modifications and improvements fall within the scope of protection of the present application. Therefore, the scope of protection of the present patent application shall be determined by the appended claims.

Claims

1. A clamp head drive assembly, which is driven and connected to a movable clamp head to adjust the relative position between the movable clamp head and the static clamp head, characterized in that: The clamp head drive assembly includes: a moving member capable of moving relative to the housing along a first direction, the moving member including an open position, a closed position, and a clamping position sequentially arranged relative to the housing, the moving member defining a sliding groove extending along the first direction; a connecting member, slidably mounted in the sliding groove and including an initial position and an end position sequentially arranged relative to the housing, the connecting member further comprising a mounting portion for mounting a movable pliers head; a driving member connected to the moving member to drive the moving member to move along the first direction; and an elastic member installed in the sliding groove and sleeved on the periphery of the connecting member, wherein the elastic member abuts between the connecting member and the groove wall of the sliding groove; When the movable part is in the open position, the connecting part is in the initial position, and the movable pliers head is opened; when the movable part is switched to the closed position, the connecting part is switched to the final position, and the movable pliers head is attached to the static pliers head; when the movable part is switched to the clamping position, the connecting part is still in the final position, and the elastic part is compressed and applies pressure to the movable pliers head, so that the movable pliers head is pressed against the static pliers head.

2. The clamp head drive assembly according to claim 1, characterized in that: The connecting member includes a pull rod, a fixed sleeve and a ridge. Along the first direction, the pull rod is slidably installed in the sliding groove. The ridge and the mounting portion are arranged at opposite ends of the pull rod. The fixed sleeve is arranged on the pull rod and connected to the movable member. The elastic member is arranged on the outer periphery of the pull rod and abuts between the ridge and the fixed sleeve.

3. The clamp head drive assembly according to claim 2, characterized in that: The mounting portion is provided with a clearance notch and a snap-in groove. The clearance notch passes through the end surface of the mounting portion away from the pull rod. The snap-in groove is arranged in and connected to the clearance notch. The snap-in groove can rotatably mount the pliers head on the mounting portion.

4. The clamp head drive assembly according to claim 2, characterized in that: The pliers driving assembly further includes a guide pin, which passes through the pull rod and the moving part along the first direction.

5. The clamp head driving assembly according to claim 2, characterized in that: The clamp head driving assembly further comprises a positioning ring and a connecting hoop arranged in the sliding groove. The positioning ring is sleeved on the periphery of the pull rod and is fixed to the moving part by means of the connecting hoop.

6. The clamp head driving assembly according to claim 1, characterized in that: The driving member includes a wrench, a connecting part and a connecting rod. The wrench includes a swing end and a fixed end arranged at intervals. The fixed end is used to be rotatably mounted on the shell, and the swing end can swing around the fixed end. The connecting part is connected to the moving member, and the connecting rod is rotatably connected between the swing end and the connecting part.

7. The clamp head drive assembly according to claim 1, characterized in that: The pliers head driving assembly further comprises a reset member, which is capable of abutting between the moving member and the housing and applying a thrust to the moving member so as to keep the moving member in a trend of moving toward the open position.

8. The clamp head drive assembly according to claim 7, characterized in that: The stiffness coefficient of the reset member is smaller than the stiffness coefficient of the elastic member.

9. The clamp head driving assembly according to claim 1, characterized in that: The pliers head driving assembly further comprises a rotating member, which is used to connect the pliers head to drive the pliers head to rotate axially.

10. An electrosurgical instrument, characterized in that: include: a handle, including a housing; A pliers head assembly, comprising a pliers rod and a pliers head, wherein the pliers rod connects the pliers head to the housing; and The pliers head drive assembly according to any one of claims 1 to 9 is installed in the housing and is transmission-connected to the pliers rod to drive the pliers head to rotate axially or switch between open and closed states.

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