# US 10,502,341 B2 · Optical microphone to diagnose actuators > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,502,341 B2 - Document ID: US10502341B2 - Status: Granted - Kind: B2 - Application number: 15/874,260 - Filed: 2018-01-18 - Published: 2018-07-19 - Granted: 2019-12-10 - Earliest claimed: 2017-01-18 - Assignees: Samson Aktiengesellschaft - Applicants: Samson Aktiengesellschaft - Inventors: Andreas Widl; Gerhard Widl; Stefan Unland; Uwe Schwab - Web page: https://patentgrep.com/patent/US10502341B2 ## CPC - F16K 37/0083: {by measuring valve parameters} - F16K 37/0041: {for measuring valve parameters (F16K37/0033 takes precedence)} - F16K 37/005: {for measuring fluid parameters (F16K37/0033 takes precedence)} - F16K 37/0058: {Optical means, e.g. light transmission, observation ports (F16K37/0075 takes precedence)} - G01H 9/00: Measuring mechanical vibrations or ultrasonic, sonic or infrasonic waves by using radiation-sensitive means, e.g. optical means - G01M 3/025: {Details with respect to the testing of engines or engine parts} - G01M 3/24: using infrasonic, sonic or ultrasonic vibrations - G01M 3/38: by using light (G01M3/02 takes precedence) - G01N 29/036: by measuring frequency or resonance of acoustic waves - H04R 1/028: {associated with devices performing functions other than acoustics, e.g. electric candles} - H04R 23/008: {using optical signals for detecting or generating sound} - H04R 29/004: {for microphones (H04R29/007 takes precedence)} - E21B 47/107: using acoustic means - F16K: VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING {(devices for emptying and evacuating the excess liquid in valves or conduits F16L55/07)} - G01H: MEASUREMENT OF MECHANICAL VIBRATIONS OR ULTRASONIC, SONIC OR INFRASONIC WAVES - G01M: TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR - 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) - H04R: LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; ELECTRIC HEARING AIDS; PUBLIC ADDRESS SYSTEMS (producing sounds with frequency not determined by supply frequency G10K) - E21B: EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS ## Abstract A diagnostic system and method to function-monitor an actuator to affect a process medium stream of a process engineering plant can include an optical microphone allocated to the actuator and a diagnostic electronics. The optical microphone can be configured to measure an acoustic, actuator-specific operating signal, as leakage sound and cavitation sound, based on electromagnetic radiation that is affected by the acoustic, actuator-specific operating signal, and generate an electrical measuring signal based on the measured acoustic, actuator-specific operating signal. The diagnostic electronics can be configured to receive and store, process, and/or transmit the electrical measuring signal. ## Claims ### Claim 1 A diagnostic system to function-monitor an actuator to affect a process medium stream of a process engineering plant, comprising: an optical microphone allocated to the actuator and arranged inside of a housing of the actuator in which the process medium stream flows, the optical microphone being orientated to a valve closer, a valve seat, a valve cage, and/or a valve rod, wherein the optical microphone is configured to: measure an acoustic, actuator-specific operating signal, as leakage sound and cavitation sound, based on electromagnetic radiation that is affected by the acoustic, actuator-specific operating signal, and generate an electrical measuring signal based on the measured acoustic, actuator-specific operating signal; and diagnostic electronics that are configured to receive and store, process, and/or transmit the electrical measuring signal. ### Claim 2 (depends on 1) The diagnostic system according to claim 1, wherein the optical microphone is configured to monitor a change of a refraction index of air in a course of sound waves of the acoustic, actuator-specific operating signal to optically measure sound pressure. ### Claim 3 (depends on 1) The diagnostic system according to claim 1, wherein: the optical microphone is arranged in a conduit of the process engineering plant that leads the process medium stream, wherein the optical microphone is orientated to the inside of the housing of the actuator. ### Claim 4 (depends on 1) The diagnostic system according to claim 1, further comprising a piezoelectric structure-borne sound sensor or a sound sensor with a diaphragm, wherein measuring data of the sensor are forwarded to the diagnostic electronics and the diagnostic electronics is configured to evaluate the processing of the electrical measuring signal being generated by the optical microphone. ### Claim 5 (depends on 2) The diagnostic system according to claim 2, wherein the optical microphone comprises a light source including a laser diode, and a measuring head coupled to the light source by an optical fiber cable in such a way that the light source and the measuring head are movable relative to each other, the measuring head including at least one beam splitter configured to create a first light beam that is exposed to the sound waves of the acoustic operating signal, and a second light beam that at least partially follows a path that is protected against the sound waves. ### Claim 6 (depends on 1) The diagnostic system according to claim 1, wherein the actuator is a control valve. ### Claim 7 (depends on 1) The diagnostic system according to claim 1, wherein the process engineering plant is a chemical plant, a food processing plant, or a power plant. ### Claim 8 (depends on 1) An actuator adapted to affect a process medium stream of a process engineering plant comprising: a pneumatic actuating drive configured to operate the actuator; and the diagnostic system according to claim 1. ### Claim 9 (depends on 1) The diagnostic system according to claim 1, wherein the optical microphone is arranged in a pneumatic conduit of a pneumatic actuating drive system of the actuator, the optical microphone being orientated to a magnetic valve of a positioner of the actuator, and/or the optical microphone being arranged in a pneumatic working chamber of a pneumatic actuating drive of the actuator, the optical microphone being orientated to a diaphragm or a bellow of the actuating drive. ### Claim 10 (depends on 1) The diagnostic system according claim 1, further comprising an adjuster configured to move at least one part of the optical microphone relative to a spatially defined sound field at the actuator. ### Claim 11 (depends on 10) The diagnostic system according to claim 10, wherein the adjuster comprises an electric drive having a piezoelectric material and/or that is fed with electric energy being extracted from the process medium stream or from an auxiliary energy source including a pneumatic pressure source. ### Claim 12 (depends on 1) The diagnostic system according to claim 1, wherein the optical microphone comprises a light source including a laser diode, and a measuring head coupled to the light source by an optical fiber cable such that the light source and the measuring head are movable relative to each other, the measuring head including at least one beam splitter configured to create a first light beam that is exposed to sound waves of the acoustic operating signal, and a second light beam that at least partially follows a path that is protected against the sound waves. ### Claim 13 (depends on 1) The diagnostic system according to claim 1, wherein the optical microphone lacks a diaphragm. ### Claim 14 A diagnostic system to function-monitor an actuator to affect a process medium stream of a process engineering plant, comprising: an optical microphone allocated to the actuator and arranged in a conduit of the process engineering plant that leads the process medium stream, the optical microphone being orientated to an inside of a housing of the actuator, wherein the optical microphone is configured to: measure an acoustic, actuator-specific operating signal, as leakage sound and cavitation sound, based on electromagnetic radiation that is affected by the acoustic, actuator-specific operating signal, and generate an electrical measuring signal based on the measured acoustic, actuator-specific operating signal; and diagnostic electronics that are configured to receive and store, process, and/or transmit the electrical measuring signal. ### Claim 15 A diagnostic system to function-monitor an actuator to affect a process medium stream of a process engineering plant, comprising: an optical microphone allocated to the actuator and configured to: measure an acoustic, actuator-specific operating signal, as leakage sound and cavitation sound, based on electromagnetic radiation that is affected by the acoustic, actuator-specific operating signal, and generate an electrical measuring signal based on the measured acoustic, actuator-specific operating signal; and diagnostic electronics that are configured to receive and store, process, and/or transmit the electrical measuring signal, wherein the optical microphone includes an arrangement of at least two optical sub-microphones configured to generate respective measuring signals to conduct a three-dimensional resolution of a sound field of the acoustic, actuator-specific operating signal, the arrangement of at least two sub-microphones being configured to perform the three dimensional resolution of the sound field in such a way that the arrangement localizes a sound source and/or determines the sound velocity. ### Claim 16 (depends on 15) The diagnostic system according to claim 15, wherein the sound source is of a leakage or a cavitation.