CN209802563U

CN209802563U - Embedded pressure sensor

Info

Publication number: CN209802563U
Application number: CN201920487809.XU
Authority: CN
Inventors: 崔启洲
Original assignee: Nanjing Logistics Electronic Technology Co Ltd
Current assignee: Nanjing Logistics Electronic Technology Co Ltd
Priority date: 2019-04-11
Filing date: 2019-04-11
Publication date: 2019-12-17
Anticipated expiration: 2029-04-11

Abstract

The utility model relates to an bury formula pressure sensor, which comprises a housin, the fluid probe, the raceway, silicon piezoresistive pressure core, the installation supporting part, the PCB circuit board, wireless transmitting antenna, the antenna installation department, be equipped with the holding tank side by side around two in the casing, in the holding tank of front portion was located to the fluid probe, silicon piezoresistive pressure core, installation supporting part and PCB circuit board are located in the holding tank at rear portion, silicon piezoresistive pressure core and PCB circuit board are installed in the both sides of installation supporting part, PCB circuit board is connected to silicon piezoresistive pressure core, two holding tanks are linked together through the raceway, fluid inlet has been seted up to the preceding tip of casing, holding tank before fluid inlet passes through the raceway intercommunication, the antenna installation department sets up in the back tip of casing, the antenna installation department is arranged in to wireless transmitting antenna, wireless transmitting antenna passes through the wire. The sensor has the advantages of high sensitivity, quick response, good reliability and high precision.

Description

Embedded pressure sensor

Technical Field

The utility model discloses pressure sensor technical field especially relates to an bury formula pressure sensor who buries in soil, rock.

Background

At present, pressure sensor wide application is in the pressure measurement of liquid or gaseous medium, and because current pressure sensor's structural constraint, just can't directly measure to the fluid pressure in the solid medium (like soil, rock), if directly adopt the pressure sensor of current structure to carry out the fluid pressure measurement of solid medium, the solid medium will direct contact pressure sensor's pressure diaphragm, can cause permanent destruction to pressure diaphragm, and then leads to pressure sensor inefficacy.

Disclosure of Invention

An object of the utility model is to provide a simple structure is reliable, use simple to operate, pressure measurement performance is good, data wireless transmission's bury formula pressure sensor. The real-time automatic monitoring is realized,

In order to achieve the above object, the technical solution adopted by the present invention is an embedded pressure sensor, comprising a waterproof housing, a fluid probe, a water pipe, a silicon piezoresistive pressure core, an installation support part, a PCB, a wireless transmitting antenna, and an antenna installation part, wherein two holding tanks are arranged in the waterproof housing side by side in front and back, the fluid probe is arranged in the holding tank at the front part, the silicon piezoresistive pressure core, the installation support part, and the PCB are arranged in the holding tank at the back part, the silicon piezoresistive pressure core and the PCB are respectively installed at two sides of the installation support part, the silicon piezoresistive pressure core is electrically connected with the PCB, the front and back holding tanks are communicated with each other through the water pipe, a fluid inlet is arranged at the front end part of the waterproof housing, the fluid inlet is communicated with the front holding tank through the water pipe, the antenna installation part is arranged, and a wire hole is arranged between the rear accommodating groove and the antenna installation part, and the wireless transmitting antenna is connected with the PCB circuit board through a wire.

As an improvement of the utility model, the fluid probe is full of whole front holding tank inner chamber, and the front end of fluid probe contacts with the raceway tip of intercommunication fluid entry, and the rear end of fluid probe contacts with the raceway tip of intercommunication rear holding tank, and the fluid probe includes porous argil piece and stainless steel filter screen, and the stainless steel filter screen wraps up in the periphery of porous argil piece.

as an improvement of the utility model, the silicon piezoresistive pressure core comprises a stainless steel shell, a pressure chamber, a corrugated isolation diaphragm, a silicon pressure-sensitive chip, a ceramic ring, silicon oil, a sealing ring and a stainless steel glass sintered body, the corrugated isolation diaphragm is welded at the front end of the stainless steel shell, the stainless steel glass sintered body is arranged at the rear end of the stainless steel shell, a pressure chamber penetrating through the stainless steel shell is arranged in the stainless steel shell, the corrugated isolation diaphragm and the stainless steel glass sintered body are positioned at two ends of the pressure chamber, silicone oil is filled in the pressure chamber, the silicon pressure-sensitive chip is arranged in the pressure chamber and is adhered to the stainless steel glass sintered body through the silica gel, the ceramic ring is sleeved on the outer layer of the silicon pressure-sensitive chip, the stainless steel glass sintered body is provided with a wiring terminal, and the sealing ring is sleeved on the welding connection part between the corrugated isolation diaphragm and the stainless steel shell.

As an improvement of the utility model, be equipped with rechargeable battery package, temperature compensation module, signal amplification module, microcontroller on the PCB circuit board, silicon piezoresistive pressure core passes through wire connection temperature compensation module, and temperature compensation module is connected with signal amplification module, and microcontroller's AD conversion passageway is connected to signal amplification module, and microcontroller includes CPU and RF radio frequency emission module, and rechargeable battery package connection temperature compensation module, signal amplification module, microcontroller provide the power for the PCB circuit board.

As an improvement of the utility model, the waterproof shell is made of Ha's C-276 alloy, has good mechanical strength, acid and alkali corrosion resistance and thermal stability, and can form good protection effect on devices inside the shell.

As an improvement of the utility model, wireless transmitting antenna adopts 433MHz gilding spring antenna, and the structure of this antenna is ingenious, simple to operate, and the stable performance has fine anti-vibration and ageing resistance.

As an improvement of the present invention, the microcontroller adopts the ultra-low power consumption of TI company which is less than 1GHz RF device CC1310, and the microcontroller has very low active RF and MCU currents.

As an improvement of the utility model, a solar cell panel is arranged at the outer end part of the antenna installation part and is connected with the rechargeable battery pack through a wire.

Compared with the prior art, the utility model discloses an overall structure design benefit, rational in infrastructure stability, compact, installation convenient to use, measuring sensitivity is high, be applicable to the fluid pressure who measures with stainless steel compatible solid medium, the silicon piezoresistive pressure core structure that uses can effectively ensure that measured data's repeatability and hysteresis error are little, simultaneously because the silicon single crystal rigidity itself that silicon pressure sensitive chip adopted is big, its deformation diminishes, good linearity has effectively been guaranteed for the sensor has higher comprehensive static accuracy. In addition, the working elastic deformation of the corrugated isolation diaphragm used on the silicon piezoresistive pressure core body is reduced to the magnitude order of micro strain, and the maximum displacement of the elastic film is in the magnitude order of submicron, so that the pressure sensor has no abrasion, fatigue and aging, and the service life of the pressure sensor is effectively ensured to be more than 107 pressure cycles. In addition, the sensor uses a data transmission mode of transmitting measurement data wirelessly by RF radio frequency, and the sensor can be self-powered by the solar cell panel, so that the use and installation convenience of the sensor are greatly improved.

Drawings

Fig. 1 is a schematic structural diagram of an embedded pressure sensor according to an embodiment of the present invention.

In the figure: the solar energy water-cooling system comprises a waterproof shell 1, a fluid probe 2, a silicon piezoresistive pressure core 3, a PCB 4, an antenna mounting part 5, a water pipe 6, a mounting support part 7, a fluid inlet 8, a sealing ring 9, a stainless steel glass sintered body 10-316L and a solar panel 11.

Detailed Description

For the purposes of promoting an understanding and appreciation of the invention, the invention will be further described and illustrated in connection with the accompanying drawings.

As shown in fig. 1, an embedded pressure sensor according to an embodiment of the present invention includes a waterproof housing 1, a fluid probe 2, a water pipe, a silicon piezoresistive pressure core 3, an installation support portion 7, a PCB 4, a wireless transmitting antenna, and an antenna installation portion 5, two front and back parallel accommodation grooves are provided in the waterproof housing 1, the fluid probe 2 is disposed in the front accommodation groove, the fluid probe 2 is used for detecting and adsorbing fluid in a solid medium to measure fluid pressure of the silicon piezoresistive pressure core 3 at the rear stage, the silicon piezoresistive pressure core 3, the installation support portion 7, and the PCB 4 are disposed in the rear accommodation groove, the silicon piezoresistive pressure core 3 and the PCB 4 are respectively installed at two sides of the installation support portion 7, the installation support portion 7 fixedly supports the silicon piezoresistive pressure core 3 and the PCB 4, the silicon piezoresistive pressure core 3 is electrically connected to the PCB 4, the silicon piezoresistive pressure core 3 can convert the sensed fluid pressure signal into an electric signal and send the electric signal to the PCB 4 for preprocessing. The front and back holding tank is linked together through the raceway, the fluid that fluid probe 2 adsorbs passes through the raceway and carries to silicon piezoresistive pressure core 3's pressure interface, fluid inlet 8 has been seted up to waterproof casing 1's preceding tip, fluid inlet 8 passes through holding tank before 6 intercommunications of raceway, fluid inlet 8 is the direct contact portion of solid medium and sensor, the front end of holding tank before containing fluidic solid medium passes through fluid inlet 8 and 6 entering of raceway, antenna installation department 5 sets up in waterproof casing 1's rear end portion, wireless transmitting antenna sets up in antenna installation department 5, be equipped with the wire guide between rear holding tank and the antenna installation department 5, wireless transmitting antenna passes through the wire and connects PCB circuit board 4, the data after PCB circuit board 4 handles are launched out through wireless transmitting antenna.

Specifically, the fluid probe 2 is filled in the inner cavity of the whole front accommodating groove to ensure the detection accuracy of the fluid pressure in the solid medium as much as possible, the front end of the fluid probe 2 is in contact with the end part of a water pipe communicated with the fluid inlet 8, the rear end of the fluid probe 2 is in contact with the end part of the water pipe communicated with the rear accommodating groove, the fluid probe 2 comprises a porous pottery clay block and a 316L stainless steel filter screen, and the 316L stainless steel filter screen is wrapped on the periphery of the porous pottery clay block. The porous pottery clay block is mainly prepared from silt-sandy clay consisting of hydromica, kaolinite, montmorillonite, quartz and feldspar, has good water absorbability and fluid adsorbability, and also has good weather resistance and corrosion resistance, and meanwhile, the porous pottery clay block is limited by a 316L stainless steel filter screen to prevent the porous pottery clay block from swelling and scattering after absorbing water, and on the other hand, the 316L stainless steel filter screen can effectively isolate a solid medium from the porous pottery clay block to prevent the porous pottery clay block from being polluted to reduce the use performance of the porous pottery clay block.

Further, the silicon piezoresistive pressure core 3 comprises a 316L stainless steel shell, a pressure chamber, a corrugated isolation diaphragm, a silicon pressure sensitive chip, a ceramic ring, silicon oil, a sealing ring 9, and a 316L stainless steel glass sintered body 10, wherein the corrugated isolation diaphragm is welded at the front end of the 316L stainless steel shell, the corrugated isolation diaphragm is used as a pressure interface of the silicon piezoresistive pressure core 3 and can sense the pressure of fluid conveyed in a water conveying pipe, preferably, the corrugated isolation diaphragm is made of a tantalum sheet with good flexibility, the 316L stainless steel glass sintered body 10 is arranged at the rear end of the 316L stainless steel shell, the 316L stainless steel shell is internally provided with the pressure chamber penetrating through the 316L stainless steel shell, the corrugated isolation diaphragm and the 316L stainless steel glass sintered body 10 are positioned at two ends of the pressure chamber, the silicon oil is filled in the pressure chamber, the silicon pressure sensitive chip is arranged in the pressure chamber, and the silicon pressure sensitive chip is pasted on the 316L stainless steel glass sintered body 10 through silica gel, the ceramic ring is sleeved on the outer layer of the silicon pressure sensitive chip, preferably, the ceramic ring is formed by adopting alumina 95 ceramic compression molding, the ceramic ring is used for supporting and protecting the silicon pressure sensitive chip so as to reduce the amount of silicon oil filled into the pressure chamber, thereby reducing the influence of the silicon oil on the silicon pressure sensitive chip, the 316L stainless steel glass sintered body 10 is provided with a wiring terminal, and the sealing ring 9 is sleeved on the welding connection part between the corrugated isolation diaphragm and the 316L stainless steel shell. Preferably, the sealing ring 9 is a fluorinated rubber sealing ring 9, so that the assembly is convenient, and the reliable sealing to the pressure can be realized. The silicon piezoresistive pressure core body 3 of the embodiment encapsulates the silicon pressure sensitive chip in the 316L stainless steel shell, when in use, the pressure of fluid is firstly transmitted to the silicon oil in the pressure chamber through the corrugated isolation diaphragm and is transmitted to the silicon pressure sensitive chip through the micro-motion of the silicon oil, so that the silicon pressure sensitive chip is not in direct contact with the fluid in the solid medium, and the whole sensor forms an all-solid-state structure for measuring the fluid pressure and is suitable for the severe environment of the measured medium.

Furthermore, the PCB circuit board 4 is provided with a rechargeable battery pack, a temperature compensation module, a signal amplification module and a microcontroller, the silicon piezoresistive pressure core 3 is connected with the temperature compensation module through a wire, the temperature compensation module is used for performing precise compensation on the temperature characteristic of the silicon piezoresistive pressure core 3, the temperature compensation module is connected with the signal amplification module, the signal amplification module is connected with an AD conversion channel of the microcontroller, the signal amplification module is used for amplifying the electric signal subjected to the temperature compensation processing and transmitting the electric signal into the microcontroller for wireless transmission processing after the electric signal is converted into a digital signal through AD. The microcontroller comprises a CPU and an RF (radio frequency) transmitting module, the rechargeable battery pack is connected with the temperature compensation module, the signal amplification module and the microcontroller, and the rechargeable battery pack provides power for the PCB (printed circuit board) 4. The electric quantity of the rechargeable battery pack can be supplemented by charging, so that the stable and reliable work of the sensor is ensured.

Furthermore, the microcontroller adopts an ultra-low power consumption lower than 1GHz radio frequency device CC1310 of TI company, has extremely low active RF radio frequency and MCU current, and low power consumption mode current consumption, and can effectively ensure the service life of the rechargeable battery pack. Meanwhile, the MCU and the RF transmitting module are integrated on the same chip, so that the size of the PCB can be effectively reduced, and the installation is convenient.

Furthermore, the wireless transmitting antenna adopts a 433MHz gold-plated spring antenna, and the antenna has the advantages of good standing-wave ratio performance, small overall dimension, ingenious structure, convenience in installation, stable performance and good vibration and aging resistance. The inside antenna that is equipped with of antenna mounting portion 5 holds the chamber, locates the antenna with wireless transmitting antenna earlier and holds the intracavity, then with 5 welded connection of antenna mounting portion in waterproof casing 1's rear end portion.

Furthermore, the waterproof shell 1 is made of Hastelloy C-276 alloy, has good mechanical strength, acid and alkali corrosion resistance and thermal stability, can well protect devices in the shell, and can effectively guarantee the detection accuracy and the service life of the sensor.

Further, in order to realize a self-power function of the sensor, a solar panel 11 is provided at an outer end portion of the antenna mounting portion 5, and the solar panel 11 is connected to a rechargeable battery pack through a lead wire. When the sensor is used, the solar cell panel 11 is exposed on the outer surface of the solid medium, so that the solar cell panel 11 absorbs solar energy to generate electricity to charge the rechargeable battery pack.

The utility model provides an bury formula pressure sensor's overall structure design benefit, measuring sensitivity is high, response time is not more than 2ms, be applicable to the fluid pressure who measures with stainless steel compatible solid medium, the silicon piezoresistive pressure core structure that uses can effectively ensure that measured data's non-repeatability and hysteresis error are little, simultaneously because the silicon single crystal rigidity itself that silicon pressure sensitive chip adopted is big, its deformation diminishes, good linearity has effectively been guaranteed, make the sensor have higher comprehensive static accuracy. In addition, the working elastic deformation of the corrugated isolation diaphragm used on the silicon piezoresistive pressure core body is reduced to the magnitude order of micro strain, and the maximum displacement of the elastic film is in the magnitude order of submicron, so that the pressure sensor has no abrasion, fatigue and aging, and the service life of the pressure sensor is effectively ensured to be more than 107 pressure cycles. In addition, the sensor uses a data transmission mode of transmitting measurement data wirelessly by RF radio frequency, and the sensor can be self-powered by the solar cell panel, so that the use and installation convenience of the sensor are greatly improved.

The technical means disclosed by the scheme of the present invention is not limited to the technical means disclosed by the above embodiments, but also includes the technical scheme formed by the arbitrary combination of the above technical features. It should be noted that, for those skilled in the art, without departing from the principle of the present invention, several improvements and modifications can be made, and these improvements and modifications are also considered as the protection scope of the present invention.

Claims

1. An embedded pressure sensor, comprising: comprises a waterproof shell, a fluid probe, a water pipe, a silicon piezoresistive pressure core body and an installation supporting part, PCB circuit board, wireless transmitting antenna, the antenna installation department, be equipped with the holding tank side by side around two in the waterproof casing, fluid probe locates in the anterior holding tank, silicon piezoresistive pressure core, installation supporting part and PCB circuit board are located in the holding tank at rear portion, silicon piezoresistive pressure core and PCB circuit board are installed respectively in the both sides of installation supporting part, PCB circuit board is connected to silicon piezoresistive pressure core electricity, the holding tank is linked together through the raceway around, fluid inlet has been seted up to the preceding tip of waterproof casing, fluid inlet passes through holding tank before the raceway intercommunication, the antenna installation department sets up in the back tip of waterproof casing, wireless transmitting antenna sets up in the antenna installation department, be equipped with the wire guide between back holding tank and the antenna installation department, wireless transmitting antenna passes through the wire and connects the PCB.

2. The embedded pressure sensor of claim 1, wherein the fluid probe fills the entire interior cavity of the front receiving tank, the front end of the fluid probe contacts the end of the water pipe connected to the fluid inlet, the rear end of the fluid probe contacts the end of the water pipe connected to the rear receiving tank, the fluid probe comprises a porous clay block and a stainless steel filter, and the stainless steel filter is wrapped around the porous clay block.

3. The embedded pressure sensor of claim 1 or 2, wherein the silicon piezoresistive pressure core comprises a stainless steel casing, a pressure chamber, a corrugated isolation diaphragm, a silicon pressure sensitive chip, a ceramic ring, silicon oil, a sealing ring, and a stainless steel glass sintered body, the corrugated isolation diaphragm is welded to the front end of the stainless steel casing, the stainless steel glass sintered body is disposed at the rear end of the stainless steel casing, a pressure chamber penetrating through the stainless steel shell is arranged in the stainless steel shell, the corrugated isolation diaphragm and the stainless steel glass sintered body are positioned at two ends of the pressure chamber, silicone oil is filled in the pressure chamber, the silicon pressure-sensitive chip is arranged in the pressure chamber and is adhered to the stainless steel glass sintered body through the silica gel, the ceramic ring is sleeved on the outer layer of the silicon pressure-sensitive chip, the stainless steel glass sintered body is provided with a wiring terminal, and the sealing ring is sleeved on the welding connection part between the corrugated isolation diaphragm and the stainless steel shell.

4. The embedded pressure sensor of claim 3, wherein the PCB is provided with a rechargeable battery pack, a temperature compensation module, a signal amplification module, and a microcontroller, the silicon piezoresistive pressure core is connected to the temperature compensation module through a wire, the temperature compensation module is connected to the signal amplification module, the signal amplification module is connected to an AD conversion channel of the microcontroller, the microcontroller comprises a CPU and an RF transmission module, and the rechargeable battery pack is connected to the temperature compensation module, the signal amplification module, and the microcontroller to provide power for the PCB.

5. The embedded pressure sensor of claim 4, wherein the microcontroller employs a radio frequency device CC1310 by TI.

6. The embedded pressure sensor of claim 5, wherein the wireless transmitting antenna is a 433MHz gold plated spring antenna.

7. The embedded pressure sensor of claim 6, wherein the waterproof housing is fabricated from harderian C-276 alloy.

8. The embedded pressure sensor of claim 7, wherein a solar panel is provided at an outer end of the antenna mounting portion, and the solar panel is connected to the rechargeable battery pack through a wire.