Measuring device, measuring method and equipment for sound wave flying time

Abstract

The invention discloses a sound wave flying time measuring device, method and equipment, and belongs to the field of sound wave flying time measurement. The sound wave flying time measuring device comprises a control module, a pulse generating unit, a transducer assembly, a first span time measuring unit, a second span time measuring unit, a first comparator and a second comparator. The first span time measuring unit, the second span time measuring unit and the pulse generating unit are electrically connected with the control module; the pulse generating unit is electrically connected with the transducer assembly, the first span time measuring unit and the second span time measuring unit, the transducer assembly is electrically connected with the first comparator and the second comparator, the first comparator is electrically connected with the first span time measuring unit, and the second comparator is electrically connected with the second span time measuring unit; the pulse generation unit is used for generating and outputting a periodic initial pulse train, and the transducer assembly is used for generating and transmitting a sound wave train when receiving the initial pulse train.

Description

Technical Field

[0001] The present application belongs to the field of acoustic wave transit time measurement, and specifically relates to an acoustic wave transit time measurement device, measurement method and equipment. Background Art

[0002] With the development of science and technology, the application of measurement by sound waves (including infrasound, sound waves with audible frequencies to human ears, and ultrasound) is becoming more and more widespread. Take the measurement of ultrasonic flight time as an example. Specifically, the ultrasonic wave is transmitted in the measuring tube, and the transmission time is affected by the fluid type and flow rate of the fluid in the measuring tube. Therefore, the parameter values ​​of the flow rate, flow rate and other parameters of the fluid in the measuring tube can be determined by measuring the time of ultrasonic wave propagation and flight in the measuring tube, combined with the parameters such as the propagation speed of ultrasonic wave in the fluid. Among them, one or more groups of transducers are set at both ends of the measuring tube. When one end is used as an excitation transducer, the other end is used as a response transducer. After the excitation transducer is excited, an ultrasonic wave is generated. The ultrasonic wave propagates in the fluid in the measuring tube, and then the ultrasonic wave propagates to the response transducer. The time for the ultrasonic wave to propagate in the fluid in the measuring tube is regarded as the time interval from the excitation transducer generating the ultrasonic wave to the response transducer receiving the ultrasonic wave. The time for the ultrasonic wave to propagate in the fluid in the measuring tube is also called the flight time of the ultrasonic wave. By setting the position and direction of the transducer assembly, the acoustic wave flight time measurement technology can also be used for ultrasonic ranging. However, in the related art, the measuring device and method for measuring the ultrasonic wave transit time for ultrasonic transit time are relatively complicated, which is not conducive to the engineering realization and practical application of the measuring device. Summary of the invention

[0003] The purpose of the embodiments of the present application is to provide a device, method and equipment for measuring the acoustic wave transit time, at least to solve the problem that the acoustic wave transit time measurement device and method for ultrasonic transit time measurement are relatively complex, thereby being more conducive to the engineering realization and practical application of the measurement device.

[0004] In a first aspect, an embodiment of the present application provides a device for measuring acoustic wave transit time, the device comprising: a control module, a pulse generating unit, a transducer assembly, a first span time measuring unit, a second span time measuring unit, a first comparator, and a second comparator;

[0005] The first span time measurement unit, the second span time measurement unit, and the pulse generation unit are all electrically connected to the control module; the pulse generation unit is electrically connected to the transducer assembly, the first span time measurement unit, and the second span time measurement unit, respectively; the transducer assembly is electrically connected to the first comparator and the second comparator, respectively; the first comparator is electrically connected to the first span time measurement unit, and the second comparator is electrically connected to the second span time measurement unit;

[0006] The pulse generating unit is used to generate and output a periodic initial pulse group, the transducer assembly is used to generate and transmit a sound wave group when receiving the initial pulse group, and the transducer assembly is also used to generate a response voltage wave group when receiving the sound wave group, and the response voltage wave group can be transmitted to the first comparator and the second comparator;

[0007] The first comparator is used to perform non-zero comparison and output a non-zero comparison pulse signal to the first span time measurement unit, and the second comparator is used to perform zero-crossing comparison, or first perform non-zero comparison and then perform zero-crossing comparison, and output a zero-crossing comparison pulse signal to the second span time measurement unit; the first span time measurement unit is used to measure the reference span time of the non-zero comparison pulse to obtain its measurement value and send it to the control module, and the second span time measurement unit is used to measure the reference span time of the zero-crossing comparison pulse to obtain its measurement value and send it to the control module;

[0008] The control module is used to determine the reference span time of the non-zero comparison pulse according to the measured value of the reference span time of the non-zero comparison pulse, and determine the reference span time of the zero-crossing comparison pulse according to the measured value of the reference span time of the zero-crossing comparison pulse, and determine whether the response voltage wave is attenuated according to the reference span time of the non-zero comparison pulse, and when the attenuation of the response voltage wave is greater than or equal to a preset attenuation threshold, stop measuring the sound wave flight time of the sound wave group, and determine the sound wave flight time of the sound wave group based on the reference span time of the zero-crossing comparison pulse.

[0009] Optionally, the device for measuring the acoustic wave transit time further comprises a pulse counting unit;

[0010] The pulse counting unit is electrically connected to the control module and the first comparator respectively, and is used to count the number of non-zero comparison pulse signals transmitted to the pulse counting unit, and transmit the counted number of non-zero comparison pulse signals to the control module.

[0011] Optionally, the device for measuring the acoustic wave flight time further comprises an analog gate;

[0012] The analog gate is electrically connected to the pulse generating unit and the transducer assembly, and is electrically connected to the first comparator and the second comparator. The analog gate is switched on so that the excitation voltage wave group corresponding to the initial pulse group emitted by the pulse generating unit is transmitted to the first comparator and the second comparator, or the response voltage wave group generated by the transducer assembly is transmitted to the first comparator and the second comparator.

[0013] Optionally, the device for measuring the acoustic wave transit time further comprises a first output buffer and a second output buffer, and the transducer assembly comprises a first transducer and a second transducer;

[0014] The first output buffer is electrically connected to the pulse generating unit and the first transducer respectively, and the second output buffer is electrically connected to the pulse generating unit and the second transducer respectively;

[0015] One of the first transducer and the second transducer serves as an excitation transducer, and the other serves as a response transducer. When the first output buffer is configured as an output state and the second output buffer is configured as a cut-off state, the first output buffer provides an excitation voltage and a current to the first transducer, so that the first transducer serves as an excitation transducer and the second transducer serves as a response transducer. The first transducer generates and transmits a sound wave group, the second transducer receives the sound wave group and generates a response voltage wave group, and the response transducer is electrically connected to the comparator. When the second output buffer is configured as an output state and the first output buffer is configured as a cut-off state, the second output buffer provides an excitation voltage and a current to the second transducer, so that the second transducer serves as an excitation transducer and the first transducer serves as a response transducer. The second transducer generates and transmits a sound wave group, the first transducer receives the sound wave group and generates a response voltage wave group, and the response transducer is electrically connected to the comparator.

[0016] Optionally, the device for measuring the acoustic wave transit time further comprises a measuring tube;

[0017] One of the first transducer and the second transducer is disposed at the first end of the measuring tube, and the other is disposed at the second end of the measuring tube.

[0018] Optionally, the device for measuring the acoustic wave transit time further comprises a third output buffer, and the transducer assembly comprises a third transducer;

[0019] The third output buffer is electrically connected to the pulse generating unit and the third transducer respectively.

[0020] Optionally, the device for measuring the acoustic wave transit time further comprises a reference voltage generating component, wherein the reference voltage generating component is electrically connected to the first comparator and the second comparator respectively, and the reference voltage generating component is used to transmit a reference voltage to the first comparator and the second comparator.

[0021] Optionally, the acoustic wave transit time measuring device further comprises a first coupling capacitor and a second coupling capacitor, and the transducer assembly comprises a first transducer and a second transducer;

[0022] The first coupling capacitor is electrically connected to the first transducer, and the second coupling capacitor is electrically connected to the second transducer;

[0023] Wherein, when the first transducer acts as a response transducer, the first coupling capacitor is used to couple the response voltage of the first transducer to the first comparator and the second comparator; when the second transducer acts as a response transducer, the second coupling capacitor is used to couple the response voltage of the second transducer to the first comparator and the second comparator.

[0024] Optionally, the device for measuring the acoustic wave transit time further comprises a third coupling capacitor, and the transducer assembly comprises a third transducer;

[0025] The third coupling capacitor is electrically connected to the third transducer;

[0026] Wherein, when the third transducer is used as a response transducer, the third coupling capacitor is used to couple the response voltage of the third transducer to the first comparator and the second comparator.

[0027] In a second aspect, an embodiment of the present application provides a method for measuring acoustic wave transit time, which is applied to the acoustic wave transit time measuring device described in any one of the first aspects above, and the measuring method includes:

[0028] Acquire a first measurement value of the first span time measurement unit and a second measurement value of the second span time measurement unit, wherein the first measurement value includes a measurement value of a reference span time of a non-zero comparison pulse, and the second measurement value includes a measurement value of a reference span time of a zero-crossing comparison pulse;

[0029] Determine a reference span time of a non-zero comparison pulse based on the first measurement value and use it as a first reference span time, and determine a reference span time of a zero-crossing comparison pulse based on the second measurement value and use it as a second reference span time;

[0030] determining whether the response voltage wave is attenuated based on the first reference span time;

[0031] When the attenuation amount of the response voltage wave is greater than or equal to a preset attenuation threshold, the measurement of the acoustic wave transit time of the acoustic wave group is stopped, and the acoustic wave transit time of the acoustic wave group is determined based on the second reference span time.

[0032] Optionally, determining whether the response voltage wave is attenuated based on the first reference span time includes:

[0033] Determine the reference span time of three consecutive non-zero comparison pulses, and the reference span time of the three non-zero comparison pulses are arranged in time sequence;

[0034] Determine a difference between a reference span time of the third non-zero comparison pulse and a reference span time of the second non-zero comparison pulse as a first difference, determine a difference between a reference span time of the second non-zero comparison pulse and a reference span time of the first non-zero comparison pulse as a second difference;

[0035] Determine a difference between the first difference and the second difference and use the difference as a first target difference;

[0036] If the first target difference is greater than or equal to the first preset difference threshold, it is determined that the response voltage wave is attenuated; if the first target difference is less than the first preset difference threshold, it is determined that the response voltage wave is not attenuated.

[0037] Optionally, before determining the reference span time of three consecutive non-zero comparison pulses, the method for measuring the acoustic wave flight time further includes:

[0038] Determine a reference span time of two consecutive non-zero comparison pulses, and the reference span times of the two non-zero comparison pulses are sequentially arranged in chronological order;

[0039] determining a difference between a reference span time of the second non-zero comparison pulse and a reference span time of the first non-zero comparison pulse, and using the difference as a third difference;

[0040] Determine a difference between the third difference and the pulse period of the initial pulse group and use it as a second target difference;

[0041] If the second target difference is less than a second preset difference threshold, the reference span times of three consecutive non-zero comparison pulses are determined starting from the reference span time of the first non-zero comparison pulse.

[0042] Optionally, determining whether the response voltage wave is attenuated based on the first reference span time includes:

[0043] Based on the first reference span time and the second reference span time, it is determined whether the response voltage wave is attenuated.

[0044] Optionally, determining whether the response voltage wave is attenuated based on the first reference span time and the second reference span time includes:

[0045] Determine a difference between a reference span time of the non-zero comparison pulse and a reference span time of the zero-crossing comparison pulse, and use the difference as a fourth difference;

[0046] Obtaining two consecutive fourth difference values, and determining a difference between the second fourth difference value and the first fourth difference value as a third target difference value;

[0047] If the third target difference is greater than or equal to the third preset difference threshold, it is determined that the response voltage wave is attenuated; if the third target difference is less than the third preset difference threshold, it is determined that the response voltage wave is not attenuated.

[0048] Optionally, determining whether the response voltage wave is attenuated based on the first reference span time and the second reference span time includes:

[0049] Determining a pulse span time of the non-zero comparison pulse based on a reference span time of the non-zero comparison pulse and a reference span time of the zero-crossing comparison pulse;

[0050] Determine the pulse span time of two consecutive non-zero comparison pulses, and determine the difference between the pulse span time of the second non-zero comparison pulse and the pulse span time of the first non-zero comparison pulse, and use it as the fourth target difference;

[0051] If the fourth target difference is less than the fourth preset difference threshold, it is determined that the response voltage wave is attenuated; if the fourth target difference is greater than or equal to the fourth preset difference threshold, it is determined that the response voltage wave is not attenuated.

[0052] Optionally, determining the pulse span time of the non-zero comparison pulse based on the reference span time of the non-zero comparison pulse and the reference span time of the zero-crossing comparison pulse comprises:

[0053] Determine a difference between a reference span time of the non-zero comparison pulse corresponding to the response voltage wave and a reference span time of the zero-crossing comparison pulse, and use the difference as a fourth difference;

[0054] Based on the fourth difference, a pulse span time of the non-zero comparison pulse is determined.

[0055] Optionally, determining the pulse span time of the non-zero comparison pulse based on the fourth difference includes:

[0056] The pulse span time of the non-zero comparison pulse is obtained by subtracting one half of the pulse period of the initial pulse group from twice the fourth difference value.

[0057] In a third aspect, an embodiment of the present application provides a device, which includes a device for measuring the acoustic wave transit time as described in any one of the first aspects above.

[0058] In the embodiment of the present application, the control module determines whether the response voltage wave is attenuated based on the reference span time of the non-zero comparison pulse, and when the attenuation of the response voltage wave is greater than or equal to the preset attenuation threshold, the measurement of the acoustic wave flying time of the acoustic wave group is stopped. The control module can use a time point of the target response wave before the time when the attenuation of the response voltage wave is greater than or equal to the preset attenuation threshold as the stop time of the acoustic wave flying. After that, the control module determines the stop time of the acoustic wave flying of the acoustic wave group based on the measured value of the reference span time of the zero-crossing comparison pulse. This stop time is an accurate time, and the start time of the acoustic wave flying is determined and accurate, so that based on the accurate start time and the accurate stop time, the acoustic wave flying time can be accurately determined, and then the corresponding other parameters can be accurately determined according to the accurate acoustic wave flying time. In addition, the structure of the acoustic wave flying time measuring device is relatively simple, and the principle and method of measuring the acoustic wave flying time are also relatively simple. That is, in the embodiment of the present application, not only can the acoustic wave transit time be accurately determined, but the structure of the acoustic wave transit time measuring device is relatively simple, and the method of measuring the acoustic wave transit time is also relatively simple, which is conducive to engineering realization and practical application. BRIEF DESCRIPTION OF THE DRAWINGS

[0059] Figure 1 A schematic diagram showing a device for measuring acoustic wave transit time provided in an embodiment of the present application;

[0060] Figure 2 One schematic diagram showing a device for measuring the acoustic wave transit time provided in an embodiment of the present application for measuring the flow rate of a fluid

[0061] Figure 3 One of the schematic diagrams showing a distance measurement by a device for measuring acoustic wave flight time provided in an embodiment of the present application;

[0062] Figure 4 A second schematic diagram showing a distance measurement using a device for measuring acoustic wave transit time provided in an embodiment of the present application;

[0063] Figure 5 A schematic diagram showing a device for measuring acoustic wave transit time provided in an embodiment of the present application for measuring transit time;

[0064] Figure 6A schematic diagram showing a device for measuring the acoustic wave transit time provided in an embodiment of the present application for measuring the attenuation of a response voltage wave;

[0065] Figure 7 A flow chart showing a method for measuring acoustic wave transit time provided in an embodiment of the present application.

[0066] Reference numerals:

[0067] 10: control module; 20: pulse generating unit; 30: transducer assembly; 31: first transducer; 32: second transducer; 33: third transducer; 41: first span time measuring unit; 42: second span time measuring unit; 51: first comparator; 52: second comparator; 60: pulse counting unit; 70: analog selector; 81: first output buffer; 82: second output buffer; 83: third output buffer; 90: measuring tube; 100: reference voltage generating assembly; 110: first reference voltage generating unit; 120: second reference voltage generating unit; 111: first coupling capacitor; 112: second coupling capacitor; 113: third coupling capacitor. DETAILED DESCRIPTION

[0068] The term "first" or "second" in the specification and claims of this application may include one or more of the features explicitly or implicitly. In the description of this application, unless otherwise specified, "plurality" means two or more. In addition, "and / or" in the specification and claims means at least one of the connected objects, and the character " / " generally means that the objects connected before and after are in an "or" relationship.

[0069] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0070] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0071] like Figures 1 to 6 As shown, the device for measuring the acoustic wave transit time includes: a control module 10 , a pulse generating unit 20 , a transducer assembly 30 , a first span time measuring unit 41 , a second span time measuring unit 42 , a first comparator 51 and a second comparator 52 .

[0072] The first span time measurement unit 41, the second span time measurement unit 42, and the pulse generation unit 20 are all electrically connected to the control module 10; the pulse generation unit 20 is electrically connected to the transducer assembly 30, the first span time measurement unit 41, and the second span time measurement unit 42, respectively; the transducer assembly 30 is electrically connected to the first comparator 51 and the second comparator 52, respectively; the first comparator 51 is electrically connected to the first span time measurement unit 41, and the second comparator 52 is electrically connected to the second span time measurement unit 42; the pulse generation unit 20 is used to generate and The transducer assembly 30 is used to output a periodic initial pulse group, and is used to generate and transmit a sound wave group when receiving the initial pulse group. The transducer assembly 30 is also used to generate a response voltage wave group when receiving the sound wave group, and the response voltage wave group can be transmitted to the first comparator 51 and the second comparator 52; the first comparator 51 is used to perform a non-zero comparison and output a non-zero comparison pulse signal, and the second comparator 52 is used to perform a zero-crossing comparison, or a first non-zero comparison, and then a zero-crossing comparison, and output a zero-crossing comparison pulse signal; the first comparator 51 transmits the non-zero comparison pulse signal to the second comparator 52. The first span time measurement unit 41 is passed to the second comparator 52, and the zero-crossing comparison pulse signal is passed to the second span time measurement unit 42. The first span time measurement unit 41 is used to measure the reference span time of the non-zero comparison pulse to obtain its measurement value, and send the measurement value of the reference span time of the non-zero comparison pulse to the control module 10. The second span time measurement unit 42 is used to measure the reference span time of the zero-crossing comparison pulse to obtain its measurement value, and send the measurement value of the reference span time of the zero-crossing comparison pulse to the control module 10. The control module 10 The reference span time of the non-zero comparison pulse can be determined according to the measured value of the reference span time of the non-zero comparison pulse, and the reference span time of the zero-crossing comparison pulse can be determined according to the measured value of the reference span time of the zero-crossing comparison pulse. The control module 10 determines whether the response voltage wave is attenuated according to the reference span time of the non-zero comparison pulse, and stops measuring the sound wave transit time of the sound wave group when the attenuation of the response voltage wave is greater than or equal to a preset attenuation threshold, and determines the sound wave transit time of the sound wave group based on the measured value of the reference span time of the zero-crossing comparison pulse.

[0073] In the embodiment of the present application, since the first span time measurement unit 41, the second span time measurement unit 42, and the pulse generating unit 20 are all electrically connected to the control module 10, the first span time measurement unit 41, the second span time measurement unit 42, and the pulse generating unit 20 can be controlled by the control module 10, or send signals to the control module 10, or the control module 10 can obtain required data from the first span time measurement unit 41, the second span time measurement unit 42, and the pulse generating unit 20. Since the pulse generating unit 20 is electrically connected to the transducer assembly 30, the first span time measurement unit 41, and the second span time measurement unit 42, once the pulse generating unit 20 generates an initial pulse group, the initial pulse group can be transmitted to the first span time measurement unit 41, the second span time measurement unit 42, and the transducer assembly 30, and the first span time measurement unit 41 and the second span time measurement unit 42 can receive the initial pulse group, and use the time of receiving the initial pulse group as the start time of the acoustic wave flying. After receiving the initial pulse group, the transducer assembly 30 can be excited so that the transducer assembly 30 generates an acoustic wave group, and the transducer assembly 30 generates a response voltage wave group when receiving the acoustic wave group. Since the transducer assembly 30 is electrically connected to the first comparator 51 and the second comparator 52, respectively, once the transducer assembly 30 generates a response voltage wave group, the response voltage wave group can be transmitted to the first comparator 51 and the second comparator 52, the first comparator 51 can perform a non-zero comparison and output a non-zero comparison pulse signal, and the second comparator 52 can perform a zero-crossing comparison and / or a non-zero comparison, and output a zero-crossing comparison pulse signal and / or a non-zero comparison pulse signal.Since the first comparator 51 is electrically connected to the first span time measurement unit 41, and the second comparator 52 is electrically connected to the second span time measurement unit 42, the first comparator 51 can transmit the non-zero comparison pulse signal to the first span time measurement unit 41, and the second comparator 52 transmits the zero-crossing comparison pulse signal and / or the non-zero comparison pulse signal to the second span time measurement unit 42, and the first span time measurement unit 41 can measure the reference span time of the non-zero comparison pulse to obtain its measurement value, and send the measurement value of the reference span time of the non-zero comparison pulse to the control module 10, and the second span time measurement unit 42 can measure the reference span time of the zero-crossing comparison pulse to obtain its measurement value. The measured value is obtained, and the measured value of the reference span time of the zero-crossing comparison pulse is sent to the control module 10. The control module 10 can determine the reference span time of the non-zero comparison pulse according to the measured value of the reference span time of the non-zero comparison pulse, and can determine the reference span time of the zero-crossing comparison pulse according to the measured value of the reference span time of the zero-crossing comparison pulse. The control module 10 determines whether the response voltage wave is attenuated according to the reference span time of the non-zero comparison pulse, and when the attenuation of the response voltage wave is greater than or equal to the preset attenuation threshold, the measurement of the acoustic wave flight time of the acoustic wave group is stopped, and the acoustic wave flight time of the acoustic wave group is determined based on the measured value of the reference span time of the zero-crossing comparison pulse. Among them, the control module 10 can use a time point of the target response wave before the time when the attenuation of the response voltage wave is greater than or equal to the preset attenuation threshold as the stop time of the acoustic wave flight. After determining the start time and end time of the acoustic wave flight time measurement, the acoustic wave flight time of the corresponding acoustic wave group can be determined.

[0074] That is, in the embodiment of the present application, the control module 10 determines whether the response voltage wave is attenuated based on the reference span time of the non-zero comparison pulse, and when the attenuation of the response voltage wave is greater than or equal to the preset attenuation threshold, the measurement of the acoustic wave flight time of the acoustic wave group is stopped. The control module 10 can use a time point of the target response wave before the time when the attenuation of the response voltage wave is greater than or equal to the preset attenuation threshold as the stop time of the acoustic wave flight, and then the control module 10 determines the stop time of the acoustic wave flight of the acoustic wave group based on the measured value of the reference span time of the zero-crossing comparison pulse. This stop time is an accurate time, and the start time of the acoustic wave flight is determined and accurate, so that based on the accurate start time and the accurate stop time, the acoustic wave flight time can be accurately determined, and then the corresponding other parameters can be accurately determined according to the accurate acoustic wave flight time. In addition, the structure of the acoustic wave flight time measuring device is relatively simple, and the principle and method of measuring the acoustic wave flight time are also relatively simple. That is, in the embodiment of the present application, not only can the acoustic wave transit time be accurately determined, but the structure of the acoustic wave transit time measuring device is relatively simple, and the method of measuring the acoustic wave transit time is also relatively simple, which is conducive to engineering realization and practical application.

[0075] It should be noted that after the pulse generating unit 20 generates the initial pulse group, the initial pulse group is transmitted to the transducer assembly 30, which can excite the transducer assembly 30 to generate a sound wave group. The transducer assembly 30 that is not driven by the pulse generating unit 20 generates a response voltage wave group after receiving the sound wave group. The response voltage wave in the response voltage wave group is usually a quasi-sine wave. In this process, the initial pulse group is transmitted to the transducer assembly 30, the transducer assembly 30 generates and emits a sound wave group, and the sound wave group is transmitted to the transducer assembly 30, so that the transducer assembly 30 not driven by the pulse generating unit 20 generates a response voltage wave group, which is equivalent to the initial pulse group continuously exciting the transducer assembly 30, the transducer assembly 30 continuously generating and emitting a sound wave group, and the transducer assembly 30 that is not excited by the initial pulse group is continuously excited to generate a response voltage wave group when receiving the continuous sound wave group, and the peak amplitude of the response voltage wave in the generated response voltage wave group must gradually increase until the transducer assembly 30 reaches a resonant state with the same initial pulse frequency, at which time the peak amplitude of the response voltage wave in the response voltage wave group remains unchanged, and the peak amplitude reaches a maximum value. Once the pulse generating unit 20 stops generating the initial pulse group, which is equivalent to stopping the energy output to the transducer assembly 30, the transducer assembly 30 used as the excitation transducer immediately stops generating and emitting sound waves, so that the transducer assembly 30 used as the response transducer no longer receives the sound waves and loses the excitation kinetic energy, causing the transducer to stop resonating and immediately begin to decay, so that the response voltage wave in the response voltage wave group will inevitably begin to decay, that is, the peak amplitude of the response voltage wave will inevitably begin to decay. When the non-zero comparison reference voltage remains unchanged, the pulse span time of the non-zero comparison pulse of the response voltage wave will inevitably decay. The control module 10 can determine whether the response voltage wave is attenuated based on the reference span time of the non-zero comparison pulse, and when the attenuation of the response voltage wave is greater than or equal to the preset attenuation threshold, stop measuring the sound wave flight time of the sound wave group and determine the stop time. The start time of the sound wave flight is controlled by the control module 10, which is certain and accurate, and thus the sound wave flight time can be determined.

[0076] It should also be noted that, in the embodiment of the present application, the transducer assembly 30 is an energy conversion device that can work bidirectionally, and can be excited by the initial pulse group to emit sound waves, and can also be excited by receiving sound waves to generate response voltage waves. That is, after the transducer assembly 30 driven by the pulse generating unit 20 receives the initial pulse group, the transducer assembly 30 can be excited so that the transducer assembly 30 generates a sound wave group, and the transducer assembly 30 not driven by the pulse generating unit 20 will generate a response voltage wave group when receiving the sound wave group.

[0077] In addition, in the embodiment of the present application, the second comparator 52 may only perform a zero-crossing comparison and output a zero-crossing comparison pulse signal. Of course, the second comparator 52 may also first perform a non-zero comparison and then perform a zero-crossing comparison, so that the second comparator 52 first outputs a non-zero comparison pulse signal and then outputs a zero-crossing comparison pulse signal. Among them, when the second comparator 52 only performs a zero-crossing comparison, at this time, when the first comparator 51 outputs the first non-zero comparison pulse signal, the first comparator 51 may send a signal to the second comparator 52, so that the second comparator 52 outputs a valid zero-crossing comparison pulse signal. Before the first comparator 51 outputs a non-zero comparison signal, the second comparator 52 may perform a zero-crossing comparison, but the second comparator 52 does not output a zero-crossing comparison pulse signal or the output zero-crossing comparison pulse signal is marked as invalid. For example, Figure 4 As shown, Figure 4 The non-zero comparison pulse signal in is output by the first comparator 51, Figure 4 The pulse signal of the zero-crossing comparison is output by the second comparator 52, that is, the second comparator 52 only outputs when performing zero-crossing comparison. Figure 4 The pulse signal of the reference switching in is output by the second comparator 52, that is, the second comparator 52 first performs a non-zero comparison and then performs a zero-crossing comparison, and the output signal is as follows: Figure 4 As shown in the reference switching comparison pulse signal, a non-zero comparison pulse signal is output first, and then a zero-crossing comparison pulse signal is output.

[0078] In addition, in the embodiment of the present application, the control module 10 is also used to: determine the reference span time of three consecutive non-zero comparison pulses, and the reference span time of the three non-zero comparison pulses are arranged in chronological order; determine the difference between the reference span time of the third non-zero comparison pulse and the reference span time of the second non-zero comparison pulse, and use it as the first difference; determine the difference between the reference span time of the second non-zero comparison pulse and the reference span time of the first non-zero comparison pulse, and use it as the second difference; determine the difference between the first difference and the second difference, and use it as the first target difference; if the first target difference is greater than or equal to the first preset difference threshold, it is determined that the response voltage wave is attenuated; if the first target difference is less than the first preset difference threshold, it is determined that the response voltage wave is not attenuated.

[0079] In addition, in an embodiment of the present application, the control module 10 is also used to: determine the reference span time of two consecutive non-zero comparison pulses, and the reference span times of the two non-zero comparison pulses are arranged in chronological order; determine the difference between the reference span time of the second non-zero comparison pulse and the reference span time of the first non-zero comparison pulse, and use it as the third difference; determine the difference between the third difference and the pulse period of the initial pulse group, and use it as the second target difference; if the second target difference is less than the second preset difference threshold, then determine the reference span time of three consecutive non-zero comparison pulses starting from the reference span time of the first non-zero comparison pulse.

[0080] In addition, in the embodiment of the present application, the control module 10 is also used to determine whether the response voltage wave is attenuated based on the first reference span time and the second reference span time. The first reference span time is the reference span time of the non-zero comparison pulse determined based on the first measurement value, and the second reference span time is the reference span time of the zero-crossing comparison pulse determined based on the second measurement value.

[0081] The reference span time is the span time of the target response pulse signal target edge relative to the target initial pulse signal target edge, such as Figure 5 In the example, the reference span time can be selected as the span time of the leading edge of the target response pulse signal relative to the leading edge of the target initial pulse signal. Of course, the reference span time can be selected as the span time of any edge of the target response pulse signal relative to any edge of the target initial pulse signal. This embodiment of the present application does not limit this.

[0082] In addition, in the embodiment of the present application, the control module 10 is also used to: determine the difference between the reference span time of the non-zero comparison pulse and the reference span time of the zero-crossing comparison pulse, and use it as the fourth difference; obtain two consecutive fourth differences, and determine the difference between the second fourth difference and the first fourth difference, as the third target difference; if the third target difference is greater than or equal to the third preset difference threshold, it is determined that the response voltage wave is attenuated; if the third target difference is less than the third preset difference threshold, it is determined that the response voltage wave is not attenuated.

[0083] In addition, in the embodiment of the present application, the control module 10 is also used to: determine the pulse span time of the non-zero comparison pulse based on the reference span time of the non-zero comparison pulse and the reference span time of the zero-crossing comparison pulse; determine the pulse span time of two consecutive non-zero comparison pulses, and determine the difference between the pulse span time of the second non-zero comparison pulse and the pulse span time of the first non-zero comparison pulse, and use it as the fourth target difference; if the fourth target difference is less than the fourth preset difference threshold, it is determined that the response voltage wave is attenuated; if the fourth target difference is greater than or equal to the fourth preset difference threshold, it is determined that the response voltage wave is not attenuated.

[0084] In the embodiment of the present application, the pulse span time of the non-zero comparison pulse refers to: the time spanned from the leading edge to the trailing edge of the non-zero comparison pulse.

[0085] In addition, in an embodiment of the present application, the control module 10 is also used to: determine the difference between the reference span time of the non-zero comparison pulse corresponding to the response voltage wave and the reference span time of the zero-crossing comparison pulse, and use it as the fourth difference; based on the fourth difference, determine the pulse span time of the non-zero comparison pulse.

[0086] In addition, in the embodiment of the present application, the control module 10 is further configured to: subtract one half of the pulse period of the initial pulse group from twice the fourth difference value to obtain a pulse span time of the non-zero comparison pulse.

[0087] In addition, in some embodiments, Figure 1 As shown, the measuring device for the acoustic wave flight time also includes an analog gate 70; the analog gate 70 is electrically connected to the pulse generating unit 20 and the transducer assembly 30, and the analog gate 70 is electrically connected to the first comparator 51 and the second comparator 52. The analog gate 70 is switched on to transmit the excitation voltage wave group corresponding to the initial pulse group emitted by the pulse generating unit 20 to the first comparator 51 and the second comparator 52, or to transmit the response voltage wave group generated by the transducer assembly 30 to the first comparator 51 and the second comparator 52.

[0088] Among them, the analog gate 70 can be configured to switch the input signal source that is turned on, so that when the excitation voltage wave group corresponding to the initial pulse group emitted by the pulse generating unit 20 is transmitted to the analog gate 70, the analog gate 70 can be configured so that the excitation voltage wave group is turned on, and then the excitation voltage wave group is transmitted to the first comparator 51 and the second comparator 52, so that the initial pulse group can trigger the first span time measurement unit 41 and the second span time measurement unit 42 to start the span time measurement count. Once the initial pulse group is partially or completely transmitted, the analog gate 70 can be configured to disconnect the path for transmitting the initial pulse group, so that the excitation voltage wave group cannot pass through the analog gate 70, and cannot be continuously transmitted to the first comparator 51 and the second comparator 52. And the analog gate 70 can be configured to conduct the path of the response voltage wave group generated by the transducer assembly 30, so that the response voltage wave group can be continuously transmitted to the first comparator 51 and the second comparator 52, and then the response voltage wave group can trigger the first span time measurement unit 41 and the second span time measurement unit 42 to perform measurement count sampling to obtain the count value of the corresponding span time.

[0089] It should be noted that the analog gate 70 is electrically connected to the response transducer and may also be electrically connected to the excitation transducer.

[0090] It should also be noted that, based on the functions of the analog gate 70 in the embodiment of the present application, a circuit that uses basic circuits such as analog switches to implement the same functions of the analog gate 70 can also be derived, and those skilled in the art can flexibly set it according to the needs of the actual device and the feasibility of various basic circuits. This application does not limit this.

[0091] In addition, in some embodiments, Figure 1 As shown, the measuring device for the acoustic wave flight time further includes a first output buffer 81 and a second output buffer 82, and the transducer assembly 30 includes a first transducer 31 and a second transducer 32; the first output buffer 81 is electrically connected to the pulse generating unit 20 and the first transducer 31 respectively, and the second output buffer 82 is electrically connected to the pulse generating unit 20 and the second transducer 32 respectively; one of the first transducer 31 and the second transducer 32 serves as an excitation transducer, and the other serves as a response transducer. When the first output buffer 81 is configured as an output state and the second output buffer 82 is configured as a cut-off state, the first output buffer 81 provides an excitation voltage and a current for the first transducer 31. So that the first transducer 31 acts as an excitation transducer, the second transducer 32 acts as a response transducer, the first transducer 31 generates and transmits a sound wave group, the second transducer 32 receives the sound wave group and generates a response voltage wave group, and the response transducer is electrically connected to the comparator; when the second output buffer 82 is configured to the output state and the first output buffer 81 is configured to the cut-off state, the second output buffer 82 provides an excitation voltage and current to the second transducer 32, so that the second transducer 32 acts as an excitation transducer, the first transducer 31 acts as a response transducer, the second transducer 32 generates and transmits a sound wave group, the first transducer 31 receives the sound wave group and generates a response voltage wave group, and the response transducer is electrically connected to the comparator.

[0092] Since the first output buffer 81 is electrically connected to the pulse generating unit 20 and the first transducer 31 respectively, and the second output buffer 82 is electrically connected to the pulse generating unit 20 and the second transducer 32 respectively, the functions of the first transducer 31 and the second transducer 32 can be switched by configuring the states of the first output buffer 81 and the second output buffer 82. Specifically, when the first output buffer 81 is configured to be in the output state and the second output buffer 82 is configured to be in the cut-off state, the first output buffer 81 can provide the excitation voltage and current to the first transducer 31, and the second output buffer 82 does not provide the excitation voltage and current to the second transducer 32, so that the first transducer 31 is excited to act as an excitation transducer, and the second transducer 32 acts as a response transducer, and the first transducer 31 generates and transmits a sound wave group. After the sound wave group is transmitted, the second transducer 32 can receive the sound wave group and generate a response voltage wave group, and the response transducer is electrically connected to the first comparator 51 and the second comparator 52, so that the response voltage group can be transmitted to the first comparator 51 and the second comparator 52. 2; When the second output buffer 82 is configured to be in the output state and the first output buffer 81 is configured to be in the cut-off state, the second output buffer 82 can provide the second transducer 32 with an excitation voltage and current, and the first output buffer 81 does not provide the first transducer 31 with an excitation voltage and current, so that the second transducer 32 is excited to act as an excitation transducer, and the first transducer 31 acts as a response transducer, and the second transducer 32 generates and transmits a sound wave group. After the sound wave group is transmitted, the first transducer 31 can receive the sound wave group and generate a response voltage wave group, and the response transducer is electrically connected to the first comparator 51 and the second comparator 52, so that the response voltage wave group can be transmitted to the first comparator 51 and the second comparator 52.

[0093] It should be noted that, in the embodiment of the present application, the distance can be measured by using the measuring device of the acoustic wave flight time. At this time, the first output buffer 81 can provide the excitation voltage and current to the first transducer 31, and the second output buffer 82 is in the cut-off state. The first transducer 31 acts as an excitation transducer, and the second transducer 32 acts as a response transducer. After the excitation transducer emits the sound wave, the sound wave is transmitted to the obstacle, and the sound wave is blocked by the obstacle and reflected, so that the sound wave is transmitted to the response transducer. When the response transducer receives the sound wave, it can generate a response voltage wave. In the embodiment of the present application, the flight time of the sound wave can be accurately determined, and the speed of the sound wave transmission in the current medium can be used to accurately determine the distance between the excitation transducer and the obstacle. For example, the measuring device of the acoustic wave flight time in the embodiment of the present application is installed on a vehicle, a ship, or a submarine, so that the distance between the measuring device of the acoustic wave flight time and the obstacle can be more accurately determined.

[0094] In addition, in some embodiments, the device for measuring the acoustic wave transit time further includes a measuring tube 90 ; one of the first transducer 31 and the second transducer 32 is disposed at a first end of the measuring tube 90 , and the other is disposed at a second end of the measuring tube 90 .

[0095] Through such a setting, after the excitation transducer emits a sound wave, the sound wave flies and transmits in the fluid in the measuring tube 90, and then the response transducer can receive the sound wave, so that the response transducer generates a response voltage wave group. Through the sound wave flight time measurement device in the embodiment of the present application, the sound wave flight time can be accurately determined, and then the flow rate of the fluid in the measuring tube 90 can be accurately determined, so as to more accurately determine parameters such as flow rate.

[0096] It should be noted that when the device for measuring the acoustic wave flight time includes a measuring tube 90, the flow rate of the fluid in the measuring tube 90 can also be accurately determined, and parameters such as the flow rate can be determined more accurately. Therefore, the measuring device provided in the embodiment of the present application can be applied to a water meter, so that parameters such as the flow rate and flow rate of water flowing through the measuring tube 90 can be determined more accurately.

[0097] In addition, in some embodiments, Figure 4 As shown, the device for measuring the acoustic wave transit time further includes a third output buffer 83, and the transducer assembly 30 includes a third transducer 33; the third output buffer 83 is electrically connected to the pulse generating unit 20 and the third transducer 33 respectively.

[0098] The third output buffer 83 is electrically connected to the pulse generating unit 20 and the third transducer 33 respectively, and the third transducer 33 is electrically connected to the first comparator 51 and the second comparator 52; when the third output buffer 83 is configured to be in the output state, the third output buffer 83 provides the third transducer 33 with an excitation voltage and a current, and the third transducer 33 generates and transmits a sound wave group; when the third output buffer 83 is configured to be in the cut-off state, the third output buffer 83 stops providing the third transducer 33 with an excitation voltage and a current, and at this time the third transducer 33 is used as a response transducer, and the third transducer 33 generates a response voltage wave group when receiving the sound wave group.

[0099] In addition, by setting the third output buffer 83, the third transducer 33 can be switched between different working conditions by adjusting the state of the third output buffer 83, thereby realizing different functions. Specifically, when the third output buffer 83 is configured to be in the output state, the third output buffer 83 can provide the third transducer 33 with an excitation voltage and current, at which time the third transducer 33 is used as an excitation transducer, and the third transducer 33 generates and transmits a sound wave group; when the third output buffer 83 is configured to be in the cut-off state, the third output buffer 83 stops providing the third transducer 33 with an excitation voltage and current, at which time the third transducer 33 is used as a response transducer, and the third transducer 33 generates a response voltage wave group when receiving the sound wave group. That is, by setting the state of the third output buffer 83, the third transducer 33 can transmit a sound wave group, and the third transducer 33 can also receive a sound wave group, so that the transmission and reception of the sound wave group can be realized through a single transducer, which is conducive to reducing costs.

[0100] Among them, the distance measurement can be performed through the sound wave flight time measuring device of the embodiment of the present application. In a specific application, the third output buffer 83 can be first configured to be in a driving state, that is, the third output buffer 83 provides an excitation voltage and current to the third transducer 33, and the third transducer 33 emits a sound wave group. Then, the third output buffer 83 can be configured to be in a cutoff state. After the sound wave group collides with an obstacle, it will be blocked, so that the sound wave group is reflected to the third transducer 33, and the third transducer 33 can receive the sound wave group and generate a response voltage wave group. In the present application, the sound wave flight time can be determined more accurately, so that the distance between the sound wave flight time measuring device and the obstacle can be determined more accurately.

[0101] In addition, in some embodiments, Figure 1 As shown, the device for measuring the acoustic wave flight time also includes a reference voltage generating component 100, which is electrically connected to the first comparator 51 and the second comparator 52 respectively, and is used to transmit a reference voltage to the first comparator 51 and the second comparator 52.

[0102] By setting the reference voltage generating component 100, the control module 10 can control the reference voltage generating component 100 to provide the first comparator 51 and the second comparator 52 with a comparison reference voltage, and the first comparator 51 and the second comparator 52 both have a comparison reference terminal, and the reference voltage generating component 100 can be electrically connected to the comparison reference terminal. Once the reference voltage generating component 100 generates the comparison reference voltage, the comparison reference voltage can be transmitted to the comparison reference terminal. When the signal voltage input to the input signal terminal of the first comparator 51 and the second comparator 52 changes from a voltage less than the comparison reference terminal to a voltage greater than the comparison reference terminal, and then changes from a voltage greater than the comparison reference terminal to a voltage less than the comparison reference terminal, the first comparator 51 and the second comparator 52 will output a comparison pulse. That is, by setting the reference voltage generating component 100, the first comparator 51 and the second comparator 52 can compare the voltage of their input signal terminal with the voltage of the comparison reference terminal to determine whether to output a comparison pulse.

[0103] It should be noted that the reference voltage generating component 100 may include a first reference voltage generating unit 110 and a second reference voltage generating unit 120. The first reference voltage generating unit 110 is electrically connected to the first comparator 51, and the second reference voltage generating unit 120 is electrically connected to the second comparator 52. The first reference voltage generating unit 110 transmits a reference voltage to the first comparator 51, and the second reference voltage generating unit 120 transmits another reference voltage to the second comparator 52. Of course, the reference voltage generating component 100 may only include the first reference voltage generating unit 110. In this case, the first reference voltage generating unit 110 is electrically connected to the first comparator 51 and the second comparator 52, respectively, so that the first reference voltage generating unit 110 transmits the required reference voltages to the first comparator 51 and the second comparator 52, respectively.

[0104] In addition, in some embodiments, Figure 1 As shown, the device for measuring the acoustic wave flight time also includes a pulse counting unit 60; the pulse counting unit 60 is electrically connected to the control module 10 and the first comparator 51 respectively, and the pulse counting unit 60 is used to count the number of non-zero comparison pulse signals transmitted to the pulse counting unit 60, and transmit the counted number of non-zero comparison pulse signals to the control module 10.

[0105] By setting the pulse counting unit 60, the pulse counting unit 60 can transmit the counted number of non-zero comparison pulses to the control module 10, so that the control module 10 can determine whether the reference comparison voltage provided by the reference voltage generating component 100 to the comparator is appropriate, whether the current excitation response wave group measurement overflows, and whether the span time measurement module should stop measuring based on the number of non-zero comparison pulses transmitted by the pulse counting unit 60 and the initial number of pulses emitted by the pulse generating unit 20.

[0106] In addition, in some embodiments, Figure 1 As shown, the device for measuring the acoustic wave flight time also includes a first coupling capacitor 111 and a second coupling capacitor 112, and the transducer assembly 30 includes a first transducer 31 and a second transducer 32; the first coupling capacitor 111 is electrically connected to the first transducer 31, and the second coupling capacitor 112 is electrically connected to the second transducer 32; wherein, when the first transducer 31 acts as a response transducer, the first coupling capacitor 111 is used to couple the response voltage of the first transducer 31 to the first comparator 51 and the second comparator 52; when the second transducer 32 acts as a response transducer, the second coupling capacitor 112 is used to couple the response voltage of the second transducer 32 to the first comparator 51 and the second comparator 52.

[0107] By setting the first coupling capacitor 111 and the second coupling capacitor 112, when the first transducer 31 is used as a response transducer, the first coupling capacitor 111 can be used, and when the second transducer 32 is used as a response transducer, the second coupling capacitor 112 can be used, according to actual needs, so that the internal circuit design of the acoustic wave flight time measuring device is relatively simple. In addition, by setting the first transducer 31 and the second transducer 32, the distance measurement can be performed by the acoustic wave flight time measuring device, and when the acoustic wave flight time measuring device includes a measuring tube 90, the flow velocity, flow rate and other parameters of the fluid in the measuring tube 90 can also be measured.

[0108] In addition, in some embodiments, the acoustic wave flight time measuring device may further include a third coupling capacitor 113, the transducer assembly 30 includes a third transducer 33; the third coupling capacitor 113 is electrically connected to the third transducer 33; wherein, when the third transducer 33 is used as a response transducer, the third coupling capacitor 113 is used to couple the response voltage of the third transducer 33 to the first comparator 51 and the second comparator 52. By providing the third transducer 33, the distance measurement can be performed by the acoustic wave flight time measuring device.

[0109] In addition, in the embodiment of the present application, the control module 10 may include but is not limited to a central processing unit, a host computer, and a local control unit inside the first span time measurement unit 41 and / or the second span time measurement unit 42. Any component with control and calculation functions can be used as the control module 10. For example, the control module 10 can be a chip with a control function. For another example, the control module 10 can be a circuit board with a control function. For another example, the control module 10 can be a local control unit inside the first span time measurement unit 41 and / or the second span time measurement unit 42, or it can be a combination of a central processing unit / host computer and a local control unit. In this regard, the embodiment of the present application is not limited here.

[0110] When a local control unit is provided inside the first span time measurement unit 41 , the local control unit of the first span time measurement unit 41 can determine the reference span time of the non-zero comparison pulse according to the first measurement value.

[0111] When a local control unit is provided inside the second span time measurement unit 42 , the local control unit of the second span time measurement unit 42 can determine the reference span time of the non-zero comparison pulse according to the second measurement value.

[0112] It should be noted that in the embodiments of the present application,

[0113] The present application embodiment provides a method for measuring the acoustic wave transit time, which is applied to the acoustic wave transit time measuring device in any of the above embodiments, such as Figure 7 As shown, the measurement method includes:

[0114] Step 701: Obtain a first measurement value of a first span time measurement unit and a second measurement value of a second span time measurement unit, wherein the first measurement value includes a measurement value of a reference span time of a non-zero comparison pulse, and the second measurement value includes a measurement value of a reference span time of a zero-crossing comparison pulse.

[0115] The control module is electrically connected to the first span time measurement unit and the second span time measurement unit respectively, so that the control module can obtain the first measurement value of the first span time measurement unit and the second measurement value of the second span time measurement unit.

[0116] Step 702: Determine a reference span time of a non-zero comparison pulse based on the first measurement value and use it as the first reference span time, and determine a reference span time of a zero-crossing comparison pulse based on the second measurement value and use it as the second reference span time.

[0117] Among them, once the control module obtains the first measurement value, the reference span time of the non-zero comparison pulse can be determined according to the first measurement value. Specifically, the control module can multiply the first measurement value with the counting time resolution of the first span time measurement unit to obtain the reference span time of the non-zero comparison pulse. In addition, once the control module obtains the second measurement value, the reference span time of the zero-crossing comparison pulse can be determined according to the second measurement value. Specifically, the control module can multiply the second measurement value with the counting time resolution of the second span time measurement unit to obtain the reference span time of the zero-crossing comparison pulse.

[0118] Step 703: Determine whether the response voltage wave is attenuated based on the first reference span time.

[0119] Once the control module determines the first reference span time, the control module may determine whether the response voltage wave decays based on the first reference span time.

[0120] In some implementations, step 602 may be implemented as follows: determining the reference span time of three consecutive non-zero comparison pulses, and the reference span time values ​​of the three non-zero comparison pulses are arranged in chronological order; determining the difference between the reference span time of the third non-zero comparison pulse and the reference span time of the second non-zero comparison pulse, and using it as the first difference; determining the difference between the reference span time of the second non-zero comparison pulse and the reference span time of the first non-zero comparison pulse, and using it as the second difference; determining the difference between the first difference and the second difference, and using it as the first target difference; if the first target difference is greater than or equal to the first preset difference threshold, determining that the response voltage wave is attenuated; if the first target difference is less than the first preset difference threshold, determining that the response voltage wave is not attenuated.

[0121] For example, the reference span times of three consecutive non-zero comparison pulses are 27050, 28050, and 29067, respectively. These three values ​​are arranged in chronological order. The first difference is determined to be 29067-28050=1017, and the second difference is determined to be 28050-27050=1000. The first target difference obtained by subtracting the first difference from the second difference is 1017-1000=17, and the first preset difference threshold is set to 15. If 17 is greater than 15, it is determined that the response voltage wave is attenuated. If the first preset difference threshold is set to 20 and 17 is less than 20, it is determined that the response voltage wave is not attenuated.

[0122] It should be noted that the first preset difference threshold is set according to actual needs, and the specific value of the first preset difference threshold is not limited in the embodiment of the present application.

[0123] In some implementations, before determining the reference span time of three consecutive non-zero comparison pulses, the method for measuring the acoustic wave flight time also includes: determining the reference span time of two consecutive non-zero comparison pulses, and the reference span times of the two non-zero comparison pulses are arranged in chronological order; determining the difference between the reference span time of the second non-zero comparison pulse and the reference span time of the first non-zero comparison pulse, and using it as the third difference; determining the difference between the third difference and the pulse period of the initial pulse group, and using it as the second target difference; if the second target difference is less than the second preset difference threshold, determining the reference span time of three consecutive non-zero comparison pulses starting from the measured value of the reference span time of the first non-zero comparison pulse.

[0124] For example, the measured values ​​of the reference span time of two consecutive non-zero comparison pulses are 27050 and 28050 respectively, and these two values ​​are arranged in chronological order, then the third difference is determined to be 28050-27050=1000, and the pulse period of the initial pulse group is 1000, then the difference between the third difference and the pulse period of the initial pulse group is 0, that is, the second target difference is 0, and the second preset difference threshold is set to 3, 0 is less than 3, which indicates that the response voltage wave corresponding to the two consecutive non-zero comparison pulses is in a resonant state, then the reference span time of the three consecutive non-zero comparison pulses is determined starting from the reference span time of the first non-zero comparison pulse, so that it can be more accurately determined whether the response voltage wave is attenuated. That is, the second target difference is less than the second preset difference threshold, indicating that the response voltage wave corresponding to two consecutive non-zero comparison pulses is in a resonant state. Therefore, after the initial pulse group stops transmitting, the excitation transducer stops generating and transmitting the sound wave due to the loss of excitation energy, and the receiving transducer loses the excitation momentum of the sound wave group, and its resonant state will inevitably decay due to the lack of continuous momentum excitation. Therefore, it is possible to more accurately determine whether the response voltage wave is attenuated.

[0125] It should be noted that the second preset difference threshold is set according to actual needs, and the specific value of the second preset difference threshold is not limited in the embodiment of the present application.

[0126] In some implementations, determining whether the response voltage wave is attenuated based on the first reference span time may be implemented by determining whether the response voltage wave is attenuated based on the first reference span time and the second reference span time.

[0127] In some implementations, based on the first reference span time and the second reference span time, the implementation method for determining whether the response voltage wave has attenuated can be: determining the difference between the reference span time of the non-zero comparison pulse and the reference span time of the zero-crossing comparison pulse, and using it as the fourth difference; obtaining two consecutive fourth differences, and determining the difference between the second fourth difference and the first fourth difference, as the third target difference; if the third target difference is greater than or equal to the third preset difference threshold, determining that the response voltage wave has attenuated; if the third target difference is less than the third preset difference threshold, determining that the response voltage wave has not attenuated.

[0128] Among them, the difference between the reference span time of each non-zero comparison pulse and the reference span time of the corresponding zero-crossing comparison pulse can be determined as the fourth difference, that is, the number of fourth differences is multiple. Then, two consecutive fourth differences can be determined, and the two fourth differences are sorted in time order, and the difference between the second fourth difference and the first fourth difference in the two consecutive fourth differences is determined as the third target difference; once the third target difference is greater than or equal to the third preset difference threshold, it is determined that the response voltage wave is attenuated, and if the third target difference is less than the third preset difference threshold, it is determined that the response voltage wave is not attenuated.

[0129] For example, TD_NZ_PZ[N]=TS_NZ[N]-TS_PZ[N], wherein TS_NZ[N] represents the reference span time of the Nth non-zero comparison pulse, TS_PZ[N] represents the reference span time of the Nth zero-crossing comparison pulse, and TD_NZ_PZ[N] represents the fourth difference value;

[0130] TD_B1[N]=TD_NZ_PZ[N]-TD_NZ_PZ[N-1], where TD_B1[N] represents the third target difference.

[0131] It should be noted that the third preset difference threshold is set according to actual needs, and the specific value of the third preset difference threshold is not limited in the embodiment of the present application.

[0132] In addition, in the embodiment of the present application, when the third target difference is greater than the third preset difference threshold, it is determined that the response voltage wave is attenuated, and when the third target difference is less than or equal to the third preset difference threshold, it is determined that the response voltage wave is not attenuated.

[0133] In some implementations, the implementation method for determining whether the response voltage wave is attenuated based on the first reference span time and the second reference span time can be: determining the pulse span time of the non-zero comparison pulse based on the reference span time of the non-zero comparison pulse and the reference span time of the zero-crossing comparison pulse; determining the pulse span time of two consecutive non-zero comparison pulses, and determining the difference between the pulse span time of the second non-zero comparison pulse and the pulse span time of the first non-zero comparison pulse, and using it as the fourth target difference; if the fourth target difference is less than the fourth preset difference threshold, determining that the response voltage wave is attenuated; if the fourth target difference is greater than or equal to the fourth preset difference threshold, determining that the response voltage wave is not attenuated.

[0134] For example, TD_B2[N]=TS_NZP[N]-TS_NZP[N-1], where TS_NZP[N] represents the pulse span time of the Nth non-zero comparison pulse, TS_NZP[N-1] represents the pulse span time of the N-1th non-zero comparison pulse, and TD_B2[N] represents the fourth target difference.

[0135] It should be noted that the fourth preset difference threshold is set according to actual needs, and the specific value of the fourth preset difference threshold is not limited in the embodiment of the present application.

[0136] In addition, in the embodiment of the present application, when the fourth target difference is less than or equal to the fourth preset difference threshold, it is determined that the response voltage wave is attenuated; when the fourth target difference is greater than the fourth preset difference threshold, it is determined that the response voltage wave is not attenuated.

[0137] In some implementations, based on the reference span time of the non-zero comparison pulse and the reference span time of the zero-crossing comparison pulse, the pulse span time of the non-zero comparison pulse can be determined by: determining the difference between the reference span time of the non-zero comparison pulse corresponding to the response voltage wave and the reference span time of the zero-crossing comparison pulse, and taking it as the fourth difference; based on the fourth difference, determining the pulse span time of the non-zero comparison pulse.

[0138] For example, TD_NZ_PZ[N]=TS_NZ[N]-TS_PZ[N], wherein TS_NZ[N] represents the reference span time of the Nth non-zero comparison pulse, TS_PZ[N] represents the reference span time of the Nth zero-crossing comparison pulse, and TD_NZ_PZ[N] represents the fourth difference.

[0139] In some implementations, determining the pulse span time of the non-zero comparison pulse based on the fourth difference includes: subtracting half of the initial period of the initial pulse group from twice the fourth difference to obtain the pulse span time of the non-zero comparison pulse.

[0140] For example, TS_NZP[N]=Tip / 2-TD_NZ_PZ[N]*2, wherein Tip represents the pulse period of the initial pulse group, NZ_PZ[N] represents the Nth fourth difference value, and TS_NZP[N] represents the pulse span time of the Nth non-zero comparison pulse.

[0141] Step 704: When the attenuation of the response voltage wave is greater than or equal to the preset attenuation threshold, stop measuring the acoustic wave transit time of the acoustic wave group, and determine the acoustic wave transit time of the acoustic wave group based on the second reference span time.

[0142] Among them, once the attenuation of the response voltage wave is greater than or equal to the preset attenuation threshold, it indicates that the initial pulse group has stopped transmitting, the last sound wave of the sound wave group emitted by the excitation transducer has reached the receiving transducer, and the receiving transducer has completed the response and begins to decay, thereby stopping the measurement of the sound wave transit time of the sound wave group, and then the sound wave transit time of the sound wave group can be determined based on the reference span time of the zero-crossing comparison pulse, that is, the sound wave transit time of the sound wave group can be determined based on the second reference span time. Among them, the determination of the sound wave transit time of the sound wave group based on the second reference span time can be determined by referring to the method in the relevant technology, which will not be repeated here.

[0143] It should be noted that in the embodiment of the present application, regarding the comparison with the threshold, the judgment is made by being greater than or equal to the threshold and less than the threshold, which clarifies the principle of the present application. Of course, regarding the comparison with the threshold, the judgment can also be made by being greater than the threshold and less than or equal to the threshold. Regarding the comparison with the threshold, the judgment can also be made by being greater than the threshold and less than the threshold. In this regard, the embodiment of the present application is not limited. Among them, for example, when the third target difference is greater than the third preset difference threshold, it is determined that the response voltage wave is attenuated, and when the third target difference is less than or equal to the third preset difference threshold, it is determined that the response voltage wave is not attenuated. By comparing in this way, it is also possible to determine that the response voltage wave is attenuated when the third target difference is greater than or equal to the third preset difference threshold, and determine that the response voltage wave is not attenuated when the third target difference is less than the third preset difference threshold. It is also possible to determine that the response voltage wave is attenuated when the third target difference is greater than the third preset difference threshold, and determine that the response voltage wave is not attenuated when the third target difference is less than the third preset difference threshold.

[0144] An embodiment of the present application provides a device, which includes the device for measuring the acoustic wave transit time in any of the above embodiments.

[0145] It should be noted that the equipment in the embodiments of the present application includes but is not limited to vehicles, ships, submarines, water meters, heat meters, gas meters, oil meters, flow meters, etc.

[0146] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0147] Although the embodiments of the present application have been shown and described, those skilled in the art will appreciate that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present application, and that the scope of the present application is defined by the claims and their equivalents.

Claims

1. A device for measuring the acoustic wave transit time, characterized in that: The acoustic wave transit time measuring device comprises: a control module, a pulse generating unit, a transducer assembly, a first span time measuring unit, a second span time measuring unit, a first comparator and a second comparator; The first span time measurement unit, the second span time measurement unit, and the pulse generation unit are all electrically connected to the control module; the pulse generation unit is electrically connected to the transducer assembly, the first span time measurement unit, and the second span time measurement unit, respectively; the transducer assembly is electrically connected to the first comparator and the second comparator, respectively; the first comparator is electrically connected to the first span time measurement unit, and the second comparator is electrically connected to the second span time measurement unit; The pulse generating unit is used to generate and output a periodic initial pulse group, the transducer assembly is used to generate and transmit a sound wave group when receiving the initial pulse group, and the transducer assembly is also used to generate a response voltage wave group when receiving the sound wave group, and the response voltage wave group can be transmitted to the first comparator and the second comparator; The first comparator is used to perform non-zero comparison and output a non-zero comparison pulse signal to the first span time measurement unit, and the second comparator is used to perform zero-crossing comparison, or first perform non-zero comparison and then perform zero-crossing comparison, and output a zero-crossing comparison pulse signal to the second span time measurement unit; the first span time measurement unit is used to measure the reference span time of the non-zero comparison pulse to obtain its measurement value and send it to the control module, and the second span time measurement unit is used to measure the reference span time of the zero-crossing comparison pulse to obtain its measurement value and send it to the control module; The control module is used to determine the reference span time of the non-zero comparison pulse according to the measured value of the reference span time of the non-zero comparison pulse, and determine the reference span time of the zero-crossing comparison pulse according to the measured value of the reference span time of the zero-crossing comparison pulse, and determine whether the response voltage wave is attenuated according to the reference span time of the non-zero comparison pulse, and when the attenuation of the response voltage wave is greater than or equal to a preset attenuation threshold, stop measuring the sound wave flight time of the sound wave group, and determine the sound wave flight time of the sound wave group based on the reference span time of the zero-crossing comparison pulse.

2. The device for measuring the acoustic wave transit time according to claim 1, characterized in that: The device for measuring the acoustic wave transit time also includes a pulse counting unit; The pulse counting unit is electrically connected to the control module and the first comparator respectively, and is used to count the number of non-zero comparison pulse signals transmitted to the pulse counting unit, and transmit the counted number of non-zero comparison pulse signals to the control module.

3. The device for measuring the acoustic wave transit time according to claim 1, characterized in that: The device for measuring the acoustic wave flight time also includes an analog gate; The analog gate is electrically connected to the pulse generating unit and the transducer assembly, and is electrically connected to the first comparator and the second comparator. The analog gate is switched on so that the excitation voltage wave group corresponding to the initial pulse group emitted by the pulse generating unit is transmitted to the first comparator and the second comparator, or the response voltage wave group generated by the transducer assembly is transmitted to the first comparator and the second comparator.

4. The device for measuring the acoustic wave transit time according to claim 1, characterized in that: The device for measuring the acoustic wave transit time further comprises a first output buffer and a second output buffer, and the transducer assembly comprises a first transducer and a second transducer; The first output buffer is electrically connected to the pulse generating unit and the first transducer respectively, and the second output buffer is electrically connected to the pulse generating unit and the second transducer respectively; One of the first transducer and the second transducer serves as an excitation transducer, and the other serves as a response transducer. When the first output buffer is configured as an output state and the second output buffer is configured as a cut-off state, the first output buffer provides an excitation voltage and a current to the first transducer, so that the first transducer serves as an excitation transducer and the second transducer serves as a response transducer. The first transducer generates and transmits a sound wave group, the second transducer receives the sound wave group and generates a response voltage wave group, and the response transducer is electrically connected to the comparator. When the second output buffer is configured as an output state and the first output buffer is configured as a cut-off state, the second output buffer provides an excitation voltage and a current to the second transducer, so that the second transducer serves as an excitation transducer and the first transducer serves as a response transducer. The second transducer generates and transmits a sound wave group, the first transducer receives the sound wave group and generates a response voltage wave group, and the response transducer is electrically connected to the comparator.

5. The device for measuring the acoustic wave transit time according to claim 4, characterized in that: The device for measuring the acoustic wave transit time also includes a measuring tube; One of the first transducer and the second transducer is disposed at the first end of the measuring tube, and the other is disposed at the second end of the measuring tube.

6. The device for measuring the acoustic wave transit time according to claim 1, characterized in that: The device for measuring the acoustic wave transit time further comprises a third output buffer, and the transducer assembly comprises a third transducer; The third output buffer is electrically connected to the pulse generating unit and the third transducer respectively.

7. The device for measuring the acoustic wave transit time according to claim 1, characterized in that: The device for measuring the acoustic wave transit time further comprises a reference voltage generating component, wherein the reference voltage generating component is electrically connected to the first comparator and the second comparator respectively, and the reference voltage generating component is used to transmit a reference voltage to the first comparator and the second comparator.

8. The device for measuring the acoustic wave transit time according to claim 1, characterized in that: The device for measuring the acoustic wave transit time further comprises a first coupling capacitor and a second coupling capacitor, and the transducer assembly comprises a first transducer and a second transducer; The first coupling capacitor is electrically connected to the first transducer, and the second coupling capacitor is electrically connected to the second transducer; Wherein, when the first transducer acts as a response transducer, the first coupling capacitor is used to couple the response voltage of the first transducer to the first comparator and the second comparator; when the second transducer acts as a response transducer, the second coupling capacitor is used to couple the response voltage of the second transducer to the first comparator and the second comparator.

9. The device for measuring the acoustic wave transit time according to claim 1, characterized in that: The device for measuring the acoustic wave transit time further comprises a third coupling capacitor, and the transducer assembly comprises a third transducer; The third coupling capacitor is electrically connected to the third transducer; Wherein, when the third transducer is used as a response transducer, the third coupling capacitor is used to couple the response voltage of the third transducer to the first comparator and the second comparator.

10. A method for measuring acoustic wave transit time, characterized in that: Applicable to the device for measuring the acoustic wave transit time as described in any one of claims 1 to 9, the measuring method comprises: Acquire a first measurement value of the first span time measurement unit and a second measurement value of the second span time measurement unit, wherein the first measurement value includes a measurement value of a reference span time of a non-zero comparison pulse, and the second measurement value includes a measurement value of a reference span time of a zero-crossing comparison pulse; Determine a reference span time of a non-zero comparison pulse based on the first measurement value and use it as a first reference span time, and determine a reference span time of a zero-crossing comparison pulse based on the second measurement value and use it as a second reference span time; determining whether the response voltage wave is attenuated based on the first reference span time; When the attenuation amount of the response voltage wave is greater than or equal to a preset attenuation threshold, the measurement of the acoustic wave transit time of the acoustic wave group is stopped, and the acoustic wave transit time of the acoustic wave group is determined based on the second reference span time.

11. The method for measuring the acoustic wave transit time according to claim 10, characterized in that: The step of determining whether the response voltage wave is attenuated based on the first reference span time includes: Determine the reference span time of three consecutive non-zero comparison pulses, and the reference span time of the three non-zero comparison pulses are arranged in time sequence; Determine a difference between a reference span time of the third non-zero comparison pulse and a reference span time of the second non-zero comparison pulse as a first difference, determine a difference between a reference span time of the second non-zero comparison pulse and a reference span time of the first non-zero comparison pulse as a second difference; Determine a difference between the first difference and the second difference and use the difference as a first target difference; If the first target difference is greater than or equal to the first preset difference threshold, it is determined that the response voltage wave is attenuated; if the first target difference is less than the first preset difference threshold, it is determined that the response voltage wave is not attenuated.

12. The method for measuring the acoustic wave transit time according to claim 11, characterized in that: Before determining the reference span time of three consecutive non-zero comparison pulses, the method for measuring the acoustic wave flight time further includes: Determine a reference span time of two consecutive non-zero comparison pulses, wherein the reference span times of the two non-zero comparison pulses are sequentially arranged in chronological order; determining a difference between a reference span time of the second non-zero comparison pulse and a reference span time of the first non-zero comparison pulse, and using the difference as a third difference; Determine a difference between the third difference and the pulse period of the initial pulse group and use it as a second target difference; If the second target difference is less than the second preset difference threshold, the reference span times of three consecutive non-zero comparison pulses are determined starting from the reference span time of the first non-zero comparison pulse.

13. The method for measuring the acoustic wave transit time according to claim 10, characterized in that: The step of determining whether the response voltage wave is attenuated based on the first reference span time includes: Based on the first reference span time and the second reference span time, it is determined whether the response voltage wave is attenuated.

14. The method for measuring the acoustic wave transit time according to claim 13, characterized in that: The determining whether the response voltage wave is attenuated based on the first reference span time and the second reference span time includes: Determine a difference between a reference span time of the non-zero comparison pulse and a reference span time of the zero-crossing comparison pulse, and use the difference as a fourth difference; Obtaining two consecutive fourth difference values, and determining a difference between the second fourth difference value and the first fourth difference value as a third target difference value; If the third target difference is greater than or equal to the third preset difference threshold, it is determined that the response voltage wave is attenuated; if the third target difference is less than the third preset difference threshold, it is determined that the response voltage wave is not attenuated.

15. The method for measuring the acoustic wave transit time according to claim 13, characterized in that: The determining whether the response voltage wave is attenuated based on the first reference span time and the second reference span time includes: Determining a pulse span time of the non-zero comparison pulse based on a reference span time of the non-zero comparison pulse and a reference span time of the zero-crossing comparison pulse; Determine the pulse span time of two consecutive non-zero comparison pulses, and determine the difference between the pulse span time of the second non-zero comparison pulse and the pulse span time of the first non-zero comparison pulse, and use it as the fourth target difference; If the fourth target difference is less than the fourth preset difference threshold, it is determined that the response voltage wave is attenuated; if the fourth target difference is greater than or equal to the fourth preset difference threshold, it is determined that the response voltage wave is not attenuated.

16. The method for measuring the acoustic wave transit time according to claim 14, characterized in that: The step of determining the pulse span time of the non-zero comparison pulse based on the reference span time of the non-zero comparison pulse and the reference span time of the zero-crossing comparison pulse comprises: Determine a difference between a reference span time of the non-zero comparison pulse corresponding to the response voltage wave and a reference span time of the zero-crossing comparison pulse, and use the difference as a fourth difference; Based on the fourth difference, a pulse span time of the non-zero comparison pulse is determined.

17. The method for measuring the acoustic wave transit time according to claim 16, characterized in that: The step of determining the pulse span time of the non-zero comparison pulse based on the fourth difference value comprises: The pulse span time of the non-zero comparison pulse is obtained by subtracting one half of the pulse period of the initial pulse group from twice the fourth difference value.

18. A device, characterized in that The device comprises the device for measuring the acoustic wave transit time according to any one of claims 1-9.

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