1. A variable range level gauge comprising:

the elastic diaphragm is arranged in the base and used for converting the external pressure into the elastic deformation of the diaphragm;

the diaphragm area regulator is arranged at the upper end of the elastic diaphragm and is used for realizing range adjustment by changing the effective area of the diaphragm;

the fiber Bragg grating is arranged in the middle of the circular elastic body and used for reflecting the pressure bearing size through the changed grating spacing size after stress and further converting the pressure bearing size into liquid level variation;

the lower end of the circular elastic body penetrates through the membrane area regulator and then is elastically connected with the elastic membrane, and the circular elastic body is used for transmitting the deformation of the elastic membrane to the fiber Bragg grating so as to change the distance between the gratings and further convert the change into the variation of the wavelength;

and the wire passing column is a wire passing hole of the fiber Bragg grating and is used for enabling a communication wire connected with the fiber Bragg grating to pass through.

2. The variable range liquid level measuring device of claim 1, wherein said diaphragm area adjuster comprises: upper cover and lower cover assembled together and install flabellum and support frame in the cavity that forms after upper cover and lower cover assembled, wherein:

the fan blade comprises a plurality of blades which are distributed in the same direction, the blades are uniformly arranged at the center of the fan blade in a surrounding manner, each blade is provided with a hole, a short pin is arranged at the corresponding position of the lower cover, the blades are installed and positioned through the short pins, and the blades are installed on the lower cover through the combination of the holes and the short pins;

a guide post is arranged on one end face of each blade facing the support frame;

the support frame is ring shape, it with the flabellum is concentric, evenly seted up on its ring surface with the guide way that blade quantity is unanimous, these guide ways wind the unanimous dispersion of support frame centre of a circle orientation is used for imbedding the guide post that sets up on the blade, through can move according to the regulation orbit in groove when guide post and guide way realize the blade atress.

3. The variable range liquid level measuring device according to claim 2, wherein a notch is formed in a side surface of the upper cover, and a handle arranged on a side surface of the support frame extends out of the notch from the cavity and drives the blade to rotate under the action of external force, so that the area of the elastic diaphragm is effectively shielded.

4. The device for measuring liquid level with variable range according to any one of claims 1 to 3, wherein the circular elastic body comprises a thin-walled ring, two extending parts are symmetrically arranged on two sides of the thin-walled ring in the same horizontal direction, and the two extending parts are provided with two through holes along the horizontal direction to be communicated with the thin-walled ring;

the middle part of the thin-walled ring is transversely provided with an optical fiber Bragg grating, and two ends of a communication line for connecting the optical fiber Bragg grating respectively penetrate through holes of the two extending parts;

the upper end and the lower end of the thin-wall ring are provided with a contact part and an installation part, the lower end of the contact part penetrates through the diaphragm area regulator and the elastic diaphragm, and the installation part is used for being installed with the cover plate.

5. The variable range liquid level measurement device of claim 4, further comprising: the sensor comprises a base, a shell and a cover plate, wherein the lower end of the shell is connected with the base, the cover plate is buckled at the upper end of the shell, and the base, the shell and the cover plate are assembled together to seal all parts of the sensor.

6. The variable range liquid level measuring device according to claim 5, wherein two mounting holes are formed in the mounting portion, and the mounting portion below the cover plate and the mounting portion above the circular elastic body are fixedly mounted by two nuts.

7. The variable range fluid level gauge of claim 6, wherein the threaded connections are between the cover plate and the housing, between the diaphragm area adjuster and the housing, and between the diaphragm area adjuster and the base.

8. The variable range liquid level measuring device of claim 5, wherein there are two sets of the through posts symmetrically disposed on the upper end of the cover plate, and the lower ends of the through posts extend into the cover plate and are threadedly coupled to the cover plate.

9. The variable range liquid level measuring device of claim 5, wherein the elastic membrane is welded at both ends of the base with a certain gap between the base and the elastic membrane.

10. A variable range liquid level measuring method using the variable range liquid level measuring apparatus according to any one of claims 1 to 9, comprising the steps of:

step 1, according to actual requirements, setting the effective area of an elastic diaphragm by adjusting a diaphragm area adjuster to determine the measuring range and sensitivity of a sensor;

step 2, enabling the liquid level pressure p to act on the variable elastic diaphragm through the base, and enabling the elastic diaphragm to generate a certain amount of elastic deformation under the action of the pressure p;

step 3, transmitting the deformation of the elastic membrane to a circular elastic body connected with the elastic membrane through the compression deformation of the elastic membrane, and converting the deformation into the compression deformation of the circular elastic body;

step 4, further converting the wavelength of the Bragg grating into wavelength change of the Bragg grating;

step 5, obtaining the required variation of the liquid level pressure intensity by detecting the variation of the wavelength, and converting the obtained variation of the liquid level pressure intensity into the liquid level height;

and 6, obtaining required liquid level data through a control system and a display system.

Background

Currently, most of the implementations of the pressure sensor with adjustable measurement range mainly use the pressure sensor probe made by the regulating valve (for example, the FBG variable sensitivity pressure sensor design is selected from the 6 th page 69 to the 71 th page of volume 35 of 2006, page 6), and the main development trend is toward high precision, toward miniaturization, toward high stability and wide temperature range,

for the present situation, most pressure sensors mainly use a quantitative range pressure sensor, and many researches on a range-adjustable fiber bragg grating as a sensing element are carried out, but the practical application is few, so that the liquid level measurement system becomes an important part of a ship automation system in a plurality of ship technology systems in consideration of the premise that the ship is used for safe operation or navigation on the sea. The concept of a level measurement system has become quite rich through the last decade of development. The accuracy of the ship liquid level measurement data has a direct relation with whether the ship can safely and reliably sail on the sea. Therefore, it is necessary to design a pressure sensor with FBG fiber grating as a sensing element for measuring the liquid level of a ship.

Disclosure of Invention

The invention aims to provide a liquid level measuring device with variable range, the range is manually adjustable, accurate liquid level measurement can be performed on ocean lakes with different sea areas and different depths in a targeted manner, the flexibility is strong, the application range is wide, the cost is low, and the liquid level measuring device is very practical.

The invention also aims to provide a liquid level measuring method with variable measuring range, which utilizes the liquid level measuring device to realize the real-time measurement of the liquid level of the ship, displays the liquid level information at a specified position through a control system and a display system, monitors and pre-warns the liquid level data through the control system, and sends a warning system to pre-warns when the liquid level is higher than or lower than a preset reasonable value range, so that ship workers can intervene in time to eliminate risks, thereby ensuring the navigation safety index.

In order to further achieve the purpose, the invention adopts the following technical scheme: a variable range level gauge comprising:

the elastic diaphragm is arranged in the base and used for converting the external pressure into the elastic deformation of the diaphragm;

the diaphragm area regulator is arranged at the upper end of the elastic diaphragm and is used for realizing range adjustment by changing the effective area of the diaphragm;

the fiber Bragg grating is arranged in the middle of the circular elastic body and used for reflecting the pressure bearing size through the changed grating spacing size after stress and further converting the pressure bearing size into liquid level variation;

the lower end of the circular elastic body penetrates through the membrane area regulator and then is elastically connected with the elastic membrane, and the circular elastic body is used for transmitting the deformation of the elastic membrane to the fiber Bragg grating so as to change the distance between the gratings and further convert the change into the variation of the wavelength;

and the wire passing column is a wire passing hole of the fiber Bragg grating and is used for enabling a communication wire connected with the fiber Bragg grating to pass through.

Preferably, the diaphragm area adjuster includes: upper cover and lower cover assembled together and install flabellum and support frame in the cavity that forms after upper cover and lower cover assembled, wherein:

the fan blade comprises a plurality of blades which are distributed in the same direction, the blades are uniformly arranged at the center of the fan blade in a surrounding manner, each blade is provided with a hole, a short pin is arranged at the corresponding position of the lower cover, the blades are installed and positioned through the short pins, and the blades are installed on the lower cover through the combination of the holes and the short pins;

a guide post is arranged on one end face of each blade facing the support frame;

the support frame is ring shape, it with the flabellum is concentric, evenly seted up on its ring surface with the guide way that blade quantity is unanimous, these guide ways wind the unanimous dispersion of support frame centre of a circle orientation is used for imbedding the guide post that sets up on the blade, through can move according to the regulation orbit in groove when guide post and guide way realize the blade atress.

Preferably, the side surface of the upper cover is provided with a notch, a handle arranged on the side surface of the support frame extends out of the notch from the cavity, and the blade is driven to rotate under the action of external force, so that the area of the elastic diaphragm is effectively shielded.

Preferably, the circular elastic body comprises a thin-wall ring, two extending parts are symmetrically arranged on two sides of the thin-wall ring in the same horizontal direction, and two through holes are formed in the two extending parts along the horizontal direction and communicated with the thin-wall ring;

the middle part of the thin-walled ring is transversely provided with an optical fiber Bragg grating, and two ends of a communication line for connecting the optical fiber Bragg grating respectively penetrate through holes of the two extending parts;

the upper end and the lower end of the thin-wall ring are provided with a contact part and an installation part, the lower end of the contact part penetrates through the diaphragm area regulator and the elastic diaphragm, and the installation part is used for being installed with the cover plate.

Preferably, the method further comprises the following steps: the sensor comprises a base, a shell and a cover plate, wherein the lower end of the shell is connected with the base, the cover plate is buckled at the upper end of the shell, and the base, the shell and the cover plate are assembled together to seal all parts of the sensor.

Further, be provided with two mounting holes on the installation department, apron below with the installation department of circular elastomer top carries out fixed mounting through two nuts.

Further, threaded connections are formed between the cover plate and the housing, between the diaphragm area adjuster and the housing, and between the diaphragm area adjuster and the base.

Furthermore, the through line post is provided with two sets ofly, and the symmetric distribution is in apron upper end, just the through line post lower extreme extends to in the apron and with apron threaded connection.

Further, the elastic membrane is welded at two ends of the base, and a certain gap is formed between the base and the elastic membrane.

Correspondingly, the invention also claims a variable range liquid level measuring method, which adopts the prior variable range liquid level measuring device and comprises the following steps:

step 1, according to actual requirements, setting the effective area of an elastic diaphragm by adjusting a diaphragm area adjuster to determine the measuring range and sensitivity of a sensor;

step 2, enabling the liquid level pressure p to act on the variable elastic diaphragm through the base, and enabling the elastic diaphragm to generate a certain amount of elastic deformation under the action of the pressure p;

step 3, transmitting the deformation of the elastic membrane to a circular elastic body connected with the elastic membrane through the compression deformation of the elastic membrane, and converting the deformation into the compression deformation of the circular elastic body;

step 4, further converting the wavelength of the Bragg grating into wavelength change of the Bragg grating;

step 5, obtaining the required variation of the liquid level pressure intensity by detecting the variation of the wavelength, and converting the obtained variation of the liquid level pressure intensity into the liquid level height;

and 6, obtaining required liquid level data through a control system and a display system.

Compared with the prior art, the invention has the following beneficial effects:

(1) the thin-wall circular ring in the circular elastic body is designed mainly in consideration of the fact that the circular shape is changed into the elliptical shape after the circular elastic body is stressed, and the change is obvious. Compared with other structures such as a diamond structure, the diamond structure is still formed after the change, and the stress analysis is complicated.

(2) Compared with the design of some regulating valves, the design of the diaphragm area regulator designed by the invention is simpler in operation and more accurate in control. Because to the adjustment mechanism of general form, like valve structure, shelter from the adjustable function of range of realizing the sensor through controlling, probably there be some and control and shelter from asynchronous phenomenon, lead to measuring result can have certain error, but to the structure of diaphragm area regulator, can guarantee that every blade all shelters from in step, the effective diaphragm area of its each part is more accurate like this to make measuring result can be more accurate.

(3) Can not be influenced by factors such as electricity, magnetism and the like. When an optical signal propagates in an optical fiber, the optical fiber cannot be influenced by electromagnetic action due to the intrinsic safety characteristic of 'no electricity' of the optical fiber, so that the signal has strong resistance to electromagnetic interference in the transmission process, and the optical fiber is widely applied to an electric power system.

(4) Has strong insulation. Most of the optical fibers with excellent insulation performance are made of quartz glass which is a non-conductive non-metallic material at present, so that the measurement of various data with high-voltage electric instruments is very convenient.

(5) Has strong explosion-proof performance. Because the low-energy optical information is transmitted in the optical fiber, the safety problems such as spark, electric leakage and the like cannot be caused, and in addition, the optical fiber sensor has strong corrosion resistance, the optical fiber sensor is suitable for measuring objects which are high in environmental temperature and have corrosion.

(6) Has strong flexibility and plasticity. Because the optical fiber has the characteristic of being thin and flexible, the optical fiber sensor which is small in size, light and flexible can be manufactured, and objects which cannot be measured by a common sensor in complex occasions can be measured.

(7) The optical fiber material is simple and easy to obtain, so that the economy is good.

(8) Compared with the traditional sensor, the Fiber Bragg Grating (FBG) sensor has the characteristics of small volume, good explosion-proof performance, good insulating performance, strong toughness and plasticity and the like, and has higher cost performance.

Drawings

The accompanying drawings, which are included to provide a further understanding of the application and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the application and together with the description serve to explain the application and not to limit the application. In the drawings:

FIG. 1 is an overall external view of the variable range level gauge of the present invention;

FIG. 2 is a schematic structural view of a variable range liquid level measuring device according to the present invention;

FIG. 3 is a cross-sectional view of a variable range liquid level measuring device of the present invention;

FIG. 4 is a perspective view of the diaphragm area adjuster of the present invention;

FIG. 5 is a front, side view of the diaphragm area adjuster of the present invention;

FIG. 6 is an exploded view of the diaphragm area adjuster of the present invention;

FIG. 7 is a perspective view of a circular elastomeric body of the present invention;

FIG. 8 is a schematic view of the working principle of the circular elastic body of the present invention;

FIG. 9 is a flow chart of the measuring operation of the liquid level measuring device of the present invention.

Description of the drawings:

1. a base; 2. an elastic diaphragm; 3. 3.1 parts of a diaphragm area regulator, 3.1 parts of a handle, 3.2 parts of fan blades, 3.3 parts of a support frame, 3.4 parts of a lower cover, 3.5 parts of an upper cover, 3.6 parts of a guide column, 3.7 parts of a guide groove; 4. a fiber bragg grating; 5. a housing; 6. circular elastomer, 6.1, thin-wall ring, 6.2, extension, 6.3, contact, 6.4, mounting; 7. a cover plate; 8. and a wire passing column.

Detailed Description

For the purpose of facilitating the understanding and practice of the present invention, as will be described in further detail below with reference to the accompanying drawings and examples, it is to be understood that the examples described herein are for purposes of illustration and explanation, and are not intended to limit the invention.

Example 1.

A variable range level gauge, see fig. 1-8, comprising: the sensor comprises a base 1, a shell 5 and a cover plate 7, wherein the lower end of the shell 5 is connected with the base 1, the cover plate 7 is buckled at the upper end of the shell 5, and the base 1, the shell 5 and the cover plate 7 are assembled together to seal all parts of the sensor and protect a sensing unit in the structure.

Referring to fig. 2, the components of the closed sensor include an elastic diaphragm 2, a diaphragm area adjuster 3, a fiber bragg grating 4, and a circular elastic body 6, wherein: the elastic diaphragm 2 is arranged in the base 1, and the elastic diaphragm 2 plays a role in bearing pressure and converts external pressure into elastic deformation of the diaphragm; the diaphragm area regulator 3 is arranged at the upper end of the elastic diaphragm 2, the diaphragm area regulator 3 plays a role in regulating the effective area of the diaphragm, and the purpose of regulating the measuring range is realized by changing the effective area of the diaphragm; the Fiber Bragg Grating 4 is arranged in the middle of the circular elastic body 6, is called as Fiber Bragg Grating (FBG) for short, and is a sensitive element, the pressure bearing size is reflected by the changed Grating interval after being stressed, and the pressure bearing size is further converted into liquid level variation; the lower end of the circular elastic body 6 penetrates through the diaphragm area regulator 3 and is elastically connected with the elastic diaphragm 2, a hard core with the same size as the lower end of the circular elastic body 6 is arranged at the center of the elastic diaphragm 2, the circular elastic body 6 is seamlessly and tightly attached to the hard core, the transmission effect is achieved, the deformation of the elastic diaphragm 2 due to pressure bearing is transmitted to the grating in the circular elastic body 6, and therefore the distance between the gratings is changed and is further converted into the variation of the wavelength.

Referring to fig. 1-3, two groups of wire posts 8 are symmetrically distributed at the upper end of the cover plate 7, the lower ends of the wire posts 8 extend into the cover plate 7 and are in threaded connection with the cover plate 7, and the wire posts 8 are wire holes of optical fibers for passing through communication wires connected with the optical fibers.

Referring to fig. 4, the diaphragm area adjuster 3 includes: the fan blade assembly comprises an upper cover 3.5 and a lower cover 3.4 which are assembled together, and a fan blade 3.2 and a support frame 3.3 which are arranged in a cavity formed by assembling the upper cover 3.5 and the lower cover 3.4, wherein the upper cover 3.5 and the lower cover 3.4 are assembled to play roles of protecting and sealing the fan blade 3.2; the supporting frame 3.3 enables the fan blades to move according to a set track after being stressed so as to realize the opening/closing function of the diaphragm area regulator; the fan blade 3.2 is the main component of the opening/closing function of the diaphragm area regulator, and is convenient for realizing effective shielding of the area of the elastic diaphragm. According to the invention, the diaphragm area regulator 3 is added in the device, so that the working radius of the internal elastic diaphragm can be changed, and the function of adjusting the measuring range of the measuring device is further realized. For generally realizing the pressure sensor of range adjustable through the governing valve, on the basis of job stabilization, dependable performance, diaphragm area regulator realizes that the range to the elastic diaphragm is adjustable in this scheme of utilization, reducible damage to the diaphragm that causes in the accommodation process, the life of extension sensor, for general adjustment mechanism such as valve type structure, its shelters from the structure and directly acts on the diaphragm, it makes a round trip to slide on the diaphragm and can cause certain damage to the diaphragm, and the diaphragm area adjustment mechanism's blade all is certain arc in this scheme moves, horizontal and perpendicular two directions's component can carry out certain neutralization to frictional force, thereby reduce the friction, play the guard action to the diaphragm to a certain extent, reduce the damage of diaphragm, further prolong the life of sensor. Meanwhile, the operation is simpler and more convenient, so that the measurement efficiency is greatly improved, and the use is convenient and quick.

In the invention, in order to meet the requirements of the whole size and function of the sensor, when the structure of the diaphragm area regulator is designed, the whole structure of the diaphragm area regulator is obtained according to the factors of the installation position and the limitation of the installation space of the regulator in the sensor, the motion form, the structural support rigidity, the reduction of the friction of the motion part and the like. Meanwhile, the organic combination of the diaphragm area regulator and the structures such as the cylinder body, the elastic diaphragm, the base and the like is considered, the diaphragm area regulator is specially designed, the organic combination can guarantee the overall assembling effect and the sealing effect to the maximum extent, the measuring structure is more accurate, the error is reduced, and the measuring precision is ensured.

Referring to fig. 4-6, the fan blade 3.2 of the present invention includes a plurality of blades arranged in the same direction, the blades are uniformly arranged around the center of the fan blade, each blade is provided with a hole, a short pin is arranged at a corresponding position of the corresponding lower cover 3.4, the blades are mounted and positioned by the short pin, that is, the blades are mounted on the lower cover 3.4 by the combination of the holes and the short pins, and a guide post 3.6 is arranged on one end surface of each blade facing the support frame 3.3; the supporting frame 3.3 is in a ring shape, is concentric with the fan blade 3.2, and is uniformly provided with guide grooves 3.7 with the same number as the blades on the ring surface, and the guide grooves 3.7 are uniformly dispersed around the center of the supporting frame 3.3 and are used for being embedded into guide columns 3.6 arranged on the blades; the blade and the supporting frame 3.3 are connected with the guide groove 3.7 through the guide post 3.6. Namely, a guide post 3.6 is arranged on each blade, a corresponding guide groove 3.7 is arranged on the support frame 3.3, and the blades can move according to the specified track of the groove when stressed by the guide posts 3.5 and the guide grooves 3.7. The side of the upper cover 3.5 is provided with a notch, a handle 3.1 arranged on the side of the support frame extends out of the notch in the cavity and drives the blade to rotate under the action of external force, so that the area of the elastic diaphragm 2 is effectively shielded.

Referring to fig. 7, the circular elastic body 6 of the present invention includes a thin-walled ring 6.1, two extending portions 6.2 are horizontally and symmetrically disposed on two sides of the thin-walled ring 6.1, and the two extending portions 6.2 are provided with two through holes along the horizontal direction to communicate with the thin-walled ring 6.1; the middle part of the thin-wall ring 6.1 is transversely provided with the fiber Bragg grating 4, and two ends of a communication line for connecting the fiber Bragg grating 4 respectively penetrate through holes arranged on the two extension parts 6.2; the upper end and the lower end of the thin-wall ring 6.1 are provided with a contact part 6.3 and an installation part 6.4, the lower end of the contact part 6.3 penetrates through the membrane area regulator 3 and then is elastically connected with a hard core structure on the elastic membrane 2, and the installation part 6.4 is used for being installed with the cover plate 7. Specifically, two mounting holes are formed in the mounting portion 6.4 of the circular elastic body 6, and the mounting portion 6.4 below the cover plate 7 and above the circular elastic body 6 are fixedly mounted through two nuts. The main body structure of the round elastomer adopts the thin-wall ring with a round structure, the round elastomer is mainly made of alloy steel or stainless steel, the alloy material has rigidity to ensure consistent deformation and deformation recovery, and has good corrosion resistance, when the alloy material is under the action of external pressure, the thin-wall ring in the elastomer is changed into an oval structure, and compared with a diamond structure in some schemesThe design and the change are more obvious, and the stress analysis expression is more concise and clear. The working principle diagram of the circular elastic body in the pressure sensor is shown in figure 8, and delta l in figure 8That is, an ideal assumed condition, Δ l represents a change amount of deformation, that is, a change amount Δ l of the bottom of the circular elastic body is equal to a change amount 1/2 Δ l +1/2 Δ l of the left and right sides of the circular elastic body. According to the design, the lower end of the thin-wall circular elastic body penetrates through the membrane area regulator to be elastically connected with the hard core structure on the elastic membrane, and the other end of the thin-wall circular elastic body is fixed. In the case of a slight deformation of the elastic diaphragm, it can be assumed that the deformation in the axial direction of the optical fiber is equal to the deformation of the circular elastic body in the measured displacement direction.

In order to make the compact construction of the level measuring device possible to meet the requirements of field installation, the dimensions of the thin-walled ring 6.1 are optimized and selected. Wherein, the width b is 2.5mm, the thickness t is 1.5mm, the outer diameter of the thin-wall ring is 16mm, and the inner diameter is 14.5 mm. In the present invention, the circular elastic body is a key core structure of the liquid level measuring device, and the perspective view thereof is shown in fig. 7.

In the present invention, the screw connections are provided between the cover plate 7 and the housing 5, between the diaphragm area adjuster 3 and the housing 5, and between the diaphragm area adjuster 3 and the base 1. The elastic diaphragm 2 is welded at two ends of the base 1, and a certain gap is formed between the base 1 and the elastic diaphragm 2. Since the sensor is used in the marine field, a stricter requirement has to be put on the moisture-proof performance of the sensor, that is, a certain amount of sealant is coated on the joint as much as possible to seal the joint so as to ensure the normal use of the sensor.

Example 2.

A variable range liquid level measuring method, see fig. 1-9, comprising the steps of:

step 1, according to actual requirements, setting the effective area of an elastic diaphragm by adjusting a diaphragm area adjuster to determine the measuring range and sensitivity of a sensor;

step 2, enabling the liquid level pressure p to act on the variable elastic diaphragm through the base, and enabling the elastic diaphragm to generate a certain amount of elastic deformation (in an arched change) under the action of the pressure p;

step 3, transmitting the variable quantity to a circular elastic body connected with the elastic membrane through the compression deformation of the elastic membrane, and converting the variable quantity into the compression deformation of the circular elastic body;

step 4, further converting the wavelength of the Bragg grating into wavelength change of the Bragg grating;

step 5, obtaining the required variation of the liquid level pressure intensity by detecting the variation of the wavelength, and converting the obtained variation of the liquid level pressure intensity into the liquid level height;

and 6, obtaining required liquid level data through a control system and a display system.

In the invention, the lower end of the thin-wall circular elastic body passes through the membrane area regulator to be elastically connected with the hard core structure on the elastic membrane, and the other end of the thin-wall circular elastic body is fixed. In the case of a slight deformation of the elastic diaphragm, it can be assumed that the deformation in the axial direction of the optical fiber is equal to the deformation of the circular elastic body in the measured displacement direction.

Utilize this liquid level measurement device to realize the real-time measurement of boats and ships liquid level to show liquid level information at the assigned position through control system and display system, and monitor and the early warning by control system to liquid level data, when the liquid level is higher than or is less than predetermined reasonable value scope, send out alarm system and carry out the early warning, make boats and ships staff in time intervene, eliminate the risk, thereby make the safety index of navigation obtain the guarantee.

It should be understood that the above description of the preferred embodiments is given for clarity and not for any purpose of limitation, and that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the invention as defined by the appended claims.