 |
|
|
|
|
|
 Title: |
US4754640:
Apparatus and method for determining the viscoelasticity of liquids
[ Derwent Title ]
|
| Country: |
US United States of America
|
| |
| Inventor: |
Fitzgerald, J. Vincent; Metuchen, NJ
Matusik, Frank J.; Piscataway, NJ
Nelson, Donald W.; Voorhees, NJ
Schrag, John L.; Madison, WI
|
| Assignee: |
National Metal and Refining Company, Ltd., Metuchen, NJ
other patents from NATIONAL METAL AND REFINING COMPANY, LTD. (393535) (approx. 6)
News, Profiles, Stocks and More about this company
|
| Published / Filed: |
1988-07-05
/ 1987-03-17
|
| Application Number: |
US1987000026869
|
| IPC Code: |
Advanced:
G01N 11/16;
Core:
G01N 11/10;
IPC-7:
G01N 11/16;
|
| U.S. Class: |
Current:
073/032.A;
073/054.02;
073/054.25;
Original:
073/054;
073/059;
|
| Field of Search: |
073/054,59,60,1 DV
137/092
|
| Priority Number: |
| 1987-03-17 |
US1987000026869 |
|
| Abstract: |
A rheometer for determining the viscoelasticity of a liquid from the mechanical impedance which the liquid presents to an oscillating surface. The incremental power required to maintain a fixed amplitude of oscillation of the surface upon immersion in the liquid is determined. The differential shift in oscillation frequency due to immersion in the liquid is also determined. By relating (i) the incremental oscillation power to mechanical resistance presented by the liquid to the oscillating surface, and (ii) the differential shift in a oscillation frequency to the mechanical reactance presented by the liquid to the oscillating surface, the viscoelasticity of the liquid is determined. Applications include laboratory measurements and process control.
|
| Attorney, Agent or Firm: |
Lessler, Arthur L. ;
|
| Primary / Asst. Examiners: |
Levy, Stewart J.; Williams, Hezron E.
|
| Maintenance Status: |
CC Certificate of Correction issued
|
| INPADOC Legal Status: |
Show legal status actions
|
| Family: |
None
|
First Claim:
Show all 10 claims |
I claim:
1. A method for determining an elastic property of a viscoelastic liquid, comprising the steps of:
- providing a transducer comprising a transducer body and a transducer tip adapted to be immersed in a viscoelastic liquid;
- driving the transducer so that the tip oscillates with a constant amplitude at the mechanical resonant frequency of the transducer, regardless of the viscous load on the tip;
- disposing the transducer tip in air, and determining the corresponding frequency of oscillation fA of the tip;
- correcting the value of fA to a value fAT for any difference in temperature between the air and the temperature of any liquid in which the tip is to be immersed, in the event the air temperature is significantly different from the temperature of the liquid;
- providing a reference liquid of known rheometric properties to be used for calibration purposes;
- immersing the transducer tip in said reference liquid, and determining the corresponding frequency of oscillation of the tip;
- determining an instrument constant as a function of the difference between the frequency fAT of the transducer tip in air and the frequency of the tip in the reference liquid;
- immersing the transducer tip in said viscoelastic liquid;
- determining the real part of the mechanical impedance of said viscoelastic liquid as a function of the increase in power required to drive said transducer in order to maintain a constant amplitude of oscillation of the tip thereof, as compared to the amount of power required to maintain said amplitude in air;
- determining the density of said viscoelastic liquid; and
- determining a parameter of said viscoelastic liquid which is a measure of the elasticity thereof, as a function of said instrument constant, real part of the mechanical impedance of said viscoelastic liquid, density, and fAT -fLT, where fLT is the frequency of oscillation of the transducer tip in said viscoelastic liquid.
|
| Background / Summary: |
Show background / summary
|
| Drawing Descriptions: |
Show drawing descriptions
|
| Description: |
Show description
|
| Forward References: |
Show 17 U.S. patent(s) that reference this one
|
