Ultrasonic transducer signal transmitting and receiving switching circuit and ultrasonic metering module

Abstract

The utility model discloses an ultrasonic transducer signal transmitting and receiving switching circuit, which comprises a signal transmitting module, an ultrasonic sensor A, an ultrasonic sensor B and a signal receiving module, and is characterized in that the ultrasonic sensor A is electrically connected with the signal transmitting module through a first analog switch group and a third analog switch group; the ultrasonic sensor B is electrically connected with the signal transmitting module through a second analog switch group and a fourth analog switch group; the ultrasonic sensor A is electrically connected with the signal receiving module through the first analog switch group and the fifth analog switch group, and the ultrasonic sensor B is electrically connected with the signal receiving module through the second analog switch group and the sixth analog switch group. The receiving and transmitting switching circuit suppresses the problem of receiving channel coupling in a manner of consuming an interference signal coupled by an analog switch through grounding.

Description

TECHNICAL FIELD

[0001] The utility model relates to ultrasonic measurement technical field, more particularly to a kind of ultrasonic transducer signal transceiving switching circuit and ultrasonic measurement module. BACKGROUND

[0002] Flow measurement using ultrasonic wave has the advantages of wide range, high precision, maintenance-free, etc., and time difference method is a typical ultrasonic flow measurement method, which measures the time of sound wave propagation in flowing medium in downstream and upstream respectively to calculate the average flow rate of fluid, and then multiplies the cross-sectional area of flow passage to obtain the flow rate of fluid. The time difference method flow measurement circuit is generally composed of controller, pulse generator, driver, switching switch, transducer, transceiving switching circuit, amplifier, comparator, timing unit and processor, etc., as shown in FIG. 1. Because the transmission time in downstream and upstream directions needs to be measured, two transducers are used as both ultrasonic pulse transmitter and receiver, so transceiving switching circuit is needed to realize transceiving switching during downstream and upstream measurement. Figure 1

[0003] The conventional transceiving switching circuit uses analog switch to switch transceiving state, as shown in FIG. 2, the common terminals of two single-pole double-throw analog switches are connected to two transducers respectively, the normally closed terminal of switch S7 and the normally open terminal of switch S8 are connected to the transmission signal Fire of driver, and the normally open terminal of switch S7 and the normally closed terminal of switch S8 are connected to the input signal Receive of amplifier. Figure 2 Figure 2 In the state shown in FIG. 2, the signal is transmitted from U3 transducer, and U4 is in receiving state. When reverse direction measurement is needed, switch is switched to normally closed terminal by controlling direction signal Dir at the same time. Although this circuit can realize transceiving switching in downstream and upstream, because analog switch is not ideal switch, there are problems of off-isolation and cross-talk, which makes transmission signal coupled to receiving channel, and even affects the identification of normal signal when working frequency is high and signal is weak. Although the improved design of conventional transceiving switching circuit, such as ZL201822158329.7, reduces cross-talk to some extent, there is still a certain degree of cross-talk when signal is weak. SUMMARY

[0004] A series of simplified concepts are introduced in the content part of the utility model, which will be further described in detail in the specific embodiment part. The content part of the utility model does not mean to try to limit the key features and necessary technical features of the claimed technical solution, and even less means to determine the protection scope of the claimed technical solution.

[0005] ​​To at least partially solve the above problems, the utility model provides an ultrasonic transducer signal transceiving switching circuit, the transceiving switching circuit includes signal emission module, ultrasonic sensor A, ultrasonic sensor B and signal receiving module, ultrasonic sensor A is connected with signal emission module through first analog switch group, third analog switch group, ultrasonic sensor B is connected with signal emission module through second analog switch group, fourth analog switch group, ultrasonic sensor A is connected with signal receiving module through first analog switch group, fifth analog switch group, ultrasonic sensor B is connected with signal receiving module through second analog switch group, sixth analog switch group.

[0006] Preferably, the control mode of the fifth analog switch group and the sixth analog switch group is exclusive control of a direction switch and a receiving enable switch.

[0007] Preferably, the control mode of the first analog switch group, the second analog switch group, the third analog switch group and the fourth analog switch group is direction switch control.

[0008] Preferably, the control mode of the fifth analog switch group and the sixth analog switch group is exclusive control of a reverse direction switch and a receiving enable switch.

[0009] Preferably, the control mode of the first analog switch group and the second analog switch group is exclusive control of a direction switch and a receiving enable switch.

[0010] Preferably, the control mode of the third analog switch group and the fourth analog switch group is direction switch control.

[0011] Preferably, the signal receiving module comprises an amplifier, a comparator, a timing unit and a processor.

[0012] Preferably, the signal emission module comprises a controller, a pulse generator and a driver.

[0013] Preferably, the other end of the ultrasonic sensor A or the ultrasonic sensor B is grounded.

[0014] Preferably, the normally closed end of the fourth analog switch group is grounded.

[0015] Preferably, the normally closed end of the sixth analog switch group is grounded.

[0016] Preferably, the first analog switch group, the second analog switch group, the third analog switch group, the fourth analog switch group, the fifth analog switch group and the sixth analog switch group each comprise one analog switch or two analog switches, and the analog switch is one of a single-channel single-pole double-throw analog switch chip, a multi-channel single-pole double-throw analog switch chip or an integrated chip.

[0017] Preferably, the two signal ends of the ultrasonic sensor A are electrically connected with the signal transmitting module through the first analog switch group, the third analog switch group, the two signal ends of the ultrasonic sensor B are electrically connected with the signal transmitting module through the second analog switch group, the fourth analog switch group, the two signal ends of the ultrasonic sensor A are electrically connected with the signal receiving module through the first analog switch group, the fifth analog switch group, and the two signal ends of the ultrasonic sensor B are electrically connected with the signal receiving module through the second analog switch group, the sixth analog switch group.

[0018] An ultrasonic metering module comprising the ultrasonic transducer signal transceiving switching circuit according to any one of the preceding items.

[0019] The ultrasonic transducer signal transceiving switching circuit and the ultrasonic metering module have the following beneficial effects: the forward and reverse flow switching circuit uses six analog switch groups, adopts the measures of transmitting isolation grounding and receiving isolation grounding, can effectively reduce the crosstalk influence of the transmitting channel on the receiving channel, obviously improves the receiving signal quality near the transmitting signal, and significantly improves the signal-to-noise ratio in the case of weak signal and high amplification. BRIEF DESCRIPTION OF DRAWINGS

[0020] The following drawings of the utility model are used as a part of the utility model for understanding the utility model. The drawings show the embodiments of the utility model and the description thereof, and are used to explain the principle of the utility model.

[0021] In the drawings:

[0022] Figure 1 It is a time difference method flow measurement circuit schematic diagram in the background art of the utility model;

[0023] Figure 2 It is a conventional transceiving switching circuit schematic diagram in the background art of the utility model;

[0024] Figure 3 It is a schematic diagram of the ultrasonic transducer signal transceiving switching circuit provided by the first embodiment of the utility model;

[0025] Figure 4 It is a schematic diagram of the ultrasonic transducer signal transceiving switching circuit provided by the second embodiment of the utility model;

[0026] Figure 5 It is a schematic diagram of the ultrasonic transducer signal transceiving switching circuit provided by the third embodiment of the utility model;

[0027] Figure 6 It is a schematic diagram of the ultrasonic transducer signal transceiving switching circuit provided by the fourth embodiment of the utility model;

[0028] Figure 7 is a comparison chart of the received waveforms obtained at the receiving end of the conventional circuit and the circuit of the present patent. DETAILED DESCRIPTION

[0029] In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present application. It will be apparent, however, to one skilled in the art that the present application can be practiced without one or more of these specific details. In other instances, well-known features have not been described in detail so as not to unnecessarily obscure the present application.

[0030] In order to thoroughly understand the present application, detailed descriptions will be given in the following description. Obviously, the implementation of the embodiments of the present application is not limited to the special details familiar to those skilled in the art. The preferred embodiments of the present application are described in detail as follows, however, in addition to these detailed descriptions, the present application can also have other embodiments.

[0031] It should be noted that the terms used herein are only for the purpose of describing specific embodiments, and are not intended to limit the exemplary embodiments according to the present application. As used herein, the singular form is intended to include the plural form unless the context clearly indicates otherwise. In addition, it should be understood that when the terms "comprise" and / or "include" are used in the specification, it means that the stated features, integers, steps, operations, elements, and / or components exist, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or combinations thereof.

[0032] The ordinal numbers such as "first" and "second" cited in the present application are merely identifiers and do not have any other meaning, such as a specific order, etc. Moreover, for example, the term "first component" itself does not imply the existence of a "second component", and the term "second component" itself does not imply the existence of a "first component".

[0033] It should be noted that the terms "upper", "lower", "front", "rear", "left", "right", "inner", "outer", and similar expressions used herein are for illustrative purposes only and are not limiting.

[0034] Now, exemplary embodiments according to the present application will be described in greater detail with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in various different forms, and should not be interpreted as being limited to the embodiments set forth herein. It should be understood that these embodiments are provided so that the present disclosure is complete and complete, and the ideas of these exemplary embodiments are sufficiently conveyed to those skilled in the art.

[0035] Embodiment 1

[0036] Figure 3 The utility model provides a kind of schematic diagram of ultrasonic transducer signal transceiving switching circuit for embodiment one of the utility model, and the utility model is by the interference signal coupled by analog switch is consumed by ground in reverse, to suppress the problem of coupling of receiving channel.

[0037] An ultrasonic transducer signal transceiving switching circuit, the transceiving switching circuit includes signal transmitting module, ultrasonic sensor U1, ultrasonic sensor U2 and signal receiving module, the ultrasonic sensor U1 is electrically connected with the signal transmitting module by first analog switch group, third analog switch group, the ultrasonic sensor U2 is electrically connected with the signal transmitting module by second analog switch group, fourth analog switch group;The ultrasonic sensor U1 is electrically connected with the signal receiving module by first analog switch group, fifth analog switch group, and the ultrasonic sensor U2 is electrically connected with the signal receiving module by second analog switch group, sixth analog switch group.The control mode of the first analog switch group, second analog switch group, third analog switch group and fourth analog switch group is direction switch control.The control mode of the fifth analog switch group and sixth analog switch group is direction switch and receiving enable switch XOR control.

[0038] The normally closed end of the fourth analog switch group is grounded.The normally closed end of the sixth analog switch group is grounded.

[0039] The signal receiving module includes amplifier, comparator, timing unit and processor, and the signal transmitting module includes controller, pulse generator and driver.

[0040] As Figure 3 As shown in the utility model provides ultrasonic transducer signal transceiving switching circuit is composed of 6 single pole double throw analog switches.In the drawing, 1 terminal is normally closed end, 2 terminal is common end, 3 terminal is normally open end, normally closed and normally open are relative, and interchange is also established.

[0041] S1 and S2 are two transceiving switching analog switches, and the control mode is Dir direction switch control, and two common ends are connected to two transducers respectively, and the normally closed end 1 terminal of S1 and the normally open end 3 terminal of S2 are connected to the common end 2 terminal of transmitting analog switch S3 and the common end 2 terminal of S4 respectively, and the normally open end 3 terminal of S1 and the normally closed end 1 terminal of S2 are connected to the common end 2 terminal of receiving analog switch S5 and the common end 2 terminal of S6 respectively;

[0042] S3 and S4 are two analog switches for transmitting isolation, and the control mode is Dir direction switch control, and the normally closed end 1 terminal of S3 and the normally open end 3 terminal of S4 are connected to transmitting signal Fire, and the normally open end 3 terminal of S3 and the normally closed end 1 terminal of S4 are connected to GND.

[0043] S5 and S6 are two analog switches for receiving isolation, the control mode is Dir direction switch and Rcv_En receiving enable switch XOR control, the normally closed end 1 terminal of S5 and the normally open end 3 terminal of S6 are connected to the receiving signal Receive, the normally open end 3 terminal of S5 and the normally closed end 1 terminal of S6 are connected to GND;

[0044] The two signals of Dir direction switch control signal and Rcv_En receiving enable switch signal are used to control the transceiver switch simultaneously, wherein the control end of S1 / S2 / S3 / S4 is controlled by Dir direction switch, and S5 / S6 is controlled by the XOR value of Dir direction switch and Rcv_En receiving enable switch. The specific control mode is as follows:

[0045]

[0046]

[0047] The transceiver switching circuit suppresses the coupling problem of the receiving channel by coupling the interference signal of the analog switch through the ground consumption.

[0048] Figure 3 In the transducer U1 is in the transmitting state, and the transducer U2 is in the receiving state.

[0049] (1) Fire is connected to the normally closed end 1 terminal of S3 and the normally open end 3 terminal of S4, when Fire works, the normally open end 3 terminal of S3 and the normally closed end 1 terminal of S4 will have coupled interference signals, at this time they are grounded, so the interference is greatly attenuated, even if a small amount of interference is conducted to the normally open end 3 terminal of S2, and then coupled to the normally closed end 1 terminal of S2, the interference is very small;

[0050] (2) Fire is connected to S1 through S3, during transmission, the normally open end 3 terminal of S1 will still be coupled to strong interference, S1 is connected to S5 and connected to the receiving amplifier circuit, at this time the interference can be effectively shielded through the time window, and will not affect the reception;

[0051] (3) During transmission, U2 in the receiving state is connected to S6 through S2, so as to realize grounding, even if there is interference in the transmitting circuit, it will not affect the receiving transducer;

[0052] (4) After the transmission is completed and a period of time t is delayed, before the receiving signal arrives, the Rcv_En receiving enable switch signal is adjusted, S5 / S6 is switched to the normally open end 3 terminal, at this time the receiving transducer U2 is connected to the Receive end, and is ready to receive the sound wave signal;

[0053] The time delay t is L / C, L is the sound path between the two transducers, and C is the propagation speed of sound in the medium.

[0054] (5) When switching direction, Dir is reversed, U2 is used as the transmitter, U1 is used as the receiver, and the mechanism of the ground consuming interference signals still holds.

[0055] Embodiment Two

[0056] Figure 4 A schematic diagram of an ultrasonic transducer signal transceiving switching circuit according to Embodiment Two of the present application is shown in the figure. The transceiving switching circuit comprises a signal transmitting module, an ultrasonic sensor U1, an ultrasonic sensor U2, and a signal receiving module. The ultrasonic sensor U1 is electrically connected to the signal transmitting module through a first analog switch group and a third analog switch group. The ultrasonic sensor U2 is electrically connected to the signal transmitting module through a second analog switch group and a fourth analog switch group. The ultrasonic sensor U1 is electrically connected to the signal receiving module through a first analog switch group and a fifth analog switch group. The ultrasonic sensor U2 is electrically connected to the signal receiving module through a second analog switch group and a sixth analog switch group. The control mode of the fifth analog switch group and the sixth analog switch group is exclusive control of a reverse direction switch and a receiving enable switch. The control mode of the first analog switch group and the second analog switch group is exclusive control of a direction switch and a receiving enable switch. The control mode of the third analog switch group and the fourth analog switch group is direction switch control.

[0057] The flow measurement circuit needs to measure the propagation time of the sound wave from one transducer to another transducer, and needs to be set as a transmitting and receiving state respectively, while in the distance measurement application, the propagation time of the sound wave returned to the original transmitting transducer after reflection needs to be measured, and a certain transducer is required to be switched between transmitting and receiving states in time, i.e. to realize the self-transmitting and self-receiving function. The switching circuit of the present application can also realize the distance measurement mode, and the specific implementation mode is shown in Figure 4 .

[0058] The ultrasonic transducer signal transceiving switching circuit provided by the present application is composed of six single-pole double-throw analog switches. In the figure, the 1 terminal is a normally closed terminal, the 2 terminal is a common terminal, and the 3 terminal is a normally open terminal. The normally closed and normally open are relative, and the exchange is also established.

[0059] On the basis of the embodiment one, the control end of S1 / S2 analog switch is adjusted to the XOR value of Dir and Rcv_En to control, and the control end of S5 / S6 is adjusted to the XOR value of Dir after inversion and Rcv_En to control, and the control end of S3 / S4 remains unchanged, that is, the self-generation and self-reception function can be realized. Similar to the principle of the embodiment one, when U1 is used for transmission, S1 / S2 is in the normally closed end, U1 is in the transmission state, S5 / S6 is in the normally open end, and U2 is in the receiving state; before the receiving signal arrives, the Rcv_En signal is enabled, S1 / S2 is switched to the normally open end, S5 / S6 is switched to the normally closed end, at this time, U1 is in the receiving state, U2 is in the ground state, thereby realizing the self-generation and self-reception of U1. Setting Dir high can switch U2 to perform self-generation and self-reception. Although this embodiment does not separately design U1 to be grounded during non-transmission and receiving time, since the driving circuit itself has a grounding effect at the end of the transmission signal, this embodiment still has a strong inhibitory effect on the residual vibration of the transmission signal.

[0060] S1 and S2 are two transceiver switching analog switches, the control mode is Dir direction switch and Rcv_En receiving enable switch control, the two common ends are connected to two transducers U1 and U2 respectively, the normally closed end 1 terminal of S1 and the normally open end 3 terminal of S2 are connected to the common end 2 terminal of the transmission analog switch S3 and the common end 2 terminal of S4 respectively, the normally open end 3 terminal of S1 and the normally closed end 1 terminal of S2 are connected to the common end 2 terminal of the receiving analog switch S5 and the common end 2 terminal of S6 respectively;

[0061] S3 and S4 are two analog switches for transmission isolation, the control mode is Dir direction switch control, the normally closed end 1 terminal of S3 and the normally open end 3 terminal of S4 are connected to the transmission signal Fire, and the normally open end 3 terminal of S3 and the normally closed end 1 terminal of S4 are connected to GND;

[0062] S5 and S6 are two analog switches for receiving isolation, the control mode is XOR control of NOT (Dir) reverse direction switch and Rcv_En receiving enable switch, the normally closed end 1 terminal of S5 and the normally open end 3 terminal of S6 are connected to the receiving signal Receive, and the normally open end 3 terminal of S5 and the normally closed end 1 terminal of S6 are connected to GND;

[0063] The forward and reverse flow Dir direction switch control signal and the Rcv_En receiving enable switch signal are used to control the transceiver switching at the same time, wherein the control end of S3 / S4 is controlled by the Dir direction switch, S1 / S2 is controlled by the XOR value of the Dir direction switch and the Rcv_En receiving enable switch, and S5 / S6 is controlled by the XOR value of the NOT (Dir) reverse direction switch and the Rcv_En receiving enable switch. The specific control mode is:

[0064]

[0065] Figure 4 In the middle, transducer U1 is in the transmitting state, and transducer U2 is in the receiving state.

[0066] Fire transmits the driving signal transmitted by the signal transmitting module to the transducer U1 through the normally closed end 1 terminal of S3 and the normally closed end 1 terminal of S1, and the transducer U1 is excited to transmit an ultrasonic signal. In this process, the normally open end 3 terminal of S3 will be disturbed, and at the same time, the normally open end 3 terminal of S4 may transmit the driving signal to the normally closed end 1 terminal of S4, and the normally closed end 1 terminal of S4 and the normally open end 3 terminal of S3 reduce the interference signal by grounding. Even if the normally open end 3 terminal of S4 transmits the interference signal to the normally open end 3 terminal of S2, at this time the normally open end 3 terminal of S2 is suspended, the interference signal will also be reduced.

[0067] During transmission, U2 in the receiving state is connected to S6 through S2, so as to realize grounding, so that even if there is interference in the transmission circuit, the receiving transducer will not be affected;

[0068] After the transmission is completed and a time delay t is performed, before the receiving signal arrives, the Rcv_En receiving enable switch signal is adjusted, S5 / S6 is switched to the normally open end 3 terminal, at this time the receiving transducer U2 is connected to the Receive end, and is ready to receive the sound wave signal;

[0069] The time delay t is L / C, L is the sound path between the two transducers, and C is the propagation speed of sound in the medium.

[0070] When the direction is switched, the Dir is inverted, U2 is used as the transmitter, and U1 is used as the receiver, and the above interference signal grounding mechanism still holds;

[0071] As can be seen from the above specific control mode, whether it is transducer U1 or U2, the function of transmitting and receiving ultrasonic signals by itself can be realized, that is, the distance measuring function.

[0072] Embodiment three

[0073] Figure 5 A schematic diagram of an ultrasonic transducer signal transceiving switching circuit provided for the embodiment three of the utility model, the transceiving switching circuit includes a signal transmitting module, an ultrasonic sensor Transducer 11, an ultrasonic sensor Transducer 12 and a signal receiving module,

[0074] The ultrasonic sensor Transducer 11 is electrically connected with the signal transmitting module through the first analog switch group and the third analog switch group, and the ultrasonic sensor Transducer 12 is electrically connected with the signal transmitting module through the second analog switch group and the fourth analog switch group.

[0075] The ultrasonic sensor Transducer 11 is electrically connected with the signal receiving module through the first analog switch group and the fifth analog switch group, and the ultrasonic sensor Transducer 12 is electrically connected with the signal receiving module through the second analog switch group and the sixth analog switch group.

[0076] The first analog switch group, the second analog switch group, the third analog switch group, the fourth analog switch group, the fifth analog switch group and the sixth analog switch group each include one analog switch or two analog switches, and the analog switch is one of a single-channel single-pole double-throw analog switch chip, a multi-channel single-pole double-throw analog switch chip or an integrated chip.

[0077] Figure 5 It is a single-ended transceiver switching circuit scheme designed based on example 1, the first analog switch group, the second analog switch group, the third analog switch group, the fourth analog switch group, the fifth analog switch group and the sixth analog switch group each include one analog switch, respectively S11, S12, S13, S14, S15, S16, which are single-channel single-pole double-throw analog switch chips, and two signals Dir and Rcv_En are connected to the receiving analog switch control end through an exclusive OR gate chip.

[0078] Figure 5 In the transducer Transducer 11 is in the transmitting state, one end is electrically connected with S11, and the other end is grounded; the transducer Transducer 12 is in the receiving state, one end is electrically connected with S12, and the other end is grounded.

[0079] (1) Fire is connected with the normally closed end SB of S13 and the normally open end SA of S14, when Fire works, S11 and S13 are in the normally closed end SB, and the transducer Transducer 11 is in the transmitting state; the normally open end SA of S13 and the normally closed end SB of S14 will inevitably have coupled interference signals, at this time, their other ends are grounded, so that the interference signals are greatly attenuated, even if a small amount of interference is conducted to the normally open end SA of S12, at this time, the normally open end SA of S12 is suspended, so that the interference coupled to the normally closed end SB of S12 is very small;

[0080] (2) Fire is connected to S11 through S13, and the S11 always-open end SA will still be coupled to strong interference during emission, S11 is connected to S15 and connected to the receiving amplifier circuit, at this time the interference can be effectively shielded through the time window, and will not affect the reception;

[0081] (3) During emission, the transducer Transducer 12 in the receiving state is connected to S16 through S12, so as to realize grounding, and even if there is interference in the emission circuit, the receiving transducer will not be affected;

[0082] (4) After the emission is completed and a period of time t is delayed, before the receiving signal arrives, the Rcv_En signal is adjusted, S15 / S16 is switched to the always-open end SA, at this time the receiving transducer Transducer 12 is connected to the Receive end, and the ultrasonic wave emitted by the transducer Transducer 11 is received by the transducer Transducer 12 and then transmitted to the signal receiving module;

[0083] The delay time t is L / C, L is the sound path between the two transducers, and C is the propagation speed of sound in the medium.

[0084] Because of the delay for a period of time, the signal received by the transducer Transducer 12 is also affected by a small amount of interference signal.

[0085] (5) When the direction is switched, Dir is reversed, the transducer Transducer 12 is used as emission, and the transducer Transducer 11 is used as reception, and the above-mentioned interference signal grounding mechanism still holds.

[0086] Embodiment four

[0087] Figure 6 A schematic diagram of an ultrasonic transducer signal transceiving switching circuit provided by the fourth embodiment of the utility model, the transceiving switching circuit comprises a signal emission module, an ultrasonic sensor Transducer 21, an ultrasonic sensor Transducer 22 and a signal receiving module,

[0088] Two signal ends of the ultrasonic sensor Transducer 21 are electrically connected with the signal emission module through a first analog switch group and a third analog switch group, and two signal ends of the ultrasonic sensor Transducer 22 are electrically connected with the signal emission module through a second analog switch group and a fourth analog switch group;

[0089] The two signal ends of the ultrasonic sensor Transducer 21 are electrically connected with the signal receiving module through a first analog switch group and a fifth analog switch group, and the two signal ends of the ultrasonic sensor B are electrically connected with the signal receiving module through a second analog switch group and a sixth analog switch group.

[0090] In the scheme, the first analog switch group, the second analog switch group, the third analog switch group, the fourth analog switch group, the fifth analog switch group and the sixth analog switch group all include two analog switches.

[0091] Figure 6 The differential transceiver switching circuit scheme is provided by the utility model, and the two signal ends of the transducer are respectively connected to the respective transceiver switching / transmission isolation / reception isolation analog switch groups, the number of analog switches used is increased by one, and 12 analog switches are used.

[0092] Figure 6 In the scheme, the first analog switch group, the second analog switch group, the third analog switch group, the fourth analog switch group, the fifth analog switch group and the sixth analog switch group all include two analog switches.

[0093] (1) Fire is the superposition of two drive signals, and after signal analysis, is connected with the two normally closed ends of S23 and the two normally open ends of S24, when Fire works, S21 and S23 are in the normally closed end, and the transducer Transducer 21 transmits the superposition wave of two signals, during this period, the normally open end of S23 and the normally closed end of S24 will inevitably have a coupled interference signal, at this time, their other end is grounded, so that the interference signal is greatly attenuated, even if a small amount of interference is conducted to the normally open end of S22, at this time, the normally open end of S22 is suspended, so that the interference coupled to the normally closed end of S22 is very small;

[0094] (2) Fire is connected to S21 through S23, and the normally open end of S21 will still couple strong interference during transmission, S21 is connected to S25 and connected to the receiving amplification circuit, at this time, the interference can be effectively shielded through the time window, and will not affect the reception;

[0095] (3) During transmission, the transducer Transducer 22 in the receiving state is connected to S26 through S22, so as to realize grounding, even if there is interference in the transmission circuit, the receiving transducer will not be affected.

[0096] (4) After the emission and a period of time, before the arrival of the received signal, the Rcv_En signal is adjusted, S25 / S26 is switched to the normally open end S1B and S2B, at this time the receive transducer Transducer 22 is connected to the Receive end, the ultrasonic wave emitted by the transducer Transducer 21 is received by the transducer Transducer 22 and transmitted to the signal receiving module;

[0097] The delay time t=L / C, L is the sound path between the two transducers, and C is the propagation speed of sound in the medium.

[0098] Due to the delay for a period of time, the signal received by the transducer Transducer 22 is also less affected by the interference signal.

[0099] (5) When switching direction, Dir is inverted, the transducer Transducer 22 is used as emission, and the transducer Transducer 21 is used as reception, and the above interference signal consumption mechanism still holds;

[0100] The circuit arrangement mode of the first embodiment to the third embodiment can be used in the differential circuit of the fourth embodiment.

[0101] The first embodiment to the fourth embodiment only list the operation mode of the analog switch part operator, the utility model is not limited to the implementation mode mentioned in the above embodiment, any and the principle same implementation mode of the utility model is within the protection scope of the utility model.

[0102] Embodiment five

[0103] The utility model embodiment five still provides an ultrasonic wave metering module group, including the ultrasonic wave transducer signal transceiving switch circuit described in the first embodiment to the fourth embodiment.

[0104] Figure 7 It is the received waveform comparison chart obtained by the conventional circuit and the patent circuit in the receiving end, it can be seen that the patent waveform after high magnification, the clutter is less, still maintains the good signal to noise ratio.

[0105] Through the above description of the embodiments, those skilled in the art can clearly understand that the utility model can be realized by means of software and necessary general hardware, of course, it can also be realized by hardware, but in many cases, the former is a better embodiment. Based on such understanding, the technical scheme of the utility model can be embodied in the form of a software product in essence or in the part that contributes to the prior art, and the computer software product can be stored in a computer readable storage medium, such as a floppy disk, a read-only memory (ROM), a random access memory (RAM), a FLASH, a hard disk or an optical disk, etc., including a plurality of instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the method of each embodiment of the utility model.

[0106] It is worth noting that in the above embodiment of the ultrasonic transducer signal transceiving and switching circuit, each unit and module included is only divided according to functional logic, but is not limited to the above division, as long as the corresponding function can be realized; in addition, the specific name of each functional unit is only for easy mutual distinction, and does not limit the protection scope of the utility model.

[0107] Note that the above are only preferred embodiments of the utility model and the technical principles applied. Those skilled in the art will understand that the utility model is not limited to the specific embodiments here, and those skilled in the art can make various obvious changes, readjustments and substitutions without departing from the protection scope of the utility model. Therefore, although the utility model has been described in more detail through the above embodiments, the utility model is not limited to the above embodiments, and can include more other equivalent embodiments without departing from the utility model concept, and the scope of the utility model is determined by the appended claims.

Claims

1. An ultrasonic transceiver signal transmission and reception switching circuit, the transmission and reception switching circuit comprising a signal transmitting module, an ultrasonic sensor A, an ultrasonic sensor B, and a signal receiving module, characterized in that, The ultrasonic sensor A is electrically connected to the signal transmitting module through the first analog switch group and the third analog switch group, and the ultrasonic sensor B is electrically connected to the signal transmitting module through the second analog switch group and the fourth analog switch group. The ultrasonic sensor A is electrically connected to the signal receiving module through the first analog switch group and the fifth analog switch group, and the ultrasonic sensor B is electrically connected to the signal receiving module through the second analog switch group and the sixth analog switch group.

2. The ultrasonic transceiver signal switching circuit according to claim 1, characterized in that, The control method for the fifth and sixth analog switch groups is XOR control between the direction switch and the receive enable switch.

3. The ultrasonic transceiver signal switching circuit according to claim 2, characterized in that, The control method for the first, second, third, and fourth analog switch groups is directional switch control.

4. The ultrasonic transceiver signal switching circuit according to claim 1, characterized in that, The control method for the fifth and sixth analog switch groups is XOR control between the reverse direction switch and the receive enable switch.

5. The ultrasonic transceiver signal switching circuit according to claim 4, characterized in that, The control method for the first analog switch group and the second analog switch group is XOR control of the direction switch and the receive enable switch.

6. The ultrasonic transceiver signal switching circuit according to claim 5, characterized in that, The control method for the third and fourth analog switch groups is directional switch control.

7. The ultrasonic transceiver signal switching circuit according to claim 1, characterized in that, The signal receiving module includes an amplifier, a comparator, a timing unit, and a processor.

8. The ultrasonic transceiver signal switching circuit according to claim 1, characterized in that, The signal transmission module includes a controller, a pulse generator, and a driver.

9. The ultrasonic transceiver signal switching circuit according to claim 1, characterized in that, The other end of ultrasonic sensor A or ultrasonic sensor B is grounded.

10. The ultrasonic transceiver signal switching circuit according to claim 1, characterized in that, The normally closed terminal of the fourth analog switch group is grounded.

11. The ultrasonic transceiver signal switching circuit according to claim 1, characterized in that, The normally closed terminal of the sixth analog switch group is grounded.

12. The ultrasonic transceiver signal switching circuit according to claim 1, characterized in that, The first, second, third, fourth, fifth, and sixth analog switch groups each include one or two analog switches, wherein the analog switch is one of a single-channel single-pole double-throw analog switch chip, a multi-channel single-pole double-throw analog switch chip, or an integrated chip.

13. The ultrasonic transceiver signal switching circuit according to claim 12, characterized in that, The two signal terminals of the ultrasonic sensor A are electrically connected to the signal transmitting module through the first analog switch group and the third analog switch group, and the two signal terminals of the ultrasonic sensor B are electrically connected to the signal transmitting module through the second analog switch group and the fourth analog switch group. The two signal terminals of the ultrasonic sensor A are electrically connected to the signal receiving module through the first analog switch group and the fifth analog switch group, and the two signal terminals of the ultrasonic sensor B are electrically connected to the signal receiving module through the second analog switch group and the sixth analog switch group.

14. An ultrasonic metering module, characterized in that, Includes an ultrasonic transducer signal transceiver switching circuit as described in any one of claims 1 to 13.

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