Knob assembly and circular tube type stapler

Abstract

The present invention provides a knob assembly and a circular tube-type stapler, wherein the knob assembly includes a selectively linked knob driver and a knob body, the knob body is sleeved on the outside of the screw rod, and the knob body drives the screw rod to move along the axial direction of the stapler when it rotates; one of a first mating piece and a second mating piece is respectively arranged on the knob driver and the knob body, the first mating piece is an elastic mating piece, and the first mating piece has a blocking state and a yielding state, when the first mating piece is in the blocking state, the first mating piece is linked with the second mating piece, and when the first mating piece is in the yielding state, the first mating piece and the second mating piece are not linked. By adopting the present invention, when the knob driver is rotated, when the resistance of the knob body reaches the preset resistance value, the knob assembly will no longer be able to transmit a greater torque, and the knob assembly at this time enters a failure mode, and the gap between the nail anvil assembly and the nail magazine remains unchanged, and the tissue will not be over-compressed.

Description

Technical Field

[0001] The present invention relates to the technical field of medical devices, and in particular to a knob assembly and a circular tubular stapler. Background Art

[0002] Digestive tract diseases are one of the most common diseases in humans. During the treatment process, circular tubular staplers are often used to replace the doctor's manual operation to anastomose physiological tissues such as the digestive tract. Circular tubular staplers are a common surgical instrument, most of which use axial internal stapling to form end-to-end or end-to-side anastomosis of physiological tissues such as the esophagus, stomach, and intestines during surgery. During the anastomosis, the two sections of tissue are contained inwardly in the stapler. After the firing is completed, a circular anastomosis is formed on the tissue, reconstructing the human body channel.

[0003] In the prior art, a circular tube-type stapler includes a stapler body, an operating handle movably connected to the stapler body, and a nail anvil assembly matched with the body. The stapler body includes a nail magazine assembly arranged at the distal end, the nail magazine assembly includes an annular nail magazine, a cutter; and a knob arranged at the proximal end of the body, the knob can rotate relative to the body, and the interior of the stapler body also includes a nail anvil shaft arranged from the proximal end to the distal end. Here, the distal end and the proximal end are relative to the operator, the end closer to the operator is the proximal end, and the end farther from the operator, that is, the end closer to the surgical site is the distal end. In the stapler, the inner side and the outer side are relative to the axis of the stapler, the side close to the axis is the inner side, and the side away from the axis is the outer side. The nail anvil assembly includes a nail anvil, a nail anvil cap arranged at the distal end of the nail anvil, and a knife anvil arranged inside the nail anvil. The nail anvil assembly can be directly connected to the distal end of the nail anvil shaft or connected through a nail anvil shaft connector. During tumor surgery, after the tumor tissue is cut off and removed, the anvil shaft passes through the purse of the residual tissue and is arranged at the distal end of the stapler body. The knob is rotated to gradually reduce the distance between the anvil assembly and the stapler to a suitable distance, and then the firing state is reached. Only then can the operating handle be held to fire the instrument to complete the anastomosis. With the continuous development of medical devices, circular tube staplers are also increasingly widely used in the treatment of diseases such as hemorrhoids.

[0004] In the process of rotating the knob to move the anvil assembly closer to the nail magazine, sometimes the knob can still be rotated after the tissue is closed. In this way, the anvil assembly and the nail magazine will continue to get closer, continue to compress the tissue, cause excessive squeezing of the tissue, and may even crush the tissue, which is very unfavorable to the surgical outcome. Summary of the invention

[0005] In response to the problems in the prior art, the purpose of the present invention is to provide a knob assembly and a circular tubular stapler. When the knob driving part is rotated, when the resistance of the knob body reaches a preset resistance value, the knob assembly will no longer be able to transmit a larger torque. At this time, the knob assembly enters a failure mode, and the gap between the anvil assembly and the staple magazine remains unchanged without causing the tissue to be over-compressed.

[0006] An embodiment of the present invention provides a knob assembly for a circular tubular stapler, wherein a wire rod is disposed inside the stapler; the knob assembly comprises:

[0007] A knob driving member and a knob body, wherein the knob body is sleeved on the outside of the screw rod, and when the knob body rotates, the screw rod is driven to move along the axial direction of the stapler;

[0008] A first matching piece and a second matching piece, wherein the first matching piece is an elastic matching piece and has a blocking state and a yielding state. When the first matching piece is in the blocking state, the first matching piece and the second matching piece are linked to each other, and when the first matching piece is in the yielding state, the first matching piece and the second matching piece are not linked to each other;

[0009] The first matching piece is arranged on the knob driving piece, and the second matching piece is arranged on the knob body; or the first matching piece is arranged on the knob body, and the second matching piece is arranged on the knob driving piece.

[0010] Optionally, when the knob driving member is rotated by an external force and the rotational resistance of the knob body is greater than a preset resistance value, the first matching member is deformed by the force of the second matching member and enters a yielding state.

[0011] Optionally, the first matching piece is a spring sheet having a protrusion.

[0012] Optionally, a spring installation groove is provided on the knob driving member or the knob body, and two ends of the spring are installed in the spring installation groove.

[0013] Optionally, the elastic sheet includes a first guiding surface, and when the knob driving component rotates toward a first direction, the first guiding surface of the first matching component contacts the second matching component.

[0014] Optionally, the first guiding surface is a curved surface or an inclined surface.

[0015] Optionally, the elastic sheet includes a second guiding surface, and when the knob driving component rotates toward the second direction, the second guiding surface of the first matching component contacts the second matching component.

[0016] Optionally, the second guiding surface is a curved surface or an inclined surface.

[0017] Optionally, the second mating piece includes at least one mating structure, and the mating structure is a protrusion or a groove.

[0018] Optionally, the matching structure includes a first side surface, and when the knob driving component rotates toward a first direction, the first side surface of the matching structure contacts the first matching component, and the first side surface is inclined toward the first direction.

[0019] Optionally, the matching structure includes a second side surface, and when the knob driving component rotates toward the second direction, the second side surface of the matching structure contacts the first matching component.

[0020] Optionally, the second side surface of the matching structure is a right-angled surface, or the second side surface of the matching structure is inclined toward the second direction, and the inclination degree of the second side surface of the matching structure is smaller than the inclination degree of the first side surface of the matching structure.

[0021] Optionally, the knob driving member comprises a knob housing, and the first matching member or the second matching member is provided on the inner side surface of the knob driving member.

[0022] Optionally, a first boss is disposed on the outer side of the knob body, the first mating piece is disposed on the inner side of the knob housing, and the second mating piece is disposed on the proximal side or the distal side of the boss; or

[0023] The second matching piece is arranged on the inner side surface of the knob housing, and the first matching piece is arranged on the proximal side or the distal side of the boss.

[0024] Optionally, a second boss is further provided on the outer side of the knob body, and the second boss is located on the proximal side of the first boss;

[0025] The first matching piece or the second matching piece is disposed on the second boss, and the height of the first matching piece or the second matching piece disposed on the second boss is lower than the height of the first boss, and the distal end of the knob body matches with the first boss.

[0026] Optionally, it further includes a knob back cover located at the proximal end of the knob body, the distal end of the knob back cover is provided with a back cover internal thread, and the proximal end of the knob body is provided with a body external thread that matches the back cover internal thread.

[0027] The embodiment of the present invention further provides a circular tubular stapler, comprising the knob assembly.

[0028] The knob assembly and the circular tube-type stapler provided by the present invention have the following advantages:

[0029] The present invention provides a knob assembly for a circular tube-type stapler, wherein the knob assembly is divided into a knob body and a knob driving member, wherein the knob driving member is selectively linked with the knob body, and before the rotational resistance experienced by the knob body reaches a preset resistance value, the knob driving member can drive the knob body to rotate together, and the knob body can drive the nail anvil assembly to move along the axial direction of the stapler and approach the nail magazine through a screw rod, and after the rotational resistance experienced by the knob body reaches the preset resistance value, the knob driving member cannot drive the knob body to rotate due to deformation of the elastic matching member, and at this time the knob assembly enters a failure mode, and the gap between the nail anvil assembly and the nail magazine remains unchanged, without causing excessive compression of the tissue. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Other features, objectives and advantages of the present invention will become more apparent from a reading of the detailed description of non-limiting embodiments made with reference to the following accompanying drawings.

[0031] Figure 1 is a schematic structural diagram of a stapler according to a first embodiment of the present invention;

[0032] Figure 2 is a schematic diagram of the cooperation between the knob assembly and the screw rod according to the first embodiment of the present invention;

[0033] Figure 3 yes Figure 2 A1-A1 cross-sectional view;

[0034] Figure 4 is a schematic structural diagram of a second boss according to a first embodiment of the present invention;

[0035] Figure 5 is a schematic structural diagram of a knob body according to a first embodiment of the present invention;

[0036] Figure 6 is a schematic structural diagram of a spring piece according to a first embodiment of the present invention;

[0037] Figure 7 is a schematic structural diagram of a knob housing according to a first embodiment of the present invention;

[0038] Figure 8 is a schematic structural diagram of a first knob back cover of a first embodiment of the present invention;

[0039] Fig. 9 is a schematic diagram of the cooperation between the knob assembly and the screw rod according to the second embodiment of the present invention;

[0040] Fig.10 yes Fig. 9 A cross-sectional view along the A2-A2 direction;

[0041] Fig.11 is a schematic structural diagram of a knob body according to a second embodiment of the present invention;

[0042] Fig.12 is a schematic structural diagram of a spring piece according to a second embodiment of the present invention;

[0043] Fig.13 2 is a schematic structural diagram of a knob housing according to a second embodiment of the present invention.

[0044] Reference numerals:

[0045] First embodiment

[0046] 1 Knob body 213 Second end of the spring

[0047] 11 protrusion 214 first guide surface of the spring

[0048] 111 first side surface of the protrusion 215 second guide surface of the spring

[0049] 112 raised second side surface 22 spring piece installation groove

[0050] 12 External thread of the body 5 First knob back cover

[0051] 13 Body internal thread 51 Back cover internal thread

[0052] 14 First boss 6 screw rod

[0053] 15 Second boss 7 Second knob back cover

[0054] 2 Knob housing 81 Stapler body housing

[0055] 21 shrapnel 82 nail magazine assembly

[0056] 211 raised portion of the spring 83 nail anvil assembly

[0057] 212 first end of the shrapnel 84 handle

[0058] Second embodiment

[0059] 3 Knob body 32 Spring clip installation slot

[0060] 31 spring piece 33 first boss

[0061] 311 raised portion of the spring 34 second boss

[0062] 312 First end of the spring 4 Knob housing

[0063] 313 The second end 41 of the spring is protruding

[0064] 314 first guide surface of the spring piece 411 first side surface of the protrusion

[0065] 315 second guide surface of the spring piece 412 second side surface of the protrusion DETAILED DESCRIPTION

[0066] Example embodiments will now be described in more detail with reference to the accompanying drawings. However, example embodiments can be implemented in a variety of forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that the present invention will be comprehensive and complete and fully convey the concepts of the example embodiments to those skilled in the art. The same reference numerals in the figures represent the same or similar structures, and thus their repeated description will be omitted.

[0067] In order to solve the technical problems in the prior art, the present invention provides a knob assembly for a circular tubular stapler, wherein a screw is disposed inside the stapler, and the knob assembly includes a selectively linked knob driver and a knob body, wherein the knob body is sleeved on the outside of the screw, and when the knob body rotates, the screw is driven to move along the axial direction of the stapler. One of two mating parts is respectively disposed on the knob driver and the knob body, and the two mating parts include a first mating part and a second mating part. That is, the first mating part and the second mating part are respectively disposed on the knob driver and the knob body, or the first mating part and the second mating part are respectively disposed on the knob body and the knob driver. The present invention further provides a circular tubular stapler, including the knob assembly.

[0068] Wherein, the first fitting part is an elastic fitting part, and the first fitting part has a blocking state and a yielding state. When the first fitting part is in the blocking state, the first fitting part and the second fitting part are linked together. When the first fitting part is in the yielding state, the first fitting part and the second fitting part are not linked together.

[0069] When the operator rotates the knob driver in a first direction, the knob driver transmits a rotational torque through two mating parts. Before the rotational resistance experienced by the knob body reaches a preset resistance value, the first mating part is in a blocking state, i.e., blocking the relative movement between the knob driver and the knob body. The knob driver can drive the knob body to rotate together through the two mating parts, i.e., the two mating parts are in a linkage state. The knob body further drives the anvil assembly to move along the axial direction of the stapler and approach the staple magazine assembly through the screw rod.

[0070] As the nail anvil assembly gradually approaches the nail magazine assembly, when the distance between the nail anvil assembly and the nail magazine assembly reaches a suitable value, and the squeezing force on the tissue reaches a suitable predetermined value, the knob is rotated again, and the knob body is subjected to resistance that hinders the rotation in the first direction. This resistance corresponds to the squeezing force on the tissue between the nail anvil assembly and the nail magazine assembly. At this time, the knob body can only be rotated in the first direction by applying a rotation torque greater than the resistance on the knob body. That is, when the rotation resistance of the knob body reaches the preset resistance value, the interaction force between the first matching member and the second matching member is greater than the force of the elastic matching member to overcome the elastic deformation, and the first matching member is deformed and enters a yielding state, that is, it no longer blocks the relative movement between the knob driver and the knob body, and the knob driver and the knob body are no longer linked. At this time, the knob assembly enters a failure mode, and the gap between the nail anvil assembly and the nail magazine remains unchanged, and the tissue is not over-squeezed.

[0071] The following is a detailed description of the circular tubular stapler and the knob assembly provided by two embodiments of the present invention in conjunction with the accompanying drawings. Figures 1 to 8 The structure of the knob assembly of the first embodiment of the present invention is shown, wherein the first matching member is arranged on the knob driving member, and the second matching member is arranged on the knob body; Figures 9 to 13 The structure of the knob assembly of the second embodiment of the present invention is shown, wherein the first matching member is arranged on the knob body, and the second matching member is arranged on the knob driving member.

[0072] like Figure 1 As shown, the structure of the stapler of the first embodiment is shown. The stapler includes a stapler body and a nail anvil assembly 83, wherein the stapler body includes a stapler housing 81, a nail magazine assembly 82 located at the distal end of the stapler housing 81, a knob assembly located at the proximal end of the stapler housing 81, and a screw rod 6 arranged from the proximal end to the distal end, the nail magazine assembly 82 includes an annular nail magazine and a cutter, and the nail anvil assembly 83 includes a nail anvil and a nail anvil shaft, and the nail anvil is connected to the distal end of the screw rod through the nail anvil shaft. When the knob assembly rotates, the nail anvil assembly 83 is driven to move axially through the screw rod and the nail anvil shaft in turn, away from or close to the nail magazine assembly 82.

[0073] Of course, in another type of circular tubular stapler, such as the circular tubular stapler for hemorrhoid surgery mentioned above, the anvil assembly 83 is directly connected to the stapler body, and the anvil assembly 83 cannot be removed from the stapler body. In this case, the anvil assembly 83 does not include an anvil shaft, and the anvil is directly connected to the distal end of the screw rod.

[0074] like Figures 2 to 8As shown, the knob assembly includes a knob body 1 and a knob driver. In this embodiment, the knob driver is a knob housing 2. When the operator operates the knob assembly, he directly contacts the knob housing 2, but the present invention is not limited to this. The knob body 1 is sleeved on the outside of the screw rod 6, and the knob body 1 cooperates with the screw rod 6 through the internal body internal thread 13. When the knob body 1 rotates in a first direction, it can drive the screw rod 6 to move toward the proximal end of the stapler, and further drive the anvil assembly 83 to approach the stapler assembly 82. When the knob body 1 rotates in a second direction, it can drive the screw rod 6 to move toward the distal end of the stapler, so that the anvil assembly 83 is away from the stapler assembly 82. In this embodiment, the first mating member is arranged on the knob housing 2, and the second mating member is arranged on the knob body 1. Among them, the first mating piece is an elastic mating piece, and the first mating piece has a blocking state and a yielding state. When the first mating piece is in the blocking state, the first mating piece and the second mating piece are linked together, and the knob shell 2 and the knob body 1 are linked together. When the first mating piece is in the yielding state, the first mating piece and the second mating piece are not linked together, and the knob shell 2 and the knob body 1 are not linked together.

[0075] In this embodiment, the first matching piece is a spring 21 having a protrusion 211. A spring installation groove 22 is provided on the inner side of the knob housing 2, and the first end 212 and the second end 213 of the spring 21 are installed in the spring installation groove 22. The spring 21 can be a metal spring or a plastic spring, or other structures that can be elastically deformed and can return to the initial state after the external force is removed. This is only one way to set the elastic matching piece. In other alternative embodiments, the elastic matching piece can also adopt a structure of a spring and a movable block, etc., which are all within the protection scope of the present invention.

[0076] The second matching member includes at least one matching structure, which is a protrusion or a groove. In this embodiment, the second matching member includes a plurality of protrusions 11, and the plurality of protrusions 11 are evenly distributed on the outer surface of the knob body 1. The protrusion 11 has a first side surface 111 and a second side surface 112. When the knob housing 2 rotates toward the first direction, the first side surface 111 of the protrusion 11 contacts the spring 21, and when the knob housing 2 rotates toward the second direction, the second side surface 112 of the protrusion 11 contacts the spring 21.

[0077] When the operator operates the knob assembly, he first applies an external force to make the knob housing 2 rotate due to the external force. The knob housing 2 and the knob body 1 transmit the external force to the knob body 1 through two mating parts. The first mating part will give a rotational force to the second mating part. If the rotational resistance of the knob body 1 is less than the preset resistance value at this time, the reaction force of the second mating part on the first mating part is less than the force of the spring piece 21 to overcome the elastic deformation, the spring piece 21 will not be deformed, and the first mating part is in a blocking state. The knob housing 2 drives the knob body 1 to rotate together through the cooperation of the spring piece 21 and the protrusion 11. When the operator applies external force to drive the knob housing 2 to rotate, if the rotation resistance of the knob body 1 reaches or exceeds the preset resistance value, the operator needs to apply a greater external force. At this time, the reaction force of the protrusion 11 on the spring 21 is greater than the force of the spring 2 to overcome the elastic deformation. The spring 21 is deformed by the force of the protrusion 11 and enters a yielding state, that is, the protrusion 11 and the spring 21 cannot transmit external force to the knob body 1, the knob housing 2 cannot be linked with the knob body 1, and the knob housing 2 performs invalid idling and can emit a clicking sound when the protrusion 11 and the spring 21 are disengaged. At this time, the knob assembly is in a failed state, the nail forming gap between the nail anvil assembly 83 and the nail magazine assembly 82 remains unchanged, and the tissue will not be over-squeezed. If the operator hears a clicking sound or can judge that the current nail anvil assembly 83 has moved into place based on the feel of rotating the knob assembly in the failed state, the firing operation of the stapler can be performed.

[0078] In this embodiment, the spring sheet 21 includes a first guide surface 214. When the knob housing 2 rotates toward the first direction, the first guide surface 214 of the spring sheet 21 contacts the protrusion 11. The first guide surface 214 may be a curved surface or an inclined surface. The spring sheet 21 may also include a second guide surface 215. When the knob housing 2 rotates toward the second direction, the second guide surface 215 of the spring sheet 21 contacts the protrusion 11. The second guide surface 215 may be a curved surface or an inclined surface.

[0079] like Figure 2 As shown, the outer side of the knob body 1 is provided with a first boss 14, the proximal side of the first boss 14 is further provided with a second boss 15, and the protrusion 11 is provided on the second boss 15. Figure 3 and Figure 4 As shown in the figure, the second boss 15 and the plurality of protrusions 11 form a gear disc structure. This is only one embodiment, and in other alternative embodiments, only one boss may be provided, or the second boss 15 may be provided at the distal end of the first boss 14, etc., all of which are within the scope of protection of the present invention.

[0080] In this embodiment, the height of the protrusion 11 on the second boss 15 is lower than the height of the first boss 14; adaptively, a step surface is provided at the distal end of the rotating shell 2 to cooperate with the first boss 14 to limit the axial movement of the knob housing; a spring sheet 2 is provided on the inner side of the distal end of the rotating shell 2 to cooperate with the protrusion 11.

[0081] Furthermore, a knob back cover is also provided at the proximal end of the knob assembly, and the knob back cover includes a first knob back cover 5 and a second knob back cover 7. The distal end of the first knob back cover 5 is provided with a back cover internal thread 51, and the proximal end of the knob body 1 is provided with a body external thread 12 that matches the back cover internal thread. The first knob back cover 5 is threadedly connected to the proximal end of the knob body 1, and the second knob back cover 7 can be installed on the proximal end of the first knob back cover 5.

[0082] exist Figure 3 and Figure 4 In the perspective of , the first direction is clockwise and the second direction is counterclockwise. Figure 3 and Figure 4 As shown, in this embodiment, the first side surface 111 of the protrusion 11 is inclined toward the first direction, so that when the knob housing 2 rotates in the clockwise direction and is not linked with the knob body 1, the deformed spring sheet 2 is more likely to pass over the protrusion 11. The second side surface 112 of the protrusion 11 is an approximately right-angled surface or the second side surface 112 is inclined toward the second direction to hinder the knob housing from rotating in the second direction, so as to provide tactile feedback to the doctor and prompt the doctor to rotate in the direction. Here, the second side surface 112 of the protrusion 11 is an approximately right-angled surface, which means that the second side surface 112 is substantially perpendicular to the outer side surface of the knob body 1. If the second side surface 112 of the protrusion 11 is inclined toward the second direction, the inclination of the second side surface 112 is less than the inclination of the first side surface 111. In this way, when the knob housing 2 rotates in the second direction, the spring sheet 2 is not easy to pass over the protrusion 11, thereby preventing the knob assembly from being unable to drive the knob body 1 to rotate in the second direction to increase the distance between the nail magazine assembly 82 and the nail anvil assembly 83 when the reverse operation is required after the knob assembly is tightened in the first direction.

[0083] like Figures 9 to 13 , which shows the structure of the knob assembly of the second embodiment of the present invention. The difference between the second embodiment and the first embodiment is that the first matching piece is arranged on the knob body 3, and the second matching piece is arranged on the knob housing 4.

[0084] exist Fig.10In the perspective of , the first direction is counterclockwise, and the second direction is clockwise. The first matching member is a spring piece 31 including a protrusion 311, and the second matching member includes a plurality of protrusions 41 arranged on the inner side of the knob housing 4. When the knob body 3 rotates along the first direction, the spring piece 31 contacts the first side surface 411 of the protrusion 41, and when the knob body 3 rotates along the second direction, the spring piece 31 contacts the second side surface 412 of the protrusion 41. Similarly, the inclination of the first side surface 411 is greater than the inclination of the second side surface 412, so that when the rotating shell 4 rotates along the first direction, when the rotation resistance of the knob body 3 is greater than the preset resistance value, the spring piece 31 is more easily disengaged from the protrusion 41, and it is ensured that after the rotating shell 4 is tightened along the first direction, the knob body 3 can be driven to rotate through the knob shell 4 in the second direction.

[0085] The outer side surface of the knob body 3 is provided with an elastic sheet installation groove 32, and the two ends 312 and 313 of the elastic sheet 31 are respectively arranged in the elastic sheet installation groove 32. The elastic sheet 31 includes a first guide surface 314 and a second guide surface 315. When the knob body 3 rotates in the first direction, the first guide surface 314 of the elastic sheet 31 contacts the first side surface 411 of the protrusion 41, and when the knob body 3 rotates in the second direction, the second guide surface 315 of the elastic sheet 31 contacts the second side surface 412 of the protrusion 41.

[0086] In this embodiment, the knob body 1 is provided with a first boss 33 and a second boss 34, and the second boss 34 is provided on the proximal side of the first boss 33. The first boss 33 acts with the distal end of the knob housing 4 to limit the axial movement of the knob housing. The spring piece mounting groove 32 is provided on the outer surface of the second boss 34. The distal end of the knob housing 4 cooperates with the first boss 33.

[0087] The working principle of the knob assembly of the second embodiment is similar to that of the knob assembly of the first embodiment. When the operator operates the knob assembly, he first applies an external force to rotate the knob housing 4. The knob housing 4 transmits the external force to the knob body 3 through two matching parts. The first matching part will give a rotational force to the second matching part. If the rotational resistance of the knob body 3 is less than the preset resistance value at this time, the force of the second matching part on the first matching part is less than the force of the spring 31 to overcome the elastic deformation, the spring 31 will not be deformed, and the first matching part is in a blocking state. The knob housing 4 drives the knob body 3 to rotate together through the matching of the spring 31 and the protrusion 41. When the operator applies external force to drive the knob housing 4 to rotate, if the rotation resistance of the knob body 3 reaches or exceeds the preset resistance value, the operator needs to apply a greater external force. At this time, the force exerted by the protrusion 41 on the spring 31 is greater than the force of the spring 31 to overcome the elastic deformation. The spring 31 is deformed by the force of the protrusion 41 and enters a yielding state, that is, the protrusion 41 and the spring 31 cannot transmit external force to the knob body 3, the knob housing 4 cannot be linked with the knob body 3, the knob housing 4 performs invalid idling, and can emit a clicking sound when the protrusion 41 and the spring 31 are disengaged. At this time, the knob assembly is in a failed state, the nail forming gap between the nail anvil assembly 83 and the nail magazine assembly 82 remains unchanged, and the tissue will not be over-squeezed. If the operator hears a clicking sound or can judge that the current nail anvil assembly 83 has moved into place based on the feel of rotating the knob assembly in the failed state, the firing operation of the stapler can be performed.

[0088] It can be understood that, no matter in the first embodiment or in the second embodiment, the number of the spring pieces can be two or more. For example, when there are two spring pieces, they can be symmetrically arranged to enhance the stability of the structure.

[0089] The two embodiments provided in the present invention are only examples. In practical applications, some features of the two embodiments may be combined to obtain a new technical solution. Alternatively, one or some of the features may be changed to obtain a new technical solution, which all fall within the scope of protection of the present invention. For example, the first matching piece may not adopt a spring structure, but a structure in which a movable block and a spring cooperate, and the magnitude of the force to overcome the elastic deformation is the spring force of the spring. The second matching piece may not adopt a protrusion, but a groove structure, and the number and arrangement of the matching structures may also be selected as required.

[0090] The knob assembly and the circular tube-type stapler provided by the present invention have the following advantages:

[0091] The present invention provides a knob assembly for a circular tube-type stapler, wherein the knob assembly is divided into a knob body and a knob driving member, wherein the knob driving member is selectively linked with the knob body, and before the rotational resistance experienced by the knob body reaches a preset resistance value, the knob driving member can drive the knob body to rotate together, and the knob body can drive the nail anvil assembly to move along the axial direction of the stapler and approach the nail magazine through a screw rod, and after the rotational resistance experienced by the knob body reaches the preset resistance value, the knob driving member cannot drive the knob body to rotate due to deformation of the elastic matching member, and at this time the knob assembly enters a failure mode, and the gap between the nail anvil assembly and the nail magazine remains unchanged, without causing excessive compression of the tissue.

[0092] The above contents are further detailed descriptions of the present invention in combination with specific preferred embodiments, and it cannot be determined that the specific implementation of the present invention is limited to these descriptions. For ordinary technicians in the technical field to which the present invention belongs, several simple deductions or substitutions can be made without departing from the concept of the present invention, which should be regarded as falling within the protection scope of the present invention.

Claims

1. A knob assembly, characterized in that: Used for a circular tube-type stapler, a wire rod is arranged inside the stapler; the knob assembly comprises: A knob driving member and a knob body, wherein the knob body is sleeved on the outside of the screw rod, and when the knob body rotates, the screw rod is driven to move along the axial direction of the stapler; a first matching piece and a second matching piece, wherein the first matching piece is a spring piece with a protrusion, and the second matching piece includes at least one matching structure, and the matching structure is a protrusion or a groove; the first matching piece has a blocking state and a yielding state, and when the first matching piece is in the blocking state, the first matching piece and the second matching piece are linked, and when the first matching piece is in the yielding state, the first matching piece and the second matching piece are not linked; The first matching piece is arranged on the knob driving piece, and the second matching piece is arranged on the knob body; or the first matching piece is arranged on the knob body, and the second matching piece is arranged on the knob driving piece.

2. The knob assembly according to claim 1, characterized in that: When the knob driving member is rotated by an external force and the rotation resistance of the knob body is greater than a preset resistance value, the first matching member is deformed by the force of the second matching member and enters a yielding state.

3. The knob assembly according to claim 2, characterized in that: The knob driving member or the knob body is provided with a spring installation slot, and the two ends of the spring are installed in the spring installation slot.

4. The knob assembly according to claim 2, characterized in that: The elastic sheet includes a first guiding surface, and when the knob driving component rotates toward a first direction, the first guiding surface of the first matching component contacts the second matching component.

5. The knob assembly according to claim 4, characterized in that: The first guiding surface is a curved surface or an inclined surface.

6. The knob assembly according to claim 4, characterized in that: The elastic sheet includes a second guiding surface, and when the knob driving component rotates toward the second direction, the second guiding surface of the first matching component contacts the second matching component.

7. The knob assembly according to claim 6, characterized in that: The second guiding surface is a curved surface or an inclined surface.

8. The knob assembly according to claim 1, characterized in that: The matching structure includes a first side surface. When the knob driving component rotates toward a first direction, the first side surface of the matching structure contacts the first matching component, and the first side surface is inclined toward the first direction.

9. The knob assembly according to claim 8, characterized in that: The matching structure includes a second side surface, and when the knob driving component rotates toward the second direction, the second side surface of the matching structure contacts the first matching component.

10. The knob assembly according to claim 9, characterized in that: The second side surface of the matching structure is a right-angled surface, or the second side surface of the matching structure is inclined toward the second direction, and the inclination degree of the second side surface of the matching structure is smaller than the inclination degree of the first side surface of the matching structure.

11. The knob assembly according to claim 1, characterized in that: The knob driving member comprises a knob housing, and the first matching member or the second matching member is arranged on the inner side surface of the knob driving member.

12. The knob assembly according to claim 11, characterized in that: The outer side surface of the knob body is provided with a first boss, the first matching piece is provided on the inner side surface of the knob housing, and the second matching piece is provided on the proximal side or the distal side of the boss; or The second matching piece is arranged on the inner side surface of the knob housing, and the first matching piece is arranged on the proximal side or the distal side of the boss.

13. The knob assembly according to claim 12, characterized in that: The outer side surface of the knob body is also provided with a second boss, and the second boss is located at the proximal end side of the first boss; The first matching piece or the second matching piece is disposed on the second boss, and the height of the first matching piece or the second matching piece disposed on the second boss is lower than the height of the first boss, and the distal end of the knob body matches with the first boss.

14. The knob assembly according to claim 1, characterized in that: It also includes a knob back cover located at the proximal end of the knob body, the distal end of the knob back cover is provided with a back cover internal thread, and the proximal end of the knob body is provided with a body external thread that matches the back cover internal thread.

15. A circular tubular stapler, characterized in that: A knob assembly comprising any one of claims 1 to 14.

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