AUTOMATIC DISTANCE MEASUREMENT IN THE FLOW CHANNEL

Description

[0001] The invention relates to a flow probe with a measuring sensor formed at a distal end of a shaft.

[0002] The invention further relates to a method for recording a location-dependent measured variable, wherein a measuring sensor is brought into a measuring range to be measured, which is defined by a boundary.

[0003] Such flow probes and methods are known and serve to record location-dependent measured variables. They are used, for example, for volume flow measurements in ducts, particularly flow channels. The duct geometry must be known and entered into the flow probe. The flow probe then specifies, for example, the positions at which the measured variable is to be determined using a measuring probe, in order to determine a measured variable profile or the measured variable at a specific position. The specified measuring points must then be manually traversed using the measuring probe, which can be mounted on a shaft. The user must manually check the shaft, for example, to determine whether the measuring position has been reached. This manual procedure is prone to errors.

[0004] From CN 215 573 150 U a portable Doppler flow velocity and current measuring device is known, which belongs to the field of flow measuring devices and comprises a mounting part and a measuring part, wherein the mounting part comprises a telescopic measuring rod, the measuring part comprises a laser width measuring sensor and a Doppler flow velocity and water depth sensor and the measuring part is arranged on the mounting part.

[0005] From DE 40 16 529 C1 a flow meter for open channels is known, with a flow probe which is immersed in the liquid and measures the flow velocity, which is attached to a positioning device and is movable under the control of a computer, wherein the flow probe is movable to numerous measuring points which are distributed in a measuring plane running transversely to the channel and whose flow velocities are measured and stored in the computer, the computer determines an average flow velocity vm of the measuring points and a reference flow velocity at a reference position in a calibration phase, and the computer sets the probe to the reference position in a measuring phase and calculates the current total flow velocity on the basis of the relationship between the average flow velocity (vm) and the reference flow velocity obtained in the calibration phase.

[0006] Similar devices are also known from US 6 973 842 B1 and US 2021 / 172816 A1.

[0007] The object of the invention is to improve the performance characteristics of such flow probes and methods and to reduce the susceptibility to errors in the determination of measured variables.

[0008] To achieve the stated object, the features of claim 1 are provided according to the invention. In particular, to achieve the stated object, in flow probes of the type described above, it is proposed according to the invention that at least one distance sensor is arranged at the distal end of the shaft.

[0009] In this way, the distance between the distal end of the shaft and, for example, surrounding channel and / or pipe walls can be determined. From this, the position of the distal end of the shaft can then be determined. Since the measuring probe is attached to the distal end of the shaft, its position is also known. This information can be used to automatically determine location-dependent measured variables. For example, a measured variable profile can be created by moving the distal end of the shaft to different positions. The user can also be informed as soon as the distal end has reached a predetermined measuring position. In this case, the distal end can extend over less than 50%, preferably less than 40% of the length of the shaft.The length of the shaft taken up by the distal end can be selected so that it reaches and / or exceeds a maximum extent, in particular of the cross-sectional area of ​​the measuring area to be examined.

[0010] According to the invention, the measuring sensor is configured to perform a measurement as a function of a distance measured by the at least one distance sensor. Alternatively or additionally, the at least one distance sensor can be configured to continuously measure a distance.

[0011] Thus, a measurement carried out by the measuring sensor can, for example, be triggered precisely when a specific position of the measuring sensor is reached within the area to be examined, for example a channel or pipe. A control unit can be provided which processes the data from the measuring sensor and / or the at least one distance sensor and / or the other sensors of the flow probe and / or triggers a measurement by the measuring sensor depending on a distance determined by means of the at least one distance sensor. By continuously measuring a distance, it is possible to carry out a continuous movement of the measuring sensor within the area to be examined, during which distances are continuously determined, and measurements are triggered when certain distances are reached.This is particularly advantageous when measurements need to be taken at specific intervals to comply with specific guidelines. Alternatively or additionally, measurements can be taken automatically and / or manually at specific intervals. The intervals or time intervals at which a measurement is to be triggered can, for example, be specified by a user.

[0012] According to the invention, an acceleration sensor is provided. The acceleration sensor is arranged at the distal end.

[0013] This allows the orientation of the probe in the gravitational field to be determined. Together with the measured values ​​of at least one distance sensor, a more precise position of the flow probe, in particular its distal end, can be determined, for example, in the form of a reliable height coordinate in a channel and / or pipe cross-section.

[0014] The location-dependent measured variable can be a flow velocity. This makes it possible, for example, to measure volume flow in ducts. For example, a volume flow profile can be determined across the cross-sectional area of ​​the duct.

[0015] In an advantageous embodiment, it can be provided that the distance sensor is a laser distance sensor.

[0016] This allows the distance to be determined optically. This is contactless and unaffected by, for example, air flow. The distance can also be determined with exceptional precision. The measured distance can be read electronically and further processed.

[0017] In an advantageous embodiment, it can be provided that at least two distance sensors, which are aligned in different directions, are arranged at the distal end.

[0018] This allows distances to be determined in multiple directions. This makes it possible to determine a two-dimensional position. For example, the position of the distal end within the cross-sectional area of ​​a channel can be determined.

[0019] In an advantageous embodiment, the flow probe can be provided with a signal generator for outputting a signal. The signal can be, for example, an optical and / or an acoustic signal. Additionally, it can be provided that the signal can be output as a function of a distance determined by the at least one distance sensor.

[0020] The signal generator can be, for example, a light element and / or a loudspeaker. This allows a user to be informed when the flow probe or measuring sensor has reached a predefined position. The user can then, for example, hold the flow probe in its current position to record a sufficiently long measurement. If the measurements are very short, the user can interpret the signals as a confirmation signal and move the flow probe further. Reaching a predefined position can be detected, for example, by means of the at least one distance sensor.

[0021] Alternatively or additionally, to achieve the stated object, the invention provides the features of the independent claim directed to a method for recording a location-dependent measured variable. In particular, to achieve the stated object, in methods of the type described above, the invention proposes that at least one distance sensor be brought into the measuring range with the measuring sensor, with which at least a distance between the measuring sensor and the boundary is recorded at the time of a measurement. The measurement whose time is relevant here is the measurement carried out using the measuring sensor. In addition, it can be provided that the distance is recorded continuously.

[0022] This allows for automatic and, in particular, continuous determination of the position of the measuring sensor. This position can be recorded, stored, and / or further processed together with a respective measured value.

[0023] According to the invention, an orientation in the gravitational field is determined using an acceleration sensor. This is the orientation of the measuring sensor and the at least one distance sensor. The acceleration sensor is fixedly connected to the measuring sensor and the at least one distance sensor.

[0024] Thus, measured values ​​of the acceleration sensor can be recorded, which, in particular in interaction with measured values ​​of the at least one distance sensor, increase the accuracy of the position determination of the flow probe, in particular its distal end or the measuring sensor.

[0025] In an advantageous embodiment, it can be provided that the orientation determined by the acceleration sensor is used to inform a user about the orientation. This can be information to the user about an impermissible orientation. Alternatively or additionally, it can be provided that the orientation is determined at the time of a measurement. Alternatively or additionally, it can be provided that measured values ​​from the measuring sensor are corrected for any deviation of the orientation from an ideal.

[0026] In this way, the user can be supported in aligning the flow probe, particularly in a measurement area that cannot be seen. The user can, for example, be informed if the measuring sensor is not optimally aligned and would produce unreliable data. The user can also be informed that the measuring sensor has reached a predetermined position, after which a measurement can be triggered automatically or manually. If the alignment is determined at the time of a measurement, this information can be saved for documentation purposes and / or used in a later process step. For example, measured values ​​from the measuring sensor can be corrected for any deviation from an ideal alignment. The alignment determined at the time of measurement can, for example, be used for this purpose.For example, a specific orientation of the measuring sensor relative to the prevailing flow in the measuring area can be defined as an ideal. Deviations of the actual orientation from the ideal can, for example, be correctable to a certain extent based on the actually determined orientation. If the deviation of the orientation from the ideal exceeds a sufficiently correctable level, the user can be actively informed to change the orientation of the measuring sensor.

[0027] In an advantageous embodiment, it can be provided that measured values ​​from the measuring sensor are output with at least one associated distance. Alternatively or additionally, it can be provided that measured values ​​from the measuring sensor are output with the associated orientation.

[0028] Thus, the information about the at least one distance or orientation, in particular the orientation already described, can be further processed electronically, for example. Measured values ​​can also be output with additional, associated parameters, such as the duration of a measurement. The measured values, in particular with associated distances, orientations, and / or durations, can be output, for example, to a storage unit for documentation.

[0029] In an advantageous embodiment, it can be provided that the measuring range is two-dimensional or three-dimensional.

[0030] This allows location-dependent measured values ​​to be determined at different positions within the measuring range. In particular, two- and / or three-dimensional measured value profiles can be determined.

[0031] In an advantageous embodiment, it can be provided that the measured variable is a flow velocity.

[0032] Thus, the aforementioned advantages can be utilized in flow velocity measurements. In particular, one-, two-, and / or three-dimensional flow profiles can be created. This also enables automatic, spatially resolved volume flow measurement in ducts.

[0033] In an advantageous embodiment, it can be provided that the measuring sensor is introduced into the measuring area through an opening in the boundary that is preferably matched to a size of the measuring sensor.

[0034] This allows the opening through which the measuring sensor is inserted into the measuring area to be as small and / or large as necessary. The opening can be selected to be just large enough so that, after the measuring sensor has been inserted, it is sealed off from the outside just enough to allow the sensor to be moved across the measuring area. This reduces and / or eliminates external interference with the measuring area and the measurement results.

[0035] According to the invention, a geometric variable, which is the shape and size of the measuring area, is determined from measured values ​​of the at least one distance sensor and the acceleration sensor. Furthermore, a measuring location is determined from the measured values.

[0036] This makes it possible to measure the measuring range. For example, the shape and / or size of the measuring range can be determined even if a channel and / or pipe to be examined has an internal dimension that differs from an external dimension, for example due to existing insulation. Dimensions that can be determined using the at least one distance sensor and / or the acceleration sensor can also be predetermined for different measuring ranges, so that a measuring location can be determined. This can, for example, be a specific access point into a channel and / or a pipe. Alternatively or additionally, determinable dimensions outside the measuring range can also be used, which are determined, for example, when the flow probe is inserted into the measuring range.

[0037] According to the invention, a measurement is performed by the measuring sensor as a function of a distance determined by the at least one distance sensor. Furthermore, a measurement is performed by the measuring sensor as a function of a determined position of the measuring sensor in the measuring range.

[0038] A measurement can therefore be triggered by the measuring sensor exactly when the measured distance corresponds to a previously determined distance. A measurement by the measuring sensor can also be triggered exactly when a determined position corresponds to a previously determined position. Such previously determined positions and distances can, for example, result from guidelines according to which measured values ​​are to be determined at specific distances or positions. It is also possible to first determine a geometry of the measuring area using the at least one distance sensor, in particular by manually moving the distance sensor through the measuring area, for example, and then to specify the distances or positions at which a measurement is to be taken. Alternatively or additionally, measurements can be triggered at specific time intervals. The measurements can, for example, be carried out using the associated measured at least one distance ordetermined position of the measuring sensor or with the associated measuring duration.

[0039] According to the invention, it is provided that a flow probe according to the invention is used in the method.

[0040] Thus, the advantages of a flow probe according to the invention can be utilized in methods according to the invention.

[0041] According to the invention, the coverage of the measuring range is determined by the flow probe. In addition, the measured values ​​of the measuring sensor are corrected by the coverage of the measuring range.

[0042] Inserting the flow probe into the measuring area is associated with the flow probe covering the measuring area. This covering can, for example, be the projection of the outer dimensions of the flow probe onto the cross-sectional area of ​​the measuring area, which is preferably orthogonal to the flow direction. This covering can lead to flow changes, particularly in comparatively small measuring areas, for example in channels and / or pipes with a small cross-sectional area. This can lead to deviations of the determined measured values ​​from the existing flow conditions and / or increase them. The determination of the coverage of the measuring area by the flow probe, which according to the invention is carried out on the basis of the measured values ​​of the at least one distance sensor and the acceleration sensor, serves to correct the measured values ​​of the measuring sensor in order to produce more precise measurement results.

[0043] In an advantageous embodiment of a flow probe according to the invention, it can be provided that the flow probe is designed to carry out a method according to the invention.

[0044] Thus, the advantages of the inventive method can be utilized with the inventive measuring devices.

[0045] The invention will now be described in more detail using an exemplary embodiment, but is not limited to the exemplary embodiment. Further exemplary embodiments arise from combining the features of one or more claims with one another and / or with one or more features of the exemplary embodiment.

[0046] It shows: Figure 1 shows a schematic representation of a flow probe according to the invention.

[0047] Figure 1shows a schematic representation of a measuring device 1 designed as a flow probe 11 according to the invention, with a measuring sensor 2 formed at a distal end 3 of a shaft 4. The shaft 4 of the measuring device 1 is inserted, with its distal end 3 leading, into a measuring area 6 through an opening 5 matched to a size of the measuring sensor 2. Distance sensors 7, 8, 9 are also formed at the distal end 3 and oriented in different directions. The measuring sensor 2 is a volume flow sensor 10. The measured variable is a flow velocity. The distance sensors 7, 8, 9, which are laser distance sensors, determine the distances 12, 13, 14 of the distal end 3 to the boundary 15 of the measuring area 6. Thus, the determined distances or a position of the distal end 3 of the shaft 4 and thus also of the measuring sensor 2 calculated therefrom can be recorded and / or output together with the respective measured values.

[0048] In this case, the measuring range 6 is also multi-dimensional. Furthermore, an acceleration sensor 16 is arranged at the distal end 3. By means of the measuring device 1, it is possible to perform a measurement as a function of a distance 12, 13, 14 measured with the at least one distance sensor 7, 8, 9. The at least one distance sensor 7, 8, 9 can be configured to continuously measure a distance 12, 13, 14. The measuring device 1 has a signal generator (not shown in detail) for outputting an optical and acoustic signal, wherein the signal can be output as a function of a distance 12, 13, 14 determined with the at least one distance sensor 7, 8, 9. The signal generator is a combination of a lighting element and a loudspeaker (not shown in detail).

[0049] The measuring device 1 shown is suitable for carrying out a method according to the invention. At least one distance sensor 7, 8, 9 is introduced into the two-dimensional or three-dimensional measuring area 6 with the measuring sensor 2. The measured variable is a flow velocity. The distance sensors 7, 8, 9 record at least one distance 12, 13, 14 of the measuring sensor 2 to the boundary 15 at the time of the measurement, and even continuously. The orientation of the measuring sensor 2 and the distance sensors 7, 8, 9 in the gravitational field is determined by means of the acceleration sensor 16, which is fixedly connected to the measuring sensor 2 and the distance sensors 7, 8, 9. The orientation determined by means of the acceleration sensor 16 is used to inform a user about the orientation, for example, an impermissible orientation, and is determined at the time of a measurement.Measured values ​​from the measuring sensor 2 are corrected for any deviation of the alignment from an ideal and output with associated distances 12, 13, 14 and associated alignment. From measured values ​​from the at least one distance sensor 7, 8, 9 and the acceleration sensor 16, a geometric variable, namely the shape and size of the measuring area 6, as well as a measuring location, are determined. The measurement by the measuring sensor 2 is carried out as a function of a distance 12, 13, 14 recorded by the at least one distance sensor 7, 8, 9 and as a function of a determined position of the measuring sensor 2 in the measuring area 6. An optical and acoustic signal is output if the distance 12, 13, 14 determined by the at least one distance sensor 7, 8, 9 corresponds to a previously defined distance and if the determined position of the measuring sensor 2 corresponds to a previously defined position.The measured values ​​of the measuring sensor 2 are also corrected by an overlap of the measuring range 6 by the measuring device 1.

[0050] It is therefore proposed that in measuring devices 1 with measuring sensors 2 at a distal end 3 of a shaft 4, at least one distance sensor 7, 8, 9 and / or an acceleration sensor 16 be formed at this distal end 3 in order to enable automatic distance measurement and / or determination of the position and / or orientation of the measuring sensor 2 within a measuring range 6 and thus the recording of spatially resolved measured values ​​(cf. Fig. 1 ). List of reference symbols

[0051] 1Measuring device 2Measuring sensor 3Distal end 4Shaft 5Opening 6Measuring range 7Distance sensor 8Distance sensor 9Distance sensor 10Volume flow sensor 11Flow probe 12Distance 13Distance 14Distance 15Limitation 16Acceleration sensor

Claims

1. Flow probe (11), having a measuring sensor (2) formed at a distal end (3) of a shaft (4), wherein at least one distance sensor (7, 8, 9) is arranged at the distal end (3), characterized in that an acceleration sensor (16) is provided and arranged at the distal end (3), in that a geometric variable, the shape and the size of a measuring region (6) and a measuring location of the measuring sensor in a measuring region (6) is determined, in that the measuring sensor (2) is designed to perform a measurement as a function of a distance (12, 13, 14) measured with the at least one distance sensor (7, 8, 9) and as a function of a determined position of the measuring sensor (2) in the measuring region (6), in that an overlap of the measuring region (6) by the flow probe (11) is determined on the basis of the measured values of the at least one distance sensor (7, 8, 9) and the acceleration sensor (16), and in that measured values of the measuring sensor (2) are corrected by the overlap of the measuring region (6).

2. Flow probe (11) according to claim 1, characterized in that the at least one distance sensor (7, 8, 9) is designed for continuous measurement of a distance (12, 13, 14).

3. Flow probe (11) according to one of the preceding claims, characterized in that the distance sensor (7, 8, 9) is a laser distance sensor.

4. Flow probe (11) according to one of the preceding claims, characterized in that at least two, preferably three, distance sensors (7, 8, 9) which are aligned in different directions are arranged at the distal end (3).

5. Flow probe (11) according to one of the preceding claims, characterized in that the flow probe (11) has a signal transmitter for outputting a preferably optical and / or acoustic signal, in particular wherein the signal can be output at a predetermined distance (12, 13, 14) determined by the at least one distance sensor (7, 8, 9).

6. Method for recording a location-dependent measured variable, wherein a flow probe according to one of claims 1 to 5 is used, wherein the measuring sensor (2) is brought into a measuring region (6) to be measured, defined by a boundary (15), wherein at least one distance sensor (7, 8, 9) is brought into the measuring region (6), with which at least one distance (12, 13, 14) of the measuring sensor (2) to the boundary (15) is recorded at the time of a measurement, in particular continuously, characterized in that an alignment of the measuring sensor (2) and the at least one distance sensor (7, 8, 9) in the gravitational field is determined by means of an acceleration sensor (16) connected in a fixed manner to the measuring sensor (2) and the at least one distance sensor (7, 8, 9), in that a geometric variable, the shape and the size of the measuring region (6), and a measuring location of the measuring sensor (2) in the measuring region (6) are determined from measured values of the at least one distance sensor (7, 8, 9) and the acceleration sensor (16), in that a measurement is performed as a function of a distance (12, 13, 14) measured with the at least one distance sensor (7, 8, 9) and as a function of a determined position of the measuring sensor (2) in the measuring region (6), in that an overlap of the measuring region (6) by the flow probe (11) is determined on the basis of the measured values of the at least one distance sensor (7, 8, 9) and the acceleration sensor (16), and in that the measured values of the measuring sensor (2) are corrected by the overlap of the measuring region (6).

7. Method according to claim 6, characterized in that the alignment determined by means of the acceleration sensor (16) is used to inform a user about the alignment, in particular about an impermissible alignment, and / or is determined at the time of a measurement, and / or in that measured values of the measuring sensor (2) are corrected by a deviation of the alignment from an ideal.

8. Method according to one of claims 6 or 7, characterized in that measured values of the measuring sensor (2) are output with at least one associated distance (12, 13, 14) and / or associated orientation, and / or in that the measuring region (6) is two-dimensional or three-dimensional, and / or in that the measured variable is a flow velocity.

9. Method according to one of claims 6 to 8, characterized in that the measuring sensor (2) is introduced into the measuring region (6) through an opening (5) in the boundary (15), which is preferably adapted to a size of the measuring sensor (2).

10. Method according to one of claims 6 to 9, characterized in that a preferably optical and / or acoustic signal is emitted when the distance (12, 13, 14) determined by means of the at least one distance sensor (7, 8, 9) corresponds to a previously defined distance and / or when the determined position of the measuring sensor (2) corresponds to a previously defined position.