CN102753814A - Controller, starting device, and method for operating the controller - Google Patents

Abstract

The invention relates to a method for operating a controller (5) for a starting device (1) of an internal combustion engine (2), wherein the starting device (1) comprises an electric motor (3), in particular a starter motor (3), and a coupling device (4), in particular having a starter pinion (7) for engaging in a crown gear (8) of the internal combustion engine (2), and wherein the electric motor (3) and the coupling device (4) are actuated separately and the electric motor (3) is coupled to the rotating, in particular coasting down, internal combustion engine (2). In order to bring the internal combustion engine (2) into a startable state as quickly and safely as possible, a time curve of an actuation of the electric motor (3) and the coupling device (4) is determined and carried out according to a selected operating strategy.

Description

Controller, starting device and method for operating the controller

technical field

The invention relates to a method for operating a controller for a starter device of an internal combustion engine, wherein the starter device has an electric motor, in particular a starter motor, and a coupling device, in particular a starter for meshing with a gear ring of the internal combustion engine Machine gears, as well as motors and couplings in which the motors are activated separately, and the motors are coupled to a rotating, in particular idling-running (auslaufend) internal combustion engine. The invention also relates to a controller, a starting device and a computer program product.

Background technique

It is known to start an internal combustion engine, in particular a motor vehicle, by means of a starter device which comprises an electric machine as starter motor. For starting, the internal combustion engine and the starter motor are coupled by means of a mechanical coupling device comprising a starter gear of the starter motor and a gear ring of the internal combustion engine by engaging the starter gear into the gear ring by means of a clutch relay.

It is also known, for example to reduce fuel consumption or exhaust emissions, to switch off the internal combustion engine during a short stop phase of the motor vehicle, for example at a red traffic light, and to start it up again in order to continue driving. In this start-stop operation, the starter motor can not be coupled to the internal combustion engine until the internal combustion engine is started again. In order to reduce the time delay when restarting, the starter motor can optionally be coupled with the internal combustion engine which is still idling, i.e. rotating, after disconnection, i.e. this is done in such a way that the starter gear meshes into the rotating gear circle.

Furthermore, it is also known, in particular, to activate the starter motor and the coupling device separately with the controller in such a way that the electrical contacts for the use of the The starter gear engages the engagement relay in the gear ring, and the starter unit includes the controller.

DE 10 2006 011 644 A1 describes a device and a method for starting a starter motor by meshing a starter gear into a coasting gear ring of an internal combustion engine.

Contents of the invention

It is therefore the object of the present invention to develop a controller, a starting device, a computer program product and a method for operating a controller of the aforementioned type in such a way that an internal combustion engine can be started as quickly and reliably as possible, and thus comfortably.

This object is achieved according to the invention by the subject-matter of claims 1 , 8 , 9 and 10 . The dependent claims define preferred developments of the invention.

The idea of the invention is to determine and execute the timing sequence for triggering the electric motor and the coupling according to the selected operating variant. The time sequence can thus be adapted to the boundary conditions and/or influences of the internal combustion engine and/or the starting device, for example a certain configuration or state, or a correspondingly suitable sequence can be selected so that the electric machine and the internal combustion engine are as reproducible and comfortable as possible, ie In particular, a low-noise, low-wear and low-vibration coupling is achieved. At the same time, the time sequence can be determined in such a way that the coupling parts, for example the starter gear and the gear ring, rotate relative to one another at essentially synchronous peripheral speeds during coupling, in order to achieve a comfortable, fast and reliable meshing.

Here, "rotate synchronously with respect to each other" or "speed synchronously" means in this context that the tooth frequencies of the starter gear and the gear ring are substantially identical. synchronous means before and after the rotating coupling parts to be coupled to each other, in particular the starter gear and the gear ring, respectively, have such rotational speeds that they do not have a significant speed difference at their mutual intentional or actual points of contact . For the example of starter gears and gear rings, this means that the ratio of the individual rotational speeds essentially corresponds to the ratio of the circumferences of the respective starter gears and gear rings, in particular the ratio of the number of toothings.

In addition, the time course can be calculated according to the operating scheme. Thus, for example, unforeseen influences can be taken into account. It is also possible to select a time sequence from a plurality of different, for example predetermined, in particular stored or permanently executed time sequences. The outlay for determining the time sequence can thus be reduced. For example, the different time sequences differ by a different sequence and/or different time intervals of the individual switching-on and/or switching-off times of the electric motor and coupling device. The triggering can thus be easily and flexibly adapted to different requirements, in particular to the dynamics of the internal combustion engine and/or the starter.

This object is achieved in that the controller is designed with an operating concept in order to determine a specific time sequence for triggering the electric motor and the coupling, in particular in accordance with the methods mentioned above or below. Furthermore, the object is achieved by a starting device which is designed in such a way that, depending on the operating concept, a certain time sequence for activating the motor and the coupling is determined, more precisely in particular according to the above-mentioned or below-mentioned method. The subsequent description of the controller and the method for operating the controller correspondingly also relates to the starting device and the method for operating the starting device.

According to a preferred embodiment, the operating concept takes into account the rotational speed and/or the inertia gradient of the internal combustion engine. The time sequence for triggering the electric motor and the coupling device can thus be determined particularly simply and advantageously in such a way that the coupling of the electric motor and the internal combustion engine is essentially rotationally synchronous and thus reliable, low-noise, low-vibration and low-wear, and also i.e. perform comfortably.

In order to more precisely determine the time course for a reproducible, comfortable connection as much as possible, preferably a future connection moment is predicted and the time course is determined taking into account the prediction of the connection moment, in particular wherein the time course is determined on the basis of at least one other prediction Make the time flow match. Prediction of the moment of coupling enables the movement of the internal combustion engine, electric machine and coupling to be taken into account, in particular with respect to their temporal behavior, i.e. dynamics, in order to achieve as accurate a coupling as possible when the coupling parts rotate substantially synchronously with rotational speed Internal combustion engines and electric motors. The connection time can be predicted more accurately and the synchronization improved by at least one other prediction, in particular closer in time to the connection time.

The moment of coupling is the moment in coupling where the coupling parts, in particular the starter gear and the gear ring, come into contact. The more accurate the synchronization of the peripheral speeds of the coupling parts at the time of coupling, the less wear, vibrations and/or noise during coupling.

It is preferably achieved by selecting the switch-on time of the electric motor temporally before the switch-on time of the coupling device, so that the electric motor is already activated temporally before the coupling device is activated. As a result, the electric machine can be switched on reliably before the coupling time, in particular in order to synchronize the rotational speeds of the starter gear and the gear ring as much as possible with respect to their rotational speeds and to reduce wear during coupling.

According to a preferred method, the electric motor and the coupling device are activated in a temporally overlapping manner, ie at least temporarily simultaneously, according to a first operating variant in a specific temporal method sequence. As a result, the time sequence for actuating the electric machine and the coupling device can be shortened and the starting of the internal combustion engine can be accelerated.

Furthermore, such a time sequence with temporally overlapping activations is advantageous in particular for rapid coasting of the internal combustion engine, in which the operating duration and/or the operating speed, ie in particular the meshing speed, of the electric machine is substantially in a wide operating range. is kept constant so that the push-out duration of the engaging relay of the coupling device, that is to say the coupling duration, can be predicted. (Other contents of the inventor may be described here)

The coupling duration denotes the time duration between the switch-on time and the coupling time of the coupling device. In this case, the engagement period is essentially based on the push-out period of the engagement relay, ie in particular the period for moving the starter gear in the rest position in the uncoupled state until the starter gear and the gear ring come into contact.

According to a preferred method, the electric motor and the coupling device are activated temporally in a specific temporal method sequence in such a way that the switch-on times of the motor and the coupling device are spaced apart in time. Interactions can thus be reduced, for example, by the switching currents and by the voltage fluctuations associated therewith, since the individual switching currents likewise occur sequentially in time.

According to another preferred alternative method, in a specific time sequence according to the second operating concept, the electric motor and the coupling device are activated successively in time, that is to say sequentially, to be more precise, in particular following the The defined interval duration between triggering and triggering of the coupling device. To be triggered sequentially in time means that the switching-off time of the electric motor is selected to precede the switching-on time of the coupling device in time, or vice versa. Interactions can thus be avoided, for example, by operating currents and voltage fluctuations associated therewith.

Furthermore, in this alternative method, it is particularly preferred that the motor is triggered temporally before the coupling device in that the motor is in particular selected so that the switching-off time of the motor precedes the switching-on time of the coupling device, i.e. the motor and The coupling devices are not triggered overlapping in time. Thus, the coupling device is not affected by the high current consumption of the electric motor. Thus, the power of the coupling device remains constant and the duration of the coupling is substantially constant, so that the coupling moment can be predicted more accurately and the course of time can be more precisely determined. The coupling of the electric machine and the internal combustion engine, ie also the starting of the internal combustion engine, can thus be replicated better.

In order to be able to react to the time-varying coupling instants that are being sought, the temporal method sequence preferably includes at least a defined pause duration between the activation of the electric motor and the activation of the coupling device. Thus, the coupling duration and the actuation duration can be shifted in time relative to each other by means of the pause duration, the electric motor can be triggered more precisely and reproducibly and the relay can be engaged, so that substantially synchronous rotational speeds of the coupling parts are achieved at the coupling moment. In this case, the run-on duration means the time required for starting the electric machine at this rotational speed.

Furthermore, a time course determined on the basis of a first prediction can be technically easily adapted to a subsequent second prediction by preferably only adapting the pause duration. The pause duration can be adapted more simply than the engagement duration or the switch-on duration by changing the corresponding switch-on moment in time. Correspondingly, a change in the definition of the start-up period and the engagement period can be realized with only a relatively large circuit- and control-technical outlay. In addition, it is possible to respond to a shortened or extended switch-on or coupling duration, for example due to external influences, temperature or aging phenomena, by means of the intermittent duration, in order in particular to ensure the desired coupling moment and/or to achieve the desired coupling moment. Better synchronized peripheral speeds.

According to a further preferred embodiment, when the electric motor is activated, the actual switch-on time is detected, on the basis of which the switch-off time of the electric motor is determined and adapted. It is thus possible to take into account switching delays between the switch-on time of the electric motor and the actual switch-on time from which the electric machine is actually powered, and increase the temporal accuracy of the time sequence. The connection is therefore also more reliable, less wear-resistant, noise-free and therefore more comfortable.

Said object is also achieved by a computer program product which can be loaded in a program memory with program instructions of a microcomputer in order to carry out all the steps of the method described before or after, in particular when executed in a controller computer program product. Here, the microcomputer is preferably a component of the controller, wherein the controller, in particular for several control devices in the system, can have several microcomputers and memories as well as several computer program products or be distributed among several control units. A computer program product implemented on a device. The computer program product requires only few or no additional components in the controller and can preferably be executed as a module in an already existing controller. A further advantage of the computer program product is that it can be easily adapted to individual and specific customer requirements, and the improvement or optimization of individual method steps can be carried out cost-effectively and with little effort.

It goes without saying that the features mentioned above and still to be explained below can be used not only in the respective combination indicated but also in other combinations.

Description of drawings

The present invention will be described in detail below with reference to the accompanying drawings. The accompanying drawings show:

Fig. 1 shows the starting device of controller;

Figure 2 shows a method for operating a controller;

Figures 3 and 4 illustrate another method for operating the controller, and

5 and 6 show another method for operating the controller.

Detailed ways

FIG. 1 shows a starting device 1 for an internal combustion engine 2 comprising a starter with a starter motor 3 and a coupling device 4 , wherein the coupling device 4 comprises an engagement relay 6 and a starter for engagement in a gear ring 8 of the internal combustion engine 2 machine gear7. The starter device 1 and the internal combustion engine 2 are arranged in a motor vehicle (not shown) and are designed for start-stop operation of the internal combustion engine 2 . As described below, in start-stop operation, after the internal combustion engine 2 has been disconnected, the starter gear 7 meshes into the still rotating idler internal combustion engine 2 , that is to say into the rotating gear ring 8 , in order to pass the internal combustion engine 2 A high availability is achieved with respect to the possible early onward resistance of the motor vehicle.

Furthermore, the starter device 1 comprises a controller 5 with a microcomputer 9 , a memory 10 and two power switches 14 , 15 designed to activate the engagement relay 6 and the starter motor 3 individually. In an alternative exemplary embodiment, instead of the power switch 15 , the internal combustion engine 2 can be powered via a switching relay, wherein the switching relay itself can be triggered, for example, via the power switch 15 .

Due to the power supply to engagement relay 6 via power switch 14 , starter gear 7 is meshed into gear ring 8 via lever 11 , independently of the power supply to starter motor 3 by means of power switch 15 . In this case, starter device 1 is supplied with electrical power by a battery 13 of the motor vehicle.

Furthermore, the control unit 5 has an interface 12 to an engine control unit and to another control unit of the motor vehicle, in particular to detect the rotational speed of the internal combustion engine 2 .

FIG. 2 shows a method for operating the controller 5 , in which in step S1 a future connection point in time t4 to be reached is predicted. For this purpose, the rotational speed or optionally the rotational speed gradient of the internal combustion engine 2 is detected via the interface 12 in order to predict the engagement time t4 at which the internal combustion engine 2 should have a suitable rotational speed for the engagement. Engagement time t4 describes the time from which starter gear 7 , which is moved towards gear ring 8 by means of engagement relay 6 , touches gear ring 8 for meshing.

In step S2 , as shown by way of example in FIGS. 3 to 6 , a specific time sequence is determined by back calculation from the predicted connection time t4 , taking into account the start-up duration and the connection duration. For this purpose, the switch-on and switch-off times t1 and t3 for supplying the starter motor 3 by means of the power switch 15 and the switch-on times t2 for supplying the clutch relay 6 by means of the power switch 14 are respectively determined, more precisely In other words, it is determined that at the predicted coupling time t4 starter gear 7 and gear ring 8 rotate as synchronously as possible with respect to peripheral speed.

In step S3 , starter motor 3 and coupling device 4 are finally triggered by controller 5 according to the time sequence determined in step S2 . In summary, the steps described before and after are executed by the computer program product stored in the memory 10 using the microcomputer 9 . In this case, the starter gear 7 is moved towards the phase gear ring 8 for meshing during the coupling duration. Once the starter gear 7 and the gear ring 8 are in contact, the coupling moment t4 is reached and steps S1-S5 end.

Otherwise, in step S4 a further prediction of the coupling time t4 is carried out by the controller 5, in particular in order to take into account disturbances, such as the temperature of the starter motor 3, which may cause the actual coupling time to be different from the predicted coupling time. Offset of t4.

In step S5, the previously determined time sequence is adapted on the basis of the further prediction carried out in step S4, and then converted with step S3 in order to ensure a comfortable, in particular low noise, low vibration and low wear, for starting the internal combustion engine 2 meshing.

FIGS. 3 and 4 and FIGS. 5 and 6 show respectively an embodiment of a determined time method flow for the first and second operating scenarios of the method used by the operating controller 1, wherein the starter motor 3 and the coupling The device 4 is activated individually in order to couple the starter motor 3 and the deactivated and coasting, ie still rotating, internal combustion engine 2 to one another. In the method, as described below, the starter motor 3 and the internal combustion engine 2 are coupled to each other as comfortably as possible, in particular with little noise, wear and vibration, by meshing the starter gear 7 into the rotating gear ring 8 .

Here, the coupling time t4 at which the gear wheel 8 has a specific rotational speed n2 suitable for coupling is predicted by the computer program product executed in the microcomputer 9, and is calculated from the coupling time with respect to the time axis by an inverse algorithm A specific time sequence for activating starter motor 3 and engaging relay 6 is determined according to the operating scheme. In particular, the engagement duration and the actuation duration which are substantially determined by the design of the starter device 1 are taken into account.

In addition, the course of the push-out duration of the engagement relay 6, the activation duration of the starter motor 3 and the rotational speed n2 of the internal combustion engine 2 are subject to certain fluctuations, which are determined, for example, by aging effects, temperature and/or the voltage of the battery 13, so that the predicted Engagement time t4 has certain uncertainties, namely due to actuation duration uncertainty D1 of starter motor 3 , disengagement duration uncertainty D2 of engagement relay 6 and uncertainty D3 of rotational speed prediction of internal combustion engine 2 .

The respective time sequence basically includes the switch-on instant t1 and the switch-off instant t3 of the starter motor 3 and the switch-on instant t2 of the engagement relay 6 . Here, individually and independently of each other, starter motor 3 is supplied with power by means of power switch 15 and engagement relay 6 is supplied by means of power switch 14 via battery 13 .

Furthermore, for the prediction, it was determined that at the predicted coupling time t4 the rotational speed n2 of the gear wheel 8 should, for example, be approximately 100 revolutions per minute and the rotational speed n1 of the starter gear 7 should be increased by a certain rotational speed difference in order to ensure a reliable meshing, and when the internal combustion engine 2 is idling, the reduction in the rotational speed n2 of the gear wheel 8 is also increased.

FIGS. 3 and 4 show a specific temporal method sequence along the time axis t of a first operating variant according to which the starter motor 3 and the coupling device 4 are triggered overlapping in time. In this case, FIG. 3 schematically shows the triggering of the starter motor 3 and the engagement relay 6 , a distinction being made on the y-axis between the ON and OFF states I. FIG. FIG. 4 shows the rotational speed n1 of the starter gear 7 , the rotational speed n2 of the gear wheel 8 and the power supply R of the engagement relay 6 at time t on the y-axis.

At switch-on time t1 , starter motor 3 is activated in order to start it. Engagement relay 6 is actuated at switch-on time t2 before expiry of the cranking time, in order to move starter gear 7 towards gear wheel 8 . In this case, the starter motor 3 and the coupling device 4 are activated at least temporarily in parallel/simultaneously with each other, ie between the switching-on instant t2 and the switching-off instant t3 . As a result, the time sequence for engagement is shortened and a rapid restart of internal combustion engine 2 is achieved.

The disconnection time t3 is determined such that at the predicted coupling time t4 the peripheral speed with the rotational speed n1 of the starter gear 7 is substantially synchronized with the peripheral speed with the rotational speed n2 of the gear ring 8 . Here, the above-mentioned speed difference is taken into account, and the rotational speed n1 of the starter gear 7 decreases from the disconnection time t3 onwards.

After the disconnection time t3, the power supply to the coupling device 4 continues, so that the starter gear 7, which rotates substantially synchronously with the gear ring 8, moves towards the gear ring 8 and finally comes into contact with it from the coupling time t4. The push-out period can be increased due to the parallel triggering of the starter motor 3 , ie by the voltage fluctuations due to the switch-on and operating currents. Starting at the engagement time t4, the starter gear 7 can be engaged in the gear ring 8 in order to start the internal combustion engine, if necessary, at a later point in time corresponding to the start-stop operation.

FIGS. 5 and 6 show a specific time sequence along the time axis t of another preferred alternative method according to which starter motor 3 and coupling device 4 are activated sequentially in time according to a second operating variant. In this case, FIG. 5 schematically shows the triggering of starter motor 3 and engagement relay 6 with on and off states I on the y-axis. FIG. 6 shows the rotational speed n1 of the starter gear 7 , the rotational speed n2 of the gear wheel 8 and the power supply R of the engagement relay 6 over the time period t on the y-axis.

This method example differs from the example shown in FIGS. 3 and 4 essentially in that the switch-off instant t3 of the starter motor 3 is arranged at a time interval before the switch-on instant t2 of the engagement relay 6 . Thus, the previously mentioned interaction between the starter motor 3 and the engagement relay 6 can be prevented and the known dynamics of the engagement relay 6 obtained in order to reproducibly achieve the push-out duration so that the predicted engagement moment t4 corresponds to This method is more precise than the method according to the first operating variant.

The instants t3 and t4, ie the start-up duration and the push-out duration, are separated in time by a certain pause duration p. The time sequence can thus be flexibly adapted to different variable start-up and/or release durations with the controller 5 by means of a pure adaptation of the pause duration p without significant, in particular switching-technical outlay. The times are adapted in order to reliably achieve the desired coupling instant t4 taking into account the cranking duration uncertainty D1 , the run-off duration uncertainty D2 and the rotational speed prediction uncertainty D3 . During idling of internal combustion engine 2 , the shortening or lengthening of the start-up period of starter motor 3 or the different profiles of rotational speed n2 can be easily considered by adapting pause time p. Taking account of the aforementioned uncertainties D1 , D2 and D3 , the switch-on and switch-off times of the starter motor 3 and the clutch relay 6 are inversely calculated from the calculated predicted engagement time t4 .

During the time sequence between t3 and t4 at least another prediction and correction of the time sequence of the connection point t4 can be carried out, preferably the pause duration p. Short-term disturbing influences that could lead to undesirably high values of the rotational speed difference at the coupling instant t4 are thus easily and reliably counteracted. In particular, it is also possible to compensate for different, for example temperature- or wear-dependent, start-up times.

According to a further method, the accuracy in predicting the connection time t4 is increased by taking into account the switching delay when triggering, for example by evaluating the actual switch-on time t1 and adapting the switch-off time t3 and the possible gap duration accordingly. All figures are only schematic and not to scale representations. Furthermore, in particular reference is made to the drawn illustrations which are relevant to the invention.

Claims (10)

1. Method for operating a controller (5) of a starting device (1) of an internal combustion engine (2), wherein the starting device (1) comprises an electric motor (3), in particular a starter motor (3) and a coupling device ( 4), and the coupling device (4) has in particular a starter gear (7) for meshing into the gear ring (8) of the internal combustion engine (2), wherein the electric motor (3) and the said coupling device (4), and said electric machine (3) is coupled with a rotating, in particular idling, internal combustion engine (2), characterized in that said electric machine (3) and said The time sequence of the triggering of the coupling device (4) is described. 2. The method according to claim 1, characterized in that the speed of rotation and/or the inertia gradient of the internal combustion engine (2) are taken into account by the operating concept. 3. The method according to claim 1 or 2, characterized in that a future connection moment (t4) is predicted and the time course is determined taking into account the prediction of the connection moment (t4), in particular wherein The time course is matched based on at least one other prediction. 4. The method according to any one of claims 1 to 3, characterized in that the electric motor (3) is activated temporally before the coupling device (4) is activated. 5. The method according to any one of claims 1 to 4, characterized in that the electric motor (3) and the coupling device (4) are actuated overlappingly in time according to a first operating variant in the time method sequence ). 6. The method according to any one of claims 1 to 5, characterized in that the motor (3) and the coupling device ( 4), more precisely, in particular with a defined pause duration (p) between the activation of the electric motor ( 3 ) and the activation of the coupling device ( 4 ). 7. The method according to any one of claims 1 to 6, characterized in that the detection triggers the actual switch-on moment (t1) of the motor (3) and based on the actual switch-on moment (t3) Make the moment of disconnection (t3) match it. 8. A controller (5) for a starting device (1) of an internal combustion engine (2), wherein the starting device (1) comprises an electric motor (3), in particular a starter motor (3) and a coupling device (4), And the coupling device has in particular a starter gear (7) for meshing into the gear ring (8) of the internal combustion engine (2), the electric motor (3) can be activated individually by means of the controller (5) and said coupling device (4), and said electric machine (3) can be coupled with a rotating, especially idling running internal combustion engine (2), characterized in that said controller (5) is designed with a selectable operating program to determine a specific time sequence for triggering the electric motor (3) and the coupling device (4), and subsequently more precisely in particular a method according to any one of claims 1 to 7 to trigger. 9. Starting device (1) for an internal combustion engine (2), wherein the starting device (1) has an electric motor (3), in particular a starter motor (3), a coupling device (4) and in particular according to claim 8 The controller (5), the coupling device in particular having a starter gear (7) for meshing into the gear ring (8) of the internal combustion engine (2), is capable of individually activating the electric motor (3) and the coupling device (4), and the electric machine (3) can be coupled with a rotating, in particular idling, internal combustion engine (2), characterized in that the starting device (1) is designed in such a way that according to the operating scheme More precisely, in particular, the method according to any one of claims 1 to 7 can determine and carry out a specific time sequence for triggering the electric motor ( 3 ) and the coupling device ( 4 ). 10. Computer program product which can be loaded into a program memory (10) with program instructions of a microcomputer (9) in order to carry out all steps of the method according to at least one of claims 1 to 7, in particular when When executing the computer program product in a controller (5) according to claim 8 or in a starting device (1) according to claim 9.

Images