A pressure sensor overload protection module
By introducing a limiting module and a precisely machined limiting post into the pressure sensor, the problem of easy damage to the diaphragm in existing devices is solved, achieving effective protection of the diaphragm and improving the reliability and accuracy of the sensor.
Patent Information
- Application Number
- CN202522806522.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-30
- Publication Date
- 2026-11-06
- Estimated Expiration
- 2035-12-30
AI Technical Summary
Existing pressure sensor overload protection devices lack limiting structures, making the sensing diaphragm prone to damage under overload conditions.
An overload protection module for a pressure sensor was designed, including a limiting module. The limiting post limits the maximum pressure that the diaphragm inside the diaphragm pressure sensor can withstand. The limiting post is integrally formed with the shell and the accuracy of the limiting post is ensured by milling and copper electrode discharge etching to prevent the pressure ring from tilting.
It effectively protects the sensing film from overload damage, ensuring the reliability and accuracy of the sensor.
Smart Images
Figure CN224945574U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of sensor technology, and in particular to an overload protection module for a pressure sensor. Background Technology
[0002] A pressure sensor is a device that can sense the pressure information being measured and convert the sensed pressure information into an electrical signal or other required form of information output according to a certain rule. Pressure sensors have a certain range. During the application of pressure load, if the load exceeds the range of the pressure sensor, it will cause irreversible deformation of the internal elasticity of the pressure sensor. Therefore, an overload protection device is needed. However, existing overload protection devices do not have a limiting structure, which can easily lead to damage to the sensing diaphragm. Utility Model Content
[0003] The purpose of this invention is to provide a pressure sensor overload protection module to solve the problems existing in the prior art.
[0004] The above-mentioned technical objective of this utility model is achieved through the following technical solution: An overload protection module for a pressure sensor includes a thin-film pressure sensor and a limiting module disposed inside the thin-film pressure sensor. The limiting module is used to limit the maximum pressure that the thin-film pressure sensor can withstand. The thin-film pressure sensor includes a housing, a sensing diaphragm installed inside the housing, and a pressure ring slidably installed inside the housing. The pressure ring is used to compress the periphery of the sensing diaphragm, causing the sensing diaphragm to deform. An annular protrusion is provided in the middle section of the inner side of the housing. The bottom of the sensing diaphragm is in contact with the top of the annular protrusion, and the bottom of the pressure ring is in contact with the top periphery of the sensing diaphragm. A plurality of protrusions are axially and evenly arranged on the periphery of the pressure ring. The bottom end face of the protrusion is not coplanar with the bottom end face of the pressure ring, and the top end face of the protrusion is coplanar with the top end face of the pressure ring. The inner side of the housing is provided with a sliding groove corresponding to each protrusion. The length direction of the sliding groove is vertical, and a limiting post is installed at the bottom of each sliding groove.
[0005] By adopting the above technical solution, the limiting post is an important component of the limiting module of this application. When the bottom of the protrusion on the periphery of the pressure ring contacts the top of the limiting post, the pressure ring cannot continue to move down. In order to ensure the flatness of the top of the limiting post and avoid the pressure ring from tilting, the best way is to integrally form the limiting post with the shell. The top of the support post is quickly milled to a certain value using a milling cutter, and then the end face of the support post is etched out by electrical discharge etching. Generally, etching is done by discharging copper electrodes. The flatness accuracy of the bottom of the copper electrode is the flatness accuracy of the top of the support post. Because the bottom of the copper electrode is open, it can be ground flat by a grinding machine. However, the top of the support post is recessed inside the shell, so this is not possible. The copper electrode discharge etching method can completely ensure the top accuracy of multiple limiting posts.
[0006] In a further embodiment, the top of the limiting post is higher than the top height of the annular protrusion.
[0007] By adopting the above technical solution, this setting ensures that when the bottom of the protrusion fully contacts the top of the limiting post, the force-bearing surface of the entire pressure ring changes from the bottom of the pressure ring body and the top of the sensing diaphragm to the bottom of the protrusion and the top of the limiting post. This force-bearing surface transfer ensures that the sensing diaphragm will not be subjected to a value exceeding the rated pressure.
[0008] In a further embodiment, the top of the outer shell is completely open, the outer shell is a cylindrical structure, a sealing ring is fixedly installed on the top of the outer shell, a cylindrical protrusion is provided on the top of the pressure ring, the inner ring of the sealing ring and the diameter of the cylindrical protrusion are transition fit, the top of the cylindrical protrusion is higher than the top of the sealing ring, and a first sealing ring for sealing its contact surface with the inner wall of the sealing ring is sleeved on the cylindrical protrusion.
[0009] In a further embodiment, the bottom of the sealing ring is provided with an annular groove, and a second sealing ring is installed in the annular groove. The second sealing ring is used to seal the contact surface between the sealing ring and the top of the outer shell.
[0010] In a further embodiment, the bottom of the pressure ring is provided with a relief groove, which is used to avoid the deformation area of the sensing film.
[0011] In a further embodiment, all edges of the pressure ring are provided with a rounded acute-angle structure.
[0012] By adopting the above technical solution, the sharp edge is prevented from piercing the sensing film more sharply when deformed.
[0013] In summary, this utility model has the following beneficial effects: 1. When the bottom of the protrusion around the pressure ring contacts the top of the limiting post, the pressure ring cannot move further down. To ensure the flatness of the top of the limiting post and prevent the pressure ring from tilting, the best approach is to integrally mold the limiting post with the outer shell. The top of the supporting post is then quickly milled to a certain value using a milling cutter, and the end face of the supporting post is etched out using electrical discharge machining (EDM). Generally, EDM is used with copper electrodes. The flatness accuracy of the bottom of the copper electrode is the flatness accuracy of the top of the supporting post. Since the bottom of the copper electrode is open, it can be ground flat using a grinding machine. However, the top of the supporting post is recessed inside the outer shell, so this method is not suitable. Using copper electrode EDM can completely guarantee the top accuracy of multiple limiting posts. Attached Figure Description
[0014] Figure 1 This is a schematic diagram of the overall structure of this utility model; Figure 2 This is a schematic diagram illustrating the cooperative structure of the limiting module and the thin-film pressure sensor of this utility model.
[0015] In the figure, 1 is a thin-film pressure sensor; 11 is a housing; 12 is a sensing thin film; 13 is a pressure ring; 2 is a limiting module; 21 is a limiting post; 22 is a protrusion; 3 is a sealing ring; 4 is a first sealing ring; and 5 is a second sealing ring. Detailed Implementation
[0016] The present invention will be further described in detail below with reference to the accompanying drawings.
[0017] It should be noted that in the description of this utility model, any descriptions of orientation, such as up, down, front, back, left, right, etc., indicating orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed or operated in a specific orientation, and should not be construed as a limitation of this utility model.
[0018] Example 1: like Figure 1 - Figure 2As shown, a pressure sensor overload protection module includes a thin-film pressure sensor 1 and a limiting module 2 disposed inside the thin-film pressure sensor 1. The limiting module 2 is used to limit the maximum pressure that the thin film inside the thin-film pressure sensor 1 can withstand. The thin-film pressure sensor 1 includes a housing 11, a sensing thin film 12 installed inside the housing 11, and a pressure ring 13 slidably installed inside the housing 11. The pressure ring 13 is used to squeeze the periphery of the sensing thin film 12 to deform the sensing thin film 12. An annular protrusion is provided in the middle section of the inner side of the housing 11. The bottom of the sensing thin film 12 is attached to the top of the annular protrusion, and the bottom of the pressure ring 13 is attached to the top periphery of the sensing thin film 12. A plurality of protrusions 22 are axially and evenly arranged on the periphery of the pressure ring 13. The bottom end face of the protrusion 22 is not coplanar with the bottom end face of the pressure ring 13, and the top end face of the protrusion 22 is coplanar with the top end face of the pressure ring 13. The inner side of the housing 11 is provided with a ring that is aligned with the protrusions 22. A corresponding sliding groove is provided, with the length of the sliding groove running vertically. Each sliding groove has a limiting post 21 installed at its bottom. The top of the limiting post 21 is higher than the top of the annular protrusion. The top of the outer shell 11 is completely open. The outer shell 11 is cylindrical in shape. A sealing ring 3 is fixedly installed on the top of the outer shell 11. A cylindrical protrusion is provided on the top of the pressure ring 13. The inner ring of the sealing ring 3 and the diameter of the cylindrical protrusion are in transition fit. The top of the cylindrical protrusion is higher than the top of the sealing ring 3. A first sealing ring 4 is fitted on the cylindrical protrusion to close its contact surface with the inner wall of the sealing ring 3. A ring groove is provided at the bottom of the sealing ring 3. A second sealing ring 5 is installed in the ring groove. The second sealing ring 5 is used to close the contact surface between the sealing ring 3 and the top of the outer shell 11. A clearance groove is provided at the bottom of the pressure ring 13. The clearance groove is used to avoid the deformation area of the sensing film 12. All edges of the pressure ring 13 are provided with a rounded acute angle structure.
[0019] Specific implementation process: When the bottom of the protrusion 22 on the periphery of the pressure ring contacts the top of the limiting post, the pressure ring cannot move further down. In order to ensure the flatness of the top of the limiting post and avoid the pressure ring tilting, the best way is to integrally form the limiting post and the outer shell. The top of the support post is quickly milled to a certain value using a milling cutter. Then, the end face of the support post is etched out by electrical discharge etching. Generally, etching is done with copper electrodes. The flatness accuracy of the bottom of the copper electrode is the flatness accuracy of the top of the support post. Because the bottom of the copper electrode is open, it can be ground flat by a grinding machine. However, the top of the support post is recessed inside the outer shell, so this is not possible. The copper electrode discharge etching method can completely ensure the top accuracy of multiple limiting posts.
[0020] In the description of this utility model, unless otherwise explicitly defined, terms such as "setting," "installation," and "connection" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this utility model in conjunction with the specific content of the technical solution.
[0021] This specific embodiment is merely an explanation of the present utility model and is not intended to limit the present utility model. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but as long as they are within the scope of the claims of the present utility model, they are protected by patent law.
Claims
1. A pressure sensor overload protection module, characterized by: The device includes a thin-film pressure sensor (1) and a limiting module (2) disposed inside the thin-film pressure sensor (1). The limiting module (2) is used to limit the maximum pressure that the thin film inside the thin-film pressure sensor (1) can withstand. The thin-film pressure sensor (1) includes a housing (11), a sensing film (12) installed inside the housing (11), and a pressure ring (13) slidably installed inside the housing (11). The pressure ring (13) is used to squeeze the periphery of the sensing film (12) to cause the sensing film (12) to deform. An annular protrusion is provided in the middle section of the interior of the housing (11). The bottom of the sensing film (12) is attached to the top of the annular protrusion, and the bottom of the pressure ring (13) is attached to the top periphery of the sensing film (12). Multiple protrusions (22) are evenly arranged axially around the periphery of the pressure ring (13). The bottom end face of the protrusion (22) is not coplanar with the bottom end face of the pressure ring (13), and the top end face of the protrusion (22) is coplanar with the top end face of the pressure ring (13). The interior of the outer shell (11) is provided with a sliding groove corresponding to the protrusion (22). The length direction of the sliding groove is the vertical direction, and a limit post (21) is installed at the bottom of each sliding groove.
2. The pressure sensor overload protection module according to claim 1, characterized in that: The top of the limiting post (21) is higher than the top height of the annular protrusion.
3. The pressure sensor overload protection module according to claim 1, characterized in that: The top of the outer shell (11) is completely open. The outer shell (11) is a cylindrical structure. A sealing ring (3) is fixedly installed on the top of the outer shell (11). A cylindrical protrusion is provided on the top of the pressure ring (13). The inner ring of the sealing ring (3) and the diameter of the cylindrical protrusion are transitionally fitted. The top of the cylindrical protrusion is higher than the top of the sealing ring (3). A first sealing ring (4) is fitted on the cylindrical protrusion to close its contact surface with the inner wall of the sealing ring (3).
4. The pressure sensor overload protection module according to claim 3, characterized in that: The bottom of the sealing ring (3) is provided with an annular groove, and a second sealing ring (5) is installed in the annular groove. The second sealing ring (5) is used to seal the contact surface between the sealing ring (3) and the top of the outer shell (11).
5. The pressure sensor overload protection module according to claim 2, characterized in that: The bottom of the pressure ring (13) is provided with a relief groove, which is used to avoid the deformation area of the sensing film (12).
6. The pressure sensor overload protection module according to claim 2, characterized in that: All sides of the pressure ring (13) are provided with acute-angle rounded structures.