Anti-rollover system for a bicycle

Abstract

To prevent a bicycle from flipping over due to excessive braking force applied to the front brake caliper of a hydraulic braking system, an anti-flip-over system incorporates a single solenoid valve. The system measures the instantaneous deceleration of the bicycle and its instantaneous tilt angle relative to a horizontal reference. The solenoid valve closes automatically, interrupting the fluidic connection between the master cylinder and the caliper. This prevents the brake fluid pressure acting on the caliper from increasing further as the bicycle's deceleration approaches a threshold that, considering the incline of the surface on which the bicycle is traveling, would result in a flip-over.

Description

Technical field

[0001] The present invention relates to a system to prevent a bicycle from tipping over on its front wheel when the front brake is applied excessively. background

[0002] There are several patent publications relating to anti-lock braking systems (“ABS”) for motorcycles, bicycles and e-bikes, and products are marketed for all these vehicle types.

[0003] Existing technologies for bicycles and e-bikes include systems that have been simplified to eliminate the need for a hydraulic pump; see, for example, DE 10158382 A1 and WO 2014 / 108235 A1. These patent publications both propose ABS systems that rely on wheel speed sensors to detect vehicle movement. WO 2014 / 108235 A1 also discloses the use of a pressure sensor to detect the pressure within the hydraulic brake circuit. The aforementioned patent publications also disclose a hydraulic brake control circuit that employs two solenoid-controlled valves and a hydraulic accumulator. These devices are all commonly used in anti-lock braking systems for cars and motorcycles.

[0004] WO 2021 / 260149 A1 discloses an anti-lock braking system that relies on only one solenoid-controlled valve and uses speed sensors and a pressure sensor.

[0005] Passive hydraulic pressure limiting devices are also sold to restrict the power of bicycle brakes, for example, the passive pressure limiting valve marketed as "OutBreaker," which requires manual adjustment of the pressure limit. The pressure limit can only be set by the rider through trial and error. The rider might adjust the device on a flat road, only to find that the bicycle easily flips over on a downhill slope, or that the brakes lose significant power during a long descent, making it impossible for the rider to stop the bicycle.

[0006] DE 10 2012 222058 A1 discloses a device for controlling a bicycle's braking system. The device has a control for releasing the hydraulic pressure in the brake circuit when the rear wheel lifts off the ground. Problem to be solved

[0007] The problem to be solved is that of a bicycle "rolling over" when the front brake is applied excessively. The braking friction force applied to the bicycle at the contact point between the front wheel and the road surface causes a moment to be exerted on the bicycle and rider, who together have a relatively high center of mass. As a result of this moment, weight is transferred from the rear wheel to the front wheel until, at a certain deceleration, the rear wheel lifts off the road. This situation can be avoided by a skilled rider who is able to modulate the braking force to prevent the rear wheel from lifting. However, an inexperienced rider may lack sufficient judgment to assess the maximum safe deceleration of the bicycle, especially in an emergency.Once the rear wheel has lifted off the road, the bicycle becomes extremely unstable, and it is likely that the rider will fall and suffer an injury.

[0008] Attempts have been made to use a conventional anti-lock braking system (ABS) to prevent rear wheel lift and the resulting bicycle rollover. The ABS system can monitor the bicycle's deceleration and block the flow of hydraulic fluid to the front brake caliper to limit deceleration before rear wheel lift occurs. Deceleration is typically monitored by one of two known methods.

[0009] The first known method involves estimating the bicycle's deceleration using one or more speed sensors that detect the bicycle's speed by monitoring the movement of gears attached to the bicycle's wheels. This method has significant drawbacks: speed sensors are expensive, especially when the cost of the gears, mounting brackets, and wiring systems is added. Another disadvantage is that the bicycle's deceleration is difficult to calculate accurately and continuously when the speed can only be updated each time a gear passes the speed sensor. This is a particular problem for bicycles, where the wheel's rolling radius is conventionally much larger than that of the gear, and riding speeds are quite low.Consequently, the time intervals between the teeth passing the speed sensors are quite long.

[0010] The second known method for estimating a bicycle's deceleration involves measuring the hydraulic pressure in the brake caliper. This method also has drawbacks. The first is the cost of the pressure sensor itself. The second disadvantage is that the estimation method relies on knowing the coefficient of friction between the brake pad and the brake disc. This is an unstable parameter that varies depending on temperature, wear, and environmental conditions. The pressure threshold at which the ABS system blocks the fluid flow to the brake caliper must therefore be set to a conservative value to reliably prevent wheel spin, potentially resulting in unnecessarily long stopping distances, which in turn creates a further safety risk.This could be a particular problem during a long downhill run, where the increased temperature of the brake components could cause a very low coefficient of friction between the brake pad and disc, resulting in greatly reduced braking performance. Overview of the invention

[0011] It is an object of the present invention to provide an anti-rollover system (ARS) that is potentially less expensive and less complex than an ABS system, while offering greater safety than a passive pressure relief valve.

[0012] A specific objective of the invention is to prevent the occurrence of a rollover before it begins.

[0013] The invention utilizes a single solenoid valve to allow or block a fluid connection between the master cylinder and the brake caliper. According to one aspect of the present invention, an electronic anti-rollover system acts as a brake force limiter with a solenoid valve that automatically closes, interrupting the fluid connection between the brake master cylinder and the brake caliper and therefore preventing the pressure of the brake fluid acting on the brake caliper from increasing further as the deceleration of the bicycle approaches a threshold which, taking into account the inclination of the surface on which the bicycle is traveling, would determine a state in which the bicycle would tip over.

[0014] According to one aspect of the present invention, an anti-rollover system as defined in claim 1 is provided. According to another aspect, the present invention provides an anti-rollover method according to claim 13. Preferred embodiments are defined in the dependent claims. Character description Fig. Figure 1 is a schematic view of a bicycle equipped with an anti-rollover system; Fig. Figure 2 is a schematic cross-sectional view of an anti-rollover unit according to an embodiment of the present invention; Fig. 3A and Fig. 3B are views of the unit of Fig. 2 in two different operating states; Fig. 4 and Fig. 5 are diagrams showing the relationship between the slope of the road surface and the forces acting on the bicycle and its rider; Fig. Figure 6 is a schematic view of the unit of Fig. 2 in a normal braking condition; and Fig. Figure 7 is a schematic view of the unit of Fig. 2 in an activated state. Detailed description

[0015] The installation of an anti-rollover system (ARS) on a bicycle is shown schematically in Fig. Figure 1 shows a bicycle 10, in this example an e-bike, equipped with a hydraulic braking system. The bicycle 10 has a frame 18 and a front wheel 11, which is fitted with a brake disc 12 and an associated brake caliper 13 that applies a braking torque to the brake disc. A manual control lever 14 (or hand lever) operates a hydraulic master cylinder 15 to generate and control pressure within a hydraulic brake circuit 16.

[0016] Reference numeral 20 designates an anti-rollover system (ARS) unit, which detects the risk of the bicycle tipping over and limits the bicycle's deceleration accordingly. A battery 21 supplies the ARS unit with energy via wiring 22. When the ARS unit is fitted into an e-bike, it can be powered by the same battery as the traction motor.

[0017] The ARS unit 20 has a housing 23 ( Fig. 2) which contains a solenoid valve 24 and electronic and mechanical components. The housing 23 provides environmental protection for the internal components and can also provide mounting brackets (not shown) that can be used to securely attach the ARS unit 20 to the bicycle frame 18.

[0018] The present anti-rollover system utilizes a single electrically actuated valve, the solenoid valve 24. The solenoid valve 24 comprises a valve body 25, which forms an inner cavity 26 that defines a longitudinal or axial direction. A valve piston 27 is housed to slide axially within the inner cavity 26.

[0019] Within the valve body 25, an upstream port 28 (or inlet port or master cylinder port), a downstream port 29 (or outlet port or caliper port), and a number of channels fluidically connecting the upstream port 28, the downstream port 29, and the inner cavity 26 are formed. In operation, the upstream port 28 is fluidically connected to the master cylinder 15, while the downstream port 29 is fluidically connected to at least one caliper 13. Terms such as "upstream" and "downstream" are to be interpreted as referring to a pressure flow originating from the master cylinder and directed through the ARS unit to the caliper.

[0020] The valve piston 27 is suitably shaped and hydraulically connected to the upstream and downstream ports so that the movement of the valve piston 27 within the inner cavity 26 connects the channels within the valve body 25 to provide the hydraulic function of the ARS unit.

[0021] As explained in detail below and as described in the Fig. 3A and Fig. As shown schematically in Figure 3B, the valve piston 27 has two alternative positions: a normal brake position ( Fig. 3A), in which the hydraulic channels connect the master cylinder 15 to the brake caliper 13, and an activated ARS position, or closed position ( Fig. 3B), in which the channels connecting the master cylinder to the brake caliper are closed by the valve piston.

[0022] The inner cavity 26 has an upstream end 30 which is fluidically connected to the upstream port 28, and an axially opposite downstream end 31 which is fluidically connected to the downstream port 29.

[0023] In the compact embodiment shown in the figures, the upstream and downstream connections 28, 29 are preferably located adjacent to each other, relatively close to each other on the same side of the valve body 25.

[0024] An outlet channel 32 runs axially through one side of the valve body 25 and opens at the lower or downstream end 31 of the inner cavity 26.

[0025] According to a preferred embodiment, the inner cavity 26 forms a transversely narrower upstream section 26a and a transversely wider downstream section 26b. The valve piston 27 can accordingly form a transversely narrower upstream cylindrical section 27a, which is housed in the transversely narrower upstream section 26a of the inner cavity 26, and a transversely wider downstream section 27b, which is housed in the transversely wider downstream section 26b of the inner cavity 26.

[0026] Three longitudinally adjacent annular seals 35-37 are mounted axially spaced apart from each other on the upstream region 27a of the valve piston 27: an upstream seal 35, a downstream seal 37 and an intermediate seal 36. All three seals are in sliding contact with the upstream section 26a of the inner cavity 26.

[0027] To reduce the axial travel required for the piston to open and close the fluid connection between the master cylinder and the brake caliper, the intermediate seal 36 preferably provides a conical lip that tapers towards the upstream port 28, whereby, when the pressure of the brake fluid in the downstream part or brake caliper part of the circuit is greater than the pressure in the upstream part or master cylinder part of the circuit, the conical lip acts as a one-way valve.

[0028] An axial channel 38 extends from an upstream end 39 of the valve piston 27 to a transverse channel 33, which is formed transversely by the valve piston and has side openings 51 located axially between the intermediate and downstream seals.

[0029] A bypass channel 42 opens at the transversely narrower upstream section 26a of the inner cavity 26 and thereby connects the outlet channel 32, and therefore the outlet or downstream connection 29, fluidically with the inner cavity 26.

[0030] A return spring 40 pushes the valve piston 27 towards the upstream port 28. In the exemplary embodiment of Fig. 2 surrounds the return spring 40 part of the wider, downstream area 27b of the valve piston and is axially compressed between a radially inwardly projecting rib 41 formed by the valve body 25 and a transverse step 43 formed by the valve piston 27.

[0031] An electromagnetic coil 44 is provided around a region of the inner cavity 26, in this example around a downstream part of the downstream section 26b, in order to surround a length of the downstream region 27b of the valve piston 27.

[0032] At least a part of the valve body 25, in particular a region 25b of the valve body 25 surrounding the electromagnetic coil 44, is made of a material with high magnetic permeability and low magnetic hysteresis, such as soft iron. Similarly, at least a part of the valve piston 27, in particular the region 27b of the valve piston surrounded by the electromagnetic coil 44, is made of a material with high magnetic permeability and low magnetic hysteresis, such as soft iron. When energized, the electromagnetic coil 44 causes a magnetic flux MF ( Fig. 3B) flows through a magnetic circuit that includes the magnetically permeable parts 25b, 27b of the valve body 25 and the valve piston 27. This magnetic flux generates an axial force that opposes the axial force of the return spring 40.

[0033] Embodiments may provide that parts of the valve body 25 and parts of the valve piston 27, which are not surrounded by the electromagnetic coil 44, may be made of a material other than soft iron, preferably aluminum or aluminum alloys, or austenitic stainless steel. According to these variant embodiments, the valve body and the valve piston may each consist of two firmly secured parts made of different materials.

[0034] As in the illustrative example of Fig. As shown in Figure 2, the valve piston 27 has the downstream section 27b, which is made, for example, of soft iron, firmly secured to and integral with the upstream section 27a, which is made, for example, of an aluminum alloy.

[0035] In the example of Fig. 2 The valve body 25 has the downstream area 25b, which is made, for example, of soft iron, firmly secured to and integral with the upstream area 25a, which is made, for example, of austenitic stainless steel.

[0036] A printed circuit board 45 within the housing 23 provides a mounting for a number of electrical / electronic components and electrical connections between them. The electrical components may include a power supply connector 46, input / output devices, electrical switching devices (not shown), a processing unit 47, an external electronic interface 49 (for example, a Bluetooth interface), and an inertial measurement unit (IMU) 48.

[0037] The IMU 48 is an electronic device that detects and reports data on the acceleration and orientation of the bicycle using a combination of accelerometers and gyroscopes.

[0038] In particular, the IMU 48 can include one or more accelerometers that provide real-time data regarding the longitudinal acceleration and deceleration of the bicycle. In this context, the term "accelerometer" is to be interpreted broadly to include any device or apparatus for measuring a variation in speed in the longitudinal direction, that is, the forward direction of movement of the bicycle.

[0039] The IMU 48 also provides real-time data regarding the current angular orientation of the bicycle in relation to a given direction, for example in relation to a horizontal line or a horizontal plane, by means of at least one gyroscope.

[0040] The processing unit 47, preferably a microprocessor, is configured to execute a real-time control application loaded into its memory. This application controls the current within the electromagnetic coil 44 in response to data collected by the inertial measurement unit 48. This enables the solenoid valve 24 to control the connections between the hydraulic channels to prevent the bicycle from tipping over.

[0041] The energy connector 46 connects the processing unit 47, the IMU 48 and the electromagnetic coil 44 to the energy source 21.

[0042] Preferably, the processing unit 47 can also communicate with a user application using the external interface 49, through which the rider can input certain configuration data (for example, his size and weight, and the wheelbase, mass and rolling radius of the bicycle) into a memory associated with the processing unit 47.

[0043] The processing unit 47 continuously calculates an "activation threshold," which is a value of the bicycle's deceleration that is lower than a "decelMax" value by a defined safety margin. The "decelMax" value is the deceleration at which the bicycle's rear wheel lifts off the road surface. This value varies and depends on constant and variable parameters. The constant parameters include the mass of the rider and bicycle, and the position of the center of mass relative to the bicycle's geometric characteristics. The variable parameters include the instantaneous angle of inclination of the road surface and the instantaneous deceleration of the bicycle. The constant parameters are inputted by the rider, while the variable parameters are detected by the IMU 48.

[0044] Using the data entered through the external interface 49, the processing unit 47 determines ( Fig. 4) the position of the center of mass: h = height of the center of mass (of the bicycle and the rider) above the road surface, xf = longitudinal distance between the center of the front wheel and the center of mass; rr = wheel rolling radius; θ = Inclination angle of the road surface (reference point is determined by the gyroscope) made available in the IMU 48); xs=h×sin θ x1=xF×cos θ−xs+rr×sinθ

[0045] The currently variable value of decelMax is continuously calculated as follows. With reference to Fig. 5: FMax×h=M⋅g⋅x1 where M is the total mass of the bicycle and the rider; however, the parameter M does not need to be entered.

[0046] The moment at which the bicycle begins to roll is when the gravitational moment around the point of contact between the front wheel and the road is equal to the deceleration moment around the same point. FMax=(M⋅g⋅x1) / hMaximum deceleration force

[0047] Solving for Fmax gives the maximum deceleration force. decelMax=FMax / M=(Mgx1) / (hM) decelMax=(g⋅x1) / h maximum deceleration (m / s2)

[0048] As is obvious, the parameter M cancels out in the above equation and does not need to be taken into account when assessing the height of the center of mass.

[0049] The "decelmax" value represents the maximum deceleration force that can be applied to the bicycle without causing it to tip over. The ARS unit controls the brakes by applying a maximum braking force that results in a deceleration less than the decelMax value.

[0050] The ARS system operates as follows. Based on data from the inertial measurement unit 48, the real-time control application constantly monitors the bicycle's angular orientation relative to a horizontal reference plane, and thus the road's inclination. Using the inclination reference point and data about the rider and bicycle geometry, the processing unit 47 continuously calculates the deceleration limit value, decelMax. The processing unit 47 also continuously calculates an "activation threshold," which is a bicycle deceleration value lower than decelMax by a defined safety margin.

[0051] During normal braking ( Fig. 6) The control system continuously monitors the longitudinal deceleration of the bicycle based on data from the inertial measurement unit 48, and, if there is no risk of a rollover, the longitudinal deceleration is less than the activation threshold. During braking, the pressurized brake fluid enters the solenoid valve 24 through the master cylinder port 28 and flows through the channels 33, 38 in the valve piston 27 and the channels 42, 32 in the valve body 25 into all channels and volumes within the solenoid valve. The pressure of the brake fluid on the left side of the valve piston is equal to the pressure acting on the right side of the valve piston.Therefore, the hydraulic thrust acting on the left side of the valve piston is equal to the hydraulic thrust acting on the right side of the valve piston, thus no resultant axial force is applied to the valve piston by the brake fluid, and the valve piston is held in its rest position (towards the right side) by the return spring 40. Fig. 3A and Fig. 6) held.

[0052] During heavy braking ( Fig. 7) The longitudinal delay level received by the inertial measurement unit 48 reaches the activation threshold. The control algorithm commands that the electromagnetic coil 44 be energized, which generates a magnetic flux in the solenoid body and the valve piston components, and the resulting force pulls the valve piston 27 against its return spring 40 into the position of Fig. 3B and Fig. 7. The upstream and intermediate seals 35, 36 block the fluid connection between the inner cavity 26 and the downstream port 29, thus interrupting the flow of brake fluid from the upstream port to the downstream port and therefore between the master cylinder and the brake caliper.

[0053] Assuming the rider panics and pulls as hard as possible on the manual control lever, so that the bicycle is on the verge of flipping over, the electromagnetic coil is energized and moves the valve piston to the left, preventing more pressure from being forced into the brake caliper. In fact, when the valve piston 27 is in the activated position of the Fig. 3B and Fig. 7, and if the rider continues to apply force to the brake lever, the pressure at the upstream port continues to rise. However, since the path between the master cylinder port and the caliper port of the ARS valve is blocked by seals 35 and 36, the master cylinder side of the valve is not fluidically connected to the caliper side of the valve, and therefore the pressure in the caliper remains constant and cannot rise further.

[0054] The brake fluid with caliper pressure exerts a force on the valve piston in a right-hand direction, whereas the fluid with master cylinder pressure exerts a force in a left-hand direction.

[0055] As long as the total or resultant hydraulic force applied to the valve piston holds the solenoid valve in the position of Fig. 3B and Fig. Holding position 7 prevents the brake fluid pressure acting on the brake caliper from increasing further.

[0056] Preferably, the upstream 35 and the downstream 36 seals have the same diameter. Therefore, as long as the master cylinder pressure remains higher than the brake caliper pressure, the total hydraulic force applied to the valve piston holds the solenoid valve in the position specified in the Fig. 3B and Fig. 7 shown position and prevents the brake fluid acting on the brake caliper from rising further.

[0057] Consequently, the electromagnetic coil 44 does not need to remain energized, and the processing unit 47 can implement a control algorithm that switches off the current in the electromagnetic coil after a very short period of time, and the solenoid valve is held in the position of Fig. 3B and Fig. 7 remain as long as sufficient master cylinder pressure is present. Even when the electromagnetic coil 44 is switched off, because the pressure acting on the piston from the master cylinder side is higher than the pressure acting on the caliper side of the valve piston, there will be a resulting leftward force that holds the piston in the left position without the coil needing to remain switched on. In other words, the valve remains activated even when the electromagnetic coil is disconnected from the power supply. As a result, embodiments may provide that, in order to save electrical energy, the processing unit 47 can be configured to automatically switch off the electromagnetic coil after it has been activated.Advantageously, there is no need to monitor and control the point at which the deceleration falls below the threshold to unlock the solenoid valve again, as the solenoid valve unlocks naturally as soon as the rider releases the brake lever.

[0058] In the state in which the braking deceleration reaches the threshold value and the solenoid valve is actuated, the valve piston may be in contact with the lower or downstream end 31 of the inner cavity 26.

[0059] The level of bicycle deceleration remains close to the activation threshold, which, because it has a safety margin below the value of decelMax, ensures that the rear wheel of the bicycle remains in contact with the road and the bicycle does not overturn, while the bicycle keeps both wheels on the ground and the brakes decelerate the bicycle as much as possible. According to a preferred embodiment, the processing unit 47 can be calibrated to supply energy to the electromagnetic coil when a value of approximately 90 percent of the deceleration “decelMax” at which the bicycle would overturn is detected.

[0060] When the rider reduces the force applied to the hand lever, the pressure in the master cylinder section of the circuit decreases. As long as the bicycle's deceleration remains below the activation threshold, the current in the electromagnetic coil remains off. Once the pressure in the master cylinder circuit is sufficiently low, the total hydraulic force acting on the valve piston can no longer counteract the force of the return spring.

[0061] Preferably the three seals 35, 36, 37 have the same diameter, so that when the pressure of the brake fluid on the upstream side drops during braking, the valve piston 27 will slide back into its original, normal braking position ( Fig. 3A and Fig. 6), which connects the master cylinder port and the brake caliper port and equalizes their pressure. Fluid can now flow from the brake caliper back to the master cylinder, and the system returns to its normal braking mode ( Fig. 6).

[0062] It is understood that with the present anti-rollover system, the risk of a rollover is detected solely using an inertial measurement unit (i.e., an accelerometer and a gyroscope). The anti-rollover system does not require measurement of wheel speed or hydraulic pressure. QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] DE 10158382 A1

[0003] WO 2014 / 108235 A1

[0003] WO 2021 / 260149 A1

[0004] DE 10 2012 222058 A1

[0006]

Claims

[1] Anti-rollover system for preventing a bicycle from tipping over due to excessive braking force applied to a front wheel brake caliper of a hydraulic braking system, the anti-rollover system comprising: a solenoid valve (24) with a valve body (25) forming an upstream port (28) that can be fluidically connected to a master cylinder, a downstream port (29) that can be fluidically connected to a front wheel brake caliper (13), an inner cavity (26) that is fluidically connected to the upstream and downstream ports (28, 29), and a valve piston (27) that is movable within the inner cavity (26); an electromagnetic coil (44) which is mounted in the valve body (25) and surrounds at least part of the inner cavity (26) and at least part of the valve piston (27); an inertial measurement unit (48), comprising a deceleration measuring device for measuring the instantaneous deceleration of the bicycle and an inclination angle measuring device for measuring the instantaneous orientation of the bicycle in relation to a horizontal reference; a processing unit (47) that is configured to Receiving real-time data on the deceleration and orientation of the bicycle from the inertial measurement unit (48), continuous processing, during braking, of the deceleration and alignment data and calculation of an instantaneous maximum deceleration value at which, depending on the detected instantaneous value of the tilt angle, a rear wheel of the bicycle lifts off the road surface, continuous comparison of the calculated instantaneous maximum deceleration value with the instantaneous measured deceleration value, and automatic supply of energy to the electromagnetic coil (44) upon detection that the measured instantaneous delay value reaches or exceeds an activation threshold value that is lower than the calculated instantaneous maximum delay value by a preset safety margin, causing the energized electromagnetic coil (44) to move the valve piston (27) from a released position in which the valve piston (27) allows a fluid connection between the upstream (28) and downstream (29) ports through the inner cavity (26), in a closed position in which the valve piston (27) interrupts the fluidic connection between the upstream (28) and downstream (29) ports, thus preventing the master brake cylinder from further increasing the pressure of the brake fluid acting on the front brake caliper (13). [2] Anti-rollover system according to claim 1, wherein the solenoid valve (24) comprises a return spring (40) which pushes the valve piston (27) in the direction of the released position. [3] Anti-rollover system according to claim 1 or 2, wherein at least one area (27b) of the valve piston (27) is surrounded by the electromagnetic coil (44) and is made of a material with high magnetic permeability and low magnetic hysteresis, at least one area (25b) of the valve body (25) is made of a material with high magnetic permeability and low magnetic hysteresis and surrounds the electromagnetic coil (44). [4] Anti-rollover system according to claim 3, wherein the areas (27b, 25b) of the valve piston (27) and the valve body (25) are made of soft iron. [5] Anti-rollover system according to any one of the preceding claims, wherein an outlet channel (32) formed in the valve body (25) fluidically connects the downstream port (29) with a downstream end (31) of the inner cavity (26); an upstream end (30) of the inner cavity (26), which is axially opposite the downstream end (31), is fluidically connected to the upstream connection (28); a bypass channel (42) is formed in the valve body (25) to connect the inner cavity (26) fluidically to the downstream port (29), and has an opening (50) on the inner cavity (26); Three longitudinally adjacent annular seals (35, 36, 37) are mounted axially spaced apart from each other on the valve piston (27) in sliding contact with the inner cavity (26): an upstream seal (35), a downstream seal (37) and an intermediate seal (36); one or more channels (38, 33) through the valve piston (27) from an upstream end (39) of the valve piston to at least one side opening (51) of the valve piston, which is arranged axially between the intermediate seal (36) and the downstream seal (37); In the released position of the valve piston (27), the opening (50) of the bypass channel (42) is located between the downstream seal (37) and the intermediate seal (36), whereby the opening (50) of the bypass channel (42) is in fluid communication with the at least one side opening (51) in the valve piston (27) and a fluid connection is established between the upstream (28) and the downstream (29) port; and In the closed position of the valve piston (27) the opening (50) of the bypass channel (42) is located between the intermediate seal (36) and the upstream seal (35), whereby the opening (50) of the bypass channel (42) is not in fluid communication with the at least one side opening (51) in the valve piston (27) and the fluid connection between the upstream (28) and the downstream (29) port is interrupted. [6] Anti-rollover system according to one of the preceding claims, wherein the seals (35, 36, 37) have the same diameter. [7] Anti-rollover system according to one of the preceding claims, wherein the intermediate seal (36) provides a conical lip which tapers towards the upstream connection (28). [8] Anti-rollover system according to one of the preceding claims, wherein the outlet channel (32) extends axially through one side of the valve body (25). [9] Anti-rollover system according to any one of the preceding claims, further comprising: a memory from which the processing unit (27) receives configuration data about the size of the rider and the bicycle; and an external interface (49) through which the configuration data can be entered by the driver. [10] Anti-rollover system according to one of the preceding claims, wherein the deceleration measuring device comprises at least one accelerometer and the inclination angle measuring device comprises at least one gyroscope. [11] Anti-rollover system according to one of the preceding claims, wherein the system is free of speed sensors for detecting the speed of the bicycle. [12] Anti-rollover system according to one of the preceding claims, wherein the system is free of pressure sensors for measuring hydraulic pressure acting on the brake caliper. [13] Anti-rollover method for preventing a bicycle from tipping over due to excessive braking force applied to a front wheel brake caliper of a hydraulic braking system, the method comprising: Providing an anti-rollover system according to any one of the preceding claims, During braking, continuous measurement of the instantaneous deceleration of the bicycle and the instantaneous orientation of the bicycle in relation to a horizontal reference, During braking, a continuous calculation of an instantaneous maximum deceleration value is performed, at which, depending on the detected instantaneous value of the tilt angle, a rear wheel of the bicycle lifts off the road surface, and continuous comparison of the calculated instantaneous maximum deceleration value with the instantaneous measured deceleration value, and automatic supply of energy to the electromagnetic coil (44) of the solenoid valve upon detection that the measured instantaneous deceleration value reaches or exceeds an activation threshold value which is lower by a preset safety margin than the calculated instantaneous maximum deceleration value, thereby interrupting the fluidic connection between upstream (28) and downstream (29) terminals and consequently preventing the pressure of the brake fluid acting on the front brake caliper (13) from increasing further. [14] Anti-rollover method according to claim 13, wherein the step of continuously measuring the instantaneous deceleration of the bicycle and the continuous measuring of the instantaneous value of the inclination angle is preceded by the following step: Input, into a memory associated with the processing unit (47), configuration data about the rider size, wheelbase and rolling radius of the bicycle, and wherein The step of continuously calculating an instantaneous maximum deceleration value (decelMax) at which a rear wheel of the bicycle lifts off the road surface is also performed as a function of the following parameters: Height (h) of the common center of mass of the rider and the bicycle above the road surface, Longitudinal distance (xf) between the center of the front wheel and the center of mass, Wheel rolling radius (rr), and Inclination angle (θ) of the road surface. [15] Anti-rollover method according to claim 13 or 14, wherein the step of supplying energy to the electromagnetic coil (44) is carried out upon detection that the measured instantaneous deceleration value reaches or exceeds approximately 90 percent of the calculated instantaneous maximum deceleration value (decelMax). [16] Braking system for a bicycle, comprising: an anti-rollover system according to any one of claims 1 to 12; a front wheel brake caliper (13) for applying a braking torque to the front wheel (11) of a bicycle; a power supply unit (21) for supplying electrical energy to the electromagnetic coil (44), the inertial measurement unit (48) and the processing unit (47) of the anti-rollover system; a manual control lever (14) and an associated hydraulic master cylinder (15); a hydraulic brake circuit (16) which fluidly connects the solenoid valve (24) of the anti-rollover system to the master cylinder (15) and the front wheel brake caliper (13).

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