CN118089990A - Capacitive detection structure and electronic equipment - Google Patents
Capacitive detection structure and electronic equipment Download PDFInfo
- Publication number
- CN118089990A CN118089990A CN202410215747.2A CN202410215747A CN118089990A CN 118089990 A CN118089990 A CN 118089990A CN 202410215747 A CN202410215747 A CN 202410215747A CN 118089990 A CN118089990 A CN 118089990A
- Authority
- CN
- China
- Prior art keywords
- cantilever beam
- circuit board
- plate
- base
- cover plate
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000001514 detection method Methods 0.000 title abstract description 59
- 229910001220 stainless steel Inorganic materials 0.000 claims description 5
- 239000010935 stainless steel Substances 0.000 claims description 5
- 238000005452 bending Methods 0.000 claims description 3
- 125000006850 spacer group Chemical group 0.000 claims description 3
- 230000035945 sensitivity Effects 0.000 abstract description 18
- 230000008859 change Effects 0.000 description 15
- 238000006073 displacement reaction Methods 0.000 description 14
- 238000004364 calculation method Methods 0.000 description 7
- 238000000034 method Methods 0.000 description 7
- 230000008569 process Effects 0.000 description 7
- 238000010586 diagram Methods 0.000 description 6
- 230000009471 action Effects 0.000 description 5
- 238000004519 manufacturing process Methods 0.000 description 4
- 239000000463 material Substances 0.000 description 4
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 3
- 230000006835 compression Effects 0.000 description 3
- 238000007906 compression Methods 0.000 description 3
- 229910052802 copper Inorganic materials 0.000 description 3
- 239000010949 copper Substances 0.000 description 3
- 230000009286 beneficial effect Effects 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 230000002035 prolonged effect Effects 0.000 description 2
- 238000000926 separation method Methods 0.000 description 2
- 229910052782 aluminium Inorganic materials 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 239000003990 capacitor Substances 0.000 description 1
- 230000005684 electric field Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000006260 foam Substances 0.000 description 1
- 230000003993 interaction Effects 0.000 description 1
- 238000003825 pressing Methods 0.000 description 1
- 230000008093 supporting effect Effects 0.000 description 1
Landscapes
- Measuring Fluid Pressure (AREA)
Abstract
The embodiment of the disclosure provides a capacitive detection structure and an electronic device, comprising: the device comprises a base and a cover plate positioned right above the base, wherein the base is spaced from the cover plate, and the cover plate is used for bearing pressure; the circuit board is positioned on one surface of the cover plate facing the base; the first cantilever beam and the second cantilever beam are respectively and fixedly connected to two opposite ends of one surface of the circuit board, which is far away from the cover plate; the length of the first cantilever beam along the direction parallel to the surface of the circuit board is longer than the length of the second cantilever beam along the direction parallel to the surface of the circuit board; the first pole plate is fixedly connected to one surface of the first cantilever beam, which faces the base, and the second pole plate is positioned on one surface of the base, which faces the circuit board. The embodiment of the disclosure improves the sensitivity of capacitance detection by extending one cantilever beam and utilizing the lever principle.
Description
Technical Field
The embodiment of the disclosure relates to the technical field of pressure testing, in particular to a capacitive detection structure and electronic equipment.
Background
A touch panel is a type of touch sensing input device that is now widely used. In the field of touch pads, consumers have not been satisfied with simple touch operations, and the demand for pressure detection is also increasing. Many pressure detection schemes, such as a capacitance scheme, an inductance scheme, a strain gauge scheme, a pressure film scheme, and the like, are currently emerging. The capacitance detection scheme is widely applied due to the characteristics of low cost, high precision, high reliability and the like.
In a conventional capacitance detection scheme, the pressure applied to the touch panel is calculated by detecting the change of the capacitance value between two polar plates, wherein one polar plate is positioned at the bottom of the panel of the touch panel, the other polar plate is positioned on a fixed base opposite to the touch panel, a gap is reserved between the two polar plates, when the surface of the panel of the touch panel is pressed, downward tiny displacement is generated, the vertical interval distance between the two polar plates is changed, the capacitance value between the polar plates is changed, and the pressure applied to the touch panel can be calculated according to the capacitance change value and the change of the detected capacitance value.
However, since the capacitance detecting structure is usually disposed inside the device, the displacement variation of the plate at the bottom of the touch panel cannot be too large when pressure is applied due to the limitation of the internal space of the device, so that the vertical interval distance between the two plates is also small, thereby possibly affecting the sensitivity of detection.
Disclosure of Invention
The embodiment of the disclosure provides a capacitive detection structure and electronic equipment, which are at least beneficial to solving the problem of low detection sensitivity of the capacitive detection structure.
According to some embodiments of the present disclosure, an aspect of an embodiment of the present disclosure provides a capacitive detection structure, including: the device comprises a base and a cover plate positioned right above the base, wherein the base is spaced from the cover plate, and the cover plate is used for bearing pressure; the circuit board is positioned on one surface of the cover plate, which faces the base; the first cantilever beam and the second cantilever beam are respectively and fixedly connected to two opposite ends of one surface of the circuit board, which is far away from the cover plate; the length of the first cantilever beam along the direction parallel to the surface of the circuit board is longer than the length of the second cantilever beam along the direction parallel to the surface of the circuit board; the circuit board comprises a base, a first cantilever beam, a second cantilever beam, a first polar plate and a second polar plate, wherein a right-facing area is arranged between the first polar plate and the second polar plate, the first polar plate is fixedly connected to one surface of the first cantilever beam, which faces the base, and the second polar plate is positioned on one surface of the base, which faces the circuit board.
In some embodiments, one end of the circuit board is fixedly connected to the outer side wall of the first cantilever beam and the second cantilever beam Liang Yuanli, and as the cover plate is pressed, the first cantilever beam and the second cantilever beam are bent and deformed, and the first cantilever beam drives the first polar plate to move towards the second polar plate.
In some embodiments, the first cantilever beam comprises: the circuit board comprises a fixed end and an extension end, wherein one end of the fixed end is fixedly connected with the outer side wall, one end of the extension end, which is far away from the outer side wall, is fixedly connected with the fixed end, and the extension end extends along a direction parallel to the surface of the circuit board.
In some embodiments, the length of the second cantilever beam in a direction parallel to the circuit board surface is equal to the length of the fixed end in a direction parallel to the circuit board surface.
In some embodiments, further comprising: the two gaskets are respectively arranged between the first cantilever beam and the circuit board and between the second cantilever beam and the circuit board.
In some embodiments, the thickness of the shim is 0.3mm to 2mm.
In some embodiments, the first and second cantilever beams have a thickness of 0.01mm to 1mm.
In some embodiments, the first cantilever beam and the second cantilever beam are each made of stainless steel.
In some embodiments, further comprising: the shielding layer is arranged in the circuit board; wherein, the cross-sectional area of shielding layer is the same as the cross-sectional area of circuit board.
According to some embodiments of the present disclosure, another aspect of embodiments of the present disclosure further provides an electronic device, including: the capacitive detection structure of any one of the above embodiments; and the processor is configured to acquire the capacitance value variation when the cover plate is subjected to pressure and detect the pressure applied to the cover plate based on the capacitance value variation.
The technical scheme provided by the embodiment of the disclosure has at least the following advantages:
In the technical scheme of the capacitive detection structure provided by the embodiment of the disclosure, a base and a cover plate positioned right above the base are arranged at intervals, and the cover plate is used for bearing pressure; the circuit board is positioned on one surface of the cover plate, which faces the base; the first cantilever beam and the second cantilever beam are respectively and fixedly connected to two opposite ends of one surface of the circuit board, which is far away from the cover plate; the length of the first cantilever beam along the direction parallel to the surface of the circuit board is longer than the length of the second cantilever beam along the direction parallel to the surface of the circuit board; the circuit board comprises a base, a first cantilever beam, a second cantilever beam, a first polar plate and a second polar plate, wherein a right-facing area is arranged between the first polar plate and the second polar plate, the first polar plate is fixedly connected to one surface of the first cantilever beam, which faces the base, and the second polar plate is positioned on one surface of the base, which faces the circuit board. According to the embodiment of the disclosure, the cantilever beam is prolonged, the lever principle is utilized, and therefore in the process that the cover plate receives pressure, the downward moving distance of the first polar plate arranged on one face of the first cantilever beam, which faces the base, is larger than the downward moving distance of the cover plate, according to the calculation formula of the capacitance, the capacitance variation between the two polar plates is increased compared with that of the first polar plate arranged on one face of the cover plate, which faces the base, and then the pressure received by the cover plate is calculated according to the calculation formula of the pressure, so that the sensitivity of capacitance detection can be improved.
Drawings
One or more embodiments are illustrated by way of example and not limitation in the figures of the accompanying drawings, which are not to be construed as limiting the embodiments unless specifically indicated otherwise; in order to more clearly illustrate the embodiments of the present disclosure or the technical solutions in the conventional technology, the drawings required for the embodiments will be briefly described below, and it is apparent that the drawings in the following description are only some embodiments of the present disclosure, and other drawings may be obtained according to these drawings without inventive effort to those of ordinary skill in the art.
FIG. 1 is a capacitive sensing structure;
FIG. 2 is a schematic structural diagram of the capacitive sensing structure of the cover plate of FIG. 1 when being pressed;
FIG. 3 is a graph showing the change in distance between plates when the cover plate of FIG. 1 is subjected to pressure;
FIG. 4 is a schematic diagram of a capacitive sensing structure according to an embodiment of the disclosure;
FIG. 5 is a schematic structural diagram of the capacitive sensing structure of FIG. 4 when the cover is under pressure;
FIG. 6 is a graph showing the change in distance between plates when the cover plate of FIG. 4 is subjected to pressure;
FIG. 7 is a schematic illustration of a variation of the first cantilever beam when the cover is under pressure.
Detailed Description
As known from the background art, the existing capacitive detection structure has the problem of low detection sensitivity.
Fig. 1 is a capacitive sensing structure. Fig. 2 is a schematic structural diagram of the capacitive sensing structure of the cover 103 in fig. 1 when being pressed. Referring to fig. 1 and 2 in combination, analysis has found that one of the reasons for the low detection sensitivity of the capacitive detection structure is: since the capacitance detecting structure is usually disposed inside the device, but the space inside the device is usually small, the displacement of the plate at the bottom of the cover 103 will not be too large when the cover 103 is pressed, and thus the vertical separation distance between the two plates will be small. Specifically, the first cantilever beam 106 and the second cantilever beam 107 are fixedly connected with the outer side wall respectively, the first cantilever beam 106 and the second cantilever beam 107 are elastic, the two polar plates comprise a first polar plate 104 and a second polar plate 105, the base 101 and the cover plate 103 are arranged at intervals, the first polar plate 104 is positioned on one surface of the cover plate 103 facing the base 101, the second polar plate 105 is positioned on one surface of the base 101 facing the circuit board 102, when the cover plate 103 is stressed, the cover plate 103 and the circuit board 102 move towards the second polar plate 105 under the action of stress, the first cantilever beam 106 and the second cantilever beam 107 are bent and deformed, the first polar plate 104 is driven by the cover plate 103 and the circuit board 102 to move towards the second polar plate 105, and the capacitance value between the first polar plate 104 and the second polar plate 105 changes, but in order to enable the whole device to be lighter and portable, the arrangement space inside the device is usually smaller, when the polar plate is not stressed, the spacing between the first polar plate 104 and the second polar plate 105 is smaller when the polar plate is stressed, the capacitance value between the first polar plate 104 and the second polar plate 105 is stressed, the capacitance value is smaller, the capacitance value is also smaller, the capacitance value between the first polar plate 104 and the second polar plate 105 is stressed, the capacitance value is smaller, the sensitivity is smaller, the capacitance value is smaller and the sensitivity is smaller, and the capacitance value is smaller.
Fig. 3 is a graph showing the distance between the plates when the cover 103 is pressed in fig. 1.
Referring to fig. 1,2 and 3 in combination, when the cover plate 103 is pressed, the distance between the first electrode plate 104 and the second electrode plate 105 becomes smaller. When the cover plate 103 is not under pressure, the capacitance between the first polar plate 104 and the second polar plate 105 is calculated as:
C 1 =εS/d 1
Where ε is the dielectric permittivity, S is the area of the first plate 104, and d is the vertical distance between the first plate 104 and the second plate 105.
When the cover plate 103 is pressed, the distance between the first polar plate 104 and the second polar plate 105 becomes smaller, and at this time, the capacitance calculation formula between the first polar plate 104 and the second polar plate 105 is as follows:
C 2＝εS/d1 type 2
Where ε is the dielectric constant, S is the area of the first polar plate 104, and d 1 is the vertical distance between the first polar plate 104 and the second polar plate 105 when the cover plate 103 is pressed.
Further, according to the mechanical calculation formula, the pressure applied to the cover 103 is:
F 1＝K(d-d1) type 3
Wherein K is the rigidity coefficient of the capacitive detection structure in the vertical direction.
As can be seen from equations 1,2 and 3, the amount of change in the vertical distance between the first electrode plate 104 and the second electrode plate 105 and the pressure applied to the cover plate 103 are calculated by detecting the amount of change in the capacitance between the first electrode plate 104 and the second electrode plate 105, and the pressure applied to the cover plate 103 is calculated.
Further, for the capacitive detection structure of fig. 1, the detection sensitivity is:
Sens 1＝(C2-C1)/F1 type 4
As can be seen from the combination of equations 1 to 4, since the difference between the vertical distance d between the first electrode plate 104 and the second electrode plate 105 when the cover 103 is not under pressure and the vertical distance d 1 between the first electrode plate 104 and the second electrode plate 105 when the cover 103 is under pressure is too small, i.e. the displacement of the first electrode plate 104 is too small, the difference between the capacitance C 1 between the first electrode plate 104 and the second electrode plate 105 when the cover 103 is not under pressure and the capacitance C 2 between the first electrode plate 104 and the second electrode plate 105 when the cover 103 is under pressure is too small, which results in too small detection sensitivity Sens 1 of the capacitive detection structure of fig. 1, and poor detection sensitivity of the capacitive detection structure of fig. 1.
The embodiment of the disclosure provides a capacitive detection structure and electronic equipment, which are at least beneficial to solving the problem of low detection sensitivity of the capacitive detection structure.
According to an embodiment of the present disclosure, a capacitive detection structure provided by an embodiment of the present disclosure includes: a base 201 and a cover plate 203 located right above the base 201, the base 201 is spaced from the cover plate 203, and the cover plate 203 is used for bearing pressure; the circuit board 202, the circuit board 202 locates at one side facing the base 201 of the cover 203; the first cantilever beam 206 and the second cantilever beam 207, the first cantilever beam 206 and the second cantilever beam 207 are respectively and fixedly connected to two opposite ends of one surface of the circuit board 202 away from the cover plate 203; the length of the first cantilever beam 206 in the direction parallel to the surface of the circuit board 202 is greater than the length of the second cantilever beam 207 in the direction parallel to the surface of the circuit board 202; the first polar plate 204 and the second polar plate 205 are provided with opposite areas, the first polar plate 204 is fixedly connected to one surface of the first cantilever beam 206 facing the base 201, and the second polar plate 205 is positioned on one surface of the base 201 facing the circuit board 202.
Embodiments of the present disclosure will be described in detail below with reference to the attached drawings. However, those of ordinary skill in the art will understand that in the various embodiments of the present disclosure, numerous technical details have been set forth in order to provide a better understanding of the present disclosure. The technical solutions claimed in the present disclosure can be implemented without these technical details and with various changes and modifications based on the following embodiments.
Fig. 4 is a schematic diagram of a capacitive detection structure according to an embodiment of the disclosure. Fig. 5 is a schematic structural diagram of the capacitive sensing structure of the cover 203 in fig. 4 when the cover is pressed.
Referring to fig. 4 to 5, a capacitive detection structure provided by an embodiment of the present disclosure includes: a base 201 and a cover plate 203 located right above the base 201, the base 201 is spaced from the cover plate 203, and the cover plate 203 is used for bearing pressure; the circuit board 202, the circuit board 202 locates at one side facing the base 201 of the cover 203; the first cantilever beam 206 and the second cantilever beam 207, the first cantilever beam 206 and the second cantilever beam 207 are respectively and fixedly connected to two opposite ends of one surface of the circuit board 202 away from the cover plate 203; the length of the first cantilever beam 206 in the direction parallel to the surface of the circuit board 202 is greater than the length of the second cantilever beam 207 in the direction parallel to the surface of the circuit board 202; the first polar plate 204 and the second polar plate 205 are provided with opposite areas, the first polar plate 204 is fixedly connected to one surface of the first cantilever beam 206 facing the base 201, and the second polar plate 205 is positioned on one surface of the base 201 facing the circuit board 202.
In some embodiments, the ends of the first cantilever beam 206 and the second cantilever beam 207, which are far away from the circuit board 202, are fixedly connected to the outer side wall, and as the cover board 203 is pressed, the first cantilever beam 206 and the second cantilever beam 207 are bent and deformed, and the first cantilever beam 206 drives the first polar plate 204 to move toward the second polar plate 205.
In particular, the outer side wall may be at a side wall of the housing interior of the device housing the capacitive detection structure. When the cover plate 203 is pressed, one end of the first cantilever beam 206 and one end of the second cantilever beam 207 are respectively and fixedly connected with the circuit board 202, and the other end of the first cantilever beam 206 away from the circuit board 202 and the other end of the second cantilever beam 207 away from the circuit board 202 are respectively and fixedly connected with the outer side wall. Since the first cantilever beam 206 and the second cantilever beam 207 are both elastic, and the first electrode plate 204 is disposed on one surface of the first cantilever beam 206 facing the base 201, when the cover 203 is pressed, the cover 203 and the circuit board 202 move toward the base 201 under the action of the pressure, the first cantilever beam 206 and the second cantilever beam 207 are both bent and deformed, and the first electrode plate 204 moves toward the second electrode plate 205 under the driving of the first cantilever beam 206. Meanwhile, since there is a facing area between the first plate 204 and the second plate 205, and the second plate 205 located at the base 201 facing the circuit board 202 is electrically connected to the circuit board 202 through the flexible circuit board 202 or a wire, a capacitance value can be generated between the first plate 204 and the second plate 205.
Fig. 6 is a graph showing the change in the distance between the plates when the cover 203 in fig. 4 is pressed.
Referring to fig. 4, 5 and 6 in combination, there is a facing area between the first plate 204 and the second plate 205, and when the cover plate 203 is pressed, the first plate 204 is driven to move toward the metal sheet, and the vertical distance between the first plate 204 and the second plate 205 is changed, so that the capacitance value between the first plate 204 and the second plate 205 is also changed. When the cover 203 is not under pressure, the capacitance between the first plate 204 and the second plate 205 is calculated as:
c 3＝εS/d2 type 5
Where ε is the dielectric constant, S is the area of the first plate 204, and d 2 is the vertical distance between the first plate 204 and the second plate 205 when the cover 203 is not under pressure.
When the cover 203 is pressed, the distance between the first electrode plate 204 and the second electrode plate 205 becomes smaller, and at this time, the capacitance between the first electrode plate 204 and the second electrode plate 205 is calculated as:
C 4＝εS/d3 type 6
Where ε is the dielectric constant, S is the area of the first plate 204, and d 3 is the vertical distance between the first plate 204 and the second plate 205 when the cover 203 is under pressure.
Further, according to the mechanical calculation formula, the pressure applied to the cover 203 is:
F 2＝K(d2-d3) type 7
Wherein K is the rigidity coefficient of the capacitive detection structure in the vertical direction.
As can be seen from equations 4,5 and 6, the amount of change in the vertical distance between the first plate 204 and the second plate 205 and thus the pressure applied to the cover 203 are calculated by detecting the amount of change in the capacitance between the first plate 204 and the second plate 205, and the pressure applied to the cover 203 is calculated.
Further, for the capacitive detection structure of fig. 4, the detection sensitivity is:
Sens 2＝(C4-C3)/F2 type 8
In some embodiments, the first cantilever beam 206 comprises: the fixed end 216 and the extension end, the one end fixed connection of fixed end 216 is in the lateral wall, the one end fixed connection that the extension end and fixed end 216 kept away from the lateral wall, and the extension end extends along the direction that is parallel to circuit board 202 surface.
As can be seen from fig. 5 to 8, the extension end 226 of the first cantilever beam 206 corresponds to a portion of the arm that increases the force applied to the first electrode plate 204, and the first cantilever beam 206 can drive the first electrode plate 204 to move towards the second electrode plate 205 by a larger displacement when the cover 203 is subjected to the same pressure. That is, the first plate 204 is disposed on a surface of the first cantilever beam 206 facing the second plate 205, and the displacement of the first plate 204 moving toward the second plate 205 is greater than the displacement of the cover 203 moving toward the second plate 205 during the process that the cover 203 is pressurized. It can be understood that, when the cover 203 is not under pressure, the difference between the vertical distance d 2 between the first polar plate 204 and the second polar plate 205 and the vertical distance d 3 between the first polar plate 204 and the second polar plate 205 when the cover 203 is under pressure increases, so that the difference between the capacitance C 3 between the first polar plate 204 and the second polar plate 205 when the cover 203 is not under pressure and the capacitance C 4 between the first polar plate 204 and the second polar plate 205 when the cover 203 is under pressure also increases, and further the detection sensitivity Sens 2 of the capacitive detection structure provided by the embodiment of the present disclosure is also greater than the detection sensitivity Sens 1 of the capacitive detection structure in fig. 1, thereby improving the sensitivity of capacitive detection and the accuracy of capacitive detection.
FIG. 7 is a schematic illustration of a variation of the first cantilever beam when the cover is under pressure.
It should be understood that, although the first plate and the second plate are not parallel after the cover is pressed in the illustration, the change of the vertical distance between the first plate and the first plate is larger than the change of the vertical distance between the second plate and the first plate when the first plate is disposed on the side of the circuit board facing the base after the first cantilever beam is better extended. In the practical application process, the displacement of the first cantilever beam under the action of pressure, which drives the first polar plate to move towards the direction of the base, is far smaller than the vertical distance between the first polar plate and the second polar plate when the cover plate is not under pressure, so that the two polar plates can still be considered to be arranged in parallel.
Specifically, as shown in fig. 7, the O-point is located at the fixed end 216, the a-point is a pressure action point, and the B-point is the end of the first cantilever 206; OA length is L 1 and AB length is L 2. The cover 203 is subjected to a pressure at point a, which is F. During the compression of the cover 203, the first cantilever 206 is deformed by bending, the displacement of the downward movement under the compression at the point a is x 1, and the displacement of the downward movement under the compression at the point B is x 2. Where x 1 can theoretically be considered as the displacement of the cover 203 moving downward when the cover 203 is under pressure, and x 2 can theoretically be considered as the displacement of the first plate 204 moving toward the second plate 205 when the cover 203 is under pressure. According to the lever principle, if L 1：L2 = 1:1, then theoretically x1: x2 = 1:2.5. by extending the first cantilever beam 206, the displacement of the first polar plate 204 moving towards the second polar plate 205 when the cover plate 203 is under pressure can be amplified to 2.5 times of the displacement of the downward movement when the cover plate 203 is under pressure, so that the detection sensitivity is improved.
In some embodiments, the length of the second cantilever beam 207 in a direction parallel to the surface of the circuit board 202 is equal to the length of the fixed end 216 in a direction parallel to the surface of the circuit board 202.
Specifically, since the first cantilever beam 206 and the second cantilever beam 207 are all completely deformed during the movement of the cover plate 203 towards the second polar plate 205 under the action of pressure, the length of the second cantilever beam 207 along the direction parallel to the surface of the circuit board 202 is set to be equal to the length of the fixed end 216 along the direction parallel to the surface of the circuit board 202, so that the stability of the cover plate 203 and the circuit board 202 during the pressure can be ensured, and the overall stability of the capacitive detection structure is improved. In some other embodiments, the second cantilever beam 207 may be extended, the second cantilever beam 207 is divided into a fixed end 216 and an extended end 226, and the length of the first cantilever beam 206 along the direction parallel to the surface of the circuit board 202 is set equal to the length of the fixed end 216 of the second cantilever beam 207 along the direction parallel to the surface of the circuit board 202, which is not limited herein.
In some embodiments, the thickness of the first cantilever beam 206 and the second cantilever beam 207 is 0.01mm to 1mm. Specifically, 0.01mm～0.1mm、0.1mm～0.2mm、0.2mm～0.3mm、0.3mm～0.4mm、0.4mm～0.5mm、0.5mm～0.6mm、0.6mm～0.7mm、0.7mm～0.8mm、0.8mm～0.9mm mm to 1mm can be used. In this interval range, the first cantilever beam 206 and the second cantilever beam 207 have enough bending deformation degree to support the cover plate 203 and the polar plate to move, and meanwhile, the thicknesses of the first cantilever beam 206 and the second cantilever beam 207 cannot be too thick, so that the capacitive detection structure occupies more space, and the manufacturing cost of the capacitive detection structure is increased. In the practical application process, the thicknesses of the first cantilever beam 206 and the second cantilever beam 207 may be set according to actual needs, so long as the thicknesses of the first cantilever beam 206 and the second cantilever beam 207 can meet the requirement that the cover plate 203 and the polar plate can be supported for movement, and the thickness is not limited herein.
In some embodiments, the first cantilever beam 206 and the second cantilever beam 207 are each made of stainless steel. Specifically, the stainless steel has good supporting property, so that the first cantilever beam 206 and the second cantilever beam 207 can be fixedly connected, and the first polar plate 204 is arranged on the first cantilever beam 206, and on the other hand, the stainless steel has elasticity, and when the cover plate 203 is pressed, the first cantilever beam 206 is bent and deformed, so that the first polar plate 204 is driven to move towards the second polar plate 205. In some other embodiments of the present invention, other materials may be used to make the first cantilever beam 206 and the second cantilever beam 207, which are not limited herein.
In some embodiments, the vertical separation distance between the first plate 204 and the second plate 205 is 0.3mm to 3mm when the cover 203 is not under load. Specifically, the thickness of the material may be 0.3mm to 0.5mm, 0.5mm to 0.8mm, 0.8mm to 1.1mm, 1.1mm to 1.4mm, 1.4mm to 1.7mm, 1.7mm to 2.0mm, 2.0mm to 2.3mm, 2.3mm to 2.6mm or 2.6mm to 3mm. In this interval range, when the first polar plate 204 is driven to move towards the second polar plate 205, the interval between the first polar plate 204 and the second polar plate 205 changes, so that the capacitance value between the first polar plate 204 and the second polar plate 205 changes, and meanwhile, the interval distance between the first polar plate 204 and the second polar plate 205 is not too large, so that the whole occupied space of the capacitive detection structure is not too large.
In the embodiment of the present disclosure, the thickness of the first plate 204 and the second plate 205 is 0.01mm to 1mm. Specifically, 0.01mm～0.05mm、0.05mm～0.1mm、0.1mm～0.15mm、0.15mm～0.2mm、0.2mm～0.25mm、0.25mm～0.3mm、0.3mm～0.35mm、0.35mm～0.4mm、0.4mm～0.45mm、0.45mm～0.5mm、0.5mm～0.55mm、0.55mm～0.6mm、0.65mm～0.7mm、0.7mm～0.75mm、0.75mm～0.8mm、0.8mm～0.85mm、0.85mm～0.9mm、0.9mm～0.95mm mm to 1mm can be used. In this thickness range, on the one hand, a lightweight capacitive sensing structure is advantageously formed, and in the case of providing a thinner plate, the pressure applied to the cover plate 203 by sensing the capacitance change can be satisfied. On the other hand, in this range, since the first polar plate 204 and the second polar plate 205 are all moved downwards under the pressure in the process of pressing the cover plate 203, a certain interval distance needs to be set between the first polar plate 204 and the second polar plate 205 to ensure that a certain change occurs in the vertical distance between the first polar plate 204 and the second polar plate 205, and thus, the capacitance changes, and meanwhile, the first polar plate 204 is not contacted with the second polar plate 205, so that a short circuit of the capacitance structure is caused, and the performance of the capacitance structure is ensured. Wherein the thickness of the first plate 204 and the second plate 205 is much smaller than the vertical distance between the first plate 204 and the second plate 205. In the disclosed embodiments, both the first plate 204 and the second plate 205 may be provided as metal plates.
In some embodiments, further comprising: two pads 208, the two pads 208 are disposed between the first cantilever beam 206 and the circuit board 202 and between the second cantilever beam 207 and the circuit board 202, respectively. The thickness of the spacer 208 is 0.3 mm-2 mm. Specifically, the thickness of the sheet may be 0.3mm to 0.6mm, 0.6mm to 0.9mm, 0.9mm to 1.2mm, 1.2mm to 1.5mm, 1.5mm to 1.8mm, or 1.8mm to 2.1mm, and is not limited thereto. In some embodiments, the pad 208 may be provided as a film layer, or may be formed by stacking film layers with the same thickness or different thicknesses, and the thickness of the pad 208 may be selected according to the requirements of the actual capacitive sensing structure during the specific application, which is not limited herein. In the embodiment of the present disclosure, the length of the spacer 208 may be set smaller than the length of the first polar plate 204 or the second polar plate 205, so that the overall occupied space of the capacitive detection structure is smaller, and meanwhile, the manufacturing cost of the capacitive detection structure is further saved.
In some embodiments, further comprising: a shielding layer disposed within the circuit board 202; wherein the cross-sectional area of the shielding layer is the same as the cross-sectional area of the circuit board 202.
Specifically, in the detection process, when a conductive medium is used to apply pressure to the cover 203, the conductive medium may interfere with the electric field around the capacitive structure, thereby affecting the capacitive detection structure, because the thickness of the cover 203 and the thickness of the circuit board 202 are relatively thin. A shielding layer is disposed in the electrode plate 202 to isolate the influence of the conductive medium on the capacitor structure.
Setting the cross-sectional area of the shielding layer to be the same as the cross-sectional area of the circuit board 202 can further improve the shielding ability of the shielding layer to the conductive medium, and facilitate assembly of the capacitive detection structure.
In particular, the shielding layer may be provided as a grounded copper sheet. The copper sheet has low material cost, convenient manufacture and good conductivity, and the shielding layer is arranged as the grounded copper sheet, so that the manufacturing cost of the capacitive detection structure can be further reduced.
In some other embodiments, the shielding layer may be made of other shielding materials, such as conductive foam, a grounding aluminum sheet, etc., as long as the shielding layer can isolate the conductive medium from influencing the capacitance detection structure, which is not limited herein.
According to some embodiments of the present disclosure, another aspect of the embodiments of the present disclosure further provides an electronic device, which is the same as or corresponding to the previous embodiment, and reference may be made to the corresponding description of the previous embodiment, and detailed description thereof will be omitted.
Another aspect of the embodiments of the present disclosure further provides an electronic device including: the capacitive detection structure of any one of the above embodiments; and the processor is configured to acquire the capacitance value variation when the cover plate is subjected to pressure and detect the pressure applied to the cover plate based on the capacitance value variation.
Specifically, the electronic device may be an electronic product with a touch screen, such as a mobile phone, a tablet computer, or a touch screen with a touch interaction display terminal, such as a vending machine, a signal display terminal, etc.
According to the embodiment of the disclosure, when pressure is applied to the cover plate, the capacitance of the capacitance structure formed by the first polar plate, the second polar plate and the conducting strip is detected, the change value of the vertical distance between the first polar plate, the second polar plate and the conducting strip is calculated when the cover plate is not subjected to the pressure and the cover plate is subjected to the pressure, and then the pressure applied to the cover plate is calculated.
In the technical scheme of the capacitive detection structure provided by the embodiment of the disclosure, a base and a cover plate positioned right above the base are spaced, and the cover plate is used for bearing pressure; the circuit board is positioned on one surface of the cover plate facing the base; the first cantilever beam and the second cantilever beam are respectively and fixedly connected to two opposite ends of one surface of the circuit board, which is far away from the cover plate; the length of the first cantilever beam along the direction parallel to the surface of the circuit board is longer than the length of the second cantilever beam along the direction parallel to the surface of the circuit board; the first pole plate is fixedly connected to one surface of the first cantilever beam, which faces the base, and the second pole plate is positioned on one surface of the base, which faces the circuit board. According to the embodiment of the disclosure, the cantilever beam is prolonged, the lever principle is utilized, and therefore in the process that the cover plate receives pressure, the downward moving distance of the first polar plate arranged on one face of the first cantilever beam, which faces the base, is larger than the downward moving distance of the cover plate, according to the calculation formula of the capacitance, the capacitance variation between the two polar plates is increased compared with that of the first polar plate arranged on one face of the cover plate, which faces the base, and then the pressure received by the cover plate is calculated according to the calculation formula of the pressure, so that the sensitivity of capacitance detection can be improved.
It will be understood by those of ordinary skill in the art that the foregoing embodiments are specific examples of implementing the disclosure, and that various changes in form and details may be made therein without departing from the spirit and scope of the disclosure. Various changes and modifications may be made by one skilled in the art without departing from the spirit and scope of the disclosure, and the scope of the disclosure should therefore be assessed as that of the appended claims.
Claims (10)
1. A capacitive sensing structure, comprising:
the device comprises a base and a cover plate positioned right above the base, wherein the base is spaced from the cover plate, and the cover plate is used for bearing pressure;
the circuit board is positioned on one surface of the cover plate, which faces the base;
The first cantilever beam and the second cantilever beam are respectively and fixedly connected to two opposite ends of one surface of the circuit board, which is far away from the cover plate; the length of the first cantilever beam along the direction parallel to the surface of the circuit board is longer than the length of the second cantilever beam along the direction parallel to the surface of the circuit board;
The circuit board comprises a base, a first cantilever beam, a second cantilever beam, a first polar plate and a second polar plate, wherein a right-facing area is arranged between the first polar plate and the second polar plate, the first polar plate is fixedly connected to one surface of the first cantilever beam, which faces the base, and the second polar plate is positioned on one surface of the base, which faces the circuit board.
2. The capacitive sensing structure of claim 1, wherein said first and second cantilevers Liang Yuanli are fixedly attached to an outer sidewall at one end of said circuit board, said first and second cantilevers are both deformed by bending as said cover is subjected to pressure, and said first cantilever drives said first plate to move toward said second plate.
3. The capacitive sensing structure of claim 2, wherein said first cantilever beam comprises:
The circuit board comprises a fixed end and an extension end, wherein one end of the fixed end is fixedly connected with the outer side wall, one end of the extension end, which is far away from the outer side wall, is fixedly connected with the fixed end, and the extension end extends along a direction parallel to the surface of the circuit board.
4. A capacitive sensing structure according to claim 3, wherein the length of the second cantilever beam in a direction parallel to the surface of the circuit board is equal to the length of the fixed end in a direction parallel to the surface of the circuit board.
5. The capacitive sensing structure of claim 1, further comprising:
the two gaskets are respectively arranged between the first cantilever beam and the circuit board and between the second cantilever beam and the circuit board.
6. The capacitive sensing structure of claim 5, wherein said spacer has a thickness of 0.3mm to 2mm.
7. The capacitive sensing structure of claim 1, wherein said first cantilever beam and said second cantilever beam have a thickness of 0.01mm to 1mm.
8. The capacitive sensing structure of claim 1, wherein said first cantilever beam and said second cantilever beam are each fabricated from stainless steel.
9. The capacitive sensing structure of claim 1, further comprising:
The shielding layer is arranged in the circuit board; wherein, the cross-sectional area of shielding layer is the same as the cross-sectional area of circuit board.
10. An electronic device, comprising: a capacitive sensing structure as claimed in any one of claims 1 to 9; and the processor is configured to acquire the capacitance value variation when the cover plate is subjected to pressure and detect the pressure applied to the cover plate based on the capacitance value variation.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202410215747.2A CN118089990A (en) | 2024-02-27 | 2024-02-27 | Capacitive detection structure and electronic equipment |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202410215747.2A CN118089990A (en) | 2024-02-27 | 2024-02-27 | Capacitive detection structure and electronic equipment |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN118089990A true CN118089990A (en) | 2024-05-28 |
Family
ID=91161083
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202410215747.2A Pending CN118089990A (en) | 2024-02-27 | 2024-02-27 | Capacitive detection structure and electronic equipment |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN118089990A (en) |
-
2024
- 2024-02-27 CN CN202410215747.2A patent/CN118089990A/en active Pending
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP2005508533A (en) | Force sensor and touch panel using the same | |
| US8621942B2 (en) | Force sensor with compressible electrode | |
| US7353713B2 (en) | Flexible apparatus and method to enhance capacitive force sensing | |
| CN103226418B (en) | With the capacitive type touch pad of keyswitch | |
| CN102053750A (en) | Sensing device and electronic device | |
| US20120019479A1 (en) | Touch pad for multiple sensing | |
| CN115485648B (en) | System and method for detecting and characterizing touch input at a human-machine interface | |
| JP2015529989A (en) | Capacitance sensor that detects the movement of an object | |
| CN110703935B (en) | Touch panel | |
| CN107076626B (en) | Capacitive force transducer | |
| CN108318159B (en) | Capacitive force sensor with improved fixation | |
| CN113282192A (en) | Pressure-sensitive module and electronic equipment | |
| CN118089990A (en) | Capacitive detection structure and electronic equipment | |
| US11953400B2 (en) | Input device including improved pressure sensing unit design | |
| WO2023221515A1 (en) | Touch device | |
| US7921728B2 (en) | Flexible apparatus and method to enhance capacitive force sensing | |
| CN117572987A (en) | Capacitive detection structure and electronic equipment | |
| CN117539366A (en) | Capacitive detection structure and electronic equipment | |
| CN100416217C (en) | Thickness detecting sensor | |
| US20210173500A1 (en) | Capacitive touch sensor | |
| JP2019090729A (en) | Capacitive pressure sensor | |
| JPH085482A (en) | Electrostatic capacity type tactile sensor | |
| KR20140136353A (en) | Capacitive Force-based Input Device Using Elasticity of Housing | |
| US10996118B2 (en) | Sensor apparatus | |
| CN117093093A (en) | Electronic device and method for detecting pressing force |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |