Secondary firing safety mechanism for cutting stapler

Abstract

The present invention relates to a secondary firing safety mechanism for a cutting stapler, wherein the cutting stapler (100) is provided with a cutting knife arranged in a hollow shell, and the cutting knife is configured to be able to move toward the proximal side and toward the distal side along the axial direction of the shell, and is characterized in that the secondary firing safety mechanism is provided with a secondary firing safety piece (130) arranged on the outer peripheral side of the shell and capable of moving in conjunction with the movement of the cutting knife, and a blocking pin (140) arranged in a through hole (128) in the shell wall, and the blocking pin is configured so that: during a primary firing process, the blocking pin is biased away from the cutting knife by a biasing member and does not protrude from the through hole to the inside of the shell, so as to allow the cutting knife to advance from the proximal side to the distal side and then withdraw from the distal side to the proximal side; when a secondary firing is desired, the secondary firing safety piece pushes the blocking pin against the biasing force of the biasing member, so that the blocking pin at least partially protrudes from the through hole to the inside of the shell, so as to prevent the cutting knife from advancing from the proximal side to the distal side.

Description

Technical Field

[0001] The present invention relates to a secondary firing safety mechanism for a cutting stapler, and in particular to a secondary firing safety mechanism for a disposable cutting stapler. Background Art

[0002] Cutting staplers are widely used in various minimally invasive surgeries, such as for the excision, transection and anastomosis of tissues in open surgery in abdominal surgery, gynecology, pediatrics and thoracic surgery. The cutting stapler is usually constructed to clamp the tissue to be excised or transected between two jaw members, and the cutting knife extending through the two jaw members excises or transects the tissue. In order to perform anastomosis on the tissue incision, one of the two jaw members usually includes a staple magazine in which the staples are stored, and the other usually includes an anvil that cooperates with it. Such a cutting stapler is usually disposable. After the cutting stapler is used (i.e., the cutting knife is fired) once, there are no more staples in the staple magazine. If the doctor mistakenly uses the cutting stapler for a second time at this time, there will be a risk that only the cutting knife cuts the tissue but fails to suture the tissue incision, which is easy to cause medical accidents such as surgical failure. For this reason, the cutting stapler needs to be provided with a safety mechanism to prevent the cutting knife from firing twice. For example, the prior art discloses a cutting stapler provided with the following secondary firing safety mechanism, which includes a sleeve member provided with a firing adjustment through hole, a firing safety block and a reed provided on an inner core in the sleeve member, etc. However, the industry still hopes to provide an improved secondary firing safety mechanism, or more alternative secondary firing safety solutions, so that manufacturers or users can select an appropriate secondary firing safety mechanism according to specific application scenarios, manufacturing processes, etc.

[0003] In addition, in practice, a firing test is required before the cutting stapler leaves the factory for sale or medical use. Due to the secondary firing safety that is provided, the cutting stapler cannot be used for a second firing after being fired once in the test. In this case, the secondary firing safety needs to be reset after the test. For example, the cutting stapler of the prior art resets the secondary firing safety mechanism by pressing the firing safety block through the firing adjustment through hole of the sleeve from the outside. However, there is a problem of uneven pressing force causing the firing safety block to be distorted. If the firing safety block is distorted after resetting, it cannot be ensured that the secondary firing safety mechanism will function correctly during subsequent medical use. Summary of the invention

[0004] In order to overcome at least one of the above-mentioned shortcomings existing in the prior art, according to a first aspect of the present invention, a secondary firing safety mechanism for a cutting stapler is provided, wherein the cutting stapler is provided with a cutting knife arranged in a hollow shell, and the cutting knife is configured to be able to move proximally and distally along the axial direction of the shell, and is characterized in that the secondary firing safety mechanism is provided with a secondary firing safety piece arranged on the outer peripheral side of the shell and capable of moving in conjunction with the movement of the cutting knife, and a blocking pin arranged in a through hole in the shell wall, and the blocking pin is configured so that: during a single firing process, the blocking pin is biased away from the cutting knife by a biasing member and does not protrude from the through hole to the inside of the shell, so as to allow the cutting knife to advance from the proximal side to the distal side and then withdraw from the distal side to the proximal side; when a secondary firing is desired, the secondary firing safety piece pushes the blocking pin against the biasing force of the biasing member, so that the blocking pin at least partially protrudes from the through hole to the inside of the shell, so as to prevent the cutting knife from advancing from the proximal side to the distal side. The secondary firing safety mechanism of the cutting stapler of the present invention can reliably prevent the cutting knife from firing a second time, thereby avoiding the situation where the cutting knife cuts the tissue but fails to suture the tissue incision; and the secondary firing safety mechanism has a simple structure and reset function.

[0005] According to a preferred embodiment, the secondary firing safety element comprises an elongated body extending in the axial direction of the housing, and the housing is provided with an axial groove longer than the elongated body in the peripheral side wall thereof. In this way, the elongated body can be accommodated on the peripheral side of the housing in a manner that it can slide along the axial groove between the distal end position and the proximal end position.

[0006] According to a preferred embodiment, the elongated body of the secondary firing safety piece is provided with a cantilever arm capable of moving perpendicularly to the axial direction under the action of an external force, the cantilever arm is provided with a first protrusion at the free end, the first protrusion is configured to protrude from the axial through slot provided at the bottom of the axial groove to the inside of the housing, and the cutting knife is provided with a corresponding second protrusion. Such a first protrusion and a second protrusion can be used to realize the linkage between the cutting knife and the secondary firing safety piece.

[0007] According to a preferred embodiment, the first protrusion of the secondary firing safety piece is in a triangular structure with an inclined surface located on the near side and a vertical surface located on the far side, and the second protrusion of the cutting knife is in a triangular structure with an inclined surface located on the far side and a vertical surface located on the near side. Such a first protrusion and a second protrusion are simple in structure and easy to manufacture.

[0008] According to a preferred embodiment, the first protrusion and the second protrusion are configured such that: when the cutting knife advances from the proximal side to the distal side during a firing process, the inclined surface of the second protrusion of the cutting knife presses the inclined surface of the first protrusion of the secondary firing safety member toward the axial through slot, so that the first protrusion retracts toward the axial through slot to allow the cutting knife to pass; and when the cutting knife after being fired once withdraws from the distal side to the proximal side, the vertical surface of the second protrusion of the cutting knife abuts against the vertical surface of the first protrusion of the secondary firing safety member, so that the secondary firing safety member moves toward the proximal side together with the cutting knife until the secondary firing safety member reaches its proximal end position. In this way, the "activation" of the secondary firing safety mechanism can be achieved through the linkage between the first protrusion of the secondary firing safety member and the second protrusion of the cutting knife. Here, "activation" means that the secondary firing safety mechanism can prevent the secondary firing of the cutting knife thereafter.

[0009] According to a preferred embodiment, the elongated body is provided with a stepped portion, which includes, in sequence from the proximal side to the distal side, a first step portion with the lowest height, an inclined portion obliquely rising from the first step portion toward the distal side and connected between the first step portion and the second step portion, and the second step portion with a height greater than the first step portion but lower than the rest of the elongated body. By integrally providing such a stepped portion on the secondary firing safety piece, it is possible to cooperate with the blocking pin in a simple manner to achieve the function of preventing the cutting knife from firing a second time.

[0010] According to a preferred embodiment, when the secondary firing safety piece is at the distal end position, the first step portion with the lowest height is located below the blocking pin, so that the biasing member biases the blocking pin away from the cutting knife, so that the blocking pin does not protrude from the through hole to the inside of the housing. At this time, the blocking pin that does not protrude from the through hole to the inside of the housing allows the cutting knife to be fired once.

[0011] According to a preferred embodiment, when the secondary firing safety piece is located at the proximal end position, a second step portion having a height greater than the first step portion but lower than the rest of the elongated body is located below the blocking pin, so as to push the blocking pin against the biasing force of the biasing member, so that the blocking pin at least partially protrudes from the through hole to the inside of the housing, thereby preventing the cutting knife from advancing from the proximal side to the distal side. At this time, the blocking pin protruding from the through hole to the inside of the housing prevents the cutting knife from passing through, thereby preventing the secondary firing of the cutting knife.

[0012] According to a preferred embodiment, the cutting knife is provided with a third protrusion, and when the secondary firing safety piece is located at the distal end position, the third protrusion can pass over the blocking pin so that the cutting knife can advance from the proximal side to the distal side and withdraw from the distal side to the proximal side; when the secondary firing safety piece is located at the proximal end position, the blocking pin prevents the third protrusion from passing through so as to prevent the cutting knife from advancing from the proximal side to the distal side.

[0013] According to a preferred embodiment, the secondary firing safety mechanism of the cutting stapler that has been fired once can be reset as follows: hook the cantilever arm of the secondary firing safety member with a hook through the adjustment opening on the outer sleeve of the cutting stapler, pull the cantilever arm outward to release the abutment between the first protrusion of the secondary firing safety member and the second protrusion of the cutting knife, and then pull the cantilever arm distally after the abutment is released to move the secondary firing safety member to its distal end position. The secondary firing safety mechanism of the cutting stapler of the present invention can be simply and reliably reset, and it is not easy to damage the relevant parts of the cutting stapler during the reset process.

[0014] According to a preferred embodiment, the biasing device is a compression spring in a compressed state, and the blocking pin is a metal pin clamped between the coils of the compression spring.

[0015] Further features of the present invention will become apparent from the following description of exemplary embodiments with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The present invention will now be described in detail below with reference to the accompanying drawings. It is to be understood that the drawings are not necessarily drawn to scale; in addition, for ease of illustration, components shown in a particular drawing may be omitted in other views. The drawings are only used to illustrate exemplary embodiments of the present invention and should not be considered to limit the scope of the present invention. In the drawings:

[0017] Figure 1 is a perspective view schematically showing an execution assembly of a cutting stapler 100 according to an exemplary embodiment of the present invention;

[0018] Figure 2 is an exploded perspective view schematically showing the components of the execution assembly of the cutting stapler 100;

[0019] Figure 3 yes Figure 2 an enlarged view of part A;

[0020] Figure 4 is a partial enlarged view schematically showing the secondary firing safety member 130 in its most distal end position P1;

[0021] Figure 5 is a partial enlarged view schematically showing the secondary firing safety member 130 in its most proximal end position P2;

[0022] Figure 6 is a cross-sectional view schematically showing an initial state of an actuator assembly of the cutting stapler 100 before first use;

[0023] Figure 7 yes Figure 6 an enlarged cross-sectional view of a portion B;

[0024] Figure 8 is a cross-sectional view schematically showing a state after the cutting knife 120 of the cutting stapler 100 is fired once;

[0025] Fig. 9 yes Figure 8 an enlarged cross-sectional view of a portion C;

[0026] Fig.10 is a cross-sectional view schematically showing a state where the cutting knife 120 is pulled back to just contact the secondary firing safety piece 130 after the cutting is completed;

[0027] Fig.11 yes Fig.10 an enlarged cross-sectional view of a portion D of FIG.

[0028] Fig.12 is a cross-sectional view schematically showing a state when the cutting knife 120 is pulled back to the proximal end position P2 and the blocking pin 140 is in a blocking position capable of blocking the cutting knife 120 from being fired again; and

[0029] Fig.13 yes Fig.12 An enlarged cross-sectional view of portion E of FIG. DETAILED DESCRIPTION

[0030] The exemplary embodiments of the present invention will be described in detail below with reference to the accompanying drawings. However, it should be understood that the description of the various embodiments is merely illustrative and does not serve as any limitation to the technology of the present invention. It should also be understood that the embodiments disclosed herein can be combined in various ways to provide more additional embodiments.

[0031] It should be understood that the same reference numerals represent the same elements in all the drawings. In the drawings, for the sake of clarity, the sizes of some components may be deformed, enlarged or reduced; or in order to highlight some components, some components may be omitted or represented in simplified drawings.

[0032] Unless otherwise specified, all terms used in the specification have the meanings commonly understood by those skilled in the art. For the sake of brevity and / or clarity, well-known functions or structures are not described in detail.

[0033] Unless otherwise specified, the singular forms "a", "the" and "the" used in the specification may include plural forms. The terms "include", "comprise" and "contain" used in the specification indicate the presence of the claimed features, but do not exclude the presence of one or more other features. The term "and / or" used in the specification includes any and all combinations of one or more of the relevant listed items.

[0034] In the specification, when an element is referred to as being “on,” “attached to,” “connected to,” or “contacting” another element, etc., the element may be directly on, directly attached to, directly connected to, or directly contacting the other element, or intervening elements may be present.

[0035] In the specification, the words "first", "second", "third", etc. are used only to distinguish the various components, and are not intended to limit the order and function of the various components. In addition, the "second" or "third" or other subsequent components can be set without setting or using the "first" or other prior components.

[0036] In the specification, “proximal side” refers to the side close to the operator of the cutting stapler 100 , and “distal side” refers to the side away from the operator (ie, close to the patient).

[0037] In the specification, unless otherwise specified, "left", "right", "upper", "lower", "outer", "inner", etc. are all in reference to directions in the drawings. It should be understood that spatial relationship terms such as "left", "right", "upper", "lower", "outer", "inner", etc. are intended to be used to describe the relationship between one feature and another feature in the drawings. It should be understood that the spatial relationship terms include not only the orientations shown in the drawings, but also different orientations of the cutting stapler 100 during use or operation.

[0038] First, refer to Figure 1-2A cutting stapler 100 according to an exemplary embodiment of the present invention, in particular, an actuator of the cutting stapler 100 configured to cut and staple tissue is described. The actuator of the cutting stapler 100 includes a pair of clamping members 110 configured to be closed relative to each other to clamp the tissue to be cut in the middle and to be opened relative to each other. Specifically, the pair of clamping members includes a staple magazine component 111 in which staples for stapling are stored, and a staple support 112 opposite to the staple magazine component 111. The actuator of the cutting stapler 100 also includes a cutting knife 120 configured to cut (e.g., resect or transect) tissue, and a drive sleeve 121 configured to drive the cutting knife 120 to move along its longitudinal axis, and the drive sleeve 121 can then be operatively connected to an actuation source such as an actuation handle (not shown) of the cutting stapler 100 via, for example, an actuation rod (not shown). The cutting knife 120 is a sheet-like member, and the plane in which it is arranged is orthogonal to the plane in which the clamping surface 113 of the staple cartridge component 111 and the plane in which the clamping surface 114 of the anvil 112 are located. The staple cartridge component 111 and the anvil 112 are respectively provided with a first slot 115 and a second slot 116 for accommodating the cutting knife 120 advancing toward the tissue to be cut. Usually, the cutting knife 120 and its driving sleeve 121 in a standby state are accommodated in a cylindrical housing composed of an upper half shell 122 and a lower half shell 123 that are opposite to each other. The upper half shell 122 and the lower half shell 123 are then accommodated in a sleeve 124. The staple cartridge component 111 and the anvil 112 are respectively operably connected to the upper half shell 122 and the lower half shell 123 via an adapter 117, a rotating head pin 118, a connecting piece 119, etc.

[0039] Next, the secondary firing safety mechanism of the cutting stapler 100 will be described in detail. Figure 3 As shown in the partial enlarged view of FIG. 1 , the secondary firing safety mechanism includes a secondary firing safety piece 130. The secondary firing safety piece 130 is configured to include an elongated body 131 extending along the axial direction of the lower half shell 123 (i.e., the forward and backward movement direction of the cutting knife 120) and two arc-shaped arms 132 extending laterally from the elongated body 131 to both sides. The two arc-shaped arms 132 together form a semicircular ring-shaped piece orthogonal to the elongated body 131. Figure 4 , 5 As shown, in the outer peripheral side wall of the lower half shell 123, an axial groove 125 formed by cutting off a part of the lower half shell 123 and a circumferential groove 126 orthogonal to the axial groove 125 are provided, which are used to accommodate the elongated body 131 and the arc-shaped arm 132 of the secondary firing safety member 130 respectively. Figure 4 , 5In the figure, for the convenience of illustration, the sleeve 124 located outside the lower half shell 123 is removed. However, in the assembled state, the secondary firing safety piece 130 will be clamped between the lower half shell 123 and the sleeve 124 with a certain clearance. The axial length of the axial groove 125 is greater than the axial length of the elongated body 131 of the secondary firing safety piece 130, so the elongated body 131 can move in the axial groove 125 along the axial direction of the lower half shell 123. Similarly, the width of the circumferential groove 126 in the axial direction is also greater than the width of the arcuate arm 132 in the axial direction, so the arcuate arm 132 can move in the circumferential groove 126 along the axial direction of the lower half shell 123. The circumferential groove 126 is used to limit the two stroke end positions of the secondary firing safety piece 130 relative to the lower half shell 123, namely the distal end position P1 (see Figure 4 ) and the proximal end position P2 (see Figure 5 The arc-shaped arm 132 may also be provided with a hook portion 133 at the free end thereof, which is configured to be hooked to a corresponding portion of the lower housing 123 , for movably attaching the secondary firing safety member 130 to the lower housing 123 .

[0040] The elongated body 131 of the secondary firing safety member 130 is provided with a cantilever arm 134 at the distal end. The cantilever arm 134 can move within a certain range along a direction perpendicular to the axial direction (i.e., the radial direction of the shell, or the up and down direction) under the action of an external force. The sleeve 124 is provided with an adjustment opening (not shown) for resetting the secondary firing safety mechanism at a position corresponding to the cantilever arm 134. The cantilever arm 134 is provided with a first protrusion 135 protruding upward from the inner surface of the elongated body 131 at the free end on the proximal side. In addition, at the bottom of the axial groove 125 of the lower half shell 123, a penetrating axial through groove 125' is provided (see Figure 4 , 5 ). The first protrusion 135 is configured to protrude into the housing through the axial through slot 125'. The first protrusion 135 can be in a triangular structure with an inclined surface and a vertical surface, the inclined surface is located on the proximal side, and the vertical surface is located on the distal side. Correspondingly, a second protrusion 127 is provided on the cutting knife 120, which protrudes downward and is configured to interact with the first protrusion 135. The second protrusion 127 can also be in a triangular structure with an inclined surface and a vertical surface, the inclined surface is located on the distal side, and the vertical surface is located on the proximal side. The interaction between the first protrusion 135 and the second protrusion 127 will be further described below.

[0041] In addition, the elongated body 131 of the secondary firing safety member 130 is also provided with a stepped portion at the proximal end. Figure 3As shown. The stepped portion includes, in sequence from the proximal side to the distal side, a first step portion 136 which is the shortest and is substantially horizontal, an inclined portion 137 which rises obliquely from the first step portion 136 toward the distal side and is connected between the first step portion 136 and the second step portion 138, a second step portion 138 which is greater in height than the first step portion 136 but still lower than the rest of the elongated body 131, and a shoulder 139 formed between the second step portion 138 and the rest of the elongated body 131. A through hole 128 formed through the side wall of the lower half shell 123 is also provided at a certain position in the lower half shell 123 which overlaps with the axial groove 125. A blocking pin 140 (e.g., a metal pin) is arranged in the through hole 128 in the wall of the lower half shell 123. In addition, the biasing device is configured to always be biased in a direction away from the inner side of the lower half shell 123 (i.e., away from the cutting knife) (i.e., Figure 6-13 The biasing means may be two compression springs 141 in a compressed state, and the blocking pin 140 will be clamped between the coils of the two springs 141 at both sides. During the operation of the cutting stapler 100, the blocking pin 140 accommodated in the through hole 128 of the lower half shell 123 can only move in a direction perpendicular to the axial direction (i.e., Figure 6-13 The blocking pin 140 can move in the vertical direction of the lower housing 123, but cannot move in the axial direction relative to the lower housing 123. The thickness of the blocking pin 140 is configured to be slightly less than or equal to the height difference between the first step portion 136 and the rest of the elongated body 131, but greater than the height difference between the second step portion 138 and the rest of the elongated body 131, that is, the height of the shoulder 139. Figure 7 As shown, the cutting knife 120 is also provided with a third protruding block 129 protruding downwards at the proximal side of the through hole 128. The third protruding block 129 may also be in a triangular configuration with an inclined surface and a vertical surface, wherein the inclined surface is located at the proximal side and the vertical surface is located at the distal side. The third protruding block 129 of the cutting knife 120 is substantially equal to the height of the second protruding block 127 protruding downwards. The blocking pin 140 will cooperate with the aforementioned stepped portion and the third protruding block 129 to prevent the cutting knife 120 from being fired again and moving in the distal direction after a firing, as will be described in detail later.

[0042] The above has been combined Figure 1-5 etc. describe the structure of the execution assembly of the cutting stapler 100. However, it should be noted that only the components related to the secondary firing safety mechanism of the cutting stapler 100 are described here. However, the execution assembly of the cutting stapler 100 may also include many other components in addition to the above components, and the structures and functions of these other components are known to those skilled in the art, and will not be described in detail here.

[0043] Next, the working mechanism of the secondary firing safety mechanism will be described in detail.

[0044] First, if Figure 6 , 7 As shown, in the initial state before the cutting stapler is used for the first time, the cutting knife 120 and its driving sleeve 121 are located at their proximal end positions in the housing, and the staple cartridge component 111 and the staple holder 112 are in an open state. At this time, the secondary firing safety element 130 is located at its distal end position P1 (see Figure 4 ), the second protrusion 127 of the cutting knife 120 is located on the proximal side of the first protrusion 135 of the secondary firing safety piece 130, the blocking pin 140 is biased downward by the compression spring 141 and retracted into the through hole 128 and rests on the first step portion 136 with the lowest height of the secondary firing safety piece 130, and the third protrusion 129 of the cutting knife 120 is located on the proximal side of the blocking pin 140.

[0045] Next, if Figure 8 , 9 As shown, as the cutting knife 120 is driven by its driving sleeve 121 to move further in the distal direction, the second protrusion 127 of the cutting knife 120 passes over the first protrusion 135 of the secondary firing safety member 130, and the third protrusion 129 of the cutting knife 120 passes between the two compression springs 141 above the blocking pin 140 and also passes over the first protrusion 135 of the secondary firing safety member 130, thereby the cutting knife 120 reaches its distal end position. Note that since the inclined surface of the first protrusion 135 is located on the proximal side, when the cutting knife 120 moves from the proximal side to the distal side, the second protrusion 127 and the third protrusion 129 that pass successively press the inclined surface of the first protrusion 135 downward, so that the cantilever arm 134 and the first protrusion 135 retract downward to allow the second protrusion 127 and the third protrusion 129 to pass. The cutting knife 120 located at its most distal position can perform a cutting operation on the tissue to be cut that is clamped by the closed staple cartridge component 111 and the staple anvil 112 at this time.

[0046] Next, after the cutting operation is complete, the operator will pull the cutting knife 120 back proximally. Fig.10 , 11 The schematic diagram shows the state when the cutting knife 120 is pulled back to just contact the secondary firing safety piece 130. At this time, the vertical surface of the second protruding block 127 of the cutting knife 120 just abuts against the vertical surface of the first protruding block 135 of the secondary firing safety piece 130, the third protrusion 129 of the cutting knife 120 is just located above the blocking pin 140, the blocking pin 140 is located on the first step 136, and the secondary firing safety piece 130 is still located at its distal end position P1.

[0047] Finally, as the operator further pulls the cutting knife 120 back proximally, the secondary firing safety member 130 whose first protrusion 135 abuts against the second protrusion 127 of the cutting knife 120 will move proximally together with the cutting knife 120 until the secondary firing safety member 130 reaches its most proximal end position P2, as shown in FIG. Fig.12 , 13 In this process, the inclined portion 138 (see Figure 3 ) will first pass under the blocking pin 140 biased downward by the compression spring 141, and the inclined portion 138 passed gradually will compress the compression spring 141 upward, so that the blocking pin 140 moves upward until the second step portion 138 with the largest height is located below the blocking pin 140 and the blocking pin 140 at least partially extends from the through hole 128 toward the inner side of the lower half shell 123. Thereafter, the operator withdraws the cutting stapler 100 from the operated part of the patient.

[0048] Thus, the firing of the cutting stapler 100 is completed. Since the cutting stapler 100 is disposable, the used cutting stapler 100 should be discarded. If the operator accidentally reuses the cutting stapler 100 that has been fired once, the cutting knife 120 will be Fig.13 The state shown moves toward the distal side. Fig.13 After the shown state moves slightly toward the distal side, the 3rd projection 129 of the cutting knife 120 will contact the blocking pin 140 extending from the through hole 128 to the inner side of the lower half housing 123. The blocking pin 140 extending out has stopped the 3rd projection 129 of the cutting knife 120 from passing through, thereby stopping the cutting knife 120 from moving further toward the distal side.

[0049] By utilizing the secondary firing safety mechanism of the cutting stapler 100 of the present invention, the secondary firing of the cutting knife 120 can be reliably prevented, thereby avoiding the situation where only the cutting knife cuts the tissue but fails to suture the tissue incision.

[0050] Next, the resetting of the secondary firing safety mechanism will be described in detail.

[0051] Before the cutting stapler leaves the factory for sale or medical use, it needs to be tested for firing, and after the firing test, the secondary firing safety mechanism needs to be reset, otherwise the cutting stapler cannot be used for secondary firing after being fired once in the test. The cutting stapler 100 according to the present invention is fired once by the manufacturer according to the above process before leaving the factory, so that the secondary firing safety mechanism of the cutting stapler 100 will be in the following state. Fig.13Afterwards, the manufacturing personnel reaches into a specially made hook (not shown) from the corresponding adjustment opening on the sleeve to hook the cantilever arm 134 of the secondary firing safety member 130, and pulls the cantilever arm 134 outward to release the abutment between the first protrusion 135 on the cantilever arm 134 and the second protrusion 127 of the cutting knife 120. After the abutment is released, the manufacturing personnel also pulls the cantilever arm 134 distally to move the secondary firing safety member 130 to its distal end position P1. In this way, the secondary firing safety member 130 will be restored to the state as shown in FIG. Figure 6 , 7 The initial state is that the second protrusion 127 of the cutting blade 120 is located proximal to the first protrusion 135 of the secondary firing safety member 130, the blocking pin 140 is biased downward into the through hole 128 by the compression spring 141 and rests on the first step 136 of the secondary firing safety member 130, and the third protrusion 129 of the cutting blade 120 is located proximal to the blocking pin 140. After the secondary firing safety mechanism is reset, the cutting stapler 100 can be fired and used again.

[0052] The secondary firing safety mechanism of the cutting stapler 100 according to the present invention can simply and reliably reset the secondary firing safety mechanism, and is not likely to cause damage to related components of the cutting stapler during the resetting process.

[0053] While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments.The scope of the following claims is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures and functions.

Claims

1. A secondary firing safety mechanism for a cutting stapler, the cutting stapler (100) being provided with a cutting knife (120) arranged in a hollow shell, the cutting knife (120) being configured to be able to move proximally and distally along the axial direction of the shell, characterized in that: The secondary firing safety mechanism is provided with a secondary firing safety piece (130) which is arranged on the outer peripheral side of the shell and can move in conjunction with the movement of the cutting knife (120), and a blocking pin (140) which is arranged in a through hole (128) in the shell wall, wherein the blocking pin (140) is configured such that: during a primary firing process, the blocking pin (140) is biased away from the cutting knife (120) by a biasing member and does not protrude from the through hole (128) to the inside of the shell, so as to allow the cutting knife (120) to advance from the proximal side to the distal side and then withdraw from the distal side to the proximal side; when a secondary firing is desired, the secondary firing safety piece (130) pushes the blocking pin (140) against the biasing force of the biasing member, so that the blocking pin (140) at least partially protrudes from the through hole (128) to the inside of the shell, so as to prevent the cutting knife (120) from advancing from the proximal side to the distal side. The secondary firing safety element (130) comprises an elongated main body (131) extending in the axial direction of the housing, and the housing is provided with an axial groove (125) longer than the elongated main body (131) in the outer peripheral side wall, and the elongated main body (131) is configured to be accommodated on the outer peripheral side of the housing in a manner that it can slide along the axial groove (125) between a distal end position (P1) and a proximal end position (P2), The elongated body (131) of the secondary firing safety member (130) is provided with a cantilever arm (134) capable of moving perpendicularly to the axial direction under the action of an external force, and the cantilever arm (134) is provided with a first protrusion (135) at a free end thereof, and the first protrusion (135) is configured to protrude from an axial through groove (125') provided at the bottom of the axial groove (125) to the inside of the housing, and the cutting knife (120) is provided with a corresponding second protrusion (127). The elongated body (131) is provided with a stepped portion, which includes, in order from the proximal side to the distal side, a first step portion (136) with the lowest height, an inclined portion (137) which rises obliquely from the first step portion (136) toward the distal side and is connected between the first step portion (136) and the second step portion (138), and the second step portion (138) which is greater in height than the first step portion (136) but lower in height than the rest of the elongated body (131). The cutting knife (120) is provided with a third protrusion (129). When the secondary firing safety piece (130) is located at the distal end position (P1), the third protrusion (129) can pass over the blocking pin (140) so that the cutting knife (120) can move forward from the proximal side to the distal side and withdraw from the distal side to the proximal side; when the secondary firing safety piece (130) is located at the proximal end position (P2), the blocking pin (140) blocks the third protrusion (129) from passing through so as to block the cutting knife (120) from moving forward from the proximal side to the distal side.

2. The secondary firing safety mechanism for a cutting stapler according to claim 1, characterized in that: The first protrusion (135) of the secondary firing safety piece (130) is in a triangular structure with an inclined surface on the proximal side and a vertical surface on the distal side, and the second protrusion (127) of the cutting knife (120) is in a triangular structure with an inclined surface on the distal side and a vertical surface on the proximal side.

3. The secondary firing safety mechanism for a cutting stapler according to claim 2, characterized in that: The first projection (135) and the second projection (127) are configured such that: When the cutting knife (120) moves forward from the proximal side to the distal side during a single firing process, the inclined surface of the second protrusion (127) of the cutting knife (120) presses the inclined surface of the first protrusion (135) of the secondary firing safety member (130) toward the axial through slot (125'), so that the first protrusion (135) retracts toward the axial through slot (125') to allow the cutting knife (120) to pass through; and When the cutting knife (120) is withdrawn from the distal side to the proximal side after being fired once, the vertical surface of the second protrusion (127) of the cutting knife (120) abuts against the vertical surface of the first protrusion (135) of the secondary firing safety piece (130), so that the secondary firing safety piece (130) moves toward the proximal side together with the cutting knife (120) until the secondary firing safety piece (130) reaches its proximal end position (P2).

4. The secondary firing safety mechanism for a cutting stapler according to claim 1, characterized in that: When the secondary firing safety element (130) is located at the distal end position (P1), the first step portion (136) with the lowest height is located below the blocking pin (140), so that the biasing member biases the blocking pin (140) away from the cutting knife (120) so that the blocking pin (140) does not protrude from the through hole (128) to the inside of the shell.

5. The secondary firing safety mechanism for a cutting stapler according to claim 1, characterized in that: When the secondary firing safety element (130) is located at the proximal end position (P2), a second step portion (138) having a height greater than the first step portion (136) but lower than the rest of the elongated body (131) is located below the blocking pin (140) to push the blocking pin (140) against the biasing force of the biasing member, so that the blocking pin (140) at least partially protrudes from the through hole (128) to the inside of the shell, thereby preventing the cutting knife (120) from moving from the proximal side to the distal side.

6. The secondary firing safety mechanism for a cutting stapler according to any one of claims 1 to 5, characterized in that: The secondary firing safety mechanism of a cutting stapler that has been fired once can be reset as follows: a cantilever arm (134) of the secondary firing safety piece (130) is hooked with a hook through an adjustment opening on an outer sleeve of the cutting stapler, the cantilever arm (134) is pulled outward to release the abutment between the first protrusion (135) of the secondary firing safety piece (130) and the second protrusion (127) of the cutting knife (120), and then the cantilever arm (134) is pulled distally after the abutment is released to move the secondary firing safety piece (130) to its distal end position (P1).

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