RU2678775C2 - Proximity switch assembly (versions) - Google Patents

Abstract

FIELD: electricity.SUBSTANCE: invention relates to a proximity switch assembly and to a method for detecting the activation of a proximity switch assembly. Assembly includes a plurality of proximity switches, each having a proximity sensor providing an excitation field for determining and a control circuit that processes the excitation field of each proximity switch for determining activation. Malleable material covers the proximity sensors. Recess is formed in a substrate between the malleable material and the sensor. Groove may extend in the substrate between adjacent proximity switches. Malleable material may further include a protruding portion.EFFECT: improved detection of switch activation.20 cl, 38 dwg

Description

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a partial continuation of the application for the grant of a US patent No. 14/284,659, filed on May 22, 2014 and entitled "MILITARY CONTACTLESS SWITCHING UNIT AND METHOD OF ACTIVATION" ("PLIABLE PROXIMITY SWITCH ASSEMBLY AND ACTIVATION", a continuation of the METHOD application) the grant of a US patent No. 14/168,614, filed on January 30, 2014, entitled "CONTACTLESS SWITCHING NODE AND ACTIVATION METHOD WITH A VIRTUAL BUTTON MODE" ("PROXIMITY SWITCH ASSEMBLY AND ACTIVATION METHODAL HANDLING) issuing US Patent No. 13 / 444,393, filed April 11, 2012, entitled “PROXIMITY SWITCH ASSEMBLY AND ACTIVATION METHOD WITH EXPLORATION MODE”. The above related applications are hereby incorporated by reference.

FIELD OF THE INVENTION

The present invention relates generally to switches, and in particular, relates to proximity switches having an improved determination of activation of a switch.

BACKGROUND

Automobile vehicles are typically equipped with various user-driven switches, such as switches for controlling devices, including power windows, headlights, wipers, transparent or translucent sunroofs, interior lighting, radio and infotainment devices, and various other devices. Typically, these types of switches need to be activated by the user in order to activate or deactivate the device or perform some type of control function. Proximity switches, such as capacitive switches, use one or more proximity sensors to generate an excitation field to detect and detect changes in the excitation field, indicating the actuation of the switch by the user, typically with the user's finger in close proximity or in contact with the sensor. Capacitive switches are typically configured to detect actuation of the switch by the user based on a comparison of the field of excitation for determination with a threshold value.

Switching nodes often employ multiple capacitive switches in close proximity to each other and typically require the user to select the single required capacitive switch to perform the intended operation. In some applications, such as in-car use, a vehicle driver has limited ability to see switches due to driver distraction. In such applications, it is desirable to provide the user with the opportunity to grope for a specific button in the switching node, in the meantime, avoiding prematurely determining the activation of the switch. Thus, it is desirable to distinguish whether the user intends to activate the switch or simply finds the specific button of the switch, meanwhile, focusing on a higher priority task, such as driving, or does not intend to activate the switch. Accordingly, it is desirable to provide a proximity switch device that improves the use of proximity switches by a person, such as a vehicle driver.

SUMMARY OF THE INVENTION

According to one aspect of the present invention, a contactless switching unit is provided, comprising:

a rigid substrate having upper and lower surfaces;

proximity sensor located on the substrate;

malleable material located on the upper surface of the substrate; and

a recess in the upper surface of the substrate in the region between the compliant material and the proximity sensor, the depression being larger than the proximity sensor.

In one embodiment, a node is proposed in which the recess has a first length and the proximity sensor has a second length, the first length being at least 5 millimeters longer than the second length.

In one of the options proposed site in which the first length exceeds the second length in the range from 5 to 10 millimeters.

In one of the options proposed site in which the recess has a thickness in the range from 0.5 to 2.0 millimeters.

In one embodiment, a knot is proposed in which pliable material is rubber.

In one of the options proposed site in which the air gap is formed in the recess.

In one embodiment, a node is proposed in which a proximity sensor is located on the lower surface of the substrate.

In one embodiment, a node is proposed that further comprises a control circuit that controls the excitation field associated with the proximity sensor and determines the activation of the proximity switch based on the signal generated by the sensor relative to the threshold value when the user's finger presses compliant material.

In one embodiment, an assembly is provided in which the assembly comprises a plurality of proximity switches, each of the proximity switches comprising a proximity sensor formed on a lower surface of the substrate, and a recess formed on the upper surface of the substrate, and at least one groove extending into the substrate between adjacent proximity switches.

In one embodiment, a node is provided comprising a capacitive switch comprising one or more capacitive sensors.

In one of the options proposed site installed in the vehicle.

In one embodiment, a node is proposed in which a malleable material comprises a protruding portion located above the recess.

According to another aspect of the present invention, a non-contact switching vehicle assembly is provided, comprising:

a rigid substrate having a first and second surface;

a proximity sensor located on the first surface of the substrate;

malleable material located on the second surface of the substrate; and

a recess forming an air gap in the second surface of the substrate in the region between the compliant material and the proximity sensor, the depression being longer than the proximity sensor.

In one embodiment, a node is proposed in which the recess has a first length and the proximity sensor has a second length, the first length being at least 5 millimeters longer than the second length.

In one of the options proposed site in which the first length exceeds the second length in the range from 5 to 10 millimeters.

In one of the options proposed site in which the recess has a thickness in the range from 0.5 to 2.0 millimeters.

In one embodiment, a knot is proposed in which pliable material is rubber.

In one embodiment, a node is provided in which the proximity switch comprises a capacitive switch comprising one or more capacitive sensors.

In one embodiment, a node is proposed in which a malleable material comprises a protruding portion located above the recess.

In one embodiment, a node is provided comprising a plurality of proximity switches, each of the proximity switches comprising a proximity sensor formed on a lower surface of the substrate, and a recess formed on the upper surface of the substrate, and at least one groove extending into the substrate between adjacent proximity switches.

These and other aspects, objects and features of the present invention will be understood and appreciated by those skilled in the art to study the following description of the invention, claims, and the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings:

FIG. 1 is a perspective view of a passenger compartment of an automobile vehicle having a console above a windshield using a contactless switching unit, according to one embodiment;

FIG. 2 is an enlarged view of the console above the windshield and the proximity switch assembly shown in FIG. one;

FIG. 3 is an enlarged cross-sectional view taken along line III-III of FIG. 2, showing an array of proximity switches relative to a user's finger;

FIG. 4 is a schematic illustration of a capacitive sensor used in each of the capacitive switches shown in FIG. 3;

FIG. 5 is a block diagram illustrating a contactless switching unit according to one embodiment;

FIG. 6 is a graph illustrating a signal count for one channel coupled to a capacitive sensor, showing an activation motion profile;

FIG. 7 is a graph illustrating a signal count for two channels associated with capacitive sensors, showing a profile of a sliding groping / searching motion;

FIG. 8 is a graph illustrating a signal count for a signal path associated with capacitive sensors, showing a profile of slow activation motion;

FIG. 9 is a graph illustrating a signal count for two channels associated with capacitive sensors, showing a profile of a fast-moving groping / searching motion;

FIG. 10 is a graph illustrating a signal count for three channels associated with capacitive sensors in a fumble / search mode, illustrating activation by stable pressing on a peak, according to one embodiment;

FIG. 11 is a graph illustrating a signal count for three channels associated with capacitive sensors in a groping / searching mode, illustrating activation by steadily clicking on a signal falling below a peak, according to another embodiment;

FIG. 12 is a graph illustrating a signal count for three channels associated with capacitive sensors in a fumble / search mode, illustrating an increased stable pressing on a pad to activate a switch, according to a further embodiment;

FIG. 13 is a graph illustrating a signal count for three channels associated with capacitive sensors in a fumble mode and site selection based on increased stable depression, according to a further embodiment;

FIG. 14 is a state graph illustrating five states of a capacitive switch assembly implemented by a state machine, according to one embodiment;

FIG. 15 is a flowchart illustrating a procedure for executing a method of activating a switch of a switching unit according to one embodiment;

FIG. 16 is a flowchart illustrating switch activation and switch release processing;

FIG. 17 is a flowchart illustrating logic for switching between undefined and active states of a switch;

FIG. 18 is a flowchart illustrating logic for switching from an active state of a switch to an undefined state of a switch or a threshold state of a switch;

FIG. 19 is a flowchart illustrating a procedure for switching between a threshold state of a switch and a search state of a switch;

FIG. 20 is a flowchart illustrating a virtual button method that implements a switch search state;

FIG. 21 is a graph illustrating a signal count for a channel associated with a capacitive sensor having a groping mode and a virtual button mode for activating a switch, according to a further embodiment;

FIG. 22 is a graph illustrating a signal count for a virtual button mode in which activation is not triggered;

FIG. 23 is a graph illustrating a signal count for a capacitive sensor in a fumble mode, further illustrating when a switch is activated, according to the embodiment of FIG. 21;

FIG. 24 is a graph illustrating a signal count for a capacitive sensor, further illustrating when activations are triggered, according to the embodiment of FIG. 21;

FIG. 25 is a graph illustrating a signal count for a capacitive sensor, further illustrating a timeout for exiting virtual button mode and re-entering virtual button mode, according to the embodiment of FIG. 21;

FIG. 26 is a flowchart illustrating a procedure for processing a signal path with a virtual button mode according to the embodiment shown in FIG. 21;

FIG. 27 is a flowchart illustrating a virtual button mode for processing a signal path according to the embodiment of FIG. 21;

FIG. 28A is a cross-sectional view of a contactless switching unit having proximity switches and covering pliable material with respect to a user's finger shown in a first position, according to another embodiment;

FIG. 28B is a cross-sectional view of the contactless switching assembly of FIG. 28A, further illustrating a user's finger in a second position;

FIG. 28C is a cross-sectional view of the contactless switching assembly of FIG. 28A, further illustrating finger pressing on the compliant layer in a third position;

FIG. 28D is a graph illustrating a signal generated by one of the proximity sensors in response to moving a finger and pressing a compliant cover, as seen in FIG. 28A-28C;

FIG. 29A is a cross-sectional view of a contactless switching assembly utilizing a compliant coating material having protruding regions with air gaps and a user's finger shown in a first position according to a further embodiment;

FIG. 29B is a cross-sectional view of the contactless switching assembly of FIG. 29A, further illustrating a user's finger in a second position;

FIG. 29C is a cross-sectional view of a contactless switching unit as seen in FIG. 29A, further illustrating the pressing of a switch by a user's finger in a third position;

FIG. 29D is a graph illustrating a signal generated by one of the sensors in response to a finger movement, as shown in FIG. 29A-29C;

FIG. 30 is a state graph illustrating various states of a capacitive switch assembly having a coating of compliant material and a virtual button mode;

FIG. 31 is a flowchart illustrating a procedure for processing a signal generated by a proximity switch coated with a compliant material according to one embodiment;

FIG. 32 is a perspective cross-sectional view of a console above a vehicle windshield having a non-contact switching assembly utilizing recesses in the substrate and a compliant coating, according to one embodiment;

FIG. 33 is a plan view of the console above the windshield and the switching assembly shown in FIG. 32 with sensors and recesses shown by invisible dashed lines;

FIG. 34A is a cross-sectional view of the contactless switching assembly shown in FIG. 32, and the finger of the user shown in the first position, according to one embodiment;

FIG. 34B is a cross-sectional view of the contactless switching assembly of FIG. 34A, further illustrating a user's finger in a second position;

FIG. 34C is a cross-sectional view of the contactless switching unit as seen in FIG. 34A, further illustrating the pressing of the switch by a user's finger in a third position;

FIG. 34D is a graph illustrating a signal generated by one of the proximity sensors in response to a finger movement, as shown in FIG. 34A-34C;

FIG. 35 is a cross-sectional perspective view of a console above a vehicle windshield having a contactless switching assembly utilizing a groove between adjacent sensors, according to yet another embodiment;

FIG. 36 is a plan view of the console above the windshield and the switching assembly shown in FIG. 35 with sensors, recesses, and grooves shown by invisible lines;

FIG. 37A is a cross-sectional view of the contactless switching assembly shown in FIG. 35 and a finger of a user shown in a first position according to another embodiment;

FIG. 37B is a cross-sectional view of the contactless switching assembly of FIG. 37A, further illustrating a user's finger in a second position;

FIG. 37C is a cross-sectional view of a contactless switching unit as seen in FIG. 37A, further illustrating a user's finger in a third position;

FIG. 37D is a cross-sectional view of a contactless switching unit as seen in FIG. 37A, further illustrating a user's finger in a fourth position;

FIG. 37E is a graph illustrating two signals generated by two sensors in response to a finger movement, as shown in FIG. 37A-37D; and

FIG. 38 is a cross-sectional view of a contactless switching assembly utilizing a compliant coating material having a recess and a protruding region in the compliant material above each recess, according to a further embodiment.

DESCRIPTION OF THE PREFERRED EMBODIMENTS OF THE INVENTION

As required, detailed embodiments of the present invention are disclosed herein; however, it should be understood that the disclosed embodiments are merely an example of the invention, which may be embodied in various and alternative forms. The figures are not necessarily intended for detailed design; some circuits may be exaggerated or minimized to show a general functional presentation. Therefore, the specific structural and functional details disclosed in the materials of the present description should not be interpreted as limiting, but only as representing the basis for studying by a person skilled in the art for various applications of the present invention.

With reference to FIG. 1 and 2, the interior of an automobile vehicle 10 having a passenger compartment and a switching unit 20 having a plurality of proximity switches 22 having monitoring and determining a switch activation according to one embodiment is generally illustrated. Vehicle 10 typically includes a console 12 above the windshield mounted on a headliner on the underside of the roof or ceiling in the upper part of the passenger compartment of the vehicle, generally above the front passenger landing area. The switching unit 20 has a plurality of proximity switches 22 located adjacent to each other in the console 12 above the windshield, according to one embodiment. Various proximity switches 22 can control any of a number of vehicle devices and functions, such as controlling the movement of a translucent or transparent sunroof 16, controlling the movement of the sunroof 18, managing activation of one or more lighting devices, such as interior lighting cards / readers and ceiling light 30, and various other devices and functions. However, it should be appreciated that the proximity switches 22 can be located anywhere in the vehicle 10, for example, on the dashboard, on other consoles, such as the center console, integrated in the touch screen display 14 for broadcasting or infotainment systems, such as a navigation and / or audio display, or are located anywhere on board a vehicle 10 according to various vehicle applications.

The proximity switches 22 are shown and described herein as capacitive switches according to one embodiment. Each proximity switch 22 includes at least one proximity sensor that provides an excitation field for determining to read a user's touch or proximity (for example, within one millimeter) to one or more proximity sensors, such as a finger-conducting movement of the user. Thus, the excitation field for detecting each proximity switch 22 is a capacitive field in an exemplary embodiment, and the user's finger has electrical conductivity and dielectric properties that cause a change or disturbance in the excitation field to determine how it should be apparent to those skilled in the art. However, it will also be appreciated by those skilled in the art that additional or alternative types of proximity sensors may be used, such as, but not limited to, inductive sensors, optical sensors, temperature sensors, resistance sensors, and the like, or a combination thereof . Exemplary proximity sensors are described in the ATMEL ^® Touch Sensor Design Guide dated April 9, 2009, 10620 D-AT42-04 / 09, which document is hereby incorporated by reference.

The proximity switches 22 shown in FIG. 1 and 2, each provides for controlling a component or device of a vehicle or provides an assigned control function. One or more of the proximity switches 22 may be allocated to control the movement of the translucent or transparent sunroof 16 to cause the transparent sunroof 16 to move in the opening or closing direction, to tilt the transparent sunroof or to stop the movement of the transparent sunroof based on an algorithm management. One or more other proximity switches 22 may be allocated to control the movement of the sunroof 18 of the transparent sunroof between the open and closed positions. Each of the transparent sunroof 16 and the shutter 16 can be driven by an electric motor in response to the actuation of the corresponding proximity switch 22. Other proximity switches 22 can be allocated to control other devices, such as turning on the internal light for illuminating the card / reading, turning it off lamp for illuminating the card / reading, turning the ceiling lamp on or off, unlocking the trunk, opening the tailgate or canceling the door light switch. Additional controls by proximity switches 22 may include actuating the raising and lowering of the door power windows. Various other vehicle controls may be controlled by proximity switches 22 described herein.

With reference to FIG. 3, a portion of a proximity switch assembly 20 is illustrated having an array of three consecutive proximity switches 22 in close connection with each other’s finger 34 during use of the switching assembly 20. Each proximity switch 22 includes one or more proximity sensors 24 to form an excitation field for determination. According to one embodiment, each of the proximity sensors 24 may be formed by printing conductive printing ink on the upper surface of the polymer console 12 above the windshield. One example of a non-contact ink sensor 24 is shown in FIG. 4, typically having a driving electrode 26 and a receiving electrode 28, each has opposing ridges to form a capacitive field 32. It should be noted that each of the proximity sensors 24 can be otherwise formed, for example, by mounting a preformed conductive trace circuitry according to other embodiments. The master electrode 26 receives the driving pulses of a square wave applied with a voltage V _I. The receiving electrode 28 has an output for generating an output voltage V _O. It will be appreciated that the electrodes 26 and 28 may be arranged in various other configurations to form a capacitive field as an excitation field 32.

In the embodiment shown and described herein, an input voltage signal V _{I is} applied to the driving electrode 26 of each proximity sensor 24 as square wave pulses having a charge pulse cycle sufficient to charge the receiving electrode 28 to the desired voltage. The receiving electrode 28, therefore, serves as a measuring electrode. In the shown embodiment, adjacent detection fields 32 for detection generated by adjacent proximity switches 22 are slightly overlapping, however, overlapping may not exist according to other embodiments. When the user or operator, for example, the user's finger 34 penetrates the field 32 of the excitation, the contactless switching unit 20 detects a disturbance caused by the finger 34 in relation to the field 32 of the excitation, and determines whether the disturbance is sufficient to activate the corresponding proximity switch 22. The perturbation of the field 32 excitation is detected by processing the signal of the pulse of charge associated with the corresponding channel of the signal. When the user's finger 34 is in contact with the two excitation fields 32, the contactless switching unit 20 detects a disturbance of the two excitation fields 32 contacted through the separate signal paths. Each proximity switch 22 has its own dedicated signal path, forming the counts of charge pulses, which is processed as discussed in the materials of the present description.

With reference to FIG. 5, a contactless switching unit 20 is illustrated according to one embodiment. A variety of proximity sensors 24 are shown that provide input to a controller 40, such as a microcontroller. The controller 40 may include a control circuit such as a microprocessor 42 and a memory 48. The control circuit may include a determination control circuit that processes the excitation field of each sensor 22 to determine if the user has activated the corresponding switch by comparing the excitation field signal with one or more threshold values in accordance with one or more management procedures. It will be appreciated that other analog and / or digital control circuits may be used to process each field of excitation, determine activation by the user, and initiate action. The controller 40 may employ a method QMatrix collect data available from ATMEL ^®, according to one embodiment. ATMEL uses a C / C ++ compiler and WinAVR debugger on the WINDOWS ^® host computer to simplify the development and testing of the Hawkeye utility, which provides real-time monitoring of the internal state of critical variables in the software, as well as collecting data logs for subsequent processing.

The controller 40 provides an output signal to one or more devices that are configured to perform special actions in response to the correct activation of the proximity switch. For example, one or more devices may include a transparent sunroof 16 having an electric motor for moving the transparent sunroof panel between open and closed and tilted positions, a transparent sunroof 18 that moves between the open and closed positions, and lighting devices 30 that can be turned on and off. Other devices, such as a radio, can be controlled to perform on and off functions, adjust the volume level, search for broadcast channels, and other types of devices to perform other special functions. One of the proximity switches 22 may be highlighted to cause the transparent sunroof to close, another proximity switch 22 may be highlighted to cause the transparent sunroof to open, and an additional switch 22 may be highlighted to bring the transparent sunroof into an inclined position, all of which would cause the electric motor to move the transparent sunroof to the desired position. The sunroof shutter 18 may open in response to one proximity switch 22 and may close in response to another proximity switch 22.

Additionally shown is a controller 40 having an analog-to-digital (A / D) comparison device 44 connected to the microprocessor 42. The comparison device 44 A / D receives the voltage output signal V _O from each of the proximity sensors 22, converts the analog signal to a digital signal, and outputs digital signal to microprocessor 42. Additionally, controller 40 includes a pulse counter 46 connected to microprocessor 42. Pulse counter 46 counts the pulses of the charge signal that are applied to each master electrode of each proximity sensor, it counts the pulses necessary to charge the capacitor until the voltage output signal V _O reaches a predetermined voltage, and issues a count to the microprocessor 42. The pulse count is an indication of the change in capacitance of the corresponding capacitive sensor. The controller 40 is additionally shown in communication with the pulse width modulation buffer 15. The controller 40 provides a pulse-width modulated signal to a pulse-width modulated driver 15 for generating a sequence of V _I square wave pulses that is applied to each driver of each proximity sensor / switch 22. The controller 40 processes the control procedure 100 stored in memory to monitor and make decisions regarding the activation of one of the proximity switches.

In FIG. 6-13, a change in the pulse count of the sensor sensor charge, shown as the sensor count delta (ΔSensorCount) for the plurality of signal paths associated with the plurality of proximity switches 22, such as the three switches 22 shown in FIG. 3 is illustrated according to various examples. The change in the count of the pulse of the charge of the sensor is the difference between the initialized reference value of the count without any finger or other object present in the field of excitation, and the corresponding reading of the sensor. In these examples, the user's finger penetrates the field 32 of the excitation associated with each of the three proximity switches 22, usually one field of excitation to determine at a time with the overlap between adjacent fields 32 of the excitation as the user's finger moves through the array of switches. Channel 1 - change (Δ) of the pulse count of the sensor charge associated with the first capacitive sensor 24, channel 2 - change of the pulse count of the sensor charge associated with the adjacent second capacitive sensor 24, and channel 3 - change of the pulse count of the sensor charge associated with the third capacitive a sensor 24 adjacent to the second capacitive sensor. In the disclosed embodiment, the proximity sensors 24 are capacitive sensors. When the user's finger is in contact with or in close proximity to the sensor 24, the finger changes the capacitance measured by the corresponding sensor 24. The capacitance is parallel to the stray capacitance of the unaffected sensor area and is essentially measured as an offset. The capacitance induced by the user or the operator is proportional to the dielectric constant of the finger or other part of the user's body, the surface exposed to the capacitive pad, and inversely proportional to the distance of the user's limb to the switch button. According to one embodiment, each sensor is excited by a series of voltage pulses by means of pulse width modulation (PWM) electronics until the sensor is charged to a set voltage potential. This data acquisition method charges the receiving electrode 28 to a known voltage potential. The cycle is repeated until the voltage across the measuring capacitor reaches the set voltage. The location of the user's finger on the touch surface of the switch 24 introduces an external capacitance, which increases the amount of charge transmitted in each cycle, thereby reducing the total number of cycles required for the measuring capacitance to reach a given voltage. The user's finger causes the change in the count of impulses of the charge of the sensor to increase, since this value is based on the initialized reference count minus the reading of the sensor.

The contactless switching unit 20 is capable of recognizing the movement of the user's hand when the hand, in particular the finger, is in close proximity to the contactless switches 22, in order to distinguish whether the intention of the user is to activate the switch 22, to feel for a specific switch button, meanwhile, focusing on higher priority tasks, such as driving, or is the result of a task, such as adjusting the rear view mirror, which has nothing to do with driving the operation of the proximity switch 22. The proximity switch unit 20 may operate in a fumble or search mode, which enables the user to fumble on keypads or buttons by swiping or sliding a finger in the immediate vicinity of the switches without initiating activation of the switch until the user's intention is determined . The non-contact switching unit 20 controls the amplitude of the signal generated in response to the field of excitation, determines the differential change in the generated signal and generates an activation output signal when the differential signal exceeds a threshold value. As a result, it is possible to feel for the contactless switching unit 20, so that users are free to feel for the interface pad with the switches with their fingers without unintentionally triggering an event, the response time of the interface is fast, activation occurs when the finger contacts the surface panel, and inadvertent activation of the switch is prevented or reduced .

With reference to FIG. 6, as the user's finger 34 approaches the switch 22 associated with the signal path 1, the finger 34 penetrates the excitation field 32 associated with the sensor 24, which causes a capacity violation, thereby resulting in an increase in the count of the sensor, as shown by signal 50A having a typical activation motion profile. The slope method of the input slope can be used to determine whether the operator intends to press a button or grope the interface based on the slope of the input slope in signal 50A of channel 1 signal increasing from point 52, where signal 50A crosses the active level account (LVL_ACTIVE), up to the point 54, where the signal 50A crosses the threshold level account (LVL_THRESHOLD), according to one embodiment. The steepness of the input slope is a differential change in the generated signal between points 52 and 54, which occurred during the time period between the times t _th and t _ac time. Since the numerator, the threshold level is the active level, as a rule, it changes only while gloves are detected, but otherwise is a constant value, the slope can be calculated simply as the time elapsed before the transition from the active level to the threshold level indicated by the link like t _{active2threshold} , which is the difference between the times t _th and t _ac time. Direct pressing of the switch pad may occur in a period of time indicated by reference as t _directpush in the range of about 40 to 60 milliseconds. If the time t _{active2threshold is} less than or equal to the time t of _direct direct push, then it is determined that the switch should be activated. Otherwise, the switch is determined to be in the fumble mode.

According to another embodiment, the slope of the input slope can be calculated as the time difference between from time t _ac time at point 52 to time t _pk to reach the peak count value at points 56, referred to as time t _active2peak . The time t _active2peak can be compared with the peak of the direct click indicated by the link as t _{direct_push_pk} , which can have a value of 100 milliseconds according to one embodiment. If the time t _{active2peak is} less than or equal to t _{direct_push_pk} , it is determined that activation should occur. Otherwise, the switch assembly operates in the fumble mode.

In the example shown in FIG. 6, the signal of channel 1 is shown to increase as the capacity violation increases, rapidly increasing from point 52 to a peak value at point 56. The contactless switching unit 20 determines the slope of the input slope as the time period t _{active2threshold} or t _active2peak so that the signal increases from point 52 of the first threshold value to one of the second threshold value at point 54 or a peak threshold value at point 56. The change in slope or differential change in the generated signal is then used to compare with the threshold a value t _{direct_push} or t _{direct_push_pk} characteristic direct pressing to determine activation of the proximity switch. More precisely, when the time t _{active2peak is} less than t _{direct_push} , or t _{active2threshold is} less than t _{direct_push} , the activation of the switch is determined. Otherwise, the switch assembly remains in the fumble mode.

With reference to FIG. 7, one example of a sliding / groping movement through two switches is illustrated as a finger passes or slides through an excitation field of two adjacent proximity sensors, shown as a signal transmission channel 1 labeled 50A and a signal transmission channel 2 labeled 50B. As the user's finger approaches the first switch, the finger penetrates the field of excitation associated with the sensor of the first switch, causing the change in the count of the sensor by signal 50A to increase at a slower speed, so that a smaller differential change in the generated signal is detected. In this example, the profile of channel 1 of the signal transmission experiences a change in time t _active2peak , which is not less than or equal to t _{direct_push} , thereby resulting in entry into search or groping mode. Since t _{active2threshold} is indicative of a slow differential change in the generated signal, the activation of the switch button is not triggered, according to one embodiment. According to another embodiment, since the time t _{active2peak is} not less than or equal to t _{direct_push_pk} , indicating a slow differential change in the generated signal, activation is not triggered, according to another embodiment. The second signal path, labeled 50B, is shown as becoming the maximum signal at the transition point 58 and has an increasing change in the sensor count Δ with a differential signal change similar to that of the signal 50A. As a result, the first and second channels 50A and 50B reflect the sliding movement of a finger through two capacitive sensors in the fumble mode, resulting in the absence of activation of both switches. Using the period t _{active2threshold} or t _active2peak time, it may be decided to activate or not activate the proximity switch, since its capacitance reaches the peak of the signal.

For a slow movement of immediate pressing, such as that shown in FIG. 8. Additional processing may be used to ensure activation is not implied. As seen in FIG. 8, the signal path 1 identified as signal 50A is shown to increase more slowly during the period t _{active2threshold} or t _active2peak time, which would result in entering the fumble mode. When such a slip / groping state is detected with a time t _{active2threshold} greater than t _{direct_push} if the _stateless channel was the first signal transmission channel entering the groping mode and it is still the maximum channel (the channel with the highest intensity ), since its capacity drops below the threshold value LVL_KEYUP (button release level) at point 60, the activation of the switch is initiated.

With reference to FIG. 9, a quick movement of a user's finger through a contactless switching unit without activating switches is illustrated. In this example, a relatively large differential change in the generated signal is detected for channels 1 and 2 shown by lines 50A and 50B, respectively. The switch node applies a delayed period of time to delay the activation of the solution to the transition point 58, in which the second channel 50B signal transmission increases above the first channel 50A signal transmission. The time delay could be set equal to the threshold value t _{direct_push_pk} time according to one embodiment. Thus, by applying a delayed period of time before determining the activation of the switch, the very quick feel of the contactless keypads prevents the switch from being unintentionally activated. Introducing a time delay into the reaction may make the interface less sensitive and may respond better when the movement of the operator’s finger is substantially uniform.

If a previous threshold event that did not result in activation has been detected recently, the groping mode may be entered automatically according to one embodiment. As a result, as soon as inadvertent commissioning is detected and rejected, greater care may be taken for a period of time in the fumble mode.

Another way to enable the operator to enter the groping mode is to use one or more appropriately labeled and / or texted zones or sites on the surface of the switch panel associated with special proximity switches, with a function to signal the proximity switch node of the operator’s intention to feel blindly. One or more of the groping input sites may be located in an easy-to-access location, unlikely to generate activity with other signal paths. According to yet another embodiment, an unmarked large groping input site surrounding the entire interface with the switches can be used. Such a groping area would probably be the first to occur, while the operator’s hand slides parallel to the interior trim on the console above the windshield, looking for a reference point from which to begin the blind groping of the contactless switching unit.

As soon as the proximity sensor assembly determines whether an increase in the change in the sensor’s count is an activation or the result of a groping movement, the node continues to determine whether or not the sensing movement should be completed by activating the proximity switch. According to one embodiment, the contactless switching unit searches for stable pressing of the switch button for at least a predetermined time. In one specific embodiment, the predetermined time is equal to or greater than 50 milliseconds, and more preferably, has a value of approximately 80 milliseconds. Examples of operation of the switching unit using the stable time methodology are illustrated in FIG. 10-13.

With reference to FIG. 10, the fumble of three proximity switches corresponding to channels 1 through 3 of the signal labeled 50A-50C, respectively, is illustrated, while the finger slides parallel to the first and second switches in the fumble mode, and then, activates the third switch associated with channel 3 signal passage. As the finger finds the first and second switches associated with channels 1 and 2, activation is not detected due to the lack of a stable signal on lines 50A and 50B. The signal on line 50A for channel 1 starts as the maximum value of the signal until channel 2 on line 50B becomes the maximum value and, finally, channel 3 becomes the maximum value. The signal path 3 is shown to have a stable change in sensor count near a peak value for a sufficient period t _stable time, such as 80 milliseconds, which is sufficient to initiate activation of the corresponding proximity switch. When the threshold level initiation condition has been satisfied and a peak has been reached, the stable level method activates the switch after the level on the switch is limited in the compressed range for at least a period t _stable time. This provides the operator with the opportunity to grope various proximity switches and activate the desired switch as soon as it is found, supporting the user's finger in the vicinity of the switch for a stable period of t _stable time.

With reference to FIG. 11, another embodiment is illustrated in which the third signal path on line 50C has a change in signal count, which has a stable state on signal drop. In this example, the change in the sensor count for the third channel exceeds the threshold level and has a stable depression detected during the t _stable time period, so that the activation of the third switch is determined.

According to yet another embodiment, the non-contact switching unit may apply a virtual button method that searches for the initial peak value of the change in the sensor count, while in the fumble mode, followed by an additional continuous increase in the change in the sensor count to decide to activate the switch, as shown in FIG. . 12 and 13. FIG. 12, the third signal path on line 50C increases up to the initial peak value, and then further increases by changing the count C _{vb of the} sensor. This is equivalent to the user's finger, gently touching the surface of the switching unit as it slides parallel to the switch unit, reaching the desired button, and then pressing the virtual mechanical switch, so that the user's finger presses on the contact surface of the switch and increases the volume of the finger, more close to the switch. The increase in capacity is caused by the increased surface of the fingertip, while it is pressed against the surface of the pad. Increased capacitance may occur immediately following the detection of the peak value shown in FIG. 12, or may occur following a decrease in the change in the count of the sensor, as shown in FIG. 13. The contactless switching unit detects the initial peak value, followed by a further increased change in the count of the sensor indicated by the capacitance C _vb at a stable level or a stable period t _stable time. A stable detection level generally means that there is no change in the counting value of the sensor in the absence of interference, or a small change in the counting value of the sensor in the absence of interference, which can be set during calibration.

It should be noted that a shorter period of t _stable time can lead to random activations, especially accompanying a change in the direction of finger movement in the opposite, and that a longer period of t _stable time can lead to a less sensitive interface.

It should also be taken into account that both the stable value method and the virtual button method can be effective simultaneously. By acting in this way, t _stable can be softened to be longer, such as one second, since the operator can always actuate the button using the virtual button method without waiting for a stable pressing timeout.

The non-contact switching unit can additionally apply reliable interference suppression to prevent annoying careless actuation. For example, with a console above the windshield, accidental opening and closing of the sunroof should be avoided. Too much interference suppression may result in a rejection of intentional activations, which should be avoided. One approach to suppressing interference is to examine whether multiple adjacent channels report simultaneous triggering of events and, if so, by selecting the signal path with the highest signal and activating it, thereby ignoring all other signal paths before releasing the selected channel signal passing.

The non-contact switching unit 20 may include a method for suppressing interference in the recorded characteristic based on two parameters, namely, the parameter of the registered characteristic, which is the ratio of the channel between the highest intensity (maximum channel, max_channel) and the total accumulated level (total channel, sum_channel) , and dac, which is the number of channels that are at least some maximum channel ratio. In one embodiment, dac α _dac = 0.5. The parameter of the recorded characteristic can be determined by the following equation:

.recorded characteristic =

.

The parameter dac can be defined by the following equation:

dac = ∀channels _i > α _dac max_channel.

Depending on dac, in order for the recognized activation not to be rejected, the channel should be generally clean, that is, the recorded characteristic should be higher than the set value. In one embodiment, α _{dac = 1} = 0.4 and α _{dac = 2} = 0.67. If the dac is greater than 2, activation is rejected according to one embodiment.

When the decision to activate or not the switch is made in the falling phase of the profile, then, instead of max_channel and sum_channel, their peak values peak_max_channel and peak_sum_channel can be used to calculate the recorded characteristic. The recorded characteristic may have the following equation:

.signature =

.

A search mode with interference suppression triggers may be used. When the detected activation is rejected due to a dirty signature, the search or groping method should be automatically put into effect. Thus, when groping blindly, the user can reach with all outstretched fingers, hoping to establish a frame of reference with which to start the search. This can trigger multiple channels at the same time, thereby resulting in a poor recorded characteristic.

With reference to FIG. 14, a state graph is shown for a contactless switching unit 20 in a state machine implementation according to one embodiment. A state machine implementation is shown having five states, including state 70 SW_NONE (undefined switch state), state 72 SW_ACTIVE (active state of the switch), state 74 SW_THRESHOLD (threshold state of the switch), state 76 SW_HUNTING (state of search for the switch), and state 78 SWITCH_ACTIVATED (switch activated). State 70 SW_NONE is a state in which there is no detected sensor activity. The SW_ACTIVE state is a state in which some activity is detected by the sensor, but not sufficient to initiate the activation of the switch at that time. The SW_THRESHOLD state is a state in which the activity as detected by the sensor is high enough to serve as the basis for activation, search / groping or accidental movement of the switching node. State 76 SW_HUNTING begins when an activity stereotype as defined by a switch node is comparable to a groping / searching interaction. State 78 SWITCH_ACTIVATED is the state in which the activation of the switch has been identified. In state 78 SWITCH_ACTIVATED, the switch button will remain active and no other selection will be possible until the corresponding switch is released.

The state of the contactless switching unit 20 changes depending on the detection and processing of the read signals. When in state 70 SW_NONE, the node 20 can advance to state 72 SW_ACTIVE when some activity is detected by one or more sensors. If sufficient activity is detected to serve as the basis for activation, search, or random movement, the node 20 can go directly to state 74 SW_THRESHOLD. When in state 74 SW_THRESHOLD, node 20 may transition to state 76 SW_HUNTING when a stereotype indicating a grope is detected, or may go directly to state 78 of the activated switch. When the activation of the switch is in the SW_HUNTING state, the activation of the switch can be detected to enter the state 78 SWITCH_ACTIVATED. If the signal is rejected and an inadvertent action is detected, the node 20 may return to the SW_NONE state 70.

With reference to FIG. 15, the main method 100 for monitoring and determining when to activate the output signal of the activation by the proximity switch device, according to one embodiment. The method 100 begins at step 102 and proceeds to step 104 to perform initial calibration, which can be performed once. The calibrated values of the signal path are calculated from the source channel data and the calibrated reference values by subtracting the reference value from the source data at step 106. Then, at step 108, from all the readings of the sensors of the signal path, the highest count value is calculated, referred to as max_channel, and the sum of all readings of the signal transmission channel sensors indicated by the reference as sum_channel. In addition, the number of active channels is determined. At step 110, method 100 calculates a recent range of max_channel and sum_channel to later determine whether or not movement is currently taking place.

Following step 110, the method 100 proceeds to decision block 112 to determine if any of the switches are active. If the switches are not active, method 100 proceeds to step 114 to perform real-time interactive calibration. Otherwise, the method 116 processes the release of the switch in step 116. Accordingly, if the switch was already active, then the method 100 goes to the module, where it waits and blocks all activity until it is released.

Following the real-time calibration, the method 100 proceeds to decision block 118 if there is a channel lock indicating recent activation and, if so, proceeds to step 120 to decrease the channel lock timer. If channel locks are not detected, method 100 proceeds to decision block 122 to look for a new max_channel. If the current max_channel has changed, so there is a new max_channel, method 100 proceeds to step 124 to reconfigure max_channel, sum the ranges, and set threshold levels. Thus, if a new max_channel is identified, the method resets the new signal ranges and updates, if necessary, the search / fumble parameters. If switch_status (switch state) is less than SW_ACTIVE, then the search / feel flag is set to true, and the switch state is set to SW_NONE. If the current max_channel has not changed, the method 100 proceeds to step 126 to process the state of the bare (without gloves) finger max_channel. This may include processing logic between different states, as shown in the state graph of FIG. fourteen.

Following step 126, method 100 proceeds to decision step 128 to determine if any switch is active. If there is a lack of activation of the switches, the method 100 proceeds to step 130 to detect the possible presence of a glove on the user's hand. The presence of a glove can be detected based on a reduced change in the value of the capacity account. Method 100 then proceeds to step 132 to update the history of max_channel and sum_channel. The index of the active switch, if any, is then output to the firmware module at step 134 before ending at step 136.

When the switch is active, the switch release processing procedure that is shown in FIG. 16. The switch release processing procedure 116 starts at step 140 and proceeds to decision block 142 to determine if the active channel is less than LVL_RELEASE (release level), and if so, ends at step 152. If the active channel is less than LVL_RELEASE, then procedure 116 proceeds to decision block 144 to determine whether LVL_DELTA_THRESHOLD (threshold delta level) is greater than 0, and if not, proceeds to step 146 to raise the threshold level if the signal is more powerful. This can be achieved by lowering LVL_DELTA_THRESHOLD. Step 146 also sets a threshold level, a release level, and an activation level. Procedure 116 then proceeds to step 148 to reset the timer of the history of the maximum value and the sum of the channels for the search / groping parameters of a long-term stable signal. The switch state is set to SW_NONE in step 150 before ending in step 152. To exit the switch release processing module, the signal in the active channel must fall below LVL_RELEASE, which is the adaptive threshold value that will change while the interaction in the glove is detected. While the switch button is released, all internal parameters are reset, and the lock timer starts to prevent additional activations before a specific timeout, such as 100 milliseconds, has elapsed. Additionally, threshold levels are adapted as a function of the presence or absence of gloves.

With reference to FIG. 17, a procedure 200 for determining a state transition from the SW_NONE state to the SW_ACTIVE state, according to one embodiment, is illustrated. Procedure 200 begins at block 202 to process the SW_NONE state, and then proceeds to decision block 204 to determine if max_channel is larger than LVL_ACTIVE. If max_channel is greater than LVL_ACTIVE, then the contactless switching node changes state from SW_NONE to SW_ACTIVE and ends at step 210. If max_channel is not greater than LVL_ACTIVE, procedure 200 checks whether the search flag should be cleared at step 208 before ending at step 210. Thus, the state changes from the SW_NONE state to the SW_ACTIVE state when max_channel is triggered above LVL_ACTIVE. If the channels remain below this level, after a certain waiting period, the check flag of the search, if set, becomes cleared in the absence of a search, which is one way to exit the search mode.

With reference to FIG. 18, a method 220 for processing a state of a state SW_ACTIVE transitioning to a state SW_THRESHOLD or a state SW_NONE, according to one embodiment, is illustrated. Method 220 begins at block 222 and proceeds to decision block 224. If max_channel is not greater than LVL_THRESHOLD, then method 220 proceeds to step 226 to determine whether max_channel is less than LVL_ACTIVE and, if so, proceeds to step 228 to switch the state of the switch to SW_NONE. Accordingly, the state of the state machine goes from the SW_ACTIVE state to the SW_NONE state when the signal max_channel falls below LVL_ACTIVE. The delta value can also be subtracted from LVL_ACTIVE to enter some hysteresis. If max_channel is greater than LVL_THRESHOLD, then procedure 220 proceeds to decision block 230 to determine whether the last threshold event or glove was detected and, if so, sets a flag flag equal to the true value, in block 232. At step 234, method 220 switches the state to the SW_THRESHOLD state before ending at step 236. Thus, if the maximum channel is triggered above LVL_THRESHOLD, the current state goes to the SW_THRESHOLD state. If gloves are found, or recently a previous threshold event that did not lead to activation has been detected, the search / groping mode may automatically start.

With reference to FIG. 19, a method 240 for determining activation of a switch from the SW_THRESHOLD state according to one embodiment is illustrated. Method 240 starts at step 242 to process the state of SW_THRESHOLD, and moves to decision block 244 to determine if the signal is stable, or if the signal channel is at a peak, and if not, ends at step 256. If the signal is stable or if the signal path is at its peak, then method 240 proceeds to decision block 246 to determine if the search or groping mode is active, and, if so, proceeds immediately to step 250. If the search or groping mode is not active, method 240 proceeds to decision block 248 ia to determine if the signal path is clean and often active, and is greater than the threshold, and if so, sets the active switch to the maximum channel in step 250. Method 240 goes to decision block 252 to determine if there is an active switch, and if so, ends at step 256. If there is no active switch, method 240 proceeds to step 254 to initialize the search variables, SWITCH_STATUS set to SWITCH_HUNTING, and PEAK_MAX_BASE (peak maximum base channel) equal MAX_CHANNELS (the maximum value of the channel), before ending at block 256.

In state SW_THRESHOLD, no decision is made until a peak is detected in MAX_CHANNEL. Peak detection is determined by reversing the direction of the signal, or both, MAX_CHANNEL and SUM_CHANNEL remaining stable (limited in range) for at least some interval, such as 60 milliseconds. As soon as the peak is detected, the check flag of the search is checked. If the search mode is turned off, the slope method of the input slope is applied. If SW_ACTIVE for SW_THRESHOLD was less than a threshold value, such as 16 milliseconds, and the recorded characteristic of the interference suppression method indicates it as a real trigger event, then the state switches to SWITCH_ACTIVE and the processing is passed to the PROCESS_SWITCH_RELEASE module (switch release processing), otherwise, a flag the search attribute is set equal to the true value. If the delayed activation method is used instead of immediately activating the switch, the state changes to SW_DELAYED_ACTIVATION (delayed activation of the switch), where the delay is forcibly applied, at the end of which, if the current MAX_CHANNEL index has not changed, the button is activated.

With reference to FIG. 20, a virtual button method that implements the SW_HUNTING state according to one embodiment is illustrated. Method 260 begins at step 262 to process the SW_HUNTING state, and continues at decision block 264 to determine whether MAX_CHANNEL has fallen below LVL_KEYUP_THRESHOLD, and if so, sets MAX_PEAK_BASE to MIN (MAX_PEAK_BASE, MAX_CHANNEL) at step 272. If MAX_CHANNEL has fallen below LVL_KEYUP_THRESHOLD, then method 260 proceeds to step 266 to apply the first channel initiating search method to check whether the event should trigger button activation. This is determined by determining whether the first and only channel crosses and whether the signal is clear. If so, method 260 sets the active switch to the maximum channel in step 270 before ending in step 282. If the first and only channels do not cross, or if the signal is not clear, method 260 proceeds to step 268 to open and determine the unintentional actuation and set SWITCH_STATUS to the state of SW_NONE before ending at step 282.

Following step 272, method 260 proceeds to decision step 274 to determine if a channel is selected by pressing. This can be determined by whether MAX_CHANNEL is greater than MAX_PEAK_BASE plus delta. If the channel is selected by pressing, method 260 proceeds to decision block 276 to determine whether the signal is stable and, if so, sets the active state of the switch to the maximum channel in step 280 before ending in step 282. If the channel is not selected by pressing, method 260 proceeds to decision block 278 to determine if the signal is long, stable and clean, and, if so, proceeds to step 280 to set the active switch to the maximum channel before terminating in step 282.

The non-contact switching unit 20 may include a virtual button mode according to another embodiment. With reference to FIG. 21-27, there is shown a contactless switching unit having a virtual button mode and a method for activating a proximity switch with a virtual button mode according to this embodiment. The proximity switch assembly may include one or more proximity switches, each providing an excitation field for determining and a circuit for controlling an excitation field of each proximity switch for determining activation. The control circuit monitors signals indicating excitation fields, determines a first stable signal amplitude for a time period, determines a next second stable signal amplitude for a time period, and generates an activation output signal when the second stable signal exceeds the first stable signal by a known amount. The method can be used by a proximity switch assembly and includes the steps of generating an excitation field associated with each one or more of the plurality of proximity sensors, and monitoring a signal indicating each associated excitation field. The method also includes the steps of determining a first amplitude when the signal is stable for a minimum period of time, and determining a second amplitude when the signal is stable for a minimum period of time. The method further includes the step of generating an activation output when the second amplitude exceeds the first amplitude by a known amount. As a result, a virtual button mode is provided for a proximity switch that prevents or reduces inadvertent or false activations that can be caused by a finger feeling for a plurality of proximity switch buttons and changing directions, or a finger covered with a glove.

In FIG. 21, the fumble and activation of the proximity switch are shown for one of the signal paths marked as signal 50, while the user's finger slides across the corresponding switch, enters the fumble mode and continues to activate the switch in virtual button mode. It will be appreciated that a user's finger may feel for a plurality of capacitive switches, as illustrated in FIG. 10-12, in which the signals associated with each of the respective signal transmission channels are generated as the finger passes through the excitation field of each channel. A plurality of signal paths can be processed simultaneously, and a maximum signal path can be processed to determine activation of the corresponding proximity switch. In the examples provided in the waveforms of FIG. 21-25, a single signal path associated with one switch is shown, however, multiple signal paths could be processed. A signal 50 associated with one of the signal paths is shown in FIG. 21 increasing up to the threshold active level 320 at point 300, at which moment, the signal enters the groping mode. The signal 50, after that, continues to increase and reaches the first amplitude, at which point the signal is stable for the minimum period of time, shown as Tstable, which is shown at point 302. At point 302, signal 50 enters the virtual button mode and sets the first the base value of Cbase, which is the signal counting delta at point 302. At this point, the virtual button mode sets the activation threshold specified by increments depending on the base value of Cbase multiplied by the constant K _vb. The activation threshold for determining activation can be represented according to: (1 + K _vb ) × Cbase, with K _{vb being} a constant greater than zero. The virtual button mode continues to monitor the signal 50 to determine when it reaches the second stable amplitude for the minimum time period Tstable that occurs at point 304. At this point 304, the virtual button mode compares the second stable amplitude with the first stable amplitude and determines whether the second amplitude the first amplitude by a known value of K _vb × Cbase. If the second amplitude exceeds the first amplitude by a known amount, then an activation output signal is generated for the proximity switch.

According to this embodiment, a stable signal amplitude must be maintained by the signal path for at least a minimum period Tstable before entering the virtual button mode or determining the activation of the switch. The value of the sensor, while it enters virtual button mode, is registered as Cbase. The method controls when the next stable signal amplitude is again reached before the timeout period. If a stable signal amplitude is reached again before the timeout period has elapsed with a delta count value greater than the required percentage, such as 12.5 percent of the previously registered Cbase, then activation is triggered. According to one embodiment, the delta in percent of the increase in the signal count of at least 10 percent is provided by K _vb × Cbase.

The K _vb factor is a coefficient of at least 0.1 or at least 10 percent of the Cbase value according to one embodiment. According to another embodiment, the factor K _{vb is} set to approximately 0.125, which is equivalent to 12.5 percent. A stable time period Tstable may be set to a time of at least 50 milliseconds according to one embodiment. According to yet another embodiment, a stable period of time Tstable can be set in a range of 50 to 100 milliseconds. The stable amplitude can be determined by the amplitude of the signal, which is essentially stable in the range between the double value of the estimated interference in the signal according to one embodiment, or in the range from 2.5 to 5.0 percent of the signal level according to another embodiment, or a combination of the double estimated signal interference added to from 2.5 to 5.0 percent signal strength, according to a further embodiment.

With reference to FIG. 22, the signal 50 for the signal path associated with the proximity switch is illustrated entering into the fumble mode at point 300 and proceeding to achieve a stable first amplitude when a stable amplitude of the signal exists for a minimum period of time Tstable at point 302 at which the virtual mode starts buttons. At this point, the value of Cbase is determined. After that, the signal 50 is shown to be falling and rising to the second amplitude, when the signal is stable for a minimum period of time Tstable at point 306. However, in this situation, the second amplitude at point 306 does not exceed the base value Cbase of the signal at point 302 by a known amount K _vb × Cbase and, as a result, does not generate an activation output for the switch.

With reference to FIG. 23, the signal 50 associated with the signal path is illustrated entering groping mode at a point 300 and continuing to reach a first amplitude for a stable period Tstable time at a point 302 at which the virtual button mode starts, and Cbase is determined. After that, the signal 50 continues to increase to a second amplitude, which is stable for a minimum period of time Tstable at point 308. However, at point 308, the second amplitude does not exceed the base value Cbase of the signal set at the first amplitude at point 302 by a known value of K _vb × Cbase, therefore, the contactless switching node does not initiate the switch output. However, a new updated baseline value is generated for Cbase at 308 and is used to determine a known value for comparison with the next stable amplitude. Signal 50 is shown to be incident and then rising to a third amplitude, which is stable for a minimum period of time Tstable at point 310. The third amplitude exceeds the second amplitude by more than the known value K _vb × Cbase, so that an activation output signal is generated for the switch.

With reference to FIG. 24, another example of a signal 50 is illustrated by entering a groping mode at a point 300 and continuing to rise to a first amplitude that is stable for a minimum period of Tstable time at a point 302 at which the virtual button mode starts, and Cbase is determined. After that, the signal 50 is shown to drop to a second amplitude, which is stable for a minimum period of time Tstable at point 312. At point 312, the second amplitude does not exceed the first amplitude by a known value of K _vb × Cbase, so that signal initiation is not generated. However, an updated baseline Cbase value is generated at point 312. After this, the signal 50 continues to increase to a third amplitude, which is stable for a minimum period of time Tstable at point 310. The third amplitude exceeds the second amplitude by a known value of K _vb × Cbase, so that initiation or activation output for the switch.

With reference to FIG. 25, another example of a signal 50 for a signal path is shown, entering groping mode at point 300 and continuing to reach a first amplitude that is stable for a minimum period of time Tstable at point 302, and therefore enters virtual button mode and determines Cbase. Then, the signal 50 continues to increase to a second amplitude, which is stable for a period of Tstable time at a point 308. The second amplitude does not exceed the first amplitude by a known amount, so that the switch does not form at that moment. After that, the signal 50 is shown falling to point 314 and, in the process of doing so, the reset timer counts down the timeout, since the last stable amplitude was received, as shown by the time Treset. When the reset timer counts down the timeout, at 314, the virtual button mode ends and the palpable mode starts as soon as the virtual button mode ends. When this happens, the preceding specific Cbase is no longer valid. After that, the signal 50 is shown rising up to the third amplitude, which is stable for a minimum period of time Tstable at point 316. At this point, the third amplitude sets the updated Cbase, which is used to determine future activations of the switch. After that, the signal 50 is additionally shown falling below the threshold active value 320, in which case, the virtual button mode is terminated without any activations.

A method for activating a proximity switch with a virtual button mode using the proximity switch node is illustrated in FIG. 26 and 27. With reference to FIG. 26, method 400 begins at step 402 and continues to collect data from all signal paths associated with all the proximity switches, at step 404. Method 400 proceeds to decision block decision block 406 to determine if the state is in the (active) state ACTIVE, and if so, checks the release of the switch in step 414 before ending in step 416. If the state is not set to ACTIVE, method 400 proceeds to step 408 to determine the maximum channel (CHT). Then, once the maximum channel has been found, the procedure 400 proceeds to step 410 to process the maximum channel virtual button (CHT) method before terminating in step 416. The maximum processing channel virtual button method 410 is illustrated in FIG. 17 and is described below. It will be appreciated that method 400 may include a possible step 412 also for processing a maximum channel signal using a finger stroke method to detect a user's finger being struck by a proximity switch to generate an activation output signal.

The virtual button method 410 of the maximum processing channel shown in FIG. 27 starts at step 420 and proceeds to step 422 to input a maximum channel signal. From here, the maximum signal path associated with one of the proximity switches is processed to determine the state of the virtual button mode and the activation of the switch. At decision block 424, method 410 determines whether the switch is set to the virtual button mode state, and, if so, proceeds to decision block 426 to determine if the signal path is less than the active threshold. If the signal path is less than the active threshold, method 410 proceeds to step 428 to set the state to NONE and returns to the beginning. If the signal path is not less than the active threshold, method 410 proceeds to decision block 430 to determine if the signal has a stable first amplitude for a period of time longer than a stable period of Tstable time. If the stable signal path at the first amplitude is stable for a time period longer than Tstable, method 410 proceeds to decision block 432 to determine whether the signal path is unstable for a time period longer than the reset time period Treset, and if not, returns to step 422. If the signal path is not stable for a period of time longer than the reset time period Treset, method 410 proceeds to set the state to the state of the grope / search and ends I'm at step 460.

Returning to decision block 430, if the signal path is stable for a period of time longer than the stable time period Tstable, method 410 proceeds to decision block 436 to determine if the signal Ch (t) is larger than Cbase by a known amount determined according to the K _vb × C _base , and if so, sets the switch state to active to generate an activation output signal before ending at step 460. If the signal does not exceed Cbase by a known value of K _vb × C _base , method 410 proceeds to install new Cbase th value in the current stable amplitude of the signal at step 440 before ending at block 460.

Returning to decision block 424, if the state of the switch is not set to virtual button mode, method 410 proceeds to decision block 442 to determine whether the state is set to the fumble state and, if so, proceeds to decision block 444 to determine whether the signal is larger than the active threshold and, if not, sets the state to NONE and ends at step 460. If the signal is larger than the active threshold, method 410 proceeds to decision block 448, to determine whether the signal is stable in amplitude for a time period exceeding the minimum time period, Tstable, and if not, ends at step 460. If the signal is stable in amplitude for a time period exceeding the minimum time period, Tstable, method 410 proceeds at step 450, to set the state to switch to the state of the virtual button and set a new Cbase value for the signal path at step 450 before ending at step 460.

Returning to decision block 442, if the switch state is not set to the groping / searching state, method 410 proceeds to decision block 452 to determine if the signal is larger than the active threshold and, if not, ends at block 460. If the signal is greater than the active threshold, method 410 proceeds to decision block 454 to set the state to the groping / searching state before ending at block 460.

Accordingly, a non-contact switching unit having a virtual button method 410 advantageously provides improved detection of a virtual button switch activation and an improved rejection of unintentional activations. Method 410 can advantageously detect switch activation along with the rejection of unintentional activations that can be detected when the finger gropes for the switch assembly and reverses direction, or in which the user's finger is wearing a glove. Improved activation detection predominantly provides an improved contactless switching node.

Accordingly, the determination procedure advantageously determines the activation of proximity switches. The procedure advantageously provides the opportunity for the user to feel for the contactless sensor sites, which can be especially useful in automotive applications where distraction of the driver's attention can be avoided.

The proximity switch assembly 20 may include malleable material covering the proximity sensor, and the control circuit may activate the proximity switch based on a signal generated by the sensor relative to the threshold value when the user's finger presses the malleable material, according to a further embodiment. In this embodiment, the non-contact switching unit 20 can operate in a virtual button mode and can provide improved signal detection using malleable material that is deformed to allow the user's finger to move closer to the non-contact sensor. In addition, free space in the form of an air pocket may be provided between the compliant material and the proximity sensor, and a convex or protruding surface may be further provided in the compliant material.

With reference to FIG. 28A-31, there is shown a contactless switching unit 20 using compliant material and operating in a virtual button mode, and a method for activating a contactless switch using compliant material in a virtual button mode according to this embodiment. The proximity sensor assembly 22 may include a proximity sensor, such as a capacitive sensor, generating an excitation field. It will be appreciated that a plurality of proximity sensors 24 may be used, each generating an excitation field. Contactless sensors 24 are shown provided on the surface of a rigid substrate, such as a polymer console 12 above a windshield, according to one embodiment. Each of the proximity sensors 24 can be formed by printing conductive printing ink on the surface of the polymer console 12 above the windshield. The proximity sensors 24 can be formed differently, for example, by mounting preformed conductive traces of the circuit on a substrate according to other embodiments.

A pliable material 500 is shown covering the substrate 12 and is intended to provide a touch surface for the user's finger 34 to interact with proximity sensors 24 to activate the switches 22. The pliable material 500 is shown formed as a cover layer that can be made of an elastic material, including , rubber, according to one embodiment. The pliable material 500 is relatively flexible with respect to the underlying substrate 12, which is typically rigid. The compliant material 500 covers the proximity sensor 24 and is deformable when the user's finger 34 applies pressure, so that the finger 34 compresses the flexible material 500 and moves inward toward the proximity sensor 24, as shown in FIG. 28C. According to one embodiment, the compliant material 500 may have a layer thickness in the range of about 0.1 to 10 millimeters, and more preferably, in the range of 1.0 to 2.0 mm.

The proximity switch assembly 20 employs a control circuit to monitor the field of excitation associated with each sensor 24 and to determine the activation of the proximity switch based on a signal generated by the proximity sensor 24 relative to a threshold value when the user's finger 34 presses compliant material 50. The control circuit can determine a stable the amplitude of the signal generated by the proximity sensor 24 for a predetermined period of time, and can generate a switch activation output signal When a stable output signal exceeds the threshold value. According to one embodiment, the control circuit may determine a first stable signal amplitude over a period of time, may determine a subsequent second signal amplitude over a period of time, and may generate an activation output signal for the proximity switch associated with the signal when the second stable signal exceeds the first stable signal by a known amount.

With reference to FIG. 28A-28D, the proximity switch assembly 20 is illustrated using a compliant material 500 covering one or more proximity sensors 24, according to the first embodiment. As seen in FIG. 28A, the user's finger 34, shown in the first position, contacts the surface of the compliant material 500 at a location close to but transversely offset from the proximity sensor 24. In FIG. 28B, the user's finger 34 is shown to slide sliding into a second position aligned with the proximity sensor 24 without applying pressure to the compliant material 500. This may occur when the user gropes for the proximity switching unit 20 in the grope / search mode without intent to activate switch 22. On FIG. 28C, the user's finger 34 is shown exerting force on the proximity sensor 24 to press the compliant material 500 to move the user finger 34 to a third position closer to the proximity sensor 24. The user finger 34 may therefore press and deform the flexible material 500 to move closer to the proximity sensor 24 and further flatten and thereby smooth the finger 34 on the substrate 12 to provide an increased surface area or volume of the finger in close proximity to the sensor 24, which gives a greater interaction with the associated excitation field and hence, a larger signal.

The sequence of events shown in FIG. 28A-28C is further illustrated in the response of the signal shown in FIG. 28D. The signal 506 generated by the proximity sensor 24 is shown rising to a first level 506A, indicating a user's finger 34 in contact with the proximity switching unit 20 in a first position transversely distant from the proximity sensor 24, as seen in FIG. 28A. The signal 506 then rises to a level 506B indicating the user's finger 34, shown in a second position aligned with the proximity sensor 24, without applying a force, as shown in FIG. 28B. After that, the signal 506 then rises to a third elevated level 506C, indicating a user finger 34 applying a force in the third position to press the pliable material 500, as shown in FIG. 28C. Thus, the signal 506 is much larger when the user's finger 34 presses on the compliant material 500, which enables improved detection of the virtual button.

The control circuit monitors the field of excitation and determines the activation of the proximity switch based on the signal 506 relative to the threshold value when the user's finger pushes the compliant material 500. The processing circuit may include the controller 400 shown in FIG. 5 to perform a control procedure, which may include a procedure 520 shown and described herein in connection with FIG. 31. Essentially, the processing circuit may use the virtual button method, as described above, to detect the fumble mode and activation of the virtual button of one or more proximity switches.

The non-contact switching assembly 20 may further be provided with compliant material 500 having a convex or protruding touch surface portion 502 aligned with each non-contact sensor 24 and a free space or air gap 504 located between the protruding portion 502 and the non-contact sensor 24, as shown in FIG. 24A-24C, according to another embodiment. In this embodiment, an air gap 504 formed between the compliant material 500 and each proximity sensor provides an increased travel distance during activation of the switch, which can also serve as a tactile sensation for the user. The air gap 504 may have a height distance of less than 5.0 millimeters, according to one embodiment, more preferably in the range of 1.0 to 2.0 millimeters. The protruding portion 502 of the compliant material 500 holds the user's finger 34 farther away from the proximity sensor 24. As shown in FIG. 29A, the user's finger 34 is in contact with the proximity switch assembly 20 in a position close to but transversely spaced from the proximity sensor 24 in a first position. Then, in FIG. 28B, the user's finger 34 is moved to a second position aligned with the proximity sensor 24 on the upper surface of the protruding portion 52 of the compliant material 500. In this position, the user finger 34 may be feeling for the proximity switches 22 in the grope / search mode without any intention activate the switch. In FIG. 29C, the user's finger 34 is shown in a third position pushing the compliant material 500 on top of the protruding portion 502 to move the finger 34 to a fully pressed state that compresses the compliant material 500 and the air gap 504 to allow the user finger to be in a closer position relative to the non-contact sensor 24. When this happens, the control circuit detects the user’s intention to activate the switch 22 and generates an activation output.

With reference to FIG. 28D, the signal 506 generated in response to the activation of the excitation field by the proximity sensor 24 is shown relative to the actuations of the user's finger shown in FIG. 29A-29C. The signal 506 is shown rising to a first level 506A indicating a user's finger 34 in a first position in contact with the contactless switching unit 20 at a transverse distance from the sensor 24 shown in FIG. 29A. Signal 506 remains at first level 506A, as also shown at level 506B, while the user's finger rises to a second position on a protruding portion 502 aligned over the proximity sensor 24. without pressing pliable material 500, as shown in FIG. 29B. The protruding portion 502, therefore, provides the signal 506 with the ability to maintain a low signal when the user's finger is in the fumble mode and does not intend to activate the switch 22. The signal 506 is shown increasing to an additionally elevated level 506C indicating the finger 34 of the user pressing the compliant material in the third position by compressing the protruding portion 502 and the air gap 504, as shown in FIG. 29C to activate the switch 22. The control circuit processes the signal 506 to detect the activation of the switch 22 when this happens, and, in addition, detect the groping / searching mode

With reference to FIG. 30, a state graph is shown for a contactless switching node in yet another implementation of a state machine that uses compliant material and virtual button mode, according to one embodiment. A state machine implementation is shown to have four states, including a wait state 510, a search state 512, a virtual button state 514, and a button click state 516. The standby state 510 begins when the signal is less than a threshold value indicating that there is no detected sensor activity. The search state 512 begins when the signal is greater than a threshold value indicating activity determined to be comparable with the fumble / search interaction. Virtual button state 514 starts when the signal is stable. The button press state 516 indicates a strong press on the switch to compress the pliable material as soon as the virtual button is in state. When the signal reaches a certain threshold value, the search / groping mode 512 begins. When the signal is stable and larger than the base level, virtual button mode 514 begins. If the signal is stable and greater than the base level plus the delta value of the domed button element, the button press mode 516 starts. It should be appreciated that the baseline may be updated as described above.

With reference to FIG. 31, the materials of the present description show and describe a procedure 520 for controlling a contactless switching unit and an activation method using compliant material, as described above in connection with FIG. 28A-30. Procedure 520 may be stored in memory 48 and executed by controller 40 according to one embodiment. Procedure 520 begins at step 522 to process the largest or maximum signal path, which is the maximum signal path associated with proximity switches. At step 524, the maximum signal path is input to the controller. Then, at decision block 526, procedure 520 determines whether the current state is set to the standby state and, if so, proceeds to decision block 528 to determine if the maximum signal path is larger than the threshold value. If the maximum signal path is not greater than the threshold value, procedure 520 ends at step 530. If the maximum signal path is greater than the threshold value, procedure 520 proceeds to set the state to the search state at step 532 before ending at step 530.

Returning to decision block 526, if the state is set to the idle state, procedure 520 proceeds to decision block 534 to determine whether the state is set to the search state, and if so, proceeds to decision block 536 to determine whether the maximum signal path is less than the threshold value. If the maximum signal path is less than the threshold value, procedure 520 proceeds to step 538 to set the state to the standby state, and then ends at step 530. If the maximum signal path is not less than the threshold value 536, procedure 520 proceeds to decision block 540 to determine whether all signal paths are stable, and if not, ends in step 530. If all signal paths are stable, procedure 520 proceeds to step 542 to set the state of nym of a virtual button, and then, sets the channel base at the maximum of the signal channel in step 544 before ending at step 530.

Returning to decision block 534, if the state is not set equal to the search state, procedure 520 proceeds to decision block 546 to determine whether the state is in the state of the virtual button, and if not, proceeds to block 548 to set the state to state button clicks. After that, procedure 520 proceeds to decision block 550 to determine if the maximum signal path is smaller than the threshold value, and if not, ends in step 530. If the maximum channel is less than the threshold value, procedure 520 sets the state equal to the wait state at step 522, and then resets activation at step 554 before ending at step 530.

Returning to decision block 546, if the state is set equal to the state of the virtual button, procedure 520 proceeds to decision block 556 to determine if the maximum signal path is smaller than the threshold value, and if so, sets the state to the idle state at step 558, before ending at step 530. If the maximum signal path is not less than the threshold value, procedure 520 proceeds to decision block 560 to determine if the timer is a virtual kn the flashing is larger than the timeout, and if so, sets the state to the search state at step 562 before ending at step 530. The virtual button timer can be set in the range of one to three seconds according to one embodiment. If the virtual button timer does not exceed the timeout, procedure 520 proceeds to decision block 564 to determine whether all signal paths are stable, and if not, ends in step 530. If all signal paths are determined to be stable, procedure 520 proceeds to step A decision 566 to determine whether a rubber domed button element is pressed, which may be determined by a maximum signal path, greater than the base of the signal path, summed with the value of the dome delta signal button element. If the rubber domed button element is pressed, decision 520 proceeds to decision block 568 to set the state to the state of the pressed button, and then forms the activation of the maximum signal path at step 570 before ending at step 530. If the rubber domed button element is not pressed , procedure 520 proceeds to step 572 to determine that the finger is still slipping and to update the base ChBase signal with the maximum signal path in step 572 before ending at step 530.

Accordingly, the non-contact switching unit 20 having compliant material 500 and the virtual button mode advantageously provides for detecting the activation of the virtual button switch to improve the rejection of unintentional activations. Method 520 can advantageously detect activation of a switch, while deviation of a switch with inadvertent activation can be detected when a finger gropes for a switch assembly. Improved activation detection predominantly provides an improved contactless switching unit, which can be particularly beneficial and useful in automotive applications where driver distraction can be avoided.

The non-contact switching unit 20 may include a rigid substrate having a first, upper surface and a second, lower surface, a non-contact sensor located on the substrate, pliable material located on the upper surface of the substrate, and a recess formed in the upper surface of the substrate in the region between the compliant material and a proximity sensor, according to one embodiment. The recess is generally larger in size than the non-contact sensor, so that the recess is longer and wider than the non-contact sensor. The recess provides an opportunity for the formation of an air gap between the compliant material and the proximity sensor.

With reference to FIG. 32-34D, a contactless switching assembly 20 is illustrated using compliant material 500 covering a rigid substrate 12 and recesses 600 formed in the upper surface of the substrate 12 according to one embodiment. The non-contact switching unit 20 includes a rigid substrate 12, generally shown as a flat sheet material having first and second surfaces, shown as upper and lower surfaces. The first and second proximity sensors 24, such as capacitive sensors, are shown located on the lower surface of the substrate 12, each of which generates an excitation field for the corresponding proximity switch 22. It should be appreciated that one or more proximity sensors 24 may be included, each sensor produces an excitation field. Contactless sensors 24 are shown provided on the bottom surface of a rigid substrate 12, such as a polymer console 12 above a windshield, according to one embodiment. Each of the proximity sensors 24 can be formed by printing conductive printing ink on the bottom surface of the rigid substrate 12. The proximity sensors 24 can be formed differently, for example, by mounting preformed conductive traces of the circuit on the substrate 12 according to other embodiments.

A pliable material 500 is shown covering the substrate 12 and is intended to provide a touch surface for the user's finger 34 to interact with one or more of the proximity sensors 24 to activate one or more of the proximity switches 22. The pliable material 500 may be formed as a cover layer, which can be made of an elastic material, including rubber, according to one embodiment. The pliable material 500 is relatively flexible with respect to the underlying substrate 12, which is typically rigid. The compliant material 500 covers the proximity sensors 24 and is deformable when the user's finger applies pressure, so that the finger 34 compresses the compliant material 500 and moves toward the proximity sensor 24. The compliant material 500 may have a thickness as described above in connection with other embodiments, such as in the range of 0.1 to 10 millimeters, and more preferably in the range of 1.0 to 2.0 millimeters.

The non-contact switching unit 20 further includes a recess 600 in the upper surface of the rigid substrate 12 in the region between the compliant material 500 and each non-contact sensor 24. Separate recesses 600 may be formed in the upper surface of the substrate 12, each typically close to one of the non-contact sensors 24. The recess 600 has a length and width that are larger than the non-contact sensor 24. The relative size of the recess 600 relative to the non-contact sensor 24 is illustrated in phi g. 33. The recess 600 has a first length L _D compared to the proximity sensor 24, which has a second length L _S , wherein the first length L _D is at least 5 millimeters longer than the second length L _S , according to one embodiment. According to a more specific embodiment, the first length L _D exceeds the second length L _S by a distance in the range of 5 to 10 millimeters. The recess 600 also has a width W _D that is greater than the width W _{S of the} proximity sensor 24. The width W _D may exceed the width W _S by at least 5 millimeters according to one embodiment, and more specifically, a distance in the range of 5 up to 10 millimeters. The recess 600 may have a thickness in the range from 0.5 to 2.0 millimeters according to one embodiment.

Although the proximity switch assembly 20 is shown and described herein having each proximity sensor 24 and a recess 600 formed in a rectangular shape, it should be appreciated that the sensor 24 and the recess 600 may include other shapes and sizes, such as round shape or other shape. When acted in this way, the recess 600 has a depth and, moreover, has an overall dimension of length and / or width that is larger than the size of the length and / or width of the proximity sensor 24 closest to it. With respect to the proximity sensor 24 and the round recess 600, the size may be a measurement of the diameter of the round shape for each of the sensor 24 and the recess 600, while the size of the recess 600 is larger than the size of the contactless sensor 24 by at least 5 millimeters, according to one embodiment, more specifically, in the range of 5 to 10 millimeters.

According to one embodiment, the recess 600 formed in the rigid substrate 12 provides a space for an air gap to be formed between the lower surface of the recess 600 of the substrate 12 and the covering pliable material 500. The air gap formed in the recess 600 provides a space so that the user's finger pressed the malleable material 500 in close proximity with the proximity sensor 24. Despite the fact that the air gap is shown and described in the materials of this op tangency as filling space in the recess 600, it should be appreciated that other material such as a liquid or other gas, can be disposed therein. In addition, it should be appreciated that a soft pliable material may be located in the recess 600, the material being substantially less rigid than the rigid substrate 12.

The contactless switching unit 20 can additionally apply a control circuit to control the field of excitation associated with each proximity sensor 24, and to determine the activation of the corresponding proximity switch 22 based on the signal generated by the proximity sensor 24, relative to the threshold value when the user's finger 34 presses a compliant material 500 V recess 600. The signal, as a rule, increases the amplitude when the user's finger moves closer to the proximity sensor 24. The control circuit can t operate as described above in connection with the embodiments shown in FIGS. 28A-31.

With reference to FIG. 34A-34D, the proximity switch assembly 20 is illustrated using a compliant material 500 covering a recess 600 on top of each of the proximity sensors 24 according to the first embodiment. As seen in FIG. 34A, the user's finger 34 is shown in a first position in contact with the upper surface of the compliant material 500 at a location close to, but laterally offset from, the proximity sensor 24 and the recess 600. FIG. 34B, the user's finger 34 is shown to be sliding in a second position centered on top of the proximity sensor 24 and recess 600 without applying force or pressure to the compliant material 500. This may occur when the user gropes the proximity switching unit 20 in the grope / search mode without of any intention to activate the proximity switch 22. FIG. 34C, the user's finger 34 is shown applying force to the proximity sensor 24 to press the compliant material 500 to move the user finger 34 to a third position, closer to the proximity sensor 24 to compress the flexible material 500 and to squeeze the air gap provided in the recess 600, and, in addition, flatten and, thereby, smooth the finger on the substrate 12 in the lower part of the recess 600, in order to provide an increase in the surface area or volume of the finger in close proximity to the sensor 24, which gives a greater interaction ystvie associated with the excitation field, and hence, a larger signal.

The sequence of events shown in FIG. 34A-34C is further illustrated in the response of signal 606 shown in FIG. 34D. The signal 606 generated by the proximity switch 24 is shown rising to a first level 606A, indicating a user's finger 34 in contact with the proximity switch unit 20 in a first position transversely distant from the proximity sensor 24, as seen in FIG. 34A. Signal 606 maintains the amplitude of the signal at 606B, indicating the user's finger 34, shown in a second position aligned with the proximity sensor 24 and recess 600, without applying force, as shown in FIG. 34B. Thereafter, the signal 606 then rises to a third elevated level 606C indicating a user finger applying force in the third position to press the pliable material 500 into the recess 600, as shown in FIG. 34C. Thus, the signal 606 is much larger when the user's finger 34 presses the compliant material 500 into the recess 600, which enables improved switch detection. The control circuit, in this case, can control the field of excitation and the signal 606 and determine the activation of the proximity switch 22 based on the signal 606, as described in the materials of the present description.

The contactless switching assembly 20 may be formed with one or more grooves formed in a rigid substrate between the first and second contactless sensors, as shown in FIG. 35-37E, according to another embodiment. In this embodiment, a single groove 610 is shown located between adjacent proximity sensors 24 to provide isolation of signals between adjacent proximity sensors 24. It will be appreciated that one or a plurality of grooves may be formed in the rigid substrate 12 between adjacent proximity sensors 24. In this embodiment, groove 610 may be used in combination with recesses 600 or may be used without recesses 600. By applying a combination of recesses 600 and groove 610, improved signal detection and reduced signal interference can be achieved. By employing a groove 610 without recesses 600, a more compact proximity switch assembly 20 can be achieved with proximity switches 22 located close to each other without oversized recesses.

As seen in FIG. 35 and 36, a groove 610 is shown formed on the upper surface of the rigid substrate 12 in the region between the first and second proximity sensors 24. The groove 610 may have a first size shown as a length L _G that is at least as long as W _S , the width of the sensor 24, or at least as long as W _D in the embodiment with a recess 600, and preferably 5 to 10 millimeters wider than the width W _S , or 0 to 5 millimeters larger than W _D in the embodiment with the recess 600 and the second resolution shown As the width W _G in the range 1 millimeter to 5 millimeters. The depth of the groove 610 may range from 0.5 to 2.0 millimeters. It will be appreciated that the depth of the groove 610 may extend a substantial distance into the upper surface of the rigid substrate 12. In one embodiment, the rigid substrate 12 is made of plastic. Groove 610 forms an air gap therein. The air gap has a low dielectric constant, which effectively attenuates the field of excitation in that region and reduces or prevents crosstalk or mutual influence of signals.

With reference to FIG. 37A-37E, the contactless switching assembly 20 is illustrated using a compliant material 500, recesses 600, and a groove 610 according to one embodiment. As seen in FIG. 37A, the user's finger 34 shown in the first position is in contact with the surface of the compliant material 500 at a location close to but transversely offset from the proximity sensor 24. In FIG. 37B, the user's finger 34 is shown to move, sliding to a second position aligned with the first proximity sensor 24, without applying force or pressure to the compliant material 500. This may occur when the user gropes the proximity switch unit 20 in the grope / search mode without the intention of activating the proximity switch 22. In FIG. 37C, a user finger 34 is shown moving by sliding laterally over the groove 610 to a third position aligned with the second proximity sensor without applying force or pressure to the compliant material 50, for example, as might occur in the groping / searching mode. In FIG. 37D, a user finger 34 is shown sliding further into a fourth position in the region of the second proximity sensor 34. It will be appreciated that the user may press the compliant material 500 over any of the first or second proximity sensors 24 to activate the first or second proximity switches 22.

The sequence of events shown in FIG. 37A-37D is further illustrated in the responses of the first and second signals 608 and 609 shown in FIG. 37E. The first signal 608 generated by the first proximity sensor 24 is shown at the first level 608A when the user's finger is in contact with the contactless switching unit 20 in both the first and second positions, as seen in FIG. 37A and 37B. As the user's finger approaches the groove 610 between the first and second proximity sensors, the first signal 608 drops to a lower or zero value. The second signal 609 generated by the second proximity sensor 24 rises back to the signal level 608C and 608D when the user's finger moves further from the groove 610 and approaches the third and fourth positions, as shown in FIG. 37C and 37D. The signals 608 and 609, which are at a reduced or zero value, occur when the user's finger 34 passes the groove 610 between the first and second proximity sensors 24. The groove 610 effectively isolates the signals 608 and 609 to lower the signal to a lower or zero value and thereby preventing mutual influence between adjacent proximity sensors 24. The control circuit, therefore, can determine the activation of the first and second switches 22 based on signals 608 and 609 with reduced mutual influence signals.

Additionally, a non-contact switching unit 20 is configured with a compliant material 500 having a convex or protruding touch surface portion 620 aligned with each of the non-contact sensors 24 and recesses 500, as shown in FIG. 38, according to a further embodiment. In this embodiment, the protruding surface 620 provides an increased travel distance between the activations of the switches, which can also serve as a tactile sensation for the user. The height of the protruding surface 620 may range from 1 to 2 millimeters according to one embodiment. The protruding surface 620 may hold the finger 34 of the user further from the proximity sensor in a non-pressed state. In addition, it should be appreciated that the protruding surface 620 can be used with recesses 600 or with one or more grooves 610, or both with recesses 600 and one or more grooves 610.

Accordingly, a non-contact switching assembly 20 having compliant material 500 may utilize recesses 600 and / or one or more grooves 610 to provide improved signal detection and activation of the switch.

It should be understood that changes and modifications may be made to the above construction without departing from the concepts of the present invention, and in addition, it should be understood that such concepts are intended to be covered by the following claims, unless the claims expressly state otherwise in their own language.

Claims (27)

1. Non-contact switching node containing: a rigid substrate having upper and lower surfaces and a recess in the upper surface of the substrate; a proximity sensor containing the first and second electrodes located on the substrate below the recess; non-conductive ductile material provided on the upper surface of the substrate and extending above the recess; in this case, the proximity sensor generates an output signal indicating the dielectric properties of the user's finger. 2. The non-contact switching unit according to claim 1, wherein the recess has a first length and the non-contact sensor has a second length, the first length being at least 5 millimeters longer than the second length. 3. The non-contact switching unit according to claim 2, wherein the first length exceeds the second length in the range of 5 to 10 millimeters. 4. The non-contact switching unit according to claim 1, wherein the recess has a thickness in the range from 0.5 to 2.0 millimeters. 5. The non-contact switching unit according to claim 1, wherein the ductile material is rubber. 6. The non-contact switching unit according to claim 1, wherein the air gap is formed in the recess. 7. The non-contact switching unit according to claim 1, wherein the non-contact sensor is located on the lower surface of the substrate. 8. The non-contact switching unit according to claim 1, further comprising a control circuit that controls the excitation field associated with the non-contact sensor and determines the activation of the non-contact switch based on the output signal generated by the sensor relative to the threshold value when the user's finger presses compliant material. 9. The contactless switching assembly of claim 1, wherein the assembly comprises a plurality of proximity switches, each of the proximity switches comprising a proximity sensor formed on a lower surface of the substrate, and a recess formed on the upper surface of the substrate, and at least one groove extending into substrate between adjacent proximity switches. 10. The non-contact switching unit according to claim 1, comprising a capacitive switch comprising one or more capacitive sensors. 11. The non-contact switching unit according to claim 1, installed in the vehicle. 12. The non-contact switching unit according to claim 1, wherein the compliant material comprises a protruding portion located above the recess. 13. A non-contact switching unit of a vehicle, comprising: a rigid substrate having a first and second surface, and a recess forming an air gap in the second surface of the substrate; a proximity sensor comprising first and second electrodes located on the first surface of the substrate below the recess; and non-conductive malleable material provided on the second surface of the substrate and continuing above the recess; wherein the recess is longer than the proximity sensor, wherein the proximity sensor generates an output signal indicative of the dielectric properties of the user's finger. 14. The non-contact switching unit according to claim 13, wherein the recess has a first length and the non-contact sensor has a second length, the first length being at least 5 millimeters longer than the second length. 15. The non-contact switching unit according to claim 14, wherein the first length exceeds the second length in a range of 5 to 10 millimeters. 16. The non-contact switching unit according to claim 13, wherein the recess has a thickness in the range of 0.5 to 2.0 millimeters. 17. The non-contact switching unit according to claim 13, wherein the ductile material is rubber. 18. The proximity switch assembly of claim 13, wherein the proximity switch is a capacitive switch comprising one or more capacitive sensors. 19. The non-contact switching unit according to claim 13, wherein the pliable material comprises a protruding portion located above the recess. 20. The proximity switch assembly of claim 13, comprising a plurality of proximity switches, each of which comprises a proximity sensor formed on a lower surface of the substrate, and a recess formed on the upper surface of the substrate, and at least one groove extending into the substrate between adjacent non-contact switches.

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