An inductive pressure transmitter

Abstract

The utility model discloses an inductance type pressure transmitter, including transmitter main part, the sealed medium filling chamber and high pressure fluid chamber of isolated inside of transmitter main part have, be provided with the pressure deformation diaphragm between medium filling chamber and high pressure fluid chamber, be used for filling liquid medium in medium filling chamber, high pressure fluid chamber is used for the fluid of intercommunication to be measured, the pressure deformation diaphragm can occur deformation because of the pressure difference value change between medium filling chamber and high pressure fluid chamber, displacement detection subassembly is installed in medium filling chamber, displacement detection subassembly includes the inductor coil and the magnetic core of the activity of being worn in the inductor coil, the magnetic core is connected on the pressure deformation diaphragm, the utility model has the beneficial effect that: stable, high accuracy measure fluid pressure.

Description

Technical Field

[0001] This utility model relates to the field of pressure transmitter technology, specifically to an inductive pressure transmitter. Background Technology

[0002] In numerous fields such as industrial production, energy and chemical engineering, and water conservancy projects, pressure is a key parameter for measuring the operating status of a system. Pressure transmitters, as core devices that convert pressure signals into standard electrical signals, are widely used for measuring fluid pressure in pipelines. Currently, capacitive pressure transmitters dominate the industrial field. They work by causing pressure to deform an elastic diaphragm, changing the distance between the plates or the area of ​​the plates facing each other, and thus reflecting the pressure value through changes in capacitance. However, capacitive structures have inherent drawbacks: firstly, they have weak resistance to electromagnetic interference. In strong electromagnetic field environments (such as near motor clusters or high-frequency equipment), the signal is easily affected by interference and fluctuations, leading to low measurement accuracy; secondly, they have limited temperature adaptability. Temperature changes significantly affect the dielectric constant between the plates, requiring complex temperature compensation circuits to maintain accuracy.

[0003] In contrast, inductive pressure transmitters convert pressure changes into mechanical displacement through an elastic element. This displacement then alters the relative position of the inductor coil and the iron core in the magnetic circuit, causing a change in the coil's inductance. Finally, the circuit converts this inductance change into a transmittable electrical signal, enabling indirect pressure measurement. Inductive pressure transmitters operate based on the principle of electromagnetic induction. Thanks to their magnetic circuit structure, changes in inductance are less affected by electromagnetic interference, and they also exhibit superior magnetic permeability stability over a wide temperature range. Utility Model Content

[0004] In view of this, the present invention provides an inductive pressure transmitter that can stably and accurately measure fluid pressure.

[0005] To achieve the above objectives, the technical solution of this utility model is as follows:

[0006] An inductive pressure transmitter includes a transmitter body with a sealed, isolated media-filled chamber and a high-pressure fluid chamber inside. A pressure-deformable diaphragm is disposed between the media-filled chamber and the high-pressure fluid chamber. The media-filled chamber is used to fill a liquid medium, and the high-pressure fluid chamber is used to connect to the fluid to be measured. The pressure-deformable diaphragm can deform due to changes in the pressure difference between the media-filled chamber and the high-pressure fluid chamber. A displacement detection component is installed in the media-filled chamber. The displacement detection component includes an induction coil and a magnetic core that is movably inserted into the induction coil. The magnetic core is connected to the pressure-deformable diaphragm.

[0007] Using the above structure, the fluid pressure is converted into the linear displacement of the magnetic core through the pressure-deformed diaphragm. The mechanical displacement is converted into inductive change by the principle of electromagnetic induction. Compared with the capacitive structure, the influence of electromagnetic interference on the measurement signal is avoided in principle. At the same time, by taking advantage of the temperature stability of magnetic permeability, stable and high-precision measurement of fluid pressure can be achieved.

[0008] Preferably, the transmitter body includes a base, and a left template and a right template installed at the left and right ends of the base. The base has a cavity that extends through the thickness direction. The displacement detection component and the pressure-deformed diaphragm are respectively installed at the left and right ends of the cavity.

[0009] A left elastic isolation diaphragm and a right elastic isolation diaphragm are respectively installed at the left and right ends of the base. A low-pressure fluid chamber is formed between the left elastic isolation diaphragm and the left template. The high-pressure fluid chamber is formed by the right elastic isolation diaphragm and the right template. The low-pressure fluid chamber is used to connect to the fluid to be measured. With the above structure, the structure is compact, and the high-pressure fluid chamber and the low-pressure fluid chamber can be connected to fluids of different pressures to achieve differential pressure measurement.

[0010] Preferably, a transmission chamber is formed between the pressure-deformable diaphragm and the right elastic isolation diaphragm, and the transmission chamber is filled with a liquid medium. With this structure, the liquid medium has stable pressure transmission characteristics, ensuring that pressure is transmitted to the pressure-deformable diaphragm without lag.

[0011] Preferably, a partition is fixedly installed within the transmission chamber, and a through hole along its thickness is formed in the middle of the partition. The through hole includes a narrow section and a wide section, with the narrow section facing the right elastic isolation diaphragm and the wide section facing the pressure-deformable diaphragm. This structure optimizes the efficiency and stability of pressure transmission.

[0012] Preferably, the pressure-deformable diaphragm includes a centrally planar stress-bearing area and several concentric annular corrugations extending continuously outward from the stress-bearing area, with the stress-bearing area directly opposite the through hole. Using this structure, the corrugated structure can increase elastic deformation.

[0013] Preferably, the induction coil has an inner cavity extending through it along its axial direction, and the magnetic core is reciprocally slidably disposed within the inner cavity. One end of the magnetic core is connected to a connecting rod extending outward from the inner cavity, and the outer end of the connecting rod is provided with a supporting step; the outer end face of the supporting step is fixedly connected to the stress area. This structure facilitates connection, and the minute deformation of the pressure-deformed diaphragm can be synchronously and without deviation transmitted to the induction coil by the magnetic core.

[0014] Preferably, the pressure-deformable diaphragm has annular gaskets on both sides, which are stacked and welded together to form a whole within the cavity. This structure reduces the likelihood of the pressure-deformable diaphragm being welded through.

[0015] Preferably, a left medium chamber is provided between the left elastic isolation diaphragm and the left end of the base, and a right medium chamber is provided between the pressure-deformed diaphragm and the right end of the base. The left medium chamber and the right medium chamber are connected through the inner cavity, which is directly opposite the center of the left elastic isolation diaphragm.

[0016] The base has a channel running through it along its axial direction, connecting the left and right media chambers. This structure ensures that the pressure difference is uniformly transmitted to the relevant components, reducing measurement errors caused by uneven pressure transmission and improving the overall accuracy of differential pressure measurement.

[0017] Preferably, the left end face of the base is provided with a first groove, the bottom shape of which is adapted to the left elastic isolation diaphragm.

[0018] The right end face of the partition plate has a second groove whose bottom is adapted to the right elastic isolation diaphragm. This structure provides mechanical restraint under overpressure conditions, preventing permanent damage to the isolation diaphragm due to excessive deformation.

[0019] Preferably, the base has mounting holes along its radial direction, and an electrical connection socket is installed in the mounting holes. This structure provides a compact layout, meeting the installation requirements of confined spaces.

[0020] Compared with the prior art, the beneficial effects of this utility model are:

[0021] 1. The inductive pressure transmitter provided by this utility model converts the pressure of the fluid to be measured into the linear displacement of the magnetic core through a pressure-deformable diaphragm. The stable conversion of inductance is achieved by utilizing the relative position change between the induction coil and the magnetic core, thus fundamentally avoiding the signal fluctuation problem caused by electromagnetic interference in capacitive transmitters. Simultaneously, the magnetic permeability in the magnetic circuit structure is minimally affected by temperature, and the corrugated structure of the pressure-deformable diaphragm is designed to adapt to temperature deformation, enabling stable and high-precision measurement of fluid pressure.

[0022] 2. The pressure-deformable diaphragm adopts a design with a central planar stress zone and several concentric annular corrugations on the periphery. The concentric annular corrugations can uniformly convert fluid pressure into axial linear displacement, resulting in a large deformation that meets the large deformation requirements of inductive pressure transmitters and ensures the accuracy of measurement results.

[0023] 3. The test fluids with different pressures are connected to the high and low pressure fluid chambers respectively. The pressure of the high and low pressure sides is received by the left and right elastic isolation diaphragms respectively. The pressure difference between the two sides is converted into the displacement of the magnetic core to achieve accurate differential pressure measurement. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the structure of this utility model;

[0025] Figure 2 To show the cross-sectional view of cavity 5a;

[0026] Figure 3 This is a cross-sectional view of the present invention;

[0027] Figure 4 for Figure 3 A magnified view of a section at point B in the middle;

[0028] Figure 5 To show the sectional views of each chamber;

[0029] Figure 6 This is a schematic diagram of the structure of the pressure-deformed diaphragm 1. Detailed Implementation

[0030] The present invention will be further described below with reference to the embodiments and accompanying drawings.

[0031] like Figure 1 and Figure 2 As shown, an inductive pressure transmitter includes a transmitter body A, the main body of which is composed of a base 5, a left template 6 and a right template 7. The left template 6 and the right template 7 are respectively installed at the left and right ends of the base 5, and the left template 6 and the right template 7 are fixedly connected by four bolts at the four corners. The base 5 has a cavity 5a that runs through it along the thickness direction.

[0032] like Figure 2 As shown, a left elastic isolation diaphragm 8 and a right elastic isolation diaphragm 9 are respectively installed between the left template 6 and the base 5. The left elastic isolation diaphragm 8 and the left template 6 form a low-pressure fluid chamber A4, and the right elastic isolation diaphragm 9 and the right template 7 form a high-pressure fluid chamber A3. The right template 7 has a first opening 7a that connects to the high-pressure fluid chamber A3, and the first opening 7a is used to connect to the high-pressure fluid to be tested. The left template 6 has a second opening 6a that connects to the low-pressure fluid chamber A4, and the second opening 6a is used to connect to the low-pressure fluid to be tested.

[0033] like Figure 3 and Figure 4As shown, displacement detection components and pressure-deformable diaphragms 1 are respectively installed at the left and right ends of the cavity 5a. A transmission chamber A2 is formed between the pressure-deformable diaphragm 1 and the right elastic isolation diaphragm 9, and is filled with a liquid medium. In this embodiment, the liquid medium filled in the subsequent medium-filled chambers A1 and A2 is silicone oil. The stability of silicone oil ensures the accuracy of pressure transmission. A partition 12 is fixedly installed inside the transmission chamber A2, dividing it. A through hole 12a along the thickness direction is opened at its center. The through hole 12a includes a narrow section 12a1 and a wide section 12a2. The narrow section 12a1 faces the right elastic isolation diaphragm 9, and the wide section 12a2 faces the pressure-deformable diaphragm 1. This structure optimizes the efficiency and stability of pressure transmission.

[0034] like Figure 3 and Figure 6 As shown, the pressure-deformable diaphragm 1 includes a centrally planar stress zone 1a and several concentric annular corrugations 1b extending continuously outward from the stress zone 1a. The stress zone 1a is directly opposite the through hole 12a, enabling it to accurately receive the transmitted pressure. The concentric annular corrugations 1b can uniformly convert fluid pressure into axial linear displacement, resulting in a large deformation that meets the large deformation requirements of inductive pressure transmitters, ensuring the accuracy of measurement results. Annular gaskets 11 are provided on both sides of the pressure-deformable diaphragm 1, which are stacked and welded together within the cavity 5a. This installation method reduces the possibility of the pressure-deformable diaphragm 1 being welded through.

[0035] like Figure 4 As shown, the displacement detection assembly includes a cylindrical mounting carrier 13, on which an induction coil 2 is integrated. The induction coil 2 has an inner cavity 2a extending through it along its axial direction. A magnetic core 3 is reciprocally slidably disposed within the inner cavity 2a. One end of the magnetic core 3 is connected to a connecting rod 4 extending outward from the inner cavity 2a. The outer end of the connecting rod 4 is provided with a support step 4a. The outer end face of the support step 4a is fixedly connected to the force-bearing area 1a, which serves as an axial limit to prevent the connecting rod 4 from sliding excessively into the inner cavity 2a under the action of the pressure-deformed diaphragm 1, thus affecting the relative positional accuracy between the magnetic core 3 and the induction coil 2. At the same time, its outer end face is fixedly connected to the force-bearing area 1a to stably transmit the deformation displacement of the pressure-deformed diaphragm 1.

[0036] like Figure 3 and Figure 5As shown, there is a left dielectric chamber A11 between the left elastic isolation diaphragm 8 and the left end of the base 5, and a right dielectric chamber A12 between the pressure-deformed diaphragm 1 and the right end of the base 5. There is a gap between the magnetic core 3 and the inner cavity 2a. The left dielectric chamber A11 and the right dielectric chamber A12 are connected through the inner cavity 2a, which is directly opposite the center of the left elastic isolation diaphragm 8. The base 5 is provided with a channel 5d that runs through it along its axial direction. The channel 5d connects the left dielectric chamber A11 and the right dielectric chamber A12. The dielectric filling chamber A1 is composed of the left dielectric chamber A11, the right dielectric chamber A12, the connected inner cavity 2a, and the channel 5d, and is filled with liquid medium. Channel 5d serves as an auxiliary connecting path between the left medium chamber A11 and the right medium chamber A12, forming a bidirectional flow structure with the inner cavity 2a. When the liquid medium expands and contracts due to temperature changes, the medium can circulate between the left and right chambers through channel 5d and the inner cavity 2a, avoiding the flow obstruction caused by the gap between the magnetic core 3 and the inner cavity 2a due to a single connecting path, and ensuring that the medium pressure can be quickly balanced when the temperature fluctuates. In addition, when the deformed diaphragm 1 moves due to the pressure, channel 5d can help balance the instantaneous pressure difference between the left and right medium chambers caused by the displacement of the magnetic core, reducing the influence of the medium flow resistance on the diaphragm deformation transmission, and further ensuring the stability and accuracy of pressure measurement.

[0037] like Figure 5 As shown, a first groove 5b is formed on the left end face of the base 5, and the bottom shape of the first groove 5b is adapted to the left elastic isolation diaphragm 8; a second groove 12b is formed on the right end face of the partition plate 12, and the bottom shape of the second groove 12b is adapted to the right elastic isolation diaphragm 9. Under overpressure conditions, the first groove 5b and the second groove 12b can provide mechanical restraint to prevent the isolation diaphragm from being excessively deformed and causing permanent damage. The left elastic isolation diaphragm 8 and the right elastic isolation diaphragm 9 have the same structure, both having a planar center and a continuous concentric corrugated periphery. This structure allows the isolation diaphragm to produce stable deformation under pressure.

[0038] like Figure 2 As shown, the base 5 has a mounting hole 5c along its radial direction. An electrical connection socket 10 is installed in the mounting hole 5c. The electrical connection socket 10 can connect to a circuit to convert changes in inductance into a transmittable electrical signal.

[0039] like Figure 3 and Figure 5As shown, the principle of the inductive pressure transmitter is as follows: This transmitter can flexibly adapt to different measurement scenarios. When only a single pressure needs to be measured, only the fluid to be measured can be connected to the high-pressure fluid chamber A3. At this time, the pressure to be measured in the high-pressure fluid chamber A3 acts on the pressure-deformed diaphragm 1 through the right elastic isolation diaphragm 9 and the liquid medium in the transmission chamber A2. The pressure difference causes the pressure-deformed diaphragm 1 to deform, which drives the magnetic core 3 to move in the inner cavity 2a of the induction coil 2, causing the coil inductance to change. The circuit connected through the electrical connection socket 10 converts it into an electrical signal corresponding to the pressure to be measured, thereby realizing the measurement of a single pressure.

[0040] like Figure 3 and Figure 5 As shown, when pressure difference needs to be measured, the high-pressure fluid to be measured is connected to the high-pressure fluid chamber A3, and the low-pressure fluid to be measured is connected to the low-pressure fluid chamber A4. The pressure of the high-pressure fluid to be measured acts on the right elastic isolation diaphragm 9, causing it to deform in the direction of the transmission chamber A2. This pressure is transmitted to the right side of the pressure-deformed diaphragm 1 through the liquid medium in the transmission chamber A2. At the same time, the pressure of the low-pressure fluid to be measured acts on the left elastic isolation diaphragm 8, and is transmitted to the left side of the pressure-deformed diaphragm 1 through the liquid medium in the left medium chamber A11 and the right medium chamber A12. The pressure difference on both sides of the pressure-deformed diaphragm 1 causes it to deform in a specific direction. The force-bearing area 1a in the center drives the connecting rod 4 and the magnetic core 3 to move in the inner cavity 2a of the induction coil 2, causing the inductance of the induction coil 2 to change accordingly with the magnitude of the pressure difference. This change in inductance is processed and converted by the circuit connected to the electrical connection socket 10 to form an electrical signal corresponding to the pressure difference between the high and low pressure fluids to be measured, thereby realizing the accurate measurement of the fluid differential pressure.

[0041] Finally, it should be noted that the above description is merely a preferred embodiment of the present utility model. Those skilled in the art, under the guidance of the present utility model, can make various similar representations without departing from the spirit and claims of the present utility model, and such modifications all fall within the protection scope of the present utility model.

Claims

1. An inductive pressure transmitter, comprising a transmitter body (A), wherein the transmitter body (A) has a sealed and isolated medium-filled chamber (A1) and a high-pressure fluid chamber (A3), a pressure-deformable diaphragm (1) is disposed between the medium-filled chamber (A1) and the high-pressure fluid chamber (A3), the medium-filled chamber (A1) is used to fill a liquid medium, the high-pressure fluid chamber (A3) is used to connect to the fluid to be measured, and the pressure-deformable diaphragm (1) is deformable due to changes in the pressure difference between the medium-filled chamber (A1) and the high-pressure fluid chamber (A3); characterized in that: The medium-filled chamber (A1) is equipped with a displacement detection component, which includes an induction coil (2) and a magnetic core (3) that is movably inserted in the induction coil (2). The magnetic core (3) is connected to the pressure-deformable diaphragm (1).

2. An inductive pressure transmitter according to claim 1, characterized in that: The transmitter body (A) includes a base (5), and a left template (6) and a right template (7) installed at the left and right ends of the base (5). The base (5) has a cavity (5a) that runs through the thickness direction. The displacement detection component and the pressure-deformed diaphragm (1) are respectively installed at the left and right ends of the cavity (5a). The base (5) is equipped with a left elastic isolation diaphragm (8) and a right elastic isolation diaphragm (9) at its left and right ends respectively. A low-pressure fluid chamber (A4) is formed between the left elastic isolation diaphragm (8) and the left template (6). The high-pressure fluid chamber (A3) is formed by the right elastic isolation diaphragm (9) and the right template (7). The low-pressure fluid chamber (A4) is used to connect the fluid to be tested.

3. An inductive pressure transmitter according to claim 2, characterized in that: A transmission chamber (A2) is formed between the pressure-deformable diaphragm (1) and the right elastic isolation diaphragm (9), and the transmission chamber (A2) is filled with a liquid medium.

4. An inductive pressure transmitter according to claim 3, characterized in that: A partition (12) is fixedly provided in the transmission chamber (A2). A through hole (12a) along its thickness direction is provided in the middle of the partition (12). The through hole (12a) includes a narrow section (12a1) and a wide section (12a2). The narrow section (12a1) faces the right elastic isolation diaphragm (9), and the wide section (12a2) faces the pressure-deformed diaphragm (1).

5. An inductive pressure transmitter according to claim 4, characterized in that: The pressure-deformable diaphragm (1) includes a centrally planar stress area (1a) and a plurality of concentric annular corrugations (1b) extending continuously outward from the stress area (1a), wherein the stress area (1a) is directly opposite the through hole (12a).

6. An inductive pressure transmitter according to claim 5, characterized in that: The induction coil (2) has an inner cavity (2a) extending through it along its axial direction. The magnetic core (3) is reciprocally slidably disposed in the inner cavity (2a). One end of the magnetic core (3) is connected to a connecting rod (4) extending outward from the inner cavity (2a). The outer end of the connecting rod (4) is provided with a support step (4a). The outer end face of the support step (4a) is fixedly connected to the force-bearing area (1a).

7. An inductive pressure transmitter according to claim 2, characterized in that: The pressure-deformable diaphragm (1) has annular gaskets (11) on both sides, which are stacked together to form an integral welded in the cavity (5a).

8. An inductive pressure transmitter according to claim 6, characterized in that: The left elastic isolation diaphragm (8) has a left medium chamber (A11) between its left end and the base (5), and the right medium chamber (A12) has a right medium chamber between its right end and the base (5). The left medium chamber (A11) and the right medium chamber (A12) are connected by the inner cavity (2a), which is directly opposite the center of the left elastic isolation diaphragm (8). The base (5) is provided with a channel (5d) that runs through it along its axial direction, and the channel (5d) connects the left medium chamber (A11) and the right medium chamber (A12).

9. An inductive pressure transmitter according to claim 4, characterized in that: The base (5) has a first groove (5b) on its left end face, and the bottom shape of the first groove (5b) is adapted to the left elastic isolation diaphragm (8); The partition (12) has a second groove (12b) on its right end face that is adapted to the bottom of the right elastic isolation diaphragm (9).

10. An inductive pressure transmitter according to claim 2, characterized in that: The base (5) has a mounting hole (5c) along its radial direction, and an electrical connection socket (10) is installed in the mounting hole (5c).

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