阅读说明：本技术 一种消声电路以及声波式水位监测设备 (Noise elimination circuit and sound wave type water level monitoring equipment ) 是由 徐乐华 戈燕红 谢广群 于 2019-09-29 设计创作，主要内容包括：本发明实施例公开了一种消声电路及声波式水位监测设备,消声电路包括单片机以及H桥驱动模块,H桥驱动模块包括信号缓冲器、双路电机H桥驱动电路、喇叭以及过载断路检测电路；所述信号缓冲器与所述单片机电连接并接收来自所述单片机的驱动信号以及消声信号；所述双路电机H桥驱动电路分别与所述信号缓冲器以及所述喇叭电连接；所述过载断路检测电路分别与所述喇叭以及所述单片机电连接。通过应用本发明的技术方案提出的消声电路,可有效抑制喇叭在驱动(发声振动)之时音圈所产生的振荡波,减小声波在经过导波管、声环及折弯传输时引起的波形叠加、振荡,大大提高了声波在软件算法中的可识别性。特别是在远距离、多折弯等复杂工况下尤其明显。(The embodiment of the invention discloses a silencing circuit and sound wave type water level monitoring equipment, wherein the silencing circuit comprises a single chip microcomputer and an H-bridge driving module, and the H-bridge driving module comprises a signal buffer, a double-path motor H-bridge driving circuit, a loudspeaker and an overload circuit break detection circuit; the signal buffer is electrically connected with the single chip microcomputer and receives a driving signal and a silencing signal from the single chip microcomputer; the double-circuit motor H-bridge driving circuit is electrically connected with the signal buffer and the horn respectively; the overload disconnection detection circuit is electrically connected with the horn and the singlechip respectively. By applying the noise elimination circuit provided by the technical scheme of the invention, the oscillation wave generated by the voice coil when the loudspeaker is driven (sound vibration) can be effectively inhibited, the waveform superposition and oscillation caused by the transmission of the sound wave through the waveguide tube, the sound ring and the bending are reduced, and the identifiability of the sound wave in a software algorithm is greatly improved. Especially under the complex working conditions of long distance, multiple bending and the like.)

1. The utility model provides a noise elimination circuit, includes singlechip and H bridge drive module, its characterized in that: the H-bridge driving module comprises a signal buffer, a double-path motor H-bridge driving circuit, a loudspeaker and an overload circuit break detection circuit; the signal buffer is electrically connected with the single chip microcomputer and receives a driving signal and a silencing signal from the single chip microcomputer; the double-circuit motor H-bridge driving circuit is electrically connected with the signal buffer and the horn respectively; the overload disconnection detection circuit is electrically connected with the horn and the singlechip respectively.

2. The muffling circuit of claim 1, wherein the single-chip microcomputer comprises a drive signal output pin and a muffling signal output pin; the signal buffer comprises a driving signal input pin and a silencing signal input pin; the driving signal output pin is electrically connected with the driving signal input pin; the silencing signal output pin is electrically connected with the silencing signal input pin.

3. The muffling circuit of claim 2, wherein the drive signal output pin is electrically connected to the drive signal input pin through a first current limiting resistor.

4. The muffling circuit of claim 3, wherein the muffling signal output pin is electrically connected to the muffling signal input pin through a second current limiting resistor.

5. The muffling circuit of claim 4, wherein the drive signal input pin is grounded through a first ground resistor.

6. The muffling circuit of claim 5, wherein the muffled signal input pin is grounded through a second ground resistor.

7. The muffling circuit of claim 6, wherein the signal buffer comprises a drive buffered signal output pin and a muffling buffered signal output pin; the double-circuit motor H-bridge driving circuit comprises a bidirectional motor driving chip, wherein the bidirectional motor driving chip comprises a driving buffer signal input pin and a silencing buffer signal input pin; the driving buffer signal output pin is electrically connected with the driving buffer signal input pin; the noise elimination buffering signal output pin is electrically connected with the noise elimination buffering signal input pin.

8. The muffling circuit of claim 7, wherein the drive buffer signal output pin is grounded through a third ground resistor; and the silencing buffer signal output pin is grounded through a fourth grounding resistor.

9. The muffling circuit of claim 8, wherein the overload trip detection circuit comprises a signal amplifier and a sampling resistor, the signal amplifier being electrically connected to the horn through the sampling resistor.

10. An acoustic water level monitoring apparatus, comprising a sound damping circuit as claimed in any one of claims 1 to 9.

Technical Field

The invention relates to the technical field of water level monitoring, in particular to a noise elimination circuit and sound wave type water level monitoring equipment.

Background

Since the country carries out 'river growth control', rivers and lakes to be monitored are strange, and compared with the traditional ultrasonic series water level monitoring products, the acoustic wave type monitoring has the advantages of stronger working condition adaptability, lower construction and maintenance cost and the like. The device is particularly obvious under the severe working conditions of installation points of dams, lakes and the like, and has the characteristics of difficult maintenance and restoration, expensive consumable articles and the like of pressure type water level meters, bubble type water level meters and the like because the device does not need to be vertically installed like products such as ultrasonic waves, floats, radars and the like.

The existing acoustic wave type water level monitoring products are generally influenced by temperature, waveguide tube switching (various platforms, bending, and bending), and the like, so that the problems of large noise, acoustic wave oscillation superposition deformation and the like in the transmission process of acoustic waves are solved, software cannot effectively distinguish when acquiring acoustic wave signals, the problems of low measurement precision, small measurement distance and the like are caused, and the existing acoustic wave type water level monitoring products cannot be compared with other ultrasonic series products.

Disclosure of Invention

The technical problem to be solved by the embodiment of the invention is how to improve the measurement precision of the acoustic wave type water level monitoring product.

In order to solve the above problems, in a first aspect, an embodiment of the present invention provides a noise cancellation circuit, where the noise cancellation circuit includes a single chip and an H-bridge driving module, and the H-bridge driving module includes a signal buffer, a two-way motor H-bridge driving circuit, a horn, and an overload disconnection detection circuit; the signal buffer is electrically connected with the single chip microcomputer and receives a driving signal and a silencing signal from the single chip microcomputer; the double-circuit motor H-bridge driving circuit is electrically connected with the signal buffer and the horn respectively; the overload disconnection detection circuit is electrically connected with the horn and the singlechip respectively.

The further technical scheme is that the single chip microcomputer comprises a driving signal output pin and a silencing signal output pin; the signal buffer comprises a driving signal input pin and a silencing signal input pin; the driving signal output pin is electrically connected with the driving signal input pin; the silencing signal output pin is electrically connected with the silencing signal input pin.

The further technical scheme is that the driving signal output pin is electrically connected with the driving signal input pin through a first current limiting resistor.

The noise elimination signal output pin is electrically connected with the noise elimination signal input pin through a second current limiting resistor.

The further technical scheme is that the driving signal input pin is grounded through a first grounding resistor.

The technical scheme is that the noise elimination signal input pin is grounded through a second grounding resistor.

The signal buffer comprises a driving buffer signal output pin and a silencing buffer signal output pin; the double-circuit motor H-bridge driving circuit comprises a bidirectional motor driving chip, wherein the bidirectional motor driving chip comprises a driving buffer signal input pin and a silencing buffer signal input pin; the driving buffer signal output pin is electrically connected with the driving buffer signal input pin; the noise elimination buffering signal output pin is electrically connected with the noise elimination buffering signal input pin.

The further technical scheme is that the driving buffer signal output pin is grounded through a third grounding resistor; and the silencing buffer signal output pin is grounded through a fourth grounding resistor.

The overload disconnection detection circuit comprises a signal amplifier and a sampling resistor, wherein the signal amplifier is electrically connected with the loudspeaker through the sampling resistor.

In a second aspect, an embodiment of the present invention provides an acoustic wave water level monitoring apparatus, which includes the muffling circuit according to the first aspect.

By applying the noise elimination circuit provided by the technical scheme of the invention, the oscillation wave generated by the voice coil when the loudspeaker is driven (sound vibration) can be effectively inhibited, the waveform superposition and oscillation caused by the transmission of the sound wave through the waveguide tube, the sound ring and the bending are reduced, and the identifiability of the sound wave in a software algorithm is greatly improved. Especially under the complex working conditions of long distance, multiple bending and the like.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

Fig. 1 is a circuit diagram of an H-bridge driving module of a noise cancellation circuit according to an embodiment of the present invention;

fig. 2 is a schematic diagram of a single chip of a noise elimination circuit according to an embodiment of the present invention;

fig. 3 is a circuit diagram of a receiving amplifying circuit according to an embodiment of the present invention;

fig. 4 is a diagram of sound wave signals collected after the application of the noise elimination circuit according to the embodiment of the present invention;

fig. 5 is a diagram of another sound wave signal collected after the application of the noise elimination circuit according to the embodiment of the present invention;

FIG. 6 is a schematic view illustrating an installation of an acoustic wave water level monitoring apparatus according to an embodiment of the present invention;

fig. 7 is a schematic structural diagram of a waveguide of an acoustic water level monitoring apparatus according to an embodiment of the present invention.

Detailed Description

The technical solutions in the embodiments will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, wherein like reference numerals represent like elements in the drawings. It is apparent that the embodiments to be described below are only a part of the embodiments of the present invention, and not all of them. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

It will be understood that the terms "comprises" and/or "comprising," when used in this specification and the appended claims, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.

It is also to be understood that the terminology used in the description of the embodiments of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the embodiments of the invention. As used in the description of embodiments of the present invention and the appended claims, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise.

Referring to fig. 1 to 3, an embodiment of the present invention provides a noise elimination circuit, and as can be seen from the figures, the noise elimination circuit includes a single chip microcomputer U5 and an H-bridge driving module. And the single chip microcomputer U5 is respectively and electrically connected with the receiving and amplifying circuit and the H-bridge driving module. In the present embodiment, the H-bridge driving module includes a signal buffer U2, a two-way motor H-bridge driving circuit 10, a horn LS2, and an overload trip detection circuit 20. In this embodiment, the sampling signal is subjected to dynamic gain adjustment by a receiving and amplifying circuit and preset software, and then sent to an ADC pin of the single chip microcomputer U5 for data acquisition. The signal buffer U2 is electrically connected with the singlechip U5 and receives a driving signal and a silencing signal from the singlechip U5; the double-circuit motor H bridge driving circuit 10 is respectively and electrically connected with a signal buffer U2 and a horn LS 2; the overload circuit breaking detection circuit 20 is electrically connected with the horn LS2 and the single chip microcomputer U5 respectively.

By applying the silencing circuit provided by the technical scheme of the invention, the preset software is used for controlling and driving the double-circuit motor H-bridge driving circuit to achieve the motor braking effect, the oscillation wave generated by the voice coil when the loudspeaker is driven (sound vibration) can be effectively inhibited, the waveform superposition and oscillation caused by the transmission of redundant oscillation wave through the waveguide tube, the sound ring and the bend are reduced, and the identifiability of the sound wave in a software algorithm is greatly improved. Especially under the complex working conditions of long distance, multiple bending and the like.

Specifically, the single chip microcomputer U5 comprises a driving signal output pin PB3/JTDO and a silencing signal output pin PA 15/JTDI. The signal buffer U2 includes a driving signal input pin 1A, a noise elimination signal input pin 3A, a driving buffer signal output pin 6Y, and a noise elimination buffer signal output pin 4Y. The two-way motor H-bridge driving circuit 10 comprises a two-way motor driving chip U3, and the two-way motor driving chip U3 comprises a driving buffer signal input pin FI and a noise elimination buffer signal input pin BI.

The drive signal output pin PB3/JTDO of the singlechip U5 is electrically connected with the drive signal input pin 1A of the signal buffer U2, and the singlechip U5 outputs a drive signal to the signal buffer U2 through the drive signal output pin PB 3/JTDO.

A silencing signal output pin PA15/JTDI of the singlechip U5 is electrically connected with a silencing signal input pin 3A of the signal buffer U2; the singlechip U5 outputs a silencing signal to the signal buffer U2 through a silencing signal output pin PA 15/JTDI.

The drive buffer signal output pin 6Y of the signal buffer U2 is electrically connected to the drive buffer signal input pin FI of the bidirectional motor drive chip U3, and the signal buffer U2 outputs a drive buffer signal to the two-way motor H bridge drive circuit 10 through the drive buffer signal output pin 6Y.

The silencing buffer signal output pin 4Y of the signal buffer U2 is electrically connected with the silencing buffer signal input pin BI of the bidirectional motor driving chip U3, and the signal buffer U2 outputs a silencing buffer signal to the bidirectional motor driving chip U3 through the silencing buffer signal output pin 4Y.

The overload circuit-breaking detection circuit 20 comprises a signal amplifier U4 and a sampling resistor R7, wherein the signal amplifier U4 is electrically connected with the horn LS2 through the sampling resistor R7, and the signal amplifier U4 is also connected with a single chip microcomputer U5.

The driving signal input pin 1A of the signal buffer U2 is grounded through a first ground resistor R1. The noise-reduction signal input pin 3A of the signal buffer U2 is grounded through a second ground resistor R4. The drive buffer signal output pin 6Y of the signal buffer U2 is grounded through a third ground resistor R5. The noise elimination buffer signal output pin 4Y of the signal buffer U2 is grounded through a fourth ground resistor R6.

It should be noted that, in order to avoid the current from being too large, in this embodiment, the driving signal output pin PB3/JTDO of the single chip microcomputer U5 is electrically connected to the driving signal input pin 1A of the signal buffer U2 through the first current limiting resistor R2. And a silencing signal output pin PA15/JTDI of the singlechip U5 is electrically connected with a silencing signal input pin 3A of the signal buffer U2 through a second current limiting resistor R3.

By applying the noise elimination circuit provided by the technical scheme of the invention, the oscillation wave generated by the voice coil when the loudspeaker is driven (sound vibration) can be effectively inhibited, the waveform superposition and oscillation caused by the transmission of the sound wave through the waveguide tube, the sound ring and the bending are reduced, and the identifiability of the sound wave in a software algorithm is greatly improved. Especially under the complex working conditions of long distance, multiple bending and the like.

Since the horn generates oscillating waves to and fro due to the structure of the horn such as the elastic waves after the horn is driven to sound, the oscillating waves interfere with detection, and since the frequency of the sound waves is not as high as that of ultrasonic waves, the influence of the precision on the time axis is larger. And a multistage sound ring used for temperature compensation in the waveguide tube is added, so that the sound waves are rebounded and superposed when passing through the sound ring. In the embodiment of the invention, the silencing circuit generates two paths of driving signals through the singlechip, and the two paths of driving signals are amplified by the signal buffer and then sent to the bidirectional motor driving chip (an H bridge or a reversible H bridge driving module built by 4 paths of MOS (metal oxide semiconductor) tubes) to drive the loudspeaker. The H-bridge drive module can realize the effect of motor braking under the control of a preset software drive signal, and well control the residual vibration of the horn to eliminate stray waves. The H bridge drive module drives the loudspeaker by applying the principle of motor braking, drives the sound production by extremely narrow pulses, enables echoes to be in a state of tending to a single main peak, enables sound rings and liquid level waves to be distinguished in disordered echo sound easily by software, and effectively and quickly calculates the actual water level.

Referring to fig. 3, it should be further explained that the specific structure of the receiving amplifying circuit is well known to those skilled in the art and will not be described herein again.

Referring to fig. 4-5, fig. 4-5 are all sound wave signal diagrams acquired after the noise elimination circuit provided by the embodiment of the invention is applied, and it can be known that, after the noise elimination circuit provided by the embodiment of the invention is applied, the acquired sound wave signals have fewer clutters and the echoes tend to a single main peak state, so that the sound ring and the liquid level wave can be easily distinguished from the disordered echo sound in software, and the actual water level can be effectively and quickly calculated.

Referring to fig. 6 to 7, fig. 6 is an installation schematic diagram of an acoustic wave water level monitoring apparatus according to an embodiment of the present invention; fig. 7 is a schematic structural diagram of a waveguide of an acoustic water level monitoring apparatus according to an embodiment of the present invention. The embodiment of the invention provides sound wave type water level monitoring equipment which comprises a silencing circuit provided by the embodiment. The details of the noise cancellation circuit have been given in the above embodiments and will not be described herein.

In the above embodiments, the descriptions of the respective embodiments have respective emphasis, and for parts that are not described in detail in a certain embodiment, reference may be made to related descriptions of other embodiments.

It will be apparent to those skilled in the art that various changes and modifications may be made in the present invention without departing from the spirit and scope of the invention. Thus, while the invention has been described with respect to the above-described embodiments, it will be understood that the invention is not limited thereto but may be embodied with various modifications and changes.

While the invention has been described with reference to specific embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.