Leak-free, diffusion-blocking check valve, pump and method

Patent metadata

Field	Value
Publication number	US-12258952-B2
Application number	US-202318108384-A
Country	US
Kind code	B2
Filing date	Feb 10, 2023
Priority date	Feb 10, 2023
Publication date	Mar 25, 2025
Grant date	Mar 25, 2025

Abstract

A closed leak-free, diffusion-blocking one-way check valve is composed of a substrate having a flow passage through the substrate, the flow passage has a sealing surface between the substrate and a membrane preventing flow through the flow passage. A thin film having internal stress is disposed on the membrane which induces deformation of the membrane biasing the membrane resulting in the sealing surface in a closed orientation. A method for fabrication and pump utilizing the check valve are disclosed.

First claim

What is claimed:

1. A closed diffusion-blocking one-way flow check valve, comprising:
a flow passage in a one-way direction through the check valve from an inlet to an outlet;
a handle comprising the inlet on one side of the handle and a valve seat disposed on a side of the handle opposite the inlet side along the flow passage;
a membrane comprising a flap tethered to the membrane by a plurality of tethers and the outlet comprising an opening adjacent the plurality of tethers between the membrane and the flap, wherein the flap comprises a valve seat contacting area on one side of the flap and an intrinsically stressed biasing element disposed on a side of the flap opposite the valve seat contacting area; and
a spacer layer disposed between the handle and the membrane creating a portion of the flow channel between the handle valve seat and the flap valve seat contacting area, wherein the biasing element forces the valve seat contacting area of the flap against the valve seat of the handle biasing the check valve in a closed position relative to the flow passage.

2. The check valve of claim 1 , wherein the valve seat contacting area and the valve seat are optically flat silicon-to-silicon sealing surfaces.

3. The check valve of claim 1 , wherein the biasing element exerts a force sufficient to open the valve in response to an inlet pressure and an outlet pressure within a flow rate regime of from 1 nl/min to 5000 nl/min.

4. The check valve of claim 1 , wherein the biasing element is tuned to a film stress of from 10 MPa to 100 MPa.

5. The check valve of claim 1 , wherein the check valve has a diameter of less than 1 cm.

6. The check valve of claim 1 , wherein the check valve has a thickness of less than 5 mm.

7. The check valve of claim 1 , wherein the check valve has a thickness of less than 1 mm.

8. The check valve of claim 1 , wherein the handle is silicon, the membrane is silicon, the spacer later is silicon oxide and the biasing element is silicon nitride.

9. The check valve of claim 1 , wherein the check valve is tuned to an opening pressure of from 1.2 kPa to 2.9 kPa or from 220 kPa to 320 kPa.

10. A pump comprising:
a pump actuation membrane connected to an electrically operated heater disposed in a pump chamber of a flow channel between an inlet check valve comprising:
a flow passage in a one-way direction through the check valve from an inlet to an outlet;
a handle comprising the inlet on one side of the handle and a valve seat disposed on a side of the handle opposite the inlet side along the flow passage;
a membrane comprising a flap tethered to the membrane by a plurality of tethers and the outlet comprising an opening adjacent the plurality of tethers between the membrane and the flap, wherein the flap comprises a valve seat contacting area on one side of the flap and an intrinsically stressed biasing element disposed on a side of the flap opposite the valve seat contacting area; and
a spacer layer disposed between the handle and the membrane creating a portion of the flow channel between the handle valve seat and the flap valve seat contacting area, wherein the biasing element forces the valve seat contacting area of the flap against the valve seat of the handle biasing the check valve in a closed position relative to the flow passage

and an outlet check valve comprising:
a flow passage in a one-way direction through the check valve from an inlet to an outlet;
a handle comprising the inlet on one side of the handle and a valve seat disposed on a side of the handle opposite the inlet side along the flow passage;
a membrane comprising a flap tethered to the membrane by a plurality of tethers and the outlet comprising an opening adjacent the plurality of tethers between the membrane and the flap, wherein the flap comprises a valve seat contacting area on one side of the flap and an intrinsically stressed biasing element disposed on a side of the flap opposite the valve seat contacting area; and
a spacer layer disposed between the handle and the membrane creating a portion of the flow channel between the handle valve seat and the flap valve seat contacting area, wherein the biasing element forces the valve seat contacting area of the flap against the valve seat of the handle biasing the check valve in a closed position relative to the flow passage, wherein the pump is disposed in a cylinder.

11. The pump of claim 10 , wherein the inlet and outlet check valve biasing element exerts a force sufficient to open the respective valve in response to an inlet pressure and an outlet pressure within a flow rate regime of from 1 nl/min to 5000 nl/min.

12. The pump of claim 10 , wherein the inlet and outlet check valves each have a diameter of less than 1 cm.

13. The pump of claim 10 , wherein the inlet and outlet check valves each have a thickness of less than 5 mm.

14. The pump of claim 10 , wherein the inlet and outlet check valves each have a thickness of less than 1 mm.

Assignees

• Borkholder David A
• Forouzandeh Farzad
• Rochester Institute Tech

Inventors

• Borkholder David A
• Forouzandeh Farzad

Classifications

• F16K15/1441

  with biasing means in addition to material resiliency, e.g. spring · CPC title

• F16K99/0015

  Diaphragm or membrane valves · CPC title

• F04B19/006 Primary

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

• F04B43/043 Primary

  Micropumps · CPC title