04488152 is referenced by 52 patents and cites 7 patents.

A visually and electronically readable motor driven register has a plurality of dependently rotatable, coaxial, incrementally positionable, number wheels which each carry a movable electrode fixed in a predetermined position relative to the numbers on each wheel. Adjacent each movable electrode is inserted a fixed plate which carries a plurality of stationary electrodes, each corresponding to a number on the wheel and disposed circumferentially around a stationary main electrode which is capacitively coupled to the movable electrode. When a number on a wheel is visually readable, the movable electrode will be positioned so as to be capacitively coupled only to the stationary electrode corresponding to the readable number. A microprocessor provides pulses sequentially to the stationary electrodes of each wheel, and checks for a coincident processed output from the main electrode of the first wheel. If there is a processed output indicating capacitive coupling between stationary and movable electrodes, the microprocessor retains the electrode number indicative of the readable number of the first wheel and checks for a coincident processed output from the main electrode of the second wheel. When all the wheels have been read, the first wheel is again checked; if all the wheels have not been able to be read, the microprocessor will activate the motor to move the wheels until they can all be read.

Title
Register position sensing and controlling apparatus
Application Number
6/344701
Publication Number
4488152
Application Date
February 1, 1982
Publication Date
December 11, 1984
Inventor
Michael J Hampton
Agincourt
CA
John D Arnason
Toronto
CA
Agent
Dale Gaudier
Assignee
Schlumberger Canada
CA
IPC
G08C 19/00
G08C 19/10
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