CA1250654A - Acoustic switch - Google Patents

Acoustic switch

Info

Publication number
CA1250654A
CA1250654A CA000489456A CA489456A CA1250654A CA 1250654 A CA1250654 A CA 1250654A CA 000489456 A CA000489456 A CA 000489456A CA 489456 A CA489456 A CA 489456A CA 1250654 A CA1250654 A CA 1250654A
Authority
CA
Canada
Prior art keywords
flip
flop
output
coupled
switch
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
CA000489456A
Other languages
French (fr)
Inventor
Peter Liljequist
Kou I. Chen
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Joseph Enterprises Inc
Original Assignee
Joseph Enterprises Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority to US75953485A priority Critical
Priority to US759,534 priority
Application filed by Joseph Enterprises Inc filed Critical Joseph Enterprises Inc
Application granted granted Critical
Publication of CA1250654A publication Critical patent/CA1250654A/en
Application status is Expired legal-status Critical

Links

Abstract

ACOUSTIC SWITCH
ABSTRACT OF THE DISCLOSURE
The present invention is a light indicator for an acoustic switch which is connected so that this single indicator will produce a light only when both A/C power is supplied to the switch and an appliance is plugged into the switch and turned on ready to receive power. The switch has a microphone which produces an electrical signal when sound is detected. This elec-trical signal is supplied to an activating circuit which will activate a trigger device to couple the A/C line power to the connected appliance.

Description

00291-2/PPPPPl ACOUSTIC SWITCH

Acoustic switches are used to replace manually operated on-off switches such as light switches or switches for other household appliances. Acoustic switches are triggered by the presence or absence ~f sound of a particular t~p~. For instance, U.S. Patent 3,949,366 to Spillar, et al., discloses a system for turning on and off appliances which is activated by a fixed frequency of~sound generated by a transmitter.
Another system shown in U.S. Patent 4,408,308 to Smith, _ al., shows a switch which automatically turns off in the event that no sound is detected for a fixed period of time. This type of switch is useful for turning off lights or o~her appliances when people leave a room.

The present invention is a light indicator for an acoustic switch which is connected so that this single indicator will produce a light only when both A/C p~wer is supplied to the switch and an appliance is plugged into the switch and turned on ready to receive power. The switch has a microphone which produces an electrical signal when sound is detected. This elec trical signal is supplied to an activating circuit which will activate a trigger device to couple the A/C line power to the connected appliance.
In the preferred embodiment, the light indi-cator is a combination of a resistance and a light emit-ting diode in series coupled across the tri~gering de-vice. The trigqering device is a triac switch. Four flip flops are used to activate the triac switch when twb closely spaced sounds, such as two hand-claps, are 3S detected.

,i ~D~

The first flip-flop receives an amplified signal from the microphone, causing it to produce a positive output. This output is coupled to the clock input of a second flip-flop and also charge~ a capaci-tor coupled to a data input of ~he second flip flop.
Thus, a first sound will clock the first flip-flop to produce a positive input to the second flip~flop after about ~ half second delay. This delay is the period of time it takes the capacitor to charge. The first flip-flop is then reset after a half second when a capacitor coupled to the reset inport becomes charged. If a~sec-ond sound appears after this reset and before the dis-charge of the capacitor coupled to the input of the second flip-flop, the first flip-flop will be toggled again, thereby clocking an output from the second flip-flop.
The output of the second flip-flop will clock the third and fourth flip-flops, which are connected together to provide sufficient current to turn on the triac switch. The data inputs of the third and fourth flip-flops are coupled to the negative output of one of the third and fourth flip-flops. This causes the flip-~lops to change state each time, thereby alternately turning on and off the triac switch.
The indicator light enables a user to deter-mine both ~13 whether the switch is coupled to A/C power and ~2) whether an appliance both plugged into the switch and is turned on. This dual function indicator enables a user to determine at a glance whether the system is in operating condition without requiring a user to check the on/off switch of the appliance itself or the other connections. When a user makes two successi~e sounds, sUch as hand claps, the switch will be activated and the indicator light will turn off, indicating that power has been supplied to the appliance~ This is particu~
la~ly useful for some appliances, such as a television, which take some time to warm up. Without the indicator ,, .

light, a user would not know immediately that he had suc cessfully turned on the television.
The invention also has an amplifier with suf-ficient gain to enable hand claps from as far away as twenty feet to be detected. Since this large amount of gain may also cause background noises to set off a switch, the sensitivity of the switch is user ad~justable.
Preferably~ a resistive potentiometer is connected to the input of the first flip-flop and is user accessible, enabling the user to adjust the sensitivity of the switch.
For a fuller understanding of the nature and advantages of the invention, reference should be made to the ensuing detailed description taken in conjunction with the accompanying drawing, which is a schematic view of a preferred embodiment of the present invention.

The drawing is a schemakic view of the acoustic switch of the present invention. A/C line power is coupled to a pair of input terminals 10~ An appliance to be switched on and off is connected to a pair of output ter-minals 12. A triac sitch 14 will couple line power to the appliance coupled to output 12. A triggering signal ~or triac 14 is provided through the operation of flip-flops 16, 18, 20, and 22. These flip-flops are enabled by a signal for a microphone 24 which is amplified by a tran-sistor 26. Rectified D/C power for the circuit is provided by a Zener diode 28. A negative grol~nd return is provided through diode 30 and resistors 32, 34, and capacitor 36.
A filter capacitor 38 is coupled across the posi-tive and negative D/G lines. A limiting resistor 40 pro-vides ~/C power to the flip-flops.

'b~

In operation, when microphone 24 detects a sound, it operates to couple the base of transistor 26 to ground. This turns off transistor 26, pulling its collector high and presenting the high signal to the clock input 42 of flip-flop 16. Data input 44 for the flip-flop 16 is always held high by the positive power supply. The size of the signal xe~uired to activate clock input 42 is controlled by potentiometers 46 and 48 in conjunction with resistor S0. Potentiometer 48 is adjusted when the switch is manufactured to compen-sate for differences due to the particular components used. Potentiometer 46 is user accessible, enabling a user to adjust the~sensitivity of the device.
A resistor 52 is provided to perform current limiting for microphone 24. Resistors 54, 56, 58, and 60 are used for biasing transistor 26. Transistor 26 preferably has a gain of approximately 200 Hfe. This provides a sensitivity for audio noises up to a range of approximately twenty feet from the acoustic switch.
Upon receiving a clock signal at input 42, flip~flop 16 will produce a positive output at output 62. This output is coupled to a clock input 64 of flip-~lop 18. However, the first sound to appear will not cause flip-flop 18 to toggle since a data input 66 would normally be low. However, t~is first clock signal will char~e a capacitor 68 through a resistor 70 to give a high level data input for flip-flop 18. This high-level input to clock input 34 will disappear when capacitor 68 discharges after output 62 of flip-flop 16 is reset to zero.
Output 62 of flip-flop 16 will be reset to zero when the high level signal applied across resistor 72 and capacitor 74 charges up capacitor 74 to present a high level input to a reset input 76 of flip-flop 16.
The time constants of capacitors 68 and 74 are chosen so~that two sounds must occur more than one-half second and approximately less than one second apart. The second sound must thus occur after flip-flop 16 has been reset and before the charge on capacitor 68 has decayed sufficiently to eliminate the positive signal at i~put 66 of flip-flop 18. The second sound appearing in this time window will trigger flip-flop 18 giving a positive output on output 78 of flip-flop 18.
When flip-flop 18 has a positive output on output 78, this will trigger clock inputs 80 and 32 of 10 1ip-flops 22 and 20, respectively. Because data inputs 84 and 86 are initially high, both flip-flops will tog-gle, producing a high level output on outputs 88 and 90. These outputs are coupled through resistors 92 and 94, respectively, to the trigger input of triac 1~.
- A low level will appear on the inverse output 96 of flip-flop 22, which is coupled to the data inputs 84 and 86 of flip-flops 22 and 24. Thus, the next set of two successive sounds will produce a low level out-put of flip-flops 20, 22, thereby turning off triac 14.
A resistor 98 and an LED 100 are coupled across triac 14. Current will 10w through resistor 98 and LED 100 only when line power is coupled to inputs 10 and an appliance is coupled to output 12. In addi-~tion, the appliance must be turned on to receive power, thereby enabling current flow. When triac 14 is trig-gered, current will flow through triac 14, thereby by-passing resistor 98 and LED lO0. The light fxom LED
100 will thus disappear, indicating that the appliance has been connected.
As will be understood by those familiar wi~h the art, the present invention can be embodied in other forms without departing from the spixit or essential characteristics thereof. For example, a device other than an LED could be used to provide a light when triac 14 has not been triggered, or another trigger device could be used in place of triac 14. Alternate circuit configurations other than the flip-flops shown could be used to provide the triggering signal to triac 14.

, . ^ . .

~ .

:.

~ C~6~

Accordingly, the foregoing embodiments are intended to be illustrative of, but not limiting of, the scope of the invention, which is set forth in the following claims.

Claims (10)

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:
1. A sound activated switch for coupling a line power source to an appliance connected to an output ter-minal of said switch comprising:
means for detecting a sound and producing an electrical signal in response to said sound;
switch means for coupling said line power source to said output terminal;
triggering means, responsive to said electrical signal, for triggering said switch means; and light indicator means for producing a light signal when both said line power is coupled to said switch and said appliance is coupled to said output terminal in a turned-on state ready to receive line power.
2. The apparatus of claim 1 wherein said switch means comprises a triac switch.
3. The apparatus of claim 1 wherein said light indicator means comprises a series combination of a resistance and a light-emitting diode coupled in parallel with said switch means.
4. The apparatus of claim 1 wherein said means for detecting a sound comprises an electret condenser microphone and an amplifier having a gain of at least 200.
5. The apparatus of claim 1 wherein said triggering means is adapted to be activated by a first level of said electrical signal and further comprising means for adjusting said triggering means so that said triggering means is activated by a second level of said electrical signal, said means for adjusting being user accessible.
6. The apparatus of claim 1 wherein said triggering means includes timing means responsive to said electrical signal occurring twice due to two loud sounds approximately one second apart.
7. The apparatus of claim 6 wherein said triggering circuit comprises:
a first flip-flop being coupled to produce a high-level output signal in response to said electrical signal;
a second flip-flop having a clock input and a data input coupled to receive said first flip-flop output signal;
a capacitor coupled to said data input of said second flip-flop, said capacitor being arranged to be charged to a high level subsequent to said first flip-flop output signal changing to a high level in response to a first loud sound so that said second flip-flop will produce a high-level output signal in response to a second high-level output signal from said first flip-flop; and a third flip-flop having a clock input coupled to receive said output signal of said second flip-flop and having an output;
said switch means comprising a triac having a trigger input coupled to said output of said third flip-flop.
8. The apparatus of claim 7 further comprising a user-adjustable variable resistance coupling a positive power supply to a clock input of said first flip-flop.
9. The apparatus of claim 7 further comprising a second capacitor coupled to said output of said first flip-flop and to a reset input of said first flip-flop, said second capacitor being arranged and adapted to provide a high-level signal to said reset input approximately one-half second after a high level signal appears on said flip-flop output.
10. A sound-activated switch for coupling a line power source to an appliance connected to an output ter-minal of said switch comprising:
an electret condenser microphone;
a transistor amplifier having a gain of at least approximately 200 and being coupled to amplify a signal from said microphone;
a first flip-flop having a clock input, a reset input and an output, a said clock input being coupled to an output of said amplifier;
a first capacitor coupled to said output and said reset input of said first flip-flop, said first capa-citor being arranged and adapted to provide a high-level signal to said reset input approximately one-half second after a high level signal appears on said first flip-flop output;
a variable resistor coupling said first flip-flop clock input to a power supply a second flip-flop having a clock input and a data input coupled to said first flip-flop output;
a second capacitor coupled to said second flip-flop data input, said second capacitor being arranged and adapted to be charged to a high level subsequent to said signal at said first flip-flop output charging to a high level;
a third flip-flop having a clock input coupled to said second flip-flop output, a data input, an output, and an inverse output coupled to said third flip-flop data input;

a triac coupling said line power to said output terminal, said triac having a trigger input cou-pled to said third flip-flop output; and a series combination of a resistance and a light emitting diode coupled in parallel with said triac.
CA000489456A 1985-07-26 1985-08-27 Acoustic switch Expired CA1250654A (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
US75953485A true 1985-07-26 1985-07-26
US759,534 1985-07-26

Publications (1)

Publication Number Publication Date
CA1250654A true CA1250654A (en) 1989-02-28

Family

ID=25056018

Family Applications (1)

Application Number Title Priority Date Filing Date
CA000489456A Expired CA1250654A (en) 1985-07-26 1985-08-27 Acoustic switch

Country Status (1)

Country Link
CA (1) CA1250654A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5493618A (en) * 1993-05-07 1996-02-20 Joseph Enterprises Method and apparatus for activating switches in response to different acoustic signals

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5493618A (en) * 1993-05-07 1996-02-20 Joseph Enterprises Method and apparatus for activating switches in response to different acoustic signals

Also Published As

Publication number Publication date
CA1250654A1 (en)

Similar Documents

Publication Publication Date Title
US4344184A (en) Wireless microphone
US5999089A (en) Alarm system
US6704424B2 (en) Hearing aid with audible alarm
US20010019228A1 (en) Circuit arrangement for a sensor element
US5769120A (en) Infrared sensor with remote control option
US20070290874A1 (en) Touch screen with sensory feedback
US3536836A (en) Acoustically actuated switch
US5212672A (en) Timing control apparatus
EP0262909A2 (en) Touch controlled switching circuit
US4152629A (en) Lamp responsive to the human touch upon a living plant and control system therefor
US4344071A (en) Light switching mechanism
US7855543B2 (en) Force invariant touch sensitive actuator
US4570155A (en) Smoke alarm activated light
US4494012A (en) Switch timer
US5283816A (en) Smoke detector using telephone link
US4289980A (en) Touch sensitive electric switch
US7566996B2 (en) Touch sensitive actuator having a uniform actuation force and a maximum active area
JPH01138813A (en) Level conversion circuit
US3287722A (en) Remote controlled switching system
CA2100110A1 (en) Auditory prosthesis for adaptively filtering selected auditory component by user activation and method for doing same
US3970987A (en) Acoustical switch
US4087702A (en) Digital electronic dimmer
JPH04307896A (en) Output circuit and interface system including this circuit
EP0067502B1 (en) Sound actuated light switch
KR910004438B1 (en) An apparatus which is stopping alarm

Legal Events

Date Code Title Description
MKEX Expiry