JPS58167835A - Fuel injection device - Google Patents

Abstract

PURPOSE:To prevent a stop of an enging, by switching the operation from individual cylinder injection to full cylinder simultaneous injection when a reference cylinder signal is not detected in a fail-safe device used for a fuel injection device of the internal-combustion engine. CONSTITUTION:4-bit binary counters 1, 2 are provided, and a signal Ref from a crank angle sensor is input to a Reset terminal of the counter 1 through an inverter 3. A POS signal required for control of an engine speed and ignition timing and a 180 deg. signal REF are respectively input to CLOCK and Reset terminals of the counter 1. A reference signal is obtained by AND operation between output terminals Q0, Q1 of the counter 2. When the reference cylinder signal is not detected and/or continuously detected, the operation is witched to full cylinder simultaneous injection to prevent an engine from stopping.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a fuel injection device using a microcomputer-controlled fuel injection system, and more particularly to a fail-safe function for cylinder-specific fuel injection.

Conventional microcomputer-controlled cylinder-specific fuel injection systems have no fail-safety when detecting a reference cylinder signal, and if the reference cylinder signal is not detected or is detected continuously, only certain cylinders are injected. The fuel was being injected, which caused the engine to stop rotating, causing severe damage to the engine itself.

The present invention provides a fuel injection system which causes negative effects on the engine when the reference cylinder signal is not detected or is detected continuously.

In order to achieve such an objective, the present invention provides a software-based 721 signal in the microcomputer open-cylinder fuel injection system when the reference cylinder signal is not detected or is detected continuously. This system is equipped with a safety function, and is configured to switch from cylinder-specific injection to all-cylinder injection depending on the engine.

The present invention will be described in detail below using Examples.

FIG. 1 is a circuit diagram showing an embodiment of the reference cylinder detection circuit used in the fuel injection device according to the present invention. ◎4b11 binary up counters 1 and 2 are round;
It Binary Up Counter 10Reset The Vc is set so that the signal (Rel) from the crank angle sensor is manually input via the inverter 3t. In addition, each output of CLOCK-11 child Q-, Q* is NAND circuit 11
Manual power is applied to the Enab16 terminal of the same counter via r4. The output of the output terminal Q is input to the AND circuit W15 together with the output of the output terminal Qo, and the output of the AND circuit W15 is 4bt.
The output from the output terminal Q+ of the 1-pine rear counter 2 is inverted by an inverter and then input to the other input terminal of the AND circuit 6, and the output of the AND circuit 6 is taken out as a reference cylinder signal. It looks like this.

Next, the operation of the reference cylinder detection circuit configured in this way will be explained in a second manner.
This will be explained below using figures.

PE signal (PO8) necessary for engine speed and ignition timing control
signal) and 180 @ signal (REF number: among these, the wide-circled pulse is generated by the n* cylinder signal), respectively, the Clock child of 4b Ropinary up counter 1 and Re5e.
When the L11Ii1 child is manually input, the gi number shown in Figure 2 (5) is manually input to the Re5et 1m child of the binary up counter 2 at the next stage. Output terminal Q0 of 4-bit binary up counter 2. Q.
), the bond shown in (8) is output, and the AN of Qo and Q is
By taking Dt, the 211th (
A signal of 9J is output.

This signal of $I21m (9) is sent to the microcomputer-controlled fuel injection system as a reference cylinder signal. Side 3 is an operation flowchart of the microcomputer to which the reference cylinder signal is input.

In the third part, Inrtial interrupt is an interrupt when the signal of the reference signal for ignition timing ([211(4) and below 1nitial signal) is input to the micro comviator control system.
This is a program that performs 1Ill of K11L injection every 1 st+.

By providing the counters 1 and 2 after the WIJ to determine the reference cylinder, the aggrogram switches to full-cylinder injection when the reference cylinder signal no longer rises or is triggered manually.

Therefore, according to the present invention, when the j&semi-cylinder signal is not detected or when it is detected jIa, all cylinders lW
The situation 11 in which the engine stops rotating due to switching to l# injection can be avoided.

As is clear from the above description, according to the present invention,
If the reference cylinder signal is no longer detected or is detected continuously in the microcomputer-controlled cylinder-specific fuel injection system, the 7-work safety function will prevent the system from switching from cylinder-specific injection to all-injection simultaneous injection. Therefore, there is an effect that fI411 can be solved from the state of Rka in which the engine stops rotating (9).

A simple ill on the AA side! #llll1lI is a configuration diagram showing an example of the reference cylinder 4111 output ago used in the fuel injection device according to the present invention, and Fig. 2 is a main construction diagram showing the operation waveforms of each part of the reference cylinder detection circuit. 1 is a chart showing the operation of a microcomputer to which the output of the cylinder detection circuit is input.

1.2...4bxt Binary up counter, 3.
7...Inverter, 4...Nand road, 5.6...
・AND circuit.

Claims (1)

[Claims] 1. A fuel injection valve is provided for each cylinder, and a reference cylinder detection circuit determines the timing of fuel injection according to the rotation of the internal combustion engine,
In a fuel injection device that injects fuel into each cylinder, when either the reference cylinder signal is not detected or the reference cylinder signal is detected continuously, switching from individual cylinder injection to simultaneous injection in all cylinders is provided. Fuel injection device with % mold.