A high pressure contrast piston

Abstract

The utility model provides a kind of high-pressure contrast piston, adopt nested composite structure design, including rubber shell (1) and plastic inner shell (2), wherein plastic inner shell (2) middle part is equipped with cavity (3), rubber shell (1) end is conical surface (4) and is circumferentially arranged stepped seal ring (5), plastic inner shell (2) is radially arranged radial reinforcing rib (6) and the limit groove (7) of rubber shell is embedded. Form double clamping structure by the flanging (8) of rubber shell bottom cladding fixed, combined with the occlusion design of reinforcing rib transverse gap (9) and rubber shell reinforcing rib (10), construct rigid-flexible composite support system. Improve compressive strength to prevent piston cracking, deformation and other problems during injection process.

Description

Technical Field

[0001] This utility model relates to the field of medical device technology, specifically to a high-pressure contrast piston. Background Technology

[0002] High-pressure medical injectors are key components used in medical imaging examinations. The injector contains a plunger, with a piston located at one end of the syringe barrel. The other end is mechanically or electrically driven to precisely control the injection speed, dosage, and pressure of the contrast agent, ensuring that the contrast agent reaches the target blood vessel or organ uniformly within a short time. The stability of the piston directly affects the imaging quality of medical images such as CT (computed tomography). Existing high-pressure contrast pistons, such as CN214343738U, use traditional piston structures and shapes, with only variations in size and dimensions. Due to the high injection pressure, the piston is prone to cracking, fissures, or even breakage and deformation during injection, leading to injection failure.

[0003] The novel high-pressure angiography piston provided by utility model patent CN219743560U strengthens the piston's strength through the setting of reinforcing ribs and curved surface structure. However, the curved surface of this structure has local low-pressure areas, which may generate cavitation and cause blurred vascular imaging. Utility Model Content

[0004] The purpose of this invention is to overcome the shortcomings mentioned in the background art and provide a high-pressure contrast piston with higher strength and greater practicality.

[0005] To achieve the above objectives, the technical solution provided by this utility model is as follows: a high-pressure contrast piston, comprising a nested rubber outer shell and a plastic inner shell, wherein the plastic inner shell has a cavity in the middle, the end face of the rubber outer shell is a conical surface, a sealing ring is provided on the outer circumferential side, the plastic inner shell is provided with a reinforcing rib in the radial direction, and a limiting groove adapted to the reinforcing rib is provided inside the rubber outer shell, wherein the bottom of the rubber outer shell covers the bottom surface of the plastic inner shell and forms a flange to snap onto the plastic inner shell.

[0006] The rubber outer shell provides a flexible seal, while the plastic inner shell provides rigid support, and the cavity is used to connect the syringe push rod.

[0007] Furthermore, the reinforcing ribs are evenly distributed around the circumference and arranged radially in 4-8 strips.

[0008] Furthermore, at least two sealing rings are provided, extending from the end face of the rubber shell towards the cavity, with the outer diameter of the multiple sealing rings decreasing in a stepped manner. The stepped sealing rings dissipate pressure energy at each stage, preventing overall leakage due to single-stage seal failure.

[0009] Furthermore, the reinforcing rib has at least one set of notches arranged laterally, and the inner side of the rubber shell has reinforcing ribs adapted to the notches arranged laterally.

[0010] Furthermore, the bottom surface of the rubber shell is provided with anti-stick protrusions evenly distributed around its circumference.

[0011] Furthermore, the flange of the rubber outer shell is chamfered. The chamfer is used to facilitate the insertion of the syringe push rod into it. For illustration, the plastic inner shell can be integrally molded with the push rod, allowing the push rod to be inserted into the rubber outer shell, thus avoiding any connection obstruction caused by the rigidity of the plastic inner shell.

[0012] Furthermore, at the connection between the sealing ring and the rubber shell, a stress relief groove is provided on the side of the sealing ring near the flange. This stress relief groove at the root of the sealing ring allows for a slight floating motion of the sealing ring during piston movement, extending its fatigue life.

[0013] Furthermore, the sealing ring, reinforcing ribs, and flanges are integrally connected to the rubber shell.

[0014] The advantages and beneficial effects of this invention are as follows: A composite support system is formed through the nested design of a rubber outer shell and a plastic inner shell, utilizing the elastic deformation capability of rubber and the rigid support characteristics of plastic to enhance the overall compressive strength of the piston. The cooperation between the reinforcing ribs and the limiting groove, and the engagement between the notch and the reinforcing ribs, further improves the strength of the high-pressure contrast piston. This solves the technical defects of existing pistons, such as easy breakage and blurred imaging due to cavitation, ensuring the safe and accurate injection of high-pressure contrast agents. Attached Figure Description

[0015] Figure 1 This is a cross-sectional structural diagram of the piston of this utility model; Figure 2 This is a schematic diagram of the bottom structure of the piston of this utility model; Reference numerals: 1-Rubber outer shell, 2-Plastic inner shell, 3-Cavity, 4-Conical surface, 5-Sealing ring, 6-Reinforcing rib, 7-Limiting groove, 8-Flanged edge, 9-Notch, 10-Reinforcing rib, 11-Anti-stick protrusion, 12-Chamfer, 13-Stress relief groove. Detailed Implementation

[0016] The specific embodiments of this utility model will be further described below with reference to the accompanying drawings and examples. The following examples are only used to more clearly illustrate the technical solution of this utility model and should not be construed as limiting the scope of protection of this utility model.

[0017] Example 1 A high-pressure contrast piston, such as Figure 1-2As shown: This piston consists of a nested rubber outer shell 1 and a plastic inner shell 2. The rubber outer shell 1 is made of silicone, and the plastic inner shell 2 is made of polycarbonate. A cavity 3 is machined in the middle of the plastic inner shell 2, and six reinforcing ribs 6 are evenly distributed radially on its outer wall. The front end of the rubber outer shell 1 has a conical surface 4, and two stepped sealing rings 5 ​​with outer diameters of Φ28mm and Φ26mm respectively are circumferentially arranged on its outer side. The inner surface of these rings has a limiting groove 7 that precisely matches the reinforcing ribs 6. The bottom of the rubber outer shell 1 is formed by injection molding to create a 3mm flange 8, which wraps around the bottom surface of the plastic inner shell 2. The sealing rings 5, flange 8, and outer shell body are manufactured using an integral molding process. This piston can withstand pressures exceeding 400kPa without cracking or significant deformation.

[0018] Example 2 A high-pressure contrast-enhancing piston differs from Embodiment 1 in that the rubber outer shell 1 is provided with three stepped sealing rings 5, with outer diameters of Φ30mm, Φ28mm, and Φ26mm respectively, forming a pressure gradient seal. The bottom surface of the plastic inner shell 2 is machined with four anti-stick ridges 11, with a ridge height of 0.3mm, and the edge of the flange 8 is machined with a 45° chamfer 12 with a chamfer width of 1.2mm.

[0019] Example 3 A high-pressure contrast piston differs from that of Example 2 in that the reinforcing rib 6 has two sets of notches 9 in the middle, each measuring 2mm × 1mm, corresponding to reinforcing ribs 10 molded on the inner side of the rubber outer shell 1, which interlock and lock together. An annular stress relief groove 13 with a depth of 0.2mm is machined at the root of the sealing ring 5.

[0020] The working principle of this invention lies in the nested combination of a rubber outer shell and a plastic inner shell. The rubber material provides elastic sealing and cushioning properties, while the plastic inner shell provides rigid support, forming a composite structure that is "flexible on the outside and rigid on the inside." During high-pressure injection, the pressure is evenly transmitted to the plastic inner shell through the rubber outer shell. The rigid inner shell disperses stress through reinforcing ribs, preventing localized stress concentration that could lead to cracking. The radial reinforcing ribs of the plastic inner shell are embedded in the limiting grooves of the rubber outer shell, forming longitudinal anti-deformation constraints. The transverse notches of the reinforcing ribs interlock laterally with the reinforcing ribs of the rubber outer shell, constructing a multi-dimensional shear force resistance system. The stepped sealing rings, arranged along the end face of the rubber outer shell, have progressively decreasing outer diameters, forming a pressure gradient sealing layer that gradually dissipates pressure energy. A stress relief groove is provided at the root of the sealing ring, allowing for slight deformation of the sealing ring, alleviating stress concentration, and extending fatigue life.

[0021] The above description is only a preferred embodiment of the present utility model. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present utility model, and these improvements and modifications should also be considered within the protection scope of the present utility model.

Claims

1. A high-pressure contrast-enhancing piston, characterized in that: It includes a nested rubber shell (1) and a plastic inner shell (2). The plastic inner shell (2) has a cavity (3) in the middle. The end face of the rubber shell (1) is a conical surface (4). A sealing ring (5) is provided on the outer circumferential side. The plastic inner shell (2) is provided with a reinforcing rib (6) in the radial direction. The rubber shell (1) is provided with a limiting groove (7) that matches the reinforcing rib (6). The bottom of the rubber shell (1) covers the bottom surface of the plastic inner shell (2) and forms a flange (8) to snap the plastic inner shell (2).

2. The high-pressure contrast-enhancing piston according to claim 1, characterized in that, The reinforcing ribs (6) are evenly distributed around the circumference and arranged radially in 4-8 strips.

3. The high-pressure contrast-enhancing piston according to claim 1, characterized in that, The sealing ring (5) is provided in at least two directions along the end face of the rubber shell (1) towards the cavity (3), and the outer diameter of the multiple sealing rings (5) decreases in a stepped manner.

4. The high-pressure contrast-enhancing piston according to claim 1, characterized in that, The reinforcing rib (6) is provided with at least one set of notches (9) in the transverse direction, and the inner side of the rubber shell (1) is provided with reinforcing ribs (10) adapted to the notches (9).

5. The high-pressure contrast-enhancing piston according to claim 1, characterized in that, The bottom surface of the rubber shell (1) is provided with anti-stick protrusions (11) evenly distributed around the circumference.

6. The high-pressure contrast piston according to claim 1, characterized in that, The flange (8) of the rubber shell (1) is provided with a chamfer (12).

7. The high-pressure contrast-enhancing piston according to claim 3, characterized in that, At the connection between the sealing ring (5) and the rubber shell (1), a stress relief groove (13) is provided on the side of the sealing ring (5) near the flange (8).

8. The high-pressure contrast piston according to any one of claims 1-7, characterized in that, The sealing ring (5), reinforcing rib (10), and flange (8) are integrally connected with the rubber shell (1).

Images