Method and system for detecting a gear change in a gearbox

Abstract

Method for detecting an upshift in a gearbox, the shift being intended to move from a starting gear to an ending gear without using the clutch, the gearbox comprising a selector shaft movable between a first position corresponding to the starting gear and a second position corresponding to the ending gear, a main angular position sensor delivering a voltage value corresponding to a current angular position of the selector shaft, the method comprising: - iterative acquisition of the voltage value (61) delivered by a main sensor and auxiliary information (71) delivered by an auxiliary sensor arranged on the control mechanism connecting the external control lever to the selector shaft, - determination of a condition for reducing engine torque if the auxiliary information denotes movement on the control mechanism,The reduction is possibly confirmed by the beginning of a rotation of the selection tree. Figure from the abstract: Fig. 6,

Description

Title of the invention: Method and system for detecting a gear change in a gearbox

[0001] The present invention relates to a method and detection system for managing a gear change in a gearbox of a motorized mobile machine.

[0002] The present invention finds particular application in mobile devices of the motor cycle type, such as motorcycles or off-road motorcycles. The mobile devices in question may have two wheels, three wheels, or even four wheels ('quad').

[0003] The mobile machine to which the present invention is applied includes a manually controlled gear-shifting gearbox, i.e., the gear shifting is not automatic.

[0004] The gearbox is a gearbox with discrete ratios, each having a predetermined reduction ratio, that is to say it is not a continuously variable reduction transmission ('variator').

[0005] The mobile device to which the present invention is applied comprises a gear selector shaft and an angular position sensor, referred to herein as the 'main' sensor, which delivers a voltage value corresponding to a current angular position of the selector shaft. Furthermore, it should be noted that there are auxiliary sensors that can be retrofitted to the gear shift lever.

[0006] As regards the engine, here an internal combustion engine, it can be a 4-stroke engine or a 2-stroke engine, moreover the engine can be a single cylinder, a twin cylinder, without excluding other configurations.

[0007] According to a very common configuration, the gear change control is carried out with a foot of the driver, in this case the left foot, by actuating an external gear change control lever.

[0008] We are interested here in a so-called rapid gear change, in particular a gear change without using the clutch. In practice, the driver operates the external gear shift lever with their foot without using the clutch control with their hand, nor changing the position of the throttle grip.

[0009] The advantage of making a quick gear change is mainly for upshifts, when the moving machine is at increasing speed.

[0010] It is known to detect, by means of the aforementioned main sensor, the start of the gear change sequence, and to reduce or eliminate engine torque during the gear change time, in particular to allow the engine speed to fall, so that the engagement of the next higher adjacent gear is easy and quick.

[0011] However, detecting the start of the shift sequence, as described above, implies that the selector shaft is already undergoing a rotational movement. Now, a substantial torque can oppose any rotational movement of the selector shaft, particularly when the gearbox is transmitting a high torque, i.e., when the driver is heavily demanding on the engine of their vehicle to accelerate.

[0012] This means in practice that the effort that the driver has to exert on the external control lever can prove to be quite significant.

[0013] It would be desirable to be able to detect very early the maneuver assigned by the driver on the external control lever.

[0014] The inventors sought to improve the situation, in particular to increase the early detection and robustness of the start of the gear change sequence in order to offer a faster, safer, smoother / fluid gear change.

[0015] To this end, a detection method is proposed for managing an upshift in a gearbox of a mobile machine having an engine, the shift being intended to change from a starting gear to an ending gear, in which the gearbox includes a selector shaft movable between a first stable position corresponding to the starting gear and a second stable position corresponding to the ending gear, the gearbox including a main sensor delivering a voltage value corresponding to a current angular position of the selector shaft, the gearbox including a gear shift control mechanism including an external control lever and a linkage mechanism connecting the external control lever to the selector shaft, the gearbox including an auxiliary sensor capable of detecting a force or movement of at least one part of the control mechanism,the process comprising: , - an acquisition step in which the voltage value corresponding to the angular position of the selection shaft is iteratively acquired using the main sensor, and at least one auxiliary piece of information delivered by the auxiliary sensor is iteratively acquired, - a step of determining a condition for reducing engine torque, the condition for reducing torque being determined according to the information delivered by the auxiliary sensor and / or by the main sensor.

[0016] Thanks to the method proposed here, it is possible to detect early and robustly the start of the gear change maneuver assigned to the external control lever by the driver.

[0017] Advantageously, the reduction of engine torque makes it possible to decrease the effort to be exerted on the external control lever, and thus to increase the flexibility and smoothness of the control of rapid gear changes in the gearbox.

[0018] The phrase "and / or" in the clause "depending on the information provided by the auxiliary sensor and / or by the main sensor" means that the two pieces of information can be used in combination or either one separately individually.

[0019] It must be understood that the gear change is carried out without using the clutch, that is to say without disengaging the clutch.

[0020] It should be noted that the concept of 'torque reduction' encompasses a substantial reduction in torque or a complete elimination of torque. Thus, a typical case will consist of the outright elimination of engine torque for a certain number of crankshaft cycles. In other words, it is expected that if a torque reduction condition occurs, said engine torque reduction condition will cause a torque cut-off of the engine.

[0021] In practice, as soon as the driver exerts force on the external control lever, this triggers a reduction in torque, and this facilitates gear changes.

[0022] It is noted that the main sensor will generally be analog, i.e., of the potentiometric type, while the auxiliary sensor can be either binary, i.e., in the form of an On / Off switch, or analog, i.e., providing continuous information, representing angular or even linear movement. The auxiliary sensor can also be a strain gauge.

[0023] It should be noted that the terms 'first' and 'second' above cover not only the case of shifting from the first to the second gear ratio but also all cases of higher gear ratios. It is therefore understood that the final gear ratio is directly above the initial gear ratio, for example, a final gear ratio of R4 with an initial gear ratio of R3, or, in another example, a final gear ratio of R3 with an initial gear ratio of R2.

[0024] According to one embodiment, a torque reduction condition occurs if the auxiliary information exceeds a first predetermined threshold.

[0025] According to one embodiment, a torque reduction condition occurs if the auxiliary information has a time variation greater than a first time ramp.

[0026] Thus the notion of exceeding the threshold by the auxiliary information must be interpreted broadly and may concern the eigenvalue of the auxiliary information or the rate of change of the auxiliary information.

[0027] An additional criterion verifying the information delivered by the main sensor can also be used.

[0028] If the auxiliary sensor delivers binary information then the threshold corresponds to the transition from 0 to 1 (or vice versa), but in the case where the sensor is analog, the first threshold will typically be a parameterizable or calibrable value.

[0029] The predetermined thresholds are configurable and can be adjusted so that the torque reduction does not trigger in the event of simple vibration or stress reflected by irregularities in the road surface, and conversely so that it does trigger in the case where it is actually the driver who applies force on the external control lever.

[0030] According to one embodiment, a first internal counter is provided which counts the number of sampled occurrences of exceeding the first threshold predetermined by the auxiliary information, and the torque reduction condition is established if the first internal counter exceeds a second configurable threshold. This counter, or another counter, can count the number of sampled occurrences of exceeding the first time ramp concerning the rate of change.

[0031] Thus a single erroneous value can be discarded, that is to say that the process will not trigger the torque reduction in the presence of a single value from the auxiliary sensor which exceeds the first threshold.

[0032] According to one embodiment, the internal counter is decremented over time when the value of the auxiliary sensor falls below the first threshold. For example, the second threshold for the counter can be 3 or 4, and the process maintains very good responsiveness despite the presence of the counter.

[0033] According to one embodiment, the torque reduction condition is established if the auxiliary information delivered by the auxiliary sensor exceeds a predetermined threshold, and if the current voltage value acquired on the main sensor becomes greater than a third predetermined threshold.

[0034] For example, the third predetermined threshold exceeds a first reference value by a first predefined deviation, the first reference value corresponding to the first stable position of the selection tree.

[0035] It is noted that the information delivered by the main sensor confirms the early information given by the auxiliary sensor, and this confirmation is consolidated by the total suppression of torque during the transition from the starting gear to the arrival gear.

[0036] Confirmation is given as soon as the selection tree starts to rotate and moves away from the first stable position, a condition which is materialized by the appearance of the first predefined deviation on the voltage delivered by the main sensor.

[0037] Furthermore, it can be provided that if the main sensor does not confirm the early auxiliary information given by the auxiliary sensor, there is no Torque change. This could correspond to an incomplete maneuver or an impact.

[0038] When the gear change sequence is complete, the engine torque is restored as requested by the driver.

[0039] For example, the motor torque can be restored after a predetermined time delay.

[0040] The present invention also relates to a computer configured to implement the process as defined above.

[0041] The present invention also relates to a computer program product, preferably stored on a non-transient memory medium, comprising instructions which, when executed by at least one processor of the computer, performs the process as defined above.

[0042] The present invention also relates to a control system for managing an upshift in a gearbox of a mobile machine having an engine, the shift being intended to change from a starting gear to an ending gear, the gearbox comprising a selector shaft movable between a first stable position corresponding to the starting gear and a second stable position corresponding to the ending gear, the gearbox comprising a main sensor delivering a voltage value corresponding to a current angular position of the selector shaft, the gearbox comprising a gear shift control mechanism comprising an external control lever and a linkage mechanism connecting the external control lever to the selector shaft, the gearbox comprising an auxiliary sensor capable of detecting a force or movement of at least one part of the control mechanism,The control system includes a computer configured to acquire information from the main sensor and the auxiliary sensor, so as to be able to detect a force exerted by the driver's foot on the external control lever, in order to proceed, if a torque reduction condition occurs, to a reduction of engine torque in advance.

[0043] According to one embodiment, the auxiliary sensor is mounted at the axis of the external control lever and the auxiliary sensor is of the potentiometric analog type and delivers angular information.

[0044] The auxiliary sensor is mounted externally on the gearbox; it can be installed as a retrofit or as a factory option that does not affect the basic compactness of the gearbox. The auxiliary sensor forms a ring around the shaft attached to the external control lever.

[0045] According to one embodiment, the auxiliary sensor is mounted opposite a connecting rod of the linkage mechanism.

[0046] The auxiliary sensor is mounted inside and is thus protected from physico-chemical environmental conditions and potential mechanical aggressions.

[0047] According to one embodiment, the auxiliary sensor is an on / off switch. Such a sensor is inexpensive, reliable, and robust. A Hall effect sensor can typically be chosen.

[0048] According to one embodiment, the auxiliary sensor can be a strain gauge capable of detecting an applied force, even before any movement. This allows for relevant anticipation.

[0049] The invention will be further detailed by describing non-limiting embodiments, and based on the accompanying figures illustrating variants of the invention, in which: [Fig.l] schematically illustrates an area of ​​the gear shift lever on a motorcycle with an example of mounting the auxiliary sensor on the external control lever; [Fig.2] schematically illustrates an example of a linkage mechanism connecting the external control lever to the selector shaft in a motorcycle gearbox; [Fig.3] illustrates a timing diagram of gear changes; [Fig.4] shows a functional diagram of the control system involved in the present invention; [Fig.5] illustrates an example of a timing diagram for shifting from one gear to another, in this case between 2nd and 3rd gear, with an auxiliary switch-type sensor; [Fig.6] illustrates another example of a timing diagram, with an auxiliary potentiometric-type sensor; [Fig.7] shows an example of a logic diagram for determining a motor torque reduction / cut-off condition.

[0050] In the various figures, the same reference numerals designate identical or similar elements. For the sake of clarity, some elements are not necessarily shown to scale.

[0051] The present invention finds particular application in mobile devices of the motor cycle type, such as motorcycles or off-road motorcycles. The mobile devices in question may have two wheels, three wheels, or even four wheels ('quad').

[0052] The application has been illustrated on a motorcycle, with a manually controlled gear-shifting gearbox.

[0053] In the illustrated example, there are five gears in the gearbox, respectively labeled RI, R2, R3, R4 and R5. Of course, the invention is also applicable to configurations with fewer than five gears or more than five gears.

[0054] As known per se, the gearbox includes forks that move sliding gear selectors. The position of the forks is controlled by a gear selector shaft, designated 1.

[0055] According to one embodiment, an angular position sensor 2 is provided, with the rotating part connected in rotation to the ratio selection shaft 1, and the body of the sensor being stationary.

[0056] In this document, the angular position sensor giving the angular position of the selection shaft is also called the "main sensor".

[0057] The angular position sensor 2 delivers a voltage value 61 corresponding to the current angular position of the selection shaft.

[0058] With reference to [Fig.2], the angular position sensor 2 is arranged at the end of the selection shaft.

[0059] The angular position sensor 2 is electrically connected to a control unit, also called a computer, discussed later, by electrical conductors 20.

[0060] The angular position sensor 2 is an analog sensor. In the illustrated example, the angular position sensor 2 is a potentiometric type sensor. It covers an angular range close to 360°. It could cover a smaller range.

[0061] Other types of sensors can also be used, provided that their output resembles an analog value which takes several distinct values ​​depending on the respective ratio engaged.

[0062] The angular position sensor can be installed on an auxiliary wheel engaged with the selector shaft. Regardless of the sensor technology or the sensor installation configuration, the angular position sensor provides, directly or indirectly, an image of the angular position of the selector shaft.

[0063] The gearbox is equipped with a gear change control mechanism 9 comprising an external control lever 3 and a linkage mechanism 4. The linkage mechanism 4 mechanically connects the external control lever 3 to the selector shaft 1 as will be seen below.

[0064] As is well known, and visible in [Fig.1], the control lever 3 is moved by the driver's foot, either upwards (G-up) or downwards (G-Dn) depending on whether the driver wants to shift to a higher or lower gear.

[0065] The control lever 3 is mounted to rotate about the axis X0. More precisely, as seen in [Fig.1], the control lever 3 is mounted fixed to a shaft of axis AX0 which is mounted with a single degree of freedom, namely rotation about the axis X0.

[0066] The control lever 3 is of the impulse type, that is to say that the control lever returns to a rest position in the absence of any input from the driver's foot.

[0067] The control lever 3 cooperates with the selection shaft by means of the linkage mechanism noted 4, a simplified version of which is illustrated in [Fig.2].

[0068] A first connecting rod 41 is linked in rotation with the control lever 3, with rotation around the axis X0.

[0069] A second connecting rod 42 is connected to the first connecting rod 41 by a pivot joint with axis XL. The second connecting rod 42 includes teeth 13 configured to hook the pins IL. The gear selection shaft 1 is mounted for rotation on the gearbox housing with respect to the axis X2.

[0070] The ratio selection tree 1 includes pins 11 actuated by the second connecting rod 42 and indexing grooves 12.

[0071] A third connecting rod 43 with a roller 44 indexes the particular positions of the ratios of the ratio selection shaft 1, the roller 44 fitting into the index hollows 12.

[0072] To complete the understanding about the ratio selection tree 1 and the linkage mechanism 4, the reader may refer to documents US3421384 and US4491031.

[0073] The ratio selection shaft 1 includes generally annular grooves which allow the movement of the forks to be controlled axially, i.e. along the axis X2, by cam effect.

[0074] According to an advantageous aspect of the present invention, an auxiliary sensor is provided on the mobile device capable of detecting a force or movement occurring in the gear change control mechanism.

[0075] In practice, this involves detecting the consequence of an effort exerted by the driver on the external control lever 3. Indeed, as will be seen below, it is advantageous to detect an upshift sequence early, that is, as soon as the driver exerts an upward force on the control lever 3, even before the selection shaft 1 begins to rotate.

[0076] According to a first configuration illustrated specifically in [Fig.1] and also visible in [Fig.2], the auxiliary sensor 7 is mounted at the level of the AX0 axis of the external control lever 3.

[0077] According to this first example, the auxiliary sensor 7 is of the analog potentiometric type. The rotating part is fixed in rotation with the external control lever and the non-rotating, therefore static, part is fixed to the gearbox housing.

[0078] The auxiliary sensor 7 provides angular information representing the displacement of the external control lever relative to its rest position, said rest position being the one that is elastically returned in the absence of external mechanical stress. Electrical conductors 70 are provided to connect the auxiliary sensor 7 to the wiring harness and, functionally, to the control unit 5.

[0079] According to a second configuration illustrated in [Fig.2], the auxiliary sensor 7' is arranged opposite the end 41a of the first connecting rod 41 on the opposite side of the X0 axis. The auxiliary sensor 7' can be, for example, a Hall effect sensor and delivers binary information, i.e. on-or-none, i.e. OFF or ON.

[0080] For example, the auxiliary sensor delivers the ON information when the first connecting rod is perfectly aligned with the rest position and conversely the auxiliary sensor delivers the OFF information when the first connecting rod is away from the rest position.

[0081] Here too, electrical conductors 70' are provided to connect the auxiliary sensor 7' to the wiring harness and functionally extend to the control unit in charge of detecting gear changes.

[0082] In addition, it is not excluded to provide for another implantation of an auxiliary sensor capable of detecting a force or a movement in the control mechanism from the external lever 3 to the selection shaft 1.

[0083] The signals, or the signal delivered, by the auxiliary sensor, also called auxiliary information here, is identified as 71 in figures 5 and 6, whether this information is on or off or analog.

[0084] The timing diagram in [Fig.3] illustrates a complete driving phase from zero speed with the gearbox in neutral N, up to 5th gear and back to 2nd gear.

[0085] More precisely, from the beginning until time t1, the gearbox is in neutral (N). Then, from time t1 to time t2, first gear RI is engaged. From time t2 to time t3, second gear R2 is engaged. From time t3 to time t4, third gear R3 is engaged. From time t4 to time t5, fourth gear R4 is engaged. Finally, at time t5, fifth gear R5 is engaged for upshifting. Times t6, t7, and t8 correspond to downshifts (from R5 to R2).

[0086] It is noted that the voltage delivered by the sensor evolves in steps, each step (VR0, VR1, VR2, VR3, VR4, VR5) corresponds to a particular angular position of the selection shaft (0N, 0R1, 0R2, 0R3, 0R4, 0R5, cf. [Fig.4]).

[0087] Moreover, each bearing corresponds to a particular ratio of the gearbox.

[0088] In the illustrated example, the value delivered by the angular position sensor 2 when the box is in neutral ratio N is around 1.1 Volts. When the box is in ratio RI, the voltage value is VR1. When the box is in ratio R2 the The voltage value is VR2. When the box is at ratio R3, the voltage value is VR3. When the box is at ratio R4, the voltage value is VR4. When the box is at ratio R5, the voltage value is VR5.

[0089] As apparent from [Fig. 4], the control system involved here comprises a control unit 5 which includes at least a first functional block 51 (acronym 'Shift CTrl') in charge of detecting gear ratio changes and a second functional block 52 (acronym 'Trq CTrl') in charge of calculating and applying torque through the engine (internal combustion engine here).

[0090] The control unit 5 ('computer') continuously acquires the voltage delivered by the angular position sensor 2, and the information delivered by the auxiliary sensor 7,7' which will be referred to in this document as "auxiliary information".

[0091] The acquisition step is carried out at an acquisition frequency of at least 100 Hz, for example at 1 kHz. This sampling provides at least one value every 1 millisecond for the voltage delivered by the sensor.

[0092] An upshift without disengaging the clutch typically lasts in practice a few tens of ms.

[0093] Turning now to [Fig. 5], we observe in detail a transition from a starting ratio to an ending ratio; here, in the illustrated example, it is a transition from the 2nd ratio to the 3rd ratio. Of course, what is presented applies, mutatis mutandis, to the transitions R3 -> R4, R4 -> R5, R5 -> R6 as appropriate.

[0094] We start, around the instant ta, for the main sensor, from a first reference value V1 corresponding to the first stable position 01 of the selection tree, and we obtain at the end of the passing sequence a second reference value V2 corresponding to the second stable position 02 of the selection tree (arrival position).

[0095] If the starting ratio is the 2nd ratio then VI = VR2 and 01 = 0R2, and also V2 = VR3 and 02 = 0R3. If the starting ratio is the 3rd ratio then VI = VR3, 01 = 0R3, V2 = VR4 and 02 = 0R4.

[0096] Before time ta, the on / off signal 71 from the auxiliary sensor is taken from a first logic level, OFF or ON depending on the logic applied. The signal from the auxiliary sensor 7 is shown at the bottom of the timing diagram ('Capt aux bool').

[0097] The driver initiates the gear change maneuver by placing his foot under the control lever and exerting an upward force.

[0098] At time ta, the auxiliary sensor 7 or 7' detects a rotational movement of the external control lever or the first connecting rod 4L. The on / off signal 71 from the auxiliary sensor transitions to a second logic level, the inverse of the first. In the case of a variant of an analog auxiliary sensor, the value exceeds the first threshold, denoted SL.

[0099] This change triggers the motor torque reduction step (transition 62 at time ta, OFF to ON for torque reduction).

[0100] For reasons of conciseness of the presentation, the output, here boolean, of reduction of the couple, i.e. ON or OFF, is represented at mid-height and in the middle of the chronogram.

[0101] At time te, the user has brought their foot down and the external control lever has returned to its rest position, while the gear change on the selector shaft side is being completed. The transition back to the OFF state of the auxiliary information delivered by the auxiliary sensor may be later, as shown by the falling edges in dashed lines.

[0102] Advantageously, a step is provided for restoring the motor torque, where the reduction of the motor torque is removed, and the required motor torque is applied (transition 66 at time td).

[0103] In a particular embodiment, an internal counter is provided which counts the number of sampled occurrences of exceeding the first threshold predetermined by the auxiliary information, and a torque reduction is triggered if the internal counter exceeds a second predetermined threshold.

[0104] The second predetermined threshold is an integer, for example 3, 4 or 5

[0105] If the acquisition frequency of the auxiliary sensor is 1000 hertz, with an acquisition every 1 millisecond, and if the second threshold is 5, the triggering of the torque reduction takes place after 5 ms.

[0106] This makes it possible to strengthen the process without introducing too much delay.

[0107] The counter is intended to either be counted down or reset to zero when subsequent sampled values ​​of the auxiliary information fall below the first threshold. The counting and recounting can be symmetrical or asymmetrical.

[0108] Fig. 6 illustrates a scenario where the auxiliary sensor is of the analog type and the auxiliary information is not all or nothing but continuously represents the image of the movement of the external control lever or of another element of the control mechanism 9.

[0109] At time ta, the auxiliary sensor 7 or 7' detects a rotational movement of the external control lever or the first connecting rod 4L. The signal 71 exhibits a significant time ramp 72. The signal from the auxiliary sensor 7 is shown at the bottom of the timing diagram ('Capt aux analog').

[0110] The decision criterion for validating a torque reduction condition can be based on exceeding a level or threshold, or preferably on a ramp slope greater than a reference ramp slope. The reference ramp slope is configurable or calibrable. In one example, this threshold could be on the order of 1 Volt / 100 ms.

[0111] It is noted that the counting process described above for the case of auxiliary information can also be applied to the calculated rate of change of auxiliary information.

[0112] In addition, a confirmation of motor torque cut-off is provided if the current voltage value 61 acquired on the main sensor 2 becomes greater than a third predetermined threshold denoted VS1. This occurs at time tb.

[0113] The third predetermined threshold VS 1 exceeds the first reference value V1 by a first predetermined deviation noted El.

[0114] Expressed in other words, early detection by the auxiliary sensor is confirmed by the detection of the rotation of the selection shaft.

[0115] It is noted that the selection tree is indexed to the particular positions of the ratios and therefore it is not subject to vibrations or hazards as the auxiliary sensor may be in contrast.

[0116] Thus, confirmation by counting is mainly intended for the auxiliary sensor.

[0117] However, confirmation by counting can also be implemented for sampling the values ​​61 of the main sensor.

[0118] At time te, the auxiliary information 71 returns to its reference position. At time td, when the current voltage value 61 increases further, the motor torque reduction is removed, and the required motor torque is applied (transition 66 at time td).

[0119] At time tf, the voltage 61 is established at the second reference value V2 and the selection shaft 1 is indexed to the position of the arrival ratio, here the third ratio R3.

[0120] Regarding the deviations, we can choose for example that the first deviation El is between 5% and 15% of the difference between the second reference value V2 and the first reference value VI.

[0121] It should be noted that the first, second, third, fourth and fifth ratio tensions (VR1, VR2, VR3, VR4, VR5) are derived from a calibration table. They can be adjusted by learning, in relation to the indexing of the ratio positions as explained above.

[0122] With reference to [Fig.5], where only auxiliary information is used to trigger the reduction of engine torque, the auxiliary information could be analog, similar to that shown in [Fig.6], and a person skilled in the art could apply mutatis mutandis the case of analog auxiliary information to the scenario of [Fig.5].

[0123] Conversely, with reference to [Fig. 6], where the early auxiliary information is confirmed by the information delivered by the main sensor, the auxiliary information could be of an all-or-nothing nature, and the person in the trade could apply mutatis mutandis the case of all-or-nothing auxiliary information to the scenario of [Fig.6].

[0124] With reference to [Fig.7], the four cases of establishing the CRC reduction / cut-off condition of the motor torque have been illustrated.

[0125] More specifically, we have illustrated a step in determining a detection condition that leads to a reduction in engine torque. As discussed above, this reduction in engine torque facilitates a gear change to a higher gear.

[0126] The branch shown on the left, C2, indicates that the CRC torque cut-off condition can be obtained from the main sensor 2 alone. This can occur, for example, when the auxiliary sensor 7 is not operating or is temporarily unavailable. The detection condition is then based solely on the main sensor 2.

[0127] The branch shown in box C7 indicates that the torque cut-off condition can only be obtained from the auxiliary sensor 7, as explained in relation to [Fig. 5]. As a reminder, there may or may not be a counting mechanism in the processing of the information acquired from the auxiliary sensor.

[0128] The branch shown in box marked C27 indicates that the torque cut-off condition CRC can be obtained mainly from the main sensor 2 and confirmed by the information delivered by the auxiliary sensor 7. Conversely, the branch shown in box marked C72 indicates that the torque cut-off condition can be obtained mainly from the auxiliary sensor 7 and confirmed by the information delivered by the main sensor 2 as has been shown in relation to [Fig.6].

[0129] The momentary cut-off of engine torque can be achieved, for a certain number of engine cycles, by inhibiting the ignition control and canceling the fuel injection control.

Claims

Demands

1. A detection method for managing an upshift in a gearbox of a mobile machine having an engine, the shift being intended to change from a starting gear to an ending gear, in which the gearbox includes a selector shaft (1) movable between a first stable position (01) corresponding to the starting gear and a second stable position (02) corresponding to the ending gear, the gearbox including a main sensor (2) delivering a voltage value (61) corresponding to a current angular position of the selector shaft, the gearbox including a gear shift control mechanism (9) including an external control lever (3) and a linkage mechanism (4) connecting the external control lever to the selector shaft (1),The gearbox comprising an auxiliary sensor (7) capable of detecting a force or movement of at least one part of the control mechanism, the method comprising: - an acquisition step in which the voltage value (61) corresponding to the angular position of the selector shaft is iteratively acquired by means of the main sensor, and at least one auxiliary information (71) delivered by the auxiliary sensor is iteratively acquired, - a step of determining a condition for reducing engine torque, the condition for reducing torque being determined according to the information delivered by the auxiliary sensor (7) and / or by the main sensor (2).

2. Method according to claim 1, characterized in that a torque reduction condition occurs if the auxiliary information (71) exceeds a first predetermined threshold (SI).

3. Method according to claim 1, characterized in that a torque reduction condition occurs if the auxiliary information (71) has a time variation greater than a first time ramp (72).

4. A method according to claim 2, characterized in that it provides a first internal counter which counts the number of sampled occurrences of exceeding the first predetermined threshold by the auxiliary information, and the torque reduction condition is established if the first internal counter exceeds a second configurable threshold.

5. Method according to claim 1, characterized in that the torque reduction condition is established if the auxiliary information delivered by the auxiliary sensor exceeds a predetermined threshold, and if the current voltage value (61) acquired on the main sensor (2) becomes greater than a third predetermined threshold (VS1).

6. Calculator configured to implement the method according to any one of claims 1 to 5.

7. Product computer program, preferably stored on a non-transient memory medium, comprising instructions which, when executed by at least one processor of the computer, carry out the method according to any one of claims 1 to 5.

8. A control system for managing an upshift in a gearbox of a mobile machine having an engine, the shift being intended to change from a starting gear to an ending gear, the gearbox comprising a selector shaft (1) movable between a first stable position (01) corresponding to the starting gear and a second stable position (02) corresponding to the ending gear, the gearbox comprising a main sensor (2) delivering a voltage value corresponding to a current angular position of the selector shaft, the gearbox comprising a gear shift control mechanism (9) comprising an external control lever (3) and a linkage mechanism (4) connecting the external control lever (3) to the selector shaft (1), characterized in that the gearbox comprises an auxiliary sensor (7,7') capable of detecting an effort or movement of at least one part of the control mechanism, the control system comprising a computer (5) configured to acquire information from the main sensor (2) and the auxiliary sensor (7,7'), so as to be able to detect an effort exerted by a driver's foot on the external control lever, in order to proceed, if a torque reduction condition occurs, in an anticipated manner to a reduction of engine torque.

9. Control system according to claim 8, characterized in that the auxiliary sensor (7,7') is mounted at the axis (AXO) of the external control lever (3) and the auxiliary sensor is of the potentiometric analog type and delivers angular information.

10. Control system according to claim 8, characterized in that the auxiliary sensor (7,7') is mounted opposite a connecting rod (41,42) of the linkage mechanism (4).

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