Liquid level meter

Abstract

The utility model discloses a liquid level meter which comprises a shell assembly, a liquid level sensor, a liquid level sensor, a liquid level sensor, a liquid level sensor and a liquid level sensor, and the shell assembly comprises a first shell, a second shell, an air cavity, a first flow channel and a second flow channel; the first interface is respectively communicated with the air cavity and an external air source; the second interface is communicated with the first flow channel; the third interface is communicated with the second flow channel; the pressure sensor is used for detecting gas pressure difference in the first flow channel and the second flow channel; a pressure stabilizing piece is arranged in the shell assembly in a sealed mode, a throttling hole is formed in the pressure stabilizing piece, the inner diameter of the throttling hole is smaller than the inner diameter of the first flow channel and the inner diameter of the second flow channel, and gas in the gas cavity flows into the first flow channel and the second flow channel through the throttling hole. The pressure stabilizing piece is configured to be detachably arranged, and when the first shell and the second shell are separated, the pressure stabilizing piece can be taken out of the shell assembly. According to the liquid level meter, the pressure stabilizing piece is detachably arranged in the shell assembly, when the inner diameter of the throttling hole changes and the gas flow stabilizing and pressure stabilizing effect of the throttling hole becomes poor, the pressure stabilizing piece can be detached for replacement, and the detection precision of the liquid level meter is high.

Description

TECHNICAL FIELD

[0001] The utility model relates to high accuracy detects liquid technical field especially relates to a liquid level meter. BACKGROUND

[0002] The liquid level meter is suitable for semiconductor manufacturing process and chemical process, and is particularly suitable for detecting high-precision liquids such as pure water, acid, alkali and solvent that do not adhere to the detection nozzle, for example, measuring the liquid level height of sulfuric acid or hydrofluoric acid stored in a groove structure for cleaning semiconductors, and outputting in the form of an electrical signal.

[0003] The prior art patent JP3609722B2 discloses a liquid level detection device, which discloses a gas supply mechanism for supplying nitrogen or air as a liquid level detection gas connected to a supply pipe, two branch pipes connected to the supply pipe, the two branch pipes respectively provided with throttle holes, the throttle holes having the same opening area to keep the gas flow and pressure stable through the throttle holes, the ends of the two branch pipes respectively facing the inside of the chemical liquid tank, the end of one of the branch pipes extending into the chemical liquid tank to contact the liquid, the end of the other branch pipe being arranged above the chemical liquid tank and thus above the liquid without contacting the liquid, a pressure gauge connected to point A downstream of the throttle hole of the branch pipe and point B downstream of the throttle hole of the branch pipe, the pressure gauge measuring the gas pressure through point A and the gas pressure through point B and displaying the difference between the two pressures. The pressure gauge obtains the value of Pa minus the value of Pb after the measurement of point A, i.e. Pa-Pb=P3+P4, the controller subtracts the calculated pressure P4 caused by surface tension from the value P3+P4 measured by the pressure gauge to accurately identify only P3, P3 being the pressure of the liquid at the end 12a of the branch pipe, the depth of the end 12a of the branch pipe to the liquid surface 6a being determined by P3=ρgh, in the controller, the height H of the end 12a of the branch pipe from the bottom of the chemical liquid tank is input in advance, thus the liquid level height in the chemical liquid tank becomes H+h, thereby the liquid level height in the chemical liquid tank can be accurately determined, i.e. the liquid volume in the chemical liquid tank can be correctly managed, and the liquid volume in the chemical liquid tank can be accurately controlled, so that excessive or insufficient liquid can be avoided.

[0004] However, in the liquid level detection device of the above-mentioned patent, the design, manufacture and installation of the throttle hole are crucial, because the throttle hole mainly plays a role in stabilizing the gas flow and pressure, and has a great influence on the pressure detection at downstream points A and B. If the aperture of the throttle hole changes due to manufacturing and installation reasons, or if the liquid in the groove is not removed in time when the liquid level meter is suspended, the gas corrosion of the liquid that may volatilize may cause the aperture of the throttle hole to change, thereby reducing the accuracy of the entire liquid level meter and affecting use. UTILITY MODEL CONTENTS

[0005] In order to overcome the prior art, the utility model provides a liquid level meter, it is detachable sealed with pressure stabilizing piece in casing assembly, convenient pressure stabilizing piece is taken out from casing assembly and is replaced, guarantees the steady flow, steady pressure effect of throttle hole to gas, in turn guarantees the detection precision of liquid level meter.

[0006] The utility model solves technical scheme that technical problem it adopts is: a liquid level meter, include:

[0007] Casing assembly, including first casing, with detachable sealed connection's second casing of first casing, and form in the gas cavity of casing assembly inside, first flow channel and second flow channel are linked to gas cavity respectively,

[0008] First interface forms in casing assembly, and the gas source of gas cavity and outside is communicated respectively,

[0009] Second interface forms in casing assembly, and with first flow channel intercommunication,

[0010] Third interface forms in casing assembly, and with second flow channel intercommunication,

[0011] Pressure sensor is located in casing assembly, is used for detecting the pressure difference between gas pressure in first flow channel and second flow channel,

[0012] Sealed with pressure stabilizing piece in casing assembly, throttle hole is set up on pressure stabilizing piece, the inner diameter of this throttle hole is less than the inner diameter of first flow channel, second flow channel, the gas in gas cavity flows to first flow channel and second flow channel respectively via throttle hole,

[0013] The pressure stabilizing piece is configured to be detachably arranged, so that when the first casing and the second casing are separated, the pressure stabilizing piece can be taken out from the casing assembly.

[0014] The liquid level meter provided by the utility model, when the inner diameter of the throttle hole on the pressure stabilizing sheet changes due to machining reasons, installation reasons, gas corrosion caused by evaporation of the liquid to be detected, or when the cross-sectional area difference of the throttle hole of the pressure stabilizing sheet arranged close to the first flow channel and the throttle hole of the pressure stabilizing sheet arranged close to the second flow channel is large, the pressure stabilizing sheet can be separated from the first shell and the second shell and taken out from the shell assembly, the pressure stabilizing sheet is replaced, the inner diameter of the throttle hole of the new pressure stabilizing sheet is kept basically unchanged, the stable flow and stable pressure effects of the gas entering the first flow channel and the second flow channel respectively are kept unchanged, the cross-sectional area of the throttle hole close to the first flow channel and the second flow channel is kept consistent, the gas flow difference of the gas delivered to the first flow channel and the second flow channel respectively is minimized, the fluctuation of the terminal pressure fed back by the gas in the first flow channel and the second flow channel is effectively inhibited, and then the liquid level meter can guarantee high detection precision; meanwhile, the throttle hole on the pressure stabilizing sheet is simple and convenient to process, the first shell and the second shell are simple and convenient to disassemble and assemble, the pressure stabilizing sheet is simple and fast to disassemble and assemble, the pressure stabilizing sheet can be replaced, the overall service life of the liquid level meter is prolonged, even when the stable flow and stable pressure effects of the throttle hole of the pressure stabilizing sheet on the gas are poor, the whole liquid level meter does not need to be scrapped, and the use cost is greatly saved.

[0015] Further, the first flow channel and the second flow channel are located at opposite sides of the air cavity, the pressure stabilizing sheets are two and located in the air cavity, and each pressure stabilizing sheet is arranged at the junction of the first flow channel, the second flow channel and the air cavity.

[0016] In this way, after the airflow in the air cavity is divided to the opposite sides and passes through the throttle holes of each pressure stabilizing sheet, the airflow is directly and quickly stably delivered to the first flow channel and directly and quickly stably delivered to the second flow channel, so that the gas flow in the first flow channel and the second flow channel is not only relatively balanced, but also equal or close to equal, the first flow channel can accurately and stably feed back the rear-end pressure, the second flow channel can accurately and stably feed back the rear-end pressure, the pressure difference detected by the pressure sensor is accurate, and the accuracy of the liquid level calculated by the liquid level meter is higher.

[0017] Further, a flow guide limiting piece is arranged in the air cavity, two ends of the flow guide limiting piece abut against the two pressure stabilizing sheets, so that the pressure stabilizing sheets and the shell assembly are sealingly connected, the flow guide limiting piece has a flow guide channel and a hollow flow channel extending between the two ends, the hollow flow channel is connected in communication with the first interface via the flow guide channel, and the hollow flow channel is connected in communication with the throttle hole.

[0018] With this configuration, the flow guiding and limiting components ensure that the two pressure stabilizing plates are sealed and fixed in place, preventing them from shifting. This facilitates the installation and removal of the pressure stabilizing plates. At the same time, the flow guiding channel facilitates the rapid and relatively uniform delivery of gas entering from the first interface to the hollow flow channel. The gas in the hollow flow channel can be diverted and delivered more concentratedly to the two throttling orifices.

[0019] Furthermore, the flow guiding and limiting member is a cylindrical body with a hollow interior forming the hollow flow channel, and the axial projection of the hollow flow channel covers the throttling orifice. The flow guiding channel is a flow guiding groove formed by the recess of the outer wall of the flow guiding and limiting member corresponding to the first interface position; or, the flow guiding and limiting member includes a plurality of support rods, which are spaced around the outer periphery of the throttling orifice to form the hollow flow channel, and the gap between adjacent support rods forms the flow guiding channel.

[0020] This design allows for diverse implementation forms of the flow guide and limiting components. The structural design of the flow guide and limiting components makes them relatively easy to process and disassemble. Furthermore, the axial projection of the throttling orifice of the hollow flow channel covering or the support rod being located on the outer periphery of the throttling orifice ensures that the throttling orifice is not blocked by the end face of the cylindrical flow guide and limiting component or the support rod, thus ensuring that it plays a good role in stabilizing flow and pressure. At the same time, the flow guide groove, which serves as the flow guide channel, is set at the position of the first interface or the gap between the support rods, allowing the gas entering through the first interface to directly and quickly enter the hollow flow channel. This results in minimal gas flow disturbance within the hollow flow channel, adapting to different application scenarios and offering high flexibility in use.

[0021] Furthermore, a stepped surface is formed at the junction of the air cavity with the first flow channel and the second flow channel respectively, and an annular seal is provided between the pressure stabilizing plate and the stepped surface. The flow guiding and limiting member presses the pressure stabilizing plate against the annular seal in the direction of the stepped surface.

[0022] With this configuration, the flow guide and limiting component presses the pressure stabilizing plate against the annular seal in the direction of the stepped surface. The gas in the gas chamber flows out through the throttling orifice of the pressure stabilizing plate to the first and second flow channels. It will not be directly transported to the first and second flow channels through the gap between the pressure stabilizing plate and the stepped surface. The gas in the gas chamber will not leak from the outer periphery of the pressure stabilizing plate into the first and second flow channels. It can only enter the first and second flow channels through the two throttling orifices respectively. The throttling orifice of the pressure stabilizing plate has a better effect on stabilizing the flow and pressure of the gas in the gas chamber.

[0023] Furthermore, the orifice diameter is 20um-900um.

[0024] In this way, when the aperture of the throttle hole is 20-900 um, the pressure fluctuation in the first flow channel or the second flow channel is small, the pressure difference fluctuation value detected by the pressure sensor does not exceed 0.1 Pa, and the pressure is basically stable. Once the inner diameter of the throttle hole is greater than 900 um, the pressure difference fluctuation value detected by the pressure sensor is greater than 1000 Pa, which seriously affects the accuracy of the liquid level meter. When the inner diameter of the throttle hole is less than 20 um, the gas flow is small, and it takes a long time for the gas to fill the first flow channel and the second flow channel, which may cause inaccurate feedback of the liquid pressure, and the pressure sensor cannot accurately obtain the pressure difference, thereby reducing the detection accuracy of the liquid level meter.

[0025] Further, a part of the air cavity is located in the first shell, and another part of the air cavity is located in the second shell. The connection part of the first shell and the second shell is arranged to intersect the air cavity. The pressure stabilizing piece is arranged in the first shell and the second shell, respectively.

[0026] In this way, when the first shell and the second shell are connected to form the air cavity, and when the first shell and the second shell are separated to divide the air cavity, the pressure stabilizing piece can be easily disassembled and assembled.

[0027] Further, the shell assembly further comprises a third shell detachably and sealingly connected with the first shell. The connection part of the first shell and the second shell sealingly clamps one pressure stabilizing piece, and the connection part of the first shell and the third shell sealingly clamps another pressure stabilizing piece. The shell assembly has various structural forms, including a three-segment shell. Two pressure stabilizing pieces are sealingly clamped at the connection part of the adjacent two shells, thereby effectively stabilizing the flow and pressure and being simple and convenient to disassemble and assemble.

[0028] Further, the first flow channel comprises a first sub-flow channel one and a first sub-flow channel two which are perpendicular to each other, and the second flow channel comprises a second sub-flow channel one and a second sub-flow channel two which are perpendicular to each other. The first sub-flow channel one, the air cavity, and the second sub-flow channel one are coaxially arranged. The first sub-flow channel two and the second sub-flow channel two are arranged in parallel to each other. The second interface and the first sub-flow channel two are coaxially arranged, and the third interface and the second sub-flow channel two are coaxially arranged.

[0029] In this way, the structural design of the first flow channel and the second flow channel facilitates the reasonable layout of the liquid level meter. The first sub-flow channel one, the air cavity, and the second sub-flow channel one are coaxially arranged, so that the gas in the air cavity can flow and be transported directly to the first sub-flow channel one and the second sub-flow channel one. The first sub-flow channel two and the second sub-flow channel two are arranged in parallel to each other, so as to ensure that the gas flow is quickly and stably transported to the second interface or the third interface.

[0030] Further, the pressure stabilizing piece is made of metal, and the shell assembly is provided with a waterproof and breathable membrane for preventing fluid from flowing from the second interface and the third interface towards the pressure stabilizing piece.

[0031] In this way, the waterproof and breathable film is used to prevent fluid from flowing from the second interface and the third interface towards the pressure stabilizing piece, that is, to prevent corrosive liquid from corroding the metal pressure stabilizing piece when detecting the volatilization of the liquid, so as to prevent the liquid evaporation from corroding the orifice, ensure that the inner diameter of the orifice remains unchanged after the liquid level meter is used for a long time, and then ensure that the orifice effectively stabilizes the flow and pressure of the gas, and finally ensure the good detection precision of the liquid level meter.

[0032] Further, the shell assembly further has a first backup interface in communication with the first flow channel and a second backup interface in communication with the second flow channel.

[0033] In this way, the backup interfaces are used to change positions, which is convenient for connecting the liquid level detection pipe or the environment pressure detection pipe at the interfaces.

[0034] Further, the shell assembly is formed with a mounting cavity, the pressure sensor is accommodated in the mounting cavity, and a sensor PCB board electrically connected with the pressure sensor is further accommodated in the mounting cavity.

[0035] In this way, the pressure sensor is arranged in the mounting cavity in the shell assembly and is in contact with the gas in the first flow channel and the second flow channel to detect the pressure difference therebetween, and the transmitter electrically connected with the sensor PCB board is used to convert the pressure difference sensed by the pressure sensor into a liquid level height and display the liquid level height, so that the operator can directly read the data and use the liquid level meter more conveniently.

[0036] The liquid level meter has the following advantages:

[0037] 1. When the inner diameter of the throttle hole on the pressure stabilizing sheet changes due to processing reasons, installation reasons, gas corrosion caused by evaporation of the liquid to be detected, or the like, or when the throttle hole of the pressure stabilizing sheet arranged close to the first flow channel and the throttle hole of the pressure stabilizing sheet arranged close to the second flow channel have a large difference in cross-sectional area, the effect of the throttle hole on the stable flow and pressure of the gas becomes poor, the first shell and the second shell can be separated, the pressure stabilizing sheet can be removed from the shell assembly, the pressure stabilizing sheet can be replaced, the inner diameter of the throttle hole of the new pressure stabilizing sheet can be kept basically unchanged, the stable flow and pressure effect of the gas entering the first flow channel and the second flow channel can be kept unchanged, the cross-sectional area of the throttle hole close to the first flow channel and the second flow channel can be kept consistent, the difference in gas flow delivered to the first flow channel and the second flow channel can be minimized, the fluctuation of the feedback terminal pressure of the gas in the first flow channel and the second flow channel can be effectively suppressed, and then the liquid level meter can ensure high detection accuracy; at the same time, the throttle hole on the pressure stabilizing sheet is simple and convenient to process, the first shell and the second shell are simple and convenient to disassemble and assemble, the pressure stabilizing sheet is simple and fast to disassemble and assemble, the replaceable pressure stabilizing sheet can prolong the overall service life of the liquid level meter, and even when the throttle hole of the pressure stabilizing sheet has poor stable flow and pressure effect on the gas, the entire liquid level meter does not need to be scrapped, and the use cost is greatly saved.

[0038] 2. The abutment of the flow guide limiting piece with the two pressure stabilizing sheets ensures that the two pressure stabilizing sheets are stably and tightly installed in the shell assembly without deviation, facilitates the disassembly and assembly of the pressure stabilizing sheet, and the arrangement of the flow guide channel facilitates the rapid delivery of the gas entering the first interface to the hollow flow channel, and the hollow flow channel enables the gas to be more concentratedly delivered to the throttle hole for flow guiding. BRIEF DESCRIPTION OF DRAWINGS

[0039] Figure 1 A perspective view of a liquid level meter provided by the embodiment of the utility model.

[0040] Figure 2 A front view of a liquid level meter provided by the embodiment of the utility model.

[0041] Figure 3 A-A sectional view of Figure 2 .

[0042] Figure 4 A structure enlarged view of B in Figure 3 .

[0043] Figure 5 A sectional view of the part where the first interface, the second interface, and the third interface of the liquid level meter are located, which is provided by the embodiment of the utility model.

[0044] Figure 6 A structure enlarged view of B in Figure 3 , and the flow guide limiting piece is omitted at this time.

[0045] Figure 7 The utility model provides a cooperation structure perspective drawing of guide flow limiting piece, voltage stabilizing sheet, annular sealing piece provided for the utility model embodiment.

[0046] Figure 8 The utility model provides a cooperation structure main view of guide flow limiting piece, voltage stabilizing sheet, annular sealing piece provided for the utility model embodiment.

[0047] Figure 9 The utility model provides a cooperation structure section view of guide flow limiting piece, voltage stabilizing sheet, annular sealing piece provided for the utility model embodiment.

[0048] Figure 10 The utility model provides a cooperation structure perspective drawing of guide flow limiting piece, voltage stabilizing sheet provided for the utility model embodiment.

[0049] Figure 11 The utility model provides a three -dimensional of guide flow limiting piece provided for the utility model embodiment Figure 1 .

[0050] Figure 12 The utility model provides a three -dimensional of guide flow limiting piece provided for the utility model embodiment Figure 2 .

[0051] Figure 13 The utility model provides a perspective drawing of voltage stabilizing sheet provided for the utility model embodiment.

[0052] Figure 14 The utility model provides a main view of voltage stabilizing sheet provided for the utility model embodiment.

[0053] Figure 15 The utility model provides a section view of voltage stabilizing sheet provided for the utility model embodiment.

[0054] Figure 16 The utility model provides another structure cooperation structure schematic diagram of guide flow limiting piece and voltage stabilizing sheet provided for the utility model embodiment.

[0055] Figure 17 The utility model provides a partial three -dimensional of liquid level meter provided for the utility model embodiment Figure 1 , first shell is omitted at this time.

[0056] Figure 18 The utility model provides a partial three -dimensional of liquid level meter provided for the utility model embodiment Figure 2 , first shell is omitted at this time.

[0057] Figure 19 The utility model provides a partial three -dimensional of liquid level meter provided for the utility model embodiment Figure 3 , first shell is omitted at this time.

[0058] Figure 20 The utility model provides a second kind of shell assembly structure brief view provided for the utility model embodiment.

[0059] Figure 21 A third shell assembly structure schematic view provided by the embodiment of the utility model.

[0060] Figure 22 A perspective view of the transmitter provided by the embodiment of the utility model.

[0061] Wherein, 1 - shell assembly, 11 - first shell, 12 - second shell, 13 - air cavity, 131 - step surface, 14 - first flow channel, 141 - first sub-flow channel one, 142 - first sub-flow channel two, 15 - second flow channel, 151 - second sub-flow channel one, 152 - second sub-flow channel two, 16 - first spare interface, 17 - second spare interface, 18 - installation cavity, 19 - third shell, 101 - first clamping groove, 102 - second clamping groove, 103 - third clamping groove, 2 - first interface, 3 - second interface, 4 - third interface, 5 - pressure sensor, 51 - sensor PCB board, 53 - transmitter, 531 - display screen, 6 - voltage stabilizing piece, 61 - throttle hole, 7 - flow guide limiting piece, 71 - flow guide channel, 72 - hollow flow channel, 73 - support rod, 8 - annular sealing element. DETAILED DESCRIPTION

[0062] In order to make the person skilled in the art better understand the utility model scheme, below will combine the drawings in the embodiment of the utility model, the technical scheme in the embodiment of the utility model is clearly and completely described, obviously, the described embodiment is only a part of the embodiment of the utility model, not all the embodiment. Based on the embodiment in the utility model, all other embodiments obtained by the person skilled in the art without making creative labor should belong to the scope of the utility model protection.

[0063] As Figures 1-3 Shown, a liquid level gauge, including shell assembly 1, the first interface 2, the second interface 3, the third interface 4 formed in shell assembly 1, and the pressure sensor 5 arranged in the shell assembly 1, the pressure sensor 5 is used to detect the pressure difference between the gas pressure in the first flow channel 14 and the second flow channel 15.

[0064] Shell assembly 1 includes first shell 11, second shell 12 detachably sealedly connected with the first shell 11, air cavity 13 formed inside shell assembly 1, and first flow channel 14 and second flow channel 15 respectively communicated with the air cavity 13, specifically, the first shell 11 and the second shell 12 are sealed by at least one sealing ring located on the outer periphery of the air cavity 13, and the first shell 11 and the second shell 12 are fixedly connected by screws or bolts or the like fasteners, or the first shell 11 and the second shell 12 are directly threadedly connected or clamped.

[0065] The first interface 2 is in communication with the air cavity 13 and an external air source, and serves as an air inlet; the second interface 3 is in communication with the first flow channel 14, and specifically, the second interface 3 is in communication with the first flow channel 14 and a liquid level to be detected, and serves as an air outlet; and the third interface 4 is in communication with the second flow channel 15, and specifically, the third interface 4 is in communication with the second flow channel 15 and an atmospheric environment or an environment above the liquid level to be detected, and serves as another air outlet.

[0066] It should be noted that the first interface 2, the second interface 3, and the third interface 4 can be structures without joints or structures with joints. As shown in FIG. 2, the first interface 2, the second interface 3, and the third interface 4 all include joints, which can be any joint in the prior art, and the specific connection mode of the joints with the shell assembly 1 is not limited, and in this embodiment, the joints are connected by threads, and a gas inlet pipe, a liquid level detection pipe, or an environmental pressure detection pipe is sealingly connected to each joint. Figure 4 Figure 5 As shown in FIG. 3, the first interface 2, the second interface 3, and the third interface 4 all do not include joints, and the specific structure of the interfaces is only a groove or a protrusion formed by the shell assembly 1, which can be a groove structure with internal threads such as a nut, and of course, in other implementation manners, the specific structure can also be a protrusion structure with external threads, and the specific structure is not limited. The groove structure or the protrusion structure can be connected to an external joint by threads, and the joint as an external part needs to be assembled to the shell assembly 1 of the liquid level meter, and then the gas inlet pipe, the liquid level detection pipe, or the environmental pressure detection pipe is sealingly connected to the external joint. Of course, the groove or the protrusion can be directly connected to the gas inlet pipe, the liquid level detection pipe, or the environmental pressure detection pipe without an additional joint.

[0067] In this embodiment, the gas inlet pipe is sealingly connected to the first interface 2, the liquid level detection pipe is sealingly connected to the second interface 3, and the environmental pressure detection pipe is sealingly connected to the third interface 4. The gas inlet pipe is used to communicate with an air source, the liquid level detection pipe extends into the interior of a liquid level to be detected, and the environmental pressure detection pipe extends into an atmosphere or above the liquid level to be detected.

[0068] The shell assembly 1 is sealingly provided with a pressure stabilizing piece 6, and the pressure stabilizing piece 6 is provided with a throttle hole 61. The inner diameter of the throttle hole 61 is smaller than the inner diameter of the first flow channel 14 and the inner diameter of the second flow channel 15. The gas in the air cavity 13 flows into the first flow channel 14 and the second flow channel 15 through the throttle hole 61. The throttle hole 61, the first flow channel 14, and the second flow channel 15 are all circular, so the inner diameter refers to the circular diameter. The pressure stabilizing piece 6 is configured to be detachably arranged, so that when the first shell 11 and the second shell 12 are separated, the pressure stabilizing piece 6 can be taken out of the shell assembly 1.

[0069] ​The specific assembly mode of the pressure stabilizing sheet 6 is not limited here, as long as the pressure stabilizing sheet 6 can be sealed with the shell assembly 1, which can be sealed by gaskets, O-rings, abutting, etc., so that the gas entering the gas cavity 13 only flows from the throttle hole 61 to the first flow channel 14 and the second flow channel 15, avoiding part of the gas in the gas cavity 13 from flowing to the first flow channel 14 and the second flow channel 15 through the gap between the inner wall of the gas cavity 13 and the pressure stabilizing sheet 6 without passing through the throttle hole 61.

[0070] The detachable mode between the pressure stabilizing sheet 6 and the shell assembly 1 is not limited here, and the pressure stabilizing sheet 6 can be clamped or screwed in the shell assembly 1, and the detachable mode should be matched with the sealing mode described above to achieve the detachable sealing of the pressure stabilizing sheet 6 in the shell assembly 1. In addition, the thickness of the pressure stabilizing sheet 6 can be thin, which is convenient for forming the throttle hole 61 of the pressure stabilizing sheet 6. As described below, the pressure stabilizing sheet 6 is provided with two throttle holes 61, which are located on the upstream side of the first flow channel 14 and the second flow channel 15, respectively, and the gas enters the first flow channel 14 and the second flow channel 15 through the two throttle holes 61 with the same aperture. The thickness of the pressure stabilizing sheet 6 can also be relatively thick, which has only one throttle hole 61 and extends completely between the first flow channel 14 and the second flow channel 15, and the gas enters the first flow channel 14 and the second flow channel 15 through the throttle hole 61 on the pressure stabilizing sheet 6.

[0071] When the pressure stabilizing sheet 6 is separated from the first shell 11 and the second shell 12, as long as the pressure stabilizing sheet 6 can be removed from the shell assembly 1 in various ways, specifically, the shell assembly 1 can be formed by combining the first shell 11 and the second shell 12 to form the gas cavity 13, and the side wall or both ends of the gas cavity 13 have a clamping groove for clamping the pressure stabilizing sheet 6. When the pressure stabilizing sheet 6 needs to be replaced, the first shell 11 and the second shell 12 are disassembled, and the pressure stabilizing sheet 6 is taken out of the clamping groove for replacement. For example, the pressure stabilizing sheet 6 in the gas cavity 13 is inclined into the clamping groove, and then the sealing ring is used to achieve the sealing assembly of the pressure stabilizing sheet 6 and the end faces of the clamping groove on both sides of the pressure stabilizing sheet 6. For example, an elastic sealing member is directly arranged on the outer ring of the pressure stabilizing sheet 6, and the elastic sealing member is sealed and assembled into the clamping groove by using the deformation performance of the elastic sealing member.

[0072] When the external gas source delivers gas into the gas cavity 13 through the first interface 2, the gas in the gas cavity 13 is delivered to the first flow channel 14 and the second flow channel 15 through the throttle hole 61 of the pressure stabilizing sheet 6 respectively. Since the inner diameter of the throttle hole 61 is smaller than the inner diameters of the first flow channel 14 and the second flow channel 15, or in other words, the inner diameter of the throttle hole 61 is much smaller than the inner diameters of the first flow channel 14 and the second flow channel 15, the gas flow through the throttle hole 61 is relatively stable and will not fluctuate greatly, and the terminal pressure feedback by the gas in the first flow channel 14 and the second flow channel 15 is stable and will not fluctuate greatly, that is, the pressure at the bottom end of the liquid level detection tube feedback by the first flow channel 14 is stable, and the atmospheric pressure or the environmental pressure above the liquid to be detected feedback by the environmental pressure detection tube is stable, so that the final liquid level detection result of the liquid level meter is accurate.

[0073] The liquid level meter provided by the embodiment of the utility model, the pressure stabilizing sheet 6 is set separately relative to the shell assembly 1, and the pressure stabilizing sheet 6 is detachably and sealingly arranged in the shell assembly 1. When the inner diameter of the throttle hole 61 of the pressure stabilizing sheet 6 changes, the throttle hole 61 of the pressure stabilizing sheet 6 deteriorates in the effect of stabilizing the gas flow, or in other words, the throttle hole 61 of the pressure stabilizing sheet 6 arranged close to the first flow channel 14 and the throttle hole 61 of the pressure stabilizing sheet 6 arranged close to the second flow channel 15 greatly differ in cross-sectional area due to reasons such as machining, installation, gas corrosion caused by evaporation of the liquid to be detected, the first shell 11 and the second shell 12 can be separated, the pressure stabilizing sheet 6 can be taken out from the shell assembly 1, and the pressure stabilizing sheet 6 can be replaced, so that the inner diameter of the throttle hole 61 is kept unchanged, the effect of stabilizing the gas flow is kept unchanged, the cross-sectional area of the throttle hole 61 of the pressure stabilizing sheet 6 arranged close to the first flow channel 14 and the second flow channel 15 is kept consistent, the difference in gas flow delivered to the first flow channel 14 and the second flow channel 15 is minimized, and the liquid level meter can ensure high detection accuracy. Compared with the throttle hole arranged on the branch pipe in the prior art, the throttle hole 61 of the pressure stabilizing sheet 6 is easier to process and replace.

[0074] Since the shell assembly 1 includes the first shell 11 and the second shell 12, the first shell 11 and the second shell 12 are easy to disassemble and assemble, and the pressure stabilizing sheet 6 is easy to replace. Generally, since the throttle hole 61 is subjected to accelerated passing of the gas and reverse corrosion of the vapor of the liquid to be detected for a long time, the throttle hole 61 is most likely to deteriorate in effect, and the effect of the throttle hole 61 directly affects the service life of the liquid level meter. The replaceable pressure stabilizing sheet 6 prolongs the overall service life of the liquid level meter. Even if the effect of the throttle hole 61 of the pressure stabilizing sheet 6 in stabilizing the gas flow deteriorates, the entire liquid level meter does not need to be scrapped, and the use cost is greatly saved.

[0075] Specifically, in the embodiment, as shown in Figure 4 , Figure 6As shown, the first flow channel 14 and the second flow channel 15 are respectively located at opposite sides of the air cavity 13, the number of the pressure stabilizing pieces 6 is two, both of the pressure stabilizing pieces 6 are arranged in the air cavity 13, and one of the pressure stabilizing pieces 6 is arranged at the junction of the first flow channel 14 and the air cavity 13, and the other pressure stabilizing piece 6 is arranged at the junction of the second flow channel 15 and the air cavity 13. The space occupied by the two pressure stabilizing pieces 6 and the space between the two pressure stabilizing pieces 6 is defined as the air cavity 13, and the space on the other side of the pressure stabilizing piece 6 is the first flow channel 14 or the second flow channel 15. After the airflow in the air cavity 13 passes through the throttling hole 61 of the pressure stabilizing piece 6, it is directly and quickly stably transported to the first flow channel 14, and also directly and quickly stably transported to the second flow channel 15, so that the gas flow in the first flow channel 14 and the second flow channel 15 is not only relatively balanced, but also equal or close to equal, and the feedback terminal pressure in the first flow channel 14 and the second flow channel 15 also tends to be stable, and the accuracy of the liquid level meter in finally calculating the liquid level is higher.

[0076] In the embodiment, in order to facilitate the installation and fixation of the pressure stabilizing piece 6, a flow guiding limiting piece 7 is arranged in the air cavity 13, both ends of the flow guiding limiting piece 7 abut against the two pressure stabilizing pieces 6 respectively, so that the pressure stabilizing piece 6 and the shell assembly 1 are sealingly connected. The flow guiding limiting piece 7 extrudes the two pressure stabilizing pieces 6 towards the two end faces of the air cavity 13 respectively, so that one of the pressure stabilizing pieces 6 is stably and sealingly fixed at the junction of the air cavity 13 and the first flow channel 14, and the other pressure stabilizing piece 6 is stably and sealingly fixed at the junction of the air cavity 13 and the second flow channel 15, and neither of them will be deviated, when the first shell 11 and the second shell 12 move in opposite directions and separate to a certain extent, the flow guiding limiting piece 7 in the air cavity 13 can be taken out, and when the two pressure stabilizing pieces 6 lose abutment, they can also be taken out from the air cavity 13 respectively.

[0077] More specifically, as shown in Figure 6 The junction of the air cavity 13 and the first flow channel 14 forms a stepped surface 131, and the junction of the air cavity 13 and the second flow channel 15 also forms a stepped surface 131, as shown in Figure 4As shown, when the flow guiding and limiting component 7 squeezes the two pressure stabilizing plates 6 toward the stepped surfaces 131 at both ends of the air chamber 13, an annular seal 8 is also provided between the pressure stabilizing plate 6 and the stepped surface 131. To be precise, the flow guiding and limiting component 7 presses the pressure stabilizing plate 6 against the annular seal 8 in the direction of the stepped surface 131. The annular seal 8 can be an O-ring or an annular gasket. The annular seal 8 deforms to seal, so that the gas in the gas chamber 13 flows out to the first flow channel 14 or the second flow channel 15 through the throttling hole 61 of the pressure stabilizer 6. It will not be directly transported to the first flow channel 14 or the second flow channel 15 through the gap between the pressure stabilizer 6 and the stepped surface 131. That is, the gas in the gas chamber 13 will not leak from the outer periphery of the pressure stabilizer 6 to the first flow channel 14 or the second flow channel 15. It can only enter the first flow channel 14 and the second flow channel 15 through the two throttling holes 61. The throttling hole 61 of the pressure stabilizer 6 has a better effect on the flow and pressure stabilization of the gas in the gas chamber 13.

[0078] The flow guide and limiting component 7 has a flow guide channel 71 and a hollow flow channel 72 extending between its two ends. The hollow flow channel 72 is connected to the first interface 2 via the flow guide channel 71 and is also connected to the throttling orifice 61. In addition to facilitating the installation and removal of the two pressure stabilizing plates 6, the flow guide and limiting component 7 also serves as a flow guide. After the gas from the external gas source enters the first interface 2, it flows through the flow guide channel 71, then through the hollow flow channel 72, and finally through the throttling orifice 61 to the first flow channel 14 and the second flow channel 15 respectively. It is not required that all the gas entering the first interface 2 flows to the hollow flow channel 72. In actual use, most of the gas flows to the hollow flow channel 72. Even if some gas flows to the space between the inner wall of the gas chamber 13 and the flow guide and limiting component 7, it cannot bypass the throttling orifice 61 and flow directly to the first flow channel 14 and the second flow channel 15 due to the obstruction of the annular seal 8.

[0079] Specifically, such as Figures 10-12 As shown, the air chamber 13 is cylindrical, the pressure stabilizing plate 6 is a circular structure adapted to the inner diameter of the air chamber 13, and the flow guiding and limiting member 7 is cylindrical. The outer diameter of the flow guiding and limiting member 7 is slightly smaller than the inner diameter of the air chamber 13, which facilitates the assembly of the flow guiding and limiting member 7 into the air chamber 13. At the same time, it will not shake radially in the air chamber 13, and will not adversely affect the flow of gas. Moreover, the amount of gas accumulating on the outer wall of the flow guiding and limiting member 7 and the inner wall of the air chamber 13 is small, ensuring that a large amount of gas can be guided to the throttling orifice 61.

[0080] The inside of the flow guide limiting piece 7 is hollow to form a hollow flow channel 72, and the axial projection of the hollow flow channel 72 covers the throttling hole 61, in other words, the outer circle of the throttling hole 61 is within the inner circle of the hollow flow channel 72, and no part of the throttling hole 61 is blocked by the end face of the flow guide limiting piece 7. In the embodiment, the hollow flow channel 72 is concentrically and coaxially arranged with the flow guide limiting piece 7, and the throttling hole 61 is concentrically and coaxially arranged with the pressure stabilizing piece 6. Therefore, as shown in Figures 7-9 , when the flow guide limiting piece 7 and the two pressure stabilizing pieces 6 are assembled in the air cavity 13, the hollow flow channel 72 and the throttling hole 61 are concentrically and coaxially arranged.

[0081] In the embodiment, the flow guide channel 71 is a flow guide groove recessed at the position of the outer wall of the flow guide limiting piece 7 corresponding to the first interface 2. Specifically, as shown in Figures 7-12 , the flow guide channel 71 includes two radially symmetrical flow guide grooves, which extend along the axial and radial directions of the flow guide limiting piece 7, and the cross section is in the shape of a circular arc, and the inner side is in communication with the hollow flow channel 72, so that the gas entering the first interface 2 can directly and quickly enter the flow guide channel 71, and the gas entering the flow guide channel 71 can flow to the hollow flow channel 72 at various positions around the hollow flow channel 72, so that the gas flow in the hollow flow channel 72 is disturbed little. In the embodiment, the flow guide groove is arranged at the middle of the length of the flow guide limiting piece 7, and correspondingly, the first interface 2 is also in communication with the middle region of the air cavity 13 to correspond to the position of the flow guide groove, so that the gas in the air cavity 13 flows more evenly to the first flow channel 14 and the second flow channel 15.

[0082] In other embodiments, as shown in Figure 16 , the flow guide limiting piece 7 includes a plurality of support rods 73, the end face of each support rod 73 is respectively in abutment with the upper and lower pressure stabilizing pieces 6, and the plurality of support rods 73 are arranged in a spaced manner around the outer periphery of the throttling hole 61, so that the internal space surrounded by the plurality of support rods 73 is the hollow flow channel 72, and the gap between adjacent support rods 73 is the flow guide channel 71. Of course, the flow guide limiting piece 7 can also have other structures, which are not limited in particular.

[0083] As shown in Figures 13-15 , the pressure stabilizing piece 6 is in the shape of a flat circular disc, which is made of metal material, and the hole diameter of the throttling hole 61 is 20um-900um, that is, Figure 15The inner diameter of the throttle hole 61 is crucial to the gas pressure in the flow channel. When the inner diameter of the throttle hole 61 is 20-900 um, the pressure fluctuation in the first flow channel 14 or the second flow channel 15 is small, and the pressure difference fluctuation value will not exceed 0.1 Pa. Once the inner diameter of the throttle hole 61 exceeds 900 um, the first flow channel 14 or the second flow channel 15 is greatly affected by the inlet pressure of the gas source, and the pressure fluctuation in the first flow channel 14 or the second flow channel 15 is large. The pressure difference fluctuation value detected by the pressure sensor 5 is greater than 1000 Pa, which seriously affects the accuracy of the liquid level meter. When the inner diameter of the throttle hole 61 is less than 10 um, the flow of the gas is too small, and it takes a long time for the gas to fill the first flow channel 14 and the second flow channel 15, which may cause inaccurate feedback of the liquid pressure, and the pressure sensor cannot accurately obtain the pressure difference, and the accuracy of the liquid level meter is reduced.

[0084] The number of throttle holes 61 of the pressure stabilizing piece 6 is one. Of course, in other embodiments, the number of throttle holes 61 of a single pressure stabilizing piece 6 can also be two or more than three, which is not limited in particular. However, the flow area of all throttle holes 61 should meet the stable pressure and stable flow effect after the gas passes through.

[0085] The space occupied by the two pressure stabilizing pieces 6 and the space between the two pressure stabilizing pieces 6 is defined as the air cavity 13. However, the distribution of the air cavity 13 in the first shell 11 and the second shell 12 is not limited. In this embodiment, part of the air cavity 13 is located in the first shell 11, and the other part is located in the second shell 12, that is, the air cavity 13 is spliced by two grooves. The connection part of the first shell 11 and the second shell 12 is arranged to intersect the air cavity 13, and the two pressure stabilizing pieces 6 are respectively arranged in the first shell 11 and the second shell 12. When the first shell 11 and the second shell 12 are separated, the air cavity 13 is opened and the pressure stabilizing piece 6 and the flow guiding and limiting piece 7 can be taken out.

[0086] More specifically, as Figure 1 、 Figure 2 、 Figure 6 、 Figures 17-19As shown, the second interface 3 is located in the first shell 11, the first interface 2 and the third interface 4 are located in the second shell 12, the first shell 11 and the second shell 12 are vertically spliced, and a sealing ring is arranged at the splicing position to realize sealed connection. During assembly, the annular sealing member 8 and one of the pressure stabilizing pieces 6 are sequentially arranged in a part of the air cavity 13 from the opening of the first shell 11 towards the second shell 12, the annular sealing member 8 and the other pressure stabilizing piece 6 are sequentially arranged in another part of the air cavity 13 from the opening of the second shell 12 towards the first shell 11, and the flow guiding limiting member 7 is arranged between the first shell 11 and the second shell 12, and then the first shell 11 and the second shell 12 are spliced and sealed to complete assembly. When the first shell 11 and the second shell 12 are connected by bolt fastening, the faces of the two pressure stabilizing pieces 6 away from the annular sealing member 8 are respectively abutted by the two ends of the flow guiding limiting member 7, and the assembly is simple. Therefore, in the embodiment, the shell assembly is a two-section shell structure, and the flow guiding limiting member 7 is needed to support and extrude, and the flow guiding limiting member 7 also guides flow.

[0087] Of course, as Figure 20 shown, in other embodiments, the shell assembly 1 can include a first shell 11, a second shell 12 and a third shell 19 which are detachably connected, the connecting position of the first shell 11 and the second shell 12 detachably clamps one of the pressure stabilizing pieces 6, the connecting position of the first shell 11 and the third shell 19 detachably clamps the other pressure stabilizing piece 6. Specifically, a first clamping groove 101 for arranging the annular sealing member 8 and the pressure stabilizing piece 6 is arranged between the first shell 11 and the second shell 12, and a second clamping groove 102 for arranging the annular sealing member 8 and the pressure stabilizing piece 6 is arranged between the first shell 11 and the third shell 19. The first clamping groove 101 can be formed by splicing the first shell 11 and the second shell 12, or the first clamping groove 101 can be completely arranged in the first shell 11 or the second shell 12. The second clamping groove 102 can be formed by splicing the first shell 11 and the third shell 19, or the second clamping groove 102 can be completely arranged in the first shell 11 or the third shell 19. Therefore, the shell assembly is a three-section shell structure, and the pressure stabilizing piece 6 and the annular sealing member 8 are clamped by adjacent two shells, so that the flow guiding limiting member is not needed to support and extrude the pressure stabilizing piece.

[0088] As Figure 21As shown, in other embodiments, the shell assembly 1 comprises a first shell 11 and a second shell 12 which are detachably connected, unlike the structure in which a part of the air cavity 13 is located in the first shell 11 and another part is located in the second shell 12, in the present embodiment structure, the air cavity 13 is located in the second shell 12 as a whole, the annular sealing element 8 and one pressure stabilizing sheet 6 are placed on the stepped surface 131 in the second shell 12, the annular sealing element 8 and another pressure stabilizing sheet are placed in the third clamping groove 103 of the second shell 12, at this time, the outer diameters of the two pressure stabilizing sheets 6 are different, but the inner diameters of the throttling holes thereof are the same. Of course, the third clamping groove 103 can also be arranged in the first shell 11, at this time, most of the air cavity 13 is located in the second shell 12, and a small part is located in the first shell 11, so the distribution of the part of the air cavity 13 is not specifically limited.

[0089] In summary, the specific structure of the shell assembly 1 is not limited, as long as the pressure stabilizing sheet 6 can be detached from the shell assembly 1, so as to facilitate the replacement of the pressure stabilizing sheet 6. The sealing connection structure between the first shell 11 or the second shell 12 or the third shell 19 is not limited, which can be that the inner circles of two of them are sealed by a sealing ring, the sealing ring is located on the outer circumferential side of the air cavity 13, to prevent the gas in the air cavity 13 from leaking to the outside of the shell assembly 1, and the outer circles of two of them are further sealed by an annular sealing element, to realize an inner-outer double-layer sealing structure.

[0090] As shown in Figure 2 , Figure 6 , the first flow channel 14 comprises a first sub-flow channel one 141 and a first sub-flow channel two 142 which are perpendicular to each other, the second interface 3 is arranged concentrically and coaxially with the first sub-flow channel one 141, the second flow channel 15 comprises a second sub-flow channel one 151 and a second sub-flow channel two 152 which are perpendicular to each other, the third interface 4 is arranged concentrically and coaxially with the second sub-flow channel two 152, the first sub-flow channel one 141, the air cavity 13 and the second sub-flow channel one 151 are coaxially arranged, so that the gas in the air cavity 13 can be directly conveyed to the first sub-flow channel one 141 and the second sub-flow channel one 151, avoiding the instability of the conveying gas flow caused by the interference or blockage of the intermediate components. The first sub-flow channel two 142 and the second sub-flow channel two 152 are arranged in parallel to each other, which can also ensure that the gas flow is quickly and stably conveyed to the second interface 3 or to the third interface 4. As shown in Figure 2 , the first interface 2, the second interface 3 and the third interface 4 are located on the same side of the shell assembly 1 in the vertical height direction.

[0091] A waterproof and breathable film (not shown in the figure) is arranged in the shell assembly 1, which can be welded on the stepped surface 131 of the first shell 11 and the stepped surface 131 of the second shell 12 and located on the side of the pressure stabilizing sheet 6 away from the air cavity 13. Since the pressure stabilizing sheet 6 is made of metal, the waterproof and breathable film is used to prevent fluid from flowing from the second interface 3 and the third interface 4 to the pressure stabilizing sheet 6, that is, to prevent corrosive liquid volatilized from the detection liquid from flowing to the air cavity 13 through the second interface 3 and the third interface 4 and finally corroding the pressure stabilizing sheet 6, thereby preventing liquid corrosion of the orifice 61, ensuring that the inner diameter of the orifice 61 remains unchanged after the liquid level meter is used for a long time, and then ensuring that the orifice 61 effectively stabilizes the flow and pressure of the gas, and finally ensuring good detection accuracy of the liquid level meter.

[0092] As shown in Figure 3 , the shell assembly 1 also has a first backup interface 16 in communication with the first flow channel 14 and a second backup interface 17 in communication with the second flow channel 15. In the non-use state of the two backup interfaces, the first backup interface 16 and the second backup interface 17 are both sealed with plugs. In this way, the position can be easily exchanged for use, and the liquid level detection tube or the environmental pressure detection tube can be conveniently connected. The liquid level detection tube or the environmental pressure detection tube is not connected on the same side of the first interface 2, that is, the side where the first interface 2 is arranged is not convenient or has no space to connect the liquid level detection tube or the environmental pressure detection tube. At this time, the first backup interface 16 or the second backup interface 17 can be used, and the second interface 3 and the third interface 4 are sealed with plugs at this time.

[0093] As shown in Figure 3 , the shell assembly 1 forms a mounting cavity 18 in which the pressure sensor 5 is accommodated, in other words, the pressure sensor 5 is arranged in the shell assembly 1. The pressure sensor 5 realizes contact sensing of the gas pressure difference between the first flow channel 14 and the second flow channel 15, and the sensing result is more accurate. The mounting cavity 18 also accommodates a sensor PCB board 51 electrically connected to the pressure sensor 5. The sensor PCB board 51 is connected to the pressure sensor 5 through a flexible flat cable or directly welded. Direct welding can save materials, the positioning after welding is reliable, and the risk of shaking is reduced. The two are connected through a flexible flat cable, the yield is high, and the manufacturing difficulty is reduced.

[0094] As shown in Figure 22 , the liquid level meter also includes a transmitter 53 arranged outside the shell assembly 1 and electrically connected to the sensor PCB board 51. The transmitter 53 includes a processing PCB board and a display screen 531. In this embodiment, the sensor PCB board 51 transmits the pressure difference to the processing PCB board in the form of an electrical signal, and the processing PCB board calculates the height and displays it through the display screen 531. Therefore, the transmitter 53 converts the pressure difference detected by the pressure sensor 5 into a liquid level height and displays it.

[0095] The utility model discloses a liquid level meter mainly used for detecting the liquid level height of semiconductor cleaning liquid in a liquid tank, a first interface 2 is an air inlet, which is used for connecting an external air source and an air cavity 13, a second interface 3 is sealingly connected with a liquid level detection tube, the liquid level detection tube is used for extending into the liquid in the liquid tank, the bottom end of the liquid level detection tube is the liquid level point to be detected, the gas in the first flow channel 14 comes out of the bottom end of the liquid level detection tube to make the liquid bubble, so that the gas in the first flow channel 14 feeds back the pressure of the liquid level point to be detected, and the third interface 4 is selected according to the specific application of the liquid level meter, for example, in the first application, the third interface 4 can be connected with the atmosphere, that is, the third interface 4 is open to the atmospheric environment, or in the second application, an environmental pressure detection tube is sealingly connected to the third interface 4, and the environmental pressure detection tube extends into the region above the liquid in the closed liquid tank, so that the gas in the second flow channel 15 feeds back the environmental pressure above the liquid to be detected.

[0096] In use, external compressed air or nitrogen enters the flow guide channel 71 through the first interface 2, enters the hollow flow channel 72, and then is divided into two streams, one of which enters the first flow channel 14 under the flow stabilizing effect of the throttle hole 61 on one of the pressure stabilizing sheets 6, and then flows into the liquid level point position to be detected in the liquid tank to bubble, so that the gas pressure in the first flow channel 14 is fed back as the total pressure of the liquid level point to be detected in the liquid, which is detected by the pressure sensor 5, wherein the total pressure of the liquid level point to be detected includes the liquid pressure and the environmental pressure / atmospheric pressure on the P point position, and the other stream enters the second flow channel 15 under the flow stabilizing effect of the throttle hole 61 on the other pressure stabilizing sheet 6, and then flows into the environment / atmosphere, so that the gas pressure in the second flow channel 15 is fed back as the environmental / atmospheric pressure and is detected by the pressure sensor 5, so that the pressure sensor 5 obtains the substantial meaning of the gas pressure difference in the first flow channel 14 and the second flow channel 15 as only the liquid pressure of the liquid level point to be detected in the liquid, and the specific detection conversion principle is not described here, which is described in detail in the prior art.

[0097] The above specific embodiment is used to explain and illustrate the utility model, rather than limit the utility model, and any modification and change made to the utility model falls within the protection scope of the utility model.

Claims

1. A liquid level gauge, characterized in that The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device.

2. The liquid level gauge of claim 1, wherein: The application relates to a pressure stabilizing device.

3. The liquid level gauge of claim 2, wherein: The application relates to a pressure stabilizing device.

4. The liquid level gauge of claim 3, wherein: The application relates to a pressure stabilizing device.

5. The liquid level gauge of claim 3, wherein: The application relates to a pressure stabilizing device.

6. The liquid level gauge of claim 1, wherein: The application relates to a pressure stabilizing device.

7. The liquid level gauge of claim 1, wherein: The application relates to a pressure stabilizing device.

8. The liquid level gauge of claim 2, wherein, The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing device. The application relates to a pressure stabilizing 9. The liquid level gauge of claim 1, wherein: The first flow channel comprises first sub-flow channel one and first sub-flow channel two which are perpendicular to each other, the second flow channel comprises second sub-flow channel one and second sub-flow channel two which are perpendicular to each other, the first sub-flow channel one, the air cavity and the second sub-flow channel one are coaxially arranged, the first sub-flow channel two and the second sub-flow channel two are arranged in parallel, the second interface and the first sub-flow channel two are coaxially arranged, and the third interface and the second sub-flow channel two are coaxially arranged.

10. The liquid level gauge of claim 1, wherein: The pressure stabilizing piece is made of metal, and the shell assembly is provided with a waterproof and breathable film for preventing fluid from flowing from the second interface and the third interface to the pressure stabilizing piece. Alternatively, the shell assembly further has a first backup interface in communication with the first flow channel and a second backup interface in communication with the second flow channel. Alternatively, the shell assembly is formed with a mounting cavity, the pressure sensor is accommodated in the mounting cavity, and the mounting cavity further accommodates a sensor PCB board electrically connected to the pressure sensor, and the liquid level meter further comprises a transmitter arranged outside the shell assembly and electrically connected to the sensor PCB board, the transmitter being used for converting the pressure difference of the pressure sensor into a liquid level height and displaying.

Images