MOTORCYCLES" DESCRIPTION

FIELD OF APPLICATION

[0001] The present invention further relates to a braking system of the brake-by-wire (BBW) type , in particular for motorcycles .

BACKGROUND ART

[0002] In motorcycles , there are brake-by-wire type braking systems in which the user can manually operate two separate manual controls , typically a lever on the handlebar, and a pedal , so as to send a request for braking action to an appropriate control unit .

[0003] Such a request for braking action is switched to actuation of one or more electric motors acting on the friction elements ( typically pads , but also shoes ) of the braking devices with which the motorcycle is provided . Under normal operating conditions , the user thus does not directly command the actuation of the braking devices but sends a braking request which is met by said electric motors , by means of a control unit .

[0004] In case of a mal function, the system must allow a hydraulic back-up to ensure that the user can at least partially brake the motorcycle by means of direct action on the manual operating devices . [0005] The motorcycle solutions of the prior art do not allow operating the hydraulic back-up by means of both controls ( lever and brake pedal ) in case of failure of the E/E system (ECU, actuators , sensors , etc . ) or in case of lack of power supply ( disconnected battery) combined with the need to have a partially fluid- free brake system actuation ( at least one fully electromechanical caliper or axle - DRY) . Finally, the need is felt to provide braking systems being compatible with electric vehicles (blending with regenerative braking, residual torque reduction) .

PRESENTATION OF THE INVENTION

[0006] The need is thus felt in the art to provide a braking system which allows solving the technical problems mentioned with reference to the prior art .

[0007] The need is met by a braking system according to claim 1 .

[0008] In particular, such a need is met by a braking system for a motorcycle comprising a first braking device operatively connectable to a first wheel of the motorcycle , and provided with a first hydraulic supply circuit , first manually operated hydraulic device provided with a first manually operated control and a first hydraulic delivery circuit fluidly connectable to the first hydraulic supply circuit , a second braking device operatively connectable to said first wheel or to a second wheel of the motorcycle , and provided with a second hydraulic supply circuit , distinct from or coinciding with the first hydraulic supply circuit , a second manually operated hydraulic device provided with a second manually operated control and a second hydraulic delivery circuit fluidly connectable to the second hydraulic supply circuit , an electric actuator having electric or electromechanical motor means operatively connected to an electrically or electromechanically operated float fluidly connected to a delivery of the electric actuator connected to said first hydraulic supply circuit and/or said second hydraulic supply circuit , where said first and second hydraulic delivery circuits are fluidly connected to each other by the interposition of valve means , where the braking system is provided with a processing and control unit , operatively connected to said electric actuator and said valve means , the processing and control unit being programmed so that : in standard operation, in case of actuation of the first manually operated hydraulic device and/or the second manually operated hydraulic device , it translates the electrically or electromechanically operated float so as to fluidly disconnect the first and/or second hydraulic supply circuit from the first and/or second hydraulic delivery circuit and simultaneously actuate the at least a first braking device and/or the at least a second braking device .

[0009] According to a possible embodiment of the present invention, the processing and control unit is programmed so that : in back-up operation, it backs up or allows the backing up of the electrically or electromechanically operated float so as to allow the fluid connection between the first and/or second hydraulic supply circuit from the first and/or second hydraulic delivery circuit and simultaneously actuate the at least a first braking device and/or the at least a second braking device , when at least one of the first and second manually operated hydraulic devices is operated .

[0010] According to a possible embodiment of the present invention, said valve means comprise a diverter valve having a first inlet port , fluidly connected to the first hydraulic delivery circuit , a second inlet port fluidly connected to the second hydraulic delivery circuit , and a single outlet port in fluid communication with the hydraulic delivery circuit , between said first and second hydraulic delivery circuits , having greater pressure .

[0011] According to a possible embodiment of the present invention, the first hydraulic delivery circuit is provided with at least one control valve , which in standard operation connects the first hydraulic delivery circuit to a first hydraulic braking simulator, and in back-up operation, connects the first hydraulic delivery circuit to the first inlet port of the diverter valve , and/or where the second hydraulic delivery circuit is provided with at least one control valve , which in standard operation connects the second hydraulic delivery circuit to a second hydraulic braking simulator, and in back-up operation, connects the second hydraulic delivery circuit to the second inlet port of the diverter valve .

[0012] According to a possible embodiment of the present invention, the first manually operated device is provided with a first hydraulic fluid tank having a preloaded membrane which ensures an overpressure to compensate for a di f ferent geodetic height with respect to a second hydraulic fluid tank of the second manually operated device .

[0013] According to a possible embodiment of the present invention, said valve means comprise a slide valve controlled by the processing and control unit so that : in the standard condition, the slide valve fluidly separates the first hydraulic delivery circuit , the second hydraulic delivery circuit , and the delivery of the electric actuator from one another, where said delivery supplies said first and second hydraulic supply circuits , in back-up mode , the slide valve puts into communication the first hydraulic delivery circuit with the first hydraulic supply circuit , and the second hydraulic delivery circuit with the second hydraulic supply circuit , and where the slide valve hydraulically separates the first and second hydraulic supply circuits . [0014] According to a possible embodiment of the present invention, the system comprises a main hydraulic fluid tank, which supplies a first tank of the first manually operated hydraulic device and a second tank of the second manually operated hydraulic device , where said main tank is preloaded, and where said preload is such as not to generate a pressure which results in an actuation of the braking devices , where said valve means comprise a slide valve which selectively connects or disconnects the first and second hydraulic delivery circuits to/ from the first and second hydraulic supply circuits , respectively .

[0015] According to a possible embodiment of the present invention, the system comprises a first hydraulic braking simulator connected to the first hydraulic delivery circuit and a second hydraulic braking simulator connected to the second hydraulic delivery circuit , each of said hydraulic braking simulators being provided with a single hydraulic tank, where said valve means 68 comprise a slide valve which selectively connects or disconnects the first and second hydraul ic delivery circuits to/ from the first and second supply circuits , respectively .

[0016] According to a possible embodiment of the present invention, said slide valve is divided into four two-way valves , preferably two normally closed valves and two normally open valves .

[0017] According to a possible embodiment of the present invention, the system comprises a single brake fluid tank, which supplies the first and second hydraulic delivery circuits , upstream of said valve means , said single tank being preloaded under pressure .

[0018] According to a possible embodiment of the present invention, the first and second hydraulic supply circuits are fluidly connected to two braking devices arranged at the front of the vehicle .

[0019] According to a possible embodiment of the present invention, the first and second hydraulic supply circuits are coincident and fluidly connected to a single braking device at the rear of the vehicle .

[0020] According to a possible embodiment of the present invention, said first and second manually operated hydraulic devices are arranged mutually in series and in series with the first and second hydraulic supply circuits , where each manually operated hydraulic device comprises a piston provided with a one-way lip seal at the outlet of the device itsel f .

[0021] According to a possible embodiment of the present invention, the system comprises a brake fluid tank connected directly upstream of the electric actuator by means of a plurality of series of one-way valves which allow the leakage of fluid with the system at atmospheric pressure while preventing the passage in the opposite direction during the actuations of the braking devices in both standard operation and back-up operation .

[0022] According to a possible embodiment of the present invention, said valve means comprise two normally open hydraulic valves which fluidly connect both the manually operated hydraulic devices and two normally closed hydraulic valves to allow the passage of pressure between said manually operated hydraulic devices and the hydraulic supply circuits and prevent the absorption of volume by absorbers connected to the manually operated hydraulic devices in back-up .

[0023] According to a possible embodiment of the present invention, said braking devices comprise disc brakes and/or drum brakes .

[0024] The present invention further relates to a motorcycle comprising a braking system as described above . DESCRIPTION OF THE DRAWINGS

[0025] Further features and advantages of the present invention will become more comprehensible from the following description of preferred embodiments thereof given by way of non-limiting examples , in which :

[0026] f igures 1- 8 are diagrammatic views of a braking system according to di f ferent embodiments of the present invention .

[0027] The elements or parts of elements common to the embodiments described below will be indicated by the same reference numerals .

DETAILED DESCRIPTION

[0028] With reference to the aforesaid figures , reference numeral 4 indicates as a whole a braking system for a vehicle , in particular for a motorcycle 8 .

[0029] The braking system 4 for motorcycle 8 comprises a first braking device 12 operatively connectable to a first wheel (not shown) of the motorcycle 8 , and provided with a first hydraulic supply circuit 16 . Typical ly, the first braking device 12 can comprise a disc brake or a drum brake .

[0030] The braking system 4 comprises at first manually operated hydraulic device 20 provided with a first manually operated control 24 , such as a lever or a pedal , for example , and a first hydraulic delivery circuit 28 fluidly connectable to the first hydraulic supply circuit

16 .

[0031] The braking system 4 further comprises a second braking device 32 operatively connectable to said first wheel or to a second wheel (not shown) of the motorcycle 8 , and provided with a second hydraulic supply circuit 36 distinct from or coinciding with the first hydraulic supply circuit 16 .

[0032] Typically, the second braking device 12 can comprise a disc brake or a drum brake . The second hydraulic supply circuit 36 can be physically distinct from the first hydraulic supply circuit 16 , but it can also converge into the first hydraulic supply circuit 16 so as to coincide therewith .

[0033] The braking system 8 comprises a second manually operated hydraulic device 40 provided with a second manually operated control 44 , typically a lever or a pedal , and a second hydraulic delivery circuit 48 fluidly connectable to the second hydraulic supply circuit 36 .

[0034] The braking system 8 further comprises an electric actuator 52 having electric or electromechanical motor means 56 operatively connected to an electrically or electromechanically operated float 60 fluidly connected to a delivery 64 of the electric actuator 52 fluidly connected to said first hydraulic supply circuit 16 and/or said second hydraulic supply circuit 36 .

[0035] Typically, the delivery 64 is a hydraulic fluid conduit , which fluidly converge into the first hydraulic supply circuit 16 and/or the second hydraulic supply circuit 36 .

[0036] Advantageously, said first and second hydraulic delivery circuits 28 , 48 are fluidly connected to each other by the interposition of valve means 68 , better described below .

[0037] The braking system 8 is provided with a processing and control unit 72 , operatively connected to said electric actuator 52 and said valve means 68 , which is programmed so that , in standard operation, in case of actuation of the first manually operated hydraulic device 20 and/or the second manually operated hydraulic device 40 (with which the user requires a braking action from the system 8 ) , it translates the electrically or electromechanically operated float 60 so as to fluidly disconnect the first and/or second hydraulic supply circuit 16 , 36 from the first and/or second hydraulic delivery circuit 28 , 48 and simultaneously actuate the at least a first braking device 12 and/or the at least a second braking device 32 .

[0038] According to an embodiment , the processing and control unit 72 is programmed so that , in back-up operation, it backs up or allows the backing up of the electrically or electromechanically operated float 60 so as to allow the fluid connection between the first and/or second hydraulic supply circuit 16,36 and the first and/or second hydraulic delivery circuit 28,48 and simultaneously actuate the at least a first braking device 12 and/or the at least a second braking device 32, when at least one of the first and second manually operated hydraulic devices 20,40 is actuated.

[0039] According to a possible embodiment (figures 1-2) , said valve means 68 comprise a diverter valve 76 having a first inlet port 80, fluidly connected to the first hydraulic delivery circuit 28, a second inlet port 82 fluidly connected to the second hydraulic delivery circuit 48, and a single outlet port 84 in fluid communication with the hydraulic delivery circuit, between said first and second hydraulic delivery circuits 28,48, having greater pressure.

[0040] It is thus possible to brake using both manually operated lever or pedal controls and that delivering the most pressure, i.e., that on which the user applies the most pressure (whether the pedal or the lever) prevails, in terms of actuation pressure.

[0041] According to a possible embodiment of the present invention (figures 1-2) , the first hydraulic delivery circuit 28 is provided with at least one control valve 88 , of the NO (normally open) or NC (normally closed) type , which in standard operation connects the first hydraulic delivery circuit 28 to a first hydraulic braking simulator 92 , and in back-up operation, connects the first hydraulic delivery circuit 28 to the first inlet port 80 of the diverter valve 76 , and/or where the second hydraulic delivery circuit 48 is provided with at least one control valve 88 ( of the NO or NC type ) , which in standard operation connects the second hydraulic delivery circuit 48 to a second hydraulic braking simulator 96 , and in back-up operation, connects the second hydraulic delivery circuit 48 to the second inlet port 82 of the diverter valve 76 .

[0042] According to a possible embodiment ( figures 1-2 ) , the first manually operated device 20 is provided with a first hydraulic fluid tank 100 having a preloaded membrane which ensures an overpressure to compensate for a di f ferent geodetic height with respect to a second hydraulic fluid tank 104 of the second manually operated device 40 . The problem of emptying the tank placed at a higher elevation, typically in motorcycles , is thus solved, this being the tank connected to the handlebar lever, elevated above the tank connected to the pedal . [0043] According to a possible embodiment ( figures 3-4 ) , the valve means 68 comprise a slide valve 108 controlled by the processing and control unit 72 so that , in the standard operating condition, the slide valve 108 fluidly separates the first hydraulic delivery circuit 28 , the second hydraulic delivery circuit 48 , and the delivery 64 of the electric actuator 52 from one another, where said delivery 64 supplies said first and second hydraulic supply circuits 16 , 36 .

[0044] Moreover, in back-up mode , the slide valve 108 puts into communication the first hydraulic delivery circuit 28 with the first hydraulic supply circuit 16 (which controls a first caliper mounted to the front wheel of the motorcycle , for example ) , and the second hydraulic delivery circuit 48 with the second hydraulic supply circuit 36 (which controls a second caliper mounted to the same front wheel of the motorcycle , for example ) , and where the slide valve 108 hydraulically separates the first and second hydraulic supply circuits 16 , 36 . By virtue of this hydraulic separation, the hydraulic circuits of the two manual controls for the rider are mutually independent , thus avoiding the action of one from biasing the characteristic of the other .

[0045] According to a possible embodiment ( figure 3 ) , the braking system 4 comprises a main hydraulic fluid tank 112 which supplies a first tank 100 of the first manually operated hydraulic device 20 and the second tank 104 of the second manually operated hydraulic device 40, where said main tank 112 is preloaded. Said first and second tanks 100,104 cannot be emptied because of the difference in the respective geodetic height. Preferably, said preload, e.g., obtained by means of a membrane biased by a spring 113, is such as not to generate a pressure which results in an actuation of the braking devices 12,32. Preferably, said valve means 68 comprise a slide valve 108 which selectively connects or disconnects the first and second hydraulic delivery circuits 28,48 to/from the first and second hydraulic supply circuits 16,36, respectively .

[0046] According to a possible embodiment (figure 4) , the braking system 4 comprises a first hydraulic braking simulator 92 connected to the first hydraulic delivery circuit 28 and a second hydraulic braking simulator 96 connected to the second hydraulic delivery circuit 48, each of said hydraulic braking simulators 92,96 being provided with a single hydraulic tank. Preferably, the valve means 68 comprise a slide valve 108 which selectively connects or disconnects the first and second hydraulic delivery circuits 28,48 to/from the first and second supply circuits 16,36, respectively. The free fluid bed is thus above everything else in the hydraulic circuit, whereby no preload is needed to avoid emptying across different tanks. Furthermore, in this configuration, non-return valves are also unnecessary since the tank is placed upstream of all pumps.

[0047] According to a possible embodiment (figure 5) , said slide valve 108 is divided into four two-way valves 116, preferably two normally closed (NC) valves and two normally open (NO) valves.

[0048] According to a possible embodiment (figure 6) , the system 4 comprises a single brake fluid tank 112 which supplies the first and second hydraulic delivery circuits 28,48, upstream of said valve means 68, said single tank 112 being preloaded under pressure (so as to ensure complete filling of the manual controls, whether a lever or a pedal, as a result of thermal expansion and pad wear, in both standard and back-up modes.

[0049] The absence of separate tanks provided on each manually operated hydraulic device 20,40 allows two functions. In back-up operation, it allows a pressure generation, e.g., by the pedal, and also pressurizes the manual lever control at rest, which would not be possible with a tank at ambient pressure. Moreover, the manually operated control, in particular the brake lever, is particularly aesthetically minimal, making the style of these components particularly innovative and unique. [0050] For example (figure 6) , the first and second hydraulic supply circuits 16,36 are fluidly connected to two braking devices 12,32 arranged at the front of the vehicle .

[0051] An embodiment (figure 7) is also possible, in which the first and second hydraulic supply circuits are coincident and fluidly connected to a single braking device arranged on the rear wheel of the motorcycle.

[0052] According to a further possible embodiment (figure 8) , said first and second manually operated hydraulic devices 20,40 are arranged in series with each other and with the first and second hydraulic supply circuits 16,36. Each manually operated hydraulic device 20,40 comprises a piston provided with a one-way lip seal (not shown) at the outlet of the device. It is thus possible to control a single caliper with both manually operated controls 24,44 according to a maximum logic.

[0053] For example, the braking system 4 comprises a brake fluid tank connected directly upstream of the electric actuator by means of a plurality of one-way valves 120 which allow the leakage of fluid with the system at atmospheric pressure while preventing the passage in the opposite direction during the actuations of the braking devices in both standard operation and back-up operation. [0054] According to a possible embodiment (figure 8) , said valve means 68 comprise two normally open hydraul ic valves 69 which fluidly connect both the manually operated hydraulic devices 20 , 40 and two normally closed hydraulic valves 70 to allow the passage of pressure between said manually operated hydraulic devices 20 , 40 and the hydraulic supply circuits 16 , 36 and prevent the absorption of volume by absorbers 92 , 96 connected to the manually operated hydraulic devices in back-up .

[0055] As can be appreciated from the description above , the present invention allows overcoming the drawbacks presented in the prior art .

[0056] In particular, the braking system of the present invention allows actuating the hydraulic back-up by means of both controls ( lever and brake pedal ) in case a failure of the E/E system (ECU, actuators , sensors , etc . ) or in case of lack of power supply ( disconnected battery) in combination with a partially fluid- free braking system actuation ( at least one caliper or fully electromechanical axle - DRY) .

[0057] Finally, the present invention allows providing braking systems being compatible with electric vehicles (blending with regenerative braking, residual torque reduction) .

[0058] In order to meet contingent , speci fic needs , those skilled in the art may make several changes and variations to the braking systems and motorcycles described above , all contained within the present invention as mechanical and/or functional equivalents .

[0059] The scope of protection of the invention is defined by the following claims .