Avoidance of bouncing and splashing in droplet-based fluid transport

Patent metadata

Field	Value
Publication number	US-10118186-B2
Application number	US-201715409229-A
Country	US
Kind code	B2
Filing date	Jan 18, 2017
Priority date	Mar 14, 2005
Publication date	Nov 6, 2018
Grant date	Nov 6, 2018

Abstract

A system for fluid transport is provided where a quantity of fluid is held in a reservoir. A droplet generator is employed to generate droplets from the fluid, for example a nozzle-based system or a nozzleless system such as an acoustic ejection system. A generated droplet has a trajectory whereby it arrives at a target. A circuit is used to modify one or more characteristics of the generated droplet in a way which increases the likelihood that the droplet will not splash or bounce when it arrives at the target. The circuit may in different embodiments control the speed of the droplet or the Weber number of the droplet. The circuit may create an electric field in an area of space where the droplet passes. The circuit may charge the droplet by causing it to contact ions.

First claim

We claim:

1. A system for transporting a fluid to a target, the system comprising:
a reservoir containing a quantity of the fluid;
an acoustic radiation generator configured to eject a droplet from the fluid in the reservoir toward the target at a droplet velocity;
the target configured to receive the ejected droplet;
a first electrode comprising a grid disposed behind the target;
a second electrode; and
a circuit in operable communication with the first electrode and the second electrode and configured to apply a voltage across the first electrode and the second electrode without substantially affecting the droplet velocity.

2. The system of claim 1 , wherein the circuit is further configured to generate an electric field through which the droplet passes.

3. The system of claim 2 , wherein the circuit is further configured to generate the electric field having a magnitude between 1000 and 100,000 V/m at a free surface of the fluid in the reservoir.

4. The system of claim 2 , wherein the circuit is further configured to cause the ejected droplet to be electrically charged.

5. The system of claim 2 , wherein the circuit is configured to hold the voltage at a predetermined voltage for a predetermined period of time.

6. The system of claim 2 , wherein the circuit is further configured to vary the generated electric field with time.

7. The system of claim 2 , wherein the circuit is further configured to generate the electric field that does not cause the ejected droplet to deviate substantially from a path the droplet would travel in absence of the generated electric field.

8. The system of claim 7 , wherein the circuit is further configured to generate the electric field that does not cause the ejected droplet to deviate substantially from the path the droplet would travel in absence of the generated electric field, the path beginning with ejection and ending with impact of the droplet on the target.

9. The system of claim 2 , wherein the circuit comprises an input allowing external logic to control a magnitude of the electric field.

10. The system of claim 2 , wherein the circuit comprises an input allowing external logic to switch a magnitude of the electric field between a predetermined value and zero.

11. The system of claim 2 , wherein the circuit comprises a charging device which charges the target.

12. The system of claim 1 , wherein the acoustic radiation generator is further configured to eject the droplet at the droplet velocity that lies within a range of 1.0 to 2.5 m/s.

13. The system of claim 1 , wherein the acoustic radiation generator is further configured to eject the droplet that travels in a direction which is at an angle of 90 degrees to 180 degrees to the direction of the earth's gravitational field as the droplet arrives at the target.

14. The system of claim 1 , wherein the acoustic radiation generator is nozzleless.

15. The system of claim 1 , wherein the acoustic radiation generator is in indirect contact with the quantity of the fluid.

Assignees

• Labcyte Inc
• Labcyte Inc

Inventors

• Stearns Richard G
• Hinkson Stephen J

Classifications

• G01N2035/1034

  Transferring microquantities of liquid · CPC title

• B05B17/06

  using ultrasonic {or other kinds of} vibrations · CPC title

• B01L3/0268 Primary

  using pulse dispensing or spraying, eg. inkjet type, piezo actuated ejection of droplets from capillaries · CPC title

• B01L2400/0415

  electrical forces, e.g. electrokinetic · CPC title

• G01N35/1009

  Characterised by arrangements for controlling the aspiration or dispense of liquids · CPC title