Ronald E Roy

US Patent:

61351105, Oct 24, 2000

Filed:

Apr 22, 1998

Appl. No.:

9/063897

Inventors:

Ronald R. Roy - Spofford NH

Assignee:

Sims Portex Inc. - Keene NH

International Classification:

A61M 1600

US Classification:

12820715

Abstract:

To ensure that the inner cannula is mated to the outer cannula of a tracheostomy tube, a pressure adjusting device is provided to the collar of the inner cannula so as to apply a biasing force against the tabs that extend from the hub of the outer cannula. The torque force that is required to assemble/disassemble the inner cannula to/from the outer cannula may be adjusted by increasing or decreasing the thickness of the pressure adjusting device which may be in the form of a spring ring which elasticity is adjustable by varying the thickness thereof. Ramps are provided within the collar of the inner cannula to guide the movement of the tabs relative to that of the collar. In addition, stops are provided within the collar for arresting any further movement of the tabs with respect to the collar. Indents are further provided within the collar whereat the tabs can rest. By thus applying a biasing force against the tabs while they rest on the indents, absent a deliberate disassemble torque to the collar, the inner cannula will stay securely fixed to the outer cannula.