Control system for the electric fuel pump of an internal combustion engine

• US 5,345,915 A
• Filed: 04/22/1993
• Issued: 09/13/1994
• Est. Priority Date: 10/10/1991
• Status: Expired due to Term

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Schmitz-Huebsch, Axel, Koelle, Ulrich, Flaetgen, Dietmar
• Primary Examiner(s): MILLER, CARL STUART
• Application Number:
  US08/039,356
• Time in Patent Office: 509 Days
• Field of Search: 123/497, 123/499, 123/198 D, 123/198 DB, 123/359
• US Class Current: 123/497
• CPC Class Codes: B60R 2021/0027 Post collision measures, e.g. notifying emergency services
• CPC Class Codes: F02D 41/222 relating to the failure of sensors or parameter detection devices
• CPC Class Codes: F02D 41/3082 Control of electrical fuel pumps
• CPC Class Codes: F02M 2037/085 Electric circuits therefor
• CPC Class Codes: F02M 37/08 electrically driven

Abstract

A control system is described for the electric fuel pump of an internal combustion engine, with a sensor for the speed of a shaft of the engine and with a logic circuit for providing a shut off signal for the pump, depending on the speed detected, where the signal of a further sensor (14) for the speed is supplied to the a logic circuit (16, 17), and where shut off then takes place only when both speed signals deviate from a specified range. In this way, it is ensured that the vehicle remains drivable if one of the two sensors (13) or (14) fails.

Claims

1. Control system for an electrically driven fuel pump of an internal combustion engine, said control system comprising first means for sensing a speed of a shaft of said engine, second means for sensing another speed, and logic means for generating a shut off signal for said fuel pump, said logic means being connected to both of said sensing means and having comparison means for generating said shut off signal so as to shut off said fuel pump only if both of said speeds sensed by both said first and second means deviate from a predetermined speed range but not to shut off said fuel pump if only one of said speeds sensed by only one of said means deviates from a predetermined speed range.

2. Control system as defined in claim 1, wherein said internal combustion engine has a crankshaft and a camshaft, and said first means for sensing a speed of a shaft of said engine detects a crankshaft speed of said engine and said second means for sensing another speed detects a camshaft speed of said engine.

3. Control system as defined in claim 1, wherein said logic means includes switching means for interrupting a flow of electricity to said electrically driven fuel pump if both of said speeds sensed by both said first and second means deviate from said predetermined speed range, and wherein said predetermined speed range is defined by a minimum and maximum speed value.

4. Control system as defined in claim 1, further comprising means for preventing said logic means from shutting off said fuel pump when said internal combustion engine is being started.