Motor vehicle with a hybrid drive

The invention concerns a motor vehicle with a hybrid drive, which consists of an internal-combustion engine and of a battery powered electrical machine. With a well-known such motor vehicle (German Offenlegungsschriftl917581) the drive axle is propelled by an electric motor. This electric motor is fed from a battery, which is charged by a generator. For the drive of the generator the internal-combustion engine serves. Since the internal-combustion engine is loaded only by the generator, it is possible to in-regulate it on a constant number of revolutions and an almost constant load so that the emission of harmful exhaust gases becomes minimal. A in such a way equipped motor vehicle can cover short distances covered also completely without use of the internal-combustion engine, whereby the electric motor from the battery is fed, without this will nachgehden. A such motor vehicle drive is relatively complex, because two electrical machines are necessary, i.e. the driving motor and the generator serving for the shop of the battery. Both electrical machines must be laid out approximately fiir the same electrical achievement. The invention is the basis the task to create a less complex hybrid drive for motor vehicles without affecting thereby the favorable characteristics of the hybrid drive regarding the emission of harmful exhaust gases unfavorably. This task is solved in accordance with the invention thereby that dependent on the difference between necessary road performance and of the internal-combustion engine of output as engine or as generator operable electrical machine with its motor shaft propels at least one drive wheel of the motor vehicle and that the crankshaft of the internal-combustion engine over a first clutch with the driveshaft is connectable. With this training form of a hybrid drive thus a only one electrical machine serves the battery at the same time as driving motor and as generator for the shop. If the first clutch is not in the interference, alone the electrical machine propels the drive wheels. This Betriebszustaud is preferably selected during a city trip of the motor vehicle. Against it if the first clutch is in the interference, then the internal-combustion engine propels the drive wheels of the motor vehicle over the motor shaft of the electrical machine. The vehicle is started in principle only with the help of the electrical machine. Only if a certain driving speed is reached, the first clutch is brought in interference and the internal-combustion engine in enterprise is set. As soon as the internal-combustion engine is in enterprise, it can be regulated on full load. If it delivers thereby more achievement than at this moment for applying the road performance is necessary, then the electrical machine is operated as generator and charges thereby the battery up. This operating condition is selected appropriately during cross-country trips, during which a stronger emission of harmful exhaust gases is not so critical. From the German disclosure writing 1630475 already a hybrid drive is i°ür a motor vehicle well-known, with which likewise two engines affect a common wave, i.e. an electric motor and a hydraulic motor. The electric motor is fed thereby from batteries and the hydraulic motor from a Drttckspeicher. The hydraulic motor serves to apply with peak loads the necessary torque. During this well-known arrangement after the German disclosure writing 1630475 the common wave of the two engines can be separated by a Kuppluug from the drive wheels. If this clutch is except interference, the hydraulic motor can be propelled by the electric motor and operated as pump with stop of the vehicle. It fills thereby the accumulator. In comparable way loading of the batteries is possible with the hybrid drive after the invention, if between motor shaft of the electrical machine and at least one drive wheel a second clutch is arranged, which is operatable preferably only with stop of the motor vehicle. It is possible in this case to load the batteries serving as electrical energy storage nnabhängig from the electrical lighting system. It proves during this arrangement of the invention as particularly favourable that one can do without an additional turning engine for the internal-combustion engine. If the second clutch is except interference, actually the electrical machine serving for the drive of the motor vehicle can be used also as turning engine for the internal-combustion engine in the stop of the motor vehicle. Further details and appropriate further educations are below descriptive and described on the basis a remark example represented in the design more near. The design shows a motor vehicle with a hybrid drive in accordance with the invention in schematic representation. The motor vehicle points two drive wheels --16-- up, between those a Differenfialgetriebe --15-- is arranged. An internal-combustion engine --10-- a crankshaft possesses --19--, those over a first clutch--11-- actuated with a driveshaft --18-- is connectable. The driveshaft--18-- heard to an electrical machine --12--. The two connections of the electrical machine --12-- are with a battery --17-- connected. The driveshaft --18-- in addition is over a second clutch --13-- actuated with a cardan shaft --14-- connectable, those for the drive of the differential gearing --15-- serves. With the descriptive hybrid drive three can different operating condition be adjusted, by bringing a clutch or both clutches in interference. With the first operating condition is the first clutch --11-- except interference and the second clutch --13-- is in the interference. This operating condition is used for the city trip, during which it depends on minimum emission of harmful exhaust gases. The electrical machine --12-- drives in this operating condition alone the two drive wheels --16-- on and thereby the battery unloads --17--. The radius of action of the motor vehicle depends on battery capacity. The highest driving speed in city traffic becomes by the achievement of the electrical machine --12-- besümmt. In the second operating condition, which is used particularly for the cross-country trip, are both clutches --11 and 13-- in the interference, so that mainly the Brennkraftmaschiue --10-- the drive of the motor vehicle takes over. On steep hilly stretches or for rapid accelerating the electrical machine can --12-- to the support of the internal-combustion engine --10-- with the vehicle drive to be consulted. Turned around the electrical machine can during trips into Gef'ällstrecken and when retarding the vehicle --12-- as generator to be used and the battery --17-- load again. It is very appropriate, if one the internal-combustion engine --10-- for somewhat larger achievement dimensioned than it is necessary during a normal cross-country trip. Then the electrical machine can --12-- during the whole cross-country trip achievement of the Brennkraftmaschlne take over and the battery --17-- load. The starting process runs off during the cross-country trip exactly directly as alone during the city trip, i.e. using the electrical machine --12--. If then a speed is reached by e.g. 30km/h, the first clutch becomes--11-- engaged and the internal-combustion engine --10-- thus started. With the two operating conditions described so far is the second clutch --13-- constantly in the interference. With the third operating condition against it is except interference and the first clutch --11-- is in the interference. In this third operating condition the battery can be re-charged with stop of the vehicle, if straight no mains connection is available. Normally the battery, if it unloaded itself during longer city trip too strongly, from the lighting system is again charged with the help of a battery charger, since while the loading at all no harmful exhaust gases develop in such a way. In emergencies however also the internal-combustion engine can --10-- in the descriptive way to the shop of the battery --17-- are consulted. For this purpose the internal-combustion engine becomes --10-- first of the electrical machine --12-- turned, so that an additional turning engine for the internal-combustion engine is unnecessary. The small Leistnng necessary for turning the engine knows from the battery ---17-- still to be taken, even if the battery is already so far unloaded that a drive of the vehicle from it is no longer possible. The electrical machine --12-- can be designed as d.c. machine or as three-phase alternating current asynchronous machine, as it admits from other electrical vehicle drives is. The d.c. machine can directly from the battery --17-- are operated. For the three-phase alternating current asynchronous machine against it a special inverter is necessary. But however the external dimensions and the weight are smaller than with a d.c. machine of same achievement with the three-phase alternating current asynchronous machine. In the case of use of a d.c. machine all well-known Steuerungsverfahreu, so e.g. the resistance control without or with field weakening can be used and the impulse control over transistors or thyristors. Depending upon the Verwenduugszweck a series-wound motor or a shunt-wound electric motor can be used. The descriptive arrangement of a hybrid drive for a motor vehicle erfiilk thus the demands initially placed. The additional generator necessary with the conventional hybrid drive f'ällt away. Nevertheless can be driven on shorter distances completely without waste gas emission. Also on cross-country distances the waste gas emission is smaller than with a vehicle, which is propelled alone by an internal-combustion engine, because the internal-combustion engine is loaded evenly. This even load agitates from there that the electrical machine always takes over a part of the achievement of the internal-combustion engine. This portion is increased, if the load decreases by the drive wheels. Such an enterprise with almost constant load corresponds to the initially mentioned enterprise of the internal-combustion engine with the conventional hybrid drive and leads to a substantial decrease of the waste gas emission. The application of the descriptive arrangement of the hybrid drive is not limited to road vehicles. Also rail-mounted vehicles, motorboats and submarines can be equipped with a such hybrid drive. With motorboats noise protection regulations can be fulfilled with a hybrid drive; with submarines for the submerged operation the electrical machine is used and for the Überwasserfahrt the internal-combustion engine for the drive.