SE1451164A1 - Method and apparatus for operating an internal combustion engine operating with alcohol and alcohol containing mixed fuels - Google Patents

Abstract

SUMMARY Method and apparatus for operating an alcohol and alcohol combustible combustion engine A process and apparatus for operating an alcohol and alcohol combustible combustion engine, the ignition of which is effected by a separate device, with at least one heating device for to heat the industry and a heat control device for controlling and / or regulating the heating power of the heating device. Upon fulfillment of a criterion indicative of an impending start of the internal combustion engine and upon fulfillment of a criterion from which a cold start of the internal combustion engine can be concluded, the thermal control device is activated. Depending on the inhalation or non-inhalation of a tooth and starter device for the internal combustion engine, different temperature drilling values (T_SP_LOW, T_SP_HIGH, T_SP_ST) are installed for the industry by means of the heat control device. The temperature setpoint (T_SP_HIGH) at ignition and no other starting device has the internal combustion engine is then selected higher than the temperature value (T_SP_LOW) at ignition. The temperature drilling value (T_SP_ST) at the ignition and any other starting device is selected higher than the temperature drilling value (T_SP_HIGH) at the ignition and non-any starting device.

Description

TECHNICAL FIELD The invention relates to a method and apparatus for operating an alcohol and alcohol-containing internal combustion engine, the ignition of which is provided by a separate device, with a heating device for heating the industry and a heat control device for controlling and / or regulating the heating power of said heating device.

BACKGROUND Vehicles are vehicles that can be operated optionally with alcohol or with alcohol containing mixed fuels, ie. with the industry with variable alcohol content, as with Ottobranslen (petrol), ie. the industry for Otto engines. Alcohols, e.g. ethanol or methanol in the industry can then be present in different proportions in the range between 0 and 100%. The SAdana industry is also referred to as "Flex Fuel" or "Flexible Fuel" (FF) and the thus drivable motor vehicles as Flexible Fuel Vehicle (FFV). Common alcohol mixtures are, for example, M85, ie. 85% methanol in the industry, and E85, ie. 85% ethanol in the industry, in which the petrol content of foliage in bAcla cases is 15%. In the Brazilian market in particular, motor vehicles were used, in which pure ethanol (E100) was used as a fuel.

The use of the Adana mixed fuel with a high alcohol content has the disadvantage that the vehicle can only be started at low temperatures, since alcohol evaporates very poorly at low temperatures. For vehicles that are refueled with 100% ethanol, for example, a start below + 12 ° C (flash point ethanol) is almost impossible. Since cold start problems thus occur without special measures, small, fixed built-in fuel additive tanks are carried in vehicles that allow operation with very high alcohol concentrations, which fuel additive tanks contain a small amount of starting fuel, e.g. Brazilian gasoline ("Gasohol", E20 fuel). To start the vehicle under certain external temperatures, petrol was then used as starting fuel or injected in addition to the alcohol so that a combustible mixture was formed. The problem here, however, is that at all times only a very large amount of fuel is taken out of the add-on container containing the starting fuel at a cold start, and over time this starting fuel becomes all the more common. By "samre" in this context is meant that the slightly volatile hydrocarbon moieties such as propane and butane are evaporated and lacquered out of the addition tank due to the high temperatures in the engine compartment during the internal combustion engine and thus the vehicle operation, and by the high temperatures during the summer months, during which no starting fuel is needed. The constituents necessary for a cold start are then lost or at least greatly reduced. Under certain circumstances, a cold start can no longer be performed since then.

U.S. Pat. Nos. 4,911,116 A and 4,646,691 A disclose internal combustion engine fuel systems for a motor vehicle which are operated with alcohol and have separate cold start tanks containing gasoline which are used to start the engine. Then, when the engine has started and starts to get hot, the main tank is connected to the alcohol-containing fuel instead of the cold-start fuel. It is disadvantageous that both tanks require a separate filling, ie. supply lines to the body exterior and any separate tank hatches must be provided. The driver must also have 160 fuel levels in both tanks in order to be able to fill them in time. Furthermore, the product must distinguish between two separate tank filling tubes, which in the event of negligence can lead to an incorrect filling of the filled tanks.

DE-OS 25 36 432 discloses an internal combustion engine which can be driven with alcohol and alcohol containing the mixed fuels and in which a cold start device with an electrically driven heating device is provided in a side suction duct which surrounds a main mixture forming device. The necessary air for the cold start mixture is taken from the main air suction duct, whereby the flow connection can be interrupted by a shut-off device. By heating the fuel-air mixture, the starting probability (Startfreudigkeit) of the internal combustion engine at low ambient temperatures is improved.

In addition to this Jr already cold start system kanda for with high alcohol content in the industry drivable motor vehicles that heat the industry to higher temperatures by means of electrical energy from the electric vehicle system (the bat). The fuel heating in the injector or in the spreader bridge can then take place by means of a resistive or inductive heating principle. From JP-A-52 665/1982 a heating device is known for heating an inlet line, the heating device being controlled depending on the output signal of an alcohol concentration sensor and in which the amount of heat production has the heating device becomes larger when the alcohol concentration takes a reference value or is larger.

All these electric heating systems have the disadvantage that they need a certain heating time which depends in particular on the coolant temperature of the motor vehicle before the starting procedure of the internal combustion engine and that not much power for the heating systems can be taken out of the electric vehicle system.

This preheating resp. heating time, the electric heating systems have emerged as a loss of comfort that can not be left Lido compared to cold start systems with an additional tank for a starting fuel.

SUMMARY OF THE INVENTION The object of the invention is to show a process and a device for operating an internal combustion engine operating with alcohol or with alcohol-containing mixed fuels, which process resp. which device provides a fast start of the internal combustion engine even at low temperatures and very high alcohol content in the industry and thereby does not overload the electric vehicle system.

This task is solved according to the features of the independent claims. Advantageous further developments and embodiments of the invention are characterized in the subclaims.

The invention is characterized by a method and a corresponding device for operating an alcohol and alcohol-containing mixed combustion engine, the ignition of which is effected by a separate device, with at least one heating device for heating the fuel and a thermal control device for controlling and / or regulating the heating power of said at least one heating device. Upon fulfillment of a criterion indicative of an impending start of the internal combustion engine and upon fulfillment of a criterion from which it is possible to conclude a cold start of the internal combustion engine, the thermal control device is activated. Depending on the use or non-use of a tooth and 4 starter device for the internal combustion engine, different temperature drilling values are installed for the fuel by means of the heat control device. The temperature drilling value when the ignition is switched on and the unused starting device of the internal combustion engine is chosen higher than the temperature value when the ignition is switched off. The temperature drilling value for newly applied ignition and used starting device is selected higher than the temperature drilling value for suitable ignition and unused starting device.

With the method according to the invention, it is on the one hand possible to clearly reduce the time for heating the fuel and thus the waiting time for the motor vehicle driver until it can safely start the internal combustion engine, which increases comfort in comparison with known heating systems with constant heating power.

Upon the occurrence of certain trades which indicate an imminent cold start of the internal combustion engine, the fuel is heated up to a first, relatively low temperature drilling value. This first temperature drilling value is chosen in such a way that no blistering occurs in the industry. A typical value is 60 ° C. Should arida no start of the internal combustion engine take place within a first predetermined period, e.g. since the driver has admittedly opened the car door, but has not switched on the ignition, the heating device is deactivated again, ie. stanges ay.

By selecting a lower first temperature drilling value at a first time, at which a start of the internal combustion engine is probable, but where it is not yet certain that it will be carried out, an excessive load on the electric vehicle system can be avoided.

If such preheating is switched on to the first, lower temperature drilling of the ignition during the first period, then it is a stronger indication that a start of the internal combustion engine could take place immediately. Therefore, the industry is heated to a second temperature drilling value, which is higher than the first temperature drilling value, for example to a value of 100 ° C.

Occurs during a second pre-determined period since ignition "PA" no start of the internal combustion engine, ie. the starting device is not activated, since the Ware e.g. has only switched on the ignition to listen to music by means of the car radio, so is regulated to the first, lower temperature drilling value and after the end of the first period the heating device is deactivated, ie. stanges ay. It also helps5 to reduce the load on the electric vehicle system.

Since after switching on the ignition in this case a heating only needs to take place from the first temperature drilling value to the second temperature drilling value, s5 results in a total smaller heat effect as in a shortened heating time compared with a heating from a lower starting temperature up to the second the temperature drilling value.

If the starting device is also used within the first period, then the industry is heated up to a third temperature drilling value, which is higher than the second temperature drilling value, for example to 120 ° C, whereby a quick start of the internal combustion engine is ensured even at 15 ambient temperatures. In this case, the heating only needs to take place from the second temperature drilling value to the third temperature drilling value, so that only a small heating effect still needs to be supplied. This results in a shortened heating time in comparison with a heating output & a lower starting temperature up to the third temperature drilling value.

According to an advantageous design, in the case of a stationary internal combustion engine, switched on ignition and unused starting device, it is checked how often the ignition was struck p5 without the starting device being used in between. When a predetermined threshold value is exceeded for this number, a temperature drill value is selected which corresponds to the temperature drill value at the ignition ignition, since in this case it is not clear whether the Ware wants to start the internal combustion engine at all. Such an approach also contributes to the reduction of the heating effect and thus to a lesser load on the electric vehicle system.

According to a further advantageous design, during a post-start phase after a successful start of the internal combustion engine, the temperature drilling value is reduced with increasing time starting from the temperature drilling value when the ignition is switched on and the starting device is used. This reduction in temperature drilling value correlates with the increasing combustion chamber temperature and helps to relieve the electric vehicle system.

A further relief of the electric vehicle system becomes a result when the thermal control device is deactivated completely after the expiration of a period after a successful start of the internal combustion engine. This period is advantageously determined depending on the temperature of the refrigerant at the start of the internal combustion engine, on the alcohol content of the fuel and on the air / fuel ratio. This ensures on the one hand that the internal combustion engine does not die again after the start, and on the other hand that the heating only takes place as long as absolutely necessary.

According to a further advantageous design, the temperature drilling values for the fuel are determined depending on the temperature of the coolant at the start of the internal combustion engine and an air / fuel ratio, whereby an optimal heating effect under these boundary conditions is obtained.

According to the invention, the activation of the heating device and the selection of the heating effect are connected to transactions which, in terms of time, are before the start of the internal combustion engine.

According to a further advantageous design, the criterion for a possible impending start of the internal combustion engine is the touching or use of the door handle of the front door of the vehicle driven by the internal combustion engine, the signal of a switch arranged at the front door or of a door opening contact. Since already other functions, such as the activation of the lighting in the interior, are triggered in modern motor vehicles by touching or using the door handle or by opening the front door, there is a simple and cost-effective variant for activating the heating device in the past to results.

According to a further advantageous design, the signal of a sensor device is used as a criterion for a possible impending start of the internal combustion engine, in order to identify the seat coating of the front seat of the vehicle driven by the internal combustion engine. D5 5N / en this signal spirit is present in modern motor vehicles phase a cost-effective solution to activate the heating device in the past to results.

If the vehicle is secured by an active or passive access system against the unauthorized access, then the signal of a so-called mobile identification sensor can be analyzed, in the simplest case the transmitter of a radio-controlled remote control for central setting. Also, no additional components are necessary. DESCRIPTION OF THE DRAWINGS An exemplary embodiment of the invention is explained in the following with the aid of drawings. It shows: Fig. 1 in the form of a block diagram an internal combustion engine with petrol, alcohol or with optional mixing ratios of these industries with associated control device, Fig. 2 a flow chart of a program for controlling the fuel system for such an internal combustion engine. DESCRIPTION OF EMBODIMENTS Figure 1 shows in schematic representation a saliva with petrol, alcohol, which also with optional mixing ratios of these industries can be driven by an internal combustion engine 10 of a motor vehicle. Such motor vehicles are referred to as flexible fuel vehicles (FFV) or as variable fuel vehicles (VFV).

When the term fuel is used in the following, it means a fuel which either consists of pure petrol (Ottobransle), or of a mixture of optional proportions of petrol and alcohol or of pure alcohol, in particular pure ethanol (E100).

In Figure 1, only those components are shown which are necessary for the understanding of the invention. In particular, the toothed device suitable for the ignition of the fuel air mixture is omitted. The invention is explained with the aid of an internal combustion engine with four cylinders Z1-Z4; however, it is also irreplaceable for internal combustion engines with a different number of cylinders and, more specifically, independent of the nature of the engine concept, e.g. four-stroke Otto engine, two-stroke engine or rotary piston engine.

An intake manifold 11 and an exhaust manifold 12 are associated with the internal combustion engine 10, which by means of non-manufactured intake and exhaust valves communicate with the combustion chambers of the cylinders Z1-Z4 of the internal combustion engine 10. The feed air motor 10 The exhaust gases formed as a result of the combustion of the fuel / air mixture 8 are purified in an unmanufactured exhaust aftertreatment device and reach the surroundings via a non-manufactured muffler.

For starting the internal combustion engine 10, a starting device is provided which comprises, for example, an electric starting device 46 and a tooth starting contact 31.

The internal combustion engine 10 has a fuel supply system which includes a fuel storage tank 13 and an electrically driven 15 pressure fuel pump 14 which connects fuel from the fuel storage tank 13 via a low pressure fuel line 15 to a spreader bridge for the cylinder 19. 10, with the aid of which the fuel injectors 19 helped the fuel to be injected directly into the combustion chambers of the cylinders Z1 to Z4 and which are in fluid communication with the spreading bridge 18 via lines not further designated.

Since the operating ratio of the internal combustion engine 10 also depends to a large extent on the nature and composition of the fuel, an alcohol concentration sensor 26 is provided in the fuel pollution system, which alcohol concentration sensor 26 detects the proportion of alcohol in the fuel. the alcohol concentration in the fuel is also determined by means of a model formation from operating parameters of the internal combustion engine 10, i.e. from already existing food quantities, for example by taking into account the signal of an exhaust sensor 28 arranged in the exhaust path 12 of the internal combustion engine 10, as described in US 6,257,17 .

In order to ensure a start of the internal combustion engine 10 even at low temperatures during operation with a high alcohol content fuel, an electric heating system for the fuel is provided, which is described in more detail below.

Each of the individual fuel injectors 19 is provided with an electric heater and a temperature sensor 21 which registers the temperature of the fuel in each fuel injector 19. It is also possible to provide only a single temperature sensor 21 at one of the fuel injectors 19, the food value of which is representative of the industry temperature. in all industry injectors 19. Alternatively, the temperature can be determined via a change in the material properties of the industry injectors. Alternatively or further in addition to the heating of the fuel injectors 19, an electric heating device 22 is arranged in or at the spreading bridge 18. The heating system consists exclusively of the heating device 22 at the spreading bridge 18, so in the case of a temperature sensor 23 serving to register the industry temperature. For control and / or control of the described heating system, a heat control device 30 is provided, by means of which the heating effects can be varied for the heating devices 20, 22, so that different industry temperature drilling rigs are installed. For this purpose, the signals of the temperature sensors 21, 23 for the industry, the signal of a coolant temperature sensor 25 and the signal of the alcohol concentration sensor 26 are evaluated by the heat control device 30, as will be explained in more detail with the aid of Figure 2.

Heat control device 30 includes a computing unit 36 which is connected to a program memory 37 and a cache memory 38 (data memory). The calculation unit 36, the program memory 37 and the cache memory 38 may each comprise one or more microelectronic building elements.

Alternatively, these components may be partially or completely integrated in a single microelectronic component. In program memory 37 resp. the memory 38 is a program resp. In particular, a procedure for heating the fuel is implemented, which is processed by the calculator 36 before and during the operation of the internal combustion engine 10, as will be explained in more detail with the aid of Figure 2. In the memory 37 are, among other things, different drill guards T_SP_LOW, T_SP_HIGH. T_SP_ST for the industry temperature in the industry injectors 19 resp. in the spreader bridge 18 and different threshold values t_TEMP_SP_LOW, t_SP_LOW_SW, t_SP_HIGH_SW for periods saved. Furthermore, in the heat control device 30, two timers 39A, 39B are present, the function of which will also be explained in more detail with the aid of the description of the process according to Figure 2.

The heat control device 30 is connected to the tooth starting contact 31, which in position I releases the ignition of the internal combustion engine 10 and in position II activates a starting device for starting the internal combustion engine 10, for example an electric starter.

The reference numeral 32 denotes an electrical switch element, the actuation of which is interpreted as an indication of a possible imminent starting procedure of the internal combustion engine 10. This may be the signal of a switch arranged at the door of the front door or a door opening contact which also activates the interior lighting. If the vehicle is equipped with a sensor device to identify the seat coating, then the signal of this sensor can also be used.

If the vehicle has a so-called keyless, active or passive access system, then the signal of a mobile identification sensor, which serves to open and close and / or open doors of the motor vehicle driven by the internal combustion engine 10, can be used. In the simplest case, the use of the transmitter by a radio-controlled remote control for central installation of the doors and luggage compartment can be interpreted as an indication of a possible imminent starting procedure of the internal combustion engine 10. In Figure 1, such a transmitter is marked with reference numeral 33 and the associated receiver with vehicle designation. 34.

The said devices 32, 34 make it possible to already activate the heating devices 20, 22 before the driver of the motor vehicle uses the tooth-start switch 31 resp. a start-stop button.

Furthermore, the thermal control device 30 connected to a voltage head 35, preferably with the vehicle battery has the electric vehicle system. It supplies, among other things, via non-produced power output stages the electrical energy for the heating devices 20, 22.

For controlling and regulating the internal combustion engine 10, an electronic control unit (ECU) 24 is provided, all electrically connected to the thermal control device 30, preferably by means of a CAN bus 40. Thereby, input signals from sensors directly supplied to the thermal control device 30 can also be transmitted to the motor control device 24 for further processing. Likewise, input signals from sensors directly supplied to the motor control device 24 can also be transmitted to the heat control device 30 for further processing. In addition, operating quantities and / or calculated quantities can be exchanged via this CAN bus 40.

Additional sensors are associated with the motor control device 24, which sensors register different food quantities and determine the respective food value to the food quantity. Operating quantities include, in addition to food quantities, also derived quantities. The motor control device 24 determines control quantities depending on at least one of the feed quantities and / or the operating quantities, which control quantities are then converted into one or more control signals for controlling actuators by means of corresponding stables. The sensors are, for example, the temperature sensor 25 for the coolant temperature TKW, a crankshaft angle sensor 27 which registers a crankshaft angle, vilkent which is then assigned a speed N, an alcohol concentration sensor 26 and the exhaust sensor 28 in the exhaust section 12 and further for the operation of the internal combustion engine 10 signals are generally indicated by the male reference ES.

The actuators are, for example, a throttle 29 in the intake section 11, the fuel injectors 19 and the low pressure fuel pump 14. Additional signals for further actuators which are necessary for the operation of the internal combustion engine 10, but which are not explicitly shown, are generally denoted by the reference numeral AS.

The motor control device 24 comprises on the edge a calculating unit 41 which is connected to a program memory 42 and a cache memory 43 (data memory).

Among other things, the engine control device 24, depending on a load signal and the speed N, determines, while evaluating the signal of the alcohol concentration sensor 26 for the composition of the fuel, the appropriate timing and injection period.

Program resp. the values are stored in the program memory 42 resp. the cache 42, which programs resp. The values are necessary for the operation of the internal combustion engine 10. Among other things, quantities of characteristic curves ("Kennfelder") KF1, KF2 and various threshold values, the significance of which will be explained in more detail with the aid of Figure 2, are stored in the memory 43.

Figure 2 shows in the form of a flow chart a method for controlling a cold start system within an industry supply system having an internal combustion engine.

The process begins when at least one criterion is met which is indicative of an impending start of the internal combustion engine 10 (step 51). The touching or inhaling of the driver's door handle by a person may, for example, anyandas as a criterion or sign allowing a start of the internal combustion engine 10 to be probable. Also by evaluating the signal of a switch arranged at the front door of the driver's door or of a door opening contact, which for example activates the interior lighting of the passenger compartment, can be interpreted as an indication of a possibly imminent start of the internal combustion engine. If the vehicle is equipped with a sensor device for identifying the seat coating, then a signal generated by this sensor device can also be interpreted as an indication of a possibly imminent start of the internal combustion engine 10.

If the vehicle driven by the internal combustion engine 10 has a so-called keyless access system, then the activation of the transmitter by a radio-controlled remote control for opening and closing and / or loading the vehicle doors can be used as an indication of a possible imminent starting procedure of the internal combustion engine 10. a radio-controlled remote control for opening a gate has a garage, in which the vehicle is parked or in front of which the vehicle is parked, can be interpreted as an indication of an imminent start has the internal combustion engine 10.

Are none of these mentioned criteria resp. the signs are fulfilled, then the processing is continued anyo in step Si, possibly after the expiration of a predetermined waiting period t_WAIT.

However, if there is an indication in step Si which could indicate an imminent start of the internal combustion engine 10, then the engine control device (ECU) 24 is activated and it is read whether it is necessary to install the cold start system for heating the fuel (step S2).

Such a cold start system is required in particular when the industry has a high alcohol content, since alcohol evaporates very poorly at low temperatures and thus defends or even makes a cold start of the internal combustion engine 10 impossible.

In detail, in step S2, the temperature has been used, the coolant TKW, the alcohol content ALC_AN in the industry and a time period t_ST after starting the internal combustion engine 10 for deciding whether the cold start system is needed.

If the temperature has the coolant TKW, which as a very good approximation reflects the temperature has the internal combustion engine 10, below a predetermined threshold value TKW_SW, then the cold start system must be activated. Since the temperature at which a cold start of the internal combustion engine 10 can still be carried out depends on the alcohol content ALC_AN in the industry, this threshold value TKW_SW depends on the alcohol content ALC_AN stored in a plurality of characteristic curves KF1 in the cache 43 has the engine control device 24. The higher the alcohol content ALC AN in the industry is, the more the threshold value TKW SW, Iran and with which the cold start system must be activated, differs to the higher temperature value. 13 The value for the temperature of the refrigerant TKW is obtained from the signal of the temperature sensor 25, the value for the alcohol content ALC AN is obtained from the signal of the alcohol concentration sensor 26. From these! Pada values, the threshold value TKW_SW is determined empirically and is saved in the set of characteristic curves KF1.

Furthermore, in step S2, it is checked whether a predetermined period t_ST has elapsed since the start of the internal combustion engine 10. In addition, rake staging is read by a duck present in the engine control device 24 and also for other control and / or control purposes serving time-after-start racks 44. so that the determined period t_ST is greater than a predetermined threshold value t_ST_SW, s5 it is assumed that the starting procedure of the internal combustion engine 10 is successfully completed and that the internal combustion engine 10 runs stably.

The cold start system is not needed resp. is no longer required and can thus be deactivated (step S3) and the procedure is completed (step S20).

The threshold value t_ST_SW is determined empirically depending on the coolant temperature TKW and the alcohol content ALC AN and is stored in a plurality of characteristic curves KF2 within the memory memory 43 of the motor control device 24. This means that, for a certain coolant temperature TKW and a certain alcohol content ALC_AN in the industry, one needs corresponding period within which the cold start device must be activated.

If the result of the unloading in step S2 is that a heating of the fuel is necessary for a proper start of the internal combustion engine 10, then the heat control device 30 is activated in a step S4. This is preferably done via the CAN bus 40.

In a subsequent step S5 it is checked whether the internal combustion engine 10 is running, that is to say whether its speed is above a predetermined value (logic variable LV_ERU = 1). At the first review of the procedure, s5 is not the case and the procedure continues with a step S6.

In step S6, it is read whether the ignition of the internal combustion engine 10 is fitted. In a conventional tooth-start switch 31 activated by a key, the position (position I, figure 1) of the tooth key (logical variable LV_IGK = 1) is also evaluated.

If the ignition is not fitted (position 0, figure 1) s5, the procedure continues with a step S7. It is read whether a predetermined period t_SP_LOW determined by the timer 39A has expired, that is to say it is greater than a predetermined threshold value t_SP_LOW_SW. At the first 14 steps of the procedure, the razor position of the razor 39A is still zero, i.e. it is not started and the procedure continues with a step S8.

In step S8, a first drilling value T_SP_LOW is determined for the temperature to which the brat ice is to be heated. This drilling value T_SP_LOW is dependent on the temperature of the coolant TKW at the start of the internal combustion engine 10 and on air-fuel ratio AFR stored in a plurality of characteristic curves of the cache 38 of the thermal control device 30. By means of signals of the thermal control device 30 the heating devices 20 and the fuel injector at the spreader bridge 18, so that the determined first temperature drilling value t_SP_LOW, for example 60 ° C, is reached.

The temperature of the away temperature is monitored with the aid of the temperature sensors 21 at the fuel injectors 19 resp. of the temperature sensor 23 at the spreading bridge 18 and thereby enables a control of the heating power of the heating devices 20, 22.

In a subsequent step S9, the rudder assembly is raised to the timer 39A and the process continues with step 52. If the cold start system is still necessary, the engine is still not running and the ignition is still turned off, steps S2, S4 to S9 are continued until it is determined for the first time. that the predetermined period t_SP_LOW, for example 30 seconds, has expired. In this case, branch S10 is branched off, in which the power supplies of the heating devices 20 resp. 22 suspended.

The above-described review of the process reflects the case that although an indication of a possible start of the internal combustion engine 10 has occurred, however, within the predetermined period t - SP _LOW since no starting attempt has been made. This can happen, for example, when a person has opened the vehicle's done, but not used the tooth key, because it just wanted to retrieve something from the vehicle or put something in it. In this case, the heating is no longer needed.

However, during the description described in step 6, the result is that the ignition is switched on (stall 1 has a tooth-starting contact 31, figure 1), ie. the logic variable LV_IGK = 1, s5 dr this a further, compared with criteria in step Si stronger indication p5 that a possible start of the internal combustion engine 10 immediately forest5r. In a subsequent step S11, it is read whether the tooth wrench had already been placed in position I one Ong earlier (logical variable = 1). If this is the case (yes), s5 is read in a subsequent step S13 whether the number of tooth key uses (stall 0 to stall 1) has exceeded a predetermined threshold value CTR_IGK_ON_SW. If the reading is positive, the procedure continues with step S7. The threshold value CTR_IGK_ON_SW can for instance be between 3 and 5 and Jr stored in the value memory 43 of the motor control device 24.

If the reading in step S11 results in a negative result (no), then in a step S12 the razor position CTR_IGK_ON of the razor 45 is increased and the procedure continues the same as with step S13.

The basis for the readings in steps S11 and S13 is the idea that there is no serious intention to start the internal combustion engine in the case of multiple use of the tooth wrench in position I and subsequent failure to use in position II. The use of the tooth wrench, for example, was only intended to sI5 p5 the radio or the like. In this case, then the activation of the heating device 20, 22 takes place with a heating effect which has a relative 15g temperature, for example the specified 60 ° C to MO, or when the predetermined period is exceeded the complete deactivation of the heating device.

However, it was identified in step 513 that the tooth key was either used for the first time or a repeated number of times, but this number has not yet reached the threshold value CTR_IGK_ON_SW, so in the next step S14 it is read whether a non-predetermined period t_SP_HIGH, ie determined by the timer 39B Jr greater than a predetermined threshold value t_SP_HIGH_SW. The timer 39B starts to start when it is determined in step S6 that the ignition is turned on p5. If the threshold value T_ SP _LOW is not yet reached, then a second, in comparison with the first drill value T_SP_LOW, increases the drill value T_SP_HIGH for the temperature to which the industry is to be heated (step S15). Also, T_SP_HIGH Jr. was dependent on the temperature of the refrigerant TKW at the start of the internal combustion engine 10 and on the air-fuel ratio AFR stored in a plurality of characteristic curves of the cache 38 of the heat control device 30. The heating devices 20 of the fuel injectors 19 and / or the heating device 22 have is activated by means of signals by the heat control device 30, so that the determined second temperature value T_SP_HIGH, for example 100 ° C, is reached.

The maintenance of this elevated away temperature is also monitored with the aid of the temperature sensor 21 at the fuel injectors 19 resp. of the temperature sensor 23 at the spreading bridge 18 and thus a regulation of the heating effect is made possible. In a subsequent step S16, the rake stand of the timer 39B is raised and the process continues with step S2.

The determination of a drilling value T_SP_LOW for the temperature drilled in comparison with the first drilling value T_SP_LOW is then justified in that a starting procedure of the internal combustion engine 10 is at passable ignition (logic variable LV_IGK = 1) soon more probable than at rejected ignition. In case it really comes to starting the internal combustion engine 10, then the industry is then optimally heated and the starting procedure of the internal combustion engine 10 is successful even at the low temperature.

But even with only one Ong pAslagen and pAslagen remaining ignition, it may happen that the tooth start switch 31 is not maneuvered to position ll within the predetermined period t_SP_HIGH (unloading in step S14), i.e. no start of the internal combustion engine 10 is initiated. After an unsuccessful expiration of the period t_SP_HIGH, for example 20 seconds, the procedure continues with step S7 which has already been explained.

Thereby a lowering of the higher temperature drilling value T_SP_HIGH takes place to the stored temperature drilling value T_SP_LOW, which is equivalent to a lowering of the heating effect.

It is determined during a repeated review in step 5 that the internal combustion engine 10 is started (LV_ERU = 1), s5 is read in a step S17 whether the internal combustion engine 10 is still in the start phase or in the post-start phase. The internal combustion engine 10 is in the post-start phase when the speed has exceeded a predetermined threshold value, for example 1000 min-1 (logic variable LV_ST_END = 1), otherwise in the start phase.

If the internal combustion engine 10 is still in the starting phase, at which the starting device 46 is still activated, for example an electric starter which is still engaged with the flywheel of the internal combustion engine 10, then the procedure continues with a step S18. In this step S18, a third, in relation to the first drilling value T_SP_LOW and the second drilling value T_SP_HIGH, an Ong to increased drilling value T_SP_ST is determined for the temperature to which the industry is to be heated.

Also this borvarde T _ SP _ST al. depending on the temperature of the refrigerant TKW at the start of the internal combustion engine 10 and the air-fuel ratio AFR stored in a plurality of characteristic curves of the cache 38 of the thermal control device 30. By means of 17 signals of the thermal control device 30 the heating devices 20 of the fuel injectors 19 and / or the heating device 22 are activated. , s5 that the existing third temperature drilling value T_SP_ST, for example 120 ° C, is reached.

If the unloading in step S17 results in the internal combustion engine 10 being in the post-start phase, i.e. a successful start of the internal combustion engine 10 is completed due to the heating of the fuel, the heating devices 20, 22 are not immediately deactivated, but during the post-start phase of the internal combustion engine T from the set of characteristic curves for the drill value T_SP_ST, by weighting this set of characteristic curves depending on the period after the start t_ST (step S19). With increasing time, the heating effect is reduced and thus the temperature in the industry. The longer the internal combustion engine 10 is running, the less the industry needs to be heated to ensure proper operation of the internal combustion engine 10.

It is determined after step S2 that the period t_ST has elapsed, for example 60 seconds have elapsed, sA heating of the industry is no longer necessary, the heating devices 20, 22 in step S3 are switched off, the heating device deactivated and the process ends with step S20.

The invention was explained with the aid of an example in which the motor control device 24 and the heat control device 30 Jr are manufactured as separate components. However, it is also possible to fully integrate the heating control device 30 with the associated output stages of the heating devices 20, 22 in the motor control device 24 or to integrate only the control electronics and to externally arrange the output stages of the heating devices 20, 22. In the described embodiment the motor vehicle has a conventional tooth three stalls (0-1-11) and for the control / regulation of the heating effect these contact stalls are read. However, the invention is equally applicable to modern motor vehicles, in which no key in the actual Bernark archive needs to be put in a lock to activate the ignition and start the engine. In such keyless-start or keyless-go systems, the presence of the "electronic key", also often referred to as a mobile identification sensor, racks in the interior, the start-up procedure then racking by pressing a start-stop button. In this case, the signals of these components are analyzed to activate the heating device early. 18 When referring to an internal combustion engine, the ignition of which is effected by a special device, this means and throughout the document what is summed up in German with the single word "fremdgezundet". In one example, it is an internal combustion engine that does not operate according to the actual ignition principle. 19 conceptually / HANvIsNINGSBETECKNINGSLISTA combustion engine 11insugningsstracka 12avgasstracka 13bransleforradsbehallare 14lagtrycksbranslepump lagtrycksbransleledning 18spridarbrygga 19bransleinjektor hot device injectors 21temperatursensor injector 22varmeanordning Fuel rail 23temperatursensor Fuel rail 24motorstyrningsanordning (ECU Electronic Control Unit) temperature sensor coolant 26alkoholkoncentrationssensor 27vevaxelvinkelsensor 28avgassensor 29strypspjall warm control device (HCU, heater control unit) 31tand start contact 32elektriskt switching 33sandare of radio-controlled remote control, mobile identification sensor 34 receiver of radio-controlled remote control voltage head, vehicle battery 36computing unit HCU 37 program memory HCU 38compartment memory, data memory HCU 39Atem tracker for heating when ignition for anyandandet of ignition 46startanordning of the internal combustion engine Nvarvtal TKWkylmedelstemperatur TKW_SWtroskelvarde coolant temperature T KSTternperatur fuel T_SP_LOWforsta Setpoint QST temperature T_SP_HIGHandra Setpoint QST temperature T SP STtredje Setpoint QST temperature T_SP_ASTborvarde for bransletemperatur in after the starting phase ESingangssignaler ASutgangssignaler, control signals Z1 Z4cylinder of the internal combustion engine AFRluft -branslefRelating KF1mantry of characteristic curves KF2mantry of characteristic curves t_WAITwant period t_STperiod after start of the internal combustion engine t_ST_SWthresolution value for period after start of the internal combustion engine t_SP_LOWperiod ALC_ANAlcohol content in the industry LV_ERUlogical variable engine running 21 LV_IGKlogical variable ignition LV_ST_ENDlogical variable engine operation outside start 22

Claims (13)

PATENT REQUIREMENTS A method of operating an alcohol and alcohol-containing mixed fuel combustion engine (10), the ignition of which is effected by a separate device, with at least one heating device (20, 22) for heating the fuel and a heat control device (30) for controlling and / or regulating the heat output of said at least one heating device (20, 22), characterized in that upon fulfillment of a criterion indicative of an impending start of the internal combustion engine (10) and upon fulfillment of a criterion from which it appears to end a cold start of the internal combustion engine (10), the heat control device (30) is activated, different temperature drilling values (T_SP_LOW, T_SP_HIGH, T_SP_ST) for the industry are installed by means of the heat control device (30) depending on any use or non-use of a tooth and start device (31, 46) the internal combustion engine (10), the temperature drilling value (T_SP_HIGH) in the event of ignition and an unused starting device (31, 46) of the internal combustion The motor (10) is selected higher than the temperature value (T_SP_LOW) at the ignition switch off, the temperature drill value (T_SP_ST) at the ignition ignition and use starting device (31, 46) is selected higher than the temperature drilling value (T_SP_HIGH) at the ignition switch and non-any start device 46). Method according to claim 1, characterized in that it is checked with a stationary internal combustion engine (10), when the ignition is switched on and the unused starting device (31, 46) how often the ignition is switched on without the starting device (31, 46) in between and that, when exceeding a predetermined threshold value (CTR_IGK_ON_SW) for this number, a temperature drill value is selected which corresponds to the temperature drill value (T_SP_LOW) in the event of ignition. A method according to claim 1 or 2, characterized in that it is checked at standstill internal combustion engine (10), at ignition on and unused starter (31, 46) whether a predetermined period (t_SP_HIGH) has elapsed since the first ignition of ignition and in the positive case, a 23 temperature drill value is selected which corresponds to the temperature drill value (T_SP_LOW) when ignition is switched off. A method according to any one of claims 1 to 3, characterized in that the heat control device (30) is deactivated in the event of rejected ignition after the expiration of a predetermined period (t_SP_LOW). Method according to claim 1, characterized in that the temperature drilling temperature during a post-start phase after a successful start of the internal combustion engine (10) is reduced by increasing time starting from the temperature drilling rig (T_SP_ST) when the ignition is applied and using the starting device (31, 46). Method according to one of the preceding claims, characterized in that the heat control device (30) is deactivated after the expiration of a period (t_ST) after a successful start of the combustion engine (10). Method according to claim 6, characterized in that the period (t_ST) is determined depending on the temperature (TKW) of a coolant at the start of the internal combustion engine (10), an alcohol content (ALC_AN) in the industry and an air / industry ratio (AFR). A method according to any one of the preceding claims, characterized in that the temperature drilling values (T_SP_LOW, T_SP_HIGH, T_SP_ST) for the fuel are determined depending on the temperature (TKW) of a coolant at the start of the internal combustion engine (10) and an air / fuel ratio (AFR). Method according to one of the preceding claims, characterized in that the touching or use of the door handle of the front door has the vehicle driven by the internal combustion engine (10) used as a criterion for an impending start of the internal combustion engine (10). Method according to one of Claims 1 to 8, characterized in that the signal of a driver 's door at the door load has the switch arranged by the vehicle driven by the internal combustion engine (10) or is used by a door opening contact as a criterion for an impending start of the internal combustion engine (10). Method according to any one of claims 1-8, characterized in that the signal of a sensor device for identifying the sate coating has been applied to the vehicle driven by the internal combustion engine (10) is used as a criterion for an impending start of the internal combustion engine (10). 24 A method according to any one of claims 1-8, characterized in that the signal of a mobile identification sensor (33), which serves for the opening and closing and / or sending of doors of the vehicle driven by the internal combustion engine (10), is used as a criterion for a impending start of the internal combustion engine (10). Apparatus for operating a fuel system of an alcohol or alcohol mixture fueled combustion engine (10), the ignition of which is effected by a separate device, with at least one heating device (20, 22) for heating the fuel and a heat control device (30) for controlling and / or regulating the heat output of said At least one heating device (20, 22), the device being designed to carry out a process according to any one of claims 1 to 12. ECU _y-12 -j28 (r TKW_SW = f (ALC_AN) t_ST_SW = f (TKW, A LC_AN) rCTR_IGK_ON_SW T SP_LOW T SP HIGH T SP_ST t TEM P_SP_LOW t SP_LOW_SW t SP HIGH SW KF1 A2 42 39A-Z-`-39B - -1-111 19191919 21212121 20 II 0000 Z1Z2Z3 13 FIG 1 FT TKW> ES KF2 24 AS 41 LSU-44 ND 37 36 HCU 2/2 Si <Indicium for impending start yes CTR IGK ON> CTR IGK ON SW t SP HIGH utlupen? S12 513 ja t Sutlupen? SP LOWS7 58 no S S18 no Heat of T SP LOWT SP HIGHTSPST S16 S9 hoj _SP_LOWhoj t_SP_HIGH S2jaSi Cold start system watery? t_ST T KW, ALC_AN yes S4 lActivation HCU otor in progress. LV ERU = 1 no i ngp> <LV_IGK = 156 S no S Engine off start LV ST_END = 1? S17 and 511 i1LVIGK1 = i? yes no high CTR_IGN_ON yes no S3 Deactivation HCN no t —WAIT no TSPAST 519 FIG 2