CN211291852U

CN211291852U - Pressure sensor

Info

Publication number: CN211291852U
Application number: CN202020262808.8U
Authority: CN
Inventors: 何杨
Original assignee: Jiangxi Xinli Sensing Technology Co ltd
Current assignee: Jiangxi Xinli Sensing Technology Co ltd
Priority date: 2020-03-05
Filing date: 2020-03-05
Publication date: 2020-08-18
Anticipated expiration: 2030-03-05

Abstract

The utility model relates to a pressure sensor, which comprises a sensor main body with a cavity, a signal output terminal led out from the cavity of the sensor main body, and a pressure sensing component arranged in the cavity of the sensor main body; the pressure sensor assembly comprises a bearing substrate, a pressure chip fixed on the bearing substrate and a PCBA circuit board electrically connected with the signal output terminal, wherein the PCBA circuit board is provided with a holding through hole, the pressure chip is arranged in the holding through hole and electrically connected with the PCBA circuit board, the bearing substrate is provided with a medium entering through hole and covered by the pressure chip, a medium entering channel is communicated with the medium entering through hole, the inside of the bearing substrate is sequentially filled with a pressure transfer liquid layer and a first gel layer, and the pressure transfer liquid layer is close to the bearing substrate. The utility model discloses a set up the holding through-hole on PCBA circuit board, arrange the pressure chip in the holding through-hole and integrated on the load-bearing substrate, and come transmission pressure through passing pressure liquid layer and first gel layer, reduce the volume.

Description

Pressure sensor

Technical Field

The utility model relates to a pressure measurement equipment field especially relates to a pressure sensor.

Background

The pressure sensor is a device or a device which can sense pressure signals and can convert the pressure signals into usable output electric signals according to a certain rule, is widely applied to various industrial automatic control environments, relates to various industries such as water conservancy and hydropower, railway traffic, intelligent buildings, aerospace and the like, and is mainly used for measuring the pressure of media (such as gas and liquid) and converting the pressure into the electric signals for output.

Most traditional pressure sensor are oil-filled sensor, adopt the structural style of oil-filled core promptly, the major structure adopts metal diaphragm and glass sintering base to encapsulate usually, the inside packaging has the pressure transmission oil of transmission pressure, pressure chip and kovar pin, metal diaphragm receives external pressure to take place to warp, and then transmits pressure signal for pressure chip through the pressure transmission oil, kovar pin draws forth from the major structure, pressure chip switches on and transmits pressure signal for the outer PCBA (printed Circuit Board Assembly) Circuit Board of major structure with kovar pin.

However, the above oil-filled sensor has drawbacks in that: the whole volume of the sensor is large, the sensor is not suitable for being embedded into a fine instrument or equipment, and the whole manufacturing process of the sensor needs various complex processes such as welding, glass sintering, vacuum oil filling and the like, so that the whole cost is high.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a pressure sensor to solve the bulky technical problem of pressure sensor among the prior art.

The utility model provides a pressure sensor, which comprises a sensor main body with a cavity, a signal output terminal led out from the cavity of the sensor main body and a pressure sensing assembly arranged in the cavity of the sensor main body;

the pressure sensor subassembly including the load-bearing substrate, fixed set up in pressure chip on the load-bearing substrate and with the PCBA circuit board that the signal output terminal electricity is connected, be equipped with the holding through-hole on the PCBA circuit board, pressure chip locates in the holding through-hole and with the PCBA circuit board electricity is connected, be equipped with the medium on the load-bearing substrate and get into the through-hole just the medium gets into the through-hole quilt the pressure chip covers, the medium gets into through-hole and a medium access passage intercommunication, it has biography pressure liquid layer and first gel layer to fill in proper order in the medium access passage, it is close to pass the pressure liquid layer the load-.

According to the utility model provides a pressure sensor has following beneficial effect: compare and need switch on pressure chip and the PCBA circuit board that is located the main structure outside through felling the pin, the utility model discloses with pressure chip and PCBA circuit board integration on load-bearing substrate, through set up the holding through-hole on the PCBA circuit board, arrange the pressure chip in the holding through-hole and through being connected with PCBA circuit board electricity, need not to set up the felling pin, and transmit pressure through the biography pressure liquid layer and the first gel layer in the medium access passage, need not to set up metal diaphragm and oil filler point, reduce pressure sensor's volume, simplify the preparation process, reduction in production cost.

In addition, according to the utility model provides a pressure sensor can also have following additional technical characterstic:

furthermore, a cover body is arranged on the surface, far away from the bearing substrate, of the PCBA, a gel inlet channel is arranged on the cover body in the axial direction, the gel inlet channel and the accommodating through hole are arranged correspondingly, and a second gel layer is filled in the gel inlet channel.

Furthermore, the center line of the gel inlet channel and the center line of the accommodating through hole are positioned on the same straight line, and the width of the gel inlet channel is larger than that of the accommodating through hole.

Furthermore, the surface of the PCBA circuit board, which is far away from the bearing substrate, is provided with an encapsulating adhesive layer, and the encapsulating adhesive layer is used for fixing the PCBA circuit package in the cavity of the sensor main body.

Further, the signal output terminal is electrically connected to an end of the PCBA circuit board.

Further, the outer surface of the medium inlet channel is provided with an annular sealing ring.

Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.

Drawings

The above and/or additional aspects and advantages of the present invention will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:

fig. 1 is a cross-sectional view of a pressure sensor in accordance with an embodiment of the present invention;

fig. 2 is a schematic structural diagram of a pressure sensing assembly and a signal output terminal of the pressure sensor according to the embodiment of the present invention;

fig. 3 is a schematic structural diagram of a pressure sensor according to an embodiment of the present invention;

fig. 4 is a flow chart of a method of making a pressure sensor according to another embodiment of the present invention;

10. a sensor body; 20. a signal output terminal; 30. a carrier substrate; 31. a medium enters the through hole; 40. a pressure chip; 50. a PCBA circuit board; 51. an accommodating through hole; 60. a media entry channel; 61. a pressure transmitting liquid layer; 62. a first gel layer; 70. a cover body; 71. a second gel layer; 80. pouring a sealing adhesive layer; 90. an annular seal ring.

Detailed Description

In order to make the objects, features and advantages of the present invention more comprehensible, embodiments of the present invention are described in detail below with reference to the accompanying drawings. Several embodiments of the invention are given in the accompanying drawings. The invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.

Referring to fig. 1 to 3, an embodiment of the present invention provides a pressure sensor, which includes a sensor main body 10 having a cavity, a signal output terminal 20 led out from the cavity of the sensor main body 10, and a pressure sensing assembly disposed in the cavity of the sensor main body 10.

The pressure sensor subassembly includes load-bearing substrate 30, fixed set up in pressure chip 40 on the load-bearing substrate 30 and with PCBA circuit board 50 that signal output terminal 20 electricity is connected, pressure chip 40 is the sensitive chip of MEMS pressure, be equipped with holding through-hole 51 on PCBA circuit board 50, pressure chip 40 locates in the holding through-hole 51 and with PCBA circuit board 50 electricity is connected, be equipped with medium entering through-hole 31 on the load-bearing substrate 30 just medium entering through-hole 31 quilt pressure chip 40 covers, medium entering through-hole 31 and a medium entering channel 60 intercommunication, it has pressure transmitting liquid layer 61 and first gel layer 62 to fill in proper order in the medium entering channel 60, and pressure transmitting liquid is silicon oil, pressure transmitting liquid layer 61 is close to load-bearing substrate 30.

The utility model discloses a theory of operation does: the measured medium firstly transmits the pressure to the first gel layer 62 positioned in the medium inlet channel 60, the first gel layer 62 transmits the pressure to the pressure transmitting liquid layer 61, then the pressure transmitting liquid layer 61 transmits the pressure to the pressure chip 40, the pressure chip 40 senses the pressure and transmits a pressure signal to the PCBA circuit board 50, the pressure signal is converted into a standard current and voltage signal through the PCBA circuit board 50, and then the standard current and voltage signal is output through the signal output terminal 20.

From the above description, the beneficial effects of the present invention are: compare and need switch on pressure chip 40 and the PCBA circuit board 50 that is located the main structure outside through kovar pin, the utility model discloses with pressure chip 40 and PCBA circuit board 50 integration on load-bearing substrate 30, through set up holding through-hole 51 on PCBA circuit board 50, arrange pressure chip 40 in holding through-hole 51 and be connected with PCBA circuit board 50 electricity, need not to set up kovar pin, and transmit pressure through pressure transfer liquid layer 61 and first gel layer 62 in medium access channel 60, need not to set up metal diaphragm and oil filler point, reduce pressure sensor's volume, simplify the preparation process, reduction in production cost.

In the embodiment of the present invention, the PCBA circuit board 50 is far away from the surface of the carrier substrate 30 is provided with a cover 70, the cover 70 is provided with a gel inlet channel along the axial direction, the gel inlet channel is correspondingly provided with the accommodating through hole 51, and the gel inlet channel is filled with the second gel layer 71.

The utility model discloses a bonding process is connected pressure chip 40 and PCBA circuit board 50, and the lead wire between pressure chip 40 and the PCBA circuit board 50 exposes in the outside air, for the protection lead wire, packs second gel layer 71 in the gel access way and covers the lead wire, and the material of second gel layer 71 is softer, can not press disconnected lead wire.

In the embodiment of the present invention, the center line of the gel inlet channel and the center line of the accommodating through hole 51 are located on the same straight line, and the width of the gel inlet channel is greater than the width of the accommodating through hole 51.

In order to protect and fix the pressure chip 40, the width of the gel inlet channel is greater than that of the accommodating through hole 51, so that the gel is filled into the accommodating through hole 51 along the gel inlet channel, the bottom and the periphery of the pressure chip 40 are protected by filling silicone oil and the gel, the contact with the gas and the liquid medium to be tested is avoided, and the service life of the pressure chip is prolonged.

In the embodiment of the present invention, the PCBA circuit board 50 is kept away from the surface of the carrier substrate 30 is provided with the potting adhesive layer 80, the potting adhesive layer 80 is used for fixing the PCBA circuit package in the cavity of the sensor main body 10.

In order to protect the PCBA circuit board 50, the outer surface of the PCBA circuit board 50 is filled with a potting adhesive layer 80, and the PCBA circuit board 50 is isolated from the outside by the potting adhesive layer 80.

In an embodiment of the present invention, the signal output terminal 20 is electrically connected to an end portion of the PCBA circuit board 50. The outer surface of the medium inlet channel 60 is provided with an annular sealing ring 90.

Referring to fig. 4, in another embodiment of the present invention, a method for manufacturing the pressure sensor further includes the following steps:

s10, the pressure chip 405 is mounted on the bearing substrate 30 through bonding glue and placed in an oven for high-temperature curing, the pressure chip 40 penetrates through the accommodating through hole 51 of the PCBA circuit board 50, the PCBA circuit board 50 is mounted on the bearing substrate 30 through 909 bonding glue in a bonding mode and placed in the oven for high-temperature curing, and the pressure chip 40 is electrically connected with the PCBA circuit board 50 through a bonding process to form the pressure sensing assembly.

And S20, mounting the pressure sensing assembly in the cavity of the sensor main body 10 by adhesive bonding, placing the sensor main body into an oven for high-temperature curing, and welding the signal output terminal 20 on the PCBA circuit board 50.

S30, injecting pressure-transmitting liquid and gel into the medium entering the channel 60 and curing, encapsulating the cavity of the sensor body 10.

The specific steps of packaging the cavity of the sensor body 10 in step S30 are as follows:

s31, the cover body 70 is connected to the PCBA 50 through adhesive glue, gel is filled into the gel inlet channel and solidified at high temperature, and then pouring sealant is injected into the surface of the PCBA 50 for packaging.

S40, finally, the annular sealing ring 90 is installed outside the medium inlet passage 60.

The utility model discloses a pressure sensor, medium entering channel 60 external diameter phi 7.5mm, sensor main part 10 length 24.6mm, wide 36mm, product total height 14.4mm, product total weight 10g, small, light in weight, simple to operate.

The utility model provides a pressure sensor preparation method realizes connecting and sealing through bonding and filling embedment glue and gel, need not multiple complicated processes such as welding, glass sintering, vacuum oil charge, simple process, low in production cost.

To sum up, the utility model provides a pressure sensor compares in prior art need switch on pressure chip 40 and the PCBA circuit board 50 that is located the major structure outside through felling the pin, the utility model discloses with pressure chip 40 and PCBA circuit board 50 integration on bearing substrate 30, through set up holding through-hole 51 on PCBA circuit board 50, arrange pressure chip 40 in holding through-hole 51 and through being connected with PCBA circuit board 50 electricity, need not to set up felling the pin, and pass through in the medium access passage 60 and press liquid layer 61 and first gel layer 62 and come transmission pressure, need not to set up metal diaphragm and oil filler point, reduce pressure sensor's volume, simplify the preparation process, reduction in production cost.

The above-mentioned embodiments only represent some embodiments of the present invention, and the description thereof is specific and detailed, but not to be construed as limiting the scope of the present invention. It should be noted that, for those skilled in the art, without departing from the spirit of the present invention, several variations and modifications can be made, which are within the scope of the present invention. Therefore, the protection scope of the present invention should be subject to the appended claims.

Claims

1. A pressure sensor is characterized by comprising a sensor main body with a cavity, a signal output terminal led out from the cavity of the sensor main body, and a pressure sensing assembly arranged in the cavity of the sensor main body;

the pressure sensor subassembly including the load-bearing substrate, fixed set up in pressure chip on the load-bearing substrate and with the PCBA circuit board that the signal output terminal electricity is connected, be equipped with the holding through-hole on the PCBA circuit board, pressure chip locates in the holding through-hole and with PCBA circuit board electricity is connected, be equipped with the medium on the load-bearing substrate and get into the through-hole just the medium gets into the through-hole quilt the pressure chip covers, the medium gets into through-hole and a medium access passage intercommunication, it has biography pressure liquid layer and first gel layer to fill in proper order in the medium access passage, it is close to pass the pressure liquid layer the load-bearing.

2. The pressure sensor according to claim 1, wherein a cover is disposed on a surface of the PCBA, the surface being away from the carrier substrate, the cover having a gel inlet channel axially disposed therein, the gel inlet channel corresponding to the receiving through hole, the gel inlet channel being filled with a second gel layer.

3. The pressure sensor of claim 2, wherein the centerline of the gel entry channel is collinear with the centerline of the receiving through-hole, and the gel entry channel has a width greater than the width of the receiving through-hole.

4. The pressure sensor of claim 1, wherein a surface of the PCBA circuit board remote from the carrier substrate is provided with a potting adhesive layer for securing the PCBA circuit package within the cavity of the sensor body.

5. The pressure sensor of claim 1, wherein the signal output terminal is electrically connected with an end of the PCBA circuit board.

6. A pressure sensor as claimed in claim 1, wherein the outer surface of the medium inlet passage is provided with an annular sealing ring.