SYSTEM AND METHOD FOR DETECTING A ROTATIONAL SPEED OF A TURBOCHARGER

• US 20150114096A1
• Filed: 01/04/2013
• Published: 04/30/2015
• Est. Priority Date: 01/10/2012
• Status: Active Grant

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Eichel, Dirk
• Granted Patent: US 9,581,611 B2
• Time in Patent Office: Days
• US Class Current: 73/114.25
• CPC Class Codes: G01P 3/44 for measuring angular speed G01P3/56 takes precedence
• CPC Class Codes: G01S 13/02 Systems using reflection of radio waves, e.g. primary radar systems; Analogous systems
• CPC Class Codes: G01S 13/32 using transmission of continuous waves, whether amplitude-, frequency-, or phase-modulated, or unmodulated
• CPC Class Codes: G01S 13/88 Radar or analogous systems specially adapted for specific applications electromagnetic prospecting or detecting of objects, e.g. near-field detection, G01V3/00
• CPC Class Codes: G01S 7/415 Identification of targets based on measurements of movement associated with the target

Abstract

A system for detecting a rotational speed of a turbocharger includes: a rotational speed sensor unit which includes a radar transmitter for emitting radar waves and a radar receiver for receiving the radar waves and which is designed to detect radar waves reflected by a machine element of the turbocharger and to provide them as a measuring signal; and an evaluation unit which is coupled to the rotational speed sensor unit and is designed to check whether the reflected radar waves are detectable by the radar receiver based on a predetermined criterion and to ascertain the rotational speed of the turbocharger based on an evaluation of the measuring signal.

Claims

1-12. -12. (canceled)

13. A system for detecting a rotational speed of a turbocharger, comprising:

a rotational speed sensor unit which includes (i) a radar transmitter emitting radar waves, and (ii) a radar receiver receiving the radar waves, wherein the rotational speed sensor unit is configured to detect radar waves reflected by at least one machine element of the turbocharger and provide the detected radar waves as a measuring signal; and

an evaluation unit coupled to the rotational speed sensor unit and configured to;

check, based on a predetermined criterion, whether the reflected radar waves are detectable by the radar receiver; and

ascertain the rotational speed of the turbocharger based on an evaluation of the measuring signal.

14. The system as recited in claim 13, wherein the predetermined criterion includes a degree of a formation of a periodicity of the measuring signal.

15. The system as recited in claim 14, wherein the degree of the formation of the periodicity of the measuring signal is determined by the evaluation unit with the aid of at least one of a spectrum analysis and a Fourier transform of the measuring signal.

16. The system as recited in claim 14, wherein the evaluation unit carries out the evaluation of the measuring signal for at least as many periods as the number of machine elements included in the turbocharger.

17. The system as recited in claim 16, wherein the machine elements are compressor blades.

18. The system as recited in claim 17, wherein the system is configured as a vehicle diagnostic system.

19. The system as recited in claim 17, wherein the rotational speed sensor unit is focused on the turbocharger at a distance of 1 cm to 30 cm.

20. The system as recited in claim 17, wherein the radar transmitter and the radar receiver are configured to transmit and receive within a frequency range from 2200 MHz to 12 GHz.

21. The system as recited in claim 17, further comprising:

a display unit coupled to the evaluation unit and configured to display (i) a result of a check of the position of the rotational speed sensor unit and (ii) the ascertained rotational speed of the turbocharger.

22. A method for detecting a rotational speed of a turbocharger, comprising:

emitting radar waves by a radar transmitter of a rotational speed sensor unit;

receiving, by a radar receiver of the rotational speed sensor unit, the radar waves which are reflected by a machine element of the turbocharger;

providing the received radar waves as a measuring signal;

checking, based on a predetermined criterion, whether the reflected radar waves are detected by the radar receiver; and

ascertaining, by an evaluation unit, the rotational speed of the turbocharger based on an evaluation of the measuring signal.

23. The method as recited in claim 22, wherein a degree of a formation of a periodicity of the measuring signal is utilized as the predetermined criterion.

24. The method as recited in claim 23, wherein the degree of the formation of the periodicity of the measuring signal is determined by the evaluation unit with the aid of at least one of a spectrum analysis, a Fourier transform of the measuring signal, and counting of zero crossings of the measuring signal.