Dead-space-free U-shaped connector device for hemodialysis

Abstract

The invention discloses a dead-space-free U-shaped connector device for hemodialysis, which comprises a U-shaped connector tube, the U-shaped connector tube comprises arc-shaped sections at two corners and three straight sections, namely an inlet straight section, a first arc-shaped section, a middle straight section, a second arc-shaped section and an outlet straight section, a continuous through spiral flow guide groove is formed from the inlet straight section to the inner wall of the second arc-shaped section, so that fluid is forced to generate spiral motion to scour the inner wall; the invention belongs to the technical field of medical instruments, and aims to solve the problems that in the prior art, when passing through a curve, the flow velocity difference between the inner side and the outer side is generated due to the centrifugal effect, turbulent flow is easily formed in an outer side high-speed area, and blood retention is formed in an inner side low-speed area. And in combination with the strong scouring effect of the dense flow guide plates on the outer side, formation of a retention area is avoided, the middle diameter is increased, the circulation sectional area can be enlarged, and the outer side flow speed is reduced.

Description

Technical Field

[0001] This invention relates to the field of medical device technology, specifically to a U-shaped connector device for dead space-free hemodialysis. Background Technology

[0002] The U-shaped connector in hemodialysis tubing, as a key component connecting the patient's vascular access to the dialyzer, directly affects the efficiency and safety of treatment due to its hydrodynamic performance. However, traditional U-shaped connectors suffer from the following technical bottlenecks due to structural design flaws:

[0003] The U-shaped connector bend area typically employs a constant diameter design, resulting in a significant velocity difference between the inner and outer sides of the blood as it flows through the bend due to centrifugal effect. The high-velocity outer zone is prone to turbulence, while the low-velocity inner zone leads to blood stagnation (dead space volume ≥0.3mL), creating a breeding ground for thrombosis.

[0004] Therefore, to address the shortcomings of existing requirements, we propose a U-shaped connector device for dead space-free hemodialysis. Summary of the Invention

[0005] Therefore, the present invention provides a U-shaped connector device for dead space-free hemodialysis to solve the above-mentioned problem in the prior art where a significant difference in flow velocity between the inside and outside of the blood due to centrifugal effect occurs when blood flows through a bend.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] According to a first aspect of the present invention, a U-shaped connector device for dead space-free hemodialysis includes a U-shaped connector tube, the U-shaped connector tube comprising two curved sections and three straight sections, namely an inlet straight section, a first curved section, a middle straight section, a second curved section, and an outlet straight section, and further comprising:

[0008] A continuous spiral guide groove is provided on the inner wall from the straight section of the inlet to the second arc section, which forces the fluid to generate a spiral motion to flush the inner wall and eliminate dead space;

[0009] The first guide plate group, which is set in the first arc segment and the second arc segment, is spiral-shaped and is used to break up large-scale eddies and maintain spiral flow. The first guide plate group includes multiple spiral guide plates, which are distributed in a ring inside the first arc segment and the second arc segment. The arrangement density increases from the inside to the outside of the arc segment to guide the fluid to flow along the spiral trajectory, break up large-scale eddies and convert turbulent kinetic energy into laminar kinetic energy.

[0010] The radii of curvature of the first and second arc segments increase from both ends toward the center of the arc section, balancing the pressure distribution in the curve area and suppressing turbulence generation.

[0011] Furthermore, the pitch of the spiral guide groove gradually increases along the fluid direction, thereby achieving adaptive attenuation of the spiral motion intensity along the flow direction.

[0012] Furthermore, the radius of curvature at the middle of the first and second arc segments is 1.5 to 2 times the radius of curvature at both ends.

[0013] Furthermore, the inner wall of the straight section at the outlet is provided with a second guide plate group, and the first section of the second guide plate group overlaps the end of the first guide plate group by 15% to 25%. The pitch of the second spiral guide plate of the second guide plate group is greater than the pitch of the first spiral guide plate, which is used to gradually attenuate the rotational momentum of the fluid and realize the turbulent transition from the spiral flow to the horizontal flow.

[0014] Furthermore, based on the curve centerlines of the first and second arc segments, the spiral inclination angle β of the first spiral guide plate is 10° to 30°, D1 is the diameter of the straight section, and the height h1 of the first spiral guide plate is 0.1D1 to 0.2D1.

[0015] Furthermore, the inner wall of the straight section of the outlet is provided with a superhydrophilic silica layer with a contact angle ≤10° and a thickness of 50~100nm.

[0016] Furthermore, the superhydrophilic silica layer is doped with 0.1–0.3 wt% of silver nanoparticles with a particle size ≤50 nm, which are used to inhibit biofilm formation.

[0017] Furthermore, the inner wall of the spiral guide channel is covered with a high heparin loading layer, with a heparin density ≥1.5 μg / cm³. 2 .

[0018] Furthermore, the spiral guide plate of the second guide plate assembly is covered with a titanium nitride wear-resistant layer with a hardness ≥2000HV.

[0019] Furthermore, the U-shaped substrate of the U-shaped connector tube is made of transparent medical-grade polycarbonate or polyetheretherketone, with a light transmittance of ≥80%.

[0020] The present invention has the following advantages:

[0021] 1. The U-shaped connector device for dead space-free hemodialysis uses a variable diameter arc section, with the diameters at both ends gradually increasing towards the middle to balance the difference in centrifugal force. Combined with the strong scouring effect of the dense outer guide plates, it avoids the formation of stagnation zones. Increasing the diameter in the middle can expand the flow cross-sectional area and reduce the flow velocity on the outside, thereby reducing the difference in centrifugal force and making the pressure gradient tend to be gentle.

[0022] 2. The U-shaped connector device for dead space-free hemodialysis has a continuous spiral guide groove on the inner wall from the straight section at the inlet to the second arc section, which forces the fluid to generate spiral motion to flush the inner wall and eliminate dead space. The pitch gradually increases along the fluid direction, so as to realize the adaptive attenuation of the spiral motion intensity along the flow direction.

[0023] 3. The U-shaped connector device for dead space-free hemodialysis uses an alternating design of the first and second guide plate groups to gradually attenuate the rotational momentum of the fluid, achieving a turbulent transition from spiral flow to horizontal flow. At the same time, the asymmetrically arranged first guide plate group breaks large-scale eddies into micro-eddies, reducing turbulent kinetic energy. Attached Figure Description

[0024] Figure 1 This is a front view of a U-shaped connector device for dead space-free hemodialysis proposed in this invention;

[0025] Figure 2 This invention provides a U-shaped connector device for dead space-free hemodialysis. Figure 1 Internal view;

[0026] Figure 3 This is a cross-sectional view of the U-shaped connector tube of a U-shaped connector device for dead space-free hemodialysis proposed in this invention;

[0027] Figure 4 This is a front view of the first arc segment of a U-shaped connector device for dead space-free hemodialysis proposed in this invention;

[0028] Figure 5 This invention provides a U-shaped connector device for dead space-free hemodialysis. Figure 4 A sectional view;

[0029] Figure 6 This is a cross-sectional front view of the first guide plate assembly of a U-shaped connector device for dead space-free hemodialysis proposed in this invention;

[0030] Figure 7 This is an overall diagram of a U-shaped connector device for dead space-free hemodialysis proposed in this invention.

[0031] In the figure: 1. U-shaped connector pipe; 101. Inlet straight section; 102. First arc section; 103. Middle straight section; 104. Second arc section; 105. Outlet straight section; 2. Spiral guide channel; 3. First guide plate group; 4. Second guide plate group. Detailed Implementation

[0032] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0033] Example 1

[0034] Reference Figures 1-7 A U-shaped connector device for dead space-free hemodialysis includes a U-shaped connector tube 1. The U-shaped connector tube 1 includes two curved sections and three straight sections, namely an inlet straight section 101, a first curved section 102, a middle straight section 103, a second curved section 104, and an outlet straight section 105. The device is characterized by further comprising:

[0035] A continuous spiral guide groove 2 is provided on the inner wall from the straight section 101 at the inlet to the second arc section 104, which forces the fluid to generate a spiral motion to flush the inner wall and eliminate dead space.

[0036] The first guide plate group 3, which is set in the first arc segment 102 and the second arc segment 104, is spiral-shaped and is used to break up large-scale eddies and maintain spiral flow. The first guide plate group 3 includes multiple spiral guide plates, which are distributed in a ring inside the first arc segment 102 and the second arc segment 104. The arrangement density increases from the inside to the outside of the arc segment to guide the fluid to flow along the spiral trajectory, break up large-scale eddies and convert turbulent kinetic energy into laminar kinetic energy.

[0037] The radii of curvature of the first arc segment 102 and the second arc segment 104 increase from both ends toward the center of the arc section, respectively, to balance the velocity difference and pressure gradient between the inner and outer sides of the bend, suppress turbulence generation, and satisfy R2 / R1 = 1.5~2.0, where R1 is the radius of curvature at both ends and R2 is the radius of curvature at the center.

[0038] The inner wall of the straight section 105 at the outlet is provided with a second guide plate group 4, and the first section of the second guide plate group 4 overlaps with the end of the first guide plate group 3 by 15% to 25%. The pitch of the second spiral guide plate of the second guide plate group 4 is greater than the pitch of the first spiral guide plate, which is used to gradually attenuate the rotational momentum of the fluid and realize the turbulent transition from spiral flow to horizontal flow.

[0039] Based on the bend centerline of the first arc segment 102 and the second arc segment 104, the spiral inclination angle β of the first spiral guide plate is 10° to 30°, D1 is the diameter of the straight section, and the height h1 of the first spiral guide plate is 0.1D1 to 0.2D1. The leading edge curvature radius R1 is 0.1D1 to 0.15D1, and the trailing edge curvature radius R2 is 0.05D1 to 0.1D1. These features are used to guide the fluid to flow along the spiral trajectory, break up large-scale eddies, and convert turbulent kinetic energy into laminar kinetic energy.

[0040] Working principle: During use, the two ends of the U-shaped connector tube 1 are connected to the inlet pipe and the outlet pipe respectively. Blood enters the U-shaped connector tube 1 and forms a spiral flow through the spiral guide groove 2 inside the U-shaped connector tube 1 to flush the first arc section 102. At the same time, the diameters of the two ends of the first arc section 102 are the same as those of the straight section, and the diameters increase inwards to balance the difference in flow velocity and pressure gradient between the inside and outside of the bend, thus suppressing the generation of turbulence. Meanwhile, the spiral guide plate of the first guide plate group 3 is used to guide the fluid to flow along the spiral trajectory, break up large-scale eddies and convert turbulent kinetic energy into laminar kinetic energy. Based on the dense characteristics on the outside, high-speed turbulence is suppressed, and the sparse characteristics on the inside are used to guide the low-speed flow to homogenize.

[0041] After the fluid passes through the middle straight section 103 and the second arc section 104, it enters the outlet straight section 105. The fluid is guided to the second guide plate group 4 by the first spiral guide plate in the second arc section 104. The pitch of the second spiral guide plate in the second guide plate group 4 is greater than that of the first spiral guide plate. This is used to gradually attenuate the rotational momentum of the fluid and realize the turbulent transition from spiral flow to horizontal flow. Then it is discharged.

[0042] Example 2:

[0043] Basically the same as in Example 1, but further: referring to Figures 1-6 A U-shaped connector device for dead space-free hemodialysis, wherein the pitch of the spiral guide groove 2 gradually increases along the fluid direction, thereby achieving adaptive attenuation of the spiral motion intensity along the flow direction. Through the gradual smoothing of the spiral guide groove 2 and the second guide plate group 4, the fluid is guided to achieve adaptive attenuation of the spiral motion intensity along the flow direction, thereby achieving a turbulent transition from spiral flow to horizontal flow.

[0044] Working principle: During use, the two ends of the U-shaped connector tube 1 are connected to the inlet pipe and the outlet pipe respectively. Blood enters the U-shaped connector tube 1 and forms a spiral flow through the spiral guide groove 2 inside the U-shaped connector tube 1 to flush the first arc section 102. At the same time, the diameters of the two ends of the first arc section 102 are the same as those of the straight section, and the diameters increase inwards to balance the difference in flow velocity and pressure gradient between the inside and outside of the bend, thus suppressing the generation of turbulence. Meanwhile, the spiral guide plate of the first guide plate group 3 is used to guide the fluid to flow along the spiral trajectory, break up large-scale eddies and convert turbulent kinetic energy into laminar kinetic energy. Based on the dense characteristics on the outside, high-speed turbulence is suppressed, and the sparse characteristics on the inside are used to guide the low-speed flow to homogenize.

[0045] After the fluid passes through the middle straight section 103 and the second arc section 104, it enters the outlet straight section 105. The fluid is guided to the second guide plate group 4 by the first spiral guide plate in the second arc section 104. The pitch of the second spiral guide plate in the second guide plate group 4 is greater than that of the first spiral guide plate. This is used to gradually attenuate the rotational momentum of the fluid and realize the turbulent transition from spiral flow to horizontal flow. Then it is discharged.

[0046] Example 3:

[0047] Basically the same as Example 2, but further: referring to Figures 1-6 A U-shaped connector device for dead space-free hemodialysis, wherein a superhydrophilic silica layer is provided on the inner wall of the straight section 105 of the outlet, with a contact angle ≤10° and a thickness of 50-100nm, for inhibiting protein adsorption;

[0048] The superhydrophilic silica layer is doped with 0.1–0.3 wt% silver nanoparticles with a particle size ≤50 nm, which are used to inhibit biofilm formation.

[0049] The inner wall of the spiral guide channel 2 is covered with a high heparin loading layer with a heparin density ≥1.5μg / cm2, providing long-lasting anticoagulation;

[0050] The spiral guide plate of the second guide plate group 4 is covered with a titanium nitride wear-resistant layer with a hardness ≥2000HV, which extends the coating life.

[0051] The U-shaped substrate of the U-shaped connector tube 1 is made of transparent medical-grade polycarbonate or polyetheretherketone, with a light transmittance of ≥80%.

[0052] Working principle: During use, the two ends of the U-shaped connector tube 1 are connected to the inlet pipe and the outlet pipe respectively. Blood enters the U-shaped connector tube 1 and forms a spiral flow through the spiral guide groove 2 inside the U-shaped connector tube 1 to flush the first arc section 102. At the same time, the diameters of the two ends of the first arc section 102 are the same as those of the straight section, and the diameters increase inwards to balance the difference in flow velocity and pressure gradient between the inside and outside of the bend, thus suppressing the generation of turbulence. Meanwhile, the spiral guide plate of the first guide plate group 3 is used to guide the fluid to flow along the spiral trajectory, break up large-scale eddies and convert turbulent kinetic energy into laminar kinetic energy. Based on the dense characteristics on the outside, high-speed turbulence is suppressed, and the sparse characteristics on the inside are used to guide the low-speed flow to homogenize.

[0053] After the fluid passes through the intermediate straight section 103 and the second arc section 104, it enters the outlet straight section 105. The fluid is guided to the second guide plate group 4 by the spiral guide plate 1 in the second arc section 104. The spiral guide plate 2 in the second guide plate group 4 has a larger pitch than the spiral guide plate 1, which is used to gradually attenuate the rotational momentum of the fluid and realize the turbulent transition from spiral flow to horizontal flow before being discharged.

Claims

1. A U-shaped connector device for dead space-free hemodialysis, comprising a U-shaped connector tube (1), wherein the U-shaped connector tube (1) comprises three straight sections and two arc-shaped sections at two corners, namely an inlet straight section (101), a first arc-shaped section (102), a middle straight section (103), a second arc-shaped section (104), and an outlet straight section (105), characterized in that: Also includes: A continuous spiral guide groove (2) is provided on the inner wall from the straight section (101) at the inlet to the second arc section (104), which forces the fluid to generate a spiral motion to flush the inner wall and eliminate dead space; The first guide plate group (3) set in the first arc segment (102) and the second arc segment (104) is spiral-shaped to break up large-scale eddies and maintain spiral flow. The first guide plate group (3) includes multiple spiral guide plates, which are distributed in a ring inside the first arc segment (102) and the second arc segment (104). The arrangement density increases from the inside to the outside of the arc segment to guide the fluid to flow along the spiral trajectory, break up large-scale eddies and convert turbulent kinetic energy into laminar kinetic energy. The radii of curvature of the first arc segment (102) and the second arc segment (104) increase from both ends toward the center of the arc section, balancing the pressure distribution in the curve area and suppressing turbulence generation.

2. The U-shaped connector device for dead space-free hemodialysis according to claim 1, characterized in that, The pitch of the spiral guide groove (2) gradually increases along the fluid direction, so as to realize the adaptive attenuation of the spiral motion intensity along the flow direction.

3. The U-shaped connector device for dead space-free hemodialysis according to claim 1, characterized in that, The mid-section radius of curvature of the first arc segment (102) and the second arc segment (104) is 1.5 to 2 times the radius of curvature of the two ends, satisfying R2 / R1 = 1.5 to 2.0, where R1 is the radius of curvature of the two ends and R2 is the radius of curvature of the center.

4. The U-shaped connector device for dead space-free hemodialysis according to claim 1, characterized in that, The inner wall of the straight section (105) at the outlet is provided with a second guide plate group (4), and the first section of the second guide plate group (4) overlaps with the end of the first guide plate group (3) by 15% to 25%. The pitch of the spiral guide plate of the second guide plate group (4) is greater than the pitch of the spiral guide plate, which is used to gradually attenuate the rotational momentum of the fluid and realize the turbulent transition from spiral flow to horizontal flow.

5. The U-shaped connector device for dead space-free hemodialysis according to claim 1, characterized in that, Based on the curve centerline of the first arc segment (102) and the second arc segment (104), the spiral angle β of the first spiral guide plate is 10° to 30°, D1 is the diameter of the straight section, and the height h1 of the first spiral guide plate is 0.1D1 to 0.2D1.

6. The U-shaped connector device for dead space-free hemodialysis according to claim 1, characterized in that, The inner wall of the straight section (105) at the outlet is provided with a superhydrophilic silica layer with a contact angle ≤10° and a thickness of 50~100nm.

7. A U-shaped connector device for dead space-free hemodialysis according to claim 6, characterized in that, The superhydrophilic silica layer is doped with 0.1 to 0.3 wt% of silver nanoparticles with a particle size ≤ 50 nm, which are used to inhibit biofilm formation.

8. The U-shaped connector device for dead space-free hemodialysis according to claim 1, characterized in that, The inner wall of the spiral guide channel (2) is covered with a high heparin loading layer, with a heparin density ≥1.5μg / cm³. 2 .

9. A U-shaped connector device for dead space-free hemodialysis according to claim 4, characterized in that, The spiral guide plate of the second guide plate group (4) is covered with a titanium nitride wear-resistant layer with a hardness ≥2000HV.

10. A U-shaped connector device for dead space-free hemodialysis according to claim 9, characterized in that, The U-shaped substrate of the U-shaped connector tube (1) is made of transparent medical-grade polycarbonate or polyether ether ketone with a light transmittance of ≥80%.

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