US2783733A

US2783733A - Apparatus for generating directed high frequency sound waves

Info

Publication number: US2783733A
Application number: US369607A
Authority: US
Inventors: Chertoff Israel
Original assignee: Individual
Current assignee: Individual
Priority date: 1953-07-22
Filing date: 1953-07-22
Publication date: 1957-03-05
Anticipated expiration: 1974-03-05

Description

March 5, 1957 I. CHERTOFF APPARATUS FOR GENERATING DIRECTED HIGH FREQUENCY SOUND WAVES Filed July 22, 1953 mum/Ton. f5 erfof/ United States Patent cc APPARATUS FOR GENERATING DIRECTED HIGH FREQUENCY SOUND WAVES The present invention relates to an apparatus for generating high frequency sound waves.

In U. S. patent application Serial No. 284,091 of April 24, 1952, of which this application is a continuation-inpart, an apparatus for generating directed high frequency sound waves is disclosed, the said apparatus comprising mounted fixedly within the throat of a Venturi tube a hollow cone having a. series of openings and a hollow rotary cone nesting with the said fixed cone and having a series of Venturi openings in register with the openings of the fixed cone. When air or another gaseous medium is blown through the Venturi tube and the rotary cone is turned at high speed, sound waves are created at frequencies above the audible range. The device is very effective in disintegrating and dispersing liquid dropletsinjected into the gaseous stream.

The advantage of the afore-mentioned cone-shaped mechanism for producing high frequency sound waves lies inthe fact that the sound waves are directed toward a focal point. As a result, atomization of liquid droplets dispersed at or near the focal point takes place at far greater efliciency than by means of prior devices producing audio waves at random distribution.

The present disclosure relates to improvements in the afore-described device. One improvement is a substantial increase in the relative speed at which the sets of openings in one cone rotate past the sets of openings in the other cone, resulting in much higher frequencies. The other improvement relates to a further concentration of waves and to the production of a cumulative ultrasonic effect within the desired region of the Venturi tube by means of a reflector especially designed to permit substantially unimpeded flow of the gaseous medium.

It is, therefore, one object of the present invention to provide improved means for generating directed high frequency sound waves and to provide means for reflecting such sound waves to a focal point within a Venturi tube adapted for high speed passage of a gaseous medium.

It is another object of the invention to use the focalizing effect of the device upon high frequency sound waves produced therewith to atomize droplets of liquid injected into a gaseous stream, such as droplets of fuel or fuel and water for the operation of an internal combustion engine.

Other objects of the invention will in part be obvious and in part hereinafter be pointed out.

In the accompanying drawings, showing an illustrative embodiment of the invention:

Fig. 1 is a sectional view along the axis of the device,

Fig. 2 is an enlarged view of one of the relief valves,

Fig. 3 is a cross-sectional view taken on the line 3-3 in Fig. 1, and

Fig. 4 is a cross-sectional view taken on the line 4-4 in Fig. 3.

Referring in more detail to the drawings, the numeral designates a tube having a Venturi-shaped constriction 11. Arranged within the tube as shown are the three spiders 12, and 18 which are formed with central hubs 13, 16 and 19, respectively. Mounted within these hubs are ball bearings, such as the ball bearings 14 and 20.

Extending from the hub 13 and journalled to be retained in position by the said hub is the shaft 23 which has a hollow cone 24 attached to the free end thereof. This cone is provided with a plurality of circularly ar ranged openings such as the opening indicated at 25. The shaft 23 and the cone 24 are held in an accurate, spaced co-axial position with respect to a hollow shaft 26 by means of the ball bearing 21 arranged shortly below the cone and by means of a similar ball bearing arranged within the hub 16. The hollow shaft 26 expands at its upper end into a hollow cone 27 nesting with the aforedescribed cone 24. Being of substantial wall-thickness, the hollow cone 27 is provided with a plurality of circularly arranged, Venturi-shaped openings, such as the opening 28, which are in linear register with the openings cut into the cone 24.

Arranged flush with the hollow cone 24 is a collar 30 provided with a number of valves such as the valve 31. The lids 32 of these valves are fastened to the collar by means of the hinges 33 and, in the absence of excessive gaseous pressure, are held in a closing position by the torsion springs 34.

The free end of the hollow shaft 26 is fixedly attached .to the hub 36 of a gear wheel 37, forming part of a right angle bevel gear system comprising the said gear wheel,

a driven gear wheel 38 having a drive shaft 39 adapted to be coupled to a rotatory power source such as an electric motor, and the gear wheel 40 supplying rotary motion to the shaft 23. As indicated in Fig. 3 at 41, the

cylindrical shape of the tube 10 is box-like enlarged in part to accommodate the gear wheel 38 and the bearing 42 fitted through the wall of the tube.

The gear wheel 37 and the gear wheel 40 are provided with four spokes each. These spokes, such as the spoke 45, are made relatively flat and, as shown in Fig. 4, are set at an angle so that, upon rotatiton of the gear wheels, the spokes will assume the function of blades of a fan or propeller and cause a rapid motion of gaseous medium toward the Venturi section 11 as indicated by the arrows in Fig. 1.

Mounted fixedly inside the Venturi tube 11, preferably within the space between the spiders 15 and 18, is a reflector to cast back propagated ultrasonic waves. Ordi narily, any suitable reflector of conical or parabolic shape would be suitable. However, due to the necessity of moving a gaseous stream toward the high frequency sound producing device, in order to retain the inherent simplicity of design, I have cut the wall of the reflector into a spiral band 50 and have separated the individual loops practically free passage of a gaseous medium therethrough. In the drawing, a reflector of conical shape is shown. Obviously, a parabolic reflector spirally opened in the same manner can be used in place thereof. Moreover, by eliminating the spider 18 or by moving the said spider further down if desired, the reflector can be located closer to the cone 27.

As an illustration of the use of the device, the

inlet pipes

51 and 52 enter into the Venturi tube 11 arranged in such a manner that their

nozzles

53 and 54 are located next to each other within the focal region ofthe high frequency sound. Liquid droplets ejected from the nozzles undergo an instantaneous and efiicient atomization.

It will be understood that, as the shaft 39 is rotated at high speed, the gear wheel 38 turns the gear wheel 37, the shaft 26 and the hollow cone 27 in one direction, while the gear wheel 40, the shaft 23 and the hollow cone 24 is turned in the opposite direction. The said gear arrangement can be set up with toothed wheels or with Patented- Mar. 5, 1957 whcelsmakingfrictional contact with each other. Due to the propelling efiect of the blades 45, a gaseous stream moves at great velocity toward the cones and, in passing through the openings in the rotating cones, produces high frequency sound waves converging at afocal point in front of their piaee of origin. Insofar as these sound waves are capable of travelling backward, par-ticat'larly if the lids 32 are raised, they are again reflected forward by the spiral band 50.

The valves 31 are adapted to open it the back pressure created by the cones restricting the gaseous flow exceeds a predetermined point. The holes cut into the cone 24 and the Venturi openings provided at the cone 27 are preferably" arranged in registering circles, although there does not need to be the same number of openings in the respective circles,

Since it is possible-to reduce the invention to practice by means of embodiments other than the embodiment disclosed without'departing from the spirit of the invention, it-

to be understood that all matter herein set forth is to beinterpreted as illustrative and not in a limiting sense.

I claim:

I. In an apparatus for generating directed high frequency sound waves, the said apparatus comprising a Venturi tube,- means for passing a gaseous stream through the said Venturitube, mounted at the throat of the said Venturi tube aninternal flange carrying a plurality of spring operated valves adjusted to open upon a given pressure increment, fixed transversely within the annular opening of. the said flange a first hollow cone having series of openings and nesting with the said fixed cone a second hollow rotary cone which is thick-walled and has series of Venturi-shaped openings in linear register with the series of openings in the said fixed cone, the improve ment of mounting both of the cones rotatably, providing means for rotating the said cones in opposite directions said second cone is mounted at one end of a hollow shaft and the said first cone is mounted at one end of a solid shaft of lesser diameter in order to pass through the said hollow shaft, right angle bevel gear wheels are attached to the other ends of the said shafts and a third right angle bevel gear wheel adapted to be turned by an appropriate power source is mounted to rotate the said shafts and the said first two gear wheels in opposite directions.

3. The improvement according to claim 2, in which the spokes ofthe gear wheels attached to the said shafts are given the shape and pitch of propeller blades to produce, upon rotation of the said gear wheels, a rapid motion of gaseous medium toward the said cones.

4. The improvement according to claim 2, in which the said Venturi tube is provided with a box-like enlargement at one side to accommodate the said third bevel gear wheel within the said tube.

5. The improvement according to claim 2, in. which the said bevel gear wheels are toothed wheels.

6. The improvement according to claim 1, in which the said spiral reflector is cut from a cone.

References Cited in the file of this patent UNITED STATES PATENTS 1,939,302 Heaney Dec. 12, 1933 2,153,500 Eaves Apr. 4, 1939 2,364,987 Lee Dec. 12, 1944 2,414,494 Vang Ian. 21, 1947 2,436,570 Hancock Feb. 24, 1948 2,454,900 Vang Nov. 30, 1948 2,532,554 Joeck Dec. 5, 1950 2,535,680 Horsley et a1 Dec. 26, 1950