CN215178321U

CN215178321U - Differential pressure sensor

Info

Publication number: CN215178321U
Application number: CN202120255287.8U
Authority: CN
Inventors: 聂泳忠; 吴晓东; 唐长明; 林李亮
Original assignee: Fatri United Testing and Control Quanzhou Technologies Co Ltd
Current assignee: Fatri United Testing and Control Quanzhou Technologies Co Ltd
Priority date: 2021-01-29
Filing date: 2021-01-29
Publication date: 2021-12-14
Anticipated expiration: 2031-01-29

Abstract

The utility model discloses a differential pressure sensor, differential pressure sensor includes: the shell is provided with a cavity, and a first vent hole and a second vent hole are formed in the shell; the conditioning circuit board is arranged in the cavity and divides the cavity into a first cavity and a second cavity, the first air vent is communicated with the first cavity, the second air vent is communicated with the second cavity, and a through hole communicated with the first cavity and the second cavity is formed in the conditioning circuit board; the pressure chip is arranged in the first cavity, is fixed on the conditioning circuit board and is arranged corresponding to the through hole, so that the pressure of the second cavity can be transmitted to the pressure chip through the through hole, and the pressure chip is electrically connected with the conditioning circuit board. The utility model discloses differential pressure sensor's encapsulation size can be reduced, differential pressure sensor's miniaturization is realized.

Description

Differential pressure sensor

Technical Field

The utility model relates to a sensor technical field, concretely relates to differential pressure sensor.

Background

A differential pressure sensor is a sensor used to measure the difference between two pressures. With the development of Micro-Electro-Mechanical systems (MEMS) technology, differential pressure sensors are further developed in the direction of miniaturization, high sensitivity and high precision, making it possible to apply differential pressure sensors in the fields of medical treatment, aerospace, etc. where it is necessary to measure weak differential pressure accurately.

Sensor packaging technology directly affects the size and performance of differential pressure sensors, and it is therefore highly desirable to provide a new differential pressure sensor packaging structure.

SUMMERY OF THE UTILITY MODEL

The embodiment of the utility model provides a differential pressure sensor aims at reducing differential pressure sensor's encapsulation size, realizes differential pressure sensor's miniaturization.

In a first aspect, an embodiment of the present invention provides a differential pressure sensor, which includes: the shell is provided with a cavity, and a first vent hole and a second vent hole are formed in the shell; the conditioning circuit board is arranged in the cavity and divides the cavity into a first cavity and a second cavity, the first air vent is communicated with the first cavity, the second air vent is communicated with the second cavity, and a through hole communicated with the first cavity and the second cavity is formed in the conditioning circuit board; the pressure chip is arranged in the first cavity, is fixed on the conditioning circuit board and is arranged corresponding to the through hole, so that the pressure of the second cavity can be transmitted to the pressure chip through the through hole, and the pressure chip is electrically connected with the conditioning circuit board.

According to the utility model discloses aforementioned embodiment of first aspect, the pressure chip passes through the silica gel bonding with the conditioning circuit board and fixes.

According to any preceding implementation of the first aspect of the invention, further comprising: the base member, be provided with the logical groove of intercommunication first cavity and second cavity on the base member, the conditioning circuit board is located on the base member and is covered logical groove.

According to any of the preceding embodiments of the first aspect of the present invention, the device further comprises a connecting member, wherein a first end of the connecting member is electrically connected to the conditioning circuit board, and a second end of the connecting member extends out of the housing; the base body is connected with the connecting piece; or; the base body and the connecting piece are integrally formed.

According to the utility model discloses any preceding embodiment of first aspect, the base member is provided with first recess and second recess on the face of first cavity, and the size of first recess is greater than the second recess, and the size of second recess is greater than logical groove, and the second recess sets up in the bottom surface of first recess, leads to the groove and sets up in the bottom surface of second recess, and the conditioning circuit board sets up in the second recess, and the first end of connecting piece sets up in the bottom surface of first recess.

According to any preceding implementation manner of the first aspect of the present invention, the housing includes a first housing and a second housing, the first housing and the second housing are respectively located on two sides of the substrate in the thickness direction and are all connected with the substrate, the conditioning circuit board and the first housing form a first cavity, the substrate, the conditioning circuit board and the second housing form a second cavity, the first vent is disposed on the first housing, and the second vent is disposed on the second housing.

According to the utility model discloses any preceding embodiment of first aspect, first casing is provided with first location step, and the second casing is provided with second location step, the both ends of base member thickness direction respectively with first location step and second location step accordant connection.

According to any of the preceding embodiments of the first aspect of the present invention, the first housing and the second housing are both bonded and fixed to the base member.

According to any of the foregoing embodiments of the first aspect of the present invention, a first circular truncated cone is disposed outside the first housing, a smaller diameter end of the first circular truncated cone deviates from the first housing, and the first vent hole penetrates through the first circular truncated cone; the second round platform is arranged outside the second shell, the smaller diameter end of the second round platform deviates from the second shell, and the second air vent penetrates through the second round platform.

According to any of the preceding embodiments of the first aspect of the present invention, the axial direction of the first vent and the second vent is parallel to the surface of the base.

The embodiment of the utility model provides a differential pressure sensor, which comprises an outer shell, conditioning circuit board and pressure chip, pressure chip is fixed in conditioning circuit board and sets up corresponding to the through-hole, can experience the pressure differential between first cavity and the second cavity and turn into pressure differential signal output with it through pressure chip, conditioning circuit board can take care of the pressure differential signal of pressure chip output, pressure chip and conditioning circuit board pile up the setting in the thickness direction, pile up encapsulation mode simple structure, the cost is lower, and can reduce differential pressure sensor's encapsulation size, realize differential pressure sensor's miniaturization, thereby can satisfy the medical treatment, the user demand in fields such as aerospace.

Drawings

Other features, objects and advantages of the invention will become apparent from the following detailed description of non-limiting embodiments thereof, when read in conjunction with the accompanying drawings, in which like reference characters designate the same or similar parts throughout the figures thereof, and which are not to scale.

Fig. 1 is a schematic structural diagram of a differential pressure sensor according to an embodiment of the present invention;

fig. 2 shows a cross-sectional view of a differential pressure sensor provided by an embodiment of the present invention;

fig. 3 shows an exploded view of a differential pressure sensor provided by an embodiment of the present invention;

fig. 4 is a schematic structural diagram of a differential pressure sensor substrate according to an embodiment of the present invention;

fig. 5 shows a cross-sectional view of a differential pressure sensor base provided by an embodiment of the present invention;

fig. 6 shows a cross-sectional view of a differential pressure sensor first housing provided by an embodiment of the present invention;

fig. 7 shows a cross-sectional view of a second housing of a differential pressure sensor provided by an embodiment of the present invention.

Description of reference numerals:

e-a first cavity; f-a second cavity;

10-a first housing; 101-a first vent; 102-a first positioning step; 110-a first truncated cone;

20-a pressure chip;

30-a conditioning circuit board; 301-a through hole;

40-a substrate; 401-through slots; 402-a first groove; 403-a second groove;

50-a connector;

60-a second housing; 601-a second vent; 602-a second positioning step; 610-a second circular truncated cone.

Detailed Description

The features and exemplary embodiments of various aspects of the present invention will be described in detail below, and in order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention. It will be apparent to one skilled in the art that the present invention may be practiced without some of these specific details. The following description of the embodiments is merely intended to provide a better understanding of the invention by illustrating examples of the invention.

It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.

Referring to fig. 1 to 3, fig. 1 is a schematic structural diagram of a differential pressure sensor according to an embodiment of the present invention; fig. 2 shows a cross-sectional view of a differential pressure sensor provided by an embodiment of the present invention; fig. 3 shows an explosion diagram of a differential pressure sensor according to an embodiment of the present invention.

The embodiment of the utility model provides a differential pressure sensor, including shell, conditioning circuit board 30 and pressure chip 20. The shell is provided with a cavity, and a first vent 101 and a second vent 601 are arranged on the shell; the conditioning circuit board 30 is arranged in the cavity and divides the cavity into a first cavity E and a second cavity F, the first air vent 101 is communicated with the first cavity E, the second air vent 601 is communicated with the second cavity F, and a through hole 301 communicated with the first cavity E and the second cavity F is arranged on the conditioning circuit board 30; the pressure chip 20 is disposed in the first cavity E, the pressure chip 20 is fixed to the conditioning circuit board 30 and disposed corresponding to the through hole 301, so that the pressure of the second cavity F can be transmitted to the pressure chip 20 through the through hole 301, and the pressure chip 20 is electrically connected to the conditioning circuit board 30.

The embodiment of the utility model provides a differential pressure sensor, first blow vent 101, second blow vent 601 are used for making first cavity E, second cavity F and the environment intercommunication that awaits measuring respectively, can feel the pressure differential between first cavity E and the second cavity F and turn into pressure differential signal output with it through pressure chip 20, and conditioning circuit board 30 can condition the pressure differential signal of pressure chip 20 output.

It should be noted that the conditioning function of the conditioning circuit board 30 is not specifically limited in the present application, and for example, the conditioning circuit board 30 may be used to amplify the output signal of the pressure chip 20, set the zero and full-scale outputs of the differential pressure sensor, or correct the linearity and temperature drift of the sensor, so as to improve the accuracy of the sensor.

According to the embodiment of the utility model provides a differential pressure sensor, pressure chip 20 are fixed in conditioning circuit board 30 and set up corresponding to through-hole 301, then pressure chip 20 and conditioning circuit board 30 pile up the setting on thickness direction, pile up encapsulation mode simple structure, and the cost is lower, and can reduce differential pressure sensor's encapsulation size, realize differential pressure sensor's miniaturization to can satisfy the user demand in fields such as medical treatment, aerospace.

The embodiment of the utility model provides a differential pressure sensor can be applied to in the breathing machine. In modern clinical medicine, a breathing machine is a medical device capable of preventing and treating respiratory failure, can play a role in reducing complications and saving and prolonging the life of a patient, and occupies a very important position in the field of modern medicine. In a respirator, a differential pressure sensor is mainly used for converting airway pressure into a micro-differential signal, transmitting a measurement result to a processor to make inspiration and expiration judgment, and then sending an instruction to control an air inlet pump by a processing circuit to increase or decrease the pressure of a pipeline.

In some optional embodiments, the pressure chip 20 may be a Micro-Electro-Mechanical System (MEMS) pressure chip 20, which has the advantages of miniaturization, low power consumption, low cost, good uniformity, and convenience for mass production. The pressure chip 20 includes a sensing film and a resistor engraved on the sensing film and having a piezoresistive effect, wherein when the sensing film is pressed, the magnitude of the resistor changes, thereby causing a corresponding change in the output voltage.

Alternatively, to facilitate the mounting and electrical connection of the pressure chip 20, the back side of the pressure chip 20 faces the through hole 301.

In some alternative embodiments, the conditioning Circuit board 30 may be an Integrated Circuit (ASIC) chip, which has a small size and high communication efficiency.

The pressure chip 20 is fixed on the conditioning circuit board 30, and in some alternative embodiments, the pressure chip 20 and the conditioning circuit board 30 may be bonded by silicone; the thermal expansion coefficients of the silica gel and the pressure chip 20 are similar, the deformation of the silica gel and the pressure chip is consistent when the pressure chip works in a high-temperature environment, the thermal stress is small, and the temperature drift and the time drift stability of the differential pressure sensor can be guaranteed.

Optionally, a silicone rubber with shore a hardness less than 40 may be selected, and such a silicone rubber has greater elasticity after being cured, so that residual stress generated in the process of packaging the pressure chip 20 is very small, and the differential pressure sensor can maintain good stability for a long time.

Certainly, the fixing material between the pressure chip 20 and the conditioning circuit board 30 is not limited to silica gel, and other colloids such as solid crystal glue may be selected, or the pressure chip 20 and the conditioning circuit board 30 are fixed by clamping, and the like, and the protection scope of the present application is also included.

In some optional embodiments, to facilitate the placing of the conditioning circuit board 30 and the pressure chip 20 in the cavity, the housing may include a first casing 10 and a second casing 20, when packaged, the first casing 10 and the second casing 20 may be respectively located at two sides of the conditioning circuit board 30 in the thickness direction, the conditioning circuit board 30 and the first casing 10 form a first cavity E, the conditioning circuit board 30 and the second casing 20 form a second cavity F, the first air vent 101 is disposed in the first casing 10, and the second air vent 601 is disposed in the second casing 20.

In some optional embodiments, the differential pressure sensor provided in the embodiments of the present invention may further include a connecting member 50, a first end of the connecting member 50 is electrically connected to the conditioning circuit board 30, a second end of the connecting member extends out of the housing, and the connecting member 50 is used to electrically connect the differential pressure sensor to the outside.

The present application is not limited to the specific structure of the connector 50. Optionally, the connecting element 50 may be a pin, and the pin may be a plug-in pin or a patch pin, which may be specifically selected according to actual use requirements, and all of which are within the protection scope of the present application.

Referring to fig. 4 and 5, fig. 4 is a schematic structural diagram of a differential pressure sensor substrate according to an embodiment of the present invention; fig. 5 shows a cross-sectional view of a differential pressure sensor substrate according to an embodiment of the present invention.

In some optional embodiments, in order to facilitate the volume production of differential pressure sensors, the differential pressure sensor provided in the embodiments of the present invention may further include a base 40, the base 40 is provided with a through groove 401 communicating the first cavity E and the second cavity F, and the conditioning circuit board 30 is disposed on the base 40 and covers the through groove 401.

Alternatively, the first end of the connector 50 is fixedly connected to the base 40, and the first end of the connector 50 may be electrically connected to the conditioning circuit board 30 through a wire.

Optionally, the base 40 can be made of plastic, the base 40 and the connecting piece 50 can be integrally formed, the fixing is reliable, mass production and manufacturing are convenient, and the cost is low. Of course, the connecting member 50 and the base 40 may be made separately and fixed by bonding or the like, and is also within the scope of the present application.

The number of the connection members 50 is not particularly limited in the present application. Optionally, the number of the connecting members 50 is multiple, the connecting members 50 may be distributed on two sides of the width direction of the base 40, and the connecting members 50 on one side may be disposed at equal intervals along the length direction of the base 40.

Optionally, to facilitate distinguishing between connectors 50 with different functions, a notch, a number, or the like, may be provided at the second end of the connector 50.

In some optional embodiments, to facilitate the installation of the conditioning circuit board 30, a first groove 402 and a second groove 403 may be disposed on a surface of the base 40 facing the first cavity E, the size of the first groove 402 is larger than that of the second groove 403, the size of the second groove 403 is larger than that of the through groove 401, the second groove 403 is disposed on a bottom surface of the first groove 402, the through groove 401 is disposed on a bottom surface of the second groove 403, the conditioning circuit board 30 is disposed on the second groove 403, and the first end of the connecting member 50 is disposed on a bottom surface of the first groove 402.

Referring to fig. 6 and 7 together, fig. 6 is a cross-sectional view of a first housing of a differential pressure sensor according to an embodiment of the present invention; fig. 7 shows a cross-sectional view of a second housing of a differential pressure sensor provided by an embodiment of the present invention.

In some optional embodiments, the differential pressure sensor provided in the embodiments of the present invention, during packaging, the first casing 10 and the second casing 20 may be respectively located at two sides of the thickness direction of the base 40 and are both connected to the base 40, and the base 40, the conditioning circuit board 30 and the first casing 10 form a first cavity E, and the base 40, the conditioning circuit board 30 and the second casing 20 form a second cavity F.

The present application is not particularly limited to the fixing manner of the base 40 to the first casing 10 and the second casing 20, and the base 40 may be fixed to the first casing 10 and the second casing 20 by, for example, adhesion. Optionally, the first casing 10 and the second casing 20 are fixed to the base 40 by glue with shore D hardness greater than 80, which has good adhesion and can withstand the highest air pressure required for sensing.

Alternatively, the first housing 10 may be provided with a first positioning step 102, the second housing 20 may be provided with a second positioning step 602, and both ends of the base 40 in the thickness direction may be respectively matched and connected with the first positioning step 102 and the second positioning step 602. The base body 40 is matched with the first shell 10 and the second shell 20 through steps, so that the production efficiency can be improved, and the assembly size precision is ensured; in addition, the step matching can facilitate the gluing process, ensure the tightness of the assembly and improve the appearance of the product.

Of course, the positioning manner between the base 40 and the housing is not limited to this, and for example, the positioning between the base 40 and the first and

second housings

10 and 20 may also be realized by positioning pins, which is also within the protection scope of the present application.

In some optional embodiments, a first circular truncated cone 110 may be disposed outside the first housing 10, a smaller diameter end of the first circular truncated cone 110 faces away from the first housing 10, and the first air vent 101 penetrates through the first circular truncated cone 110, so that the first circular truncated cone 110 may form an air nozzle joint, which facilitates installation and connection of an air tube. Correspondingly, a second circular truncated cone 610 can also be arranged outside the second housing 20, the smaller diameter end of the second circular truncated cone 610 deviates from the second housing 20, and the second air vent 601 penetrates through the second circular truncated cone 610, so that the second circular truncated cone 610 forms an air nozzle joint.

Optionally, the axial directions of the first vent 101 and the second vent 601 may be both parallel to the plate surface of the substrate 40, that is, parallel to the sensing film of the pressure chip 20, so as to avoid that the airflow entering the first cavity E and the second cavity F is directly opposite to the sensing film, thereby improving the measurement accuracy of the differential pressure sensor.

The material of the housing is not particularly limited in this application. The material of the first casing 10 and the second casing 20 may be, for example, 70% polyhexamethylene adipamide and 30% glass fiber, 70% polytetramethylene terephthalate and 30% glass fiber, ceramic or epoxy resin, and the first casing 10 and the second casing 20 manufactured by using these materials have high strength, good toughness, and excellent mechanical properties.

In accordance with the embodiments of the present invention as set forth above, these embodiments do not set forth all of the details nor limit the invention to the specific embodiments described. Obviously, many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the invention and its practical application, to thereby enable others skilled in the art to best utilize the invention and its various embodiments with various modifications as are suited to the particular use contemplated. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. A differential pressure sensor, comprising:

the shell is provided with a cavity, and a first vent hole and a second vent hole are formed in the shell;

the conditioning circuit board is arranged in the cavity and divides the cavity into a first cavity and a second cavity, the first air vent is communicated with the first cavity, the second air vent is communicated with the second cavity, and a through hole communicated with the first cavity and the second cavity is formed in the conditioning circuit board;

the pressure chip is arranged in the first cavity, fixed on the conditioning circuit board and arranged corresponding to the through hole, so that the pressure of the second cavity can be transmitted to the pressure chip through the through hole, and the pressure chip is electrically connected with the conditioning circuit board.

2. The differential pressure sensor of claim 1, wherein the pressure chip and the conditioning circuit board are secured by silicone adhesive.

3. The differential pressure sensor of claim 1, further comprising:

the conditioning circuit board is arranged on the base body and covers the through groove.

4. The differential pressure sensor of claim 3, further comprising a connector, a first end of the connector being electrically connected to the conditioning circuit board, a second end of the connector extending out of the housing;

the base body is connected with the connecting piece; or; the base body and the connecting piece are integrally formed.

5. The differential pressure sensor according to claim 4, wherein a plate surface of the base body facing the first cavity is provided with a first groove and a second groove, the first groove is larger in size than the second groove, the second groove is larger in size than the through groove, the second groove is provided on a bottom surface of the first groove, the through groove is provided on a bottom surface of the second groove, the conditioning circuit board is provided on the second groove, and the first end of the connecting member is provided on a bottom surface of the first groove.

6. The differential pressure sensor according to claim 3 or 4, wherein the housing includes a first housing and a second housing, the first housing and the second housing are respectively located on both sides of the base in the thickness direction and are connected to the base, the conditioning circuit board and the first housing form the first cavity, the base, the conditioning circuit board and the second housing form the second cavity, the first vent is provided in the first housing, and the second vent is provided in the second housing.

7. The differential pressure sensor according to claim 6, wherein the first housing is provided with a first positioning step, the second housing is provided with a second positioning step, and both ends in the thickness direction of the base body are respectively in matching connection with the first positioning step and the second positioning step.

8. The differential pressure sensor of claim 6, wherein the first housing and the second housing are each adhesively secured to the base.

9. The differential pressure sensor of claim 6, wherein a first boss is disposed outside the first housing, a smaller diameter end of the first boss faces away from the first housing, and the first vent extends through the first boss;

the second round platform is arranged outside the second shell, the smaller diameter end of the second round platform deviates from the second shell, and the second air port penetrates through the second round platform.

10. The differential pressure sensor of claim 9, wherein the first and second vents are each axially parallel to the plate surface of the base.