Bicycle braking system

Abstract

Bicycle braking system (10; 210), comprising: an operating device (12) comprising an operating element (16) adapted to be operated by a user; a braking device (14) configured to exert a braking force on a movable element (M1) of a bicycle in response to an operation of the operating element (16), wherein the braking device (14) comprises at least one friction element (18, 20) configured to come into contact with the movable element (M1); a sensor device (22) which is designed first information regarding an operation amount of the operating element (16) and to measure second information relating to an operating force of the operating element (16); and an adjusting device (24) configured to adjust a position of the at least one friction element (18, 20) based on the first information and the second information, wherein the adjusting device (24) is designed to adjust a clearance (C1) between the movable element (M1) and the at least one friction element (18, 20) based on the first information and the second information.

Description

[0001] The present invention relates to a bicycle braking system.

[0002] Cycling is becoming an increasingly popular form of recreation as well as a mode of transportation. Furthermore, cycling has become a very popular competitive sport for both amateurs and professionals. Whether the bicycle is used for recreation, transportation, or competition, the bicycle industry is constantly improving the various components of the bicycle. One bicycle component that has recently undergone extensive redesign is the braking system.

[0003] The braking system includes an operating device and a braking device. The braking device includes a friction element for exerting a braking force on a sliding element, such as a wheel or a disc brake rotor. The friction element wears due to sliding with the sliding element.

[0004] Conventional bicycle brake systems are known, for example, from US 2008 / 0 111 342 A1, DE 10 2010 038 525 A1, DE 44 39 016 A1, and DE 101 58 382 A1. DE 10 2010 038 525 A1 discloses a bicycle brake system comprising an operating device, a braking device, and a sensor device. The operating device comprises an operating element configured to be operated by a user. The braking device is configured to exert a braking force on a movable element of a bicycle in response to an operation of the operating element. The braking device comprises at least one friction element configured to come into contact with the movable element. The sensor device is configured as a rotation rate or speed sensor to determine an angular velocity of the front wheel or rear wheel.

[0005] The object of the invention is to propose a bicycle brake system with which it is possible to ensure a rapid reaction of the bicycle brake system during braking, even with increasing wear of the at least one friction element.

[0006] To achieve this object, a bicycle braking system according to claim 1 is proposed. According to the present invention, a bicycle braking system comprises an operating device, a braking device, a sensor device, and an adjusting device. The operating device comprises an operating element configured to be operated by a user. The braking device is configured to exert a braking force on a movable element of a bicycle in response to an operation of the operating element. The braking device comprises at least one friction element configured to come into contact with the movable element. The sensor device is configured to measure first information regarding an operation amount of the operating element and second information regarding an operation force of the operating element.The adjustment device is configured to adjust a position of the at least one friction element based on the first information and the second information. Furthermore, the adjustment device is configured to adjust a clearance between the movable element and the at least one friction element based on the first information and the second information.

[0007] Advantageous embodiments are the subject of dependent claims 2 to 14.

[0008] In a preferred embodiment, the adjustment device comprises an actuating device and an adjustment control device. The actuating device is configured to actuate the braking device to move the at least one friction element. The adjustment control device is configured to control the actuating device to move the at least one friction element based on the first information and the second information.

[0009] In a preferred embodiment, the braking device comprises a transmission element configured to transmit the operating force from the operating element to the at least one friction element. The at least one friction element is movable from a rest position toward the movable element in response to the operating force transmitted by the transmission element. The actuating device is configured to move the transmission element to change the rest position of the at least one friction element.

[0010] In a preferred embodiment, the braking device comprises a secondary cylinder and a secondary piston movably provided in the secondary cylinder. The transmission element is coupled to the secondary piston to move together with the secondary piston relative to the secondary cylinder.

[0011] In a preferred embodiment, the adjustment control device comprises a clearance value detection part configured to detect a comparison value relating to a clearance between the at least one friction element and the movable element based on the first information and the second information.

[0012] In a preferred embodiment, the adjustment control device is configured to compare the comparison value with a reference value. The adjustment control device is configured to control the actuating device to move the at least one friction element based on a comparison between the comparison value and the reference value.

[0013] In a preferred embodiment, the adjustment control device is configured to store the first to N1-th most recent comparison values, where N1 is an integer greater than or equal to 2. The adjustment control device is configured to calculate an average value of the first to N1-th most recent comparison values as the comparison value. The adjustment control device is configured to control the actuating device to adjust the clearance between the at least one friction element and the movable element in a case where the comparison value is greater than the reference value by a reference difference value or more.

[0014] In a preferred embodiment, the adjustment control device is configured to detect the reference value based on the first information and the second information in an adjustment mode.

[0015] In a preferred embodiment, the adjustment control device is configured to store the first to N2-th most recent comparison values in the adjustment mode, where N2 is an integer greater than or equal to 2. The adjustment control device is configured to calculate an average value of the first to N2-th most recent comparison values in the adjustment mode as a reference value.

[0016] In a preferred embodiment, the operating device comprises a main body configured to pivotally support the operating element. The sensor device comprises a first sensor configured to measure an operating angle of the operating element relative to the main body as the first piece of information.

[0017] In a preferred embodiment, the sensor device comprises a second sensor which is designed to measure, as the second information, an operating force exerted by the operating element on the braking device.

[0018] In another preferred embodiment of the present invention, the bicycle brake system further comprises a hydraulic hose configured to hydraulically couple the operating device to the braking device. The operating device comprises a master cylinder and a master piston. The master piston is movably provided in the master cylinder to define a master chamber configured to generate hydraulic pressure in response to an operation of the operating member as the operating force. The braking device comprises a secondary cylinder and a secondary piston. The secondary piston is movably provided in the secondary cylinder to define a secondary chamber configured to be connected to the master chamber via the hydraulic hose.

[0019] In a preferred embodiment, the bicycle brake system is designed such that the second sensor is designed to measure the hydraulic pressure as the second information.

[0020] In a preferred embodiment, the bicycle brake system is configured such that the braking device comprises, as the at least one friction element, a first friction element and a second friction element, which are configured to sandwich the movable element between the first friction element and the second friction element in order to exert the braking force on the movable element. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] A more complete appreciation of the invention and many of its attendant advantages will be readily obtained as the same becomes better understood by reference to the following detailed description when considered in conjunction with the accompanying drawings in which: Fig. 1 is a schematic block diagram of a bicycle braking system according to a first embodiment; Fig. 2 a partial schematic block diagram of a Fig. 1 shown bicycle braking system; Fig. 3 a cross-sectional view of a braking device of the Fig. 1 shown bicycle braking system; Fig. 4 a perspective view of the braking device of the Fig. 1 shown bicycle braking system; Fig. 5 a side view of the braking device of the Fig. 1 shown bicycle braking system; Fig. 6 a partial perspective view of the braking device of the Fig. 1 shown bicycle braking system; Fig. 7 is a schematic diagram of the bicycle braking system, with a graph indicating first information and second information; Fig. 8 is a schematic diagram of the bicycle braking system, with a graph indicating first information and second information; Fig. 9 is a graph indicating first information and second information for explaining a method of detecting a comparison value; Fig. 10 a flow chart of an operation of the Fig. 1 shown bicycle braking system; Fig. 11 a flow chart of an operation of the Fig. 1 shown bicycle braking system; Fig. 12 a flow chart of an operation of the Fig. 1 shown bicycle braking system; Fig. 13 is a schematic block diagram of a bicycle braking system according to a second embodiment; and Fig. 14 a side view of the Fig. 13 shown bicycle brake system. DESCRIPTION OF THE EMBODIMENTS

[0022] The embodiments will now be described with reference to the accompanying drawings, wherein like reference numerals designate corresponding or identical elements throughout the various drawings. First embodiment

[0023] If one initially refers to Fig. 1, a bicycle brake system 10 according to a first embodiment comprises an operating device 12 and a braking device 14.

[0024] The operating device 12 includes an operating element 16 configured to be operated by a user. In the illustrated embodiment, the operating device 12 is, for example, a hydraulic operating device and is configured to be mounted on a handlebar (not shown).

[0025] The braking device 14 is configured to apply a braking force to a movable element M1 of a bicycle in response to an operation of the operating element 16. In the illustrated embodiment, the movable element M1 is a wheel having a rim. Possible examples of the movable element M1 include a wheel and a disc brake rotor rotatable together with a wheel. The braking device 14 is configured to be mounted, for example, on a bicycle frame (not shown).

[0026] As in Fig. 1, the braking device 14 comprises at least one friction element configured to come into contact with the movable element M1. In the embodiment shown, the braking device 14 comprises, as the at least one friction element, a first friction element 18 and a second friction element 20 configured to sandwich the movable element M1 between the first friction element 18 and the second friction element 20 to apply the braking force to the movable element M1. While the braking device 14 comprises the first friction element 18 and the second friction element 20, the braking device 14 may comprise at least one friction element, such as the first friction element 18 or the second friction element 20.

[0027] The first friction element 18 and the second friction element 20 are worn due to sliding relative to the movable element M1. The wear of each of the first friction element 18 and the second friction element 20 increases a clearance C1 between the movable element M1 and each of the first friction element 18 and the second friction element 20. This reduces the response of the bicycle brake system 10.

[0028] In order to maintain a quick response of the braking device 14, as shown in Fig. 1, the bicycle brake system 10 includes a sensor device 22 (may also be referred to as a sensing device) and an adjusting device 24. The sensor device 22 is configured to measure first information and second information. The first information relates to an operating amount of the operating element 16. The second information relates to an operating force of the operating element 16. The sensor device 22 is electrically connected to the adjusting device 24. The sensor device 22 is configured to output the first information and the second information to the adjusting device 24.

[0029] As in Fig. 1, the adjustment device 24 is configured to adjust a position of the at least one friction element based on the first information and the second information. The adjustment device 24 is configured to adjust the clearance C1 between the movable element M1 and each of the first friction element 18 and the second friction element 20 based on the first information and the second information. The adjustment device 24 includes an actuating device 26 and an adjustment control device 28.

[0030] The actuating device 26 is configured to actuate the braking device 14 to move the at least one friction element 18 and / or 20. For example, the actuating device 26 comprises a motor, such as a stepper motor, a servo motor, or a DC motor. In the illustrated embodiment, the actuating device 26 is described as the stepper motor. The actuating device 26 may comprise an actuating device other than a motor, if needed and / or desired.

[0031] The adjustment control device 28 is configured to control the actuating device 26 to move the at least one friction element 18 and / or 20 based on the first information and the second information. In the embodiment shown, the adjustment control device 28 is configured to control the actuating device 26 to move the first friction element 18 and the second friction element 20 based on the first information and the second information. More specifically, the adjustment control device 28 is configured to control the actuating device 26 to adjust the clearance C1 between the movable element M1 and each of the first friction element 18 and the second friction element 20 based on the first information and the second information.The adjustment control device 28 is configured to generate drive signals to control an amount of output rotation of the actuating device 26 and a direction of rotation of the actuating device 26.

[0032] The adjustment control device 28 is configured as a processor. The adjustment control device 28 includes a central processing unit (CPU) 28a, a read-only memory (ROM) 28b, and a random access memory (RAM) 28c. For example, a program stored in the ROM 28b is read into the CPU 28a, thereby performing various functions of the adjustment control device 28.

[0033] As in Fig. 1, the bicycle braking system 10 further includes a hydraulic hose 30 configured to hydraulically couple the operating device 12 to the braking device 14. The sensor device 22 is connected to the hydraulic hose 30 to measure the second information. The sensor device 22 may be connected to the operating device 12 or the braking device 14 to measure the second information, if needed and / or desired.

[0034] The bicycle brake system 10 further includes a battery 32 configured to supply power to the sensor device 22 and the adjustment device 24. The sensor device 22, the adjustment control device 28 of the adjustment device 24, and the battery 32 are mounted, for example, on the bicycle frame (not shown).

[0035] As in Fig. As can be seen in Figure 2, the operating device 12 comprises a main body 34 configured to pivotally support the operating element 16. The operating element 16 is pivotable relative to the main body 34 between a rest position P11 and an operated position P12.

[0036] In the present application, the term "rest position" as used herein refers to a position in which a movable part, such as an operating element 16, remains stationary in a state in which the movable part is not operated by the user. The term "operated position" as used herein refers to a position in which the movable part has been operated by the user to perform an operation of a bicycle component, such as the braking device 14.

[0037] The operating device 12 includes a master cylinder 36 and a master piston 38. The master cylinder 36 is provided on the main body 34. The master piston 38 is movably provided within the master cylinder 36 to define a main chamber 40 configured to generate hydraulic pressure in response to an operation of the operating member 16 as the operating force. The operating member 16 is operatively connected to the master piston 38. The hydraulic pressure generated by the master piston 38 is transmitted from the operating device 12 to the braking device 14 via the hydraulic hose 30.

[0038] The operating device 12 includes a main biasing element 42 and a reservoir container 44. The main biasing element 42 is provided in the main chamber 40 to bias the main piston 38. The main biasing element 42 is configured to bias the operating element 16 toward the rest position P11 via the main piston 38.

[0039] The reservoir container 44 is configured to be in fluid communication with the main chamber 40. The reservoir container 44 includes a fluid reservoir 44a and a flexible diaphragm 44b. The flexible diaphragm 44b is disposed within the fluid reservoir 44a to define a fluid chamber 44c configured to be in fluid communication with the main chamber 40. The flexible diaphragm 44b is configured to change an internal volume of the fluid chamber 44c in response to the hydraulic pressure of the main chamber 40.

[0040] As in Fig. 2, the sensor device 22 includes a first sensor 46 configured to measure, as the first piece of information, an operating angle of the operating element 16 relative to the main body 34. For example, the first sensor 46 is configured to measure an absolute angular position of the operating element 16 relative to the main body 34. Accordingly, it can be said that the first sensor 46 is configured to detect angular positions of the operating element 16 in order to measure the operating angle of the operating element 16 relative to the main body 34. Possible examples of the first sensor 46 include a rotary encoder. The first sensor 46 can be mounted on the operating device 12.

[0041] The sensor device 22 includes a second sensor 48 configured to measure, as the second piece of information, an operating force exerted by the operating element 16 on the brake device 14. For example, the second sensor 48 is configured to measure the hydraulic pressure of the main chamber 40 as the second piece of information. More specifically, the second sensor 48 is configured to measure the hydraulic pressure in the hydraulic hose 30. The second sensor 48 is configured to be connected to the hydraulic hose 30. Examples of the second sensor 48 include an oil pressure sensor.

[0042] The braking device 14 includes a secondary cylinder 50 and a secondary piston 52 movably provided in the secondary cylinder 50. More specifically, the secondary piston 52 is movably provided in the secondary cylinder 50 to define a secondary chamber 54 configured to be connected to the main chamber 40 via the hydraulic hose 30. The secondary piston 52 has a central axis A1 and is movable relative to the secondary cylinder 50 in an axial direction D1 parallel to the central axis A1. The secondary piston 52 is movable relative to the secondary cylinder 50 in the axial direction D1 between a rest position P21 and an actuated position P22.

[0043] As in Fig. 2, the rest position P21 of the secondary piston 52 corresponds to the rest position P11 of the operating element 16. The actuated position P22 of the secondary piston 52 corresponds to the operated position P12 of the operating element 16. When the operating element 16 is operated by a user from the rest position P11 to the operated position P12, the hydraulic pressure in the main chamber 40, the hydraulic hose 30 and the secondary cylinder 50 increases. This causes hydraulic fluid to flow from the main chamber 40 to the secondary chamber 54 via the hydraulic hose 30, moving the secondary piston 52 in the secondary cylinder 50 from the rest position P21 to the actuated position P22 in a first axial direction D11.When the operating element 16 is returned to the rest position P11 by the biasing force of the main biasing element 42, the secondary piston 52 is moved relative to the secondary cylinder 50 in a second axial direction D12, which is opposite to the first axial direction D11, to the rest position P21.

[0044] As in Fig. As shown in Figure 3, the secondary cylinder 50 includes a cylinder bore 50a, an inlet port 50b, and a vent port 50c. The secondary piston 52 is movably provided within the cylinder bore 50a to define the secondary chamber 54. The inlet port 50b and the vent port 50c communicate with the secondary chamber 54. The inlet port 50b is configured to be connected to the hydraulic hose 30 via a ring fitting and a ring fitting bolt (not shown). A vent nipple or vent plug (not shown) is attached to the vent port 50c.

[0045] As in Fig. 3, the braking device 14 comprises a transmission element 55 configured to transmit the operating force from the operating element 16 to the at least one friction element 18 and / or 20. The at least one friction element 18 and / or 20 is movable from a rest position P31 toward the movable element M1 in response to the operating force transmitted by the transmission element 55. The actuating device 26 is configured to move the transmission element 55 to change the rest position P31 of the at least one friction element 18 and / or 20.

[0046] In the illustrated embodiment, the first friction element 18 and the second friction element 20 are each movable from the rest position P31 toward the movable element M1 in response to the operating force transmitted by the transmission element 55. The actuating device 26 is configured to move the transmission element 55 to change the rest position P31 of each of the first friction element 18 and the second friction element 20.

[0047] The rest position P31 of each of the first friction element 18 and the second friction element 20 is defined by a portion that does not come into contact with the movable element M1 in each of the first friction element 18 and the second friction element 20. This is because the rest position P31 is not affected by wear of each of the first friction element 18 and the second friction element 20.

[0048] As in Fig. 3, the transmission element 55 is coupled to the secondary piston 52 to move together with the secondary piston 52 relative to the secondary cylinder 50. The braking device 14 includes a piston support member 56 and a return biasing member 57. The piston support member 56 is fixed to the secondary cylinder 50 to movably support the secondary piston 52 in the axial direction D1.

[0049] The return biasing element 57 is configured to bias the secondary piston 52 toward the rest position P21. Namely, the transmission element 55 is biased by the return biasing element 57 toward a rest position P41, which corresponds to the rest position P21 of the secondary piston 52. When the secondary piston 52 moves relative to the secondary cylinder 50 in the first axial direction D11 toward the actuated position P22, the transmission element 55 moves relative to the secondary cylinder 50 in the first axial direction D11 toward an actuated position P42.

[0050] As in Fig. 4, the braking device 14 further includes a base frame 58, a first arm 60, a second arm 62, a first pivot shaft 64, and a second pivot shaft 66. The base frame 58 is configured to be mounted to the bicycle frame (not shown). The first arm 60 is pivotally attached to the base frame 58 via the first pivot shaft 64. The second arm 62 is pivotally attached to the base frame 58 via the second pivot shaft 66. The first arm 60 is pivotable relative to the base frame 58 about a first pivot axis A11. The second arm 62 is pivotable relative to the base frame 58 about a second pivot axis A12, which is substantially parallel to the first pivot axis A11.

[0051] As in Fig. 5, the first arm 60 includes a first coupling end 68 and a first attachment end 70 opposite the first coupling end 68 relative to the first pivot axis A11. In the embodiment shown, the secondary cylinder 50 is pivotally coupled to the first coupling end 68 to transmit the operating force to the first arm 60. The first friction element 18 is attached to the first attachment end 70. As shown in the Fig. 5 and Fig. 6, the secondary cylinder 50 includes first coupling portions 71 configured to engage the first coupling end 68 of the first arm 60.

[0052] As in Fig. 5, the second arm 62 includes a second coupling end 72 and a second attachment end 74 opposite the second coupling end 72 relative to the second pivot axis A12. The transmission element 55 is pivotally coupled to the second coupling end 72 of the second arm 62 to transmit the operating force to the second arm 62. The second friction element 20 is attached to the second attachment end 74. As shown in the Fig. 5 and Fig. 6, the transmission element 55 comprises second coupling portions 75 which are designed to engage with the second coupling end 72 of the second arm 62.

[0053] As in Fig. 5, the braking device 14 further includes an arm biasing member 76 configured to bias the first arm 60 and the second arm 62 such that the first friction element 18 and the second friction element 20 are positioned at the rest positions P31. The arm biasing member 76 includes a first end portion 78 and a second end portion 80. The first end portion 78 is configured to engage the first arm 60. The second end portion 80 is configured to engage the second arm 62. The arm biasing member 76 is configured to bias the first arm 60 and the second arm 62 such that the first coupling end 68 and the second coupling end 72 approach each other.

[0054] The rest positions P31 of the first friction element 18 and the second friction element 20 are defined by a relative position between the secondary cylinder 50 and the transmission element 55 in the axial direction D1 in a rest state of the braking device 14. When the transmission element 55 moves away from the secondary cylinder 50 in the first axial direction D11, the first friction element 18 and the second friction element 20 approach each other. This reduces the clearances C1 between the movable element M1 and each of the first friction element 18 and the second friction element 20.

[0055] As in Fig. As can be seen in Figure 3, the transmission element 55 is attached to the actuating device 26 and, together with the actuating device 26, is movable relative to the secondary cylinder 50. The transmission element 55 includes a through-opening 55a. The secondary piston 52 is inserted into the through-opening 55a of the transmission element 55.

[0056] While in the embodiment shown, the actuating device 26 is provided on the braking device 14, the actuating device 26 may be provided on the operating device 12 if needed and / or desired. In such an embodiment, the actuating device 26 is configured to change a relative position between the operating element 16 and the main piston 38 such that the braking device 14 is actuated to move the at least one friction element 18 and / or 20 via the hydraulic fluid. In this case, for example, the reservoir container 44 is omitted from the operating device 12 in order to reliably transmit the movement of the actuating device 26 to the braking device 14 via the hydraulic fluid.

[0057] As in Fig. 3, the adjustment device 24 includes an adjustment gear 82 configured to move the transmission element 55 relative to the secondary piston 52 in response to actuation of the actuating device 26. The adjustment gear 82 includes a first gear 84 and a second gear 86. The first gear 84 is configured to mesh with an output gear 88 of the actuating device 26. The second gear 86 is configured to mesh with the first gear 84. The first gear 84 and the second gear 86 are rotatably attached to the transmission element 55.

[0058] The second gear 86 is fixed to the secondary piston 52. More specifically, the second gear 86 includes a threaded hole 86a. The secondary piston 52 includes a threaded portion 52a configured to engage with the threaded hole 86a. The actuator 26 rotates the second gear 86 relative to the secondary piston 52 to move the transmission member 55 relative to the secondary piston 52 in the axial direction D1. Namely, the actuator 26 rotates the second gear 86 relative to the secondary piston 52 and the transmission member 55 to change the clearances C1 in a rest state in which the first friction element 18 and the second friction element 20 are disposed at the rest positions P31.

[0059] As in Fig. 7, the hydraulic pressure P of the main chamber 40 changes in response to the operating angle θ of the operating element 16. The hydraulic pressure P measured by the second sensor 48 is due to the flexible membrane 44b of the reservoir container 44 ( Fig. 2) is essentially zero while the operating element 16 is pivoted from the rest position P11 to an angular position Ps1. However, the hydraulic pressure P measured by the second sensor 48 increases to a first hydraulic pressure P1 after the internal volume of the fluid chamber 44c reaches a maximum volume.

[0060] The first hydraulic pressure P1 depends essentially on a preload force of the return preload element 57 ( Fig. 2). The hydraulic pressure is transmitted from the main chamber 40 to the secondary chamber 54 of the brake device 14 via the hydraulic fluid in the hydraulic hose 30. The hydraulic pressure transmitted to the secondary chamber 54 moves the secondary piston 52 and the transmission element 55 relative to the secondary cylinder 50 against the biasing force of the return biasing element 57 in the first axial direction D11.

[0061] The relative movement between the transmission element 55 and the secondary cylinder 50 pivots the first arm 60 and the second arm 62 about the first pivot axis A11 and the second pivot axis A12. The hydraulic pressure of the main chamber 40 is maintained at the first hydraulic pressure P1 until the first friction element 18 and the second friction element 20 come into contact with the movable contact element M1. The first friction element 18 and the second friction element 20 come into contact with the movable element M1 when the operating element 16 reaches an angular position Ps2. Thus, the hydraulic pressure P1 is maintained between the angular positions Ps1 and Ps2 of the operating element 16. An operating angle θ1 defined between the angular positions Ps1 and Ps2 depends on the clearances C1.

[0062] As in Fig. As seen in Fig. 7, when the operating member 16 is further pivoted from the angular position Ps2, the first friction member 18 and the second friction member 20 are pressed against the movable member M1 by the hydraulic pressure from the operating device 12. At this time, the hydraulic pressure P further increases from the first hydraulic pressure P1 in response to elastic deformation of each of the first friction member 18 and the second friction member 20, causing the braking force to be applied from the first friction member 18 and the second friction member 20 to the movable member M1.

[0063] As in Fig. As shown in Figure 8, each of the clearances C1 increases depending on the amount of wear of each of the first friction element 18 and the second friction element 20. An increase in each of the clearances C1 increases the operating angle θ1 of the operating element 16. Specifically, when the clearances C1 increase, the first friction element 18 and the second friction element 20 come into contact with the movable member M1 when the operating element 16 reaches an angular position Ps3 beyond the angular position Ps2. Thus, the hydraulic pressure P1 is maintained between the angular positions Ps1 and Ps3 of the operating element 16. An operating angle θ2 defined between the angular positions Ps1 and Ps3 is larger than the operating angle θ1 defined between the angular positions Ps1 and Ps2. This reduces the response of the bicycle brake system 10.

[0064] In order to maintain the quick response in the bicycle brake system 10, the adjustment control device 28 ( Fig. 1) is designed to detect, based on the first information and the second information, a comparison value relating to the clearance C1 between the at least one friction element 18 and / or 20 and the movable element M1. In more detail, the adjustment control device 28 is designed such that the CPU 28a ( Fig. 1) calculates the comparison value based on the first information and the second information and the CPU 28a stores the comparison value in the RAM 28c ( Fig. 1). In the embodiment shown, possible examples of the comparison value include a size of the clearance and a value indicating the size of the clearance. For example, the comparison value may include the operating angle of the operating element 16, which corresponds to the clearance C1. The adjustment control device 28 serves as a clearance value detection part, which is configured to detect, based on the first information and the second information, the comparison value relating to the clearance C1 between the at least one friction element 18 and / or 20 and the movable element M1.

[0065] The adjustment control device 28 is designed to detect, as a comparison value, the operating angle of the operating element 16 corresponding to the clearances C1 based on the angular position of the operating element 16 and the hydraulic pressure of the main chamber 40.

[0066] As in Fig. 9, the adjustment control device 28 is configured to compare the hydraulic pressure P measured by the second sensor 48 with a first reference pressure Pr1. The first reference pressure Pr1 is stored in the ROM 28b ( Fig. 1). The adjustment control device 28 is configured to detect, as a first angular position, an angular position Ps11 measured by the first sensor 46 when the hydraulic pressure P measured by the second sensor 48 is higher than the first reference pressure Pr1. The first angular position Ps11 is stored in the RAM 28c.

[0067] The adjustment control device 28 is configured to compare the hydraulic pressure P measured by the second sensor 48 with a second reference pressure Pr2 that is higher than the first reference pressure Pr1. The second reference pressure Pr2 is stored in the ROM 28b. The adjustment control device 28 is configured to detect, as a second angular position, an angular position Ps12 measured by the first sensor 46 when the hydraulic pressure P measured by the second sensor 48 is higher than the second reference pressure Pr2. The adjustment control device 28 is configured to store the second angular position Ps12 detected by the adjustment control device 28.

[0068] The adjustment control device 28 is configured to calculate an operating angle between the first angular position Ps11 and the second angular position Ps12. More specifically, the adjustment control device 28 is configured to subtract the first angular position Ps11 from the second angular position Ps12 to calculate an operating angle θ11. The operating angle θ11 is stored in the RAM 28c as the comparison value.

[0069] As in Fig. As can be seen in Figure 9, the first angular position Ps11 is smaller than, but substantially equal to, the angular position Ps1. The second angular position Ps12 is greater than, but substantially equal to, the angular position Ps2. The operating angle θ11 is substantially equal to the operating angle θ1. Indeed, it can be said that the operating angle θ11 essentially corresponds to the clearance C1.

[0070] As in Fig. 1, the adjustment control device 28 is configured to compare the comparison value with a reference value in an adjustment mode. In the adjustment mode, the adjustment control device 28 is configured to adjust the clearance C1 between the at least one friction element 18 and / or 20 and the movable element M1 based on the first information and the second information. In the embodiment shown, the adjustment control device 28 is configured to compare the operating angle θ11 with a reference operating angle θr1. The reference operating angle θr1 is stored in the RAM 28c as the reference value. The adjustment control device 28 serves as a clearance value comparator configured to compare the comparison value with the reference value.

[0071] The adjustment control device 28 is configured to control the actuating device 26 to move the at least one friction element 18 and / or 20 based on a comparison between the comparison value and the reference value. The adjustment control device 28 serves as an actuating device driver configured to control the actuating device 26 to move the at least one friction element 18 and / or 20 based on a comparison between the comparison value and the reference value.

[0072] The comparison value (the operating angle θ11) detected by the adjustment control device 28 may vary slightly even if the amount of wear of each of the first friction element 18 and the second friction element 20 does not change. Accordingly, in the illustrated embodiment, an average of comparison values (the operating angles) detected by the adjustment control device 28 is used as the comparison value (as the operating angle) in the adjustment mode.

[0073] More specifically, the adjustment control device 28 is configured to store the first to N1-th latest comparison values. N1 is an integer greater than or equal to 2. In the shown embodiment, for example, the adjustment control device 28 is configured to store the first to tenth latest operation angles θc1 to θc10 as the first to N1-th latest comparison values. The first latest operation angle θc1 is the newest data among the first to tenth operation angles θc1 to θc10. The first latest operation angle θc10 is the oldest data among the first to tenth operation angles θc1 to θc10. The adjustment control device 28 serves as a latest space memory configured to store the first to N1-th latest comparison values.

[0074] When the adjustment control device 28 detects a new comparison value (a new operation angle), the first to N1-th latest comparison values are updated. More specifically, the new comparison value (the new operation angle) is stored in the RAM 28c as the first latest comparison value (as the first latest operation angle θc1). The previous first to ninth latest comparison values (the previous first to ninth latest operation angles θc1 to θc9) are stored in the RAM 28c as the second to tenth latest comparison values (as the second to tenth latest operation angles θc2 to θc10), respectively. The previous tenth latest comparison value (the previous tenth latest operation angle θc10) is deleted from the RAM 28c.

[0075] As in Fig. 1, the adjustment control device 28 is configured to calculate an average value of the first to N1-th most recent comparison values as a comparison value. In the embodiment shown, the adjustment control device 28 is configured to calculate the average value of the first to tenth most recent reference operating angles θc1 to θc10 as an average operating angle θav1. The adjustment control device 28 is configured to store the average operating angle θav1. The adjustment control device 28 is configured to compare the average operating angle θav1 with the reference operating angle θr1. The adjustment control device 28 is configured to control the actuating device 26 to move the at least one friction element 18 and / or 20 based on a comparison between the average operating angle θav1 and the reference operating angle θr1.

[0076] The total number of the first to tenth latest comparison values (the first to tenth latest operation angles θc1 to θc10) stored in the adjustment control device 28 is not limited to ten. The adjustment control device 28 may store at least first and second latest comparison values (first and second latest operation angles θc1 and θc2) among the comparison values (operation angles) acquired by the adjustment control device 28.

[0077] Furthermore, the adjustment control device 28 may store only the first most recent comparison value (the first most recent operating angle θc1) acquired by the adjustment control device 28, if needed and / or desired. In such an embodiment, the adjustment control device 28 does not need to calculate the average value of the first to N1-th most recent comparison values, and the first most recent operating angle θc1 is used as the comparison value instead of the average value of the first to N1-th most recent comparison values to adjust the clearance C1.

[0078] As in Fig. As shown in Figure 1, the adjustment control device 28 is configured to control the actuating device 26 to adjust the clearance C1 between the at least one friction element 18 and / or 20 and the movable element M1 in a case where the comparison value is larger than the reference value by a reference difference value or more. In the illustrated embodiment, the adjustment control device 28 is configured to control the actuating device 26 to adjust the clearance C1 in a case where the average operating angle θav1 is larger than the reference operating angle θr1 by the reference difference value Dr1 or more. For example, the reference difference value Dr1 is stored in the ROM 28b.

[0079] The bicycle brake system 10 has a setting mode in addition to the adjustment mode. The adjustment control device 28 is configured to allow a user to select one of the adjustment mode and the setting mode via a mode selector (not shown). The adjustment control device 28 is configured to determine a mode of the bicycle brake system 10 based on mode information input by a user via the mode selector.

[0080] As in Fig. 1, the adjustment control device 28 is configured to acquire the reference value based on the first information and the second information in the adjustment mode. In the illustrated embodiment, the adjustment control device 28 is configured to acquire the reference operating angle θr1 in the adjustment mode based on the operating angle of the operating member 16 and the hydraulic pressure of the main chamber 40. The adjustment control device 28 serves as a reference acquisition part configured to acquire the reference value based on the first information and the second information in the adjustment mode.

[0081] The adjustment control device 28 is configured to store the first to N2-th most recent comparison values in the adjustment mode. N2 is an integer greater than or equal to 2. In the illustrated embodiment, the adjustment control device 28 is configured to store the first to fifth most recent operating angles θs1 to θs5 in the RAM 28c in the adjustment mode. In the RAM 28c, the first to N2-th most recent comparison values are stored in a storage area different from a storage area for the first to N1-th comparison values. The adjustment control device 28 serves as a reference free space memory configured to store the first to N2-th most recent comparison values in the adjustment mode.

[0082] As in Fig. 1, the adjustment control device 28 is configured to calculate, as a reference value, an average value of the first to N2-th most recent comparison values in the setting mode. In the illustrated embodiment, the adjustment control device 28 is configured to calculate, as the reference operating angle θr1, an average value of the first to fifth most recent operating angles θs1 to θs5 stored in the RAM 28c. However, the adjustment control device 28 may be configured to store a comparison value as a reference value in the setting mode without calculating the average value of the first to N2-th most recent comparison values.

[0083] After the first friction element 18 and the second friction element 20 are replaced with new friction elements, or after the clearance C1 between the movable member M1 and each of the first friction element 18 and the second friction element 20 is readjusted, the reference value (the reference operating angle θr1) is adjusted by the adjustment control device 28 based on the operating angle of the operating element 16 and the hydraulic pressure of the main chamber 40 in the adjustment mode. This allows the adjustment control device 28 to readjust the reference value (the reference operating angle θr1) according to the new friction element and / or the newly adjusted size of the clearance C1.

[0084] The method of adjusting the clearance C1 between the movable member M1 and each of the first friction member 18 and the second friction member 20 will be described in detail with reference to FIG. Fig. 10 to 12 explained.

[0085] As in Fig. As can be seen in Figure 10, in a case where the adjustment mode is selected, the comparison value calculation begins in steps S1 and S2. More specifically, based on the first information and the second information, the adjustment control device 28 acquires the comparison value relating to the clearance C1 between the at least one friction element 18 and / or 20 and the movable element M1 ( Fig. 1). In the illustrated embodiment, the latest comparison value (the latest operating angle θc1) is detected by the adjustment control device 28 based on the operating angle and the hydraulic pressure.

[0086] In step S3, the average value of the comparison values is calculated by the adjustment control device 28. In the illustrated embodiment, the average operating angle θav1 is calculated by the adjustment control device 28 based on the first to tenth most recent reference operating angles θc1 to θc10.

[0087] In step S4, the adjustment control device 28 compares the comparison value with the reference value. More specifically, the adjustment control device 28 determines whether the average operating angle θav1 is larger than the reference operating angle θr1 by the reference difference value Dr1 or more. In a case where it is determined that the average operating angle θav1 is not larger than the reference operating angle θr1 by the reference difference value Dr1 or more, steps S1 to S4 are repeated every time the braking device 14 is operated.

[0088] In step S5, in a case where it is determined that the average operating angle θav1 is larger than the reference operating angle θr1 by the reference difference value Dr1 or more, the operating device 26 is controlled by the adjustment control device 28 to adjust the clearance C1 between the movable member M1 and each of the first friction element 18 and the second friction element 20. More specifically, as shown in Fig. 3, a drive signal from the adjustment control device 28 ( Fig. 1) is sent to the actuator 26, so that the actuator 26 moves the transmission member 55 relative to the secondary piston 52 by a predetermined amount of axial movement. This moves the first friction member 18 and the second friction member 20 toward the movable member M1 by a predetermined distance corresponding to the predetermined amount of axial movement. Accordingly, it is possible to adjust the size of the clearance C1 to be closer to or equal to a size of clearance corresponding to the reference value.

[0089] While the axial movement of the transmission element 55 is constant in an adjustment operation, in the shown embodiment, the axial movement of the transmission element 55 can be changed according to the difference between the average operation angle θav1 and the reference operation angle θr1.

[0090] As in Fig. 10, in step S6, the latest comparison values are deleted from the adjustment control device 28. The above steps S2 to S6 are repeated in the adjustment mode, so that the clearance C1 is adjusted substantially to a clearance corresponding to the reference value.

[0091] Fig. 11 shows the process of step S2 ( Fig. 10) to detect the comparison value. More specifically, in step S21, the second information (the hydraulic pressure of the main chamber 40) is measured by the second sensor 48. When the operating element 16 is operated by the user, the hydraulic pressure P of the main chamber 40 varies as shown in Fig. 9 shown.

[0092] As in Fig. 11, in step S22, the hydraulic pressure P measured by the second sensor 48 is compared with the first reference pressure Pr1 by the adjustment control device 28. In a case where the hydraulic pressure P measured by the second sensor 48 is equal to or lower than the first reference pressure Pr1, steps S21 and S22 are repeated. In step S23, the angular position measured by the first sensor 46 is detected as the first angular position Ps11 by the adjustment control device 28 when the hydraulic pressure P measured by the second sensor 48 is higher than the first reference pressure Pr1 ( Fig. 9). The first angular position Ps11 is stored in the RAM 28c of the adjustment control device 28 ( Fig. 1) stored.

[0093] In step S24, the second information (the hydraulic pressure of the main chamber 40) is measured by the second sensor 48. In a case where the hydraulic pressure P measured by the second sensor 48 is equal to or lower than the second reference pressure Pr2, steps S24 and S25 are repeated. In step S25, the hydraulic pressure P measured by the second sensor 48 is compared with the second reference pressure Pr2 by the adjustment control device 28. In step S26, the angular position measured by the first sensor 46 is detected as the second angular position Ps12 by the adjustment control device 28 when the hydraulic pressure P measured by the second sensor 48 is higher than the second reference pressure Pr2 ( Fig. 9). The second angular position Ps12 is stored in the RAM 28c of the adjustment control device 28 ( Fig. 1) stored.

[0094] In step S27, the comparison value is calculated by the adjustment control device 28 based on the first angular position Ps11 and the second angular position Ps12. More specifically, the operating angle θ11 ( Fig. 9) is calculated by the CPU 28a based on the first angular position Ps11 and the second angular position Ps12 stored in the RAM 28c ( Fig. 1).

[0095] In step S28, the latest comparison values are updated in the adjustment control device 28. More specifically, the operation angle θ11 calculated by the CPU 28a in step S27 is stored as the first latest operation angle θc1 in the RAM 28c. The previous first to ninth latest operation angles θc1 to θc9 are respectively stored as the second to tenth latest operation angles θc2 to θc10. The previous tenth latest operation angle θc10 is deleted from the RAM 28c. In step S3 of Fig. 10, the average value of the updated first to tenth latest reference operating angles θc1 to θc10 is calculated by the adjustment control device 28.

[0096] As in Fig. 12, in the setting mode, the average value of the first to N2-th most recent comparison values is calculated by the adjustment control device 28 as a reference value. More specifically, in step S41, a repetition count M of detecting a comparison value in the setting mode is reset to zero. In steps S42 to S48, an operating angle is detected by the adjustment control device 28, as well as in steps S21 to S27 of Fig. 11. Since steps S42 to S48 are essentially the same as steps S21 to S27 as described in Fig. 11, these are not described in detail here for the sake of brevity.

[0097] In step S49, the repetition count M is incremented by one. In step S50, the repetition count M is compared with a reference repetition count Mr. If the repetition count M is not equal to the reference repetition count Mr, steps S42 to S50 are repeated. In the illustrated embodiment, the reference repetition counter M1 is set to five, corresponding to the first to fifth most recent operating angles θs1 to θs5.

[0098] In a case where the repetition count M is equal to the reference repetition count Mr, the average value of the first to N2-th latest comparison values stored in the RAM 28c is calculated as the comparison value by the adjustment control device 28. More specifically, the average value of the first to fifth latest operation angles θs1 to θs5 stored in the RAM 28c is calculated by the CPU 28a as the reference operation angle θr1. The average value of the first to fifth latest operation angles θs1 to θs5 is stored in the RAM 28c as the reference operation angle θr1.

[0099] In step S52, steps S41 to S51 are repeated in a case where the setting mode is selected in the mode selector (not shown). The process is returned to step S2 in a case of Fig. 10 by selecting the adjustment mode on the mode selector (not shown). In the adjustment mode, the average value of the first to fifth most recent operating angles θs1 to θs5 acquired in the setting mode is used as the reference value (the reference operating angle θr1).

[0100] In the bicycle brake system 10, the sensor device 22 is configured to measure the first information regarding the operation amount of the operating element 16 and the second information regarding the operating force of the operating element 16. Accordingly, it is possible to detect the clearance C1 between the at least one friction element 18 and / or 20 and the movable element M1 based on the first information and the second information. Furthermore, the adjusting device 24 is configured to adjust the position of the at least one friction element 18 and / or 20 based on the first information and the second information.Accordingly, it is possible to adjust the clearance C1 between the at least one friction element 18 and / or 20 and the movable element M1 according to the first information and the second information, which enables the bicycle brake system 10 to maintain the quick response regardless of the wear of the at least one friction element 18 and / or 20. Second embodiment

[0101] A bicycle brake system 210 according to a second embodiment is described below with reference to the Fig. 13 and Fig. 14. Elements having essentially the same function as those in the first embodiment are numbered alike here and, for the sake of brevity, are not described and / or illustrated in detail again.

[0102] Unlike the bicycle brake system 10, the bicycle brake system 210 uses a mechanical operating system instead of the hydraulic operating system. More specifically, as shown in Fig. 13, the bicycle brake system 210 includes a control cable 231 in place of the hydraulic hose 30. The control cable 231 is operatively coupled to the operating member 16 and the braking device 14 to transmit the movement of the operating member 16 to the braking device 14. Possible examples of the control cable 231 include a Bowden cable.

[0103] As in Fig. As shown in Figure 14, the control cable 231 includes an outer sheath 231a and an inner wire 231b. The outer sheath 231 movably supports the inner wire 231b. The inner wire 231b extends through an interior of the outer sheath 231a. One end of the inner wire 231b is configured to operatively couple the operating member 16 to the second coupling end 72 of the second arm 62.

[0104] As in Fig. As shown in Figure 14, one end of the outer sheath 231a is connected to the first coupling end 68 of the first arm 60. The control cable 231 includes an adjusting element 231c, such as an adjusting nut. The adjusting element 231c is configured to couple the end of the outer sheath 231a to the first coupling end 68 of the first arm 60. The adjusting element 231c is configured to adjust a relative position between the outer sheath 231a and the first coupling end 68 of the first arm 60 in a direction D4 defined along the inner wire 231b. For example, rotation of the adjustment element 231c relative to the first arm 60 changes the relative position between the outer casing 231a and the first coupling end 68 of the first arm 60. This changes the clearance C1 in a rest state in which the operating element 16 is not operated by the user.

[0105] In this embodiment, as shown in Fig. 13, the sensor device 22 comprises a second sensor 248 configured to measure the second information relating to the operating force of the operating element 16. In the embodiment shown, the second sensor 248 is configured to measure the operating force transmitted from the operating element 16 to the second arm 62 via the inner wire 231b ( Fig. 14) of the control cable 231. Examples of the second sensor 248 include a strain sensor having a strain gauge. The strain gauge (not shown) of the second sensor 248 is attached, for example, to the inner wire 231b or a coupling portion between one end of the inner wire 231b and the operating member 16.

[0106] As in the Fig. 13 and Fig. 14, the adjusting device 24 comprises an actuating device 226 which is designed to actuate the braking device 14 in order to move the at least one friction element 18 and / or 20. In the embodiment shown, as in Fig. 14, the actuating device 226 is configured to rotate the adjusting element 231c relative to the first coupling end 68 of the first arm 60. The actuating device 226 is mounted on the first coupling end 68 of the first arm 60. The secondary cylinder 50, the secondary piston 52, and the transmission element 55 are omitted from the braking device 14.

[0107] With the bicycle brake system 210, it is possible to achieve the same advantageous effect as with the bicycle brake system 10 according to the first embodiment.

[0108] To adjust the clearance C1, in the second embodiment, the actuator 226 is configured to adjust the relative position between the outer sheath 231a and the first coupling end 68 of the first arm 60 via the adjusting element 231c. However, the actuator 226 may be configured to adjust a relative position between one end of the inner wire 231b and the second coupling end 72 of the second arm 62, if needed and / or desired. Furthermore, the actuator 226 may be mounted on the operating device 12, if needed and / or desired.

[0109] The term "configured," as used herein to describe a component, section, or part of a device, includes hardware and / or software designed and / or programmed to perform the desired function. The desired function may be performed by hardware, software, or a combination of hardware and software.

Claims

[1] Bicycle brake system (10; 210), comprising: an operating device (12) comprising an operating element (16) adapted to be operated by a user; a braking device (14) configured to exert a braking force on a movable element (M1) of a bicycle in response to an operation of the operating element (16), wherein the braking device (14) comprises at least one friction element (18, 20) configured to come into contact with the movable element (M1); a sensor device (22) which is designed first information regarding an operation amount of the operating element (16) and to measure second information relating to an operating force of the operating element (16); and an adjusting device (24) configured to adjust a position of the at least one friction element (18, 20) based on the first information and the second information, wherein the adjusting device (24) is designed to adjust a clearance (C1) between the movable element (M1) and the at least one friction element (18, 20) based on the first information and the second information. [2] Bicycle brake system (10; 210) according to claim 1, wherein the adjusting device (24) comprises an actuating device (26; 226) configured to actuate the braking device (14) to move the at least one friction element (18, 20), and an adjustment control device (28) configured to control the actuating device (26; 226) to move the at least one friction element (18, 20) based on the first information and the second information. [3] Bicycle brake system (10; 210) according to claim 2, wherein the braking device (14) comprises a transmission element (55) which is designed to transmit the operating force from the operating element (16) to the at least one friction element (18, 20), the at least one friction element (18, 20) is movable from a rest position (P11, P21, P31) towards the movable element (M1) in response to the operating force transmitted by the transmission element (55), and the actuating device (26; 226) is designed to move the transmission element (55) in order to change the rest position (P11, P21, P31) of the at least one friction element (18, 20). [4] Bicycle brake system (10; 210) according to claim 3, wherein the braking device (14) comprises a secondary cylinder (50), and a secondary piston (52) movably provided in the secondary cylinder (50), and the transmission element (55) is coupled to the secondary piston (52) in order to move together with the secondary piston (52) relative to the secondary cylinder (50). [5] Bicycle brake system (10; 210) according to one of claims 2 to 4, wherein the adjustment control device (28) is designed to detect a comparison value based on the first information and the second information, which comparison value relates to a clearance (C1) between the at least one friction element (18, 20) and the movable element (M1). [6] Bicycle brake system (10; 210) according to claim 5, wherein the adjustment control device (28) is designed to compare the comparison value with a reference value, and the adjustment control device (28) is designed to control the actuating device (26) to move the at least one friction element (18, 20) based on a comparison between the comparison value and the reference value. [7] Bicycle brake system (10; 210) according to claim 6, wherein the adjustment control device (28) is designed to store the first to N1-th most recent comparison values, where N1 is an integer greater than or equal to 2, the adjustment control device (28) is designed to calculate an average value of the first to N1-th most recent comparison value as the comparison value, and the adjustment control device (28) is designed to control the actuating device (26) to adjust the clearance (C1) between the at least one friction element (18, 20) and the movable element (M1) in a case where the comparison value is greater than the reference value by a reference difference value or more. [8] Bicycle brake system (10; 210) according to one of claims 6 or 7, wherein the adjustment control device (28) is configured to detect the reference value based on the first information and the second information in an adjustment mode. [9] Bicycle brake system (10; 210) according to one of claims 6 to 8, wherein the adjustment control device (28) is adapted to store the first to N2-th latest comparison values in the setting mode, where N2 is an integer greater than or equal to 2, and the adjustment control device (28) is adapted to calculate an average value of the first to N2-th latest comparison values in the setting mode as a reference value. [10] Bicycle brake system (10; 210) according to one of claims 1 to 9, wherein the operating device (12) comprises a main body (34) which is designed to pivotally support the operating element (16), and the sensor device (22) comprises a first sensor (46) which is designed to measure, as the first information, an operating angle of the operating element relative to the main body. [11] Bicycle brake system (10; 210) according to one of claims 1 to 10, wherein the sensor device (22) comprises a second sensor (48) which is designed to measure, as the second information, an operating force exerted by the operating element (16) on the brake device (14). [12] Bicycle brake system (10; 210) according to claim 10 or 11, further comprising: a hydraulic hose (30) which is designed to hydraulically couple the operating device (12) to the braking device (14), wherein the operating device (12) comprises a master cylinder (36), and a main piston (38) movably provided in the master cylinder (36) to define a main chamber (40) configured to generate hydraulic pressure in response to an operation of the operating member (16) as the operating force, and the braking device (14) comprises a secondary cylinder (50), and a secondary piston (52) movably provided in the secondary cylinder (50) to define a secondary chamber (54) adapted to be connected to the main chamber (40) via the hydraulic hose (30). [13] Bicycle brake system (10; 210) according to claim 12, wherein the second sensor (48) is configured to measure the hydraulic pressure as the second information. [14] Bicycle brake system (10; 210) according to one of claims 1 to 13, wherein the braking device (14) comprises, as the at least one friction element (18, 20), a first friction element (18) and a second friction element (20) which are configured to sandwich the movable element (M1) between the first friction element (18) and the second friction element (20) to exert the braking force on the movable element (M1).

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