Rotary cutting head, rotary cutting head assembly and rotary cutting volume reduction device

Abstract

This invention relates to the field of medical device technology, and discloses a rotary cutting head, a rotary cutting head assembly, and a rotary cutting volume reduction device. The rotary cutting head includes a head body. The head body has multiple rotary cutting sections extending from the proximal end to the distal end, arranged circumferentially around the head body. A groove is provided between adjacent rotary cutting sections. Each rotary cutting section includes a cutting blade, a front cutting surface located in front of the cutting blade, and a rear cutting surface located behind the cutting blade. The rotary cutting section also includes a depth-limiting groove located in front of the cutting blade. The depth-limiting groove includes a first inner surface and a second inner surface. The first inner surface serves as the front cutting surface, and the second inner surface is connected to the groove. The distance between the connection point of the first and second inner surfaces and the cutting blade is the depth of the depth-limiting groove. The depth of the depth-limiting groove is used to limit the maximum cutting depth. The depth-limiting groove can limit the cutting depth of the cutting blade, preventing excessive cutting depth and protecting the intima and media of the blood vessel wall, thus improving safety.

Description

Technical Field

[0001] This invention relates to the field of medical device technology, specifically to a rotary cutting head, a rotary cutting head assembly, and a rotary cutting and volume reduction device. Background Technology

[0002] Peripheral artery atherosclerosis and acute thromboembolism are important causes of limb ischemia and arterial stenosis. Related treatments require the use of medical devices such as dilating balloons, stents, and rotary cutting and volume reduction devices. Among them, rotary cutting and volume reduction devices can remove diseased plaques with a high-speed rotating blade, thereby restoring vascular patency.

[0003] The rotary cutting and volume reduction device in related technologies includes a catheter and a cutting head. The cutting head is driven and installed at the distal end of the catheter. The cutting head includes multiple cutting blades. The cutting head is driven to rotate at high speed and removes the lesion plaque through the cutting blades. However, in a clinical setting, the operator's experience is usually required to control the cutting depth. If not careful, the cutting depth may be too deep, which can easily damage the intima or even the media of the blood vessel wall when removing the lesion plaque, resulting in low safety. Summary of the Invention

[0004] This invention provides a rotary cutting head, a rotary cutting head assembly, and a rotary cutting volume reduction device to improve the control of the cutting depth of the rotary cutting head, avoid damage to the blood vessel wall, and improve safety.

[0005] In a first aspect, the present invention provides a rotary cutting head, comprising:

[0006] The cutter head body has multiple rotary cutting sections extending from the proximal end to the distal end. The multiple rotary cutting sections are arranged at intervals along the circumference of the cutter head body. A cutting groove is provided between two adjacent rotary cutting sections. Each rotary cutting section includes a cutting blade. In the rotation direction of the rotary cutting section, the rotary cutting section includes a front cutting surface provided on the front side of the cutting blade and a rear cutting surface provided on the rear side of the cutting blade.

[0007] The rotary cutting section includes a depth limiting groove disposed on the front side of the cutting edge. The depth limiting groove includes a first inner side and a second inner side that are connected and form an angle with each other. The first inner side is connected to the cutting edge and serves as the rake face. The second inner side is connected to the tool groove. The distance between the connection point of the first inner side and the second inner side and the cutting edge serves as the depth of the depth limiting groove. The depth of the depth limiting groove is used to limit the ultimate cutting depth.

[0008] Optionally, the cutting groove includes a first groove surface near the front cutting face and a second groove surface near the rear cutting face, and the second inner side surface of the depth-limiting groove serves as a transition surface connected to the first groove surface.

[0009] Optionally, the depth range of the depth limiting groove is 0.05 mm to 0.1 mm.

[0010] Optionally, the cutting blade has a front angle and a rear angle, the front angle having an angle range of 10° to 15° and the rear angle having an angle range of 7° to 12°.

[0011] Optionally, the cutting edge inclination angle ranges from 20° to 25°.

[0012] Optionally, the cutter head body is provided with a side suction part, which is located on one side of the proximal end of the rotary cutting part. The outer peripheral wall of the side suction part is provided with a plurality of side suction holes, and there is a gap between the side suction holes and the proximal end of the rotary cutting part.

[0013] Optionally, the outer diameter of the side suction part is D1, the maximum outer diameter of the rotary cutting part is D2, and the ratio of D2 to D1 is in the range of 1.05 to 1.1.

[0014] Secondly, the present invention provides a rotary cutting head assembly, including the aforementioned rotary cutting head, and further including an inner cutting head, wherein the cutting head body has an inner cavity, and the inner cutting head is coaxially disposed in the inner cavity.

[0015] Optionally, the inner blade is provided with an inner cutting hole corresponding to the side suction hole.

[0016] Thirdly, the present invention provides a rotary cutting and volume reduction device, including the above-mentioned rotary cutting head assembly.

[0017] Beneficial effects:

[0018] The present invention provides a rotary cutting head, comprising: a cutting head body. The cutting head body has a plurality of rotary cutting portions extending from the proximal end to the distal end, the plurality of rotary cutting portions being arranged at intervals along the circumference of the cutting head body, a cutting groove being provided between two adjacent rotary cutting portions, each rotary cutting portion including a cutting edge, and in the rotation direction of the rotary cutting portion including a front cutting face and a rear cutting face provided behind the cutting edge, the rotary cutting portion including a depth limiting groove provided in front of the cutting edge, the depth limiting groove including a first inner surface and a second inner surface connected to each other and forming an included angle, the first inner surface being connected to the cutting edge and serving as the front cutting face, the second inner surface being connected to the cutting groove, the distance between the connection point of the first inner surface and the second inner surface and the cutting edge serving as the depth of the depth limiting groove, the depth of the depth limiting groove being used to limit the ultimate cutting depth.

[0019] During use, the blade body rotates around the central axis, and multiple rotary cutting sections rotate synchronously. The cutting edge can remove lesions and plaques, and the groove between two adjacent rotary cutting sections can be used to remove the removed lesions and plaques. Since the depth of the depth limiting groove can limit the ultimate cutting depth, the cutting depth of the cutting edge can be prevented from being too deep by setting the depth of the depth limiting groove, thereby protecting the intima and media of the blood vessel wall and improving safety. Attached Figure Description

[0020] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0021] Figure 1 This is a schematic diagram of the structure of the rotary cutting head according to an embodiment of the present invention;

[0022] Figure 2 for Figure 1 A schematic diagram of the cross-sectional structure of the rotary cutting head shown;

[0023] Figure 3 for Figure 1 The front view of the rotary cutting head shown;

[0024] Figure 4 for Figure 3 A magnified view of a section at point A in the middle;

[0025] Figure 5 This is a reference diagram showing the usage state of the rotary cutting head according to an embodiment of the present invention;

[0026] Figure 6 This is a schematic diagram of the rotary cutting section and the side suction section according to an embodiment of the present invention;

[0027] Figure 7 This is a schematic diagram of the rotation path of the rotary cutting section according to an embodiment of the present invention;

[0028] Figure 8 This is another cross-sectional structural diagram of the rotary cutting head according to an embodiment of the present invention;

[0029] Figure 9 This is a schematic diagram of the blade inclination angle of the rotary cutting section according to an embodiment of the present invention;

[0030] Figure 10 This is a schematic diagram of the rotary cutting and volume reduction device according to an embodiment of the present invention;

[0031] Figure 11 This is a schematic diagram of the internal cutting head structure according to an embodiment of the present invention;

[0032] Figure 12 This is a side view of the inner blade of an embodiment of the present invention;

[0033] Figure 13 This is a schematic diagram of the structure of the first embodiment of the side suction hole of the present invention;

[0034] Figure 14 for Figure 13 A schematic diagram of the cross-sectional structure of the side suction hole;

[0035] Figure 15 This is a schematic diagram of the structure of a second embodiment of the side suction hole of the present invention;

[0036] Figure 16 for Figure 15 A schematic diagram of the cross-sectional structure of the side suction hole;

[0037] Figure 17 This is a schematic diagram of the third embodiment of the side suction hole of the present invention;

[0038] Figure 18 for Figure 17 A schematic diagram of the structure of the middle side suction hole from another angle;

[0039] Figure 19 This is a schematic diagram of the fourth embodiment of the side suction hole of the present invention;

[0040] Figure 20 This is a cross-sectional structural diagram of the rotary cutting and volume reduction device according to an embodiment of the present invention;

[0041] Figure 21 for Figure 20 A magnified view of a section at point B in the middle;

[0042] Figure 22 for Figure 20 A magnified view of a section at point C;

[0043] Figure 23 This is a schematic diagram of the transmission torque tube according to an embodiment of the present invention;

[0044] Figure 24 This is an exploded view of the rotary cutting and volume reduction device according to an embodiment of the present invention;

[0045] Figure 25 This is a schematic diagram of the embedded segment and the reinforcing layer in an embodiment of the present invention.

[0046] Explanation of reference numerals in the attached figures:

[0047] 1. Blade body; 11. Rotary cutting section; 111. Cutting edge; 112. Front cutting face; 113. Back cutting face;

[0048] 114. Depth-limiting groove; 115. Cutting groove; 1151. First groove surface; 1152. Second groove surface; 1153. Transition surface;

[0049] 12. Side suction section; 121. Inner cavity; 122. Side suction hole; 1221. First side cut wall; 12211. First peak; 12212. First trough; 1222. Second side cut wall; 12221. Second peak; 12222. Second trough; 1223. First arc-shaped wall; 1224. Second arc-shaped wall; 1225. Third arc-shaped wall; 1226. Fourth arc-shaped wall;

[0050] 13. Guidewire lumen;

[0051] 2. Inner cutting head; 21. Inner cutting hole; 211. First inner cutting wall; 212. Second inner cutting wall; 22. Embedded section; 221. Through hole; 23. Protruding ring; 201. First limiting surface; 24. Limiting ring;

[0052] 3. Catheter; 31. Inner layer; 32. Reinforcing layer; 33. Outer layer;

[0053] 4. Torque transmission tube; 41. Double-layer metal spring tube; 411. First metal winding wire; 412. Second metal winding wire; 42. Winding spring; 43. Protruding structure; 431. Protrusion; 432. Annular flange; 401. Second limiting surface;

[0054] 5. Scrolling component. Detailed Implementation

[0055] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0056] The following is combined with Figures 1 to 25 The following describes embodiments of the present invention.

[0057] like Figure 1 and Figure 2 As shown, an embodiment of the present invention provides a rotary cutting head for a rotary cutting volume reduction device. The rotary cutting volume reduction device includes a rotary cutting head, an outer tube assembly, and a torque transmission tube. The torque transmission tube is driven to be disposed inside the outer tube assembly. The distal end of the torque transmission tube passes through the distal port of the outer tube assembly and is connected to the rotary cutting head. The torque transmission tube is used to drive the rotary cutting head to rotate relative to the outer tube assembly. The rotary cutting head includes:

[0058] The cutter head body 1 is provided with a plurality of rotary cutting portions 11 extending from the proximal end to the distal end. The plurality of rotary cutting portions 11 are arranged at intervals along the circumference of the cutter head body 1. A cutting groove 115 is provided between two adjacent rotary cutting portions 11. Each rotary cutting portion 11 includes a cutting blade 111. In the rotation direction of the rotary cutting portion 11, the rotary cutting portion 11 includes a front cutting surface 112 provided on the front side of the cutting blade 111 and a rear cutting surface 113 provided on the rear side of the cutting blade 111.

[0059] The rotary cutting section 11 includes a depth-limiting groove 114 located in front of the cutting blade 111. The depth-limiting groove 114 includes a first inner surface and a second inner surface connected and forming an angle with each other. The first inner surface is connected to the cutting blade 111 and serves as the front cutting surface 112. The second inner surface is connected to the cutting groove 115. The distance between the connection point of the first and second inner surfaces and the cutting blade 111 is the depth of the depth-limiting groove. The depth of the depth-limiting groove 114 is used to limit the ultimate cutting depth. In use, the blade body 1 rotates around its central axis, and multiple rotary cutting sections 11 rotate synchronously. The cutting blade 111 can remove lesion plaques, and the cutting groove 115 between two adjacent rotary cutting sections 11 can be used to remove the removed lesion plaques. Because the depth of the depth-limiting groove 114 can limit the ultimate cutting depth, the cutting depth of the cutting blade 111 can be prevented from being too deep by setting the depth of the depth-limiting groove 114, thereby protecting the intima and media of the blood vessel wall and improving safety.

[0060] Specifically, such as Figure 5 As shown, during the rotation of the blade body 1, each cutting edge 111 cuts off a certain amount of lesion plaque with each rotation, thus removing the lesion plaque layer by layer through the cutting edge 111. During each rotation of the cutting edge 111, the cutting edge 111 first contacts and cuts the lesion plaque, and then the front cutting surface 112 contacts the lesion plaque. As the cutting progress of the cutting edge 111, the removed lesion plaque gradually enters the depth limiting groove 114. When the cutting depth of the cutting edge 111 reaches its limit, the lesion plaque will fill the depth limiting groove 114. Therefore, the removed lesion plaque near the cutting edge 111 will affect the cutting edge 111's continued contact with uncut lesion plaque or the inner wall of the blood vessel. Thus, the depth of the depth limiting groove 114 limits the limit cutting depth of the cutting edge 111, while also protecting the inner wall of the blood vessel.

[0061] It should be noted that as the depth of the limiting groove increases, the maximum cutting depth of the cutting blade 111 per revolution also increases. Furthermore, in cases where plaque and thrombus coexist on the inner wall of a blood vessel, the cutting blade 111 provided in this embodiment can also remove the thrombus from the inner wall of the blood vessel.

[0062] In this embodiment, the cutting edge 111, the front cutting face 112, and the rear cutting face 113 all extend from the proximal end to the distal end of the cutter head body 1. The depth limiting groove 114 also extends from the proximal end to the distal end, and its extension direction is consistent with that of the front cutting face 112. The proximal end and the distal end are defined according to the distance between the structure and the operator. The end closer to the operator is defined as the proximal end, and the end farther from the operator is defined as the distal end. When describing two or more structures, the relative proximal ends and relative distal ends of the two or more structures are defined in the same way to facilitate a clear explanation of the positional relationship.

[0063] like Figure 2 , Figure 3 and Figure 4 As shown, in this embodiment, the cutting groove 115 includes a first groove surface 1151 near the front cutting face 112 and a second groove surface 1152 near the rear cutting face 113. The second inner side of the depth-limiting groove 114 serves as a transition surface 1153 connected to the first groove surface 1151. The cutting groove 115 extends from the proximal end to the distal end. The cutting groove 115 is used to remove cut-off lesions or thrombi, preventing lesions or thrombi from obstructing the cutting edge 111 from performing the cutting action. Machining the transition surface 1153 on the first groove surface 1151 and forming the depth-limiting groove 114 with the front cutting face 112 can reduce the machining difficulty. The width of the front cutting face 112 is the depth of the depth-limiting groove 114.

[0064] like Figure 2 As shown, in this embodiment, the depth range of the depth limiting groove 114 is 0.05mm to 0.1mm. Figure 2 The depth of the depth limiting groove 114 is shown, and the dimension of the depth is defined as S, which ranges from 0.05 mm to 0.1 mm. The sum of the thickness of the intima and media of a healthy blood vessel is typically no more than 0.5 mm, while the thickness of the lesion area increases to 0.6 mm to 1.0 mm, where the thickness of the lesion plaque is 0.1 mm to 0.5 mm. Therefore, the depth range of the depth limiting groove 114 is set to 0.05 mm to 0.1 mm. Specifically, if the depth of the depth limiting groove 114 is less than 0.05 mm, the cutting depth of the cutting blade 111 will be too shallow. Even when the thickness of the lesion plaque is 0.1 mm, the cutting blade 111 will need to cut layer by layer multiple times to remove the lesion plaque, resulting in poor removal efficiency. If the depth of the depth limiting groove 114 is greater than 0.1 mm, when the thickness of the lesion plaque is 0.1 mm, the cutting depth of the cutting blade 111 will be too deep, which can easily cause damage to the intima of the blood vessel wall. Therefore, setting the depth range of the depth limiting groove 114 to 0.05 mm to 0.1 mm can ensure both the removal efficiency of the cutting blade 111 and safety. Preferably, the depth of the depth limiting groove 114 can be set to 0.1 mm. This setting can satisfy the requirement of efficient removal of only the lesion plaque while avoiding damage to the blood vessel intima caused by excessive cutting depth.

[0065] It should be noted that, because vascular tissue has good elasticity and deformability, it is easy to deviate outside the blade groove under friction. Therefore, when the depth of the depth limiting groove 114 is set to 0.1mm, after the cutting blade 111 removes the lesion plaque, even if the inner wall of the vascular tissue is in slight contact with the cutting blade 111, it can deviate outside the depth limiting groove 114 through its own elasticity and deformability, and will not cause overcutting.

[0066] like Figure 2 and Figure 5 As shown, in this embodiment, the cutting blade 111 has a front angle and a rear angle, with the front angle ranging from 10° to 15° and the rear angle ranging from 7° to 12°.

[0067] The rake angle refers to the angle between the rake face 112 and the cutting plane. The cutting plane refers to the plane passing through the cutting point and perpendicular to the surface of the blood vessel wall, for example... Figure 5 The diagram shown illustrates the cutting process. Figure 5 The shaded area on the right represents the inner wall of the blood vessel. The cutting plane is a plane passing through the cutting point and perpendicular to the inner wall of the blood vessel. The cutting plane also passes through the central axis of the blade body 1. The angle of the front angle is defined as γ, which ranges from 10° to 15°. If the angle of the front angle is less than 10°, the cutting edge 111 is relatively blunt, requiring a larger cutting force, making the cutting action closer to crushing the lesion plaque. This can be used to remove fibrotic or calcified plaques, but the efficiency is low, and it is easy to produce irregularly shaped debris. If the angle of the front angle is greater than 15°, the cutting edge 111 is relatively sharp, requiring a smaller cutting force, and the cutting effect on thrombi or lipid plaques is better, but it is easy to over-cut, causing damage or even peeling of the vascular intima. Therefore, the angle of the front angle is set to a range of 10° to 15°, so that the sharpness of the cutting edge 111 is moderate, which can meet the requirements for cutting various lesion plaques, ensure cutting efficiency, and avoid excessive sharpness that could damage the vascular intima, thus ensuring safety. Preferably, the angle of the front angle is set to 12.5°.

[0068] The posterior angle refers to the angle between the posterior blade 113 and the inner wall surface of the blood vessel, for example... Figure 5The vertical plane in the shaded area on the right shows the surface of the inner wall of the blood vessel. The angle of the back angle is defined as α, which ranges from 7° to 12°. If the back angle is less than 7°, the back blade 113 will rub against the inner wall of the blood vessel, causing thermal and mechanical damage. If the back angle is greater than 12°, although it can avoid contact between the back blade 113 and the inner wall of the blood vessel, it will weaken the mechanical strength of the cutting edge 111, making it prone to breakage when the cutting edge 111 removes hard plaques. It will also increase cutting vibration. Therefore, setting the back angle range to 7° to 12° can both avoid continuous friction between the back blade 113 and the blood vessel wall and ensure the strength of the cutting edge 111. Preferably, the back angle is set to 10°.

[0069] like Figure 6 As shown, in this embodiment, the blade inclination angle of the cutting edge 111 ranges from 20° to 25°. The blade inclination angle refers to the angle between the cutting edge 111 and the central axis. The cutting edge 111 is inclined in the direction of rotation from its proximal end to its distal end. During the operation of the cutting edge 111, the rotary cutting section 11, in conjunction with the blade groove 115, can achieve the functions of active traction and efficient removal of the cut tissue. Figure 6 The dashed line in the diagram indicates the central axis of the cutter head body 1. The angle of the blade inclination is defined as λ, which ranges from 20° to 25°. If the blade inclination angle is less than 20°, the efficiency of removing the cut tissue will be too low, affecting the cutting effect of the cutting blade 111. If the blade inclination angle is greater than 25°, the blade will be too sharp, increasing the risk of damage to the blood vessel wall. Therefore, to balance the efficiency of removing the cut tissue, the cutting efficiency, and the safety, the blade inclination angle is set to 20° to 25°. Preferably, the blade inclination angle is set to 22.5°.

[0070] like Figure 1 , Figure 7 and Figure 8 As shown, in this embodiment, the blade body 1 is provided with a side suction section 12, which is located on one side of the proximal end of the rotary cutting section 11. The outer peripheral wall of the side suction section 12 is provided with a plurality of side suction holes 122, and there is a gap between the side suction holes 122 and the proximal end of the rotary cutting section 11. The side suction holes 122 of the side suction section 12 are used to suck up the cut lesion plaques and thrombi and discharge them from the body in conjunction with the catheter 3. Combined with the cooperation of the rotary cutting section 11 and the blade groove 115 mentioned above, the efficiency of discharging lesion plaques and thrombi can be improved.

[0071] like Figure 7 and Figure 8As shown, in this embodiment, the outer diameter of the side suction section 12 is D1, and the maximum outer diameter of the rotary cutting section 11 is D2. The ratio of D2 to D1 ranges from 1.05 to 1.1. The side suction section 12 can be configured as a tubular structure. The maximum outer diameter of the rotary cutting section 11 refers to the maximum area that the rotary cutting section 11 rotates through in the radial direction of the blade body 1. It can be understood that the rotation path at the maximum outer diameter of the rotary cutting section 11 is circular. For ease of comparison, the outer diameter of the side suction section 12 is defined as D1, and the maximum outer diameter of the rotary cutting section 11 is defined as D2. D1 is smaller than D2, thereby maximizing the removal of lesions and thrombi while ensuring the suction efficiency of the side suction port 122.

[0072] For example, if the inner diameter of the blood vessel is set to D3, the larger the size of the cutting part 11 D2 is and the closer it is to D3, the larger the area of ​​lesion plaque and thrombus will be removed. When D1 is equal to D2, the gap between the side suction port 122 and the inner wall of the blood vessel will be too small, which is not conducive to lesion plaque and thrombus passing through the gap and entering the side suction port 122. Therefore, setting D1 to be less than D2 can ensure that there is a sufficient gap between the side suction port 122 and the inner wall of the blood vessel, thereby improving the suction efficiency of the side suction port 122 for lesion plaque and thrombus.

[0073] Furthermore, the ratio of D2 to D1 is set to a range of 1.05 to 1.1. If the ratio of D2 to D1 is greater than 1.1, the size of the side suction section 12 will be too small, which will also reduce the suction efficiency. If the ratio of D2 to D1 is less than 1.05, the gap between the side suction section 12 and the inner wall of the blood vessel will be too small, which is not conducive to the suction of lesions, plaques and thrombi. Therefore, setting the ratio of D2 to D1 to a range of 1.05 to 1.1 greatly ensures the suction efficiency while ensuring that the cutting section 11 can remove lesions, plaques and thrombi on the inner wall of the blood vessel to the maximum extent. Preferably, the ratio of D1 to D2 is set to 1.05. In addition, as an optional embodiment, the size of D1 is 3.2 mm and the size of D2 is 3.3 mm.

[0074] Based on this, the applicant integrated the setting parameters of the above structures to obtain the parameter range shown in Table 1, as well as the preferred parameter values. The rotary cutting head manufactured using the above parameter range or preferred parameters has the advantages of high cutting efficiency, high removal efficiency and high safety.

[0075] Table 1: Parameter Names, Parameter Ranges, and Recommended Values

[0076]

[0077] like Figure 9 As shown, in this embodiment, the blade body 1 is provided with a guide wire cavity 13 that runs through the central axis. The guide wire can be inserted through the opening of the guide wire cavity 13 to facilitate the delivery of the blade body 1 to the corresponding lesion location.

[0078] like Figure 10 and Figure 11 As shown, this embodiment provides a rotary cutting head assembly, including the above-mentioned rotary cutting head, and also includes an inner cutting head 2. The cutting head body 1 is provided with an inner cavity 121, and the inner cutting head 2 is coaxially disposed in the inner cavity 121.

[0079] The blade body 1 of the rotary cutting head assembly in this embodiment has the same composition, connection relationship and beneficial effects as the blade body 1 of the rotary cutting head described above, and will not be repeated here. The inner blade 2 can be used to further cut and subdivide the lesion plaques and thrombi in the suction side suction section 12, thereby improving the efficiency of removing lesion plaques and thrombi.

[0080] In this embodiment, the inner blade head 2 is provided with an inner incision hole 21 corresponding to the side suction hole 122. The rotary cutting head can rotate relative to the inner blade head 2. When the inner walls of the side suction hole 122 and the inner incision hole 21 move relative to each other, they have the function of shearing lesions and thrombi. For example, when the rotary cutting head rotates counterclockwise, the inner wall of the side suction hole 122 facing counterclockwise continuously approaches the inner wall of the inner incision hole 21 facing clockwise, thereby further cutting and subdividing the lesions and thrombi, thereby subdividing larger lesions and thrombi into smaller plaques, so that they can be discharged from the body through the side suction hole 122 and the inner incision hole 21. Specifically, the inner cavity 121 is provided on the side suction part 12, and the inner blade head 2 is a tubular structure. The inside of the inner blade head 2 is a suction chamber. The suction chamber can provide suction force through negative pressure, thereby attracting lesions and thrombi free in blood vessels through the inner incision hole 21 and the side suction hole 122.

[0081] It should be noted that the naming of the inner cutter head 2 in this embodiment is defined according to its relative position to the side suction part 12. The side suction part 12 is located on the outer side, and the inner cutter head 2 is located on the inner side. Based on the definition of the inner cutter head 2, the inner cutting hole 21 and the first inner cutting wall and the second inner cutting wall mentioned below are also defined in this way.

[0082] In this embodiment, the outer wall of the side suction part 12 is provided with a plurality of side suction holes 122, and the side wall of the inner blade 2 is provided with an inner cutting hole 21 corresponding to the side suction hole 122. The inner wall of the side suction hole 122 is set as a plane or an inclined surface extending obliquely towards the inner cutting hole 21.

[0083] During operation, the blade body 1 rotates relative to the inner blade 2 around its central axis. The rotary cutting section 11 of the blade body 1 can remove the lesion plaque. The side suction port 122 of the blade body 1 attracts the cut lesion plaque and thrombus, thereby expelling the lesion plaque and thrombus from the body. During this process, since the inner blade 2 is provided with an inner cutting port 21 corresponding to the side suction port 122, when the side suction port 122 rotates relative to the inner cutting port 21, the relative movement of the inner walls of the side suction port 122 and the inner cutting port 21 has a shearing effect on the lesion plaque and thrombus, which can further cut and subdivide the lesion plaque and thrombus. When the side suction port 122... When the inner wall is flat, the lesion plaque and thrombus can be further subdivided by squeezing and crushing. When the inner wall of the side suction port 122 is inclined, the inner wall of the side suction port 122 has a sharp edge, which can cut the lesion plaque and thrombus during rotation. Then, the inner wall of the side suction port 122 and the inner wall of the inner incision port 21 move relative to each other to shear. Through the cutting of the side suction port 122 and the shearing of the side suction port 122 and the inner incision port 21, the volume of the lesion plaque and thrombus can be greatly reduced, so that the thrombus is broken and refined, improving the efficiency of thrombus removal and avoiding thrombus blockage of the catheter 3.

[0084] It should be noted that the rotary cutting head assembly of this embodiment is suitable for installation at the distal end of the catheter 3 of the rotary cutting and volume reduction device. The catheter 3 can provide negative pressure to the inner cutting head 2 of the rotary cutting head assembly, thereby drawing the lesion plaque and thrombus into the catheter 3 through the side suction port 122 and the inner incision port 21. In addition, setting the side suction port 122 as an inclined plane is more suitable for shearing and subdividing fibrous and tough thrombi.

[0085] In this embodiment, both the side suction part 12 and the inner blade head 2 can be configured as tubular structures. The inner blade head 2 is installed in the inner cavity 121 of the side suction part 12, and the outer wall of the inner blade head 2 rotates and engages with the inner wall of the side suction part 12. When the side suction hole 122 rotates through the inner cutting hole 21, the inner walls of the side suction hole 122 and the inner cutting hole 21 move relative to each other and have a shearing effect, thereby further breaking down and subdividing the lesion plaque and thrombus.

[0086] like Figure 10 As shown, in this embodiment, the cutter head body 1 is adapted to rotate about its central axis in a first direction or a second direction opposite to the first direction. The side suction part 12 has a first side cutting wall 1221 facing the first direction and a second side cutting wall 1222 facing the second direction. The inner cutting hole 21 has a first inner cutting wall 211 facing the first direction and a second inner cutting wall 212 facing the second direction. The first direction can be either clockwise or counterclockwise, and the second direction can be either clockwise or counterclockwise. The rotation direction of the cutter head body 1 can be determined according to the orientation of the cutting edge 111 of the rotary cutting part 11, for example... Figure 10The cutting edge 111 of the blade body 1 shown faces counterclockwise, which is defined as the first direction. When the blade body 1 rotates counterclockwise around the central axis, the first side cutting wall 1221 rotates simultaneously in the counterclockwise direction. When the first side cutting wall 1221 passes the second inner cutting wall 212, the first side cutting wall 1221 and the second inner cutting wall 212 jointly cut the lesion plaque and thrombus to further subdivide the lesion plaque and thrombus.

[0087] It should be noted that the above example of the blade body 1 rotating counterclockwise is only for illustration. If the cutting edge 111 of the blade is facing clockwise, the blade body 1 can rotate clockwise. When the second side cutting wall 1222 moves clockwise and passes the first inner cutting wall 211, the relative movement of the second side cutting wall 1222 and the first inner cutting wall 211 can also cut the lesion plaque and thrombus.

[0088] like Figure 11 and Figure 12 As shown, in this embodiment, both the first inner incision wall 211 and the second inner incision wall 212 have at least one arc-shaped surface, thereby creating a shear angle between the first side incision wall 1221 and the second inner incision wall 212, and a shear angle between the second side incision wall 1222 and the first inner incision wall 211. Compared to the squeezing and crushing caused by the mutual movement of two parallel planes, this arrangement can improve the efficiency of shearing lesion plaques and thrombi, thereby improving the efficiency of removing lesion plaques and thrombi.

[0089] In a preferred embodiment, the first inner incision wall 211 and the second inner incision wall 212 are wavy in shape, and the first inner incision wall 211 and the second inner incision wall 212 have multiple continuous arcuate surfaces. This configuration can further improve the shearing effect and further improve the efficiency of shearing lesion plaques and thrombi.

[0090] In one embodiment, the line connecting the two opposite ends of the first side cutting wall 1221 forms an angle with the axial direction of the blade body 1, the angle ranging from 0° to 25°. The two opposite ends of the first side cutting wall 1221 refer to the proximal and distal ends of the first side cutting wall 1221, or the overall extension direction of the first side cutting wall 1221. When the angle between the line connecting the proximal and distal ends of the first side cutting wall 1221 and the axial direction of the blade body 1 is 0°, the first side cutting wall 1221 and the second inner cutting wall 212 move relative to each other and subdivide the lesion plaque and thrombus by compression and crushing. When the angle is greater than 0° and does not exceed 25°, the first side cutting wall 1221 and the second inner cutting wall 212 move relative to each other and subdivide the lesion plaque and thrombus by shearing and fragmentation, thereby subdividing the lesion plaque and thrombus more efficiently. Within the above angle range, the shearing efficiency increases with the increase of the angle, and it is particularly suitable for processing fibrous and tough thrombi.

[0091] In one embodiment, the line connecting the two opposite ends of the second side cutting wall 1222 forms an angle with the axial direction of the blade body 1, the angle ranging from 0° to 25°. The two opposite ends of the second side cutting wall 1222 refer to the proximal and distal ends of the second side cutting wall 1222, or the overall extension direction of the second side cutting wall 1222. When the angle between the line connecting the proximal and distal ends of the second side cutting wall 1222 and the axial direction of the blade body 1 is 0°, the second side cutting wall 1222 moves relative to the first inner cutting wall 211 and subdivides the lesion plaque and thrombus by compression and crushing. When the angle is greater than 0° but not exceeding 25°, the second side cutting wall 1222 and the second inner cutting wall 212 move relative to each other and subdivide the lesion plaque and thrombus by shearing and fragmentation, thereby subdividing the lesion plaque and thrombus more efficiently. Within the above angle range, the shearing efficiency increases with the increase of the angle, and it is particularly suitable for processing fibrous and tough thrombi.

[0092] like Figure 12 and Figure 13 As shown, in this embodiment, the side suction section 12 is provided with a plurality of side suction holes 122, which are arranged at intervals along the circumference of the side suction section 12. The inner blade head 2 is provided with a plurality of inner cutting holes 21, which are arranged at intervals along the circumference of the inner blade head 2. For example, the side suction section 12 is provided with three side suction holes 122, and the inner blade head 2 is provided with two inner cutting holes 21. When any side suction hole 122 and inner cutting hole 21 move relative to each other, they have a shearing effect. This arrangement can improve the suction efficiency and shearing efficiency for lesions, plaques and thrombi.

[0093] In one embodiment of this invention, two internal cutting holes 21 are symmetrically opened on the side wall of the inner blade head 2, and a plurality of side suction holes 122 are evenly spaced on the side wall of the side suction part 12.

[0094] like Figure 10 and Figure 13As shown, in this embodiment, the side suction hole 122 is provided with at least one first straight wall, and the inner cutting hole 21 is provided with at least one second straight wall opposite to the first straight wall. The first straight wall has an angle with the central axis of the blade body 1, and the angle range is 0° to 25°. The first straight wall serves as either the first side cutting wall 1221 or the second side cutting wall 1222, and correspondingly, the second straight wall serves as either the second inner cutting wall 212 or the first inner cutting wall 211. When the angle is 0°, the first and second straight walls move relative to each other and subdivide the lesion plaque and thrombus by squeezing and crushing. When the angle is greater than 0° and does not exceed 25°, the first and second straight walls move relative to each other and subdivide the lesion plaque and thrombus by shearing and crushing, thereby subdividing the lesion plaque and thrombus more efficiently. Within the above angle range, the shearing efficiency increases with the increase of the angle, and it is particularly suitable for processing fibrous and tough thrombi.

[0095] In a preferred embodiment, the side suction hole 122 has two oppositely arranged first straight walls, and the inner hole 21 is correspondingly provided with two second straight walls. The two first straight walls are respectively the first side cut wall 1221 and the second side cut wall 1222, and the two second straight walls are respectively the second inner cut wall 212 and the first inner cut wall 211.

[0096] As an optional implementation, both the side suction hole 122 and the inner incision hole 21 are designed as waist-shaped holes. The waist-shaped hole includes two opposing straight walls and two opposing arcuate walls. The two straight walls connect between the two opposing arcuate walls, forming a closed hole-like structure. The waist-shaped hole has two vertical centerlines, with the longer centerline defined as the long centerline. The first side incision wall 1221 and the second side incision wall 1222 of the side suction hole 122 are located on opposite sides of the long centerline, and the first side incision wall 1221, the second side incision wall 1222, and the long centerline are parallel to each other. Figure 6 The angle between the second side cutting wall 1222 and the central axis shown can be used to represent the angle between the long centerline of the side suction hole 122 and the central axis of the cutter body 1. The angle of this angle is defined as θ, and the range of θ is 0 to 25°.

[0097] like Figure 13 As shown, when the included angle is 0°, the first lateral incision wall 1221 and the second inner incision wall 212 move relative to each other and subdivide the lesion plaque and thrombus by squeezing and crushing.

[0098] like Figure 6 As shown, when the included angle is greater than 0° and does not exceed 25°, the first lateral cutting wall 1221 and the second inner cutting wall 212 move relative to each other and subdivide the lesion plaque and thrombus by shearing and fragmentation, thereby subdividing the lesion plaque and thrombus more efficiently. Within the above angle range, the shearing efficiency increases with the increase of the angle, and it is particularly suitable for treating fibrous and tough thrombi.

[0099] like Figure 13 and Figure 14 As shown, in the first embodiment of this example, in the radial direction of the side suction portion 12, the first side cutting wall 1221 and the second side cutting wall 1222 are inclined. The angle between the first side cutting wall 1221 and the outer wall of the side suction portion 12 is an acute angle, and the tip of the acute angle is defined as the cutting edge. The angle between the first side cutting wall 1221 and the inner wall of the side suction portion 12 is an obtuse angle, and the obtuse angle portion is defined as the shearing edge. The angle of the cutting edge is defined as θ1, and the value of θ1 ranges from 52° to 58°. The angle of the shearing edge is defined as θ2, and the value of θ2 ranges from 1° to 58°. With an angle of 23° to 137°, during the high-speed rotation of the side suction section 12 along the first or second direction, the cutting edge can initially cut the lesion plaque and thrombus. When the lesion plaque and thrombus enter between the first side cutting wall 1221 and the second inner cutting wall 212, or between the second side cutting wall 1222 and the first inner cutting wall 211, the shearing edge can work with the second inner cutting wall 212 or the first inner cutting wall 211 to further refine the lesion plaque and thrombus. This further refines the lesion plaque and thrombus through both cutting and shearing. This embodiment is more advantageous for treating fresh acute thrombi, resulting in better fragmentation and separation.

[0100] like Figure 15 and Figure 16 As shown, in the second embodiment of this example, the first side-cutting wall 1221 and the second side-cutting wall 1222 are inclined in the radial direction of the side suction part 12. The angle between the first side-cutting wall 1221 and the inner wall of the side suction part 12 is an acute angle, and the angle between the first side-cutting wall 1221 and the outer wall of the side suction part 12 is an obtuse angle. Following the above definition of the cutting edge and the shearing edge, compared with the previous embodiment, the sharpness of the shearing edge is improved in this embodiment. The angle of the shearing edge is defined as θ3, and the value of θ3 ranges from 28° to 32°. This can further improve the shearing effect and make it more suitable for subacute and chronic thrombosis.

[0101] like Figure 17 and Figure 18As shown, in the third embodiment of this example, the side suction hole 122 includes a first arc-shaped wall 1223 and a second arc-shaped wall 1224 arranged opposite each other in the axial direction. A first side-cutting wall 1221 and a second side-cutting wall 1222 are disposed between the first arc-shaped wall 1223 and the second arc-shaped wall 1224, and the first side-cutting wall 1221 and the second side-cutting wall 1222 are wavy. This configuration allows for multiple mating angles between the first side-cutting wall 1221 and the second inner cutting wall 212, and between the second side-cutting wall 1222 and the first inner cutting wall 211. In terms of cutting performance, segmented cutting reduces instantaneous cutting resistance, resulting in more complete cutting and fracture, preventing adhesion and blockage. Furthermore, the wave crests and troughs allow for periodic shearing of the chips, making it less likely to form continuous long chips. Simultaneously, wavy design of the first side-cutting wall 1221 and the second side-cutting wall 1222 enhances local turbulence and cleaning effects. The wavy cutting edge forms a micro-vortex zone, which promotes the flow and renewal of blood or rinsing fluid in the cutting area, improves chip removal, and reduces redeposition. To reduce the risk of negative pressure adsorption, the wavy surface of the blade creates micro-gaps between the sidewall and tissue during blade rotation, reducing the possibility of negative pressure adsorption onto the blood vessel wall and improving controllability and safety. This further improves the shearing effect and efficiency, and can further prevent catheter blockage. In addition, this design can reduce wear concentration points, improve blade life and edge retention. The crest and trough structure can serve as characteristic limits for structural reinforcement, increasing the tangential stiffness of the sidewall and reducing deformation and vibration at high speeds.

[0102] like Figure 17As shown, in an optional implementation, the first sidewall 1221 and the second sidewall 1222 are symmetrically arranged, with the peaks and troughs of the first sidewall 1221 and the second sidewall 1222 opposite to each other. For example, the first sidewall 1221 includes a first peak 12211 and a first trough 12212, and the second sidewall 1222 includes a second peak 12221 and a second trough 12222. The first peak 12211 and the second peak 12221 are opposite to each other, and the first trough 12211 is opposite to the second peak 12222. 2. Relative to the second trough 12222, the first sidewall 1221 can have multiple first peaks 12211, and the second sidewall 1222 can have multiple second peaks 12221. The distance between two adjacent first peaks is defined as wavelength λ1. The value of wavelength λ1 ranges from 0.3 to 0.5 times the outer diameter of the side suction part 12. Wavelength λ1 can affect the cutting pitch and fluid disturbance effect. Within the above range, the cutting pitch can be reasonably controlled and the fluid disturbance effect can be improved. In the radial direction of the sidewall, the distance between adjacent first peaks 12211 and first troughs 12212 is defined as amplitude A1. The value of amplitude A1 ranges from 0.15 to 0.3 times the outer diameter of the side suction part 12. Amplitude A1 can affect the cutting depth change. Within the above value range, the cutting depth can be reasonably controlled. The fillet radius of the first wave peak 12211 is defined as r1, with a value ranging from 0.03 mm to 0.1 mm. If r1 is less than 0.03 mm, it will lead to stress concentration and easily damage the vascular intima. If r1 is greater than 0.1 mm, it will lead to sluggish cutting and affect cutting efficiency. Therefore, the fillet radius is set to a range of 0.03 mm to 0.1 mm, which balances cutting efficiency and safety. Similarly, the second side wall 1222 has the same design dimensions as the first side wall 1221 and has the same effect.

[0103] In this embodiment, the first side-cut wall 1221 and the second side-cut wall 1222 are inclined surfaces extending from the outer wall of the side suction part 12 to the inner wall. The angle between the first side-cut wall 1221 and the inner wall of the side suction part 12 is an acute angle, and the angle between the second side-cut wall 1222 and the inner wall of the side suction part 12 is an acute angle, thereby further improving the shearing efficiency.

[0104] like Figure 19 As shown, in the fourth embodiment of this example, the side suction hole 122 includes a third arc-shaped wall 1225 and a fourth arc-shaped wall 1226 that are arranged opposite to each other and connected in the axial direction, that is, the edges of the two arc-shaped walls are connected. The third arc-shaped wall 1225 and the fourth arc-shaped wall 1226 are configured as a first side cutting wall 1221 on one side in the axial direction and a second side cutting wall 1222 on the other side. This configuration can improve the structural strength of the side suction hole 122 while ensuring that the side suction hole 122 has sufficient size to allow lesions, plaques and thrombi to pass through.

[0105] As an optional implementation, the angle between the third arcuate wall 1225 and the fourth arcuate wall 1226 and the inner wall of the side suction part 12 is an acute angle, thereby improving the shearing efficiency.

[0106] like Figure 19 As shown, as an optional implementation, a plurality of side suction holes 122 are arranged at intervals along the axial direction of the side suction portion 12, for example, three side suction holes 122 are arranged at intervals along the axial direction of the side suction portion 12, thereby improving the efficiency of suctioning and shearing lesion plaques and thrombi.

[0107] like Figure 10 As shown, the present invention provides a rotary cutting and volume reduction device, including the above-mentioned rotary cutting head assembly.

[0108] The rotary cutting head assembly in this embodiment has the same composition, connection relationship and beneficial effects as the rotary cutting head assembly described above, and will not be repeated here.

[0109] like Figure 20 and Figure 21 As shown, in one embodiment, the rotary cutting and volume reduction device includes a limiting structure, which comprises a first limiting surface 201, a second limiting surface 401, and a rolling assembly 5. The first limiting surface 201 is located at the distal end of the outer tube assembly, facing the proximal end of the outer tube assembly. The second limiting surface 401 is located at the distal end of the torque transmission tube 4, at the opposite proximal end of the first limiting surface 201, and facing the first limiting surface 201. The rolling assembly 5 includes a rolling element disposed between the first limiting surface 201 and the second limiting surface 401. The first limiting surface 201 is rotatably connected to the second limiting surface 401 through the rolling element, and the first limiting surface 201 is used to limit the displacement of the rolling element and the second limiting surface 401 towards the distal end.

[0110] When the rotary cutting head rotates, the first limiting surface 201 and the second limiting surface 401 can restrict the distal end of the torque transmission tube 4 from moving axially, thereby limiting the rotary cutting head from moving to the distal end and improving the axial stability of the rotary cutting head. The rolling component 5 can convert planar friction into rolling friction. Multiple rolling elements as friction pairs can reduce the friction between the first limiting surface 201 and the second limiting surface 401, thereby reducing energy loss and ensuring the cutting efficiency of the rotary cutting head. Therefore, the limiting structure provided by the present invention can not only improve the axial stability of the rotary cutting head, improve safety, prevent the cutting head from breaking, and ensure the service life of the cutting head, but also further ensure the cutting efficiency of the rotary cutting head. In addition, reducing the friction between the first limiting surface 201 and the second limiting surface 401 is also conducive to reducing heat accumulation and further improving the service life of the cutting head.

[0111] like Figure 21 and Figure 24As shown, in this embodiment, the rolling element is a ball. Multiple balls can serve as the rolling elements of a planar bearing, transforming the planar friction where the first limiting surface 201 and the second limiting surface 401 are in direct contact into rolling friction between the plane and the ball, thereby reducing the frictional force.

[0112] In this embodiment, the ball bearing is made of a high-rigidity inorganic non-metallic material, metallic material, or polymeric material. For example, the ball bearing can be made of zirconium oxide, cobalt-chromium alloy, silicon nitride, stainless steel, or polyetheretherketone (PEEK). All of these materials have good biocompatibility. Zirconium oxide and silicon nitride are inorganic non-metallic materials, and when made into zirconium oxide ceramic beads or silicon nitride ceramic beads, they exhibit high hardness. Cobalt-chromium alloy and stainless steel are metallic materials, and when made into cobalt-chromium alloy beads or stainless steel beads, they exhibit high hardness. PEEK is a polymeric material, characterized by high hardness and compressive strength. The ball bearing made from these materials can further counteract the forward force of the torque transmission tube 4. Of course, in addition to the materials mentioned above, other materials with high rigidity and biocompatibility can also be used, which will not be listed here.

[0113] like Figure 21 As shown, a limiting ring 24 is provided on the inner wall of the port at the far end of the outer tube assembly. A first limiting surface 201 is located on the limiting ring 24. A protruding structure 43 is provided at the far end of the torque transmission tube 4. The protruding structure 43 includes a protruding part 431 and an annular flange 432 provided on the side wall of the protruding part 431. The protruding part 431 passes through the limiting ring 24 and is connected to the rotary cutting head. The annular flange 432 and the limiting ring 24 correspond in the axial direction. A second limiting surface 401 is located on the annular flange 432. The limiting ring 24 and the annular flange 432 can play an axial limiting role, and the protruding part 431 can improve the connection strength between the double-layer metal spring tube 41 and the rotary cutting head.

[0114] like Figure 20 and Figure 22 As shown, in this embodiment, the rotary cutting and volume reduction device includes a driving device, and the torque transmission tube 4 includes a double-layer metal spring tube 41 and a coiled spring 42. The coiled spring 42 is sleeved on the outer wall of the double-layer metal spring tube 41, and the ends of the double-layer metal spring tube 41 and the coiled spring 42 are fused to form the protruding structure 43. The driving device can drive the torque transmission tube 4 to rotate. During the rotation, the coiled spring 42 can not only transmit torque to drive the rotary cutting head to rotate, but also form a spiral negative pressure in the guide tube 3. The spiral negative pressure can provide an attractive force to the inner cutting hole 21 and the side suction hole 122. The protruding structure 43 is formed by melting and polishing the ends of the double-layer metal spring tube 41 and the coiled spring 42, thereby improving the connection strength between the torque transmission tube 4 and the rotary cutting head and the torque transmission effect.

[0115] like Figure 22 and Figure 23As shown, in one embodiment, the double-layer metal spring tube 41 includes a first metal wire 411 and a second metal wire 412, the first metal wire 411 and the second metal wire 412 are wound in opposite directions, and the diameter of the spring 42 is greater than the diameter of the first metal wire 411 and the diameter of the second metal wire 412. In specific implementation, the winding direction of the first metal wire 411 is the same as the rotation direction of the rotary cutting head, which can be clockwise. The winding direction of the second metal wire 412 is opposite to the winding direction of the first metal wire 411, which can be counterclockwise. The winding direction of the spring 42 is the same as the winding direction of the first metal wire 411, which can be clockwise. The winding direction of the first metal wire 411 is consistent with the rotation direction of the cutting head, which can ensure that the torque is effectively transmitted to the rotary cutting head and reduce energy consumption. The winding direction of the second metal wire 412 can prevent the first metal wire 411 from unwinding, thereby improving the structural strength of the double-layer metal spring tube 41 and ensuring the effectiveness of the torque transmission tube 4. The spring 42 can effectively provide suction negative pressure.

[0116] In one specific embodiment, the diameter of the first metal wire 411 can be in the range of 0.1mm to 0.3mm, the diameter of the second metal wire 412 can be in the range of 0.1mm to 0.3mm, the outer diameter of the first metal wire 411 and the second metal wire 412 after winding and forming is 1.45mm, and the diameter of the spring 42 can be set to be in the range of 0.2mm to 0.6mm.

[0117] In one specific embodiment, the inner layer of the double-layer metal spring tube 41 can be formed by one or more first metal wires 411, and the outer layer of the double-layer metal spring tube 41 can be formed by one or more second metal wires 412.

[0118] In a preferred embodiment, the inner layer of the double-layer metal spring tube 41 is formed by winding multiple first metal wires 411, with the pitch of two adjacent first metal wires 411 being the diameter of the first metal wire 411, meaning that two adjacent first metal wires 411 are closely fitted together. The outer layer of the double-layer metal spring tube 41 is formed by winding multiple second metal wires 412, with the pitch of two adjacent second metal wires 412 being the diameter of the second metal wire 412, meaning that two adjacent second metal wires 412 are closely fitted together. The double-layer metal spring tube 41, formed by winding multiple first metal wires 411 and multiple second metal wires 412, can further avoid unwinding, thereby ensuring the effectiveness of the torque transmission tube 4.

[0119] For example, the inner layer of the double-layer metal spring tube 41 is made of 12 first metal wires 411, with the pitch of any one of the first metal wires 411 being 1mm to 3mm. The outer layer of the double-layer metal spring tube 41 is made of 12 second metal wires 412, with the pitch of any one of the second metal wires 412 being 1mm to 3mm. The pitch of the spring 42 can be 1mm to 2.8mm.

[0120] As an optional implementation, the inner layer of the double-layer metal spring tube 41 is formed by winding a first metal wire 411, the pitch of which is equal to the diameter of the first metal wire 411. The outer layer of the double-layer metal spring tube 41 is formed by winding a second metal wire 412, the pitch of which is equal to the diameter of the second metal wire 412. This reduces manufacturing difficulty.

[0121] like Figure 20 , Figure 22 and Figure 24 As shown, in this embodiment, the outer tube assembly includes an inner blade 2 and a catheter 3. The inner blade 2 is embedded in the distal end of the catheter 3. The proximal end of the rotary cutting blade has an inner cavity 121, and the inner blade 2 is coaxially disposed in the inner cavity 121. The side wall of the proximal end of the rotary cutting blade has a side suction hole 122. The inner blade 2 has an inner incision hole 21 corresponding to the side suction hole 122. The distal end of the inner blade 2 has an opening, and the inner wall of the opening has a limiting ring 24. The side suction hole 122 of the rotary cutting blade and the inner incision hole 21 of the inner blade 2 can be used to suction the excised lesion plaque and thrombus. When the side suction hole 122 and the inner blade 2 move relative to each other, the relative movement of the inner wall of the side suction hole 122 and the inner wall of the inner blade 2 has a shearing effect, which can further cut and subdivide the lesion plaque and thrombus, improve the suction efficiency of the lesion plaque and thrombus, and at the same time avoid the lesion plaque and thrombus from blocking the catheter 3.

[0122] like Figure 22 and Figure 25 As shown, in this embodiment, the catheter 3 includes an inner layer 31, a reinforcing layer 32, and an outer layer 33 arranged from the inside to the outside. The proximal end of the inner blade 2 is embedded and connected between the inner layer 31 and the outer layer 33 and is in contact with the reinforcing layer 32. Placing the reinforcing layer 32 between the inner layer 31 and the outer layer 33 can improve the structural strength of the catheter 3. Embedding and connecting the proximal end of the inner blade 2 between the inner layer 31 and the outer layer 33 can connect the proximal end of the inner blade 2 and the catheter 3 as a whole, thereby improving the stability of the connection between the inner blade 2 and the catheter 3.

[0123] In this embodiment, the inner layer 31 and the outer layer 33 are made of polymer material, and the reinforcing layer 32 is a braided layer. The inner layer 31 and the outer layer 33 made of polymer material can improve lubrication and the smoothness of the propulsion conduit 3, while the braided layer can improve structural strength. For example, the polymer material can be polyurethane or other commonly used conduit 3 materials, and the braided layer can be formed by braiding metal wires.

[0124] Considering the high stress at the connection between the inner cutter head 2 and the conduit 3, which poses a risk of deformation or detachment, in this embodiment, the proximal end of the inner cutter head 2 is provided with an embedding section 22. The wall thickness of the embedding section 22 is the same as the thickness of the reinforcing layer 32. This arrangement ensures that the outer wall dimensions of the conduit 3 remain consistent, guaranteeing smooth movement of the conduit 3. The distal outer wall of the embedding section 22 is provided with a protruding ring 23. The proximal end of the protruding ring 23 connects to the distal end of the conduit 3, and the distal end of the protruding ring 23 rotatably engages with the proximal end of the rotary cutting head. The outer diameter of the protruding ring 23 is the same as the outer diameter of the outer layer 33. This arrangement further improves the reliability of the connection between the inner cutter head 2 and the conduit 3, ensures that the outer diameter of the conduit 3 remains consistent during the connection between the inner cutter head 2 and the conduit 3, and prevents obstruction of the rotation of the rotary cutting head.

[0125] like Figure 12 , Figure 22 and Figure 25 As shown, in this embodiment, the outer wall of the embedded section 22 is provided with multiple through holes 221. These through holes 221 allow partial infiltration of the outer layer 33. That is, during the fabrication of the conduit 3, some material of the outer layer 33 is incorporated into the through holes 221, forming an embedded tenon-and-mortise structure between the outer layer 33 and the embedded section 22, further improving the reliability of the connection between the inner blade 2 and the conduit 3. Furthermore, the total amount of polymer infiltrated into the through holes 221 during rheological changes should be consistent with the polymer infiltrated into adjacent braided layers of the same length to ensure the uniformity of the outer layer.

[0126] To achieve material volume fraction matching between the embedded section 22 and the braided layer of the conduit 3, the through-hole 221 of the embedded section 22 is designed as an oblong hole, and multiple through-holes 221 are arranged in an array on the outer wall of the embedded section 22. The circumferential dimension of the through-hole 221 is defined as the length. The axial dimension of the through hole 221 is defined as the width. By combining the PPI of the braided layer and the braiding angle, the total open area ratio of the through-hole 221 is controlled. This makes its volume fraction with the braided layer metal wires Satisfying the approximation relation, that is, guaranteeing This creates a volume compensation zone with a void ratio consistent with the braided layer during the thermal rheological forming process. This design effectively reduces the interfacial stress concentration between the guide tip and the cutter head metal substrate, improving bond strength and rheological stability.

[0127] Please refer to Table 2 for details.

[0128] Table 2: Symbols and their meanings

[0129]

[0130] The volume fraction of the braided layer wires can be calculated using the following formula:

[0131]

[0132] The open area ratio of a through hole can be calculated using the following formula:

[0133]

[0134] The fill rate matching design criterion is:

[0135]

[0136] The porosity of the through-hole 221 should be matched with the volume fraction of the braided layer not occupied by the metal wires in order to provide an equivalent material flow space during thermorheological processes.

[0137] Although embodiments of the invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the invention, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A rotary cutting head, characterized in that, include: The cutter head body (1) is provided with a plurality of rotary cutting portions (11) extending from the proximal end to the distal end. The plurality of rotary cutting portions (11) are arranged at intervals along the circumference of the cutter head body (1). A cutting groove (115) is provided between two adjacent rotary cutting portions (11). The rotary cutting portion (11) includes a cutting blade (111). In the rotation direction of the rotary cutting portion (11), the rotary cutting portion (11) includes a front cutting surface (112) provided on the front side of the cutting blade (111) and a rear cutting surface (113) provided on the rear side of the cutting blade (111). The rotary cutting section includes a depth limiting groove (114) located on the front side of the cutting blade (111). The depth limiting groove (114) includes a first inner side and a second inner side connected to each other and forming an angle. The first inner side is connected to the cutting blade (111) and serves as the front cutting face (112). The second inner side is connected to the cutting groove (115). The distance between the connection point of the first inner side and the second inner side and the cutting blade (111) is the depth of the depth limiting groove (114). The depth of the depth limiting groove (114) is used to limit the ultimate cutting depth. The ultimate cutting depth refers to the depth limiting groove (114) gradually filled by the removed lesion plaque during the cutting process of the cutting blade (111) rotating one revolution, so as to prevent the cutting blade (111) from continuing to cut the unremoved lesion plaque or the inner wall of the blood vessel.

2. The rotary cutting head according to claim 1, characterized in that, The cutting groove (115) includes a first groove surface (1151) near the front cutting face (112) and a second groove surface (1152) near the rear cutting face (113), and the second inner side surface of the depth limiting groove (114) serves as a transition surface (1153) connected to the first groove surface (1151).

3. The rotary cutting head according to claim 1, characterized in that, The depth range of the depth limiting groove (114) is 0.05 mm to 0.1 mm.

4. The rotary cutting head according to any one of claims 1 to 3, characterized in that, The cutting blade (111) has a front angle and a rear angle, the front angle having an angle range of 10° to 15° and the rear angle having an angle range of 7° to 12°.

5. The rotary cutting head according to claim 4, characterized in that, The cutting edge (111) has an inclination angle ranging from 20° to 25°.

6. The rotary cutting head according to claim 1, characterized in that, The cutter head body (1) is provided with a side suction part (12), which is located on one side of the proximal end of the rotary cutting part (11). The outer peripheral wall of the side suction part (12) is provided with a plurality of side suction holes (122), and there is a gap between the side suction holes (122) and the proximal end of the rotary cutting part (11).

7. The rotary cutting head according to claim 6, characterized in that, The outer diameter of the side suction part (12) is D1, the maximum outer diameter of the rotary cutting part (11) is D2, and the ratio of D2 to D1 is between 1.05 and 1.

1.

8. A rotary cutting head assembly, characterized in that, The rotary cutting head according to any one of claims 1 to 7 further includes an inner cutting head (2), wherein the cutting head body (1) is provided with an inner cavity (121), and the inner cutting head (2) is coaxially disposed in the inner cavity (121).

9. The rotary cutting head assembly according to claim 8, characterized in that, The inner cutter head (2) is provided with an inner cutting hole (21) corresponding to the side suction hole (122).

10. A rotary cutting and volume reduction device, characterized in that, The rotary cutting head assembly includes any one of claims 8 to 9.

Images