# US 10,864,535 B2 · Avoidance of bouncing and splashing in droplet-based fluid transport > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,864,535 B2 - Document ID: US10864535B2 - Status: Granted - Kind: B2 - Application number: 16/135,337 - Filed: 2018-09-19 - Published: 2019-05-30 - Granted: 2020-12-15 - Earliest claimed: 2005-03-14 - Assignees: Labcyte Inc. - Applicants: Labcyte Inc. - Inventors: Richard G. Stearns; Stephen J. Hinkson - Web page: https://patentgrep.com/patent/US10864535B2 ## CPC - B05B 5/005: {the high voltage supplied to an electrostatic spraying apparatus being adjustable during spraying operation, e.g. for modifying spray width, droplet size} - B01L 3/0268: {using pulse dispensing or spraying, eg. inkjet type, piezo actuated ejection of droplets from capillaries} - B05B 17/06: using ultrasonic {or other kinds of} vibrations - G01N 35/1009: {Characterised by arrangements for controlling the aspiration or dispense of liquids} - G01N 35/1074: {arranged in a two-dimensional array} - B01L 2300/0819: Microarrays; Biochips - B01L 2300/0829: Multi-well plates; Microtitration plates - B01L 2400/027: electrostatic forces between substrate and tip - B01L 2400/0415: electrical forces, e.g. electrokinetic - B01L 2400/0436: acoustic forces, e.g. surface acoustic waves [SAW] - B01L 2400/0487: fluid pressure, pneumatics - G01N 2035/1034: {Transferring microquantities of liquid} - Y10T 436/2575: Volumetric liquid transfer - B05B: SPRAYING APPARATUS; ATOMISING APPARATUS; NOZZLES (spray-mixers with nozzles B01F25/72; processes for applying liquids or other fluent materials to surfaces by spraying B05D) - B01L: CHEMICAL OR PHYSICAL LABORATORY APPARATUS FOR GENERAL USE - G01N: INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES (measuring or testing apparatus or processes other than immunoassay, involving enzymes or microorganisms C12M, C12Q) - Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION ## 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. ## Claims ### Claim 1 A system for fluid transport comprising: a reservoir containing a quantity of the fluid, a droplet generator configured to acoustically radiate the reservoir to generate a droplet from the fluid in the reservoir, a controller coupled to the droplet generator and configured to control the operation of the droplet generator, a target arranged to receive the generated droplet, and a circuit configured to generate an electric field in a space between the reservoir and the target, wherein the generated electric field alters a velocity of the generated droplet, wherein the altered velocity of the generated droplet increases the likelihood that the generated droplet will not splash or bounce on arriving at the target. ### Claim 2 (depends on 1) The system of claim 1, wherein the circuit is configured to generate the electric field to be non-negligible at a free surface of the fluid in the reservoir. ### Claim 3 (depends on 2) The system of claim 2, wherein the circuit is configured to generate the electric field to have a magnitude between 1000 and 100,000 V/m at the free surface of the fluid in the reservoir. ### Claim 4 (depends on 1) The system of claim 1, wherein the circuit comprises an electrode positioned and configured to generate the electric field between the reservoir and the target. ### Claim 5 (depends on 1) The system of claim 1, wherein the circuit is configured to generate the electric field to causes a droplet generated by the droplet generator to be electrically charged. ### Claim 6 (depends on 4) The system of claim 4, wherein the electrode is configure to be held at a predetermined voltage for a predetermined period of time. ### Claim 7 (depends on 1) The system of claim 1, wherein the controller is further configured to control the circuit and to vary the electric field generated by the circuit over time. ### Claim 8 (depends on 1) The system of claim 1, wherein the circuit is configured to generate the electric field such that the generated electric field does not cause a droplet generated by the droplet generator to deviate from a path the generated droplet would travel in the absence of the generated electric field. ### Claim 9 (depends on 1) The system of claim 1, wherein the circuit is further configured to control a magnitude of the electric field based on an external input. ### Claim 10 (depends on 9) The system of claim 9, wherein the circuit is further configured to switch the magnitude of the electric field between a predetermined value for a predetermined time and zero based on the external input. ### Claim 11 (depends on 1) The system of claim 1, wherein the circuit comprises a charging device arranged and configured to charge some or all of the target. ### Claim 12 (depends on 1) The system of claim 1, wherein the altered velocity is within a range of velocities predetermined to increase the likelihood that the generated droplet will not splash or bounce on arriving at the target. ### Claim 13 (depends on 12) The system of claim 12, wherein the predetermined range of velocities lies within the range of 1.0 to 2.5 m/s. ### Claim 14 (depends on 1) The system of claim 1, wherein the altered velocity causes a Weber number of the generated droplet to be within a predetermined range. ### Claim 15 (depends on 1) The system of claim 1, wherein the target is positioned relative to the reservoir so that the generated droplet 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. ### Claim 16 (depends on 1) The system of claim 1, wherein the droplet generator is nozzleless. ### Claim 17 (depends on 1) The system of claim 1, wherein the droplet generator does not make contact with the fluid in order to generate a droplet.