Medical stapler and end effector thereof

Abstract

The utility model relates to a kind of medical suturing device and its end effector, and the end effector includes nail bin, stop nail seat and push nail assembly, nail bin has multiple rows of nail groove groups, each row of nail groove group has multiple nail grooves arranged along the axial direction, and the nail groove is loaded with suture nail, the middle region of the nail surface of nail bin and / or the stop nail surface of stop nail seat is equipped with multiple convex parts sequentially arranged along the axial direction, and the convex part includes recessed area and the convex region separately arranged on the both sides of recessed area, and multiple rows of nail groove groups are distributed on the both sides of the convex part. By setting convex part in the middle region of the nail surface of nail bin and / or the stop nail surface of stop nail seat, the clamping force on the tissue can be effectively increased, and the tissue sliding or moving is avoided;Meanwhile, by setting recessed area in the middle region of convex part, when clamping tissue, the convex region on the both sides of recessed area can press out two rows of clear marks on the surface of tissue, and these marks provide accurate guidance for subsequent cutting operation, facilitating subsequent cutting operation.

Description

Technical Field

[0001] This utility model relates to the field of medical device technology, specifically to a medical suture device and its end effector. Background Technology

[0002] In modern surgery, suture devices are important medical instruments widely used in tissue suturing. A suture device typically consists of a handheld operating part and a working end. The handheld operating part is convenient for the surgeon to hold and manipulate, while the working end is used to directly contact the tissue and perform the suturing task. The working end is equipped with a pair of clamping members for clamping blood vessels or other tissues. The space between the clamping members is designed according to the specific tissue thickness and surgical requirements.

[0003] However, in actual surgery, the thickness and shape of tissue can vary due to individual differences, surgical site, and pathological condition. If the space between the clamping components does not match the tissue, especially if the space between the clamping mechanisms is too large, the tissue may slide or shift during clamping, causing the suture position to deviate from the intended target. Furthermore, existing suture devices cannot clearly mark the specific location to be cut after clamping blood vessels, which inconveniences the surgeon when using surgical scissors for subsequent cutting operations, increasing surgical time and difficulty. Utility Model Content

[0004] One objective of this invention is to provide an end effector that can prevent tissue from sliding or shifting during the clamping process, while marking the location to be cut to facilitate subsequent cutting operations.

[0005] Another objective of this invention is to provide a medical suture device comprising the aforementioned end effector.

[0006] To achieve the above objectives, the technical solution adopted by this utility model is as follows:

[0007] This utility model provides an end effector for a medical suture device, including a staple cartridge, an anvil seat movably disposed on the staple cartridge and capable of cooperating with the staple cartridge to clamp tissue, and a staple pusher assembly movably disposed within the staple cartridge and capable of moving axially in response to the handle of the medical suture device. The staple cartridge has multiple rows of staple slots, each row of staple slots having multiple staple slots arranged axially. The staple slots are loaded with suture staples. The middle area of ​​the staple ejection surface of the staple cartridge and / or the anvil surface of the anvil seat has multiple protrusions arranged sequentially axially. Each protrusion includes a recessed area and raised areas on both sides of the recessed area. The multiple rows of staple slots are distributed on both sides of the protrusions.

[0008] Unless otherwise specified, the surface of the staple cartridge opposite the anvil is the staple ejection surface, and the surface of the anvil opposite the staple cartridge is the staple abutment surface.

[0009] This invention effectively increases the clamping force on tissue and prevents tissue slippage or movement by providing a protrusion in the middle area of ​​the staple ejection surface of the staple cartridge and / or the staple abutment surface of the staple seat. At the same time, by providing a recessed area in the middle area of ​​the protrusion, when the instrument clamps the tissue, the protrusions on both sides of the recessed area can press two rows of clear imprints on the tissue surface, making it convenient for medical staff to cut the tissue between the two rows of imprints along the direction of the imprints, thus avoiding medical accidents caused by improper cutting.

[0010] In some embodiments, both the staple cartridge ejector surface and the staple anchor surface have protrusions in their middle regions, which are arranged in a one-to-one correspondence. When the end effector is in the closed state, the protrusions on the staple cartridge ejector surface and the corresponding protrusions on the staple anchor surface intersect each other, and their recessed areas overlap. The intersecting protrusions provide better clamping force.

[0011] Furthermore, when the end effector is in the closed state, the distance from the protruding area of ​​the protrusion on the nail-abutting surface to the nail-out surface, or the distance from the protruding area of ​​the protrusion on the nail-out surface to the nail-abutting surface, is less than the distance between the recessed area of ​​the protrusion on the nail-out surface and the recessed area of ​​the protrusion on the corresponding nail-abutting surface.

[0012] In some embodiments, the protrusion is inclined.

[0013] In some embodiments, the raised region has a high center and low sides.

[0014] Furthermore, the raised area transitions smoothly, and the connection between it and the recessed area also transitions smoothly to reduce tissue damage.

[0015] In some embodiments, the width of the middle area of ​​the nail-out surface and the nail-abutting surface is equal and is 1mm to 2mm, such as 1mm, 1.5mm, 2mm, etc.

[0016] In some embodiments, one or more sets of nail grooves are provided on each side of the protrusion.

[0017] This utility model also provides a medical suture device, including an elongated body, a handle, and an end effector as described above, wherein the handle and the end effector are respectively connected to both ends of the elongated body.

[0018] In some embodiments, the elongated body includes an outer tube and a push rod and an opening / closing assembly movably disposed within the outer tube and slidable along the axial direction. The distal ends of the push rod and the opening / closing assembly are respectively connected to the push rod assembly and the pin seat, and the proximal ends are connected to the handle. The push rod and the opening / closing assembly are capable of generating a push rod action and a closing action respectively in response to the handle.

[0019] In some embodiments, the handle includes a handle body and an operating part, a drive mechanism, and a closing and locking mechanism disposed on the handle body. The operating part is rotatably connected to the handle body, and the two ends of the operating part's rotation axis are respectively the operating end and the drive end. The drive mechanism includes a connector with one end rotatably and slidably connected to the drive end, a push block rotatably connected to the other end of the connector and slidable axially, an opening and closing drive member connected to the proximal end of the elongated body (specifically, an opening and closing assembly), and a firing drive member connected to the proximal end of the elongated body (specifically, a push rod). The opening and closing drive member and the firing drive member... The member is responsive to the operating part and can slide axially; the closing locking mechanism includes a closing locking member rotatably connected to the handle body, and an elastic member connected between the handle body and the closing locking member and giving the closing locking member a downward rotation tendency. The closing locking member has a first state and a second state. When the closing locking member is in the first state, the closing locking member causes the opening and closing drive member to abut between the closing locking member and the push block. When the closing locking member is in the second state, the closing locking member abuts against the opening and closing drive member and causes the opening and closing drive member not to interfere with the movement of the push block.

[0020] In some embodiments, the push block includes a push block body and a boss located at the upper end of the push block body. When the closing locking member is in the first state, the opening and closing driving member abuts against the boss.

[0021] In some embodiments, the opening and closing drive member has a first stepped surface, a second stepped surface located below the first stepped surface, and an abutting surface connected between the first stepped surface and the second stepped surface. When the closing locking member is in a first state, the closing locking member abuts against the first stepped surface; when the closing locking member is in a second state, the closing locking member abuts against the abutting surface.

[0022] In some embodiments, the closing locking mechanism further includes an operating knob connected to the closing locking member and at least partially exposed in the handle body.

[0023] Due to the application of the above technical solution, this utility model has the following advantages compared with the prior art:

[0024] This invention effectively increases the clamping force on the tissue by setting a protrusion in the middle area of ​​the staple cartridge ejection surface and / or the staple seat abutment surface, thus preventing tissue slippage or movement. At the same time, by setting a recessed area in the middle area of ​​the protrusion, when the instrument clamps the tissue, the protrusions on both sides of the recessed area can press two rows of clear imprints on the tissue surface. These imprints provide precise guidance for subsequent cutting operations, facilitating subsequent cutting operations. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the structure of a medical suture device provided in Example 1;

[0026] Figure 2 A schematic diagram of an end effector provided in Embodiment 1 (pig cartridge seat not shown);

[0027] Figure 3 for Figure 2 A cross-sectional view of plane AA;

[0028] Figure 4 for Figure 2 An enlarged schematic diagram of part I in the diagram;

[0029] Figure 5 A schematic diagram of the staple cartridge provided in Example 1 (the staple cartridge seat is not shown);

[0030] Figure 6 A schematic diagram of the anvil provided in Example 1;

[0031] Figure 7 A top view of the anvil provided in Embodiment 1;

[0032] Figure 8 This is a schematic diagram of the structure of a medical suture device from another angle, as provided in Embodiment 1.

[0033] Figure 9 for Figure 8 A cross-sectional view on the BB side;

[0034] Figure 10 for Figure 9 An enlarged schematic diagram of part II in the diagram;

[0035] Figure 11 The schematic diagram of the handle provided in Embodiment 1 (not showing the entire handle) shows that the closing locking member is in the first state;

[0036] Figure 12 The schematic diagram of the handle provided in Embodiment 1 (not showing the entire handle) shows that the closing locking member is in the second state;

[0037] Among them, 1. End actuator; 11. Staple cartridge seat; 12. Staple cartridge body; 121. Staple outlet surface; 122. Staple groove; 13. Staple abutment seat; 131. Staple abutment surface; 132. Waist-shaped groove; 14. Protrusion; 141. Recessed area; 142. Protruding area;

[0038] 2. Slender body; 21. Outer tube; 22. Push rod; 23. Opening / closing rod; 24. Opening / closing rod return elastic element;

[0039] 3. Handle; 31. Handle body; 32. Operating part; 321. Operating end; 322. Driving end; 33. Connecting part; 34. Push block; 341. Boss; 35. Opening / closing driving part; 351. First step surface; 352. Abutting surface; 353. Second step surface; 36. Firing driving part; 37. Closing locking part; 371. Operating knob; 38. Closing locking part reset elastic element; 39. Operating part reset elastic element;

[0040] D. Width of the middle area. Detailed Implementation

[0041] The present invention will be further described below with reference to the embodiments shown in the accompanying drawings.

[0042] Example 1:

[0043] A medical suture device, such as Figures 1 to 12 As shown, it includes an end effector 1, an elongated body 2, and a handle 3.

[0044] The end effector 1 includes a staple cartridge, an anvil 13 rotatably mounted on the staple cartridge and capable of engaging with the staple cartridge to clamp tissue, and a staple pusher assembly slidably disposed within the staple cartridge and capable of axial movement in response to the handle 3 of the medical suture device. The middle region of the staple ejection surface 121 of the staple cartridge and / or the anvil surface 131 of the anvil 13 is provided with a plurality of axially arranged protrusions 14, each protrusion 14 including a recessed region 141 and protruding regions 142 respectively disposed on both sides of the recessed region 141. In this embodiment, as... Figures 2 to 7As shown, both the staple ejection surface 121 of the staple cartridge and the staple abutment surface 131 of the staple holder 13 have protrusions 14 in their middle areas. These protrusions 14 correspond one-to-one. When the end effector 1 is in the closed state, the protrusions 14 of the staple ejection surface 121 and their corresponding protrusions 14 of the staple abutment surface 131 intersect each other, and their recessed areas 141 overlap. The intersecting protrusions 14 provide better clamping force, effectively preventing tissue slippage. Simultaneously, when the instrument clamps the tissue, the protrusions 142 on both sides of the recessed area 141 can press two rows of clear imprints onto the tissue surface, providing precise guidance for subsequent cutting operations. This facilitates subsequent cutting by medical personnel along the imprints and between the two rows of imprints, avoiding medical accidents caused by incorrect cutting positions during manual cutting.

[0045] Preferably, when the end effector 1 is in the closed state, the distance from the protruding area 142 of the protrusion 14 on the anvil surface 131 to the nail dispensing surface 121, or the distance from the protruding area 142 of the protrusion 14 on the nail dispensing surface 121 to the anvil surface 131, is less than the distance between the recessed area 141 of the protrusion 14 on the anvil surface 131 and the nail dispensing surface 121. The specific size can be designed according to the actual tissue thickness and is not specifically limited. Furthermore, the protrusion 14 is inclined, with a higher middle height and lower side heights for its protruding area 142, and a smooth transition at the connection between the protruding area 142 and the recessed area 141 to reduce tissue damage. The width D of the middle area of ​​the nail dispensing surface 121 of the staple cartridge and the anvil surface 131 of the anvil seat 13 is equal and 1mm to 2mm, which facilitates subsequent manual cutting and meets the requirements of instrument miniaturization.

[0046] The staple cartridge includes a staple cartridge seat 11 and a staple cartridge body 12 detachably mounted on the staple cartridge seat 11. The staple cartridge seat 11 is based on existing technology and will not be described in detail here. The staple outlet surface 121 is located on the staple cartridge body 12, which also has multiple rows of staple grooves distributed on both sides of the protrusion 14, meaning that one or more sets of staple grooves are provided on each side of the protrusion 14. Each row of staple grooves has multiple axially arranged staple grooves 122, which contain suture staples. The suture staple structure and installation method are based on existing technology, and its material is preferably a biocompatible titanium alloy. In this embodiment, one row of staple grooves is provided on each side of the protrusion 14. In other embodiments, to further improve the suturing effect, at least two sets of staple grooves are provided on each side of the protrusion 14, with the staple grooves 122 on adjacent sets of staple grooves on the same side being staggered.

[0047] The staple pusher assembly includes a staple pusher slider and a slider drive that are axially slidably disposed within the staple cartridge body 12. The slider drive is located at the proximal end of the staple pusher slider and can slide distally under the action of the staple pusher rod 22 of the elongated body 2, thereby pushing the staple pusher slider distally to push the staple out of the staple slot 122 and anchor it to the tissue under the action of the abutment surface 131. The structure of the staple pusher slider and slider drive is not specifically limited in this application and can be referred to in the prior art.

[0048] The elongated body 2 includes an outer tube 21, a push rod 22 movably disposed within the outer tube 21 and slidable axially, and an opening / closing assembly. The distal end of the push rod 22 is connected to the push rod assembly, specifically to the slider pusher, and the proximal end is connected to the handle 3. The push rod 22 can generate a push action in response to the handle 3. The opening / closing assembly includes an opening / closing rod 23 and an opening / closing rod return elastic element 24. The distal end of the opening / closing rod 23 is rotatably and slidably connected to the waist-shaped groove 132 of the anvil seat 13 via a fixed shaft thereon, and the proximal end is connected to the handle 3. The opening / closing rod 23 can generate a closing action in response to the handle 3. That is, when the opening / closing rod 23 slides toward the distal end, it can push the anvil seat 13 to rotate, thereby achieving closure. The opening / closing rod return elastic element 24 is disposed between the proximal end of the opening / closing rod 23 and the handle 3, which gives the opening / closing rod 23 a tendency to slide toward the proximal end to keep the end actuator 1 in the open state.

[0049] The handle 3 includes a handle body 31 and an operating part 32, a drive mechanism and a closing locking mechanism provided on the handle body 31.

[0050] The operating part 32 is rotatably connected to the handle body 31, with the operating end 321 and the driving end 322 located at the two ends of its rotation axis, respectively. An operating part reset elastic element 39 is provided between the operating part 32 and the handle body 31, which causes the driving end 322 of the operating part 32 to tend to move towards the proximal end.

[0051] The drive mechanism includes a connector 33, a pusher block 34, an opening / closing drive 35, and a firing drive 36. One end of the connector 33 is rotatably and slidably connected to the drive end 322, and the other end is rotatably connected to the pusher block 34. The pusher block 34 is slidably disposed axially, having a pusher block body and a boss 341 disposed above the pusher block body. The pusher block 34 can slide axially under the drive of the connector 33. The opening / closing drive 35 is connected to the proximal end of the opening / closing lever 23 and can slide axially toward the distal end under the drive of the pusher block 34. Further, the opening / closing drive 35 has a first stepped surface 351, a second stepped surface 353 located below the first stepped surface 351, and an abutment surface 352 connecting the first stepped surface 351 and the second stepped surface 353. The firing drive 36 is connected to the proximal end of the pusher rod 22 and can slide axially toward the distal end under the push of the pusher block 34.

[0052] The closing locking mechanism includes a closing locking member 37 rotatably connected to the handle body 31, and an elastic member (i.e., a closing locking member reset elastic member 38) connected between the handle body 31 and the closing locking member 37 and giving the closing locking member 37 a downward rotation tendency. The closing locking member 37 has a first state and a second state. When the closing locking member 37 is in the first state, the closing locking member 37 presses down on the first step surface 351, causing the proximal end of the opening and closing drive member 35 to deform downward and abut against the closing locking member 37 and the push block 34. At this time, the operating part 32 on the operating handle 3 (i.e., pressing the operating part 32 towards the proximal end) and the connecting member 33 can move the push block 34 towards the distal end. The boss 341 on the push block 34 abuts against the opening and closing drive member 35. The opening and closing drive member 35 can move towards the distal end under the push of the push block 34, so that the opening and closing rod 23 overcomes the force of the opening and closing rod reset elastic member 24 on it and moves towards the distal end, thereby causing the pin seat 13 to rotate towards the direction of the pin cartridge, and the end actuator 1 switches to the closed state. When the end effector 1 switches to the closed state, the first step surface 351 just passes over the closing locking member 37. Under the action of the elastic member on it, the closing locking member 37 abuts against the abutment surface 352, keeping the end effector 1 in the closed state. At this time, the closing locking member 37 is in the second state. When the closing locking member 37 is in the second state, since the closing locking member 37 removes the downward abutment force on the first step surface 351, the proximal end of the opening and closing drive member 35 recovers its deformation and does not contact the push member, thus not interfering with the movement of the push block 34. When the operating part 32 is operated again, the push block 34 can continue to move towards the distal end, thereby pushing the firing lever towards the distal end to drive the push pin assembly towards the distal end and push out the stitching pin, completing the firing action.

[0053] Furthermore, the closing locking mechanism also includes an operating knob 371 connected to the closing locking member 37 and at least partially exposed on the handle body 31. By rotating the operating knob 371, the contact between the closing locking member 37 and the abutment surface 352 of the opening / closing drive member 35 can be released, and the opening / closing drive member 35 will reset under the action of the spring force thereon.

[0054] In the foregoing, only certain exemplary embodiments have been briefly described. As those skilled in the art will recognize, the described embodiments can be modified in various ways without departing from the spirit or scope of the present invention. Therefore, the drawings and description are considered exemplary in nature and not restrictive.

[0055] In the description of the embodiments of this utility model, it should be understood that "distal end" refers to the end of the instrument or component away from the operator, and "proximal end" refers to the end of the instrument or component closer to the operator; "axial direction" refers to the direction parallel to the line connecting the centers of the distal and proximal ends of the instrument or component; "inner" and "outer" are positions defined by distance relative to the center of the instrument or component, where "inner" is the position closer to the center of the instrument or component, and "outer" is the position away from the center of the instrument or component; "upper" and "lower" refer to the orientation of the instrument in its actual use or working state. The above description of directional terms is only for the convenience of describing the embodiments of the present invention and simplifying the description, and is not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the embodiments of this utility model.

[0056] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of embodiments of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified.

[0057] In this embodiment of the invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0058] The foregoing disclosure provides many different implementations or examples for carrying out different structures of the embodiments of this utility model. To simplify the disclosure of the embodiments of this utility model, specific examples of components and arrangements are described above. Of course, these are merely examples and are not intended to limit the embodiments of this utility model. Furthermore, reference numerals and / or reference letters may be repeated in different examples of the embodiments of this utility model; such repetition is for simplification and clarity and does not in itself indicate a relationship between the various implementations and / or arrangements discussed.

[0059] The above embodiments are only for illustrating the technical concept and features of this utility model, and are intended to enable those skilled in the art to understand the content of this utility model and implement it accordingly. They should not be construed as limiting the scope of protection of this utility model. All equivalent changes or modifications made in accordance with the spirit and essence of this utility model should be included within the scope of protection of this utility model.

Claims

1. An end effector for a medical suture device, comprising a staple cartridge, an anvil (13) movably disposed on the staple cartridge and capable of cooperating with the staple cartridge to clamp tissue, and a staple pusher assembly movably disposed within the staple cartridge and capable of axial movement in response to a handle (3) of the medical suture device, wherein the staple cartridge has multiple rows of staple slots, each row of staple slots having multiple axially arranged staple slots (122), and staples are loaded in the staple slots (122), characterized in that: The middle area of ​​the nail ejection surface (121) of the nail cartridge and / or the nail abutment surface (131) of the nail abutment (13) is provided with a plurality of protrusions (14) arranged sequentially along the axial direction. The protrusions (14) include a recessed area (141) and protruding areas (142) respectively disposed on both sides of the recessed area (141). The multi-row nail groove group is distributed on both sides of the protrusions (14).

2. The end effector of the medical suture device according to claim 1, characterized in that: The middle area of ​​the nail-out surface (121) and the nail-stopping surface (131) are provided with protrusions (14) and are provided in a one-to-one correspondence. When the end actuator (1) is in the closed state, the protrusions (14) of the nail-out surface (121) and the protrusions (14) of the corresponding nail-stopping surface (131) intersect each other and the recessed areas (141) of the two have overlapping areas.

3. The end effector of the medical suture device according to claim 2, characterized in that: When the end actuator (1) is in the closed state, the distance from the protruding area (142) of the protrusion (14) on the nailing surface (131) to the nail exiting surface (121) or the distance from the protruding area (142) of the protrusion (14) on the nail exiting surface (121) to the nailing surface (131) is less than the distance between the recessed area (141) of the protrusion (14) on the nail exiting surface (121) and the recessed area (141) of the protrusion (14) on the corresponding nailing surface (131).

4. The end effector of the medical suture device according to claim 1, characterized in that: The protrusion (14) is inclined.

5. The end effector of the medical suture device according to claim 1, characterized in that: The raised area (142) has a high middle height and low sides.

6. The end effector of the medical suture device according to claim 5, characterized in that: The raised area (142) transitions smoothly, and the portion where it connects with the recessed area (141) also transitions smoothly.

7. The end effector of the medical suture device according to claim 1, characterized in that: The width of the middle area of ​​the nail-out surface (121) and the nail-abutting surface (131) is equal and is 1mm to 2mm.

8. A medical suture device comprising an elongated body (2), a handle (3), and an end effector (1), the handle (3) and the end effector (1) being respectively connected to both ends of the elongated body (2), the handle (3) being configured to generate a closing action to open or close the end effector (1) and to generate a firing action to suture tissue, characterized in that: The end effector (1) is the end effector (1) according to any one of claims 1 to 7.

9. The medical suture device according to claim 8, characterized in that: The handle (3) includes a handle body (31) and an operation part (32), a drive mechanism and a closing locking mechanism disposed on the handle body (31). The operation part (32) is rotatably connected to the handle body (31). The two ends of the operation part (32) located on its rotation axis are the operation end (321) and the drive end (322) respectively. The drive mechanism includes a connector (33) with one end rotatably and slidably connected to the drive end (322), a push block (34) rotatably connected to the other end of the connector (33) and slidable along the axial direction, and an opening / closing drive (35) and a firing drive (36) respectively connected to the proximal end of the elongated body (2). The opening / closing drive (35) and the firing drive (36) are slidable along the axial direction in response to the operation part (32). The closing locking mechanism includes a closing locking member (37) rotatably connected to the handle body (31) and an elastic member connected between the handle body (31) and the closing locking member (37) and giving the closing locking member (37) a downward rotation tendency. The closing locking member (37) has a first state and a second state. When the closing locking member (37) is in the first state, the closing locking member (37) causes the opening and closing drive member (35) to abut between the closing locking member (37) and the push block (34). When the closing locking member (37) is in the second state, the closing locking member (37) abuts against the opening and closing drive member (35) and causes the opening and closing drive member (35) not to interfere with the movement of the push block (34).

10. The medical suture device according to claim 9, characterized in that: The push block (34) includes a push block body and a boss (341) located at the upper end of the push block body. When the closing locking member (37) is in the first state, the opening and closing driving member (35) abuts against the boss (341); and / or, The opening and closing drive member (35) has a first stepped surface (351), a second stepped surface (353) located below the first stepped surface (351), and an abutting surface (352) connecting the first stepped surface (351) and the second stepped surface (353). When the closing locking member (37) is in the first state, the closing locking member (37) abuts against the first stepped surface (351); when the closing locking member (37) is in the second state, the closing locking member (37) abuts against the abutting surface (352).

Images