主权项 |
1. A control handle for a steerable catheter, comprising:
a housing assembly having a proximal portion and a distal portion and defining a central axis, said proximal portion defining a central bore concentric with said central axis, said central bore including radial step that defines a shoulder concentric about said central axis; a resistance adjusting assembly including a threaded member that is threadably engaged with said housing assembly, said resistance adjusting assembly having a bearing surface that cooperates with said shoulder of said central bore to define a gland that is concentric about said central axis, said gland having a volume that varies with a position of said resistance adjusting assembly; a deformable gasket disposed in said gland; and a piston assembly disposed within said housing assembly, said piston assembly extending distally from said distal portion of said housing assembly, said piston assembly including a glide assembly within said central bore of said proximal portion and having an axial length along said central axis, said glide assembly being positioned so that said gland is radially adjacent said axial length of said glide assembly and in contact with said deformable gasket that causes a friction force on said glide assembly when said piston assembly is translated relative to said housing assembly, said friction force being variable with said volume of said gland. |