IMPROVED CATHETER DISTAL END ASSEMBLIES

摘要

The present invention includes improved assemblies for transferring torque from a catheter main body tube (104) to the steering center support member (120) through the buff bond joint assembly. Such improvements include the utilization of a crimp sleeve (290) that is disposed within the butt bond sleeve (274), such that an enhanced mechanical interference is created within the adhesive that is utilized to fill the but bond sleeve. Various crimp sleeve shapes are disclosed. Alternatively, a stiffener member may be fixedly engaged to the steering mechanism, where the stiffener member includes an arm portion that projects into the butt bond sleeve area. The projecting arm portion is bonded into the adhesive that fills the butt bond sleeve. Additional torque enhancing features include radially inwardly project ribs that are formed in the butt bond sleeve, and laterally extending portions of the steering center support member which create enhanced mechanical interference with the adhesive disposed within the butt bond sleeve. The improved steering and control features of the present invention are obtained by locating the attachment point of the steering wires with the center support member a suitable distance proximate to the distal end of the center support member. Additionally, improvements to the shape of the center support member provide enhanced control characteristics. In a preferred embodiment, the steering wire attachment point is located approximately one inch proximal to the distal tip of the device.