Prior art — US Patent 11840970

Analysis of Prior Art for U.S. Patent 11,840,970

Report Date: May 13, 2026

This analysis details the most relevant prior art cited during the examination of U.S. Patent 11,840,970, titled "Dual fuel generator with remote regulator." The key inventive concept of patent '970 appears to be a dual fuel generator system where the gaseous fuel pressure regulation system, particularly a two-stage regulator, is located "off-board" or remote from the generator housing, leaving the generator itself free of such regulators. A mechanical valve on the generator is used to select the fuel type.

The following references were cited by the USPTO examiner and are evaluated for their potential to anticipate the claims of patent '970 under 35 U.S.C. § 102.

1. US 2007/0137591 A1

Full Citation: US Patent Application Publication No. 2007/0137591 A1
Assignee: Honda Motor Co., Ltd.
Publication Date: June 21, 2007
Filing Date: September 29, 2004
Description: This publication discloses an engine-operated generator capable of using both gasoline and a gaseous fuel such as LPG. It describes a fuel-switching mechanism to select between the two fuel sources. The system includes a pressure regulator (vaporizer) for the gaseous fuel. However, the architecture described and depicted in the figures (e.g., Fig. 1) shows the vaporizer/regulator unit mounted directly onto the generator's frame or housing. It does not teach or suggest a fuel regulator system that is intentionally located "off board" the generator.
Potential Anticipation: This reference is relevant as it teaches a dual-fuel generator. However, it does not appear to anticipate the key claims of patent '970. The core limitation requiring the fuel regulator system to be "off board" and the generator to be "free of any pressure regulator mounted within the generator housing" (as recited in claims 1, 12, 20, 34, and 44 of '970) is not disclosed. In '591, the regulator is part of the generator assembly itself. Therefore, this reference would likely fail to anticipate these claims.

2. US 2011/0168133 A1

Full Citation: US Patent Application Publication No. 2011/0168133 A1
Assignee: Ford Global Technologies, LLC
Publication Date: July 14, 2011
Filing Date: May 28, 2010
Description: This document describes a dual fuel system for an internal combustion engine, primarily in an automotive context. It details a method for controlling fuel flow when switching between a liquid fuel (gasoline) and an alternative fuel (like CNG or LPG). The system includes pressure regulators to deliver the gaseous fuel to the engine at a suitable pressure. The focus of the invention is on the control logic for smooth fuel transition rather than the physical placement of the components. The document does not discuss a portable generator, nor does it teach the specific configuration of an "off-board" or remote, two-stage regulator system separate from the main engine assembly.
Potential Anticipation: This reference is unlikely to anticipate the claims of patent '970. Its teachings are directed at automotive systems, not portable generators. Crucially, it does not disclose the claimed spatial relationship of a generator that is "free from any gaseous fuel pressure regulator" being supplied by a distinct "off board" fuel regulator system. The claims of '970 are specific to the generator system's architecture, which is not addressed by '133.

3. US 11,530,654 B2

Full Citation: U.S. Patent No. 11,530,654 B2
Assignee: Champion Power Equipment, Inc.
Publication Date: December 20, 2022
Filing Date: November 15, 2018 (This application is a continuation of the same parent application as '970)
Description: This patent, from the same assignee and part of the same family as '970, is titled "Off-board fuel regulator for generator engine." It explicitly describes and claims a dual fuel generator system where the fuel regulator for the gaseous fuel is located off-board the generator. It discloses a primary and secondary pressure regulator configured to be mounted on or near the pressurized fuel source (e.g., an LPG tank) and connected to the generator via a hose. This arrangement leaves the generator housing free of a gaseous fuel regulator.
Potential Anticipation: This patent is highly relevant and discloses many of the same features as patent '970. As a related patent within the same family, it shares a common specification. While it describes the same fundamental system, its claims may be directed to slightly different aspects of the invention. However, the disclosure is substantively the same. For the purpose of a novelty analysis under 35 U.S.C. § 102, this patent would likely anticipate or, at a minimum, render obvious many of the claims in patent '970, depending on the specific claim language and priority dates. For instance, its core teaching of an off-board dual-stage regulator directly maps onto the primary limitations of independent claims 1, 12, 20, 34, and 44 of patent '970. The distinction between the patentability of the claims in '654 versus '970 would rely on subtle differences in claim scope established during prosecution.