CN112461433A - Capacitive pressure sensing device and electronic equipment - Google Patents

Abstract

The embodiment of the application provides a capacitive pressure sensing device and electronic equipment, wherein the capacitive pressure sensing device comprises an elastic carrier, a first capacitor plate and a second capacitor plate, the elastic carrier is in a surrounding form and comprises a first end face and a second end face which are respectively positioned at two ends of the elastic carrier, and the first end face and the second end face are mutually staggered; the first capacitor plate is arranged on the elastic carrier along the direction from the first end face to the second end face; the second capacitor plate is arranged on the elastic carrier along the direction from the second end face to the first end face, and the overlapping area of the first capacitor plate and the second capacitor plate in the radial direction of the elastic carrier changes along with the deformation of the elastic carrier. The capacitive pressure sensing device provided by the embodiment of the application can sense the pressure acting on any position of the circumferential direction of the elastic carrier, and the pressure sensing area is greatly increased.

Description

Capacitive pressure sensing device and electronic equipment

Technical Field

The invention relates to the technical field of sensors, in particular to a capacitive pressure sensing device and electronic equipment.

Background

A capacitive pressure sensor is a pressure sensor that uses a capacitance as a sensing element to convert a measured pressure into a change in capacitance. At present, a circular metal film or a metal-plated film is generally adopted by a capacitive pressure sensor on the market as two electrode plates of a capacitor, when the distance between the two electrode plates is changed due to the fact that the electrode plates sense pressure, capacitance formed between the two electrode plates is changed, and an electric signal which has a certain relation with the capacitance can be output through a measuring circuit. However, the capacitive pressure sensor with such a structure can only detect a pressing acting on an electrode plate or a plane where the electrode plate is located, and for other pressing in some directions, such as pressing acting between two electrode plates, the pressure sensor cannot accurately sense the pressing, so that the pressure sensing area of the existing pressure sensor is small, and the capability of detecting the pressing in different directions is limited.

Disclosure of Invention

An object of the present application is to provide a capacitive pressure sensing device and an electronic apparatus, so as to solve the above problems. The present application achieves the above object by the following technical solutions.

In a first aspect, an embodiment of the present application provides a capacitive pressure sensing device, including an elastic carrier, a first capacitive plate, and a second capacitive plate, where the elastic carrier is in a closed shape, and includes a first end face and a second end face respectively located at two ends of the elastic carrier, and the first end face and the second end face are staggered with each other; the first capacitor plate is arranged on the elastic carrier along the direction from the first end face to the second end face; the second capacitor plate is arranged on the elastic carrier along the direction from the second end face to the first end face, and the overlapping area of the first capacitor plate and the second capacitor plate in the radial direction of the elastic carrier changes along with the deformation of the elastic carrier.

In a second aspect, an embodiment of the present application provides an electronic device, which includes a housing and the capacitive pressure sensing device of the first aspect, where the capacitive pressure sensing device is disposed in the housing.

Compared with the prior art, the capacitive pressure sensing device provided by the embodiment of the application comprises an elastic carrier, a first capacitor plate and a second capacitor plate, wherein the elastic carrier can be pressed to deform, the overlapping area of the first capacitor plate and the second capacitor plate in the radial direction of the elastic carrier changes along with the deformation of the elastic carrier, and then the capacitance of a capacitor formed by the first electrode plate and the second electrode plate changes, so that the pressure acting on the elastic carrier can be sensed by detecting the capacitance, and the pressure sensing function is realized. In addition, the elastic carrier can be deformed by pressing at any position in the circumferential direction of the elastic carrier, so that the capacitive pressure sensing device can sense the pressure acting at any position in the circumferential direction of the elastic carrier, and the pressure sensing area is greatly increased.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

Fig. 1 is a schematic structural diagram of a capacitive pressure sensing device according to an embodiment of the present disclosure.

FIG. 2 is a cross-sectional view along A-A of the capacitive pressure sensing device provided by the embodiment shown in FIG. 1.

FIG. 3 is a cross-sectional view along A-A of the capacitive pressure sensing device provided by the embodiment shown in FIG. 1 when pressurized.

FIG. 4 is a cross-sectional view of a capacitive pressure sensing device according to another embodiment of the present application.

FIG. 5 is a cross-sectional view of the capacitive pressure sensing device provided in the embodiment of FIG. 4 when under pressure.

FIG. 6 is a cross-sectional view of a capacitive pressure sensing device according to yet another embodiment of the present application.

FIG. 7 is a cross-sectional view of a capacitive pressure sensing device according to yet another embodiment of the present application.

FIG. 8 is a partial cross-sectional view of a capacitive pressure sensing device according to yet another embodiment of the present application.

Fig. 9 is a further cross-sectional view of a capacitive pressure sensing device provided by an embodiment of the present application.

Fig. 10 is a cross-sectional view of an electronic device provided in an embodiment of the present application.

Detailed Description

Reference will now be made in detail to embodiments of the present application, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the accompanying drawings are illustrative and are only for the purpose of explaining the present application and are not to be construed as limiting the present application.

In order to make the technical solutions better understood by those skilled in the art, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. It is to be understood that the embodiments described are only a few embodiments of the present application and not all 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 application.

Referring to fig. 1 and fig. 2, a capacitivepressure sensing device 100 according to an embodiment of the present disclosure includes anelastic carrier 110, a firstcapacitive plate 120, and a secondcapacitive plate 130, where theelastic carrier 110 is in a surrounding shape, theelastic carrier 110 includes afirst end surface 111 and asecond end surface 112 respectively located on theelastic carrier 110, and thefirst end surface 111 and thesecond end surface 112 are staggered.

Thefirst capacitor plate 120 is along the direction from thefirst end surface 111 to the second end surface 112 (refer to the first direction X)₁) Disposed on theelastic carrier 110, thesecond capacitor plate 130 extends along the direction from thesecond end surface 112 to the first end surface 111 (refer to the second direction X)₂) The overlapping area of thefirst capacitor plate 120 and thesecond capacitor plate 130 on theelastic carrier 110 in the radial direction of theelastic carrier 110 varies with the deformation of theelastic carrier 110.

In this embodiment, theelastic carrier 110 may be a fully-enclosed structure to form an enclosed form, and thefirst end surface 111 and thesecond end surface 112 are located at two circumferential ends of theelastic carrier 110. In some embodiments, theelastic carrier 110 may also be a non-fully-enclosed structure when not pressed, for example, thefirst end surface 111 and thesecond end surface 112 are oppositely disposed to form an opening when theelastic carrier 110 is not pressed, after theelastic carrier 110 is pressed, thefirst end surface 111 and thesecond end surface 112 move in opposite directions, and theelastic carrier 110 forms a fully-enclosed structure.

Theelastic carrier 110 is used for bearing an external pressure, and under the action of the external pressure, theelastic carrier 110 deforms, so as to drive the overlapping area of thefirst capacitor plate 120 and thesecond capacitor plate 130 in the radial direction of theelastic carrier 110 to change. After the external pressure disappears, theelastic carrier 110 is restored to its original shape by the elastic restoring force, and the first andsecond capacitor plates 120 and 130 can be restored to their original positions.

For example, as shown in fig. 2 and 3, when theelastic carrier 110 is not subjected to the external pressure, thefirst capacitor plate 120 and thesecond capacitor plate 130 are located at the initial position, and the overlapping area of thefirst capacitor plate 120 and thesecond capacitor plate 130 in the radial direction of theelastic carrier 110 may be S₁₁. When theelastic carrier 110 is under the action of the external pressure, theelastic carrier 110 may be folded and deformed, thefirst capacitor plate 120 and thesecond capacitor plate 130 move synchronously, and the overlapping area of thefirst capacitor plate 120 and thesecond capacitor plate 130 in the radial direction of theelastic carrier 110 may be S₁₂。

The overlapping portion of thefirst capacitor plate 120 and thesecond capacitor plate 130 in the radial direction of theelastic carrier 110 may form a capacitor, according to the capacitance calculation formula: c ═ S/d, where C is the capacitance size and S is the overlapping area of thefirst electrode plate 120 and thesecond electrode plate 130 in the radial direction of the elastic carrier 110 (e.g., S₁₁Or S₁₂) D is a distance between thefirst electrode plate 120 and thesecond electrode plate 130 in the radial direction of theelastic carrier 110, and ε is a dielectric constant of the dielectric layer between thefirst electrode plate 120 and the second electrode plate 130)₁₁Is changed into S₁₂) The capacitance magnitude C of the capacitor changes. Therefore, the pressure acting on theelastic carrier 110 will cause the capacitance between thefirst electrode plate 120 and thesecond electrode plate 130 to change, and the capacitivepressure sensing device 100 can sense the pressure acting on theelastic carrier 110 by sensing the capacitance, thereby implementing the pressure sensing function. Since theelastic carrier 110 can be deformed by pressing at any position of the circumference of theelastic carrier 110, and then the pressure is sensed by the capacitivepressure sensing device 100, the capacitivepressure sensing device 100 can detect the pressure acting on any position of the circumference of theelastic carrier 110, and the pressure sensing area is greatly increased.

Theelastic carrier 110 may be compressedDrawing thefirst end surface 111 and thesecond end surface 112 in opposite directions, for example, thefirst end surface 111 moves in the second direction X₂Moving, thesecond end surface 112 is along the first direction X₁And (4) moving. The overlapping area of thefirst capacitor plate 120 and thesecond capacitor plate 130 in the radial direction of theelastic carrier 110 may be positively correlated with the pressure applied to theelastic carrier 110.

As an example, when theelastic carrier 110 is not subjected to the external pressure, the overlapping area of thefirst capacitor plate 120 and thesecond capacitor plate 130 in the radial direction of theelastic carrier 110 is the smallest (e.g., S)₁₁) (ii) a After theelastic carrier 110 is pressed, the overlapping area of thefirst capacitor plate 120 and thesecond capacitor plate 130 in the radial direction of theelastic carrier 110 is larger (e.g. S) as the pressure is increased₁₁Increase to S₁₂) And the capacitance formed by thefirst capacitor plate 120 and thesecond capacitor plate 130 is positively correlated with the overlapping area of thefirst capacitor plate 120 and thesecond capacitor plate 130 in the radial direction of theelastic carrier 110, and the variation trend of the external pressure value can be directly judged according to the variation trend of the capacitance value at the moment, for example, when the capacitance value is increased, the external pressure value can be determined to be increased, when the capacitance value is decreased, the external pressure is also decreased, and the detection result is clear and visual.

Certainly, the magnitude of the external pressure value may also be calculated according to the magnitude of the capacitance value, for example, the capacitivepressure sensing device 100 may further include a storage module (not shown), where the storage module prestores a mapping table of capacitance values and pressure values, and different capacitance values in the mapping table correspond to different pressure values, when the capacitivepressure sensing device 100 obtains one capacitance value, the capacitance value may be searched in the mapping table, and the found pressure value corresponding to the capacitance value is used as the detected external pressure value, so that the magnitude of the external pressure value may be obtained according to the detected magnitude of the capacitance value. In some embodiments, the storage module may also pre-store a relationship between the capacitance value and the pressure value, and the pressure value may be directly calculated after inputting a capacitance value according to the relationship.

Referring to fig. 4 and 5, in some embodiments, the overlapping area of thefirst capacitor plate 120 and thesecond capacitor plate 130 in the radial direction of theelastic carrier 110 may also be inversely related to the pressure applied to theelastic carrier 110.

For example, when theelastic carrier 110 is not subjected to the external pressure, the overlapping area of thefirst capacitor plate 120 and thesecond capacitor plate 130 in the radial direction of theelastic carrier 110 is the largest (e.g., S)₂₁). After theelastic carrier 110 is pressed, the overlapping area of thefirst capacitor plate 120 and thesecond capacitor plate 130 in the radial direction of theelastic carrier 110 is smaller as the pressure is increased (e.g., S is smaller)₂₁Is reduced to S₂₂) Therefore, the smaller the capacitance formed by thefirst capacitor plate 120 and thesecond capacitor plate 130 is, the smaller the external pressure value can be obtained by detecting the capacitance value through a pre-established mapping table of the capacitance value and the pressure value or a relationship between the capacitance value and the pressure value.

Still referring to fig. 1 and 2, theelastic carrier 110 may include afirst layer 113 and asecond layer 114 spaced apart from each other along a radial direction of theelastic carrier 110, thefirst layer 113 includes afirst end surface 111, thesecond layer 114 includes asecond end surface 112, thefirst capacitor plate 120 is disposed on thefirst layer 113, and thesecond capacitor plate 130 is disposed on thesecond layer 114.

The capacitivepressure sensing device 100 respectively supports the firstcapacitive plate 120 and the secondcapacitive plate 130 through thefirst layer 113 and thesecond layer 114, and when theelastic carrier 110 is compressed and folded, thefirst layer 113 and thesecond layer 114 move in opposite directions, so as to drive the overlapping area of the firstcapacitive plate 120 and the secondcapacitive plate 130 in the radial direction of theelastic carrier 110 to change.

Theelastic carrier 110 may further include aconnection portion 115, thefirst layer 113, theconnection portion 115, and thesecond layer 114 are sequentially connected and form a surrounding shape, and theconnection portion 115 may serve as a support seat to fix the capacitivepressure sensing device 100. For example, when the capacitivepressure sensing apparatus 100 is used to detect a pressing force acting on an electronic device housing, the connectingportion 115 may be fixedly connected to the electronic device housing, so as to complete the assembly and fixation of the capacitivepressure sensing apparatus 100, and when theelastic carrier 110 is pressed, theelastic carrier 110 deforms with a joint of the connectingportion 115 and the electronic device housing as a fulcrum.

Theelastic carrier 110 may be anelastic band 116, and theelastic carrier 110 is a spiral structure formed by theelastic band 116 being curled. In some embodiments, the outer diameter of theelastic carrier 110 can be changed by the degree of curling of the spiral structure, so that theelastic carrier 110 can be accommodated in shells with different inner diameters, pressure detection on the shells is realized, and the universality is high. In addition, the spiral structure can ensure that theelastic carrier 110 can be folded and deformed (the curling degree is increased) after being pressed, and can be restored (the curling degree is reduced) after the external force is removed, so that the elastic deformation capability of theelastic carrier 110 is enhanced.

Theelastic band body 116 may be formed by winding to form theelastic carrier 110 in a spiral structure, and thefirst layer 113 and thesecond layer 114 may be respectively located at two free ends of theelastic carrier 110 in the circumferential direction. When theelastic carrier 110 is a spiral structure, thefirst layer 113, the connectingportion 115 and thesecond layer 114 are all arc-shaped plates, and the sum of the arc lengths of thefirst layer 113, the connectingportion 115 and thesecond layer 114 is equal to the length of theelastic belt body 116.

In this embodiment, one side of thefirst capacitor plate 120 may be flush with thefirst end surface 111, and the other side of thefirst capacitor plate 120 is along the direction from thefirst end surface 111 to the second end surface 112 (refer to the first direction X)₁) And (4) extending. One side of thesecond capacitor plate 130 may be flush with thesecond end surface 112, and the other side of thesecond capacitor plate 130 is along the direction from thesecond end surface 112 to the first end surface 111 (refer to the second direction X)₂) And (4) extending.

In some embodiments, thefirst capacitor plate 120 may also protrude from thefirst end surface 111 or be recessed from thefirst end surface 111 in a direction from thefirst end surface 111 to thesecond end surface 112. Thesecond capacitor plate 130 may also protrude from thesecond end surface 112, or retract from thesecond end surface 112 along the direction from thesecond end surface 112 to thefirst end surface 111.

In this embodiment, the arc length of thefirst capacitor plate 120 and the arc length of thesecond capacitor plate 130 may be set according to actual requirements, as long as it is ensured that thefirst capacitor plate 120 and thesecond capacitor plate 130 have enough gap in the circumferential direction of theelastic carrier 110, so that thefirst capacitor plate 120 and thesecond capacitor plate 130 are kept insulated from each other.

Referring to fig. 6, in some embodiments, theelastic carrier 110 may also be a frame structure. Specifically, the connectingportion 115 includes a first connectingarm 1151, a second connectingarm 1152 and a connectingbase plate 1153, the first connectingarm 1151 and the second connectingarm 1152 are oppositely disposed, and the connectingbase plate 1153 is connected between the first connectingarm 1151 and the second connectingarm 1152 and is angularly connected with the first connectingarm 1151 and the second connectingarm 1152, for example, the first connectingarm 1151 and the second connectingarm 1152 may be perpendicular to the connectingbase plate 1153.

Thefirst layer 113 and thesecond layer 114 may be both arc-shaped plates, thefirst layer 113 is connected to a side of the first connectingarm 1151 away from the connectingbase plate 1153, thesecond layer 114 is connected to a side of the second connectingarm 1152 away from the connectingbase plate 1153, and centers of circles of thefirst layer 113 and thesecond layer 114 are located in theelastic carrier 110. When the connectingbottom plate 1153 is used as a fulcrum, theelastic carrier 110 can be pressed and folded by pressing thefirst layer 113, thesecond layer 114, the first connectingarm 1151 or the second connectingarm 1152, and when thefirst layer 113 or thesecond layer 114 is used as a fulcrum, theelastic carrier 110 can be pressed and folded by pressing the connectingbottom plate 1153, so as to be sensed by the capacitivepressure sensing device 100. Therefore, when theelastic carrier 110 is a frame structure, the capacitivepressure sensing apparatus 100 can also sense the pressure acting on any position in the circumferential direction of theelastic carrier 110.

Referring to fig. 7, in some embodiments, when theelastic carrier 110 has a spiral structure, theelastic carrier 110 may further include athird layer 117, the number of thethird layers 117 may be one or more, and thefirst layer 113, thesecond layer 114, and thethird layer 117 may be sequentially arranged along a radial direction of theelastic carrier 110. Thefirst capacitor plate 120 may be disposed on thefirst layer 113 and thesecond layer 114, thesecond capacitor plate 130 may be disposed on thethird layer 117, and thefirst capacitor plate 120 and thesecond capacitor plate 130 are spaced apart by a set distance in a circumferential direction of theelastic carrier 110 to achieve insulation.

In this embodiment, when at least one of the central angles corresponding to thefirst capacitor plate 120 and thesecond capacitor plate 130 is smaller than 360 °, the effective area of the capacitor formed by thefirst capacitor plate 120 and thesecond capacitor plate 130 is equal to the area of the capacitor plate with the smallest arc length. Taking fig. 7 as an example, if the central angle degree corresponding to thesecond capacitor plate 130 is less than 360 °, and the arc length of thesecond capacitor plate 130 is less than the arc length of thefirst capacitor plate 120, the effective area of the capacitor formed by thefirst capacitor plate 120 and thesecond capacitor plate 130 is equal to the area of thesecond capacitor plate 130. When the central angle degrees corresponding to thefirst capacitor plate 120 and thesecond capacitor plate 130 are both greater than 360 degrees, the effective area of the capacitor formed by thefirst capacitor plate 120 and thesecond capacitor plate 130 is the area of a single turn (the central angle degree is equal to 360 degrees) of the capacitor plate located in the inner layer.

In this embodiment, thefirst capacitor plate 120 and thesecond capacitor plate 130 may be flexible electrode films, and thefirst capacitor plate 120 and thesecond capacitor plate 130 may have a certain bending deformation capability by reducing the thickness, and may be deformed synchronously with theelastic carrier 110 under the driving of theelastic carrier 110.

In some embodiments, the material of thefirst capacitor plate 120 and thesecond capacitor plate 130 may be formed by one or more of gold, platinum, nickel, silver, indium, and conductive carbon, and thefirst capacitor plate 120 and thesecond capacitor plate 130 may be formed on theelastic carrier 110 by printing, bonding, or the like.

Still referring to fig. 2, thefirst layer 113 at least partially overlaps thesecond layer 114 in the radial direction of theelastic carrier 110 when theelastic carrier 110 is uncompressed. For example, thefirst layer 113 is located at an outer layer of theelastic carrier 110, thesecond layer 114 is located at an inner layer of theelastic carrier 110, and thefirst layer 113 and thesecond layer 114 partially overlap in a radial direction of theelastic carrier 110. Thus, when theelastic carrier 110 is compressed, thefirst layer 113 can move along thesecond layer 114, and thesecond layer 114 can move along thefirst layer 113, so that thefirst layer 113 and thesecond layer 114 can be guided, so that theelastic carrier 110 is subjected to furling deformation with an increasing degree of curling after being compressed, and other deformation, such as the squashing of theelastic carrier 110, does not occur.

Thefirst layer 113 may include afirst surface 1131, thesecond layer 114 may include asecond surface 1141, thefirst surface 1131 and thesecond surface 1141 are located on the same side of theflexible carrier 110, thefirst capacitor plate 120 is attached to thefirst surface 1131, thesecond capacitor plate 130 is attached to thesecond surface 1141, and theflexible carrier 110 is made of a flexible dielectric material. The portion of theelastic carrier 110 located between thefirst capacitor plate 120 and thesecond capacitor plate 130 serves as an insulating dielectric layer of the capacitor, and the overlapping portion of thefirst capacitor plate 120, theelastic carrier 110 and thesecond capacitor plate 130 in the radial direction of theelastic carrier 110 constitutes a capacitor. In this embodiment, theelastic carrier 110 can be used for receiving external pressure and also can serve as an insulating medium layer for forming a capacitor, and the structural design is ingenious and practical.

Theelastic carrier 110 may be made of rubber or materials such as Polyethylene (PE), thermoplastic elastomer (TPE), and Polyethylene terephthalate (pet) elasticity, which meet the requirement of the insulating electrolyte and have a certain flexibility, so that theelastic carrier 110 can be bent and deformed after theelastic carrier 110 is made.

Referring to fig. 8, in some embodiments, thefirst layer 113 includes afirst surface 1131, thesecond layer 114 includes asecond surface 1141, thefirst surface 1131 and thesecond surface 1141 are located on opposite sides of theflexible carrier 110, thefirst capacitor plate 120 is attached to thefirst surface 1131, thesecond capacitor plate 130 is attached to thesecond surface 1141, and thedielectric layer 140 is disposed between thefirst capacitor plate 120 and thesecond capacitor plate 130. The overlapping portions of thefirst capacitor plate 120, thesecond capacitor plate 130 and thedielectric layer 140 in the radial direction of theflexible carrier 110 constitute a capacitor.

In this embodiment, theelastic carrier 110 may be made of any elastic material, as long as thefirst capacitor plate 120 and thesecond capacitor plate 130 are insulated from each other, and whether the requirement of the insulating dielectric medium is met or not is not considered, and the selectable range of the material is increased. Thedielectric layer 140 may be an air layer, or an insulating dielectric layer with certain elasticity such as polyethylene, polyvinyl chloride, and polyethylene terephthalate, so that thedielectric layer 140 has certain deformation capability and can deform synchronously with theelastic carrier 110.

In some embodiments, when thedielectric layer 140 is an air layer, thedielectric layer 140 is formed by thefirst capacitor plate 120 and thesecond capacitor plate 130 being spaced apart from each other in the radial direction of theflexible carrier 110. When thedielectric layer 140 is an insulating dielectric layer, thedielectric layer 140 may be attached to thefirst capacitor plate 120 or thesecond capacitor plate 130 and located between thefirst capacitor plate 120 and thesecond capacitor plate 130, and the arc length of thedielectric layer 140 may be equal to the capacitor plate with the smallest arc length.

Referring to fig. 9, the capacitivepressure sensing apparatus 100 may further include apressing portion 150, thepressing portion 150 abuts against theelastic carrier 110, and theelastic carrier 110 may be deformed by pressing thepressing portion 150. Thepressing part 150 serves to increase a pressure bearing surface of the capacitivepressure sensing device 100 so that the capacitivepressure sensing device 100 can sense pressure acting outside theelastic carrier 110, not limited to sensing pressure acting on theelastic carrier 110.

Thepressing portion 150 may include apressing plate 151 and a supportingplate 152 disposed oppositely, and theelastic carrier 110 is abutted between thepressing plate 151 and the supportingplate 152. Thepressing plate 151 is used for bearing pressure, and the supportingplate 152 is used for fixing theelastic carrier 110, so that theelastic carrier 110 can be folded and deformed after being pressed, rather than moving integrally.

When the capacitivepressure sensing apparatus 100 is used to sense pressure acting on an electronic device, thepressing plate 151 may be attached to a pressure receiving surface of the electronic device, for example, when the pressure receiving surface of the electronic device is a plane, thepressing plate 151 may be a flat plate structure; when the pressed surface of the electronic device is an arc surface, thepressing plate 151 can be an arc plate structure, so that any position of the pressed surface can be pressed and transmitted to theelastic carrier 110 through thepressing plate 151, theelastic carrier 110 is deformed, and the capacitivepressure sensing device 100 can sense the pressure acting on any position of the pressed surface.

The number of thesupport plates 152 may be one or more, and when the number of thesupport plates 152 is one, thesupport plates 152 may be disposed opposite to thepressing plate 151. When the number of the supportingplates 152 is plural, the supportingplates 152 may be arranged along the circumferential direction of theelastic carrier 110 and all abut against theelastic carrier 110, so as to limit theelastic carrier 110, and prevent theelastic carrier 110 from being compressed and then not being folded and deformed but being flattened.

Theelastic carrier 110 may further have acavity 119, the capacitivepressure sensing apparatus 100 may further include a limitingmember 160, the limitingmember 160 is disposed in thecavity 119, and the limitingmember 160 may abut against theelastic carrier 110 when theelastic carrier 110 deforms, so as to prevent theelastic carrier 110 from being squashed due to an excessive external pressure.

The position-limitingmember 160 may have a substantially cylindrical structure, an axial direction of the position-limitingmember 160 is the same as an axial direction of theelastic carrier 110, and a size of the position-limitingmember 160 may be adaptively adjusted according to a size of thecavity 119. Thecavity 119 may be used as a storage space for electronic devices, in addition to receiving thestopper 160, so as to improve space utilization.

The capacitivepressure sensing device 100 further includes a capacitance detection circuit (not shown) electrically connected to the first and secondcapacitive plates 120, 130. The capacitance detection circuit is configured to detect a capacitance of a capacitor formed by thefirst capacitor plate 120 and thesecond capacitor plate 130, and output a detection result. In this embodiment, the capacitance detection circuit may be accommodated in thecavity 119 and electrically connected to thefirst capacitor plate 120 and thesecond capacitor plate 130 through a connection line.

Referring to fig. 10, anelectronic device 200 is further provided in the present embodiment, where theelectronic device 200 may be any electronic device with a touch function. For example, theelectronic device 200 may be a smartphone, a tablet, a wearable device, an e-reader, an in-vehicle device, and so on.

Theelectronic device 200 includes ahousing 210 and the capacitivepressure sensing device 100, wherein the capacitivepressure sensing device 100 is disposed on thehousing 210 for sensing a pressing force acting on thehousing 210.

When thehousing 210 is in a closed shape and is adapted to theelastic carrier 110, the inner wall of thehousing 210 can be attached to theelastic carrier 110, and theelastic carrier 110 can deform due to the pressing at any position on the outer peripheral surface of thehousing 210, and the elastic carrier is sensed by the capacitivepressure sensing device 100. For the conventional pressure sensor described in the background art, a plurality of pressure sensors need to be arranged on thehousing 210 to be able to sense the pressing at any position of the outer peripheral surface, and the capacitivepressure sensing device 100 can be implemented by only one pressure sensor, so that the structure is simpler and the installation is more convenient. Illustratively, thehousing 210 may have a cylindrical structure, theelastic carrier 110 may have a spiral structure, and the inner diameter of thehousing 210 is substantially equal to the outer diameter of theelastic carrier 110.

Of course, thehousing 210 may also have other structures, such as a rectangular parallelepiped structure commonly used for a smart phone, a tablet computer, and the like. At this time, theelastic carrier 110 may partially fit thehousing 210, and the pressing on thehousing 210 can also cause theelastic carrier 110 to deform, so as to be sensed by the capacitivepressure sensing apparatus 100. Theelectronic device 200 may include a plurality of capacitivepressure sensing devices 100, and the plurality of capacitivepressure sensing devices 100 may be uniformly arranged within thehousing 210 to improve pressure detection sensitivity.

Theelectronic device 200 may further comprise a control circuit electrically connected to the capacitance detection circuit for detecting a capacitance value between the first andsecond capacitor plates 120, 130 and transmitting to the control circuit. The control circuit can also store a capacitance threshold value which is used for judging whether the capacitance value detected by the capacitance detection circuit is larger than the capacitance threshold value; if the pressure exceeds the preset pressure, theshell 210 is judged to be pressed, and then the response action corresponding to the pressing operation is controlled to be executed, so that the mistaken touch is avoided.

For detailed structural features of the capacitivepressure sensing apparatus 100, refer to the related description of the above embodiments. Since theelectronic device 200 includes the capacitivepressure sensing apparatus 100 in the above embodiments, all the advantages of the capacitivepressure sensing apparatus 100 are provided, and are not described herein again.

Although the present application has been described with reference to a preferred embodiment, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the invention as defined by the appended claims.

Claims (12)

1. A capacitive pressure sensing device, comprising:

the elastic carrier is in a closed shape and comprises a first end face and a second end face which are respectively positioned at two ends of the elastic carrier, and the first end face and the second end face are staggered with each other;

the first capacitor polar plate is arranged on the elastic carrier along the direction from the first end face to the second end face;

the second capacitor plate is arranged on the elastic carrier along the direction from the second end face to the first end face, and the overlapping area of the first capacitor plate and the second capacitor plate in the radial direction of the elastic carrier changes along with the deformation of the elastic carrier.

2. The capacitive pressure sensing device of claim 1, wherein the elastic carrier is foldable under pressure and drives the first end surface and the second end surface to move in opposite directions, and the overlapping area of the first capacitive plate and the second capacitive plate in the radial direction of the elastic carrier is positively correlated to the pressure applied to the elastic carrier.

3. The capacitive pressure sensing device of claim 1, wherein the resilient carrier includes a first layer and a second layer spaced apart from each other in a radial direction of the resilient carrier, the first layer including the first end face, the second layer including the second end face, the first capacitive plate disposed in the first layer, the second capacitive plate disposed in the second layer.

4. A capacitive pressure sensing device according to claim 3, wherein the first layer and the second layer at least partially coincide in a radial direction of the elastic carrier when the elastic carrier is not under compression.

5. The capacitive pressure sensing device of claim 3, wherein said first layer includes a first surface and said second layer includes a second surface, said first surface and said second surface being on a same side of said elastomeric carrier, said first capacitive plate being attached to said first surface and said second capacitive plate being attached to said second surface, said elastomeric carrier being formed from an elastomeric dielectric material.

6. The capacitive pressure sensing device of claim 3, wherein the first layer comprises a first surface and the second layer comprises a second surface, the first surface and the second surface being on opposite sides of the elastomeric carrier; the first capacitor plate is attached to the first surface, the second capacitor plate is attached to the second surface, and a dielectric layer is arranged between the first capacitor plate and the second capacitor plate.

7. The capacitive pressure sensing device of claim 1, wherein the elastic carrier is an elastic ribbon, the elastic carrier being a spiral structure formed by the elastic ribbon being rolled.

8. The capacitive pressure sensing device according to claim 1, further comprising a pressing portion that abuts the elastic carrier.

9. The capacitive pressure sensing device according to claim 8, wherein the pressing portion comprises a pressing plate and a supporting plate which are oppositely arranged, and the elastic carrier is abutted between the pressing plate and the supporting plate.

10. The capacitive pressure sensing device according to claim 1, wherein the elastic carrier has a cavity, and the capacitive pressure sensing device further comprises a stopper disposed in the cavity, the stopper being capable of abutting against the elastic carrier when the elastic carrier is deformed.

11. The capacitive pressure sensing device of any one of claims 1-10, further comprising a capacitance detection circuit electrically connected to the first and second capacitive plates.

12. An electronic device comprising a housing and the capacitive pressure sensing device of any one of claims 1-11, the capacitive pressure sensing device disposed on the housing.

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