CN112781683A

CN112781683A - Liquid level measuring device and liquid level measuring method

Info

Publication number: CN112781683A
Application number: CN201911058122.5A
Authority: CN
Inventors: 王瑞; 王定华; 王璞
Original assignee: XI'AN DINGHUA ELECTRONICS CO LTD
Current assignee: XI'AN DINGHUA ELECTRONICS CO LTD
Priority date: 2019-11-01
Filing date: 2019-11-01
Publication date: 2021-05-11
Anticipated expiration: 2039-11-01
Also published as: CN112781683B

Abstract

The invention provides a liquid level measuring device and a liquid level measuring method, and belongs to the technical field of instruments. The liquid level measuring device includes: changer and a plurality of probe, level measurement device is used for measuring the liquid level of the liquid that the storage tank stored, and the storage tank includes: the liquid inlet pipe and the liquid outlet pipe are communicated with the tank body, the plurality of probes are all used for being installed on the outer bottom surface of the tank body, and the plurality of probes comprise a first probe and a second probe; the distance between the first probe and the liquid inlet pipe is L1, the distance between the first probe and the liquid outlet pipe is L2, the distance between the second probe and the liquid outlet pipe is L3, and the distance between the second probe and the liquid inlet pipe is L4, wherein L1 is less than L2, L1 is less than L4, L3 is less than L4, and L3 is less than L2; the transmitter is used for: and controlling the plurality of probes to transmit measurement signals, and calculating the liquid level value of the liquid according to the condition of the echo signals received by the plurality of probes. The invention solves the problem that the stability of liquid level measurement is influenced by the liquid inlet and outlet of the storage tank. The invention is used for measuring the liquid level.

Description

Liquid level measuring device and liquid level measuring method

Technical Field

The invention relates to the technical field of instruments, in particular to a liquid level measuring device and a liquid level measuring method.

Background

In the chemical production process, a storage tank is used for storing liquid, and a liquid level measuring device is generally used for measuring the liquid level of the liquid in the storage tank.

The liquid level measuring device comprises a transmitter and a probe, the storage tank comprises a tank body, a liquid inlet pipe and a liquid outlet pipe, and the liquid inlet pipe and the liquid outlet pipe are communicated with the tank body. Before the liquid level measuring device is used for measuring the liquid level of the liquid in the storage tank, the probe of the liquid level measuring device needs to be installed on the outer bottom surface of the tank body of the storage tank, so that the probe can emit signals right at the liquid level of the liquid in the tank body.

However, when the liquid inlet pipe feeds liquid or the liquid outlet pipe discharges liquid, liquid near the liquid inlet pipe or the liquid outlet pipe generates vortex, the vortex can absorb and disturb signals sent by the probe, the probe cannot receive effective echo signals, and the stability of liquid level measurement is influenced.

Disclosure of Invention

The application provides a liquid level measurement device and liquid level measurement method, can solve among the correlation technique liquid level measurement device because of the probe can not receive effective echo signal and influenced the problem of liquid level measurement stability when the storage tank passes in and out the liquid, technical scheme is as follows:

in one aspect, a liquid level measuring device is provided, the liquid level measuring device comprising: a transmitter and a plurality of probes, the level measuring device for measuring a level of a liquid stored in a storage tank, the storage tank comprising: the liquid inlet pipe and the liquid outlet pipe are both communicated with the tank body on the outer bottom surface of the tank body, the probes are all used for being mounted on the outer bottom surface of the tank body, and the probes comprise a first probe and a second probe;

on a projection plane parallel to a horizontal plane, the distance between the first probe and the liquid inlet pipe is L1, the distance between the first probe and the liquid outlet pipe is L2, the distance between the second probe and the liquid outlet pipe is L3, the distance between the second probe and the liquid inlet pipe is L4, wherein L1 is less than L2, L1 is less than L4, L3 is less than L4, L3 is less than L2, and the height direction of the tank body is vertical to the horizontal plane;

the transmitter is used for:

controlling the plurality of probes to transmit measurement signals and detecting whether effective echo signals exist in the echo signals received by the plurality of probes;

if an effective echo signal exists in echo signals received by at least two probes in the plurality of probes, taking the average value of the time length from the transmission of the measuring signal to the reception of the effective echo signal of the at least two probes as the measuring time length; if an effective echo signal exists in the echo signal received by only one probe in the plurality of probes, taking the time length from the emission of the measuring signal to the reception of the effective echo signal of the one probe as the measuring time length;

and calculating the liquid level value of the liquid according to the measuring time length and the transmission speed of the measuring signal in the liquid.

Optionally, the plurality of probes further comprises: and on a projection plane parallel to the horizontal plane, the distance between the third probe and the liquid inlet pipe is L5, and the distance between the third probe and the liquid outlet pipe is L6, wherein L1 is less than L5, and L3 is less than L6.

Optionally, in the height direction of the tank body, a central point of a contact surface between the first probe and the tank body, a central point of a contact surface between the second probe and the tank body, and a central point of a contact surface between the third probe and the tank body are located at the same height.

Alternatively, L5 ═ L6.

Optionally, the plurality of probes comprises: a plurality of the first probes, a plurality of the second probes, and a plurality of the third probes.

Optionally, the transmitter is further configured to:

if no effective echo signal exists in the echo signals received by the probes, controlling the probes to simultaneously transmit measurement signals at the same frequency, and overlapping the echo signals received by the probes to obtain an overlapped signal;

and detecting whether effective echo signals exist in the superposed signals, and if the effective echo signals exist in the superposed signals, taking the time length from the simultaneous emission of the measurement signals to the reception of the effective echo signals by the plurality of probes as the measurement time length.

Optionally, the transmitter is further configured to:

if no effective echo signal exists in the echo signals received by the probes, the first probe and the second probe are controlled to simultaneously transmit measurement signals at the same frequency, and then the third probe is controlled to transmit measurement signals, wherein the measurement signals transmitted by the first probe and the measurement signals transmitted by the third probe have the same frequency, andthe phase difference between the measuring signal emitted by the first probe and the measuring signal emitted by the third probe is less than or equal to

The beam range of the measurement signal emitted by the third probe overlaps with the beam ranges of the measurement signals emitted by the first probe and the second probe;

and detecting whether an effective echo signal exists in the echo signals received by the third probe, and if the effective echo signal exists in the echo signals received by the third probe, taking the time length from the emission of the measurement signal to the reception of the effective echo signal by the third probe as the measurement time length.

In another aspect, a liquid level measuring method is provided for a transmitter in the above liquid level measuring apparatus, the liquid level measuring apparatus including: a transmitter and a plurality of probes, the level measuring device for measuring a level of a liquid stored in a storage tank, the storage tank comprising: the liquid inlet pipe and the liquid outlet pipe are both communicated with the tank body on the outer bottom surface of the tank body, the probes are all used for being mounted on the outer bottom surface of the tank body, and the probes comprise a first probe and a second probe;

on a projection plane parallel to a horizontal plane, the distance between the first probe and the liquid inlet pipe is L1, the distance between the first probe and the liquid outlet pipe is L2, the distance between the second probe and the liquid outlet pipe is L3, the distance between the second probe and the liquid inlet pipe is L4, wherein L1 is less than L2, L1 is less than L4, L3 is less than L4, L3 is less than L2, and the height direction of the tank body is vertical to the horizontal plane; the method comprises the following steps:

Optionally, the method further comprises:

Optionally, the plurality of probes further comprises: a third probe, on the projection plane parallel to the horizontal plane, the distance between the third probe and the liquid inlet pipe is L5, the distance between the third probe and the liquid outlet pipe is L6, wherein L1 is less than L5, and L3 is less than L6, and the method further comprises:

if no effective echo signal exists in the echo signals received by the probes, the first probe and the second probe are controlled to simultaneously transmit measurement signals at the same frequency, then the third probe is controlled to transmit measurement signals, the measurement signals transmitted by the first probe and the measurement signals transmitted by the third probe are controlled to be at the same frequency, and the phase difference between the measurement signals transmitted by the first probe and the measurement signals transmitted by the third probe is smaller than or equal to

The beneficial effect that technical scheme that this application provided brought is: when the liquid inlet pipe is used for feeding liquid, the second probe is far away from the liquid inlet pipe compared with the first probe, so that the second probe is less influenced by the liquid feeding compared with the first probe, and when the second probe can receive an effective echo signal, the transmitter can take the time length from the transmission of the measurement signal to the reception of the effective echo signal by the second probe as the measurement time length so as to be convenient for the transmitter to calculate the liquid level value; when the liquid outlet pipe discharges liquid, because the first probe is far away from the liquid outlet pipe compared with the second probe, the first probe is less influenced by the liquid outlet compared with the second probe, and when the first probe can receive the effective echo signal, the transmitter can use the time length from the transmission of the measurement signal to the reception of the effective echo signal as the measurement time length so as to be convenient for the transmitter to calculate the liquid level value. The liquid level measuring device is less influenced by liquid inlet or liquid outlet, and the measuring stability of the liquid level measuring device is improved.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the application.

Drawings

In order to illustrate the embodiments of the present invention more clearly, the drawings that are needed in the description of the embodiments will be briefly described below, it being apparent that the drawings in the following description are only some embodiments of the invention, and that other drawings may be derived from those drawings by a person skilled in the art without inventive effort.

FIG. 1 is a schematic view of a prior art liquid level measuring device mounted on a storage tank;

FIG. 2 is a schematic view of a liquid level measuring device installed on a storage tank according to an embodiment of the present invention;

fig. 3 is a schematic diagram of effective echo signals in echo signals according to an embodiment of the present invention;

FIG. 4 is a schematic view of another liquid level measuring device mounted on a storage tank according to an embodiment of the present invention;

FIG. 5 is a schematic view of another liquid level measuring device installed on a storage tank according to an embodiment of the present invention;

fig. 6 is a schematic waveform diagram of a superimposed signal and an echo signal received by a probe according to an embodiment of the present invention;

fig. 7 is a schematic waveform diagram of another superimposed signal and an echo signal received by a probe according to an embodiment of the present invention;

fig. 8 is a schematic waveform diagram of measurement signals emitted by the first probe, the second probe and the third probe according to the embodiment of the present invention;

FIG. 9 is a schematic diagram of new beam ranges for measurements transmitted by the first probe, the second probe, and the third probe according to the embodiment of the present invention;

FIG. 10 is a flow chart of a method for measuring a liquid level according to an embodiment of the present invention;

FIG. 11 is a flow chart of another method for measuring fluid level provided by an embodiment of the present invention;

fig. 12 is a flowchart of another liquid level measuring method according to an embodiment of the present invention.

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and together with the description, serve to explain the principles of the application.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention clearer, the present invention will be described in further detail with reference to the accompanying drawings, and it is apparent that the described embodiments are only a part of the embodiments of the present invention, not all of the embodiments. 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.

Fig. 1 is a schematic view of a prior art liquid level measuring device mounted on a storage tank, and the left side of fig. 1 shows a front view of the storage tank and an outside liquid level device, and the right side of fig. 1 shows a bottom view of the storage tank and a probe. As shown in figure 1, the liquid level measuring device comprises a transmitter and a probe which are connected, the storage tank comprises a tank body, a manhole flange, a liquid inlet pipe and a liquid outlet pipe, the manhole flange, the liquid inlet pipe and the liquid outlet pipe are all communicated with the tank body, and the probe is arranged on the outer bottom surface of the tank body.

When the liquid level measuring device is used for measuring the liquid level of liquid (not shown in figure 1) stored in the tank body, the transmitter controls the probe to transmit a measuring signal, the measuring signal is reflected by the liquid level to be an echo signal when reaching the liquid level of the liquid, and after the probe receives the echo signal, the transmitter can detect whether an effective echo signal (the effective echo signal is an echo signal with a signal energy value or an amplitude value reaching a certain set value) exists in the echo signal received by the probe. When the transmitter detects an effective echo signal from an echo signal received by the probe, the time from the transmission of a measurement signal to the reception of the effective echo signal by the probe is taken as the measurement time, and then the total path of the measurement signal from the probe to the liquid level and the total path of the echo signal from the liquid level to the probe can be measured by multiplying the measurement time by the propagation speed of the signal in the liquid, wherein one half of the total path is the liquid level height of the liquid level.

However, in the process of measuring the liquid level of the liquid level measuring device, if the liquid inlet pipe enters the liquid or the liquid outlet pipe exits the liquid, and the distance from the probe to the liquid inlet pipe or the distance from the probe to the liquid outlet pipe is short, the vortex generated by the liquid near the liquid inlet pipe or the liquid near the liquid outlet pipe can absorb the measuring signal sent by the probe and the echo signal reflected by the liquid level, so that the probe cannot receive the effective echo signal, and the measuring stability of the liquid level measuring device is influenced.

Fig. 2 is a schematic diagram of a liquid level measuring device provided by an embodiment of the invention and installed on a storage tank, wherein the left side of fig. 2 shows a front view of the storage tank and an external liquid level device, and the right side of fig. 2 shows a bottom view of the storage tank and a probe.

As shown in fig. 2, the liquid level measuring apparatus includes: a transmitter 20 and a plurality of probes, a level measuring device for measuring a level of a liquid stored in a tank 00, the tank 00 comprising: jar body 01, feed liquor pipe 02 and drain pipe 04 all communicate with jar body 01, and a plurality of probes all are used for installing the outer bottom surface at jar body 01, and a plurality of probes include first probe 11 and second probe 12. On a projection plane (not shown in fig. 2) parallel to the horizontal plane, the distance between the first probe 11 and the liquid inlet pipe 02 is L1, the distance between the first probe 11 and the liquid outlet pipe 04 is L2, the distance between the second probe 12 and the liquid outlet pipe 04 is L3, and the distance between the second probe 12 and the liquid inlet pipe 02 is L4, wherein L1 is less than L2, L1 is less than L4, L3 is less than L4, L3 is less than L2, and the height direction P1 of the tank body 01 is vertical to the horizontal plane.

Note that "the distance between the first probe 11 and the liquid inlet pipe 02 on the projection plane parallel to the horizontal plane is L1" means that the distance between the projection of the first probe 11 on the projection plane and the projection of the liquid inlet pipe 02 on the projection plane is L1.

Transmitter 20 is used to: controlling the plurality of probes to transmit measurement signals and detecting whether effective echo signals exist in the echo signals received by the plurality of probes; if the echo signals received by at least two probes in the plurality of probes have effective echo signals, taking the average value of the time length from the transmission of the measuring signals to the reception of the effective echo signals of the at least two probes as the measuring time length; if only one probe in the plurality of probes receives an effective echo signal, the time length from the transmission of the measuring signal to the reception of the effective echo signal of the probe is taken as the measuring time length.

For example, after the transmitter 20 controls the plurality of probes to transmit the measurement signals, if a valid echo signal exists in the echo signals received by the first probe 11 and the second probe 12, the time period from the transmission of the measurement signal to the reception of the valid echo signal by the first probe 11 is T1, and the time period from the transmission of the measurement signal to the reception of the valid echo signal by the second probe 12 is T2, the method will be implemented by the following steps

To measure the duration. Alternatively, after the transmitter 20 controls all of the plurality of probes to transmit the measurement signals, if only the echo signal received by the first probe 11 has a valid echo signal, the time period T1 from the transmission of the measurement signal to the reception of the valid echo signal by the first probe 11 is taken as the measurement time period, and if only the echo signal received by the second probe 12 has a valid echo signal, the time period from the transmission of the measurement signal to the reception of the valid echo signal by the second probe 12 is taken as the measurement time periodThe measurement period is taken as a period T2.

After acquiring the measurement duration, transmitter 20 is also used to: and calculating the liquid level value of the liquid according to the measuring time length and the transmission speed of the measuring signal in the liquid.

By way of example, the level value of the liquid may be calculated according to the following formula:

wherein V is the transmission speed of the measurement signal in the liquid, T is the measurement duration acquired by the transmitter 20, and L is the liquid level value of the liquid. The V multiplied by T can calculate the total path of the measuring signal from the probe to the liquid level and the echo signal from the liquid level to the probe, and half of the total path is the liquid level value of the liquid.

It should be noted that, in the process of controlling the multiple probes to all transmit the measurement signal, the transmitter 20 may control the multiple probes to transmit the measurement signal simultaneously, or may control the multiple probes to transmit the measurement signal in a time-sharing manner, which is not limited in the embodiment of the present invention.

In summary, in the liquid level measuring device provided in the embodiment of the invention, the plurality of probes are installed on the outer bottom surface of the tank body of the storage tank, and among the plurality of probes, a distance between the first probe and the liquid inlet pipe is smaller than a distance between the first probe and the liquid outlet pipe, and is smaller than a distance between the second probe and the liquid inlet pipe, and a distance between the second probe and the liquid outlet pipe is smaller than a distance between the second probe and the liquid inlet pipe, and is smaller than a distance between the first probe and the liquid outlet pipe. That is, the first probe is closer to the liquid inlet pipe and farther from the liquid outlet pipe than the second probe, and the second probe is closer to the liquid outlet pipe and farther from the liquid inlet pipe than the first probe.

Therefore, when the liquid inlet pipe is used for feeding liquid, the second probe is far away from the liquid inlet pipe compared with the first probe, so that the second probe is less influenced by the liquid inlet compared with the first probe, and when the second probe can receive the effective echo signal, the transmitter can take the time from the transmission of the measurement signal to the reception of the effective echo signal by the second probe as the measurement time so as to be convenient for the transmitter to calculate the liquid level value; when the liquid outlet pipe discharges liquid, because the first probe is far away from the liquid outlet pipe compared with the second probe, the first probe is less influenced by the liquid outlet compared with the second probe, and when the first probe can receive the effective echo signal, the transmitter can use the time length from the transmission of the measurement signal to the reception of the effective echo signal as the measurement time length so as to be convenient for the transmitter to calculate the liquid level value. The liquid level measuring device is less influenced by liquid inlet or liquid outlet, and the measuring stability of the liquid level measuring device is improved.

Optionally, the storage tank 00 may further include a manhole flange 03, and the manhole flange 03 is installed on the outer bottom surface of the tank body 01. It should be noted that the manhole flange is a component of a manhole, and the manhole refers to an open structure for people to enter and exit equipment (such as the tank body 01 in the embodiment of the present invention) for installation, maintenance and safety inspection.

It should be noted that, in the embodiment of the present invention, the effective echo signal refers to a signal whose signal amplitude or energy value reaches a certain set value in the echo signal received by the probe.

For example, fig. 3 shows a schematic diagram of effective echo signals in echo signals, as shown in the left side of fig. 3, an effective echo signal X11 with an amplitude greater than a set value F1 exists in the echo signal X1, and as shown in the right side of fig. 3, an effective echo signal X21 with an energy value greater than a set value N1 exists in the echo signal X2.

Fig. 4 is a schematic view of another liquid level measuring device provided by the embodiment of the invention and installed on a storage tank, wherein the left side of fig. 4 shows a front view of the storage tank and an external liquid level device, and the right side of fig. 4 shows a bottom view of the storage tank and a probe.

Referring to fig. 2 and fig. 4, on the basis of fig. 2, the plurality of probes may further include: and in the direction parallel to the horizontal plane, the distance between the third probe 13 and the liquid inlet pipe 02 is L5, and the distance between the third probe 13 and the liquid outlet pipe 04 is L6, wherein L1 is less than L5, and L3 is less than L6.

When the liquid inlet pipe 02 feeds liquid and the liquid outlet pipe 04 discharges liquid, the third probe 13 is far away from the liquid inlet pipe 02 compared with the first probe 11, and the third probe 13 is far away from the liquid outlet pipe 03 compared with the second probe 12, so that the third probe 13 is less influenced by the liquid inlet and the liquid discharge. When the third probe 13 receives a valid echo signal, the transmitter can use the time taken by the third probe from the transmission of the measurement signal to the reception of the valid echo signal as the measurement time so that the transmitter can calculate the level value. The liquid level measuring device is less influenced by the simultaneous liquid inlet and outlet, and the measuring stability of the liquid level measurement is further improved.

The following describes different ways of the transmitter 20 obtaining the measurement duration according to the signal transmission and reception of the first probe 11, the second probe 12 and the third probe 13:

after the transmitter 20 controls the plurality of probes to transmit the measurement signals, if there is a valid echo signal in the echo signals received by the first probe 11, the second probe 12 and the third probe 13, the average value of the time length T1 from the transmission of the measurement signal by the first probe 11 to the reception of the valid echo signal, the time length T2 from the transmission of the valid echo signal by the second probe 12 and the time length T3 from the transmission of the measurement signal by the third probe 13 to the reception of the valid echo signal (i.e. the average value of the time length T3 from the transmission of the measurement signal by the third probe 13 to the reception

) To measure the duration.

After the transmitter 20 controls the multiple probes to transmit the measurement signals, if only the echo signal received by the first probe 11 has a valid echo signal, T1 is used as the measurement duration, if only the echo signal received by the second probe 12 has a valid echo signal, T2 is used as the measurement duration, and if only the echo signal received by the third probe 13 has a valid echo signal, T3 is used as the measurement duration.

After the transmitter 20 controls the plurality of probes to transmit the measurement signals, if only the effective echo signals exist in the echo signals received by the first probe 11 and the third probe 12, the effective echo signals are received by the transmitter

For measuring the time length, if only the effective echo signals exist in the echo signals received by the first probe 11 and the third probe 13, the effective echo signals are received

For measuring the length of time, if only the second probe 12 and the third probe are usedThe echo signals received by the head 13 contain valid echo signals, and then

To measure the duration.

Alternatively, the transmitter 20 may be an ultrasonic level transmitter, the first probe 11, the second probe 12 and the third probe 13 may be ultrasonic probes, and the transmitter 20 is used for controlling the first probe 11, the second probe 12 and the third probe 13 to transmit and receive ultrasonic signals. It should be noted that the first probe 11, the second probe 12 and the third probe 13 may have the same resonance frequency point, and the transmitter 20 may be configured to control the first probe 11, the second probe 12 and the third probe 13 to transmit and receive the ultrasonic signals with the same frequency; the resonant frequency points of the first probe 11, the second probe 12 and the third probe 13 can also be different, and the transmitter can be used to control the first probe 11, the second probe 12 and the third probe 13 to transmit and receive ultrasonic signals of different frequencies.

With continued reference to fig. 2 and 4, in the height direction P1 of the tank 01, the contact surface center point (not shown in fig. 2 and 4) of the first probe 11 and the tank 01, the contact surface center point (not shown in fig. 2 and 4) of the second probe 12 and the tank 01, and the contact surface center point (not shown in fig. 2 and 4) of the third probe 13 and the tank 01 are located at the same height.

Under such a structure, the distances between the signal transmitting surface of the first probe 11, the signal transmitting surface of the second probe 12 and the signal transmitting surface of the third probe 13 and the liquid level of the liquid in the tank 01 are the same, so that the time difference from the transmission of the signals to the reception of the signals of the first probe 11, the second probe 12 and the third probe 13 is small, the measurement error of the time length from the transmission of the measurement signals by at least two probes to the reception of the effective echo signals by the transmitter 20 is reduced, and the measurement accuracy of the transmitter is improved.

The height direction P1 of the can body 01 is perpendicular to the surface of the liquid surface in the can body, that is, the height direction P1 is parallel to the direction of gravity.

Alternatively, L5 ═ L6. Also the third probe 13 is the same with feed liquor pipe 02 distance and with drain pipe 04 distance, so set up under the mode, when feed liquor pipe 02 feed liquor and drain pipe 04 were gone out simultaneously, feed liquor and play liquid were comparatively balanced to third probe 13 influence, and third probe 13 is difficult because of feed liquor range is too big or play liquid range is too big and lead to it not to receive effective echo signal, has further improved the measurement accuracy of changer.

Fig. 5 is a schematic view of a liquid level measuring device installed on a storage tank according to another embodiment of the present invention, wherein the left side of fig. 5 shows a front view of the storage tank and the liquid level measuring device, and the right side of fig. 5 shows a bottom view of the storage tank and a probe.

Referring to fig. 2, 4 and 5, the plurality of probes may include: a plurality of first probes 11, a plurality of second probes 12 and a plurality of third probes 13. Also, the total number of the probes is large, and under the structure, after the transmitter 20 controls the plurality of probes to transmit the measurement signals, the probability that the probes capable of receiving effective echo signals exist in the plurality of probes is high, so that the measurement stability of the transmitter is improved.

Optionally, the plurality of first probes 11, the plurality of second probes 12, and the plurality of third probes 13 are distributed on two sides of the direction from the liquid outlet pipe 02 to the liquid outlet pipe 04. So under the mode of setting for a plurality of probes distribute comparatively evenly around feed liquor pipe 02 and drain pipe 04, after changer 20 control a plurality of probes all transmit measuring signal, the probability that has the probe that can receive effective echo signal in a plurality of probes further increases, has further improved the measurement stability of changer.

It should be noted that, in fig. 5, only the multiple probes include two first probes 11, two second probes 12, and two third probes 13 as an example, alternatively, the multiple probes may further include other numbers (e.g., three) of the first probes 11, the second probes 12, and the third probes, which is not limited in this embodiment of the present invention.

Continuing with fig. 2, 4 and 5, optionally, the transmitter 20 in the liquid level measuring device can also be used for: the method comprises the steps that effective echo signals do not exist in echo signals received by a plurality of probes, the probes are controlled to simultaneously transmit measurement signals at the same frequency, and the echo signals received by the probes are superposed to obtain superposed signals; the transmitter 20 can then detect whether there is a valid echo signal in the superimposed signal, and if there is a valid echo signal in the superimposed signal, the length of time taken by the multiple probes from the time the measurement signals are simultaneously transmitted to the time the valid echo signals are received is used as the measurement length of time.

In this way, by superposing the echo signals received by the plurality of probes, the amplitude of the superposed signal is greater than the amplitude of the echo signal received by each probe, so as to improve the probability that the transmitter 20 detects a valid echo signal from the superposed signal, and improve the measurement stability of the liquid level measurement device.

It should be noted that, the controlling of the multiple probes by the transmitter 20 to simultaneously transmit the measurement signal at the same frequency means: the transducer 20 controls the plurality of probes to emit measurement signals of the same frequency (e.g., ultrasonic signals of the same frequency) at the same time.

It should be noted that, in fig. 2, fig. 4 and fig. 5, only the storage tank 00 is taken as an example, alternatively, the storage tank in the embodiment of the present invention may also be a storage tank with another shape (such as a standing tank or a sausage tank), and the embodiment of the present invention is not limited thereto. In addition, in fig. 2, fig. 4 and fig. 5, only the liquid inlet pipe 02 and the liquid outlet pipe 04 in the storage tank 00 are taken as an example to communicate with the tank 01 at the outer bottom surface of the tank 01, alternatively, in the storage tank 00, the liquid inlet pipe 02 and the liquid outlet pipe 04 may also communicate with the tank 01 at other positions of the tank 01 (for example, the liquid inlet pipe 02 and the liquid outlet pipe 04 communicate with the tank 01 at the outer top surface of the tank 01), which is not limited in this embodiment of the present invention. In fig. 2, 4 and 5, only one manhole flange 03 is included in the storage tank 00, and the manhole flange 03 is in communication with the tank body at the outer bottom surface of the tank body 01 as an example, alternatively, the storage tank 00 may further include another number (e.g., two) of manhole flanges 03, and the manhole flanges 03 may also be in communication with the tank body 01 at another position of the tank body 01 (e.g., the outer top surface or the side surface of the tank body 01), which is not limited in this embodiment of the present invention. Note that the liquid level measuring devices in fig. 2, 4, and 5 are external liquid level measuring devices, and the first probe 11, the second probe 12, and the third probe 13 are external probes.

The following describes a process of the transmitter 20 for superimposing echo signals received by a plurality of probes, by taking the liquid level measuring apparatus in fig. 4 as an example:

fig. 6 is a schematic waveform diagram of a superimposed signal and an echo signal received by a probe according to an embodiment of the present invention, please refer to fig. 4 and fig. 6, after the transmitter 20 controls the first probe 11, the second probe 12, and the third probe 13 to simultaneously transmit measurement signals at the same frequency, if the phases of the echo signals received by the first probe 11, the second probe 12, and the third probe 13 are the same, the transmitter 20 may superimpose the echo signal B1 received by the first probe 11, the echo signal B2 received by the second probe, and the echo signal received by the third probe 13 to obtain a superimposed signal B4.

Fig. 7 is a schematic diagram of waveforms of another superimposed signal and an echo signal received by a probe according to an embodiment of the present invention, please refer to fig. 4 and 7, after the transmitter 20 controls the first probe 11, the second probe 12, and the third probe 13 to simultaneously transmit measurement signals at the same frequency; if the first probe 11, the second probe 12, and the third probe 13 receive echo signals at different times, the transmitter 20 may shift the phase of the echo signal B1 received by the first probe 11 and the phase of the echo signal B2 received by the second probe 12 to obtain a phase-shifted echo signal B11 and a phase-shifted echo signal B21, so that the phase-shifted echo signal B11 and the phase-shifted echo signal B21 are both in phase with the echo signal B3. Then, the phase-shifted echo signal B11, the phase-shifted echo signal B21, and the echo signal B3 are added to obtain a added signal B5.

It should be noted that, in practical application, after the echo signals are received by the multiple probes, the transmitter may amplify the echo signals received by the multiple probes, and then superimpose the echo signals received by the multiple probes or superimpose the echo signals after shifting the phase, so as to detect effective echo signals from the superimposed signals.

Referring to fig. 4 and 5, optionally, after the transmitter 20 controls the plurality of probes to all transmit the measurement signals and detects whether a valid echo signal exists in the echo signals received by the plurality of probes, the transmitter 20 may further be configured to: if no effective echo signal exists in the echo signals received by the probes, the first probe 11 and the second probe 12 are controlled to simultaneously transmit measurement signals at the same frequency, and then the third probe 13 is controlled to transmit the measurement signals.

It should be noted that the measurement signal emitted by the first probe 11 and the measurement signal emitted by the third probe 13 have the same frequency, and the phase difference between the measurement signal emitted by the first probe and the measurement signal emitted by the third probe 13 is less than or equal to

And the beam range of the measurement signal emitted by the third probe 13 overlaps with the beam ranges of the measurement signals emitted by the first probe 11 and the second probe 12.

Next, the transmitter 20 may detect whether a valid echo signal exists in the echo signal received by the third probe 13, and if a valid echo signal exists in the echo signal received by the third probe 13, the time length from the time when the third probe 13 transmits the measurement signal to the time when the valid echo signal is received is used as the measurement time length.

In this way, the measurement signals transmitted by the third probe 13 after the measurement signals transmitted by the first probe 11 and the second probe 12 after the measurement signals are bundled, so that the measurement signals transmitted by the first probe 11 and the second probe 12 are concentrated in the direction of the measurement signals transmitted by the third probe 13, the signal intensity in the direction from the third probe 13 to the liquid level is increased, the intensity of the echo signal received by the third probe 13 is increased, the transmitter 20 is favorable for detecting the effective echo signal from the echo signal received by the third probe 13, and the measurement stability of the liquid level measurement device is improved.

Taking the liquid level measuring device in fig. 4 as an example, a process of the transmitter 20 firstly controlling the first probe 11 and the second probe 12 to simultaneously transmit the measurement signal at the same frequency, and then controlling the third probe 13 to transmit the measurement signal will be described below:

fig. 8 is a schematic waveform diagram of measurement signals emitted by the first probe, the second probe, and the third probe according to the embodiment of the present invention, and fig. 9 is a schematic diagram of a new beam range for measurement emitted by the first probe, the second probe, and the third probe according to the embodiment of the present invention.

Referring to fig. 4, 8 and 9, after the transmitter 20 controls the first probe 11 and the second probe 12 to simultaneously emit the measurement signals at the same frequency, the phase of the measurement signal C1 emitted by the first probe 11 is the same as the phase of the measurement signal C2 emitted by the second probe 12; the transmitter 20 then controls the third probe 13 to emit a measurement signal C3. Since the measurement signal C3 emitted in the following is at the same frequency as the measurement signal C1 and the measurement signal C2 emitted in the preceding, the phase difference between the measurement signal C3 emitted in the following and the measurement signal C1 and the measurement signal C2 emitted in the preceding is smaller than

And the beam range F3 of the measurement signal emitted by the third probe 13 overlaps with both the beam range S1 of the measurement signal emitted by the first probe 11 and the beam range S2 of the measurement signal emitted by the second probe 12; thus, the subsequently transmitted measurement signal C3 will bundle the previously transmitted measurement signal C1 and measurement signal C2 to generate a superimposed signal C4 which coincides with the propagation direction of the measurement signal C3.

It should be noted that fig. 9 only illustrates that the beam range S3 of the measurement signal C3 overlaps with the beam range S1 of the measurement signal C1 and the beam range S2 of the first measurement signal C2. Optionally, when the transmitter acquires the measurement duration in other manners in the embodiment of the present invention (for example, the transmitter controls a plurality of probes to transmit measurement signals simultaneously, and then acquires the measurement duration according to the received echo conditions of the plurality of probes), a beam range of the measurement signal transmitted by the third probe does not overlap with beam ranges of the measurement signals transmitted by the first probe and the second probe, which is not limited in the embodiment of the present invention.

In fig. 9, only the spherical wave signals are taken as an example of the measurement signals emitted by the respective probes. Optionally, the measurement signal emitted by each probe in the embodiment of the present invention may also be another type of signal (such as cylindrical wave or plane wave), which is not limited in the embodiment of the present invention.

In summary, in the liquid level measuring device provided in the embodiment of the present invention, when the liquid inlet pipe enters the liquid, because the second probe is farther away from the liquid inlet pipe than the first probe, the second probe is less affected by the liquid inlet than the first probe, and when the second probe can receive the effective echo signal, the transmitter can use the time length from the time when the second probe transmits the measurement signal to the time when the second probe receives the effective echo signal as the measurement time length, so that the transmitter can calculate the level value; when the liquid outlet pipe discharges liquid, because the first probe is far away from the liquid outlet pipe compared with the second probe, the first probe is less influenced by the liquid outlet compared with the second probe, and when the first probe can receive the effective echo signal, the transmitter can use the time length from the transmission of the measurement signal to the reception of the effective echo signal as the measurement time length so as to be convenient for the transmitter to calculate the liquid level value. The liquid level measuring device is less influenced by liquid inlet or liquid outlet, and the measuring stability of the liquid level measuring device is improved.

Fig. 10 is a flowchart of a liquid level measuring method according to an embodiment of the present invention, where the liquid level measuring method can be used in a transmitter of any one of the above liquid level measuring devices, and the liquid level measuring method can include:

and step 1001, controlling the plurality of probes to transmit measurement signals.

Step 1002, detecting whether effective echo signals exist in the echo signals received by the plurality of probes.

If a valid echo signal exists in the echo signals received by the plurality of probes, executing step 1003; if there is no valid echo signal among the echo signals received by the plurality of probes, step 1001 is executed.

Step 1003, if effective echo signals exist in the echo signals received by at least two probes in the plurality of probes, taking the average value of the time length from the time when the at least two probes transmit the measuring signals to the time when the effective echo signals are received as the measuring time length; if only one of the probes receives an effective echo signal, the time length from the transmission of the measuring signal to the reception of the effective echo signal of one probe is taken as the measuring time length.

And step 1004, calculating the liquid level value of the liquid according to the measuring time length and the transmission speed of the measuring signal in the liquid.

In summary, in the liquid level measuring method provided by the embodiment of the invention, the time period from the transmission of the measurement signal by the second probe, which is less affected by the liquid inlet, to the reception of the effective echo signal can be used as the measurement time period, and the time period from the transmission of the measurement signal by the first probe, which is less affected by the liquid outlet, to the reception of the effective echo signal can be used as the measurement time period, so that the liquid level value can be calculated according to the measurement time period and the transmission speed of the measurement signal in the liquid during the liquid inlet or liquid outlet, the liquid inlet or liquid outlet is less affected during the liquid level measuring process, and the stability of the liquid level measuring process is improved.

Fig. 11 is a flow chart of another liquid level measuring method provided by the embodiment of the invention, which can be used in a transmitter of any one of the liquid level measuring devices, and the liquid level measuring method can include:

and step 1101, controlling a plurality of probes to transmit measurement signals.

Step 1102, detecting whether effective echo signals exist in the echo signals received by the plurality of probes.

If there is a valid echo signal in the echo signals received by the probes, executing step 1103; if there is no valid echo signal among the echo signals received by the plurality of probes, step 1105 is performed.

1103, if effective echo signals exist in echo signals received by at least two probes in the plurality of probes, taking the average value of the time length from the time when the at least two probes transmit the measuring signals to the time when the effective echo signals are received as the measuring time length; if only one of the probes receives an effective echo signal, the time length from the transmission of the measuring signal to the reception of the effective echo signal of one probe is taken as the measuring time length.

And 1104, calculating the liquid level value of the liquid according to the measuring time length and the transmission speed of the measuring signal in the liquid.

And step 1105, controlling a plurality of probes to simultaneously transmit measurement signals at the same frequency.

And step 1106, overlapping the echo signals received by the probes to obtain an overlapped signal.

Step 1107, detect whether there is a valid echo signal in the superimposed signal.

If a valid echo signal exists in the superimposed signal, go to step 1108; if a valid echo signal exists in the superimposed signal, step 1101 is executed.

Step 1108, the time length from the simultaneous emission of the measurement signals to the reception of the effective echo signals of the plurality of probes is taken as the measurement time length.

And step 1109, calculating the liquid level value of the liquid according to the measuring time length and the transmission speed of the measuring signal in the liquid.

Therefore, the echo signals received by the probes are superposed, so that the amplitude of the superposed signal is greater than that of the echo signals received by each probe, the probability of detecting effective echo signals from the superposed signal is improved, and the stability of the liquid level measurement process is improved.

Fig. 12 is a flow chart of another liquid level measuring method provided by the embodiment of the invention, which can be used for a transmitter in the liquid level measuring device in fig. 4 or fig. 5, and the liquid level measuring method can include:

step 1201, controlling a plurality of probes to transmit measurement signals.

And step 1202, detecting whether effective echo signals exist in the echo signals received by the plurality of probes.

If there is a valid echo signal in the echo signals received by the probes, executing step 1203; if no valid echo signal exists in the echo signals received by the plurality of probes, step 1205 is executed.

Step 1203, if effective echo signals exist in echo signals received by at least two probes in the plurality of probes, taking an average value of time lengths from the time when the at least two probes transmit the measuring signals to the time when the effective echo signals are received as measuring time length; if only one of the probes receives an effective echo signal, the time length from the transmission of the measuring signal to the reception of the effective echo signal of one probe is taken as the measuring time length.

And 1204, calculating the liquid level value of the liquid according to the measuring time length and the transmission speed of the measuring signal in the liquid.

Step 1205, the first probe and the second probe are controlled to simultaneously transmit the measurement signal at the same frequency, and then the third probe is controlled to transmit the measurement signal.

It should be noted that, in step 1205, the measurement signal transmitted by the first probe and the measurement signal transmitted by the third probe have the same frequency, and the phase difference between the measurement signal transmitted by the first probe and the measurement signal transmitted by the third probe is less than or equal to

The beam range of the measurement signal transmitted by the third probe overlaps with the beam ranges of the measurement signals transmitted by the first probe and the second probe.

And step 1206, detecting whether an effective echo signal exists in the echo signals received by the third probe.

If a valid echo signal exists in the echo signals received by the third probe, executing step 1207; if there is no valid echo signal in the echo signals received by the third probe, step 1201 is executed.

Step 1207, the time length from the transmission of the measuring signal to the reception of the effective echo signal of the third probe is taken as the measuring time length.

And 1208, calculating the liquid level value of the liquid according to the measuring time length and the transmission speed of the measuring signal in the liquid.

Therefore, the measuring signal transmitted by the third probe can be bundled to the measuring signal transmitted by the first probe and the second probe, so that the measuring signal transmitted by the first probe and the second probe is concentrated to the direction of the measuring signal transmitted by the third probe, the signal intensity in the direction from the third probe to the liquid level of the liquid is improved, the intensity of the echo signal received by the third probe is higher, the effective echo signal can be detected from the echo signal received by the third probe, and the stability of the liquid level measuring process is improved.

In any of the above liquid level measuring methods, after the measurement duration is obtained, the measurement duration may be multiplied by the propagation speed of the measurement signal in the liquid to obtain the total path taken by the measurement signal from the probe to the liquid level and the echo signal from the liquid level to the receiving probe, and then half of the total path is determined as the level value of the liquid in the tank.

It should be noted that, the apparatus embodiment provided in the embodiment of the present invention can be mutually referred to with a corresponding method embodiment, and the embodiment of the present invention does not limit this. The sequence of the steps of the method embodiments provided by the embodiments of the present invention can be appropriately adjusted, and the steps can be correspondingly increased or decreased according to the situation, and any method that can be easily conceived by those skilled in the art within the technical scope disclosed by the present invention shall be covered by the protection scope of the present invention, and therefore, the detailed description thereof shall not be repeated.

Other embodiments of the invention will be apparent to those skilled in the art from consideration of the specification and practice of the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of the invention following, in general, the principles of the invention and including such departures from the present disclosure as come within known or customary practice within the art to which the invention pertains. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the invention being indicated by the following claims.

It will be understood that the invention is not limited to the precise arrangements described above and shown in the drawings and that various modifications and changes may be made without departing from the scope thereof. The scope of the invention is limited only by the appended claims.

Claims

1. A liquid level measuring device, characterized in that the liquid level measuring device comprises: a transmitter and a plurality of probes, the level measuring device for measuring a level of a liquid stored in a storage tank, the storage tank comprising: the liquid inlet pipe and the liquid outlet pipe are communicated with the tank body, the probes are all used for being mounted on the outer bottom surface of the tank body, and the probes comprise a first probe and a second probe;

the transmitter is used for:

2. The fluid level measurement device of claim 1, wherein the plurality of probes further comprises: and on the projection plane parallel to the horizontal plane, the distance between the third probe and the liquid inlet pipe is L5, and the distance between the third probe and the liquid outlet pipe is L6, wherein L1 is less than L5, and L3 is less than L6.

3. The liquid level measuring device of claim 2, wherein the contact surface center point of the first probe and the tank, the contact surface center point of the second probe and the tank, and the contact surface center point of the third probe and the tank are located at the same height in the height direction of the tank.

4. A liquid level measuring device according to claim 2, characterized in that L5-L6.

5. A liquid level measuring device as claimed in any one of claims 2 to 4, wherein said plurality of probes comprises: a plurality of the first probes, a plurality of the second probes, and a plurality of the third probes.

6. The fluid level measuring device of any one of claims 1 to 4, wherein the transmitter is further configured to:

7. The fluid level measuring device of any one of claims 2 to 4, wherein the transmitter is further configured to:

8. A liquid level measuring method, characterized by being used in a transmitter of the liquid level measuring apparatus of any one of claims 1 to 7, the liquid level measuring apparatus comprising: a transmitter and a plurality of probes, the level measuring device for measuring a level of a liquid stored in a storage tank, the storage tank comprising: the liquid inlet pipe and the liquid outlet pipe are communicated with the tank body, the probes are all used for being mounted on the outer bottom surface of the tank body, and the probes comprise a first probe and a second probe;

9. The method of claim 8, further comprising:

10. The method of claim 8, wherein the plurality of probes further comprises: a third probe, on the projection plane parallel to the horizontal plane, the distance between the third probe and the liquid inlet pipe is L5, the distance between the third probe and the liquid outlet pipe is L6, wherein L1 is less than L5, and L3 is less than L6, and the method further comprises: