Broadbent v Davies

Broadbent and another appealed to the High Court of Australia from a decision of the Commissioner of Patents who had refused to grant a patent for improvements in inferential water meters. The applicants, Broadbent and Parks, sought a patent for a new method of attaching a turbine rotor to a spindle in water meters, as well as for the construction of the turbine itself. The opponent, Edgar Naunton Davies, opposed the grant on the grounds that the applicants' invention was anticipated by his own prior patent and that certain claims lacked subject matter.

The legal issues before the High Court were whether the applicants' proposed method for attaching the turbine rotor to the spindle was novel and possessed sufficient subject matter, and whether the description of the turbine construction was sufficiently clear and distinct. Specifically, the court had to determine if the applicants' method of gripping a thin sheet of soft metal in a groove around a hard metal spindle constituted a new invention compared to the opponent's method of pressing a soft metal turbine onto the end of a hard metal spindle and securing it with a corrugation. The court also considered its power under section 47 of the Patents Act 1903-1909 to impose conditions on the grant of a patent, including the amendment of a specification.

The High Court found that the applicants' method of attaching the turbine rotor was novel and involved invention, distinguishing it from the opponent's method. The court reasoned that the opponent's method involved forming a corrugation in the soft metal disc to grip the spindle, whereas the applicants' method involved expanding a ring of soft metal through a hole in the disc to grip it. This difference in mechanical operation and the resulting pressure lines was considered significant. The court also noted that while the general construction of turbines was known, the specific combination with the new fixing method was inventive. Regarding the fifth claim, the court found it to be ambiguous but capable of being construed to claim the combination of the new fixing method with the known turbine construction.

The High Court allowed the appeal, ordering that a patent be granted to the applicants. This grant was made conditional upon the applicants amending claim 5 of their specification by inserting the word "having" before the words "the internal edge" to clarify its intended meaning. The respondent was ordered to pay the costs of the appeal and the costs incurred before the Commissioner.