U.S. patent application number 09/759131 was filed with the patent office on 2001-09-27 for motor control method and apparatus for internal combustion engine.
Invention is credited to Ganser, Thomas, Koch, Charles Robert, Lauffer, Dietmar, Maute, Kurt, Schmidt, Andreas, Stalitza, Markus, Wehle, Johannes.
Application Number | 20010023679 09/759131 |
Document ID | / |
Family ID | 7627328 |
Filed Date | 2001-09-27 |
United States Patent
Application |
20010023679 |
Kind Code |
A1 |
Ganser, Thomas ; et
al. |
September 27, 2001 |
Motor control method and apparatus for internal combustion
engine
Abstract
In a motor control method and apparatus for an internal
combustion engine, a point for the beginning of injection moment
and injection period for each cylinder are determined in a
load-controlled way in a motor controller and supplied to the
actuators for execution of the injection. To improve the response
characteristic of the internal combustion engine, control
information for injection of the cylinder currently to be addressed
is transmitted as reserve information for the subsequent cylinder
in every transmission cycle. In the event of a load increase,
reserve information from the previous transmission cycle is used to
control injection in the subsequent cylinder.
Inventors: |
Ganser, Thomas; (Wernau,
DE) ; Koch, Charles Robert; (Remseck/Pattonville,
DE) ; Lauffer, Dietmar; (Herzogenaurach, DE) ;
Maute, Kurt; (Sindelfingen, DE) ; Schmidt,
Andreas; (Muehlacker, DE) ; Stalitza, Markus;
(Schwaebisch Gmuend, DE) ; Wehle, Johannes;
(Moeglingen, DE) |
Correspondence
Address: |
Evenson, McKeown, Edwards & Lenahan, P.L.L.C.
1200 G Street, N.W., Suite 700
Washington
DC
20005
US
|
Family ID: |
7627328 |
Appl. No.: |
09/759131 |
Filed: |
January 16, 2001 |
Current U.S.
Class: |
123/406.47 ;
123/478 |
Current CPC
Class: |
F02D 41/10 20130101;
Y02T 10/44 20130101; F02D 2250/12 20130101; Y02T 10/40 20130101;
F02D 13/0253 20130101; F02D 41/345 20130101; F02D 41/266 20130101;
F02D 2041/001 20130101 |
Class at
Publication: |
123/406.47 ;
123/478 |
International
Class: |
F02P 005/15; F02M
051/00 |
Foreign Application Data
Date |
Code |
Application Number |
Jan 13, 2000 |
DE |
100 01 062.8 |
Claims
What is claimed is:
1. A method for controlling an internal combustion engine in which
a motor controller determines an injection point and injection
period for internal combustion engine cylinders in crank angle
synchronous transmission cycles, as a function of a load acting on
the internal combustion engine, and transmits the determined
injection point and injection period to actuators that are assigned
to the cylinders, as a control data set for execution of an
injection, wherein: for every transmission cycle in the control
data set, said controller transmits control information for
injection of a cylinder currently to be addressed, and reserve
information for injection of a cylinder to be addressed in the
following transmission cycle; and at least said reserve information
is saved for at least one transmission cycle; in a stable running
mode, control information from a current transmission cycle is used
for fuel injection into the cylinder currently to be addressed, and
one of current control information and reserve information from the
current transmission cycle overwrites reserve information from a
previous transmission cycle; and upon the occurrence of a load
increase that increases injection periods in such a significant way
that, in terms of time, injection start in the cylinder currently
to be addressed would come before start of a current transmission
cycle, reserve information from a next preceding transmission cycle
is used for injection of the current cylinder.
2. The method according to claim 1, wherein if a load increase
occurs when reserve information is being used for a current
cylinder, simultaneously, a new control data set with control
information concerning a next following cylinder and reserve
information for a next to next following cylinder is generated and
transmitted.
3. The method according to claim 1, wherein upon occurrence of a
load reduction such that the injection start for the current
cylinder falls into a subsequent transmission cycle, substantially
constant control information and constant reserve information are
transmitted in successive control data sets to a cylinder currently
to be addressed, in at least two successive transmission
cycles.
4. The method according to claim 3, wherein constant control
information and constant reserve information in the control data
set are transmitted to a particular cylinder until an injection
point for the particular cylinder falls into the same transmission
cycle as a current transmission of control information.
5. The method according to claim 1, wherein injection start is
adjusted in a load-controlled way, whereby injection takes place
earlier in the event of a load increase, while injection takes
place later in the event of a load reduction.
6. The method according to claim 1, wherein the control data set
contains additional actuating variables with regard to internal
combustion engines.
7. The method according to claim 6, wherein the additional
actuating variables include at least one of actuating variables for
ignition and operation of variably adjustable gas shuttle
valves.
8. The method according to claim 1, wherein an opening moment of
variably adjustable gas shuttle valves is changed.
9. The method according to claim 1, wherein electro-magnetically
operable gas shuttle valves are used.
10. The method according to claim 1, wherein the control data set
is generated in a motor controller and transmitted to at least one
valve control unit.
11. A control device for an internal combustion engine, comprising
a motor controller for load-controlled determination of a control
data set for an injection point and an injection period for
internal combustion engine cylinders, said control data set being
supplied to actuators assigned to cylinders of the internal
combustion engine in crank angle synchronous transmission cycles,
wherein: the control data set generated in the motor controller
contains control information for injection of a cylinder currently
to be addressed and reserve information for injection of a cylinder
to be addressed in a next successive transmission cycle; at least
one valve control unit is provided, to which the control data set
from the motor controller can be supplied and in which actuating
signals for the actuators concerned with injection can be generated
from the control data set that has been received; the at least one
valve control unit includes a memory unit in which at least reserve
information of the control data set can be saved; and control
signals supplied to the valve control unit are generated such that
in a stable running mode, control information from a current
transmission cycle is used for determining actuating signals for
the actuators concerned with injection, and reserve information
from the current transmission cycle overwrites reserve information
from the previous transmission cycle in the memory unit, and upon
occurrence of a load increase which increases injection periods in
such a significant way that, in terms of time, the injection start
in the cylinder currently to be addressed would come before start
of a current transmission cycle, reserve information for injection
of the current cylinder, stored in the memory unit, is used for
determining actuating signals.
12. The control device according to claim 11, wherein one valve
control unit is assigned to each row of cylinders of the internal
combustion engine.
Description
BACKGROUND AND SUMMARY OF THE INVENTION
[0001] This application claims the priority of German patent
document 100 01 062.8, filed Jan. 13, 2000, the disclosure of which
is expressly incorporated by reference herein.
[0002] The present invention is directed to a motor control method
and apparatus for an internal combustion engine.
[0003] A controller of this generic type is described in German
patent document DE 196 27 280 A1. Its function is to control both
fuel injection and ignition for each cylinder by generating a
pulsed control signal. In crank angle synchronous combustion
cycles, control data sets are generated in the controller taking
into account the load at the internal combustion engine: injection
time increases with an increase in the load, generating a larger
motor torque, and decreases with a reduction in the load. The
generated control signals are supplied to those actuators and
components that adjust ignition and injection of each cylinder. The
various cylinders of the internal combustion engine are supplied in
successive cycles with the control data sets for injection and
ignition.
[0004] In this context, the problem can arise that with high loads
or greatly increasing loads, injection time increases to such an
extent that, within one working cycle of the internal combustion
engine, the time period available for data transmission and
injection of fuel into a cylinder is insufficient. As a result,
injection time must be limited to a value which is smaller than the
theoretical optimum. An increase of the time period for injection
to the target value can only be achieved in a later transmission
cycle; this, however, results in delayed power build-up which the
driver perceives as a poor response characteristic of the internal
combustion engine. In idle running for instance, the power build-up
of the internal combustion engine reacting to the load increase
with a delay can result in "stalling" the engine if a load increase
suddenly occurs, since the engine cannot respond quickly enough to
the load demand.
[0005] One object of the invention is to improve the response
characteristic of internal combustion engines in the event of load
changes.
[0006] This and other objects and advantages are achieved by the
motor control method and apparatus according to the invention,
which provides that in every new transmission cycle a control data
set containing both control information for injection of the
cylinder currently to be addressed, and reserve information for
injection of the cylinder to be addressed in the following cycle is
generated in the motor controller. During every transmission cycle,
the control data set generated in the motor controller is
transmitted to the actuators of the corresponding cylinder which
carry out the injection, or to a valve control unit controlling
these actuators.
[0007] The twofold transmission of control information--for the
cylinder that is currently addressed and for the following
cylinder--has the advantage that during every transmission cycle,
control information for two successive cylinders is provided; this
offers the possibility, particularly in case of a load increase,
that the subsequent cylinder can fall back on the reserve
information that is generated and transmitted in the previous
transmission cycle for controlling the injection. This technique
ensures that in the event of a load increase accompanied by a
longer injection period per transmission cycle, a longer time
period is available for injection because the cylinder can fall
back on reserve information transmitted and saved in the previous
cycle, if necessary, so that the window of time available for
injection for the corresponding (following) cylinder is enlarged.
As a result, in the event of a load increase, control information
originating from the directly preceding cycle is immediately
available. This reduces the time needed for adjusting to the
current load to a minimum and significantly improves the response
characteristic of the internal combustion engine.
[0008] If the internal combustion engine runs in a stable mode,
however, with a load that remains essentially constant, the
cylinders currently to be addressed are provided with current
control information. Reserve information that is generated and
transmitted at the same time is saved without being actually used
in stable running mode, since it is intended exclusively to define
injection data of the subsequent cylinder in the event of a load
increase with a greatly increasing injection period.
[0009] In accordance with a useful further development, the
procedure provides that in the event of a load increase, the
cylinder to be addressed currently receives reserve information
from the previous transmission cycle; simultaneously, a new set of
control data is generated by the motor controller that contains
control information for the next following cylinder and reserve
information for the next to next cylinder. This procedure ensures
that, synchronous with the fixed crank angle, a control data set is
generated and transmitted, the control information contained in the
control data set being a function of the load. For changes towards
higher loads and correspondingly longer injection time periods, two
successive control data sets contain control information for a
total of four successive cylinders; in this case, distribution
logic ensures that the first cylinder is first provided with
current control information of the first control data set; that the
following cylinder is provided with reserve information of the
first control data set; that the subsequent cylinder is then
provided with the current control information of the second control
data set; and that finally, the cylinder following thereafter is
provided with reserve information of the second control data set.
Thus it is ensured that each cylinder is provided with information
for any type of load situation.
[0010] In particular, the data sets contain cylinder specific
information regarding lambda control, cylinder deactivation,
electronic spark control, etc.
[0011] In a stable running mode, during which a sufficiently long
time period is available in every transmission cycle for generation
and transmission as well as for injection into a current cylinder,
two successive control data sets contain control information for a
total of three successive cylinders. First, the first cylinder is
provided with current control information of the first control data
set while reserve information is saved. In the following cycle, the
following cylinder is provided with current control information of
the second control data set while reserve information of the second
control data set intended for the next to next cylinder is stored
in a memory unit and overwrites the reserve information from the
previous control data set.
[0012] For a load reduction, if the start of fuel injection into
the current cylinder falls into a later transmission cycle due to
the decreased injection period, control information and reserve
information that are essentially constant in successive control
data sets are transmitted to the cylinder currently to be addressed
in at least two successive transmission cycles, thus constituting
an advantage. The control data set that is newly generated in every
transmission cycle remains essentially constant over at least two
successive transmission cycles until the moment for injecting fuel
into the cylinder currently to be addressed falls into the
transmission cycle of the control data set. This procedure ensures
that, even in the event of a significant load decrease accompanied
by a significant reduction of the injection period, the cylinder
currently to be addressed is provided with control information
assigned to this cylinder.
[0013] In accordance with the invention, the motor control device
includes a motor controller in which, in a load-controlled way,
control data sets are generated with control information and
reserve information. It also includes at least one valve control
unit communicating with the motor controller to which a memory unit
is assigned in which reserve information from the control data set
can be saved for at least one transmission cycle. In stable running
mode, the current control information from the control data set is
provided to the actuators for the cylinder currently to be
addressed; the reserve information transmitted with the current
control data set is stored in the memory unit of the valve control
unit, whereby the reserve information from the current transmission
cycle overwrites information from the previous cycle. In the event
of a load increase, however, the cylinder currently to be addressed
is not provided with current control information but with reserve
information from the previous transmission cycle.
[0014] Both the procedure in accordance with the invention and the
control device in accordance with the invention are suited for use
with variably adjustable gas shuttle valves, particularly
electro-magnetically operable gas shuttle valves, for which the
opening moment can purposely be varied as a function of the
injection period. Air supply, injection values and advantageously
also ignition data are preferably controlled by means of the valve
control unit to ensure that all control data are generated and
transmitted consistently.
[0015] Other objects, advantages and novel features of the present
invention will become apparent from the following detailed
description of the invention when considered in conjunction with
the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] FIG. 1 is a conceptual block diagram which shows the
structure of the motor control device according to the
invention;
[0017] FIG. 2 is a graphic depiction of an injection and combustion
cycle of a cylinder, recorded over crank angle synchronous ignition
intervals;
[0018] FIG. 3 is a flow chart which shows the procedural steps to
be taken in the control device for load-controlled adjustment of
injection moment and injection period;
[0019] FIG. 4 is a graphic depiction of cylinder addressing with
injection start and injection period assigned to each individual
cylinder, recorded over crank angle synchronous ignition intervals;
and
[0020] FIG. 5 is another flow chart which shows the procedural
steps to be taken in the control device for load-controlled
adjustment of injection moment and injection period according
to
DETAILED DESCRIPTION OF THE DRAWINGS
[0021] The motor control device (1) according to FIG. 1 includes a
motor controller (2) and two valve control units (3) and (4); each
of the valve control units is assigned to a cylinder bench of an
internal combustion engine, particularly of an Otto engine. In the
motor control device (2), control data sets are generated which are
supplied to valve control units (3) and (4) in crank angle
synchronous time intervals through communication lines (5) in form
of a CAN data bus. For crank angle dependent control, a crank angle
signal is transmitted to both motor controller (2) and valve
control units (3) and (4). In the valve control units (3) and (4)
which each are assigned to a cylinder bench of the internal
combustion engine, the control data sets received from the motor
controller (2) are transformed into actuating signals which are
supplied to actuators for controlling gas shuttle valves, injection
and ignition of each cylinder.
[0022] FIG. 2 shows a schematic depiction of the injection and
combustion cycle of a cylinder represented by crank angle
synchronous ignition intervals. A transmission cycle (i) for
generating and transmitting a control data set in the motor
controller or from motor controller to valve control unit takes
place between each of those intervals. FIG. 2 represents the
situation for an eight-cylinder engine for which the ignition
interval is 90.degree..
[0023] The whole injection and combustion cycle of a cylinder
within a working cycle of the internal combustion engine is divided
into a first time period t.sub.BU during which calculation and
transmission of the control data set is carried out, a time period
t.sub.VE during which injection is prepared and a time period
t.sub.E during which the actual injection of fuel into the cylinder
combustion chamber takes place. There might be a time gap,
characterized as t.sub.Tol, between the end moment when calculation
and transmission of the control data set is finished and the start
moment for preparing injection, representing a tolerance gap in the
injection and combustion cycle of a cylinder. The injection period
t.sub.E decreases or increases as a function of the load acting on
the internal combustion engine. Specifically, the starting point of
injection is varied, while the end point remains constant. The
injection period can be extended until the tolerance interval
t.sub.Tol has been completely used up; particularly in case of
significant load increases, it can also fall into the first time
period t.sub.BU.
[0024] According to the flow chart in FIG. 3, in a first procedural
step (6), a control data set is generated in the motor controller;
this control data set contains control information with regard to
injection, ignition and control of gas shuttle valves. Each control
data set includes a double set of control information: current
control information for an internal combustion engine cylinder to
be addressed in the current transmission cycle (i) and reserve
information intended for the next following cylinder in the
following transmission cycle (i+1). The two information sets are
intended for load cycle (i), both are identical.
[0025] In procedural step (7), an inquiry takes place to find out
if, due to an increased load demand, the injection start for the
cylinder currently to be addressed in transmission cycle (i) would,
in terms of time, occur before the start of the current
transmission cycle (i). If this is not so, the inquiry proceeds
along the NO branch to procedural steps (8) through (11). If, on
the other hand, this is the case the injection period determined as
a function of the load would exceed the time period that is
available (graphically indicated by the time spans t.sub.Tol,
t.sub.VE, and t.sub.E in FIG. 2), so that in the current
transmission cycle (i) an injection of fuel into this cylinder
cannot take place with the determined current control information;
in this case, the inquiry proceeds along the YES branch to
procedural steps (12) and (13).
[0026] Procedural steps (8) through (11), which are taken in case
the NO branch is selected at procedural step (7), represent either
a load condition that is essentially stable or a load decrease. In
this case, injection in the cylinder currently to be addressed is
carried out with control information from the control data set of
the current transmission cycle (i). A further inquiry according to
procedural step (8) first verifies whether due to load reduction
the injection start falls into a later transmission cycle (i+1). In
this case, the inquiry proceeds along the YES branch to procedural
step (9); the same cylinder with control information from the
existing control data set of transmission cycle (i) is addressed
again in the following transmission cycle (i+1).
[0027] The inquiry according to procedural step (8) is repeated
until the injection start falls into the current transmission
cycle; when this occurs, the inquiry proceeds along the NO branch
to the following procedural step (10) according to which the
control data set is transmitted to the valve control unit, and
subsequently in step (11), injection takes place using control
information of the control data set generated in transmission cycle
(i) Furthermore, in procedural step (11) current reserve
information of the transmission cycle (i) overwrites saved reserve
information from the previous transmission cycle (i-1).
[0028] In the event that a load increase is identified in
procedural step (7), the inquiry proceeds along the YES branch from
procedural step (7) to procedural step (12), according to which the
control data set generated in step (6) is transmitted to the valve
control unit. According to this YES branching, the injection start
occurs before the current transmission cycle (i) starts so that
injection in the cylinder currently to be addressed cannot be
performed with the control information from the control data set
generated. In this case, according to procedural step (13), the
cylinder falls back on the reserve information saved from the
previous transmission cycle (i-1) which represents the load
condition existing during the transmission cycle immediately
preceding the current one; this load condition from the previous
cycle corresponds to a shorter injection period. The injection
process can be started in the current transmission cycle (i) with
reserve information from the previous transmission cycle (i-1).
[0029] After proceeding through procedural steps (8) through (11)
or (12) and (13), the inquiry returns to procedural step (6); in a
subsequent transmission cycle a new control data set for the next
following cylinder is generated.
[0030] FIG. 4 shows cylinder addressing of successive cylinders 1
through 8 of an internal combustion engine as a function of crank
angle synchronous time intervals; whereby each transmission cycle
takes place between two successive moments marked by vertical lines
in FIG. 4. In ascending order from bottom left to top right the
representation shows the individual injection periods, each marked
with a black bar, for each individual cylinder; the cylinders are
identified on the right side of each bar. On the left side of each
bar, the assigned control data set characterized by two figures is
recorded with the letter "" marking the transmission of each data
set.
[0031] In the diagram of FIG. 4, the internal combustion engine
initially has a stable load condition. During transmission cycle
i=3 (i.e. within the two vertical lines to the left and right of
number "3" in FIG. 4) a load increase takes place, while during
transmission cycle i=5 of the following working cycle, a load
decrease takes place; then, the internal combustion engine runs in
a stable mode again.
[0032] During the first transmission cycle i=1, cylinder 4 is
addressed with control data set "45"; this control data set is
transmitted in the first transmission cycle i=1. Cylinder 4 is
addressed with the current control information "4"; this process is
marked graphically by the underlined number "4" in control data set
"45". The reserve information of this control data set marked "5"
is saved in a memory unit of the valve control unit while reserve
information from the previous transmission cycle is overwritten.
Reserve information "5" is assigned to the next following cylinder
5.
[0033] In the following transmission cycle i=2, a control data set
"56" is generated and transmitted, injection of cylinder 5 is
performed with the control information "5", and reserve information
"6" for the next following cylinder 6 overwrites reserve
information "5" from the previous transmission cycle (i-1). The
transition from addressing cylinder 4 to addressing cylinder 5 is
characterized by a stable running mode of the internal combustion
engine; the injection period is the same for the two cylinders.
[0034] The injection period of the next following cylinder 6 which
is supplied with control information "6" of a transmitted control
data set "67" also corresponds to the injection times of the two
previous cylinders. In the current transmission cycle i=3 which is
assigned to this cylinder 6, a load increase marked by a vertical
line takes place triggering a longer injection period.
[0035] In the next following cylinder 7 to be addressed in
transmission cycle i=4, no control data set can be transmitted
since creation and generation of a new control data set assigned to
this cylinder cannot take place within the time available for
calculation, transmission and injection. For that reason, the
cylinder falls back on reserve information "7" which is marked with
an underscore and originates from the previous transmission cycle
i=3 for addressing cylinder 7. The injection period provided in the
reserve information corresponds exactly to the injection period
provided in the corresponding control information of transmission
cycle i=3; since it originates from the previous cycle, the
injection period for cylinder 7 is identical to the one of the
previous cylinder despite the increase in load demand which has
taken place in the meantime.
[0036] At the same time that cylinder 7 is addressed with reserve
information from the previous transmission cycle i=3, a new control
data set "81" is generated and transmitted in the current
transmission cycle i=4. The new control data set "81" contains
current control information "8", with which the current cylinder 8
can be addressed, and reserve information "1" for the following
cylinder 1. The current control data set "81" now takes the load
increase into account and increases the injection period
accordingly with regard to the previous cylinders to be addressed.
However, the increase in the time period available for injection
has been selected in a way that the injection start can be begun in
the current transmission cycle i=4.
[0037] A continuous increase of the injection period takes place
between transmission cycle i=4 of the current working cycle and the
following transmission cycle i=4 assigned to the next working cycle
of the internal combustion engine; whereby for each transmission
cycle i=4, 5, 6, etc. one cylinder is supplied with reserve
information of the immediately preceding transmission cycle while
the following cylinder is supplied with current control information
of the currently transmitted control data set.
[0038] In transmission cycle i=4 of the following working cycle of
the internal combustion engine, a sudden, significant load
reduction takes place resulting in a correspondingly significant
shortening of the injection period. In the next transmission cycle
i=5 in which control data set "56" is generated and transmitted and
which is assigned to cylinder 5 currently to be addressed, it has
been noticed that the injection start of cylinder 5 does not take
place in the currently running transmission cycle i=5 but in a
later transmission cycle. As a result, in the following
transmission cycle i=6, the same control data set "56" is used
again for addressing cylinder 5; this process is repeated until the
injection start of the cylinder currently to be addressed falls
into the currently running transmission cycle; this is the case in
the model for transmission cycle i=2. The injection of cylinder 5
now takes place using control information "5" of control data set
"56" with the injection start falling into transmission cycle
i=2.
[0039] In the following process, a stable mode with constant
injection times for the subsequent cylinders sets in. Accordingly,
a control data set is generated and transmitted for each new
cylinder to be addressed using current control information of the
control data set from the current transmission cycle for injection
in each instance.
[0040] The increase and reduction in load demand can be implemented
in any order and without delay.
[0041] FIG. 5 represents another model in accordance with the
invention. In a first procedural step (14), a control data set is
generated by means of the load of cycle (i), whereby the control
data set contains parameters for ignition, injection and valve
control edges or valve control times. The injection start for cycle
(i) is determined as described hereinafter.
[0042] First, an inquiry is carried out in procedural step (15) to
determine if the injection start of the current cycle (i), in terms
of time, falls into a time period which comes after expiration of
the time periods t.sub.BU, t.sub.Tol and t.sub.VE (see FIG. 2) of
the current cycle (i); whereby in the first period of time t.sub.BU
calculation and transmission of the control data set take place and
in time period t.sub.VE injection is prepared whereas time period
t.sub.Tol characterizes a tolerance interval. If the time periods
t.sub.BU, t.sub.Tol and t.sub.VE have already expired, the inquiry
proceeds along the YES branch to procedural step (19) according to
which a control data set with control information for the cycle
(i+1) and further control or reserve information for a cycle (i+2)
are transmitted. In the ensuing procedural step (22), the injection
process is carried out or triggered provided that the control
information or reserve information have not been overwritten by
means of re-triggering. For cylinder (i+1), triggering of the
injection process takes place using control information of the
control data set, whereas for cylinder (i+2) reserve information is
used. After transmission and triggering of the injection process,
index "i" characterizing the cycle is increased by the value 2;
then, the process returns to step (14) to begin the procedure.
[0043] If in the inquiry after step (15) it is determined that, in
terms of time, the injection start precedes expiration of time
periods t.sub.BU, t.sub.Tol and t.sub.VE, the inquiry proceeds
along the NO branch of this procedural step to procedural step (16)
where another inquiry is performed to specify the injection start.
In procedural step (16), inquiry is performed as to whether, in
terms of time, the injection start comes before the beginning of
time periods t.sub.B, t.sub.Tol and t.sub.VE of cycle (i-1). If
this is so, the inquiry proceeds along the YES branch to procedural
steps (17) and (20). In this case, control information for cycle
(i-1) and control or reserve information for cycle (i) are
transmitted (procedural step 17). In the following procedural step
(20), the injection process is triggered with control information
for cylinder (i-1) and with reserve information for cylinder (i).
In case of the left procedural branch with procedural steps (17)
and (20) (injection start comes before the time periods t.sub.BU,
t.sub.Tol and t.sub.VE of cycle (i-1)), after transmission of
control information and triggering of the injection process, index
"i" is not increased but kept at the current level, and at that
level the entire procedure starting with procedural step (14) is
run through again.
[0044] If the injection start does not come after the time periods
t.sub.B, t.sub.Tol and t.sub.VE of cycle (i) and not before the
time periods t.sub.BU, t.sub.Tol and t.sub.VE of cycle (i-1) (NO
branch of procedural step (16)), control information for cycle (i)
and control or reserve information for cycle (i+1) are transmitted
according to procedural step (18). The injection process is
triggered with control information for cylinder (i) and reserve
information for cylinder (i+1) according to procedural step (21).
After that, the process returns to procedural step (14) while index
"i" is increased by the value 1.
[0045] The foregoing disclosure has been set forth merely to
illustrate the invention and is not intended to be limiting. Since
modifications of the disclosed embodiments incorporating the spirit
and substance of the invention may occur to persons skilled in the
art, the invention should be construed to include everything within
the scope of the appended claims and equivalents thereof.
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