7results about How to "Low bending stiffness" patented technology

The invention relates to the technical field of medical instruments, and discloses a micro catheter. Wherein the microcatheter is sequentially provided with a lining tube and a high polymer material layer from inside to outside in the radial direction, a variable-diameter section is arranged at the far end of the microcatheter, a small-diameter section is arranged on one side of the far end of the variable-diameter section, and a large-diameter section is arranged on one side of the near end of the variable-diameter section; the high polymer material layer comprises a first hardness area, a second hardness area and a third hardness area which are sequentially arranged from the far end to the near end, the first hardness area is located on a part of the small-diameter section, the second hardness area is located on the other part of the small-diameter section, the variable-diameter section and a part of the large-diameter section, and the third hardness area is located on the other part of the large-diameter section; the hardness of the first hardness area is smaller than that of the second hardness area, the hardness of the second hardness area is smaller than that of the third hardness area, and smooth transition of different hardness materials of the large-diameter section and the small-diameter section of the microcatheter is achieved; the flexural rigidity of the reducing section is reduced, so that the change value of the flexural rigidity is reduced, the stress concentration is reduced, and the reliability of the microcatheter is improved.

The application provides a micro catheter, comprising a tube body, the tube body comprising an inner layer, an intermediate layer and an outer layer, the intermediate layer comprising a reinforcing area, a body area and a weakening area arranged in sequence along the circumferential direction of the tube body, the bending stiffness of the reinforcing area, the body area and the weakening area decreasing in sequence. Therefore, the bending stiffness of the tube body on the side of the reinforcing area is stronger, so that the micro catheter has better pushing performance and supportability on the side of the reinforcing area, and the kinking caused by the transitional bending of the micro catheter can be avoided. Meanwhile, the bending stiffness of the tube body on the side of the weakening area is smaller, the local flexibility is higher, and the bending performance is better. The body area maintains the basic stiffness and performance of the tube body and forms a smooth transition between the reinforcing area and the weakening area, so that the local stress concentration does not cause the bending failure of the catheter, thereby realizing the passability of the micro catheter in special tortuous blood vessels and the plasticity of the head end.

This application relates to the field of semiconductor technology, specifically to a MEMS piezoelectric loudspeaker and acoustic device, including a substrate and a piezoelectric stack disposed on the substrate; the piezoelectric stack has multiple tangents extending from the geometric center of the piezoelectric stack to the edge of the piezoelectric stack, forming multiple cantilever beams arranged rotationally symmetrically about the geometric center; each cantilever beam has a fixed edge away from the geometric center; at least two of the cantilever beams have trench structures on the substrate, the trench structures being located close to the fixed edge of the cantilever beam. This application can reduce peaks at resonant frequencies and effectively expand the frequency bandwidth, improving overall audio performance; in addition, this application can also reduce diaphragm stiffness, thereby significantly enhancing its low-frequency deformation capability and optimizing the low-frequency sound pressure level curve.

The application belongs to the technical field of additive manufacturing material preparation, and particularly relates to a preparation device and method of high-fiber-content reinforced polyether ether ketone 3D printing wire rod, which comprises: a material source assembly for providing an impregnated tape; a filament splitter in communication with the material source assembly, which divides the wide impregnated tape into multiple narrow strips through a cutter shaft and a circular disc split cutting knife; multiple multi-nozzle step-by-step pultrusion devices corresponding to the narrow strips, which are provided with multiple nozzles with gradually reduced diameters at the discharge end, and are used for heating, guiding, pressurizing, impregnating and cooling the narrow strips; and a wire collecting reel in communication with each pultrusion device. Through the parallel process of "first dividing and then pulling", the application solves the problems of low forming freedom of the wide pre-impregnated tape, large damage and high cost in traditional wire rod preparation, and realizes efficient and low-damage continuous production of high-performance 3D printing wire rod.

The present application provides a kind of anti-perforation gastroscopes and control method, wherein the device comprises: sensing integrated module, be provided at the front end of endoscope insertion tube, for synchronously obtaining the contact pressure data of mirror body circumferential, the microscopic structure image of mucosa tissue and the kinematic data of mirror body;It transmits the original sensing signal in real time to data processing unit through signal transmission bus;Data processing unit is connected with sensing integrated module, for the received multimodal sensing signal is carried out space-time alignment, extracts mucosa deformation feature and generates real-time risk score fusion;Data processing unit outputs the multi-level execution instruction corresponding to risk score;Active intervention module, it includes the physical response mechanism distributed in the front end of mirror body and the mechanical blocking mechanism in handle end;Active intervention module receives the execution instruction through the logic control interface, and drives corresponding mechanism to adjust the physical rigidity of mirror body or operating resistance of advance mirror;The present application can effectively reduce the risk of perforation.

This invention provides a vacuum composite LNG cryogenic pipeline, comprising four functional layers from the inside out: an inner composite pipeline layer, a vacuum layer, an outer composite pipeline layer, and an outer sheath layer. The inner composite pipeline layer consists of an inner spiral wire layer, a sealing layer, a braided layer, another sealing layer, and an outer spiral wire layer, arranged sequentially from the inside out. The vacuum layer is formed by an annular area between the inner and outer composite pipeline layers, supported by an insulating gasket ring, providing vacuum insulation. The outer composite pipeline layer consists of inner and outer spiral wire layers as its innermost and outermost layers, a sealing layer as its second layer, and a braided layer as its third layer. The outer sheath layer comprises an outer sheath. This invention offers superior bending flexibility and low bending stiffness, making it less prone to fatigue damage under external tensile and bending cyclic loads. It also provides excellent insulation, more rational stress transmission in cryogenic pipelines, and a wider range of applications.

This invention provides a method and application for measuring the surface thermal expansion coefficient of a layered two-dimensional material. The method includes: measuring the flexural stiffness δ of the layered two-dimensional material in a direction perpendicular to the plane, and the thermal expansion coefficient α of the chemical bonds in the layered two-dimensional material. bond Substituting into equation (1), we obtain the surface thermal expansion coefficient α of the layered two-dimensional material. s ;α s =2α bond –50 / δ(1). This invention proposes for the first time that the thermal expansion coefficient of a two-dimensional material can be obtained by combining these two testing schemes and converting them. This measurement method has the advantages of simple operation, transferable test data, wide temperature coverage, and stable results.