Brake sense simulation device and method for actuating brake system

Abstract

In one aspect, the invention relates to a brake sensation simulator device (1) for a brake system (2), the brake sensation simulator device (1) being adapted to be connected to a brake pedal (3), where the brake sensation simulator device (1) comprises: a thrust piston (11); the thrust piston (11) is configured to be biased in a translational manner against the electromechanical counter device (5) in response to actuation of the brake pedal (3), and wherein the electromechanical counter device (5) is configured to counter translation of the thrust piston (11). In another aspect, the invention relates to a method of actuating a brake system.

Description

Technical Field

[0001] The present invention relates to a brake feel simulator device for a brake-by-wire ("BBW") type brake system of a vehicle having two or more wheels which can be actuated by a driver via a brake pedal or lever, and a brake system provided with such a brake feel simulator device. Background Art

[0002] In a BBW type braking system, there is a decouple between the force and displacement applied by the driver to the brake pedal or lever and the resulting braking force applied by the calipers to the wheels.

[0003] In a BBW braking system, the force and displacement applied by the driver to the brake pedal or lever is converted into an electrical signal which is processed by a control unit to control the actuation of the brake system calipers.

[0004] Therefore, it is known to equip a BBW braking system with a brake feel simulator device, referred to as a "simulator device", which is connected to a brake pedal or rod and is constructed to simulate the feel and stiffness of a brake pedal or rod of a conventional hydraulic braking system, and thereby simulate the "stiffness curve" of a brake pedal or rod of a conventional hydraulic braking system.

[0005] "Stiffness curve" refers to the relationship between the displacement of the brake pedal or lever along the stroke of the brake pedal or lever and the corresponding reaction force applied by the simulator device to the brake pedal or lever and therefore by the brake pedal or lever to the driver. Typically, the stiffness curve includes a first section with low stiffness, a second section with medium stiffness, and a third section with high stiffness. In addition, in general, for an "aggressive" or "sporty" driving style, a steeper "hard" stiffness curve is preferred, while for an "urban" or "eco" driving style, a less steep "soft" stiffness curve is preferred.

[0006] In the related art, the stiffness curve of the simulator device may be pre-designed based on the driver's needs so that the brake pedal or lever has the "hardness" required by the driver.

[0007] Known simulator devices comprise a plurality of elastic elements, typically helical springs, which are arranged in series or in parallel and are configured to apply a total reaction force, depending on the tensile or compressive stress of the elastic elements, which replicates the stiffness curve of a conventional hydraulic brake system.

[0008] However, known simulator devices do not allow the stiffness curve to be adjusted or adjusted, and therefore do not allow the "hardness" of the brake pedal or lever to be adjusted or adjusted without completely redesigning the simulator device. Therefore, known simulator devices cannot be customized and adjusted to the needs of different driving styles unless the simulator device is removed from the brake system and components of the simulator device are redesigned and replaced.

[0009] Furthermore, the stiffness curves achieved by known simulator devices are subject to instabilities and changes over time, primarily due to mechanical tolerances of various components within the simulator device and in particular due to tolerances of groups of springs and elastic elements arranged in series and in parallel within the simulator device.

[0010] Furthermore, known simulator devices do not return haptic signals and feedback to the driver, such as, for example, vibrations of the brake pedal of a conventional braking system that would be triggered when the ABS intervenes. Summary of the invention

[0011] An object of the present invention is to provide a brake feel simulator device and a brake system provided with such a simulator device so as to obviate at least some of the disadvantages of the related art.

[0012] It is a particular object of the present invention to provide a simulator device which is configured to allow adjustment and customization of the stiffness curve of the simulator device without requiring a complete redesign.

[0013] Another specific object of the invention is to provide a simulator device which is more stable, more efficient and less susceptible to the mechanical degradation typical of known simulator devices.

[0014] Another specific object of the present invention is to provide a simulator device configured to return tactile signals and feedback to the driver, such as vibration of the brake pedal of a conventional braking system triggered when ABS intervention.

[0015] These and other objects are achieved by a brake feel simulator device and a brake system provided with such a simulator device according to the independent claims.

[0016] The dependent claims relate to preferred and advantageous embodiments of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to better understand the present invention and appreciate its advantages, some non-limiting exemplary embodiments of the present invention will be described below with reference to the accompanying drawings, in which:

[0018] - Figure 1Schematically shows a brake system including a brake feeling simulator device according to the prior art;

[0019] - Figure 2 Schematically shows a braking system including a brake feeling simulator device according to an embodiment of the present invention;

[0020] - Figure 3 is a front perspective view of a brake feel simulator device according to an embodiment of the present invention;

[0021] - Figure 4 yes Figure 3 A rear perspective view of the brake feel simulator device shown in ;

[0022] - Figure 5 yes Figure 3 A side view of the brake feel simulator device shown in ;

[0023] - Figure 6 yes Figure 5 A longitudinal cross-sectional view of a brake feel simulator device;

[0024] - Figure 7 is a longitudinal sectional view of a brake feel simulator device according to an embodiment of the present invention;

[0025] - Figure 8 is an exploded perspective view of a brake feel simulator device according to an embodiment of the present invention;

[0026] - Fig. 9 yes Figure 8 Another exploded perspective view of the brake feel simulator device shown in ;

[0027] - Fig.10 is an exploded perspective view of a brake feel simulator device according to an embodiment of the present invention;

[0028] - Fig.11 yes Fig.10 Another exploded perspective view of the brake feel simulator device shown in ;

[0029] - Fig.12 is an exploded perspective view of a brake feel simulator device according to an embodiment of the present invention;

[0030] - Fig.13 yes Fig.12 Another exploded perspective view of the brake feel simulator device shown in ;

[0031] - Fig.14 Three different stiffness curves that can be achieved by the brake feel simulator device according to the invention are schematically shown. DETAILED DESCRIPTION

[0032] The present invention is suitable for being applied to a brake system of the brake-by-wire ("BBW") type for vehicles having two or more wheels, which brake system can be actuated by the driver by means of a brake pedal or lever. Therefore, in this specification, unless otherwise specified, the term "brake pedal" refers to both a brake pedal for a motor vehicle, etc., and a brake lever for a motorcycle, moped, etc.

[0033] Furthermore, a "hydraulic fluid" is a fluid adapted to be pressurized by a known pressurizing device when a brake pedal, or a brake feel simulator device, or a brake system is actuated.

[0034] Brake feeling simulator device 1

[0035] With reference to the drawings, a brake feel simulator device is generally indicated by reference numeral 1. The brake feel simulator device 1 is adapted to be used in a brake system 2.

[0036] The brake feel simulator device 1 is adapted to be fluidly connected to a brake pedal 3 .

[0037] Preferably, the brake feel simulator device 1 is adapted to be connected to the brake pedal 3 by means of a hydraulic fluid.

[0038] Thus, an actuation of the brake pedal 3 corresponds to a pressurization of the hydraulic fluid in the brake feel simulator device 1 , and to a subsequent actuation of the brake feel simulator device 1 .

[0039] The brake feel simulator device 1 includes a thrust piston 11 .

[0040] Furthermore, the brake feel simulator device 1 includes an electromechanical countermeasure device 5 .

[0041] The thrust piston 11 is configured to be biased in translation against the electromechanical countermeasure device 5 in response to an actuation of the brake pedal 3 .

[0042] Preferably, the thrust piston 11 is configured to be biased against the electromechanical countermeasure device 5 by a hydraulic fluid in response to actuation of the brake pedal 3 .

[0043] According to an aspect of the invention, the electromechanical counteracting means 5 are configured to counteract the translation of the thrust piston 11 .

[0044] Advantageously, the brake feel simulator device 1 so constructed allows the stiffness curve to be adjusted and customized without requiring a complete redesign.

[0045] In fact, with the help of the electromechanical antagonism device 5, the reaction force applied to the thrust piston 11 actuated in a translational manner by the brake pedal 3 can be changed and adjusted, and thus the reaction force released on the brake pedal 3 can be changed and adjusted, that is, the "hardness" of the stiffness curve of the brake feel simulator device 1 can be changed and adjusted.

[0046] A greater opposition of the electromechanical opposition device 5 to the translation of the thrust piston 11 corresponds to a greater resistance to the movement of the thrust piston 11 actuated by the brake pedal 3 and therefore to a greater reaction force opposing the actuation of the brake pedal 3 and a harder stiffness curve.

[0047] Conversely, less opposition to the translation of the thrust piston 11 by the electromechanical opposition device 5 corresponds to less resistance to the movement of the thrust piston 11 actuated by the brake pedal 3 and therefore to less reaction force resisting the actuation of the brake pedal 3 and a less stiff stiffness curve.

[0048] Another advantage is that the brake feel simulator 1 thus constructed is suitable for applying a reaction force to the brake pedal 3 that resists the actuation of the brake pedal 3 .

[0049] According to an embodiment, the electromechanical countermeasure device 5 comprises an electric motor 6 and a countermeasure mechanism 40 .

[0050] The counteracting mechanism 40 is configured to counteract the translation of the thrust piston 11 .

[0051] The electric motor 6 is configured to actuate the antagonism mechanism 40 so that the antagonism mechanism 40 opposes the translation of the thrust piston 11 .

[0052] According to an embodiment, the countermeasure mechanism 40 is an irreversible mechanism.

[0053] Advantageously, this configuration allows the countermeasure mechanism 40 to perform a retrograde movement without being actuated by the electric motor 6. Thus, without being actuated by the electric motor 6, the countermeasure mechanism 40 is configured to return to its rest position.

[0054] According to an embodiment, the counteracting mechanism 40 is positioned so as to be interposed between the thrust piston 11 and the electric motor 6 .

[0055] According to an embodiment, the counteracting mechanism 40 is a screw-nut type screw assembly 8 .

[0056] The screw-nut type screw assembly 8 faces the thrust piston 11 .

[0057] The screw-nut assembly 8 is coaxial with the actuation axis 13 .

[0058] The screw-nut type screw assembly 8 includes a screw 9 and a nut type screw 10 .

[0059] The screw 9 and the nut-screw 10 are connected to each other such that a relative translation of the nut-screw 10 relative to the screw 9 along the actuation axis 13 corresponds to a relative rotation of the screw 9 relative to the nut-screw 10 about the actuation axis 13 .

[0060] The electric motor 6 comprises a drive shaft 7 which extends along a motor axis 12 .

[0061] A screw-nut type screw assembly 8 is connected to the drive shaft 7 .

[0062] The electric motor 6 is configured to apply a mechanical torque to at least one of the screw 9 and the nut screw 10 .

[0063] Furthermore, the thrust piston 11 is configured to be biased against the screw-nut screw assembly 8 in response to actuation of the brake pedal 3 .

[0064] Thus, the thrust piston 11 translates at least one of the threaded rod 9 and the nut screw 10 along the actuation axis 13 .

[0065] Furthermore, the electric motor 6 is configured to oppose said translation of the thrust piston 11 and of at least one of the screw 9 and the nut screw 10 along the actuation axis 13 by applying a mechanical opposing torque to the screw-nut screw assembly 8 .

[0066] Advantageously, the brake feel simulator device 1 thus constructed allows modification of the stiffness curve according to which a reaction force is applied that resists the actuation of the brake pedal 3 .

[0067] In practice, the brake feel simulator device 1 applies reaction forces of different strengths to resist the actuation of the brake pedal 3 according to the strength of the mechanical antagonistic torque applied by the electric motor 6 to the screw-nut screw assembly 8 .

[0068] Specifically, the brake feel simulator device 1 thus constructed allows a "soft" stiffness curve to be achieved under conditions where the mechanical antagonistic torque applied by the electric motor 6 has a smaller amplitude. Under such conditions, since the antagonistic effect of the electric motor 6 opposing the translation of the thrust piston 11 is smaller, the actuation of the brake pedal 3 and thus the subsequent translation of the thrust piston 11 toward the electromechanical antagonistic device 5 are subject to less resistance from the brake feel simulator device 1.

[0069] On the contrary, the brake feel simulator device 1 thus constructed allows a "hard" stiffness curve to be achieved under conditions where the mechanical antagonistic torque applied by the electric motor 6 has a relatively large amplitude. Under such conditions, the actuation of the brake pedal 3 and therefore the subsequent translation of the thrust piston 11 toward the electromechanical antagonistic device 5 are subject to relatively large resistance by the brake feel simulator device 1, due to the relatively large antagonistic effect of the electric motor 6 opposing the translation of the thrust piston 11.

[0070] An additional advantage is that a brake feel simulator device 1 constructed in this manner allows modification of the stiffness curve according to which a reaction force is applied to resist actuation of the brake pedal 3, without the need to redesign or replace components of the simulator device, simply by modifying the strength of the mechanical counteracting torque applied by the electric motor 6.

[0071] An additional advantage is that the brake feel simulator device 1 constructed in this way has a simplified structure and is more stable, more efficient and less susceptible to mechanical degradation typical of known simulator devices.

[0072] Another advantage is that the brake feel simulator device 1 thus constructed allows providing a tactile signal and feedback to the driver, such as the vibration of the brake pedal of a conventional brake system triggered when the ABS intervenes. This is achieved through the action of the electric motor 6, which is configured to change the intensity of the mechanical antagonistic torque applied to the screw-nut screw assembly 8 and then transmitted to the brake pedal 3 to obtain the desired tactile signal or vibration.

[0073] According to an embodiment, the electromechanical countermeasure device 5 comprises a housing 16 extending along the actuation axis 13 .

[0074] The receiving portion 16 defines an receiving compartment 17 within the receiving portion 16 .

[0075] The screw-nut type screw assembly 8 is accommodated inside the accommodation compartment 17 .

[0076] Preferably, the housing 16 is substantially cylindrical in shape and is coaxial with the actuation axis 13 .

[0077] According to an embodiment, the screw 9 of the screw-nut type screw assembly 8 is connected to the drive shaft 7 of the electric motor 6 .

[0078] Therefore, the screw 9 is configured to receive mechanical torque from the electric motor 6 .

[0079] The nut-type screw 10 of the lead screw-nut-type screw assembly 8 is configured to translate along an actuation axis 13 relative to the lead screw 9 and the electric motor 6 .

[0080] Furthermore, the nut screw 10 is configured to translate relative to the receiving portion 16 but not to rotate.

[0081] The thrust piston 11 is configured to be biased against the nut screw 10 in response to actuation of the brake pedal 3 , preferably, the thrust piston 11 is configured to be biased against the nut screw 10 by a hydraulic fluid in response to actuation of the brake pedal 3 .

[0082] The thrust piston 11 thus translates the nut-screw 10 along the actuation axis 13 .

[0083] According to this embodiment, the electric motor 6 is configured to oppose the translation of the nut-screw 10 along the actuation axis 13 by applying a mechanical opposing torque to the screw 9 .

[0084] Specifically, the mechanical antagonistic torque applied by the electric motor 6 to the screw 9 biases the screw 9 in a rotational direction opposite to the direction in which the screw 9 rotates when the nut screw 10 is translated under the biasing action of the thrust piston 11. Therefore, the mechanical antagonistic torque opposes the rotation of the screw 9 caused by the translation of the nut screw 10 under the biasing action of the thrust piston 11.

[0085] Advantageously, the mechanical counteracting torque of the electric motor 6, which opposes the translation of the nut screw 10, achieved by the screw 9, modifies the magnitude of the total reaction force applied by the brake feel simulator device 1 to the brake pedal 3. In particular, adjustment of the intensity of the mechanical counteracting torque applied by the electric motor 6 results in adjustment of the stiffness curve of the brake feel simulator device 1 and thus in adjustment of the reaction force returned to the driver actuating the brake pedal 3.

[0086] According to an embodiment, the screw-nut assembly 8 and the electric motor 6 are positioned such that the actuation axis 13 coincides with the motor axis 12 .

[0087] According to an embodiment, the electric motor 6 is positioned opposite the thrust piston 11 with respect to the screw-nut screw assembly 8 .

[0088] Advantageously, this configuration ensures the integrity and structural strength of the electromechanical countermeasure device 5 .

[0089] According to an embodiment, the nut screw 10 is positioned opposite the electric motor 6 with respect to the threaded rod 9 .

[0090] According to this embodiment, the thrust piston 11 is configured to translate the nut screw 10 in the direction of the electric motor 6 .

[0091] Advantageously, such a configuration reduces the overall stresses to which the electromechanical countermeasure device 5 is subjected during operation of the electromechanical countermeasure device 5 .

[0092] According to an embodiment of the invention, the electromechanical countermeasure device 5 comprises a transmission device 14 .

[0093] The transmission device 14 is arranged between the electric motor 6 and the screw-nut type screw assembly 8 .

[0094] Preferably, the transmission 14 is a reversible transmission, for example, the transmission 14 is a planetary transmission, a harmonic or cycloid reduction gear, or a cascade gear distribution.

[0095] According to an embodiment, the electromechanical countermeasure device 5 comprises a support 15 arranged between the electric motor 6 and the screw-nut assembly 8 .

[0096] Preferably, the bearing 15 is a thrust type bearing. Preferably, the bearing 15 is a ball type bearing or a roller type bearing.

[0097] According to an embodiment, the nut-type screw 10 is translatable between a stroke start position 24 located at the thrust piston 11 and a stroke stop position 25 opposite the thrust piston 11 with respect to the nut-type screw 10 .

[0098] According to an embodiment, the electromechanical countermeasure device 5 comprises a first elastic element 23 .

[0099] The first elastic element 23 is configured to bias the nut-type screw 10 toward a stroke start position.

[0100] Therefore, during operation of the brake feel simulator device 1, the nut screw 10 is translated by the thrust piston 11 from the stroke start position 24 to the stroke end position 25. This movement of the nut screw 10 is opposed by the mechanical opposing torque of the electric motor 6 and the elastic force applied by the first elastic element 23. When the actuation of the brake feel simulator device 1 is interrupted, the first elastic element 23 biases the nut screw 10 back to the stroke start position 24.

[0101] Furthermore, the first elastic element 23 is configured to bias the electromechanical antagonism device 5 towards a rest position of the electromechanical antagonism device 5. The rest position refers to the position of the electromechanical antagonism device 5 when the electromechanical antagonism device 5 is not biased by the hydraulic fluid, i.e. the position of the electromechanical antagonism device 5 when the electromechanical antagonism device 5 is not actuated in response to an actuation of the brake pedal 3.

[0102] Advantageously, the return of the nut-type screw 10 to the stroke start position 24 is facilitated by the transmission device 14 of the reversible type.

[0103] According to an embodiment, the first elastic element 23 is a helical compression spring.

[0104] According to a preferred embodiment, the helical compression spring 23 is positioned coaxially with the screw 9 of the screw-nut type screw assembly 8 .

[0105] Advantageously, this positioning reduces the overall dimensions of the electromechanical countermeasure device 5 .

[0106] According to an embodiment, the electromechanical countermeasure device 5 comprises a second backing body 19 .

[0107] The backing body 19 is fixed inside the accommodation compartment 17 in such a manner as to be disposed opposite to the thrust piston 11 with respect to the nut screw 10 .

[0108] According to an embodiment, the backing body 19 is formed with a travel stop wall 26 facing the nut-type screw 10 .

[0109] The travel stop wall 26 defines a travel stop position 25 of the nut-type screw 10 .

[0110] Specifically, the travel stop wall 26 is positioned so that the nut-type screw 10 translated by the thrust piston 11 abuts against the travel stop wall 25 of the nut-type screw 10 .

[0111] Advantageously, by means of the backing body 19 , the travel stop for actuating the electromechanical antagonism device 5 and therefore for the brake feel simulator device 1 and the brake pedal 3 can be adjusted.

[0112] According to an embodiment, the backing body 19 is hollow in a direction parallel to the actuation axis 13 .

[0113] According to this embodiment, the screw 9 of the screw-nut screw assembly 8 at least partially passes through the backing body 19 along the actuation axis 13 .

[0114] According to an embodiment, the backing body 19 comprises a peripheral wall 20 extending along the actuation axis 13 , preferably the peripheral wall 20 is coaxial with the actuation axis 13 .

[0115] Furthermore, the backing body 19 comprises a backing wall 21 which is transverse to the actuation axis 13 .

[0116] The backing wall 21 extends from the peripheral wall 20 in a radial direction towards the actuation axis 13 .

[0117] According to an embodiment, the backing wall 21 defines a through hole 22 coaxial with the actuation axis 13 .

[0118] The screw 9 of the screw-nut type screw assembly 8 extends through the through hole 22 of the backing wall 21 .

[0119] The backing wall 21 forms a first backing surface 27 facing the nut-screw 10 and an opposite second backing surface 28 facing the electric motor 6 .

[0120] According to an embodiment, a first end of the first elastic element 23 is positioned against the nut-screw 10 and an opposite second end of the first elastic element 23 is positioned against the first backing surface 27 of the backing body 19 .

[0121] According to an embodiment, the transmission 14 or the support 15 is positioned against the second backing surface 28 .

[0122] According to a preferred embodiment, the support 15 is positioned against the second backing surface 28 and the transmission 14 is positioned against the support 15 .

[0123] According to this embodiment, the support 15 and the transmission 14 are at least partially housed inside the backing housing 19 , preferably, the support 15 and the transmission 14 are completely housed inside the backing housing 19 .

[0124] Advantageously, this configuration reduces the overall dimensions of the electromechanical countermeasure device 5 .

[0125] According to an embodiment, the electromechanical countermeasure device 5 comprises a second elastic element 29 .

[0126] The second elastic element 29 is disposed between the screw-nut type screw assembly 8 and the thrust piston 11 .

[0127] The second elastic element 29 is configured to bias the screw-nut type screw assembly 8 away from the thrust piston 11 .

[0128] According to an embodiment, the second elastic element 29 is disposed between the nut screw 10 and the thrust piston 11 , and the second elastic element 29 is configured to bias the nut screw 10 away from the thrust piston 11 .

[0129] Advantageously, the second elastic element 29 prevents the thrust piston 11 biased by the hydraulic fluid from suddenly hitting the nut screw 10, thereby risking damage to the component. Instead, the second elastic element 29 is configured to adjust the movement, proximity and relative contact between the thrust piston 11 and the nut screw 10.

[0130] According to an embodiment, the second elastic element 29 is a helical compression spring.

[0131] According to an embodiment, the thrust device 11 is formed with a blind piston cavity. The blind piston cavity is open in the direction of the nut screw 10 .

[0132] According to an embodiment, the second elastic element 29 is at least partially housed inside the blind piston cavity.

[0133] Advantageously, this configuration reduces the overall dimensions of the electromechanical countermeasure device 5 .

[0134] According to an embodiment, a first end of the second elastic element 29 is positioned against the thrust piston 11 inside the blind piston cavity, while an opposite second end of the second elastic element 29 is positioned against the nut-type screw 10 .

[0135] According to an embodiment, the thrust piston 11 comprises an offset wall 30 substantially transverse to the actuation axis 13 .

[0136] Furthermore, the thrust piston 11 comprises a thrust wall 31 which extends in a direction parallel to the actuation axis 13 and transversely to the thrust wall 31 .

[0137] The thrust piston 11 is configured to receive a hydraulic fluid bias on the biasing wall 30 , and the hydraulic fluid bias is suitable for moving the thrust piston 11 toward the screw-nut screw assembly 8 in a translational manner. Preferably, the hydraulic fluid biasing action is suitable for moving the thrust piston 11 toward the nut screw 10 in a translational manner.

[0138] The offset wall 30 faces the delivery duct 32 .

[0139] The delivery conduit 32 is configured to fluidly connect the brake feel simulator device 1 to the brake pedal 3 through a hydraulic fluid.

[0140] Specifically, the delivery pipe 32 is configured to: when the brake feel simulator device 1 is activated and the brake pedal 3 is activated, the delivery pipe 32 delivers the hydraulic fluid to the brake feel simulator device 1; and, when the brake feel simulator device 1 is deactivated and the brake pedal 3 is released, the delivery pipe 32 discharges the hydraulic fluid from the brake feel simulator device 1.

[0141] Preferably, the delivery conduit 32 is at least partially defined by the receiving portion 16 .

[0142] The thrust wall 31 faces the screw-nut type screw assembly 8 and is configured to abut against the screw-nut type screw assembly 8 when the brake feel simulator device 1 is actuated. Preferably, the thrust wall 31 is configured to abut against the nut type screw 10 when the brake feel simulator device 1 is actuated.

[0143] According to an embodiment, the electric motor 6 is positioned against the housing 16 in a manner opposite to the thrust piston 11 and the delivery duct 32 .

[0144] Advantageously, this configuration reduces the overall stress acting on the brake feel simulator device 1 .

[0145] Braking system 2

[0146] According to another aspect of the present invention, a brake system 2 comprises a brake feel simulator device 1 as described above.

[0147] Furthermore, the brake system 2 includes a brake pedal 3 operatively connected to the brake feel simulator device 1 .

[0148] Advantageously, the brake system 2 constructed in this way allows a reaction force against actuation of the brake pedal to be achieved on the brake pedal 3 following a stiffness curve by means of the brake feel simulator device 1. Furthermore, this stiffness curve can be modified and adjusted by means of the brake feel simulator device 1.

[0149] According to a possible embodiment, the brake system 2 comprises an absorber 4 configured to apply to the brake pedal 3 a reaction force opposing an actuation of the brake pedal 3 .

[0150] In particular, the absorber 4 is configured to apply a reaction force to the brake pedal 3 that resists the actuation of the brake pedal 3 according to a stiffness curve, i.e., according to a defined relationship between the displacement of the brake pedal 3 along the stroke of the brake pedal 3 and the corresponding reaction force applied by the absorber 4.

[0151] According to the embodiment, the brake feel simulator device 1 is fluidly connected to the absorber 4 .

[0152] In particular, the electromechanical countermeasure device 5 is fluidically connected to the absorber 4 .

[0153] The absorber 4 and the electromechanical antagonism device 5 are fluidically connected by a hydraulic fluid.

[0154] The absorber 4 and the brake feel simulator device 1 are operable by means of a hydraulic fluid in response to actuation of the brake pedal 3 .

[0155] The absorber 4 is of a known type, i.e. an absorber comprising a plurality of elastic elements, typically helical springs, which are arranged in series or in parallel and are configured to apply a total reaction force replicating the stiffness curve of a conventional hydraulic brake system, depending on the tensile or compressive stress of the elastic elements.

[0156] Advantageously, the brake system 2 thus constructed allows a reaction force on the brake pedal 3 to be achieved that resists actuation of the brake pedal following a stiffness curve by means of the combined action of the absorber 4 and the brake feel simulator device 1. In addition, this stiffness curve can be modified and adjusted by the brake feel simulator device 1.

[0157] The stiffness curve achieved only by the absorber 4 is predefined. This stiffness curve is variable and can be modified by an electromechanical antagonism device 5 fluidically connected to the absorber 4 by means of a hydraulic fluid.

[0158] Advantageously, a brake system 2 constructed in this way in which the brake feel simulator device 1 is connected to the absorber 4 allows modification and adjustment of a predefined stiffness curve that can be achieved by the absorber 4 on the brake pedal 3, and thus allows a brake system 2 to be obtained whose stiffness curve is modifiable and adjustable.

[0159] According to this embodiment, if the mechanical antagonistic torque applied by the electric motor 6 is substantially zero, the reaction force applied to the brake pedal 3 roughly follows the stiffness curve of the absorber 4 itself, and the effect of the electromechanical antagonism device 5 on the absorber 4 is only due to the inertia of the electric motor 6 connected to the antagonism mechanism 40.

[0160] According to the embodiment, the delivery conduit 32 of the brake feel simulator device 1 is configured to fluidly connect the brake feel simulator device 1 to the absorber 4 by means of a hydraulic fluid.

[0161] According to an embodiment, the brake system 2 comprises an electronic processing unit 18 which is electrically connected to the electric motor 6 of the brake feel simulator device 1 .

[0162] Furthermore, the brake system 2 comprises at least one sensor which is configured to detect an actuation and / or a movement of the brake pedal 3 .

[0163] The electronic processing unit 18 is configured to actuate the electric motor 6 of the electromechanical countermeasure device 5 only when an actuation and / or a movement of the brake pedal 3 is detected by the at least one sensor.

[0164] Advantageously, this configuration allows energy saving and low stress of the brake feel simulator device 1 to be achieved.

[0165] According to an alternative embodiment, the electronic processing unit 18 is configured to actuate the electric motor 6 of the electromechanical countermeasure device 5 to continuously bias the nut screw 10 of the screw-nut screw assembly 8 toward the starting position 24 of the stroke of the nut screw 10, regardless of the actuation of the brake pedal 3.

[0166] Advantageously, such a configuration allows even faster response times to be obtained by the brake feel simulator device 1 , since even the slightest response delay of the brake feel simulator device 1 due to the transmission of the activation command from the electronic processing unit 18 to the electric motor 6 is eliminated.

[0167] According to an embodiment, the electronic processing unit 18 is configured to command the brake feel simulator device 1 to implement a stiffness curve selectable from a plurality of stiffness curves.

[0168] According to this embodiment, each selectable stiffness curve corresponds to a given value of mechanical antagonistic torque that can be applied by the electric motor 6 to the spindle-nut screw assembly 8 .

[0169] Alternatively, each selectable stiffness curve corresponds to a given tendency of the mechanical antagonistic torque that can be applied by the electric motor 6 to the screw-nut-screw assembly 8 , the given tendency varying as a function of the movement of the brake pedal 3 and / or the translation of the nut-screw 10 .

[0170] Advantageously, this tendency of the mechanical resisting torque that can be applied by the electric motor 6 to the screw-nut screw assembly 8 and that varies according to the movement of the brake pedal 3 and / or the translation of the nut screw 10 can be customized based on the needs of a specific driver so that a customized stiffness curve can be obtained for the specific driver.

[0171] According to an embodiment, the brake system 2 is configured to obtain at least two different stiffness curves, preferably, the brake system 2 is configured to obtain at least three different stiffness curves.

[0172] The stiffness curve differs due to the difference in the steepness of the stiffness curve, and therefore, the stiffness curve differs due to the difference in the hardness that can be perceived by the driver operating the brake pedal 3 .

[0173] For example, the driver can select from three different stiffness curves, eg, called “Sport”, “Drive” and “City”, depending on the corresponding stiffness.

[0174] According to an embodiment, the brake system 2 comprises a selection device connected to the electronic processing unit 18 .

[0175] The selection device is configured to allow the driver to select a stiffness curve from a plurality of predetermined stiffness curves of the brake feel simulator device 1 .

[0176] According to an embodiment, the brake system 2 comprises a master cylinder 33 connected to the brake pedal 3 .

[0177] The master cylinder 33 includes a floating member 34 which is arranged to be moved by the driver's mechanical action on the brake pedal 3. The floating member 34 has a function of pressurizing the hydraulic fluid.

[0178] Furthermore, hydraulic fluid is contained in a reservoir 35 which is fluidly connected to the master cylinder 33 .

[0179] The master cylinder 33 is fluidically connected to the absorber 4 by means of a first hydraulic conduit 36 ​​containing hydraulic fluid.

[0180] According to an embodiment, the first on-off valve 37 is arranged along the first hydraulic conduit 36. The on-off valve 37 can be opened and closed; in the open configuration, the on-off valve 37 allows fluid connection between the master cylinder 33 and the absorber 4; in the closed configuration, the on-off valve 37 disconnects the absorber 4 from the master cylinder 33.

[0181] According to an embodiment, the braking system 2 also comprises a second hydraulic duct 38 operatively connected to at least one braking device associated with a wheel of the vehicle.

[0182] The second hydraulic conduit 38 is connected to the first hydraulic conduit 36 ​​via a second on-off valve 39 .

[0183] Similarly, the second on-off valve 39 can be opened and closed; in the open configuration, the second on-off valve 39 allows fluid connection between the master cylinder 33 and the brake device, so that the driver can directly operate the brake device in a conventional hydraulic actuation manner by acting on the brake pedal 3. In the closed configuration, the second on-off valve 39 prevents direct hydraulic connection between the master cylinder 33 and the brake device. Therefore, in the event of a malfunction of the electric actuation device or a power failure, the second hydraulic conduit serves as a backup.

[0184] Actuation method

[0185] According to another aspect of the present invention, a method for actuating the braking system 2 as described above comprises the following steps:

[0186] - selecting a stiffness curve by means of a selection device from a plurality of predefined stiffness curves achievable by the brake feel simulator device 1 ;

[0187] - detecting the actuation of the brake pedal 3 by means of at least one sensor;

[0188] -When the actuation of the brake pedal 3 is detected, the electric motor 6 of the brake feel simulator device 1 is actuated with the aid of the electronic processing unit 18, so that the electric motor 6 applies a mechanical counteracting torque to the screw-nut screw assembly 8; preferably, when the actuation of the brake pedal 3 is detected, the electric motor 6 of the brake feel simulator device 1 is actuated with the aid of the electronic processing unit 18, so that the electric motor 6 applies a mechanical counteracting torque to the screw-nut screw assembly 8 to resist the translation of the nut screw 10.

[0189] Preferably, the method comprises the following items after the above steps:

[0190] - detection of the interruption of the actuation of the brake pedal 3 by means of at least one sensor;

[0191] When an interruption of the actuation of the brake pedal 3 is detected, the electric motor 6 of the brake feel simulator device 1 is deactivated by means of the electronic processing unit 18 .

[0192] According to an alternative embodiment, the method for actuating the braking system 2 as described above comprises the following steps:

[0193] - selecting a stiffness curve from a plurality of predefined stiffness curves of the brake feel simulator device 1 by means of a selection device;

[0194] - The electric motor 6 of the brake feel simulator device 1 is actuated with the aid of the electronic processing unit 18, so that the electric motor 6 applies a mechanical antagonistic torque to the screw-nut screw assembly 8, regardless of the actuation of the brake pedal 3; preferably, the electric motor 6 of the brake feel simulator device 1 is actuated with the aid of the electronic processing unit 18, so that the electric motor 6 applies a mechanical antagonistic torque to the screw-nut screw assembly 8 to resist the translation of the nut screw 10, regardless of the actuation of the brake pedal 3.

[0195] It will be apparent that those skilled in the art will be able to make changes or modifications to the present invention without departing from the scope of the appended claims.

[0196] Reference numerals list

[0197] 1. Brake feel simulator device

[0198] 2. Braking system

[0199] 3. Brake pedal

[0200] 4. Absorber

[0201] 5. Electromechanical countermeasures

[0202] 6. Electric Motor

[0203] 7. Drive shaft

[0204] 8. Screw-nut type screw assembly

[0205] 9. Screw

[0206] 10. Nut

[0207] 11. Thrust piston

[0208] 12. Motor axis

[0209] 13. Actuation axis

[0210] 14. Transmission

[0211] 15. Support

[0212] 16. Accommodation

[0213] 17. Storage compartment

[0214] 18. Electronic processing unit

[0215] 19. Backing body

[0216] 20. Peripheral wall

[0217] 21. Backing wall

[0218] 22. Through hole

[0219] 23. First elastic element

[0220] 24. Stroke start position

[0221] 25. Travel stop position

[0222] 26. Travel stop wall

[0223] 27. First backing surface

[0224] 28. Second backing surface

[0225] 29. Second elastic element

[0226] 30. Offset wall

[0227] 31. Thrust wall

[0228] 32. Transportation pipeline

[0229] 33. Master cylinder

[0230] 34. Floating parts

[0231] 35. Storage

[0232] 36. First hydraulic conduit

[0233] 37. First on-off valve

[0234] 38. Second hydraulic conduit

[0235] 39. Second on-off valve

[0236] 40. Adversity institutions.

Claims

1. A brake feeling simulator device (1) for a brake system (2), the brake feeling simulator device (1) being adapted to be connected to a brake pedal (3), in, The brake feeling simulator device (1) comprises: - thrust piston (11); - electromechanical countermeasure device (5), wherein the thrust piston (11) is configured to be biased in translation against the electromechanical countermeasure device (5) in response to actuation of the brake pedal (3), And wherein the electromechanical counteracting device (5) is configured to counteract the translation of the thrust piston (11).

2. The brake feeling simulator device (1) according to claim 1, wherein: The electromechanical countermeasure device (5) comprises an electric motor (6) and a countermeasure mechanism (40), wherein the countermeasure mechanism (40) is configured to counteract the translation of the thrust piston (11), wherein the electric motor (6) is configured to actuate the countermeasure mechanism (40) so that the countermeasure mechanism (40) counteracts the translation of the thrust piston (11), And wherein the countermeasure mechanism (40) is a reversible mechanism.

3. The brake feeling simulator device (1) according to claim 1 or 2, wherein: The electromechanical countermeasure device (5) comprises an electric motor (6) and a countermeasure mechanism (40), wherein the countermeasure mechanism (40) is configured to counteract the translation of the thrust piston (11), wherein the electric motor (6) is configured to actuate the countermeasure mechanism (40) so that the countermeasure mechanism (40) counteracts the translation of the thrust piston (11), The counteracting mechanism (40) is a screw-nut type screw assembly (8) coaxial with the actuating axis (13), The screw-nut screw assembly (8) comprises a screw (9) and a nut screw (10), wherein the screw (9) and the nut screw (10) are connected to each other so that a relative translation of the nut screw (10) relative to the screw (9) along the actuation axis (13) corresponds to a relative rotation of the screw (9) relative to the nut screw (10) around the actuation axis (13), The electric motor (6) comprises a drive shaft (7) extending along a motor axis (12). wherein the screw-nut screw assembly (8) is connected to the drive shaft (7), and the electric motor (6) is configured to apply a mechanical torque to at least the screw (9) or the nut screw (10), wherein the thrust piston (11) is configured to be biased against the screw-nut screw assembly (8) in response to actuation of the brake pedal (3) so as to cause at least the screw (9) or the nut screw (10) to translate along the actuation axis (13), and wherein the electric motor (6) is configured to resist the translation of the thrust piston (11) and resist the translation of at least the screw (9) or the nut screw (10) along the actuation axis (13) by applying a mechanical resisting torque to the screw-nut screw assembly (8).

4. The brake feeling simulator device (1) according to claim 3, wherein: The electromechanical countermeasure device (5) comprises a housing portion (16) extending along the actuation axis (13), wherein, within the accommodating portion (16), the accommodating portion (16) defines an accommodating compartment (17), and wherein the screw-nut type screw assembly (8) is accommodated in the accommodating compartment (17), wherein the screw (9) of the screw-nut screw assembly (8) is connected to the drive shaft (7) of the electric motor (6) such that the screw (9) is configured to receive mechanical torque from the electric motor (6), The nut screw (10) of the screw-nut screw assembly (8) is configured to translate relative to the screw (9) and the electric motor (6) along the actuation axis (13), but not to rotate relative to the receiving portion (16). wherein the thrust piston (11) is configured to be biased against the nut screw (10) in response to actuation of the brake pedal (3) so that: the thrust piston (11) causes the nut screw (10) to translate along the actuation axis (13), And wherein the electric motor (6) is configured to resist the translation of the nut screw (10) along the actuation axis (13) by applying a mechanical resistive torque to the screw (9).

5. The brake feeling simulator device (1) according to claim 3 or 4, wherein: The screw-nut assembly (8) and the electric motor (6) are positioned so that the actuation axis (13) coincides with the motor axis (12), and / or wherein the electric motor (6) is positioned opposite to the thrust piston (11) with respect to the screw-nut screw assembly (8), And / or wherein the nut screw (10) is positioned opposite to the electric motor (6) relative to the screw rod (9), and the thrust piston (11) is configured to translate the nut screw (10) in the direction of the electric motor (6).

6. The brake feeling simulator device (1) according to claim 3, wherein: The electromechanical countermeasure device (5) comprises a transmission device (14), wherein the transmission device (14) is arranged between the electric motor (6) and the screw-nut screw assembly (8), and the transmission device (14) is a reversible transmission device, And optionally, the transmission device (14) is a planetary transmission device, or a harmonic or cycloid reducer, or a cascade gear distribution element, And / or wherein the electromechanical countermeasure device (5) comprises a support member (15), wherein the support member (15) is arranged between the electric motor (6) and the screw-nut screw assembly (8), and optionally, the support member (15) is a ball thrust type support member or a roller thrust type support member.

7. The brake feeling simulator device (1) according to claim 4, wherein: The nut screw (10) is capable of translationally moving between a stroke starting position (24) located at the thrust piston (11) and a stroke stopping position (25) opposite to the thrust piston (11) relative to the nut screw (10). The electromechanical countermeasure device (5) comprises a first elastic element (23), wherein the first elastic element (23) is configured to bias the nut screw (10) toward the stroke starting position. And optionally, the first elastic element (23) is a helical compression spring, and optionally, the helical compression spring is arranged coaxially with the screw (9) of the screw-nut screw assembly (8).

8. The brake feeling simulator device (1) according to claim 4, wherein: The electromechanical countermeasure device (5) comprises a backing body (19) which is fixed inside the accommodation compartment (17) in a manner opposite to the thrust piston (11) with respect to the nut screw (10). The backing body (19) is formed with a travel stop wall (26) facing the nut-type screw (10), and the travel stop wall (26) defines a travel stop position (25) of the nut-type screw (10). and / or wherein the backing body (19) is hollow in a direction parallel to the actuation axis (13), and the screw (9) of the screw-nut screw assembly (8) at least partially passes through the backing body (19) along the actuation axis (13), and / or wherein the backing body (19) comprises a peripheral wall (20) extending along the actuation axis (13), and a backing wall (21) transverse to the actuation axis (13), wherein the backing wall (21) extends from the peripheral wall (20) in a radial direction toward the actuation axis (13), and the backing wall (21) defines a through hole (22) coaxial with the actuation axis (13), wherein the screw (9) of the screw-nut screw assembly (8) extends through the through hole (22) of the backing wall (21), and optionally, the backing wall (21) is formed with a first backing surface (27) facing the nut screw (10) and an opposite second backing wall (28) facing the electric motor (6), wherein a first end of the first elastic element (23) is positioned against the nut screw (10), and an opposite second end of the first elastic element (23) is positioned against the first backing wall (27) of the backing body (19), And optionally, a support (15) is positioned against said second backing surface (28), and a transmission (14) is arranged against said support (15).

9. The brake feeling simulator device (1) according to claim 3, wherein: The electromechanical countermeasure device (5) comprises a second elastic element (29), wherein the second elastic element (29) is arranged between the screw-nut screw assembly (8) and the thrust piston (11). wherein the second elastic element (29) is configured to bias the screw-nut screw assembly (8) away from the thrust piston (11), And optionally, the second elastic element (29) is arranged between the nut screw (10) and the thrust piston (11), and the second elastic element (29) is configured to bias the nut screw (10) away from the thrust piston (11), and the second elastic element (29) is a helical compression spring.

10. The brake feeling simulator device (1) according to claim 9, wherein: The thrust piston (11) is formed with a blind piston cavity, and the blind piston cavity is open in the direction of the nut screw (10), and wherein the second elastic element (29) is at least partially accommodated inside the blind piston cavity, And optionally, a first end of the second elastic element (29) is positioned to abut against the thrust piston (11) inside the blind piston cavity, while an opposite second end of the second elastic element (29) is positioned to abut against the nut screw (10).

11. The brake feeling simulator device (1) according to claim 3, wherein: The thrust piston (11) comprises an offset wall (30) and a thrust wall (31), wherein the offset wall (30) is substantially transverse to the actuation axis (13), and the thrust wall (31) extends in a direction parallel to the actuation axis (13) and transverse to the thrust wall (31). The thrust piston (11) is configured to receive a hydraulic fluid stress on the offset wall (30), wherein the hydraulic fluid stress is suitable for causing the thrust piston (11) to move in a translational manner toward the screw-nut screw assembly (8), preferably, the hydraulic fluid stress is suitable for causing the thrust piston (11) to move in a translational manner toward the nut screw (10), wherein the offset wall (30) faces a delivery conduit (32), and the delivery conduit (32) is configured to fluidically connect the brake feel simulator device (1) to a brake pedal (3) by means of a hydraulic fluid, And wherein the thrust wall (31) faces the screw-nut type screw assembly (8), and the thrust wall (31) is configured to abut against the screw-nut type screw assembly (8) when the brake feeling simulator device (1) is actuated, preferably, the thrust wall (31) is configured to abut against the nut type screw (10) when the brake feeling simulator device (1) is actuated.

12. A braking system (2), comprising a brake feel simulator device (1) according to any one of the preceding claims, and comprising a brake pedal (3) operatively connected to the brake feel simulator device (1).

13. The braking system (2) according to claim 12, further comprising an absorber (4), the absorber (4) being configured to apply a reaction force to the brake pedal (3) that opposes the actuation of the brake pedal (3), and wherein, The absorber (4) is fluidly connected to the brake feel simulator device (1), and / or the absorber (4) is fluidly connected to the electromechanical countermeasure device (5) of the brake feel simulator device (1) by means of hydraulic fluid.

14. A braking system (2) according to claim 12 or 13, wherein the braking system (2) comprises an electronic processing unit (18), the electronic processing unit (18) being electrically connected to the electric motor (6) of the brake feeling simulator device (1), and the braking system (2) comprises at least one sensor, wherein the at least one sensor is configured to detect an actuation and / or movement of the brake pedal (3), in, The electronic processing unit (18) is configured to actuate the electric motor (6) of the electromechanical countermeasure device (5) only when an actuation and / or movement of the brake pedal (3) is detected by at least one sensor, Or wherein the electronic processing unit (18) is configured to actuate the electric motor (6) of the electromechanical countermeasure device (5) to continuously bias the nut screw (10) of the screw-nut screw assembly (8) toward a stroke starting position (24) of the nut screw (10), regardless of the actuation of the brake pedal (3).

15. The brake system (2) according to claim 14, wherein: The electronic processing unit (18) is configured to control the brake feel simulator device (1) to achieve a stiffness curve that can be selected from a plurality of stiffness curves, wherein each selectable stiffness curve corresponds to a given value of mechanical resistance torque that can be applied by the electric motor (6) to the screw-nut screw assembly (8), Alternatively, each selectable stiffness curve corresponds to a given tendency of a mechanical antagonistic torque that can be applied by the electric motor (6) to the screw-nut screw assembly (8), the given tendency varying according to the movement of the brake pedal (3) and / or the translation of the nut screw (10).

16. A method for actuating a brake system (2) according to claims 14 and 15, said method comprising the following steps: - using a selection device to select a stiffness curve from a plurality of predefined stiffness curves achievable by the brake feel simulator device (1); - detecting the actuation of the brake pedal (3) by means of at least one sensor; - When the actuation of the brake pedal (3) is detected, the electric motor (6) of the brake feeling simulator device (1) is actuated with the aid of an electronic processing unit (18) so that the electric motor (6) applies a mechanical counteracting torque to the screw-nut screw assembly (8); preferably, when the actuation of the brake pedal (3) is detected, the electric motor (6) of the brake feeling simulator device (1) is actuated with the aid of an electronic processing unit (18) so that the electric motor (6) applies a mechanical counteracting torque to the screw-nut screw assembly (8) that counteracts the translation of the nut screw (10); and optionally: - detecting the interruption of the actuation of the brake pedal (3) by means of at least one sensor; - when an interruption of the actuation of the brake pedal (3) is detected, the electric motor (6) of the brake feel simulator device (1) is deactivated by means of an electronic processing unit (18).

17. An actuation method of a brake system (2) according to claims 14 and 15, comprising the following steps: - selecting a stiffness curve from a plurality of predefined stiffness curves of the brake feel simulator device (1) using a selection device; - The electric motor (6) of the brake feeling simulator device (1) is actuated with the aid of an electronic processing unit (18) so that the electric motor (6) applies a mechanical counteracting torque to the screw-nut type screw assembly (8), regardless of the actuation of the brake pedal (3); preferably, the electric motor (6) of the brake feeling simulator device (1) is actuated with the aid of an electronic processing unit (18) so that the electric motor (6) applies a mechanical counteracting torque to the screw-nut type screw assembly (8) which is opposite to the translation of the nut type screw (10), regardless of the actuation of the brake pedal (3).

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