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Publication numberUS3925708 A
Publication typeGrant
Publication dateDec 9, 1975
Filing dateMar 25, 1974
Priority dateMar 25, 1974
Publication numberUS 3925708 A, US 3925708A, US-A-3925708, US3925708 A, US3925708A
InventorsPicciochi Andrew V
Original AssigneePicciochi Andrew V
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Safety means for audio speakers
US 3925708 A
Abstract
Overload protection circuitry prevents burn out of speakers resulting from an overload due to wattage exceeding the audio speaker or audio speakers capacity. A relay is adapted to automatically disconnect the audio speaker or audio speakers from an audio amplifier's output signal and connect a substitute load across the audio amplifier's output. This relay is adapted to automatically reconnect the audio speaker or audio speakers and disconnect the said substitute load when the audio amplifier's output signal or output wattage again drops to a safe level.
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United States Patent [191 Picciochi [4 Dec.9, 1975 [54] SAFETY MEANS FOR AUDIO SPEAKERS [76] Inventor: Andrew V. Picciochi, 208 Andrews Road, Mineola, NY. 11501 [22] Filed: Mar. 25, 1974 [21] Appl. No.: 454,234

[52] US. Cl 317/13 R; 179/1 A; 317/23;

317/31; 330/207 P [51] Int. Cl. H02H 7/20 [58] Field of Search 317/23, 13 R, 31, 40 A,

317/DIG. 5, DIG. 7, 33 R; 307/130; 330/207 P, 50', 179/1 A, 1 SW, 1 VC [56] References Cited UNITED STATES PATENTS 2,897,270 7/1959 Helpap 179/1 SW 3,205,422 9/1965 Gold 3l7/DIG. 5 3,544,720 12/1970 Corderman 330/207 P Primary Examiner-James D. Trammell Attorney, Agent, or FirmEisenman, Allsopp & Strack ABSTRACT Overload protection circuitry prevents burn out of speakers resulting from an overload due to wattage exceeding the audio speaker or audio speakers capacity. A relay is adapted to automatically disconnect the audio speaker or audio speakers from an audio amplifiers output signal and connect a substitute load across the audio amplifiers output. This relay is adapted to automatically reconnect the audio speaker or audio speakers and disconnect the said substitute load when the audio amplifiers output signal or output wattage again drops to a safe-level.

6 Claiins, 1 Drawing Figure AMP U.S. Patent Dec.9, 1975 3,925,708

'SAFETY MEANS FOR AUDIO SPEAKERS This invention relates to safety means for an audio speaker or audio speaker systems. For instance, when the audio speaker is connected across the output of an audio amplifier, which is capable of delivering more power than the manufacturers recommended for the speaker.

In some cases, the too high audio amplifiers output wattage exceeds the audio speakers wattage capacity causing the audio speaker or audio speakers to burn out. Many musical groups play very loudly and it is quite common for them to exceed the rated wattage of the audio speaker or audio speakers, for instance, an audio speaker or audio speakers connected to, and/or across electric instrument amplifiers, such as, electronic guitar amplifiers. Therefore, there is a need for means to protect the audio speaker or audio speakers from excessive wattage.

It is also desirable to provide the said means by the disconnecting of the audio speaker or audio speakers from the audio amplifiers output signal.

It is also desirable to provide a visual indicator which provides the warning to the players before the audio speaker or audio speakers are disconnected.

It is also desirable to have the said visual indicator provide a warning to the players of the approaching preset wattage rating and/or excessive wattage indicating visually the gradual rise of wattage from the approaching preset wattage rating to the excessive wattage.

It is also desirable to automatically reconnect a disconnected audio speaker or audiospeakers when the output wattage level of the audio amplifier drops to a safe level.

It is also desirable to have a manual over-ride control which permits a player to keep the audio speaker or audio speakers connected even under overload conditions if he wishes to.

It is also desirable to have a substitute load provided across the audio amplifiers output. Some amplifiers need a load when the audio speaker or audio speakers are disconnected.

It is also desirable to have the circuitry of the invention so designed that it will not burn out due to wattage exceeding the wattage rating'of the relay coil or the resistors used therein.

It is also desirable to have the values of the electronic components vary depending on the desired operation of the circuit of this invention. The electronic components which are included in the circuit of this invention govern the operation of the circuit and determine the amount of watts at which the relays tripping action will occur.

Accordingly, a principal object of the invention is to provide new and improved safety means for an audio speaker or audio speakers.

Another object of the invention is to provide new and improved safety means for an audio speaker or audio speakers for effecting the disconnection of the audio speaker or audio speakers from the audio amplifiers output, when the output exceeds .a predetermined level.

Another object of the invention is to provide new and improved safety means for an audio speaker or audio speakers for effecting automatic reconnection of the audio speaker or audio speakers when the audio ampli- 2 fiers output signal or output wattage returns to a safe wattage level following a disconnection.

Another object of the invention is to provide new and improved safety means for an audio speaker or audio speakers having a visual warning to indicate an approaching overload situation, and the gradual rise of wattage from an approaching overload situation to an overload.

Another object of the invention is to provide new and improved safety means for an audio speaker or audio speakers which also prevents damage to an audio amplifier needing a load across its output when the audio speaker or audio speakers are disconnected, by providing a substitute load across the audio amplifiers output.

Another object of the invention is to provide new and improved safety means for an audio speaker or audio speakers having a manual control over-ride to disable the safety means and keep the audio speaker or audio speakers connected even under overload conditions.

Another object of the invention is to provide new and improved safety means for an audio speaker or audio speakers having a visual indicator means for warning of an approaching overload situation and an actual overload even a manual control over-ride has disabled the safety means.

Another object of the invention is to provide new and improved safety means for an audio speaker or audio speakers so designed that the circuitry of the safety means will not burn out due to wattage exceeding the wattage rating of the components therein.

Another object of the invention is to have adjustable values of the electronic components depending on the desired operation of the circuit of this invention. The electronic components which are comprised within the circuit of this invention govern the operation of the circuit and determine the amounts of watts at which the relays tripping action will occur. The electronic components govern the values of the components in their relationship to one another.

The visual warning means illustrated herein are not limited to a single means of visual indication, rather, it can be any indicator means preferred. The relay means illustrated herein are not limited to an absolute number of poles rather, they may be single pole, double pole, triple pole, or any practical number of 'poles depending on the desired wattage capacity of the relay contacts. The contacts will be double throw. The alterations will be made with necessary allowances to achieve the desired operation of the circuit of this invention.

These and other objects will be apparent from the following specification and drawing.

Referring to the drawing, the audio amplifier l, is normally connected to the speaker S, through the relay switch 2', contact 2a, fuse 3, and connection lines 4 and 12. The other connection is made through the common line C. The audio amplifier l is also connected to the relay coil 5, through fuse 7, fixed or variable resistor 6, and switch 13. The other connection is made through the common line C.

The audio amplifier 1 is also connected to neon lamp 9 through fuse 7, and common line C. The neon lamp 9a is optional. When the audio amplifier l, is connected to neon lamp 9a, through resistor 6 and fuse 7, the other connection is made through the common line C and the neon lamp 9, may be omitted from the circuit. The circuit of this invention is adapted to comprise either neon lamp 9, or neon lamp 9a, depending on the desired operation of the circuit of this invention,- It is possible to have neon lamp 9 and neon lamp [9a,tin the circuitof this invention, simultaneously.

' When an overload-situation occurs it is desired to.dis-

connect the speaker S from the audio amplifiers output signal. This is accomplished by the tripping action of the relay and the partings of the relay switch 2, from contact 2a. The relay circuit is comprised of the relay coil 5, connectedthrough resistor 6, and fuse 7, to the hot terminal of the output of the audio amplifier 1. The

relay circuit is completed through the manual control over-ride switch, 13, to the common line C, back to the ground terminal of the audio amplifier l. The resistor 6 is preferably adjustable to preset and adjustthe level on which the relays tripping action will disconnect the normal circuit shown to the speaker S, and determine the ignition of neon lamp 9a. When-breaking the connection with contact 2 1, relay switch 2 swings to the dotted line position making a connection with contact 2b. When the relay switch 2 is in the dotted line position, the speaker S is disconnected from the audio amplifiers output signal and a substitute load resistor 8, is

connected across the output of the audio amplifier l, or

the terminals of theaudio amplifiers output signal.

This is desirable to prevent any damage to, andto provide a load across to the audio amplifier 1.

Neon lamp 9a is connected from thecommon line C to resistor 6, and the relay coil 5 This arrangement allows variable resistor 6 to preset and determine the ignition of thevisual indicator neon lamp 9a. The ignition would be a warning signal activated at a wattage less thanthe wattage that will function the tripping action of the relay. The tripping action in turn set by the fixed or variable resistor 6, the sensitivity of the relay coil, 5, and the snap action of the springing effect.

Assuming an overload situation occurs, thev relay switch 2, will be moved by the relay coil,.from the mally in thefull line position shown and is spring switch 2 is spring loaded in the-dotted line position by means of spring 11, so that there will be a snap action contact 2b,,and resistor 8, which, is connected to the common line C.

. Resistor 8 wattage capacity has a load tolerance which will handle a loadto which it is subjected when contact 2a, to the contact 2b. The relay switch 2 is noreffect and there will not be any undesirableoscillations.

of therelay switch 2..The springing effect is provided so that when the relay switch 2 swings to contact 2b or is automatically being reset, there willnot be any oscillation of the relay switch 2. Other equivalent snap action .relay switches may be used. The springs are not grounded. g i

Fuse 3 and fuse 7 are provided to, protect the safety device, to prevent burn outfrom an overload due to wattage exceeding the relay circuits wattage capacity and provide a means to protect theaudio speakers by preventing burn out from an overload due to wattage exceeding the speakers wattage capacity.

Fuse 7 protects the relay coil 5, and resistor 6, and

neon lamp 9, and/or neon lamp 91 Fuse 3 is a means of protection for the audio speaker S- and the resistor 8. Fuse 7 will blow when the relay circuit issubjected to wattage exceeding its wattage capacity. The blowing of fuse 7 is, the means of opening'the circuit comprised of the relay coil 5, resistor 6, neon lamp 9, and/orneon lamp 9a, and the manual control over-ridelswitch 1 3,

fuse 3. will blow when the wattage exceeds" slightly the said audiospeaker S wattage capacityorslightly iabove the said resistor 8 wattage capacity.'The blowing pf relay switch 2 swings to the dotted line position. Resistor 8'ohmage may be 2, 4, 8 or l6ohms.Resistor 8 may be any ohmage desired depending on the desired operation of the circuit of this invention. The manual control over-ride switch 13 is the means of opening the relay circuit, thus keeping the speaker S connectedv under overload conditions. v

- lcclaim:

1.- An overload protection circuit for an audio speaker system connected to an audio amplifier, in-.

cluding: a

relay means having contacts normally connecting said audio amplifier to said audio speaker system and operative toeffect disconnection when the output power from said audio amplifier exceedsa l predetermined level; and alternate load means connected to said audio amplifier when said audio speaker system is disconnected; the improvement comprising: I impedance means serially connecting the coil of said relay means across saidvaudio amplifier and adjustable for setting the level atwhich the output of said amplifier effects operationof said relay means; and

1, comprising additional indicator ,means directlyshunting said audio amplifier and operative to produce a visual signal when the output of said'amplifierv exceeds the capacity of said speaker system.

' 3'."An overload protection circuit as defined in claim 1, comprising manual override switchingmeans interconnecting the coil of said relay means to said audio amplifier and operative to effect disconnection there'- between, without modifying the operation of said indicator means.

'4. An overload protection circuit as defined in clai 2, comprising manual override switching means interconnecting' the coil of said relay means tosaid audio amplifier and-operative to effect disconnection therebetween, without modifying the operation of' either of 1 said indicator means' v 5. An overload protection circuit as defined in claim 1, wherein said relay means is operative to effect reconnection of said audio amplifier and'said audiospeaker system whenever the output'powe'r from said'audio amplifier descends below said predetermined level.

6.An overloadprotecting circuit as defined in claim l,'including means for permanently disconnecting the coilof said relay means and said-impedance means from said audio amplifier, when the output of said "'Iaudio amplifier exceeds the capacity of said coil and impedance means.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3 925 708 Dated December 9 1975.

Inventor(s) Andrew V. Picciochi It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 1, line 8 After "recommended" insert -wattage Column 2, line 25 After "even" insert -while- Column 2, line 37 Change "amounts" to --amount Signed and Scaled this second Day of March 1976 I [SEAL] A ttes t:

RUTH C. MASON C. MARSHALL DANN Attesting Officer 1 Commissioner oj'latents and Trademarks UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,925,708 Dated December 9, 1975.

Inventor(s) Andrew V. PicCioChi It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 1, line 8 After "recommended" insert wattage- Column 2, line 25 After "even" insert while- Column 2, line 37 Change "amounts" to -amount Signed and Sealed this second Day Of March 1976 Attest:

RUTH C. MASON C. MARSHALL DANN Arresting Officer C Commissioner of Patents and Trademarks

Patent Citations
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US3544720 *Mar 26, 1969Dec 1, 1970Mcintosh Lab IncProtective circuit for loudspeaker
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US4122507 *May 12, 1977Oct 24, 1978Chamberlain Manufacturing CorporationLoudspeaker overload circuit
US4538296 *Jul 22, 1983Aug 27, 1985Short Robert SSound inhibitor for audio transducers
US4759065 *Sep 22, 1986Jul 19, 1988Harman International Industries, IncorporatedAutomotive sound system
US4809338 *Oct 8, 1986Feb 28, 1989Harman International Industries, IncorporatedAutomotive sound system
US5471527Dec 2, 1993Nov 28, 1995Dsc Communications CorporationVoice enhancement system and method
US5548650 *Oct 18, 1994Aug 20, 1996Prince CorporationSpeaker excursion control system
US5751818 *Sep 5, 1996May 12, 1998Audio Authority CorporationCircuit system for switching loudspeakers
US6201680Feb 2, 1999Mar 13, 2001Aram Armen TokatianAdjustable high-speed audio transducer protection circuit
US6351544Dec 10, 1999Feb 26, 2002Harman International Industries IncorporatedRegressively hinged spider
US6647120Apr 1, 2002Nov 11, 2003Community Light And Sound, Inc.Loudspeaker protection circuit responsive to temperature of loudspeaker driver mechanism
US6665415Sep 9, 1999Dec 16, 2003Harman International Industries, IncorporatedLoudspeaker overcurrent protection
US7555410Jul 27, 2006Jun 30, 2009Freescale Semiconductor, Inc.Circuit for use with multifunction handheld device with video functionality
Classifications
U.S. Classification361/102, 330/207.00P, 381/55, 361/71
International ClassificationH02H3/04, H04R3/00, H02H3/02
Cooperative ClassificationH02H3/04, H04R3/007
European ClassificationH02H3/04, H04R3/00C