A fixed locking structure, medical catheter, and blood pump

Abstract

The invention discloses a fixed locking structure, which comprises an inner cylinder, a chuck and an outer cylinder sleeved outside the catheter; the catheter includes a drive shaft and a sheath located outside the drive shaft; the chuck is a cylindrical elastic body; The distal end of the cylinder forms a first cavity for accommodating the chuck, the proximal end of the inner cylinder is connected to the distal end of the outer cylinder through a connection structure, one end of the chuck abuts against the proximal end of the inner cylinder, and the other end It abuts against the inner wall of the first cavity; both ends of the chuck are provided with a clamping part, and the clamping part is provided with a plurality of notches at equal intervals along the circumferential direction, and the inner cylinder and the outer cylinder are in contact with the clamping part A crimping portion is formed. The present invention is provided with a chuck with clamping parts at both ends, and the inner cylinder and the outer cylinder are provided with crimping parts abutting against the clamping part; the clamping part is provided with a notch along the circumference, so that the sheath tube Outwardly deformed, the deformation of the sheath can be controlled; the clamping part and the crimping part have a circular platform structure, and through the abutment of the circular table surface, radial pressure is applied during axial locking to ensure a fixed locking effect.

Description

technical field [0001] The invention relates to the field of medical devices, in particular to a fixed locking structure, a medical catheter and a blood pump. Background technique [0002] The clinical use of percutaneous catheter pumps is to pump blood from the ventricle, flow through the transvalvular catheter, and enter the artery from the outflow port. This working principle determines that the suction port and the outflow port must be distributed on both sides of the valve. When the product is implanted, under the guidance of DSA (Digital subtraction angiography, digital subtraction angiography), the suction port and the outflow port can be accurately distributed on both sides of the valve. After the product is placed in place, the suture system and the catheter need to be fixedly connected through the locking structure, and then the entire catheter body and the human body should be fixed through the suture system. If the locking between the locking structure and the c...

AI Technical Summary

Problems solved by technology

[0003] The locking structure described in Chinese patent CN109793975A is that when the locking cap and the locking base are tightened, the elastic locking ring 5 is axially squeezed, and radial compression is formed through the principle of volume conservation to achieve the purpose of locking. The method has the following problems: when the locking structure is radially compressed, the radial deformation of the elastic locking ring is difficult to control, and the deformation of the sheath tube 4 of the corresponding catheter is difficult to predict, such as figure 1 shown

This situation will lead to the following problems: 1. The locking force is unstable or the consistency of the locking force is not good; when the elastic locking ring 5 is squeezed axially, the tube wall of the locking ring 5 is deformed, and the deformation cannot be predicted , will cause the contact surfaces of the locking ring 5 and the sheath tube 4 to have different shapes, and when the locking cap and the locking base are screwed into the same displacement, the locking forces generated at different positions on the outer wall of the locking ring 5 are different; 2. When it is tight, it will lead to internal collapse; because in the process of use, the deformation of the tube wall of the locking ring 5 is not controlled, so in order to achieve the required locking force, the local deformation of the wall of the sheath tube 4 will be too large, resulting in abnormalities such as collapse inside the catheter. Expected structural changes; 3. After locking, the minimum inner diameter of the sheath is small; in the clinical use of percutaneous interventional blood pumps, the catheter at least includes the internal mechanical transmission shaft and the external sheath 4, and it is expected that when locked, it remains The size of the inner wall of the sheath tube 4, to ensure the normal operation of the mechanical transmission shaft

Each lobe of the multi-lobe structure of the locking head 9 forms a cantilever structure. To achieve locking at the far end, a greater pressure needs to be applied at the proximal end, resulting in concentrated stress at the proximal end 91 of the locking head, and the stress at the proximal end 91 of the locking head The concentrated part is easy to break and damage, and at the same time, the distal end 92 of the locking head needs to achieve the strength of locking the catheter sheath 4, and the valve-like structure of the distal end 92 of the locking head needs to have a large contraction, resulting in large deformation of the sheath tube 4, making the catheter The inner space is small, so it is not suitable for use in occasions that contain a mechanical transmission shaft inside the catheter

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