Small-diameter pressure sensor

Abstract

The invention relates to the technical field of sensors, in particular to a small-diameter pressure sensor which comprises an induction base, a ceramic pressure induction module is arranged on the induction base, a placement groove used for containing the ceramic pressure induction module is formed in the induction base, and a pressure flow channel communicated with the placement groove is formed in the outer portion of the induction base. A sealing piece used for sealing is arranged between the ceramic pressure sensing module and the sensing base, a pressing ring is arranged on the sensing base and used for pressing the ceramic pressure sensing module on the sensing base, an upper end shell with the hollow interior and an opening facing one side of the pressing ring is arranged on the pressing ring, and a support is arranged in the upper end shell. The support is provided with a fixing piece used for fixing the upper end shell to the pressing ring, the support is provided with a processing circuit board, the processing circuit board is electrically connected with a lower elastic piece, and the upper end shell is provided with a signal transmission piece used for transmitting electric signals on the processing circuit board. The pressure sensor has the effect of reducing the production cost of the pressure sensor.

Description

Technical Field

[0001] This application relates to the field of sensor technology, and in particular to a small-diameter pressure sensor. Background Technology

[0002] The brake pressure sensor is an important electrical component in the automotive braking system. A pressure sensor is a device that detects pressure through a pressure-sensitive element and converts it into a measurable electrical signal. Its core principles include the piezoelectric effect (some materials generate charge when compressed) and the piezoresistive effect (material deformation causes a change in resistance).

[0003] Currently, pressure sensors used in automotive braking systems have limited installation space, and because they are high-pressure products, they are constantly subjected to high pressure and high temperature during use due to the limited space in both the horizontal and vertical directions.

[0004] Chinese Patent No. CN115979497B discloses a small-diameter high-pressure sensor, comprising a first circuit board mounted horizontally within a housing, positioned between a strain gauge and a spring seat; the first circuit board is electrically connected to both the strain gauge and the snake pin; and a second circuit board is located within the housing and between the first circuit board and the spring seat; the second circuit board is arranged parallel to the first circuit board.

[0005] In the above-mentioned technology, the first and second circuit boards are electrically connected by wire bonding. However, in actual production, because the pressure sensor itself is very small and the wire bonding is usually very thin, it is difficult to ensure the structural strength of the wire bonding during the process of bonding the first and second circuit boards (which easily leads to poor soldering). On the other hand, the wire bonding is easily melted, which results in a higher cost for the pressure sensor produced.

[0006] Chinese Patent No. CN219416503U discloses a pressure sensor signal processing component, including a horizontal plate, a first flexible plate, a vertical plate, a second flexible plate, and a first conductive connection part connected in sequence, with the horizontal plate, vertical plate, and first conductive connection part arranged from near to far; the first conductive connection part is connected to a pressure measuring circuit, which is disposed on a horizontal plane located on the far side of the first conductive connection part.

[0007] In the aforementioned technology, the flexible plate is fixed by a riveting post, which avoids the problem of welding. However, since the sensor itself is small and the flexible plate is located inside the sensor, the volume of the flexible plate is even smaller. On the one hand, the flexible plate is easily damaged by excessive pressure and easily loosens by insufficient pressure. On the other hand, the small size of the flexible plate makes it difficult to fix, which can easily lead to skew during the fixing process, resulting in substandard sensor quality. Therefore, in actual production, the fixing process of the flexible plate greatly increases the difficulty of overall sensor assembly, which in turn leads to higher cost of the pressure sensor and has its shortcomings. Summary of the Invention

[0008] To address the issue of high cost of pressure sensors in the aforementioned technologies, this application provides a small-diameter pressure sensor.

[0009] The small-diameter pressure sensor provided in this application adopts the following technical solution: A small-diameter pressure sensor includes a sensing base, on which a ceramic pressure sensing module is disposed. The sensing base has a mounting groove for accommodating the ceramic pressure sensing module. A pressure flow channel communicating with the mounting groove is formed on the outside of the sensing base. A sealing element is provided between the ceramic pressure sensing module and the sensing base for sealing. A pressure ring is provided on the sensing base to press the ceramic pressure sensing module firmly against the sensing base. The pressure ring has a hollow upper shell that is open to one side of the pressure ring. A bracket is disposed inside the upper shell. A fixing element for fixing the upper shell to the pressure ring is provided on the bracket. A processing circuit board is disposed on the bracket. A lower spring is electrically connected to the processing circuit board. When the pressure ring is pressed against the ceramic pressure sensing module, the lower spring passes through the inner diameter of the pressure ring and presses against the ceramic pressure sensing module. A signal transmission element for transmitting electrical signals from the processing circuit board is provided on the upper shell.

[0010] By adopting the above technical solution, workers first install the processing circuit board on the bracket, and then install the bracket inside the upper shell, thereby reducing the diameter of the pressure sensor. The upper shell and the pressure ring are fixed to the bracket by fasteners. Then, the pressure ring is pressed onto the ceramic pressure sensing module on the sensing base. Subsequently, the pressure ring and the sensing base are fixed by laser welding. At this time, the lower spring sheet abuts and presses against the ceramic pressure sensing module through deformation, realizing signal transmission between the ceramic pressure sensing module and the processing circuit board, avoiding a series of problems caused by traditional wire bonding and welding. The sealing component can ensure the accuracy of the pressure value measured by the ceramic pressure sensing module through the pressure channel. Finally, the signal transmission component transmits the electrical signal on the processing circuit board to the external connection device. The pressure ring presses against the ceramic pressure sensing module, thereby further reducing the diameter of the pressure sensor. Since the pressure sensor is assembled by modular assembly, the overall quality of the produced pressure sensor is controllable, and the assembly difficulty is low, so the production cost can be greatly reduced.

[0011] Optionally, the sealing element includes an annular rubber ring disposed between the ceramic pressure sensing module and the sensing base, and the sensing base has a rubber groove for accommodating the annular rubber ring.

[0012] By adopting the above technical solution, the annular rubber ring achieves sealing at the pressure flow channel through deformation, ensuring the accuracy of the measurement signal of the ceramic pressure sensing module.

[0013] Optionally, the fixing component includes a fixing block disposed on the bracket, a fixing strip disposed on the fixing block, a shell locking block disposed on the top of the fixing strip, a shell locking groove for the shell locking block to engage between the inner and outer walls of the upper shell, a ring locking block disposed at the bottom of the fixing strip, and a ring locking groove for the ring locking block to engage between the inner and outer walls of the pressure ring. When the upper shell is fixed on the pressure ring, the lower surface of the shell locking block abuts against the shell locking groove, and the upper surface of the ring locking block abuts against the ring locking groove.

[0014] By adopting the above technical solution, after the circuit board is fixed on the bracket, the worker puts the upper shell on the top of the bracket and the pressure ring on the bottom of the bracket. During this process, the fixing strip will deform because the shell locking block abuts against the inner wall of the upper shell and the ring locking block abuts against the inner wall of the pressure ring, until the upper shell abuts against the pressure ring. At this time, the fixing strip will return to its original shape, and at the same time, the lower surface of the shell locking block will abut against the shell locking groove and the upper surface of the ring locking block will abut against the ring locking groove, thereby realizing the rapid assembly and fixing between the upper shell and the pressure ring.

[0015] Optionally, the signal transmission device includes a plurality of spring pins disposed on the upper end shell, the spring pins being electrically connected to the processing circuit board, and a plurality of pin holes for the spring pins to pass through are provided between the inner and outer walls of the upper end shell, the pin holes corresponding one-to-one with the spring pins.

[0016] By adopting the above technical solution, the spring pin helps the pressure sensor maintain a stable delivery effect during vehicle operation.

[0017] Optionally, a horizontal transfer circuit board is provided between the bracket and the upper shell. The transfer circuit board has multiple electrical contact protrusions integrally formed on it. The spring pins abut against the electrical contact protrusions, and the electrical contact protrusions correspond one-to-one with the spring pins. The inner sidewall of the upper shell is provided with a mounting guide groove for the electrical contact protrusions to slide into. An upper spring is electrically connected to the processing circuit board. The upper spring abuts against and presses against the transfer circuit board. The upper spring is used to electrically connect the processing circuit board and the transfer circuit board.

[0018] By adopting the above technical solution, before assembling the bracket, the worker first inserts the spring pin into the pin hole from the inside of the upper shell. Then, the transfer circuit board is installed in the upper shell through the installation guide groove. During the process of the upper shell being fitted onto the bracket, the upper spring piece will first abut against the transfer circuit board until the lower surface of the shell clip abuts against the shell clip groove. During this process, the upper spring piece will deform. By setting a separate horizontal transfer circuit board, the length dimension of the pressure sensor is shortened. Moreover, since the upper and lower spring pieces can deform, the length dimension of the pressure sensor can be further shortened.

[0019] Optionally, a mounting plate is inserted into one end of the bracket facing the upper shell, the transfer circuit board is located between the upper shell and the mounting plate, the processing circuit board is disposed on the mounting plate, and the bracket is provided with a slot for the mounting plate to be inserted.

[0020] By adopting the above technical solution, workers can first insert the mounting plate into the slot on the bracket to complete the assembly between the processing circuit board and the bracket. The transfer circuit board and the upper shell will prevent the mounting plate from detaching from the bracket, thereby further reducing the difficulty for workers to assemble the processing circuit board on the bracket.

[0021] Optionally, the bracket is provided with a limiting block, and the pressure ring is provided with a limiting groove for the limiting block to be inserted.

[0022] By adopting the above technical solution, the difficulty for workers in assembling the pressure ring and the bracket is reduced.

[0023] Optionally, a shell guide slope is provided on the side of the shell block facing away from the fixing block, and the shell guide slope is inclined away from the fixing block along the direction from the shell block to the fixing strip. A ring guide slope is provided on the side of the ring block facing away from the fixing block, and the ring guide slope is inclined away from the fixing block along the direction from the ring block to the fixing strip.

[0024] By adopting the above technical solution, the difficulty of fitting the pressure ring and the upper shell onto the bracket is reduced, which helps to improve the assembly efficiency of workers.

[0025] Optionally, the bracket is provided with a tension slot, and a tension spring is provided in the tension slot. One end of the tension spring abuts against the transfer circuit board, and the other end abuts against the pressure ring.

[0026] By adopting the above technical solution, the transfer circuit board is fixed, reducing the possibility of the transfer circuit board shaking due to the dimensional errors of some components during the production process, which is conducive to improving the stability of the spring pin output signal.

[0027] In summary, this application includes at least one of the following beneficial technical effects: 1. Workers first install the vertical processing circuit board on the bracket using positioning components, thereby reducing the diameter of the pressure sensor. The upper shell and pressure ring are then fixed to the bracket using positioning components. Next, the pressure ring is pressed onto the ceramic pressure sensing module on the sensing base. Subsequently, the pressure ring is fixed to the sensing base using laser welding. At this point, the lower spring sheet deforms and presses against the ceramic pressure sensing module, enabling signal transmission between the ceramic pressure sensing module and the processing circuit board. This avoids a series of problems caused by traditional wire bonding and welding. The sealing component ensures the accuracy of the pressure value measured by the ceramic pressure sensing module through the pressure channel. At the same time, the spring pin can output the signal measured by the ceramic pressure sensing module in a timely manner, and the pressure ring presses against the ceramic pressure sensing module, thereby further reducing the diameter of the pressure sensor. Because the pressure sensor is assembled using a modular assembly method, the overall quality of the produced pressure sensor is controllable, and the assembly difficulty is low, thus greatly reducing production costs. 2. After the circuit board is fixed on the bracket, the worker inserts the upper shell from the top of the bracket and the pressure ring from the bottom of the bracket. During this process, the fixing strip will deform because the shell locking block abuts against the inner wall of the upper shell and the ring locking block abuts against the inner wall of the pressure ring, until the upper shell abuts against the pressure ring. At this time, the fixing strip will return to its original shape, and at the same time, the lower surface of the shell locking block will abut against the shell locking groove and the upper surface of the ring locking block will abut against the ring locking groove, thereby realizing the quick assembly and fixation between the upper shell and the pressure ring. 3. Before assembling the bracket, the worker first inserts the spring pin into the pin hole from the inside of the upper shell. Then, the transfer circuit board is installed inside the upper shell through the installation guide groove. During the process of the upper shell being fitted onto the bracket, the upper spring piece will first abut against the transfer circuit board until the lower surface of the shell clip abuts against the shell clip groove. During this process, the upper spring piece will deform. By setting up a separate horizontal transfer circuit board, the length dimension of the pressure sensor is shortened. Moreover, since the upper and lower spring pieces can deform, the length dimension of the pressure sensor can be further shortened. Attached Figure Description

[0028] Figure 1 This is a structural schematic diagram of an embodiment of this application.

[0029] Figure 2 This is a cross-sectional view used in the embodiments of this application to illustrate the positional relationship between the ceramic pressure sensing module, the lower spring, and the upper spring.

[0030] Figure 3 This is an explosion diagram from an embodiment of this application.

[0031] Figure 4 This is a structural schematic diagram in the embodiments of this application used to illustrate the positional relationship between the upper shell and the spring pin.

[0032] Figure 5 This is a structural schematic diagram illustrating the positional relationship between the upper shell and the metal pin in an embodiment of this application. Explanation of reference numerals in the attached drawings: 1. Sensing base; 2. Ceramic pressure sensing module; 3. Mounting groove; 4. Pressure flow channel; 5. Seal; 51. Annular rubber ring; 52. Rubber groove; 6. Pressure ring; 7. Upper shell; 8. Bracket; 9. Fixing component; 91. Fixing block; 92. Fixing strip; 93. Shell retaining block; 94. Shell retaining groove; 95. Ring retaining block; 96. Ring retaining groove; 10. Processing circuit board; 11. Lower spring; 12. Signal transmission component; 21. Spring pin; 122. Pinhole; 13. Transfer circuit board; 14. Electrical contact protrusion; 15. Mounting guide groove; 16. Upper spring sheet; 17. Mounting plate; 18. Insertion plate groove; 19. Limiting block; 20. Limiting groove; 21. Shell guide slope; 22. Ring guide slope; 23. Tension groove hole; 24. Tension spring; 25. Positioning pin; 26. Pin groove; 27. Stepped groove; 28. Metal pin; 29. ​​Clearance hole. Detailed Implementation

[0033] The following is in conjunction with the appendix Figures 1-5 This application will be described in further detail.

[0034] This application discloses a small-diameter pressure sensor.

[0035] Reference Figure 1 and Figure 2 A small-diameter pressure sensor includes a sensing base 1, a ceramic pressure sensing module 2 arranged on the sensing base 1, a mounting groove 3 for accommodating the ceramic pressure sensing module 2 on the top of the sensing base 1, a positioning pin 25 inserted into the sensing base 1, a pin groove 26 for avoiding the positioning pin 25 on the ceramic pressure sensing module 2, and a pressure flow channel 4 vertically formed at the bottom of the sensing base 1, communicating with the mounting groove 3.

[0036] Reference Figure 2 and Figure 3 A sealing element 5 is arranged between the ceramic pressure sensing module 2 and the sensing base 1 for sealing. The sealing element 5 includes an annular rubber ring 51 arranged between the ceramic pressure sensing module 2 and the sensing base 1. The annular rubber ring 51 can be made of heat-resistant rubber material in the prior art. A rubber groove 52 is opened on the sensing base 1 for accommodating the annular rubber ring 51. The rubber groove 52 is connected to the mounting groove 3.

[0037] Reference Figure 2 A pressure ring 6 is laser-welded onto the sensing base 1. A stepped groove 27 is provided on the pressure ring 6 for the sensing base 1 to be fitted. The bottom of the pressure ring 6 presses the ceramic pressure sensing module 2 onto the annular rubber ring 51 on the sensing base 1. An upper shell 7 with a hollow interior and an opening facing one side of the pressure ring 6 is arranged on the pressure ring 6. A bracket 8 is inserted into the upper shell 7. A limit block 19 is integrally formed at the bottom of the bracket 8. A limit groove 20 is provided on the upper surface of the pressure ring 6 for the limit block 19 to be inserted.

[0038] The worker first places the annular rubber ring 51 into the rubber groove 52 on the sensing base 1, then places the ceramic pressure sensing module 2 into the mounting groove 3, then inserts the bottom of the pressure ring 6 into the sensing base 1, and then fixes the pressure ring 6 and the sensing base 1 with a special clamping device. Finally, the pressure ring 6 and the sensing base 1 are welded and fixed by a laser welding machine.

[0039] Reference Figure 2 and Figure 3 A vertical processing circuit board 10 is arranged on the bracket 8. The bottom of the processing circuit board 10 is electrically connected to a lower spring 11. The lower spring 11 can be made of an elastic metal material with good conductivity. When the pressure ring 6 is pressed on the ceramic pressure sensing module 2, the lower spring 11 passes through the inner diameter of the pressure ring 6 and is pressed on the ceramic pressure sensing module 2.

[0040] Reference Figure 2 and Figure 3The upper end shell 7 is provided with a signal transmission component 12 for transmitting electrical signals on the processing circuit board 10. The signal transmission component 12 includes three spring pins 121 arranged on the upper end shell 7. The spring pins 121 are electrically connected to the processing circuit board 10. Three pin holes 122 are opened between the inner and outer walls of the upper end shell 7 for the spring pins 121 to pass through. The pin holes 122 correspond one-to-one with the spring pins 121.

[0041] Reference Figure 2 and Figure 3 The inner diameter of the pinhole 122 gradually decreases along the direction from the pressure ring 6 to the upper shell 7. The spiral diameter of the middle part of the spring pin 121 is larger than the spiral diameter at both ends. The minimum inner diameter of the pinhole 122 is smaller than the spiral diameter of the middle part of the spring pin 121. The distance from the lower end face of the sensing base 1 to the upper end face of the upper shell 7 is 11mm. The signal transmission element 12 can also be a metal spring sheet as used in the prior art.

[0042] Reference Figure 2 and Figure 3 The bracket 8 is provided with a fixing member 9 for fixing the upper shell 7 to the pressure ring 6. The fixing member 9 includes a fixing block 91 integrally formed on the bracket 8, a fixing strip 92 integrally formed on the fixing block 91, a shell locking block 93 integrally formed on the top of the fixing strip 92, and a shell locking groove 94 for the shell locking block 93 to engage between the inner and outer walls of the upper shell 7.

[0043] Reference Figure 2 and Figure 3 The bottom of the fixing strip 92 is integrally formed with a ring retainer 95. A ring retainer groove 96 is provided between the inner and outer walls of the pressure ring 6 for the ring retainer 95 to engage. When the upper shell 7 is fixed on the pressure ring 6, the lower surface of the shell retainer 93 abuts against the shell retainer groove 94, and the upper surface of the ring retainer 95 abuts against the ring retainer groove 96.

[0044] Reference Figure 2 A shell guide slope 21 is provided on the side of the shell block 93 facing away from the fixing block 91. The shell guide slope 21 is inclined away from the fixing block 91 along the direction from the shell block 93 to the fixing strip 92. A ring guide slope 22 is provided on the side of the ring block 95 facing away from the fixing block 91. The ring guide slope 22 is inclined away from the fixing block 91 along the direction from the ring block 95 to the fixing strip 92.

[0045] Reference Figure 2 and Figure 3 A horizontal transfer circuit board 13 is arranged between the bracket 8 and the upper shell 7. Three electrical contact protrusions 14 are integrally formed on the transfer circuit board 13. The bottom of the spring pin 121 abuts against the electrical contact protrusions 14. The electrical contact protrusions 14 and the spring pin 121 correspond one-to-one.

[0046] Reference Figure 2 , Figure 3 and Figure 4 The inner wall of the upper shell 7 has three power supply contact protrusions 14 that slide into the mounting guide grooves 15. The mounting guide grooves 15 correspond one-to-one with the power contact protrusions 14. The processing circuit board 10 is electrically connected to an upper spring piece 16. The upper spring piece 16 can be made of a flexible metal material with good conductivity. The upper spring piece 16 abuts against and presses against the bottom of the transfer circuit board 13. The upper spring piece 16 is used to electrically connect the processing circuit board 10 and the transfer circuit board 13.

[0047] Reference Figure 2 and Figure 3 The bracket 8 has a tension slot 23, and a tension spring 24 passes through the tension slot 23. One end of the tension spring 24 abuts against the bottom of the transfer circuit board 13, and the other end abuts against the upper surface of the pressure ring 6. A mounting plate 17 is inserted into the end of the bracket 8 facing the upper shell 7. The transfer circuit board 13 is located between the upper shell 7 and the mounting plate 17. The processing circuit board 10 is bolted to the mounting plate 17. The bracket 8 has a slot 18 for inserting the mounting plate 17.

[0048] Reference Figure 5 The signal transmission component 12 can also use the metal pin 28 in the prior art, and a clearance hole 29 is opened between the inner and outer walls of the top of the upper housing 7 for the metal pin 28 to pass through.

[0049] The workers first install the spring pin 121 into the pin hole 122 from the inside of the upper shell 7. Then, the transfer circuit board 13 is installed inside the upper shell 7 through the installation guide groove 15. At the same time, another group of workers inserts the mounting plate 17, which fixes the processing circuit board 10, into the insertion slot 18 of the bracket 8.

[0050] Then, the worker inserts the assembled bracket 8 into the upper shell 7. During this process, the shell guide slope 21 on the shell block 93 will first abut against the opening edge of the upper shell 7. As the bracket 8 is continuously inserted, the fixing strip 92 will deform under the action of the shell guide slope 21.

[0051] Until the lower surface of the housing block 93 abuts against the housing slot 94, the fixing strip 92 resumes its deformation. During this process, the upper spring piece 16 abuts against the bottom of the transfer circuit board 13, and at the same time, the upper spring piece 16 will undergo a certain deformation.

[0052] The worker places the tension spring 24 into the tension slot 23. Then, based on the relationship between the limiting block 19 and the limiting slot 20, the worker puts the pressure ring 6 on the other end of the bracket 8. As the pressure ring 6 is continuously put in, the ring guide slope 22 on the ring clamp 95 will first abut against the edge of the pressure ring 6. As the ring clamp 95 is continuously put into the bracket 8, the fixing strip 92 will deform under the action of the ring guide slope 22.

[0053] Until the upper surface of the ring block 95 abuts against the ring groove 96, the fixing strip 92 resumes its deformation, and the pressure ring 6 abuts against the upper shell 7. During this process, the lower spring 11 passes through the inner diameter of the pressure ring 6 and abuts against the ceramic pressure sensing module 2, while the lower spring 11 undergoes a certain deformation.

[0054] While transmitting pressure signals through the upper spring 16 and the lower spring 11, the diameter and length of the pressure sensor have been reduced. Moreover, the modular assembly method greatly reduces the difficulty of assembly during the entire assembly process of the pressure sensor. At the same time, the quality of each component can be controlled, thereby reducing production costs.

[0055] The implementation principle of a small-diameter pressure sensor in this application embodiment is as follows: the worker first places the annular rubber ring 51 in the rubber groove 52 on the sensing base 1, then places the ceramic pressure sensing module 2 in the mounting groove 3, then inserts the bottom of the pressure ring 6 into the sensing base 1, and then fixes the pressure ring 6 and the sensing base 1 by a special clamping device. Subsequently, the pressure ring 6 and the sensing base 1 are welded and fixed by a laser welding machine.

[0056] The workers first install the spring pin 121 into the pin hole 122 from the inside of the upper shell 7. Then, the transfer circuit board 13 is installed inside the upper shell 7 through the installation guide groove 15. At the same time, another group of workers inserts the mounting plate 17, which fixes the processing circuit board 10, into the insertion slot 18 of the bracket 8.

[0057] Then, the worker inserts the assembled bracket 8 into the upper shell 7. During this process, the shell guide slope 21 on the shell block 93 will first abut against the opening edge of the upper shell 7. As the bracket 8 is continuously inserted, the fixing strip 92 will deform under the action of the shell guide slope 21.

[0058] Until the lower surface of the housing block 93 abuts against the housing slot 94, the fixing strip 92 resumes its deformation. During this process, the upper spring piece 16 abuts against the bottom of the transfer circuit board 13, and at the same time, the upper spring piece 16 will undergo a certain deformation.

[0059] The worker places the tension spring 24 into the tension slot 23. Then, based on the relationship between the limiting block 19 and the limiting slot 20, the worker puts the pressure ring 6 on the other end of the bracket 8. As the pressure ring 6 is continuously put in, the ring guide slope 22 on the ring clamp 95 will first abut against the edge of the pressure ring 6. As the ring clamp 95 is continuously put into the bracket 8, the fixing strip 92 will deform under the action of the ring guide slope 22.

[0060] Until the upper surface of the ring block 95 abuts against the ring groove 96, the fixing strip 92 resumes its deformation, and the pressure ring 6 abuts against the upper shell 7. During this process, the lower spring 11 passes through the inner diameter of the pressure ring 6 and abuts against the ceramic pressure sensing module 2, while the lower spring 11 undergoes a certain deformation.

[0061] While transmitting pressure signals through the upper spring 16 and the lower spring 11, the diameter and length of the pressure sensor have been reduced. Moreover, the modular assembly method greatly reduces the difficulty of assembly during the entire assembly process of the pressure sensor. At the same time, the quality of each component can be controlled, thereby reducing production costs.

[0062] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A small-diameter pressure sensor, characterized in that: The system includes a sensing base (1), on which a ceramic pressure sensing module (2) is arranged. The sensing base (1) has a mounting groove (3) for accommodating the ceramic pressure sensing module (2). A pressure flow channel (4) communicating with the mounting groove (3) is provided on the outside of the sensing base (1). A sealing element (5) for sealing is provided between the ceramic pressure sensing module (2) and the sensing base (1). A pressure ring (6) is provided on the sensing base (1) to press the ceramic pressure sensing module (2) tightly onto the sensing base (1). The pressure ring (6) has an internally hollow part facing the pressure ring (1). 6) An upper shell (7) with an open side, a bracket (8) is provided inside the upper shell (7), a fixing member (9) for fixing the upper shell (7) on the pressure ring (6) is provided on the bracket (8), a processing circuit board (10) is provided on the bracket (8), a lower spring piece (11) is electrically connected to the processing circuit board (10), when the pressure ring (6) is pressed on the ceramic pressure sensing module (2), the lower spring piece (11) passes through the inner diameter of the pressure ring (6) and is pressed on the ceramic pressure sensing module (2), and a signal transmission member (12) for transmitting electrical signals on the processing circuit board (10) is provided on the upper shell (7).

2. The small-diameter pressure sensor according to claim 1, characterized in that: The sealing element (5) includes an annular rubber ring (51) disposed between the ceramic pressure sensing module (2) and the sensing base (1), and the sensing base (1) has a rubber groove (52) for accommodating the annular rubber ring (51).

3. A small-diameter pressure sensor according to claim 1, characterized in that: The fixing member (9) includes a fixing block (91) disposed on the bracket (8), a fixing strip (92) disposed on the fixing block (91), a shell locking block (93) disposed on the top of the fixing strip (92), a shell locking groove (94) for the shell locking block (93) to engage is provided between the inner and outer walls of the upper shell (7), a ring locking block (95) disposed at the bottom of the fixing strip (92), and a ring locking groove (96) for the ring locking block (95) to engage is provided between the inner and outer walls of the pressure ring (6). When the upper shell (7) is fixed on the pressure ring (6), the lower surface of the shell locking block (93) abuts against the shell locking groove (94), and the upper surface of the ring locking block (95) abuts against the ring locking groove (96).

4. A small-diameter pressure sensor according to claim 3, characterized in that: The signal transmission component (12) includes a plurality of spring pins (121) disposed on the upper end shell (7). The spring pins (121) are electrically connected to the processing circuit board (10). A plurality of pin holes (122) are provided between the inner and outer walls of the upper end shell (7) for the spring pins (121) to pass through. The pin holes (122) correspond one-to-one with the spring pins (121).

5. A small-diameter pressure sensor according to claim 4, characterized in that: A horizontal transfer circuit board (13) is provided between the bracket (8) and the upper shell (7). Multiple electrical contact protrusions (14) are integrally formed on the transfer circuit board (13). The spring pin (121) abuts against the electrical contact protrusions (14). The electrical contact protrusions (14) and the spring pin (121) correspond one-to-one. An installation guide groove (15) is provided on the inner side wall of the upper shell (7) for the electrical contact protrusions (14) to slide into. An upper spring piece (16) is electrically connected to the processing circuit board (10). The upper spring piece (16) abuts against and presses against the transfer circuit board (13). The upper spring piece (16) is used to electrically connect the processing circuit board (10) and the transfer circuit board (13).

6. A small-diameter pressure sensor according to claim 5, characterized in that: The bracket (8) has a mounting plate (17) inserted into one end facing the upper shell (7). The transfer circuit board (13) is located between the upper shell (7) and the mounting plate (17). The processing circuit board (10) is disposed on the mounting plate (17). The bracket (8) has a slot (18) for the mounting plate (17) to be inserted.

7. A small-diameter pressure sensor according to claim 1, characterized in that: The bracket (8) is provided with a limiting block (19), and the pressure ring (6) is provided with a limiting groove (20) for the limiting block (19) to be inserted.

8. A small-diameter pressure sensor according to claim 3, characterized in that: A shell guide slope (21) is provided on the side of the shell clamping block (93) facing away from the fixing block (91). The shell guide slope (21) is inclined away from the fixing block (91) along the direction from the shell clamping block (93) to the fixing strip (92). A ring guide slope (22) is provided on the side of the ring clamping block (95) facing away from the fixing block (91). The ring guide slope (22) is inclined away from the fixing block (91) along the direction from the ring clamping block (95) to the fixing strip (92).

9. A small-diameter pressure sensor according to claim 5, characterized in that: The bracket (8) has a tension slot (23) and a tension spring (24) is provided in the tension slot (23). One end of the tension spring (24) abuts against the transfer circuit board (13) and the other end abuts against the pressure ring (6).

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