Prior art — US Patent 11492985

To identify the most relevant prior art for US patent 11492985, I will refer to the "Citations" section of the patent itself, as listed in the provided full patent text. This section explicitly lists the prior art documents cited by the examiner and/or third parties. For each listed patent, I will provide the requested details.

Here is an analysis of the prior art citations for US Patent 11492985:

Most Relevant Prior Art for US Patent 11492985

The following prior art documents are cited in US Patent 11492985. It's important to note that a definitive assessment of which claims are actually anticipated by which prior art would typically require a detailed claim-by-claim analysis, often performed during patent examination or litigation. However, based on the abstract and descriptions, potential areas of anticipation can be identified.

1. US4278064A

Full Citation: US4278064A, "Fuel control system for a dual-fueled power unit"
Publication/Filing Date: Publication: 1981-07-14; Priority/Filing: 1979-03-07
Brief Description: This patent describes a fuel control system for an engine capable of operating on two different fuels, such as gasoline and a gaseous fuel. It includes a carburetor and a system to control the flow of both liquid and gaseous fuels to the engine.
Potential Anticipation: This patent potentially anticipates aspects of claims related to dual-fuel operation and the general concept of controlling fuel flow from two sources to an engine. Specifically, it might be relevant to Claim 4 (dual fuel generator), Claim 5 (mechanical fuel valve for selective fuel flow), and Claim 14 (dual fuel generator) by showing a similar system for managing two fuel types.

2. US4463735A

Full Citation: US4463735A, "Dual fuel supply system"
Publication/Filing Date: Publication: 1984-08-07; Priority/Filing: 1983-06-02
Brief Description: This patent details a dual fuel supply system for an internal combustion engine, allowing it to run on either of two different fuels.
Potential Anticipation: Similar to US4278064A, this patent could anticipate elements of claims pertaining to dual fuel operation, particularly Claims 4, 5, 6, 14, 15, and 16, which cover the dual fuel generator aspect and the selective control of liquid and gaseous fuel sources.

3. US7591257B2

Full Citation: US7591257B2, "Fuel selection device"
Publication/Filing Date: Publication: 2009-09-22; Priority/Filing: 2006-09-07
Brief Description: This patent describes a fuel selection device for an engine, likely addressing the mechanism for switching between different fuel sources.
Potential Anticipation: This patent may be relevant to Claim 5 and Claim 15, which discuss a "mechanical fuel valve actuatable between a first position and a second position to selectively control fuel flow." It might also relate to Claim 6, which describes a "fuel lockout apparatus coupled to the mechanical fuel valve" for individual fuel source communication.

4. US20110168133A1

Full Citation: US20110168133A1, "Approach for controlling fuel flow with alternative fuels"
Publication/Filing Date: Publication: 2011-07-14; Priority/Filing: 2010-05-28
Brief Description: This publication describes an approach for controlling fuel flow when using alternative fuels, which is pertinent to dual-fuel systems.
Potential Anticipation: This could potentially anticipate aspects of all independent claims (1, 11, and 16) by disclosing methods or systems for managing alternative fuels in a generator or engine. Depending on the specifics of the fuel flow control, it could be particularly relevant to the regulation and delivery of gaseous fuel.

Additional Cited Patents (Brief Overview):

While a detailed analysis of each of the 41 cited patents is beyond the scope of this response, these examples illustrate the range of prior art considered. Many of the other cited patents also generally relate to:

Internal combustion engines and their improvements (e.g., GB189800A, GB532903A).
Multi-port or selector valves for fuel systems (e.g., US2398437A, US3911956A, US4287908A, US4471805A, US5555873A, US5934320A, US8042569B2, US9523497B2).
Dual fuel systems for various engines and vehicles (e.g., US4323046A, US4375795A, US4416244A, US4492207A, US6543395B2, US6591817B2, WO2007048633A1, US20070137591A1, EP1826377A2, US7802562B2, US20100258099A1, US7905469B2, US8757139B2, US8944027B2, US9175601B2).
Fuel injection and carburetion systems (e.g., US4750514A, US4788960A, JPH0466743A, US5611312A, CN2401704Y, US7954479B2).
Regulators and pressure control in fuel systems (e.g., US3412258A).

The examiner and inventors likely considered these references to define the novelty and non-obviousness of the "off-board fuel regulator" and "mechanical fuel lockout switch" aspects of US11492985, particularly the specific two-stage off-board regulation as claimed in claims 1, 11, and 16, and the interlock mechanism of claims 5, 6, and 15. The "generator free of any pressure regulator" as explicitly stated in Claim 1 is a distinguishing feature.