Original Publication Date: 1991-Feb-01
Included in the Prior Art Database: 2005-Apr-01
Lunde, DM: AUTHOR [+2]
This article describes an engine control system which maintains an internal combustion (IC) engine revolutions per minute (RPM) at a set value when a load is removed.
describes an engine control system which
maintains an internal combustion (IC) engine revolutions per minute
(RPM) at a set value when a load is removed.
Conventionally, revolution limiting tachometers are used to
limit engine revolutions which use only preset RPM limits. The
system disclosed herein provides better protection against engine
damage/destruction when a load is removed by using an RPM limit to
retard the engine spark, but not cut it off. Then, individual spark
signals are eliminated. If the RPM is still over limit, the spark is
cut off entirely. This concept is progressive RPM limiting.
the figures, Fig. 1 is a block diagram of the
system disclosed herein. Fig. 2 shows the timing of the operation.
The system uses a three-step process to limit engine speed as
1. When the engine reaches the preset limit, the ignition timing
will be retarded.
2. If RPM still climbs with timing retarded, the system will
randomly eliminate individual spark signals.
3. If RPM still climbs, the last mode will shut the ignition
completely off until RPM falls back into range.
limit RPM is programmed by reving the engine to its
limit or one-half limit and pushing a set switch.
also will accept a signal from an oil pressure gauge
sender or switch and will cut ignition if oil pressure goes below 20
psi. This system will allow ignition on ...