Sensor assemblies used to detect proximity of material to microwave element

The application generally relates to sensor assemblies, and more particularly to sensor assemblies used to detect the proximity of an object to a microwave element.

At least some known sensor systems have been used to detect the proximity of objects such as metals, liquids or other material variants. The proximity of an object to a sensor can be used in a variety of applications such as surveillance systems and / or control systems. For example, such detection methods are used to detect the vibration and / or position of objects in various systems such as, but not limited to, manufacturing systems, surveillance systems, processing systems, chemical systems and / or safety systems. can do.

Known detection methods can be performed using a vortex current sensor, a magnetic pickup sensor or a capacitance sensor. However, such sensors usually have a limited range of measurement and therefore generally have a limited location and environment in which such a sensor can be used. Moreover, such sensors usually have a slow frequency response, and thus the accuracy of such sensors is also limited in some cases. Therefore, the advantages of known detection systems are limited in some cases.

In one embodiment, the sensor assembly is disclosed. The sensor assembly includes a signal generator configured to generate at least one microwave signal, a coupler connected to the signal generator, a microwave element coupled to the coupler, and a coupler connected to the coupler. Contains the processed module. The microwave element is configured to generate an electromagnetic field as a function of the at least one microwave signal. The microwave element is structured to reflect the loading signal to the coupler when the object interacts with the electromagnetic field. The processing module is configured to process the loading signal using a reference signal to generate a data signal that represents the proximity of the object to the microwave element. The data signal defines the sub-microwave frequency.

In other embodiments, the power system is disclosed. The power system includes a component, at least one sensor assembly located adjacent to the component, and an electrical device coupled to at least one sensor assembly. At least one sensor assembly includes a coupler, a microwave element coupled to the coupler, and a processing module coupled to the coupler. The microwave element is configured to generate an electromagnetic field as a function of at least one microwave signal. The microwave element is configured to reflect the loading signal to the coupler when the object interacts with the electromagnetic field. The processing module is configured to process the loading signal using a reference signal to generate a data signal that represents the proximity of the object to the microwave element. The data signal defines frequencies below at least about 30 kHz.

In yet another embodiment, the method used to detect the proximity of an object is disclosed. This method involves the step of generating an electromagnetic field in the microwave element as a function of at least one microwave signal, and the microwave element to guide the loading signal to the microwave element when the object interacts with the electromagnetic field. A step of detuning the data signal and a step of generating a data signal from the loading signal and the reference signal in the processing module are included. The data signal represents the proximity of the object to the microwave element. The data signal defines the sub-microwave frequency.

<figref num="1">FIG. 6 is a block diagram of an exemplary sensor assembly that can be used to detect the proximity of an object.</figref><figref num="2">FIG. 6 is a block diagram of an alternative sensor assembly that can be used to detect the proximity of an object.</figref><figref num="3">It is a block diagram of an exemplary electric power system.</figref><figref num="4">FIG. 5 is a flow diagram of an exemplary method that can be used to detect the proximity of an object according to the present disclosure.</figref>

The exemplary methods and assemblies described herein overcome at least some of the drawbacks of known sensor systems used to detect the proximity of objects. In particular, according to the embodiments described herein, an assembly that can be used to detect the proximity of an object to a microwave element is provided, while representing the proximity of an object. A sub-microwave frequency data signal is provided. The following description illustrates some embodiments as an unrestricted example.

FIG. 1 shows an exemplary sensor assembly 100 that can be used to detect the proximity of an object 102. In this exemplary embodiment, the object 102 may be a solid such as a liquid, metal and / or any other product, or an object that interacts with the sensor assembly described herein. To be clear, the methods and sensor assemblies described herein are not limited to any one particular application and / or system and will be described to those of skill in the art herein. It will be appreciated that methods and sensor assemblies can be used in connection with various applications, machines and / or systems, such as, but not limited to, the gas turbine engines described below.

In this exemplary embodiment, the sensor assembly 100 includes a signal generator 104 and a coupler 106 coupled to the signal generator 104. As used herein, the terms "connected" and "joined" are not limited to direct mechanical and / or electrical connections between components, but between multiple components. Note that it is also possible to include indirect mechanical and / or electrical connections. The signal generator 104 is configured to generate at least one electrical signal of microwave frequency (hereinafter referred to as "microwave signal"). Further, the sensor assembly 100 includes microwave elements 108 such as, but not limited to, microwave emitters, microwave antennas or other suitable microwave devices. The microwave element 108 is connected to the coupler 106. In this exemplary embodiment, the microwave element 108 generates an electromagnetic field 110 as a function of the microwave signal generated by the signal generator 104. As used herein, the term "microwave" means a signal or receives and receives signals with frequencies between about 300 MHz (MHz) and about 300 GHz (GHz). / Or means the component to send. For example, a microwave signal can have a frequency of 3.25 GHz or 5.8 GHz.

It is described herein as compared to known eddy current sensors, magnetic pickup sensors or capacitive sensors currently used to detect the proximity of an object by using the microwave element 108. , The detection range of the sensor assembly used to detect the proximity of the object 102 to the microwave element 108 can be substantially extended. In addition, by using the microwave element 108, the positioning and / or position of the sensor assembly described herein is compared to the known vortex current sensor, magnetic pickup sensor and / or capacitive sensor. The restrictions are significantly relaxed. In addition, the sensor assembly 100 described herein provides more accurate measurements than known sensor assemblies because the microwave element 108 has a faster frequency response when compared to known sensors. be able to.

The sensor assembly 100 includes a processing module 112 connected to the coupler 106. In this exemplary embodiment, the processing module 112 includes a frequency mixer 114 and a filter 116 connected to the frequency mixer 114.

During operation, the signal generator 104 generates a microwave signal equal to or approximately equal to the resonant frequency of the microwave element 108. The signal generator 104 transmits a microwave signal to the coupler 106. The combiner 106 transmits the received microwave signal to the microwave element 108. Further, in this particular embodiment, the coupler 106 transmits a reference signal to the processing module 112. More specifically, the coupler 106 transmits a reference signal derived from the microwave signal, which is substantially equal to the microwave signal, to the frequency mixer 114. In other embodiments, the reference signal may be different from the microwave signal.

When the microwave signal is transmitted via the microwave element 108, the electromagnetic field 110 is emitted outward from the microwave element 108. When an object such as the object 102 enters the electromagnetic field 110, an electromagnetic coupling can be generated between the object 102 and the electromagnetic field 110. Due to the presence of the object 102 in the electromagnetic field 110, the inductive and / or capacitive effect within the object 102 destroys the electromagnetic field 110, which causes at least a portion of the electromagnetic field 110 to be an electric current and / or an electric charge. It will be inductively coupled and / or capacitively coupled to the object 102. In such an example, the microwave element 108 is detuned (ie, the resonant frequency of the microwave element 108 decreases and / or changes, and so on) and the load is guided to the microwave element 108. When the load is guided to the microwave element 108, the reflection of the microwave signal (hereinafter referred to as load signal) in the microwave element 108 and the coupler 106 is transmitted to the processing module 112 via the coupler 106. Ru. The loading signal represents the proximity of the object 102 to the microwave element 108 and can indicate the presence of the object 102 in the electromagnetic field 110 and / or the distance from the microwave element 108 to the object 102.

Due to the object 102, the induced loading signal has a smaller power amplitude and / or the induced loading signal is the power amplitude and / or the power amplitude of the microwave signal supplied from the signal generator 104 to the microwave element 108. Or it is a power amplitude of a phase different from the phase. More generally, the loading signal is substantially the same as the microwave signal, except for the effect of the object 102 on the electromagnetic field 110. Therefore, the difference between the microwave signal and the loading signal represents the proximity of the object 102 to the microwave element 108.

The loading signal is transmitted to the processing module 112 via the coupler 106. The processing module 112 receives the loading signal and processes it in combination with the reference signal to generate a data signal representing the proximity of the object 102 to the microwave element 108. The data signal defines the sub-microwave frequency.

More specifically, the frequency mixer 114 shifts the frequency of the loading signal based on the frequency of the reference signal, and vice versa. In this exemplary embodiment, the frequency mixer 114 adds or subtracts the frequency of the loading signal (fl) and the frequency of the reference signal (fr). Therefore, the frequency mixer 114 provides the data signal in two frequency bands, that is, the up conversion band (fl + fr) and the down conversion band (fl-fr). The resulting up-conversion band frequency is equal to or higher than the microwave frequency. On the other hand, the frequency of the resulting down conversion band is substantially the nominal frequency, thus providing a substantially DC data signal. More generally, the reference signal and the loading signal are substantially the same except for the effect of the object 102 on the electromagnetic field 110. As will be appreciated by those skilled in the art, the physical motion of the object 102 into and out of the electromagnetic field 110, and / or the physics of the object 102 within the electromagnetic field 110. Motion usually occurs at frequencies well below 300 MHz, and thus at frequencies below 300 MHz, i.e. sub-microwave frequencies.

In this exemplary embodiment, the sensor assembly 100 can achieve the range and / or frequency response provided by the microwave element 108, while allowing simple post-processing of the sub-microwave frequency data signal. can do. More specifically, by using the frequency mixer 114, a data signal within the sub-microwave frequency band is provided, and the sensor assembly described herein is the processing, handling and / of the data signal. Or the transmission can be significantly simplified. In various embodiments, a wider range of various components rated for sub-microwave frequency signals are commercially available, for example, to operate on data signals. Further, according to the present disclosure, the complexity and / or cost of board-level circuits for processing, filtering and / or transmitting the sub-microwave frequency data signal band can be reduced.

Seeing FIG. 1 again, the filter 116 is coupled between the frequency mixer 114 and the signal processor 118. In this embodiment, the filter 116 is a low pass filter structured to attenuate signals with frequencies above 30 kHz, thus passing signals with frequencies below 30 kHz. Therefore, during operation, the low-pass filter 116 passes the data signal in the down-conversion frequency band from the frequency mixer 114, while attenuating the data signal in the up-conversion frequency band. Filter 116 provides a data signal that contains only the filtered, substantially only data signals in the down-conversion frequency band. In other embodiments, it is also possible to structure a lowpass filter or other filter to pass signals of one or more frequencies while attenuating signals of other frequencies. I want to be understood.

The signal processor 118 determines the proximity of the object 102 to the microwave element 108 as a function of the filtered data signal. The signal processor 118 outputs a processed data signal indicating proximity. The signal processor 118 performs a function of processing the data signal to provide the proximity of the object 102 to the microwave element 108. The above function may be a linear function or a higher-order polynomial function. This function can represent a calibration test for each individual sensor assembly completed during manufacturing, thereby improving the sensor assembly and / or guaranteeing the accuracy of the sensor assembly. The function is stored in the signal processor 118. The signal processor 118 includes an analog-digital (A / D) converter 120 for converting the filtered data signal into a digital data signal so that the signal processor 118 can process the digital data signal. There is.

The signal processor 118 and / or A / D converter 120 shown and described in the figure is included in the processing module 112, but in other embodiments, the signal processor 118 and / or A / D converter 120 It should be appreciated that the vessel 120 may also include other modules located adjacent to and / or away from the processing module 112. In yet other embodiments, either the signal processor 118 and / or the A / D converter 120 may be omitted, and / or the data signal may be processed as described herein. Other components can also be included within the processing module 112 for filtering and / or transmission.

FIG. 2 shows an exemplary sensor assembly 200 that can be used to detect the proximity of an object 202. The sensor assembly 200 includes a signal generator 204, a coupler 206 connected to the signal generator 204, and a microwave element 208 coupled to the coupler 206. The sensor assembly 200 includes a processing module 212 coupled to the coupler 206. More specifically, the coupler 206 is coupled to the frequency mixer 214 contained within the processing module 212. During operation, the coupler 206, like the sensor assembly 100, transmits a loading signal to the frequency mixer 214.

In this exemplary embodiment, the sensor assembly 200 includes a reference signal generator 220. The reference signal generator 220 is coupled to the frequency mixer 214. The reference signal may be substantially the same as the microwave signal generated by the signal generator 204. Conversely, the reference signal may or may not be substantially the same as the microwave signal produced by the signal generator 204. As described above with reference to FIG. 1, the frequency mixer 214 provides a data signal in the down and up conversion bands during operation. The down conversion band is usually arranged at the difference between the loading signal frequency and the reference signal frequency. Therefore, by selecting a reference signal, a data signal can be provided at any desired frequency. For example, if the microwave signal defines a frequency of about 5.80 GHz and the reference signal defines a frequency of about 5.79 GHz, the down conversion band is substantially at about 10.0 Mhz.

It should be appreciated that a variety of different microwave frequencies and / or reference signal frequencies can be selected to place the data signal at any desired frequency. More specifically, the frequency of the microwave signal and / or the loaded signal is adjusted or selected, and the frequency of the data signal is set to, for example, about 200 MHz, about 100 MHz, about 100 kHz, about 30 kHz, about 20 kHz, about 5 kHz, about 1 kHz. , And / or other suitable frequencies, including any discrete sub-microwave frequency, etc., can be further limited to less than any desired value. The frequency of the data signal may be selected based on one or more environmental constraints, sensor assembly requirements, and / or the desired component for processing, filtering, and / or transmitting the data signal. Can be done.

To be clear, the filter 216 can be selected according to the position of the down conversion band. Specifically, for example, when the data signal defines a frequency of 20 kHz, the filter 216 may be a band-stop filter or a notch filter. The notch filter 216 can define the center frequency to 20kHz, ensuring that the data signal in the down conversion band passes through without attenuation beyond the nominal attenuation, while the up conversion band is consistently effective. It has enough bandwidth to ensure that it decays. In addition, the filter 216 can act to filter out noise and / or other artifacts outside the bandwidth of the filter 216 contained in the data signal.

Seeing FIG. 2 again, the sensor assembly 200 includes a probe housing 224. As shown in the figure, each of the coupler 206 and the microwave element 208 is located within the probe housing 224. The probe housing 224 can be structured to facilitate transmission and / or attachment of the electromagnetic field 210 to a particular location, machine and / or system.

Further, as shown in FIG. 2, the processing module 212 does not include a signal processor and / or an A / D converter. The data signal is therefore an analog signal to determine the proximity of the object 202 to the microwave element 208, including the presence of the object 202 in the electromagnetic field 210 and / or the distance between the object 202 and the microwave element 208. Other devices can use this analog signal.

The methods and assemblies described herein can be used for a variety of purposes. Exemplary applications can include, but are not limited to, control systems, monitoring systems, driving systems, safety systems and / or diagnostic systems. FIG. 3 shows an exemplary power system 326. The power system 326 includes component 328, at least one sensor assembly 300 located adjacent to component 328, and an electrical device 330 coupled to the sensor assembly 300. Component 328 can include, but is not limited to, gas turbine engine components such as rotary turbine shafts, turbine casings, fuel or other moving or immobile components of gas turbine engines, and the like. In this particular embodiment, component 328 includes a rotary turbine shaft that drives load 332. In this exemplary embodiment, the sensor assembly 300 is used to monitor component 328, eg, to monitor position, vibration and / or other behavior during operation. In particular, the electrical device 330 includes a monitoring system for monitoring component 328 and / or a control system for controlling component 328, if necessary, depending on the behavior being monitored. There is. For example, the electrical device 330 can stop the rotation of a component 328, such as a rotating turbine shaft, when vibration (when monitored by the sensor assembly 300) exceeds a defined threshold.

The sensor assembly 300 includes one or more of the sensor assembly embodiments described herein, or one or more of the other sensor assemblies that are consistent with one or more of the teachings of the present disclosure. Can include. In this exemplary embodiment, the sensor assembly 300 provides a data signal to the electrical device 330 to control and / or monitor component 328.

In addition to the various uses of the present disclosure, the methods and assemblies described herein can also be used to detect the proximity of objects under various conditions. In many exemplary embodiments, the method and assembly can include static detection and / or dynamic detection. Static detection can include, for example, detection of the proximity of an object to a microwave element to determine expansion and / or contraction of the object. Dynamic detection can also include, for example, detecting the proximity of an object to a microwave element to detect the movement of mechanical components, such as the vibration of a rotating turbine shaft.

FIG. 4 is an exemplary method 400 that can be used to detect the proximity of an object, such as the object 102 shown in FIG. Method 400 is described herein with reference to the sensor assembly described herein with reference to FIG. However, it should be understood that the methods described herein can be applied to a wide variety of sensor assemblies and are therefore not limited to the particular embodiment of the sensor assembly described herein. .. Instead, the sensor assemblies described herein should not be understood to be limited to the particular methods described herein.

In this exemplary embodiment, method 400 involves step 402 in which the microwave element 108 generates an electromagnetic field 110 as a function of at least one microwave signal, and when the object 102 interacts with the electromagnetic field 110, it is microwaved. A step 404 of detuning the microwave element 108 to guide the loading signal to the element 108 and a step 406 of the processing module 112 generating a data signal from the loading and reference signals are included. The data signal represents the proximity of the object 102 to the microwave element 108. The data signal defines the sub-microwave frequency.

Method 400 can also include a step of converting the data signal into a digital signal and a step of determining the proximity of the object 102 to the microwave element 108 as a function of the digital data signal. Alternatively, step 406 of generating the data signal may include mixing the frequency of the loading signal with the frequency of the reference signal. In addition, Method 400 can include the step of generating a reference signal such that the reference signal defines a frequency different from that of at least one microwave signal.

According to the embodiments described above, an effective and cost effective sensor assembly used to detect the proximity of an object is provided. In particular, according to the embodiments described herein, a sensor assembly for detecting the proximity of an object to a microwave element is provided. By including these sensor assemblies, stress monitoring (eg, rotating turbine shafts), binary switches or counters, dielectric monitors (eg, flooding into one or more fluids to measure electromagnetic response), strain gauges. (For example, bending a microwave element formed on a flexible substrate), and / or other suitable applications can be provided.

The sensor assembly embodiments described herein are compared to known eddy current sensors, magnetic pickup sensors or capacitive sensors currently used to detect the proximity of an object to a microwave element. , Can include a substantially extended detection range. Moreover, as compared to known eddy current sensors, magnetic pickup sensors and / or capacitive sensors, the positioning and / or position restrictions of the sensor assemblies described herein can be significantly relaxed. Moreover, because microwave elements have a faster frequency response when compared to known sensors, the sensor assemblies described herein may provide more accurate measurements than known sensor assemblies. it can.

This textual description includes the construction and use of any device or system by all skilled in the art, as well as the execution of any method incorporated, in order to disclose the invention, including the best mode. Some examples have been used to enable the practice of. The claims of the present invention are defined by the claims and can include other examples that come to mind for those skilled in the art. Such other examples may be unrealistically different from the written language of the claims, even if they have structural components that are not different from the written language of the claims. Even if they contain equivalent structural components, they are intended to be included in the claims.

100, 200, 300 sensor assembly 102, 202 objects 104, 204 signal generator 106, 206 coupler 108, 208 microwave emitter 110, 210 Electromagnetic field 112, 212 Processing module 114, 214 frequency mixer 116, 216 filters 118 signal processor 120 ADC converter 220 Reference signal generator 224 probe housing 326 power system 328 components 330 electrical device 332 load