CN216717672U - Wide-range pressure measuring diaphragm capsule - Google Patents

Abstract

The utility model discloses a wide-range pressure measurement diaphragm box, which comprises two or more than two capacitance type differential pressure sensor modules and two pressure conduction channels, wherein the measurement range of each differential pressure sensor module is sequentially increased, the measurement ranges of the two adjacent differential pressure sensor modules in the measurement ranges are partially overlapped so as to obtain continuous range, two sealed induction cavities separated by a diaphragm are arranged in each differential pressure sensor module, each induction cavity is respectively connected with a pressure leading pipe, the two pressure leading pipes of each differential pressure sensor module are respectively in one-to-one correspondence and communication with the two pressure conduction channels, and the differential pressure sensor modules have an overload protection function. The utility model has the beneficial effects that: the range ratio is greatly improved, and meanwhile, the measurement precision is considered.

Description

Wide-range pressure measuring diaphragm capsule

Technical Field

The utility model relates to a pressure measuring device, in particular to a wide-range pressure measuring diaphragm capsule.

Background

Pressure transmitters are widely used in fluid pressure and flow measurement devices. One type of pressure transmitter has a diaphragm differential pressure sensor as a core sensing element. The diaphragm type differential pressure sensor converts two pressure signals of different positions of fluid into the change of a capacitance signal, and then a detection circuit at the rear end processes the change of the capacitance signal to obtain a differential pressure value of applied pressure.

The diaphragm type differential pressure sensor comprises two disc-shaped diaphragm seats, a measuring diaphragm is arranged between the two diaphragm seats, and the two diaphragm seats are in butt welding connection and clamp the measuring diaphragm. The measuring diaphragm and the two diaphragm seats are respectively provided with an induction cavity for containing silicon oil, the two induction cavities are respectively connected with a pressure leading pipe, and the pressure leading pipe leads external pressure to be measured into two sides of the measuring diaphragm. Due to the fact that the pressures on the two sides are different, the measuring diaphragm deforms towards the side with smaller pressure, and the deformation is reflected as the change of the capacitance signal.

Generally, a diaphragm type differential pressure sensor is arranged in a single pressure measurement module, the performance parameter of the diaphragm type differential pressure sensor is fixed, and the diaphragm type differential pressure sensor has a fixed pressure measurement range. In addition, the measurement range value and the measurement accuracy are difficult to be considered simultaneously, the relative accuracy of the diaphragm type differential pressure sensor with a high measurement range value is low, and when the relative accuracy of the diaphragm type differential pressure sensor is high, the measurement range value is low. However, some application scenarios require a wide measurement range and require high measurement accuracy. Therefore, the sensor module needs to satisfy the requirements of wide range and high precision in view of the overall structure.

SUMMERY OF THE UTILITY MODEL

In view of the above, the present invention provides a wide-range pressure measurement capsule.

The technical scheme is as follows:

the wide-range pressure measurement diaphragm capsule is characterized by comprising two or more capacitive differential pressure sensor modules and two pressure conduction channels, wherein the measurement ranges of the differential pressure sensor modules are sequentially increased, and the measurement ranges of two adjacent differential pressure sensor modules are partially overlapped, so that continuous ranges are obtained;

two sealed induction cavities which are formed by separating a diaphragm are arranged in the differential pressure sensor module, and each induction cavity is connected with a pressure guiding pipe;

the two pressure guiding pipes of each differential pressure sensor module correspond to the two pressure conduction channels one to one respectively, and all the pressure guiding pipes corresponding to the same pressure conduction channel are communicated with the pressure conduction channel;

the differential pressure sensor module has an overload protection function.

As a preferred technical solution, the differential pressure sensor module includes two disc-shaped first membrane seats, a membrane is sandwiched between the two first membrane seats, edges of the two first membrane seats are butt-welded to fix the membrane, and a sealed sensing cavity is formed between each first membrane seat and the membrane;

the different offset deformation amounts of the diaphragms of the differential pressure sensor modules in different measuring ranges under the same differential pressure are different;

the diaphragms of the differential pressure sensor module abut against the corresponding first diaphragm seats when the deformation amount is maximum.

Preferably, the membrane thickness of the differential pressure sensor module in the higher measurement range is greater than the membrane thickness of the differential pressure sensor module in the lower measurement range.

As a preferred technical scheme, each differential pressure sensor module is provided with a static pressure compensation structure corresponding to an induction cavity of the differential pressure sensor module;

the static pressure compensation structure comprises second film seats arranged outside each first film seat, the second film seats are fixedly connected with the outer side edges of the corresponding first film seats in a sealing mode, a pressure stabilizing cavity is formed between each second film seat and the corresponding first film seat in a surrounding mode, and the pressure stabilizing cavity is communicated with the induction cavity located on the same side of the diaphragm.

As a preferred technical scheme, the second membrane seat has the same structure as the first membrane seat;

one side of the first membrane seat, which faces the membrane, is provided with a groove, and the groove on the second membrane seat faces the corresponding outer side face of the first membrane seat;

the pressure guide pipe connected with each induction cavity penetrates through the first membrane seat and the second membrane seat outwards in a sealing mode and is opened in the corresponding pressure stabilizing cavity.

As a preferred technical solution, the first diaphragm seat includes an inner disc made of glass and an outer disc made of metal, the inner side surface of the inner disc is provided with the groove, the inner disc and the outer disc are fused, and the outer side surface and the edge of the inner disc are covered by the outer disc;

the diaphragms are made of metal materials, and the edges of the outer circular discs of the two first diaphragm seats clamp the diaphragms and are connected in a welding mode;

the pressure guiding pipe comprises a straight pipe and a bent pipe;

the straight pipe penetrates through the center of the first membrane seat, two ends of the straight pipe are respectively opened on the bottom surface of the groove of the inner disc and the outer side surface of the outer disc, and the pipe wall of the straight pipe is sealed with the inner disc and the outer disc;

the center of the second membrane seat is provided with the bent pipe in a penetrating way, the inner end of the bent pipe is opened at the bottom surface of the groove of the second membrane seat, the inner end of the bent pipe is opposite to the outer end of the straight pipe, the outer end of the bent pipe outwards penetrates out of the second membrane seat, and the outer wall of the bent pipe is sealed with the second membrane seat.

As a preferred technical scheme, a plated electrode is respectively arranged on the inner side surface of each first film seat, the plated electrode and the corresponding side surface of the diaphragm form a measuring capacitor, the plated electrode of each first film seat is respectively connected with a first signal lead, and the first signal leads respectively penetrate through the first film seats in a sealing manner;

the inner side surface of the second film seat is also provided with a plated electrode, the plated electrode is opposite to the corresponding metal surface on the outer side of the first film seat so as to form a compensation capacitor, the plated electrode on the inner side surface of the second film seat is connected with a second signal lead, and the second signal lead penetrates through the second film seat in a sealing manner.

As a preferred technical solution, the inner end of the second signal lead is connected to the plated film electrode on the inner side surface of the second film holder;

the inner walls of the grooves of the first membrane seat and the second membrane seat are provided with the plated electrodes;

the connection point of the first signal lead or the second signal lead and the corresponding film-coated electrode is close to the edge corresponding to the groove.

Preferably, the inner disc partially extends outwards beyond the outer circumferential surface of the outer wall of the outer disc to form an extension block, and the first signal lead is led out from the inside of the inner disc outwards through the extension block.

Compared with the prior art, the utility model has the beneficial effects that: the differential pressure sensor modules in different measurement ranges are combined, differential pressure signals obtained by the differential pressure sensor modules are used by a measurement circuit selectively, the differential pressure sensor modules have a self-protection function, physical switching is not needed when different pressure measurements are carried out, the range ratio is greatly improved, and meanwhile, the measurement precision is considered.

Drawings

FIG. 1 is a schematic diagram of a pressure measurement device having a wide range pressure measurement capsule;

FIG. 2 is a schematic diagram of a differential pressure sensor module;

FIG. 3 is an exploded view of the pressure measurement device;

FIG. 4 is a schematic view of a first perspective of the pressure measurement device;

FIG. 5 is a sectional view taken along line A-A of FIG. 4;

FIG. 6 is an enlarged view of the portion m of FIG. 5;

FIG. 7 is a cross-sectional view taken along line B-B of FIG. 4;

FIG. 8 is a schematic diagram of a second perspective view of the pressure measurement device;

fig. 9 is a cross-sectional view taken along line C-C of fig. 8.

Detailed Description

The present invention will be further described with reference to the following examples and the accompanying drawings.

Example one

As shown in fig. 1, a wide-range pressure measurement capsule includes two or more capacitive differential pressure sensor modules 100 and two pressure conduction channels, the measurement ranges of the differential pressure sensor modules 100 are sequentially increased, and the measurement ranges of two adjacent differential pressure sensor modules 100 are partially overlapped, so as to obtain continuous ranges.

As shown in fig. 2, two sealed sensing cavities 130 separated by a diaphragm 120 are formed in the differential pressure sensor module 100, and a pressure guiding pipe 160 is connected to each sensing cavity 130. The two pressure guiding pipes 160 of each differential pressure sensor module 100 correspond to the two pressure conduction channels one to one, and all the pressure guiding pipes 160 corresponding to the same pressure conduction channel are communicated with the pressure conduction channel. The differential pressure sensor module 100 has an overload protection function. Each of the differential pressure sensor modules 100 is provided with a static pressure compensation structure corresponding to the sensing cavity 130.

The differential pressure sensor module 100 includes two discoid first membrane seats 110, two the diaphragm 120 that is equipped with the metal material is pressed from both sides between the first membrane seat 110, two the first membrane seat 110 edge butt welding connect in order will the diaphragm 120 is fixed, every first membrane seat 110 with form sealed between the diaphragm 120 the response chamber 130. The amount of deflection of the diaphragm 120 of the differential pressure sensor module 100 at different measurement ranges is different for the same differential pressure. One specific embodiment is to obtain the appropriate deformation ratio by configuring different differential pressure sensor modules 100 with different thicknesses of the diaphragm 120. The membrane 120 thickness of the differential pressure sensor module 100 at the higher measurement range is greater than the membrane 120 thickness of the differential pressure sensor module 100 at the lower measurement range. In addition, diaphragms 120 of different materials can be used, and differential pressure sensor modules 100 having different measurement ranges can be obtained due to the difference in the elastic modulus of each diaphragm 120.

The diaphragm 120 of the differential pressure sensor module 100 deforms to a lower pressure side under the action of a pressure difference, and abuts against the corresponding first diaphragm seat 110 when the deformation amount is maximum, so that overload protection is realized.

The static pressure compensation structure serves to restrain the first diaphragm seat 110 from being deformed outward by the high pressure of the liquid in the sensing chamber 130. The static pressure compensation structure comprises a second film seat 140 arranged outside each first film seat 110, the second film seats 140 are fixedly connected with the outer side edges of the corresponding first film seats 110 in a sealing manner, a pressure stabilizing cavity 150 is defined between each second film seat 140 and the corresponding first film seat 110, and the pressure stabilizing cavity 150 is communicated with the induction cavity 130 on the same side of the diaphragm 120.

The second diaphragm seat 140 has the same structure as the first diaphragm seat 110. The first membrane seat 110 is provided with a groove on one side facing the membrane 120, and the groove on the second membrane seat 140 faces the corresponding outer side of the first membrane seat 110. The pressure introduction tube 160 connected to each sensing cavity 130 is sealed outward and penetrates through the first and second film holders 110 and 140 in sequence, and is opened in the corresponding pressure stabilizing cavity 150.

The inner side surface of each first film holder 110 is provided with a film-coated electrode. The plated electrode on the inner side of each first film holder 110 and the corresponding side of the film 120 opposite to the plated electrode form a first capacitor, i.e. a measurement capacitor. The plated electrode of each first film holder 110 is connected to a first signal lead 170, and the first signal leads 170 respectively penetrate through the first film holder 110 in a sealed manner.

The inner side surface of the second film holder 140 is respectively provided with a plated electrode, the outer side surface of the first film holder 110 is a metal surface, and the plated electrode on the inner side surface of the second film holder 140 and the outer metal surface of the first film holder 110 form a second capacitor, i.e., a compensation capacitor. The coated electrode of the second film holder 140 is connected with a second signal lead 180, and the second signal lead 180 penetrates through the second film holder 140 in a sealing manner.

In this embodiment, the first film seat 110 includes an inner disc 111 made of glass and an outer disc 112 made of metal, the inner side surface of the inner disc 111 is provided with the groove, the inner disc 111 and the outer disc 112 are fused, and the outer side surface and the edge of the inner disc 111 are covered by the outer disc 112. The edges of the outer disks 112 of the two first diaphragm holders 110 hold the diaphragm 120 and are welded.

The inner disc 111 partially extends outward beyond the outer circumferential surface of the outer disc 112 to form an extension block 113, and the first signal lead 170 is led out from the inner disc 111 outward through the extension block 113. In this structure, the first signal lead 170 is embedded in the inner disk 111 and integrally formed when the first film holder 110 is manufactured. The mounting structure of the second signal lead 180 on the second film holder 140 is the same as that of the first signal lead 170. This structure insulates the first signal lead 170 or the second signal lead 180 and the plated electrode from the outer disc 112.

The inner wall of the groove is provided with the film-coated electrode. The connection point of the first signal lead 170 or the second signal lead 180 with the corresponding film-coated electrode is close to the edge of the corresponding groove for facilitating processing.

After the sensor is assembled, all the outer disks 112 made of metal are welded to the diaphragm 120 to form a conductor, all the outer disks 112 and the diaphragm 120 are connected to the same capacitance lead, the capacitance lead and the first signal lead 170 form two leads for measuring capacitance, and the capacitance lead and the second signal lead 180 form two leads for compensating capacitance. All of the first signal lead 170, the second signal lead 180, and the capacitance lead are connected to an external signal processing circuit.

In the presence of a pressure difference, the diaphragm 120 deforms to the pressure-less side, thereby causing the capacitance of the two first capacitances to change in magnitude, and the resulting capacitance change signals are conducted from the first signal leads 170 to external signal processing circuits, respectively, for use in calculating the differential pressure. For each first film seat 110, the hydraulic pressure in the pressure stabilizing cavities 150 on the two sides of the first film seat is always consistent with that in the induction cavity 130, so that the outward deformation of the first film seat 110 in a high-pressure state can be inhibited, and the measurement precision is improved. This is to improve the measurement accuracy from a mechanical point of view.

Since the silicon oil is a medium between the two electrode plates of the second capacitor, the dielectric constant changes when the temperature of the silicon oil changes, so that the capacitance of the compensation capacitor changes. Meanwhile, although the outward deformation of the first diaphragm seat 110 is suppressed, the liquid pressure received by the first diaphragm seat 110 is transmitted to the second diaphragm seat 140 on the same side as the diaphragm 120, so that the second diaphragm seat 140 is slightly deformed outward, and the capacitance of the compensation capacitor is also changed. The formed capacitance change signals are conducted from the second signal leads 180 to an external signal processing circuit, respectively. The signal can be used for detecting parameters such as the temperature and the static pressure of the silicone oil, and can also be substituted into the calculation of the pressure value to be used for correcting the differential pressure value measured based on the measuring capacitor, so that the measuring precision of the sensor is further improved from the electrical angle.

One specific structure of the pressure introduction pipe 160 is that the pressure introduction pipe 160 includes a straight pipe 161 and a bent pipe 162. A straight pipe 161 penetrates through the center of the first diaphragm seat 110, two ends of the straight pipe 161 are respectively opened on the bottom surface of the groove and the outer side surface of the outer disc 112, and the pipe wall of the straight pipe 161 is sealed with the inner disc 111 and the outer disc 112; an elbow pipe 162 penetrates through the center of the second membrane seat 140, the inner end of the elbow pipe 162 is opened on the bottom surface of the groove of the second membrane seat 140, the inner end of the elbow pipe 162 is opposite to the outer end of the straight pipe 161, the outer end of the elbow pipe 162 outwards penetrates through the second membrane seat 140, and the outer wall of the elbow pipe 162 is sealed with the second membrane seat 140.

Example two

As shown in fig. 1, 3, 4 and 8, a pressure measurement device includes a pressure measurement capsule according to a first embodiment that includes two cylindrical differential pressure sensor modules 100. The pressure guide bases 200 are arranged below the two differential pressure sensor modules 100, bosses are arranged on the pressure guide bases 200, and the two differential pressure sensor modules 100 are arranged above the bosses side by side.

As can be seen from fig. 4 to 6, pressure guiding channels 210 are respectively formed on the pressure guiding base 200 corresponding to the two pressure guiding pipes 160, the upper ends of the two pressure guiding channels 210 are open on the upper surface of the boss of the pressure guiding base 200, the lower ends of the two pressure guiding channels 210 are open on a pair of opposite side walls of the pressure guiding base 200, the lower end of the pressure guiding channel 210 is open to form a bell mouth, and each bell mouth is hermetically covered by an elastic isolation diaphragm 220. The pressure introduction passage 210 is filled with silicone oil. The pressure taking seats 300 are respectively installed on the side walls of the pressure leading seats 200 where the two isolation diaphragms 220 are located, pressure taking areas are formed in the pressure taking seats 300, and the pressure taking areas are opposite to the corresponding isolation diaphragms 220.

The upper ports of the two pressure guide channels 210 are respectively located outside the two ends of the two differential pressure sensor modules 100, and a pressure guide pipe socket 230 is respectively arranged at the upper port of each pressure guide channel 210. Two differential pressure sensor modules 100 are respectively arranged at two sides of the connecting line of the two pressure leading pipe sockets 230. After being led out from the corresponding second membrane holders 140, the bent pipes 162 of the pressure pipes 160 of the two differential pressure sensor modules 100 extend horizontally to above the corresponding pressure pipe sockets 230, and then extend downwards to be inserted into the pressure pipe sockets 230 and sealed. As shown in fig. 6, the pressure pipe socket 230 includes a columnar socket body, and two liquid passing holes 231 penetrate through the socket body, and both the two liquid passing holes 231 are parallel to the axial direction of the socket body. The diameter of the upper port of the pressure guiding channel 210 is increased to form a jack, and the pressure guiding pipe socket 230 is fixedly inserted into the jack. The inner ends of the two liquid passing holes 231 are communicated with the insertion hole, and a pressure guiding pipe 160 is inserted from the outer ends of the two liquid passing holes 231 respectively. The pressure guiding pipe 160 may be a metal pipe, and both pressure guiding pipes 160 are soldered and sealed with the pressure guiding pipe socket 230. Thus, two pressure-inducing channels 210 are connected in parallel to the two differential pressure sensor modules 100, and the two pressure-inducing channels 210 constitute the pressure-conducting channels of the pressure-measuring bellows in the first embodiment.

The pressure guiding pipes 160 are hard pipes, and the two pressure guiding pipes 160 support the sensor module 100 to be suspended above the pressure guiding base 200. By the assembling mode, the deformation of a sensor shell caused by the fact that the sensor and the pressure guide seat 200 are installed in a fastening connection mode in the existing design is avoided, and therefore the measurement precision loss caused by the deformation of the first membrane seat 110 due to the assembling stress can be avoided.

As shown in fig. 3, the pressure-inducing seat 200 includes a cylindrical portion 201, an end surface of the cylindrical portion 201 is located on a vertical plane, a sensor mounting block 202 is disposed on a circumferential surface of the cylindrical portion 201, and the sensor mounting block 202 is located above the cylindrical portion 201.

The lower ports of the two pressure guiding channels 210 are respectively opened on two end faces of the cylindrical portion 201. The pressure guiding channel 210 comprises a vertical section and a horizontal section (not shown in the figure), wherein the upper end of the vertical section is opened on the upper surface of the pressure guiding seat 200, the lower end of the vertical section is connected with the horizontal section, one end of the horizontal section is communicated with the lower end of the vertical section, and the other end of the horizontal section extends outwards to the end surface of the cylindrical portion 201. The centers of the two bell mouths are respectively positioned at the centers of the end surfaces of the two cylindrical parts 201, the horizontal sections of the two pressure guiding channels 210 are staggered with each other, and the outer ends of the horizontal sections are opened on the inner wall of the bell mouth and are deviated from the central position.

As shown in fig. 3, 7 to 9, pressure-taking seats 300 are respectively disposed on two end faces of the cylindrical portion 201, the pressure-taking seats 300 are covered on the corresponding isolation diaphragms 220, and the two pressure-taking seats 300 respectively abut against and seal the two end faces of the cylindrical portion 201.

As shown in fig. 7 and 9, a pressure taking hole 310 is opened on a surface of the pressure taking seat 300 facing the isolation diaphragm 220, the pressure taking hole 310 is a blind hole, the pressure taking hole 310 faces the isolation diaphragm 220 to form a pressure taking area, and the pressure taking area is communicated with a pressure taking flow passage 330 opened on the pressure taking seat 300. The pressure taking channel 330 penetrates through the pressure taking seat 300, and the pressure taking channel 330 is vertically intersected and communicated with the assembling hole 320. In this embodiment, the pressure tapping flow channel 330 penetrates the pressure tapping base 300 along the horizontal direction, the pressure tapping branch flow channel 360 is disposed on the pressure tapping base 300 along the vertical direction, the inner end of the pressure tapping branch flow channel 360 is communicated with the pressure tapping hole 310, and the outer end is open on the lower surface of the pressure tapping base 300. Therefore, pressure taking channels in three directions are formed on the pressure taking seat 300, and the pressure taking channels can be flexibly selected to be connected with an external pressure source during measurement.

As shown in fig. 3 and 9, pressure-taking flanges 340 are respectively integrally formed on the side walls of the two ports of the pressure-taking seat 300 corresponding to the pressure-taking runner 330 or the bottom wall of the outer port of the pressure-taking branch runner 360, and the two ports of the pressure-taking runner 330 or the outer port of the pressure-taking branch runner 360 respectively penetrate through the pressure-taking flanges 340.

The pressure taking seat 300 with the opening of the pressure taking hole 310 is provided with an assembling hole 320, the aperture of the assembling hole 320 is larger than that of the pressure taking hole 310, the assembling hole 320 and the pressure taking hole 310 share a hole center line to form a step hole, and the inner wall of the assembling hole 320 is sleeved at the corresponding end part of the cylindrical part 201. The bottom of the assembly hole 320 is provided with a ring groove, the ring groove surrounds the pressure taking hole 310, a sealing ring 321 is arranged in the ring groove, and the bottom of the assembly hole 320 is sealed with the corresponding end face of the cylindrical part 201 by the sealing ring 321.

At least two screw holes 350 are formed through the pressure taking seat 300, the screw holes 350 are arranged in parallel to the assembling holes 320, and all the screw holes 350 are distributed around the assembling holes 320. Bolts are inserted into corresponding screw holes 350 on the two pressure taking bases 300, so that the two pressure taking bases 300 clamp the cylindrical portion 201.

The two pressure taking seats 300 are symmetrically arranged, the assembly structure between the two pressure taking seats and the cylindrical part 201 is simple and compact, and the influences of dimensional tolerances and assembly stress on the pressure conduction channel, such as the deformation of the isolation diaphragm 220 caused by the assembly stress, are reduced to the greatest extent.

The pressure tap 300 is adapted to be connected to a source of pressure to be measured and to transmit the pressure to the corresponding isolation diaphragm 220.

During measurement, the two pressure measuring seats 300 are respectively connected with two points on the fluid flow path, fluid at two different points enters the corresponding pressure measuring areas, and the fluid pressure acts on the corresponding isolation diaphragm 220 and is conducted to the diaphragm 120 through the silicone oil, so that the fluid pressure difference between the two points is measured.

Finally, it should be noted that the above-mentioned description is only a preferred embodiment of the present invention, and those skilled in the art can make various similar representations without departing from the spirit and scope of the present invention.

Claims (9)

1. A wide-range pressure measurement diaphragm capsule is characterized in that: the pressure sensor comprises two or more capacitive differential pressure sensor modules (100) and two pressure conduction channels, the measuring ranges of the differential pressure sensor modules (100) are sequentially increased, and the measuring ranges of two adjacent differential pressure sensor modules (100) are partially overlapped, so that continuous measuring ranges are obtained;

two sealed induction cavities (130) separated by a diaphragm (120) are arranged in the differential pressure sensor module (100), and each induction cavity (130) is connected with a pressure guiding pipe (160);

the two pressure leading pipes (160) of each differential pressure sensor module (100) are respectively in one-to-one correspondence with the two pressure conduction channels, and all the pressure leading pipes (160) corresponding to the same pressure conduction channel are communicated with the pressure conduction channel;

the differential pressure sensor module (100) has an overload protection function.

2. The wide range pressure measurement capsule of claim 1, wherein: the differential pressure sensor module (100) comprises two disc-shaped first membrane seats (110), a membrane (120) is clamped between the two first membrane seats (110), the edges of the two first membrane seats (110) are in butt welding connection to fix the membrane (120), and a sealed induction cavity (130) is formed between each first membrane seat (110) and the membrane (120);

the different measurement ranges of the differential pressure sensor module (100) have different deflection deformation amounts of the diaphragm (120) under the same differential pressure;

the diaphragms (120) of the differential pressure sensor module (100) bear against the respective first diaphragm seats (110) when the deformation is maximal.

3. The wide range pressure measurement capsule of claim 2, wherein: the membrane (120) thickness of the differential pressure sensor module (100) of the higher measuring range is greater than the membrane (120) thickness of the differential pressure sensor module (100) of the lower measuring range.

4. The wide range pressure measurement capsule of claim 2, wherein: each differential pressure sensor module (100) is provided with a static pressure compensation structure corresponding to the induction cavity (130) of the differential pressure sensor module;

the static pressure compensation structure comprises second film bases (140) arranged outside each first film base (110), the second film bases (140) are fixedly connected with the outer side edges of the corresponding first film bases (110) in a sealing mode, a pressure stabilizing cavity (150) is defined between each second film base (140) and the corresponding first film base (110), and the pressure stabilizing cavity (150) is communicated with the induction cavity (130) located on the same side of the diaphragm (120).

5. The wide range pressure measurement capsule of claim 4, wherein: the second membrane seat (140) is identical in structure to the first membrane seat (110);

one side of the first membrane seat (110) facing the membrane (120) is provided with a groove, and the groove on the second membrane seat (140) faces the corresponding outer side face of the first membrane seat (110);

the pressure leading pipe (160) connected with each sensing cavity (130) penetrates through the first membrane seat (110) and the second membrane seat (140) in an outward sealing mode and is opened in the corresponding pressure stabilizing cavity (150).

6. The wide range pressure measurement capsule of claim 5, wherein: the first membrane seat (110) comprises an inner disc (111) made of glass and an outer disc (112) made of metal, the inner side surface of the inner disc (111) is provided with the groove, the inner disc (111) and the outer disc (112) are fused, and the outer side surface and the edge of the inner disc (111) are covered by the outer disc (112);

the diaphragms (120) are made of metal materials, and the edges of the outer disks (112) of the two first diaphragm seats (110) clamp the diaphragms (120) and are connected in a welding mode;

the pressure guiding pipe (160) comprises a straight pipe (161) and a bent pipe (162);

the straight pipe (161) penetrates through the center of the first membrane seat (110), two ends of the straight pipe (161) are respectively opened on the bottom surface of the groove of the inner disc (111) and the outer side surface of the outer disc (112), and the pipe wall of the straight pipe (161) is sealed with the inner disc (111) and the outer disc (112);

the bent pipe (162) penetrates through the center of the second film seat (140), the inner end of the bent pipe (162) is opened on the bottom surface of the groove of the second film seat (140), the inner end of the bent pipe (162) is opposite to the outer end of the straight pipe (161), the outer end of the bent pipe (162) penetrates out of the second film seat (140), and the outer wall of the bent pipe (162) is sealed with the second film seat (140).

7. The wide range pressure measurement capsule of claim 6, wherein: the inner side surface of each first membrane seat (110) is respectively provided with a plated electrode, the plated electrode and the corresponding side surface of the membrane (120) form a measuring capacitor, the plated electrode of each first membrane seat (110) is respectively connected with a first signal lead (170), and the first signal leads (170) respectively penetrate through the first membrane seats (110) in a sealing manner;

the inner side surface of the second film seat (140) is also provided with a plated electrode, the plated electrode is opposite to the corresponding metal surface on the outer side of the first film seat (110) to form a compensation capacitor, the plated electrode on the inner side surface of the second film seat (140) is connected with a second signal lead (180), and the second signal lead (180) penetrates out of the second film seat (140) in a sealing mode.

8. The wide range pressure measurement capsule of claim 7, wherein: the inner end of the second signal lead (180) is connected to the plated film electrode on the inner side surface of the second film seat (140);

the inner walls of the grooves of the first membrane seat (110) and the second membrane seat (140) are provided with the plated electrodes;

the connection point of the first signal lead (170) or the second signal lead (180) and the corresponding film-coated electrode is close to the edge of the corresponding groove.

9. The wide range pressure measurement capsule of claim 8, wherein: the inner disc (111) partially extends outwards beyond the circumferential surface of the outer wall of the outer disc (112) to form an extension block (113), and the first signal lead (170) is led out from the inner disc (111) outwards through the extension block (113).

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