US 10,502,670 B2Granted

Temperature compensated density viscosity sensor having a resonant sensing element

AssigneeRheonics GmbH

InventorsJoseph H. Goodbread, Sunil Kumar, Klaus Haeusler, Bernhard Zybach

Life of this patent

Estimating the term…

Loading patent…

Abstract

A fluid density measurement device that includes a housing, defining a chamber and an aperture; a resonator having length that is at least 5 times greater than its smallest diameter and having a longitudinal axis and a nodal plane, transverse to the longitudinal axis. The resonator further includes a tube having a first end and a second end; a second-end closure, closing the second end; and a drive rod centrally attached to the second-end closure and extending to the tube first end. Further, the device includes a resonator transducer assembly and the resonator is sealingly joined to the aperture at the nodal plane, so that an enclosed portion extends into the chamber and an exposed portion extends outside of the chamber, and wherein the chamber tends to assume the temperature of the exposed resonator portion, causing the resonator to be isothermal.

Claims18

Dependent claims

A method of measuring density of a target fluid, comprising the steps

(a) providing a fluid density measurement device, including:
(i) a housing, defining a chamber and an aperture;
(ii) a resonator having length that is at least 5 times greater than its smallest diameter and having a longitudinal axis and nodal plane, transverse to said longitudinal axis, and that includes a tube having a first end and a second end and being closed at said second end by a second-end closure, and being attached to said housing at said nodal plane, which is sealingly joined to said aperture, blocking fluid ingress, and so that an enclosed resonator portion extends into said chamber and an exposed resonator portion extends outside of said chamber;
and further including a drive rod centrally attached to said second-end closure and extending into said enclosed resonator portion;
(iii) wherein said second-end closure includes a fluid end mass that would define a non-round shape on a plane cutting through said end mass transversely to said longitudinal axis and wherein said resonator is driven to vibrate torsionally about its longitudinal axis, and said target fluid is displaced by resultant rotational vibration of said end mass;
and
(iv) a transducer assembly;
and
(b) placing said exposed portion of said resonator in said target fluid;
(c) placing and maintaining said resonator into an isothermal state;
(d) using said transducer assembly to excite said resonator such that said exposed resonator portion vibrates perpendicularly to a portion of its own surface and to sense resultant resonator vibrations;
and
(e) analyzing said resultant vibrations to determine density of said target fluid.

10 more elements

A fluid density measurement device, including:

(a) a housing, defining a chamber and an aperture;
(b) a resonator having length that is at least 4 times greater than its smallest diameter and having a longitudinal axis and nodal plane, transverse to said longitudinal axis, and that includes:
(i) a tube having a first end and a second end;
(ii) a second-end closure, closing said second end;
and
(c) a drive rod centrally attached to said second-end closure and extending to said tube first end;
(d) a resonator transducer assembly;
(e) wherein said resonator is sealingly joined to said aperture at said nodal plane, blocking fluid ingress, and so that an enclosed resonator portion extends into said chamber and an exposed resonator portion extends outside of said chamber, and wherein said resonator transducer assembly drives said resonator such that said exposed resonator portion vibrates perpendicularly to a portion of its own surface;
and
(f) wherein said measurement device further includes a temperature sensor located in said exposed resonator portion, and also further includes a temperature control element positioned to control temperature of said chamber and being responsive to said temperature sensor to control temperature of said chamber and thereby said enclosed resonator portion to equal that of said exposed resonator portion, so that said resonator is placed and maintained in an isothermal state.

7 more elements

Dependencies are inferred from the claim text.

Facts

Application: 15/566,675Filed 14 Apr 2016 · us provisional application
Priority: 14 Apr 2015
Published: US 2019/0003947 A13 Jan 2019
Granted: 10 Dec 2019
Term ends: Not estimatedThe source records don’t support an estimate.

Classification8 codes

G01N 9/002
Investigating density or specific gravity of materials; Analysing materials by determining density or specific gravity: using variation of the…
G01N 11/10
Investigating flow properties of materials, e.g. viscosity, plasticity; Analysing materials by determining flow properties: by moving a body…
G01N 11/16
By moving a body within the material: by measuring damping effect upon oscillatory body
G01N 11/162
By measuring damping effect upon oscillatory body: oscillations being torsional, e.g. produced by rotating bodies

Family

Application62/147,180Us provisional application · filed 14 Apr 2015
US 2019/0003947 A1Pre-grant publication · published 3 Jan 2019
US 10,502,670 B2This patent

From the US filing history. Foreign family members aren’t listed.

Timeline

Citations

Open elsewhere

Building an agent or pulling many patents? Use the API or MCP server instead of scraping pages. Get an API key