Pressure sensor packaging structure

Abstract

The utility model discloses a pressure sensor packaging structure, which relates to the technical field of pressure sensors, and comprises a substrate and a packaging shell, two sides of the top of the packaging shell are connected with a first labyrinth ring and a second labyrinth ring, an ash storage groove is arranged between the first labyrinth ring and the second labyrinth ring, the second labyrinth ring is sleeved with a labyrinth frame, and the labyrinth frame is sleeved with an ash storage groove. And a filter screen is connected into the labyrinth frame. Through the arrangement of the first labyrinth ring, the second labyrinth ring, the ash storage groove, the labyrinth frame and the filter screen, the first labyrinth ring, the second labyrinth ring and the labyrinth frame are matched to form a shorter labyrinth, so that part of impurities can be separated through centrifugal force when airflow passes through the labyrinth, and the filter screen can block large-particle impurities; the intercepted impurities can fall into the ash storage groove, more impurities can be contained in the ash storage groove, the phenomenon that airflow passing is affected by accumulated dust is reduced, and therefore the cleaning interval is prolonged; and most of large and medium particle impurities are effectively taken out, so that the blockage of the waterproof breathable film is slowed down.

Description

Technical Field

[0001] This utility model relates to the field of pressure sensor technology, specifically a pressure sensor packaging structure. Background Technology

[0002] Pressure sensor packaging is mainly divided into MEMS wafer-level packaging, metal welding packaging, injection molding and oil-filled isolation packaging. Among them, wafer-level packaging is an advanced packaging technology. Due to its advantages such as small size, excellent electrical performance, good heat dissipation and low cost, it has developed rapidly in recent years.

[0003] Existing MEMS wafer-level packaged pressure sensors have vents in their packaging shells to allow them to communicate with the outside atmosphere. To prevent water and dust from entering the packaging shell, a waterproof and breathable membrane is usually placed in front of the vents to provide waterproof and dustproof protection while allowing air to pass through. However, the pores of the waterproof and breathable membrane are small, and when it encounters larger dust particles, it is easy to become clogged. Over time, as the clogged area increases, it will affect the product's lifespan. Utility Model Content

[0004] Therefore, the purpose of this utility model is to provide a pressure sensor packaging structure to solve the technical problems mentioned in the background art.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a pressure sensor packaging structure, including a substrate and a packaging shell, wherein a first labyrinth ring and a second labyrinth ring are connected to the top two sides of the packaging shell, and a dust storage groove is provided between the first labyrinth ring and the second labyrinth ring, and a labyrinth frame is sleeved on the outside of the second labyrinth ring, and a filter screen is connected inside the labyrinth frame.

[0006] By adopting the above technical solution, during use, the first labyrinth ring, the second labyrinth ring, and the labyrinth frame work together to form a shorter labyrinth. This allows the airflow to pass through, and centrifugal force can separate some impurities. The filter screen will block large particles of impurities, and the trapped impurities will fall into the ash storage tank. The existence of the ash storage tank can hold more impurities, reducing the phenomenon of dust accumulation affecting airflow and thus extending the cleaning interval. Moreover, the cleaning operation is also relatively simple. Just rotate the labyrinth frame to disassemble it and expose the ash storage tank, at which point the impurities in the ash storage tank can be processed. Furthermore, due to the short labyrinth path, the large circular flow area, the rounded corners to reduce resistance, and the large pore size of the filter screen, the airflow is not blocked by the labyrinth and the filter screen, which would lead to a significant increase in static pressure response time and reduces flow resistance.

[0007] Furthermore, the middle of one side of both the first and second maze rings is arc-shaped, and the bottom of the maze frame is semi-circular.

[0008] By adopting the above technical solutions, the maze path is short, the circular flow area is large, and the rounded corners are set to reduce resistance, thereby avoiding the airflow being blocked by the maze and the filter, which would lead to a significant increase in static pressure response time and reduce flow resistance.

[0009] Furthermore, the maze frame is threadedly connected to the second maze ring.

[0010] By adopting the above technical solution, during cleaning, the ash storage tank can be exposed by simply rotating and disassembling the maze frame, at which point the impurities in the ash storage tank can be treated.

[0011] Furthermore, the pore size of the filter screen is greater than or equal to 100 μm.

[0012] By adopting the above technical solution, the filter screen has a larger pore size, which avoids causing greater resistance to airflow and thus reduces the impact on the accuracy of pressure detection.

[0013] Furthermore, contacts are provided on both sides of the bottom of the substrate, a MEMS chip is mounted on the top of the substrate, and gel is provided on both sides of the top of the substrate.

[0014] By adopting the above technical solution, the contacts facilitate current conduction, and the MEMS chip, together with the ASIC chip mounted on the substrate behind it, can detect pressure. The presence of gel helps protect the two chips and can transmit pressure to the MEMS chip.

[0015] Furthermore, the encapsulation shell is made of stainless steel and is fixed to the periphery of the substrate by epoxy resin adhesive.

[0016] By adopting the above technical solution, the encapsulation shell is made of stainless steel, which has the advantages of high strength and corrosion resistance, and can also play an electromagnetic shielding role to reduce electromagnetic interference to the sensor.

[0017] Furthermore, the top of the encapsulation shell is provided with air holes, and a waterproof and breathable membrane is fixed to the top of the air holes with an organic silicone adhesive.

[0018] By adopting the above technical solution, the vent design facilitates communication between the inside of the encapsulated shell and the atmosphere, thereby facilitating pressure testing, while the waterproof and breathable membrane prevents water and dust from entering.

[0019] Furthermore, the first maze ring, the second maze ring, and the maze frame are all made of stainless steel, and the first and second maze rings are fixedly connected to the encapsulation shell by welding.

[0020] By adopting the above technical solution, when preparing the outer shell, the first labyrinth ring and the labyrinth switch can be fixed to the top of the encapsulation shell by low-temperature welding. Then, the waterproof and breathable membrane and other structures can be fixed to the encapsulation shell, thus avoiding the welding temperature from burning the waterproof and breathable membrane and the silicone adhesive.

[0021] In summary, the present invention has the following main advantages:

[0022] This invention utilizes a combination of a first labyrinth ring, a second labyrinth ring, a dust collection trough, a labyrinth frame, and a filter screen. The cooperation of these components forms a relatively short labyrinth, allowing centrifugal force to separate some impurities as airflow passes through. The filter screen blocks large particles, and the trapped impurities fall into the dust collection trough. This trough can hold more impurities, reducing dust accumulation and thus extending the cleaning interval. Cleaning is simple; the labyrinth frame can be rotated to remove it and expose the dust collection trough, allowing for the removal of impurities. The short labyrinth path, large circular flow area, rounded corners to reduce resistance, and large filter screen pore size prevent airflow from being blocked by the labyrinth and filter screen, thus avoiding prolonged static pressure response time and reducing flow resistance. This effectively removes most medium to large particles, reducing clogging of the waterproof and breathable membrane. Attached Figure Description

[0023] Figure 1 This is a cross-sectional structural diagram of the present invention;

[0024] Figure 2 This is a schematic diagram of the maze frame structure of this utility model;

[0025] Figure 3 This is a schematic diagram of the cross-sectional structure of the maze frame of this utility model;

[0026] Figure 4 This is a schematic diagram of the explosion structure of the labyrinth frame of this utility model.

[0027] In the diagram: 1. Substrate; 2. Contact; 3. MEMS chip; 4. Encapsulation shell; 5. Gel; 6. First labyrinth ring; 7. Second labyrinth ring; 8. Ash storage tank; 9. Labyrinth frame; 10. Filter screen; 11. Vent; 12. Waterproof and breathable membrane. Detailed Implementation

[0028] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0029] The embodiments of this utility model will be described below based on its overall structure.

[0030] Example 1:

[0031] A pressure sensor packaging structure, such as Figures 1-4 As shown, the device includes a substrate 1 and a packaging shell 4. A first labyrinth ring 6 and a second labyrinth ring 7 are connected to the top two sides of the packaging shell 4. One side of both the first labyrinth ring 6 and the second labyrinth ring 7 is arc-shaped. A dust collection groove 8 is provided between the first labyrinth ring 6 and the second labyrinth ring 7. A labyrinth frame 9 is sleeved on the outside of the second labyrinth ring 7. The bottom of the labyrinth frame 9 is semi-circular. The labyrinth frame 9 is threadedly connected to the second labyrinth ring 7. A filter screen 10 is connected inside the labyrinth frame 9. The pore size of the filter screen 10 is greater than or equal to 100μm. In use, the cooperation of the first labyrinth ring 6, the second labyrinth ring 7, and the labyrinth frame 9 forms a relatively short labyrinth, allowing airflow to pass through and be centrifuged. The filter 10 separates some impurities and blocks large particles. The trapped impurities fall into the ash storage tank 8. The ash storage tank 8 can hold more impurities, reducing the phenomenon of dust accumulation affecting airflow and thus extending the cleaning interval. The cleaning operation is also relatively simple. Just rotate the labyrinth frame 9 to disassemble it and expose the ash storage tank 8. At this time, the impurities in the ash storage tank 8 can be processed. Furthermore, due to the short labyrinth path, the large circular flow area, the rounded corners to reduce resistance, and the large pore size of the filter 10, the airflow is not blocked by the labyrinth and the filter 10, which would lead to a significant increase in static pressure response time and reduce flow resistance.

[0032] See Figure 1 In the above embodiment, contacts 2 are provided on both sides of the bottom of the substrate 1 to facilitate the conduction of electrical signals and current; a MEMS chip 3 is installed on the top of the substrate 1, and an ASIC chip installed on the top of the substrate 1 is also provided behind the MEMS chip 3. The structure is blocked by the MEMS chip 3 and is not shown in the figure, which facilitates pressure detection; gel 5 is provided on both sides of the top of the substrate 1 to protect the MEMS chip 3 and the ASIC chip, and to transmit pressure to the MEMS chip 3; the encapsulation shell 4 is made of stainless steel and is fixed to the periphery of the substrate 1 with epoxy resin adhesive, which is high in strength and corrosion resistant; the top of the encapsulation shell 4 has an air hole 11, and a waterproof and breathable membrane 12 is fixed to the top of the air hole 11 with silicone adhesive, which allows airflow to pass through normally to detect pressure and prevents water and dust from entering.

[0033] Example 2:

[0034] Based on the above embodiment one, the following settings are now adopted for ease of processing.

[0035] See Figure 1In the above embodiments, the first maze ring 6, the second maze ring 7, and the maze frame 9 are all made of stainless steel. The first maze ring 6 and the second maze ring 7 are fixedly connected to the encapsulation shell 4 by welding. When preparing the shell, the first maze ring 6 and the maze ring 7 are fixed to the top of the encapsulation shell 4 by low-temperature welding. Then, the waterproof and breathable membrane 12 and other structures are fixed to the encapsulation shell 4 to avoid the welding temperature burning the waterproof and breathable membrane 12 and the silicone adhesive.

[0036] The implementation principle of this utility model is as follows: First, the specific tooling process is the prior art. The content of this technical solution is the same as the existing disclosed technology. The difference is that the air hole 11 and the waterproof and breathable membrane 12 are pre-installed with a maze plus filter 10 dustproof structure, which has no impact on the packaging process. Therefore, the traditional MEMS wafer-level packaging process can be used.

[0037] When preparing the outer shell, the first labyrinth ring 6 and the labyrinth ring are fixed to the top of the encapsulation shell 4 by low-temperature welding. Then, the waterproof and breathable membrane 12 and other structures are fixed to the encapsulation shell 4 to avoid the welding temperature burning the waterproof and breathable membrane 12 and the silicone adhesive. Then, the filter screen 10 is placed on the top of the first labyrinth ring 6, and the labyrinth frame 9 is fitted onto the outside of the second labyrinth ring 7 by threaded connection to complete the production and assembly of the improved point of this technical solution.

[0038] In use, the first labyrinth ring 6, the second labyrinth ring 7, and the labyrinth frame 9 work together to form a relatively short labyrinth. This allows the airflow to pass through and separate some impurities through centrifugal force. The filter screen 10 blocks large particles of impurities, and the trapped impurities fall into the ash storage tank 8. The ash storage tank 8 can hold more impurities, reducing the phenomenon of dust accumulation affecting airflow and thus extending the cleaning interval. Cleaning is also relatively simple; the labyrinth frame 9 can be rotated to disassemble it and expose the ash storage tank 8, at which point the impurities in the ash storage tank 8 can be processed. Furthermore, due to the short labyrinth path, the large circular flow area, the rounded corners to reduce resistance, and the large pore size of the filter screen 10, the airflow is not blocked by the labyrinth and the filter screen 10, which would lead to a significant increase in static pressure response time and reduce flow resistance.

[0039] Although embodiments of the present invention have been shown and described, these specific embodiments are merely explanations of the present invention and are not intended to limit the invention. The specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. After reading this specification, those skilled in the art may make modifications, substitutions, and variations to the embodiments as needed without departing from the principles and spirit of the present invention, provided that such modifications, substitutions, and variations are within the scope of the claims of the present invention and are protected by patent law.

Claims

1. A pressure sensor package structure comprising a substrate (1) and a package housing (4), characterized in that: The first labyrinth ring (6) and the second labyrinth ring (7) are connected to the two sides of the top of the packaging shell (4), and the ash storage groove (8) is arranged between the first labyrinth ring (6) and the second labyrinth ring (7), the second labyrinth ring (7) is sleeved with the labyrinth frame (9) outside, and the labyrinth frame (9) is connected with the filter screen (10) inside.

2. The pressure sensor package structure of claim 1, wherein: The first labyrinth ring (6) and the second labyrinth ring (7) are connected to the two sides of the top of the packaging shell (4), and the ash storage groove (8) is arranged between the first labyrinth ring (6) and the second labyrinth ring (7), the second labyrinth ring (7) is sleeved with the labyrinth frame (9) outside, and the labyrinth frame (9) is connected with the filter screen (10) inside.

3. The pressure sensor package structure of claim 2, wherein: The labyrinth frame (9) and the second labyrinth ring (7) are screw-connected.

4. The pressure sensor package structure of claim 1, wherein: The pore size of the filter screen (10) is greater than or equal to 100 microns.

5. The pressure sensor package structure of claim 1, wherein: The bottom of the substrate (1) is provided with the contact (2) on both sides, the top of the substrate (1) is provided with the mems chip (3), and the top of the substrate (1) is provided with the gel (5).

6. The pressure sensor package structure of claim 5, wherein: The packaging shell (4) is made of stainless steel material, and the packaging shell (4) is fixed around the substrate (1) by an epoxy resin adhesive.

7. The pressure sensor package structure of claim 6, wherein: The packaging shell (4) is made of stainless steel material, and the packaging shell (4) is fixed around the substrate (1) by an epoxy resin adhesive.

8. The pressure sensor package structure of claim 3, wherein: The first labyrinth ring (6), the second labyrinth ring (7) and the labyrinth frame (9) are made of stainless steel material, and the first labyrinth ring (6) and the second labyrinth ring (7) are fixedly connected with the packaging shell (4) by welding.

Images