FUEL INJECTION SYSTEM FOR INTERNAL COMBUSTION ENGINES

• US 3,797,465 A
• Filed: 06/24/1971
• Issued: 03/19/1974
• Est. Priority Date: 07/04/1970
• Status: Expired due to Term

• Current Assignee: Nobuhito Hobo, Norio Omori
• Original Assignee: Nobuhito Hobo, Norio Omori
• Inventors: Hobo, Nobuhito, Omori, Norio
• Primary Examiner(s): Goodridge, Laurence M.
• Application Number:
  US05/156,439
• Time in Patent Office: 999 Days
• Field of Search: 123/32EA,32AE,139E,139,179HG
• US Class Current: 123/357
• CPC Class Codes: F02D 2250/38 Control for minimising smoke emissions, e.g. by applying smoke limitations on the fuel injection amount
• CPC Class Codes: F02D 41/38 of the high pressure type

Abstract

A fuel injection system for internal combustion engines is disclosed, in which there are provided fuel injection patterns for engine starting and for full-load engine operations. Cold starting of the engine is facilitated by injecting fuel according to the fuel injection control pattern required by the engine at the time of starting, and once after the engine has been started or when engine has been warmed up the fuel injection is made according to the fuel control pattern required for full-load operation, so that no black smoke generates even if the engine is rotated at a low speed with the full-load, thereby ensuring optimum fuel supply over the entire engine speed and engine load ranges without sacrificing the engine output for full-load operation of the engine.

Claims

1. A fuel injection system for internal combustion engines comprising:

circuit means for generating an engine starting control voltage, said control voltage varying according to the fuel control pattern required for cold starting of an engine, said engine starting control voltage being relatively high for low engine speeds, circuit means for generating a full-load engine operating control voltage, said control voltage varying according to the fuel control pattern required for a full-load operation of the engine, said full-load control voltage being relatively low for high engine speeds, wherein as the speed of said engine increases to full-load operation, said engine starting control voltage decreases to said full-load control voltage, a selecting circuit responsively coupled to each of said aforementioned circuit means for selecting the higher one of the control voltages generated by said control voltage generating circuit means, a monostable timing pulse generator connected to said selecting circuit for providing timing pulses having a pulse duration corresponding to the selected control voltage, and a fuel injection pump responsive to sAid timing pulses having an electromagnetic valve to control the quantity of fuel discharged from said fuel injection pump in each cycle thereof in accordance with the pulse duration of the timing pulse delivered from the timing pulse generator, said engine starting control voltage generating means including means for changing the control voltage in response to a selected condition of engine operation.

2. The fuel injection system of claim 1 wherein said engine starting control voltage generating circuit means includes means for generating the control voltage in accordance with two preset control patterns, namely, a first higher voltage pattern and a second lower voltage pattern, and means for selecting the control voltage of said first voltage pattern in response to an engine cranking condition only.

3. The fuel injection system of claim 1 wherein said engine starting control voltage generating circuit means includes means for generating the control voltage in accordance with two preset control patterns, namely, a first higher voltage pattern and a second lower voltage pattern, and means for selecting the control voltage of said higher voltage pattern in accordance with a cold engine condition only.

4. The fuel injection system of claim 1 wherein said engine starting control voltage generating circuit means includes means for varying the control voltage of the control pattern to be changed in response to an instantaneous engine temperature condition.

5. The fuel injection system of claim 2 wherein said engine starting control voltage generating circuit means includes, means for changing each control voltage of both the higher and lower voltage patterns in response to an instant engine temperature condition.