ELECTRONIC ARRANGEMENT FOR SIMULATING ANIMAL SOUNDS
United States Patent 3594786
An electronic arrangement for simulating sounds emitted by animals. A clock ulse generator transmits pulses which are partially differentiated and/or integrated. The resulting pulse signals are applied to a series of astable multivibrator circuits which synthesize audiofrequency signals representing the various types of animal cries. Multivibrator circuits may be combined with each other in a particular arrangement, and these combinations may be operated in conjunction with variable integrating and differentiating circuits to produce the desired results. Loud speakers powered by amplifiers emit in audible form the signals provided and processed by the multivibrators.
US Patent References:
Electronic sirens
Keeling - June 1964 - 3137846

High-pitched horn
Monomakhoff - December 1964 - 3160877

Sound producer
Borsattino et al. - November 1966 - 3284796

Cow bell instrument
Park - June 1967 - 3325578


Inventors:
Brunner-schwer, Hans G. (Villingen/Black Forest, DT)
Schulz, Hansrichard (Villingen/Black Forest, DT)
Bulow, Joachim (Villingen/Black Forest, DT)
Application Number:
04/734845
Publication Date:
07/20/1971
Filing Date:
06/04/1968
View Patent Images:
Assignee:
Saba Schwarzwalder Apparate-Bau-Anstalt August Schwer Sohne GmbH (Villingen am Black Forest, DT)
Primary Class:
International Classes:
A01M29/02; G09B15/00; A01M29/00; G08B3/00
Field of Search:
340/384E
Primary Examiner:
Caldwell, John W.
Assistant Examiner:
Slobasky, Michael
Claims:
We claim

1. In a device for simulating animal sounds, a combination including pulse controlled signal generator means emitting signals within the frequency range of animal sounds, said signal generating means comprising a first multivibrator circuit, a second multivibrator circuit connected to said first multivibrator circuit and amplitude modulated by said first multivibrator circuit, and a third multivibrator circuit connected to said second multivibrator circuit for frequency modulating said second multivibrator circuit; clock pulse generator means connected to said signal generator means for controlling, by a train of pulses applied to said signal generator means, the frequency of repetition of the simulated animal sounds; integrating means connected to said pulse generator means for shaping the pulses applied to said signal generator means to cause the output of the latter to fall in frequency during the interval of each pulse from said pulse generator means; and variable integration means connected to said signal generator means for obtaining the desired frequency variation of the output of said signal generator means during each said interval.

2. A combination as defined in claim 1, wherein said first multivibrator circuit and said second multivibrator each comprises a discrete said variable integration means.

3. In a device for simulating animal sounds, a combination including pulse controlled signal generator means emitting signals within the frequency range of animal sounds; clock pulse generator means connected to said signal generator means for controlling, by a train of pulses applied to said signal generator means, the frequency of repetition of the simulated animal sounds; multivibrator circuit means connected to said clock pulse generator means for emitting rectangular pulses; low pass filter means connected to said multivibrator circuit means and filtering the fundamental wave from said rectangular pulse signals; rectifier means connected to said low pass filter means for attenuating said fundamental wave; and band pass filter means connected to said rectifier means for passing a predetermined frequency spectrum to provide a predetermined timbre.

4. A combination as defined in claim 3, wherein said multivibrator circuit means are connected to said clock pulse generator means and provide asymmetrical rectangular pulse signals, and said low pass filter means transmit only the attenuated fundamental wave of said asymmetrical pulse signals, said low pass filter means blocking the transmission of higher harmonic signal components in said asymmetrical pulse signals; and said band pass filter means are connected to said low pass filter means for providing a predetermined harmonic region and a predetermined timbre.

Description:
BACKGROUND OF THE INVENTION

The electronic apparatus, in accordance with the present invention, applies tone generators in the form of preferably astable multivibrators to synthesize animal calls in the form of luring calls, warning calls or scare-off calls. The repetition of the calls is controlled through pulses derived from a clock pulse generator. As a result of the application of pulse control multivibrators, it is possible to produce sound spectrums of varying frequency, with simple circuit elements. Through such design, in accordance with the present invention, it is possible to avoid the complex audio filters which are used in the conventional art and in the commonly known apparatuses for sound production.

SUMMARY OF THE INVENTION

An arrangement for producing simulated animal sounds in the form of warning calls, luring calls or scare-off calls. A clock pulse generator produces clock pulses which may be either integrated or differentiated for a portion of the pulse. These pulses are then applied to multivibrators of the astable type and transmitted to loud speakers through the use of power amplifiers. By partially integrating and/or differentiating the pulses, any desirable combination of audio signals may be produced.

The novel features which are considered as characteristic for the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1a to 1d shows the integration and/or differentiation of a pulse, and the resulting frequency function which may be derived from such processing of the pulse, in accordance with the present invention;

FIG. 2 shows a functional block schematic diagram for producing a simple warning cry as may be emitted by a buzzard;

FIG. 3 is a functional block diagram and shows the electronic arrangement for simulating the complicated cry of a wild bird of prey, in which the cry has hoarse character;

FIG. 4 shows a further embodiment for synthesizing animal sounds through the use of a sawtooth generator;

FIG. 5 is a block diagram of a further embodiment for simulating luring calls and scare-off calls; and

FIG. 6 is a block diagram and shows a variation from the embodiment of FIG. 5, in accordance with the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring to the drawing and in particular to FIG. 1a, the rectangular control pulse 1 produces in a multivibrator a constant tone frequency corresponding to the curve 2. In FIG. 1b the curve 3 shows a control pulse which is partially integrated. This pulse produces in the multivibrator a tone signal that decreases in frequency as shown by the curve 4 in FIG. 1b. FIG. 1c shows a control pulse 5 which is partially differentiated. This pulse produces the frequency function corresponding to curve 6 within the sound spectrum. The pulse 7 shown in FIG. 1d, is partially differentiated in the first interval 7'. This pulse 7 is also partially integrated in the interval 7". The tone or audiofrequency resulting from the pulse 7 is shown by curve 8. It is seen from this representation of the curves, that an audiofrequency function of any desired shape may be derived from these pulses.

In accordance with the present invention, a clock pulse generator transmits to the multivibrators pulses which are partially differentiated and/or partially integrated. The pulses thus transmitted are of the desired duration and have the desired interval between pulses. In this manner a sound function is realized which corresponds to a rising or falling animal cry, as described in the relation to FIGS. 1a to 1d. With the arrangement, in accordance with the present invention, from the close sounds spectrums of transmitter, which are specifically designated as animal sounds. As a result, the noise effects applied to humans is maintained at a minimum and not bothersome. In accordance with the present invention, furthermore, it is possible to program different shying and warning signals, through the concept of the electronic circuitry used. In this manner, the animals do not become accustomed to one and the same sound.

In the schematic block diagram of FIG. 2, a signal function is shown for producing a simple warning cry which may be emitted by an animal. A clock pulse generator 9 transmits to a multivibrator 10 pulses 11 which are partially integrated. At the output of the multivibrator 10 appears a modulated pulse 12 which is transmitted to one or more loud speakers 14, by way of a low frequency amplifier 13.

In order to simulate the call of an animal as, for example, a buzzard, it is necessary to apply a tone frequency between 1 to 3 kHz. for the warning cry. A frequency of 1.5 kHz. is preferred. The pulse timing factor should be within the range of 1/4 to 1/2, with 1/2 being the preferred value. The pulse timing factor is the ratio of the duration of the pulse to the total period of the pulse train. The multivibrator 10 is provided with a variable integration network. This integration network is connected between ground and the emitter electrodes of the transistors within the multivibrator (not shown). As a result of this adjustable type of network 15, the required audio function may be corrected with ease.

FIG. 3 shows a block schematic diagram for producing a signal function which simulates electronically a complicated cry of a wild bird of prey. Such a cry with a hoarse character may, for example, be associated with the cry of a falcon. In this case a number of periodic pulses 16 are partially integrated after being emitted from the clock pulse generator 17. These pulses are then applied to a combination of three multivibrators 18, 19 and 20. In this arrangement the main portion of the required audio spectrum is realized through a 100 percent amplitude modulation of the second multivibrator 19. This is accomplished in conjunction with the first multivibrator 18. The pulse timing factor as defined above, has here a value of 1/8 to 1/2. The frequency lies within the range of 500 Hz. to 2 kHz. The preferred value of the pulse timing factor is 1/4.5, and for the frequency as 1.11 kHz. For the second multivibrator 19 a pulse timing factor of 1/6 to 1/2 is applicable. At the same time, a frequency within the range of 1.0 to 4.0 kHz. is applicable to the multivibrator 19. The preferred value for the pulse timing factor is 1/5, and for the frequency the preferred value is 2.5 kHz.

The hoarse characteristic of the sound is produced by a third multivibrator 20 which is connected in parallel with the multivibrators 18 and 19. The output if the multivibrator 20 is applied to the second multivibrator 19 for the purpose of frequency modulating the latter. For the multivibrator 20 the following values are applicable. The pulse timing factor is within the range of 1/5 to 1/2, and the frequency is within the range of 100 to 500 Hz. The pulse timing factor is preferably 1/2 and the frequency is preferably 200 Hz. The resulting mixed frequency is amplified by the stage 21 and transmitted to the loud speaker arrangement 22. The integrating networks 23 and 24 are provided, in accordance with the present invention, to assure the proper audio function of the signal.

FIG. 4 shows an additional embodiment for producing synthetically animal sounds. The pulses 25 from a clock pulse generator 26 are applied to a sawtooth generator 27. The sawtooth function of the generator 27 switches in a wobbly manner the multivibrator 28. The middle frequency of the multivibrator 28 is, for example, in the ultrasonic region. The resulting ultrasonic frequency which is rapidly variable, is applied in the conventional manner to a loud speaker 30. An amplifier 29 serves to amplify the signal in the usual manner, while the loud speaker 30 is made of the proper physical and structural characteristics and dimensions. In accordance with the embodiment of FIG. 4, it is possible to realize a circuit through which the ultrasonic frequency may be made rapidly variable with particular effectiveness.

FIG. 5 shows in block form an embodiment for synthetically producing audio sounds in the form of luring signals and scare-off signals. In this embodiment the clock pulse generator 31 operates a multivibrator 32. The square wave signal having a frequency within the range of 300 to 600 Hz. is applied to a low-pass filter 33 for filtering out the fundamental wave of the signal. The fundamental wave is then applied to a rectifier 34 which is prebiased. The fundamental wave experiences, in this case, an attenuation which corresponds to the sound spectrum resulting from tuning bands or tuning forks. The RC band pass circuits 35 provides selectively the desired harmonic determining timbre regions. The amplifier 36 furnishes the power required for the loud speaker 37. An audio spectrum function may also here be formed through adjustable integration networks which integrate partially the control pulses.

FIG. 6 shows a variation from the embodiment of FIG. 5. A clock pulse generator 38 controls an asymmetrical multivibrator 39. A subsequent low-pass filter 40 blocks the higher harmonics so that only the attenuated fundamental wave is transmitted. Harmonic filters 41 function to produce, moreover, the desired audio region which is then amplified by the stage 42. The amplifier signal is applied to the loud speaker 43 and emitted or radiated from there in the form of an audile sound.

In may be seen from the preceding considerations that, in accordance with the present invention, the apparatus may be constructed with the simple means. The apparatus is, furthermore, extremely reliable in operation even at extreme temperatures. Through the use of transistors, the current requirements of the circuitry is relatively small. As a result, a built-in battery will allow the use of the electronic arrangement over a substantially long period of time, of the order of several weeks, without resorting to a utility outlet.

It will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of constructions differing from the types described above.

While the invention has been illustrated and described as embodied in an electronic arrangement for simulating animal sounds, it is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can by applying current knowledge readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention and, therefore, such adaptations should and are intended to be comprehended within the meaning and range of equivalence of the following claims.

What is claimed as new and desired to be protected by Letters Patent is set forth in the appended




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