WO2014057453A1

WO2014057453A1 - Automatic stop and start system for a motor vehicle internal combustion engine with signalling of imminent automatic internal combustion engine restarting not resulting from a motor vehicle driver' s request

Info

Publication number: WO2014057453A1
Application number: PCT/IB2013/059269
Authority: WO
Inventors: Antonio Piccinini; Renato Zenzon
Original assignee: Fiat Group Automobiles S.P.A.
Priority date: 2012-10-10
Filing date: 2013-10-10
Publication date: 2014-04-17
Also published as: ITTO20120884A1

Abstract

An automotive electronic control system (E-ECU, PWT-ECU; ECU) for a powertrain (PWT) of a motor vehicle (MV); the powertrain (PWT) comprising an internal combustion engine (ICE) and a transmission line (T) comprising a gearbox (G) and a clutch (C); and the automotive electronic control system (ECU being configured to receive quantities indicative of the operating conditions of the motor vehicle (MV), the powertrain (PWT) and other on-board systems/components of the motor vehicle (MV) and to cause automatic stopping of the internal combustion engine (ICE) upon detection of the occurrence of certain operating conditions of the motor vehicle (MV) and/or the powertrain (PWT) and/or on-board systems/components of the motor vehicle (MV), and cause automatic restarting of the internal combustion engine (ICE) upon detection of an action performed by the driver indicative of his/her wish to restart the internal combustion engine (ICE) or upon detection of the occurrence of at least one of a plurality of certain operating conditions of the motor vehicle (MV) and/or the powertrain ( PWT) and/or on-board systems/components of the motor vehicle (MV) that are considered to be such as to require automatic restarting of the internal combustion engine (ICE). The automotive electronic control system (ECU) is further configured to trigger the signalling of the imminent restarting of the internal combustion engine (ICE) upon detection of the occurrence of an operating condition of the motor vehicle (MV) and/or the powertrain (PWT) and/or on-board systems/components of the motor vehicle (MV) that is considered to be such as to require automatic starting of the internal combustion engine (ICE) and different from the driver taking action indicative of his/her wish to restart the internal combustion engine (ICE), and prior to the consequent automatic restarting of the internal combustion engine (ICE).

Description

AUTOMATIC STOP AND START SYSTEM FOR A MOTOR VEHICLE INTERNAL COMBUSTION ENGINE WITH SIGNALLING OF IMMINENT AUTOMATIC INTERNAL COMBUSTION ENGINE RESTARTING NOT RESULTING FROM A MOTOR VEHICLE DRIVER' S REQUEST

TECHNICAL FIELD OF INVENTION

The present invention refers in general to the operational management of an automatic stop and start system for an internal combustion engine of a motor vehicle and, in particular, to the signalling of imminent automatic restarting of the internal combustion engine not resulting from a motor vehicle driver's request.

STATE OF THE ART

In order to reduce the fuel consumption and pollutant emissions of motor vehicles, car manufacturers are progressively introducing so-called Stop&Start systems on - motor vehicles for automatically stopping and starting the internal combustion engine when certain operating conditions on the motor vehicle, the powertrain and/or on-board systems/components occur that are considered not impedimental to- stopping the internal combustion, engine (ICE) and, respectively, that are instead considered impedimental to keeping the internal combustion engine switched off.

In _. particular, Stop&Start systems are configured to automatically stop the internal combustion engine when the motor vehicle is about to stop, in particular when its speed drops below a minimum speed, currently between zero and 10 km/h, depending on the manufacturer, traction power is not requested, in particular the accelerator pedal is not pressed and the gearbox is in neutral, in the case where the gearbox is manual, or in ^rive' , in the case where the gearbox is automatic or similar, and the operating conditions of some onboard systems /components of the motor vehicle are not considered impedimental to switching off the internal combustion engine, for example, the battery is well charged. - -

Stop&Start systems are also configured to cause the restarting of the internal combustion engine when the driver of the motor vehicle takes action indicative of his/her wish to restart the internal combustion engine, for example, operating the clutch pedal to engage a gear, or the occurrence of any of a series of certain operating conditions of the motor vehicle, the powertrain and/or on-board systems/components of the motor vehicle that are such as to render restarting the internal combustion engine advisable, or even necessary; in the example considered, this a progressive deterioration in the battery's state of charge when the internal combustion engine is switched off.

Stop&Start systems have also -been proposed with informative capabilities regarding the automatic stopping and starting of the internal combustion engine.

For example, FR 2 955 072 describes an automatic stop and start system for an internal combustion engine capable of discriminating whether or not the automatic restart of the internal combustion engine has taken place in response to a request from the driver and, in the case where the automatic restart of the internal combustion engine is not due to a request from the driver, informing the driver if this automatic restart corresponds to normal operation or whether it is due to an error of the stop and start system of the internal combustion engine.

EP 1 612 408 describes an automatic stop and start system for an internal combustion engine the operation of which is indicated via the instrument panel of the motor vehicle, which is equipped with an automatic stop indicator light that is lit for the entire period in which the internal combustion engine is automatically switched off, so as to inform the driver that the internal combustion engine is in an automatic stop state, and an automatic restart indicator light that is temporarily lit only when the internal combustion engine is automatically restarted, so as to inform the driver that the internal combustion engine is in the automatic restart phase. - -

SUBJECT AND ABSTRACT OF THE INVENTION

The Applicant has carried out an analysis of the informative capabilities of known stop and start systems for automatic internal combustion engines with the aim of evaluating the informative performance and has noted the presence of informative deficits such as to cause incomplete or erroneous perception of the operation of these automatic internal combustion engine stop and start systems.

The object of the present invention is therefore to provide a solution that at least partially remedies the informative deficits of the automatic internal combustion engine stop and start systems identified by the applicant.

This object is achieved by the present invention in so far as it relates to an automotive electronic control system, as defined in the appended claims.

BRIEF DESCRIPTION OF DRAWINGS

The attached figure is a block diagram of an automotive powertrain .

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS OF THE INVENTION

The present invention will now be described in detail with reference to the attached figure, to enable an expert in the field to embody it and use it. Various modifications to_. the described embodiments will be immediately obvious to experts in the field, and the generic principles described herein can be applied to other embodiments and applications without departing from the scope of the present invention, as defined in the appended claims. Thus, the present invention is not intended to be limited to the embodiments set forth herein, but is to be accorded the widest scope consistent with the principles and features disclosed and claimed herein.

Figure 1 shows, by way of non-limitative example, a block diagram of a powertrain PWT of a motor vehicle MV. The powertrain PWT comprises an internal combustion engine ICE, the crankshaft CS of which is coupled to a servo-actuated - - transmission line T.

The transmission line T can indifferently be of the single-clutch type, as shown in Figure 1, or of the dual- clutch type (not shown) .

In the case where a single-clutch transmission line T is used, as shown in Figure 1, the transmission line T comprises a discrete-ratio gearbox G, of the type with gears, with an input shaft I that can be connected to the crankshaft CS by a single clutch C external to the gearbox G, and an output shaft 0 that can be connected to a pair of driven wheels W through a differential D of known type.

The clutch C is servo controlled by means of an associated electrically or electrohydraulically controlled actuator CA. The gearbox G is also servo controlled by means of a plurality of electrically or electrohydraulically controlled actuators, indicated as a whole by GA, which can be controlled to engage or disengage the gears corresponding to the different gear ratios that can be obtained.

In the case where a dual-clutch transmission line T is used, instead of a single-plate clutch C external to the gearbox G, the transmission line T comprises two distinct clutches (not shown) integrate inside the gearbox G, one associated with the even gears and the other associated with the odd gears.

The internal combustion engine ICE is also connected to an alternator A by a transmission assembly comprising a transmission belt B and a plurality of pulleys P.

The internal combustion engine ICE and the alternator A are controlled by a first electronic control unit E-ECU which is in itself known and therefore not described in detail, while the remaining part of the powertrain PWT is controlled by a second electronic control unit PWT-ECU connected to the first electronic control unit E-ECU through an automotive onboard communication network NET, for example, CAN, FlexRay or others, as well as to the actuators CA and GA associated with the clutch C and the gearbox G. Through the same on-board communications network NET, - the second electronic control unit PWT-ECU is also connected to a body computer BC programmed to receive, through the on-board communications network NET, quantities indicative of the operating conditions of on-board systems/components of the motor vehicle MV, such as the powertrain PWT, battery/batteries, accelerator pedal AP, brake pedal, handbrake, etc., and to consequently manage operations.

In a different embodiment that is not shown, the first electronic control unit E-ECU of the internal combustion engine ICE and the -second electronic control unit PWT-ECU of the powertrain PWT are integrated in single electronic control unit ECU that performs the functions of the first and second electronic control units E-ECU and PWT-ECU.

Operation of the transmission line T is controlled by the second electronic control unit PWT-ECU on the basis of the position of a selector SL, typically made in the form of a selection lever, connected to the second electronic control unit PWT-ECU and operable by the driver to take different operating positions which correspond to different operating modes of the transmission line T, typically comprising:

an . automatic mode, in which the gears are changed automatically by the electronic control unit; and

• a semi-automatic mode, in which the driver controls the sequential changing of gears by means of the selector SL or specific sequential gear-change means (not shown) , for example installed of the steering wheel (not shown) .

In an alternative embodiment that is not shown, the transmission line T could be of the manually controlled type, in which the powertrain PWR is devoid of the actuators CA and GA associated with the clutch C and the gearbox G, respectively, and the clutch C is operated directly by the driver using the clutch pedal (not shown) , just as the gearbox G is operated directly by the driver using the gearbox lever (not .shown) . Furthermore, in this type of transmission line T, the powertrain PWR is also devoid of the second electronic control unit PWT-ECU, the functions of which, described below - - with regard to the implementation of an automatic stop and start system for the internal combustion engine ICE, are implemented by the first electronic control unit E-ECU or by a different electronic control unit on board the motor vehicle MV.

Again with reference to the embodiment shown in Figure 1, the body computer BC and the electronic control unit E-ECU or ECU are programmed to implement automatic stop and start functionality for the internal combustion engine, which comprises:

• causing automatic stopping of the internal combustion engine ICE upon detection of the occurrence of certain operating conditions of the motor vehicle MV and/or the powertrain PWT and/or on-board systems/components of the motor vehicle MV that are considered as enabling the automatic stopping of the internal combustion engine ICE, for example, the current speed of the motor vehicle MV is close to zero, the gearbox G has been put in neutral, in the case of a manually controlled transmission line T, or, in the case of a servo-actuated transmission line T, this has been disengaged, the states of electrical charge and functional integrity of the battery/batteries are above predetermined thresholds, the outside air temperature is above a predetermined temperature threshold, for example 3 °C, the air conditioning system is switched off, specific on-board systems /components , in particular safety-critical ones, do not indicate any failures or faults, etc.; and

• causing automatic restarting of the internal combustion engine ICE upon detection of an action performed by the driver indicative of his/her wish to restart the internal combustion engine ICE, for example operation of the clutch pedal, in the case of a manually controlled transmission line T, or the operation of the accelerator pedal or the selector SL, in the case of a servo-actuated transmission line T, or upon detection of the occurrence of at least one of a plurality of operating conditions of the motor vehicle MV and/or the - - powertrain PWT and/or on-board systems/components of the motor vehicle MV considered to be such as to require, in the sense of making it advisable, or even necessitate, automatic restarting of the internal combustion engine ICE, for example, the states of electrical charge and functional integrity of the battery/batteries are below predetermined thresholds, the outside air temperature drops below a predetermined temperature threshold, for example 3 °C, the air conditioning system is on, specific on-board systems/components, for example safety-critical ones, indicate neither failures nor faults, etc.

It should be noted that for the purposes of the present invention, it is not important which of the functions described hereinafter are specifically implemented by the body computer BC and which are instead implemented by the electronic control unit E-ECU or ECU, but rather only what functions are implemented, to the point where they could even all be implemented by one or the other of the two, according to the software architecture, that the manufacturer of the motor vehicle MV considers convenient to implement. Thus, for this reason, and also for ease of description, hereinafter the description will make reference to the functions performed by the automatic stop and start management software for the internal combustion engine ICE in generic terms, without specifying whether these functions are specifically implemented by software loaded in the body computer BC and/or by that loaded in the electronic control unit E-ECU or ECU.

In particular, the automatic stop and start management software for the internal combustion engine ICE is designed so as to ensure that the body computer BC and the electronic control unit E-ECU or ECU can decide independently on the automatic stopping and starting of the internal combustion engine ICE, subject to checking that there is no impediment in that sense.

By way of non-limitative example, automatic restarting of the internal combustion engine ICE linked to the state of charge of the battery/batteries can be conveniently controlled by the electronic control unit E-ECU or ECU upon request from the body computer BC, as it is the latter that is set up to check the state of charge of the battery/batteries., subject to the. electronic control unit E-ECU or ECU checking that the necessary safety conditions for the motor vehicle exist (for example, the gearbox is in neutral) .

Automatic restarting of the internal combustion engine ICE that is instead linked to a timeout on the stopping of the internal combustion engine ICE expiring or in response to an action performed by the driver of the motor vehicle indicative of his/her wish to restart the internal combustion engine ICE and determined on the basis of information acquired directly or through the on-board communications network NET, can be conveniently and independently controlled by the electronic control unit E-ECU or ECU, subject to the electronic control unit E-ECU or ECU checking that no impediments signalled by- the body computer BC exist that prevent automatic restarting.

To cause the automatic stopping and starting of the internal combustion engine ICE, automatic stop and start management software for the internal combustion engine ICE is designed to determine, on the basis of input signals received by the body computer BC and/or the electronic control unit E- ECU or ECU, if the above-mentioned conditions exist to proceed in this sense, and to ensure that the first and second electronic control units PWT-ECU and E-ECU or electronic control unit ECU cause the automatic stopping and starting of the ^internal combustion engine ICE, as well as, in the case of a servo-actuated transmission line T, the disengagement and engagement of the latter by opportune operation of the actuator CA associated with the clutch C.

Furthermore, the automatic stop and start management software for the internal combustion engine ICE is designed to ensure that the active/disabled operating state of the automatic stop and start function for the internal combustion engine ICE is signalled to the driver of the motor vehicle MV. -

Typically, this signal is of the visually perceptible type and is effected by opportunely controlling the instrument panel of the motor vehicle MV so that a specially provided icon is displayed or not, or by opportunely controlling a specially provided backlightable indicator fitted_' on the dashboard.

Furthermore, according to the present invention, in the case where automatic restarting of the internal combustion engine ICE is caused by detecting the occurrence of an operating condition of the motor vehicle MV and/or the powertrain PWT and/or on-board systems/components of the motor vehicle MV that is considered such as to require the automatic starting of the internal combustion engine ICE and different from the driver taking action indicative of his/her wish to restart the internal combustion engine ICE, the automatic stop and start management software for the internal combustion engine ICE is designed to trigger, prior to the consequent automatic restarting of the internal combustion engine ICE, the signalling of the imminent automatic restarting of the internal combustion engine ICE.

This signalling thus avoids the driver, as well as the other occupants of the motor vehicle MV, being taken by surprise by unexpected automatic restarting internal combustion engine ICE not due to the driver's will, or rather not due to the driver taking action indicative of his/her wish to restart the internal combustion engine ICE, in order to resume driving the motor vehicle MV. This signalling, as well as being an indication of the correct operation of the automatic stop and start function of the internal combustion engine ICE, corrects one of the deficiencies identified by the applicant of the informative capabilities of known automatic internal combustion engine stop and start systems, consequently improving the perception the driver has of the correct operation of the automatic stop and start function of the internal combustion engine ICE.

This signalling can be performed by controlling a signalling device of the motor vehicle MV capable of providing - -

a visual and/or sound and/or haptic signal.

In particular, a visual signal can conveniently be implemented by using and opportunely controlling the same icon or the same backlightable indicator used to indicate the active/disabled operating state of the automatic stop and start function for the internal combustion engine, or by using and opportunely controlling an icon or a backlightable indicator specially provided for this purpose.

Whereas a sound signal can, for example, be implemented by using and opportunely controlling a specially provided audible warning device provided in the interior of the motor vehicle MV or by using the speaker system of the car radio of the motor vehicle MV.

Lastly, a haptic signal can, for example, be implemented by using and opportunely controlling a specially provided actuator capable of producing vibrations on an element placed in contact with the driver, for example, the steering wheel, seat, or gearbox lever.

Furthermore, for the purpose of improving the perception the driver and the other occupants of the motor vehicle MV have of the imminent restarting of the internal combustion engine ICE, the body computer BC is further programmed to opportunely act on the on-board systems of the motor vehicle MV, for example, on the car radio to opportunely reduce the volume to a level that makes the sound signal more audibly perceptible.

Claims

1. An automotive electronic control system (E-ECU, PWT- ECU, BC; ECU, BC) for a powertrain (PWT) of a motor vehicle (MV) ; the powertrain (PWT) comprising an internal combustion engine (ICE) and a transmission line (T) comprising a gearbox (G) and a clutch (C) ; and the automotive electronic control system (ECU) being configured to receive quantities indicative of the operating conditions of the motor vehicle (MV) , the powertrain (PWT) and other on-board systems/components of the motor vehicle (MV) and to:

• cause automatic stopping of the internal combustion engine (ICE) upon detection of the occurrence of certain operating conditions of the motor vehicle (MV) and/or the powertrain (PWT) and/or on-board systems/components of the motor vehicle (MV) , and

• cause automatic restarting of the internal combustion engine (ICE) upon detection of an action performed by the driver indicative of his/her wish to restart the internal combustion engine (ICE) or upon detection of the occurrence of at least one of a plurality of certain operating conditions of the motor vehicle (MV) and/or the powertrain (PWT) and/or onboard systems/components of the motor vehicle (MV) considered to be such as to require automatic restarting of the internal combustion engine (ICE);

the automotive electronic control system being characterized in that it is further configured to:

• upon detection of the occurrence of an operating condition of the motor vehicle (MV) and/or the powertrain (PWT) and/or on-board systems/components of the motor vehicle (MV) that is considered to be such as to require automatic starting of the internal combustion engine (ICE) and different from the driver taking action indicative of his/her wish to restart the internal combustion engine (ICE) , and prior to the consequent automatic restarting of the internal combustion engine (ICE), trigger the signalling of the imminent restarting of the internal combustion engine (ICE).

2. An automotive electronic control system according to claim 1, further configured to operate a signalling device of the motor vehicle ( V) provided to supply a visual and/or sound and/or haptic signal.

3. An automotive electronic control system according to claim 1, further configured to control on-board systems of the motor vehicle (MV) so as to improve perception of the signalling of the · imminent restarting of the internal combustion engine (ICE) .

4. An automotive electronic control system according to claim 3, wherein the on-board systems of the motor vehicle (MV) comprise a car radio, and wherein the automotive electronic control system is further configured to reduce the volume of the car radio so as to improve ^* the auditory •perception of the sound signal for the imminent restarting of the internal combustion engine (ICE) .

5. An automotive electronic control system according to any of the preceding claims, comprising an electronic control unit (E-ECU) for the internal combustion engine (ICE) , an electronic control unit (PWT-ECU) for the powertrain (PWT) and a body computer (BC) connected to one another through an automotive on-board communication^" network (NET), and wherein the electronic control units (E-ECU, PWT-ECU) and the body computer (BC) are programmed to cause the automotive electronic control system (ECU) to become configured as claimed in any one of the preceding claims.

6·. An automotive electronic control system according to any one of claims 1 to 4, comprising a single electronic control unit (ECU) for both the internal combustion engine (ICE) and the powertrain (PWT) and a body computer (BC) connected to the electronic control unit (ECU) through an automotive on-board communication network (NET) , and wherein the electronic control unit (ECU) and the body computer (BC) are programmed to cause the automotive electronic control system (ECU) to become configured as claimed in any one of the preceding claims.

7. A motor vehicle (MV) comprising a powertrain (PWT) comprising an internal combustion engine (ICE) ; a transmission, line (T) comprising a gearbox (G) and a clutch (C) ; and an electronic control system (E-ECU, PWT-ECU, BC; ECU, BC) as claimed in any one of claims 1 to 6.

8. Software 'loadable in an automotive electronic control system (E-ECU, PWT-ECU, BC; .ECU, BC) and designed to cause, when executed, the automotive electronic control system (ECU) to become configured as claimed in any one of claims 1 to 4.