CN219736666U - Improved pressure sensor - Google Patents

Abstract

The utility model provides an improved pressure sensing device, which comprises a microcontroller, a micro-electromechanical system pressure sensing integrated circuit and an integrated circuit end temperature coefficient thermistor; the microcontroller detects the temperature of an integrated circuit end of the MEMS pressure sensing integrated circuit through the temperature coefficient thermistor of the integrated circuit end; the MEMS pressure sensing integrated circuit transmits a pressure sensing signal to the microcontroller; the microcontroller corrects the pressure sensing signal using a temperature pressure equation based on the integrated circuit end temperature.

Description

Improved pressure sensor

Cross Reference to Related Applications

The present utility model claims priority from taiwan patent application No.111205259 filed 20 at 05 month 2022, which is incorporated by reference for all purposes as if fully set forth herein.

Technical Field

The present utility model relates to a pressure sensing device, and more particularly, to an improved pressure sensing device.

Background

The related art pressure sensing device is used for sensing the pressure of liquid or gas in a pipeline of equipment, so as to directly display the pressure change of various process links, and further control related parameters or conditions to maintain the reliability and safety of production operation, so that the related art pressure sensing device is a common measuring instrument nowadays and is widely applied to various technical fields and equipment.

A related art pressure sensing device utilizes a related art MEMS pressure sensing integrated circuit to perform pressure sensing; however, the mems pressure sensing integrated circuit of the related art is susceptible to temperature due to temperature cycling during the process, and cannot accurately indicate the accurate pressure value during the process temperature variation. For example, for air, the Ideal Gas equation (Ideal Gas Law), pv=nrt, describes a positive pressure-temperature-related change; however, when the temperature of the liquid is close to the evaporation temperature, the detected liquid is in liquid-gas phase, which results in distorted pressure values, and this problem needs to be solved.

Disclosure of Invention

In order to solve the above-mentioned problems, an object of the present utility model is to provide an improved pressure sensing device.

To achieve the above object, the improved pressure sensing device of the present utility model comprises: a microcontroller; a micro-electromechanical system pressure sensing integrated circuit electrically connected to the microcontroller; and an integrated circuit end temperature coefficient thermistor electrically connected to the microcontroller, wherein the microcontroller is configured to detect an integrated circuit end temperature of the MEMS pressure sensing integrated circuit through the integrated circuit end temperature coefficient thermistor; the MEMS pressure sensing integrated circuit is configured to transmit a pressure sensing signal to the microcontroller; the microcontroller is configured to correct the pressure sensing signal using a temperature pressure equation based on the integrated circuit side temperature.

The utility model has the effect of improving the accuracy when the MEMS pressure sensing integrated circuit is used for sensing pressure.

For a further understanding of the technology, means, and efficacy of the present utility model, reference should be made to the following detailed description of the utility model and to the accompanying drawings, which are included to provide a further understanding of the utility model, and to the specific features and aspects of the utility model, however, are given by way of illustration and not limitation.

Drawings

FIG. 1 is a block diagram of a first embodiment of an improved pressure sensing device of the present utility model;

FIG. 2 is a block diagram of a second embodiment of an improved pressure sensing device of the present utility model;

FIG. 3 is an exploded perspective view of an improved pressure sensor device according to the present utility model;

FIG. 4 is a schematic perspective view of an improved pressure sensor according to the present utility model;

FIG. 5 is a schematic side sectional view of an improved pressure sensing device of the present utility model;

FIG. 6 is a graph showing the relationship between the digitized amplified pressure sensing signal and temperature according to one embodiment of the present utility model;

FIG. 7 is a timing diagram of an embodiment of the digitized amplified pressure and temperature signals according to the present utility model;

FIG. 8 is a graph of digital values versus temperature for a digitized and linearized pressure sense amp signal, a linearized temperature coefficient thermistor of an integrated circuit according to one embodiment of the present utility model;

FIG. 9 is a graph showing the relationship between the digitized pressure sensing amplified signal and the digital value of the temperature coefficient thermistor of the integrated circuit according to an embodiment of the present utility model;

FIG. 10 is a graph of the digitized and linearized pressure sense amp signal, the linearized digital value of the temperature coefficient thermistor of the integrated circuit versus temperature for another embodiment of the present utility model;

FIG. 11 is a graph showing the relationship between the digitized pressure sensing amplified signal and the digital value of the temperature coefficient thermistor of the integrated circuit according to another embodiment of the present utility model;

wherein, the reference numerals:

1: improved pressure sensor

3 fixing seat board

4 apparatus

12 microcontroller

Pressure sensing integrated circuit for micro-electromechanical system

16-integrated circuit end temperature coefficient thermistor

18 pressure sensing signal

20 auxiliary temperature coefficient thermistor

Operational amplifier 22

24 key set

26 light emitting diode display

28 output interface

30 connecting holes

32 lower oil chamber

34 diaphragm

36 pressure sense amplified signal

38 upper oil chamber

40 pipeline

42 first position

44 second position

110 pipe joint

701 Curve

702 curve

801 straight line

802: straight line.

Detailed Description

In the description, numerous specific details are provided to provide a thorough understanding of particular embodiments of the utility model; however, it will be apparent to one skilled in the art that the present utility model may be practiced without one or more of these specific details; in other instances, well-known details are not shown or described in order to avoid obscuring the utility model. The technical content and detailed description of the present utility model are described below with reference to the drawings:

referring to fig. 1, a block diagram of a first embodiment of an improved pressure sensing device 1 according to the present utility model is shown. An improved pressure sensing device 1 of the present utility model comprises a micro-controller 12, a micro-electro-mechanical system (micro electro mechanical system, commonly referred to as MEMS) pressure sensing integrated circuit (integrated circuit, commonly referred to as IC) 14 and an integrated circuit side temperature coefficient thermistor (temperature coefficient thermistor) 16, wherein the micro-controller 12 is electrically connected to the MEMS pressure sensing integrated circuit 14 and the integrated circuit side temperature coefficient thermistor 16. The pressure sensing device of the present utility model may also be referred to as a pressure sensor.

The integrated circuit end temperature coefficient thermistor 16 is a negative temperature coefficient (negative temperature coefficient, commonly referred to as NTC) thermistor or a positive temperature coefficient (positive temperature coefficient, commonly referred to as PTC) thermistor, or a paired combination of a negative temperature coefficient thermistor and a positive temperature coefficient thermistor. The microcontroller 12 is configured to detect an integrated circuit side temperature of the mems pressure sensing integrated circuit 14 via the integrated circuit side temperature coefficient thermistor 16, and the mems pressure sensing integrated circuit 14 is configured to pressure sense a medium (e.g., liquid or gas) to be measured within a circuit (not shown in fig. 1) of a device (not shown in fig. 1) via a pressure sensing component (not shown in fig. 1) to generate a pressure sensing signal 18 and transmit the pressure sensing signal 18 to the microcontroller 12. Next, after the microcontroller 12 knows the ic side temperature and receives the pressure sensing signal 18, the microcontroller 12 is configured to correct the pressure sensing signal 18 using a temperature pressure equation based on the ic side temperature, as described in detail below. Furthermore, the correction referred to herein may also be referred to as compensation.

Referring to fig. 2, a block diagram of a second embodiment of an improved pressure sensing device 1 according to the present utility model is shown; the elements shown in fig. 2 are identical to those shown in fig. 1, and thus, a description thereof will not be repeated here for the sake of brevity. The improved pressure sensing device 1 further comprises an auxiliary temperature coefficient thermistor 20, an operational amplifier 22, a key set 24, a light emitting diode display 26 and an output interface 28, wherein the microcontroller 12 is electrically connected to the auxiliary temperature coefficient thermistor 20, the operational amplifier 22, the key set 24, the light emitting diode display 26 and the output interface 28, and the operational amplifier 22 is further electrically connected to the mems pressure sensing integrated circuit 14. The improved pressure sensor 1 adopts a 4-20 mA signal transmission mode and an NPN/PNP connection mode, and the output interface 28 is an IO-Link output interface. Furthermore, the present utility model may also include a plurality of the output interfaces 28.

The auxiliary temperature coefficient thermistor 20 is a negative temperature coefficient thermistor or a positive temperature coefficient thermistor, or a pairing combination of a negative temperature coefficient thermistor and a positive temperature coefficient thermistor. In a second embodiment, as shown in FIG. 2, the MEMS pressure sensing integrated circuit 14 is configured to transmit the pressure sensing signal 18 to the operational amplifier 22, then the operational amplifier 22 is configured to amplify the pressure sensing signal 18 to obtain a pressure sensing amplified signal 36, then the operational amplifier 22 is configured to transmit the pressure sensing amplified signal 36 to the microcontroller 12; after the microcontroller 12 knows the IC side temperature and receives the pressure sense amp signal 36, the microcontroller 12 is configured to correct the pressure sense amp signal 36 using a temperature pressure equation based on the IC side temperature, as described in more detail below. Furthermore, in another embodiment of the present utility model, the integrated circuit end temperature coefficient thermistor 16 and the auxiliary temperature coefficient thermistor 20 may be both negative temperature coefficient thermistor or positive temperature coefficient thermistor, or one may be negative temperature coefficient thermistor and the other may be positive temperature coefficient thermistor.

Fig. 3 is a schematic perspective exploded view of the improved pressure sensing device 1 of the present utility model, fig. 4 is a schematic perspective combined view of the improved pressure sensing device 1 of the present utility model, and fig. 5 is a schematic side sectional view of the improved pressure sensing device 1 of the present utility model; the elements shown in fig. 3, 4 and 5 are identical to those shown in fig. 2, and thus, the description thereof will not be repeated here for the sake of brevity. Referring to fig. 3, 4 and 5, the improved pressure sensing device 1 is applied to a device 4, the improved pressure sensing device 1 further comprises an upper oil chamber 38, a lower oil chamber 32, a diaphragm 34, a pipe joint 110 and a fixing seat plate 3, the device 4 and the fixing seat plate 3 define a connecting hole 30, and the device 4 comprises a pipeline 40.

As shown in fig. 5, the lower oil chamber 32 is connected to the upper oil chamber 38, and the diaphragm 34 is disposed in the lower oil chamber 32; the mems pressure sensing integrated circuit 14 and the ic-side temperature coefficient thermistor 16 are disposed on the upper oil chamber 38, for example, at a first location 42 shown in fig. 5; the auxiliary temperature coefficient thermistor 20 is disposed in the lower chamber 32, for example, in a second position 44 shown in fig. 5. As shown in fig. 3, 4 and 5, the stationary seat plate 3 is fixedly provided on the apparatus 4; the pipe joint 110 is connected to the pipe 40 of the apparatus 4 through the connection hole 30, so that the improved pressure sensing device 1 performs pressure sensing on the medium (such as liquid or gas) to be measured in the pipe 40.

Please refer to fig. 6, which is a diagram illustrating an embodiment of the digitized pressure sensing amplification signal 36 versus temperature according to the present utility model, wherein the digitized pressure sensing amplification signal 36 is converted into a digital value by the microcontroller 12 to obtain the digitized pressure sensing amplification signal 36, and the digitized pressure sensing amplification signal 36 of fig. 6 is not yet corrected by the microcontroller 12. In fig. 6, the vertical axis is a digital value, the horizontal axis is temperature (in degrees celsius), the solid curve of fig. 6 (having hysteresis) is the original digitized pressure sense amplified signal 36, and the dotted line of fig. 6 is the digitized and linearized pressure sense amplified signal 36 (having the equation: y= -2.2183 x+2362.5). As can be seen from fig. 6, the digitized and linearized pressure sense amp signal 36 is inversely related to temperature; that is, the higher the temperature, the lower the digitized and linearized pressure sense amp signal 36; the lower the temperature, the higher the digitized and linearized pressure sense amp signal 36; however, for detecting a substantially constant pressure source, the pressure sense amp signal 36 should also be maintained substantially constant and unaffected by temperature, and the present utility model is directed to correcting this temperature-affected problem.

Referring to fig. 7, which is a timing diagram of an embodiment of the digitized pressure sensing amplification signal 36 and temperature according to the present utility model, the digitized pressure sensing amplification signal 36 is converted into a digital value by the microcontroller 12 to obtain the digitized pressure sensing amplification signal 36, and the digitized pressure sensing amplification signal 36 of fig. 7 is not yet corrected by the microcontroller 12. In fig. 7, the left axis represents the digital value, the right axis represents the temperature (in degrees celsius), the horizontal axis represents the time (in minutes), the curve 701 represents the digitized amplified signal 36, and the curve 702 represents the temperature. As can also be seen in fig. 7, the digitized pressure sense amp signal 36 (curve 701) is inversely related to temperature (curve 702).

Referring to fig. 8, which is a graph showing the relationship between the digital value and the temperature of the digitized and linearized pressure sense amplifying signal 36 and the linearized temperature coefficient thermistor 16 according to an embodiment of the present utility model, the digitized and linearized pressure sense amplifying signal 36 is converted into a digital value by the microcontroller 12 and linearized to obtain the digitized and linearized pressure sense amplifying signal 36, and the digitized and linearized pressure sense amplifying signal 36 of fig. 8 is not corrected by the microcontroller 12, and the microcontroller 12 detects the resistance value of the temperature coefficient thermistor 16 changed by the temperature change and digitizes and linearizes the resistance value to obtain the digital value of the linearized temperature coefficient thermistor 16, and the temperature coefficient thermistor 16 is a negative temperature coefficient thermistor. In fig. 8, the vertical axis represents a digital value, and the horizontal axis represents temperature (in degrees celsius); line 801 of FIG. 8 represents the digitized and linearized pressure sense amp signal 36, and line 801 of FIG. 8 has the equation: y= -2.2183x+2362.5; the line 802 of fig. 8 represents the digital value of the integrated circuit end temperature coefficient thermistor 16 after linearization, and the line 802 of fig. 8 has the equation: y= -32.68x+2932.7.

As can be seen from fig. 8, the digitized and linearized pressure sense amp signal 36 (line 801, having the equation y= -2.2183x+2362.5) is inversely related to temperature, and the linearized digital value of the temperature coefficient thermistor 16 (line 802, having the equation y= -32.68x+2932.7) is also inversely related to temperature. Therefore, when the temperature rises, the microcontroller 12 detects the digital value of the linearized temperature coefficient thermistor 16 to be reduced, the microcontroller 12 knows that the temperature rises, and the digitized and linearized pressure sense amplifying signal 36 is inversely related to the temperature, so that the digitized and linearized pressure sense amplifying signal 36 will be reduced (but not correct), so that the microcontroller 12 must increase the value of the digitized and linearized pressure sense amplifying signal 36 to know the correct pressure. When the temperature decreases, the microcontroller 12 detects the increase in the digital value of the linearized temperature coefficient thermistor 16, and the microcontroller 12 knows that the temperature decreases, and the digitized and linearized pressure sense amplifying signal 36 is inversely related to the temperature, so that the digitized and linearized pressure sense amplifying signal 36 increases (but is incorrect), so that the microcontroller 12 must decrease the value of the digitized and linearized pressure sense amplifying signal 36 to obtain the correct pressure.

Referring to fig. 9, which is a graph showing the relationship between the digitized amplified signal 36 and the digital value of the ptc thermistor 16 according to an embodiment of the present utility model, the amplified signal 36 is converted into the digital value by the microcontroller 12 to obtain the digitized amplified signal 36, and the digitized amplified signal 36 of fig. 9 is not corrected by the microcontroller 12, and the microcontroller 12 detects the resistance value of the ptc thermistor 16 changed by temperature change and digitizes the resistance value to obtain the digital value of the ptc thermistor 16, and the ptc thermistor 16 is a negative ptc thermistor. In fig. 9, the vertical axis represents the digital value of the digitized amplified signal 36, the horizontal axis represents the digital value of the integrated circuit temperature coefficient thermistor 16, the solid curve of fig. 9 (hysteresis) represents the digitized amplified signal 36, and the dashed line of fig. 9 represents the relationship between the digitized and linearized amplified signal 36 and the linearized digital value of the integrated circuit temperature coefficient thermistor 16 (with temperature pressure equation: y=0.0679x+2163.4).

As can be seen from fig. 9 and the temperature-pressure equation (y=0.0679x+2163.4), if the digital value of the ic-side temperature coefficient thermistor 16 (horizontal axis of fig. 9) is reduced by one unit (one unit represents a temperature rise because the ic-side temperature coefficient thermistor 16 is a negative temperature coefficient thermistor), the digitized and linearized pressure sense amplifying signal 36 is erroneously reduced by 0.0679 units, so that the microcontroller 12 needs to add 0.0679 units to the digitized and linearized pressure sense amplifying signal 36 to obtain the correct pressure. As can be seen from fig. 9 and the temperature-pressure equation (y=0.0679x+2163.4), if the digital value of the ic-side temperature coefficient thermistor 16 (horizontal axis of fig. 9) is increased by one unit (one unit represents a temperature drop because the ic-side temperature coefficient thermistor 16 is a negative temperature coefficient thermistor), the digitized and linearized pressure sense amplifying signal 36 is erroneously increased by 0.0679 units, so that the microcontroller 12 needs to decrease the digitized and linearized pressure sense amplifying signal 36 by 0.0679 units to obtain the correct pressure.

Referring to FIG. 10, a diagram of the digitized and linearized pressure sense amp signal 36, the linearized digital value of the temperature coefficient thermistor 16 and another embodiment of temperature according to the present utility model is shown; the difference between fig. 10 and fig. 8 is that the ptc thermistor 16 of fig. 10 is a ptc thermistor, so that the description of fig. 10 is omitted herein.

Referring to FIG. 11, a relationship between the digitized pressure sensing amplified signal 36 and the digital value of the temperature coefficient thermistor 16 is shown in another embodiment of the present utility model; the difference between fig. 11 and fig. 9 is that the ptc thermistor 16 of fig. 11 is a ptc thermistor, so that the details of fig. 11 are not repeated here. Wherein, the dotted line of fig. 11 has a temperature pressure equation: y= -0.0679x+2475.7.

While the above description of fig. 6-11 discusses digitized/linearized signals (e.g., digitized pressure sense amp signal 36, digitized and linearized digital value of the ic side temperature coefficient thermistor 16), the above description of fig. 6-11 is applicable to both the original pressure sense amp signal 36 and the ic side temperature coefficient thermistor 16, thereby achieving that the microcontroller 12 is configured to calibrate the pressure sense amp signal 36 using a temperature-pressure equation based on the ic side temperature. Furthermore, the relationship between the pressure sensing amplifying signal 36 and the pressure sensing signal 18 is merely an amplifying relationship, so the microcontroller 12 is configured to correct the content of the pressure sensing signal 18 by a temperature-pressure equation based on the integrated circuit temperature. Furthermore, the values of the equations and the values of the temperature and pressure equations are merely examples of the present utility model, and it should be understood that the values of the equations and the values of the temperature and pressure equations may be different under different conditions, parameters, applications and designs.

Furthermore, referring to fig. 2 and 5 again, the medium to be measured in the pipeline 40 may be referred to as a first layer, and has a first temperature; the membrane 34 may be referred to as a second layer having a second temperature; the lower oil chamber 32 may be referred to as a third layer, having a third temperature; upper oil gallery 38 may be referred to as a fourth layer having a fourth temperature. The auxiliary temperature coefficient thermistor 20 (disposed at the second location 44) can sense a first temperature, and the integrated circuit side temperature coefficient thermistor 16 (disposed at the first location 42) can sense a fourth temperature. Because of the dielectric thermal conductivity effects between the first, second, third and fourth layers, the following equations can be obtained: fourth temperature = first temperature-k2-second temperature-k3-third temperature, where K2 and K3 may be structural weighting coefficients, but the utility model is not limited to constants. The present utility model can also use the temperature of the measured medium in the pipeline 40, the temperature difference of the diaphragm 34, the temperature difference of the oil filling medium (the upper oil chamber 38 and the lower oil chamber 32 are filled with oil to be used as the medium for pressure sensing), and the temperature of the mems pressure sensing integrated circuit 14 to compensate and correct the sensed pressure value so as to improve the accuracy of pressure sensing.

The present utility model has the effect of improving the accuracy when using the MEMS pressure sensing integrated circuit 14 to sense pressure. Furthermore, the utility model detects temperature by adopting a low-cost negative temperature coefficient thermistor or a positive temperature coefficient thermistor instead of a high-specification thermosensitive element or a temperature detector, so that the utility model can avoid the high cost of the high-specification thermosensitive element or the temperature detector. The improved pressure sensing device 1 is configured to use a sum of temperature differences of the integrated circuit end temperature coefficient thermistor 16 and the auxiliary temperature coefficient thermistor 20 in combination with a weighting coefficient operation of the upper oil chamber 38, the lower oil chamber 32 and the diaphragm 34 as a temperature compensation mechanism.

However, the above description is only of the preferred embodiments of the present utility model, and the scope of the utility model is not limited to the above-mentioned embodiments, but is intended to be protected by the following claims. The present utility model is capable of other and further embodiments and its several details are capable of modification and variation in light of the present utility model, as will be apparent to those skilled in the art, without departing from the spirit and scope of the utility model as defined in the appended claims. In summary, the present utility model has industrial applicability, novelty and progress, and the structure of the present utility model is not found in the similar products and is disclosed, which completely accords with the requirements of the new patent application, and the present utility model is filed according to the patent laws.

Claims (7)

1. An improved pressure sensing device, comprising:

a microcontroller;

a micro-electromechanical system pressure sensing integrated circuit electrically connected to the microcontroller; a kind of electronic device with high-pressure air-conditioning system

An integrated circuit end temperature coefficient thermistor electrically connected to the microcontroller,

wherein the microcontroller is configured to detect an integrated circuit side temperature of the MEMS pressure sensing integrated circuit via the integrated circuit side temperature coefficient thermistor; the MEMS pressure sensing integrated circuit is configured to transmit a pressure sensing signal to the microcontroller; the microcontroller is configured to correct the pressure sensing signal using a temperature pressure equation based on the integrated circuit side temperature.

2. The improved pressure sensing device of claim 1, wherein the integrated circuit temperature coefficient thermistor is a negative temperature coefficient thermistor or a positive temperature coefficient thermistor, or a combination of a negative temperature coefficient thermistor and a positive temperature coefficient thermistor.

3. The improved pressure sensing device of claim 1, further comprising:

and the operational amplifier is electrically connected to the microcontroller and the micro-electromechanical system pressure sensing integrated circuit.

4. The improved pressure sensing device of claim 1, further comprising:

and the key set is electrically connected to the microcontroller.

5. The improved pressure sensing device of claim 1, further comprising:

and the light-emitting diode display is electrically connected to the microcontroller.

6. The improved pressure sensing device of claim 1, further comprising:

and the output interface is electrically connected to the microcontroller.

7. The improved pressure sensing device of claim 2, further comprising:

the micro-electromechanical system pressure sensing integrated circuit and the integrated circuit end temperature coefficient thermistor are arranged on the upper oil cavity;

a lower oil chamber connected to the upper oil chamber;

the diaphragm is arranged in the lower oil cavity; a kind of electronic device with high-pressure air-conditioning system

An auxiliary temperature coefficient thermistor arranged on the lower oil cavity,

the improved pressure sensing device is configured to use a temperature difference sum of the integrated circuit end temperature coefficient thermistor and the auxiliary temperature coefficient thermistor to be combined with a weighting coefficient operation of the upper oil cavity, the lower oil cavity and the diaphragm to serve as a temperature compensation mechanism.