Cruise control system for motor vehicles

Abstract

Cruise control system for motor vehicles with an electronic control unit (EC) that generates control signals (a, b) for regulating the speed of the motor vehicle at least to a predetermined target speed, and with a control element (T1, T2, T3) whose actuation results in an intervention influencing the cruise control, characterized in that the control element is designed as a button (T1), and that when the button (T1) is pressed for a longer period (p1I), the active cruise control is intervened in such a way that no drive torque is generated and that after the button is pressed, the original cruise control is continued.

Description

[0001] The invention relates to a speed control system for motor vehicles according to the preamble of claim 1.

[0002] Motor vehicles with cruise control systems have been around for a long time. Most currently available cruise control systems regulate the vehicle's speed to a preset target speed. In addition to these standard cruise control systems, some manufacturers now offer cruise control systems that also include distance control. In principle, the familiar cruise control system, which maintains a specific target speed, is enhanced by an additional distance control function, making this type of distance-based speed control possible even in heavy highway and rural road traffic. This so-called "distance-based speed control" maintains the preset target speed when the vehicle's lane is clear.If a vehicle-mounted distance sensor, which may be radar-based, detects a slower-moving object or vehicle in its lane, the vehicle's speed is adjusted, for example by applying appropriate braking force, to match the speed of the vehicle ahead, thus maintaining a predetermined distance to the object. In some cases, such systems can even bring the vehicle to a complete stop while following.

[0003] In principle, cruise control systems can be switched on, off, and temporarily deactivated using a control element located, for example, on the steering wheel or dashboard, or using a control lever located, for example, near the steering wheel. Furthermore, the cruise control can also be interrupted due to certain driving maneuvers, so that the cruise control system is still technically switched on, but the cruise control function is not currently being executed. An interruption of the cruise control by switching to a so-called standby mode occurs, for example, when the corresponding control element is activated, when the driver presses the brake pedal or handbrake, or due to an automatic vehicle stabilization intervention. The cruise control system is then still switched on, but the control function is not active.

[0004] To reactivate the interrupted cruise control to the previously set target speed, the driver must operate a corresponding control, which is usually located on or near the steering wheel. The cruise control will then adjust to the previously stored target speed. Alternatively, by operating another control while the cruise control is interrupted, it can be reactivated to the current speed as the new target speed.

[0005] EP 1 812 258 B1 further discloses a driver assistance system with at least two operating modes, wherein the driver assistance system has a control element which activates a special safety operating mode of the driver assistance system for the duration of the operation.

[0006] A speed control system is also known in which at least one control element is designed such that different functions are performed depending on the type of actuation. For example, DE 10 2008 027 120 A1 discloses a speed control system with a control element designed as a touch-sensitive button. When the button is pressed, the interrupted speed control is reactivated to the stored target speed. When the button is touched, a display is activated that shows the stored target speed and / or the stored distance, or enlarges a corresponding display. The display remains active for a predetermined time.

[0007] DE 102 05 023 A1 discloses a speed control system with a control element designed as a button, the actuation of which results in a reduction of the target speed for the duration of the actuation.

[0008] Finally, the still unpublished DE 10 2012 205 263 A1 discloses a speed control system with a touch-sensitive button, wherein when the button is pressed a first intervention influencing the speed control is generated and when the button is touched a second intervention influencing the active speed control is generated for the duration of the touching of the button, which can be designed, for example, such that no drive torque is generated for the duration of the touching.

[0009] The object of the invention is to provide a more user-friendly and comfortable cruise control system that allows the driver to easily intervene in the current cruise control on a short-term basis and is also cost-effective.

[0010] This problem is solved by a speed control system according to claim 1. Advantageous further developments result from the dependent claims.

[0011] The speed control system according to the invention is based on a previously known speed control system for motor vehicles with an electronic control unit that generates control signals for regulating the speed of the motor vehicle to a predetermined target speed (and / or, in the case of distance-related speed control systems, to a predetermined distance to a target object driving ahead), and with at least one control element, the actuation of which results in an intervention influencing the speed control.

[0012] The invention is further based on the consideration that for anticipatory, efficient driving with a cruise control system, it is often necessary to deviate from the set speed, in particular to decelerate from the set speed early by coasting or sailing. While one of the aforementioned operating actions (interrupting by actuating a control element or by applying the brakes) does cause the vehicle to coast, reactivating the cruise control is only possible through another manual operating step (switching it on via a control element).

[0013] The invention therefore provides that at least one control element is designed as a button, and that when the button is pressed (for an extended period), the active cruise control is interrupted for the duration of the press in such a way that no drive torque is generated. After the button is pressed, the original active cruise control resumes. This temporary interruption allows the driver to compensate for the lack of anticipation and intention recognition inherent in cruise control.

[0014] For safety reasons, even during the partial interruption of the speed control (at least some drive torque is generated) due to pressing the button, a requested automatic braking intervention can still be carried out. Alternatively, the speed control can be completely interrupted for the duration of the button press, so that neither drive torque nor braking intervention is generated.

[0015] To enable coasting as early as possible and thus save energy, vehicles equipped with an automatic or automated transmission can, for the duration of pressing the button-like control element, not only have the cruise control (at least partially) interrupted, but also engage neutral (or disengage the clutch) and operate the vehicle in a so-called coasting mode. This prevents any deceleration caused by engine braking. After the button is released, the appropriate gear is automatically engaged, the clutch is engaged, and the cruise control is reactivated in normal mode.

[0016] Advantageously, the control element, designed as a button, can also be configured in such a way that it has at least two different functions or influences the speed control in different ways (depending on the type of operation). For example, the control element designed as a button can be configured such that a short press of the button initiates an initial intervention influencing the speed control, while a longer press of the button intervenes in the active speed control for the duration of the press in such a way that at least no drive torque is generated. After the longer press of the button is ended, the original speed control resumes. The initial intervention influencing the speed control is designed differently from the intervention resulting from a longer press of the button, i.e.,Depending on whether the button is pressed briefly or for a longer period, the speed control is affected differently. A distinction between short and long presses can be made, for example, by recognizing a short press if the button is pressed for less than a predefined time interval of, for example, 0.5 seconds.

[0017] Advantageously, the control element, designed as a button, serves as a primary control for activating, deactivating, and / or interrupting the cruise control. A short press of the button interrupts the active cruise control, deactivates the interrupted cruise control, and / or activates the deactivated cruise control. A longer press of the button intervenes in the active cruise control for the duration of the button press, ensuring that at least no drive torque is generated. Thus, the vehicle operates in overrun mode for the duration the button is pressed. For safety reasons, however, automatic braking intervention can still occur if necessary or advisable.

[0018] Alternatively or additionally, the second control element available for setting the current speed as the new target speed can also be designed as a button such that, when the button is pressed briefly with active speed control, the current target speed is set as the new target speed and / or, when speed control is interrupted, the speed control is activated to the current speed as the target speed, and that when the button is pressed for a longer period, the active speed control is intervened in such a way that at least no drive torque is generated.Alternatively or additionally, the third control element provided for reactivating the interrupted speed control to the stored target speed and / or the stored distance can also be designed as a button such that, when the button is pressed briefly, the interrupted speed control to the stored target speed and / or the stored distance is reactivated, and when the button is pressed for a longer period, the active speed control is intervened in such a way that at least no drive torque is generated.

[0019] Analogous to the above explanations, with such designed buttons that make different interventions in the speed control depending on the duration of the actuation or pressing of the button, the speed control can also be completely interrupted for the duration of the pressing of the button, so that neither a drive torque nor a brake intervention is generated.

[0020] To enable coasting as early as possible and thus conserve energy, vehicles equipped with an automatic or automated transmission can, when the button is pressed for an extended period, not only prevent any drive torque (and potentially any braking torque) from being generated, but also engage neutral (or disengage the clutch) and operate the vehicle in a so-called "sailing mode." This also eliminates any deceleration caused by engine braking. After the button is pressed for an extended period, the appropriate gear is automatically engaged, the clutch is engaged, and normal cruise control resumes.

[0021] The invention is explained in more detail below using an exemplary embodiment. The single figure shows a speed control system with a control element designed as button T1 for executing two functions of the speed control system.

[0022] Figure 1 shows a cruise control system with three buttons T1, T2, and T3, which are part of an active cruise control system. The cruise control system further includes an electronic control unit (EC) which, when driving freely, regulates the speed to a preset target speed. When following (the vehicle ahead is traveling slower than the preset target speed), the EC regulates the speed to maintain a preset distance from the vehicle ahead. The speed is regulated by the EC sending either a drive torque signal (a) to a drive unit (A) to accelerate the vehicle or a brake signal (b) to a brake unit (B) to decelerate the vehicle.

[0023] The first control element T1 is designed as a button T1 such that when the button T1 is briefly pressed – whereby a brief press of the button T1 is either directly detected by the button T1 and a corresponding signal p1k is sent to the control unit, or is detected by a control unit evaluation of the time in which the button T1 is pressed – the active cruise control is interrupted in the active state due to the signal p1k transmitted to the control unit SG (or determined in the control unit SG), the interrupted cruise control is deactivated in the interrupted state, and the deactivated cruise control is activated in the deactivated state.If the user presses button T1 for an extended period while the system is active (= p1l), the active cruise control is overridden for the duration of the press due to the signal p1I transmitted to (or determined by) the control unit SG, such that no drive torque a is generated. Additionally, the power transmission between the drive motor and the drive wheels may be interrupted, allowing the vehicle to coast. However, if a predefined minimum distance to a vehicle ahead is breached (e.g., if the vehicle ahead brakes sharply), a brake signal b is still sent to the brake unit B to decelerate the vehicle. After the extended press of button T1 is ended, the previously active cruise control resumes, maintaining the set speed and distance.

[0024] Furthermore, the second control element is designed as a simple button T2. ​​When button T2 is pressed, the current target speed is set as the new target speed and regulated to it, based on the signal p2 transmitted to the control unit SG. If cruise control is active, the current target speed is reactivated, and the cruise control is reactivated with the current speed as the new target speed. For the sake of completeness, a third control element T3 is also shown, designed as a simple button T3. When button T3 is pressed, it sends a signal p3 to the control unit SG, which then reactivates the interrupted cruise control to the stored target speed and / or the stored distance.

[0025] The inventive speed control system thus requires only reduced operating effort to temporarily override the speed control. This increases the ease of use of such a system and therefore also customer acceptance. Due to the design of the button, there are no or only minimal additional costs for the system.

Claims

[1] Cruise control system for motor vehicles comprising an electronic control unit (EC) which generates control signals (a, b) for controlling the speed of the motor vehicle at least to a predetermined target speed, and comprising a control element (T1, T2, T3) which, when actuated, results in an intervention influencing the cruise control, characterized by , that the control element is designed as a button (T1), and that when the button (T1) is pressed for a longer period (p1I), the active speed control is intervened in such a way that no drive torque is generated and that after the button is pressed, the original speed control is continued. [2] Speed ​​control system according to claim 1, characterized by, that if the button (T1) is pressed for a longer period of time (p1I), the active speed control is intervened in such a way that the speed control is completely interrupted for the duration of the button being pressed. [3] Cruise control system for a motor vehicle with automatic transmission or automated transmission according to any of the preceding claims, characterized by , that if the button (T1) is pressed for a longer period (p1I), the active speed control is intervened in such a way that at least no drive torque is generated and a power transmission interruption between the drive motor and the drive wheels is brought about. [4] Speed ​​control system according to any of the preceding claims, characterized by, that the button (T1) is designed such that a short press (p1k) of the button (T1) generates an initial intervention influencing the speed control, and that a longer press (p1I) of the button (T1) intervenes in the active speed control for the duration of the press in such a way that at least no drive torque is generated and that after the longer press of the button (T1) ends, the original speed control is continued. [5] Speed ​​control system according to claim 4, characterized by, that the button (T1) is a first control element (T1) for switching on and / or off and / or interrupting the speed control, and that when the button (T1) is pressed briefly (p1k) the active speed control is interrupted and / or the interrupted speed control is deactivated and / or the deactivated speed control is activated, and that when the button (T1) is pressed for a longer period (p1I) the active speed control is intervened in such a way that at least no drive torque is generated. [6] Speed ​​control system according to any of the preceding claims, characterized by, that the button is a second control element (T2) for setting the current speed as the new target speed, and that when the button (T2) is pressed briefly, the current target speed is set as the new target speed when speed control is active and / or when speed control is interrupted, the speed control is activated to the current speed as the target speed, and that when the button is pressed for a longer period, the active speed control is intervened in such a way that at least no drive torque is generated. [7] Speed ​​control system according to any of the preceding claims, characterized by, that the button is a third control element (T3) for reactivating the interrupted speed control to the stored target speed and / or the stored distance, and that when the button (T3) is pressed briefly, the interrupted speed control is reactivated to the stored target speed and / or the stored distance, and that when the button is pressed for a longer period, the active speed control is intervened in such a way that at least no drive torque is generated. [8] Speed ​​control system according to one of claims 4-7, characterized by , that if button (T1) is pressed for a longer period of time, the speed control is completely interrupted for the duration of the button (T1) being pressed. [9] Cruise control system for a motor vehicle with automatic transmission or automated transmission according to any one of claims 4-8, characterized by, that if the button (T1) is pressed for a longer period of time, at least no drive torque is generated for the duration of the button (T1) being pressed and a power transmission interruption between the drive motor and the drive wheels of the motor vehicle is brought about.

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