SE540548C2 - Method and system for preventing automatic disengagement of a clutch - Google Patents

Abstract

SUMMARYMethod (300) and control system (290) for overriding a rule in a control system (290), controlling a clutch (240) via an actuator (255) for opening / closing a powertrain between an engine (220) and a gearbox ( 260), by requesting the control system (290) to prevent rulegoverned disengagement of the clutch (240). The method (300) comprises determining (301) position of a clutch pedal (200); checking (302) if the determined (301) position of the clutch pedal (200) is within a first position zone (201), where the control system (290) is prevented to disengage the clutch (240); and preventing (303) the control system (290) to disengage the clutch (240) when the position of the clutch pedal (200) is determined to be in the first position zone (201).

Description

METHOD AND SYSTEM FOR PREVENTING AUTOMATIC DISENGAGEMENT OF A CLUTCH TECHNICAL FIELD This document discloses a method and a control system. More particularly, a method and a control system is described, for requesting a control system which is controlling a clutch via an actuator for opening/ closing a powertrain between an engine and a gearbox, to prevent automatic disengagement of the clutch.

BACKGROUND In a vehicle, a clutch lever such as a clutch pedal may sometimes be used to opening/ closing the connection between an engine and a gearbox, e.g. when changing gears. This applies both when driving a vehicle with a manual transmission and a so-called Automated Manual Transmission (AMT) - gearbox. It may also be possible to shift gears when there is no driving torque in the powertrain, i.e. when the clutch is engaged but there is no torque transferred in the gearbox. When driving a vehicle with AMT gearbox, the driver may sometimes be enabled to select between manual gear shift and automatic gear shifting via a control system.

Such vehicle comprises e.g. a truck, a bus, a lorry, a car, or similar means for transportation designed for land-based geographical movement.

In some such vehicles, the clutch lever may comprise a clutch pedal operated with the foot while e.g. when riding a motorcycle, snowmobile or quad bike, the clutch lever may be operated by the driver’s hand.

The clutch lever traditionally comprises a mechanical or hydraulic linkage to the clutch, whereby the power transmission between the engine and transmission is interrupted when the clutch lever is pressed. Clutch-By-Wire (CBW) is a recently developed technology, which lacks traditional physical mechanical or hydraulic linkage to the clutch. Instead, the clutch is regulated electronically by detecting the position of the clutch lever and generating control signals for controlling the clutch via an actuator over a wired or wireless interface by control signals corresponding to the determined position of the clutch lever.

Thus when the driver is in control of the clutch, the clutch pedal position is mapped to a calibratable clutch torque.

When utilising a Clutch-By-Wire vehicle, the driver is enabled to select between driver control of the clutch, and system control of the clutch. The system control of the clutch works much in the same way as is made in a vehicle without clutch pedal, i.e. gear shift is made based on engine speed etc., such that an upshift of gears may be made when the engine speed exceeds a threshold value and vice versa.

A problem that however may occur in some situations when the clutch is system controlled is that the driver does not want the system to disengage automatically even though it normally would. An example of this is when driving a heavily loaded timber truck downhill and braking, even when the speed is so low that the engine speed drops below the idle speed.

In some conventional solutions concerning Clutch-By-Wire, there is no possibility for the driver to override the predetermined rules that regulates the control system. In other conventional solutions, a dedicated button on the control panel of the vehicle may be used for this purpose.

It is thus desired to find a convenient and driver friendly way of enabling the driver to override at least some of the control system rules, at least in some particular situations, instead of always following predetermined rules for engaging/ disengaging the clutch.

SUMMARY It is therefore an object of this invention to solve at least some of the above problems and improve regulation of a clutch control system.

According to a first aspect of the invention, this objective is achieved by a method for preventing automatic disengagement of a clutch by a control system, which clutch is situated between an engine and a gearbox and is adapted to allow or interrupt torque transfer between the engine and the gearbox. The method comprises determining the position of a clutch pedal. Further, the method comprises checking if the determined position of the clutch pedal is within a first position zone in which the control system is prevented from automatically disengaging the clutch. In addition, the method comprises preventing the control system from automatically disengaging the clutch if the clutch pedal is determined to be within the first position zone.

According to a second aspect of the invention, this objective is achieved by a control systern configured for automatic disengagement of a clutch, situated between an engine and a gearbox and is adapted to allow or interrupt torque transfer between the engine and the gearbox. The control system comprises a computing unit, configured for determining posi tion of a clutch pedal by a sensor. Further, the control system also comprises a control unit, configured for obtaining the determined position of the clutch pedal from the computing unit. The control unit is also configured for checking if the determined position of the clutch pedal is within a first position zone, in which the control system is prevented from automatically disengaging the clutch. In addition, the control unit is further configured for preventing the control system from automatically disengaging the clutch when the position of the clutch control is determined to be in the first position zone.

Thanks to the introduced first position zone, and by enabling the driver to depress the clutch pedal for placing the clutch pedal in the first position zone, the driver is given a possibility to override the control system andcontrol the clutch. Thus the driver can request the control system to prevent rule-governed automatic disengagement of the clutch.

Advantages therewith is that the driver is provided with greater freedom to control the vehicle behaviour and override certain predetermined rules governing the clutch control system of the vehicle. This is made without introducing additional hardware controls or crowding the control panel with additional controls. Further, controlling the behaviour of the clutch control system by the clutch pedal is natural and intuitive for the driver. Thereby an improved regulation of the clutch control system is achieved.

Other advantages and additional novel features will become apparent from the subsequent detailed description.

FIGURES Embodiments of the invention will now be described in further detail with reference to the accompanying figures, in which: Figure 1 illustrates a vehicle according to an embodiment; Figure 2A schematically illustrates a vehicle powertrain according to an embodiment; Figure 2B illustrates a clutch pedal according to an embodiment; Figure 3 is a flow chart illustrating an embodiment of the method; Figure 4 is an illustration depicting a control system according to an embodiment.

DETAILED DESCRIPTION Embodiments of the invention described herein are defined as a method and a control systern, which may be put into practice in the embodiments described below. These embodimerits may, however, be exemplified and realised in many different forms and are not to be limited to the examples set forth herein; rather, these illustrative examples of embodiments are provided so that this disclosure will be thorough and complete.

Still other objects and features may become apparent from the following detailed description, considered in conjunction with the accompanying drawings. It is to be understood, however, that the drawings are designed solely for purposes of illustration and not as a definition of the limits of the herein disclosed embodiments, for which reference is to be made to the appended claims. Further, the drawings are not necessarily drawn to scale and, unless otherwise indicated, they are merely intended to conceptually illustrate the structures and procedures described herein.

Figure 1 shows a vehicle 100, designed for shifting gears and motor performance in e.g. a first direction 105 on a road 110. The vehicle 100 may comprise e.g. a truck, a bus or a car, or any similar vehicle or other means of conveyance.

The vehicle 100 has an electronic clutch, sometimes referred to as Clutch -By -Wire, or CBW, wherein conventional mechanical or hydraulic linkage to the clutch has been replaced by an electronic control system using an electromechanical actuator, or any other alternative actuator, and an interface that emulates the pedal and steering feel of the clutch pedal. With the Clutch -By -Wire, there is no physical/ mechanical linkage between the clutch pedal and the clutch. Instead, there are one or more sensors that detect the position/ displacement of the clutch pedal, e.g. by measuring the resistance of a resistor. This information is collected, translated and control signals are sent via a control system to the actuator that controls the clutch according to the detected position of the clutch pedal when the clutch is in driver control mode.

Thanks to Clutch -By -Wire, less mechanical components are needed. Thereby, vehicle weight may be decreased and also positioning of the clutch and powertrain in relation to the clutch lever is simplified during manufacturing of the vehicle 100. Further, it is possible that manufacturing costs may be reduced, due to simplified assembly.

Figure 2A schematically shows a powertrain of the vehicle 100 according to an embodiment of the present invention. The powertrain comprises an internal combustion engine 220. The combustion engine 220 is connected via an output shaft 230 to a gearbox 260 via a clutch 240. The clutch 240 is a mechanical device configured to open and close, respectively the power transmission, thereby allowing/ interrupting torque transfer to the gearbox 260. Friction elements of the clutch 240 may be engaged with a flywheel on the engine output shaft 230. A pressure plate may be spring loaded, and may put pressure on the friction elements of the clutch 230, forcing them into engagement with the flywheel when the clutch 230 is engaged. The pressure plate may be laterally displaceable by means of for example a lever arm, whose function may be controlled by an actuator 255. The actuator 255 may comprise e.g. an Electronic Clutch Actuator (ECA), a Power Control Actuator (PCA), or any other appropriate type of actuator. Thus, by moving the lever arm via the actuator 255, the pressure of the pressure plate on the friction elements of the clutch 230 may be gradually eased as the pressure plate is separated from the friction elements by the lever arm.

The clutch 240 may in some embodiments comprise one or more electric motors, acting as clutches, e.g. in, or in association with a gearbox. In some embodiments, the clutch 240 may comprise a single clutch or a double clutch in different embodiments. Further, the clutch 240 alternatively may comprise a torque converter, e.g. in an automatic gearbox.

The clutch 240 is thus located between the engine 220 and the gearbox 260, as disengaging it may facilitate a gear change. The clutch 240 may typically be utilised during vehicle take off, switching from disengaged mode into engaged mode, enabling a smooth start, or during gear shifts. The output shaft 270 of the gearbox 260 is connected to the final drive, and then the driving wheels 280-1, 280-2, via drive shafts.

In Figure 2A is schematically only two driving wheels 280-1, 280-2 illustrated but embodiments of the invention is applicable also to vehicles 100 with a plurality of drive shafts, which each may be provided with one or several driving wheels.

With the clutch 240 disengaged, the gearbox input shaft is free to change its speed as the internal ratio of the gearbox 260 is changed. Any resulting difference in speed between the engine output shaft and gearbox input shaft is eliminated as the clutch 240 slips during reengagement.

The clutch 240 may be opened and closed by the actuator 255 e.g. via the lever arm in some embodiments. However, in some embodiments, the actuator 255 may operate directly on the clutch 240 for open/ closing operations. The effect of the actuator 255 on the lever arm may in turn be controlled by the vehicle clutch control system 290 via a control unit 250. Further, the clutch 240 may be both system controlled and/ or driver controlled.

The vehicle 100 may further comprise a cabin which may be provided with a driver environment with instruments, controls, etc. Within the driver environment, a clutch lever 200 may be situated for controlling the clutch 240 when in driver control mode. Typically, the clutch lever 200 may comprise a clutch pedal in some embodiments. Subsequently, the expression clutch pedal 200 will be used for increased clarity, even if e.g. hand manoeuvred clutch levers may also be used.

A sensor 205 situated adjacent to the clutch pedal 200 may be configured for detecting position of the clutch pedal 200. A computing unit 210 is configured for determining position of the clutch pedal 200 by obtaining sensor signals from the sensor 205. The sensor 205 may comprise e.g. a potentiometer in some embodiments. However, the sensor 205 may in alternative embodiments comprise a set of photo cells, be based on measurements by laser, ultrasound or similar. The sensor 205 may furthermore comprise e.g. an angular sensor or similar, configured for estimating the angular inclination of the clutch pedal 200.

The computing unit 210 may receive measurements from the sensor 205. The computing unit 210 is configured for determining position of the clutch pedal 200 by obtaining sensor signals from the sensor 205. The determined position of the clutch pedal 200 may then be provided to the control unit 250, which in turn may generate control signals for controlling the clutch 240, via the actuator 255, according to the displacement, i.e. depression of the clutch pedal 200.

This driver environment may also comprise an information interface for displaying information to the driver of the vehicle 100. This information interface may comprise, for exampie, a monitor, a lamp / diode, a speaker, a vibration exciter for tactile feedback or the like. Information related to the clutch 240, such as current driving mode (which may be system control mode or driver control mode), position of the clutch pedal 200 or similar may thereby be communicated to the driver, possibly together with additional information.

In the illustrated example in Figure 2A, the control system 290 comprises the calculation unit 210 and the control unit 250. However, the control system 290 may in other embodiments comprise another number of units. Further, the distribution of computations may be distributed differently between the constituent units within the control system 290 in different embodiments. The control system 290 in the vehicle 100 may comprise a communication bus system comprising one or more communication busses to interconnect a number of Electronic Control Units (ECUs), or control units/ controllers, and various other components located on the vehicle 100. Such a control system 290 may thus comprise e.g. a large number of control units, each responsible for a specific function. Further, such specific function may be divided into more than one control unit in some embodiments. Also, a single control unit may be configured to be responsible for a plurality of functions.

The control unit 250, which may comprise a Transmission Control Unit (TCU), is thus configured to communicate with other devices e.g. for receiving signals and measured values etc., such as the calculating unit 210. Further, the control unit 250 may be configured to communicate e.g. via the vehicle communication bus, which may comprise one or more of a cable; a data bus, such as a CAN bus (Controller Area Network bus), a MOST bus (Media Oriented Systems Transport), or any other convenient bus configuration.

The control unit 250 and / or the calculating unit 210 may also in addition, or alternatively, be configured for wireless communication over a wireless interface according to some embodiments. The wireless interface may comprise radio transmitters based on, or at least inspired by wireless communication technology such as Wi-Fi, Wireless Local Area Network (WLAN), Ultra Mobile Broadband (UMB), Bluetooth (BT), Near Field Communication (NFC) or infrared transmitter to name but a few possible examples of wireless communications.

Figure 2B illustrates an embodiment wherein the clutch pedal 200 may be situated in different zones when depressed from its released starting position, such as a first position zone 201, a second position zone 202 and possibly also a deactivated zone 203. Further, the clutch pedal 200 may be situated in a released position 204 when the clutch pedal 200 is not depressed at all.

By defining the first position zone 201 and the second position zone 202 and determine different control states based on in which zone 201, 202 the clutch pedal 200 is situated it may be prevented that the control system 290 switch automatically from controlling the clutch 240, into driver control mode. In some embodiments, also the third deactivated zone 203 may be defined, in which disengagement and hand over from system control, to driver control may be permitted. Thereby, the driver is given control in a natural and intuitive manner, over when the control system 290 may hand over control over the clutch 240, and when to inhibit such disconnection.

When the clutch pedal 200 is determined to be in the second position zone 202 comprised in some embodiments, the control system 290 is not prevented from automatic disengagement of the clutch 240, i.e. when the driver depress the clutch pedal 200 into the second position zone 202. Thereby, the control system 290 is enabled to automatically disengage the clutch 240 when the driver places the clutch pedal 200 in the second position zone 202, in case e.g. the engine speed falls below a threshold value. Thus the control system 290 may work as normal when the clutch pedal 200 is situated in the second position zone 202.

The second position zone 202 may be situated beyond the first position zone 201 within the trajectory of the clutch pedal 200, such that the clutch pedal 200 has to pass the first position zone 201 before reaching the second position zone 202, when the clutch pedal 200 is depressed from a released position 204. An advantage with having the second position zone 202 is that the driver may control the prevention and allowance respectively, of automatic disengagement of the clutch 240 by the control system 290. Yet an advantage by placing the second position zone 202 beyond the first position zone 201 within the trajectory of the clutch pedal 200 is that in case the control system 290 disengage the clutch 240, a switch may be made to driver controlled clutch 240, wherein the clutch 240 is open as the clutch pedal 200 is depressed.

The optional third deactivated zone 203 may be situated closer to the released position 204 of the clutch pedal 200, than the other zones 201, 202. By providing the deactivated zone 203, between the released position 204 of the clutch pedal 200 and the first position zone 201, the risk that the driver unintentionally place the clutch pedal 200 in the first position zone 201 when e.g. unintentionally slightly touching the clutch pedal 200, may be reduced.

In some embodiments, a feedback may be provided to the driver, informing the driver about the zone position of the clutch pedal 200, i.e. in the first position zone 201 or the second position zone 202 (or possibly in some embodiments, the deactivated zone 203).

For example, the clutch pedal 200 may be provided with a first resilience, or resistance, when positioned within the first position zone 201 and a second resilience when positioned within the second position zone 202 in some embodiments. In further embodiments, the position switch from the first position zone 201 into the second position zone 202 may be marked with a haptic feedback like e.g. a "click feel" of the pedal resilience or the like to give the driver better feedback. In a similar manner, according to some embodiments, the position switch from the deactivated zone 203 into the first position zone 201 may be marked with a haptic feedback like e.g. a "click feel" of the pedal resilience or the like to give the driver better feedback.

Thanks to this arrangement, the driver is provided with a possibility to override the predetermined rules controlling the engagement/ disengagement of the clutch control system 290 and may prevent the control system 290 from disengaging the clutch 260 in a situation when it normally is set to disengage automatically, e.g. due to low engine speed.

In some embodiments, the first position zone 201 wherein the control system 290 is prevented to disengage the clutch 240, may be reached directly after the driver has started to depress the clutch pedal 200, i.e. after having depressed the clutch pedal 200 from the released position 204, or alternatively after having started to depress the clutch pedal 200 from the released position 204 and passed the third deactivated zone 203.

Further, by providing a solution based on positioning of the clutch pedal 200, an easy and driver friendly solution is achieved. The driver may prevent the control system 290 to disengage the clutch 240 without having to use his / her hands, whereby traffic security is enhanced, as he/ she may keep both hands on the steering wheel. Yet an advantage is that the driver in this way may get control over the clutch 240 in a natural and intuitive way.

Further, by providing the control functionality by placing the clutch pedal 200 in different zones 201, 202, instead of e.g. placing a control button on the control panel, economic advantages are achieved, as less hardware has to be installed into the vehicle 100.

Figure 3 illustrates an example of a method 300 according to an embodiment. The flow chart in Figure 3 shows the method 300 for overriding a rule in a control system 290. The control system 290 is configured for controlling a clutch 240 via an actuator 255 for opening/ closing a powertrain between an engine 220 and a gearbox 260. The method 300 thereby prevent automatic disengagement of the clutch 240 and override the control system 290 by requesting the control system 290 to prevent rule-governed disengagement of the clutch 240.

The clutch 240 may thus be system controlled, or driver controlled. The clutch pedal 200 may be an electronic clutch control which may comprise or be based on a clutch-by-wire solution and comprise for example a pedal or a handle in different embodiments.

By placing the clutch pedal 200 in a first position zone 201, the driver may override the control system 290 to prevent rule-governed disengagement of the clutch 240.

When the driver places the clutch pedal 200 in the second position zone 202, the control system 290 is not prevented from automatic disengagement of the clutch 240 in some embodiments. Thereby, the control system 290 may disengage the clutch 240.

The driver may control the clutch 240 in conventional manner whether the clutch pedal 200 is situated in the first position zone 201 or the second position zone 202, i.e. by opening the clutch 240 more, the more the clutch pedal 200 is depressed.

Thereby the driver may be given control over the control system 290 as well as over the clutch 240.

The second position zone 202 may be situated beyond the first position zone 201 within the trajectory of the clutch pedal 200, such that the clutch pedal 200 has to pass the first position zone 201 before reaching the second position zone 202, when the clutch pedal 200 is depressed from released position/ deactivated zone 203, or depressed from a released position 204.

The passage between the first position zone 201 and the second position zone 202, and / or between the third deactivated zone 203 and the first position zone 201 may according to some embodiments be associated with a haptic feedback provided to the driver. Such haptic feedback may comprise any, or a combination of e.g. a changing pedal resilience, a vibration and / or a sound.

Thus, in some embodiments, the first position zone 201 and the second position zone 202 and / or the third deactivated zone 203 may be associated with different pedal resilience.

According to yet some embodiments, the first position zone 201 may be situated beyond the deactivated zone 203, wherein the method 300 is deactivated, within the trajectory of the clutch pedal 200, such that the clutch pedal 200 has to pass the deactivated zone 203 before reaching the first position zone 201, when the clutch pedal 200 is depressed from released position 204 by the driver.

In some embodiments, a visual feedback may be provided to the driver, illustrating the position of the clutch pedal 200 within any of the first position zone 201, the second position zone 202 and/ or the deactivated zone 203.

In order to correctly be able to override the control system 290, the method 300 may comprise a number of steps 301-305. However, some of these steps 301-305 may be performed solely in some alternative embodiments, like e.g. step304 and / or 305. Further, some of the steps may be performed in different ways in different embodiments. The method 300 may comprise the subsequent steps: Step 301 comprises determining position of a clutch pedal 200.

The position of the clutch pedal 200 may be determined e.g. by a sensor 205. In some embodiments, the sensor 205 may comprise e.g. a potentiometer configured for measuring resistance. Such potentiometer may be arranged for changing resistance as the clutch pedal 200 is depressed from the released position 204. Thus a particular position of the clutch pedal 200 corresponds to a particular electric resistance within the potentiometer. Thereby, it is possible to determine the position of the clutch pedal 200 by determining the resistance at the potentiometer.

However, in some other alternative embodiments, the sensor 205 may comprise other types of sensors based on e.g. a set of photo cells, be based on measurements by laser, ultrasound or similar.

In some embodiments, the position may be determined, and / or initiation of the method 300 may be triggered when a depression of the clutch pedal 200 from a released position 204 is detected.

By triggering a method start only when the clutch 240 is system controlled and the driver starts pressing down the clutch pedal 200, the method 300 is only performed when the driver actively desires to override the control system 290 by requesting the control system 290 to prevent rule-governed disengagement of the clutch 240.

Further, by initiating the method 300 when the clutch pedal 200 is somewhat depressed from the released position 204, there is no requirement for a particular, dedicated button, switch or the like, for initiating the method 300 for changing clutch control mode. Thereby space is saved on the control panel. Less buttons on the control panel makes it easier for the driver to find and reach other, possibly more urgent vehicle function control in an emergency situation. Further, assembly of the control panel is simplified. Also, less components has to be kept in stock at the vehicle factory.

Step 302 comprises checking 302 if the determined 301 position of the clutch pedal 200 is within a first position zone 201, wherein the control system 290 is prevented to disengage the clutch 240.

Step 303 comprises preventing 303 the control system 290 from automatically disengaging the clutch 240 when the position of the clutch pedal 200 is determined to be in the first position zone 201.

Step 304 may be performed only in some alternative embodiments. The optional action 304 may comprise emitting a haptic feedback when the clutch pedal 200 is moved between the first position zone 201 and the second position zone 202.

In some embodiments, the haptic feedback may be emitted when the clutch pedal 200 is moved between the deactivated zone 203 and the first position zone 201.

The haptic feedback may comprise a change in pedal resilience, a vibration and / or a sound in some embodiments.

Step 305 may be performed only in some alternative embodiments. The optional action 305 may comprise providing a pedal resilience associated with the first position zone 201 when the clutch pedal 200 is determined 301 to be positioned within the first position zone 201, and / or the pedal resilience associated with the second position zone 202 when the clutch pedal 200 is determined 301 to be positioned within the second position zone 202.

In some embodiments, a pedal resilience associated with the deactivated zone 203 may be provided when the clutch pedal 200 is determined 301 to be positioned within the deactivated zone 203.

Thereby, the rule-governed control system 290 controlling the clutch 240 via the actuator 255 of the vehicle 100 may be at least temporarily overridden in a convenient and driver friendly manner and the driver is provided freedom to prevent rule-governed disengagement of the clutch 240 by the control system 290.

Figure 4 illustrates an embodiment of a system 400 for preventing automatic disengagement of a clutch 240 by a control system 290 controlling a clutch 240 via an actuator 255, for opening/ closing a powertrain between an engine 220 and a gearbox 260, by requesting the control system 290 to prevent rule-governed disengagement of the clutch 240. The overriding may be performed by performing at least some of the described steps 301-305, comprised in the method 300 described above and illustrated in Figure 3.

The clutch 240 may in some embodiments comprise a friction clutch. In other embodiments, the clutch 240 may comprise one or more electric motors, acting as clutches, e.g. within, or in association with a gearbox. In some embodiments, the clutch 240 may comprise a single clutch or a double clutch. Further, the clutch 240 alternatively may comprise a torque converter, e.g. in an automatic gearbox.

The system 400 comprises a clutch pedal 200. As already stated, a hand manoeuvred clutch lever may alternatively be utilised in some embodiments, for example in embodiments comprised in certain vehicles 100 like motorbikes, snowmobiles etc.

The system 400 further comprises a sensor 205, configured for detecting the position of the clutch pedal 200. The system 400 additionally comprises an actuator 255 configured for engaging/ disengaging the clutch 240 when instructed by a control system 290, or by the control unit 250 comprised in the control system 290.

Further, the system 400 also comprises the control system 290 configured for controlling the clutch 240 via the actuator 255 for opening/ closing the powertrain between the engine 220 and the gearbox 260.

The control system 290 comprises a computing unit 210, configured for determining position of the clutch pedal 200 by the sensor 205.

In addition, the control system 290 comprises a control unit 250. The control unit 250 is configured for obtaining the determining position of the clutch pedal 200 from the computing unit 210. Also, the control unit 250 is furthermore configured for checking if the determined position of the clutch pedal 200 is within a first position zone 201, in which the control system 290 is prevented to disengage the clutch 240. Additionally, the control unit 250 is also configured for preventing the control system 290 from automatically disengaging the clutch 240 when the position of the clutch control 200 is determined to be in the first position zone 201.

However, in some alternative embodiments, the control system 290 may comprise additional units, besides the above mentioned computing unit 210 and control unit 250. In other embodiments, the control system 290 may comprise one single unit performing the steps 301-305 of the method 300. Further, in some embodiments, the allocation of tasks performed within the control system 290 between the computing unit 210 and control unit 250 may be made differently.

The computing unit 210 may comprise a signal receiver 410, configured for receiving signals comprising or representing measurement values from the sensor 205, in some embodiments.

Also, the computing unit 210 may comprise a processing circuitry 420. The processing circuitry 420 may be configured for determining position of the clutch pedal 200, based on the received signals comprising measurement values received from the sensor 205.

Such processing circuitry 420 may comprise one or more instances of a processing circuit, i.e. a Central Processing Unit (CPU), a processing unit, a processing circuit, a processor, an Application Specific Integrated Circuit (ASIC), a microprocessor, or other processing logic that may interpret and execute instructions. The herein utilised expression “processor” may thus represent a processing circuitry comprising a plurality of processing circuits, such as, e.g., any, some or all of the ones enumerated above.

Furthermore, the computing unit 210 may comprise a memory 425 in some embodiments. The optional memory 425 may comprise a physical device utilised to store data or programs, i.e., sequences of instructions, on a temporary or permanent basis. According to some embodiments, the memory 425 may comprise integrated circuits comprising siliconbased transistors. The memory 425 may comprise e.g. a memory card, a flash memory, a USB memory, a hard disc, or another similar volatile or non-volatile storage unit for storing data such as e.g. ROM (Read-Only Memory), PROM (Programmable Read-Only Memory), EPROM (Erasable PROM), EEPROM (Electrically Erasable PROM), etc. in different embodiments.

Further, the computing unit 210 may comprise a signal transmitter 430. The signal transmitter 430 may be configured for transmitting signals related to the determined position of the clutch pedal 200, calculated by the processing circuitry 420.

Further, the control unit 250, which is also comprised in the control system 290, may comprise a signal receiver 440, configured for receiving signals comprising or representing the determined position of the clutch pedal 200, from the calculating unit 210, in some embodiments.

Also, the control unit 250 may comprise a processing circuitry 450. The processing circuitry 450 may be configured for obtaining the determined position of the clutch pedal 200 from the computing unit 210. Further, the processing circuitry 450 may also be configured for checking if the determined position of the clutch pedal 200 is within a first position zone 201, wherein the control system 290 is prevented to disengage the clutch 240. In addition, the processing circuitry 450 further may be configured for preventing the control system 290 to disengage the clutch 240 when the position of the clutch control 200 is determined to be in the first position zone 201.

Such processing circuitry 450 may comprise one or more instances of a processing circuit, i.e. a Central Processing Unit (CPU), a processing unit, a processing circuit, a processor, an Application Specific Integrated Circuit (ASIC), a microprocessor, or other processing logic that may interpret and execute instructions. The herein utilised expression “processor” may thus represent a processing circuitry comprising a plurality of processing circuits, such as, e.g., any, some or all of the ones enumerated above.

Furthermore, the controlling unit 250 may comprise a memory 455 in some embodiments. The optional memory 455 may comprise a physical device utilised to store data or programs, i.e., sequences of instructions, on a temporary or permanent basis. According to some embodiments, the memory 455 may comprise integrated circuits comprising siliconbased transistors. The memory 455 may comprise e.g. a memory card, a flash memory, a USB memory, a hard disc, or another similar volatile or non-volatile storage unit for storing data such as e.g. ROM (Read-Only Memory), PROM (Programmable Read-Only Memory), EPROM (Erasable PROM), EEPROM (Electrically Erasable PROM), etc. in different embodiments.

Further, the controlling unit 250 may comprise a signal transmitter 460. The signal transmitter 460 may be configured for transmitting control signals for controlling the actuator 255.

The above described steps 301-305 to be performed in the control system 290 may be implemented through the one or more processing circuitries 420, 450 within the computing unit 210 and / or control unit 250, together with computer program product for performing at least some of the functions of the steps 301-305. Thus a computer program product, comprising instructions for performing the steps 301-305 in the control system 290 may perform the method 300 comprising at least some of the steps 301-305 for preventing automatic disengagement of the clutch 240 by the control system 290, which clutch 240 is situated between an engine 220 and a gearbox 260 and is adapted to allow or interrupt torque transfer between the engine 220 and the gearbox 260, when the computer program is loaded into the one or more processing circuitries 420, 450 of the control system 290.

Further, some embodiments may comprise a vehicle 100, comprising the previously described system 400 forcing the control system 290 to prevent rule-governed disengagement of the clutch 240, according to the method 300 comprising at least some of the steps 301-305.

The computer program product mentioned above may be provided for instance in the form of a data carrier carrying computer program code for performing at least some of the actions 301-305 according to some embodiments when being loaded into the one or more processing circuitries 420, 450 of the control system 290. The data carrier may be, e.g., a hard disk, a CD ROM disc, a memory stick, an optical storage device, a magnetic storage device or any other appropriate medium such as a disk or tape that may hold machine readable data in a non-transitory manner. The computer program product may furthermore be provided as computer program code on a server and downloaded to the control system 290 remotely, e.g., over an Internet or an intranet connection.

The terminology used in the description of the embodiments as illustrated in the accompanying drawings is not intended to be limiting of the described method 300; the control system 290; the computer program; the system 400 and / or the vehicle 100. Various changes, substitutions and / or alterations may be made, without departing from invention embodiments as defined by the appended claims.

As used herein, the term "and / or" comprises any and all combinations of one or more of the associated listed items. The term “or” as used herein, is to be interpreted as a mathematical OR, i.e., as an inclusive disjunction; not as a mathematical exclusive OR (XOR), unless expressly stated otherwise. In addition, the singular forms "a", "an" and "the" are to be interpreted as “at least one”, thus also possibly comprising a plurality of entities of the same kind, unless expressly stated otherwise. It will be further understood that the terms "includes", "comprises", "including" and / or "comprising", specifies the presence of stated features, actions, integers, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, actions, integers, steps, operations, elements, components, and/ or groups thereof. A single unit such as e.g. a processor may fulfil the functions of several items recited in the claims. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage. A computer program may be stored/ distributed on a suitable medium, such as an optical storage medium or a solidstate medium supplied together with or as part of other hardware, but may also be distributed in other forms such as via Internet or other wired or wireless communication system.

Claims (9)

PATENT CLAIMS

1. A method (300) for preventing automatic disengagement of a clutch (240) by a control system (290), which clutch (240) is situated between an engine (220) and a gearbox (260) and is adapted to allow or interrupt torque transfer between the engine (220) and the gearbox (260), wherein the method (300) comprises the steps of: - determining (301) the position of a clutch pedal (200); - checking (302) if the determined (301) position of the clutch pedal (200) is within a first position zone (201) in which the control system (290) is prevented from automatically disengaging the clutch (240); - preventing (303) the control system (290) from automatically disengaging the clutch (240) if the clutch pedal (200) is determined to be within the first position zone (201); wherein the control system (290) is not prevented from automatic disengagement of the clutch (240) when the clutch pedal (200) is determined to be in a second position zone (202), and wherein the second position zone (202) is situated beyond the first position zone (201) within the trajectory of the clutch pedal (200), such that the clutch pedal (200) has to pass the first position zone (201) before reaching the second position zone (202), when the clutch pedal (200) is depressed from a released position (204), characterised in that the passage between the first position zone (201) and the second position zone (202) is associated with a haptic feedback and/or a sound provided to a driver, which haptic feedback comprises a changing pedal resilience and/or a vibration, and wherein the method (300) further comprises: - emitting (304) the haptic feedback or sound when the clutch pedal (200) is moved between the first position zone (201) and the second position zone (202).

2. The method (300) according to claim 1, wherein the first position zone (201) and the second position zone (202) are associated with different pedal resilience and wherein the method (300) further comprises: providing (305) the pedal resilience associated with the first position zone (201) when the clutch pedal (200) is determined (301) to be positioned within the first position zone (201), or providing the pedal resilience associated with the second position zone (202) when the clutch pedal (200) is determined (301) to be positioned within the second position zone

3. The method (300) according to claim 1, wherein the first position zone (201) and the second position zone (202) are associated with different pedal resilience and wherein the method (300) further comprises: providing (305) the pedal resilience associated with the first position zone (201) when the clutch pedal (200) is determined (301) to be positioned within the first position zone (201), and providing the pedal resilience associated with the second position zone (202) when the clutch pedal (200) is determined (301) to be positioned within the second position zone (202).

4. The method (300) according to any of claims 1-3, wherein the first position zone (201) is situated beyond a deactivated zone (203), wherein the method (300) is deactivated, within the trajectory of the clutch pedal (200), such that the clutch pedal (200) has to pass the deactivated zone (203) before reaching the first position zone (201), when the clutch pedal (200) is depressed from the released position (204).

5. The method (300) according to any of claims 1-4, further comprising providing a visual feedback to the driver, illustrating the position of the clutch pedal (200) within any of the first position zone (201), the second position zone (202) and / or the deactivated zone (203).

6. A control system (290) configured for automatic disengagement of a clutch (240), situated between an engine (220) and a gearbox (260) and is adapted to allow or interrupt torque transfer between the engine (220) and the gearbox (260), wherein the control system (290) comprises: a computing unit (210), configured for determining position of a clutch pedal (200) by a sensor (205); and a control unit (250), configured for obtaining the determined position of the clutch pedal (200) from the computing unit (210), and also configured for checking if the determined position of the clutch pedal (200) is within a first position zone (201), in which the control system (290) is prevented from automatically disengaging the clutch (240); and in addition configured for preventing the control system (290) from automatically disengaging the clutch (240) when the position of the clutch control (200) is determined to be in the first position zone (201), wherein the control system (290) is not prevented from automatic disengagement of the clutch (240) when the clutch pedal (200) is determined to be in a second position zone (202), and wherein the second position zone (202) is situated beyond the first position zone (201) within the trajectory of the clutch pedal (200), such that the clutch pedal (200) has to pass the first position zone (201) before reaching the second position zone (202), when the clutch pedal (200) is depressed from a released position (204), characterised in that the passage between the first position zone (201) and the second position zone (202) is associated with a haptic feedback or sound provided to a driver, which haptic feedback comprises a changing pedal resilience and/or a vibration, and wherein the control system is configured for emitting the haptic feedback or sound when the clutch pedal (200) is moved between the first position zone (201) and the second position zone (202).

7. A computer program comprising program code for performing a method (300) according to any of claims 1-5 when the computer program is executed in a control system (290) according to claim 6.

8. A system (400) for preventing automatic disengagement of a clutch (240) by a control system (290) controlling the clutch (240) via an actuator (255), for allowing or interrupting torque transfer between the engine (220) and the gearbox (260), by requesting the control system (290) to prevent automatic disengagement of the clutch (240) according to a method (300), wherein the system (400) comprises: a clutch pedal (200); a sensor (205), configured for detecting the position of the clutch pedal (200); a control system (290) according to claim 6, and an actuator (255) for engaging/ disengaging the clutch (240).

9. A vehicle (100) comprising a system (400) according to claim 8.