CN2859488Y

CN2859488Y - A pressure sensor

Info

Publication number: CN2859488Y
Application number: CN 200520127076
Authority: CN
Inventors: 李仁贵; 庄东霖; 王锡文
Original assignee: XINCHEN SCIENCE AND TECHNOLOGY Co Ltd
Current assignee: XINCHEN SCIENCE AND TECHNOLOGY Co Ltd
Priority date: 2005-09-29
Filing date: 2005-09-29
Publication date: 2007-01-17
Anticipated expiration: 2015-09-29

Abstract

This utility model relates to a pressure sensor, which have the effect of temperature compensation and is applyed to measure acid or alkalescence liquid pressure. like ebonite epoxy group resin make of encapsulation structure to protect pressure sensor measureing chip and wire, by which means, pressure sensor has the function of temperature compensation so as to improve its measuring accuracy. Outside of said encapsulation structure may still cover a acid-resisting and alkali-resisting film which make pressure sensor suit for measuring acid or alkalescence liquid pressure.

Description

A kind of pressure transducer

Technical field

The utility model relates to a kind of pressure transducer, instigates pressure transducer to have effect temperature compensation especially and is applicable to the pressure sensor package structure of measuring acidity or akaline liquid.

Background technology

Wirking pressure sensor 10 as shown in Figure 1 is a kind of pressure transducers that do not have the packaging protection structure, is made up of jointly a pressure-sensing chip 20 and a circuit board 30.The pressure-sensing chip 20 of this pressure transducer 10; under the naked state that does not have the packaging protection structure; can export pressure simulation signal or the digital signal that measures in response to the pressure effect; and borrow meticulous metal wire 21 to join the circuit of circuit board 30 (wire bond PCB) to; with measured pressure simulation signal or digital signal output; with be transferred to micro processor (MCU) calculation via circuit board 30, to be converted into measured pressure measuring value.

During use; the pressure-sensing chip 20 of this pressure transducer 10 and metal wire 21 all are not subjected to the protection of encapsulating structure; so gas or fluid pressure can act directly on pressure-sensing chip 20 and the metal wire 21; except easy build-up of pressure sensor chip 20 and metal wire 21 damages; also inapplicable measurement acidity or akaline liquid; because when touching acidity or akaline liquid, pressure-sensing chip 20 and metal wire 21 can be corroded at once.

Especially, experimental data figure according to the temperature variation and the pressure survey output valve of this pressure transducer 10 shown in Figure 2, show the pressure survey output valve of pressure-sensing chip 20 of this pressure transducer 10 and the relation between the temperature variation, be nonlinear relationship.So the mortal wound of this pressure transducer 10 is vulnerable to the influence of temperature change of external environment and can produces corresponding pressure survey output valve error when just being to use.Owing to be nonlinear relationship between pressure survey output valve and the temperature variation, be difficult for carrying out temperature compensation and proofread and correct, measured pressure survey output valve is difficult to improve precision.

In order to improve the shortcoming that does not have the encapsulating structure protection from the pressure-sensing chip 20 and the metal wire 21 of wirking pressure sensor 10; another kind of wirking pressure sensor 11 as shown in Figure 3 then selects for use flexible glue materials such as comprising silica gel to constitute the encapsulating structure 25 of packaging protection pressure-sensing chip 20 and metal wire 21.During use; the pressure-sensing chip 20 of this pressure transducer 11 and metal wire 21 are by the protection of encapsulating structure 25; really can avoid gas or fluid pressure to act directly on pressure-sensing chip 20 and the metal wire 21, so can prolong the serviceable life of this pressure transducer 11.

But, experimental data figure according to the temperature variation and the pressure survey output valve of this pressure transducer 11 shown in Figure 4, show the pressure survey output valve of pressure-sensing chip 20 of this pressure transducer 11 and the relation between the temperature variation, still be nonlinear relationship.So, even this pressure transducer 11 uses flexible glue to constitute encapsulating structure 25, still be vulnerable to the influence of temperature change of external environment and can produce corresponding pressure survey output valve error, except still being difficult for carrying out the temperature compensation correction, constitute the shortcoming of encapsulating structure 25 with flexible glue materials such as silica gel, also should not touch acidic liquid or akaline liquid for a long time, so still be not suitable for the pressure of measuring acidic liquid or akaline liquid.

The utility model content

Therefore, main creation purpose of the present utility model, promptly the shortcoming of using flexible glue to constitute encapsulating structure at existing wirking pressure sensor is improved, and makes pressure transducer have effect temperature compensation, and is applicable to measurement acidity or akaline liquid pressure.

Pressure transducer shown in the utility model; at first use with ebonites such as epoxies and constitute the pressure-sensing chip of protection pressure transducer and the encapsulating structure of metal wire; and encapsulating structure whereby; make to reach between the pressure survey output valve of pressure-sensing chip of pressure transducer and the temperature variation and be the linear changing relation; with so as to facilitating pressure transducer to have effect temperature compensation; the pressure survey output valve error that is produced in the time of can using compensating-pressure transducer to be subjected to the influence of temperature change of external environment is with the measurement precision of adherence pressure sensor.

Less important creation purpose of the present utility model, it is the outside of using the encapsulating structure of ebonite formation at pressure transducer, cover the Teflon film of the acidproof and alkaline-resisting characteristic of one deck tool again, make pressure transducer of the present utility model also be applicable to and measure acidity or akaline liquid pressure.

Another technical scheme of the present utility model provides a kind of double direct plugging-in pressure transducer, have a bilateral pin and a pressure-sensing chip, and this pressure-sensing chip uses the bilateral pin of metal wire and this to constitute and electrically connects, it is characterized in that this pressure-sensing chip and metal wire have the encapsulating structure that constitutes with ebonites such as epoxies.In the outside of described encapsulating structure, can also cover the Teflon film of the acidproof and alkaline-resisting characteristic of one deck tool again, make pressure transducer of the present utility model also be applicable to and measure acidity or akaline liquid pressure.

In addition, the utility model also provides the surface adhesion type pressure transducer, have a bilateral pin and a pressure-sensing chip, and this pressure-sensing chip uses the bilateral pin of metal wire and this to constitute and electrically connects, it is characterized in that this pressure-sensing chip and metal wire have the encapsulating structure that constitutes with ebonites such as epoxies.In the outside of described encapsulating structure, can also cover the Teflon film of the acidproof and alkaline-resisting characteristic of one deck tool again, make pressure transducer of the present utility model also be applicable to and measure acidity or akaline liquid pressure.

Description of drawings

Fig. 1 is the synoptic diagram of wirking pressure sensor.

Fig. 2 is the temperature variation of pressure transducer shown in Figure 1 and the experimental data figure of pressure survey output valve.

Fig. 3 is the synoptic diagram of another kind of wirking pressure sensor.

Fig. 4 is the temperature variation of pressure transducer shown in Figure 3 and the experimental data figure of pressure survey output valve.

Fig. 5 is the synoptic diagram of the pressure transducer shown in the utility model.

Fig. 6 is the temperature variation of pressure transducer shown in Figure 5 and the experimental data figure of pressure survey output valve.

Fig. 7 A and Fig. 7 B are the synoptic diagram of double direct plugging-in (DIP) pressure transducer shown in the utility model.

Fig. 8 A and Fig. 8 B are the synoptic diagram of the surface adhesion type shown in the utility model (STM) pressure transducer.

The accompanying drawing sign

10 ... pressure transducer 11 ... pressure transducer

15 ... pressure transducer 16 ... double direct plugging-in pressure transducer

17 ... surface adhesion type pressure transducer 18 ... bilateral pin

20 ... pressure-sensing chip 21 ... metal wire

25 ... encapsulating structure 30 ... circuit board

40 ... encapsulating structure 50 ... the Teflon film

Embodiment

Please refer to Fig. 5, the pressure transducer 15 that the utility model disclosed, form jointly by a pressure-sensing chip 20 and a circuit board 30, wherein, the technology that this pressure-sensing chip 20 borrows use metal wire 21 to join circuit board 30 (wire bond PCB) to is with the circuit formation electric connection of circuit board 30.

Pressure transducer 15 shown in the utility model; for the metal wire 21 that makes pressure-sensing chip 20 can bear high pressure and not fragile; use encapsulates the metal wire 21 of pressure transducer 15 with epoxy ebonites such as (epoxy), and constitutes the encapsulating structure 40 of protection pressure-sensing chip 20 and metal wire 21.

When the utility model constitutes the encapsulating structure 40 of protection pressure transducer 15 and metal wire 21 with ebonite; experimental data figure according to temperature variation shown in Figure 6 and pressure survey output valve; show the pressure survey output valve and the relation that is subjected to the influence of temperature change of external environment of the pressure-sensing chip 20 of pressure transducer 15 of the present utility model, reach linear.

During use, the pressure-sensing chip 20 of pressure transducer 15 of the present utility model can be exported pressure simulation signal or the digital signal that measures in response to the pressure effect, and borrow the transmission of metal wire 21 with circuit board 30, measured pressure simulation signal or digital signal are outputed to micro processor (MCU) calculation, to be converted into measured pressure measuring value.

Simultaneously, borrow linear between utilization temperature variation shown in Figure 6 and the pressure survey output valve, the pressure survey output valve error that influence of temperature change produced that can computing compensating-pressure transducer 15 be subjected to external environment, make pressure transducer 15 of the present utility model have effect temperature compensation, but the measurement precision of adherence pressure sensor 15.

In addition, pressure transducer 15 of the present utility model is in the outside of the encapsulating structure 40 that constitutes with ebonite, can cover the Teflon film 50 of the acidproof and alkaline-resisting characteristic of one deck tool again, with isolated and prevent encapsulating structure 40 to be subjected to aqueous vapor or Acidity of Aikalinity corroded by liquid and go bad, make pressure transducer 15 of the present utility model applicable to measurement acidity or akaline liquid pressure.

Please refer to Fig. 7 and Fig. 8, second kind of specific embodiment of the present utility model, be to borrow existing encapsulation technology commonly used, foregoing pressure-sensing chip 20, metal wire 21, encapsulating structure 40 and 50 integration of Teflon film are set as the pressure transducer with bilateral pin 18, comprise double direct plugging-in (DIP) pressure transducer 16 that can be set as shown in Figure 7, or be set as surface adhesion type (STM) pressure transducer 17 as shown in Figure 8.

Claims

1, a kind of pressure transducer, comprise a pressure-sensing chip and a circuit board, and this pressure-sensing chip uses the circuit of metal wire and this circuit board to constitute and electrically connects, and it is characterized in that, this pressure-sensing chip and metal wire have the encapsulating structure that constitutes with the ebonite encapsulation.

2, pressure transducer as claimed in claim 1 is characterized in that, this pressure-sensing chip and metal wire have the encapsulating structure that constitutes with the epoxy encapsulation.

3, pressure transducer as claimed in claim 1 or 2 is characterized in that, the outside of this encapsulating structure also covers one deck Teflon film.

4, a kind of double direct plugging-in pressure transducer, have a bilateral pin and a pressure-sensing chip, and this pressure-sensing chip uses the bilateral pin of metal wire and this to constitute and electrically connects, and it is characterized in that, this pressure-sensing chip and metal wire have the encapsulating structure that constitutes with the ebonite encapsulation.

5, double direct plugging-in pressure transducer as claimed in claim 4 is characterized in that, this pressure-sensing chip and metal wire have the encapsulating structure that constitutes with the epoxy encapsulation.

6, as claim 4 or 5 described double direct plugging-in pressure transducers, it is characterized in that the outside of this encapsulating structure also covers one deck Teflon film.

7, a kind of surface adhesion type pressure transducer, have a bilateral pin and a pressure-sensing chip, and this pressure-sensing chip uses the bilateral pin of metal wire and this to constitute and electrically connects, and it is characterized in that, this pressure-sensing chip and metal wire have the encapsulating structure that constitutes with the ebonite encapsulation.

8, surface adhesion type pressure transducer as claimed in claim 7 is characterized in that, this pressure-sensing chip and metal wire have the encapsulating structure that constitutes with the epoxy encapsulation.

9, as claim 7 or 8 described surface adhesion type pressure transducers, it is characterized in that the outside of this encapsulating structure also covers one deck Teflon film.