GB2388656A

GB2388656A - Swipe switch which brightens or dims according to a count of finger gaps

Info

Publication number: GB2388656A
Application number: GB0207108A
Authority: GB
Inventors: Matthew Paul Michael
Original assignee: Individual
Current assignee: Individual
Priority date: 2002-03-26
Filing date: 2002-03-26
Publication date: 2003-11-19
Anticipated expiration: 2022-03-26
Also published as: GB2388656B; GB0207108D0

Abstract

A non-contact dimmer switch that may be mounted flush with its surroundings is operated by the swiping movement of a hand with fingers apart. The switch comprises an infrared LED emitter and photodiode receiver to detect proximity of a finger, hand direction sensors, a counter and a power supply controller. The counter counts the gaps between the fingers and the controller dims/brightens according to the number of gaps that have passed the switch and the direction the hand passes the switch. The power supply controller does not include a transformer, but has a potential divider circuit, an analogue to decimal converter, a voltage dependant resistor chip, a diac and a triac.

Description

SWIPE DIMMER SWITCH

This invention relates to a swipe switch which dims/brightens the light from a domestic light bulb circuit on each hand swipe.

Swipe switches are well known and mainly used for toilet flush activation, however they suffer from the disadvantages of bulkyness and being either on or off at one time.

The object of the switch is to provide a futuristic switch that is concealed flush in its surrounding (eg:a wall). It will have a dimming circuitry switching and a good ease of use. Current swipe switches usually work on a single pass of a hand or an object; they therefore would find very difficult to have a dimmer switch incorporated into the circuitry. My switch works in a different way, it counts the gaps between the fingers, and uses finger count to accomplish the degree of dimming Most electronic circuits are powered by power supplies containing enormous transformers and bulky components. I have invented a power supply which is part of my switch's circuitry which does away with the traditional transformer and is much smaller therefore, my switch is much smaller and can fit in places where other electronic circuitry would find impossible. (eg: a light switch back box so the switch could be used for electric lighting).

Most lighting switch back boxes have three wires mains Live, Earth and another wire that goes back to the bulb and is indirectly Neutral. My switch uses all three.

Most switches usually protrude from their surroundings (eg:wall). My switch is concealed flush and is less of an eyesore.

A detailed description follows:

As we are dealing with mains all precautions are taken. The circuit is directly behind a thin plastic sheet or screen.

A mark is on the screen just to the left of the sensor. This mark corresponds to the point "only fingers past this point to activate" and the rest of the hand should be kept behind the line to activate.

To activate the switch hold your hand out, palm down towards the screen, with fingers apart and place above the switch and in the air (but near to the switch). See figure 1.

Swipe your hand across the switch (ignoring the thumb) making sure that only your

t fingers cross the line. The light bulb will get brighter for every finger that crosses the sensor. To dim the light, hold your hand out, palm down towards the screen, with fingers apart and place below the switch and in the air (but near to the switch). See figure 2.

Swipe your hand up across the switch (ignoring the thumb) making sure that only your fingers cross the line. The light bulb will get dimmer for every finger that crosses the sensor.

Your hand must be nearer than a "critical distance" from the screen; greater than which the switch will not work. (ie the hand must be close to the plastic screen) After one swipe the hand can be moved away from the switch (more than the critical distance) and a second swipe attempted in a kind of circular motion.

An example of usage would be as a light switch where swiping the switch would dim/brighten the light.

A description of workings follow:

A potential divider (P.D) is made up of the switch circuit as the lower resistor and a high wattage resistor is on the top. This is connected across the mains Live and Earth and a forward conducting rectifier diode is placed in the middle of the P.D. Thus the power supply of the circuit is sorted.

An osolator is made up to produce a pulse of about bus approximately every Sms.

This is fed inline to a infra red LED via a darlington pair transistor arrangement. An infra red photo diode picks up the pulses inverted reflected from the LED when an object is placed infront of the LED and photodiode. This is transistor inverted and amplified and sent to a high pass filter the output of which is rectified and fed to a transistor invertor amplifier, the transistor acts as a comparator not allowing any signals from the filter below approximately 0.7v to pass. The signal is then fed to a negative edge retrigerable monostable with an output pulse of approximately 1 Oms providing an output for approximately 1 Oms longer than an object is placed infront of the LED and photodiode.

The output of the above monostable is fed to a non retrigerable monostable with an output lasting for approximately 7ms for every time the previous monostable is triggered. This output forms the clock of a up/down counter. The counter counts the number of finger gaps.

There are two more photodiodes on either side of the above photodiode. The outputs of the photodiodes are transistor inverted and amplified, sent to a high pass filter and transistor inverted again. Then the signals are sent to bistables. The output of each bistable resets the other. Thus the direction the hand approaches is determined. The output of one of the bistables is fed to the direction pin of the above counter. A negative edge retrigerable monostable with a output pulse of approximately 0.5s resets the bistables and is triggered by the output of the above 7ms monostable.

The output pins of the counter is fed to an analogue to decimal converter the output from which is fed to a voltage dependent resistor chip.

The resistor chip forms the resistor of a C.R. circuit made up of a restor and a capacitor connected across mains (ie the Live and the wire returning to th light bulb).

The junction between the capacitor and the resistor is fed to a diac which is fed to the gate of a triac. The other two triac terminals are connected across mains (ie the Live and the wire returning to th light bulb).

Claims

1. A swipe switch which counts the gaps between the fingers, and gives a lighting circuit brightness according to the number of gaps have passed the switch.

2. A swipe switch as in claim I that switches between dimming and brightening by the direction the hand approaches the switch.

3. A swipe switch as in claim I that has a power supply that does not include a transformer.

4. A swipe switch as in claim I that mounts flush with its surroundings so that it is concealed. 6. A swipe switch substantially as described herein with reference to figure I and the content on the discription sheets.