CN115979497B

CN115979497B - Small-diameter high-pressure sensor, manufacturing method thereof and sensor diameter reduction method

Info

Publication number: CN115979497B
Application number: CN202310044888.8A
Authority: CN
Inventors: 邬若军; 付延彬; 聂小龙; 袁学超; 黄孟孟; 万正文
Original assignee: Shenzhen Ampron Technology Corp
Current assignee: Shenzhen Ampron Technology Corp
Priority date: 2023-01-30
Filing date: 2023-01-30
Publication date: 2023-10-27
Anticipated expiration: 2043-01-30
Also published as: CN115979497A

Abstract

The invention relates to the field of high pressure sensors used in automobile braking, in particular to a small-diameter high pressure sensor with small size, a manufacturing method and a diameter reducing method of the high pressure sensor. The small diameter high pressure sensor of the present invention comprises: a pressure sensing body including a pressure receiving surface; the pressure sensing main body is provided with a fluid hole, and one end of the fluid hole penetrates through the connecting end; a pressure sensing film is formed between the other end of the fluid hole and the pressure receiving surface; the strain gauge is arranged on the pressure sensing film; the shell is fixedly connected with one end of the shell; a spring seat fixedly connected with the shell; a snake pin needle fixedly mounted on the spring seat; a first circuit board mounted in the housing at a horizontal angle, the first circuit board being between the strain gauge and the spring seat; the first circuit board is electrically connected with the strain gauge and the snake pin needle respectively.

Description

Small-diameter high-pressure sensor, manufacturing method thereof and sensor diameter reduction method

Technical Field

The invention relates to the field of high pressure sensors used in automobile braking, in particular to a small-diameter high pressure sensor with small size, a manufacturing method and a diameter reducing method of the high pressure sensor.

Background

In the braking system of a car, pressure sensors are used. The automobile brake pressure sensor has very large effect, is an indispensable component in a brake system, is frequently applied to a safety control system, and is mainly aimed at the field of safety management systems of air compressors and relates to driving safety.

The high pressure sensor is mainly applied to an automobile brake system in the automobile industry at present and is used for generating a signal output by measuring pressure; the pressure sensor can detect the pressure of the accumulator, output a closing or opening signal of the oil pump and alarm the abnormality of the oil pressure; the semiconductor strain gauge is arranged in the semiconductor strain gauge, and the characteristic that the resistance of the strain gauge changes when the shape of the strain gauge changes is utilized; in addition, a metal diaphragm is also arranged, the pressure change is detected through a metal diaphragm strain gauge, and the pressure change is converted into an electric signal and then is output outwards.

Further, an anti-lock brake system in an automobile is known as a system in which wheels are not locked during braking. It is conceivable that the front wheels will not lock up after the driver has depressed the brake pedal quickly during an emergency braking, and steering capability still exists, so that measures can be taken completely to avoid the danger in front during braking. If the rear wheel is not locked, sideslip and tail flick will not occur, and the control of the vehicle body is still in the hands of the driver.

The function of the device is mainly to provide a steering model for a computer, and the computer can automatically increase the idle speed to prevent the steering flameout after receiving a steering signal.

The pressure sensor on the market at present is developed in the industry for many years, and has undergone multiple technological evolution, wherein the Chinese patent publication number is: CN104736985B, patent name: the pressure sensor adopts the technical scheme that the pressure sensor is the latest in the prior art and is most widely applied to the market, and is uniformly accepted by automobile manufacturers in all countries of the world including China. However, as it has been found in long-term use, this patent, and including other pressure sensors currently available, presents at least the following problems (the deficiencies of the current high pressure sensors are not exhaustive due to limited space, and therefore the following list of large deficiencies):

1. the existing pressure sensor applied to an automobile brake system is small in product installation space, and is a high-pressure product, so that under the condition that the space between the transverse space and the longitudinal space is limited, a sensing part of the product is formed by welding an MIM Port and a Port, the product is continuously impacted by high pressure and high temperature in the use process, the structural stability of the product in the prior art is insufficient, weld cracks can occur under long-term impact, the problems of leakage or insufficient tolerance in the use process and the like are easily caused, the internal structure of the product is loose, binding wires are broken, the product is invalid, and the service life of the product is not long; this problem is a relatively hidden problem and is difficult to find at present, and even if leakage or failure occurs after the product is used for a certain period of time, the product is generally considered to be naturally aged in the industry, so that the problem is ignored in the industry in daily life.

2. In the prior art, there are at least two problems with component terminals:

(1) The novel plastic is made of metal sheets through bending, and has the advantages of high production cost, long time consumption and low service life; in the use of the terminal for a long time and a long month, the resilience of the terminal cannot be ensured after long-time extrusion, and after the pressure extrusion, the terminal cannot be recovered, so that poor conduction of a product can be caused after the service time of the product is prolonged, and the signal transmission contact of the product is poor;

(2) The existing terminal is inconvenient to install in production, and has low assembly speed and low efficiency.

3. In the prior art, regarding the arrangement of strain gauges and the aspects of PCB boards and binding wires, there are at least three problems:

(1) An embodiment in which the sensing surface is at a horizontal angle, flat with strain gages is its first generation product, this embodiment being oversized; meanwhile, the three strain gauges are arranged in the scheme, so that the production cost of the product is increased, but the effect is not improved well in actual use;

(2) On the other hand, the pressure sensor applied to the automobile brake system at present has small product installation space, and because the pressure sensor is a high-pressure product, if the whole size can be reduced, the product can be lifted to a new height, so in order to reduce the size of the pressure sensor, in the prior art, a second generation product implementation mode of a sensing surface at a vertical angle and a side-release strain gauge is also adopted, the diameter of the product can be reduced, but the diameter of the product is reduced, because the stress point of the sensor is arranged on the side surface, the core of the product is the sensing surface, the sensing surface is absolutely flat, the machining of the side surface is difficult to ensure precision, the cost is high, the problem of uneven precision exists, the leveling precision is insufficient, and the product with uneven stress is difficult to calibrate; uneven stress also has insufficient structural stability, insufficient tolerance in the use process, easy temperature drift and time drift, low qualification rate and short service life of products;

(3) On the other hand, the above-mentioned scheme of side strain gauge reduces the product size, but there is a new problem that the circuit of the sensor needs to be amplified, converted, conditioned to process the original signal into digital output, and the conditioning chip size is minimum, lxW =4x4mm, no place is placed on the same PCB board, and the PCB is also reserved with a binding wire area. However, the space of the PCBA bonding pad communicated with the sensing module in the prior art is too small, so that the size of the sensing module cannot be too small in order to reserve enough space, and each electronic component and each binding wire are installed in a narrow space, so that the stability of an internal structure cannot be well ensured, the difficulty of binding wires or binding wires is extremely high, and the yield is low; the process is complex and the cost is high.

4. In the prior art, a dispensing process is adopted in a strain gauge mounting mode, so that the sensitivity in use cannot be effectively ensured.

5. In the prior art, the terminals are mounted in the terminal holder to prevent the terminals from being separated outwards, but the design scheme is high in cost and low in effect.

6. The frame construction among the prior art is inconvenient carries out effectual interval to inside PCBA, and space utilization and arrangement are unreasonable, and support and guard action are not strong.

7. The PCBA inside in the prior art is easy to shake and/or rotate in use, and the PCBA is small in size and inconvenient to fix.

Disclosure of Invention

The object of the present invention is to solve at least part of the above existing problems.

In order to solve the technical problems, the small-diameter high-pressure sensor of the present invention comprises:

the pressure sensing main body comprises a connecting end positioned at one end of the pressure sensing main body and a pressure receiving surface positioned at the other end of the pressure sensing main body; the pressure sensing main body is internally provided with a fluid hole, and one end of the fluid hole penetrates through the connecting end; a pressure sensing film is formed between the other end of the fluid hole and the pressure receiving surface;

the strain gauge is arranged on the pressure sensing film;

the pressure sensing main body is at least partially positioned in the shell and fixedly connected with one end of the shell;

a spring seat mounted at the other end within the housing and fixedly connected to the housing;

a snake pin needle fixedly mounted on the spring seat;

a first circuit board mounted in the housing at a horizontal angle, the first circuit board being between the strain gauge and the spring seat; the first circuit board is electrically connected with the strain gauge and the snake pin needle respectively.

As a preferred embodiment of the small diameter high pressure sensor of the present invention, the snake pin needle is a spring; the outer diameter of at least the lower part of the snake pin needle is larger than that of the upper Fang Waijing.

As a preferred embodiment of the small diameter high pressure sensor of the present invention, the spring seat has a connecting hole; the lower end part of the snake pin needle is arranged in the connecting hole;

the connecting device comprises a spring cover, wherein a first through hole is formed in the position, which is positioned on the same axis as the connecting hole, of the spring cover; the spring cover is fixedly connected with the spring seat and the shell and is positioned in the shell; the upper end of the snake pin needle is outside the spring cover through the first through hole.

As a preferred embodiment of the small-diameter high-pressure sensor of the present invention, the end of the housing connected to the spring cover has an annular inner snap edge, which abuts against the upper edge of the spring cover.

As a preferred embodiment of the small diameter high pressure sensor of the present invention, it comprises a second wiring board which is located within the housing and between the first wiring board and the spring seat; the second circuit board is arranged in parallel with the first circuit board;

The spring seat is abutted against the upper side of the second circuit board, and the snake pin needle is electrically connected with the second circuit board;

the circuit board comprises a third circuit board, and the first circuit board is electrically connected with the second circuit board through the third circuit board.

As a preferred embodiment of the small diameter high pressure sensor of the present invention, it comprises a first half-pack holder which at least partially abuts against the outer wall of the pressure-sensitive body and is fixedly connected thereto; a fixed integrated placing table is arranged at the upper end part of the first half bag bracket; the horizontal height of the placing table is higher than that of the strain gauge, and the placing table and the strain gauge are in parallel height;

the first circuit board is mounted on the placing table.

As a preferred embodiment of the small diameter high pressure sensor of the present invention, it comprises a second half-pack holder that at least partially abuts the outer wall of the pressure-sensing body; one end of the second half-package support is fixedly connected with the pressure sensing main body, and the other end of the second half-package support is abutted to the lower portion of the second circuit board.

As a preferred embodiment of the small-diameter high-pressure sensor, a first limit notch at a horizontal angle is arranged on the side surface of the first half-package support, which is abutted against the second half-package support;

The joint of the second half-package support and the second circuit board is provided with a second limit notch which is communicated with the second half-package support and the second circuit board at the same time; the second limiting notch is positioned at a longitudinal angle;

the second half-bag support comprises a first limiting block, and the first limiting block is positioned in the first limiting gap when the first half-bag support abuts against the second half-bag support;

the second limiting block is fixedly connected to the lower portion of the spring seat, and is located in the second limiting notch when the spring seat abuts against the second circuit board.

As a preferred embodiment of the small-diameter high-pressure sensor of the present invention, the first wiring board and the second wiring board are PCBs;

the third circuit board is an FPC.

In order to solve the technical problems, the manufacturing method of the small-diameter high-pressure sensor adopts a pressure sensing main body with an integrated structure, wherein one end of the pressure sensing main body is a connecting end, and the other end of the pressure sensing main body is a pressed surface;

arranging a fluid hole in the pressure sensing main body, enabling one end of the fluid hole to penetrate through the connecting end and the other end of the fluid hole to be positioned close to the pressure receiving surface, and forming a pressure sensing film between the fluid hole and the pressure receiving surface;

Sand blasting is carried out on the pressed surface;

cleaning the pressure sensing main body;

performing glass cement silk screen printing on the pressed surface, and sintering the silk screen printed pressure sensing main body;

setting a strain gauge on the surface of the pressure sensing film of the pressure receiving surface;

aging the pressure sensing main body after the steps are completed;

welding a first half-pack bracket to the pressure sensing body;

arranging a first circuit board and a second circuit board for increasing the binding wire area; the first circuit board and the second circuit board are respectively and horizontally arranged and are in parallel angles; electrically connecting the first circuit board with the second circuit board through a third circuit board which is arranged vertically;

bonding a first circuit board to the first half-wrapping bracket, and completing binding wires of the first circuit board and the strain gauge; the first circuit board is parallel to the strain gauge;

welding a second half-wrapping support, wherein the height of the second half-wrapping support is larger than that of the first half-wrapping support, and at least the overlapping area of the first half-wrapping support and the second half-wrapping support is enclosed into a closed circle;

a second circuit board is fixed through a second half-package bracket;

a spring seat and a spring cover are arranged vertically above the second circuit board;

The method comprises the steps of installing a snake pin needle in a spring seat, limiting the snake pin needle in the spring seat through a spring cover, and enabling the snake pin needle to be electrically connected with a second circuit board;

assembling the components in a shell, welding the pressure sensing main body with the lower end part of the shell, and sealing the spring cover with the upper end part of the shell;

and testing the product and warehousing.

In order to solve the technical problems, the manufacturing method of the small-diameter high-pressure sensor comprises the steps of, based on all or any of the foregoing summary,

deleting the second half-package support, the spring seat, the spring cover and the second circuit board;

adding an integral bracket in the shell, wherein the upper end part of the integral bracket is provided with a second through hole which is gradually smaller from bottom to top; wherein the external diameter of the snake pin needle is matched with the second through hole; and the snake pin is fixedly connected in the second through hole and is electrically connected with the third circuit board.

In order to solve the technical problems, the diameter reduction method of the high-pressure sensor comprises the steps of, based on all or any of the foregoing summary,

the first circuit board and the second circuit board which are arranged in parallel are used for increasing the binding wire area, and the third circuit board is electrically connected with the first circuit board and the second circuit board, so that the pad space of the PCBA is increased, and the overall size of the high-pressure sensor is reduced.

Advantageous effects

The present invention solves the above existing problems and other existing problems not mentioned one by one above and brings at least the following innovative advantages accordingly:

1. the pressure sensing main body of the small-diameter high-pressure sensor adopts an integrated structure, and is integrally processed and molded, so that when the product is pressed against the internal structure after being stressed at high pressure, the stress surface of the product is deformed, and the pressure sensing main body has a better temperature-resistant and impact-resistant structure. In the pressure and temperature impact process, the design is integrally formed, so that the stability of the product is improved, and the adverse hidden troubles of insufficient pressure resistance, leakage, breakage, oil leakage and the like of the product in the subsequent use process are avoided; the sensor is stable in stress, the overall strength is improved, and the signal transmission stability of the product is improved; the service life of the product is also prolonged; the problems that the structural stability and the tolerance of the existing product are insufficient, weld cracks can occur under long-term impact, leakage is easy to occur, the internal structure of the product is loose, binding wires are broken, the product is invalid, and the service life of the product is short are solved.

2. According to the invention, the screen printing is performed on the pressed surface, so that the position of the strain gauge can be ensured to be within the precision range, and the sensitivity of the product can be ensured. Solves the problem that the sensitivity of the dispensing process adopted in the prior art cannot be effectively ensured.

3. According to the invention, the structure of the snake pin needle is set to be at least the outer diameter of the lower part of the structure is larger than that of the upper part Fang Waijing, so that the snake pin needle cannot be separated after the installation is completed, the stability of the snake pin needle is improved, and the problem that the terminal is prevented from being separated outwards by installing the terminal in the terminal holder in the prior art is solved, but the design scheme has a small effect. In the use of the product, the medium in the signal transmission process needs to have at least the characteristic of good rebound resilience, so that the spring is preferably adopted to transmit the signal by the snake pin needle, and the condition of poor rebound resilience is not easy to exist in the use process. Meanwhile, in the implementation, the material of the snake pin needle is SUS304L and is prepared by gold plating on the surface, so that the snake pin needle has better signal transmissibility and rebound resilience, and has the advantages that the snake pin needle can still normally recover the original shape after being bent for many times in the use process, the contact is good, and the signal output is more stable; the terminal in the prior art is manufactured by bending a metal sheet, and has the advantages of high production cost, long time consumption and low service life; in the use of the terminal in the long-term month, the elasticity can not be guaranteed after long-time extrusion, after the pressure extrusion, the terminal can not be restored, and the problem that poor conduction of a product can be caused after the service time of the product is prolonged, so that poor contact of a product transmission signal is caused.

4. According to the invention, through the arranged spring seat and the connecting hole arranged in the spring seat, the quick installation of the snake pin needle can be realized, and the electric connection between the snake pin needle and other parts can be realized; solves the following problems:

(1) The problems of inconvenient installation, low assembly speed and low efficiency in the terminal production in the prior art are solved. Simultaneously, the spring cover is combined, so that the effect of limiting the snake pin needle is achieved;

(2) The problem that in the prior art, through installing the terminal in the terminal holder to prevent the terminal outwards separates, but this design scheme is not only with high costs, and the effect is not big has also been solved together simultaneously.

5. A third circuit board is arranged between the first circuit board and the second circuit board; the first circuit board, the second circuit board and the third circuit board form a similar -shaped structure. The second circuit board is used for placing a conditioning chip; the first circuit board is used for placing the bonding pad, enough space is reserved for facilitating wire binding and welding, limited internal space of the sensor is utilized to the maximum extent, and space utilization rate is improved; the third circuit board in the middle position can be used for placing electronic components such as amplification, transposition and the like. The structure, the angle, the positions and the connection relation among the first circuit board, the second circuit board and the third circuit board at least bring the following three advantages and solve the corresponding existing problems:

(1) According to the invention, through the first circuit board and the second circuit board which are arranged in parallel, the two circuit boards are used for increasing the binding wire area and are matched with the third circuit board at a vertical angle, the binding wire process is greatly optimized, the space or the welding disc area of the PCBA is greatly increased, and the utilization rate of the space is increased, so that the diameter of a product can be greatly reduced in a production link, and the problem that the size of a first-generation product is overlarge due to the implementation scheme of the strain gauge with a sensing surface at a horizontal angle in the prior art is solved. Meanwhile, one or two strain gauges are arranged in combination with the invention, so that the cost of a production link is reduced; the problem that the production cost of a product is increased due to the fact that three strain gauges are arranged in the prior art, but the effect is not improved in actual use is solved;

(2) The first circuit board and the second circuit board are arranged in parallel, the two circuit boards are equal to the binding wire area with two identical diameters, and the third circuit board at a vertical angle is matched, so that binding wires can be realized on the basis of small size; the strain gauge is positioned at the front horizontal position, so that the production difficulty can be reduced, the production efficiency can be improved, and the yield of products can be greatly improved; the cost is low, the film processing precision of the pressure-sensitive film is high, the stress is uniform, the structure is stable, the tolerance is large, the qualification rate is high, the service life of the product is long, and the temperature drift and time drift can not be caused. The invention increases the utilization rate of space, solves the problem of large size of the strain gauge horizontally placed in the prior art, solves the problem that the accuracy is difficult to guarantee during machining of the strain gauge horizontally placed in the prior art, has high cost, and can lead to uneven accuracy, uneven flatness accuracy and uneven stress of products, and difficult calibration; uneven stress also has the problems of insufficient structural stability, insufficient tolerance in the use process, easy temperature drift and time drift, low qualification rate and short service life of products. Compared with the prior art of laterally placing strain gauges, the invention greatly increases the binding wire area in the aspect of reducing the product size, and can further produce the product with smaller and more precise size.

(3) The stability of the sensor needs to be ensured due to the internal structure of the sensor, but the sensor is limited in structural space; therefore, the invention utilizes the space to the maximum extent through the parallel arrangement of the first circuit board and the second circuit board, the two circuit boards are equal to the binding wire area with two identical diameters and are matched with the third circuit board at a vertical angle, the double-layer structure formed by the first circuit board and the second circuit board increases the utilization rate of the space-! The invention solves the problems that the scheme of the side-placed strain gauge in the prior art reduces the product size, but reserves enough space to avoid the situation that the size of each electronic component cannot be too small because the electronic component is not placed on the same PCB (printed circuit board) in enough positions, and each electronic component and binding wire are installed in a narrow space, so that the stability of an internal structure cannot be well ensured, the difficulty of binding wires or binding wires cannot be extremely high, and the yield is low; the process is complex and the cost is high.

6. According to the invention, the placing table arranged on the first half-package support is used for enabling the first circuit board arranged on the placing table to be adjacent to the strain gauge, and keeping a certain distance, so that the first circuit board is prevented from touching the strain gauge by mistake; according to the invention, the second half-package bracket matched with the first half-package bracket not only plays a role in supporting the second circuit board, but also plays a role in reserving space for the third circuit board through the arc-shaped structure of the second half-package bracket; the problem of among the prior art frame construction be inconvenient for carrying out effectual interval to inside PCBA, space utilization and arrange unreasonable, and support and guard action are not strong is solved.

7. According to the invention, through the cooperation of the first limiting notch and the first limiting block, the connection between the first half-bag support and the second half-bag support is firmer, namely the upper part of the first half-bag support is firmer indirectly, and the placing table above the first half-bag support is firmer in use. Meanwhile, the second half-package bracket, the second circuit board and the spring seat are mutually matched through the matching of the second limiting notch and the second limiting block, so that the stability of the whole structure is further improved. And the first limiting notch is positioned at a horizontal angle, and the second limiting notch is positioned at a longitudinal angle, so that the horizontal direction and the longitudinal direction are both reinforced. In addition, the third limiting block and the third limiting notch and the second limiting block port and the second limiting notch are arranged, so that the first circuit board and the second circuit board are further fixed, and the angle and the position of the first circuit board and the second circuit board are prevented from moving; the problem of among the prior art inside PCBA in use rock and/or rotate easily, and PCBA size is again little, inconvenient fixed is solved.

8. The first circuit board and the second circuit board are PCBs; wherein the third circuit board is an FPC. The third circuit board adopts the FPC, so that on one hand, the occupation of the internal space is reduced, the limited internal space of the sensor is further utilized to the maximum extent, and the utilization rate of the space is increased; on the other hand, the first circuit board and the second circuit board are arranged at a horizontal angle, so that the first circuit board and the second circuit board are electrically connected.

9. The invention discloses a manufacturing method of a small-diameter high-pressure sensor, which comprises the steps of deleting a second half-package support, a spring seat, a spring cover and a second circuit board in the small-diameter high-pressure sensor; and adding an integral bracket in the shell, wherein the upper end part of the integral bracket is provided with a second through hole which is gradually smaller from bottom to top; wherein the external diameter of the snake pin needle is matched with the second through hole; the snake pin is fixedly connected in the second through hole and is electrically connected with a third circuit board in the second through hole; therefore, on the one hand, the method plays a role in further reducing the cost on the basis of the small-diameter high-pressure sensor; on the other hand, the snake pin needle is arranged in the second through hole and has an anti-falling effect; and the whole bracket is used as a support, the second half-wrapping bracket is abandoned, the space is optimized on the premise of ensuring the integrity, and the assembly efficiency is greatly improved.

10. According to the diameter reduction method of the high-pressure sensor, the first circuit board and the second circuit board which are arranged in parallel are used for increasing the binding wire area, and the first circuit board and the second circuit board are electrically connected through the third circuit board, so that the binding wire area equivalent to the large-size high-pressure sensor is obtained through accumulation of at least two circuit boards which are arranged in parallel on the basis of small size; to increase the pad space of the PCBA (i.e. increase the utilization of space) and reduce the overall size of the high-pressure sensor.

Drawings

Fig. 1 is a perspective view of embodiment 1 and embodiment 2 of the present invention;

FIG. 2 is a top view of FIG. 1;

FIG. 3 is a partially exploded view of FIG. 1;

FIG. 4 is an exploded view of FIG. 1;

FIG. 5 is a cross-sectional view of the "A-A" position of FIG. 2;

FIG. 6 is a cross-sectional view of the "B-B" position of FIG. 2;

FIG. 7 is an enlarged partial view of the area "A" in FIG. 5;

FIG. 8 is an enlarged view of a portion of the area "B" of FIG. 5;

FIG. 9 is a perspective view of a component "spring seat" of the present invention;

FIG. 10 is a perspective view of the component "spring cover" of the present invention;

FIG. 11 is a perspective view of the components "first circuit board", "second circuit board" and "third circuit board" of the present invention;

FIG. 12 is a perspective view of the component "second half-pack bracket" of the present invention;

FIG. 13 is a perspective view of the component "first half-pack holder" of the present invention;

FIG. 14 is a perspective view of the component "pressure sensing body" of the present invention;

FIG. 15 is a cross-sectional view of FIG. 14;

FIG. 16 is a partial installation effect diagram of the "strain gage" of the present invention;

FIG. 17 is a partial effect view of the "strain gage" binding wire of the present invention;

FIG. 18 is a graph showing the effect of deformation of the pressure-sensitive film of the present invention;

FIG. 19 is a circuit diagram of the present invention;

FIG. 20 is a graph showing the deformation effect of the pressure sensing film of the present invention;

FIG. 21 is a perspective view of embodiment 3 of the present invention;

FIG. 22 is a partially exploded view of FIG. 21;

FIG. 23 is an exploded view of FIG. 21;

FIG. 24 is a perspective view of a component "integral bracket" of the present invention;

fig. 25 is a partial process flow diagram of the present invention.

In the figure: 1. the pressure sensing body 2, the connecting end 3, the pressure bearing surface 4, the fluid hole 5, the pressure sensing film 6, the strain gauge 7, the shell 8, the spring seat 9, the snake pin needle 10, the first circuit board 11, the connecting hole 12, the spring cover 13, the first through hole 14, the annular inner fastening edge 15, the second circuit board 16, the third circuit board 17, the first half-package support 18, the placing table 19, the second half-package support 20, the first limiting gap 21, the second limiting gap 22, the first limiting block 23, the second limiting block 24, the integral support 25, the second through hole 26, the third limiting gap 27.

Detailed Description

In order to make the objects, technical solutions and advantages of the technical solutions of the present disclosure more clear, the technical solutions of the embodiments of the present disclosure will be clearly and completely described below with reference to the drawings of the specific embodiments of the present disclosure.

Like reference numerals in the drawings denote like parts. It should be noted that the described embodiments are some, but not all embodiments of the present disclosure.

All other embodiments, which can be made by one of ordinary skill in the art without the need for inventive faculty, are within the scope of the present disclosure, based on the described embodiments of the present disclosure.

( The invention will now be described in further detail with reference to the accompanying drawings. The figures are simplified schematic representations which merely illustrate the basic structure of the invention and which therefore only show the construction which is relevant for the invention )

Exemplary embodiments of the present invention are as follows.

Example 1

The process flow of the invention, see fig. 25, is summarized as follows:

the first step: checking raw material supply, including at least appearance and size;

and a second step of: the method comprises the steps of performing sand blasting on a pressed surface 3 of a pressure sensing main body 1 to enable the pressed surface to meet process requirements;

And a third step of: automatically cleaning the pressure sensing main body 1 to at least remove dirt and greasy dirt on the surface;

fourth step: carrying out glass cement silk screen printing on the pressed surface 3;

fifth step: sintering the pressure sensing main body 1 subjected to screen printing;

sixth step: placing a strain gauge 6 on the sintered glass;

seventh step: bonding;

eighth step: aging the sintered pressure-sensitive body 1; the specific operation of aging is as follows: placing the product into a high temperature furnace, and placing the product at 250 ℃ for 48 hours to remove the stress of the metal material;

ninth step: performing appearance inspection on the aged pressure-sensitive body 1, including the position of the strain gauge;

tenth step: welding a first half-pack bracket;

eleventh step: bonding PCBA (first, second and third wiring boards 10, 15 and 16, fixing binding wire PCBA;

twelfth step: finishing binding wires and checking;

thirteenth step: welding a second half-package bracket to fix a second circuit board 15;

fourteenth step: mounting a snake pin needle 9, a spring seat 8 and a spring cover 12, assembling a shell 7, and welding the shell 7 after the assembly is completed;

fifteenth step: insulation test, overvoltage test, calibration test and functional test;

sixteenth step: packaging, inspecting and warehousing.

The details of the above links, at least the key parts, are as follows:

the small diameter high pressure sensor of the present invention, see fig. 1-20; comprising the following steps: a pressure sensing main body 1, wherein the pressure sensing main body 1 comprises a connecting end 2 positioned at one end of the pressure sensing main body and a pressure receiving surface 3 positioned at the other end of the pressure sensing main body; wherein fig. 14 and 15 show that the pressure sensing body 1 has a fluid hole 4 therein, one end of the fluid hole 4 penetrates through the connection end 2, and the other end is located adjacent to the compression surface 3; a pressure-sensitive film 5 is formed between the other end of the fluid hole 4 and the pressure receiving surface 3. See fig. 25, wherein the pressure-sensitive surface 3 is sandblasted and the pressure-sensitive body 1 is cleaned in practice; and silk-screen printing is carried out on the pressed surface 3, and the pressure sensing main body 1 with the silk-screen printing is sintered. The pressure sensing main body 1 of the component of the invention abandons the implementation mode that the sensing part of the existing product is formed by welding MIM Port and Port, and changes the part of the connecting end 2 and the part of the pressure receiving surface 3 into an integral structure. In a great deal of research experiments of the applicant, the main reason of the insufficient pressure resistance of the existing product is that the MIM Port and the Port are easy to leak due to the adoption of a welding mode, and the pressure sensing main body 1 of the invention adopts an integrated structure, so that the stress surface of the product is deformed when the product extrudes the internal structure after being stressed at high pressure by integrated processing and forming, and the pressure sensing main body has a better temperature-resistant and impact-resistant structure. In the pressure and temperature impact process, the design is integrally formed, so that the stability of the product is improved, and the adverse hidden troubles of insufficient pressure resistance, leakage, breakage, oil leakage and the like of the product in the subsequent use process are avoided; the sensor is stable in stress, the overall strength is improved, and the signal transmission stability of the product is improved; the service life of the product is also prolonged; the problems that the structural stability and the tolerance of the existing product are insufficient, weld cracks can occur under long-term impact, leakage is easy to occur, the internal structure of the product is loose, binding wires are broken, the product is invalid, and the service life of the product is short are solved.

On the other hand, the invention ensures that the position of the strain gauge 6 can be ensured in the precision range and the product sensitivity can be ensured by silk-screen printing the pressed surface 3. Solves the problem that the sensitivity of the dispensing process adopted in the prior art cannot be effectively ensured.

Fig. 14 and 15 show the positions of the strain gages 6, wherein one or two strain gages 6 are provided on the pressure-sensitive film 5; fig. 14 to 18 show that the strain gage 6 is disposed on the surface of the pressure sensitive film 5 of the pressure receiving surface 3; wherein fig. 16 shows a partial effect diagram of the installation of the strain gage 6; fig. 17 shows a partial effect diagram of the strain gage 6 binding wire; FIG. 18 shows an effect diagram of deformation of the pressure-sensitive film 5 caused by pressure induction, when the pressure of the gas or the liquid exists in the fluid hole 4, the pressure-sensitive film 5 is slightly deformed, and the resistance of the strain gauge 6 sintered on the pressure-sensitive film 5 is correspondingly changed; FIG. 19 shows a circuit diagram of binding wires connected to form a Wheatstone bridge, wherein the strain gauge binding wires are connected to form a Wheatstone bridge, which generates a voltage proportional to pressure when the bridge is energized with a voltage; the signal is amplified and processed by the conditioning chip and converted into analog or digital signal to be output. Fig. 20 shows that the pressure-sensitive film 5 deforms, and the deformation is fed back through the wheatstone bridge to form an electrical signal, which is the prior art and will not be described in detail herein.

Comprising a housing 7, fig. 3 to 6 respectively showing the specific structure of the housing 7 and its installation position from different angles, said pressure-sensitive body 1 being at least partially inside said housing 7 and being fixedly connected to one end of said housing 7; fig. 5 and 6 show that the part above the pressure-sensitive body 1 (the end of the pressure-receiving surface 3) is located in the housing 7 and fixedly connected to the housing 7.

Fig. 3 to 6 show the specific structure of the spring seat 8 and its installation position, respectively, from different angles, wherein fig. 9 is a perspective enlarged view of the spring seat 8, and the spring seat 8 is installed at the other end in the housing 7 and fixedly connected with the housing 7.

Comprising the components snake pin needle 9, figures 5 and 6 respectively show that said snake pin needle 9 is fixedly mounted to said spring seat 8.

Fig. 3 to 6 show a first circuit board 10, see fig. 5 and 6, respectively, the first circuit board 10 being mounted in the housing 7 at a horizontal angle, the first circuit board 10 being located between the strain gauge 6 and the spring seat 8; the first circuit board 10 is electrically connected to the strain gauge 6 and the snake pin needle, respectively.

Based on the foregoing, wherein the preferred embodiment of the said snake pin needle 9 has been compared through extensive experimental analysis, the said snake pin needle 9 preferably employs a spring in this example; and fig. 4 at least fig. 6 shows from a different angle that the outer diameter of the at least lower part of the said snake pin needle 9 is larger than the upper Fang Waijing. According to the invention, the structure of the snake pin needle 9 is set to be at least the outer diameter of the lower part of the structure is larger than that of the upper part Fang Waijing, so that the snake pin needle 9 cannot be separated after being installed, the stability of the snake pin needle 9 is improved, and the problem that the terminal is prevented from being separated outwards by installing the terminal in the terminal holder in the prior art is solved, but the design scheme has a small effect. In the use of the product, the medium in the signal transmission process needs to have at least the characteristic of good rebound resilience, so that the medium must be restored to the original state after being used in the use process, and the spring is preferably adopted for transmitting the signal by the snake pin needle 9, so that the condition of poor rebound resilience is not easy to occur. Meanwhile, in the implementation, the snake pin needle 9 is made of SUS304L and is plated with gold on the surface, so that the snake pin needle has better signal transmissibility and rebound resilience, and has the advantages that after being bent for many times in the use process, the snake pin needle can still recover the original shape normally, ensure good contact and more stable signal output; the terminal in the prior art is manufactured by bending a metal sheet, and has the advantages of high production cost, long time consumption and low service life; in the use of the terminal in the long-term month, the elasticity can not be guaranteed after long-time extrusion, after the pressure extrusion, the terminal can not be restored, and the problem that poor conduction of a product can be caused after the service time of the product is prolonged, so that poor contact of a product transmission signal is caused.

On the basis of the foregoing, further, wherein fig. 4 to 6 and 9 respectively show the spring seat 8 from different angles with a connecting hole 11; the aperture and the structure of the connecting hole 11 are matched with the lower part of the snake pin needle 9; the lower end part of the snake pin needle 9 is arranged in the connecting hole 11; the exploded view of fig. 4, the sectional views of fig. 5 and 6, and the partial enlarged view of fig. 7 show that the lower part of the snake pin needle 9 is conical, respectively, and fig. 7 shows that the diameter of the port below the connection hole 11 is smaller than that of the upper part, so that the port below the connection hole 11 only allows part of the end of the spring to pass through, thereby realizing that the snake pin needle 9 is directly or indirectly electrically connected with the first circuit board 10.

Comprising a spring cover 12, fig. 5 shows that the spring cover 12 and the connecting hole 11 are positioned on the same axis and provided with a first through hole 13; fig. 10 shows a perspective view of the spring cover 12, and shows the specific shape and position of the first through hole 13, the diameter of the first through hole 13 is smaller than the diameter of the connecting hole 11, and the diameter of the first through hole 13 is matched with the diameter above the snake pin needle 9; figures 3, 5 and 6 show that the spring cover 12 is fixedly connected to the spring seat 8 and the housing 7 and is located in the housing 7; fig. 5 and 6 show the upper end of the snake pin needle 9 outside the spring cover 12 through the first through hole 13. According to the invention, through the arranged spring seat 8 and the connecting hole 11 arranged in the spring seat 8, the quick installation of the snake pin needle 9 can be realized, and the electric connection between the snake pin needle 9 and other parts can be realized; 1. the problems of inconvenient installation, low assembly speed and low efficiency in the production of the terminals in the prior art are solved. And meanwhile, the spring cover 12 is combined, so that the function of limiting the snake pin needle 9 is achieved. 2. Meanwhile, the problem that in the prior art, the terminals are mounted in the terminal holder to prevent the terminals from being separated outwards, but the design scheme is high in cost and low in effect is solved.

As shown in fig. 3 to 6, the end of the housing 7 connected to the spring cover 12 has an annular inner fastening edge 14, and the annular inner fastening edge 14 abuts against the upper edge of the spring cover 12. The annular inner buckling edge 14 arranged through the shell 7 can limit the spring cover 12 after the spring cover 12 is installed.

On the basis of the first circuit board 15, the circuit board further comprises a second circuit board 15, and fig. 5 and 6 show that the second circuit board 15 is located in the housing 7 and between the first circuit board 10 and the spring seat 8; the second circuit board 15 is disposed parallel to the first circuit board 10; by further adding the second circuit board 15, the aforementioned snap pin 9 is preferably electrically connected to the second circuit board 15. Fig. 5 to 8 show the position of the second circuit board 15 and the connection relationship with other components on the upper and lower sides, the spring seat 8 abuts against the upper side of the second circuit board 15, and the snake pin 9 is electrically connected with the second circuit board 15. And fig. 3 to 8 show that the circuit board further comprises a third circuit board 16, and the first circuit board 10 and the second circuit board 15 are electrically connected through the third circuit board 16. Wherein the exploded view of fig. 4 and the enlarged view of the component of fig. 11 show the first wiring board 10 and the second wiring board 15 arranged in parallel, and the third wiring board 16 is disposed between the first wiring board 10 and the second wiring board 15; the first circuit board 10, the second circuit board 15 and the third circuit board 16 form a similar structure like a letter. In production implementation, the second circuit board 15 above is shown in fig. 5 to 7, and is used for placing conditioning chips; the first circuit board 10 below is used for placing a bonding pad, enough space is reserved for facilitating binding wires and welding, limited internal space of the sensor is utilized to the maximum extent, and space utilization rate is improved; the third circuit board 16 in the middle position may be used to place electronic components such as amplification and transposition (the electronic components placed on the third circuit board 16 are well known to those skilled in the art, and will not be described herein in detail).

The structure, angle, said positions and the connection relation between the first circuit board 10, the second circuit board 15 and the third circuit board 16 at least bring the following advantages and solve the existing problems:

(1) According to the invention, through the first circuit board 10 and the second circuit board 15 which are arranged in parallel, the two circuit boards are used for increasing the binding wire area and are matched with the third circuit board 16 which is positioned at the vertical angle, the binding wire process is greatly optimized, the space or the welding disc area of the PCBA is greatly increased, and the space utilization rate is increased, so that the diameter of a product can be greatly reduced in the production link, and the problem that the size of a first-generation product is overlarge in the embodiment of the strain gauge with the sensing surface positioned at the horizontal angle in the prior art is solved. Meanwhile, one or two strain gauges 6 are arranged in combination with the invention, so that the cost of the production link is reduced; the problem that the production cost of a product is increased due to the fact that three strain gauges are arranged in the prior art, but the effect is not improved in actual use is solved;

(2) The invention can realize binding wires on the basis of small size by arranging the first circuit board 10 and the second circuit board 15 in parallel, wherein the two circuit boards are equal to the binding wire area with two identical diameters and are matched with the third circuit board 16 at a vertical angle; the strain gage 6 is positioned at the front horizontal position, so that the production difficulty can be reduced, the production efficiency can be improved, and the yield of products can be greatly improved; the cost is low, the film processing precision of the pressure sensing film 5 is high, the stress is uniform, the structure is stable, the tolerance is large, the qualification rate is high, the service life of the product is long, and the temperature drift and time drift can not be caused. The invention increases the utilization rate of space, solves the problem of large size of the strain gauge horizontally placed in the prior art, solves the problem that the accuracy is difficult to guarantee during machining of the strain gauge horizontally placed in the prior art, has high cost, and can lead to uneven accuracy, uneven flatness accuracy and uneven stress of products, and difficult calibration; uneven stress also has the problems of insufficient structural stability, insufficient tolerance in the use process, easy temperature drift and time drift, low qualification rate and short service life of products. Compared with the prior art of laterally placing strain gauges, the invention greatly increases the binding wire area, and can further produce smaller and more precise product size;

(3) The stability of the sensor needs to be ensured due to the internal structure of the sensor, but the sensor is limited in structural space; therefore, the invention uses the space to the maximum extent through the parallel arrangement of the first circuit board 10 and the second circuit board 15, the two circuit boards are equal to the binding wire area with two identical diameters and are matched with the third circuit board 16 at a vertical angle, the double-layer structure formed by the first circuit board 10 and the second circuit board 15 increases the space utilization rate-! The invention solves the problems that the scheme of the side-placed strain gauge in the prior art reduces the product size, but reserves enough space to avoid the situation that the size of each electronic component cannot be too small because the electronic component is not placed on the same PCB (printed circuit board) in enough positions, and each electronic component and binding wire are installed in a narrow space, so that the stability of an internal structure cannot be well ensured, the difficulty of binding wires or binding wires cannot be extremely high, and the yield is low; the process is complex and the cost is high.

Comprising a first half-pack support 17, fig. 13 shows the three-dimensional structure of the first half-pack support 17; the first half-bag support 17 at least partially abuts against the outer wall of the pressure-sensitive body 1 and is fixedly connected to the pressure-sensitive body 1, preferably by laser welding; fig. 5 and 6 show that the lower end of the first half-pack bracket 17 abuts against the pressure-sensitive body 1 and is connected with the pressure-sensitive body 1; referring to fig. 13, a fixed integral placement table 18 is provided at the upper end of the first half-pack bracket 17; figures 5 and 6 show the placement stage 18 at a level higher than the strain gauge 6, the placement stage 18 being at a level with the strain gauge 6; the first circuit board 10 is fixedly mounted on the placement stage 18.

Further comprising a second semi-bag support 19, fig. 12 shows a specific structure of the second semi-bag support 19, and fig. 5 and 6 show connection relation between the second semi-bag support 19 and other components, wherein the second semi-bag support 19 at least partially abuts against the outer wall of the pressure sensing main body 1; one end of the second half-package support 19 is fixedly connected with the pressure sensing main body 1, and the other end of the second half-package support abuts against the lower side of the second circuit board 15. Referring to fig. 5 and 6, the lower end of the second half-pack bracket 19 abuts against the pressure sensing main body 1, and the upper end of the second half-pack bracket 19 abuts against the lower side of the second circuit board 15, so that the second circuit board 15 is located between the second pack closing bracket 19 and the spring seat 8; the second half-bag holder 19 has a height greater than the first half-bag holder 17, wherein the third circuit board 16 is located at the notch of the second half-bag holder 19. Fig. 3 shows that the first half-wrapping support 17 and the second half-wrapping support 19 are respectively arc-shaped structures, and when the first half-wrapping support 17 and the second half-wrapping support 19 are abutted, at least the abutted portions are enclosed to form a closed circle. The first circuit board 10 arranged on the placing table 18 is adjacent to the strain gauge 6 through the placing table 18, and a certain interval is kept between the first circuit board 10 and the strain gauge 6, so that the first circuit board 10 is prevented from being mistakenly touched to the strain gauge 6; the second half-package bracket matched with the first half-package bracket 17 not only plays a role in supporting the second circuit board 15, but also plays a role in reserving space for the third circuit board 16 through the arc-shaped structure of the second half-package bracket; the problem of among the prior art frame construction be inconvenient for carrying out effectual interval to inside PCBA, space utilization and arrange unreasonable, and support and guard action are not strong is solved.

Fig. 13 shows a case in which the side of the first half-pack support 17 abutting against the second half-pack support 19 is provided with a first limit notch 20 at a horizontal angle; the number of the first limiting notches 20 is at least one. And the second semi-enclosed bracket perspective view of fig. 12 and the partially exploded view of fig. 3 show that the abutting part of the second semi-enclosed bracket 19 and the second circuit board 15 is provided with a second limiting notch 21 which communicates with the second semi-enclosed bracket 19 and the second circuit board 15 simultaneously, that is, the second semi-enclosed bracket 19 and the second circuit board 15 respectively have the second limiting notch 21, and when the second semi-enclosed bracket 19 and the second circuit board 15 abut, the second limiting notch 21 of the two is communicated. The second limiting notch 21 is at a longitudinal angle. Meanwhile, fig. 12 shows that the second half-bag bracket 19 comprises first limiting blocks 22, and the number, the size and the shape of the second limiting blocks 22 are matched with those of the first limiting gaps 20; fig. 3 shows that the first limiting block 22 is located in the first limiting notch 20 when the first half-pack bracket 17 abuts against the second half-pack bracket 19. In addition, fig. 9 shows that a second limiting block 23 is fixedly connected below the spring seat 8, and fig. 3 shows that the second limiting block 23 is located in the second limiting notch 21 when the spring seat 8 abuts against the second circuit board 15. The invention makes the connection of the first half-bag support 17 and the second half-bag support 19 more stable through the cooperation of the first limiting notch 20 and the first limiting block 22, and indirectly makes the upper part of the first half-bag support 17 more stable, and makes the placing table 18 above the first half-bag support 17 more stable in use. Meanwhile, the second half-bag bracket 19, the second circuit board 15 and the spring seat 8 are mutually matched through the matching of the second limiting notch 21 and the second limiting block 23, so that the stability of the whole structure is further improved. And the first limiting notch 20 is at a horizontal angle, and the second limiting notch 21 is at a longitudinal angle, so that the horizontal direction and the longitudinal direction are reinforced. Fig. 11 shows that the first circuit board 10 has a third limit notch 26, and fig. 13 shows that a third limit block 27 fixedly connected above the first half-pack bracket 17 is provided, and the height of the third limit block 27 is higher than that of the placement table 18; fig. 3 shows that the third limiting block 27 is located in the third limiting notch 26 when the first circuit board 10 is mounted on the placement table 18. According to the invention, through the arrangement of the third limiting block 27 and the third limiting notch 26 and the arrangement of the second limiting block port 23 and the second limiting notch 21, the functions of fixing the first circuit board 10 and the second circuit board 15 are achieved, so that the angles and the positions of the first circuit board 10 and the second circuit board 15 are prevented from moving; the problem of among the prior art inside PCBA in use rock and/or rotate easily, and PCBA size is again little, inconvenient fixed is solved.

The above components are preferably SUS304L in terms of the material except that the material of the snake pin needle 9 is SUS304L and gold plating is performed on the surface, wherein the material of the first half-bag holder 17 and the second half-bag holder 19 is preferably SUS304L; wherein the first circuit board 10 and the second circuit board 15 are made of FR4 material; wherein the shell 7 is preferably made of SUS316L steel; wherein the spring cover 12 is preferably made of PBT.

Example 2

The small diameter high pressure sensor of the present invention, this example 2 includes all embodiments of example 1, where the same points are not repeated, except that:

wherein the first circuit board 10 and the second circuit board 15 are PCBs; wherein the third wiring board 16 is an FPC. By adopting the FPC for the third circuit board 16, the occupation of the internal space is reduced, the limited internal space of the sensor is utilized to the greatest extent, and the utilization rate of the space is increased; on the other hand, the first circuit board 10 and the second circuit board 15 are arranged at a horizontal angle, so that the first circuit board 10 and the second circuit board 15 are electrically connected.

Example 3

The manufacturing method of the small-diameter high-pressure sensor in this embodiment 3 includes all the embodiments of the embodiments 1 and 2, in which the same points are not described in detail, except that:

The second half-pack holder 19, spring seat 8, spring cover 12, and second wiring board 15 in embodiment 1 and embodiment 2 were deleted;

and on the basis of this, an integral bracket 24 is added in the housing 7, see fig. 21 and 24, fig. 21 being a perspective view of embodiment 3; FIG. 22 is a partially exploded view of FIG. 21; FIG. 23 is an overall exploded view of FIG. 21;

fig. 24 is a perspective view of the integral stand 24 in embodiment 3; wherein the upper end of the integral bracket 24 is provided with a second through hole 25 which is gradually smaller from bottom to top; wherein the external diameter of the snake pin needle 9 is matched with the second through hole 25; the snake pin 9 is fixedly connected in the second through hole 25 and is electrically connected with the third circuit board 16 therein. The outer diameter of the snake pin needle 9 is also gradually reduced from bottom to top, and therefore the snake pin needle is mounted in the second through hole 25 to have an anti-falling effect. Referring to fig. 22 and 23, in the process of designing the PCBA during production implementation, in this embodiment, the conditioning chip and each electronic component are changed to be disposed on the third circuit board 16 (FPC) on the basis of implementation 1 to implementation 2, and the integral bracket 24 is used for supporting, so that the second half-package bracket 19 is omitted, the space is optimized on the premise of ensuring the integrity, and the assembly efficiency is greatly improved.

Example 4

In the method for reducing the diameter of the high-pressure sensor of the present invention, this example 4 includes all or at least some of the embodiments of examples 1 and 2, in which the same points are not described in detail, the difference is that:

the two circuit boards of the first circuit board 10 and the second circuit board 15 which are arranged in parallel are used for increasing the wire binding area, and the first circuit board 10 and the second circuit board 15 are electrically connected through the third circuit board 16, so that the wire binding area equivalent to the large-size high-pressure sensor is obtained through accumulation of at least two circuit boards which are arranged in parallel on the basis of small size; to increase the pad space of the PCBA (i.e. increase the utilization of space) and reduce the overall size of the high-pressure sensor.

Example 5

The small diameter high pressure sensor and method of the present invention, example 5 includes all or at least some of the embodiments of examples 1 to 4, wherein the same points are not repeated, except that: the spring seat 8 and the spring cover 12 are combined into a whole structure, and the snake pin 9 is installed from the lower part of the connecting hole 11 when the spring seat is installed.

The terms first, second and the like in the description and in the claims, are not used for any order, quantity or importance, but are used for distinguishing between different elements. Likewise, the terms "a," "an," or "the" and similar terms do not denote a limitation of quantity, but rather denote the presence of at least one. The word "comprising" or "comprises", and the like, is intended to mean that elements or items that are present in front of "comprising" or "comprising" are included in the word "comprising" or "comprising", and equivalents thereof, without excluding other elements or items. "upper", "lower", "left", "right", etc. are used merely to indicate relative positional relationships, which may also be changed when the absolute position of the object to be described is changed.

The preferred embodiments of the present invention described above are not intended to limit the present invention, and the scope of the present invention is defined by the appended claims, and other embodiments can be obtained from the drawings without inventive faculty to those skilled in the art, and any modifications based on the claims of the present invention are also the scope of the present invention.

Claims

1. A small diameter high pressure sensor, comprising:

the strain gauge is arranged on the pressure sensing film;

a snake pin needle fixedly mounted on the spring seat;

A first circuit board mounted in the housing at a horizontal angle, the first circuit board being between the strain gauge and the spring seat; the first circuit board is electrically connected with the strain gauge and the snake pin needle respectively;

the second circuit board is positioned in the shell and between the first circuit board and the spring seat; the second circuit board is arranged in parallel with the first circuit board;

2. The small diameter high pressure sensor of claim 1, wherein the snake pin needle is a spring; the outer diameter of at least the lower part of the snake pin needle is larger than that of the upper Fang Waijing.

3. The small diameter high pressure sensor of claim 2, wherein the spring seat has a connecting hole; the lower end part of the snake pin needle is arranged in the connecting hole;

4. A small diameter high pressure sensor according to claim 3, wherein the end of the housing to which the spring cover is attached has an annular inner rim that abuts the upper rim of the spring cover.

5. The small diameter high pressure sensor of claim 1, comprising a first half-pack bracket at least partially abutting an outer wall of the pressure sensing body and fixedly connected thereto; a fixed integrated placing table is arranged at the upper end part of the first half bag bracket; the horizontal height of the placing table is higher than that of the strain gauge, and the placing table and the strain gauge are in parallel height; the first circuit board is mounted on the placing table.

6. The small diameter high pressure sensor of claim 5, comprising a second half-pack bracket at least partially abutting an outer wall of the pressure sensing body; one end of the second half-package support is fixedly connected with the pressure sensing main body, and the other end of the second half-package support is abutted to the lower portion of the second circuit board.

7. The small-diameter high-pressure sensor according to claim 6, wherein a side surface of the first half-package support, which is abutted against the second half-package support, is provided with a first limit notch at a horizontal angle;

8. The small diameter high pressure sensor of claim 1, wherein the first and second circuit boards are PCBs; the third circuit board is an FPC.

9. The manufacturing method of the small-diameter high-pressure sensor is characterized in that a pressure sensing main body with an integrated structure is adopted, one end of the pressure sensing main body is a connecting end, and the other end of the pressure sensing main body is a pressed surface;

Sand blasting is carried out on the pressed surface;

cleaning the pressure sensing main body;

aging the pressure sensing main body after the steps are completed;

welding a first half-pack bracket to the pressure sensing body;

a second circuit board is fixed through a second half-package bracket;

assembling the pressure sensing main body, the first half-package support, the first circuit board, the second half-package support, the spring seat, the spring cover and the snake pin needle in a shell, welding the pressure sensing main body and the lower end part of the shell, and sealing the spring cover and the upper end part of the shell;

and testing the product and warehousing.

10. The manufacturing method of the small-diameter high-pressure sensor is characterized in that a pressure sensing main body with an integrated structure is adopted, one end of the pressure sensing main body is a connecting end, and the other end of the pressure sensing main body is a pressed surface;

sand blasting is carried out on the pressed surface;

cleaning the pressure sensing main body;

Aging the pressure sensing main body after the steps are completed;

welding a first half-pack bracket to the pressure sensing body;

adding an integral bracket in the shell, wherein the upper end part of the integral bracket is provided with a second through hole which is gradually smaller from bottom to top; wherein the external diameter of the snake pin needle is matched with the second through hole; the snake pin is fixedly connected in the second through hole and is electrically connected with a third circuit board in the second through hole;

and testing the product and warehousing.

11. The diameter reduction method of the high pressure sensor is characterized in that a pressure sensing main body with an integrated structure is adopted, one end of the pressure sensing main body is a connecting end, and the other end of the pressure sensing main body is a pressed surface;

sand blasting is carried out on the pressed surface;

cleaning the pressure sensing main body;

aging the pressure sensing main body after the steps are completed;

welding a first half-pack bracket to the pressure sensing body;

arranging a first circuit board and a second circuit board for increasing the binding wire area; the first circuit board and the second circuit board are respectively and horizontally arranged and are in parallel angles; the first circuit board is electrically connected with the second circuit board through a third circuit board which is vertically arranged, so that the pad space of the PCBA is increased, and the overall size of the high-pressure sensor is reduced;

a second circuit board is fixed through a second half-package bracket;

and testing the product and warehousing.