WO2017016560A1

WO2017016560A1 - Method and device for controlling restarting of an internal combustion engine of a vehicle when exiting a coasting mode

Info

Publication number: WO2017016560A1
Application number: PCT/DE2016/200331
Authority: WO
Inventors: Markus Kneissler; Matthias Baumann
Original assignee: Schaeffler Technologies AG & Co. KG
Priority date: 2015-07-30
Filing date: 2016-07-21
Publication date: 2017-02-02
Also published as: CN107787404A; DE102015214551A1; JP2018523056A; DE112016003439A5

Abstract

The invention relates to a method for controlling restarting of an internal combustion engine when a vehicle which is embodied with a transmission exits the coasting mode in which the clutch is automatically opened and closed again while the vehicle is travelling. In the method, it is decided as a function of the current driving state of the vehicle whether the restarting of the internal combustion engine is carried out by push starting or towed starting by closing the clutch or by means of a starter unit.

Description

METHOD AND DEVICE FOR CONTROLLING A RECURRENCE OF ONE

COMBUSTION ENGINE OF A VEHICLE WHEN EMITTING FROM A SAILING OPERATION

The invention relates to a method for controlling a restart of an internal combustion engine at an outlet of a trained with a manual transmission vehicle from a sailing operation, and an apparatus for performing the method.

From DE 102 21 701 A1 a control method for vehicles with an automated clutch device is known in which the vehicle is put into a sailing mode. Sailing is a purposeful disengagement in slippage phases in which neither the accelerator pedal as a fuel feed control member nor the brake pedal are actuated. This sailing mode essentially serves to save fuel. In this case, the vehicle rolls, wherein the vehicle driving the engine is either off or running at an idle speed. In the sailing mode, the clutch is opened under control by the electronic control unit when the gear is engaged, so that the vehicle rolls without losing kinetic energy due to the braking effect of the engine. The sailing mode is terminated by pressing a brake or the accelerator pedal. The engine must be restarted, which is done by hauling the engine to a starting speed

As is known from EP 1 497 151 B2, the internal combustion engine can also be started by means of a starter unit.

The disadvantage here is that for the exit from the sail always a constant strategy for restarting the engine is selected, which does not change during operation of the vehicle.

The invention has for its object to provide a method for controlling a restart of an internal combustion engine at an outlet of a trained with a manual transmission vehicle from a sailing operation, in which the disadvantages of the prior art can be improved. According to the invention the object is achieved in that it is decided in dependence on a current driving condition of the vehicle, whether the restart of the Ver combustion engine by a swing or towing start by closing the clutch or by a starter unit. This has the advantage that it can be decided as a function of the driving state whether a start of the internal combustion engine should take place by means of a starter or a fly or towing start of the internal combustion engine. In this case, a parameter range of different parameters of the vehicle, which is set variably within parameter limits, is to be understood below as the current driving state. The parameter limits, which are considered in the current vehicle state, give conclusions about the driving situation and can be detected on the basis of eg an accelerator pedal position, a brake pedal position or a steering angle.

Advantageously, a decision is made as a function of at least one vehicle-specific parameter as to whether the restart of the internal combustion engine takes place by means of a fly or towing start by closing the clutch or by a starter unit. Such a vehicle-specific parameter can be understood, for example, as the battery state of charge or an engine speed.

In one embodiment, the restart of the internal combustion engine takes place as a function of a vehicle acceleration. From this, it is particularly easy to deduce whether the engine requires a starter, whether it should start a sweep or whether it should be towed - e.g. When the vehicle is decelerating when the overrun mode is desired, the internal combustion engine can be coupled by the clutch without injection.

In one variant, the fly or towing start takes place when the vehicle acceleration exceeds a threshold value. Alternatively, the starter unit is activated when the vehicle acceleration falls below the threshold value. Thus, the restart during the sail exit can be made variable. A decision between the fly and towing start and the starter start is made only after the decision on the sail exit.

A refinement of the invention relates to a device for controlling a restart of an internal combustion engine when a vehicle equipped with a manual transmission exits a sailing operation, which activates a clutch arranged in the transmission for opening and closing while the vehicle is traveling. In one device, an engine start logic unit is provided with at least one first sensor unit for outputting a vehicle-specific parameter. and a second sensor unit connected to display a current driving condition of the vehicle, which is guided to a clutch control unit and a starter control unit for restarting the engine. This makes it possible to vary the engine restart depending on the vehicle situation. Advantageously, the engine start logic unit is superior to a sail end logic unit. Due to this superordination, the engine start logic unit is only active when the end of sail logic unit has informed by a signal that an exit from the sailing operation is to be made.

The invention allows numerous embodiments. One of them will be explained in more detail with reference to the figures shown in the drawing.

Show it:

1 shows an embodiment of the device according to the invention,

Fig. 2 shows an embodiment of the method according to the invention.

In Fig. 1, a control unit 1 is shown, which represents an embodiment of the inventive device. The control unit 1 is designed as an engine control unit, but may alternatively be a separate control unit which controls a sailing operation in a vehicle with a manual transmission. The vehicle with manual transmission thereby has a clutch actuator, which can optionally open the clutch parallel to the clutch pedal or has the sole control of the clutch operation. The clutch actuator can receive signals via one or more sensors which detect the position of the clutch pedal on the pedal itself or on the master cylinder of the disengagement system or otherwise detect the intention of the driver to actuate the clutch by means of the clutch pedal. The term sailing should be understood hereinafter in the automatic opening of the clutch, in particular during the journey of the vehicle, with the additional option is to turn off the engine in these sailing phases. The aim of the blessing is to decouple the internal combustion engine from the drive train in order to avoid its drag torque as loss torque, which can lead to fuel savings. The control strategy stored in the control unit 1 globally regulates the opening and closing of the clutch independently of the driver's operation as well as the switching off or on of an internal combustion engine driving the vehicle.

The control unit 1 comprises four logic units 2, 3, 4, 5. The first logic unit 2 is a sail start logic unit 2, which is connected to a motor logic unit 3. Parallel to the sail start logic unit 3, a sail end logic unit 4 is present, which decides on the shutdown of the sail operation. This end of sail logic unit 4 leads to an engine start logic unit 5, which is connected to a clutch control unit 6 for closing the clutch for restarting the internal combustion engine and to a starter unit 7 for starting the internal combustion engine. All four logic units 2, 3, 4, 5 are independently the same input signals available by each logic unit 2, 3, 4, 5 directly with a first sensor unit 8 for outputting a vehicle-specific parameter and with a second sensor unit 9 for displaying the driving condition of Vehicle is connected. An embodiment of the method according to the invention is shown in FIG. In this case, the input signals of the first sensor unit 8 are provided in block 101, which are characterized by the vehicle-specific parameters. In parallel, in block 102, further input signals of the second sensor unit 9 are provided, which characterize the vehicle condition. These input signals are once passed to block 103, where the input signals are evaluated and decided on the sail entry. This is followed by the block 104, which triggers the sail entry of the vehicle.

When triggered sailing operation is passed to block 105, at which also the input signals of the blocks 101 and 102 are evaluated directly. In block 105 it is decided which state the internal combustion engine of the vehicle should have during sailing operation. There are three different states. In block 106, the internal combustion engine is operated during the entire sailing operation while it remains off in block 107 during the entire sailing operation. In block 108, a restart of the internal combustion engine is possible after switching off this during sailing operation.

At the same time, the input signals 101 and 102 lead at a block 109, which decides in dependence on these input signals whether the sailing operation is ended. If the decision is made that the sailing operation is terminated, takes place in block 1 10 the end of the sailing operation. If the end of the sailing operation is initiated, the block 1 1 1 is passed, which decides based on the also directly applied to it input signals 101 and 102, as a restart of the engine should be performed when it is not in operation at the exit from the sailing operation. Advantageously, this decision is made based on an acceleration of the internal combustion engine. This acceleration is compared with an acceleration threshold. If the acceleration is greater than the acceleration threshold value, a drag start of the internal combustion engine is initiated by the closing of the clutch (block 1 12). If the acceleration of the vehicle is less than the acceleration threshold value, then a signal is output to the starter unit 7, which serves as a starting aid for the internal combustion engine (block 1 13).

Reference numerals control unit

Start sailing logic unit

Motor-logic unit

Sailing end logic unit

Engine start logic unit

Clutch control unit

starter unit

sensor unit

Claims

claims

1 . A method for controlling a restart of an internal combustion engine at an exit of a trained with a manual transmission vehicle from a sailing operation in which a clutch is automatically opened and closed during a journey of the vehicle, characterized in that is decided in dependence on a current driving condition of the vehicle whether the restart of the internal combustion engine is carried out by a fly or towing start by closing the clutch or by a starter unit.

2. The method according to claim 1, characterized in that it is decided as a function of at least one vehicle-specific parameter, whether the restart of the internal combustion engine by a fly or towing start by closing the clutch or by a starter unit.

3. The method according to claim 1, characterized in that the restart of the internal combustion engine takes place as a function of vehicle acceleration.

4. The method according to claim 1, 2 or 3, characterized in that the

Fly or towing start takes place when the vehicle acceleration exceeds a threshold value.

5. The method of claim 1, 2 or 3, characterized in that the starter unit is activated when the vehicle acceleration is below the threshold.

6. A device for controlling a restart of an internal combustion engine at an outlet of a vehicle equipped with a manual transmission vehicle from a sailing operation, which controls a, arranged in the transmission clutch for opening and closing while driving the vehicle, characterized in that an engine start logic unit ( 5) is connected to at least a first sensor unit (8) for outputting a vehicle-specific parameter and a second sensor unit (9) for displaying a current driving condition of the vehicle, which to a clutch control unit (6) and a starter control unit (7) for restarting the internal combustion engine is guided.

7. The device according to claim 6, characterized in that the engine start logic unit (5) is superordinate a sail end logic unit (4).