Plunger pump for hemodialysis with multi-stage sealing structure

Abstract

The utility model discloses a kind of plunger pumps with multistage sealing structure for hemodialysis, sealing structure includes the inner core force layer for supporting in inside, the outer functional layer of cladding in the outer periphery of inner core force layer, the surface composite functional layer of the outer periphery of outer functional layer, surface composite functional layer annular array has groove and fills solidification layer for adsorbing moisture in groove. Ensure the durability and stability of entire sealing performance, inhibit the formation of thrombus, promote surface lubrication and anti-adhesion performance.

Description

Technical Field

[0001] This utility model relates to the field of medical device technology, specifically to a plunger pump for hemodialysis with a multi-stage sealing structure. Background Technology

[0002] A piston pump is a positive displacement pump whose core working principle is to achieve the intake and discharge of liquid in a hemodialysis machine through the periodic change of a sealed volume. It is characterized by high output pressure, precise and controllable flow rate, and high efficiency.

[0003] During operation, the sealing performance of a plunger pump directly affects its efficiency. Currently, existing plunger pumps only use O-rings for sealing. Over time, this wear can lead to gaps between the pump housing and the plunger sleeve, causing liquid leakage, reducing the pump's sealing performance, and impacting the plunger's lifespan.

[0004] Therefore, this application is submitted. Utility Model Content

[0005] The purpose of this invention is to provide a plunger pump for hemodialysis with a multi-stage sealing structure, which improves the sealing reliability of the sealing structure, extends service life, and reduces the frequency of replacement.

[0006] To solve the above-mentioned technical problems, the present invention adopts the following solution: A plunger pump for hemodialysis with a multi-stage sealing structure includes an inner core support layer located inside for support, an outer functional layer covering the outer periphery of the inner core support layer, and a surface composite functional layer on the outer periphery of the outer functional layer. The surface composite functional layer has grooves arranged in a ring array and the grooves are filled with a solidified layer for adsorbing moisture.

[0007] Furthermore, the pattern of the groove is either rectangular or hemispherical.

[0008] Furthermore, the depth of the trench is 20μm to 40μm and the width is 30μm to 80μm.

[0009] Furthermore, the cured layer is a phospholipid polymer filler or a polyvinylpyrrolidone hydrogel filler.

[0010] Furthermore, the cross-section of the inner core load-bearing layer is an annular structure, and its cross-sectional diameter is 60% to 70% of the diameter of the sealing structure.

[0011] Furthermore, the thickness of the outer functional layer is 0.4mm to 0.7mm.

[0012] Furthermore, the inner core load-bearing layer is made of wear-resistant polymer material; the outer functional layer is made of medical-grade silicone rubber.

[0013] Furthermore, the wear-resistant polymer material is made of fluororubber or polyetheretherketone.

[0014] Furthermore, the medical-grade silicone rubber material is made of liquid silicone rubber.

[0015] Furthermore, the overall shape of the sealing structure is an O-ring or a lip seal.

[0016] The beneficial effects of this utility model are: This invention features a sealing structure consisting of an inner core load-bearing layer, an outer functional layer, and a surface composite functional layer, forming a three-layer composite mechanism. Grooves filled with a cured layer are formed on the outer periphery of the surface composite layer. The inner core load-bearing layer primarily serves as the skeleton of the sealing structure, providing essential mechanical strength, elastic recovery, and compression resistance, ensuring the durability and stability of the overall sealing performance. The silicone matrix of the outer functional layer and the cured layer within the grooves of the surface composite functional layer together create a surface with extremely high bioinertness, making it difficult for proteins to adhere, thus inhibiting thrombus formation and improving surface lubrication and anti-adhesion properties. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of this utility model; Figure 2 This is a cross-sectional view of the sealing structure of this utility model; Figure 3 This is a cross-sectional schematic diagram of the sealing structure of this utility model.

[0018] Reference numerals: 1-plunger rod, 2-plunger sleeve, 3-plunger pump housing, 4-sealing structure, 40-inner core load-bearing layer, 41-outer functional layer, 42-surface composite functional layer, 420-groove, 421-curing layer. Detailed Implementation

[0019] The present invention will be further described in detail below with reference to the embodiments and accompanying drawings, but the embodiments of the present invention are not limited thereto.

[0020] In the description of this utility model, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "longitudinal", "lateral", "horizontal", "inner", "outer", "front", "rear", "top", "bottom", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the utility model product is in use. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0021] In the description of this utility model, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set up," "have," "install," "connect," and "connect" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0022] Example 1 Embodiment 1 of this utility model is a plunger pump for hemodialysis with a multi-stage sealing structure. The sealing structure 4 includes an inner core support layer 40 located inside for support, an outer functional layer 41 covering the outer periphery of the inner core support layer 40, and a surface composite functional layer 42 on the outer periphery of the outer functional layer 41. The surface composite functional layer 42 has a plurality of grooves 420 arranged in a ring array and the grooves 420 are filled with a curing layer 421 for absorbing moisture.

[0023] Reference Figure 1 and Figure 2 This invention primarily improves sealing performance by incorporating a multi-stage sealing structure 4 at the end of the plunger rod 1 near the plunger pump rotor, forming a three-layer composite structure. Grooves 420 are provided on the surface of the composite functional layer 42, enhancing sealing performance. A curing layer 421 within the grooves 420 fully utilizes hydrophilic properties to adsorb moisture, preventing further entry of moisture into the gap between the plunger sleeve 2 and the plunger shell, thus further improving sealing performance. Simultaneously, the inner core load-bearing layer 40 serves as the skeleton of the sealing structure 4, providing essential mechanical strength, elastic recovery, and compression resistance, ensuring the durability and stability of the overall sealing performance.

[0024] Secondly, the outer functional layer 41 acts as a safety isolation layer, completely separating the inner core support layer 40 from the blood. Simultaneously, the surface composite functional layer 42 on its surface, filled with a curing layer 421, can absorb a large amount of moisture, forming a highly hydrated and smooth surface that prevents blood clotting, thus providing anticoagulant function and improving safety. The smooth surface also reduces friction, minimizes wear, and extends service life. The outer functional layer 41 can also provide wear warnings. By changing its color (e.g., to a light color) to a dark color (e.g., black) for the inner core support layer 40, the outer functional layer 41 will become visible when it wears down to a certain extent due to prolonged use. This provides a warning signal to maintenance personnel, indicating that the sealing structure 4 is nearing the end of its service life and needs to be replaced during the next maintenance, thereby preventing malfunctions caused by sudden failure of the sealing structure 4.

[0025] In some preferred embodiments, the pattern of the groove 420 is either rectangular or hemispherical. (See reference...) Figure 3 The diagram shows a cross-sectional view of the entire sealing structure 4. Multiple grooves 420 are provided on the surface of the surface composite functional layer 42. The depth of each groove 420 is 20μm to 40μm, and the width is 30μm to 80μm. The specific shape and size of the grooves 420 can be set according to actual needs and will not be elaborated here. The key feature is that a curing layer 421 for moisture adsorption is provided inside the grooves 420. The grooves 420 on the surface composite functional layer 42 can be processed by laser etching, which is a prior art technique.

[0026] It should be noted that the cured layer 421 is a phospholipid polymer filler or a polyvinylpyrrolidone hydrogel filler. First, an aqueous solution is filled into the trench 420, and then this aqueous solution is cured using existing curing methods to form a cured layer 421 within the trench 420, thus ensuring that the cured layer 421 is firmly attached to the trench 420. The cured hydrogel material can absorb a large amount of water, forming a stable hydrated lubricating layer on the surface of the sealing structure 4, significantly reducing the coefficient of friction and decreasing the shear force on the blood components.

[0027] In some preferred embodiments, the inner core load-bearing layer 40 has an annular cross-section, with a diameter of 60% to 70% of the diameter of the sealing structure 4. The inner core load-bearing layer 40 serves as the main framework of the sealing structure 4, occupying a large portion of the entire structure and improving its overall mechanical properties. Its dimensions can be set within this range according to actual needs, and will not be elaborated upon here. The thickness of the outer functional layer 41 is 0.4 mm to 0.7 mm.

[0028] In some preferred embodiments, the inner core load-bearing layer 40 is made of a wear-resistant polymer material; the wear-resistant polymer material is made of fluororubber or polyetheretherketone. The outer functional layer 41 is made of medical-grade silicone rubber. The medical-grade silicone rubber material is made of liquid silicone rubber.

[0029] Fluororubber (FKM) or polyetheretherketone (PEEK) possesses high strength and high wear resistance, providing the main mechanical strength for the inner core load-bearing layer 40 and ensuring the durability and stability of the seal. The surface functional layer is co-molded onto the outer surface of the inner core load-bearing layer 40, forming a strong chemically bonded interface. The excellent bioinertness of silicone ensures the safety of the base material, eliminating the risk of trace leaching that may exist with fluororubber. Simultaneously, together with the cured layer 421 within the grooves 420 of the surface composite functional layer 42, it constitutes a surface with extremely strong bioinertness, making it difficult for proteins to adhere, fundamentally inhibiting thrombus formation and improving surface lubrication and anti-adhesion properties.

[0030] In some preferred embodiments, the overall shape of the sealing structure 4 is an O-ring or a lip seal. The overall sealing mechanism in this invention is an O-ring, see reference... Figure 3 The specific shapes can be set according to the actual situation, and will not be listed one by one here.

[0031] The working principle of this utility model is as follows: In use, the sealing structure 4 has a three-layer composite structure, and grooves 420 are provided on the surface of the surface composite functional layer 42 to jointly improve the sealing performance. The curing layer 421 set within the grooves 420 fully utilizes the hydrophilic properties to adsorb moisture, preventing further moisture from entering the gap between the plunger sleeve 2 and the plunger shell, thus improving the sealing performance. Simultaneously, the inner core load-bearing layer 40 mainly serves as the skeleton of the sealing structure 4, providing the main mechanical strength, elastic recovery force, and compression resistance, ensuring the durability and stability of the overall sealing performance. The silicone matrix of the outer functional layer 41 and the curing layer 421 within the grooves 420 of the surface composite functional layer 42 together form a surface with extremely strong biological inertness, making it difficult for proteins to adhere, inhibiting thrombus formation, and improving surface lubrication and anti-adhesion properties.

[0032] The above description is merely a preferred embodiment of the present utility model and is not intended to limit the present utility model in any way. Any simple modifications, equivalent substitutions, and improvements made to the above embodiments based on the technical essence of the present utility model and within the spirit and principles of the present utility model shall still fall within the protection scope of the present utility model.

Claims

1. A plunger pump for hemodialysis with a multi-stage sealing structure, characterized in that, The sealing structure (4) includes an inner core support layer (40) located inside for support, an outer functional layer (41) covering the outer periphery of the inner core support layer (40), and a surface composite functional layer (42) on the outer periphery of the outer functional layer (41). The surface composite functional layer (42) has grooves (420) arranged in annular array and is filled with a curing layer (421) for absorbing moisture.

2. A plunger pump for hemodialysis with a multi-stage sealing structure according to claim 1, characterized in that, The pattern of the groove (420) is either rectangular or hemispherical.

3. A plunger pump for hemodialysis with a multi-stage sealing structure according to claim 1, characterized in that, The trench (420) has a depth of 20μm ~ 40μm and a width of 30μm ~ 80μm.

4. A plunger pump for hemodialysis with a multi-stage sealing structure according to claim 1, characterized in that, The cured layer (421) is a phospholipid polymer filler or a polyvinylpyrrolidone hydrogel filler.

5. A plunger pump for hemodialysis with a multi-stage sealing structure according to claim 1, characterized in that, The cross-section of the inner core load-bearing layer (40) is an annular structure, and its cross-sectional diameter is 60% to 70% of the diameter of the sealing structure (4).

6. A plunger pump for hemodialysis with a multi-stage sealing structure according to claim 1, characterized in that, The thickness of the external functional layer (41) is 0.4 mm to 0.7 mm.

7. A plunger pump for hemodialysis with a multi-stage sealing structure according to claim 1, characterized in that, The inner core load-bearing layer (40) is made of wear-resistant polymer material; the outer functional layer (41) is made of medical-grade silicone rubber.

8. A plunger pump for hemodialysis with a multi-stage sealing structure according to claim 7, characterized in that, The wear-resistant polymer material is made of fluororubber or polyetheretherketone.

9. A plunger pump for hemodialysis with a multi-stage sealing structure according to claim 7, characterized in that, The medical-grade silicone rubber material is made of liquid silicone rubber.

10. A plunger pump for hemodialysis with a multi-stage sealing structure according to claim 7, characterized in that, The overall shape of the sealing structure (4) is an O-ring or a lip seal.

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