# Patent

## Title
Apparatus for disinfection of hydrophilic contact lenses

## Abstract

While the methods and forms of heating element and fitting assembly herein described constitute preferred embodiments of the invention, it is to be understood that the invention is not limited to these precise methods and forms of assembly, and that changes may be made therein without departing from the scope and spirit of the invention.

## Background
## Claims

1. In an electrical heating element assembly for mounting within spaced openings of a liquid heating vessel, and including an elongated tubular sheath having opposite end portions, and elongated electrical resistance element positioned within the sheath with a thermally conductive insulation material, and terminal members extending from end portions of the resistance element through the corresponding end portions of the sheath, the improvement comprising a pair of tubular sheet metal fittings each having a flange portion projecting outwardly from a tubular wall portion, said tubular wall portion of each said fitting having a helical convoluted thread portion with a corrugated wall configuration in axial cross-section, each said fitting having axially spaced first and second annular wall portions engaging said sheath at axially spaced locations, and a bonding and sealant material confined within the space defined between said tubular wall portion of each said fitting and said sheath and between said axially spaced first and second corresponding annular wall portions.

2. A heating element assembly as defined in claim 1 wherein said first annular wall portion of each said fitting comprises an inwardly projecting annular hub portion disposed adjacent said flange portion.

3. A heating element assembly as defined in claim 1 wherein said second annular wall portion of each said fitting comprises a generally cylindrical outer end portion of said fitting.

4. A heating element assembly as defined in claim 1 wherein said thread portion of each said fitting extends between the corresponding said first and second annular wall portions.

5. In an electrical heating element assembly for mounting within an opening of a liquid heating vessel, and including an elongated tubular sheath having an end portion and an elongated electrical resistance element positioned within the sheath with a thermally conductive insulation material, the improvement comprising a tubular sheet metal fitting having a flange portion and a tubular wall portion, said tubular wall portion of said fitting having a helical convoluted thread portion with a corrugated wall configuration in axial cross-section, said fitting having axially spaced first and second annular wall portions engaging said sheath at axially spaced locations, and a bonding and sealant material confined within the space defined between said tubular wall portion of said fitting and said sheath and between said axially spaced first and second annular wall portions.

6. A heating element assembly as defined in claim 5 wherein said first annular wall portion comprises an inwardly projecting annular hub portion disposed adjacent said flange portion.

7. A heating element assembly as defined in claim 5 wherein said second annular wall portion comprises a generally cylindrical outer end portion of said fitting.

8. A heating element assembly as defined in claim 5 wherein said thread portion extends between said first and second annular wall portions.