A preformed frame packaged door pressure sensor

Abstract

The utility model discloses a door pressure sensor of preforming frame package relates to pressure sensor technical field. Including: base, the inside hollow of base is provided with upper cover at the top, is provided with lower cover at the bottom, install ring, install ring setting in the middle part of base, the top of install ring is install cavity, and the bottom of install ring is provided with through -hole, chip, chip sets up on install ring, and the pressure sensing diaphragm of chip corresponds with through -hole, be provided with guide hole on lower cover, and the pressure sensing diaphragm of guide hole is opposite chip, and the size of guide hole is adapted to through -hole. The utility model discloses through preforming frame fixed chip and each component, avoid structural displacement, install ring fixed chip can reduce the impact that chip received simultaneously, and buffer cavity, buffer solution and isolation diaphragm cooperation, ensure pressure transmission steady, improve detection accuracy, and through arc baffle blocks big block impurity, and water -repellent oil -repellent coating reduces adhesion, and realizes active cleaning through cleaning hole, effectively solves the problem of impurity block.

Description

Technical Field

[0001] This utility model relates to the field of pressure sensor technology, and in particular to a door pressure sensor with a pre-formed frame package. Background Technology

[0002] In automotive automatic door control systems, door pressure sensors are core components that ensure safe operation. Their main function is to detect the pressure value during the closing process of the car door in real time. When the pressure exceeds a preset threshold, it triggers the door to open in reverse or stop, preventing injury to people or damage to items.

[0003] Existing door pressure sensors mostly use traditional packaging structures, which have the following shortcomings: First, the internal buffer structure of the sensor is poorly designed, and the pressure transmission path is easily blocked by impurities, resulting in a decrease in detection accuracy; second, there is a lack of effective cleaning and protection mechanisms, and dust, oil, and moisture in the door's operating environment can easily enter the sensor, affecting the sensitivity of the chip's pressure-sensing diaphragm; third, the sensor's performance stability is poor in low-temperature and humid environments. For example, at low temperatures, component stiffness leads to pressure response delay, further reducing detection accuracy. Utility Model Content

[0004] The main objective of this invention is to provide a door pressure sensor with a pre-formed frame package to solve the above-mentioned problems.

[0005] To achieve the above objectives, this utility model provides a door pressure sensor encapsulated in a pre-formed frame, comprising: A base, the base being hollow inside, with an upper cover at the top and a lower cover at the bottom; The mounting ring is located in the middle of the base, with a mounting cavity above it and a through hole at the bottom. A chip, wherein the chip is disposed on the mounting ring, and the pressure-sensitive diaphragm of the chip corresponds to the through hole; The lower cover is provided with a guide hole, which is directly opposite the pressure-sensitive diaphragm of the chip, and the size of the guide hole is adapted to the through hole.

[0006] Furthermore, a buffer cavity is provided below the mounting ring. The buffer cavity is cylindrical and coaxial with the through hole. The guide hole communicates with the buffer cavity.

[0007] Furthermore, the bottom of the buffer cavity is inclined toward the guide hole.

[0008] Furthermore, the lower cover is also provided with a plurality of first cleaning holes, which are evenly distributed around the guide hole. The side wall of the buffer cavity is evenly distributed with a plurality of second cleaning holes corresponding to the first cleaning holes. The first cleaning holes are connected to the corresponding second cleaning hole pipes. The second cleaning holes are inclined toward the bottom of the buffer cavity. The first cleaning holes are provided with electromagnetic valves or connected to air sources.

[0009] Furthermore, an arched baffle is provided at the entrance end of the guide hole, and an opening is provided on one side of the arched baffle, through which the guide hole communicates with the outside.

[0010] Furthermore, the guide hole and the inner wall of the buffer cavity are provided with a hydrophobic and oleophobic coating.

[0011] Furthermore, an isolation diaphragm is provided at the outlet end of the guide hole, and a buffer solution is provided inside the buffer cavity.

[0012] Furthermore, a miniature vibration motor is provided on the side wall of the base.

[0013] Furthermore, a miniature heating resistor is provided on the side wall of the base.

[0014] Furthermore, an arched baffle is provided at the entrance end of the guide hole, and an opening is provided on one side of the arched baffle, through which the guide hole communicates with the outside.

[0015] This utility model has the following beneficial effects: This invention uses a pre-formed frame (base, mounting ring) to fix the chip and other components, reducing impact and preventing structural displacement; the coaxial design of the buffer chamber and guide hole, and the cooperation of the buffer solution and the isolation diaphragm, ensure stable pressure transmission and improve detection accuracy; and the arched baffle blocks large impurities, the hydrophobic and oleophobic coating reduces adhesion, and the cleaning hole enables active cleaning, effectively solving the problem of impurity blockage. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of an embodiment of a preformed frame-encapsulated door pressure sensor according to the present invention; Figure 2 This is a schematic diagram of the first cleaning hole of a door pressure sensor encapsulated in a preformed frame according to the present invention. Figure 3 This is a schematic diagram of another embodiment of the door pressure sensor with a pre-formed frame package according to the present invention.

[0017] In the diagram: 1-Base; 2-Upper cover; 3-Lower cover; 4-Mounting ring; 5-Guide hole; 6-Mounting cavity; 7-Buffer cavity; 8-First cleaning hole; 9-Second cleaning hole; 10-Isolation membrane; 11-Buffer solution; 12-Arch-shaped baffle. Detailed Implementation

[0018] To achieve the above objectives and effects, the technical means and structure adopted by this utility model are described in detail with reference to the accompanying drawings, focusing on the features and functions of the preferred embodiments of this utility model.

[0019] As attached Figures 1-3 As shown, this utility model provides a door pressure sensor with a pre-formed frame package, comprising: The base 1 is a hollow cylindrical or square structure with a detachable top cover 2 and a sealed bottom cover 3, forming a closed pre-formed encapsulation frame that effectively isolates external impurities and moisture. Mounting ring 4 is fixedly installed on the inner wall of the middle part of the base 1. Mounting ring 4 divides the internal space of the base 1 into upper and lower spaces. The upper part of mounting ring 4 is the mounting cavity, which is used to place the chip. Mounting ring 4 is provided with through holes for airflow. The chip uses a MEMS piezoresistive pressure sensing chip, which is fixedly mounted on the upper surface of the mounting ring 4. The pressure sensing diaphragm of the chip is set downwards and directly opposite the through hole. The lower cover 3 is provided with a guide hole 5. The upper end of the guide hole 5 is adapted to the through hole on the mounting ring 4, and the lower end is connected to the outside. External pressure can be accurately transmitted to the pressure-sensing diaphragm through the guide hole 5 to cause it to deform and convert the pressure into an electrical signal.

[0020] Specifically, the guide hole 5 abuts against the mounting ring 4, and there is a certain gap between the mounting ring 4 and the lower cover 3, so as to reduce the impact of external stress on the chip.

[0021] Preferably, an elastic gasket is provided between the mounting ring 4 and the lower cover 3.

[0022] In this embodiment, a buffer cavity 7 is provided below the mounting ring 4. The buffer cavity 7 is coaxially arranged with the through hole, and the lower end of the guide hole 5 is connected to the buffer cavity 7.

[0023] When the airflow enters the buffer cavity 7 through the guide hole 5, it rapidly diffuses and decelerates, generating eddies and turbulence. This actively dissipates the impact kinetic energy and forms a uniformly distributed static pressure field within the cavity. This static pressure field acts on the entire effective area of ​​the pressure-sensitive diaphragm of the MEMS sensing chip, causing it to deform and thus converting pressure into an electrical signal. This effectively avoids the directional impact and localized stress concentration on the pressure-sensitive diaphragm caused by external pressure media, especially the high-speed airflow generated during a car door collision, greatly improving the reliability and long-term stability of the sensor under high-pressure impact environments.

[0024] Specifically, the bottom of the buffer chamber 7 is inclined toward the guide hole 5, and the inclination angle is preferably 3°-5°. This inclined structure allows impurities such as dust and liquid entering the buffer chamber 7 to gather toward the guide hole 5 under the action of gravity and leave from the guide hole 5. At the same time, it optimizes the pressure transmission path and reduces pressure loss.

[0025] Specifically, the number of chips can be set to multiple, with a certain gap between the multiple chips. The multiple chips are bonded together by gold wires, and the chips and bonding wires are bonded and protected using jelly glue.

[0026] In this embodiment, the lower cover 3 is also provided with a plurality of first cleaning holes 8, which are evenly distributed around the guide hole 5, preferably four, with an adjacent hole spacing of 90°; the side wall of the buffer cavity 7 is provided with a plurality of second cleaning holes 9 corresponding one-to-one with the first cleaning holes 8, and each first cleaning hole 8 and the corresponding second cleaning hole 9 are connected through a pipeline preset inside the base 1; the second cleaning holes 9 are inclined toward the bottom of the buffer cavity 7, and the inclination direction is consistent with the inclination direction of the bottom of the buffer cavity 7, so as to ensure that the cleaning medium, such as compressed air or cleaning liquid, can cover the inner wall of the buffer cavity 7; a solenoid valve can be selectively installed on the first cleaning hole 8, or an external air source, such as a compressed air pump, can be connected to clean the guide hole 5 and the buffer cavity 7 regularly to prevent impurities from clogging.

[0027] Specifically, when the solenoid valve is opened, the airflow generated when the car door is opened and closed can enter through the first cleaning hole 8 and exit through the second cleaning hole 8 to clean the guide hole 5 and the buffer chamber 7.

[0028] In this embodiment, an arched baffle 12 is provided at the entrance end of the guide hole 5. The arched baffle 12 has an arc-shaped structure with an opening reserved on one side. The guide hole 5 communicates with the outside through this opening. The arched baffle 12 can block large impurities such as paper scraps and small stones from directly entering the guide hole 5, while preventing rainwater and oil stains from directly washing the entrance of the guide hole 5, thus playing a preliminary protective role.

[0029] In this embodiment, the inner walls of the guide hole 5 and the buffer cavity 7 are coated with a hydrophobic and oleophobic coating such as a polytetrafluoroethylene coating with a thickness of 5-10 μm. This coating can reduce the adhesion of water vapor and oil stains on the wall surface, reduce the probability of impurities clogging, and at the same time improve the corrosion resistance of the inner wall.

[0030] In another embodiment, an isolation diaphragm 10 is provided at the outlet end of the guide hole 5. The isolation diaphragm 10 can be made of polyimide material with a thickness of 0.05-0.1mm, which has good elasticity and corrosion resistance, and can prevent external impurities from entering the buffer chamber 7. The buffer chamber 7 is filled with a buffer solution 11, such as methyl silicone oil. When external pressure is generated, the isolation diaphragm will deform and squeeze the buffer solution 11. The buffer solution 11 can convert the instantaneous impact force of the external force into a stable pressure and transmit it to the pressure-sensitive diaphragm, avoiding damage to the diaphragm due to impact, and improving the stability of pressure detection.

[0031] During implementation, a micro vibration motor can be embedded in the side wall of the base 1. Specifically, a piezoelectric ceramic sheet can be selected. The micro vibration motor is electrically connected to the external control circuit. When the sensor performs cleaning operation, the micro vibration motor can be activated to generate high-frequency micro vibration, which helps the impurities in the buffer chamber 7 and the inner wall of the guide hole 5 to separate, thereby improving the cleaning effect. At the same time, in a low-temperature environment, slight vibration can prevent the buffer solution 11 from coagulating locally.

[0032] Furthermore, a miniature heating resistor is embedded in the side wall of the base 1. The miniature heating resistor works in conjunction with the temperature sensor. When the ambient temperature is below 0°C or moisture enters, the temperature sensor sends a signal to the control circuit to activate the heating resistor. The heating resistor generates local heat to evaporate the intruded moisture and prevent freezing and blockage. At the same time, it can maintain the internal temperature of the base 1 at 5°C-10°C, avoiding pressure response delay caused by the solidification of the buffer solution 11 and stiffness of the components, and ensuring that the sensor works normally in low-temperature environments.

[0033] The above description is only a preferred embodiment of the present utility model and not all embodiments. Anyone should know that structural changes made under the guidance of the present utility model are protected by the present utility model. All technical solutions that are the same as or similar to the present utility model are protected by the present utility model.

Claims

1. A door pressure sensor encapsulated in a pre-formed frame, characterized in that, include: The base (1) is hollow inside, with an upper cover (2) on the top and a lower cover (3) on the bottom. Mounting ring (4), the mounting ring (4) is located in the middle of the base (1), the upper part of the mounting ring (4) is the mounting cavity (6), and the bottom of the mounting ring (4) is provided with a through hole; The chip is disposed on the mounting ring (4), and the pressure-sensitive diaphragm of the chip corresponds to the through hole; The lower cover (3) is provided with a guide hole (5), which is directly opposite the pressure-sensitive diaphragm of the chip, and the size of the guide hole (5) is adapted to the through hole.

2. The door pressure sensor with a pre-formed frame as described in claim 1, characterized in that, A buffer cavity (7) is provided below the mounting ring (4). The buffer cavity (7) is cylindrical and coaxial with the through hole. The guide hole (5) is connected to the buffer cavity.

3. The door pressure sensor with a pre-formed frame as described in claim 2, characterized in that, The bottom of the buffer cavity (7) is inclined toward the guide hole (5).

4. The door pressure sensor with a pre-formed frame as described in claim 3, characterized in that, The lower cover (3) is also provided with a plurality of first cleaning holes (8), which are evenly distributed around the guide hole (5). The side wall of the buffer cavity (7) is evenly distributed with a plurality of second cleaning holes (9) corresponding to the first cleaning holes (8). The first cleaning holes (8) are connected to the corresponding second cleaning holes (9) by pipeline. The second cleaning holes (9) are inclined toward the bottom of the buffer cavity (7). The first cleaning holes (8) are provided with electromagnetic valves or connected to air sources.

5. A door pressure sensor with a pre-formed frame as described in claim 2, characterized in that, The inner walls of the guide hole (5) and the buffer cavity (7) are provided with a hydrophobic and oleophobic coating.

6. A door pressure sensor with a pre-formed frame package as described in claim 2, characterized in that, An isolation diaphragm (10) is provided at the outlet end of the guide hole (5), and a buffer solution (11) is provided in the buffer cavity (7).

7. A door pressure sensor with a pre-formed frame enclosure as described in any one of claims 1-6, characterized in that, A miniature vibration motor is provided on the side wall of the base (1).

8. The door pressure sensor with a pre-formed frame package as described in claim 7, characterized in that, The base (1) has a miniature heating resistor on its side wall.

9. A door pressure sensor with a pre-formed frame package as described in claim 7, characterized in that, An arched baffle (12) is provided at the entrance end of the guide hole (5), and an opening is provided on one side of the arched baffle (12), through which the guide hole (5) communicates with the outside.

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