DE2951051A1 - Spark ignition IC engine - has fuel mixture optimised for middle load with auxiliary engine coupled at upper middle or upper ranges - Google Patents

Abstract

The spark ignition engine (1) varies ignition timing with constant high air excess and constant charge when running in the lower middle load range. The charge is varied with constant high air excess and constant timing in the lower load range, whilst in the upper range the mixture is enriched with constant charge. The engine is designed to reach maximum output and minimum relative fuel consumption within this middle range, whilst in the upper or in the upper middle load range, an auxiliary engine (2) is coupled to the engine output. This auxiliary engine then runs near its full output with constant optimum timing.

Description

3180 Wolfsburg - 3 -

K 2851/1702-pt-hu-sa 1 8. ϋβΖ. 1979

Method and arrangement for operating an internal combustion engine with external ignition

(Addition to patent ... (Note P 28 24 472.6))

The invention relates to a method according to the preamble of claim 1. This method, which is protected in the main patent, offers the special The advantage that despite the setting of the three influencing variables air ratio, filling and ignition time (or ignition angle) from a single accelerator lever, in usually an accelerator pedal, the decoupling of the necessary to optimize the operation of the machine in its various operating modes mentioned three influencing variables is ensured. There are three working areas, which are also referred to as different braking load areas can be chosen so that apart from in the area of high braking load, as occurs when accelerating, especially in emergency situations, the operation of the machine with regard to low fuel consumption by setting a lean fuel-air mixture is optimized, and that only in the den the upper working range associated with high braking loads, the air ratio is changed with a view to achieving optimum performance.

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ORIGINAL INSPECTED

The invention is based on the object of the method or the arrangement the main patent for a further reduction in fuel consumption further training. The inventive solution to this problem is characterized by the method specified in claim 1; an advantageous arrangement to carry out this process is the subject of claim 2.

In the invention, therefore, with regard to the object to be driven, for example a motor vehicle, so "small" designed machine is used that it is already close at middle positions of the accelerator lever (accelerator pedal) the full load line is operated in the power-speed diagram, so that practically no power reserve is available for acceleration processes. The additional power required for this is provided by the auxiliary machine that is then activated, which in turn again with regard to the Fuel consumption can be optimized.

The connection of an auxiliary machine to a main machine in order to obtain additional power is known per se from DE-OS 26 10 098, F02D 25/00. Depending on the signals of a torque monitor arranged on the output shaft of the main machine, a clutch is closed between the flywheel of the main machine and the auxiliary machine and the ignition of the auxiliary machine is switched on so that it is started. This state of the art, however, lacks the combination of features of the main patent that is to be designated ^{as “selective influencing variable control 11”.}

Another possibility for increasing the efficiency is the subject of the claim 3.

An embodiment of an arrangement for implementing the invention The method is explained below with reference to the drawing. Show it:

Fig. 1 schematically shows the arrangement and

Figures 2 and 3 are diagrams explaining the operation of the arrangement.

The representation of the relationships in the selective control of influencing variables per se is waived, since it is the subject of the main patent there in detail is to describe.

The arrangement shown in the figures contains what can also be referred to as the main engine Otto internal combustion engine 1 as well as the one here also as an Otto engine

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Executed auxiliary machine 2. Both machines are via clutches 3 or 4 can be connected to a flywheel 5 or 6; Between the gearboxes and the flywheels a power transmission 7 consisting of gearwheels is arranged, which serves to increase the torque generated in the auxiliary machine 2 when the clutch 4 is engaged in addition to that of the machine 1 originating torque over the usual main clutch 8, the usual gear 9 and the differential 10 in this embodiment to direct drive wheels 11 of a vehicle to be driven by the machines.

The clutches 3 and 4 are hydraulically over in this embodiment Valves 12 and 13 are actuated, which in turn are controlled by the control device 14. At 15 a hydraulic accumulator is connected.

The control device 14 also contains the control device described in detail in the main patent for the selective control of influencing variables of the machine 1, which is indicated in the figure by the broken line 16. In this context, reference is made to the representation in the main patent.

The control device 14 are accordingly various operating parameters of Internal combustion engine supplied, as indicated by arrows 17. These include signals for the torque and the position of the accelerator lever, usually an accelerator pedal. The machine 1 is like this "small" designed that even in the middle working area of this machine, So at medium torques, an operation takes place in the vicinity of the full load line and thus with good efficiency. However, this has the consequence that, for example for acceleration processes, only a small amount, as a rule not sufficient power reserve is available. Therefore, already at the upper end of the middle working range of the machine 1, that is to say still in the area of the control or regulation of the same by changing the charge at a constant air ratio, the control device 14 engages the clutch the connection of the auxiliary machine 2, which in turn is adjusted to optimize consumption. But it is also possible to do this connection only in the upper working area of the machine 1, so already a certain enrichment

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of the fuel-air mixture supplied to this machine. These both possibilities are shown in the diagrams of FIGS. 2 and 3, in which the the same representation is selected as in Fig. 4 of the main patent:

In both diagrams, the normalized is above the normalized accelerator pedal travel s

^s max torque M. applied. The main engine has the three at the beginning

^M d max
defined working areas I, II and III, which are limited by the accelerator pedal positions A1 (idle position), B1, C1 and D1. Of the corresponding areas of the auxiliary machine, only the middle working area between the accelerator pedal positions B2 and C2 and the upper working area between C2 and D2 are of interest.

If one now looks at FIG. 2, the auxiliary machine is only switched on at the end of the upper work area III of the main machine, namely at the point D1, i.e. after the mixture supplied to the main engine has been enriched. With further When the accelerator pedal position s is increased, that work area of the auxiliary machine is first passed through which corresponds to area II of the Main engine through filling control with constant ignition point and air ratio is marked, and after the point C2 is exceeded, the further takes place Control of the arrangement by changing the air ratio also of the auxiliary machine.

In the case on which FIG. 3 is based, however, the activation takes place Auxiliary machine already at the end of work area II of the main machine, namely at the accelerator pedal position characterized by point C1. While of the work area III of the main engine, in which it is controlled by changing the mixture occurs, the auxiliary machine is already working accordingly, and there is an overlap of the third working area of the main machine with the middle working area of the auxiliary machine characterized by filling control and the upper working area characterized by mixing control the auxiliary machine.

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The control device 17 is also used to switch on the machines individually assigned loaders 18 and 19, which are formed here by compressors are. This charge is used to change the filling in the central working areas of machines 1 and 2.

The auxiliary machine will be optimized for higher speeds than the main machine and made to work at higher speeds; the difference between the The power transmission 7 bridges the speeds of the two machines with its Gear ratio.

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Claims (3)

VOLK SWA GEN WE R K SHARED COMPANY 3180 Wolfsburg K 2851/1702-pt-hu-sa ■ * "* ^ βΖ, 1979 Claims Method for operating an internal combustion engine with spark ignition of a fuel-air mixture, whereby in a lower working range of the machine with low braking loads including idling a regulation or control by ignition timing change with constant high air ratio and constant filling, which is equal to the filling at the lower end of a middle The working range takes place in which the regulation or control takes place by changing the charge at a constant high air ratio and constant ignition point, which is equal to the ignition point at the upper end of the lower working range, while the regulation or control is carried out in an upper working range with high braking loads Mixture change with constant filling and essentially maintaining the ignition point present in the middle working range takes place, according to patent ... (Note P 28 24 472.6), characterized in that the machine (1) is designed for such a small power that it is already in the middle work area ch (II) is operated near the line of minimum specific fuel consumption in the power-speed diagram ("full load ¹¹ ), and that in the upper working range (III) or at the upper end of the middle working range (II) of the machine one with also essentially Tristantem Auxiliary machine (2) operated close to full load is switched on at the optimum fuel-consumption ignition point. 1 30026/0196 Vortliicfider understanding! He, SchmUdcei, Vorsüiei.doi K «rl-H« lni Biieni ■ Prol. Dr. teöin. Crnsi F, she ■ Ijr) ut. Pel »t flor * 2. Arrangement for performing the method according to claim 1, characterized in that that on the auxiliary machine (2) on the output side in front of a Power transmission (7) a clutch (A) is arranged, which via a control device (1A) as a function of the position of an accelerator lever (Accelerator pedal) of the machine is operated. 3. Method for operating an internal combustion engine with spark ignition Fuel-air mixture, being in a lower working area of the machine with low braking loads including idling a control or Control by changing the ignition timing with a constant high air ratio and constant filling, which is equal to the filling at the lower end of a medium working range, takes place in which the control or Control by changing the charge with a constant high air ratio and constant ignition point, which is equal to the ignition point at the upper end of the The lower working range is carried out, while in an upper working range with high braking loads, the regulation or control is carried out by changing the mixture takes place with constant filling and essentially maintaining the ignition point in the middle operating range, according to patent ... (note P 28 24 472.6), in particular according to claim 1, characterized in that in the central working area (II) of the machine (1) and / or the auxiliary machine (2) the filling change is made using a loader (18,19) takes place. 130026/0196