Invisible, contactless switch device

• US 10,193,550 B2
• Filed: 01/07/2015
• Issued: 01/29/2019
• Est. Priority Date: 01/09/2014
• Status: Active Grant

• Current Assignee: Roberto Airoldi
• Original Assignee: Roberto Airoldi
• Inventors: Airoldi, Roberto
• Primary Examiner(s): Fleming, Fritz M
• Assistant Examiner(s): Dhillon, Jagdeep
• Application Number:
  US15/109,909
• Publication Number:
  US 20160329893A1
• Time in Patent Office: 1,483 Days
• Field of Search: 307125, 307 66, 307 64, 307 82, 320107, 320108, 363 2112, 363 2114, 324663, 324664, 324686, 343702, 341 33
• CPC Class Codes: G01R 27/26 Measuring inductance or capacitance; Measuring quality factor, e.g. by using the resonance method; Measuring loss factor; Measuring dielectric constants ; Measuring impedance or related variables
• CPC Class Codes: H01Q 1/38 formed by a conductive layer on an insulating support patch antennas H01Q9/0407; microstrip dipole antennas H01Q9/065; microstrip slot antennas H01Q13/106; transmission line microstrip antennas H01Q13/206; manufacturing reflecting surfaces using insulating material for supporting the reflecting surface H01Q15/142
• CPC Class Codes: H03K 17/94 characterised by the way in which the control signals are generated
• CPC Class Codes: H03K 17/955 using a capacitive detector
• CPC Class Codes: H03K 2217/94089 Wireless transmission
• CPC Class Codes: H03K 2217/960765 Details of shielding arrangements

Abstract

A switching device adapted to be installed behind an opaque wall (32) so as not to be visible from the outside of the wall and intended to switch at least one electrical device (44) on. This switching device includes a first module (10) and a second module (12) adapted to make the connection between the device and a power source. The first module includes a capacitive sensor (16) having a capacitor on a printed circuit board adapted to change its capacitance value when the hand (34) of a user on the outside is placed near the wall where the device is installed. The capacitor is included in a metal frame whose function is to define the capacitive field due to the capacitor in the plane of the board and to maximize this field perpendicular to the plane of the board.

Claims

1. A switching device adapted to be installed behind an opaque wall so as not to be visible from the outside of said wall and intended to switch at least one electrical device on and comprising at least a first module connected by a wireless link or a wired link to a second module adapted to make the connection between said electrical device and a power source, said first module comprising a capacitive sensor adapted to change its capacitance value when the hand or any other part of the body of a user on the outside is placed near the wall where said switching device is installed,

said switching device being characterized in that the capacitive sensor, which is located on a printed circuit board comprises a capacitor C_x having a first metal electrode consisting of a solid circle and a second metal electrode surrounding said first electrode and being concentric with it, both electrodes being included in a metal frame, whose function is to define the capacitive field resulting from the capacitor formed by the two electrodes in the plane of the board and to maximize this field perpendicular to the plane of the board,

wherein said capacitive sensor contains a circuit for calculating the number of times N_r a reference voltage V_r must be applied to said capacitor C_x so that it can charge a reference capacitor C_r to a predetermined value, and

wherein said first module comprises a first microcontroller adapted to transmit instructions to a second microcontroller in said second module intended to control the connection of said electrical device to its electrical power source when said reference number N_r has been reduced due to a parasitic capacitor C_c caused by the approach of the hand of the user is added in parallel to said reference capacitor C_r.

2. The device according to claim 1, wherein said capacitor C_x has a capacitance value between 10 pF and 25 pF.

3. The device according to claim 2, wherein said capacitor C_r has a capacitance value of approximately 35 nF.

4. The device according to claim 1, wherein said capacitor C_r has a capacitance value of approximately 0.3 pF.

5. The device according to claim 1, wherein said wireless link is between a radio transmitter in said first module and a radio receiver in said second module.

6. The device according to claim 1, comprising a plurality of modules identical to said first module each having a capacitive sensor, which communicate with a second module through a wireless link or a wired link, said second module being adapted to switch at least one electrical device on or off by means of switches controlled by a second microcontroller.

7. The device according to claim 6, wherein said plurality of modules is used as a light dimmer by passing the hand in an upward motion in front of said wall so as to activate at least two capacitive sensors to increase the light intensity, and in a downward motion to decrease the light intensity.

8. The device according to claim 1, wherein said wall is made of metal.

9. The device according to claim 8, wherein said metal is copper.