Intravascular stent and developing structure manufacturing method thereof

Abstract

The invention discloses an intravascular stent and a developing structure manufacturing method thereof. The method comprises the following steps: pressing and riveting a developing part into a mounting hole of a developing ring of the intravascular stent; and welding at the seam of the developing ring and the developing part. According to the manufacturing method of the intravascular stent developing structure, the developing part can be quickly, accurately and fixedly installed in the intravascular stent developing ring in a press riveting and welding combined mode, high bonding strength can be achieved between the developing part and the developing ring, and the firmness of the developing part is guaranteed.

Description

Technical Field

[0001] The present application relates to the technical field of medical device manufacturing, and in particular to a method for manufacturing a vascular stent and a developing structure thereof. Background Art

[0002] Vascular stents are placed in the diseased section on the basis of luminal balloon dilatation to support the narrowed and occluded blood vessels, reduce the elastic retraction and reshaping of the blood vessels, and maintain smooth blood flow in the lumen. Vascular stents generally include a support body and a developing ring, wherein: the support body is a hollow tubular structure for supporting blood vessels; the developing ring is fixedly connected to the support body, and the developing ring is filled with a developing component, which is mainly used as an X-ray developing mark in the distal working area.

[0003] In the prior art, since the developing ring and the developing piece are very small parts, the assembly operation is very inconvenient and the assembly accuracy is difficult to control properly. Most of the vascular stent products on the market use a single stamping connection method to press the developing piece into the developing ring, but the connection strength of this method is not enough, and the developing piece is easy to fall off from the developing ring. If it falls off after being placed in the blood vessel, it will not only lose the function of the developing positioning stent position, but also bring safety risks.

[0004] Therefore, how to quickly, accurately and firmly install the developing component into the developing ring of the vascular stent is a technical problem that needs to be solved urgently by those skilled in the art. Summary of the invention

[0005] In view of this, the present application provides a vascular stent and a method for manufacturing a developing structure thereof, which can quickly, accurately and firmly install a developing component into a developing ring of the vascular stent.

[0006] In order to achieve the above application objectives, the present application provides the following technical solutions for the development structure manufacturing method:

[0007] Step S1: Pressing the developing member into the mounting hole of the developing ring of the vascular stent;

[0008] Step S2: welding is performed at the joint between the developing ring and the developing member to form a developing structure of the blood vessel stent.

[0009] Optionally, in step S1, after the developing member is pressed into the mounting hole, the developing member is deformed from a spherical or cylindrical shape before pressing to a shape after pressing in which at least a portion of the developing member is in close contact with the inner wall of the mounting hole, and an annular gap is formed between the top of the inner wall of the mounting hole and the developing member;

[0010] In step S2, when welding is performed at the joint between the developing ring and the developing member: the weld is located in the annular gap and does not protrude from the top of the developing ring; or, the weld completely covers the annular gap, and the inner and outer edges of the weld are respectively located radially inward and radially outward of the annular gap.

[0011] Optionally, in step S1, when the developing member is pressed into the mounting hole, a punching head provides a punching force for the developing member, wherein:

[0012] The bottom end of the punch head is provided with an annular protrusion capable of limiting the developing member at the joint between the developing ring and the developing member to form an annular gap. When the punch head applies pressure to the developing ring, the outer contour of the annular protrusion can be embedded in the top position of the wall of the mounting hole, and the pressure is stopped when the developing member is flush with the developing ring.

[0013] Alternatively, the bottom end of the punch head is a spherical bottom end capable of forming a concave spherical groove at the top end of the developer; the concave spherical groove is located in the mounting hole, and the projection of the spherical bottom end in the vertical direction covers the mounting hole;

[0014] Alternatively, the bottom end of the punch head is a planar bottom end; the end surface of the developing ring facing the punch head is formed into a plane or the end surface of the developing ring facing the punch head is provided with a groove capable of accommodating the planar bottom end, and the mounting hole is located at the bottom surface of the groove.

[0015] Optionally, in step S2, when welding is performed at the joint between the developing ring and the developing member:

[0016] A first annular weld is provided in the first annular welding area; the outer side and the inner side of the first annular weld are respectively the first outer side and the first inner side;

[0017] A second annular weld is provided in the second annular welding area; the outer side and the inner side of the second annular weld are respectively the second outer side and the second inner side;

[0018] The radial dimensions of the first outer side, the second outer side, the first inner side, and the second inner side are sequentially reduced so that the annular overlapping area of ​​the first annular weld and the second annular weld covers the annular gap.

[0019] Optionally, when the first annular weld is provided in the first annular welding area, the welding route thereof is a first spiral curve, and the spiral center of the first spiral curve moves circumferentially along the center ring of the first annular welding area;

[0020] and / or,

[0021] When the second annular weld is arranged in the second annular welding area, the welding route thereof is a second spiral curve, and the spiral center of the second spiral curve moves circumferentially along the center ring of the second annular welding area.

[0022] Optionally, in step S1:

[0023] Before the developing member is pressed into the mounting hole: the developing member is a spherical or cylindrical structure, the mounting hole is a through hole structure whose inlet end cross section is the same as or larger than the outlet end cross section, and the cross section of the through hole structure is circular; or the developing member is an ellipsoid or ellipsoidal structure, the mounting hole is a through hole structure whose inlet end cross section is the same as or larger than the outlet end cross section, and the cross section of the through hole structure is elliptical;

[0024] After the developing component is pressed into the mounting hole, the developing component is nested in the mounting hole and interference fits with the mounting hole, and the developing component is in a columnar structure adapted to the mounting hole.

[0025] Optionally, in step S2, the welding depth corresponding to the annular gap is 1 / 4 to 3 / 4 of the height of the mounting hole.

[0026] Optionally, in step S1, when the developing member is pressed into the mounting hole, a punching head moving from top to bottom provides a punching force for the developing member, a cylinder provides power for the punching head, and before the punching starts, the air pressure is set to any value in the range of 1.4 MPa to 1.8 MPa, and the punching time is adjusted to any value in the range of 2.5S to 3.5S;

[0027] In step S2, when welding is performed at the joint between the developing ring and the developing member: the welding point diameter parameter is any value in the range of 0.3 mm to 0.7 mm, the welding speed parameter is any value in the range of 6 Hz to 10 Hz, the welding power is any value in the range of 230 to 270 V, and the welding depth is any value in the range of 1.5 to 3.5 ms.

[0028] Optionally, in step S2, the following preparation steps are included before welding is performed at the joint between the developing ring and the developing member:

[0029] Step S021: Sleeve and fix the collar on the welding shaft, wherein a positioning groove is provided on the side of the collar;

[0030] Step S022: sleeve the sleeve on the welding shaft, the side of the sleeve is provided with a positioning protrusion, and the positioning protrusion is located in the positioning groove to correspond to the position of the developing ring to be welded;

[0031] Step S023: After adjusting and confirming the welding parameters and welding position of the welding equipment on the sleeve, the sleeve is removed, and the developing ring to be welded is placed in the positioning groove of the sleeve ring for limiting.

[0032] Optionally, in step S023:

[0033] Adjusting the welding parameters includes adjusting the focal length so that the laser hits the sleeve;

[0034] And / or, adjusting the welding position includes adjusting a frame line position on a display of the welding device to determine a focus position.

[0035] Optionally, in step S2, when welding the joint between the developing ring and the developing member, the developing material located at or near the annular gap between the developing ring and the developing member is melted into the annular gap by laser.

[0036] Optionally, in step S1, when the developing member is pressed into the mounting hole, the vascular stent is positioned by a stamping tool, wherein:

[0037] The punching tool is provided with a first positioning groove capable of positioning the support body of the vascular stent, and a second positioning groove capable of positioning the developing ring of the vascular stent.

[0038] Optionally, the stamping tool includes a stamping base, the second positioning groove is arranged on the top side of the stamping base, and the side of the stamping base is provided with a plurality of strip grooves for accommodating other developing rings, the other developing rings are developing rings of the vascular stent except the developing ring to be pressed currently, the plurality of strip grooves are located below the second positioning groove and are arranged in sequence along an arc trajectory, and the length direction of each strip groove is located in the radial direction of different positions of the arc trajectory.

[0039] Optionally, the stamping base comprises:

[0040] A base, the second positioning groove is arranged on the side edge of the top surface of the base;

[0041] A gasket is located on the top of the base, wherein a third positioning groove is provided in the area of ​​the gasket above the second positioning groove, and an edge of a projection area of ​​the third positioning groove on the base is located radially outside the second positioning groove;

[0042] The punching head for applying pressure to the developing member and the developing ring comprises:

[0043] A columnar body, wherein a projection area of ​​the columnar body on the gasket covers the third positioning groove;

[0044] The punching end is located at the bottom end of the columnar body and is aligned with the second positioning groove in the vertical direction. Moreover, the projection area of ​​the punching end on the gasket is located in the third positioning groove.

[0045] Optionally, in the above method, the stamping tool further comprises:

[0046] A punch head mounting frame is located above the pressing base and is fixedly connected thereto; the punch head mounting frame is provided with a vertical through hole;

[0047] A punch head is relatively movably mounted in the vertical through hole of the punch head mounting frame and is used for riveting the developing member and the developing ring;

[0048] A cylinder, whose driving shaft is located above the punching head and can be lifted to a preset height position, and the bottom end of the driving shaft located at the preset height position has a preset height distance greater than zero from the punching head; and the driving shaft can press the punching head to a punching position to press and rivet the developing member into the mounting hole;

[0049] An elastic member is arranged between the punching head and the punching head mounting frame, and is used for lifting the punching head from the punching position to an initial position.

[0050] The present application also provides a vascular stent, wherein the developing structure of the vascular stent is manufactured by the method as described above, and the developing structure is flush with the developing ring in the axial direction of the vascular stent.

[0051] Optionally, the developing structure comprises a riveting portion and a welding portion, the riveting portion is located in the mounting hole of the vascular stent, the welding portion is arranged around the riveting portion, and the developing structure is fixed to the mounting hole through the riveting portion and the welding portion.

[0052] The beneficial effects of the present application are as follows: the present application provides a method for manufacturing a vascular stent developing structure, which adopts a combination of riveting and welding to quickly and accurately fix the developing component in the vascular stent developing ring, and can make the developing component and the developing ring have a high bonding strength, thereby ensuring the firmness of the vascular stent developing component. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0054] Figure 1A schematic diagram of the structure of a vascular stent provided in an embodiment of the present application.

[0055] Figure 2 A flow chart of a method for manufacturing a vascular stent development structure provided in an embodiment of the present application;

[0056] Figures 3 to 5 Schematic cross-sectional view of three different structures of stamping heads and their corresponding developing parts provided in the embodiments of the present application.

[0057] Figure 6 An axonometric view of a stamping tool provided in an embodiment of the present application.

[0058] Figure 7 for Figure 6 A magnified view of the local structure.

[0059] Figure 8 A schematic diagram of the operation of moving the vascular stent developing ring to the second positioning groove of the stamping base provided in an embodiment of the present application.

[0060] Fig. 9 A schematic diagram of the combined structure of the developing member and the developing ring provided in an embodiment of the present application.

[0061] Fig.10 A schematic diagram of a welding route provided in an embodiment of the present application.

[0062] Fig.11 Schematic diagram of the weld structure on the developing member and the developing ring provided in an embodiment of the present application.

[0063] Fig.12 A schematic diagram of the combined structure of a welding shaft, a welding ring, and a welding sleeve provided in an embodiment of the present application.

[0064] in:

[0065] 1-development parts, 2-vascular stents, 3-stamping tools,

[0066] 21-developing ring, 22-support body, 210-mounting hole,

[0067] 31-stamping base, 32-stamping head, 33-stamping head mounting seat,

[0068] 34-component, 35-cylinder, 36-adjustment mechanism,

[0069] 41-welded shaft, 42-ring, 43-sleeve,

[0070] 301-first positioning groove, 302-second positioning groove,

[0071] 303-strip groove, 304-third positioning groove,

[0072] 311-base, 312-gasket, 321-stamping end, 322-columnar body,

[0073] 3211-annular protrusion, 3213-flat bottom,

[0074] 3212-spherical bottom, 11-concave spherical groove,

[0075] 211-interference fit contact surface, 212-annular gap, 213-groove,

[0076] 100-weld,

[0077] 101-first annular welding area, 102-second annular welding area, 103-annular overlapping area,

[0078] 1011 - outer side of the first welding area, 1012 - inner side of the first welding area,

[0079] 1021 - outer side of the second welding area, 1022 - inner side of the second welding area,

[0080] a- Schematic diagram of the direction of the first welding route,

[0081] b- Schematic diagram of the direction of the second welding route. DETAILED DESCRIPTION

[0082] The present application provides a method for manufacturing a vascular stent and its developing structure, which uses a combination of riveting and welding to quickly and accurately fix a developing component in a developing ring of the vascular stent, and can also provide a high bonding strength between the developing component and the developing ring, thereby ensuring the firmness of the developing component.

[0083] It should be noted here that the vascular stent provided in the present application can be a peripheral artery stent or other types of vascular stents, such as a lower limb artery stent or an aortic stent or a renal artery stent, etc. The present application does not specifically limit the specific type of vascular stent.

[0084] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0085] See also Figure 1The vascular stent 2 provided in the embodiment of the present application includes a support body 22 for supporting a blood vessel, and a developing ring 21 located at the end of the support body 22, and the developing ring 21 is provided with a mounting hole 210 for mounting the developing member 1.

[0086] See also Figure 2 The manufacturing method of the vascular stent developing structure provided in the embodiment of the present application includes steps S1 and S2, wherein: step S1, riveting the developing member 1 into the mounting hole 210 of the developing ring 21 of the vascular stent 2, at which time, the developing member 1 and the developing ring 21 are interference fit; step S2, welding is performed at the joint between the developing ring 21 and the developing member 1. The vascular stent manufactured by the manufacturing method can make the developing member 1 and the developing ring 21 have a high bonding strength.

[0087] Further, in some embodiments, the above step S1 includes: after the developing member 1 is riveted into the mounting hole 210 of the developing ring 21 of the vascular stent 2, the developing member is deformed from a spherical or cylindrical shape before the pressing to a shape after the pressing in which at least a part of the developing member is in close contact with the inner wall of the mounting hole, and an annular gap 212 is formed between the top side edge of the inner wall of the mounting hole 210 and the developing member 1 (see Figure 3 ), that is, during the stamping stage, an annular gap 212 capable of being filled with solder is reserved on the circumference of the developing member 1. Thus, in the above step S2, when welding is performed at the joint between the developing ring 21 and the developing member 1, the solder (e.g., nickel-titanium material) is first filled in the annular gap 212 on the circumference of the developing member 1, and then it is welded, or the edge area of ​​the developing member 1 is directly welded without superimposing the solder, and after the welding is completed, the annular gap 212 can be filled or a smaller annular gap 212 is left, and the ideal state is that the developing member 1 at the weld 100 is just located in the above annular gap 212 and does not protrude from the top of the developing ring 21 to ensure the safety of the blood vessel wall. Alternatively, the weld 100 completely covers the annular gap 212, and the inner side and outer side of the weld 100 are respectively located radially inside and radially outside the annular gap 212.

[0088] It should be noted here that the top of the developing ring 21 mentioned in the present application refers to the annular end surface on one side of the developing ring 21 located at the top when it is in the riveting process and the welding process. It is also the side close to the punch head during the riveting process, and also the side close to the welding machine during the welding process.

[0089] In some embodiments, the above step S1 includes: when the developing member 1 is riveted into the mounting hole 210 of the developing ring 21 of the vascular stent 2, a punching head 32 that can reciprocate up and down in the vertical direction is used to provide a punching force for the developing member 1, and an annular protrusion 3211 is provided at the bottom of the punching head 32, and the annular protrusion 3211 can limit the developing member at the joint of the developing ring 21 and the developing member 1 to form an annular gap 212, and when the punching head 32 applies pressure to the developing ring, the outer contour of the annular protrusion 3211 can be embedded in the top position of the hole wall of the mounting hole 210, and when the developing member is flush with the developing ring Stop applying pressure. The annular protrusion can not only limit the developing component 1 during the riveting process to prevent the developing material from overflowing from the developing ring, but also form an annular gap 212 with a concave structure at the joint between the developing ring 21 and the developing component 1 (specifically, the joint between the top periphery of the riveted developing component 21 and the developing mounting hole 210). The annular gap 212 not only provides a groove for accommodating solder / weld in the subsequent welding process, facilitating the placement and filling of solder, but also enables the top of the weld, the developing component 1 and the developing ring 21 to form a flat top surface to avoid protrusions after welding.

[0090] In other embodiments, the bottom end of the punch head 32 is formed with a spherical bottom end 3212 that enables the top end of the developing member 1 to be a concave spherical groove 11; the concave spherical groove 11 is located in the mounting hole 210, and the projection of the spherical bottom end 3212 in the vertical direction covers the mounting hole 210.

[0091] In other embodiments, the bottom end of the punch head 32 is a planar bottom end 3213; the end surface of the developing ring 21 facing the punch head 32 is formed as a plane or the end surface of the developing ring 21 facing the punch head 32 is provided with a groove 213 capable of accommodating the planar bottom end 3213, and the mounting hole 210 is located on the bottom surface of the groove 213.

[0092] In some embodiments, the developing member 1 is preferably spherical or ellipsoidal, and correspondingly, the mounting hole 210 of the developing ring 21 is a circular hole or an elliptical hole close to a circular hole, which is conducive to ensuring that the developing member 1 can be uniformly filled in the mounting hole 210 during the stamping process. However, it is not limited to this. In other embodiments, developing members 1 of other shapes can also be used, as long as they can be filled and fixed in the mounting hole 210 of the developing ring 21 by riveting and welding. In specific implementation, if the developing member 1 is spherical, it can be convenient to form the above-mentioned annular gap 212 after it is stamped into the mounting hole 210 of the developing ring 21.

[0093] The annular gap 212 can also provide a circulation space for the solder (developing part) when the welding is melted, so that the solder can fully fill the gap between the unmelted developing part 1 and the mounting hole 210, thereby strengthening the connection strength between the developing part 1 and the developing ring 21. At the same time, the edge of the developing part 1 after welding will not protrude from the developing ring 21, making the surface of the developing ring 21 and the developing part 1 smooth, avoiding scratches on the blood vessel wall.

[0094] See also Figure 3 In some embodiments, the above step S1 includes:

[0095] Before the developing member 1 is riveted into the mounting hole 210 of the developing ring 21 of the vascular stent 2, the developing member 1 is a spherical structure, and the mounting hole 210 is a through-hole structure with a larger inlet end section than the outlet end section, and the cross-sectional shape of the through-hole structure is circular, that is, the developing ring 21 is a circular ring, which can help ensure the uniformity of filling during the stamping process; or, before the developing member 1 is riveted into the mounting hole 210 of the developing ring 21 of the vascular stent 2, the developing member 1 is an ellipsoidal structure, and the mounting hole 210 is a through-hole structure with a larger inlet end section than the outlet end section, and the cross-sectional shape of the through-hole structure is an ellipse;

[0096] After the developing member 1 is riveted into the mounting hole 210 of the developing ring 21 of the vascular stent 2, the developing member 1 is nested in the mounting hole 210 and has an interference fit therewith, and the developing member 1 is a frustum-shaped column structure adapted to the mounting hole 210. For details, see Figure 3 .

[0097] For example, in some embodiments, the developing member 1 before riveting is a tantalum ball with a diameter of about 0.37 mm and a volume of about 0.026 mm. 3 The diameter of the developing ring 21 is about 0.44mm, and the hollow volume of the mounting hole 210 is about 0.0185mm 3 After the developing member 1 is riveted into the mounting hole 210 of the developing ring 21, the developing member 1 is deformed into a frustum-shaped columnar structure that is interference-fitted with the mounting hole 210, such as Figure 3 as shown in .

[0098] It should be noted that the spherical developing member 1 is easier to load into the mounting hole 210 of the developing ring 21 than the truncated cone developing member 1. Moreover, the spherical developing member 1 and the annular developing ring 21 can form an interference fit after riveting, and no excess material overflows.

[0099] See also Figure 6In some embodiments, the above step S1 includes: when the developing member 1 is riveted into the mounting hole 210 of the developing ring 21 of the vascular stent 2, a punching head 32 moving from top to bottom provides a punching force for the developing member 1, and a cylinder 35 provides power for the punching head 32. Before the punching starts, the air pressure can be set to 1.4MPa to 1.8MPa, and the punching time can be adjusted to 2.5S to 3.5S. For example, the air pressure is set to 1.6MPa, and the punching time is adjusted to 3S.

[0100] In some embodiments, the depth of welding corresponding to the annular gap 212 in step S2 is 1 / 4 to 3 / 4 of the height of the mounting hole 210. The above step S2 includes: when welding at the joint of the developing ring 21 and the developing member 1, preferably setting the welding point diameter parameter to 0.5 mm, the welding speed parameter to 8 Hz, the welding power range to 230 to 270 V, and the welding depth range to 1.5 to 3.5 ms. While ensuring a good welding effect, the connection will not be perforated or broken due to excessive welding.

[0101] In some embodiments, when the developing member 1 is riveted into the mounting hole 210 of the developing ring 21 of the vascular stent 2, the vascular stent 2 is positioned by the punching tool 3. Figure 6 and Figure 7 The stamping tool 3 is provided with a first positioning groove 301 capable of positioning the support body 22 of the vascular stent 2, and a second positioning groove 302 capable of positioning the developing ring 21 of the vascular stent 2. The stamping tool 3 includes a stamping base 31, and the second positioning groove 302 is arranged on the top side of the stamping base 31; the side of the stamping base 31 is also provided with a plurality of strip grooves 303 for accommodating other developing rings (i.e., other developing rings except the developing ring 21 to be riveted at present), and the plurality of strip grooves 303 are all located below the second positioning groove 302 and arranged in sequence along the arc track C, and the length direction L of each strip groove 303 is respectively located in the radial direction of different positions of the arc track C, so that other developing rings of the vascular stent 2 can be easily accommodated, and the developing ring 21 with riveting is conveniently positioned in the second positioning groove 302.

[0102] In step S2, when welding is performed at the joint between the developing ring 21 and the developing member 1:

[0103] A first annular weld 101 is provided in the first annular welding area; the outer side and the inner side of the first annular weld 101 are respectively a first outer side 1011 and a first inner side 1012;

[0104] A second annular weld 102 is provided in the second annular welding area; the outer side and the inner side of the second annular weld 102 are respectively a second outer side 1021 and a second inner side 1022;

[0105] The radial dimensions of the first outer side 1011 , the second outer side 1021 , the first inner side 1012 , and the second inner side 1022 decrease sequentially, so that the annular overlap area 103 of the first annular weld 101 and the second annular weld 102 covers the annular gap 212 .

[0106] The diameter of the first outer side 1011 of the first annular welding area is larger than the diameter of the second outer side of the second annular welding area; the diameter of the first inner side of the first annular welding area is larger than the diameter of the second inner side of the second annular welding area, and smaller than the diameter of the second outer side.

[0107] Further, when the first annular weld 101 is arranged in the first annular welding area, its welding route is the first spiral curve a, and the spiral center of the first spiral curve a moves circumferentially along the center ring of the first annular welding area. The center ring refers to an annular track located at the center position between the outer side and the inner side of the first annular welding area, and is also located at the center position between the first outer side 1011 and the first inner side 1012 of the first annular weld 101.

[0108] When the second annular weld 102 is arranged in the second annular welding area, the welding route is the second spiral curve b, and the spiral center of the second spiral curve b moves circumferentially along the center ring of the second annular welding area. The center ring refers to an annular track located at the center position between the outer side and the inner side of the second annular welding area, and is also located at the center position between the first outer side 1021 and the first inner side 1022 of the second annular weld 102.

[0109] The order of forming the first annular weld and the second annular weld can be adjusted, such as adopting a welding route of first forming the first spiral curve a and then the second spiral curve b, or alternating.

[0110] For further information, see Figure 6 and Figure 7 The stamping tool 3 is also provided with an adjusting mechanism 36, through which the height of the position of the component 34 provided with the first positioning groove 301 can be adjusted, so that before the developing member 1 is riveted into the mounting hole 210 of the developing ring 21, the position of the component 34 and the vascular stent 2 is first raised by the adjusting mechanism 36, so that the developing ring 21 of the vascular stent 2 is higher than the horizontal height of the position of the second positioning groove 302 of the stamping base 31, and then the vascular stent 2 is pushed horizontally along the V-shaped groove so that the developing ring 21 is located just above the second positioning groove 302, and then the position of the component 34 and the vascular stent 2 is lowered by the adjusting mechanism 36, so that the developing ring 21 of the vascular stent 2 is moved into the second positioning groove 302, that is, the optimal riveting position, so that the developing ring 21 is positioned at Figure 7 and Figure 8The developing member 1 is inserted into the second positioning groove 302 shown in the figure, so as to facilitate riveting the developing member 1 into the mounting hole 210 of the developing ring 21 .

[0111] In some embodiments, the first positioning groove 301 is a horizontally extending groove, and its cross-sectional shape can be designed to be V-shaped. However, it is not limited thereto, and in other embodiments, the cross-sectional shape of the first positioning groove 301 can also be set to be a rectangle or a trapezoid or other shapes, as long as the support body 22 of the vascular stent 2 can be stably placed.

[0112] See also Figure 6 and Figure 7 In some embodiments, the stamping base 31 for positioning the developing ring 21 includes a base 311 and a gasket 312. Wherein: a second positioning groove 302 is provided at the side of the top surface of the base 311; the gasket 312 is located at the top of the base 311, and a third positioning groove 304 is provided in the area of ​​the gasket 312 above the second positioning groove 302, and the edge of the projection area of ​​the third positioning groove 304 on the base 311 is located radially outside the second positioning groove 302, that is, the second positioning groove 302 is completely located in the projection area of ​​the third positioning groove 304 on the base 311, and maintains a preset distance greater than zero from the edge of the projection area. Correspondingly, the stamping head 32 for riveting the developing member 1 and the developing ring 21 includes a columnar body 322 and a stamping end head 321. The projection area of ​​the columnar body 322 on the gasket 312 covers the third positioning groove 304; the punching head 321 is located at the bottom end of the columnar body 322, aligned with the second positioning groove 302, and the projection area of ​​the punching head 321 on the gasket 312 is located in the third positioning groove 304. In addition, the thickness of the gasket 312 is less than or equal to the axial length of the punching head 321 (i.e., the height of the punching head 321 protruding relative to the columnar body 322), so that the punching head 321 can press the developing member 1 into the mounting hole 210 of the developing ring 21 located in the second positioning groove 302; and the axial length of the punching head 321 is less than the total depth obtained by adding the thickness of the gasket 312 and the depth of the second positioning groove 302. Therefore, under the premise of ensuring the normal riveting process, when the stroke of the punch head 32 is too large, the gasket 312 can play a certain blocking role on the punch head 32, thereby preventing the punch head 21 from being damaged due to excessive stroke and causing damage to the punch end 321 and the punch base 31.

[0113] In some embodiments, the stamping tool 3 includes a stamping base 31 , a stamping head 32 , a stamping head mounting frame 33 , an elastic member and a cylinder 35 . Among them: the punch head mounting frame 33 is located above the pressing base 31 and is fixedly connected thereto; the punch head mounting frame 33 is provided with a vertical through hole; the punch head 32 can be relatively movably mounted in the vertical through hole of the punch head mounting frame 33, and is used to perform riveting on the developing member 1 and the developing ring 21; the driving shaft of the cylinder 35 is located above the punch head 32, and can be lifted to a preset height position, and the bottom end of the driving shaft at the preset height position has a preset height distance greater than zero with the punch head 32; and the driving shaft of the cylinder 35 can press the punch head 32 to the punching position, so as to rivet the developing member 1 into the mounting hole 210; the elastic member is provided between the punch head 32 and the punch head mounting frame 33, and is used to lift the punch head 32 from the punching position to the initial position; after the punch head 32 is lifted to the initial position under the action of the elastic member, it maintains the above-mentioned preset height distance greater than zero with the bottom end of the cylinder driving shaft until the next punching is performed. In the stamping tool 3, since the cylinder 35 is not directly connected to the stamping head 32, it is not only convenient to overhaul and replace the stamping head 32, but also helps to ensure that the stamping head 32 is accurately aligned with the developing part 1, thereby ensuring a higher riveting effect.

[0114] In a specific embodiment, the riveting process in step S1 of the method for manufacturing the vascular stent developing structure provided by the present application adopts Figure 6 The stamping tool 3 shown is implemented, and its specific operation process includes:

[0115] 1) The cylinder 35 is used to provide power for the punch head 32, and the following settings are made: the air pressure is adjusted to 1.6 MPa; the punching time is adjusted to 3S, and both parameters can be adjusted by the equipment.

[0116] 2) Preparation before stamping:

[0117] Pour the developing element 1 (such as a tantalum ball) into the material box, and put the vascular stent 2 into the first positioning groove 301. The diameter of the developing element 1 is 0.37, and the volume is calculated to be 0.026 mm 3 Each developing ring 21 located at the end of the stent 2 is a circular ring, the diameter of which is 0.44, and the blank volume is 0.0185mm 3 The developing material with a spherical structure is easier to load than the truncated cone structure, and can better ensure the filling uniformity during the stamping process. The developing member 1 and the developing ring 21 form an interference fit after being riveted together, and no excess material overflows.

[0118] 3) Push the vascular stent 2 forward so that all developing rings except the developing ring to be riveted are extended into the strip groove 303 on the side of the stamping base 31; then control the component 34 to lift and lower the vascular stent 2 through the adjustment mechanism 36, so that the outer contour of the developing ring 21 of the vascular stent 2 is flush with the second positioning groove 302 at the top of the stamping base 31; then use tweezers to take a developing part 1 and place it on the developing ring 21 located in the second positioning groove 302 at the top of the pressing base 31.

[0119] 4) Press the pneumatic switch to perform stamping. The cross-sectional structure of the interference fit between the developing member 1 and the developing ring 21 after stamping can be seen in FIG. Figure 3 .

[0120] The welding process in step S2 of the method for manufacturing the vascular stent developing structure provided in the present application specifically includes:

[0121] The equipment for welding the developing member 1 and the developing ring 21 mainly includes a laser spot welding machine and an auxiliary welding machine to implement an automatic welding machine support for the developing member 1 .

[0122] The factors affecting welding parameters mainly include firepower, depth, spot diameter, speed, and waveform. Among them, the waveform is the waveform used for precision welding, the spot diameter affects the size of the weld, and the speed affects the number of welds per unit time. Therefore, the welding spot diameter and speed should meet the weld spot diameter of the design drawing of about 0.1mm, and about 60 welds are welded uniformly in the circumferential direction. Finally, the welding spot diameter parameter is confirmed to be 0.5mm, and the welding speed parameter is 8Hz. In view of the fact that welding firepower and welding depth have a great influence on welding strength and appearance, the welding firepower range is initially set to be 230~270V, and the welding depth range is 1.5~3.5ms. Among them, the firepower intensity depends on the set voltage. The smaller the voltage, the welding cannot be done, and the voltage is too large, causing welding deformation. In addition, the welding depth indicates the cumulative time of welding energy. The longer the time, the greater the welding cumulative energy, the deeper the depth of coverage, and the transition of the developing parts from being unable to weld to welding deformation.

[0123] In summary, in a specific embodiment, the specific operation process of the method for manufacturing a vascular stent developing structure provided in the present application includes:

[0124] 1) Turn on the machine (open the control cabinet door → use the key to turn on the control switch → press the industrial control switch → use the key to turn on the welding machine → turn the knob to turn on the welding machine).

[0125] 2) Set process parameters

[0126] Firepower / V Depth / ms Point diameter / mm Speed / Hz 254±4 2.7±0.2 0.5 8

[0127] 3) Put in the focusing steel sleeve

[0128] See also Fig.12Before welding, the collar 42 must be fixed to the welding shaft 41 by screws, and then the sleeve 43 (usually a steel sleeve) must be put on the welding shaft 41, and the positioning protrusion 431 of the sleeve 43 must be aligned and matched with the positioning groove 421 of the collar 42 to correspond to the position of the sample developing ring. The one positioning groove 421 shown in the figure is only an example. In practice, the corresponding number of positioning grooves 421 should be set according to the number of developing rings. Use welding equipment to confirm the welding parameters on the sleeve 43, adjust the welding position and other parameters, and avoid the laser directly hitting the welding shaft 41 to damage the welding shaft 41. After the welding parameters are debugged, remove the sleeve 43, and then put the sample to be welded into the opening of the collar 42, and then weld.

[0129] 4) Adjust the focus point

[0130] Adjust the magnification to "×5.0" through the zoom button on the lens console on the welding machine, and rotate the focus knob until the image is clear; step on the foot pedal, and the laser hits the shaft sleeve 43. If the focus is not clear, continue to adjust the focus knob.

[0131] 5) Adjust the frame line

[0132] Step 4) and step 5) are that there are several colored frame lines on the welding machine display. The frame line position can be adjusted by the remote control (up, down, left, and right). The role of the frame line is to determine the focus position to ensure that the laser hits the determined position during welding.

[0133] 6) Remove the sleeve 43 and insert the vascular stent 2

[0134] After adjusting the position of the welding point, the shaft sleeve 43 in step 3) is removed, and the developing ring 21 of the blood vessel stent 2 is placed in the positioning groove 421 of the sleeve ring 42 to achieve the limiting of the developing ring 21.

[0135] 7) Set the platform speed and adjust the position of the vascular stent 2 so that it is within the frame line

[0136] The moving parts are the X-axis and Y-axis of the welding machine, and the moving path is set according to the shape of the mounting hole 210 of the developing ring 21 to ensure that the path is consistent with the inner circular ring contour of the developing ring 21 (ie, the top port shape of the mounting hole 210).

[0137] 8) Welding of developing part 1

[0138] The nickel-titanium material around the developing member 1 is melted into the annular gap 212 between the top of the developing member 1 and the inner side edge of the top of the developing ring 21 by laser.

[0139] 9) Inspection

[0140] After the welding between the first developing member 1 and the first developing ring 21 is completed, an appearance inspection is performed, and after passing the inspection, other developing rings 21 and developing members 1 are welded.

[0141] The above method is used to manufacture the developing structure of the vascular stent, and a developing structure that is flush with the surface of the developing ring in the axial direction of the vascular stent is obtained. The developing structure includes a rivet part and a welding part, the rivet part is located in the mounting hole of the vascular stent, the welding part is arranged around the rivet part, and the developing structure is fixed to the mounting hole by the rivet part and the welding part, so as to achieve double connection strength fixation.

[0142] In addition, after the developing member is fixed in the developing ring of the vascular stent by the manufacturing method of the vascular stent developing structure provided by the present application, it can be verified by the ejection force test verification method, and the verification result shows that the method can effectively improve the bonding strength between the developing member and the developing ring. For details, please refer to the table below.

[0143] After the developing ring and the developing part are combined by riveting and welding, the ejection force is tested. The test results are as follows:

[0144] Ejection force test results after riveting and welding (specific example)

[0145]

[0146] After the developer ring and the developer part are combined by riveting only, the ejection force is tested. The test results are as follows:

[0147] Ejection force test results after riveting (comparative example)

[0148]

[0149] From the above test results, it can be seen that the average maximum load of the developing structure of the vascular stent manufactured by the riveting combined with welding method of the present application is about 4 times that of the conventional single riveting method, and the connection strength of the developing part is significantly better than the conventional developing structure. In addition, the method of the present application also ensures that the overall structural morphology of the developing part and the developing ring is good, and the developing structure is formed into a flat surface, which achieves high connection strength without scratching the blood vessel wall.

[0150] Finally, it should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device that includes a series of elements includes not only those elements, but also other elements not explicitly listed.

[0151] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0152] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for manufacturing a vascular stent developing structure, characterized in that: include: Step S1: Pressing the developing member (1) into the mounting hole (210) of the developing ring (21) of the blood vessel stent (2); Step S2: welding is performed at the joint between the developing ring (21) and the developing member (1) to form a developing structure of the blood vessel stent.

2. The method according to claim 1, characterized in that In step S1, after the developing member (1) is pressed into the mounting hole (210), the developing member is deformed from a spherical or cylindrical shape before pressing to a shape after pressing in which at least a portion of the developing member is in close contact with the inner wall of the mounting hole, and an annular gap (212) is formed between the top of the inner wall of the mounting hole (210) and the developing member (1); In step S2, when welding is performed at the joint between the developing ring (21) and the developing member (1), the weld (100) is located within the annular gap (212) and does not protrude from the top of the developing ring (21); or the weld (100) completely covers the annular gap (212), and the inner side edge and the outer side edge of the weld (100) are respectively located radially inward and radially outward of the annular gap (212).

3. The method according to claim 1, characterized in that In step S1, when the developing component (1) is pressed into the mounting hole (210), a punching force is provided to the developing component (1) through a punching head (32), wherein: The bottom end of the punch head (32) is provided with an annular protrusion (3211) capable of limiting the position of the developing member (1) at the joint between the developing ring (21) and the developing member (1) to form an annular gap (212); when the punch head (32) applies pressure to the developing ring (21), the outer contour of the annular protrusion (3211) can be embedded in the top position of the hole wall of the mounting hole (210), and the pressure is stopped when the developing member (1) is flush with the developing ring (21); Alternatively, the bottom end of the punch head (32) is a spherical bottom end (3212) capable of forming a concave spherical groove (11) at the top end of the developing member (1); the concave spherical groove (11) is located in the mounting hole (210), and the projection of the spherical bottom end (3212) in the vertical direction covers the mounting hole (210); Alternatively, the bottom end of the punch head (32) is a planar bottom end (3213); the end surface of the developing ring (21) facing the punch head (32) is formed as a plane, or the end surface of the developing ring (21) facing the punch head (32) is provided with a groove (213) capable of accommodating the planar bottom end (3213), and the mounting hole (210) is located on the bottom surface of the groove (213).

4. The method according to claim 2, characterized in that: In step S2, when welding is performed at the joint between the developing ring (21) and the developing member (1): A first annular weld (101) is provided in the first annular welding area; the outer side and the inner side of the first annular weld (101) are respectively a first outer side (1011) and a first inner side (1012); A second annular weld (102) is provided in the second annular welding area; the outer side and the inner side of the second annular weld (102) are respectively a second outer side (1021) and a second inner side (1022); The radial dimensions of the first outer edge (1011), the second outer edge (1021), the first inner edge (1012), and the second inner edge (1022) are sequentially reduced so that the annular overlapping area (103) of the first annular weld (101) and the second annular weld (102) covers the annular gap (212).

5. The method according to claim 4, characterized in that When the first annular weld (101) is arranged in the first annular welding area, its welding route is a first spiral curve (a), and the spiral center of the first spiral curve (a) moves circumferentially along the center ring of the first annular welding area; and / or, When the second annular weld (102) is arranged in the second annular welding area, its welding route is a second spiral curve (b), and the spiral center of the second spiral curve (b) moves circumferentially along the center ring of the second annular welding area.

6. The method according to claim 2, characterized in that In step S1: Before the developing component (1) is pressed into the mounting hole (210): the developing component (1) is a spherical or cylindrical structure, the mounting hole (210) is a through hole structure with an inlet end cross section equal to or larger than an outlet end cross section, and the cross-sectional shape of the through hole structure is circular; or the developing component (1) is an ellipsoidal or ellipsoidal structure, the mounting hole (210) is a through hole structure with an inlet end cross section equal to or larger than an outlet end cross section, and the cross-sectional shape of the through hole structure is elliptical; After the developing component (1) is pressed into the mounting hole (210), the developing component (1) is nested in the mounting hole (210) and is interference-fitted therewith, and the developing component (1) is in a columnar structure adapted to the mounting hole (210).

7. The method according to claim 1, characterized in that In step S2, the depth of welding corresponding to the annular gap (212) is 1 / 4 to 3 / 4 of the height of the mounting hole (210).

8. The method according to claim 1, characterized in that In step S1, when the developing member (1) is pressed into the mounting hole (210), a punching head (32) moving from top to bottom provides a punching force for the developing member (1), and a cylinder (35) provides power for the punching head (32). Before the punching starts, the air pressure is set to any value in the range of 1.4 MPa to 1.8 MPa, and the punching time is adjusted to any value in the range of 2.5S to 3.5S. In step S2, when welding is performed at the joint between the developing ring (21) and the developing member (1), the welding point diameter parameter is any value in the range of 0.3 mm to 0.7 mm, the welding speed parameter is any value in the range of 6 Hz to 10 Hz, the welding power is any value in the range of 230 to 270 V, and the welding depth is any value in the range of 1.5 to 3.5 ms.

9. The method according to claim 1, characterized in that: In step S2, before welding is performed at the joint between the developing ring (21) and the developing member (1), the following preparation steps are included: Step S021: sleeve the collar (42) onto the welding shaft (41) and fix it thereon, wherein a positioning groove (421) is provided on the side of the collar (42); Step S022: sleeve the shaft sleeve (43) on the welding shaft (41), the side of the shaft sleeve (43) is provided with a positioning protrusion (431), and the positioning protrusion (431) is located in the positioning groove (421) to correspond to the position of the developing ring to be welded; Step S023: After adjusting and confirming the welding parameters and welding position of the welding equipment on the shaft sleeve (43), the shaft sleeve (43) is removed, and the developing ring to be welded is placed in the positioning groove (421) of the sleeve ring (42) for limiting.

10. The method according to claim 9, characterized in that In step S023: Adjusting the welding parameters includes adjusting the focal length so that the laser hits the sleeve (43); And / or, adjusting the welding position includes adjusting a frame line position on a display of the welding device to determine a focus position.

11. The method according to claim 1, characterized in that: In step S2, when welding the joint between the developing ring (21) and the developing member (1), the developing material located at or near the annular gap (212) between the developing ring (21) and the developing member (1) is melted into the annular gap (212) by laser.

12. The method according to claim 1, characterized in that In step S1, when the developing component (1) is pressed into the mounting hole (210), the blood vessel stent (2) is positioned by a punching tool (3), wherein: The punching tool (3) is provided with a first positioning groove (301) capable of positioning the support body (22) of the blood vessel stent (2), and a second positioning groove (302) capable of positioning the developing ring (21) of the blood vessel stent (2).

13. The method according to claim 12, characterized in that The punching tool (3) comprises a punching base (31), the second positioning groove (302) is arranged on the top side of the punching base (31), and the side of the punching base (31) is provided with a plurality of strip grooves (303) for accommodating other developing rings (21), wherein the other developing rings (21) are developing rings of the vascular stent other than the developing ring to be pressed at the moment, the plurality of strip grooves (303) are located below the second positioning groove (302) and are arranged in sequence along the arc track (C), and the length direction (L) of each strip groove (303) is respectively located in the radial direction of different positions of the arc track (C).

14. The method according to claim 13, characterized in that The stamping base (31) comprises: A base (311), the second positioning groove (302) being arranged on a side edge of the top surface thereof; a gasket (312) located on the top of the base (311); a third positioning groove (304) is provided in the area of ​​the gasket (312) located above the second positioning groove (302); and an edge of a projection area of ​​the third positioning groove (304) on the base (311) is located radially outside the second positioning groove (302); The punch head (32) used for applying pressure to the developing member (1) and the developing ring (21) comprises: A columnar body (322), wherein a projection area of ​​the columnar body (322) on the gasket (312) covers the third positioning groove (304); The punching end head (321) is located at the bottom end of the columnar body (322) and is aligned vertically with the second positioning groove (302), and the projection area of ​​the punching end head (321) on the gasket (312) is located in the third positioning groove (304).

15. A vascular stent, characterized in that: The developing structure of the vascular stent is manufactured by the method according to any one of claims 1 to 14, and the developing structure is flush with the developing ring in the axial direction of the vascular stent.

16. According to the vascular stent according to claim 15, the developing structure comprises a rivet portion and a welding portion, the rivet portion is located in the mounting hole of the vascular stent, the welding portion is arranged around the rivet portion, and the developing structure is fixed to the mounting hole through the rivet portion and the welding portion.

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