# US 2021/0080366 A1 · Oscillator for Density Measurement of a Liquid

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 2021/0080366 A1
- Document ID: US20210080366A1
- Status: Published application
- Kind: A1
- Application number: 17/017,387
- Filed: 2020-09-10
- Published: 2021-03-18
- Earliest claimed: 2019-09-12
- Inventors: Wolfgang Belitsch
- Web page: https://patentgrep.com/patent/US20210080366A1

## CPC

- G01N 9/002: {using variation of the resonant frequency of an element vibrating in contact with the material submitted to analysis (G01N9/34 takes precedence)}
- G01K 7/22: the element being a non-linear resistance, e.g. thermistor (G01K7/26 takes precedence)
- G01K 13/00: Thermometers specially adapted for specific purposes
- G01N 2009/006: {vibrating tube, tuning fork}
- G01N: INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES (measuring or testing apparatus or processes other than immunoassay, involving enzymes or microorganisms C12M, C12Q)
- G01K: MEASURING TEMPERATURE; MEASURING QUANTITY OF HEAT; THERMALLY-SENSITIVE ELEMENTS NOT OTHERWISE PROVIDED FOR (radiation pyrometry G01J5/00)

## Abstract

An oscillator for density measurement of a liquid, including a counter mass and a container for the liquid. The oscillator is made of metal and the container has two identical resonator tubes, which are clamped into the counter mass in parallel to each other, and a connecting tube connecting the resonator tubes. The resonator tubes can be set into a resonance oscillation in which a common centre of gravity of the resonator tubes remains at rest during the resonance oscillation. The oscillator also includes a web located between the counter mass and the connecting tube, which web spaces the resonator tubes from each other in such a way that the lengths (L) of the resonator tubes enclosed between the counter mass and the web can be set into a diametrically opposite oscillation on the basis of which the density of the liquid located in the oscillator can be determined.

## Claims

### Claim at position 1

-9. (canceled)

### Claim 10

An oscillator for density measurement of a liquid, comprising a counter mass and a container for the liquid, wherein the oscillator is made of metal and the container has two identical resonator tubes, which are clamped into the counter mass essentially in parallel to each other, and a connecting tube connecting the resonator tubes, wherein the resonator tubes can be set into a resonance oscillation in which the common centre of gravity of the resonator tubes remains at rest during the resonance oscillation, and the oscillator further comprises a web located between the counter mass and the connecting tube, which web spaces the resonator tubes from each other in such a way that respective lengths (L) of the resonator tubes enclosed between the counter mass and the web can be set into a diametrically opposite oscillation on the basis of which the density of the liquid located in the oscillator can be determined.

### Claim 11 (depends on 10)

An oscillator according to claim 10, wherein the resonator tubes and the connecting tube are manufactured in one piece as a curved U-shaped tube.

### Claim 12 (depends on 10)

An oscillator according to claim 10, wherein a thermistor is attached to the connecting tube.

### Claim 13 (depends on 10)

A system for density measurement of a liquid, the system comprising the oscillator according to claim 10 and an excitation unit operable to excite the resonator tubes in such a way that the lengths (L) will oscillate in a diametrically opposite way with a temporally constant centre of gravity.

### Claim 14 (depends on 13)

A system according to claim 13, comprising a measuring device operable to determined a frequency of the oscillation of the lengths (L), and an evaluation unit operable to determined the density of the liquid from the frequency.

### Claim 15 (depends on 12, 14)

A system according to claim 14, comprising the oscillator according to claim 12, wherein the evaluation device is operable to record a temperature measured by the temperature sensor (when the density is being determined, and the evaluation device is operable to calculate the density for a predefined temperature.

### Claim 16 (depends on 15)

A system according to claim 15, wherein the system comprises a temperature control unit operable to bring the oscillator to a predetermined temperature, and wherein the evaluation device is operable to record the temporal density gradient during a change in temperature.

### Claim 17 (depends on 16)

A system according to claim 16, wherein the evaluation unit is operable to record the temporal density gradient over a first trial period, and is operable to record the density gradient over a second trial period after the liquid has been changed and is operable to continue to record the density gradient after the second trial period if the density gradient of the first trial period essentially corresponds to the density gradient of the second trial period.

### Claim 18 (depends on 13)

A system according to claim 13, wherein the oscillator is mounted within a receptacle filled with helium.