Method for controlling gear shifting of bicycle
Patent Information
- Application Number
- JP2024113869
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2023-07-24
- Filing Date
- 2024-07-17
- Publication Date
- 2025-02-19
Smart Images
Figure 2025023894000001_ABST
Abstract
Description
[Technical field]
[0001] The present invention relates to a method for controlling gear shifting on a bicycle, to a bicycle shifting system and to a bicycle. [Background technology]
[0002] Bicycle shifting systems are known that are designed to be electronically operable, which allows the possibility of providing automatic operation of gear changes. To activate such automatically operated gear changes, for example, certain shift thresholds are provided. Such shift thresholds can be stored in the form of a table in the memory of a control device of the shifting system. In the case of automatic shifting for bicycles, a conflict of objectives often arises between providing an optimal shift for the cyclist in order to provide the best possible pedaling comfort and avoiding unnecessarily frequent gear changes. Summary of the Invention
[0003] In contrast, the method according to the invention with the features of claim 1 offers the advantage that automatic gear changing of a bicycle gear shift can be easily enabled and in this case a particularly high level of pedal comfort can be ensured for the bicycle driver. This is because, according to the invention, a method for controlling a bicycle gear shift comprises: - detecting a reference shift point; - detecting a current riding condition of the bicycle; - determining a shift hysteresis based on the detected current driving conditions; - detecting a target shift point by adjusting the reference shift point using the determined shift hysteresis; This is achieved by a method comprising:
[0004] That is, the method determines a characteristic reference shift threshold in the form of a reference shift point, and adaptively adjusts this, in particular by means of a variable shift hysteresis, to determine an actual shift threshold in the form of a target shift point.
[0005] In this case, a number of possible driving conditions may be detected as the driving conditions and used to modify the shift hysteresis, for example, the detection of a gradient or a predetermined operation manner by the bicycle driver may also be identified as the driving conditions and the shift hysteresis may be adjusted accordingly.
[0006] In particular, a certain change amount is regarded as the shift hysteresis, and the reference shift point is displaced toward the target shift point by this change amount. For example, the shift hysteresis can be regarded as a pedal stroke amount. Alternatively, the shift hysteresis can be preferably defined by a further physical quantity, in particular the reference shift point being defined as a function of this further physical quantity.
[0007] Preferably, the shift hysteresis may be specified as a particular constant value that displaces, for example, a reference shift point toward a target shift point by the particular constant value. Alternatively, the shift hysteresis may be advantageously specified as a particular percentage deviation relative to a reference shift point.
[0008] Preferably, in the case of gear shifts with several different gears, i.e. several different transmission ratios, a separate reference shift point is determined for each gear. The reference number of strokes is preferably equal for all gears. Alternatively, different reference numbers of strokes can be defined for different gears.
[0009] The method therefore offers the advantage that an optimal shift strategy can be provided by adjusting the adaptive shift hysteresis depending on the current driving operation of the bicycle. As reference number of strokes, for example, an individual desired number of strokes of the bicycle driver can be used. This allows, for example, the method to optimally adjust the shift strategy, for example, to a specific number of strokes, in which case the number of gear changes can be reduced by adaptive adjustment of the shift hysteresis. In particular, the adaptive adjustment of the shift hysteresis can achieve optimal conditions based on the most accurate possible adjustment to predefined characteristic values and / or the fewest possible number of gear changes. In particular, the method can therefore enable a particularly efficient and comfortable operation of the bicycle.
[0010] The dependent claims contain advantageous further configurations of the invention.
[0011] Advantageously, the reference shift point is determined in such a way that, when a gear change is made at the reference shift point, the step jump caused by the gear change is symmetrical with respect to the reference step number, i.e., a characteristic shift threshold value is determined in the form of a reference shift point. If a shift process is performed at this reference shift point, i.e., if a gear change is performed, in particular if a gear change is performed to the next gear step, this gear change will result in a specific step jump. In this case, preferably based on the known mechanical properties of the gear change and preferably additionally based on the known mechanical properties of the drive of the bicycle, the reference shift point is automatically determined in such a way that the corresponding step jump at this reference shift point is symmetrical with respect to the reference step number. In particular, the step jump is determined to be the difference value of the respective step number before and after the gear change. In particular, the step jump is determined to be the theoretical change in the step number which occurs before, during and after the gear change in the case of pedaling, in particular under tension in the drive system of the bicycle. Such a step jump is precisely defined, for example, on the basis of the mechanical relationship between the shifting system of the bicycle and the entire power train. In other words, the reference shift point is defined such that, for example, during an upshift to a larger gear ratio, the step number immediately before the gear change is greater than the reference step number by a predefined value. At the same time, the step number immediately after the gear change is less than the reference step number by the same predefined value. For example, during a downshift to a smaller gear ratio, the step number change is correspondingly exactly the opposite.
[0012] Advantageously, the reference number of strokes is a predefined constant value. Alternatively, and preferably, the reference number of strokes is a constant value that can be preset by the user. As a further alternative, and preferably, the reference number of strokes is variably configured and can be set in dependence on one or several of the following parameters: the current gear, the bicycle's travel parameters, the environmental parameters. In particular, these parameters can be detected on the basis of sensors and / or can be entered by means of an input device. For example, the bicycle's speed and / or inclination and / or acceleration can be used as travel parameters. For example, the current gradient that the bicycle is taking up and / or the section parameters of the section to be traveled, such as the curves to be traveled, can be used as environmental parameters. This allows a particularly flexible and precise adaptation of the shift strategy to the bicycle's travel behavior and / or to the individual preferences of the user.
[0013] Particularly advantageously, a reduction in the shift hysteresis is performed in the first driving situation in order to reduce, in particular minimize, the deviation between the actual number of strokes and the reference number of strokes. In particular, the current actual number of strokes at which the bicycle driver is pedaling is regarded as the actual number of strokes. In other words, in the first driving situation, a small hysteresis is used to generate an adjustment to the reference number as precisely as possible. Alternatively or additionally, advantageously, an increase in the shift hysteresis is performed in the second driving situation in order to reduce, in particular minimize, the number of gear changes, in particular while the second driving situation continues. In other words, in the second driving situation, a large hysteresis is used so that fewer shift operations are performed.
[0014] Advantageously, a target upshift point and a target downshift point are determined for each reference shift point by means of a shift hysteresis. In particular, for this purpose, the reference shift points are displaced in opposite directions by the shift hysteresis. Preferably, a shift point leading to a larger gear, i.e. to a larger transmission ratio, is regarded as the target upshift point. More preferably, a shift point leading to a smaller gear, i.e. to a smaller transmission ratio, is regarded as the target downshift point. This makes it possible to provide a particularly reliable and efficient automatic shifting method, which allows for the avoidance of undesirably frequent gear changes.
[0015] Preferably, the target downshift point is defined at a lower speed compared to the reference shift point, in particular with respect to the bicycle's riding operation. Alternatively or additionally, the target upshift point is defined at a higher speed compared to the reference shift point, in particular with respect to the bicycle's riding operation. This means, for example, that if the reference number of strokes is reached and the speed is reduced, which is therefore accompanied by a reduction in the number of strokes, then a shift is not made immediately, but only after a further reduction in speed has occurred and the target downshift point is reached. Preferably, an upshift is made in a similar manner if the speed increases. This allows for optimal efficiency and high riding comfort during bicycle operation.
[0016] Furthermore, preferably, the shift hysteresis for each reference shift point is equal for each target downshift point and target upshift point, in other words, the target downshift points and the target upshift points are arranged symmetrically with respect to the reference shift point with the same shift hysteresis. Alternatively, preferably, the shift hysteresis for each reference shift point is different for each target downshift point and target upshift point, in other words, the target downshift points and the target upshift points are arranged asymmetrically with respect to the reference shift point with different shift hysteresis.
[0017] Particularly advantageously, the shift hysteresis is variably adjusted depending on one or several of the following parameters: the current gear, the bicycle's driving parameters, the environmental parameters, the user's individual input. In particular, these parameters can be detected on the basis of sensors and / or can be entered by means of an input device. For example, the bicycle's speed and / or inclination and / or acceleration can be used as the driving parameters. For example, the current gradient that the bicycle is taking up and / or section parameters of the section to be traveled, such as the curve to be traveled, can be used as the environmental parameters. This allows a particularly precise adaptation of the shift strategy to the bicycle's driving behavior to be made.
[0018] Particularly advantageously, the method includes the steps of detecting constant speed travel as the current driving situation and reducing the shift hysteresis in response to the detection of constant speed travel. Preferably, a bicycle ride with a substantially constant speed over at least one predefined time period is considered to be constant speed travel. For example, a bicycle ride is considered to be constant speed travel if the maximum variation in the bicycle speed is 15%, advantageously 10%, in particular 5%, over a time period of, for example, at least 10 seconds, in particular at least 30 seconds. Preferably, in response to the detection of constant speed travel, the shift hysteresis is determined such that the shift hysteresis has a percentage deviation of at most 10%, advantageously at most 7%, in particular at most 5%, with respect to the reference shift point. In the case of stationary travel with a substantially constant driving speed over a relatively long time period, it is thus possible to adjust the driver's desired number of strokes, which may for example correspond to the reference number of strokes, as best as possible.
[0019] Furthermore, the method preferably includes the steps of detecting a pedaling interruption as the current driving situation and increasing the shift hysteresis in response to the detection of the pedaling interruption. Preferably, the pedaling interruption corresponds to the second driving situation. Particularly preferably, the increase in the shift hysteresis in response to the detection of the pedaling interruption can be performed only for the target downshift point, while the shift hysteresis for the target upshift point is advantageously maintained. Preferably, a pedaling interruption is considered to be a cessation of pedaling by the driver for at least one predefined time period, for example at least 2 seconds, advantageously at most 10 seconds. Alternatively, a pedaling interruption can preferably be considered to be a state in which the bicycle driver generally does not apply a pedaling torque to the bicycle powertrain, in which case it is also possible, for example, to further rotate the pedals tension-free without power transmission to the powertrain. Preferably, the shift hysteresis is determined in response to the detection of a pedal interruption such that the shift hysteresis has a percentage deviation of at least 10%, preferably at least 13%, in particular at least 15% with respect to the reference shift point. Such pedal interruptions can occur, for example, when driving around curves. In this case, for example, the shift hysteresis can be increased for a short time to prevent an immediate backshift to a smaller gear upon pedal interruption. This can, for example, prevent the driver from having to immediately repeat a previous gear change after the driver resumes pedal operation, i.e., undesirable back-and-forth shifts can be avoided.
[0020] Further advantageously, the method includes the steps of detecting mountain road travel as the current riding situation and increasing the shift hysteresis in response to the detection of mountain road travel. Preferably, mountain road travel corresponds to the second riding situation. Preferably, riding the bicycle uphill in a mountain road is considered as mountain road travel, where the uphill road advantageously corresponds to a gradient of at least 5% with respect to the horizontal line. Preferably, in response to the detection of mountain road travel, the shift hysteresis is determined such that the shift hysteresis has a percentage deviation of at least 10%, advantageously at least 13%, in particular at least 15% with respect to a reference shift point. Such an increase in shift hysteresis in mountain road travel is advantageous in particular in electric bicycles. For example, when the riding speed of the electric bicycle decreases due to a small motor power, a smaller gear is shifted. In particular in the case of electric bicycles in which the motor is arranged in the region of the crankshaft, the gear change causes the motor speed to increase again in a smaller gear, which in turn makes it possible, for example, to provide more motor power again and thus to accelerate the electric bicycle, so that, for example, it is possible to shift again to a larger gear. Thus, by increasing the shift hysteresis, undesirable frequent back and forth shifts are efficiently avoided in a simple manner.
[0021] Advantageously, the method comprises the steps of detecting an acceleration run as the current riding situation and decreasing the shift hysteresis for the target upshift point, in particular to a value of zero. Advantageously, the shift hysteresis for the target downshift point is kept constant or, alternatively, advantageously increased. Preferably, the acceleration run corresponds in particular at least partially to the first riding situation. Preferably, a bicycle run with positive acceleration, i.e. a run in which the speed increases significantly, is considered as an acceleration run. In particular when several gear changes are made one after the other during an acceleration run, this allows for a particularly efficient acceleration of the bicycle, since this allows for an optimal number of steps. For example, a small shift hysteresis for the target upshift point, preferably a zero shift hysteresis, allows for an immediate and purposeful upshift, which avoids pedaling faster than would be optimal, for example, during an acceleration process.
[0022] Preferably, the method further comprises the step of determining a shift speed at the target shift point based on the transmission ratio of the bicycle. In particular, the speed at which the bicycle moves forward, for example theoretically, at the target shift point is considered as the shift speed. This shift speed is predefined, in particular depending on the corresponding gear, by the mechanical relationship between the number of strokes, in particular the theoretical number of strokes, at the target shift point and the transmission ratio of the bicycle. In so doing, the entire transmission ratio is taken into account, for example the entire transmission ratio between the crank and the rear wheel of the bicycle. This allows a particularly simple detection of the favorable shift point.
[0023] Advantageously, the shift speed can be determined at any time, for example when the bicycle is stopped and / or before the first start, whereby the shift speed can be stored, for example, as a characteristic value for the shift system.
[0024] Furthermore, the method preferably includes the steps of detecting the speed of the bicycle, in particular the current speed, and initiating the gear change when the detected speed reaches a shift speed, i.e. the method includes initiating the shift process as a function of the detected speed at which the bicycle moves forward. This allows the method to be implemented in a particularly simple and cost-effective manner and provides a particularly advantageous shift strategy, since the shift strategy cannot depend on the actual number of pedal strokes currently performed by the driver, for example, when pedaling down a mountain road. If no pedaling is performed, for example when driving down a mountain road, the optimal shift point can be determined as a function of the speed, so that the optimal gear can be engaged when pedaling is resumed, for example.
[0025] Preferably, the method comprises the steps of detecting the number of shift strokes at the target shift point, detecting the number of strokes, in particular the current number of strokes, and initiating a gear change when the detected number of strokes reaches the shift stroke number, i.e. initiating the shift process as a function of the detected number of strokes at which the driver operates the pedal of the bicycle, thereby providing a particularly precise control of the shift process in order to optimally adjust the advantageous number of strokes.
[0026] Particularly preferably, the bicycle gear shift has a number of different gears, and a separate reference shift point is determined for each gear change between the different gears, i.e. a shift point is determined separately for each of the gears, so that the shift strategy can be adjusted particularly precisely, thereby providing the bicycle driver with optimal driving comfort.
[0027] Furthermore, the present invention relates to a shifting system for a bicycle, preferably an electric bicycle, comprising a gearshift and a control unit, the control unit being arranged for operating the gearshift and carrying out the aforementioned method. Preferably, the gearshift comprises a derailleur arranged for varying the transmission ratio by shifting the bicycle chain between rear sprockets of different sizes. Alternatively or additionally, the gearshift may advantageously comprise a transmission shift. Particularly preferably, the gearshift comprises an electronic operating device, in which case the control unit is arranged in particular for operating the electronic operating device of the gearshift.
[0028] Furthermore, the present invention relates to a bicycle, preferably an electric bicycle, including the above-mentioned shifting system.
[0029] The invention will now be explained by way of example only with reference to the drawings, in which functionally identical components are each provided with the same reference numerals. [Brief description of the drawings]
[0030] [Figure 1] 1 is a simplified schematic diagram of a bicycle in which a method for controlling bicycle gear shifting according to a first embodiment of the present invention is implemented; [Diagram 2] FIG. 2 is a highly simplified schematic diagram of the method steps of the first embodiment; [Diagram 3] FIG. 2 is a simplified schematic diagram of a shift process when implementing the method of the first embodiment. [Figure 4] FIG. 6 is a simplified schematic diagram of a shifting process when implementing a method according to a second embodiment of the present invention. [Diagram 5] FIG. 4 is a highly simplified schematic diagram of the steps of a method according to a third embodiment of the present invention; [Figure 6] FIG. 13 is a simplified schematic diagram of a shift process when implementing the method of the third embodiment. [Figure 7] FIG. 11 is a simplified schematic diagram of a shifting process when implementing a method according to a fourth embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0031] 1 is a simplified schematic diagram of a bicycle 100 with a shifting system 107 including a gear shift 105 and a control unit 106. The gear shift 105 is a derailleur that includes a front derailleur and at least a number of different sized rear sprockets mounted on the rear wheel hub of the bicycle 100.
[0032] Gear shift 105 has an electronic operating device that, in response to receiving an electronic operating signal, effects a gear change, i.e., a change in transmission ratio, in a powertrain of bicycle 100. The electronic operating signal may be generated by control unit 106. In particular, automatic shifting of bicycle 100 may thereby be provided.
[0033] The bicycle 100 includes a drive unit 101, in particular an electric bicycle including a drive unit 101 with an electric motor. Preferably, the control unit 106 is integrated in the drive unit 101. The drive unit 101 can be supplied with electric energy by means of an electric energy accumulator 109 of the bicycle 100. In this case, the drive unit 101 can assist the pedaling force generated by the muscle force of the driver of the bicycle 100 with a motor torque generated by the electric motor.
[0034] The control unit 106 is thereby arranged to carry out a method 50 for controlling, in particular automatically, a gear shift 105 of the bicycle 100. The method steps of the method 50 are illustrated in a very simplified schematic diagram in Fig. 2. The details of the shifting process will be explained in more detail later. For the moment, a very simplified general description of the method 50 will be given.
[0035] In the method 50, in step 51, a reference shift point 1 is detected, and a target upshift point 31 and a target downshift point 32 are detected based on the reference shift point 1.
[0036] At target upshift point 31, an upshift to the next larger gear preferably occurs as speed 22 of bicycle 100 increases. At target downshift point 32, a downshift to the next smaller gear preferably occurs as speed 22 of bicycle 100 decreases.
[0037] Similarly, at step 51, for each target upshift point 31 and target downshift point 32, the shift speed 30 at which the corresponding shift point exists can be determined.
[0038] The method 50 includes, in step 52, sensing the current speed 22 of the bicycle 100. In step 53, if the sensed current speed 22 reaches one of the plurality of shift speeds 30, initiation of a gear change is performed.
[0039] A detailed description of the shift points follows, with the first embodiment of the method 50 according to figures 1 to 3 showing a particularly simple embodiment variant of the method 50. The second to fourth embodiment examples of the method 50 show further variants.
[0040] The shift points and gear changes described below are described as examples based on gear changes between the two highest gears, i.e. between the two highest transmission ratios, and in particular what is described below applies equally to all other gears of the gear shift 105.
[0041] In Fig. 3, a simplified schematic diagram of a shifting process when implementing the method 50 according to the first embodiment is shown. Fig. 3 shows a so-called display diagram 20 of the drive system of the bicycle 100. The display diagram 20 shows the relationship between the number of strokes 21 and the speed 22 for each of the gear stages of the gear shift 105. Straight lines 23 represent the different gear stages of the gear shift 105. These straight lines 23 are each clearly defined by the mechanical properties of the drive system of the bicycle 100, in particular the mechanical properties of the mechanical transmission paths between the pedals 104 and the rear wheel 111 of the bicycle 100. In particular, the gradient of each of the straight lines 23 depends on the respective gear ratio of each gear stage.
[0042] In this regard, a straight line 23 with a smaller gradient, i.e. a straight line 23 moving downwards and to the right in the representation diagram 20, represents a higher gear with a larger transmission ratio.
[0043] In the case of the method 50, a reference step number 3 is defined, and the reference step number is, for example, a constant value that is set in advance. For example, the reference step number 3 can be set in advance by the driver of the bicycle 100.
[0044] During operation of bicycle 100, in particular each operating point of shifting system 107 lies on operating line 26 as shown in Fig. 3. In this case, operating line 26 is always on one of straight lines 23 and, during a gear change, is changed to the respectively adjacent straight line 23 by a jump, which is shown vertically in Fig. 3.
[0045] In the first embodiment, the reference shift point 1 is determined in such a way that, when a gear change is performed at the reference shift point 1, a step jump 2 caused by this gear change is symmetrical with respect to the reference step jump 3. In this case, the step jump 2 corresponds to the value of the step difference in the display diagram 20, i.e. corresponds to the vertical distance between the current straight line 23 and the adjacent straight line 23 which makes a jump due to the gear change.
[0046] In other words, the reference shift point 1 is selected so that exactly at the reference shift point 1, the partial amount 29a between the reference number of strokes 3 and the respective number of strokes 21 in the gear stage is equal before or after the gear change.
[0047] In the first embodiment, the reference shift point 1 thus detected also simultaneously corresponds to a target upshift point 31 and a target downshift point 32 at which an upshift or downshift actually begins.
[0048] Due to the correspondingly defined reference shift point 1, which in the first embodiment also corresponds to the actual target shift point, a speed range 27 for each gear can be read off from the display diagram 20 using the correspondingly set operating line 26 as a range between two adjacent vertical pedal stroke jumps, as illustrated by way of example for 8th gear in FIG. 3.
[0049] Furthermore, in the method 50, a shift speed 30 is detected for each target shift point 31, 32, and is, for example, stored. Initiation of a gear change during operation of the method 50 is then performed, preferably exclusively speed-dependent, i.e., when the current speed of the bicycle 100 increases and reaches the shift speed 30 for one of the multiple gears, a gear change to the next higher gear is initiated. Similarly, when the current speed of the bicycle 100 decreases and reaches the shift speed 30 for one of the multiple gears, a gear change to the next smaller gear is initiated.
[0050] In this case, the determination of all shift points 1, 31, 32 can advantageously be carried out once by means of the control unit 106, for example before starting the bicycle 100. Preferably, the respective shift speeds 30 can be stored for all shift points 1, 31, 32.
[0051] It would then be particularly advantageous if all gear changes could be initiated while the bicycle 100 is in operation, in particular solely on the basis of the current gear and the shift speed 30. This would allow for an efficient and comfortable operation of the bicycle 100, by enabling a particularly simple and reliable and precise gear selection in each riding situation.
[0052] In an alternative embodiment, the gear change may be initiated based on the shift stroke count 39 detected at the target shift points 31, 32 and the current stroke count of the bicycle 100 may be sensed.
[0053] 4 is a simplified schematic diagram of a shifting process when implementing a method 50 according to a second embodiment of the present invention. The second embodiment substantially corresponds to the first embodiment of FIGS. 1 to 3, except that a shift hysteresis 4 is additionally provided for determining the actual target shift points 31, 32.
[0054] 4, a separate target upshift point 31 and a separate target downshift point 32 are defined for each reference shift point 1. The target upshift point 31 is defined by shifting the reference shift point 1 by the shift hysteresis 4 toward the higher speed 22. The target downshift point 32 is defined by shifting the reference shift point 1 by the shift hysteresis 4 toward the higher speed 22. Thus, an upshift takes place later when the speed 22 increases and at a higher speed 22 compared to the reference shift point 1, and a downshift takes place later when the speed 22 decreases and at a lower speed compared to the reference shift point 1. Thus, an upshift speed 41 different from the downshift speed 42 of the target downshift point 32 is obtained for the target upshift point 31.
[0055] This clearly results in relatively infrequent gear changes being initiated, for example during frequent speed changes close to the reference shift point 1. Thus, in particular, undesirable frequent back and forth shifts can be avoided.
[0056] In the second embodiment, the shift hysteresis 4 is defined as a certain percentage deviation that is predefined with respect to the reference shift point 1. More specifically, the shift hysteresis 4 corresponds to 5% of the speed value of the reference shift point 1.
[0057] As can be seen in FIG. 4, the shift hysteresis 4 results in relatively wide speed ranges 27 for the individual gears, these speed ranges 27 resulting from the shift hysteresis 4 partially overlapping (not shown).
[0058] 4, the shift hysteresis loops 4 are each symmetrically embodied with respect to the reference shift point 1. In an alternative embodiment, an asymmetric shift hysteresis loop 4 can also be provided, i.e., for each reference shift point 1, a different shift hysteresis loop 4 is used for determining the corresponding target upshift point 31 than for determining the corresponding target downshift point 32.
[0059] Figure 5 shows a highly simplified schematic diagram of the steps of a method 50 according to a third embodiment of the invention. The third embodiment substantially corresponds to the second embodiment of Figure 4, with the difference that the shift hysteresis 4 is made adjustable to suit the current riding behavior of the bicycle 100.
[0060] For this purpose, the method 50 includes additional steps 56 to 58 after the step 51 of detecting the reference shift point 1 and before step 52. In step 56, a detection of the current riding situation of the bicycle 100 is performed. In this case, the current riding situation is preferably detected and recognized by means of the sensor device 110 of the bicycle 100. Based on the thus detected riding situation, the current shift hysteresis 4 is then adaptively adjusted in step 57. Based on the adapted shift hysteresis 4, a detection of the target upshift point 31 and the target downshift point 32 is performed in step 58.
[0061] In this case, the adaptive adjustment of the shift hysteresis 4 can be made on the basis of the very different characteristic driving situations. In this case, it is preferably possible to determine, in general, whether the priority should be an optimal adjustment to the reference number of strokes 3 or, alternatively, a minimization of the number of gear changes should be prioritized on the basis of the recognized driving situation. For the first case, i.e. for the case where the deviation of the actual number of strokes from the reference number of strokes 3 is to be minimized as a priority, a low shift hysteresis 4 is set, in particular, for example, at most 10%. This corresponds, for example, to the display diagram 20 of FIG. 4. For the second case, i.e. for the case where the priority should be a minimization of the number of gear changes, a high shift hysteresis 4 is set, in particular, for example, at least 10%.
[0062] In the method 50, a predefined driving situation may be recognized and in response a predefined shift hysteresis 4 may be set. For example, as already mentioned, if constant speed driving is detected as the current driving situation, the method 50 according to Fig. 5 may be used to obtain the display diagram 20 of Fig. 4 by adaptive adjustment of the shift hysteresis 4. Constant speed driving may be recognized, for example, when a speed 22 that remains substantially constant is recognized. In that case, the shift hysteresis 4 may be reduced to a relatively low value of 5%, allowing an accurate adjustment to the reference number of strokes 3.
[0063] In addition, the method 50 of Fig. 5 can detect a step interruption as the current driving situation and / or detect mountain driving as the current driving situation, and in response thereto, an increase in the shift hysteresis 4, for example to at least 15%, can be performed. A corresponding display diagram 20 is shown in Fig. 6. As can be seen in Fig. 6, this results in a significantly wider speed range 27 for the individual gears, and thus also, for example, a significantly larger overlap of the individual gears. This makes it possible to reduce the total number of shift changes when driving the bicycle 100, which has an advantageous effect on the driving comfort for the driver in these driving situations.
[0064] Fig. 7 is a simplified schematic diagram of a shifting process when implementing a method 50 according to a fourth embodiment of the present invention. The fourth embodiment substantially corresponds to the third embodiment of Figs. 5 and 6, but may be considered as a further configuration of the method 50 of the third embodiment, in particular because it takes into account additional riding situations. The fourth embodiment of Fig. 7 provides an asymmetric adaptation of the shift hysteresis 4 in response to the recognition of an accelerating ride as the current riding situation of the bicycle 100.
[0065] In this example, the shift hysteresis 4 for the target upshift point 31 is set to a value of zero so that the target upshift point 31 corresponds to the reference shift point 1 .
[0066] At the same time, the shift hysteresis 4 relative to the target downshift point 32 is maintained or alternatively increased, for example to 15%, so that an optimal number of strokes can always be adjusted during acceleration of the bicycle 100 through several gears, in particular by always shifting close to the reference number of strokes 3. Thus, an optimized driving comfort can be provided to the driver of the bicycle 100 even in this riding situation.
[0067] It should be noted that the described embodiments may be combined with one another in any manner, for example, each of the described embodiments may be provided for a particular time range of riding operation of bicycle 100 and / or for a particular operating mode. [Explanation of symbols]
[0068] 1 Reference shift point 2. Number of steps jump 3. Standard number of steps 4 Shift Hysteresis 21 Steps 22 Bicycle Speed 30 Shift Speed 31 Target upshift point 32 Target downshift point 39 Shift count 50 ways 100 Bicycles 105 Gear shift 106 Control Unit 107 Shift System 110 Sensor device
Claims
1. A method for controlling a gear shift (105) of a bicycle (100) comprising the steps of: - detecting a reference shift point (1); - detecting the current riding conditions of said bicycle (100); - determining a shift hysteresis (4) based on the detected current driving situation; - detecting a target shift point (31, 32) by adjusting the reference shift point (1) using the determined shift hysteresis (4); A method comprising:
2. 2. The method according to claim 1, wherein the reference shift point (1) is detected such that, when a gear change is made at the reference shift point (1), a step jump (2) caused by the gear change is symmetrical with respect to a reference step number (3).
3. A reduction in the shift hysteresis (4) is performed in a first driving situation in order to reduce the deviation between the actual pedal stroke and the reference pedal stroke (3), and / or Increasing the shift hysteresis (4) in a second driving situation in order to reduce the number of gear changes. The method of claim 2.
4. 4. The method according to claim 1, further comprising detecting a target upshift point (31) and a target downshift point (32) for each reference shift point (1) by adjusting the reference shift point (1) using the shift hysteresis (4).
5. 5. The method of claim 4, wherein the target downshift point (32) occurs when the speed (22) is smaller than the reference shift point (1) and / or the target upshift point (31) occurs when the speed (22) is greater than the reference shift point (1).
6. 6. The method according to claim 4 or 5, wherein the shift hysteresis (4) for each reference shift point (1) is determined to be equal or different for each of the target downshift points (32) and the target upshift points (31).
7. Each of the following steps: - detecting constant speed driving as a current driving situation; - decreasing said shift hysteresis (4) in response to said detection of constant speed travel; The method according to any one of claims 1 to 6, comprising:
8. Each of the following steps: - detecting a pedal interruption as a current driving situation; - increasing said shift hysteresis (4) in response to detection of said pedal interruption; The method according to any one of claims 1 to 7, comprising:
9. Each of the following steps: - detecting mountain road driving as a current driving situation; - increasing said shift hysteresis (4) in response to said detection of mountain driving; The method according to any one of claims 1 to 8, comprising:
10. Each of the following steps: - detecting acceleration as a current driving situation; - decreasing said shift hysteresis (4) for said target upshift point (31), in particular decreasing it to a value of zero; The method according to any one of claims 4 to 9, comprising:
11. The method according to any one of claims 1 to 10, wherein the detection of the current riding condition of the bicycle (100) is performed using sensor data of a sensor device (110) of the bicycle (100), in particular the sensor data including one or several of the following sensor data: inclination, acceleration, speed, pedal torque, and pedal count.
12. Each of the following steps: - detecting a shift speed (30) at said target shift points (31, 32) based on a gear ratio of said bicycle (100); - detecting a speed (22); - initiating a gear change when said detected speed (22) reaches said shift speed (30); The method according to any one of claims 1 to 11, comprising:
13. The method according to any one of claims 1 to 12, wherein the gear shift (105) of the bicycle (100) has a plurality of gears and a separate target shift point (31, 32) is detected for each gear change between all gears.
14. A shifting system for a bicycle (100) comprising a gearshift (105) and a control unit (106) arranged to operate said gearshift (105), said control unit (106) being arranged to carry out a method (50) according to any one of claims 1 to 13.
15. A bicycle, in particular an electric bicycle, including a shifting system (107) according to claim 14.