Patent ID: 7997150

Claim:
A meter assembly for the accurate and reliable metering of LPG and other petroleum-based fluids without posing a risk of leakage around, or excessive degradation of, a shaft seal, comprising: a chamber having a respective cover and base configured for collectively forming a sealed measuring chamber, and having at least one fluid inlet and at least one fluid outlet but no other openings into the chamber a rotary measuring element positioned within said chamber for producing a rotary motion that is related to the rate of flow past the element an internal magnetic drive assembly positioned within said chamber, and including a shaft coupling between said rotary measuring element, and an internal magnetic disc; a first cylindrical depression formed by said cover for receiving and locating said internal magnetic disc at a predetermined gap from said cover; an external magnetic drive assembly within said cover but positioned outside said chamber, and including an external magnetic disc; a second cylindrical depression formed by said cover for receiving and locating said external magnetic disc at a predetermined gap from said cover; wherein said first cylindrical depression and said second cylindrical depression are separated by a portion of said cover having a thickness; and whereby a predetermined flux gap is formed between said internal and external magnetic discs so that interacting flux lines between said discs form a fixed mechanical relationship between said discs.