Transducer inspection device and inspection method

Abstract

To easily inspect a vibrator of a sounding device and a detector.SOLUTION: A vibrator inspection device includes: a wave transmitting / receiving unit 2 as means for transmitting and receiving ultrasonic waves while sweeping the transmitting / receiving frequency over a predetermined frequency range and converting the waves into electrical signals; and an inspection calculation unit 5 as means for processing the electrical signal to calculate an average value of echo signal strength and determining the soundness of an ultrasonic vibrator in the transmitting / receiving unit 2 for transmitting and receiving ultrasonic waves based on whether there is a peak of the average value of the echo signal strength in the predetermined frequency range, where the average value of the echo signal strength is the average value of the echo signal strength in the predetermined range including the oscillation line.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an inspection device and method for transducers, and more specifically, to a technique for inspecting transducers of depth sounders and detectors that measure water depth and detect underwater targets based on ultrasonic waves transmitted into water and reflected by the water bottom or targets. [Background technology]

[0002] Conventionally, as a technology for performing underwater detection based on reflected waves of ultrasonic waves transmitted into the water, an underwater detection device is known which includes a first generating means for generating a first transmission signal, a second generating means for generating a second transmission signal having a longer pulse width than the first transmission signal, an output means for outputting the transmission signals generated by the first and second generating means to a transmitter / receiver which transmits ultrasonic waves based on the transmission signal into the water and receives the reflected waves reflected in the water and converts them into a received signal, an underwater detection means for detecting fish or water depth based on a first received signal related to the first transmission signal output from the transmitter / receiver, and a bottom sediment discrimination means for discriminating the seabed sediment based on a second received signal related to the second transmission signal output from the transmitter / receiver (Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2012-225651 A Summary of the Invention [Problem to be solved by the invention]

[0004] Incidentally, the transducers of depth sounders and detectors installed on ships need to be inspected and cleaned periodically because their characteristics change mainly due to external factors (specifically, long-term pressurization by water pressure, impacts from punching in rough weather, adhesion of marine organisms, etc.) and aging deterioration. If a significant performance degradation is observed, they must be replaced. Conventionally, an engineer in charge of data acquisition visits the target ship equipped with a depth sounder or detector and measures the characteristics of the transducer using measuring instruments such as SWR meters, and an engineer in charge of data analysis verifies the results to determine the soundness of the transducer. In other words, measuring instruments such as SWR meters and engineers are required to check the performance of the transducer, which is a problem in that it takes a lot of effort, time, and money, and it is necessary to adjust the timing of the visit to the ship. In addition, since the transducers of depth sounders and detectors are installed on the bottom of the ship, there is a problem that it is not possible to add a separate receiver like a performance monitor for radar.

[0005] SUMMARY OF THE PRESENT EMBODIMENT An object of the present invention is to provide a transducer inspection device and inspection method that can easily inspect the transducers of depth sounders and detectors. [Means for solving the problem]

[0006] In order to solve the above problems, the present invention provides an inspection device for a transducer, which is configured to irradiate ultrasonic waves while sweeping a transmission / reception frequency over a predetermined frequency range. Into the water As the waves are transmitted To a means for receiving the ultrasonic waves and converting them into an electric signal, a means for processing the electric signal to calculate an average value of the echo signal strength, and a means for detecting the ultrasonic waves based on whether or not a peak of the average value of the echo signal strength exists within the predetermined frequency range. Into the water and a means for determining the soundness of the transducer that transmits and receives the waves, wherein the average value of the echo signal strength is the average value of the echo signal strength in a predetermined range including the oscillation line. the law of nature , The oscillation line corresponds to the leakage of the self-transmitted pulse. It is characterized by:

[0007] In addition, the method for inspecting a transducer according to the present invention includes irradiating ultrasonic waves while sweeping a transmission / reception frequency over a predetermined frequency range. Into the water As the waves are transmitted To A process of receiving the ultrasonic waves and converting them into an electrical signal, a process of processing the electrical signal to calculate an average value of the echo signal strength, and a process of detecting the ultrasonic waves based on whether or not a peak of the average value of the echo signal strength exists within the predetermined frequency range. Into the water and a process for determining the soundness of the transducer that transmits and receives the waves, wherein the average value of the echo signal strength is an average value of the echo signal strength in a predetermined range including the oscillation line. the law of nature , The oscillation line corresponds to the leakage of the self-transmitted pulse. It is characterized by:

[0008] In the vibrator inspection device and the vibrator inspection method according to the present invention, a first frequency flw on the lower limit side and a second frequency fup on the upper limit side of the predetermined frequency range may be determined by the following Formulas 1A to 1C. (Math 1A) fwd=f0 / Q (Math 1B) flw=f0-fwd / 2 (Math 1C) fup=f0+fwd / 2 where fwd is the width of the frequency range over which the transmission and reception frequencies are swept. f0: Resonant frequency of the oscillator Q: Q value of the transducer

[0009] The transducer inspection device and transducer inspection method of the present invention may be configured so that the maximum value of the average value of the echo signal intensity is Imax, the average value of the echo signal intensity at the first frequency flw is Iflw, and the average value of the echo signal intensity at the second frequency fup is Ifup, and an intensity threshold value is Ti, and if the following condition 1 is satisfied, it is determined that the transducer is normal, and if the following condition 1 is not satisfied, it is determined that an abnormality has occurred in the transducer, and the intensity threshold value Ti is set to any value in the range of 5 to 7 dB. (Condition 1) Imax-Iflw≧Ti and Imax-Ifup≧Ti Effect of the Invention

[0010] According to the transducer inspection device and transducer inspection method of the present invention, the depth sounder or detector itself can execute various processes related to the transducer inspection and determine the soundness of the transducer, so there is no need for an engineer or technician to visit the ship on which the depth sounder or detector is installed, and it is possible to reduce and shorten the effort, time, and cost required for checking the performance of the transducer, and it becomes possible to easily inspect the transducer of the depth sounder or detector. Also, since the depth sounder or detector itself can determine the soundness of the transducer, it becomes possible to instantly check the soundness of the transducer, and it becomes possible to improve the usefulness of the transducer inspection method.

[0011] In the transducer inspection device and transducer inspection method of the present invention, when the frequency range for sweeping the transmission and reception frequencies is determined based on the transducer's resonant frequency and Q value, it becomes possible to appropriately set the search / detection range for the peak of the average echo signal intensity, thereby improving the reliability of the transducer inspection method.

[0012] In the vibrator inspection device and vibrator inspection method of the present invention, if the health of the vibrator is determined based on whether or not the above condition 1 is satisfied between the maximum value Imax of the average echo signal intensity, the average value Iflw of the echo signal intensity at the first frequency flw, and the intensity threshold value Ti, and between the maximum value Imax of the average echo signal intensity, the average value Ifup of the echo signal intensity at the second frequency fup, and the intensity threshold value Ti, it becomes possible to appropriately determine the health of the vibrator, and ultimately to improve the reliability of the vibrator inspection method. [Brief description of the drawings]

[0013] [Figure 1] 1 is a functional block diagram showing a schematic configuration of an inspection device for a transducer according to an embodiment of the present invention; [Diagram 2] 4 is a flowchart showing a process of a method for inspecting a transducer according to an embodiment of the present invention; [Diagram 3] 1 is a diagram illustrating the relationship between a resonant frequency and the width of a frequency band related to a Q value. [Figure 4] 10 is a schematic diagram showing an example of the relationship between the fluctuation of the average value of the echo signal intensity in the oscillation line range and the judgment of the soundness of the ultrasonic transducer of the transmitting and receiving unit. FIG. [Diagram 5] 10A and 10B are diagrams for explaining a procedure (determination method 2) for determining the soundness of an ultrasonic transducer of a transmitting and receiving unit. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] The present invention will be described below based on the illustrated embodiments. Fig. 1 is a functional block diagram showing a schematic configuration of an inspection device 1 for a vibrator according to the embodiment of the present invention. Fig. 2 is a flow diagram showing a processing procedure of an inspection method for a vibrator according to the embodiment of the present invention.

[0015] The transducer inspection device 1 is a mechanism for inspecting transducers of depth sounders, detectors, sonars, etc. (hereinafter referred to as "depth sounders, etc.") which measure water depth and detect underwater targets based on ultrasonic waves transmitted into the water and reflected by the water bottom or targets (e.g., schools of fish), and is configured by adding functions to the depth sounders, etc. to perform various processes related to the inspection of transducers of the depth sounders, etc.

[0016] For this reason, the transducer inspection device 1 is equipped with a mechanism for measuring water depth and detecting underwater targets based on the reflected waves of ultrasonic waves transmitted into the water and reflected by the water bottom or targets (i.e., a mechanism as a general depth sounder, etc.), and a mechanism for performing various processes related to transducer inspection (i.e., a mechanism unique to this invention), and in this embodiment has a transmitter / receiver unit 2, a transmitter / receiver unit 3, a processing unit 4, an inspection calculation unit 5, a memory unit 6, a display unit 7, and an output unit 8.

[0017] Taking the above into consideration, the following will mainly describe the characteristic configurations of the present invention, and will omit a description of configurations that are similar to conventional configurations for functioning as general depth sounders, etc., and that are unrelated to the characteristic configurations of the present invention.

[0018] The wave transmitting / receiving unit 2 has one or more ultrasonic transducers (not shown) as a wave transmitting / receiving element, and has the function of transmitting / transmitting and receiving / receiving ultrasonic waves. The wave transmitting / receiving unit 2 is disposed, for example, on the bottom of a ship, transmits / transmits ultrasonic waves into water, and receives / receives ultrasonic waves including waves reflected by targets in the water.

[0019] The ultrasonic transducer of the transmitting / receiving unit 2 converts an electrical signal supplied from the outside into ultrasonic waves and transmits / sends the ultrasonic waves into the water as transmitted waves, and also receives / receives ultrasonic waves, including reflected waves that are reflected off an underwater target and return, as received waves, and converts the received waves into electrical signals and outputs them.

[0020] The transmitting / receiving unit 3 includes a switching circuit 31, a transmitting circuit 32, a receiving circuit 33, a detection circuit , and an A / D converter .

[0021] The switching circuit 31 is interposed between the ultrasonic transducer of the wave transmitting / receiving unit 2 and the transmission circuit 32 and reception circuit 33, and has a function of switching the operation of the wave transmitting / receiving unit 2 and the transmitting / receiving unit 3 between transmission and reception.

[0022] The transmission circuit 32 is provided corresponding to each ultrasonic transducer, and is controlled by the processing unit 4 to generate ultrasonic waves / transmission waves transmitted from the wave transmitting / receiving unit 2. In other words, the transmission circuit 32 generates a drive signal (in other words, a transmission The RC-200 generates and outputs a transmission trigger pulse signal (transmission signal, transmission trigger pulse signal).

[0023] The drive signal output from the transmission circuit 32 is supplied to the wave transmitting and receiving unit 2 via the switching circuit 31 when the switching circuit 31 switches to a connection in which a signal is sent from the transmission circuit 32 to the wave transmitting and receiving unit 2 .

[0024] The ultrasonic transducer of the wave transmitting / receiving unit 2 is driven by the drive signal output from the transmission circuit 32, and ultrasonic waves are transmitted into the water. The ultrasonic waves transmitted from the wave transmitting / receiving unit 2 are reflected by the bottom of the water or a target and returned. The reflected waves include ultrasonic waves received by the wave transmitting / receiving unit 2, converted into electrical signals, and output.

[0025] The electrical signal output from the wave transmitting / receiving unit 2 is transmitted to the receiving circuit 33 via the switching circuit 31 by the switching circuit 31 switching to a connection that sends a signal from the wave transmitting / receiving unit 2 to the receiving circuit 33.

[0026] The receiving circuit 33 has a function of generating a receiving signal. Specifically, the receiving circuit 33 receives an input of an electrical signal output from the wave transmitting / receiving unit 2, amplifies the electrical signal, limits the band of the electrical signal, removes unnecessary frequency components (i.e., noise), and outputs the signal as a receiving signal.

[0027] The detection circuit 34 receives the received signal output from the receiving circuit 33, performs detection processing on the received signal to detect envelope data of the received signal, and outputs amplitude information as echo signal intensity (an analog signal). Since the detection processing itself is a well-known technique, a detailed description will be omitted here.

[0028] An A / D converter 35 (Analog-to-Digital converter) receives the analog echo signal intensity output from the detection circuit 34, samples the analog echo signal intensity at a predetermined time interval, performs analog-to-digital conversion processing, and outputs the echo signal intensity converted into a digital signal.

[0029] The processing unit 4 has the function of coordinating and controlling each part that constitutes the oscillator inspection apparatus 1, and may be configured, for example, to include a central processing unit (CPU: short for Central Processing Unit) or an FPGA (short for Field Programmable Gate Array).

[0030] The processing unit 4 has a sampling circuit 41 and also includes an inspection calculation unit 5 .

[0031] The sampling circuit 41 receives an input of echo signal intensities converted into digital signals output from the transmitting / receiving unit 3 (specifically, the A / D converter 35), and records and accumulates in the memory unit 6, among the echo signal intensities, those to be used for inspecting the transducer, based on a control signal from the inspection calculation unit 5 (specifically, the sampling task 52).

[0032] In addition, the detection circuit 34 and A / D converter 35 of the transceiver unit 3 and the sampling circuit 41 of the processing unit 4 may be configured using a DSP (abbreviation for Digital Signal Processor) or a PLD (abbreviation for Programmable Logic Device) such as an FPGA (abbreviation for Field Programmable Gate Array).

[0033] The inspection calculation unit 5 is a task group for executing various processes related to the inspection of the transducer, which is realized by, for example, executing a predetermined program stored in the memory unit 6 by the processing unit 4. Specifically, the ... realized by, for example, executing a predetermined program stored in the memory unit 6 by the processing unit 4. Specifically, the inspection calculation unit 5 is realized by, for example, executing a predetermined program stored in the memory unit 6 by the processing unit 4. Based on this, the ultrasonic transducer of the wave transmitting / receiving unit 2 is inspected. The inspection calculation unit 5 has a frequency control task 51, a sampling task 52, a calculation task 53, and a judgment task .

[0034] The memory unit 6 has the function of serving as a memory area for storing various information, programs, data, etc., and the function of serving as a working area for temporarily storing data and information generated when the processing unit 4 executes calculations related to the inspection of the transducer, and is composed of storage devices and memory elements such as ROM (short for Read Only Memory), a hard disk (HDD: short for Hard Disk Drive), and RAM (short for Random Access Memory).

[0035] The display unit 7 has a function of displaying the results of the transducer inspection performed by the inspection and calculation unit 5, and is configured by, for example, a liquid crystal display.

[0036] The transducer inspection device 1 according to the embodiment emits ultrasonic waves while sweeping the transmission and reception frequency over a predetermined frequency range. Into the water As the waves are transmitted To a transmitting / receiving unit 2 as a means for receiving waves and converting them into an electric signal; a means for processing the electric signal to calculate an average value of the echo signal strength and for detecting an ultrasonic wave based on whether or not a peak of the average value of the echo signal strength exists within the predetermined frequency range; Into the water The ultrasonic transducer includes an inspection and calculation unit 5 as a means for determining the soundness of the ultrasonic transducer of the transmitting and receiving unit 2, which transmits and receives waves, and the average value of the echo signal intensity is the average value of the echo signal intensity in a specified range including the oscillation line.

[0037] In addition, the method for inspecting a transducer according to the embodiment includes irradiating ultrasonic waves while sweeping a transmission / reception frequency over a predetermined frequency range. Into the water As the waves are transmitted To The process includes a process of receiving the echo and converting it into an electric signal (steps S1 to S4), a process of processing the electric signal to calculate an average value of the echo signal intensity (step S5), and a process of detecting an ultrasonic wave based on whether or not a peak of the average value of the echo signal intensity exists in the predetermined frequency range. Into the water The method further includes a process (step S6) for determining the soundness of the ultrasonic transducer of the transmitting / receiving unit 2 that transmits and receives waves, and the average value of the echo signal intensity is the average value of the echo signal intensity in a predetermined range including the oscillation line.

[0038] The frequency control task 51 of the inspection calculation unit 5 issues a command to the transmission circuit 32 (specifically, each of the transmission circuits provided corresponding to each ultrasonic transducer) to control the transmission frequency while causing the transmission circuit 32 to generate a drive signal, and also issues a command to the reception circuit 33 to control the reception frequency of the reception circuit 33 to match the transmission frequency. Note that when the wave transmitting / receiving unit 2 has a plurality of ultrasonic transducers, the inspection of the transducers is repeatedly performed for each ultrasonic transducer.

[0039] The frequency control task 51 controls the frequency of the ultrasonic pulse transmitted from the ultrasonic transducer of the transmitting and receiving unit 2 and the frequency band of the ultrasonic waves received by the ultrasonic transducer of the transmitting and receiving unit 2 so as to sweep over a predetermined frequency range (step S1). The width fwd of the predetermined frequency range when the frequency control task 51 sweeps the transmission and reception frequency is determined based on the resonance frequency f0 and the Q value of the ultrasonic transducer of the transmitting and receiving unit 2.

[0040] Here, the relationship in Equation 2 below holds between the Q value, which is an amount representing the sharpness of mechanical resonance, the resonance frequency f0, and the width of the frequency band at the point -3 dB from the peak value, "f2-f1" (see Figure 3). Note that the point -3 dB from the peak value is the position where the amplitude is 1 / √(2) and the energy is 1 / 2 with respect to the peak (i.e., the level at the resonance frequency f0). (Equation 2) Q=f0 / (f2-f1)

[0041] Although the resonant frequency f0 and the Q value to which the present invention can be applied are not limited to specific values, as an example, the resonant frequency f0 may be 200 kHz and the Q value may be about 16, or the resonant frequency f0 may be 50 kHz and the Q value may be about 38. can be.

[0042] 3 and the relationship between the Q value, the resonant frequency f0, and the frequency band width "f2-f1" shown in Equation 2 above, it is believed that there is one clear peak (i.e., a peak of a unimodal distribution) in the range from frequency f1 to frequency f2 in the level of the ultrasound transmitted from the ultrasound transducer of the transmitting / receiving unit 2, and in turn in the level of the ultrasound received by the ultrasound transducer of the transmitting / receiving unit 2. Therefore, the present invention judges the soundness of the ultrasound transducer of the transmitting / receiving unit 2 based on whether or not there is a peak of the echo signal intensity (a peak of a unimodal distribution) in the range from frequency f1 to frequency f2.

[0043] Specifically, if there is a peak of echo signal intensity (peak of a unimodal distribution) that satisfies a specified condition in the range from frequency f1 to frequency f2, it is determined that the ultrasonic transducer of the transmitter-receiver unit 2 is normal, and if there is no peak of echo signal intensity that satisfies the specified condition or if there is a valley of echo signal intensity that satisfies the specified condition, it is determined that an abnormality has occurred in the ultrasonic transducer of the transmitter-receiver unit 2.

[0044] In consideration of the above, the frequency control task 51 controls the transmission circuit 32 and the reception circuit 33 to sweep the transmission and reception frequencies in the range from the first frequency flw (in other words, the lower limit frequency) to the second frequency fup (in other words, the upper limit frequency). The first frequency flw and the second frequency fup are determined according to the following formulas 3A to 3C. (Math 3A) fwd=f0 / Q (Math 3B) flw=f0-fwd / 2 (Math 3C) fup=f0+fwd / 2 where fwd is the width of the frequency band corresponding to f1 to f2 in FIG. 3, The width of the frequency range over which the transmit and receive frequencies are swept f0: Resonance frequency of the ultrasonic transducer of the transmitting / receiving unit 2 Q: Q value of the ultrasonic transducer of the transmitting / receiving unit 2 flw: The first frequency in the frequency range over which the transmit and receive frequencies are swept. fup: Second frequency in the frequency range over which the transmit and receive frequencies are swept Note that the first frequency flw is smaller than the second frequency fup.

[0045] As mentioned above, the point -3 dB from the peak value has an amplitude of 1 / √(2) of the peak, so if the transmission and reception frequency is changed in the range from flw to fup, the transmission sensitivity and reception sensitivity will both be -3 dB, resulting in a total of -6 dB for transmission and reception, which is a calculation that fluctuates to the extent that the echo signal strength is halved (i.e., 1 / √(2) / √(2) = 0.5).

[0046] In addition, since the resonant frequency f0 of the ultrasonic transducer may vary, a margin of, for example, about 1 to 3 kHz may be subtracted or added to each of the first frequency flw and the second frequency fup calculated by the above formulas 3A to 3C, and then the final first frequency flw and the second frequency fup may be set.

[0047] The frequency change amount Δf (i.e., the frequency change pitch) when the frequency control task 51 sweeps the transmission and reception frequencies is not limited to a specific value, but is appropriately set to an appropriate value, for example, taking into consideration the total time required for inspecting the transducer while sweeping the transmission and reception frequencies in the range from the first frequency flw to the second frequency fup. Specifically, the frequency change amount Δf may be set to any value within the range of about 0.1 to 1.0 kHz.

[0048] The ultrasonic transducer of the transmitting / receiving unit 2 is driven by a drive signal output from the transmission circuit 32 under the control of the frequency control task 51, and ultrasonic waves are transmitted into the water. The ultrasonic waves are received by the wave transmitting / receiving unit 2, converted into an electric signal, and output (step S2).

[0049] The sampling task 52 issues a command to the sampling circuit 41, and while the transmitting / receiving unit 2 is transmitting and receiving ultrasonic waves for inspecting the transducer based on the command from the frequency control task 51, the echo signal intensity output from the A / D converter 35 and transmitted to the sampling circuit 41 is recorded and accumulated in the memory unit 6 (step S3).

[0050] In other words, the sampling task 52 records and accumulates in the memory unit 6 the echo signal intensity while transmitting and receiving ultrasonic waves at each frequency changed by the frequency change amount Δf from the first frequency flw to the second frequency fup based on the command from the frequency control task 51 (step S4: No), and when the sweep of the transmission and reception frequency from the first frequency flw to the second frequency fup is completed (step S4: Yes), the processing procedure for inspecting the transducer proceeds to the processing of step S5.

[0051] By the operation of the sampling task 52, the echo signal intensity at each frequency from the first frequency flw to the second frequency fup, which is changed from the first frequency flw by the frequency change amount Δf, is recorded and accumulated in the memory unit 6.

[0052] The calculation task 53 calculates the average value of the echo signal intensities in a predetermined range including the oscillation line (called the "oscillation line range") (step S5).

[0053] The oscillation line corresponds to the portion corresponding to the interference of the self-transmitted pulse, and it is understood that the echo signal strength in the oscillation line range corresponds mainly to the signal strength of the interference of the self-transmitted pulse. In other words, in the normal procedure for measuring water depth or detecting underwater targets, the reflected waves reflected by the underwater target are received and signal processed, whereas in the inspection of the transducer according to the present invention, the interference of the self-transmitted pulse is received and signal processed to determine the soundness of the ultrasonic transducer of the transmitting and receiving unit 2.

[0054] Specifically, the calculation task 53 reads the echo signal strength at each frequency recorded and stored in the storage unit 6, and calculates the average value of the echo signal strength in the oscillation line range for each of the frequencies.

[0055] The lower limit and upper limit of the oscillation line range (specifically, the water depth) are not limited to specific values, but are appropriately set to appropriate values, taking into consideration that the peak of the average value of the echo signal intensity can be clearly seen in the range from the first frequency flw to the second frequency fup when the ultrasonic transducer is normal. Specifically, for example, the lower limit of the oscillation line range may be set to any value in the range of about 0 to 1.0 m, and the upper limit of the oscillation line range may be set to any value in the range of about 0.5 to 1.0 m (however, the lower limit value≦the upper limit value). Note that the lower limit value and the upper limit value may be set to the same value, and the echo signal intensity at a specific water depth may be used as the average value of the echo signal intensity in the oscillation line range.

[0056] In addition, data from one transmission and reception by the transmitter / receiver unit 2 may be used to find the average value of the echo signal intensity in the oscillation line range, or data from multiple transmissions and receptions by the transmitter / receiver unit 2 may be used to find the average value of the echo signal intensity in the oscillation line range.

[0057] Here, the calculation task 53 uses the echo signal intensity in the oscillation line range as described above, and it is assumed that the echo signal intensity in the oscillation line range is usually strong. Before the transducer inspection procedure is started, the transmission power may be adjusted (specifically, reduced) so that the signal strength (specifically, the average value) is below a saturation level (step S0).

[0058] Specifically, before the transmitter / receiver unit 2 transmits and receives ultrasonic waves for inspecting the transducer (i.e., before step S1), in order to adjust the transmission output, the transmitter / receiver unit 2 transmits and receives ultrasonic waves while the transmission / reception frequency is fixed to the resonant frequency f0 and the average value of the echo signal intensity in the oscillation line range is calculated by calculation task 53.

[0059] Then, when the average value of the echo signal intensity in the oscillation line range reaches or exceeds the saturation level, the PWM (short for Pulse Width Modulation) duty ratio is reduced, and the transmission and reception of ultrasonic waves by the transmitting / receiving unit 2 is repeated (in other words, repeatedly) performed while maintaining the resonant frequency f0, and the calculation task 53 is repeated (in other words, repeatedly) performed to calculate the average value of the echo signal intensity in the oscillation line range.

[0060] Then, when the average value of the echo signal intensity in the oscillation line range falls below the saturation level, the PWM duty ratio at that time is fixed (step S0), and ultrasonic waves are transmitted and received by the transmitter / receiver unit 2 as a procedure for inspecting the transducer (step S1).

[0061] The calculation task 53 outputs combination data of frequencies from a first frequency flw to a second frequency fup, which are changed from the first frequency flw by a frequency change amount Δf, and the average value of the echo signal intensity in the oscillation line range.

[0062] The judgment task 54 receives the combined data of the frequency and the average value of the echo signal intensity output from the calculation task 53, and uses the combined data to judge the health (i.e., whether it is normal or abnormal) of the ultrasonic transducer of the transmitting / receiving unit 2 (step S6).

[0063] The judgment task 54 judges the soundness of the ultrasonic transducer of the transmitting / receiving unit 2 based on whether or not there is a valid / appropriate peak of the average value of the echo signal intensity in the range from the first frequency flw to the second frequency fup. The judgment method in the judgment task 54 is not limited to a specific method, and any method or procedure may be used as long as it can accurately judge whether or not there is a valid / appropriate peak of the average value of the echo signal intensity in the range from the first frequency flw to the second frequency fup.

[0064] Specifically, the judgment task 54 may judge the soundness of the ultrasonic transducer of the wave transmitting and receiving unit 2 according to one of the following two judgment methods.

[0065] (Judgment method 1) Of the combined data of the above frequencies and average echo signal intensities, the maximum value of the average echo signal intensities is Imax, the average echo signal intensities at the first frequency flw is Iflw, and the average echo signal intensities at the second frequency fup is Ifup. Also, the intensity threshold is Ti. If the following condition 1 is met, it is determined that the ultrasonic transducer of the transmitting / receiving unit 2 is normal, and if the following condition 1 is not met, it is determined that an abnormality has occurred in the ultrasonic transducer of the transmitting / receiving unit 2. (Condition 1) Imax-Iflw≧Ti and Imax-Ifup≧Ti (However, Ti>0)

[0066] The intensity threshold Ti is not limited to a specific value, but is appropriately set to an appropriate value in consideration of whether or not a peak of the average value of the echo signal intensity exists in the range from the first frequency flw to the second frequency fup. Specifically, the intensity threshold Ti may be set to any value in the range of about 5 to 7 dB, for example. (See also FIG. 3 and the above description relating to that figure).

[0067] A schematic diagram of a typical example of the relationship between the mode of variation of the average value of the echo signal intensity in the oscillation line range and the determination of the soundness of the ultrasonic transducer of the transmitting and receiving unit 2 is shown in FIG. 4. In FIG. 4(A), the difference between the maximum value Imax of the average value of the echo signal intensity and the average value Iflw of the echo signal intensity at the first frequency flw is greater than or equal to the intensity threshold value Ti (i.e., Imax - Iflw ≥ Ti), and the difference between the maximum value Imax of the average value of the echo signal intensity and the average value Ifup of the echo signal intensity at the second frequency fup is greater than or equal to the intensity threshold value Ti (i.e., Imax - Ifup ≥ Ti), and there is a proper / appropriate peak of the average value of the echo signal intensity in the range from the first frequency flw to the second frequency fup. That is, FIG. 4(A) is an example when the ultrasonic transducer of the transmitting and receiving unit 2 is normal.

[0068] In FIG. 4(B), the difference between the maximum value Imax of the average value of the echo signal intensity and the average value Iflw of the echo signal intensity at the first frequency flw is less than the intensity threshold value Ti (i.e., Imax - Iflw < Ti; provided that it is greater than 0), and the difference between the maximum value Imax of the average value of the echo signal intensity and the average value Ifup of the echo signal intensity at the second frequency fup is less than the intensity threshold value Ti (i.e., Imax - Ifup < Ti; provided that it is greater than 0), and there is no proper / appropriate peak of the average value of the echo signal intensity in the range from the first frequency flw to the second frequency fup. That is, FIG. 4(B) is an example when an abnormality has occurred in the ultrasonic vibration of the transmitting and receiving unit 2.

[0069] In FIG. 4(C), there is an average value of the echo signal intensity that is smaller than the average value Iflw of the echo signal intensity at the first frequency flw and the average value Ifup of the echo signal intensity at the second frequency fup, and there is no maximum value Imax of the average value of the echo signal intensity that forms a convex upward peak in the range from the first frequency flw to the second frequency fup, while there is a valley of the average value of the echo signal intensity that forms a convex downward peak, and there is no proper / appropriate peak of the average value of the echo signal intensity. That is, FIG. 4(C) is an example when an abnormality has occurred in the ultrasonic vibration of the transmitting and receiving unit 2.

[0070] (Judgment method 2) The soundness of the ultrasonic transducer of the wave transmitting / receiving unit 2 is judged according to the following steps 1 to 9 (see FIG. 5). The following steps 1 to 4 are performed in order from the first frequency flw to the second frequency fup. Then, the following steps 5 to 9 are performed.

[0071] In the following description, the average echo signal strength at frequency f is Iavg(f), Δf is the amount of frequency change when sweeping the transmission and reception frequencies (i.e., the frequency change pitch), Iavg(f+Δf) is the average of the echo signal strengths next to Iavg(f), and Iavg(f-Δf) is the average of the echo signal strengths immediately preceding Iavg(f).

[0072] Step 1 Calculate ΔIn(f)=Iavg(f+Δf)-Iavg(f).

[0073] Step 2 Calculate ΔIb(f)=Iavg(f)-Iavg(f-Δf).

[0074] Step 3 When ΔIb(f)≧0 and ΔIn(f)≦0 are satisfied, the point of Iavg(f) is determined to be the peak (point p in FIG. 5).

[0075] Step 4 When ΔIb(f)<0 and ΔIn(f)>0 are satisfied, the point of Iavg(f) is determined to be a valley (point t in FIG. 5).

[0076] Step 5 The maximum value among the peaks detected in step 3 above is taken as the local maximum value.

[0077] Step 6 The minimum value of Iavg(f) in the range from the first frequency flw to the resonant frequency f0 is set to the lower limit minimum value, and the minimum value of Iavg(f) in the range from the resonant frequency f0 to the second frequency fup is set to the upper limit minimum value.

[0078] Step 7 If no peak is detected by the above procedure 3, or if the peaks detected by the above procedure 3 continue for a number equal to or greater than the successive threshold value Tp, it is determined that an abnormality has occurred in the ultrasonic transducer of the wave transmitting / receiving unit 2.

[0079] The continuous threshold value Tp is not limited to a specific value, and is appropriately set to an appropriate value in consideration of whether or not a valid / appropriate peak of the average value of the echo signal intensity exists in the range from the first frequency flw to the second frequency fup. Specifically, the continuous threshold value Tp may be set to any value within the range of about 5 to 10, for example.

[0080] Step 8 If a valley is detected by the above step 4, the difference between Iavg(f) corresponding to the maximum value detected by the above step 5 and Iavg(f) corresponding to the valley detected by the above step 4 is calculated (if multiple valleys are detected, the difference is calculated for each of them), and if there is at least one valley whose difference is equal to or greater than the intensity threshold value Ti, it is determined that an abnormality has occurred in the ultrasonic transducer of the wave transmitting / receiving unit 2. Note that in this step 8, a threshold value different from the intensity threshold value Ti may be used, for example, a threshold value smaller than the intensity threshold value Ti may be used.

[0081] Step 9 When the difference between the maximum value detected in the above step 5 and the lower limit minimum value detected in the above step 6 is equal to or greater than the intensity threshold value Ti, and the difference between the maximum value and the upper limit minimum value detected in the above step 6 is equal to or greater than the intensity threshold value Ti, it is determined that the ultrasonic transducer of the wave transmitting / receiving unit 2 is normal. On the other hand, when the difference between the maximum value and the lower limit minimum value is less than the intensity threshold value Ti, or when the difference between the maximum value and the upper limit minimum value is less than the intensity threshold value Ti, it is determined that an abnormality has occurred in the ultrasonic transducer of the wave transmitting / receiving unit 2.

[0082] Then, the judgment task 54 outputs the judgment result of the soundness of the ultrasonic transducer of the wave transmitting / receiving unit 2 to the display unit 7, and the display unit 7 displays the judgment result.

[0083] When the judgment task 54 judges the soundness of the ultrasonic transducer of the transmitting / receiving unit 2 according to the judgment method 1, it may output, together with the judgment result, the maximum value Imax of the average value of the echo signal intensity, the average value Iflw of the echo signal intensity at the first frequency flw, and the average value Ifup of the echo signal intensity at the second frequency fup, as well as the value of "Imax-Iflw" and the value of "Imax-Ifup", and display them on the display unit 7.

[0084] When the judgment task 54 judges the soundness of the ultrasonic transducer of the wave transmitting / receiving unit 2 according to the judgment method 2, the judgment task 54 also judges the maximum value, the lower limit side minimum value, the upper limit side minimum value, In addition, the difference between the maximum value and the lower limit minimum value and the difference between the maximum value and the upper limit minimum value may be output and displayed on the display unit 7.

[0085] The decision task 54 may further output display data of a plot diagram of the combination data of the frequency and the average value of the echo signal intensity output from the calculation task 53, and cause the display unit 7 to display the plot diagram.

[0086] The inspection process of the vibrator by the vibrator inspection device 1 may be performed manually by directly operating the vibrator inspection device 1, or may be performed automatically after periodic execution conditions are set.Furthermore, the vibrator inspection device 1 may have a communication unit (not shown) having a function of transmitting / receiving / inputting / outputting signals / information transmitted via various wireless / wired communication networks, and may be configured to transmit / receive / input control commands, data, and the like via the communication unit, so that the inspection process of the vibrator is performed by remotely operating the vibrator inspection device 1.

[0087] In addition, the combined data of the frequency and the average value of the echo signal intensity output from the calculation task 53 may be output to the output unit 8, converted into a file in the output unit 8, and then transmitted via the communication unit, so that the combined data can be verified by an engineer outside the ship to remotely determine the soundness of the ultrasonic transducer.

[0088] According to the transducer inspection device 1 and the transducer inspection method of the embodiment, the depth sounder etc. itself executes various processes related to the transducer inspection to determine the soundness of the ultrasonic transducer, so there is no need for an engineer or technician to visit the target ship on which the depth sounder etc. is installed, and it is possible to reduce and shorten the effort, time, and cost required for checking the performance of the transducer, and in turn, it is possible to easily inspect the transducer of the depth sounder etc. In addition, since the depth sounder etc. itself determines the soundness of the ultrasonic transducer, it is possible to instantly check the soundness of the ultrasonic transducer, and in turn, it is possible to improve the usefulness of the transducer inspection method.

[0089] According to the transducer inspection device 1 of the embodiment, the frequency range for sweeping the transmission and reception frequencies is determined based on the resonant frequency f0 and the Q value of the ultrasonic transducer, so that it is possible to appropriately set the search / detection range for the peak of the average value of the echo signal intensity, thereby improving the reliability of the transducer inspection method.

[0090] According to the transducer inspection device 1 of the embodiment, the soundness of the ultrasonic transducer is determined based on whether or not the above condition 1 is satisfied between the maximum value Imax of the average echo signal intensity, the average value Iflw of the echo signal intensity at the first frequency flw, and the intensity threshold value Ti, and between the maximum value Imax of the average echo signal intensity, the average value Ifup of the echo signal intensity at the second frequency fup, and the intensity threshold value Ti. This makes it possible to appropriately determine the soundness of the ultrasonic transducer, and ultimately improves the reliability of the transducer inspection method.

[0091] Although the embodiment of the present invention has been described above, the specific configuration is not limited to the above embodiment, and even if there are design changes and the like within the scope of the gist of the present invention, they are included in the present invention.

[0092] For example, the above embodiment has been described assuming a depth sounder mounted on a ship, but the target to which the present invention can be applied is not limited to a depth sounder mounted on a ship, and the present invention can be applied to various transducers that can receive interference from their own transmission pulse. [Explanation of symbols]

[0093] 1. Transducer inspection equipment 2 Transmitter / receiver unit 3 Transmitter / receiver 31 Switching circuit 32 Transmitting circuit 33 Receiving circuit 34 Detector circuit 35 A / D converter 4 Processing section 41 Sampling Circuit 5. Inspection and calculation section 51 Frequency Control Task 52 Sampling Task 53 Computational Tasks 54 Judgment Task 6 Memory section 7 Display section 8 Output section

Claims

1. a means for transmitting ultrasonic waves into water while sweeping a transmission / reception frequency over a predetermined frequency range, and receiving the ultrasonic waves and converting them into an electric signal; a means for processing the electrical signal to calculate an average value of the echo signal strength, and for determining the soundness of a transducer that transmits and receives the ultrasonic waves into water based on whether or not a peak of the average value of the echo signal strength exists within the predetermined frequency range, the average value of the echo signal intensities is an average value of the echo signal intensities in a predetermined range including the oscillation line, The oscillation line corresponds to the leakage of the self-transmitted pulse.

4. An inspection device for a transducer comprising:

2. The first frequency f on the lower limit side of the predetermined frequency range and the second frequency f on the upper limit side are expressed by the following formulas 1A to 1C. (Equation 1A) fwd = f0 / Q (Math 1B) flw=f0-fwd / 2 (Math 1C) fup=f0+fwd / 2 where fwd is the width of the frequency range over which the transmission and reception frequencies are swept. f0: Resonant frequency of the oscillator Q: Q value of the transducer Determined by, 2. The oscillator inspection apparatus according to claim 1,

3. The maximum value of the average value of the echo signal strength is Imax, the average value of the echo signal strength at the first frequency f is Ifw, and the average value of the echo signal strength at the second frequency f is Ifup. In addition, the intensity threshold value is Ti. (Condition 1) Imax-Iflw≧Ti and Imax-Ifup≧Ti If the above condition 1 is satisfied, it is determined that the transducer is normal, and if the above condition 1 is not satisfied, it is determined that an abnormality has occurred in the transducer. The intensity threshold Ti is set to any value in the range of 5 to 7 dB.

3. The oscillator inspection apparatus according to claim 2.

4. A process of transmitting ultrasonic waves into water while sweeping a transmission and reception frequency over a predetermined frequency range, and receiving the ultrasonic waves and converting them into an electrical signal; and processing the electrical signal to calculate an average value of the echo signal strength, and judging the soundness of a transducer that transmits and receives the ultrasonic waves into water based on whether or not a peak of the average value of the echo signal strength exists within the predetermined frequency range. the average value of the echo signal intensities is an average value of the echo signal intensities in a predetermined range including the oscillation line, The oscillation line corresponds to the leakage of the self-transmitted pulse.

2. A method for inspecting a transducer comprising the steps of:

5. The first frequency f on the lower limit side of the predetermined frequency range and the second frequency f on the upper limit side are expressed by the following formulas 1A to 1C. (Equation 1A) fwd = f0 / Q (Math 1B) flw=f0-fwd / 2 (Math 1C) fup=f0+fwd / 2 where fwd is the width of the frequency range over which the transmission and reception frequencies are swept. f0: Resonant frequency of the oscillator Q: Q value of the transducer Determined by, 5. The method for inspecting a transducer according to claim 4.

6. The maximum value of the average value of the echo signal strength is Imax, the average value of the echo signal strength at the first frequency f is Ifw, and the average value of the echo signal strength at the second frequency f is Ifup. In addition, the intensity threshold value is Ti. (Condition 1) Imax-Iflw≧Ti and Imax-Ifup≧Ti If the above condition 1 is satisfied, it is determined that the transducer is normal, and if the above condition 1 is not satisfied, it is determined that an abnormality has occurred in the transducer. The intensity threshold Ti is set to any value in the range of 5 to 7 dB.

6. The method for inspecting a vibrator according to claim 5.

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