US 4,058,106 A · Method and apparatus for RPM limitation in internal combustion engines

Abstract

The maximum speed of an internal combustion engine is limited by a device which compares the period of rpm-synchronous pulses with the time constant of a reference multivibrator. If the engine rpm is so high that a pulse terminates prior to expiration of the reference time period, a gate is activated and acts through further multivibrator circuits to interrupt the fuel delivery to the engine, e.g., the fuel injection control pulses are suppressed. If the maximum rpm is exceeded only intermittently, the device restores normal fuel injection control pulses after a predetermined number of pulses has been suppressed. If the maximum rpm is exceeded continuously, the device restores normal fuel control somewhat later than the time at which the engine speed drops to below maximum rpm.

Claims16

Dependent claims

A method for limiting the rpm in an internal combustion engine, said engine including fuel preparation means, comprising the steps of:

interrupting fuel supply for a predetermined period of time after the engine has reached a predeterminable limiting rpm;
and
suppressing all fuel supply when the limiting rpm of the engine is exceeded and continuing to suppress all fuel supply for a predetermined time after the engine rpm has again dropped below the limiting rpm.

An apparatus for rpm-limitation in an internal combustion engine, said engine including fuel preparation and metering means, comprising:

a first monostable multivibrator, triggered by rpm-synchronous pulses supplied by the engine, the time constant of said first multivibrator defining a reference time period;
an AND gate whose one input is connected to receive the output of said first multivibrator and whose second input is connected to receive directly said rpm-synchronous signal;
a second monostable storage multivibrator, triggered by said AND gate;
and
a third monostable multivibrator, controlled by said second monostable multivibrator, and connected to said fuel preparation means for suppressing fuel control signals therefrom.

2 more elements

Dependencies are inferred from the claim text.

Method and apparatus for RPM limitation in internal combustion engines

Life of this patent

Method and apparatus for RPM limitation in internal combustion engines

Life of this patent

Abstract

Claims16