FROST-PROOF DRIVE SHAFT FOR WATER METER

• Main Authors: SWINSON, THIERRY, BRUNSON, CHARLES P., IV
• Format: Patent
• Language: English; French
• Published: 03.12.1993
• Edition: 5
• Subjects: MEASURING; MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUIDLEVEL; METERING BY VOLUME; PHYSICS; TESTING

FROST-PROOF DRIVE SHAFT FOR WATER METER An improved drive shaft for a positive displacement type water meter includes a flexible spring arm formed on one end of the shaft for engaging the drive spindle of a nutating disk measuring element disposed within a water meter. The other end of the drive shaft is connected to a magnetic drive which, in turn, is magnetically coupled to a conventional mechanical register. Under normal conditions, the nutating disk measuring element and drive spindle oscillate in the water meter at a rate proportional to water meter flow. The drive spindle engages the spring arm of the drive shaft causing the drive shaft and magnet to rotate. The magnet is coupled through the water meter casing to a second magnet in the register. Rotation of the second magnet is used to drive the mechanical register to register water consumption. In the event the first magnet within the meter casing becomes frozen to the casing because of external freezing conditions, the drive spindle will snap past the flexible spring arm. This prevents damage to the drive shaft and first magnet which would otherwise occur with conventional drive shaft arrangements.