Magnetic flowmeter with a direct-coupled optical output increases accuracy and operates independently of other system inputs. The design includes simple external adjustment and signal amplitude control

Wolpin, E. G.

English

NASA Technical Reports Server

nDecember 1965	 Brief 65-10395 
NASA TECH BRIEF 
NASA Tech Briefs are issued by the Technology Utilization Division to summarize specific 
technical innovations derived from the space program. Copies are available to the public from 
the Clearinghouse for Federal Scientific and Technical Information, Springfield, Virginia, 22151. 
Optical Output Enhances Flowmeter Accuracy 
The problem: Accuracy in magnetic flowmeters is 
degraded by such things as ripple current, power input 
amplitude variations, and changes in duty cycle. A 
flowmeter is needed that operates independently of 
other system inputs. 
The solution: A flowmeter with a direct-coupled 
optical output. The design includes simple' external 
adjustment and signal amplitude control. 
How it's done: An optical encoder disk is mounted 
on the shaft that is driven by the flow wheel in the 
measured fluid. An optical sensor consisting of a light 
source, collimating lens, and photodiode is so 
mounted that the encoder disk interrupts the beam 
of light from the light source to the photodiode. A
slot or other configuration cut out of the disk causes 
the light source to illuminate the photodiode as it in-
dexes with the beam of light. The design includes a 
solenoid operated mounting for the optical sensor so 
it may be moved up out of the encoder disk path for 
calibration and adjustment. The spring mounted sen-
sor, frame returns to operating position when the sole-
noid is deenergized. 
Notes: 
1. Signal amplitude is controlled by controlling light 
source intensity. 
2. By means of a servo and feedback, this device 
could be used to accurately regulate the flow of a 
liquid.
(continued overleaf)
	 - 
This document was prepared under the sponsorship of the National
	 Government assumes any liability resulting from the use of the 
Aeronautics and Space Administration, Neither the United States
	 information contained in this document, or warrants that such use 
Government nor any person acting on behalf of the United States
	 will be free from privately ownedrights,
https://ntrs.nasa.gov/search.jsp?R=19650000392 2020-03-11T17:25:26+00:00Z
3. Inquiries concerning this innovation may be di-
rected to:
Technology Utilization Officer 
Marshall Space Flight Center 
Huntsville, Alabama, 35812 
Reference: B65-10395 
Brief 65-10395
Patent status: NASA encourages commercial use 
of this innovation. No patent action is contemplated 
by NASA.
Source: Edward G. Wolpin of North
American Aviation, Inc.,
under contract to Marshall 
Space Flight Center
(M-FS-482) 
Category 02


Optical output enhances flowmeter accuracy

Abstract

Similar works

Full text

Available Versions

NASA Technical Reports Server