Control system for automatically activating or deactivating a roll-away protection device in motor vehicles

Abstract

Control system for automatically activating or deactivating a roll-away protection system (AUTO-P) in motor vehicles, comprising at least one electronic control unit which is designed in such a way that limited maneuvering operation (RB; RB_e) is possible within defined boundary conditions in accordance with predetermined entry conditions and in accordance with predetermined exit conditions (AK), wherein a predetermined entry condition is defined as a conscious desire of the driver to maneuver after the vehicle has previously been automatically secured (AUTO-P), characterized in that a predetermined exit condition (AK) is the vehicle starting off and exceeding a speed threshold, after which the roll-away protection system (AUTO-P) is activated again when the vehicle is next stationary, wherein the exit condition (AK) describes a case in which a transition to driving with the door ajar takes place.

Description

[0001] The invention relates to an electronic control system for automatically activating or deactivating a parking lock or a roll-away safety device in motor vehicles.

[0002] For example, an electronic control system or method for automatically activating a parking lock in motor vehicles is already known from DE 100 37 576 A1. In principle, the automatic activation of a parking lock when the key is removed, whereby an electronic authorization verification device is functionally equivalent to a conventional key system, is required by law in some countries. For safety reasons, the parking lock has long been automatically activated even in vehicles without a mechanical key, regardless of the key position, depending on at least one other operating parameter or operating state. In particular, operating parameters or signals are evaluated that indicate that the vehicle has been left behind, such as an unactuated brake and / or accelerator pedal, an open driver's door (e.g., can be interrogated via a switch in the door) and / or an unoccupied driver's seat (e.g.,detectable via seat occupancy sensors or via the opened seat belt buckle). This publication particularly concerns vehicles with electronic access and drive authorization systems which no longer have a mechanical key and therefore can no longer be removed. Such access and drive authorization systems include, for example, transponders or code cards carried by the driver which communicate wirelessly (e.g. via radio) with an authorization verification device installed in the vehicle. In principle, the parking lock should be activated automatically when the internal combustion engine is switched off, preferably by engaging the park position if there is an automatic transmission or by engaging a parking brake. According to the aforementioned publication, it is also possible to arbitrarily prevent automatic activation of the parking lock by means of a manually operated OFF button.

[0003] DE 103 92 606 B4 describes a method for controlling the actuation of an auxiliary transmission of a vehicle. In the auxiliary transmission, a triggering process for deactivating a parking lock can be a sliding movement of a gear position selector.

[0004] Furthermore, DE 10 2006 005 335 A1 describes a control method for a motor vehicle that prevents the motor vehicle from starting from a standstill if at least one door of the motor vehicle is open. When the drive gear is engaged, starting is prevented by preventing the motor vehicle's parking brake from being released or activated. When the drive gear is not engaged, no traction is established between the drive wheels and the motor vehicle's engine.

[0005] DE 10 2007 037 706 A1 discloses an actuating device for selecting gear ratios of a gearshift transmission with a gear selection element. A switching device for selecting the gear ratios of the gearshift transmission is arranged on the gear selection element. The actuating device has an additional parking lock actuating element for activating and deactivating the parking lock.

[0006] Furthermore, EP 2 719 587 A1 describes a method for operating an electrically actuated parking brake system of a vehicle, wherein a transfer of the electrically actuated parking brake system from a released operating state to an applied operating state is initiated and a predetermined waiting time begins when the presence of a triggering event is detected which is independent of an actuating device which is provided for manually actuating the electrically actuated parking brake system and / or for releasing the parking brake system if an actuating device is faulty.

[0007] Finally, DE 10 2010 055 921 A1 discloses a method for automatically activating a parking function of an automatic or automated transmission in a vehicle. The method can be activated below a predeterminable speed threshold, so that the parking lock is automatically activated by the control unit only below a set vehicle speed.

[0008] The invention is based on the object of designing a control system for automatically activating or deactivating a parking lock in motor vehicles in a more customer-oriented manner.

[0009] According to the invention, this object is achieved by the features of the independent claims, while preferred developments of the invention are specified in the dependent claims.

[0010] The term parking lock or automatic anti-roll device is to be understood here in the broadest sense as the so-called "AUTO-P" function; ie an automatic holding or automatic securing of the vehicle against rolling away when defined conditions exist, which in particular indicate that the vehicle is being abandoned (e.g. also in accordance with the state of the art), for example by means of a parking pawl of an automatic transmission and / or by means of a parking brake function of the service brake and / or by means of an electromechanical auxiliary brake or handbrake.

[0011] The invention relates to a control system for a motor vehicle for automatically activating or deactivating a parking lock or an automatic "AUTO-P" anti-rollover system. The control system has at least one electronic control unit such that limited maneuvering is possible within defined boundary conditions according to predefined entry conditions and predefined exit conditions. A predefined entry condition is defined as a recognized, conscious maneuvering request by the driver after the vehicle's automatic "AUTO-P" anti-rollover system has previously been activated. The limited maneuvering can be activated both with the engine running and with the engine off, starting from the secured "AUTO-P" state.Depending on the fulfillment of the differently defined exit conditions, the vehicle can either transition from the limited shunting operation to the secured state “AUTO-P” or drive operation can be permitted if the defined conditions for the automatically secured state “AUTO-P” no longer apply. The invention is based on the following considerations:

[0012] Currently, according to the state of the art, the selector lever position P or the automatic parking lock is automatically engaged in the following situations: - After switching off the engine in radio standby mode or ignition off if selector lever position R or D is engaged. - When the ignition is off and the selector lever is in position N. - When stationary with the selector lever in position D or R, the driver's belt is unfastened, the driver's door is open and the brake is not depressed (=> driver absence detection).

[0013] Driver absence detection prevents or impedes maneuvering. Starting or rolling away without the driver is not permitted. The vehicle is secured against rolling away by disengaging the gear. A deliberate maneuvering request by the driver is not possible with current technology.

[0014] Maneuvering without a seatbelt and with the driver's door open (e.g., when reversing into parking spaces with a curb) in automatic vehicles with shift-by-wire is currently not possible due to functional safety requirements (ISO 26262). If the driver's absence is detected, the vehicle must be automatically secured against rolling away. Due to this functionality, parking and maneuvering is only possible for the customer with additional non-intuitive actions (e.g., fastening the seatbelt, closing the door).

[0015] In Fig. 3 the state of the art is shown in the form of a flow chart: Conditions B1, B1', B5 and B5' refer to detected driver absence due to an open driver's door, an unfastened driver's seat belt and a released accelerator and / or brake pedal (represented here by three symbols). Condition B1 also includes a switched off engine, e.g. due to automatic engine stop ("MSA Stop"), in a vehicle with only a combustion engine. Condition B1' also includes a non-existent or switched off combustion engine (possibly with electric drive readiness) in an electric vehicle or a hybrid vehicle (BEV, PHEV). Condition B5 also includes a switched on engine, e.g. when "MSA Stop" is prevented, in a vehicle with only a combustion engine. Condition B5' also includes a switched on combustion engine in a hybrid vehicle (PHEV).

[0016] All conditions B1, B1', B5, and B5' initially activate the automatic roll-away protection system "AUTO-P." If conditions B1 and B1' are met, the "off" display also appears to indicate that the vehicle is ready to drive, as well as a prompt M1 to secure the vehicle against rolling away if the driver intends to park the vehicle. If condition B2 is met, i.e., if the driver actually leaves the vehicle, AUTO-P is maintained and, for example, the system switches to a comfort exit (KA).

[0017] However, if, according to the state of the art, there is an intention to maneuver B6 by actuating the brake (B3), by engaging gear D or R and then releasing the brake pedal (B4), maneuvering cannot take place because the automatic anti-roll device “AUTO-P” is in an endless loop.

[0018] According to the invention, the current vehicle behavior for normal driving in the near-standstill range should generally be maintained in order to continue to ensure the safety requirements.

[0019] But in addition, limited shunting operations will be introduced in compliance with the above-mentioned safety criteria with an adapted warning strategy (display in the instrument cluster).

[0020] Shunting operations are applied to all types of drive, i.e. combustion engines, hybrids and purely electric drives.

[0021] This limited shunting operation enables shunting within specified boundary conditions (exit conditions) following a conscious shunting request by the driver, in particular after re-engaging the gear (“D” or “R”) after the vehicle has been automatically secured (entry conditions).

[0022] This better meets customer needs in a variety of parking and maneuvering situations. Furthermore, the vehicle's functional availability is increased.

[0023] Embodiments of the invention are illustrated in the drawing and are described in more detail below. Fig. 1 a functional overview of the automatic roll-away protection system “AUTO-P” with limited maneuvering operation according to the invention in a vehicle with an internal combustion engine, Fig. 2 a functional overview of the automatic anti-roll device “AUTO-P” with limited maneuvering operation according to the invention in a vehicle with electric drive, Fig. 3 a functional overview of the automatic roll-away protection “AUTO-P” according to the state of the art, Fig. 4 a first table with examples of switch-off conditions and subsequent reaction options as well as Fig. 5 a second table with further examples of switch-off conditions and subsequent reaction options.

[0024] According to Fig. 1, an electronic control unit (not shown in detail here) is designed, in particular with a software program module, in such a way that, according to the invention, a limited shunting operation RB is enabled within defined boundary conditions in accordance with predetermined entry conditions and in accordance with predetermined exit conditions AK.

[0025] A predefined entry condition is defined as a conscious manoeuvring request by the driver after the vehicle has been automatically secured “AUTO-P”: A conscious maneuvering intention of the driver can be determined by condition B3, namely re-engaging gear D or R while initially depressing the brake pedal BP, and by condition B4, namely subsequently releasing the brake pedal BP. The entry condition is preferably determined by the driver's conscious maneuvering intention determined by conditions B3 and B4 within a specified time window dt.

[0026] A predefined entry condition can preferably be used in conjunction with condition B1, i.e. when the combustion engine is switched off and when the driver is detected as absent (see the three symbols, as in Fig. 3), the previous automatic protection "AUTO-P" may be used, even if it has been activated and deactivated as often as desired. In other words, the drive-ready state remains switched on; this is preferably indicated to the driver with a corresponding display, e.g., "READY" instead of "OFF" (according to the state of the art; Fig. 3) communicated.

[0027] In contrast, a predefined entry condition in conjunction with condition B5, i.e., when the combustion engine is running and driver absence is detected, is preferably only a single prior automatic backup "AUTO-P" (1x). This is preferably also communicated to the driver with a corresponding display.

[0028] Fig. 2 corresponds essentially to Fig. 1 with the difference that the invention according to Fig. 2 applies to an electric vehicle or a hybrid vehicle with an electric motor and, where applicable, a combustion engine. In such a vehicle, the message M1 is replaced by the message M2, in which the driver is instructed, in particular, to close the door to continue driving or to press the start / stop button to switch off the electric motor and to engage the transmission position P to get out. Furthermore, according to Fig. 2 (upper dashed box) electric limited shunting operation RB_e can be enabled by the electric drive readiness when the combustion engine is not present or is switched off.

[0029] The Fig. 4 and Fig.5 shows various predeterminable exit conditions AK from the limited shunting operation RB or RB_e in tabular form. According to the invention, the exit conditions AK that lead to the reactivation of the "AUTO-P" anti-rollover system are particularly relevant. According to the invention, such an exit condition AK is the vehicle starting to move and exceeding a speed threshold (>10 km / h). Other exit conditions AK are, in particular: - a further standstill of the vehicle for a specified time (1 s) after releasing the brake pedal (BP) - the vehicle starts moving without pressing the accelerator pedal (this is not necessarily a condition for exiting the vehicle).

Claims

[1] Control system for automatically activating or deactivating a roll-away protection system (AUTO-P) in motor vehicles with at least one electronic control unit, which is designed in such a way that a limited maneuvering operation (RB; RB_e) is possible within specified boundary conditions according to specified entry conditions and according to specified exit conditions (AK), wherein a specified entry condition is defined as a conscious maneuvering request of the driver after prior automatic securing (AUTO-P) of the vehicle, characterized by that a predetermined exit condition (AK) is that the vehicle starts moving and exceeds a speed threshold, after which the roll-away protection (AUTO-P) is reactivated when the vehicle is next stationary, whereby the exit condition (AK) describes a case in which a transition to driving with the door ajar occurs. [2] Control system according to claim 1, characterized bythat a conscious manoeuvring wish of the driver can be detected by re-engaging the gear (D / R) while initially pressing and then releasing the brake pedal (BP), whereby the detected conscious manoeuvring wish within a predetermined time window (dt) is specified as the entry condition. [3] Control system according to one of the preceding claims, characterized by that a given entry condition (B1, B1') continues to be an arbitrarily frequent previous automatic backup (AUTO-P) with the engine previously switched off ("READY"). [4] Control system according to one of the preceding claims, characterized by that a given entry condition (B5, B5') continues to be only a single previous automatic backup (AUTO-P) with the engine running (1x). [5] Control system according to one of the preceding claims, characterized bythat a predetermined exit condition (AK) is a further standstill of the vehicle for a predetermined time after the brake pedal (BP) is released, after which the roll-away protection system (AUTO-P) is activated again. [6] Control system according to one of the preceding claims, characterized by that a predefined exit condition (AK) is that the vehicle starts moving without pressing the accelerator pedal, after which the roll-away protection system (AUTO-P) is reactivated. [7] Software function module for the at least one electronic control unit of a control system according to one of the preceding claims.

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