Device for evaluating the signal from a viscosity sensor

• US 20040045344A1
• Filed: 10/08/2003
• Published: 03/11/2004
• Est. Priority Date: 06/29/2001
• Status: Active Grant

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Jakoby, Berhard, Artzner, Johannes
• Granted Patent: US 7,089,784 B2
• Time in Patent Office: Days
• US Class Current: 73/54.02
• CPC Class Codes: G01N 11/00 Investigating flow properties of materials, e.g. viscosity, plasticity; Analysing materials by determining flow properties
• CPC Class Codes: G01N 2011/0013 Temperature compensation

Abstract

A device is provided for evaluating the signal from a viscosity sensor having an amplifying circuit. The amplification of the amplifying circuit is controlled by a temperature signal from a temperature sensor.

Claims

1. A device for evaluating the signal from a viscosity sensor (1) having an amplifying circuit (2) for the signal (VS) from the viscosity sensor,

wherein the amplifying circuit (2) has a predetermined temperature dependence for the amplification (A) of the signal (VS) from the viscosity sensor.

2. The device as recited in claim 1,

wherein the amplifying circuit (2) has an input for the signal (V_S) from the viscosity sensor and an additional input for a signal (T) from a temperature sensor (3), and the amplification (A) of the amplifying circuit (2) is controlled by the signal (T) from the temperature sensor (3).

3. The device as recited in one of the preceding claims,

wherein the viscosity sensor (1) and the temperature sensor (2) are situated in immediate proximity to one another in a measurement liquid.

4. The device as recited in one of the preceding claims,

wherein the signal (V_S) from the viscosity sensor (1) is dependent on the temperature (T) and the constants (K₁ and K₂) according to the following formula:

VS≈

k₁+k₂T.

5. The device as recited in one of the preceding claims, wherein an amplification (A) of the amplifying circuit (2) is dependent on the temperature (T) and the constants (C₁ and C₂) according to the following formula:

A≈

1/(c₁+c₂T).