The Singer Company

Malcolm W Cornforth

Charles W Albrecht

Robert S Jacobsen

A calibration system for a mechanical gas volume corrector which has a first shaft turned at a rate corresponding to the otherwise uncorrected volumetric flow rate through the meter, a second shaft, a variable ratio transmission coupled between the first and second shafts, and a mechanism for altering the ratio of the transmission in response to changes of a physical condition of the gas. The calibration system includes an arrangement for applying a representation of a reference state of the physical condition to the ratio altering mechanism, and indicator for indicating a fixed number of revolutions of one of the shafts, an arrangement for determining the number of revolutions of the other of the shafts corresponding to the fixed number of revolutions of the one shaft, and a calculator for determining and displaying the ratio of the other shaft revolution number to the fixed number. The calibration system also includes an adjustment mechanism for changing the zero setting and the span (or gain) of the ratio altering mechanism.

Calibration system for mechanical gas volume corrector

A gas flow volume corrector mounted on a flow meter is provided with a microprocessor which calculates a corrected volume each time the meter measures a unit volume of flowing gas. Customer supplied data as to base conditions, specific gravity and gas composition are utilized to calculate supercompressibility values. These values are then processed to provide a plurality of constants which define calculation equations. The constants are stored in the corrector on a diode matrix card or PROM and are utilized each time the meter measures a unit volume of flowing gas for calculating the corrected volume. To conserve memory space, integer arithmetic, rather than floating point arithmetic, is utilized in the calculations.

Apparatus for correcting measured gas flow

A conventional fluid flow meter provides a single pulse output signal for each uncorrected unit volume flow. A monostable multivibrator (MV) is triggered by said meter signal and provides a gating signal for a 1 MHZ oscillator to produce a pulse train. A temperature sensor senses the fluid flow at the meter and controls the monostable MV so that the number of pulses in said pulse train is inversely proportional to the absolute temperature of the fluid flow. A preset down counter derives from said pulse train a number representing the absolute temperature at the sensor. A burst generator generates a fixed number of pulses related to a predetermined base temperature. A divider divides said fixed number of pulses by said number representing the absolute temperature of the fluid flow and provides a single pulse output for each integer resulting from said division and stores the remainder from said division for use in the next division. A register accumulates the number of pulses resulting from said division and represents the corrected volume flow. The above calculation is completed in a small fraction of the time period between meter pulses. A solid state switch operates to supply power to said monostable MV and to enable said oscillator for a preset time period sufficient to permit said calculation to be completed. The switch then turns off the power supply and disables the oscillator until the next meter pulse occurs.

Growing community of inventors

Edgewater Park, NJ, United States of America

Malcolm W Cornforth