DE2917139A1 - METHOD AND DEVICE FOR OPERATING A MOTOR VEHICLE WITH AN INTERNAL COMBUSTION ENGINE - Google Patents

Description

LuK slats and

Coupling construction GmbH

Industiestraße 3

P.O. Box 136O - 0364 D

758O Bühl / Baden

Method and device for operating a motor vehicle with an internal combustion engine

The invention relates to a method for operating a motor vehicle, one from an internal combustion engine existing drive motor to compensate for the degree of irregularity the rotating movement serving, the crankshaft to and uncoupling flywheel is assigned. The invention further relates to a device for carrying out the method as well as a device according to the method operated motor vehicle.

It is already a method for operating internal combustion engines in motor vehicles has been proposed to be in such operating conditions in which the drive motor does not drive the vehicle - e.g. B. when coasting and idling - and if a centrifugal mass that can be coupled and uncoupled from the crankshaft is still rotating at a minimum speed, the connection between the drive motor

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and turn off the flywheel and shut down the engine to save fuel. The flywheel then continues to rotate as an energy store, and when the above-mentioned driving conditions are terminated, the system slips Coupling the flywheel to the internal combustion engine started again. This method is particularly suitable for the operation of relatively small vehicles whose road safety is not impaired by the standstill of the drive engine will.

The present invention was based on the object of the lowest possible even with larger vehicles Energy, especially fuel consumption after the To ensure the type described at the beginning without affecting road safety.

According to the invention this is achieved in that in such operating states in which the engine does not drive the vehicle while it is in motion, e.g. B. when decelerating, when braking, when Overrun or the like., The drive train between the drive wheels and the engine is interrupted and the engine with coupled flywheel with a minimum speed, such as. B. the idle speed continues to rotate, whereas in the case of brief standstills, such as B. traffic lights or the like, the

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drivetrain between the drive wheels and the Internal combustion engine also interrupted, the flywheel mass that can be coupled to and uncoupled from the internal combustion engine however, is uncoupled and the internal combustion engine is stopped while the flywheel continues to rotate and this is used to start the internal combustion engine - If the drive train between the drive wheels and the internal combustion engine is interrupted - this again is coupled.

Such a method on the one hand enables minimal fuel consumption, on the other hand it guarantees safe operation of the motor vehicle at the same time, since at least the ancillary and auxiliary units driven by the internal combustion engine, such as. B. for power steering, braking assistance, but also the alternator and other units are driven and their effects are available, at least as long as the vehicle is in motion »With Otto engines and if a vacuum brake servo device is available ₉ remains during the braking force-boosting effect of the driving operation, since the source for the generation of the negative pressure continues to be operated »

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To the internal combustion engine when necessary after termination the intended short downtimes, such as stopping at traffic lights or the like. To start again, what by coupling the flywheel, z. B. depending on the actuation of the accelerator pedal can be controlled, and the required kinetic energy of the To have a flywheel always available, it can be advantageous if, during the operating states, in which the motor vehicle is stationary and the flywheel is decoupled from the internal combustion engine and should continue to run, this is kept at a certain speed by an electric drive motor, which is sufficient to ensure that the drive motor is started when it is coupled down. It can do it the electric motor constantly with low current or with short successive pulses with current fed and thus kept the flywheel at an at least approximately constant speed level will. The electrical energy required for this is extremely low.

Another possibility, the kinetic energy of the flywheel for restarting the internal combustion engine to keep at a certain minimum level and the existing energy budget for this the vehicle is practically not weakened,

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consists in the fact that the flywheel mass is undershot a certain limit speed is accelerated again to a higher speed level by the flywheel the internal combustion engine is coupled again in order to start it up and at a higher speed to be brought and wherein when a certain target speed is reached, the flywheel is uncoupled again and the internal combustion engine is stopped. The flywheel then continues to rotate freely and becomes practically only slowed down slightly by the friction of their bearings and the air resistance.

Another possibility, with as little energy as possible, the one required for restarting Maintaining kinetic energy of a flywheel is that the flywheel is at stationary drive motor and when a certain lower speed limit is reached via means, such as a Starter motor, is brought to a higher speed level and the means upon reaching a certain Target speed can be switched off again. The starter motor can be a friction wheel starter, its friction wheel can be brought into engagement with the flywheel in order to accelerate it to the higher target speed.

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To keep up for restarting an internal combustion engine required kinetic energy of the flywheel by an electric motor it can be advantageous if the centrifugal mass that can be uncoupled is the rotor of the electric drive machine and / or the starter motor. The stator can be on the internal combustion engine or on the transmission housing be attached. This inventive feature can be used in such arrangements in which the flywheel is concentric to the crankshaft of the internal combustion engine and rotatable relative to it provided, is used, as well as those in which the flywheel is on one of the crankshaft remote bearing is provided rotatably.

Furthermore, it can be advantageous if in the states in which the internal combustion engine is in operation is, the starter motor can be switched to generator operation. Such a device is particularly simple and reliable, as two ancillary or auxiliary units can be combined into one unit and no mechanical transmission means, such as. B. friction wheel, V-belt or the like. Between electric drive motor or generator and the flywheel are required.

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It can be useful if the Motor Gener ·; gate integrated flywheel rotor none Has windings and works according to the known reluctance principle. More options consist in building the motor-generator according to a linear principle or according to the Guyschen principle.

To carry out the method according to the invention for operating a motor vehicle, one from an internal combustion engine existing drive motor one to compensate for the degree of non-uniformity the centrifugal mass serving for the rotary movement is connected downstream, which is connected to the crankshaft by a clutch can be uncoupled and rotated in the uncoupled state relative to the crankshaft, can be advantageous Way suitable a device that has a switching or control device that is dependent of such operating states in which the engine does not drive the vehicle drives, such as B. when decelerating, when braking, when overrun or the like., In each case the drive train between the drive wheels and the engine interrupted via another clutch and the engine with the coupled flywheel switches to idle and which has a control that, in the event of brief stoppages, such as, for example, traffic light stops or the like

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Drivetrain between the drive wheels and the Internal combustion engine is also interrupted by the further clutch, but the engine stops and beforehand the flywheel to be able to start the engine again, via which a clutch disconnects from it and the flywheel continues to rotate and another switching device that is used to restart the Motor recouples the flywheel mass of the stopped motor and thus starts the motor when the accelerator pedal is actuated and wherein an electric drive device is further provided for first start of the engine, for which the device the flywheel in the disengaged state of both Clutches up to a certain target speed :! drives and by coupling the flywheel mass to the crankshaft - with an interrupted drive train between the drive wheels and internal combustion engine - this engine is cranked or started.

Based on the embodiment shown in the figure the invention is explained in more detail.

In the figure is a device 1 for implementation of the method for operating a motor vehicle is shown with a drive motor 2 consisting of an internal combustion engine and one of this internal combustion engine

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downstream flywheel 3 »which has a coupling 4, which has a not shown Actuation by the servo device 5 of the crankshaft 6 of the internal combustion engine can be coupled and uncoupled is. Via a further clutch 7 »which is also carried out via an actuation not shown in detail the servo device 8 is switched, the transmission 10 is connected to the motor 2 via the transmission input shaft 9 can be coupled and uncoupled.

The transmission 10 has drive shafts 11, 12 for driving the wheels 13, i4.

The device also has a starter motor 15 »which has a starter wheel, such as. B. a friction wheel 16 can drive when the switch 17 »z. B. via the ignition lock is closed.

To start the internal combustion engine 2 for the first time, so at the start of the journey, both clutches 4, 7 must be disengaged, which is when the switch is operated takes place via the servo devices 5 and 8 controlled by the switching or control device 18. the stationary., ", rotatable relative to the crankshaft 6 Mounted flywheel 3 can now be powered by the switch 17 and the switching or control device 18

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supplied starter 15 via the friction wheel 16 to corresponding Starting speed are brought, whereupon the clutch 4 is closed via the servomotor 5 is determined as soon as the starting speed via the speed sensor 19 and from the switching or control device 18 the servomotor 5 the corresponding command receives the flywheel 3 of the crankshaft 6 of the internal combustion engine 2 is coupled and thus throws it on ..

In normal driving mode, when the internal combustion engine drives the vehicle, the gear shift clutch is closed. To change gears can be known in and of itself Way, the clutch 7 can be opened and closed again via the servomotor δ.

In such operating states in which the engine 2 does not drive the vehicle in motion, such as. B. when decelerating, braking, coasting or the like. So every time the accelerator pedal 20 is released and the contact 21 is closed, the drive train between the drive wheels 13, lh and the engine 2 is interrupted via the clutch 7, namely via the switching or control device 18. Depending on the above-mentioned operating states - and when the two measuring transducers 22 give rotary motion to the switching or control devices

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direction 18 report - the servo motor 8 a control signal, which the disengagement of the clutch 7 and thus the Separation of the motor - with the flywheel 3 coupled from the drive wheels 13 »14 effected. By doing it The position corresponding to the accelerator pedal - the throttle valve in carburettor engines - the engine 2 thus runs at idle. The fuel consumption is limited to a minimum, the effect on driving safety required auxiliary units, such as brake servo, Steering servo and alternator are retained.

The disengagement of the clutch 7 and thus also the above economical operation while maintaining full However, operational reliability could also be a function of changes in torque, d. i.e. as soon as in the drive train no drive torque is transmitted from the engine 2 to the drive wheels and / or each time one occurs Pushing operation or every time a change from pulling to pushing operation occurs.

It would also be possible to disengage the clutch 7 as a function of the changes in the internal combustion engine z. B. to control negative pressure generated in the intake duct. This can be done regularly if of any negative pressure level, once present

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an increase of the same takes place. Instead of depending on torque or pressure measuring devices the uncoupling of the transmission also takes place every time the accelerator pedal or one actuated by it Element is moved back from a position once it has been assumed, in the sense of "less gas". This can be done z. B. by a drag switch 23, with the help of a freewheel or the like. By such measures or means is guaranteed that not only when the accelerator pedal is fully retracted this fuel-saving Operating state is brought about, but already when part load or overrun is initiated will.

In the event of brief downtimes, such as B. traffic lights or the like. Report the speed sensor 22 "standstill" and it is also the drive train between the drive wheels 13, 1 ^ · and the internal combustion engine 2 by the further clutch 4, via the servo motor 8, from the switching or control device 18 interrupted so that the flywheel 3 can continue to rotate relative to the crankshaft 6 and then the internal combustion engine 2 is stopped. This is done via the switch or Control device 18 controlled fuel supply and / or ignition circuit breaker Zh.

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ORlGiNAL i

To restart the engine when you want to continue driving, the flywheel 3 is recoupled to the engine via the clutch h and thus the engine is started. This can take place as a function of the actuation of the accelerator pedal via the switches 21 or 23, in that the servomotor 5 is actuated via the switching or control device.

So that it is guaranteed in the case of brief stoppages that the stored in the flywheel 3 kinetic! energy is sufficient to ensure a smooth restart of the motor 2, the flywheel 3 is kept above a certain speed level.

This can be done in that when the Schaltbzw. Control device 18 from the measuring transducer 19 values receives, which correspond to falling below a certain lower limit speed and from the encoder "Motor standstill" is reported, the switching or control device 18 via the servomotor 5 closes the clutch 4 and thus the recoupling of the flywheel 3 to the engine 2 causes, whereby the The engine is started and thus the flywheel is accelerated again to a higher speed and when it is reached this higher speed another control signal

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is emitted by the transducer 19, whereby the switching or control device 18 and the servomotor 5 causes the clutch k to be disengaged again and thus the free rotation of the flywheel 3 and at the same time stops the motor 2 again via the device Zh.

Another possibility of keeping sufficient kinetic energy of the flywheel 3 available for restarting the engine 2 is that the starter 15 is switched on via the device 18 at a lower limit speed reported to the switching or control device by the transducer 19 will. This can e.g. B. be designed as a screw drive starter and drive the flywheel via the friction wheel 16 until the Schaltbzw. Control device 18 switches off the starter motor as soon as the corresponding speed is determined via the encoder 19. The starter motor 15 could, however, also keep the centrifugal mass 3 »after the lower limit speed has been reached or, as soon as the motor 2 is at a standstill, always keep it at a certain speed. The starter 15 can then be switched off via the switching or control device 18 as a function of the actuation of the accelerator pedal of the clutch h or the rotational movement of the crankshaft 6. The internal combustion engine is started for the first time

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by pressing switch 17

The figure also shows a variant in which the flywheel 3 is part of an electrical machine Z6 for starting the drive motor 2. The flywheel 3 is designed as a rotor of the electrical machine and a stator 27 is provided concentrically around the rotor. The first one

2
Starting of the drive motor ^ is effected by actuation of the switch 17 via the switching and control means 18, wherein the couplings _t h 7 via the associated servo motors 5 »8 i ⁿ the manner already described are disengaged. The stator 27 is excited and when a certain speed is reached, which is passed on to the switching or control device 18 via the measuring sensor 19, the latter causes the clutch 4 to be closed by the servomotor 5. The drive motor is thus started. The power supply to the stator 27 is interrupted via the switching or control device 18 and remains so as long as the switching or control device does not receive a signal from the measuring transducer 19 that the speed has fallen below a certain limit. Falling below a certain limit speed and the standstill of the crankshaft 6, which is reported by the encoder 25, causes the power supply to the stator 27, whereby the kinetic

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Energy of the flywheel 3 for restarting the drive motor 2 is maintained, which can be done, for example, by actuating the accelerator pedal 20. The power supply can be continuous or pulsed or in such a way that the flywheel 3 is brought to a speed well above the required starting speed and can rotate freely until the lower limit speed is reached again.

The electrical machine 26 can, however, also be switchable to a generator as a function of a Minimum speed of the drive motor, which is determined via the encoder 25 and sent to the switching or control device 18 is passed on. From the switching or Control device is used to switch from Generator to motor operation and vice versa.

The motor generator 26 can work according to the Guyschen principle or according to the linear motor principle.

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Claims (11)

LuK slats and Coupling construction GmbH Industriestrasse 3 P.O. Box I36O _m 036h D 758O Bühl / Baden Claims 1 «Procedure for operating a motor vehicle with one consisting of an internal combustion engine Drive motor, one used to compensate for the degree of irregularity in the rotary movement A flywheel mass is assigned and which can be coupled and uncoupled from the crankshaft, characterized in that that in such operating states in which the engine (2) does not drive the vehicle drives, such as B. when decelerating, braking, overrun or the like. The drive train between the drive wheels (13 »1 * 0 and the motor (2) is interrupted and the motor (2) with coupled flywheel (3) with a minimum speed, such as B. the idle speed continues to rotate, whereas with brief stoppages, such. B. Stop at traffic lights or the like. The drive train between the drive wheels (13 »1 * 0 and the internal combustion engine 03G045 / 0365 machine (2) also interrupted that of the internal combustion engine (2) can be coupled and uncoupled flywheel (3) is uncoupled and the internal combustion engine (2) is stopped while the flywheel (3) continues to rotate and this is used to start the internal combustion engine (2) - when interrupted Drive train between drive wheels (i3fl * 0 and the internal combustion engine (2) - this is coupled again. 2. The method, in particular according to claim 1, characterized in that the flywheel (3) in the brief standstills of the motor vehicle by an electric drive motor (15 »26) on a is maintained at a certain speed, which is sufficient to connect to the drive motor (2) when decoupling to ensure that it is started. 3 · Method, in particular according to claim 1, characterized in that the flywheel (3) when at a standstill Drive motor (2) is freely rotatable and when falling below a certain limit speed is accelerated again to a higher speed level by the flywheel (3) of the internal combustion engine (2) is re-coupled in order to start this up and at the same time to a higher one 030045/0365 Speed to be brought and the flywheel when a certain target speed is reached (3) is uncoupled again and the internal combustion engine (2) is stopped. 4. The method according to claim 1, characterized in that the flywheel (3) when the drive motor (2) _{f is stationary during the short downtimes}
and reaching a specific lower speed limit by means of how a starter motor (i5 »26) is brought to a higher speed level and the means (15» 26) are switched off again when a specific target speed is reached. 5. Method according to claim 1 and 4, characterized in that the starter motor (15) is a friction wheel starter is, the friction wheel (16) with the flywheel (3) can be brought into engagement to this on to accelerate the target speed. 6. The method, in particular according to one of claims 1 to 4, characterized in that the uncoupling Flywheel (3) the rotor of the electric drive machine (26) and / or the starter motor (26) forms. Oc-- G45 / 0365 7. The method, in particular according to one of the claims 1 to h and 6, characterized in that in the states in which the internal combustion engine (2) is in operation, the starter motor (26) can be switched to generator operation. 8. The method, in particular according to one of the claims 1 to h and 6 or 7 »characterized in that the motor generator (26) with an integrated flywheel rotor (3) works according to a reluctanζ principle. 9. The method, in particular according to one of the claims 1 to h and 6 or 7 »characterized in that the motor generator (26) operates on a linear principle. 10. The method, in particular according to one of the claims 1 to h and 6 or 7 »characterized in that the motor-generator (26) works according to the Guyschen principle. 11. Facility for carrying out the procedure for Operation of an internal combustion engine, in particular according to one of claims 1 to 10, wherein a drive consisting of an internal combustion engine 030045/0365 motor one to compensate for the degree of irregularity the rotating movement serving centrifugal mass is connected downstream, which by a coupling of the The crankshaft can be disconnected and is in the disconnected state is rotatable relative to the crankshaft, characterized in that the device (i) has a switching or control device 18 which, depending on such operating states, in which the engine (2) does not drive the vehicle in motion, such as. B. in the event of delays, when braking, overrun or the like, the drive train between the drive wheels (13 »1 ^) and interrupts the motor (2) via a further coupling (7) and the motor (2) with the coupled-on one The flywheel (3) switches to idle and which has a control (22,18) which, in the case of short-term Standstills, such as B. traffic lights or the like. The drive train between the drive wheels (13 | 1 ^ -) and the internal combustion engine (2) also interrupts the further clutch (7), the engine (2) However, the flywheel (3) is stopped and the flywheel (3) »to be able to start the engine again via the a clutch (4) uncouples from this and the flywheel (3) continues to rotate and another Switching device (21,23 »18), which for restarting the motor (2) the stopped motor (2) the Ü3C 045/0365 The flywheel (3) is coupled again and thus starts the motor (2) when the accelerator pedal (20) is pressed and wherein an electric drive device (15, 26) is also provided for the first time Starting the engine (2), for which the device (15 »26) the flywheel (3) when both are disengaged Couplings (4,7) up to a certain target speed drives and through. Coupling of the flywheel (3) to the crankshaft (6) - with an interrupted drive train between drive wheels (13f1 * 0 and internal combustion engine (2) - this motor (2) is started or started. 030045/0365