Bevel bracket

Abstract

The present invention provides an oblique stent, comprising a front section. In the planar unfolding structure of the front section, the connecting lines between the tops of a plurality of protrusions form at least two linear contour lines or at least two nonlinear contour lines, so that the opening inclined surface formed by the free opening end surface of the oblique stent can adapt to the physiological structure at the bifurcation of the natural cavity of the human body, thereby avoiding the problem of affecting the flow of fluid substances on the opposite side, such as blood flow, caused by the protrusion of the proximal end of the stent in the prior art, or the problem of natural cavity restenosis caused by the stent being too far away from the bifurcation, so that the stent cannot effectively cover the lesion position and cannot provide reasonable radial support force.

Description

Technical Field

[0001] The invention relates to the technical field of medical devices, in particular to an oblique-mouth bracket. Background Art

[0002] At present, cardiovascular disease has become the number one killer threatening human life and health. Vascular stent interventional treatment is the fastest growing and most widely used clinical method for the effective treatment of vascular occlusion diseases, with the characteristics of minimally invasive and high efficiency.

[0003] Vascular stents are used to place in the diseased segment of the lumen to support the narrowed and occluded segment of the lumen and keep the lumen open. Among the performance indicators of vascular stents, the flexibility and support performance of the stent play a vital role in the operation process and the clinical effect after the operation. The flexibility of the stent will affect the bending ability of the stent in the delivery catheter. Poor flexibility will straighten or even damage the blood vessels, or make it difficult to reach the lesion site. The support of the vascular stent will affect the long-term service ability of the stent. If the support of the stent is very poor, it will not be able to open the narrowed blood vessels, or even if it can be opened during the operation, the incidence of restenosis after the operation will be relatively high.

[0004] A Chinese patent with publication number CN105167881B discloses a vascular stent with resistance to longitudinal deformation, wherein adjacent annular supports at the proximal end of the vascular stent are connected by linear connecting ribs, and the middle and distal ends are connected by S-shaped connecting ribs, so as to take into account both the longitudinal strength and flexibility of the vascular stent.

[0005] However, due to the physiological curvature of the blood vessels, when the above-mentioned vascular stent is placed close to the vascular bifurcation, the front end of the vascular stent will protrude into the proximal blood vessel, thereby affecting the blood flow in the opposite blood vessel; if the front end of the above-mentioned vascular stent is not placed protruding into the proximal blood vessel, its front section structure cannot adapt to the physiological structure of the vascular bifurcation, and therefore can neither completely cover the lesion nor provide reasonable radial support force, which can easily cause restenosis of the blood vessel.

[0006] Therefore, it is necessary to design a new type of oblique bracket to avoid the above problems existing in the prior art. Summary of the invention

[0007] The purpose of the present invention is to provide an oblique-mouth stent for use in a natural cavity of the human body, so as to provide sufficient radial support force to avoid causing vascular restenosis problems without affecting contralateral blood flow, and is particularly suitable for application scenarios at vascular bifurcations.

[0008] To achieve the above-mentioned purpose, the oblique-mouth bracket of the present invention includes a front section, the free open end surface of the front section includes a plurality of protrusions to form an open inclined surface, and the open inclined surface is inclined to the axis of the front section; in the planar unfolding structure of the front section, the connecting line between the top ends of the plurality of protrusions forms at least two linear contour lines or at least two nonlinear contour lines, and the nonlinear contour line includes an arc contour line, and the front section is formed by connecting a plurality of closed-loop structures, and in the planar unfolding structure of the front section, the maximum radial length of the closed-loop structure forming the free open end surface of the front section is greater than the maximum radial length of other closed-loop structures except the closed-loop structure forming the free open end surface of the front section. Its beneficial effect is: further strengthening the radial supporting force, the front section is composed of a number of closed-loop structures connected together, and the several closed-loop structures form a number of support units along the axial direction of the front section, and each group of support units has the same number of closed-loop structures. Its beneficial effect is: strengthening the radial supporting force, in the planar unfolding structure of the front section, the adjacent support units located on the same side of the axis of the front section are an inner support unit close to the axis of the front section and an outer support unit far away from the axis of the front section, and the strength of the inner support unit is greater than the strength of the outer support unit.

[0009] The beneficial effect of the oblique-mouth stent of the present invention is that: in the planar unfolded structure of the front section, the connecting lines between the top ends of the plurality of protrusions form at least two linear contour lines or at least two nonlinear contour lines, so that the opening inclined surface formed by the free opening end surface of the oblique-mouth stent can adapt to the physiological structure at the bifurcation of the natural cavity of the human body, thereby avoiding the problem of affecting the flow of contralateral fluid substances, such as blood flow, caused by the protrusion of the proximal end of the stent in the prior art, or the problem of natural cavity restenosis caused by the stent being too far away from the bifurcation, which makes the stent unable to effectively cover the lesion position and unable to provide reasonable radial support force.

[0010] Preferably, in the planar unfolded structure of the front section, the arc contour line is bent away from the axis of the front section. The beneficial effect is that it is conducive to enhancing the radial supporting force of the oblique bracket.

[0011] Further preferably, in the planar unfolded structure of the front section, adjacent arc-shaped contour lines converge at the same point or have different proximal ends, and the proximal end is an end of the arc-shaped contour line close to the axis of the front section.

[0012] Further preferably, in the planar unfolded structure of the front section, an angle between a tangent of the arcuate contour line formed by the proximal end of the arcuate contour line and a perpendicular to the axis of the front section formed by the proximal end is 0-70 degrees.

[0013] Preferably, in the planar unfolded structure of the front section, adjacent linear contour lines have different proximal ends, and the proximal end is an end of the linear contour line close to the axis of the front section. The beneficial effect is that it is conducive to enhancing the radial support force of the oblique stent.

[0014] Further preferably, in the planar unfolded structure of the front section, an acute angle between the linear contour line and the axis of the front section is 20-80 degrees.

[0015] Preferably, the number of any one of the linear contour lines or the nonlinear contour lines is an even number, and they are mirror images of each other relative to the axis of the front section. The beneficial effect is that it is conducive to the uniform distribution of radial supporting force.

[0016] Preferably, in the planar unfolded structure of the front section, there are a number of transition protrusions between adjacent linear contour lines or nonlinear contour lines, and the line connecting the protrusion tops of the transition protrusions forms a straight contour line, and the angle between the straight contour line and the axis of the front section is 70-90 degrees. The beneficial effect is that the angle between the straight contour line and the axis of the front section is controlled to be 70-90 degrees, which is not easy to affect the flow of blood or fluid substances on the opposite side.

[0017] Preferably, the oblique bracket further comprises a marking portion, which is arranged on the free opening end surface of the front section and is riveted or filled with developing metal. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of a vascular stent in the prior art being placed in a human body;

[0019] Figure 2 This is a schematic structural diagram of an oblique bracket according to an embodiment of the present invention;

[0020] Figure 3 for Figure 2 The structural schematic diagram of the front section shown;

[0021] Figure 4 for Figure 3 The front section shown is a schematic diagram of a planar unfolded structure formed by cutting along the AA direction;

[0022] Figure 5 for Figure 2 The schematic diagram of the oblique stent implanted in the human body is shown;

[0023] Figure 6 It is a structural schematic diagram of the front section of another oblique bracket according to an embodiment of the present invention;

[0024] Figure 7 for Figure 6The front section shown is a schematic diagram of a planar unfolded structure formed by cutting along the AA direction;

[0025] Figure 8 It is a structural schematic diagram of the front section of another oblique bracket according to an embodiment of the present invention;

[0026] Fig. 9 for Figure 8 The front section shown is a schematic diagram of a planar unfolded structure formed by cutting along the AA direction. DETAILED DESCRIPTION

[0027] In order to make the purpose, technical solutions and advantages of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention. Unless otherwise defined, the technical terms or scientific terms used herein should be understood by people with general skills in the field to which the present invention belongs. "Including" and similar words used in this article mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects.

[0028] Figure 1 The figure is a schematic diagram of a vascular stent in the prior art being implanted in a human body.

[0029] Reference Figure 1 , the first blood vessel 11, the second blood vessel 12 and the third blood vessel 13 in the human body intersect to form a blood vessel bifurcation structure. When the lesion site exists at a position of the blood vessel bifurcation structure close to the first blood vessel 11, it is necessary to insert the vascular stent 14 into the first blood vessel 11 and reach the blood vessel bifurcation structure. Since the front end face 141 of the vascular stent 14 is perpendicular to the axis of the vascular stent 14 (not shown in the figure), in order to place the vascular stent 14 in the blood vessel bifurcation structure and make the vascular stent 14 generate sufficient supporting force to maintain the position relative to the first blood vessel 11 unchanged, the front end face 141 needs to extend out of the intersection of the first blood vessel 11 and the second blood vessel 12, but this insertion method can easily significantly affect the blood flow of the second blood vessel 12 and the third blood vessel 13. If the vascular stent 14 is inserted into the first blood vessel 11 and the front end face 141 is away from the blood vessel bifurcation structure, the lesion cannot be completely covered, and it is also easy to cause the problem of restenosis of the blood vessel due to insufficient proximal supporting force of the vascular stent 14.

[0030] In order to solve the problems existing in the prior art, an embodiment of the present invention provides an oblique-mouth stent applied to a natural cavity of a human body, wherein the oblique-mouth stent includes a front section.

[0031] The front section described in the embodiment of the present invention means that the oblique stent is composed of at least two tubular structures, wherein the tubular structure at one end is the front section. The rigidity of the front section is greater than that of the other tubular structures. After the oblique stent is placed in the natural cavity of the human body, the front section can still undergo a recoverable deformation under the squeezing action of the natural cavity of the human body to adapt to the physiological curvature structure of the natural cavity of the human body.

[0032] In the embodiment of the present invention, the natural cavities of the human body include blood vessels, digestive tract, urinary tract and reproductive tract.

[0033] In an embodiment of the present invention, the free opening end surface of the front section includes a plurality of protrusions to form an opening inclined surface. The connecting line between the tops of the plurality of protrusions forms a linear contour line or a nonlinear contour line, and the linear contour line and the nonlinear contour line are inclined to the axis of the front section.

[0034] Figure 2 The figure is a schematic structural diagram of an oblique bracket according to an embodiment of the present invention. Figure 3 for Figure 2 The structural schematic diagram of the front section is shown.

[0035] Reference Figure 2 The oblique stent 2 is tubular and includes a front section 21 and a flexible section 22 that are connected to each other. The front section 21 is formed by connecting a plurality of closed-loop structures 211, and the flexible section 22 is formed by connecting a plurality of V-shaped open-loop structures 221, and the two are connected by a connecting structure 222. After the oblique stent 2 is placed in the bifurcation of a natural cavity of the human body, such as the bifurcation of a blood vessel, the front section 21 mainly provides a supporting force to ensure that the oblique stent 2 will not be significantly displaced relative to the bifurcation while adapting to the physiological curvature structure of the blood vessel; the flexible section 22 mainly provides good wall adhesion performance.

[0036] Specifically, the front section 21 has a uniform outer diameter.

[0037] Reference Figure 2 and Figure 3, the free open end of the front section 21 includes a plurality of protrusions 31 and a plurality of transition protrusions 32. The free open end of the front section 21 is the end of the front section 21 that is not connected to the flexible portion 22. The free open end of the front section 21 includes an opening inclined surface (not shown in the figure) surrounded by the plurality of protrusions 31 and a vertical surface (not shown in the figure) surrounded by the plurality of transition protrusions 32. Among them, the opening inclined surfaces (not shown in the figure) surrounded by the plurality of protrusions 31 are all inclined to the axis 33 of the front section 21, and the vertical surfaces (not shown in the figure) surrounded by the plurality of transition protrusions 32 are perpendicular to the axis 33.

[0038] Specifically, the axis 33 is the central axis of the front section 21 .

[0039] The “planar unfolding structure” described in the embodiment of the present invention refers to Figure 3 Specifically, it refers to a structure formed by cutting the side wall of the front section 21 along the cutting direction AA, and then spreading it on the same plane without wrinkles according to the actual shape and size of the plane per unit area. The side wall of the front section 21 is cut along the cutting direction AA so that the plane unfolded structure of the front section 21 is an axisymmetric structure relative to the axis 33.

[0040] Specifically, the cutting direction AA is parallel to the axis 33, and the intersection of the cutting line (not shown in the figure) formed along the cutting direction AA on the side wall of the front section 21 and the edge of the opening inclined surface (not shown in the figure) surrounded by the plurality of protrusions 31 is compared with other cutting lines parallel to the axis 33 and intersecting with the edge of the opening inclined surface (not shown in the figure) surrounded by the plurality of protrusions 31. Figure 3 The cutting direction AA shown is at the maximum vertical distance from the axis 33 to the intersection of the cutting line (not shown in the figure) formed by the side wall of the front section 21 and the edge of the opening inclined surface (not shown in the figure) surrounded by the plurality of protrusions 31 .

[0041] In some embodiments of the present invention, the number of any one of the linear contour lines and the nonlinear contour lines is at least 2.

[0042] In some embodiments of the present invention, the number of any one of the linear contour lines and the nonlinear contour lines is an even number and they are mirror images of each other relative to the axis 33 of the front section 21 .

[0043] Figure 4 for Figure 3 The front section shown is a schematic diagram of a planar unfolded structure formed by cutting along the AA direction.

[0044] In some embodiments of the present invention, in the planar unfolded structure of the front section 21, the connecting lines between the tops of different protrusions 31 form different linear contours, and the different linear contours have different proximal ends. The proximal end refers to the end of the linear contour close to the axis 33.

[0045] Specifically, refer to Figure 3 and Figure 4 In the planar unfolded structure of the front section 21, the different linear contour lines are respectively adjacent first linear contour lines 41 and second linear contour lines 42. The first linear contour lines 41 and the second linear contour lines 42 are both inclined to the axis 33 and are located on both sides of the axis 33. The first linear contour lines 41 and the second linear contour lines 42 have different proximal ends, namely, a first proximal end 44 and a second proximal end 45. The first linear contour lines 41 and the second linear contour lines 42 are mirror images of each other relative to the axis 33.

[0046] In some embodiments of the present invention, in the planar unfolded structure of the front section 21, there are a number of transition protrusions between adjacent linear contour lines or nonlinear contour lines, and the connecting line between the protrusion tops of the number of transition protrusions forms a straight contour line.

[0047] Specifically, refer to Figure 3 and Figure 4 The connecting line between the top ends of the plurality of transition protrusions 32 forms a straight contour line 43 , and the straight contour line 43 is perpendicular to the axis 33 .

[0048] Figure 5 for Figure 2 The schematic diagram of the oblique stent implanted in the human body is shown.

[0049] Reference Figure 3 and Figure 5 When the oblique stent 2 is placed in the first blood vessel 11 and reaches the vascular bifurcation structure, since the first linear contour line 41 and the second linear contour line 42 are both inclined to the axis 33, the oblique stent 2 is easily placed at the bifurcation of the vascular bifurcation structure to adapt to the physiological structure of the vascular bifurcation structure, while minimizing the impact of the structure extending out of the intersection of the first blood vessel 11 and the second blood vessel 12 on blood flow, and can effectively cover the lesion position to avoid the problem of restenosis of the blood vessel caused by insufficient proximal support.

[0050] In some embodiments of the present invention, the angle between the straight contour line 43 and the axis of the front section 21 is 70-90 degrees. If the angle between the straight contour line 43 and the axis of the front section 21 is too small, the front section 21 of the oblique bracket 2 cannot generate sufficient radial support force.

[0051] More specifically, the angle between the straight contour line 43 and the axis of the front section 21 is any one of 80 degrees and 85 degrees.

[0052] In some embodiments of the present invention, in the planar unfolded structure of the front section 21, the acute angle between the linear contour line and the axis 33 of the front section 21 is 20-80 degrees, so as to conform to the anatomical morphology of the vascular bifurcation, achieve the best vascular coverage effect, avoid minimizing the impact of the structure extending out of the intersection of the first blood vessel 11 and the second blood vessel 12 on blood flow, and avoid the problem of vascular restenosis caused by insufficient proximal support force.

[0053] If the acute angle between the linear contour and the axis 33 of the front section 21 is too large, in order to facilitate placement in the body and prevent displacement, the oblique bracket 2 must be like Figure 1 The vascular stent 14 is placed as shown, so that the front section 21 is more likely to extend out of the intersection of the first blood vessel 11 and the second blood vessel 12, thereby affecting the blood flow on the opposite side, and causing unnecessary harm to the human body during the insertion into the human body; if the acute angle between the linear contour line and the axis 33 of the front section 21 is too small, the front end of the oblique stent 2 is too sharp and cannot generate sufficient radial supporting force, which is easy to cause vascular restenosis problems.

[0054] In some embodiments of the present invention, the acute angle between the linear contour line and the axis 33 of the front section 21 is any one of 30 degrees, 40 degrees, 50 degrees, 60 degrees and 70 degrees.

[0055] In some embodiments of the present invention, the maximum radial length of the closed-loop structure forming the free open end surface of the front section 21 is greater than the maximum radial length of other closed-loop structures except the closed-loop structure forming the free open end surface of the front section 21 .

[0056] Specifically, refer to Figure 4 In the planar unfolded structure of the front section 21, the maximum radial length L of the closed-loop structure corresponding to the protrusions of the first linear contour line 41 and the second linear contour line 42 is greater than the maximum radial length of other closed-loop structures, and the other closed-loop structures refer to the closed-loop structures corresponding to the protrusions forming the straight contour line 43.

[0057] In some embodiments of the present invention, the closed-loop structure is an N-gon, N is a positive integer greater than or equal to 3, and the length of each side of the closed-loop structure is 2-7 mm.

[0058] Specifically, refer to Figure 4 , the closed-loop structure is rhombus-shaped.

[0059] In some embodiments of the present invention, referring to Figure 2 The oblique bracket 2 also includes a marking portion 23, which is arranged on the free opening end surface of the front section 21 and is riveted or filled with developing metal.

[0060] Figure 6 It is a schematic structural diagram of the front section of another oblique bracket according to an embodiment of the present invention. Figure 7 for Figure 6 The front section shown is a schematic diagram of a planar unfolded structure formed by cutting along the AA direction.

[0061] In some embodiments of the present invention, in the planar unfolded structure of the front section 21, the arcuate contour line is bent away from the axis 33. The connecting lines between the protrusion tops of different protrusion groups form different arcuate contour lines, and the different arcuate contour lines converge at the same point or have different proximal ends, and the proximal end is an end of the arcuate contour line close to the axis 33.

[0062] Reference Figure 2 and Figure 6 , Figure 6 The front section shown is Figure 2 The difference of the front section shown is that: Figure 6 In the front section shown, the plurality of protrusions 31 form an opening inclined surface (not shown in the figure) with an arc-shaped edge and inclined to the axis 33 at the free opening end surface of the front section 21 .

[0063] Reference Figure 6 and Figure 7 , Figure 6 In the planar unfolded structure of the front section shown, the connecting line between the top ends of the plurality of protrusions 31 forms an adjacent first arc contour line 71 and a second arc contour line 72, and the first arc contour line 71 and the second arc contour line 72 are both bent away from the axis 33 and meet at the same intersection point 73. The intersection point 73 is the proximal end of the first arc contour line 71 and the proximal end of the second arc contour line 72.

[0064] Specifically, the first arc contour line 71 and the second arc contour line 72 are mirror images relative to the axis 33. Taking the first arc contour line 71 as an example, the tangent formed by the proximal end of the first arc contour line 71 is the first tangent line 74, and the perpendicular line to the axis 33 formed by the intersection point 73 is the first perpendicular line 75.

[0065] In some embodiments of the present invention, the angle between the first tangent line 74 and the first perpendicular line 75 is 0-70 degrees.

[0066] Figure 8It is a structural schematic diagram of the front section of another oblique bracket according to an embodiment of the present invention. Fig. 9 for Figure 8 The front section shown is a schematic diagram of a planar unfolded structure formed by cutting along the AA direction.

[0067] Reference Figure 6 and Figure 8 , Figure 8 The front section shown is Figure 6 The difference of the front section shown is that: Figure 8 The free opening end surface of the front section shown includes not only an opening inclined surface formed by the plurality of protrusions 31 and inclined to the axis 33 , but also a plane formed by the plurality of transition protrusions 32 and perpendicular to the axis 33 .

[0068] Reference Figure 8 and Fig. 9 , Figure 8 In the planar unfolded structure of the front section shown, the connecting line between the top ends of the plurality of protrusions 31 forms a third arc contour line 91 and a fourth arc contour line (not shown in the figure), and the third arc contour line 91 and the fourth arc contour line (not shown in the figure) are both bent away from the axis 33 and located on both sides of the axis 33. The third arc contour line 91 and the fourth arc contour line (not shown in the figure) are mirror images of each other relative to the axis 33.

[0069] Specifically, the third arc contour line 91 and the fourth arc contour line (not shown in the figure) have different proximal ends, which are respectively a third proximal end 92 and a fourth proximal end 93. Taking the fourth arc contour line (not shown in the figure) as an example, the tangent line formed by the third proximal end 92 is a second tangent line 96, and the perpendicular line to the axis 33 formed by the second tangent line 96 is a second perpendicular line 95.

[0070] In some embodiments of the present invention, the angle between the second tangent line 96 and the second perpendicular line 95 is 0-70 degrees.

[0071] In the embodiment of the present invention, referring to 4, Figure 7 and Fig. 9 The several closed-loop structures forming the front section 21 form several groups of support units (not shown in the figure) along the axial direction of the front section 21, and the several groups of support units (not shown in the figure) are all parallel to the axis 33.

[0072] The Chinese invention patent application with publication number CN109793600A also discloses a vascular stent with an inclined end face. However, among the several axial support units parallel to the axis of the front section in the planar unfolding structure of the front section, the number of closed-loop structures in the axial support units close to the axis of the front section is greater than the number of closed-loop structures far from the front section, so that the formed stent end face presents an everted structure. On the one hand, the formation of such an everted structure is not conducive to providing sufficient radial supporting force; on the other hand, the formation of the everted structure is not conducive to good wall adhesion performance and can easily cause unnecessary damage to natural cavities of the human body such as blood vessels.

[0073] In some embodiments of the present invention, each group of support units has the same number of closed-loop structures, so that the front section 21 will not form an everted structure such as CN109793600A, thereby ensuring that sufficient radial support force can be provided without causing unnecessary damage to the natural cavity of the human body.

[0074] Specifically, Figure 4 , Figure 7 and Fig. 9 In the front section shown, each group of support units has four closed-loop structures.

[0075] To ensure that each group of support units has the same number of closed-loop structures, refer to Figure 4 , Figure 7 and Fig. 9 In any of the front sections shown, at least part of the closed-loop structures in each group of support units are elongated diamond structures along the direction of the axis 33, and the number of elongated diamond structures in the support units closer to the axis 33 is greater and the degree of elongation is greater, so that this part of the support units is more likely to deform than other support units, which is not conducive to the uniform distribution of radial support force of the front section 21.

[0076] In the planar unfolded structure of the front section 21, adjacent support units located on the same side of the axis 33 are an inner support unit close to the axis 33 and an outer support unit far from the axis of the front section. In order to make the radial support force of the front section 21 evenly distributed, the strength of the inner support unit is made greater than that of the outer support unit for mechanical reinforcement, which is conducive to the uniform distribution of the radial support force of the front section 21.

[0077] In some embodiments of the present invention, taking a number of support units located on the same side of the axis 33 as an example, the mass of each support unit is increased sequentially starting from the support unit farthest from the axis 33 to achieve the mechanical reinforcement.

[0078] Although the embodiments of the present invention are described in detail above, it is obvious to those skilled in the art that various modifications and variations can be made to these embodiments. However, it should be understood that such modifications and variations are within the scope and spirit of the present invention as described in the claims. Moreover, the present invention described herein may have other embodiments and may be implemented or realized in a variety of ways.

Claims

1. An oblique-mouth stent, applied to a natural cavity of a human body, the oblique-mouth stent comprising a front section, characterized in that: The free opening end surface of the front section includes a plurality of protrusions to form an opening inclined surface, and the opening inclined surface is inclined to the axis of the front section; In the planar unfolded structure of the front section, the connecting lines between the top ends of the plurality of protrusions form at least two linear contour lines or at least two nonlinear contour lines, and the nonlinear contour lines include arc contour lines; The front section is formed by connecting a number of closed-loop structures. In the planar unfolded structure of the front section, the maximum radial length of the closed-loop structure forming the free open end face of the front section is greater than the maximum radial length of other closed-loop structures except the closed-loop structure forming the free open end face of the front section. The front section is formed by connecting a number of closed-loop structures. The number of closed-loop structures form a number of groups of support units along the axial direction of the front section, and each group of support units has the same number of closed-loop structures. In the planar unfolded structure of the front section, adjacent support units located on the same side of the axis of the front section are an inner support unit close to the axis of the front section and an outer support unit far from the axis of the front section, and the strength of the inner support unit is greater than the strength of the outer support unit.

2. The oblique bracket according to claim 1, characterized in that: In the planar unfolded structure of the front section, the arc-shaped contour line is bent away from the axis of the front section.

3. The oblique bracket according to claim 2, characterized in that: In the planar unfolded structure of the front section, adjacent arc-shaped contour lines converge at the same point or have different proximal ends, and the proximal end is an end of the arc-shaped contour line close to the axis of the front section.

4. The oblique bracket according to claim 3, characterized in that: In the planar unfolded structure of the front section, an angle between a tangent line of the arcuate contour line formed by the proximal end of the arcuate contour line and a perpendicular line to the axis of the front section formed by the proximal end is 0-70 degrees.

5. The oblique bracket according to claim 1, characterized in that: In the planar unfolded structure of the front section, adjacent linear contour lines have different proximal ends, and the proximal end is an end of the linear contour line close to the axis of the front section.

6. The oblique bracket according to claim 5, characterized in that: In the planar unfolded structure of the front section, the acute angle between the linear contour line and the axis of the front section is 20-80 degrees.

7. The oblique bracket according to claim 1, characterized in that: The number of any one of the linear contour lines or the nonlinear contour lines is an even number, and they are mirror images of each other relative to the axis of the front section.

8. The oblique bracket according to claim 1, characterized in that: In the planar unfolded structure of the front section, there are several transition protrusions between adjacent linear contour lines or nonlinear contour lines, and the connecting line between the protrusion tops of the several transition protrusions forms a straight contour line, and the angle between the straight contour line and the axis of the front section is 70-90 degrees.

9. The oblique bracket according to claim 1, characterized in that: It also includes a marking portion, which is arranged on the free opening end surface of the front section and is riveted or filled with developing metal.

Images