Capacitive microswitch
By monitoring changes in capacitance value using a capacitor microswitch structure, the problem of insufficient response speed and flexibility of existing microswitches is solved, achieving faster response and more flexible switching control.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- 河南皓泽电子股份有限公司昆山分公司
- Filing Date
- 2025-08-05
- Publication Date
- 2026-07-21
AI Technical Summary
Existing microswitches lack a structure that uses a capacitor to trigger, resulting in insufficient response speed and flexibility.
A capacitor microswitch structure is adopted, which determines the open and closed state of the switch by monitoring the change in capacitance between the transmitting and receiving plates. The change in capacitance is detected by a capacitance detection chip to control the switch.
It enables control of the switching state through changes in capacitance, improving response speed and flexibility, and is suitable for various electronic products.
Smart Images
Figure CN224538180U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the field of electronic product technology, and specifically relates to a capacitive micro switch. Background Technology
[0002] Microswitches are widely used in various electronic products such as electrical appliances, machinery, communications, digital audio-visual equipment, and building automation due to their advantages such as compact structure, flexible operation, and fast response speed.
[0003] Existing microswitches typically employ a mechanical force-triggered circuit switching principle, lacking existing structures that utilize capacitors for triggering. Utility Model Content
[0004] The present invention addresses the aforementioned technical problems by providing a capacitive micro switch.
[0005] A capacitive micro switch includes a base and a housing, the base and the housing being connected to form a hollow cavity, and the following is disposed within the hollow cavity:
[0006] A spring sheet, the spring sheet being horizontally arranged, one end of the spring sheet being a fixed end and the other end being a free end, the fixed end being fixed in the hollow cavity, the spring sheet having a pressure-applying end, the pressure-applying end being located between the fixed end and the free end;
[0007] The emitter plate has its bottom end serving as a power-on pin connected to an external circuit for power supply, and its top end connected to the spring contact, which serves as an extension of the emitter plate.
[0008] The first receiving plate has its bottom end connected to an external circuit as a power-on pin. The first receiving plate is located below the free end, and a first capacitor structure is formed between the first receiving plate and the free end.
[0009] When a downward force is applied to the pressure end, the spring is moved downward, and the free end moves closer to the first receiving plate, which reduces the distance between the two plates of the first capacitor structure and increases the capacitance value of the first capacitor structure. The activation state of the capacitor micro switch is determined by monitoring the capacitance value of the first capacitor structure.
[0010] Optionally, one of the base and the housing is provided with a snap-fit hole and the other is provided with a snap-fit protrusion, and the snap-fit connection between the base and the housing is achieved by snapping the snap-fit hole with the snap-fit protrusion.
[0011] Optionally, both the transmitting electrode and the first receiving electrode are embedded in the base, with the top surface of the first receiving electrode extending out of the top surface of the base and located below the free end.
[0012] Optionally, a support plate is integrally formed at the top of the emitting electrode plate, and a support groove is provided on the support plate, with the fixed end of the spring piece embedded in the support groove.
[0013] Optionally, an abutment plate is integrally formed on the top of the emitting electrode, and an abutment groove is provided on one side of the abutment plate;
[0014] The spring sheet has a relief groove in the middle, and an arc-shaped elastic plate is provided in the relief groove. One end of the elastic plate is integrally connected to the spring sheet, and the other end of the elastic plate abuts in the abutment groove, so that the free end of the spring sheet has a preset distance from the first receiving electrode plate in the normal state.
[0015] Optionally, the hollow cavity may further include:
[0016] A fixed baffle is located above the free end. Under normal conditions, the fixed baffle is in contact with the free end or has a preset distance from the free end.
[0017] Optionally, the fixing baffle is integrally formed with the base and located at the top of the base.
[0018] Optionally, the hollow cavity may further include:
[0019] The second receiving plate has its bottom end connected to an external circuit as a power-on pin. The second receiving plate is located above the free end, and a second capacitor structure is formed between the second receiving plate and the free end.
[0020] When a downward force is applied to the pressure end, the spring is moved downward, and the free end moves closer to the first receiving plate, which reduces the distance between the two plates of the first capacitor structure and increases the capacitance value of the first capacitor structure. At the same time, the free end moves away from the second receiving plate, which increases the distance between the two plates of the second capacitor structure and decreases the capacitance value of the second capacitor structure. The activation state of the capacitor micro switch is determined by monitoring the capacitance values of the first capacitor structure and the second capacitor structure.
[0021] Optionally, when a fixed baffle is provided above the free end, the second receiving electrode is embedded at the bottom end of the fixed baffle.
[0022] Optionally, the outer periphery of the first receiving electrode plate and the second receiving electrode plate has an adhesive layer.
[0023] Optionally, the free end has an upper spring end and a lower spring end arranged side by side, causing the free end to form a double-layer spring end structure. The lower spring end forms the first capacitor structure with the first receiving electrode plate, and the upper spring end forms the second capacitor structure with the second receiving electrode plate.
[0024] Beneficial effects: This utility model monitors the change in capacitance value between the transmitting and receiving plates by changing the distance between the plates, and uses this change in capacitance value to determine the pressure applied at the spring end, thereby achieving the purpose of controlling the opening and closing state of the capacitor micro switch through the capacitor structure. Attached Figure Description
[0025] Figure 1 This is a schematic diagram of a structure according to Embodiment 1 of the present utility model;
[0026] Figure 2 for Figure 1 Exploded view;
[0027] Figure 3 for Figure 1 Partial structural diagram;
[0028] Figure 4 for Figure 3 Another perspective illustration;
[0029] Figure 5 for Figure 3 Internal structure diagram;
[0030] Figure 6 This is an exploded view of Embodiment 2 of the present invention;
[0031] Figure 7 for Figure 6 A partial internal structure diagram;
[0032] Figure 8 for Figure 7 Exploded view;
[0033] Figure 9 This is an exploded view of embodiment 3 of the present invention;
[0034] Figure 10 for Figure 9 A partial internal structure diagram;
[0035] Figure 11 for Figure 10 Exploded view. Detailed Implementation
[0036] The preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings, so as to better understand the purpose, features and advantages of the present invention. It should be understood that the embodiments shown in the drawings are not intended to limit the scope of the present invention, but are only for illustrating the essential spirit of the technical solution of the present invention.
[0037] In the following description, certain specific details are set forth for the purpose of illustrating various disclosed embodiments in order to provide a thorough understanding of the various disclosed embodiments. However, those skilled in the art will recognize that embodiments may be practiced without one or more of these specific details. In other instances, well-known apparatuses, structures, and techniques associated with this application may not have been shown or described in detail to avoid unnecessarily obscuring the description of the embodiments.
[0038] Throughout this specification, references to "an embodiment" or "an embodiment" indicate that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment. Therefore, the appearance of "in an embodiment" or "an embodiment" in various places throughout the specification does not necessarily refer to the same embodiment. Furthermore, a particular feature, structure, or characteristic may be combined in any manner in one or more embodiments.
[0039] In the following description, in order to clearly demonstrate the structure and working method of this utility model, a number of directional terms will be used. However, terms such as "front", "back", "left", "right", "outside", "inside", "outward", "inward", "up", and "down" should be understood as convenient terms and not as limiting terms.
[0040] Example 1:
[0041] Reference Figures 1 to 5 This embodiment provides a capacitive micro switch to control the opening and closing states of pressure-applying components such as buttons or switches through a capacitor structure. The capacitive micro switch of this embodiment includes a base 10, a housing 20, a spring contact 30, and a capacitor structure assembly, which includes a transmitting electrode 50, a first receiving electrode 60, and a second receiving electrode 70.
[0042] The base 10 and the outer shell 20 are connected to form a hollow cavity, and the spring 30, the transmitting electrode 50, the first receiving electrode 60 and the second receiving electrode 70 are all disposed in the hollow cavity.
[0043] The spring piece 30 is horizontally positioned within the hollow cavity, meaning its length is horizontal, and it possesses elastic deformation and repositioning capabilities in the vertical direction (up and down). One end of the spring piece 30 is a fixed end 30a, and the other end is a free end 30b. The fixed end 30a is fixed within the hollow cavity, meaning it remains stationary, while the free end 30b can elastically deform and reposition. The spring piece 30 also has a pressure-applying end located between the fixed end 30a and the free end 30b. A pressure-applying component, such as a button 40, can apply a downward force or release the pressure-applying end; alternatively, other pressure-applying components can also be used to achieve this.
[0044] When the pressure-applying component is a button 40, the button 40 is confined within the hollow cavity, with its top protruding from the outer casing 20 to allow for external downward pressing force. The bottom end of the button 40 abuts against the pressing end of the spring 30. When downward pressing force is applied to the top of the button 40, it causes the spring 30 to move downward. One fixed end 30a of the spring 30 remains stationary, while the free end 30b moves downward. When the pressing force is removed, the free end 30b and the button 40 return to their initial positions under the reset action of the spring 30.
[0045] Of course, the pressure-applying component can also be other devices located below the pressure-applying end. In this case, the pressure-applying component applies a downward pulling force to the pressure-applying end, causing the spring 30 to move downward. One end of the spring 30, the fixed end 30a, remains stationary, while the free end 30b moves downward. When the pulling force is removed, the free end 30b returns to its initial position under the reset action of the spring 30.
[0046] The bottom end of the emitting plate 50 serves as a power-on pin, connecting to an external circuit for power supply. In specific implementations, the bottom end of the power-on pin extends outside the hollow cavity to facilitate connection with the external circuit. The top end of the emitting plate 50 is connected to the spring 30, making the spring 30 an extension of the emitting plate 50. In this case, the spring is a metal structure spring, so that after power is applied, it can form a first capacitor structure with the first receiving plate 60 and a second capacitor structure with the second receiving plate 70.
[0047] The bottom end of the first receiving plate 60 serves as a power-on pin, connecting to an external circuit for power supply. Similarly, in a specific implementation, the bottom end of the power-on pin of the first receiving plate 60 extends outside the hollow cavity to facilitate connection with an external circuit. The first receiving plate 60 is located below the free end 30b, forming a first capacitor structure between the first receiving plate 60 and the free end 30b. Since the spring 30 is horizontally positioned, the end face of its free end 30b is a horizontal plane, and the plate surface of the first receiving plate 60 is also a horizontal plane, so that the plate surface of the first receiving plate 60 and the end face of the free end 30b are horizontally opposite each other to form the first capacitor structure.
[0048] The bottom end of the second receiving plate 70 serves as a power-on pin, connecting to an external circuit for power supply. Similarly, in a specific implementation, the bottom end of the power-on pin of the second receiving plate 70 extends outside the hollow cavity to facilitate connection with an external circuit. The second receiving plate 70 is located above the free end 30b, forming a second capacitor structure between the second receiving plate 70 and the free end 30b. The surface of the second receiving plate 70 is also horizontal, so that the surface of the second receiving plate 70 and the end face of the free end 30b are horizontally opposite each other to form a first capacitor structure.
[0049] When a downward force is applied to the pressure end, the spring 30 moves downward, and the free end 30b moves closer to the first receiving plate 60, which reduces the distance between the two plates of the first capacitor structure and increases the capacitance value of the first capacitor structure. At the same time, the free end 30b moves away from the second receiving plate 70, which increases the distance between the two plates of the second capacitor structure and decreases the capacitance value of the second capacitor structure. The activation state of the capacitor micro switch is determined by monitoring the capacitance values of the first capacitor structure and the second capacitor structure.
[0050] The working principle of this embodiment is as follows:
[0051] A capacitor structure is formed by setting up an energized transmitting plate and a corresponding energized receiving plate. The opening and closing state of the capacitor microswitch is determined by changing the capacitance value of the capacitor structure.
[0052] The specific operation is as follows: The capacitance value of the capacitor structure is monitored by a capacitance detection chip. This chip can be a directly adopted capacitor detection chip used in existing technology for detecting the capacitance value between two electrode plates. When the capacitance value of the capacitor structure increases to a set threshold, the capacitance detection chip determines that the capacitor microswitch is in the activated state. It sends a switch activation signal to the device using the microswitch. After receiving the switch activation signal, the device using the microswitch connects its own circuit, causing the device to become activated. The principle is similar when turning it off. When used on a computer host or mouse, it can also be automatically turned off by the computer system or by default after a period of inactivity.
[0053] The factors that alter the capacitor structure include the facing area between the emitter and receiver plates, the distance between the emitter and receiver plates, and the dielectric constant between the emitter and receiver plates (i.e., the conductivity of the material between the emitter and receiver plates). The specific calculation formulas are as follows:
[0054]
[0055] Where C represents the capacitance, ε represents the dielectric constant between the two plates, S represents the effective area of the two plates facing each other, D represents the distance between the two plates, and K represents the electrostatic constant (approximately 8.99 x 10⁹ N·m). 2 / C 2 )
[0056] As can be seen from the above formula, the larger the effective area facing the capacitor, the larger the capacitance value of the capacitor structure; the smaller the distance between the two plates, the larger the capacitance value of the capacitor structure; and the larger the dielectric constant, the larger the capacitance value of the capacitor structure.
[0057] If other parameters remain constant, a change in the distance between the two plates will alter the capacitance value of the capacitor structure. In this embodiment, the capacitance detection chip is connected to the emitting plate 50, the first receiving plate 60, and the second receiving plate 70. The capacitance detection chip detects the first capacitance value between the emitting plate 50 and the first receiving plate 60, and the second capacitance value between the emitting plate 50 and the second receiving plate 70. When the distance between the emitting plate 50 and the first receiving plate 60 or the second receiving plate 70 changes, the capacitance value of the first capacitor structure or the capacitance value of the second capacitor structure also changes. When the first capacitance value increases to a first set threshold, the capacitor microswitch is considered to be in the activated state. To avoid misjudgment, the detection accuracy is improved by detecting the second capacitance value; that is, the capacitor microswitch is only considered to be in the activated state when the second capacitance value decreases to a second set threshold. When the first capacitance value returns to the first initial threshold, the capacitor microswitch is considered to be in the closed state. Similarly, to avoid misjudgment, the capacitor microswitch is only considered to be in the closed state when the second capacitance value returns to the second initial threshold.
[0058] The aforementioned first set threshold, second set threshold, first initial threshold, and second initial threshold can be a set value or a set threshold range.
[0059] In one embodiment, one of the base 10 and the outer shell 20 is provided with a snap-fit hole and the other is provided with a snap-fit protrusion. The snap-fit connection between the base 10 and the outer shell 20 is achieved by snapping the snap-fit hole with the snap-fit protrusion.
[0060] Reference Figure 2 The buckle protrusions 11 at both ends of the base 10 engage with the buckle holes 21 at both ends of the outer shell 20 to connect the base 10 and the outer shell 20.
[0061] In one embodiment, reference is made to Figure 2 The outer casing 20 is provided with a pressure hole 22 that is connected vertically, and the pressure-applying component, such as the top of the button 40, extends out from the pressure hole 22.
[0062] In one embodiment, both the transmitting electrode 50 and the first receiving electrode 60 are embedded in the base 10, and the top surface of the first receiving electrode 60 extends out of the top surface of the base 10 and is located below the free end 30b.
[0063] In one embodiment, reference is made to Figures 2 to 5 A support plate 51 is integrally formed at the top of the emitting electrode plate 50, and a support groove 52 is provided on the support plate 51. The fixed end 30a of the spring piece 30 is embedded in the support groove 52. The design of the support plate 51 can both fix the fixed end 30a and ensure that the spring piece 30 and the emitting electrode plate 50 remain connected.
[0064] In one embodiment, reference is made to Figures 2 to 5 The top of the emitting electrode plate 50 is integrally formed with an abutment plate 53, and an abutment groove 54 is provided on one side of the abutment plate 53.
[0065] A clearance groove is provided in the middle of the spring piece 30, and an arc-shaped elastic plate 31 is provided in the clearance groove. One end of the elastic plate 31 is integrally connected to the spring piece 30, and the other end of the elastic plate 31 abuts in the abutment groove 54, so that the free end 30b of the spring piece 30 has a preset distance from the first receiving electrode plate 60 in the normal state.
[0066] In practice, a U-shaped cut can be made in the middle of the spring piece 30 to cut out an avoidance groove and an elastic plate 31 integrally connected with the spring piece 30. Then, the elastic plate 31 is bent downward and the other end abuts against the abutment groove 54. That is to say, the abutment groove 54 is preferably located inside or below the avoidance groove.
[0067] The design of the abutment plate 53 also ensures that the spring 30 and the launching plate 50 remain connected.
[0068] When a downward force is applied to the pressing end of the spring 30, the free end of the spring 30 will move closer to the first receiving plate 60, and the elastic plate 31 will be squeezed. After the downward force is removed, under the elastic action of the elastic plate 31, the free end of the spring 30 returns to its original position and waits for the next pressing operation.
[0069] In one embodiment, the spring sheet 30 between the fixed end 30a and the free end 30b has an abutment surface, which serves as a pressure-applying end for contacting a pressure-applying component. In addition to the abutment surface, one or more vertically connected spring sheet slots may be provided on the spring sheet 30 between the fixed end 30a and the free end 30b to increase the elastic deformation capability of the spring sheet 30.
[0070] Of course, the clearance groove also serves as one of the spring clip through grooves.
[0071] In one embodiment, reference is made to Figures 2 to 5The capacitive micro switch also includes a fixed baffle 80, which is located within the hollow cavity and above the free end 30b. A second receiving electrode 70 is embedded at the bottom of the fixed baffle 80. Preferably, the second receiving electrode 70 is exposed at the bottom of the fixed baffle 80. A clearance opening can be provided at the bottom of the fixed baffle 80, through which the second receiving electrode 70 is open at the bottom of the fixed baffle 80.
[0072] Under normal conditions, the fixed baffle 80 abuts against the free end 30b. This normal condition is the initial state when no downward force is applied to the pressure end, or the reset state after reset. In this embodiment, the fixed baffle 80 provides an installation medium for the second receiving electrode 70 and also limits the initial position or reset position of the spring piece 30 after reset.
[0073] In one embodiment, the fixed baffle 80 is integrally formed with the base 10 and is located at the top of the base 10.
[0074] In one embodiment, the outer periphery of the first receiving electrode 60 and the second receiving electrode 70 has an adhesive layer.
[0075] In a capacitor structure, direct contact between the transmitting and receiving plates must be avoided, as this would prevent the formation of a capacitor. Therefore, direct contact between the free end 30b of the spring 30 and the first receiving plate 60 and the second receiving plate 70 must be avoided. This embodiment avoids this direct contact problem by providing an adhesive layer around both the first and second receiving plates.
[0076] In the capacitor structure of Embodiment 1 above, the positions of the emitting plate and the receiving plate can be interchanged without affecting the formation of the capacitor structure.
[0077] Example 2:
[0078] Reference Figures 6 to 8 This embodiment provides a capacitive micro switch, which is the same as that in embodiment 1 except for the following differences, and will not be described again here.
[0079] This embodiment omits the second receiving electrode 70, instead forming a first capacitor structure between the transmitting electrode 50 and the first receiving electrode 60. The activation state of the capacitive microswitch is determined through this first capacitor structure. This embodiment is simpler in structure as it lacks a receiving electrode.
[0080] In this embodiment, if a fixed baffle 80 is provided, the fixed baffle 80 directly limits the initial position or the reset position of the spring piece 30 after reset.
[0081] Example 3:
[0082] Reference Figures 9 to 11This embodiment provides a capacitive micro switch, which is the same as that in embodiment 1 except for the following differences, and will not be described again here.
[0083] The structure of the free end 30b in this embodiment differs from that in Embodiment 1, specifically:
[0084] The free end 30b has an upper spring end 32 and a lower spring end 33 arranged side by side, which causes the free end 30b to form a double-layer spring structure. The lower spring end 33 forms a first capacitor structure with the first receiving electrode 60, and the upper spring end 32 forms a second capacitor structure with the second receiving electrode 70.
[0085] Under normal conditions, the upper spring end 32 does not need to contact the bottom end of the second receiving electrode 70. When the fixed baffle 80 is provided in this embodiment, there is a preset distance between the upper spring end 32 and the fixed baffle 80.
[0086] In some embodiments, one end of the upper spring sheet 32 is integrally connected to one end of the lower spring sheet 33 and is integrally connected to the spring sheet 30.
[0087] The preferred embodiments of this utility model have been described in detail above. However, it should be understood that after reading the above teachings, those skilled in the art can make various alterations or modifications to this utility model. These equivalent forms also fall within the scope defined by the appended claims.
Claims
1. A capacitive micro switch, characterized in that, The system includes a base and a housing, which are connected to form a hollow cavity. Within the hollow cavity, the following components are disposed: A spring sheet, the spring sheet being horizontally arranged, one end of the spring sheet being a fixed end and the other end being a free end, the fixed end being fixed in the hollow cavity, the spring sheet having a pressure-applying end, the pressure-applying end being located between the fixed end and the free end; The emitter plate has its bottom end serving as a power-on pin connected to an external circuit for power supply, and its top end connected to the spring contact, which serves as an extension of the emitter plate. The first receiving plate has its bottom end connected to an external circuit as a power-on pin. The first receiving plate is located below the free end, and a first capacitor structure is formed between the first receiving plate and the free end.
2. The capacitive micro switch as described in claim 1, characterized in that, One of the base and the outer shell is provided with a snap-fit hole and the other is provided with a snap-fit protrusion. The snap-fit connection between the base and the outer shell is achieved by snapping the snap-fit hole with the snap-fit protrusion.
3. The capacitive micro switch as described in claim 1, characterized in that, Both the transmitting electrode and the first receiving electrode are embedded in the base, and the top surface of the first receiving electrode extends out of the top surface of the base and is located below the free end.
4. The capacitive micro switch as described in claim 1, characterized in that, The top of the emitting electrode plate is integrally formed with a support plate, and the support plate is provided with a support groove, and the fixed end of the spring is embedded in the support groove.
5. The capacitive micro switch as described in claim 1, characterized in that, The top of the emitting electrode is integrally formed with an abutment plate, and an abutment groove is provided on one side of the abutment plate; The spring sheet has a relief groove in the middle, and an arc-shaped elastic plate is provided in the relief groove. One end of the elastic plate is integrally connected to the spring sheet, and the other end of the elastic plate abuts in the abutment groove, so that the free end of the spring sheet has a preset distance from the first receiving electrode plate in the normal state.
6. The capacitive micro switch as described in claim 1, characterized in that, The hollow cavity is also provided with: A fixed baffle is located above the free end. Under normal conditions, the fixed baffle abuts against the free end or has a preset distance from the free end. The fixed baffle is integrally formed with the base and is located at the top of the base.
7. The capacitive micro switch as described in any one of claims 1 to 6, characterized in that, The hollow cavity is also provided with: The second receiving plate has its bottom end connected to an external circuit as a power-on pin. The second receiving plate is located above the free end, and a second capacitor structure is formed between the second receiving plate and the free end.
8. The capacitive micro switch as described in claim 7, characterized in that, When a fixed baffle is provided above the free end, the second receiving electrode plate is embedded at the bottom end of the fixed baffle.
9. The capacitive micro switch as described in claim 7, characterized in that, The first receiving electrode and the second receiving electrode have an adhesive coating layer on their outer periphery.
10. The capacitive micro switch as described in claim 7, characterized in that, The free end has an upper spring end and a lower spring end arranged side by side, which causes the free end to form a double-layer spring end structure. The lower spring end and the first receiving plate form the first capacitor structure, and the upper spring end and the second receiving plate form the second capacitor structure.