# US 11,306,839 B1 · Double poppet check valve for low and high flow rates

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 11,306,839 B1
- Document ID: US11306839B1
- Status: Granted
- Kind: B1
- Application number: 17/099,891
- Filed: 2020-11-17
- Granted: 2022-04-19
- Earliest claimed: 2020-11-17
- Applicants: Merrill Manufacturing Company
- Inventors: Stephen J. Anderson
- Web page: https://patentgrep.com/patent/US11306839B1

## CPC

- F16K 15/066: {with a plurality of valve members}
- F16K 17/30: spring-loaded
- F16K 15/026: {the valve member being a movable body around which the medium flows when the valve is open}
- F16K 15/028: {the valve member consisting only of a predominantly disc-shaped flat element}
- F16K 17/0473: {Multiple-way safety valves}
- Y10T 137/7841: One valve carries head and seat for second valve
- F16K: VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING {(devices for emptying and evacuating the excess liquid in valves or conduits F16L55/07)}
- Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION

## Abstract

A poppet-style check valve comprising a small poppet and a large poppet. When low flow rates are required, the small poppet opens and permits the low flow rate to pass efficiently. When demand for flow increases, the large poppet opens, permitting efficient passage of higher flow rates.

## Claims

### Claim 1

A double poppet check valve comprising:
a double poppet check valve body;
an inlet port by which a fluid enters the double poppet check valve;
a discharge port by which a fluid exits the double poppet check valve;
a small poppet permitting the passage of the fluid from the inlet port to the discharge port;
a large poppet permitting the passage of the fluid from the inlet port to the discharge port;
a large poppet head;
a large poppet seat disposed in the large poppet head;
a large poppet stem;
a broad side of the large poppet stem;
a narrow side of the large poppet stem, wherein the narrow side is narrower than the broad side;
an aperture in the large poppet head, said aperture having a diameter greater than a width of the narrow side of the large poppet stem;
a shoulder inside the large poppet stem;
a large poppet spring disposed about the large poppet stem;
a small poppet head fitted to the large poppet seat;
a small poppet stem disposed in the aperture in the large poppet head and through a second aperture formed by the shoulder inside the large poppet stem; and
a small poppet spring disposed about the small poppet stem;
a first pressure coefficient at which the small poppet opens fully; and
a second pressure coefficient, not equal to the first pressure coefficient, at which the large poppet opens fully.

### Claim 2 (depends on 1)

The double poppet check valve of claim 1 wherein the first pressure coefficient is less than the second pressure coefficient.