CN114136527A

CN114136527A - Sensing element and vehicle

Info

Publication number: CN114136527A
Application number: CN202111457207.8A
Authority: CN
Inventors: 孙铁钢; 王丰; 梁宇询; 魏庆山; 何燕君; 张大伟; 王雅南; 郝学信; 秦奋; 赵福成; 王瑞平; 肖逸阁
Original assignee: Zhejiang Geely Holding Group Co Ltd; Ningbo Geely Royal Engine Components Co Ltd; Aurora Bay Technology Co Ltd
Current assignee: Zhejiang Geely Holding Group Co Ltd; Ningbo Geely Royal Engine Components Co Ltd; Aurora Bay Technology Co Ltd
Priority date: 2021-11-29
Filing date: 2021-11-29
Publication date: 2022-03-04

Abstract

The invention discloses a sensitive element and a vehicle, wherein the sensitive element comprises: the stress cup comprises a cylindrical side wall with openings at two ends and a cup bottom wall with an opening at one end for sealing the cylindrical side wall, the cylindrical side wall and the cup bottom wall jointly limit a stress cavity, the cylindrical side wall, the cup bottom wall and the stress cavity are all provided with first axes, one side, close to the stress cavity, of the cup bottom wall is provided with a stress surface serving as the cavity bottom of the stress cavity, one side, far away from the stress cavity, of the cup bottom wall is provided with a resistor mounting surface, the radius of the resistor mounting surface is larger than that of the stress surface, and the resistor mounting surface comprises a first mounting area corresponding to the stress surface and a second mounting area annularly arranged in the first mounting area; the piezoresistor comprises a first resistor, a second resistor, a third resistor and a fourth resistor, the second resistor and the third resistor are arranged in a first installation area, and the first resistor and the fourth resistor are arranged in a second installation area. The technical scheme of the invention aims to reduce the nonlinear error existing in the acquisition signal of the sensitive element.

Description

Sensing element and vehicle

Technical Field

The invention relates to the technical field of vehicles, in particular to a sensitive element and a vehicle.

Background

The Pressure Transducer is a device or apparatus capable of sensing a Pressure signal and converting the Pressure signal into a usable output electrical signal according to a certain rule, wherein a sensing element is an important component of the Pressure Transducer, and a non-linear error exists in a signal acquired by the sensing element, which greatly affects the accuracy of measurement of the Pressure Transducer.

Disclosure of Invention

The main object of the present invention is to provide a sensor intended to reduce the non-linear errors present in the acquisition signal of the sensor.

In order to achieve the above object, the present invention provides a sensor comprising:

the stress cup comprises a cylindrical side wall with openings at two ends and a cup bottom wall with an opening at one end for sealing the cylindrical side wall, the cylindrical side wall and the cup bottom wall jointly limit a stress cavity, the cylindrical side wall, the cup bottom wall and the stress cavity are all provided with a first axis, one side of the cup bottom wall close to the stress cavity is provided with a stress surface which is the cavity bottom of the stress cavity, one side far away from the stress cavity is provided with a resistor installation surface, the radius of the resistor installation surface is larger than that of the stress surface, and the resistor installation surface comprises a first installation area corresponding to the stress surface and a second installation area annularly arranged in the first installation area; and

the piezoresistor comprises a first resistor, a second resistor, a third resistor and a fourth resistor, wherein the second resistor and the third resistor are arranged in a first installation area, and the first resistor and the fourth resistor are arranged in a second installation area.

Optionally, the first resistor, the second resistor, the third resistor, and the fourth resistor are sequentially disposed on a first straight line, and the first straight line intersects with the first axis.

Optionally, the first straight line has a first position where a is a strain amount, a second position where b is a strain amount, a third position where c is a strain amount, and a fourth position where d is a strain amount, where an absolute value of a is equal to an absolute value of b, an absolute value of c is equal to an absolute value of d, the first resistor is disposed in the first position, the second resistor is disposed in the second position, the third resistor is disposed in the third position, and the fourth resistor is disposed in the fourth position.

Optionally, the sensing element further includes a stress island disposed on the stress surface, and the first axis passes through the stress island.

Optionally, the stress island has a thickness greater than or equal to 0.5 times the thickness of the cup bottom wall.

Optionally, the stress cup is provided with a rounded corner at the periphery of the stress surface.

Optionally, the radius of the rounded corner has a value less than the thickness of the cup bottom wall.

Optionally, the cylindrical side wall is provided with a connection structure for connecting with an external element at a position far away from the cup bottom wall.

Optionally, an annular groove is formed in the outer peripheral surface of the cylindrical side wall between the connecting structure and the cup bottom wall, the annular groove surrounds the first axis, and the distance from the first axis to the bottom of the annular groove is smaller than or equal to the distance from the first axis to the periphery of the resistor mounting surface.

The invention also provides a vehicle which comprises the sensitive element.

In the technical scheme of the invention, two opposite sides of the cup bottom wall are respectively a stress surface and a resistor mounting surface, when gas or oil in a stress cavity presses the stress surface, corresponding strain quantities can be generated at corresponding positions of the resistor mounting surface, wherein the strain quantity of a first mounting region is a positive value, the strain quantity of a second mounting region is a negative value, collected signals of a second resistor and a third resistor which are installed in the first mounting region are positive strain quantities, and collected signals of a first resistor and a fourth resistor which are installed in the second mounting region are negative strain quantities, it is required to be noted that the first resistor, the second resistor, the third resistor and the fourth resistor are electrically connected by the principle of a Wheatstone bridge, and it can be understood that the arrangement mode of the piezoresistors on the resistor mounting surface is favorable for enabling nonlinear errors DeltaR 1/R1+ R2/R2 and DeltaR 3/R3 +. DeltaR 4/R4 to be close to zero, that is, the non-linear error existing in the acquired signal of the sensor is reduced, and it should be noted that the first resistor corresponds to R1, the second resistor corresponds to R2, and the third resistor corresponds to R3 and the fourth resistor corresponds to R4.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the structures shown in the drawings without creative efforts.

FIG. 1 is a cross-sectional view of one embodiment of a sensor of the present invention;

FIG. 2 is a layout view of the piezoresistors on the resistor mounting surface;

fig. 3 is a strain diagram of the sensor in the first line of fig. 2.

The reference numbers illustrate:

reference numerals	Name (R)	Reference numerals	Name (R)
				100	Stress cup	335	Center point
110	Fillet	350	Stress island
				200	Cylindrical side wall	400	Voltage dependent resistor
210	Ring groove	410	A first resistor
				230	Connection structure	420	Second resistance
250	First connecting section	430	Third resistance
				270	Second connecting section	440	Fourth resistor
271	Mounting surface	500	Stress cavity
				300	Cup bottom wall	510	First stress cavity
310	Stress surface	530	Second stress cavity
				330	Resistor mounting surface	600	First axis
331	First mounting region	700	A first straight line
				333	Second mounting area

The implementation, functional features and advantages of the objects of the present invention will be further explained with reference to the accompanying drawings.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

It should be noted that all the directional indicators (such as up, down, left, right, front, and rear … …) in the embodiment of the present invention are only used to explain the relative position relationship between the components, the motion situation, and the like in a specific posture, and if the specific posture is changed, the directional indicator is changed accordingly.

In the present invention, unless otherwise expressly stated or limited, the terms "connected," "secured," and the like are to be construed broadly, and for example, "secured" may be a fixed connection, a removable connection, or an integral part; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or they may be connected internally or in any other suitable relationship, unless expressly stated otherwise. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

In addition, if there is a description of "first", "second", etc. in an embodiment of the present invention, the description of "first", "second", etc. is for descriptive purposes only and is not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In addition, the meaning of "and/or" appearing throughout includes three juxtapositions, exemplified by "A and/or B" including either A or B or both A and B. In addition, technical solutions between various embodiments may be combined with each other, but must be realized by a person skilled in the art, and when the technical solutions are contradictory or cannot be realized, such a combination should not be considered to exist, and is not within the protection scope of the present invention.

The invention provides a sensitive element.

Referring to fig. 1 and 2, in one embodiment of the present invention, the sensing element includes:

the stress cup 100 comprises a cylindrical side wall 200 with two open ends and a cup bottom wall 300 for sealing one open end of the cylindrical side wall 200, the cylindrical side wall 200 and the cup bottom wall 300 jointly limit a stress cavity 500, the cylindrical side wall 200, the cup bottom wall 300 and the stress cavity 500 all have a first axis 600, one side of the cup bottom wall 300 close to the stress cavity 500 is provided with a stress surface 310 which is the cavity bottom of the stress cavity 500, one side far away from the stress cavity 500 is provided with a resistor mounting surface 330, the radius of the resistor mounting surface 330 is larger than that of the stress surface 310, and the resistor mounting surface 330 comprises a first mounting area 331 corresponding to the stress surface 310 and a second mounting area 333 which is annularly arranged in the first mounting area 331; and

the varistor 400 includes a first resistor 410, a second resistor 420, a third resistor 430, and a fourth resistor 440, where the second resistor 420 and the third resistor 430 are disposed in the first mounting region 331, and the first resistor 410 and the fourth resistor 440 are disposed in the second mounting region 333.

In the technical solution of the present invention, the two opposite sides of the cup bottom wall 300 are respectively a stress surface 310 and a resistor mounting surface 330, when gas or oil in the stress cavity 500 presses the stress surface 310, a corresponding strain amount is generated at a corresponding position of the resistor mounting surface 330, where the strain amount of the first mounting region 331 is a positive value, and the strain amount of the second mounting region 333 is a negative value, then the collected signals of the second resistor 420 and the third resistor 430 mounted in the first mounting region 331 are positive strain amounts, and the collected signals of the first resistor 410 and the fourth resistor 440 mounted in the second mounting region 333 are negative strain amounts, it should be noted that the first resistor 410, the second resistor 420, the third resistor 430 and the fourth resistor 440 are electrically connected by a wheatstone bridge principle, it can be understood that the arrangement manner of the resistor 400 on the resistor mounting surface 330 is favorable for making nonlinear errors Δ R1/R1+ R2/R2 and Δ R3/R4/3/4 + approach to zero, that is, the non-linear error existing in the acquired signal of the sensor is reduced, and it should be noted that the first resistor 410 corresponds to R1, the second resistor 420 corresponds to R2, and the third resistor 430 corresponds to R3, and the fourth resistor 440 corresponds to R4.

Optionally, in an embodiment, the first resistor 410, the second resistor 420, the third resistor 430, and the fourth resistor 440 are sequentially disposed on a first straight line 700, the first straight line 700 intersects the first axis 600, the intersection of the first straight line 700 and the first axis 600 is beneficial to positioning the first straight line 700, and the first resistor 410, the second resistor 420, the third resistor 430, and the fourth resistor 440 are sequentially disposed along the first straight line 700, so that the layout of the piezoresistor 400 is facilitated.

Optionally, referring to fig. 3 together, in an embodiment, the first straight line 700 has a first position with a strain amount a, a second position with b strain amount, a third position with c strain amount, and a fourth position with d strain amount, wherein an absolute value of a is equal to an absolute value of b, an absolute value of c is equal to an absolute value of d, the first resistor 410 is disposed at the first position, the second resistor 420 is disposed at the second position, the third resistor 430 is disposed at the third position, and the fourth resistor 440 is disposed at the fourth position, such that non-linearity errors Δ R1/R1 +/Δ R2/R2 and Δ R3/R3 +/Δ R4/R4 are all equal to zero.

For better illustration, the intersection of the first axis 600 and the resistor mounting surface 330 is defined as a center point 335, when the stress chamber 500 is filled with gas or liquid, the strain on the resistor mounting surface 330 gradually decreases from the center point 335 to the outside, and the strain at the boundary between the first mounting region 331 and the second mounting region 333 is zero, it can be understood that, in an ideal state, a circle with the center point 335 as a center point has equal strain at any point of the circle, so in other embodiments, for the first resistor 410, as long as any point is selected on the circle with the center point 335 as a center point and the distance from the first position to the center point 335 as a radius, the second resistor 420, the third resistor 430 and the fourth resistor 440 are the same, and details are not repeated herein.

Specifically, in one embodiment, the absolute values of the amount of strain a, the amount of strain b, the amount of strain c, and the amount of strain d are relative, and thus, the first position, the second position, the third position, and the fourth position are easily determined.

It should be noted that fig. 3 is a strain graph on the sensing element, and the abscissa represents the position on the first straight line 700 and the ordinate represents the strain amount, wherein the position with the abscissa of 0 is the position of the center point 335.

It is worth mentioning that if the wall thickness of the cup bottom wall 300 is neglected, the projection of the stress surface 310 coincides with the projection of the first mounting area 331 in the first direction. Of course, it will be appreciated that in actual production the cup bottom wall 300 is thin and the area of the stress surface 310 can be considered to be equal to the area of the first mounting area 331.

Optionally, in an embodiment, the sensing element further includes a stress island 350 disposed on the stress surface 310, and the first axis 600 passes through the stress island 350, it can be understood that the stress island 350 is in an island shape and protrudes from the stress surface 310; when the stress cavity 500 is filled with gas or liquid, the penetrating position of the cup bottom wall 300 on the first axis 600 is a place with a large strain amount, if the position is in a state with a large strain amount for a long time, the cup bottom wall 300 is easy to creep and even crack, the position is defined as a creep position, the strain distribution of the cup bottom wall 300 can be improved by arranging the stress island 350, the stress island 350 phase changes to increase the thickness of the creep position of the cup bottom wall 300, the structural strength of the cup bottom wall 300 at the creep position is improved, the creep of the cup bottom wall 300 is favorably inhibited, and the measurement accuracy of the sensitive element is improved. As shown in fig. 3, under the action of the stress island 350, the strain curve near the position with the abscissa of 0 is concave, so that the positive and negative symmetry of the strain curve is improved.

Optionally, in an embodiment, the thickness of the stress island 350 is greater than or equal to 0.5 times the thickness of the cup bottom wall 300. The thicker the stress islands 350, the better the effect of suppressing creep deformation of the cup bottom wall 300, and when the thickness of the stress islands 350 is greater than or equal to 0.5 times the thickness of the cup bottom wall 300, the effect of the stress islands 350 in suppressing creep deformation of the cup bottom wall 300 is more significant. It is understood that the total thickness of the stress island 350 plus the cup bottom wall 300 is greater than or equal to 1.5 times the thickness of the cup bottom wall 300.

Optionally, in an embodiment, the stress cup 100 is provided with a rounded corner 110 at the periphery of the stress surface 310, and when the stress cavity 500 is filled with gas or liquid, the rounded corner 110 is beneficial to avoid stress concentration at the stress surface, inhibit creep at the stress surface, avoid structural damage of sensitive elements under high pressure, and improve stress distribution at the positions of the first resistor 410 and the fourth resistor 440.

Further, in an embodiment, the radius value of the rounded corner 110 is smaller than the thickness value of the cup bottom wall 300, and it can be understood that the radius value of the rounded corner 110 cannot be too large, which easily causes the stress value on the resistor mounting surface 330 to be small, which may affect the measurement of the varistor 400, and further affect the sensitivity of the sensing element, so that when the radius value of the rounded corner 110 is smaller than the thickness value of the cup bottom wall 300, the sensing element may not only inhibit the generation of creep, but also have higher sensitivity. It will be appreciated that providing the rounded corners 110 may also improve the lifetime of the sensing elements.

Alternatively, in an embodiment, the ratio of the radius value of the rounded corner 110 to the thickness value of the cup bottom wall 300 is less than 1 and greater than or equal to 0.8, when the ratio is small, a large stress is generated at the periphery of the stress surface 310, which is easy to cause creep deformation of the cup bottom wall 300, and when the ratio is large, although the stress is small, the measurement of the piezoresistor 400 is affected, and thus the sensitivity of the sensor is affected. Therefore, when the ratio is less than 1 and 0.8 or more, creep of the cup bottom wall 300 can be suppressed and high sensitivity of the sensor can be ensured.

Optionally, in an embodiment, the cylindrical sidewall 200 is provided with a connection structure 230 for connecting with an external element at a position far away from the cup bottom wall 300, so that the interaction force between the external element and the connection structure 230 has a far distance to the cup bottom wall 300, thereby having a weak influence on the cup bottom wall 300, that is, the measurement of the piezoresistor 400 on the resistor mounting surface 330 is weak, which is beneficial to improving the measurement accuracy of the sensitive element.

Specifically, in an embodiment, the cylindrical sidewall 200 includes a first connecting section 250 connected to the cup bottom wall 300, and a second connecting section 270 connected to the first connecting section 250, wherein a radius of the second connecting section 270 is larger than a radius of the first connecting section 250, the second connecting section 270 is a connecting structure 230, a mounting surface 271 surrounding the first connecting section 250 and exposed outside is disposed on a side of the second connecting section 270 close to the first connecting section 250, and the mounting surface 271 is used for mounting and connecting an external element. However, the design is not limited thereto, and in other embodiments, the connection structure 230 is an additional structure, and the connection structure 230 is protruded on the outer circumferential surface of the cylindrical sidewall 200 for connecting with an external element.

Optionally, in an embodiment, an annular groove 210 is provided on the outer peripheral surface of the cylindrical sidewall 200 between the connecting structure 230 and the cup bottom wall 300, the annular groove 210 surrounds the first axis 600, and a distance from the first axis 600 to a bottom of the annular groove 210 is smaller than or equal to a distance from the first axis 600 to the periphery of the resistor mounting surface 330, so as to facilitate blocking a force applied to the connecting structure 230 by an external element from being transmitted to the cup bottom wall 300, so as to ensure the measurement accuracy of the thermistor, and thus ensure the measurement accuracy of the thermistor.

Alternatively, in an embodiment, in the extending direction of the first axis 600, the stress cavity 500 includes a first stress cavity 510 and a second stress cavity 530 which are communicated with each other, the first stress cavity 510 is disposed near the cup bottom wall 300, and the inner diameter of the second stress cavity 530 is larger than that of the first stress cavity 510, it can be understood that the stress cavity 500 has a certain depth, it is difficult to process the stress cavity 500 at one time, and the stress cavity 500 can be easily formed by dividing the stress cavity 500 into the first stress cavity 510 and the second stress cavity 530 for separate processing.

The invention further provides a vehicle, which includes the above-mentioned sensing element, and the specific structure of the sensing element refers to the above-mentioned embodiments, and since the vehicle adopts all the technical solutions of all the above-mentioned embodiments, the vehicle at least has all the beneficial effects brought by the technical solutions of the above-mentioned embodiments, and details are not repeated herein.

The above description is only an alternative embodiment of the present invention, and not intended to limit the scope of the present invention, and all modifications and equivalents of the present invention, which are made by the contents of the present specification and the accompanying drawings, or directly/indirectly applied to other related technical fields, are included in the scope of the present invention.

Claims

1. A sensor, comprising:

2. The sensor of claim 1, wherein the first resistor, the second resistor, the third resistor, and the fourth resistor are arranged in sequence on a first line, the first line intersecting the first axis.

3. The sensor of claim 2, wherein the first line has a first position having an amount of strain a, a second position having an amount of strain b, a third position having an amount of strain c, and a fourth position having an amount of strain d, wherein the absolute value of a is equal to the absolute value of b, the absolute value of c is equal to the absolute value of d, the first resistor is disposed at the first position, the second resistor is disposed at the second position, the third resistor is disposed at the third position, and the fourth resistor is disposed at the fourth position.

4. The sensing element of claim 1, further comprising a stress island disposed on the stress surface, the first axis passing through the stress island.

5. The sensor of claim 4, wherein the stress island has a thickness greater than or equal to 0.5 times the thickness of the cup bottom wall.

6. The sensor of claim 1 wherein the stress cup is rounded at a periphery of the stress surface.

7. The sensor of claim 6 wherein the radius of the fillet has a value less than a value of a thickness of the cup bottom wall.

8. The sensor of any one of claims 1 to 7 wherein the cylindrical sidewall is provided with a connection structure for connection to an external element at a location remote from the cup bottom wall.

9. The sensor of claim 8 wherein the outer peripheral surface of the cylindrical sidewall has an annular groove between the attachment structure and the cup bottom wall, the annular groove surrounding the first axis, the distance from the first axis to the bottom of the annular groove being less than or equal to the distance from the first axis to the periphery of the resistive mounting surface.

10. A vehicle, characterized in that it comprises a sensor according to any one of claims 1 to 9.