Electronically controlled fuel injection arrangement for internal combustion engines

Claim 2

A fuel injection arrangement for internal combustion engines comprising, in combination, first monostable multivibrator means with pulse duration dependent upon an operating characteristic of said engine and determining partially the quantity of fuel being injected; second monostable multivibrator means connected to said first monostable multivibrator means and having a pulse duration dependent upon the pulse duration of said first monostable multivibrator means, the beginning of the pulse duration of Said second monostable multivibrator being controlled by said first monostable multivibrator; first temperature-sensing means operatively connected to said first monostable multivibrator means for influencing the pulse duration of said first monostable multivibrator means; and second temperature-sensing means operatively connected to said second monostable multivibrator means for influencing the pulse duration of said second monostable multivibrator means, whereby the quantity of fuel injected is determined by the combined pulse durations of said first and second monostable multivibrator means, said pulse durations being dependent on said operating characteristic of said engine and on temperatures sensed by said first and second temperature-sensing means.

Claim 3

The fuel injection arrangement as defined in claim 1 wherein said first and second temperature-sensing means are subjected to two different temperatures varying with a time constant different from each other by a factor of five.

Claim 4

The fuel injection arrangement as defined in claim 2 wherein said first temperature-sensing means is influenced by temperature variations of substantially small time constant, said first temperature-sensing means applying a correction of 60 to 80 percent to the injection duration in which fuel is injected; and wherein said second temperature-sensing means is influenced by temperature variations of substantially longer time constant, said second temperature-sensing means applying a correction to said injection duration within the range of 20 to 40 percent.

Claim 5

The fuel injection arrangement as defined in claim 1 wherein said temperature-sensing means are temperature dependent resistors.

Claim 6

The fuel injection arrangement as defined in claim 1 wherein the pulse duration of said second monostable multivibrator means exceeds proportionately an increase in the pulse duration of said first monostable multivibrator means within at least a portion of the region of said pulse durations.

Claim 7

The fuel injection arrangement as defined in claim 5 wherein the pulse duration of said second monostable multivibrator means is equal to the pulse duration of said first monostable multivibrator means multiplied by a factor b minus a second factor a.

Claim 8

The fuel injection arrangement as defined in claim 1 including capacitor means in said second monostable multivibrator means and being charged during the time interval of the pulse duration of said first monostable multivibrator means, said capacitor means being discharged at the end of the pulse duration of said first monostable multivibrator means, the pulse duration of said second monostable multivibrator means being dependent upon the charged voltage on said capacitor means.

Claim 9

The fuel injection arrangement as defined in claim 7 including a constant current source for charging said capacitor means.

Claim 10

The fuel injection arrangement as defined in claim 8 wherein said constant current source comprises a transistor.

Claim 11

The fuel injection arrangement as defined in claim 1 including a timing network controlled by said first monostable multivibrator means; and discharge circuit means in said second monostable multivibrator means influenced by said timing network.

Claim 12

The fuel injection arrangement as defined in claim 10 wherein said timing network influences said discharge circuit of said second monostable multivibrator means for rapid discharging within a predetermined time interval at the end of the pulse duration of said first monostable multivibrator means.

Claim 13

The fuel injection arrangement as defined in claim 7 including a voltage source connected to said monostable multivibrator means for providing operating voltage; and means for influencing the discharge of said capacitor means as a function of said operating voltage so that the pulse duration of said second monostable multivibrator means is decreased with increase in said operating voltage.

Claim 14

The fuel injection arraNgement as defined in claim 12 including a timing network controlled by said first monostable multivibrator means; and discharge circuit means in said second monostable multivibrator means influenced by said timing network, said discharge circuit in said second monostable multivibrator means being influenced by the operating voltage of said monostable multivibrator means only when said timing network is operative, said operating voltage for said monostable multivibrator means being applied by a source of voltage.

Claim 15

The fuel injection arrangement as defined in claim 13 including a transistor connected to said capacitor means; emitter resistor means connected in series with the emitter of said transistor; voltage-dividing means having a tap connected to the base of said transistor, said voltage-dividing means being connected to said operating voltage of said voltage source; diode means connected to the emitter of said transistor; a Zener diode connected to said diode means and in parallel with said emitter resistor means so that the part of the discharge current from said capacitor means flowing through said Zener diode increases above a proportionately increase in said operating voltage.

Claim 16

The fuel injection arrangement as defined in claim 14 including second resistor means connected between said diode means and said Zener diode.

Claim 17

The fuel injection arrangement as defined in claim 7 including means for discharging said capacitor means so that the discharge is a function of the temperature of said engine, whereby the discharged time is decreased with increase in the temperature of said engine.

Claim 18

The fuel injection arrangement as defined in claim 16 including a transistor in said means for discharging said capacitor; a source of voltage supply; a voltage divider connected across said source of voltage supply and having a tap connected to the control electrode of said transistor; an auxiliary voltage divider connected across said source of voltage and including a temperature dependent resistor thermally coupled to said engine; a diode connected between a tap of said first voltage divider and a tap of said auxiliary voltage divider so that the conductivity of said transistor decreases below a predetermined temperature of said engine.

Claim 19

The fuel injection arrangement as defined in claim 17 including additional voltage-dividing means connected across said source of voltage; and an additional diode connected between a tap of said auxiliary voltage-dividing means and a tap of said additional voltage-dividing means so that said additional diode conducts when said temperature dependent resistor attains a predetermined resistance value at low temperatures, whereby further decrease in the conductivity of said transistor in inhibited.

Claim 20

The fuel injection arrangement as defined in claim 7 including discharge circuit means for discharging said capacitor means; and starting switching means operatively connected to said discharge means for increasing the discharge time of said capacitor means when said switching means is in operative closed-circuit state.

Claim 21

The fuel injection arrangement as defined in claim 19 including a transistor in said discharge circuit means; a source of operating voltage; a voltage divider connected across said source of operating voltage and having a tap connected to the control electrode of said transistor, and means for connecting said switching means parallel with a portion of said voltage-dividing means so that the conductivity of said transistor decreases when said switching means is in operative closed-circuit state.

Claim 22

The fuel injection arrangement as defined in claim 18 including starting switching means connected in parallel with a portion of said first voltage-dividing means, said additional diode being nonconductive when said switching is in operative closed-circuit state.

Claim 23

The fuel injection arrangement as defined in claim 1 wherein said operating characteristic of said engine is the pressUre within the intake manifold of said engine.

Claim 24

The fuel injection arrangement as defined in claim 4 wherein said temperature dependent resistor means comprises resistor means with negative temperature coefficient.

Claim 25

A fuel injection arrangement for internal combustion engines comprising, in combination, first monostable multivibrator means with pulse duration dependent upon an operating characteristic of said engine and determining partially the quantity of fuel being injected; second monostable multivibrator means connected to said first monostable multivibrator means and having a pulse duration dependent upon the pulse duration of said first monostable multivibrator means, the beginning of the pulse duration of said second monostable multivibrator being controlled by said first monostable multivibrator; first temperature-sensing means operatively connected to said first monostable multivibrator means for influencing the pulse duration of said first monostable multivibrator means; and second temperature-sensing means operatively connected to said second monostable multivibrator means for influencing the pulse duration of said second monostable multivibrator means, whereby the quantity of fuel injected is determined by the pulse durations of said first and second monostable multivibrator means, said first temperature-sensing means being thermally coupled to the cooling water of said internal combustion engine, said second temperature-sensing means being thermally coupled to the oil flow circuit of said engine.

Claim 26

A fuel injection arrangement for internal combustion engines comprising, in combination, first monostable multivibrator means with pulse duration dependent upon an operating characteristic of said engine and determining partially the quantity of fuel being injected; second monostable multivibrator means connected to said first monostable multivibrator means and having a pulse duration dependent upon the pulse duration of said first monostable multivibrator means, the beginning of the pulse duration of said second monostable multivibrator being controlled by said first monostable multivibrator; first temperature-sensing means operatively connected to said first monostable multivibrator means for influencing the pulse duration of said first monostable multivibrator means; and second temperature-sensing means operatively connected to said second monostable multivibrator means for influencing the pulse duration of said second monostable multivibrator means, whereby the quantity of fuel injected is determined by the pulse durations of said first and second monostable multivibrator means, said first temperature-sensing means being thermally coupled to the cooling water of said internal combustion engine, said second temperature-sensing means being thermally coupled to the oil flow circuit of said engine.

Claim 27

A fuel injection arrangement for internal combustion engines comprising, in combination, first monostable multivibrator means with pulse duration dependent upon an operating characteristic of said engine and determining partially the quantity of fuel being injected; second monostable multivibrator means connected to said first monostable multivibrator means and having a pulse duration dependent upon the pulse duration of said first monostable multivibrator means, the beginning of the pulse duration of said second monostable multivibrator being controlled by said first monostable multivibrator; first temperature-sensing means operatively connected to said first monostable multivibrator means for influencing the pulse duration of said first monostable multivibrator means; and second temperature-sensing means operatively connected to said second monostable multivibrator means for influencing the pulse duration of said second monostable multivibrator means, whereby the quantity of fuel injected is determined by the pulse durations of said first and second monostable multivibrator means, said first temperature-sensing means being arranged on the cylinder head of said internal combustion engine, said second temperature-sensing means being arranged in the oil flow circuit of said engine.

Claim 28

A fuel injection arrangement for internal combustion engines comprising, in combination, first monostable multivibrator means with pulse duration dependent upon an operating characteristic of said engine and determining partially the quantity of fuel being injected; second monostable multivibrator means connected to said first monostable multivibrator means and having a pulse duration dependent upon the pulse duration of said first monostable multivibrator means, the beginning of the pulse duration of said second monostable multivibrator being controlled by said first monostable multivibrator; first temperature-sensing means operatively connected to said first monostable multivibrator means for influencing the pulse duration of said first monostable multivibrator means; and second temperature-sensing means operatively connected to said second monostable multivibrator means for influencing the pulse duration of said second monostable multivibrator means, whereby the quantity of fuel injected is determined by the pulse durations of said first and second monostable multivibrator means, said first temperature-sensing means being arranged on the cylinder head of said internal combustion engine, said second temperature-sensing means being arranged in the oil flow circuit of said engine.