Method and system for adjusting pressure in a fuel tank

Patent metadata

Field	Value
Publication number	US-12460607-B2
Application number	US-202318532672-A
Country	US
Kind code	B2
Filing date	Dec 7, 2023
Priority date	Dec 7, 2023
Publication date	Nov 4, 2025
Grant date	Nov 4, 2025

Abstract

Methods and systems for diagnosing an evaporative emissions system are discussed. An example method includes diagnosing a venturi pump of an evaporative emissions system based on feedback from an evaporative leak check module (ELCM) pressure sensor and a fuel tank pressure transducer (FTPT). An engine of a vehicle is off during the diagnosing.

First claim

The invention claimed is:

1 . A hybrid vehicle system, comprising:
an engine; a plurality of canisters arranged in series; an evaporative leak check module (ELCM) comprising a changeover valve (COV) and arranged between atmosphere and a downstream canister in series of the plurality of canisters; a venturi pump arranged in a load line extending from a fuel tank to an upstream canister of the plurality of canisters, the venturi pump comprising a low-pressure port fluidly coupled to the ELCM, a first port fluidly coupled to the load line, and a second port fluidly coupled to the load line; a pressure sensor arranged between the ELCM and the downstream canister; a fuel tank pressure transducer (FTPT) arranged between the venturi pump and the fuel tank; and a controller with computer-readable instructions stored on memory thereof that when executed cause the controller to: execute a diagnostic of the venturi pump in response to the engine being off and a fuel tank pressure being greater than or equal to a threshold pressure via closing the COV, and opening a plurality of bypass valves, each of the plurality of bypass valves corresponding to each of the plurality of canisters.

2 . The hybrid vehicle system of claim 1 , wherein the instructions further enable the controller to indicate the diagnostic is passed in response to the pressure sensor sensing a negative pressure and the FTPT sensing a decaying fuel tank pressure.

3 . The hybrid vehicle system of claim 1 , wherein the instructions further enable the controller to indicate the diagnostic is not passed in response to the pressure sensor sensing a non-negative pressure.

4 . The hybrid vehicle system of claim 3 , wherein the instructions further enable the controller to adjust one of a depressurization rate of the fuel tank, a refueling fill rate of the fuel tank, and a reverse purging of the upstream canister in response to the diagnostic not being passed.

5 . The hybrid vehicle system of claim 1 , wherein the plurality of canisters further comprises a canister arranged between the upstream canister and the downstream canister.

Assignees

• Ford Global Tech Llc

Inventors

• Dudar Aed

Classifications

• F02M25/0836 Primary

  Arrangement of valves controlling the admission of fuel vapour to an engine, e.g. valve being disposed between fuel tank or absorption canister and intake manifold · CPC title

• F04F5/20

  for evacuating · CPC title

• F02M25/0818

  having means for pressurising the evaporative emission space · CPC title

• F02M25/0809 Primary

  Judging failure of purge control system · CPC title

• F02D2041/225

  Leakage detection · CPC title