Particle handling method by acoustic radiation force and apparatus therefore

• US 5,902,489 A
• Filed: 11/08/1996
• Issued: 05/11/1999
• Est. Priority Date: 11/08/1995
• Status: Expired due to Fees

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Yasuda, Kenji, Shimizu, Norio, Tamura, Mitsuru, Umemura, Shin-ichiro, Takeda, Kazuo
• Primary Examiner(s): Reifsnyder, David A.
• Application Number:
  US08/745,656
• Time in Patent Office: 914 Days
• Field of Search: 209/155, 366/127, 204/660, 204/661, 204/664, 96/115, 96/389, 96/155, 210/748, 210/702, 210/774, 210/94, 210/138, 210/175, 210/188, 210/222, 210/243, 210/294, 210/319, 210/513
• US Class Current: 73/863.21
• CPC Class Codes: B01D 21/283 Settling tanks provided with vibrators
• CPC Class Codes: B01D 21/34 Controlling the feed distribution; Controlling the liquid level ; Control of process parameters
• CPC Class Codes: B01D 43/00 Separating particles from liquids, or liquids from solids, otherwise than by sedimentation or filtration flotation processes B03D1/00; drying solid materials or objects F26B
• CPC Class Codes: B01J 19/10 employing sonic or ultrasonic vibrations

Abstract

A chamber for exerting an ultrasound beam on a sample solution containing particles to be concentrated, separated or arranged is provided with a view toward arbitrarily controlling the shape of a spatial distribution of potential energy created by the ultrasound beam and concentrating, separating or periodically arranging the particles. In contrast to the chamber, irradiation ultrasound sources for generating ultrasound beams are provided to create an ultrasonic intensity distribution for producing a position potential energy distribution used to exert a force forwarded in a predetermined direction or a force staying at a predetermined region to each particle. Thus, a specific spatial distribution of potential energy can be realized by ultrasound beams each having a specific intensity, a specific frequency and a specific phase or an ultrasound beam formed by superimposing these on one another. Further, at least one suction hole for recovering separated solvents or particles is defined in a wall surface of the tube, which is orthogonal to the flow of the sample solution.

Claims

1. A particle method by an acoustic radiation force, comprising the steps of:

generating an ultrasound beam by applying a plurality of superimposed alternating electric voltages having sinusoidal shapes different from one another to a piezoelectric transducer;

applying the generated ultrasound beam to a fluid containing particles in a chamber to be concentrated, filtered or arranged so as to apply a force to the particles; and

varying the force applied to the particles from a force forwarded in a predetermined direction to a force staying at a predetermined region.

2. An apparatus for handling particles by an acoustic radiation force, comprising:

a chamber for accommodating therein a fluid containing the particles to be concentrated, filtrated or arranged;

an ultrasound source disposed so as to make direct or indirect contact with the fluid; and

a control device for controlling said ultrasound source to generate an ultrasound beam by applying a plurality of superimposed alternating electric voltages having sinusoidal shapes differing from one another to said ultrasound source so that the generated ultrasound beam exerts a force forwarded in a predetermined direction or a force staying at a predetermined region on the particles within a sound field of the fluid.

3. An apparatus as claimed in claim 2, further comprising an amplifier having a function of amplifying by ω

'"'"'/ω

times, the amplitude of a voltage vibration of an input angular frequency ω

'"'"' with respect to the amplitude of a voltage vibration of a reference angular frequency ω

.

4. An apparatus as claimed in claim 2, further comprising means for controlling the temperature of the fluid in the chamber for holding the fluid therein.

5. An apparatus for handling particles by an acoustic radiation force, comprising:

a chamber for accommodating therein a fluid containing the particles to be concentrated filtrated or arranged;

a plurality of ultrasound sources each disposed so as to make direct or indirect contact with the fluid; and

a control device for controlling said ultrasound sources independently of each other to generate respective ultrasound beams each having a specific frequency, a specific intensity and a specific phase difference;

whereby the ultrasound beams from said ultrasound sources exert a force forwarded in a predetermined direction or a force staying at a predetermined region on the particles within a sound field of the fluid;

wherein the ultrasound beams generated from said plurality of ultrasound sources produce a standing wave; and

means for controlling the temperature of the fluid in the chamber for holding the fluid therein.

6. An apparatus for handling particles by an acoustic radiation force, comprising:

a chamber for accommodating therein a fluid containing the particles to be concentrated, filtrated or arranged;

an ultrasound source disposed so as to make direct or indirect contact with the fluid;

a control device for controlling said ultrasound source to generate an ultrasound beam by applying a plurality of superimposed alternating electric voltage having sinusoidal shapes differing from one another to said ultrasound source; and

means for exerting at least one of an electric field, a magnetic field and an other external force which is other than the acoustic radiation force on a sample in the apparatus;

whereby the ultrasound beams from said ultrasound beam exerts a force forwarded in a predetermined direction or a force staying at a predetermined region on the particles within a sound field of the fluid.

7. An apparatus as claimed in claim 6, wherein means for observing the state of the particles in the fluid is provided at a position where the particles in the fluid are concentrated or on a side downstream from the position.

8. An apparatus as claimed in claim 6, wherein said control device controls intensities, phases and frequencies produced from said ultrasound sources, or the degree of superimposition of respective intensities, phases and frequencies on one another, or other external force other than the ultrasound beams, based on a distribution of the particles in the fluid, which has been obtained by said observing means.

9. An apparatus for handling particles by an acoustic radiation force, comprising:

chamber for accommodating therein a fluid containing the particles to be concentrated filtrated or arranged;

a plurality of ultrasound sources each disposed so as to make direct or indirect contact with the fluid;

a control device for controlling said ultrasound sources to generate an ultrasound beam obtained by superimposing ultrasound beams each having a specific frequency, a specific intensity and a specific phase difference from said ultrasound sources on one another; and

means for exerting at least one of an electric field, a magnetic field and an other external force which is other than the acoustic radiation force on a sample in the apparatus;

whereby the ultrasound beams from said ultrasound sources exert a force forwarded in a predetermined direction or a force staying at a predetermined region on the particles within a sound field of the fluid; and

wherein a tube is provided at a position for sucking concentrated particles in the fluid on a downstream side of said tube together with the fluid, or a tube is provided for sucking the fluid on a downstream side of said tube at a position other than a position where the particles have been concentrated.

10. An apparatus as claimed in claim 9, further comprising means for displacing the position of said tube.

11. An apparatus as claimed in claim 9, wherein means for observing the state of the particles in the fluid is provided at the position where the particles in the fluid are concentrated or on the side downstream from the position.

12. An apparatus as claimed in claim 9, wherein said control device controls intensities, phases and frequencies produced from said ultrasound sources, or the degree of superimposition of these respective ones on one another, or other external force other than the ultrasound beams, based on a distribution of the particles in the fluid, which has been obtained by said observing means.

13. A particle handling apparatus comprising:

a channel for passing a solution containing solvent components and particle components therethrough;

means for applying an ultrasound beam in a direction substantially orthogonal to a flow of the solution in the channel to thereby generate a node of acoustic pressure of a standing wave at a predetermined position in the channel; and

a suction hole defined in a wall surface of said channel substantially orthogonal to the flow of the solution in the channel and having a diameter smaller than a wavelength of the ultrasound beam.

14. A particle handling apparatus as claimed in claim 13, wherein said means controls the frequency, phase and intensity of an ultrasound beam produced from each of ultrasound sources, which acts on at least opposed wall surfaces.

15. An apparatus as claimed in claim 13, wherein said means for applying the ultrasound beam includes means for superimposing ultrasound beams each having specific frequency, a specific intensity and a specific phase difference from ultrasound sources on one another, so that the ultrasound beams from said ultrasound sources exert a force forwarded in a predetermined direction or a force staying at a predetermined region on the particles within a sound field of the fluid.

16. An apparatus as claimed in claim 15, wherein said means for applying the ultrasound beam including means for varying at least one of the specific frequencies, intensities and phase differences of the ultrasound beams from said ultrasound source independently of each other according to time so that the predetermined region is changed according to time.

17. A particle handling apparatus comprising:

a channel for passing a solution containing solvent components and particle components therethrough;

means for applying an ultrasound beam in a direction substantially orthogonal to a flow of the solution in the channel to thereby generate a node of acoustic pressure of a standing wave at a predetermined position in the channel; and

suction holes respectively defined in wall surfaces of said channel, substantially orthogonal to the flow of the solution in the channel and opposed to each other and having diameters smaller than wavelength of the ultrasound beam;

said wall surfaces having said holes are conductive or are of a magnetic material and are capable of applying a force produced by an electric field or magnetic field other than a force produced by the ultrasound beam to said each particle.

18. A particle handling apparatus as claimed in claim 17, wherein said means controls the frequency, phase and intensity of an ultrasound beam produced from each of ultrasound sources, which acts on at least the opposed wall surfaces.

19. A particle handling apparatus comprising:

a channel for passing a solution containing solvent components and particle components therethrough;

means for applying an ultrasound beam in a direction substantially orthogonal to a flow of the solution in the channel to thereby generate a node of acoustic pressure of a standing wave at a predetermined position in the channel;

a first solution supply port defined in a wall surface of said channel, substantially orthogonal to the flow of the solution in the channel and having a diameter smaller than the wavelength of the ultrasound beam, said port being used to supply a reaction solution which acts on the particles;

a second solution supply port defined in the wall surface of said channel and having a diameter smaller than the wavelength of the ultrasound beam, said port being used to supply a dilute solution for diluting a reaction solution to the side downstream from said first solution supply port; and

a suction hole provided at a position opposed to said second solution supply port or defined in the wall surface of said channel on the side downstream from said second solution supply port, said suction hole having a diameter smaller than a wavelength of the ultrasound beam.

20. A particle handling apparatus as claimed in claim 19, wherein said means controls the frequency, phase and intensity of an ultrasound beam produced from each of ultrasound sources, which acts on at least opposed wall surfaces.

21. A particle handling apparatus as claimed in claim 19, further comprising a stirrer provided on the side downstream from said first solution supply port and used to promote a contact between the reaction solution and the particles.

22. An apparatus as claimed in claim 19, wherein said means for applying the ultrasound beam including means for superimposing ultrasound beams each having a specific frequency, a specific intensity and a specific phase difference from ultrasound sources on one another, so that the ultrasound beams from said ultrasound sources exert a force forwarded in a predetermined direction or a force staying at a predetermined region on the particles within a sound field of the fluid.

23. An apparatus as claimed in claim 22, wherein said means for applying the ultrasound beam includes means for varying at least one of the specific frequencies, intensities and phase differences of the ultrasound beams from said ultrasound sources independently of each other according to time, so that the predetermined region is changed according to time.

24. A particle handling apparatus comprising:

a chamber for holding therein a sample solution containing dissolved gas components, solvent components and particle components;

degassing means supplied with the sample solution, for removing dissolved gas components in the solution;

a channel for passing the degassed sample solution therethrough;

means for applying an ultrasound beam in a direction substantially orthogonal to a flow of the solution in the channel to thereby generate a node of acoustic pressure of a standing wave at a predetermined position in the channel;

at least one suction hole defined in a channel wall surface substantially orthogonal to the flow of the solution in the channel and having a diameter smaller than a wavelength of the ultrasound beam;

a changeover valve for changing the flow of the solvent components or the particle components sucked through said suction hole;

a changeover valve for changing the flow of the solvent components or the particle components unsucked through said suction hole;

pipes for discharging the solvent components or the particle components through said their corresponding valves;

pipes for returning the solvent components or particle components to the tube through said their corresponding valves; and

a control device for controlling said respective elements.

25. A particle handling apparatus as claimed in claim 24, wherein a generating means controls the frequency, phase and intensity of an ultrasound beam produced from each of ultrasound sources, which acts on at least opposed wall surfaces.

26. An apparatus as claimed in claim 24, wherein said means for applying the ultrasound beam includes means for superimposing ultrasound beams each having a specific frequency, a specific intensity and a specific phase difference from ultrasound sources on one another, so that the ultrasound beams from said ultrasound sources exert a force forwarded in a predetermined direction or a force staying at a predetermined region on the particles within a sound field of the fluid.

27. An apparatus as claimed in claim 26, wherein said means for applying the ultrasound beam includes means for varying at least one of the specific frequencies, intensities and phase differences of the ultrasound beams from said ultrasound sources independently of each other according to time so that the predetermined region is changed according to time.

28. An apparatus for handling particles by an acoustic radiation force, comprising:

a chamber for accommodating therein a fluid containing the particles to be separated;

a plurality of ultrasound sources disposed so as to make direct or indirect contact with the fluid;

a control device for controlling said ultrasound sources to generate an ultrasound beam; and

means for exerting an electric field, the electric field being generated by electrode plates attached to faces of said ultrasound sources in said chamber;

wherein an acoustic radiation force and an electrostatic force are both irradiated simultaneously from a same inner face of said chamber in a same direction and separate different kinds of particles in the fluid; and

wherein a tube is provided at a position for sucking particles in the fluid on a downstream side of said tube together with the fluid, or a tube is provided for sucking the fluid on a downstream side of said tube at a position other than a position where the particles have been concentrated.