Multi-fuel engine control with fuel transition delay

• US 4,909,225 A
• Filed: 06/16/1989
• Issued: 03/20/1990
• Est. Priority Date: 06/16/1989
• Status: Expired due to Fees

• Current Assignee: Mitsubishi Petrochemical Co., Ltd. (Mitsubishi Chemical Group Corp.), General Motors Corporation (Motors Liquidation Co. GUC Trust), Unicharm Corporation
• Original Assignee: General Motors Corporation (Motors Liquidation Co. GUC Trust)
• Inventors: Brown, David B., Gonze, Eugene V.
• Primary Examiner(s): Cross, E. Rollins
• Application Number:
  US07/367,277
• Time in Patent Office: 277 Days
• Field of Search: 123/494, 123/478, 123/1 A, 123/575
• US Class Current: 123/494
• CPC Class Codes: F02B 1/04 with fuel-air mixture admission into cylinder
• CPC Class Codes: F02D 19/0605 to adjust the fuel pressure or temperature
• CPC Class Codes: F02D 19/084 Blends of gasoline and alcohols, e.g. E85
• CPC Class Codes: F02D 19/087 with determination of densities, viscosities, composition, concentration or mixture ratios of fuels
• CPC Class Codes: F02D 2200/0611 Fuel type, fuel composition or fuel quality
• CPC Class Codes: F02D 41/0025 Controlling engines characterised by use of non-liquid fuels, pluralities of fuels, or non-fuel substances added to the combustible mixtures
• CPC Class Codes: F02D 41/28 Interface circuits
• CPC Class Codes: Y02T 10/30 Use of alternative fuels, e.g. biofuels

Abstract

A fuel control for an engine using a liquid mixture of two fuels, such as gasoline and methanol, having different volumetric heat contents is responsive to a fuel compostion sensor to update a stored engine fuel control parameter. When a significant change in fuel composition is sensed, the stored engine fuel control parameter is not updated for a fuel transition time duration to allow the unchanged fuel still in the conduit between the sensor and engine to be used with the unchanged stored engine fuel control parameter.

Claims

1. A fuel control for a vehicle engine having a fuel tank with a liquid fuel mixture comprising first and second combustible fuels, a fuel conduit to the engine a fuel pump activated during engine operation to pump the fuel mixture from the fuel tank to the engine, a fuel composition sensor in the fuel conduit responsive to a physical parameter of the fuel mixture to generate a fuel composition signal indicative of the relative proportions of the first and second fuels in the fuel mixture, and means normally responsive to the fuel composition sensor during engine operation to repeatedly update a stored engine fuel control parameter in response to the fuel composition signal, the means normally responsive to the fuel composition signal being effective, in response to a predetermined change in the fuel composition signal, to delay updating of the stored engine fuel control parameter in response to the predetermined change for a fuel transition time duration substantially equal to the time required for the fuel pump to pump fuel from the fuel composition sensor to the engine.

2. The fuel control of claim 1 in which the fuel pump is operable to generate a variable fuel pressure and the fuel transition time duration is varied inversely with a parameter indicative of the fuel pressure.