Ultrasonic cleaner and degreaser

July 28, 1959 m. a. lazarus 2,896,648

ULTRASONIC CLEANER AND DEGREASER

Filed Aug. 25, 1958

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r £JV 1 UK.

MaxZLazafu.s

ATTORNEY

United States Patent Office

2,896,64$

Patented July 28, 1959 ¹

2,896,648

ULTRASONIC CLEANER AND DEGREASER Max A. Lazaros, South Orange, NJ.

Application August 25,1958, Serial No. 756,898 4 Claims. (CI. 134—147) (My invention relates generally to ultrasonic cleaners and degreasers and specifically to watch part cleaners and degreasers.

It is an object of my invention to propagate and direct * ultrasonic vibrations into intimate contact with watch parts continuously in motion whereby unwanted encrustations and other materials are discharged or detached from their surface.

It is another object of my invention to provide an ultrasonic vibration means which has a central aperture to surround a shaft which is the axle for rotation of a basket to contain work pieces.

These objects and advantages as well as other objects and advantages may be achieved by the device shown by way of illustration in the drawings in which—

Figure 1 is a side elevational view of my ultrasonic cleaner and degreaser; and

Figure 2 is a vertical sectional view of the transducer.

Ultrasonic vibrations in liquids have been used for cleaning and degreasing, but my cleaning and degreasing device maintains objects to be degreased and cleaned within a narrow orbit which traverses a path at all times equidistant from the transducer and close thereto, so that the liquid column is short, the transducer hollowcircular, and the objects revolved on a shaft introduced through the transducer.

My ultrasonic cleaning and degreasing device utilizes a conventional source of high frequency alternating cur,4 rent or electrical energy such as is generated by a radio frequency generator and a transducer element such as a ’ piezoelectric crystal 11 in circuit with the source of energy m order to oscillate the crystal 11. A metal plate » 12 is secured to the bottom of the crystal, by a suitable cement. The current is conducted to the bottom metal plate 12 by a wire 13 attached thereto and another wire 14 is attached to the top of the crystal by cement. The crystal 11 is circular with an axial passage 15. The crystal 11 is positioned in a housing 10 which has a convex bottom 16. A side wall 17 is attached to the bottom and a top 18 is attached to the side wall at the top thereof. Both the top 18 and the bottom 16 are provided with axial openings. In these openings, attached to the top 18 and the bottom 16 is a tubular core 22 defining a shaft passage. The top 18 has an aperture for the introduction of the electric leads 13,14. An annular suspension bracket 19 is also attached to the top 18, and to the bottom of a motor housing 9.

The apphcation of the current to the crystal 11 will cause the generation in ultrasonic vibration which is imparted to the bottom 16. Gases, such as air wiU cause a rapid attenuation of an ultrasonic signal. The contacting of the bottom 16 with a liquid, such as a cleansing agent will effect a violent agitation of the liquid molecules, which will cause them to impinge upon any object in the liquid which is to be cleaned or degreased. The liquid column extending from the transducer to the object should be relatively short and should not be substantially obstructed or interrupted. To place the trans2 ducer on one side of an object, or a collection of objects, is not altogether effective since some objects and areas escape the effects of the ultrasonic vibrations. This suggests that the objects be agitated by moving them in 5 closer relation to the transducer. This has not been found as effective as might be anticipated.

If, however, the transducer is so disposed as to be coaxial with the center of rotation of the object or objects, a vastly enhanced cleaning and degreasing effect is 10 achieved uniformly over the entire surface of the object or objects. To achieve this, the transducer is made circular and a shaft 20, for rotating a foraminous basket 21 is introduced through the core 22. The basket 21 is detachably secured to a top or closure 23 which is secured 15 to the bottom of the shaft 20. The shaft 20 is also the shaft of a motor 24. The motor 24 is slidably mounted on a vertical support 25 so that it may be raised and lowered, and a set-screw 26 will lock it at any chosen level. The support 25 is hollow and conducts the cur20 rent supply wires for the motor to the base 28 where a toggle switch 27 turns the motor on or off and, as well, - energizes the source of power to the transducer. The support 25 is mounted on the base 28. A detergent cup 29 is also mounted on the base.

When a cleansing or degreasing operation is desired, the objects, such as watch parts are deposited in the basket 21, which is secured to the top or closure 23. The set-screw 26 is loosened and the motor 24 is moved until the shaft 20 is over the cup 29. The motor is then 30 lowered until the basket 21 has entered the detergent 31 and the bottom 16 is immersed in detergent 31. The switch 27 energizes the motor circuit and the source of supply for the transducer. The basket 21 rotates, its speed being adjusted by a rheostat 30. The bottom 16 35 being disposed in juxtaposition with the objects in the basket 21, with a relatively short-liquid column, the agitation of the molecules of the detergent 31 is intense and the objects in the basket are at all times during their circuit of rotation equidistant from the transducer, a rela40 tionship achieved only by a “doughnut” transducer concentric with the axis of rotation of the basket.

The solvent action of the detergent 31 removes grease from the objects, the agitation of the objects through rotation removes lightly adherent encrustations, and the vi45 bration of the liquid molecules (unattenuated and uniformly applied to all objects in the basket), detaches the strongly adherent encrustations leaving the objects clean. A rinse cup may follow the detergent cup. An antifoaming agent in both cups will eliminate undesirable go foam.

A highly effective cleansing and degreasing action results from the combination of controlled and directed ultrasonic vibrations exerted on objects at all times closely equidistant from the transducer although they are in mogg tion.

The foregoing description is merely intended to illustrate an embodiment of the invention. The component parts have been shown and described. They each may have substitutes which may perform a substantially simi60 ’^ar function; such substitutes may be known as proper substitutes for the said components and may have actually been known or invented before the present invention; these substitutes are contemplated as being within the scope of the appended claims, although they are not specifically catalogued herein.