阅读说明：本技术 一种压力传感器防水结构 (Pressure sensor waterproof construction ) 是由 许雄飞 罗志民 于 2021-07-30 设计创作，主要内容包括：本发明为一种压力传感器防水结构,属于压力传感器领域,针对现有压力传感器密封易失效导致电路板进水而影响传感器使用寿命的问题,采用技术方案如下：一种压力传感器防水结构,包括轴向限位、径向间隙配合的第一壳体和第二壳体,第一壳体设有第一腔体、第一凹腔和第一内壁；第二壳体内设有第二内壁、第二凹腔和第三腔体,第三腔体内有电路板；第二凹腔与第一凹腔合围并容纳感应芯片,第一密封圈位于感应芯片和第一内壁之间,在感应芯片与第一内壁之间形成密封,第二密封圈位于感应芯片和第二内壁之间,在感应芯片与第二内壁之间形成密封。本发明设置与大气相通的第二腔体,有效减少水汽累积,感应芯片两侧均形成密封,保证传感器的使用寿命。(The invention relates to a waterproof structure of a pressure sensor, belonging to the field of pressure sensors, aiming at the problem that the service life of the sensor is influenced by water inflow of a circuit board caused by the easy failure of the sealing of the existing pressure sensor, the technical scheme is as follows: a pressure sensor waterproof structure comprises a first shell and a second shell which are axially limited and radially clearance-matched, wherein the first shell is provided with a first cavity, a first concave cavity and a first inner wall; a second inner wall, a second concave cavity and a third cavity are arranged in the second shell, and a circuit board is arranged in the third cavity; the second cavity surrounds and holds the response chip with first cavity, and first sealing washer is located between response chip and the first inner wall, forms sealedly between response chip and first inner wall, and the second sealing washer is located between response chip and the second inner wall, forms sealedly between response chip and second inner wall. The second cavity communicated with the atmosphere is arranged, so that water vapor accumulation is effectively reduced, the two sides of the sensing chip are sealed, and the service life of the sensor is ensured.)

1. A waterproof structure for a pressure sensor, comprising:

a first shell (1), wherein a first cavity (11) and a first cavity (12) which are distinguished by a first inner wall (13) are arranged in the first shell (1), the first cavity (12) is positioned at a first end (A) of the first shell, the first cavity (11) is positioned at a second end (B) of the first shell, the first cavity (11) is communicated with the second end (B) of the first shell and the first cavity (12), and the second end (B) of the first shell is contacted with water so that the water flows into the first cavity (11);

the circuit board comprises a second shell (2), wherein a second cavity (21) and a third cavity (22) which are distinguished through a second inner wall (23) are arranged in the second shell (2), the second cavity (21) is located at the first end of the second shell (2), and a circuit board (6) is accommodated in the third cavity (22);

the first end of the second shell (2) is axially limited and radially clearance-matched with the first end (A) of the first shell, the second cavity (21) and the first cavity (12) are encircled to form a second cavity, the second cavity is internally provided with a sensing chip (5), one side of the sensing chip (5) is provided with a sensing cavity (52), the other side of the sensing chip is provided with a sensing resistor (51), the sensing cavity (52) is matched with the first cavity (11) in position so that water flowing into the first cavity (11) enters the sensing cavity (52), the circuit board (6) is connected with the sensing resistor (51), a first sealing ring (3) is abutted between the sensing chip (5) and the first inner wall (13), a seal is formed between the sensing chip (5) and the first inner wall (13), and a second sealing ring (4) is abutted between the sensing chip (5) and the second inner wall (23), a seal is formed between the sensing chip (5) and the second inner wall (23).

2. The waterproof structure of the pressure sensor according to claim 1, characterized in that the first end (A) of the first shell is provided with a blocking edge (14), the blocking edge (14) extends from the first end (A) of the first shell to enclose the first end of the second shell (2) therein, and has a radial clearance with the second shell (2), and the end of the blocking edge (14) abuts against the outside of the second shell (2), so that the first end (A) of the first shell and the first end of the second shell are axially limited and radially clearance-fitted.

3. The waterproof structure of the pressure sensor according to claim 2, characterized in that the second shell (2) has a curved surface (24), and the curved surface (24) abuts against the stop edge (14) to axially limit the first shell (1) and the second shell (2).

4. The pressure sensor waterproofing structure according to claim 3, wherein the curved surface (24) is a reduced diameter surface, and the curved surface (24) abuts against an inner side of the flange (14).

5. The waterproof structure of the pressure sensor according to claim 3, characterized in that an exhaust hole (241) is opened on the outer side wall of the curved surface (24), and the exhaust hole (241) is communicated with the radial clearance of the first shell (1) and the second shell (2).

6. The waterproof structure of a pressure sensor according to claim 2, characterized in that the first casing (1) has a protruding section (15) and a limiting section (16), the protruding section (15) being cylindrical, being located at the second end (B) of the first casing, for being inserted on the pump body of a water pump, the limiting section (16) being hexagonal-prism shaped, being located between the retaining edge (14) and the protruding section (15).

7. The waterproof structure of the pressure sensor according to claim 6, wherein the first shell (1) is provided with a limiting groove (17), and the limiting groove (17) is located at the joint of the protruding section (15) and the limiting section (16).

8. The waterproof structure of a pressure sensor according to claim 2, characterized in that the first housing (1) is a metal piece, and the flange (14) is formed by rolling.

9. The waterproof structure of a pressure sensor according to claim 1 or 8, characterized in that the second case (2) is a plastic member.

10. The waterproof structure of the pressure sensor according to claim 1, wherein a first groove (131) is formed in the first inner wall (13), the first groove (131) is communicated with the first cavity (12), the first sealing ring (3) is embedded in the first groove (131), and the sensing cavity (52) is enclosed by the first sealing ring (3).

Technical Field

The invention belongs to the field of pressure sensors, and particularly relates to a waterproof structure of a pressure sensor.

Background

Pressure sensors are widely used and include sensing components, processing circuitry and surrounding support material enclosed in a small sealed unit. The pressure sensors can be classified into diffused silicon type, ceramic resistance type and ceramic capacitance type pressure sensors according to the component classification of the sensing components.

Pressure sensors applied to water pumps are generally of the diffused silicon type and the ceramic resistance type. The existing diffused silicon pressure sensor adopts an oil seal technology, an oil-containing isolation layer is added between water and a measuring circuit to prevent water from permeating a processing circuit, but the existing diffused silicon pressure sensor has a complex production process and a large volume due to the existence of the oil-containing layer and is not a mainstream; the ceramic resistance sensor has the advantages of most wide application on the water pump, compact structure, sensitive induction, simple production process and low cost, and is an ideal pressure detection structure. The back printing of ceramic diaphragm has the thick film resistance in ceramic resistance sensor's structure, and the water that is detected directly acts on ceramic diaphragm, and when pressure exerted, ceramic diaphragm took place to deform, leads to diaphragm back resistance to change, and the sensor built-in circuit converts the resistance variation volume into the signal of telecommunication, realizes the pressure perception. The existing pressure sensor adopts a two-chamber structure, the pressure sensor comprises a high-pressure chamber in contact with water and an electric chamber for installing a circuit board, the high-pressure chamber and the electric chamber are only isolated through a sealing ring in a waterproof way, water finally penetrates through the sealing ring under the action of long-time high temperature and high pressure, and the short circuit at the position of the circuit board is reached to cause the failure of the sensor, so that the service life of the sensor is reduced, and the service life of the sensor cannot be effectively prolonged even if the circuit board is filled with glue.

Disclosure of Invention

Aiming at the problem that the service life of the sensor is affected by water inflow of a circuit board due to the fact that the existing pressure sensor is prone to failure in sealing, the invention provides the pressure sensor waterproof structure.

The technical scheme adopted by the invention is as follows: a pressure sensor waterproof structure comprising:

the water-saving water dispenser comprises a first shell, wherein a first cavity and a first cavity which are distinguished through a first inner wall are arranged in the first shell, the first cavity is positioned at the first end of the first shell, the first cavity is positioned at the second end of the first shell, the first cavity is communicated with the second end of the first shell and the first cavity, and the second end of the first shell is contacted with water so that the water can flow into the first cavity;

the second cavity is positioned at the first end of the second shell, and a circuit board is accommodated in the third cavity;

the first end of second casing with spacing, the radial clearance fit of first end axial of first casing, the second cavity surrounds with first cavity and forms a second cavity, be equipped with the response chip in the second cavity, one side of response chip is equipped with the response chamber, and the opposite side is equipped with sense resistor, the response chamber with first cavity position adaptation to the water that flows in first cavity gets into the response chamber, the circuit board with sense resistor links to each other, and a first sealing washer is contradicted between response chip and the first inner wall the response chip with form sealedly between the first inner wall, a second sealing washer contradict in between response chip and the second inner wall form sealedly between response chip and the second inner wall.

The first shell and the second shell are axially limited and have radial clearance, the matching part of the first cavity and the second cavity is not sealed, both sides of the induction chip are sealed, the induction chip is not sealed in the circumferential direction, so that the second cavity formed by encircling is communicated with the radial clearance and further communicated with the atmosphere, water vapor generated at the first cavity contacted with water can be discharged out of the second shell through the radial clearance, the induction chip respectively forms sealing at the first inner wall and the second inner wall, because the side contacted with the induction chip and the circuit board has no high-pressure and high-temperature influence, the service life of the second sealing ring is generally longer than that of the first sealing ring, therefore, even if the first sealing ring fails, the water vapor can be discharged through the clearance communicated with the second cavity and can not enter the third cavity, the drying in the third cavity is ensured, the possibility of water inlet of the circuit board is effectively reduced, and the sealing effect is better, effectively reduce the probability of circuit board short circuit, guarantee sensor's life.

Furthermore, a blocking edge is arranged at the first end of the first shell, extends from the first end of the first shell to enclose the first end of the second shell, and has a radial gap with the second shell, and the end of the blocking edge is abutted to the outer side of the second shell, so that the first end of the first shell and the first end of the second shell are axially limited and radially clearance-matched. The first shell and the second shell are limited through the extended blocking edge, so that an extra limiting part can be omitted, and the sensor is convenient to simplify the structure.

Furthermore, the second shell is provided with a curved surface, and the curved surface abuts against the blocking edge so as to realize axial limiting of the first shell and the second shell. For the plane, the curved surface is favorable for dispersing friction force, and the first shell and the second shell are effectively prevented from generating hard friction to wear and fall chips.

Further, the curved surface is a reducing surface, and the curved surface abuts against the inner side of the blocking edge. Set up the circuit board in the second casing, the circuit board is horizontal in the third cavity, and other parts settings that link to each other with the circuit board are in the second casing, and the area occupied by circuit board is the biggest usually, and other parts can set up the reducing surface and can save the materials according to space rational arrangement position, are favorable to reducing the shaping cost.

Furthermore, an exhaust hole is formed in the outer side wall of the curved surface, and the exhaust hole is communicated with the first shell and the second shell in a radial clearance mode. This arrangement facilitates the rapid evacuation of moisture that may accumulate in the gap between the two housings.

Furthermore, the first shell is provided with a protruding section and a limiting section, the protruding section is cylindrical and is located at the second end of the first shell and used for being inserted into a pump body of the water pump, and the limiting section is hexagonal and located between the blocking edge and the protruding section. Generally speaking, the connecting hole of seting up on the pump body of water pump is circular, and the setting of spacing section can ensure that sensor mounted position is appropriate, centre gripping atress when simultaneously can also easy to assemble.

Furthermore, a limiting groove is formed in the first shell and is located at the joint of the protruding section and the limiting section, so that the connecting piece or the sealing piece can be clamped, and the protruding section is prevented from falling off from the water pump.

Further, the first shell is a metal piece, and the blocking edge is formed in a rolling mode.

Furthermore, the second shell is a plastic part, so that the circuit board is insulated and is convenient to be injection molded.

Furthermore, a first groove is formed in the first inner wall and communicated with the first concave cavity, a first sealing ring is embedded in the first groove, and the sensing cavity is surrounded by the first sealing ring. The arrangement can ensure that most of water flowing in from the first cavity can be collected to the induction cavity, and the measurement accuracy is ensured. And a second groove communicated with the second concave cavity is formed in the second inner wall, and the second sealing ring is accommodated in the second groove.

The invention has the following beneficial effects: the axial is spacing, radial gapped between first casing and the second casing, and outside the steam that produces with the first cavity department of water contact can be discharged the second casing through radial gap, the response chip forms sealedly with first inner wall and second inner wall department respectively, guarantees the internal drying of third cavity simultaneously, effectively reduces the circuit board possibility of intaking, and sealed effect is better, effectively reduces the probability of circuit board short circuit, effectively improves and guarantees the life of sensor.

Drawings

FIG. 1 is a schematic view of the overall structure of a sensor;

FIG. 2 is a schematic view of a sensor mounting structure;

FIG. 3 is a schematic structural diagram of the second housing;

FIG. 4 is a schematic cross-sectional view of the sensor;

in the figure: 1-a first housing; 11-a first cavity; 12-a first cavity; 13-a first inner wall; 131-a first groove; 14-a flange; 15-a protruding section; 16-a limiting section; 17-a limiting groove; 2-a second housing; 21-a second cavity; 22-a third cavity; 23-a second inner wall; 231-a second groove; 24-curved surface; 241-exhaust holes; 3-a first sealing ring; 4-a second sealing ring; 5-induction chip; 51-a sense resistor; 52-a sensing chamber; 6-a circuit board; a-a first end of a first housing; b-a second end of the first housing; c-radial clearance.

Detailed Description

The technical solutions of the embodiments of the present invention are explained and explained below with reference to the drawings of the present invention, but the following embodiments are only preferred embodiments of the present invention, and not all embodiments. Based on the embodiments in the implementation, other embodiments obtained by those skilled in the art without any creative effort belong to the protection scope of the present invention.

The waterproof structure of the pressure sensor of the present embodiment, as shown in fig. 1 to 4, includes:

the water pump comprises a first shell 1, wherein a first end A of the first shell is provided with a first cavity 12, the first shell 1 is also provided with a first cavity 11, the first cavity 11 is communicated with a second end B of the first shell and the first cavity 12, the second end B of the first shell is inserted in a water pump and is contacted with water in the water pump, so that the water flows into the first cavity 11, a first inner wall 13 for distinguishing the first cavity 11 from the first cavity 12 is arranged in the first shell 1, a first groove 131 is formed in the first inner wall 13, the first groove 131 is communicated with the first cavity 12, and a first sealing ring 3 is embedded in the first groove 131;

a second inner wall 23, a second cavity 21 and a third cavity 22 which are communicated with each other are arranged in the second shell 2, the second inner wall 23 is used for distinguishing the second cavity 21 from the third cavity 22, the second cavity 21 is located at the first end of the second shell 2, a circuit board 6 is contained in the third cavity 22, the circuit board 6 can be fixed through glue filling, the sealing effect can be further enhanced after the glue is solidified, a second groove 231 communicated with the second cavity 21 is arranged on the second inner wall 23, and a second sealing ring 4 is contained in the second groove 231;

the first end of the first shell 1 is provided with a blocking edge 14, the blocking edge 14 extends outwards from the first end a of the first shell to enclose the first end of the second shell 2, a radial gap C is reserved between the blocking edge 14 and the second shell 2, the end of the blocking edge 14 is abutted against the outer side of the second shell 2, so that the first end of the first shell 1 and the first end of the second shell are axially limited and radially clearance-fitted, at the moment, the second cavity 21 and the first cavity 12 can enclose a second cavity communicated with the atmosphere, an induction chip 5 is arranged in the second cavity, one side of the induction chip 5 is provided with an induction cavity 52, the other side of the induction chip 5 is provided with an induction resistor 51, the induction cavity 52 is matched with the first cavity 11 in position, so that water flowing into the first cavity 11 enters the induction cavity 52, the first sealing ring 3 encloses the induction cavity 52, and most of water flowing from the first cavity can be collected to the induction cavity 52, guarantee measuring accuracy, circuit board 6 with sense resistor 51 links to each other, first sealing washer 3 is contradicted sense chip 5 with between the first inner wall 13 sense chip 5 with form sealedly between the first inner wall 13, second sealing washer 4 is contradicted sense chip 5 with between the second inner wall 23 it is sealed to form between sense chip 5 and the second inner wall 23.

The second cavity can be communicated with the atmosphere, water vapor generated at the position of the first cavity 11 contacted with water can be discharged to the outside of the second shell 2 through the radial gap C, the sensing chip 5 is respectively sealed with the first inner wall 13 and the second inner wall 23, because one side of the sensing chip 5 contacted with the circuit board 6 has no high-pressure high-temperature influence, the second sealing ring 4 is generally longer than the first sealing ring 3 in service life, therefore, even if the first sealing ring 3 fails, the water vapor can be discharged through the gap communicated with the second cavity, the water vapor and the water vapor cannot enter the third cavity 22, the dryness in the third cavity 22 is ensured, the possibility of water inflow of the circuit board 6 is effectively reduced, the sealing effect is better, the probability of short circuit of the circuit board 6 is effectively reduced, and the service life of the sensor is effectively improved and ensured.

The second shell 2 is provided with a curved surface 24, and the curved surface 24 is a reducing surface and is abutted against the inner side of the blocking edge 14, so that the axial limiting of the first shell 1 and the second shell 2 is realized. For the plane, curved surface 24 be provided with and do benefit to dispersion frictional force, effectively prevent to produce hard friction and wearing and tearing between first casing 1 and the second casing 2 and fall the bits, set up circuit board 6 in the second casing 2, circuit board 6 is horizontal in third cavity 22, other parts settings that link to each other with circuit board 6 are in second casing 2, generally speaking circuit board 6 area is the biggest, other parts can be according to the rational arrangement of space position, it can save materials to set up the reducing surface, be favorable to reducing the shaping cost.

An exhaust hole 241 is formed in the outer side wall of the curved surface 24, and the exhaust hole 241 is communicated with the radial clearance C of the first shell 1 and the second shell 2. This arrangement facilitates the rapid evacuation of moisture that may accumulate in the gap between the two housings.

The first shell 1 is provided with a protruding section 15 and a limiting section 16, the protruding section 15 is cylindrical and is located at the second end B of the first shell and used for being inserted into a pump body of a water pump, and the limiting section 16 is hexagonal and located between the blocking edge 14 and the protruding section 15. Generally speaking, the connecting hole that sets up on the pump body of water pump is circular, and the setting of spacing section 16 can ensure that sensor mounted position is suitable, and the centre gripping atress when still can the easy to assemble simultaneously.

The first shell 1 is provided with a limiting groove 17, and the limiting groove 17 is positioned at the joint of the protruding section 15 and the limiting section 16 so as to clamp a connecting piece or a sealing piece and prevent the protruding section 15 from falling off from the water pump.

First casing 1 is the metalwork, keep off the edge 14 and pass through the calendering mode shaping, and the accessible changes the shape of keeping off the edge 14 during dismantlement and makes first casing 1 and second casing 2 relieve spacing, and convenient dismantlement is convenient for circuit element and is retrieved and recycle and make things convenient for the sensor maintenance to change.

The second shell 2 is a plastic part, so that the circuit board 6 is insulated and convenient to be injection molded.

While the invention has been described with reference to specific embodiments, the scope of the invention is not limited thereto, and those skilled in the art will appreciate that the invention includes, but is not limited to, the accompanying drawings and the description of the embodiments above. Any modification which does not depart from the functional and structural principles of the present invention is intended to be included within the scope of the claims.