Ultrasonic particle measuring system

Patent metadata

Field	Value
Publication number	US-9170240-B2
Application number	US-201113808649-A
Country	US
Kind code	B2
Filing date	Jun 20, 2011
Priority date	Jul 8, 2010
Publication date	Oct 27, 2015
Grant date	Oct 27, 2015

Abstract

An ultrasonic particle measuring system having an ultrasonic transducer with at least one ultrasonic transducer element and at least one coupling element, wherein, during operation, acoustic signals are transmittable and receivable by the ultrasonic transducer element via the coupling element, wherein the coupling element is embodied as an acoustic lens, and the ultrasonic, particle measuring system has an evaluation unit suitable for amplitude analysis of reflection signals of acoustic signals reflected from particles to the ultrasonic transducer, and wherein, with the evaluation unit, amplitudes of reflection signals in a predetermined time interval are countable, which are greater than a predetermined threshold value.

First claim

The invention claimed is:

1. An ultrasonic particle measuring system, comprising:
an ultrasonic transducer;
which has at least one ultrasonic transducer element;
at least one coupling element;
a control unit; and
an evaluation unit suitable for amplitude analysis of reflection signals of acoustic signals reflected from particles to said ultrasonic transducer, wherein:
during operation, acoustic signals are transmittable and receivable by said ultrasonic transducer element via said coupling element;
said coupling element is embodied as an acoustic lens;
said ultrasonic, with said evaluation unit, amplitudes of reflection signals in a predetermined time interval are countable, which are greater than a predetermined threshold value;
said ultrasonic transducer element is suitable for transmitting a first acoustic signal of a first frequency, and is suitable for transmitting a second acoustic signal of a second frequency;
said control unit, is suitable for exciting said ultrasonic transducer element for transmitting the first acoustic signal and for exciting said ultrasonic transducer element for transmitting the second acoustic signal; and
the first frequency is different from the second frequency;
wherein particle sizes of the particles in the measured medium are ascertained from the amplitudes of reflection signals received, which are greater than a predetermined threshold value; and
wherein particle concentration in the measured medium is ascertained from the number of amplitudes of reflection signals received in a predetermined time interval with amplitudes greater than the predetermined threshold value.

2. The ultrasonic particle measuring system as claimed in claim 1 , wherein:
the first frequency amounts to at least 2 MHz and the second frequency amounts to, at most, 10 MHz.

3. The ultrasonic particle measuring system as claimed in claim 2 , wherein:
the ultrasonic, particle measuring system is so embodied that the ratio of focal length of an acoustic lens in aqueous measured media to a diameter of said measuring tube amounts to at least 0.2.

4. The ultrasonic particle measuring system as claimed in claim 1 , wherein:
said ultrasonic transducer is arranged in a measuring tube for transmitting the first acoustic signal and the second acoustic signal along a shared signal path; and
the shared signal path is so excited that it has an angle of 90° to said measuring tube axis.

5. The ultrasonic particle measuring system as claimed in claim 1 , wherein:
at least said coupling element is embodied as a planoconcave, acoustic lens.

6. The ultrasonic particle measuring system as claimed in claim 1 , wherein:
at least said coupling element is embodied as an acoustic, Fresnel lens.

7. The ultrasonic particle measuring system as claimed in claim 1 , wherein:
at least said coupling element is manufactured of a polymer.

8. The ultrasonic particle measuring system as claimed in claim 1 , wherein:
said ultrasonic transducer element is adhered directly to a second contact surface of said coupling element.

9. The ultrasonic particle measuring system as claimed in claim 1 , wherein:
the first frequency and the second frequency are adjustable.

10. The ultrasonic particle measuring system as claimed in claim 1 , wherein:
said measuring tube has an approximately circularly round cross section with a diameter of at least 20 mm.

11. The ultrasonic particle measurement system as claimed in claim 1 , wherein
the ultrasonic particle measuring system is arranged in a pipeline system downstream from a particle filter.

12. A method for registering particles in a measured medium with an ultrasonic transducer, which is arranged in a measuring tube, comprising the steps of:
producing acoustic signals by the ultrasonic transducer for registering particles in the measured medium by means of amplitude analysis of reflection signals of the acoustic signals reflected from the particles to the ultrasonic transducer; and
focusing at least the acoustic signals produced by the ultrasonic transducer via an acoustic lens, wherein:
the frequency of the acoustic signals produced by the ultrasonic transducer is set within a predetermined frequency range according to a predetermined specification;
wherein particle sizes of the particles in the measured medium are ascertained from the amplitudes of the reflection signals received, which are greater than a predetermined threshold value; and
wherein particle concentration in the measured medium is ascertained from the number of amplitudes of reflection signals received in a predetermined time interval with amplitudes greater than the predetermined threshold value.

13. The method as claimed in claim 12 , wherein:
the threshold value is predetermined as a function of the frequency of the acoustic signals produced by the ultrasonic transducer.

14. The method as claimed in claim 12 , wherein:
the ultrasonic transducer is excited for transmitting the acoustic signal with a frequency greater than 2 MHz.

Assignees

• Lin Yaoying
• Kissling Beat
• Drahm Wolfgang
• Frohlich Thomas
• Flowtec Ag

Inventors

• Lin Yaoying
• Kissling Beat
• Drahm Wolfgang
• Frohlich Thomas

Classifications

• G01N15/02 Primary

  Investigating particle size or size distribution (by measuring osmotic pressure G01N7/10; investigating sedimentation of particle suspensions G01N15/04; investigating individual particles G01N15/10) · CPC title

• G01N2291/02408

  Solids in gases, e.g. particle suspensions · CPC title

• G01N29/348

  with frequency characteristics, e.g. single frequency signals, chirp signals (measuring frequency of mechanical vibrations or acoustic waves in general G01H1/06, G01H3/04; measuring frequency or analysing frequency spectra G01R23/00) · CPC title

• G01N15/06

  Investigating concentration of particle suspensions (by weighing G01N5/00; investigating sedimentation of particle suspensions G01N15/04; investigating individual particles G01N15/10) · CPC title

• G01N29/221

  Arrangements for directing or focusing the acoustical waves (electronic orientation or focusing G01N29/262; sound directing or focusing G10K11/26; mechanical steering of sound transducers or their beams G10K11/35) · CPC title