US 3138138 A
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Description (OCR text may contain errors)
June 23, 1964 QUlTTNER 3,138,138
PEST CONTROL Filed Nov. 8, 1961 15- M I 5 P (NVENTOR.
United States Patent ration of Ohio Filed Nov. 8, 1961, Ser. No. 151,595 2 Claims. (Cl. 116-137) The present invention relates to apparatus and methods for the inhibition of pests.
It is well known that many pestiferous rodents, insects, birds, and'the like, find ultrasonic sound waves unpleasant, and in some cases incapacitating, discouraging, or deadly. Because of the magnitude of the problem much work has been done on electronic means for the generation and control of such energy.
Published technical reports as well as patents teach that many pests react strongly to sound in the frequency range just above that of human hearing, namely 15 or 18 kc. to 25 kc., so that such devices are often usable without undue annoyance to humans.
Nevertheless the commercial success of such devices has been nearly zero, because in practice they have proved ineffectual. It is demonstrable by experiment that not only are relatively high intensities (over 100 db sound pressure) required, but also that the pests sometimes rather easily accommodate themselves to the annoyance unless some means is employed to render the radiation discontinuous, and preferably varied in other ways as well.
Within economically practical unit costs electronic means are limited by the inability to provide sufficient radiated power, mostly because of transducer difliculties. Electro-mechanical transducers require the vibration of a surface, e.g., paper cone or metal diaphragm, to transduce electrical oscillations to air pressure waves. The coupling of such vibrations efliciently to air at high power levels presents formidable technical difliculties.
A further weakness in existing ultrasonic sound pest deterrents involves the highly directional propagation characteristics of ultrasonic energy in air. Thus, a relatively expensive electromechanical system may produce adquate sound pressure in a narrow beam, but to properly illuminate a practical area, numerous transducers have been required, correspondingly greatly increasing the cost of the arrangement.
Besides high cost in any event, a further difliculty with electronic systems involves the necessity for safe operation in explosion hazardous areas, such as granaries. The provision of truly explosion proof electronic equipment requires either heroically heavy encasing or use of very high current low voltage devices with corresponding disadvantages in weight, size, efliciency and cost.
It is an object of the present invention to provide inexpensive means which avoid the difliculties outlined above.
Further objects and advantages of the invention will become apparent and the invention may be better understood from consideration of the following description taken in connection with the accompanying drawing, in which:
FIG. 1 is a perspective view of apparatus according to the invention; and
FIG. 2 is an enlarged longitudinal vertical section through the apparatus the outside of which is shown in FIG. 1.
According to one aspect of the invention, pest deterrent means (to cause pests either to become annoyed to death or at least to vacate the adjacent premises) employs compressed air or other fluid fed to a high frequency whistle as a source of ultrasonic wave energy (e.g., in air) in combination with a pneumatic motor op- 3,138,138 Patented June 23, 1964 erated device for intermittently turning the flow of compressed air on and off automatically. A helpful refinement is provided by mechanical means for varying the direction of propagation automatically but out of sequence with the turning on-and-oti (or average level amplitude alteration).
Referring to FIGS. 1 and 2, a source of compressed fluid (preferably air) is led to the device through a hose 10. The main flow is to a motor operated valve 12 which controls the flow to a whistle 13. Auxiliary fluid flows to a manually operated valve 14 which controls flow to a small pressure fluid operated motor 15, operatively connected to continuously change the setting of the valve 12. Another auxiliary fluid connection is to a manually operated valve 16 which controls the flow to a pressure fluid motor 17 Valve 12 can be a standard item of manufacture such as a rotary on-otf valve. Motor 15 driving such a valve can be of conventional rotating vane type. Motor 17 can be of the same type. For the manually operated valves 14 and 16, commercially available needle valves are suitable.
The whistle 13 may be of known type. See, for example, U.S. Patent 2,245,484, issued June 10, 1941, having the refinement of a manually adjustable plunger which allows an operator to test the whistle with one setting, to which the human ear responds, and thereafter give it another setting so that the output is audible only to certain animals while not audible to humans or large dull creatures such as those of the bovine species.
In the illustrated embodiment, the whistle 13 is provided with a coupling horn 18 projecting through a containing box 19. A suitable sound reflector 20 is rotatably supported on an open center rotatable bearing plate 21 provided with driving means such as gear teeth engaging matching teeth of a motor 17 driven pinion 23. The gears and bearing may be protected by a cover 24. The reflector may have one or more support posts 25.
Motor 15 and valve 12 can turn whistle 13 on and off automatically, at a frequency depending on adjustment of manual valve 14, although other means may be used to provide the periodic change in average output. The rate of rotation (or oscillation, if that mode of operation is selected) of reflector 20 by motor 17 is controlled by valve 16. Because there is no mechanical coupling between motor shafts, rotation rate of the reflector will only with difliculty and then impermanently be integrally related to whistle on-off periodicity. Therefore, in general, each time the whistle is energized its sound output beam will be directed somewhat differently.
Although this device may include a small electrically driven air compressor, in most application areas it is advantageous to have (or there may already be) a remotely located compressor. A single compressor supplying several units may be more economical than several smaller compressors. A remote compressor also may be located advantageously outside an explosionhazardous area. The compressorless unit described is thus small, light, and easy to position.
It is well known that pests, particularly highly organized pests such as rodents, easily learn to accommodate to minor and some major discomforts. Such accommodation being undesirable for the purposes of practicing my invention, not only is the sound made discontinuous, but with a preferred embodiment the apparent source location is continually changed, due to the reflection of the sound from the moving reflector and from reflection by Walls, etc., in the application area. Reflector rotation, moreover, permits relatively very high intensities, -120 db of sound pressure, for example, to be efliciently produced in a narrow beam, and yet to illuminate a relatively large area. Nevertheless, for certain applications it may be advantageous for the reflector to oscillate rather than continuously rotate, or even for it to be stopped or omitted. If desired, the reflector could be made to rotate about a vertical axis and simultaneously oscillate up and down, a whistle source or horn could be rotated or oscillated instead of just a reflector, and any motion could be made intermittent rather than continuous (see US. Patents 1,208,887 and 1,459,220).
Clearly the spirit and basic principles of my invention can be utilized in other ways than with the apparatus selected for illustration, but the claims hereinafter attached are intended to cover such cases.
1. Apparatus useful for the control of pests, said apparatus comprising:
an ultrasonic wave generating means,
pressure conduit means connected to energize said wave generating means,
first and second motor means,
a valve means interposed in said conduit means and .4 connected to be driven by the first motor means whereby to automatically periodically alter wave energy output from said generating means,
and a separate automatically operated means connected to be driven by the second motor and mechanically connected to automatically alter direction of wave energy output from said generating means.
2. The combination of claim 1 further characterized by the valve means and the separate automatically operated means being independently manually adjustable whereby to assure that energy output alterations and direction alterations will occur asynchronously.
References Cited in the file of this patent UNITED STATES PATENTS 617,856 'Foster Jan. 17, 1899 1,134,554 Pernot Apr. 6, 1915 1,459,220 Krause June 19, 1923 1,973,673 Rice Sept. 11, 1934 2,971,491 Yeogley Feb. 14, 1961