A micro differential pressure sensor

Abstract

The present application belongs to the field of uranium enrichment technology, and specifically relates to a micro differential pressure sensor. The micro differential pressure sensor, the comparison chamber seat and the working chamber seat are fixedly connected up and down, and a diaphragm chamber is arranged between the comparison chamber seat and the working chamber seat, dividing the diaphragm chamber into an upper end and a lower end that are not connected to each other and sealed from the outside; a comparison chamber is provided on the comparison chamber seat, and a working chamber is provided on the working chamber, one end of which is respectively connected to the upper end and the lower end of the diaphragm chamber, and the other end is respectively input with atmospheric pressure and the pressure to be measured; a core sleeve is fixed at the center position of the upper end of the diaphragm, and the first coil and the second coil are connected up and down and sleeved on the outside of the core sleeve, and the length of the core sleeve in the first coil is equal to that in the second coil, so as to determine the pressure value of the pressure to be measured according to the inductance of the first coil and the inductance of the second coil. The present application converts the deformation displacement of the diaphragm caused by the pressure change into the linear motion of the core sleeve in the coil, resulting in the change of inductance of the coil, thereby realizing the measurement of the pressure value.

Description

Technical Field

[0001] The present application belongs to the technical field of uranium enrichment, and specifically relates to a micro differential pressure sensor. Background Art

[0002] In my country's nuclear industry production field, nuclear safety factors are of vital importance. Strict requirements are placed on pressure measurement and control instruments used in the process of production. They must have stable and reliable performance, a long service life, and strong corrosion resistance.

[0003] The micro differential pressure sensor is a special sensor in the field of uranium enrichment engineering. It is used to detect the medium pressure in the process system. The linear displacement of the sensor's sensitive element (metal corrugated diaphragm) under force generates an AC voltage pulse signal from the electromagnetic conversion component. After being processed by the internal software and hardware circuits of the digital display instrument, the signal can be displayed locally and transmitted through remote communication. It has good stability and high reliability. Therefore, it plays an important role in the quality control of the uranium enrichment process and the safe and continuous operation of the host.

[0004] At present, there are two main types of instruments suitable for uranium enrichment projects in the domestic and foreign markets: differential pressure instruments and absolute pressure instruments. Among them, differential pressure transmitter instruments have been selected and applied, but the range is too large and the use effect is not ideal. Summary of the invention

[0005] The purpose of the present application is to provide a micro differential pressure sensor to solve the problem of large measuring range and unsatisfactory use effect in the prior art.

[0006] Technical solution to achieve the purpose of this application:

[0007] The embodiment of the present application provides a micro differential pressure sensor, the micro differential pressure sensor comprising: a first coil, a diaphragm, a comparison chamber seat, a working chamber seat, a second coil, a signal socket and a core sleeve;

[0008] The comparison chamber seat and the working chamber seat are fixedly connected up and down, a diaphragm cavity is arranged between the comparison chamber seat and the working chamber seat, two ends of the diaphragm are fixed in the diaphragm cavity, and the diaphragm cavity is divided into an upper end and a lower end which are not communicated with each other and sealed from the outside;

[0009] A comparison chamber is provided on the comparison chamber seat, and a working chamber is provided on the working chamber; one end of the comparison chamber and the working chamber are respectively connected to the upper end and the lower end of the diaphragm chamber, and the other ends are respectively input with atmospheric pressure and the pressure to be measured;

[0010] A core sleeve is fixed at the center of the upper end of the diaphragm, the first coil and the second coil are connected up and down and sleeved on the outside of the core sleeve, and the length of the core sleeve in the first coil is equal to the length of the core sleeve in the second coil;

[0011] The signal socket is connected to the first coil and the second coil, and is used to obtain the inductance of the first coil and the inductance of the second coil, so as to determine the pressure value of the pressure to be measured according to the inductance of the first coil and the inductance of the second coil.

[0012] Optionally, the micro differential pressure sensor further includes: a connecting rod seat and a core sleeve connecting rod;

[0013] A connecting rod seat is welded at the center position of the upper end of the diaphragm, a core sleeve connecting rod is welded on the connecting rod seat, and a core sleeve is welded on the core sleeve connecting rod; the core sleeve is perpendicular to the diaphragm.

[0014] Optionally, the micro differential pressure sensor further includes: a spring connecting rod, a spring and a positive cavity seat;

[0015] A positive cavity seat is fixed at the lower end of the working cavity seat, a groove is arranged at the upper end of the positive cavity seat, and the spring piece is fixed in the groove;

[0016] A through hole connecting the lower end of the diaphragm cavity and the groove is provided on the working chamber seat;

[0017] One end of a spring connecting rod is welded at the center of the lower end of the diaphragm, and the other end of the spring connecting rod is connected to the spring; the spring connecting rod is perpendicular to the diaphragm and coaxial with the core sleeve.

[0018] Optionally, a first sealing gasket is installed between the working chamber seat and the lower plane between the outer diameter and the working diameter of the diaphragm, and between the upper plane between the outer diameter and the working diameter of the diaphragm.

[0019] Optionally, the micro differential pressure sensor further includes: a first winding wheel, a second winding wheel, a first isolation sheet, and a second isolation sheet;

[0020] The first winding wheel is fixed to the upper end of the second winding wheel, the first coil is wound on the first winding wheel, and the second coil is wound on the second winding wheel;

[0021] A second isolation sheet is arranged between the first winding wheel and the second winding wheel, and a first isolation sheet is arranged at the lower end of the second winding wheel; the first winding wheel and the second winding wheel are hollow structures for passing through the core sleeve.

[0022] Optionally, the micro differential pressure sensor further includes: a jacket, a third winding wheel, a third coil, a wheel fixing sleeve and a fixing plate;

[0023] The first coil and the second coil are installed in the outer sleeve and fixed to the upper end of the comparison cavity seat; the upper end of the outer sleeve is fixed with a wire wheel fixing sleeve, and the upper end of the wire wheel fixing sleeve is provided with a fixing sheet;

[0024] The third winding wheel is fixed on the outside of the wheel fixing sleeve, and a third coil connected to the signal socket is wound on the third winding wheel.

[0025] Optionally, the micro differential pressure sensor further includes: a positioning nut and an adjusting nut;

[0026] A vertical core sleeve cavity is arranged at the center of the comparison cavity seat, and the core sleeve is arranged in the core sleeve cavity; a thread is processed on the top of the core sleeve cavity, and a positioning nut is installed;

[0027] A "convex" shaped positioning nut with external threads is installed on the internal threaded portion at the top of the reel fixing sleeve.

[0028] Optionally, the micro differential pressure sensor further includes: a protective jacket;

[0029] The protective outer sleeve is sleeved on the outer sides of the outer sleeve, the positioning nut and the adjusting nut, and the lower end of the protective outer sleeve is fixedly connected with the comparison cavity seat.

[0030] Optionally, the micro differential pressure sensor further includes: a socket fixing plate and a socket base;

[0031] The signal socket is fixedly connected to the socket fixing plate and the socket base by a third screw; the socket fixing plate is fixed to the comparison cavity seat by a second screw;

[0032] A strip groove is processed on the outer sleeve, and the strip groove is directly opposite to the protruding part of the L-shaped socket fixing plate.

[0033] Optionally, the starting end and the terminal end of the first coil, the second coil and the third coil are all welded with a multi-core soft wire, which is connected to the electrical socket as a lead wire;

[0034] The starting end of the first coil is connected to the X1 pin of the electrical socket, the starting end of the second coil is connected to the X2 pin of the electrical socket, and the terminal end of the third coil is connected to the X3 pin of the electrical socket; the terminal end of the first coil, the terminal end of the second coil and the starting end of the third coil are twisted together and connected to the X4 pin of the electrical socket.

[0035] The beneficial technical effects of this application are:

[0036] A micro differential pressure sensor provided in an embodiment of the present application comprises: a first coil, a diaphragm, a comparison cavity seat, a working cavity seat, a second coil, a signal socket and a core sleeve; the comparison cavity seat and the working cavity seat are fixedly connected up and down, a diaphragm cavity is arranged between the comparison cavity seat and the working cavity seat, two ends of the diaphragm are fixed in the diaphragm cavity, and the diaphragm cavity is divided into an upper end and a lower end which are not connected to each other and sealed from the outside; a comparison cavity is provided on the comparison cavity seat, and a working cavity is provided on the working cavity; one end of the comparison cavity and the working cavity are respectively connected to the upper end and the lower end of the diaphragm cavity, and the other end inputs the atmospheric pressure and the pressure to be measured respectively; a core sleeve is fixed at the center position of the upper end of the diaphragm, the first coil and the second coil are connected up and down and sleeved on the outside of the core sleeve, and the length of the core sleeve in the first coil is equal to the length of the core sleeve in the second coil; the signal socket is connected to the first coil and the second coil, and is used to obtain the inductance of the first coil and the inductance of the second coil, so as to determine the pressure value of the pressure to be measured according to the inductance of the first coil and the inductance of the second coil. The embodiment of the present application converts the deformation displacement of the diaphragm caused by pressure changes into the linear motion of the magnetic element in the solenoid coil, causing the coil to produce a change in inductance, and uses an AC bridge circuit to convert the pressure into an electrical signal. The voltage amplitude of the bridge output is proportional to the pressure, thereby realizing the measurement of the pressure value. By replacing different diaphragms, different pressure measurement ranges can be achieved, and the corrosion resistance is strong; the structural design of the sensor is unique, and the structure of the sensor is easy to process, the material is easy to obtain, and the service life is longer; and it has been proven by laboratory performance tests and engineering applications that the performance is reliable and stable. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 A schematic diagram of the structure of a micro differential pressure sensor provided in an embodiment of the present application;

[0038] Figure 2 A schematic diagram of the circuit principle of a micro differential pressure sensor provided in an embodiment of the present application.

[0039] In the figure:

[0040] 1-outer sleeve; 2-first coil; 3-first screw; 4-first winding wheel; 5-first isolating plate; 6-connecting rod seat; 7-first bolt; 8-diaphragm; 9-comparison chamber; 10-comparison chamber seat; 11-first sealing gasket; 12-working chamber seat; 13-working chamber; 14-shrapnel connecting rod; 15-second sealing gasket; 16-shrapnel; 17-positive chamber seat; 18-second bolt; 19-core sleeve connecting rod; 20-second coil; 21-second screw; 22-socket fixing plate; 23-third screw; 24-signal socket; 25-socket base; 26-signal cable; 27-second isolating plate; 28-second winding wheel; 29-third winding wheel; 30-third coil; 31-reel fixing sleeve; 32-core sleeve; 33-protective cover; 34-positioning nut; 35-adjusting nut; 36-third fixing plate; 37-fourth screw. DETAILED DESCRIPTION

[0041] In order to make those skilled in the art better understand the present application, the technical scheme in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the embodiments described below are only a part of the embodiments of the present application, not all. Based on the embodiments recorded in the present application, all other embodiments obtained by those skilled in the art without paying creative work are within the scope of protection of the present application.

[0042] See also Figure 1 , which is a structural schematic diagram of a micro-differential pressure sensor provided in an embodiment of the present application.

[0043] A micro differential pressure sensor provided in an embodiment of the present application includes: a first coil 2, a diaphragm 8, a comparison chamber seat 10, a working chamber seat 12, a second coil 20, a signal socket 24 and a core sleeve 32;

[0044] The comparison chamber seat 10 and the working chamber seat 12 are fixedly connected up and down, and a diaphragm cavity is provided between the comparison chamber seat 10 and the working chamber seat 12. Both ends of the diaphragm 8 are fixed in the diaphragm cavity, and the diaphragm cavity is divided into an upper end and a lower end which are not connected to each other and are sealed from the outside.

[0045] A comparison chamber 9 is provided on the comparison chamber seat 10, and a working chamber 13 is provided on the working chamber 12; one end of the comparison chamber 9 and the working chamber 13 are respectively connected to the upper end and the lower end of the diaphragm chamber, and the other ends are respectively input with atmospheric pressure and the pressure to be measured;

[0046] A core sleeve 32 is fixed at the center of the upper end of the diaphragm 8, the first coil 2 and the second coil 20 are connected up and down and sleeved on the outside of the core sleeve 32, and the length of the core sleeve 32 in the first coil 2 is equal to the length of the core sleeve 32 in the second coil 20;

[0047] The signal socket 24 is connected to the first coil 2 and the second coil 20 for obtaining the inductance of the first coil 2 and the inductance of the second coil 20 so as to determine the pressure value of the pressure to be measured according to the inductance of the first coil 2 and the inductance of the second coil 20 .

[0048] It can be understood that when the comparison chamber 9 and the working chamber 13 are placed in the atmospheric state, there is no pressure difference between the comparison chamber 9 and the working chamber 13, the inductance of the first coil 2 and the inductance of the second coil 20 are the same, the bridge circuit of the sensor is in a balanced state, and the sensor output voltage signal is zero; when the comparison chamber 9 is placed in the atmospheric state, within the measurement range of the sensor, pressure is applied to the working chamber 13, causing the center of the diaphragm 8 to produce a displacement change, resulting in the displacement of the core sleeve 32 component welded on the upper part of the center of the diaphragm 8, deviating from the middle position of the combination of the first coil 2 and the second coil 20 and moving upward or downward, so that the inductance of the first coil 2 and the second coil 20 increases and decreases, the bridge is unbalanced, and the corresponding voltage signal is output. After the voltage signal is processed by the digital display instrument, the pressure value is displayed to achieve the purpose of pressure measurement.

[0049] In some possible implementations of the embodiments of the present application, the micro differential pressure sensor may further include: a connecting rod seat 6 and a core sleeve connecting rod 19;

[0050] A connecting rod seat 6 is welded at the center position of the upper end of the diaphragm 8 , a core sleeve connecting rod 19 is welded on the connecting rod seat 6 , and a core sleeve 32 is welded on the core sleeve connecting rod 19 ; the core sleeve 32 is perpendicular to the diaphragm 8 .

[0051] In one example, the micro differential pressure sensor may further include: a spring connecting rod 14, a spring 17 and a positive cavity seat 17;

[0052] A positive cavity seat 17 is fixed at the lower end of the working cavity seat 12, and a groove is provided at the upper end of the positive cavity seat 17, and the spring piece 17 is fixed in the groove;

[0053] A through hole connecting the lower end of the diaphragm cavity and the groove is provided on the working chamber seat 12;

[0054] One end of a spring link 14 is welded at the center of the lower end of the diaphragm 8 , and the other end of the spring link 14 is connected to the spring 17 ; the spring link 14 is perpendicular to the diaphragm 8 and coaxial with the core sleeve 32 .

[0055] In another example, the first sealing gasket 11 may be installed between the working chamber seat 12 and the lower plane between the outer diameter and the working diameter of the diaphragm 8 and between the upper plane between the outer diameter and the working diameter of the diaphragm 8 .

[0056] In some possible implementations of the embodiments of the present application, the micro differential pressure sensor may further include: a first winding wheel 4, a second winding wheel 28, a first isolation sheet 5 and a second isolation sheet 27;

[0057] The first winding wheel 4 is fixed to the upper end of the second winding wheel 28, the first coil 2 is wound on the first winding wheel 4, and the second coil 20 is wound on the second winding wheel 28;

[0058] A second isolation sheet 27 is provided between the first winding wheel 4 and the second winding wheel 28 , and a first isolation sheet 5 is provided at the lower end of the second winding wheel 28 ; the first winding wheel 4 and the second winding wheel 28 are hollow structures for passing the core sleeve 32 .

[0059] In some possible implementations of the embodiments of the present application, the micro differential pressure sensor may further include: an outer jacket 1, a third winding wheel 29, a third coil 30, a wheel fixing sleeve 31 and a fixing sheet 36;

[0060] The first coil 2 and the second coil 20 are installed in the outer sleeve 1 and fixed to the upper end of the comparison cavity seat 10; the upper end of the outer sleeve 1 is fixed with a wire wheel fixing sleeve 31, and the upper end of the wire wheel fixing sleeve 31 is provided with a fixing sheet 36;

[0061] The third winding wheel 29 is fixed to the outside of the wheel fixing sleeve 31 , and a third coil 30 connected to the signal socket 24 is wound around the third winding wheel 29 .

[0062] In one example, the micro differential pressure sensor further includes: a positioning nut 34 and an adjusting nut 35;

[0063] A vertical core sleeve cavity is provided at the center of the comparison cavity seat 10, and a core sleeve 32 is provided in the core sleeve cavity; a thread is processed on the top of the core sleeve cavity, and a positioning nut 34 is installed;

[0064] A "convex" shaped positioning nut 34 with external threads is installed on the internal threaded portion of the top of the reel fixing sleeve 31.

[0065] In another example, the micro differential pressure sensor further includes: a protective jacket 33;

[0066] The protective sleeve 33 is sleeved on the outer sides of the sleeve 1 , the positioning nut 34 and the adjusting nut 35 , and the lower end thereof is fixedly connected to the comparison cavity seat 10 .

[0067] In some possible implementations of the embodiments of the present application, the micro differential pressure sensor further includes: a socket fixing plate 22 and a socket base 25;

[0068] The signal socket 24 is fixedly connected to the socket fixing plate 22 and the socket base 25 by means of a third screw 23; the socket fixing plate 22 is fixed to the comparison cavity seat 10 by means of a second screw 21;

[0069] A strip groove is processed on the outer sleeve 1, and the strip groove is directly opposite to the protruding part of the L-shaped socket fixing plate 22.

[0070] In one example, the starting and terminal ends of the first coil 2, the second coil 20 and the third coil 30 are all welded with a multi-core soft wire, which is connected to the electrical socket 24 as a lead wire;

[0071] The starting end of the first coil 2 is connected to the X1 pin of the electrical socket 24, the starting end of the second coil 20 is connected to the X2 pin of the electrical socket 24, and the terminal end of the third coil 30 is connected to the X3 pin of the electrical socket 24; the terminal end of the first coil 2, the terminal end of the second coil 20 and the starting end of the third coil 30 are twisted together and connected to the X4 pin of the electrical socket 24.

[0072] like Figure 2 As shown, L1 is the first coil 2, L2 is the second coil 20, and R is the resistance of the third coil 30, which is used for temperature compensation correction. When the comparison chamber 9 is placed in the atmospheric state, within the sensor measurement range, pressure is applied to the working chamber 13, causing the center of the diaphragm 8 to produce displacement changes, resulting in the displacement of the core sleeve 32 component welded on the upper part of the center of the diaphragm 8, deviating from the middle position of the combination of the first coil 2 and the second coil 20 and moving upward or downward, so that the inductance of the first coil 2 and the second coil 20 increases and decreases, the bridge is unbalanced, and the corresponding voltage signal is output. After the voltage signal is processed by the digital display instrument, the pressure value is displayed to achieve the purpose of pressure measurement.

[0073] A micro differential pressure sensor provided in an embodiment of the present application is described in detail below with reference to a specific example.

[0074] In a micro differential pressure sensor provided in an embodiment of the present application, the diaphragm 8 can be a corrugated diaphragm with a connecting rod seat 6 welded to the flat center of the upper part, a core sleeve connecting rod 19 welded to the connecting rod seat 6, a core sleeve connecting rod 19 welded to the core sleeve connecting rod 19, and a core sleeve 32 welded to the core sleeve connecting rod 19. The flat center of the lower part of the corrugated diaphragm 8 is welded to the spring connecting rod 14. When the connecting rod seat 6, the core sleeve connecting rod 19, the core sleeve 32, the spring connecting rod 14 and the flat center of the front and back sides of the corrugated diaphragm 8 are welded, they must be installed on the tooling for welding to ensure the coaxiality of the connecting rod seat 6, the core sleeve connecting rod 19, the core sleeve 32 and the spring connecting rod 14 and the verticality of the connecting rod seat 6, the spring connecting rod 14 and the corrugated diaphragm 8. After the connecting rod seat 6, the core sleeve connecting rod 19, the core sleeve 32, the spring connecting rod 14 and the flat center of the front and back sides of the corrugated diaphragm 8 are welded, a sensitive element unit is formed.

[0075] After the coaxiality and verticality of the sensitive element unit are tested and qualified, it is assembled with the working chamber seat 12. There are 10 threaded holes on the working chamber seat 12. A first sealing gasket 11 is installed between the working chamber seat 12 and the lower plane between the outer diameter and the working diameter of the diaphragm 8. A first sealing gasket 11 of the same specification is installed between the upper plane between the outer diameter and the working diameter of the diaphragm 8. Then, with the help of tooling, the comparison chamber seat 10 is assembled with the diaphragm 8. There are 6 through holes on the comparison chamber seat 10. Six first bolts 7 are used to evenly tighten the periphery of the comparison chamber seat 10, the working chamber seat 12 and the diaphragm 8.

[0076] A "disc-shaped" spring piece 16 is welded on the inner platform at the lower part of the working chamber seat 12, and then the spring piece connecting rod 14 and the spring piece 16 are welded and fixed; a second sealing gasket 15 is installed on the outer platform at the lower part of the working chamber seat 12, and four through holes are processed on the positive chamber seat 17. Four second bolts 18 are used to tighten the positive chamber seat 17 and the working chamber seat 12 in a concave and convex manner to ensure uniform force.

[0077] The second winding wheel 28, the first isolation plate 5, the first winding wheel 4, and the second isolation plate 27 are installed in sequence from the bottom to the top in the hollow cylindrical wire wheel fixing sleeve 31 with grooves on the side for easy lead-out of the wire. The centers of the first isolation plate 15 and the second isolation plate 27 are hollow. The second winding wheel 28 has the same structure as the first winding wheel 4, and the center of the parts is hollow, shaped like The second winding wheel 28 is wound with the second coil 20, and the first winding wheel 4 is wound with the first coil 2. After the assembly of the wire wheel fixing sleeve 31 is completed, it is installed in the outer sleeve 1, and then the fixing plate 36 is installed, and then the third winding wheel 29 is installed. The fixing plate 36 is installed on the upper part of the third winding wheel 29, and the fixing plate 36 and the outer sleeve 1 are evenly tightened with three fourth screws 37.

[0078] The starting end and terminal end of the first coil 2 are marked as ① and ② respectively, the starting end and terminal end of the second coil 20 are marked as ③ and ④ respectively, and the starting end and terminal end of the third coil 30 are marked as ⑤ and ⑥ respectively, all of which are single-core enameled wires. One multi-core soft wire is welded to the end of ①, ②, ③, ④, ⑤, and ⑥, totaling 6 wires, which are connected to the electrical socket 24 of the sensor as lead-out wires. The other end of the soft wire connected to ① is welded to the X1 pin of the electrical socket 24, the other end of the soft wire connected to ③ is welded to the X2 pin of the electrical socket 24, the other end of the soft wire connected to ⑥ is welded to the X3 pin of the electrical socket 24, and the other ends of the three soft wires connected to ②, ④, and ⑤ are twisted together and welded to the X4 pin of the electrical socket 24. There are 4 holes on the electrical socket 24, 4 through holes are processed on the socket base 25, and 4 threaded holes are processed on the L-shaped socket fixing plate 22. The electrical socket 24, the socket base 25 and the L-shaped socket fixing plate 22 are fastened by 4 third screws 23. At this point, the "signal conversion component unit" is fully assembled.

[0079] Then, the "signal conversion component unit" with a cylindrical hole in the center is installed on the comparison cavity seat 10 which has a "mountain" shape in a concave-convex combination manner. There are two threaded holes on the comparison cavity seat 10. The L-shaped socket fixing plate 22 is fastened to the comparison cavity seat 10 with two second screws 21. The conical surface of the outer sleeve 1 part of the "signal conversion component unit" is processed with a strip groove, which has a limiting function, and the strip groove is opposite to the protruding part of the L-shaped socket fixing plate 22. On the comparison cavity seat 10 shaped like a "mountain", the top of the central protruding cylinder is processed with threads, and an adjusting nut 35 is installed. Then, a "convex" positioning nut 34 with external threads is installed on the internal threaded portion of the top of the hollow cylindrical reel fixing sleeve 31, and finally, a protective cover 33 is installed. The lower part of the protective cover 33 is processed with two symmetrical small holes, which is fastened to the comparison cavity seat 10 with two screws. The lower side of the comparison cavity seat 10 is processed with two symmetrical small holes with internal threads. At this point, a complete micro-differential pressure sensor is formed.

[0080] When the comparison chamber 9 and the working chamber 13 of the micro differential pressure sensor are placed in the atmospheric state, there is no pressure difference between the comparison chamber 9 and the working chamber 13, the bridge circuit of the sensor is in a balanced state, and the sensor output voltage signal is zero; when the comparison chamber 9 of the micro differential pressure sensor is placed in the atmospheric state, within the sensor measurement range, pressure is applied to the working chamber 13, causing the center of the diaphragm 8 to produce a displacement change, resulting in the displacement of the connecting rod seat 6, the core sleeve connecting rod 19, and the core sleeve 32 components welded on the upper part of the center of the diaphragm 8, deviating from the middle position of the combination of the first coil 2 and the second coil 20 and moving upward or downward, so that the inductance of the first coil 2 and the second coil 20 increases and decreases, the bridge is unbalanced, and the corresponding voltage signal is output. After the voltage signal is processed by the digital display instrument, the pressure value is displayed to achieve the purpose of pressure measurement.

[0081] The digital display instrument used in conjunction with the micro differential pressure sensor has 7 LED indicator lights on the upper part of the panel. The status is indicated directly above each indicator light, from left to right: operation, communication, range unit (kPa, Pa, Torr optional), (pressure) overload, (pressure) underload; the center of the panel is an LED window that can display numbers or characters; the lower part of the panel has 6 function key touch buttons, from left to right: up key, down key, left shift key, right shift key, set / save (confirm) key, return key.

[0082] The circuit structure of the digital display instrument uses an embedded ARM 32-bit CPU microprocessor chip with a working clock of 168MHz to convert and process the sensor signals and output communication signals and alarm information. In the digital display instrument, in order to facilitate the realization of various operating functions, the program processing software is compiled in C++ language, including: instrument number, range setting, measurement calibration, measurement / calibration format conversion, fast zeroing and other functions, which are displayed in menu mode. By operating the 6 function key touch buttons (up key, down key, left shift key, right shift key, set / save key, return key), the human-computer dialogue function can be easily realized.

[0083] When the differential pressure sensor and the digital display instrument used with it work normally, of the 7 LED indicators on the upper part of the panel of the digital display instrument, only the "Run" indicator flashes, the indicator of the selected range unit (one of kPa, Pa, Torr) is always on, and the other communication, (pressure) overload, (pressure) underload indicators are not on. When the measured pressure exceeds 1% FS of the upper limit of the sensor's measuring range, the "overload" indicator lights up, and at the same time, the central LED window of the panel displays "PPPP"; when the measured pressure is lower than -1% FS of the lower limit of the sensor's measuring range, the "underload" indicator lights up, and at the same time, the central LED window of the panel displays "-PPPP".

[0084] Electrical parameters of digital display instrument:

[0085] The power supply voltage is: (187~242)V, single-phase AC with a frequency of 50Hz;

[0086] Insulation resistance: not less than 20MΩ;

[0087] Power: no more than 12W;

[0088] Output signal: 0~10VDC standard voltage signal, with RS485 communication.

[0089] The power supply voltage for the micro differential pressure sensor is: (15.0±0.5)VAC.

[0090] The overall technical indicators of the digital pressure gauge composed of a micro differential pressure sensor and a digital display instrument are as follows:

[0091] Range and accuracy level:

[0092]

[0093] Value setting range: 0~9999;

[0094] Measurement units: Torr (retain 2 decimal places), kPa (retain 3 decimal places), Pa (retain 1 decimal place).

[0095] Overload condition of micro differential pressure sensor: The micro differential pressure sensor can withstand an overload time of 3 minutes with a pressure not exceeding 0.1MPa from the measuring cavity and the comparison cavity. After the instrument is overloaded and recovers after 10 minutes, the measurement error does not exceed the maximum allowable error within the measurement range.

[0096] The micro differential pressure sensor can also be used for absolute pressure measurement: the comparison chamber and working chamber of the micro differential pressure sensor are evacuated at the same time. When the vacuum pressure in the comparison chamber of the micro differential pressure sensor is maintained in the range of (X~XX)Pa, the absolute pressures of (0~10)Torr, (0~20)Torr, (0~50)Torr, (0~75)Torr, and (0~100)Torr can be relatively measured in the working chamber.

[0097] After testing, the performance of the micro differential pressure sensor provided in the embodiment of the present application can reach the following parameters:

[0098] When the temperature is 10-35℃, within the measurement range of each sensor:

[0099] The accuracy level of 10Torr, 20Torr, 50Torr, 75Torr, and 100Torr sensors is 0.5;

[0100] The 1Torr sensor has an accuracy class of 1.6.

[0101] The micro differential pressure sensor provided in the embodiment of the present application can be used as a special sensor in the field of uranium enrichment engineering. It is used to detect the medium pressure in the process system. The linear displacement of the sensitive element (i.e., the diaphragm) of the sensor is subjected to force, and the electromagnetic conversion component generates an AC voltage pulse signal. After being processed by the internal software and hardware circuits of the digital display instrument, the signal can be displayed locally and transmitted through remote communication, with good stability and high reliability. Therefore, it plays an important role in the quality control of the uranium enrichment process and the safe and continuous operation of the host.

[0102] The micro differential pressure sensor provided in the embodiment of the present application adopts the principle of a solenoid differential inductance sensor, converts the deformation displacement of the diaphragm caused by the pressure change into the linear motion of the magnetic element in the solenoid coil, causing the coil to produce a change in inductance, and uses an AC bridge circuit to convert the pressure into an electrical signal. The voltage amplitude output by the bridge is proportional to the pressure, thereby realizing the measurement of the pressure value. By replacing different diaphragms, different pressure measurement ranges can be achieved, and the corrosion resistance is strong; the structural design of the sensor is unique, and the structure of the sensor is easy to process, the material is easy to obtain, and the service life is longer; and it has been proven by laboratory performance tests and engineering applications that the performance is reliable and stable.

[0103] The present application is described in detail above in conjunction with the accompanying drawings and embodiments, but the present application is not limited to the above embodiments, and various changes can be made within the knowledge of ordinary technicians in the field without departing from the purpose of the present application. Any content not described in detail in the present application can adopt the existing technology.

Claims

1. A micro differential pressure sensor, characterized in that: The micro differential pressure sensor comprises: a first coil (2), a diaphragm (8), a comparison chamber seat (10), a working chamber seat (12), a second coil (20), a signal socket (24) and a core sleeve (32); The comparison chamber seat (10) and the working chamber seat (12) are fixedly connected up and down, a diaphragm cavity is provided between the comparison chamber seat (10) and the working chamber seat (12), two ends of the diaphragm (8) are fixed in the diaphragm cavity, and the diaphragm cavity is divided into an upper end and a lower end which are not connected to each other and are sealed from the outside; A comparison chamber (9) is provided on the comparison chamber seat (10), and a working chamber (13) is provided on the working chamber (12); one end of the comparison chamber (9) and the working chamber (13) are respectively connected to the upper end and the lower end of the diaphragm chamber, and the other ends are respectively input with atmospheric pressure and a pressure to be measured; A core sleeve (32) is fixed at the center position of the upper end of the diaphragm (8); the first coil (2) and the second coil (20) are connected up and down and sleeved on the outside of the core sleeve (32); and the length of the core sleeve (32) in the first coil (2) is equal to the length of the core sleeve (32) in the second coil (20); The signal socket (24) is connected to the first coil (2) and the second coil (20) and is used to obtain the inductance of the first coil (2) and the inductance of the second coil (20), so as to determine the pressure value of the pressure to be measured based on the inductance of the first coil (2) and the inductance of the second coil (20).

2. The micro differential pressure sensor according to claim 1, characterized in that: The micro differential pressure sensor further comprises: a connecting rod seat (6) and a core sleeve connecting rod (19); A connecting rod seat (6) is welded at the center position of the upper end of the diaphragm (8), a core sleeve connecting rod (19) is welded on the connecting rod seat (6), and a core sleeve (32) is welded on the core sleeve connecting rod (19); the core sleeve (32) is perpendicular to the diaphragm (8).

3. The micro differential pressure sensor according to claim 2, characterized in that: The micro differential pressure sensor further comprises: a spring connecting rod (14), a spring (17) and a positive cavity seat (17); A positive cavity seat (17) is fixed at the lower end of the working cavity seat (12), and a groove is provided at the upper end of the positive cavity seat (17), and the spring piece (17) is fixed in the groove; A through hole communicating with the lower end of the diaphragm cavity and the groove is provided on the working chamber seat (12); One end of a spring connecting rod (14) is welded at the center of the lower end of the diaphragm (8), and the other end of the spring connecting rod (14) is connected to the spring (17); the spring connecting rod (14) is perpendicular to the diaphragm (8) and coaxial with the core sleeve (32).

4. The micro differential pressure sensor according to claim 1, characterized in that: A first sealing gasket (11) is installed between the working chamber seat (12) and the lower plane between the outer diameter and the working diameter of the diaphragm (8), and between the upper plane between the outer diameter and the working diameter of the diaphragm (8).

5. The micro differential pressure sensor according to claim 1, characterized in that: The micro differential pressure sensor further comprises: a first winding wheel (4), a second winding wheel (28), a first isolation plate (5) and a second isolation plate (27); The first winding wheel (4) is fixed to the upper end of the second winding wheel (28), the first coil (2) is wound on the first winding wheel (4), and the second coil (20) is wound on the second winding wheel (28); A second isolation sheet (27) is arranged between the first winding wheel (4) and the second winding wheel (28), and a first isolation sheet (5) is arranged at the lower end of the second winding wheel (28); the first winding wheel (4) and the second winding wheel (28) are hollow structures for passing the core sleeve (32).

6. The micro differential pressure sensor according to claim 5, characterized in that: The micro differential pressure sensor further comprises: an outer casing (1), a third winding wheel (29), a third coil (30), a wheel fixing sleeve (31) and a fixing plate (36); The first coil (2) and the second coil (20) are installed in the outer sleeve (1) and fixed to the upper end of the comparison cavity seat (10); a wire wheel fixing sleeve (31) is fixed to the upper end of the outer sleeve (1), and a fixing plate (36) is provided at the upper end of the wire wheel fixing sleeve (31); The third winding wheel (29) is fixed to the outside of the wheel fixing sleeve (31), and a third coil (30) connected to the signal socket (24) is wound on the third winding wheel.

7. The micro differential pressure sensor according to claim 6, characterized in that: The micro differential pressure sensor further comprises: a positioning nut (34) and an adjusting nut (35); A vertical core sleeve cavity is arranged at the center of the comparison cavity seat (10), and a core sleeve (32) is arranged in the core sleeve cavity; a thread is processed on the top of the core sleeve cavity, and a positioning nut (34) is installed; A "convex" shaped positioning nut (34) having external threads is installed at the internal threaded portion at the top of the wire wheel fixing sleeve (31).

8. The micro differential pressure sensor according to claim 7, characterized in that: The micro differential pressure sensor further comprises: a protective jacket (33); The protective outer sleeve (33) is sleeved on the outer sides of the outer sleeve (1), the positioning nut (34) and the adjusting nut (35), and the lower end of the protective outer sleeve (33) is fixedly connected to the comparison cavity seat (10).

9. The micro differential pressure sensor according to claim 6, characterized in that: The micro differential pressure sensor further comprises: a socket fixing plate (22) and a socket base (25); The signal socket (24) is fixedly connected to the socket fixing plate (22) and the socket base (25) by means of a third screw (23); the socket fixing plate (22) is fixed to the comparison cavity seat (10) by means of a second screw (21); A strip groove is processed on the outer sleeve (1), and the strip groove faces the protruding part of the L-shaped socket fixing plate (22).

10. The micro differential pressure sensor according to claim 6, characterized in that: The starting end and the terminal end of the first coil (2), the second coil (20) and the third coil (30) are all welded with a multi-core soft wire, which is connected to the electrical socket (24) as a lead wire; The starting end of the first coil (2) is connected to the X1 pin of the electrical socket (24), the starting end of the second coil (20) is connected to the X2 pin of the electrical socket (24), and the terminal end of the third coil (30) is connected to the X3 pin of the electrical socket (24); the terminal end of the first coil (2), the terminal end of the second coil (20) and the starting end of the third coil (30) are twisted together and connected to the X4 pin of the electrical socket (24).

Images