US3018683A

US3018683A - Audio signal-responsive device

Info

Publication number: US3018683A
Application number: US13325A
Authority: US
Inventors: Frederick L Way
Original assignee: Mobilcolor Inc
Current assignee: Mobilcolor Inc
Priority date: 1960-03-07
Filing date: 1960-03-07
Publication date: 1962-01-30
Anticipated expiration: 1979-01-30

Description

Jan. 30, 1962 F. L. wAY

AUDIO SIGNAL-RESPONSIVE DEVICE Filed March 7, 1960 @www w his ATTORNEYS spines-s trated. This actuator comprises a moving coil transducer 41 of the same general type utilized in conventional loud speakers having a magnet element d2, which may be either an electro-magnet or a permanent magnet, a central pole piece 43 projecting axially from one end of the magnet and another U-shaped pole piece 44 extending from the opposite end of the magnet and having poles d5, 46 on opposite sides of the pole piece d3. A coil member 47 slidably supported for relative axial motion on the pole piece 43 has two lead Wires 43 and 49 which are connected to receive the audio signals passed by the

corresponding lter

13, 14, or 15, a diode rectifier element Si) being inserted in one of these lead Wires. As a result, the coil member 47 is driven axially on the pole member 43 by a force proportional to the amplitude of the audio signal. To transmit axial motion of the coil member 47 a shaft 51 is supported from the coil by a spider S2, the shaft S1 being connected to the actuator member 16a, 17a, or 18a' of FIG. l.

Another form of actuator shown in FIG. 3 utilizes a f structure similar to the usual type of meter movement wherein a coil member 53 is rotatably supported between the spaced ends of two

adjacent pole pieces

54 and 55 of a magnet 56. Two lead Wires 57 and 58, one including a diode rectifier element 59, supply the audio signal to the coil member l53. Consequently, the coil is rotated by a force having a magnitude proportional to the amplitude of the audio signal so that an arm 6@ carrying a pivotally mounted shaft 61 transmits the coil motion to drive the actuator member 16a, 17a, or 18a of FIG. l longitudinally in proportion to the input signal level.

In FIG. 4 a typical step-switched impedance for use in the system of FIG. l is illustrated. This device comprises a series of resilient Contact ingers 62-68 supported in closely spaced parallel relation and carrying adjacent contact elements @which may be small silver blocks, for example. Preferably, one end of each of the fingers is embedded in a support member 70 while the other end rests against the inclined side 71 of a wedge block 72, the fingers in the series having progressively greater length so that they normally are held in spaced parallel relation by the wedge block. An actuator element 74, which is connected to a corresponding actuator member 16a, 17a, or 18a of FIG. l, rests against the outer side of the contact element 69 of the shortest linger 65 so that the resilience of the linger provides a restoring force for the element 74, the actuator member, and the moving coil of the actuating device. ln a typical case, the resilience of the iingers is selected to provide a total restoring force of about fifteen grams when the actuator element 74 has moved suiciently to close all the contacts and the spacing between the contact elements is arranged so that the total travel of the actuator is approximately one-eighth inch.

Connected between each adjacent pair of fingers 62-63 is an impedance elementv which may be one of a group of resistors 75-79 or may comprise the winding 37 of an actuating solenoid of the type described above which, as shown in FIGS. 1 and 4, is joined to the fingers through conductors Si) and 81 and the

lead wires

38, 39, or dit. Accordingly, the individual impedance elements in the group are shunted out successively as the actuator element 74 moves in response to signals or increasing amplitude.

At one end of the series of elements 75-79 a lead Wire 82 is connected to one of the power lines 28, shown in HG. l, while a conductor S3 at the other end or" the series leads to the lamp Z5, 26, or 27, thus connecting all the impedance elements in series with the lamp. Although only seven resilient fingers form the step switch illustrated in FlG. 4 and the impedance comprises but six separate elements, it will be readily apparent that any number of impedance elements may be utilized if the number of resilient fingers is correspondingly increased.

In order to provide an immediate response to switch actuation the total series impedance ofthe elements 75-79 and the actuating solenoid 37 is selected to maintain the corresponding lamp at an operating level just below that suflicient to cast a perceptible amount of light through its color filter onto the object 30 when power is applied and none of the contacts 69 is closed. Moreover, the values of the various impedance elements are selected in accordance with the characteristics of the lamp to decrease the series impedance as the corresponding contacts are closed by the amounts necessary to generate uniform changes in light intensities at all operating levels. For a volt, 150 watt lamp transmitting light through a typical blue filter, the total series impedance required is about 600 ohms and the individual impedance elements in a twenty-element group should have values in `decreasing progression from about 100 ohms for the first element shunted, 90 ohms for the next element shunted, and so on down to about 4 ohms for the last element in the series. The precise impedance values required to provide uniform steps for any specific light source can be readily determined from a graph of light intensity of the desired color plotted against irnpedance in series with the lamp. Also, inasmuch as conventional incandescent lamps produce a relatively high proportion of 'green light and an even higher proportion of red light as compared with the blue light, a 40 watt lamp may be used as the red light source and a 75 watt lamp for the green light source where the blue light source is a watt lamp.

In operation, audio signals from the source 18 are divided into three separate channels according to frequency by the

filters

13, 14, and 15. In each channel the amplitude-

sensitive actuator

16, 17, or 18 moves its actuating member 16a, 17a, or 18a in accordance with the amplitude level of the signals within the corresponding frequency range and this motion is transmitted to the actuator element 74 (FIG. 4) of the corresponding stepswitched impedance device. Because the resilience of the finger elements `6..-63 provides mechanical damping for the actuator unit, the system responds only to changes in amplitude level and not to each cycle of oscillation of the audio signals.

in response to actuator element motion the impedance elements 75-79 of the impedance device are shunted successively by the contacts 69 in accordance with increases in the amplitude of the audio signal, thereby decreasing the total impedance in series with the

lamp

2S, 26, or 27. At the same time, current passing to the lamp through the impedance elements liows through the solenoid winding 37, actuating the arms of the animated object 30 of FIG. 1 for as long as the contacts on the fingers @i and 65 remain separated. When these contacts close as the signal amplitude increases, the solenoid is de-energized, moving the arms to their inactive position, while the reverse motion takes place when the contacts open on decreasing signal amplitude. In this way, the system provides an accurate and complete visible representation of the quality and intensity of variations in audio signal levels.

Although the invention has been described herein with reference to specific embodiments, many modifications and variations therein will occur readily to those skilled in the art. Accordingly, such variations and modications are included within the intended scope of the invention as defined by the following claims.

I claim:

l. A device for producing high fidelity visual representations of audio signals comprising electric light source means, circuit means for connecting the light source means to an electrical energy source, impedance means connected in series with the light source means having a value selected to maintain the light source means at a threshold operating condition, mechanical switch means for reducing the impedance of the impedance means in selected steps to provide substantially uniform changes in light intensity, and electromechanical actuator means com` prising fixed magnet means, coil means supported for oscillatory motion in the magnetic field of the fixed magnet means connected to an audio signal input, and linking means mechanically linking the coil means to the switch means, to activate the switch means in accordance with changes in audio signal amplitude.

2. A device for producing yhigh fidelity visual represen tations of audio signals comprising a plurality of electric light source means, color filter means for each light source means transmitting light rays of a selected color, circuit means for connecting each light source means to an electrical energy source, impedance means connected in series with each light source means having a value selected to maintain the light source means at a threshold operating condition, mechanical switch means for each impedance means for reducing the impedance in selected steps to provide substantially uniform changes in light intensity, electromechanical actuator means for each switch means comprising fixed magnet means, coil means supported for oscillatory motion in the magnetic field of the fixed magnet means connected to an audio signal input, and linking means mechanically linking the coil means to the switch means, to actuate the switch means in accordance with changes in audio signal amplitude, and a plurality of electrical filter means each connected to one of the actuator means and adapted to transmit a selected audio frequency range thereto from an audio signal source.

3. A device for producing high fidelity visual representations of audio signals comprising electric light source means, circuit means for connecting the light source means to an electrical energy source, impedance means connected in series with the light source means having a value selected to maintain the light Source means at a threshold operating condition, mechanical switch means comprising a plurality of spaced resilient conducting members electrically connected to selected points in the impedance means to shunt the impedance means in predetermined steps when adjacent conducting members are joined, the points being selected in accordance with the operating characteristics of the light source means to provide substantially uniform changes in light intensity as the resilient elements are joined successively, and electromechanical actuator means comprising fixed magnet means, coil means supported for oscillatory motion in the magnetic field of the fixed magnet means connected to an audio signal input, and linking means mechanically linking the coil means to the switch means, to actuate the switch means in accordance with changes in audio signal amplitude.

4. A device according to claim 3 wherein the linking means comprises shaft means longitudinally movable in response to coil motion to displace the resilient conducting members laterally and urge adjacent members successively into contact.

5. A device according to claim l wherein the magnet means includes a longitudinal pole piece and the coil means is movable longitudinally on the pole piece.

6. A device according to claim l wherein the magnet means includes a pair of opposed pole pieces and the coil means is rotatably supported between the pole pieces and carries an arm pivotally linked to the linking means.

7. A device according to claim 3 including an object y having a movable me-mber actuatable by electromechanical drive means, and electromechanical means for operating the movable member having a selected electrical impedance connected to form a portion of the impedance means.

8. A device according to claim 7 wherein the object is positioned to be illuminated by the light source means.

9. A device for producing high fidelity visual representations of audio signals comprising a plurality of electric light source means, color filter means for each light source means transmitting light rays of a selected color, circuit means for connecting each light source means to an electrical energy source, a plurality of electrical impedance elements of progressively decreasing value connected in series with each light source means and having a total impedance selected to maintain the light source means at a threshold operating condition, mechanical switch means for each plurality of impedance elements comprising a plurality of spaced resilient conducting members electrically connected to the junctions between adjacent impedance elements in the series to shunt the elements in sequence when adjacent conducting members are joined,

electromechanical actuator means for each switch means comprising fixed magnet means, coil means supported for oscillatory motionkin the magnetic field of the fixed magnet means connected to an audio signal input, and linking means mechanically linking the coil means to the switch means, to join the resilient fingers successively to shunt the corresponding impedance elements, starting with the element having the highest value, and a plurality of electrical filter means each transmitting selected portions of the audio frequency range to one of the actuator means.

10. A device according to claim 9 including an object having a movable member, and solenoid means for actuating the movable member having a winding constituting one of the impedance elements in one of the pluralities of impedance elements.

References Cited in the file of this rpatent rUNITED STATES PATENTS 1,714,504 Greenwalt May 28, 1929 1,977,997 Patterson Oct. 23, 1934 2,246,301 Hanna et al. June 17, 1941 2,275,283 Burchfield Mar. 3, 1942 2,717,351 Christian et al. Sept. 6,y 1955