Microfluidic valve

Patent metadata

Field	Value
Publication number	US-11209102-B2
Application number	US-201415111361-A
Country	US
Kind code	B2
Filing date	Jan 29, 2014
Priority date	Jan 29, 2014
Publication date	Dec 28, 2021
Grant date	Dec 28, 2021

Abstract

A microfluidic valve comprises a first reservoir, a second reservoir, an inertial pump and a channel connecting the first reservoir to the second reservoir. The second reservoir is to receive fluid from the first reservoir through the channel under a pressure gradient. The inertial pump is within the channel proximate the second reservoir and distant the first reservoir.

First claim

What is claimed is:

1. A microfluidic valve comprising:
a first reservoir;
a second reservoir;
a channel connecting the first reservoir to the second reservoir, wherein the second reservoir is to receive fluid from the first reservoir through the channel under a pressure gradient from the first reservoir to the second reservoir in the channel, the pressure gradient to drive a first flow of the fluid into the channel from the first reservoir to the second reservoir; and
an inertial pump within the channel proximate the second reservoir and distant the first reservoir the inertial pump to drive a second flow of the fluid from the second reservoir to the first reservoir in the channel that opposes the first flow caused by the pressure gradient in the channel, and to thereby operate as a microfluidic valve and to control fluid flow between the first reservoir and second reservoir in the channel to:
occlude the first flow of the fluid from the first reservoir to the second reservoir; or
reduce a rate of the first flow of the fluid caused by the pressure gradient from the first reservoir to the second reservoir.

2. The valve of claim 1 , wherein the inertial pump comprises a bubble jet pump to generate a bubble that pushes the fluid in the channel toward each end of the channel and thereby cause the second flow of the fluid that opposes the first flow of the fluid caused by pressure gradient.

3. The valve of claim 1 further comprising an actuator to selectively vary a spacing of the inertial pump from the second reservoir and wherein the inertial pump is distant from an input of the first flow of the fluid into the channel from the first reservoir to the second reservoir.

4. The valve of claim 1 further comprising:
a second inertial pump within the channel proximate the second reservoir and distant the first reservoir; and
an actuator to selectively actuate the inertial pump and the second inertial pump to generate the second flow of the fluid that opposes the first flow of the fluid.

5. The valve of claim 4 comprising an array of independently actuatable firing resistors forming the inertial pump and the second inertial pump, wherein the firing resistors of the array are differently spaced from the second reservoir.

6. The valve of claim 1 comprising an array of independently actuatable firing resistors forming the inertial pump, the resistors of the array being equally spaced from the second reservoir, wherein the actuator comprises a controller to selectively fire the resistors to varying number of the resistors that are actuated to vary a pumping force.

7. The valve of claim 1 further comprising an actuator to selectively vary a pumping force of the inertial pump at a given location.

8. The valve of claim 1 , wherein the channel comprises:
a first branch;
a second branch extending from an intersection with the first branch; and
a third branch extending from the intersection and connected to a third reservoir.

9. The valve of claim 8 further comprising an actuator to selectively vary one of a pumping force of the inertial pump at a given location and a location of the inertial pump.

10. The valve of claim 8 further comprising:
a second inertial pump within the third branch proximate the third reservoir and distant the intersection; and
an actuator to independently vary pumping of the inertial pump and the second inertial pump.

11. The valve of claim 10 further comprising a third inertial pump within the first branch, wherein the actuator is to independently vary pumping of the first inertial pump, the second inertial pump and the third inertial pump.

12. The valve of claim 1 , wherein the second reservoir has a cross-sectional area at a junction of the second reservoir and the channel of at least 10 times a cross-sectional area of the channel at the junction, and further comprising a pump coupled to the channel to generate the pressure gradient and drive the first flow of the fluid.

13. The microfluidic valve of claim 1 further comprising:
a third reservoir, wherein the channel comprises a first branch extending from the first reservoir, a second branch extending from the second reservoir and a third branch extending from the third reservoir, the first branch, second branch and the third branch connecting at an intersection;
a second inertial pump, wherein the inertial pump and the second inertial pump are within the second branch proximate the second reservoir and distant the intersection;
a third inertial pump and a fourth inertial pump, wherein the third inertial pump and the fourth inertial pump are within the first branch proximate the first reservoir and distant the intersection;
a fifth inertial pump and a sixth inertial pump, wherein the fifth inertial pump and the sixth inertial pump are within the third branch proximate the third reservoir and distant the intersection; and
an actuator to selectively activate the first inertial pump, a second inertial pump, the third inertial pump, the fifth inertial pump and the sixth inertial pump to control fluid flow to and from each of the first reservoir, a second reservoir and the third reservoir.

14. The microfluidic valve of claim 13 , wherein the inertial pump and the second inertial pump are equally spaced from the second reservoir, wherein the third inertial pump and the fourth inertial pump are equally spaced from the first reservoir and wherein the fifth inertial pump and the sixth inertial pump are equally spaced from the third reservoir.

15. The microfluidic valve of claim 13 further comprising:
a fourth reservoir, where the channel comprises a fourth branch extending from the fourth reservoir and connected to the intersection; and
a seventh inertial pump and an eighth inertial pump within the fourth branch proximate the fourth reservoir and distant the intersection, wherein the actuator is further to selectively actuate the seventh inertial pump and the eighth inertial pump to control fluid flow to it from the fourth reservoir.

16. The microfluidic valve of claim 1 further comprising a second inertial pump in the channel proximate the first reservoir and distant the second reservoir to pump fluid towards the second reservoir which forms the pressure gradient, the inertial pump to drive the second flow of the fluid that occludes the first flow of the fluid from the first reservoir to the second reservoir.

17. A microfluidic valving method comprising:
applying a pressure gradient from a first reservoir to a second reservoir to bias a first fluid flow from the first reservoir to the second reservoir through a channel connecting the first reservoir to the second reservoir, the pressure gradient being in the channel and driving the first fluid flow; and
selectively actuating an inertial pump within the channel proximate the second reservoir and distant the first reservoir, and thereby, generating a second fluid flow from the second reservoir to the first reservoir in the channel that opposes the first fluid flow in the channel caused by the pressure gradient, so as to control the fluid flow, the inertial pump to drive the second fluid flow from the second reservoir to the first reservoir in the channel to:
occlude the first fluid flow from first reservoir to the second reservoir; or
reduce a rate of the first fluid flow caused by the pressure gradient from the first reservoir to the second reservoir.

18. The method of claim 17 comprising selectively varying one of a pumping force of the inertial pump at a given location and a location of the inertial pump to control

Assignees

• Hewlett Packard Development Co

Inventors

• Govyadinov Alexander
• Torniainen Erik D
• Kornilovich Pavel
• Markel David P

Classifications

• F04B19/006 Primary

  Micropumps (F04B43/043 and F04B43/095 take precedence) · CPC title

• F04B19/24

  Pumping by heat expansion of pumped fluid · CPC title

• F16K99/0019 Primary

  Valves using a microdroplet or microbubble as the valve member · CPC title

• F05B2210/11

  liquid, i.e. incompressible · CPC title

• F04B43/04 Primary

  Pumps having electric drive · CPC title