Method and Apparatus for Washing Fabrics Using Focused Ultrasound

• US 20100146713A1
• Filed: 11/19/2009
• Published: 06/17/2010
• Est. Priority Date: 11/21/2008
• Status: Abandoned Application

• Current Assignee: InSightec Ltd.
• Original Assignee: InSightec Ltd.
• Inventors: Vitek, Shuki, Vortman, Kobi, Medan, Yoav
• Application Number:
  US12/621,710
• Publication Number:
  US 20100146713A1
• Time in Patent Office: Days
• US Class Current: 8/137
• CPC Class Codes: D06F 19/00 Washing machines using vibrations for washing purposes

Abstract

Systems and methods in accordance with the invention cause substantially the entire area of a fabric article to be laundered is efficiently and completely exposed to focused ultrasound. In this way, the benefits of cavitation are applied to the article as a whole rather than on a “spot” basis.

Claims

1. Apparatus for laundering fabric articles, the apparatus comprising:

a cavitation chamber for receiving the fabric articles to be laundered;

a source of ultrasound energy focusing to one or more foci within the cavitation chamber; and

a handling system for ensuring that substantially the entireties of the fabric articles pass at least once through a cavitation region during a cleaning cycle.

2. The apparatus of claim 1 wherein the handling system includes a feeding mechanism to draw the articles into the chamber.

3. The apparatus of claim 2 wherein the feeding mechanism comprises an Archimedes screw.

4. The apparatus of claim 1 further comprising means for enforcing a standing-wave condition in the cavitation chamber.

5. The apparatus of claim 1 further comprising means for introducing micro-bubbles into the cavitation chamber, whereby the fabric articles are exposed to streaming and inertial cavitation.

6. The apparatus of claim 1 further comprising a sensing module to monitor the extent of cleaning and a controller, responsive to the sensing module, for causing water in the cavitation chamber to be filtered or replaced with a new or recycled volume of water.

7. The apparatus of claim 1 further comprising a sensing module to monitor cavitation and a controller, responsive to the sensing module, for responsively altering at least one of acoustic power, a temporal transmission regime or frequency of the ultrasound energy.

8. The apparatus of claim 1 wherein the cavitation chamber is cylindrical with a first portion containing an acoustic transducer with a line focus extending axially along the center of the chamber and a second portion opposed to the first portion forming a reflector.

9. The apparatus of claim 1 where the ultrasound energy is focused to multiple foci distributed within the cavitation chamber.

10. The apparatus of claim 1 further comprising a separate cleaning chamber, the handling system transferring fabric articles from the cleaning chamber to the cavitation chamber.

11. The apparatus of claim 1 wherein the cavitation chamber is in the form of a drum having, disposed along an inner wall thereof, a series of acoustic-wave emitting plates having axial foci each at different focal depths.

12. The apparatus of claim 11 wherein the emitting plates have the same focal depth and further comprising, opposed to each emitting plate, a reflector with a different focal depth.

14. The apparatus of claim 12 further comprising a water-handling system for introducing water into and withdrawing water from the rotatable chamber during a cleaning cycle.

18. The apparatus of claim 11 wherein the ultrasound sources have foci at different focal depths.

13. Apparatus for laundering fabric articles, the apparatus comprising:

a rotatable chamber for receiving the fabric articles to be laundered, at least a portion of the chamber being substantially transparent to ultrasound energy;

surrounding the rotatable chamber, at least one stationary ultrasound source for directing ultrasound energy to different foci within the chamber; and

a controller for rotating the chamber and selectively activating the at least one ultrasound source during the rotation.

15. The apparatus of claim 13 wherein the controller ensures a minimum water level during activation of the ultrasound sources.

16. The apparatus of claim 13 wherein at least a portion of the rotatable chamber is substantially transparent to ultrasound energy.

17. The apparatus of claim 13 comprising a plurality of circumferentially spaced-apart ultrasound sources, wherein the rotatable chamber has a plurality of circumferentially spaced-apart windows transparent to ultrasound energy and, between the windows, segments of a material that reflects ultrasound energy.

19. The apparatus of claim 15 wherein the ultrasound sources have a consistent focal depth and the reflecting segments each have a different focal depth.

20. Apparatus for laundering fabric articles, the apparatus comprising:

a chamber for receiving the fabric articles to be laundered;

means for directing ultrasound energy into the chamber;

a handling system for drawing fabric articles through the chamber; and

means for introducing micro-bubbles into the chamber, whereby the fabric articles are exposed to streaming and inertial cavitation, the micro-bubbles having sizes optimized to enhance cavitation.

21. A method of laundering fabric articles, the method comprising the steps of:

receiving, in a chamber, the fabric articles to be laundered;

directing ultrasound energy to one or more foci within the chamber; and

handling the fabrics such that substantially the entire areas of the fabric articles pass at least once through a cavitation region during a cleaning cycle.

22. A method of laundering fabric articles, the method comprising the steps of:

receiving, in a chamber, the fabric articles to be laundered so the articles are submerged in a liquid;

directing ultrasound energy into the chamber;

drawing fabric articles through the chamber; and

introducing micro-bubbles into the chamber, whereby the fabric articles are exposed to streaming and inertial cavitation.

23. A method of laundering fabric articles, the method comprising the steps of:

rotating a chamber in which the fabric articles are submerged in a liquid; and

during the rotation, selectively activating a plurality of circumferentially disposed, stationary ultrasound sources around the chamber to direct ultrasound energy to different foci within the chamber.