IP Library Granted Patent US 12,624,655
Granted Patent B2
US 12,624,655 · App. 18/929,378 · Granted May 12, 2026

Fuel bypass system for gaseous-fueled engine

Inventors: Steven W. Craig (Big Bend, WI); Andrew P. Sibrel (Oconomowoc, WI); Aaron J. Baska (Greenfield, WI); Douglas R. Clement (Wind Lake, WI)
Assignee: Generac Power Systems, Inc.
F02B29/0431F02B3/04F02B29/0418F02B29/0475F02D29/06F02D41/0007F02D41/061F02D19/02F02D19/023F02D41/0027F02D41/062F02M21/02F02M35/10163
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Quick Facts
Patent No.
US 12,624,655
App. No.
18/929,378
Granted
May 12, 2026
Kind
B2
Abstract

A method of operating a forced induction gaseous-fueled engine includes mixing gaseous-fuel and engine intake air to form a mixture at a fuel mixer. The method includes delivering the mixture to an intake manifold by at least partially bypassing a charge air cooler.

Claims (30)

1 . A method of operating a forced induction gaseous-fueled engine, the engine comprising a charge air cooler, a compression device, a throttle valve, an intake manifold, a bypass line, and a plurality of cylinders, the method comprising:

at least partially closing the throttle valve during a bypass period to deliver fuel during engine start through the bypass line to the intake manifold for delivery to the plurality of cylinders while bypassing the compression device, the charge air cooler, and the throttle valve, wherein the bypass line is upstream from an inlet of the compression device and an inlet of the charge air cooler and is downstream from the throttle valve.

2 . The method of claim 1 , wherein the fuel comprises a fuel-air mixture.

3 . The method of claim 1 , wherein the bypass line allows uncompressed fuel to flow via the bypass line to the intake manifold.

4 . The method of claim 1 , wherein the bypass period is a time interval determined by when the engine exceeds a predetermined RPM threshold.

5 . The method of claim 1 , further comprising opening the throttle valve an increasing amount during the bypass period.

6 . The method of claim 1 , further comprising closing the throttle valve when completely bypassing the charge air cooler and the compression device.

7 . The method of claim 1 , further comprising after bypassing the charge air cooler and the throttle valve, opening the throttle valve to transition to primary fuel system operation.

8 . The method of claim 1 , wherein the engine further comprises a bypass valve positioned in communication with the bypass line, and wherein the bypass valve is opened when completely bypassing the charge air cooler.

9 . The method of claim 8 , further comprising closing the bypass valve when the engine exceeds a predetermined RPM threshold.

10 . The method of claim 8 , further comprising opening the bypass valve for a predetermined bypass period time interval after an initiation of a starting sequence of the engine and closing the bypass valve after a bypass period time interval has elapsed.

11 . A fuel bypass arrangement for a forced induction gaseous-fueled engine, the fuel bypass arrangement comprising:

a bypass line;

a charge air cooler;

a throttle valve;

an intake manifold;

a compression device;

a plurality of cylinders; and

a controller configured to at least partially close the throttle valve while fuel is delivered during engine start through the bypass line to the intake manifold for delivery to the plurality of cylinders, bypassing the compression device, the charge air cooler, and the throttle valve, wherein the bypass line is upstream from an inlet of the compression device and an inlet of the charge air cooler and is downstream from the throttle valve.

12 . The fuel bypass arrangement of claim 11 , wherein the fuel is delivered directly to the intake manifold.

13 . The fuel bypass arrangement of claim 11 , wherein the fuel comprises a fuel-air mixture.

14 . The fuel bypass arrangement of claim 11 , wherein the bypass line allows uncompressed fuel to flow via the bypass line to the intake manifold.

15 . The fuel bypass arrangement of claim 14 , wherein the throttle valve is positioned between, and in fluid communication with, the charge air cooler and the intake manifold, wherein the throttle valve is configured to control an amount of fuel that is delivered to the intake manifold from the charge air cooler.

16 . The fuel bypass arrangement of claim 11 , further comprising a bypass valve in communication with the bypass line, the bypass valve being configured to selectively control the flow of the fuel through the bypass line.

17 . The fuel bypass arrangement of claim 16 , wherein the controller is in communication with the bypass valve and automatically opens the bypass valve at an initiation of a starting sequence of the engine.

18 . The fuel bypass arrangement of claim 11 , wherein after the fuel bypasses the charge air cooler and the throttle valve, the throttle valve is opened to transition to primary fuel system operation.

19 . A power backup system comprising a forced induction gaseous-fueled engine, the engine comprising:

a bypass line, a charge air cooler, a throttle valve, an intake manifold, a compression device, a plurality of cylinders, and a controller configured to at least partially close the throttle valve while fuel is delivered from a fuel source during engine start through the bypass line to the intake manifold for delivery to the plurality of cylinders, bypassing the compression device, the charge air cooler, and the throttle valve, wherein the bypass line is upstream from an inlet of the compression device and an inlet of the charge air cooler and is downstream from the throttle valve.

20 . The power backup system of claim 19 , further comprising an electricity generating system in communication with the engine, wherein an external electrical load is connected to the electricity generating system within 10 seconds from an initiation of a starting sequence of the engine.

21 . The power backup system of claim 19 , wherein the bypass line allows uncompressed fuel to flow via the bypass line to the intake manifold.

Assignments (2)
AFTER-ACQUIRED INTELLECTUAL PROPERTY SECURITY AGREEMENT (FOURTH SUPPLEMENTAL FILING) Recorded Jul 3, 2025
From: GENERAC POWER SYSTEMS, INC.
To: JPMORGAN CHASE BANK, N.A.
Reel/Frame 071824/0606 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded May 19, 2025
From: CRAIG, STEVEN W.; SIBREL, ANDREW P.; BASKA, AARON J.; CLEMENT, DOUGLAS R.
To: GENERAC POWER SYSTEMS, INC.
Reel/Frame 071156/0349 →
Continuity (6)
Continuation 18433168 · Feb 5, 2024
Continuation 18052517 · Nov 3, 2022
Continuation 17108514 · Dec 1, 2020
Continuation 16373791 · Apr 3, 2019
Provisional Application 62652186 · Apr 3, 2018
Related Publication 20250122824A1 · Apr 17, 2025
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